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Sample records for educativas elementos para

  1. Inversor Resonante de Tres Elementos L-LC con Caracteristica Cortocircuitable para Aplicaciones de Calentamiento por Induccion

    NASA Astrophysics Data System (ADS)

    Espi Huerta, Jose Miguel

    Los generadores de calentamiento por induccion son puentes inversores con carga resonante, cuya mision es basicamente crear una corriente sinusoidal de gran amplitud sobre la "bobina de caldeo", que forma parte del tanque resonante. En el interior de esta bobina se introduce la pieza que se desea calentar. EI campo magnetico creado induce corrientes superficiales (corrientes de Foucault) sobre la pieza, que producen su calentamiento. Los tanques resonantes (tambien llamados osciladores) utilizados en la actualidad son el resonante serie y el resonante paralelo. Aunque ya desde hace algun tiempo se vienen construyendo generadores de alta potencia basados en estos dos osciladores, el exito nunca ha. sido completo en ninguno de los dos casos. Tal y como se explica en la introduccion de esta memoria, los puentes inversores utilizados deben operar sobre una carga inductiva (corriente retrasada) para evitar el fenomeno de la recuperacion inversa de sus diodos y la consiguiente ruptura de los transistores. De la restriccion topologica anterior se deduce que el generador paralelo debe conmutar a frecuencias inferiores a la resonancia, y el serie a frecuencias superiores. A esta restriccion topologica hay que unir otra que es exclusiva del calentamiento por induccion: La corriente por la bobina de caldeo debe ser sinusoidal. De no ser asi, resultaria imposible disponer toda la potencia de calentamiento sobre la pieza en el espesor requerido por la aplicacion. Como consecuencia, los inversores no pueden operar por debajo de la frecuencia de resonancia del oscilador, pues en ese caso se amplifican los armonicos de orden superior de la tension/corriente de entrada situados sobre la resonancia, con la consiguiente distorsion de la corriente de salida. La conjuncion de las dos restricciones anteriores obligan al inversor paralelo a funcionar a la frecuencia de resonancia del oscilador. Esto imposibilita un control por variacion de frecuencia, regulandose la potencia desde la

  2. Revista Investigacion Educativa, 1992-1995.

    ERIC Educational Resources Information Center

    Revista Investigacion Educativa, 1995

    1995-01-01

    This document consists of the eight issues of the series "Revista Investigacion Educativa" published during the 4-year period 1992-1995. This review of educational investigation seeks to promote the exchange of information about empirical research in education. It is published semiannually, and includes reports of both quantitative and qualitative…

  3. Reforma Educativa: Proyecto de Reforma Educativa para Francia (Educational Reform: French Educational Reform Proposals).

    ERIC Educational Resources Information Center

    Langevin, Paul

    This document is a Spanish translation of French educational reform proposals and general educational philosophy. Initial remarks in the document concern educational objectives and general aims of the particular educational levels. Different, possible, educational progressions are considered, and the university system is discussed. Teacher…

  4. Determinação de elementos próprios dos asteróides troianos: comparação entre as teorias semi-analítica e sintética

    NASA Astrophysics Data System (ADS)

    Roig, F.; Beaugé, C.

    2003-08-01

    Além do cálculo semi-analítico de elementos próprios dos asteróides Troianos (Beaugé & Roig 2001, Icarus 153, 391), recentemente foi apresentado um novo conjunto destes elementos próprios determinado através de uma teoria sintética (Knenezevic & Milani 2003, comunicação pessoal). As bases de dados contendo estas determinações estão disponiveis na pagina web do Asteroid Dynamical Site (http://hamilton.dm.unipi.it/cgi-bin/astdys/astibo). Nesta comunicação apresentamos os primeiros resultados de um estudo comparativo entre ambos conjuntos de elementos próprios, analisando suas vantagens e desvantagens, assim como os limites de precisão de cada conjunto. Mostramos que os elementos próprios sintéticos são mais precisos que os smi-analíticos para grandes amplitudes de libração do ângulo s = l-lJup, embora acontece o contrario para os corpos cuja amplitude de libração é muito pequena. Finalmente discutimos a influencia destes erros na determinação de familias de asteroides e da estrutura resonante em torno dos pontos Lagrangeanos L4 e L5.

  5. Education Through Aerospace Components. (Spanish Title: Educación Através de Elementos Aeroespaciales.) Educação Através de Elementos Aeroespaciais

    NASA Astrophysics Data System (ADS)

    Barbosa Loureda, Oswaldo; Sobral de Araújo, Jéssyca B.

    2008-12-01

    Education is a field that needs development. For such purposes, there are various methods and tools that suggest ideas in favor of the improvement of the Brazilian people in the pedagogical, psychological and cultural aspects. Teaching is an act that demands a lot of care and responsibility; the behavior and performance of an individual in the society is the result of way that people was educated. However, the area of hard sciences demands a special attention, because the acquired knowledge is essential for the personal development of the individual and the technological future of the country. As an alternative or complementary tool for education it is suggested the use of aerospace element, since they show a vast amount of subjects qualitatively dealing with abilities of great importance for the future professional life of the students. A new Race happens, however this time the goal is not the Moon, but knowledge. El área educacional es un campo que necesita desarrollo. Para esto se dispone de diversos métodos y medios que pueden implantar ideas en pro del avance del pueblo brasilero en los aspectos pedagógicos, psicológicos y culturales. Alfabetizar es un acto que exige mucho cuidado y responsabilidad; el comportamento y desempeño de un individuo en la sociedad es el resultado de la manera en que fue educado. En particular, el área de ciencias exactas exige especial atención, pues los conocimientos adquiridos son imprescindibles para el desarrollo personal del individuo y también para el futuro tecnológico del País. Como medio alternativo o complementar de enseñanza se sugiere el uso de elementos aeroespaciales, debido a que compreende una vasta cantidad de disciplinas cualitativamente involucradas en la adquisición de habilidades de gran importancia para su vida profesional futura. Una nueva Carrera está em marcha, sin embargo esta vez la meta no es la Luna, sino el conocimiento. A área educacional é um campo que necessita de desenvolvimento. Para

  6. 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

  7. Educadores Polivalentes: Alternativa Educativa para Comunidades Rurales (Effective Educators: Alternative Education for Rural Communities).

    ERIC Educational Resources Information Center

    Godoy, Rodrigo Vera

    The document provides educators with data and information regarding the utilization of alternative educational processes in Latin American rural communities. Many communities exist at social and economic poverty levels and are isolated from urban centers. Documents compiled for use at alternative education conferences, held in Paipa, Colombia in…

  8. Documentos de consulta para iniciar la reforma educativa (Preparatory documents on educational reform).

    ERIC Educational Resources Information Center

    Consejo Nacional Tecnico de la Educacion (Mexico).

    This document is an English-language abstract (approximately 1,500 words) of two booklets on Mexican educational reform. The first booklet cites the parts of the Mexican Constitution dealing with education, the legal foundation of Mexican education, stipulating that it shall be universal, democratic, national, compulsory, free and immune from…

  9. [Literatura y Laminas Educativas para Ninos.] [Selected Children's Literature and Learning Charts.

    ERIC Educational Resources Information Center

    1968

    Folk stories have been published in Spanish to provide the Spanish-speaking child with reading materials in his native language. Series of materials are available for instruction in numbers and letters and beginning and intermediate vocabulary development. Series are Abecedarios (13 vols.), Mis Animalitos (6 vols.), Coleccion Oficios y Animales (6…

  10. Communicating the New Chemistry in 18th-Century Portugal: Seabra's "Elementos de Chimica"

    ERIC Educational Resources Information Center

    Carneiro, Ana; Diogo, Maria Paula; Simoes, Ana

    2006-01-01

    In this paper, we analyse the aims, contents and impact of Seabra's two-volume textbook--"Elementos de Chimica" ("Elements of Chemistry")--published in 1788 and 1790. Seabra's "Elements of Chemistry" does not conform to the characteristics usually ascribed to textbooks by traditional historiography, and in particular to textbooks published in the…

  11. La dinámica demográfica y la desigualdad educativa en Méxicoa

    PubMed Central

    Giorguli Saucedo, Silvia E.; Vargas Valle, Eunice D.; Ulloa, Viviana Salinas; Hubert, Celia; Potter, Joseph E.

    2015-01-01

    En este trabajo se presenta una investigación sobre el vínculo entre los procesos educativos y la dinámica demográfica en México. La tradición del pensamiento sobre población y desarrollo ha partido de la hipótesis de que el ritmo de crecimiento poblacional, el tamaño de las familias y la migración influyen sobre la acumulación de capital humano entre la población en edades escolares. Se explora aquí la relación del desempeño educativo de los jóvenes entre 14 y 23 años y la razón de dependencia juvenil, la fecundidad adolescente y la migración interna e internacional; para ello se utilizan datos agregados a escala municipal del año 2000. El análisis incluye indicadores de la oferta educativa municipal basados en estadísticas administrativas de la SEP. PMID:26146427

  12. Praxis educativa ecopacifista de enriquecimiento curricular: Conceptuacion, diseno y divulgacion

    NASA Astrophysics Data System (ADS)

    Osorio, Carlos Agustin Muniz

    A general consensus exists that the present worldwide state of the natural environment is in crisis. Tied to this crisis, the social dimension presents a discouraging picture in aspects like violence and poverty. The predominant neoliberal economic system---ecocidal and genocidal---just as the production system that sustains it, affects this crisis. Puerto Rico, in its political and economic relationship with the United States of America, is not exempt of this situation. Education arises as an alternative to transform this reality. Science education has the potential to address these socio-environmental problems in a creative way. From a scientific educational framework, we conceptualized, designed and disseminated diverse approaches and tools that integrate socio-ecological and environmental aspects, as well as issues related to violence, conflict and peace. The central research questions were: At present, what are some of the main characteristics of the social-ecological and environmental global and local (glocal) issues and what relation do they have with formal education?; What is the ethical responsibility of science education when, facing social-ecological and environmental situations and issues concerning peace?; What educational foundations justify the "Praxis Educativa Ecopacifista de Enriquecimiento Curricular" as an alternative to the situations and issues considered?; What didactic tools do we propose?; What curricular design and revision processes do we propose? What dissemination processes do we propose? The nature of our methodology is qualitative and is centered around curricular design. It includes a research-theoretical dimension, a practical-research dimension, and systematizing of learning elements. We emphasize the conceptualization of the theoretical-philosophical and methodological dimensions of the ecopacifist approach and its fundamental principles. We highlight the praxis, integrating creativity, intelligence and talent development

  13. Fundamentos, Orientaciones, Areas Basicas y Procedimientos para la Investigacion Educativa (Bases, Guidelines, Basic Areas, and Procedures for Educational Research).

    ERIC Educational Resources Information Center

    Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.

    This document establishes the bases, general guidelines, basic areas, and procedures for educational research conducted in Colombia. The philosophy underlying research objectives is explained. There is special interest in social research concerning the condition of man and of the social groups that will be the targets of education, and in research…

  14. Tecnologia educativa: Lengua nacional 1. Guiones didacticos para el profesor (Educational Technology: National Language 1. Teacher's Guide).

    ERIC Educational Resources Information Center

    Peniche Leger, Maria Elena

    This is the first in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  15. Tecnologia educativa: Lengua nacional 4. Guiones didacticos para el profesor (Educational Technology: National Language 4. Teacher's Guide).

    ERIC Educational Resources Information Center

    Peniche Leger, Maria Elena

    This is the fourth in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  16. Tecnologia educativa: Lengua nacional 2. Guiones didacticos para el profesor (Educational Technology: National Language 2. Teacher's Guide).

    ERIC Educational Resources Information Center

    Peniche Leger, Maria Elena

    This is the second in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  17. Tecnologia educativa: Lengua nacional 5. Guiones didacticos para el profesor (Educational Technology: National Language 5. Teacher's Guide).

    ERIC Educational Resources Information Center

    Peniche Leger, Maria Elena

    This is the fifth in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  18. Tecnologia educativa: Lengua nacional 6. Guiones didacticos para el profesor (Educational Technology: National Language 6. Teacher's Guide).

    ERIC Educational Resources Information Center

    Peniche Leger, Maria Elena

    This is the sixth in a series of six teacher's guides designed to accompany the Senda textbooks (FL 004 047 through 004 052). It contains instructions for presenting the lessons and for handling the individual needs of the pupils. (Author/SK)

  19. Servicio de Informacion para la Orientacion Educativa. Guia para su Interpretacion y Uso. (Information Service for Educational Counseling. Guide for Its Interpretation and Use.)

    ERIC Educational Resources Information Center

    College Entrance Examination Board, Hato Rey, PR. Puerto Rico Office.

    In 1974, the College Board in Puerto Rico initiated a program on educational counseling for high school-bound students. The program was designed to help students define their educational goals and career interests before entering the ninth grade where they would be required to make specific curriculum choices. The program calls for the…

  20. Alianza para el Aprendizaje: Una guia de actividades educativas para familias (Alliance for Learning: A Guide of Educational Activities for Families).

    ERIC Educational Resources Information Center

    Carr, Phil

    This Spanish-language publication condenses the information in the Alliance for Learning series. The publication is intended principally for families with preschool or primary grade children, although the material can be used with older children. The sections of the publication address various themes and present activities that parents can do with…

  1. Vínculos observacionais para o processo-S em estrelas gigantes de Bário

    NASA Astrophysics Data System (ADS)

    Smiljanic, R. H. S.; Porto de Mello, G. F.; da Silva, L.

    2003-08-01

    Estrelas de bário são gigantes vermelhas de tipo GK que apresentam excessos atmosféricos dos elementos do processo-s. Tais excessos são esperados em estrelas na fase de pulsos térmicos do AGB (TP-AGB). As estrelas de bário são, no entanto, menos massivas e menos luminosas que as estrelas do AGB, assim, não poderiam ter se auto-enriquecido. Seu enriquecimento teria origem em uma estrela companheira, inicialmente mais massiva, que evolui pelo TP-AGB, se auto-enriquece com os elementos do processo-s e transfere material contaminado para a atmosfera da atual estrela de bário. A companheira evolui então para anã branca deixando de ser observada diretamente. As estrelas de bário são, portanto, úteis como testes observacionais para teorias de nucleossíntese pelo processo-s, convecção e perda de massa. Análises detalhadas de abundância com dados de alta qualidade para estes objetos são ainda escassas na literatura. Neste trabalho construímos modelos de atmosferas e, procedendo a uma análise diferencial, determinamos parâmetros atmosféricos e evolutivos de uma amostra de dez gigantes de bário e quatro normais. Determinamos seus padrões de abundância para Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu e Gd, concluindo que algumas estrelas classificadas na literatura como gigantes de bário são na verdade gigantes normais. Comparamos dois padrões médios de abundância, para estrelas com grandes excessos e estrelas com excessos moderados, com modelos teóricos de enriquecimento pelo processo-s. Os dois grupos de estrelas são ajustados pelos mesmos parâmetros de exposição de nêutrons. Tal resultado sugere que a ocorrência do fenômeno de bário com diferentes intensidades não se deve a diferentes exposições de nêutrons. Discutimos ainda efeitos nucleossintéticos, ligados ao processo-s, sugeridos na literatura para os elementos Cu, Mn, V e Sc.

  2. Using Pictures Series Technique to Enhance Narrative Writing among Ninth Grade Students at Institución Educativa Simón Araujo

    ERIC Educational Resources Information Center

    Gutiérrez, Katia Gregoria Contreras; Puello, Miriam Niño; Galvis, Luis Alberto Pérez

    2015-01-01

    This study reports an action research on the use of pictures series technique to develop EFL narrative writing among a group of ninth graders at Institución Educativa Simon Araujo. It involves Experimental and Control groups. During the implementation of the strategy the Experiment group was taught writing with picture series technique and the…

  3. Proveer igualdad de oportunidades educativas para los estudiantes con conocimientos limitados del idioma ingles (Providing Equality of Educational Opportunity for Students with Limited Knowledge of the English Language).

    ERIC Educational Resources Information Center

    Office for Civil Rights (ED), Washington, DC.

    This brochure, entirely in Spanish, provides information on federal policy concerning equal educational opportunity for limited-English-proficient (LEP) individuals. It first summarizes the provisions of Title VI of the 1964 Civil Rights Act, and the subsequent major Civil Rights Office directives concerning that legislation. It then outlines…

  4. Tiempo para un cambio

    NASA Astrophysics Data System (ADS)

    Woltjer, L.

    1987-06-01

    En la reunion celebrada en diciembre dei ano pasado informe al Consejo de mi deseo de terminar mi contrato como Director General de la ESO una vez que fuera aprobado el proyecto dei VLT, que se espera sucedera hacia fines de este aAo. Cuando fue renovada mi designacion hace tres aAos, el Consejo conocia mi intencion de no completar los cinco aAos dei contrato debido a mi deseo de disponer de mas tiempo para otras actividades. Ahora, una vez terminada la fase preparatoria para el VLT, Y habiendose presentado el proyecto formalmente al Consejo el dia 31 de marzo, y esperando su muy probable aprobacion antes dei termino de este ano, me parece que el 10 de enero de 1988 presenta una excelente fecha para que se produzca un cambio en la administracion de la ESO.

  5. Validation Evidence for the Elementary School Version of the MUSIC® Model of Academic Motivation Inventory (Pruebas de validación para el Modelo MUSIC® de Inventario de Motivación Educativa para Escuela Primaria)

    ERIC Educational Resources Information Center

    Jones, Brett D.; Sigmon, Miranda L.

    2016-01-01

    Introduction: The purpose of our study was to assess whether the Elementary School version of the MUSIC® Model of Academic Motivation Inventory was valid for use with elementary students in classrooms with regular classroom teachers and student teachers enrolled in a university teacher preparation program. Method: The participants included 535…

  6. Microexperiencia Educativa (Microeducational Experimentation).

    ERIC Educational Resources Information Center

    Burton Meis, Roberto

    1970-01-01

    Experimentation for educational reform in Argentina is limited to specifically designated schools which are to be in a permanent state of experimentation. This article presents the official statements designating the experimental schools and includes remarks covering administration, evaluation, and supervision. (VM)

  7. Obtención de perfiles teóricos de elementos metálicos con velocidades macroscópicas

    NASA Astrophysics Data System (ADS)

    Cirigliano, D.; Costa, A.; Rovira, M.

    El propósito de este trabajo es poder establecer -a partir de la modelización de perfiles de distintas especies- patrones de comparación observacional que permitan caracterizar los fenómenos físicos que están presentes en las estructuras que se observan. Para ello se resuelven las ecuaciones de equilibrio de ionización para un determinado átomo y una atmósfera de parámetros determinados. A partir de ello se definen las poblaciones para los distintos grados de ionización. Considerando distintas configuraciones e intensidades de flujos de masa se deducen la función fuente, el espesor óptico y se calculan los perfiles de las distintas líneas. Se obtuvieron perfiles teóricos de líneas del CII, CIV y del OIV para flujos entrante, saliente y pasante. La forma del perfil, las intensidades relativas entre los distintos flujos y el corrimiento Doppler da cuenta de una caracterización teórica a partir de la cual se comparará con observaciones.

  8. Separating para and ortho water.

    PubMed

    Horke, Daniel A; Chang, Yuan-Pin; Długołęcki, Karol; Küpper, Jochen

    2014-10-27

    Water exists as two nuclear-spin isomers, para and ortho, determined by the overall spin of its two hydrogen nuclei. For isolated water molecules, the conversion between these isomers is forbidden and they act as different molecular species. Yet, these species are not readily separated, and no pure para sample has been produced. Accordingly, little is known about their specific physical and chemical properties, conversion mechanisms, or interactions. The production of isolated samples of both spin isomers is demonstrated in pure beams of para and ortho water in their respective absolute ground state. These single-quantum-state samples are ideal targets for unraveling spin-conversion mechanisms, for precision spectroscopy and fundamental symmetry-breaking studies, and for spin-enhanced applications, for example laboratory astrophysics and astrochemistry or hypersensitized NMR experiments. PMID:25196938

  9. Mensaje para alumnos y padres

    NASA Video Gallery

    El astronauta de la NASA José Hernández alienta a los estudiantes a que sigan sus sueños. Hernández también habla acerca del papel que juegan los padres para ayudar a que sus hijos hagan realidad s...

  10. Modelizacion, control e implementacion de un procesador energetico paralelo para aplicacion en sistemas multisalida

    NASA Astrophysics Data System (ADS)

    Ferreres Sabater, Agustin

    Cualquier sistema electronico que incluya un procesado o tratamiento de la senal, y ademas, algun tipo de actuador mecanico generalmente necesita, como minimo, dos tensiones diferentes de alimentacion. Excluyendo los sistemas de alimentacion distribuida, la solucion tecnica mas utilizada para proporcionar dos o mas tensiones consiste en las fuentes de alimentacion multisalida. En una fuente de alimentacion multisalida los diferentes circuitos que conforman cada salida comparten un mismo transformador de potencia optimizando coste, masa, y volumen. Las ventajas obtenidas con este procedimiento tienen en su contra el efecto que sobre cada salida individual provocan las demas en su conjunto debido, principalmente, a los efectos de los elementos parasitos de los componentes. Un cambio de carga en una de las salidas produce un transitorio que es visto por todas las demas como un efecto de impedancia cruzada, y al final del transitorio, la tension de cada salida es diferente respecto a la que tenian antes del transitorio. Este ultimo resultado se conoce como regulacion cruzada. La disminucion de los efectos de la regulacion cruzada ha sido objeto de estudio durante los ultimos anos. El objetivo ha sido el desarrollo de distintas estrategias que permiten, desde disminuir los efectos de la regulacion cruzada hasta los niveles deseables, a eliminarla completamente. El resultado final suele suponer una penalizacion sobre el diseno del sistema directamente proporcional al grado de regulacion a conseguir en las distintas salidas. Entre las soluciones propuestas para eliminar la regulacion cruzada las tecnicas de post-regulacion se han consolidado como la opcion mas aceptada ya que, pueden aplicarse a cualquier convertidor y no suponen ninguna complejidad adicional a la hora de plantear el diseno. En esta Tesis Doctoral se abordara el estudio de la tecnica conocida como postregulacion mediante transformador controlado, que si bien se ha empleado en convertidores resonantes, su

  11. La Provision de una Igualdad de Oportunidades Educativas para los Estudiantes con Conocimientos Limitados del Idioma Ingles (The Provision of an Equal Education Opportunity to Limited English Proficient Students).

    ERIC Educational Resources Information Center

    Office for Civil Rights (ED), Washington, DC.

    This federal policy statement outlines policy on provision of education to limited-English-speaking school children. First, it describes briefly the demographics of this population and the academic difficulties faced by them, and the recent federal initiative for broadened educational opportunity, America 2000: An Education Strategy. Then,…

  12. La implantacion del enfoque constructivista en el aula de ciencia: Estudio de caso multiple

    NASA Astrophysics Data System (ADS)

    Arroyo Betancourt, Luz I.

    Esta investigacion estudia la implantacion del enfoque constructivista en tres aulas de ciencia del contexto puertorriqueno. Se auscultaron las practicas educativas que utilizan maestras consideradas constructivistas y la correspondencia de sus practicas educativas con los elementos esenciales de la didactica que proponen los teoricos de los planteamientos constructivistas. Se ausculto, ademas, a que vision del enfoque constructivista responden las expresiones de las maestras acerca de su practica educativa y como compara con su quehacer, a la luz de los elementos esenciales de las visiones constructivistas piagetiana, social y radical. Se utilizo el diseno de estudio descriptivo de caso multiple. El estudio se baso en entrevistas a profundidad, revision de documentos y observacion no participativa a la sala de clases. El contexto fueron tres escuelas publicas de la Region Educativa de San Juan, una elemental, una intermedia y una superior. Los resultados confirmaron que la transicion hacia el enfoque constructivista es un proceso que toma tiempo, dedicacion y la participacion en adiestramientos y readiestramientos acerca del nuevo enfoque. Las maestras coinciden en la mayoria de las practicas educativas que utilizan para implantar el enfoque constructivista de ensenanza y difieren en algunas debido, probablemente, a que han tenido que adaptarlas a los correspondientes niveles de ensenanza: elemental, intermedio y superior. Dos de las maestras planifican por conceptos generadores, mientras que una de ellas planifica siguiendo la guia que recibe del Departamento de Educacion. Difieren ademas, en el enfasis que confieren al inquirir cientifico. Con relacion a la correspondencia entre la vision manifestada por las maestras a la luz de las visiones piagetiana, social y radical, aparentemente, las preguntas del protocolo de entrevistas no lograron evocar la informacion con suficiente profundidad, por lo que la investigadora tuvo que inferir las visiones de las

  13. Functional Expression of Drosophila para Sodium Channels

    PubMed Central

    Warmke, Jeffrey W.; Reenan, Robert A.G.; Wang, Peiyi; Qian, Su; Arena, Joseph P.; Wang, Jixin; Wunderler, Denise; Liu, Ken; Kaczorowski, Gregory J.; Ploeg, Lex H.T. Van der; Ganetzky, Barry; Cohen, Charles J.

    1997-01-01

    The Drosophila para sodium channel α subunit was expressed in Xenopus oocytes alone and in combination with tipE, a putative Drosophila sodium channel accessory subunit. Coexpression of tipE with para results in elevated levels of sodium currents and accelerated current decay. Para/TipE sodium channels have biophysical and pharmacological properties similar to those of native channels. However, the pharmacology of these channels differs from that of vertebrate sodium channels: (a) toxin II from Anemonia sulcata, which slows inactivation, binds to Para and some mammalian sodium channels with similar affinity (Kd ≅ 10 nM), but this toxin causes a 100-fold greater decrease in the rate of inactivation of Para/TipE than of mammalian channels; (b) Para sodium channels are >10-fold more sensitive to block by tetrodotoxin; and (c) modification by the pyrethroid insecticide permethrin is >100-fold more potent for Para than for rat brain type IIA sodium channels. Our results suggest that the selective toxicity of pyrethroid insecticides is due at least in part to the greater affinity of pyrethroids for insect sodium channels than for mammalian sodium channels. PMID:9236205

  14. Laparoscopic extraperitoneal para-aortic lymphadenectomy

    PubMed Central

    Iserte, Pablo Padilla; Minig, Lucas; Zorrero, Cristina

    2015-01-01

    Lymph nodes are the main pathway in the spread of gynaecological malignancies, being a well-known prognostic factor. Lymph node dissection is a complex surgical procedure and requires surgical expertise to perform the procedure, thereby minimising complications. In addition, lymphadenectomy has value in the diagnosis, prognosis, and treatment of patients with gynaecologic cancer. Therefore, a video focused on the para-aortic retroperitoneal anatomy and the surgical technique of the extraperitoneal para-aortic lymphadenectomy is presented. PMID:26435746

  15. Projeto do sistema anti-ressonante da fiação dos transdutores para o detector Mario Schenberg

    NASA Astrophysics Data System (ADS)

    Vieira, S. J.., Jr.; Melo, J. L.

    2003-08-01

    O detector de ondas gravitacionais Mario Schenberg está sendo projetado e construído pelo grupo Gráviton. Sua construção está ocorrendo no Laboratório de Estado Sólido e Baixas Temperaturas (LESBT) da Universidade de São Paulo, na cidade de São Paulo. Esse detector possui uma massa ressonante esférica de cobre-alumínio, com 65 cm de diâmetro, pesando aproximadamente 1150 Kg, suspensa por um sistema de isolamento vibracional, que se encontra em fase de testes preliminares. A real eficácia desse sistema, entretanto, só poderá ser comprovada quando o detector estiver aparelhado com, pelo menos, um transdutor eletromecânico de altíssima sensibilidade acoplado à massa ressonante. Neste momento, não só este sistema de isolamento vibracional será posto em teste, como o do projeto da fiação que transporta os sinais de microondas até os transdutores e destes para a pré-amplificação. Apesar dessa fiação ter sido projetada para não apresentar nenhum contato com a superfície esférica da antena, de maneira a não haver nenhuma transmissão de ruído vibracional do laboratório para esta, deve-se minimizar o ruído microfônico produzido nessa fiação por oscilações mecânicas, uma vez que ela não utiliza nenhum sistema de isolamento vibracional. Com o intuito de resolver este problema, projetamos uma estrutura, formada por pequenos cilindros conectados por barras, a qual não terá nenhuma ressonância mecânica na faixa de freqüências de interesse para detecção (3000 - 3400 Hz). Desta forma, as vibrações nessa faixa não serão amplificadas. O projeto foi feito usando iterativamente, de maneira a otimizar os resultados obtidos, o programa de elementos finitos Msc/Nastran. Através de simulações feitas neste programa, determinamos os parâmetros geométricos ideais a serem utilizados, os quais proporcionam a maior região espectral de interesse livre de ressonâncias.

  16. Process for para-ethyltoluene dehydrogenation

    SciTech Connect

    Chu, C.C.

    1986-06-03

    A process is described of dehydrogenating para-ethyltoluene to selectively form para-methylstyrene comprising contacting to para-ethyltoluene under dehydrogenation reaction conditions with a catalyst composition comprising: (a) from about 30% to 60% by weight of iron oxide, calculated as ferric oxide; (b) from about 13% to 48% by weight of a potassium compound, calculated as potassium oxide; and (c) from about 0% to 5% by weight of a chromium compound, calculated as chromic oxide. The improvement is described comprising dehydrogenating the para-ethyltoluene with a catalyst composition comprising, in addition to the components (a), (b) and (c), a modifying component (d) capable of rendering the para-methylstyrene-containing dehydrogenation reaction effluent especially resistant to the subsequent formation of popcorn polymers when the dehydrogenation of para-ethyltoluene is conducted over the modified catalyst, the modifying component (d) being a bismuth compound present to the extent of from about 1% to 20% by weight of the catalyst composition, calculated as bismuth trioxide.

  17. 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.

  18. The ParaScope parallel programming environment

    NASA Technical Reports Server (NTRS)

    Cooper, Keith D.; Hall, Mary W.; Hood, Robert T.; Kennedy, Ken; Mckinley, Kathryn S.; Mellor-Crummey, John M.; Torczon, Linda; Warren, Scott K.

    1993-01-01

    The ParaScope parallel programming environment, developed to support scientific programming of shared-memory multiprocessors, includes a collection of tools that use global program analysis to help users develop and debug parallel programs. This paper focuses on ParaScope's compilation system, its parallel program editor, and its parallel debugging system. The compilation system extends the traditional single-procedure compiler by providing a mechanism for managing the compilation of complete programs. Thus, ParaScope can support both traditional single-procedure optimization and optimization across procedure boundaries. The ParaScope editor brings both compiler analysis and user expertise to bear on program parallelization. It assists the knowledgeable user by displaying and managing analysis and by providing a variety of interactive program transformations that are effective in exposing parallelism. The debugging system detects and reports timing-dependent errors, called data races, in execution of parallel programs. The system combines static analysis, program instrumentation, and run-time reporting to provide a mechanical system for isolating errors in parallel program executions. Finally, we describe a new project to extend ParaScope to support programming in FORTRAN D, a machine-independent parallel programming language intended for use with both distributed-memory and shared-memory parallel computers.

  19. Oxidative para-triflation of acetanilides.

    PubMed

    Pialat, Amélie; Liégault, Benoît; Taillefer, Marc

    2013-04-01

    Direct triflation of acetanilide derivatives with silver triflate has been accomplished under mild iodine(III)-mediated oxidative conditions. The reaction shows excellent regioselectivity for the para position and tolerates a range of ortho and meta substituents on the aromatic ring. This method is also compatible with the preparation of arylnonaflates in synthetically useful yields. PMID:23534500

  20. FDA aprueba la primera inmunoterapia para linfoma

    Cancer.gov

    La FDA ha aprobado nivolumab (Opdivo®) para el tratamiento de pacientes con el linfoma clásico de Hodgkin que ha recaído o empeorado después de recibir un trasplante autólogo hematopoyético seguido de brentuximab vedotin (Adcetris®)

  1. Centro para la Salud Mundial (CGH) del NCI

    Cancer.gov

    El Centro para la Salud Mundial (CGH) del NCI coordina actividades de investigación y trabaja con socios nacionales e internacionales para comprender y enfrentar la carga que representa el cáncer a nivel mundial.

  2. Para-hydrogen perspectives in hyperpolarized NMR.

    PubMed

    Glöggler, Stefan; Colell, Johannes; Appelt, Stephan

    2013-10-01

    The first instance of para-hydrogen induced polarization (PHIP) in an NMR experiment was serendipitously observed in the 1980s while investigating a hydrogenation reaction (Seldler et al., 1983; Bowers and Weitekamp, 1986, 1987; Eisenschmid et al., 1987) [1-4]. Remarkably a theoretical investigation of the applicability of para-hydrogen as a hyperpolarization agent was being performed in the 1980's thereby quickly providing a theoretical basis for the PHIP-effect (Bowers and Weitekamp, 1986) [2]. The discovery of signal amplification by a non-hydrogenating interaction with para-hydrogen has recently extended the interest to exploit the PHIP effect, as it enables investigation of compounds without structural alteration while retaining the advantages of spectroscopy with hyperpolarized compounds [5]. In this article we will place more emphasis of the future applications of the method while only briefly discussing the efforts that have been made in the understanding of the phenomenon and the development of the method so far. PMID:23932399

  3. Allergic contact dermatitis to para-phenylenediamine.

    PubMed

    Jenkins, David; Chow, Elizabeth T

    2015-02-01

    Exposure to hair dye is the most frequent route of sensitisation to para-phenylenediamine (PPD), a common contact allergen. International studies have examined the profile of PPD, but Australian-sourced information is lacking. Patients are often dissatisfied with advice to stop dyeing their hair. This study examines patients' characteristics, patch test results and outcomes of PPD allergy from a single Australian centre, through a retrospective analysis of patch test data from 2006 to 2013 at the Liverpool Hospital Dermatology Department. It reviews the science of hair dye allergy, examines alternative hair dyes and investigates strategies for hair dyeing. Of 584 patients, 11 were allergic to PPD. Our PPD allergy prevalence rate of 2% is at the lower end of international reported rates. About half these patients also react to para-toluenediamine (PTD). Affected patients experience a significant lifestyle disturbance. In all, 78% tried alternative hair dyes after the patch test diagnosis and more than half continued to dye their hair. Alternative non-PPD hair dyes are available but the marketplace can be confusing. Although some patients are able to tolerate alternative hair dyes, caution is needed as the risk of developing an allergy to other hair dye ingredients, especially PTD, is high. PMID:25302475

  4. On Lightlike Geometry of Para-Sasakian Manifolds

    PubMed Central

    Acet, Bilal Eftal; Kılıç, Erol

    2014-01-01

    We study lightlike hypersurfaces of para-Sasakian manifolds tangent to the characteristic vector field. In particular, we define invariant lightlike hypersurfaces and screen semi-invariant lightlike hypersurfaces, respectively, and give examples. Integrability conditions for the distributions on a screen semi-invariant lightlike hypersurface of para-Sasakian manifolds are investigated. We obtain a para-Sasakian structure on the leaves of an integrable distribution of a screen semi-invariant lightlike hypersurface. PMID:24892072

  5. Consentimiento informado: una praxis dialogica para la investigacion

    PubMed Central

    Mondragon-Barrios, Liliana

    2009-01-01

    El consentimiento informado es un proceso, en el que una persona acepta participar en una investigation, conociendo los riesgos, beneficios, consecuencias o problemas que se puedan presenter durante el desarrollo de la misma. El objetivo de este trabajo es reunir las caracteristicas del proceso de consentimiento informado (PCI) pare que su discernimiento y cumplimiento posibilite el ejercicio etc° dialogico, reflexivo y responsable del investigador. Se presentan los resultados de una extensa revision de les elementos del PCI, desde sus cornponentes hasta su fundamento etico y legal, incluyendo los mites y realidades que existen sobre el formato de consentimiento informado come recurso legal de protection. El consentimiento informado no es un formato establecido que los investigadores repliquen, se trata de que la praxis del PCI sea una tarea cotidiana dentro de la investigation con seres humanos, como comunicaciOn deliberative y critica, responsable y comprometida entre dos agentes morales, investigador-investigado. PMID:19507477

  6. Dipolar induced para-hydrogen-induced polarization.

    PubMed

    Buntkowsky, Gerd; Gutmann, Torsten; Petrova, Marina V; Ivanov, Konstantin L; Bommerich, Ute; Plaumann, Markus; Bernarding, Johannes

    2014-01-01

    Analytical expressions for the signal enhancement in solid-state PHIP NMR spectroscopy mediated by homonuclear dipolar interactions and single pulse or spin-echo excitation are developed and simulated numerically. It is shown that an efficient enhancement of the proton NMR signal in solid-state NMR studies of chemisorbed hydrogen on surfaces is possible. Employing typical reaction efficacy, enhancement-factors of ca. 30-40 can be expected both under ALTADENA and under PASADENA conditions. This result has important consequences for the practical application of the method, since it potentially allows the design of an in-situ flow setup, where the para-hydrogen is adsorbed and desorbed from catalyst surfaces inside the NMR magnet. PMID:25218522

  7. Cooling by Para-to-Ortho-Hydrogen Conversion

    NASA Technical Reports Server (NTRS)

    Sherman, A.; Nast, T.

    1983-01-01

    Catalyst speeds conversion, increasing capacity of solid hydrogen cooling system. In radial-flow catalytic converter, para-hydrogen is converted to equilibrium mixture of para-hydrogen and ortho-hydrogen as it passes through porous cylinder of catalyst. Addition of catalyst increases capacity of hydrogen sublimation cooling systems for radiation detectors.

  8. Requisitos para utilizar el enlace | Smokefree Español

    Cancer.gov

    Espanol.smokefree.gov ofrece apoyo y recursos para norteamericanos que hablan español y quieren dejar de fumar. Este sitio en la red fue creada por la División de Investigación para el Control del Tabaco del Instituto Nacional del Cáncer.

  9. Construction of a Para-Ortho Hydrogen Test Cryostat

    NASA Astrophysics Data System (ADS)

    Essler, J.; Haberstroh, Ch.

    2010-04-01

    In a prospective hydrogen economy it is necessary to verify the para concentration of the employed hydrogen. In case of a short storage time of about a few days only it has been shown that a partial conversion into para-hydrogen gives an optimized overall efficiency. Hence, an easy and reliable method of measuring the para-hydrogen concentration is needed. In this paper, the concept and construction of a small test cryostat are described and first results are presented. The measuring principle is based on a catalytic induced adiabatic ortho-para conversion of a hydrogen gas flow starting from a known temperature. The operation of the system only requires a certain amount of liquid nitrogen as coolant. To determine the concentration of para-hydrogen it is only necessary to measure the temperature of the gas before and after the adiabatic catalyst cell. The measuring cryostat is used for further investigation of the spontaneous para-ortho conversion in the supercritical state. In addition, the design of the cryostat allows the investigation of different catalyst materials regarding the catalytic activity and possible degradation by using a known para concentration for the measurement.

  10. a New Equation of State for Solid para-HYDROGEN

    NASA Astrophysics Data System (ADS)

    Wang, Lecheng; Le Roy, Robert J.; Roy, Pierre-Nicholas

    2015-06-01

    Solid para-H_2 is a popular accommodating host for impurity spectroscopy due to its unique softness and the spherical symmetry of para-H_2 in its J}=0 rotational level. To simulate the properties of impurity-doped solid para-H_2, a reliable model for the `soft' pure solid para-H_2 at different pressures is highly desirable. While a couple of experimental and theoretical studies aimed at elucidating the equation of state (EOS) of solid para-H_2 have been reported, the calculated EOS was shown to be heavily dependent on the potential energy surface (PES) between two para-H_2 that was used in the simulations. The current study also demonstrates that different choices of the parameters governing the Quantum Monte Carlo simulation could produce different EOS curves. To obtain a reliable model for pure solid para-H_2, we used a new 1-D para-H_2 PES reported by Faruk et al. that was obtained by averaging over Hinde's highly accurate 6-D H_2--H_2 PES. The EOS of pure solid para-H_2 was calculated using the PIMC algorithm with periodic boundary conditions (PBC). To precisely determine the equilibrium density of solid para-H_2, both the value of the PIMC time step (τ) and the number of particles in the PBC cell were extrapolated to convergence. The resulting EOS agreed well with experimental observations, and the hcp structured solid para-H_2 was found to be more stable than the fcc one at 4.2K, in agreement with experiment. The vibrational frequency shift of para-H_2 as a function of the density of the pure solid was also calculated, and the value of the shift at the equilibrium density is found to agree well with experiment. T. Momose, H. Honshina, M. Fushitani and H. Katsuki, Vib. Spectrosc. 34, 95(2004). M. E. Fajardo, J. Phys. Chem. A 117, 13504 (2013). I. F. Silvera, Rev. Mod. Phys. 52, 393(1980). F. Operetto and F. Pederiva, Phys. Rev. B 73, 184124(2006). T. Omiyinka and M. Boninsegni, Phys. Rev. B 88, 024112(2013). N. Faruk, M. Schmidt, H. Li, R. J. Le Roy, and P

  11. ParaDiS-FEM dislocation dynamics simulation code primer

    SciTech Connect

    Tang, M; Hommes, G; Aubry, S; Arsenlis, A

    2011-09-27

    The ParaDiS code is developed to study bulk systems with periodic boundary conditions. When we try to perform discrete dislocation dynamics simulations for finite systems such as thin films or cylinders, the ParaDiS code must be extended. First, dislocations need to be contained inside the finite simulation box; Second, dislocations inside the finite box experience image stresses due to the free surfaces. We have developed in-house FEM subroutines to couple with the ParaDiS code to deal with free surface related issues in the dislocation dynamics simulations. This primer explains how the coupled code was developed, the main changes from the ParaDiS code, and the functions of the new FEM subroutines.

  12. Cooling by conversion of para to ortho-hydrogen

    NASA Technical Reports Server (NTRS)

    Sherman, A. (Inventor)

    1983-01-01

    The cooling capacity of a solid hydrogen cooling system is significantly increased by exposing vapor created during evaporation of a solid hydrogen mass to a catalyst and thereby accelerating the endothermic para-to-ortho transition of the vapor to equilibrium hydrogen. Catalyst such as nickel, copper, iron or metal hydride gels of films in a low pressure drop catalytic reactor are suitable for accelerating the endothermic para-to-ortho conversion.

  13. Para hydrogen equilibration in the atmospheres of the outer planets

    NASA Technical Reports Server (NTRS)

    Conrath, Barney J.

    1986-01-01

    The thermodynamic behavior of the atmospheres of the Jovian planets is strongly dependent on the extent to which local thermal equilibration of the ortho and para states of molecular hydrogen is achieved. Voyager IRIS data from Jupiter imply substantial departures of the para hydrogen fraction from equilibrium in the upper troposphere at low latitudes, but with values approaching equilibrium at higher latitudes. Data from Saturn are less sensitive to the orth-para ratio, but suggest para hydrogen fractions near the equilibrium value. Above approximately the 200 K temperature level, para hydrogen conversion can enhance the efficiency of convection, resulting in a substantial increase in overturning times on all of the outer planets. Currently available data cannot definitively establish the ortho-para ratios in the atmospheres of Uranus and Neptune, but suggest values closer to local equilibrium than to the 3.1 normal ratio. Modeling of sub-millimeter wavelength measurements of these planets suggest thermal structures with frozen equilibrium lapse rates in their convective regions.

  14. 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.

  15. A Comparative Usage-Based Approach to the Reduction of the Spanish and Portuguese Preposition "Para"

    ERIC Educational Resources Information Center

    Gradoville, Michael Stephen

    2013-01-01

    This study examines the frequency effect of two-word collocations involving "para" "to," "for" (e.g. "fui para," "para que") on the reduction of "para" to "pa" (in Spanish) and "pra" (in Portuguese). Collocation frequency effects demonstrate that language speakers…

  16. ParaText : scalable text modeling and analysis.

    SciTech Connect

    Dunlavy, Daniel M.; Stanton, Eric T.; Shead, Timothy M.

    2010-06-01

    Automated processing, modeling, and analysis of unstructured text (news documents, web content, journal articles, etc.) is a key task in many data analysis and decision making applications. As data sizes grow, scalability is essential for deep analysis. In many cases, documents are modeled as term or feature vectors and latent semantic analysis (LSA) is used to model latent, or hidden, relationships between documents and terms appearing in those documents. LSA supplies conceptual organization and analysis of document collections by modeling high-dimension feature vectors in many fewer dimensions. While past work on the scalability of LSA modeling has focused on the SVD, the goal of our work is to investigate the use of distributed memory architectures for the entire text analysis process, from data ingestion to semantic modeling and analysis. ParaText is a set of software components for distributed processing, modeling, and analysis of unstructured text. The ParaText source code is available under a BSD license, as an integral part of the Titan toolkit. ParaText components are chained-together into data-parallel pipelines that are replicated across processes on distributed-memory architectures. Individual components can be replaced or rewired to explore different computational strategies and implement new functionality. ParaText functionality can be embedded in applications on any platform using the native C++ API, Python, or Java. The ParaText MPI Process provides a 'generic' text analysis pipeline in a command-line executable that can be used for many serial and parallel analysis tasks. ParaText can also be deployed as a web service accessible via a RESTful (HTTP) API. In the web service configuration, any client can access the functionality provided by ParaText using commodity protocols ... from standard web browsers to custom clients written in any language.

  17. Capacitacion de educadores para areas marginales--I: Caracteristicas y necesidades educativas de los ninos, jovenes y adultos en las poblaciones menos favorecidas, rurales y urbanas. Tercera edicion (Preparation of Educators for Marginal Areas--I: Educational Needs and Characteristics of Children, Youth and Adults in Disadvantaged Populations, Rural and Urban. Third Edition).

    ERIC Educational Resources Information Center

    Tedesco, Juan Carlos

    Forty percent of the families in Latin America have an income which does not provide essential necessities. Two-thirds of poor families live in the countryside, while the remainder reside in urban slums. The key variable in explaining poverty is education. Without education these families have irregular, unstable, and low paying employment…

  18. Una técnica para filtrar patrones de fringing

    NASA Astrophysics Data System (ADS)

    Ostrov, P. G.

    Se presenta una nueva técnica para filtrar los patrones de fringing producidos en los CCDs tipo RCA. El método consiste en construir un mapa con los ángulos de inclinación de las franjas en cada punto de la imagen. Este mapa es ulteriormente utilizado para alinear con el patrón de interferencia una ventana estrecha, sobre la que se aplica un filtro de mediana. Este procedimiento permite eliminar la mayor parte del ruido del patrón de fringing sin destruirlo.

  19. Hacer frente - Para la familia y los amigos

    Cancer.gov

    Si usted ayuda a su familiar o amigo durante el tratamiento del cáncer, usted es quien le cuida. Estar al cuidado de una persona con cáncer puede incluir muchas tensiones. Sugerencias para que se cuide usted cuando cuida a otros.

  20. Tumores cerebrales—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento de los tumores cerebrales, así como referencias a estudios clínicos, estadísticas y otros temas relacionados con estos tipos de cáncer.

  1. Linfoma—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del linfoma, así como referencias a estudios clínicos, investigación, estadísticas y otros temas relacionados con este tipo de cáncer.

  2. Analyzing and Visualizing Cosmological Simulations with ParaView

    SciTech Connect

    Woodring, Jonathan; Heitmann, Katrin; Ahrens, James P; Fasel, Patricia; Hsu, Chung-Hsing; Habib, Salman; Pope, Adrian

    2011-01-01

    The advent of large cosmological sky surveys - ushering in the era of precision cosmology - has been accompanied by ever larger cosmological simulations. The analysis of these simulations, which currently encompass tens of billions of particles and up to a trillion particles in the near future, is often as daunting as carrying out the simulations in the first place. Therefore, the development of very efficient analysis tools combining qualitative and quantitative capabilities is a matter of some urgency. In this paper, we introduce new analysis features implemented within ParaView, a fully parallel, open-source visualization toolkit, to analyze large N-body simulations. A major aspect of ParaView is that it can live and operate on the same machines and utilize the same parallel power as the simulation codes themselves. In addition, data movement is in a serious bottleneck now and will become even more of an issue in the future; an interactive visualization and analysis tool that can handle data in situ is fast becoming essential. The new features in ParaView include particle readers and a very efficient halo finder that identifies friends-of-friends halos and determines common halo properties, including spherical overdensity properties. In combination with many other functionalities already existing within ParaView, such as histogram routines or interfaces to programming languages like Python, this enhanced version enables fast, interactive, and convenient analyses of large cosmological simulations. In addition, development paths are available for future extensions.

  3. Cabozantinib y lenvatinib para cáncer renal

    Cancer.gov

    Artículo del blog del NCI sobre la aprobación reciente de la FDA de cabozantinib (Cabometyx®) y de lenvatinib (Lenvima®) para el tratamiento de pacientes cuyo cáncer avanzado de riñón ha evolucionado después de tratamiento con terapias antiangiogénicas.

  4. Leucemia—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento de la leucemia, así como referencias a estudios clínicos, investigación, estadísticas y otros temas relacionados con este tipo de cáncer.

  5. ACUTE TOXICITY OF PARA-NONYLPHENOL TO SALTWATER ANIMALS

    EPA Science Inventory

    ?para-Nonylphenol (PNP), a mixture of alkylphenols used in producing nonionic surfactants, is distributed widely in surface waters and aquatic sediments, where it can affect saltwater species. This article describes a database for acute toxicity of PNP derived for calculating a n...

  6. Analyzing and Visualizing Cosmological Simulations with ParaView

    NASA Astrophysics Data System (ADS)

    Woodring, Jonathan; Heitmann, Katrin; Ahrens, James; Fasel, Patricia; Hsu, Chung-Hsing; Habib, Salman; Pope, Adrian

    2011-07-01

    The advent of large cosmological sky surveys—ushering in the era of precision cosmology—has been accompanied by ever larger cosmological simulations. The analysis of these simulations, which currently encompass tens of billions of particles and up to a trillion particles in the near future, is often as daunting as carrying out the simulations in the first place. Therefore, the development of very efficient analysis tools combining qualitative and quantitative capabilities is a matter of some urgency. In this paper, we introduce new analysis features implemented within ParaView, a fully parallel, open-source visualization toolkit, to analyze large N-body simulations. A major aspect of ParaView is that it can live and operate on the same machines and utilize the same parallel power as the simulation codes themselves. In addition, data movement is in a serious bottleneck now and will become even more of an issue in the future; an interactive visualization and analysis tool that can handle data in situ is fast becoming essential. The new features in ParaView include particle readers and a very efficient halo finder that identifies friends-of-friends halos and determines common halo properties, including spherical overdensity properties. In combination with many other functionalities already existing within ParaView, such as histogram routines or interfaces to programming languages like Python, this enhanced version enables fast, interactive, and convenient analyses of large cosmological simulations. In addition, development paths are available for future extensions.

  7. Fatiga (PDQ®)—Versión para pacientes

    Cancer.gov

    Resumen de información revisada por expertos acerca de la fatiga, una afección caracterizada por extremo cansancio e incapacidad para funcionar por la falta de energía, que a menudo se observa como una complicación del cáncer y su tratamiento.

  8. Delirio (PDQ®)—Versión para pacientes

    Cancer.gov

    Resumen de información revisada por expertos acerca del delirio como una complicación del cáncer o su tratamiento. Se tratan enfoques de los cuidados médicos de apoyo y los abordajes farmacológicos para el manejo del delirio.

  9. Mesotelioma maligno—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento y las causas del mesotelioma maligno, así como referencias a estudios clínicos y otros temas relacionados con este tipo de cáncer.

  10. Retinoblastoma—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del retinoblastoma, así como referencias a estudios clínicos, estadísticas y otros temas relacionados con este tipo de cáncer.

  11. Neuroblastoma—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento y los exámenes de detección del neuroblastoma, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  12. 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.

  13. Sistemas Correctores de Campo Para EL Telescopio Cassegrain IAC80

    NASA Astrophysics Data System (ADS)

    Galan, M. J.; Cobos, F. J.

    1987-05-01

    El proyecto de instrumentación de mayor importancia que ha tenido el Instituto de Astrofisica de Canarias en los últimos afios ha sido el diseflo y construcción del te1escopio IAC8O. Este requería del esfuerzo con junto en mec´nica, óptica y electrónica, lo que facilitó la estructuración y el crecimiento de los respectivos grupos de trabajo, que posteriormente se integraron en departamentos En su origen (1977), el telescopio IAC80 fue concebido como un sistema clásico tipo Cassegrain, con una razón focal F/i 1.3 para el sistema Casse grain y una razón focal F/20 para el sistema Coudé. Posteriormente, aunque se mantuvo la filosofia de que el sistema básico fuera el F/11.3, se consideró conveniente el diseño de secundarios para razones focales F/16 y F/32, y se eliminó el de F/20. Sin embargo, dada la importancia relativa que un foco estrictamente fotográfico tiene en un telescopio moderno, diseñado básicamente para fotometría fotoeléctrica y con un campo util mínimamente de 40 minutos de arco, se decídió Ilevar a cabo el diseño de un secundario F/8 con un sistema corrector de campo, pero que estuviera formado únicamente por lentes con superficies esféricas para que asl su construcción fuera posible en España ó en México. La creciente utilización de detectores bidimensionales para fines de investigación astron6mica y la viabilidad de que en un futuro cercano éstos tengan un área sensible cada vez mayor, hicieron atractiva la idea de tener diseñado un sistema corrector de campo para el foco primario (F/3), con un campo útil mínimo de un grado, y también con la limitante de que sus componentes tuvieron sólamente supérficies esféricas. Ambos diseños de los sis-temas correctores de campo se llevaron a cabo, en gran medida, como parte de un proyecto de colaboración e intercambio en el área de diseño y evaluación de sistemas ópticos.

  14. DESIGN NOTE: A compact catalytic converter for the production of para-hydrogen

    NASA Astrophysics Data System (ADS)

    Juarez, A. M.; Cubric, D.; King, G. C.

    2002-05-01

    The design and operation of a compact converter to produce a constant flow of para-hydrogen from normal hydrogen is described. The converter features a paramagnetic compound (nickel sulfate) that catalyses the conversion of ortho- to para-hydrogen at temperatures of 14-21 K. The converter has been tested by measuring rotationally resolved photoelectron spectra in the para-hydrogen produced. The percentage of the para-hydrogen species in the converted gas was determined to be >97%.

  15. Control del dolor: Apoyo para las personas con cáncer

    Cancer.gov

    Contiene información sobre las medicinas contra el dolor para pacientes con cáncer, los planes para controlarlo, cómo hablar con su equipo de atención médica sobre el dolor que usted siente y qué hacer para controlar los efectos físicos y emocionales del

  16. ParA resolvase catalyzes site-specific excision of DNA from the Arabidopsis genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The small serine resolvase ParA from bacterial plasmids RK2 and RP4 catalyzes the recombination of two identical 133 bp recombination sites known as MRS. Previously, we reported that ParA is active in the fission yeast Schizosaccharomyces pombe. In this work, the parA recombinase gene was placed un...

  17. Forms of Appropriation of Tools for the Astronomy Education in Continuous Training of Teachers. (Spanish Title: Formas de Apropriación de Herramientas Para la Enseñanza de la Astronomía en la Formación Docente Continua.) Formas de Apropriação de Instrumentos Para o Ensino de Astronomia na Formação Continuada de Professores

    NASA Astrophysics Data System (ADS)

    Marques Soares, Leonardo; Sousa Nascimento, Silvania

    2012-07-01

    The main focus of this article is to present some impressions about the way some teachers appropriated of the tools from the ASTRONOMY TEACHING KIT (KITPEA). The subjects of this research were teachers that took part in the astronomy teaching specialization course offered by the Continuing Education Project (FOCO) at Math and Science Teaching Center (CECIMIG) from the School of Education of Federal University of Minas Gerais (FaE/UFMG). The data was collected with the use of a questionnaire and of an interview applied to these teachers. The analysis of the data was structured with the aid of the Activity Theory and the Mediated Action Theory. We interpret the teachers' speech using the constitutive aspects of the activity system and the concepts of appropriation and domain as an analytical device. It was possible to recognize the appropriation of the tools in 7 narratives among the 11 individuals who took part in the research. El objetivo principal de ese artículo es presentar indicaciones sobre la manera como algunos maestros se apropiaron de las herramientas del KIT PARA LA ENSEÑANZA DE LA ASTRONOMÍA (KITPEA). Los sujetos de esa investigación son docentes que participaron del curso de especialización en enseñanza de astronomía ofrecido por el Proyecto de Formación Continua (Foco) en el Centro de Enseñanza de Ciencias y Matemática (CECIMIG) de la Facultad de Educación de la Universidad Federal de Minas Gerais (FaE/UFMG). Recogimos las informaciones a través de un cuestionario y de una encuesta, aplicados a esos docentes. Estructuramos el análisis de esas informaciones con la ayuda de la Teoría de la Actividad y de la Teoría de la Acción Mediada. Interpretamos os discursos de los docentes usando como dispositivo analítico los elementos constitutivos del sistema de actividad y los conceptos apropiación y dominio. Entre los 11 sujetos que participaron de la investigación, fue posible interpretar con claridad la apropiación de las herramientas en

  18. The Regulation of para-Nitrophenol Degradation in Pseudomonas putida DLL-E4

    PubMed Central

    Chen, Qiongzhen; Tu, Hui; Luo, Xue; Zhang, Biying; Huang, Fei; Li, Zhoukun; Wang, Jue; Shen, Wenjing; Wu, Jiale; Cui, Zhongli

    2016-01-01

    Pseudomonas putida DLL-E4 can efficiently degrade para-nitrophenol and its intermediate metabolite hydroquinone. The regulation of para-nitrophenol degradation was studied, and PNP induced a global change in the transcriptome of P. putida DLL-E4. When grown on PNP, the wild-type strain exhibited significant downregulation of 2912 genes and upregulation of 845 genes, whereas 2927 genes were downregulated and 891 genes upregulated in a pnpR-deleted strain. Genes related to two non-coding RNAs (ins1 and ins2), para-nitrophenol metabolism, the tricarboxylic acid cycle, the outer membrane porin OprB, glucose dehydrogenase Gcd, and carbon catabolite repression were significantly upregulated when cells were grown on para-nitrophenol plus glucose. pnpA, pnpR, pnpC1C2DECX1X2, and pnpR1 are key genes in para-nitrophenol degradation, whereas pnpAb and pnpC1bC2bDbEbCbX1bX2b have lost the ability to degrade para-nitrophenol. Multiple components including transcriptional regulators and other unknown factors regulate para-nitrophenol degradation, and the transcriptional regulation of para-nitrophenol degradation is complex. Glucose utilization was enhanced at early stages of para-nitrophenol supplementation. However, it was inhibited after the total consumption of para-nitrophenol. The addition of glucose led to a significant enhancement in para-nitrophenol degradation and up-regulation in the expression of genes involved in para-nitrophenol degradation and carbon catabolite repression (CCR). It seemed that para-nitrophenol degradation can be regulated by CCR, and relief of CCR might contribute to enhanced para-nitrophenol degradation. In brief, the regulation of para-nitrophenol degradation seems to be controlled by multiple factors and requires further study. PMID:27191401

  19. Para rubber seed oil: new promising unconventional oil for cosmetics.

    PubMed

    Lourith, Nattaya; Kanlayavattanakul, Mayuree; Sucontphunt, Apirada; Ondee, Thunnicha

    2014-01-01

    Para rubber seed was macerated in petroleum ether and n-hexane, individually, for 30 min. The extraction was additionally performed by reflux and soxhlet for 6 h with the same solvent and proportion. Soxhlet extraction by petroleum ether afforded the greatest extractive yield (22.90 ± 0.92%). Although antioxidant activity by means of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay was insignificantly differed in soxhleted (8.90 ± 1.15%) and refluxed (9.02 ± 0.71%) by n-hexane, soxhlet extraction by n-hexane was significantly (p < 0.05) potent scavenged 2,2'-azino-bis(3-ethylbenzothaiazoline)-6-sulfonic acid) or ABTS radical with trolox equivalent antioxidant capacity (TEAC) of 66.54 ± 6.88 mg/100 g oil. This extract was non cytotoxic towards normal human fibroblast cells. In addition, oleic acid and palmitic acid were determined at a greater content than in the seed of para rubber cultivated in Malaysia, although linoleic and stearic acid contents were not differed. This bright yellow extract was further evaluated on other physicochemical characters. The determined specific gravity, refractive index, iodine value, peroxide value and saponification value were in the range of commercialized vegetable oils used as cosmetic raw material. Therefore, Para rubber seed oil is highlighted as the promising ecological ingredient appraisal for cosmetics. Transforming of the seed that is by-product of the important industrial crop of Thailand into cosmetics is encouraged accordingly. PMID:24976614

  20. TELEMEDICINA: UN DESAFÍO PARA AMÉRICA LATINA

    PubMed Central

    Litewka, Sergio

    2011-01-01

    La telemedicina es una tendencia creciente en la prestación de los servicios médicos. Aunque la eficacia de esta práctica no ha estado bien establecida, es probable que los países en desarrollo compartirán este nuevo paradigma con los desarrollados. Los defensores de la telemedicina en América Latina sostienen que será una herramienta útil para reducir las disparidades y mejorar la accesibilidad de atención de salud. Aunque América Latina quizá se convierta en un lugar para la investigación e investigación de estos procedimientos, no está claro cómo la telemedicina podría contribuir a mejorar la accesibilidad para las poblaciones desfavorecidas, o coexistir con sistemas de atención de salud públicos crónicamente enfermos. Telemedicine is a growing trend in the provision of medical services. Although the effectiveness of this practice has not been well established, it is likely that developing countries will share this new paradigm with developed ones. Supporters of telemedicine in Latin America maintain that it will be a useful tool for reducing disparities and improving health care accessibility. Although Latin America might become a place for research and investigation of these procedures, it is not clear how telemedicine could contribute to improving accessibility for disadvantaged populations, or coexist with chronically ill-funded public healthcare systems. PMID:21625326

  1. ParA resolvase catalyzes site-specific excision of DNA from the Arabidopsis genome.

    PubMed

    Thomson, James G; Yau, Yuan-Yeu; Blanvillain, Robert; Nunes, Wylla M; Chiniquy, Dawn; Thilmony, Roger; Ow, David W

    2009-04-01

    The small serine resolvase ParA from bacterial plasmids RK2 and RP4 catalyzes the recombination of two identical 133 bp recombination sites known as MRS. Previously, we reported that ParA is active in the fission yeast Schizosaccharomyces pombe. In this work, the parA recombinase gene was placed under the control of the Arabidopsis OXS3 promoter and introduced into Arabidopsis lines harboring a chromosomally integrated MRS-flanked target. The ParA recombinase excised the MRS-flanked DNA and the excision event was detected in subsequent generations in the absence of ParA, indicating germinal transmission of the excision event. The precise site-specific deletion by the ParA recombination system in planta demonstrates that the ParA recombinase can be used to remove transgenic DNA, such as selectable markers or other introduced transgenes that are no longer desired in the final product. PMID:18704739

  2. ORTHO-PARA SELECTION RULES IN THE GAS-PHASE CHEMISTRY OF INTERSTELLAR AMMONIA

    SciTech Connect

    Faure, A.; Hily-Blant, P.; Le Gal, R.; Rist, C.

    2013-06-10

    The ortho-para chemistry of ammonia in the cold interstellar medium is investigated using a gas-phase chemical network. Branching ratios for the primary reaction chain involved in the formation and destruction of ortho- and para-NH{sub 3} were derived using angular momentum rules based on the conservation of the nuclear spin. We show that the 'anomalous' ortho-to-para ratio of ammonia ({approx}0.7) observed in various interstellar regions is in fact consistent with nuclear spin selection rules in a para-enriched H{sub 2} gas. This ratio is found to be independent of temperature in the range 5-30 K. We also predict an ortho-to-para ratio of {approx}2.3 for NH{sub 2}. We conclude that a low ortho-to-para ratio of H{sub 2} naturally drives the ortho-to-para ratios of nitrogen hydrides below the statistical values.

  3. Laparoscopic para-aortic lymph node dissection for patients with primary colorectal cancer and clinically suspected para-aortic lymph nodes

    PubMed Central

    Song, Sung Ho; Park, Soo Yeun; Park, Jun Seok; Kim, Hye Jin; Yang, Chun-Seok

    2016-01-01

    Purpose Treatment of patients with para-aortic lymph node metastasis from colorectal cancer is controversial. The goal of this study was to investigate the technical feasibility of laparoscopic intrarenal para-aortic lymph node dissection in patients with colorectal cancer and clinically suspected para-aortic lymph node dissection. Methods The inclusion criteria for the laparoscopic approach were patients with infrarenal para-aortic lymph node metastasis from colorectal cancer. Patients who had any other distant metastatic lesion or metachronous para-aortic lymph node metastasis were excluded from this study. Perioperative outcomes and survival outcomes were analyzed. Results Between November 2004 and October 2013, 40 patients underwent laparoscopic para-aortic lymph node dissection. The mean operating time was 192.3 ± 68.8 minutes (range, 100-400 minutes) and the mean estimated blood loss was 65.6 ± 52.6 mL (range, 20-210 mL). No patient required open conversion. The postoperative complication rate was 15.0%. Sixteen patients (40.0%) had pathologically positive lymph nodes. In patients with metastatic para-aortic lymph nodes, the 3-year overall survival rate and disease-free survival rate were 65.7% and 40.2%, respectively. Conclusion The results of our study suggest that a laparoscopic approach for patients with colorectal cancer with metastatic para-aortic lymph nodes can be a reasonable option for selected patients. PMID:26793690

  4. Centro para la Salud Mundial del NCI anuncia becas de investigación para tecnologías portátiles

    Cancer.gov

    El Centro para la Salud Mundial del NCI (CGH) anunció el otorgamiento de subvenciones que apoyarán el desarrollo y la validación de tecnologías portátiles y de bajo costo para mejorar la detección temprana, el diagnóstico y el tratamiento del cáncer.

  5. TELEMEDICINA: UN DESAFÍO PARA AMÉRICA LATINA.

    PubMed

    Litewka, Sergio

    2005-01-01

    La telemedicina es una tendencia creciente en la prestación de los servicios médicos. Aunque la eficacia de esta práctica no ha estado bien establecida, es probable que los países en desarrollo compartirán este nuevo paradigma con los desarrollados. Los defensores de la telemedicina en América Latina sostienen que será una herramienta útil para reducir las disparidades y mejorar la accesibilidad de atención de salud. Aunque América Latina quizá se convierta en un lugar para la investigación e investigación de estos procedimientos, no está claro cómo la telemedicina podría contribuir a mejorar la accesibilidad para las poblaciones desfavorecidas, o coexistir con sistemas de atención de salud públicos crónicamente enfermos.Telemedicine is a growing trend in the provision of medical services. Although the effectiveness of this practice has not been well established, it is likely that developing countries will share this new paradigm with developed ones. Supporters of telemedicine in Latin America maintain that it will be a useful tool for reducing disparities and improving health care accessibility. Although Latin America might become a place for research and investigation of these procedures, it is not clear how telemedicine could contribute to improving accessibility for disadvantaged populations, or coexist with chronically ill-funded public healthcare systems. PMID:21625326

  6. Amazon Land Wars in the South of Para

    NASA Technical Reports Server (NTRS)

    Simmons, Cynthia S.; Walker, Robert T.; Arima, Eugenio Y.; Aldrich, Stephen P.; Caldas, Marcellus M.

    2007-01-01

    The South of Para, located in the heart of the Brazilian Amazon, has become notorious for violent land struggle. Although land conflict has a long history in Brazil, and today impacts many parts of the country, violence is most severe and persistent here. The purpose of this article is to examine why. Specifically, we consider how a particular Amazonian place, the so-called South of Para has come to be known as Brazil's most dangerous badland. We begin by considering the predominant literature, which attributes land conflict to the frontier expansion process with intensified struggle emerging in the face of rising property values and demand for private property associated with capitalist development. From this discussion, we distill a concept of the frontier, based on notions of property rights evolution and locational rents. We then empirically test the persistence of place-based violence in the region, and assess the frontier movement through an analysis of transportation costs. The findings from the analyses indicate that the prevalent theorization of frontier violence in Amazonia does little to explain its persistent and pervasive nature in the South of Para. To fill this gap in understanding, we develop an explanation based the geographic conception of place, and we use contentious politics theory heuristically to elucidate the ways in which general processes interact with place specific history to engender a landscape of violence. In so doing, we focus on environmental, cognitive, and relational mechanisms (and implicated structures), and attempt to deploy them in an explanatory framework that allows direct observation of the accumulating layers of the region's tragic history. We end by placing our discussion within a political ecological context, and consider the implications of the Amazon Land War for the environment.

  7. RVA: A Plugin for ParaView 3.14

    SciTech Connect

    2015-09-04

    RVA is a plugin developed for the 64-bit Windows version of the ParaView 3.14 visualization package. RVA is designed to provide support in the visualization and analysis of complex reservoirs being managed using multi-fluid EOR techniques. RVA, for Reservoir Visualization and Analysis, was developed at the University of Illinois at Urbana-Champaign, with contributions from the Illinois State Geological Survey, Department of Computer Science and National Center for Supercomputing Applications. RVA was designed to utilize and enhance the state-of-the-art visualization capabilities within ParaView, readily allowing joint visualization of geologic framework and reservoir fluid simulation model results. Particular emphasis was placed on enabling visualization and analysis of simulation results highlighting multiple fluid phases, multiple properties for each fluid phase (including flow lines), multiple geologic models and multiple time steps. Additional advanced functionality was provided through the development of custom code to implement data mining capabilities. The built-in functionality of ParaView provides the capacity to process and visualize data sets ranging from small models on local desktop systems to extremely large models created and stored on remote supercomputers. The RVA plugin that we developed and the associated User Manual provide improved functionality through new software tools, and instruction in the use of ParaView-RVA, targeted to petroleum engineers and geologists in industry and research. The RVA web site (http://rva.cs.illinois.edu) provides an overview of functions, and the development web site (https://github.com/shaffer1/RVA) provides ready access to the source code, compiled binaries, user manual, and a suite of demonstration data sets. Key functionality has been included to support a range of reservoirs visualization and analysis needs, including: sophisticated connectivity analysis, cross sections through simulation results between

  8. Spectroscopy of Single Dibenzoterrylene Molecules in para-Dichlorobenzene.

    PubMed

    Verhart, Nico R; Müller, Mathias; Orrit, Michel

    2016-05-18

    We study single dibenzoterrylene (DBT) molecules embedded in 1,4-dichlorobenzene (para-dichlorobenzene, pDCB) at 1.2 K. Due to the relatively low melting point of pDCB (53 °C), this host-guest system can be easily prepared from the molten phase. Narrow linewidths, stable molecular lines and high saturation count rates of single DBT molecules were observed. For this reason, we consider this host-guest system a promising candidate for the study of interactions of single molecules with other small objects such as waveguides or nanoparticles. PMID:26840901

  9. RVA: A Plugin for ParaView 3.14

    Energy Science and Technology Software Center (ESTSC)

    2015-09-04

    RVA is a plugin developed for the 64-bit Windows version of the ParaView 3.14 visualization package. RVA is designed to provide support in the visualization and analysis of complex reservoirs being managed using multi-fluid EOR techniques. RVA, for Reservoir Visualization and Analysis, was developed at the University of Illinois at Urbana-Champaign, with contributions from the Illinois State Geological Survey, Department of Computer Science and National Center for Supercomputing Applications. RVA was designed to utilize andmore » enhance the state-of-the-art visualization capabilities within ParaView, readily allowing joint visualization of geologic framework and reservoir fluid simulation model results. Particular emphasis was placed on enabling visualization and analysis of simulation results highlighting multiple fluid phases, multiple properties for each fluid phase (including flow lines), multiple geologic models and multiple time steps. Additional advanced functionality was provided through the development of custom code to implement data mining capabilities. The built-in functionality of ParaView provides the capacity to process and visualize data sets ranging from small models on local desktop systems to extremely large models created and stored on remote supercomputers. The RVA plugin that we developed and the associated User Manual provide improved functionality through new software tools, and instruction in the use of ParaView-RVA, targeted to petroleum engineers and geologists in industry and research. The RVA web site (http://rva.cs.illinois.edu) provides an overview of functions, and the development web site (https://github.com/shaffer1/RVA) provides ready access to the source code, compiled binaries, user manual, and a suite of demonstration data sets. Key functionality has been included to support a range of reservoirs visualization and analysis needs, including: sophisticated connectivity analysis, cross sections through simulation results

  10. CYP96T1 of Narcissus sp. aff. pseudonarcissus Catalyzes Formation of the Para-Para' C-C Phenol Couple in the Amaryllidaceae Alkaloids

    PubMed Central

    Kilgore, Matthew B.; Augustin, Megan M.; May, Gregory D.; Crow, John A.; Kutchan, Toni M.

    2016-01-01

    The Amaryllidaceae alkaloids are a family of amino acid derived alkaloids with many biological activities; examples include haemanthamine, haemanthidine, galanthamine, lycorine, and maritidine. Central to the biosynthesis of the majority of these alkaloids is a C-C phenol-coupling reaction that can have para-para', para-ortho', or ortho-para' regiospecificity. Through comparative transcriptomics of Narcissus sp. aff. pseudonarcissus, Galanthus sp., and Galanthus elwesii we have identified a para-para' C-C phenol coupling cytochrome P450, CYP96T1, capable of forming the products (10bR,4aS)-noroxomaritidine and (10bS,4aR)-noroxomaritidine from 4′-O-methylnorbelladine. CYP96T1 was also shown to catalyzed formation of the para-ortho' phenol coupled product, N-demethylnarwedine, as less than 1% of the total product. CYP96T1 co-expresses with the previously characterized norbelladine 4′-O-methyltransferase. The discovery of CYP96T1 is of special interest because it catalyzes the first major branch in Amaryllidaceae alkaloid biosynthesis. CYP96T1 is also the first phenol-coupling enzyme characterized from a monocot. PMID:26941773

  11. Biodegradation of Para Amino Acetanilide by Halomonas sp. TBZ3

    PubMed Central

    Hajizadeh, Nader; Sefidi Heris, Youssof; Zununi Vahed, Sepideh; Vallipour, Javad; Hejazi, Mohammad Amin; Golabi, Sayyed Mahdi; Asadpour-Zeynali, Karim; Hejazi, Mohammad Saeid

    2015-01-01

    Background: Aromatic compounds are known as a group of highly persistent environmental pollutants. Halomonas sp. TBZ3 was isolated from the highly salty Urmia Lake of Iran. In this study, characterization of a new Halomonas isolate called Halomonas sp. TBZ3 and its employment for biodegradation of para-amino acetanilide (PAA), as an aromatic environmental pollutant, is described. Objectives: This study aimed to characterize the TBZ3 isolate and to elucidate its ability as a biodegradative agent that decomposes PAA. Materials and Methods: Primarily, DNA-DNA hybridization between TBZ3, Halomonas denitrificans DSM18045T and Halomonas saccharevitans LMG 23976T was carried out. Para-amino acetanilide biodegradation was assessed using spectrophotometry and confirmed by gas chromatography-mass spectroscopy (GC-MS). Parameters effective on biodegradation of PAA were optimized by the Response Surface Methodology (RSM). Results: The DNA-DNA hybridization experiments between isolate TBZ3, H. denitrificans and H. saccharevitans revealed relatedness levels of 57% and 65%, respectively. According to GC-MS results, TBZ3 degrades PAA to benzene, hexyl butanoate, 3-methyl-1-heptanol and hexyl hexanoate. Temperature 32.92°C, pH 6.76, and salinity 14% are the optimum conditions for biodegradation with a confidence level of 95% (at level α = 0.05). Conclusions: According to our results, Halomonas sp. TBZ3 could be considered as a biological agent for bioremediation of PAA and possibly other similar aromatic compounds. PMID:26495103

  12. A Proposed Activity for a Meaningful Learning about the Moon Phases. (Breton Title: Uma Proposta de Atividade Para a Aprendizagem Significativa sobre as Fases da Lua.) Una Actividad Propuesta Para EL Aprendizaje Significativo Acerca de Las Fases de la Luna

    NASA Astrophysics Data System (ADS)

    Martins, Bruno Andrade; Langhi, Rodolfo

    2012-12-01

    ínua avaliação durante o processo, culmina com a elaboração de uma história em quadrinhos envolvendo as fases da Lua. Portanto, o objetivo deste trabalho é apresentar uma proposta de atividade didática diferenciada sustentada pelos princípios teóricos da aprendizagem significativa aplicada ao ensino das fases da Lua durante as aulas de Física no ensino médio. En este trabajo se presenta uno de los contenidos de la Astronomía y el evidente fracaso en la enseñanza del tema en la escuela secundaria, a pesar del hecho que los documentos oficiales apuntan para la necesidad de trabajar contenidos de Astronomía en este nivel. Entre los conceptos alternativos en Astronomía que los alumnos secundarios llevan consigo, aún después de terminados los estudios, destacamos aquí el fenómeno de las fases de la Luna. El desarrollo de diferentes estrategias en relación con los métodos tradicionales, dirigidas al proceso de enseñanza-aprendizaje en este tema fue considerado en este trabajo como uno de los resultados obtenidos a la luz de los referenciales del aprendizaje significativo, tal como fueron fundamentados por Ausubel. Según la propuesta que aquí se presenta, la participación activa de los estudiantes en la ejecución de una actividad experimental y otras actividades educativas destinadas a la evaluación continua durante el proceso culminó en la elaboración de una historieta respecto de las fases de la Luna. Por lo tanto, el objetivo de este trabajo es presentar una propuesta de actividad de enseñanza diferenciada con el apoyo de los principios teóricos del aprendizaje significativo aplicado a la enseñanza de las fases de la luna durante las clases de física del ciclo secundario.

  13. Ortho-para mixing hyperfine interaction in the H2O+ ion and nuclear spin equilibration.

    PubMed

    Tanaka, Keiichi; Harada, Kensuke; Oka, Takeshi

    2013-10-01

    The ortho to para conversion of water ion, H2O(+), due to the interaction between the magnetic moments of the unpaired electron and protons has been theoretically studied to calculate the spontaneous emission lifetime between the ortho- and para-levels. The electron spin-nuclear spin interaction term, Tab(SaΔIb + SbΔIa) mixes ortho (I = 1) and para (I = 0) levels to cause the "forbidden" ortho to para |ΔI| = 1 transition. The mixing term with Tab = 72.0 MHz is 4 orders of magnitude higher for H2O(+) than for its neutral counterpart H2O where the magnetic field interacting with proton spins is by molecular rotation rather than the free electron. The resultant 10(8) increase of ortho to para conversion rate possibly makes the effect of conversion in H2O(+) measurable in laboratories and possibly explains the anomalous ortho to para ratio recently reported by Herschel heterodyne instrument for the far-infrared (HIFI) observation. Results of our calculations show that the ortho ↔ para mixings involving near-degenerate ortho and para levels are high (∼10(-3)), but they tend to occur at high energy levels, ∼300 K. Because of the rapid spontaneous emission, such high levels are not populated in diffuse clouds unless the radiative temperature of the environment is very high. The low-lying 101 (para) and 111 (ortho) levels of H2O(+) are mixed by ∼10(-4) making the spontaneous emission lifetime for the para 101 → ortho 000 transition 520 years and 5200 years depending on the F value of the hyperfine structure. Thus the ortho ↔ para conversion due to the unpaired electron is not likely to seriously affect thermalization of interstellar H2O(+) unless either the radiative temperature is very high or number density of the cloud is very low. PMID:23530629

  14. Pneumatic protection applied to an airbag for para-gliders

    NASA Astrophysics Data System (ADS)

    Raievski, V.; Valladas, G.

    1998-02-01

    We present a theory of pneumatic protection based on the laws of thermodynamics, elasticity and fluid mechanics. A general pneumatic protection system is made up of several communicating compartments, the differences in pressure of the compartments generating a transfer of mass and energy between them. The transfer offers interesting possibilities to improve the performance of the system. An example of this type of protection in aerial sport is the airbag for para-gliders, it is used in this paper to illustrate the theory. As the pressure in the airbag depends uniquely on its volume, the geometric model in the theory can be simplified. Experiments carried out with crash-test dummies equipped with sensors have confirmed the theoretical predictions.

  15. Spectroscopy of Defects in Epitaxially Grown Para-sexiphenyl Nanostructures

    NASA Astrophysics Data System (ADS)

    Kadashchuk, A.; Schols, S.; Skryshevski, Yu.; Beynik, I.; Teichert, C.; Hernandez-Sosa, G.; Sitter, H.; Andreev, A.; Frank, P.; Winkler, A.

    We present a study of steady-state- and time-resolved photoluminescence of para-sexiphenyl (PSP) films on KCl grown by organic molecular beam epitaxy (OMBE). Using different OMBE growth conditions has enabled us to vary greatly the morphology of the PSP crystallites but keeping virtually untouched their chemical structure. By this comparative study we prove that the broad red-shifted emission band has a structure-related origin rather than being due to monomolecular oxidative defects. The relative intensity of the defect emission band observed in the delayed spectra was found to be drastically suppressed in the OMBE-grown films dominated by growth mounds composed of upright standing molecules as opposed to the films consisting of crystallites formed by molecules lying parallel to the substrate.

  16. Para-Hydrogen-Enhanced Gas-Phase Magnetic Resonance Imaging

    SciTech Connect

    Bouchard, Louis-S.; Kovtunov, Kirill V.; Burt, Scott R.; Anwar,M. Sabieh; Koptyug, Igor V.; Sagdeev, Renad Z.; Pines, Alexander

    2007-02-23

    Herein, we demonstrate magnetic resonance imaging (MRI) inthe gas phase using para-hydrogen (p-H2)-induced polarization. A reactantmixture of H2 enriched in the paraspin state and propylene gas is flowedthrough a reactor cell containing a heterogenized catalyst, Wilkinson'scatalyst immobilized on modified silica gel. The hydrogenation product,propane gas, is transferred to the NMR magnet and is spin-polarized as aresult of the ALTADENA (adiabatic longitudinal transport and dissociationengenders net alignment) effect. A polarization enhancement factor of 300relative to thermally polarized gas was observed in 1D1H NMR spectra.Enhancement was also evident in the magnetic resonance images. This isthe first demonstration of imaging a hyperpolarized gaseous productformed in a hydrogenation reaction catalyzed by a supported catalyst.This result may lead to several important applications, includingflow-through porous materials, gas-phase reaction kinetics and adsorptionstudies, and MRI in low fields, all using catalyst-free polarizedfluids.

  17. ParaText : scalable text analysis and visualization.

    SciTech Connect

    Dunlavy, Daniel M.; Stanton, Eric T.; Shead, Timothy M.

    2010-07-01

    Automated analysis of unstructured text documents (e.g., web pages, newswire articles, research publications, business reports) is a key capability for solving important problems in areas including decision making, risk assessment, social network analysis, intelligence analysis, scholarly research and others. However, as data sizes continue to grow in these areas, scalable processing, modeling, and semantic analysis of text collections becomes essential. In this paper, we present the ParaText text analysis engine, a distributed memory software framework for processing, modeling, and analyzing collections of unstructured text documents. Results on several document collections using hundreds of processors are presented to illustrate the exibility, extensibility, and scalability of the the entire process of text modeling from raw data ingestion to application analysis.

  18. Nuevos sistemas de frecuencia intermedia para el IAR

    NASA Astrophysics Data System (ADS)

    Olalde, J. C.; Perilli, D.; Larrarte, J. J.

    Se presenta el diagrama en bloques de los nuevos sistemas de Frecuencia Intermedia para los dos radiómetros instalados en el IAR. Entre las características más importantes del sistema podemos mencionar la posibilidad de conectar cualquiera de las dos antenas a los ``backend" disponibles: analizador espectral de alta resolución (META II) de 0,05 Hz, autocorrelador de 1008 canales y contínuo. Se incorporan al sistema nuevos sintetizadores de frecuencia implementados con PLL y la moderna técnica de síntesis digital directa. Por último, el conjunto del sistema es susceptible de ser configurado por las computadoras de adquisición de datos, supervisadas por otra, que entrega el estado de funcionamiento actual y evita la selección de configuraciones incorrectas por parte del usuario.

  19. Wave intensity analysis of para-aortic counterpulsation.

    PubMed

    Lu, Pong-Jeu; Yang, Chi-Fu Jeffrey; Wu, Meng-Yu; Hung, Chun-Hao; Chan, Ming-Yao; Hsu, Tzu-Cheng

    2012-04-01

    Wave intensity analysis (WIA) was used to delineate and maximize the efficacy of a newly developed para-aortic blood pump (PABP). The intra-aortic balloon pump (IABP) was employed as the comparison benchmark. Acute porcine experiments using eight pigs, randomly divided into IABP (n = 4) and PABP (n = 4) groups, were conducted to compare the characteristics of intra- and para-aortic counterpulsation. We measured pressure and velocity with probes installed in the left anterior descending coronary artery and aorta, during and without PABP assistance. Wave intensity for aortic and left coronary waves were derived from pressure and flow measurements with synchronization correction applied. To achieve maximized support efficacy, deflation timings ranging from 25 ms ahead of to 35 ms after the R-wave were tested. Similar to those associated with IABP counterpulsation, the PABP-generated backward-traveling waves predominantly drove aortic and coronary blood flows. However, in contrast with IABP counterpulsation, the nonocclusive nature of the PABP allowed systolic unloading to be delayed into early systole, which resulted in near elimination of coronary blood steal without diminution of systolic left ventricular ejection wave intensities. WIA can elucidate subtleties among different counterpulsatile support means with high sensitivity. Total accelerating wave intensity (TAWI), which was defined as the sum of the time integration of accelerated parts of the positive and negative wave intensities, was used to quantify counterpulsation efficacy. In general, the larger the TAWI gain, the better the counter-pulsatile support efficacy. However, when PABP deflation timings were delayed to after the R-wave, the TAWI was found to be inversely correlated with coronary perfusion. In this delayed deflation timing setting, greater wave cancellation occurred, which led to decreased TAWI but increased coronary perfusion attributed to blood regurgitation reduction. PMID:22227124

  20. The parA resolvase performs site-specific genomic excision in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have designed a site-specific excision detection system in Arabidopsis to study the in planta activity of the small serine recombinase ParA. Using a transient expression assay as well as stable transgenic plant lines, we show that the ParA recombinase is catalytically active and capable of perfo...

  1. The Clearance of Creatinine, Inulin, Para-aminohippurate and Phenosulphothalein in the Cat

    PubMed Central

    Osbaldiston, G. W.; Fuhrman, W.

    1970-01-01

    Endogenous creatinine, inulin, para-amino-hippurate and phenolsulphothalein clearances for healthy cats are presented. The values for inulin and para-aminohippurate clearances (ml/kg/min) are similar to those for the dog. Creatinine clearance was less than inulin clearance values. Pnenolsulphothalein clearance may be a better index of glomerular rather than tubular function in the cat. PMID:4246836

  2. Chiral phosphoric acid catalyzed asymmetric addition of naphthols to para-quinone methides.

    PubMed

    Wong, Yuk Fai; Wang, Zhaobin; Sun, Jianwei

    2016-06-28

    An asymmetric addition of naphthols to in situ generated para-quinone methides catalyzed by a chiral phosphoric acid is described. A range of useful triarylmethanes can be generated from stable general para-hydroxybenzyl alcohols with good efficiency and enantioselectivity. PMID:26932597

  3. Para-meatal urethral cyst with bladder calculi: A case report and review of the literature.

    PubMed

    Patil, Siddangouda B; Patil, Nikhil Ashok; Kundargi, Vinay S; Biradar, Ashok N

    2015-01-01

    Para-meatal urethral cyst or median raphe cyst of the glans penis is a benign cystic lesion uncommonly encountered in prepubertal age group. Approximately, about 50 cases have been reported till date in the world literature. Herein we report a case of para-meatal urethral cyst concurrent with urinary bladder calculi. PMID:26539378

  4. Para-meatal urethral cyst with bladder calculi: A case report and review of the literature

    PubMed Central

    Patil, Siddangouda B.; Patil, Nikhil Ashok; Kundargi, Vinay S.; Biradar, Ashok N.

    2015-01-01

    Para-meatal urethral cyst or median raphe cyst of the glans penis is a benign cystic lesion uncommonly encountered in prepubertal age group. Approximately, about 50 cases have been reported till date in the world literature. Herein we report a case of para-meatal urethral cyst concurrent with urinary bladder calculi. PMID:26539378

  5. Under the skin: Biotransformation of para-aminophenol and para-phenylenediamine in reconstructed human epidermis and human hepatocytes.

    PubMed

    Nohynek, Gerhard J; Duche, Daniel; Garrigues, Alexia; Meunier, Pierre-Alain; Toutain, Herve; Leclaire, Jacques

    2005-09-15

    We investigated the biotransformation of the oxidative arylamine (AA) hair dye ingredients [14C]-para-aminophenol (PAP) and [14C]-para-phenylenediamine (PPD) in reconstructed human epidermis and human hepatocytes. Human epidermis quantitatively transformed PAP to its N-acetylated derivative (APAP), whereas hepatocytes transformed PAP to sulfate or glucuronic acid conjugates of APAP or PAP as well as free APAP. Epidermis and hepatocytes converted PPD to N-mono- (MAPPD) and N,N'-di-acetylated (DAPPD) derivatives. At higher concentrations of PPD (250-1000 microM), epidermis or hepatocytes produced more of the MAPPD, whereas concentrations below 250 microM and lower favoured formation of the DAPPD metabolite. When compared with epidermis, human hepatocytes had a three-fold or eight-fold greater capacity for generation of MAPPD or DAPPD, respectively. No evidence of transformation of PAP or PPD to N-hydroxylated derivatives was found in epidermis or hepatocytes. Our results suggest that (i) after dermal absorption of PAP or PPD, humans are systemically exposed to acetylated derivatives; (ii) current in vitro skin absorption studies may be inadapated for determination of human systemic exposure to AAs due to reduced or absent metabolic capacity of non-viable skin; (iii) due to qualitative differences between dermal and hepatic metabolism, oral toxicity studies may be unsuited for the hazard assessment of dermal exposure to AAs; and (iv) use of induced rodent liver S9 metabolic activation systems for in vitro genotoxicity studies may produce misleading results on the hazard of human dermal exposure to AAs. In conclusion, our data support the growing evidence that AAs are transformed in human skin and suggest that current practices of safety assessment of AAs should take these findings into account. PMID:15890478

  6. Contextual Factors that Foster or Inhibit Para-Teacher Professional Development: The Case of an Indian, Non-Governmental Organization

    ERIC Educational Resources Information Center

    Raval, Harini; McKenney, Susan; Pieters, Jules

    2012-01-01

    The appointment of para-professionals to overcome skill shortages and/or make efficient use of expensive resources is well established in both developing and developed countries. The present research concerns para-teachers in India. The literature on para-teachers is dominated by training for special needs settings, largely in developed societies.…

  7. Females prefer carotenoid colored males as mates in the pentamorphic livebearing fish, Poecilia parae.

    PubMed

    Bourne, Godfrey R; Breden, Felix; Allen, Teresa C

    2003-09-01

    The first results of female preference and chosen male mating success in a new model organism, the pentamorphic livebearing fish, Poecilia parae, are presented. Poecilia parae is a relative of the guppy, P. reticulata, and is assumed to have similar reproductive behavior. We tested the hypothesis that P. parae females, like female guppies, prefer carotenoid colored males as mates. Here we show that the time a female spent with males was significantly greater for carotenoid coloration in red and yellow melanzona, but time with these two morphs did not differ. The preferred red and yellow males mated significantly more often with their choosing females than did the non-preferred blue and parae males. The few blue melanzona and parae males that mated did so without performing courtship displays. Some females mated with all phenotypes including immaculata males during open group trials. Female P. parae clearly preferred males with carotenoid coloration, thereby corroborating the hypothesis. Alternative male mating tactics by blue melanzona, parae, and immaculata morphs and promiscuous mating by females also resembled features of reproductive behaviors exhibited by guppies. PMID:14504782

  8. Quantum fluctuations increase the self-diffusive motion of para-hydrogen in narrow carbon nanotubes.

    PubMed

    Kowalczyk, Piotr; Gauden, Piotr A; Terzyk, Artur P; Furmaniak, Sylwester

    2011-05-28

    Quantum fluctuations significantly increase the self-diffusive motion of para-hydrogen adsorbed in narrow carbon nanotubes at 30 K comparing to its classical counterpart. Rigorous Feynman's path integral calculations reveal that self-diffusive motion of para-hydrogen in a narrow (6,6) carbon nanotube at 30 K and pore densities below ∼29 mmol cm(-3) is one order of magnitude faster than the classical counterpart. We find that the zero-point energy and tunneling significantly smoothed out the free energy landscape of para-hydrogen molecules adsorbed in a narrow (6,6) carbon nanotube. This promotes a delocalization of the confined para-hydrogen at 30 K (i.e., population of unclassical paths due to quantum effects). Contrary the self-diffusive motion of classical para-hydrogen molecules in a narrow (6,6) carbon nanotube at 30 K is very slow. This is because classical para-hydrogen molecules undergo highly correlated movement when their collision diameter approached the carbon nanotube size (i.e., anomalous diffusion in quasi-one dimensional pores). On the basis of current results we predict that narrow single-walled carbon nanotubes are promising nanoporous molecular sieves being able to separate para-hydrogen molecules from mixtures of classical particles at cryogenic temperatures. PMID:21503294

  9. Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media

    DOEpatents

    Arnold, F.H.; Moore, J.C.

    1999-05-25

    A method is disclosed for isolating and identifying modified para-nitrobenzyl esterases which exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase. 43 figs.

  10. Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media

    DOEpatents

    Arnold, Frances H.; Moore, Jeffrey C.

    1999-01-01

    A method for isolating and identifying modified para-nitrobenzyl esterases which exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase.

  11. Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media

    DOEpatents

    Arnold, Frances H.; Moore, Jeffrey C.

    1998-01-01

    A method for isolating and identifying modified para-nitrobenzyl esterases which exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase.

  12. Para-nitrobenzyl esterases with enhanced activity in aqueous and nonaqueous media

    DOEpatents

    Arnold, F.H.; Moore, J.C.

    1998-04-21

    A method is disclosed for isolating and identifying modified para-nitrobenzyl esterases. These enzymes exhibit improved stability and/or esterase hydrolysis activity toward selected substrates and under selected reaction conditions relative to the unmodified para-nitrobenzyl esterase. The method involves preparing a library of modified para-nitrobenzyl esterase nucleic acid segments (genes) which have nucleotide sequences that differ from the nucleic acid segment which encodes for unmodified para-nitrobenzyl esterase. The library of modified para-nitrobenzyl nucleic acid segments is expressed to provide a plurality of modified enzymes. The clones expressing modified enzymes are then screened to identify which enzymes have improved esterase activity by measuring the ability of the enzymes to hydrolyze the selected substrate under the selected reaction conditions. Specific modified para-nitrobenzyl esterases are disclosed which have improved stability and/or ester hydrolysis activity in aqueous or aqueous-organic media relative to the stability and/or ester hydrolysis activity of unmodified naturally occurring para-nitrobenzyl esterase. 43 figs.

  13. Evidence for para dechlorination of polychlorobiphenyls by methanogenic bacteria

    SciTech Connect

    Ye, D.; Quensen, J.F.; Tiedje, J.M.

    1995-06-01

    When microorganisms eluted from upper Hudson River sediment were cultured without any substrate except polychlorobiphenyl (PCB)-free Hudson River sediment, methane formation was the terminal step of the anaerobic food chain. In sediments containing Aroclor 1242, addition of eubacterium-inhibiting antibiotics, which should have directly inhibited fermentative bacteria and thereby should have indirectly inhibited methanogens, resulted in no dechlorination activity or methane production. However, when substrates for methanogenic bacteria were provided along with the antibiotics (to free the methanogens from dependence on eubacteria), concomitant methane production and dechlorination of PCBs were observed. The dechlorination of Aroclor 1242 was from the para positions, a pattern distinctly different from, and more limited than, the pattern observed with untreated or pasteurized inocula. Both methane production and dechlorination in cultures amended with antibiotics plus methanogenic substrates were inhibited by 2-bromoethanesulfonic acid. These results suggest that the methanogenic bacteria are among the physiological groups capable of anaerobic dechlorination of PCBs, but that the dechlorination observed with methanogenic bacteria is less extensive than the dechlorination observed with more complex anaerobic consortia. 27 refs., 5 figs., 1 tab.

  14. Para-hydrogen induced polarization in heterogeneous hydrogenationreactions

    SciTech Connect

    Koptyug, Igor V.; Kovtunov, Kirill; Burt, Scott R.; Anwar, M.Sabieh; Hilty, Christian; Han, Song-I; Pines, Alexander; Sagdeev, Renad Z.

    2007-01-31

    We demonstrate the creation and observation ofpara-hydrogen-induced polarization in heterogeneous hydrogenationreactions. Wilkinson's catalyst, RhCl(PPh3)3, supported on eithermodified silica gel or a polymer, is shown to hydrogenate styrene intoethylbenzene and to produce enhanced spin polarizations, observed throughNMR, when the reaction was performed with H2 gas enriched in the paraspinisomer. Furthermore, gaseous phase para-hydrogenation of propylene topropane with two catalysts, the Wilkinson's catalyst supported onmodified silica gel and Rh(cod)(sulfos) (cod = cycloocta-1,5-diene;sulfos) - O3S(C6H4)CH2C(CH2PPh2)3) supported on silica gel, demonstratesheterogeneous catalytic conversion resulting in large spin polarizations.These experiments serve as a direct verification of the mechanism ofheterogeneous hydrogenation reactions involving immobilized metalcomplexes and can be potentially developed into a practical tool forproducing catalyst-free fluids with highly polarized nuclear spins for abroad range of hyperpolarized NMR and MRI applications.

  15. DYNA3D/ParaDyn Regression Test Suite Inventory

    SciTech Connect

    Lin, J I

    2011-01-25

    The following table constitutes an initial assessment of feature coverage across the regression test suite used for DYNA3D and ParaDyn. It documents the regression test suite at the time of production release 10.1 in September 2010. The columns of the table represent groupings of functionalities, e.g., material models. Each problem in the test suite is represented by a row in the table. All features exercised by the problem are denoted by a check mark in the corresponding column. The definition of ''feature'' has not been subdivided to its smallest unit of user input, e.g., algorithmic parameters specific to a particular type of contact surface. This represents a judgment to provide code developers and users a reasonable impression of feature coverage without expanding the width of the table by several multiples. All regression testing is run in parallel, typically with eight processors. Many are strictly regression tests acting as a check that the codes continue to produce adequately repeatable results as development unfolds, compilers change and platforms are replaced. A subset of the tests represents true verification problems that have been checked against analytical or other benchmark solutions. Users are welcomed to submit documented problems for inclusion in the test suite, especially if they are heavily exercising, and dependent upon, features that are currently underrepresented.

  16. Anise oil as para-methoxyamphetamine (PMA) precursor.

    PubMed

    Waumans, Dieter; Bruneel, Noël; Tytgat, Jan

    2003-04-23

    These days, MDMA is one of the most popular drugs of abuse. Due to its illegality, MDMA and its chemical precursors are watched by governmental organizations in many countries. To avoid conflicts with legal instances, underground chemists have tried to market several new unregulated amphetamine analogues, such as 4-MTA. Para-methoxyamphetamine (PMA), on the other hand, is regulated by law but its precursors are easily obtained since they are cheap and unwatched. This article presents such a case, namely the large scale synthesis of PMA using anethole, a main constituent of anise oil, as precursor. Anethole has been converted to its phenyl acetone analogue via peracid oxidation, while PMA itself has been synthesized using this ketone as precursor in the Leuckart synthesis. The synthesis of PMA using anethole as starting product has been investigated applying GC/MS and GC-HSPME/MS techniques, hereby discovering new specific (4-methoxyphenol) and already identified synthesis impurities (4-methyl-5-(4-methoxyphenyl)pyrimidine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzyl methyl ketimine, 1-(4-methoxyphenyl)-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, 1-(4-methoxyphenyl)-N-methyl-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzaldimine). The new impurity 4-methoxyphenol is specific for the application of a peracid oxidation method where anethole is used as precursor. PMID:12742705

  17. Metabolism of para-aminophenol by rat hepatocytes.

    PubMed

    Yan, Z; Nikelly, J G; Killmer, L; Tarloff, J B

    2000-08-01

    Autoxidation of para-aminophenol (PAP) has been proposed to account for the selective nephrotoxicity of this compound. However, other studies suggest that hepatic metabolites of PAP rather than the parent compound may be responsible for renal damage. These studies were designed to investigate PAP metabolism in isolated hepatocytes. We synthesized several proposed metabolites for analysis by HPLC/mass spectrometry and compared those results with HPLC/mass spectrometric analyses of metabolites found after incubating hepatocytes with PAP. Hepatocytes prepared from male Sprague-Dawley rats were incubated in Krebs-Henseleit buffer at 37 degrees C for 5 h with 2.3 mM PAP under an atmosphere of 5% CO2/95% O2. Aliquots were withdrawn at 0.1 h of incubation and then hourly through 5 h of incubation. Reactions were terminated by the addition of acetonitrile. Hepatocyte viability was unaltered with PAP present in the incubation medium. We found that hepatocytes converted PAP to two major metabolites (PAP-GSH conjugates and PAP-N-acetylcysteine conjugates) and several minor metabolites [PAP-O-glucuronide, acetaminophen (APAP), APAP-O-glucuronide, APAP-GSH conjugates, and 4-hydroxyformanilide]. Preincubating hepatoyctes with 1-aminobenzotriazole, an inhibitor of cytochromes P450, did not alter the pattern of PAP metabolism. In conclusion, we found that PAP was metabolized in hepatocytes predominantly to PAP-GSH conjugates and PAP-N-acetylcysteine conjugates in sufficient quantities to account for the nephrotoxicity of PAP. PMID:10901695

  18. Conformation of ionizable poly Para phenylene ethynylene in dilute solutions

    DOE PAGESBeta

    Wijesinghe, Sidath; Maskey, Sabina; Perahia, Dvora; Grest, Gary S.

    2015-11-03

    The conformation of dinonyl poly para phenylene ethynylenes (PPEs) with carboxylate side chains, equilibrated in solvents of different quality is studied using molecular dynamics simulations. PPEs are of interest because of their tunable electro-optical properties, chemical diversity, and functionality which are essential in wide range of applications. The polymer conformation determines the conjugation length and their assembly mode and affects electro-optical properties which are critical in their current and potential uses. The current study investigates the effect of carboxylate fraction on PPEs side chains on the conformation of chains in the dilute limit, in solvents of different quality. The dinonylmore » PPE chains are modeled atomistically, where the solvents are modeled both implicitly and explicitly. Dinonyl PPEs maintained a stretched out conformation up to a carboxylate fraction f of 0.7 in all solvents studied. The nonyl side chains are extended and oriented away from the PPE backbone in toluene and in implicit good solvent whereas in water and implicit poor solvent, the nonyl side chains are collapsed towards the PPE backbone. Thus, rotation around the aromatic ring is fast and no long range correlations are seen within the backbone.« less

  19. Uninfected Para-Anastomotic Aneurysms after Infrarenal Aortic Grafting

    PubMed Central

    Nano, Giovanni; Cusmai, Francesco; Ramponi, Fabio; Stegher, Silvia; Dell'Aglio, Daniela; Malacrida, Giovanni; Tealdi, Domenico G.

    2009-01-01

    Purpose This single-institution retrospective review examines the management of uninfected para-anastomotic aneurysms of the abdominal aorta (PAAA), developed after infrarenal grafting. Materials and Methods From October 1979 to November 2005, 31 PAAA were observed in our Department. Twenty-six uninfected PAAA of degenerative etiology, including 24 false and 2 true aneurysms, were candidates for intervention and retrospectively included in our database for management and outcome evaluation. Six (23%) patients were treated as emergencies. Surgery included tube graft interposition (n = 12), new reconstruction (n = 8), and graft removal with extra-anatomic bypass (n = 3). Endovascular management (n = 3) consisted of free-flow tube endografts. Results The mortality rate among the elective and emergency cases was 5% and 66.6%, respectively (p = 0.005). The morbidity rate in elective cases was 57.8%, whereas 75% in emergency cases (p = 0.99). The survival rate during the follow-up was significantly higher for elective cases than for emergency cases. Conclusion Uninfected PAAA is a late complication of aortic grafting, tends to evolve silently and is difficult to diagnose. The prevalence is underestimated and increases with time since surgery. The mortality rate is higher among patients treated as an emergency than among patients who undergo elective surgery, therefore, elective treatment and aggressive management in the case of pseudoaneurysm are the keys to obtain a good outcome. Endovascular treatment could reduce mortality. Patients who undergo infrarenal aortic grafting require life-long surveillance after surgery. PMID:19430556

  20. Para-Tyrosine Supplementation Improves Insulin- and Liraglutide- Induced Vasorelaxation in Cholesterol-Fed Rats.

    PubMed

    Sélley, Eszter; Kun, Szilárd; Kürthy, Mária; Kovács, Tibor; Wittmann, István; Molnár, Gergo A

    2015-01-01

    Former data of our workgroup indicated that the accumulation of oxidized amino acids (meta- and ortho-tyrosine) due to oxidative stress may play an important role in the impaired insulininduced vasoactive properties of different arterial segments. There are evidences, that incorporation of these amino acids into cellular proteins leads to certain hormonal resistances, which might be restored by supplementation with the physiologic isoform, para-tyrosine. Rats in the control group were kept on a regular diet, rats in the cholesterol-fed group received high-fat diet, while the third group of rats received high-fat diet with para-tyrosine supplementation for 16 weeks. Plasma cholesterol level was significantly higher in the cholesterol-fed group, while the level of cholesterol in the cholesterol+para-tyrosine group did not differ significantly from that of the controls. Plasma level of insulin after glucose stimulation was decreased in the cholesterol-fed group, while that in the para-tyrosine supplemented group did not differ significantly from the controls. Vascular para-, meta- and ortho-tyrosine content was measured with HPLC. Elevated vascular meta-tyrosine/para-tyrosine ratio of cholesterol fed rats could be avoided by para-tyrosine supplementation. Vascular response of the thoracic aorta to insulin and liraglutide was assessed by a DMT multi-myograph. Cholesterol feeding resulted in vascular insulin-and liraglutide resistance, which was restored by para-tyrosine supplementation. Incorporation of the oxidative stress induced pathological tyrosine isoforms leads to vascular-hormone-resistances. We show that the physiological amino acid para-tyrosine is capable of restoring hypercholesterolemia-induced increased meta-tyrosine content of the vascular wall, thus attenuating functional vascular damage. PMID:26202368

  1. Endovascular Treatment of a Ruptured Para-Anastomotic Aneurysm of the Abdominal Aorta

    SciTech Connect

    Sfyroeras, Giorgos S.; Lioupis, Christos Bessias, Nikolaos; Maras, Dimitris; Pomoni, Maria; Andrikopoulos, Vassilios

    2008-07-15

    We report a case of a ruptured para-anastomotic aortic aneurysm treated with implantation of a bifurcated stent-graft. A 72-year-old patient, who had undergone aortobifemoral bypass for aortoiliac occlusive disease 16 years ago, presented with a ruptured para-anastomotic aortic aneurysm. A bifurcated stent-graft was successfully deployed into the old bifurcated graft. This is the first report of a bifurcated stent-graft being placed through an 'end-to-side' anastomosed old aortobifemoral graft. Endovascular treatment of ruptured para-anastomotic aortic aneurysms can be accomplished successfully, avoiding open surgery which is associated with increased mortality and morbidity.

  2. Measurement of the formaldehyde ortho to para ratio in three molecular clouds

    NASA Technical Reports Server (NTRS)

    Kahane, C.; Lucas, R.; Frerking, M. A.; Langer, W. D.; Encrenaz, P.

    1984-01-01

    Observations of ortho and para H2CO in two types of clouds, a warm cloud (Orion A) and two cold clouds (L183 and TMC1), are presented. The ortho to para ratio in Orion deduced from the H2(C-13)O data is about three, while that for TMC1 is about one and that for L183 is 1-2. The former value is in agreement with the value calculated from chemical models of ortho and para H2CO production. The values for the cold clouds are consistent with thermal equilibrium at a temperature slightly smaller than 10 K.

  3. Management of large para-esophageal hiatal hernias.

    PubMed

    Collet, D; Luc, G; Chiche, L

    2013-12-01

    Para-esophageal hernias are relatively rare and typically occur in elderly patients. The various presenting symptoms are non-specific and often occur in combination. These include symptoms of gastro-esophageal reflux (GERD) in 26 to 70% of cases, microcytic anemia in 17 to 47%, and respiratory symptoms in 9 to 59%. Respiratory symptoms are not completely resolved by surgical intervention. Acute complications such as gastric volvulus with incarceration or strangulation are rare (estimated incidence of 1.2% per patient per year) but gastric ischemia leading to perforation is the main cause of mortality. Only patients with symptomatic hernias should undergo surgery. Prophylactic repair to prevent acute incarceration should only be undertaken in patients younger than 75 in good condition; surgical indications must be discussed individually beyond this age. The laparoscopic approach is now generally accepted. Resection of the hernia sac is associated with a lower incidence of recurrence. Repair of the hiatus can be reinforced with prosthetic material (either synthetic or biologic), but the benefit of prosthetic repair has not been clearly shown. Results of prosthetic reinforcement vary in different studies; it has been variably associated with four times fewer recurrences or with no measurable difference. A Collis type gastroplasty may be useful to lengthen a foreshortened esophagus, but no objective criteria have been defined to support this approach. The anatomic recurrence rate can be as high as 60% at 12years. But most recurrences are asymptomatic and do not affect the quality of life index. It therefore seems more appropriate to evaluate functional results and quality of life measures rather than to gauge success by a strict evaluation of anatomic hernia reduction. PMID:24060742

  4. Successful Mnemonics for "por"/"para" and Affirmative Commands with Pronouns.

    ERIC Educational Resources Information Center

    Mason, Keith

    1992-01-01

    Two mnemonic devices, "4A Rule" and "PERFECT," are described to simplify the learning of two grammar points: the placement of object pronouns with respect to commands and the distinction between "por" and "para." (five references) (LB)

  5. Tumores carcinoides gastrointestinales—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del tumor carcinoide gastrointestinal, así como referencias a estudios clínicos y otros temas relacionados.

  6. Carcinoma de tumor primario desconocido—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del carcinoma de tumor primario desconocido, así como referencias a estudios clínicos y otros temas relacionados.

  7. Efficient ortho-para conversion of H2 on interstellar grain surfaces

    NASA Astrophysics Data System (ADS)

    Bron, Emeric; Le Petit, Franck; Le Bourlot, Jacques

    2016-04-01

    Context. Fast surface conversion between ortho- and para-H2 has been observed in laboratory studies, and it has been proposed that this mechanism plays a role in the control of the ortho-para ratio in the interstellar medium. Observations of rotational lines of H2 in photo-dissociation regions (PDRs) have indeed found significantly lower ortho-para ratios than expected at equilibrium. The mechanisms controlling the balance of the ortho-para ratio in the interstellar medium thus remain incompletely understood, while this ratio can affect the thermodynamical properties of the gas (equation of state, cooling function). Aims: We aim to build an accurate model of ortho-para conversion on dust surfaces based on the most recent experimental and theoretical results, and to validate it by comparison to observations of H2 rotational lines in PDRs. Methods: We propose a statistical model of ortho-para conversion on dust grains with fluctuating dust temperatures. It is based on a master equation approach. This computation is then coupled to full PDR models and compared to PDR observations. Results: We show that the observations of rotational H2 lines indicate a high conversion efficiency on dust grains and that this high efficiency can be accounted for if taking dust temperature fluctuations into account with our statistical model of surface conversion. Simpler models that neglect the dust temperature fluctuations do not reach the high efficiency deduced from the observations. Moreover, this high efficiency induced by dust temperature fluctuations is very insensitive to the values of the model's microphysical parameters. Conclusions: Ortho-para conversion on grains is thus an efficient mechanism in most astrophysical conditions and can play a significant role in controlling the ortho-para ratio.

  8. A comparison of extraperitoneal versus transperitoneal laparoscopic para-aortic lymphadenectomy for staging of endometrial carcinoma

    PubMed Central

    Pakish, Janelle; Soliman, Pamela T.; Frumovitz, Michael; Westin, Shannon N.; Schmeler, Kathleen M.; dos Reis, Ricardo; Munsell, Mark F.; Ramirez, Pedro T.

    2014-01-01

    Objective The objective of our study was to compare the surgical outcomes of extraperitoneal laparoscopic, transperitoneal laparoscopic, and robotic transperitoneal para-aortic lymphadenectomy in endometrial cancer staging. Methods A retrospective review was performed from January 2007 to November 2012. Three groups were compared: extraperitoneal laparoscopic para-aortic lymphadenectomy and robotic hysterectomy and pelvic lymphadenectomy (“extraperitoneal group”; N=34); laparoscopic hysterectomy and transperitoneal pelvic and para-aortic lymphadenectomy (“transperitoneal laparoscopic group”; N=108); and robotic hysterectomy and transperitoneal pelvic and para-aortic lymphadenectomy (“transperitoneal robotic group”; N=52). Fisher’s exact test and Kruskal-Wallis test were used for statistical analysis, and statistical significance was defined as P< 0.05. Results Median number of para-aortic lymph nodes obtained was higher in the extraperitoneal group than in the transperitoneal laparoscopic and robotic groups (10, 5, and 4.5 nodes, respectively; P<0.001). Among patients with BMI <35 kg/m2, the median number of para-aortic nodes harvested was higher in the extraperitoneal group than in the transperitoneal laparoscopic and robotic groups (9, 4, and 5 nodes, respectively; P<0.01). The same pattern was observed among patients with BMI ≥35 kg/m2 (10, 6, and 3 nodes, respectively) (P=0.001). There was no significant difference in median estimated blood loss between the extraperitoneal group and either the transperitoneal laparoscopic group (100 vs. 112.5 mL; P=0.06) or the transperitoneal robotic group (100 vs. 67.5 mL; P=0.23). Conclusion Extraperitoneal laparoscopic para-aortic lymphadenectomy resulted in a higher number of para-aortic lymph nodes removed than transperitoneal laparoscopic or robotic lymphadenectomy. The extraperitoneal approach should be considered for endometrial cancer staging. PMID:24361579

  9. Ortho-Para Mixing Interaction in the Vinyl Radical Detected by Millimeter-Wave Spectroscopy and Prediction of Fast Ortho-Para Conversion Rate

    NASA Astrophysics Data System (ADS)

    Tanaka, Keiichi; Hayashi, Masato; Ohtsuki, Mitsuhiko; Harada, Kensuke; Tanaka, Takehiko

    2010-06-01

    Ortho-para mixing interaction due to the coupling of nuclear and electron spins was detected for the first time by millimeter-wave spectroscopy of deuterated vinyl radicals, H_2CCD and D_2CCD, of which the ground states are split by the tunneling motion of the α deuteron into two components 0^+ and 0^-, whose separations have been determined to be Δ E_0 = 1186.644(16) and 771.978(18) MHz, respectively. The observed tunneling-rotation spectra are significantly perturbed by the othro-para mixing interaction expressed by < 0^± |H'|0^mprangle = (δ aF(β)/2) S \\cdot(I_β 1-I_β 2), where I_β 1 and I_β 2 are spins of the two hydrogen nuclei in the β position and S is the electron spin, which connects rotational levels in the 0^+ and 0^- states, one being an ortho level and the other a para level. The δ aF(β) constants for H_2CCD and D_2CCD have been determined to be 68.06(53) and 10.63(94) MHz, respectively, consistent each other within the isotopic mass relation. The othro and para states are mixed by about 0.097% and 0.0123% due to this interaction. The δ aF constant for H_2CCH should be similar to that for H_2CCD because of the same probability density of the unpaired electron at the β protons, but could not be determined independently in our previous study. It is because the mixing of para- and ortho-levels of about 0.00044% is much smaller than that for H_2CCD due to the large tunneling splitting of Δ E_0=16271.8429(59) MHz. The rate constant of para to ortho (I_β = 0 → 1) conversion is predicted as 1.2× 10^5 s-1 torr-1 for H_2CCD, suggesting extremely rapid mutual conversion between ortho and para nuclear spin isomers of H_2CCD, which is more than 106 times faster compared with that in closed shell molecules such as H_2CO and H_2CCH_2. K. Tanaka, M. Hayashi, M. Ohtsuki, K. Harada, T. Tanaka, J. Chem. Phys., 131, 111101 (2009). K. Tanaka, M. Toshimitsu, K. Harada, T. Tanaka, J. Chem. Phys., 120, 3604 (2004).

  10. para-Sulphonato-calix[n]arenes as selective activators for the passage of molecules across the Caco-2 model intestinal membrane.

    PubMed

    Roka, Eszter; Vecsernyes, Miklos; Bacskay, Ildiko; Félix, Caroline; Rhimi, Moez; Coleman, Anthony W; Perret, Florent

    2015-06-01

    The passage of Lucifer Yellow across the Caco-2 intestinal model membrane has been studied for the para-sulphonato-calix[n]arenes, the results show that para-sulphonato-calix[4]arene and para-sulphonato-calix[8]arene activate membrane passage when used simultaneously with a transport probe, Lucifer Yellow, whereas para-sulphonato-calix[6]arene has no effect. PMID:25958962

  11. Amplificadores en bandas para receptores de uso radioastronómicos

    NASA Astrophysics Data System (ADS)

    Bava, A. J.; Sanz, A. J.

    Está en curso de realización en el IAR un cabezal de receptor, en la frecuencia de 3.3 GHz. Este receptor, conjuntamente con los sistemas de procesamientos actuales del IAR y con los futuros proyectos de procesamientos, permitirán las observaciones de las líneas de la molécula de CH, de gran interés astrofísico, y las observaciones en el continuo que complementarán las realizadas en 1420 MHz. En este trabajo, se presentan el diseño de los amplificadores de bajo ruido, que van a conformar las primeras etapas del receptor de 3.3 GHz. El desarrollo de los mismos se realizó teniendo en cuenta que la temperatura del sistema, según consideraciones observacionales, deberá ser de 60oK. Por tal motivo se realizó un diseño de bajo ruido utilizando como elemento activo un HEMT. Tanto los métodos de diseño, como el circuito final, fueron realizados y comprobados con programas de simulación, permitiendo de esta forma obtener el amplificador deseado.

  12. Revista de Investigacion Educativa, 2001 (Journal of Educational Research, 2001).

    ERIC Educational Resources Information Center

    Revista de Investigacion Educativa, 2001

    2001-01-01

    Articles in this volume focus on the following: student counseling and other factors determining course choices of university students; a focus on unspecific diagnoses of students with learning disabilities; self-evaluations aimed at improving the quality of schools; relationship of academic goals and the use of different learning and study…

  13. Revista de Investigacion Educativa, 2000 (Journal of Educational Research, 2000).

    ERIC Educational Resources Information Center

    Revista de Investigacion Educativa, 2000

    2000-01-01

    Articles in this volume focus on the following: teacher evaluation and quality management in education; steps toward a comprehensive and systematic staff evaluation; opinions of university students on teaching methods at science faculties; design of a scale to assess the ability to jump for the use in elementary school physical education; effects…

  14. Revista de Investigacion Educativa (Journal of Educational Research).

    ERIC Educational Resources Information Center

    Revista de Investigacion Educativa, 1997

    1997-01-01

    The two issues of this journal include the following articles (Titles are translated into English): "General Panorama of Research on Intercultural Education in Europe" (Margarita Bartolome Pina); "Incidence of Some Educational, Social, and Affective Factors in Alcohol Consumption by Teenagers" (Elvira Repetto Talavera, Ma. Peregrina Senra Varela);…

  15. Revista de Investigacion Educativa, 2002 (Journal of Educational Research, 2002).

    ERIC Educational Resources Information Center

    Revista de Investigacion Educativa, 2002

    2002-01-01

    This journal, which deals with topics in educational research, includes articles written in Spanish (translated here) such as the following: "Management of the Competence of Professional Action (CAP)]" (Benito Echeverria Samanes); "Concepts and Beliefs of Andalusian Secondary School Teachers on Mathematics Assessments" (Francisco Gil Cuadra, Luis…

  16. Revista de Investigacion Educativa, 1999 (Journal of Educational Research, 1999).

    ERIC Educational Resources Information Center

    Revista de Investigacion Educativa, 1999

    1999-01-01

    Articles in this volume, written in Spanish, focus on the following: intellectual style and academic performance; an explanatory integrated model of academic goals, learning strategies, and academic performance; a comparative situational study of drug addiction; early childhood depression and academic performance: a comparative study of patients…

  17. Revista de Investigacion Educativa, 1998 (Journal of Educational Research, 1998).

    ERIC Educational Resources Information Center

    Revista de Investigacion Educativa, 1998

    1998-01-01

    Articles in this volume focus on the following: specialized research; methodological challenges; establishment of a categorization system for sociometric analysis and its application in the multicultural classroom; a case study of factors to prevent school failure in children at risk; the KeyMatch-R scale (study of a curriculum-related diagnostic…

  18. Informacion Bibliografica Educativa (Bibliographic Educational Information). No. 12.

    ERIC Educational Resources Information Center

    Ministerio de Educacion Nacional, Bogota (Colombia). Centro Nacional de Documentacion e Informacion Pedagogica.

    The document contains six papers in Spanish which focus on the developmental and other aspects of education permanente. The first paper, The Concept of Education Permanente, discusses the concept as a new dimension in the area of education, capable of limiting inequalities in the presentation of education in general. Descriptions of 20…

  19. Boletin de Informacion Educativa, 12 (Educational Information Bulletin, 12).

    ERIC Educational Resources Information Center

    Ministerio de Educacion y Cultura, Santa Fe (Argentina). Centro de Documentacion e Informacion Educativa de la Provincia de Santa Fe.

    This bulletin, published in the Argentine province of Santa Fe, is the first in a series intended to report to teachers on all levels on educational reform, the important measures and approved proposals, and the ideas behind them. This issue contains policy speeches by several education officials in positions to effect educational improvement and…

  20. Informacion Bibliografica Educativa, N. 1 (Educational Bibliographic Information, N. 1).

    ERIC Educational Resources Information Center

    Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.

    This document discusses some considerations in the development of a system for educational documentation and information in Colombia. There is a need for a national policy of educational documentation to insure cooperation among various institutions involved in the task. The three main objectives are documentation and information for teacher…

  1. Boletin de Informacion Educativa, 13 (Educational Information Bulletin, 13).

    ERIC Educational Resources Information Center

    Ministerio de Educacion y Cultura, Santa Fe (Argentina). Centro de Documentacion e Informacion Educativa de la Provincia de Santa Fe.

    This bulletin on educational reform published in the Argentine province of Santa Fe begins with a speech by the provincial Minister of Education and Culture concerning educational development and reform. The second speech in the bulletin, also by the Education Minister, considers the role of the teacher. In conclusion, the bulletin contains the…

  2. Boletin de Informacion Educativa, 14 (Educational Information Bulletin, 14).

    ERIC Educational Resources Information Center

    Ministerio de Educacion y Cultura, Santa Fe (Argentina). Centro de Documentacion e Informacion Educativa de la Provincia de Santa Fe.

    This bulletin on educational reform published in the Argentine province of Santa Fe contains the committee reports written for the National Commission for Analysis and Evaluation of the Educational System in conjunction with the National Education Program established during the May 1970 meeting of Ministers of Education. The reports consider…

  3. Vesicular erythema multiforme-like reaction to para-phenylenediamine in a henna tattoo.

    PubMed

    Sidwell, Rachel U; Francis, Nick D; Basarab, Tamara; Morar, Nilesh

    2008-01-01

    Allergic contact dermatitis reaction to topical "black henna" tattoo is usually described secondary to the organic dye para-phenylenediamine, a derivative of analine. Allergic contact dermatitis reactions to para-phenylenediamine are well recognized and most commonly involve an eczematous reaction that may become generalized and an acute angio-edema. Only four previous instances have been reported of an erythema multiforme-like reaction to para-phenylenediamine and its derivatives, including only one mild reaction to a tattoo. A vesicular erythema multiforme-like reaction has not been reported. An erythema multiforme-like reaction to contact allergens is usually caused by potent allergens including plant quinolones in Compositae and sesquiterpene lactones in exotic woods, and it is also reported to topical drugs, epoxy resin, metals (particularly nickel), and various chemicals. A generalized vesicular erythema multiforme-like reaction is unusual, and rarely reported. We describe a 6-year-old boy who developed a localized, eczematous and severe generalized vesicular erythema multiforme-like contact allergy to para-phenylenediamine secondary to a henna tattoo. As henna tattoos are becoming increasingly popular, one should be aware of the possibility of such a reaction. This presentation also highlights the call to ban the use of para-phenylenediamine and its derivatives in dyes. PMID:18429780

  4. Sistemas Correctores de Campo Para EL Telescopio Ritchey-Chretien UNAM212

    NASA Astrophysics Data System (ADS)

    Cobos, F. J.; Galan, M. J.

    1987-05-01

    El telescopio UNAM2l2 fue inaugurado hace siete años y concebido para trabajar en las razones focales: f/7.5, F/13.5, F/27 y F/98. El diseño Ritchey-Chretién corresponde a la razón focal F/7.5 y el foco primario (F/2.286) no se consideró como utilizable para fotografía directa. En el Instituto de Astronomía de la UNAM, se diseñó y construyó un sistema corrector de campo para la razón focal F/7.5, que actualmente está en funcionamiento. Dentro de un programa de colaboración en diseflo y evaluación de sistemas ópticos, entre el Instituto de Astrofísica de Canarias y el Instituto de Astronomía de la UNAM, decidimos intentar el diseño de una correctora de campo para el foco primario del tȩlescopio UNAM212 bajo la consideración de que no son insalvables los problemas que implicaría su instalación y de que es muy posible que, en un futuro relativamente cercano, podamom tener un detector bidimenmional tipo Mepsicrón cuya área sensible haga tentadora la idea de construir la cámara directa para foco primario

  5. On the Ortho:Para Ratio of H+ 3 in Diffuse Molecular Clouds

    NASA Astrophysics Data System (ADS)

    Crabtree, Kyle N.; Indriolo, Nick; Kreckel, Holger; Tom, Brian A.; McCall, Benjamin J.

    2011-03-01

    The excitation temperature T 01 derived from the relative intensities of the J = 0 (para) and J = 1 (ortho) rotational levels of H2 has been assumed to be an accurate measure of the kinetic temperature in interstellar environments. In diffuse molecular clouds, the average value of T 01 is ~70 K. However, the excitation temperature T(H+ 3) derived from the (J, K) = (1, 1) (para) and (1, 0) (ortho) rotational levels of H+ 3 has been observed to be ~30 K in the same types of environments. In this work, we present observations of H+ 3 in three additional diffuse cloud sight lines for which H2 measurements are available, showing that in four of five cases T 01 and T(H+ 3) are discrepant. We then examine the thermalization mechanisms for the ortho:para ratios of H+ 3 and H2, concluding that indeed T 01 is an accurate measure of the cloud kinetic temperature, while the ortho:para ratio of H+ 3 need not be thermal. By constructing a steady-state chemical model taking into account the nuclear spin dependence of reactions involving H+ 3, we show that the ortho:para ratio of H+ 3 in diffuse molecular clouds is likely governed by a competition between dissociative recombination with electrons and thermalization via reactive collisions with H2. Based in part on observations made with ESO Telescopes at the La Silla or Paranal Observatories under program ID 384.C-0618.

  6. The formaldehyde ortho/para ratio as a probe of dark cloud chemistry and evolution

    NASA Technical Reports Server (NTRS)

    Dickens, J. E.; Irvine, W. M.

    1999-01-01

    We present measurements of the H2CO ortho/para ratio toward four star-forming cores, L723, L1228, L1527, and L43, and one quiescent core, L1498. Combining these data with earlier results by Minh et al., three quiescent cores are found to have ortho/para ratios near 3, the ratio of statistical weights expected for gas-phase formation processes. In contrast, ortho/para ratios are 1.5-2.1 in five star-forming cores, suggesting thermalization at a kinetic temperature of 10 K. We attribute modification of the ortho/para ratio in the latter cores to formation and/or equilibration of H2CO on grains with sub-sequent release back into the gas phase due to the increased energy inputs from the forming star and outflow. We see accompanying enhancements in the H2CO abundance relative to H, to support this idea. The results suggest that the formaldehyde ortho/para ratio can differentiate between quiescent cores and those in which low-mass star formation has occurred.

  7. Terahertz absorption spectrum of para and ortho water vapors at different humidities at room temperature

    NASA Astrophysics Data System (ADS)

    Xin, X.; Altan, H.; Saint, A.; Matten, D.; Alfano, R. R.

    2006-11-01

    Terahertz time-domain spectroscopy has been used to measure the absorption of water vapor in 0.2-2.4THz range from low to high humidity at room temperature. The observed absorption lines are due to the water molecular rotations in the ground vibrational state. We find that the absorption strength of para transitions increases as humidity increases, while the absorption strength of ortho transitions increases and then decreases in intensity with increasing humidity. We explain this difference based on the nuclear spin statistics based ratio of ortho to para water monomer populations at room temperature. The preferential adsorption on the solid surfaces of para water leads to an ortho dominated vapor cloud whose monomer rotational absorption intensity decreases due to the effects of dimerization, molecular collisions, clustering, and interactions with liquid droplets at high concentrations.

  8. Production and characterization of para-hydrogen gas for matrix isolation infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Sundararajan, K.; Sankaran, K.; Ramanathan, N.; Gopi, R.

    2016-08-01

    Normal hydrogen (n-H2) has 3:1 ortho/para ratio and the production of enriched para-hydrogen (p-H2) from normal hydrogen is useful for many applications including matrix isolation experiments. In this paper, we describe the design, development and fabrication of the ortho-para converter that is capable of producing enriched p-H2. The p-H2 thus produced was probed using infrared and Raman techniques. Using infrared measurement, the thickness and the purity of the p-H2 matrix were determined. The purity of p-H2 was determined to be >99%. Matrix isolation infrared spectra of trimethylphosphate (TMP) and acetylene (C2H2) were studied in p-H2 and n-H2 matrices and the results were compared with the conventional inert matrices.

  9. Electrical detection of ortho-para conversion in fullerene-encapsulated water

    NASA Astrophysics Data System (ADS)

    Meier, Benno; Mamone, Salvatore; Concistrè, Maria; Alonso-Valdesueiro, Javier; Krachmalnicoff, Andrea; Whitby, Richard J.; Levitt, Malcolm H.

    2015-08-01

    Water exists in two spin isomers, ortho and para, that have different nuclear spin states. In bulk water, rapid proton exchange and hindered molecular rotation obscure the direct observation of two spin isomers. The supramolecular endofullerene H2O@C60 provides freely rotating, isolated water molecules even at cryogenic temperatures. Here we show that the bulk dielectric constant of this substance depends on the ortho/para ratio, and changes slowly in time after a sudden temperature jump, due to nuclear spin conversion. The attribution of the effect to ortho-para conversion is validated by comparison with nuclear magnetic resonance and quantum theory. The change in dielectric constant is consistent with an electric dipole moment of 0.51+/-0.05 Debye for an encapsulated water molecule, indicating the partial shielding of the water dipole by the encapsulating cage. The dependence of bulk dielectric constant on nuclear spin isomer composition appears to be a previously unreported physical phenomenon.

  10. Quantitative structure–activity relationship analysis of the pharmacology of para-substituted methcathinone analogues

    PubMed Central

    Bonano, J S; Banks, M L; Kolanos, R; Sakloth, F; Barnier, M L; Glennon, R A; Cozzi, N V; Partilla, J S; Baumann, M H; Negus, S S

    2015-01-01

    Background and Purpose Methcathinone (MCAT) is a potent monoamine releaser and parent compound to emerging drugs of abuse including mephedrone (4-CH3 MCAT), the para-methyl analogue of MCAT. This study examined quantitative structure–activity relationships (QSAR) for MCAT and six para-substituted MCAT analogues on (a) in vitro potency to promote monoamine release via dopamine and serotonin transporters (DAT and SERT, respectively), and (b) in vivo modulation of intracranial self-stimulation (ICSS), a behavioural procedure used to evaluate abuse potential. Neurochemical and behavioural effects were correlated with steric (Es), electronic (σp) and lipophilic (πp) parameters of the para substituents. Experimental Approach For neurochemical studies, drug effects on monoamine release through DAT and SERT were evaluated in rat brain synaptosomes. For behavioural studies, drug effects were tested in male Sprague-Dawley rats implanted with electrodes targeting the medial forebrain bundle and trained to lever-press for electrical brain stimulation. Key Results MCAT and all six para-substituted analogues increased monoamine release via DAT and SERT and dose- and time-dependently modulated ICSS. In vitro selectivity for DAT versus SERT correlated with in vivo efficacy to produce abuse-related ICSS facilitation. In addition, the Es values of the para substituents correlated with both selectivity for DAT versus SERT and magnitude of ICSS facilitation. Conclusions and Implications Selectivity for DAT versus SERT in vitro is a key determinant of abuse-related ICSS facilitation by these MCAT analogues, and steric aspects of the para substituent of the MCAT scaffold (indicated by Es) are key determinants of this selectivity. PMID:25438806

  11. Simulation Studies of the Vibrational Dynamics of para-HYDROGEN Clusters

    NASA Astrophysics Data System (ADS)

    Faruk, Nabil F.; Yang, Jing; Le Roy, Robert J.; Roy, Pierre-Nicholas

    2011-06-01

    This paper discusses the construction and application of reduced-dimensional potential energy surfaces for use in performing simulation of para-hydrogen clusters. Simple spherical averaging and `adiabatic-hindered-rotor' averaging treatments of the angular degrees of freedom are considered and compared. The resulting one-dimensional surface is used in quantum Monte Carlo simulations of para-hydrogen clusters of varying sizes. Energetic, and structural properties are computed and compared to previously published results, and vibrational frequency shifts are predicted and compared to available experimental measurements. H. Li, P.N. Roy and R.J. Le Roy, J. Chem. Phys. 133, 104305 (2010).

  12. Le lipome para testiculaire: à propos d'un cas rare

    PubMed Central

    Lasri, Abdelouahed; Lamchahab, Hamza; Lahyani, Mounir; Karmouni, Tarik; Elkhader, Khalid; Koutani, Abdellatif; Andaloussi, Ahmed Ibn Attya

    2015-01-01

    Les tumeurs para testiculaires sont des tumeurs rares et complexes qui ont une symptomatologie insidieuse et pauvre. Les formes bénignes représentent 70%. Le lipome para testiculaire étant le type le plus fréquent. L'examen clinique est peu spécifique. L'examen échographique est la pierre angulaire pour assoir le diagnostic. Le traitement chirurgical s'impose en cas de tumeur symptomatique, l'histologie étant habituellement typique permet la confirmation diagnostique. Le pronostic est bon malgré d’éventuelles récidives. PMID:26175802

  13. Experiments at Scale with In-Situ Visualization Using ParaView/Catalyst in RAGE

    SciTech Connect

    Kares, Robert John

    2014-10-31

    In this paper I describe some numerical experiments performed using the ParaView/Catalyst in-situ visualization infrastructure deployed in the Los Alamos RAGE radiation-hydrodynamics code to produce images from a running large scale 3D ICF simulation on the Cielo supercomputer at Los Alamos. The detailed procedures for the creation of the visualizations using ParaView/Catalyst are discussed and several images sequences from the ICF simulation problem produced with the in-situ method are presented. My impressions and conclusions concerning the use of the in-situ visualization method in RAGE are discussed.

  14. Quantum rotation of ortho and para-water encapsulated in a fullerene cage

    PubMed Central

    Beduz, Carlo; Carravetta, Marina; Chen, Judy Y.-C.; Concistrè, Maria; Denning, Mark; Frunzi, Michael; Horsewill, Anthony J.; Johannessen, Ole G.; Lawler, Ronald; Lei, Xuegong; Levitt, Malcolm H.; Li, Yongjun; Mamone, Salvatore; Murata, Yasujiro; Nagel, Urmas; Nishida, Tomoko; Ollivier, Jacques; Rols, Stéphane; Rõõm, Toomas; Sarkar, Riddhiman; Turro, Nicholas J.; Yang, Yifeng

    2012-01-01

    Inelastic neutron scattering, far-infrared spectroscopy, and cryogenic nuclear magnetic resonance are used to investigate the quantized rotation and ortho–para conversion of single water molecules trapped inside closed fullerene cages. The existence of metastable ortho-water molecules is demonstrated, and the interconversion of ortho-and para-water spin isomers is tracked in real time. Our investigation reveals that the ground state of encapsulated ortho water has a lifted degeneracy, associated with symmetry-breaking of the water environment. PMID:22837402

  15. [PDS cord fixation of sternoclavicular dislocation and para-articular clavicular fractures].

    PubMed

    Friedl, W; Fritz, T

    1994-05-01

    Sternoclavicular joint dislocation and para-articular fractures of the clavicle are rare injuries. Because severe complications of dorsal dislocations have often been seen and because functional impairment has often followed ventral dislocations, we treat most patients with such injuries operatively. Internal fixation with K-wires frequently leads to severe complications. We present our operation techniques with a resorbable 2 mm polydioxanon cord. This pack up technique can be used in both dislocations and para-articular fractures with no risk of implant dislocation. PMID:8052863

  16. In para totale...una cosa da panico...sulla lingua dei giovani in Italia (In para totale...una cosa da panico...The Language of Young People in Italy).

    ERIC Educational Resources Information Center

    Marcato, Carla

    1997-01-01

    Describes and analyzes the language of young people in Italy today. Particular focus is on the expressions using "para" (e.g., "in para totale" = to be very bored or worried) and the phrase "una cosa da panico" (something terrible or its opposite something wonderful). (CFM)

  17. EVALUATION OF PARA-DICHLOROBENZENE EMISSIONS FROM SOLID MOTH REPELLANT AS A SOURCE OF INDOOR AIR POLLUTION

    EPA Science Inventory

    The paper reports results of dynamic and static chamber tests to evaluate para-dichlorobenzene emission rates from mothcakes. he data were analyzed by a model that assumes that the para-dichlorobenzene emission from mothcakes is a temperature-sensitive sublimation process. ull-sc...

  18. EVALUATION OF PARA-DICHLOROBENZENE EMISSIONS FROM SOLID MOTH REPELLANT AS A SOURCE OF INDOOR AIR POLLUTION

    EPA Science Inventory

    Mothcakes made of para-dichlorobenzene have been widely available for the general population to be used as a moth repellant to protect garments from insect damage. Usually, a mothcake is expected to last for weeks or even months during which the para-dichlorobenzene emits slowly ...

  19. Fabrication of multipotent poly-para-xylylene particles in controlled nanoscopic dimensions.

    PubMed

    Yuan, Ruei-Hung; Li, Yi-Jye; Sun, Ho-Yi; Wu, Chih-Yu; Guan, Zhen-Yu; Ho, Hsin-Ying; Fang, Cheng-Yuan; Chen, Hsien-Yeh

    2016-03-01

    In this study, poly-para-xylylene-based multifunctional nanoparticles (PPX-NPs) were fabricated. Based on the solubility characteristics determined for asymmetrically substituted poly-para-xylylenes in polar solvents, well-dispersed nanocolloids with a controllable size ranging from 50 to 800nm were produced in solution by the displacement of the solvent (water). These size ranges were found to have acceptable cellular compatibility through examinations of cultured 3T3 fibroblasts and adipose-derived stem cells treated with the PPX-NPs. In addition, these nanoscale PPX-NPs exhibited versatile bioconjugation properties in that a variety of available functional groups can be adopted from their counterpart, thin-film poly-para-xylylenes, during the production of these nanoparticles. For instance, bifunctional PPX-NPs with maleimide and benzoyl moieties were produced to enable immobilization via a maleimide-thiol reaction concurrent with a photochemical reaction. A cleavable PPX-NP was also produced with a thiol-exchangeable surface property. Additionally, by performing electrohydrodynamic jetting of parallel polymer solutions of selected poly-para-xylylenes, Janus-type or multicompartment PPX-NPs were created. The PPX-NPs can potentially be used for various biomedical applications such as combined diagnostics and drug delivery, multiplexing of detection, multiple-drug loading, and the targeted delivery of biomolecules or drugs. PMID:26724467

  20. Energia Renovable para Centros de Salud Rurales (Renewable Energy for Rural Health Clinics)

    SciTech Connect

    Jimenez, T.; Olson, K.

    1999-07-28

    Esta es la primera de una serie de guias de aplicaciones que el Programa de Energia de Villas de NREL esta comisionando para acoplar sistemas comerciales renovables con aplicaciones rurales, incluyendo agua, escuelas rurales y micro empresas. La guia esta complementada por las actividades de desarrollo del Programa de Energia de Villas de NREL, proyectos pilotos internacionales y programas de visitas profesionales.

  1. Cannabis y canabinoides (PDQ®)—Versión para profesionales de salud

    Cancer.gov

    Resumen de información revisada por expertos sobre el uso del Cannabis y canabinoides para el tratamiento de los efectos secundarios relacionados con el tratamiento del cáncer, como la náusea y el vómito.

  2. Cannabis y canabinoides (PDQ®)—Versión para pacientes

    Cancer.gov

    Resumen de información revisada por expertos sobre el uso del Cannabis y canabinoides para el tratamiento de los efectos secundarios relacionados con el tratamiento del cáncer como la náusea y el vómito.

  3. Cáncer de intestino delgado—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de intestino delgado, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  4. Interrupting Commemoration: Thinking with Art, Thinking through the Strictures of Argentina's "Espacio para la memoria"

    ERIC Educational Resources Information Center

    Paolantonio, Mario Di

    2011-01-01

    Recently, a few buildings within the "Espacio para la memoria" in Buenos Aires have been designated as a UNESCO Centre where, amongst other educational activities, evidentiary materials of the past repression are to be stored and displayed. Another building in the complex houses a Community Centre operated by the Mothers of the Plaza de Mayo,…

  5. Cáncer colorrectal—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento, la prevención, las causas y los exámenes de detección del cáncer de colon y recto, así como referencias a estudios clínicos, estadísticas y otros temas.

  6. Autoguía para el telescopio 2,15 mts de CASLEO

    NASA Astrophysics Data System (ADS)

    Aballay, J. A.; Casagrande, A. R.; Pereyra, P. F.; Marún, A. H.

    Se está desarrollando un sistema de autoguía para el telescopio de 2,15 mts. El mismo se realizará aprovechando el Offset Guider. Al ocular móvil de éste se vinculará alguna cámara digital (ST4-ST7-CH250) para lograr la visión del objeto. El funcionamiento del equipo será el siguiente: primero, dadas las coordenadas del objeto a observar, se tomarán las coordenadas del telescopio para que, a través de una base de datos, se determine un campo de objetos que sirvan para la cámara de visión, luego, la PC obtendrá el offset entre la estrella de observación y la estrella seleccionada como guía, este valor será trasladado a los motores que posicionarán en forma automática el ocular. Una vez que la estrella es visualizada en la cámara (monitor de PC ) se correrá el programa que guiará el telescopio automáticamente.

  7. Experimental and theoretical investigation of para-aminophenol ionization in corona discharge

    NASA Astrophysics Data System (ADS)

    Bahrami, H.; Salehabadi, H.

    2015-03-01

    Ionization of para-aminophenol was investigated using an ion mobility spectrometer equipped with a corona discharge as ionization source. The experimental results were confirmed with the use of theoretical method, based on density functional theory. Two peaks were observed in the ion mobility spectrum in the positive ion mode which was corresponded to the protonated isomers of para-aminophenol. It was observed that the relative intensities of the peaks depend on the sample concentration and the nature of the reactant ions. The relative energies of ions derived from protonation of para-aminophenol and its topical proton affinities were determined for different sites in the gas phase. The peak with the lower drift time was assigned to the oxygen protonated isomer and the other peak was ascribed to the nitrogen protonated isomer of para-aminophenol. The calculated dipole moment and localized charge of each isomer were used to verify the ion mobility peak separation. It was shown that combination of theoretical and experimental tools leads to reliable prediction of reactive protonation sites of chemicals in a corona discharge.

  8. Synthesis and properties of para-substituted NCN-pincer palladium and platinum complexes.

    PubMed

    Slagt, Martijn Q; Rodríguez, Gema; Grutters, Michiel M P; Klein Gebbink, Robertus J M; Klopper, Wim; Jenneskens, Leonardus W; Lutz, Martin; Spek, Anthony L; van Koten, Gerard

    2004-03-19

    A variety of para-substituted NCN-pincer palladium(II) and platinum(II) complexes [MX(NCN-Z)] (M=Pd(II), Pt(II); X=Cl, Br, I; NCN-Z=[2,6-(CH(2)NMe(2))(2)C(6)H(2)-4-Z](-); Z=NO(2), COOH, SO(3)H, PO(OEt)(2), PO(OH)(OEt), PO(OH)(2), CH(2)OH, SMe, NH(2)) were synthesised by routes involving substitution reactions, either prior to or, notably, after metalation of the ligand. The solubility of the pincer complexes is dominated by the nature of the para substituent Z, which renders several complexes water-soluble. The influence of the para substituent on the electronic properties of the metal centre was studied by (195)Pt NMR spectroscopy and DFT calculations. Both the (195)Pt chemical shift and the calculated natural population charge on platinum correlate linearly with the sigma(p) Hammett substituent constants, and thus the electronic properties of predesigned pincer complexes can be predicted. The sigma(p) value for the para-PtI group itself was determined to be -1.18 in methanol and -0.72 in water/methanol (1/1). Complexes substituted with protic functional groups (CH(2)OH, COOH) exist as dimers in the solid state due to intermolecular hydrogen-bonding interactions. PMID:15034878

  9. Cáncer de páncreas—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de páncreas, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  10. Cáncer de vagina—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de vagina, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  11. An Analysis of Interlanguage Development Over Time: Part 1, "por" and "para".

    ERIC Educational Resources Information Center

    Guntermann, Gail

    1992-01-01

    The first part of a larger planned investigation, this study examines the use of "por" and "para" by nine Peace Corps volunteers in oral interviews at the end of training and roughly one year later, to trace their acquisition over time, in two learning contexts. (24 references) (LB)

  12. The Acquisition of Lexical Meaning in a Study Abroad Context: The Spanish Prepositions "por" and "para."

    ERIC Educational Resources Information Center

    Lafford, Barbara A.; Ryan, John M.

    1995-01-01

    Examination of the development of form/function relations of the prepositions "por" and "para" at different levels of proficiency in the interlanguage of study-abroad students in Granada, Spain, revealed "noncanonical" as well as "canonical" uses of these prepositions. The most common noncanonical uses were as substitutions for other prepositions…

  13. Preguntas para hacerle al doctor acerca del cáncer

    Cancer.gov

    Serie de preguntas, organizadas por tema, que los pacientes con cáncer pueden hacer al médico o a otros miembros de su equipo de atención médica para conocer más acerca de su tipo de cáncer y lo que pueden esperar.

  14. Terapia hormonal para la menopausia y el cáncer

    Cancer.gov

    Hoja informativa acerca de los resultados de los estudios sobre el uso de la terapia hormonal para la menopausia. Incluye información sobre el efecto de esta terapia en el cuerpo y explica los riesgos y beneficios del uso de hormonas.

  15. Resultados de estudio para cáncer de pulmón indica

    Cancer.gov

    El Instituto Nacional del Cáncer (NCI) da a conocer hoy resultados iniciales de un estudio de gran envergadura sobre métodos de detección para reducir el número de muertes por cáncer de pulmón al detectar cánceres en estadios relativamente iniciales.

  16. Factor Structure of the "Escala de Autoeficacia para la Depresion en Adolescentes" (EADA)

    ERIC Educational Resources Information Center

    Diaz-Santos, Mirella; Cumba-Aviles, Eduardo; Bernal, Guillermo; Rivera-Medina, Carmen

    2011-01-01

    The current concept and measures of self-efficacy for depression in adolescents do not consider developmental and cultural aspects essential to understand and assess this construct in Latino youth. We examined the factor structure of the "Escala de Autoeficacia para la Depresion en Adolescentes" (EADA), a Spanish instrument designed to assess this…

  17. Sarcoma de tejido blando—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del sarcoma de tejido blando, así como referencias a estudios clínicos, investigación, estadísticas y otros temas relacionados con este tipo de cáncer.

  18. Ortho-para conversion of endohedral water in the fullerene C60 at cryogenic temperatures

    NASA Astrophysics Data System (ADS)

    Shugai, Anna; Nagel, U.; Rõõm, T.; Mamone, S.; Concistrè, M.; Meier, B.; Krachmalnicoff, A.; Whitby, R. J.; Levitt, M. H.; Lei, Xuegong; Li, Yongjun; Turro, N. J.

    2015-03-01

    Water displays the phenomenon of spin isomerism in which the two proton spins either couple to form a triplet (ortho water, I = 1) or a singlet nuclear spin state (para water, I = 0). Here we study the interconversion of para and ortho water. The exact mechanism of this process is still not fully understood. In order to minimize interactions between molecules we use a sample where a single H2O is trapped in the C60 molecular cage (H2O@C60)andH2O@C60iscrystallized.H2O@C60 has long-lived ortho state and ortho-para conversion kinetics is non-exponential at LHeT. We studied mixtures of H2O@C60, D2O@C60 and C60 using IR absorption, NMR and dielectric measurements. We saw the speeding up of the interconversion with the growth of H2O@C60 concentration in C60 or when D2O@C60 was added. At some temperatures the kinetics is exponential. Models are discussed in order to explain the T and concentration dependence of ortho-para interconversion kinetics. This work was supported by institutional research funding IUT23-3 of the Estonian Ministry of Education and Research.

  19. Irradiation of para-aortic lymph node metastases from carcinoma of the cervix or endometrium

    SciTech Connect

    Komaki, R.; Mattingly, R.F.; Hoffman, R.G.; Barber, S.W.; Satre, R.; Greenberg, M.

    1983-04-01

    Twenty-two patients with biopsy-proved para-aortic lymph node metastases from carcinoma of the cervix (15 patients) or endometrium (7 patients) received a median dose of 5,000 rad/25 fractions. Para-aortic nodal metastases were controlled in 77% of cases. Control was significantly lower following radical retroperitoneal lymph node dissection than less extensive sampling procedures. Obstruction of the small bowel developed in 3 patients with tumor recurrence in the para-aortic region. Eight of the 10 patients who were disease-free at 2 years received >5,000 rad. Three patients were still alive without disease at 129, 63, and 60 months, respectively. The 5-year disease-free survival rate was 40% for cervical cancer and 60% for endometrial cancer: in the former group, it was significantly different depending on whether the para-aortic nodes were irradiated (40%) or not (0%). The authors suggest that 5,000-5,500 rad in 5-5.5 weeks is well tolerated and can control aortic nodal metastases in cervical and possibly endometrial cancer.

  20. Construction of erythrinane skeleton via Pd(0)-catalyzed intramolecular dearomatization of para-aminophenols.

    PubMed

    Xu, Ren-Qi; Gu, Qing; Wu, Wen-Ting; Zhao, Zhuo-An; You, Shu-Li

    2014-11-01

    A novel Pd(0)-catalyzed intramolecular arylative dearomatization of para-aminophenol derivatives is described. In the presence of 1.25 mol % [Pd(C3H5)Cl]2 and 3.75 mol % RuPhos, the arylative dearomatization reaction proceeds smoothly for a broad range of substrates, offering an efficient synthetic route to erythrinane derivatives in excellent yields. PMID:25308898

  1. Antimicrobial effect of para-alkoxyphenylcarbamic acid esters containing substituted N-phenylpiperazine moiety.

    PubMed

    Malík, Ivan; Bukovský, Marián; Andriamainty, Fils; Gališinová, Jana

    2013-01-01

    In current research, nine basic esters of para-alkoxyphenylcarbamic acid with incorporated 4-(4-fluoro-/3-trifluoromethylphenyl)piperazin-1-yl fragment, 6i-6m and 8f-8i, were screened for their in vitro antimicrobial activity against Candida albicans, Staphylococcus aureus and Escherichia coli, respectively. Taking into account the minimum inhibitory concentration assay (MIC), as the most active against given yeast was evaluated 8i (MIC = 0.20 mg/mL), the most lipophilic structure containing para-butoxy and trifluoromethyl substituents. Investigating the efficiency of the compounds bearing only a single atom of fluorine and appropriate para-alkoxy side chain against Candida albicans, the cut-off effect was observed. From evaluated homological series, the maximum of the effectiveness was noticed for the stucture 6 k (MIC = 0.39 mg/mL), containing para-propoxy group attached to phenylcarbamoyloxy fragment, beyond which the compounds ceased to be active. On the contrary, all the tested molecules were against Staphylococcus aureus and Escherichia coli (MICs > 1.00 mg/mL) practically inactive. PMID:24294237

  2. Up from Apathy: Para-Professional Training for the Socially Disadvantaged

    ERIC Educational Resources Information Center

    Jones, Mark J.; Wright, Bobbye S.

    1970-01-01

    Describes a program of training for young men to fill a para-professional position in the growing field of social services. The program provides training in human relations, basic skills, and on-the-job techniques. Training Technology is a quarterly supplement to Educational Technology Magazine. (GR)

  3. Can para-aryl-dithiols cross-link two plasmonic noble nanoparticles as monolayer dithiolate spacers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Para-aryl-dithiols (PADTs, HS-(C6H4)n-SH, n = 1, 2, and 3) have been used extensively in molecular electronics, surface-enhanced Raman spectroscopy (SERS), and quantum electron tunneling between two gold or silver nanoparticles (AuNPs and AgNPs). One popular belief is that these dithiols cross-link ...

  4. Cáncer de la corteza suprarrenal—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del carcinoma de corteza suprarrenal, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  5. Tumores de hipófisis—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del tumor de hipófisis, así como referencias a estudios clínicos, investigación y otros temas relacionados.

  6. Cáncer de útero—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento, la prevención, las causas y los exámenes de detección del cáncer uterino, así como referencias a estudios clínicos, investigación, estadísticas y otros temas.

  7. Tumores extracraneales de células germinativas—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del tumor extracraneal de células germinativas en los niños, así como referencias a estudios clínicos y otros temas relacionados.

  8. Antimicrobial effect of para-alkoxyphenylcarbamic acid esters containing substituted N-phenylpiperazine moiety

    PubMed Central

    Malík, Ivan; Bukovský, Marián; Andriamainty, Fils; Gališinová, Jana

    2013-01-01

    In current research, nine basic esters of para-alkoxyphenylcarbamic acid with incorporated 4-(4-fluoro-/3-trifluoromethylphenyl)piperazin-1-yl fragment, 6i–6m and 8f–8i, were screened for their in vitro antimicrobial activity against Candida albicans, Staphylococcus aureus and Escherichia coli, respectively. Taking into account the minimum inhibitory concentration assay (MIC), as the most active against given yeast was evaluated 8i (MIC = 0.20 mg/mL), the most lipophilic structure containing para-butoxy and trifluoromethyl substituents. Investigating the efficiency of the compounds bearing only a single atom of fluorine and appropriate para-alkoxy side chain against Candida albicans, the cut-off effect was observed. From evaluated homological series, the maximum of the effectiveness was noticed for the stucture 6 k (MIC = 0.39 mg/mL), containing para-propoxy group attached to phenylcarbamoyloxy fragment, beyond which the compounds ceased to be active. On the contrary, all the tested molecules were against Staphylococcus aureus and Escherichia coli (MICs > 1.00 mg/mL) practically inactive. PMID:24294237

  9. Delirio (PDQ®)—Versión para profesionales de salud

    Cancer.gov

    Resumen de información revisada por expertos acerca del delirio como una complicación a causa del cáncer o su tratamiento. Se discuten los enfoques de los cuidados médicos de apoyo, asi como farmacológicos para el manejo del delirio.

  10. Cáncer de hueso—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de hueso (óseo), así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  11. Estudios ALCHEMIST para el cáncer de pulmón en estadio inicial

    Cancer.gov

    ALCHEMIST comprende tres estudios clínicos integrados de medicina de precisión diseñados para identificar a personas con cáncer de pulmón en estadio inicial cuyos tumores tienen ciertos cambios genéticos poco comunes.

  12. Cáncer de ano—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de ano, así como referencias a estudios clínicos y otros temas relacionados con este tipo de cáncer.

  13. Cáncer de tiroides—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de tiroides, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  14. Cáncer de pene—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de pene, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  15. Cáncer de testículo—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento, las causas y los exámenes de detección del cáncer de testículo, así como referencias a estudios clínicos, investigación y otros temas.

  16. Cáncer de vejiga—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento, las causas y los exámenes de detección del cáncer de vejiga, así como referencias a estudios clínicos, investigación, estadísticas y otros temas.

  17. Cáncer de vulva—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de vulva, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  18. Cáncer de paratiroides—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de paratiroides, así como referencias a estudios clínicos, investigación y otros temas relacionados con este tipo de cáncer.

  19. Cáncer de uretra—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento del cáncer de uretra, así como referencias a estudios clínicos y otros temas relacionados con este tipo de cáncer.

  20. Fatiga (PDQ®)—Versión para profesionales de salud

    Cancer.gov

    Resumen de información revisada por expertos acerca de la fatiga, una afección caracterizada por extremo cansancio e incapacidad para funcionar por la falta de energía, que a menudo se observa como una complicación del cáncer y su tratamiento.

  1. Rotational excitation of HCN by para- and ortho-H{sub 2}

    SciTech Connect

    Vera, Mario Hernández; Kalugina, Yulia; Denis-Alpizar, Otoniel; Stoecklin, Thierry; Lique, François

    2014-06-14

    Rotational excitation of the hydrogen cyanide (HCN) molecule by collisions with para-H{sub 2}( j = 0, 2) and ortho-H{sub 2}( j = 1) is investigated at low temperatures using a quantum time independent approach. Both molecules are treated as rigid rotors. The scattering calculations are based on a highly correlated ab initio 4-dimensional (4D) potential energy surface recently published. Rotationally inelastic cross sections among the 13 first rotational levels of HCN were obtained using a pure quantum close coupling approach for total energies up to 1200 cm{sup −1}. The corresponding thermal rate coefficients were computed for temperatures ranging from 5 to 100 K. The HCN rate coefficients are strongly dependent on the rotational level of the H{sub 2} molecule. In particular, the rate coefficients for collisions with para-H{sub 2}( j = 0) are significantly lower than those for collisions with ortho-H{sub 2}( j = 1) and para-H{sub 2}( j = 2). Propensity rules in favor of even Δj transitions were found for HCN in collisions with para-H{sub 2}( j = 0) whereas propensity rules in favor of odd Δj transitions were found for HCN in collisions with H{sub 2}( j ⩾ 1). The new rate coefficients were compared with previously published HCN-para-H{sub 2}( j = 0) rate coefficients. Significant differences were found due the inclusion of the H{sub 2} rotational structure in the scattering calculations. These new rate coefficients will be crucial to improve the estimation of the HCN abundance in the interstellar medium.

  2. Hox and ParaHox gene expression in early body plan patterning of polyplacophoran mollusks.

    PubMed

    Fritsch, Martin; Wollesen, Tim; Wanninger, Andreas

    2016-03-01

    Molecular developmental studies of various bilaterians have shown that the identity of the anteroposterior body axis is controlled by Hox and ParaHox genes. Detailed Hox and ParaHox gene expression data are available for conchiferan mollusks, such as gastropods (snails and slugs) and cephalopods (squids and octopuses), whereas information on the putative conchiferan sister group, Aculifera, is still scarce (but see Fritsch et al., 2015 on Hox gene expression in the polyplacophoran Acanthochitona crinita). In contrast to gastropods and cephalopods, the Hox genes in polyplacophorans are expressed in an anteroposterior sequence similar to the condition in annelids and other bilaterians. Here, we present the expression patterns of the Hox genes Lox5, Lox4, and Lox2, together with the ParaHox gene caudal (Cdx) in the polyplacophoran A. crinita. To localize Hox and ParaHox gene transcription products, we also investigated the expression patterns of the genes FMRF and Elav, and the development of the nervous system. Similar to the other Hox genes, all three Acr-Lox genes are expressed in an anteroposterior sequence. Transcripts of Acr-Cdx are seemingly present in the forming hindgut at the posterior end. The expression patterns of both the central class Acr-Lox genes and the Acr-Cdx gene are strikingly similar to those in annelids and nemerteans. In Polyplacophora, the expression patterns of the Hox and ParaHox genes seem to be evolutionarily highly conserved, while in conchiferan mollusks these genes are co-opted into novel functions that might have led to evolutionary novelties, at least in gastropods and cephalopods. PMID:27098677

  3. Hox and ParaHox gene expression in early body plan patterning of polyplacophoran mollusks

    PubMed Central

    Fritsch, Martin; Wollesen, Tim

    2016-01-01

    ABSTRACT Molecular developmental studies of various bilaterians have shown that the identity of the anteroposterior body axis is controlled by Hox and ParaHox genes. Detailed Hox and ParaHox gene expression data are available for conchiferan mollusks, such as gastropods (snails and slugs) and cephalopods (squids and octopuses), whereas information on the putative conchiferan sister group, Aculifera, is still scarce (but see Fritsch et al., 2015 on Hox gene expression in the polyplacophoran Acanthochitona crinita). In contrast to gastropods and cephalopods, the Hox genes in polyplacophorans are expressed in an anteroposterior sequence similar to the condition in annelids and other bilaterians. Here, we present the expression patterns of the Hox genes Lox5, Lox4, and Lox2, together with the ParaHox gene caudal (Cdx) in the polyplacophoran A. crinita. To localize Hox and ParaHox gene transcription products, we also investigated the expression patterns of the genes FMRF and Elav, and the development of the nervous system. Similar to the other Hox genes, all three Acr‐Lox genes are expressed in an anteroposterior sequence. Transcripts of Acr‐Cdx are seemingly present in the forming hindgut at the posterior end. The expression patterns of both the central class Acr‐Lox genes and the Acr‐Cdx gene are strikingly similar to those in annelids and nemerteans. In Polyplacophora, the expression patterns of the Hox and ParaHox genes seem to be evolutionarily highly conserved, while in conchiferan mollusks these genes are co‐opted into novel functions that might have led to evolutionary novelties, at least in gastropods and cephalopods. PMID:27098677

  4. Ancient origins of axial patterning genes: Hox genes and ParaHox genes in the Cnidaria.

    PubMed

    Finnerty, J R; Martindale, M Q

    1999-01-01

    Among the bilaterally symmetrical, triploblastic animals (the Bilateria), a conserved set of developmental regulatory genes are known to function in patterning the anterior-posterior (AP) axis. This set includes the well-studied Hox cluster genes, and the recently described genes of the ParaHox cluster, which is believed to be the evolutionary sister of the Hox cluster (Brooke et al. 1998). The conserved role of these axial patterning genes in animals as diverse as frogs and flies is believed to reflect an underlying homology (i.e., all bilaterians derive from a common ancestor which possessed an AP axis and the developmental mechanisms responsible for patterning the axis). However, the origin and early evolution of Hox genes and ParaHox genes remain obscure. Repeated attempts have been made to reconstruct the early evolution of Hox genes by analyzing data from the triphoblastic animals, the Bilateria (Schubert et al. 1993; Zhang and Nei 1996). A more precise dating of Hox origins has been elusive due to a lack of sufficient information from outgroup taxa such as the phylum Cnidaria (corals, hydras, jellyfishes, and sea anemones). In combination with outgroup taxa, another potential source of information about Hox origins is outgroup genes (e.g., the genes of the ParaHox cluster). In this article, we present cDNA sequences of two Hox-like genes (anthox2 and anthox6) from the sea anemone, Nematostella vectensis. Phylogenetic analysis indicates that anthox2 (= Cnox2) is homologous to the GSX class of ParaHox genes, and anthox6 is homologous to the anterior class of Hox genes. Therefore, the origin of Hox genes and ParaHox genes occurred prior to the evolutionary split between the Cnidaria and the Bilateria and predated the evolution of the anterior-posterior axis of bilaterian animals. Our analysis also suggests that the central Hox class was invented in the bilaterian lineage, subsequent to their split from the Cnidaria. PMID:11324016

  5. Revista Interamericana de Educacion de Adultos, 2003 (Interamerican Review of Adult Education, 2003).

    ERIC Educational Resources Information Center

    Guerra, Alfonso Rangel, Ed.

    2003-01-01

    This journal offers a collection of Spanish-language articles, including: "Educacion a Distancia y Uso de las Tecnologias: Experiencias Desafios y Oportunidades Educativas para Jovenes y Adultos" (Ma. Mercedes Ruiz); "Volver a a Educacion Fundamental? Notas para una Arquelogia de los Mandatos Fundacionales del CREFAL" (Jorge Rivas Diaz); "Una…

  6. Saturn’s Tropospheric Temperatures and Para-Hydrogen Distribution from Ten Years of Cassini Observations

    NASA Astrophysics Data System (ADS)

    Fletcher, Leigh N.; Irwin, Patrick G.; Sinclair, James; Giles, Rohini; Barstow, Joanna; Achterberg, Richard K.; Orton, Glenn S.

    2014-11-01

    Cassini/CIRS observations of Saturn’s 10-1400 cm-1 spectrum have been inverted to construct a global record of tropospheric temperature and para-hydrogen variability over the ten-year span of the Cassini mission. The data record the slow reversal of seasonal asymmetries in tropospheric conditions from northern winter (2004, Ls=293), through northern spring equinox (2009, Ls=0) to the present day (2014, Ls=60). Mid-latitude tropospheric temperatures have cooled by approximately 4-6 K in the south and warmed by 2-4 K in the north, with the seasonal contrast decreasing with depth. CIRS detected the north polar minimum 100-mbar temperatures 6-8 years after winter solstice, whereas the south polar maximum occurred 1-2 years after summer solstice, consistent with the lag times predicted by radiative equilibrium models. Warm polar cyclones and the northern hexagon persist throughout the mission, suggesting that they are permanent features of Saturn’s tropospheric circulation. The 200-mbar thermal enhancement (“knee”) that was strongest in the summer but weak or absent in winter in 2004-2006 (Fletcher et al., 2007, Icarus 189, p.457-478) has now shifted northward and is present globally in 2014, suggestive of radiative heating in Saturn’s tropospheric haze layer. Saturn’s para-H2 fraction, which serves as a tracer of both tropospheric mixing and the efficiency of re-equilibration between the ortho- and para-hydrogen states, is slowly altering: super-equilibrium conditions (para-H2 fraction exceeding equilibrium expectations and suggestive of subsiding airmasses) that dominated the southern summer hemisphere are now weakening, whereas the sub-equilibrium conditions (suggestive of uplift) of the northern winter are being replaced by equilibrium or super-equilibrium conditions in spring. The thermal ‘knee’ and the para-H2 distribution are tracking both the increased spring illumination and the increasing tropospheric haze opacity of the springtime hemisphere

  7. Anatomic Distribution of Fluorodeoxyglucose-Avid Para-aortic Lymph Nodes in Patients With Cervical Cancer

    SciTech Connect

    Takiar, Vinita; Fontanilla, Hiral P.; Eifel, Patricia J.; Jhingran, Anuja; Kelly, Patrick; Iyer, Revathy B.; Levenback, Charles F.; Zhang, Yongbin; Dong, Lei; Klopp, Ann

    2013-03-15

    Purpose: Conformal treatment of para-aortic lymph nodes (PAN) in cervical cancer allows dose escalation and reduces normal tissue toxicity. Currently, data documenting the precise location of involved PAN are lacking. We define the spatial distribution of this high-risk nodal volume by analyzing fluorodeoxyglucose (FDG)-avid lymph nodes (LNs) on positron emission tomography/computed tomography (PET/CT) scans in patients with cervical cancer. Methods and Materials: We identified 72 PANs on pretreatment PET/CT of 30 patients with newly diagnosed stage IB-IVA cervical cancer treated with definitive chemoradiation. LNs were classified as left-lateral para-aortic (LPA), aortocaval (AC), or right paracaval (RPC). Distances from the LN center to the closest vessel and adjacent vertebral body were calculated. Using deformable image registration, nodes were mapped to a template computed tomogram to provide a visual impression of nodal frequencies and anatomic distribution. Results: We identified 72 PET-positive para-aortic lymph nodes (37 LPA, 32 AC, 3 RPC). All RPC lymph nodes were in the inferior third of the para-aortic region. The mean distance from aorta for all lymph nodes was 8.3 mm (range, 3-17 mm), and from the inferior vena cava was 5.6 mm (range, 2-10 mm). Of the 72 lymph nodes, 60% were in the inferior third, 36% were in the middle third, and 4% were in the upper third of the para-aortic region. In all, 29 of 30 patients also had FDG-avid pelvic lymph nodes. Conclusions: A total of 96% of PET positive nodes were adjacent to the aorta; PET positive nodes to the right of the IVC were rare and were all located distally, within 3 cm of the aortic bifurcation. Our findings suggest that circumferential margins around the vessels do not accurately define the nodal region at risk. Instead, the anatomical extent of the nodal basin should be contoured on each axial image to provide optimal coverage of the para-aortic nodal compartment.

  8. Astronomia para/com crianças carentes em Limeira

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.; Oliveira, V. C.

    2003-08-01

    Em 2001, o Instituto Superior de Ciências Aplicadas (ISCA Faculdades de Limeira) iniciou um projeto pelo qual o Observatório do Morro Azul empreendeu uma parceria com o Centro de Promoção Social Municipal (CEPROSOM), instituição mantida pela Prefeitura Municipal de Limeira para atender crianças e adolescentes carentes. O CEPROSOM contava com dois projetos: Projeto Centro de Convivência Infantil (CCI) e Programa Criança e Adolescente (PCA), que atendiam crianças e adolescentes em Centros Comunitários de diversas áreas da cidade. Esses projetos têm como prioridades estabelecer atividades prazerosas para as crianças no sentido de retirá-las das ruas. Assim sendo, as crianças passaram a ter mais um tipo de atividade - as visitas ao observatório. Este painel descreve as várias fases do projeto, que envolveu: reuniões de planejamento, curso de Astronomia para as orientadoras dos CCIs e PCAs, atividades relacionadas a visitas das crianças ao Observatório, proposta de construção de gnômons e relógios de Sol nos diversos Centros Comunitários de Limeira e divulgação do projeto na imprensa. O painel inclui discussões sobre a aprendizagem de crianças carentes, relatos que mostram a postura das orientadoras sobre a pertinência do ensino de Astronomia, relatos do monitor que fez o atendimento no Observatório e o que o número de crianças atendidas representou para as atividades da instituição desde o início de suas atividades e, em particular, em 2001. Os resultados são baseados na análise de relatos das orientadoras e do monitor do Observatório, registros de visitas e matérias da imprensa local. Conclui com uma avaliação do que tal projeto representou para as Instituições participantes. Para o Observatório, em particular, foi feita uma análise com relação às outras modalidades de atendimentos que envolvem alunos de escolas e público em geral. Também é abordada a questão do compromisso social do Observatório na educação do

  9. Differential regulation of ParaHox genes by retinoic acid in the invertebrate chordate amphioxus (Branchiostoma floridae).

    PubMed

    Osborne, Peter W; Benoit, Gérard; Laudet, Vincent; Schubert, Michael; Ferrier, David E K

    2009-03-01

    The ParaHox cluster is the evolutionary sister to the Hox cluster. Like the Hox cluster, the ParaHox cluster displays spatial and temporal regulation of the component genes along the anterior/posterior axis in a manner that correlates with the gene positions within the cluster (a feature called collinearity). The ParaHox cluster is however a simpler system to study because it is composed of only three genes. We provide a detailed analysis of the amphioxus ParaHox cluster and, for the first time in a single species, examine the regulation of the cluster in response to a single developmental signalling molecule, retinoic acid (RA). Embryos treated with either RA or RA antagonist display altered ParaHox gene expression: AmphiGsx expression shifts in the neural tube, and the endodermal boundary between AmphiXlox and AmphiCdx shifts its anterior/posterior position. We identified several putative retinoic acid response elements and in vitro assays suggest some may participate in RA regulation of the ParaHox genes. By comparison to vertebrate ParaHox gene regulation we explore the evolutionary implications. This work highlights how insights into the regulation and evolution of more complex vertebrate arrangements can be obtained through studies of a simpler, unduplicated amphioxus gene cluster. PMID:19103191

  10. ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation.

    PubMed

    Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta; Jakimowicz, Dagmara

    2016-04-01

    In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins. PMID:27248800

  11. ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation

    PubMed Central

    Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta

    2016-01-01

    In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces. To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins. PMID:27248800

  12. Aplicación del Teorema de Nekhorochev para tiempos de estabilidad en Mecánica Celeste

    NASA Astrophysics Data System (ADS)

    Miloni, O.; Núñez, J.; Brunini, A.

    En Mecánica Celeste, uno de los problemas centrales consiste en la determinación de los tiempos de estabilidad. El teorema de Nekhorochev proporciona un método para dicho estudio, para un sistema determinado por un hamiltoniano descripto en las variables acción-ángulo. El trabajo consiste en la acotación tanto del potencial perturbador y de la matriz hessiana del hamiltoniano integrable para determinar luego el tiempo de estabilidad de dicho sistema, donde por estabilidad se entiende la separación en norma infinito en el espacio de las acciones.

  13. Polar Effects Control the Gas-phase Reactivity of Charged para-Benzyne Analogs

    PubMed Central

    Wittrig, Ashley M.; Archibold, Enada F.; Sheng, Huaming; Nash, John J.; Kenttämaa, Hilkka I.

    2014-01-01

    The gas-phase reactivity of charged para-benzynes is entirely unexplored as they and/or their precursors tend to undergo ring-opening upon their generation. We report here a gas-phase reactivity study of two such benzynes, the 2,5-didehydropyridinium and 5,8-didehydroisoquinolinium cations, generated in a modified dual-linear quadrupole ion trap (DLQIT) mass spectrometer. Both biradicals were found to form diagnostic products with organic molecules, indicating the presence of two radical sites. As opposed to earlier predictions that the singlet-triplet (S-T) splitting controls the radical reactivity of such species, the 2,5-didehydropyridinium cation reacts much faster in spite of its larger S-T splitting. Calculated vertical electron affinities of the radical sites of the para-benzynes, a parameter related to the polarity of the transition states of their reactions, appears to be the most important reactivity controlling factor. PMID:25838787

  14. Development of an integrated remote monitoring technique and its application to para-stressing bridge system

    NASA Astrophysics Data System (ADS)

    Miyamoto, Ayaho; Motoshita, Minoru; Casas, Joan R.

    2013-12-01

    Bridge monitoring system via information technology is capable of providing more accurate knowledge of bridge performance characteristics than traditional strategies. This paper describes not only an integrated Internet monitoring system that consists of a stand-alone monitoring system (SMS) and a Web-based Internet monitoring system (IMS) for bridge maintenance but also its application to para-stressing bridge system as an intelligent structure. IMS, as a Web-based system, is capable of addressing the remote monitoring by introducing measuring information derived from SMS into the system through Internet or intranet connected by either PHS or LAN. Moreover, the key functions of IMS such as data management system, condition assessment, and decision making with the proposed system are also introduced in this paper. Another goal of this study is to establish the framework of a para-stressing bridge system which is an intelligent bridge by integrating the bridge monitoring information into the system to control the bridge performance automatically.

  15. Regioselective Enzymatic β-Carboxylation of para-Hydroxy- styrene Derivatives Catalyzed by Phenolic Acid Decarboxylases

    PubMed Central

    Wuensch, Christiane; Pavkov-Keller, Tea; Steinkellner, Georg; Gross, Johannes; Fuchs, Michael; Hromic, Altijana; Lyskowski, Andrzej; Fauland, Kerstin; Gruber, Karl; Glueck, Silvia M; Faber, Kurt

    2015-01-01

    We report on a ‘green’ method for the utilization of carbon dioxide as C1 unit for the regioselective synthesis of (E)-cinnamic acids via regioselective enzymatic carboxylation of para-hydroxystyrenes. Phenolic acid decarboxylases from bacterial sources catalyzed the β-carboxylation of para-hydroxystyrene derivatives with excellent regio- and (E/Z)-stereoselectivity by exclusively acting at the β-carbon atom of the C=C side chain to furnish the corresponding (E)-cinnamic acid derivatives in up to 40% conversion at the expense of bicarbonate as carbon dioxide source. Studies on the substrate scope of this strategy are presented and a catalytic mechanism is proposed based on molecular modelling studies supported by mutagenesis of amino acid residues in the active site. PMID:26190963

  16. Charge-transfer-directed radical substitution enables para-selective C–H functionalization

    NASA Astrophysics Data System (ADS)

    Boursalian, Gregory B.; Ham, Won Seok; Mazzotti, Anthony R.; Ritter, Tobias

    2016-08-01

    Efficient C–H functionalization requires selectivity for specific C–H bonds. Progress has been made for directed aromatic substitution reactions to achieve ortho and meta selectivity, but a general strategy for para-selective C–H functionalization has remained elusive. Herein we introduce a previously unappreciated concept that enables nearly complete para selectivity. We propose that radicals with high electron affinity elicit arene-to-radical charge transfer in the transition state of radical addition, which is the factor primarily responsible for high positional selectivity. We demonstrate with a simple theoretical tool that the selectivity is predictable and show the utility of the concept through a direct synthesis of aryl piperazines. Our results contradict the notion, widely held by organic chemists, that radical aromatic substitution reactions are inherently unselective. The concept of radical substitution directed by charge transfer could serve as the basis for the development of new, highly selective C–H functionalization reactions.

  17. Una propuesta para el desarrollo de un arreglo de síntesis de apertura

    NASA Astrophysics Data System (ADS)

    Arnal, E. M.

    Los estudios llevados a cabo en la transición del hidrógeno neutro a λ~21-cm han contribuído a incrementar nuestro conocimiento acerca de las propiedades globales del medio interestelar, sea este galáctico o extragaláctico. Avances en este campo han sido provocados, a menudo, por la puesta en servicio de radiotelescopios que poseen una mayor resolución angular. Aquí se presenta una propuesta para desarrollar un nuevo instrumento, un interferómetro, que permitirá abrir nuevas líneas de investigación. Este instrumento combinará la técnica de síntesis de apertura con la de espectroscopía de correlación digital, para alcanzar una resolución angular de 1' y un campo de visión de ~1o.7.

  18. Charge-transfer-directed radical substitution enables para-selective C-H functionalization.

    PubMed

    Boursalian, Gregory B; Ham, Won Seok; Mazzotti, Anthony R; Ritter, Tobias

    2016-08-01

    Efficient C-H functionalization requires selectivity for specific C-H bonds. Progress has been made for directed aromatic substitution reactions to achieve ortho and meta selectivity, but a general strategy for para-selective C-H functionalization has remained elusive. Herein we introduce a previously unappreciated concept that enables nearly complete para selectivity. We propose that radicals with high electron affinity elicit arene-to-radical charge transfer in the transition state of radical addition, which is the factor primarily responsible for high positional selectivity. We demonstrate with a simple theoretical tool that the selectivity is predictable and show the utility of the concept through a direct synthesis of aryl piperazines. Our results contradict the notion, widely held by organic chemists, that radical aromatic substitution reactions are inherently unselective. The concept of radical substitution directed by charge transfer could serve as the basis for the development of new, highly selective C-H functionalization reactions. PMID:27442288

  19. Molecular Characterization of Neurally Expressing Genes in the Para Sodium Channel Gene Cluster of Drosophila

    PubMed Central

    Hong, C. S.; Ganetzky, B.

    1996-01-01

    To elucidate the mechanisms regulating expression of para, which encodes the major class of sodium channels in the Drosophila nervous system, we have tried to locate upstream cis-acting regulatory elements by mapping the transcriptional start site and analyzing the region immediately upstream of para in region 14D of the polytene chromosomes. From these studies, we have discovered that the region contains a cluster of neurally expressing genes. Here we report the molecular characterization of the genomic organization of the 14D region and the genes within this region, which are: calnexin (Cnx), actin related protein 14D (Arp14D), calcineurin A 14D (CnnA14D), and chromosome associated protein (Cap). The tight clustering of these genes, their neuronal expression patterns, and their potential functions related to expression, modulation, or regulation of sodium channels raise the possibility that these genes represent a functionally related group sharing some coordinate regulatory mechanism. PMID:8849894

  20. Control of Photoluminescence of Carbon Nanodots via Surface Functionalization using Para-substituted Anilines

    PubMed Central

    Kwon, Woosung; Do, Sungan; Kim, Ji-Hee; Seok Jeong, Mun; Rhee, Shi-Woo

    2015-01-01

    Carbon nanodots (C-dots) are a kind of fluorescent carbon nanomaterials, composed of polyaromatic carbon domains surrounded by amorphous carbon frames, and have attracted a great deal of attention because of their interesting properties. There are still, however, challenges ahead such as blue-biased photoluminescence, spectral broadness, undefined energy gaps and etc. In this report, we chemically modify the surface of C-dots with a series of para-substituted anilines to control their photoluminescence. Our surface functionalization endows our C-dots with new energy levels, exhibiting long-wavelength (up to 650 nm) photoluminescence of very narrow spectral widths. The roles of para-substituted anilines and their substituents in developing such energy levels are thoroughly studied by using transient absorption spectroscopy. We finally demonstrate light-emitting devices exploiting our C-dots as a phosphor, converting UV light to a variety of colors with internal quantum yields of ca. 20%. PMID:26218869

  1. Sludge reduction by uncoupling metabolism: SBR tests with para-nitrophenol and a commercial uncoupler.

    PubMed

    Zuriaga-Agustí, E; Mendoza-Roca, J A; Bes-Piá, A; Alonso-Molina, J L; Amorós-Muñoz, I

    2016-11-01

    Nowadays cost reduction is a very important issue in wastewater treatment plants. One way, is to minimize the sludge production. Microorganisms break down the organic matter into inorganic compounds through catabolism. Uncoupling metabolism is a method which promote catabolism reactions instead of anabolism ones, where adenosine triphosphate synthesis is inhibited. In this work, the influence of the addition of para-nitrophenol and a commercial reagent to a sequencing batch reactor (SBR) on sludge production and process performance has been analyzed. Three laboratory SBRs were operated in parallel to compare the effect of the addition of both reagents with a control reactor. SBRs were fed with synthetic wastewater and were operated with the same conditions. Results showed that sludge production was slightly reduced for the tested para-nitrophenol concentrations (20 and 25 mg/L) and for a LODOred dose of 1 mL/day. Biological process performance was not influenced and high COD removals were achieved. PMID:27505165

  2. ROTATIONAL SPECTROSCOPY OF THE CO-PARA-H{sub 2} MOLECULAR COMPLEX

    SciTech Connect

    Potapov, A. V.; Surin, L. A.; Giesen, T. F.; Schlemmer, S.; Panfilov, V. A.; Dumesh, B. S.; Raston, P. L.; Jaeger, W.

    2009-10-01

    The rotational spectrum of the CO-para-H{sub 2} van der Waals complex, produced using a molecular jet expansion, was observed with two different techniques: OROTRON intracavity millimeter-wave spectroscopy and pulsed Fourier transform microwave spectroscopy. Thirteen transitions in the frequency range from 80 to 130 GHz and two transitions in the 14 GHz region were measured and assigned, allowing for a precise determination of the corresponding energy level positions of CO-para-H{sub 2}. The data obtained enable further radio astronomical searches for this molecular complex and provide a sensitive test of the currently best available intermolecular potential energy surface for the CO-H{sub 2} system.

  3. Repeated Topical Application of para-Phenylenediamine Induces Renal Histopathological Changes in Rats.

    PubMed

    Bharali, Manuj Kr; Basumatary, Rajeev; Rahman, Taibur; Dutta, Karabi

    2012-05-01

    Hemolytic anemia and rhabdomyolysis have been often reported to be an adverse effect of drug- and chemical-induced toxicity both in experimental and real-life scenario. para-Phenylenediamine (PPD) is a derivative of para-nitroaniline and has been found as an ingredient of almost all hair dye formulations in varying concentrations from 2% to 4% w/v. Earlier studies have reported that the accidental oral ingestion of PPD in humans can lead to acute renal failure because of rhabdomyolysis. In the present investigation, we have tested the chronic topical application of PPD and its effect on the renal histology of Sprague-Dawley rats. The experiment provides clear evidence that topically applied PPD induces hemolytic anemia as evident from the decrease in the total RBC count, packed cell volume, and hemoglobin content apart from rhabdomyolysis which subsequently causes acute renal failure in rats. PMID:22778510

  4. Parallel Visualization and Analysis with ParaView on a Cray XT4

    SciTech Connect

    Patchett, John; Ahrens, James; Ahern, Sean; Pugmire, Dave

    2009-01-01

    Scienti c data sets produced by modern supercomputers like ORNL s Cray XT 4, Jaguar, can be extremely large, making visualization and analysis more di cult as moving large resultant data to dedicated analysis systems can be pro- hibitively expensive. We share our continuing work of integrating a parallel visu- alization system, ParaView, on ORNL s Jaguar system and our e orts to enable extreme scale interactive data visualization and analysis. We will discuss porting challenges and present performance numbers.

  5. Conformerism, enantiomorphism and double catemer motifs in para-substituted nostoclide analogues

    NASA Astrophysics Data System (ADS)

    Teixeira, Róbson Ricardo; Barbosa, Luiz Claudio Almeida; Valero Antolinez, Isabel; de Souza Corrêa, Rodrigo; Martins, Felipe Terra; Doriguetto, Antônio Carlos

    2016-02-01

    We have here elucidated the crystal structures of five nostoclide analogues. A common feature in all compounds is a substituent at the para-position of the benzylidene group. Compounds with either bromine (3) or hydroxyl (4) as para-substituent crystallizes with Z' = 2 as result of conformerism. It was also observed that Z' > 1 in the compound with a para-dimethylamino substituent (1). However, its four crystallographically independent molecules are conformationally similar. They are not related by crystallographic symmetry due to the offset packing of their C-H … Odbnd C nonclassical hydrogen bonded double chains. This compound (1) has also crystallized in a chiral space group (P21) despite the lack of a stereocenter. Such enantiomorphism phenomenon is related to the presence of only one of the two mirror benzyl conformations with phenyl ring at the equatorial position opposite the lactone oxygen atom. The molecular mean plane of nostoclide analogues has been featured by high level of planarity, except in the brominated compound where two twisted conformations occurred due to rotations on the single bond axis into benzylidene group. The benzyl conformation has been the greatest difference between the two crystallographically independent molecules of the para-hydroxylated compound (4). The crystal packing of the compounds is marked by double catemer motif assembled through C-H … Odbnd C non-classical hydrogen bonds, although C-H … π interactions do play an important role in stabilizing the crystal packing of some compounds of the series.

  6. Highly regioselective para-methylthiolation/bridging methylenation of arylamines promoted by NH4I.

    PubMed

    Xu, Yinfeng; Cong, Tiantian; Liu, Ping; Sun, Peipei

    2015-10-14

    Aryl methyl thioethers and methylene-bridged arylamines were synthesized via highly regioselective para-methylthiolation/bridging methylenation of arylamines using DMSO as the methylthio or methylene source in the presence of NH4I under metal-free conditions. For the substrates with both electron-donating and electron-withdrawing substituents, the reaction proceeded smoothly and gave moderate to good yields. PMID:26337143

  7. Stimulated rotational Raman scattering in CO2-pumped para-H2

    SciTech Connect

    Carlsten, J.L.; Wenzel, R.G.

    1983-09-01

    Stimulated rotational Raman scattering in a 300 K multipass cell filled with para-H2 with a single-mode CO2 pump laser was studied using a single-mode OPO as a probe laser at the Stokes frequency for the So(0) transition. Amplification and pump depletion are examined as a function of incident pump energy. For an incident CO2 pump laser energy of 1.5 J, a photon conversion efficiency of 47 percent is observed.

  8. ParaDiS on Blue Gene/L: stepping up to the challenge

    SciTech Connect

    Hommes, G; Arsenlis, A; Bulatov, V; Cai, W; Cook, R; Hiratani, M; Oppestrup, T; Rhee, M; Tang, M

    2006-06-09

    This paper reports on the efforts to enable fully scalable simulations of Dislocation Line Dynamics (DLD) for direct calculations of strength of crystalline materials. DLD simulations are challenging and do not lend themselves naturally to parallel computing. Through a combinations of novel physical approaches, mathematical algorithms and computational science developments, a new DLD code ParaDiS is shown to take meaningful advantage of BG/L and, by doing so, to enable discovery class science by computation.

  9. Cáncer de cuello uterino—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento, la prevención, las causas y los exámenes de detección del cáncer de cuello uterino, así como referencias a estudios clínicos, investigación, estadísticas y otros temas relacionados.

  10. Iodine(III)-Mediated para-Selective Direct Imidation of Anilides.

    PubMed

    Pialat, Amélie; Bergès, Julien; Sabourin, Axel; Vinck, Robin; Liégault, Benoît; Taillefer, Marc

    2015-07-01

    The direct, nucleophilic imidation of acetanilide derivatives has been performed under mild, iodine(III)-mediated or -catalyzed conditions, employing lithium triflimide as the nitrogen source. The reaction exhibits exclusive regioselectivity for the para position and shows a good tolerance for varied functional groups at both the ortho or meta positions. Preliminary mechanistic data suggest that the LiNTf2 reagent plays a key role in the reactivity. PMID:26095155

  11. Synthesis of icariin from kaempferol through regioselective methylation and para-Claisen-Cope rearrangement.

    PubMed

    Mei, Qinggang; Wang, Chun; Zhao, Zhigang; Yuan, Weicheng; Zhang, Guolin

    2015-01-01

    The hemisynthesis of the naturally occurring bioactive flavonoid glycoside icariin (1) has been accomplished in eleven steps with 7% overall yield from kaempferol. The 4'-OH methylation of kaempferol, the 8-prenylation of 3-O-methoxymethyl-4'-O-methyl-5-O-prenyl-7-O-benzylkaempferol (8) via para-Claisen-Cope rearrangement catalyzed by Eu(fod)3 in the presence of NaHCO3, and the glycosylation of icaritin (3) are the key steps. PMID:26425179

  12. Stable self-trapping and ring formation in polydiacetylene para-toluene sulfonate

    NASA Astrophysics Data System (ADS)

    Wright, Ewan M.; Lawrence, Brian L.; Torruellas, William; Stegeman, George

    1995-12-01

    Numerical simulations of two-dimensional beam propagation in polydiacetylene para-toluene sulfonate measured values for n2>0 and n3<0 , where Delta n=n2I+n 3I2 , predict stable self-trapping and a new phenomenon in which a spatial ring evolves from a Gaussian input beam. We interpret the numerical results theoretically, using the variational model of nonlinear Gaussian beam propagation.

  13. Towards physical interpretation of substituent effects: the case of meta- and para-substituted anilines.

    PubMed

    Szatylowicz, Halina; Siodla, Tomasz; Stasyuk, Olga A; Krygowski, Tadeusz M

    2016-04-28

    Quantum chemical modeling was used to investigate the electron-donating properties of the amino group in a series of meta- and para-X-substituted anilines (X = NMe2, NH2, OH, OMe, CH3, H, F, Cl, CF3, CN, CHO, COMe, CONH2, COOH, NO2, and NO). Different methods (HF, B3LYP, and M06-2X) and basis sets (6-31+G(d,p), 6-311++G(d,p), and aug-cc-pVDZ) were applied and compared with the MP2 approach. The B3LYP/6-311++G(d,p) method was chosen as the most appropriate one. The substituent properties were described by σ, cSAR(X) and SESE descriptors; the amino group was characterized by structural (dCN, dNH and ΣNH2) and electronic [δ(N) and cSAR(NH2)] parameters; whereas the transmitting moiety was characterized by aromaticity indices HOMA and NICS, as well as by QTAIM characteristics at the ring critical point. All the used parameters were found to be mutually interrelated with much better correlations for the para-derivatives than the meta-derivatives. It was numerically confirmed that sensitivity of the amino group to the substituent effect was greater by over three times when the substituent was located in the para-position. In the case of the meta-derivatives, variability of characteristics for both the reaction center and the substituent was small. The reverse substituent effect was clearly shown by comparison of the cSAR(X) characteristics for monosubstituted benzenes, and meta- and para-substituted anilines. PMID:26725941

  14. Cáncer de pulmón—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento, la prevención, las causas y los exámenes de detección del cáncer de pulmón, así como referencias a estudios clínicos, investigación, estadísticas y otros temas

  15. ParaDiS on BlueGene/L: scalable line dynamics

    SciTech Connect

    Bulatov, V; Cai, W; Fier, J; Hiratani, M; Pierce, T; Tang, M; Rhee, M; Yates, R K; Arsenlis, A

    2004-04-29

    We describe an innovative highly parallel application program, ParaDiS, which computes the plastic strength of materials by tracing the evolution of dislocation lines over time. We discuss the issues of scaling the code to tens of thousands of processors, and present early scaling results of the code run on a prototype of the BlueGene/L supercomputer being developed by IBM in partnership with the US DOE's ASC program.

  16. The ortho:para-H_2 ratio in C- and J-type shocks

    NASA Astrophysics Data System (ADS)

    Wilgenbus, D.; Cabrit, S.; Pineau des Forêts, G.; Flower, D. R.

    2000-04-01

    We have computed extensive grids of models of both C- and J-type planar shock waves, propagating in dark, cold molecular clouds, in order to study systematically the behaviour of the ortho:para-H_2 ratio. Careful attention was paid to both macroscopic (dynamical) and microscopic (chemical reactions and collisional population transfer in H_2) aspects. We relate the predictions of the models to observational determinations of the ortho:para-H_2 ratio using both pure rotational lines and rovibrational lines. As an illustration, we consider ISO and ground-based H_2 observations of HH 54. Neither planar C-type nor planar J-type shocks appear able to account fully for these observations. Given the additional constraints provided by the observed ortho:para H_2 ratios, a C-type bowshock, or a C-type precursor followed by a J-type shock, remain as plausible models. Tables~2a-f and 4a-f are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

  17. Theoretical study of the design of a catalyst for para to ortho hydrogen conversion

    NASA Technical Reports Server (NTRS)

    Coffman, Robert E.

    1992-01-01

    The theory of Petzinger and Scalapino (1973) was thoroughly reviewed, and all of the basic equations for paramagnetic para to ortho hydrogen catalysis re-derived. There are only a few minor phase errors and errors of omission in the description of the theory. Three models (described by Petzinger and Scalapino) for the rate of para to ortho H2 catalysis were worked out, and uniform agreement obtained to within a constant factor of 2 pi. The analytical methods developed in the course of this study were then extended to two new models, which more adequately describe the process of surface catalysis including transfer of hydrogen molecules onto and off of the surface. All five equations for the para to ortho catalytic rate of conversion are described. The two new equations describe the catalytic rate for these models: H2 on the surface is a 2-D gas with lifetime tau; and H2 on the surface is a 2-D liquid undergoing Brownian motion (diffusion) with surface lifetime tau.

  18. The ortho:para ratio of H{sub 3}{sup +} in laboratory and astrophysical plasmas

    SciTech Connect

    Crabtree, Kyle N.; Indriolo, Nick; Kreckel, Holger; McCall, Benjamin J.

    2015-01-22

    The discovery of H{sub 3}{sup +} in the diffuse interstellar medium has dramatically changed our view of the cosmic-ray ionization rate in diffuse molecular clouds. However, another surprise has been that the ortho:para ratio of H{sub 3}{sup +} in these clouds is inconsistent with the temperature derived from the excitation of H{sub 2}, the dominant species in these clouds. In an effort to understand this discrepancy, we have embarked on an experimental program to measure the nuclear spin dependence of the dissociative electron recombination rate of H{sub 3}{sup +} using the CRYRING and TSR ion storage rings. We have also performed the first measurements of the reaction H{sub 3}{sup +}+H{sub 2}→H{sub 2}+H{sub 3}{sup +} below room temperature. This reaction is likely the most common bimolecular reaction in the universe, and plays an important role in interconverting ortho- and para-H{sub 3}{sup +}. Finally, we have constructed a steady-state chemical model for diffuse clouds, which takes into account the spin-dependence of the formation of H{sub 3}{sup +}, its electron recombination, and its reaction with H{sub 2}. We find that the ortho:para ratio of H{sub 3}{sup +} in diffuse clouds is likely governed by a competition between dissociative recombination and thermalization by reactive collisions.

  19. ParaGard gets mixed reviews at one-year anniversary.

    PubMed

    1989-07-01

    IUDs fill a need for reliable convenient contraceptives in multiparous, monogamous women who have no history of ectopic pregnancy, pelvic inflammatory disease, or sexually transmitted disease, and who are primarily interested in birth spacing or who have completed their family and do not opt for sterilization. The only IUDs currently available in the US are Progestasert, a progestin-releasing device that must be replaced after 1 year, and ParaGard, a copper-bearing device manufactured by GynoPharma, that can be left in place for up to 4 years. IUD use has declined in the US because of adverse publicity and lawsuits. Both IUDs have problems with insertion. There is an incidence of 1.8 cervical lacerations for every 100 insertions, and the ParaGard inserter is likely to drop to the floor if the clinician fails to use the thumb ring, which is designed to keep it from doing so. ParaGard is accompanied by a 5-page consent form to protect the manufacturer, which deters many women. Prophylactic administration of antibiotics before insertion is recommended, and some clinicians recommend ibuprofen to prevent inflammation. Both IUDs cost about $80. PMID:12282179

  20. Quantum chemical and experimental study of 1,2,4-trihydroxy-para-menthane

    NASA Astrophysics Data System (ADS)

    Rottmannová, Lenka; Lukeš, Vladimír; Ilčin, Michal; Fodran, Peter; Herich, Peter; Kožíšek, Jozef; Liptaj, Tibor; Klein, Erik

    2013-10-01

    The conformational analysis of the para-menthane (PM) and 1,2,4-trihydroxy-para-menthane (TPM) is performed using the quantum chemical density functional theory (DFT) and ab initio Møller-Plesset perturbation theory up to the second order (MP2). In TPM, three hydroxyl groups generate eight stereoisomers comparing to the four para-menthane stereoisomers. From the thermodynamics point of view, the most preferred conformations show the chair-shaped configuration of the cyclohexane ring. The obtained energy barriers for the isopropyl group rotation in the chair-shaped stereoisomers are between 35 and 45 kJ mol-1. The crystal structure as well as the solvated TPM stereoisomer isolated from the Tea tree oil, Melaleuca alternifolia (Maiden & Betche) Cheel, were investigated experimentally. Isolated stereoisomer corresponds to the most energetically preferred conformation and the calculated structural data agree very well with the results from the X-ray and nuclear magnetic resonance measurements. Finally, the influence of the conformation and the presence of the intramolecular hydrogen bonds on the homolytic Osbnd H bond dissociation enthalpies and proton affinities were also discussed with respect to the simple alcohols (methanol, iso-propanol, iso-pentanol, tert-butanol, cyclohexanol) and phenol.

  1. Atlas de aves: Un metodo para documentar distribucion y seguir poblaciones

    USGS Publications Warehouse

    Robbins, C.S.; Dowell, B.A.; Dawson, D.K.

    1988-01-01

    Los Atlas de Aves son proyectos nacionales o regionalies para trazar en mapas la distribucion en reproduccion de cada especie de ave. Ese procedimiento se esta usando en Europa, Australia, Nueva Zelanda, Norteamerica, y partes de Africa. El tama?o de los cuadrados varia de medio grado de latitud y Iongitud hasta 5 x 5 km. El trabajo de campo de cada proyecto exige aproxlmadamente cinco a?os, pero los aficionados pueden llevar a cabo la mayor parte del trabajo. Es posible almacenar los resultados en un computador personal. Hay muchos beneficios: (I) se presenta la distribucion corriente de las aves de la nacion, del estado, o de la Iocalidad; (2) se desarrolla nueva informacion especialmente sobre especies raras o en peligro; (3) se descubren areas que tienen una avlfauna sobresaliente o habitats raros y ayuda a su proteccion, (4) se documentan cambios de dlstribucion; (5) se pueden usar para documentar cambios de poblacion, especialmente en los tropicos donde otros metodos son mas dificiles de usar porque hay muchas especies y no hay muchos observadores calificados en la identificacion de sonidos de las aves; (6) son proyectos buenos de investigacion para estudiantes graduados; (7) los turistas y los jefes de excursiones de historia natural pueden contribuir con muchas informaciones

  2. Consistent assignment of the vibrations of symmetric and asymmetric para-disubstituted benzene molecules

    NASA Astrophysics Data System (ADS)

    Andrejeva, Anna; Gardner, Adrian M.; Tuttle, William D.; Wright, Timothy G.

    2016-03-01

    We give a description of the phenyl-ring-localized vibrational modes of the ground states of the para-disubstituted benzene molecules including both symmetric and asymmetric cases. In line with others, we quickly conclude that the use of Wilson mode labels is misleading and ambiguous; we conclude the same regarding the related ones of Varsányi. Instead we label the modes consistently based upon the Mulliken (Herzberg) method for the modes of para-difluorobenzene (pDFB). Since we wish the labelling scheme to cover both symmetrically- and asymmetrically-substituted molecules, we apply the Mulliken labelling under C2v symmetry. By studying the variation of the vibrational wavenumbers with mass of the substituent, we are able to identify the corresponding modes across a wide range of molecules and hence provide consistent assignments. Particularly interesting are pairs of vibrations that evolve from in- and out-of-phase motions in pDFB to more localized modes in asymmetric molecules. We consider the para isomers of the following: the symmetric dihalobenzenes, xylene, hydroquinone, the asymmetric dihalobenzenes, halotoluenes, halophenols and cresol.

  3. Effects of para-substituents of styrene derivatives on their chemical reactivity on platinum nanoparticle surfaces.

    PubMed

    Hu, Peiguang; Chen, Limei; Deming, Christopher P; Lu, Jia-En; Bonny, Lewis W; Chen, Shaowei

    2016-06-01

    Stable platinum nanoparticles were successfully prepared by the self-assembly of para-substituted styrene derivatives onto the platinum surfaces as a result of platinum-catalyzed dehydrogenation and transformation of the vinyl groups to the acetylene ones, forming platinum-vinylidene/-acetylide interfacial bonds. Transmission electron microscopic measurements showed that the nanoparticles were well dispersed without apparent aggregation, suggesting sufficient protection of the nanoparticles by the organic capping ligands, and the average core diameter was estimated to be 2.0 ± 0.3 nm, 1.3 ± 0.2 nm, and 1.1 ± 0.2 nm for the nanoparticles capped with 4-tert-butylstyrene, 4-methoxystyrene, and 4-(trifluoromethyl)styrene, respectively, as a result of the decreasing rate of dehydrogenation with the increasing Taft (polar) constant of the para-substituents. Importantly, the resulting nanoparticles exhibited unique photoluminescence, where an increase of the Hammett constant of the para-substituents corresponded to a blue-shift of the photoluminescence emission, suggesting an enlargement of the HOMO-LUMO band gap of the nanoparticle-bound acetylene moieties. Furthermore, the resulting nanoparticles exhibited apparent electrocatalytic activity towards oxygen reduction in acidic media, with the best performance among the series of samples observed with the 4-tert-butylstyrene-capped nanoparticles due to an optimal combination of the nanoparticle core size and ligand effects on the bonding interactions between platinum and oxygen species. PMID:27242019

  4. The "drinking-buddy" scale as a measure of para-social behavior.

    PubMed

    Powell, Larry; Richmond, Virginia P; Cantrell-Williams, Glenda

    2012-06-01

    Para-social behavior is a form of quasi-interpersonal behavior that results when audience members develop bonds with media personalities that can resemble interpersonal social interaction, but is not usually applied to political communication. This study tested whether the "Drinking-Buddy" Scale, a simple question frequently used in political communication, could be interpreted as a single-item measure of para-social behavior with respect to political candidates in terms of image judgments related to interpersonal attraction and perceived similarity to self. The participants were college students who had voted in the 2008 election. They rated the candidates, Obama or McCain, as drinking buddies and then rated the candidates' perceived similarity to themselves in attitude and background, and also the social and task attraction to the candidate. If the drinking-buddy rating serves as a proxy measure for para-social behavior, then it was expected that participants' ratings for all four kinds of similarity to and attraction toward a candidate would be higher for the candidate they chose as a drinking buddy. The directional hypotheses were supported for interpersonal attraction, but not for perceived similarity. These results indicate that the drinking-buddy scale predicts ratings of interpersonal attraction, while voters may view perceived similarity as an important but not essential factor in their candidate preference. PMID:22897105

  5. Single crystalline nature of para-sexiphenyl crystallites grown on KCl(100).

    PubMed

    Haber, T; Oehzelt, M; Resel, R; Andreev, A; Thierry, A; Sitter, H; Smilgies, D M; Schaffer, B; Grogger, W; Resel, R

    2006-03-01

    This work focuses on studies of the single crystal nature of para-sexiphenyl structures grown on freshly cleaved KCl(100) surfaces. Two different kinds of morphologies, namely terrace like structures and needle like structures, are found by atomic force microscopy as well as by electron microscopy. Regardless of the morphology the individual crystallites show highly regular shapes. The crystalline alignment and the degree of order of the crystallites on the surface are determined by X-ray diffraction. Several epitaxial alignments of para-sexiphenyl on KCl(100) are observed and all of them are perfectly aligned on the surface. The rocking curve widths of the organic crystallites do not exceed 800" which is approximately only the four fold of the substrates' ones. The single crystalline nature of para-sexiphenyl crystallites is proven by transmission electron microscopy, diffraction patterns, dark field imaging and high resolution techniques. Single crystalline terraced mounds reach diameters of several microns and heights of 50 nm. Single crystal needles show heights and breadths of more than 100 nm and lengths of several microns. PMID:16573123

  6. El diseño final del espectrógrafo de banco (EBASIM) para CASLEO

    NASA Astrophysics Data System (ADS)

    Simmons, J.; Levato, H.

    Utilizando el código de óptica ACCOS V se ha finalizado el diseño del espectrógrafo de banco para CASLEO. En una comunicación anterior habíamos indicado que utilizaríamos un colimador de 150 mm de diámetro con un radio de curvatura de 1540 mm. Para el espejo cámara, que tiene un diámetro de 200 mm, el radio de curvatura es de 1200 mm, ambos radios con una tolerancia no mayor a los 3 mm. En la presente, se informa sobre los detalles finales del cálculo del espectrógrafo que incluye el cómputo para 5 longitudes de onda diferentes y alrededor de 100 rayos. En todos los casos el 75 % de energía está dentro de un diámetro de 13 micrones. El diseño ha sido probado entre 3500 Å hasta 9000 Å con resultados satisfactorios.

  7. Base de linhas moleculares para síntese espectral estelar

    NASA Astrophysics Data System (ADS)

    Milone, A.; Sanzovo, G.

    2003-08-01

    A análise das abundâncias quí micas fotosféricas em estrelas do tipo solar ou tardia, através do cálculo teórico de seus espectros, emprega a espectroscopia de alta resolução e necessita de uma base representativa de linhas atômicas e moleculares com suas respectivas constantes bem determinadas. Nesse trabalho, utilizamos como ponto de partida as extensas listas de linhas espectrais de sistemas eletrônicos de algumas moléculas diatômicas compiladas por Kurucz para a construção de uma base de linhas moleculares para a sí ntese espectral estelar. Revisamos as determinações dos fatores rotacionais de Honl-London das forças de oscilador das linhas moleculares, para cada banda vibracional de alguns sistemas eletrônicos, seguindo a regra usual de normalização. Usamos as forças de oscilador eletrônicas da literatura. Os fatores vibracionais de Franck-Condon de cada banda foram especialmente recalculados empregando-se novas constantes moleculares. Reproduzimos, com êxito, as absorções espectrais de determinadas bandas eletrônicas-vibracionais das espécies moleculares C12C12, C12N14 e Mg24H em espectros de estrelas de referência como o Sol e Arcturus.

  8. Neoplasias mieloproliferativas y síndromes mielodisplásicos—Versión para profesionales de salud

    Cancer.gov

    Información del Instituto Nacional del Cáncer para profesionales de salud sobre el tratamiento de las neoplasias mieloproliferativas, así como referencias a estudios clínicos y otros temas relacionados.

  9. Quantum Monte Carlo Simulation of Vibrational Frequency Shifts of CO in Solid para-HYDROGEN

    NASA Astrophysics Data System (ADS)

    Wang, Lecheng; Le Roy, Robert; Roy, Pierre-Nicholas

    2014-06-01

    Stimulated by Fajardo's remarkable study of the rovibrational spectra of CO isotopologues trapped in solid para-hydrogen, we have performed quantum Monte Carlo simulations to predict his observed vibrational frequency shifts and inertial rotational constants using 2-body potentials based on the best available models for the pH_2-pH_2 and CO-pH_2, potential energy functions. We started by fitting an analytic `Morse/Long-Range' (MLR) function to the 1D ``adiabaic hindered rotor" version of Hinde's 5D pH_2-pH_2 potential developed by Faruk et al. We then modified it to take account of many-body effects by scaling it until it yielded the correct equilibrium lattice parameters for the fcc and hcp structures of pure solid para-hydrogen. A CO molecule was then placed at different interstitial or substitution sites in large equilibrated fcc or hcp para-hydrogen lattices, and the structural and dynamical behaviors of the micro-solvation environment around CO were simulated with a PIMC algorithm using a 2D effective pH_2-CO potential based on the 5D H_2--CO potential energy surface recently reported by Li et al., with a lattice sum of values of the 2D CO vibrational difference potential being use to predict the vibrational frequency shift. The effective rotational constants Beff for CO in different solid para-hydrogen structures were also calculated and compared with the experimental observations and with predicted Beff values for CO in large-sized para-hydrogen--CO clusters. M. E. Fajardo, J. Phys. Chem. A 117, 13504 (2013). R. Hinde, J. Chem. Phys., 128, 154308 (2008). H. Li, X-L. Zhang, R.J. Le Roy, and P.-N. Roy, J. Chem. Phys. 139, 164315 (2013). R.J. Le Roy, C.C. Haugen, J. Tao and Hui Li, Mol. Phys., 109, 435 (2011) N. Faruk, R.J. Le Roy, and P.-N. Roy, J. Chem. Phys. (submitted December 2013). Y. Mizumoto and Y. Ohtsuki, Chem. Phys. Lett. 501, 304 (2011).

  10. Implementação de um algoritmo para a limpeza de mapas da RCFM

    NASA Astrophysics Data System (ADS)

    Souza, C. L.; Wuensche, C. A.

    2003-08-01

    A Radiação Cósmica de Fundo em Microondas (RCFM), descoberta por Penzias e Wilson em 1965, é uma das ferramentas mais poderosas para o estudo da cosmologia. Com a descoberta de flutuações de temperatura na RCFM, da ordem de uma parte em 105, pelo COBE (1992), uma nova era teve início. Nos últimos onze anos, diversos instrumentos fizeram novas medidas de alta precisão, refinando os resultados apresentados pelo COBE, culminando com os resultados recentes do satélite WMAP. A análise de dados da RCFM, especialmente no caso de experimentos com pequena cobertura do céu, apresenta uma série de dificuldades devido a emissões de contaminantes externos, tais como a emissão da Galáxia e de fontes pontuais, e de ruídos intrínsecos tanto ao sistema de detecção quanto à estratégia de observação do céu. Uma das soluções típicas para a filtragem de dados brutos de um experimento para medir flutuações de temperatura é aplicar um gabarito (template) e um filtro passa alta ao produzir mapas simplificados (sem considerar matrizes de correlação ou covariância). No caso de experimentos que utilizam detectores HEMT, essa combinação de filtros remove, satisfatoriamente, ruídos do tipo 1/f gerados pela instabilidade no ganho do detector acoplado ao movimento do instrumento, definido pela estratégia de observação. Entretanto, o sinal resultante medido, tanto em simulações quanto em séries temporais reais, sugere que parte do sinal cosmológico pode estar sendo removido junto com o ruído dos detectores. Este trabalho descreve as etapas para a produção de um mapa típico (simulado) e os testes preliminares de um algoritmo para remover ruídos do tipo 1/f introduzidos pela estratégia de observação sem prejudicar a qualidade do sinal cosmológico presente no mapa.