Violación del Principio de Equivalencia en Teorías con Dilatón de Cuerdas

NASA Astrophysics Data System (ADS)

Landau, S. J.; Sisterna, P. D.; Vucetich, H.

Se estudian las violaciones al Principio de Equivalencia en Teorías con Dilatón de Cuerdas. En estos modelos, algunas de las constantes fundamentales dependen del espacio y del tiempo. Se muestra que los experimentos de caída libre no tienen aún precisión como para poner límites a los parámetros de la teoría.

Líneas metálicas en protuberancias solares

NASA Astrophysics Data System (ADS)

Stenborg, G.; Rovira, M. G.; Mauas, P.

Para determinar cual de los modelos existentes de protuberancias solares explica mejor las observaciones, es necesario, no solo ajustar los perfiles de las líneas de hidrógeno, sino también utilizar perfiles de distintos metales. En este trabajo, utilizamos un código desarrollado especialmente para calcular el equilibrio estadístico de cualquier especie atómica, aplicándolo al cálculo de los perfiles de las líneas del Ca II, el Mg II y el He, para determinar cómo se comportan ante variaciones en los parámetros de los modelos de protuberancia (ancho, presión y temperatura centrales y número de hebras), y comparamos con las observaciones existentes para determinar que modelo las ajusta mejor.

PubMed

Defagó, Victor

2017-10-10

Introducción: La incorporación de la Clínica y la Imagenología permiten una mejor comprensión de la Anatomía. El objetivo de este trabajo es desarrollar un prototipo rápido en material sintético que replique detalles anatómicos para ser utilizado en la docencia y el entrenamiento quirúrgico en Pediatría.Material y Método: Presentación de caso: Paciente de un año de edad con síndrome de dificultad respiratoria. En el examen endoscópico se halló una compresión traqueal distal. La angiotomografía confirmó la presencia de una malformación vascular. Con la finalidad de analizar una conducta adecuada, se solicitó la confección de un prototipo rápido a escala 1:1 que simulara una condición idéntica a la topografía torácica del paciente, utilizando imágenes virtuales 3D almacenadas en formato DICOM.Técnica de generación de prototipo rápido: Se obtuvo una malla digital tridimensional y se generó el código "g" que se utilizó para controlar el hardware de producción. Se efectuó simulación digital y producción en material plástico (ABS) con técnica de deposición y fusión (MDF). Se validó el prototipo comparándolo con las mediciones testigos del modelo virtual en 3 D.Resultados y Discusión: El modelo replicó exactamente los defectos hallados en la tomografía y endoscopía, confirmando la presencia de la malformación vascular y su repercusión sobre el aparato respiratorio. El prototipo rápido muestra las estructuras internas y externas del cuerpo humano con máxima precisión permitiendo una visión topográfica de situaciones "normales o patológicas" que facilitaría la docencia y el entrenamiento del equipo quirúrgico para proponer un plan de tratamiento adecuado. Hay numerosas áreas de la medicina que se beneficiarían con este modelo que podría ser construído con diversos tipos de materiales de diferente flexibilidad y consistencia. Conclusiones: El prototipo rápido le da estado físico a las imágenes virtuales 3D, permitiendo la docencia y entrenamiento del equipo quirúrgico.

A Physics Model for Weight Loss by Dieting

DTIC Science & Technology

2012-09-01

de alimentos y líquidos) y su pérdida de energía (principalmente mediante la radiación y evaporación de agua). Al hacer dieta determinada, el peso...propio puede disminuir significativamente en un período tan corto como un par de docenas de semanas. Se desarrolla un modelo simple basado en la...física que describe un cambio en el peso con el tiempo. Las predicciones son razonables de acuerdo con los resultados televisados de los planes de dieta

Descripción de la zona de alta difusión en un modelo bidimensional para hojas de corriente

NASA Astrophysics Data System (ADS)

Montero, M. F.; Paola, C. A.; Platzeck, A. M.

Los modelos bidimensionales para describir hojas de corriente de alta simetría no suministran una descripción detallada de las regiones donde la difusión es considerablemente importante. Tal es el caso de los modelos desarrollados en la década del '60 por Sweet, Parker, Petschek y Sonnerup. En esta comunicación presentamos una solución de las ecuaciones MHD en el entorno del origen, construyendo series bidimensionales para todas las magnitudes físicas involucradas. Valiéndonos de la alta simetría y de las características del problema, logramos reducir el número de coeficientes a calcular. Utilizamos un programa autoconsistente para extender el cálculo a regiones vecinas con difusión moderada o despreciable.

Cómo calcular el índice UV

EPA Pesticide Factsheets

Información sobre cómo calcular el Índice ultravioleta (UV) a través de un modelo numérico que relaciona la intensidad de la radiación solar ultra violeta (UV) en la superficie terrestre con la concentración pronosticada de ozono estratosférico.

Modelo de accesibilidad de conceptos matematicos aplicados en el curso de Astronomia Descriptiva para estudiantes con impedimentos visuales en la UPR

NASA Astrophysics Data System (ADS)

Isidro Villamizar, Gloria Maria

Este estudio utiliza metodologia de investigacion cualitativa, con el proposito de describir, analizar y evaluar los procesos de diseno y desarrollo de un modelo de accesibilidad que consiste en estrategias de ensenanza de las matematicas para estudiantes con impedimentos visuales matriculados en el curso de Astronomia Descriptiva en la UPR. Se utilizaron las siguientes estrategias para recopilar la informacion, 1) reflexiones de la investigadora en el proceso de diseno y desarrollo de las lecciones adaptadas, que se registraron en un diario reflexivo. 2) entrevista semiestructurada luego de haber trabajado las lecciones de aprendizaje adaptadas con los participantes. 3) observaciones y notas de la investigadora del trabajo de los participantes. Para obtener la informacion de los participantes se obtuvo los permisos institucionales necesarios; se seleccionaron los participantes y se validaron los instrumentos; se realizo el desarrollo de las lecciones adaptadas con los participantes; y finalmente, se analizo la informacion obtenida. El diseno de las lecciones de aprendizaje adaptadas se hizo siguiendo las recomendaciones curriculares de los temas de matematicas aplicados en el curso de Astronomia Descriptiva realizado por la investigadora durante su semestre de internado. El testimonio de las voces de los participantes se obtuvo del proceso de desarrollo de las lecciones de aprendizaje adaptadas de temas seleccionados de conceptos matematicos requeridos en el curso de Astronomia Descriptiva y de la entrevista semiestructurada con los participantes, luego de haber trabajado las lecciones de aprendizaje. Para el desarrollo de las lecciones de aprendizaje, se utilizaron materiales tactiles adaptados, materiales tactiles disenados y materiales disponibles comercialmente. Los textos de las lecciones se imprimieron en tinta y en Braille. Se exhorta a disenar y desarrollar estrategias de ensenanza accesibles, considerando como recursos para evaluar su efectividad a personas con impedimentos visuales. El utilizar estrategias de aprendizaje accesibles de acuerdo a las necesidades individuales de los estudiantes, contribuye para que los estudiantes con impedimentos visuales descubran, exploren, investiguen y formulen sus propias conclusiones durante su proceso de aprendizaje.

Discos de acreción circumplanares: Modelo de Co-acreción

NASA Astrophysics Data System (ADS)

Parisi, M. G.; de Elía, G.

Los discos de acreción circumplanetarios precursores de los satélites regulares de los planetas gigantes, se pueden formar por cuatro mecanismos (Pollack y otros, 1991, In Uranus, Bergtralh, Miner y Mattews, Eds., p. 469, Univ. de Arizona Press, Tucson). En este trabajo estudiamos uno de tales mecanismos: el Modelo de Co-acreción. En dicho modelo, el disco circumplanetario se forma a partir de las colisiones mutuas entre planetesimales dentro de la esfera de Hill del planeta durante el proceso de formación planetaria. Realizamos un modelo semi-analítico para calcular la masa del disco y compararla con la masa requerida para formar los satélites regulares de los planetas gigantes. Hemos obtenido una cota superior para la masa del disco que resulta inferior a la masa de los satélites más grandes de los planetas gigantes. En principio, estos resultados permitirían descartar el modelo de co-acreción como uno de los procesos que podrían dar lugar a la formación de los satélites regulares. Estos resultados permiten obtener restricciones en el escenario de formación planetaria y en los mecanismos de formación de sistemas de satélites.

Comportamiento del Helio en estrellas químicamente peculiares

NASA Astrophysics Data System (ADS)

Malaroda, S. M.; López García, Z.; Leone, F.; Catalano, F.

Las estrellas químicamente peculiares (CP) se caracterizan por tener deficiencias y sobreabundancias de algunos elementos químicos de hasta 106 veces la abundancia solar. Además presentan variaciones en las líneas espectrales. Se piensa que ello se debe a que los campos magnéticos presentes en este tipo de estrellas son principalmente dipolares, con un eje de simetría diferente del eje de rotación. La distribución de los elementos sobreabundantes y deficientes no es homogénea sobre la superficie estelar y las variaciones observadas serían una consecuencia directa de la rotación estelar. Entre los elementos con abundancia anómala se encuentra el Helio, cuyas líneas tienen intensidades que no son consistentes con una abundancia normal, que no puede ser determinada del modo usual, o sea, considerando una atmósfera con composición solar. Con el fin de determinar la abundancia de este elemento, se inició un estudio de estrellas anómalas de Helio, Hew y He strong. Además se determinarán las abundancias de otros elementos anómalos como ser el Si, Cr, Mg, Mn y Fe. Las mismas se determinan del modo tradicional, o sea: a) medida de los anchos equivalentes de las líneas de los distintos elementos analizados; b) adopción de la temperatura efectiva, gravedad y abundancia del Helio; c) cálculo del modelo de atmósfera d) comparación con las observaciones y reinicio de un proceso iterativo hasta lograr un acuerdo entre todos los parámetros analizados. Las observaciones se llevaron a cabo en el Complejo Astronómico El Leoncito. Se observaron setenta y ocho estrellas anómalas de Helio. En este momento se está procediendo a calcular las abundancias correspondientes a los distintos elementos químicos. Para ello se hace uso de los modelos de Kurucz, ATLAS9. Los cálculos NLTE de las líneas de Helio se llevan a cabo con el programa MULTI y se compararán con los realizados con el programa WIDTH9 de Kurucz (LTE), con el objeto de resaltar la importancia de los efectos NLTE.

Seguridad del paciente en Radioterapia Intraoperatoria: Impacto de los elementos controlados por el Radiofisico

NASA Astrophysics Data System (ADS)

Tarjuelo, Juan Lopez

Introduccion: En la administracion de la radioterapia intervienen profesionales y equipos de tratamiento, por lo que existe el riesgo de error y se precisa que dicho equipamiento funcione conforme a lo esperado. A los radiofisicos les corresponde participar en las actividades de garantia o aseguramiento de la calidad, incluyendo el control de calidad de los equipos, y en la evaluacion de los riesgos asociados. La radioterapia intraoperatoria (RIO) es una tecnica radioterapica de intensificacion de dosis, altamente selectiva, dirigida a volumenes anatomicos restringidos durante el tratamiento quirurgico oncologico, basada en la administracion de una dosis absorbida alta por medio de un haz de electrones tras el examen visual directo del lecho tumoral. Como incorporar los ultimos avances en el refuerzo de la seguridad en radioterapia es una tarea ambiciosa y compleja, resulta mas concreta y de inmediata aplicacion su introduccion en la RIO. El objetivo es analizar los elementos que reducen los riesgos y aumentan la seguridad en la RIO y su dosimetria, y valorar la funcion del radiofisico en esta labor. Material y metodos: Se emplearon el planificador Radiance de GMV y el acelerador lineal de los tratamientos de RIO Elekta Precise, controlado con el verificador diario de haces Daily QA Check 1090 y medido con las camaras de ionizacion PPC 40, FC65-G y FC65-P de PTW-Freiburg, a su vez verificadas con fuentes radiactivas adecuadas de estroncio-90 modelos CDP y CDC de IBA Dosimetry. Se realizo un analisis de modos de fallo y efectos (failure mode and effect analysis, FMEA) con el fin de identificar los elementos que forman la RIO y aplicar las herramientas necesarias para la minimizacion de los riesgos y la mejora de la seguridad en la tecnica. Se estudiaron las verificaciones diarias de dicho acelerador Precise con el control estadistico de procesos (statistical process control, SPC) y se simularon intervenciones para devolverlo al estado llamado en control. El SPC tambien se uso para estudiar la estabilidad de las camaras de ionizacion mencionadas. Se realizo la dosimetria in vivo en 45 pacientes con MOSFET reforzados mobile TN-502RDM-H, pelicula radiocromica Gafchromic MD-55-2, y se elaboro un modelo teorico para explicar los datos. Por ultimo, al precisarse el uso en RIO de la simulacion virtual y del calculo de la dosis absorbida en el paciente virtual, se ha ilustrado este apartado con la aceptacion y el estado de referencia inicial del planificador de tratamientos modulados con calculo de Monte Carlo Elekta Monaco. Para ello se utilizaron la camara de ionizacion TW31016-0104 y la matriz seven29 de PTW-Freiburg, pelicula radiocromica Gafchromic EBT-2, y diferentes maniquies. Resultados: El FMEA identifico 57 modos de fallo y efectos potenciales. No se experimentaron sucesos relativos a una administracion inadecuada de la dosis absorbida. Se identificaron las revisiones dobles y por un par como claves para reducir los riesgos asociados al equipo de profesionales involucrado en la RIO. Se identificaron tambien oportunidades de mejora con el uso de la automatizacion y el enclavamiento. En cuanto al SPC, los indices de capacidad del proceso abarcaron de 1,6 a 9,3 para un nivel de especificaciones del +/-2%. Las intervenciones simuladas alcanzaron del 2% al 34% de las sesiones de medida. Las camaras de ionizacion Farmer derivaron en direcciones opuestas en un periodo de 6 anos; aunque ello no se aprecio en los informes de calibracion del laboratorio acreditado. No derivo la camara PPC-40. En la dosimetria in vivo, las medidas de los MOSFET no se desviaron significativamente de las medidas con pelicula. Los valores centrales de las dosis absorbidas quedaron entre la dosis absorbida prescrita y la maxima, con lo que indicaron un tratamiento correcto del lecho tumoral. Las anchuras de los intervalos de confianza de las dosis absorbidas esperadas segun el modelo teorico al nivel del 95% abarcaron del 8,6% al 14,7%. Las verificaciones de Monaco resultaron satisfactorias excepto en el caso de la transferencia de datos, que obligo a cambiar el flujo de trabajo. Conclusiones: El FMEA es crucial para priorizar las intervenciones reductoras del riesgo. Tipos diferentes de procesos fallidos se pueden eliminar o paliar con tipos diferentes de tales intervenciones. El SPC puede evaluar la variabilidad inherente del procedimiento monitorizador de haces de electrones, indica cuando intervenir para devolver un proceso al estado de control y si un proceso es capaz con respecto a unas especificaciones o requisitos establecidos. Es viable realizar dosimetria in vivo con un acelerador convencional fijo y obtener resultados satisfactorios en cada localizacion estudiada a pesar de su variabilidad. El modelo teorico desarrollado puede describir con exito resultados globales, aunque no puede explicar todos los datos experimentales. Se ha mostrado que un planificador puede funcionar correctamente en condiciones de laboratorio o trabajando solo; pero puede fallar cuando se conecta con otros equipos de radioterapia. Todos estos aspectos presentados y evaluados aqui constituyen competencias actuales o futuras, y deseables, de los radiofisicos, tanto en el campo de la RIO como en la extension a la radioterapia en su conjunto.

Condiciones Físicas en Nebulosas Gaseosas

NASA Astrophysics Data System (ADS)

Luridiana, V.

1999-03-01

El presente trabajo se ha enfocado a determinar y entender las condiciones físicas en una variedad de objetos nebulares, prestando particular atención al problema de la determinación de las abundancias químicas. Para este fin, hemos utilizado métodos analíticos en algunos casos, y modelos numéricos de fotoionización en otros. El objetivo general del trabajo es proveer de una visión amplia de las herramientas teórico-observacionales que se utilizan para la determinación de la estructura de temperatura y densidad de las regiones fotoionizadas, poniendo en evidencia posibles fuentes de errores sistemáticos y sus consecuencias para la determinación de las abundancias químicas, y proponiendo métodos para corregirlos. Los resultados principales de este trabajo est´n listados a continuación: a) Se discute el problema de la discrepancia entre T(C III) y T(O III) en las nebulosas planetarias, y se muestra como tal discrepancia implica probablemente la presencia de fluctuaciones de temperatura. Debido a que la temperatura de O++ es muy afectada por fluctuaciones de temperatura, se recomienda usar la temperatura de C++ para determinar la abundancia de carbono. b) Presentamos dos nuevos métodos para determinar la temperatura electrónica en nebulosas planetarias, basados en la medición de las intensidades de las líneas de He I. Las temperaturas que se obtienen a partir de estos métodos son menores que aquellas que se obtienen a partir de las líneas de [O III], implicando la presencia de fluctuaciones espaciales de temperatura. Despreciando las fluctuaciones de temperatura, se obtienen valores sesgados de las abundancias químicas. Determinamos las abundancias en las nebulosas planetarias de tipo I de algunos de los elementos más importantes, tomando en cuenta las fluctuaciones de temperatura. c) Presentamos modelos numéricos de las dos regiones H II extragalácticas gigantes NGC 2363 y NGC 5461. Con el modelaje numérico, pretendemos acotar las carácteristicas principales de las nubes ionizadas (distribución espacial del gas, estructura de ionización y de temperatura) y de los cúmulos ionizantes (función inicial de masa, historia de formación estelar, edad). En ambos casos, mostramos que con modelos numéricos calculados para el valor de metalicidad que se determina a partir de la temperatura de [O III], no es posible reproducir el espectro de emisión observado, y que para reproducir las restricciones más robustas es necesario subir la metalicidad de los modelos por un factor de 2. Esto constituye una fuerte indicación en favor de la presencia de fluctuaciones de temperatura. d) Para poder comparar los modelos numéricos con los datos observacionales. mostramos la importancia de corregir las predicciones de los modelos por el sesgo introducido por el tamaío finito de la rendija.

Dinámica de pulsares jóvenes

NASA Astrophysics Data System (ADS)

Allen, M. P.; Horvath, J. E.

La observación detallada de los pulsos en varios pulsares jóvenes (τ < 105 yr) permitió detectar varios aumentos en la frecuencia de emisión gliches con cambios permanentes en Δ {˙ Ω} / {˙ Ω}. A través de las ecuaciones de movimiento se investiga, utilizando parametrizaciones simples, la hipótesis de que el ángulo entre Ω y el dipolo magnético M sea responsable de ese comportamiento. Se derivan curvas analíticas para la evolución de Ω (t) y se estudia la posibilidad de describir un conjunto de observables (incluyendo el braking index n) con estos modelos.

Evolución de estrellas enanas blancas de Helio de masa baja e intermedia

NASA Astrophysics Data System (ADS)

Althaus, L. G.; Benvenuto, O. G.

Numerosas observaciones realizadas particularmente en los últimos dos años parecen confirmar que las enanas blancas (EB) de helio de masa baja e intermedia son el resultado de la evolución de sistemas binarios cercanos. Con el objeto de realizar una adecuada interpretación de estos objetos son necesarios modelos de EBs de helio lo más detallado posibles. En este estudio presentamos cálculos detallados de la evolución de EBs de helio con masas entre M=0.1Msolar y M=0.5Msolar a intervalos de 0.05Msolar . Para ello, hemos tenido en cuenta los efectos de temperatura finita mediante un código de evolución estelar lo más actualizado posible. En particular, el transporte de energía es descripto en el marco del nuevo modelo para la convección turbulenta desarrollado por Canuto - Mazzitelli. Además hemos considerado la nueva ecuación de estado para plasmas de helio de Saumon et al. y nuevas opacidades radiativas OPAL. Las pérdidas por neutrinos fueron asimismo tenidas en cuenta. Excepto para las EBs más masivas, nuestros modelos iniciales están ubicados en las cercanías de la correspondiente línea de Hayashi para configuraciones de helio. Nuestros resultados muestran que existe una región prohibida en el diagrama observacional HR donde ninguna EB de helio puede encontrarse. Dicha región es para log{(L/Lsolar )}>= -0.25 and log{Teff} >= 4.45. Hemos encontrado también que los tracks evolutivos en el diagrama HR en el dominio de alta luminosidad (pre - EB) son fuertemente afectados por la eficiencia convectiva y que las pérdidas por neutrinos son importantes en los modelos más masivos. Finalmente hemos analizado la estructura de la zona convectiva externa encontrando que la teoría de Canuto - Mazzitelli conduce a un perfil convectivo muy diferente del dado por cualquier versión de la popular teoría de la mixing length. Si bién este comportamiento es decisivo en el contexto de las inestabilides pulsacionales, los radios y gravedades superficiales de los modelos no son afectados al incluir la nueva teoría de convección.

Elastoplasticidad anisotropa de metales en grandes deformaciones

NASA Astrophysics Data System (ADS)

Caminero Torija, Miguel Angel

El objetivo de este trabajo es el desarrollo de modelos y algoritmos numericos que simulen el comportamiento del material bajo estas condiciones en el contexto de programas de elementos finitos, dando como resultado predicciones mas precisas de los procesos de conformado y deformacion plastica en general. Para lograr este objetivo se han desarrollado diversas tareas destinadas a mejorar las predicciones en tres aspectos fundamentales. El primer aspecto consiste en la mejora de la descripcion del endurecimiento cinematico anisotropo en pequenas deformaciones, lo cual se ha realizado a traves de modelos y algoritmos implicitos de superficies multiples. Ha sido estudiada la consistencia de este tipo de modelos tanto si estan basados en una regla implicita similar a la de Mroz o en la regla de Prager. Ademas se han simulado los ensayos de Lamba y Sidebottom, obteniendo, en contra de la creencia general, muy buenas predicciones con la regla de Prager. Dichos modelos podrian ser extendidos de forma relativamente facil para considerar grandes deformaciones a traves de procedimientos en deformaciones logaritmicas, similares a los desarrollados en esta tesis y detallados a continuacion. El segundo aspecto consiste en la descripcion de la anisotropia elastoplastica inicial. Esto se ha conseguido mediante el desarrollo de modelos y algoritmos para plasticidad anisotropa en grandes deformaciones, bien ignorando la posible anisotropia elastica, bien considerandola simultaneamente con la anisotropia plastica. Para ello ha sido necesario desarrollar primero un nuevo algoritmo de elastoplasticidad anisotropa en pequenas deformaciones consistentemente linealizado y sin despreciar ningun termino, de tal forma que se conserve la convergencia cuadratica de los metodos de Newton. Este algoritmo en pequenas deformaciones ha servido para realizar la correccion plastica de dos algoritmos en grandes deformaciones. El primero de estos algoritmos es una variacion del clasico algoritmo de Eterovic y Bathe para incluir la posibilidad de plasticidad anisotropa con endurecimiento mixto. Este primer algoritmo esta restringido a casos de isotropia elastica. La isotropia elastica es una hipotesis bastante habitual en plasticidad anisotropa y tiene la ventaja de que permite el uso de formulaciones mixtas u/p. El segundo algoritmo, mas complejo y general, incluye la posibilidad de elasticidad anisotropa, plasticidad anisotropa y endurecimiento mixto. Este algoritmo supone una contribucion importante ya que esta basado en hipotesis comunmente aceptadas y utilizadas en elastoplasticidad isotropa: descomposicion multiplicativa del gradiente de deformaciones en parte elastica y parte plastica, descripcion hiperelastica sencilla en funcion de deformaciones logaritmicas e integracion exponencial que conserva el volumen. Ademas, la estructura final del algoritmo es modular y relativamente sencilla, consistiendo en un pre- y un postprocesador geometrico y una correccion plastica realizada en pequenas deformaciones. El algoritmo esta consistentemente linealizado para conservar la convergencia cuadratica asintotica de los metodos de Newton y la forma final que toma dicha linealizacion es similar al caso de isotropia elastoplastica implementado; consiste en el modulo tangente algoritmico de pequenas deformaciones sobre el que se aplica una transformacion para convertirlo en el de grandes deformaciones. Todos estos modelos han sido implementados en un codigo propio de elementos finitos denominado DULCINEA, el cual tiene formulaciones lagrangianas totales y actualizadas para grandes deformaciones. Una de las tareas necesarias para poder realizar las simulaciones, ha sido el estudio e implementacion de diferentes elementos que no sufran el bloqueo volumetrico severo que se observa en formulaciones estandar basadas en desplazamientos. Este bloqueo se debe a la condicion de quasi-incompresibilidad que imponen los modelos de plasticidad desviadores y consiste en una respuesta exageradamente rigida de la solucion obtenida por el metodo de los elementos finitos estandar. Entre los elementos implementados cabe destacar el basado en la formulacion mixta u/p, que contiene una interpolacion adicional de grados de libertad de presion. Estos grados de libertad adicionales habitualmente son internos al elemento en mecanica de solidos. En este trabajo se ha desarrollado e implementado en DULCINEA una familia de elementos tridimensionales mixtos en grandes deformaciones que incluye el caso particular BMIX 27/27/4, basado en la formulacion u/p, constituido por 27 nudos, con 27 puntos de integracion estandar y 4 grados de libertad de presiones, y que pasa la condicion Inf-Sup o de Babuska-Brezzi. Sin embargo, se ha observado que la formulacion u/p presenta ciertas limitaciones bajo las hipotesis conjuntas de anisotropia elastica y anisotropia plastica. (Abstract shortened by UMI.)

Análisis fotométrico-espectroscópico de un par de binarias en NGC 3532

NASA Astrophysics Data System (ADS)

Gramajo, L.; González, J. F.

Presentamos el informe de avance de un proyecto que apunta a la determinación de masas y radios de precisión en estrellas tempranas de cúmulos abiertos mediante el análisis fotométrico-espectroscópico de sistemas binarios detached con baja rotación. Con ello se pretende determinar el estado evolutivo de estas estrellas y confrontar su estructura con modelos estelares teóricos con distinto grado de ``overshooting". Los primeros objetos seleccionados son dos sistemas binarios de espectros dobles (BDA27 y BDA363) detectados en el cúmulo NGC 3532. Presentamos la órbita espectroscópica obtenida para la binaria eclipsante BDA27, para la cual obtuvimos un período de 4.29 días y una razón de masas q=0.62. Derivamos sus parámetros absolutos preliminares usando nuestra curva de velocidad y datos fotométricos existentes en la literatura, y presentamos estimas del alcance de nuestros resultados una vez que hayamos completado nuestras observaciones con nuevas curvas de luz.

Produccion Gaseosa del Cometa Halley: Erupciones Y Fotodisociacion del Radical OH

NASA Astrophysics Data System (ADS)

Silva, A. M.; Mirabel, I. F.

1990-11-01

RESUMEN:En este trabajo informamos la detecci6n de 20 erupciones en la li'nea de =18cm (1667MHz) del radical OH en el Cometa Halley.Las observaciones incluyen todos los monitoreos existentes y se extienden desde 120 dias antes del perihelio hasta 90 dias despues.Se detectan bruscos crecimientos en el flujo medido,hasta un factor 1O,seguidos por decaimientos lentos asociados con la fotodisociaci6n del OH. Se obtuvieron valores para el tiempo de vida fotoquimico del OH y del H2O basandose en el modelo desarrollado previamente por Silva(1988). Esos tiempos de vida estan de acuerdo con predicciones teoricas y con las observaciones en el Ultravioleta, y los resultados, los que son fuertemente dependientes de la velocidad heliocentrica del Coineta (variando hasta un factor 6), han sido calculados para varios rangos de velocidad entre +28 y -28 km/seg. Key wo'L :

[Not Available].

PubMed

Fehrman-Rosas, Pamela; Delgado-Sánchez, Claudia; Fuentes-Fuentes, Jessica; Hidalgo-Fernández, Andrea; Quintana-Muñoz, Carol; Yunge-Hidalgo, Wilma; Fernández-Godoy, Eloina; Durán-Agüero, Samuel

2016-06-30

Objetivo: asociar patrones alimentarios con la autopercepción del estado nutricional en estudiantes universitarios chilenos de Nutrición y Dietética.Material y métodos: estudio transversal en el que se evaluó a 634 estudiantes de Nutrición y Dietética, de los cuales un 86,4% eran mujeres. A cada alumno se le mostraron siete modelos anatómicos correspondientes a valores de índice de masa corporal (IMC) de 18, 22, 25, 27, 30, 35 y 40 kg/m2. Cada estudiante debía elegir el modelo con el que mejor se identificaba. Posteriormente, se realizó la evaluación antropométrica, se calculó el IMC real comparándolo posteriormente con el IMC percibido, y finalmente se le aplicó una encuesta alimentaria.Resultados: se observa que los sujetos que sobreestiman su peso presentan un menor porcentaje de cumplimiento en el consumo de frutas y verduras al día; en cambio, el mayor porcentaje de sujetos que sigue las recomendaciones se encuentra en el grupo que se ve igual. Hay unaasociación entre una buena percepción de la imagen corporal y el consumo de 3 o más porciones de frutas al día OR = 0,554 (IC 95%; 0,360-0,852), 2 o más porciones de verduras al día OR = 0,438 (IC 95%; 0,283-0,678) y un consumo de alcohol menor de una vez a la semanaOR = 0,451 (IC 95%; 0,270-0,752).Conclusión: los estudiantes que registran una ingesta adecuada de verduras y frutas autodefinen su alimentación como saludable e ideal y tienden a autopercibirse coherentemente en relación con su estado nutricional; además, estos sujetos son los que presentan una ingesta menor de alimentos poco saludables.

Evolución Dinámica de Cúmulos Estelares Abiertos

NASA Astrophysics Data System (ADS)

de La Fuente Marcos, R.

Las estrellas que observamos no se formaron aisladamente, sino que lo hicieron en grupos o cúmulos. Estos sistemas estelares recibenel nombre de cúmulos estelares abiertos o galácticos cuando están constituidos por estrellas de la Población I. Los cúmulos abiertos se localizan preferentemente en el plano galáctico, y en muchos de ellos está teniendo lugar aún una activa formación estelar. El propósito principal de esta tesis doctoral es el estudio de la evolución dinámica de estos sistemas estelares por medio de simulaciones numéricas y de la comparación de sus resultados con datos observacionales. Con este fin se analizan los efectos que, sobre la dinámica de los cúmulos, ejercen varios fenómenos de interés astrofísico tales como el campo gravitatorio galáctico, la pérdida de masa causada por la evolución estelar y la presencia de binarias primordiales. En este trabajo se presentan los resultados de más de un centenar de modelos de cúmulos, con poblaciones comprendidas en el intervalo [100, 10.000] estrellas, calculados con NBODY5, un programa estándar en el campo de la Dinámica Estelar Experimental. De los mismos se deduce que el mecanismo principal que rige la dinámica de los cúmulos abiertos es la evolución estelar de su distribución de masas, encontrándose un comportamiento diferencial fuertemente dependiente de la población inicial del cúmulo. Los mecanismos responsables de la desintegración de los cúmulos abiertos son analizados en detalle, proponiéndose un modelo analítico que ajusta razonablemente los resultados de las simulaciones. Además, y con el fin de explicar el elevado número de sistemas múltiples observados en cúmulos abiertos, se estudian los efectos que, sobre los mismos, ejerce la presencia de una cierta fracción de binarias primordiales. El papel de las binarias tambiín depende de la riqueza del cúmulo y sus efectos se interrelacionan con aquellos debidos a la evolución estelar. Por último, se aborda la posibilidad de construir diagramas de Hertzsprung-Russell teóricos a partir de las simulaciones y compararlos con datos procedentes de cúmulos abiertos reales.

Confirmation Tests of Hot and Cold Artillery Shell Drawing Operations

DTIC Science & Technology

1979-05-01

internally, to increase the production rate. The flow stress of the deforming materials under hot drawing con - ditions is a function of strain rate...of the press, and its cable was hooked to the slider of the press ram. The amplified output of the displacement transducer was con - cected to the...present investigation, tests were conducted with both con - ventional conical and streamlined die designs to evaluate the mathematical models of the

Knowledge and Beliefs of Breast Cancer Among Elderly Puerto Rican Women.

DTIC Science & Technology

1995-10-01

nuevos modelos * conceptuales e hip6tesis de investigaci6n que pueden ser cornprobadas posteriorrnente con un ni~mero mayor de sujetos (O’Brien 1993...de mama. 1. Las mujeres que han tenido cdncer de mama tienen m6.s Riesgos posibilidad de desarrollarlo de nuevo . 2. Las mujeres que tuvieron su primer...4 A. Instrucciones Generales .......................... 4 B. Responsabilidades de la entrevistadora ........... 6 C. Materiales a ser llevados al

Nuevos fenómenos en erupciones cometarias

NASA Astrophysics Data System (ADS)

Silva, A.

Se discuten aquí tres procesos físicos novedosos encontrados en la actividad de cometas: 1) El rol de una distribución de granos de hielo como fuente extendida de H2O en la coma, 2) El efecto de una discontinuidad en el plasma cometario, llamada Cometopausa, sobre la excitación del radical OH , y 3) La actividad por erupciones a grandes distancias heliocéntricas (r > 5 AU). Con respecto a 1) y 2), se presentan modelos que ajustan bien con las observaciones. En cuanto a 3), se presentan explicaciones posibles al fenómeno, y se trata el interesante caso de Chirón 2060, basándose en observaciones propias tomadas desde el CASLEO y datos anteriores.

Cúmulos globulares como trazadores de bimodalidad estelar en galaxias cD

NASA Astrophysics Data System (ADS)

Forte, J. C.

Se muestra que tanto la forma de los perfiles de brillo como de color observados en dos galaxias arquetípicas de tipo cD (NGC 1399 y NGC 4486) son compatibles con la presencia de poblaciones estelares bi-modales que comparten la misma distribución espacial y composición química de las familias dominantes de cúmulos globulares asociadas con ellas. El modelo resultante también predice una variación de la frecuencia específica de los cúmulos como función del radio galactocéntrico. Se discute este resultado en el contexto de una variedad de escenarios astrofísicos que intentan describir la formación de galaxias cD.

Uso Del Condón en Adolescentes Nahuas, un Modelo Explicativo.

PubMed

Tirado, María de Los Ángeles Meneses; Benavides-Torres, Raquel A; Navarro, Sergio Meneses; de la Colina, Juan Antonio Doncel; Rodríguez, Dora Julia Onofre; Hernández, Francisco Javier Baéz

2018-03-01

En México, la población indígena supera los siete millones de habitantes, en Puebla el grupo más representativo es el Náhuatl. Sin embargo, las condiciones de vida, salud, educación y transporte son precarias para esta población. En los adolescentes, las responsabilidades como el matrimonio, la familia y los compromisos ante la comunidad, favorecen conductas de riesgo sexual que dificultan su desarrollo económico, social y reproductivo. El objetivo fue proponer un modelo explicativo del uso del condón en adolescentes nahuas. Método. Bajo el marco de la teoría social cognitiva, el concepto de valores culturales de Leininger y el proceso de la sustracción teórica, se desarrolló este artículo. Se muestran las relaciones del modelo con las proposiciones y los factores que influyen en el uso del condón para este grupo específico. Finalmente, el modelo explica las variables de interés, los niveles de abstracción y las relaciones entre sí en el contexto náhuatl. El siguiente paso será implementar los indicadores empíricos para conocer el grado de influencia de los factores personales y ambientales hacia el uso del condón en adolescentes nahuas. Resultados que aportarán información para el desarrollo del conocimiento en enfermería y la reducción de riesgo sexual de esta población.

órbitas: caos en familia

NASA Astrophysics Data System (ADS)

Carpintero, D. D.

Durante los últimos años, ha ido adquiriendo importancia la descripción dinámica de un sistema estelar a través de su estructura orbital, complementando el tradicional uso de la función de distribución en el espacio fase. El desarrollo de esta nueva concepción condujo, con el tiempo, a la conclusión de que las órbitas caóticas juegan un importante papel dinámico en modelos realistas de galaxias. Sin embargo, la determinación de la caoticidad de una órbita, o de la familia regular a la cual pertenece, siguió siendo una tarea artesanal. Nuevos métodos de clasificación fueron surgiendo con el tiempo; hoy en día, se cuenta con métodos que permiten determinar automáticamente el contenido orbital de cualquier potencial arbitrario que se desee para modelar una galaxia, o incluso determinar la familia de una órbita sin siquiera conocer el potencial en el que está sumergida.

Analysis of groundwater discharge with a lumped-parameter model, using a case study from Tajikistan

NASA Astrophysics Data System (ADS)

Pozdniakov, S. P.; Shestakov, V. M.

A lumped-parameter model of groundwater balance is proposed that permits an estimate of discharge variability in comparison with the variability of recharge, by taking into account the influence of aquifer parameters. Recharge-discharge relationships are analysed with the model for cases of deterministic and stochastic recharge time-series variations. The model is applied to study the temporal variability of groundwater discharge in a river valley in the territory of Tajikistan, an independent republic in Central Asia. Résumé Un modèle global de bilan d'eau souterraine a été développé pour estimer la variabilité de l'écoulement par rapport à celle de la recharge, en prenant en compte l'influence des paramètres de l'aquifère. Les relations entre recharge et écoulement sont analysées à l'aide du modèle pour des variations des chroniques de recharge soit déterministes, soit stochastiques. Le modèle est appliquéà l'étude de la variabilité temporelle de l'écoulement souterrain vers une rivière, dans le Tadjikistan, une république indépendante d'Asie centrale. Resumen Se propone un modelo de parámetros concentrados para realizar el balance de aguas subterráneas, el cual permite estimar la variabilidad en la descarga con respecto a la variabilidad en la recarga, en función de los parámetros que caracterizan el acuífero. Las relaciones entre recarga y descarga se analizan con el modelo para distintos casos de series temporales de recarga, tanto deterministas como estocásticas. El modelo se aplica al estudio de la variabilidad temporal de la descarga en un valle aluvial de Tadyikistán, una república independiente del Asia Central.

La binaria LSS 3074 y su entorno: ?`una nueva asociación OB?

NASA Astrophysics Data System (ADS)

Niemela, V.; Morrell, N.; Corti, M.

En este trabajo presentamos un nuevo análisis orbital de LSS~3074, junto con tipos espectrales y velocidades radiales de estrellas que podrían constituir con ella una nueva asociación OB. La estrella O4f LSS3074 fue descubierta como binaria espectroscópica de corto período y líneas dobles por Morrell & Niemela (1990, ASP Conf. Ser. 7, 57). Posteriormente, Haefner et~al.(1994, IBVS 3969) encontraron variaciones fotométricas, estimando una inclinación orbital entre 50o y 55o. Teniendo en cuenta la importancia de obtener valores empíricos para las masas de estrellas O tempranas, y considerando la gran dispersión existente entre los valores observados y su discrepancia con los predichos por los modelos teóricos, hemos obtenido nuevas observaciones espectroscópicas de este sistema, con el propósito de mejorar los elementos orbitales derivados en la solución preliminar. Además, como las estrellas O tempranas suelen formar parte de cúmulos y asociaciones OB, hemos llevado a cabo una investigación espectroscópica de varias estrellas tempranas que podrían estar físicamente relacionadas con LSS~3074.

Componente de la envoltura en la discontinuidad de Balmer de estrellas Be

NASA Astrophysics Data System (ADS)

Rohrmann, R. D.; Cidale, L.

En modelos de atmósferas en expansión de estrellas Be se estudia la contribución al salto de Balmer de una envoltura circunestelar. Se busca relacionar el salto de Balmer fotosférico y el salto de Balmer originado en la envoltura con los distintos parámetros de la atmósfera (dimensión de la cromosfera, ley de expansión, tasa de pérdida de masa, etc.).

Memorias del tercer simposio internacional sobre economía, planificación, y políticas de los incendios forestales: problemas y enfoques comunes

Treesearch

Armando González-Cabán

2009-01-01

Estas memorias resumen el resultado de un simposio diseñado para discutir los problemas actuales que confrontan las agencias con responsabilidad para la proteccion contra incendios forestales a nivel federal y estadual en los EE.UU., al igual que agencias en la comunidad internacional. Los temas discutidos en el simposio incluyen economía del fuego, teoría y modelos...

Difusión de Arnold en un modelo simple

NASA Astrophysics Data System (ADS)

Cincotta, P. M.; Nuñez, J. A.; Miloni, O.

Investigadores como Merritt, Valluri, Pfenniger o Contopoulos (por citar los más relevantes) consideran seriamente la hipótesis que la difusión de Arnold juega un rol importante en la evolución dinámica de los sistemas estelares y planetarios. Sin embargo no existe ninguna evidencia. El mayor problema para investigar fenómenos como éste es que uno debe estudiar numéricamente sistemas multidimensionales (más de dos grados de libertad) y visualizar de alguna manera el espacio de fases (más de cuatro dimensiones). Más complicado aún es el caso de difusión de Arnold, donde deben considerarse tiempos de movimiento extremadamente largos y tratar con parámetros exponencialmente pequeños. El propósito de este trabajo es estudiar, en un modelo simple 3D, la existencia o no de difusión de Arnold mediante experimentos numéricos y estimaciones analíticas. Siguiendo los trabajos de Cincotta (2000) y Cincotta, Nuñez y Simo (2000), aquí se pretende ``visualizar" la difusión y, a la vez, determinar la escala de tiempo en la que ésta se podría manifestar. Este trabajo es el escalón inicial para luego abordar este problema en modelos.

Determinacion del error sistematico del momentum de muones producidos por interacciones neutrino-nucleon en el detector MINER$$\

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diaz Bautista, Gonzalo A.

El Modelo Estandar describe todas las partculas observadas en el naturaleza hasta el momento as como las caractersticas que gobiernan a las interacciones fundamentales entre ellas. En especial es posible identicar a las interacciones electromagnetica y debil, las cuales bajo determinadas condiciones de temperatura y energa pueden ser descritas a traves de una sola teora que engloba a ambas. A esta teora se le denomina electrodebil y tiene como nalidad caracterizar las propiedades de la interaccion maniesta a partir de la mezcla de las interacciones electromagnetica y debil, la que tambien lleva como nombre interaccion electrodebil. Particularmente, los neutrinos sonmore » de especial interes ya que, por un lado, interactuan por medio de la interaccion debil muy raramente en comparacion con otras partculas y, por el otro, no son acertadamente descritos por el Modelo Estandar. Por medio de observaciones experimentales que demostraban que los neutrinos cambian de sabor al propagarse, fenomeno llamado oscilaciones de neutrinos, se pudo llegar a la conclusion de que la implicancia de este fenomeno da como consecuencia que los neutrinos efectivamente s tienen masa, algo que entra en contradiccion con la descripcion inicial del Modelo Estandar, el cual los describe como partculas sin masa. Es de esta manera que las oscilaciones de neutrinos han sido y siguen siendo en la actualidad objeto de interes en la Fsica de Altas Energas tanto teorica como experimental. A n de poder realizar mediciones precisas de oscilaciones de neutrinos, los experimentos encargados de estas mediciones deben tratar de reducir sus incertidumbres en lo posible. Una de estas proviene de la caracterizacion de las secciones de choque de los neutrinos cuando interactuan con la materia, particularmente los nucleones al interior de los nucleos atomicos. El experimento MINERA esta orientado, entre otras cosas, a hacer una correcta caracterizacion de secciones de choque neutrino-nucleon por medio del estudio de un tipo especco de interaccion denominado corriente cargada, cuyas partculas de estado nal incluye hadrones y, principalmente, muones. La precision en los resultados de secciones de choque esta sujeta a que la energa y el momentum estos muones sean, a su vez, correctamente caracterizados, incluyendo sus incertidumbres sistematicas. El objetivo de este trabajo de tesis es precisamente presentar la metodologa usada para medir las energas de los muones producidos por interacciones de neutrinos y sus correspondientes incertidumbres asociadas a dicha medicion.« less

Múltiples estados de desorden en el etanol sólido

NASA Astrophysics Data System (ADS)

Fernández-Perea, R.

El diagrama de fases del etanol por debajo de los 169 K será presentado. Se mostrará que el etanol puede solidificarse en tres fases con diversos niveles de desorden,(como un vidrio(G), como un vidrio orientacional (OG) y como un cristal de fase rotora (RP)) además de en una fase totalmente cristalina. Las estructuras de estas tres fases serán presentadas tal y como se deducen a partir de diversas medidas de difracción de neutrones al igual que las proporciones de los isómeros de dicho material en las fases desordenadas y se compararán con los resultados de la fase cristalina y del líquido superenfriado. Igualmente diversas medidas sobre su dinámica serán presentadas, tanto de dispersión de neutrones, como de capacidad calorífica y de medidas dieléctricas y comparadas con modelos teóricos y simulaciones para tratar de explicar los procesos de relajación observados y las transiciones entre las diversas fases.

Longitudinal hemodynamics in acute phase of treatment with labetalol in hypertensive pregnant women to predict need for vasodilatory therapy.

PubMed

Stott, D; Bolten, M; Paraschiv, D; Papastefanou, I; Chambers, J B; Kametas, N A

2017-01-01

Hypertensive pregnant women who do not respond to treatment with labetalol to control blood pressure (BP), but require vasodilatory therapy, progress rapidly to severe hypertension. This could be delayed by early recognition and individualized treatment. In this study, we sought to create prediction models from data at presentation and at 1 h and 24 h after commencement of treatment to identify patients who will not have a sustained response to labetalol and therefore need vasodilatory therapy. The study population comprised 134 women presenting with hypertension at a UK hospital. Treatment with oral labetalol was administered when BP was > 150/100 mmHg or > 140/90 mmHg with systemic disease. BP and hemodynamic parameters were recorded at presentation and at 1 h and 24 h after commencement of treatment. Labetalol doses were titrated to maintain BP around 135/85 mmHg. Women with unresponsive BP, despite labetalol dose maximization (2400 mg/day), received additional vasodilatory therapy with nifedipine. Binary logistic and longitudinal (mixed-model) data analyses were performed to create prediction models anticipating the likelihood of hypertensive women needing vasodilatory therapy. The prediction models were created from data at presentation and at 1 h and 24 h after treatment, to assess the value of central hemodynamics relative to the predictive power of BP, heart rate and demographic variables at these intervals. Twenty-two percent of our cohort required additional vasodilatory therapy antenatally. These women had higher rates of severe hypertension and delivered smaller babies at earlier gestational ages. The unresponsive women were more likely to be of black ethnicity, had higher BP and peripheral vascular resistance (PVR), and lower heart rate and cardiac output (CO) at presentation. Those who needed vasodilatory therapy showed an initial decrease in BP and PVR, which rebounded at 24 h, whereas BP and PVR in those who responded to labetalol showed a sustained decrease at 1 h and 24 h. Stroke volume and CO did not decrease during the acute phase of treatment in either group. The best model for prediction of the need for vasodilators was provided at 24 h by combining ethnicity and longitudinal BP and heart rate changes. The model achieved a detection rate of 100% for a false-positive rate of 20% and an area under the receiver-operating characteristics curve of 0.97. Maternal demographics and hemodynamic changes in the acute phase of labetalol monotherapy provide a powerful tool to identify hypertensive pregnant patients who are unlikely to have their BP controlled by this therapy and will consequently need additional vasodilatory therapy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Las embarazadas hipertensas que no responden al tratamiento con labetalol para el control de la presión arterial (PA), pero que requieren terapia vasodilatadora, evolucionan rápidamente hacia una hipertensión severa. Ésta se puede retrasar mediante un diagnóstico precoz y un tratamiento individual. En este estudio se ha tratado de crear modelos de predicción a partir de datos al inicio del tratamiento y al cabo de 1 hora y de 24 horas después del mismo, para identificar a las pacientes que no mostrarán una respuesta constante al labetalol y que por lo tanto necesitarán terapia vasodilatadora. MÉTODOS: La población de estudio incluyó 134 mujeres con hipertensión en un hospital del Reino Unido. El tratamiento con labetalol por vía oral se administró cuando la PA fue >150/100 mm de Hg o >140/90 mm de Hg con enfermedad multisistémica. Se registró la PA y los parámetros hemodinámicos tanto al inicio como al cabo de 1 h y de 24 h después del inicio del tratamiento. Las dosis de Labetalol se ajustaron para mantener la PA en torno a los 135/85 mm de Hg. Las mujeres cuya PA no produjo respuesta, a pesar de haberles administrado la dosis máxima de labetalol (2400 mg/día), recibieron terapia vasodilatadora adicional con nifedipino. Se realizaron análisis de datos mediante logística binaria y longitudinal (modelo mixto), para crear modelos de predicción con los que pronosticar la probabilidad de la necesidad de terapia vasodilatadora en mujeres hipertensas. Los modelos de predicción se crearon a partir de datos al inicio y al cabo de 1 hora y 24 horas del tratamiento, para evaluar el valor de los parámetros hemodinámicos principales con respecto a la capacidad predictiva de la PA, la frecuencia cardíaca y las variables demográficas en estos intervalos. El 22 % de la cohorte necesitó terapia vasodilatadora adicional antes del parto. Estas mujeres tuvieron tasas más altas de hipertensión grave y neonatos más pequeños en edades gestacionales más tempranas. Las mujeres que no respondieron al tratamiento fueron con más frecuencia de raza negra, tuvieron la PA y la resistencia vascular periférica (RVP) más alta, y la frecuencia cardíaca y el gasto cardíaco (GC) más bajos al inicio del tratamiento. Aquellas que necesitaron terapia vasodilatadora mostraron un descenso inicial de la PA y la RVP, que se recuperó al cabo de 24 h, mientras que la PA y la RVP en las que respondieron al labetalol mostraron una disminución constante al cabo de 1 h y de 24 h. El volumen sistólico y el GC no disminuyeron durante la fase aguda del tratamiento en ninguno de los grupos. El mejor modelo para la predicción de la necesidad de vasodilatadores se obtuvo a las 24 h mediante la combinación de la etnia con los cambios longitudinales de la PA y la frecuencia cardíaca. El modelo alcanzó una tasa de detección del 100% para una tasa de falsos positivos del 20% y un área bajo la curva de características operativas del receptor de 0,97. CONCLUSIÓN: Los datos demográficos maternos y los cambios hemodinámicos en la fase aguda de la monoterapia con labetalol constituyen una herramienta poderosa para identificar a las pacientes embarazadas hipertensas con pocas probabilidades de que se les pueda controlar su PA mediante esta terapia y que por lo tanto necesitarán terapia vasodilatadora adicional. : 、(blood pressure,BP),。。,1 h24 h,。 : 134。BP>150/100 mmHgBP>140/90 mmHg。1 h24 hBP。,BP135/85 mmHg。BP,()。logistic(),。1 h24 h,,BP、。 : 22%。。,BP(peripheral vascular resistance,PVR),(cardiac output,CO)。BPPVR,24 h,1 h24 hBPPVR。CO。24hBP。100%,20%,0.97。 : ,BP。. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Overview of deformable mirror technologies for adaptive optics and astronomy

NASA Astrophysics Data System (ADS)

Madec, P.-Y.

2012-07-01

From the ardent bucklers used during the Syracuse battle to set fire to Romans’ ships to more contemporary piezoelectric deformable mirrors widely used in astronomy, from very large voice coil deformable mirrors considered in future Extremely Large Telescopes to very small and compact ones embedded in Multi Object Adaptive Optics systems, this paper aims at giving an overview of Deformable Mirror technology for Adaptive Optics and Astronomy. First the main drivers for the design of Deformable Mirrors are recalled, not only related to atmospheric aberration compensation but also to environmental conditions or mechanical constraints. Then the different technologies available today for the manufacturing of Deformable Mirrors will be described, pros and cons analyzed. A review of the Companies and Institutes with capabilities in delivering Deformable Mirrors to astronomers will be presented, as well as lessons learned from the past 25 years of technological development and operation on sky. In conclusion, perspective will be tentatively drawn for what regards the future of Deformable Mirror technology for Astronomy.

Dinámica global en galaxias elípticas

NASA Astrophysics Data System (ADS)

Pérez, M. J.; Cincotta, P. M.; Giordano, C. M.

Con el propósito de determinar propiedades dinámicas globales en sistemas triaxiales no integrables, utilizamos una nueva herramienta conocida como ``Mean Exponential Growth factor of Nearby Orbits'' (MEGNO), introducida por Cincotta y Simó (2000). Esta técnica no sólo resulta eficiente para investigar ambas componentes del espacio fase, regular y caótica, sino que también, provee una medida de la hiperbolicidad en el dominio caótico que coincide con la dada por el Lyapunov Characteristic Number (LCN). Previamente este método ha sido aplicado al estudio de modelos simples, y últimamente en el campo de la Mecánica Celeste, al estudio de sistemas planetarios extrasolares. En esta presentación, ilustraremos algunas de las propiedades más importantes del MEGNO, aplic& acute;andolo al potencial tridimensional de Stäckel perturbado.

[In Process Citation].

PubMed

Gonçalves Schemitt, Elizângela; Raskopf Colares, Josieli; Minuzzo Hartmann, Renata; Morgan-Martins, María Isabel; Marroni, Cláudio Augusto; Tuñón, M Jesús; Possa Marroni, Norma

2016-03-25

Introducción: la insuficiencia hepática fulminante (IHF) es un síndrome clínico poco frecuente, que se caracteriza por una disfunción hepática severa y repentina. La tioacetamida (TAA) es una hepatotoxina cuya administración puede inducir necrosis centrolobulillar en las células hepáticas y aumentar la formación de especies reactivas de oxígeno y la peroxidación lipídica en ratas. La glutamina es un precursor para la síntesis de glutatión. Objetivo: el objetivo del estudio es evaluar los efectos antioxidantes de la glutamina en un modelo de rata de IHF inducida por TAA. Métodos: ratas macho Wistar se dividieron en cuatro grupos de acuerdo con el tratamiento y el tiempo de evaluación: control, glutamina (25 mg/kg), tioacetamida (400 mg/kg) y tioacetamida más glutamina. Los animales se evaluaron después de 24, 36 y 48 horas. Se recogieron muestras de sangre para el análisis de los niveles de aspartato aminotransferasa (AST), alanina aminotransferasa (ALT), fosfatasa alcalina (AP), bilirrubina total (TB) y creatinina (CRE), y muestras de hígado para evaluar la peroxidación lipídica, las sustancias reactivas al ácido tiobarbitúrico (TBARS), la actividad de las enzimas antioxidantes superóxido dismutasa (SOD), glutatión peroxidasa (GPx), catalasa (CAT) y glutatión S-transferasa (GST). Además se midieron mediante inmunohistoquímica el factor nuclear kappa N (NF-κB), el fator de necrosis tumoral (TNF-α) y la óxido nítrico sintasa inducible (iNOS). Resultados: la TAA causó alteraciones en los parámetros bioquímicos e histológicos, y el aumento de los marcadores del proceso inflamatorio. Los niveles de TBARS y la actividad de SOD y GST fueron significativamente inferiores en los grupos de glutamina en comparación con TAA. La actividad de CAT se incrementó en los animales tratados con glutamina en comparación con la TAA. La actividad GPx también fue menor a las 36 y 48 h en los animales tratados com glutamina. El daño tisular y la expresión de NF-κB, TNF-α e iNOS fueron significativamente inferiores en los animales tratados con glutamina. Conclusión: la glutamina ha demostrado tener efectos protectores contra el daño hepático en un modelo de IHF inducida por TAA en la rata.

Constraining performance assessment models with tracer test results: a comparison between two conceptual models

NASA Astrophysics Data System (ADS)

McKenna, Sean A.; Selroos, Jan-Olof

Tracer tests are conducted to ascertain solute transport parameters of a single rock feature over a 5-m transport pathway. Two different conceptualizations of double-porosity solute transport provide estimates of the tracer breakthrough curves. One of the conceptualizations (single-rate) employs a single effective diffusion coefficient in a matrix with infinite penetration depth. However, the tracer retention between different flow paths can vary as the ratio of flow-wetted surface to flow rate differs between the path lines. The other conceptualization (multirate) employs a continuous distribution of multiple diffusion rate coefficients in a matrix with variable, yet finite, capacity. Application of these two models with the parameters estimated on the tracer test breakthrough curves produces transport results that differ by orders of magnitude in peak concentration and time to peak concentration at the performance assessment (PA) time and length scales (100,000 years and 1,000 m). These differences are examined by calculating the time limits for the diffusive capacity to act as an infinite medium. These limits are compared across both conceptual models and also against characteristic times for diffusion at both the tracer test and PA scales. Additionally, the differences between the models are examined by re-estimating parameters for the multirate model from the traditional double-porosity model results at the PA scale. Results indicate that for each model the amount of the diffusive capacity that acts as an infinite medium over the specified time scale explains the differences between the model results and that tracer tests alone cannot provide reliable estimates of transport parameters for the PA scale. Results of Monte Carlo runs of the transport models with varying travel times and path lengths show consistent results between models and suggest that the variation in flow-wetted surface to flow rate along path lines is insignificant relative to variability in the amount of diffusive capacity that can be accessed along the transport pathway. Contraindre le bilan des performances des modèles avec les résultats de traçages: une comparaison entre deux modèles conceptuels. Des tests de traçage sont mis en oeuvre pour étudier les paramètres de transport de soluté d'une roche sur une longueur de 5 m. Deux différents modèles de transport de soluté dans un milieu à double porosité fournissent des estimation des courbes de restitution. L'une des conceptualisations (unique taux de restitution) emploie un seul coefficient effectif de diffusion dans une matrice possédant une pénétration infinie en profondeur. Par ailleurs, la rétention du traceur entre les différentes lignes d'écoulement peut varier comme le rapport des débits aux surfaces mouillées et comme le rapport de la différence de débits entres les lignes d'écoulement. L'autre conceptualisation (taux multiple) emploie une distribution continue de coefficients de diffusion dans une matrice à capacité variable et finit. L'application de ces deux modèles avec les pa! ramètres estimés grâce aux courbes de restitution produit des résultats de transport qui différent de plusieurs ordres de grandeur dans la magnitude du pic, le temps du pic de concentration, au bilan des performances (PA) et aux échelles de distance (100,000 ans et 1,000 m). Ces différences sont éxaminées par l'intermédiaire des temps limites pour que la capacité diffusive équivaille à un milieu infini. Ces limites sont comparées à travers les modèles conceptuels ainsi que les temps caractéristiques de diffusion à l'échelle du test de traçage et à l'échelle du PA. Par ailleurs, les différences entre les modèles sont éxaminées en réestimant les paramètres pour le modèle à taux multiple à partir des résultats du modèle à double porosité à l'échelle du PA. Les résultats indiquent que pour chaque modèle la valeur de la capacité diffusive dans un milieu infini sur une période de temps spécifiée explique les différences entre les modèles et le ! fait que le test de traçage seul ne permet pas de déterminer les paramètres de transport à l'échelle du PA. Les résultats des simulations Monte Carlo du modèle de transport avec des temps et des distances de transport variables montrent des résultats concordances entre les différents modèles et suggère que la variation que la variation entre surface mouillée et le rapport de la différence de débits entre les lignes d'écoulement est insignifiante, en regard de la variabilité du montant de la capacité diffusive qui peut être accessible le long de la ligne de transport. Delimitando la eficacia de modelos de evaluación con resultados de pruebas de trazadores: una comparación entre dos modelos conceptuales. Se llevaron a cabo pruebas de trazadores para evaluar los parámetros de transporte de solutos en un rasgo rocoso a lo largo de una trayectoria de transporte de 5 m. Dos diferentes conceptualizaciones del transporte de solutos de porosidad doble aportan estimados de las curvas de avance de trazadores. Una de las conceptualizaciones (ritmo único) utiliza un coeficiente de difusión efectiva único en una matriz con profundidad de penetración infinita. Sin embargo, la retención del trazador entre diferentes trayectorias de flujo puede variar debido a que la relación entre la superficie mojada de flujo y el ritmo de flujo difiere entre las líneas de trayectoria. La otra conceptualización (multi-ritmo) utiliza una distribución continua de coeficientes de ritmos de difusión múltiple en una matriz con capacidad variable pero finita. La aplicación de los dos modelos con los parámetros estimados en base a las curvas de avance de trazadores producen resultados de transporte que difieren en varios órdenes de magnitud, tanto en concentración pico como en el tiempo en que se alcanza la concentración pico, en las escalas de evaluación de eficacia (PA) de tiempo y longitud (100,000 años y 1,000 m). Estas diferencias se examinan mediante el cálculo de límites de tiempo en que se considera que la capacidad difusiva actúa como un medio infinito. Estos límites se comparan en ambos modelos conceptuales y contra los tiempos característicos para difusión en escalas de PA y de prueba de trazador. Adicionalmente, se examinan las diferencias entre los modelos calculando de nuevo los parámetros para el modelo multi-ritmo a partir del modelo tradicional de doble porosidad a escala PA. Los resultados indican que para cada modelo la cantidad de la capacidad difusiva que actúa como un medio infinito sobre la escala de tiempo especificada explica las diferencias entre los resultados del modelo y que las pruebas de trazadores por sí solas no aportan cálculos confiables de los parámetros de transporte para la escala PA. Los resultados provenientes de corridas Monte Carlo de los modelos de transporte con distintos tiempos de viaje y diferentes longitudes de trayectorias muestran resultados consistentes entre modelos y sugieren que la variación en la relación de superficie de flujo mojada a ritmo de flujo a lo largo de las líneas de trayectoria es insignificante en relación con la variabilidad en la cantidad de capacidad difusiva que puede alcanzarse a lo largo de la trayectoria de transporte.

Estimaciones de Prevalencia del VIH por Género y Grupo de Riesgo en Tijuana, México: 2006

PubMed Central

Iñiguez-Stevens, Esmeralda; Brouwer, Kimberly C.; Hogg, Robert S.; Patterson, Thomas L.; Lozada, Remedios; Magis-Rodriguez, Carlos; Elder, John P.; Viani, Rolando M.; Strathdee, Steffanie A.

2010-01-01

OBJETIVO Estimar la prevalencia del VIH en adultos de 15-49 años de edad en Tijuana, México - en la población general y en subgrupos de riesgo en el 2006. METODOS Se obtuvieron datos demográficos del censo Mexicano del 2005, y la prevalencia del VIH se obtuvo de la literatura. Se construyó un modelo de prevalencia del VIH para la población general y de acuerdo al género. El análisis de sensibilidad consistió en estimar errores estándar del promedio-ponderado de la prevalencia del VIH y tomar derivados parciales con respecto a cada parámetro. RESULTADOS La prevalencia del VIH es 0.54%(N = 4,347) (Rango: 0.22%–0.86%, (N = 1,750–6,944)). Esto sugiere que 0.85%(Rango: 0.39%–1.31%) de los hombres y 0.22%(Rango: 0.04%–0.40%) de las mujeres podrían ser VIH-positivos. Los hombres que tienen sexo con hombres (HSH), las trabajadoras sexuales usuarias de drogas inyectables (MTS-UDI), MTS-noUDI, mujeres UDI, y los hombres UDI contribuyeron las proporciones más elevadas de personas infectadas por el VIH. CONCLUSIONES El número de adultos VIH-positivos entre subgrupos de riesgo en la población de Tijuana es considerable, marcando la necesidad de enforcar las intervenciones de prevención en sus necesidades específicas. El presente modelo estima que hasta 1 en cada 116 adultos podrían ser VIH-positivos. PMID:19685824

Associations between frailty syndrome and sociodemographic characteristics in long-lived individuals of a community.

PubMed

Grden, Clóris Regina Blanski; Lenardt, Maria Helena; Sousa, Jacy Aurelia Vieira de; Kusomota, Luciana; Dellaroza, Mara Solange Gomes; Betiolli, Susanne Elero

2017-06-05

investigating the association between frailty syndrome and sociodemographic characteristics in long-lived individuals of a community. a cross-sectional study with a proportional stratified sample consisting of 243 long-lived individuals. A structured instrument, scales and tests that comprise evaluating frailty were applied for data collection. Univariate and multivariate analyzes were performed by logistic regression (p<0.05) by Statistica 10(r) software and Odds Ratio (95% Confidence Interval) were calculated for the predictive models. of the 243 long-lived individuals evaluated, 36 (14.8%) were frail, 55 (63.8%) were pre-frail and 52 (21.4%) were not frail. A predominance of females (n=161; 66.3%), widows/widowers (n=158; 65%), who lived with family members (n=144; 59.3%) and in a self-reported satisfactory financial situation (n=108; 44.5%) was observed. A significant association was found between the demographic variable of age (p=0.043) and frailty syndrome. The best predictor model for the syndrome included the variables: gender, age and household companion. the variable of age contributed most to the fragilization process of long-lived individuals residing in the community. It is essential that gerontological nursing care contemplates early detection of this syndrome, considering age as being indicative of care needs. investigar a associação entre a síndrome da fragilidade física e as características sociodemográficas de idosos longevos da comunidade. estudo transversal, com amostra estratificada proporcional constituída por 243 longevos. Para a coleta de dados aplicaram-se instrumento estruturado, escalas e testes que compõem a avaliação da fragilidade física. Realizaram-se análises univariada e multivariada por regressão logística (p<0,05) pelo software Statistica 10(r) e para os modelos preditores foram calculadas Odds Ratio (Intervalo de Confiança de 95%). dos 243 longevos avaliados, 36 (14,8%) eram frágeis, 155 (63,8%) pré-frágeis e 52 (21,4%) não frágeis. Houve predomínio do sexo feminino (n=161; 66,3%), viúvos (n=158; 65%), que residiam com familiares (n=144; 59,3%) e com situação financeira autorrelatada satisfatória (n=108; 44,5%). Identificou-se associação significativa entre a variável demográfica idade (p=0,043) e a síndrome da fragilidade física. O melhor modelo preditor da síndrome compreendeu as variáveis: sexo, idade e com quem mora. a variável idade foi a que mais contribuiu para o processo de fragilização dos longevos que residem na comunidade. É essencial que o cuidado de enfermagem gerontológico contemple o rastreamento precoce da síndrome e considere a idade como um indicativo de necessidades de cuidados. investigar la asociación entre el síndrome de la fragilidad física y las características sociodemográficas de ancianos con edad más avanzada de la comunidad. estudio transversal, con muestra estratificada proporcional constituida por 243 longevos. Para la recolección de datos se aplicó: instrumento estructurado, escalas y pruebas que componen la evaluación de la fragilidad física. Se realizaron análisis univariado y multivariado por regresión logística (p<0,05) con el programa Statistica 10(r) y para los modelos de predicción fueron calculados los Odds Ratio (Intervalo de Confianza de 95%). de los 243 longevos evaluados, 36 (14,8%) eran frágiles, 155 (63,8%) pre-frágiles y 52 (21,4%) no frágiles. Hubo predominio del sexo femenino (n=161; 66,3%), viudos (n=158; 65%), residían con familiares (n=144; 59,3%) y con situación financiera autorrelatada satisfactoria (n=108; 44,5%). Se identificó asociación significativa entre la variable demográfica edad (p=0,043) y el síndrome de la fragilidad física. El mejor modelo predictor del síndrome contuvo las variables: sexo, edad y con quien reside. la variable edad fue la que más contribuyó para el proceso de fragilización de los longevos que residen en la comunidad. Es esencial que el cuidado de enfermería gerontológico contemple el rastreo precoz del síndrome y considere la edad como un indicativo de necesidades de cuidados.

Memorias del segundo simposio internacional sobre políticas, planificación y economía de los programas de protección contra incendios forestales: una visión global; 2004 Abril 19–22; Córdoba, España

Treesearch

Armando González-Cabán

2008-01-01

Estas memorias resumen el resultado de un simposio diseñado para discutir los problemas actuales que confrontan las agencias con responsabilidad para la protección contra incendios forestales a nivel federal y estadual en los EE.UU., al igual que agencias en la comunidad internacional. Los temas discutidos en el simposio incluyen economía del fuego, teoría y modelos...

Las líneas de aluminio neutro como diagnóstico cromosférico

NASA Astrophysics Data System (ADS)

Fernández Borda, R.; Mauas, P. J. D.

Se presenta un modelo atómico para el cálculo de las lí neas del Aluminio neutro que se forman en la cromósfera solar. En particular, se estudia la línea λ 3961 Å, que, por estar muy próxima a la lí nea H del Ca II y a Hɛ es muy frecuentemente observada. Observaciones en esta lí nea obtenidas con el espectrógrafo a instalarse en el CASLEO, serán utilizadas para el estudio de fulguraciones solares.

[Not Available].

PubMed

Arellano Ortiz, Ana Lidia; Jiménez Vega, Florinda; Díaz Hernández, Cecilia; Salcedo Vargas, Muricio; De la Mora Covarrubias, Antonio; López Díaz, José Alberto; Vargas Requena, Claudia Lucía; Cassís Nosthas, María Lorena

2016-07-19

Introducción: las lesiones intraepiteliales escamosas (LIE) son un estado de transición hacia el cáncer cervicouterino (CaCu) y un déficit de micronutrientes puede acelerar este proceso. Por ello, determinar la existencia de este déficit y conocer qué factores se asocian permitiría una posible prevención en esta población de riesgo.Objetivo: determinar la presencia de alguna deficiencia de micronutrientes involucrados en el proceso anticancerígeno y asociar este déficit con hábitos y factores demográficos en pacientes con LIE de Ciudad Juárez, Chihuahua, México.Métodos:en un estudio transversal analítico fueron seleccionadas 102 pacientes con LIE. Se realizó una encuesta dietaría (recordatorio de 24 horas) para estimar la ingesta de micronutrientes. La deficiencia fue determinada con un consumo < 75% de la ingesta diaria recomendada o sugerida (IDR o IDS) en México. Algunos hábitos y factores demográficos fueron obtenidos mediante la entrevista con la paciente. Se realizó un modelo de regresión logística para asociar la presencia de deficiencia con factores que afectan a la ingesta o incrementan el requerimiento de micronutrientes.Resultados:el retinol, ácido fólico, zinc, vitaminas C y E, considerados como micronutrientes en el proceso anticancerígeno del CaCu, se encontraron por debajo del 75% de la IDR. Aquellas mujeres con sobrepeso, obesidad y amas de casa se asociaron significativamente con la deficiencia de micronutrientes.Conclusión: el sobrepeso, la obesidad y la ocupación han sido asociados para presentar deficiencias de micronutrientes en este estudio. Estas variables convergen en una posible inseguridad alimentaria, la cual podría asociarse al incremento de incidencia de CaCu en México.

La Enseñanza/Aprendizaje del Modelo Sol-Tierra Análisis de la Situación Actual y Propuesta de Mejora Para la Formación de los Futuros Profesores de Primaria

NASA Astrophysics Data System (ADS)

Martínez Sebastià, Bernat

2004-12-01

This work is an extened summary of the autor's PhD thesis. It deals with the teaching of astronomy (day/night, seasons) in primary school. At first, students teachers' undestanding of astronomical concepts related to Sun-Earth system have been analysed. Taking into account the results of the previous analysis and using a socio-constructivist approach a teaching sequence has been designed. This sequence has been tested with different groups of students teachers showing an improvement in their undestanding of elementary astronomical concepts. El trabajo que presentamos es un resumen extenso de la tesis doctoral del autor. El enfoque utilizado ha sido tratar de ligar la investigación sobre las ideas, razonamientos y obstáculos de los profesores de primaria con la planificación de la enseñanza del modelo Sol-Tierra que permite explicar el ciclo día/noche y las estaciones. En primer lugar, se ha procedido a realizar un análisis crítico de los resultados que se obtienen en el aprendizaje de los contenidos astronómicos en la enseñanza habitual. En segundo lugar se ha diseñado un curriculum potencialmente superador de esta situación desde una orientación que concibe la enseñanza y el aprendizaje como un proceso de construcción de conocimientos en una estructura problematizada. Finalmente, esta secuencia didáctica ha sido experimentada con diferentes grupos de estudiantes de magisterio, mostrando una mejora relevante en la comprensión de los conceptos astronómicos fundamentales.

INTERVENCIÓN EDUCATIVA EFECTIVA EN VIH PARA MUJERES

PubMed Central

Miner, Sarah; Poupin, Lauren; Bernales, Margarita; Ferrer, Lilian; Cianelli, Rosina

2016-01-01

RESUMEN En Chile se estima que aproximadamente 38 mil personas viven con el Virus de Inmunodeficiencia Humana [VIH]. En el año 2001, 1.092 mujeres chilenas vivían con VIH, actualmente se cree que hay más de 7.600 mujeres con el virus. Frente a estas cifras surge la necesidad de crear estrategias de prevención dirigidas a mujeres chilenas. Objetivo analizar los estudios ya realizados en la prevención de VIH para determinar qué aspectos se deben incluir en programas exitosos de prevención de VIH en mujeres. Diseño y Método se realizó una revisión de la literatura utilizando la base de datos Proquest, CINAHL, Pubmed y Scielo. Los límites comprendieron: textos completos, de los últimos 10 años, de acceso gratuito y escrito en español o inglés. Se seleccionaron 15 artículos para la revisión. Resultados todos los artículos comprenden la evaluación del efecto de una intervención sobre conocimiento y conductas relacionadas con VIH/SIDA. Catorce muestran resultados significativos en cambios positivos de conducta o conocimientos relacionados con la prevención de VIH. Conclusiones los programas de prevención de VIH en mujeres pueden ser efectivos para lograr cambios de conducta y de conocimiento. Las intervenciones exitosas son aquellas basadas en teorías o modelos de prevención y en cambios de conductas, todas adaptadas a la cultura de la población estudiada. PMID:27667897

La mortalidad en adolescentes con cáncer: características clinicoepidemiológicas de muerte y aspectos éticos emergentes.

PubMed

Cicero-Oneto, Carlo Egysto; Mata-Valderrama, Guadalupe; Valdez-Martínez, Edith

Describir los aspectos epidemiológicos, clínicos y éticos de la mortalidad de los adolescentes con cáncer en -México. Se revisaron 63 expedientes clínicos de adolescentes (de 14 a 18 años de edad) con cáncer, fallecidos entre 2011 y 2014, para obtener información clínica y epidemiológica de su muerte. Los sitios de estudio fueron tres hospitales de concentración en la Ciudad de México. De los 40 adolescentes con criterios de fase terminal, 16 (40%) continuaron recibiendo tratamiento con fines curativos. De los 51 cuyo lugar de muerte era conocido, 45 (88%) murieron en hospital. De los 41 que murieron dentro de los 30 días de su última hospitalización, las muertes fueron principalmente debidas a complicaciones (51%), a progresión de la enfermedad (41%) o bien fueron muertes en tratamiento paliativo (7%, 3/41). La práctica oncológica descansa en lo que es conocido como modelo biomédico. Los resultados del estudio sugieren y apoyan la urgente necesidad de implementar verdaderos servicios de cuidados paliativos, pero más importante que eso, está el ímpetu de poner la ética de la práctica clínica en acción, y de ese modo reforzar la buena práctica de la medicina. Copyright: © 2018 SecretarÍa de Salud

Deformation sequences of the Day Nui Con Voi metamorphic belt, northern Vietnam

NASA Astrophysics Data System (ADS)

Yeh, M. W.; Lee, T. Y.; Lo, C. H.; Chung, S. L.; Lan, C. Y.; Lee, J. C.; Lin, T. S.; Lin, Y. J.

2003-04-01

The correlation of structure, microstructure and metamorphic assemblages is of fundamental importance to the understanding of the complex tectonic history and kinematics of the Day Nui Con Voi (DNCV) metamorphic belt in Vietnam along the Ailao Shan-Red River (ASRR) shear zone as it provides constraints on the relative timing of the deformation, kinematics and metamorphism. High-grade metamorphic rocks of amphibolite faces showed consistent deformation sequences of three folding events followed by one brittle deformation through all four cross sections from Lao Cai to Viet Tri indicated the DNCV belt experienced similar deformation condition throughout its length. The first deformation event, D1, produced up-right folds (locally preserved) with sub-vertical, NE-SW striking axial planes with dextral sense of shear probably formed during the early phase of the lowermost Triassic Indosinian orogeny. Followed by this compressional event is a gravitational collapsing event, D2, which is the major deformation and metamorphic event characterized by kyanite grade metamorphism and large scale horizontal folds with NW-SE (320) striking sub-horizontal axial pane showing sinsistral sense of shear most likely formed during the Oligocene-Miocene SE extrusion of Indochina peninsula. The 3rd folding event, D3, is a post-metamorphism doming event with NW-SE (310) striking sub-vertical axial plane that folded/tilted the once sub-horizontal D2 axial planes into shallowly (<30 degrees) NE dipping on the NE limb, and SW dipping on the SW limb possibly due to left-lateral movement of the N-S trending Xian Shui He fault system in Mid-Miocene. The outward decreasing of the metamorphic grade from kyanite to garnet then biotite indicated the D3 occurred post metamorphism. Reactivation of the sub-horizontal D2 fold axial planes showed dextral sense of shear possibly due to Late Miocene-Pliocene right-lateral movement of the ASRR shear zone. This right lateral movement continuously deformed the DNCV with brittle fractures such as joints and normal faults (D4) striking NE-SW to E-W and NW-SE.

Estudio teórico de la distribución catiónica en la capa octaédrica de silicatos laminares

NASA Astrophysics Data System (ADS)

Hernández-Laguna, A.

Los silicatos laminares son unos minerales de gran extensión en la corteza de nuestro y otros planetas, y se ha detectado su presencia en masas de partículas de polvo interplanatario. Están formados por láminas estructuradas en una capa tetraedros de sílice y una de octaédros de oxihidroxido de aluminio. Según el número de capas y la disposición aparecen distintos minerales. Además, también pueden aparecer distintos minerales como consecuencia de la substitución isomórfica de cationes en la capas, en particular, Al(III) por Si en la capa tetraédrica y Fe(III) y/o Mg(II) por Al(III) en la octaédrica. Cuando el catión substituyente presenta un estado de oxidación más bajo que al que substituye genera carga negativa que tiene que neutralizarse con cationes que se disponen en el espacio interlaminar. En este trabajo vamos a estudiar, mediante distintos métodos computacionales, las distribuciones de dichos cationes de substitución en la capa octaédrica de silicatos laminares 2:1 (dos capas tetraédricas y en medio una octaédrica), en particular, en los minerales esmectitas e ilitas. En primer lugar, estudiaremos la distribución de dichos cationes en la capa octaédrica en un modelo de gas reticular por el método de Monte Carlo, minimizando el número de pares de cationes Al, Fe y Mg de nuestro modelo con respecto a los procedentes de resultados espectroscópicos de muestras de minerales. Posteriormente, y mediante un modelo de potenciales empíricos, estudiamos la energética de las distribuciones binarias en dichos minerales, generando unos potenciales de interacción intercambio a dos y tres cationes (extrapolables a cualquier filosilicato) que son la base para una investigación Monte Carlo-"simulated-annealing" en la que se encuentran las transiciones de fase y las estructuras ordenadas, dependiendo dichas estructuras y la temperatura de cambio de fase de la de la naturaleza y concentración de los cationes de substitución. También se han investigado dichas distribuciones mediante métodos mecano-cuánticos DFT.

Reduced Order Modeling for Rapid Simulation of Blast Events of a Military Ground Vehicle and Its Occupants

DTIC Science & Technology

2014-08-12

deformation of the hull due to blast . An LS- Dyna model which included the ConWep function [6] was run, with a charge mass corresponding to a STANAG...different models and blast loadings are shown in Table 3. These responses are based on generic seat properties and assumed dummy position, which can be...Comparison between MADYMO and LS- Dyna models An LS- Dyna model with ConWep blast force applied to all segments of the hull floor and a MADYMO model with

Modelling of deformation process for the layer of elastoviscoplastic media under surface action of periodic force of arbitrary type

NASA Astrophysics Data System (ADS)

Mikheyev, V. V.; Saveliev, S. V.

2018-01-01

Description of deflected mode for different types of materials under action of external force plays special role for wide variety of applications - from construction mechanics to circuits engineering. This article con-siders the problem of plastic deformation of the layer of elastoviscolastic soil under surface periodic force. The problem was solved with use of the modified lumped parameters approach which takes into account close to real distribution of normal stress in the depth of the layer along with changes in local mechanical properties of the material taking place during plastic deformation. Special numeric algorithm was worked out for computer modeling of the process. As an example of application suggested algorithm was realized for the deformation of the layer of elasoviscoplastic material by the source of external lateral force with the parameters of real technological process of soil compaction.

Fotogrammetria dell'Obelisco Vaticano con il Sole

NASA Astrophysics Data System (ADS)

Sigismondi, Costantino

2016-05-01

The Vatican Obelisk has been moved to St Peter's square by Domenico Fontana in 1586. The measurement of its height using the shadow on the floor is compared with Fontana's original data and with digital photo, corrected by perspective. A pincushion deformation is found in the camera.

[In Process Citation].

PubMed

Guzmán-Mercado, Elizabeth; Vásquez-Garibay, Edgar M; Troyo-Sanroman, Rogelio; Romero-Velarde, Enrique

2016-03-25

Objetivo: identificar los hábitos alimentarios de adolescentes embarazadas en cuatro estados civiles diferentes: casada, cohabita con una pareja, soltera sin pareja y soltera con una pareja. Métodos: en estudio transversal, se incluyeron 321 adolescentes embarazadas de 13-19 años que acudieron al Hospital Civil de Guadalajara Dr. Juan I Menchaca, Guadalajara (Jalisco, México). Se encontraban sanas, en cualquier trimestre del embarazo y pertenecían a un nivel socioe-conómico bajo o medio-bajo. El estado civil se estratificó en: casadas; en unión libre; soltera con una pareja y soltera sin pareja. Se incluyeron datos socio-demográficos, económicos y de hábitos de alimentación. Se utilizaron pruebas de ANOVA, pruebas post-hoc para Chi 2 , razón de momios y modelos de regresión logística. Resultados: la frecuencia de las adolescentes casadas fue de 9,3%, 59,8% en unión libre, 15,3% eran solteras sin pareja y 15,6% solteras con pareja. La baja escolaridad (RM 2,6 [1,5-4,4]) y la ocupación en el hogar (RM 4,47 [1,99-10,0]) predominaron entre las adolescentes en unión libre; la ocupación en el hogar (RM 0,28 [0,127-0,61]) y cenar sin compañía (RM 4,12 [1,62-10,8]) fueron significativamente más frecuentes en adolescentes sin pareja. El consumo de verduras fue menor en las adolescentes casadas y en quienes cohabitaban con pareja; el consumo de frijoles y pan dulce fue menor en adolescentes embarazadas casadas. Conclusión: debido a que ciertas variables y hábitos de alimentación mostraron diferencias entre los grupos es pertinente analizar las adolescentes embarazadas de acuerdo a su estado civil.

Distribución del continuo ultravioleta e infrarrojo en estrellas Be

NASA Astrophysics Data System (ADS)

Cruzado, A.; Ringuelet, A.; di Rocco, H.

Estamos interesados en interpretar los excesos de flujo infrarrojo y/o ultravioleta observados en estrellas Be con respecto al de estrellas B normales, así como su posible correlación. Una envoltura rodeando la estrella distingue una estrella Be de una B normal; para explicar las observaciones es necesario entonces tener en cuenta todos los posibles procesos físicos que en ella tienen lugar. Adoptando un modelo atmosférico específico, hemos estudiado el proceso de recombinación dielectrónica de metales como MgII y FeII, teniendo en cuenta la posible influencia de la opacidad del medio en el flujo emitido.

Comportamiento dinámico de asteroides en la resonancia 2:1

NASA Astrophysics Data System (ADS)

López García, F.; Brunini, A.

El propósito de este trabajo es mostrar los resultados obtenidos del estudio del movimiento de asteroides cercanos a la conmensurabilidad 2:1 con el movimiento medio de Júpiter, analizando el comportamiento de órbitas de asteroides reales y ficticios. Se analizan los tiempos de Lyapunov obtenidos a partir de la integración de las ecuaciones del movimiento. Se han estudiado la órbitas utilizando el modelo de cinco cuerpos y se han considerado los casos planar y espacial. Las simulaciones numéricas se realizaron utilizando integradores simpléticos y el intervalo de tiempo de integración fue de T = 107 años.

Revision curricular a partir de un analisis comparativo de las discrepancias en los curriculos de una escuela de optometria en Puerto Rico con las competencias requeridas para las agencias de revalida y acreditacion 2004

NASA Astrophysics Data System (ADS)

Rivera Pacheco, Andres

El proposito de esta investigacion, un estudio cualitativo de caso, fue comparar y contrastar el curriculo vigente de la Escuela de Optometria de la UIAPR con las competencias y estandares requeridos por las agencias de acreditacion y de revalida. Con este proposito, decidimos realizar una revision y un analisis de documentos: el prontuario de cada uno de los cursos de los curriculos implantados en el 1993 y en el 2001; las competencias y estandares establecidos por las agencias de revalida y de acreditacion; y las estadisticas en las que se analiza el porcentaje de estudiantes que aprueban cada una de las partes de los examenes de revalida entre el 1998 al 2003. Se realizaron entrevistas dirigidas para dar apoyo y complementar la revision y el analisis de estos documentos. Los participantes de las entrevistas fueron tres estudiantes de la clase de optometria del 2004 (ultima clase del curriculo del 1993); tres estudiantes de la clase de optometria del 2005 (primera clase graduanda del curriculo vigente) y tres profesores y/o directores de los Departamentos de Ciencias Basicas, Ciencias Clinicas y Cuidado al Paciente. Esta investigacion se enmarco en el modelo de evaluacion curricular de discrepancia de Malcolm Provus y en el modelo de desarrollo basado en competencias. Uno de los hallazgos mas importantes del estudio es que los cambios que se implantaron al curriculo del 2001 no han logrado que los estudiantes mejoren su ejecucion en los examenes de revalida. Por otro lado, se encontro que el curriculo vigente atiende completamente los estandares de la practica de Optometria, pero no las competencias. Esta informacion fue validada mediante el uso de una tabla de cotejo para el analisis de los cursos y de la informacion obtenida de las entrevistas. El estudio determina y concluye que existen discrepancias entre los prontuarios de los cursos del curriculo y las competencias requeridas por la agencia de revalida. Segundo, que el Departamento de Ciencias Basicas es el que presenta mas deficiencias en el desarrollo de las competencias. El investigador recomienda disenar e implantar un curriculo basado en competencias y proveer formacion en didactica y procesos de aprendizaje a los profesores.

Desarrollo curricular, conciencia ambiental y tecnologia para estudiantes de intermedia: Una investigacion en accion

NASA Astrophysics Data System (ADS)

Rodriguez Ramos, Teresita

Se llevó a cabo una investigación en acción con los propósitos de 1) documentar las relaciones de las tecnologías de la información y la comunicación en las clases de ciencias de escuela intermedia como elemento de apoyo cuando se aborda el tema ambiental y sus conceptos pertinentes, a partir de las observaciones de la investigadora, así como las entrevistas y diarios reflexivos de los estudiantes de una escuela intermedia en la zona metropolitana, y luego 2) diseñar una unidad instruccional sobre el tema ambiental que integre actividades tecnologías para el curso de ciencias de la escuela intermedia según el modelo PROCIC y las observaciones que hayan iniciado los estudiantes participantes. Finalmente, se plantearon las implicaciones educativas para el currículo del Programa de Ciencias al instrumentar este modelo de unidad mediante PROCIC, e integrado la tecnología y el tema ambiental. Los hallazgos se analizaron y se categorizaron de acuerdo con las preguntas de investigación. El hallazgo principal de la investigación aborda las cuatro relaciones centrales en las que se articula la utilización de las tecnologías y sus aplicaciones en la clase de ciencias. Estas cuatro relaciones que recogen la posición de los estudiantes son: 1) Perspectiva de los estudiantes hacia la tecnología. 2) Participación de los estudiantes en los aspectos docentes. 3) Aprendizaje estudiantil sobre el ambiente, y 4) Conciencia ambiental en relación con la vida diaria. Estas relaciones ponen de manifiesto,cómo se plantea en las implicaciones, la necesidad de más investigación en acción en la sala de clases, la importancia—como tema transversal—de la conciencia ambiental mediante la tecnología al construir conocimientos significativos dentro y fuera de la escuela, asó como, valorar la investigación y la dialogicidad en la sala de clases como actividades que obligan al reexamen de la práctica didáctica en su formas curriculares de objetivos, recursos, actividades, evaluación, entre otros. Estos planteamientos definen la unidad curricular que se propone en el cuatro capítulo.

A predictive formula of the contraction stress in restorative and luting materials attending to free and adhered surfaces, volume and deformation.

PubMed

Miguel, A; de la Macorra, J C

2001-05-01

To find a predictive formula of stress, considering the surfaces (free, adhered) involved, the volume and characteristics of material and the deformation of the measuring system. 231 samples of five chemically cured restoratives (Silar (SIL, 23), Clearfil F2 (CLE, 39), P10 (P10, 33), Concise (CON, 30), Isopast (ISO, 28)) and four luting (3M Experimental 241 (EXM, 20), Variolink II (VAR, 13), Vitremer LC (VTM, 20) and Dyract Cem (DYR, 25)) materials were allowed to polymerize until they reached a maximum tension (T(max), 25 min) between six pairs (null 5.81, 8.5, 11.26, 12.42, 17.02, 23.14 mm) of polished metallic discs (range of distances: 0.02-5.9 mm) mounted in a tension machine. The deformation of the measuring system was measured for the recorded forces. A descriptive non-linear formula T(max)=KVol(-3.267)FS(3.283)AS(0.642)Def(0.561) was found that individualizes the material's characteristics (K) that considers volume (Vol), free (FS) and adhered (AS) surfaces and deformation (Def) of the system for each force. This formula renders good correlation (material K (r(2) coefficient)): SIL 0.9998 (0.995), CLE 1.0062 (0.989), P10 1.0224 (0.990), CON 0.9908 (0.992), ISO 0.9648 (0.974), EXM 1.0083 (0.991), VAR 0.9777 (0.996), VTM 0.9925 (0.993), DYR 0.9971 (0.997) between actual T(max) and calculated Tension. There are statistically significant differences (p=0.002) between K values of both (restorative and luting) groups. Predictive parameters have influence in a different way to what is actually considered, if the system is allowed to have deformation, as occurs naturally and volume and material's characteristics are considered.

Detachment of affinity-captured bioparticles by elastic deformation of a macroporous hydrogel

PubMed Central

Dainiak, Maria B.; Kumar, Ashok; Galaev, Igor Yu.; Mattiasson, Bo

2006-01-01

Adsorption of bioparticles to affinity surfaces involves polyvalent interactions, complicating greatly the recovery of the adsorbed material. A unique system for the efficient binding and release of different cells and particles is described. Affinity-bound bioparticles and synthetic particles are detached from the macroporous hydrogel matrix, a so-called cryogel, when the cryogel undergoes elastic deformation. The particle detachment upon elastic deformation is believed to be due to breaking of many of the multipoint attachments between the particles and the affinity matrix and the change in the distance between affinity ligands when the matrix is deformed. However, no release of affinity-bound protein occurred upon elastic deformation. The phenomenon of particle detachment upon elastic deformation is believed to be of a generic nature, because it was demonstrated for a variety of bioparticles of different sizes and for synthetic particles, for different ligand–receptor pairs (IgG–protein A, sugar–ConA, metal ion–chelating ligand), and when the deformation was caused by either external forces (mechanical deformation) or internal forces (the shrinkage of thermosensitive, macroporous hydrogel upon an increase in temperature). The elasticity of cryogel monoliths ensures high recovery of captured cells under mild conditions, with highly retained viability. This property, along with their continuous porous structure makes cryogel monoliths very attractive for applications in affinity cell separation. PMID:16418282

Serial hemodynamic monitoring to guide treatment of maternal hypertension leads to reduction in severe hypertension.

PubMed

Stott, D; Papastefanou, I; Paraschiv, D; Clark, K; Kametas, N A

2017-01-01

To examine whether treatment for hypertension in pregnancy that is guided by serial monitoring of maternal central hemodynamics leads to a reduction in the rate of severe hypertension, defined as blood pressure ≥ 160/110 mmHg; and to assess the distinct longitudinal hemodynamic profiles associated with beta-blocker monotherapy, vasodilator monotherapy and dual agent therapy, and their relationships with outcomes, including fetal growth restriction. This was a prospective observational study at a dedicated antenatal hypertension clinic in a tertiary UK hospital. Fifty-two untreated women presenting with hypertension were recruited consecutively and started on treatment, either with a beta-blocker or a vasodilator. The choice of initial antihypertensive agent was determined according to a model constructed previously to predict the response to the beta-blocker labetalol in pregnant women needing antihypertensive treatment. At presentation, the demographic and maternal hemodynamic variables associated with a therapeutic response to labetalol, defined as blood pressure control < 140/90 mmHg with labetalol monotherapy throughout pregnancy, were ascertained and analyzed with logistic regression to create a model to predict sustained blood pressure control as described above. The women were reviewed regularly until delivery and underwent serial hemodynamic monitoring throughout pregnancy. If their blood pressure was elevated, the prediction model was referred to again to determine if alternative antihypertensive therapy, either with additional beta-blocker or a vasodilator, should be added. Treatment by referring to results of serial hemodynamic monitoring reduced the rate of severe antenatal hypertension from 18% to 3.8%. Seventy-seven percent of women were initially prescribed a beta-blocker and 23% a vasodilator. The group that maintained good blood pressure control with beta-blocker monotherapy had the best fetal and maternal outcomes. They had lower blood pressures at presentation and throughout gestation, demonstrated well-maintained cardiac output and had the lowest rates of fetal growth restriction. The groups that required dual therapy to control their blood pressure had persistently higher blood pressure and rate of fetal growth restriction. The groups that required vasodilator therapy due to high levels of peripheral vascular resistance, either at presentation or later in pregnancy, accounted for 81% of cases with fetal growth restriction. Using serial hemodynamic monitoring in pregnancy to guide treatment of hypertension significantly reduces the rate of severe hypertension and allows identification of high-resistance, low-output hypertensive pregnancies that are associated with an increased rate of fetal growth restriction. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Examinar si el tratamiento para la hipertensión en el embarazo guiado por un seguimiento en serie de las principales constantes hemodinámicas de la madre conduce a una reducción en la tasa de hipertensión grave, definida como presión arterial ≥ 160/110 mmHg; y evaluar los diferentes perfiles hemodinámicos longitudinales asociados a la monoterapia con beta-bloqueantes, la monoterapia con vasodilatadores y la terapia dual, y su relación con los resultados, como la restricción del crecimiento fetal. MÉTODOS: Se realizó un estudio observacional prospectivo en una clínica especializada en hipertensión prenatal de un hospital de atención terciaria del Reino Unido. Se reclutaron consecutivamente a cincuenta y dos mujeres no tratadas que presentaban hipertensión y se comenzó a tratarlas, bien con un beta-bloqueante o bien con un vasodilatador. La elección del agente antihipertensivo inicial se determinó de acuerdo con un modelo elaborado previamente para predecir la respuesta al beta-bloqueante labetalol en mujeres embarazadas que necesitaban tratamiento antihipertensivo. Al inicio se registraron las características demográficas y las variables hemodinámicas maternas asociadas con una respuesta terapéutica al labetalol, definida como un control de la presión arterial < 140/90 mmHg con monoterapia de labetalol durante todo el embarazo que se analizó mediante regresión logística para crear un modelo con el que pronosticar un control sostenido de la presión arterial, como se describe arriba. Las mujeres fueron sometidas a revisiones regulares hasta el momento del parto y se les hizo un seguimiento hemodinámico en serie durante todo el embarazo. Si la presión arterial era elevada, se empleó de nuevo el modelo de predicción para determinar si se debería añadir un tratamiento antihipertensivo alternativo, ya sea con un beta-bloqueante adicional o con un vasodilatador. El tratamiento que tuvo en cuenta los resultados del seguimiento hemodinámico en serie redujo la tasa de hipertensión prenatal grave del 18% al 3,8%. Al 77% de las mujeres se les recetó inicialmente un y al 23% un vasodilatador. El grupo que mantuvo un buen control de la presión arterial con monoterapia de beta-bloqueantes logró mejores resultados fetales y maternos. Este grupo tuvo menor presión arterial al inicio y durante toda la gestación, mostró un gasto cardíaco en buen estado y tuvo las tasas más bajas de restricción del crecimiento fetal. Los grupos que requirieron terapia dual para controlar su presión arterial mostraron persistentemente una mayor presión arterial y un mayor ritmo de restricción del crecimiento fetal. Los grupos que requirieron tratamiento vasodilatador debido a los altos niveles de resistencia vascular periférica, tanto al inicio como durante el embarazo, representaron el 81% de los casos con restricción del crecimiento fetal. CONCLUSIÓN: El uso de un seguimiento hemodinámico en serie en el embarazo como guía para el tratamiento de la hipertensión reduce significativamente la tasa de hipertensión severa y permite la identificación de embarazos con hipertensión de alta resistencia y malos resultados, asociados con una mayor tasa de restricción del crecimiento fetal. : (≥ 160/110 mmHg);β、,()。 : 。52、,β。β。,(<140/90 mmHg),logistic,。,。,(β)。 : ,18%3.8%。77%β,23%。β。,,。,。,81%。 : ,,、。. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

High-pressure thermal aureoles around two Neoproterozoic synorogenic magmatic epidote-bearing granitoids, Northeastern Brazil

NASA Astrophysics Data System (ADS)

Caby, Renaud; Sial, Alcides N.; Ferreira, Valderez P.

2009-02-01

Unusual high-pressure inner thermal aureoles are described from the Minador and Angico Torto epidote-bearing tonalitic plutons that emplaced into greenschist-facies metasedimentary rocks of the Neoproterozoic Cachoeirinha-Salgueiro belt, northeastern Brazil. The foliated pelitic hornfelses display the mineral assemblage garnet, kyanite, staurolite, muscovite, biotite, plagioclase ± quartz. Rare fibrolite is only found very close to the contacts. Hornfelses display steep mineral lineations and steeply-dipping foliations concordant with magmatic contacts. Leucocratic veinlets containing quartz, oligoclase, garnet, kyanite, staurolite, rutile and ilmenite suggest that limited melting conditions were reached very close to magmatic contacts ( T ⩾ 650 °C, P around 8 kbar). These high-pressure hornfelses form a few meters thick, rigid envelopes around the two plutons. Contrary to known examples of kyanite-bearing hornfelses that recorded high-temperature decompression, the nearly isobaric cooling down to ca. 450 °C is constrained by 3.20-3.30 Si contents of retrogressive phengites from both inner hornfelses and ductilely-deformed tonalite at the pluton margins. Isograds and bathograds are, therefore, apparently telescoped due to HP/LT shearing, possibly caused by subsequent differential vertical movements affecting these two solidified plutons. The unusual depth of emplacement of these syn-kinematic calc-alkaline plutons is explained by a tentative geodynamic model involving a pre-620 Ma-subduction setting. Resumen Las aureolas internas que rodean dos plutones tonalíticos emplazados dentro de rocas cajas en facies esquistos verdes del Cinturón-plegado Cachoeirinha-Salgueiro al noreste de Brasil, contienen hornfelses pelíticos foliados con granate, kyanita, estaurolita, muscovita, biotita, plagioclasa ± cuarzo. Fibrolita es rara ó es encontrada solamente cerca de las zonas de contacto. Los hornfelses desarrollaron foliaciones concordantes con buzamiento fuerte cerca de los contactos magmáticos y muestran lineaciones minerales casi verticales. Venillas leucocraticas contienen cuarzo, oligoclasa, granate, kyanita, estaurolita, rutilo e ilmenita sugiriendo que el límite en las condiciones de fusión fueron cercanas a los contactos magmáticos ( T ⩾ 650 °C, P entorno 8 kbar). Estos hornfelses de alta presión forman una cobertura rígida de poco metros entorno a los dos plutones. Contrariamente a lo conocido en diferentes ejemplos de hornfelses con kyanita con registro de descompresión, la isóbara de enfriamiento para cerca de 450 °C está controlada por el contenido de Si 3.20-3.30 de fengitas retrógradas, en los hornfelses internos y en las márgenes de los plutones donde las tonalitas están deformadas ductilmente. Isógradas y batógradas son, por lo tanto, aparentemente telescopadas debido a cizalla de alta presión/baja temperatura, posiblemente causado por subsecuentes movimientos verticales diferenciales afectando estos dos plutones solidificados. El emplazamiento a una profundidad inusual de estos plutones calci-alcalinos syn-cinemáticos es explicado por un modelo geodinámico tentativo que involucra un escenario de subducción pre-620 Ma.

Hydrochemical tracers in the middle Rio Grande Basin, USA: 2. Calibration of a groundwater-flow model

NASA Astrophysics Data System (ADS)

Sanford, Ward E.; Plummer, L. Niel; McAda, Douglas P.; Bexfield, Laura M.; Anderholm, Scott K.

The calibration of a groundwater model with the aid of hydrochemical data has demonstrated that low recharge rates in the Middle Rio Grande Basin may be responsible for a groundwater trough in the center of the basin and for a substantial amount of Rio Grande water in the regional flow system. Earlier models of the basin had difficulty reproducing these features without any hydrochemical data to constrain the rates and distribution of recharge. The objective of this study was to use the large quantity of available hydrochemical data to help calibrate the model parameters, including the recharge rates. The model was constructed using the US Geological Survey's software MODFLOW, MODPATH, and UCODE, and calibrated using 14C activities and the positions of certain flow zones defined by the hydrochemical data. Parameter estimation was performed using a combination of nonlinear regression techniques and a manual search for the minimum difference between field and simulated observations. The calibrated recharge values were substantially smaller than those used in previous models. Results from a 30,000-year transient simulation suggest that recharge was at a maximum about 20,000 years ago and at a minimum about 10,000 years ago. Le calibrage d'un modèle hydrogéologique avec l'aide de données hydrochimiques a démontré que la recharge relativement faible dans le Grand Bassin du Middle Rio est vraisemblablement responsable d'une dépression des eaux souterraines dans le centre du bassin et de la présence d'une quantité substantielle d'eau du Rio Grande dans l'aquifère du Groupe de Santa Fe. Les modèles antérieurs avaient des difficultés à reproduire ses conclusions sans l'aide de données hydrochimiques pour contraindre les taux et la distribution de la recharge. L'objectif de cette étude était d'utiliser une grande quantité de données hydrochimiques permettant de calibrer les paramètres du modèle, et notamment les taux de recharge. Le modèle a été construit avec les logiciels MODFLOW, MODPATH et UCODE, et calibré en utilisant les concentrations en 14C et la position de certaines zones définies par les données hydrochimiques. L'estimation de certains paramètres a été réalisée en utilisant une combinaison de techniques de régression non linéaire et une méthode de recherche exhaustive (Brute Force Search) de l'erreur minimum entre les résultats des observations et les simulations. Les valeurs de la recharge calibrée sont substantiellement plus basses que celles estimées dans les modèles antérieurs. Les résultats d'une simulation en régime transitoire sur 30.000 ans suggèrent que la recharge au maximum de la dernière glaciation (last glacial maximum, LGM) était 10 fois supérieure au taux actuel, mais que la recharge qui a suivit la LGM était plus bas que la recharge actuelle. La calibración de un modelo de aguas subterráneas con el apoyo de datos hidroquímicos ha demostrado que la recarga relativamente baja en la cuenca media del Río Grande es probablemente responsable de una depresión de aguas subterráneas en el centro de la cuenca y de la presencia de una cantidad considerable de agua del Río Grande en el acuífero del Grupo Santa Fe. Los modelos propuestos con anterioridad para la cuenca tenían dificultades para reproducir estas características ya que no tenían datos hidroquímicos que permitieran delimitar los ritmos y distribución de recarga. El objetivo del presente estudio consistió en utilizar una gran cantidad de datos hidroquímicos disponibles para ayudar a calibrar los parámetros del modelo, incluyendo los ritmos de recarga. El modelo se construyó utilizando los modelos MODFLOW, MODPATH, y UCODE del USGS, mientras que la calibración se realizó en base a concentraciones de 14C y a la posición de ciertas zonas definidas con los datos hidroquímicos. La estimación de parámetros se realizó en base a una combinación de técnicas de regresiones no lineares y a una búsqueda a viva fuerza del error mínimo entre los datos observados y los simulados. Los valores de recarga calibrados fueron significativamente más bajos que los estimados en los modelos anteriores. Los resultados de una simulación transitoria de 30,000 años sugieren que la recarga durante la última glacial máxima (LGM) fue diez veces el ritmo moderno, pero que la recarga que ocurrió inmediatamente después de la LGM fue más baja que el ritmo moderno.

Distinción Empírica Entre Engagement y Trabajolismo en Enfermeras Hospitalarias de Japón: Efecto Sobre la Calidad del Sueño y el Desempeño Laboral

PubMed Central

Kubota, Kazumi; Shimazu, Akihito; Kawakami, Norito; Takahashi, Masaya; Nakata, Akinori; Schaufeli, Wilmar B.

2016-01-01

Objetivo El objetivo de este estudio es demostrar la distinción entre engagement y trabajolismo, estudiando su relación con la calidad del sueño y el desempeño laboral. Método Un total de 447 enfermeras de 3 hospitales de Japón fueron entrevistadas mediante un cuestionario autoadministrado que incluía la escala Utrecht (UWES, Utrecht Work Engagement Scale), la Escala de Adicción al Trabajo Holandesa (DUWAS, Dutch Workaholism Scale), preguntas sobre la calidad del sueño (7 ítems) con respecto a (1) dificultad para conciliar el sueño, (2) dificultad para mantener el sueño, (3) despertar temprano por la mañana, (4) dormirse o tomar siestas durante el día, (5) somnolencia diurna excesiva en el trabajo, (6) dificultad para despertarse por la mañana, y (7) despertar cansado en la mañana, y el Cuestionario sobre Salud y Desempeño (CSD) de la Organización Mundial de la Salud. Resultados Los modelos de ecuaciones estructurales demostraron que el engagement se relaciona positivamente con la calidad del sueño y el rendimiento laboral, mientras que el trabajolismo tiene una relación negativa con la calidad del sueño y el desempeño laboral. Conclusión Los resultados indican que el engagement y el trabajolismo son conceptualmente diferentes. El primero tiene una connotación positiva, mientras que el segundo se asocia de manera negativa al bienestar (buena calidad del sueño y buen rendimiento en el trabajo). PMID:26752805

Fotometria WHBY |o lll|/HB de Regiones H 11 Y la HISTORIA de la Formacion ESTELAR Reciente EN la PEQUENA NUBE de Magallanes

NASA Astrophysics Data System (ADS)

Copetti, M. V. F.; Dottori, H. A.

1987-05-01

El ancho equivalente WHβ de la linea de Hβ en emisión y la razón [0 III]/Hβ del par λλ4959, 50 7 A del [0111], fueron medidos en 23 regiones HII de la Peque˜a Nube de Magallanes, por medio de la fotometría fotoeléctrica a través de un sistema de tres filtros interferenciales: dos Hβ , con bandas pasantes de 100 y 30 A, y un [0111] centrado en 5000 A y con banda pasante de 50 A. Las observaciones fueron realizadas con los telescopios de 1.60-m y 0.60-m del Laboratorio Nacional de Astrofísica, Brasópolis, Brasil. Fueron escogidos diafragmas suficientemente grandes para captar la radiación integrada de cada región HII. Las medidas fueron calibradas por comparación a un conjunto de nebulosas planetarias con flujos absolutos bien definidos. A través de la comparación entre los datos observacionales y modelos evolutivos de WHβ y [0 III] /Hβ (Copetti et al.1986', Astr. and Ap., 156, 111), las edades de las regiones HIl fueron estimadas. Basada en la distribución espacial de las edades de regiones HIl, la historia de la formación estelar reciente en la Pequeña Nube de Magallanes es analizada. La similitud de las medidas de WH&beta y [OIII]/WHβ entre las regiones H II observadas sugiere que hubo una explosión de formación estelar a 4±1 x106 años en la Pequeña Nube de Magallanes. (Parcialmente financiado por CNPq).

PubMed

Damián-Bastidas, Narda; Chala-Florencio, Roni J; Chávez-Blanco, Ricardo; Mayta-Tristán, Percy

2016-11-29

Introducción: el etiquetado nutricional ayuda a los consumidores a realizar elecciones más saludables. Sin embargo, este es poco leído, mal interpretado o no usado.Objetivos: evaluar la frecuencia y los factores asociados a la lectura, el uso y la interpretación de etiquetas nutricionales en usuarios de gimnasios en la ciudad de Huancayo, Perú.Materiales y métodos: estudio de corte transversal en 385 usuarios de una cadena de gimnasios. Se midió la interpretación con un test a partir de dos etiquetas, lectura reportada (frecuentemente o no) y el uso reportado para elegir un producto (frecuentemente o no), así como variables demográficas, dietéticas y relacionadas con el gimnasio. Se evaluó la asociación calculando las razones de prevalencias ajustadas en base a las variables significativas del modelo bivariado.Resultados: los participantes tuvieron una edad media de 27,8 ± 9,3 años, 44,7% fueron varones, 49,4% contaron con educación universitaria. El 27,5% reporta leer frecuentemente y dentro de estos el 55,7% reporta usarlas frecuentemente, asimismo el 17,4% sabe interpretar. La lectura se asoció con factores dietéticos y de uso de gimnasio y la interpretación con capacitación previa de lectura de la etiqueta. El uso fue principalmente para seleccionar productos bajos en grasa total (65,1%), alto en proteínas (64,2%) y en menor proporción, productos bajos en sodio (47,2%).Conclusiones: la frecuencia de lectura, el uso y la interpretación de etiquetas nutricionales en usuarios de gimnasio de Huancayo es baja. La capacitación previa de lectura es un factor necesario para una elección saludable. Es necesario establecer estrategias educativas para enseñar a interpretar de forma adecuada las etiquetas nutricionales.

Reacciones de intercambio de carga

NASA Astrophysics Data System (ADS)

Errea, L. F.

Se discute la validez de diversas metodologías y su aplicación al estudio de procesos de intercambio de carga electrónico entre iones y blancos atómicos y moleculares. Para energías de impacto entre 0.05 y 5 eV / amu se emplea el método cuántico de la Coordenada de Reacción Común (CRC). A mayores energías, se utiliza el método semiclásico iconal con un desarrollo de la función de onda dinámica en estados moleculares adiabáticos, modificados con un factor de traslación común (FTC). Estos estados pueden obtenerse con cálculos ab initio o empleando potenciales modelo. Cuando la ionización compite con la transferencia de carga, la inclusión de pseudoestados en estos desarrollos permite calcular simultáneamente las secciones eficaces de ambos procesos. Otra técnica utilizada es el método estadístico CTMC. En el tratamiento de colisiones ión-molécula (diatómica) contrastamos la aplicabilidad de distintos métodos, desde la llamada aproximación Franck-Condon hasta un desarrollo en estados vibrónicos, pasando por la aproximación súbita vibro-rotacional, obteniéndose secciones eficaces de captura electrónica total y a estados individuales, así como secciones de excitación vibracional a estados ligados y del continuo (disociación). En todos los casos es necesario calcular superficies de energía y los correspondientes acoplamientos dinámicos entre los estados. La aplicación de estos métodos permite determinar el grado de contaminación de los haces por estados metaestables en un experimento dado, el cambio en los resultados con diferentes isótopos, la importancia de procesos de doble captura, seguida de explosión culombiana, todo ello con precisión comparable a la de medidas experimentales, para sistemas de interés en distintos tipos de plasmas.

Desarrollo de un instrumento para medir percepciones sobre el contexto de construccion del conocimiento cientifico de estudiantes universitarios de nuevo ingreso

NASA Astrophysics Data System (ADS)

Garcia-Ramirez, Jaime Antonio

En esta investigacion, se desarrollo un instrumento que permite medir percepciones relacionadas al contexto de constriccion del conocimiento cientifico. Se examinaron instrumentos existentes y se encontro que el VOSTS (Views on science, technology, and society), instrumento desarrollado empiricamente en Canada por Aikenhead, Ryan y Fleming, podia traducirse y validarse en el contexto cultural puertorriqueno. El instrumento es extenso, consta de 113 reactivos, cada uno con una premisa basica relacionada a la tematica ciencia, tecnologia y sociedad y un numero de alternativas relacionadas a la premisa que oscila entre siete y trece. Se delimito su utilizacion a los quince reactivos identificados por los autores como relacionados a la construccion social del conocimiento cientifico. Metodologicamente, se procedio a utilizar el modelo de adaptacion intercultural, que permite que el instrumento desarrollado satisfaga las dimensiones de equivalencia semantica, de contenido, tecnica, de criterio y conceptual, atemperado asi al instrumento original. Se cumplio con este proposito mediante la traduccion de la version original en ingles al espanol y viceversa. Se utilizaron comites para examinar la traduccion y la retro-traduccion del instrumento. Se realizo una prueba piloto con estudiantes universitarios de nuevo ingreso, utilizando el instrumento traducido para asegurar su intelegibilidad. La confiabilidad del instrumento se determino mediante la intervencion de un panel de expertos quienes clasificaron las distintas posiciones dentro de cada reactivo en: realista, con merito e ingenua; se transformaron estas opciones en valores numericos lo que permitio establecer una escala Likert para cada una. Se suministro el instrumento a una muestra de estudiantes universitarios de nuevo ingreso con caracteristicas similares a las de la poblacion puertorriquena en cuanto a ejecucion en las pruebas de aptitud verbal y matematica del College Board. Los resultados de sus contestaciones fueron transformados numericamente para poder obtener el coeficiente de correlacion de Spearman-Brown para el instrumento (0.661, p < 0.01). El analisis de las contestaciones de los estudiantes refleja percepciones diversas y, en algunos casos, contradictorias con respecto al contexto de construccion del conocimiento cientifico.

Traumatismo craneoencefálico leve

PubMed Central

Ortega Zufiría, José Manuel; Prieto, Noemí Lomillos; Cuba, Bernardino Choque; Degenhardt, Martin Tamarit; Núñez, Pedro Poveda; López Serrano, María Remedios; López Raigada, Azahara Belén

2018-01-01

Resumen Introducción y objetivo: El TCE leve representa un problema sanitario de enorme interés debido a que un número significativo de enfermos con trauma leve desarrollará complicaciones potencialmente mortales. El objetivo de este estudio ha sido describir una serie amplia de pacientes adultos, mayores de 14 años, que sufren TCE leve, atendidos en el Hospital Universitario de Getafe, entre los años 2010 y 2015 (n = 2480), estudiar el perfil epidemiológico y analizar el diagnóstico y el tratamiento efectuados, así como establecer los principales factores pronósticos que influyen en el resultado final. Método: Se ha realizado un estudio retrospectivo, de revisión de historias clínicas, analizando los resultados con estudio estadístico bivariable y multivariable. Resultados: El TCE leve es más frecuente en varones, y el mecanismo causante más común en nuestro medio es el accidente de tráfico. Se propone un modelo de clasificación de pacientes según grupos de riesgo, que los subdivide en riesgo bajo, intermedio o alto, que se correlaciona bien con la probabilidad de desarrollar complicación intracraneal, y, consecuentemente, con el resultado final. Se discute la indicación de la radiografía simple de cráneo y de la Tomografía Computarizada (TC), así como del ingreso hospitalario para observación neurológica. Conclusiones: En este estudio, la presencia de focalidad neurológica en la exploración clínica, la edad, las alteraciones de la coagulación y la existencia de fractura en la radiografía simple se relacionan con mayor posibilidad de desarrollar lesiones traumáticas intracraneales y con peor pronóstico final. La escala de Glasgow para el Coma es deficitaria en la determinación del resultado final del paciente que sufre TCE, porque no considera variables tales como la amnesia o la pérdida de conocimiento, muy frecuentes en el traumatismo craneoencefálico leve. PMID:29430327

Scale of attitudes toward alcohol - Spanish version: evidences of validity and reliability.

PubMed

Ramírez, Erika Gisseth León; Vargas, Divane de

2017-08-03

validate the Scale of attitudes toward alcohol, alcoholism and individuals with alcohol use disorders in its Spanish version. methodological study, involving 300 Colombian nurses. Adopting the classical theory, confirmatory factor analysis was applied without prior examination, based on the strong historical evidence of the factorial structure of the original scale to determine the construct validity of this Spanish version. To assess the reliability, Cronbach's Alpha and Mc Donalid's Omega coefficients were used. the confirmatory factor analysis indicated the good fit of the scale model in a four-factor distribution, with a cut-off point at 3.2, demonstrating 66.7% of sensitivity. the Scale of attitudes toward alcohol, alcoholism and individuals with alcohol use disorders in Spanish presented robust psychometric qualities, affirming that the instrument possesses a solid factorial structure and reliability and is capable of precisely measuring the nurses' atittudes towards the phenomenon proposed. validar a Escala de atitudes frente ao álcool, ao alcoolismo e a pessoas com transtornos relacionados ao uso do álcool, versão espanhola. estudo metodológico, realizado com 303 enfermeiros colombianos. Seguindo a teoria clássica, foi aplicada a análise fatorial confirmatória sem exploração preliminar, com base na forte evidência histórica da estrutura fatorial do instrumento original para a validação de construto desta versão em espanhol. Para a avaliação da confiabilidade foram utilizados os coeficientes de Alfa de Cronbach e Ômega de Mc Donald. a análise fatorial confirmatória indicou o bom ajuste do modelo da escala na distribuição de quatro fatores, compreendendo 48 itens em sua versão espanhola. Os índices de confiabilidade foram satisfatórios, com ponto de corte observado em 3,2, demonstrando sensibilidade de 66,7%. a Escala de atitudes frente ao álcool, ao alcoolismo e a pessoas com transtornos relacionados ao uso do álcool no idioma espanhol, apresentou qualidades psicométricas robustas, afirmando que se trata de um instrumento com estrutura fatorial e confiabilidade sólidas, capaz de medir com precisão as atitudes dos enfermeiros frente ao fenômeno proposto. validar la Escala de actitudes frente al alcohol, al alcoholismo y a la persona con trastornos relacionados al uso de alcohol en su versión española. estudio de tipo metodológico, realizado con 303 enfermeros colombianos. Siguiendo la teoría clásica, se utilizó análisis factorial confirmatoria sin exploración previa, con base en la fuerte evidencia histórica de la estructura factorial del instrumento original para determinar la validez de constructo de esta versión en español. La confiabilidad se evaluó por los coeficientes de Alfa de Cronbach y Omega de Mc Donald. el análisis factorial confirmatorio indicó buen ajuste del modelo de la escala en la distribución de cuatro factores, comportando 48 ítems en su versión en español. Los índices de confiabilidad fueron satisfactorios, con un punto de corte observado en 3,2, mostrando sensibilidad del 66,7%. la Escala de actitudes frente al alcohol, al alcoholismo y a la persona con trastornos relacionados al uso de alcohol en idioma español presentó cualidades psicométricas robustas, afirmando que se trata de un instrumento con estructura factorial y confiabilidad sólidas, capaz de medir con precisión las actitudes de los enfermeros frente al fenómeno propuesto.

Radio-Observaciones del OH EN la Coma del Cometa Halley Desde EL Hemisferio Sur

NASA Astrophysics Data System (ADS)

Silva, A. M.; Bajaja, E.; Morras, R.; Cersosimo, J. C.; Martin, M. C.; Arnal, E. M.; Poppel, W. G. L.; Colomb, F. R.; Mazzaro, J.; Olalde, J. C.; Boriakoff, V.; Mirabel, I. F.

1987-05-01

Se utilizó una antena de 30 metros del Instituto Argentino de Radioastronomía para observaciones diarias Cf ebrero a abril de 1986) de la transición en 1667 MHz ( λ = 18 cm) del OH en la coma del cometa Halley. De las observaciones realizadas se concluye: 1) El número promedio de moléculas de OH en la coma durante 37 días de observación fue de (8.9±3.5)x1034 moléculas, lo que implica una tasa de producción promedio de OH de 1.8x1029 moléculas seg-1 y consecuentemente una pérdida de masa promedio de 17±6 toneladas seg-1 . Este valor está de acuerdo con las mediciones realizadas por las sondas Vega y Giotto. 2) El monitoreo desde el lAR revela la existencia de variaciones bruscas en los flujos de absorción del OH. Estas variaciones son consistentes con los modelos que representan la producción gaseosa a partir de ejecciones y/o desprendimientos discretos de materia congelada del núcleo. 3) Las variaciones en la densidad de flujo son consistentes con las estimaciones de los tiem- pos de vida medios del H2O y del OH en presencia del campo de radiación solar. 4) Se encuentra una correlación entre la intensidad del flujo absorbido y anisotropías en Ia dinamica de la coma.

Numerical Results for a Polytropic Cosmology Interpreted as a Dust Universe Producing Gravitational Waves

NASA Astrophysics Data System (ADS)

Klapp, J.; Cervantes-Cota, J.; Chauvet, P.

1990-11-01

RESUMEN. A nivel cosmol6gico pensamos que se ha estado prodticiendo radiaci6n gravitacional en cantidades considerables dentro de las galaxias. Si los eventos prodnctores de radiaci6n gravitatoria han venido ocurriendo desde Ia epoca de Ia formaci6n de las galaxias, cuando menos, sus efectos cosmol6gicos pueden ser tomados en cuenta con simplicidad y elegancia al representar la producci6n de radiaci6n y, por consiguiente, su interacci6n con materia ordinaria fenomenol6gicamente a trave's de una ecuaci6n de estado politr6pica, como lo hemos mostrado en otros trabajos. Presentamos en este articulo resultados nunericos de este modelo. ABSTRACT A common believe in cosmology is that gravitational radiation in considerable quantities is being produced within the galaxies. Ifgravitational radiation production has been running since the galaxy formation epoch, at least, its cosmological effects can be assesed with simplicity and elegance by representing the production of radiation and, therefore, its interaction with ordinary matter phenomenologically through a polytropic equation of state as shown already elsewhere. We present in this paper the numerical results of such a model. K words: COSMOLOGY - GRAVITATION

Bifurcación de las soluciones de vientos impulsados por radiación en estrellas Be: formación de líneas

NASA Astrophysics Data System (ADS)

Curé, M.; Rial, D.; Cidale, L.; Venero, R.

Se ha estudiado la topología de la ecuación hidrodinámica no-lineal que describe el perfil de velocidades de vientos impulsados por radiación en estrellas tempranas. Al aplicar este modelo a estrellas Be se encuentra que existen dos tipos De soluciones: la estándar, que describe el viento polar, y una nueva, que describe un viento más denso y lento y que explicaría el disco que se encuentra alrededor de estos objetos. Existe una región de transición en donde ambas soluciones coexisten (bifurcación}). Ambas soluciones satisfacen en esta región las mismas condiciones de borde. Para estas dos soluciones se han obtenido los perfiles de líneas de hidrógeno del visible y del IR, resolviendo el transporte de radiación en el ``comoving frame". Para la solución estándar, se obtienen perfiles con componentes en emisión, mientras que para la nueva solución se obtienen perfiles en absorción. Se comparan cualitativamente los resultados con las observaciones.

Confirmatory factor analysis of the Appraisal of Self-Care Agency Scale - Revised.

PubMed

Stacciarini, Thaís Santos Guerra; Pace, Ana Emilia

2017-01-30

to analyze the factor structure of the Appraisal of Self-Care Agency Scale-Revised (ASAS-R), adapted for Brazil. methodological study conducted with 150 individuals with diabetes mellitus cared for by the Family Health Strategy, most of whom are elderly with low educational levels. The test of the hypothesis concerning the confirmatory factor composition of the ASAS-R was performed using latent variables structural equations. the model's goodness-of-fit indexes were satisfactory (χ2 = 259.19; χ2/g.l = 2.97, p < 0.001; GFI = 0.85; RMR = 0.07; RMSEA = 0.09); the factor loads were greater than 0.40; and most item-to-factor-correlations presented moderate to strong magnitude (0.34 to 0.58); total alpha value was 0.74, while the alpha of the three factors were 0.69, 0.38 and 0.69, respectively. the scale's factor structure presented satisfactory validity and reliability results, with the exception of one factor. Application of this scale to samples of the general population is desirable in order to strengthen analyses of internal consistency and the dimensionality of the factor structure. This study is expected to contribute to further studies addressing the self-care agency construct and the development of the ASAS-R. analisar a estrutura fatorial da escala de avaliação da capacidade de autocuidado, Appraisal of Self Care Agency Scale-Revised (ASAS-R), adaptada no Brasil. estudo metodológico conduzido em 150 usuários com diabetes mellitus, maioria idosos e com baixa escolaridade, em seguimento na Estratégia Saúde da Família. O teste de hipótese da composição fatorial confirmatória da escala ASAS-R foi realizado via modelo de equações estruturais para variáveis latentes. os valores dos índices de ajuste do modelo foram satisfatórios (χ2 de 259,19; χ2/g.l de 2,97, p < 0,001; GFI = 0,85; RMR = 0,07; RMSEA = 0,09), as cargas fatoriais foram superiores a 0,40, maioria das correlações item e fator foi de moderada a forte magnitude (0,34 a 0,58) e os valores de alfa total de 0,74 e dos três fatores de 0,69, 0,38 e 0,69, respectivamente. estrutura fatorial da escala com resultados satisfatórios de validade e de confiabilidade, exceto um de seus fatores. É desejável que essa Escala seja aplicada em amostras da população geral, para fortalecer as análises de consistência interna e de dimensionalidade da estrutura fatorial, e espera-se que este estudo possa contribuir no avanço de outras pesquisas que trabalham com o construto de capacidade de autocuidado e no desenvolvimento da Escala ASAS-R. analizar la estructura factorial de la escala de evaluación de la capacidad de autocuidado, Appraisal of Self Care Agency Scale-Revised (ASAS-R), adaptada en Brasil. estudio metodológico conducido en 150 usuarios con diabetes mellitus, mayoría de ancianos y con baja escolaridad, acompañados por la Estrategia Salud de la Familia. El test de hipótesis de la composición factorial confirmatoria de la escala ASAS-R fue realizado por medio del modelo de ecuaciones estructurales para variables latentes. los valores de los índices de ajuste del modelo fueron satisfactorios (χ2 de 259,19; χ2/g.l de 2,97, p < 0,001; GFI = 0,85; RMR = 0,07; RMSEA = 0,09), las cargas factoriales fueron superiores a 0,40, la mayoría de las correlaciones ítem y factor varió de moderada a fuerte magnitud (0,34 la 0,58); valores de alfa total de 0,74 y de los tres factores de 0,69, 0,38 y 0,69, respectivamente. la estructura factorial de la escala obtuvo resultados satisfactorios de validez y de confiabilidad, excepto uno de sus factores. Es deseable que esa escala sea aplicada en muestras de la población general, para fortalecer los análisis de consistencia interna y de dimensionalidad de la estructura factorial; y se espera que este estudio pueda contribuir para avanzar en nuevas investigaciones que vengan a trabajar con el constructo de capacidad de autocuidado y con el desarrollo de la escala ASAS-R.

Implementación de un modelo de capacitación multimedial para brindar orientación alimentaria a los beneficiarios de un programa de ayuda social en México.

PubMed

Amaya-Castellanos, Maritza Alejandra; Morales-Ruan, María Del Carmen; Uribe-Carvajal, Rebeca; Jiménez-Aguilar, Alejandra; Salazar-Coronel, Araceli Apolonia; Martínez-Tapia, Brenda; Shamah-Levy, Teresa

2018-03-01

Introducción: Se implementó un modelo de capacitación en orientación alimentaria para la población beneficiaria y el personal operativo del Programa de Abasto Rural (PAR) de Diconsa, el cual es una iniciativa social de ayuda alimentaria que abastece productos básicos y complementarios, además de brindar capacitación en localidades de alta marginación en México. Objetivo: Documentar la utilización de la Metodología de Capacitación Multimedial (MCM) en el desarrollo de un esquema de capacitación sobre orientación alimentaria y su implementación en la población beneficiaria del PAR, a través de la propia estructura operativa del PAR. Metodología: El modelo se fundamenta en la MCM, integrada por cuatro elementos didácticos e indivisibles que conforman el paquete pedagógico multimedial (PPM), compuesto a su vez por tres videos y rotafolios, material impreso, prácticas y las relaciones interpersonales. Los ejes temáticos fueron: alimentación correcta para una vida saludable, alimentación materno-infantil, elecciones saludables y gasto familiar. El modelo fue replicado en cascada en los tres niveles operativos del PAR (responsables de capacitación, supervisores operativos y beneficiarios del PAR), con un componente de multiplicación horizontal, e implementado como piloto en cuatro estados de México. Resultados: Se observó un cambio positivo sobre los conocimientos en alimentación correcta en todos los niveles de capacitación, principalmente en los beneficiarios del PAR. La evaluación del proceso mostró conocimientos previos de los responsables de capacitación en los temas, buen desempeño como facilitadores, y habilidades de presentación y manejo del grupo de los supervisores operativos. A partir de las evaluaciones y del acompañamiento en la prueba piloto, fueron modificados las actividades, las estrategias y los materiales educativos del PPM. Conclusiones: La capacitación multimedial y la educación nutricional promueven procesos de cambio y desarrollo comunitario, posibles a través de la toma de conciencia y la puesta en práctica de acciones que favorecen la salud.

78 FR 30399 - United States v. Anheuser-Busch InBev SA/NV, Grupo Modelo S.A.B de C.V.; Proposed Final Judgment...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-22

..., Mexico. Modelo is the third-largest brewer of beer sold in the United States. Modelo's Corona Extra brand... include Corona Light, Modelo Especial, Negra Modelo, Victoria, and Pacifico. 19. ABI currently holds a 35... such as Dogfish Head, Flying Dog, and also imported beers, the best selling of which is Modelo's Corona...

Explicación de las disparidades raciales en la salud neonatal en Brasil*

PubMed Central

Nyarko, Kwame A.; López-Camelo, Jorge; Castilla, Eduardo E.; Wehby, George L.

2015-01-01

Objetivos. Buscamos cuantificar la manera en que los efectos socioeconómicos, demográficos, geográficos y de atención de salud explican las disparidades raciales en las tasas de bajo peso al nacer y prematuridad en Brasil. Métodos. Utilizamos una muestra de 8 949 niños nacidos entre 1995 y el 2009 en 15 ciudades y 7 provincias de Brasil. Nos centramos en las disparidades en la prevalencia de bajo peso al nacer (< 2 500 g) y prematuridad (< 37 semanas de gestación) en recién nacidos de ascendencia solo africana o mezclada con otras ascendencias y de ascendencia solo europea. Usamos un modelo de descomposición para cuantificar la contribución de los factores conceptualmente pertinentes a esas disparidades. Resultados. El modelo permitió explicar entre 45% y 94% de las disparidades en cuanto al bajo peso al nacer y entre 64% y 94% de las disparidades en cuanto a la prematuridad entre los grupos de ascendencia africana y de ascendencia europea. Las diferencias en el uso de atención prenatal y en la ubicación geográfica fueron los factores más importantes, seguidos por las diferencias socioeconómicas. El modelo permitió explicar la mayoría de las disparidades en los recién nacidos de ascendencia africana mezclada y parte de las disparidades en los de ascendencia solo africana. Conclusiones. En las políticas públicas para mejorar la salud infantil se deben abordar las diferencias en cuanto a la atención prenatal y la ubicación geográfica a fin de reducir las disparidades en materia de salud entre los recién nacidos de ascendencia africana y los de ascendencia europea en Brasil.

Occurrence of springs in massifs of crystalline rocks, northern Portugal

NASA Astrophysics Data System (ADS)

Pacheco, Fernando António Leal; Alencoão, Ana Maria Pires

2002-02-01

An inventory of artesian springs emerging from fractures (fracture springs) was conducted in the Pinhão River Basin and Morais Massif, northern Portugal, comprising an area of approximately 650 km2. Over 1,500 springs were identified and associated with geological domains and fracture sets. Using cross-tabulation analysis, spring distributions by fracture sets were compared among geological environments, and the deviations related to differences in rock structure and, presumably, to differences in deformational histories. The relation between spring frequencies and rock structures was further investigated by spectral determination, the model introduced in this study. Input data are the spring frequencies and fracture lengths in each geological domain, in addition to the angles between fracture strikes and present-day stress-field orientation (θ). The model's output includes the so-called intrinsic densities, a parameter indexing spring occurrence to factors such as fracture type and associated deformational regime and age. The highest densities (12.2 springs/km of lineament) were associated with young shear fractures produced by brittle deformation, and the lowest (0.1) with old tensional and ductile fractures. Spectral determination also relates each orientation class to a dominant structural parameter: where spring occurrence is controlled by θ, the class is parallel to the present-day stress-field orientation; where the control is attributed to the length of fractures, the spring occurrence follows the strike of large-scale normal faults crossing the region. Résumé. Un inventaire des sources artésiennes émergeant de fractures (sources de fractures) a été réalisé dans le bassin de la rivière Pinhão et dans le massif de Morais, dans le nord du Portugal, dans une région couvrant environ 650 km2. Plus de 1,500 sources ont été identifiées et associées à des domaines géologiques et à des ensembles de fractures. Grâce à une analyse de tableaux croisés, les distributions des sources par ensemble de fractures ont été comparées aux situations géologiques et aux écarts liés aux différences dans les structures des roches et, probablement, aux différences dans leurs histoires de déformations. Les relations entre la fréquence des sources et la structure des roches ont été étudiées ensuite par détermination spectrale, modèle présenté dans cette étude. Les données d'entrée sont les fréquences des sources et les longueurs des fractures dans chaque domaine géologique, en plus des angles entre directions de fractures et orientation du champ de contraintes actuel (θ). La sortie du modèle donne les densités dites intrinsèques, un paramètre indexant l'existence d'une source à des facteurs tels que le type de fracture et le régime et l'âge associés de la déformation. Les densités les plus fortes (12,2 sources par km de linéament) ont été associées à des fractures jeunes produites par des déformations lentes, et les plus faibles (0,1) aux fractures anciennes ductiles et de tension. La détermination spectrale associe également chaque classe d'orientation à un paramètre structural dominant: quand la présence d'une source est contrôlée par θ, la classe est parallèle à l'orientation actuelle du champ de contrainte; lorsque le contrôle est attribué à la longueur des fractures, la présence de sources suit le plan des failles normales à grande échelle traversant la région. Resumen. Se ha llevado a cabo un inventario de manantiales emergentes de fracturas (manantiales de fracturas) en la cuenca del Río Pinhão y en el Macizo de Morais. El área estudiada ocupa unos 650 km2 y se halla al Norte de Portugal. Se ha identificado más de 1.500 manantiales, los cuales han sido asociados con dominios geológicos y conjuntos de fracturas. Mediante el Análisis de la Tabulación Cruzada, se ha comparado la distribución de los manantiales por conjuntos de fracturas entre ambientes geológicos, así como las desviaciones relacionadas con diferencias en la estructura de la roca y, presumiblemente, en las historias de deformación. Se profundizó en la relación entre la frecuencia de los manantiales y las estructuras de la roca por medio de la Determinación Espectral, que es un modelo introducido en el presente estudio. Los datos de entrada son las frecuencias de los manantiales y la longitud de las fracturas en cada dominio geológico, además de los ángulos entre las direcciones de las fracturas y la orientación actual del campo de tensiones. Los resultados del modelo incluyen las denominadas densidades intrínsecas, parámetro que cuantifica la existencia de manantiales en función de factores como el tipo de fractura y el régimen y edad de deformación asociados. Las densidades mayores (12,2 manantiales por kilómetro de lineamiento) fueron atribuidas a fracturas jóvenes de cizalla causadas por deformación frágil, y las menores (valor 0,1) con fracturas antiguas y dúctiles. La Determinación Espectral también relaciona cada clase de orientación con un parámetro estructural dominante: donde la existencia de fracturas está dominada por el campo actual de tensiones, la clase es paralela a la orientación presente de dicho campo; donde domina la longitud de las fracturas, sigue la dirección de las fallas normales de gran escala que atraviesan la región.

Development of a sharp interface model that simulates coastal aquifer flow with the coupled use of GIS

NASA Astrophysics Data System (ADS)

Gemitzi, Alexandra; Tolikas, Demetrios

A simulation program, which works seamlessly with GIS and simulates flows in coastal aquifers, is presented in the present paper. The model is based on the Galerkin finite element discretization scheme and it simulates both steady and transient freshwater and saltwater flow, assuming that the two fluids are separated by a sharp interface. The model has been verified in simple cases where analytical solutions exist. The simulation program works as a tool of the GIS program, which is the main database that stores and manages all the necessary data. The combined use of the simulation and the GIS program forms an integrated management tool offering a simpler way of simulating and studying saline intrusion in coastal aquifers. Application of the model to the Yermasogia aquifer illustrates the coupled use of modeling and GIS techniques for the examination of regional coastal aquifer systems. Pour étudier un système aquifère côtier, nous avons développé un modèle aux éléments finis en quasi 3-D qui simule les écoulements d'eau douce et d'eau salée en régime aussi bien permanent que transitoire. Les équations qui les régissent sont discrétisées par un schéma de discrétisation de Garlekin aux éléments finis. Le modèle a été vérifié dans des cas simples où il existe des solutions analytiques. Toutes les données nécessaires sont introduites et gérées grâce à un logiciel de gestion de SIG. Le programme de simulation est utilisé comme un outil du logiciel de SIG, constituant ainsi un outil de gestion intégrée dont le but est de simuler et d'étudier l'intrusion saline dans les aquifères côtiers. L'application du modèle à l'aquifère de Yermasogia illustre l'utilisation couplée de la modélisation et des techniques de SIG pour l'étude des systèmes aquifères côtiers régionaux. Se ha desarrollado un modelo casi tridimensional de elementos finitos para simular el flujo de agua dulce y salada, tanto en régimen estacionario como en transitorio, en sistemas acuíferos costeros, bajo la hipótesis de separación por medio de una interfaz abrupta. Las ecuaciones del modelo han sido discretizadas mediante un esquema de Galerkin de discretización en elementos finitos. El modelo ha sido verificado en casos sencillos para los que existe solución analítica. Todos los datos necesarios se introducen y gestionan con un Sistema de Información Geográfica [SIG] por ordenador. El programa de simulación forma parte del programa de SIG, constituyendo una herramienta integrada de gestión para estudiar la intrusión salina en acuíferos costeros. La aplicación del modelo al acuífero de Yermasogia ilustra el uso acoplado de las técnicas de modelación y de SIG con el fin de examinar sistemas acuíferos costeros a escala regional.

Is the Dark Side of the Moon Ever Illuminated by the Sun? (Breton Title: O Lado Escuro da Lua Nunca Apanha Sol?) El Lado Oscuro de la Luna Nunca Toma Sol?

NASA Astrophysics Data System (ADS)

Giovannini, Odilon; Pellenz, Daiana; Catelli, Francisco

2014-07-01

This work presents the elaboration of an answer to the question "Is the dark side of the moon ever illuminated by the sun?", in which issues related to the students' conceptions, how they arise, and the core elements that constitute a "good answer" are considered. These issues are initially elaborated from a literature review of the research in the field; then, and also based on this review, a didactic model that involves the relative motions of the Earth - Moon - Sun system is proposed. A description of the application of this model in a learning environment within middle school students is described. This work confirms the students' initial concepts described in the literature; on the other hand, the questions asked by students during the activity provide evidence that meaningful learning, at least to some degree, has occurred. Este trabalho apresenta a elaboração de uma resposta à pergunta "O lado escuro da Lua nunca apanha sol?" na qual são consideradas questões relacionadas às concepções iniciais dos alunos, de onde elas surgem e os elementos centrais que constituem uma "boa resposta". Essas questões são tratadas, inicialmente, a partir de uma revisão da literatura sobre pesquisas na área e, em seguida, também com base nessa revisão, um objeto modelo didático que envolve os movimentos relativos do sistema Terra - Lua - Sol é proposto. Uma descrição detalhada da aplicação deste modelo em um ambiente de aprendizagem com alunos do ensino fundamental é relatada. As concepções iniciais apresentadas na literatura se confirmam e os questionamentos feitos pelos estudantes por ocasião da aplicação do modelo fornecem indícios de que uma aprendizagem significativa, pelo menos em algum grau, ocorreu. El artículo se presenta el desarrollo de una respuesta a la pregunta "¿El lado oscuro de la luna nunca toma sol?", en la que se consideran algunas cuestiones vinculadas que se refieren a las concepciones iniciales de los estudiantes, dónde surgen y los elementos básicos que componen una "respuesta correcta". Estas cuestiones se tratan inicialmente a partir de una revisión bibliográfica de la investigación en el área; seguidamente, y también sobre la base de ésta revisión, se propone un modelo didáctico que ejemplifica los movimientos relativos del sistema Tierra - Luna - Sol. Se describe a continuación una aplicación de este modelo en un entorno de aprendizaje con alumnos del ciclo primario. Los conceptos iniciales presentados en la literatura se confirman y las cuestiones planteadas por los estudiantes durante la implementación del modelo proporcionan evidencia de que se ha producido un aprendizaje significativo, al menos en cierta medida.

Complications of central venous catheter in patients transplanted with hematopoietic stem cells in a specialized service.

PubMed

Barretta, Lidiane Miotto; Beccaria, Lúcia Marinilza; Cesarino, Cláudia Bernardi; Pinto, Maria Helena

2016-06-07

to identify the model, average length of stay on site and complications of central venous catheter in patients undergoing transplant of hematopoietic stem cells and verify the corresponding relationship between the variables: age, gender, medical diagnosis, type of transplant, implanted catheter and insertion site. a retrospective and quantitative study with a sample of 188 patients transplanted records between 2007 and 2011. the majority of patients used Hickman catheter with an average length of stay on site of 47.6 days. The complication fever/bacteremia was significant in young males with non-Hodgkin's lymphoma undergoing autologous transplant, which remained with the device for a long period in the subclavian vein. nurses should plan with their team the minimum waiting time, recommended between the catheter insertion and start of the conditioning regimen, as well as not to extend the length of time that catheter should be on site and undertake their continuing education, focusing on the prevention of complications. identificar o modelo, tempo médio de permanência e complicações de cateter venoso central em pacientes submetidos ao transplante de células-tronco hematopoiéticas e verificar a relação de correspondência entre as variáveis: idade, sexo, diagnóstico médico, tipo de transplante, cateter implantado e local de inserção. retrospectivo, quantitativo, com amostra de prontuários de 188 pacientes transplantados, entre 2007 e 2011. a maioria dos pacientes utilizou o cateter de Hickman com permanência média de 47,6 dias. A complicação febre/bacteremia foi significante em jovens do sexo masculino, com linfoma não Hodgkin, submetidos ao transplante autólogo, que permaneceram com o dispositivo por longo período, em veia subclávia. os enfermeiros devem planejar com a equipe o aguardo do tempo mínimo preconizado entre o implante do cateter e início do regime de condicionamento, assim como não estender o período de permanência e realizar educação permanente, enfocando a prevenção das complicações. identificar el modelo, el tiempo medio de permanencia y las complicaciones del catéter venoso central en pacientes sometidos a trasplante de células madre hematopoyéticas y estimar la relación de correspondencia entre las variables: edad, sexo, diagnóstico médico, tipo de trasplante, catéter implantado y sitio de inserción. estudio retrospectivo y cuantitativo con una muestra de registros de 188 pacientes trasplantados entre 2007 y 2011. la mayoría de los pacientes utilizó el catéter Hickman con una permanencia media de 47,6 días. La complicación fiebre/bacteriemia fue significativa en los varones jóvenes con linfoma no Hodgkin sometidos a trasplante autólogo, que permanecieron con el dispositivo durante un largo período en la vena subclavia. los enfermeros deben planificar con el equipo, el tiempo de espera mínimo recomendado entre la inserción del catéter y el inicio del tratamiento de condicionamiento, así como no extender el período de permanencia del catéter y realizar su formación continua, centrándose en la prevención de complicaciones.

Simulation of regional-scale groundwater flow in the Azul River basin, Buenos Aires Province, Argentina

NASA Astrophysics Data System (ADS)

Varni, Marcelo R.; Usunoff, Eduardo J.

A three-dimensional modular model (MODFLOW) was used to simulate groundwater flow in the Azul River basin, Buenos Aires Province, Argentina, in order to assess the correctness of the conceptual model of the hydrogeological system. Simulated heads satisfactorily match observed heads in the regional water-table aquifer. Model results indicate that: (1) groundwater recharge is not uniform throughout the region but is best represented by three recharge rates, decreasing downgradient, similar to the distribution of soils and geomorphological characteristics; and (2) evapotranspiration rates are larger than previous estimates, which were made by using the Thornthwaite-Mather method. Evapotranspiration rates estimated by MODFLOW agree with results of independent studies of the region. Model results closely match historical surface-flow records, thereby suggesting that the model description of the aquifer-river relationship is correct. Résumé Un modèle modulaire tridimensionnel (MODFLOW) a été utilisé pour simuler les écoulements souterrains dans le bassin de la rivière Azul (Province de Buenos Aires, Argentine), dans le but d'évaluer la justesse du modèle conceptuel du système hydrogéologique. La piézométrie simulée s'ajuste de façon satisfaisante à celle observée pour l'ensemble de la nappe. Les résultats du modèle indiquent que: (1) la recharge de la nappe n'est pas uniforme sur toute la région, mais qu'elle est mieux approchée par trois valeurs différentes, décroissant vers l'aval-gradient, en suivant la même distribution que les sols et les caractéristiques géomorphologiques et (2) l'évapotranspiration est nettement plus importante que prévu initialement à partir de la méthode de Thornthwaite-Mather. Les valeurs d'évapotranspiration fournies par MODFLOW concordent bien avec les résultats d'autres études portant sur la région. Les résultats du modèle reproduisent convenablement les chroniques de débit des écoulements de surface, suggérant ainsi que la description par le modèle des relations rivière-nappe est correcte. Resumen Se ha utilizado el modelo MODFLOW, del Servicio Geológico de los Estados Unidos, para simular el flujo de agua subterránea en la cuenca del arroyo del Azul, Provincia de Buenos Aires, Argentina, con el objeto de evaluar el modelo hidrogeológico conceptual. Los niveles hidráulicos simulados ajustan satisfactoriamente con los niveles observados. Los resultados de la simulación indican que: (1) la recarga no es uniforme, sino que puede caracterizarse con tres zonas en las que sus valores decrecen en la medida en que decrece la pendiente, que guarda similitud con la distribución de suelos y características geomorfológicas y (2) la evapotranspiración sería mayor que la estimada en estudios previos, en los que se utilizó el método de Thornthwaite-Mather. La evapotranspiración estimada mediante la presente simulación concuerda con resultados de varios estudios independientes en la región. Respecto de la relación acuífero-río, existe un muy buen ajuste entre los aportes del acuífero al río simulados y los valores históricos de caudal base.

Evaluation of clinical information modeling tools.

PubMed

Moreno-Conde, Alberto; Austin, Tony; Moreno-Conde, Jesús; Parra-Calderón, Carlos L; Kalra, Dipak

2016-11-01

Clinical information models are formal specifications for representing the structure and semantics of the clinical content within electronic health record systems. This research aims to define, test, and validate evaluation metrics for software tools designed to support the processes associated with the definition, management, and implementation of these models. The proposed framework builds on previous research that focused on obtaining agreement on the essential requirements in this area. A set of 50 conformance criteria were defined based on the 20 functional requirements agreed by that consensus and applied to evaluate the currently available tools. Of the 11 initiative developing tools for clinical information modeling identified, 9 were evaluated according to their performance on the evaluation metrics. Results show that functionalities related to management of data types, specifications, metadata, and terminology or ontology bindings have a good level of adoption. Improvements can be made in other areas focused on information modeling and associated processes. Other criteria related to displaying semantic relationships between concepts and communication with terminology servers had low levels of adoption. The proposed evaluation metrics were successfully tested and validated against a representative sample of existing tools. The results identify the need to improve tool support for information modeling and software development processes, especially in those areas related to governance, clinician involvement, and optimizing the technical validation of testing processes. This research confirmed the potential of these evaluation metrics to support decision makers in identifying the most appropriate tool for their organization. Los Modelos de Información Clínica son especificaciones para representar la estructura y características semánticas del contenido clínico en los sistemas de Historia Clínica Electrónica. Esta investigación define, prueba y valida un marco para la evaluación de herramientas informáticas diseñadas para dar soporte en la en los procesos de definición, gestión e implementación de estos modelos. El marco de evaluación propuesto se basa en una investigación previa para obtener consenso en la definición de requisitos esenciales en esta área. A partir de los 20 requisitos funcionales acordados, un conjunto de 50 criterios de conformidad fueron definidos y aplicados en la evaluación de las herramientas existentes. Un total de 9 de las 11 iniciativas identificadas desarrollando herramientas para el modelado de información clínica fueron evaluadas. Los resultados muestran que las funcionalidades relacionadas con la gestión de tipos de datos, especificaciones, metadatos y mapeo con terminologías u ontologías tienen un buen nivel de adopción. Se identifican posibles mejoras en áreas relacionadas con los procesos de modelado de información. Otros criterios relacionados con presentar las relaciones semánticas entre conceptos y la comunicación con servidores de terminología tienen un bajo nivel de adopción. El marco de evaluación propuesto fue probado y validado satisfactoriamente contra un conjunto representativo de las herramientas existentes. Los resultados identifican la necesidad de mejorar el soporte de herramientas a los procesos de modelado de información y desarrollo de software, especialmente en las áreas relacionadas con gobernanza, participación de profesionales clínicos y la optimización de la validación técnica en los procesos de pruebas técnicas. Esta investigación ha confirmado el potencial de este marco de evaluación para dar soporte a los usuarios en la toma de decisiones sobre que herramienta es más apropiadas para su organización. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Número de ganglios linfáticos metastásicos como determinante de los resultados después de prostatectomía radical de rescate para el cáncer de próstata de radiación recurrente

PubMed Central

Gugliemetti, G; Sukhu, R; Conca Baenas, M A.; Meeks, J; Sjoberg, D D.; Eastham, J A.; Scardino, P T.; Touijer, K

2017-01-01

Resumen Antecedentes La presencia de metástasis en los ganglios linfáticos (MGL) en la prostatectomía radical de rescate (PRs) se asocia con un mal pronóstico. Los factores predictivos de resultados en este contexto siguen siendo indeterminados. El objetivo fue evaluar el papel de número de ganglios linfáticos positivos sobre el resultado de los pacientes con MGL después de PRs y para el cáncer de próstata de radio-recurrente. Material y métodos Se analizaron los datos de una cohorte consecutiva de 215 hombres tratados con PRr en una sola institución. Se utilizaron los modelos de regresión de riesgos proporcionales de Cox univariante para la recurrencia bioquímica (RBQ) y los resultados metastásicos, con el antígeno prostático específico, la puntuación de Gleason, la extensión extraprostática, la invasión de vesículas seminales, el tiempo entre la terapia de radiación y PRr y el número de ganglios positivos como factores predictivos. Resultados De los 47 pacientes con MGL, 37 desarrollaron RBQ, 11 desarrollaron metástasis a distancia y 4 fallecieron con una mediana de seguimiento de 2,3 años para los supervivientes. El riesgo de metástasis aumentó con mayores niveles preoperatorios de PSA (HR 1,19 por 1 ng/ml; IC del 95%: 1,06, 1,34; p = 0,003). Los factores predictivos restantes no alcanzaron niveles convencionales de significación. Sin embargo, la eliminación de 3 o más ganglios linfáticos positivos demostró una asociación positiva, como se esperaba, con enfermedad metastásica (HR 3,44, IC: 0,91, 13,05; p = 0,069) en comparación con uno o dos ganglios positivos. Del mismo modo, la presencia de extensión extraprostática, invasión de vesículas seminales y grado de Gleason superior a 7 también demostraron una asociación positiva con un mayor riesgo de metástasis, con índices de riesgo de 3,97 (IC del 95% 0,50; 31,4; p = 0,2), 3,72 (IC 95% 0,80, 17,26; p = 0,1) y 1,45 (IC del 95% 0,44, 4,76; p = 0,5), respectivamente. Conclusiones En los pacientes con MGL después de PRr para el cáncer de próstata radiorecurrente, es probable que el riesgo de metástasis a distancia esté influenciado por el número de ganglios positivos (3 o más), alto PSA preoperatorio, grado de Gleason y estadio patológico avanzado. Estos resultados son consistentes con los hallazgos del número de ganglios (de 1 a 2 frente a 3 o más ganglios positivos) como un indicador pronóstico después de la prostatectomía radical primaria y fortalecen la petición de una revisión de la estadificación ganglionar del cáncer de próstata. PMID:27184342

Fatigue in children and adolescents with cancer from the perspective of health professionals.

PubMed

Silva, Michele Cristina Miyauti da; Lopes, Luís Carlos; Nascimento, Lucila Castanheira; Lima, Regina Aparecida Garcia de

2016-08-29

to investigate health professionals' knowledge about the concept, assessment and intervention in fatigue in children and adolescents with cancer. exploratory study with qualitative approach, with 53 health professionals (10 nurses, 33 assistant nurses, 3 physicians, 3 nutritionists, 2 psychologists and 2 physical therapists). Semi structured interviews were held, which were recorded and analyzed by means of inductive thematic content analysis. the data were organized around three themes: knowledge of health professionals about fatigue; identification of fatigue and interventions to relieve fatigue. the results indicate the health professionals' limited knowledge about fatigue, as well as the lack of investment in their training and continuing education. Most of all, the lack of research on the theme in the Brazilian context remains a barrier to support improvements in care for this symptom in children and adolescents with cancer. investigar quais conhecimentos os profissionais de saúde têm acerca do conhecimento, avaliação e intervenção sobre a fadiga em crianças e adolescentes com câncer. estudo exploratório com abordagem qualitativa, realizado com 53 profissionais de saúde (10 enfermeiros, 33 auxiliares de enfermagem, 3 médicos, 3 nutricionistas, 2 psicólogos e 2 fisioterapeutas). Foram conduzidas entrevistas semiestruturadas as quais foram gravadas e analisadas por meio do modelo de análise de conteúdo do tipo temática indutiva. os dados foram organizados ao redor de três temas: conhecimento dos profissionais da saúde sobre fadiga; identificação da fadiga e intervenções para o alívio da fadiga. os achados apontam para o conhecimento limitado dos profissionais de saúde sobre fadiga, bem como para o pouco investimento em educação continuada e permanente. Sobretudo, a escassez de estudos sobre o assunto no cenário brasileiro ainda é uma barreira para oferecer subsídios para melhoria deste sintoma em crianças e adolescentes com câncer. investigar cuales conocimientos los profesionales de salud poseen acerca del conocimiento, la evaluación e intervención sobre la fatiga en niños y adolescentes con cáncer. estudio exploratorio con aproximación cualitativa, desarrollado con 53 profesionales de salud (10 enfermeros, 33 auxiliares de enfermería, 3 médicos, 3 nutricionistas, 2 psicólogos y 2 fisioterapeutas). Fueron conducidas entrevistas semi-estructuradas, que fueron grabadas y analizadas mediante el modelo de análisis de contenido del tipo temático inductivo. los datos fueron organizados alrededor de tres temas: conocimiento de los profesionales de la salud acerca de la fatiga; identificación de la fatiga e intervenciones para el alivio de la fatiga. los hallazgos indican el conocimiento limitado de los profesionales de salud sobre fatiga, además de la poca inversión en educación continuada y permanente. Sobretodo, la escasez de estudios sobre el tema en el escenario brasileño sigue siendo una barrera para ofrecer apoyo para mejorar este síntoma en niños y adolescentes con cáncer.

The nature of the Ailao Shan-Red River (ASRR) shear zone: Constraints from structural, microstructural and fabric analyses of metamorphic rocks from the Diancang Shan, Ailao Shan and Day Nui Con Voi massifs

NASA Astrophysics Data System (ADS)

Liu, Junlai; Tang, Yuan; Tran, My-Dung; Cao, Shuyun; Zhao, Li; Zhang, Zhaochong; Zhao, Zhidan; Chen, Wen

2012-03-01

The structural geology, timing of shearing, and tectonic implications of the ASRR shear zone, one of the most striking lineaments in Southeast Asia, have been the topics of extensive studies over the past few decades. The Xuelong Shan (XLS), Diancang Shan (DCS), Ailao Shan (ALS) and Day Nui Con Voi (DNCV) metamorphic massifs along the shear zone have preserved important information on its structural and tectonic evolution. Our field structural analysis, detailed microstructural and fabric analysis, as well as the quartz, sillimanite and garnet fabric studies of the sheared rocks from the massifs demonstrate the dominant roles of three deformation episodes during Cenozoic tectonic evolution in the shear zone. Among the contrasting structural and microstructural associations in the shear zone, D2 structures, which were formed at the brittle to ductile transition during large-scale left-lateral shearing in the second deformation episode, predominate over the structural styles of the other two deformation episodes. Discrete micro-shear zones with intensive grain size reduction compose the characteristic structural style of D2 deformation. In addition, several types of folds (early shearing folds, F21, and late-shearing folds, F22) were formed in the sheared rocks, including discrete to distributed mylonitic foliation, stretching lineation and shear fabrics (e.g., mica fish, domino structures, as well as sigma and delta fabrics). A sequence of microstructures from syn-kinematic magmatic flow, high-temperature solid-state deformation, to brittle-ductile shearing is well-preserved in the syn-kinematic leucocratic intrusions. Deformation structures from the first episode (D1) are characterized by F1 folds and distributed foliations (S1) in rocks due to pure shearing at high temperatures. They are preserved in weakly sheared (D2) rocks along the eastern margin of the ALS belt or in certain low-strain tectonic enclaves within the shear zone. Furthermore, semi-brittle deformation structures, such as hot striae and discrete retrogression zones, are attributed to normal-slip shearing in the third deformation episode (D3), which was probably locally active, along the eastern flank of the DCS range, for example. There are four quartz c-axis fabric patterns in the mylonitic rocks, including type A point maxima, type B Y point maxima with crossed girdles superimposition, type C quadrant maxima, as well as type D point and quadrant maxima combination. They are consistent with microscopic observations of microstructures of high-temperature pure shearing, low-temperature simple shearing and their superimposition. Integrated microstructural analysis and fabric thermometer studies provide information on both high temperature (up to 750 °C) and dominant low-temperature (300-600 °C) deformations of quartz grains in different rock types. Sillimanite and garnet fabrics, especially the latter, were primarily formed at the peak metamorphism during high-temperature pure shearing. The above structural, microstructural and fabric associations were generated in the tectonic framework of the Indian-Eurasian collision. The low-temperature microstructures and fabrics are attributed to left-lateral shearing along the ASRR shear zone from 27 to 21 Ma during the southeastward extrusion of the Indochina block, which postdated high-temperature deformation at the peak metamorphism during the collision.

Healthy aging profile in octogenarians in Brazil.

PubMed

Campos, Ana Cristina Viana; Ferreira, Efigênia Ferreira E; Vargas, Andréa Maria Duarte; Gonçalves, Lúcia Hisako Takase

2016-08-29

to identify the healthy aging profile in octogenarians in Brazil. this population-based epidemiological study was conducted using household interviews of 335 octogenarians in a Brazilian municipality. The decision-tree model was used to assess the healthy aging profile in relation to the socioeconomic characteristics evaluated at baseline. All of the tests used a p-value < 0.05. the majority of the 335 participating older adults were women (62.1%), were aged between 80 and 84 years (50.4%), were widowed (53.4%), were illiterate (59.1%), had a monthly income of less than one minimum wage (59.1%), were retired (85.7%), lived with their spouse (63.8%), did not have a caregiver (60.3%), had two or more children (82.7%), and had two or more grandchildren (78.8%). The results indicate three age groups with a healthier aging profile: older adults aged 80 to 84 years (55.6%), older adults aged 85 years and older who are married (64.9%), and older adults aged 85 and older who do not have a partner or a caregiver (54.2%). the healthy aging profile of octogenarians can be explained by age group, marital status, and the presence of a caregiver. identificar o perfil do envelhecimento saudável de idosos brasileiros octogenários. estudo epidemiológico de base populacional, conduzido por meio de entrevista domiciliar em um município brasileiro, num recorte com 335 idosos octogenários. O modelo de árvore de decisão foi utilizado para analisar o perfil de envelhecimento saudável em relação às características socioeconômicas avaliadas na linha base. Todos os testes consideraram o valor p<0,05. entre os 335 idosos que participaram deste estudo, a maioria era do sexo feminino (62,1%), idade entre 80 e 84 anos (50,4%), viúvo (53,4%), analfabeto (59,1%), com renda mensal inferior a um salário-mínimo (59,1%); eram aposentados (85,7%), morando com cônjuge (63,8%), sem cuidador (60,3%), com dois ou mais filhos (82,7%) e dois ou mais netos (78,8%). Os resultados indicam três grupos com perfil de envelhecimento mais saudável: idosos com 80-84 anos (55,6%), idosos com 85 anos e mais, casados (64,9%) e idosos com 85 anos e mais, sem companheiro e também sem cuidador (54,2%). o perfil de envelhecimento saudável de octogenários pôde ser explicado pela faixa etária, estado civil e presença de cuidador. identificar el perfil de envejecimiento saludable de octogenarios brasileños. estudio epidemiológico de base poblacional que se llevó a cabo por medio de entrevistas domiciliarias en un municipio brasileño con una muestra de 335 octogenarios. Se utilizó un modelo de árbol de decisiones para analizar el perfil de envejecimiento saludable en relación a las características socioeconómicas evaluadas al inicio del estudio. Todos las pruebas consideraron un valor de p<0,05. entre los 335 adultos mayores participantes, la mayoría eran mujeres (62,1%), edades comprendidas entre 80 y 84 años (50,4%), viudos (53,4%), analfabetos (59,1 %), con ingreso mensual inferior del salario mínimo (59,1%), jubilados (85,7%), viviendo con el cónyuge (63,8%), sin cuidador (60,3%), con dos o más hijos (82,7%), y dos o más nietos (78,8%). Los resultados indican tres grupos de edad con perfil de envejecimiento más saludable: adultos mayores de 80-84 años (55,6%), adultos mayores con 85 años o más y casados (64,9%), y adultos mayores con 85 años o más sin pareja y ni cuidador (54,2%). el perfil de envejecimiento saludable de octogenarios se puede explicar por el grupo etario, el estado civil y la presencia de un cuidador.

Comparación de las predicciones de cosmologías alternativas al modelo estándar con datos del fondo cósmico de radiación

NASA Astrophysics Data System (ADS)

Piccirilli, M. P.; Landau, S. J.; León, G.

2016-08-01

The cosmic microwave background radiation is one of the most powerful tools to study the early Universe and its evolution, providing also a method to test different cosmological scenarios. We consider alternative inflationary models where the emergence of the seeds of cosmic structure from a perfect isotropic and homogeneous universe can be explained by the self-induced collapse of the inflaton wave function. Some of these alternative models may result indistinguishable from the standard model, while others require to be compared with observational data through statistical analysis. In this article we show results concerning the first Planck release, the Atacama Cosmology Telescope, the South Pole Telescope, the WMAP and Sloan Digital Sky Survey datasets, reaching good agreement between data and theoretical predictions. For future works, we aim to achieve better limits in the cosmological parameters using the last Planck release.

Diseno de una Actividad de Aprendizaje Basada en la Argumentacion Dialogica en un curso Virtual de Biotecnologia y su Incidencia en el Desarrollo de Competencias Cientificas

NASA Astrophysics Data System (ADS)

Ortiz Benavides, Fedra Lorena

El proposito de la investigacion fue evaluar la efectividad de una actividad de aprendizaje basado en la argumentacion dialogica en linea y su incidencia en el desarrollo de competencias cientificas. Se fundamenta en la teoria del aprendizaje socio cultural de Vigotsky (1984), los principios del diseno instruccional de la cognicion situada por Hung y Der-Thang (2001) y como estrategia se aplico la argumentacion dialogica utilizando el Modelo Argumentativo de Toulmin MAT (1984). El diseno experimental comparo dos grupos de estudiantes A y B en el curso virtual de Biotecnologia. El grupo A (experimental) desarrollo la discusion a partir de la estrategia disenada para este estudio y el grupo B (control) realizo la discusion desde las actividades tradicionales. El desarrollo de la competencia argumentativa se valoro con el instrumento de evaluacion para argumentacion dialogica en linea propuesta por Clark y Sampson (2008). La evaluacion de las competencias cientificas se realizo a partir de una postprueba. Los datos fueron analizados con pruebas estadisticas no parametricas. Los resultados de la investigacion, indicaron diferencias significativas en el nivel de la competencia argumental en el grupo experimental en comparacion al grupo control. Igualmente se demostro que existe una relacion positiva entre el nivel de desarrollo de la competencia argumentativa y el nivel de desarrollo de las competencias cientificas.

Biblioteca Virtual de Salud Enfermería Regional: Trayectoria de Construcción, Fuentes de Información, Estrategias y Próximos Pasos.

PubMed Central

Lana, Francisco C. F.; Malvárez, Silvina

2012-01-01

Resumen La BVS Enfermeria constituye un nuevo paradigma en enfermería una vez que o modelo representa una expansión de la cooperación técnica y ha como objetivos centrales promover la ampliación del acceso la información sobre enfermería la través del acceso universal equitativo y construir un patrimonio informacional en enfermería, ayudando la mejorar la formación y práctica de enfermería a actuar con compromiso ético-social en el área de educación, investigación y atención a la salud. Como resultado del proceso de sensibilización, verifica-se la construcción de Bibliotecas Virtuales de Enfermería en varios países (Brasil, Argentina, Bolívia y Uruguay). La expectativa es que las BVS’s nacionais convergen a un gran portal que se está construyendo en una colaboración con BIREME/OPS/OMS, de la Asesoría Regional de Enfermería de la OPS-Washington y de Ministerio de Salud del Brasil, así como instituciones líderes en la producción del conocimiento en enfermería Iberoamérica. PMID:24199093

Apoyo a Estudios Geodinamicos con GPS en Guatemala

NASA Astrophysics Data System (ADS)

Robles, V. R.

2013-05-01

El Instituto Geografico Nacional de Guatemala implemento 17 estaciones GNSS en el año 2009, como un proyecto de credito mixto de donacion de equipamiento del Gobierno de Suiza, el cual, este equipamiento de estaciones CORS GNSS es un sistema de recepción y transmisión de datos crudos GPS RInex que utiliza la tecnologia Spider Web de Leica, asi mismo este sistema esta sirviendo para el espablecimiento de un marco geodesico nacional de coordenadas geodesicas oficiales, el cual se calculan u obtienen las velocidades en tiempos temporales programados de las 17 Estaciones CORS. La infraestructura del marco geodesico de Guatemala esta sirviendo de base para las aplicaciones de estudios geodinamicos como el monitoreo de del desplazamiento de las placas tectonicas por medio de un estudio que se inicio en el año de 1999, llamado medicion con GPS el sistema de Fallas de los rios Polochic Motagua de Guatemala, tambien para un estudio que se implemento para deformación de corteza terrestre local en un Volcan Activo de Guatemala llamado Pacaya. Para el estudio de medicion con GPS en el sistema de falla de los Rios del polochic Motagua se implementaron 16 puntos para medir con GPS de dos frecuencias en el año de 1999, el cual, tres puntos son estaciones geodesicas CORS IGS llamados GUAT, ELEN y HUEH, despues en el año de 2003 se hizo otra medicion en un total de 20 puntos, que permitió calcular las velocidades de desplazamieinto de los puntos en mención, usando como referencia el modelo NUVEL 1A de DeMets de la placa de Norteamerica. Este estudio fue en cooperación internacional por la universidad de Nice de Francia y el IGNde Francia. Para el estudio del monitoreo con GPS del volcan activo de Guatemala, se implementaron cuatro puntos al rededor del volcan, el cual, se realizan cuatro mediciones al año, que permiten determinar axialmente la distancias entre los puntos, y rebisar estadisticamente cual es el comportamiento de las distancias en funcion del tiempo, si existen diferencias graduales crecientes o decrecientes, que nos da un indicativo del desplazamiento de la corteza terrestre al rededor del volcan.

Study of the Local Horizon. (Spanish Title: Estudio del Horizonte Local.) Estudo do Horizonte Local

NASA Astrophysics Data System (ADS)

Ros, Rosa M.

2009-12-01

The study of the horizon is fundamental to easy the first observations of the students at any education center. A simple model, to be developed in each center, allows to easy the study and comprehension of the rudiments of astronomy. The constructed model is presented in turn as a simple equatorial clock, other models (horizontal and vertical) may be constructed starting from it. El estudio del horizonte es fundamental para poder facilitar las primeras observaciones de los alumnos en un centro educativo. Un simple modelo, que debe realizarse para cada centro, nos permite facilitar el estudio y la comprensión de los primeros rudimentos astronómicos. El modelo construido se presenta a su vez como un sencillo modelo de reloj ecuatorial y a partir de él se pueden construir otros modelos (horizontal y vertical). O estudo do horizonte é fundamental para facilitar as primeiras observações dos alunos num centro educativo. Um modelo simples, que deve ser feito para cada centro, permite facilitar o estudo e a compreensão dos primeiros rudimentos astronômicos. O modelo construído apresenta-se, por sua vez, como um modelo simples de relógio equatorial e a partir dele pode-se construir outros modelos (horizontal e vertical)

Factors associated with young adults' knowledge regarding family history of Stroke.

PubMed

Lima, Maria Jose Melo Ramos; Moreira, Thereza Maria Magalhães; Florêncio, Raquel Sampaio; Braga, Predro

2016-11-21

to analyze the factors associated with young adults' knowledge regarding family history of stroke. an analytical transversal study, with 579 young adults from state schools, with collection of sociodemographic, clinical and risk factor-related variables, analyzed using logistic regression (backward elimination). a statistical association was detected between age, civil status, and classification of arterial blood pressure and abdominal circumference with knowledge of family history of stroke. In the final logistic regression model, a statistical association was observed between knowledge regarding family history of stroke and the civil status of having a partner (ORa=1.61[1.07-2.42]; p=0.023), abdominal circumference (ORa=0.98[0.96-0.99]; p=0.012) and normal arterial blood pressure (ORa=2.56[1.19-5.52]; p=0.016). an association was observed between socioeconomic factors and risk factors for stroke and knowledge of family history of stroke, suggesting the need for health education or even educational programs on this topic for the clientele in question. analisar os fatores associados ao conhecimento dos adultos jovens sobre histórico familiar de Acidente Vascular Cerebral (AVC). estudo transversal analítico, com 579 adultos jovens de escolas públicas, com coleta de variáveis sociodemográficas, clínicas e de fatores de risco em formulário, analisados utilizando-se regressão logística (backward elimination). detectou-se associação estatística de idade, situação conjugal, classificação da pressão arterial e circunferência abdominal com conhecimento do histórico familiar de AVC. No modelo final de regressão logística, observou-se associação estatística do conhecimento sobre histórico familiar de AVC com situação conjugal com companheiro (ORa=1,61[1,07-2,42]; p=0,023), circunferência abdominal (ORa=0,98[0,96-0,99]; p=0,012) e pressão arterial normal (ORa=2,56[1,19-5,52]; p=0,016). foi constatada associação de fatores socioeconômicos e de risco para AVC com o conhecimento do histórico familiar de AVC, sugerindo a necessidade de educação em saúde ou mesmo de programas educacionais sobre o tema junto à clientela em estudo. analizar los factores asociados al conocimiento de los adultos jóvenes sobre el histórico familiar de Accidente Vascular Cerebral (AVC). estudio transversal analítico en 579 adultos jóvenes de escuelas públicas, con recolección de variables sociodemográficas, clínicas y de factores de riesgo en formulario, los datos fueron analizados utilizando la regresión logística (backward elimination). se detectó asociación estadística de edad, situación conyugal, clasificación de la presión arterial y circunferencia abdominal con el conocimiento del histórico familiar de AVC. En el modelo final de regresión logística, se observó una asociación estadística del conocimiento sobre el histórico familiar de AVC con: situación conyugal con compañero (ORa=1,61[1,07-2,42] p=0,023); circunferencia abdominal (ORa=0,98[0,96-0,99] p=0,012); y presión arterial normal (ORa=2,56[1,19-5,52] p=0,016). fue constatada asociación de factores socioeconómicos y de riesgo para AVC con el conocimiento del histórico familiar de AVC; se sugiere la necesidad de realizar acciones de educación en salud o inclusive de preparar programas educacionales sobre el tema para la población estudiada.

Medición de los parámetros cosmológicos q0, ΩM, y ΩΛ, usando supernovas de Tipo Ia distantes

NASA Astrophysics Data System (ADS)

Clocchiatti, A.; High-Z Sne Search Team

Las supernovas de tipo Ia son una herramienta de gran precisión para la medición de distancias de interés cosmológico. Los métodos recientes de calibración de su luminosidad intrínseca, que hacen uso de la forma de las curvas de luz en varios colores y permiten diferenciar entre supernovas distantes, intrínsecamente débiles, u oscurecidas por extinción, reducen la dispersión del método que las asume de magnitud absoluta constante de 0.50 mag a 0.15 mag, e incrementa el valor de la constante de Hubble de ~55 km s-1 Mpc-1, a 65 km s-1 Mpc-1. A partir de la calibración de las supernovas cercanas, con redshifts menores que 0.1, se pueden obtener distancias precisas a supernovas que explotan a alto redshift. Hemos aplicado estos métodos a 16 supernovas con 0.16 < Z < 0.97, encontrando que sus distancias son, en promedio, entre 10% y 13% (dependiendo del método empleado) mayores que las que uno esperaría en un universo con poca masa (Ω = 0.2), sin una constante cosmológica. Todos los métodos de ajuste de curvas de luz, y selección de subgrupos de la muestra de supernovas observadas, favorecen consistentemente modelos del universo que se expanden eternamente y que tienen una constante cosmológica positiva (ΩΛ > 0), y una aceleración de la expansión al presente (q0 < 0). Hay distintas fuentes de posibles errores sistemáticos que merecen ser analizadas, entre ellas: evolución de la metalicidad y estrellas progenitoras, extinción, bias en la elección de la muestra, amplificación por gravitational lensing, y contaminación de la muestra. Ninguno de estos efectos alcanza para reconciliar los datos con ΩΛ = 0, o q0 > 0.

Toward Advanced Nursing Practice along with People-Centered Care Partnership Model for Sustainable Universal Health Coverage and Universal Access to Health.

PubMed

Kamei, Tomoko; Takahashi, Keiko; Omori, Junko; Arimori, Naoko; Hishinuma, Michiko; Asahara, Kiyomi; Shimpuku, Yoko; Ohashi, Kumiko; Tashiro, Junko

2017-01-30

this study developed a people-centered care (PCC) partnership model for the aging society to address the challenges of social changes affecting people's health and the new role of advanced practice nurses to sustain universal health coverage. a people-centered care partnership model was developed on the basis of qualitative meta-synthesis of the literature and assessment of 14 related projects. The ongoing projects resulted in individual and social transformation by improving community health literacy and behaviors using people-centered care and enhancing partnership between healthcare providers and community members through advanced practice nurses. people-centered care starts when community members and healthcare providers foreground health and social issues among community members and families. This model tackles these issues, creating new values concerning health and forming a social system that improves quality of life and social support to sustain universal health care through the process of building partnership with communities. a PCC partnership model addresses the challenges of social changes affecting general health and the new role of advanced practice nurses in sustaining UHC. o estudo desenvolveu um modelo de parceria de cuidados centrados nas pessoas (CCP) para uma sociedade que está envelhecendo, com o fim de enfrentar os desafios das mudanças sociais que afetam a saúde das pessoas e o novo papel da prática avançada de enfermagem para sustentar a cobertura universal de saúde. um modelo de parceria de cuidados centrados nas pessoas foi desenvolvido com base na meta-síntese qualitativa da literatura e a avaliação de 14 projetos relacionados. Os projetos em curso resultaram na transformação individual e social, melhorando a alfabetização de saúde da comunidade e comportamentos que usam o cuidado centrado nas pessoas e aumentando a parceria entre os profissionais de saúde e membros da comunidade por meio da prática avançada de enfermagem. o cuidado centrado nas pessoas começa quando os membros da comunidade e os profissionais de saúde colocam em primeiro plano as questões sociais entre os membros da comunidade e das famílias. Esse modelo aborda essas questões, a criação de novos valores relativos à saúde e forma um sistema social que melhora a qualidade de vida e dá apoio social para sustentar o sistema de saúde universal por meio da construção de parcerias com as comunidades. um modelo de parceria CCP aborda os desafios das mudanças sociais que afetam a saúde geral e o novo papel das enfermeiras de prática avançada em sustentar a UHC. este estudio desarrolló un modelo de alianza para el cuidado centrado en las personas (CCP) para una sociedad envejecida, que haga frente a los retos de los cambios sociales que afectan a la salud de las personas y el nuevo papel de las enfermeras de práctica avanzada para apoyar la cobertura universal de salud. un modelo de alianza para el cuidado centrado en las personas fue desarrollado sobre la base de la meta-síntesis cualitativa de la literatura y la evaluación de 14 proyectos relacionados. Los proyectos en curso dieron lugar a la transformación individual y social mejorando la "alfabetización sanitaria" de la comunidad y los comportamientos, utilizando los cuidados centrados en las personas y aumentando la colaboración entre los profesionales sanitarios y miembros de la comunidad a través de las enfermeras de práctica avanzada. el cuidado centrado en las personas comienza cuando los miembros de la comunidad y los profesionales sanitarios ponen en primer plano a la salud y las cuestiones sociales entre los miembros de la comunidad y las familias. Este modelo aborda estas cuestiones, creando nuevos valores relativos a la salud y formando un sistema social que mejora la calidad de vida y el apoyo social para hacer sostenible la atención sanitaria universal a través del proceso de construcción de alianzas con las comunidades. un modelo de alianza para CCP responde a los desafíos de los cambios sociales que afectan a la salud en general y al nuevo papel de las enfermeras de práctica avanzada en el sostenimiento de la Cobertura Universal en Salud (CUS).

Conceptuaciones de los estudiantes de las facultades de educacion y ciencias naturales de la Universidad de Puerto Rico, recinto de Rio Piedras, acerca de la ciencia y la pseudociencia

NASA Astrophysics Data System (ADS)

Reyes Medina, Hector A.

Esta investigacion describe las conceptuaciones de los estudiantes de tercer ano o mas a nivel de bachillerato de los programas de Educacion en Ciencia y Ciencias Naturales de la Universidad de Puerto Rico, Recinto de Rio Piedras, acerca de lo establecido en la literatura para distinguir el conocimiento cientifico de las creencias pseudocientificas. Este estudio se guio por un diseno tipo encuesta transversal que permitio conocer de manera consistente las conceptuaciones de los estudiantes encuestados acerca de la Ciencia y la Pseudociencia. Ademas, permitio desarrollar inferencias estadisticas relacionadas a la poblacion de estudio, sus conceptuaciones y su inclinacion teorica en torno al Realismo y al Racionalismo cientifico moderados. El instrumento utilizado fue el Cuestionario acerca de las concepciones de la ciencia y la pseudocienca en estudiantes universitarios, Reyes (2015). Este cuestionario fue validado mediante la recopilacion de diversas fuentes de evidencias, entre estas se encuentran las evidencias basadas en el contenido, el proceso de respuesta, la estructura interna y de constructo. Tambien, se calculo el Alfa de Crombach para la escala total y para cada componente y se realizo un analisis de factores que demostro la presencia de seis componentes claramente definidos de acuerdo a lo esperado sobre las caracteristicas originales del instrumento. Las estadisticas utilizadas fueron descriptivas. Participaron 302 alumnos, de las facultades de educacion y ciencias naturales. Se encontro que las conceptuaciones de los estudiantes de ambas facultades se inclinan en un 66.2% a favor con lo establecido en el modelo teorico en torno al Realismo y al Racionalismo cientifico moderados. Sin embargo, aun hay un 33.8% de los estudiantes de ambas facultades que poseen conceptuaciones distintas al modelo teorico propuesto.

PubMed

Abrutzky, Rosana; Torres, Fernando Adrián; Ossorio, María Fabiana; Ferrero, Fernando

2018-04-11

Objetivo: evaluar el impacto de los contaminantes atmosféricos y el clima en el número de consultas al departamento de emergencias de un hospital pediátrico en Buenos Aires, Argentina. Material y métodos: estudio ecológico utilizando análisis de series temporales con modelos aditivos generalizados (GAM) para el período 2012-2014, analizando cantidad diaria de consultas en función de tres contaminantes del aire: monóxido de carbono (CO), dióxido de nitrógeno (NO2) y material particulado de diámetro menor a 10 micrones (PM10), temperatura diaria, humedad relativa, dirección y velocidad del viento y lluvia, controlando por día de la semana y tendencia de largo plazo. Resultados: las consultas en invierno (286 diarias) fueron significativamente mayores que en las demás estaciones (p<0.0001). La variación en el nivel de contaminación del aire no mostró correlación significativa y consistente con las consultas. La temperatura, humedad relativa, lluvia y viento no resultaron significativas en ninguno de los rezagos analizados. Conclusiones: en esta población y considerando las consultas de emergencia, la contaminación del aire no afecta significativamente el resultado en salud, pero sí lo hacen las epidemias estacionales. Estudios sobre otras variables de salud son necesarios para establecer el impacto de la contaminación del aire sobre la salud infantil en Buenos Aires.

Autoreporte de exposición a publicidad y promoción de tabaco en una cohorte de fumadores mexicanos: Antes y durante la publicación de la Ley General para el Control del tabaco en 2008

PubMed Central

Hernández, Rosaura Pérez; Thrasher, James F.; Bolaños, Rosibel Rodríguez; Gutiérrez, Inti Barrientos; Hernández, Norma A Ibañez

2015-01-01

Resumen Objetivo Determinar en población fumadora el nivel de exposición a la mercadotecnia por parte de la Industria Tabacalera (IT), a través de diferentes métodos de promocionar sus productos de tabaco, antes y durante la publicación de la Ley General para el Control del Tabaco (LGCT) en 2008. Material y métodos Estudio de cohorte en fumadores adultos (n=941 pre-LGCT y n=1051 post-LGCT) de cuatro ciudades mexicanas. Se realizaron análisis multivariados mediante modelos de ecuaciones de estimación generalizada (GEE). Resultados Se incremento el autoreporte de recepción de muestras gratis de cigarros (3.7% a 8.1%), ropa o artículos con marcas o logos (3.6% a 6.4%), haber visto información sobre eventos especiales (1.9% a 4.7%), y bares, antros y discos para mayores de edad (21.4% a 28%). Se observaron decrementos de publicidad en exteriores (54.7% a 47.2%). Conclusión Es necesaria una política integral con prohibiciones totales de la publicidad y promoción de los productos de tabaco que integre mayor vigilancia y sanciones para lograr la disminución y prevención del consumo de tabaco. PMID:22689158

Análisis del futuro marco de referencia internacional

NASA Astrophysics Data System (ADS)

Cionco, G. R.; Arias, E. F.

La técnica de interferometría de muy larga línea de base (VLBI) se aplica hoy a la astrometría para el cálculo de posiciones precisas de radiofuentes extragalácticas. Por tratarse de objetos lejanos, sus movimientos propios aparentes pueden considerarse nulos; esta propiedad hace que los catálogos de radiofuentes extragalácticas VLBI constituyan la mejor materialización de un sistema de referencia celeste inercial definido cinemáticamente. La Unión Astronómica Internacional (IAU) recomendó la adopción de un nuevo sistema de referencia celeste internacional materializado por las coordenadas ecuatoriales de objetos extragalácticos observados con le técnica VLBI. Para superar la precisión astrométrica actual es necesaria una mejora en la modelización de aquellos fenómenos que pueden introducir desviaciones sistemáticas en el marco de referencia celeste. El objetivo de este trabajo es poner de manifiesto las sistematicidades presentes en los distintos marcos de referencia elaborados con el próposito de materializar el nuevo sistema de referencia celeste de la IAU. Para la comparación de los distintos marcos de referencia se propone un modelo de tres rotaciones diferenciales más un término lineal que procura absorber los efectos sistemáticos presentes en las coordenadas. Se analiza igualmente la estabilidad de la solución cuando se utilizan distintos conjuntos de objetos de definición.

El nuevo panorama de la Dinámica Galáctica

NASA Astrophysics Data System (ADS)

Pivovaroff, Michael James

En general, la tendencia imperante en Dinámica Galáctica ha sido considerar que los movimientos estelares son básicamente regulares y que el caos no tiene mayor relevancia en los sistemas estelares. Sin embargo, en el último lustro se vienen acumulando pruebas de la importancia del movimiento caótico en ciertos sistemas estelares que existen en la naturaleza. Por una parte, sobre todo el grupo de David Merritt, lo ha mostrado en los casos de galaxias elípticas con concentraciones centrales de materia; por otra parte, en nuestro propio grupo, lo hemos mostrado para el caso de los satélites galácticos. Las consecuencias de estos hallazgos son tanto de tipo técnico, por la necesidad de construir modelos que contengan órbitas caóticas, como astrofísico, por los efectos del caos sobre la estacionariedad y evolución de los sistemas estelares en los que se presenta.

Newtonian Version of the Variable Mass Theory of Gravity

NASA Astrophysics Data System (ADS)

Carvalho, J. C.; Lima, J. A. S.

1990-11-01

RESUMEN. Se presenta una versi6n Newtoniana de los modelos cosmol6gicos espacialmente e isotr6picos con masa variable. La influencia de la variaci6n de masa en la evoluci6n de la funci6n de escala est establecida para el caso de un Universo lieno de polvo bajo Ia suposici6n de que esta variaci6n es un efecto estrictamente cosmol6jico. Se muestra que el hiperb6lico, parab6lico 0 el#ptico dcl movimiento de puede ser modificado a lo larjo de la expansi6n. ABSTRACT. This paper presents a Newtonian version of the spatially homojeneous and isotropic cosmolojical models with variable mass. The influence of the mass variation on the evolution of the scale function is established for the case of a dust-filled Universe under the assumption that this variation is a strict cosmolojical effect. It is shown that the hyperbolic, parabolic or elliptic character of the fluid motion can be modified alonj the expansion. Keq : COSMOLOGY

[Not Available].

PubMed

Molina Garrido, María José

2016-06-03

Cada vez es mayor el número de ancianos con diagnóstico de cáncer que acuden a las consultas de Oncología Médica. El proceso del envejecimiento y la gran variabilidad existente en la población geriátrica implican que, para hacer un abordaje adecuado del paciente, se deba considerar la edad fisiológica del anciano, y no su edad biológica. Para ello, es preciso hacer una evaluación somera, específica e individualizada a cada uno de los ancianos con diagnóstico de cáncer que acudan a nuestra consulta. La valoración geriátrica integral (VGI) es la herramienta clave que permite evaluarlos de forma adecuada, e incluso orienta la toma de decisiones "personalizada" en los ancianos con diagnóstico de cáncer. Dado que la VGI consume mucho tiempo en la consulta diaria, se están desarrollando distintas herramientas de cribado que permitan acortar la atención al paciente, al seleccionar aquellos ancianos que deban someterse a una VGI y aquellos en los que esta no sea necesaria. Se han publicado distintos modelos de VGI en la Oncogeriatría y se han desarrollado distintas herramientas de cribado de fragilidad; los más conocidos son el cuestionario Vulnerable Elders Survey-13 (VES-13) y el cuestionario G-8. En este artículo se hace una revisión acerca de la evidencia científica existente en cuanto a la atención y valoración del anciano oncológico, así como los distintos parámetros de los que se disponen para la toma de decisiones definitiva. Dichos datos reflejan el papel de la Oncogeriatría como la vía para ofrecer una atención global óptima a este grupo poblacional.

Efectos combinados de la ampliación de la atención primaria de salud y de las transferencias condicionadas de dinero en efectivo sobre la mortalidad infantil en Brasil, 1998–2010*

PubMed Central

Guanais, Frederico C.

2015-01-01

Objetivos. Examiné los efectos combinados del acceso a la atención primaria mediante el Programa de Salud Familiar (PSF) y las transferencias condicionadas de dinero en efectivo del Programa Bolsa Familia (PBF) sobre la mortalidad infantil posneonatal (MIPN) en Brasil. Métodos. Empleé un análisis ecológico longitudinal usando datos en panel de 4 583 municipios brasileños de 1998 al 2010, con 54 253 observaciones en total. Estimé modelos de regresión de efectos fijos por mínimos cuadrados ordinarios, con la tasa de MIPN como la variable dependiente y el PSF, el PBF y sus interacciones como las principales variables independientes de interés. Resultados. La asociación de una mayor cobertura del PSF con una menor tasa de MIPN se volvió más fuerte conforme aumentaba la cobertura del PBF. En los promedios de todas las demás variables, cuando la cobertura de PBF era 25%, la MIPN predicha fue 5,24 (intervalo de confianza [IC] de 95% = 4,95, 5,53) para una cobertura del PSF de 0%, y de 3,54 (IC de 95% = 2,77, 4,31) para una cobertura del PSF de 100%. Cuando la cobertura del PBF era de 60%, la MIPN predicha fue 4,65 (IC de 95% = 4,36, 4,94) para una cobertura del PSF de 0%, y de 1,38 (IC de 95% = 0,88, 1,89) para una cobertura del PSF de 100%. Conclusiones. El efecto del PSF depende de la ampliación del PBF. Para las poblaciones empobrecidas y subatendidas, la combinación de intervenciones tanto del lado de la oferta como del lado de la demanda podría ser necesaria para mejorar los resultados en salud.

Evolución de estrellas de Helio

NASA Astrophysics Data System (ADS)

Panei, J. A.; Benvenuto, O. G.; Althaus, L. G.

Podríamos identificar a las estrellas de helio con estrellas Wolf-Rayet (WR) que han perdido su envoltura rica en hidrógeno ya sea porque las mismas pertenecen a sistemas binarios o a través de fuertes vientos estelares. Las WR representan una etapa evolucionaria normal de las estrellas masivas, cuya pérdida de masa es >= 3 × 10-5Msolar/yr y la cual es sufrida por la estrella en un tiempo de escala mucho menor que el tiempo en que se produce la quema del He. Esto garantiza la ``homogeneidad'' de las estrellas de helio para nuestros modelos. Este tipo de estrellas serían posibles progenitores de SN tipo Ib y Ic. Aquí presentamos un estudio sobre la evolución de estrellas de helio a partir de la secuencia principal de helio, pasando por el flash de carbono, hasta agotarlo en la región central; como así también la dependencia con la variable masa y con la pérdida de la misma para distintos tipos de masas. Para tal fin hemos utilizado un código de evolución estelar completo que realiza todas las reacciones de Fowler en forma simultánea. También se han tenido en cuenta los procesos de mezcla convectiva, los principales mecanismos de emisión de neutrinos y los efectos de la pérdida de masa. Las opacidades utilizadas fueron las de Rogers & Iglesias (1992). Debido a la pérdida de masa en este tipo de estrellas, hemos encontrado que los perfiles convectivos, la composición química, las condiciones centrales de temperatura y presión, luminosidad y temperatura efectiva dependen en forma esencial de la velocidad de pérdida de masa adoptada, lo que tendría profundas implicaciones en la evolución posterior de estos objetos.

Analyzing the Potential for Unmanned Aerial Systems (UAS) Photogrammetry in Estimating Surface Deformations at a Geothermal Fiel

NASA Astrophysics Data System (ADS)

Pai, H.; Burnett, J.; Sladek, C.; Wing, M.; Feigl, K. L.; Selker, J. S.; Tyler, S.; Team, P.

2016-12-01

UAS systems equipped with a variety of spectral imaging devices are increasingly incorporated in spatial environmental assessments of continental surfaces (e.g., digital elevation maps, vegetative coverage classifications, surface temperatures). This presented work performed by the UAS team at the Center for Transformative Environmental Monitoring Programs (AirCTEMPS) examines the potential to measure small (sub-cm) deformation from a geothermal injection experiment at Brady's geothermal field in western Nevada (USA). Areal mapping of the 700 x 270 m area of interest was conducted with a nadir pointing Sony A5100 digital camera onboard an autopiloted quadcopter. A total of 16 ground control points were installed using a TopCon GR3 GPS receiver. Two such mapping campaigns were conducted with one before and one after an anticipated surface deformation event. A digital elevation map (DEM) for each time period was created from over 1500 images having 80% overlap/sidelap by using structure from motion (SfM) via Agisoft Photoscan software. The resulting DEM resolution was 8 mm/pixel with residual aerial triangulation errors was < 5 mm. We present preliminary results from an optimized workflow which achieved errors and average differential DEM heights between campaigns at the cm-scale which is broader than the maximum expected deformation. Despite the disconnect between error and deformation severity, this study presents a unique application of sub-cm UAS-based DEMs and further distinguishes itself by comparing results to concurrent Interferometric Synthetic Radar (InSAR). The intent of our study and presentation of results is to streamline, cross-validate, and share methods to encourage further adoption of UAS imagery into the standard toolkit for environmental surface sensing across spatial scales.

Análise da aplicação e dos resultados do modelo OPM3® para a área da saúde

PubMed Central

Augusto dos Santos, Luis; de Fátima Marin, Heimar

2015-01-01

Esta pesquisa procurou analisar se um modelo de questionário criado por uma comunidade internacional de gerenciamento de projetos e se é aplicavél a organizações voltadas a área de saúde. O modelo OPM3® (Organizational Project Management Maturity Model) foi criado para que organizações de qualquer área ou porte pudessem identificar a presença, ou ausência, de boas práticas de gerenciamento. O objetivo da aplicação desse modelo é avaliar sempre a organização e não o entrevistado. No presente artigo, são apresentados os resultados da aplicação desse modelo em uma organização que possuía produtos e serviços de tecnologia da informação aplicados à área de saúde. Este estudo verificou que o modelo é aplicável de forma rápida e que a organização analisada possuía um número expressivo de boas práticas. PMID:26924862

Cerebrospinal Fluid Pressure: Revisiting Factors Influencing Optic Nerve Head Biomechanics

PubMed Central

Hua, Yi; Voorhees, Andrew P.; Sigal, Ian A.

2018-01-01

Purpose To model the sensitivity of the optic nerve head (ONH) biomechanical environment to acute variations in IOP, cerebrospinal fluid pressure (CSFP), and central retinal artery blood pressure (BP). Methods We extended a previously published numerical model of the ONH to include 24 factors representing tissue anatomy and mechanical properties, all three pressures, and constraints on the optic nerve (CON). A total of 8340 models were studied to predict factor influences on 98 responses in a two-step process: a fractional factorial screening analysis to identify the 16 most influential factors, followed by a response surface methodology to predict factor effects in detail. Results The six most influential factors were, in order: IOP, CON, moduli of the sclera, lamina cribrosa (LC) and dura, and CSFP. IOP and CSFP affected different aspects of ONH biomechanics. The strongest influence of CSFP, more than twice that of IOP, was on the rotation of the peripapillary sclera. CSFP had similar influence on LC stretch and compression to moduli of sclera and LC. On some ONHs, CSFP caused large retrolamina deformations and subarachnoid expansion. CON had a strong influence on LC displacement. BP overall influence was 633 times smaller than that of IOP. Conclusions Models predict that IOP and CSFP are the top and sixth most influential factors on ONH biomechanics. Different IOP and CSFP effects suggest that translaminar pressure difference may not be a good parameter to predict biomechanics-related glaucomatous neuropathy. CON may drastically affect the responses relating to gross ONH geometry and should be determined experimentally. PMID:29332130

Cannabis-related episodic memory deficits and hippocampal morphological differences in healthy individuals and schizophrenia subjects

PubMed Central

Smith, Matthew J.; Cobia, Derin J.; Reilly, James L.; Gilman, Jodi; Roberts, Andrea G.; Alpert, Kathryn I.; Wang, Lei; Breiter, Hans C.; Csernansky, John G.

2015-01-01

Cannabis use has been associated with episodic memory (EM) impairments and abnormal hippocampus morphology among both healthy individuals and schizophrenia subjects. Considering the hippocampus' role in EM, research is needed to evaluate the relationship between cannabis-related hippocampal morphology and EM among healthy and clinical groups. We examined differences in hippocampus morphology between control and schizophrenia subjects with and without a past (not current) cannabis use disorder (CUD). Subjects group-matched on demographics included 44 healthy controls (CON), 10 subjects with a CUD history (CON-CUD), 28 schizophrenia subjects with no history of substance use disorders (SCZ), and 15 schizophrenia subjects with a CUD history (SCZ-CUD). Large- deformation, high-dimensional brain mapping with MRI produced surface-based representations of the hippocampus that were compared across all four groups and correlated with EM and CUD history. Surface maps of the hippocampus were generated to visualize morphological differences. CON-CUD and SCZ- CUD were characterized by distinct cannabis-related hippocampal shape differences and parametric deficits in EM. Shape differences observed in CON-CUD were associated with poorer EM, while shape differences observed in SCZ-CUD were associated with a longer duration of CUD and shorter duration of CUD abstinence. A past history of CUD may be associated with notable differences in hippocampal morphology and EM impairments among adults with and without schizophrenia. Although the results may be compatible with a causal hypothesis, we must consider that the observed cannabis-related shape differences in the hippocampus could also be explained as biomarkers of a neurobiological susceptibility to poor memory or the effects of cannabis. PMID:25760303

Age Rb/Sr de 1670 M.a. pour les mylonites de l'accident du Sassandra (Côte d'Ivoire) conséquence pour la datation des mouvements fini-éburnéens dans le craton ouest-africain

NASA Astrophysics Data System (ADS)

Caen-Vachette, M.; Tempier, P.; Camil, J.

An eight point Rb/Sr isochron determination on whole rocks yielded an age of 1670 M.a. for the mylonites from the Sassandra couloir of ductile deformation, which extends N-S. A similar age is proposed for the mylonite from a zone of parallel trend stretching NNW-SSE in the Reguibat dome (Mauritania). A correlation is suggested with the Guri fault of the Guayana shield in South America.

Evaluation of probabilistic flow in two unsaturated soils

NASA Astrophysics Data System (ADS)

Boateng, Samuel

2001-11-01

A variably saturated flow model is coupled to a first-order reliability algorithm to simulate unsaturated flow in two soils. The unsaturated soil properties are considered as uncertain variables with means, standard deviations, and marginal probability distributions. Thus, each simulation constitutes an unsaturated probability flow event. Sensitivities of the uncertain variables are estimated for each event. The unsaturated hydraulic properties of a fine-textured soil and a coarse-textured soil are used. The properties are based on the van Genuchten model. The flow domain has a recharge surface, a seepage boundary along the bottom, and a no-flow boundary along the sides. The uncertain variables are saturated water content, residual water content, van Genuchten model parameters alpha (α) and n, and saturated hydraulic conductivity. The objective is to evaluate the significance of each uncertain variable to the probabilistic flow. Under wet conditions, saturated water content and residual water content are the most significant uncertain variables in the sand. For dry conditions in the sand, however, the van Genuchten model parameters α and n are the most significant. Model parameter n and saturated hydraulic conductivity are the most significant for the wet clay loam. Saturated water content is most significant for the dry clay loam. Résumé. Un modèle d'écoulement variable en milieu saturé est couplé à un algorithme d'exactitude de premier ordre pour simuler les écoulements en milieu non saturé dans deux sols. Les propriétés des sols non saturés sont considérés comme des variables incertaines avec des moyennes, des écarts-types et des distributions de probabilité marginale. Ainsi chaque simulation constitue un événement d'écoulement non saturé probable. La sensibilité des variables incertaines est estimée pour chaque événement. Les propriétés hydrauliques non saturées d'un sol à texture fine et d'un sol à texture grossière sont utilisées. Les propriétés sont basées sur le modèle de van Genuchten. Le domaine d'écoulement possède une surface de recharge, une limite de fuite à sa base et des limites sans écoulement sur les côtés. Les variables incertaines sont la teneur en eau à saturation, la teneur en eau résiduelle, les paramètres alpha (α) et n du modèle de van Genuchten et la conductivité hydraulique à saturation. L'objectif est d'évaluer la signification de chacune des variables incertaines dans l'écoulement probabiliste. Dans des conditions humides, la teneur en eau à saturation et la teneur en eau résiduelle sont les variables incertaines les plus significatives dans le sable. Toutefois, dans des conditions sèches dans le sable, les paramètres α et n du modèle de van Genuchten sont les plus significatifs. Le paramètre n du modèle et la conductivité hydraulique à saturation sont les plus significatifs pour un sol argileux humide. La teneur en eau à saturation est très significative pour le sol argileux sec. Resumen. Se ha acoplado un modelo de flujo de saturación variable con un algoritmo de fiabilidad de primer orden con el fin de simular el flujo no saturado en dos tipos de suelos. Se ha tratado las propiedades del suelo no saturado como variables inciertas, a las que se asigna las medias, desviaciones estándar y distribuciones de probabilidad marginal correspondientes. Así, cada simulación constituye un evento probabilístico de flujo no saturado y la sensibilidad de las variables inciertas es estimada para cada evento. Se ha utilizado las propiedades de la conductividad hidráulica no saturada de dos suelos con dos tipos de textura - fina y gruesa - mediante el modelo de van Genuchten. El dominio de flujo está delimitado por una superficie de recarga, base de goteo y contornos laterales de flujo nulo. Las variables inciertas son el contenido de agua residual, el de saturación, los parámetros del modelo de van Genuchten (α y n) y la conductividad hidráulica saturada. El objetivo era evaluar la contribución de cada variable incierta al flujo probabilístico. Para arenas, las variables inciertas más importantes, en condiciones de humedad, son el contenido de agua residual y el de saturación en ausencia de humedad, lo son ambos parámetros del modelo de van Genuchten. Para margas arcillosas, las variables más significativas en condiciones húmedas son el parámetro n y la conductividad hidráulica saturada; en condiciones secas, el contenido de agua en saturación.

Construction and validation of nursing diagnoses for people in palliative care.

PubMed

Silva, Rudval Souza da; Pereira, Álvaro; Nóbrega, Maria Miriam Lima da; Mussi, Fernanda Carneiro

2017-08-03

to construct and validate nursing diagnoses for people in palliative care based on the Dignity-Conserving Care Model and the International Classification for Nursing Practice. a two-stage methodological study: 1) construction of the database of clinically and culturally relevant terms for the nursing care for people in palliative care and 2) construction of nursing diagnoses from the database of terms, based on the guidelines of the International Council of Nurses. the 262 terms validated constituted a database of terms from which 56 nursing diagnoses were developed. Of these, 33 were validated by a group of 26 experts, and classified in the three categories of the Dignity-Conserving Care Model: illness-related concerns (21); dignity-conserving repertoire (9); and social dignity inventory (3). of the 33 validated diagnoses, 18 of them could be included in the update of the Catalog of the International Classification for Nursing Practice - palliative care for a dignified death. The study contributes to support the clinical reasoning and decision making of the nurse. construir e validar diagnósticos de enfermagem para pessoas em cuidados paliativos, fundamentados no Modelo de Cuidados para Preservação da Dignidade e na Classificação Internacional para a Prática de Enfermagem. estudo metodológico operacionalizado em duas etapas: 1) construção do banco de termos relevantes, clínica e culturalmente, para a assistência de enfermagem à pessoa em cuidados paliativos e 2) construção de diagnósticos de enfermagem a partir do banco de termos, com base nas diretrizes do Conselho Internacional de Enfermeiros. os 262 termos validados constituíram um banco de termos a partir do qual foram desenvolvidos 56 diagnósticos de enfermagem. Desses, 33 foram validados por um grupo de 26 peritos, e classificados nas três categorias do Modelo de Cuidados para Preservação da Dignidade: preocupações relacionadas com a doença (21); repertório de conservação da dignidade (9); inventário da dignidade social (3). dos 33 diagnósticos validados, 18 deles poderão ser incluídos na atualização do Catálogo da Classificação Internacional para a Prática de Enfermagem - cuidados paliativos para uma morte digna. O estudo contribui para subsidiar o enfermeiro no raciocínio clínico e na tomada de decisão. construir y validar diagnósticos de enfermería para personas en cuidados paliativos, fundamentados en el Modelo de Cuidados para Preservación de la Dignidad y en la Clasificación Internacional para la Práctica de Enfermería. estudio metodológico operacionalizado en dos etapas: 1) construcción del banco de términos relevantes, clínicamente y culturalmente, para la asistencia de enfermería a la persona en cuidados paliativos y 2) construcción de diagnósticos de enfermería a partir del banco de términos, con base en las directrices del Consejo Internacional de Enfermeros. los 262 términos validados constituyeron un banco de términos a partir del cual fueron desarrollados 56 diagnósticos de enfermería. De esos, 33 fueron validados por un grupo de 26 peritos, y clasificados en las tres categorías del Modelo de Cuidados para Preservación de la Dignidad: preocupaciones relacionadas con la enfermedad (21); repertorio de conservación de la dignidad (9); inventario de la dignidad social (3). de los 33 diagnósticos validados, 18 de ellos podrán ser incluidos en la actualización del Catálogo de la Clasificación Internacional para la Práctica de Enfermería - cuidados paliativos para una muerte digna. El estudio contribuye para auxiliar al enfermero en el raciocinio clínico y en la toma de decisiones.

Cannabis-related episodic memory deficits and hippocampal morphological differences in healthy individuals and schizophrenia subjects.

PubMed

Smith, Matthew J; Cobia, Derin J; Reilly, James L; Gilman, Jodi M; Roberts, Andrea G; Alpert, Kathryn I; Wang, Lei; Breiter, Hans C; Csernansky, John G

2015-09-01

Cannabis use has been associated with episodic memory (EM) impairments and abnormal hippocampus morphology among both healthy individuals and schizophrenia subjects. Considering the hippocampus' role in EM, research is needed to evaluate the relationship between cannabis-related hippocampal morphology and EM among healthy and clinical groups. We examined differences in hippocampus morphology between control and schizophrenia subjects with and without a past (not current) cannabis use disorder (CUD). Subjects group-matched on demographics included 44 healthy controls (CON), 10 subjects with a CUD history (CON-CUD), 28 schizophrenia subjects with no history of substance use disorders (SCZ), and 15 schizophrenia subjects with a CUD history (SCZ-CUD). Large-deformation, high-dimensional brain mapping with MRI produced surface-based representations of the hippocampus that were compared across all four groups and correlated with EM and CUD history. Surface maps of the hippocampus were generated to visualize morphological differences. CON-CUD and SCZ-CUD were characterized by distinct cannabis-related hippocampal shape differences and parametric deficits in EM performance. Shape differences observed in CON-CUD were associated with poorer EM performance, while shape differences observed in SCZ-CUD were associated with a longer duration of CUD and shorter duration of CUD remission. A past history of CUD may be associated with notable differences in hippocampal morphology and EM impairments among adults with and without schizophrenia. Although the results may be compatible with a causal hypothesis, we must consider that the observed cannabis-related shape differences in the hippocampus could also be explained as biomarkers of a neurobiological susceptibility to poor memory or the effects of cannabis. © 2015 Wiley Periodicals, Inc.

Observaciones de la corona solar interior con un coronógrafo de espejo

NASA Astrophysics Data System (ADS)

Stenborg, G.; Schwenn, R.; Francile, C.; Rovira, M.

El plasma de la corona solar es un buen indicador de las líneas de fuerza del campo magnético. Por lo tanto, el análisis de estructuras coronales cuasiestacionarias en la corona da importante información sobre el campo magnético y la actividad asociada. Se trata de poner límites a los modelos teóricos existentes mediante el estudio de distintas estructuras en la corona interior. En agosto de 1997 comenzó a operar el coronógrafo solar (MICA) en El Leoncito como parte del Observatorio Solar Alemán-Argentino. Desde su instalación obtiene imágenes de la corona solar (1.05 a 2.0 radios solares) en 2 líneas espectrales correspondientes a la emisión de Fe XIV y Fe X. El instrumento puede obtener imágenes cada minuto por lo que es ideal para estudiar procesos rápidos. Presentamos observaciones recientes que muestran la capacidad del coronógrafo así como la evolución de algunos eventos dinámicos observados por MICA.

Diseño de un programa basado en la promoción del desarrollo positivo en la infancia para la prevención temprana de la violencia en Colombia.

PubMed

Hernández Holguín, Dora M; Páez Zapata, Esteban; Múnera Restrepo, Laura M; Duque Ramírez, Luis F

2017-03-01

Aunque algunos informes identifiquen a Colombia como ejemplo de un país que ha logrado revertir los niveles crecientes de violencia, estos siguen siendo altos. Por este motivo se han convocado acciones de promoción de la convivencia y prevención de la violencia, a las cuales responde el programa que presentamos en este artículo. Este programa está basado en la perspectiva contextual-evolutiva del modelo ecológico y en la educación para la salud, tendiente al cuidado de sí en los padres o cuidadores, y al ejercicio de una crianza, centrada en los derechos de los niños, el desarrollo infantil y la promoción de la salud mental, con el fin de promover el desarrollo saludable y prevenir comportamientos agresivos en los niños; éste es presentado como una alternativa de orientación psicosocial para el fortalecimiento de estrategias y programas dirigidos a la primera infancia.

Fundamentals of soft robot locomotion

PubMed Central

2017-01-01

Soft robotics and its related technologies enable robot abilities in several robotics domains including, but not exclusively related to, manipulation, manufacturing, human–robot interaction and locomotion. Although field applications have emerged for soft manipulation and human–robot interaction, mobile soft robots appear to remain in the research stage, involving the somehow conflictual goals of having a deformable body and exerting forces on the environment to achieve locomotion. This paper aims to provide a reference guide for researchers approaching mobile soft robotics, to describe the underlying principles of soft robot locomotion with its pros and cons, and to envisage applications and further developments for mobile soft robotics. PMID:28539483

Fundamentals of soft robot locomotion.

PubMed

Calisti, M; Picardi, G; Laschi, C

2017-05-01

Soft robotics and its related technologies enable robot abilities in several robotics domains including, but not exclusively related to, manipulation, manufacturing, human-robot interaction and locomotion. Although field applications have emerged for soft manipulation and human-robot interaction, mobile soft robots appear to remain in the research stage, involving the somehow conflictual goals of having a deformable body and exerting forces on the environment to achieve locomotion. This paper aims to provide a reference guide for researchers approaching mobile soft robotics, to describe the underlying principles of soft robot locomotion with its pros and cons, and to envisage applications and further developments for mobile soft robotics. © 2017 The Author(s).

Construyendo modelos confiables de estrellas rías

NASA Astrophysics Data System (ADS)

Mauas, P. J.; Falchi, A.

Se estudian las aproximaciones que se realizan usualmente al calcular modelos de estrellas frías (redistribución completa para la lí nea Lyman-α, despreciar el ``line-blanketing", suponer los metales en LTE), y cómo influyen en los distintos observables. Asimismo, se evalúa cuál es la información que cada observable nos da sobre la atmósfera de la estrella, y cuáles son las incertidumbres de cada modelo.

Dynamic and Structural Performances of a New Sailcraft Concept for Interplanetary Missions.

PubMed

Peloni, Alessandro; Barbera, Daniele; Laurenzi, Susanna; Circi, Christian

2015-01-01

Typical square solar-sail design is characterised by a central hub with four-quadrant sails, conferring to the spacecraft the classical X-configuration. One of the critical aspects related to this architecture is due to the large deformations of both membrane and booms, which leads to a reduction of the performance of the sailcraft in terms of thrust efficiency. As a consequence, stiffer sail architecture would be desirable, taking into account that the rigidity of the system strongly affects the orbital dynamics. In this paper, we propose a new solar-sail architecture, which is more rigid than the classical X-configuration. Among the main pros and cons that the proposed configuration presents, this paper aims to show the general concept, investigating the performances from the perspectives of both structural response and attitude control. Membrane deformations, structural offset, and sail vibration frequencies are determined through finite element method, adopting a variable pretensioning scheme. In order to evaluate the manoeuvring performances of this new solar-sail concept, a 35-degree manoeuvre is studied using a feedforward and feedback controller.

Dynamic and Structural Performances of a New Sailcraft Concept for Interplanetary Missions

PubMed Central

Peloni, Alessandro; Barbera, Daniele; Laurenzi, Susanna; Circi, Christian

2015-01-01

Typical square solar-sail design is characterised by a central hub with four-quadrant sails, conferring to the spacecraft the classical X-configuration. One of the critical aspects related to this architecture is due to the large deformations of both membrane and booms, which leads to a reduction of the performance of the sailcraft in terms of thrust efficiency. As a consequence, stiffer sail architecture would be desirable, taking into account that the rigidity of the system strongly affects the orbital dynamics. In this paper, we propose a new solar-sail architecture, which is more rigid than the classical X-configuration. Among the main pros and cons that the proposed configuration presents, this paper aims to show the general concept, investigating the performances from the perspectives of both structural response and attitude control. Membrane deformations, structural offset, and sail vibration frequencies are determined through finite element method, adopting a variable pretensioning scheme. In order to evaluate the manoeuvring performances of this new solar-sail concept, a 35-degree manoeuvre is studied using a feedforward and feedback controller. PMID:26273697

Association between poor clinical prognosis and sleep duration among breast cancer patients.

PubMed

Mansano-Schlosser, Thalyta Cristina; Ceolim, Maria Filomena

2017-06-05

to investigate the association between clinical progression and the quality and duration of sleep in women with breast cancer. longitudinal study, with 114 participants, conducted in a hospital in Brazil. The instruments used were: questionnaire for sociodemographic and clinical characterization, Pittsburgh Sleep Quality Index; Beck Depression Inventory and Herth Hope Scale. Data were analyzed through descriptive statistics and survival analyses (outcome: poor clinical progression), using the Kaplan-Meier curve, Log-rank test and Cox proportional model. a higher probability of poor clinical progression was verified in women with sleep durations of less than six hours or nine hours and over (p=.0173). the results suggest the importance of further studies that seek to verify whether the quantitative management of sleep disorders would have an impact on the progression of breast cancer. Women should be encouraged to report sleep problems to nurses. mensurar a associação entre evolução clínica e qualidade e duração do sono em mulheres com câncer de mama. estudo longitudinal, com 114 participantes, realizado em um hospital do Brasil. Os instrumentos utilizados foram: questionário para caracterização sociodemográfica e clínica, Índice de Qualidade do Sono de Pittsburgh; Inventário de Depressão de Beck e Escala de Esperança de Herth. Os dados foram analisados via análises descritivas e de sobrevivência (resultado: evolução clínica desfavorável), utilizando-se a curva de Kaplan-Meier, o teste log-rank e o modelo proporcional de Cox. verificou-se maior probabilidade de evolução clínica desfavorável em mulheres com duração de sono inferior a seis ou mais de nove horas (p = 0,0173). os resultados sugerem a importância de mais estudos que buscam verificar se a gestão quantitativa dos distúrbios do sono teria um impacto sobre a evolução do câncer de mama. As mulheres devem ser encorajadas a relatar isso espontaneamente aos enfermeiros. medir la asociación entre progresión clínica y calidad y duración del sueño en mujeres con cáncer de mama. estudio longitudinal, con 114 participantes, realizado en un hospital de Brasil. Los instrumentos utilizados fueron: cuestionario para caracterización sociodemográfica y clínica; índice de calidad del sueño de Pittsburgh; Inventario de Depresión de Beck; y Escala de esperanza de Herth. Los datos se analizaron a través de análisis descriptivo y de supervivencia (resultado: evolución clínica desfavorable), utilizando la curva de Kaplan-Meier, la prueba log-rank y el modelo proporcional de Cox. se comprobó una mayor probabilidad de progresión clínica desfavorable en mujeres con duración de sueño inferior a seis horas o más de nueve horas (p = 0,0173). los resultados sugieren la importancia de realizar más estudios que busquen verificar si la gestión cuantitativa de los trastornos del sueño tendría un impacto en la progresión del cáncer de mama. Las mujeres deben ser alentadas a informar esto espontáneamente a las enfermeras.

El aprendizaje significativo en las ciencias al participar en proyectos de investigacion cientifica

NASA Astrophysics Data System (ADS)

Mora Polanco, Miguelena

La ciencia es el eje fundamental a traves del cual se desarrollan las habilidades necesarias para el pensar cientifico que va a la busqueda del conocimiento cientifico. La intencion de este estudio fue indagar en el tema de investigacion cientifica desde el punto de vista de los participantes en los siguientes aspectos relacionados con la experiencia de investigacion cientifica: a) conceptos, b) proceso, c) destrezas y d) disposicion. Tambien se analizaron: a) las perspectivas del metodo cientifico, b) la estrategia de ensenanza, c) la cultura cientifica y d) la exposicion del proyecto investigativo en la Feria Cientifica; como parte del aprendizaje significativo de la ciencias de los participantes. Esta investigacion cualitativa propuso como diseno el estudio de caso. Los aspectos relacionados a la experiencia de participar en proyecto de investigacion cientifica son el fenomeno o caso bajo estudio. En el estudio participaron cinco (5) estudiantes egresados de escuela publica o privada que cursaban hasta el tercer ano de estudios universitarios, conducentes a un bachillerato en educacion secundaria en ciencias o en ciencias naturales. Las tecnicas utilizadas para recopilar los datos fueron: analisis de documentos del DEPR, revision de artefactos y entrevistas profundas. Para el analisis de los datos de las entrevistas se utilizo el modelo de Wolcott (1994). Del analisis de documentos del DEPR se identificaron areas a mejorar en las guias de las cartas circulares con relacion a la investigacion escolar y la feria cientifica. El analisis de los artefactos proveyo evidencia de como los internados, simposios e investigaciones fomentan el que los estudiantes se superen en el aspecto cognitivo, se conviertan en creadores del conocimiento, al hacer suyo los conceptos para poder explicarlos al publico. De las entrevistas los participantes manifestaron que la experiencia de investigacion fue una de aprendizaje significativo que los marco para toda la vida y les expandio su curiosidad de modo que lo aplican en su vida. La experiencia los ayudo en el entendimiento y la aplicacion de conceptos, procesos y destrezas relacionados con la ciencia. Finalmente, los participantes proveyeron las estrategias didacticas que desde su perspectiva facilitan la ensenanza-aprendizaje de la ciencia.

La masa de los grandes impactores

NASA Astrophysics Data System (ADS)

Parisi, M. G.; Brunini, A.

Los planetas han sido formados fundamentalmente acretando masa a través de colisiones con planetesimales sólidos. La masa más grande de la distribución de planetesimales y las masas máxima y mínima de los impactores, han sido calculadas usando los valores actuales del período y de la inclinación de los planetas (Lissauer & Safronov 1991; Parisi & Brunini 1996). Recientes investigaciones han mostrado, que las órbitas de los planetas gigantes no han sufrido variaciones con el tiempo, siendo su movimiento regular durante su evolución a partir de la finalización de la etapa de acreción (Laskar 1990, 1994). Por lo tanto, la eccentricidad actual de los planetas gigantes se puede utilizar para imponer una cota máxima a las masas y velocidades orbitales de los grandes impactores. Mediante un simple modelo dinámico, y considerando lo arriba mencionado, obtenemos la cota superior para la masa del planetesimal más grande que impactó a cada planeta gigante al final de su etapa de acreción. El resultado más importante de este trabajo es la estimación de la masa máxima permitida para impactar a Júpiter, la cúal es ~ 1.136 × 10 -1, siendo en el caso de Neptuno ~ 3.99 × 10 -2 (expresada en unidades de la masa final de cada planeta). Además, fue posible obtener la velocidad orbital máxima permitida para los impactores como una función de su masa, para cada planeta. Las cotas obtenidas para la masa y velocidad de los impactores de Saturno y Urano (en unidades de la masa y velocidad final de cada planeta respectivamente) son casi las mismas que las obtenidas para Júpiter debido a que estos tres planetas poseen similar eccentricidad actual. Nuestros resultados están en buen acuerdo con los obtenidos por Lissauer & Safronov (1991). Estas cotas podrían ser utilizadas para obtener la distribución de planetesimales en el Sistema Solar primitivo.

Land subsidence caused by groundwater exploitation in Suzhou City, China

NASA Astrophysics Data System (ADS)

Chen, Chongxi; Pei, Shunping; Jiao, Jiu Jimmy

2002-09-01

Suzhou City, located at the lower reaches of the Yangtze River in southeastern Jiangsu Province, is one of the few cities in China which suffer from severe ground settlement. A research project was carried out to investigate this problem. Geological and hydrogeological studies show that there is a multi-layered aquifer system with three distinct, soft mud layers of marine and lagoonal origins. An examination of historical records of groundwater extraction, water levels, and ground settlement shows that the ground subsidence is associated with the continuously increasing groundwater extraction in the deep, confined aquifer. It is believed that the consolidation of the soft mud layers, especially the third layer which is thick and close to the main pumped aquifer, contributes to the ground settlement. A three-dimensional finite difference numerical model representing the multi-layered aquifer system was developed to study the ground settlement in response to groundwater extraction. By calibrating the model with both the measured groundwater level and ground settlement, the aquifer parameters were estimated. The model outputs fit reasonably well with the observed results, which indicates that the numerical model can reproduce the dynamic processes of both groundwater flow and soil consolidation. The hydraulic conductivity of the third mud layer near the center of the ground settlement has been reduced by over 30% in the last 14 years. The gradual deterioration in the hydraulic conductivity of the mud may have significant adverse effect on the sustainable groundwater resource of the deep confined aquifer, since the recharge from the shallow aquifers through the mud layer is the only source of water to the deep aquifer. An analysis of the spatial distributions of groundwater drawdown and ground settlement shows that the area with maximum drawdown is not necessarily the area with maximum ground settlement due to the occurrence of the soft mud layer. A simple reallocation in pumping rates on the basis of the spatial distribution of the thick mud layer could significantly reduce the ground settlement. Résumé. La ville de Suzhou, située dans la basse vallée du fleuve Yangtsé dans le sud-est de la province de Jiangsu, est l'une des rares villes de Chine qui souffrent cruellement de tassements du sol. Un projet de recherche a été mené pour étudier ce problème. Des études géologiques et hydrogéologiques montrent qu'il existe un système aquifère multicouche constitué de trois niveaux distincts de limons non consolidés d'origine marine et lagunaire. Un examen des historiques des prélèvements d'eau souterraine, des niveaux de nappe et des tassements de sol montrent que la subsidence du sol est associée à des prélèvements continuellement croissants d'eau souterraine dans l'aquifère captif profond. On pense que le compactage des couches limoneuses non consolidées, en particulier de la troisième couche qui est épaisse et proche du principal aquifère pompé, contribue aux tassements du sol. Un modèle numérique aux différences finies en trois dimensions, représentant l'aquifère multicouche, a été réalisé pour étudier les tassements du sol en réponse aux prélèvements d'eau souterraine. Les paramètres de l'aquifère ont été estimés par calibration du modèle au moyen à la fois des niveaux piézométriques et des tassements du sol. Les résultats de la simulation s'ajustent convenablement aux résultats observés, ce qui indique que le modèle numérique peut reproduire les processus dynamiques aussi bien des écoulements souterrains que de compactage du sol. La conductivité hydraulique de la troisième couche de limon non consolidé au voisinage du centre du tassement de sol a été réduit de plus de 30% au cours des 14 dernières années. La dégradation progressive de la conductivité hydraulique du limon peut avoir un effet significatif néfaste sur la pérennité de la ressource en eau souterraine dans l'aquifère captif profond, puisque la recharge à partir des aquifères superficiels au travers de la couche de limon est la seule alimentation de l'aquifère profond. Une analyse des distributions spatiales de l'abaissement du niveau piézométrique et des tassements du sol montre que la région soumise à l'abaissement maximal de piézométrie n'est pas nécessairement celle des tassements maximaux du sol liés à la présence de la couche de limon non consolidé. Une simple révision des débits de pompage basée sur la distribution spatiale de la couche de limon épaisse peut réduire significativement les tassements du sol. Resumen. La ciudad de Suzhou, situada en el tramo inferior del Río Yangtze, al sudeste de la provincia de Jiangsu, es una de las pocas ciudades chinas que padece problemas serios de subsidencia. Esto ha motivado la realización de un proyecto de investigación en la zona. Estudios geológicos e hidrogeológicos apuntan a un modelo de acuífero multicapa, con tres niveles distintos de lodos blandos de orígenes marino y lacustre. Examinando los registros históricos de extracciones de agua subterránea, así como de nivel piezométrico y de subsidencia, se observa que ésta se halla asociada al bombeo cada vez mayor del acuífero confinado profundo. La hipótesis es que las capas de lodos blandos se van consolidando, si bien la que más contribuye a ello es la tercera, potente y próxima al acuífero más explotado. Se ha realizado un modelo numérico tridimensional en diferencias finitas que representa el sistema acuífero multicapa, con lo que se puede estudiar el efecto de la extracción de agua subterránea en la subsidencia. Calibrando el modelo con niveles piezométricos medidos y con datos de subsidencia, se ha podido estimar los parámetros del acuífero. Los resultados del modelo ajustan de forma razonable con los datos medidos, por lo que el modelo numérico es capaz de reproducir los procesos dinámicos de flujo de aguas subterráneas y consolidación del terreno. La conductividad hidráulica de la tercera capa de lodo cerca del centro de asentamiento se ha reducido en más del 30% durante los últimos 14 años. El deterioro gradual de la conductividad hidráulica del lodo puede tener efectos adversos notables en la sustentabilidad de los recursos de agua subterránea del acuífero confinado profundo, ya que se recarga exclusivamente de acuíferos más someros a través de la capa de lodo. El análisis de la distribución espacial de descenso del nivel piezométrico y de subsidencia muestra que el área de extracción máxima no coincide necesariamente con la de máxima subsidencia, debido a la existencia de la capa de lodos blandos. Una mera redistribución de los caudales de bombeo en función de las propiedades espaciales de la gruesa capa de lodos podría reducir drásticamente los problemas de subsidencia.

Sterile insect technique: A model for dose optimisation for improved sterile insect quality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, A.; Mehta, K.

The sterile insect technique (SIT) is an environment-friendly pest control technique with application in the area-wide integrated control of key pests, including the suppression or elimination of introduced populations and the exclusion of new introductions. Reproductive sterility is normally induced by ionizing radiation, a convenient and consistent method that maintains a reasonable degree of competitiveness in the released insects. The cost and effectiveness of a control program integrating the SIT depend on the balance between sterility and competitiveness, but it appears that current operational programs with an SIT component are not achieving an appropriate balance. In this paper we discussmore » optimization of the sterilization process and present a simple model and procedure for determining the optimum dose. (author) [Spanish] La tecnica de insecto esteril (TIE) es una tecnologia de control de plagas favorable para el medio ambiente con una aplicacion de un control integrado de plagas claves para toda la area, incluyendo la supresion o eliminacion de poblaciones introducidas y la exclusion de nuevas introducciones. La esterilidad reproductiva es normalmente inducida por radiacion ionizada, un metodo conveniente y consistente que mantiene un grado razonable para la capacidad de competencia en insectos liberados. El costo y la eficacia de un programa de control que incluye TIE dependen en tener un balance entre la esterilidad y la capacidad para competir, pero parece que los programas operacionales corrientes con TIS como un componente no estan logrando el tener un balance apropiado. En esta publicacion, nosotros discutimos la optimizacion del proceso de esterilizacion y presentamos un modelo y procedimiento sencillos para determinar la dosis optima. (author)« less

The conceptualization model problem—surprise

NASA Astrophysics Data System (ADS)

Bredehoeft, John

2005-03-01

The foundation of model analysis is the conceptual model. Surprise is defined as new data that renders the prevailing conceptual model invalid; as defined here it represents a paradigm shift. Limited empirical data indicate that surprises occur in 20-30% of model analyses. These data suggest that groundwater analysts have difficulty selecting the appropriate conceptual model. There is no ready remedy to the conceptual model problem other than (1) to collect as much data as is feasible, using all applicable methods—a complementary data collection methodology can lead to new information that changes the prevailing conceptual model, and (2) for the analyst to remain open to the fact that the conceptual model can change dramatically as more information is collected. In the final analysis, the hydrogeologist makes a subjective decision on the appropriate conceptual model. The conceptualization problem does not render models unusable. The problem introduces an uncertainty that often is not widely recognized. Conceptual model uncertainty is exacerbated in making long-term predictions of system performance. C'est le modèle conceptuel qui se trouve à base d'une analyse sur un modèle. On considère comme une surprise lorsque le modèle est invalidé par des données nouvelles; dans les termes définis ici la surprise est équivalente à un change de paradigme. Des données empiriques limitées indiquent que les surprises apparaissent dans 20 à 30% des analyses effectuées sur les modèles. Ces données suggèrent que l'analyse des eaux souterraines présente des difficultés lorsqu'il s'agit de choisir le modèle conceptuel approprié. Il n'existe pas un autre remède au problème du modèle conceptuel que: (1) rassembler autant des données que possible en utilisant toutes les méthodes applicables—la méthode des données complémentaires peut conduire aux nouvelles informations qui vont changer le modèle conceptuel, et (2) l'analyste doit rester ouvert au fait que le modèle conceptuel peut bien changer lorsque des nouvelles informations apparaissent. Dans l'analyse finale le hydrogéologue prend une décision subjective sur le modèle conceptuel approprié. Le problème du le modèle conceptuel ne doit pas rendre le modèle inutilisable. Ce problème introduit une incertitude qui n'est pas toujours reconnue. Les incertitudes du modèle conceptuel deviennent plus importantes dans les cases de prévisions à long terme dans l'analyse de performance. La base para hacer un análisis de un modelo es el modelo conceptual. Se define aquí la sorpresa como los datos nuevos que convierten en incoherente al modelo conceptual previamente aceptado; tal como se define aquí esto representa un cambio de paradigma. Los datos empíricos limitados indican que estas sorpresas suceden entre un 20 a un 30% de los análisis de modelos. Esto sugiere que los analistas de modelos de agua subterránea tienen dificultades al seleccionar el modelo conceptual apropiado. No hayotra solución disponible a este problema del modelo conceptual diferente de: (1) Recolectar tanta información como sea posible, mediante la utilización de todos los métodos aplicables, lo cual puede resultar en que esta nueva información ayude a cambiar el modelo conceptual vigente, y (2) Que el analista de modelos se mantenga siempre abierto al hecho de que un modelo conceptual puede cambiar de manera total, en la medida en que se colecte mas información. En el análisis final el hidrogeólogo toma una decisión subjetiva en cuanto al modelo conceptual apropiado. El problema de la conceptualización no produce modelos inútiles. El problema presenta una incertidumbre, la cual a menudo no es tenida en cuentade manera adecuada. Esta incertidumbre en los modelos conceptuales se aumenta, cuando se hacen predicciones a largo plazo del comportamiento de un sistema dado.

The Practice of Research of a Basic Education Teacher Involving Mental Models of the Phases of the Moon and Eclipses. (Spanish Title: La Práctica de Investigación de un Maestro de Educación BÁsica con El Uso de los Modelos Mentales de Las Fases de la Luna Y Eclipses.) A Prática de Pesquisa de um Professor do Ensino Fundamental Envolvendo Modelos Mentais de Fases da Lua e Eclipses

NASA Astrophysics Data System (ADS)

Pessôa Queiroz, Glória; Jubitipan Borges de Sousa, Carlos; Auxiliadora Delgado Machado, Maria

2009-12-01

The inclusion of basic education teachers in the survey domain is a controversial issue and fully debated in the academy. The opportunity for a collective work that incorporated school teachers from a public school to a university's group of physics teaching at university allowed us to glimpse the redefinition of the function of a science teacher (a coauthor of this paper) by himself, such that now he includes research on the knowledge construction by students in his teacher practice. The formation of inter-institutional groups for action planning and research in these areas has proved productive for the task of knowledge construction to support educational processes in school, while the university enriches its collection of experiences critically validated, and can consider the results in teachers initial and continued education. The active participation of the teacher in a research group at the university led him to reflect on the possible didactical ways to be described, analyzed and communicated to other teachers. The construction of a pedagogy that took into account the mental models of students on the basic topics of astronomy, and the changes developed resulting from the lessons taught, led to far-reaching consequences on the pedagogy adopted by the teacher, who incorporates now a new vision of science and alternative forms to dialogue with students, essential components for a researcher in Science Education. La inclusión de los maestros de la escuela básica en el universo de la investigación es polémica y está en amplio debate en el mundo académico. La oportunidad de trabajo colectivo de los maestros de una escuela pública en Río de Janeiro con un grupo universitario de enseñanza de la física nos ha permitido vislumbrar la redefinición de la función de un maestro de ciencias (uno de los coautores de este documento) por él mismo, ahora para incluir la investigación sobre la construcción del conocimiento por los alumnos en su práctica como docente. La formación de grupos interinstitucionales para la planificación de la acción y la investigación ha resultado productiva para el trabajo de construcción de conocimiento de apoyo a los procesos educativos en la escuela, mientras que la universidad enriquece su colección de experiencias validadas, considerando los resultados de la educación inicial y continua de maestros. La participación activa del maestro en un grupo de investigación en la universidad lo llevó a reflexiones sobre los posibles caminos didácticos que pueden ser descriptos, analizados y comunicados a los demás docentes. La construcción de una pedagogía propia, que tuvo en cuenta los modelos mentales de los estudiantes sobre los temas básicos de astronomía, y los cambios desarrollados a partir de las lecciones que enseñó, trajeron consecuencias de largo alcance sobre la pedagogía adoptada por el maestro, que ahora incorpora una nueva visión de la ciencia y formas alternativas al diálogo con los estudiantes, los componentes esenciales para un investigador en Educaciónen Ciencias. A inclusão do professor da escola básica no universo da pesquisa é questão controvertida e em pleno debate no meio acadêmico. A oportunidade de trabalho coletivo que incorporou professores de uma escola municipal no Rio de Janeiro a um grupo de ensino de Física da universidade nos possibilitou vislumbrar a ressignificação da função de um professor de Ciências (co-autor deste trabalho) por ele próprio, agora passando a incluir a pesquisa sobre a construção de conhecimento pelos alunos em sua prática como docente. A formação de grupos interinstitucionais para o planejamento de ações e de pesquisas tem-se mostrado produtiva para um trabalho de construção de conhecimentos a fim de subsidiar processos educativos na escola, ao mesmo tempo em que a universidade enriquece seu acervo de experiências validadas criticamente, podendo considerar seus resultados na formação inicial e continuada de professores. A participação ativa do professor num grupo de pesquisa na universidade o levou à reflexão sobre caminhos didáticos possíveis de serem descritos, analisados e comunicados a outros professores. A construção de uma pedagogia própria, levando em conta os modelos mentais dos alunos sobre temas básicos de Astronomia, e as mudanças promovidas a partir das aulas dadas, trouxeram amplas conseqüências sobre a pedagogia adotada pelo professor. Hoje a prática desse professor incorpora uma nova visão de ciência e formas alternativas de dialogar com os alunos, elementos indispensáveis a um pesquisador em Educação em Ciências.

Inverse modeling of groundwater flow in the semiarid evaporitic closed basin of Los Monegros, Spain

NASA Astrophysics Data System (ADS)

Samper-Calvete, F. J.; García-Vera, M. A.

Only minor attention has been given in the past to the study of closed-basin hydrogeology in evaporitic environments, because these basins usually contain poor-quality groundwater. The motivation for hydrogeological research in the Los Monegros area in northeastern Spain was the approval in 1986 of a large irrigation project in the Ebre River basin. The irrigation of 60,000 ha is planned, partly in an evaporitic closed basin containing playa lakes. The project has given rise to environmental concerns. The evaluation of the hydrologic impacts of irrigation requires quantifying properly the hydrogeology of the area. With the available information, a conceptual hydrogeological model was formulated that identifies two main aquifers connected through a leaky aquitard. On the basis of the conceptual model, a numerical model was calibrated under steady-state conditions using the method of maximum-likelihood automatic parameter estimation (Carrera and Neuman, 1986a). The calibrated model reproduces the measured hydraulic heads fairly well and is consistent with independent information on groundwater discharge. By the solution of the inverse problem, reliable parameter estimates were obtained. It is concluded that anisotropy plays a major role in some parts of the lower aquifer. The geometric average of model conductivity is almost two orders of magnitude larger than the average conductivity derived from small-scale field tests. This scale effect in hydraulic conductivity is consistent with the findings of Neuman (1994) and Sánchez-Vila et al. (1996). Résumé Dans le passé, on s'est peu intéresséà l'hydrogéologie des bassins fermés en milieu évaporitique, parce que ces bassins possèdent en général de l'eau souterraine de qualité médiocre. L'intérêt porté aux recherches hydrogéologiques dans la région de Los Monegros, dans le nord-est de l'Espagne est dûà l'approbation en 1986 d'un vaste projet d'irrigation dans le bassin de l'Ebre. L'irrigation de 60000 ha a été programmée, en partie dans un bassin évaporitique fermé où existent des lacs de playa. Le projet a fait émergé des préoccupations environnementales. L'évaluation des impacts hydrologiques de l'irrigation implique de quantifier correctement l'hydrogéologie de cette région. A partir des informations disponibles, un modèle hydrogéologique conceptuel a étéétabli il identifie deux aquifères principaux interconnectés par drainance au travers d'un imperméable. Un modèle numérique, établi sur la base de ce modèle conceptuel, a été calibré en conditions de régime permanent, en utilisant la méthode d'estimation automatique du maximum de vraisemblance des paramètres (Carrera and Neuman, 1986a). Le modèle calibré reproduit correctement la piézométrie mesurée et est en accord avec les informations concernant l'écoulement des nappes. La résolution du problème inverse a fourni des estimations acceptables des paramètres. On en a conclu que l'anisotropie joue un rôle essentiel dans certaines parties de l'aquifère inférieur. La moyenne géométrique de la conductivité hydraulique est d'environ deux ordres de grandeur plus élevée que la conductivité hydraulique moyenne obtenue par des essais de terrain à l'échelle locale. Cet effet d'échelle sur la conductivité hydraulique est conforme aux résultats obtenus par Neuman (1994) et Sánchez-Vila et al. (1996). Resumen La hidrogeología de zonas endorreicas en zonas evaporíticas ha recibido muy poca atención en el pasado debido fundamentalmente a que en estas zonas las aguas subterráneas tienen una elevada salinidad debido a la alta solubilidad de sus materiales. El interés por la hidrogeología de la zona de Los Monegros en el noreste de España surgió a raiz de la aprobación en 1986 del proyecto de Los Monegros II en la zona central del valle del Ebro que contempla la puesta en regadío de 60,000 ha, algunas de las cuales se encuentran situadas en la zona endorreica de Los Monegros en la que existen toda una serie de lagunas salinas. La implantación del regadío en esta zona puede alterar el régimen hidrológico de las lagunas, provocar problemas de salinización de suelos y aguas y aumentar la salinidad del río Ebro. Con el fin de evaluar estos efectos se construyó un modelo numérico del flujo subterráneo. Con la información disponible se pueden distinguir dos acuíferos que están conectados mediante un acuitardo. El modelo de flujo se calibró en régimen estacionario utilizando el procedimiento de calibración automática de Carrera y Neuman (1986a) basado en el método de la máxima verosimilitud. El modelo finalmente calibrado es capaz de reproducir los niveles piezométricos medidos y es coherente con los resultados de los balances hidrológicos en las lagunas. La conductividad hidráulica media del modelo es superior en casi dos órdenes de magnitud a la media de las conductividades hidráulicas obtenidas en ensayos de campo a escala local. Este efecto de escala en la conductividad hidráulica es coherente con los resultados de Neuman (1994) y Sánchez-Vila et al. (1996) y confirma que dicho efecto también se observa en medios evaporíticos.

Evolução química em galáxias compactas azuis (BCGs)

NASA Astrophysics Data System (ADS)

Lanfranchi, G. A.; Matteucci, F.

2003-08-01

Neste trabalho, a formação estelar e evolução quí mica em galáxias Compactas Azuis (Blue Compact Galaxies - BCGs) foram estudadas através da comparação de previsões de modelos de evolução quí mica a várias razões de abundância quí mica observadas nestas galáxias. Modelos detalhados com recentes dados de nucleossí ntese e que levam em consideração o papel desempenahdo por supernovas de ambos os tipos (II e Ia) na evolução galáctica foram desenvolvidos para as BCGs permitindo seguir a evolução de vários elementos quí micos (H, D, He, C, N, O, Mg, Si, S, Ca, e Fe). O modelo é caracterizado pelas prescrições adotadas para a formação estelar, a qual ocorre em vários surtos de atividade separados por longos perí odos quiescentes. Após ajustar os melhores modelos aos dados observacionais, as previsões destes modelos foram comparadas também a razões de abundância observadas em sistemas Damped Lyman alpha (DLAs) e a origem do N (primária ou secundária) foi discutida. Alguns dos resultados obtidos são: i) as razões de abundância observadas nas BCGs são reproduzidas por modelos com 2 a 7 surtos de formação estelar com eficiência entre n = 0.2-0.9 Gano-1; ii) os baixos valores de N/O observados nestas galáxias são um resultado natural de uma formação estelar em surtos; iii) os modelos para BCGs podem reproduzir os dados dos DLAs, iv) uma quantidade "baixa" de N primário produzido em estrelas de alta massa pode ser uma explicação para os baixos valores de [N/a] observados em DLAs.

Induced seismicity in a salt mine environment evaluated by a coupled continuum-discrete modelling.

NASA Astrophysics Data System (ADS)

Mercerat, E.; Souley, M.; Driad, L.; Bernard, P.

2005-12-01

Within the framework of a research project launched to assess the feasibility of seismic monitoring of underground growing cavities, this specific work focus on two main complementary axis: the validation of seismic monitoring techniques in salt mine environments, and the numerical modelling of deformation and failure mechanisms with their associated acoustic emissions, the induced microseismicity. The underground cavity under monitoring is located at Cerville (Lorraine, France) within a salt layer 180 m deep and it presents a rather regular cylindrical shape of 100 m diameter. Typically, the overburden is characterized by the presence of two competent layers with elasto-brittle behaviour and located 50 m above the salt layer. When the salt exploitation restarts, the cavity will progressively grow causing irreversible damage of the upper layers until its final collapse at a time scale of the order of one year. Numerical modelling of such a complex process requires a large scale model which takes into account both the growing cavity within the salt layer and the mechanical behaviour of the overburden where high deformation and fracturing is expected. To keep the elasto-brittle behaviour of the competent layers where most seismic damage is expected, we use the PFC code (Itasca Cons). To approach the other layers (mainly composed of marls and salt) which present more ductile and/or viscoplastic behaviour, a continuum approach based on the FLAC code (Itasca Cons) is employed. Numerous calibration process were needed to estimate the microproperties used in PFC to reproduce the macroscopic behaviour from laboratory tests performed on samples extracted from the competent layers. As long as the size of the PFC inclusion representing the brittle material is much higher than the core sample sizes, the scale effect of microproperties is examined. The next stage is to perform calculations on the basis of previous macroscopic and microproperties calibration results, and compare them with the observed microseismicity in the rock mass.

Ultrasonically set novel NVC-containing glass-ionomer cements for applications in restorative dentistry.

PubMed

Moshaverinia, Alireza; Ansari, Sahar; Moshaverinia, Maryam; Schricker, Scott R; Chee, Winston W L

2011-09-01

The objective of this study is to investigate the effects of application of ultrasound on the physical properties of a novel NVC (N-vinylcaprolactam)-containing conventional glass-ionomer cement (GIC). Experimental GIC (EXP) samples were made from the acrylic acid (AA)-itaconic acid (IA)-NVC synthesized terpolymer with Fuji IX powder in a 3.6:1 P/L ratio as recommended by the manufacturer. Specimens were mixed and fabricated at room temperature and were conditioned in distilled water at 37°C for 1 day up to 4 week. Ultrasound (US) was applied 20 s after mixing by placing the dental scaler tip on the top of the cement and applying light hand pressure to ensure the tip remained in contact with cement without causing any deformation. Vickers hardness was determined using a microhardness tester. The working and setting times were determined using a Gillmore needle. Water sorption was also investigated. Commercial Fuji IX was used as control for comparison (CON). The data obtained for the EXP GIC set through conventional set (CS) and ultrasonically set (US) were compared with the CON group, using one-way ANOVA and the Tukey multiple range test at α = 0.05. Not only ultrasonic (US) application accelerated the curing process of both EXP cement and CON group but also improved the surface hardness of all the specimens. US set samples showed significantly lower water sorption values (P < 0.05) due to improved acid-base reaction within the GIC matrix and accelerated maturation process. According to the statistical analysis of data, significant increase was observed in the surface hardness properties of CS and US specimens both in EXP samples and the CON groups. It was concluded that it is possible to command set GICs by the application of ultrasound, leading to GICs with enhanced physical and handling properties. US application might be a potential way to broaden the clinical applications of conventional GICs in restorative dentistry for procedures such as class V cavity restorations.

Application of Three-Dimensional Models for the Teaching of Time Zones. (Breton Title: Aplicação de Modelos Tridimensionais Para o Ensino de Fusos Horários.) Aplicación de Modelos Tridimensionales Para la Enseñanza de Husos Horarios

NASA Astrophysics Data System (ADS)

Azevedo Sobreira, Paulo Henrique

2012-07-01

There are several interesting astronomical topics that must be addressed in the High School and Elementary/Middle School in the disciplines of Geography and of Sciences. Among them, the topic of time zones which is one of the most important to understand the correlation of the Earth's rotation and its implications on daily activities of citizens in local scale, regional and global scales which involve problems of time differences. For the teaching of time zones in the lessons of Geography, for example, there are bi-dimensional representations of thematic maps of world time zones, textbooks and atlas. It happens that teachers face some difficulties to permit its students to view three-dimensionally this astronomical phenomenon from the textbooks available in schools. The aim of this paper is to present two proposals with low-cost materials, which allow the preparation of three-dimensional models for the teaching of time zones. Há vários temas astronômicos interessantes que devem ser trabalhados nos Ensinos Médio e Fundamental, nas disciplinas de Geografia e de Ciências. Entre eles, o tema dos fusos horários que é um dos mais importantes para se correlacionar a rotação da Terra e suas implicações nas atividades cotidianas dos cidadãos em escala local, regional e global, que envolvem problemas de diferenças horárias. Para o ensino dos fusos horários nas aulas de Geografia, por exemplo, há representações bidimensionais de mapas temáticos de fusos horários mundiais, nos livros didáticos e nos atlas. Ocorre que os professores enfrentam algumas dificuldades para possibilitar aos seus alunos a visão tridimensional deste fenômeno astronômico, a partir dos materiais didáticos disponíveis nas escolas. O objetivo deste trabalho é apresentar duas propostas para a confecção de materiais de baixo custo, que possibilitem a elaboração de modelos tridimensionais para o ensino dos fusos horários. Hay algunos temas astronómicos interesantes que se deben trabajar en la enseñanza media y básica, en las asignaturas de Geografía y de Ciencias. Entre ellos, el de los husos horarios que es uno de los más importantes para correlacionar la rotación de la Tierra y sus implicaciones en las actividades diarias de los ciudadanos en escala local, regional y global, y en general, cuestiones que implican problemas de las diferencias horarias. Para la enseñanza de los husos horarios en las clases de Geografía, por ejemplo, hay representaciones bidimensionales de los mapas temáticos de husos horarios mundiales, en libros y atlas didácticos. Sin embargo, los profesores se enfrentan con algunas dificultades para hacer posible que sus alumnos tengan una visión tridimensional de este fenómeno astronómico, usando los materiales didácticos disponibles en las escuelas. El objetivo de este trabajo es presentar la construcción de dos propuestas de materiales de bajo costo, que hacen posible la elaboración de modelos tridimensionales para la enseñanza de los husos horarios.

Edades relativas de cúmulos globulares

NASA Astrophysics Data System (ADS)

Miller Bertolami, M.; Forte, J. C.

El trabajo de Rossemberg et al (1999), estudia las edades relativas de cúmulos globulares galácticos mediante el análisis de ciertos parámetros morfológicos de los diagramas color-magnitud de dichos cúmulos. Este trabajo se centra en tres puntos: analizar la consistencia de los resultados obtenidos por Rossemberg et al (1999) al emplear observaciones en el sistema fotométrico de Washington, más precisamente, las magnitudes C y T1 en lugar de las magnitudes V e I utilizadas por dichos autores. De la existencia de colores integrados, metalicidad y edad (relativa) para 21 de los cúmulos utilizados en dicho trabajo, se analiza la consistencia de estos resultados con las dependencias de color integrado como función de la edad y la metalicidad que se desprenden de los modelos teóricos de luz integrada por Worthey (1994), Schulz (2002) y Lee et al (2002). Por último se lleva a cabo una breve comparación de la morfología de los diagramas color-magnitud de los cúmulos globulares y de las isocronas utilizadas, a fin de intentar identificar algunas de las posibles causas de las diferencias observadas en los incisos anteriores.

La inserción en el mercado laboral de los inmigrantes latinos en España y en los Estados Unidos: Diferencias por país de origen y estatus legal

PubMed Central

Connor, Phillip; Massey, Douglas

2013-01-01

Resumen Este artículo compara los resultados económicos entre los inmigrantes latinoamericanos en España y Estados Unidos. Detectamos un efecto de selección por el que la mayoría de los inmigrantes latinoamericanos en España proceden de Sudamérica de un entorno de clases medias, mientras la mayoría de los inmigrantes que van a los Estados Unidos son centroamericanos de clase baja. Este efecto de selección explica las diferencias transnacionales en la probabilidad de empleo, logro ocupacional y salarios obtenidos. A pesar de las diferencias en los orígenes y las características de los latinoamericanos en ambos países, los factores demográficos, humanos y de capital social parecen operar de forma similar en ambos países; y cuando los modelos se estiman separadamente por estatus legal, descubrimos que los efectos se acentúan más entre los inmigrantes irregulares cuando se los compara con los regulares, especialmente en Estados Unidos. PMID:24532857

Modelo semi-empírico de protuberancia solar a partir del diagnóstico de densidades

NASA Astrophysics Data System (ADS)

Cirigliano, D.; Vial, J. C.; Rovira, M.

A partir de la observación del espectro del quintuplete de C III alrededor de 1175 Å, se ha realizado el diagnóstico de la densidad y presión electrónica, basado en el cálculo del cociente de las intensidades observadas. Una vez establecida la densidad electrónica, y con el cálculo de las velocidades Doppler, hemos investigado el flujo de masa en la protuberancia en función de la temperatura. Estableciendo como hipótesis la conservación del número de partículas que ingresan y salen del cuerpo de la protuberancia, se investiga la variación del área de un tubo de flujo semi-empírico en función de la temperatura. A partir de dicho diagnóstico, se examina el comportamiento del radio del tubo magnético en función de la temperatura, los que dan cuenta de la abertura de las líneas de campo magnético que confinan el plasma y de la divergencia del campo magnético en diferentes alturas de la atmósfera solar.

Operational tools and applications of EO satellite data to retrieve surface fluxes in semi-arid countries

NASA Astrophysics Data System (ADS)

Tanguy, Maliko

The objective of the thesis is to develop and evaluate useful tools and applications of Earth Observation (EO) satellite data to estimate surface fluxes in semi-arid countries. In a first part (Chapter 4), we assess the performance of a new parameterisation scheme of ground heat flux (G) to be used in remote sensing (RS) evapotranspiration (ET) estimation methods. The G-parameterisation optimized with AMMA flux data performs well and improves the sensible heat flux (H) and ET retrieved by means of the triangle method (Jiang & Islam, 2001). In a second part (Chapter 5), the triangle method is compared with ET estimated by means of a land surface model (JULES). An attempt is made to calibrate JULES using the triangle method through Monte Carlo simulations, but the two methods supply rather different results, indicating that further intercomparison tasks should be carried out to assess the performance of RS-based algorithms and land surface models in estimating the components of the land surface energy balance. Chapter 6 presents a set of operational examples for retrieving surface fluxes using RS data. The first example is the study of temporal evolution of ET-maps in Western Africa under monsoonal influence. In a second example, we apply the new scheme proposed in Chapter 4 to retrieve and analyse the long term evolution (2000-2009) of the surface energy balance components, G, H and ET at several sites of the Segura Basin (S-E Spain) using MODIS-Terra data (land surface temperature and NDVI). Temporal and spatial distribution of evapotranspiration reveals different controls on ET. (Chapter 6). In the last example, MODIS-Aqua Sea Surface Temperature (SST) is used to validate a mathematical model to retrieve surface fluxes in a Mediterranean coastal lagoon (Mar Menor, S-E Spain). El objetivo de esta tesis es de desarrollar y evaluar herramientas y aplicaciones de la teledetección para estimar flujos de superficie en zonas semiáridas. En una primera parte (Capítulo 4), se evalúa la fiabilidad de una nueva parametrización para estimar el flujo de calor en el suelo (G) con el fin de ser utilizado en métodos de estimación de la evapotranspiración (ET) usando datos de teledetección. La parametrización de G se optimiza usando datos de flujo de energía obtenido durante las campañas del proyecto AMMA, y muestra buenos resultados y una mejora de las estimaciones del flujo de calor sensible (H) y de ET cuando se utiliza conjuntamente con el método del triángulo (Jiang & Islam, 2001). En una segunda parte (Capítulo 5), el método del triángulo se compara con valores de ET estimado por un modelo de superficie terrestre (JULES). Se intenta calibrar JULES usando el método del triángulo mediante simulaciones de Monte Carlo, pero los dos métodos muestran resultados muy diferentes, indicando que se necesita tareas de comparación profundizadas para poder evaluar la eficacia de estos modelos (de superficie terrestre y basados en la teledetección) para estimar los flujos de energía a la superficie. El capítulo 6 presenta un conjunto de ejemplos de aplicaciones operacionales para estimar los flujos de superficie usando datos de teledetección. El primer ejemplo consiste en el estudio de la evolución temporal de mapas de ET en África occidental bajo la influencia del monzón africano. En el segundo ejemplo, se aplica la nueva parametrización de G descrita en el capítulo 4 para calcular y analizar la evolución a largo plazo (2000-2009) de los componentes del balance de energía a la superficie, G, H y ET, en diferentes puntos de la cuenca del río Segura (Sureste español) utilizando datos del sensor MODIS-Terra (temperatura superficial y NDVI). La distribución temporal y espacial de ET revela diferentes controles sobre ET. En el último ejemplo, datos de temperatura superficial del mar del sensor MODIS-Aqua se utilizaron para validar un modelo matemático para calcular los flujos superficiales de una laguna costera del Mediterráneo (Mar Menor en el Sureste español).

Epinephrine in cardiac arrest: systematic review and meta-analysis.

PubMed

Morales-Cané, Ignacio; Valverde-León, María Del Rocío; Rodríguez-Borrego, María Aurora

2016-12-08

evaluate the effectiveness of epinephrine used during cardiac arrest and its effect on the survival rates and neurological condition. systematic review of scientific literature with meta-analysis, using a random effects model. The following databases were used to research clinical trials and observational studies: Medline, Embase and Cochrane, from 2005 to 2015. when the Return of Spontaneous Circulation (ROSC) with administration of epinephrine was compared with ROSC without administration, increased rates were found with administration (OR 2.02. 95% CI 1.49 to 2.75; I2 = 95%). Meta-analysis showed an increase in survival to discharge or 30 days after administration of epinephrine (OR 1.23; 95% IC 1.05-1.44; I2=83%). Stratification by shockable and non-shockable rhythms showed an increase in survival for non-shockable rhythm (OR 1.52; 95% IC 1.29-1.78; I2=42%). When compared with delayed administration, the administration of epinephrine within 10 minutes showed an increased survival rate (OR 2.03; 95% IC 1.77-2.32; I2=0%). administration of epinephrine appears to increase the rate of ROSC, but when compared with other therapies, no positive effect was found on survival rates of patients with favorable neurological status. avaliar a efetividade da adrenalina na parada cardíaca e seu efeito na sobrevivência e no estado neurológico. revisão sistemática da literatura científica com meta-análise utilizando um modelo de efeitos aleatórios. Revisão em Medline, Embase e Cochrane, desde 2005 até 2015 de ensaios clínicos e estudos observacionais. observou-se aumento nas taxas de retorno de circulação espontânea com a administração de adrenalina (OR 2,02; 95% IC 1,49-2,75; I2=95%) comparadas com a não administração de adrenalina. A meta-análise mostrou um aumento da sobrevivência na alta ou depois de 30 dias da administração de adrenalina (OR 1,23; 95% IC 1,05-1,44; I2=83%). Quando estratificados por ritmos desfibrilháveis e não desfibrilháveis apareceu um aumento da sobrevivência nos ritmos não desfibrilháveis (OR 1,52; 95% IC 1,29-1,78; I2=42%). Também observou-se um incremento de sobrevivência na alta ou depois de 30 dias, quando administrada a adrenalina antes de 10 minutos, isto comparado com administração tardia (OR 2,03; 95% IC 1,77-2,32; I2=0%). a administração de adrenalina parece incrementar a taxa de retorno da circulação espontânea, mas não se tem encontrado um efeito positivo nas taxas de sobrevivência nem nas taxas de pacientes com estado neurológico favorável, em comparação com outras terapias. evaluar la efectividad de la adrenalina en el paro cardíaco y su efecto en la supervivencia y en el estado neurológico. revisión sistemática de la literatura científica con metaanálisis utilizando un modelo de efectos aleatorios. Revisión en Medline, Embase y Cochrane, desde 2005 hasta 2015, de ensayos clínicos y estudios observacionales. se observó aumento en las tasas de retorno de circulación espontánea cuando administrada adrenalina (OR 2,02; 95% IC 1,49-2,75; I2=95%) comparada con la no administración de adrenalina. El metaanálisis mostró un aumento de la supervivencia al alta hospitalaria o a los 30 días cuando administrada adrenalina (OR 1,23; 95% IC 1,05-1,44; I2=83%). La estratificación por ritmos desfibrilables y no desfibrilables mostró un aumento de la supervivencia en ritmos no desfibrilables (OR 1,52; 95% IC 1,29-1,78; I2=42%). También, se observó un incremento en la supervivencia al alta hospitalaria o a los 30 días en la administración de adrenalina antes de 10 minutos comparada con la administración tardía (OR 2,03; 95% IC 1,77-2,32; I2=0%). la administración de adrenalina parece incrementar la tasa de retorno de circulación espontánea, pero no se ha encontrado un efecto positivo en tasas de supervivencia ni en tasas de pacientes con estado neurológico favorable, en comparación con otras terapias.

Factors associated with suicidal ideation among university students.

PubMed

Santos, Hugo Gedeon Barros Dos; Marcon, Samira Reschetti; Espinosa, Mariano Martínez; Baptista, Makilin Nunes; Paulo, Paula Mirianh Cabral de

2017-05-15

to analyze the factors associated with suicidal ideation in a representative sample of university students. cross-sectional study, carried out with 637 students of the Federal University of Mato Grosso. The presence of suicidal ideation, demographic and socioeconomic variables, use of alcohol through the Alcohol, Smoking and Substance Involvement Screening Test, and depressive symptoms (Major Depression Inventory) were investigated. Bivariate analysis was performed with the Chi-square test and multivariate analysis using the Poisson regression model. it was found that 9.9% of the students had suicidal thoughts in the previous 30 days and, in the bivariate analysis, the variables economic class, sexual orientation, religious practice, suicide attempts in the family and among friends, alcohol consumption and depressive symptoms were associated with suicidal ideation. In the multivariate analysis sexual orientation, suicide attempts in the family and the presence of depressive symptoms remained as associated factors. these findings constitute a situational diagnosis that enables the formulation of academic policies and preventive actions to confront this situation on the university campus. analisar os fatores associados à ideação suicida em uma amostra representativa de estudantes universitários. estudo transversal analítico, realizado com 637 estudantes de uma Universidade Federal de Mato Grosso. Investigadas variáveis de presença de ideação suicida, demográficas e socioeconômica, uso de álcool por meio do Alcohol, Smoking and Substance Involvement Screening Test, e sintomas depressivos (Inventário de Depressão Maior). A análise bivariada foi realizada com o teste do Qui-quadrado, e a análise múltipla pelo modelo de regressão Poisson. constatou-se que 9,9% dos estudantes tinham ideias suicidas nos últimos 30 dias, e na análise bivariada as variáveis classe econômica, orientação sexual, prática religiosa, tentativas de suicídio na família e entre amigos, consumo de álcool e sintomas depressivos apresentaram associação com ideação suicida. Na análise múltipla permaneceu como fatores associados orientação sexual, tentativas de suicídio na família e presença de sintomas depressivos. tais achados constituem um diagnóstico situacional que possibilita a formulação de políticas acadêmicas e de ações de prevenção para o enfrentamento dessa situação no campus universitário. analizar los factores asociados a la ideación suicida en una muestra representativa de estudiantes universitarios. estudio transversal analítico, realizado con 637 estudiantes en una Universidad Federal de Mato Grosso. Fueron investigadas las variables: presencia de ideación suicida; demográficas y socioeconómicas; uso de alcohol por medio del Alcohol, Smoking and Substance Involvement Screening Test; y síntomas depresivos (Inventario de Depresión Mayor). El análisis bivariado fue realizado con el test de Chi-cuadrado y el análisis múltiple con el modelo de regresión de Poisson. se constató que 9,9% de los estudiantes tuvieron ideas suicidas en los últimos 30 días, y en el análisis bivariado las variables: clase económica; orientación sexual; práctica religiosa; intentos de suicidio en la familia y entre amigos; consumo de alcohol; y síntomas depresivos, presentaron asociación con ideación suicida. En el análisis múltiple permanecieron como factores asociados la orientación sexual, los intentos de suicidio en la familia y la presencia de síntomas depresivos. estos hallazgos constituyen un diagnóstico situacional que posibilita la formulación de políticas académicas y de acciones de prevención para enfrentar esa situación en el campus universitario.

Analisis experimental de la propagacion en redes de area corporal para la banda de ultra wideband. experimental characterization of the propagation in ultra wideband body area networks

NASA Astrophysics Data System (ADS)

Garcia Serna, Ruben Gregorio

Diferentes dispositivos capaces de obtener informacion sobre parametros fisiologicos, cinematicos o contextuales del cuerpo pueden interconectarse de manera inalambrica dando lugar a las denominadas Redes de Area Corporal Inalambricas (WBAN, Wireless Body Area Networks). De entre las posibles tecnologias para establecer los enlaces, Ultra Wideband (UWB) esta captando cada vez un mayor interes debido a caracteristicas tales como el bajo nivel de potencia de transmision requerido (bajo nivel de exposicion a campos electromagneticos), el alto ancho de banda disponible y la alta resolucion temporal/espacial. El diseno de sistemas centrados en el cuerpo requiere de modelos de canal que describan de manera precisa la propagacion de senales en este tipo de entornos. Esta tesis se plantea con el objetivo de contribuir al estudio experimental de la propagacion en sistemas centrados en el cuerpo operando en la banda UWB. En primer lugar, se presenta un marco introductorio a las redes WBAN, sus elementos constitutivos, bandas de frecuencia, estandarizacion y modelos de canal. Ademas, se introducen los fundamentos de la tecnologia UWB y sus aplicaciones en este area. Seguidamente, se analiza en terminos de las perdidas de propagacion y la dispersion de retardo la propagacion en el canal off-body entre un transmisor fijo y un dispositivo receptor colocado sobre la superficie del cuerpo de un sujeto. Se considera la influencia de diferentes aspectos, tales como el entorno de medidas, la posicion de colocacion de una antena sobre el cuerpo y la postura adoptada por un sujeto. Finalmente, se analiza el canal de propagacion in-body considerando el movimiento relativo entre dos dispositivos causado por efecto de la respiracion. Las condiciones de propagacion en el interior del cuerpo se emulan por medio de un phantom liquido para UWB y la caracterizacion se plantea tanto en frecuencia, en terminos del modelado de la forma y el ensanchamiento del espectro Doppler, como en tiempo, por medio del estudio de la funcion de autocorrelacion y el tiempo de coherencia del canal.

Modelo B/Dual Language Programmes in the Basque Country and the USA

ERIC Educational Resources Information Center

Torres-Guzman, Maria E.; Etxeberria, Feli

2005-01-01

In this paper, we undertake a cross-national comparison of early partial immersion programmes, known as dual language or Modelo B programmes, in the USA and the Basque Country in Spain, respectively. We attempt to make sense of their growth, the expanded social uses of the minority languages, and address seemingly contradictory pedagogical…

Linking Indices for Biodiversity Monitoring to Extinction Risk Theory

PubMed Central

Mccarthy, Michael A; Moore, Alana L; Krauss, Jochen; Morgan, John W; Clements, Christopher F

2014-01-01

Biodiversity indices often combine data from different species when used in monitoring programs. Heuristic properties can suggest preferred indices, but we lack objective ways to discriminate between indices with similar heuristics. Biodiversity indices can be evaluated by determining how well they reflect management objectives that a monitoring program aims to support. For example, the Convention on Biological Diversity requires reporting about extinction rates, so simple indices that reflect extinction risk would be valuable. We developed 3 biodiversity indices that are based on simple models of population viability that relate extinction risk to abundance. We based the first index on the geometric mean abundance of species and the second on a more general power mean. In a third index, we integrated the geometric mean abundance and trend. These indices require the same data as previous indices, but they also relate directly to extinction risk. Field data for butterflies and woodland plants and experimental studies of protozoan communities show that the indices correlate with local extinction rates. Applying the index based on the geometric mean to global data on changes in avian abundance suggested that the average extinction probability of birds has increased approximately 1% from 1970 to 2009. Conectando Índices para el Monitoreo de la Biodiversidad con la Teoría de Riesgo de Extinción Resumen Los índices de biodiversidad combinan frecuentemente los datos de diferentes especies cuando se usan en los programas de monitoreo. Las propiedades heurísticas pueden sugerir índices preferidos, pero carecemos de medios objetivos para discriminar a los índices con propiedades heurísticas similares. Los índices de biodiversidad pueden evaluarse al determinar qué tan bien reflejan los objetivos de manejo que un programa de monitoreo busca apoyar. Por ejemplo, la Convención sobre la Diversidad Biológica requiere reportar las tasas de extinción, así que los índices que reflejan el riesgo de extinción serían valiosos. Desarrollamos 3 índices de biodiversidad que se basan en modelos sencillos de viabilidad de población y que relacionan el riesgo de extinción con la abundancia. Basamos el primer índice en la media geométrica de la abundancia de especies, y el segundo en una media de poder más general. En el tercer índice integramos la media geométrica y la tendencia. Estos índices requieren los mismos datos que índices previos, pero también se relacionan directamente con el riesgo de extinción. La información de campo sobre mariposas y plantas de bosque, y los estudios experimentales de comunidades protozoarias, muestran que los índices se correlacionan con las tasas locales de extinción. Al aplicar el índice basado en la media geométrica sobre los datos globales de los cambios en la abundancia de aves, sugirió que la probabilidad de extinción promedio de aves ha incrementado aproximadamente 1% desde 1970 hasta 2009. Palabras Clave Índice de biodiversidad, media geométrica, medida de la biodiversidad, riesgo de extinción PMID:24820139

Service-Learning in Physical Education Teacher Training. Physical Education in the Modelo Prison, Barcelona

ERIC Educational Resources Information Center

Lleixà, Teresa; Ríos, Merche

2015-01-01

In the Psychiatric Unit of the Modelo Prison, Barcelona, a physical education programme is carried out annually with the participation of University of Barcelona (UB) students. In this context, we carried out a study based on service-learning parameters. The aim of the study was twofold: to determine the impact on inmates of the physical education…

Usefulness of the Diagnosis "Decreased Cardiac Output (00029)" in Patients With Chronic Heart Failure.

PubMed

Rojas Sánchez, Lyda Zoraya; Hernández Vargas, Juliana Alexandra; Trujillo Cáceres, Silvia Juliana; Roa Díaz, Zayne Milena; Jurado Arenales, Adriana Milena; Toloza Pérez, Yesith Guillermo

2017-10-01

To determine the clinical and construct validity of the nursing diagnosis "decreased cardiac output" (DCO) in patients with chronic heart failure. Cross-sectional study. A total of 200 people were studied. The defining characteristics with the highest prevalence were as follows: arrhythmia (62.5%) and fatigue (61.5%). Adjustment measures such as infit and outfit were maintained between 0.50 and 1.56 and the total variance explained by the measures was 29.3%. This study determined the clinical validity of the nursing diagnosis DCO. Regarding construct validity, adjustment of the defining characteristics to the Rasch model was observed. This study improves the evidence-based practice of nursing and strengthened the role of the nurse who leads care to this population. Determinar la validez clínica y de constructo del diagnóstico de enfermería "Disminución del Gasto Cardíaco" en pacientes con falla cardíaca crónica. MÉTODOS: Estudio de corte transversal. Un total de 200 pacientes fueron estudiados. Las características definitorias con las mayores prevalencias fueron: arritmia (62.5%) y fatiga (61.5%). Medidas de ajuste como el infit y outfit se mantuvieron entre 0.50 y 1.56. El total de la varianza explicada por las medidas fue de 29.3%. Este estudio determinó la validez clínica del diagnóstico de enfermería "Disminución del Gasto Cardíaco". En cuanto a la validez de constructo, se observó que 19 de las 21 características definitorias se ajustaron al modelo Rasch. IMPLICACIONES PARA LA PRÁCTICA DE ENFERMERÍA: Este estudio mejora la práctica basada en la evidencia de enfermería y fortalece el rol de las enfermeras que lideran el cuidado en esta población. © 2016 NANDA International, Inc.

Obtaining of High Cr Content Cast Iron Materials

NASA Astrophysics Data System (ADS)

Florea, C.; Bejinariu, C.; Carcea, I.; Cimpoesu, N.; Chicet, D. L.; Savin, C.

2017-06-01

We have obtained, through the classic casting process, 3 highly chromium-based experimental alloys proposed for replacing the FC 250 classical cast iron in braking applications. Casting was carried out in an induction furnace and cast into moulds made of KALHARTZ 8500 resin casting mixture and HARTER hardener at SC RanCon SRL Iasi. It is known that the microstructure of the cast iron is a combination of martensite with a small amount of residual austenite after the heat treatment of the ingot. In the case of high-alloy chromium alloys, the performance of the material is due to the presence of M7C3 carbides distributed in the iron matrix Resistance to machining and deformation is based on alloy composition and microstructure, while abrasion resistance will depend on properties and wear conditions.

Is there any link between accreditation programs and the models of organizational excellence?

PubMed

Berssaneti, Fernando Tobal; Saut, Ana Maria; Barakat, Májida Farid; Calarge, Felipe Araujo

2016-01-01

To evaluate whether accredited health organizations perform better management practices than non-accredited ones. The study was developed in two stages: a literature review, and a study of multiple cases in 12 healthcare organizations in the state of São Paulo, Brazil. It surveyed articles comparing hospital accreditation with the EFQM (European Foundation for Quality Management) model of excellence in management. According to the pertinent literature, the accreditation model and the EFQM model are convergent and supplementary in some aspects. With 99% confidence, one can say that there is evidence that accredited organizations scored better in the evaluation based on the EFQM model in comparison to non-accredited organizations. This result was also confirmed in the comparison of results between the categories Facilitators and Results in the EFQM model. There is convergence between the accreditation model and the EFQM excellence model, suggesting that accreditation helps the healthcare sector to implement the best management practices already used by other business sectors. Avaliar se as organizações de saúde acreditadas possuem melhores práticas de gestão do que as não acreditadas. A pesquisa foi dividida em duas etapas: revisão da literatura e estudo de casos múltiplos com 12 organizações de saúde, localizadas no estado de São Paulo ‒ Brasil. Foram pesquisados artigos que comparavam a acreditação hospitalar com o modelo de excelência em gestão da EFQM (European Foundation for Quality Management), sendo que a literatura pertinente considera que o modelo de acreditação e o modelo da EFQM são convergentes e, ao mesmo tempo, complementares em determinados aspectos. Com 99% de confiança, pode-se afirmar que há evidência de que as organizações com acreditação obtiveram uma pontuação maior na avaliação baseada no modelo EFQM comparativamente às organizações não acreditadas. Este resultado também se confirmou na comparação dos resultados das categorias Facilitadores e Resultados do modelo EFQM. Há uma convergência entre o modelo de acreditação e o modelo de excelência da EFQM, sugerindo que a acreditação contribui para o setor de saúde implementar as melhores práticas de gestão já difundidas em outros setores de negócio.

NOAA Weather Radio

Science.gov Websites

unidades portátiles portátiles que atiende clima radiofónicas, a los modelos de escritorio y consola que específica o modelo del receptor. Las listas siguientes, que contienen algunos de los muchos NOAA Weather , dependiendo del número de características incluidas. Multi-multi-Band/función de receptores: los receptores

Distribution of a Community of Mammals in Relation to Roads and Other Human Disturbances in Gabon, Central Africa

PubMed Central

Vanthomme, Hadrien; Kolowski, Joseph; Korte, Lisa; Alonso, Alfonso

2013-01-01

Abstract We present the first community-level study of the associations of both roads and other human disturbances with the distribution of mammals in Gabon (central Africa). Our study site was in an oil concession within a littoral mosaic landscape. We conducted surveys along 199 line transects and installed camera traps on 99 of these transects to document mammal presence and abundance. We used generalized linear mixed-effect models to document associations between variables related to the ecosystem (land cover, topography, and hydrology), roads (coating, width of rights of way, condition, type of vehicle used on the road, traffic level, affiliation of users, and general type of road), and other human disturbances (urbanization, agriculture, hunting, logging, gathering, and industrial activities) and the abundance or presence of 17 species or groups of mammals including elephant (Loxodonta cyclotis), buffalo (Syncerus caffer), sitatunga (Tragelaphus spekei), red river hog (Potamochoerus porcus), smaller ungulates, gorilla (Gorilla gorilla), chimpanzee (Pan troglodytes), side-striped jackal (Canis adustus), carnivores, monkeys, and large rodents. Some types of roads and other human disturbances were negatively associated with the abundance or presence of elephants, buffalos, gorillas, sitatungas, some monkeys, and duikers. The pattern of associations of mammals with roads and other human disturbances was diverse and included positive associations with road presence (red river hog, some monkeys, and duikers), agriculture (sitatunga, small carnivores, and large rodents) and industrial activities (sitatunga, red river hog, red duikers, and side-striped jackal). Our results suggest that the community of mammals we studied was mostly affected by hunting, agriculture, and urbanization, which are facilitated by road presence. We recommend increased regulation of agriculture, hunting, and road building in the area. Distribución de una Comunidad de Mamíferos en Relación a Carreteras y Otras Perturbaciones Humanas en Gabón, Africa Central Resumen Presentamos el primer estudio a nivel de comunidad de la relación entre carreteras y otras perturbaciones humanas con la distribución de mamíferos en Gabón (África central). Nuestro sitio de estudio está dentro de una concesión petrolera en un paisaje litoral heterogéneo. Realizamos muestreos a lo largo de 199 transectos lineales e instalamos cámaras trampa en 99 de ellos para documentar la presencia y abundancia de mamíferos. Utilizamos modelos lineales generalizados con efectos mixtos para documentar las asociaciones entre variables relacionadas con el ecosistema (cobertura de suelo, topografía e hidrología), carreteras (tipo de revestimiento, ancho de derecho de vía, condición, tipo de vehículos que utilizan la carretera, nivel de tráfico, afiliación de los usuarios y el tipo general de carretera) y otras perturbaciones humanas (urbanización, agricultura, caza, tala, recolecta y actividades industriales) y la abundancia o presencia de 17 especies o grupos de mamíferos incluyendo elefantes (Loxodonta cyclotis), búfalo (Syncerus caffer), sitatunga (Tragelaphus spekei), cerdo rojo de río (Potomochoerus porcus), ungulados pequeños, gorila (Gorilla gorilla), chimpancé (Pan troglodytes), chacal con rayas a los lados (Canis adustus), carnívoros, monos y roedores de talla grande. Ciertos tipos de carreteras y otras perturbaciones humanas estuvieron asociadas negativamente con la abundancia o presencia de elefantes, búfalos, gorilas, sitatungas, algunos monos y antílopes. Los patrones de asociación de mamíferos con carreteras y otras perturbaciones humanas fueron diversos e incluyen asociaciones positivas con la presencia de carreteras (cerdo rojo de río, algunos monos y antílopes), agricultura (sitatunga, carnívoros pequeños y roedores de talla grande) y actividades industriales (sitatunga, cerdo rojo de río, antílope rojo y chacal con rayas a los lados). Nuestros resultados sugieren que la comunidad de mamíferos que estudiamos fue afectada principalmente por la caza, agricultura y urbanización, que son facilitadas por la presencia de carreteras. Recomendamos una mayor regulación de la agricultura, caza y construcción de carreteras en el área. PMID:23410077

Distribution of stable isotopes in arid storms . II. A double-component model of kinematic wave flow and transport

NASA Astrophysics Data System (ADS)

Yakirevich, Alexander; Dody, Avraham; Adar, Eilon M.; Borisov, Viacheslav; Geyh, Mebus

A new mathematical method based on a double-component model of kinematic wave flow and approach assesses the dynamic isotopic distribution in arid rain storms and runoff. This model describes the transport and δ18O evolution of rainfall to overland flow and runoff in an arid rocky watershed with uniformly distributed shallow depression storage. The problem was solved numerically. The model was calibrated using a set of temporal discharge and δ18O distribution data for rainfall and runoff collected on a small rocky watershed at the Sede Boker Experimental Site, Israel. Simulation of a reliable result with respect to observation was obtained after parameter adjustment by trial and error. Sensitivity analysis and model application were performed. The model is sensitive to changes in parameters characterizing the depression storage zones. The model reflects the effect of the isotopic memory in the water within the depression storage between sequential rain spells. The use of the double-component model of kinematic wave flow and transport provides an appropriate qualitative and quantitative fitting between computed and observed δ18O distribution in runoff. RésuméUne nouvelle méthode mathématique basée sur un modèle à double composante d'écoulement et de transport par une onde cinématique a été développée pour évaluer la distribution dynamique en isotopes dans les précipitations et dans l'écoulement en région aride. Ce modèle décrit le transport et les variations des δ18O de la pluie vers le ruissellement et l'écoulement de surface dans un bassin aride rocheux où le stockage se fait dans des dépressions peu profondes uniformément réparties. Le problème a été résolu numériquement. Le modèle a été calibré au moyen d'une chronique de débits et d'une distribution des δ18O dans la pluie et dans l'écoulement de surface sur un petit bassin versant rocheux du site expérimental de Sede Boker (Israël). La simulation d'un résultat crédible par rapport aux observations a été obtenu après un ajustement des paramètres par une méthode d'essais et d'erreurs. L'analyse de sensibilité et l'application du modèle ont ensuite été réalisés. Le modèle est plutôt sensible aux changements des paramètres caractérisant les zones de stockage dans les dépressions. Le modèle rend compte de l'effet de mémoire isotopique dans l'eau dans le stockage des dépressions entre les événements séquentiels de pluie. L'utilisation d'un modèle à double composante d'écoulement et de transport par onde cinématique permet un ajustement qualitatif et quantitatif adapté entre les distributions des δ18O calculées et observées dans l'écoulement de surface. Resumen Un nuevo método matemático basado en un modelo de doble componente de onda cinemática de flujo y transporte permite caracterizar la distribución isotópica dinámica de las tormentas en zonas áridas y la escorrentía. Este modelo describe el transporte y la evolución del δ18O en la lluvia, flujo superficial y escorrentía en una cuenca rocosa de clima árido con detención superficial distribuida uniformemente. El modelo se calibró numéricamente utilizando un conjunto de datos de descarga temporal y de distribución de δ18O para lluvia y escorrentía recogida en una pequeña cuenca rocosa en el Centro de Experimentación de Sede Boker, Israel. Se obtuvo un buen ajuste a los datos tras un ajuste de parámetros mediante prueba y error. Se realizó un análisis de sensibilidad que indicó que el modelo resulta ser bastante sensible a cambios en los parámetros que caracterizan las zonas de baja detención superficial. El modelo también refleja el efecto de la memoria isotópica en el agua de estas zonas de detención entre los distintos periodos de lluvias. El uso de un modelo de doble componente de onda cinemática de flujo y transporte proporciona un buen ajuste cualitativo y cuantitativo entre los datos medidos y calculados de δ18O en la escorrentía.

CONFLICT OF INTERESTS AS A PROBLEM OF EVIDENCE-BASED MEDICINE.

PubMed

Arpent'eva, M P

The role of ideology (principles) of evidence-based medicine in prophylaxis and correction of con?flict of interests in various spheres of medicine and socio-medical assistance is considered. Professional ethics formed in the course of education and undergoing modification under conditions of real practical work is a main sphere of medical and related edological practices associated with conflicts of interests. Of special importance are principles of bioethics based on the requiremnents of evidence- based medicine. The role of evidence-based medicine in prophylaxis and resolution of conflicts of interests is related to the training and re-training of specialists, prevention and correction of their professional degradation and deformation in the course ofpractical clinical work. Analysis of prima, y and secondary motives underlying occupational out. activities and their role in the formation of the conflict of interests was carried.

Climate change impacts on groundwater resources: modelled deficits in a chalky aquifer, Geer basin, Belgium

NASA Astrophysics Data System (ADS)

Brouyère, Serge; Carabin, Guy; Dassargues, Alain

An integrated hydrological model (MOHISE) was developed in order to study the impact of climate change on the hydrological cycle in representative water basins in Belgium. This model considers most hydrological processes in a physically consistent way, more particularly groundwater flows which are modelled using a spatially distributed, finite-element approach. Thanks to this accurate numerical tool, after detailed calibration and validation, quantitative interpretations can be drawn from the groundwater model results. Considering IPCC climate change scenarios, the integrated approach was applied to evaluate the impact of climate change on the water cycle in the Geer basin in Belgium. The groundwater model is described in detail, and results are discussed in terms of climate change impact on the evolution of groundwater levels and groundwater reserves. From the modelling application on the Geer basin, it appears that, on a pluri-annual basis, most tested scenarios predict a decrease in groundwater levels and reserves in relation to variations in climatic conditions. However, for this aquifer, the tested scenarios show no enhancement of the seasonal changes in groundwater levels. Un modèle hydrologique intégré (MOHISE) a été développé afin d'étudier l'impact du changement climatique sur le cycle hydrologique de bassins versants représentatifs de Belgique. Ce modèle prend en compte tous les processus hydrologiques d'une manière physiquement consistante, plus particulièrement les écoulements souterrains qui sont modélisés par une approche spatialement distribuée aux éléments finis. Grâce à cet outil numérique précis, après une calibration et une validation détaillées, des interprétations quantitatives peuvent être réalisées à partir des résultats du modèle de nappe. Considérant des scénarios de changements climatiques de l'IPCC, l'approche intégrée a été appliquée pour évaluer l'impact du changement climatique sur le cycle de l'eau du bassin du Geer en Belgique. Le modèle de nappe est décrit en détail et les résultats sont discutés en terme d'impact du changement climatique sur l'évolution des réserves souterraines. Les premiers résultats indiquent que des déficits d'eau souterraine peuvent apparaître dans le futur en Belgique. Se ha desarrollado un modelo hidrológico integrado (MOHISE) para estudiar el impacto del cambio climático en el ciclo hidrológico de cuencas representativas en Bélgica. Este modelo considera todos los procesos hidrológicos de forma coherente, especialmente en relación con los flujos de aguas subterráneas, que son modelados por medio de un enfoque de elementos finitos espacialmente distribuidos. Gracias a esta herramienta numérica precisa, y tras una calibración y validación detalladas, se puede obtener interpretaciones cuantitativas de los resultados del modelo del acuífero. Considerando escenarios de cambio climático IPCC, se ha aplicado el enfoque integrado a la evaluación del impacto de dicho cambio climático en el ciclo hidrológico de la cuenca del Geer. Se describe los detalles y resultados del modelo de las aguas subterráneas en términos del impacto del cambio climático en la evolución de las reservas de los acuíferos. Los resultados preliminares indican que es posible esperar déficits de aguas subterráneas en un futuro en Bélgica.

Melhoramentos no código Wilson-Devinney para binárias eclipsantes

NASA Astrophysics Data System (ADS)

Vieira, L. A.; Vaz, L. P. R.

2003-08-01

A análise de curvas de luz e velocidades radiais de sistemas binários eclipsantes pode ser feita por meio de vários modelos. Um desses é o Modelo Wilson-Devinney (WD). Ao longo dos anos, esse modelo sofreu várias alterações em seus códigos principais, com a finalidade de torná-lo mais consistente tanto fíisica como numericamente. O Modelo WD tem sido melhorado de várias maneiras em seus dois códigos: um para a predição das curvas de luz teórica e de velocidade radiais e outra para as soluções destas curvas. Teoricamente, na física do modelo, nós introduzimos a possibilidade de levar em conta os efeitos do movimento apsidal. Numericamente, nós introduzimos a possibilidade de usar o Método SIMPLEX no procedimento da solução, como uma alternativa para o já implementado Método de Mínimos Quadrados (Least Squares Method). Estas modificações, juntamente com outras já introduzidas pelo nosso grupo anteriormente, tornam o código mais eficiente na solução das curvas de luz e de velocidade radiais de binárias eclipsantes. Como o modelo tem sido usado para analisar sistemas com componentes pré-sequência principal (TY CrA, Casey et al. 1998, Vaz et al. 1998), SM 790, Stassun et al. 2003), este melhoramento beneficiará estes casos também. Apresentamos os resultados obtidos com a modificação do código WD por meio do uso de dados da estrela GL Carinae, comprovando, (1) que os parâmetros orbitais calculados por nós são coerentes com os obtidos anteriormente na literatura (Giménez & Clausen, 1986) e com os obtidos por Faria (1987), e (2) que a implementação do Método SIMPLEX torna o código mais lento mas completamente consistente internamente e evita os problemas gerados pelo uso do Método de Mínimos Quadrados, tais como imprecisão no cálculo das derivadas parciais e convergência para mínimos locais.

Three-dimensional mathematical model to simulate groundwater flow in the lower Palar River basin, southern India

NASA Astrophysics Data System (ADS)

Senthilkumar, M.; Elango, L.

A three-dimensional mathematical model to simulate regional groundwater flow was used in the lower Palar River basin, in southern India. The study area is characterised by heavy ion of groundwater for agricultural, industrial and drinking water supplies. There are three major pumping stations on the riverbed apart from a number of wells distributed over the area. The model simulates groundwater flow over an area of about 392 km2 with 70 rows, 40 columns, and two layers. The model simulated a transient-state condition for the period 1991-2001. The model was calibrated for steady- and transient-state conditions. There was a reasonable match between the computed and observed heads. The transient model was run until the year 2010 to forecast groundwater flow under various scenarios of overpumping and less recharge. Based on the modelling results, it is shown that the aquifer system is stable at the present rate of pumping, excepting for a few locations along the coast where the groundwater head drops from 0.4 to 1.81 m below sea level during the dry seasons. Further, there was a decline in the groundwater head by 0.9 to 2.4 m below sea level in the eastern part of the area when the aquifer system was subjected to an additional groundwater withdrawal of 2 million gallons per day (MGD) at a major pumping station. Les modèles mathématiques en trois dimensions de l'écoulement souterrain régional sont très utiles pour la gestion des ressources en eau souterraine, car ils permettent une évaluation des composantes des processus hydrologiques et fournissent une description physique de l'écoulement de l'eau dans un aquifère. Une telle modélisation a été entreprise sur une partie du bassin inférieur de la rivière Palar, dans le sud de l'Inde. La zone d'étude est caractérisée par des prélèvements importants d'eau souterraine pour l'agriculture, l'industrie et l'eau potable. Il existe trois grandes stations de pompage sur la rivière en plus d'un certain nombre de puits répartis dans cette région. Le modèle simule l'écoulement souterrain dans une région d'environ 392 km2 avec 70 rangs, 40 colonnes et deux couches. Le modèle a fonctionné en régime transitoire en utilisant une approximation aux différences finies d'une équation différentielle partielle en trois dimensions de l'écoulement souterrain dans cet aquifère pour la période 1991-2001. Le modèle a été calibré pour des conditions de régime permanent et transitoire. Les charges hydrauliques calculées étaient en bon accord avec celles observées. Sur la base des résultats du modèle, il est apparu que le système aquifère est stable pour ce taux de pompage, excepté en quelques sites le long de la côte où l'eau marine a pénétré 50-100 m dans les terres. Le modèle transitoire a tourné jusqu'en 2010 afin de prévoir l'écoulement souterrain dynamique pour différents scénarios de pompage excessif et de recharge réduite. Il se produit un abaissement de la piézométrie de la nappe de 0.6 à 0.8 m dans la partie orientale, alors que l'aquifère est soumis à un prélèvement supplémentaire de 8,000 m3/jour à l'une des stations principales de pompage. Même avec le niveau actuel de pompage, la piézométrie de la nappe descendrait sous le niveau de la mer au cours des saisons sèches. Le modèle prédit le fonctionnement du système aquifère sous différentes conditions de stress hydrologique. Los modelos tridimensionales de flujo de aguas subterráneas son útiles para gestionar los recursos hídricos subterráneos, ya que proporcionan una aproximación a los diversos procesos hidrológicos y una descripción cuantitativa del flujo de agua en el acuífero. Se ha desarrollado un estudio de modelación de este tipo en una parte de la cuenca baja del río Palar, en el Sur de la India. Esta zona se caracteriza por las intensas extracciones de aguas subterráneas para usos agrícolas, industriales y domésticos. Hay tres estaciones de bombeo principales en el río, además de numerosos pozos distribuidos por la zona. El modelo simula el flujo de las aguas subterráneas en una superficie de 392 km2 por medio de 70 filas, 40 columnas y 2 capas. El modelo ha sido empleado en condiciones transitorias, por medio de la aproximación en diferencias finitas de las ecuaciones diferenciales parciales en tres dimensiones del flujo en el acuífero durante el período 1991-2001. Se ha calibrado el modelo en condiciones permanentes y transitorias. El ajuste entre los niveles calculados y medidos es razonable. A partir de los resultados de la modelación, se ha obtenido que el sistema acuífero es estable con la tasa de bombeo utilizada, exceptuando unos pocos emplazamientos a lo largo de la costa, donde se ha dado lugar a fenómenos de intrusión marina en una distancia de 50-100 m. El modelo transitorio ha sido ejecutado hasta el año 2010 para predecir el flujo dinámico bajo diversos escenarios de sobreexplotación y de reducción de la recarga. Se produce una disminución en los niveles piezométricos de 0.6 a 0.8 m en la zona oriental, donde el sistema acuífero está sometido a una extracción adicional de 2 millones de galones por día en la estación principal de bombeo. Incluso con las extracciones actuales, los niveles piezométricos se sitúan bajo el nivel del mar durante las épocas secas. El modelo predice el comportamiento de este sistema acuífero bajo varias condiciones de presión hidrológica.

Estudo de não gaussianidade nas anisotropias da RCF medidas Wmap

NASA Astrophysics Data System (ADS)

Andrade, A. P. A.; Wuensche, C. A.; Ribeiro, A. L. B.

2003-08-01

A investigação do campo de flutuações da Radiação Cósmica de Fundo (RCF) pode oferecer um importante teste para os modelos cosmológicos que descrevem a origem e a evolução das flutuações primordiais. De um lado, apresenta-se o modelo inflacionário que prevê um espectro de flutuações adiabáticas distribuídas segundo uma gaussiana e, de outro, os modelos de defeitos topológicos (dentre outros) que descrevem um mecanismo para a geração de flutuações de isocurvatura que obedecem a uma distribuição não gaussiana. Este trabalho tem como objetivo caracterizar traços do modelo não gaussiano de campo misto (entre flutuações adiabáticas e de isocurvatura) nos mapas do Wilkinson Microwave Anisotropy Probe (WMAP). Simulações das anisotropias da RCF no contexto de mistura indicam traços marcantes na distribuição das flutuações de temperatura, mesmo quando consideradas pequenas contribuições do campo de isocurvatura (da ordem de 0.001). O efeito da mistura entre os campos resulta na transferência de potência de flutuações em escalas angulares intermediárias para flutuações em pequenas escalas angulares. Este efeito pode ser caracterizado pela relação entre as amplitudes dos primeiros picos acústicos no espectro de potência da RCF. Neste trabalho, investigamos a contribuição do campo de isocurvatura, no contexto de mistura, sobre as observações recentes da RCF realizadas pelo WMAP. As previsões do modelo de campo misto, uma vez confrontadas com as observações em pequenas escalas angulares, podem ajudar a revelar a natureza das flutuações primordiais.

Readiness to tackle chronicity in Spanish health care organisations: a two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument

PubMed Central

Mira, José Joaquín; Fernández-Cano, Paloma; Contel, Joan Carlos; Guilabert-Mora, Mercedes; Solas-Gaspar, Olga

2015-01-01

Introduction: The Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument was developed to implement the conceptual framework of the Chronic Care Model in the Spanish national health system. It has been used to assess readiness to tackle chronicity in health care organisations. In this study, we use self-assessments at macro-, meso- and micro-management levels to (a) describe the two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations tool in Spain and (b) assess the validity and reliability of this instrument. Methods: The results from 55 organisational self-assessments were included and described. In addition to that, the internal consistency, reliability and construct validity of Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations were examined using Cronbach's alpha, the Spearman–Brown coefficient and factorial analysis. Results: The obtained scores reflect opportunities for improvement in all dimensions of the instrument. Cronbach's alpha ranged between 0.90 and 0.95 and the Spearman–Brown coefficient ranged between 0.77 and 0.94. All 27 components converged in a second-order factorial solution that explained 53.8% of the total variance, with factorial saturations for the components of between 0.57 and 0.94. Conclusions: Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations is an instrument that allows health care organisations to perform self-assessments regarding their readiness to tackle chronicity and to identify areas for improvement in chronic care. PMID:27118958

Readiness to tackle chronicity in Spanish health care organisations: a two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument.

PubMed

Mira, José Joaquín; Nuño-Solinís, Roberto; Fernández-Cano, Paloma; Contel, Joan Carlos; Guilabert-Mora, Mercedes; Solas-Gaspar, Olga

2015-01-01

The Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations instrument was developed to implement the conceptual framework of the Chronic Care Model in the Spanish national health system. It has been used to assess readiness to tackle chronicity in health care organisations. In this study, we use self-assessments at macro-, meso- and micro-management levels to (a) describe the two-year experience with the Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations tool in Spain and (b) assess the validity and reliability of this instrument. The results from 55 organisational self-assessments were included and described. In addition to that, the internal consistency, reliability and construct validity of Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations were examined using Cronbach's alpha, the Spearman-Brown coefficient and factorial analysis. The obtained scores reflect opportunities for improvement in all dimensions of the instrument. Cronbach's alpha ranged between 0.90 and 0.95 and the Spearman-Brown coefficient ranged between 0.77 and 0.94. All 27 components converged in a second-order factorial solution that explained 53.8% of the total variance, with factorial saturations for the components of between 0.57 and 0.94. Instrumento de Evaluación de Modelos de Atención ante la Cronicidad/Assessment of Readiness for Chronicity in Health Care Organisations is an instrument that allows health care organisations to perform self-assessments regarding their readiness to tackle chronicity and to identify areas for improvement in chronic care.

Modos de produccion cientifica: Culturas y metodologias de investigacion en la Universidad de Cadiz

NASA Astrophysics Data System (ADS)

Gonzalez Ramos, Ana M.

2004-12-01

Este trabajo de investigacion supone un modelo teorico de caracter aplicado, que proporciona la oportunidad de evaluar la produccion cientifica de los investigadores. Se encuadra dentro de la tradiccion de la estadistica aplicada y la sociologia del conocimiento. Atiende especialmente a dos conjuntos de temas de interes, por una parte, las caracteristicas principales que determinan el nivel y tipo de produccion academica producida por las unidades de investigacion y por los propios investigadores; por otra, la utilizacion que se hace de los metodos y tecnicas de investigacion puesto que de ello tambien depende el modo de produccion cientifica. Los puntos novedosos de esta tesis son: la medicion cuantitativa del objeto de estudio, la suma de los productos y las condiciones externas a la produccion del conocimiento mas otros elementos internos como las caracteristicas de los investigadores y la metodologia utilizada para desarrollar sus trabajos; y, finalmente, el uso de las nuevas tecnologias. El aprovechamiento de los recursos estadisticos y las fuentes de informacion secundarias se complementan con el diseno propio de una encuesta donde se implementa las caracteristicas descritas en un capitulo anterior sobre los metodos cientificos mas idoneos descritos en los principales manuales y articulos cientificos desde distintas disciplinas de conocimiento. Dicha encuesta ha sido desarrollada como un programa propio y en base a los mas innovadores usos de la tecnologia en la metodologia de encuestas.

Stability of Lobed Balloons

NASA Technical Reports Server (NTRS)

Ball, Danny (Technical Monitor); Pagitz, M.; Pellegrino, Xu S.

2004-01-01

This paper presents a computational study of the stability of simple lobed balloon structures. Two approaches are presented, one based on a wrinkled material model and one based on a variable Poisson s ratio model that eliminates compressive stresses iteratively. The first approach is used to investigate the stability of both a single isotensoid and a stack of four isotensoids, for perturbations of in.nitesimally small amplitude. It is found that both structures are stable for global deformation modes, but unstable for local modes at su.ciently large pressure. Both structures are stable if an isotropic model is assumed. The second approach is used to investigate the stability of the isotensoid stack for large shape perturbations, taking into account contact between di.erent surfaces. For this structure a distorted, stable configuration is found. It is also found that the volume enclosed by this con.guration is smaller than that enclosed by the undistorted structure.

Biaxial seismic behaviour of reinforced concrete columns =

NASA Astrophysics Data System (ADS)

Rodrigues, Hugo Filipe Pinheiro

A analise dos efeitos dos sismos mostra que a investigacao em engenharia sismica deve dar especial atencao a avaliacao da vulnerabilidade das construcoes existentes, frequentemente desprovidas de adequada resistencia sismica tal como acontece em edificios de betao armado (BA) de muitas cidades em paises do sul da Europa, entre os quais Portugal. Sendo os pilares elementos estruturais fundamentais na resistencia sismica dos edificios, deve ser dada especial atencao a sua resposta sob acoes ciclicas. Acresce que o sismo e um tipo de acao cujos efeitos nos edificios exige a consideracao de duas componentes horizontais, o que tem exigencias mais severas nos pilares comparativamente a acao unidirecional. Assim, esta tese centra-se na avaliacao da resposta estrutural de pilares de betao armado sujeitos a acoes ciclicas horizontais biaxiais, em tres linhas principais. Em primeiro lugar desenvolveu-se uma campanha de ensaios para o estudo do comportamento ciclico uniaxial e biaxial de pilares de betao armado com esforco axial constante. Para tal foram construidas quatro series de pilares retangulares de betao armado (24 no total) com diferentes caracteristicas geometricas e quantidades de armadura longitudinal, tendo os pilares sido ensaiados para diferentes historias de carga. Os resultados experimentais obtidos sao analisados e discutidos dando particular atencao a evolucao do dano, a degradacao de rigidez e resistencia com o aumento das exigencias de deformacao, a energia dissipada, ao amortecimento viscoso equivalente; por fim e proposto um indice de dano para pilares solicitados biaxialmente. De seguida foram aplicadas diferentes estrategias de modelacao nao-linear para a representacao do comportamento biaxial dos pilares ensaiados, considerando nao-linearidade distribuida ao longo dos elementos ou concentrada nas extremidades dos mesmos. Os resultados obtidos com as varias estrategias de modelacao demonstraram representar adequadamente a resposta em termos das curvas envolventes forca-deslocamento, mas foram encontradas algumas dificuldades na representacao da degradacao de resistencia e na evolucao da energia dissipada. Por fim, e proposto um modelo global para a representacao do comportamento nao-linear em flexao de elementos de betao armado sujeitos a acoes biaxiais ciclicas. Este modelo tem por base um modelo uniaxial conhecido, combinado com uma funcao de interacao desenvolvida com base no modelo de Bouc- Wen. Esta funcao de interacao foi calibrada com recurso a tecnicas de otimizacao e usando resultados de uma serie de analises numericas com um modelo refinado. E ainda demonstrada a capacidade do modelo simplificado em reproduzir os resultados experimentais de ensaios biaxiais de pilares.

Development and validation of the Hospitality Axiological Scale for Humanization of Nursing Care.

PubMed

Galán González-Serna, José María; Ferreras-Mencia, Soledad; Arribas-Marín, Juan Manuel

2017-08-03

to develop and validate a scale to evaluate nursing attitudes in relation to hospitality for the humanization of nursing care. Participants: the sample consisted of 499 nursing professionals and undergraduate students of the final two years of the Bachelor of Science in Nursing program. the instrument has been developed and validated to evaluate the ethical values related to hospitality using a methodological approach. Subsequently, a model was developed to measure the dimensions forming the construct hospitality. the Axiological Hospitality Scale showed a high internal consistency, with Cronbach's Alpha=0.901. The validation of the measuring instrument was performed using factorial, exploratory and confirmatory analysis techniques with high goodness of fit measures. the developed instrument showed an adequate validity and a high internal consistency. Based on the consistency of its psychometric properties, it is possible to affirm that the scale provides a reliable measurement of the hospitality. It was also possible to determine the dimensions or sources that embrace it: respect, responsibility, quality and transpersonal care. desenvolver e validar uma escala que permita avaliar a atitude dos enfermeiros em termos de hospitalidade, visando a humanização da enfermagem.Participantes: a amostra foi constituída por 499 profissionais e estudantes de enfermagem dos dois últimos anos do curso de graduação em Enfermagem. utilizando-seuma abordagem metodológica, foi desenvolvido e validado um instrumento para avaliar os valores éticos relacionados com a hospitalidade. Subsequentemente, foi formulado um modelo para mediras dimensões que constituem o construto hospitalidade. a Escala Axiológica de Hospitalidade mostrou uma consistência interna elevada, com Alfa de Cronbach=0,901. A validação do instrumento de medição foi realizada usando-se métodos de análise fatorial, exploratória e confirmatória, que apresentaram bons índices de qualidade de ajuste. o instrumento desenvolvido apresentou uma validade adequada e uma consistência interna elevada. Com base na consistência de suas propriedades psicométricas, é possível afirmar que a escala proporciona uma medida confiável da hospitalidade. Também foi possível determinar as dimensões ou fontes que a compõem: o respeito, a responsabilidade, a qualidade e o cuidado transpessoal. desarrollar y validar una escala que permita evaluar la actitud enfermera ante la hospitalidad para la humanización de enfermería. Participantes: la muestra la componen 499 profesionales de enfermería y estudiantes de los dos últimos niveles académicos de la titulación de Grado en Enfermería. mediante abordaje metodológico, se ha desarrollado y validado un instrumento para evaluar valores éticos relacionados con la hospitalidad. Posteriormente, se ha formulado un modelo de medida de las dimensiones que conforman el constructo hospitalidad. la Escala Axiológica de la Hospitalidad ha mostrado una alta consistencia interna, con un Alfa de Cronbach=0.901. La validación del instrumento de medida se realizó mediante las técnicas de análisis factorial, exploratorio y confirmatorio, que presentaron unos buenos índices de bondad de ajuste. el instrumento desarrollado ha presentado una adecuada validez y una alta consistencia interna. Sus adecuadas propiedades psicométricas permiten afirmar que la escala aporta una medición fiable de la hospitalidad. También ha permitido determinar las dimensiones o fuentes que la conforman: el respeto, la responsabilidad, la calidad y el cuidado transpersonal.

Providing Meaningful Learning for Students of the Sixth Grade of Middle School: a Study on the Moon Phases. (Breton Title: Propiciando Aprendizagem Significativa Para Alunos do Sexto Ano do Ensino Fundamental: um Estudo sobre as Fases da Lua.) Propiciando el Aprendizaje Significativo Para Alumnos del Sexto Nivel de la Educación General Básica: un Estudio sobre Las Fases de la Luna

NASA Astrophysics Data System (ADS)

Darroz, Luiz Marcelo; Samudio Pérez, Carlos Ariel; da Rosa, Cleci Werner; Heineck, Renato

2012-07-01

We relate in this article a didactic experience studying the moon phases with a group of middle school students of a private school of the municipality of Passo Fundo, RS. Based on David Ausubel's Meaningful Learning Theory, we have sought to develop a proposal following a didactic model which simulates the phases of the Moon, as based on the previous conceptions of the students. The signs of learning were evidenced by means of memory registries of the activity. From the obtained results we believe that the proposal achieved its goals, since the students were able to identify, differentiate and transfer the phenomenon of the moon phases to new contexts. Thus, it is concluded that a methodology focused on a meaningful content for the students is fundamental to the construction and genuine grasping of what is being learned. Neste artigo, relata-se uma experiência didática de estudo das fases da Lua com uma turma do 6° ano do Ensino Fundamental, de uma escola privada do município de Passo Fundo, RS. Tendo como fundamentação teórica a Teoria da Aprendizagem Significativa de David Ausubel, buscou-se desenvolver a proposta a partir de um modelo didático que simula as fases da Lua e com base nas concepções prévias dos estudantes. Os indícios da aprendizagem foram constatados através de registros de memórias da atividade. Pelos resultados apresentados, acredita-se que a proposta alcançou seus objetivos, uma vez que os estudantes conseguiram identificar, diferenciar e transferir o fenômeno das fases da Lua para novos contextos. Assim, conclui-se que uma metodologia com enfoque em um conteúdo significativo ao estudante é fundamental para a construção e compreensão genuína do que está sendo aprendido. En este artículo se relata una experiencia didáctica de estudio de las fases de la Luna con una clase de 6º año de la educación general básica de una escuela privada del municipio de Passo Fundo, RS. Teniendo como fundamentación teórica la Teoría del Aprendizaje Significativo de David Ausubel, se buscó desenvolver la propuesta a partir de un modelo didáctico que simula las Fases de la Luna, usando como base las concepciones previas de los estudiantes. Los indicios del aprendizaje fueron verificados a través de registros de memorias de la actividad. Por los resultados obtenidos creemos que la propuesta alcanzó sus objetivos, una vez que los estudiantes consiguieron identificar y transferir el fenómeno de las fases de la Luna para nuevos contextos. Así, se concluye que una metodología con enfoque en un contenido significativo para el estudiante es fundamental para la construcción y comprensión genuina de lo que está siendo aprendido.

Significado de psicólogas/os de atención primaria de salud sobre la intervención psicosocial de grupo en el tratamiento de la depresión en Chile.

PubMed

Andrade, Gonzalo; Espinoza, Adriana

2017-11-01

En Chile, el tratamiento de la depresión en salud pública promueve la realización de Intervenciones Psicosociales en Grupo (IPG) para todos los casos diagnosticados, no obstante, se observa una baja implementación de estas prestaciones. El presente artículo describe y caracteriza, desde el punto de vista de la disciplina psicológica, el significado de psicólogas/os que trabajan en consultorios de atención primaria de salud (APS) sobre las IPG en el tratamiento de la depresión. Se entrevistaron a ocho psicólogas/os de los distintos Servicios de Salud de la Región Metropolitana de Santiago. Este estudio se basó en las premisas de la Teoría Fundamentada, utilizando sus estrategias de análisis. La categoría "los grupos no nos resultan" expone las principales barreras que impiden la realización de estas intervenciones. La carga laboral centrada en atenciones individuales, el escaso presupuesto destinado a su implementación, y la falta de instalaciones adecuadas para realizar las IPG emergen como barreras institucionales. Asi mismo, la "poca fe" en la efectividad del trabajo en grupo, la figura de las/os psicólogas/os como únicas/os profesionales capacitadas/os para trabajar con las emociones, la idea de que la baja adherencia al tratamiento no depende de su ejercicio laboral, y el hecho de que la implementación de las IPG dependa del interés individual de algunas/os profesionales, emergen como las principales resistencias profesionales a su realización. Se discuten los alcances de estas barreras, y se proponen soluciones que favorezcan el cambio cultural necesario para que las/los profesionales e instituciones de salud puedan alinearse en plenitud con el modelo comunitario de salud propuesto por el Plan Nacional de Salud Mental y Psiquiatría (PNSMP).

Investigaccion-accion en la sala de clases sobre las creencias de la cultura de la ciencia de un grupo de estudiantes universitarios y su relacion reciproca con el aprendizaje de las ciencias biologicas

NASA Astrophysics Data System (ADS)

Cordova-Santiago, Lizzette Astrid

La investigacion---accion que se llevo a cabo en la sala de clases tenia como punto de partida las creencias de la cultura de la ciencia de un grupo de estudiantes universitarios para luego examinar sus implicaciones en el proceso de aprendizaje de las Ciencias Biologicas. ¿Que se supone que hagan las creencias en relacion con el aprendizaje? ¿En que consiste incorporar este aspecto a la practica educativa universitaria? Utilizando el modelo de Kemmis y McTaggart (1987) la investigacion-accion se planteo como un proceso dinamico en cuatro momentos en espiral constituidos por la planificacion, la accion, la observacion y la reflexion. Cada una de las fases tuvo una intencion retrospectiva y prospectiva formando una espiral de autorreflexion del conocimiento y la accion. Se llevaron a cabo audio grabaciones en clases y analisis de documentos. Ademas, la profesora-investigadora hizo un portafolio para reflexionar sobre las creencias de la cultura de la ciencia que tienen los estudiantes y las creencias del aprendizaje que tiene la profesora y sobre como la comprension de estos elementos ayudo a mejorar su practica educativa a traves del tiempo. Los resultados obtenidos apuntan a que las creencias de la cultura de la ciencia que tiene el grupo de estudiantes son diversas. Ellos si creen que la ciencia tiene una cultura la cual describieron como: complicada y desconocida que evoluciona constantemente, que es un conjunto de metodos, que es altamente tecnologica, que resuelve problemas de salud, ayuda a interpretar la realidad del mundo que los rodea y su origen y que existen unas intersecciones entre la ciencia y el poder. Sobre las creencias del proceso de aprendizaje de la profesora-investigadora, estas senalan que el modelaje de actores, la vision de la academia que tiene ella asi como la participacion y negociacion entre todos los involucrados en el proceso educativo, son factores que inciden en el proceso de aprendizaje.

Variación temporal de las constantes fundamentales

NASA Astrophysics Data System (ADS)

Landau, S. J.; Vucetich, H.

La variación temporal de las constantes fundamentales es un problema que ha motivado numerosos trabajos teóricos y experimentales desde la hipótesis de los grandes números de Dirac en 1937. Entre los métodos experimentales y observacionales para establecer restricciones sobre la variación de las constantes fundamentes es importante mencionar: comparación entre relojes atómicos[1], métodos geofísicos[2][3], análisis de sistemas de absorción en quasares[4][5][6] y cotas provenientes de la nucleosíntesis primordial[7]. En un trabajo reciente[5], se reportó una significativa variación en la constante de estructura fina. Intentos de unificar las cuatro interacciones fundamentales dieron como resultado teorías con múltiples dimensiones como las teorías de Kaluza-Klein y teorías de supercuerdas. Estas teorías proporcionan un marco teórico natural para el estudio de la variación temporal de las constantes fundamentales. A su vez, un modelo sencillo para estudiar la variación de la constante de estructura fina, fue propuesto en [8], a partir de premisas muy generales como ser covarianza, invarianza de gauge, causalidad y invarianza ante reversiones temporales en el electromagnetismo. Diferentes versiones de las teorías antes mencionadas coinciden en predecir variaciones temporales de las constantes fundamentales pero difieren en la forma de esta variación[9][10]. De esta manera, las restricciones establecidas experimentalmente sobre la variación de las constantes fundamentales pueden ser una herramienta importante para testear estas diferentes teorías. En este trabajo, utilizamos las cotas provenientes de diversas técnicas experimentales, para testear si las mismas son consistentes con alguna de las teorías antes mencionadas. En particular, establecemos cotas sobre la variación de los parámentros libres de las diferentes teorías como por ejemplo el radio de las dimensiones extras en las teorías tipo Kaluza-Klein.

The Model of Optimization of Micro Energy; HOMER: El Modelo de Optimizacin de Micro energa (in Spanish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2004-05-01

HOMER, the model of optimization of micro energy, helps to disear systems out of the network and interconnected to the network. You can use HOMER to carry out the analysis to explore an extensive rank of questions of diseo. HOMER, el modelo de optimizacin de micro energa, le ayuda a disear sistemas fuera de la red e interconectados a la red. Usted puede usar HOMER para llevar a cabo el anlisis para explorar un amplio rango de preguntas de diseo.

Studies on magnetocaloric and magnetic coupling effects =

NASA Astrophysics Data System (ADS)

Amaral, Joao Cunha de Sequeira

O presente trabalho apresenta novas metodologias desenvolvidas para a analise das propriedades magneticas e magnetocaloricas de materiais, sustentadas em consideracoes teoricas a partir de modelos, nomeadamente a teoria de transicoes de fase de Landau, o modelo de campo medio molecular e a teoria de fenomeno critico. Sao propostos novos metodos de escala, permitindo a interpretacao de dados de magnetizacao de materiais numa perspectiva de campo medio molecular ou teoria de fenomeno critico. E apresentado um metodo de estimar a magnetizacao espontanea de um material ferromagnetico a partir de relacoes entropia/magnetizacao estabelecidas pelo modelo de campo medio molecular. A termodinamica das transicoes de fase magneticas de primeira ordem e estudada usando a teoria de Landau e de campo medio molecular (modelo de Bean-Rodbell), avaliando os efeitos de fenomenos fora de equilibrio e de condicoes de mistura de fase em estimativas do efeito magnetocalorico a partir de medidas magneticas. Efeitos de desordem, interpretados como uma distribuicao na interaccao magnetica entre ioes, estabelecem os efeitos de distribuicoes quimicas/estruturais nas propriedades magneticas e magnetocaloricas de materiais com transicoes de fase de segunda e de primeira ordem. O uso das metodologias apresentadas na interpretacao das propriedades magneticas de variados materiais ferromagneticos permitiu obter: 1) uma analise quantitativa da variacao de spin por iao Gadolinio devido a transicao estrutural do composto Gd5Si2Ge2, 2) a descricao da configuracao de cluster magnetico de ioes Mn na fase ferromagnetica em manganites da familia La-Sr e La-Ca, 3) a determinacao dos expoentes criticos β e δ do Niquel por metodos de escala, 4) a descricao do efeito da pressao nas propriedades magneticas e magnetocaloricas do composto LaFe11.5Si1.5 atraves do modelo de Bean-Rodbell, 5) uma estimativa da desordem em manganites ferromagneticas com transicoes de segunda e primeira ordem, 6) uma descricao de campo medio das propriedades magneticas da liga Fe23Cu77, 7) o estudo de efeitos de separacao de fase na familia de compostos La0.70-xErxSr0.30MnO3 e 8) a determinacao realista da variacao de entropia magnetica na familia de compostos de efeito magnetocalorico colossal Mn1-x-yFexCryAs.

Novas determinações dos parâmetros atmosféricos das estrelas anãs brancas DA

NASA Astrophysics Data System (ADS)

Giovannini, O.; Costa, A. F. M.; Kepler, S. O.

2003-08-01

Nós temos selecionado uma amostra de estrelas anãs brancas DA (atmosfera de hidrogênio) a partir dos índices de Strömgren cujos valores estão próximos a região de instabilidade das estrelas anãs brancas DA variáveis, as chamadas estrelas DAV ou ZZ Ceti. O objetivo é determinar os parâmetros fundamentais (temperatura efetiva, Teff, aceleração da gravidade, log g, e massa) destas estrelas para verificar quais os parâmetros estelares estão envolvidos com o mecanismo de pulsação das estrelas DAV. Nós obtemos, até agora, mais de 120 espectros óticos de estrelas DA. Entre as estrelas selecionadas há 20 estrelas variáveis (DAV). Assim, podemos verificar se existem ou não estrelas não variáveis dentro da faixa de instabilidade das estrelas ZZ Ceti. Neste trabalho nós apresentamos a determinação dos parâmetros atmosféricos (temperatura efetiva, Teff, e aceleração da gravidade, log g) das estrelas anãs brancas DA usando os novos modelos de atmosfera ML2/a = 0.6. Estes modelos têm sido utilizados recentemente por fornecerem uma excelente consistência interna na determinação das temperaturas nas regiões do ultra-violeta e ótico. Os parâmetros atmosféricos são determinados espectroscopicamente através da comparação do fluxo de energia das linhas de Balmer (Hb à H9) entre os espectros observados e sintéticos (gerados pelos modelos de atmosfera). As temperaturas obtidas com os novos modelos são, em geral, menores (~ 1000 K menos) que as temperaturas determinadas anteriormente, com modelos ML1. Os valores de log g não mudaram significativamente (menos de 10%). A faixa de instabilidade das DAVs está entre 11000 e 13000 K, consistente com dados de outros autores.

Differences in foot self-care and lifestyle between men and women with diabetes mellitus.

PubMed

Rossaneis, Mariana Angela; Haddad, Maria do Carmo Fernandez Lourenço; Mathias, Thaís Aidar de Freitas; Marcon, Sonia Silva

2016-08-15

to investigate differences with regard to foot self-care and lifestyle between men and women with diabetes mellitus. cross-sectional study conducted in a sample of 1,515 individuals with diabetes mellitus aged 40 years old or older. Poisson regression models were used to identity differences in foot self-care deficit and lifestyle between sexes, adjusting for socioeconomic and clinical characteristics, smoking and alcohol consumption. foot self-care deficit, characterized by not regularly drying between toes; not regularly checking feet; walking barefoot; poor hygiene and inappropriately trimmed nails, was significantly higher among men, though men presented a lower prevalence of feet scaling and use of inappropriate shoes when compared to women. With regard to lifestyle, men presented less healthy habits, such as not adhering to a proper diet and taking laboratory exams to check for lipid profile at the frequency recommended. the nursing team should take into account gender differences concerning foot self-care and lifestyle when implementing educational activities and interventions intended to decrease risk factors for foot ulceration. investigar as diferenças no autocuidado com os pés e no estilo de vida entre mulheres e homens diabéticos. estudo transversal realizado com uma amostra de 1.515 diabéticos com 40 anos ou mais. Foram utilizados modelos de regressão de Poisson para identificar diferenças entre os sexos na prevalência de déficit de autocuidado com os pés e no estilo de vida, ajustando-se por características socioeconômicas, clínicas, tabagismo e alcoolismo. a prevalência de déficit de autocuidado com os pés, caracterizada por baixa frequência de secagem dos espaços interdigitais; da não avaliação periódica dos pés; do hábito de andar descalço; de higiene insatisfatória e corte inadequado de unhas foi significativamente maior entre os homens. Contudo, eles apresentaram menor prevalência na prática de escaldar os pés e no uso de calçados inadequados em comparação às mulheres. Em relação ao estilo de vida, os homens também apresentaram comportamentos menos saudáveis pois tem significativamente menor controle alimentar e não realizam os exames laboratoriais referentes ao perfil lipídico na frequência recomendada. considerar as diferenças de gênero no autocuidado com os pés e no estilo de vida permite à equipe de enfermagem direcionar atividades educacionais e intervenções nos fatores de risco à ulceração dos pés. investigar las diferencias en el autocuidado de los pies y estilo de vida entre mujeres y hombres diabéticos. estudio transversal realizado con una muestra de 1.515 diabéticos con 40 años o más. Fueron utilizados los modelos de regresión de Poisson para identificar diferencias entre los sexos en la prevalencia de déficit de autocuidado de los pies y estilo de vida, ajustándolas por características socioeconómicas, clínicas, tabaquismo y alcoholismo. la prevalencia de déficit de autocuidado de los pies, caracterizada por: baja frecuencia de secado de los espacios interdigitales; falta de evaluación periódica de los pies; hábito de andar descalzo; higiene insatisfactoria; y, corte inadecuado de uñas, fue significativamente mayor entre los hombre. Sin embargo, estos presentaron menor prevalencia en la práctica de escaldar los pies y en el uso de calzados inadecuados en comparación a las mujeres. En relación al estilo de vida, los hombres también presentaron comportamientos menos saludables ya que tienen significativamente menor control alimentario y no realizan los exámenes de laboratorio referentes al perfil lipídico, con la frecuencia recomendada. considerar las diferencias de género en el autocuidado de los pies y en el estilo de vida, le permite al equipo de enfermería realizar actividades educacionales e intervenciones en los factores de riesgo para la ulceración de los pies.

Aging as a predictor of nursing workload in Intensive Care Unit: results from a Brazilian Sample.

PubMed

Ferretti-Rebustini, Renata Eloah de Lucena; Nogueira, Lilia de Souza; Silva, Rita de Cassia Gengo E; Poveda, Vanessa de Brito; Machado, Selma Pinheiro; Oliveira, Elaine Machado de; Andolhe, Rafaela; Padilha, Katia Grillo

2017-04-03

Verify if aging is an independent predictor of NW in ICU, according to age groups, and its predictive value as a determinant of NW in ICU. Study was conducted from 2012 to 2016. A convenience sample composed by patients (age ≥ 18) admitted to nine ICU belonging to a Brazilian hospital, was analyzed. Age was assumed as an independent variable and NW (measured by the Nursing Activities Score - NAS) as dependent. Linear regression model and ROC curve were used for the analysis. 890 participants (361 older people), mostly males (58.1%). The mean NAS score was higher among older participants in comparison to adults (p=0.004) but not within categories of aging (p=0.697). Age was responsible for 0.6% of NAS score. Each year of age increases NAS score in 0.081 points (p=0.015). However, age was not a good predictor of NAS score (AUC = 0.394; p=0.320). The care of older people in ICU is associated with an increase in NW, compared to adults. Aging can be considered an associated factor but not a good predictor of NW in ICU. Verificar si el envejecimiento es un predictor independiente de la Carga de Trabajo de Enfermería (CTE) en la Unidad de Cuidados Intensivos (UCI), según grupos etarios y su valor predictivo como determinante de la CTE en la UCI. Se analizó una muestra de conveniencia compuesta por pacientes (edad ≥ 18) ingresados en nueve UCI pertenecientes a un hospital brasileño. La edad se asumió como variable independiente y como variable dependiente la carga de trabajo de enfermería -medida por el sistema Nursing Activities Score (NAS) de puntuación de actividades de enfermería. Para el análisis, se utilizaron el modelo de regresión lineal y la curva ROC. 890 participantes (361 adultos mayores), en su mayoría varones (58,1%). La puntuación NAS promedio fue mayor entre los participantes adultos mayores en comparación con los adultos (p=0,004), pero no en las categorías de envejecimiento (p=0,697). La edad fue responsable del 0,6% de la puntuación NAS. Cada año de edad aumenta la puntuación NAS en 0,081 puntos (p=0,015). Sin embargo, la edad no resultó un buen predictor de la puntuación NAS (AbC=0,394; p=0,320). El cuidado de los adultos mayores en UCI se asocia con un aumento de la CTE en comparación con los adultos. El envejecimiento puede considerarse un factor asociado, pero no un buen predictor de la CTE en UCI.

Desenvolvimento de modelo clínico para predição da possibilidade de identificação da artéria de Adamkiewicz por angiotomografia

PubMed Central

Amato, Alexandre Campos Moraes; Parga, José Rodrigues; Stolf, Noedir Antônio Groppo

2018-01-01

Resumo Contexto Diferenças morfológicas da artéria de Adamkiewicz (AKA) entre a população portadora e não portadora de doença aórtica têm importância clínica, influenciando as complicações neuroisquêmicas da medula espinhal em procedimentos operatórios. Ainda não é conhecida a correlação entre parâmetros clínicos e a previsibilidade da identificação dessa artéria pela angiotomografia. Objetivo Desenvolver um modelo matemático que, através de parâmetros clínicos correlacionados com aterosclerose, possa prever a probabilidade de identificação da AKA em pacientes submetidos a angiotomografias. Método Estudo observacional transversal utilizando banco de imagens e dados de pacientes. Foi feita análise estatística multivariada e criado modelo matemático logit de predição para identificação da AKA. Variáveis significativas foram utilizadas na montagem da fórmula para cálculo da probabilidade de identificação. O modelo foi calibrado, e a discriminação foi avaliada pela curva receiver operating characteristic (ROC). A seleção das variáveis explanatórias foi guiada pela maior área na curva ROC (p = 0,041) e pela significância combinada das variáveis. Resultados Foram avaliados 110 casos (54,5% do sexo masculino, com idade média de 60,97 anos e etnia com coeficiente B -2,471, M -1,297, N -0,971), com AKA identificada em 60,9%. Índice de massa corporal: 27,06 ± 0,98 (coef. -0,101); fumantes: 55,5% (coef. -1,614/-1,439); diabéticos: 13,6%; hipertensos: 65,5% (coef. -1,469); dislipidêmicos: 58,2%; aneurisma aórtico: 38,2%; dissecção aórtica: 12,7%; e trombo mural: 24,5%. Constante de 6,262. Fórmula para cálculo da probabilidade de detecção: (e−(Coef. Etnia+(Coef. IMC×IMC)+Coef.fumante+Coef.HAS+Coef.dislip+Constante)+1)−1 . O modelo de predição foi criado e disponibilizado no link https://vascular.pro/aka-model . Conclusão Com as covariáveis etnia, índice de massa corporal, tabagismo, hipertensão arterial e dislipidemia, foi possível criar um modelo matemático de predição de identificação da AKA com significância combinada de nove coeficientes (p = 0,042). PMID:29930677

Incorporando a variabilidade no processo de identificação do modelo de máximo global no Grade of Membership (GoM): considerações metodológicas

PubMed Central

Guedes, Gilvan Ramalho; Siviero, Pamila Cristina Lima; Caetano, André Junqueira; Machado, Carla Jorge; Brondízio, Eduardo

2012-01-01

A disponibilidade de bases de dados cada vez mais complexas e multidimensionais é um dos principais motivadores para o aumento do número de estudos que utilizam análises multivariadas baseadas em lógica de conjuntos nebulosos. Apesar da disseminação do método Grade of Membership nos trabalhos empíricos brasileiros da área de ciências sociais e saúde, questões relativas à identificabilidade e estabilidade dos parâmetros finais estimados pelo programa GoM 3.4 não foram suficientemente aprofundadas. Dada a relevância de se obterem parâmetros únicos e estáveis, Guedes et al. (2010) propuseram um procedimento empírico para localizar um modelo de máximo global (MG) com parâmetros estáveis. Entretanto, seu localizador de MG não incorpora qualquer medida de variabilidade. Neste artigo, tal limitação é contornada por meio da utilização de uma estatística de ponderação – Máximo Global Ponderado (MGP) – semelhante ao coeficiente de variação. Esse indicador busca não penalizar de forma desproporcional situações nas quais os desvios médios, apesar de diferentes de zero, são muito pequenos. Apresentam-se evidências de que o localizador MGP reduz a distância do modelo identificado à real estrutura latente dos dados em análise, quando comparados ao modelo identificado pelo localizador não ponderado, MG. PMID:23293402

GIS-based hydrogeological databases and groundwater modelling

NASA Astrophysics Data System (ADS)

Gogu, Radu Constantin; Carabin, Guy; Hallet, Vincent; Peters, Valerie; Dassargues, Alain

2001-12-01

Reliability and validity of groundwater analysis strongly depend on the availability of large volumes of high-quality data. Putting all data into a coherent and logical structure supported by a computing environment helps ensure validity and availability and provides a powerful tool for hydrogeological studies. A hydrogeological geographic information system (GIS) database that offers facilities for groundwater-vulnerability analysis and hydrogeological modelling has been designed in Belgium for the Walloon region. Data from five river basins, chosen for their contrasting hydrogeological characteristics, have been included in the database, and a set of applications that have been developed now allow further advances. Interest is growing in the potential for integrating GIS technology and groundwater simulation models. A "loose-coupling" tool was created between the spatial-database scheme and the groundwater numerical model interface GMS (Groundwater Modelling System). Following time and spatial queries, the hydrogeological data stored in the database can be easily used within different groundwater numerical models. Résumé. La validité et la reproductibilité de l'analyse d'un aquifère dépend étroitement de la disponibilité de grandes quantités de données de très bonne qualité. Le fait de mettre toutes les données dans une structure cohérente et logique soutenue par les logiciels nécessaires aide à assurer la validité et la disponibilité et fournit un outil puissant pour les études hydrogéologiques. Une base de données pour un système d'information géographique (SIG) hydrogéologique qui offre toutes les facilités pour l'analyse de la vulnérabilité des eaux souterraines et la modélisation hydrogéologique a été établi en Belgique pour la région Wallonne. Les données de cinq bassins de rivières, choisis pour leurs caractéristiques hydrogéologiques différentes, ont été introduites dans la base de données, et un ensemble d'applications qui ont été développées permet dès maintenant de prochaines avancées. L'intérêt grandit pour le potentiel d'intégration de la technologie des SIG et les modèles de simulation des nappes. Un outil de couplage a été créé entre le schéma de base de données spatiales et l'interface GMS (GroundWater Modelling System, système de modélisation de nappe) du modèle numérique de nappe. Suivant les requêtes en fonction du temps et de l'espace, les données hydrogéologiques stockées dans la base de données peuvent être aisément utilisées dans différents modèles numériques de nappes. Resumen. La fiabilidad y validez de los análisis de aguas subterráneas dependen enormemente de la disponibilidad de muchos datos de alta calidad. Integrarlos en una estructura consistente y lógica mediante un entorno informático sirve para asegurar su validez y disponibilidad, y rrepresenta una herramienta muy potente para ulteriores estudios hidrogeológicos. Se ha diseñado en la región de Valonia (Bélgica) una base de datos hidrogeológica basada en un sistema de información geográfica (GIS), con el que se dispone de útiles para elaborar análisis de vulnerabilidad y modelos hidregeológicos. Se ha utilizado datos de cinco cuencas fluviales, elegidas por sus características hidrogeológicas contrastadas, así como un conjunto de aplicaciones desarrolladas con vistas al futuro. El interés por el potencial que ofrece la integración de la tecnología GIS y los modelos de simulación de aguas subterráneas está en auge. Se ha desarrollado un "emulador" que integra el esquema espacial de la base de datos y la interfaz GMS (GroundWater Modelling System) de modelación numérica de aguas subterráneas. A partir de búsquedas temporales y espaciales, los datos hidrogeológicos almacenados en la base de datos pueden ser utilizados fácilmente en modelos numéricos diferentes de aguas subterráneas.

Sustainable development and management of an aquifer system in western Turkey

NASA Astrophysics Data System (ADS)

Sakiyan, Jale; Yazicigil, Hasan

This study presents the establishment of sustainable development and management policies for the Küçük Menderes River Basin aquifer system in western Turkey. Geological, hydrogeological, and geophysical data are used conjunctively to define various hydrogeological units and their geometry. Distributions of hydraulic-parameter values and recharge are estimated by geostatistical methods and hydrologic simulations, respectively. A finite-difference groundwater flow model is used to represent the unconfined flow in the aquifer system. The model has been calibrated under steady state and transient conditions. The resulting model was used to test seven management scenarios for a planning period of 21 years to determine the so-called safe yield and sustainable yield of the aquifer system and to investigate the potential impacts of four planned surface water reservoirs on groundwater resources in the basin. The results demonstrate that the continuation of the present pumping rates exceeds both the safe yield and the sustainable yield of the aquifer system. Consequently, the growing need for irrigation water should be met by the construction of the planned surface water reservoirs and the implementation of efficient water management policies and plans. Cette étude présente la proposition d'une politique de développement et de gestion durables du système aquifère du bassin du Petit Mendérès dans l'ouest de la Turquie. Des données géologiques, hydrogéologiques et géophysiques ont été utilisées conjointement pour définir les différentes unités hydrogéologiques et leur géométrie. Les distributions des paramètres hydrauliques et de la recharge ont été estimées respectivement par des méthodes géostatistiques et des simulations hydrologiques. Un modèle d'écoulement souterrain aux éléments finis a été utilisé pour représenter l'écoulement non captif dans le système aquifère. Le modèle a été calibré dans des conditions de régimes permanent et transitoire. Le modèle résultant a servi à tester sept scénarios de gestion pour une période de programmation de 21 ans, afin de déterminer les débits de prélèvement sûr et durable dans le système aquifère et d'étudier les impacts potentiels de quatre réservoirs d'eau de surface en projet sur les eaux souterraines du bassin. Les résultats montrent que la poursuite des prélèvements au débit actuel excède aussi bien le débit d'exploitation de sécurité que celui durable pour le système aquifère. Par conséquent, les besoins croissants d'eau pour l'irrigation doivent être satisfaits par la construction des réservoirs projetés et par la mise en place de politiques et de plans de gestion de l'eau efficace. Este estudio presenta el establecimiento de políticas sustentables de desarrollo y gestión en el sistema acuífero de la cuenca del río Küçük Menderes, al Oeste de Turquía, para lo que se ha utilizado datos geológicos, hidrogeológicos y geofísicos de forma conjunta de cara a definir diversas unidades hidrogeológicas y su geometría. La distribución de los parámetros hidráulicos y de la recarga ha sido estimada mediante métodos geoestadísticos y simulaciones hidrológicas, respectivamente. Se ha empleado un modelo de las aguas subterráneas en diferencias finitas para representar el flujo no confinado en el sistema acuífero, el cual se ha calibrado bajo condiciones estacionarias y transitorias. El modelo resultante ha sido usado para contrastar siete escenarios de gestión durante un período de planificación de 21 años con el fin de determinar el punto de explotación segura y sustentable del sistema acuífero, así como para investigar los impactos potenciales sobre los recursos subterráneos de los cuatro embalses superficiales que se hallan en proyecto. Los resultados demuestran que el mantenimiento de las tasas actuales de extracción del acuífero supera tanto el régimen de bombeo seguro como el sustentable del sistema. Por consiguiente, se debería compensar la necesidad creciente de agua para riego con la construcción de los reservorios superficiales previstos y con la implementación de políticas y planes de gestión eficiente del agua.

Karst groundwater: a challenge for new resources

NASA Astrophysics Data System (ADS)

Bakalowicz, Michel

2005-03-01

Karst aquifers have complex and original characteristics which make them very different from other aquifers: high heterogeneity created and organised by groundwater flow; large voids, high flow velocities up to several hundreds of m/h, high flow rate springs up to some tens of m3/s. Different conceptual models, known from the literature, attempt to take into account all these particularities. The study methods used in classical hydrogeology—bore hole, pumping test and distributed models—are generally invalid and unsuccessful in karst aquifers, because the results cannot be extended to the whole aquifer nor to some parts, as is done in non-karst aquifers. Presently, karst hydrogeologists use a specific investigation methodology (described here), which is comparable to that used in surface hydrology. Important points remain unsolved. Some of them are related to fundamental aspects suc h as the void structure - only a conduit network, or a conduit network plus a porous matrix -, the functioning - threshold effects and non-linearities -, the modeling of the functioning - double or triple porosity, or viscous flow in conduits - and of karst genesis. Some other points deal with practical aspects, such as the assessment of aquifer storage capacity or vulnerability, or the prediction of the location of highly productive zones. Los acuíferos kársticos tienen características originales y complejas que los hacen muy diferentes de otros acuíferos: alta heterogeneidad creada y organizada por el flujo de agua subterránea, espacios grandes, velocidades altas de flujo de hasta varios cientos de m/h, manantiales con ritmo alto de flujo de hasta algunas decenas de m3/s. Diferentes modelos conceptuales que se conocen en la literatura tratan de tomar en cuenta todas estas particularidades. Los métodos de estudio usados en hidrogeología clásica- pozos, pruebas de bombeo y modelos distribuidos- son generalmente inválidos y no exitosos en acuíferos kársticos, debido a que los resultados no pueden extenderse a todo el acuífero ni a alguna de sus partes, como se hace en acuíferos no kársticos. Actualmente los hidrogeólogos kársticos usan una metodología de investigación específica, que se des cribe aquí, la cual es comparable con la que se utiliza en hidrología superficial. Puntos importantes permanecen sin resolverse. Algunos de ellos se relacionan con aspectos fundamentales tal como la estructura de espacios- solo una red de conductos, ouna red de conductos más una matriz porosa-, el funcionamiento-efectos threshold y no-linealidades-, el modelizado del funcionamiento-porosidad dobleo triple, o flujo viscoso en conductos- y génesis del karst. Algunos otros puntos se relacionan con aspectos prácticos, tal como la evaluación de la capacidad de almacenamiento del acuífero o la vulnerabilidad, o la predicción de la localización de zonas altamente productivas. Les aquifères karstiques présentent des caractères originaux complexes qui les distinguent profondément de tous les autres milieux aquifères: forte hétérogénéité créée et organisée par les écoulements souterrains eux-mêmes, vides de très grandes dimensions, vitesses d'écoulement pouvant atteindre quelques centaines de mètres par heure, sources à débit pouvant atteindre quelques dizaines de m3/s. Différents modèles conceptuels tentent de prendre en compte ces particularités. Les méthodes d'étude de l'hydrogéologie classique—forage, essai de pompage et modèles maillés - ne sont en général pas adaptés aux aquifères karstiques, parce que les résultats obtenus ne peuvent pas être étendus à l'aquifère tout entier, ou à certaines de ses parties, comme cela est fait pour les aquifères non karstiques. Actuellement les hydrogéologues du karst ont recours à une méthodologie d'étude spécifique décrite ici, comparable à celle utilisée en hydrologie de surface. Des points importants restent à résoudre. Certains concernent des aspects fondamentaux, comme la structure des vides - réseau de conduits uniquement, ou bien réseau de conduits et matrice poreuse -, le fonctionnement - problèmes de seuil et plus généralement les non-linéarités -, la modélisation du fonctionnement - double porosité ou écoulement visqueux en conduits - et de la genèse du karst. D'autres points portent sur des aspects pratiques, comme l'évaluation de la capacité de stockage ou de la vulnérabilité de l'aquifère, et la prédiction des zones à haute productivité.

Measurement of Family-centered care perception and parental stress in a neonatal unit.

PubMed

Balbino, Flávia Simphronio; Balieiro, Maria Magda Ferreira Gomes; Mandetta, Myriam Aparecida

2016-08-08

to evaluate the effects of the implementation of the Patient and Family-Centered Care Model on parents and healthcare perceptions and parental stress. a quasi-experimental study developed in a neonatal unit of a university hospital in the municipality of São Paulo, Brazil, with the implementation of this model of care. Data collection were performed by two sample groups, one using non-equivalent groups of parents, and another using equivalent groups of healthcare professionals. The instruments Perceptions of Family-Centered Care-Parent Brazilian Version, Perceptions of Family-Centered Care-Staff Brazilian Version and Parental Stress Scale: Neonatal Intensive Care Unit, were applied to 132 parents of newborns hospitalized and to 57 professionals. there was a statistically significant improvement in the perceptions of the parents in most items assessed (p ≤0,05) and for the staff in relation to the family welcome in the neonatal unit (p = 0.041) and to the comprehension of the family's experience with the infant´s hospitalization (p = 0,050). There was a reduction in the average scores of parental stress, with a greater decrease in the Alteration in Parental Role from 4,2 to 3,8 (p = 0,048). the interventions improved the perceptions of parents and healthcare team related to patient and family-centered care and contributed to reducing parental stress. avaliar os efeitos da implementação do Modelo do Cuidado Centrado no Paciente e Família na percepção de pais e profissionais de saúde e no estresse parental. Estudo quase experimental com grupos não equivalentes para avaliação dos efeitos da intervenção na percepção de pais; e com grupos equivalentes para a avaliação na percepção de profissionais de saúde, desenvolvido na unidade neonatal de um hospital universitário do município de São Paulo. Os instrumentos, Percepção do Cuidado Centrado na Família- Pais versão brasileira, Percepção do Cuidado Centrado na Família- Equipe versão brasileira e Parental Stress Scale: Neonatal Intensive Care Unit, foram aplicados com 132 pais de recém-nascidos internados e 57 profissionais da equipe. houve melhora estatisticamente significante na percepção dos pais na maioria dos itens avaliados (p≤0,05) e para os profissionais em relação ao acolhimento da família na unidade neonatal (p= 0,041) e a compreensão da vivência da família com a hospitalização (p=0,050). Houve redução dos escores médios do estresse parental, com maior queda na Alteração do Papel de Pais de 4,2 para 3,8 (p=0,048). as intervenções realizadas melhoraram a percepção de pais e de profissionais da equipe de saúde sobre o Cuidado Centrado no Paciente e Família e contribuíram para a redução do estresse parental. evaluar los efectos de la implementación del Modelo del Cuidado Centrado en el Paciente y la Familia en la percepción de los padres y profesionales de la salud y en lo estrés parental. estudio cuasi-experimental con grupos no equivalentes para evaluar los efectos de la intervención en la percepción de los padres; y grupos equivalentes para evaluar la percepción de los profesionales de la salud, desarrollado en la unidad neonatal de un hospital universitario en el municipio de Sao Paulo. Los instrumentos de Percepción del Cuidado Centrado en el Paciente y la Familia- Padres versión brasileña, Percepción del Cuidado Centrado en el Paciente y la Familia-Equipo versión brasileña y Parental Stress Scale: Neonatal Intensive Care Unit, se aplicaron a 132 padres de los recién nacidos hospitalizados y 57 profesional del equipo. se observó una mejoría estadísticamente significativa en la percepción de los padres en la mayoría de los ítems evaluados (p = 0,05) y para los profesionales en relación con el cuidado de la familia en la unidad neonatal (p = 0,041) y la comprensión de la experiencia de la familia con la hospitalización (p = 0,050). Hubo una reducción en las puntuaciones medias de estrés de los padres, con una mayor disminución en la Alteración del Rol Parental 4.2 a 3.8 (p = 0,048). las intervenciones mejoran la percepción de los padres y los profesionales del equipo de salud en el Cuidado Centrado en el Paciente y la Familia y ha contribuido a reducir el estrés de los padres.

Uso de modelos mecânicos em curso informal de astronomia para deficientes visuais. Resgate de uma experiência

NASA Astrophysics Data System (ADS)

Tavares, E. T., Jr.; Klafke, J. C.

2003-08-01

O presente trabalho propõe-se a resgatar uma experiência que teve lugar no Planetário de São Paulo nos anos 60. Em 1962, o Sr. Acácio, então com 37 anos, deficiente visual desde os 27, passou a assistir às aulas ministradas pelo Prof. Aristóteles Orsini aos integrantes do corpo de servidores do Planetário. O Sr. Acácio era o único deficiente da turma e, embora possuísse conhecimentos básicos e relativamente avançados de matemática, enfrentava dificuldades na compreensão e acompanhamento da exposição, como também em estudos posteriores. Com o intuito de auxiliá-lo na superação desses problemas, o Prof. Orsini solicitou a construção de modelos mecânicos que, através do sentido do tato, permitissem o acompanhamento das aulas e a transposição do modelo para o "constructo" mental. Essa prática mostrou-se tão eficaz que facilitou sobejamente o aprendizado da matéria pelo sujeito. O Sr. Acácio passou a integrar o corpo de professores do Planetário/Escola Municipal de Astrofísica, tendo ficado responsável pelo curso de "Introdução à Astronomia" por vários anos. Além disso, a experiência foi tão bem sucedida que alguns dos modelos tiveram seus elementos constitutivos pintados diferencialmente para serem utilizados em cursos regulares do Planetário, tornando-se parte integrante do conjunto de recursos didáticos da instituição. É pensando nessa eficácia, tanto em seu objetivo original permitir o aprendizado de um deficiente visual quanto no subsidiário recurso didático sistemático da instituição que decidimos resgatar essa experiência. Estribados nela, acreditamos ser extremamente produtivo, em termos educacionais, o aperfeiçoamento dos modelos originais, agora resgatados e restaurados, e a criação de outros que pudessem ser utilizados no ensino dessa ciência a deficientes visuais.

What is (and Isn't) Wrong with Both the Tension and Shear Failure Models for the Formation of Lineae on Europa

NASA Technical Reports Server (NTRS)

Kattenhorn, S. A.

2004-01-01

An unresolved problem in the interpretation of lineae on Europa is whether they formed as tension- or shear-fractures. Voyager image analyses led to hypotheses that Europan lineaments are tension cracks induced by tidal deformation of the ice crust. This interpretation continued with Galileo image analyses, with lineae being classified as crust- penetrating tension cracks. Tension fracturing has also been an implicit assumption of nonsynchronous rotation (NSR) studies. However, recent hypotheses invoke shear failure to explain lineae development. If a shear failure mechanism is correct, it will be necessary to re-evaluate any models for the evolution of Europa's crust that are based on tensile failure models, such as NSR estimates. For this reason, it is imperative that the mechanism by which fractures are initiated on Europa be unambiguously unraveled. A logical starting point is an evaluation of the pros and cons of each failure model, highlighting the lines of evidence that are needed to fully justify either model.

What InSAR time-series methods are best suited for the Ecuadorian volcanoes

NASA Astrophysics Data System (ADS)

Mirzaee, S.; Amelung, F.

2017-12-01

Ground displacement measurements from stacks of SAR images obtained using interferometric time-series approaches play an increasingly important role for volcanic hazard assessment. The inflation of the ground surface can indicate that magma ascends to shallower levels and that a volcano gets ready for an eruption. Commonly used InSAR time-series approaches include Small Baseline (SB), Persistent Scatter InSAR (PSI) and SqueeSAR methods but it remains unclear which approach is best suited for volcanic environments. On this poster we present InSAR deformation measurements for the active volcanoes of Ecuador (Cotopaxi, Tungurahua and Pichincha) using a variety of INSAR time-series methods. We discuss the pros and cons of each method given the available data stacks (TerraSAR-X, Cosmo-Skymed and Sentinel-1) in an effort to design a comprehensive observation strategy for the Ecuadorian volcanoes. SAR data are provided in the framework of the Group on Earth Observation's Ecuadorian Volcano Geohazard Supersite.

Estudio de la influencia de la refrigeracion con aire de forma natural e inducida en el comportamiento de instalaciones fotovoltaicas

NASA Astrophysics Data System (ADS)

Mazon Hernandez, Rocio

The aim is to analyse the negative influence of high panel temperatures on electrical production when they are placed on steel roofs of industrial buildings and greenhouse roofs. Different configurations have been tested in order to allow cooling of photovoltaic panels to decrease panel temperature and improve electrical performance. To research this problem two experimental facilities have been built. The first facility includes two panels fixed on a structure. A panel is integrated on a parallel steel plate which does not allow sufficient cooling. Between both surfaces, there is an open air channel in which an air flow is created by the chimney effect thus cooling the panel by natural convection or inducing air, using a fan, by forced convection. The other panel has not any plate underneath it and is used as a referent. The electrical behaviour of the integrated panel has been studied for different air gaps and induced velocities, being also compared with the reference panel. An experimental model was developed to establish correlations which allow determine the panel temperature depending on the influential variables on the cooling ability. This research also analyses the data of a working solar plant, with the same panel model, obtaining the correlations between electrical variables and panel temperature. A comparison with the electrical behaviour in the experimental facility and the solar plant is also presented. The second experimental facility is a replica of a photovoltaic greenhouse. It consists of four photovoltaic panels placed on the plastic roof, providing an open and divergent channel between both surfaces thus creating an air flow by natural convection. This research studies the effect of high temperatures within the greenhouse which is transferred by the roof and thus affects the electrical production. In addition, two air gaps were used and the effect of adding insulating material to the plastic roof was studied. The electrical variables of the panels are analysed to compare and select the best configuration. The presented research provides a deep knowledge of how they work as well as information and results for an improvement in future designs of building integrated photovoltaic systems. Este estudio se centra en analizar la influencia negativa de la temperatura en la produccion electrica de paneles fotovoltaicos al estar emplazados sobre cubierta de acero, como sucede en naves industriales y sobre un invernadero. Se estudian diferentes configuraciones que permitan refrigerar los paneles, reduciendo su temperatura y mejorar su rendimiento. Para abordar este problema, se han construido dos instalaciones experimentales, fieles a plantas solares en funcionamiento. Una instalacion engloba dos paneles fotovoltaicos sobre estructura fija al suelo. Uno de los paneles esta integrado sobre una superficie paralela y metalica. Entre ambas superficies existe un espacio que posibilita circular aire, permitiendo refrigerar el panel por conveccion natural, o conveccion forzada impulsando el aire con un ventilador. El otro panel, libre por su cara posterior y se ha considerado de referencia. Se ha estudiado el comportamiento del panel integrado sobre cubierta para diferentes secciones de aire y velocidades inducidas, comparandolo con el panel de referencia. Se ha desarrollado un modelo experimental que nos permite determinar la temperatura del panel en funcion de las variables que influyen en su refrigeracion. Adicionalmente, se han analizado los datos de una planta solar en funcionamiento, con paneles de igual caracteristicas, obteniendo correlaciones entre la temperatura del panel y las variables electricas y comparandolos con las obtenidas en la instalacion experimental. La segunda instalacion experimental reproduce parte de una instalacion solar sobre un invernadero, formada por cuatro paneles fotovoltaicos colocados sobre el plastico del invernadero, existiendo un canal divergente entre ambas superficies. Se estudia la influencia de las altas temperaturas en el interior del invernadero sobre la produccion electrica de los paneles, decido a la transferencia de calor del interior del invernadero. Ademas, se han ensayado dos separaciones diferentes y para cada una se ha comparado con la misma, utilizando un aislante sobre la cubierta. El estudio realizado sobre ambas instalaciones ha proporcionado un conocimiento profundo del funcionamiento de cada una de ellas, asi como informacion valida para una mejora de futuros disenos de instalaciones fotovoltaicas sobre cubiertas.

Direct comparison of polymethylmetacrylate (PMMA) and silicone-on-glass (SOG) for Fresnel lenses in concentrating photovoltaics (CPV)

NASA Astrophysics Data System (ADS)

Annen, Hans Philipp; Fu, Ling; Leutz, Ralf; González, Luis; Mbakop, Jehu

2011-09-01

The CPV community is still undecided on one critical issue: what material to use best for Fresnel lens parquets. Reliability and longevity are the most important, but all other properties play roles as well. We have developed and manufactured Fresnel lenses with the two commonly used materials: PMMA (Polymethylmethacrylate) and silicone on glass (SOG). Both lenses are designed for the same optical train for best comparability. This allows for better understanding the pros and cons of the materials and making an informed choice for a specific CPV module. While PMMA lenses are embossed from pre-fab sheets in a hot-cold process, the silicone lenses are cast from a heat-curing silicone rubber at moderate temperatures, reducing the energy consumption. PMMA allows for the inclusion of custom low-profile 3D (2.5D) structures for module assembly and mechanical alignment, a feature not possible in silicone due to its low rigidity. Both lenses suffer from thermal expansion and refractive index change. While PMMA parquets expand isotropically, SOG prisms deform due to the difference of expansion coefficients between the glass and the silicone. SOG lenses are prone to delamination of the silicone film. The adhesive strength of the film to the glass can be measured using a modified blister test that we developed. The results show large difference with different materials and confirm the necessity of controlling this issue closely. While the small thermal expansion of the glass sheets allows for larger parquet sizes, the deformation of the prisms with temperature may cause a performance hit.

Comparison of Reconstruction and Control algorithms on the ESO end-to-end simulator OCTOPUS

NASA Astrophysics Data System (ADS)

Montilla, I.; Béchet, C.; Lelouarn, M.; Correia, C.; Tallon, M.; Reyes, M.; Thiébaut, É.

Extremely Large Telescopes are very challenging concerning their Adaptive Optics requirements. Their diameters, the specifications demanded by the science for which they are being designed for, and the planned use of Extreme Adaptive Optics systems, imply a huge increment in the number of degrees of freedom in the deformable mirrors. It is necessary to study new reconstruction algorithms to implement the real time control in Adaptive Optics at the required speed. We have studied the performance, applied to the case of the European ELT, of three different algorithms: the matrix-vector multiplication (MVM) algorithm, considered as a reference; the Fractal Iterative Method (FrIM); and the Fourier Transform Reconstructor (FTR). The algorithms have been tested on ESO's OCTOPUS software, which simulates the atmosphere, the deformable mirror, the sensor and the closed-loop control. The MVM is the default reconstruction and control method implemented in OCTOPUS, but it scales in O(N2) operations per loop so it is not considered as a fast algorithm for wave-front reconstruction and control on an Extremely Large Telescope. The two other methods are the fast algorithms studied in the E-ELT Design Study. The performance, as well as their response in the presence of noise and with various atmospheric conditions, has been compared using a Single Conjugate Adaptive Optics configuration for a 42 m diameter ELT, with a total amount of 5402 actuators. Those comparisons made on a common simulator allow to enhance the pros and cons of the various methods, and give us a better understanding of the type of reconstruction algorithm that an ELT demands.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meats, A.

Both wild and released (sterile) Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) and wild Bactrocera papayae (Drew and Hancock) in Australia had patchy distributions and comparisons with predictions of the negative binomial model indicated that the degree of clumping was sometimes very high, particularly at low densities during eradication. An increase of mean recapture rate of sterile B. tryoni on either of 2 trap arrays was not accompanied by a reduction in its coefficient of variation and when recapture rates were high, the percentage of traps catching zero decreased only slightly with increase in recapture rate, indicating that it is not practicablemore » to decrease the heterogeneity of dispersion of sterile flies by increasing the number released. There was often a mismatch between the dispersion patterns of the wild and sterile flies, and the implications of this for the efficiency of the sterile insect technique (SIT) were investigated with a simulation study with the observed degrees of mismatch obtained from the monitoring data and assuming the overall ratio of sterile to wild flies to be 100:1. The simulation indicated that mismatches could result in the imposed rate of increase of wild flies being up to 3.5 times higher than that intended (i.e., 0.35 instead of 0.1). The effect of a mismatch always reduces the efficiency of SIT. The reason for this asymmetry is discussed and a comparison made with host-parasitoid and other systems. A release strategy to counter this effect is suggested. (author) [Spanish] Las moscas naturales y liberadas (esteriles) de Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) y Bactrocera papayae (Drew and Hancock) en Australia tuvieron distribuciones en parches y sus compariciones con las predicciones de un modelo binomial negativo indicaron un nivel de agregacion a veces fue muy alto, particularmente en las densidades bajas durante de eradicacion. Un aumento en el promedio de la tasa de B. tryoni esteriles recapturadas en las dos formas de trampas no fue acompanado por una reduccion en su coeficiente de variacion y cuando las tasas de moscas recapturadas fue alto, el porcentaje de las trampas que capturaron ninguna mosca bajo solo un poco con un aumento en la tasa de las moscas recapturadas, esto indico que no es practicable bajar la heterogenicidad de dispersion de las moscas esteriles por medio de un aumento el numero de moscas liberadas. Muy a menudo se encontro un desajusto entre los patrones de dispersion de las moscas naturales y esteriles, y las implicaciones de esto para la eficiencia de la tecnica del insecto esteril (TIE) fueron investigadas en un estudio de simulacion con los grados de desajustes observados obtenidos de los datos del monitoreo y se considero que la razon general del numero de moscas esteriles a moscas naturales fueron 100:1. La simulacion indico que los desajustes en los patrones de dispersion pueden resultar en una tasa impuesta sobre el aumento de las moscas naturales de hasta 3.5 veces mas alta que la tasa intentada (i.e., 0.35 en vez de 0.1). El efecto de un desajuste siempre reduce la eficiencia de TIS. Se discute la razon para esta asimetria y una comparicion hecha con el sistema de hospedero-parasitoid y otros sistemas. Se sugiere una estrategia de liberacion para contrarrestar este efecto. (author)« less

Physiological adaptation of maternal plasma volume during pregnancy: a systematic review and meta-analysis.

PubMed

de Haas, S; Ghossein-Doha, C; van Kuijk, S M J; van Drongelen, J; Spaanderman, M E A

2017-02-01

To describe the physiological pattern of gestational plasma volume adjustments in normal singleton pregnancy and compare this with the pattern in pregnancies complicated by pregnancy-induced hypertension, pre-eclampsia or fetal growth restriction. We performed a meta-analysis of the current literature on plasma volume adjustments during physiological and complicated pregnancies. Literature was retrieved from PubMed (NCBI) and EMBASE (Ovid) databases. Included studies reported both reference plasma volume measurements (non-pregnant, prepregnancy or postpartum) and measurements obtained during predetermined gestational ages. Mean differences bet ween the reference and pregnancy plasma volume measurements were calculated for predefined intervals of gestational age using a random-effects model described by DerSimonian and Laird. Thirty studies were included in the meta-analysis with publication dates ranging from 1934 to 2007. Plasma volume increased in the first weeks of pregnancy, with the steepest increase occurring during the second trimester. Plasma volume continued to increase in the third trimester with a pooled maximum increase of 1.13 L (95% CI, 1.07-1.19 L), an increase of 45.6% (95% CI, 43.0-48.1%) in physiological pregnancies compared with the reference value. The plasma volume expansion in gestational hypertensive and growth-restricted pregnancies was 0.80 L (95% CI, 0.59-1.02 L), an increase of 32.3% (95% CI, 23.6-41.1%) in the third trimester, a smaller increase than in physiological pregnancies (P < 0.0001). During physiological pregnancy, plasma volume increases by, on average, more than 1 L as compared with non-pregnant conditions. In pregnancies complicated by pregnancy-induced hypertension, pre-eclampsia or fetal growth restriction, plasma volume increase in the third trimester is 13.3% lower than in normal pregnancy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Adaptación fisiológica del volumen del plasma materno durante el embarazo: una revisi\\xF3n sistemática y metaanálisis RESUMEN OBJETIVO: Describir el patrón fisiológico de los cambios en el volumen del plasma gestacional en embarazos normales con feto único y compararlo con el patrón en los embarazos complicados por hipertensión gestacional, preeclampsia o restricción del crecimiento fetal. MÉTODOS: Se realizó un metaanálisis de la literatura actual sobre los cambios en el volumen de plasma durante embarazos complicados y fisiológicos. La literatura se obtuvo de las bases de datos PubMed (NCBI) y EMBASE (Ovid). Los estudios incluidos mencionaban tanto mediciones de referencia del volumen plasmático (no embarazada, antes del embarazo o después del parto) como mediciones tomadas a edades gestacionales predeterminadas. Se calcularon las medias de las diferencias entre las mediciones de referencia y las del embarazo para el volumen plasmático a intervalos predefinidos de la edad gestacional, utilizando un modelo de efectos aleatorios descrito por DerSimonian y Laird. En el metaanálisis se incluyeron treinta estudios con fechas de publicación entre 1934 y 2007. El volumen plasmático aumentó en las primeras semanas de embarazo y el mayor incremento se produjo durante el segundo trimestre. El volumen de plasma continuó aumentando en el tercer trimestre con un aumento combinado máximo de 1,13L (IC 95%, 1,7-1,19 L), lo que supone un aumento del 45,6% (IC 95%, 43,0-48,1%) en embarazos fisiológicas en comparación con el valor de referencia. El aumento del volumen plasmático en los embarazos con hipertensión y con crecimiento intrauterino restringido fue de 0,80L (IC 95%, 0,59-1,02 L), lo que supone un aumento del 32,3% (IC 95%, 23,6-41,1%) en el tercer trimestre, y un incremento menor que en los embarazos fisiológicos (P <0,0001). Durante el embarazo fisiológico el volumen de plasma aumenta, en promedio, más de 1L, en comparación con el de las no embarazadas. En los embarazos complicados por hipertensión gestacional, preeclampsia o restricción del crecimiento fetal, el aumento del volumen plasmático en el tercer trimestre es un 13,3% menor que en el embarazo normal. :meta : ,、。 : meta。PubMed(NCBI)EMBASE(Ovid)。(、)。DerSimonianLaird,。 : Meta30,19342007。,。,1.13 L(95% CI,1.07~1.19 L),,45.6%(95% CI,43.0%~48.1%)。0.80 L(95%CI,0.59~1.02 L),32.3%(95% CI,23.6%~41.1%),(P<0.0001)。 : ,,1 L。、,13.3%。. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

La preparacion en ciencia de los candidatos a maestros del nivel elemental primario segun la reforma de la educacion cientifica en Puerto Rico: Una propuesta de secuencia curricular

NASA Astrophysics Data System (ADS)

Rodriguez Plaza, Evelyn

El proposito de esta investigacion fue identificar los componentes de la preparacion en ciencia que deben recibir los estudiantes del Bachillerato en Artes en Educacion Elemental, Nivel Primario, de acuerdo a los documentos que dirigen la reforma de la educacion cientifica en Puerto Rico. Tambien, se identificaron los componentes de los cursos que forman parte de la preparacion en ciencia de estos estudiantes. Se compararon los componentes de la preparacion en ciencia y los componentes de los cursos para determinar congruencias y discrepancias. Con los datos recopilados se identificaron los componentes de los cursos de una secuencia curricular para la preparacion en ciencia de los candidatos a maestros del nivel elemental primario. La secuencia curricular que se propone en esta investigacion incluye cursos de contenido cientifico y de metodologia en la ensenanza de la ciencia disenados para satisfacer las necesidades de los candidatos. Se recomienda que en los procesos para el diseno, la implantacion y la evaluacion de estos cursos participen profesores de ciencia, profesores de educacion y maestros del nivel elemental primario. Todos los cursos de la secuencia curricular deben tener un enfoque constructivista. Las experiencias educativas que se incluyan en los cursos deben aspirar a desarrollar en los candidatos los atributos de la cultura cientifica y actitudes positivas hacia la ciencia y hacia la ensenanza de esta disciplina. El modelaje por parte de los profesores que ensenen los cursos de la secuencia curricular es fundamental en el desarrollo profesional de los candidatos. Se recomienda que en los cursos de contenido cientifico se estudien los conceptos y los conocimientos cientificos que forman parte del curriculo de Kindergarten a tercer grado de forma integrada y con una profundidad universitaria. Estos cursos deben tener un enfoque interdisciplinario e incluir el estudio de la naturaleza de la ciencia y un componente de laboratorio para desarrollar los procesos de la ciencia y las destrezas de la investigacion cientifica. En los cursos de metodologia en la ensenanza de la ciencia se deben estudiar los modelos, los metodos, las estrategias y las tecnicas mas efectivas para la ensenanza y el aprendizaje de la ciencia, asi como las tecnicas de avaluacion.

Life-cycle optimization model for distributed generation in buildings

NASA Astrophysics Data System (ADS)

Safaei, Amir

O setor da construcao e responsavel por uma grande parte do consumo de energia e emissoes na Uniao Europeia. A Geracao Distribuida (GD) de energia, nomeadamente atraves de sistemas de cogeracao e tecnologias solares, representa um papel importante no futuro energetico deste setor. A otimizacao do funcionamento dos sistemas de cogeracao e uma tarefa complexa, devido as diversas variaveis em jogo, designadamente: os diferentes tipos de necessidades energeticas (eletricidade, aquecimento e arrefecimento), os precos dinamicos dos combustiveis (gas natural) e da eletricidade, e os custos fixos e variaveis dos diferentes sistemas de GD. Tal torna-se mais complexo considerando a natureza flutuante das tecnologias solares termicas e fotovoltaicas. Ao mesmo tempo, a liberalizacao do mercado da eletricidade permite exportar para a rede, a electricidade gerada localmente. Adicionalmente, a operacao estrategica de um sistema de GD deve atender aos quadros politicos nacionais, se tiver como objetivo beneficiar de tais regimes. Alem disso, considerando os elevados impactes ambientais do setor da construcao, qualquer avaliacao energetica de edificios rigorosa deve tambem integrar aspetos ambientais, utilizando uma abordagem de Ciclo de Vida (CV). Uma avaliacao de Ciclo de Vida (ACV) completa de um sistema de GD deve incluir as fases relativas a operacao e construcao do sistema, bem como os impactes associados a producao dos combustiveis. Foram analisadas as emissoes da producao de GN, as quais variam de acordo com a origem, tipo (convencional ou nao-convencional), e estado (na forma de GN Liquefeito (GNL) ou gas). Do mesmo modo, o impacte dos sistemas solares e afetado pela meteorologia e radiacao solar, de acordo com a sua localizacao geografica. Sendo assim, uma avaliacao adequada dos sistemas de GD exige um modelo de ACV adequado a localizacao geografica (Portugal), integrando tambem a producao de combustivel (GN), tendo em conta as suas diferentes fontes de abastecimento. O principal objetivo desta tese de doutoramento foi desenvolver um modelo para otimizar o desenho e operacao de sistemas de GD para o setor da construcao de edificios comerciais em Portugal, considerando os respetivos Impactes de Ciclo de Vida (IAVC) e Custos de Ciclo de Vida (CCV), de modo a satisfazer as necessidades energeticas do edificio. Tres tipos de tecnologias de cogeracao (Micro-Turbinas, Motores de combustao interna, e Celulas combustiveis de Oxido solido), e dois tipos de tecnologias de energia solar, solar termica e fotovoltaica, constituem os sistemas de GD que sao acoplados aos sistemas convencionais. Foi desenvolvido um modelo de CV, tendo em conta todos os impactes relacionados com a construcao e operacao dos sistemas de energia, bem como os processos a montante relacionados com a producao do GN. Em particular, o mix de GN consumido em Portugal em 2011 foi identificado (60% da Nigeria, 40% da Argelia) e os impactes relativos a cada uma das vias de abastecimento foram avaliados separadamente para quatro categorias de impacte ambiental: Consumo de Energia Primaria (CEP), Gases com Efeito de Estufa (GEE), acidificacao, e eutrofizacao. Devido a importancia das emissoes de GEE na formulacao de politicas, foi tambem realizada uma analise de incerteza as emissoes de GEE do GN fornecido a Portugal. Foi desenvolvido um modelo matematico, em linguagem de Programacao General Algebraic Modeling System (GAMS), que utiliza os resultados da ACV dos sistemas de energia e as suas implicacoes economicas para minimizar o CCV e IACV ao longo de um horizonte de planeamento definido pelo decisor. Foram derivadas fronteiras otimas de Pareto, representando as relacoes entre o tipo de IACV (CEP, GEE, acidificacao, eutrofizacao) e CCV decorrentes da satisfacao das necessidades energeticas do edificio. Para aumentar a robustez do modelo, dada a incerteza dos precos dos combustiveis (GN e eletricidade), foi desenvolvido um modelo de custos robusto para os sistemas de GD, que e menos afetado por perturbacoes relativas aos custos de combustivel. A aplicacao do modelo proposto foi testada num caso de estudo real, um edificio comercial localizado na cidade de Coimbra, em Portugal.

Physical Properties of Blood Are Altered in Young and Lean Women with Polycystic Ovary Syndrome.

PubMed

Simmonds, Michael J; Milne, Nikki; Ong, Kee; Brotherton, Emily; McNamee, Antony P; Horobin, Jarod; Sabapathy, Surendran

2016-01-01

Classic features of polycystic ovary syndrome (PCOS) include derangement of metabolic and cardiovascular health, and vascular dysfunction is commonly reported. These comorbidities indicate impaired blood flow; however, other than limited reports of increased plasma viscosity, surprisingly little is known regarding the physical properties of blood in PCOS. We aimed to investigate whether haemorheology was impaired in women with PCOS. We thus measured a comprehensive haemorheological profile, in a case-control design, of lean women with PCOS and age-matched healthy controls. A clinical examination determined similar cardiovascular risk for the two groups. Whole blood and plasma viscosity was measured using a cone-plate viscometer. The magnitude and rate of red blood cell (RBC) aggregation was determined using a light-transmission aggregometer, and the degree of RBC deformability was measured via laser-diffraction ektacytometry. Plasma viscosity was significantly increased in women with PCOS. Blood viscosity was also increased for PCOS at lower-to-moderate shear rates in both native and standardised haematocrit samples. The magnitude of RBC aggregation-a primary determinant of low-shear blood viscosity-was significantly increased in PCOS at native and 0.4 L·L-1 haematocrit. No difference was detected between PCOS and CON groups for RBC deformability measurements. A novel measure indicating the effectiveness of oxygen transport by RBC (i.e., the haematocrit-to-viscosity ratio; HVR) was decreased at all shear rates in women with PCOS. In a group of young and lean women with PCOS with an unremarkable cardiovascular risk profile based on clinical data, significant haemorheological impairment was observed. The degree of haemorheological derangement observed in the present study reflects that of overt chronic disease, and provides an avenue for future therapeutic intervention in PCOS.

Factors associated with poor sleep quality in women with cancer.

PubMed

Mansano-Schlosser, Thalyta Cristina; Ceolim, Maria Filomena

2017-03-02

to analyze the factors associated with poor sleep quality, its characteristics and components in women with breast cancer prior to surgery for removing the tumor and throughout the follow-up. longitudinal study in a teaching hospital, with a sample of 102 women. The following were used: a questionnaire for sociodemographic and clinical characterization, the Pittsburgh Sleep Quality Index; the Beck Depression Inventory; and the Herth Hope Scale. Data collection covered from prior to the surgery for removal of the tumor (T0) to T1, on average 3.2 months; T2, on average 6.1 months; and T3, on average 12.4 months. Descriptive statistics and the Generalized Estimating Equations model were used. depression and pain contributed to the increase in the score of the Pittsburgh Sleep Quality Index, and hope, to the reduction of the score - independently - throughout follow-up. Sleep disturbances were the component with the highest score throughout follow-up. the presence of depression and pain, prior to the surgery, contributed to the increase in the global score of the Pittsburgh Sleep Quality Index, which indicates worse quality of sleep throughout follow-up; greater hope, in its turn, influenced the reduction of the score of the Pittsburgh Sleep Quality Index. analizar los factores asociados a la mala calidad del sueño, sus características y componentes en mujeres con cáncer de mama, antes de la cirugía de retirada del tumor y a lo largo del seguimiento. estudio longitudinal, en hospital universitario con muestra de 102 mujeres. Fueron utilizados: un cuestionario de caracterización sociodemográfica y clínica; el Índice de Calidad del Sueño de Pittsburgh; el Inventario de Depresión de Beck; y la Escala de Esperanza de Herth. La recolección comprendió los momentos: antes de la cirugía de retirada del tumor (T0), en (T1) en promedio 3,2 meses, en (T2) en promedio 6,1 meses y en (T3) en promedio 12,4 meses. Se utilizó estadística descriptiva y el modelo de Ecuaciones de Estimación Generalizada. la depresión y el dolor contribuyeron para el aumento del puntaje del Índice de Calidad del Sueño de Pittsburgh y la esperanza para la reducción del puntaje, de manera independiente, a lo largo del seguimiento. Los trastornos del sueño fueron el componente con puntuación más elevada, a lo largo del seguimiento. la presencia de la depresión y del dolor, previos a la cirugía, contribuyeron para el aumento del puntaje global del Índice de Calidad del Sueño de Pittsburgh, lo que indica peor calidad del sueño, a lo largo del seguimiento y, la mayor esperanza, a su vez, influenció en la reducción del puntaje del Índice de Calidad del Sueño de Pittsburgh. analisar os fatores associados à má qualidade do sono, suas características e componentes em mulheres com câncer de mama antes da cirurgia de retirada do tumor e ao longo do seguimento. estudo longitudinal, em hospital universitário com amostra de 102 mulheres. Foram utilizados: questionário de caracterização sociodemográfica e clínica, Índice de Qualidade do Sono de Pittsburgh; Inventário de Depressão de Beck; Escala de Esperança de Herth. Coleta compreendeu antes da cirurgia de retirada do tumor (T0) em T1, em média 3,2 meses; T2, em média 6,1 meses; T3, em média 12,4 meses. Utilizou-se estatística descritiva e o modelo de Equações de Estimação Generalizada. a depressão e a dor contribuíram para o aumento do escore do Índice de Qualidade de Sono de Pittsburgh, e a esperança, para a redução do escore, de maneira independente, ao longo do seguimento. Os transtornos do sono foram o componente com pontuação mais elevada, ao longo do seguimento. a presença de depressão e de dor, previamente à cirurgia, contribuiu para o aumento do escore global do Índice de Qualidade do Sono de Pittsburgh, o que indica pior qualidade do sono, ao longo do seguimento e, a maior esperança, por sua vez, influenciou na redução do escore do Índice de Qualidade do Sono de Pittsburgh.

Re-Creating Missing Population Baselines for Pacific Reef Sharks

PubMed Central

Nadon, Marc O; Baum, Julia K; Williams, Ivor D; Mcpherson, Jana M; Zgliczynski, Brian J; Richards, Benjamin L; Schroeder, Robert E; Brainard, Russell E

2012-01-01

Summary Abstract Sharks and other large predators are scarce on most coral reefs, but studies of their historical ecology provide qualitative evidence that predators were once numerous in these ecosystems. Quantifying density of sharks in the absence of humans (baseline) is, however, hindered by a paucity of pertinent time-series data. Recently researchers have used underwater visual surveys, primarily of limited spatial extent or nonstandard design, to infer negative associations between reef shark abundance and human populations. We analyzed data from 1607 towed-diver surveys (>1 ha transects surveyed by observers towed behind a boat) conducted at 46 reefs in the central-western Pacific Ocean, reefs that included some of the world's most pristine coral reefs. Estimates of shark density from towed-diver surveys were substantially lower (<10%) than published estimates from surveys along small transects (<0.02 ha), which is not consistent with inverted biomass pyramids (predator biomass greater than prey biomass) reported by other researchers for pristine reefs. We examined the relation between the density of reef sharks observed in towed-diver surveys and human population in models that accounted for the influence of oceanic primary productivity, sea surface temperature, reef area, and reef physical complexity. We used these models to estimate the density of sharks in the absence of humans. Densities of gray reef sharks (Carcharhinus amblyrhynchos), whitetip reef sharks (Triaenodon obesus), and the group “all reef sharks” increased substantially as human population decreased and as primary productivity and minimum sea surface temperature (or reef area, which was highly correlated with temperature) increased. Simulated baseline densities of reef sharks under the absence of humans were 1.1–2.4/ha for the main Hawaiian Islands, 1.2–2.4/ha for inhabited islands of American Samoa, and 0.9–2.1/ha for inhabited islands in the Mariana Archipelago, which suggests that density of reef sharks has declined to 3–10% of baseline levels in these areas. Resumen Los tiburones y otros depredadores mayores son escasos en la mayoría de los arrecifes de coral, pero estudios de su ecología histórica proporcionan evidencia cualitativa de que los depredadores una vez fueron numerosos en estos ecosistemas. Sin embargo, la cuantificación de la densidad de tiburones en ausencia de humanos (línea de base) es obstaculizada por la falta de datos de series de tiempo pertinentes. Recientemente, los investigadores han utilizado muestreos visuales submarinos, de extensión espacial limitada o de diseño no estándar, para inferir asociaciones negativas entre la abundancia de tiburones de arrecife y las poblaciones humanas. Analizamos datos de 1607 muestreos por remolque de buzos (transectos >1ha muestreados por observadores remolcados por una lancha) realizados en 46 arrecifes en el Océano Pacífico centro-occidental, arrecifes que incluyeron algunos de los más prístinos del mundo. Las estimaciones de densidad de tiburones fue sustancialmente menor (<10%) que estimaciones publicadas a partir de muestreos a lo largo de transectos pequeños (<0.02 ha), lo cual no es consistente con las pirámides de biomasa invertidas (la biomasa de depredadores es mayor que la biomasa de presas) reportadas para arrecifes prístinos por otros autores. Examinamos la relación entre la densidad de tiburones de arrecife observados en los muestreos por remolque de buzos y la población humana en modelos y consideramos la influencia de la productividad oceánica primaria, la temperatura de la superficie del mar, la superficie del arrecife y su complejidad física. Utilizamos estos modelos para estimar la densidad de tiburones en ausencia de humanos. Las densidades de Carcharhinus amblyrhynchos, Triaenodon obesus y el grupo de “tiburones estrictamente arrecifales” incrementó sustancialmente a medida que disminuyó la población humana y que incrementó la productividad primaria y la temperatura de la superficie del mar (o superficie del arrecife, que estaba altamente correlacionada con la temperatura. Las densidades basales simuladas de tiburones arrecifales en ausencia de humanos fueron 1.1–2.4/ha para las Islas Hawaianas, 1.2–2.4/ha en islas deshabitadas de Samoa Americana y 0.9–2.1/ha e islas deshabitadas del Archipiélago Mariana, lo que sugiere que la densidad de tiburones arrecifales ha declinado entre 3 -10% en relación con los niveles basales en esas áreas. PMID:22536842

A geochemical and geophysical approach to derive a conceptual circulation model of CO2-rich mineral waters: A case study of Vilarelho da Raia, northern Portugal

NASA Astrophysics Data System (ADS)

Marques, J. M.; Santos, Monteiro; Graça, R. C.; Castro, R.; Aires-Barros, L.; Mendes Victor, L. A.

2001-11-01

The Vilarelho da Raia-Chaves region, located in northern Portugal adjacent to the Spanish border, is characterized by both hot and cold CO2-rich mineral waters issuing from springs and drilled wells. The present paper updates the conceptual circulation model of the Vilarelho da Raia cold CO2-rich mineral waters. Vilarelho da Raia mineral waters, dominated by Na and HCO3 ions, have formed mainly by interaction with CO2 of deep-seated mantle origin. The δ18O, δ2H and 3H values indicate that these waters are the result of meteoric waters infiltrating into Larouco Mountain, NW of Vilarelho da Raia, circulating at shallow depths in granitic rocks and moving into Vilarelho da Raia area. The conceptual geochemical and geophysical circulation model indicates that the hot and cold CO2-rich mineral waters of Chaves (76 °C) and Vilarelho da Raia (17 °C) should be considered manifestations of similar but not the same geohydrological systems. Résumé. La région de Vilarelho da Raia - Chaves, située au Portugal près de la frontière Espagnole, est caractérisée par des eaux carbogazeuses, chaudes et froides, émergeant à des sources et dans des puits. Ce travail constitue une mise au point du modèle conceptuel de circulation des eaux minérales carbogazeuses froides de Vilarelho da Raia. Les eaux minérales de Vilarelho da Raia, dans lesquelles les ions Na and HCO3 sont dominants, résultent principalement d'interactions avec du CO2 d'origine mantellique. Les δ18O, les δ2H, et les teneurs en 3H indiquent que ces eaux proviennent de l'infiltration d'eaux météoriques dans le Mont Larouco au NW de Vilarelho da Raia, circulant à faible profondeur dans les granites en direction de la région de Vilarelho da Raia. Le modèle de circulation géochimique et géophysique conduit à penser que les eaux minérales carbogazeuses chaudes et froides de Chaves (76 °C) et de Vilarelho da Raia (17 °C) doivent être considérées comme des manifestations de systèmes hydrogéologiques similaires, mais non identiques. Resumen. La región de Vilarelho-Chaves está situada en el Norte de Portugal, junto a la frontera con España. Se caracteriza por la existencia de aguas minerales calientes y frías enriquecidas en CO2, que descargan mediante manantiales y pozos. El artículo tiene como objetivo la actualización del modelo conceptual de flujo de las aguas frías de Vilarelho de Raia, que son ricas en CO2. Dichas aguas se han formado fundamentalmente por la interacción con el CO2 procedente del manto profundo, y son del tipo bicarbonatado sódico. Los valores de δ18O, δ2H y 3H indican que proceden de la infiltración de agua meteórica en la Montaña Larouco -al Noroeste de Vilarelho de Raia-, que circulan a poca profundidad en un medio formado por de rocas graníticas y se mueven hacia el área de Vilarelho de Raia. El modelo conceptual de flujo, basado en datos geoquímicos y geofísicos, indica que las aguas minerales calientes de Chaves (76 °C) y las frías de Vilarelho de Raia (17 °C), ambas enriquecidas en CO2, no deben ser consideradas como manifestaciones de un único sistema hidrogeológico, sino de dos similares.

Perda de massa em ventos empoeirados de estrelas supergigantes

NASA Astrophysics Data System (ADS)

Vidotto, A. A.; Jatenco-Pereira, V.

2003-08-01

Em praticamente todas as regiões do diagrama HR, as estrelas apresentam evidências observacionais de perda de massa. Na literatura, pode-se encontrar trabalhos que tratam tanto do diagnóstico da perda de massa como da construção de modelos que visam explicá-la. O amortecimento de ondas Alfvén tem sido utilizado como mecanismo de aceleração de ventos homogêneos. Entretanto, sabe-se que os envelopes de estrelas frias contêm grãos sólidos e moléculas. Com o intuito de estudar a interação entre as ondas Alfvén e a poeira e a sua conseqüência na aceleração do vento estelar, Falceta-Gonçalves & Jatenco-Pereira (2002) desenvolveram um modelo de perda de massa para estrelas supergigantes. Neste trabalho, apresentamos um estudo do modelo acima proposto para avaliar a dependência da taxa de perda de massa com alguns parâmetros iniciais como, por exemplo, a densidade r0, o campo magnético B0, o comprimento de amortecimento da onda L0, seu fluxo f0, entre outros. Sendo assim, aumentando f0 de 10% a partir de valores de referência, vimos que aumenta consideravelmente, enquanto que um aumento de mesmo valor em r0, B0 e L0 acarreta uma diminuição em .

An experimental analysis of the real contact area between an electrical contact and a glass plane

NASA Astrophysics Data System (ADS)

Down, Michael; Jiang, Liudi; McBride, John W.

2013-06-01

The exact contact between two rough surfaces is usually estimated using statistical mathematics and surface analysis before and after contact has occurred. To date the majority of real contact and loaded surfaces has been theoretical or by numerical analyses. A method of analysing real contact area under various loads, by utilizing a con-contact laser surface profiler, allows direct measurement of contact area and deformation in terms of contact force and plane displacement between two surfaces. A laser performs a scan through a transparent flat side supported in a fixed position above the base. A test contact, mounted atop a spring and force sensor, and a screw support which moves into contact with the transparent surface. This paper presents the analysis of real contact area of various surfaces under various loads. The surfaces analysed are a pair of Au coated hemispherical contacts, one is a used Au to Au coated multi-walled carbon nanotubes surface, from a MEMS relay application, the other a new contact surface of the same configuration.

Effects of dietary fat and crude protein on feedlot performance, carcass characteristics, and meat quality in finishing steers fed differing levels of dried distillers grains with solubles.

PubMed

Gunn, P J; Weaver, A D; Lemenager, R P; Gerrard, D E; Claeys, M C; Lake, S L

2009-09-01

The objective of this study was to evaluate the influence of dietary protein and fat from distillers dried grains with solubles (DDGS) on feedlot performance, carcass characteristics, and meat quality in finishing steers. Angus-cross steers (n = 105; 443 +/- 20 kg of BW) were blocked by BW and randomly assigned to 1 of 5 dietary treatments: 1) corn-based diet with DDGS included at 25% of DM (CON), 2) CON with DDGS included at twice the amount of CON (50% of DM; 50DDGS), 3) CON with added corn protein to equal the CP in the 50DDGS diet (CON+CP), 4) CON with added vegetable oil to equal the fat in the 50DDGS diet (CON+VO), and 5) CON with protein and fat added to equal the CP and fat in the 50DDGS diet (CON+CPVO). Steers were fed to a common 12th-rib fat depth endpoint (1.3 +/- 0.2 cm; 68 to 125 d on trial). Loins and rounds were collected from 44 carcasses for Warner-Bratzler shear force (WBSF), ether extract, and case-life analyses. Data were analyzed using the MIXED procedure of SAS. Contrasts between 1) CON vs. elevated CP diets (50DDGS, CON+CP, and CON+CPVO; EP), 2) CON vs. elevated fat diets (50DDGS, CON+VO, and CON+CPVO; EF) and 3) CON vs. diets with elevated CP and fat (50DDGS and CON+CPVO; EPF) were analyzed. There were no differences in days on feed or DMI among treatments. Steers fed CON had greater ADG (P or= 0.06). Steers fed the CON diet had greater marbling scores (P or= 0.44). However, CON steers had greater (P = 0.02) L* values than EF-fed steers and greater b* values than EP, EF, and EPF steers (P

A causa das estações do ano: modelos mentais

NASA Astrophysics Data System (ADS)

de Campos, J. A. S.; de Araujo, J. F. S.

2003-08-01

A década de 70 do século passado foi marcada pelo estudo das concepções alternativas que os alunos trazem para a sala de aula. A identificação destas concepções foi o ponto de partida para promover a mudança conceitual, onde as pré-concepções seriam trocadas pelas concepções científicas. Na década seguinte, surgiram muitas propostas de estratégias educacionais para facilitar esta troca, na sua maioria baseadas na idéia do conflito cognitivo, proposta por Piaget. Entretanto, os resultados pouco animadores conduziram à percepção de que a mudança conceitual é um processo mais complexo. Pelas idéias da Ciência Cognitiva, a mudança conceitual é uma mudança progressiva dos modelos mentais que o aluno tem sobre o mundo físico, através de enriquecimento e revisão. A causa das Estações do Ano é um tópico sobre o qual a maioria dos estudantes apresenta concepções alternativas. Os autores fizeram um levantamento sobre as pré-concepções encontradas em trabalhos sobre o tema (16 referências), procurando encontrar elementos comuns que indicassem a presença de modelos mentais específicos. As pré-concepções encontradas na literatura foram obtidas usando-se diversas metodologias (desde entrevistas clínicas até questionários de múltipla escolha) e envolvendo alunos e professores de diferentes regiões geográficas. A partir de uma análise aprofundada de cada trabalho, e utilizando-se a técnica das Redes Sistêmicas, chegou-se a conclusão que as diversas pré-concepções identificadas (em torno de 50), poderiam ser representadas por 6 modelos mentais, onde a explicação da causa das estações do ano tem um mecanismo causal responsável. Os mecanismos causais identificados foram: a dependência da distância, a dependência da orientação, a dependência conjunta da distância e orientação, a dependência da obstrução, a dependência da velocidade e a dependência da inclinação dos raios solares. Foram ainda identificadas associações alternativas, que são um conjunto de pré-concepções, onde não existe a idéia de um modelo científico completo mas, sim, fragmentos de observação do dia a dia das pessoas.

78 FR 58559 - United States

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-24

... license to ten Modelo Brand Beers, including Corona Extra, this country's bestselling imported beer and... failure of the government to discharge its duty, the Court, in making its public interest finding, should...

Understanding differences in access and use of healthcare between international immigrants to Chile and the Chilean-born: a repeated cross-sectional population-based study in Chile

PubMed Central

2012-01-01

Introduction International evidence indicates consistently lower rates of access and use of healthcare by international immigrants. Factors associated with this phenomenon vary significantly depending on the context. Some research into the health of immigrants has been conducted in Latin America, mostly from a qualitative perspective. This population-based study is the first quantitative study to explore healthcare provision entitlement and use of healthcare services by immigrants in Chile and compare them to the Chilean-born. Methods Data come from the nationally representative CASEN (Socioeconomic characterization of the population in Chile) surveys, conducted in 2006 and 2009. Self-reported immigrants were compared to the Chilean-born, by demographic characteristics (age, sex, urban/rural, household composition, ethnicity), socioeconomic status (SES: education, household income, contractual status), healthcare provision entitlement (public, private, other, none), and use of primary services. Weighted descriptive, stratified and adjusted regression models were used to analyse factors associated with access to and use of healthcare. Results There was an increase in self-reported immigrant status and in household income inequality among immigrants between 2006 and 2009. Over time there was a decrease in the rate of immigrants reporting no healthcare provision and an increase in reporting of private healthcare provision entitlement. Compared to the Chilean-born, immigrants reported higher rates of use of antenatal and gynaecological care, lower use of well-baby care, and no difference in the use of Pap smears or the number of attentions received in the last three months. Immigrants in the bottom income quintile were four times more likely to report no healthcare provision than their equivalent Chilean-born group (with different health needs, i.e. vertical inequity). Disabled immigrants were more likely to have no healthcare provision compared to the disabled Chilean-born (with similar health needs, i.e. horizontal inequity). Factors associated with immigrants’ access to, and use of, healthcare were sex, urban/rural status, education and country of origin. Conclusion There were significant associations between SES, and access to and use of healthcare among immigrants in Chile and a higher prevalence of no health care provision entitlement among poor and disabled immigrants compared to the Chilean-born. Changing associations between access and use of healthcare and SES among immigrants in Chile over time may reflect changes in their socio-demographic composition or in the survey methodology between 2006 and 2009. Resumen Introducción La evidencia internacional indica menor acceso y uso de servicios de salud por parte de inmigrantes, pero sus factores desencadenantes varían significativamente dependiendo del contexto. Algunas investigaciones se han desarrollado en este tema en América Latina, desde una perspectiva cualitativa. Este estudio cuantitativo exploró el auto-reporte de acceso y uso de servicios de salud de inmigrantes en Chile y los comparó con la población chilena. Métodos Análisis secundario de datos de encuesta nacional CASEN 2006 y 2009. Inmigrantes fueron comparados con chilenos en características demográficas (edad, sexo, urbano/rural, composición del hogar, etnia), estatus socioeconómico (educación, ingreso, situación contractual), tipo de previsión (pública, privada, otra, ninguna), y uso de varios servicios de atención primaria. Análisis descriptivo, estratificado, y modelos de regresión ponderados para entender factores asociados al acceso y uso de servicios de salud en STATA 11.0. Resultados Se observó un aumento de reporte de inmigrantes y de la desigualdad en el ingreso de inmigrantes entre 2006 y 2009. Hubo una disminución en la tasa de inmigrantes sin previsión y un aumento en el acceso al sistema privado. Los inmigrantes usaron más frecuentemente la atención prenatal y ginecológica, y menos la atención del niño sano. No hubo diferencia en el uso de citología vaginal o el número total de atenciones recibidas en comparación con los chilenos. Los inmigrantes en el quintil inferior de ingresos reportaron 4 veces más la ausencia de prestación de salud que los chilenos (inequidad vertical). Similares resultados se observaron al comparar inmigrantes con discapacidad con chilenos con discapacidad (inequidad horizontal). Los factores asociados con el acceso y uso del servicio de salud por parte de los inmigrantes fueron el sexo, urbano/rural, educación y país de origen. Conclusión Se observó una asociación significativa entre estatus socioeconomico, migración y acceso y uso de asistencia sanitaria. Los resultados de este estudio pueden deberse a verdaderos cambios en la composición de los inmigrantes y sus patrones de uso del sistema de salud chileno, pero también pueden deberse a cambios en la metodología y recolección de datos entre encuestas 2006 y 2009. Este aspecto requiere mayor análisis y debate en la región. PMID:23158113

A thick lens of fresh groundwater in the southern Lihue Basin, Kauai, Hawaii, USA

NASA Astrophysics Data System (ADS)

Izuka, Scot; Gingerich, Stephen

2002-11-01

A thick lens of fresh groundwater exists in a large region of low permeability in the southern Lihue Basin, Kauai, Hawaii, USA. The conventional conceptual model for groundwater occurrence in Hawaii and other shield-volcano islands does not account for such a thick freshwater lens. In the conventional conceptual model, the lava-flow accumulations of which most shield volcanoes are built form large regions of relatively high permeability and thin freshwater lenses. In the southern Lihue Basin, basin-filling lavas and sediments form a large region of low regional hydraulic conductivity, which, in the moist climate of the basin, is saturated nearly to the land surface and water tables are hundreds of meters above sea level within a few kilometers from the coast. Such high water levels in shield-volcano islands were previously thought to exist only under perched or dike-impounded conditions, but in the southern Lihue Basin, high water levels exist in an apparently dike-free, fully saturated aquifer. A new conceptual model of groundwater occurrence in shield-volcano islands is needed to explain conditions in the southern Lihue Basin. Résumé. Dans le sud du bassin de Lihue (Kauai, Hawaii, USA), il existe une épaisse lentille d'eau souterraine douce dans une vaste région à faible perméabilité. Le modèle conceptuel conventionnel pour la présence d'eau souterraine à Hawaii et dans les autres îles de volcans en bouclier ne rend pas compte d'une lentille d'eau douce si épaisse. Dans ce modèle conceptuel, les accumulations de lave dont sont formés la plupart des volcans en bouclier couvrent de vastes régions à relativement forte perméabilité, avec des lentilles d'eau douce peu épaisses. Dans le sud du bassin de Lihue, les laves remplissant le bassin et les sédiments constituent une région étendue à faible conductivité hydraulique régionale, qui, sous le climat humide du bassin, est saturée presque jusqu'à sa surface; les surfaces piézométriques sont plusieurs centaines de mètres au-dessus du niveau de la mer à quelques kilomètres de la côte. On pensait jusqu'à présent que des niveaux piézométriques aussi élevés dans des îles de volcans en bouclier n'existaient que dans le cas de nappes perchées ou de blocage par un dyke, mais dans le sud du bassin de Lihue, des niveaux piézométriques élevés existent dans un aquifère apparemment sans dyke et complètement saturé. Un nouveau modèle conceptuel de présence d'eau souterraine dans les îles de volcans en bouclier est nécessaire pour expliquer les conditions observées dans le sud du bassin de Lihue. Resumen. Se ha determinado la existencia de un espeso lentejón de aguas subterráneas dulces en una extensa región de baja permeabilidad situada al sur de la cuenca de Lihue, en Kauai (Hawaii, Estados Unidos de América). El modelo conceptual convencional de las aguas subterráneas en Hawai y en otros cinturones de islas volcánicas no considera la existencia de lentejones tan gruesos de agua dulce. En dicho modelo, las acumulaciones de flujos de lava que constituyen la mayoría de los cinturones volcánicos se desarrollan en grandes áreas de permeabilidad relativamente baja y con pequeños lentejones de agua dulce. En el sur de la cuenca de Lihue, las lavas de relleno y los sedimentos forman una región extensa de baja conductividad hidráulica regional que, con el clima húmedo de la zona, está saturada hasta prácticamente la superficie del terreno, mientras que el nivel freático se encuentra centenares de metros por encima del nivel del mar a pocos kilómetros de la línea de costa. Se creía hasta ahora que, en los cinturones de islas volcánicas, tales niveles sólo tenían lugar en acuíferos colgados o en condiciones de confinamiento por diques, pero, al sur de la cuenca de Lihue, se dan en acuíferos completamente saturados que no están limitados por diques. Se necesita un nuevo modelo conceptual de las aguas subterráneas en cinturones de islas volcánicas para explicar las condiciones halladas en la cuenca meridional de Lihue.

Covalent organic nanosheets for effective charge transport layers in planar-type perovskite solar cells.

PubMed

Park, Soyun; Kim, Min-Sung; Jang, Woongsik; Park, Jin Kuen; Wang, Dong Hwan

2018-03-08

Herein, solvent-treated bandgap-tunable covalent organic nanosheets (CONs) were prepared via the Stille cross-coupling reaction. These materials are considered useful as interlayers in photovoltaic devices upon the alignment of energy levels between other components. Among various types of solar cells, according to the organic-interlayer study, inverted planar perovskite solar cells (PSCs) are mostly demanded to effectively transport and collect charge carriers due to their high performance. At first, the C-V analysis proved the energy levels of the frontier orbitals for CON-10 and CON-16 nanosheets; this verified the suitability of these nanosheets as hole transport layers (HTLs) with the PEDOT:PSS upon casting both films from DMSO. It became evident, however, that the hole transport property of the PEDOT:PSS on the CON-16 layer was unfavorable with the increasing UPS-proven hole injection barrier. In addition, both CONs induced a rough surface morphology; however, CON-10 showed a relatively smooth surface as compared to CON-16 based on the Scanning electron microscopy (SEM) and Atomic force microscopy (AFM) profiles; furthermore, their surface properties influenced both the PEDOT:PSS layers and the perovskite layers. Especially, the XRD profiles presented an enhanced crystallinity of the perovskite layers with CON-10. All these aspects indicate that CON-10 is a more effective HTL material, and several versions of perovskite solar cells (PSCs) have been fabricated with/without CON-10 and CON-16 together with the PEDOT:PSS to determine the more-HTL-suitable CON. As a result, the power conversion efficiencies (PCEs) of the optimized devices with CON-10 exhibited a value of 10.2%, which represented a 1% increase over those of the reference devices without the CONs and was 4% higher than that of the CON-16 devices. Moreover, the devices with CON-10 were further optimized with TiO x using Al electrodes, leading to a PCE increase of these devices that became slightly higher than the PCEs of the device with CON-10 and without TiO x . This tendency was supported by photoluminescence (PL) spectroscopy, photocurrent density (J ph ), and space-charge-limited current (SCLC) mobility results.

Sobre a largura da última superfície de espalhamento

NASA Astrophysics Data System (ADS)

Nobre, M. A. S.; Pires, N.; Lima, J. A. S.

2003-08-01

De acordo com o modelo do "Big-Bang", no universo primordial a matéria estava em equilíbrio térmico com a radiação. Com a expansão a temperatura da radiação cai. Quando a temperatura chega em torno dos 4.000K, os espalhamentos diminuem, começando a recombinação dos prótons e elétrons em Hidrogênio neutro (era conhecida como da recombinação). Ao final da recombinação, os fótons se propagam livremente sofrendo, em princípio, somente os efeitos do "redshift" cosmológico. Esses fótons nos alcançam hoje como a radiação cósmica de fundo (RCF), e parecem vir de uma superfície esférica ao nosso redor, tal que o raio dela é a distância que ele viajou desde seu último espalhamento na época da recombinação. Naturalmente, esse processo não ocorreu abruptamente, implicando na existência de uma largura no espaço dos "redshifts" que deve depender do modelo cosmológico específico e dos processos físicos considerados. Neste trabalho analisamos os efeitos de diferentes modelos - a saber, aqueles com decaimento do vácuo L(t), criação de matéria, quintessência e gás de Chaplygin - sobre a última superfície de espalhamento da RCF, em particular sua largura e a função visibilidade, que determina a probabilidade de um fóton ter tido seu último espalhamento num "redshift" z. No caso particular dos modelos com decaimento do vácuo, existe uma forte dependência da função visibilidade com L(t). Tais efeitos poderão ser testados através da análise dos resultados de experimentos mais precisos que estão atualmente em andamento, como por exemplo, o WMAP.

Greater Proptosis Is Not Associated With Improved Compressive Optic Neuropathy in Thyroid Eye Disease.

PubMed

Nanda, Tavish; Dunbar, Kristen E; Campbell, Ashley A; Bathras, Ryan M; Kazim, Michael

2018-05-18

Despite the paucity of supporting data, it has generally been held that proptosis in thyroid eye disease (TED) may provide relative protection from compressive optic neuropathy (CON) by producing spontaneous decompression. The objective of this study was to investigate this phenomenon in patients with bilateral TED-CON. We retrospectively reviewed the charts of 67 patients (134 orbits) with bilateral TED-CON at Columbia-Presbyterian Medical Center. Significant asymmetric proptosis (Hertel) was defined as ≥ 2 mm. Significant asymmetric CON was defined first, as the presence of an relative afferent pupillary defect. Those without an relative afferent pupillary defect were evaluated according to the TED-CON formula y = -0.69 - 0.31 × (motility) - 0.2 × (mean deviation) - 0.02 × (color vision) as previously established for the diagnosis of TED-CON. A difference in the formula result ≥ 1.0 between eyes was considered significant. Patients were then divided into 4 groups. Forty-one of 67 patients demonstrated asymmetric CON (29 by relative afferent pupillary defect, 12 by formula). Twenty-one of 67 patients demonstrated asymmetric proptosis. Only 5 of 12 (41.6%) of the patients who had both asymmetric proptosis and asymmetric CON (group 1) showed greater proptosis in the eye with less CON. Twenty-nine patients (group 2) showed that asymmetric CON occurred despite symmetrical proptosis. Seventeen patients (group 3), showed the inverse, that asymmetric differences in proptosis occurred with symmetrical CON. Despite commonly held assumptions, our results suggest that greater proptosis is not associated with improved TED-CON. Combining groups 1 to 3-all of which demonstrated asymmetry of either proptosis, CON, or both-91.4% of patients did not show a relationship between greater proptosis and improved CON.

The Pros and Cons of Army Automation

DTIC Science & Technology

2007-11-13

The Pros and Cons of Army Automation 1 Running Head: THE PROS AND CONS OF ARMY AUTOMATION The Pros and Cons of Army Automation SGM...TITLE AND SUBTITLE The Pros and Cons of Army Automation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...Prescribed by ANSI Std Z39-18 The Pros and Cons of Army Automation 2 Outline I. Introduction (MSG (P) Dostie) II. Manual skills (MSG (P

The thermal and mechanical deformation study of up-stream pumping mechanical seal

NASA Astrophysics Data System (ADS)

Chen, H. L.; Xu, C.; Zuo, M. Z.; Wu, Q. B.

2015-01-01

Taking the viscosity-temperature relationship of the fluid film into consideration, a 3-D numerical model was established by ANSYS software which can simulate the heat transfer between the upstream pumping mechanical seal stationary and rotational rings and the fluid film between them as well as simulate the thermal deformation, structure deformation and the coupling deformation of them. According to the calculation result, thermal deformation causes the seal face expansion and the maximum thermal deformation appears at the inside of the seal ring. Pressure results in a mechanical deformation, the maximum deformation occurs at the top of the spiral groove and the overall trend is inward the mating face, opposite to the thermal deformation. The coupling deformation indicate that the thermal deformation can be partly counteracted by pressure deformation. Using this model, the relationship between deformation and shaft speed and the sealing liquid pressure was studied. It's found that the shaft speed will both enhance the thermal and structure deformation and the fluid pressure will enhance the structure deformation but has little to do with the thermal deformation. By changing the sealing material, it's found that material with low thermal expansion coefficient and low elastic modulus will suffer less thermal-pressure deformation.

Importance of eccentric actions in performance adaptations to resistance training

NASA Technical Reports Server (NTRS)

Dudley, Gary A.; Miller, Bruce J.; Buchanan, Paul; Tesch, Per A.

1991-01-01

The importance of eccentric (ecc) muscle actions in resistance training for the maintenance of muscle strength and mass in hypogravity was investigated in experiments in which human subjects, divided into three groups, were asked to perform four-five sets of 6 to 12 repetitions (rep) per set of three leg press and leg extension exercises, 2 days each weeks for 19 weeks. One group, labeled 'con', performed each rep with only concentric (con) actions, while group con/ecc with performed each rep with only ecc actions; the third group, con/con, performed twice as many sets with only con actions. Control subjects did not train. It was found that resistance training wih both con and ecc actions induced greater increases in muscle strength than did training with only con actions.

Fixing a Reference Frame to a Moving and Deforming Continent

NASA Astrophysics Data System (ADS)

Blewitt, G.; Kreemer, C.; Hammond, W. C.

2016-12-01

The U.S. National Spatial Reference System will be modernized in 2022. A foundational component will be a geocentric reference frame fixed to the North America tectonic plate. Here we address challenges of fixing a reference frame to a moving and deforming continent. Scientific applications motivate that we fix the frame with a scale consistent with the SI system, an origin that coincides with the Earth system's center of mass, and with axes attached to the rigidly rotating interior of the North America plate. Realizing the scale and origin is now achieved to < 0.5 mm/yr by combining space-geodetic techniques (SLR, VLBI, GPS, and DORIS) in the global system, ITRS. To realize the no-net rotation condition, the complexity of plate boundary deformation demands that we only select GPS stations far from plate boundaries. Another problem is that velocity uncertainties in models of glacial isostatic adjustment (GIA) are significant compared to uncertainties in observed velocities. GIA models generally agree that far-field horizontal velocities tend to be directed toward/away from Hudson Bay, depending on mantle viscosity, with uncertain sign and magnitude of velocity. Also in the far field, strain rates tend to be small beyond the peripheral bulge ( US-Canada border). Thus the Earth's crust in the US east of the Rockies may appear to be rigid, even if this region moves relative to plate motion. This can affect Euler vector estimation, with implications (pros and cons) on scientific interpretation. Our previous approach [ref. 1] in defining the NA12 frame was to select a core set of 30 stations east of the Rockies and south of the U.S.-Canada border that satisfy strict criteria on position time series quality. The resulting horizontal velocities have an RMS of 0.3 mm/yr, quantifying a combination of plate rigidity and accuracy. However, this does not rule out possible common-mode motion arising from GIA. For the development of new frame NA16, we consider approaches to this problem. We also apply new techniques including the MIDAS robust velocity estimator [ref. 2] and "GPS Imaging" of vertical motions and strain rates (Fig. 1), which together could assist in better defining "stable North America".[1] Blewitt et al. (2013). J. Geodyn. 72, 11-24, doi:10.1016/j.jog.2013.08.004[2] Blewitt et al. (2016). JGR 121, doi:10.1002/2015JB012552

Deformation twinning in metals and ordered intermetallics-Ti and Ti-aluminides

NASA Astrophysics Data System (ADS)

Yoo, M. H.; Fu, C. L.; Lee, J. K.

1991-06-01

The role of deformation twinning in the strength and ductility of metals and ordered intermetallic alloys is examined on the basis of crystallography, energetics and kinetics of deformation twinning. A systematic analysis is made by taking Ti, Ti3AI, TiAl, and A13Ti as four model systems. In comparison with profuse twinning in Ti, the intrinsic difficulty of twinning in Ti3A1 is rationalized in terms of the interchange shuffling mechanism. A fault (SISF) dragging mechanism based on the interaction torque explains the physical source for the low mobility of screw superdislocations in TiAl, which may lead to (111) [ 11bar{2}] twin nucleation. In TiAl and A13Ti alloys, the twin-slip (ordinary) conjugate relationship makes an important contribution to the strain compatibility for high-temperature plasticity. Potentially beneficial alloying additions to promote twinning are discussed. Les conséquences de la déformation par maclage sur la fracture et la ductilité des métaux et alliages intermétalliques ordonnés sont étudiées en fonction de la cristallographie, de l'énergie et de la cinétique des déformations par maclage. Une analyse systématique a été faite en considérant Ti, Ti3AI, TiAl et A13Ti comme quatre systèmes modèles. En comparaison avec le nombre important de maclages observés dans Ti, la difficulté intrinsèque des maclages dans Ti3AI est rationalisée en terme de mécanisme d'“interchange shuffling”. Un mécanisme de “dragging fault” basé sur l'interaction “torque” explique l'origine physique de la faible mobilité des superdislocations vissées dans TiAl qui peuvent conduire à la nucléation des macles (111) 112. Dans les alliages tels TiAl et A13Ti, la relation conjuguée entre la macle et le glissement (ordinaire) contribue de façon importante à la compatibilité des contraintes lors de la déformation plastique à haute température. Des effets bénéfiques potentiels liés à des éléments d'addition sur le processus de maclage sont également discutés.

Spatial patterns of carbon, biodiversity, deforestation threat, and REDD+ projects in Indonesia

PubMed Central

Murray, Josil P; Grenyer, Richard; Wunder, Sven; Raes, Niels; Jones, Julia PG

2015-01-01

There are concerns that Reduced Emissions from Deforestation and forest Degradation (REDD+) may fail to deliver potential biodiversity cobenefits if it is focused on high carbon areas. We explored the spatial overlaps between carbon stocks, biodiversity, projected deforestation threats, and the location of REDD+ projects in Indonesia, a tropical country at the forefront of REDD+ development. For biodiversity, we assembled data on the distribution of terrestrial vertebrates (ranges of amphibians, mammals, birds, reptiles) and plants (species distribution models for 8 families). We then investigated congruence between different measures of biodiversity richness and carbon stocks at the national and subnational scales. Finally, we mapped active REDD+ projects and investigated the carbon density and potential biodiversity richness and modeled deforestation pressures within these forests relative to protected areas and unprotected forests. There was little internal overlap among the different hotspots (richest 10% of cells) of species richness. There was also no consistent spatial congruence between carbon stocks and the biodiversity measures: a weak negative correlation at the national scale masked highly variable and nonlinear relationships island by island. Current REDD+ projects were preferentially located in areas with higher total species richness and threatened species richness but lower carbon densities than protected areas and unprotected forests. Although a quarter of the total area of these REDD+ projects is under relatively high deforestation pressure, the majority of the REDD+ area is not. In Indonesia at least, first-generation REDD+ projects are located where they are likely to deliver biodiversity benefits. However, if REDD+ is to deliver additional gains for climate and biodiversity, projects will need to focus on forests with the highest threat to deforestation, which will have cost implications for future REDD+ implementation. Los Patrones Espaciales del Carbono, la Biodiversidad, la Amenaza de Deforestación y los Proyectos REDD+ en Indonesia Resumen Actualmente hay preocupación por que las Emisiones Reducidas de la Deforestación y Degradación del Bosque (REDD+, en inglés) puedan fallar en la entrega de co–beneficios potenciales de la biodiversidad si se enfocan en áreas de alto carbono. Exploramos los traslapes espaciales entre los stocks de carbono, la biodiversidad, las amenazas proyectadas de deforestación y la ubicación de proyectos REDD+ en Indonesia, un país tropical a la vanguardia del desarrollo REDD+. Para la biodiversidad, reunimos datos sobre la distribución de vertebrados terrestres (hábitats de anfibios, mamíferos, aves y reptiles) y plantas (modelos de distribución de especies para ocho familia). Después investigamos la congruencia entre las diferentes medidas de la riqueza de la biodiversidad y los stocks de carbono en la escala nacional y sub–nacional. Finalmente mapeamos proyectos REDD+ activos e investigamos la densidad de carbono y la riqueza potencial de la biodiversidad y modelamos presiones de deforestación dentro de estos bosques en relación con áreas protegidas y no protegidas. Hubo poco traslape interno entre los diferentes hotspots (el 10% más rico de las celdas) de riqueza de especies. Tampoco hubo congruencia espacial consecuente entre los stocks de carbono y las medidas de la biodiversidad: una correlación negativa débil en la escala nacional enmascaró las relaciones altamente variables y no-lineales isla por isla. Los proyectos REDD+ actuales estuvieron ubicados preferencialmente en áreas con una riqueza total de especies y con una riqueza de especies amenazadas más altas pero con densidades de carbono más bajas que en las áreas protegidas y los bosques sin protección. Aunque un cuarto del área total de estos proyectos REDD+ está bajo una presión de deforestación relativamente alta, la mayoría del área REDD+ no lo está. Por lo menos en Indonesia, los proyectos REDD+ de primera generación están ubicados en donde tengan probabilidad de entregar beneficios para la biodiversidad. Sin embargo, si se espera que REDD+ entregue beneficios adicionales para el clima y la biodiversidad, los proyectos necesitarán enfocarse en los bosques con la mayor amenaza de deforestación, lo que tendrá implicaciones de costo para la implementación futura de REDD+. PMID:25864538

Phase Zero Operations for Contingency and Expeditionary Contracting-Keys to Fully Integrating Contracting into Operational Planning and Execution

DTIC Science & Technology

2010-08-02

Cost and Price Analysis & Negotiations (5-2)—DAU CON 217 & CON 218 Certified; MN3318 Contingency Contracting (3-0)—DAU CON 234 Certified; and...MN3315 Advanced Contract Management (4-0)—DAU CON 214 & CON 215 Certified. CDR (Ret) Yoder has recently been published or cited in the following works...certified as the primary guide for all DAU CON 234 course deliveries. Contracting Out Government Procurement Functions: An Analysis (NPS-CM-07-105), E

Impact of Organic and Conventional Systems of Coffee Farming on Soil Properties and Culturable Microbial Diversity

PubMed Central

2016-01-01

A study was undertaken with an objective of evaluating the long-term impacts of organic (ORG) and conventional (CON) methods of coffee farming on soil physical, chemical, biological, and microbial diversity. Electrical conductivity and bulk density were found to increase by 34% and 21%, respectively, in CON compared to ORG system, while water holding capacity was found decreased in both the systems. Significant increase in organic carbon was observed in ORG system. Major nutrients, nitrogen and potassium, levels showed inclination in both ORG and CON system, but the trend was much more pronounced in CON system. Phosphorus was found to increase in both ORG and CON system, but its availability was found to be more with CON system. In biological attributes, higher soil respiration and fluorescein diacetate activity were recorded in ORG system compared to CON system. Higher soil urease activity was observed in CON system, while dehydrogenase activity does not show significant differences between ORG and CON systems. ORG system was found to have higher macrofauna (31.4%), microbial population (34%), and microbial diversity indices compared to CON system. From the present study, it is accomplished that coffee soil under long-term ORG system has better soil properties compared to CON system. PMID:27042378

Impact of Organic and Conventional Systems of Coffee Farming on Soil Properties and Culturable Microbial Diversity.

PubMed

Velmourougane, Kulandaivelu

2016-01-01

A study was undertaken with an objective of evaluating the long-term impacts of organic (ORG) and conventional (CON) methods of coffee farming on soil physical, chemical, biological, and microbial diversity. Electrical conductivity and bulk density were found to increase by 34% and 21%, respectively, in CON compared to ORG system, while water holding capacity was found decreased in both the systems. Significant increase in organic carbon was observed in ORG system. Major nutrients, nitrogen and potassium, levels showed inclination in both ORG and CON system, but the trend was much more pronounced in CON system. Phosphorus was found to increase in both ORG and CON system, but its availability was found to be more with CON system. In biological attributes, higher soil respiration and fluorescein diacetate activity were recorded in ORG system compared to CON system. Higher soil urease activity was observed in CON system, while dehydrogenase activity does not show significant differences between ORG and CON systems. ORG system was found to have higher macrofauna (31.4%), microbial population (34%), and microbial diversity indices compared to CON system. From the present study, it is accomplished that coffee soil under long-term ORG system has better soil properties compared to CON system.

Evaluation of glycerol, a biodiesel coproduct, in grow-finish pig diets to support growth and pork quality.

PubMed

Schieck, S J; Shurson, G C; Kerr, B J; Johnston, L J

2010-12-01

Crossbred pigs (n = 216; BW = 31.3 ± 1.8 kg) were used to determine the effects of long- and short-term feeding of crude glycerol on growth performance, carcass traits, and pork quality of grow-finish pigs. Pigs were blocked by initial BW, and pens within blocks were assigned randomly to 1 of 3 dietary treatments (24 pens; 9 pigs/pen). Dietary treatments were control, a corn-soybean meal-based diet (CON); long-term, CON + 8% glycerol fed throughout the experiment (LT); and short-term, pigs fed CON for the first 6 wk followed by CON + 8% glycerol fed during the last 8 wk of the experiment (ShT). Pigs fed LT had greater (P < 0.05) ADG, whereas pigs fed ShT tended (P < 0.10) to grow faster than CON (CON = 0.962 kg/d, LT = 0.996 kg/d, and ShT = 0.992 kg/d; SE = 0.01). Pigs assigned to LT had greater (P < 0.05) ADFI compared with CON, whereas ShT-fed pigs had similar ADFI to CON (CON = 2.78 kg/d, LT = 2.93 kg/d, and ShT = 2.86 kg/d; SE = 0.03). Gain:feed tended (P < 0.10) to be greater for CON- and ShT-fed pigs compared with LT-fed pigs (CON = 0.346, LT = 0.339, and ShT = 0.346; SE = 0.002). Hot carcass weight was greater (P < 0.05) for LT-fed pigs compared with CON, whereas ShT-fed pigs had HCW similar to both LT- and CON-fed pigs (CON = 94.8 kg, LT = 97.5 kg, and ShT = 96.3 kg; SE = 0.90). Dressing percentage of CON-fed pigs was similar to both LT- and ShT-fed pigs, but LT-fed pigs tended to have greater (P = 0.06) dressing percentage than ShT-fed pigs (CON = 74.5%, LT = 74.9%, and ShT = 74.3%; SE = 0.16). Tenth-rib backfat (P = 0.26) and LM area (P = 0.17) were not affected by dietary treatment. There was a trend (P < 0.10) for LT-fed pigs to have a smaller fat-free lean percentage than CON-fed pigs (CON = 53.1%, LT = 52.26%, and ShT = 52.67%; SE = 0.25). Short-term glycerol feeding increased (P < 0.05) belly firmness compared with CON and had similar belly firmness compared with LT-fed pigs (CON = 29.46°, LT = 35.16°, and ST = 42.08°; SE = 3.07). Dietary treatment had no effect (P > 0.60) on pork quality of loins based on taste panel assessments. Feeding pigs 8% crude glycerol throughout the grow-finish period resulted in a 3% improvement in growth rate and a 2% depression in BW gain efficiency compared with CON diets. Grow-finish pigs fed diets containing 8% crude glycerol during the last 8 wk before slaughter achieved growth performance similar to pigs fed CON diets. Effects of crude glycerol on carcass traits seem to be limited to improvements in belly firmness with short-term feeding of glycerol.

Asociación de la adherencia a la dieta mediterránea al inicio del embarazo y riesgo de gastrosquisis en la descendencia: un estudio de casos-controles

PubMed Central

Cánovas-Conesa, A.; Gomariz-Peñalver, V.; Sánchez-Sauco, M.F.; Vega, D.C. Jaimes; Ortega-García, J.A.; García, M.J. Aranda; Marín, J.L. Delgado; Ascanio, A. Trujillo; Hernández, F. López; Jimenez, J.I. Ruiz; de Paco Matallana, C.; Soldin, O.P.; Solís, M. Sánchez

2016-01-01

Resumen Objetivos El objetivo de este estudio fue estudiar la asociación de la adherencia a la dieta mediterránea materna al inicio del embarazo y el riesgo de gastrosquisis en la descendencia. Métodos Estudio de casos-control. 11 casos incidentes de gastrosquisis en la Región de Murcia de 2007 a 2012 y 34 controles concurrentes. Cuestionario validado de Frecuencia Alimentaria (CFA) sobre la dieta periconcepcional de 98 ítems realizado ‘cara a cara’ en el momento del diagnóstico. Factores confundidores: tabaquismo, expositión a cannabis/marihuana, edad materna y paterna, índice de masa corporal, ingresos económicos y nivel de estudios. Estudio descriptivo y regresión logística multivariable. Resultados Las madres de niños con gastrosquisis son más jóvenes (20,8 años; IC 95% 17,3–24,2) y su dieta tiene un menor aporte calórico, de grasas saturadas y monoinsaturadas y de proteínas que los controles. Odds Ratio (OR) en el modelo multivariable controlado por los factores confundidores: edad materna (años) 0,70 (IC95% 0,51–0,96); ácidos grasos monoinsaturados (oleico, g) 0,79 (IC95% 0,65–0,97) y consumo de vegetales (raciones/semana) 0,70 (IC95% 0,48–1,00). Conclusiones Una dieta materna rica en ácido oleico y productos vegetales podría contribuir a prevenir el riesgo de oclusión vascular de las arterias onfalomesentéricas, disminuyendo el riesgo de gastrosquisis. PMID:23833926

78 FR 62661 - Notice of Lodging of Consent Decree Pursuant to the Clean Air Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-22

... and Natural Resources Division, and should refer to United States v. ConAgra Foods, Inc., and ConAgra... United States of America v. ConAgra Foods, Inc., and ConAgra Grocery Products, LLC, Civil Action No. 2:13-cv-02756. This Decree represents a settlement of claims against the Defendants ConAgra Foods, Inc...

Coagulase-negative staphylococcal bacteraemia in cancer patients. Time to positive culture can distinguish bacteraemia from contamination.

PubMed

Morioka, Shinichiro; Ichikawa, Mika; Mori, Keita; Kurai, Hanako

2018-03-16

Coagulase-negative staphylococci (CoNS) are the most common contaminants of blood cultures, however, we sometimes have difficulties in determining their clinical significance. It is still controversial that there is a significant difference between the contamination group and the true bacteraemia group in the time to positivity (TTP) of blood cultures. We validated the relationship between a TTP and the presence of CoNS bacteraemia in cancer patients by using an objective, non-judgmental definition for CoNS contamination. We retrospectively reviewed 175 sets of blood cultures drawn from 95 patients that yielded CoNS from October 2011 to March 2013. We considered as contamination if an isolate of CoNS was identified in one out of multiple sets of blood cultures. We investigated the TTP, the threshold values and corresponding likelihood ratios to distinguish CoNS bacteraemia from contamination. The median TTP in CoNS bacteraemia group was significantly shorter than that in contamination group (14 h 45 min and 20 h 31 min, respectively, p = .0157). A TTP of ≤16 h had a specificity of 83% for predicting CoNS bacteraemia, and that of >20 h had a sensitivity of 86% for predicting CoNS contamination. We validated that the median TTP in CoNS bacteraemia group was significantly shorter than that in their contamination group, and that a TTP of ≤16 h was associated with CoNS bacteraemia, while that of >20 h was associated with CoNS contamination, if evaluated with an objective, non-judgmental definition for CoNS contamination.

TU-H-CAMPUS-JeP1-05: Dose Deformation Error Associated with Deformable Image Registration Pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Surucu, M; Woerner, A; Roeske, J

Purpose: To evaluate errors associated with using different deformable image registration (DIR) pathways to deform dose from planning CT (pCT) to cone-beam CT (CBCT). Methods: Deforming dose is controversial because of the lack of quality assurance tools. We previously proposed a novel metric to evaluate dose deformation error (DDE) by warping dose information using two methods, via dose and contour deformation. First, isodose lines of the pCT were converted into structures and then deformed to the CBCT using an image based deformation map (dose/structure/deform). Alternatively, the dose matrix from the pCT was deformed to CBCT using the same deformation map,more » and then the same isodose lines of the deformed dose were converted into structures (dose/deform/structure). The doses corresponding to each structure were queried from the deformed dose and full-width-half-maximums were used to evaluate the dose dispersion. The difference between the FWHM of each isodose level structure is defined as the DDE. Three head-and-neck cancer patients were identified. For each patient, two DIRs were performed between the pCT and CBCT, either deforming pCT-to-CBCT or CBCT-to-pCT. We evaluated the errors associated by using either of these pathways to deform dose. A commercially available, Demons based DIR was used for this study, and 10 isodose levels (20% to 105%) were used to evaluate the errors in various dose levels. Results: The prescription dose for all patients was 70 Gy. The mean DDE for CT-to-CBCT deformation was 1.0 Gy (range: 0.3–2.0 Gy) and this was increased to 4.3 Gy (range: 1.5–6.4 Gy) for CBCT-to-CT deformation. The mean increase in DDE between the two deformations was 3.3 Gy (range: 1.0–5.4 Gy). Conclusion: The proposed DDF was used to quantitatively estimate dose deformation errors caused by different pathways to perform DIR. Deforming dose using CBCT-to-CT deformation produced greater error than CT-to-CBCT deformation.« less

Hullborne Hydrofoil Six-Degree of Freedom Motion Prediction Computer Program

DTIC Science & Technology

1976-07-01

UAVEI (7.7) , WAVE2 (797) .!NUEX(1493) .DtIM3(4034) KRN 21 NOE=2 *NO%1 KRN 22 no0 12IzlNON KPZN 23 NIxN0N- I KPN 24 FR(I.1)xEM1 CK,1) KRN 25 FR(192)2-SNE...CON7(J,1)* WAVE2 (1,J)-CON2(NJ,1 )*SOUR2(1,J) KRN III PRA(1,3)=PRA(T,3)+CON1(J,2)*WAVEi CIJ)-CON1(NJ,2)*SOUR1(I.J) KRN 112 PRA(1,4)zPRA(194) .CON2(J,2...8217 WAVE2 (lj)-CON2(NJ,2)*SOUR2(IJJ KRN 113 PPV(1.2)=PRV(192) *CON2(J,1)*SOUR2(I.J) *CON2(NJt1)* WAVE2 (1.J) KRN 115 PRV(193;=PRV(193),CONI(Jt?)4SOUR1(1,J

Needs of Parents in Caring for Their Children in a Pediatric Intensive Care Unit.

PubMed

Valderrama Sanabria, Mery Luz; Muñoz de Rodríguez, Lucy

2016-04-01

This work sought to describe the needs of parents to participate in caring for their children hospitalized in a pediatric intensive care unit (PICU). This is a qualitative study based on the ethno-nursing research method proposed by Leininger. For data collection and analysis, in-depth open interviews were used, along with field notes and enabler guidelines proposed by Leininger: stranger-friend, observation, participation, reflexion, and the Sunrise model. Parents of children hospitalized in a PICU in the city of Tunja (Boyacá, Colombia) participated between February 2012 and October 2013. The needs of parents to care for their children were described in the following themes: clear and timely communication, familiarization with technology, the value of the family, favoring the parent-children interaction during visits, and valuing and respecting generic (folk) knowledge. The study provides knowledge, from the cultural perspective of parents with children hospitalized in PICU, as input to plan and develop care actions with them, according to their own needs.Objetivo.Describir las necesidades de padres para participar del cuidado de sus hijos hospitalizados en la Unidad de Cuidado Intensivo Pediátrico (UCIP). Métodos. Investigación cualitativa basada en el método de la etnoenfermería propuesto por Leininger. Para la recolección y análisis de la información se utilizaron la entrevista abierta a profundidad, las notas de campo y guías facilitadoras propuestas por Leininger: Extraño amigo, Observación, Participación Reflexión y el modelo del sol naciente. Participaron los padres de niños hospitalizados en una UCIP de Tunja (Boyacá, Colombia) entre febrero de 2012 y Octubre de 2013. Resultados. Se describen las necesidades de los padres para cuidar a sus hijos en los siguientes temas: Comunicación clara y oportuna, Familiarización con la Tecnología, El valor de la familia, Favorecer la interacción de padres-hijos durante la visita y Valorar y respetar el conocimiento genérico. Conclusión. Se describieron las necesidades de los padres en el cuidado de sus hijos internados en una UCIP. La enfermera debe tener en cuenta el conocimiento genérico de las personas y respetar las creencias que ellas tengan, con el fin de fortalecer su desempeño como profesional mediante la aplicación de teorías en enfermería.

Medicina integrativa en América: De qué forma se está practicando la medicina integrativa en los centros clínicos en los Estados Unidos

PubMed Central

Horrigan, Bonnie; Lewis, Sheldon; Abrams, Donald I.; Pechura, Constance

2012-01-01

RESUMEN EJECUTIVO El impulso para desarrollar e implementar estrategias de medicina integrativa está enraizado en el deseo de mejorar la atención al paciente. The Bravewell Collaborative, una organización sin ánimo de lucro dedicada a la mejora de la atención sanitaria, define la medicina integrativa como “un enfoque de la medicina que coloca al paciente en el centro y se dirige al conjunto completo de influencias físicas, emocionales, mentales, sociales, espirituales y ambientales que afectan a la salud de la persona. Con una estrategia personalizada que considera las condiciones, necesidades y circunstancias únicas del paciente, utiliza las intervenciones más apropiadas de una variedad de disciplinas científicas para curar la afección y la enfermedad y ayudar a las personas a recobrar y mantener una salud óptima”. En las pasadas dos décadas, se ha documentado un número creciente de centros clínicos que proporcionan medicina integrativa, el número de facultades y escuelas médicas que enseñan estrategias integrativas, el número de investigadores que estudian intervenciones integrativas, y el número de pacientes que solicitan cuidados integrativos. Pero se desconocía si la medicina integrativa se estaba ofreciendo de manera igual, similar, o dispar. Además, mientras que los estudios anteriores se centraban en la prevalencia y el uso de la medicina complementaria o alternativa (MCA) por parte de los pacientes1,2 o de los médicos en hospitales3, enumerando la utilización de terapias MCA individuales, se había recogido muy poca información con respecto a la práctica real de la medicina integrativa que, por definición, trata a la persona en su conjunto. En 2011, The Bravewell Collaborative encargó una encuesta para determinar la forma en que la medicina integrativa se estaba practicando en los Estados Unidos: (1) describiendo las poblaciones de pacientes y las afecciones sanitarias tratadas más habitualmente; (2) definiendo las prácticas y modelos fundamentales de atención; (3) determinando cómo se reembolsaban los servicios; (4) identificando los valores y los principios subyacentes a la atención; y (5) determinando los factores principales que impulsan una implementación satisfactoria.

Interagency Rebuilding Efforts in Iraq: A Case Study of the Rusafa Political District

DTIC Science & Technology

2013-02-26

Cart Seller 18-Aug-2010 $950.00 PRIVSEC NON-CON Cart Seller 18-Aug-2010 $500.00 PRIVSEC NON-CON Embroidery 18-Aug-2010 $22,900.00 PRIVSEC NON-CON...Kindergarten 18-Aug-2010 $11,300.00 PRIVSEC 50 NON-CON Embroidery & Sewing Factory 18-Aug-2010 $21,000.00 PRIVSEC NON-CON Book Shop 18-Aug-2010 $3,204.00

Toward the development of intrafraction tumor deformation tracking using a dynamic multi-leaf collimator

PubMed Central

Ge, Yuanyuan; O’Brien, Ricky T.; Shieh, Chun-Chien; Booth, Jeremy T.; Keall, Paul J.

2014-01-01

Purpose: Intrafraction deformation limits targeting accuracy in radiotherapy. Studies show tumor deformation of over 10 mm for both single tumor deformation and system deformation (due to differential motion between primary tumors and involved lymph nodes). Such deformation cannot be adapted to with current radiotherapy methods. The objective of this study was to develop and experimentally investigate the ability of a dynamic multi-leaf collimator (DMLC) tracking system to account for tumor deformation. Methods: To compensate for tumor deformation, the DMLC tracking strategy is to warp the planned beam aperture directly to conform to the new tumor shape based on real time tumor deformation input. Two deformable phantoms that correspond to a single tumor and a tumor system were developed. The planar deformations derived from the phantom images in beam's eye view were used to guide the aperture warping. An in-house deformable image registration software was developed to automatically trigger the registration once new target image was acquired and send the computed deformation to the DMLC tracking software. Because the registration speed is not fast enough to implement the experiment in real-time manner, the phantom deformation only proceeded to the next position until registration of the current deformation position was completed. The deformation tracking accuracy was evaluated by a geometric target coverage metric defined as the sum of the area incorrectly outside and inside the ideal aperture. The individual contributions from the deformable registration algorithm and the finite leaf width to the tracking uncertainty were analyzed. Clinical proof-of-principle experiment of deformation tracking using previously acquired MR images of a lung cancer patient was implemented to represent the MRI-Linac environment. Intensity-modulated radiation therapy (IMRT) treatment delivered with enabled deformation tracking was simulated and demonstrated. Results: The first experimental investigation of adapting to tumor deformation has been performed using simple deformable phantoms. For the single tumor deformation, the Au+Ao was reduced over 56% when deformation was larger than 2 mm. Overall, the total improvement was 82%. For the tumor system deformation, the Au+Ao reductions were all above 75% and the total Au+Ao improvement was 86%. Similar coverage improvement was also found in simulating deformation tracking during IMRT delivery. The deformable image registration algorithm was identified as the dominant contributor to the tracking error rather than the finite leaf width. The discrepancy between the warped beam shape and the ideal beam shape due to the deformable registration was observed to be partially compensated during leaf fitting due to the finite leaf width. The clinical proof-of-principle experiment demonstrated the feasibility of intrafraction deformable tracking for clinical scenarios. Conclusions: For the first time, we developed and demonstrated an experimental system that is capable of adapting the MLC aperture to account for tumor deformation. This work provides a potentially widely available management method to effectively account for intrafractional tumor deformation. This proof-of-principle study is the first experimental step toward the development of an image-guided radiotherapy system to treat deforming tumors in real-time. PMID:24877798

Toward the development of intrafraction tumor deformation tracking using a dynamic multi-leaf collimator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ge, Yuanyuan; O’Brien, Ricky T.; Shieh, Chun-Chien

Purpose: Intrafraction deformation limits targeting accuracy in radiotherapy. Studies show tumor deformation of over 10 mm for both single tumor deformation and system deformation (due to differential motion between primary tumors and involved lymph nodes). Such deformation cannot be adapted to with current radiotherapy methods. The objective of this study was to develop and experimentally investigate the ability of a dynamic multi-leaf collimator (DMLC) tracking system to account for tumor deformation. Methods: To compensate for tumor deformation, the DMLC tracking strategy is to warp the planned beam aperture directly to conform to the new tumor shape based on real timemore » tumor deformation input. Two deformable phantoms that correspond to a single tumor and a tumor system were developed. The planar deformations derived from the phantom images in beam's eye view were used to guide the aperture warping. An in-house deformable image registration software was developed to automatically trigger the registration once new target image was acquired and send the computed deformation to the DMLC tracking software. Because the registration speed is not fast enough to implement the experiment in real-time manner, the phantom deformation only proceeded to the next position until registration of the current deformation position was completed. The deformation tracking accuracy was evaluated by a geometric target coverage metric defined as the sum of the area incorrectly outside and inside the ideal aperture. The individual contributions from the deformable registration algorithm and the finite leaf width to the tracking uncertainty were analyzed. Clinical proof-of-principle experiment of deformation tracking using previously acquired MR images of a lung cancer patient was implemented to represent the MRI-Linac environment. Intensity-modulated radiation therapy (IMRT) treatment delivered with enabled deformation tracking was simulated and demonstrated. Results: The first experimental investigation of adapting to tumor deformation has been performed using simple deformable phantoms. For the single tumor deformation, the A{sub u}+A{sub o} was reduced over 56% when deformation was larger than 2 mm. Overall, the total improvement was 82%. For the tumor system deformation, the A{sub u}+A{sub o} reductions were all above 75% and the total A{sub u}+A{sub o} improvement was 86%. Similar coverage improvement was also found in simulating deformation tracking during IMRT delivery. The deformable image registration algorithm was identified as the dominant contributor to the tracking error rather than the finite leaf width. The discrepancy between the warped beam shape and the ideal beam shape due to the deformable registration was observed to be partially compensated during leaf fitting due to the finite leaf width. The clinical proof-of-principle experiment demonstrated the feasibility of intrafraction deformable tracking for clinical scenarios. Conclusions: For the first time, we developed and demonstrated an experimental system that is capable of adapting the MLC aperture to account for tumor deformation. This work provides a potentially widely available management method to effectively account for intrafractional tumor deformation. This proof-of-principle study is the first experimental step toward the development of an image-guided radiotherapy system to treat deforming tumors in real-time.« less

Deformation of second and third quantization

NASA Astrophysics Data System (ADS)

Faizal, Mir

2015-03-01

In this paper, we will deform the second and third quantized theories by deforming the canonical commutation relations in such a way that they become consistent with the generalized uncertainty principle. Thus, we will first deform the second quantized commutator and obtain a deformed version of the Wheeler-DeWitt equation. Then we will further deform the third quantized theory by deforming the third quantized canonical commutation relation. This way we will obtain a deformed version of the third quantized theory for the multiverse.

Effect of certificate of need law on emergency department length of stay.

PubMed

Paul, Jomon Aliyas; Ni, Huan; Bagchi, Aniruddha

2014-10-01

The impact of the Certificate of Need (CON) law on Emergency Department (ED) care remains elusive in the academic literature. We study the impact of CON law on ED Length of Stay (LOS). We examine ED LOS to detect any statistically significant difference between CON and non-CON states. We then estimate the effects of CON law on ED LOS by treating CON as an exogenous (endogenous) variable. We find that the CON legislation positively impacts ED care by reducing ED LOS (95% confidence interval [CI] -61.3 to -10.3), and we can't reject the hypothesis that the CON legislation can be treated as an exogenous variable in our model. An increase in the stringency of the CON law (measured by the threshold on equipment expenditure that is subject to a CON review) tends to diminish this positive impact on ED LOS (95% CI 9.9-68.0). The party affiliation of the Governor (95% CI 10.3-37.5), the political environment as a function of the agreement on voting between state senators (95% CI-64.8 to -12.9), proportion of young population (0-17 years) when compared with the elderly (>65 years) (95% CI-2299.7 to -184.1), proportion of population covered by privately purchased insurance (95% CI-819.3 to -59.9), etc., are found to significantly impact ED LOS in a state. This study provides a better understanding of the impact of CON law on ED care, which extends the previous literature that has mainly focused on CON effects on inpatient care. Copyright © 2014 Elsevier Inc. All rights reserved.

AFM study of the plastic deformation behavior of poly-synthetically-twinned (PST) titanium aluminide crystals

NASA Astrophysics Data System (ADS)

Chen, Yali

The plastic deformation behavior of PST TiAl crystals was investigated using AFM techniques to reveal the effects of lamellar structure on the deform mechanisms of two-phase TiAl materials. PST crystals with a nominal composition of Ti52Al48 (atomic percent) were grown by the floating zone method and at various orientations deformed in compression at room temperature. Atomic Force Microscopy (AFM) was employed to investigate the deformation structure on the free surfaces. The deformation of the PST crystals is highly anisotropic and the deformation mechanism changes dramatically with sample orientation. When the angle between the loading axis and the lamellar interfaces is below 20°, the gamma lamellae deform by dislocation slip and twinning on planes oblique to the lamellar interfaces, but the Burgers vectors or the resultant shear vectors are parallel to the lamellar interfaces inside each lamella. When the angle is between 20° and 80° the gamma phase deforms by shear on planes parallel to the lamellar interfaces. Some domains deform by a combination of ordinary dislocation slip and twinning. In the domains where twinning cannot be activated, slip occurs by ordinary dislocations or superdislocations. When the loading axis is nearly perpendicular to the lamellar interfaces ordinary dislocation slip and twinning on slip planes inclined with the lamellar interfaces are dominant and the shear is trans-lamellar. The three deformation modes are termed as A, B and N type deformation modes respectively. In the A type mode the alpha2 lamellae concomitantly deform by prismatic slip. In the other two modes, the alpha2 phase does not deform and acts as strong obstacles to the transfer of deformation. Abundant misfit dislocations are emitted from the lamellar interfaces which is beneficial for the plastic deformation. On the other hand, the lamellar interfaces strongly impede trans-lamellar deformation and channel the deformation inside each lamella. The inhomogeneous coherency stresses at the lamellar interfaces also lead to heterogeneous deformation of PST crystals. The deformation behavior of the lamellar grains produces remarkable strain incompatibility in lamellar polycrystals and deteriorates the deformability.

Increased blood pressure later in life may be associated with perinatal n-3 fatty acid deficiency.

PubMed

Armitage, James A; Pearce, Adrian D; Sinclair, Andrew J; Vingrys, Algis J; Weisinger, Richard S; Weisinger, Harrison S

2003-04-01

Hypertension is a major risk factor for cardiovascular and cerebrovascular disease. Previous work in both animals and humans with high blood pressure has demonstrated the antihypertensive effects of n-3 polyunsaturated fatty acids (PUFA), although it is not known whether these nutrients are effective in preventing hypertension. The predominant n-3 PUFA in the mammalian nervous system, docosahexaenoic acid (DHA), is deposited into synaptic membranes at a high rate during the perinatal period, and recent observations indicate that the perinatal environment is important for the normal development of blood pressure control. This study investigated the importance of perinatal n-3 PUFA supply in the control of blood pressure in adult Sprague-Dawley rats. Pregnant rat dams were fed semisynthetic diets that were either deficient in (DEF) or supplemented with (CON) n-3 PUFA. Offspring were fed the same diets as their mothers until 9 wk; then, half of the rats from each group were crossed over to the opposite diet creating four groups, i.e., CON-CON; CON-DEF; DEF-DEF, DEF-CON. Mean arterial blood pressures (MAP) were measured directly, at 33 wk of age, by cannulation of the femoral artery. The phospholipid fatty acid profile of the hypothalamic region was determined by capillary gas-liquid chromatography. The tissue phospholipid fatty acid profile reflected the diet that the rats were consuming at the time of testing. Both groups receiving DEF after 9 wk of age (i.e., DEF-DEF and CON-DEF) had similar profiles with a reduction in DHA levels of 30%, compared with rats receiving CON (i.e., CON-CON and DEF-CON). DEF-DEF rats had significantly raised MAP compared with all other groups, with differences as great as 17 mm Hg. DEF-CON rats had raised MAP compared with CON-CON rats, and DEF-DEF rats had higher MAP than CON-DEF rats, despite the fact that their respective fatty acid profiles were not different. These findings indicate that inadequate levels of DHA in the perinatal period are associated with altered blood pressure control in later life. The way in which these long-term effects are produced remains to be elucidated.

BFV-BRST analysis of the classical and quantum q-deformations of the sl(2) algebra

NASA Astrophysics Data System (ADS)

Dayi, O. F.

1994-01-01

BFV--BRST charge for q-deformed algebras is not unique. Different constructions of it in the classical as well as in the quantum phase space for the $q$-deformed algebra sl_q(2) are discussed. Moreover, deformation of the phase space without deforming the generators of sl(2) is considered. $\\hbar$-q-deformation of the phase space is shown to yield the Witten's second deformation. To study the BFV--BRST cohomology problem when both the quantum phase space and the group are deformed, a two parameter deformation of sl(2) is proposed, and its BFV-BRST charge is given.

Homogeneous Yang-Baxter deformations as generalized diffeomorphisms

NASA Astrophysics Data System (ADS)

Sakamoto, Jun-ichi; Sakatani, Yuho; Yoshida, Kentaroh

2017-10-01

Yang-Baxter (YB) deformations of string sigma model provide deformed target spaces. We propose that homogeneous YB deformations always lead to a certain class of β-twisted backgrounds and represent the bosonic part of the supergravity fields in terms of the classical r-matrix associated with the YB deformation. We then show that various β-twisted backgrounds can be realized by considering generalized diffeomorphisms in the undeformed background. Our result extends the notable relation between the YB deformations and (non-commuting) TsT transformations. We also discuss more general deformations beyond the YB deformations.

Deformations of the Almheiri-Polchinski model

NASA Astrophysics Data System (ADS)

Kyono, Hideki; Okumura, Suguru; Yoshida, Kentaroh

2017-03-01

We study deformations of the Almheiri-Polchinski (AP) model by employing the Yang-Baxter deformation technique. The general deformed AdS2 metric becomes a solution of a deformed AP model. In particular, the dilaton potential is deformed from a simple quadratic form to a hyperbolic function-type potential similarly to integrable deformations. A specific solution is a deformed black hole solution. Because the deformation makes the spacetime structure around the boundary change drastically and a new naked singularity appears, the holographic interpretation is far from trivial. The Hawking temperature is the same as the undeformed case but the Bekenstein-Hawking entropy is modified due to the deformation. This entropy can also be reproduced by evaluating the renormalized stress tensor with an appropriate counter-term on the regularized screen close to the singularity.

Análise da medição do raio solar em ultravioleta

NASA Astrophysics Data System (ADS)

Saraiva, A. C. V.; Giménez de Castro, C. G.; Costa, J. E. R.; Selhorst, C. L.; Simões, P. J. A.

2003-08-01

A medição acurada do raio solar em qualquer banda do espectro eletromagnético é de relevância na formulação e calibração de modelos da estrutura e atmosfera solar. Esses modelos atribuem emissão do contínuo do Sol calmo em microondas à mesma região da linha Ha do Hell. Apresentamos a medição do raio solar em UV com imagens do EIT (Extreme Ultraviolet Image Telescope) entre 1996 e 2002, no comprimento de onda 30,9 nm (Ha do Hell), que se forma na região de transição/cromosfera solar. A técnica utilizada para o cálculo do raio UV foi baseada na transformada Wavelet B3spline. Fizemos um banco de dados com 1 imagem por dia durante o período citado. Obtivemos como resultado o raio médio da ordem de 975.61" e uma diminuição do mesmo para o período citado variando em média -0,45" /ano. Comparamos estes dados com os valores obtidos pelo ROI (Radio Observatório de Itapetinga) em 22/48 GHz e Nobeyama Radio Heliograph em 17 GHz mostrando que os raios médios são muito próximos o que indica que a região de formação nessas freqüências é a mesma conforme os modelos. Comparamos os resultados também com outros índices de atividade solar.

Orbital shape in intentional skull deformations and adult sagittal craniosynostoses.

PubMed

Sandy, Ronak; Hennocq, Quentin; Nysjö, Johan; Giran, Guillaume; Friess, Martin; Khonsari, Roman Hossein

2018-06-21

Intentional cranial deformations are the result of external mechanical forces exerted on the skull vault that modify the morphology of various craniofacial structures such as the skull base, the orbits and the zygoma. In this controlled study, we investigated the 3D shape of the orbital inner mould and the orbital volume in various types of intentional deformations and in adult non-operated scaphocephaly - the most common type of craniosynostosis - using dedicated morphometric methods. CT scans were performed on 32 adult skulls with intentional deformations, 21 adult skull with scaphocephaly and 17 non-deformed adult skulls from the collections of the Muséum national d'Histoire naturelle in Paris, France. The intentional deformations group included six skulls with Toulouse deformations, eight skulls with circumferential deformations and 18 skulls with antero-posterior deformations. Mean shape models were generated based on a semi-automatic segmentation technique. Orbits were then aligned and compared qualitatively and quantitatively using colour-coded distance maps and by computing the mean absolute distance, the Hausdorff distance, and the Dice similarity coefficient. Orbital symmetry was assessed after mirroring, superimposition and Dice similarity coefficient computation. We showed that orbital shapes were significantly and symmetrically modified in intentional deformations and scaphocephaly compared with non-deformed control skulls. Antero-posterior and circumferential deformations demonstrated a similar and severe orbital deformation pattern resulting in significant smaller orbital volumes. Scaphocephaly and Toulouse deformations had similar deformation patterns but had no effect on orbital volumes. This study showed that intentional deformations and scaphocephaly significantly interact with orbital growth. Our approach was nevertheless not sufficient to identify specific modifications caused by the different types of skull deformations or by scaphocephaly. © 2018 Anatomical Society.

WE-G-BRF-01: Adaptation to Intrafraction Tumor Deformation During Intensity-Modulated Radiotherapy: First Proof-Of-Principle Demonstration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ge, Y; OBrien, R; Shieh, C

2014-06-15

Purpose: Intrafraction tumor deformation limits targeting accuracy in radiotherapy and cannot be adapted to by current motion management techniques. This study simulated intrafractional treatment adaptation to tumor deformations using a dynamic Multi-Leaf Collimator (DMLC) tracking system during Intensity-modulated radiation therapy (IMRT) treatment for the first time. Methods: The DMLC tracking system was developed to adapt to the intrafraction tumor deformation by warping the planned beam aperture guided by the calculated deformation vector field (DVF) obtained from deformable image registration (DIR) at the time of treatment delivery. Seven single phantom deformation images up to 10.4 mm deformation and eight tumor systemmore » phantom deformation images up to 21.5 mm deformation were acquired and used in tracking simulation. The intrafraction adaptation was simulated at the DMLC tracking software platform, which was able to communicate with the image registration software, reshape the instantaneous IMRT field aperture and log the delivered MLC fields.The deformation adaptation accuracy was evaluated by a geometric target coverage metric defined as the sum of the area incorrectly outside and inside the reference aperture. The incremental deformations were arbitrarily determined to take place equally over the delivery interval. The geometric target coverage of delivery with deformation adaptation was compared against the delivery without adaptation. Results: Intrafraction deformation adaptation during dynamic IMRT plan delivery was simulated for single and system deformable phantoms. For the two particular delivery situations, over the treatment course, deformation adaptation improved the target coverage by 89% for single target deformation and 79% for tumor system deformation compared with no-tracking delivery. Conclusion: This work demonstrated the principle of real-time tumor deformation tracking using a DMLC. This is the first step towards the development of an image-guided radiotherapy system to treat deforming tumors in real-time. The authors acknowledge funding support from the Australian NHMRC Australia Fellowship, Cure Cancer Australia Foundation, NHMRC Project Grant APP1042375 and US NIH/NCI R01CA93626.« less

MOBRAL: Un Modelo para la Educacion de Adultos?

ERIC Educational Resources Information Center

Convergence, 1974

1974-01-01

Written in Spanish, the article explains that expanding an adult basic education program, the Brazilian Literacy Movement (MOBRAL), necessitates considering the social orientation of MOBRAL in the context of Brazil and of Latin America as a whole. (AG)

DISE Summary Report (1992)

DTIC Science & Technology

1994-03-01

Specification and Network Time Protocol(NTP) over the Implementation. RFC-o 119, Network OSI Remote Operations Service. RFC- Working Group, September...approximately ISIS implements a powerful model of 94% of the total computation time. distributed computation known as modelo Timing results are

Deformation Recording Process In Polymer-Metal Bilayers And Its Use For Optical Storage

NASA Astrophysics Data System (ADS)

Cornet, Jean A.

1983-11-01

A non-antireflective polymer-metal bilayer structure, encapsulated inside a closed cons-truction/is used for digital data storage in the Thomson-CSF Gigadisc. In this paper, a simple model is presented for microdeformation recording in the medium. This model enables a good understanding of the readout signal as a function of the recording power and leads to some practical consequences. Useful polymers and metallic layers are identified and the disc performance is reported. It is shown that recording using laser diodes can be performed at bit rate up to 14 Mbits.s-1 with a laser power of 7 mW at the disc entry face, in case of a 1200 rpm disc speed. Moreover a working range of 4 mW, as defined by a 3 dB attenuation, is demonstrated. Discs from pilot production exhibit raw bit error rates at the level of 2.10-5. For usual environmental conditions, the disc behaviour is compatible with shelf-and archival life at scale of 10 years. Finally, the processes for both layers deposition and disc construction are easy and cost effective. It is concluded that Giaadisc can successfully enter today the market place.

Variable-intercept panel model for deformation zoning of a super-high arch dam.

PubMed

Shi, Zhongwen; Gu, Chongshi; Qin, Dong

2016-01-01

This study determines dam deformation similarity indexes based on an analysis of deformation zoning features and panel data clustering theory, with comprehensive consideration to the actual deformation law of super-high arch dams and the spatial-temporal features of dam deformation. Measurement methods of these indexes are studied. Based on the established deformation similarity criteria, the principle used to determine the number of dam deformation zones is constructed through entropy weight method. This study proposes the deformation zoning method for super-high arch dams and the implementation steps, analyzes the effect of special influencing factors of different dam zones on the deformation, introduces dummy variables that represent the special effect of dam deformation, and establishes a variable-intercept panel model for deformation zoning of super-high arch dams. Based on different patterns of the special effect in the variable-intercept panel model, two panel analysis models were established to monitor fixed and random effects of dam deformation. Hausman test method of model selection and model effectiveness assessment method are discussed. Finally, the effectiveness of established models is verified through a case study.

Occurrence of oral deformities in larval anurans

USGS Publications Warehouse

Drake, D.L.; Altig, R.; Grace, J.B.; Walls, S.C.

2007-01-01

We quantified deformities in the marginal papillae, tooth rows, and jaw sheaths of tadpoles from 13 population samples representing three families and 11 sites in the southeastern United States. Oral deformities were observed in all samples and in 13.5-98% of the specimens per sample. Batrachochytrium dendrobatidis (chytrid) infections were detected in three samples. There was high variability among samples in the pattern and number of discovered deformities. Pairwise associations between oral structures containing deformities were nonrandom for several populations, especially those with B. dendrobatidis infections or high total numbers of deformities. Comparisons of deformities among samples using multivariate analyses revealed that tadpole samples grouped together by family. Analyses of ordination indicated that three variables, the number of deformities, the number of significant associations among deformity types within populations, and whether populations were infected with B. dendrobatidis, were significantly correlated with the pattern of deformities. Our data indicate that the incidence of oral deformities can be high in natural populations and that phylogeny and B. dendrobatidis infection exert a strong influence on the occurrence and type of oral deformities in tadpoles. ?? by the American Society of Ichthyologists and Herperologists.

Comparative experimental investigation on the actuation mechanisms of ionic polymer–metal composites with different backbones and water contents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Zicai; Chang, Longfei; Wang, Yanjie

2014-03-28

Water-based ionic polymer–metal composites (IPMCs) exhibit complex deformation properties, especially when the water content changes. To explore the general actuation mechanisms, both Nafion and Flemion membranes are used as the polymer backbones. IPMC deformation includes three stages: fast anode deformation, relaxation deformation, and slow anode deformation, which is mainly dependent on the water content and the backbone. When the water content decreases from 21 to 14 wt. %, Nafion–IPMC exhibits a large negative relaxation deformation, zero deformation, a positive relaxation deformation, and a positive steady deformation without relaxation in sequence. Despite the slow anode deformation, Flemion–IPMC also shows a slight relaxation deformation,more » which disappears when the water content is less than 13 wt. %. The different water states are investigated at different water contents using nuclear magnetic resonance spectroscopy. The free water, which decreases rapidly at the beginning through evaporation, is proven to be critical for relaxation deformation. For the backbone, indirect evidence from the steady current response is correlated with the slow anode deformation of Flemion-IPMC. The latter is explained by the secondary dissociation of the weak acid group –COOH. Finally, we thoroughly explain not only the three deformations by swelling but also their evolvement with decreasing water content. A fitting model is also presented based on a multi-diffusion equation to reveal the deformation processes more clearly, the results from which are in good agreement with the experimental results.« less

The distribution of deformation in parallel fault-related folds with migrating axial surfaces: comparison between fault-propagation and fault-bend folding

NASA Astrophysics Data System (ADS)

Salvini, Francesco; Storti, Fabrizio

2001-01-01

In fault-related folds that form by axial surface migration, rocks undergo deformation as they pass through axial surfaces. The distribution and intensity of deformation in these structures has been impacted by the history of axial surface migration. Upon fold initiation, unique dip panels develop, each with a characteristic deformation intensity, depending on their history. During fold growth, rocks that pass through axial surfaces are transported between dip panels and accumulate additional deformation. By tracking the pattern of axial surface migration in model folds, we predict the distribution of relative deformation intensity in simple-step, parallel fault-bend and fault-propagation anticlines. In both cases the deformation is partitioned into unique domains we call deformation panels. For a given rheology of the folded multilayer, deformation intensity will be homogeneously distributed in each deformation panel. Fold limbs are always deformed. The flat crests of fault-propagation anticlines are always undeformed. Two asymmetric deformation panels develop in fault-propagation folds above ramp angles exceeding 29°. For lower ramp angles, an additional, more intensely-deformed panel develops at the transition between the crest and the forelimb. Deformation in the flat crests of fault-bend anticlines occurs when fault displacement exceeds the length of the footwall ramp, but is never found immediately hinterland of the crest to forelimb transition. In environments dominated by brittle deformation, our models may serve as a first-order approximation of the distribution of fractures in fault-related folds.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poplawski, L; Li, T; Chino, J

Purpose: In brachytherapy, structures surrounding the target have the potential to move between treatments and receive unknown dose. Deformable image registration could overcome challenges through dose accumulation. This study uses two possible deformable dose summation techniques and compares the results to point dose summation currently performed in clinic. Methods: Data for ten patients treated with a Syed template was imported into the MIM software (Cleveland, OH). The deformable registration was applied to structures by masking other image data to a single intensity. The registration flow consisted of the following steps: 1) mask CTs so that each of the structures-of-interest hadmore » one unique intensity; 2) perform applicator — based rigid registration; 3) Perform deformable registration; 4) Refine registration by changing local alignments manually; 5) Repeat steps 1 to 3 until desired structure adequately deformed; 5) Transfer each deformed contours to the first CT. The deformed structure accuracy was determined by a dice similarity coefficient (DSC) comparison with the first fraction. Two dose summation techniques were investigated: a deformation and recalculation on the structure; and a dose deformation and accumulation method. Point doses were used as a comparison value. Results: The Syed deformations have DSC ranging from 0.53 to 0.97 and 0.75 and 0.95 for the bladder and rectum, respectively. For the bladder, contour deformation addition ranged from −34.8% to 0.98% and dose deformation accumulation ranged from −35% to 29.3% difference from clinical calculations. For the rectum, contour deformation addition ranged from −5.2% to 16.9% and the dose deformation accumulation ranged from −29.1% to 15.3% change. Conclusion: Deforming dose for summation leads to different volumetric doses than when dose is recalculated on deformed structures, raising concerns about the accuracy of the deformed dose. DSC alone cannot be used to establish the accuracy of a deformation for brachy dose summation purpose.« less

SU-E-J-104: Evaluation of Accuracy for Various Deformable Image Registrations with Virtual Deformation QA Software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, S; Kim, K; Kim, M

Purpose: The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiation treatment planning. We evaluated accuracy of various DIR algorithms using virtual deformation QA software (ImSimQA, Oncology System Limited, UK). Methods: The reference image (Iref) and volume (Vref) was first generated with IMSIMQA software. We deformed Iref with axial movement of deformation point and Vref depending on the type of deformation that are the deformation1 is to increase the Vref (relaxation) and the deformation 2 is to decrease the Vref (contraction) .The deformed image (Idef) and volume (Vdef) were inversely deformed to Iref and Vref usingmore » DIR algorithms. As a Result, we acquired deformed image (Iid) and volume (Vid). The DIR algorithms were optical flow (HS, IOF) and demons (MD, FD) of the DIRART. The image similarity evaluation between Iref and Iid was calculated by Normalized Mutual Information (NMI) and Normalized Cross Correlation (NCC). The value of Dice Similarity Coefficient (DSC) was used for evaluation of volume similarity. Results: When moving distance of deformation point was 4 mm, the value of NMI was above 1.81 and NCC was above 0.99 in all DIR algorithms. Since the degree of deformation was increased, the degree of image similarity was decreased. When the Vref increased or decreased about 12%, the difference between Vref and Vid was within ±5% regardless of the type of deformation. The value of DSC was above 0.95 in deformation1 except for the MD algorithm. In case of deformation 2, that of DSC was above 0.95 in all DIR algorithms. Conclusion: The Idef and Vdef have not been completely restored to Iref and Vref and the accuracy of DIR algorithms was different depending on the degree of deformation. Hence, the performance of DIR algorithms should be verified for the desired applications.« less

Deformation Monitoring and Analysis of Lsp Landslide Based on Gbinsar

NASA Astrophysics Data System (ADS)

Zhou, L.; Guo, J.; Yang, F.

2018-05-01

Monitoring and analyzing the deformation of the river landslide in city to master the deformation law of landslide, which is an important means of landslide safety assessment. In this paper, aiming at the stability of the Liu Sha Peninsula Landslide during its strengthening process after the landslide disaster. Continuous and high precision deformation monitoring of the landslide was carried out by GBInSAR technique. Meanwhile, the two-dimensional deformation time series pictures of the landslide body were retrieved by the time series analysis method. The deformation monitoring and analysis results show that the reinforcement belt on the landslide body was basically stable and the deformation of most PS points on the reinforcement belt was within 1 mm. The deformation of most areas on the landslide body was basically within 4 mm, and the deformation presented obvious nonlinear changes. GBInSAR technique can quickly and effectively obtain the entire deformation information of the river landslide and the evolution process of deformation.

State deregulation and Medicare costs for acute cardiac care.

PubMed

Ho, Vivian; Ku-Goto, Meei-Hsiang

2013-04-01

Past literature suggests that Certificate of Need (CON) regulations for cardiac care were ineffective in improving quality, but less is known about the effect of CON on patient costs. We analyzed Medicare data for 1991-2002 to test whether states that dropped CON experienced changes in costs or reimbursements for coronary artery bypass graft (CABG) surgery or percutaneous coronary interventions. We found that states that dropped CON experienced lower costs per patient for CABG but not for percutaneous coronary intervention. Average Medicare reimbursement was lower for both procedures in states that dropped CON. The cost savings from removing CON regulations slightly exceed the total fixed costs of new CABG facilities that entered after deregulation. Assuming continued cost savings past 2002, the savings from deregulating CABG surgery outweigh the fixed costs of new entry. Thus, CON regulations for CABG may not be justified in terms of either improving quality or controlling cost growth.

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.300 - Chili con carne.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Chili con carne. 319.300 Section 319.300 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Products § 319.300 Chili con carne. “Chili con carne” shall contain not less than 40 percent of meat...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

Concanavalin A: A potential anti-neoplastic agent targeting apoptosis, autophagy and anti-angiogenesis for cancer therapeutics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Wen-wen; Yu, Jia-ying; Xu, Huai-long

2011-10-22

Highlights: {yields} ConA induces cancer cell death targeting apoptosis and autophagy. {yields} ConA inhibits cancer cell angiogenesis. {yields} ConA is utilized in pre-clinical and clinical trials. -- Abstract: Concanavalin A (ConA), a Ca{sup 2+}/Mn{sup 2+}-dependent and mannose/glucose-binding legume lectin, has drawn a rising attention for its remarkable anti-proliferative and anti-tumor activities to a variety of cancer cells. ConA induces programmed cell death via mitochondria-mediated, P73-Foxo1a-Bim apoptosis and BNIP3-mediated mitochondrial autophagy. Through IKK-NF-{kappa}B-COX-2, SHP-2-MEK-1-ERK, and SHP-2-Ras-ERK anti-angiogenic pathways, ConA would inhibit cancer cell survival. In addition, ConA stimulates cell immunity and generates an immune memory, resisting to the same genotypic tumor.more » These biological findings shed light on new perspectives of ConA as a potential anti-neoplastic agent targeting apoptosis, autophagy and anti-angiogenesis in pre-clinical or clinical trials for cancer therapeutics.« less

Low-frequency electrotherapy for female patients with detrusor underactivity due to neuromuscular deficiency.

PubMed

Xu, Dan-Feng; Zhang, Shen; Wang, Cun-Zhou; Li, Jun; Qu, Chuang-Yu; Cui, Xin-Gang; Zhao, Sheng-Jia

2012-08-01

The aim of the study was to assess the efficacy of low-frequency electrotherapy (LFE) for female patients with early-stage detrusor underactivity (DUA) due to neuromuscular deficiency. A total of 102 female patients were divided randomly into four groups: LFE-NC (normal compliance), LFE-LC (low compliance), CON (control)-NC and CON-LC. Patients in the LFE-NC and LFE-LC groups received LFE, and those in the CON-NC and CON-LC groups received conservative treatment. Urodynamic evaluation was performed before and after treatment. After treatment, 82 % of the LFE-NC regained detrusor contractility, whereas only 2 (8 %) of the CON-NC had normal detrusor contraction. None of LFE-LC or CON-LC regained detrusor contractility (p < 0.01). The per cent of LFE-NC who relied on catheterization for bladder emptying decreased by 43 % (p < 0.01). Those in the LFE-LC, CON-NC and CON-LC groups decreased by only 4, 12 or 0 % (p > 0.05). LFE was more effective for DUA patients with normal compliance; these patients benefited from LFE, but DUA patients with low compliance did not.

Global synthesis of volcano deformation: Results of the Volcano Deformation Task Force

NASA Astrophysics Data System (ADS)

Pritchard, M. E.; Jay, J.; Biggs, J.; Ebmeier, S. K.; Delgado, F.

2013-12-01

Ground deformation in volcanic regions is being observed more frequently -- the number of known deforming volcanoes has increased from 44 in 1997 to more than 210 in 2013 thanks in large part thanks to the availability of satellite InSAR observations. With the launch of new SAR satellites in the coming years devoted to global deformation monitoring, the number of well-studied episodes of volcano deformation will continue to increase. But evaluating the significance of the observed deformation is not always straightforward -- how often do deformation episodes lead to eruption? Are there certain characteristics of the deformation or the volcano that make the linkage between deformation and eruption more robust -- for example the duration or magnitude of the ground deformation and/or the composition and tectonic setting of the volcano? To answer these questions, a global database of volcano deformation events is needed. Recognizing the need for global information on volcano deformation and the opportunity to address it with InSAR and other techniques, we formed the Volcano Deformation Database Task force as part of Global Volcano Model. The three objectives of our organization are: 1) to compile deformation observations of all volcanoes globally into appropriate formats for WOVOdat and the Global Volcanism Program of the Smithsonian Institution. 2) document any relation between deformation events and eruptions for the Global assessment of volcanic hazard and risk report for 2015 (GAR15) for the UN. 3) to better link InSAR and other remote sensing observations to volcano observatories. We present the first results from our global study of the relation between deformation and eruptions, including case studies of particular eruptions. We compile a systematically-observed catalog of >500 volcanoes with observation windows up to 20 years. Of 90 volcanoes showing deformation, 40 erupted. The positive predictive value (PPV = 0.44) linking deformation and eruption on this timescale indicates ';strong' evidential worth. The negative predictive value (NPV = 0.94) linking non-deformation with non-eruption, is even stronger. But, linking individual deformation events to eruptions is unreliable with existing InSAR data that are rarely available in the critical days to weeks before the eruption of a volcano that has been dormant for decades to millenia. For example, while ground deformation was observed before the 2011 eruptions of Cordon Caulle and Cerro Hudson (both in Chile), the observations were too infrequent to see any change in the pattern or rate of deformation before the eruptions. Before 2011, Cordon Caulle and Cerro Hudson both erupted in the 20th century, but the 2008 eruption of Chaiten (also in Chile) was preceded by centuries of dormancy and still had no measured precursory deformation up to two weeks before eruption. New InSAR missions with more frequent observations along with ground observations from tiltmeters and GPS are essential to constrain whether there is a reliable deformation signal before eruption.

The Universe in a Box: Introduction to the Study of Astronomy in the Initial Formation of Physics Teachers. (Spanish Title: El Universo Representado en Una Caja: Introducción al Estudio de la Astronomía en la Formación Inicial de Profesores de Física.) O Universo Representado em Uma Caixa: Introdução ao Estudo da Astronomia NA Formação Inicial de Professores de Física

NASA Astrophysics Data System (ADS)

Longhini, Marcos Daniel

2009-07-01

This is a report of an activity of introduction to the study of Astronomy developed with a group of future Physics teachers at a Brazilian public university. Such activity had the goal of giving privileged emphasis to notions of spatiality, alternative conceptions of the participants and the process of interaction among peers, and consisted of the representation, in a three dimensional space, of the models of the universe that the participants had. The results, which were categorized as miscellaneous, geocentric, heliocentric and acentric models of the universe, were qualitatively analyzed. Analyses of the activity in the perspective of the participants are indicated and additional considerations are made regarding its use as a resource for teaching Astronomy and for teacher training. Este es el informe de una actividad para presentar un estudio introductorio de la Astronomía, desarrollado con una clase de futuros profesores de física en una universidad pública brasileña. Esta actividad tuvo como objetivo centrar las nociones de espacialidad, las concepciones alternativas de los participantes y el proceso de interacción entre pares, y consistió en la representación en un espacio tridimensional, de los modelos del universo que los participantes habían. Los resultados, que se clasificaron en universo miscelania, geocéntrico, heliocéntrico y acentrico, se analizaron cualitativamente. Son identificadas análisis de la actividad por los participantes, e hizo observaciones sobre su uso como recurso para la enseñanza de la astronomía y la formación de docentes. Trata-se do relato de uma atividade de introdução ao estudo da Astronomia, desenvolvida com uma turma de futuros professores de Física, em uma universidade pública brasileira. Tal atividade teve como meta privilegiar noções de espacialidade, as concepções alternativas dos participantes e o processo de interação entre pares e constou da representação, em um espaço tridimensional, dos modelos de universo que os participantes possuíam. Os resultados, que foram categorizados em universo miscelânea, geocêntrico, heliocêntrico e acêntrico, foram analisados qualitativamente. São apontadas as análises da atividade na ótica dos participantes, além de tecidas considerações sobre seu emprego como recurso ao ensino de Astronomia e na formação docente.

Diagnóstico y cinética de plasmas de NxOy y aire a baja presión. Aplicaciones atmosféricas

NASA Astrophysics Data System (ADS)

Tanarro Onrubia, Isabel

Los procesos cinéticos que tienen lugar en plasmas de óxidos de nitrógeno y de aire presentan relevancia en diferentes campos de investigación como son los relativos al control de contaminantes atmosféricos emitidos en procesos de combustión, a su formación en las superficies de las naves supersónicas y los vehículos espaciales al entrar en la atmósfera, o a su presencia en la ionosfera terrestre. En general, los fenómenos que tienen lugar en sistemas tan alejados del equilibrio termodinámico como los plasmas luminiscentes, son capaces de originar determinadas especies intermedias y productos finales de reacción a temperaturas y presiones mucho menores que las de otros procedimientos físico-químicos; y hacen posible reproducir y caracterizar en laboratorio ciertas especies inestables y mecanismos primordiales de la alta atmósfera. Por otra parte, las técnicas de resolución temporal aplicadas a plasmas modulados en amplitud resultan notablemente más sensibles que las medidas estacionarias para estimar la relevancia de los distintos mecanismos elementales o incluso para determinar sus constantes de velocidad. En este trabajo se presenta un estudio espectroscópico y espectrométrico comparativo de plasmas de óxidos de nitrógeno y de aire a baja presión (0.001-1 mbar) generados en descargas de cátodo hueco continuas o moduladas, y se propone un modelo cinético único y relativamente sencillo, que explica satisfactoriamente los comportamientos observados en todos ellos. Dicho modelo se basa en la resolución de un sistema de ecuaciones diferenciales dependientes del tiempo, que incluye los mecanismos elementales de disociación e ionización de los precursores y los productos, reacciones homogéneas entre especies atómicas, iónicas y moleculares, y reacciones heterogéneas. Al abordar estos sistemas, se constata una gran carencia de datos experimentales o teóricos sobre secciones eficaces o constantes de velocidad para las reacciones de disociación e ionización por impacto electrónico a bajas energías (<10 eV). Por consiguiente, en el presente trabajo, se proponen las constantes de reacción para varios de estos procesos. Los mecanismos considerados, así como las especies encontradas en estos plasmas, son muy similares a los que tienen lugar en las regiones D y E de la ionosfera terrestre (˜ 80-150 km de altitud), y su estudio en el laboratorio puede contribuir a la interpretación de los datos obtenidos in situ con satélites y sondas.

Direct measurement of erythrocyte deformability in diabetes mellitus with a transparent microchannel capillary model and high-speed video camera system.

PubMed

Tsukada, K; Sekizuka, E; Oshio, C; Minamitani, H

2001-05-01

To measure erythrocyte deformability in vitro, we made transparent microchannels on a crystal substrate as a capillary model. We observed axisymmetrically deformed erythrocytes and defined a deformation index directly from individual flowing erythrocytes. By appropriate choice of channel width and erythrocyte velocity, we could observe erythrocytes deforming to a parachute-like shape similar to that occurring in capillaries. The flowing erythrocytes magnified 200-fold through microscopy were recorded with an image-intensified high-speed video camera system. The sensitivity of deformability measurement was confirmed by comparing the deformation index in healthy controls with erythrocytes whose membranes were hardened by glutaraldehyde. We confirmed that the crystal microchannel system is a valuable tool for erythrocyte deformability measurement. Microangiopathy is a characteristic complication of diabetes mellitus. A decrease in erythrocyte deformability may be part of the cause of this complication. In order to identify the difference in erythrocyte deformability between control and diabetic erythrocytes, we measured erythrocyte deformability using transparent crystal microchannels and a high-speed video camera system. The deformability of diabetic erythrocytes was indeed measurably lower than that of erythrocytes in healthy controls. This result suggests that impaired deformability in diabetic erythrocytes can cause altered viscosity and increase the shear stress on the microvessel wall. Copyright 2001 Academic Press.

[Not Available].

PubMed

Rojo-Trejo, María Elena; Rangel Peniche, Diana Beatriz; Arellano Jiménez, María Del Rocío; Sabath Silva, Ernesto Francisco

2016-06-30

Introducción: el bajo peso al nacer (BPN) es un factor de riesgo para desarrollar obesidad en la vida adulta.Objetivo: evaluar diferencias en la composición corporal de niños de entre 8 y 10 años de edad con y sin antecedente de BPN.Métodos: fue un estudio observacional, transversal comparativo. Participaron 112 niños (95 con adecuado peso al nacer [APN] y 17 con BPN). Se realizó antropometría (peso, talla, circunferencias de cintura y cadera, pliegue cutáneo de tríceps [PCT] y subescapular [PCSE]).Resultados: se encontró una prevalencia combinada del 41% para sobrepeso y obesidad en ambos grupos de estudio. El porcentaje de grasa corporal total fue menor en las niñas con BPN (no significativo); sin embargo, el indicador PCT-PCSE fue significativamente más alto (p = 0,04) que el de las niñas con APN. En contra de lo esperado, al estratificar según porcentaje de grasa y peso al nacer, se encontró que el grupo con BPN presentó un porcentaje de grasa bajo (p < 0,05) en comparación con el grupo de APN, siendo 6 veces mayor la posibilidad de que un niño con BPN presente porcentaje de grasa total bajo a esta edad.Conclusiones: a estas edades no se encontró mayor porcentaje de grasa en el grupo con BPN en comparación con el de APN; sin embargo, las niñas con BPN presentaron mayor deposición de grasa troncal que las de APN. La deposición de grasa es un indicador que hay que considerar, y no únicamente el índice de masa corporal, en la evaluación nutricia infantil.

Salecan protected against concanavalin A-induced acute liver injury by modulating T cell immune responses and NMR-based metabolic profiles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Qi; Xu, Xi, E-mail: xuxi@njust.edu.cn; Yang,

Salecan, a water-soluble extracellular β-glucan produced by Agrobacterium sp. ZX09, has been reported to exhibit a wide range of biological effects. The aims of the present study were to investigate the protective effect of salecan against Concanavalin A (ConA)-induced hepatitis, a well-established animal model of immune-mediated liver injury, and to search for possible mechanisms. C57BL/6 mice were pretreated with salecan followed by ConA injection. Salecan treatment significantly reduced ConA-induced acute liver injury, and suppressed the expression and secretion of inflammatory cytokines including interferon (IFN)-γ, interleukin (IL)-6 and IL-1β in ConA-induced liver injury model. The high expression levels of chemokines andmore » adhesion molecules such as MIP-1α, MIP-1β, ICAM-1, MCP-1 and RANTES in the liver induced by ConA were also down-regulated after salecan treatment. Salecan inhibited the infiltration and activation of inflammatory cells, especially T cells, in the liver induced by ConA. Moreover, salecan reversed the metabolic profiles of ConA-treated mice towards the control group by partly recovering the metabolic perturbations induced by ConA. Our results suggest the preventive and therapeutic potential of salecan in immune-mediated hepatitis. - Highlights: • Salecan treatment significantly reduced ConA-induced liver injury. • Salecan suppressed the expression and secretion of inflammatory cytokines. • Salecan decreased the expression of chemokines and adhesion molecules in liver. • Salecan inhibited the infiltration and activation of T cells induced by ConA. • Salecan partly recovered the metabolic perturbations induced by ConA.« less

Effect of Maternal Obesity on Fetal Growth and Expression of Placental Fatty Acid Transporters.

PubMed

Ye, Kui; Li, Li; Zhang, Dan; Li, Yi; Wang, Hai Qing; Lai, Han Lin; Hu, Chuan Lai

2017-12-15

To explore the effects of maternal high-fat (HF) diet-induced obesity on fetal growth and the expression of placental nutrient transporters. Maternal obesity was established in rats by 8 weeks of pre-pregnancy fed HF diet, while rats in the control group were fed normal (CON) diet. Diet-induced obesity (DIO) rats and diet-induced obesity-resistant (DIR) rats were selected according to body weight gain over this period. After copulation, the CON rats were divided into two groups: switched to HF diet (CON-HF group) or maintained on the CON diet (CON-CON group). The DIO rats and DIR rats were maintained on the HF diet throughout pregnancy. Pregnant rats were euthanized at day 21 gestation, fetal and placental weights were recorded, and placental tissue was collected. Reverse transcription-polymerase chain reaction was used to determine mRNA expression of placental nutrient transporters. Protein expression was determined by Western blot. Average fetal weight of DIO dams was reduced by 6.9%, and the placentas of CON-HF and DIO dams were significantly heavier than the placentas of CON-CON and DIR dams at day 21 of gestation (p<0.05). The fetal/placental weight ratio of DIO dams was significantly reduced compared with the fetal/placental weight ratio of CON-CON dams (p<0.05). The mRNA expression of GLUT-1 and SNAT-2 were not significantly different between groups. The mRNA and protein expression levels of CD36, FATP-1, and FATP-4 in DIO dams were decreased significantly (p<0.05). Maternal obesity induced by a HF diet led to intrauterine growth retardation and down-regulated the expression of placental fatty acid transporters.

The Columbia Thyroid Eye Disease-Compressive Optic Neuropathy Formula.

PubMed

Callahan, Alison B; Campbell, Ashley A; Oropesa, Susel; Baraban, Aryeh; Kazim, Michael

2018-06-13

Diagnosing thyroid eye disease-compressive optic neuropathy (TED-CON) is challenging, particularly in cases lacking a relative afferent pupillary defect. Large case series of TED-CON patients and accessible diagnostic tools are lacking in the current literature. This study aims to create a mathematical formula that accurately predicts the presence or absence of CON based on the most salient clinical measures of optic neuropathy. A retrospective case series compares 108 patients (216 orbits) with either unilateral or bilateral TED-CON and 41 age-matched patients (82 orbits) with noncompressive TED. Utilizing clinical variables assessing optic nerve function and/or risk of compressive disease, and with the aid of generalized linear regression modeling, the authors create a mathematical formula that weighs the relative contribution of each clinical variable in the overall prediction of CON. Data from 213 orbits in 110 patients derived the formula: y = -0.69 + 2.58 × (afferent pupillary defect) - 0.31 × (summed limitation of ductions) - 0.2 × (mean deviation on Humphrey visual field testing) - 0.02 × (% color plates). This accurately predicted the presence of CON (y > 0) versus non-CON (y < 0) in 82% of cases with 83% sensitivity and 81% specificity. When there was no relative afferent pupillary defect, which was the case in 63% of CON orbits, the formula correctly predicted CON in 78% of orbits with 73% sensitivity and 83% specificity. The authors developed a mathematical formula, the Columbia TED-CON Formula (CTD Formula), that can help guide clinicians in accurately diagnosing TED-CON, particularly in the presence of bilateral disease and when no relative afferent pupillary defect is present.

Physics-based deformable organisms for medical image analysis

NASA Astrophysics Data System (ADS)

Hamarneh, Ghassan; McIntosh, Chris

2005-04-01

Previously, "Deformable organisms" were introduced as a novel paradigm for medical image analysis that uses artificial life modelling concepts. Deformable organisms were designed to complement the classical bottom-up deformable models methodologies (geometrical and physical layers), with top-down intelligent deformation control mechanisms (behavioral and cognitive layers). However, a true physical layer was absent and in order to complete medical image segmentation tasks, deformable organisms relied on pure geometry-based shape deformations guided by sensory data, prior structural knowledge, and expert-generated schedules of behaviors. In this paper we introduce the use of physics-based shape deformations within the deformable organisms framework yielding additional robustness by allowing intuitive real-time user guidance and interaction when necessary. We present the results of applying our physics-based deformable organisms, with an underlying dynamic spring-mass mesh model, to segmenting and labelling the corpus callosum in 2D midsagittal magnetic resonance images.

Deformation measurement for a rotating deformable lap based on inverse fringe projection

NASA Astrophysics Data System (ADS)

Liao, Min; Zhang, Qican

2015-03-01

The active deformable lap (also namely stressed lap) is an efficient polishing tool in optical manufacturing. To measure the dynamic deformation caused by outside force on a deformable lap is important and helpful to the opticians to ensure the performance of a deformable lap as expected. In this paper, a manual deformable lap was designed to simulate the dynamic deformation of an active stressed lap, and a measurement system was developed based on inverse projected fringe technique to restore the 3D shape. A redesigned inverse fringe has been projected onto the surface of the measured lap, and the deformations of the tested lap become much obvious and can be easily and quickly evaluated by Fourier fringe analysis. Compared with the conventional projection, this technique is more obvious, and it should be a promising one in the deformation measurement of the active stressed lap in optical manufacturing.

PubMed

Alvarez Padilla, Facundo Nicolás; Schiavoni, Emiliano Nestor; Bustos, Mario Eduardo Francisco

2018-04-20

INTRODUCCIONEl derrame pleural neoplásico (DPN) implica una enfermedad oncológica avanzada. La biopsia pleural por cirugía torácica endoscópica permite el diagnóstico en más del 90% de los casos y la instrumentación del espacio pleural complicado, mejorando los resultados de la técnica.MATERIAL Y METODOSe realizó un análisis retrospectivo de pacientes con DPN operados para la realización de una pleurodesis química con talco. Se formaron dos grupos, uno con derrame pleural neoplásico complicado (DPNC) y otro con derrame pleural neoplásico no complicado (DPNNC). En el grupo con DPNC se realizó "maniobras de liberación - expansión". Se compararon las variables entre ambos grupos para el análisis pertinente.RESULTADOSSe analizaron 28 pacientes con DPN tratados con pleurodesis química por cirugía torácica endoscópica. La edad promedio fue de 62,64 años. El compromiso pleural por patología mamaria fue la forma más frecuente (46,4%). No se hubo diferencia en cuanto a complicaciones (p= 0,31) y riesgo de defunción a los 30 días (p=1,09) con el manejo agresivo del espacio pleural. La demora en la indicación de pleurodesis se relacionó con un mayor índice de complicaciones (p=0,002) y mayor probabilidad de defunción dentro de los 30 días (p=0,008). La mayoría de pacientes se reinsertó a sus tareas diarias, con buena tolerancia a la disnea luego del procedimiento.  CONCLUSIONEn los pacientes con DPNC, las "maniobras de liberación - expansión pulmonar" descriptas, aumentarían las chances de mejorar los resultados con bajo riesgo. La pleurodesis química temprana mejora la calidad de vida de los pacientes portadores de un DPN.

TH-B-204-01: Real-Time Tracking with Implanted Markers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Q.

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRImore » compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant for Accuray planning service.« less

TH-B-204-03: TG-199: Implanted Markers for Radiation Treatment Verification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Z.

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRImore » compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant for Accuray planning service.« less

TH-B-204-02: Application of Implanted Markers in Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, S.

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRImore » compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant for Accuray planning service.« less

TH-B-204-00: Implanted Markers for Radiation Therapy and TG 199 Update

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Implanted markers as target surrogates have been widely used for treatment verification, as they provide safe and reliable monitoring of the inter- and intra-fractional target motion. The rapid advancement of technology requires a critical review and recommendation for the usage of implanted surrogates in current field. The symposium, also reporting an update of AAPM TG 199 - Implanted Target Surrogates for Radiation Treatment Verification, will be focusing on all clinical aspects of using the implanted target surrogates for treatment verification and related issues. A wide variety of markers available in the market will be first reviewed, including radiopaque markers, MRImore » compatible makers, non-migrating coils, surgical clips and electromagnetic transponders etc. The pros and cons of each kind will be discussed. The clinical applications of implanted surrogates will be presented based on different anatomical sites. For the lung, we will discuss gated treatments and 2D or 3D real-time fiducial tracking techniques. For the prostate, we will be focusing on 2D-3D, 3D-3D matching and electromagnetic transponder based localization techniques. For the liver, we will review techniques when patients are under gating, shallow or free breathing condition. We will review techniques when treating challenging breast cancer as deformation may occur. Finally, we will summarize potential issues related to the usage of implanted target surrogates with TG 199 recommendations. A review of fiducial migration and fiducial derived target rotation in different disease sites will be provided. The issue of target deformation, especially near the diaphragm, and related suggestions will be also presented and discussed. Learning Objectives: Knowledge of a wide variety of markers Knowledge of their application for different disease sites Understand of issues related to these applications Z. Wang: Research funding support from Brainlab AG Q. Xu: Consultant for Accuray; Q. Xu, I am a consultant for Accuray planning service.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fullerton, Aaron M., E-mail: fuller22@msu.edu; Roth, Robert A., E-mail: rothr@msu.edu; Ganey, Patricia E., E-mail: ganey@msu.edu

Inflammation plays a major role in immune-mediated liver injury, and exposure to environmental pollutants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter the inflammatory response as well as affect immune cell activity. In this study, we tested the hypothesis that TCDD pretreatment exacerbates hepatotoxicity in a murine model of immune-mediated liver injury induced by concanavalin A (Con A) administration. Mice were pretreated with 30 μg/kg TCDD or vehicle control on day zero and then given either Con A or saline intravenously on day four. Mice treated with TCDD did not develop liver injury; however, TCDD pretreatment increased liver injurymore » resulting from moderate doses of Con A (4–10 mg/kg). TCDD-pretreated mice had altered plasma concentrations of inflammatory cytokines, including interferon gamma (IFNγ), and TCDD/Con A-induced hepatotoxicity was attenuated in IFNγ knockout mice. At various times after treatment, intrahepatic immune cells were isolated, and expression of cell activation markers as well as cytolytic proteins was determined. TCDD pretreatment increased the proportion of activated natural killer T (NKT) cells and the percent of cells expressing Fas ligand (FasL) after Con A administration. In addition FasL knockout mice and mice treated with CD18 antiserum were both protected from TCDD/Con A-induced hepatotoxicity, suggesting a requirement for direct cell–cell interaction between effector immune cells and parenchymal cell targets in the development of liver injury from TCDD/Con A treatment. In summary, exposure to TCDD increased NKT cell activation and exacerbated immune-mediated liver injury induced by Con A through a mechanism involving IFNγ and FasL expression. -- Highlights: ► TCDD pretreatment sensitizes mice to Con A-induced hepatotoxicity. ► TCDD pretreatment increased concentration of IFNγ in plasma after Con A. ► Con A-induced activation of NKT cells was increased by TCDD pretreatment. ► FasL-positive NKT cells increased with TCDD pretreatment versus Con A alone. ► IFNγ and FasL are critical to the development of liver injury from TCDD/Con A.« less

Dietary Methionine Restriction Alleviates Hyperglycemia in Pigs with Intrauterine Growth Restriction by Enhancing Hepatic Protein Kinase B Signaling and Glycogen Synthesis.

PubMed

Ying, Zhixiong; Zhang, Hao; Su, Weipeng; Zhou, Le; Wang, Fei; Li, Yue; Zhang, Lili; Wang, Tian

2017-10-01

Background: Individuals with intrauterine growth restriction (IUGR) are prone to developing type 2 diabetes mellitus (T2DM). Dietary methionine restriction (MR) improves insulin sensitivity and glucose homeostasis in individuals with normal birth weight (NBW). Objective: This study investigated the effects of MR on plasma glucose concentration and hepatic and muscle glucose metabolism in pigs with IUGR. Methods: Thirty female NBW and 60 same-sex spontaneous IUGR piglets (Landrace × Yorkshire) were selected. After weaning (day 21), the piglets were fed diets with adequate methionine (NBW-CON and IUGR-CON) or 30% less methionine (IUGR-MR) ( n = 6). At day 180, 1 pig with a body weight near the mean of each replication was selected for biochemical analysis. Results: The IUGR-CON group showed 41.6%, 68.6%, and 67.1% higher plasma glucose concentration, hepatic phosphoenolpyruvate carboxykinase activity, and glucose-6-phosphatase activity, respectively, than the NBW-CON group ( P < 0.05). Muscle glycogen content and glycogen synthase activity were 36.9% and 38.8% lower, respectively, in the IUGR-CON than the NBW-CON group ( P < 0.05), respectively, and there was decreased hepatic and muscle protein kinase B phosphorylation in the IUGR-CON group ( P < 0.05). Compared with the IUGR-CON pigs, the IUGR-MR pigs had 28.7% lower plasma glucose concentrations ( P < 0.05), which were similar to those of the NBW-CON pigs ( P ≥ 0.05). The hepatic glycogen content and glycogen synthase activity of the IUGR-MR pigs were 62.9% and 50.8% higher than those of the IUGR-CON pigs ( P < 0.05) and 53.5% and 84.3% higher than the NBW-CON pigs ( P < 0.05), respectively. The IUGR-MR pigs' hepatic and muscle protein kinase B phosphorylation was higher than that of the IUGR-CON pigs ( P < 0.05) and similar to that of the NBW-CON pigs ( P ≥ 0.05). Conclusion: MR attenuates hyperglycemia in IUGR pigs by enhancing hepatic protein kinase B signaling and glycogen synthesis, implying a potential nutritional strategy to prevent type 2 diabetes mellitus in IUGR offspring. © 2017 American Society for Nutrition.

Propiedades biomecánicas de la membrana limitante interna tras recibir tratamiento intravítreo con ocriplasmina.

PubMed

Vielmuth, Franziska; Schumann, Ricarda G; Spindler, Volker; Wolf, Armin; Scheler, Renate; Mayer, Wolfgang J; Henrich, Paul B; Haritoglou, Christos

2017-01-01

Objetivo: Evaluar la rigidez de la membrana limitante interna (MLI) humana y evaluar los posibles cambios de las propiedades mecánicas tras administrar una inyección intravítrea de ocriplasmina para tratar la tracción vitreomacular. Métodos: Este estudio se compone de una serie de casos intervencionales y comparativos de 12 muestras de MLI extraídas mediante cirugía y obtenidas de forma consecutiva de 9 ojos de 9 pacientes después de someterse sin éxito a vitreólisis farmacológica con ocriplasmina. Durante el mismo periodo de tiempo, 16 muestras de otros 13 ojos sin tratamiento con ocriplasmina se obtuvieron mediante vitrectomía y sirvieron como controles. Todos los pacientes presentaron agujeros maculares o tracción vitreomacular y se sometieron a vitrectomía con disección de la MLI tanto con tinción con azul brillante (AB) como sin ella. Todas las muestras se analizaron con un microscopio de fuerza atómica con imágenes de las regiones de 25 × 25 μm. En todas las muestras, se analizaron tanto la parte de la retina como la del vítreo de la MLI. Resultados: La microscopia de fuerza atómica no reveló diferencias significativas en cuanto a elasticidad de las muestras de MLI extraídas de ojos con o sin tratamiento con ocriplasmina. Las áreas onduladas de la parte de la retina presentaron una mayor rigidez que la parte del vítreo de la MLI. La cartografía topográfica tanto de la parte del vítreo como de la retina de la MLI no mostró ninguna alteración aparente de la morfología en ojos tratados con ocriplasmina en comparación con los ojos no tratados. La tinción con azul brillante conllevó un aumento de la rigidez tisular. Conclusiones: Las inyecciones intravítreas de ocriplasmina no varían las propiedades biomecánicas de la MLI humana. No existen pruebas de un posible efecto enzimático que interfiera con la rigidez de esta membrana basal. © 2017 S. Karger AG, Basel.

Thin-skinned deformation of sedimentary rocks in Valles Marineris, Mars

USGS Publications Warehouse

Metz, Joannah; Grotzinger, John P.; Okubo, Chris; Milliken, Ralph

2010-01-01

Deformation of sedimentary rocks is widespread within Valles Marineris, characterized by both plastic and brittle deformation identified in Candor, Melas, and Ius Chasmata. We identified four deformation styles using HiRISE and CTX images: kilometer-scale convolute folds, detached slabs, folded strata, and pull-apart structures. Convolute folds are detached rounded slabs of material with alternating dark- and light-toned strata and a fold wavelength of about 1 km. The detached slabs are isolated rounded blocks of material, but they exhibit only highly localized evidence of stratification. Folded strata are composed of continuously folded layers that are not detached. Pull-apart structures are composed of stratified rock that has broken off into small irregularly shaped pieces showing evidence of brittle deformation. Some areas exhibit multiple styles of deformation and grade from one type of deformation into another. The deformed rocks are observed over thousands of kilometers, are limited to discrete stratigraphic intervals, and occur over a wide range in elevations. All deformation styles appear to be of likely thin-skinned origin. CRISM reflectance spectra show that some of the deformed sediments contain a component of monohydrated and polyhydrated sulfates. Several mechanisms could be responsible for the deformation of sedimentary rocks in Valles Marineris, such as subaerial or subaqueous gravitational slumping or sliding and soft sediment deformation, where the latter could include impact-induced or seismically induced liquefaction. These mechanisms are evaluated based on their expected pattern, scale, and areal extent of deformation. Deformation produced from slow subaerial or subaqueous landsliding and liquefaction is consistent with the deformation observed in Valles Marineris.

Numerical Investigations on Aerodynamic Forces of Deformable Foils in Hovering Motions

NASA Astrophysics Data System (ADS)

Zhao, Yong; Yin, Zhen; Su, Xiaohui; Zhang, Jiantao; Cao, Yuanwei

2017-09-01

The aerodynamic effects of wing deformation for hover flight are numerically investigated by a two-dimensional finite-volume (FV) Arbitrary Langrangian Eulerian (ALE) Navier-Stokes solver. Two deformation models are employed to study these effects in this paper, which are a full deformation model and a partial deformation one. Attentions are paid to the generation and development of leading edge vortex (LEV) and trailing edge vortex (TEV) which may illustrate the differences of lift force generation mechanisms from those of rigid wings. Moreover, lift coefficient Cl, drag coefficient Cd, and figure of merit, as well as energy consumption in hovering motion for different deformation foil models, are also studied. The results show that the deformed amplitude, 0.1*chord, among the cases simulated is an optimized camber amplitude for full deformation. The results obtained from the partial deformation foil model show that both Cl and Cd decrease with the increase of camber amplitude. It is found that the effect of deformation in the partial deformation model does not enhance lift force due to unfavorable camber. But TEV is significantly changed by the local AOA due to the deformation of the foil. Introduction.

Autofrecuencias de las ecuaciones de Helmholtz y Liouville para un modelo de tierra tipo Jeffreys simplificado.

NASA Astrophysics Data System (ADS)

Sevilla, M. J.; González-Camacho, A.

The authors obtain expressions for the free frequencies of polar motion for an ellipsoidal, rotating and perturbed earth model constituted by an elastic mantle with an homogeneous liquid core of additional simple motion.

48 CFR 301.608 - Training requirements for purchase cardholders, Approving Officials, and Agency/Organization...

Code of Federal Regulations, 2010 CFR

2010-10-01

... REGULATION SYSTEM Career Development, Contracting Authority, and Responsibilities 301.608 Training... new DPA. b CON 237, CON 100, and CON 110 are available at the DAU Web site at http://www.dau.mil/registrar/enroll.asp. CON 100 is also offered through HHS University (see Web site at: http://learning.hhs...

Perceptional gaps among women, husbands and family members about intentions for birthplace: a cross-sectional study.

PubMed

Shimpuku, Yoko; Madeni, Frida Elikana; Horiuchi, Shigeko; Leshabari, Sebalda Charles

2017-01-30

women are more likely to give birth at a health facility when their families agree with the birthplace. However, in rural areas of Tanzania, women are often marginalized from decision-making. This study predicted birthplace intention and identified factors to reduce perceptional gaps among pregnant women, husbands and family members. explanatory cross-sectional survey was conducted in three villages in North Eastern Tanzania. Participants were 138 pregnant women and their families who answered the Birth Intention Questionnaire (BIQ), measuring knowledge, attitude, perceived behavioral control, subjective norms and intention for birthplace. Descriptive analysis, ANOVA, Chi-square, and multiple linear regression was used to analyze the data. the regression model showed that knowledge, perceived behavioral control, and subjective norms predicted intention for birthplace (R2 = .28). While 81% of pregnant women thought their husbands were decision-makers for their birth, only 38% of husbands and 37% of family members agreed. Pregnant women had significantly lower scores on the item "I will prepare for childbirth with my family" compared with husbands (p < .01) and other family members (p < .001). providing evidence-based birth preparation and reducing the identified perceptual gaps may enhance women's intention to deliver at health facilities. as mulheres são mais propensas a dar à luz em um centro de saúde quando suas famílias estão de acordo com o local de nascimento. No entanto, nas áreas rurais da Tanzânia, as mulheres são muitas vezes marginalizadas do processo de decisão. Este estudo fez previsoes de intenção para o local do parto e fatores para reduzir as lacunas de percepção entre as mulheres grávidas, seus maridos e familiares identificados. estudo transversal explicativo realizado em três aldeias no nordeste da Tanzânia. Os participantes foram 138 mulheres grávidas e suas famílias que responderam ao Questionário de Intenção sobre Parto (BIQ), medindo o conhecimento, atitude, percepcão de controle comportamental, normas subjetivas e intenção para lugar de parto. Análise descritivas, ANOVA, Qui-quadrado e regressão linear múltipla foram utilizados para analisar os dados. o modelo de regressão mostrou que o conhecimento, percepcão de controle comportamental e normas subjetivas previram intenção de lugar de parto (R2 = 0,28). Enquanto 81% das mulheres grávidas pensavam que seus maridos eram os decisores para seu parto, apenas 38% dos maridos e 37% dos membros da família concordaram. As mulheres grávidas tiveram escores significativamente mais baixos sobre o item "Vou me preparar para o parto com a minha família", em comparação com os maridos (p < 0,01) e outros membros da família (p < 0,001). Proporcionar preparação para o parto baseada em evidencias e a redução das lacunas de percepção identificadas podem melhorar a intenção das mulheres para dar à luz em unidades de saúde. las mujeres son más propensas a dar a luz en un centro de salud cuando sus familias están de acuerdo con el lugar de parto. Sin embargo, en las zonas rurales de Tanzania, las mujeres son a menudo marginadas de la toma de decisiones. Este estudio predijo la intención del lugar de parto y los factores identificados para reducir la brecha de percepción entre las mujeres embarazadas, esposos y miembros de la familia. encuesta transversal explicativa llevada a cabo en tres aldeas en el noreste de Tanzania. Los participantes fueron 138 mujeres embarazadas y sus familias, que respondieron al Cuestionario sobre Intención del Parto (BIQ), que mide el conocimiento, la actitud, percepción de control del comportamiento, las normas subjetivas y la intención de lugar de parto. Se utilizaron análisis descriptivo, ANOVA, Chi-cuadrado y regresión lineal múltiple para analizar los datos. el modelo de regresión mostró que el conocimiento, la percepción de control del comportamiento, y las normas subjetivas predijeron la intencion del lugar de parto (R2 = 0,28). Mientras que el 81% de las mujeres embarazadas pensaba que sus maridos estaban encargados de tomar decisiones para el nacimiento, sólo el 38% de los esposos y el 37% de los miembros de la familia estuvieron de acuerdo. Las mujeres embarazadas tenían puntuaciones significativamente más bajas en el tema "Me prepararé para el parto con mi familia", en comparación con los maridos (p < 0,01) y otros miembros de la familia (p < 0,001). proporcionar la preparación al parto basada en la evidencia y reducir las brechas de percepción identificadas pueden mejorar intención de las mujeres a dar a luz en centros de salud.

Interpretation of tracer tests performed in fractured rock of the Lange Bramke basin, Germany

NASA Astrophysics Data System (ADS)

Maloszewski, Piotr; Herrmann, Andreas; Zuber, Andrzej

Two multitracer tests performed in one of the major cross-fault zones of the Lange Bramke basin (Harz Mountains, Germany) confirm the dominant role of the fault zone in groundwater flow and solute transport. Tracers having different coefficients of molecular diffusion (deuterium, bromide, uranine, and eosine) yielded breakthrough curves that can only be explained by a model that couples the advective-dispersive transport in the fractures with the molecular diffusion exchange in the matrix. For the scale of the tests (maximum distance of 225m), an approximation was used in which the influence of adjacent fractures is neglected. That model yielded nearly the same rock and transport parameters for each tracer, which means that the single-fracture approximation is acceptable and that matrix diffusion plays an important role. The hydraulic conductivity of the fault zone obtained from the tracer tests is about 1.5×10-2m/s, whereas the regional hydraulic conductivity of the fractured rock mass is about 3×10-7m/s, as estimated from the tritium age and the matrix porosity of about 2%. These values show that the hydraulic conductivity along the fault is several orders of magnitude larger than that of the remaining fractured part of the aquifer, which confirms the dominant role of the fault zones as collectors of water and conductors of fast flow. Résumé Deux multitraçages ont été réalisés dans l'une des zones principales de failles du bassin de Lange Bramke (massif du Harz, Allemagne); les résultats confirment le rôle prédominant de la zone de failles pour l'écoulement souterrain et le transport de soluté. Les traceurs, possédant des coefficients de diffusion différents (deutérium, bromure, uranine et éosine), ont fourni des courbes de restitution qui ne peuvent être expliquées que par un modèle qui associe un transport advectif-dispersif dans les fractures à un échange par diffusion moléculaire dans la matrice. A l'échelle des expériences (distance maximale de 225m), l'influence des fractures adjacentes a été négligée. Ce modèle a fourni pour chaque traceur pratiquement les mêmes paramètres pour la roche et le transport, ce qui signifie que l'approximation de la fracture unique est acceptable et que la diffusion dans la matrice joue un rôle important. La conductivité hydraulique de la zone de faille fournie par les traçages est d'environ 1,5×10-2m/s, alors que la conductivité hydraulique régionale de la roche fracturée dans son ensemble est de l'ordre de 3×10-7m/s, selon l'estimation tirée des âges tritium et de la porosité de la matrice d'environ 2%. Ces valeurs montrent que la conductivité hydraulique le long de la faille est supérieure de plusieurs ordres de grandeur à celle de la partie fracturée restante de l'aquifère, ce qui confirme le rôle prédominant joué par les zones de failles comme drains de l'eau et comme axes d'écoulement rapide. Resumen Dos ensayos con múltiples trazadores realizados en una de las zonas más fracturadas de la cuenca de Lange Bramke (Montes Harz, Alemania) confirman el papel dominante de la zona de fractura en el flujo de agua subterránea y el transporte de solutos. Trazadores con distintos coeficientes de difusión molecular (deuterio, bromuro, uranina y eosina) dieron curvas de llegada que sólo pueden ser explicadas mediante un modelo que acople el transporte advectivo-dispersivo en las fracturas con la difusión en la matriz. Para la escala de los ensayos (distancia máxima de 225m), se usó como aproximación que la influencia de las fracturas adyacentes podía despreciarse. Este modelo dio lugar para cada trazador a valores muy similares de los parámetros de transporte, lo que supone que la aproximación de fractura única es aceptable y que la difusión en la matriz es un mecanismo importante. La conductividad hidráulica de la zona fracturada obtenida de los ensayos es de unos 1.5×10-2m/s, mientras que la conductividad hidráulica regional para la matriz rocosa es de unos 3×10-7m/s, valor estimado de la edad del tritio y la porosidad de la matriz es del 2%. Estos resultados indican que la conductividad hidráulica a lo largo de la fractura es varios órdenes de magnitud mayor que la correspondiente al resto de la parte fracturada del acuífero, lo que confirma el papel dominante de las fracturas como zonas conductoras preferentes de agua.

Flow characteristics around a deformable stenosis under pulsatile flow condition

NASA Astrophysics Data System (ADS)

Choi, Woorak; Park, Jun Hong; Byeon, Hyeokjun; Lee, Sang Joon

2018-01-01

A specific portion of a vulnerable stenosis is deformed periodically under a pulsatile blood flow condition. Detailed analysis of such deformable stenosis is important because stenotic deformation can increase the likelihood of rupture, which may lead to sudden cardiac death or stroke. Various diagnostic indices have been developed for a nondeformable stenosis by using flow characteristics and resultant pressure drop across the stenosis. However, the effects of the stenotic deformation on the flow characteristics remain poorly understood. In this study, the flows around a deformable stenosis model and two different rigid stenosis models were investigated under a pulsatile flow condition. Particle image velocimetry was employed to measure flow structures around the three stenosis models. The deformable stenosis model was deformed to achieve high geometrical slope and height when the flow rate was increased. The deformation of the stenotic shape enhanced jet deflection toward the opposite vessel wall of the stenosis. The jet deflection in the deformable model increased the rate of jet velocity and turbulent kinetic energy (TKE) production as compared with those in the rigid models. The effect of stenotic deformation on the pulsating waveform related with the pressure drop was analyzed using the TKE production rate. The deformable stenosis model exhibited a phase delay of the peak point in the waveform. These results revealed the potential use of pressure drop waveform as a diagnostic index for deformable stenosis.

The properties of Q-deformed hyperbolic and trigonometric functions in quantum deformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deta, U. A., E-mail: utamaalan@yahoo.co.id, E-mail: utamadeta@unesa.ac.id; Suparmi

2015-09-30

Quantum deformation has been studied due to its relation with applications in nuclear physics, conformal field theory, and statistical-quantum theory. The q-deformation of hyperbolic function was introduced by Arai. The application of q-deformed functions has been widely used in quantum mechanics. The properties of this two kinds of system explained in this paper including their derivative. The graph of q-deformed functions presented using Matlab. The special case is given for modified Poschl-Teller plus q-deformed Scarf II trigonometry potentials.

Aerodynamic effects of corrugation and deformation in flapping wings of hovering hoverflies.

PubMed

Du, Gang; Sun, Mao

2012-05-07

We investigated the aerodynamic effects of wing deformation and corrugation of a three-dimensional model hoverfly wing at a hovering condition by solving the Navier-Stokes equations on a dynamically deforming grid. Various corrugated wing models were tested. Insight into whether or not there existed significant aerodynamic coupling between wing deformation (camber and twist) and wing corrugation was obtained by comparing aerodynamic forces of four cases: a smooth-plate wing in flapping motion without deformation (i.e. a rigid flat-plate wing in flapping motion); a smooth-plate wing in flapping motion with deformation; a corrugated wing in flapping motion without deformation (i.e. a rigid corrugated wing in flapping motion); a corrugated wing in flapping motion with deformation. There was little aerodynamic coupling between wing deformation and corrugation: the aerodynamic effect of wing deformation and corrugation acting together was approximately a superposition of those of deformation and corrugation acting separately. When acting alone, the effect of wing deformation was to increase the lift by 9.7% and decrease the torque (or aerodynamic power) by 5.2%, and that of wing corrugation was to decrease the lift by 6.5% and increase the torque by 2.2%. But when acting together, the wing deformation and corrugation only increased the lift by ~3% and decreased the torque by ~3%. That is, the combined aerodynamic effect of deformation and corrugation is rather small. Thus, wing corrugation is mainly for structural, not aerodynamic, purpose, and in computing or measuring the aerodynamic forces, using a rigid flat-plate wing to model the corrugated deforming wing at hovering condition can be a good approximation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Localized crustal deformation in the Godavari failed rift, India

NASA Astrophysics Data System (ADS)

Mahesh, P.; Gahalaut, V. K.; Catherine, J. K.; Ambikapathy, A.; Kundu, Bhaskar; Bansal, Amit; Chadha, R. K.; Narsaiah, M.

2012-06-01

Six years of GPS measurements of crustal deformation in the Godavari failed rift (GFR) of stable India plate suggest very localized deformation. Elsewhere, all along the GFR the deformation is very low (<1.5 mm/yr). Localized deformation (up to 3.3±0.5 mm/yr) at least at two sites, implying compression on steep faults located on the southern margin of the GFR, is coincident with the region characterized by high level low-magnitude seismicity of past six years and implies strain accumulation for future moderate to strong magnitude earthquake in the region. The localized deformation is consistent with the view about deformation in such regions where seismicity migrates and deformation rate changes with time.

A homogeneous 2D deformation of geological interest: Rotation shear

NASA Astrophysics Data System (ADS)

Bastida, Fernando; Bobillo-Ares, Nilo C.; Aller, Jesús; Lisle, Richard J.

2018-07-01

We define a simple two-dimensional deformation called "rotation shear". It has one line of no finite longitudinal strain with invariant direction and another one that rotates with the deformation. An analysis of this deformation is carried out. Rotation shear superficially resembles simple shear but the analysis reveals that the two deformations have very different properties. In general, lines deformed by simple shear show a more complex deformation history and undergo greater longitudinal strain, i.e. are more extended, than lines deformed by rotation shear. Rotation shear is used to explain the development of geological structures such as kink bands, ideal similar folds, crenulation and crenulation cleavage and shear zones.

Quantitative comparison of disc rim color in optic nerve atrophy of compressive optic neuropathy and glaucomatous optic neuropathy.

PubMed

Nakano, Eri; Hata, Masayuki; Oishi, Akio; Miyamoto, Kazuaki; Uji, Akihito; Fujimoto, Masahiro; Miyata, Manabu; Yoshimura, Nagahisa

2016-08-01

The purpose was to investigate an objective and quantitative method to estimate the redness of the optic disc neuroretinal rim, and to determine the usefulness of this method to differentiate compressive optic neuropathy (CON) from glaucomatous optic neuropathy (GON). In our study there were 126 eyes: 40 with CON, 40 with normal tension glaucoma (NTG), and 46 normal eyes (NOR). Digital color fundus photographs were assessed for the redness of disc rim color using ImageJ software. We separately measured the intensity of red, green, and blue pixels from RGB images. Three disc color indices (DCIs), which indicate the redness intensity, were calculated through existing formulas. All three DCIs of CON were significantly smaller than those of NOR (P < 0.001). In addition, when compared with NTG, DCIs were also significantly smaller in CON (P < 0.05). A comparison of mild CON and mild NTG (mean deviation (MD) > -6 dB), in which the extent of retinal nerve fiber layer thinning is comparable, the DCIs of mild CON were significantly smaller than those of mild NTG (P < 0.05). In contrast, DCIs did not differ between moderate-to-severe stages of CON and NTG (MD ≤ -6 dB), though the retinal nerve fibers of CON were more severely damaged than those of NTG. To differentiate between mild CON and mild NTG, all AUROCs for the three DCIs were above 0.700. A quantitative and objective assessment of optic disc color was useful in differentiating early-stage CON from GON and NOR.

A Case Study on the Strata Movement Mechanism and Surface Deformation Regulation in Chengchao Underground Iron Mine

NASA Astrophysics Data System (ADS)

Cheng, Guanwen; Chen, Congxin; Ma, Tianhui; Liu, Hongyuan; Tang, Chunan

2017-04-01

The regular pattern of surface deformation and the mechanism of underground strata movement, especially in iron mines constructed with the block caving method, have a great influence on infrastructure on the surface, so they are an important topic for research. Based on the engineering geology conditions and the surface deformation and fracture features in Chengchao Iron Mine, the mechanism of strata movement and the regular pattern of surface deformation in the footwall were studied by the geomechanical method, and the following conclusions can be drawn: I. The surface deformation process is divided into two stages over time, i.e., the chimney caving development stage and the post-chimney deformation stage. Currently, the surface deformation in Chengchao Iron Mine is at the post-chimney deformation stage. II. At the post-chimney deformation stage, the surface deformation and geological hazards in Chengchao Iron Mine are primarily controlled by the NWW-trending joints, with the phenomenon of toppling deformation and failure on the surface. Based on the surface deformation characteristics in Chengchao Iron Mine, the surface deformation area can be divided into the following four zones: the fracture extension zone, the fracture closure zone, the fracture formation zone and the deformation accumulation zone. The zones on the surface can be determined by the surface deformation characteristics. III. The cantilever beams near the chimney caving area, caused by the NWW-trending joints, have been subjected to toppling failure. This causes the different deformation and failure mechanisms in different locations of the deep rock mass. The deep rock can be divided into four zones, i.e., the fracture zone, fracture transition zone, deformation zone and undisturbed zone, according to the different deformation and failure mechanisms. The zones in the deep rock are the reason for the zones on the surface, so they can be determined by the zones on the surface. Through these findings, the degree of damage to the infrastructure in different locations can be determined based on the surface deformation zones. As the mining continues deeper, the development regulation of the zones on the surface and in deep rock mass can be further studied based on the zones in the deep rock.

Exploring of PST-TBPM in Monitoring Dynamic Deformation of Steel Structure in Vibration

NASA Astrophysics Data System (ADS)

Chen, Mingzhi; Zhao, Yongqian; Hai, Hua; Yu, Chengxin; Zhang, Guojian

2018-01-01

In order to monitor the dynamic deformation of steel structure in the real-time, digital photography is used in this paper. Firstly, the grid method is used correct the distortion of digital camera. Then the digital cameras are used to capture the initial and experimental images of steel structure to obtain its relative deformation. PST-TBPM (photographing scale transformation-time baseline parallax method) is used to eliminate the parallax error and convert the pixel change value of deformation points into the actual displacement value. In order to visualize the deformation trend of steel structure, the deformation curves are drawn based on the deformation value of deformation points. Results show that the average absolute accuracy and relative accuracy of PST-TBPM are 0.28mm and 1.1‰, respectively. Digital photography used in this study can meet accuracy requirements of steel structure deformation monitoring. It also can warn the safety of steel structure and provide data support for managers’ safety decisions based on the deformation curves on site.

Advantages of formulating an evolution equation directly for elastic distortional deformation in finite deformation plasticity

NASA Astrophysics Data System (ADS)

Rubin, M. B.; Cardiff, P.

2017-11-01

Simo (Comput Methods Appl Mech Eng 66:199-219, 1988) proposed an evolution equation for elastic deformation together with a constitutive equation for inelastic deformation rate in plasticity. The numerical algorithm (Simo in Comput Methods Appl Mech Eng 68:1-31, 1988) for determining elastic distortional deformation was simple. However, the proposed inelastic deformation rate caused plastic compaction. The corrected formulation (Simo in Comput Methods Appl Mech Eng 99:61-112, 1992) preserves isochoric plasticity but the numerical integration algorithm is complicated and needs special methods for calculation of the exponential map of a tensor. Alternatively, an evolution equation for elastic distortional deformation can be proposed directly with a simplified constitutive equation for inelastic distortional deformation rate. This has the advantage that the physics of inelastic distortional deformation is separated from that of dilatation. The example of finite deformation J2 plasticity with linear isotropic hardening is used to demonstrate the simplicity of the numerical algorithm.

40 CFR 180.1213 - Coniothyrium minitans strain CON/M/91-08; exemption from the requirement of a tolerance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Coniothyrium minitans strain CON/M/91... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1213 Coniothyrium minitans strain CON/M... tolerance is established for residues of the microbial pesticide Coniothyrium minitans strain CON/M/91-08...

40 CFR 180.1213 - Coniothyrium minitans strain CON/M/91-08; exemption from the requirement of a tolerance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Coniothyrium minitans strain CON/M/91... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1213 Coniothyrium minitans strain CON/M... tolerance is established for residues of the microbial pesticide Coniothyrium minitans strain CON/M/91-08...

Models of determining deformations

NASA Astrophysics Data System (ADS)

Gladilin, V. N.

2016-12-01

In recent years, a lot of functions designed to determine deformation values that occur mostly as a result of settlement of structures and industrial equipment. Some authors suggest such advanced mathematical functions approximating deformations as general methods for the determination of deformations. The article describes models of deformations as physical processes. When comparing static, cinematic and dynamic models, it was found that the dynamic model reflects the deformation of structures and industrial equipment most reliably.

Characterisation of the hydrogeology of the Augustus River catchment, Western Australia

NASA Astrophysics Data System (ADS)

Wilkes, Shane M.; Clement, T. Prabhakar; Otto, Claus J.

Understanding the hydrogeology of weathered rock catchments is integral for the management of various problems related to increased salinity within the many towns of Western Australia. This paper presents the results of site characterisation investigations aimed at improving the overall understanding of the hydrogeology of the southern portion of the Augustus River catchment, an example of a weathered rock catchment. Site data have highlighted the presence of both porous media aquifers within the weathered profile and fractured rock aquifers within the basement rocks. Geophysical airborne surveys and other drilling data have identified a large number of dolerite dykes which crosscut the site. Fractured quartz veins have been found along the margins of these dolerite dykes. Detailed groundwater-level measurements and barometric efficiency estimates indicate that these dolerite dykes and fractured quartz veins are affecting groundwater flow directions, promoting a strong hydraulic connection between all aquifers, and also influencing recharge mechanisms. The hydrogeological significance of the dolerite dykes and fractured quartz veins has been assessed using a combination of high-frequency groundwater-level measurements (30-min sampling interval), rainfall measurements (5-min sampling interval) and barometric pressure fluctuations (30-min sampling interval). A conceptual model was developed for describing various hydrogeological features of the study area. The model indicates that fractured quartz veins along the margins of dolerite dykes are an important component of the hydrogeology of the weathered rock catchments. Comprendre l'hydrogéologie des bassins en roches altérées est essentiel pour la gestion de différents problèmes liés à l'augmentation de la salinité dans de nombreuses villes d'Australie occidentale. Cet article présente les résultats d'études de caractérisation de sites conduites pour améliorer la compréhension de l'hydrogéologie de la partie sud du bassin de la rivière Augustus, exemple de bassin en roches altérées. Les données concernant le site ont mis en évidence la présence simultanée d'aquifères poreux dans le profil d'altération et d'aquifères de roches fracturées dans le socle. Des campagnes de géophysique aéroportée et d'autres données de forages ont identifié de très nombreux dykes de dolérite traversant le site. Des veines de quartz fracturées ont été trouvées aux marges de ces dykes de dolérite. Des mesures détaillées de niveau des nappes et des estimations des effets barométriques indiquent que ces dykes de dolérite et les veines de quartz fracturées affectent les directions d'écoulement souterrain, favorisant une forte connexion hydraulique entre tous ces aquifères, et influençant également les mécanismes de recharge. La signification hydrogéologique des dykes de dolérite et des veines de quartz fracturées a été analysée en combinant des mesures à haute fréquence du niveau des nappes (toutes les 30 min), de la pluie (toutes les 5 min) et des variations de la pression barométrique (toutes les 30 min). Un modèle conceptuel a été établi pour décrire les différents phénomènes hydrogéologiques de la région étudiée. Ce modèle indique que les veines de quartz aux marges des dykes de dolérite sont une importante composante de l'hydrogéologie des bassins en roches altérées. Entender la hidrogeología de cuencas con rocas meteorizadas es esencial para gestionar diversos problemas relacionados con el incremento de salinidad en muchas ciudades de Australia Occidental. Este artículo presenta los resultados obtenidos en la caracterización de varios emplazamientos con el fin de mejorar el conocimiento general de la hidrogeología en la zona sur de la cuenca del Río Augustus, que sirve como ejemplo de cuenca en rocas meteorizadas. Los datos de campo resaltan la presencia tanto de medios acuíferos porosos dentro del perfil meteorizado como de acuíferos en rocas fracturadas dentro de la roca fresca. Los registros geofísicos aéreos y datos de las perforaciones han identificado un gran número de diques de dolerita que intersectan el emplazamiento. Se ha hallado venas de cuarzo fracturado a lo largo de los márgenes de los diques de dolerita. Medidas detalladas del nivel piezométrico y estimaciones de la eficiencia barométrica indican que los diques de dolerita y las venas de cuarzo fracturado afectan las direcciones del flujo de las aguas subterráneas, originando una fuerte conexión hidráulica entre todos los acuíferos e influenciando también a los mecanismos de recarga. Se ha establecido la importancia hidrogeológica de los diques de dolerita y de las venas de cuarzo fracturado mediante una combinación de medidas muy frecuentes del nivel piezométrico (cada 30 min), de la precipitación (cada 5 min) y de las fluctuaciones de la presión barométrica (cada 30 min). Se ha desarrollado un modelo conceptual para describir varias características hidrogeológicas del área de estudio. El modelo indica que las venas de cuarzo fracturado en los márgenes de los diques de dolerita constituyen un componente importante de la hidrogeología de cuencas con rocas meteorizadas.

The Role of Wrench Tectonics In The Neogene-quaternary Evolution of The Western Hyblean Plateau (sicily)

NASA Astrophysics Data System (ADS)

Mattina, D.

This study focussed on the kinematics and temporal variations of neotectonic-to-active structures on the margin of the Southern Apennines thrust front. The border between the thrustbelt contractional terranes and continental plateau hosts a number of strike- slip and, secondarily, normal structures of still disputed geometry. Based on newly- acquired data, this research opened new issues with respect to present-day kinematics of these fault systems, suggesting a new interpretation for the tectonic mechanisms underpinning the Hyblean plateau. Given its geodynamic environs, the present-day structural configuration of this plateau reflects a long tectonic history involving both intraplate extension and plate margin deformation. As a consequence, the platform area has been dominated by a complex interplay between extensional, compressional and strike-slip tectonics, expressed by subvertical faults that can be brokendown into two main trends: NE-SW and NNE- SSW. Fieldwork, integrated by interpretation of aerial photos and SPOT images, con- tributed to constrain and enhance a structural model of the region. The main NNE- SSW fault system (Scicli - Ragusa - Giarratana) is well exposed in the western part of the Hyblean plateau, called Ragusa Platform. This is an important structural feature which affects all domains present here and is characterised by vertical slip rates with a lateral component of motion. Structural analysis was primarily concentrated in this zone. Notably, a large set of structural elements, associated with a principal rigth-lateral NNE-SSW and NE-SW fault zone, was documented in the area and local transpressive elements, associated with these faults, are shown on the basis of their morphological evidence. A large bending and elevated area characterises the northern edge of the Ragusa platform and unveils the presence of several N-S striking reverse faults, with dextral lateral component of movement, and anticlinal folds. The detailed meso-structural analysis conducted on the Ragusa platform revealed the presence of non-coaxial compressive deformations, which in turn generated folds, re- verse faults and rare thrusts, involving the Upper Miocene - Lower Pleistocene de- posits. The structural analysis was conducted at the 1:25.000 scale, using the dis- persion of bedding data to define the orientation of the main structures. These data display a certain scattering but nevertheless allow to recognise a common trend; the 1 main fold system is characterised by structures trending~N-S. Subordinately, another set of folds is present; these are less developed and continuous than the previous sys- tem, forming fold with an average trend of about N 140E. The scattering of these structures is summarized in the structural model developed, including diagrams of some meso-folds recognized in the field. The presence of reverse faults is interpreted as flower structures and push-up systems which developed in a transpressive stress regime. In order to devise a tectonic model of the Hyblean plateau, the structural dataset was supplemented with a comparative morphological analysis, as revealed by fieldwork, satellite images, aerial photos and topographic data. Drainage network has been thor- oughly ascertained. In the case that the preferential directions of rivers were statisti- cally significant and different from those expected from non-structural controls (e.g. topographic and geographic trend), they were deemed to be a diagnostic tool to iden- tify the deformation system. This is based on the assumption of a strict structural control on the local hydrographic network and its evolution. The close relationship between the structural and morphological features underline the recent activity of the main fault trends. This study indicates that widespread occurrence of folds and reverse faulting can be ascribed to the transpressive regime, as a consequence of regional active wrenching capable of generating push-up and positive flower structures. Consequently, transform systems and brittle/ductile deformation is herewith envisaged to pertain to a single ma- jor deformation event. Within the central Mediterranean framework, the Scicli shear zone represents the on-shore strand of a major dextral transform system, documented off-shore to be the triggering mechanism responsible for the opening of the Sicily Strait. Such system also splits the western and eastern sectors of the Hyblean plateau, as indicated by differing kinematic evolutions. Present-day opening of the Pantelleria Rift, connected to a NE-SW extensional axis (Illies etl., 1981; Finetti et al., 1982; Boccaletti et al., 1987), activated the NNE trans- form system, whose on-shore expressions are highlighted by Scicli and Chiaramonte structures. Inception of activity for these fault systems is synchronous with the one characterizing the Rift (5 Ma; Ben-Avraham et al., 1991). Such line of evidence would enable to substantiate the Plio-Pleistocene shear mechanisms documented along these faults, indicating its viability within a regional stress field. Its likely s1, triggering con- traction at the plate boundary and causative of the rifting transtensional regime, would therefore be oriented NW-SE. 2

Plains Tectonics on Venus

NASA Technical Reports Server (NTRS)

Banerdt, W. B.; McGill, G. E.; Zuber, M. T.

1996-01-01

Tectonic deformation in the plains of Venus is pervasive, with virtually every area of the planet showing evidence for faulting or fracturing. This deformation can be classified into three general categories, defined by the intensity and areal extent of the surface deformation: distributed deformation, concentrated deformation, and local fracture patterns.

Jordanian deformation of SL(2) as a contraction of its Drinfeld-Jimbo deformation

NASA Astrophysics Data System (ADS)

Aghamohammadi, A.; Khorrami, M.; Shariati, A.

1995-04-01

We show that $h$-deformation can be obtained, by a singular limit of a similarity transformation, from $q$-deformation; to be specefic, we obtain $\\GL_h(2)$, its differential structure, its inhomogenous extension, and $\\Uh{\\sl(2)}$ from their $q$-deformed counterparts.

Effects of abrupt introduction and removal of high and low digestibility corn distillers dried grains with solubles from the diet on growth performance and carcass characteristics of growing-finishing pigs.

PubMed

Hilbrands, A M; Johnston, L J; McClelland, K M; Cox, R B; Baidoo, S K; Souza, L W O; Shurson, G C

2013-01-01

Two experiments were conducted to evaluate the effects of feeding continuously a diet containing 40% dried distillers grains with solubles (DDGS) or intermittently diets containing 20 or 40% DDGS on growth performance and carcass quality of pigs. Responses of the pigs to abrupt introduction and removal of dietary DDGS with differing concentrations of standardized ileal digestible (SID) AA were also evaluated. In Exp. 1, crossbred pigs (n=216; initial BW=51.3±3.1 kg) were assigned randomly to 1 of 4 treatments, which included a corn-soybean meal control (CON), a 20% DDGS diet (D20), a switch between D20 and CON (D20-CON), and a switch between a 40% DDGS diet and CON (D40-CON) with 6 pens per treatment. Pigs abruptly introduced and removed from a 20% DDGS diet (D20-CON) exhibited no differences in growth performance or carcass quality compared with CON pigs. However, intermittently feeding a 40% DDGS diet (D40-CON) resulted in lighter HCW (P<0.05) compared with all other treatments. In Exp. 2, crossbred pigs (n=324; initial BW=33.2±3.0 kg) were assigned randomly to 1 of 6 treatments, including a corn-soybean meal control (CON), a 40% low SID AA DDGS diet (LD), a 40% high SID AA DDGS diet (HD), LD and CON diets alternated (LD-CON), HD and CON diets alternated (HD-CON), or HD and LD diets alternated (HD-LD) with 6 pens per treatment. Final BW and ADG were less (P<0.05) for LD and HD-LD pigs compared with CON pigs, but HD pigs tended to have reduced (P<0.10) final BW and ADG. Loin muscle area was smaller for LD and HD-LD pigs compared with CON pigs (P<0.05). Percentage carcass lean was not affected by dietary treatment. Backfat of DDGS-fed pigs was more unsaturated than CON pigs, but AA digestibility of DDGS did not affect this response. Digestibility of AA in DDGS can influence pig performance and carcass quality when fed at high concentrations (40% or more). The use of a high SID AA DDGS source may diminish some of the negative responses observed for growth performance and carcass characteristics when feeding high concentrations of DDGS if accurate values of SID AA are used in diet formulation. Periodic inclusion and removal of 40% DDGS from diets did not adversely affect growth performance or carcass quality regardless of the SID AA digestibility of the DDGS used. These results indicate that it is possible to abruptly incorporate and remove DDGS from grower-finisher swine diets without meaningful detrimental effects on growth performance or carcass quality.

Patterns of Alloy Deformation by Pulsed Pressure

NASA Astrophysics Data System (ADS)

Chebotnyagin, L. M.; Potapov, V. V.; Lopatin, V. V.

2015-06-01

Patterns of alloy deformation for optimization of a welding regime are studied by the method of modeling and deformation profiles providing high deformation quality are determined. A model of stepwise kinetics of the alloy deformation by pulsed pressure from the expanding plasma channel inside of a deformable cylinder is suggested. The model is based on the analogy between the acoustic and electromagnetic wave processes in long lines. The shock wave pattern of alloy deformation in the presence of multiple reflections of pulsed pressure waves in the gap plasma channel - cylinder wall and the influence of unloading waves from free surfaces are confirmed.

Identification of Skeletal Deformities in Far Eastern Catfish, Silurus asotus under Indoor Aquaculture Condition

PubMed Central

Yang, Won Seok; Gil, Hyun Woo; Yoo, Gwang Yeol; Park, In-Seok

2015-01-01

For the 2 years of farming, at the indoor circulating aquaculture system, four kinds of skeletal deformities were found among 60 Far Eastern catfish, Silurus asotus. Deformities saw jawbone’s luxation, abnormality of upper lip and malocclusion. Spinal deformity was most fatal deformities with low weight and small length. Jawbone’s luxation had 1 maxilla and 2 mandibles. Abnormality of upper lip had just lip was back over. Malocclusion’s left maxilla and right maxilla were not balanced. This experiment was any deformities in this species through the deformity can grasp how it affects. PMID:27004272

Treating the Proximal Interphalangeal Joint in Swan Neck and Boutonniere Deformities.

PubMed

Fox, Paige M; Chang, James

2018-05-01

Swan neck and boutonniere deformities of the proximal interphalangeal (PIP) joint are challenging to treat. In a swan neck deformity, the PIP joint is hyperextended with flexion at the distal interphalangeal (DIP) joint. In a boutonniere deformity, there is flexion the PIP joint with hyperextension of the DIP joint. When the deformities are flexible, treatment begins with splinting. However, when the deformity is fixed, serial casting or surgery is often necessary to restore joint motion before surgical correction. Many surgical techniques have been described to treat both conditions. Unfortunately, incomplete correction and deformity recurrence are common. Published by Elsevier Inc.

Management of Congenital Chest Wall Deformities

PubMed Central

Blanco, Felix C.; Elliott, Steven T.; Sandler, Anthony D.

2011-01-01

Congenital chest wall deformities are considered to be anomalies in chest wall growth. These can be categorized as either rib cage overgrowth or deformities related to inadequate growth (aplasia or dysplasia). Rib cage overgrowth leads to depression of the sternum (pectus excavatum) or protuberance of the sternum (pectus carinatum) and accounts for greater than 90% of congenital chest wall deformities. The remaining deformities are a result of inadequate growth. Evolution in the management of congenital chest wall deformities has made significant progress over the past 25 years. This article will review chest wall deformities and the current management strategies of these interesting anomalies. PMID:22294949

Simulation of high-temperature superlocalization of plastic deformation in single-crystals of alloys with an L12 superstructure

NASA Astrophysics Data System (ADS)

Solov'eva, Yu. V.; Fakhrutdinova, Ya. D.; Starenchenko, V. A.

2015-01-01

The processes of the superlocalization of plastic deformation in L12 alloys have been studied numerically based on a combination of the model of the dislocation kinetics of the deformation-induced and heat-treatment-induced strengthening of an element of a deformable medium with the model of the mechanics of microplastic deformation described in terms of elastoplastic medium. It has been shown that the superlocalization of plastic deformation is determined by the presence of stress concentrators and by the nonmonotonic strengthening of the elements of the deformable medium. The multiple nonmonotonicity of the process of strengthening of the elementary volume of the medium can be responsible for the multiplicity of bands of microplastic localization of deformation.

Mechanical Failure Mode of Metal Nanowires: Global Deformation versus Local Deformation

PubMed Central

Ho, Duc Tam; Im, Youngtae; Kwon, Soon-Yong; Earmme, Youn Young; Kim, Sung Youb

2015-01-01

It is believed that the failure mode of metal nanowires under tensile loading is the result of the nucleation and propagation of dislocations. Such failure modes can be slip, partial slip or twinning and therefore they are regarded as local deformation. Here we provide numerical and theoretical evidences to show that global deformation is another predominant failure mode of nanowires under tensile loading. At the global deformation mode, nanowires fail with a large contraction along a lateral direction and a large expansion along the other lateral direction. In addition, there is a competition between global and local deformations. Nanowires loaded at low temperature exhibit global failure mode first and then local deformation follows later. We show that the global deformation originates from the intrinsic instability of the nanowires and that temperature is a main parameter that decides the global or local deformation as the failure mode of nanowires. PMID:26087445

Influence of thermally activated processes on the deformation behavior during low temperature ECAP

NASA Astrophysics Data System (ADS)

Fritsch, S.; Scholze, M.; F-X Wagner, M.

2016-03-01

High strength aluminum alloys are generally hard to deform. Therefore, the application of conventional severe plastic deformation methods to generate ultrafine-grained microstructures and to further increase strength is considerably limited. In this study, we consider low temperature deformation in a custom-built, cooled equal channel angular pressing (ECAP) tool (internal angle 90°) as an alternative approach to severely plastically deform a 7075 aluminum alloy. To document the maximum improvement of mechanical properties, these alloys are initially deformed from a solid solution heat-treated condition. We characterize the mechanical behavior and the microstructure of the coarse grained initial material at different low temperatures, and we analyze how a tendency for the PLC effect and the strain-hardening rate affect the formability during subsequent severe plastic deformation at low temperatures. We then discuss how the deformation temperature and velocity influence the occurrence of PLC effects and the homogeneity of the deformed ECAP billets. Besides the mechanical properties and these microstructural changes, we discuss technologically relevant processing parameters (such as pressing forces) and practical limitations, as well as changes in fracture behavior of the low temperature deformed materials as a function of deformation temperature.

Evaluation of mechanical deformation and distributive magnetic loads with different mechanical constraints in two parallel conducting bars

NASA Astrophysics Data System (ADS)

Lee, Ho-Young; Lee, Se-Hee

2017-08-01

Mechanical deformation, bending deformation, and distributive magnetic loads were evaluated numerically and experimentally for conducting materials excited with high current. Until now, many research works have extensively studied the area of magnetic force and mechanical deformation by using coupled approaches such as multiphysics solvers. In coupled analysis for magnetoelastic problems, some articles and commercial software have presented the resultant mechanical deformation and stress on the body. To evaluate the mechanical deformation, the Lorentz force density method (LZ) and the Maxwell stress tensor method (MX) have been widely used for conducting materials. However, it is difficult to find any experimental verification regarding mechanical deformation or bending deformation due to magnetic force density. Therefore, we compared our numerical results to those from experiments with two parallel conducting bars to verify our numerical setup for bending deformation. Before showing this, the basic and interesting coupled simulation was conducted to test the mechanical deformations by the LZ (body force density) and the MX (surface force density) methods. This resulted in MX gave the same total force as LZ, but the local force distribution in MX introduced an incorrect mechanical deformation in the simulation of a solid conductor.

Fluid flow in deforming media: interpreting stable isotope signatures of marbles

NASA Astrophysics Data System (ADS)

Bond, C. E.

2016-12-01

Fluid flow in the crust is controlled by permeable networks. These networks can be created and destroyed dynamically during rock deformation. Rock deformation is therefore critical in controlling fluid pathways in the crust and hence the location of mineral and other resources. Here, evidence for deformation-enhanced fluid infiltration shows that a range of deformation mechanisms control fluid flow and chemical and isotopic equilibration. The results attest to localised fluid infiltration within a single metamorphic terrain (12km) over a range of metamorphic grades; ecologite- blueschist to greenschist. For fluid infiltrating marbles during ductile deformation, chemical and isotopic signatures are now homogenous; whilst fluid infiltration associated with brittle deformation results in chemical and isotopic heterogeneity at a microscale. The findings demonstrate how ductile deformation enhances equilibration of δ18O at a grain scale whilst brittle deformation does not. The control of deformation mechanisms in equilibrating isotopic and chemical heterogeneities have implications for the understanding of fluid-rock interaction in the crust. Interpretation of bulk stable isotope data, particularly in the use of isotope profiles to determine fluid fluxes into relatively impermeable units that have been deformed need to be used with care when trying to determine fluid fluxes and infiltration mechanisms.

Comparação de modelos para o cálculo de perturbações orbitais devidas à maré terrestre

NASA Astrophysics Data System (ADS)

Vieira Pinto, J.; Vilhena de Moraes, R.

2003-08-01

Aplicações recentes de satélites artificiais com finalidades geodinâmicas requerem órbitas determinadas com bastante precisão. Em particular marés terrestres influenciam o potencial terrestre causando perturbações adicionais no movimento de satélites artificiais, as quais tem sido medidas por diversos processos. A atração exercida pela lua e pelo sol sobre a terra produz deslocamentos elásticos em seu interior e uma protuberância em sua superfície. O resultado é uma pequena variação na distribuição da massa na terra, consequentemente no geopotencial. As perturbações nos elementos orbitais de satélites artificiais terrestres devidas a maré terrestre podem ser estudadas a partir das equações de Lagrange, considerando-se um conveniente potencial. Por outro lado, como tem sido feito pelo IERS, as mudanças induzidas pela maré terrestre no geopotencial podem ser convenientemente modeladas como variações nos coeficientes Cnm e Snm do geopotencial. As duas teorias ainda não foram comparados para um mesmo satélite. Neste trabalho são apresentadas e comparadas as variações de longo período e seculares nas perturbações orbitais devidas à maré terrestre, calculadas por um modelo simples, o de Kozai, e pelo modelo do IERS. Resultados preliminares mostram, para os satélites SCD2 e CBERS1, e para a Lua em movimento elíptico e precessionando, as perturbações seculares no argumento do perigeu e na longitude do nodo ascendente.

Pros and Cons of International Weapons Procurement Collaboration.

DTIC Science & Technology

1995-01-01

ad- vanced U.S. industry. Greater risk of cost growth and schedule slippage. Pro: U.S. and partners share common equip- ment. Con : U.S. require...Mark A., 1947- Pros and cons of international weapons procurement collaboration / Mark Lorell, Julia Lowell, p. cm "Prepared for the Office...one/ Cons of International Weapons Procurement Collaboration Mark Lorell Julia Lowell National Defense Research Institute Prepared for the

Quantitative (31)P NMR spectroscopy and (1)H MRI measurements of bone mineral and matrix density differentiate metabolic bone diseases in rat models.

PubMed

Cao, Haihui; Nazarian, Ara; Ackerman, Jerome L; Snyder, Brian D; Rosenberg, Andrew E; Nazarian, Rosalynn M; Hrovat, Mirko I; Dai, Guangping; Mintzopoulos, Dionyssios; Wu, Yaotang

2010-06-01

In this study, bone mineral density (BMD) of normal (CON), ovariectomized (OVX), and partially nephrectomized (NFR) rats was measured by (31)P NMR spectroscopy; bone matrix density was measured by (1)H water- and fat-suppressed projection imaging (WASPI); and the extent of bone mineralization (EBM) was obtained by the ratio of BMD/bone matrix density. The capability of these MR methods to distinguish the bone composition of the CON, OVX, and NFR groups was evaluated against chemical analysis (gravimetry). For cortical bone specimens, BMD of the CON and OVX groups was not significantly different; BMD of the NFR group was 22.1% (by (31)P NMR) and 17.5% (by gravimetry) lower than CON. For trabecular bone specimens, BMD of the OVX group was 40.5% (by (31)P NMR) and 24.6% (by gravimetry) lower than CON; BMD of the NFR group was 26.8% (by (31)P NMR) and 21.5% (by gravimetry) lower than CON. No significant change of cortical bone matrix density between CON and OVX was observed by WASPI or gravimetry; NFR cortical bone matrix density was 10.3% (by WASPI) and 13.9% (by gravimetry) lower than CON. OVX trabecular bone matrix density was 38.0% (by WASPI) and 30.8% (by gravimetry) lower than CON, while no significant change in NFR trabecular bone matrix density was observed by either method. The EBMs of OVX cortical and trabecular specimens were slightly higher than CON but not significantly different from CON. Importantly, EBMs of NFR cortical and trabecular specimens were 12.4% and 26.3% lower than CON by (31)P NMR/WASPI, respectively, and 4.0% and 11.9% lower by gravimetry. Histopathology showed evidence of osteoporosis in the OVX group and severe secondary hyperparathyroidism (renal osteodystrophy) in the NFR group. These results demonstrate that the combined (31)P NMR/WASPI method is capable of discerning the difference in EBM between animals with osteoporosis and those with impaired bone mineralization. Copyright 2010 Elsevier Inc. All rights reserved.

Frequent nasopharyngeal suctioning as a risk factor associated with neonatal coagulase-negative staphylococcal colonisation and sepsis

PubMed Central

Boo, Nem Yun; Suhaida, Abdul Rahman; Rohana, Jaafar

2015-01-01

INTRODUCTION This case-control study aimed to determine whether catheter use was significantly associated with coagulase-negative staphylococci (CoNS) colonisation and/or sepsis in neonates. METHODS Weekly swabs of the nose, umbilicus, rectum, wounds, eye discharge and intravenous catheter tips (after removal) of infants admitted to the neonatal intensive care unit of Universiti Kebangsaan Malaysia Medical Centre, Malaysia, were cultured. CoNS sepsis was diagnosed if pure growth of CoNS was cultured from the peripheral blood specimen of symptomatic infants. For each infant with CoNS colonisation or sepsis, a control infant was retrospectively and randomly selected from unaffected infants in the ward. Multivariate analyses were performed to determine whether catheter use was a significant risk factor. RESULTS CoNS colonisation was detected in 113 (8.7%) infants. CoNS sepsis was found in 12 (10.6%) infants with CoNS colonisation and 7 (0.6%) infants without CoNS colonisation. Multivariate analysis showed that the following were significantly associated with CoNS colonisation: conjunctivitis (adjusted odds ratio [OR] 8.2, 95% confidence interval [CI] 1.9–34.8, p = 0.005); central venous catheters (adjusted OR 5.8, 95% CI 1.9–17.8, p = 0.002); and nasopharyngeal and/or oral suctioning more than twice in the 48 hours before positive culture (adjusted OR 7.3, 95% CI 3.3–16.2, p < 0.001). Exposure to frequent nasopharyngeal and/or oral suctioning (adjusted OR 20.8, 95% CI 3.5–125.3, p = 0.001) was the only significant factor associated with CoNS sepsis. CONCLUSION Infants requiring more than two nasopharyngeal and/or oral suctions in the previous 48 hours were found to have a higher risk of developing CoNS colonisation and sepsis. PMID:25532513

Evaluation of various deformable image registrations for point and volume variations

NASA Astrophysics Data System (ADS)

Han, Su Chul; Lee, Soon Sung; Kim, Mi-Sook; Ji, Young Hoon; Kim, Kum Bae; Choi, Sang Hyun; Park, Seungwoo; Jung, Haijo; Yoo, Hyung Jun; Yi, Chul Young

2015-07-01

The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiationtreatment planning. Many groups have studied the accuracy of DIR. In this study, we evaluatedthe accuracy of various DIR algorithms by using variations of the deformation point and volume.The reference image (I ref ) and volume (V ref ) were first generated by using virtual deformation QAsoftware (ImSimQA, Oncology System Limited, UK). We deformed I ref with axial movement of thedeformation point and V ref , depending on the type of deformation (relaxation and contraction) inImSimQA software. The deformed image (I def ) and volume (V def ) acquired by using the ImSimQAsoftware were inversely deformed relative to I ref and V ref by using DIR algorithms. As a result,we acquired a deformed image (I id ) from I def and volume (V id ) from V ref . Four intensity-basedalgorithms were tested by following the horn-schunk optical flow (HS), iterative optical flow (IOF),modified demons (MD) and fast demons (FD) with the Deformable Image Registration and AdaptiveRadiotherapy Toolkit (DIRART) of MATLAB. The image similarity between I ref and I id wascalculated to evaluate the accuracy of DIR algorithms using by Normalized Mutual Information(NMI) and Normalized Cross Correlation (NCC) metrics, when the distance of point deformationwas moved 4 mm, the value of NMI was above 1.81 and that of NCC was above 0.99 in all DIRalgorithms. As the degree of deformation was increased, the degree of image similarity decreased.When the V ref was increased or decreased by about 12%, the difference between V ref and V id waswithin ±5% regardless of the type of deformation, the deformation was classified into two types:deformation 1 increased the V ref (relaxation) and deformation 2 decreased the V ref (contraction).The value of the Dice Similarity Coefficient (DSC) was above 0.95 in deformation 1 except for theMD algorithm. In the case of deformation 2, the value of the DSC was above 0.95 in all DIR algorithms.The I def and the V def were not completely restored to I ref and V ref , and the accuracy ofthe DIR algorithms were different, depending on the degree of deformation. Hence, the performanceof DIR algorithms should be verified for the desired applications

Role of insulin on exercise-induced GLUT-4 protein expression and glycogen supercompensation in rat skeletal muscle.

PubMed

Kuo, Chia-Hua; Hwang, Hyonson; Lee, Man-Cheong; Castle, Arthur L; Ivy, John L

2004-02-01

The purpose of this study was to investigate the role of insulin on skeletal muscle GLUT-4 protein expression and glycogen storage after postexercise carbohydrate supplementation. Male Sprague-Dawley rats were randomly assigned to one of six treatment groups: sedentary control (Con), Con with streptozocin (Stz/C), immediately postexercise (Ex0), Ex0 with Stz (Stz/Ex0), 5-h postexercise (Ex5), and Ex5 with Stz (Stz/Ex5). Rats were exercised by swimming (2 bouts of 3 h) and carbohydrate supplemented immediately after each exercise session by glucose intubation (1 ml of a 50% wt/vol). Stz was administered 72-h before exercise, which resulted in hyperglycemia and elimination of the insulin response to the carbohydrate supplement. GLUT-4 protein of Ex0 rats was 30% above Con in fast-twitch (FT) red and 21% above Con in FT white muscle. In Ex5, GLUT-4 protein was 52% above Con in FT red and 47% above Con in FT white muscle. Muscle glycogen in FT red and white muscle was also increased above Con in Ex5 rats. Neither GLUT-4 protein nor muscle glycogen was increased above Con in Stz/Ex0 or Stz/Ex5 rats. GLUT-4 mRNA in FT red muscle of Ex0 rats was 61% above Con but only 33% above Con in Ex5 rats. GLUT-4 mRNA in FT red muscle of Stz/C and Stz/Ex0 rats was similar but significantly elevated in Ex5/Stz rats. These results suggest that insulin is essential for the increase in GLUT-4 protein expression following postexercise carbohydrate supplementation.

A Randomized Phase 2 Study of Long-Acting TransCon GH vs Daily GH in Childhood GH Deficiency.

PubMed

Chatelain, Pierre; Malievskiy, Oleg; Radziuk, Klaudziya; Senatorova, Ganna; Abdou, Magdy O; Vlachopapadopoulou, Elpis; Skorodok, Yulia; Peterkova, Valentina; Leff, Jonathan A; Beckert, Michael

2017-05-01

TransCon Growth Hormone (GH) (Ascendis Pharma) is a long-acting recombinant sustained-release human GH prodrug in development for children with GH deficiency (GHD). To compare the pharmacokinetics, pharmacodynamics, safety, and efficacy of weekly TransCon GH to that of daily GH in prepubertal children with GHD. Randomized, open-label, active-controlled study of three doses of weekly TransCon GH versus daily Genotropin (Pfizer). Thirty-eight centers in 14 European countries and Egypt. Prepubertal male and female treatment-naïve children with GHD (n = 53). Subjects received one of three TransCon GH doses (0.14, 0.21, or 0.30 mg GH/kg/wk) or Genotropin 0.03 mg GH/kg/d for 26 weeks. GH and insulinlike growth factor-1 (IGF-1) levels, growth, adverse events, and immunogenicity. Both GH maximum concentration and area under the curve were similar following TransCon GH or Genotropin administration at comparable doses. A dose response was observed, with IGF-1 standard deviation scores increasing into the normal range for all three TransCon GH doses. Annualized mean height velocity for the three TransCon GH doses ranged from 11.9 cm to 13.9 cm, which was not statistically different from 11.6 cm for Genotropin. Adverse events were mild to moderate, and most were unrelated to the study drug. Injection site tolerance was good. One TransCon GH subject developed a low-titer, nonneutralizing antibody response to GH. The results suggest that long-acting TransCon GH is comparable to daily Genotropin for GH (pharmacokinetics) and IGF-1 (pharmacodynamics) levels, safety, and efficacy and support advancement into phase 3 development. Copyright © 2017 Endocrine Society

Immunocontraception for Managing Feral Cattle in Hong Kong

PubMed Central

Massei, Giovanna; Koon, Ka-Kei; Benton, Steven; Brown, Richard; Gomm, Matt; Orahood, Darcy S.; Pietravalle, Stéphane; Eckery, Douglas C.

2015-01-01

Conflicts between human interests and feral cattle in Hong Kong derive from growing numbers of free-roaming cattle. Public antipathy towards lethal population control led the local authorities to consider fertility control to reduce cattle numbers. This study assessed the potential side effects of the immunocontraceptive GonaCon on individual female cattle and established the effectiveness of GonaCon to induce infertility. We evaluated GonaCon in 34 captive cattle assigned to four groups: Control administered a sham solution; Webbed (surgically sterilized through removal of the oviducts), administered one dose of GonaCon; Webbed, administered one dose of GonaCon and a booster dose three months later, and Treated, administered one dose of GonaCon. The side effects of GonaCon were assessed by monitoring injection site, body weight, body condition, size of lymph nodes, body temperature, and feeding behaviour 1 week and 1, 3, 6, 9 and 12 months after vaccination and by haematological and biochemical variables at vaccination and three months post-vaccination. The effectiveness of GonaCon to cause infertility was monitored by quantifying anti-GnRH antibody titres and by using kits to detect cycling and pregnancy. GonaCon-treated cattle showed no injection site reaction, limping, or abnormal behaviour. No differences were observed in all physiological and welfare indicators between control and vaccinated cattle. All control cattle and 4 of the 12 cattle in the Treated group became pregnant. Cattle administered a booster dose had higher anti-GnRH antibody titres than cattle that received one dose. We concluded that GonaCon does not compromise the animals’ welfare and is effective in reducing fertility in cattle. A booster dose is likely to increase the duration of infertility. Further studies are required to assess the feasibility and costs of immunocontraception for controlling free-roaming cattle populations. PMID:25856283

Immunocontraception for managing feral cattle in Hong Kong.

PubMed

Massei, Giovanna; Koon, Ka-Kei; Benton, Steven; Brown, Richard; Gomm, Matt; Orahood, Darcy S; Pietravalle, Stéphane; Eckery, Douglas C

2015-01-01

Conflicts between human interests and feral cattle in Hong Kong derive from growing numbers of free-roaming cattle. Public antipathy towards lethal population control led the local authorities to consider fertility control to reduce cattle numbers. This study assessed the potential side effects of the immunocontraceptive GonaCon on individual female cattle and established the effectiveness of GonaCon to induce infertility. We evaluated GonaCon in 34 captive cattle assigned to four groups: Control administered a sham solution; Webbed (surgically sterilized through removal of the oviducts), administered one dose of GonaCon; Webbed, administered one dose of GonaCon and a booster dose three months later, and Treated, administered one dose of GonaCon. The side effects of GonaCon were assessed by monitoring injection site, body weight, body condition, size of lymph nodes, body temperature, and feeding behaviour 1 week and 1, 3, 6, 9 and 12 months after vaccination and by haematological and biochemical variables at vaccination and three months post-vaccination. The effectiveness of GonaCon to cause infertility was monitored by quantifying anti-GnRH antibody titres and by using kits to detect cycling and pregnancy. GonaCon-treated cattle showed no injection site reaction, limping, or abnormal behaviour. No differences were observed in all physiological and welfare indicators between control and vaccinated cattle. All control cattle and 4 of the 12 cattle in the Treated group became pregnant. Cattle administered a booster dose had higher anti-GnRH antibody titres than cattle that received one dose. We concluded that GonaCon does not compromise the animals' welfare and is effective in reducing fertility in cattle. A booster dose is likely to increase the duration of infertility. Further studies are required to assess the feasibility and costs of immunocontraception for controlling free-roaming cattle populations.

El efecto de la panfotocoagulación con láser en edema macular diabético con el fotocoagulador Pascal® versus el láser de argón convencional.

PubMed

Mahgoub, Mohamed M; Macky, Tamer A

2017-07-11

Objetivo: El objetivo de este estudio fue comparar el efecto de la panfotocoagulación (PFC) en el edema macular diabético (EMD) en pacientes con retinopatía diabética proliferativa (RDP) con el fotocoagulador Pascal® (FP) vs. un fotocoagulador con láser de argón convencional (FLAC). Métodos: Se aleatorizó el uso de FP o FLAC en ochenta ojos con RDP y EMD con afectación central de la mácula. Ambos grupos tuvieron una evaluación de base de mejor agudeza visual corregida y fueron examinados con tomografía de coherencia óptica y angiografía con fluoresceína. Resultados: El número medio de disparos de láser en los grupos de FP y FLAC fue 1.726,10 y 752,00 en la sesión 1 y 1.589,00 y 830,00 (p < 0,001) en la sesión 2, respectivamente. El grosor foveal central (GFC) medio antes de comenzar el estudio fue 306 ± 100 y 314 ± 98 en los grupos de FP y FLAC, respectivamente. A las 8 semanas, el GFC medio fue 332 ± 116 y 347 ± 111 en los grupos de FP y FLAC, respectivamente (p > 0,05). La MAVC media fue similar durante el periodo de estudio y no hubo ninguna diferencia significativa entre los grupos (p > 0,05). Conclusiones: El FP y el FLAC mostraron efectos similares en el EMD en ojos con RDP y fueron igualmente seguros sin un aumento significativo del GFC. © 2017 S. Karger AG, Basel.

Teratogenic versus mutagenic abnormalities in chironomid larvae exposed to zinc and lead.

PubMed

Martinez, Edward A; Moore, Barry C; Schaumloffel, John; Dasgupta, Nairanjana

2004-08-01

Before chironomid mouthpart deformities can be utilized as indicators of aquatic metal pollution with certainty, it must first be established that deformities are teratogenic and not mutagenic. A laboratory experiment was conducted to assess this question using Zn and Pb as causative agents. Parent populations were reared in sediments spiked with zinc (Zn) or lead (Pb) and their resulting offspring (F1 generation) were reared in clean sediments. The proportions of mouthpart deformities in C. tentans larvae were compared via logistic regression, accounting for time of exposure, between parent and offspring populations. Results indicate that 14% of chironomids from Zn-spiked sediment contained deformed menta and/or mandibles. However, the F1-Zn generation displayed a deformity of 1.7%. Larvae reared in Pb-spiked sediments displayed a deformity frequency of 9% and the F1 generations (F1-Pb a and F1-Pb b) had deformity proportion of 7 and 6%, respectively. We concluded that the deformities caused by Zn stress were morphological because the resulting F1 deformity frequencies declined to control levels. However, deformities caused by Pb appear to be genetic since F1 deformity percentages did not differ from the parent deformity frequency. Because larvae reared in Zn- and Pb-spiked sediments were larger than larvae reared in uncontaminated sediments, we could not conclude that Zn and Pb in the sediments stunted the development of C. tentans.

Inconsistency in the analysis of morphological deformities in chironomidae (Insecta: Diptera) larvae.

PubMed

Salmelin, Johanna; Vuori, Kari-Matti; Hämäläinen, Heikki

2015-08-01

The incidence of morphological deformities of chironomid larvae as an indicator of sediment toxicity has been studied for decades. However, standards for deformity analysis are lacking. The authors evaluated whether 25 experts diagnosed larval deformities in a similar manner. Based on high-quality digital images, the experts rated 211 menta of Chironomus spp. larvae as normal or deformed. The larvae were from a site with polluted sediments or from a reference site. The authors revealed this to a random half of the experts, and the rest conducted the assessment blind. The authors quantified the interrater agreement by kappa coefficient, tested whether open and blind assessments differed in deformity incidence and in differentiation between the sites, and identified those deformity types rated most consistently or inconsistently. The total deformity incidence varied greatly, from 10.9% to 66.4% among experts. Kappa coefficient across rater pairs averaged 0.52, indicating insufficient agreement. The deformity types rated most consistently were those missing teeth or with extra teeth. The open and blind assessments did not differ, but differentiation between sites was clearest for raters who counted primarily absolute deformities such as missing and extra teeth and excluded apparent mechanical aberrations or deviations in tooth size or symmetry. The highly differing criteria in deformity assignment have likely led to inconsistent results in midge larval deformity studies and indicate an urgent need for standardization of the analysis. © 2015 SETAC.

An electromechanical based deformable model for soft tissue simulation.

PubMed

Zhong, Yongmin; Shirinzadeh, Bijan; Smith, Julian; Gu, Chengfan

2009-11-01

Soft tissue deformation is of great importance to surgery simulation. Although a significant amount of research efforts have been dedicated to simulating the behaviours of soft tissues, modelling of soft tissue deformation is still a challenging problem. This paper presents a new deformable model for simulation of soft tissue deformation from the electromechanical viewpoint of soft tissues. Soft tissue deformation is formulated as a reaction-diffusion process coupled with a mechanical load. The mechanical load applied to a soft tissue to cause a deformation is incorporated into the reaction-diffusion system, and consequently distributed among mass points of the soft tissue. Reaction-diffusion of mechanical load and non-rigid mechanics of motion are combined to govern the simulation dynamics of soft tissue deformation. An improved reaction-diffusion model is developed to describe the distribution of the mechanical load in soft tissues. A three-layer artificial cellular neural network is constructed to solve the reaction-diffusion model for real-time simulation of soft tissue deformation. A gradient based method is established to derive internal forces from the distribution of the mechanical load. Integration with a haptic device has also been achieved to simulate soft tissue deformation with haptic feedback. The proposed methodology does not only predict the typical behaviours of living tissues, but it also accepts both local and large-range deformations. It also accommodates isotropic, anisotropic and inhomogeneous deformations by simple modification of diffusion coefficients.

Foldover-free shape deformation for biomedicine.

PubMed

Yu, Hongchuan; Zhang, Jian J; Lee, Tong-Yee

2014-04-01

Shape deformation as a fundamental geometric operation underpins a wide range of applications, from geometric modelling, medical imaging to biomechanics. In medical imaging, for example, to quantify the difference between two corresponding images, 2D or 3D, one needs to find the deformation between both images. However, such deformations, particularly deforming complex volume datasets, are prone to the problem of foldover, i.e. during deformation, the required property of one-to-one mapping no longer holds for some points. Despite numerous research efforts, the construction of a mathematically robust foldover-free solution subject to positional constraints remains open. In this paper, we address this challenge by developing a radial basis function-based deformation method. In particular we formulate an effective iterative mechanism which ensures the foldover-free property is satisfied all the time. The experimental results suggest that the resulting deformations meet the internal positional constraints. In addition to radial basis functions, this iterative mechanism can also be incorporated into other deformation approaches, e.g. B-spline based FFDs, to develop different deformable approaches for various applications. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

The anelastic Ericksen problem: universal eigenstrains and deformations in compressible isotropic elastic solids.

PubMed

Yavari, Arash; Goriely, Alain

2016-12-01

The elastic Ericksen problem consists of finding deformations in isotropic hyperelastic solids that can be maintained for arbitrary strain-energy density functions. In the compressible case, Ericksen showed that only homogeneous deformations are possible. Here, we solve the anelastic version of the same problem, that is, we determine both the deformations and the eigenstrains such that a solution to the anelastic problem exists for arbitrary strain-energy density functions. Anelasticity is described by finite eigenstrains. In a nonlinear solid, these eigenstrains can be modelled by a Riemannian material manifold whose metric depends on their distribution. In this framework, we show that the natural generalization of the concept of homogeneous deformations is the notion of covariantly homogeneous deformations -deformations with covariantly constant deformation gradients. We prove that these deformations are the only universal deformations and that they put severe restrictions on possible universal eigenstrains . We show that, in a simply-connected body, for any distribution of universal eigenstrains the material manifold is a symmetric Riemannian manifold and that in dimensions 2 and 3 the universal eigenstrains are zero-stress.

MODELO PARA EVALUACION DE DERRAMES DE HIDROCARBUROS (HSSM) GUIA DEL USUARIO

EPA Science Inventory

The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible balance between human acti...

A New CT Reconstruction Technique Using Adaptive Deformation Recovery and Intensity Correction (ADRIC)

PubMed Central

Zhang, You; Ma, Jianhua; Iyengar, Puneeth; Zhong, Yuncheng; Wang, Jing

2017-01-01

Purpose Sequential same-patient CT images may involve deformation-induced and non-deformation-induced voxel intensity changes. An adaptive deformation recovery and intensity correction (ADRIC) technique was developed to improve the CT reconstruction accuracy, and to separate deformation from non-deformation-induced voxel intensity changes between sequential CT images. Materials and Methods ADRIC views the new CT volume as a deformation of a prior high-quality CT volume, but with additional non-deformation-induced voxel intensity changes. ADRIC first applies the 2D-3D deformation technique to recover the deformation field between the prior CT volume and the new, to-be-reconstructed CT volume. Using the deformation-recovered new CT volume, ADRIC further corrects the non-deformation-induced voxel intensity changes with an updated algebraic reconstruction technique (‘ART-dTV’). The resulting intensity-corrected new CT volume is subsequently fed back into the 2D-3D deformation process to further correct the residual deformation errors, which forms an iterative loop. By ADRIC, the deformation field and the non-deformation voxel intensity corrections are optimized separately and alternately to reconstruct the final CT. CT myocardial perfusion imaging scenarios were employed to evaluate the efficacy of ADRIC, using both simulated data of the extended-cardiac-torso (XCAT) digital phantom and experimentally acquired porcine data. The reconstruction accuracy of the ADRIC technique was compared to the technique using ART-dTV alone, and to the technique using 2D-3D deformation alone. The relative error metric and the universal quality index metric are calculated between the images for quantitative analysis. The relative error is defined as the square root of the sum of squared voxel intensity differences between the reconstructed volume and the ‘ground-truth’ volume, normalized by the square root of the sum of squared ‘ground-truth’ voxel intensities. In addition to the XCAT and porcine studies, a physical lung phantom measurement study was also conducted. Water-filled balloons with various shapes/volumes and concentrations of iodinated contrasts were put inside the phantom to simulate both deformations and non-deformation-induced intensity changes for ADRIC reconstruction. The ADRIC-solved deformations and intensity changes from limited-view projections were compared to those of the ‘gold-standard’ volumes reconstructed from fully-sampled projections. Results For the XCAT simulation study, the relative errors of the reconstructed CT volume by the 2D-3D deformation technique, the ART-dTV technique and the ADRIC technique were 14.64%, 19.21% and 11.90% respectively, by using 20 projections for reconstruction. Using 60 projections for reconstruction reduced the relative errors to 12.33%, 11.04% and 7.92% for the three techniques, respectively. For the porcine study, the corresponding results were 13.61%, 8.78%, 6.80% by using 20 projections; and 12.14%, 6.91% and 5.29% by using 60 projections. The ADRIC technique also demonstrated robustness to varying projection exposure levels. For the physical phantom study, the average DICE coefficient between the initial prior balloon volume and the new ‘gold-standard’ balloon volumes was 0.460. ADRIC reconstruction by 21 projections increased the average DICE coefficient to 0.954. Conclusion The ADRIC technique outperformed both the 2D-3D deformation technique and the ART-dTV technique in reconstruction accuracy. The alternately solved deformation field and non-deformation voxel intensity corrections can benefit multiple clinical applications, including tumor tracking, radiotherapy dose accumulation and treatment outcome analysis. PMID:28380247

Introduction of a deformable x-ray CT polymer gel dosimetry system

NASA Astrophysics Data System (ADS)

Maynard, E.; Heath, E.; Hilts, M.; Jirasek, A.

2018-04-01

This study introduces the first 3D deformable dosimetry system based on x-ray computed tomography (CT) polymer gel dosimetry and establishes the setup reproducibility, deformation characteristics and dose response of the system. A N-isopropylacrylamide (NIPAM)-based gel formulation optimized for x-ray CT gel dosimetry was used, with a latex balloon serving as the deformable container and low-density polyethylene and polyvinyl alcohol providing additional oxygen barrier. Deformable gels were irradiated with a 6 MV calibration pattern to determine dosimetric response and a dosimetrically uniform plan to determine the spatial uniformity of the response. Wax beads were added to each gel as fiducial markers to track the deformation and setup of the gel dosimeters. From positions of the beads on CT images the setup reproducibility and the limits and reproducibility of gel deformation were determined. Comparison of gel measurements with Monte Carlo dose calculations found excellent dosimetric accuracy, comparable to that of an established non-deformable dosimetry system, with a mean dose discrepancy of 1.5% in the low-dose gradient region and a gamma pass rate of 97.9% using a 3%/3 mm criterion. The deformable dosimeter also showed good overall spatial dose uniformity throughout the dosimeter with some discrepancies within 20 mm of the edge of the container. Tracking of the beads within the dosimeter found that sub-millimetre setup accuracy is achievable with this system. The dosimeter was able to deform and relax when externally compressed by up to 30 mm without sustaining any permanent damage. Internal deformations in 3D produced average marker movements of up to 12 mm along the direction of compression. These deformations were also shown to be reproducible over 100 consecutive deformations. This work has established several important characteristics of a new deformable dosimetry system which shows promise for future clinical applications, including the validation of deformable dose accumulation algorithms.

High School Students' Previous Knowledge about the Stars. (Spanish Title: Conocimientos Previos de Estudiantes de Secundaria Acerca de Las Estrellas.) O Conhecimento Prévio de Alunos do Ensino Médio sobre as Estrelas

NASA Astrophysics Data System (ADS)

Iachel, Gustavo

2011-12-01

Based on the readings of articles related to Astronomy Education published in Brazil, it was noticed a lack of research on previous knowledge of students about the physical characteristics of stars, a fact that motivated us to develop this study. Previous knowledge of 125 students (approximated 15 years old) constituted the study sample; data was collected through written questionnaires (Appendix A) for analysis. From the content analysis of these responses it was possible to achieve some inferences as, for example, many students have some difficult to develop an explanatory model on the functioning of a star; there are few who say that the stars have a certain length of existence; some students have said that stars have tips; few recognize that a star is formed by a mass of gas; some previous knowledge come from purely visual aspects; furthermore, some students do not have the habit of observing nature in detail. We see this research as a reference in which science teachers can recognize the importance of previous knowledge for practice teaching and acquire resources for planning their lessons. De la lectura de artículos relacionados con la Educación en Astronomía publicados en el Brasil, se encuentra una falta de investigaciones acerca del conocimiento previo de los estudiantes sobre las características físicas de las estrellas, hecho que nos motivó a desarrollar este estudio. Los datos analizados se obtuvieron al aplicar un cuestionario a 125 estudiantes de secundaria, para posteriormente realizar un análisis de contenido, tal cuestionario se presenta en el Anexo A. Al realizar el análisis de contenido de las respuestas obtenidas, fue posible hacer algunas inferencias, como por ejemplo; muchos estudiantes tienen dificultades para desarrollar un modelo explicativo acerca del funcionamiento de una estrella; pocos estudiantes dicen que las estrellas tienen un cierto tiempo de vida; algunos estudiantes imaginan que las estrellas tienen puntas; pocos reconocen que una estrella es formada por una masa de gas; varios conocimientos previos parten de aspectos puramente visuales; por otro lado, los estudiantes no tienen el hábito de observar la naturaleza detalladamente, entre otros problemas. Vemos esta investigación como una probable fuente de referencia en la que los profesores de ciencias pueden reconocer la importancia del conocimiento previo, y la forma como interfieren con su práctica de enseñanza, además de la adquisición de recursos para la planificación de sus clases. Com base em leituras de artigos relacionados ao ensino de Astronomia publicados no Brasil, verificou-se a inexistência de investigações sobre o conhecimento prévio de estudantes acerca das características físicas das estrelas, fato que nos motivou a desenvolver a pesquisa apresentada. Os conhecimentos prévios de 125 estudantes do primeiro ano do ensino médio constituíram os dados do estudo, os quais foram inferidos através da análise das respostas cedidas em questionários impressos (Apêndice A). A partir da análise de conteúdo dessas respostas tornou-se possível realizar algumas inferências como, por exemplo: vários estudantes possuem dificuldade em elaborar um modelo explicativo sobre o funcionamento de uma estrela; são poucos os que dizem que as estrelas possuem certo tempo de existência; alguns alunos as imaginam com pontas; poucos reconhecem que uma estrela é formada por uma massa de gás; vários conhecimentos prévios partem de aspectos meramente visuais; ainda assim, os estudantes não possuem o hábito de observar a natureza mais detalhadamente, entre outras. Vemos essa pesquisa como uma provável fonte de consulta na qual os professores de ciências poderão, além de reconhecer a importância dos conhecimentos prévios para o ensino e como eles interferem em sua prática, adquirir subsídios para o planejamento de suas aulas.

Prototype of a computerized scale for the active search for potential organ donors.

PubMed

Ludwig, Érika Fernanda Dos Santos Bezerra; Pereira, Marta Cristiane Alves; Martinez, Yolanda Dora Évora; Mendes, Karina Dal Sasso; Rossaneis, Mariana Angela

2017-09-12

to develop a prototype of a computerized scale for the active search for potential organ and tissue donors. methodological study, with the analysis of 377 electronic medical records of patients who died due to encephalic death or cardiorespiratory arrest in the intensive care units of a tertiary hospital. Among the deaths due to cardiorespiratory arrest, the study aimed to identify factors indicating underreported encephalic death cases. The Acute Physiology and Chronic Health Evaluation II and Sepsis Related Organ Failure Assessment severity indexes were applied in the protocols. Based on this, a scale was built and sent to five experts for assessment of the scale content, and subsequently, it was computerized by using a prototyping model. 34 underreported encephalic death cases were identified in the medical records of patients with cardiorespiratory arrest. Statistically significant differences were found in the Wilcoxon test between the scores of hospital admissions in the intensive care unit and the opening of the encephalic death protocol for both severity indexes. the prototype was effective for identifying potential organ donors, as well as for the identification of the degree of organ dysfunction in patients with encephalic death. desenvolver protótipo de escala informatizada para busca ativa de potenciais doadores de órgãos e tecidos. pesquisa metodológica, com análise de 377 prontuários eletrônicos de pacientes que evoluíram a óbito, por morte encefálica, ou parada cardiorrespiratória, nas unidades de terapia intensiva de hospital terciário. Nos óbitos por parada cardiorrespiratória, buscou-se identificar fatores que indicassem subnotificação de morte encefálica. Nos protocolos, foram aplicados os índices de gravidade Acute Physiology and Chronic Health Evaluation II e Sepsis Related Organ Failure Assessment. A partir disso, construiu-se a escala que foi encaminhada a cinco especialistas, para avaliação de conteúdo, e, posteriormente, foi informatizada por modelo de prototipação. foram identificadas 34 subnotificações de morte encefálica nos prontuários dos casos de parada cardiorrespiratória. O teste de Wilcoxon demonstrou diferença estatisticamente significativa entre os escores de admissão em unidade de terapia intensiva e abertura do protocolo de morte encefálica, para ambos os índices de gravidade. o protótipo foi efetivo para identificação de potenciais doadores, bem como o grau de disfunção orgânica de pacientes em morte encefálica. desarrollar un prototipo de escala informatizada para la búsqueda activa de potenciales donantes de órganos y tejidos. investigación metodológica, con el análisis de 377 registros médicos electrónicos de pacientes, que fallecieron por muerte encefálica o paro cardiorrespiratorio, en las unidades de cuidados intensivos de un hospital terciario. Entre las muertes por paro cardiorrespiratorio, se buscó identificar los factores que indicasen subnotificación de muerte encefálica. Las puntuaciones de los índices de gravedad Acute Physiology and Chronic Health Evaluation II y Sepsis Related Organ Failure Assessment se aplicaron en los protocolos. A partir de eso, la escala fue construida y enviada a cinco expertos para la evaluación del contenido, y posteriormente, fue informatizada mediante un modelo de prototipación. se identificaron 34 casos de subnotificación de muerte encefálica en los registros médicos de los casos de paro cardiorrespiratorio. Se encontraron diferencias estadísticamente significativas en la prueba de Wilcoxon, entre las puntuaciones de los ingresos hospitalarios en unidad de cuidados intensivos y apertura del protocolo de muerte encefálica para ambos índices de gravedad. el prototipo fue eficaz para la identificación de potenciales donantes, así como para la identificación del grado de disfunción orgánica en pacientes con muerte encefálica.

Psychometric properties of the Exercise Benefits/Barriers Scale in Mexican elderly women.

PubMed

Enríquez-Reyna, María Cristina; Cruz-Castruita, Rosa María; Ceballos-Gurrola, Oswaldo; García-Cadena, Cirilo Humberto; Hernández-Cortés, Perla Lizeth; Guevara-Valtier, Milton Carlos

2017-06-05

analyze and assess the psychometric properties of the subscales in the Spanish version of the Exercise Benefits/Barriers Scale in an elderly population in the Northeast of Mexico. methodological study. The sample consisted of 329 elderly associated with one of the five public centers for senior citizens in the metropolitan area of Northeast Mexico. The psychometric properties included the assessment of the Cronbach's alpha coefficient, the Kaiser Meyer Olkin coefficient, the inter-item correlation, exploratory and confirmatory factor analysis. in the principal components analysis, two components were identified based on the 43 items in the scale. The item-total correlation coefficient of the exercise benefits subscale was good. Nevertheless, the coefficient for the exercise barriers subscale revealed inconsistencies. The reliability and validity were acceptable. The confirmatory factor analysis revealed that the elimination of items improved the goodness of fit of the baseline scale, without affecting its validity or reliability. the Exercise Benefits/Barriers subscale presented satisfactory psychometric properties for the Mexican context. A 15-item short version is presented with factorial structure, validity and reliability similar to the complete scale. analisar e avaliar as propriedades psicométricas das subescalas que compõem a versão em espanhol da Escala de Benefícios/Barreiras para o Exercício em uma população idosa do nordeste do México. estudo metodológico. A amostra abrangeu 329 idosas adstritas a uma das cinco casas de convivência públicas da área metropolitana do Nordeste mexicano. As propriedades psicométricas incluíram a avaliação do coeficiente alfa de Cronbach, o coeficiente Kaiser-Meyer-Olkin, a correlação inter-itens, análise fatorial exploratória e confirmatória. na análise de componentes principais, foram identificados dois componentes a partir dos 43 itens da escala. O coeficiente de correlação item-total da subescala benefícios do exercício foi adequado. Porém, o coeficiente da subescala barreiras para o exercício mostrou inconsistências. A confiabilidade e validade foram aceitáveis. A análise fatorial confirmatória revelou que a eliminação de itens melhorava a qualidade de ajuste do modelo basal da escala sem afetar sua validade ou confiabilidade. a Escala de Benefícios/Barreiras para o Exercício apresenta parâmetros psicométricos satisfatórios para o contexto mexicano. Apresenta-se uma versão reduzida de 15 itens com estrutura fatorial, validade e confiabilidade similares aos da escala completa. analizar y evaluar las propiedades psicométricas de las subescalas que componen la versión en español de la Escala Beneficios/Barreras para el Ejercicio en población anciana del noreste de México. estudio metodológico. La muestra estuvo constituida por 329 ancianas adscritas a alguna de cinco casas-club públicas del área metropolitana del noreste de México. Las propiedades psicométricas incluyeron la evaluación del coeficiente alfa de Cronbach, el coeficiente Kaiser Meyer Olkin, la correlación inter-ítem, análisis factorial exploratorio y confirmatorio. en el análisis de componentes principales se identificaron dos componentes a partir de los 43 ítems de la escala. El coeficiente de correlación ítem-total de la subescala beneficios del ejercicio fue bueno. Sin embargo, el de barreras para el ejercicio mostró inconsistencias. La confiabilidad y validez fueron aceptables. Con el análisis factorial confirmatorio se identificó que la eliminación de ítems mejoraba la calidad de ajuste del modelo basal de la escala sin afectar su validez ni confiabilidad. la Escala Beneficios/Barreras para el Ejercicio presenta parámetros psicométricos satisfactorios para el contexto mexicano. Se presenta una versión corta de 15 ítems con estructura factorial, validez y confiabilidad similares a los de la escala completa.

Active Beam Shaping System and Method Using Sequential Deformable Mirrors

NASA Technical Reports Server (NTRS)

Pueyo, Laurent A. (Inventor); Norman, Colin A. (Inventor)

2015-01-01

An active optical beam shaping system includes a first deformable mirror arranged to at least partially intercept an entrance beam of light and to provide a first reflected beam of light, a second deformable mirror arranged to at least partially intercept the first reflected beam of light from the first deformable mirror and to provide a second reflected beam of light, and a signal processing and control system configured to communicate with the first and second deformable mirrors. The first deformable mirror, the second deformable mirror and the signal processing and control system together provide a large amplitude light modulation range to provide an actively shaped optical beam.

Unclassified congenital deformities of the external ear.

PubMed

Vathulya, Madhubari

2018-01-01

Congenital ear deformities are a common entity. They are found in isolation or as a part of syndrome in patients. They may involve the external, middle or inner ear or in any of these combinations. Three patients of different ages presented with deformities including mirror image duplication of the superior auricle, unclassified deformities of ear lobule (wavy lobule) and deformity of superior auricle with unclassified variety of lateral ear pit. This article highlights that there are further cases of ear deformities that are noticed in the general population who come for cosmetic correction, and hence, there is a need for further modifying the classification of ear deformities.

Tanker Airlift Control Elements (TALCEs) and Contingency Response Units (CRUs): Does Air Force Operational Doctrine Need to Change?

DTIC Science & Technology

2001-06-01

34 Table 4. Pros and Cons of Alternate Solutions ................................................................. 43 viii Abstract...the best structure for the Air Force goes beyond the scope of this paper. The table below summarizes the pros and cons of the three alternate...solutions presented. Table 4. Pros and Cons of Alternate Solutions Solution Pros Cons No CRU Centralized management and training, few MOG limitations

Muscle fiber characteristics and performance correlates of male Olympic-style weightlifters.

PubMed

Fry, Andrew C; Schilling, Brian K; Staron, Robert S; Hagerman, Fredrick C; Hikida, Robert S; Thrush, John T

2003-11-01

Biopsies fro the vastus lateralis muscle of male weightlifters (WL; n=6; X +/- SE, age=27.0 +/- 2.1 years), and non-weight-trained men (CON; n=7; age=27.0 +/- 2.0 years) were compared for fiber types, myosin heavy chain (MHC) and titin content, and fiber type-specific capillary density. Differences (p<0.05) were observed for percent fiber types IIC (WL=0.4 +/- 0.2, CON=2.4 +/- 0.8); IIA (WL=50.5 +/- 3.2, CON=26.9 +/- 3.7); and IIB (WL=1.7 +/- 1.4, CON=21.0 +/- 5.3), as well as percent MHC IIa (WL=65.3 +/- 2.4, CON=52.1 +/- 4.2) and percent MHC IIB (WL=0.9 +/- 0.9; CON=18.2 +/- 6.1). All WL exhibited only the titin-1 isoform. Capillary density (caps.mm(-2)) for all fiber types combined was greater for the CON subjects (WL=192.7 +/- 17.3; CON=262.9 +/- 26.3), due primarily to a greater capillary density in the IIA fibers. Weightlifting performances and vertical jump power were correlated with type II fiber characteristics. These results suggest that successful weightlifting performance is not dependent on IIB fibers, and that weightlifters exhibit large percentages of type IIA muscle fibers and MHC IIa isoform content.

ComSciCon: The Communicating Science Workshop for Graduate Students

NASA Astrophysics Data System (ADS)

Sanders, Nathan; Drout, Maria; Kohler, Susanna; Cook, Ben; ComSciCon Leadership Team

2018-01-01

ComSciCon (comscicon.com) is a national workshop series organized by graduate students, for graduate students, focused on leadership and training in science communication. Our goal is to empower young scientists to become leaders in their field, propagating appreciation and understanding of research results to broad and diverse audiences. ComSciCon attendees meet and interact with professional communicators, build lasting networks with graduate students in all fields of science and engineering from around the country, and write and publish original works. ComSciCon consists of both a flagship national conference series run annually for future leaders in science communication, and a series of regional and specialized workshops organized by ComSciCon alumni nationwide. We routinely receive over 1000 applications for 50 spots in our national workshop. Since its founding in 2012, over 300 STEM graduate students have participated in the national workshop, and 23 local spin-off workshops have been organized in 10 different locations throughout the country. This year, ComSciCon is working to grow as a self-sustaining organization by launching as an independent 501(c)(3) non-profit. In this poster we will discuss the ComSciCon program and methods, our results to date, potential future collaborations between ComSciCon and AAS, and how you can become involved.

κ-deformed Dirac oscillator in an external magnetic field

NASA Astrophysics Data System (ADS)

Chargui, Y.; Dhahbi, A.; Cherif, B.

2018-04-01

We study the solutions of the (2 + 1)-dimensional κ-deformed Dirac oscillator in the presence of a constant transverse magnetic field. We demonstrate how the deformation parameter affects the energy eigenvalues of the system and the corresponding eigenfunctions. Our findings suggest that this system could be used to detect experimentally the effect of the deformation. We also show that the hidden supersymmetry of the non-deformed system reduces to a hidden pseudo-supersymmetry having the same algebraic structure as a result of the κ-deformation.

ConSpeciFix: Classifying prokaryotic species based on gene flow.

PubMed

Bobay, Louis-Marie; Ellis, Brian Shin-Hua; Ochman, Howard

2018-05-16

Classification of prokaryotic species is usually based on sequence similarity thresholds, which are easy to apply but lack a biologically-relevant foundation. Here, we present ConSpeciFix, a program that classifies prokaryotes into species using criteria set forth by the Biological Species Concept, thereby unifying species definition in all domains of life. ConSpeciFix's webserver is freely available at www.conspecifix.com. The local version of the program can be freely downloaded from https://github.com/Bobay-Ochman/ConSpeciFix. ConSpeciFix is written in Python 2.7 and requires the following dependencies: Usearch, MCL, MAFFT and RAxML. ljbobay@uncg.edu.

Self-efficacy, pros, and cons as variables associated with adjacent stages of change for regular exercise in Japanese college students.

PubMed

Horiuchi, Satoshi; Tsuda, Akira; Kobayashi, Hisanori; Fallon, Elizabeth A; Sakano, Yuji

2017-07-01

This study examined self-efficacy (confidence to exercise), pros (exercise's advantages), and cons (exercise's disadvantages) as variables associated across the transtheoretical model's six stages of change in 403 Japanese college students. A series of logistic regression analyses were conducted. Results showed that higher pros and lower cons were associated with being in contemplation compared to precontemplation. Lower cons were associated with being in preparation compared to contemplation. Higher self-efficacy was associated with being in action compared to preparation as well as being in maintenance compared to action. Lower cons were associated with being in termination compared to maintenance.

Mejoras en la exactitud del reloj de ángulo horario del telescopio de 2,15 mts de CASLEO

NASA Astrophysics Data System (ADS)

Aballay, J. L.; Pereyra, P. F.; Marún, A. H.

Para aumentar la exactitud en el control del ángulo horario del telescopio, se está implementando el uso de un reloj con una precisión de 1/100 seg. En conjunto con el encoder que otorga la posición con un acierto de 0,012 seg. de arco, se podrá implementar otro dígito en el reloj de ángulo horario con la posibilidad de ver las décimas. Esto, sumado a la precisión ya lograda en declinación, permitirá realizar offsets con mayor exactitud.

Do hospital chief executive officers extract rents from Certificate of Need laws?

PubMed

Eichmann, Traci L; Santerre, Rexford E

2011-01-01

Prior research suggests that Certificate of Need (CON) laws reduce competition in the hospital services industry. As a result, this study empirically investigates if not-for-profit hospital chief executive officers (CEOs) are able to extract rents from CON laws in the form of higher compensation. A sample of 256 not-for-profit hospital CEOs in states with and without CON laws and data for 2007 are used in the empirical analysis. The study considers the endogenous nature of a CON law and allows such a law to indirectly affect CEO compensation through its impact on the number of hospitals and beds. The multiple regression results indicate that special and public interests both motivate the decision of a state to maintain a CON law. CON laws are shown to reduce the number of beds at the typical hospital by 12 percent, on average, and the number of hospitals per 100,000 persons by 48 percent. These reductions ultimately lead urban hospital CEOs in states with CON laws to extract economic rents of $91,000 annually.

Effect of cold deformation on the electrochemical behaviour of 304L stainless steel in contaminated sulfuric acid environment

NASA Astrophysics Data System (ADS)

Luo, Hong; Su, Huaizhi; Ying, Guobing; Dong, Chaofang; Li, Xiaogang

2017-12-01

The effect of cold deformation on the microstructure and electrochemical corrosion behaviour of 304L stainless steel in contaminated sulfuric acid solutions (simulated proton exchange membrane fuel cells environments) were evaluated using electron backscatter diffraction analyses, electrochemical measurements, and surface analyses. The internal microstructure,including the grain sizes, angles of the grain boundaries, low coincidence site lattice boundaries, and phase transformations, was changed due to the cold deformation. No noticeable modifications of the pitting corrosion potential were observed during the various deformations, except for a slight enhancement in the passive current density with an increase in the deformation. The CrO3 and metal Ni species in the passive film were investigated after deformation. After heavy deformation (greater than 60%), nickel oxides were detected. Moreover, the Cr/Fe and O2-/OH- ratios in the passive film were higher before deformation, and they decreased with an increase in the deformation level.

Research on wire rope deformation distribution of WR-CVT

NASA Astrophysics Data System (ADS)

Zhang, Wu; Guo, Wei; Zhang, Chuanwei; Lu, Zhengxiong; Xu, Xiaobin

2017-07-01

A wire rope continuously variable transmissions (WR-CVT) has been introduced in the paper, in view of its less research, this paper mainly studied the deformation distribution of 6×7+IWS bending wire rope. The results shown that in the same section, half of the side strands are in a stretched state and half are in a compressed state. When the transmission ratio i=2.35, the maximum deformation and the minimum deformation are decrease when section U1 to U2, U3 transition. Wire deformation distribution when the transmission ratio i=0.42 is similar to that of i=0.2.35. Wire deformation amount and the deformation difference decrease as the transmission ratio decreases, this shows that the increase in the bending radius of the wire will make the wire deformation more uniform, and the reduction of the deformation difference will also reduce the wear. This study provides a basis for the study of fatigue and wears failure of WR-CVT components.

Origin and evolution of phyllosilicate deformation bands in the poorly lithified sandstones of the Rio do Peixe Basin, NE Brazil

NASA Astrophysics Data System (ADS)

Nogueira, Francisco; Nicchio, Matheus; Balsamo, Fabrizio; Bezerra, Francisco; Souza, Jorge; Carvalho, Bruno; Storti, Fabrizio

2017-04-01

In this work we describe the genetic processes and the microstructural evolution of phylossilicate deformation bands developed in poorly lithified, high porosity sandstones of the Rio do Peixe Basin, Northeast Brazil. The studied deformation bands occur in damage zones of NE-SW and NW-SE transtensional faults that exhibit well developed anastomosed clusters, with a thickness varying from tens of centimeters to 1 meter. The Host rocks are arkosic to lithic arkosic coarse sandstones to fine conglomerate and with less than 1% of clay content in the matrix. Based on (i) field observations, (ii) clay amount in deformation band cores and (iii) clay mineral arrangements in deformation bands cores, we identified two types of phyllosilicate deformation bands: (1) clay smearing deformation bands and (2) phyllosilicate deformation bands formed by clay authigenesis. The former occur only in fault zones that cut across clay-rich layers and are characterized by 45-50% of clay content. Single element chemical analysis indicates that the composition of clay minerals in clay smearing deformation bands is similar to that of clay-rich layers in the host rocks. The dominant deformation mechanism is particulate flow, which produces preferential alignments of grains and clay minerals. Only subordinate cataclasis occurs. Based on microstructural fabrics, three evolutionary stages can be identified for phyllosilicate deformation bands formed by clay authigenesis. The first one is characterized by preferentially cataclasis and weathering of feldspars. Clay concentration is relatively low, reaching 15-20%, with preferential concentration where crushed feldspar abundance is higher. The second stage is characterized by clay migration within deformation bands, to form continuous films with more than 20-25% of clay concentration. In the last stage clay mineral fabric re-organization occurs, forming well a developed S-C foliation. Clay concentration exceeds 35%. Single element chemical analysis indicates that the only external element present in phyllosilicate deformation bands formed by clay authigenesis is iron oxide. This feature suggests formation at very shallow depth, in the vadose zone where fluid flow preferentially occurs by capillarity in deformation band cores. Petrophysical analysis shows that both types of phyllosilicate deformation bands have high sealing potential. Clay smearing deformation bands reduce rock permeability by three orders of magnitude whereas phyllosilicate deformation bands formed by authigenesis causes permeability reduction of about two orders of magnitude with respect to the corresponding host rock.

Deformation behavior of Nb nanowires in TiNiCu shape memory alloy matrix

DOE PAGES

Jiang, Daqiang; Liu, Yinong; Yu, Cun; ...

2015-08-18

An in-situ nanowire Nb/TiNiCu composite is fabricated based on the concept of strain under-matching between a phase transforming matrix and high strength nanomaterials. The deformation behavior of the Nb nanowire was investigated by means of in-situ synchrotron X-ray diffraction when the TiNiCu matrix underwent different deformation modes. The maximum lattice strain of the Nb nanowires was about 5% when the matrix deformed via martensitic transformation or 1% when deforming plastically by dislocation slip. As a result, the Nb nanowires showed a lattice strain of 3.5% when the matrix deformed in the mixed mode of plastic deformation and martensitic transformation, whichmore » means that the occurrence of plastic deformation does not impede load transfer from the matrix to the nanowires.« less

Sparse 4D TomoSAR imaging in the presence of non-linear deformation

NASA Astrophysics Data System (ADS)

Khwaja, Ahmed Shaharyar; ćetin, Müjdat

2018-04-01

In this paper, we present a sparse four-dimensional tomographic synthetic aperture radar (4D TomoSAR) imaging scheme that can estimate elevation and linear as well as non-linear seasonal deformation rates of scatterers using the interferometric phase. Unlike existing sparse processing techniques that use fixed dictionaries based on a linear deformation model, we use a variable dictionary for the non-linear deformation in the form of seasonal sinusoidal deformation, in addition to the fixed dictionary for the linear deformation. We estimate the amplitude of the sinusoidal deformation using an optimization method and create the variable dictionary using the estimated amplitude. We show preliminary results using simulated data that demonstrate the soundness of our proposed technique for sparse 4D TomoSAR imaging in the presence of non-linear deformation.

NMR study on mechanisms of ionic polymer-metal composites deformation with water content

NASA Astrophysics Data System (ADS)

Zhu, Zicai; Chen, Hualing; Wang, Yongquan; Luo, Bin; Chang, Longfei; Li, Bo; Chen, Luping

2011-10-01

Ionic polymer-metal composites (IPMCs) exhibit a large dynamic bending deformation under exterior electric field. The states and proportions of water within the IPMCs have great effect on the IPMCs deformation properties. This letter investigates the influence of the proportion changes of different types of water on the deformation, which may disclose the working mechanisms of the IPMCs. We give a deformation trend of IPMCs with the reduction of water content firstly. Then by the method of nuclear magnetic resonance, various water types (water bonded to sulfonates, loosely bound water and free water) of IPMCs and their proportions are investigated in the drying process which corresponds to their different deformation states. It is obtained that the deformation properties of IPMCs depend strongly on their water content and the excess free water is responsible for the relaxation deformation.

Prevalence of skeletal deformity due to nutritional rickets in children between 1 and 18 years in tea garden community.

PubMed

Chabra, Tarun; Tahbildar, Pranjal; Sharma, Ayush; Boruah, Sushanta; Mahajan, Rajat; Raje, Amrut

2016-01-01

The present study was undertaken to find out the prevalence of skeletal deformity due to nutritional rickets in children aged 1-18 years in tea garden community in Dibrugarh District of Assam. It was a cross-sectional study and two-stage cluster sampling was used. In the selected tea gardens, all the children aged 1-18 years were screened for skeletal deformity by house-to-house visit. The overall prevalence of skeletal deformity was 2.7 per thousand. Majority of children with deformities (57.27%) were between 7 and 12 years of age. Widening of wrists and ankle was the most frequent symptom (53.8%). Most of the children with deformity had moderate malnutrition (77.27%). Most of the children with skeletal deformity belong to lower (v) (45.45%) grade of Kuppuswamy's grading scale. Bilateral genu valgus deformity (54.54%) and bilateral genu varum (25.92%) deformity were the most common deformities. Widening of wrists and ankle was the most frequent symptom (61.66%). Of the 16,274 tea garden children included in our study (male and female) in the age group 1-18 years, 44 had skeletal deformity due to nutritional rickets. The prevalence of skeletal deformity due to nutritional rickets was found to be 2.7 per thousand children, which are significantly higher when compared with the only other such study, which was on general population in Bangladesh.

Estimating Tunnel Strain in the Weak and Schistose Rock Mass Influenced by Stress Anisotropy: An Evaluation Based on Three Tunnel Cases from Nepal

NASA Astrophysics Data System (ADS)

Panthi, Krishna Kanta; Shrestha, Pawan Kumar

2018-06-01

Total plastic deformation in tunnels passing through weak and schistose rock mass consists of both time-independent and time-dependent deformations. The extent of this total deformation is heavily influenced by the rock mass deformability properties and in situ stress condition prevailing in the area. If in situ stress is not isotropic, the deformation magnitude is not only different along the longitudinal alignment but also along the periphery of the tunnel wall. This manuscript first evaluates the long-term plastic deformation records of three tunnel projects from the Nepal Himalaya and identifies interlink between the time-independent and time-dependent deformations using the convergence law proposed by Sulem et al. (Int J Rock Mech Min Sci Geomech 24(3):145-154, 1987a, Int J Rock Mech Min Sci Geomech 24(3):155-164, 1987b). Secondly, the manuscript attempts to establish a correlation between plastic deformations (tunnel strain) and rock mass deformable properties, support pressure and in situ stress conditions. Finally, patterns of time-independent and time-dependent plastic deformations are also evaluated and discussed. The long-term plastic deformation records of 24 tunnel sections representing four different rock types of three different headrace tunnel cases from Nepal Himalaya are extensively used in this endeavor. The authors believe that the proposed findings will be a step further in analysis of plastic deformations in tunnels passing through weak and schistose rock mass and along the anisotropic stress conditions.

Electron backscatter and X-ray diffraction studies on the deformation and annealing textures of austenitic stainless steel 310S

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nezakat, Majid, E-mail: majid.nezakat@usask.ca

We studied the texture evolution of thermo-mechanically processed austenitic stainless steel 310S. This alloy was cold rolled up to 90% reduction in thickness and subsequently annealed at 1050 °C. At the early stages of deformation, strain-induced martensite was formed from deformed austenite. By increasing the deformation level, slip mechanism was found to be insufficient to accommodate higher deformation strains. Our results demonstrated that twinning is the dominant deformation mechanism at higher deformation levels. Results also showed that cold rolling in unidirectional and cross rolling modes results in Goss/Brass and Brass dominant textures in deformed samples, respectively. Similar texture components aremore » observed after annealing. Thus, the annealing texture was greatly affected by texture of the deformed parent phase and martensite did not contribute as it showed an athermal reversion during annealing. Results also showed that when the fraction of martensite exceeds a critical point, its grain boundaries impeded the movement of austenite grain boundaries during annealing. As a result, recrystallization incubation time would increase. This caused an incomplete recrystallization of highly deformed samples, which led to a rational drop in the intensity of the texture components. - Highlights: •Thermo-mechanical processing through different cold rolling modes can induce different textures. •Martensite reversion is athermal during annealing. •Higher fraction of deformation-induced martensite can increase the annealing time required for complete recrystallization. •Annealing texture is mainly influenced by the deformation texture of austenite.« less

Single step purification of concanavalin A (Con A) and bio-sugar production from jack bean using glucosylated magnetic nano matrix.

PubMed

Kim, Ho Myeong; Cho, Eun Jin; Bae, Hyeun-Jong

2016-08-01

Jack bean (JB, Canavalia ensiformis) is the source of bio-based products, such as proteins and bio-sugars that contribute to modern molecular biology and biomedical research. In this study, the use of jack bean was evaluated as a source for concanavalin A (Con A) and bio-sugar production. A novel method for purifying Con A from JBs was successfully developed using a glucosylated magnetic nano matrix (GMNM) as a physical support, which facilitated easy separation and purification of Con A. In addition, the enzymatic conversion rate of 2% (w/v) Con A extracted residue to bio-sugar was 98.4%. Therefore, this new approach for the production of Con A and bio-sugar is potentially useful for obtaining bio-based products from jack bean. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Review of Staphylococcal Cassette Chromosome mec (SCCmec) Types in Coagulase-Negative Staphylococci (CoNS) Species.

PubMed

Saber, Huda; Jasni, Azmiza Syawani; Jamaluddin, Tengku Zetty Maztura Tengku; Ibrahim, Rosni

2017-10-01

Coagulase-negative staphylococci (CoNS) are considered low pathogenic organisms. However, they are progressively causing more serious infections with time because they have adapted well to various antibiotics owing to their ability to form biofilms. Few studies have been conducted on CoNS in both, hospital and community-acquired settings, especially in Malaysia. Thus, it is important to study their species and gene distributions. A mobile genetic element, staphylococcal cassette chromosome mec (SCC mec ), plays an important role in staphylococci pathogenesis. Among CoNS, SCC mec has been studied less frequently than Staphylococcus aureus (coagulase-positive staphylococci). A recent study (8) conducted in Malaysia successfully detected SCC mec type I to VIII as well as several new combination patterns in CoNS species, particularly Staphylococcus epidermidis . However, data are still limited, and further research is warranted. This paper provides a review on SCC mec types among CoNS species.

Influence of eccentric actions on the metabolic cost of resistance exercise

NASA Technical Reports Server (NTRS)

Dudley, Gary A.; Golden, Catherine L.; Tesch, Per A.; Harris, Robert T.; Buchanan, Paul

1991-01-01

The contributions of concentric (con) and eccentric (ecc) muscle actions are evaluated with respect to increasing the metabolic cost of resistance exercise. Male subjects perform leg exercise with either con and ecc actions or only con actions while the net energy cost of the exercise is measured by oxygen consumption data. In both groups, the con actions require 290 J/kg body weight of total work, with an energy cost of 0.003 cal/J. The energy costs for the con/ecc actions of the second group is increased by 14 percent. The metabolic cost of leg exercise is concluded to be primarily generated by the con leg actions, and ecc leg actions increase the resistance with only a slight increase in required energy. The findings are significant for practical applications that emphasize the conservation of energy expenditure during exercise in spacecraft environments.

The effects of different flooring types on the behavior, health, and welfare of finishing beef steers.

PubMed

Elmore, M R P; Elischer, M F; Claeys, M C; Pajor, E A

2015-03-01

Raising beef cattle on concrete floors can negatively impact their welfare by increasing joint swelling and body lesions, as well as abnormalities in resting behavior and postural changes. We hypothesized that the addition of rubber mats to concrete pens would improve beef cattle welfare by improving performance, health, hygiene, and resting behavior. Forty-eight crossbred Angus steers were housed in pens of 4 and randomly assigned to a single flooring treatment: (1) fully slatted concrete (CON), (2) fully slatted rubber mat (SLAT), or (3) solid rubber mat (SOLID; 60% of pen floor) from 36 to 48 wk of age. Weight, ADG, lesions, gait score, joint swelling, and animal and pen cleanliness were collected every 2 wk. Behavioral time budgets and frequency of postural changes (an indicator of floor traction and comfort) were collected at 0, 6, and 12 wk. No differences in weight gain or ADG were observed. Steers on SOLID flooring (0.80 ± 0.08) showed increased lesions compared to SLAT (0.38 ± 0.08) and CON (0.37 ± 0.08; both, = 0.05); however, there was no difference between SLAT and CON. SLAT steers (1.69 ± 0.04) showed a reduced gait score compared to SOLID (1.95 ± 0.04) and CON (1.98 ± 0.04; both, < 0.05), but SOLID and CON did not differ. Steers on SLAT flooring had less joint swelling (both knees and hocks) compared to SOLID and CON (all comparisons, < 0.05), but SOLID and CON did not differ. Steers on SOLID (3.64 ± 0.05) flooring were dirtier than those on SLAT (2.27 ± 0.05) and CON (2.19 ± 0.05; both, < 0.001), whereas SLAT and CON were similar. Additionally, SOLID and SLAT pens were less clean than CON pens ( < 0.001 and = 0.094, respectively), and SOLID was less clean than SLAT ( < 0.001). Time budget behavior was affected by treatment ( = 0.043), where SOLID differed from CON and SLAT (both, < 0.05). Steers on SOLID flooring preferred to rest on the rubber mat vs. slatted concrete ( = 0.001). Steers on SLAT flooring changed their posture more frequently than those on SOLID and CON flooring (both, < 0.05), but SOLID and CON did not differ. Compared to CON steers, SOLID steers showed an increase in lesions and a reduction in cleanliness, whereas SLAT steers showed a decrease in gait score and joint swelling and an increase in postural changes. Combined, these data suggest that the addition of slatted rubber mats to concrete pens may improve beef cattle welfare.

Monotonous and stepwise character of deformation accumulation as a hierarchically organized process under high-temperature deformation of aluminum-magnesium alloy

NASA Astrophysics Data System (ADS)

Makarov, S. V.; Plotnikov, V. A.; Lysikov, M. V.

2017-12-01

Stepwise kinetics of deformation accumulation and monotonous and pulsed acoustic emission bear witness to the active role of acoustic emission in deformation processes. A standing acoustic wave in the region of deformation localization determines the effect of self-organization of dislocations on macroscopic scales around the natural resonator of the system.

A moisture and electric coupling stimulated ionic polymer-metal composite actuator with controllable deformation behavior

NASA Astrophysics Data System (ADS)

Ru, Jie; Zhu, Zicai; Wang, Yanjie; Chen, Hualing; Bian, Changsheng; Luo, Bin; Li, Dichen

2018-02-01

Ionic polymer-metal composite (IPMC) actuator can generate large and rapid deformation based on ion migration under a relatively low driving voltage. Under full hydrated conditions, the deformation is always prone to relaxation. At room humidity conditions, the deformation increases substantially at the early stage of actuation, and then decreases gradually. Generally, most researchers considered that the change of water content or relative humidity mainly leads to the deformation instabilities, which severely limits the practical applications of IPMC. In this Letter, a novel actuation mode is proposed to control the deformation behavior of IPMC by employing moisture as an independent or collaborative incentive source together with the electric field. The deformation response is continuously measured under electric field, electric field-moisture coupling stimulus and moisture stimulus. The result shows that moisture can be a favorable driving factor for IPMC actuation. Such an electric field-moisture coupling stimulus can avoid the occurrence of deformation instabilities and guarantee a superior controllable deformation in IPMC actuation. This research provides a new method to obtain stable and large deformation of IPMC, which is of great significance for the guidance of material design and application for IPMC and IPMC-type iEAP materials.

Longitudinal changes in ventral and dorsal neck muscle layers during loading against gravity in healthy volunteers using speckle tracking.

PubMed

Peolsson, Anneli; Peolsson, Michael

2014-05-01

This study aimed to describe and compare the longitudinal mechanical activity, deformation, and deformation rate of the different layers of dorsal and ventral neck muscles in healthy volunteers during head lifts against gravity. The cross-sectional study included 19 healthy volunteers (mean age, 28 years; SD, 7 years). Ultrasound with speckle-tracking analysis was used to investigate longitudinal mechanical activation, deformation, and deformation rate of dorsal and ventral neck muscles in real time during a head lift. Significance levels were set as P = .025 or P = .0125, depending on the number of comparisons. The dorsal neck muscles did not significantly differ in deformation (P > .04); however, the multifidus had a higher deformation rate than all other dorsal muscles (P < .003). The sternocleidomastoid had significantly higher deformation than the longus capitis (P = .005) and colli (P = .001) but a lower deformation rate than the longus colli (P = .02). The sternocleidomastoid deformed more than the deeper muscles, but it did significantly slower than the longus colli. Among the dorsal muscles, the deepest (the multifidus) had the highest deformation rate. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Deformation-induced crystallographic-preferred orientation of hcp-iron: An experimental study using a deformation-DIA apparatus

NASA Astrophysics Data System (ADS)

Nishihara, Yu; Ohuchi, Tomohiro; Kawazoe, Takaaki; Seto, Yusuke; Maruyama, Genta; Higo, Yuji; Funakoshi, Ken-ichi; Tange, Yoshinori; Irifune, Tetsuo

2018-05-01

Shear and uniaxial deformation experiments on hexagonal close-packed iron (hcp-Fe) was conducted using a deformation-DIA apparatus at a pressure of 13-17 GPa and a temperature of 723 K to determine its deformation-induced crystallographic-preferred orientation (CPO). Development of the CPO in the deforming sample is determined in-situ based on two-dimensional X-ray diffraction using monochromatic synchrotron X-rays. In the shear deformation geometry, the <0001> and < 11 2 bar 0 > axes gradually align to be sub-parallel to the shear plane normal and shear direction, respectively, from the initial random texture. In the uniaxial compression and tensile geometry, the <0001> and < 11 2 bar 0 > axes, respectively, gradually align along the direction of the uniaxial deformation axis. These results suggest that basal slip (0001) < 11 2 bar 0 > is the dominant slip system in hcp-Fe under the studied deformation conditions. The P-wave anisotropy for a shear deformed sample was calculated using elastic constants at the inner core condition by recent ab-initio calculations. Strength of the calculated anisotropy was comparable to or higher than axisymmetric anisotropy in Earth's inner core.

Microstructure characterization based on the type of deformed grains in cold-rolled, Cu-added, bake-hardenable steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, J.S.; Kim, S.I.; Choi, S.-H., E-mail: shihoon@sunchon.ac.kr

2014-06-01

The electron backscatter diffraction technique has been used to characterize the microstructure of deformed grains in cold-rolled, Cu-added, bake-hardenable steel. A new scheme based on the kind and number of average orientations, as determined from a unique grain map of the deformed grains, was developed in order to classify deformed grains by type. The α-fiber components, γ-fiber components and random orientations, those which could not be assigned to either γ-fiber or α-fiber components, were used to define the average orientation of unique grains within individual deformed grains. The microstructures of deformed grains in as-rolled specimens were analyzed based on themore » Taylor factor, stored energy, and misorientation. The relative levels and distributions of the Taylor factor, the stored energy and the misorientation were examined in terms of the types of deformed grains. - Highlights: • We characterized the microstructure of Cu-added BH steel using EBSD. • A new scheme was developed in order to classify deformed grains by type. • Stored energy and misorientation are strongly dependent on the type of deformed grains. • Microstructure was examined in terms of the types of deformed grains.« less

Effect of deformation ratios on grain alignment and magnetic properties of hot pressing/hot deformation Nd-Fe-B magnets

NASA Astrophysics Data System (ADS)

Guo, Zhaohui; Li, Mengyu; Wang, Junming; Jing, Zheng; Yue, Ming; Zhu, Minggang; Li, Wei

2018-05-01

The magnetic properties, microstructure and orientation degrees of hot pressing magnet and hot deformation Nd-Fe-B magnets with different deformation ratios have been investigated in this paper. The remanence (Br) and maximum magnetic energy product ((BH)max) were enhanced gradually with the deformation ratio increasing from 0% to 70%, whereas the coercivity (HCj) decreased. The scanning electron microscopy (SEM) images of fractured surfaces parallel to the pressure direction during hot deformation show that the grains tend to extend perpendicularly to the c-axes of Nd2Fe14B grains under the pressure, and the aspect ratios of the grains increase with the increase of deformation ratio. Besides, the compression stress induces the long axis of grains to rotate and the angle (θ) between c-axis and pressure direction decreases. The X-ray diffraction (XRD) patterns reveal that orientation degree improves with the increase of deformation ratio, agreeing well with the SEM results. The hot deformation magnet with a deformation ratio of 70% has the best Br and (BH)max, and the magnetic properties are as followed: Br=1.40 T, HCj=10.73 kOe, (BH)max=42.30 MGOe.

Deformation twinning: Influence of strain rate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, G.T. III

Twins in most crystal structures, including advanced materials such as intermetallics, form more readily as the temperature of deformation is decreased or the rate of deformation is increased. Both parameters lead to the suppression of thermally-activated dislocation processes which can result in stresses high enough to nucleate and grow deformation twins. Under high-strain rate or shock-loading/impact conditions deformation twinning is observed to be promoted even in high stacking fault energy FCC metals and alloys, composites, and ordered intermetallics which normally do not readily deform via twinning. Under such conditions and in particular under the extreme loading rates typical of shockmore » wave deformation the competition between slip and deformation twinning can be examined in detail. In this paper, examples of deformation twinning in the intermetallics TiAl, Ti-48Al-lV and Ni{sub 3}A as well in the cermet Al-B{sub 4}C as a function of strain rate will be presented. Discussion includes: (1) the microstructural and experimental variables influencing twin formation in these systems and twinning topics related to high-strain-rate loading, (2) the high velocity of twin formation, and (3) the influence of deformation twinning on the constitutive response of advanced materials.« less

Populações estelares do bojo galáctico

NASA Astrophysics Data System (ADS)

Escudero, A. V.; Costa, R. D. D.; Maciel, W. J.

2003-08-01

Os estudos mais recentes do bojo galáctico têm enfocado essencialmente as abundâncias químicas de elementos pesados, como o ferro, obtidos a partir das estrelas nas regiões centrais da galáxia. Elementos leves, como hélio, nitrogênio, oxigênio e argônio ainda são pouco estudados nestas regiões, devido à difícil determinação de suas abundâncias a partir de estrelas. Nestas condições as nebulosas planetárias desempenham um importante papel, pois permitem a determinação de abundâncias destes elementos usando técnicas de espectroscopia nebular. Neste trabalho, reportamos a análise das abundâncias químicas de uma nova amostra de nebulosas planetárias do bojo, bem como os resultados preliminares de um código numérico destinado a modelar a evolução química desta região. Usamos como vínculos observacionais os resultados obtidos das nebulosas planetárias, bem como de abundâncias estelares da região do bojo, obtidas da literatura. A partir deste modelo da evolução química e dos vínculos observacionais foi possível fazer um diagnóstico mais preciso das populações que constituem o bojo galáctico. O estudo destas populações que compõem a região central de nossa galáxia é de extrema importância para o maior entendimento da evolução química e dinâmica da galáxia como um todo. Por isto, verificamos a importância dos modelos de formação simples e mista utilizados para explicar características da população da região central da galáxia. Algumas destas características são: uma grande dispersão nos valores das abundâncias químicas e um grande espalhamento nas correlações entre as abundâcias de nitrogênio e oxigênio. Estas peculiaridades são dificilmente reproduzidas por modelos de formação simples, e portanto são importantes indícios da validade dos modelos de formação mista, tais como um rápido colapso do bojo seguido de uma evolução secular. (FAPESP, CNPq)

On the distinction between large deformation and large distortion for anisotropic materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

BRANNON,REBECCA M.

2000-02-24

A motion involves large distortion if the ratios of principal stretches differ significantly from unity. A motion involves large deformation if the deformation gradient tensor is significantly different from the identity. Unfortunately, rigid rotation fits the definition of large deformation, and models that claim to be valid for large deformation are often inadequate for large distortion. An exact solution for the stress in an idealized fiber-reinforced composite is used to show that conventional large deformation representations for transverse isotropy give errant results. Possible alternative approaches are discussed.

[What was found in deformities of leprosy patients from the view-point of orthopedics?].

PubMed

Obara, Akiko

2003-08-01

No more deformities which are the cause of social stigma by early detection and chemotherapy! Let patients learn how to avoid getting deformed to keep normal ADL & QOL. Fight against the nerve damage and stop the progressive deformities by organizing the team approach. Instead of intense efforts of taking care by well organized team work, deformities are resulted inevitably in some cases. Let their deformities be out of the way of their keeping normal community lives without any prejudice, respecting their human rights and dignity.

Autonomous Formation Flying from Ground to Flight

NASA Technical Reports Server (NTRS)

Chapman, Keith B.; Dell, Gregory T.; Rosenberg, Duane L.; Bristow, John

1999-01-01

The cost of on-orbit operations remains a significant and increasingly visible concern in the support of satellite missions. Headway has been made in automating some ground operations; however, increased mission complexity and more precise orbital constraints have compelled continuing human involvement in mission design and maneuver planning operations. AI Solutions, Inc. in cooperation with the National Aeronautics and Space Administration's (NASA) Goddard Space Flight Center (GSFC) has tackled these more complex problems through the development of AutoCon as a tool for an automated solution. NASA is using AutoCon to automate the maneuver planning for the Earth Orbiter-1 (EO-1) mission. AutoCon was developed originally as a ground system tool. The EO-1 mission will be using a scaled version of AutoCon on-board the EO-1 satellite to command orbit adjustment maneuvers. The flight version of AutoCon plans maneuvers based on formation flying algorithms developed by GSFC, JPL, and other industry partners. In its fully autonomous mode, an AutoCon planned maneuver will be executed on-board the satellite without intervention from the ground. This paper describes how AutoCon automates maneuver planning for the formation flying constraints of the EO-1 mission. AutoCon was modified in a number of ways to automate the maneuver planning on-board the satellite. This paper describes how the interface and functionality of AutoCon were modified to support the on-board system. A significant component of this modification was the implementation of a data smoother, based on a Kalman filter, that ensures that the spacecraft states estimated by an on-board GPS receiver are as accurate as possible for maneuver planning. This paper also presents the methodology use to scale the AutoCon functionality to fit and execute on the flight hardware. This paper also presents the modes built that allow the incremental phasing in of autonomy. New technologies for autonomous operations are usually received with significant, and probably appropriate trepidation. A number of safeguards have been designed in both AutoCon and the interfacing systems to alleviate the potential of mission-impacting anomalies from the on-board autonomous system. This paper describes the error checking, input data integrity validation and limits set on maneuvers in AutoCon and the on-board system.

Autonomous Formation Flying from the Ground to Flight

NASA Technical Reports Server (NTRS)

Chapman, Keith B.; Dell, Gregory T.; Rosenberg, Duane L.; Bristow, John

1999-01-01

The cost of on-orbit operations remains a significant and increasingly visible concern in the support of satellite missions. Headway has been made in automating some ground operations; however, increased mission complexity and more precise orbital constraints have compelled continuing human involvement in mission design and maneuver planning operations. AI Solutions, Inc. in cooperation with the National Aeronautics and Space Administration's (NASA) Goddard Space Flight Center (GSFC) has tackled these more complex problems through the development of AutoCon(TM) as a tool for an automated solution. NASA is using AutoCon(TM) to automate the maneuver planning for the Earth Orbiter-1 (EO-1) mission. AutoCon(TM) was developed originally as a ground system tool. The EO-1 mission will be using a scaled version of AutoCon(TM) on-board the EO-1 satellite to command orbit adjustment maneuvers. The flight version of AutoCon(TM) plans maneuvers based on formation flying algorithms developed by GSFC, JPL, and other industry partners. In its fully autonomous mode, an AutoCon(TM) planned maneuver will be executed on-board the satellite without intervention from the ground. This paper describes how AutoCon(TM) automates maneuver planning for the formation flying constraints of the EO-1 mission. AutoCon(TM) was modified in a number of ways to automate the maneuver planning on-board the satellite. This paper describes how the interface and functionality of AutoCon(TM) were modified to support the on-board system. A significant component of this modification was the implementation of a data smoother, based on a Kalman filter, that ensures that the spacecraft states estimated by an on-board GPS receiver are as accurate as possible for maneuver planning. This paper also presents the methodology used to scale the AutoCon(TM) functionality to fit and execute on the flight hardware. This paper also presents the modes built into the system that allow the incremental phasing in of autonomy. New technologies for autonomous operations are usually received with significant, and probably appropriate, trepidation. A number of safeguards have been designed in both AutoCon(TM) and the interfacing systems to alleviate the potential of mission-impacting anomalies from the on-board autonomous system. This paper describes the error checking, input data integrity validation, and limits set on maneuvers in AutoCon(TM) and the on-board system.

Comparison of Immunogenicity in Rhesus Macaques of Transmitted-Founder, HIV-1 Group M Consensus, and Trivalent Mosaic Envelope Vaccines Formulated as a DNA Prime, NYVAC, and Envelope Protein Boost

PubMed Central

Hulot, Sandrine L.; Korber, Bette; Giorgi, Elena E.; Vandergrift, Nathan; Saunders, Kevin O.; Balachandran, Harikrishnan; Mach, Linh V.; Lifton, Michelle A.; Pantaleo, Giuseppe; Tartaglia, Jim; Phogat, Sanjay; Jacobs, Bertram; Kibler, Karen; Perdiguero, Beatriz; Gomez, Carmen E.; Esteban, Mariano; Rosati, Margherita; Felber, Barbara K.; Pavlakis, George N.; Parks, Robert; Lloyd, Krissey; Sutherland, Laura; Scearce, Richard; Letvin, Norman L.; Seaman, Michael S.; Alam, S. Munir; Montefiori, David; Liao, Hua-Xin; Haynes, Barton F.

2015-01-01

ABSTRACT An effective human immunodeficiency virus type 1 (HIV-1) vaccine must induce protective antibody responses, as well as CD4+ and CD8+ T cell responses, that can be effective despite extraordinary diversity of HIV-1. The consensus and mosaic immunogens are complete but artificial proteins, computationally designed to elicit immune responses with improved cross-reactive breadth, to attempt to overcome the challenge of global HIV diversity. In this study, we have compared the immunogenicity of a transmitted-founder (T/F) B clade Env (B.1059), a global group M consensus Env (Con-S), and a global trivalent mosaic Env protein in rhesus macaques. These antigens were delivered using a DNA prime-recombinant NYVAC (rNYVAC) vector and Env protein boost vaccination strategy. While Con-S Env was a single sequence, mosaic immunogens were a set of three Envs optimized to include the most common forms of potential T cell epitopes. Both Con-S and mosaic sequences retained common amino acids encompassed by both antibody and T cell epitopes and were central to globally circulating strains. Mosaics and Con-S Envs expressed as full-length proteins bound well to a number of neutralizing antibodies with discontinuous epitopes. Also, both consensus and mosaic immunogens induced significantly higher gamma interferon (IFN-γ) enzyme-linked immunosorbent spot assay (ELISpot) responses than B.1059 immunogen. Immunization with these proteins, particularly Con-S, also induced significantly higher neutralizing antibodies to viruses than B.1059 Env, primarily to tier 1 viruses. Both Con-S and mosaics stimulated more potent CD8-T cell responses against heterologous Envs than did B.1059. Both antibody and cellular data from this study strengthen the concept of using in silico-designed centralized immunogens for global HIV-1 vaccine development strategies. IMPORTANCE There is an increasing appreciation for the importance of vaccine-induced anti-Env antibody responses for preventing HIV-1 acquisition. This nonhuman primate study demonstrates that in silico-designed global HIV-1 immunogens, designed for a human clinical trial, are capable of eliciting not only T lymphocyte responses but also potent anti-Env antibody responses. PMID:25855741

FEM modeling of postseismic deformation of poroelastic material

NASA Astrophysics Data System (ADS)

Kawamoto, S.; Ito, T.; Hirahara, K.

2004-12-01

Following a large earthquake, postseismic deformation in the focal region has been observed by GPS, leveling measurements and the other geodetic measurements. To explain the postseismic deformation, researchers have proposed and well investigated two physical mechanisms of afterslip and viscoelastic relaxation. In some cases, however, there have been observed postseismic deformation which can not be explained by these mechanisms. Therefore, another mechanism has been proposed, where the crust is treated as "poroelastic material". This concept is called "poroelasticity". In this concept, postseismic deformation is caused by pore fluid flow due to the coseismic stress redistribution. We explored, therefore, the postseismic deformation due to pore fluid flow in a poroelastic material using finite element method (FEM), which can easily handle lateral variations of hydraulic diffusivity and elastic or plastic property. We used the FEM program 'CAMBIOT3D' originally developed by Geotech. Lab. Gunma University, Japan (2003). Because this program was developed for soil mechanics, we must have modified so as to calculate deformation due to earthquake faulting. We implemented the 'split node technique' (Melosh and Refsky, 1981) to calculate the coseismic deformation. In addition to this, we modified the program to calculate the deformation taking into account the Skempton's B. This coefficient B determines what fraction of the coseismic stress due to an earthquake is allotted to pore pressure. Without Skempton's B, coseismic pore pressure becomes too large and hence postseismic deformation is calculated too large. We evaluated the postseismic deformation in a poroelastic material to show that the poroelastic deformation is quite different from that of afterslip and viscoelastic relaxation models. In this presentation, we show the postseismic deformation due to pore fluids flow in a poroelastic material and the effect of Skempton's B. Especially, we discuss what different pattern of postseismic deformation is produced depending on the lateral variation of hydraulic diffusivity structures in and around the fault zone, which structures have been differently inferred from fault zone core sampling researches and so on.

Monitoring of Deformation in Ground Before and After Tunnel Excavation

NASA Astrophysics Data System (ADS)

Eren, Mehmet; Hilmi Erkoç, Muharrem

2017-04-01

As population increase in metropolitan city, we need transportation and transmission tunnel. In this context, the engineers and administors attach impotance to building and planning underground-tunnel. Moreover, we must at regular intervals monitoring to deformation in underground-tunnel for quality and safety. Firstly, a deformation monitoring network is designed as perpendicular to the tunnel main axis. Secondly, the prescribed number of deformation measurements must be made. Finally, the deformation analysis is evaluated and its results is interpreted. This study investigates how deformation in monitoring network during and after tunnel excavate change.For this purpose, a deformation monitoring network of 18 object point and 4 reference point was established. Object points networks was designed steeply to the tunnel main axis as 3 cross section. Each cross section consisted of 3 point left, 2 point right and 1 point at the flowing line. Initial conditional measurement was made before tunnel excavation. Then the deformation measurement was made 5 period (1 period measured after tunnel excavate). All data sets were adjusted according to free adjustment method. The results from the investigation considering the tunnel line, a symmetrical subsidence was observed. The following day of tunnel excavation, we were observed %68 per of the total deformation. At the end of the last period measurements, %99 per of the total deformation was detected. Keywords: Tunnel, Deformation, Subsidence, Excavation

Variabilidad de la Estación de Crecimiento en la Región Sur de Tamaulipas en condiciones climaticas actuales y futuras.

NASA Astrophysics Data System (ADS)

Medina-Barrios, M.; Conde-Alvarez, C.; Gay-Garcia, C.

2007-05-01

El impacto de la variabilidad y cambio climáticos, afectan el potencial agrícola de la Región Sur de Tamaulipas. Además de los cambios estacionales, bajos rendimientos agrícolas, el manejo de los cultivos y las políticas locales de producción, existe la incertidumbre del mercado regional para los pequeños y grandes productores. La diversificación agrícola ha sido una alternativa para enfrentar las condiciones imperantes en esta región. Pero ésta ha provocado la fragmentación territorial, por lo que sólo algunos productores logran competir en un mercado nacional. Existe una preocupación generalizada por buscar soluciones que permitan que la población que es afectada por la inseguridad de la producción agrícola y económica, pueda adaptarse a las variaciones climáticas que afectan el proceso productivo. La seguridad alimentaría queda sujeta a la fluctuación de las importaciones para los sectores básicos y a las estrategias mercantiles de empresas trasnacionales. La percepción local sugiere un número creciente de eventos climatológicos extremos, constantes y severos en los últimos 20 años, con el aumento creciente de pérdidas económicas. El análisis se centra en la disponibilidad de agua, agregándose un aspecto de capital importancia como es la variabilidad interanual de la lluvia, que condiciona muy fuertemente el riesgo agrícola en el trópico seco, siendo ésta la que determina el momento de inicio de la estación favorable para el crecimiento y su duración. En este trabajo se han obtenido modelos de la distribución espacial de la precipitación y temperaturas, para el escenario base 1961-1990, el escenario actual 1971-2000, para algunos años El Niño y La Niña, así como para los escenarios de Cambio Climático HADLEY, ECHAM y GFDL, con escenarios A2 y B2, para las décadas de los 20s y 50s, para establecer el inicio y duración de la Estación de Crecimiento, utilizando Sistemas de Información Geográfica (ArcView). Estos resultados serán utilizados por los administradores de las decisiones locales, para estrategias de manejo y para la difusión entre los habitantes, de tal manera que esto les permita establecer prioridades en las medidas de mitigación, y formular las posibilidades de adaptación.

Poblacion estelar joven embebida en la nube molecular galactica asociada a la fuente IRAS 18236-1205

NASA Astrophysics Data System (ADS)

Romero, Ricardo Retes

2008-06-01

En esta tesis presento una metodología de seleccion y estudio de la población estelar embebida en la nube molecular galactica asociada a la fuente IRAS 18236-1205. La fuente IRAS posee colores de region Ultra Compacta HII (UCHII) y tiene deteccióon en monosulfuro de carbono (CS), trazador molecular de alta densidad, lo cual da la posibilidad de definir la nube molecular asociada hacia esta region. Lo anterior muestra que esta es buena candidata a región de formación estelar masiva. La metodología de seleccion de la población embebida, est à basada por una parte, en la distribución del gas molecular monoxido de carbono (13CO) asociado a la fuente IRAS, nube molecular seleccionada del mapeo Galactic Ring Survey (GRS) realizado en 13CO. Otros pasos de la seleccion, se basan en los diagramas color-color y color-magnitud con datos del cercano infrarrrojo de 2MASS. Para el estudio de la componente estelar se usaron los catalogos de fuentes puntuales en el cercano, medio y lejano infrarrojo de 2MASS, SPITZER e IRAS, respectivamente. De los diagramas color-color y color-magnitud, usando datos de 2MASS, se construyo un criterio fotométrico para identificar los objetos estelares j ovenes embebidos en la region molecular. Aplicando modelos a la distribución espectral de energía (SED) de algunos ellos, se encontraron parametros estelares de objetos estelares j ovenes embebidos de masa intermedia y alta. Adicionalmente, se encontro un objeto de masa ´ intermedia no identifiado por el catalogo de 2MASS y su efecto sobre el medio interestelar, emision en la banda de [4.5] μm de IRAC-Spitzer asociado a un outflow. Dos de los objetos seleccionados por el criterio fotometrico resultaron ser objetos estelares jovenes de alta e intermedia masa (B1V/B2V y B8V/A0V respectivamente), los cuales deben estar asociados a la emision radiativa responsable de los colores de región UC HII. Otro objeto estelar joven de baja masa (F0V/F5V) fue encontrado en la region de estudio. Este parece estar asociado con la presencia de un disco circumestelar y material excitado por choque (IRAC-Spitzer [4.5]μm). Se concluye que el escenario de region de formación estelar masiva factible para esta region molecular es el de una asociación estelar joven embebida en una densa región molecular (AV . 30) hacia la fuente IRAS 18236-1205.

Creep of high-strength normal and lightweight concrete.

DOT National Transportation Integrated Search

2004-01-01

In addition to immediate elastic deformations, concrete undergoes time-dependent deformations that must be considered in design. Creep is defined as the time-dependent deformation resulting from a sustained stress. Shrinkage deformation is the time-d...

Cosmetic and Functional Nasal Deformities

MedlinePlus

... nasal complaints. Nasal deformity can be categorized as “cosmetic” or “functional.” Cosmetic deformity of the nose results in a less ... taste , nose bleeds and/or recurrent sinusitis . A cosmetic or functional nasal deformity may occur secondary to ...

Effects of torsional deformation on the microstructures and mechanical properties of a CoCrFeNiMo0.15 high-entropy alloy

NASA Astrophysics Data System (ADS)

Wu, Wenqian; Guo, Lin; Liu, Bin; Ni, Song; Liu, Yong; Song, Min

2017-12-01

The effects of torsional deformation on the microstructures and mechanical properties of a CoCrFeNiMo0.15 high-entropy alloy have been investigated. The torsional deformation generates a gradient microstructure distribution due to the gradient torsional strain. Both dislocation activity and deformation twinning dominated the torsional deformation process. With increasing the torsional equivalent strain, the microstructural evolution can be described as follows: (1) formation of pile-up dislocations parallel to the trace of {1 1 1}-type slip planes; (2) formation of Taylor lattices; (3) formation of highly dense dislocation walls; (3) formation of microbands and deformation twins. The extremely high deformation strain (strained to fracture) results in the activation of wavy slip. The tensile strength is very sensitive to the torsional deformation, and increases significantly with increasing the torsional angle.

Analyses of Deformation and Stress of Oil-free Scroll Compressor Scroll

NASA Astrophysics Data System (ADS)

Peng, Bin; Li, Yaohong; Zhao, Shenxian

2017-12-01

The solid model of orbiting and fixed scroll is created by the Solidworks The deformation and stress of scrolls under gas force, temperature field, inertia force and the coupling field are analyzed using the Ansys software. The deformation for different thickness and height scroll tooth is investigated. The laws of deformation and stress for scrolls are gotten. The research results indicate that the stress and deformation of orbiting scroll are mainly affected by the temperature field. The maximum deformation occurs in the tooth head of scroll wrap because of the largest gas forces and the highest temperature in the tooth head of scroll wrap. The maximum stress is located in the end of the tooth, and the maximum stress of the coupling field is not the sum of loads. The scroll tooth is higher, and the deformation is bigger. The scroll tooth is thicker, and the deformation is smaller.

Sensing surface mechanical deformation using active probes driven by motor proteins

PubMed Central

Inoue, Daisuke; Nitta, Takahiro; Kabir, Arif Md. Rashedul; Sada, Kazuki; Gong, Jian Ping; Konagaya, Akihiko; Kakugo, Akira

2016-01-01

Studying mechanical deformation at the surface of soft materials has been challenging due to the difficulty in separating surface deformation from the bulk elasticity of the materials. Here, we introduce a new approach for studying the surface mechanical deformation of a soft material by utilizing a large number of self-propelled microprobes driven by motor proteins on the surface of the material. Information about the surface mechanical deformation of the soft material is obtained through changes in mobility of the microprobes wandering across the surface of the soft material. The active microprobes respond to mechanical deformation of the surface and readily change their velocity and direction depending on the extent and mode of surface deformation. This highly parallel and reliable method of sensing mechanical deformation at the surface of soft materials is expected to find applications that explore surface mechanics of soft materials and consequently would greatly benefit the surface science. PMID:27694937

Formation of incoherent deformation twin boundaries in a coarse-grained Al-7Mg alloy

NASA Astrophysics Data System (ADS)

Jin, S. B.; Zhang, K.; Bjørge, R.; Tao, N. R.; Marthinsen, K.; Lu, K.; Li, Y. J.

2015-08-01

Deformation twinning has rarely been observed in coarse grained Al and its alloys except under some extreme conditions such as ultrahigh deformation strain or strain rates. Here, we report that a significant amount of Σ3 deformation twins could be generated in a coarse-grained Al-7 Mg alloy by dynamic plastic deformation (DPD). A systematic investigation of the Σ3 boundaries shows that they are Σ3{112} type incoherent twin boundaries (ITBs). These ITBs have formed by gradual evolution from copious low-angle deformation bands through <111>-twist Σ boundaries by lattice rotation. These findings provide an approach to generate deformation twin boundaries in high stacking fault energy metallic alloys. It is suggested that high solution content of Mg in the alloy and the special deformation mode of DPD played an important role in formation of the Σ and ITBs.

Initiation of deformation of the Eastern California Shear Zone: Constraints from Garlock fault geometry and GPS observations

USGS Publications Warehouse

Gan, Weijun; Zhang, P.; Shen, Z.-K.; Prescott, W.H.; Svarc, J.L.

2003-01-01

We suggest a 2-stage deformation model for the Eastern California Shear Zone (ECSZ) to explain the geometry of the Garlock fault trace. We assume the Garlock fault was originally straight and then was gradually curved by right-lateral shear deformation across the ECSZ. In our 2-stage deformation model, the first stage involves uniform shear deformation across the eastern part of the shear zone, and the second stage involves uniform shear deformation across the entire shear zone. In addition to the current shape of the Garlock fault, our model incorporates constraints on contemporary deformation rates provided by GPS observations. We find that the best fitting age for initiation of shear in eastern part of the ECSZ is about 5.0 ?? 0.4 Ma, and that deformation of the western part started about 1.6 Myr later.

Pollybeak Deformity in Middle Eastern Rhinoplasty: Prevention and Treatment.

PubMed

Hussein, Wael K A; Foda, Hossam M T

2016-08-01

The pollybeak deformity is one of the commonest causes of revision rhinoplasty. The Middle Eastern nose has certain criteria that predispose to the development of pollybeak deformity. The aim of this study is to detect the factors contributing to the development of pollybeak deformity in the Middle Eastern nose and methods used to prevent as well as to treat such deformity. Out of the 1,160 revision patients included in this study, 720 (62%) patients had a pollybeak deformity. The commonest contributing factors included underprojected tip with poor support in 490 (68%) patients, excessive supratip scarring in 259 (36%) patients, overresected bony dorsum in 202 (28%) patients, and high anterior septal angle in 173 (24%) patients. The methods used by the authors to treat the pollybeak deformity are described, along with the local steroid injection protocol used to guard against the recurrence of pollybeak deformity. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Differential calculus and gauge transformations on a deformed space

NASA Astrophysics Data System (ADS)

Wess, Julius

2007-08-01

We consider a formalism by which gauge theories can be constructed on noncommutative space time structures. The coordinates are supposed to form an algebra, restricted by certain requirements that allow us to realise the algebra in terms of star products. In this formulation it is useful to define derivatives and to extend the algebra of coordinates by these derivatives. The elements of this extended algebra are deformed differential operators. We then show that there is a morphism between these deformed differential operators and the usual higher order differential operators acting on functions of commuting coordinates. In this way we obtain deformed gauge transformations and a deformed version of the algebra of diffeomorphisms. The deformation of these algebras can be clearly seen in the category of Hopf algebras. The comultiplication will be twisted. These twisted algebras can be realised on noncommutative spaces and allow the construction of deformed gauge theories and deformed gravity theory.

Loading Deformation Characteristic Simulation Study of Engineering Vehicle Refurbished Tire

NASA Astrophysics Data System (ADS)

Qiang, Wang; Xiaojie, Qi; Zhao, Yang; Yunlong, Wang; Guotian, Wang; Degang, Lv

2018-05-01

The paper constructed engineering vehicle refurbished tire computer geometry model, mechanics model, contact model, finite element analysis model, did simulation study on load-deformation property of engineering vehicle refurbished tire by comparing with that of the new and the same type tire, got load-deformation of engineering vehicle refurbished tire under the working condition of static state and ground contact. The analysis result shows that change rules of radial-direction deformation and side-direction deformation of engineering vehicle refurbished tire are close to that of the new tire, radial-direction and side-direction deformation value is a little less than that of the new tire. When air inflation pressure was certain, radial-direction deformation linear rule of engineer vehicle refurbished tire would increase with load adding, however, side-direction deformation showed linear change rule, when air inflation pressure was low; and it would show increase of non-linear change rule, when air inflation pressure was very high.

The Procurement of Non Developmental Items: Pros and Cons

DTIC Science & Technology

1994-09-01

commercial way of procurement will bring more advantages than disadvantages to DOD. The list of the pros greatly outweighs the cons . There is practically...AD-A285 009 MH PROCUREMENT OF NON DEVELOPMENTAL ITEMS: PROS AND CONS THES IS Giorgio Scappaticci. Lt. Col., Italian Air Force AFIT/GLMILALj94S-3 I...PROS AND CONS U;narmou,.ced 0 Justification THESIS Giorgio Scappaticci, Lt. Col., Italian Air Force Dist’ibution f Availability Codes AFIT/GLM/LAL

Status of Major Acquisitions As of September 30, 1981: Better Reporting Essential to Controlling Cost Growth

DTIC Science & Technology

1982-04-22

acquisition would be an obligation made by the Environmental Protection Agency to a State to aid in the construction of a sewage treatment plant ...DE 1 PINELLAS COUNTY-TREASURE IS. CON FT... 3 FIRE IS. INLET TO JONES BEACH CON NY 2 TOTAL ESTIMATED COST CURRENT BASELINE...HELLFIRE MISSILE SYSTEM EQP OH 418 :I:ND WASTE TREATMENT PLANT CON TN 345 HOSPITAL IMPROVEMENTS FT HOOD CON TX 339 MLRS

Inhibition of the mobility of mouse lymphocyte surface immunoglobulins by locally bound concanavalin A.

PubMed Central

Henis, Y I; Elson, E L

1981-01-01

Fluorescence photobleaching recovery was used to study directly and quantitatively the inhibition of the lateral mobility of surface immunoglobulins (sIg) on mouse lymphocytes by localized binding of concanavalin A (Con A) coupled to platelets. Up to a threshold occupancy of about 10% of the upper cell surface by Con A-platelets, the diffusion coefficient and mobile fraction of sIg remained as in untreated cells (5.3 X 10(-10) cm2/sec and 0.65, respectively). At higher surface occupancy, these values decreased to 8 X 10(-11) cm2/sec and 0.11. The magnitude of the effect was independent of the percentage occupancy above the threshold and of the distance from the bound Con A-platelets, indicating a cooperative and propagated phenomenon. Treatment with colchicine or cytochalasin B separately induced only partial reversal of the Con A-induced modulation. Treatment with both reversal of the Con A-induced modulation. Treatment with both drugs together was synergistic and fully reversed the mobility inhibition. The modulation was unaffected by NaN3 and 2-deoxyglucose, suggesting no dependence on metabolic energy. Con A-platelets did not affect the mobility of a lipid probe. Models for the Con A-induced modulation and the relationship between the effects of Con A on sIg mobility and patch formation are discussed. PMID:6940124

Pretreatment with propylene glycol alginate sodium sulfate ameliorated concanavalin A-induced liver injury by regulating the PI3K/Akt pathway in mice.

PubMed

Xu, Shizan; Wu, Liwei; Zhang, Qinghui; Feng, Jiao; Li, Sainan; Li, Jingjing; Liu, Tong; Mo, Wenhui; Wang, Wenwen; Lu, Xiya; Yu, Qiang; Chen, Kan; Xia, Yujing; Lu, Jie; Xu, Ling; Zhou, Yingqun; Fan, Xiaoming; Guo, Chuanyong

2017-09-15

Propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide possesses anti-inflammatory effects. Here, we investigated the effect of PSS on concanavalin A (Con A)-induced liver injury in mice and examined the underlying mechanisms. Balb/C mice were injected intravenously with Con A (25mg/kg) to generate a model of acute liver injury. PSS (25 or 50mg/kg) was injected intraperitoneally 1h before the Con A administration. The levels of serum liver enzymes, inflammatory cytokines, and other marker proteins were determined, and liver injury was assessed histopathologically 2, 8, and 24h after Con A injection. Pretreatment with PSS reduced the levels of serum liver enzymes, inflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, and attenuated histopathological damage in Con A-induced liver injury in mice. The effects of Con A were mediated by apoptosis and autophagy, as indicated by changes in protein and gene expression of related factors after Con A injection. PSS activated the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway and showed a protective function against apoptosis and autophagy. PSS ameliorated Con A-induced liver injury by downregulating inflammatory cytokines including TNF-α and IL-1β and regulating apoptosis and autophagy via the PI3K/Akt pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

Anabaena sp. strain PCC 7120 conR contains a LytR-CpsA-Psr domain, is developmentally regulated, and is essential for diazotrophic growth and heterocyst morphogenesis.

PubMed

Mella-Herrera, Rodrigo A; Neunuebel, M Ramona; Golden, James W

2011-03-01

The conR (all0187) gene of the filamentous cyanobacterium Anabaena (Nostoc) sp. strain PCC 7120 is predicted to be part of a family of proteins that contain the LytR-CpsA-Psr domain associated with septum formation and cell wall maintenance. The conR gene was originally misannotated as a transcription regulator. Northern RNA blot analysis showed that conR expression was upregulated 8 h after nitrogen step-down. Fluorescence microscopy of a P(conR)-gfp reporter strain revealed increased GFP fluorescence in proheterocysts and heterocysts beginning 9 h after nitrogen step-down. Insertional inactivation of conR caused a septum-formation defect of vegetative cells grown in nitrate-containing medium. In nitrate-free medium, mutant filaments formed abnormally long heterocysts and were defective for diazotrophic growth. Septum formation between heterocysts and adjacent vegetative cells was abnormal, often with one or both poles of the heterocysts appearing partially open. In a conR mutant, expression of nifH was delayed after nitrogen step-down and nitrogenase activity was approximately 70 % of wild-type activity, indicating that heterocysts of the conR mutant strain are partially functional. We hypothesize that the diazotrophic growth defect is caused by an inability of the heterocysts to transport fixed nitrogen to the neighbouring vegetative cells.

Salidroside mediates apoptosis and autophagy inhibition in concanavalin A-induced liver injury

PubMed Central

Feng, Jiao; Niu, Peiqin; Chen, Kan; Wu, Liwei; Liu, Tong; Xu, Shizan; Li, Jingjing; Li, Sainan; Wang, Wenwen; Lu, Xiya; Yu, Qiang; Liu, Ning; Xu, Ling; Wang, Fan; Dai, Weiqi; Xia, Yujing; Fan, Xiaoming; Guo, Chuanyong

2018-01-01

Salidroside (Sal) is a glycoside extract from Rhodiola rosea L. with anti-inflammatory, antioxidant, anticancer and cardioprotective properties. The present study explored the protective effects and the possible mechanisms of Sal on concanavalin A (ConA)-induced liver injury in mice. Balb/C mice were divided into five groups: Normal control (injected with normal saline), ConA (25 mg/kg), Sal (10 mg/kg) +ConA, Sal (20 mg/kg) + ConA (Sal injected 2 h prior to ConA injection) and Sal (20 mg/kg) only. The serum levels of liver enzymes, pro-inflammatory cytokines, and apoptosis- and autophagy-associated marker proteins were determined at 2, 8 and 24 h after ConA injection. LY294002 was further used to verify whether the phosphoinositide 3-kinase (PI3K)/Akt pathway was activated. Primary hepatocytes were isolated to verify the effect of Sal in vitro. The results indicated that Sal was a safe agent to reduce pathological damage and serum liver enzymes in ConA-induced liver injury. Sal suppressed inflammatory reactions in serum and liver tissues, and activated the PI3K/Akt signaling pathway to inhibit apoptosis and autophagy in vivo and in vitro, which could be reversed by LY294002. In conclusion, Sal attenuated ConA-induced liver injury by modulating PI3K/Akt pathway-mediated apoptosis and autophagy in mice.

Experimental and Computational Studies of Carbonyl Diazide (CON6) as a Precursor to Diazirinone (CON2)

NASA Astrophysics Data System (ADS)

Esselman, Brian J.; Amberger, Brent K.; Nolan, Alex M.; Woods, R. Claude; McMahon, R. J.

2011-10-01

Intrigued by the reported 2005 synthesis of diazirinone (1), we carried out further experimental and theoretical studies aimed at the detailed matrix-isolation and millimeter-wave spectroscopic characterizations of 1. Diazirinone (1) is a peculiar isoconjugate of two very stable molecules and may be of astrochemical interest. Unfortunately, the original reported methods of diazirinone (1) generation did not yield this species, rather its decomposition products. Inspired by a more recent gas phase pyrolysis of CON6 (2) to yield CON2 (1), we proposed a new method of generating CON6 (2) in solution as a precursor of diazirinone (1). This new synthesis may allow us to generate larger quantities of both CON6 and CON2 for investigation by millimeter-wave spectroscopy. We are able to safely generate carbonyl diazide (2) in sufficient yield from the reaction of triphosgene (3) and tetrabutylammonium azide in diethyl ether. This has allowed us to obtain both matrix-isolation and gas phase IR spectra of carbonyl diazide (2). After purification, it has a gas-phase lifetime that allows samples to be useable for up to several weeks. However, it is a shock-sensitive material that must be handled with care to prevent violent decomposition. In order to provide better mechanistic insight into the decomposition of carbonyl diazide (2) to diazirinone (1), we have engaged in a DFT and ab initio computational study. We have found a pathway between the two species via the triplet acylnitrene, CON4, and an oxaziridine CON2 species, but not at sufficiently low energies to allow for the trapping and detection of diazirinone (1). Preliminary millimeter-wave spectra have been obtained from several synthesized and purified samples of CON6 (2). However, the assignment of the spectra lines has been unexpectedly problematic. We have placed several CON6 (2) samples, confirmed by IR spectroscopy at the time of sample loading, into our instrument and obtained two different sets of rotational lines. This rotational puzzle will be investigated further with a significantly upgraded millimeter-wave spectrometer.

Heat acclimation attenuates physiological strain and the HSP72, but not HSP90α, mRNA response to acute normobaric hypoxia.

PubMed

Gibson, Oliver R; Turner, Gareth; Tuttle, James A; Taylor, Lee; Watt, Peter W; Maxwell, Neil S

2015-10-15

Heat acclimation (HA) attenuates physiological strain in hot conditions via phenotypic and cellular adaptation. The aim of this study was to determine whether HA reduced physiological strain, and heat shock protein (HSP) 72 and HSP90α mRNA responses in acute normobaric hypoxia. Sixteen male participants completed ten 90-min sessions of isothermic HA (40°C/40% relative humidity) or exercise training [control (CON); 20°C/40% relative humidity]. HA or CON were preceded (HYP1) and proceeded (HYP2) by a 30-min normobaric hypoxic exposure [inspired O2 fraction = 0.12; 10-min rest, 10-min cycling at 40% peak O2 uptake (V̇O2 peak), 10-min cycling at 65% V̇O2 peak]. HA induced greater rectal temperatures, sweat rate, and heart rates (HR) than CON during the training sessions. HA, but not CON, reduced resting rectal temperatures and resting HR and increased sweat rate and plasma volume. Hemoglobin mass did not change following HA nor CON. HSP72 and HSP90α mRNA increased in response to each HA session, but did not change with CON. HR during HYP2 was lower and O2 saturation higher at 65% V̇O2 peak following HA, but not CON. O2 uptake/HR was greater at rest and 65% V̇O2 peak in HYP2 following HA, but was unchanged after CON. At rest, the respiratory exchange ratio was reduced during HYP2 following HA, but not CON. The increase in HSP72 mRNA during HYP1 did not occur in HYP2 following HA. In CON, HSP72 mRNA expression was unchanged during HYP1 and HYP2. In HA and CON, increases in HSP90α mRNA during HYP1 were maintained in HYP2. HA reduces physiological strain, and the transcription of HSP72, but not HSP90α mRNA in acute normobaric hypoxia. Copyright © 2015 the American Physiological Society.

Planificación Neuroquirúrgica con Software Osirix

PubMed Central

Jaimovich, Sebastián Gastón; Guevara, Martin; Pampin, Sergio; Jaimovich, Roberto; Gardella, Javier Luis

2014-01-01

Introducción: La individualidad anatómica es clave para reducir el trauma quirúrgico y obtener un mejor resultado. Actualmente, el avance en las neuroimágenes ha permitido objetivar esa individualidad anatómica, permitiendo planificar la intervención quirúrgica. Con este objetivo, presentamos nuestra experiencia con el software Osirix. Descripción de la técnica: Se presentan 3 casos ejemplificadores de 40 realizados. Caso 1: Paciente con meningioma de la convexidad parasagital izquierda en área premotora; Caso 2: Paciente con macroadenoma hipofisario, operada previamente por vía transeptoesfenoidal en otra institución con una resección parcial; Caso 3: Paciente con lesiones en pedúnculo cerebeloso medio bilateral. Se realizó la planificación prequirúrgica con el software OsiriX, fusionando y reconstruyendo en 3D las imágenes de TC e IRM, para analizar relaciones anatómicas, medir distancias, coordenadas y trayectorias, entre otras funciones. Discusión: El software OsiriX de acceso libre y gratuito permite al cirujano, mediante la fusión y reconstrucción en 3D de imágenes, analizar la anatomía individual del paciente y planificar de forma rápida, simple, segura y económica cirugías de alta complejidad. En el Caso 1 se pudo analizar las relaciones del tumor con las estructuras adyacentes para minimizar el abordaje. En el Caso 2 permitió comprender la anatomía post-operatoria previa del paciente, para determinar la trayectoria del abordaje transnasal endoscópico y la necesidad de ampliar su exposición, logrando la resección tumoral completa. En el Caso 3 permitió obtener las coordenadas estereotáxicas y trayectoria de una lesión sin representación tomográfica. Conclusión: En casos de no contar con costosos sistemas de neuronavegación o estereotáxia el software OsiriX es una alternativa a la hora de planificar la cirugía, con el objetivo de disminuir el trauma y la morbilidad operatoria. PMID:25165617

Monitoring of precursor landslide surface deformation using InSAR image in Kuchi-Sakamoto, Shizuoka Prefecture, Japan

NASA Astrophysics Data System (ADS)

Sato, H. P.; Nakajima, H.; Nakano, T.; Daimaru, H.

2014-12-01

Synthetic Aperture Radar (SAR) is the technique to obtain ground surface images using microwave that is emitted from and received on the antenna. The Kuchi-Sakamoto area, 2.2 km2 in precipitous mountains, central Japan, has suffered from frequent landslides, and slow landslide surface deformation has been monitored by on-site extensometer; however, such the monitoring method cannot detect the deformation in the whole area. Because satellite InSAR is effective tool to monitor slow landslide suface deformation, it is a promising tool for detecting precursor deformation and preparing effective measures against serious landslide disasters. In this study Advanced Land Observing Satellite (ALOS) / Phased Array type L-band SAR (PALSAR) data were used, and InSAR images were produced from the PALSAR data that were observed between 5 Sep 2008 and 21 Oct 2008 (from descending orbit) and between 20 Jul 2008 and 7 Sep 2009 (from ascending orbit). InSAR image from descending orbit was found to detect clear precursor landslide surface deformation on a slope; however, InSAR image on ascending orbit did not always detect clear precursor deformation. It is thought to be related with atmospheric moisture condition, length of observation baseline and so on. Furthermore, after phase unwrapping on InSAR images, 2.5-dimensional deformation was analized. This analysis needed both ascending and descending InSAR images and culculated quasi east-west deformation component (Figs. (a) and (b)) and quasi up-down deformation component (Figs. (c) and (d)). The resulting 2.5D calculation gave westward deformation and mixture of upward and downward deformations on the precursor landslide surface deformation slope (blue circles in Figs. (c) and (d)), where remarkable disrupted deep landslide occurred during Nov 2012 and 25 Jun 2013, judging from result of airborne LiDAR survey and field survey; the occurrence date is not precisely identified. The figure remains the issue that eliminating "real" precursor deformation from other candidate deformations. Preparation of this paper was supported by part of Individual Research Fund in College of Humanities and Sciences, Nihon University and part of Grants-in-Aid for Scientific Research, Challenging Exploratory (#25560185, Principal Investigator: Dr. Hiromu Daimaru).

Generation of deformation time series from SAR data sequences in areas affected by large dynamics: insights from Sierra Negra caldera, Galápagos Islands

NASA Astrophysics Data System (ADS)

Casu, Francesco; Manconi, Andrea; Pepe, Antonio; Lanari, Riccardo

2010-05-01

Differential Synthetic Aperture Radar Interferometry (DInSAR) is a remote sensing technique that allows producing spatially dense deformation maps of the Earth surface, with centimeter accuracy. To this end, the phase difference of SAR image pairs acquired before and after a deformation episode is properly exploited. This technique, originally applied to investigate single deformation events, has been further extended to analyze the temporal evolution of the deformation field through the generation of displacement time-series. A well-established approach is represented by the Small BAseline Subset (SBAS) technique (Berardino et al., 2002), whose capability to analyze deformation events at low and full spatial resolution has largely been demonstrated. However, in areas where large and/or rapid deformation phenomena occur, the exploitation of the differential interferograms, thus also of the displacement time-series, can be strongly limited by the presence of significant misregistration errors and/or very high fringe rates, making unfeasible the phase unwrapping step. In this work, we propose advances on the generation of deformation time-series in areas affected by large deformation dynamics. We present an extension of the amplitude-based Pixel-Offset analyses by applying the SBAS strategy, in order to move from the investigation of single (large) deformation events to that of dynamic phenomena. The above-mentioned method has been tested on an ENVISAT SAR data archive (Track 61, Frames 7173-7191) related to the Galapagos Islands, focusing on Sierra Negra caldera (Galapagos Islands), an active volcanic area often characterized by large and rapid deformation events leading to severe image misregistration effects (Yun et al., 2007). Moreover, we present a cross-validation of the retrieved deformation estimates comparing our results to continuous GPS measurements and to synthetic deformation obtained by independently modeling the interferometric phase information when available. References: P. Berardino et al., (2002), A new algorithm for Surface Deformation Monitoring based on Small Baseline Differential SAR Interferograms, IEEE Transactions on Geoscience and Remote Sensing, vol. 40, 11, pp. 2375-2383. S-H. Yun et al., (2007), Interferogram formation in the presence of complex and large deformation, Geophys. Res. Lett., vol. 34, L12305.

Paleohydrologic controls on soft-sediment deformation in the Navajo Sandstone

NASA Astrophysics Data System (ADS)

Bryant, Gerald; Cushman, Robert; Nick, Kevin; Miall, Andrew

2016-10-01

Many workers have noted the presence of contorted cross-strata in the Navajo Sandstone and other ancient eolianites, and have recognized their significance as indicators of sediment saturation during the accumulation history. Horowitz (1982) proposed a general model for the production of such features in ancient ergs by episodic, seismically induced liquefaction of accumulated sand. A key feature of that popular model is the prevalence of a flat water table, characteristic of a hyper-arid climatic regime, during deformation. Under arid climatic conditions, the water table is established by regional flow and liquefaction is limited to the saturated regions below the level of interdune troughs. However, various paleohydrological indicators from Navajo Sandstone outcrops point toward a broader range of water table configurations during the deformation history of that eolianite. Some outcrops reveal extensive deformation complexes that do not appear to have extended to the contemporary depositional surface. These km-scale zones of deformation, affecting multiple sets of cross-strata, and grading upward into undeformed crossbeds may represent deep water table conditions, coupled with high intensity triggers, which produced exclusively intrastratal deformation. Such occurrences contrast with smaller-scale complexes formed within the zone of interaction between the products of soft-sediment deformation and surface processes of deposition and erosion. The Horowitz model targets the smaller-scale deformation morphologies produced in this near-surface environment. This study examines the implications of a wet climatic regime for the Horowitz deformation model. It demonstrates how a contoured water table, characteristic of humid climates, may have facilitated deformation within active bedforms, as well as in the accumulation. Intra-dune deformation would enable deflation of deformation features during the normal course of dune migration, more parsimoniously accounting for: the frequent occurrence of erosionally truncated deformation structures in the Navajo Sandstone; the production of such erosional truncations during bedform climb and aggradation of the accumulation; and the dramatic fluctuations in the water table required to deposit dry eolian sand, deform those deposits under saturated conditions, and then dry the deformed sand to enable deflation.

Strain partitioning and deformation mode analysis of the normal faults at Red Mountain, Birmingham, Alabama

NASA Astrophysics Data System (ADS)

Wu, Schuman

1989-12-01

In a low-temperature environment, the thin-section scale rock-deformation mode is primarily a function of confining pressure and total strain at geological strain rates. A deformation mode diagram is constructed from published experimental data by plotting the deformation mode on a graph of total strain versus the confining pressure. Four deformation modes are shown on the diagram: extensional fracturing, mesoscopic faulting, incipient faulting, and uniform flow. By determining the total strain and the deformation mode of a naturally deformed sample, the confining pressure and hence the depth at which the rock was deformed can be evaluated. The method is applied to normal faults exposed on the gently dipping southeast limb of the Birmingham anticlinorium in the Red Mountain expressway cut in Birmingham, Alabama. Samples of the Ordovician Chickamauga Limestone within and adjacent to the faults contain brittle structures, including mesoscopic faults and veins, and ductile deformation features including calcite twins, intergranular and transgranular pressure solution, and deformed burrows. During compaction, a vertical shortening of about 45 to 80% in shale is indicated by deformed burrows and relative compaction of shale to burrows, about 6% in limestone by stylolites. The normal faults formed after the Ordovician rocks were consolidated because the faults and associated veins truncate the deformed burrows and stylolites, which truncate the calcite cement. A total strain of 2.0% was caused by mesoscopic faults during normal faulting. A later homogenous deformation, indicated by the calcite twins in veins, cement and fossil fragments, has its major principal shortening strain in the dip direction at a low angle (about 22°) to bedding. The strain magnitude is about 2.6%. By locating the observed data on the deformation mode diagram, it is found that the normal faulting characterized by brittle deformation occurred under low confining pressure (< 18 MPa) at shallow depth (< 800 m), and the homogenous horizontal compression characterized by uniform flow occurred under higher confining pressure (at least 60 MPa) at greater depth (> 2.5 km).

Hemi-wedge osteotomy in the management of large angular deformities around the knee joint.

PubMed

El-Alfy, Barakat Sayed

2016-08-01

Angular deformity around the knee joint is a common orthopedic problem. Many options are available for the management of such problem with varying degrees of success and failure. The aim of the present study was to assess the results of hemi-wedge osteotomy in the management of big angular deformities about the knee joint. Twenty-eight limbs in 21 patients with large angular deformities around the knee joint were treated by the hemi-wedge osteotomy technique. The ages ranged from 12 to 43 years with an average of 19.8 years. The deformity ranged from 20° to 40° with a mean of 30.39° ± 5.99°. The deformities were genu varum in 12 cases and genu valgum in 9 cases. Seven cases had bilateral deformities. Small wedge was removed from the convex side of the bone and put in the gap created in the other side after correction of the deformity. At the final follow-up, the deformity was corrected in all cases except two. Full range of knee movement was regained in all cases. The complications included superficial wound infection in two cases, overcorrection in one case, pain along the lateral aspect of the knee in one case and recurrence of the deformity in one case. No cases were complicated by nerve injury or vascular injury. Hemi-wedge osteotomy is a good method for treatment of deformities around the knee joint. It can correct large angular deformities without major complications.

Deformation of volcanic materials by pore pressurization: analog experiments with simplified geometry

NASA Astrophysics Data System (ADS)

Hyman, David; Bursik, Marcus

2018-03-01

The pressurization of pore fluids plays a significant role in deforming volcanic materials; however, understanding of this process remains incomplete, especially scenarios accompanying phreatic eruptions. Analog experiments presented here use a simple geometry to study the mechanics of this type of deformation. Syrup was injected into the base of a sand medium, simulating the permeable flow of fluids through shallow volcanic systems. The experiments examined surface deformation over many source depths and pressures. Surface deformation was recorded using a Microsoft® Kinect™ sensor, generating high-spatiotemporal resolution lab-scale digital elevation models (DEMs). The behavior of the system is controlled by the ratio of pore pressure to lithostatic loading (λ =p/ρ g D). For λ <10, deformation was accommodated by high-angle, reversed-mechanism shearing along which fluid preferentially flowed, leading to a continuous feedback between deformation and pressurization wherein higher pressure ratios yielded larger deformations. For λ >10, fluid expulsion from the layer was much faster, vertically fracturing to the surface with larger pressure ratios yielding less deformation. The temporal behavior of deformation followed a characteristic evolution that produced an approximately exponential increase in deformation with time until complete layer penetration. This process is distinguished from magmatic sources in continuous geodetic data by its rapidity and characteristic time evolution. The time evolution of the experiments compares well with tilt records from Mt. Ontake, Japan, in the lead-up to the deadly 2014 phreatic eruption. Improved understanding of this process may guide the evolution of magmatic intrusions such as dikes, cone sheets, and cryptodomes and contribute to caldera resurgence or deformation that destabilizes volcanic flanks.

Altered ventral neck muscle deformation for individuals with whiplash associated disorder compared to healthy controls - a case-control ultrasound study.

PubMed

Peterson, Gunnel; Dedering, Åsa; Andersson, Erika; Nilsson, David; Trygg, Johan; Peolsson, Michael; Wallman, Thorne; Peolsson, Anneli

2015-04-01

Previous studies have shown altered neck muscle function in individuals with chronic whiplash associated disorder (WAD). However, we lack real-time investigations with non-invasive methods that can distinguish between the different ventral neck muscle layers. This study investigated deformations and deformation rates in the sternocleidomastoid (SCM), longus capitis (Lcap), and longus colli (Lco) muscles with real-time ultrasonography. Twenty-six individuals with WAD were compared with 26 controls, matched for age and sex. Ultrasound imaging of the SCM, Lcap, and Lco were recorded during 10 repetitive arm elevations. The first and tenth arm elevations were post-process analyzed with speckle tracking. There were few significant differences in the deformations or deformation rates in the SCM, Lcap, and Lco between the WAD and control group. In controls, deformations and deformation rates showed linear positive relationships between SCM/Lcap, SCM/Lco, and Lcap/Lco which increased from the first arm elevation (R(2) = 0.14-0.70); to the tenth arm elevation (R(2) = 0.51-0.71). The WAD group showed similar or weaker linear relationship (R(2) < 0.19) during the tenth compared to the first (R(2) < 0.44) arm elevation except for deformations in Lcap/Lco (R(2) = 0.13-0.57). This result indicated that deformations and deformation rates in one muscle were correlated by similar deformations and deformation rates in other neck muscles in the control group, but this interplay between muscles was not found in the WAD group. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of deformation path on microstructure, microhardness and texture evolution of interstitial free steel fabricated by differential speed rolling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamad, Kotiba; Chung, Bong Kwon; Ko, Young Gun, E-mail: younggun@ynu.ac.kr

2014-08-15

This paper reports the effect of the deformation path on the microstructure, microhardness, and texture evolution of interstitial free (IF) steel processed by differential speed rolling (DSR) method. For this purpose, total height reductions of 50% and 75% were imposed on the samples by a series of differential speed rolling operations with various height reductions per pass (deformation levels) ranging from 10 to 50% under a fixed roll speed ratio of 1:4 for the upper and lower rolls, respectively. Microstructural observations using transmission electron microscopy and electron backscattered diffraction measurements showed that the samples rolled at deformation level of 50%more » had the finest mean grain size (∼ 0.5 μm) compared to the other counterparts; also the samples rolled at deformation level of 50% showed a more uniform microstructure. Based on the microhardness measurements along the thickness direction of the deformed samples, gradual evolution of the microhardness value and its homogeneity was observed with the increase of the deformation level per pass. Texture analysis showed that, as the deformation level per pass increased, the fraction of alpha fiber and gamma fiber in the deformed samples increased. The textures obtained by the differential speed rolling process under the lubricated condition would be equivalent to those obtained by the conventional rolling. - Highlights: • Effect of DSR deformation path on microstructure of IF steel is significant. • IF steel rolled at deformation level of 50% has the ultrafine grains of ∼ 0.5 μm. • Rolling texture components are pronounced with increasing deformation level.« less

From micron to mountain-scale, using accessory phase petrochronology to quantify the rates of deformation in the Himalaya and beyond

NASA Astrophysics Data System (ADS)

Mottram, C. M.

2016-12-01

Mountains form where the Earth's plates collide; during this upheaval rocks are deformed by massive forces. The rates and timescales over which these deformational processes occur are determined from tiny accessory minerals that record geological time through radioactive decay. However, there remain major unresolved challenges in using chemical and microstructural markers to link the dates yielded from these accessory phases to specific deformation events and discerning the effects of deformation on the isotopic and elemental tracers in these phases. Here, the chemical signatures and deformation textures from micron-scale accessory phases are used to decode the record of mountain belt-scale deformational processes encrypted in the rocks. The Himalayan orogen is used as an ideal natural laboratory to understand the chemical processes that have modified the Earth's crust during orogenesis. Combined laser ablation split-stream U-Th-Pb and REE analysis of deformed monazite and titanite, along with Electron BackScatter Diffraction (EBSD) imaging and Pressure-Temperature (P-T) phase equilibria modelling are used to: (1) link accessory phase `age' to `metamorphic stage'; (2) to quantify the influence of deformation on monazite (re)crystallisation mechanisms and its subsequent effect on the crystallographic structure, ages and trace-element distribution in individual grains; and (3) understand how deformation is accommodated through different chemical and structural processes that operate at varying scales through time. This study highlights the importance of fully integrating the pressure-temperature-time-deformation history of multiple accessory phases to better interpret the deformational history of the cores of evolving mountain belts.

Computation of Static Shapes and Voltages for Micromachined Deformable Mirrors with Nonlinear Electrostatic Actuators

NASA Technical Reports Server (NTRS)

Wang, P. K. C.; Hadaegh, F. Y.

1996-01-01

In modeling micromachined deformable mirrors with electrostatic actuators whose gap spacings are of the same order of magnitude as those of the surface deformations, it is necessary to use nonlinear models for the actuators. In this paper, we consider micromachined deformable mirrors modeled by a membrane or plate equation with nonlinear electrostatic actuator characteristics. Numerical methods for computing the mirror deformation due to given actuator voltages and the actuator voltages required for producing the desired deformations at the actuator locations are presented. The application of the proposed methods to circular deformable mirrors whose surfaces are modeled by elastic membranes is discussed in detail. Numerical results are obtained for a typical circular micromachined mirror with electrostatic actuators.

A novel orthogonal transmission-virtual grating method and its applications in measuring micro 3-D shape of deformed liquid surface

NASA Astrophysics Data System (ADS)

Liu, Zhanwei; Huang, Xianfu; Xie, Huimin

2013-02-01

Deformed liquid surface directly involves the surface tension, which can always be used to account for the kinematics of aquatic insects in gas-liquid interface and the light metal floating on the water surface. In this paper a novel method based upon deformed transmission-virtual grating is proposed for determination of deformed liquid surface. By addressing an orthogonal grating (1-5 line/mm) under the transparent water groove and then capturing images from upset of the deformed water surface, a displacement vector of full-field which directly associates the 3-D deformed liquid surface then can be evaluated by processing the recorded deformed fringe pattern in the two directions (x- and y-direction). Theories and equations for the method are thoroughly delivered. Validation test to measure the deformed water surface caused by a Chinese 1-cent coin has been conducted to demonstrate the ability of the developed method. The obtained results show that the method is robust in determination of micro 3-D surface of deformed liquid with a submicron scale resolution and with a wide range application scope.

The anelastic Ericksen problem: universal eigenstrains and deformations in compressible isotropic elastic solids

PubMed Central

2016-01-01

The elastic Ericksen problem consists of finding deformations in isotropic hyperelastic solids that can be maintained for arbitrary strain-energy density functions. In the compressible case, Ericksen showed that only homogeneous deformations are possible. Here, we solve the anelastic version of the same problem, that is, we determine both the deformations and the eigenstrains such that a solution to the anelastic problem exists for arbitrary strain-energy density functions. Anelasticity is described by finite eigenstrains. In a nonlinear solid, these eigenstrains can be modelled by a Riemannian material manifold whose metric depends on their distribution. In this framework, we show that the natural generalization of the concept of homogeneous deformations is the notion of covariantly homogeneous deformations—deformations with covariantly constant deformation gradients. We prove that these deformations are the only universal deformations and that they put severe restrictions on possible universal eigenstrains. We show that, in a simply-connected body, for any distribution of universal eigenstrains the material manifold is a symmetric Riemannian manifold and that in dimensions 2 and 3 the universal eigenstrains are zero-stress. PMID:28119554

Steady state deformation of the Coso Range, east central California, inferred from satellite radar interferometry

USGS Publications Warehouse

Wicks, C.W.; Thatcher, W.; Monastero, F.C.; Hasting, M.A.

2001-01-01

Observations of deformation from 1992 to 1997 in the southern Coso Range using satellite radar interferometry show deformation rates of up to 35 mm yr-1 in an area ???10 km by 15 km. The deformation is most likely the result of subsidence in an area around the Coso geothermal field. The deformation signal has a short-wavelength component, related to production in the field, and a long-wavelength component, deforming at a constant rate, that may represent a source of deformation deeper than the geothermal reservoir. We have modeled the long-wavelength component of deformation and inferred a deformation source at ???4 km depth. The source depth is near the brittle-ductile transition depth (inferred from seismicity) and ???1.5 km above the top of the rhyolite magma body that was a source for the most recent volcanic eruption in the Coso volcanic field [Manley and Bacon, 2000]. From this evidence and results of other studies in the Coso Range, we interpret the source to be a leaking deep reservoir of magmatic fluids derived from a crystallizing rhyolite magma body.

[Modern unicondylar knee arthroplasty. Tips and tricks].

PubMed

von Knoch, F; Munzinger, U

2014-05-01

Unicondylar knee arthroplasty (UKA) is an established therapeutic option for advanced medial or lateral gonarthrosis. The cornerstones of a successful UKA, careful patient selection, preoperative planning and precise operation technique, are discussed in this overview article. In contrast to total knee arthroplasty, UKA allows preservation of the contralateral and patellofemoral compartments as well as the cruciate ligaments and is often associated with rapid postoperative recovery, improved knee kinematics and knee function. However, UKA is technically very demanding. High revision rates have been reported in particular with widespread application, according to national joint replacement registries. Successful UKA relies on meticulous patient selection, preoperative planning and surgical technique. It is justified to broaden classic UKA indications. In medial and lateral UKA three types of mechanical varus-valgus deformity can be encountered: type 1 (isolated intraarticular deformity), type 2 (pronounced deformity due to extraarticular varus deformity in medial UKA or valgus deformity in lateral UKA), type 3 (reduced deformity due to extraarticular valgus deformity in medial UKA or varus deformity in lateral UKA). We believe these deformities should be addressed accordingly with surgical technique.

Efficient Killing of Planktonic and Biofilm-Embedded Coagulase-Negative Staphylococci by Bactericidal Protein P128

PubMed Central

Poonacha, Nethravathi; Nair, Sandhya; Desai, Srividya; Tuppad, Darshan; Hiremath, Deepika; Mohan, Thulasi; Vipra, Aradhana

2017-01-01

ABSTRACT Coagulase-negative staphylococci (CoNS) are the major causative agents of foreign-body-related infections, including catheter-related bloodstream infections. Because of the involvement of biofilms, foreign-body-related infections are difficult to treat. P128, a chimeric recombinant phage-derived ectolysin, has been shown to possess bactericidal activity on strains of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). We tested the killing potential of P128 on three clinically significant species of CoNS, S. epidermidis, S. haemolyticus, and S. lugdunensis, under a variety of physiological conditions representing growing and nongrowing states. The MIC90 and minimum bactericidal concentration at which 90% of strains tested are killed (MBC90) of P128 on 62 clinical strains of CoNS were found to be 16 and 32 μg/ml (0.58 and 1.16 μM), respectively, demonstrating the bactericidal nature of P128 on CoNS strains. Serum showed a potentiating effect on P128 inhibition, as indicated by 4- to 32-fold lower MIC values observed in serum. P128 caused a rapid loss of viability in all CoNS strains tested. Persisters of CoNS that were enriched in the presence of vancomycin or daptomycin were killed by P128 at 1× the MIC in a rapid manner. Low concentrations of P128 caused a 2- to 5-log reduction in CFU in stationary-phase or poorly metabolizing CoNS cultures. P128 at low concentrations eliminated CoNS biofilms in microtiter plates and on the surface of catheters. Combinations of P128 and standard-of-care (SoC) antibiotics were highly synergistic in inhibiting growth in preformed biofilms. Potent activity on planktonic cells, persisters, and biofilms of CoNS suggests that P128 is a promising candidate for the clinical development of treatments for foreign-body-related and other CoNS infections. PMID:28559263

The role of the 2H4 molecule in the generation of suppressor function in Con A-activated T cells.

PubMed

Morimoto, C; Letvin, N L; Rudd, C E; Hagan, M; Takeuchi, T; Schlossman, S F

1986-11-15

The molecular basis for the suppression generated in a concanavalin A (Con A)-activated T cell culture remains unknown. In this study, we have attempted to determine whether the 2H4 and 4B4 molecules on Con A-activated T cells play some role in the generation of suppression by such cells. We have shown that Con A-activated suppressor cells belong to the 2H4+ subset of T cells but not the 4B4+ (2H4-) subset. Con A-activated T cells exerted their optimal suppressor function on day 2 in culture, a time at which the expression of 2H4 on such cells was maximal and 4B4 was minimal. Furthermore, the stimulation of T cells with the higher concentration of Con A generated the stronger suppressor function. At the same time, both 2H4 expression and density were increased and 4B4 expression and density were decreased on such Con A-activated T cells. More importantly, the treatment of Con A-activated T cells with anti-2H4 antibody but not with anti-4B4, anti-TQ1, or anti-T4 antibodies can block the suppressor function of such cells. Taken together, the above results strongly suggest that the 2H4 molecule itself may be involved in the generation of suppressor function in Con A-activated T cells. The 2H4 antigen on such cells was shown to be comprised of 220,000 and 200,000 m.w. glycoproteins. Thus this study indicates that the 220,000 and 200,000 m.w. structure of the 2H4 molecule may itself play a crucial role in the generation of suppressor signals of Con A-activated cells.

Crushed Ice Ingestion Does Not Improve Female Cycling Time Trial Performance in the Heat.

PubMed

Zimmermann, Matthew; Landers, Grant Justin; Wallman, Karen Elizabeth

2017-02-01

This study examined the effects of precooling via ice ingestion on female cycling performance in hot, humid conditions. Ten female endurance athletes, mean age (28 ± 6 y), height (167.6 ± 6.5 cm) and body-mass (68.0 ± 11.5 kg) participated in the study. Participants completed an 800 kJ cycle time-trial in hot, humid conditions (34.9 ± 0.3 °C, 49.8 ± 3.5% RH). This was preceded by the consumption of 7 g∙kg -1 of crushed ice (ICE) or water (CON). There was no difference in performance time (CON 3851 ± 449 s; ICE 3767 ± 465 s), oxygen consumption (CON 41.6 ± 7.0 ml∙kg∙min -1 ; ICE 42.4 ± 6.0 ml∙kg∙min -1 ) or respiratory exchange ratio (CON 0.88 ± 0.05; ICE 0.90 ± 0.06) between conditions (p > .05, d < 0.5). Core and skin temperature following the precooling period were lower in ICE (T c 36.4 ± 0.4 °C; T sk 31.6 ± 1.2 °C) compared with CON (T c 37.1 ± 0.4 °C; T sk 32.4 ± 0.7 °C) and remained lower until the 100 kJ mark of the cycle time-trial (p < .05, d > 1.0). Sweat onset occurred earlier in CON (228 ± 113 s) compared with ICE (411 ± 156 s) (p < .05, d = 1.63). Mean thermal sensation (CON 1.8 ± 2.0; ICE 1.2 ± 2.5, p < .05, d = 2.51), perceived exertion (CON 15.3 ± 2.9; ICE 14.9 ± 3.0, p < .05, d = 0.38) and perceived thirst (CON 5.6 ± 2.2; ICE 4.6 ± 2.4, p < .05, d = 0.98) were lower in ICE compared with CON. Crushed ice ingestion did not improve cycling performance in females, although perceptual responses were reduced.

Evaluation of Houttuynia cordata and Taraxacum officinale on Growth Performance, Nutrient Digestibility, Blood Characteristics, and Fecal Microbial Shedding in Diet for Weaning Pigs.

PubMed

Yan, L; Zhang, Z F; Park, J C; Kim, I H

2012-10-01

A total of 144 pigs ((Landrace×Yorkshire)×Duroc] with an average initial BW of 8.45±0.57 kg were used in a 5-wk growth trial. Pigs were randomly allocated to 4 treatments with 9 replications per pen in a randomized complex block design. Dietary treatments included: i) CON (basal diet), ii) ANT (CON+tylosin 1 g/kg), iii) H1 (CON+H. cordata 1 g/kg) and iv) T1 (CON+T. officinale 1 g/kg). In this study, pigs fed the ANT and T1 treatment had a higher (p<0.05) average daily gain (ADG) and gain:feed (G:F) ratio than those fed CON and H1 treatment. Dietary ANT and T1 treatment led to a higher energy digestibility than the CON group. No difference (p>0.05) was observed on the growth performance and apparent total tract digestibility with H1 supplementation compared with the CON treatment. The inclusion of ANT treatment led to a higher (p<0.05) lymphocyte concentration compared with the CON treatment. Dietary supplementation of herbs did not affect (p>0.05) the blood characteristics (white blood cell (WBC), red blood cell (RBC), IgG, lymphocyte). No difference was observed on (p<0.05) fecal microbial shedding (E. coli and lactobacillus) between ANT and CON groups. Treatments H1 and T1 reduced the fecal E. coli concentration compared with the CON treatment, whereas the fecal lactobacillus concentration was not affected by the herb supplementation (p>0.05). In conclusion, the inclusion of T. officinale (1 g/kg) increased growth performance, feed efficiency, energy digestibility similarly to the antibiotic treatment. Dietary supplementation of T. officinale and H. cordata (1 g/kg) reduced the fecal E. coli concentration in weaning pigs.

Evaluation of Houttuynia cordata and Taraxacum officinale on Growth Performance, Nutrient Digestibility, Blood Characteristics, and Fecal Microbial Shedding in Diet for Weaning Pigs

PubMed Central

Yan, L.; Zhang, Z. F.; Park, J. C.; Kim, I. H.

2012-01-01

A total of 144 pigs ((Landrace×Yorkshire)×Duroc] with an average initial BW of 8.45±0.57 kg were used in a 5-wk growth trial. Pigs were randomly allocated to 4 treatments with 9 replications per pen in a randomized complex block design. Dietary treatments included: i) CON (basal diet), ii) ANT (CON+tylosin 1 g/kg), iii) H1 (CON+H. cordata 1 g/kg) and iv) T1 (CON+T. officinale 1 g/kg). In this study, pigs fed the ANT and T1 treatment had a higher (p<0.05) average daily gain (ADG) and gain:feed (G:F) ratio than those fed CON and H1 treatment. Dietary ANT and T1 treatment led to a higher energy digestibility than the CON group. No difference (p>0.05) was observed on the growth performance and apparent total tract digestibility with H1 supplementation compared with the CON treatment. The inclusion of ANT treatment led to a higher (p<0.05) lymphocyte concentration compared with the CON treatment. Dietary supplementation of herbs did not affect (p>0.05) the blood characteristics (white blood cell (WBC), red blood cell (RBC), IgG, lymphocyte). No difference was observed on (p<0.05) fecal microbial shedding (E. coli and lactobacillus) between ANT and CON groups. Treatments H1 and T1 reduced the fecal E. coli concentration compared with the CON treatment, whereas the fecal lactobacillus concentration was not affected by the herb supplementation (p>0.05). In conclusion, the inclusion of T. officinale (1 g/kg) increased growth performance, feed efficiency, energy digestibility similarly to the antibiotic treatment. Dietary supplementation of T. officinale and H. cordata (1 g/kg) reduced the fecal E. coli concentration in weaning pigs. PMID:25049500

Generation and Characterization of HIV-1 Transmitted and Founder Virus Consensus Sequence from Intravenous Drug Users in Xinjiang, China.

PubMed

Li, Fan; Ma, Liying; Feng, Yi; Hu, Jing; Ni, Na; Ruan, Yuhua; Shao, Yiming

2017-06-01

HIV-1 transmission in intravenous drug users (IDUs) has been characterized by high genetic multiplicity and suggests a greater challenge for HIV-1 infection blocking. We investigated a total of 749 sequences of full-length gp160 gene obtained by single genome sequencing (SGS) from 22 HIV-1 early infected IDUs in Xinjiang province, northwest China, and generated a transmitted and founder virus (T/F virus) consensus sequence (IDU.CON). The T/F virus was classified as subtype CRF07_BC and predicted to be CCR5-tropic virus. The variable region (V1, V2, and V4 loop) of IDU.CON showed length variation compared with the heterosexual T/F virus consensus sequence (HSX.CON) and homosexual T/F virus consensus sequence (MSM.CON). A total of 26 N-linked glycosylation sites were discovered in the IDU.CON sequence, which is less than that of MSM.CON and HSX.CON. Characterization of T/F virus from IDUs highlights the genetic make-up and complexity of virus near the moment of transmission or in early infection preceding systemic dissemination and is important toward the development of an effective HIV-1 preventive methods, including vaccines.

Comparison of slime-producing coagulase-negative Staphylococcus colonization rates on vinyl and ceramic tile flooring materials.

PubMed

Yazgi, H; Uyanik, M H; Ayyildiz, A

2009-01-01

This study investigated the colonization of slime-producing coagulase-negative Staphylococcus (CoNS) in 80 patient wards in Turkey (40 vinyl and 40 ceramic tile floors). A total of 480 samples that included 557 CoNS isolates were obtained. Slime production was investigated with the Christensen method and methicillin-susceptibility was tested by the disk-diffusion method. There was a significant difference in the percentage of slime-producing CoNS isolates on vinyl (12.4%) versus ceramic tile flooring (4.4%). From vinyl flooring, the percentage of slime producing methicillin-resistant CoNS (MRCoNS) (8.9%) was significantly higher than for methicillin-sensitive CoNS (MSCoNS) (3.6%), whereas there was no difference from ceramic tile flooring (2.5% MRCoNS versus 1.8% MSCoNS). The most commonly isolated slime-producing CoNS species was S. epidermidis on both types of flooring. It is concluded that vinyl flooring seems to be a more suitable colonization surface for slime-producing CoNS than ceramic tile floors. Further studies are needed to investigate bacterial strains colonized on flooring materials, which are potential pathogens for nosocomial infections.

B cells as accessory cells in a Con A response of a T cell clone.

PubMed

Takeuchi, M; Kakiuchi, T; Taira, S; Nariuchi, H

1987-12-01

Accessory cell (AC) function of B cells was examined in Con A response of a cloned T cell line, 22-9D, which is Thy 1+,L3T4+,Lyt2-,H-2KbDb+ and I-Ab-.22-9D cells produced IL 2 in the presence of Con A without participation of AC. For the initiation of a proliferative response to Con A, the addition of spleen cells or spleen adherent cells was required. B cells as AC were unable to induce the proliferative response. In the presence of culture supernatant of spleen cells stimulated with Con A (CAS), 22-9D cells showed proliferative response to Con A with B cell AC. The response was inhibited by a relevant monoclonal anti-I-A antibody. Although irradiated spleen cells as AC induced IL 2 receptor expression of 22-9D cells in the presence of Con A, B cells were shown to require the addition of unknown factor(s) in CAS, which was suggested to be different from IL 1, IL 2, IL 3, or IFN-gamma, for the induction of the receptor expression on 22-9D cells.

Tectonic evolution of the Arizaro basin of the Puna plateau, NW Argentina: Implications for plateau-scale processes

NASA Astrophysics Data System (ADS)

Boyd, John D.

Sedimentary basins of the Altiplano-Puna Plateau within the Andean Plateau in South America contain the record of retro-arc foreland basin evolution during the Cenozoic. The deformation of these basins is characterized by high angle reverse faults and thrusts deforming crystalline basement and sedimentary covers. The mechanism/s responsible for deformation within the region are not fully understood in detail. The relative abundance of intercalated tuffs within these basins and those within the bounding Eastern Cordillera enables the spatial-temporal pattern of deformation across the orogen to be constrained. This study uses the systematic combination of structural, geochronologic and sedimentalogical techniques applied to Cenozoic sedimentary rocks within the Arizaro Basin to investigate the timing of deformation across within the region in order to test two end member models for basin deformation in response to lithospheric processes. The first model attributes the deformation of the basins to internal deformation within an orogenic wedge as part of the taper building process required prior to propagation eastward towards the foreland basin system. The second model attributes basin deformation to isostatic adjustments resulting from small-scale lithospheric foundering. Detailed geologic mapping of the Arizaro Basin reveals a complex interplay of coeval thick-skinned and thin-skinned deformation, which deforms the thick Miocene succession of fluvial-lacustrine strata in both a brittle and ductile manner. Zircon U-Pb analyses of intercalated tuffs from the Vizcachera Formation reveal that approximately three km of the section was deposited between the Early Miocene (ca. 18.3) and the Middle Miocene (ca. 13.9). One tuff in the uppermost Vizcachera Formation constrains the lower limit of timing of deformation for the Arizaro Basin to be 13.9 +/- 0.7 Ma. When combined with published geochronological data across the Puna Plateau and Eastern Cordillera, the new data presented in this study constrains timing of deformation within the basin and the greater Arizaro area to the Middle Miocene. This study also indicates that the spatial-temporal patterns of deformation are likely the result of a combination of both models mentioned above with critical taper theory dominating early deformation associated with basin formation and small-scale lithospheric foundering dominating the later deformation in the Middle Miocene. Deformation at the wedge tip continues in the Eastern Cordillera seemingly without interruption, suggesting that the effects of the isostatic pull-down associated with small-scale lithospheric foundering is localized and does not significantly affect the taper of the orogenic wedge as a whole. Thus, allowing the normal cycle of orogenic wedge propagation to occur, uninhibited.

Fuzzy model to estimate the number of hospitalizations for asthma and pneumonia under the effects of air pollution.

PubMed

Chaves, Luciano Eustáquio; Nascimento, Luiz Fernando Costa; Rizol, Paloma Maria Silva Rocha

2017-06-22

Predict the number of hospitalizations for asthma and pneumonia associated with exposure to air pollutants in the city of São José dos Campos, São Paulo State. This is a computational model using fuzzy logic based on Mamdani's inference method. For the fuzzification of the input variables of particulate matter, ozone, sulfur dioxide and apparent temperature, we considered two relevancy functions for each variable with the linguistic approach: good and bad. For the output variable number of hospitalizations for asthma and pneumonia, we considered five relevancy functions: very low, low, medium, high and very high. DATASUS was our source for the number of hospitalizations in the year 2007 and the result provided by the model was correlated with the actual data of hospitalization with lag from zero to two days. The accuracy of the model was estimated by the ROC curve for each pollutant and in those lags. In the year of 2007, 1,710 hospitalizations by pneumonia and asthma were recorded in São José dos Campos, State of São Paulo, with a daily average of 4.9 hospitalizations (SD = 2.9). The model output data showed positive and significant correlation (r = 0.38) with the actual data; the accuracies evaluated for the model were higher for sulfur dioxide in lag 0 and 2 and for particulate matter in lag 1. Fuzzy modeling proved accurate for the pollutant exposure effects and hospitalization for pneumonia and asthma approach. Prever o número de internações por asma e pneumonia associadas à exposição a poluentes do ar no município em São José dos Campos, estado de São Paulo. Trata-se de um modelo computacional que utiliza a lógica fuzzy baseado na técnica de inferência de Mamdani. Para a fuzzificação das variáveis de entrada material particulado, ozônio, dióxido de enxofre e temperatura aparente foram consideradas duas funções de pertinência para cada variável com abordagem linguísticas: bom e ruim. Para a variável de saída número internações por asma e pneumonia, foram consideradas cinco funções de pertinências: muito baixo, baixo, médio, alto e muito alto. O número de internações no ano de 2007 foi obtido do Datasus e o resultado fornecido pelo modelo foi correlacionado com os dados reais de internação com defasagem (lag) de zero a dois dias. A acurácia do modelo foi estimada pela curva ROC para cada poluente e nestas defasagens. No ano de 2007 foram registradas 1.710 internações por pneumonia e asma em São José dos Campos, SP, com média diária de 4,9 internações (dp = 2,9). Os dados de saída do modelo mostraram correlação positiva e significativa (r = 0,38) com os dados reais; as acurácias avaliadas para o modelo foram maiores para o dióxido de enxofre nos lag 0 e 2 e para o material particulado no lag 1. Modelagem fuzzy se mostrou acurada para a abordagem de efeitos da exposição aos poluentes e internação por pneumonia e asma.

Study and optimization of the macroscopic electrical response of carbon based nanocomposites for advanced applications

NASA Astrophysics Data System (ADS)

Silva, Jaime Pedro Oliveira da

A presente tese centrou-se no estudo da resposta da constante dieletrica e condutividade eletrica em materiais compositos nos quais o reforco tinha uma elevada proporcao entre comprimento e diametro. O objeto de estudo foi o efeito de um reforco com uma elevada razao entre comprimento e diametro, concentracao e orientacao na resposta eletrica e dieletrica de um composito. Estes compositos tem uma grande importancia no desenvolvimento de materiais para sensores e atuadores. Num primeiro momento da dissertacao, explorou-se a resposta da constante dieletrica de um composito constituido por nanotubos de carbono como reforco e uma matriz polimerica. Verificou-se que um aumento da razao entre comprimento e diametro do reforco tem o efeito de aumentar a constante dieletrica do composito para uma igual fracao volumetrica de reforco. Constatou-se tambem que materiais na fase nematica demonstram uma constante dieletrica mais baixa quando comparados com materiais onde o reforco esta distribuido aleatoriamente. Ficou ainda demonstrado nesta dissertacao que materiais na fase nematica com razoes entre o comprimento e diametro diferentes a constante dieletrica segue uma lei de potencia. Numa segunda fase do trabalho, foi explorada a condutividade de nanocompositos polimericos reforcados com nanotubos de carbono, atraves de um modelo baseado em cilindros impenetraveis. Ficou demonstrado que o modelo e apropriado para descrever a condutividade eletrica de um nanocomposito polimerico reforcado com nanotubos. As simulacoes desenvolvidas demonstram que, aumentando a razao entre o comprimento e o diametro dos nanotubos de carbono, aumenta a condutividade eletrica do nanocomposito. No entanto, verifica-se que aumentando a anisotropia diminui a condutividade, sendo este efeito mais evidente para fracoes volumetricas maiores. Nesta dissertacao comprovou-se ainda que uma microestrutura gerada por um algoritmo de empacotamento sequencial pode ser descrita por um grafo aleatorio e que a condutividade num composito reforcado com nanofibras de carbono pode ser descrito por uma rede de Bethe. Atraves do uso da teoria das redes complexas, chegou-se a uma expressao para o limite de percolacao e, do mesmo modo, demonstrou-se que “hopping” entre fibras adjacentes resulta numa expressao que corresponde a um regime de desordem fraca. No trabalho desenvolvido tambem foi calculado os expoentes criticos, atraves da teoria das redes, para um sistema 3D composto por cilindros impenetraveis com uma interacao de curto alcance, demonstrando que os expoentes criticos estao relacionados por uma relacao de hiperescala comum para 3D e nao pertencem a mesma classe de universalidade como a percolacao numa rede. A aplicacao do modelo desenvolvido a compositos de epoxy reforcada, com diferentes metodos de dispersao de nanofibras de carbono, revelou que os metodos de dispersao usados para preparar os compositos tem uma forte influencia nas propriedades eletricas que podem ser capturadas pelo modelo. Neste contexto, ficou ainda demonstrado que a condutividade eletrica pode ser descrita por um regime de desordem fraca, isto ´e, um regime onde todas as conexoes fibra-fibra participam na condutividade do composito. O modelo desenvolvido foi aplicado igualmente a compositos de poly (vinylidene fluoride) reforcado com nanotubos de carbono com diferentes tratamentos de termicos de oxidacao. Verificou-se que os tratamentos de superficie aumentam o limite de percolacao e diminuem a condutividade. Nesta dissertacao provamos ainda que a condutividade do composito pode ser atribuida a um mecanismo de “hopping”, fortemente afetado pelos tratamentos de superficie dos reforcos.

Measuring skewness of red blood cell deformability distribution by laser ektacytometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E

An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively. (laser biophotonics)

Nonlinear Phase Field Theory for Fracture and Twinning with Analysis of Simple Shear

DTIC Science & Technology

2015-09-01

elasticity; crystal; shear deformation 1. Introduction Cleavage fracture and deformation twinning are two fundamental inelastic deformation mechanisms that...stress [2,3]. Both of these anisotropic mechanisms involve deformation on specific planes (the cleavage plane for fracture or the habit plane for...be the first phase field theory accounting for both fracture and deformation twinning wherein each mechanism is repre- sented by a distinct-order

Thermodynamics of BTZ black holes in gravity’s rainbow

NASA Astrophysics Data System (ADS)

Alsaleh, Salwa

2017-05-01

In this paper, we deform the thermodynamics of a BTZ black hole from rainbow functions in gravity’s rainbow. The rainbow functions will be motivated from the results in loop quantum gravity and noncommutative geometry. It will be observed that the thermodynamics gets deformed due to these rainbow functions, indicating the existence of a remnant. However, the Gibbs free energy does not get deformed due to these rainbow functions, and so the critical behavior from Gibbs does not change by this deformation. This is because the deformation in the entropy cancels out the temperature deformation.

Mechanism of slip and twinning

NASA Technical Reports Server (NTRS)

Rastani, Mansur

1992-01-01

The objectives are to: (1) demonstrate the mechanisms of deformation in body centered cubic (BCC), face centered cubic (FCC), and hexagonal close-packed (HCP)-structure metals and alloys and in some ceramics as well; (2) examine the deformed microstructures (slip lines and twin boundaries) in different grains of metallic and ceramic specimens; and (3) study visually the deformed macrostructure (slip and twin bands) of metals and alloys. Some of the topics covered include: deformation behavior of materials, mechanisms of plastic deformation, slip bands, twin bands, ductile failure, intergranular fracture, shear failure, slip planes, crystal deformation, and dislocations in ceramics.

Deformation cycles of subduction earthquakes in a viscoelastic Earth.

PubMed

Wang, Kelin; Hu, Yan; He, Jiangheng

2012-04-18

Subduction zones produce the largest earthquakes. Over the past two decades, space geodesy has revolutionized our view of crustal deformation between consecutive earthquakes. The short time span of modern measurements necessitates comparative studies of subduction zones that are at different stages of the deformation cycle. Piecing together geodetic 'snapshots' from different subduction zones leads to a unifying picture in which the deformation is controlled by both the short-term (years) and long-term (decades and centuries) viscous behaviour of the mantle. Traditional views based on elastic models, such as coseismic deformation being a mirror image of interseismic deformation, are being thoroughly revised.

Two Back Stress Hardening Models in Rate Independent Rigid Plastic Deformation

NASA Astrophysics Data System (ADS)

Yun, Su-Jin

In the present work, the constitutive relations based on the combination of two back stresses are developed using the Armstrong-Frederick, Phillips and Ziegler’s type hardening rules. Various evolutions of the kinematic hardening parameter can be obtained by means of a simple combination of back stress rate using the rule of mixtures. Thus, a wide range of plastic deformation behavior can be depicted depending on the dominant back stress evolution. The ultimate back stress is also determined for the present combined kinematic hardening models. Since a kinematic hardening rule is assumed in the finite deformation regime, the stress rate is co-rotated with respect to the spin of substructure obtained by incorporating the plastic spin concept. A comparison of the various co-rotational rates is also included. Assuming rigid plasticity, the continuum body consists of the elastic deformation zone and the plastic deformation zone to form a hybrid finite element formulation. Then, the plastic deformation behavior is investigated under various loading conditions with an assumption of the J2 deformation theory. The plastic deformation localization turns out to be strongly dependent on the description of back stress evolution and its associated hardening parameters. The analysis for the shear deformation with fixed boundaries is carried out to examine the deformation localization behavior and the evolution of state variables.

Effect of initial grain size on inhomogeneous plastic deformation and twinning behavior in high manganese austenitic steel with a polycrystalline microstructure

NASA Astrophysics Data System (ADS)

Ueji, R.; Tsuchida, N.; Harada, K.; Takaki, K.; Fujii, H.

2015-08-01

The grain size effect on the deformation twinning in a high manganese austenitic steel which is so-called TWIP (twining induced plastic deformation) steel was studied in order to understand how to control deformation twinning. The 31wt%Mn-3%Al-3% Si steel was cold rolled and annealed at various temperatures to obtain fully recrystallized structures with different mean grain sizes. These annealed sheets were examined by room temperature tensile tests at a strain rate of 10-4/s. The coarse grained sample (grain size: 49.6μm) showed many deformation twins and the deformation twinning was preferentially found in the grains in which the tensile axis is parallel near to [111]. On the other hand, the sample with finer grains (1.8 μm) had few grains with twinning even after the tensile deformation. The electron back scattering diffraction (EB SD) measurements clarified the relationship between the anisotropy of deformation twinning and that of inhomogeneous plastic deformation. Based on the EBSD analysis, the mechanism of the suppression of deformation twinning by grain refinement was discussed with the concept of the slip pattern competition between the slip system governed by a grain boundary and that activated by the macroscopic load.

Games Con Men Play: The Semiosis of Deceptive Interaction.

ERIC Educational Resources Information Center

Hankiss, Agnes

1980-01-01

Analyzes some of the most frequent deceptive interactions as rendered through case histories of male con artists and their victims taken from police records. Discusses the recurrent elements in both the con-games strategies and victims' way of interpreting those strategies. (JMF)

Connected vehicle pilot deployment program phase 1, concept of operations (ConOps) – Tampa (THEA).

DOT National Transportation Integrated Search

2016-02-01

This document describes the Concept of Operations (ConOps) for the Tampa Hillsborough Expressway Authority (THEA) Connected Vehicle (CV) Pilot Deployment. This ConOps describes the current state of operations, establishes the reasons for change, and ...

An Application of Con-Resistant Trust to Improve the Reliability of Special Protection Systems within the Smart Grid

DTIC Science & Technology

2012-06-01

in an effort to be more reliable and efficient. However, with the benefits of this new technology comes added risk . This research utilizes a con ...AN APPLICATION OF CON -RESISTANT TRUST TO IMPROVE THE RELIABILITY OF SPECIAL PROTECTION SYSTEMS WITHIN THE SMART GRID THESIS Crystal M. Shipman...Government and is not subject to copyright protection in the United States AFIT/GCO/ENG/12-22 AN APPLICATION OF CON -RESISTANT TRUST TO IMPROVE THE

Piping Connector

NASA Technical Reports Server (NTRS)

1994-01-01

In Stennis Space Center's Component Test Facility, piping lines carry rocket propellants and high pressure cryogenic fuels. When the lines are chilled to a pretest temperature of 400 degrees below zero, ordinary piping connectors can leak. Under contract to Stennis, Reflange, Inc. developed the T-Con connector, which included a secondary seal that tolerates severe temperature change. Because of the limited need for the large and expensive T-Con product, Reflange also developed the less costly E-Con, a smaller more compact design with the same technical advantages as the T-Con.

PubMed

Bueno Vargas, Pilar; Manzano Martín, Manuel; López-Aliaga, Inmaculada; López Pedrosa, José M ª

2016-09-20

Introducción: la gestación y lactancia están relacionadas con pérdidas temporales en la densidad mineral ósea (DMO) materna. Una suplementación con calcio podría resultar beneficiosa para evitar la pérdida de masa ósea del esqueleto materno. Otros nutrientes como los prebióticos han sido identificados como responsables de un incremento en la absorción de minerales, pudiendo condicionar la mineralización ósea.Objetivo: estudiar el efecto de la suplementación de la dieta materna con el prebiótico inulina enriquecida con oligofructosa, durante la gestación y la lactancia sobre el contenido mineral óseo (CMO) y la DMO al final del periodo de lactancia.Métodos: las ratas gestantes fueron alimentadas con dieta estándar (grupo CC), dieta fortificada en calcio (grupo Ca) o enriquecida con el prebiótico inulina enriquecida con oligofructosa (grupo Pre) hasta el final del periodo de lactancia. Posteriormente se evaluó el CMO y DMO por absorciometría de rayos X (DEXA) y el pH del contenido cecal.Resultados:en términos generales, el grupo Pre presenta los mayores valores absolutos de CMO y DMO de entre los tres grupos, siendo en la tibia significativamente diferentes en los grupos CC y Pre frente al grupo Ca. El pH del contenido cecal del grupo Pre es significativamente inferior al de los grupos CC y Ca.Conclusión:la suplementación con inulina enriquecida con oligofructosa, en condiciones nutricionales no deficientes en calcio, durante la gestación y la lactancia, ejerce una protección del esqueleto materno en las ratas y puede ser considerada como una estrategia nutricional para proteger la masa ósea materna en el periodo perinatal.

Participation of interleukins in synergistic effect of Bu-WSA on concanavalin A-induced DNA synthesis in mouse splenic lymphocytes.

PubMed

Nitta, T; Konno-Ejiri, H; Nemoto, K; Okumura, S; Ozawa, A; Nakano, M

1986-09-01

Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was mitogenic to murine splenic B lymphocytes, but not T lymphocytes. When murine splenic cells were cultured in the presence of Bu-WSA and concanavalin A (Con A) together, [3H]thymidine uptake of the culture cells synergically increased. The mechanism of the synergy of Con A and Bu-WSA and the participation of interleukin (IL) 1 and 2 in the synergy were studied. The proliferation cells in the synergy were Lyt-1+23- lymphocytes. Ia-positive accessory cells were required for the response. When separated cell populations and Marbrook-type culture vessels were used, a mixed cell population of T lymphocytes and B lymphocytes or macrophages (M phi) produced some active factor(s) after co-stimulation by Con A and Bu-WSA, and the factors enhanced DNA synthesis of another Con A-activated T lymphocyte population. Supernatants obtained from the spleen cell cultures or the mixed cell cultures with T lymphocytes and M phi in the presence of Con A and Bu-WSA contained greater amounts of IL-1 and IL-2 than those from cultures containing Con A or Bu-WSA alone. An addition of exogenous IL-1 or IL-2 to spleen cell cultures with Con A resulted in a proliferative response like that obtained through co-stimulation by Con A and Bu-WSA. These results suggest that the synergistic effect of Con A and Bu-WSA on the proliferative response in murine splenic cells is sustained by the enhancement of production of these T-lymphocyte growth factors.

[Pacifier use: risks and benefits].

PubMed

Martínez Sánchez, L; Díaz González, E; García-Tornel Florensa , S; Gaspà Martí , J

2000-12-01

The use of a dummy as a comforting object in childhood is widespread in civilized societies. The advisability of this practice, as well as the shape, material, or time of use of these objects, is controversial. Data on the possible beneficial effects of these objects are numerous, but there is also a long list of disorders which have been associated with their use. Their soothing effect is the most widely recognized beneficial effect and the possible relationship with a lower incidence of sudden infant death syndrome is the newest. The most important risks of this nonnutritive sucking habit are failure of breastfeeding, dental deformities, recurrent acute otitis media, and the risk of accidents. The development of latex allergy, tooth decay, oral ulcers and sleep disorders are other possible problems. The association with a lower intelligence quotient is disputed. Insufficient data are provided by a review of the pros and the cons of dummy use to encourage or discourage this habit. However, there are sufficient data on which to base firm recommendations such as not starting their use in the first days of life, restricting use after the age of 8 months and withdrawing these objects at the age of 1 year. Pediatricians should be aware of and recommend only dummies that meet safety requirements.

Trends, prospects and challenges in quantifying flow and transport through fractured rocks

NASA Astrophysics Data System (ADS)

Neuman, Shlomo P.

2005-03-01

Among the current problems that hydrogeologists face, perhaps there is none as challenging as the characterization of fractured rock (Faybishenko and Benson 2000). This paper discusses issues associated with the quantification of flow and transport through fractured rocks on scales not exceeding those typically associated with single- and multi-well pressure (or flow) and tracer tests. As much of the corresponding literature has focused on fractured crystalline rocks and hard sedimentary rocks such as sandstones, limestones (karst is excluded) and chalk, so by default does this paper. Direct quantification of flow and transport in such rocks is commonly done on the basis of fracture geometric data coupled with pressure (or flow) and tracer tests, which therefore form the main focus. Geological, geophysical and geochemical (including isotope) data are critical for the qualitative conceptualization of flow and transport in fractured rocks, and are being gradually incorporated in quantitative flow and transport models, in ways that this paper unfortunately cannot describe but in passing. The hydrogeology of fractured aquifers and other earth science aspects of fractured rock hydrology merit separate treatments. All evidence suggests that rarely can one model flow and transport in a fractured rock consistently by treating it as a uniform or mildly nonuniform isotropic continuum. Instead, one must generally account for the highly erratic heterogeneity, directional dependence, dual or multicomponent nature and multiscale behavior of fractured rocks. One way is to depict the rock as a network of discrete fractures (with permeable or impermeable matrix blocks) and another as a nonuniform (single, dual or multiple) continuum. A third way is to combine these into a hybrid model of a nonuniform continuum containing a relatively small number of discrete dominant features. In either case the description can be deterministic or stochastic. The paper contains a brief assessment of these trends in light of recent experimental and theoretical findings, ending with a short list of prospects and challenges for the future. Parmis les problèmes aucquels font face les hydrogéologues, il y a celui de la caractérisation des roches fracturées (Faybishenko and Benson, 2000). Cet article discute des solutions associées aux quantifications des écoulements et des transports à travers les roches fracturées à l'échelles des essais de puits et des essais de traçage. Une part importante de la litérature traite des roches cristallines, des roches sédimentaires consolidées telles les grés, les calcaires (exeptés les karsts) et la craie. De fait, cet article traitera la même panoplie de roches. La quantification directe des écoulements et du transport dans de tels milieux est généralement abordée via la géométrie des fractures, les données de pression et de traçage, qui déslors sont les objets principaux de notre étude. La géologie, la géophysique et la géochimie (incluant la géochimie isotopique) sont criticables car elles donnent des informations qualitatives sur l'écoulement et le transport des aquifères fracturés, et son intégrées graduellement dans des modèles qualitatifs. La manière d'intégrer ces données dépasse malheureusement cet article. L'hydrogéologie des aquifères de fractures et les autres sciences de la terre s'intéressant aux roches fracturées méritent des traîtements différents. En toute évidence il est suggéré que rarement un modèle d'écoulement et de transport dans une roche fracturée puisse être traité comme un milieu isotropique continu, uniforme ou moyennement non-uniforme. Par ailleurs, il est admis la dépendance entre la forte hétérogénéité erratique et la variété de natures et de comportements des roches fracturées. Une manière de régler le problème est de considérer le milieu comme un réseau de fractures discrètes (avec une perméabilité de matrice ou de bloc). Une autre est de l'envisager comme un milieu non-uniforme (simple, double ou multiple) continu. Une troisième manière est de combiner ceci dans un modèle hybride d'un milieu non-uniforme, contenant un relativement petit nombre de fractures dominantes et discrètes. Dans d'auters cas la description peut être déterministe ou stochastique. L'article contient un brève apperçu de ces tendances à la lumière d'expériences récentes et de nouvelles théories, et se termine par une courte liste de «challenge» et de priorités pour le futur. Entre los problemas actuales que enfrentan los hidrogeólogos, quizá no hay uno tan desafiante como la caracterización de roca fracturada (Faybishenko y Benson, 2000). Este artículo discute problemas asociados con la cuantificación de flujo y transporte a través de rocas fracturadas en escalas que no exceden las típicas asociadas con presión (o flujo) en un solo pozo o varios pozos y pruebas con trazadores. Debido a que mucha de la literatura del tema se ha enfocado en rocas cristalinas fracturadas y rocas sedimentarias duras tal como areniscas, calizas (excluyendo karst) y creta, también en contumacia lo hace este artículo. La cuantificación directa del flujo y transporte en tales rocas se hace comúnmente en base a datos geométricos de fracturas acoplados con pruebas de presión (o flujo) y trazadores, los cuales por lo tanto constituyen nuestra principal orientación. Datos geológicos, geofísicos y geoquímicos (incluyendo isótopos) son críticos para la conceptualización cuantitativa de flujo y transporte en rocas fracturadas, y se han estado incorporando gradualmente en modelos cuantitativos de flujo y transporte, en formas que desafortunadamente este artículo solo puede describir de paso. La hidrogeología de rocas fracturadas y otros aspectos de ciencia de la tierra de hidrología de rocas fracturadas amerita tratamientos separados. Toda la evidencia sugiere que uno raramente puede modelizar flujo y transporte en una roca consistentemente fracturada si la considera como una unidad continua isotrópica uniforme o poco uniforme. En vez de adoptar este enfoque, uno tiene generalmente que explicar la heterogeneidad altamente errática, dependencia direccional, naturaleza doble o multicomponente y comportamiento multiescalar de las rocas fracturadas. Una manera de lograr esto consiste en considerar que la roca contiene una redde fracturas discretas (con bloques de matriz permeable o impermeable) y otro modo en considerar la roca como una unidad continua no uniforme (sola, doble o múltiple). Un tercer procedimiento consiste en combinar las dos maneras anteriores en un modelo híbrido el cual consiste de un continuo no uniforme conteniendo un número relativamente pequeño de fracturas principalmente discretas. En ambos casos la descripción puede ser determinística o estocástica. El artículo contiene una evaluación breve de estas tendencias en base a descubrimientos recientes teóricos y experimentales, terminando con una lista corta de prospectos y desafíos para el futuro.

Incentivizing Monitoring and Compliance in Trophy Hunting

PubMed Central

BUNNEFELD, NILS; EDWARDS, CHARLES T T; ATICKEM, ANAGAW; HAILU, FETENE; MILNER-GULLAND, E J

2014-01-01

Conservation scientists are increasingly focusing on the drivers of human behavior and on the implications of various sources of uncertainty for management decision making. Trophy hunting has been suggested as a conservation tool because it gives economic value to wildlife, but recent examples show that overharvesting is a substantial problem and that data limitations are rife. We use a case study of trophy hunting of an endangered antelope, the mountain nyala (Tragelaphus buxtoni), to explore how uncertainties generated by population monitoring and poaching interact with decision making by 2 key stakeholders: the safari companies and the government. We built a management strategy evaluation model that encompasses the population dynamics of mountain nyala, a monitoring model, and a company decision making model. We investigated scenarios of investment into antipoaching and monitoring by governments and safari companies. Harvest strategy was robust to the uncertainty in the population estimates obtained from monitoring, but poaching had a much stronger effect on quota and sustainability. Hence, reducing poaching is in the interests of companies wishing to increase the profitability of their enterprises, for example by engaging community members as game scouts. There is a threshold level of uncertainty in the population estimates beyond which the year-to-year variation in the trophy quota prevented planning by the safari companies. This suggests a role for government in ensuring that a baseline level of population monitoring is carried out such that this level is not exceeded. Our results illustrate the importance of considering the incentives of multiple stakeholders when designing frameworks for resource use and when designing management frameworks to address the particular sources of uncertainty that affect system sustainability most heavily. Incentivando el Monitoreo y el Cumplimiento en la Caza de Trofeos Resumen Científicos conservacionistas cada vez se enfocan más en los conductores del comportamiento humano y en las implicaciones de varias fuentes de incertidumbre en la toma de decisiones de manejo. La cacería de trofeos ha sido sugerida como una herramienta de conservación porque le otorga valor económico a la vida silvestre, pero ejemplos recientes muestran que la sobrecolecta es un problema sustancial y que las limitaciones de datos son abundantes. Usamos el estudio de caso de la cacería de trofeos de un antílope en peligro, el nyala de las montañas (Tragelaphus buxtoni), para explorar como las incertidumbres generadas por el monitoreo de poblaciones y el tráfico de especies interactúan con la toma de decisiones de 2 actores clave: las compañías de safari y el gobierno. Construimos un modelo de evaluación de estrategia de manejo que incluye la dinámica poblacional del nyala de las montañas, un modelo de monitoreo y un modelo de toma de decisiones de una compañía. Investigamos escenarios de inversión en el combate del tráfico de especies y el monitoreo por el gobierno y las compañías de safari. La estrategia de colecta fue robusta hacia la incertidumbre en los estimados de población obtenidos del monitoreo, pero el tráfico de especies tuvo un efecto más fuerte sobre la cuota y la sustentabilidad; por esto, reducir el tráfico de especies está dentro de los intereses de compañías que desean incrementar la rentabilidad de las empresas, por ejemplo al hacer participar a los miembros de la comunidad como guías de caza. Hay un nivel umbral de incertidumbre en los estimados de población más allá del cual la variación anual en la cuota de trofeos previene la planeación por parte de las compañías de safari. Esto sugiere un papel para el gobierno asegurando que un nivel base de monitoreo de población se lleve a cabo para que este nivel no sea excedido. Nuestros resultados ilustran la importancia de considerar los incentivos de partes interesadas múltiples al designar marcos de trabajo para el uso de recursos y que al designar marcos de trabajo de manejo dirigirse a las fuentes particulares de incertidumbre que afecten más al sistema de sustentabilidad. PMID:24001054

Red blood cell dynamics: from cell deformation to ATP release.

PubMed

Wan, Jiandi; Forsyth, Alison M; Stone, Howard A

2011-10-01

The mechanisms of red blood cell (RBC) deformation under both static and dynamic, i.e., flow, conditions have been studied extensively since the mid 1960s. Deformation-induced biochemical reactions and possible signaling in RBCs, however, were proposed only fifteen years ago. Therefore, the fundamental relationship between RBC deformation and cellular signaling dynamics i.e., mechanotransduction, remains incompletely understood. Quantitative understanding of the mechanotransductive pathways in RBCs requires integrative studies of physical models of RBC deformation and cellular biochemical reactions. In this article we review the physical models of RBC deformation, spanning from continuum membrane mechanics to cellular skeleton dynamics under both static and flow conditions, and elaborate the mechanistic links involved in deformation-induced ATP release. This journal is © The Royal Society of Chemistry 2011

Meshless Modeling of Deformable Shapes and their Motion

PubMed Central

Adams, Bart; Ovsjanikov, Maks; Wand, Michael; Seidel, Hans-Peter; Guibas, Leonidas J.

2010-01-01

We present a new framework for interactive shape deformation modeling and key frame interpolation based on a meshless finite element formulation. Starting from a coarse nodal sampling of an object’s volume, we formulate rigidity and volume preservation constraints that are enforced to yield realistic shape deformations at interactive frame rates. Additionally, by specifying key frame poses of the deforming shape and optimizing the nodal displacements while targeting smooth interpolated motion, our algorithm extends to a motion planning framework for deformable objects. This allows reconstructing smooth and plausible deformable shape trajectories in the presence of possibly moving obstacles. The presented results illustrate that our framework can handle complex shapes at interactive rates and hence is a valuable tool for animators to realistically and efficiently model and interpolate deforming 3D shapes. PMID:24839614

Preliminary deformation model for National Seismic Hazard map of Indonesia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meilano, Irwan; Gunawan, Endra; Sarsito, Dina

Preliminary deformation model for the Indonesia’s National Seismic Hazard (NSH) map is constructed as the block rotation and strain accumulation function at the elastic half-space. Deformation due to rigid body motion is estimated by rotating six tectonic blocks in Indonesia. The interseismic deformation due to subduction is estimated by assuming coupling on subduction interface while deformation at active fault is calculated by assuming each of the fault‘s segment slips beneath a locking depth or in combination with creeping in a shallower part. This research shows that rigid body motion dominates the deformation pattern with magnitude more than 15 mm/year, except inmore » the narrow area near subduction zones and active faults where significant deformation reach to 25 mm/year.« less

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Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-20

... and normal definitions Review proposed TOR changes ConUse Review February 7, 2012 ConUse Review... proposed TOR changes and new or modified Sub-groups' roles and responsibilities Decision to release ConUse...] BILLING CODE 4910-13-P ...

Connected vehicle pilot deployment program phase 1, concept of operations (ConOps) - New York City.

DOT National Transportation Integrated Search

2016-04-08

This document describes the Concept of Operations (ConOps) for the New York City Department of Transportation (NYC) Connected Vehicle Pilot Deployment (CVPD) Project. This ConOps describes the current state of operations, establishes the reasons for ...

Increased erythrocyte deformability in fetal erythropoiesis and in erythrocytes deficient in glucose-6-phosphate dehydrogenase and other glycolytic enzymes.

PubMed

Johnson, R M; Panchoosingh, H; Goyette, G; Ravindranath, Y

1999-01-01

Erythrocyte deformability was determined in more than 500 clinical samples, and was found to be elevated in conditions in which fetal-like red cells are produced: aplastic anemia (3/3 cases), myelodysplastic syndromes, polycythemias, sickle cell anemia during treatment with hydroxyurea, paroxysmal nocturnal hemoglobinuria, and recovery from B12 deficiency. Elevated deformability was observed in neonatal erythrocytes, and during recovery from transient erythroblastopenia of childhood, when fetal-like red cells are known to be produced. Increased deformability appears to be a feature of fetal and fetal-like red cells. Forty-eight cases of enzymatically verified glucose-6-phosphate (G-6-PD) deficiency were also examined. Thirty out of 32 G-6-PD(A-) individuals, including both heterozygotes and hemizygotes, exhibited increased deformability during the steady state. In contrast, G-6-PD(Med) hemizygotes had normal deformability. Increased deformability was also found in G-6-PD(Huron) (n=3), G-6-PD(Wayne) (n=4), triose phosphate isomerase deficiency (n=2), and pyruvate kinase deficiency (n=2). An elevated osmoscan was found in more than 90% of female G-6-PD heterozygotes, affording a simple screening test for heterozygotes. Deformability remained high during hemolytic episodes, when older enzyme deficient cells are removed from the circulation. In four cases of G-6-PD deficiency with normal deformability, evidence for co-existing hereditary spherocytosis was found. The combination of conditions with opposing effects on deformability resulted in nearly normal deformability. Because increased red cell deformability is a feature of fetal erythrocytes, these results suggest that the red cells in many cases of glycolytic enzyme deficiency are fetal-like.

The impact of different types of talus deformation after treatment of clubfeet.

PubMed

Kolb, Alexander; Willegger, Madeleine; Schuh, Reinhard; Kaider, Alexandra; Chiari, Catharina; Windhager, Reinhard

2017-01-01

Deformation of the talus in idiopathic congenital clubfeet is a known problem after treatment. However evidence on types of talus deformation and clinical relevance is rare. The aims of this study were first to define different types of talus deformation, and second, to evaluate the impact of these types on long-term results. At a minimum follow-up of ten years 40 idiopathic clubfeet treated by a modified dorsomedial release were analyzed. Based on morphological appearance and the widened range of radius to length ratios (R/L-ratio) in treated clubfeet deformed tali were divided into two groups: tali with decreased R/L-ratios were classified as small-dome talus deformation (SD), tali with increased R/L-ratios were classified as flat-top talus deformation (FT). The impact on degree of arthrosis in the ankle joint, clinical outcome, and ankle range of motion was analyzed. Small-dome talus deformation (SD) was found in nine feet. This group showed decreased R/L-ratios and increased talus opening angles, which were linked to an increased range of motion of the ankle joint (p = 0.033). The impact on onset of arthrosis was not significant for this group (p = 0.056). The group of flat top talus deformation (nine feet) showed increased R/L-ratios and decreased talus opening angles, decreased range of motion (p = 0.019), and a significant impact on onset of arthrosis (p = 0.010). Our study defines a new subgroup of talus deformation: the small dome talus deformation tends to show a better ankle joint range of motion and a lower risk of arthrosis compared to the classical flat dome talus deformation.

Predicting translational deformity following opening-wedge osteotomy for lower limb realignment.

PubMed

Barksfield, Richard C; Monsell, Fergal P

2015-11-01

An opening-wedge osteotomy is well recognised for the management of limb deformity and requires an understanding of the principles of geometry. Translation at the osteotomy is needed when the osteotomy is performed away from the centre of rotation of angulation (CORA), but the amount of translation varies with the distance from the CORA. This translation enables proximal and distal axes on either side of the proposed osteotomy to realign. We have developed two experimental models to establish whether the amount of translation required (based on the translation deformity created) can be predicted based upon simple trigonometry. A predictive algorithm was derived where translational deformity was predicted as 2(tan α × d), where α represents 50 % of the desired angular correction, and d is the distance of the desired osteotomy site from the CORA. A simulated model was developed using TraumaCad online digital software suite (Brainlab AG, Germany). Osteotomies were simulated in the distal femur, proximal tibia and distal tibia for nine sets of lower limb scanograms at incremental distances from the CORA and the resulting translational deformity recorded. There was strong correlation between the distance of the osteotomy from the CORA and simulated translation deformity for distal femoral deformities (correlation coefficient 0.99, p < 0.0001), proximal tibial deformities (correlation coefficient 0.93-0.99, p < 0.0001) and distal tibial deformities (correlation coefficient 0.99, p < 0.0001). There was excellent agreement between the predictive algorithm and simulated translational deformity for all nine simulations (correlation coefficient 0.93-0.99, p < 0.0001). Translational deformity following corrective osteotomy for lower limb deformity can be anticipated and predicted based upon the angular correction and the distance between the planned osteotomy site and the CORA.

Design of protein-responsive micro-sized hydrogels for self-regulating microfluidic systems

NASA Astrophysics Data System (ADS)

Hirayama, Mayu; Tsuruta, Kazuhiro; Kawamura, Akifumi; Ohara, Masayuki; Shoji, Kan; Kawano, Ryuji; Miyata, Takashi

2018-03-01

Diagnosis sensors using micro-total analysis systems (µ-TAS) have been developed for detecting target biomolecules such as proteins and saccharides because they are signal biomolecules for monitoring body conditions and diseases. In this study, biomolecularly stimuli-responsive micro-sized hydrogels that exhibited quick shrinkage in response to lectin concanavalinA (ConA) were prepared in a microchannel by photopolymerization using a fluorescence microscope. In preparing the micro-size hydrogels, glycosyloxyethyl methacrylate (GEMA) as a ligand monomer was copolymerized with a crosslinker in the presence of template ConA in molecular imprinting. The ConA-imprinted micro-hydrogel showed greater shrinkage in response to target ConA than nonimprinted micro-hydrogel. When a buffer solution was switched to an aqueous ConA solution in the Y-shaped microchannel, the flow rates changed quickly because of the responsive shrinkage of the micro-hydrogel prepared in the microchannel. These results suggest that the ConA-imprinted micro-hydrogel acted as a self-regulated microvalve in microfluidic systems.

The SubCons webserver: A user friendly web interface for state-of-the-art subcellular localization prediction.

PubMed

Salvatore, M; Shu, N; Elofsson, A

2018-01-01

SubCons is a recently developed method that predicts the subcellular localization of a protein. It combines predictions from four predictors using a Random Forest classifier. Here, we present the user-friendly web-interface implementation of SubCons. Starting from a protein sequence, the server rapidly predicts the subcellular localizations of an individual protein. In addition, the server accepts the submission of sets of proteins either by uploading the files or programmatically by using command line WSDL API scripts. This makes SubCons ideal for proteome wide analyses allowing the user to scan a whole proteome in few days. From the web page, it is also possible to download precalculated predictions for several eukaryotic organisms. To evaluate the performance of SubCons we present a benchmark of LocTree3 and SubCons using two recent mass-spectrometry based datasets of mouse and drosophila proteins. The server is available at http://subcons.bioinfo.se/. © 2017 The Protein Society.

Positive effects on bone mineralisation and muscular fitness after 10 months of intense school-based physical training for children aged 8–10 years: the FIT FIRST randomised controlled trial

PubMed Central

Larsen, Malte Nejst; Nielsen, Claus Malta; Helge, Eva Wulff; Madsen, Mads; Manniche, Vibeke; Hansen, Lone; Hansen, Peter Riis; Bangsbo, Jens

2018-01-01

Objectives We investigated whether musculoskeletal fitness of school children aged 8–10 years was affected by frequent intense PE sessions. Design and participants 295 Danish school children aged 8–10 years were cluster randomised to a small-sided ball game group (SSG) (n=96, four schools, five classes), a circuit strength training group (CST) (n=83, four schools, four classes) or a control group (CON, n=116, two schools, five classes). Intervention SSG or CST was performed 3×40 min/week over 10 months. Whole-body dual-energy X-ray absorptiometry (DXA) scans were used to determine areal bone mineral density (aBMD), bone mineral content (BMC) and lean body mass (LBM). Flamingo balance, standing long jump and 20-m sprint tests were used to determine muscular fitness. Results Analysis of baseline-to-10 months change scores showed between-group differences in favour of the interventions in whole-body aBMD (SSG vs CON: 8 mg/cm2, 95% CI 3 to 13; CST vs CON: 7 mg/cm2, 95% CI 2 to 13, p<0.05) and leg BMC (SSG vs CON: 11 g, 95% CI 4 to 18; CST vs CON: 11 g, 95% CI 3 to 18, p<0.05). SSG had higher change scores in leg aBMD compared with CON and CST (SSG vs CON: 19 mg/cm2, 95% CI 11 to 39, p<0.05; SSG vs CST: 12 mg/cm2, 95% CI 3 to 21, p<0.05), and CST had higher change scores in whole-body BMC compared with CON (CST vs CON: 25 g, 95% CI 10 to 39, p<0.05). Both training types resulted in higher change scores in postural balance (SSG vs CON: 2.4 fewer falls/min, 95% CI 0.3 to 4.5, CST vs CON: 3.6 fewer falls/min, 95% CI 1.3 to 5.9, p<0.05) and jump length (SSG vs CON: 10%, 95% CI 5 to 16%; CST vs CON: 9%, 95% CI 3 to 15%, p<0.05). No between-group differences were observed for sprint performance or LBM (p>0.05). Conclusions In conclusion, 3×40 min/week with SSG or CST over a full school year improves bone mineralisation and several aspects of muscular fitness of children aged 8–10 years, suggesting that well-organised intense physical education classes can contribute positively to develop musculoskeletal health in young children. Trial registration number NCT02000492, post results. PMID:27297443

Correcting deformity in total knee arthroplasty: Techniques to avoid the release of collateral ligaments in severely deformed knees.

PubMed

Mullaji, A B; Shetty, G M

2016-01-01

Collateral ligament release is advocated in total knee arthroplasty (TKA) to deal with significant coronal plane deformities, but is also associated with significant disadvantages. We describe steps to avoid release of the collateral (superficial medial and lateral collateral) ligaments during TKA in severely deformed knees, while correcting deformity and balancing the knee. ©2016 The British Editorial Society of Bone & Joint Surgery.

A Multivariate Model for Prediction of Obstructive Coronary Disease in Patients with Acute Chest Pain: Development and Validation.

PubMed

Correia, Luis Cláudio Lemos; Cerqueira, Maurício; Carvalhal, Manuela; Ferreira, Felipe; Garcia, Guilherme; Silva, André Barcelos da; Sá, Nicole de; Lopes, Fernanda; Barcelos, Ana Clara; Noya-Rabelo, Márcia

2017-04-01

Currently, there is no validated multivariate model to predict probability of obstructive coronary disease in patients with acute chest pain. To develop and validate a multivariate model to predict coronary artery disease (CAD) based on variables assessed at admission to the coronary care unit (CCU) due to acute chest pain. A total of 470 patients were studied, 370 utilized as the derivation sample and the subsequent 100 patients as the validation sample. As the reference standard, angiography was required to rule in CAD (stenosis ≥ 70%), while either angiography or a negative noninvasive test could be used to rule it out. As predictors, 13 baseline variables related to medical history, 14 characteristics of chest discomfort, and eight variables from physical examination or laboratory tests were tested. The prevalence of CAD was 48%. By logistic regression, six variables remained independent predictors of CAD: age, male gender, relief with nitrate, signs of heart failure, positive electrocardiogram, and troponin. The area under the curve (AUC) of this final model was 0.80 (95% confidence interval [95%CI] = 0.75 - 0.84) in the derivation sample and 0.86 (95%CI = 0.79 - 0.93) in the validation sample. Hosmer-Lemeshow's test indicated good calibration in both samples (p = 0.98 and p = 0.23, respectively). Compared with a basic model containing electrocardiogram and troponin, the full model provided an AUC increment of 0.07 in both derivation (p = 0.0002) and validation (p = 0.039) samples. Integrated discrimination improvement was 0.09 in both derivation (p < 0.001) and validation (p < 0.0015) samples. A multivariate model was derived and validated as an accurate tool for estimating the pretest probability of CAD in patients with acute chest pain. Atualmente, não existe um modelo multivariado validado para predizer a probabilidade de doença coronariana obstrutiva em pacientes com dor torácica aguda. Desenvolver e validar um modelo multivariado para predizer doença arterial coronariana (DAC) com base em variáveis avaliadas à admissão na unidade coronariana (UC) devido a dor torácica aguda. Foram estudados um total de 470 pacientes, 370 utilizados como amostra de derivação e os subsequentes 100 pacientes como amostra de validação. Como padrão de referência, a angiografia foi necessária para descartar DAC (estenose ≥ 70%), enquanto a angiografia ou um teste não invasivo negativo foi utilizado para confirmar a doença. Foram testadas como preditoras 13 variáveis basais relacionadas à história médica, 14 características de desconforto torácico e oito variáveis relacionadas ao exame físico ou testes laboratoriais. A prevalência de DAC foi de 48%. Por regressão logística, seis variáveis permaneceram como preditoras independentes de DAC: idade, gênero masculino, alívio com nitrato, sinais de insuficiência cardíaca, e eletrocardiograma e troponina positivos. A área sob a curva (area under the curve, AUC) deste modelo final foi de 0,80 (intervalo de confiança de 95% [IC95%] = 0,75 - 0,84) na amostra de derivação e 0,86 (IC95% = 0,79 - 0,93) na amostra de validação. O teste de Hosmer-Lemeshow indicou uma boa calibração em ambas as amostras (p = 0,98 e p = 0,23, respectivamente). Em comparação com o modelo básico contendo eletrocardiograma e troponina, o modelo completo ofereceu um incremento na AUC de 0,07 tanto na amostra de derivação (p = 0,0002) quanto na de validação (p = 0,039). A melhoria na discriminação integrada foi de 0,09 nas amostras de derivação (p < 0,001) e validação (p < 0,0015). Um modelo multivariado foi derivado e validado como uma ferramenta acurada para estimar a probabilidade pré-teste de DAC em pacientes com dor torácica aguda.

The relationship between red blood cell deformability metrics and perfusion of an artificial microvascular network

PubMed Central

Sosa, Jose M.; Nielsen, Nathan D.; Vignes, Seth M.; Chen, Tanya G.; Shevkoplyas, Sergey S.

2013-01-01

The ability of red blood cells (RBC) to undergo a wide range of deformations while traversing the microvasculature is crucial for adequate perfusion. Interpretation of RBC deformability measurements performed in vitro in the context of microvascular perfusion has been notoriously difficult. This study compares the measurements of RBC deformability performed using micropore filtration and ektacytometry with the RBC ability to perfuse an artificial microvascular network (AMVN). Human RBCs were collected from healthy consenting volunteers, leukoreduced, washed and exposed to graded concentrations (0% – 0.08%) of glutaraldehyde (a non-specific protein cross-linker) and diamide (a spectrin-specific protein cross-linker) to impair the deformability of RBCs. Samples comprising cells with two different levels of deformability were created by adding non-deformable RBCs (hardened by exposure to 0.08% glutaraldehyde) to the sample of normal healthy RBCs. Ektacytometry indicated a nearly linear decline in RBC deformability with increasing glutaraldehyde concentration. Micropore filtration showed a significant reduction only for concentrations of glutaraldehyde higher than 0.04%. Neither micropore filtration nor ektacytometry measurements could accurately predict the AMVN perfusion. Treatment with diamide reduced RBC deformability as indicated by ektacytometry, but had no significant effect on either micropore filtration or the AMVN perfusion. Both micropore filtration and ektacytometry showed a linear decline in effective RBC deformability with increasing fraction of non-deformable RBCs in the sample. The corresponding decline in the AMVN perfusion plateaued above 50%, reflecting the innate ability of blood flow in the microvasculature to bypass occluded capillaries. Our results suggest that in vitro measurements of RBC deformability performed using either micropore filtration or ektacytometry may not represent the ability of same RBCs to perfuse microvascular networks. Further development of biomimetic tools for measuring RBC deformability (e.g. the AMVN) could enable a more functionally relevant testing of RBC mechanical properties. PMID:23603326

The relationship between red blood cell deformability metrics and perfusion of an artificial microvascular network.

PubMed

Sosa, Jose M; Nielsen, Nathan D; Vignes, Seth M; Chen, Tanya G; Shevkoplyas, Sergey S

2014-01-01

The ability of red blood cells (RBC) to undergo a wide range of deformations while traversing the microvasculature is crucial for adequate perfusion. Interpretation of RBC deformability measurements performed in vitro in the context of microvascular perfusion has been notoriously difficult. This study compares the measurements of RBC deformability performed using micropore filtration and ektacytometry with the RBC ability to perfuse an artificial microvascular network (AMVN). Human RBCs were collected from healthy consenting volunteers, leukoreduced, washed and exposed to graded concentrations (0-0.08%) of glutaraldehyde (a non-specific protein cross-linker) and diamide (a spectrin-specific protein cross-linker) to impair the deformability of RBCs. Samples comprising cells with two different levels of deformability were created by adding non-deformable RBCs (hardened by exposure to 0.08% glutaraldehyde) to the sample of normal healthy RBCs. Ektacytometry indicated a nearly linear decline in RBC deformability with increasing glutaraldehyde concentration. Micropore filtration showed a significant reduction only for concentrations of glutaraldehyde higher than 0.04%. Neither micropore filtration nor ektacytometry measurements could accurately predict the AMVN perfusion. Treatment with diamide reduced RBC deformability as indicated by ektacytometry, but had no significant effect on either micropore filtration or the AMVN perfusion. Both micropore filtration and ektacytometry showed a linear decline in effective RBC deformability with increasing fraction of non-deformable RBCs in the sample. The corresponding decline in the AMVN perfusion plateaued above 50%, reflecting the innate ability of blood flow in the microvasculature to bypass occluded capillaries. Our results suggest that in vitro measurements of RBC deformability performed using either micropore filtration or ektacytometry may not represent the ability of same RBCs to perfuse microvascular networks. Further development of biomimetic tools for measuring RBC deformability (e.g. the AMVN) could enable a more functionally relevant testing of RBC mechanical properties.

A q-deformation of the Bogoliubov transformations

NASA Astrophysics Data System (ADS)

Arraut, Ivan; Segovia, Carlos

2018-02-01

An approach for q-deformed Bogoliubov transformations is presented. Assuming a left-right module action together with an *-operation and deformed commutation relations, we construct a q-deformation of the nonlinear Bogoliubov transformation. Finally, we introduce a Hopf structure when q is a root of unity.

Paleoneurosurgical aspects of Proto-Bulgarian artificial skull deformations.

PubMed

Enchev, Yavor; Nedelkov, Grigoriy; Atanassova-Timeva, Nadezhda; Jordanov, Jordan

2010-12-01

Paleoneurosurgery represents a comparatively new developing direction of neurosurgery dealing with archaeological skull and spine finds and studying their neurosurgical aspects. Artificial skull deformation, as a bone artifact, naturally has been one of the main paleoneurosurgical research topics. Traditionally, the relevant neurosurgical literature has analyzed in detail the intentional skull deformations in South America's tribes. However, little is known about the artificial skull deformations of the Proto-Bulgarians, and what information exists is mostly due to anthropological studies. The Proto-Bulgarians originated from Central Asia, and distributed their skull deformation ritual on the Balkan Peninsula by their migration and domination. Proto-Bulgarian artificial skull deformation was an erect or oblique form of the anular type, and was achieved by 1 or 2 pressure bandages that were tightened around a newborn's head for a sufficiently long period. The intentional skull deformation in Proto-Bulgarians was not associated with neurological deficits and/or mental retardation. No indirect signs of chronic elevated intracranial pressure were found on the 3D CT reconstruction of the artificially deformed skulls.

Deformation compatibility in a single crystalline Ni superalloy

PubMed Central

Zhang, Tiantian; Dunne, Fionn P. E.

2016-01-01

Deformation in materials is often complex and requires rigorous understanding to predict engineering component lifetime. Experimental understanding of deformation requires utilization of advanced characterization techniques, such as high spatial resolution digital image correlation (HR-DIC) and high angular resolution electron backscatter diffraction (HR-EBSD), combined with clear interpretation of their results to understand how a material has deformed. In this study, we use HR-DIC and HR-EBSD to explore the mechanical behaviour of a single-crystal nickel alloy and to highlight opportunities to understand the complete deformations state in materials. Coupling of HR-DIC and HR-EBSD enables us to precisely focus on the extent which we can access the deformation gradient, F, in its entirety and uncouple contributions from elastic deformation gradients, slip and rigid body rotations. Our results show a clear demonstration of the capabilities of these techniques, found within our experimental toolbox, to underpin fundamental mechanistic studies of deformation in polycrystalline materials and the role of microstructure. PMID:26997901

Nasal septal deformities in ear, nose, and throat patients: an international study.

PubMed

Mladina, Ranko; Cujić, Emil; Subarić, Marin; Vuković, Katarina

2008-01-01

The purpose of this study was to investigate the incidence and characteristics of nasal septum deformities in ear, nose, and throat (ENT) patients in various geographic regions in the world. Anterior rhinoscopy without nasal decongestion was performed in 17 ENT centers in 14 countries. The septal deformities were classified according to the classification system proposed by Mladina. A total of 2589 adult ENT patients (1500 males and 1089 females) were examined. Septal deformities were found in 89.2% of subjects. Left-sided deformities were slightly more prevalent than right-sided deformities (51.6% and 48.4%, respectively). The most frequent type of deformity was type 3 (20.4%). Straight septum was found in 15.4% of females and 7.5% of males. Almost 90% of the subjects showed 1 of the 7 types of septal deformity. There were no statistically significant differences in the incidence of their appearance among particular geographic regions. Type 3 was the most frequent type. Straight septum was twice as frequent in females than in males.

Non-affine deformations in polymer hydrogels

PubMed Central

Wen, Qi; Basu, Anindita; Janmey, Paul A.; Yodh, A. G.

2012-01-01

Most theories of soft matter elasticity assume that the local strain in a sample after deformation is identical everywhere and equal to the macroscopic strain, or equivalently that the deformation is affine. We discuss the elasticity of hydrogels of crosslinked polymers with special attention to affine and non-affine theories of elasticity. Experimental procedures to measure non-affine deformations are also described. Entropic theories, which account for gel elasticity based on stretching out individual polymer chains, predict affine deformations. In contrast, simulations of network deformation that result in bending of the stiff constituent filaments generally predict non-affine behavior. Results from experiments show significant non-affine deformation in hydrogels even when they are formed by flexible polymers for which bending would appear to be negligible compared to stretching. However, this finding is not necessarily an experimental proof of the non-affine model for elasticity. We emphasize the insights gained from experiments using confocal rheoscope and show that, in addition to filament bending, sample micro-inhomogeneity can be a significant alternative source of non-affine deformation. PMID:23002395

Hippo/crates-in-situ deformation strain and testure studies using neutron time-of-flight diffraction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vogel, S. C.; Hartig, C.; Brissier, T. D.

2005-01-01

In situ deformation studies by diffraction allow studying of deformation mechanisms and provide valuable data to validate and improve deformation models. In particular, deformation studies using time-of-flight neutrons provide averages over large numbers of grains and allow to probing the response of lattice planes parallel and perpendicular to the applied load simultaneously. In this paper we describe the load-frame CRATES, designed for the HIPPO neutron time-of-flight diffractometer at LANSCE. The HIPPO/CRATES combination allows probing up to 20 diffraction vectors simultaneously and provides rotation of the sample in the beam while under load. With this, deformation texture, i.e. the change ofmore » grain orientation due to plastic deformation, or strain pole figures may be measured. We report initial results of a validation experiment, comparing deformation of a Zircaloy specimen measured using the NPD neutron diffractometer with results obtained for the same material using HIPPO/CRATES.« less

Effects of hot compression deformation temperature on the microstructure and properties of Al-Zr-La alloys

NASA Astrophysics Data System (ADS)

Yue, Xian-hua; Liu, Chun-fang; Liu, Hui-hua; Xiao, Su-fen; Tang, Zheng-hua; Tang, Tian

2018-02-01

The main goal of this study is to investigate the microstructure and electrical properties of Al-Zr-La alloys under different hot compression deformation temperatures. In particular, a Gleeble 3500 thermal simulator was used to carry out multi-pass hot compression tests. For five-pass hot compression deformation, the last-pass deformation temperatures were 240, 260, 300, 340, 380, and 420°C, respectively, where the first-pass deformation temperature was 460°C. The experimental results indicated that increasing the hot compression deformation temperature with each pass resulted in improved electrical conductivity of the alloy. Consequently, the flow stress was reduced after deformation of the samples subjected to the same number of passes. In addition, the dislocation density gradually decreased and the grain size increased after hot compression deformation. Furthermore, the dynamic recrystallization behavior was effectively suppressed during the hot compression process because spherical Al3Zr precipitates pinned the dislocation movement effectively and prevented grain boundary sliding.

Sessile dislocations by reactions in NiAl severely deformed at room temperature

DOE PAGES

Geist, D.; Gammer, C.; Rentenberger, C.; ...

2015-02-05

B2 ordered NiAl is known for its poor room temperature (RT) ductility; failure occurs in a brittle like manner even in ductile single crystals deforming by single slip. In the present study NiAl was severely deformed at RT using the method of high pressure torsion (HPT) enabling the hitherto impossible investigation of multiple slip deformation. Methods of transmission electron microscopy were used to analyze the dislocations formed by the plastic deformation showing that as expected dislocations with Burgers vector a(100) carry the plasticity during HPT deformation at RT. In addition, we observe that they often form a(110) dislocations by dislocationmore » reactions; the a(110) dislocations are considered to be sessile based on calculations found in the literature. It is therefore concluded that the frequently encountered 3D dislocation networks containing sessile a(110) dislocations are pinned and lead to deformation-induced embrittlement. In spite of the severe deformation, the chemical order remains unchanged.« less

ChainMail based neural dynamics modeling of soft tissue deformation for surgical simulation.

PubMed

Zhang, Jinao; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

2017-07-20

Realistic and real-time modeling and simulation of soft tissue deformation is a fundamental research issue in the field of surgical simulation. In this paper, a novel cellular neural network approach is presented for modeling and simulation of soft tissue deformation by combining neural dynamics of cellular neural network with ChainMail mechanism. The proposed method formulates the problem of elastic deformation into cellular neural network activities to avoid the complex computation of elasticity. The local position adjustments of ChainMail are incorporated into the cellular neural network as the local connectivity of cells, through which the dynamic behaviors of soft tissue deformation are transformed into the neural dynamics of cellular neural network. Experiments demonstrate that the proposed neural network approach is capable of modeling the soft tissues' nonlinear deformation and typical mechanical behaviors. The proposed method not only improves ChainMail's linear deformation with the nonlinear characteristics of neural dynamics but also enables the cellular neural network to follow the principle of continuum mechanics to simulate soft tissue deformation.

Investigation of the effects of aeroelastic deformations on the radar cross section of aircraft

NASA Astrophysics Data System (ADS)

McKenzie, Samuel D.

1991-12-01

The effects of aeroelastic deformations on the radar cross section (RCS) of a T-38 trainer jet and a C-5A transport aircraft are examined and characterized. Realistic representations of structural wing deformations are obtained from a mechanical/computer aided design software package called NASTRAN. NASTRAN is used to evaluate the structural parameters of the aircraft as well as the restraints and loads associated with realistic flight conditions. Geometries for both the non-deformed and deformed airframes are obtained from the NASTRAN models and translated into RCS models. The RCS is analyzed using a numerical modeling code called the Radar Cross Section - Basic Scattering Code, version 2 which was developed at the Ohio State University and is based on the uniform geometric theory of diffraction. The code is used to analyze the effects of aeroelastic deformations on the RCS of the aircraft by comparing the computed RCS representing the deformed airframe to that of the non-deformed airframe and characterizing the differences between them.

Determination of accuracy of winding deformation method using kNN based classifier used for 3 MVA transformer

NASA Astrophysics Data System (ADS)

Ahmed, Mustafa Wasir; Baishya, Manash Jyoti; Sharma, Sasanka Sekhor; Hazarika, Manash

2018-04-01

This paper presents a detecting system on power transformer in transformer winding, core and on load tap changer (OLTC). Accuracy of winding deformation is determined using kNN based classifier. Winding deformation in power transformer can be measured using sweep frequency response analysis (SFRA), which can enhance the diagnosis accuracy to a large degree. It is suggested that in the results minor deformation faults can be detected at frequency range of 1 mHz to 2 MHz. The values of RCL parameters are changed when faults occur and hence frequency response of the winding will change accordingly. The SFRA data of tested transformer is compared with reference trace. The difference between two graphs indicate faults in the transformer. The deformation between 1 mHz to 1kHz gives winding deformation, 1 kHz to 100 kHz gives core deformation and 100 kHz to 2 MHz gives OLTC deformation.

Hot compression deformation behavior of AISI 321 austenitic stainless steel

NASA Astrophysics Data System (ADS)

Haj, Mehdi; Mansouri, Hojjatollah; Vafaei, Reza; Ebrahimi, Golam Reza; Kanani, Ali

2013-06-01

The hot compression behavior of AISI 321 austenitic stainless steel was studied at the temperatures of 950-1100°C and the strain rates of 0.01-1 s-1 using a Baehr DIL-805 deformation dilatometer. The hot deformation equations and the relationship between hot deformation parameters were obtained. It is found that strain rate and deformation temperature significantly influence the flow stress behavior of the steel. The work hardening rate and the peak value of flow stress increase with the decrease of deformation temperature and the increase of strain rate. In addition, the activation energy of deformation ( Q) is calculated as 433.343 kJ/mol. The microstructural evolution during deformation indicates that, at the temperature of 950°C and the strain rate of 0.01 s-1, small circle-like precipitates form along grain boundaries; but at the temperatures above 950°C, the dissolution of such precipitates occurs. Energy-dispersive X-ray analyses indicate that the precipitates are complex carbides of Cr, Fe, Mn, Ni, and Ti.

Helium release during shale deformation: Experimental validation

DOE PAGES

Bauer, Stephen J.; Gardner, W. Payton; Heath, Jason E.

2016-07-01

This paper describes initial experimental results of helium tracer release monitoring during deformation of shale. Naturally occurring radiogenic 4He is present in high concentration in most shales. During rock deformation, accumulated helium could be released as fractures are created and new transport pathways are created. We present the results of an experimental study in which confined reservoir shale samples, cored parallel and perpendicular to bedding, which were initially saturated with helium to simulate reservoir conditions, are subjected to triaxial compressive deformation. During the deformation experiment, differential stress, axial, and radial strains are systematically tracked. Release of helium is dynamically measuredmore » using a helium mass spectrometer leak detector. Helium released during deformation is observable at the laboratory scale and the release is tightly coupled to the shale deformation. These first measurements of dynamic helium release from rocks undergoing deformation show that helium provides information on the evolution of microstructure as a function of changes in stress and strain.« less

Mechanical Behavior and Microstructure Evolution of Bearing Steel 52100 During Warm Compression

NASA Astrophysics Data System (ADS)

Huo, Yuanming; He, Tao; Chen, Shoushuang; Wu, Riming

2018-05-01

High-performance bearing steel requires a fine and homogeneous structure of carbide particles. Direct deformation spheroidizing of bearing steel in a dual-phase zone can contribute to achieving this important structure. In this work, warm compression testing of 52100 bearing steel was performed at temperatures in the range of 650-850°C and at strain rates of 0.1-10.0 s-1. The effect of deformation temperatures on mechanical behavior and microstructure evolution was investigated to determine the warm deformation temperature window. The effect of deformation rates on microstructure evolution and metal flow softening behavior of the warm compression was analyzed and discussed. Experimental results showed that the temperature range from 750°C to 800°C should be regarded as the critical range separating warm and hot deformation. Warm deformation at temperatures in the range of 650-750°C promoted carbide spheroidization, and this was determined to be the warm deformation temperature window. Metal flow softening during the warm deformation was caused by carbide spheroidization.

SU-F-I-51: CT/MR Image Deformation: The Clinical Assessment QA in Target Delineation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, C; Chen, Y

Purpose: To study the deformation effects in CT/MR image registration of head and neck (HN) cancers. We present a clinical indication in guiding and simplifying registration procedures of this process while CT images possessed artifacts. Methods: CT/MR image fusion provides better soft tissue contrast in intracranial GTV definition with artifacts. However, whether the fusion process should include the deformation process is questionable and not recommended. We performed CT/MR image registration of a HN patient with tonsil GTV and nodes delineation on Varian Velocity™ system. Both rigid transformation and deformable registration of the same CT/MR imaging data were processed separately. Physician’smore » selection of target delineation was implemented to identify the variations. Transformation matrix was shown with visual identification, as well as the deformation QA numbers and figures were assessed. Results: The deformable CT/MR images were traced with the calculated matrix, both translation and rotational parameters were summarized. In deformable quality QA, the calculated Jacobian matrix was analyzed, which the min/mean/max of 0.73/0/99/1.37, respectively. Jacobian matrix of right neck node was 0.84/1.13/1.41, which present dis-similarity of the nodal area. If Jacobian = 1, the deformation is at the optimum situation. In this case, the deformation results have shown better target delineation for CT/MR deformation than rigid transformation. Though the root-mean-square vector difference is 1.48 mm, with similar rotational components, the cord and vertebrae position were aligned much better in the deformable MR images than the rigid transformation. Conclusion: CT/MR with/without image deformation presents similar image registration matrix; there were significant differentiate the anatomical structures in the region of interest by deformable process. Though vendor suggested only rigid transformation between CT/MR assuming the geometry remain similar, our findings indicated with patient positional variations, deformation registration is needed to generate proper GTV coverage, which will be irradiated more accurately in the following boost phase.« less

Deformation rates across the San Andreas Fault system, central California determined by geology and geodesy

NASA Astrophysics Data System (ADS)

Titus, Sarah J.

The San Andreas fault system is a transpressional plate boundary characterized by sub-parallel dextral strike-slip faults separating internally deformed crustal blocks in central California. Both geodetic and geologic tools were used to understand the short- and long-term partitioning of deformation in both the crust and the lithospheric mantle across the plate boundary system. GPS data indicate that the short-term discrete deformation rate is ˜28 mm/yr for the central creeping segment of the San Andreas fault and increases to 33 mm/yr at +/-35 km from the fault. This gradient in deformation rates is interpreted to reflect elastic locking of the creeping segment at depth, distributed off-fault deformation, or some combination of these two mechanisms. These short-term fault-parallel deformation rates are slower than the expected geologic slip rate and the relative plate motion rate. Structural analysis of folds and transpressional kinematic modeling were used to quantify long-term distributed deformation adjacent to the Rinconada fault. Folding accommodates approximately 5 km of wrench deformation, which translates to a deformation rate of ˜1 mm/yr since the start of the Pliocene. Integration with discrete offset on the Rinconada fault indicates that this portion of the San Andreas fault system is approximately 80% strike-slip partitioned. This kinematic fold model can be applied to the entire San Andreas fault system and may explain some of the across-fault gradient in deformation rates recorded by the geodetic data. Petrologic examination of mantle xenoliths from the Coyote Lake basalt near the Calaveras fault was used to link crustal plate boundary deformation at the surface with models for the accommodation of deformation in the lithospheric mantle. Seismic anisotropy calculations based on xenolith petrofabrics suggest that an anisotropic mantle layer thickness of 35-85 km is required to explain the observed shear wave splitting delay times in central California. The available data are most consistent with models for a broad zone of distributed deformation in the lithospheric mantle.

Structural defects in natural plastically deformed diamonds: Evidence from EPR spectroscopy

NASA Astrophysics Data System (ADS)

Mineeva, R. M.; Titkov, S. V.; Speransky, A. V.

2009-06-01

Structural defects formed as a result of plastic deformation in natural diamond crystals have been studied by EPR spectroscopy. The spectra of brown, pink-brown, black-brown, pink-purple, and gray plastically deformed diamonds of type Ia from deposits in Yakutia and the Urals were recorded. The results of EPR spectroscopy allowed us to identify various deformation centers in the structure of natural diamonds and to show that nitrogen centers were transformed under epigenetic mechanical loading. Abundant A centers, consisting of two isomorphic nitrogen atoms located in neighboring structural sites, were destroyed as a result of this process to form a series of N1, N4, W7, M2, and M3 nitrogen centers. Such centers are characterized by an anisotropic spatial distribution and a positive charge, related to the mechanism of their formation. In addition, N2 centers (probably, deformation-produced dislocations decorated by nitrogen) were formed in all plastically deformed diamonds and W10 and W35 centers (the models have not been finally ascertained) were formed in some of them. It has been established that diamonds with various types of deformation-induced color contain characteristic associations of these deformation centers. The diversity of associations of deformation centers indicates appreciable variations in conditions of disintegration of deep-seated rocks, transfer of diamonds to the Earth’s surface, and formation of kimberlitic deposits. Depending on the conditions of mechanical loading, the diamond crystals were plastically deformed by either dislocation gliding or mechanical twinning. Characteristic features of plastic deformation by dislocation gliding are the substantial prevalence of the N2 centers over other deformation centers and the occurrence of the high-spin W10 and W35 centers. The attributes of less frequent plastic deformation by mechanical twinning are unusual localization of the M2 centers and, in some cases, the N1 centers in microtwinned lamellae. Numerous data on models of deformation centers in natural diamonds, including the M2 and M3 centers, which were observed in the studied collection for the first time, are discussed.

Meeting Report: Breath Biomarkers Networking Sessions at PittCon 2010, Orlando, Florida

EPA Science Inventory

The Pittsburgh Conference and Exposition, or "PittCon" (www.pittcon.org/), is one of the largest international conferences for analytical chemistry and instrumentation typically attracting about 25,000 attendees and 1,000 commercial exhibitors. PittCon began in 1950 as a small sp...

Breath Analysis Science at PittCon 2012, Orlando, Florida

EPA Science Inventory

Breath analysis science was featured in three organized sessions at this year’s Pittsburgh Conference and Exposition, or ‘PittCon 2012’ (http://www.pittcon.org/). As described in previous meeting reports, PittCon is one of the largest international conferences for analytical chem...

48 CFR 301.608 - Training requirements for purchase cardholders, Approving Officials, and Agency/Organization...

Code of Federal Regulations, 2013 CFR

2013-10-01

... REGULATION SYSTEM Career Development, Contracting Authority, and Responsibilities 301.608 Training... Arrangements). • CON 110 (Mission Support Planning). Purchase cardholders and Approving Officials Yearly... appropriations law. • CON 100 (Shaping Smart Business Arrangements). • CON 110 (Mission Support Planning). Agency...

48 CFR 301.608 - Training requirements for purchase cardholders, Approving Officials, and Agency/Organization...

Code of Federal Regulations, 2014 CFR

2014-10-01

... REGULATION SYSTEM Career Development, Contracting Authority, and Responsibilities 301.608 Training... Arrangements). • CON 110 (Mission Support Planning). Purchase cardholders and Approving Officials Yearly... appropriations law. • CON 100 (Shaping Smart Business Arrangements). • CON 110 (Mission Support Planning). Agency...

Alterations in Hepatic FGF21, Co-Regulated Genes, and Upstream Metabolic Genes in Response to Nutrition, Ketosis and Inflammation in Peripartal Holstein Cows

PubMed Central

Akbar, Haji; Batistel, Fernanda; Drackley, James K.; Loor, Juan J.

2015-01-01

In rodents, fibroblast growth factor 21 (FGF21) has emerged as a key metabolic regulator produced by liver. To gather preliminary data on the potential importance of FGF1, co-regulated genes, and upstream metabolic genes, we examined the hepatic mRNA expression in response to nutrition and inflammation in dairy cows. In experiment 1, induction of ketosis through feed restriction on d 5 postpartum upregulated FGF21, its co-receptor KLB, and PPARA but only elicited a numerical increase in serum FGF21 concentration. In experiment 2, cows in control (CON) or receiving 50 g/d of L-carnitine (C50) from -14 through 21 d had increased FGF21, PPARA, and NFIL3 on d 10 compared with d 2 postpartum. In contrast, compared with CON and C50, 100 g/d L-carnitine (C100) resulted in lower FGF21, KLB, ANGPTL4, and ARNTL expression on d 10. In experiment 3, cows were fed during the dry period either a higher-energy (OVE; 1.62 Mcal/kg DM) or lower-energy (CON; 1.34 Mcal/kg DM) diet and received 0 (OVE:N, CON:N) or 200 μg of LPS (OVE:Y, CON:Y) into the mammary gland at d 7 postpartum. For FGF21 mRNA expression in CON, the LPS challenge (CON:Y) prevented a decrease in expression between d 7 and 14 postpartum such that cows in CON:N had a 4-fold lower expression on d 14 compared with d 7. The inflammatory stimulus induced by LPS in CON:Y resulted in upregulation of PPARA on d 14 to a similar level as cows in OVE:N. In OVE:Y, expression of PPARA was lower than CON:N on d 7 and remained unchanged on d 14. On d 7, LPS led to a 4-fold greater serum FGF21 only in OVE but not in CON cows. In fact, OVE:Y reached the same serum FGF21 concentration as CON:N, suggesting a carryover effect of dietary energy level on signaling mechanisms within liver. Overall, results indicate that nutrition, ketosis, and inflammation during the peripartal period can alter hepatic FGF21, co-regulated genes, and upstream metabolic genes to various extents. The functional outcome of these changes merits further study, and in particular the mechanisms regulating transcription in response to changes in energy balance and feed intake. PMID:26451842

Alterations in Hepatic FGF21, Co-Regulated Genes, and Upstream Metabolic Genes in Response to Nutrition, Ketosis and Inflammation in Peripartal Holstein Cows.

PubMed

Akbar, Haji; Batistel, Fernanda; Drackley, James K; Loor, Juan J

2015-01-01

In rodents, fibroblast growth factor 21 (FGF21) has emerged as a key metabolic regulator produced by liver. To gather preliminary data on the potential importance of FGF1, co-regulated genes, and upstream metabolic genes, we examined the hepatic mRNA expression in response to nutrition and inflammation in dairy cows. In experiment 1, induction of ketosis through feed restriction on d 5 postpartum upregulated FGF21, its co-receptor KLB, and PPARA but only elicited a numerical increase in serum FGF21 concentration. In experiment 2, cows in control (CON) or receiving 50 g/d of L-carnitine (C50) from -14 through 21 d had increased FGF21, PPARA, and NFIL3 on d 10 compared with d 2 postpartum. In contrast, compared with CON and C50, 100 g/d L-carnitine (C100) resulted in lower FGF21, KLB, ANGPTL4, and ARNTL expression on d 10. In experiment 3, cows were fed during the dry period either a higher-energy (OVE; 1.62 Mcal/kg DM) or lower-energy (CON; 1.34 Mcal/kg DM) diet and received 0 (OVE:N, CON:N) or 200 μg of LPS (OVE:Y, CON:Y) into the mammary gland at d 7 postpartum. For FGF21 mRNA expression in CON, the LPS challenge (CON:Y) prevented a decrease in expression between d 7 and 14 postpartum such that cows in CON:N had a 4-fold lower expression on d 14 compared with d 7. The inflammatory stimulus induced by LPS in CON:Y resulted in upregulation of PPARA on d 14 to a similar level as cows in OVE:N. In OVE:Y, expression of PPARA was lower than CON:N on d 7 and remained unchanged on d 14. On d 7, LPS led to a 4-fold greater serum FGF21 only in OVE but not in CON cows. In fact, OVE:Y reached the same serum FGF21 concentration as CON:N, suggesting a carryover effect of dietary energy level on signaling mechanisms within liver. Overall, results indicate that nutrition, ketosis, and inflammation during the peripartal period can alter hepatic FGF21, co-regulated genes, and upstream metabolic genes to various extents. The functional outcome of these changes merits further study, and in particular the mechanisms regulating transcription in response to changes in energy balance and feed intake.

In situ spectroscopic study of the plastic deformation of amorphous silicon under nonhydrostatic conditions induced by indentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gerbig, Yvonne B.; Michaels, C. A.; Bradby, Jodie E.

Indentation-induced plastic deformation of amorphous silicon (a-Si) thin films was studied by in situ Raman imaging of the deformed contact region of an indented sample, employing a Raman spectroscopy-enhanced instrumented indentation technique (IIT). The occurrence and evolving spatial distribution of changes in the a-Si structure caused by processes, such as polyamorphization and crystallization, induced by indentation loading were observed. Furthermore, the obtained experimental results are linked with previously published work on the plastic deformation of a-Si under hydrostatic compression and shear deformation to establish a model for the deformation behavior of a-Si under indentation loading.

Instrumentation and fusion for congenital spine deformities.

PubMed

Hedequist, Daniel J

2009-08-01

A retrospective clinical review. To review the use of modern instrumentation of the spine for congenital spinal deformities. Spinal instrumentation has evolved since the advent of the Harrington rod. There is a paucity of literature, which discusses the use of modern spinal instrumentation in congenital spine deformity cases. This review focuses on modern instrumentation techniques for congenital scoliosis and kyphosis. A systematic review was performed of the literature to discuss spinal implant use for congenital deformities. Spinal instrumentation may be safely and effectively used in cases of congenital spinal deformity. Spinal surgeons taking care of children with congenital spine deformities need to be trained in all aspects of modern spinal instrumentation.

Nuclear Deformation at Finite Temperature

NASA Astrophysics Data System (ADS)

Alhassid, Y.; Gilbreth, C. N.; Bertsch, G. F.

2014-12-01

Deformation, a key concept in our understanding of heavy nuclei, is based on a mean-field description that breaks the rotational invariance of the nuclear many-body Hamiltonian. We present a method to analyze nuclear deformations at finite temperature in a framework that preserves rotational invariance. The auxiliary-field Monte Carlo method is used to generate a statistical ensemble and calculate the probability distribution associated with the quadrupole operator. Applying the technique to nuclei in the rare-earth region, we identify model-independent signatures of deformation and find that deformation effects persist to temperatures higher than the spherical-to-deformed shape phase-transition temperature of mean-field theory.

Accidental degeneracies in nonlinear quantum deformed systems

NASA Astrophysics Data System (ADS)

Aleixo, A. N. F.; Balantekin, A. B.

2011-09-01

We construct a multi-parameter nonlinear deformed algebra for quantum confined systems that includes many other deformed models as particular cases. We demonstrate that such systems exhibit the property of accidental pairwise energy level degeneracies. We also study, as a special case of our multi-parameter deformation formalism, the extension of the Tamm-Dancoff cutoff deformed oscillator and the occurrence of accidental pairwise degeneracy in the energy levels of the deformed system. As an application, we discuss the case of a trigonometric Rosen-Morse potential, which is successfully used in models for quantum confined systems, ranging from electrons in quantum dots to quarks in hadrons.

In situ spectroscopic study of the plastic deformation of amorphous silicon under nonhydrostatic conditions induced by indentation

DOE PAGES

Gerbig, Yvonne B.; Michaels, C. A.; Bradby, Jodie E.; ...

2015-12-17

Indentation-induced plastic deformation of amorphous silicon (a-Si) thin films was studied by in situ Raman imaging of the deformed contact region of an indented sample, employing a Raman spectroscopy-enhanced instrumented indentation technique (IIT). The occurrence and evolving spatial distribution of changes in the a-Si structure caused by processes, such as polyamorphization and crystallization, induced by indentation loading were observed. Furthermore, the obtained experimental results are linked with previously published work on the plastic deformation of a-Si under hydrostatic compression and shear deformation to establish a model for the deformation behavior of a-Si under indentation loading.

Morphological Deformities as Biomarkers in Fish from Contaminated Rivers in Taiwan

PubMed Central

Sun, Peter Lin; Hawkins, William E.; Overstreet, Robin M.; Brown-Peterson, Nancy J.

2009-01-01

Tilapia (Oreochromis spp.) were collected seasonally from four contaminated rivers in southwestern Taiwan for studies of morphological deformities that could be used as biomarkers of contamination. Morphological deformities found in tilapia were separated into 15 categories. Overall, the prevalence of deformities such as split fins, lower lip extension and gill deformities were significantly related to various water quality parameters, including low DO and high ammonium, lead and zinc concentrations. The persistence of tilapia in polluted waters and the development of a suite of morphological deformities suggest that tilapia can be used as sentinels of non-point source pollution in rivers. PMID:19742162

Effect of Deformation Parameters on Microstructure and Properties During DIFT of X70HD Pipeline Steel

NASA Astrophysics Data System (ADS)

Wang, Jian; Zhu, Wei; Xiao, Hong; Zhang, Liang-liang; Qin, Hao; Yu, Yue

2018-02-01

Grain refinement is a critical approach to improve the strength of materials without damaging the toughness. The grains of deformation-induced ferrite are considerably smaller than those of proeutectoid ferrite. Grain refinement is crucial to the application of deformation-induced ferrite. The composition of ferrite and bainite or martensite is important in controlling the performance of X70HD pipeline steel, and cooling significantly influences the control of their ratio and grain size. By analyzing the static and dynamic phase-transition points using Gleeble-3800 thermal simulator, thermal simulations were performed through two-stage deformations in the austenite zone. Ferrite transformation rules were studied with thermal simulation tests under different deformation and cooling parameters based on the actual production of cumulative deformation. The influence of deformation parameters on the microstructure transformation was analyzed. Numerous fine-grain deformation-induced ferrites were obtained by regulating various parameters, including deformation temperature, strain rate, cooling rate, final cooling temperature and other parameters. Results of metallographic observation and microtensile testing revealed that the selection of appropriate parameters can refine the grains and improve the performance of the X70HD pipeline steel.

Heterogeneous Deformable Modeling of Bio-Tissues and Haptic Force Rendering for Bio-Object Modeling

NASA Astrophysics Data System (ADS)

Lin, Shiyong; Lee, Yuan-Shin; Narayan, Roger J.

This paper presents a novel technique for modeling soft biological tissues as well as the development of an innovative interface for bio-manufacturing and medical applications. Heterogeneous deformable models may be used to represent the actual internal structures of deformable biological objects, which possess multiple components and nonuniform material properties. Both heterogeneous deformable object modeling and accurate haptic rendering can greatly enhance the realism and fidelity of virtual reality environments. In this paper, a tri-ray node snapping algorithm is proposed to generate a volumetric heterogeneous deformable model from a set of object interface surfaces between different materials. A constrained local static integration method is presented for simulating deformation and accurate force feedback based on the material properties of a heterogeneous structure. Biological soft tissue modeling is used as an example to demonstrate the proposed techniques. By integrating the heterogeneous deformable model into a virtual environment, users can both observe different materials inside a deformable object as well as interact with it by touching the deformable object using a haptic device. The presented techniques can be used for surgical simulation, bio-product design, bio-manufacturing, and medical applications.

Deformed Palmprint Matching Based on Stable Regions.

PubMed

Wu, Xiangqian; Zhao, Qiushi

2015-12-01

Palmprint recognition (PR) is an effective technology for personal recognition. A main problem, which deteriorates the performance of PR, is the deformations of palmprint images. This problem becomes more severe on contactless occasions, in which images are acquired without any guiding mechanisms, and hence critically limits the applications of PR. To solve the deformation problems, in this paper, a model for non-linearly deformed palmprint matching is derived by approximating non-linear deformed palmprint images with piecewise-linear deformed stable regions. Based on this model, a novel approach for deformed palmprint matching, named key point-based block growing (KPBG), is proposed. In KPBG, an iterative M-estimator sample consensus algorithm based on scale invariant feature transform features is devised to compute piecewise-linear transformations to approximate the non-linear deformations of palmprints, and then, the stable regions complying with the linear transformations are decided using a block growing algorithm. Palmprint feature extraction and matching are performed over these stable regions to compute matching scores for decision. Experiments on several public palmprint databases show that the proposed models and the KPBG approach can effectively solve the deformation problem in palmprint verification and outperform the state-of-the-art methods.

Case studies of spinal deformities in ornamental koi, Cyprinus carpio L.

PubMed

Chin, H N; Loh, R; Hong, Y C; Gibson-Kueh, S

2017-01-01

This is a study of vertebral deformities in ornamental koi based on computed radiography and skeletons cleaned by dermestid beetles (Dermestes maculatus). All koi developed gradual onset of swimming abnormalities as adults. Extensive intervertebral osteophyte formation correlated with age of fish and was associated with hindquarter paresis in one koi. Vertebral compression and fusion were the most common spinal deformities occurring at multiple sites, similar to findings in other farmed fish. Site-specific spinal deformities were thought to develop due to differences in swimming behaviour and rates of vertebral growth. One koi had offspring with spinal deformities. Spinal deformities are significant problems in both European and Australian food fish hatcheries. The heritability of vertebral deformities in farmed fish is reportedly low unless there is concurrent poor husbandry or nutritional deficiencies. The specific aetiologies for vertebral deformities in koi in this study could not be ascertained. Current knowledge on spinal deformities in the better studied European food fish species suggests multifactorial aetiologies. Future research should include prospective longitudinal studies of larger numbers of koi from hatch and consideration of all potential risk factors such as husbandry, nutrition, temperature, photoperiod and genetics. © 2016 John Wiley & Sons Ltd.

Massless conformal fields, AdS (d+1)/CFT d higher spin algebras and their deformations

DOE PAGES

Fernando, Sudarshan; Gunaydin, Murat

2016-02-04

Here, we extend our earlier work on the minimal unitary representation of SO(d, 2)and its deformations for d=4, 5and 6to arbitrary dimensions d. We show that there is a one-to-one correspondence between the minrep of SO(d, 2)and its deformations and massless conformal fields in Minkowskian spacetimes in ddimensions. The minrep describes a massless conformal scalar field, and its deformations describe massless conformal fields of higher spin. The generators of Joseph ideal vanish identically as operators for the quasiconformal realization of the minrep, and its enveloping algebra yields directly the standard bosonic AdS (d+1)/CFT d higher spin algebra. For deformed minrepsmore » the generators of certain deformations of Joseph ideal vanish as operators and their enveloping algebras lead to deformations of the standard bosonic higher spin algebra. In odd dimensions there is a unique deformation of the higher spin algebra corresponding to the spinor singleton. In even dimensions one finds infinitely many deformations of the higher spin algebra labelled by the eigenvalues of Casimir operator of the little group SO(d–2)for massless representations.« less

The incidence and treatment of rocker bottom deformity as a complication of the conservative treatment of idiopathic congenital clubfoot.

PubMed

Koureas, G; Rampal, V; Mascard, E; Seringe, R; Wicart, P

2008-01-01

Rocker bottom deformity may occur during the conservative treatment of idiopathic congenital clubfoot. Between 1975 and 1996, we treated 715 patients (1120 clubfeet) conservatively. A total of 23 patients (36 feet; 3.2%) developed a rocker bottom deformity. It is these patients that we have studied. The pathoanatomy of the rocker bottom deformity is characterised by a plantar convexity appearing between three and six months of age with the hindfoot equinus position remaining constant. The convexity initially involves the medial column, radiologically identified by the talo-first metatarsal angle and secondly by the lateral column, revealed radiologically as the calcaneo-fifth metatarsal angle. The apex of the deformity is usually at the midtrasal with a dorsal calcaneocuboid subluxation. Ideal management of clubfoot deformity should avoid this complication, with adequate manipulation and splinting and early Achilles' percutaneous tenotomy if plantar convexity occurs. Adequate soft-tissue release provides satisfactory correction for rocker bottom deformity. However, this deformity requires more extensive and complex procedures than the standard surgical treatment of clubfoot. The need for lateral radiographs to ensure that the rocker bottom deformity is recognised early, is demonstrated.

Chondro-manubrial deformity and bifid rib, rare variations seen in pectus carinatum: a radiological finding.

PubMed

Allwyn Joshua, S; Shetty, Lathika; Pare, V S; Sebastian, Roopa

2013-07-01

Pectus carinatum or protrusion deformity of chest wall is less frequently occurring anterior chest wall deformity when compared to pectus excavatum. It may be classified as type 1 or chondro-gladiolar and type 2 or chondro-manubrial deformity. Other variations seen are symmetrical and asymmetrical pectus carinatum. Here we present two unique case reports, one with chondro-manubrial deformity (Currarino-Silverman syndrome) and other with asymmetrical pectus carinatum having bifid rib which are some of the rare variations seen in pectus carinatum found during Computerized tomographic examination. Currarino-Silverman syndrome is a type 2 pectus carinatum, a rare deformity with chondro-manubrial involvement and usually associated congenital heart diseases. Early fusion of sternal plates is one of the known theories in producing this deformity. On the other hand, asymmetrical pectus deformity are usually seen due to imbalance or abnormality in growth plates of costal cartilages leading to forked rib or bifid rib, which are accidently seen on radiological examination. To conclude, our reports would help in differential diagnosis from frequently occurring conditions affecting chest like chondro-gladiolar deformity, pectus excavatum, chest wall tumours, rib fractures and intra thoracic ribs.

Westward-directed Grenvillian thrusting on the western margin of Fennoscandia: evidence from syn-kinematic pegmatites.

NASA Astrophysics Data System (ADS)

Henderson, I.

2004-12-01

Magmatism is often described as being syn-kinematic where one or more increments of intrusion punctuate deformation with successive generations of injections being progressively deformed. Recent studies have also demonstrated that there is a strong link between sites of concentrated magmatism and crustal deformation zones. Pegmatite formation in the Mesoproterozoic of south Norway has always been considered as post-kinematic in nature relative to Sveconorwegian (Grenvillian) deformation (1.13Ga to ~0.85Ga) during accretion of the SW margin of Baltica. We present structural data demonstrating that the pegmatites are kinematically related to fold geometries associated with peak metamorphism and form an integral part of the deformation episode associated with terrane accretion. Undeformed pegmatites are emplaced in sub-horizontal fractures suggesting that the maximum compressive stress was sub-horizontal. The pegmatites display a systematic deformation pattern that is consistent with deformation in the limbs of the isoclinal folds in the country rock into which they intrude. The sense of shear of deformation kinematics on the pegmatites reverse across the isoclinal fold limbs suggesting that the pegmatites are syn-deformational and that they have been injected into fractures intrinsically linked to the fold development. Pegmatites are also deformed into asymmetric anticlinal folds above thrust structures and are cut by thrust structures. We also present data which demonstrates that the style of deformation changes with proximity to the major terrane-bounding thrust structure and that the pegmatites demonstrate classic imbricate style geometries on a regional scale related to regional transpression. This evidence suggests that the pegmatites are syn-deformational and were injected into thrust-related fractures and that the pegmatites are structurally related to Sveconorwegian fold geometries associated with peak metamorphism at approximately 1.14Ga. Deformation was progressive and incremental with longer periods of ductile deformation at low strain rate punctuated by shorter periods of fracturing and pegmatite injection at high strain rate. The pegmatites also, therefore, delineate the orogenic event responsible for overthrusting of the Bamble Terrane with the underlying Telemark Terrane during crustal accretion on the western margin of Fennoscandia. We also present preliminary Re-Os data from some of these pegmatites to date the exact timing of thrusting. This work therefore implies an intimate spatial and temporal relationship between deformation and magmatism during crustal accretion on the western margin of Fennoscandia.

14 CFR 23.305 - Strength and deformation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength and deformation. 23.305 Section 23.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT..., permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation...

14 CFR 23.305 - Strength and deformation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength and deformation. 23.305 Section 23.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT..., permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation...

14 CFR 27.305 - Strength and deformation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength and deformation. 27.305 Section 27.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The...

14 CFR 27.305 - Strength and deformation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength and deformation. 27.305 Section 27.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The...

Dealing with spatial heterogeneity

NASA Astrophysics Data System (ADS)

Marsily, Gh.; Delay, F.; Gonçalvès, J.; Renard, Ph.; Teles, V.; Violette, S.

2005-03-01

Heterogeneity can be dealt with by defining homogeneous equivalent properties, known as averaging, or by trying to describe the spatial variability of the rock properties from geologic observations and local measurements. The techniques available for these descriptions are mostly continuous Geostatistical models, or discontinuous facies models such as the Boolean, Indicator or Gaussian-Threshold models and the Markov chain model. These facies models are better suited to treating issues of rock strata connectivity, e.g. buried high permeability channels or low permeability barriers, which greatly affect flow and, above all, transport in aquifers. Genetic models provide new ways to incorporate more geology into the facies description, an approach that has been well developed in the oil industry, but not enough in hydrogeology. The conclusion is that future work should be focused on improving the facies models, comparing them, and designing new in situ testing procedures (including geophysics) that would help identify the facies geometry and properties. A world-wide catalog of aquifer facies geometry and properties, which could combine site genesis and description with methods used to assess the system, would be of great value for practical applications. On peut aborder le problème de l'hétérogénéité en s'efforçant de définir une perméabilité équivalente homogène, par prise de moyenne, ou au contraire en décrivant la variation dans l'espace des propriétés des roches à partir des observations géologiques et des mesures locales. Les techniques disponibles pour une telle description sont soit continues, comme l'approche Géostatistique, soit discontinues, comme les modèles de faciès, Booléens, ou bien par Indicatrices ou Gaussiennes Seuillées, ou enfin Markoviens. Ces modèles de faciès sont mieux capables de prendre en compte la connectivité des strates géologiques, telles que les chenaux enfouis à forte perméabilité, ou au contraire les faciès fins de barrières de perméabilité, qui ont une influence importante sur les écoulement, et, plus encore, sur le transport. Les modè les génétiques récemment apparus ont la capacité de mieux incorporer dans les modèles de faciès les observations géologiques, chose courante dans l'industrie pétrolière, mais insuffisamment développée en hydrogéologie. On conclut que les travaux de recherche ultérieurs devraient s'attacher à développer les modèles de faciès, à les comparer entre eux, et à mettre au point de nouvelles méthodes d'essais in situ, comprenant les méthodes géophysiques, capables de reconnaître la géométrie et les propriétés des faciès. La constitution d'un catalogue mondial de la géométrie et des propriétés des faciès aquifères, ainsi que des méthodes de reconnaissance utilisées pour arriver à la détermination de ces systèmes, serait d'une grande importance pratique pour les applications. La heterogeneidad se puede manejar por medio de la definición de características homogéneas equivalentes, conocidas como promediar o tratando de describir la variabilidad espacial de las características de las rocas a partir de observaciones geológicas y medidas locales. Las técnicas disponibles para estas descripciones son generalmente modelos geoestadísticos continuos o modelos de facies discontinuos como los modelos Boolean, de Indicador o de umbral de Gaussian y el modelo de cadena de Markow. Estos modelos de facies son mas adecuados para tratar la conectvidad de estratos geológicos (por ejemplo canales de alta permeabilidad enterrados o barreras de baja permeabilidad que tienen efectos importantes sobre el flujo y especialmente sobre el transporte en los acuíferos. Los modelos genéticos ofrecen nuevas formas de incorporar más geología en las descripciones de facies, un enfoque que está bien desarollado en la industria petrolera, pero insuficientemente en la hidrogeología. Se concluye que los trabajos futuros deberían estar más enfocados en mejorar los modelos de facies, en establecer comparaciones y en diseñar nuevos procedimientos para pruebas in-situ (incuyendo la geofísica) que pueden ayudar a identificar la geometría de las facies y sus propiedades. Un catálogo global de la geometría de las facies de los acuíferos y sus características, que podría combinar la génesis de los sitios y descripciones de los métodos utilizados para evaluar el sistema, sería de gran valor para las aplicaciones prácticas.

Effect of reconstructive vascular surgery on red cell deformability--preliminary results.

PubMed Central

Irwin, S T; Rocks, M J; McGuigan, J A; Patterson, C C; Morris, T C; O'Reilly, M J

1983-01-01

Using a simple filtration method, red cell deformability was measured in healthy control subjects and in patients with peripheral vascular disease. Impaired red cell deformability was demonstrated in patients with rest pain or gangrene and in patients with intermittent claudication. An improvement in red cell deformability was demonstrated after successful reconstructive vascular surgery in both patient groups. An improvement in red cell deformability was demonstrated in patients undergoing major limb amputation. PMID:6619311

How deformed are the TSD bands in odd Lu isotopes?

NASA Astrophysics Data System (ADS)

Ragnarsson, I.

2017-12-01

The experimental fingerprints for large deformation in the triaxial strongly deformed (TSD) bands of 163,165,167Lu are discussed. It is argued that these fingerprints are not very convincing. On the contrary, especially the fact that there exist strong interactions between the TSD bands and normal-deformed (ND) bands indicates that the deformation of the TSD bands cannot be very different from that of the ND bands. The need for detailed new experimental data is underlined.

Comparative study on different types of segmented micro deformable mirrors

NASA Astrophysics Data System (ADS)

Qiao, Dayong; Yuan, Weizheng; Li, Kaicheng; Li, Xiaoying; Rao, Fubo

2006-02-01

In an adaptive-optical (AO) system, the wavefront of optical beam can be corrected with deformable mirror (DM). Based on MicroElectroMechanical System (MEMS) technology, segmented micro deformable mirrors can be built with denser actuator spacing than continuous face-sheet designs and have been widely researched. But the influence of the segment structure has not been thoroughly discussed until now. In this paper, the design, performance and fabrication of several micromachined, segmented deformable mirror for AO were investigated. The wavefront distorted by atmospheric turbulence was simulated in the frame of Kolmogorov turbulence model. Position function was used to describe the surfaces of the micro deformable mirrors in working state. The performances of deformable mirrors featuring square, brick, hexagonal and ring segment structures were evaluated in criteria of phase fitting error, the Strehl ratio after wavefront correction and the design considerations. Then the micro fabrication process and mask layout were designed and the fabrication of micro deformable mirrors was implemented. The results show that the micro deformable mirror with ring segments performs the best, but it is very difficult in terms of layout design. The micro deformable mirrors with square and brick segments are easy to design, but their performances are not good. The micro deformable mirror with hexagonal segments has not only good performance in terms of phase fitting error, the Strehl ratio and actuation voltage, but also no overwhelming difficulty in layout design.

Impact of large field angles on the requirements for deformable mirror in imaging satellites

NASA Astrophysics Data System (ADS)

Kim, Jae Jun; Mueller, Mark; Martinez, Ty; Agrawal, Brij

2018-04-01

For certain imaging satellite missions, a large aperture with wide field-of-view is needed. In order to achieve diffraction limited performance, the mirror surface Root Mean Square (RMS) error has to be less than 0.05 waves. In the case of visible light, it has to be less than 30 nm. This requirement is difficult to meet as the large aperture will need to be segmented in order to fit inside a launch vehicle shroud. To reduce this requirement and to compensate for the residual wavefront error, Micro-Electro-Mechanical System (MEMS) deformable mirrors can be considered in the aft optics of the optical system. MEMS deformable mirrors are affordable and consume low power, but are small in size. Due to the major reduction in pupil size for the deformable mirror, the effective field angle is magnified by the diameter ratio of the primary and deformable mirror. For wide field of view imaging, the required deformable mirror correction is field angle dependant, impacting the required parameters of a deformable mirror such as size, number of actuators, and actuator stroke. In this paper, a representative telescope and deformable mirror system model is developed and the deformable mirror correction is simulated to study the impact of the large field angles in correcting a wavefront error using a deformable mirror in the aft optics.

Predicting Welding Distortion in a Panel Structure with Longitudinal Stiffeners Using Inherent Deformations Obtained by Inverse Analysis Method

PubMed Central

Liang, Wei; Murakawa, Hidekazu

2014-01-01

Welding-induced deformation not only negatively affects dimension accuracy but also degrades the performance of product. If welding deformation can be accurately predicted beforehand, the predictions will be helpful for finding effective methods to improve manufacturing accuracy. Till now, there are two kinds of finite element method (FEM) which can be used to simulate welding deformation. One is the thermal elastic plastic FEM and the other is elastic FEM based on inherent strain theory. The former only can be used to calculate welding deformation for small or medium scale welded structures due to the limitation of computing speed. On the other hand, the latter is an effective method to estimate the total welding distortion for large and complex welded structures even though it neglects the detailed welding process. When the elastic FEM is used to calculate the welding-induced deformation for a large structure, the inherent deformations in each typical joint should be obtained beforehand. In this paper, a new method based on inverse analysis was proposed to obtain the inherent deformations for weld joints. Through introducing the inherent deformations obtained by the proposed method into the elastic FEM based on inherent strain theory, we predicted the welding deformation of a panel structure with two longitudinal stiffeners. In addition, experiments were carried out to verify the simulation results. PMID:25276856

Predicting welding distortion in a panel structure with longitudinal stiffeners using inherent deformations obtained by inverse analysis method.

PubMed

Liang, Wei; Murakawa, Hidekazu

2014-01-01

Welding-induced deformation not only negatively affects dimension accuracy but also degrades the performance of product. If welding deformation can be accurately predicted beforehand, the predictions will be helpful for finding effective methods to improve manufacturing accuracy. Till now, there are two kinds of finite element method (FEM) which can be used to simulate welding deformation. One is the thermal elastic plastic FEM and the other is elastic FEM based on inherent strain theory. The former only can be used to calculate welding deformation for small or medium scale welded structures due to the limitation of computing speed. On the other hand, the latter is an effective method to estimate the total welding distortion for large and complex welded structures even though it neglects the detailed welding process. When the elastic FEM is used to calculate the welding-induced deformation for a large structure, the inherent deformations in each typical joint should be obtained beforehand. In this paper, a new method based on inverse analysis was proposed to obtain the inherent deformations for weld joints. Through introducing the inherent deformations obtained by the proposed method into the elastic FEM based on inherent strain theory, we predicted the welding deformation of a panel structure with two longitudinal stiffeners. In addition, experiments were carried out to verify the simulation results.

The role of red blood cell deformability and Na,K-ATPase function in selected risk factors of cardiovascular diseases in humans: focus on hypertension, diabetes mellitus and hypercholesterolemia.

PubMed

Radosinska, J; Vrbjar, N

2016-09-19

Deformability of red blood cells (RBC) is the ability of RBC to change their shape in order to pass through narrow capillaries in circulation. Deterioration in deformability of RBC contributes to alterations in microcirculatory blood flow and delivery of oxygen to tissues. Several factors are responsible for maintenance of RBC deformability. One of them is the Na,K-ATPase known as crucial enzyme in maintenance of intracellular ionic homeostasis affecting thus regulation of cellular volume and consequently RBC deformability. Decreased deformability of RBC has been found to be the marker of adverse outcomes in cardiovascular diseases (CVD) and the presence of cardiovascular risk factors influences rheological properties of the blood. This review summarizes knowledge concerning the RBC deformability in connection with selected risk factors of CVD, including hypertension, hyperlipidemia, and diabetes mellitus, based exclusively on papers from human studies. We attempted to provide an update on important issues regarding the role of Na,K-ATPase in RBC deformability. In patients suffering from hypertension as well as diabetes mellitus the Na,K-ATPase appears to be responsible for the changes leading to alterations in RBC deformability. The triggering factor for changes of RBC deformability during hypercholesterolemia seems to be the increased content of cholesterol in erythrocyte membranes.

The effect of deformation temperature on the microstructure evolution of Inconel 625 superalloy

NASA Astrophysics Data System (ADS)

Guo, Qingmiao; Li, Defu; Guo, Shengli; Peng, Haijian; Hu, Jie

2011-07-01

Hot compression tests of Inconel 625 superalloy were conducted using a Gleeble-1500 simulator between 900 °C and 1200 °C with different true strains and a strain rate of 0.1 s -1. Scanning electron microscope (SEM) and electron backscatter diffraction technique (EBSD) were employed to investigate the effect of deformation temperature on the microstructure evolution and nucleation mechanisms of dynamic recrystallization (DRX). It is found that the relationship between the DRX grain size and the peak stress can be expressed by a power law function. Significant influence of deformation temperatures on the nucleation mechanisms of DRX are observed at different deformation stages. At lower deformation temperatures, continuous dynamic recrystallization (CDRX) characterized by progressive subgrain rotation is considered as the main mechanism of DRX at the early deformation stage. However, discontinuous dynamic recrystallization (DDRX) with bulging of the original grain boundaries becomes the operating mechanism of DRX at the later deformation stage. At higher deformation temperatures, DDRX is the primary mechanism of DRX, while CDRX can only be considered as an assistant mechanism at the early deformation stage. Nucleation of DRX can also be activated by the twinning formation. With increasing the deformation temperature, the effect of DDRX accompanied with twinning formation grows stronger, while the effect of CDRX grows weaker. Meanwhile, the position of subgrain formation shifts gradually from the interior of original grains to the vicinity of the original boundaries.

Testing deformation hypotheses by constraints on a time series of geodetic observations

NASA Astrophysics Data System (ADS)

Velsink, Hiddo

2018-01-01

In geodetic deformation analysis observations are used to identify form and size changes of a geodetic network, representing objects on the earth's surface. The network points are monitored, often continuously, because of suspected deformations. A deformation may affect many points during many epochs. The problem is that the best description of the deformation is, in general, unknown. To find it, different hypothesised deformation models have to be tested systematically for agreement with the observations. The tests have to be capable of stating with a certain probability the size of detectable deformations, and to be datum invariant. A statistical criterion is needed to find the best deformation model. Existing methods do not fulfil these requirements. Here we propose a method that formulates the different hypotheses as sets of constraints on the parameters of a least-squares adjustment model. The constraints can relate to subsets of epochs and to subsets of points, thus combining time series analysis and congruence model analysis. The constraints are formulated as nonstochastic observations in an adjustment model of observation equations. This gives an easy way to test the constraints and to get a quality description. The proposed method aims at providing a good discriminating method to find the best description of a deformation. The method is expected to improve the quality of geodetic deformation analysis. We demonstrate the method with an elaborate example.

Sensitivity study of voxel-based PET image comparison to image registration algorithms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yip, Stephen, E-mail: syip@lroc.harvard.edu; Chen, Aileen B.; Berbeco, Ross

2014-11-01

Purpose: Accurate deformable registration is essential for voxel-based comparison of sequential positron emission tomography (PET) images for proper adaptation of treatment plan and treatment response assessment. The comparison may be sensitive to the method of deformable registration as the optimal algorithm is unknown. This study investigated the impact of registration algorithm choice on therapy response evaluation. Methods: Sixteen patients with 20 lung tumors underwent a pre- and post-treatment computed tomography (CT) and 4D FDG-PET scans before and after chemoradiotherapy. All CT images were coregistered using a rigid and ten deformable registration algorithms. The resulting transformations were then applied to themore » respective PET images. Moreover, the tumor region defined by a physician on the registered PET images was classified into progressor, stable-disease, and responder subvolumes. Particularly, voxels with standardized uptake value (SUV) decreases >30% were classified as responder, while voxels with SUV increases >30% were progressor. All other voxels were considered stable-disease. The agreement of the subvolumes resulting from difference registration algorithms was assessed by Dice similarity index (DSI). Coefficient of variation (CV) was computed to assess variability of DSI between individual tumors. Root mean square difference (RMS{sub rigid}) of the rigidly registered CT images was used to measure the degree of tumor deformation. RMS{sub rigid} and DSI were correlated by Spearman correlation coefficient (R) to investigate the effect of tumor deformation on DSI. Results: Median DSI{sub rigid} was found to be 72%, 66%, and 80%, for progressor, stable-disease, and responder, respectively. Median DSI{sub deformable} was 63%–84%, 65%–81%, and 82%–89%. Variability of DSI was substantial and similar for both rigid and deformable algorithms with CV > 10% for all subvolumes. Tumor deformation had moderate to significant impact on DSI for progressor subvolume with R{sub rigid} = − 0.60 (p = 0.01) and R{sub deformable} = − 0.46 (p = 0.01–0.20) averaging over all deformable algorithms. For stable-disease subvolumes, the correlations were significant (p < 0.001) for all registration algorithms with R{sub rigid} = − 0.71 and R{sub deformable} = − 0.72. Progressor and stable-disease subvolumes resulting from rigid registration were in excellent agreement (DSI > 70%) for RMS{sub rigid} < 150 HU. However, tumor deformation was observed to have negligible effect on DSI for responder subvolumes with insignificant |R| < 0.26, p > 0.27. Conclusions: This study demonstrated that deformable algorithms cannot be arbitrarily chosen; different deformable algorithms can result in large differences of voxel-based PET image comparison. For low tumor deformation (RMS{sub rigid} < 150 HU), rigid and deformable algorithms yield similar results, suggesting deformable registration is not required for these cases.« less