Sosa-Rubí, Sandra G; Salinas-Rodríguez, Aarón; Galárraga, Omar
2016-01-01
Objetivo Estimar el efecto del Seguro Popular (SP) sobre la incidencia del gasto catastrófico en salud (GCS) y sobre el gasto de bolsillo en salud (GBS) en el mediano plazo. Material y métodos Con base en la Encuesta de Evaluación del Seguro Popular (2005–2008), se analizaron los resultados del efecto del SP en la cohorte rural para dos años de seguimiento (2006 y 2008) y en la cohorte urbana para un año (2008). Resultados A nivel conglomerado no se detectaron efectos del SP. A nivel hogar se encontró que el SP tiene un efecto protector en el GCS y en el GBS en consulta externa y hospitalización en zonas rurales; y efectos significativos en la reducción de GBS en consulta externa en zonas urbanas. Conclusiones El SP se muestra como un programa efectivo para proteger a los hogares contra gastos de bolsillo por motivos de salud en el mediano plazo. PMID:22282205
Incentivos para atraer y retener personal de salud de zonas rurales del Perú: un estudio cualitativo
Huicho, Luis; Canseco, Francisco Díez; Lema, Claudia; Miranda, J. Jaime; Lescano, Andrés G.
2014-01-01
El objetivo fue identificar incentivos de atracción y retención en zonas rurales y distantes de Ayacucho, Perú. Fueron realizadas entrevistas en profundidad con 80 médicos, enfermeras, obstetras y técnicos (20 por grupo) de las zonas más pobres y con 11 funcionarios. No existen políticas sistemáticas de atracción y retención de personal de salud en Ayacucho. Los principales incentivos, en orden de importancia, fueron mejoras salariales, oportunidades de formación y capacitación, estabilidad laboral y nombramiento, mejoras en infraestructura y equipos, e incremento del personal. Se mencionaron también mejoras en la vivienda y alimentación, mayor cercanía con la familia y reconocimiento por el sistema de salud. Existen coincidencias y singularidades entre los distintos grupos sobre los incentivos clave para estimular el trabajo rural, que deben considerarse al diseñar políticas públicas. Las iniciativas del Estado deben comprender procesos rigurosos de monitoreo y evaluación, para asegurar que las mismas tengan el impacto deseado. PMID:22488318
Transmission scenarios of major vector-borne diseases in Colombia, 1990-2016.
Padilla, Julio César; Lizarazo, Fredy Eberto; Murillo, Olga Lucía; Mendigaña, Fernando Antonio; Pachón, Edwin; Vera, Mauricio Javier
2017-03-29
Introducción. Las enfermedades transmitidas por vectores representan más de 17 % de todas las enfermedades infecciosas y causan anualmente un millón de defunciones a nivel mundial. En Colombia, la malaria, el dengue, la enfermedad de Chagas y las leishmaniasis son condiciones endemoepidémicas persistentes.Objetivo. Determinar el comportamiento epidemiológico de las enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016.Materiales y métodos. Se hizo un estudio descriptivo del comportamiento epidemiológico de las principales enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016, con la información proveniente de fuentes oficiales secundarias.Resultados. En el periodo estudiado se registraron 5'360.134 casos de enfermedades transmitidas por vectores, de los cuales 54,7 % fueron de malaria y 24,9 % de dengue. Estos casos concentraron el 80 % de la carga acumulada de casos de enfermedades transmitidas por vectores. Las medianas de las tasas de incidencia fueron 1.371 y 188 por 100.00 habitantes para malaria y dengue, respectivamente. Además, los casos de chikungunya fueron 774.831 desde su introducción en el 2014 y, los de Zika, 117.674 desde su aparición en 2015. En las zonas rurales predominaron las enfermedades parasitarias transmitidas por vectores como la malaria, las leishmaniasis y la enfermedad de Chagas. A nivel urbano, predominaron el dengue, el chikungunya y el Zika.Conclusiones. La transmisión en Colombia de estas enfermedades es persistente en las zonas urbanas y en las rurales, y de tipo endemoepidémico en los casos de malaria, dengue, leishmaniasis y enfermedad de Chagas. Dicha transmisión se ha dado de manera focalizada y con patrones variables de intensidad. Asimismo, se mantienen las condiciones que han favorecido la transmisión emergente de nuevas arbovirosis.
Unidades del paisaje de Puerto Rico: la influencia del clima, el substrato y la topografia
William Gould; Michael E. Jimenez; Gary Potts; Maya Quinones; Sebastian Martinuzzi
2008-01-01
El mapa de unidades del paisaje de Puerto Rico representa variaciones climaticas, topograficas y del substrato mediante la integracion de seis zonas climaticas (Ewel y Whitmore, 1973), seis substratos (Bawiec, 2001; USGS, 2005), cinco posiciones topograficas, o topoformas (Martinuzzi et al. 2007), y cuerpos de agua (USGS 2005). Los substratos representan el conjunto...
Herrera-Ballesteros, Victor H; Castro, Franz; Gómez, Beatriz
2018-04-27
Caracterizar el gasto de bolsillo privado en medicamentos en función de los determinantes sociodemográficos y socioeconómicos. MATERIALES Y MéTODOS: La fuente de datos es la Encuesta de Gasto de Bolsillo en Medicamentos de 2014. Se caracterizó el gasto de bolsillo privado mediante variables explicativas sociodemográficas (SOD) y socioeconómicas (SES). Se hizo análisis factorial por componentes principales, regresión logística y lineal simple. Los Odds Ratio demuestran que la educación y la zona geográfica son determinantes fundamentales que inciden en el gasto de bolsillo. Los medicamentos son productos necesarios, en adición a que el gasto de bolsillo aumenta a un promedio del 2% por cada año de vida cronológica adicional. Existe mayor vulnerabilidad en las zonas más pauperizadas respecto del acceso a medicamentos, en especial en las indígenas e implica un mayor riesgo de gasto catastrófico a menor ingreso ante la mayor prevalencia de enfermedades crónicas. Copyright © 2018. Published by Elsevier Inc.
Capital social de los padres de escolares de una zona vulnerable.
Cornejo, Susana; Herrera, Ariel; Hilas, Elena; Gigena, Y Pablo
2018-01-01
El capital social supone importantes inversiones materiales, simbólicas y de esfuerzos. Conocer el capital social de una comunidad puede facilitar la comprensión del beneficio de las relaciones comunitarias para la promoción de salud. Con el objetivo de reconocer los componentes del capital social de padres de escolares atendiendo una escuela en una zona vulnerable de la ciudad de Córdoba, Argentina, indagamos a través de grupos focales acerca de elementos esenciales del capital social. La asintonía socio-cultural entre los pobladores originarios y los reubicados, la estigmatización policial y el clientelismo político han generado desconfianza del uno hacia el otro en diferentes aspectos convivenciales, siendo la familia la única red de apoyo. La escuela se reconoce como espacio adonde la gente espontáneamente se organiza para invertir en redes sociales, presentándose así con potencialidad para la promoción de conductas saludables, por el lugar simbólico que ocupa para los padres.
76 FR 58562 - Additional Designations, Foreign Narcotics Kingpin Designation Act
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-21
... controlled by significant foreign narcotics traffickers as identified by the President. In addition, the..., Jalisco, Mexico; Plaza Del Sol Local 28, Zona R, Guadalajara, Jalisco, Mexico; Paseo Del Heliotropo 3426, Monraz, Guadalajara, Jalisco, Mexico; DOB 09 Aug 1955; POB Jalisco, Mexico; Citizen Mexico; Nationality...
Fotometría superficial de la galaxia irregular NGC 1427A
NASA Astrophysics Data System (ADS)
Cellone, S. A.; Forte, J. C.
Se presenta fotometría superficial multicolor de la galaxia irregular NGC 1427A. Esta galaxia, un miembro del Cúmulo de Fornax que no ha sido estudiado previamente, muestra una morfología muy particular: una distribución estelar subyacente de bajo brillo superficial (LSB) con varias manchas brillantes dispuestas en una estructura anular deformada. Por sus colores muy azules se infiere que estas son zonas de formación estelar reciente. Al norte del cuerpo principal de la galaxia, y conectado con éste mediante filamentos LSB, hay un objeto de isofotas aproximadamente circulares. Este objeto tiene en sí mismo algunas zonas brillantes, pero su población estelar subyacente es significativamente más azul que la del cuerpo principal de la galaxia. Esto indica que ambos objetos han tenido distintas historias evolutivas. Estructuralmente, el objeto del norte es muy similar a algunas de las galaxias elípticas enanas más débiles que pueblan el Cúmulo de Fornax. Se discute la posible relación entre este objeto y la galaxia en si.
Las marismas costeras proporcionan numerosos beneficios a los ecosistemas, incluyendo la proporción del hábitat de la flora y fauna, la protección de las zonas costeras contra inundaciones durante eventos extremos, mejoran la calidad del agua para las almejas y ostras a través de...
¿Qué está haciendo la EPA para proteger a los arrecifes de coral?
La EPA protege a los arrecifes de coral mediante la implementación de programas de la Ley de Agua Limpia que protegen la calidad del agua en cuencas y zonas costeras de las áreas con arrecifes de coral.
ERIC Educational Resources Information Center
Lopez, Maria I. Hernandez; And Others
In 1962 and again in 1965, a group of sixth and ninth grade students in selected schools in four Puerto Rican communities were interviewed to investigate the factors influencing students' decision to withdraw from school before completing twelfth grade and to identify some characteristics of dropouts. Of 616 students interviewed in 1962, 20.9% of…
Seizures, cysticercosis and rural-to-urban migration: the PERU MIGRANT study
Gonzales, Isidro; Miranda, J Jaime; Rodriguez, Silvia; Vargas, Victor; Cjuno, Alfredo; Smeeth, Liam; Gonzalez, Armando E; Tsang, Victor C W; Gilman, Robert H; Garcia, Hector H
2015-01-01
Objectives To examine the prevalence of seizures, epilepsy and seropositivity to cysticercosis in rural villagers (cysticercosis-endemic setting), rural-to-urban migrants into a non-endemic urban shanty town and urban inhabitants of the same non-endemic shanty town. Methods Three Peruvian populations (n = 985) originally recruited into a study about chronic diseases and migration were studied. These groups included rural inhabitants from an endemic region (n = 200), long-term rural-to-urban migrants (n = 589) and individuals living in the same urban setting (n = 196). Seizure disorders were detected by a survey, and a neurologist examined positive respondents. Serum samples from 981/985 individuals were processed for cysticercosis antibodies on immunoblot. Results Epilepsy prevalence (per 1000 people) was 15.3 in the urban group, 35.6 in migrants and 25 in rural inhabitants. A gradient in cysticercosis antibody seroprevalence was observed: urban 2%, migrant 13.5% and rural group 18% (P < 0.05). A similarly increasing pattern of higher seroprevalence was observed among migrants by age at migration. In rural villagers, there was strong evidence of an association between positive serology and having seizures (P = 0.011) but such an association was not observed in long-term migrants or in urban residents. In the entire study population, compared with seronegative participants, those with strong antibody reactions (≥ 4 antibody bands) were more likely to have epilepsy (P < 0.001). Conclusions It is not only international migration that affects cysticercosis endemicity; internal migration can also affect patterns of endemicity within an endemic country. The neurological consequences of cysticercosis infection likely outlast the antibody response for years after rural-to-urban migration. Objectifs Examiner la prévalence des crises d’épilepsie, de l’épilepsie et de la séropositivité à la cysticercose chez les villageois des zones rurales (cadre endémique pour la cysticercose), chez les migrants des zones ruraux vers les zones urbaines dans un bidonville urbain non endémique et chez les habitants urbains du même bidonville non endémique. Méthodes Trois populations péruviennes (n = 985) recrutées initialement dans une étude sur les maladies chroniques et la migration, ont été étudiées. Ces groupes comprenaient des habitants de zones rurales d'une région d'endémie (n = 200), des migrants de long terme de zones ruraux vers les villes (n = 589) et les personnes vivant dans le même milieu urbain (n = 196). Les troubles épileptiques ont été détectés par un sondage et un neurologue a examiné les répondants positifs. Des échantillons de sérum de 981/985 individus ont été testés pour les anticorps de cysticercose par Immunoblot. Résultats La prévalence de l’épilepsie (pour 1000 personnes) était de 15,3 dans le groupe urbain; 35,6 chez les migrants et 25 dans la population rurale. Un gradient dans la séroprévalence des anticorps de la cysticercose a été observé: dans le groupe urbain 2%, le groupe de migrants 13,5% et le groupe rural 18% (p <0,05). Une tendance croissante similaire de séroprévalence plus élevée a été observée chez les migrants selon l’âge à la migration. Chez les villageois ruraux, il y avait des preuves solides d'une association entre une sérologie positive et le fait d'avoir des crises (p = 0,011), mais une telle association n'a pas été observée chez les migrants de long terme ou chez les résidents urbains. Dans l'ensemble de la population de l’étude, ceux avec de fortes réactions d'anticorps (≥ 4 bandes d'anticorps) étaient plus susceptibles d'avoir l’épilepsie (p <0,001) comparé aux participants séronégatifs. Conclusions La migration internationale n'est pas la seule qui affecte l'endémicité de la cysticercose; la migration interne peut aussi modifier les profils d'endémicité au sein d'un même pays d'endémie. Les conséquences neurologiques de l'infection par la cysticercose sont susceptibles de survivre à la réponse d'anticorps durant des années après la migration des zones rurales vers les zones urbaines. Objetivos Examinar la prevalencia de convulsiones, epilepsia, y seropositividad para cisticercosis entre población rural (de zonas endémicas para cisticercosis), inmigrantes provenientes de zonas rurales a tugurios urbanos no endémicos, y habitantes urbanos de los mismo tugurios urbanos no endémicos. Métodos Se estudiaron tres poblaciones peruanas (n=985) originalmente reclutadas en un estudio de enfermedades crónicas y migración. Estos grupos incluían habitantes rurales de una región endémica (n=200), inmigrantes de larga duración de zonas rurales a urbanas (n=589), e individuos que vivían en la misma zona urbana (n=196). Las convulsiones se detectaron mediante una encuesta y un neurólogo examinó a quienes habían respondido positivamente. Se procesaron muestras de suero de 981/985 individuos en busca de anticuerpos para cisticercosis mediante inmunoblot. Resultados La prevalencia de epilepsia (por 1,000 personas) era de 15.3 en el grupo urbano, 35.6 en inmigrantes y 25 en habitantes rurales. Se observó un gradiente en la seroprevalencia de los anticuerpos para cisticercosis: grupos urbano 2%, inmigrante 13.5% y rural 18% (p<0.05). Se observó un patrón de aumento similar de mayor seroprevalencia entre inmigrantes según la edad que tenían en el momento de emigrar. En pobladores rurales, había una evidencia importante de asociación entre tener una serología positiva y sufrir convulsiones (p=0.011), pero esta asociación no se observaba en inmigrantes de larga duración o residentes urbanos. En la población al completo, comparada con los participantes seronegativos, aquellos con una fuerte reactividad de anticuerpos (≥4 bandas de anticuerpos) tenían una mayor probabilidad de sufrir epilepsia (p<0.001). Conclusiones No solo la migración internacional afecta la endemicidad de cisticercosis; la migración interna también puede afectar los patrones de endemicidad dentro de un país endémico. Las consecuencias neurológicas de la infección por cisticercos podrían durar más que la respuesta a anticuerpos años después de la migración de zonas rurales a zonas urbanas. PMID:25581851
MÉXICO Y ESTADO DE GUANAJUATO: TRANSFERENCIAS INTERGENERACIONALES HACIA LOS ADULTOS MAYORES*
Montes de Oca, Verónica; Hebrero, Mirna
2017-01-01
RESUMEN En México, las transferencias formales e informales destinadas al apoyo de las personas adultas mayores son diversificadas. En este documento se analizan la tendencia nacional y los resultados de un estudio centrado en la entidad federativa de Guanajuato. La distribución de los apoyos confirma que las transferencias hechas por el sistema de seguridad social tienen un sesgo urbano y que las transferencias formales del gobierno federal se orientan a las áreas menos urbanizadas, particularmente las zonas rurales. A pesar de las transferencias formales (esporádicas e insuficientes), las necesidades económicas y de salud de las personas mayores persisten y ello lleva a que sus familiares realicen transferencias informales de naturaleza ascendente. En México —y más concretamente en Guanajuato— el apoyo de quienes residen con la persona mayor tiene un significativo peso, y lo contrario sucede con el de quienes han migrado. A partir de este material, se analiza el rol que, de acuerdo a su cohorte y su condición migratoria, desempeñan los descendientes. En todo caso, queda de manifiesto que, en cada entidad nacional, las dinámicas de transferencias intergeneracionales son de diversos tipos. PMID:29375179
Alves, Maria de Fátima Paz
2003-01-01
This study analyzes the concepts displayed by rural men in the Zona da Mata region in the State of Pernambuco, Brazil, concerning their sexual practices and STD/AIDS prevention. The study adopts a qualitative methodology, having interviewed 22 men According to the interviews, their first sexual intercourse is characterized as a learning experience and is sometimes marked by violence. They make a distinction between the "woman at home" and "street women"; they acknowledge women's sexual desire and value reciprocity in sexual relations, differentiating between the kinds of sex they have with different categories of women. Seven men report homoerotic experiences during adolescence, which they ascribe to immaturity, not affecting their heterosexual identity. Condom use, perceived in a negative light, is inconstant and irregular, inversely proportional to knowing the female partner. STDs in general inspire little fear, while AIDS is associated with death; the interviewees do not see themselves at risk of acquiring HIV. Ambiguities in the men's discourse, together with a basically ineffective approach by health services and preventive campaigns, reveal a high level of exposure to the risk of contracting STDs/AIDS among the interviewees and their female or male partners.
Descripción de la zona de alta difusión en un modelo bidimensional para hojas de corriente
NASA Astrophysics Data System (ADS)
Montero, M. F.; Paola, C. A.; Platzeck, A. M.
Los modelos bidimensionales para describir hojas de corriente de alta simetría no suministran una descripción detallada de las regiones donde la difusión es considerablemente importante. Tal es el caso de los modelos desarrollados en la década del '60 por Sweet, Parker, Petschek y Sonnerup. En esta comunicación presentamos una solución de las ecuaciones MHD en el entorno del origen, construyendo series bidimensionales para todas las magnitudes físicas involucradas. Valiéndonos de la alta simetría y de las características del problema, logramos reducir el número de coeficientes a calcular. Utilizamos un programa autoconsistente para extender el cálculo a regiones vecinas con difusión moderada o despreciable.
Trabajo Social en la Micro y Macro Práctica en el Contexto de la Tuberculosis
Moya, Eva M.; Chavez-Baray, Silvia M.; Martínez, Omar
2017-01-01
Resumen El estudio de la problemática relacionada con la infección de tuberculosis (TB) en la frontera México-Estadounidense implica la consideración de tres aspectos complejos y entrelazados: la TB, una entidad patológica que debido a sus características epidemiológicas y patogénicas, resulta difícil de seguir y atender de manera completa; la zona fronteriza, zona geográfica y epidemiológica que entrelaza dos naciones, dos culturas, dos sistemas de salud y leyes diferentes; además del estigma, que implica más que tratamientos clínicos y abordajes de categorías de riesgo debido a la condición social y bajo conocimiento. Este trabajo narra diez estrategias realizadas en México y la frontera México-Estadounidense del año 2006 al 2013 como un esfuerzo de ampliar la comprensión de este fenómeno social y de salud pública conformado por una infección, un entorno físico y personas, también de la identificación y aplicación de prácticas competentes de abogacía y movilización social. Los trabajos realizados y presentados dan a conocer diferentes intervenciones para generar adherencia al tratamiento, mitigar el estigma relacionado con la infección de TB, mejorar la atención centrada en la persona e informar la relevancia del abordaje micro y macro de la salud y el trabajador social. PMID:29503982
Digitalización de diapositivas del Sol en H α
NASA Astrophysics Data System (ADS)
Missio, H.; Montenegro, C.; Montenegro, R.
El objetivo de este trabajo ha sido el de obtener imágenes digitalizadas de las diapositivas tomadas del Sol en luz de hidrógeno de la línea correspondiente a Hα, y de esta manera llegar a convertir las mismas a un archivo digital para poder ser tratadas luego por computadora y poder contabilizar con exactitud, mediante un programa adecuado para tal fin, las zonas activas del Sol en la imagen digitalizada. En principio, para llegar a esto se pensó en la utilización de medios accesibles, y como detector se utilizó un fototransistor ubicado dentro de un soporte rectangular sobre dos ejes de desplazamiento X e Y. Se han obtenido con este procedimiento imágenes de buena calidad, construídas a partir de tres datos digitalizados en cada barrido que aportan la posición X e Y y la intensidad del pixel en ese punto indicada en 255 tonos de grises.
Historia Verdadera del Chicano del Norte. [True History of the Chicano of the North].
ERIC Educational Resources Information Center
Herrera, David; Bryan, Clifford E.
Very little is known about the Chicanos in the northern U.S., especially those in the Northwest. Research and writing on Chicanos have concentrated on the Southwest or large urban settings, thus excluding those Chicanos residing in rural settings except for those in the migrant stream. These rural residents have become a forgotten people,…
Inverse modeling of groundwater flow in the semiarid evaporitic closed basin of Los Monegros, Spain
NASA Astrophysics Data System (ADS)
Samper-Calvete, F. J.; García-Vera, M. A.
Only minor attention has been given in the past to the study of closed-basin hydrogeology in evaporitic environments, because these basins usually contain poor-quality groundwater. The motivation for hydrogeological research in the Los Monegros area in northeastern Spain was the approval in 1986 of a large irrigation project in the Ebre River basin. The irrigation of 60,000 ha is planned, partly in an evaporitic closed basin containing playa lakes. The project has given rise to environmental concerns. The evaluation of the hydrologic impacts of irrigation requires quantifying properly the hydrogeology of the area. With the available information, a conceptual hydrogeological model was formulated that identifies two main aquifers connected through a leaky aquitard. On the basis of the conceptual model, a numerical model was calibrated under steady-state conditions using the method of maximum-likelihood automatic parameter estimation (Carrera and Neuman, 1986a). The calibrated model reproduces the measured hydraulic heads fairly well and is consistent with independent information on groundwater discharge. By the solution of the inverse problem, reliable parameter estimates were obtained. It is concluded that anisotropy plays a major role in some parts of the lower aquifer. The geometric average of model conductivity is almost two orders of magnitude larger than the average conductivity derived from small-scale field tests. This scale effect in hydraulic conductivity is consistent with the findings of Neuman (1994) and Sánchez-Vila et al. (1996). Résumé Dans le passé, on s'est peu intéresséà l'hydrogéologie des bassins fermés en milieu évaporitique, parce que ces bassins possèdent en général de l'eau souterraine de qualité médiocre. L'intérêt porté aux recherches hydrogéologiques dans la région de Los Monegros, dans le nord-est de l'Espagne est dûà l'approbation en 1986 d'un vaste projet d'irrigation dans le bassin de l'Ebre. L'irrigation de 60000 ha a été programmée, en partie dans un bassin évaporitique fermé où existent des lacs de playa. Le projet a fait émergé des préoccupations environnementales. L'évaluation des impacts hydrologiques de l'irrigation implique de quantifier correctement l'hydrogéologie de cette région. A partir des informations disponibles, un modèle hydrogéologique conceptuel a étéétabli il identifie deux aquifères principaux interconnectés par drainance au travers d'un imperméable. Un modèle numérique, établi sur la base de ce modèle conceptuel, a été calibré en conditions de régime permanent, en utilisant la méthode d'estimation automatique du maximum de vraisemblance des paramètres (Carrera and Neuman, 1986a). Le modèle calibré reproduit correctement la piézométrie mesurée et est en accord avec les informations concernant l'écoulement des nappes. La résolution du problème inverse a fourni des estimations acceptables des paramètres. On en a conclu que l'anisotropie joue un rôle essentiel dans certaines parties de l'aquifère inférieur. La moyenne géométrique de la conductivité hydraulique est d'environ deux ordres de grandeur plus élevée que la conductivité hydraulique moyenne obtenue par des essais de terrain à l'échelle locale. Cet effet d'échelle sur la conductivité hydraulique est conforme aux résultats obtenus par Neuman (1994) et Sánchez-Vila et al. (1996). Resumen La hidrogeología de zonas endorreicas en zonas evaporíticas ha recibido muy poca atención en el pasado debido fundamentalmente a que en estas zonas las aguas subterráneas tienen una elevada salinidad debido a la alta solubilidad de sus materiales. El interés por la hidrogeología de la zona de Los Monegros en el noreste de España surgió a raiz de la aprobación en 1986 del proyecto de Los Monegros II en la zona central del valle del Ebro que contempla la puesta en regadío de 60,000 ha, algunas de las cuales se encuentran situadas en la zona endorreica de Los Monegros en la que existen toda una serie de lagunas salinas. La implantación del regadío en esta zona puede alterar el régimen hidrológico de las lagunas, provocar problemas de salinización de suelos y aguas y aumentar la salinidad del río Ebro. Con el fin de evaluar estos efectos se construyó un modelo numérico del flujo subterráneo. Con la información disponible se pueden distinguir dos acuíferos que están conectados mediante un acuitardo. El modelo de flujo se calibró en régimen estacionario utilizando el procedimiento de calibración automática de Carrera y Neuman (1986a) basado en el método de la máxima verosimilitud. El modelo finalmente calibrado es capaz de reproducir los niveles piezométricos medidos y es coherente con los resultados de los balances hidrológicos en las lagunas. La conductividad hidráulica media del modelo es superior en casi dos órdenes de magnitud a la media de las conductividades hidráulicas obtenidas en ensayos de campo a escala local. Este efecto de escala en la conductividad hidráulica es coherente con los resultados de Neuman (1994) y Sánchez-Vila et al. (1996) y confirma que dicho efecto también se observa en medios evaporíticos.
ERIC Educational Resources Information Center
Peairson, Shannon; Austin, Ann M. Berghout; de Aquino, Cyle Nielsen; de Burro, Elizabeth Urbieta
2008-01-01
Participants included 106 infants and toddlers living in rural Paraguay and their primary caregiver. Children ranged in age from birth to 24 months and belonged to two distinct groups, including 46 children who had never participated in Pastoral del Nino, an early child development program, and 60 children who had participated in Pastoral for at…
Pastoral del Nino: Bringing the Abundant Life to Paraguayan Children
ERIC Educational Resources Information Center
Austin, Ann Berghout; Aquino, Cyle; Burro, Elizabeth
2007-01-01
Pastoral del Nino is transforming children's lives in rural Paraguay. Part of Pastoral Social (Catholic Social Services), Pastoral del Nino's primary focus is to bring "vida en abundancia" (the abundant life) to families by ensuring that mothers survive childbirth and children reach their first birthdays. In addition, the organization…
The Foreign Policy of Venezuela Toward El Salvador: 1979-1983
1990-06-01
vista extra-regional, la "zona vital" es rica en materiales estrat~gicos, tales como el petr6leo, el hierro, y el aluminlo. Adem~s del petr6leo de...nivel de post-grado, en el Area de hidrocarburos para el periodo 1981 / 1982. Ofrecimiento de cooperaci6n en el campo de geologia de uranlo y materiales ...hombre, yo lo conocia, aparte de que era un homnbre muy preparado, muy inteligente , era un fan~tico. *Un fanatico religioso. Yo s6 porque lo digo
1986-08-01
Iuz y clorofila; conl posible opcibn a determinar metales pesados en sedimentos, en el Estrecho de Gibral- tar y zonas adyacentes. Todo ello muy...Estrecho. El trabajo de campo acabara& en Abril y se podra’ disponer de un informe pr-eli- minar par-a despue’s del Verano. Este programa ha sido...pademas realizar una primera campar~a en Junio de 1985 la usari’amas coma campa de pruebas . Aparte de esta campah’a pensamos realizar otra en Octubre a
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jimenez, T.; Olson, K.
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.
ERIC Educational Resources Information Center
Vejarano, Gilberto M.; And Others
This booklet presents the ideas that came out of the Regional Meeting for Adult Literacy and Rural Development. The meeting took place in September 1981 at the Regional Center for Adult Education and Functional Literacy for Latin America (CREFAL) in Mexico. Basically, a discussion of adult literacy in the rural areas of Latin America is presented.…
Instructivo del Alfabetizador: Poblacion Rural (Reading and Writing Instruction: Rural Population).
ERIC Educational Resources Information Center
Instituto Nacional para la Educacion de los Adultos, Mexico City (Mexico).
This Mexican series of instructional materials is designed for Spanish speaking adults who are in the process of becoming literate or have recently become literate in their native language. The reading/writing workbook is presented in two volumes along with a teacher's manual for an adult literacy program directed at rural inhabitants of Mexico.…
Estudio polarimétrico de NGC 104 (47 Tucanae)
NASA Astrophysics Data System (ADS)
Forte, J. C.; Bassino, L. P.; Vega, E. I.; Cellone, S.; Pellizza, L.; Méndez, M.
Se presentan observaciones polarimétricas en el Visual y sin filtro para 72 estrellas, 14 zonas de referencia y el núcleo del cúmulo globular NGC 104. Las medidas, hechas en el CASLEO con el nuevo polarimétro CASPROF, muestran un comportamiento complejo que incluye: a) dos componentes de polarización a lo largo de la visual; b) signos de envolturas polvorientas en 8 de 10 estrellas variables de largo período pertenecientes al cúmulo c) media docena de estrellas con alta polarización residual (P> 0.20 %) originada probablemente en scattering. Estas estrellas se encuentran próximas a una estructura extendida, coincidente con la región central del cúmulo, detectada en observaciones IRAS. Las observaciones son consistentes con la presencia de pequeñas cantidades de polvo originada en procesos de pérdida de masa.
Transfer of bovine demi-embryos with and without the zona pellucida.
Warfield, S J; Seidel, G E; Elsden, R P
1987-09-01
Bisected bovine embryos with or without the zona pellucida were transferred to recipients nonsurgically in five field trials. Embryos were collected from superovulated donors 6.5 to 7.5 d after estrus; only embryos of good and excellent quality were bisected. Demi-embryos were transferred either within a zona pellucida, without a zona pellucida, without a zona pellucida, or in the third and fourth trials, without a zona but embedded in 7% gelatin. Pregnancies were diagnosed at 44 to 68 d of gestation. In a preliminary trial, 9/29 zona pellucida-intact demi-embryos developed into fetuses compared with 1/10 zona pellucida-free demi-embryos (P greater than .1). The proportion of zona-free demi-embryos developing to fetuses was not significantly different from the zona-intact group in the second trial either, 24/49 and 5/19, respectively. In trial 3, the proportion of zona pellucida-free demi-embryos developing was 8/25; of zona-enclosed embryos, 29/88; and of zona-free demi-embryos embedded in gelatin, 8/22 (P greater than .1). Similarly, in the fourth trial the rate of development of zona-free demi-embryos to fetuses was 5/12, that of zona-enclosed embryos was 32/81, and that of zona-free demi-embryos embedded in gelatin was 3/12 (P greater than .1). In trial 5, survival of zona-enclosed demi-embryos to fetuses was 40/105, and of zona-free demi-embryos, 46/109 (P greater than .1). Except for trial 2, half of the demi-embryos were twinned, one to each uterine horn; twinning did not significantly affect the proportion developing to fetuses for any of the demi-embryo groups. It is concluded that placing post-compaction demi-embryos into the zona pellucida for transfer does not improve pregnancy rates significantly.
Buckler, Denny; Stefanov, Jim
2004-01-01
La region fronteriza de los Estados Unidos y Mexico abarca una gran diversidad de ambientes fisicos y habitaciones, entre los cuales estan los humedales, desiertos, pastos, montanas, y bosques. Estos a su vez son unicos en cuanto a su diversidad de recursos acuaticos minerales, y biologicos. La region se interconecta economica, politica, y socialmente debido a su herencia binacional. En 1995, cerca de 11 millones de habitantes vivian en la zona adyacente a la frontera. Un estudio sugiere que esa poblacion podria doblarse antes del ano 2020.
El uso de la neuromodulación para el tratamiento del temblor
Bendersky, Damián; Ajler, Pablo; Yampolsky, Claudio
2014-01-01
Introducción: El temblor puede ser un desorden incapacitante y el tratamiento de primera línea para estos pacientes es farmacológico. Sin embargo, este tratamiento puede llevar a una reducción satisfactoria del temblor en sólo el 50% de los pacientes con temblor esencial. La talamotomía era el tratamiento de elección para el temblor refractario al tratamiento médico hasta que comenzó a utilizarse la estimulación cerebral profunda (ECP) del núcleo ventral intermedio (Vim) del tálamo. En la actualidad, raramente se realiza la talamotomía. Métodos: Este artículo es una revisión no sistemática de las indicaciones, resultados, parámetros de programación y técnica quirúrgica de la ECP del Vim para el tratamiento del temblor. Resultados: Aunque los resultados clínicos son similares usando la talamotomía o la ECP del Vim, la primera causa más efectos adversos que la última. Además, la ECP puede ser usada bilateralmente, mientras que la talamotomía tiene un alto riesgo de causar disartria cuando se realiza de ambos lados. La ECP del Vim logró una adecuada mejoría del temblor en varias series de pacientes con temblor causado por temblor esencial, enfermedad de Parkinson o esclerosis múltiple. Además del Vim, hay otros blancos que están siendo usados por varios autores, tales como la zona incerta y las radiaciones prelemniscales. Conclusión: La ECP del Vim es un tratamiento útil para el temblor incapacitante refractario al tratamiento médico. Es esencial realizar una precisa selección de pacientes, así como utilizar una técnica quirúrgica correcta. Aún se desconoce el mejor blanco estereotáctico para el temblor, aunque el Vim es el más usado. PMID:25165613
Schimmel, Tim; Cohen, Jacques; Saunders, Helen; Alikani, Mina
2014-12-01
Does laser-assisted zona thinning of cleavage stage mouse embryos facilitate hatching in vitro? No, unlike laser zona opening, zona thinning does not facilitate embryo hatching. Artificial opening of the zona pellucida facilitates hatching of mouse and human embryos. Laser-assisted zona thinning has also been used for the purpose of assisted hatching of human embryos but it has not been properly investigated in an animal model; thinning methods have produced inconsistent clinical results. Time-lapse microscopy was used to study the hatching process in the mouse after zona opening and zona thinning; a control group of embryos was not zona-manipulated but exposed to the same laser energy. Eight-cell CB6F1/J mouse embryos were pooled and allocated to three groups (n = 56 per group): A control group of embryos that were exposed to a dose of laser energy focused outside the zona pellucida (zona intact); one experimental group of embryos in which the zona pellucida was opened by complete ablation using the same total number of pulses as the control group; a second experimental group of embryos in which the zona pellucida was thinned to establish a smooth lased area using the same number of pulses as used in the other two groups. The width of the zona opening was 25 μm and width of the thinned area was 35 μm. Development was monitored by time-lapse microscopy. Overall treatment differences for continuous variables were analyzed by analysis of variance and pairwise comparisons using the Student t-test allowing for unequal variances, while for categorical data, a standard chi-squared test was utilized for all pairwise comparisons. The frequency of complete hatching was 33.9% in the control group, 94.4% after zona opening, and 39.3% after zona thinning (overall group comparison, P < 0.0001). Overall, 60.7% of the zona-thinned embryos did not complete the hatching process and remained trapped within the zona; when they did hatch, they did not necessarily hatch from the zona-thinned area. Hatching in about one-third of the zona-intact embryos began with breaches at multiple sites by small groups of cells. Likewise, 53.6% of zona-thinned embryos had multiple breaches, always involving an area outside the thinned zone. Zona opening decreased multiple breaching and led to blastocyst escape an average of 14 h earlier than zona-thinned embryos and 5.5 h before control embryos (P = 0.0003). The experiments presented here were limited to in vitro experiments performed in the mouse. Whether human embryos would behave the same way under similar circumstances is unknown. We postulate that zona thinning is not beneficial in human embryos. The experiments demonstrate that zona thinning is not equivalent to zona opening for assisted hatching. The study provides reason for systematic reviews of assisted hatching trials to take the method of assisted hatching into consideration and not combine the results of zona thinning and zona opening procedures. Institutional funds were used for the study. No competing interests are declared. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.
NASA Astrophysics Data System (ADS)
Cintron Aponte, Rommel
La tecnica de Nakamura ha sido utilizada a nivel mundial para determinar periodos fundamentales del suelo. La tecnica consiste en calcular y graficar cocientes espectrales H/V de vibraciones ambientales registradas sobre el suelo. Mediciones de vibraciones ambientales fueron tomadas en 151 lugares dentro del municipio de Humacao, localizado al este de Puerto Rico. Los datos se procesaron utilizando espectros de Fourier y espectros de potencia. La tecnica fue validada al compararla con los resultados de cocientes espectrales H/V de registros de sismos debiles y tambien con una modelacion numerica realizada con datos de un ensayo "downhole". Las graficas de los cocientes espectrales H/V fueron divididas en casos y grupos, los cuales dependen de la facilidad para identificar el periodo fundamental pico y amplitudes en frecuencias menores de 1 Hz, respectivamente. Los resultados obtenidos con ambos espectros fueron comparados y se concluye que los mismos se complementan para proveer resultados mas confiables. Se crearon mapas de periodos fundamentales, factores de amplitud, isoperiodos y clasificacion sismica de sitio. Los mapas de isoperiodos fueron realizados en las zonas mas pobladas sobre depositos de suelo. El mapa de periodos fundamentales del suelo mostro buena correlacion con la geologia local. El mapa de clasificacion sismica derivado de periodos de sitio fue comparado con el mapa de clasificacion sismica derivado de barrenos geotecnicos. El mapa de clasificacion obtenido de periodos puede sobreestimar un poco algunas clasificaciones del suelo. Sin embargo, este mapa puede proveer un estimado aproximado de la velocidad de onda de corte promedio del suelo hasta una profundidad de 100 pies (30 metros).
ERIC Educational Resources Information Center
de Schutter, Anton
In participatory research, education and learner participation are directly connected. The document analyzes the role of a participatory research method in the basic education of rural adults. The different phases of the Participant Research method are presented, along with a profound analysis of both research and participation. The claim is that…
78 FR 30268 - Del Norte County Resource Advisory Committee
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-22
... Schools and Community Self-Determination Act (Pub. L. 112-141) (the Act) and operates in compliance with... to review prior year project's progress. Should the Secure Rural Schools Act be reauthorized, the.... ADDRESSES: The meetings will be held at the Del Norte County Unified School District, Redwood Room, 301 West...
ERIC Educational Resources Information Center
Finegold, Lynda
A major stumbling block for the implementation of Mexico's Global Development Plan has been the country's large rural population of Indians. One government strategy to integrate this sector into the mainstream of society has been to teach Spanish, the official language, as a second language, while at the same time fostering ethnic pride. The…
Los plaguicidas y la contaminacion del medio ambiente Venezolano
Stickel, L.F.; Stickel, W.H.
1972-01-01
RESUMEN DE RECOMENDACIONES Recomendaciones para el Programa de Investigacion: 1. Establecer un sistema de muestreo biologico para detectar los niveles tendencias de los productos quimicos toxicos en un peque?o numero de si tios representativos. 2. Mantener continua vigilancia de la contaminacion ambiental, mediante la seleccion acertadamente dirigida de las zonas afectadas y de las fuentes de contaminacion. 3. Realizar estudios acerca de las poblaciones de animales silvestres, y del exito de los procesos reproductivos de las especies o grupos clayes de animales que se consideran mas gravemente afectados. 4. Preparar recomendaciones para una accion gubernamental de proteccion al hombre, a la fauna silvestre y al medio ambiente. Recomendaciones para la Accion Administrativa: 1. Establecer limites a la tolerancia de los residuos de plaguicidas en los alimentos. Constituye una medida clave para disminuir la contaminacion ambiental. 2. Establecer normas de calidad del agua para las corrientes, represas, la gos y otros cuerpos. Es la segunda medida clave para reducir la contaminacion del ambiente 3. Exigir un tratamiento adecuado de los efluentes industriales, especialmente antes de que se construyan las nuevas plantas. 4. Exigir a los agricultores que en el uso de plaguicidas sigan los consejos tecnicos autorizados y negar a los vendedores el derecho a recomendar productos por su cuenta. 5. Tomar medidas para recoger y eliminar los recipientes y sobrantes de los plaguicidas.
Capture-zone design in an aquifer influenced by cyclic fluctuations in hydraulic gradients
NASA Astrophysics Data System (ADS)
Zawadzki, Willy; Chorley, Don; Patrick, Guy
2002-10-01
Design of a groundwater pumping and treatment system for a wood-treatment facility adjacent to the tidally influenced Fraser River estuary required the development of methodologies to account for cyclic variations in hydraulic gradients. Design of such systems must consider the effects of these cyclic fluctuations on the capture of dissolved-phase contaminants. When the period of the cyclic fluctuation is much less than the travel time of the dissolved contaminant from the source to the discharge point, the hydraulic-gradient variations resulting from these cycles can be ignored. Capture zones are then designed based on the average hydraulic gradient determined using filter techniques on continuous groundwater-level measurements. When the period of cyclic fluctuation in hydraulic gradient is near to or greater than the contaminant travel time, the resulting hydraulic-gradient variations cannot be ignored. In these instances, procedures are developed to account for these fluctuations in the capture-zone design. These include proper characterization of the groundwater regime, assessment of the average travel time and period of the cyclic fluctuations, and numerical techniques which allow accounting for the cyclic fluctuations in the design of the capture zone. Résumé. L'étude d'un système de pompage et de traitement de l'eau souterraine d'une usine de traitement du bois proche de l'estuaire de la rivière Fraser, influencé par les marées, a nécessité la mise au point de méthodologies pour prendre en compte les variations cycliques de gradients hydrauliques. L'étude de tels systèmes doit considérer les effets de ces variations cycliques sur l'extraction des contaminants en phase dissoute. Lorsque la période des variations cycliques est très inférieure au temps de parcours du contaminant dissous entre la source et le point d'émergence, les variations du gradient hydraulique résultant de ces cycles peuvent être ignorées. Les zones d'extraction sont alors réalisées sur la base du gradient hydraulique moyen déterminé au moyen de techniques de filtrage sur des mesures continues de la piézométrie. Lorsque la période de la fluctuation cyclique dans le gradient hydraulique est proche de ou supérieure au temps de parcours du contaminant, les variations résultantes de gradient hydraulique ne peuvent plus être ignorées. Dans ces cas-là, des procédures ont été mises au point pour prendre en compte ces fluctuations dans la conception de la zone d'extraction. Celles-ci prennent en considération la caractérisation propre du régime de la nappe, l'évaluation du temps de parcours moyen et de la période des fluctuations cycliques, et des techniques numériques qui permettent de considérer les fluctuations cycliques dans la conception de la zone d'extraction. Resumen. El diseño de un sistema de bombeo y tratamiento de aguas subterráneas para una instalación de manufactura de madera que está próxima al estuario del río Fraser, sometido a la influencia de las mareas, ha requerido el desarrollo de metodologías para tener en cuenta las variaciones cíclicas de los gradientes hidráulicos. El diseño de tales sistemas debe considerar los efectos de las fluctuaciones cíclicas en la captura de contaminantes en fase disuelta. Cuando el período de la fluctuación cíclica es mucho menor que el tiempo de tránsito del contaminante disuelto entre el punto de entrada y el de descarga, se puede ignorar las variaciones del gradiente hidráulico provocadas por dichos ciclos. Las zonas de captura se diseñan entonces en función del gradiente hidráulico promedio, que se determina mediante técnicas de filtrado de medidas continuas del nivel piezométrico. Cuando el período de la fluctuación cíclica del gradiente hidráulico es comparable o mayor que el tiempo de tránsito del contaminante, no puede ignorarse las variaciones resultantes en el gradiente hidráulico. En ese caso, se tiene que desarrollar procedimientos para contar con las fluctuaciones en el diseño de las zonas de captura. Ello implica una adecuada caracterización del régimen de las aguas subterráneas, el establecimiento del tiempo de tránsito y del período de las fluctuaciones cíclicas, y el uso de técnicas numéricas que permitan incluirlas en el diseño de la zona de captura.
NASA Astrophysics Data System (ADS)
Nolan, Bernard T.; Campbell, David L.; Senterfit, Robert M.
A geophysical survey was conducted to determine the depth of the base of the water-table aquifer in the southern part of Jackson Hole, Wyoming, USA. Audio-magnetotellurics (AMT) measurements at 77 sites in the study area yielded electrical-resistivity logs of the subsurface, and these were used to infer lithologic changes with depth. A 100-600ohm-m geoelectric layer, designated the Jackson aquifer, was used to represent surficial saturated, unconsolidated deposits of Quaternary age. The median depth of the base of the Jackson aquifer is estimated to be 200ft (61m), based on 62 sites that had sufficient resistivity data. AMT-measured values were kriged to predict the depth to the base of the aquifer throughout the southern part of Jackson Hole. Contour maps of the kriging predictions indicate that the depth of the base of the Jackson aquifer is shallow in the central part of the study area near the East and West Gros Ventre Buttes, deeper in the west near the Teton fault system, and shallow at the southern edge of Jackson Hole. Predicted, contoured depths range from 100ft (30m) in the south, near the confluences of Spring Creek and Flat Creek with the Snake River, to 700ft (210m) in the west, near the town of Wilson, Wyoming. Résumé Une campagne géophysique a été entreprise pour préciser la profondeur du mur de l'aquifère dans le secteur sud de Jackson Hole (Wyoming, États-Unis). Des mesures audio-magnétotelluriques (audio MT) sur 77 sites de ce secteur ont fourni des logs de résistivitéélectrique du sous-sol ; les variations de la lithologie en fonction de la profondeur en ont été déduites. Un niveau géoélectrique à 100-600ohm.m, dénommé "aquifère de Jackson", a servi à définir des dépôts superficiels quaternaires saturés en eau et non consolidés. La profondeur médiane de la base de l'aquifère de Jackson est de l'ordre de 61m, à partir des 62 sites ayant fourni suffisamment de données de résistivité. Les valeurs audio MT mesurées ont été krigées afin d'estimer la profondeur de la base de la formation aquifère dans la partie sud de Jackson Hole. Les cartes d'isovaleurs d'estimation krigées indiquent que la profondeur de la base de la formation aquifère de Jackson est faible dans la partie centrale de la zone d'étude à l'est et à l'ouest des monts Gros Ventre, plus grande dans le secteur ouest près de la zone faillée de Teton, et faible sur la bordure sud de Jackson Hole. Les profondeurs estimées vont de 30m au sud, près des confluences des rivières Spring et Flat avec la rivière Snake, à 210m à l'ouest près de la ville de Wilson (Wyoming). Resumen Se llevó a cabo una campaña geofísica para determinar la profundidad del basamento de un acuífero libre en la zona sur de Jackson Hole, Wyoming, EEUU. USA. Medidas audio-magnetotelúricas (ATM) en 77 lugares de la zona de estudio dieron lugar a registros de resistividad eléctrica del subsuelo, que se usaron para inferir los cambios litológicos con la profundidad. Los depósitos superficiales, saturados y no consolidados de edad cuaternaria, el acuífero de Jackson, forman una capa de resistencia geoeléctrica entre 100-600ohm-m. La profundidad media de la base del acuífero de Jackson se estima en unos 61m (200pies), a partir de 62 registros con medidas suficientes. Los valores ATM fueron krigeados para obtener una medida de la profundidad del basamento del acuífero en la zona sur de Jackson Hole. Los mapas de isoprofundidades obtenidos por krigeado indican que el acuífero es poco profundo en la parte central de la zona de estudio, cerca de los Gros Ventre Buttes orientales y occidentales, más profundo al oeste, cerca del sistema de fallas de Teton, y menos profundo en el borde sur de Jackson Hole. Las profundidades van desde 30m (100pies) en el sur, en la confluencia entre los desfiladeros Spring y Flat con el Río Snake, hasta 210m (700pies) al oeste, cerca de la ciudad de Wilson, Wyoming.
Hsieh, Y Y; Chang, C C; Tsai, H D
2001-09-01
The zona pellucida (ZP) plays a protective role during fertilization and early embryonic development. It is related to sperm binding, the acrosome reaction, prevention of polyspermic fertilization, and holding blastomeres together before the morular stage. Zona-free oocytes are accidentally encountered. If these oocytes are healthy, they can be fertilized normally by intracytoplasmic sperm injection (ICSI). We reported on a couple with male infertility undergoing oocyte retrieval after ovarian hyperstimulation. Before the ICSI procedure, cumulus cells surrounding the oocytes were removed, which resulted in one oocyte escaping from its ZP. The zona-free oocyte was fertilized normally with ICSI and developed to the 8-cell stage. We observed that the zona-free zygote had the ability to further divide, despite its loose contact. The zona-free embryo was transferred with other zona-intact embryos, but the implantation failed. We conclude that zona-free oocytes can be rescued, fertilized with ICSI, and cultured for further transfer or cryopreservation.
NASA Astrophysics Data System (ADS)
Meseguer Valdenebro, Jose Luis
Electric arc welding processes represent one of the most used techniques on manufacturing processes of mechanical components in modern industry. The electric arc welding processes have been adapted to current needs, becoming a flexible and versatile way to manufacture. Numerical results in the welding process are validated experimentally. The main numerical methods most commonly used today are three: finite difference method, finite element method and finite volume method. The most widely used numerical method for the modeling of welded joints is the finite element method because it is well adapted to the geometric and boundary conditions in addition to the fact that there is a variety of commercial programs which use the finite element method as a calculation basis. The content of this thesis shows an experimental study of a welded joint conducted by means of the MIG welding process of aluminum alloy 6063-T5. The numerical process is validated experimentally by applying the method of finite element through the calculation program ANSYS. The experimental results in this paper are the cooling curves, the critical cooling time t4/3, the weld bead geometry, the microhardness obtained in the welded joint, and the metal heat affected zone base, process dilution, critical areas intersected between the cooling curves and the curve TTP. The numerical results obtained in this thesis are: the thermal cycle curves, which represent both the heating to maximum temperature and subsequent cooling. The critical cooling time t4/3 and thermal efficiency of the process are calculated and the bead geometry obtained experimentally is represented. The heat affected zone is obtained by differentiating the zones that are found at different temperatures, the critical areas intersected between the cooling curves and the TTP curve. In order to conclude this doctoral thesis, an optimization has been conducted by means of the Taguchi method for welding parameters in order to obtain an improvement on mechanical properties in aluminum metal joint. Los procesos de soldadura por arco electrico representan unas de las tecnicas mas utilizadas en los procesos de fabricacion de componentes mecanicos en la industria moderna. Los procesos de soldeo por arco se han adaptado a las necesidades actuales, haciendose un modo de fabricacion flexible y versatil. Los resultados obtenidos numericamente en el proceso de soldadura son validados experimentalmente. Los principales metodos numericos mas empleados en la actualidad son tres, metodo por diferencias finitas, metodos por elementos finitos y metodo por volumenes finitos. El metodo numerico mas empleado para el modelado de uniones soldadas, es el metodo por elementos finitos, debido a que presenta una buena adaptacion a las condiciones geometricas y de contorno ademas de que existe una diversidad de programas comerciales que utilizan el metodo por elementos finitos como base de calculo. Este trabajo de investigacion presenta un estudio experimental de una union soldada mediante el proceso MIG de la aleacion de aluminio 6063-T5. El metodo numerico se valida experimentalmente aplicando el metodo de los elementos finitos con el programa de calculo ANSYS. Los resultados experimentales obtenidos son: las curvas de enfriamiento, el tiempo critico de enfriamiento t4/3, geometria del cordon, microdurezas obtenidas en la union soldada, zona afectada termicamente y metal base, dilucion del proceso, areas criticas intersecadas entre las curvas de enfriamiento y la curva TTP. Los resultados numericos son: las curvas del ciclo termico, que representan tanto el calentamiento hasta alcanzar la temperatura maxima y un posterior enfriamiento. Se calculan el tiempo critico de enfriamiento t4/3, el rendimiento termico y se representa la geometria del cordon obtenida experimentalmente. La zona afectada termicamente se obtiene diferenciando las zonas que se encuentran a diferentes temperaturas, las areas criticas intersecadas entre las curvas de enfriamiento y la curva TTP. Para finalizar el trabajo de investigacion se ha realizado una optimizacion, con la aplicacion del metodo de Taguchi, de los parametros de soldeo con el objetivo de obtener una mejora sustancial en las propiedades mecanicas de las uniones metalicas de aluminio.
Heterogeneous levels of oxidative phosphorylation enzymes in rat adrenal glands.
Ogawa, Koichi; Harada, Keita; Endo, Yutaka; Sagawa, Sueko; Inoue, Masumi
2011-01-01
Mitochondria are organelles that produce ATP and reactive oxygen species, which are thought to be responsible for a decline in physiological function with aging. In this study, we morphologically and biochemically examined mitochondria in the rat adrenal gland. Immunohistochemistry showed that the rank order for intensity of immunolabelling for complex IV was zona reticularis > zona fasciculata > adrenal medulla, whereas for complex V α and β subunits, it was zona fasciculata > zona reticularis and adrenal medulla. The immunolabelling for complex I was homogeneous in the adrenal gland. The difference in immunolabelling between complexes I and IV indicates that the ratio of levels of complex I to that of complex IV in the zona reticularis was smaller than that in the zona fasciculata and the adrenal medulla. Electron microscopy revealed that aging rats had zona reticularis cells with many lysosomes and irregular nuclei. The result suggests that the level of proteins involved in oxidative phosphorylation is coordinated within the complex, but differs between the complexes. This might be responsible for degeneration of zona reticularis cells with aging. Copyright © 2009 Elsevier GmbH. All rights reserved.
Analysis of the maximum discharge of karst springs
NASA Astrophysics Data System (ADS)
Bonacci, Ognjen
2001-07-01
Analyses are presented of the conditions that limit the discharge of some karst springs. The large number of springs studied show that, under conditions of extremely intense precipitation, a maximum value exists for the discharge of the main springs in a catchment, independent of catchment size and the amount of precipitation. Outflow modelling of karst-spring discharge is not easily generalized and schematized due to numerous specific characteristics of karst-flow systems. A detailed examination of the published data on four karst springs identified the possible reasons for the limitation on the maximum flow rate: (1) limited size of the karst conduit; (2) pressure flow; (3) intercatchment overflow; (4) overflow from the main spring-flow system to intermittent springs within the same catchment; (5) water storage in the zone above the karst aquifer or epikarstic zone of the catchment; and (6) factors such as climate, soil and vegetation cover, and altitude and geology of the catchment area. The phenomenon of limited maximum-discharge capacity of karst springs is not included in rainfall-runoff process modelling, which is probably one of the main reasons for the present poor quality of karst hydrological modelling. Résumé. Les conditions qui limitent le débit de certaines sources karstiques sont présentées. Un grand nombre de sources étudiées montrent que, sous certaines conditions de précipitations extrêmement intenses, il existe une valeur maximale pour le débit des sources principales d'un bassin, indépendante des dimensions de ce bassin et de la hauteur de précipitation. La modélisation des débits d'exhaure d'une source karstique n'est pas facilement généralisable, ni schématisable, à cause des nombreuses caractéristiques spécifiques des écoulements souterrains karstiques. Un examen détaillé des données publiées concernant quatre sources karstiques permet d'identifier les raisons possibles de la limitation de l'écoulement maximal: (1) la dimension limitée du conduit karstique, (2) l'écoulement en charge, (3) le débordement dans un autre bassin, (4) le débordement du réseau s'écoulant vers la source principale par des sources temporaires dans le même bassin, (5) le stockage d'eau dans la zone surmontant l'aquifère karstique ou la zone épikarstique du bassin, et (6) des facteurs tels que le climat, le sol et le couvert végétal, l'altitude et la géologie du bassin d'alimentation. Le phénomène de capacité limitée du débit maximal des sources karstiques n'est pas pris en compte dans la modélisation des processus de précipitation-ruissellement, ce qui est probablement une des principales raisons de l'actuelle médiocre qualité de la modélisation hydrologique du karst. Resumen. Se presenta un análisis de las condiciones que limitan la descarga de algunos manantiales kársticos. Un elevado número de los manantiales estudiados muestra que, bajo condiciones de precipitación extremadamente intensa, hay un valor máximo para la descarga de los manantiales principales de la cuenca, independientemente del tamaño de ésta y del volumen de precipitación. La modelación de la descarga de manantiales kársticos no es fácil de generalizar y esquematizar debido a la existencia de numerosas características que son inherentes a los sistemas kársticos de flujo. A partir del estudio detallado de los datos publicados sobre cuatro manantiales kársticos, se identificó las posibles causas de la existencia de un caudal máximo de descarga: (1) el tamaño limitado del conducto kárstico, (2) el caudal surgente, (3) la descarga a otras cuencas, (4) el desbordamiento del sistema de flujo principal hacia manantiales intermitentes dentro de la misma cuenca, (5) el almacenamiento de agua en la zona superior del acuífero kárstico o zona epikárstica de la cuenca, y (6) factores tales como el clima, suelo y cubierta vegetal, y la altitud y geología de la zona de captación. La limitación de la descarga máxima de los manantiales kársticos no ha sido incluida en la modelación del proceso lluvia-escorrentía, hecho que probablemente es esencial para explicar los resultados poco satisfactorios de la modelación hidrológica de sistemas kársticos.
Jin, Mayuko; Fujiwara, Eiji; Kakiuchi, Yasutaka; Okabe, Masaru; Satouh, Yuhkoh; Baba, Shoji A.; Chiba, Kazuyoshi; Hirohashi, Noritaka
2011-01-01
To fuse with oocytes, spermatozoa of eutherian mammals must pass through extracellular coats, the cumulus cell layer, and the zona pellucida (ZP). It is generally believed that the acrosome reaction (AR) of spermatozoa, essential for zona penetration and fusion with oocytes, is triggered by sperm contact with the zona pellucida. Therefore, in most previous studies of sperm–oocyte interactions in the mouse, the cumulus has been removed before insemination to facilitate the examination of sperm–zona interactions. We used transgenic mouse spermatozoa, which enabled us to detect the onset of the acrosome reaction using fluorescence microscopy. We found that the spermatozoa that began the acrosome reaction before reaching the zona were able to penetrate the zona and fused with the oocyte's plasma membrane. In fact, most fertilizing spermatozoa underwent the acrosome reaction before reaching the zona pellucida of cumulus-enclosed oocytes, at least under the experimental conditions we used. The incidence of in vitro fertilization of cumulus-free oocytes was increased by coincubating oocytes with cumulus cells, suggesting an important role for cumulus cells and their matrix in natural fertilization. PMID:21383182
DOE Office of Scientific and Technical Information (OSTI.GOV)
East, I.J.; Keenan, A.M.; Larson, S.M.
1984-08-31
The zona pellucida is an extracellular glycocalyx, made of three sulfated glycoproteins, that surrounds mammalian oocytes. Parenterally administered monoclonal antibodies specific for ZP-2, the most abundant zona protein, localize in the zona pellucida. When labeled with iodine-125, these monoclonal antibodies demonstrate a remarkably high target-to-nontarget tissue ratio and provide clear external radioimaging of ovarian tissue.
Morphology and ultrastructure of the adrenal gland in Bactrian camels (Camelus bactrianus).
Ye, Wen-Ling; Wang, Feng-Ling; Wang, Hong-Ju; Wang, Jian-Lin
2017-04-01
In the present study, we examined the morphological features of the adrenal gland in Bactrian camel by means of digital anatomy, light and electron microscopy. Our findings testified that the gland was divided into three parts, capsule, cortex and medulla from outside to inside as other mammals, and the cortex itself was further distinguished into four zones: zona glomerulosa, zona intermedia, zona fasciculate and zona reticularis. Notably, the zona intermedia could be seen clearly in the glands from females and castrated males, whereas it was not morphologically clear in male. There was a great deal of lipid droplets in the zona fasciculate, while it was fewer in the zona glomerulosa and zona reticularis. The cytoplasm of adrenocortical cell contained rich mitochondria and endoplasmic reticulum. The adrenal medulla was well-developed with two separations of external and internal zones. The most obvious histological property of adrenal medulla cells were that they contained a huge number of electron-dense granules enveloped by the membrane, and so medulla cells could be divided into norepinephrine cells and epinephrine cells. Moreover, the cortical cuffs were frequently present in adrenal gland. Results of this study provides a theoretical basis necessary for ongoing investigations on Bactrian camels and their good adaptability in arid and semi-arid circumstances. Copyright © 2017 Elsevier Ltd. All rights reserved.
A Simple Economic Model of Cocaine Production
1994-01-01
University of New Mexico Press: Albuquerque (revised editionL 1988 11. "Plan de F*ecucion del Proyecto de Desarrollo Rural Integral del Alto Huallaga...ensuing raw material supplies (an industrial altenative)? This policy is represented in the model by ’Onewould alsohaeummakwbEr de otu of thsenw eprse...tht iemantngpoWAMdualoldi dieweinvesumaitisdie sa.sdietoldieoutpu ~~maahth~~~~ lnu~Ti srpemtdi dwemodelbyaeng diet die tota bacor A~l, ssousud it de nw
NASA Astrophysics Data System (ADS)
Kim, Youn Jong; Hamm, Se-Yeong
Groundwater contamination is becoming a major environmental problem in South Korea with the marked expansion of the industrial base and the explosive growth of the population. Even in rural areas, the increased use of fertilizers and pesticides, the presence of acid-mine drainage, and increase of volumes of domestic wastewaters are adding to groundwater pollution. The DRASTIC/EGIS model was used to evaluate the potential for groundwater contamination in the Cheongju city area, the first of several pilot studies. The model allows the designation of hydrogeologic settings within the study area, based on a composite description of all the major geologic and hydrogeologic factors for each setting. Then, a scheme for relative ranking of the hydrogeologic factors is applied to evaluate the relative vulnerability to groundwater contamination of each hydrogeologic setting. DRASTIC/EGIS can serve as a tool to evaluate pollution potential and so facilitate programs to protect groundwater resources. Résumé La contamination de l'eau souterraine devient un problème environnemental majeur en Corée du Sud, en relation avec le développement industriel bien marqué et l'explosion démographique. Meme dans les zones rurales, l'utilisation accrue d'engrais et de pesticides, le drainage acide de mines et les rejets croissants d'eaux usées contribuent à la pollution des nappes. Le modèle DRASTIC/EGIS a été utilisé pour évaluer le potentiel de contamination des eaux souterraines dans la région de la ville de Cheongju, la première de plusieurs régions pilotes. Le modèle permet de définir des ensembles hydrogéologiques dans la région étudiée, à partir de la description composite de tous les facteurs géologiques et hydrogéologiques essentiels pour chaque ensemble. Ensuite, un schéma pour le classement des facteurs hydrogéologiques est mis en oeuvre pour évaluer la vulnérabilité relative à la contamination des eaux souterraines pour chaque ensemble. DRASTIC/EGIS peut servir d'outil d'évaluation du potentiel de pollution et ainsi faciliter des plans de protection des ressources en eau souterraines. Resumen La contaminación de aguas subterráneas, debida a la expansión industrial y al fuerte crecimiento demográfico, supone un gran problema medioambiental en Corea del Sur. También en áreas rurales, el incremento en el uso de fertilizantes y pesticidas, el drenaje de minas y el aumento de los caudales de aguas residuales provocan un aumento de la contaminación. Para evaluar el riesgo de contaminación de las aguas subterráneas en el área de la ciudad de Cheongju, el primero de una serie de estudios piloto, se utilizó el modelo DRASTIC/EGIS. Este modelo permite la zonificación del área de estudio, basada en consideraciones geológicas e hidrogeológicas. En cada una de las zonas se aplica un esquema de clasificación que evalúa su vulnerabilidad relativa. El modelo DRASTIC/EGIS puede servir como una herramienta para evaluar el riesgo potencial de contaminación que facilite la creación de programas de protección de los recursos subterráneos.
DOT National Transportation Integrated Search
2011-05-01
Congested roadways in Texas metropolitan centers are important arteries for transporting : agricultural commodities into domestic and international markets. Truck transportation of these : commodities contributes to the observed congestion and del...
Erol, B; Avci, A; Eken, C; Ozgok, Y
2009-01-01
Zona zoster infection is often associated with painful erythematous vesicular eruptions of the skin or mucous membranes. Varicella zoster virus which stays latent in the sensorial root ganglia causes zona zoster infection. The most recognized feature of zona zoster is the dermatomal distribution of vesicular rashes. In the present case report, we state an unusual presentation of sacral zona zoster with urinary retention, erectile dysfunction and meningitis. Copyright 2009 S. Karger AG, Basel.
Zhou, Junhua; Lam, Brian; Neogi, Sudeshna G; Yeo, Giles S H; Azizan, Elena A B; Brown, Morris J
2016-12-01
Primary aldosteronism is present in ≈10% of hypertensives. We previously performed a microarray assay on aldosterone-producing adenomas and their paired zona glomerulosa and fasciculata. Confirmation of top genes validated the study design and functional experiments of zona glomerulosa selective genes established the role of the encoded proteins in aldosterone regulation. In this study, we further analyzed our microarray data using AmiGO 2 for gene ontology enrichment and Ingenuity Pathway Analysis to identify potential biological processes and canonical pathways involved in pathological and physiological aldosterone regulation. Genes differentially regulated in aldosterone-producing adenoma and zona glomerulosa were associated with steroid metabolic processes gene ontology terms. Terms related to the Wnt signaling pathway were enriched in zona glomerulosa only. Ingenuity Pathway Analysis showed "NRF2-mediated oxidative stress response pathway" and "LPS (lipopolysaccharide)/IL-1 (interleukin-1)-mediated inhibition of RXR (retinoid X receptor) function" were affected in both aldosterone-producing adenoma and zona glomerulosa with associated genes having up to 21- and 8-fold differences, respectively. Comparing KCNJ5-mutant aldosterone-producing adenoma, zona glomerulosa, and zona fasciculata samples with wild-type samples, 138, 56, and 59 genes were differentially expressed, respectively (fold-change >2; P<0.05). ACSS3, encoding the enzyme that synthesizes acetyl-CoA, was the top gene upregulated in KCNJ5-mutant aldosterone-producing adenoma compared with wild-type. NEFM, a gene highly upregulated in zona glomerulosa, was upregulated in KCNJ5 wild-type aldosterone-producing adenomas. NR4A2, the transcription factor for aldosterone synthase, was highly expressed in zona fasciculata adjacent to a KCNJ5-mutant aldosterone-producing adenoma. Further interrogation of these genes and pathways could potentially provide further insights into the pathology of primary aldosteronism. © 2016 The Authors.
Causes of sinks near Tucson, Arizona, USA
NASA Astrophysics Data System (ADS)
Hoffmann, John P.; Pool, Donald R.; Konieczki, A. D.; Carpenter, Michael C.
Land subsidence in the form of sinks has occurred on and near farmlands near Tucson, Pima County, Arizona, USA. The sinks occur in alluvial deposits along the flood plain of the Santa Cruz River, and have made farmlands dangerous and unsuitable for farming. More than 1700 sinks are confined to the flood plain of the Santa Cruz River and are grouped along two north-northwestward-trending bands that are approximately parallel to the river and other flood-plain drainages. An estimated 17,000m3 of sediment have been removed in the formation of the sinks. Thirteen trenches were dug to depths of 4-6m to characterize near-surface sediments in sink and nonsink areas. Sediments below about 2m included a large percentage of dispersive clays in sink areas. Sediments in nonsink areas contain a large component of medium- to coarse-grained, moderately to well sorted sand that probably fills a paleochannel. Electromagnetic surveys support the association of silts and clays in sink areas that are highly electrically conductive relative to sand in nonsink areas. Sinks probably are caused by the near-surface process of subsurface erosion of dispersive sediments along pre-existing cracks in predominantly silt and clay sediments. The pre-existing cracks probably result from desiccation or tension that developed during periods of water-table decline and channel incision during the past 100 years or in earlier periods. Résumé Des effondrements en forme d'entonnoir se sont produits sur et près d'exploitations agricoles de Pima (Arizona). Ces entonnoirs apparaissent dans les alluvions le long de la plaine d'inondation de la rivière Santa Cruz ; ils ont rendu ces terrains dangereux et inexploitables pour l'agriculture. Plus de 1700 entonnoirs existent dans la plaine d'inondation de la rivière Santa Cruz et sont groupés en deux bandes orientées nord-nord-ouest, approximativement parallèles à la rivière et aux autres chenaux de la plaine d'inondation. Un volume de sédiments estiméà 17,000m3 a été entraîné lors de la formation de ces entonnoirs. Treize tranchées ont été creusées à des profondeurs de 4 à 6m afin de caractériser les sédiments proches de la surface dans les zones avec et sans entonnoirs. Les sédiments situés à 2m environ sous la surface contiennent un fort pourcentage d'argile dispersée, dans les zones à entonnoirs. Dans les zones sans entonnoirs, la granulométrie des sédiments est constituée en fortes proportions de sables moyens à grossiers, moyennement à bien lités, qui remplissent probablement un ancien chenal. Des levés électromagnétiques montrent que l'association de silts et d'argiles dans les zones à entonnoirs possède une forte conductivitéélectrique, par comparaison avec les sables des zones sans entonnoirs. Les entonnoirs sont dus probablement à des processus, proches de la surface, d'érosion souterraine des sédiments constitués surtout de silts et d'argiles. Les fractures préexistantes résultent sans doute de la dessiccation ou de la tension se produisant lors des périodes d'abaissement de la nappe, liéà l'enfoncement du lit de la rivière au cours des cent dernières années ou même avant.1 Resumen Se ha detectado la formación de dolinas como resultado de la subsidencia que ha tenido lugar en las zonas agrícolas Condado de Pima, Arizona, EEUU. Estos colapsos han aparecido en depósitos aluviales a lo largo de la llanura de inundación del Río Santa Cruz y han hecho que las zonas agrícolas sean peligrosas e inadecuadas para su uso. Las más de 1700 dolinas aparecidas se agrupan a lo largo de dos bandas con dirección nor-noroeste, paralelas al río y a otros ejes de drenaje del llano. Se ha estimado un desplazamiento de 17.000metros cúbicos de sedimentos para formar estas dolinas. Se excavaron trece zanjas de entre 4 y 6metros para caracterizar los sedimentos más superficiales tanto en áreas colapsadas como no colapsadas. Por debajo de los dos metros de profundidad, los sedimentos presentan altos porcentajes de arcillas dispersivas en las zonas de dolinas. En las zonas en que no se han producido colapsos, se aprecian altos contenidos de arena de grano entre mediano y grueso, con una granulometría entre moderada y bastante uniforme, que probablemente rellenan un paleocanal. Las campañas electromagnéticas confirman la asociación entre los materiales arcillosos, eléctricamente conductivos, y la presencia de dolinas, mientras que los materiales arenosos, menos conductivos eléctricamente, se asocian a las zonas no colapsadas. Las dolinas se deben probablemente a procesos de erosión subsuperficial de los sedimentos arcillosos a lo largo de fracturas preexistentes. Estas fracturas se produjeron probablemente como resultado de la desecación del suelo en los periodos de descenso del nivel freático, en los últimos cien años.
The Investigation of Mass Transfer in the Karasu Karstic Aquifer, Konya, Turkey
NASA Astrophysics Data System (ADS)
Ozdemir, Adnan; Nalbantcilar, Tahir
2002-09-01
In this study, the changes in the chemical composition of the groundwater along a flow path were examined by using the water samples collected from unconfined, semi-confined and confined parts of the Karasu karstic aquifer. It was determined that transport of bicarbonate, calcium, and magnesium was dominant in unconfined and semi-confined parts of the aquifer, whereas calcite and dolomite precipitate in the confined parts. On the other hand, gypsum dissolution is present in all parts of the aquifer. In addition, the computed saturation indices explain the occurrences and precipitation of travertines in the Goksu Valley, which is the discharge area for the aquifer. Résumé. Les modifications de la composition chimique de l'eau souterraine le long d'un axe d'écoulement ont été étudiées à partir d'échantillons prélevés dans les parties libres, semi-captives et captives de l'aquifère karstique de Karasu. On a mis en évidence que le transport de carbonate, de calcium et de magnésium est prépondérant dans les parties libres et semi-captives de l'aquifère, alors que la calcite et la dolomite précipitent dans les parties captives. En outre, la dissolution du gypse se produit dans toutes les parties de l'aquifère. Par ailleurs, les indices de saturation calculés rendent compte de l'existence et de la précipitation des travertins dans la vallée du Göksu, qui est la zone de décharge de cet aquifère. Resumen. En este estudio, se han examinado los cambios de composición química en las aguas subterráneas a lo largo de una línea de corriente mediante el análisis de muestras recogidas en partes libres, semiconfinadas y cautivas del acuífero cárstico de Karasu. Se ha determinado que el transporte de bicarbonato, calcio y magnesio es dominante en las zonas libres y semiconfinadas, mientras que la calcita y la dolomita precipitan en las zonas confinadas. Por otro lado, la disolución de yesos ocurre en todo el ámbito del acuífero. Además, los índices de saturación calculados explican la existencia y precipitación de travertinos en el Valle de Goksu, situado en el área de descarga del acuífero.
Cuerda, Cristina; Álvarez, Julia; Ramos, Primitivo; Abánades, Juan Carlos; García-de-Lorenzo, Abelardo; Gil, Pedro; De-la-Cruz, Juan José
2016-03-25
Introducción: la desnutrición relacionada con la enfermedad (DRE) es un problema sociosanitario frecuente que afecta preferentemente a los mayores de 65 años, que aumenta la morbimortalidad y disminuye la calidad de vida. Objetivo: estudiar la prevalencia de DRE en mayores de 65 años en diferentes centros sociosanitarios del Servicio Regional de Bienestar Social de la Comunidad de Madrid. Métodos: estudio transversal en 33 centros sociosanitarios de Madrid (6 centros de atención primaria [AP], 9 centros de mayores [CM], 9 hospitales [H] y 9 residencias [R]) seleccionados mediante muestreo polietápico. Las variables estudiadas fueron edad, sexo, nivel de dependencia según la escala de incapacidad de la Cruz Roja, motivo de ingreso y enfermedad de base, hábitat (urbano-periurbano-rural) y distribución geográfica (norte centro-sur). Como herramienta de cribado nutricional se utilizó el Mini Nutritional Assessment (MNA-cribaje) en todos los centros. En los pacientes con cribado positivo (en riesgo-desnutrición) se realizó el MNA-evaluación. El estudio estadístico se realizó con el paquete SSS 21.0 e incluyó estadística descriptiva, test de Chi-cuadrado y prueba exacta de Fisher, ANOVA de un factor, Kruskal-Wallis y análisis de regresión logística (RL) binaria univariante y multivariante. Se consideró significación estadística p < 0,05. Resultados: se reclutaron 1.103 sujetos (275 AP, 278 CM, 281 H, 269 R), edad media de 79,5 ± 8,4 años (41,2% varones, 58,8% mujeres). Los sujetos procedentes de H y R tuvieron un mayor grado de incapacidad (p < 0,001). La prevalencia global de DRE fue del 10%, encontrándose un 23,3% en riesgo de desnutrición, con diferencias entre los cuatro tipos de centros sociosanitarios (p < 0,001). El análisis univariante de RL mostró diferencia significativas en la prevalencia de desnutrición según la edad, sexo, grado de dependencia, tipo de centro sociosanitario, hábitat y zona geográfica. Sin embargo, en el análisis multivariante solo el grado de dependencia, el tipo de centro y el hábitat tuvieron significación estadística. Conclusiones: la prevalencia de DRE en mayores de 65 años en la Comunidad de Madrid es del 10%, encontrándose además un 23,3% en riesgo de desnutrición. Las únicas variables que se relacionaron de forma independiente con la desnutrición en el análisis multivariante fueron el nivel de dependencia de los pacientes y el tipo y hábitat de centro sociosanitario.
The anatomy of the caudal zona incerta in rodents and primates
Watson, Charles; Lind, Christopher R P; Thomas, Meghan G
2014-01-01
The caudal zona incerta is the target of a recent modification of established procedures for deep brain stimulation (DBS) for Parkinson's disease and tremor. The caudal zona incerta contains a number of neuronal populations that are distinct in terms of their cytoarchitecture, connections, and pattern of immunomarkers and is located at a position where a number of major tracts converge before turning toward their final destination in the forebrain. However, it is not clear which of the anatomical features of the region are related to its value as a target for DBS. This paper has tried to identify features that distinguish the caudal zona incerta of rodents (mouse and rat) and primates (marmoset, rhesus monkey, and human) from the remainder of the zona incerta. We studied cytoarchitecture, anatomical relationships, the pattern of immunomarkers, and gene expression in both of these areas. We found that the caudal zona incerta has a number of histological and gene expression characteristics that distinguish it from the other subdivisions of the zona incerta. Of particular note are the sparse population of GABA neurons and the small but distinctive population of calbindin neurons. We hope that a clearer appreciation of the anatomy of the region will in the end assist the interpretation of cases in which DBS is used in human patients. PMID:24138151
Human sperm bind to the N-terminal domain of ZP2 in humanized zonae pellucidae in transgenic mice
Baibakov, Boris; Boggs, Nathan A.; Yauger, Belinda; Baibakov, Galina
2012-01-01
Fertilization requires taxon-specific gamete recognition, and human sperm do not bind to zonae pellucidae (ZP1–3) surrounding mouse eggs. Using transgenesis to replace endogenous mouse proteins with human homologues, gain-of-function sperm-binding assays were established to evaluate human gamete recognition. Human sperm bound only to zonae pellucidae containing human ZP2, either alone or coexpressed with other human zona proteins. Binding to the humanized matrix was a dominant effect that resulted in human sperm penetration of the zona pellucida and accumulation in the perivitelline space, where they were unable to fuse with mouse eggs. Using recombinant peptides, the site of gamete recognition was located to a defined domain in the N terminus of ZP2. These results provide experimental evidence for the role of ZP2 in mediating sperm binding to the zona pellucida and support a model in which human sperm–egg recognition is dependent on an N-terminal domain of ZP2, which is degraded after fertilization to provide a definitive block to polyspermy. PMID:22734000
Mugnier, Sylvie; Boittin, Stéphane; Douet, Cécile; Monget, Philippe; Magistrini, Michèle; Goudet, Ghylène
2008-11-14
In human and rodents, sperm-zona pellucida binding is mediated by a sperm surface Galactosyltransferase that recognizes N-Acetylglucosamine residues on a glycoprotein ZPC. In large domestic mammals, the role of these molecules remains unclear: in bovine, they are involved in sperm-zona pellucida binding, whereas in porcine, they are not necessary. Our aim was to clarify the role of Galactosyltransferase and N-Acetylglucosamine residues in sperm-zona pellucida binding in ungulates. For this purpose, we analyzed the mechanism of sperm-zona pellucida interaction in a third ungulate: the horse, since the Galactosyltransferase and N-Acetylglucosamine residues have been localized on equine gametes. We masked the Galactosyltransferase and N-Acetylglucosamine residues before the co-incubation of gametes. Galactosyltransferase was masked either with an anti-Galactosyltransferase antibody or with the enzyme substrate, UDP Galactose. N-Acetylglucosamine residues were masked either with a purified Galactosyltransferase or with an anti-ZPC antibody. The number of spermatozoa bound to the zona pellucida did not decrease after the masking of Galactosyltransferase or N-Acetylglucosamine. So, these two molecules may not be necessary in the mechanism of in vitro sperm-zona pellucida interaction in the horse. The involvement of Galactosyltransferase and N-Acetylglucosamine residues in sperm-zona pellucida binding may have been lost during evolution in some ungulates, such as porcine and equine species.
NASA Astrophysics Data System (ADS)
Cheng, Jianmei; Chen, Chongxi; Ji, Menrui
The main task of studies on salt-water intrusion into coastal confined aquifers is to predict the position of the fresh- salt-water interface, which can be determined from the length of the aquifer roof extending under the sea. Records of groundwater level affected by tides can be used to infer hydrological conditions and determine hydraulic parameters of an aquifer extending under the sea. In this paper, a three-dimensional, variable-density groundwater flow model has been developed to determine the equivalent roof length of an aquifer extending under the sea from the tidal-effected data of groundwater level in the Jahe River Basin, Shandong Province, China. The seaward boundary is obtained by converging hydraulic head fluctuations observed in drill holes with calculated values, and the aquifer parameters in the extending zone are estimated. The impacts of aquifer roof length and aquifer parameters on the fluctuation of tidal groundwater are studied. It is concluded that the length of the aquifer roof extending under the sea should correspond with certain aquifer parameters in the extrapolation zone. Therefore, the seaward boundary determined from tidal-effect information is the equivalent boundary in hydrodynamic characteristics rather than the true boundary of the confined aquifer Les sujets principaux des études d'instrusion saline dans les aquifères confinés en zone côtière sont la prédiction de la position de l'interface entre l'eau salée et l'eau fraîche, qui peut être déterminée à partir de l'extention du toit de l'aquifère sous la mer. Les enregistrements des niveaux des eaux souterraines influencés par les marées peuvent être utilisés pour préciser les conditions hydrologiques et déterminer les paramètres hydrauliques d'un aquifère possédant une extension sous la mer. Dans cet article, un modèle tridimensionnel comprenant des eaux souterraines de densité variable a été développé pour déterminer la longueur équivalente du toit d'un aquifère qui s'étend sous la mer à partir des données concernant les effets de marée sur les eaux souterraines dans le bassin de la rivière Jahe, dans la province de Shandong, Chine. La limite de salinité est déterminée en faisant converger les fluctuations des hauteurs piézométriques avec les valeurs calculées, et les paramètres de l'aquifère sont estimés dans la zone s'étendant sous la mer. L'incidence de la longueur de l'aquifère sous la mer sur les fluctuations des niveaux est étudiée. On en conclut que la longueur du toit de l'aquifère sous la mer peut correspondre à certains aquifères paramètres dans la zone d'extrapolation. Par conséquent, la limite de salinité déterminée à partir des effets de marée est l'équivalent d'une limite hydrodynamique plutôt que la véritable limite de l'aquifère. El principal objetivo de los estudios sobre intrusiones de agua salada en acuíferos costeros confinados es predecir la posición de la interfase agua dulce-agua salada, la cual puede determinarse a partir de la longitud del techo del acuífero que se extiende por debajo del mar. Los registros de niveles de agua subterránea afectados por las mareas puede utilizarse para inferir las condiciones hidrológicas y determinar los parámetros hidráulicos de un acuífero que se extiende por debajo del mar. En este artículo se ha desarrollado un modelo de flujo tri-dimensional de agua subterránea de densidad variable para determinar la longitud del techo equivalente de un acuífero que se extiende por debajo del mar a partir de datos, afectados por la marea, de niveles de agua subterránea en la Cuenca del Río Jahe, Provincia Shandong, China. El límite hacia el océano se obtiene por convergencia de fluctuaciones de presiones hidráulicas observadas en pozos con valores calculados, y se estiman los parámetros del acuífero en la zona extendida. Se estudian los impactos de la longitud del techo del acuífero y los parámetros del acuífero en la fluctuación del agua subterránea afectada por las mareas. Se concluye que la longitud del techo del acuífero que se extiende por debajo del mar debería corresponder con ciertos parámetros del acuífero en la zona de extrapolación. Por lo tanto, el límite hacia el océano determinado a partir de información de efectos de marea es el límite equivalente en características hidrodinámicas más que el límite real del acuífero confinado.
Revitalizing Hispanic and Native American Communities: Four Examples.
ERIC Educational Resources Information Center
Robinson, Paul; And Others
1989-01-01
Describes locally controlled economic development strategies used by Native American and Hispanic cooperatives and organizations: Ganados del Valle, Madera Forest Products Association, Seventh Generation Fund, and Ramah Navajo Weavers Association. Discusses the issues of cultural and economic survival in isolated rural communities. (SV)
Hydrochemical tracers in the middle Rio Grande Basin, USA: 1. Conceptualization of groundwater flow
NASA Astrophysics Data System (ADS)
Plummer, L. Niel; Bexfield, Laura M.; Anderholm, Scott K.; Sanford, Ward E.; Busenberg, Eurybiades
Chemical and isotopic data for groundwater from throughout the Middle Rio Grande Basin, central New Mexico, USA, were used to identify and map groundwater flow from 12 sources of water to the basin, evaluate radiocarbon ages, and refine the conceptual model of the Santa Fe Group aquifer system. Hydrochemical zones, representing groundwater flow over thousands to tens of thousands of years, can be traced over large distances through the primarily siliciclastic aquifer system. The locations of the hydrochemical zones mostly reflect the ``modern'' predevelopment hydraulic-head distribution, but are inconsistent with a trough in predevelopment water levels in the west-central part of the basin, indicating that this trough is a transient rather than a long-term feature of the aquifer system. Radiocarbon ages adjusted for geochemical reactions, mixing, and evapotranspiration/dilution processes in the aquifer system were nearly identical to the unadjusted radiocarbon ages, and ranged from modern to more than 30 ka. Age gradients from piezometer nests ranged from 0.1 to 2 year cm-1 and indicate a recharge rate of about 3 cm year-1 for recharge along the eastern mountain front and infiltration from the Rio Grande near Albuquerque. There has been appreciably less recharge along the eastern mountain front north and south of Albuquerque. Des données sur les éléments chimiques et les isotopes présents dans l'eau souterraine prélevée à divers endroits dans le bassin moyen du Rio Grande, au centre du Nouveau-Mexique (É-U), ont permis de déterminer l'existence et l'étendue de douze sources d'eau régionales dans le bassin, d'évaluer les âges radiocarbones et de raffiner le modèle conceptuel du système aquifère du groupe de Santa Fe. Des zones hydro-chimiques qui représentent l'écoulement de l'eau souterraine depuis des dizaines de milliers d'années peuvent être suivies sur de longues distances à travers l'aquifère principalement siliclastique. La position des zones hydro-chimiques reflète principalement la distribution moderne des charges hydrauliques mais est incohérente avec une dépression dans le niveau d'eau dans la partie centre-ouest du bassin, ce qui indique que cette dépression est un élément transitoire du système aquifère plutôt qu'un élément à long terme. Les âges radiocarbones ajustés aux réactions géochimiques et aux processus de mélange et d'évapotranspiration/dilution qui ont lieu dans l'aquifère sont presque identiques aux âges non ajustés et varient de la période moderne jusqu'à 30 ka. Les gradients d'âge établis à partir des nids de piézomètres s'étendent de 0.1 à 2 a cm-1 et suggèrent un taux de recharge d'environ 3 cm a-1 le long du front des montagnes à l'est et pour l'infiltration provenant du Rio Grande près d'Albuquerque. Il y a eu substantiellement moins de recharge le long du front des montagnes à l'est, au nord et au sud d'Albuquerque. Se utilizaron datos químicos e isotópicos de agua subterránea a lo largo de la cuenca central del río Grande, Nuevo México, EEUU, para identificar y mapear el flujo de agua subterránea de 12 fuentes de agua a la cuenca para evaluar edades por medio de radio carbon y para refinar el modelo conceptual del sistema acuífero del Grupo Santa Fé. Se puede establecer zonas hidrotérmicas que representan el flujo de agua subterránea a lo largo de miles a miles de decenas de años en grandes distancias a través del sistema acuífero principalmente siliclástico. Las ubicaciones de las zonas hidroquímicas mayormente reflejan la distribucion de la cabeza hidráulica pre-desarollo moderna pero son inconsistentes con una depresión en los niveles de agua pre-desarollo en la zona central oeste de la cuenca. Esto indica que esta depresión es un rasgo transitorio y no un rasgo de largo plazo del sistema acuífero. Las edades de radio carbon ajustadas para los procesos de reaciones geoquímicas, de mezclado y de evapotranspiración-dilución son casi idénticas a los edades de radio carbon no ajustadas oscilan en un rango desde la modernidad a 30 mil años. Las gradientes de edad de nidos de piezometros van de 0.1 a 2 años cm-1 e indican un sitio de recarga de aproximadamente 3 cm/yr para la recarga a lo largo del frente montañoso oriental e infiltración del río Grande cerca de Albuquerque. Se aprecia una recarga menor a lo largo del frente oriental de montañas al norte y al sur de Albuquerque.
Differences between antigenic determinants of pig and cat zona pellucida proteins.
Jewgenow, K; Rohleder, M; Wegner, I
2000-05-01
Despite many efforts, the control of reproduction in feral cat populations is still a problem in urban regions around the world. Immunocontraception is a promising approach; thus the present study examined the suitability of the widely used pig zona pellucida proteins (pZP) for contraception in feral domestic cats. Purified zona pellucida proteins obtained from pig and cat ovaries were used to produce highly specific antisera in rabbits. Antibodies against pZP raised in rabbits or lions were not effective inhibitors of either in vitro sperm binding (cat spermatozoa to cat oocytes) or in vitro fertilization in cats, whereas antibodies against feline zona pellucida proteins (fZP) raised in rabbits showed a dose-dependent inhibition of in vitro fertilization. Immunoelectrophoresis, ELISA and immunohistology of ovaries confirmed these results, showing crossreactivity of anti-fZP sera to fZP and to a lesser extent to pZP, but no interaction of anti-pZP sera with fZP. It is concluded that cat and pig zonae pellucidae express a very small number of shared antigenic determinants, making the use of pZP vaccine in cats questionable. A contraceptive vaccine based on feline zona pellucida determinants will be a better choice for the control of reproduction in feral cats if immunogenity can be achieved.
Abordaje a la Cisterna Ambiens
Ajler, Pablo; Bravo, Michael Cruz; Garategui, Lucas; Goldschmidt, Ezequiel; Isolan, Gustavo; Campero, Álvaro
2016-01-01
Resumen Objetivo: Describir paso a paso el abordaje a la cisterna ambiens por la vía suboccipital retrosigmoidea supracerebelosa infratentorial (SRSI). Descripción: El abordaje SRSI se realiza de la misma manera que el abordaje suboccipital retrosigmoideo (SR), utilizado habitualmente para acceder a la patología del ángulo pontocerebeloso, con las siguientes modificaciones: (1) utilizamos siempre la posición semisentado, (2) la craneotomia-craniectomia debe exponer el seno transverso y extenderse 5 cm medialmente hacia el inion, (3) al realizar la apertura dural es necesario rebatir la duramadre junto con el seno transverso hacia cefálico con puntos de tracción, (4) bajo magnificación con microscopio quirúrgico se debe realizar la apertura de la cisterna cerebelobulbar para drenar líquido cefalorraquídeo, (5) en el plano supracerebeloso es fundamental cortar las bridas aracnoidales y de ser necesario debemos coagular y cortar las venas puente, todas estas maniobras sumadas al efecto de la gravedad brindan mayor apertura del corredor supracerebeloso. Conclusión: El abordaje a la cisterna ambiens por la vía SRSI es una opción segura para el acceso de patologías tumorales que se alojan en esta zona con un componente predominantemente infratentorial. PMID:27999709
Emergent and Reemergent Arboviruses in South America and the Caribbean: Why So Many and Why Now?
Marcondes, Carlos Brisola; Contigiani, Marta; Gleiser, Raquel Miranda
2017-05-01
Varios arbovirus han emergido y/o reemergido en el Nuevo Mundo en las últimas décadas. Los virus Zika y chikungunya, anteriormente restringidos a África y quizás Asia, invadieron el continente, causando gran preocupación; además siguen ocurriendo brotes causados por el virus dengue en casi todos los países, con millones de casos por año. El virus West Nile invadió rápidamente América del Norte, y ya se han encontrado casos en América Central y del Sur. Otros arbovirus, como Mayaro y el virus de la encefalitis equina del este han aumentado su actividad y se han encontrado en nuevas regiones. Se han documentado cambios en la patogenicidad de algunos virus que conducen a enfermedades inesperadas. Una fauna diversa de mosquitos, cambios climáticos y en la vegetación, aumento de los viajes, y urbanizaciones no planificadas que generan condiciones adecuadas para la proliferación de Aedes aegypti (L.), Culex quinquefasciatus Say y otros mosquitos vectores, se han combinado para influir fuertemente en los cambios en la distribución y la incidencia de varios arbovirus. Se enfatiza la necesidad de realizar estudios exhaustivos de la fauna de mosquitos y modificaciones de las condiciones ambientales, sobre todo en las zonas urbanas fuertemente influenciadas por factores sociales, políticos y económicos. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Marrero, Analía; Tudurí, Adriana; Pérez, Laura; Cuña, Caroline; Muniz, Pablo; Lopes Figueira, Rubens; Michaelovitch de Mahiques, Michel; Alves de Lima Ferreira, Paulo; Pittauerová, Daniela; Hanebuth, Till; García Rodríguez, Felipe
2014-12-01
El Río de la Plata (RdlP) presenta significativas variaciones naturales (hidrodinámicas y oceanográficas) asociadas a diferentes condiciones climáticas. El propósito de este trabajo es inferir los cambios de aportes continentales de sedimentos y su relación con las variaciones hidrológicas del Río de la Plata, a través del análisis de proxies sedimentológicos y geoquímicos en testigos de sedimentos de la plataforma interna uruguaya que registran los últimos 100 años, aproximadamente. A partir de la datación por 210Pb de dos testigos de sedimentos (GeoB 13813-4 y BAR1) se reconstruyó la geocronología del ambiente, y se relacionó con datos de las forzantes climáticas Pacific Decadal Oscillation, El Niño/La Niña Southern Oscillation, Atlantic Multidecadal Oscillation, y las anomalías hidrológicas de los ríos Paraná y Uruguay. Los valores más positivos y estables del Southern Oscillation Index, los cuales corresponden a fases La Niña, se observan en el periodo correspondiente entre 1910-1970, respecto al resto de la serie, donde se aprecia una mayor variabilidad y una tendencia hacia valores más negativos (eventos El Niño). Se hicieron dendrogramas (clustering) jerárquicos para ambos testigos. Para el testigo GeoB 13813-4, se utilizó la relación Ca/Ti y la granulometría, mientras que para BAR1 se recurrió a variables granulométricas y la tasa de sedimentación. El mayor aporte continental hacia la región de la plataforma adyacente al Río de la Plata registrado a partir del año 1970, podría ser el factor principal de los agrupamientos observados en los clusters para ambos testigos. Las agrupaciones mostraron una diferenciación en la década de 1970, lo que estaría asociado al aumento de los caudales de los ríos Paraná y Uruguay, durante las últimas tres décadas del siglo XX. Por otra parte se observa que la granulometría del testigo BAR1 presentó un mayor tamaño de grano y más variabilidad que en el caso del testigo GeoB 13813-4. También se determinó una mayor acumulación de sedimentos a través del tiempo en el cinturón de barro del Río de la Plata (plataforma continental adyacente), comparado con aquel registrado en la Barra del Indio (límite entre zona intermedia y externa del estuario). Estas diferencias podrían estar relacionadas con la influencia del Río de la Plata, el cual genera un ambiente altamente dinámico sobre la Barra del Indio y un ambiente más estable sobre el cinturón de barro en la plataforma continental.
Angio-OCT de la zona avascular foveal en ojos con oclusión venosa de la retina.
Wons, Juliana; Pfau, Maximilian; Wirth, Magdalena A; Freiberg, Florentina J; Becker, Matthias D; Michels, Stephan
2017-07-11
Objetivo: El objetivo del estudio comprendía visualizar y cuantificar las alteraciones patológicas de la zona avascular foveal (ZAF) mediante angio-OCT en ojos con oclusión venosa de la retina (OVR) en comparación con el ojo contralateral sano. Procedimientos: La angio-OCT se llevó a cabo mediante el sistema Avanti® RTVue 100 XR (Optovue Inc., Fremont, Calif., EE. UU.). Los bordes de la capa vascular superficial (CVS) se definieron como 3 μm por debajo de la membrana limitante interna y 15 μm por debajo de la capa plexiforme interna y, para la capa vascular profunda (CVP), como 15 y 70 μm por debajo de la membrana limitante interna y de la capa plexiforme interna, respectivamente. La longitud de la ZAF horizontal, vertical y máxima de la CVS y la CVP en cada ojo se midió de forma manual. Además, se midió el ángulo entre el diámetro máximo de la ZAF y el plano papilomacular. Resultados: La angio-OCT representó los defectos dentro de la vasculatura en el área perifoveal en ojos con oclusión de rama venosa de la retina (ORVR; n = 11) y con oclusión de la vena central de la retina (OVCR; n = 8). Esto resultó en un crecimiento del diámetro máximo de la ZAF en ojos con OVR (n = 19) en comparación con el ojo contralateral (n = 19; 921 ± 213 frente a 724 ± 145 µm; p = 0,008). Además, se observó una correlación significativa entre la mejor agudeza visual corregida (MAVC) y el diámetro máximo de la ZAF en la CVP (ρ de Spearman = -0,423, p < 0,01). Por último, en los ojos con OVR, el ángulo entre el plano papilomacular y el diámetro máximo de la ZAF se dio tan solo en el 21,05% (CVS) y en el 15,79% (CVP) de los casos a 0 ± 15 ó 90 ± 15°, respectivamente. En ojos sanos, estos ángulos (que supuestamente representan una configuración de la ZAF regular) fueron más prevalentes (CVS 68,42 frente a 21,05%, p = 0,003; CVP 73,68 frente a 15,79%, p < 0,001). Conclusiones: La angio-OCT muestra alteraciones morfológicas de la ZAF en ojos con OVCR y ORVR. La correlación del diámetro máximo de la ZAF con la MAVC indica que estas alteraciones resultan funcionalmente relevantes. © 2017 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Roldán, Francisco Javier; Azañon, Jose Miguel; Rodríguez, Jose; Mateos, Rosa Maria
2014-05-01
The synthesis and correlation of units carried out in the continuous geological map (Roldán et al., 2012), has revealed a fragmentation of the carbonate outcrops belong to the Subbetic Domain (García-Hernández et al., 1980). Subbetic NW verging thrust and fold axial traces have not lateral continuity and Jurassic carbonate outscrops appear as klippes on the olistotromic unit. These ductile structures that can be observed in the internal structure of these jurassic blocks are unrelated to the brittle-ductile deformation bands observed at the basal pelitic levels. Basal detachments are rooted in: a) the Olistostromic unit, a Upper Langhian-Lower Serravallian breccia constituted by gypsum-bearing clay and marls; b) Cretaceous-Tertiary marly sedimentary rocks (Rodríguez-Fernández, et al., 2013) . In both kind of rocks, cataclastic structures allows to infer a top-to-the WSW displacement. Paleostress measurements, made on these detachments levels, are compatible with a extensional regime (Roldán et al., 2012). At the same time, the analysis and interpretation of subsurface data (seismic surveys and borehole testing) shows that the Subbetic Domain (External Subbetic, Molina 1987) are affected by westward low-angle normal faults. A balanced cross-section, based on morphological and cartographic data in the area between Sierra de Cabra and Sierra de Alta Coloma (Valdepeñas de Jaén), shows plurikilometric displacements which has been produced during Late Serravallian-Early Tortonian times. References: García-Hernández, M., López-Garrido, A.C., Rivas, P., Sanz de Galdeano, C., Vera, J.A. (1980): Mesozoic paleogeographic evolution of the zones of the Betic Cordillera. Geol. Mijnb. 59 (2). 155-168. Molina, J.M. (1987). Análisis de facies del Mesozoico en el Subbético. Tesis Doctoral, Univ. Granada. 518 p. Rodríguez-Fernández, J., Roldán, F. J., Azañón, J.M. y García-Cortés, A. (2013). El colapso gravitacional del frente orogénico a lpino en el Dominio Subbético durante el Mioceno medio-superior: El Complejo Extensional Subbético. Boletín Geológico y Minero, 124 (3): 477-504. Roldán, F.J., Azañón, J.M. y Rodríguez-Fernández, J. (2012): Desplazamiento extensional del Subbético entre las sierras de Cabra y Alta Coloma (Valdepeñas de Jaén. Zonas Externas de la Cordillera Bética). VIII Congreso Geológico de España oviedo. GEOTEMAS, V-13: 484. Roldán, F.J., Rodríguez-Fernández, J., Villalobos, M., Lastra, J., Díaz-Pinto, G., Pérez Rodríguez, A.B. (2012). Zonas: Subbético, Cuenca del Guadalquivir y Campo de Gibraltar. In GEODE. Mapa Geológico Digital Continuo de España. Sistema de Información Geológica Continua: SIGECO. IGME. Editor Navas, J. Disponible en: http://cuarzo.igme.es/sigeco.default.htm
Ma, Xiao-Xin; Zhu, Jun-Quan; Zhou, Hong; Yang, Wan-Xi
2012-02-01
The egg envelope is an essential structure occurring during oogenesis. It plays an important role during the process of fertilization in the large yellow croaker Pseudosciaena crocea. Elucidation of egg envelope formation helps us to understand fertilization mechanisms in teleosts. In the present work, we studied the formation of egg envelope in P. crocea by light microscopy, as well as by transmission and scanning electron microscopy. Four layers exist outside the oocyte plasmalemma, i.e., theca cell layer, basal membrane, granulosa cell layer and zona radiata. According to our observation, zona radiata is a multilaminar structure just like the same structure reported in teleosts, but the origin of this structure is a little different. Before it is formed, a peripheral space filled with different density of vesicles is the place where zona radiata is formed. Zona radiata (Z1) is secreted only by oocyte itself, it belongs to the primary envelope; zona radiata 2 (Z2) and zona radiata 3 (Z3) belong to the secondary envelope, because the two layers are formed after granulosa cells appear, and microvilli participate this process. It is very interesting that Z2 and Z3 are situated between Z1 and the granulosa cell first, but they translocate to the other side of Z1. This microanatomy difference may due to the participation of microvilli. The new finding about egg envelope formation in P. crocea will help us to do further investigation on fertilization mechanisms and will make artificial breeding possible which may contribute to the resource recovery of this species. Copyright © 2011 Elsevier Ltd. All rights reserved.
Survival of sheep demi-embryos in vivo and in vitro.
Shelton, J N; Szell, A
1988-01-01
Sheep embryos (morulae and blastocysts) were bisected either by microscalpel or by microneedle after dissolving the zona pellucida with acidified Tyrode's solution. Fourteen and 11 cryopreserved demi-embryos failed to develop when transferred to recipients or placed in culture, respectively. When fresh demi-embryos were cultured in Dulbecco's phosphate buffered saline (DPBS) plus fetal calf serum (FCS) or Whitten's medium, the survival rate was 26% compared to 68% for whole embryos (P<0.01), and there was a suggestion that the presence of a zona pellucida was beneficial to survival. When two demi-embryos each within a zona pellucida were transferred into each of 10 ewes, six of them lambed to produce a total of eight lambs, including two sets of identical twins. Of 10 ewes receiving two demi-embryos without zonae pellucidae, three lambed to produce a total of four lambs, including one set of identical twins. Of 10 ewes that each received two whole embryos, 10 lambed to produce a total of 16 lambs. There was a suggestion that the zona pellucida might enhance the survival of demi-morulae but not demi-blastocysts.
Mechanics of sperm-egg interaction at the zona pellucida.
Baltz, J M; Katz, D F; Cone, R A
1988-01-01
Mammalian sperm traverse several layers of egg vestments before fertilization can occur. The innermost vestment, the zona pellucida, is a glycoprotein shell, which captures and tethers the sperm before they penetrate it. We report here direct measurements of the force required to tether a motile human sperm as well as independent calculations of this force using flagellar beat parameters observed for sperm of several species on their homologous zonae. We have compared these sperm-generated forces with the calculated tensile strength of sperm-zona bonds, and found that a motile sperm can be tethered, at least temporarily, by a single bond. Therefore, sperm can be captured by the first bond formed and tethered permanently by a few. The sperm cannot subsequently penetrate the zona unless the bonds are first eliminated. However, premature elimination would simply allow the sperm to escape. Therefore, not only must the bonds be eliminated, but the timing of this must be regulated so that the sperm is already oriented toward the egg and beginning to penetrate as the bonds are broken. Images FIGURE 6 PMID:3224150
Sati, Leyla; Cayli, Sevil; Delpiano, Elena; Sakkas, Denny; Huszar, Gabor
2014-05-01
In mammalian species, acquisition of sperm fertilization competence is dependent on the phenomenon of sperm capacitation. One of the key elements of capacitation is protein tyrosine phosphorylation (TP) in various sperm membrane regions. In previous studies performed, the pattern of TP was examined in human sperm bound to zona pellucida of oocytes. In the present comparative study, TP patterns upon sperm binding to the zona pellucida or hyaluronic acid (HA) were investigated in spermatozoa arising from the same semen samples. Tyrosine phosphorylation, visualized by immunofluorescence, was localized within the acrosomal cap, equatorial head region, neck, and the principal piece. Tyrosine phosphorylation has increased in a time-related manner as capacitation progressed, and the phosphorylation pattern was identical within the principal piece and neck, regardless of the sperm bound to the zona pellucida or HA. Thus, the data demonstrated that the patterns of sperm activation-related TP were similar regardless of the spermatozoa bound to zona pellucida or HA. Further, sperm with incomplete development, as detected by excess cytoplasmic retention, failed to exhibit TP.
Sati, Leyla; Cayli, Sevil; Delpiano, Elena; Sakkas, Denny
2014-01-01
In mammalian species, acquisition of sperm fertilization competence is dependent on the phenomenon of sperm capacitation. One of the key elements of capacitation is protein tyrosine phosphorylation (TP) in various sperm membrane regions. In previous studies performed, the pattern of TP was examined in human sperm bound to zona pellucida of oocytes. In the present comparative study, TP patterns upon sperm binding to the zona pellucida or hyaluronic acid (HA) were investigated in spermatozoa arising from the same semen samples. Tyrosine phosphorylation, visualized by immunofluorescence, was localized within the acrosomal cap, equatorial head region, neck, and the principal piece. Tyrosine phosphorylation has increased in a time-related manner as capacitation progressed, and the phosphorylation pattern was identical within the principal piece and neck, regardless of the sperm bound to the zona pellucida or HA. Thus, the data demonstrated that the patterns of sperm activation-related TP were similar regardless of the spermatozoa bound to zona pellucida or HA. Further, sperm with incomplete development, as detected by excess cytoplasmic retention, failed to exhibit TP. PMID:24077441
Moléculas orgánicas obtenidas en simulaciones experimentales del medio interestelar.
NASA Astrophysics Data System (ADS)
Muñoz-Caro, Guillermo Manuel
Las nubes moleculares son regiones de formación de estrellas, con temperaturas cinéticas entre 10-50 K y densidades de 103-106 átomos cm-3. Su materia está formada por gas y polvo interestelar. Estas partículas de polvo están cubiertas por una fina capa de hielo, de unos 0.01 μm, que contiene H2O y a menudo CO, CO2, CH3OH y NH3. El hielo es presumiblemente irradiado por fotones ultravioleta y rayos cósmicos en las zonas poco profundas de las nubes moleculares y las regiones circunestelares. En un sistema de vacío, P ˜ 10-7 mbar, simulamos la deposición de hielo a partir de 10 K y la irradiación ultravioleta por medio de una lámpara de descarga de hidrógeno activada con microondas. La evolución del hielo se observa por medio de un espectrómetro infrarrojo. De este modo es posible determinar la composición del hielo observado en el medio interestelar y predecir la presencia de moléculas aún no detectadas en el espacio, que han sido producto del procesamiento del hielo en nuestros experimentos. También es posible calentar el sistema hasta temperatura ambiente para sublimar el hielo depositado. Cuando el hielo ha sido previamente irradiado, se observa un residuo compuesto por moléculas orgánicas complejas, algunas prebióticas, como varios ácidos carboxílicos, aminas, amidas, ésteres y en menor proporción moléculas heterocíclicas y aminoácidos. Algunas de estas moléculas podrían detectarse en estado gaseoso por medio de observaciones milimétricas y de radio. También podrían estar presentes en el polvo cometario, cuyo análisis químico está planeado por las misiones Stardust y Rosetta. Mientras tanto, nuestro grupo está llevando a cabo el análisis de partículas de polvo interplanetario (IDPs), algunas de las cuales pueden ser de origen cometario. Al igual que ocurre con los productos obtenidos por irradiación del hielo en nuestros experimentos, algunas IDPs son ricas en material orgánico que contiene oxígeno.
78 FR 50025 - Del Norte County Resource Advisory Committee
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-16
... authorized under the Secure Rural Schools and Community Self-Determination Act (Act) (Pub. L. 112-141) and... Service concerning projects and funding consistent with the Title II of the Act. The meetings are open to the public. The purpose of the meetings are to review prior year project's progress and to review and...
Effects of acute administration of ethanol on the rat adrenal cortex.
Milovanović, Tatjana; Budec, Mirela; Balint-Perić, Ljiljana; Koko, Vesna; Todorović, Vera
2003-09-01
The purpose of this study was to investigate the effect of a single dose of ethanol on rat adrenal cortex and to determine whether the estrous cycle can influence this effect of ethanol. Adult female Wistar rats showing proestrus or diestrus Day 1 (n = 12) were treated intraperitoneally with ethanol (4 g/kg body weight). Untreated (n = 15) and saline-injected (n = 14) rats were used as controls. The animals were sacrificed by decapitation 0.5 hour after ethanol administration. Stereological analysis was performed on paraffin sections of adrenal glands stained with AZAN, and the following parameters were determined: absolute volume of the zona glomerulosa, the zona fasciculata and the zona reticularis, numerical density, volume and the mean diameter of adrenocortical cells and of their nuclei, and diameter and length of capillaries. The diameter and volume of adrenocortical cells in the zona fasciculata and the zona reticularis were significantly increased by acute ethanol treatment at proestrus. In the same group of animals, a single dose of ethanol induced significant decrease in numerical density of adrenocortical cells and of their nuclei in all three zones. Increased length of capillaries of the zona fasciculata as well as enhanced level of serum corticosterone was found in ethanol-treated rats at both phases of the estrous cycle, proestrus and diestrus Day 1. The obtained results indicate that a single dose of ethanol activates adrenal cortex in female rats and that the effect is more pronounced on morphometric parameters at proestrus.
Determination of the reactivity of cytotoxic immune cells with preimplantation mouse embryos
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ewoldsen, M.A.
1987-01-01
Cytotoxic immune cells were used in an assay, MELIA (mixed embryo leukocyte interaction assay) to test the ability of the cells to kill blastocyst stage embryos. The cytotoxic immune cells generated for use in this study, cytotoxic T lymphocytes (CTLs), natural killer (NK) cells, and lymphokine activated killer (LAK) cells were shown to have phenotypic and cytolytic characteristics similar to those reported by other investigators. The lysis of the blastocysts in the MELIA was determined by measuring the inhibition of blastocoel retention and/or by the inhibition of incorporation of tritiated thymidine (/sup 3/H-TdR) into embryonic DNA. Blastocysts which possess ormore » lack their zonae pellucidae were tested to determine whether the zona pellucida plays an immunoprotective role in preimplantation development. The results indicated that CTLs only lysed embryonic cells when the zona pellucida was absent, but NK and LAK cells lysed embryonic cells whether the zona pellucida was present or absent. The results suggest that the zona pellucida may protect the preimplantation mouse embryo from lysis by CTLs but what protects the embryo from lysis by NK and LAK cells is unclear.« less
Actividad Solar Desde EL Espacio
NASA Astrophysics Data System (ADS)
Rovira, M. G.
1990-11-01
RESUMEN. Se describen los principales descubrimientos realizados por los arti+iciales con instrumentos dedicados a la observaci6n del Sol, durante los dos ultimos ciclos de su acti vi dad. La observaci6n el espacio ha permitido cubrir todas las zonas del espectro no observables desde tierra1 desde el ultravioleta hasta la radiaci6n gamma. Se hace referencia, en particular, a los resultados producidos por los dos grandes observatorios: el Skylab y el SMM. Este ultimo incluy6 un conjunto de instrumentos especialmente coordinados para observar en detalle las fulguraciones solares. Es un resumen para astr6nomos no especializados en la fisica solar, en el que se muestra que la gran riqueza del material observacional acumulado ha resuelto problemas preexistentes y, al mismo tiempo, ha abierto numerosos interrogantes a los que se buscar respuesta con la instrumentaci6n en desarrollo. Finalmente, se mencionan las caracteristicas de los proyectados para la pr6xima decada. : The main discoveries performed by artificial satellites instrumented for the observation of the Sun, during the last two cycles of its activity, are described. The space observations allowed of almost all the spectral regions which are not observable from the ground, from the ultraviolet to the gamma radiation. In particular, we ref er' to the two large solar space observatories: the Skylab and the SMM. The last one included a set 0+ coordinated instruments to observe in detail the solar flares. This is a summary for astronomers not dedicated to solar physics, where we show that the of observational material have solv# d many of the preexistent problems but, at the ame time, it opened many new questions to which the improved instrumentation will try to answer. , the characteristics of the satellites planned the next decade are mentioned. Key : SUN-ACTIVITY - SUN-CORONA - SUN-X-RAYS
Buffone, Mariano G; Zhuang, Tiangang; Ord, Teri S; Hui, Ling; Moss, Stuart B; Gerton, George L
2008-05-02
Many candidates have been proposed as zona pellucida-binding proteins. Without precluding a role for any of those candidates, we focused on mouse sperm protein ZP3R/sp56, which is localized in the acrosomal matrix. The objective of this study was to analyze the role of ZP3R/sp56 in mouse fertilization. We expressed recombinant ZP3R/sp56 as a secreted protein in HEK293 cells and purified it from serum-free, conditioned medium. In the presence of reducing agents, the recombinant ZP3R/sp56 exhibited a molecular weight similar to that observed for the native ZP3R/sp56. Reminiscent of the native protein, recombinant ZP3R/sp56 formed a high molecular weight, disulfide cross-linked oligomer consisting of six or more monomers under non-reducing conditions. Recombinant ZP3R/sp56 bound to the zona pellucida of unfertilized eggs but not to 2-cell embryos, indicating that the changes that take place in the zona pellucida at fertilization affected the interaction of this protein with the zona pellucida. The extent of in vitro fertilization was reduced in a dose-dependent manner when unfertilized eggs were preincubated with recombinant ZP3R/sp56 (74% drop at the maximum concentrations assayed). Eggs incubated with the recombinant protein showed an absence of or very few sperm in the perivitelline space, suggesting that the reduction in the fertilization rate is caused by the inhibition of sperm binding and/or penetration through the zona pellucida. These results indicate that sperm ZP3R/sp56 is important for sperm-zona interactions during fertilization and support the concept that the acrosomal matrix plays an essential role in mediating the binding of sperm to the zona pellucida.
NASA Astrophysics Data System (ADS)
Villata, M.
2017-05-01
"Banca del fare" is an ambitious project proposed by "Cultural Park Alta Langa". It is born to hand ancient knowledges down to young people, as meeting place useful to exchange the development of new construction techniques and at the same time the traditional ones. A program of educational workshops, which constitute the summer school, was organized for increasing communication among different generations. Indeed, the last local craftsmen or artisans are coming out from their employment and there is no training process to ensure the migration of knowledge to young architects. The activities of the school took place for the first time during summer of 2016 in Alta Langa, the southern part of Langhe in Piedmont. The landscape of this area is marked by small rural architectures called "ciabòts" shed all over the countryside. Artisans and students work together to recover these buildings every year. The aim of this landscape heritage's valorization is to relate the restored ciabòt into a network, in order to create a widespread hotels system. Therefore, the essay wants to present the results of "Banca del fare" and to suggest a GIS project that can gather information about numerous "ciabòt" widespread in this territory. The interaction between land development and networking process can ensure the optimal reuse of these rural architectures.
ERIC Educational Resources Information Center
Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.
This document provides statistical data on the distribution and education of teacher personnel working in Colombian elementary schools between 1940 and 1968. The statistics cover the number of men and women, public and private schools, urban and rural location, and the amount of education of teachers. (VM)
Uppangala, Shubhashree; D'Souza, Fiona; Pudakalakatti, Shivanand; Atreya, Hanudatta S; Raval, Keyur; Kalthur, Guruprasad; Adiga, Satish Kumar
2016-12-01
Laser assisted zona hatching (LAH) is a routinely used therapeutic intervention in assisted reproductive technology for patients with poor prognosis. However, results are not conclusive in demonstrating the benefits of zona hatching in improving the pregnancy rate. Recent observations on LAH induced genetic instability in animal embryos prompted us to look into the effects of laser assisted zona hatching on the human preimplantation embryo quality and metabolic uptake using high resolution nuclear magnetic resonance (NMR) technology. This experimental prospective study included fifty embryos from twenty-five patients undergoing intra cytoplasmic sperm injection. Embryo quality assessment followed by profiling of spent media for the non-invasive evaluation of metabolites was performed using NMR spectroscopy 24 hours after laser treatment and compared with that of non-treated sibling embryos. Both cell number and embryo quality on day 3 of development did not vary significantly between the two groups at 24 hours post laser treatment interval. Time lapse monitoring of the embryos for 24 hours did not reveal blastomere fragmentation adjacent to the point of laser treatment. Similarly, principal component analysis of metabolites did not demonstrate any variation across the groups. These results suggest that laser assisted zona hatching does not affect human preimplantation embryo morphology and metabolism at least until 24 hours post laser assisted zona hatching. However, studies are required to elucidate laser induced metabolic and developmental changes at extended time periods. AH: assisted hatching; ART: assisted reproductive technology; DNA: deoxy-ribo nucleic acid; LAH: laser assisted hatching; MHz: megahertz; NMR: nuclear magnetic resonance; PCA: principal component analysis; PGD: preimplantation genetic diagnosis; TLM: time lapse monitoring.
Possible mechanism of polyspermy block in human oocytes observed by time-lapse cinematography.
Mio, Yasuyuki; Iwata, Kyoko; Yumoto, Keitaro; Kai, Yoshiteru; Sargant, Haruka C; Mizoguchi, Chizuru; Ueda, Minako; Tsuchie, Yuka; Imajo, Akifumi; Iba, Yumiko; Nishikori, Kyoko
2012-09-01
To analyze the fertilization process related to polyspermy block in human oocytes using an in vitro culturing system for time-lapse cinematography. We had 122 oocytes donated for this study from couples that provided informed consent. We recorded human oocytes at 2,000 to 2,800 frames every 10 s during the fertilization process and thereafter every 2 min using a new in vitro culture system originally developed by the authors for time-lapse cinematography. We displayed 30 frames per second for analysis of the polyspermy block during fertilization. Three oocytes showed the leading and following sperm within the zona pellucida in the same microscopic field. The dynamic images obtained during the fertilization process using this new system revealed that once a leading sperm penetrated the zona pellucida and attached to the oocyte membrane, a following sperm was arrested from further penetration into the zona pellucida within 10 s. The present results strongly suggest the existence of a novel mechanism of polyspermy block that takes place at the zona pellucida immediately after fertilization. These findings are clearly different from previous mechanisms describing polyspermy block as the oocyte membrane block to sperm penetration and the zona reaction. The finding presented herein thus represents a novel discovery about the highly complicated polyspermy block mechanism occurring in human oocytes.
1982-09-01
enfermedades infecciosas en zonas colindantes con la Carretera Transamazonica en Brasil. II. Epidemiologia de las infecciones por arbovirus. Bol. Of...F.P. 1981. Programa multidisciplinario de vigilancia de las enfermedades , infecciosas en zonas colindantes con la Carretera Transamazonica en Brasil
Acceptability of an Embodied Conversational Agent-based Computer Application for Hispanic Women
Wells, Kristen J.; Vázquez-Otero, Coralia; Bredice, Marissa; Meade, Cathy D.; Chaet, Alexis; Rivera, Maria I.; Arroyo, Gloria; Proctor, Sara K.; Barnes, Laura E.
2015-01-01
There are few Spanish language interactive, technology-driven health education programs. Objectives of this feasibility study were to: 1) learn more about computer and technology usage among Hispanic women living in a rural community; and 2) evaluate acceptability of the concept of using an embodied conversational agent (ECA) computer application among this population. A survey about computer usage history and interest in computers was administered to a convenience sample of 26 women. A sample video prototype of a hospital discharge ECA was administered followed by questions to gauge opinion about the ECA. Data indicate women exhibited both a high level of computer experience and enthusiasm for the ECA. Feedback from community is essential to ensure equity in state of the art dissemination of health information. Hay algunos programas interactivos en español que usan la tecnología para educar sobre la salud. Los objetivos de este estudio fueron: 1) aprender más sobre el uso de computadoras y tecnología entre mujeres Hispanas que viven en comunidades rurales y 2) evaluar la aceptabilidad del concepto de usar un programa de computadora utilizando un agente de conversación encarnado (ECA) en esta población. Se administro una encuesta sobre el historial de uso y del interés de aprender sobre computadoras fue a 26 mujeres por muestreo de conveniencia. Un ejemplo del prototipo ECA en forma de video de un alta hospitalaria fue administrado y fue seguido por preguntas sobre la opinión que tenían del ECA. Los datos indican que las mujeres mostraron un alto nivel de experiencia con las computadoras y un alto nivel de entusiasmo sobre el ECA. La retroalimentación de la comunidad es esencial para asegurar equidad en la diseminación de información sobre la salud con tecnología de punta. PMID:26671558
NASA Astrophysics Data System (ADS)
Baume, G. L.; Vázquez, R. A.; Feinstein, A.
Se ha realizado fotometría CCD UBVI en la zona del cúmulo abierto NGC 6231, habiéndose observado 1062 estrellas hasta una magnitud V≈ 19. Esto posibilita tener una imagen clara de la parte inferior de la secuencia principal del cúmulo. Combinando nuestros datos con tipos espectrales tomados de la literatura pudimos re-derivar la ley de absorción en dirección a este cúmulo y encontrar que los valores de R muestran variaciones de estrella a estrella. La secuencia principal inferior muestra también algunos rasgos intrigantes: hay un codo notorio en V≈ 13.5 seguido por un gran ``spread'' de magnitudes a color constante entre las estrellas débiles y una inusualmente alta densidad de estrellas a lo largo de una banda que se extiende 1.5 mag encima de la ZAMS. Los cálculos indican que el número esperado de estrellas de campo en dirección al cúmulo debería ser menor que el observado. Una re-evaluación de las funciones de luminosidad y masa dentro de los límites -7.5 < MV < 1.5 mag y 2 Msolar < M arroja pendientes planas para ambas funciones, lo que parece ser típico de cúmulos muy jóvenes. Todos estos rasgos son congruentes con un escenario joven donde las estrellas en fase de contracción están arribando a la secuencia principal.
Mapa de Vulnerabilidad en Honduras
NASA Astrophysics Data System (ADS)
Sánchez, A. A.
2013-05-01
Dado que Honduras geográficamente se encuentra en una zona que esta expuesta a diferentes fenómenos sísmicos y climatológicos. Investigamos cuales son las zonas mas propensas a desastres naturales, la vulnerabilidad y el factor de resiliencia de la población de acuerdo a diferentes parámetros de estudio.
Knoebl, Iris, Michael J. Hemmer and Nancy D. Denslow. 2004. Induction of Zona Radiata Proteins and Vitellogenins in Estradiol and Nonylphenol Exposed Male Sheepshead Minnows (Cyprinodon variegatus). Mar. Environ. Res. 58(2-5):547-551. (ERL,GB X1059).
Several genes normall...
Lhx6-positive GABA-releasing neurons of the zona incerta promote sleep
Liu, Kai; Kim, Juhyun; Kim, Dong Won; Zhang, Yi Stephanie; Bao, Hechen; Denaxa, Myrto; Lim, Szu-Aun; Kim, Eileen; Liu, Chang; Wickersham, Ian R.; Pachnis, Vassilis; Hattar, Samer; Song, Juan; Brown, Solange P.; Blackshaw, Seth
2017-01-01
Multiple populations of wake-promoting neurons have been characterized in mammals, but few sleep-promoting neurons have been identified1. Wake-promoting cell types include hypocretin and GABA (γ-aminobutyric-acid)-releasing neurons of the lateral hypothalamus, which promote the transition to wakefulness from non-rapid eye movement (NREM) and rapid eye movement (REM) sleep2,3. Here we show that a subset of GABAergic neurons in the mouse ventral zona incerta, which express the LIM homeodomain factor Lhx6 and are activated by sleep pressure, both directly inhibit wake-active hypocretin and GABAergic cells in the lateral hypothalamus and receive inputs from multiple sleep–wake-regulating neurons. Conditional deletion of Lhx6 from the developing diencephalon leads to decreases in both NREM and REM sleep. Furthermore, selective activation and inhibition of Lhx6-positive neurons in the ventral zona incerta bidirectionally regulate sleep time in adult mice, in part through hypocretin-dependent mechanisms. These studies identify a GABAergic subpopulation of neurons in the ventral zona incerta that promote sleep. PMID:28847002
Patrat, Catherine; Auer, Jana; Fauque, Patricia; Leandri, Roger L; Jouannet, Pierre; Serres, Catherine
2006-01-01
Background The functions of three zona glycoproteins, ZP1, ZP2 and ZP3 during the sperm-zona pellucida (ZP) interaction are now well established in mice. The expression of an additional zona glycoprotein, ZPB/4, in humans, led us to reconsider the classical mouse model of gamete interaction. We investigated the various functions of human ZP (hZP) during the interaction of spermatozoa with fertilised and unfertilised oocytes. Results The hZP of fertilised oocytes retained their ability to bind sperm (albeit less strongly than that from unfertilised oocytes), to induce an intraspermatic calcium influx through voltage-dependent channels similar to that observed with hZP from unfertilised oocytes and to promote the acrosome reaction at a rate similar to that induced by the ZP of unfertilised oocytes (61.6 ± 6.2% vs60.7 ± 9.1% respectively). Conversely, the rate of hZP penetrated by sperm was much lower for fertilised than for unfertilised oocytes (19% vs 57% respectively, p < 0.01). We investigated the status of ZP2 in the oocytes used in the functional tests, and demonstrated that sperm binding and acrosome reaction induction, but not ZP penetration, occurred whether or not ZP2 was cleaved. Conclusion The change in ZP function induced by fertilisation could be different in human and mouse species. Our results suggest a zona blocking to polyspermy based at the sperm penetration level in humans. PMID:17147816
Florman, H M; First, N L
1988-08-01
The effects of accessory sex gland secretions on the zona pellucida-induced acrosome reaction of bovine spermatozoa were investigated. Soluble extracts of zonae pellucidae initiated exocytosis in ejaculated spermatozoa. This process had an ED50 of 20 ng/microliter zona pellucida protein and saturated at 50 ng/microliter (Florman and First, 1988. Dev. Biol. 128, 453-463). In epididymal sperm this dose-response relationship was shifted toward greater agonist concentrations by at least a factor of 10(3). Reconstitution of high potency agonist response was achieved in vitro by incubation of epididymal sperm with bovine seminal plasma. Reconstitution was dependent on the seminal plasma protein concentration. The ED50 of this process was 62 micrograms protein/10(8) sperm and saturation was observed with 124 micrograms protein/10(8) sperm. Agonist responses in reconstituted epididymal sperm and in ejaculated sperm were indistinguishable with regard to dependence on the zona pellucida protein concentration and the kinetics of induced acrosome reactions. Kinetic studies suggest that reconstitution is due to adsorption of regulatory factors from seminal plasma. In addition to the positive regulatory elements responsible for reconstituting activity, seminal plasma also contains negative regulatory elements which inhibit agonist response. These negative factors are inactivated during sperm capacitation, permitting the expression of positive regulators. Acting together, these regulatory elements could coordinate high affinity agonist response with the availability of eggs in vivo.
Interpretation of tracer tests performed in fractured rock of the Lange Bramke basin, Germany
NASA Astrophysics Data System (ADS)
Maloszewski, Piotr; Herrmann, Andreas; Zuber, Andrzej
Two multitracer tests performed in one of the major cross-fault zones of the Lange Bramke basin (Harz Mountains, Germany) confirm the dominant role of the fault zone in groundwater flow and solute transport. Tracers having different coefficients of molecular diffusion (deuterium, bromide, uranine, and eosine) yielded breakthrough curves that can only be explained by a model that couples the advective-dispersive transport in the fractures with the molecular diffusion exchange in the matrix. For the scale of the tests (maximum distance of 225m), an approximation was used in which the influence of adjacent fractures is neglected. That model yielded nearly the same rock and transport parameters for each tracer, which means that the single-fracture approximation is acceptable and that matrix diffusion plays an important role. The hydraulic conductivity of the fault zone obtained from the tracer tests is about 1.5×10-2m/s, whereas the regional hydraulic conductivity of the fractured rock mass is about 3×10-7m/s, as estimated from the tritium age and the matrix porosity of about 2%. These values show that the hydraulic conductivity along the fault is several orders of magnitude larger than that of the remaining fractured part of the aquifer, which confirms the dominant role of the fault zones as collectors of water and conductors of fast flow. Résumé Deux multitraçages ont été réalisés dans l'une des zones principales de failles du bassin de Lange Bramke (massif du Harz, Allemagne); les résultats confirment le rôle prédominant de la zone de failles pour l'écoulement souterrain et le transport de soluté. Les traceurs, possédant des coefficients de diffusion différents (deutérium, bromure, uranine et éosine), ont fourni des courbes de restitution qui ne peuvent être expliquées que par un modèle qui associe un transport advectif-dispersif dans les fractures à un échange par diffusion moléculaire dans la matrice. A l'échelle des expériences (distance maximale de 225m), l'influence des fractures adjacentes a été négligée. Ce modèle a fourni pour chaque traceur pratiquement les mêmes paramètres pour la roche et le transport, ce qui signifie que l'approximation de la fracture unique est acceptable et que la diffusion dans la matrice joue un rôle important. La conductivité hydraulique de la zone de faille fournie par les traçages est d'environ 1,5×10-2m/s, alors que la conductivité hydraulique régionale de la roche fracturée dans son ensemble est de l'ordre de 3×10-7m/s, selon l'estimation tirée des âges tritium et de la porosité de la matrice d'environ 2%. Ces valeurs montrent que la conductivité hydraulique le long de la faille est supérieure de plusieurs ordres de grandeur à celle de la partie fracturée restante de l'aquifère, ce qui confirme le rôle prédominant joué par les zones de failles comme drains de l'eau et comme axes d'écoulement rapide. Resumen Dos ensayos con múltiples trazadores realizados en una de las zonas más fracturadas de la cuenca de Lange Bramke (Montes Harz, Alemania) confirman el papel dominante de la zona de fractura en el flujo de agua subterránea y el transporte de solutos. Trazadores con distintos coeficientes de difusión molecular (deuterio, bromuro, uranina y eosina) dieron curvas de llegada que sólo pueden ser explicadas mediante un modelo que acople el transporte advectivo-dispersivo en las fracturas con la difusión en la matriz. Para la escala de los ensayos (distancia máxima de 225m), se usó como aproximación que la influencia de las fracturas adyacentes podía despreciarse. Este modelo dio lugar para cada trazador a valores muy similares de los parámetros de transporte, lo que supone que la aproximación de fractura única es aceptable y que la difusión en la matriz es un mecanismo importante. La conductividad hidráulica de la zona fracturada obtenida de los ensayos es de unos 1.5×10-2m/s, mientras que la conductividad hidráulica regional para la matriz rocosa es de unos 3×10-7m/s, valor estimado de la edad del tritio y la porosidad de la matriz es del 2%. Estos resultados indican que la conductividad hidráulica a lo largo de la fractura es varios órdenes de magnitud mayor que la correspondiente al resto de la parte fracturada del acuífero, lo que confirma el papel dominante de las fracturas como zonas conductoras preferentes de agua.
Impacts of afforestation on groundwater resources and quality
NASA Astrophysics Data System (ADS)
Allen, Alistair; Chapman, Deborah
2001-07-01
Plans to double the proportion of land under forest cover in Ireland by the year 2035 have been initiated. The plan, primarily financially driven, ignores potential environmental impacts of forestry, particularly impacts on groundwater resources and quality. Since groundwater supplies almost 25% of Ireland's total potable water, these impacts are important. Field investigations indicate that afforestation leads to a reduction in runoff by as much as 20%, mainly due to interception of rainfall by forest canopies. Clearfelling has the opposite impact. Implications are that uncoordinated forestry practices can potentially exacerbate flooding. Groundwater recharge is affected by forestry, largely due to greater uptake of soil water by trees and to increased water-holding capacity of forest soils, arising from higher organic contents. Recharge rates under forests can be reduced to one tenth that under grass or heathland. Groundwater quality may be affected by enhanced acidification and nitrification under forests, due partly to scavenging of atmospheric pollutants by forest canopies, and partly to greater deposition of highly acid leaf litter. The slower recharge rates of groundwater under forests lead to significant delays in manifestation of deterioration in groundwater quality. Résumé. Des plans sont à l'étude pour doubler la proportion du couvert forestier en Irlande d'ici à 2035. Le plan, primitivement déterminé sur une base financière, ignore les impacts environnementaux potentiels de la foresterie, et particulièrement les impacts sur les ressources en eau souterraine et leur qualité. Du fait que les eaux souterraines satisfont presque 25% du total de l'eau potable de l'Irlande, ces impacts sont importants. Les études de terrain montrent que le reboisement conduit à une réduction du ruissellement d'au moins 20%, principalement à cause d'une interception de la pluie par le couvert forestier. Les coupes ont un impact contraire. Les implications sont que des pratiques forestières non coordonnées sont susceptibles d'exacerber les crues. La recharge des nappes est affectée par la foresterie, surtout à cause de prélèvements plus importants de l'eau du sol par les arbres et à cause de la capacité accrue des sols forestiers à retenir de l'eau, conduisant à de plus fortes teneurs en matières organiques. Les taux de recharge sous les forêts peuvent être réduits d'un dixième par rapport à la prairie ou à la lande. La qualité de l'eau souterraine peut être affectée par une acidification accrue et par une nitrification sous les forêts, provoquées pour une part par une fixation des polluants atmosphériques par le couvert forestier et pour une autre part par un dépôt plus important d'une litière plus fortement acide. Les taux de recharge plus lente des nappes sous les forêts conduisent à des retards importants dans la manifestation de la détérioration de la qualité de l'eau souterraine. Resumen. Se han iniciado los planes para duplicar la proporción de terrenos reforestados en Irlanda hacia el año 2035. El plan, impulsado por fines económicos, ignora los impactos potenciales medioambientales de la silvicultura, y, en particular, los impactos a los recursos de aguas subterráneas y a su calidad. Puesto que el 25 % del agua potable en Irlanda es suministrada por medio de aguas subterráneas, dichos impactos son importantes. Las investigaciones de campo indican que la reforestación lleva a una reducción de la escorrentía de hasta un 20 %, fundamentalmente por la interceptación de la lluvia en las copas de los árboles, mientras que la deforestación tiene el impacto opuesto. Las implicaciones son tales que las prácticas forestales descoordinadas pueden aumentar enormemente el riesgo de inundaciones. También la recarga a los acuíferos se ve afectada por la reforestación, debido, sobre todo, al uso del agua del suelo por los árboles y a la mayor capacidad de retención de los suelos en zonas boscosas, al disponer de más materia orgánica. Las tasas de recarga en zonas boscosas pueden verse reducidas al 10 % de las estimadas en campos de hierba o brezales. La calidad de las aguas subterráneas en zonas boscosas puede verse afectada por procesos de acidificación y nitrificación adicionales, causados por la retención de contaminantes atmosféricos en las copas de los árboles, y, en parte, por la acumulación de hojas enormemente ácidas en descomposición. El hecho de que la tasa de recarga sea inferior en zonas boscosas causa un retardo en la detección de fenómenos de deterioro de la calidad de las aguas subterráneas.
González-Ortega, C; Cancino-Villarreal, P; Alonzo-Torres, V E; Martínez-Robles, I; Pérez-Peña, E; Gutiérrez-Gutiérrez, A M
2016-04-01
Identification of the best embryos to transfer is a key element for success in assisted reproduction. In the last decade, several morphological criteria of oocytes and embryos were evaluated with regard to their potential for predicting embryo viability. The introduction of polarization light microscopy systems has allowed the visualization of the meiotic spindle and the different layers of the zona pellucida in human oocytes on the basis of birefringence in a non-destructive way. Conflicting results have been reported regarding the predictive value in ICSI cycles. To assess the predictive ability of meiotic spindle and zona pellucida of human oocytes to implant by polarized microscopy in ICSI cycles. Prospective and observational clinical study. 903 oocytes from 94 ICSI cycles were analyzed with polarized microscopy. Meiotic spindle visualization and zona pellucida birefringence values by polarized microscopy were correlated with ICSI cycles results. Meiotic spindle visualization and birefringence values of zona pellucida decreased in a direct basis with increasing age. In patients aged over the 35 years, the percentage of a visible spindle and mean zona pellucida birefringence was lower than in younger patients. Fertilization rate were higher in oocytes with visible meiotic spindle (81.3% vs. 64%; p < 0.0001), as well as embryo quality (47.4% vs. 39%; p=0.01). Fertilization rate was higher in oocytes with positive values of birefringence (77.5 % vs. 68.5% p=0.005) with similar embryo quality. Conception cycles showed oocytes with higher mean value of zona birefringence and visible spindle vs. no-conception cycles (p<0.05). Polarized light microscopy improves oocyte selection, which significantly impacts in the development of embryos with greater implantation potential. The use of polarized light microscopy with sperm selection methods, blastocyst culture and deferred embryo transfers will contribute to transfer fewer embryos without diminishing rates of live birth and single embryo transfer will be more feasible.
Sperm Proteasomes Degrade Sperm Receptor on the Egg Zona Pellucida during Mammalian Fertilization
Zimmerman, Shawn W.; Manandhar, Gaurishankar; Yi, Young-Joo; Gupta, Satish K.; Sutovsky, Miriam; Odhiambo, John F.; Powell, Michael D.; Miller, David J.; Sutovsky, Peter
2011-01-01
Despite decades of research, the mechanism by which the fertilizing spermatozoon penetrates the mammalian vitelline membrane, the zona pellucida (ZP) remains one of the unexplained fundamental events of human/mammalian development. Evidence has been accumulating in support of the 26S proteasome as a candidate for echinoderm, ascidian and mammalian egg coat lysin. Monitoring ZP protein degradation by sperm during fertilization is nearly impossible because those few spermatozoa that penetrate the ZP leave behind a virtually untraceable residue of degraded proteins. We have overcome this hurdle by designing an experimentally consistent in vitro system in which live boar spermatozoa are co-incubated with ZP-proteins (ZPP) solubilized from porcine oocytes. Using this assay, mimicking sperm-egg interactions, we demonstrate that the sperm-borne proteasomes can degrade the sperm receptor protein ZPC. Upon coincubation with motile spermatozoa, the solubilized ZPP, which appear to be ubiquitinated, adhered to sperm acrosomal caps and induced acrosomal exocytosis/formation of the acrosomal shroud. The degradation of the sperm receptor protein ZPC was assessed by Western blotting band-densitometry and proteomics. A nearly identical pattern of sperm receptor degradation, evident already within the first 5 min of coincubation, was observed when the spermatozoa were replaced with the isolated, enzymatically active, sperm-derived proteasomes. ZPC degradation was blocked by proteasomal inhibitors and accelerated by ubiquitin-aldehyde(UBAL), a modified ubiquitin protein that stimulates proteasomal proteolysis. Such a degradation pattern of ZPC is consistent with in vitro fertilization studies, in which proteasomal inhibitors completely blocked fertilization, and UBAL increased fertilization and polyspermy rates. Preincubation of intact zona-enclosed ova with isolated active sperm proteasomes caused digestion, abrasions and loosening of the exposed zonae, and significantly reduced the fertilization/polyspermy rates after IVF, accompanied by en-mass detachment of zona bound sperm. Thus, the sperm borne 26S proteasome is a candidate zona lysin in mammals. This new paradigm has implications for contraception and assisted reproductive technologies in humans, as well as animals. PMID:21383844
ERIC Educational Resources Information Center
Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.
This document provides statistical data on the distribution and education of teaching personnel working the elementary schools of Cordoba, Colombia, between 1958 and 1967. The statistics cover the number of men and women, public and private schools, urban and rural location, and the amount of education of the teachers. For overall statistics in…
ERIC Educational Resources Information Center
Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.
This document provides statistical data on the distribution and education of teaching personnel working in the elementary schools of Cauca, Colombia, between 1958 and 1967. The statistics cover the number of men and women, public and private schools, urban and rural location, and the amount of education of the teachers. For overall statistics in…
ERIC Educational Resources Information Center
Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.
This document provides statistical data on the distribution and education of teaching personnel working in the elementary schools of Caldas, Colombia, between 1958 and 1967. The statistics cover the number of men and women, public and private schools, urban and rural location, and the amount of education of the teachers. For overall statistics in…
ERIC Educational Resources Information Center
Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.
This document provides statistical data on the distribution and education of teaching personnel working in the elementary schools of Boyaca, Colombia, between 1958 and 1967. The statistics cover the number of men and women, public and private schools, urban and rural location, and the amount of education of the teachers. For overall statistics in…
ERIC Educational Resources Information Center
Ministerio de Educacion Nacional, Bogota (Colombia). Instituto Colombiano de Pedagogia.
This document provides statistical data on the distribution and education of teaching personnel working in the elementary schools of Huila, Colombia, between 1958 and 1967. The statistics cover the number of men and women, public and private schools, urban and rural location, and the amount of education of the teachers. For overall statistics in…
Mesquite: A multi-purpose species in two locations of San Luis Potosi, Mexico
Jose Villanueva-Diaz; Augustin Hernandez-Reyna; J. Armando Ramirez-Garcia
2000-01-01
The mesquite woodland distributed in approximately 200,000 ha in Llanos de Angostura, and Pozo del Carmen, San Luis Potosi, represents a main source of firewood, construction material, honey, and forage for the rural people that inhabit part of the lowlands of the hydrological region RH26 and RH37. Firewood collection in this region averages 142 m3 /week. Most of this...
Shimpuku, Yoko; Madeni, Frida Elikana; Horiuchi, Shigeko; Leshabari, Sebalda Charles
2017-01-30
women are more likely to give birth at a health facility when their families agree with the birthplace. However, in rural areas of Tanzania, women are often marginalized from decision-making. This study predicted birthplace intention and identified factors to reduce perceptional gaps among pregnant women, husbands and family members. explanatory cross-sectional survey was conducted in three villages in North Eastern Tanzania. Participants were 138 pregnant women and their families who answered the Birth Intention Questionnaire (BIQ), measuring knowledge, attitude, perceived behavioral control, subjective norms and intention for birthplace. Descriptive analysis, ANOVA, Chi-square, and multiple linear regression was used to analyze the data. the regression model showed that knowledge, perceived behavioral control, and subjective norms predicted intention for birthplace (R2 = .28). While 81% of pregnant women thought their husbands were decision-makers for their birth, only 38% of husbands and 37% of family members agreed. Pregnant women had significantly lower scores on the item "I will prepare for childbirth with my family" compared with husbands (p < .01) and other family members (p < .001). providing evidence-based birth preparation and reducing the identified perceptual gaps may enhance women's intention to deliver at health facilities. as mulheres são mais propensas a dar à luz em um centro de saúde quando suas famílias estão de acordo com o local de nascimento. No entanto, nas áreas rurais da Tanzânia, as mulheres são muitas vezes marginalizadas do processo de decisão. Este estudo fez previsoes de intenção para o local do parto e fatores para reduzir as lacunas de percepção entre as mulheres grávidas, seus maridos e familiares identificados. estudo transversal explicativo realizado em três aldeias no nordeste da Tanzânia. Os participantes foram 138 mulheres grávidas e suas famílias que responderam ao Questionário de Intenção sobre Parto (BIQ), medindo o conhecimento, atitude, percepcão de controle comportamental, normas subjetivas e intenção para lugar de parto. Análise descritivas, ANOVA, Qui-quadrado e regressão linear múltipla foram utilizados para analisar os dados. o modelo de regressão mostrou que o conhecimento, percepcão de controle comportamental e normas subjetivas previram intenção de lugar de parto (R2 = 0,28). Enquanto 81% das mulheres grávidas pensavam que seus maridos eram os decisores para seu parto, apenas 38% dos maridos e 37% dos membros da família concordaram. As mulheres grávidas tiveram escores significativamente mais baixos sobre o item "Vou me preparar para o parto com a minha família", em comparação com os maridos (p < 0,01) e outros membros da família (p < 0,001). Proporcionar preparação para o parto baseada em evidencias e a redução das lacunas de percepção identificadas podem melhorar a intenção das mulheres para dar à luz em unidades de saúde. las mujeres son más propensas a dar a luz en un centro de salud cuando sus familias están de acuerdo con el lugar de parto. Sin embargo, en las zonas rurales de Tanzania, las mujeres son a menudo marginadas de la toma de decisiones. Este estudio predijo la intención del lugar de parto y los factores identificados para reducir la brecha de percepción entre las mujeres embarazadas, esposos y miembros de la familia. encuesta transversal explicativa llevada a cabo en tres aldeas en el noreste de Tanzania. Los participantes fueron 138 mujeres embarazadas y sus familias, que respondieron al Cuestionario sobre Intención del Parto (BIQ), que mide el conocimiento, la actitud, percepción de control del comportamiento, las normas subjetivas y la intención de lugar de parto. Se utilizaron análisis descriptivo, ANOVA, Chi-cuadrado y regresión lineal múltiple para analizar los datos. el modelo de regresión mostró que el conocimiento, la percepción de control del comportamiento, y las normas subjetivas predijeron la intencion del lugar de parto (R2 = 0,28). Mientras que el 81% de las mujeres embarazadas pensaba que sus maridos estaban encargados de tomar decisiones para el nacimiento, sólo el 38% de los esposos y el 37% de los miembros de la familia estuvieron de acuerdo. Las mujeres embarazadas tenían puntuaciones significativamente más bajas en el tema "Me prepararé para el parto con mi familia", en comparación con los maridos (p < 0,01) y otros miembros de la familia (p < 0,001). proporcionar la preparación al parto basada en la evidencia y reducir las brechas de percepción identificadas pueden mejorar intención de las mujeres a dar a luz en centros de salud.
Body mass index is not associated with sperm-zona pellucida binding ability in subfertile males.
Sermondade, Nathalie; Dupont, Charlotte; Faure, Céline; Boubaya, Marouane; Cédrin-Durnerin, Isabelle; Chavatte-Palmer, Pascale; Sifer, Christophe; Lévy, Rachel
2013-09-01
Lifestyle factors, such as weight and nutritional status may affect male fertility, including sperm fertilization ability. The objective of this retrospective study was to evaluate the association between body mass index (BMI) and sperm-zona pellucida binding ability assessed according to the zona binding (ZB) test, which has been described to be a relevant diagnostic tool for the prediction of in vitro fertilization (IVF) ability. Three hundred and six male patients from couples diagnosed with primary idiopathic or mild male factor infertility were included. Correlations between BMI and semen parameters according to ZB test indices were assessed, together with frequencies of positive and negative tests across the BMI categories. In this selected population, BMI was not related to conventional semen parameters or sperm quality assessed according to the ability of spermatozoa to bind to the zona pellucida. The previously described poor outcomes of IVF procedures in cases of male obesity could be due to other sperm defects, such as alterations of sperm capacitation or acrosome reaction. The link between male BMI and biological outcomes during IVF procedures, such as fertilization rates, should be further evaluated.
Thermal effects in laser-assisted pre-embryo zona drilling
NASA Astrophysics Data System (ADS)
Douglas-Hamilton, Diarmaid H.; Conia, Jerome D.
2001-04-01
Diode lasers ((lambda) equals 1480 nm) are used with in vitro fertilization to dissect the zone pellucida (shell) of pre- embryos. A focused laser beam is applied in vitro to form a channel or trench in the zona pellucida. The procedure is used to facilitate biopsy or as a promoter of embryo hatching. We present examples and measurements of zona pellucida ablation using animal models. In using the laser it is vital not to damage pre-embryo cells, e.g., by overheating. In order to define safe regimes we have derived some thermal side effects of zona pellucida removal. The temperature profile in the beam and vicinity is predicted as function of laser pulse duration and power. In a crossed- beam experiment a HeNe laser probe is used to detect the temperature-induced change in the refractive index of an aqueous solution, and estimate local thermal gradient. We find that the diode laser beam produces superheated water approaching 200 degree(s)C on the beam axis. Thermal histories during and following the laser pulse are given for regions in the neighborhood of the beam. We conclude that an optimum regime exists with pulse duration
Los “puntos débiles o sensibles” de los Ensayos Clínicos en niñas/os y adolescentes
Melamed, Irene N.
2017-01-01
Resumen La revisión ética de un Ensayo Clínico1 que incluye a niñas/os y adolescentes en calidad de participantes, debe centrar su mirada en aspectos relacionados con la vulnerabilidad inherente a esa etapa de la vida, condición que se nutre de elementos biológicos, emocionales, de justicia y de equidad, entre otros. Sin embargo, la visión sugerida en este caso y sin desoír las características mencionadas, es la que busca profundizar en uno de los actores del proceso de investigación: el Ensayo Clínico. El objetivo es poder determinar la presencia o no de “zonas frágiles o de puntos débiles” en su interior, los que al ser individualizados y especialmente considerados, contribuyan a mejorar la calidad de la revisión ética de las investigaciones que son llevadas a cabo en niñas/os y adolescentes. PMID:28757905
La historia orbital de Deimos y la oblicuidad de Marte
NASA Astrophysics Data System (ADS)
Brunini, A.; Yokoyama, T.
Recientemente, se ha demostrado mediante extensas integraciones numéricas, que la rotación de Marte pasó repetidamente por estados caóticos de movimiento, debido al pasaje por zonas de resonancia spin - órbita. En dichas circunstancias, la oblicuidad marciana pudo haber sufrido grandes excursiones de varias decenas de grados. Las consecuencias de dichas variaciones son de extrema importancia en el contexto de la búsqueda de manifestaciones de vida fósil en dicho planeta. El estudio de la dinámica orbital del satélite más exterior de Marte, Deimos, nos ha permitido comprobar, en el marco de las distintas teorías sobre su orígen, que la oblicuidad de Marte dificilmente pudo haber sufrido variaciones que la aparten más de 10o respecto de actual valor. Este resultado parece ser mucho más robusto que las simulaciones numéricas de Touma y Wisdom asi como las de Laskar y Robutel, lo que permite poner cotas más severas a la evolución paleoclimática de Marte.
Special Operation Forces Command and Control Structures in the Colombia Post-Conflict
2016-05-26
demobilization of the “paramilitares” during the Alvaro Uribe pesidency. On that especific case, some of the demobilized “paramilitares” turned into...of the paramilitaries during the Alvaro Uribe presidency. On that specific case, some of the demobilized paramilitaries turned into criminal bands...sector or the whole of government approach. In the rural municipalities of Colombia, like for example La Macarena, San Vicente del Caguan and La Uribe
ERIC Educational Resources Information Center
Karlsson, Fredrik; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; van Doorn, Jan
2013-01-01
Purpose: The purpose of the present study was to examine the effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) pitch characteristics of connected speech in patients with Parkinson's disease (PD). Method: The authors evaluated 16 patients preoperatively and 12 months after DBS surgery. Eight…
A Modular, Reconfigurable Surveillance UAV Architecture
2003-09-02
Una Società Galileo Avionica A Modular, Reconfigurable Surveillance UAV Architecture METEOR, Finmeccanica Group Zona Industriale di Soleschiano Via...ES) METEOR, Finmeccanica Group Zona Industriale di Soleschiano Via Mario Stoppani 21 34077 Ronchi dei Legionari (GO) ITALY 8. PERFORMING...PMSFMS RS1Backup FMS NSU Payload Control Actuators Router Router RS2 Recovery Devices Una Società Galileo Avionica • Daylight TV Camera • IR Sensor • HR
ERIC Educational Resources Information Center
Karlsson, Fredrik; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; Nordh, Erik; van Doorn, Jan
2014-01-01
Purpose: The present study aimed at comparing the effects of deep brain stimulation (DBS) treatment of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) on the proficiency in achieving oral closure and release during plosive production of people with Parkinson's disease. Method: Nineteen patients participated preoperatively and…
Dang, Wei-min; Wang, Sheng; Tian, Shi-xiu; Chen, Bing; Sun, Fei; Li, Wei; Jiao, Yan; He, Li-hua
2007-02-01
To explore the biological effects of infrasound on the polygonal cells in adrenal cortex zona fasciculation in mice. The biological effects of infrasound on the activities of 3beta hydroxysteroid dehydrogenase (3-betaHSDH) and acid phosphatase(ACP) of the polygonal cells in adrenal cortex zona fasciculate were observed when exposure to 8 and 16 Hz infrasound at 80, 90, 100, 110, 120 and 130 dB for 1 day, 7 days and 14 days or 14 days after the exposure. When exposure to 8 Hz infrasound, the enzyme activities of 3-betaHSDH increase as the sound pressure levels increase. Only when the sound pressure levels reach 130 dB, the enzyme activities began to decrease exceptionally. When exposure to 16 Hz, 80 dB infrasound, no significant difference between the treatment and control group in the activities of 3-betaHSDH could be observed, but the injury of the polygonal cells had appeared. When exposure to 16 Hz, 100 dB infrasound, the activities of 3-betaHSDH started to increase. The cell injury still existed. When exposed to 16 Hz, 120 dB infrasound, the local tissue damage represented. Fourteen days after the mice exposure to 8 Hz, 90 dB and 130 dB infrasound for 14 days continuously, the local tissue injury of the adrenal cortex zona fasciculation began to recover at certain extent, but the higher the exposure sound pressure level, the poorer the tissue recovery. The biological effects of infrasound on the polygonal cells in adrenal cortex zona fasciculation response to the frequency of the infrasound are found at certain action strength range, but this characteristic usually is covered by the severe tissue injury. When exposure to infrasound is stopped for a period of time, the local tissue injury of the adrenal cortex zona fasciculation could recovers at certain extent, but the higher the exposure sound pressure level, the more poorer the tissue recovery.
Morales, P; Vantman, D; Barros, C; Vigil, P
1991-03-01
Several techniques have been used for selecting motile spermatozoa including Percoll and albumin gradients, swim-up, and glass wool filtration. A high yield of motile spermatozoa as well as an enhancement of motility are the most desirable features of a practical method. An equally important consideration is whether or not these techniques select functionally normal spermatozoa. In this study we have compared two methods for separation of motile cells, swim-up and Percoll gradient. Normal semen samples from 12 different men were used in this study. Each sample was simultaneously processed by swim-up and Percoll gradient using modified Tyrode's medium. After the sperm concentration was adjusted to 1 x 10(7) spermatozoa/ml, the suspensions were incubated at 37 degrees C, 5% CO2 in air. In each suspension the percentage of sperm recovery, percentage of motile spermatozoa, percentage of acrosome reacted spermatozoa (either spontaneously or stimulated with human follicular fluid), percentage of zona-free hamster oocytes penetrated, and number of spermatozoa bound to the human zona pellucida were determined. The results obtained indicated that the percentage of sperm recovery was higher with the Percoll gradient than with the swim-up procedure (P less than 0.001). However, no significant differences were found between these two sperm populations in the percentage of motile cells, in the percentage of acrosome reacted spermatozoa, and in the percentage of zona-free hamster oocytes penetrated. In addition, the number of spermatozoa bound per zona pellucida was similar for spermatozoa selected by Percoll or swim-up. We conclude that there were no functional differences between the spermatozoa selected by either method.
Culture of bovine embryos on a polydimethylsiloxane (PDMS) microwell plate.
Akagi, Satoshi; Hosoe, Misa; Matsukawa, Kazutsugu; Ichikawa, Akihiko; Tanikawa, Tamio; Takahashi, Seiya
2010-08-01
We fabricated a polydimethylsiloxane (PDMS)-based microwell plate (PDMS-MP) containing 100 microwells with a rounded bottom and examined whether it can be used for culture of individual in vitro fertilized (IVF) embryos or parthenogenetically activated zona-free embryos in cattle. In Experiment 1, we examined the in vitro developmental ability of IVF embryos cultured individually on PDMS-MP. After IVF, 20 embryos were transferred into 100 microl drops on PDMS-MP and cultured individually in each well of PDMS-MP (PDMS group). After 7 days of culture, the embryos in the PDMS group developed to the blastocyst stage at the same rate of those in the control group cultured in a group of 20 embryos without PDMS-MP. There were no differences in total number of cells and the ratio of inner cell mass to total cells between the PDMS and control groups. In Experiment 2, we examined the in vitro developmental ability of parthenogenetically activated zona-free bovine embryos cultured individually on PDMS-MP. The zona-free embryos were cultured individually in each well of a PDMS-MP or in each well produced by pressing a darning needle onto the bottom of a culture dish (WOW group). After 7 days of culture, the blastocyst formation rate and cell number of blastocysts in the PDMS group did not differ from those of the zona-intact embryos in the control group. Also, there were no differences in the blastocyst formation rate and cell number of blastocysts between the WOW and PDMS groups. These results suggest that the culture system using PDMS-MP is useful for individual embryos or zona-free embryos in cattle.
Microheater as an alternative to lasers for in-vitro fertilization applications
NASA Astrophysics Data System (ADS)
Palanker, Daniel V.; Turovets, Igor; Glazer, Rima; Reubinoff, Benjamin E.; Hilman, Dalia; Lewis, Aaron
1999-06-01
During the last decade various lasers have been applied to drilling of the micrometer-sized holes in the zona pellucida of oocytes for in-vitro fertilization applications. In this paper we describe an alternative approach to laser instrumentation based on microfabricated device capable of precise drilling of uniform holes in the zona pellucida of oocytes. This device consists of a thin (1 micrometer) film microheater built on the tip of glass capillary with a diameter varying between a few to a few tens of micrometers. Duration of the pulse of heat produced by this microheater determines the spatial confinement of the heat wave in the surrounding liquid medium. We have demonstrated that gradual microdrilling of the zona pellucida can be accomplished using a series of pulses with duration of about 300 microseconds when the microheater was held in contact with the zona pellucida. Pulse energy applied to 20 micrometer tip was about 4 (mu) J. In vitro development and hatching of 127 micromanipulated embryos was compared to 103 non-drilled control embryos. The technique was found to be highly efficient in creating round, uniform, well defined holes with a smooth wall surface, matching the size of the heating source. The architecture of the surrounding zona pellucida was unaffected by the drilling, as demonstrated by scanning electron microscopy. Micromanipulated embryos presented no signs of thermal damage under light microscopy. The rate of blastocyst formation and hatching was similar in the micromanipulated and control groups. Following further testing in animal models, this methodology may be used as a cost- effective alternative to laser-based instrumentation in clinical applications such as assisted hatching and embryo biopsy.
Kovacs, K.; Horvath, E.; Singer, W.
1973-01-01
Numerous spironolactone bodies have been detected in the zona glomerulosa cells of the adrenal cortex of a 36-year-old spironolactone-treated woman whose non-tumorous right adrenal gland was removed surgically because of primary hyperaldosteronism. Electron microscopy revealed spherical laminated whorls which consisted of a central core composed of an amorphous electron-dense material surrounded by numerous smooth-walled concentric membranes. Continuous with and deriving from the endoplasmic reticulum, they were present in viable cells and were not associated with ultrastructural features indicating cellular injury. Cytoplasmic inclusions similar to spironolactone bodies can be detected in other organs after the administration of various compounds. Thus, they can be regarded as neither specific to spironolactone treatment nor exclusively inducible in the zona glomerulosa of the adrenal cortex. Images PMID:4131694
Zonta, María L; Oyhenart, Evelia E; Navone, Graciela T
2014-01-01
The aim was to analyze the socio-environmental variables associated with malnutrition and intestinal parasitoses in children from Aristóbulo del Valle, Province of Misiones (Argentina). A cross-sectional study was performed in 2,291 schoolchildren (age, 4-14 years). Body weight and height were measured and body mass index was calculated. NHANES III reference was used to estimate the nutritional status-underweight, stunting, wasting, overweight, and obesity. The parasitological analysis was performed by fecal and anal brush samples. The socio-environmental variables were surveyed using a semi-structured questionnaire. These variables were processed by categorical principal component analysis (cat-PCA). The two first axes defined four subgroups of schoolchildren: three of these were associated with urban characteristics (high, middle, and periurban), whereas the remaining subgroup was considered rural. Stunting and parasitic infections occurred mainly in the periurban group, that is the group of higher socio-environmental vulnerability. On the other hand, the highest prevalence of overweight and obesity and the lowest parasitism was observed in the high urban group. The similarity between rural and middle urban groups in stunting prevalence reveals that cities are not healthier than rural environments. On the contrary, the fact that the rural group presents the lowest prevalence of overweight reaffirms that poverty and malnutrition are progressively moving from rural to urban areas, and that rural children have still more diverse and healthy diets favored by the consumption of homemade products (i.e., orchards, animal husbandry, etc.), placing them at an earlier stage of the nutrition transition. © 2014 Wiley Periodicals, Inc.
The practical side of immunocontraception: zona proteins and wildlife.
Kirkpatrick, J F; Rowan, A; Lamberski, N; Wallace, R; Frank, K; Lyda, R
2009-12-01
With shrinking habitat, the humane control of certain wildlife populations is relevant. The contraceptive vaccine based on native porcine zona pellucida (PZP) has been applied to various wildlife populations for 20 years. Prominent efforts include wild horses, urban deer, zoo animals and African elephants, among others. This approach has been successful in managing entire populations and to date, no significant debilitating short- or long-term health effects have been documented.
Hung, Pei-hsuan; Miller, Marion G.; Meyers, Stuart A.; VandeVoort, Catherine A.
2008-01-01
Whether the main energy source for sperm motility is from oxidative phosphorylation or glycolysis has been long-debated in the field of reproductive biology. Using the rhesus monkey as a model, we examined the role of glycolysis and oxidative phosphorylation in sperm function by using alpha-chlorohydrin (ACH), a glycolysis inhibitor, and pentachlorophenol (PCP), an oxidative phosphorylation uncoupler. Sperm treated with ACH showed no change in percentage of motile sperm, although sperm motion was impaired. The ACH-treated sperm did not display either hyperactivity- or hyperactivation-associated changes in protein tyrosine phosphorylation. When treated with PCP, sperm motion parameters were affected by the highest level of PCP (200 μM); however, PCP did not cause motility impairments even after chemical activation. Sperm treated with PCP were able to display hyperactivity and tyrosine phosphorylation after chemical activation. In contrast with motility measurements, treatment with either the glycolytic inhibitor or the oxidative phosphorylation inhibitor did not affect sperm-zona binding and zona-induced acrosome reaction. The results suggest glycolysis is essential to support sperm motility, hyperactivity, and protein tyrosine phosphorylation, while energy from oxidative phosphorylation is not necessary for hyperactivated sperm motility, tyrosine phosphorylation, sperm-zona binding, and acrosome reaction in the rhesus macaque. PMID:18480469
Gil, Ana I; Lanata, Claudio F; Hartinger, Stella M; Mäusezahl, Daniel; Padilla, Beatriz; Ochoa, Theresa J; Lozada, Michelle; Pineda, Ines; Verastegui, Hector
2014-01-01
The study described in this article evaluated sources of contamination of children's food and drinking water in rural households in the highlands of Peru. Samples from children's meals, drinking water, kitchen utensils, and caregivers' and children's hands were analyzed for total coliforms and E. coli counts using Petrifilm EC. Thermotolerant coliforms in water were measured using DelAgua test kits while diarrheagenic E. coli was identified using polymerase chain reaction methods (PCR). Thermotolerant coliforms were found in 48% of all water samples. E. coli was found on 23% of hands, 16% of utensils, and 4% of meals. Kitchen cloths were the item most frequently contaminated with total coliforms (89%) and E. coli (42%). Diarrheagenic E. coli was found in 33% of drinking water, 27% of meals, and on 23% of kitchen utensils. These findings indicate a need to develop hygiene interventions that focus on specific kitchen utensils and hand washing practices, to reduce the contamination of food, water, and the kitchen environment in these rural settings.
NASA Astrophysics Data System (ADS)
Srinivasa Rao, Y.; Reddy, T. V. K.; Nayudu, P. T.
2000-09-01
In hard-rock terrain, due to the lack of primary porosity in the bedrock, joints, fault zones, and weathered zones are the sources for groundwater occurrence and movement. To study the groundwater potential in the hard-rock terrain and drought-prone area in the Niva River basin, southern Andhra Pradesh state, India, Landsat 5 photographic data were used to prepare an integrated hydrogeomorphology map. Larsson's integrated deformation model was applied to identify the various fracture systems, to pinpoint those younger tensile fracture sets that are the main groundwater reservoirs, and to understand the importance of fracture density in groundwater prospecting. N35°-55°E fractures were identified as tensile and N35°-55°W fractures as both tensile and shear in the study area. Apparently, these fractures are the youngest open fractures. Wherever N35°-55°E and N35°-55°W fracture densities are high, weathered-zone thickness is greater, water-table fluctuations are small, and well yields are high. Groundwater-potential zones were delineated and classified as very good, good to very good, moderate to good, and poor. Résumé. Dans les roches de socle, l'absence de porosité primaire dans la roche fait que les fractures, les zones de faille et les zones d'altération sont les sites où l'eau souterraine est présente et s'écoule. Pour étudier le potentiel en eau souterraine dans la région de socle sujette à la sécheresse du bassin de la rivière Niva (sud de l'État d'Andhra Pradesh, Inde), des données photographiques de Landsat 5 ont été utilisées pour préparer une carte hydro-géomorphologique. Le modèle intégré de déformation de Larssons a été mis en œuvre pour identifier les différents systèmes de fractures, pour mettre l'accent sur les ensembles de fractures en extension les plus jeunes qui constituent les principaux réservoirs d'eau souterraine, et pour comprendre l'importance de la densité de fractures pour la prospection de l'eau souterraine. Dans la région étudiée, les fractures N35°-55°E ont été identifiées comme étant en extension, et les fractures N35°-55°W comme étant à la fois en extension et en cisaillement. Ces fractures sont apparemment les fractures ouvertes les plus jeunes. Partout où la densité des fractures N35°-55°E et N35°-55°W est élevée, la zone altérée est plus épaisse, les fluctuations de la nappe sont faibles et les rendements des puits sont forts. Des zones à potentiel en eau souterraine ont ainsi été délimitées et classées en excellent, bon à très bon, assez bon et médiocre. Resumen. Las zonas de fracturación y de meteorización son las que condicionan el flujo de agua subterránea en rocas duras, debido a la falta de porosidad primaria en la matriz rocosa. Se utilizaron cinco conjuntos de datos fotográficos del satélite Landsat con el fin de preparar un mapa integrado hidrogeomorfológico de la cuenca del río Niva, al sur del estado Andhra Pradesh (India). El objetivo era estudiar el potencial de aguas subterráneas en esta región, que es propensa a períodos de sequía, en la que predominan las rocas duras. Se aplicó el modelo de deformación integrado de Larsson a la identificación de los sistemas de fracturación. El propósito era, por un lado, identificar los conjuntos de fracturas de tracción más jóvenes, que desempeñan un papel principal como reservorios de aguas subterráneas. Por otro lado, se quería comprender la importancia de la densidad de fracturación en el desarrollo de las aguas subterráneas. Se identificó una familia de fracturas de tracción con orientación N35°-55°E y otra familia N35°-55°W que contenía tanto bandas de cizalla como fracturas de tracción. Aparentemente, se trataba de las fracturas abiertas más recientes. El espesor de la zona de meteorización es grande cuando la densidad de fracturas de estas dos familias es elevada, hecho que está asociado a fluctuaciones pequeñas del nivel freático y a caudales elevados. Se estableció una clasificación de las aguas subterráneas como zona muy buena, buena-muy buena, moderadamente buena, y regular.
Possible mechanisms of mammalian immunocontraception.
Barber, M R; Fayrer-Hosken, R A
2000-03-01
Ecological and conservation programs in ecosystems around the world have experienced varied success in population management. One of the greatest problems is that human expansion has led to the shrinking of wildlife habitat and, as a result, the overpopulation of many different species has occurred. The pressures exerted by the increased number of animals has caused environmental damage. The humane and practical control of these populations has solicited the scientific community to arrive at a safe, effective, and cost-efficient means of population control. Immunocontraception using zona pellucida antigens, specifically porcine zona pellucida (pZP), has become one of the most promising population control tools in the world today, with notable successes in horses and elephants. A conundrum has risen where pZP, a single vaccine, successfully induces an immunocontraceptive effect in multiple species of mammals. This review describes the most current data pertaining to the mammalian zona pellucida and immunocontraception, and from these studies, we suggest several potential mechanisms of immunocontraception.
The behaviour of cow blastocyst in vitro: cinematographic and morphometric analysis.
Massip, A; Mulnard, J; Vanderzwalmen, P; Hanzen, C; Ectors, F
1982-01-01
The behaviour of the cow blastocyst in vitro was studied by time-lapse cinematography and analysed by morphometry. Three types of behaviour were observed: continuous expansion followed by hatching; discontinuous expansion interrupted by few contractions and followed by hatching; discontinuous expansion interrupted by several rapid contractions without hatching. This demonstrated that the pulsatile activity of the blastocyst is not a necessary condition of hatching but also that only a moderate pulsatile activity is compatible with normal hatching. The time of hatching in vitro corresponded approximately with the time of zona loss in vivo (9-10 days). Rupture of the zona occurred at any point of the trophoblast layer. Hatching by herniation through a reduced opening of the zona was occasionally observed. The behavior of the embryos from a particular animal was very similar but differences were noted between embryos from different animals. Images Fig. 3 PMID:7076563
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamazaki, T.S.; Nagahama, Y.; Iuchi, I.
1989-05-01
A glycoprotein from the liver, which shares epitopes with chorion (egg envelope or zona pellucida) glycoproteins, is present only in the spawning female fish, Oryzias latipes, under natural conditions. This spawning female-specific (SF) substance is distinct from vitellogenin but closely resembles a major glycoprotein component, ZI-3, of the inner layer (zona radiata interna) of the ovarian egg envelope with respect to some biochemical and immunochemical characteristics. Here we report that the (/sup 125/I)SF substance, injected into the abdominal cavity of the spawning female fish, was rapidly transported by the blood circulation into the ovary and incorporated into the inner layermore » of egg envelope of the growing oocytes. The result strongly suggests that the SF substance from the liver is a precursor substance of the major component, ZI-3, of the inner layer of egg envelope in the fish.« less
Bodri, Daniel; Kato, Ryutaro; Kondo, Masae; Hosomi, Naoko; Katsumata, Yoshinari; Kawachiya, Satoshi; Matsumoto, Tsunekazu
2015-05-01
To report time-lapse monitoring of human oocytes in which the damaged zona pellucida was removed, producing zona-free (ZF) oocytes that were cultured until the blastocyst stage in time-lapse incubators. Retrospective case series. Private infertility clinic. Infertile patients (n = 32) undergoing minimal ovarian stimulation or natural cycle IVF treatment between October 2012 and June 2014. Intracytoplasmic sperm injection (ICSI) fertilization of ZF oocytes, prolonged embryo culture in time-lapse incubators, elective vitrification, and subsequent single vitrified-thawed blastocyst transfer (SVBT). Rate of fertilization, cleavage and blastocyst development, live-birth rate per SVBT cycle. In spite of advanced maternal age (39 ± 4.2; range, 30-46 years), good fertilization (94%), cleavage (94%), and blastocyst development rates (38%) were reached after fertilization and culturing of ZF oocytes/embryos. All thawed ZF blastocysts survived, and up to this date seven SVBT transfers were performed, yielding three (43%) term live births with healthy newborns. Time-lapse imagery gives a unique insight into the dynamics of embryo development in ZF embryos. Moreover, our case series demonstrate that an oocyte with a damaged zona pellucida that has been removed could be successfully fertilized with ICSI, cultured until blastocyst stage in a time-lapse incubator and vitrified electively for subsequent use. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Que, Emily L.; Duncan, Francesca E.; Bayer, Amanda R.
During fertilization or chemically-induced egg activation, the mouse egg releases billions of zinc atoms in brief bursts known as ‘zinc sparks.’ The zona pellucida (ZP), a glycoprotein matrix surrounding the egg, is the first structure zinc ions encounter as they diffuse away from the plasma membrane. Following fertilization, the ZP undergoes changes described as ‘hardening’, which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. A major event in zona hardening is cleavage of ZP2 proteins by ovastacin; however, the overall physiochemical changes contributing to zona hardening are not well understood. Using x-ray fluorescence microscopy,more » transmission and scanning electron microscopy, and biological function assays, we tested the hypothesis that zinc release contributes to ZP hardening. We found that the zinc content in the ZP increases by 300% following activation and that zinc exposure modulates the architecture of the ZP matrix. Importantly, zinc-induced structural changes of the ZP have a direct biological consequence; namely, they reduce the ability of sperm to bind to the ZP. These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. Finally, this adds a previously unrecognized factor, namely zinc, to the process of ZP hardening.« less
Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy
Que, Emily L.; Duncan, Francesca E.; Bayer, Amanda R.; ...
2017-01-19
During fertilization or chemically-induced egg activation, the mouse egg releases billions of zinc atoms in brief bursts known as ‘zinc sparks.’ The zona pellucida (ZP), a glycoprotein matrix surrounding the egg, is the first structure zinc ions encounter as they diffuse away from the plasma membrane. Following fertilization, the ZP undergoes changes described as ‘hardening’, which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. A major event in zona hardening is cleavage of ZP2 proteins by ovastacin; however, the overall physiochemical changes contributing to zona hardening are not well understood. Using x-ray fluorescence microscopy,more » transmission and scanning electron microscopy, and biological function assays, we tested the hypothesis that zinc release contributes to ZP hardening. We found that the zinc content in the ZP increases by 300% following activation and that zinc exposure modulates the architecture of the ZP matrix. Importantly, zinc-induced structural changes of the ZP have a direct biological consequence; namely, they reduce the ability of sperm to bind to the ZP. These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. Finally, this adds a previously unrecognized factor, namely zinc, to the process of ZP hardening.« less
Autoradiographic visualization of the mouse egg's sperm receptor bound to sperm
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bleil, J.D.; Wassarman, P.M.
1986-04-01
The extracellular coat, or zona pellucida, of mammalian eggs contains species-specific receptors to which sperm bind as a prelude to fertilization. In mice, ZP3, one of only three zona pellucida glycoproteins, serves as sperm receptor. Acrosome-intact, but not acrosome-reacted, mouse sperm recognize and interact with specific O-linked oligosaccharides of ZP3 resulting in sperm-egg binding. Binding, in turn, causes sperm to undergo the acrosome reaction; a membrane fusion event that results in loss of plasma membrane at the anterior region of the head and exposure of inner acrosomal membrane with its associated acrosomal contents. Bound, acrosome-reacted sperm are able to penetratemore » the zona pellucida and fuse with the egg's plasma membrane (fertilization). In the present report, we examined binding of radioiodinated, purified, egg ZP3 to both acrosome intact and acrosome reacted sperm by whole-mount autoradiography. Silver grains due to bound 125I-ZP3 were found localized to the acrosomal cap region of heads of acrosome-reacted sperm. Under the same conditions, 125I-fetuin bound at only background levels to heads of both acrosome-intact and -reacted sperm, and 125I-ZP2, another zona pellucida glycoprotein, bound preferentially to acrosome-reacted sperm. These results provide visual evidence that ZP3 binds preferentially and specifically to heads of acrosome intact sperm; properties expected of the mouse egg's sperm receptor.« less
Geology and hydrogeology of the Dammam Formation in Kuwait
NASA Astrophysics Data System (ADS)
Al-Awadi, E.; Mukhopadhyay, A.; Al-Senafy, M. N.
The Dammam Formation of Middle Eocene age is one of the major aquifers containing useable brackish water in Kuwait. Apart from the paleokarst zone at the top, the Dammam Formation in Kuwait consists of 150-200m of dolomitized limestone that is subdivided into three members, on the basis of lithology and biofacies. The upper member consists of friable chalky dolomicrite and dolomite. The middle member is mainly laminated biomicrite and biodolomicrite. The lower member is nummulitic limestone with interlayered shale toward the base. Geophysical markers conform to these subdivisions. Core analyses indicate that the upper member is the most porous and permeable of the three units, as confirmed by the distribution of lost-circulation zones. The quality of water in the aquifer deteriorates toward the north and east. A potentiometric-head difference exists between the Dammam Formation and the unconformably overlying Kuwait Group; this difference is maintained by the presence of an intervening aquitard. Résumé La formation de Damman, d'âge Éocène moyen, est l'un des principaux aquifères du Koweit, contenant de l'eau saumâtre utilisable. A part dans sa partie supérieure où existe un paléokarst, la formation de Damman au Koweit est constituée par 150 à 200m de calcaires dolomitisés, divisés en trois unités sur la base de leur lithologie et de biofaciès. L'unité supérieure est formée d'une dolomicrite crayeuse et friable et d'une dolomie. L'unité médiane est pour l'essentiel une biomicrite laminée et une biodolomicrite. L'unité inférieure est un calcaire nummulitique avec des intercalations argileuses vers la base. Les marqueurs géophysiques sont conformes à ces subdivisions. Les analyses de carottes montrent que l'unité supérieure est la plus poreuse et la plus perméable des trois. La répartition des zones d'écoulement souterrain confirment ces données. La qualité de l'eau dans l'aquifère se dégrade en direction du nord et de l'est. Une différence de niveau piézométrique est observée entre la formation de Damman et le groupe de Koweit qui la recouvre en discordance; cette différence est due à la présence d'un niveau imperméable qui la maintient captive. Resumen La Formación Damman, del Eoceno Medio, es uno de los mayores acuíferos de agua salobre aprovechable en Kuwait. Además de una zona de paleokarst en la parte superior, la Formación Damman en Kuwait consiste en 150-200m de caliza dolomitizada, que se subdivide en tres zonas en función de la litología y la biofacies. La parte superior está formada por dolomicrita yesífera friable y dolomita. La parte central es básicamente biomicrita laminada y biodolomicrita. La inferior es caliza nummulítica, con intercalaciones de pizarra en la base. Los marcadores geofísicos reflejan claramente estas subdivisiones. Los análisis de testigos revelan que la parte superior es la más porosa y permeable de las tres unidades. Esto queda confirmado con la distribución de zonas de circulación perdidas. La calidad del agua en el acuífero se deteriora hacia el norte y el este. Sobre la Formación Damman, y de manera no conforme, suprayace otra formación, que se conoce como Grupo Kuwaití. Existe una diferencia de niveles piezométricos entre ambas formaciones, la cual se mantiene por la presencia de una capa semiconfinante.
Amaya-Castellanos, Maritza Alejandra; Morales-Ruan, María Del Carmen; Uribe-Carvajal, Rebeca; Jiménez-Aguilar, Alejandra; Salazar-Coronel, Araceli Apolonia; Martínez-Tapia, Brenda; Shamah-Levy, Teresa
2018-03-01
Introducción: Se implementó un modelo de capacitación en orientación alimentaria para la población beneficiaria y el personal operativo del Programa de Abasto Rural (PAR) de Diconsa, el cual es una iniciativa social de ayuda alimentaria que abastece productos básicos y complementarios, además de brindar capacitación en localidades de alta marginación en México. Objetivo: Documentar la utilización de la Metodología de Capacitación Multimedial (MCM) en el desarrollo de un esquema de capacitación sobre orientación alimentaria y su implementación en la población beneficiaria del PAR, a través de la propia estructura operativa del PAR. Metodología: El modelo se fundamenta en la MCM, integrada por cuatro elementos didácticos e indivisibles que conforman el paquete pedagógico multimedial (PPM), compuesto a su vez por tres videos y rotafolios, material impreso, prácticas y las relaciones interpersonales. Los ejes temáticos fueron: alimentación correcta para una vida saludable, alimentación materno-infantil, elecciones saludables y gasto familiar. El modelo fue replicado en cascada en los tres niveles operativos del PAR (responsables de capacitación, supervisores operativos y beneficiarios del PAR), con un componente de multiplicación horizontal, e implementado como piloto en cuatro estados de México. Resultados: Se observó un cambio positivo sobre los conocimientos en alimentación correcta en todos los niveles de capacitación, principalmente en los beneficiarios del PAR. La evaluación del proceso mostró conocimientos previos de los responsables de capacitación en los temas, buen desempeño como facilitadores, y habilidades de presentación y manejo del grupo de los supervisores operativos. A partir de las evaluaciones y del acompañamiento en la prueba piloto, fueron modificados las actividades, las estrategias y los materiales educativos del PPM. Conclusiones: La capacitación multimedial y la educación nutricional promueven procesos de cambio y desarrollo comunitario, posibles a través de la toma de conciencia y la puesta en práctica de acciones que favorecen la salud.
Quinteros, Edgar; Ribó, Alexandre; Mejía, Roberto; López, Alejandro; Belteton, Wilfredo; Comandari, Aimee; Orantes, Carlos M; Pleites, Ernesto B; Hernández, Carlos E; López, Dina L
2017-01-01
Pesticide handling in farming activities involves substantial hazards for the rural population and for the environment. In Latin America, it is estimated that the population at risk of being affected by heavy metals is over 4 million. This research describes the different types of exposure to pesticides and heavy metals in a rural population (Loma del Gallo), considering both environmental and occupational exposure. This study consists of an inspection in a former pesticide factory (QUIMAGRO), analysis of heavy metals in samples from surface and ground water in the community close to the factory, and a survey to the local population about their perceptions of pesticide exposures. Containers with 34.6 tons of chemicals improperly stored were identified in the former factory and removed by the government. Arsenic and cadmium were found in groundwater, and the highest values were 0.012 and 0.004 mg/l, respectively. These contaminants were also detected in most surface water samples, with maximum values of 0.026 and 0.0001 mg/l, respectively. Results of the survey show that of the 44 participants 42 % were farmers. Farmers used 19 different pesticide products containing 11 active ingredients. The most used active ingredients were paraquat (65 %), methamidophos (35 %), and atrazina (29 %). Eighty-two percent of the farmers did not use personal protective equipment. In addition to the pesticides used in the agriculture of the area, pesticide containers were removed from the QUIMAGRO area, but the pollution was still present at time of sampling and it is evident by the odor of the site. Surface water had the major concentration of heavy metals than the groundwater. Loma del Gallo population has been exposed to toxic pesticide from QUIMAGRO and agriculture for many years. The farmers carry out mishandling of pesticides and they not use PPE.
[Metabolic syndrome in adults from 20 to 40 years old in a rural Mexican community].
Echavarría-Pinto, Mauro; Hernández-Lomelí, Adrián; Alcocer-Gamba, Marco Antonio; Morales-Flores, Héctor; Vázquez-Mellado, Alberto
2006-01-01
Metabolic syndrome is the main health problem in Mexico. Its two principal complications (ischemic cardiopathy and type-2 diabetes) are the two main causes of death in Mexico since 2000. To describe the prevalence of the metabolic syndrome in adults from 20 to 40 years old in a Mexican rural community (Senegal de Palomas, San Juan del Río, Querétaro) using the National Cholesterol Education Program (NCEP III) definition. A descriptive study with a random sample was carried out. We present a univariate analysis with a 95% confidence interval. 73 cases were studied. The prevalence of the metabolic syndrome was 45.2% slightly higher in men (48.4%) than in women (42.8%). The prevalence of hypertension was 27.3%. The prevalence of obesity was 26.1% using the definition of the WHO and this prevalence rises up to 49.4% using the definition of the Mexican Official Norm. 90.5% of women and 93.5% of men had low HDLc. The prevalence of metabolic syndrome in adults from 20 to 40 years old in this Mexican rural community is much higher than the national mean for the same age cohort. The results show the necessity to increase the research of our rural communities in order to identify the possible causes to this problem and to create therapeutic programs for patients with metabolic syndrome.
Program of active aging in a rural Mexican community: a qualitative approach
de la Luz Martínez-Maldonado, María; Correa-Muñoz, Elsa; Mendoza-Núñez, Víctor Manuel
2007-01-01
Background Education is one of the key elements in the promotion of a thorough paradigm for active aging. The aim of this study is to analyze factors that contribute the empowerment of older adults in a rural Mexican community and, thus, promote active aging. Methods The study was conducted in a rural Mexican community (Valle del Mezquital), based on an action-research paradigm. One hundred and fifty-five elderly subjects with elementary school education participated in a formal training program promoting gerontological development and health education. Participants in turn became coordinators of mutual-help groups (gerontological nucleus) in Mexico. In-depth interviews were carried out to assess the empowerment after training for active aging. Results It was found that there was an increasing feeling of empowerment, creativity and self-fulfillment among participants. Among the main factors that positively influenced training of the elderly toward active aging were the teaching of gerontology topics themselves; besides, their motivation, the self-esteem, the increased undertaking of responsibility, the feeling of belonging to the group, and the sharing of information based on personal experience and on gerontological knowledge. Conclusion The main factors that contribute to empowerment of older adults in a rural Mexican community for participate in active aging programs are the training and teaching of gerontology topics themselves; besides, their interest, experience and involvement. PMID:17910775
Functional TASK-3-Like Channels in Mitochondria of Aldosterone-Producing Zona Glomerulosa Cells.
Yao, Junlan; McHedlishvili, David; McIntire, William E; Guagliardo, Nick A; Erisir, Alev; Coburn, Craig A; Santarelli, Vincent P; Bayliss, Douglas A; Barrett, Paula Q
2017-08-01
Ca 2+ drives aldosterone synthesis in the cytosolic and mitochondrial compartments of the adrenal zona glomerulosa cell. Membrane potential across each of these compartments regulates the amplitude of the Ca 2+ signal; yet, only plasma membrane ion channels and their role in regulating cell membrane potential have garnered investigative attention as pathological causes of human hyperaldosteronism. Previously, we reported that genetic deletion of TASK-3 channels (tandem pore domain acid-sensitive K + channels) from mice produces aldosterone excess in the absence of a change in the cell membrane potential of zona glomerulosa cells. Here, we report using yeast 2-hybrid, immunoprecipitation, and electron microscopic analyses that TASK-3 channels are resident in mitochondria, where they regulate mitochondrial morphology, mitochondrial membrane potential, and aldosterone production. This study provides proof of principle that mitochondrial K + channels, by modulating inner mitochondrial membrane morphology and mitochondrial membrane potential, have the ability to play a pathological role in aldosterone dysregulation in steroidogenic cells. © 2017 American Heart Association, Inc.
Llovet, Ignacio; Dinardi, Graciela; Canevari, Cecilia; Torabi, Nahal
2016-01-01
Chagas disease (CD) is a tropical parasitic disease largely underdiagnosed and mostly asymptomatic affecting marginalized rural populations. Argentina regularly reports acute cases of CD, mostly young individuals under 14 years old. There is a void of knowledge of health care seeking behavior in subjects experiencing a CD acute condition. Early treatment of the acute case is crucial to limit subsequent development of disease. The article explores how the health outcome of persons with acute CD may be conditioned by their health care seeking behavior. The study, with a qualitative approach, was carried out in rural areas of Santiago del Estero Province, a high risk endemic region for vector transmission of CD. Narratives of 25 in-depth interviews carried out in 2005 and 2006 are analyzed identifying patterns of health care seeking behavior followed by acute cases. Through the retrospective recall of paths for diagnoses, weaknesses of disease information, knowledge at the household level, and underperformance at the provincial health care system level are detected. The misdiagnoses were a major factor in delaying a health care response. The study results expose lost opportunities for the health care system to effectively record CD acute cases.
Dinardi, Graciela; Canevari, Cecilia; Torabi, Nahal
2016-01-01
Chagas disease (CD) is a tropical parasitic disease largely underdiagnosed and mostly asymptomatic affecting marginalized rural populations. Argentina regularly reports acute cases of CD, mostly young individuals under 14 years old. There is a void of knowledge of health care seeking behavior in subjects experiencing a CD acute condition. Early treatment of the acute case is crucial to limit subsequent development of disease. The article explores how the health outcome of persons with acute CD may be conditioned by their health care seeking behavior. The study, with a qualitative approach, was carried out in rural areas of Santiago del Estero Province, a high risk endemic region for vector transmission of CD. Narratives of 25 in-depth interviews carried out in 2005 and 2006 are analyzed identifying patterns of health care seeking behavior followed by acute cases. Through the retrospective recall of paths for diagnoses, weaknesses of disease information, knowledge at the household level, and underperformance at the provincial health care system level are detected. The misdiagnoses were a major factor in delaying a health care response. The study results expose lost opportunities for the health care system to effectively record CD acute cases. PMID:27829843
Function and culture requirements of snow leopard (Panthera uncia) spermatozoa in vitro.
Roth, T L; Howard, J G; Donoghue, A M; Swanson, W F; Wildt, D E
1994-08-01
Electroejaculates from eight snow leopards were used to determine how the motility of spermatozoa was influenced by (i) type of media (Ham's F10, PBS, human tubal fluid or RPMI-1640); (ii) holding temperature (23 degrees C versus 37 degrees C); (iii) washing of spermatozoa and (iv) a sperm metabolic enhancer, pentoxifylline. The duration of sperm motility was assessed by evaluating samples in each treatment every hour for 6 h and a sperm motility index (a value combining percentage sperm motility and rate of forward progression) calculated. Spermatozoa from the Ham's F10, PBS and PBS plus pentoxifylline treatments were also co-incubated with zona-intact, domestic cat eggs that were fixed and evaluated for spermatozoa bound to the zona pellucida, penetrating the outer and inner layers of the zona pellucida and within the perivitelline space. During the 6 h co-incubation, the sperm motility index in PBS with pentoxifylline was greater (P < 0.05) than in PBS alone which, in turn, was greater (P < 0.05) than in the other three test media. Washing the spermatozoa enhanced (P < 0.05) motility in both PBS and PBS plus pentoxifylline relative to unwashed samples, but there was no effect (P > 0.05) of holding temperature. Pentoxifylline supplementation enhanced (P < 0.05) the proportion of cat eggs with bound, but not penetrated, snow leopard spermatozoa in the inner layer of the zona pellucida, and there were no spermatozoa in the perivitelline space.(ABSTRACT TRUNCATED AT 250 WORDS)
An approach to successful freezing of demi-embryos derived from day-7 bovine embryos.
Niemann, H; Brem, G; Sacher, B; Smidt, D; Kräusslich, H
1986-04-01
The developmental capacity of frozen/thawed bisected embryos (n = 33) derived from day-7 bovine embryos was investigated and compared to ordinary embryos after freezing and thawing (n = 28) and to freshly bisected embryos (n = 19). The freezing and thawing protocol was identical for ordinary and demi-embryos. The percentage of intact embryos classified as excellent, good, or poor after thawing was 92.9 and 96.3% for ordinary and demi-embryos, respectively. Pregnancy rates of 53.8 (8 15 ), 46.2 (6 13 ), and 47.5% (9 19 ) were obtained when frozen/thawed ordinary embryos and frozen/thawed demi-embryos classified as excellent or good and sealed with an additional zona pellucida from hatched pig blastocysts or freshly bisected embryos were transferred. One pair of identical twins resulted from the transfer of frozen/thawed demi-embryos sealed with an additional zona pellucida. Transfer of four frozen/thawed demi-embryos without an additional zona pellucida led to one pregnancy. In contrast, demi-embryos derived from frozen/thawed ordinary embryos (n = 8) as well as frozen/thawed demi-embryos classified as poor (n = 6) did not result in any pregnancies although two halves were transferred per recipient. It is concluded that sealing the punctured zona pellucida improves the developmental capacity of frozen/thawed demi-embryos derived from day-7 bovine embryos, and freezing demi-embryos is more efficient compared to the splitting of frozen/thawed ordinary embryos.
Acute ethanol treatment increases level of progesterone in ovariectomized rats.
Budec, Mirela; Koko, Vesna; Milovanović, Tatjana; Balint-Perić, Ljiljana; Petković, Aleksandra
2002-04-01
To determine whether an increased level of progesterone in adult female rats after acute ethanol treatment, described previously in our study, is the result of activation of adrenal glands, we analyzed adrenal cortex morphologically and measured serum levels of corticosterone and progesterone in ovariectomized rats. In addition, a possible involvement of the opioid system in an observed phenomenon was tested. Adult female Wistar rats were ovariectomized, and 3 weeks after surgery they were treated intraperitoneally with (a) ethanol (4 g/kg), (b) naltrexone (5 mg/kg), followed by ethanol (4 g/kg) 45 min later, and (c) naltrexone (5 mg/kg), followed by saline 45 min later. Untreated and saline-injected rats were used as controls. The animals were killed 0.5 h after ethanol administration. Morphometric analysis was carried out on paraffin sections of adrenal glands, stained with hematoxylin-eosin, and the following parameters were determined: absolute volume of the zona glomerulosa, the zona fasciculata, and the zona reticularis; numerical density, volume, and the mean diameter of adrenocortical cells and of their nuclei; and mean diameter and length of capillaries. The results showed that acute ethanol treatment significantly increased absolute volume of the zona fasciculata and length of its capillaries but did not alter other stereological parameters. Also, serum levels of corticosterone and progesterone were enhanced. Pretreatment with naltrexone had no effect on ethanol-induced changes. These findings are consistent with our previous hypothesis that an ethanol-induced increase of the progesterone level in adult female rats originates from the adrenal cortex.
Regis, Manuela Ferreira; Oliveira, Luciano Machado Ferreira Tenório de; Santos, Ana Raquel Mendes Dos; Leonidio, Ameliane da Conceição Reubens; Diniz, Paula Rejane Beserra; Freitas, Clara Maria Silvestre Monteiro de
2016-01-01
To analyze the levels of physical activity and sedentary behavior in adolescents living in urban and rural areas. An epidemiological, cross-section study with quantitative design, carried out at the regional level. The sample comprised 6,234 students aged 14 to 19 years, selected using random cluster sampling. The χ2 test and binary logistic regression were used in the analysis. A total of 74.5% of adolescents lived in urban areas. After adjustment, rural residents spent less time watching television (odds ratio - OR: 0.45; 95% confidence interval - 95%CI: 0.39-0.52), using a computer and/or playing video games (OR: 0.30; 95%CI: 0.22-0.42), or sitting down (OR: 0.66; 95%CI: 0.54-0.80); chose passive leisure less often (OR: 0.83; 95%IC: 0.72-0.95) and were less likely to be classified as insufficiently active (OR: 0.88; 95%IC: 0.78-0.99) when compared to urban residents, regardless of sex or age. The fact that adolescents living in rural areas who did not work were more likely to be classified as insufficiently active (OR: 2.59; 95%CI: 2.07-3.24) emphasized the significant role of occupation in physical activity levels in this group. Adolescents living in rural areas were less exposed to the sedentary behaviors, chose more active leisure, and had higher levels of physical activity. Place of residence and occupation may play a major role in youth lifestyle. Analisar os níveis de atividade física e o comportamento sedentário em adolescentes das áreas urbanas e rurais. Estudo epidemiológico, transversal, com abordagem quantitativa e abrangência estadual, cuja amostra foi constituída por 6.234 estudantes (14 a 19 anos), selecionados por meio de uma estratégia de amostragem aleatória de conglomerados. As análises foram realizadas por meio do teste χ2 e da regressão logística binária. Na amostra, 74,5% dos adolescentes eram residentes em área urbana. Após o ajuste, constatou-se que os adolescentes oriundos da área rural usavam menos televisão (odds ratio - OR: 0,45; intervalo de confiança de 95% - IC95%: 0,39-0,52), computador e/ou videogame (OR: 0,30; IC95%: 0,22-0,42), passavam menos tempo sentados (OR: 0,66; IC95%: 0,54-0,80), optaram menos pelo lazer passivo (OR: 0,83; IC95%: 0,72-0,95) e tinham menos chances de serem classificados como insuficientes ativos (OR: 0,88; IC95%: 0,78-0,99), quando comparados àqueles que residiam na área urbana, independentemente do sexo e da idade. Os adolescentes da área rural que não trabalhavam apresentaram mais chances de serem classificados como insuficientemente ativos (OR: 2,59; IC95%: 2,07-3,24), mostrando que a ocupação tinha um papel importante no nível de atividade física deste grupo. Os adolescentes residentes na área rural estiveram menos expostos aos comportamentos sedentários, optaram mais por um lazer ativo e apresentaram um melhor nível de atividade física, podendo a zona de domicílio e a ocupação influenciar no estilo de vida deles.
Viscous forces are predominant in the zona pellucida mechanical resistance
NASA Astrophysics Data System (ADS)
Papi, Massimiliano; Maiorana, Alessandro; Douet, Cécile; Maulucci, Giuseppe; Parasassi, Tiziana; Brunelli, Roberto; Goudet, Ghylène; De Spirito, Marco
2013-01-01
The zona pellucida (ZP) is a multilayer glycoprotein spherical shell surrounding mammalian eggs. The ZP's mechanical response plays a crucial role in mammalian fertilization and is a parameter commonly adopted in "in vitro fertilization" to characterize the oocytes quality. While it is assumed that ZP mechanical response is purely elastic, here we prove that dissipative forces cannot be neglected. Physiologically, this evidence implies that an increase in the spermatozoa motility can induce dramatic changes on the ZP reaction force turning ZP shell in an impenetrable barrier leading to fertility impairments.
Beliefs About Children’s Illness Among Rural Guatemalan Women.
1996-07-01
a neighboring community. "The question was: "i,Por que cree que le dio esta enfermedad a su hijo(a)?" or "Why do you think your child got sick...began: "Ya hablamos de los asientos. Ahora quisiera que me dijera ^que enfermedades del pecho o los pulmones les dan a los ninos aquf en (la communidad...Bronchitis {Bronquitisl Enfermedad de bronquios) 3 0 8 11 22 Cough (Jos) 13 20 6 6 45 Cold/pulmonary cold (catarrol catarro pulmonar) 1 3 4
Ysunza, Alberto M; Diez-Urdanivia, Silvia; Pérez-Gil, Sara E
2017-12-01
Resumen: En este artículo presentamos el proyecto de capacitación llevado a cabo en comunidades de la sierra y costa de Oaxaca, México, desde 1991, por el Centro de Capacitación Integral para Promotores Comunitarios (CECIPROC). La decisión de hacer este trabajo en Oaxaca responde a que ese estado ocupa uno de los primeros lugares de marginación y de desnutrición en menores de 5 años. El objetivo es describir un modelo de capacitación y compartir parte de las experiencias derivadas, tanto del modelo como del trabajo realizado en las distintas áreas (nutrición y alimentación, salud comunitaria, ecología y etnobotánica, y educación y organización), por promotores mujeres y hombres en sus comunidades. La experiencia obtenida en 24 años muestra la factibilidad técnica y social del proyecto en el ámbito de la salud, el reconocimiento social del proyecto del CECIPROC como un organismo civil que ha aportado alternativas como solución a la problemática de salud, el hacer suyo el proyecto por algunos promotores y los diferentes obstáculos a los que se ha enfrentado. Enfatizamos el hecho de que la situación socioeconómica y política prevaleciente en el estado de Oaxaca es una limitante para el buen desarrollo de los programas colectivos de salud, e insistimos en la necesidad de compartir nuestras experiencias para que puedan ser utilizadas en la planificación y ejecución de otros proyectos.
Pauro, Maia; García, Angelina; Nores, Rodrigo; Demarchi, Darío A
2013-10-01
Based on the analysis of the mitochondrial control region and seven biallelic markers of the Y chromosome, we investigated the genetic composition of two rural populations of southern Santiago del Estero, Argentina, that were seats in colonial times of pueblos de indios, a colonial practice that consisted of concentrating the indigenous populations in organized and accessible settlements, to facilitate Christianizing and policing. We found the Native American Y chromosome haplogroup Q1a3a in only 11% (3 of 27) of the males. Haplogroup R, common in European populations, is the most frequent haplogroup in Santiago del Estero (55%). In contrast, the persistence of Native American maternal lineages is extremely high (95%). This finding is most likely due to the low incidence in that region of the 20th century European wave of migration and to the existence of pueblos de indios from 1612 to the first decades of the 19th century. In contrast to archeological records that suggest Santiago del Estero late pre-Hispanic groups were strongly influenced by the Andean world, we did not find genetic evidence in support of significant gene fl ow. On the other hand, these populations share many mitochondrial DNA hypervariable region I (HVRI) haplotypes with other populations from the Sierras Pampeanas (particularly with Córdoba) and the Gran Chaco regions. Copyright © 2014 Wayne State University Press, Detroit, Michigan 48201-1309.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vera, T.; Abraham, S.; Oviedo, A.
The integration of the sterile insect technique (SIT) in the management of the South American fruit fly Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is a promising alternative to chemically-based control in those areas where it is sympatric with Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) or other tephritid species for which the SIT is being used. Implementation of the SIT requires the development of a cost effective mass-rearing protocol. In this work, we present demographic and quality control parameters for the A. fraterculus strain reared at the Estacion Experimental Agroindustrial Obispo Colombres, Tucuman, Argentina. Considering the rearing cage as the reproduction unit, wemore » observed that fecundity is optimal during the first 3 weeks after the onset of oviposition. Fertility was constant during this period. During 2003 and 2004, some improvements were made to the existing rearing protocol, which resulted in increased larval viability, pupal weight, and adult emergence. Current weekly egg production is 1 million per week. These eggs are used to maintain the colony and to assess quality parameters. Finally, research needs leading to improved yields and fly quality are discussed. (author) [Spanish] La integracion de la Tecnica del Insecto Esteril (TIE) en el combate integrado de la mosca Sudamericana de la fruta, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), es una alternativa interesante para reemplazar al control quimico en aquellas zonas donde esta especie es simpatrica con Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) u otros tefritidos para los que ya se utiliza la TIE. La implementacion de la TIE requiere del desarrollo de un protocolo de cria masiva que sea costo-efectivo. En este trabajo presentamos parametros demograficos y de control de calidad de la cepa criada en la Estacion Experimental Agroindustrial Obispo Colombres, Tucuman, Argentina. Considerando a la jaula de cria como unidad reproductiva, se observo que la fecundidad es optima durante las tres primeras semanas de iniciada la oviposicion y que la fertilidad se mantiene constante durante ese periodo. Durante 2003-2004 se implementaron mejoras en el protocolo de cria existente lo que resulto en un incremento de la viabilidad larvaria, del peso de pupas y del porcentaje de emergencia de adultos. La produccion actual semanal es de un millon de huevos. Los mismos son utilizados para mantener la colonia y realizar distintos estudios de calidad de esta cepa. Por ultimo, se sugieren necesidades de investigacion para alcanzar mejores rendimientos. (author)« less
Morales, P; Llanos, M; Yovich, J L; Cummins, J M; Vigil, P
1993-01-01
Several drugs have been used to stimulate human sperm motility, including 3-deoxy-adenosine, caffeine, and pentoxifylline. Pentoxifylline is an inhibitor of the phosphodiesterase and may stimulate sperm motility by increasing the intracellular levels of cAMP. In this study we have evaluated the effect of pentoxifylline in the outcome of the sperm penetration assay into zona-free hamster oocytes. Twenty-seven semen samples, obtained for diagnostic purposes, were used. After the motile sperm were selected by the swim-up technique, the samples were divided into two aliquots. One aliquot was incubated with 1 mg ml-1 of pentoxifylline at 37 degrees C, 5% CO2 for 30 min. The control aliquot was incubated with culture medium. The samples were then washed and resuspended in fresh, pentoxifylline-free medium, at a sperm concentration of 10 x 10(6) cells ml-1. One hundred microlitres of each sperm suspension was then deposited under oil and 30-40 zona-free hamster oocytes were added. After 6 h of gamete coincubation, the percentage of penetrated oocytes and the number of decondensed sperm heads were evaluated. The percentage of acrosome-reacted sperm was evaluated using the Pisum sativum lectin. The percentage of zona-free hamster oocytes penetrated was increased after pentoxifylline-treatment. The percentage of acrosome reacted sperm and the number of decondensed sperm heads per egg were not different between the control and the pentoxifylline-treated groups. The results suggest that the beneficial effect of pentoxifylline upon the sperm cells is not mediated by stimulation of the acrosome reaction.
Shi, Wei; Xu, Bo; Wu, Li-Min; Jin, Ren-Tao; Luan, Hong-Bing; Luo, Li-Hua; Zhu, Qing; Johansson, Lars; Liu, Yu-Sheng; Tong, Xian-Hong
2014-01-01
The morphological assessment of oocytes is important for embryologists to identify and select MII oocytes in IVF/ICSI cycles. Dysmorphism of oocytes decreases viability and the developmental potential of oocytes as well as the clinical pregnancy rate. Several reports have suggested that oocytes with a dark zona pellucida (DZP) correlate with the outcome of IVF treatment. However, the effect of DZP on oocyte quality, fertilization, implantation, and pregnancy outcome were not investigated in detail. In this study, a retrospective analysis was performed in 268 infertile patients with fallopian tube obstruction and/or male factor infertility. In 204 of these patients, all oocytes were surrounded by a normal zona pellucida (NZP, control group), whereas 46 patients were found to have part of their retrieved oocytes enclosed by NZP and the other by DZP (Group A). In addition, all oocytes enclosed by DZP were retrieved from 18 patients (Group B). No differences were detected between the control and group A. Compared to the control group, the rates of fertilization, good quality embryos, implantation and clinical pregnancy were significantly decreased in group B. Furthermore, mitochondria in oocytes with a DZP in both of the two study groups (A and B) were severely damaged with several ultrastructural alterations, which were associated with an increased density of the zona pellucida and vacuolization. Briefly, oocytes with a DZP affected the clinical outcome in IVF/ICSI cycles and appeared to contain more ultrastructural alterations. Thus, DZP could be used as a potential selective marker for embryologists during daily laboratory work.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jackowski, S.; Dumont, J.N.
1979-01-01
The zona pellucida and cell surface of in vivo fertilized mouse ova exhibit time dependent changes which can be detected with the scanning electron microscope. The periods of ovulation, fertilization and first cleavage in superovulated C3D2/F/sub 1/ hybrids were determined and times corresponding to G/sub 1/, S, G/sub 2/, and M were calculated. The zona of a mature unfertilized ovum has a rough texture with deep furrows; at fertilization and thereafter the zona develops a smoother, ropy and seemingly porous surface. The cell surface of the unfertilized ovum is characterized by uniform microvilli, small blebs and rounded, mound-like elevations. Aftermore » fertilization and development to G/sub 1/, the ovum loses its blebs but retains the mound-like elevations and microvilli which are now less uniform. As the ovum progresses toward S, it loses the mound-like elevations but retains microvilli in the same density as found in G/sub 1/. The ovum in G/sub 2/ exhibits smaller but more numerous microvilli which vary considerably in length. Some appear to bifurcate. The fertilized ovum developing through M and G/sub 1/ of the 2 cell stage exhibits a less dense population of relatively uniform microvilli, periodic blebs and, again, rounded elevations. The data are reminiscent of surface changes associated with the cell cycle in tissue culture cells and indicate a cyclic progression of the in vivo fertilized mouse ovum through the first cleavage division to the 2 cell stage.« less
Huszar, G; Sbracia, M; Vigue, L; Miller, D J; Shur, B D
1997-04-01
Sperm creatine phosphokinase (CK) concentrations and the synthesis of the CK-M isoform reflect normal spermiogenesis and predict maturity and fertilizing potential of ejaculated human spermatozoa. Immature spermatozoa, characterized by cytoplasmic retention and low CK-M to CK-B isoform ratios, are deficient in zona binding and fail to cause pregnancies. Because these sperm lack zona-binding ability, we examined in this study whether beta 1,4-galactosyltransferase (GalTase), a key element of sperm-zona interactions in mice, is diminished in immature human sperm. Unexpectedly, GalTase was overexpressed in immature sperm relative to mature sperm: the levels of cytoplasmic CK and plasma membrane GalTase were positively correlated (r = 0.78, p < 0.001, n = 88). Sperm populations with various levels of cellular maturity, prepared by Percoll gradients, had different CK and GalTase concentrations, but within each subpopulation the relationship between CK and GalTase was maintained (p < 0.01-0.001). GalTase activities in intact and vortex-disrupted sperm fractions were similar, showing that GalTase is present on the surface membrane of human sperm--similar to the situation in all other species assayed. The changes previously reported by our laboratory in zona-binding ability and lipid peroxidation rates (which occur simultaneously with cytoplasmic extrusion), decline in CK activity, and increased expression of the CK-M isoform are suggestive of a remodeling of the sperm surface concomitant with cytoplasmic maturation. The changes reported here in GalTase expression on the surface of maturing spermatozoa prove this hypothesis.
Liu, Ying-Lei; Chen, Ying; Zhou, Cheng-Jie; Wu, Sha-Na; Shen, Jiang-Peng; Liang, Cheng-Guang
2014-01-01
To improve the outcome of assisted reproductive technology (ART) for patients with ovulation problems, it is necessary to retrieve and select germinal vesicle (GV) stage oocytes with high developmental potential. Oocytes with high developmental potential are characterized by their ability to undergo proper maturation, fertilization, and embryo development. In this study, we analyzed morphological traits of GV stage mouse oocytes, including cumulus cell layer thickness, zona pellucida thickness, and perivitelline space width. Then, we assessed the corresponding developmental potential of each of these oocytes and found that it varies across the range measured for each morphological trait. Furthermore, by manipulating these morphological traits in vitro, we were able to determine the influence of morphological variation on oocyte developmental potential. Manually altering the thickness of the cumulus layer showed strong effects on the fertilization and embryo development potentials of oocytes, whereas manipulation of zona pellucida thickness effected the oocyte maturation potential. Our results provide a systematic detailed method for selecting GV stage oocytes based on a morphological assessment approach that would benefit for several downstream ART applications. PMID:25144310
Scheme for development of monitoring networks for springs in Bavaria, Germany
NASA Astrophysics Data System (ADS)
Bender, Steffen; Einsiedl, Florian; Wohnlich, Stefan
2001-03-01
The present groundwater monitoring network in Bavaria consists mostly of wells and only a small number of natural groundwater springs, all of which are analyzed for mainly the common physical and chemical constituents in groundwater. In order to develop a long-term groundwater management plan for all the groundwater resources of Bavaria, the Bavarian State Office for Water Management intends to establish a separate spring-monitoring network throughout the 11 groundwater provinces of the state. As a first step, significant physicochemical parameters that show considerable annual fluctuation (after monitoring 1-3 years) were determined at 21 springs or spring systems to create a basic data set to guide future monitoring. A selection procedure was developed around four parameters: (1) geological units, which includes the principal aquifers; (2) rate of spring discharge; (3) land utilization within a catchment; and (4) approximate size of the subterranean catchment. However, in the initial phase of the study, only the first three parameters were investigated. These parameters established a matrix for evaluating each groundwater region of Bavaria to aid in the selection of additional springs for the proposed monitoring network. Résumé. Le réseau actuel de surveillance des eaux souterraines en Bavière consiste surtout en des puits avec seulement un petit nombre de sources, tous analysés pour l'essentiel pour les composants courants physiques et chimiques des eaux souterraines. Afin de développer un plan de gestion à long terme des eaux souterraines de la Bavière, l'Office bavarois pour la gestion de l'eau cherche à mettre en place un réseau séparé de surveillance des sources dans les onze provinces hydrogéologiques du lander. Dans un premier temps, les paramètres physico-chimiques significatifs qui présentent des variations annuelles considérables, après 1 à 3 ans de surveillance, ont été déterminés à 21 sources ou groupes de sources pour constituer un jeu de données de base pour guider la future surveillance. Une procédure de sélection a été développée autour de quatre paramètres: (1) les unités géologiques, comprenant les principaux aquifères, (2) le débit des sources, (3) l'occupation du sol dans le bassin, et (4) la dimension approximative du bassin d'alimentation souterrain. Toutefois, dans la phase initiale de l'étude, seuls les trois premiers paramètres ont été étudiés. Ces paramètres constituent une matrice d'évaluation de chaque région hydrogéologique de Bavière pour aider à la sélection de sources supplémentaires destinées au réseau de surveillance proposé. Resumen. La red de muestreo actual de aguas subterráneas en Bavaria (Alemania) está formada sobre todo por pozos, mientras que apenas hay unos pocos manantiales naturales. Los análisis incluyen, principalmente, los parámetros físico-químicos habituales. Con el objeto de desarrollar un plan de gestión de las aguas subterráneas en Bavaria a largo plazo, el Consejo del Estado para la Gestión del Agua pretende establecer una red de muestreo de manantiales diferenciada en las once regiones en que se divide el estado desde el punto de vista de las aguas subterráneas. Como primer paso, se determinaron los parámetros físico-químicos significativos que mostraban una fluctuación anual considerable (tras un muestreo de 1 a 3 años), con la finalidad de crear una base de datos elemental que canalizara los muestreos futuros. Se desarrolló un procedimiento de selección con base en cuatro parámetros: (1) unidades geológicas y acuíferos principales; (2) caudal del manantial; (3) uso del suelo dentro de la cuenca; y (4) tamaño aproximado de la zona de captación subterránea. Sin embargo, sólo se investigaron los tres primeros parámetros durante la fase inicial del estudio. Con ellos, se estableció una matriz para evaluar cada zona acuífera dentro de Bavaria y ayudar en la inclusión de otros manantiales en la red de muestro propuesta.
Checiu, M; Schlechta, B; Checiu, I; Sandor, S
1990-01-01
After briefly presenting the main historical data of in vitro culture of preimplantation mouse embryos and their filming, the first own observations on normal preimplantation development made by using microcinematography are presented: development from two-cell to eight-cell embryos; compaction and cavitation. The timing and the duration of various developmental events were recorded. Own observations were compared with previous cinematographic data reported by other authors. Some processes needing further investigations are evidenced: rotation within the zona pellucida, penetration of cytoplasmic emissions through the zona, contraction and reexpansion.
Romero, Damian G; Zhou, Ming Yi; Yanes, Licy L; Plonczynski, Maria W; Washington, Tanganika R; Gomez-Sanchez, Celso E; Gomez-Sanchez, Elise P
2007-08-01
Regulators of G-protein signaling (RGS proteins) interact with Galpha subunits of heterotrimeric G-proteins, accelerating the rate of GTP hydrolysis and finalizing the intracellular signaling triggered by the G-protein-coupled receptor (GPCR)-ligand interaction. Angiotensin II (Ang II) interacts with its GPCR in adrenal zona glomerulosa cells and triggers a cascade of intracellular signals that regulates steroidogenesis and proliferation. On screening for adrenal zona glomerulosa-specific genes, we found that RGS4 was exclusively localized in the zona glomerulosa of the rat adrenal cortex. We studied RGS4 expression and regulation in the rat adrenal gland, including the signaling pathways involved, as well as the role of RGS4 in steroidogenesis in human adrenocortical H295R cells. We reported that RGS4 mRNA expression in the rat adrenal gland was restricted to the adrenal zonal glomerulosa and upregulated by low-salt diet and Ang II infusion in rat adrenal glands in vivo. In H295R cells, Ang II caused a rapid and transient increase in RGS4 mRNA levels mediated by the calcium/calmodulin/calmodulin-dependent protein kinase and protein kinase C pathways. RGS4 overexpression by retroviral infection in H295R cells decreased Ang II-stimulated aldosterone secretion. In reporter assays, RGS4 decreased Ang II-mediated aldosterone synthase upregulation. In summary, RGS4 is an adrenal gland zona glomerulosa-specific gene that is upregulated by aldosterone secretagogues, in vivo and in vitro, and functions as a negative feedback of Ang II-triggered intracellular signaling. Alterations in RGS4 expression levels or functions may be involved in deregulations of Ang II signaling and abnormal aldosterone secretion.
Immune-endocrine interactions in the mammalian adrenal gland: facts and hypotheses.
Nussdorfer, G G; Mazzocchi, G
1998-01-01
Several cytokines, which are the major mediators of the inflammatory responses, are well-known to stimulate the hypothalamopituitary corticotropin-releasing hormone (CRH)/adrenocorticotropic hormone (ACTH) system, thereby evoking secretory responses by the adrenal cortex. Many of these cytokines, including interleukin-1 (IL-1), IL-2, IL-6, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (INF-gamma) are synthesized in the adrenal gland by both parenchymal cells and resident macrophages, and the release of some of them (e.g., IL-6 and TNF-alpha) is regulated by the main agonists of steroid hormone secretion (e.g., ACTH and angiotensin-II) and bacterial endotoxins. Adrenocortical and adrenomedullary cells are provided with specific receptors for IL-1, IL-2, and IL-6. IL-1 and TNF-alpha directly inhibit aldosterone secretion of zona glomerulosa cells, whereas IL-6 enhances it. IL-2, IL-3, IL-6, and INF-alpha are able to directly stimulate glucocorticoid production by zona fasciculata and zona reticularis cells, whereas IL-1 exerts an analogous effect through an indirect mechanism involving the stimulation of catecholamine release by chromaffin cells and/or the activation of the intramedullary CRH/ACTH system; again, TNF-alpha depresses glucocorticoid synthesis. IL-6 raises androgen secretion by inner adrenocortical layers. IL-1 enhances the proliferation of adrenocortical cells, and findings suggest that cytokines may control the apoptotic deletion of senescent zona reticularis cells. The relevance of the intraadrenal cytokine system in the fine-tuning of the secretion and growth of the adrenal cortex under normal conditions remains to be explored. However, indirect proof is available that local immune-endocrine interactions may play an important role in modulating adrenal responses to inflammatory and immune challenges and stresses.
Ratio of inner cell mass and trophoblastic cells in demi- and intact pig embryos.
Tao, T; Reichelt, B; Niemann, H
1995-07-01
Pig morulae, early blastocysts and blastocysts were microsurgically bisected to produce zona-free demi-embryos or remained nonbisected with or without zona pellucida, and the presence of inner cell mass cells was determined using a differential fluorochrome staining technique. After 24 h of in vitro culture, all demi-embryos were classified into three categories, based on morphological criteria: 1, excellent; 2, fair; and 3, degenerated. The average number of total cells and inner cell mass cells in intact embryos cultured without zona pellucida for 24 h was higher (P < 0.05) than that for those with zona pellucida in morulae and early blastocysts. The percentage of demi-embryos without inner cell mass cells in these different morphological categories was 18.7%, 22.2% and 29.8% for morulae, respectively; 3.8%, 16.7% and 30.8% for early blastocysts, respectively; and 3.7%, 32.0% and 36.4% for blastocysts, respectively. The percentage of demi-embryos without inner cell mass cells was lower (P < 0.01) in demi-embryos classified in category 1 compared with category 3 in early blastocysts and in category 1 compared with categories 2 and 3 in blastocysts. Significant differences in the total number of cells and the number of inner cell mass cells were apparent among the three morphological categories of demi-embryos derived from morulae, early blastocysts and blastocysts. The ratio of total cells to inner cell mass cells was similar among intact pig embryos and the different morphological categories of demi-embryos derived from morulae, early blastocysts and blastocysts, with the exception of that between demi-blastocysts of category 1 and the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Navarro-González, Inmaculada; Ros, Gaspar; Martínez-García, Brígida; Rodríguez-Tadeo, Alejandra; Periago, M Jesús
2016-07-19
Introducción y objetivos: la evolución que ha experimentado en los últimos años la sociedad española ha originado una serie de cambios sociológicos y/o culturales que afectan claramente a los hábitos y preferencias alimentarias. El objetivo del presente trabajo ha sido evaluar la adherencia a la dieta mediterránea (DM) de la población universitaria en la ciudad de Murcia y la calidad de su desayuno, estableciendo la relación existente entre estas dos variables entre sí, y otras variables sociológicas analizadas.Métodos: se evaluó la adherencia a la DM en una muestra de 312 estudiantes mediante el test KIDMED, cuestionario de 16 preguntas. La calidad del desayuno fue determinada en función de la ingesta de los distintos grupos de alimentos (lácteos, cereales y frutas), de forma que se establecieron las siguientes categorías de calidad: pésima, mala, regular y buena. De cada encuestado se registraron los datos personales, lugar de origen, zona geográfica y tipo de residencia, sexo, edad, titulación universitaria, curso y las variables antropométricas (peso, altura, perímetro de cintura y cadera).Resultados: la muestra estuvo formada por 238 mujeres y 74 hombres todos ellos estudiantes universitarios de distintos títulos de grado. El 7,85% de los universitarios mostró una baja adherencia a la DM, el 48,4% media y el 43,8% alta. Los estudiantes de grado en Educación Primaria mostraron una mayor adherencia media a la DM; los estudiantes de grado en Enfermería tomaron más de una ración de verdura al día; y los de Ciencia y Tecnología de los Alimentos consumían una pieza de fruta al día. Teniendo en cuenta el sexo de los participantes, el 37,8% de las mujeres tomaban más de una verdura diaria y el 91,5% desayunaba bollería industrial; mientras que el 54,1% de los hombres tomaban frutos secos (al menos 2 o 3 veces por semana) y el 74,5% desayunaba todos los días. El 1,15% de los estudiantes mostró una calidad del desayuno pésima, el 17,65% mala, el 60,65% regular y el 20,45% buena, coincidiendo la buena calidad con el consumo de fruta en esta comida. Además, se observó una asociación significativa entre el tiempo y la calidad del desayuno, ya que aquellos estudiantes que dedicaban más de diez minutos a desayunar tomaban un desayuno de buena calidad.Conclusión: en este estudio se ha visto que la calidad del desayuno está estrechamente relacionada con el grado de adherencia al patrón dietético mediterráneo.
[Validation of three screening tests used for early detection of cervical cancer].
Rodriguez-Reyes, Esperanza Rosalba; Cerda-Flores, Ricardo M; Quiñones-Pérez, Juan M; Cortés-Gutiérrez, Elva I
2008-01-01
to evaluate the validity (sensitivity, specificity, and accuracy) of three screening methods used in the early detection of the cervical carcinoma versus the histopathology diagnosis. a selected sample of 107 women attended in the Opportune Detection of Cervicouterine Cancer Program in the Hospital de Zona 46, Instituto Mexicano del Seguro Social in Durango, during the 2003 was included. The application of Papa-nicolaou, acetic acid test, and molecular detection of human papillomavirus, and histopatholgy diagnosis were performed in all the patients at the time of the gynecological exam. The detection and tipification of the human papillomavirus was performed by polymerase chain reaction (PCR) and analysis of polymorphisms of length of restriction fragments (RFLP). Histopathology diagnosis was considered the gold standard. The evaluation of the validity was carried out by the Bayesian method for diagnosis test. the positive cases for acetic acid test, Papanicolaou, and PCR were 47, 22, and 19. The accuracy values were 0.70, 0.80 and 0.99, respectively. since the molecular method showed a greater validity in the early detection of the cervical carcinoma we considered of vital importance its implementation in suitable programs of Opportune Detection of Cervicouterino Cancer Program in Mexico. However, in order to validate this conclusion, cross-sectional studies in different region of country must be carried out.
Mercado, L; Dalcero, A; Masuelli, R; Combina, M
2007-06-01
Spontaneous fermentations are still conducted by several wineries in different regions of Argentina as a common practice. Native Saccharomyces strains associated with winery equipment, grape and spontaneous fermentations of Malbec musts from "Zona Alta del Río Mendoza" region (Argentina) were investigated during 2001 and 2002 in the same cellar. Low occurrence of Saccharomyces on grapes and their limited participation during fermentation were confirmed. Strain sequential substitution during fermentation was observed. Between 30% and 60% of yeast population at the end of fermentation was coming from yeasts already present in the winery. A stable and resident Saccharomyces micro-flora in the winery was confirmed. It exhibited a dynamic behaviour during season and between years. Commercial strains were found during fermentation in different percentages, but their presence on winery equipment was low. The present work represents a first approach to winery yeast and spontaneous fermentation Saccharomyces population dynamics in an important viticultural region from Argentina that has never been characterized before. The results obtained have an important significance for the local industry, showing for the first time the real situation of the microbial ecology of alcoholic fermentation in an industrial winery from Mendoza, Argentina.
Sequential analysis of sperm functional aspects involved in fertilisation: a pilot study.
Abu, D A H; Franken, D R; Hoffman, B; Henkel, R
2012-05-01
The development of diagnostic techniques in andrology as a second level of approach to the diagnosis of male factor infertility has enthused the focus of researchers on the development of a sequential diagnostic programme for these men. Semen samples of 78 men form couples undergoing in vitro fertilisation therapy were used in the study. The semen samples were used to test sperm functional aspects known to interfere with fertilisation. These tests included semen profile, DNA integrity, apoptosis, chromatin packaging, acridin orange staining, zona binding capacity, zona-induced acrosome reaction (AR). Results were correlated with fertilisation outcome. Statistical analyses of the recorded data were carried out using a logistic regression analysis model on all sperm functional tests. A negative and significant association with the fertilisation rates was recorded for DNA damage (r = -0.56; P ≤ 0.0005). A positive significant correlation was recorded between fertilisation rates and sperm with normal DNA (r = -0.57, P ≤ 0.0004), and zona-induced AR (r = 0.33, P ≤ 0.002). Diagnostic andrology can be regarded as a mandatory part of the male factor patient's work-up schedule to assist clinicians with the most suitable therapeutic modality to follow. © 2011 Blackwell Verlag GmbH.
Kendrick, K M; Hinton, M R; Baldwin, B A
1991-05-31
In order to establish which neurotransmitters may influence the activity of zona incerta neurones in the sheep which respond selectively to the sight or ingestion of food, we have measured the release of amino acid and monoamine neurotransmitters from this region using microdialysis sampling. Co-ordinates for the placement of microdialysis probes in regions of the zona incerta where cells respond to the sight or ingestion of food were first established by making single-unit extracellular recordings. When animals were food-deprived results showed that release of gamma-aminobutyric acid (GABA) was increased in response to the sight and ingestion of food but not of aspartate, glutamate, taurine, noradrenaline, dopamine or serotonin. This release of GABA was absent when the animals were shown non-food objects or saw or ingested salt solutions. When the same animals were physiologically sodium-depleted GABA release was evoked by the sight and ingestion of salt solutions and release following the sight and ingestion of food was significantly reduced. These results provide further evidence that GABA is an important neurotransmitter in neural circuits controlling the regulation of food intake.
Puerto Rico, humedales [Puerto Rico, wetlands
Adams, D. Briane; Hefner, John M.; Dopazo, Teresa
1999-01-01
La isla de Puerto Rico, localizada al noreste del Mar Caribe y sus islas principales, Vieques, Culebra e Isla de Mona, poseen humedales en abundancia . El clima subtropical, la lluvia abundante y las complejas formas topográficas y geológicas de estas islas dan origen a los humedales, que varían desde los raros e inusuales bosques cubiertos por nubes en las tierras altas, hasta los extensos manglares, yerbas marinas y arrecifes de coral a lo largo de las costas Norte y Sur. Sin embargo, los humedales en Puerto Rico han disminuido en los últimos siglos como resultado del aumento en el desarrollo agrícola, poblacional y turístico. Algunos tipos de humedales como los bosques de palo de pollo (Pterocarpus officinalis) se han reducido a sólo unos pocos remanentes (figura 1).Biológicamente hablando, los humedales de las islas están entre las áreas más productivas. Los humedales asociados con el bosque pluvial en las tierras altas del interior de Puerto Rico contienen varias plantas raras y especies de animales que no se encuentran en otras partes de la Isla. El agua de escorrentía proveniente de los humedales en las partes altas de la Isla proveen una fuente de agua que utilizan varias ciudades para abasto público. Los humedales costeros como los mangles, los colchones de yerbas marinas y los arrecifes de coral proveen áreas para la reproducción y crianza de varios peces, crustáceos y otras especies en la cadena alimenticia (López y otros, 1988). De esta manera, los humedales costeros contribuyen a la productividad biológica de las aguas llanas del mar alrededor de las islas . Los humedales también estabilizan las costas atrapando y reteniendo sedimentos no consolidados y amortiguan la acción de las olas y de las tormentas que tienen el potencial de causar daños en la zona.El valor de los humedales de Puerto Rico para la vida silvestre está muy bien documentado . Por ejemplo, las salinas de Cabo Rojo, en la costa suroeste, proveen áreas para el descanso y la alimentación de cientos de aves migratorias en ruta entre Norte y Suramérica. Antes del drenaje de los humedales costeros para propósitos agrícolas, pantanos de agua dulce como los de la Laguna Cartagena, Laguna Guánica y Ciénaga El Anegado proveían hábitat a más de 1 00 especies de aves residentes y migratorias . Los humedales de las tierras altas del área central son el último refugio de la cotorra puertorriqueña, una especie en peligro de extinción. Aún los humedales del área metropolitana de San Juan (Laguna La Torrecilla, Torrecilla Baja, Laguna de Piñones hasta Punta Vacía Talega) proveen un hábitat excelente para la vida silvestre, mantienen criaderos de peces de alto valor económico y proveen recreación y oportunidades educativas a la población urbana.Treintiocho especies de vertebrados, moluscos y crustáceos, y 46 especies de aves, algunos raros o en peligro de extinción como la mariquita, el alcatraz, el pato dominicano, el pato silbón y la paloma cabeciblanca han sido observados en el área . También las playas asociadas con estos humedales urbanos proveen sitios de anidaje para las tortugas carey de concha y tinglar, ambas en peligro de extinción (Del Llano y otros, 1986).
Esposito, Mauro; Cavallo, Stefania; Rosato, Guido; Chiaravalle, Eugenio; Miedico, Oto; Pellicanò, Roberta; Soprano, Vittorio; Baldi, Loredana
2016-01-01
INTRODUZIONE: una vasta area compresa tra le province di Napoli e Caserta nella regione Campania ha negli ultimi anni attirato l'attenzione dei mass media a causa degli interramenti illeciti di rifiuti di varia origine nei campi o del loro abbandono lungo le strade. A tali pratiche illecite si aggiunge il fenomeno dei roghi incontrollati di questo materiale, motivo per il quale la zona è stata soprannominata "Terra dei fuochi". OBIETTIVI: ricerca di elementi in tracce presenti nei prodotti alimentari di origine vegetale prodotti nella Terra dei fuochi. DISEGNO E SETTING: piano di monitoraggio per il rilevamento dei livelli di alcuni metalli tossici ed essenziali nei vegetali coltivati in Campania nella Terra dei fuochi. La determinazione dei microelementi è stata effettuata dopo mineralizzazione della sostanza organica mediante microonde, utilizzando la spettrometria di massa a plasma induttivamente accoppiato (ICP-MS). RISULTATI: durante l'attività di monitoraggio sono stati raccolti 65 campioni di ortaggi e 49 campioni di frutta in 43 comuni rientranti nella Terra dei fuochi. Il contenuto medio di metalli tossici, cadmio e piombo nei prodotti ortofrutticoli è risultato ben lontano dai limiti massimi fissati dalla normativa europea. I valori delle concentrazioni sono significativamente inferiori rispetto a quanto riscontrato in zone ad alto impatto ambientale a causa della presenza di impianti industriali. CONCLUSIONI: la presenza di elementi tossici o potenzialmente tali nei campioni vegetali prodotti nella Terra dei fuochi è attribuibile a una varietà di fattori ambientali rilevanti (caratteristiche geologiche dell'area, inquinamento del suolo, dell'atmosfera e delle acque di irrigazione, pratiche illecite di smaltimento dei rifiuti industriali); non sembra, tuttavia, sussistere un rischio per la salute dei consumatori. Resta comunque l'allerta per la loro presenza nell'ambiente e la necessità che le attività di monitoraggio continuino.
NASA Astrophysics Data System (ADS)
Tanguy, Maliko
The objective of the thesis is to develop and evaluate useful tools and applications of Earth Observation (EO) satellite data to estimate surface fluxes in semi-arid countries. In a first part (Chapter 4), we assess the performance of a new parameterisation scheme of ground heat flux (G) to be used in remote sensing (RS) evapotranspiration (ET) estimation methods. The G-parameterisation optimized with AMMA flux data performs well and improves the sensible heat flux (H) and ET retrieved by means of the triangle method (Jiang & Islam, 2001). In a second part (Chapter 5), the triangle method is compared with ET estimated by means of a land surface model (JULES). An attempt is made to calibrate JULES using the triangle method through Monte Carlo simulations, but the two methods supply rather different results, indicating that further intercomparison tasks should be carried out to assess the performance of RS-based algorithms and land surface models in estimating the components of the land surface energy balance. Chapter 6 presents a set of operational examples for retrieving surface fluxes using RS data. The first example is the study of temporal evolution of ET-maps in Western Africa under monsoonal influence. In a second example, we apply the new scheme proposed in Chapter 4 to retrieve and analyse the long term evolution (2000-2009) of the surface energy balance components, G, H and ET at several sites of the Segura Basin (S-E Spain) using MODIS-Terra data (land surface temperature and NDVI). Temporal and spatial distribution of evapotranspiration reveals different controls on ET. (Chapter 6). In the last example, MODIS-Aqua Sea Surface Temperature (SST) is used to validate a mathematical model to retrieve surface fluxes in a Mediterranean coastal lagoon (Mar Menor, S-E Spain). El objetivo de esta tesis es de desarrollar y evaluar herramientas y aplicaciones de la teledetección para estimar flujos de superficie en zonas semiáridas. En una primera parte (Capítulo 4), se evalúa la fiabilidad de una nueva parametrización para estimar el flujo de calor en el suelo (G) con el fin de ser utilizado en métodos de estimación de la evapotranspiración (ET) usando datos de teledetección. La parametrización de G se optimiza usando datos de flujo de energía obtenido durante las campañas del proyecto AMMA, y muestra buenos resultados y una mejora de las estimaciones del flujo de calor sensible (H) y de ET cuando se utiliza conjuntamente con el método del triángulo (Jiang & Islam, 2001). En una segunda parte (Capítulo 5), el método del triángulo se compara con valores de ET estimado por un modelo de superficie terrestre (JULES). Se intenta calibrar JULES usando el método del triángulo mediante simulaciones de Monte Carlo, pero los dos métodos muestran resultados muy diferentes, indicando que se necesita tareas de comparación profundizadas para poder evaluar la eficacia de estos modelos (de superficie terrestre y basados en la teledetección) para estimar los flujos de energía a la superficie. El capítulo 6 presenta un conjunto de ejemplos de aplicaciones operacionales para estimar los flujos de superficie usando datos de teledetección. El primer ejemplo consiste en el estudio de la evolución temporal de mapas de ET en África occidental bajo la influencia del monzón africano. En el segundo ejemplo, se aplica la nueva parametrización de G descrita en el capítulo 4 para calcular y analizar la evolución a largo plazo (2000-2009) de los componentes del balance de energía a la superficie, G, H y ET, en diferentes puntos de la cuenca del río Segura (Sureste español) utilizando datos del sensor MODIS-Terra (temperatura superficial y NDVI). La distribución temporal y espacial de ET revela diferentes controles sobre ET. En el último ejemplo, datos de temperatura superficial del mar del sensor MODIS-Aqua se utilizaron para validar un modelo matemático para calcular los flujos superficiales de una laguna costera del Mediterráneo (Mar Menor en el Sureste español).
The Pliocene Yafo Formation in Israel: Hydrogeologically inert or active?
NASA Astrophysics Data System (ADS)
Avisar, D.; Rosenthal, E.; Shulman, H.; Zilberbrand, M.; Flexer, A.; Kronfeld, J.; Ben Avraham, Z.; Fleischer, L.
For several decades the ``Saqiye beds'' (later renamed Yafo Formation) underlying the Coastal Plain aquifer (Kurkar Group) aquifer of Israel, were regarded as an extremely thick, tectonically undisturbed, and absolutely impervious aquiclude. Following intensive groundwater exploitation from the overlying Kurkar Group aquifer, brackish and saline waters were locally encountered in the lower parts of this aquifer and always at the contact with the underlying Yafo Formation aquiclude. The present study revealed that this aquiclude is not a uniform and impervious rock unit, but rather an alternation of pervious and impervious strata within the Yafo Formation containing highly pressured fluids of different - mostly high - salinities. The permeable beds are at an angular unconformity and in direct contact with the overlying Kurkar Group aquifer. The Yafo Formation and the underlying and overlying rock units are dislocated by numerous fault systems, which facilitate accessibility of brines into the Kurkar Group aquifer. The mobilization of the saline fluids and their injection into the Kurkar Group aquifer could be due either to diffusion of saline fluids occurring in the permeable horizons of the Petah Tiqva Member through the clays of the Yafo Formation or to their upconing following intensive pumping in the Coastal Plain aquifer. It could have also been caused by up-dip movement of saline water as the result of overpressure generated by major accumulation of gas in the permeable horizons. Another possible mechanism could be hydraulic contact with pressurized brines up-flowing along fault zones from deep-seated Jurassic or Cretaceous reservoirs. The squeezing of saline interstitial water from the clays of the Yafo Formation into the overlying Kurkar Group aquifer, is of secondary importance for groundwater salinization (its input is comparable with salt input from rain). Depuis longtemps, les «couches de Saqiye», nommées maintenant formation de Yafo, constituant le mur de l'aquifère côtier (série de Kurkar) d'Israël, ont été considérées comme un ensemble extrêmement épais, sans déformation tectonique et totalement imperméable. À la suite de l'exploitation intensive de l'eau souterraine de l'aquifère sus-jacent de la série de Kurkar, des eaux salées et des saumures sont rencontrées occasionnellement dans les parties les plus profondes de cet aquifère et toujours au contact de l'imperméable sous-jacent de la formation de Yafo. Cette étude a révélé que cet imperméable n'est pas une unité géologique uniforme et imperméable, mais qu'il s'agit plutôt d'une alternance de couches perméables et imperméables dans la formation de Yafo contenant des fluides sous des pressions fortes avec des salinités différentes (?) et en général élevées (?). Les niveaux perméables sont en discordance angulaire et en contact direct avec l'aquifère sus-jacent de la série de Kurkar. La formation de Yafo et les unités géologiques situées dessous et dessus sont disloquées par de nombreuses systèmes de failles, qui facilitent le passage des saumures dans l'aquifère de la série de Kurkar. La mobilisation des fluides salins et leur injection dans l'aquifère de Kurkar pourraient être dues soit à la diffusion des fluides salins dans les horizons perméables du Petah Tiqva au travers des argiles de la formation de Yafo, soit leur remontée par upconing sous l'effet de pompages intensifs dans l'aquifère de la plaine côtière. Il peut aussi être causé par la remontée des eaux salines selon le pendage sous l'effet d'une surpression provoquée par une accumulation considérable de gaz dans les horizons imperméables. Un autre mécanisme possible pourrait être un contact hydraulique avec des saumures sous pression, remontant le long des zones de faille depuis des réservoirs profonds jurassiques ou crétacés. L'expulsion d'eau saline interstitielle des argiles de la formation de Yafo dans l'aquifère de Kurkar est d'importance secondaire pour la salinisation de l'eau souterraine cet apport est comparable à celui de sels par les pluies. Durante décadas, las ``Saqiyebeds'' (rebautizadas como Formación Yafo) que se sitúan bajo el acuífero Costero (Grupo Kurkar) de Israel fueron consideradas como un acuicludo extremadamente potente, tectónicamente inalterado y totalmente impermeable. Como resultado de la explotación intensiva del Grupo Kurkar, se produjo la mezcla de aguas salobres y salinas en la zona inferior de dicho acuífero y siempre en el contacto con el acuicludo subyaciente de la Formación Yafo. Este estudio reveló que el acuicludo no es una unidad rocosa uniforme e impermeable, sino que consiste en una alternancia de estratos permeables e impermeables dentro de la Formación Yafo, que contiene fluidos a alta presión de salinidades diferentes pero generalmente elevadas. Las capas permeables se hallan en inconformidad angular y en contacto directo con el acuífero superior del Grupo Kurkar. La Formación Yafo y las unidades rocosas infra- y suprayacentes están dislocadas por numerosos sistemas de fallas, lo que facilita el acceso de las salmueras al acuífero del Grupo Kurkar. Los fluidos de los horizontes permeables del Miembro Petah Tiqva a través de las arcillas de la Formación Yafo o hacia el ascenso de los domos salinos en respuesta a la extracción intensiva en el acuífero del Llano Costero. Podría también haber sido causado por el movimiento a favor del buzamiento de las aguas salinas como resultado de la sobrepresión generada por una acumulación mayor de gas en los horizontes permeables. Otro posible mecanismo podría basarse en el contacto hidráulico con salmueras presurizadas, que fluyen hacia arriba a favor de zonas de falla desde los reservorios profundos del Jurásico o del Cretácico. La extracción de agua salina intersticial desde las arcillas de la Formación Yafo hacia el acuífero superior del Grupo Kurkar es de importancia secundaria para la salinización de las aguas subterráneas, ya que su aportación es comparable a la procedente del agua de lluvia.
NASA Astrophysics Data System (ADS)
Gowing, John; Dominguez, Isabel
2013-04-01
In rural catchments of developing countries water-related diseases, due to land use patterns (agriculture and livestock), microbial pollution, inadequate sanitation systems, access to water of poor quality, and lack of institutional support are common problems which disproportionally affect poor and vulnerable people. This research aims at developing a system dynamic model to improve the understanding of the macro and micro factors that influence human health and environmental health in rural micro-catchments in Valle del Cauca, Colombia. In this catchment livelihoods for most people depend on agriculture, particularly coffee. The research uses a mediated modeling approach, in which different stakeholders in modeling sessions, develop a STELLA model that allows them to identify relations between the economic, social and environmental factors and driving forces over the performance of their system. Stakeholders jointly develop the model structure in sessions facilitated by the researcher and the data required is gathered using secondary information from the different relevant institutions and primary information from field surveys that cover socioeconomic and environmental aspects that has not been previously collected by any institution or organization (i.e. household survey, stream water survey, and drinking water survey). Representation and understanding of their system will allow the stakeholders to test the effect of different management strategies in the micro-catchment and their associated socioeconomic, environmental and human health outcomes.
Fernald, Lia C H; Hidrobo, Melissa
2011-05-01
We examined the effects of Ecuador's Bono de Desarrollo Humano (BDH)--an unconditional cash transfer program that was rolled-out using a randomized design--on health and development outcomes in very young children. Communities that were randomly assigned to the treatment group began receiving the BDH in 2004 and those randomly assigned to the comparison group began receiving benefits two years later. Families enrolled in the BDH received a monthly cash stipend ($15USD) representing an approximate 6-10% increase in household income. Participants analyzed in this study are children aged 12-35 months from treatment (n = 797) and comparison (n = 399) communities in rural and urban Ecuador. Main outcomes measured were language skills (the Fundación MacArthur Inventorio del Desarollo de Habilidades Comunicativas-Breve), height-for-age z-score, and hemoglobin concentration. Results indicate that in rural areas, being randomized to receive the BDH in very early childhood led to significantly better performance on the number of words a child was saying, and on the probability that the child was combining two or more words. There were no significant effects on language development for children in urban areas and there were no effects on height-for-age z-score or hemoglobin concentration in rural or urban areas. A limited number of potential pathways with respect to cognitive/language stimulation, health behaviors, and parenting quality were also explored. Findings indicate that compared to children in comparison areas, rural children in treatment areas were more likely to have received vitamin A or iron supplementation and have been bought a toy in the past six months. This study provides evidence for significant benefits of an unconditional cash transfer program for language development in very young children in rural areas. Copyright © 2011 Elsevier Ltd. All rights reserved.
Gutiérrez, Alfredo; Hernandez, Dagmar F; Sánchez, Jorge
2005-11-01
The abundance of freshwater snails in two rural sites of Pinar del Río, Cuba, which harbor Pseudosuccinea columella susceptible and resistant to miracidia of Fasciola hepatica was followed for one year. Susceptible snails were found in the most anthropic site (IPA) whereas the resistant population inhabited the most preserved one (El Azufre). Only two snail species coexisted with P. columella at IPA site (Physa cubensis and Tarebia granifera) while five species were found at El Azufre, including an endemic from that province (Hemisinus cubanianus). Populations of both resistant and susceptible snails showed stable densities throughout the year, although the susceptible strain attained higher abundance. The highest densities were observed in April-May 2004 for the susceptible population whereas the resistant strain attained its highest abundance in January 2004. No record of Fossaria cubensis was made and the thiarid T. granifera occurred only at low densities. One of the sampled sites (IPA) meets all the conditions for the first report of P. columella naturally infected with larvae of F. hepatica.
Osorio-Parraguez, Paulina; Espinoza, Adriana
2016-06-01
En el presente artículo se da a conocer una estrategia de intervención llevada a cabo con adultos mayores en la comuna de Paredones, sexta región de Chile, con posterioridad al terremoto y tsunami del 27 de febrero 2010 en Chile, en el contexto de una investigación sobre fortalezas y vulnerabilidades desplegadas por este grupo etario, con posterioridad a un desastre natural. Se presenta una descripción del desarrollo metodológico de la intervención y de los sustentos teóricos y conceptuales en los que se basa. Como resultado de este proceso, se propone una estrategia que trabaje a través de la identificación de las propias experiencias y fortalezas de los sujetos. De tal forma se minimizan los efectos negativos de los determinantes sociales de la salud (como la edad y el lugar de residencia) en contexto de crisis; permitiendo a los adultos mayores fortalecer sus recursos individuales y colectivos, en pro de su bienestar psicosocial. © The Author(s) 2015.
Hoyos-López, Richard; Suaza-Vasco, Juan; Rúa-Uribe, Guillermo; Uribe, Sandra; Gallego-Gómez, Juan Carlos
2016-01-01
Arboviruses belonging to the genera Flavivirus and Alphavirus were detected in mosquitoes in a rural area of San Bernardo del Viento (Córdoba, Colombia). A total of 22,180 mosquitoes were collected, sorted into 2,102 pools, and tested by generic/nested reverse transcription-polymerase chain reaction. Venezuelan equine encephalitis virus, dengue virus, West Nile virus, St. Louis encephalitis virus, yellow fever virus, and Culex flavivirus were detected and identified by sequencing. The detection of arboviral pathogens in this zone represents possible circulation and indicates a human health risk, demonstrating the importance of virological surveillance activities. PMID:27706377
Escobedo, A A; Cañete, R; Núñez, F A
2008-09-01
A cross-sectional study was carried out in 200 children aged 5-15 years, to examine the presence of intestinal parasitic infections (IPIs) and to assess the risk factors and clinical features associated with them in children in San Juan y Martinez (SIM), Cuba. Three fresh faecal samples were collected from each child and were examined by direct wet mount, brine flotation, formalin-ether and Kato-Katz techniques. Data relating to demography, source of drinking water, personal hygiene habits and clinical features were also collected Living in the rural area was significantly associated with the highest infection rates (p < 0.01). According to clinical features and laboratory examinations, children with abdominal pain were about four times more likely to have IPIs (OR 4.05, CI, 1.11, 13.18) especially soil-transmitted helminths (STH). We suggest that IPIs, especially STH, in SJM should be strongly suspected in children with abdominal pain from rural areas. Targeted and frequent interventions to control these infections are needed in this municipality.
Marcet, PL; Mora, MS; Cutrera, AP; Jones, L; Gürtler, RE; Kitron, U; Dotson, EM
2008-01-01
To gain an understanding of the genetic structure and dispersal dynamics of T. infestans populations, we analyzed the multilocus genotype of 10 microsatellite loci for 352 T. infestans collected in 21 houses of 11 rural communities in October 2002. Genetic structure was analyzed at the community and house compound levels. Analysis revealed that vector control actions affected the genetic structure of T. infestans populations. Bug populations from communities under sustained vector control (core area) were highly structured and genetic differentiation between neighboring house compounds was significant. In contrast, bug populations from communities with sporadic vector control actions were more homogeneous and lacked defined genetic clusters. Genetic differentiation between population pairs did not fit a model of isolation by distance at the microgeographical level. Evidence consistent with flight or walking bug dispersal was detected within and among communities, dispersal was more female-biased in the core area and results suggested that houses received immigrants from more than one source. Putative sources and mechanisms of re-infestation are described. These data may be use to design improved vector control strategies PMID:18773972
de la Campa, A M Sánchez; Pio, C; de la Rosa, J D; Querol, X; Alastuey, A; González-Castanedo, Y
2009-08-01
In the South of Spain, major industrial estates (e.g. Huelva) exist alongside ecologically interesting zones (e.g. Doñana National Park). Between June 2005 and June 2006, PM10 and PM2.5 were measured, for total mass, organic carbon (OC) and elemental carbon (EC) chemical composition, at a station in an ecologically interesting area located near Doñana National Park and an urban background area with industrial influence. The mean OC concentration is higher in the urban background (3.5 microg m(-3)) than in the rural monitoring station (2.8 microg m(-3)) as a consequence of local emissions (e.g. traffic). A total of 82% of TC is OC in the rural station, while the urban background station reveals 70% and 73% of TC in the PM10 and PM2.5 mass, respectively. The study of air-mass origin and characterization of carbonaceous species in the course of simultaneous sampling in rural and urban background monitoring stations differentiated three long-range air-mass transports: a North-African dust outbreak, Atlantic Advection and Continental (N-NW) episodes, the origins of the first and last of which are more heavily influenced by the anthropogenic emissions from industrial estates located around the city of Huelva (Punta del Sebo and Nuevo Puerto). Higher values were measured for OC and EC in the study area during the North-African dust outbreak, similar to those obtained during the Continental episode (N-NW), which was clearly influenced by industrial emissions, followed by the Atlantic Advection episodes. The comparison of carbon species with air-mass origin can help to discriminate the origin and source of particulate matter, as well as to determine the urban impact on rural areas.
Beek, J; Nauwynck, H; Appeltant, R; Maes, D; Van Soom, A
2015-11-01
Serine proteases are involved in mammalian fertilization. Inhibitors of serine proteases can be applied to investigate at which point these enzymes exert their action. We selected two serine protease inhibitors, 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF, 100 μM) and soybean trypsin inhibitor (STI, 5 μM) from Glycine max, via previous dose-response IVF experiments and sperm toxicity tests. In the present study, we evaluated how these inhibitors affect porcine fertilization in vitro as calculated on total fertilization rate, polyspermy rate, and the sperm number per fertilized oocyte of cumulus-intact, cumulus-free, and zona-free oocytes. In the control group (no inhibitor), these parameters were 86%, 49%, and 2.2 for cumulus-intact oocytes and 77%, 43%, and 2.2 for cumulus-free oocytes (6-hour gamete incubation period, 1.25 × 10(5) spermatozoa/mL). 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride and STI significantly reduced total fertilization and polyspermy rate in cumulus-intact and cumulus-free oocytes (P < 0.05). Total fertilization rates were respectively 65% and 53% (AEBSF) and 36% and 17% (STI). Inhibition rates were higher in cumulus-free oocytes than in cumulus-intact oocytes, indicating that inhibitors exerted their action after sperm passage through the cumulus. 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride but not STI reduced sperm binding to the ZP. The acrosome reaction was significantly inhibited by both inhibitors. Only 40.4% (AEBSF) and 11.4% (STI) of spermatozoa completed a calcium-induced acrosome reaction compared to 86.7% of spermatozoa in the control group. There was no effect on sperm binding or fertilization parameters in zona-free oocytes. In conclusion, sperm-zona binding and acrosome reaction were inhibited by serine protease inhibitors during porcine IVF. Copyright © 2015 Elsevier Inc. All rights reserved.
Quantitative assessment of CYP11B1 and CYP11B2 expression in aldosterone-producing adenomas.
Fallo, F; Pezzi, V; Barzon, L; Mulatero, P; Veglio, F; Sonino, N; Mathis, J M
2002-12-01
The presence and pathophysiological role of CYP11B1 (11beta-hydroxylase) gene in the zona glomerulosa of human adrenal cortex is still controversial. In order to specifically quantify CYP11B1, CYP11B2 (aldosterone synthase) and CYP17(17alpha-hydroxylase) mRNA levels, we developed a real-time RT-PCR assay and examined the expression in a series of adrenal tIssues, including six normal adrenals from patients adrenalectomized for renal cancer and twelve aldosterone-producing adenomas (APA) from patients with primary aldosteronism. CYP11B1 mRNA levels were clearly detected in normal adrenals, which comprised both zona glomerulosa and fasciculata/reticularis cells, but were also measured at a lower range (P<0.05) in APA. The levels of CYP11B2 mRNA were lower (P<0.005) in normal adrenals than in APA. CYP17 mRNAlevels were similar in normal adrenals and in APA. In patients with APA, CYP11B2 and CYP11B1 mRNA levels were not correlated either with basal aldosterone or with the change from basal aldosterone in response to posture or to dexamethasone. No correlation between CYP11B1 mRNA or CYP11B2 mRNA and the percentage of zona fasciculata-like cells was observed in APA. Real-time RT-PCR can be reliably used to quantify CYP11B1 and CYP11B2 mRNA levels in adrenal tIssues. Expression of CYP11B1 in hyperfunctioning zona glomerulosa suggests an additional formation of corticosterone via 11beta-hydroxylase, providing further substrate for aldosterone biosynthesis. CYP11B1 and CYP11B2 mRNA levels in APA are not related to the in vivo secretory activity of glomerulosa cells, where post-transcriptional factors might ultimately regulate aldosterone production.
Wang, Weiye; Wang, Lishan; Endoh, Akira; Hummelke, Geoffrey; Hawks, Christina L; Hornsby, Peter J
2005-01-01
In order to establish whether there are differences in DNA-binding proteins between zona fasciculata (ZF) and zona reticularis (ZR) cells of the human adrenal cortex, we prepared nuclear extracts from separated ZF and ZR cells. The formation of DNA-protein complexes was studied using an element in the first intron of the type I and type II 3beta-hydroxysteroid dehydrogenase genes (HSD3B1 and HSD3B2). Using the element in the HSD3B2 gene as a probe, a complex (C1) was formed with extracts from ZF cells but was formed only at a low level with ZR cell extracts. Another pair of complexes (C2/C3) was formed with both ZF and ZR cell extracts. The ZF-specific protein forming C1 was enriched by column chromatography on DEAE-Sepharose and carboxymethyl-Sepharose. Oligonucleotide competition analysis on the enriched fraction gave results consistent with those obtained on the unfractionated material. A further enrichment was brought about by passing the protein over an oligonucleotide affinity column based on the HSD3B2 element. The protein bound to the column was identified as alpha-enolase by mass spectrometry. Although alpha-enolase is a glycolytic enzyme, it binds to specific DNA sequences and has been found to be present in nuclei of various cell types. We performed immunohistochemistry on sections of adult human adrenal cortex and found alpha-enolase to be located in nuclei of ZF cells but to be predominantly cytoplasmic in ZR cells. Transfection of an alpha-enolase expression vector into NCI-H295R human adrenocortical cells increased HSD3B2 promoter activity, suggesting a possible functional role for this protein in regulation of HSD3B2 expression.
Common mental disorders and associated factors: a study of women from a rural area.
Parreira, Bibiane Dias Miranda; Goulart, Bethania Ferreira; Haas, Vanderlei José; Silva, Sueli Riul da; Monteiro, Juliana Cristina Dos Santos; Gomes-Sponholz, Flávia Azevedo; Parreira, Bibiane Dias Miranda; Goulart, Bethania Ferreira; Haas, Vanderlei José; Silva, Sueli Riul da; Monteiro, Juliana Cristina Dos Santos; Gomes-Sponholz, Flávia Azevedo
2017-05-25
Identifying the prevalence of Common Mental Disorders and analyzing the influence of sociodemographic, economic, behavioral and reproductive health variables on Common Mental Disorders in women of childbearing age living in the rural area of Uberaba-MG, Brazil. An observational and cross-sectional study. Socio-demographic, economic, behavioral and reproductive health instruments were used, along with the Self-Reporting Questionnaire (SRQ-20) to identify common mental disorders. Multiple logistic regression was used for multivariate data analysis. 280 women participated in the study. The prevalence of Common Mental Disorders was 35.7%. In the logistic regression analysis, the variables of living with a partner and education level were associated with Common Mental Disorders, even after adjusting for the other variables. Our findings evidenced an association of social and behavioral factors with Common Mental Disorders among rural women. Identification and individualized care in primary health care are essential for the quality of life of these women. Identificar a prevalência do transtorno mental comum e analisar a influência de variáveis sociodemográficas, econômicas, comportamentais e de saúde reprodutiva sobre o transtorno mental comum em mulheres em idade fértil, residentes na zona rural do município de Uberaba-MG, Brasil. Estudo observacional e transversal. Foram utilizados instrumentos de caracterização sociodemográfica, econômica, comportamental e de saúde reprodutiva, e o Self-Reporting Questionnaire (SRQ-20) para identificar os transtornos mentais comuns. Na análise multivariada dos dados, foi utilizada a regressão logística múltipla. Participaram do estudo 280 mulheres. A prevalência do transtorno mental comum foi de 35,7%. Na análise de regressão logística, as variáveis convivência com o companheiro e escolaridade, associaram-se ao transtorno mental comum, mesmo após o ajuste para as demais variáveis. Os achados evidenciaram a associação de fatores sociais e comportamentais com o transtorno mental comum, entre mulheres rurais. A identificação e a assistência individualizada na atenção primária de saúde são essenciais para a qualidade de vida destas mulheres. Identificar la prevalencia de trastornos mentales comunes y analizar la influencia de las variables socio-demográficas, económicas, de comportamiento y de salud reproductiva en el trastorno mental común en las mujeres en edad fértil, que viven en el municipio rural de Uberaba, Minas Gerais, Brasil. Estudio observacional y transversal. Se usaron instrumentos sociodemográficos, económicos, de comportamiento y salud reproductiva, y el Self-Reporting Questionnaire (SRQ-20) para identificar los trastornos mentales comunes. En el análisis multifactorial de los datos, se utilizó la regresión logística múltiple. El estudio incluyó a 280 mujeres. La prevalencia de los trastornos mentales comunes fue de 35,7%. En el análisis de regresión logística, las variables convivencia con su pareja y la escolarización se asociaron con trastorno mental común, incluso después de ajustar por otras variables. Los resultados muestran la relación entre los factores sociales y de comportamiento con el trastorno mental común entre las mujeres rurales. La identificación y la atención individual en la atención primaria de salud son esenciales para la calidad de vida de las mujeres.
NASA Astrophysics Data System (ADS)
Oki, Delwyn S.; Souza, William R.; Bolke, Edward L.; Bauer, Glenn R.
The coastal aquifer system of southern Oahu, Hawaii, USA, consists of highly permeable volcanic aquifers overlain by weathered volcanic rocks and interbedded marine and terrestrial sediments of both high and low permeability. The weathered volcanic rocks and sediments are collectively known as caprock, because they impede the free discharge of groundwater from the underlying volcanic aquifers. A cross-sectional groundwater flow and transport model was used to evaluate the hydrogeologic controls on the regional flow system in southwestern Oahu. Controls considered were: (a) overall caprock hydraulic conductivity; and (b) stratigraphic variations of hydraulic conductivity in the caprock. Within the caprock, variations in hydraulic conductivity, caused by stratigraphy or discontinuities of the stratigraphic units, are a major control on the direction of groundwater flow and the distribution of water levels and salinity. Results of cross-sectional modeling confirm the general groundwater flow pattern that would be expected in a layered coastal system. Groundwater flow is: (a) predominantly upward in the low-permeability sedimentary units; and (b) predominantly horizontal in the high-permeability sedimentary units. Résumé Le système aquifère littoral du sud d'Oahu (Hawaii, États-Unis) est constitué par des aquifères de terrains volcaniques très perméables, recouverts par des roches volcaniques altérées, et interstratifiés avec des sédiments marins et continentaux de perméabilité aussi bien forte que faible. Les roches volcaniques altérées et les sédiments sont globalement considérés comme une couverture, parce qu'ils s'opposent à l'écoulement de l'eau souterraine provenant des aquifères volcaniques sous-jacents. Les contrôles hydrogéologiques sur le système aquifère régional du sud-ouest d'Oahu ont étéévaluées au moyen d'un modèle d'écoulement et de transport sur une section transversale. Ces contrôles prennent en compte la conductivité hydraulique de la couverture dans son ensemble et les variations de la conductivité hydraulique liées à la stratigraphie de la couverture. A l'intérieur de la couverture, les variations de la conductivité hydraulique, dues à la stratigraphie ou à des discontinuités entre les unités stratigraphiques, sont le contrôle principal de la direction d'écoulement et de la répartition des niveaux et de la salinité de l'eau. La modélisation sur une section transversale a donné des résultats qui confirment l'organisation générale des directions d'écoulement, telle qu'elle pouvait être envisagée dans un aquifère littoral multicouche. L'écoulement souterrain est essentiellement vertical vers le haut dans les unités sédimentaires à faible perméabilité, et essentiellement horizontal dans les unités sédimentaires à forte perméabilité. Resumen El sistema acuífero costero de la zona sur de Oahu, en Hawaii, está formado por acuíferos volcánicos de alta permeabilidad, subyacentes a rocas volcánicas alteradas, con inclusiones de sedimentos marinos y terrestres, tanto de alta como de baja permeabilidad. Al conjunto de rocas volcánicas alteradas y sedimentos se le conoce por "tapón de roca", ya que impide la descarga libre de las aguas subterráneas del acuífero volcánico subyacente. Se usó un modelo de flujo de agua subterránea y transporte de solutos en sección vertical para evaluar los aspectos hidrogeológicos que controlan el flujo regional en la zona sudoeste de Oahu. Se consideraron: (a) la conductividad hidráulica global del tapón y (b) las variaciones estratigráficas de la conductividad hidráulica. En el tapón de roca, las variaciones de la conductividad hidráulica, causadas por la estratigrafía o por discontinuidades en las unidades estratigráficas, son las que controlan la dirección del flujo subterráneo y la distribución de niveles piezométricos y salinidad. Los resultados del modelo en sección transversal confirman la distribución del flujo subterráneo que cabría esperar en un sistema costero estratificado. El flujo de aguas subterráneas es: (a) predominantemente vertical hacia arriba en las unidades sedimentarias de baja permeabilidad; y (b) predominantemente horizontal en las unidades sedimentarias de alta permeabilidad.
Edenfeld, J; Schöpper, B; Sturm, R; Diedrich, K; Al-Hasani, S
2002-04-01
Laser systems are very promising new technical tools in assisted reproduction. It was investigated if laser radiation can replace the mechanical cutting procedure via micromanipulator in the hemizona assay (HZA), a commonly used bioassay to determine the sperm-zona pellucida binding capacity. An oocyte was bisected precisely into two identical hemizonae with approximately 20 laser pulses (pulse length 30 msec) using a 1.48-microm diode laser. Compared with the conventional method using microscalpels for zona bisection, laser treated hemizonae showed equivalent sperm-binding and within the two groups there was no detectable difference between matching hemizonae in their capacity for tight sperm-binding. To evaluate whether laser radiation affects the outcome of the HZA when effects of certain substances are investigated, the spermatozoa were preincubated with human follicular fluid (hFF), which inhibits the binding of spermatozoa to zona pellucida in vitro. Supplementation with follicular fluid exerted an inhibitory effect in both groups. The hemizona index (HZI) showed no statistical differences between the two methods. Therefore, the 1.48-microm diode laser is a suitable new instrument for generating equally sized hemizonae. There is no use for holding pipettes and microscalpels, on the contrary, for performing the HZA the laser is a precise, very quick and easy to use new working tool.
Cysteine-rich secretory proteins (CRISP) and their role in mammalian fertilization.
Cohen, Débora J; Maldera, Julieta A; Weigel Muñoz, Mariana; Ernesto, Juan I; Vasen, Gustavo; Cuasnicu, Patricia S
2011-01-01
Epididymal protein CRISPI is a member of the CRISP (Cysteine-RIch Secretory proteins) family and is involved in sperm-egg fusion through its interaction with complementary sites on the egg surface. Results from our laboratory have shown that this binding ability resides in a 12-amino-acid region corresponding to a highly conserved motif of the CRISP family, named Signature 2 (S2). In addition to this, our results revealed that CRISP1 could also be involved in the previous step of sperm binding to the zona pellucida, identifying a novel role for this protein in fertilization. As another approach to elucidate the participation of CRISP1 in fertilization, a mouse line containing a targeted disruption of CRISP1 was generated. Although CRISP1-deficient mice exhibited normal fertility, CRISP1-defficient sperm presented a decreased level of protein tyrosine phosphorylation during capacitation, and an impaired ability to fertilize both zona-intact and zona-free eggs in vitro, confirming the proposed roles for the protein in fertilization. Evidence obtained in our laboratory indicated that testicular CRISP2 would also be involved in sperm-egg fusion. Competition assays between CRISP1 and CRISP2, as well as the comparison of their corresponding S2 regions, suggest that both proteins bind to common complementary sites in the egg. Together, these results suggest a functional cooperation between CRISP1 and CRISP2 to ensure the success of fertilization.
Mori, Chiemi; Yabuuchi, Akiko; Ezoe, Kenji; Murata, Nana; Takayama, Yuko; Okimura, Tadashi; Uchiyama, Kazuo; Takakura, Kei; Abe, Hiroyuki; Wada, Keiko; Okuno, Takashi; Kobayashi, Tamotsu; Kato, Keiichi
2015-06-01
Hydroxypropyl cellulose (HPC) was investigated as a replacement for serum substitute supplement (SSS) for use in cryoprotectant solutions for embryo vitrification. Mouse blastocysts from inbred (n = 1056), hybrid (n = 128) strains, and 121 vitrified blastocysts donated by infertile patients (n = 102) were used. Mouse and human blastocysts, with or without zona pellucida, were vitrified and warmed in either 1% or 5% HPC or in 5% or 20% SSS-supplemented media using the Cryotop (Kitazato BioPharma Co. Ltd, Fuji, Japan) method, and the survival and oxygen consumption rates were assessed. Viscosity of each vitrification solution was compared. Survival rates of mouse hybrid blastocysts and human zona pellucida-intact blastocysts were comparable among the groups. Mouse and human zona pellucida-free blastocysts, which normally exhibit poor cryoresistance, showed significantly higher survival rates in 5% HPC than 5% SSS (P < 0.05). The 5% HPC-supplemented vitrification solution showed a significantly higher viscosity (P < 0.05). The blastocysts were easily detached from the Cryotop strip during warming when HPC-supplemented vitrification solution was used. The oxygen consumption rates were similar between non-vitrified and 5% HPC groups. The results suggest possible use of HPC for supplementation of cryoprotectant solutions and provide useful information to improve vitrification protocols. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Kitchener, Anne L; Harman, Amanda; Kay, David J; McCartney, Carmen A; Mate, Karen E; Rodger, John C
2009-01-01
This study examined the potential of a recombinant marsupial zona pellucida 3 protein as a contraceptive vaccine for the Eastern Grey kangaroo, a marsupial that is locally overabundant in several regions of eastern Australia. First, a pilot study using porcine zona pellucidae (PZP) demonstrated that ZP proteins, primarily the ZP3 component of PZP, are highly immunogenic in the grey kangaroo and produce a long-lasting humoral response to a single immunisation, as found in other marsupials. Immunisation with 300 microg of a non-glycosylated recombinant brushtail possum ZP3 (recBP-ZP3) protein in complete Freund's adjuvant produced a similar, significant and sustained antibody response, and none of the immunised kangaroos (n=7) produced offspring during the following breeding season compared with four out of the six control animals. An epitope analysis of the B-cell response to recBP-ZP3 using a brushtail possum ZP3 identified numerous B-cell epitope regions clustered around the N- and C-terminal regions of the protein. Two regions of interest for further fertility vaccine development based on their immunogenicity and fertility trials and functional studies in other species were found to be immunogenic. These results suggest that immunocontraception based on targeting the ZP3 protein within the zona pellucida may be an effective strategy for fertility reduction in Eastern Grey kangaroos.
Provecho, Yael M; Gaspe, M Sol; del Pilar Fernández, M; Enriquez, Gustavo F; Weinberg, Diego; Gürtler, Ricardo E
2014-01-01
Peri-urban infestations with triatomine bugs, their sources and their dynamics have rarely been investigated. Here, we corroborated the reported occurrence of Triatoma infestans in a peri-urban area and in neighbouring rural houses in Pampa del Indio, in the Argentine Chaco, and identified its putative sources using spatial analysis and demographic questionnaires. Peri-urban householders reported that 10% of their premises had triatomines, whereas T. infestans was collected by timed manual searches or community-based surveillance in only nine (3%) houses. Trypanosoma cruzi-infected T. infestans and Triatoma sordida were collected indoors only in peri-urban houses and were infected with TcV and TcI, respectively. The triatomines fed on chickens, cats and humans. Peri-urban infestations were most frequent in a squatter settlement and particularly within the recently built mud houses of rural immigrants, with large-sized households, more dogs and cats and more crowding. Several of the observed infestations were most likely associated with passive bug transport from other sources and with active bug dispersal from neighbouring foci. Thus, the households in the squatter settlement were at a greater risk of bug invasion and colonisation. In sum, the incipient process of domestic colonisation and transmission, along with persistent rural-to-urban migratory flows and unplanned urbanisation, indicate the need for active vector surveillance and control actions at the peri-urban interface of the Gran Chaco. PMID:25410997
Exploration of an alluvial aquifer in Oman by time-domain electromagnetic sounding
NASA Astrophysics Data System (ADS)
Young, M. E.; de Bruijn, R. G. M.; Al-Ismaily, A. Salim
One-third of the population of Oman depends upon groundwater extracted from the alluvium of the Batinah Plain, on the coast of the Gulf of Oman. Deep geophysical exploration techniques were used to determine the depth and nature of the alluvium and the boundaries of the aquifer. The base and structural controls of the alluvial basin at its contact with Tertiary marine sediments and Cretaceous ophiolite were mapped with seismic reflection data, recorded originally for oil exploration. The base of the alluvium dips northward from the foothills of the Northern Oman Mountains, reaching a maximum depth of 2000m at the coast. The varying facies of the alluvium are grossly characterised by different, overlapping ranges of electrical resistivity, depending largely on the clay content and degree of cementation. Resistivities near the coast are reduced by saline intrusion. These variations of resistivity were mapped with time-domain electromagnetic sounding along 400km of profile, to distinguish among the three zones of the alluvial aquifer. The wedge of saline intrusion was also delineated, up to 10km from the coast. The thickness of the saturated gravel aquifer ranges from 20-160m in an area greater than 600km2. Résumé Un tiers de la population d'Oman est alimenté par de l'eau souterraine pompée dans les alluvions de la plaine de Batinah, sur la côte du golfe d'Oman. Des techniques d'exploration géophysique profonde ont été mises en oeuvre pour déterminer la profondeur et la nature des alluvions et les limites de l'aquifère. La base et les contrôles structuraux du bassin alluvial au contact des sédiments marins tertiaires et des ophiolites crétacées ont été cartographiés à partir des données de sismique réflexion obtenues à l'origine pour la recherche pétrolière. La base des alluvions plonge vers le nord à partir du piémont du massif septentrional d'Oman, pour atteindre une profondeur maximale de 2000m sur la côte. Les divers faciès alluviaux sont grossièrement caractérisés par des différentes gammes de résistivitéélectrique se recouvrant, dépendant surtout de la teneur en argiles et du degré de cimentation. Les résistivités près de la côte diminuent du fait de l'intrusion marine. Ces variations de résistivité ont été cartographiées à partir de 400km de profils électromagnétiques, dans le domaine temporel ; trois zones ont été distinguées dans l'aquifère alluvial. Le biseau salé a aussi été délimité, jusqu'à 10km de la côte. L'épaisseur de la partie saturée des graviers va de 20-160m sur une étendue supérieure à 600km2. Resumen Un tercio de la población de Omán depende de las aguas subterráneas extraídas del aluvial de la Llanura de Batinah, en la costa del Golfo de Omán. Para determinar la profundidad y naturaleza del aluvial, así como los límites del acuífero, se han usado técnicas de exploración geofísica profunda. El basamento y los límites estructurales del aluvial en su contacto con los sedimentos marinos del Terciario y la ofiolita cretácica se obtuvieron mediante sísmica de reflexión, registrada previamente en campañas de exploración petrolífera. La base del aluvial buza hacia el norte desde el pie de las Montañas del Norte de Omán, alcanzando una profundidad máxima de 2000m en la costa. Las distintas facies del aluvial están caracterizadas por rangos distintos, pero superpuestos, de resistividad eléctrica, dependiendo del contenido en arcillas y del grado de cementación. Las resistividades cerca de la costa se reducen por la intrusión salina. Estas variaciones de resistividad se obtuvieron con registros electromagnéticos a lo largo de un perfil de 400km, con el objetivo de distinguir las tres zonas del acuífero aluvial. También se pudo obtener la geometría de la cuña de intrusión, que llega hasta 10km de la costa. El espesor de las gravas saturadas que forman el acuífero oscila entre los 20-160m en un área superior a 600km2.
Pipal, A S; Tiwari, S; Satsangi, P G; Taneja, Ajay; Bisht, D S; Srivastava, A K; Srivastava, M K
2014-01-01
Agra, one of the oldest cities "World Heritage site", and Delhi, the capital city of India are both located in the border of Indo-Gangetic Plains (IGP) and heavily loaded with atmospheric aerosols due to tourist place, anthropogenic activities, and its topography, respectively. Therefore, there is need for monitoring of atmospheric aerosols to perceive the scenario and effects of particles over northern part of India. The present study was carried out at Agra (AGR) as well as Delhi (DEL) during winter period from November 2011 to February 2012 of fine particulate (PM₂.₅: d < 2.5 μm) as well as associated carbonaceous aerosols. PM₂.₅ was collected at both places using medium volume air sampler (offline measurement) and analyzed for organic carbon (OC) and elemental carbon (EC). Also, simultaneously, black carbon (BC) was measured (online) at DEL. The average mass concentration of PM₂.₅ was 165.42 ± 119.46 μg m(-3) at AGR while at DEL it was 211.67 ± 41.94 μg m(-3) which is ~27% higher at DEL than AGR whereas the BC mass concentration was 10.60 μg m(-3). The PM₂.₅ was substantially higher than the annual standard stipulated by central pollution control board and United States Environmental Protection Agency standards. The average concentrations of OC and EC were 69.96 ± 34.42 and 9.53 ± 7.27 μm m(-3), respectively. Total carbon (TC) was 79.01 ± 38.98 μg m(-3) at AGR, while it was 50.11 ± 11.93 (OC), 10.67 ± 3.56 μg m(-3) (EC), and 60.78 ± 14.56 μg m(-3) (TC) at DEL. The OC/EC ratio was 13.75 at (AGR) and 5.45 at (DEL). The higher OC/EC ratio at Agra indicates that the formation of secondary organic aerosol which emitted from variable primary sources. Significant correlation between PM₂.₅ and its carbonaceous species were observed indicating similarity in sources at both sites. The average concentrations of secondary organic carbon (SOC) and primary organic carbon (POC) at AGR were 48.16 and 26.52 μg m(-3) while at DEL it was 38.78 and 27.55 μg m(-3), respectively. In the case of POC, similar concentrations were observed at both places but in the case of SOC higher over AGR by 24 in comparison to DEL, it is due to the high concentration of OC over AGR. Secondary organic aerosol (SOA) was 42% higher at AGR than DEL which confirms the formation of secondary aerosol at AGR due to rural environment with higher concentrations of coarse mode particles. The SOA contribution in PM₂.₅ was also estimated and was ~32 and 12% at AGR and DEL respectively. Being high loading of fine particles along with carbonaceous aerosol, it is suggested to take necessary and immediate action in mitigation of the emission of carbonaceous aerosol in the northern part of India.
2015-01-01
Background Selection of the best oocyte for subsequent steps of fertilization and embryo transfer was shown to be the crucial step in human infertility treatment procedure. Oocyte selection using morphological criteria mainly Zona pellucida (ZP) has been the gold standard method in assisted reproductive technologies (ART) clinics, but this selection approach has limitations in terms of accuracy, objectivity and constancy. Recent studies using OMICs-based approaches have allowed the identification of key molecular markers that quantitatively and non-invasively predict the oocyte quality for higher pregnancy rates and efficient infertility treatment. These biomarkers are a valuable reinforcement of the morphological selection criteria widely used in in vitro fertilization (IVF) clinics. In this context, this study was designed to investigate the relationship between transcriptomic predictors of oocyte quality found by our group and the conventional morphological parameters of oocyte quality mainly the ZP birefringence. Results Microarray data revealed that 48 and 27 differentially expressed candidate genes in cumulus cells (CCs) were respectively overexpressed and underexpressed in the ZGP (Zona Good Pregnant) versus ZBNP (Zona Bad Non Pregnant) groups. More than 70% of previously reported transcriptomic biomarkers of oocyte developmental competence were confirmed in this study. The analysis of possible association between ZP birefringence versus molecular markers approach showed an absence of correlation between them using the current set of markers. Conclusions This study suggested a new integrative approach that matches morphological and molecular approaches used to select developmentally competent oocytes able to lead to successful pregnancy and the delivery of healthy baby. For each ZP birefringence score, oocytes displayed a particular CCs' gene expression pattern. However, no correlations were found between the 7 gene biomarkers of oocyte developmental potential and the ZP birefringence score. Further studies using larger lists of candidate markers are required to identify suitable genes that are highly correlated with the morphological criteria, and therefore able to reinforce the accuracy of oocyte selection and the effectiveness of infertility treatment. PMID:25923296
Mesbah, F; Kafi, M; Nili, H
2016-12-01
The morphological and morphometric characteristics of the ovary are fundamental properties for in vitro oocyte maturation. Nuclear maturation, including first polar body (1PB) extrusion, cytoplasmic maturation and cumulus cell (CC) expansion are the criteria for in vitro maturation (IVM) of oocyte. This study was designed to determine the effect of morphological and morphometric features of the ovary on CC expansion and 1PB extrusion during IVM of oocyte in the adult female dromedary camel. The weight, volume and three dimensions of ovaries from slaughtered dromedary camels and oocytes inside zona diameter and zona pellucida thickness were measured. The follicles were classified in regard to the size and oocytes according to their ooplasm appearance and CC compactness. Aspirated cumulus oocyte complexes (COCs) were incubated for 48 hr (with a 6-hr interval) in Hams-F10, and CC expansion and 1PB extrusion were assessed. Significant differences were seen in the shape, weight, volume and three dimensions of the ovaries between ≤4-year-old and >4-year-old dromedary camel (p < .5). Approximately, 95.82% of follicles were 2-4 mm in diameter. The mean (±SD) of inside zona diameter of the oocyte and zona pellucida thickness was 132.22 ± 13.8 and 14.64 ± 2.24 μm, respectively, in >4-year-old dromedary camel. The CC expansion and 1PB extrusion were seen in 86% and 21.88% of COCs, respectively. Age and sexual conditions of dromedary camel influence the morphological and morphometric characteristics of the ovary. Most COCs retrieved from 2-6 mm follicles are cultivable. The most slaughterhouse-derived COCs retrieved from 2-6 mm follicles of non-pregnant dromedary camels are excellent and good and yielding a most favourable diameter to achieve the developmental competence for IVM in an optimal time of 24-30 hr; the optimal time for CC expansion is 24-30 hr in this species. However, the CC expansion is a prerequisite process, but not sufficient for IVM. © 2016 Blackwell Verlag GmbH.
De Silva, Matharage S I; Dayton, Adam W; Rhoten, Lance R; Mallett, John W; Reese, Jared C; Squires, Mathieu D; Dalley, Andrew P; Porter, James P; Judd, Allan M
2018-06-01
In bovine adrenal zona fasciculata (ZF) and NCI-H295R cells, interleukin-6 (IL-6) increases cortisol release, increases expression of steroidogenic acute regulatory protein (StAR), cholesterol side chain cleavage enzyme (P450scc), and steroidogenic factor 1 (SF-1) (increases steroidogenic proteins), and decreases the expression of adrenal hypoplasia congenita-like protein (DAX-1) (inhibits steroidogenic proteins). In contrast, IL-6 decreases bovine adrenal zona reticularis (ZR) androgen release, StAR, P450scc, and SF-1 expression, and increases DAX-1 expression. Adenosine monophosphate (AMP) activated kinase (AMPK) regulates steroidogenesis, but its role in IL-6 regulation of adrenal steroidogenesis is unknown. In the present study, an AMPK activator (AICAR) increased (P < 0.01) NCI-H295R StAR promoter activity, StAR and P450scc expression, and the phosphorylation of AMPK (PAMPK) and acetyl-CoA carboxylase (PACC) (indexes of AMPK activity). In ZR (decreased StAR, P450scc, SF-1, increased DAX-1) (P < 0.01) and ZF tissues (increased StAR, P450scc, SF-1, decreased DAX-1) (P < 0.01), AICAR modified StAR, P450scc, SF-1 and DAX-1 mRNAs/proteins similar to the effects of IL-6. The activity (increased PAMPK and PACC) (P < 0.01) of AMPK in the ZF and ZR was increased by AICAR and IL-6. In support of an AMPK role in IL-6 ZF and ZR effects, the AMPK inhibitor compound C blocked (P < 0.01) the effects of IL-6 on the expression of StAR, P450scc, SF-1, and DAX-1. Therefore, IL-6 modification of the expression of StAR and P450scc in the ZF and ZR may involve activation of AMPK and these changes may be related to changes in the expression of SF-1 and DAX-1. Copyright © 2018 Elsevier Inc. All rights reserved.
STUDIES ON THE ORIGIN OF CIRCULATING 18-HYDROXYCORTISOL AND 18-OXOCORTISOL IN NORMAL HUMAN SUBJECTS.
Freel, E Marie; Shakerdi, Loai A; Friel, Elaine C; Wallace, A Michael; Davies, Eleanor; Fraser, Robert; Connell, John MC
2005-01-01
18-hydroxycortisol (18-OHF) and 18-oxocortisol (18oxo-F) are derivatives of cortisol found in Primary Aldosteronism but whose origin and regulation in normal subjects is uncertain. 18-OHF can be synthesised by zona fasciculata 11-β hydroxylase; 18-oxoF can only be produced by zona glomerulosa aldosterone synthase (AS). Stably transfected cell lines expressing either CYP11B1 (11β-hydroxylase) or CYP11B2 (AS) were incubated with cortisol and other substrates over a range of concentrations. Both enzymes could synthesise 18-OHF from cortisol but only AS could synthesise 18-oxoF. AS was more efficient than 11β-hydroxylase at 18-hydroxylation. The apparent Km of AS for cortisol was estimated to be 2.6μM. In 5 patients with adrenal insufficiency maintained on hydrocortisone, urinary free cortisol and cortisone levels were high; 18-oxoF was detectable in all patients and 18-hydroxycortisol in 3. It is likely that the 18-oxygenated steroids were synthesised from circulating cortisol, either in the zona glomerulosa or at extra-adrenal sites. In 8 male volunteers, dexamethasone treatment decreased urinary excretion rates of free cortisol, cortisone, 18-OHF and 18-oxoFl, confirming dependence of 18-oxygenated steroid levels on cortisol availability. In both groups, hydrocortisone administration resulted in detectable levels of 18-OHF and raised levels of 18-oxoF. There was close correlation between 18-oxoF and cortisol excretion during hydrocortisone administration in normal subjects (r=0.86, p<0.001). These data show, for the first time, that 18-OHF and 18oxoF can be synthesised from circulating cortisol. The close correlation between 18-oxoF and cortisol suggests that 18-oxoF is normally produced by the action of aldosterone synthase utilising circulating cortisol as a substrate. Although 18OHF can be synthesized using circulating cortisol as substrate, our data suggest this is normally produced in the zona fasciculata by 11β-hydroxylase from locally available cortisol. PMID:15356073
ENRIQUEZ, G.F.; CARDINAL, M.V.; OROZCO, M.M.; LANATI, L.; SCHIJMAN, A.G.; GÜRTLER, R.E.
2013-01-01
SUMMARY The discrete typing units (DTUs) of Trypanosoma cruzi that infect domestic dogs and cats have rarely been studied. With this purpose we conducted a cross-sectional xenodiagnostic survey of dog and cat populations residing in two infested rural villages in Pampa del Indio, in the humid Argentine Chaco. Parasites were isolated by culture from 44 dogs and 12 cats with a positive xenodiagnosis. DTUs were identified from parasite culture samples using a strategy based on multiple polymerase-chain reactions. TcVI was identified in 37 of 44 dogs and in 10 of 12 cats, whereas TcV was identified in five dogs and in two cats –a new finding for cats. No mixed infections were detected. The occurrence of two dogs infected with TcIII –classically found in armadillos– suggests a probable link with the local sylvatic transmission cycle involving Dasypus novemcinctus armadillos and a potential risk of human infection with TcIII. Our study reinforces the importance of dogs and cats as domestic reservoir hosts and sources of various DTUs infecting humans, and suggests a link between dogs and the sylvatic transmission cycle of TcIII. PMID:23058180
Artola-Bordás, F; Arnedo-Pena, A; Romeu-García, M A; Bellido-Blasco, J B
2008-01-01
To describe a dermatitis outbreak caused by exposure to pine processionary caterpillar (Thaumetopoea pityocampa ) that took place on March 15th, 2006, in schoolchildren during their stay at a rural farm holiday centre in Villahermosa del Río (Castellón). A cross sectional epidemiological study was carried out on seventy schoolchildren, average age 10 years, and 3 teachers from Castellón. A specific questionnaire was used to be filled in by the schoolchildren. Six cases of dermatitis (attack rate 8.6%: 6/70) took place after children had swum in the heated farm pool and dried themselves with towels that had been left outside the heated pool enclosure, where they had come into contact with Thaumetopoea pityocampa. The cases needed medical attention, with prescription of antihistamine drugs, corticosteroids, and cold showers. The risk of dermatitis from contact with Thaumetopoea pityocampa was very high (Odds Ratio=157.2 Confidence Interval 95% 18.4-inf). Thaumetopoea pityocampa were collected near the swimming pool and Thaumetopoea pityocampa nests were observed on nearby pines. The presence of Thaumetopoea pityocampa near rural centres can cause outbreaks. Health education for schoolchildren and the removal of Thaumetopoea pityocampa nests near these centres are required.
NASA Astrophysics Data System (ADS)
Escobar, C. M.; Lopez, A.; Aristizabal, H. F.; Molina, J. M.
2010-07-01
Experimental efforts with fog collection in Colombia began eight years ago, and in recent papers we have suggested the implementation of operational fog collection as an alternative to meet water requirements in rural areas of the Andes Mountain Range. Since then, an increasing number of individuals from academia and environmental organizations in the country have shown a remarkable interest on this appropriate technology, and some started its exploration in a larger scale. In this work we describe the implementation process of the first operational fog collection project in Colombia and discuss its role in rural water supply, in environmental education issues and in the process of "social reintegration" of people who have been victims of forced displacement. Both the fog collection evaluation stage and construction and administration of the operational system involved the participation of the community of a rural village. The study zone, located in the Andes Mountains of the Valle del Cauca Department and with altitudes ranging from 2600 to 2800 meters a.s.l., has serious limitations in water availability. Eight standard fog collectors (SFC) were implemented and used during the period May/2008 - Feb/2009 in order to assess the water yield from fog. The best average monthly collection rate in the period of study was around 2.0 l.m-2.day-1. The constructed large fog collector (LFC), with a vertical collection surface of 25 m2, and the associated hydraulic system are currently managed and administered by the village inhabitants. The fog collection system benefits a rural school, and the water is mainly used in small-scale irrigation activities for horticultural crops and livestock development. The project has also brought positive impacts in the community organization, mainly comprising people who have been forced out of their rural homes by the country's nearly half-century old armed conflict. The system also allows agriculture- and environment-related issues to be incorporated in children's current education. We highly recommend exploring this technology in the search for solutions of water and food security for victims of forced displacement in Colombia. Additional efforts to increase the number of LFCs in the study zone are underway.
Caffeine delays oocyte aging and maintains the quality of aged oocytes safely in mouse.
Zhang, Xia; Liu, Xiaoyan; Chen, Li; Wu, Dan-Ya; Nie, Zheng-Wen; Gao, Ying-Ying; Miao, Yi-Liang
2017-03-28
Caffeine, as an oocyte aging inhibitor, was used in many different species to control or delay oocyte aging. However, the safety of caffeine and developmental competence of aged oocytes inhibited by caffeine has not been studied systematically. So we detected the spindle morphology, distribution of cortical granules, zona pellucida hardening and pronucleus formation to assess oocyte quality of caffeine treated oocytes. We found that aged oocytes treated by caffeine maintained weak susceptibility to activating stimuli and regained normal competent after aged further 6 hr. Caffeine maintained the spindle morphology, changed cortical granules distribution of aged oocytes and could not prevent zona pellucida hardening. Furthermore, caffeine increased pronucleus formation of aged oocytes and decreased fragmentation after fertilization. These results suggested that caffeine could maintain the quality of aged oocytes safely in mouse.
Louros, Nikolaos N; Chrysina, Evangelia D; Baltatzis, Georgios E; Patsouris, Efstratios S; Hamodrakas, Stavros J; Iconomidou, Vassiliki A
2016-03-01
Human zona pellucida (ZP) is composed of four glycoproteins, namely ZP1, ZP2, ZP3 and ZP4. ZP proteins form heterodimers, which are incorporated into filaments through a common bipartite polymerizing component, designated as the ZP domain. The latter is composed of two individually folded subdomains, named ZP-N and ZP-C. Here, we have synthesized six 'aggregation-prone' peptides, corresponding to a common interface of human ZP2, ZP3 and ZP4. Experimental results utilizing electron microscopy, X-ray diffraction, ATR FT-IR spectroscopy and polarizing microscopy indicate that these peptides self-assemble forming fibrils with distinct amyloid-like features. Finally, by performing detailed modeling and docking, we attempt to shed some light in the self-assembly mechanism of human ZP proteins. © 2016 Federation of European Biochemical Societies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurachi, H.; Wakimoto, H.; Sakumoto, T.
1984-02-01
The specific radioimmunoassay system was developed for the titration of the antibodies to porcine zona pellucida (ZP) in human sera by using /sup 125/I-labeled purified porcine ZP as antigen, which is known to have cross-reactivity with human ZP. The antibodies in human sera were detected in 3 of 11 (27%) women with unexplained infertility, in 16 of 48 (33%) amenorrheic patients, in 4 of 12 (33%) fertile women, and in 3 of 10 (30%) men. Moreover, antibody titers in infertile women were no higher than those in fertile women and in men. These results seem to suggest that the antibodiesmore » in human sera that cross-react with porcine ZP may not be an important factor in causing infertility in women.« less
Effect of acute heat stress on rat adrenal glands: a morphological and stereological study.
Koko, Vesna; Djordjeviae, Jelena; Cvijiae, Gordana; Davidoviae, Vukosava
2004-11-01
The morphological and stereological structure of rat adrenal gland was analysed by light microscopy after an acute (60 min) exposure to high ambient temperature (38 degrees C). A significant increase in plasma corticotrophin (ACTH) and serum corticosterone (CORT) concentrations was observed, confirming that acute heat exposure has a strong stressful effect. Under these conditions the adrenal gland mass and volume were decreased, probably as the consequence of adrenal cortex reduction, especially that of the zona fasciculata (ZF). Histological examination revealed that many ZF cells were deprived of lipid droplets. Fibrosis was observed in all parts of the adrenal gland, both cortex and medulla, of heat stressed animals. Mitotic figures were absent in cortical cells after heat exposure, but there were no differences in ZF and zona reticularis (ZR) small blood vessels compared to nonstressed controls.
Hou, S T; Ma, A; Jones, R; Hall, L
1996-10-01
The rat sperm surface antigen, 2B1, that has been proposed to play a key role in sperm adhesion to the zona pellucida, has been cloned and its entire cDNA sequenced. Northern blot analysis indicates that 2B1 is encoded by a 2.2-kb RNA transcript that is abundantly expressed in the testis. The deduced protein sequence contains 512 amino-acid residues with a strong candidate signal sequence and C-terminal transmembrane domain. Data base searches reveal a high degree of sequence similarity to guinea pig, rabbit, monkey, and human PH20 sperm surface antigens, and a lower degree of similarity to honey bee and whiteface hornet venom hyaluronidases. Rat 2B1 antigen also possesses hyaluronidase activity, suggesting that it is a bifunctional protein with putative roles in the dispersion of cumulus oophorus cells as well as zona adhesion. However, while it would appear that 2B1 is the rat homologue of the guinea pig PH20 antigen, they differ in a number of important biochemical respects (including their mode of attachment to the sperm membrane and distribution between soluble and membrane-bound fractions), as well as in their localization on the sperm membrane. Expression of regions of the 2B1 protein in recombinant bacterial cells has allowed a preliminary mapping of the 2B1 epitope, and has provided more definitive information on the endoproteolytic processing of 2B1 during epididymal transit.
Okumura, Hiroki
2017-01-01
An ovulated egg of vertebrates is surrounded by unique extracellular matrix, the egg coat or zona pellucida, playing important roles in fertilization and early development. The vertebrate egg coat is composed of two to six zona pellucida (ZP) glycoproteins that are characterized by the evolutionarily conserved ZP-domain module and classified into six subfamilies based on phylogenetic analyses. Interestingly, investigations of biochemical and functional features of the ZP glycoproteins show that the roles of each ZP-glycoprotein family member in the egg-coat formation and the egg-sperm interactions seemingly vary across vertebrates. This might be one reason why comprehensive understandings of the molecular basis of either architecture or physiological functions of egg coat still remain elusive despite more than 3 decades of intensive investigations. In this chapter, an overview of avian egg focusing on the oogenesis are provided in the first section, and unique features of avian egg coat, i.e., perivitelline layer, including the morphology, biogenesis pathway, and physiological functions are discussed mainly on chicken and quail in terms of the characteristics of ZP glycoproteins in the following sections. In addition, these features of avian egg coat are compared to mammalian zona pellucida, from the viewpoint that the structural and functional varieties of ZP glycoproteins might be associated with the evolutionary adaptation to their reproductive strategies. By comparing the egg coat of birds and mammals whose reproductive strategies are largely different, new insights into the molecular mechanisms of vertebrate egg-sperm interactions might be provided.
Characterization of angiotensin receptors on bovine adrenal fasciculata cells.
Vallotton, M B; Capponi, A M; Grillet, C; Knupfer, A L; Hepp, R; Khosla, M C; Bumpus, F M
1981-01-01
We have further characterized angiotensin receptors on bovine adrenal fasciculata cells whose presence was previously demonstrated by the intrinsic agonistic activity of angiotensin II (AII), dex-Asp1-AII, angiotensin I (AI), and des-ASp1-AI on steroidogenesis. The specific binding of AII and des-Asp1-AII labeled with 125I to dispersed bovine fasciculata cells was studied. For both peptides, a single class of binding sites accounted for the data with a mean (+/- SEM) Ka value of 0.23 +/- 0.123 X 10(8) liters/mol for AII and 0.68 X 10(8) liters/mol for des-Asp1-AII. The concentration at which unlabeled AII and des-Asp1-AII displaced 50% of the tracers (Kd) was similar to that at which they induced half-maximal stimulation of steroidogenesis (Kact). For AI and des-Asp1-AI, Kd greater than Kact. Analogs of AII or des-Asp1-AII with antagonistic properties upon steroidogenesis competed also with binding of the tracers. Corticotropin (ACTH) did not inhibit binding. Although ACTH stimulated the formation of cyclic AMP, none of the angiotensins with intrinsic activity did so. Calcium, but not potassium, appeared to potentiate the steroidogenic activity of AII. These data suggest that there is a single class of receptors for angiotensins and analogs in zona fasciculata. These receptors show characteristics that differentiate them from ACTH receptors in zona fasciculata or angiotensin receptors in zona glomerulosa cells. PMID:6264451
Safety, efficacy and efficiency of laser-assisted IVF in subfertile mutant mouse strains
Li, Ming-Wen; Kinchen, Kristy L; Vallelunga, Jadine M; Young, Diana L; Wright, Kaleb D K; Gorano, Lisa N; Wasson, Katherine; Lloyd, K C Kent
2013-01-01
In the present report we studied the safety, efficacy and efficiency of using an infrared laser to facilitate IVF by assessing fertilization, development and birth rates after laser-zona drilling (LZD) in 30 subfertile genetically modified (GM) mouse lines. We determined that LZD increased the fertilization rate four to ten times that of regular IVF, thus facilitating the derivation of 26 of 30 (86.7%) GM mouse lines. Cryopreserved two-cell stage embryos derived by LZD-assisted IVF were recovered and developed to blastocysts in vitro at the same rate as frozen–thawed embryos derived by regular IVF. Surprisingly after surgical transfer to pseudopregnant recipients the birth rate of embryos derived by LZD-assisted IVF was significantly lower than that of embryos derived by regular IVF. However this result could be completely mitigated by the addition of 0.25 M sucrose to the culture medium during LZD which caused the oocyte to shrink in volume relative to the perivitelline space. By increasing the distance from the laser target site on the zona pellucida, we hypothesize that the hyperosmotic effect of sucrose reduced the potential for laser-induced cytotoxic thermal damage to the underlying oocytes. With appropriate preparation and cautious application, our results indicate that LZD-assisted IVF is a safe, efficacious and efficient assisted reproductive technology for deriving mutant mouse lines with male factor infertility and subfertility caused by sperm–zona penetration defects. PMID:23315689
Takeo, Toru; Nakagata, Naomi
2011-11-01
Sperm cryopreservation is useful for the effective storage of genomic resources derived from genetically engineered mice. However, freezing the sperm of C57BL/6 mice, the most commonly used genetic background for genetically engineered mice, considerably reduces its fertility. We previously reported that methyl-beta-cyclodextrin dramatically improved the fertility of frozen/thawed C57BL/6 mouse sperm. Recently, it was reported that exposing sperm to reduced glutathione may alleviate oxidative stress in frozen/thawed mouse sperm, thereby enhancing in vitro fertilization (IVF); however, the mechanism underlying this effect is poorly understood. In the present study, we examined the combined effects of methyl-beta-cyclodextrin and reduced glutathione on the fertilization rate of IVF with frozen/thawed C57BL/6 mouse sperm and the characteristic changes in the zona pellucida induced by reduced glutathione. Adding reduced glutathione to the fertilization medium increased the fertilization rate. Methyl-beta-cyclodextrin and reduced glutathione independently increased fertilization rates, and their combination produced the strongest effect. We found that reduced glutathione increased the amount of free thiols in the zona pellucida and promoted zona pellucida enlargement. Finally, 2-cell embryos produced by IVF with the addition of reduced glutathione developed normally and produced live offspring. In summary, we have established a novel IVF method using methyl-beta-cyclodextrin during sperm preincubation and reduced glutathione during the IVF procedure to enhance fertility of frozen/thawed C57BL/6 mouse sperm.
Premer, Courtney; Lamondin, Courtney; Mitzey, Ann; Speth, Robert C.; Brownfield, Mark S.
2013-01-01
Angiotensin II increases blood pressure and stimulates thirst and sodium appetite in the brain. It also stimulates secretion of aldosterone from the adrenal zona glomerulosa and epinephrine from the adrenal medulla. The rat has 3 subtypes of angiotensin II receptors: AT1a, AT1b, and AT2. mRNAs for all three subtypes occur in the adrenal and brain. To immunohistochemically differentiate these receptor subtypes, rabbits were immunized with C-terminal fragments of these subtypes to generate receptor subtype-specific antibodies. Immunofluorescence revealed AT1a and AT2 receptors in adrenal zona glomerulosa and medulla. AT1b immunofluorescence was present in the zona glomerulosa, but not the medulla. Ultrastructural immunogold labeling for the AT1a receptor in glomerulosa and medullary cells localized it to plasma membrane, endocytic vesicles, multivesicular bodies, and the nucleus. AT1b and AT2, but not AT1a, immunofluorescence was observed in the anterior pituitary. Stellate cells were AT1b positive while ovoid cells were AT2 positive. In the brain, neurons were AT1a, AT1b, and AT2 positive, but glia was only AT1b positive. Highest levels of AT1a, AT1b, and AT2 receptor immunofluorescence were in the subfornical organ, median eminence, area postrema, paraventricular nucleus, and solitary tract nucleus. These studies complement those employing different techniques to characterize Ang II receptors. PMID:23573410
Dynamic regulation of sperm interactions with the zona pellucida prior to and after fertilisation.
Gadella, B M
2012-01-01
Recent findings have refined our thinking on sperm interactions with the cumulus-oocyte complex (COC) and our understanding of how, at the molecular level, the sperm cell fertilises the oocyte. Proteomic analyses has identified a capacitation-dependent sperm surface reordering that leads to the formation of functional multiprotein complexes involved in zona-cumulus interactions in several mammalian species. During this process, multiple docking of the acrosomal membrane to the plasma membrane takes place. In contrast with the dogma that the acrosome reaction is initiated when spermatozoa bind to the zona pellucida (ZP), it has been established recently that, in mice, the fertilising spermatozoon initiates its acrosome reaction during its voyage through the cumulus before it reaches the ZP. In fact, even acrosome-reacted mouse spermatozoa collected from the perivitelline space can fertilise another ZP-intact oocyte. The oviduct appears to influence the extracellular matrix properties of the spermatozoa as well as the COC. This may influence sperm binding and penetration of the cumulus and ZP, and, in doing so, increase monospermic while decreasing polyspermic fertilisation rates. Structural analysis of the ZP has shed new light on how spermatozoa bind and penetrate this structure and how the cortical reaction blocks sperm-ZP interactions. The current understanding of sperm interactions with the cumulus and ZP layers surrounding the oocyte is reviewed with a special emphasis on the lack of comparative knowledge on this topic in humans, as well as in most farm mammals.
Automation and Optimization of Multipulse Laser Zona Drilling of Mouse Embryos During Embryo Biopsy.
Wong, Christopher Yee; Mills, James K
2017-03-01
Laser zona drilling (LZD) is a required step in many embryonic surgical procedures, for example, assisted hatching and preimplantation genetic diagnosis. LZD involves the ablation of the zona pellucida (ZP) using a laser while minimizing potentially harmful thermal effects on critical internal cell structures. Develop a method for the automation and optimization of multipulse LZD, applied to cleavage-stage embryos. A two-stage optimization is used. The first stage uses computer vision algorithms to identify embryonic structures and determines the optimal ablation zone farthest away from critical structures such as blastomeres. The second stage combines a genetic algorithm with a previously reported thermal analysis of LZD to optimize the combination of laser pulse locations and pulse durations. The goal is to minimize the peak temperature experienced by the blastomeres while creating the desired opening in the ZP. A proof of concept of the proposed LZD automation and optimization method is demonstrated through experiments on mouse embryos with positive results, as adequately sized openings are created. Automation of LZD is feasible and is a viable step toward the automation of embryo biopsy procedures. LZD is a common but delicate procedure performed by human operators using subjective methods to gauge proper LZD procedure. Automation of LZD removes human error to increase the success rate of LZD. Although the proposed methods are developed for cleavage-stage embryos, the same methods may be applied to most types LZD procedures, embryos at different developmental stages, or nonembryonic cells.
Aquifer/aquitard interfaces: mixing zones that enhance biogeochemical reactions
NASA Astrophysics Data System (ADS)
McMahon, P. B.
2001-01-01
Several important biogeochemical reactions are known to occur near the interface between aquifer and aquitard sediments. These reactions include O2 reduction; denitrification; and Fe3+, SO42-, and CO2 (methanogenesis) reduction. In some settings, these reactions occur on the aquitard side of the interface as electron acceptors move from the aquifer into the electron-donor-enriched aquitard. In other settings, these reactions occur on the aquifer side of the interface as electron donors move from the aquitard into the electron-acceptor-enriched, or microorganism-enriched, aquifer. Thus, the aquifer/aquitard interface represents a mixing zone capable of supporting greater microbial activity than either hydrogeologic unit alone. The extent to which biogeochemical reactions proceed in the mixing zone and the width of the mixing zone depend on several factors, including the abundance and solubility of electron acceptors and donors on either side of the interface and the rate at which electron acceptors and donors react and move across the interface. Biogeochemical reactions near the aquifer/aquitard interface can have a substantial influence on the chemistry of water in aquifers and on the chemistry of sediments near the interface. Résumé. Il se produit au voisinage de l'interface entre les aquifères et les imperméables plusieurs réactions biogéochimiques importantes. Il s'agit des réactions de réduction de l'oxygène, de la dénitrification et de la réduction de Fe3+, SO42- et CO2 (méthanogenèse). Dans certaines situations, ces réactions se produisent du côté imperméable de l'interface, avec des accepteurs d'électrons qui vont de l'aquifère vers l'imperméable riche en donneurs d'électrons. Dans d'autres situations, ces réactions se produisent du côté aquifère de l'interface, avec des donneurs d'électrons qui se déplacent de l'imperméable vers l'aquifère riche en accepteurs d'électrons ou en microorganismes. Ainsi, l'interface aquifère/imperméable constitue une zone de mélange capable de supporter une plus grande activité microbienne que chacune des deux unités hydrogéologiques seules. L'extension des réactions biogéochimiques dans la zone de mélange et la largeur de cette zone dépendent de plusieurs facteurs, dont l'abondance et la solubilité des accepteurs et des donneurs d'électrons de chaque côté de l'interface, et le taux de réaction et de déplacement des accepteurs et des donneurs d'électrons au travers de cette interface. Les réactions biogéochimiques au voisinage de l'interface aquifère/imperméable peuvent avoir une influence appréciable sur le chimisme de l'eau des aquifères et sur celui des sédiments au niveau de l'interface. Resúmen. Es conocido que varias reacciones biogeoquímicas de importancia pueden tener lugar cerca de la interfaz entre los sedimentos de un acuífero y de un acuitardo. Entre ellas, destaca la reducción del O2, la denitrificación, y la reducción del Fe+3, SO4-2 y CO2 (metanogénesis). En algunos casos, estas reacciones se producen en la región cercana al acuitardo, ya que los dadores de electrones se mueven desde éste hacia el acuífero, el cual está enriquecido en aceptores de electrones o en microorganismos. Así, la interfaz acuífero/acuitardo constituye una zona de mezcla que es capaz de sustentar una actividad microbiana mayor que cualquier unidad hidrogeológica por sí misma. El alcance de las reacciones biogeoquímicas en la zona de mezcla y el ancho de esta zona de mezcla depende de varios factores, como la abundancia y la solubilidad de los aceptores y dadores de electrones en ambas caras de la interfaz y la velocidad a la que los aceptores y dadores de electrones reaccionan y se mueven a través de la interfaz. Las reacciones biogeoquímicas cerca de la interfaz acuífero/acuitardo pueden tener una influencia substancial en la hidroquímica de los acuíferos y en la química de los sedimentos cerca de la superficie.
2012-01-01
Introduction International evidence indicates consistently lower rates of access and use of healthcare by international immigrants. Factors associated with this phenomenon vary significantly depending on the context. Some research into the health of immigrants has been conducted in Latin America, mostly from a qualitative perspective. This population-based study is the first quantitative study to explore healthcare provision entitlement and use of healthcare services by immigrants in Chile and compare them to the Chilean-born. Methods Data come from the nationally representative CASEN (Socioeconomic characterization of the population in Chile) surveys, conducted in 2006 and 2009. Self-reported immigrants were compared to the Chilean-born, by demographic characteristics (age, sex, urban/rural, household composition, ethnicity), socioeconomic status (SES: education, household income, contractual status), healthcare provision entitlement (public, private, other, none), and use of primary services. Weighted descriptive, stratified and adjusted regression models were used to analyse factors associated with access to and use of healthcare. Results There was an increase in self-reported immigrant status and in household income inequality among immigrants between 2006 and 2009. Over time there was a decrease in the rate of immigrants reporting no healthcare provision and an increase in reporting of private healthcare provision entitlement. Compared to the Chilean-born, immigrants reported higher rates of use of antenatal and gynaecological care, lower use of well-baby care, and no difference in the use of Pap smears or the number of attentions received in the last three months. Immigrants in the bottom income quintile were four times more likely to report no healthcare provision than their equivalent Chilean-born group (with different health needs, i.e. vertical inequity). Disabled immigrants were more likely to have no healthcare provision compared to the disabled Chilean-born (with similar health needs, i.e. horizontal inequity). Factors associated with immigrants’ access to, and use of, healthcare were sex, urban/rural status, education and country of origin. Conclusion There were significant associations between SES, and access to and use of healthcare among immigrants in Chile and a higher prevalence of no health care provision entitlement among poor and disabled immigrants compared to the Chilean-born. Changing associations between access and use of healthcare and SES among immigrants in Chile over time may reflect changes in their socio-demographic composition or in the survey methodology between 2006 and 2009. Resumen Introducción La evidencia internacional indica menor acceso y uso de servicios de salud por parte de inmigrantes, pero sus factores desencadenantes varían significativamente dependiendo del contexto. Algunas investigaciones se han desarrollado en este tema en América Latina, desde una perspectiva cualitativa. Este estudio cuantitativo exploró el auto-reporte de acceso y uso de servicios de salud de inmigrantes en Chile y los comparó con la población chilena. Métodos Análisis secundario de datos de encuesta nacional CASEN 2006 y 2009. Inmigrantes fueron comparados con chilenos en características demográficas (edad, sexo, urbano/rural, composición del hogar, etnia), estatus socioeconómico (educación, ingreso, situación contractual), tipo de previsión (pública, privada, otra, ninguna), y uso de varios servicios de atención primaria. Análisis descriptivo, estratificado, y modelos de regresión ponderados para entender factores asociados al acceso y uso de servicios de salud en STATA 11.0. Resultados Se observó un aumento de reporte de inmigrantes y de la desigualdad en el ingreso de inmigrantes entre 2006 y 2009. Hubo una disminución en la tasa de inmigrantes sin previsión y un aumento en el acceso al sistema privado. Los inmigrantes usaron más frecuentemente la atención prenatal y ginecológica, y menos la atención del niño sano. No hubo diferencia en el uso de citología vaginal o el número total de atenciones recibidas en comparación con los chilenos. Los inmigrantes en el quintil inferior de ingresos reportaron 4 veces más la ausencia de prestación de salud que los chilenos (inequidad vertical). Similares resultados se observaron al comparar inmigrantes con discapacidad con chilenos con discapacidad (inequidad horizontal). Los factores asociados con el acceso y uso del servicio de salud por parte de los inmigrantes fueron el sexo, urbano/rural, educación y país de origen. Conclusión Se observó una asociación significativa entre estatus socioeconomico, migración y acceso y uso de asistencia sanitaria. Los resultados de este estudio pueden deberse a verdaderos cambios en la composición de los inmigrantes y sus patrones de uso del sistema de salud chileno, pero también pueden deberse a cambios en la metodología y recolección de datos entre encuestas 2006 y 2009. Este aspecto requiere mayor análisis y debate en la región. PMID:23158113
NASA Astrophysics Data System (ADS)
Jackson, R. E.
The migration, dissolution, and subsequent fate of spilled chlorinated solvents in the urban alluvial valleys of the southwestern U.S. appear to be governed by a unique set of hydrogeologic and geochemical processes occurring within terrigeneous clastic depositional systems. The alluvial and lacustrine fill of the basins, the trapping of solvents in fine-grained sediments beneath the urbanized valley centers, the oxic conditions typical of the deeper alluvium, and the contaminant-transport patterns produced by large-scale basin pumping combine to produce long aqueous-phase plumes derived from the dissolution of trapped chlorinated solvents. Although of limited aqueous solubility, these dense solvents are sufficiently mobile and soluble in the southwestern alluvial valleys to have produced aqueous plumes that have migrated several kilometers through the deeper alluvium and have contaminated valuable water-supply well fields in California, Arizona, and New Mexico. The typical length of these plumes and the presence of oxic groundwater indicate that it is unlikely that natural attenuation will be a practical remedial option in the southwestern alluvial valleys or in other alluvial systems in which similar hydrogeologic and geochemical conditions exist. Résumé La migration, la dissolution et l'évolution consécutive des rejets de solvants chlorés dans les vallées alluviales du sud-ouest des États-Unis paraissent déterminées par un même ensemble de processus hydrogéologiques et géochimiques intervenant dans des formations de dépôts clastiques terrigènes. Les remplissages alluviaux et lacustres des bassins, le piégeage des solvants par des sédiments fins sous les centres des vallées urbanisées, les conditions oxiques typiques des alluvions plus profondes et les types de transport de contaminants provoqués par le pompage à l'échelle du bassin se combinent pour produire des panaches, étendus dans la phase aqueuse, provenant de la dissolution de solvants chlorés piégés. Malgré leur faible solubilité dans l'eau, ces solvants denses sont suffisamment mobiles et solubles pour avoir produit, dans le sud-ouest des vallées alluviales, des panaches aqueux qui ont migré de plusieurs kilomètres dans les alluvions plus profondes et ont contaminé des champs captants pour l'eau potable en Californie, en Arizona et au Nouveau-Mexique. La longueur de ces panaches et la présence d'eau souterraine en conditions oxiques indiquent qu'il est peu probable que la décroissance naturelle soit un recours pratique de décontamination dans les vallées alluviales du sud-ouest ou dans d'autres systèmes alluviaux dans lesquels existent des conditions hydrogéologiques et géochimiques semblables. Resumen La migración, disolución y transporte de compuestos clorados en valles aluviales urbanos del sudoeste de los Estados Unidos de América parecen estar gobernados por un conjunto único de procesos hidrogeológicos y geoquímicos que tienen lugar en los depósitos clásticos. El relleno aluvial y lacustre de las cuencas, la inmovilización de los solutos en sedimentos de grano fino bajo las zonas urbanizadas, los condiciones óxicas típicas del aluvial profundo y las direcciones de transporte regidas por los fuertes bombeos en las cuencas se combinan para producir grandes penachos en fase acuosa procedentes de la disolución de los compuestos clorados atrapados en el medio. Aunque la solubilidad de estos compuestos clorados densos es pequeña, es suficiente para producir penachos que en algunos casos se han desplazado varios kilómetros a través del aluvial profundo y han llegado a contaminar zonas de extracción muy productivas en California, Arizona y Nuevo México. La longitud de estos penachos y la presencia de agua subterránea oxidante indican que es improbable que la degradación natural sea un buen método de limpieza de estos acuíferos o de otros sistemas aluviales que presenten características hidrogeológicas y geoquímicas semejantes.
Grilli, Mariano Pablo; Fachinetti, Romina
2017-06-01
In Córdoba province, central Argentina, there is an area of introduced pine trees, in which an invading Cerambycid, Arhopalus rusticus (L.), was detected in this region for the first time in 2006. The species has since expanded its range until it now occupies the whole area. Arhopalus rusticus is a common species in pine forests of the northern hemisphere. In this paper, we analyze how sex and mating status affects flight performance and the potential distribution of this species. The study was performed with individuals collected from introduced pine forests in the center-west of Córdoba Province (Argentina). The dispersal capability of A. rusticus was determined by measuring flight speed and distance traveled by recently emerged mated and unmated A. rusticus in flight mills. Data of preflight body weight, postflight body weight, body length, and elytron size were obtained from the individuals that were flown in the flight mill. We found that females had a greater body length, weighed more, had longer elytra, and were stronger flyers than males. We also found that mated individuals flew faster and longer distances than unmated individuals, and consumed a smaller fraction of their body weight. A positive ratio was observed between elytra size and flight speed. A map of males' and females' dispersal distances was produced for the study region, using the adjusted dispersal distance distribution of males and females. The flight performance showed that, as females disperse after copulation, they increase the chances of establishing the species in unoccupied areas.En la provincia de Córdoba, Argentina, hay una importante área de pinos implantados. En esta región durante el año 2006 se detectó por primera vez a Arhopalus rusticus (L.), un Cerambycidae invasor. A. rusticus es una especie común en los bosques de pino del hemisferio norte. En este trabajo analizamos de qué manera el sexo y el estado de apareamiento afectan el desempeño de vuelo y la distribución potencial de esta especie. Utilizamos individuos recolectados de los bosques de pino implantados en la región centro oeste de la provincia de Córdoba (Argentina). La capacidad de dispersión de Arhopalus rusticus se determinó haciendo volar individuos recién emergidos en un molino de vuelo. Se registró el peso previo y posterior al vuelo, el largo del cuerpo y el tamaño del élitro. Las hembras fueron mejores voladoras, más largas, más pesadas, con élitros más largos que los machos. Observamos diferencias entre el potencial de dispersión dependiendo del estado de apareamiento de los individuos. Los individuos apareados volaron más rápido y mayores distancias que los individuos no apareados y consumieron una menor fracción de su peso corporal. Se observó una relación positiva entre el tamaño del élitro y la velocidad de vuelo. Se generó un mapa de las distancias de dispersión potencial de los machos y de las hembras para la región de estudio utilizando las distribuciones de las distancias obtenidas del molino de vuelo. La dispersión post copulación incrementa las chances de que la especie se establezca en zonas no ocupadas. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
77 FR 33766 - Notice of Public Meeting; Wyoming Resource Advisory Council
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-07
... the BLM's wild horse partnership with Friends of a Legacy and Marathon Oil, water projects, porcine zona pellucida and the overall wild horse program; a RAC business session; and a presentation on fire...
Unresolved issues in mammalian fertilization.
Olds-Clarke, Patricia
2003-01-01
This review considers the role of the sperm in fertilization, addressing areas of misunderstanding and unfounded assumptions and taking particular advantage of the large body of data resulting from work with rodent species in vitro. Considerable attention is given to the appropriate use and interpretation of assays for capacitation, acrosomal exocytosis, hyperactivation, and sperm protein phosphorylation, as well as tests for sperm-zona and sperm-oocyte membrane interactions. The lack of general agreement on the means of sperm adhesion to and penetration of the zona pellucida is addressed, and the need for new approaches to this problem is pointed out. Some molecular advances in our understanding of specific steps in the process of fertilization are discussed in the context of intact cell-matrix and cell-cell interaction. This review should provide practical information for researchers just beginning the study of fertilization and interesting but not widely known observations to stimulate new ideas in experienced scientists.
Rapid binge-like eating and body weight gain driven by zona incerta GABA neuron activation.
Zhang, Xiaobing; van den Pol, Anthony N
2017-05-26
The neuronal substrate for binge eating, which can at times lead to obesity, is not clear. We find that optogenetic stimulation of mouse zona incerta (ZI) γ-aminobutyric acid (GABA) neurons or their axonal projections to paraventricular thalamus (PVT) excitatory neurons immediately (in 2 to 3 seconds) evoked binge-like eating. Minimal intermittent stimulation led to body weight gain; ZI GABA neuron ablation reduced weight. ZI stimulation generated 35% of normal 24-hour food intake in just 10 minutes. The ZI cells were excited by food deprivation and the gut hunger signal ghrelin. In contrast, stimulation of excitatory axons from the parasubthalamic nucleus to PVT or direct stimulation of PVT glutamate neurons reduced food intake. These data suggest an unexpected robust orexigenic potential for the ZI GABA neurons. Copyright © 2017, American Association for the Advancement of Science.
Identification of a ZP3-binding protein on acrosome-intact mouse sperm by photoaffinity crosslinking
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bleil, J.D.; Wassarman, P.M.
1990-07-01
During the process of fertilization in mammals, sperm bind in a relatively species-specific manner to the zona pellucida (ZP) of ovulated eggs. ZP3, a glycoprotein found in the mouse egg zona pellucida, serves as receptor for sperm during gamete adhesion. We report here that a Mr 56,000 protein found on mouse sperm has properties expected for a sperm component that recognizes and binds to ZP3. This sperm protein is radiolabeled preferentially by a photoactivatable heterobifunctional crosslinker (Denny-Jaffee reagent) covalently linked to purified ZP3, binds very tightly to ZP3-affinity columns, and is localized to heads of acrosome-intact but not acrosome-reacted sperm.more » These and other findings suggest that this protein may be a ZP3-binding protein that, together with the sperm receptor, supports species-specific binding of mouse sperm to unfertilized eggs.« less
Lagutina, Irina; Lazzari, Giovanna; Duchi, Roberto; Colleoni, Silvia; Ponderato, Nunzia; Turini, Paola; Crotti, Gabriella; Galli, Cesare
2005-10-01
The objective of the present work was to investigate and clarify the factors affecting the efficiency of somatic cell nuclear transfer (NT) in the horse, including embryo reconstruction, in vitro culture to the blastocyst stage, embryo transfer, pregnancy monitoring and production of offspring. Matured oocytes, with zona pellucida or after zona removal, were fused to cumulus cells, granulosa cells, and fetal and adult fibroblasts, and fused couplets were cultured in vitro. Blastocyst development to Day 8 varied significantly among donor cells (from 1.3% to 16%, P < 0.05). In total, 137 nuclear transfer-embryos were transferred nonsurgically to 58 recipient mares. Pregnancy rate after transfer of NT-embryos derived from adult fibroblasts from three donor animals was 24.3% (9/37 mares transferred corresponding to 9/101 blastocysts transferred), while only 1/18 (5.6%) of NT-blastocysts derived from one fetal cell line gave rise to a pregnancy (corresponding to 1/33 blastocysts transferred). Overall, seven pregnancies were confirmed at 35 days, and two went to term delivering two live foals. One foal died 40 h after birth of acute septicemia while the other foal was healthy and is currently 2 months old. These results indicate that (a) the zona-free method allows high fusion rate and optimal use of equine oocytes, (b) different donor cell cultures have different abilities to support blastocyst development, (c) blastocyst formation rate does not correlate with pregnancy fate and (d) healthy offspring can be obtained by somatic cell nuclear transfer in the horse.
Regulation of aldosterone secretion by mineralocorticoid receptor-mediated signaling.
Chong, Cherish; Hamid, Anis; Yao, Tham; Garza, Amanda E; Pojoga, Luminita H; Adler, Gail K; Romero, Jose R; Williams, Gordon H
2017-03-01
We posit the existence of a paracrine/autocrine negative feedback loop, mediated by the mineralocorticoid receptor (MR), regulating aldosterone secretion. To assess this hypothesis, we asked whether altering MR activity in zona glomerulosa (ZG) cells affects aldosterone production. To this end, we studied ex vivo ZG cells isolated from male Wistar rats fed chow containing either high (1.6% Na + (HS)) or low (0.03% Na + (LS)) amount of sodium. Western blot analyses demonstrated that MR was present in both the ZG and zona fasciculata/zona reticularis (ZF/ZR/ZR). In ZG cells isolated from rats on LS chow, MR activation by fludrocortisone produced a 20% and 60% reduction in aldosterone secretion basally and in response to angiotensin II (ANGII) stimulation, respectively. Corticosterone secretion was increased in these cells suggesting that aldosterone synthase activity was being reduced by fludrocortisone. In contrast, canrenoic acid, an MR antagonist, enhanced aldosterone production by up to 30% both basally and in response to ANGII. Similar responses were observed in ZG cells from rats fed HS. Modulating glucocorticoid receptor (GR) activity did not alter aldosterone production by ZG cells; however, altering GR activity did modify corticosterone production from ZF/ZR/ZR cells both basally and in response to adrenocorticotropic hormone (ACTH). Additionally, activating the MR in ZF/ZR/ZR cells strikingly reduced corticosterone secretion. In summary, these data support the hypothesis that negative ultra-short feedback loops regulate adrenal steroidogenesis. In the ZG, aldosterone secretion is regulated by the MR, but not the GR, an effect that appears to be secondary to a change in aldosterone synthase activity. © 2017 Society for Endocrinology.
Louros, Nikolaos N.; Iconomidou, Vassiliki A.; Giannelou, Polina; Hamodrakas, Stavros J.
2013-01-01
Zona pellucida (ZP) is an extracellular matrix surrounding and protecting mammalian and fish oocytes, which is responsible for sperm binding. Mammalian ZP consists of three to four glycoproteins, called ZP1, ZP2, ZP3, ZP4. These proteins polymerize into long interconnected filaments, through a common structural unit, known as the ZP domain, which consists of two domains, ZP-N and ZP-C. ZP is related in function to silkmoth chorion and in an evolutionary fashion to the teleostean fish chorion, also fibrous structures protecting the oocyte and embryo, that both have been proven to be functional amyloids. Two peptides were predicted as ‘aggregation-prone’ by our prediction tool, AMYLPRED, from the sequence of the human ZP1-N domain. Here, we present results from transmission electron microscopy, X-ray diffraction, Congo red staining and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR FT-IR), of two synthetic peptide-analogues of these predicted ‘aggregation-prone’ parts of the human ZP1-N domain, that we consider crucial for ZP protein polymerization, showing that they both self-assemble into amyloid-like fibrils. Based on our experimental data, we propose that human ZP (hZP) might be considered as a novel, putative, natural protective amyloid, in close analogy to silkmoth and teleostean fish chorions. Experiments are in progress to verify this proposal. We also attempt to provide insights into ZP formation, proposing a possible model for hZP1-N domain polymerization. PMID:24069181
Hino, Toshiaki; Muro, Yuko; Tamura-Nakano, Miwa; Okabe, Masaru; Tateno, Hiroyuki; Yanagimachi, Ryuzo
2016-09-01
Although 90%-100% of mouse oocytes can be fertilized in vitro with capacitated spermatozoa within 1 h after insemination, oocytes within the oviduct are fertilized one by one over a period of several hours. In vitro experiments showed that both acrosome-intact and acrosome-reacted spermatozoa entered the cumulus oophorus, but that acrosome-reacted spermatozoa reached the surface of oocytes more readily than acrosome-intact spermatozoa. During the period of fertilization within the oviduct, acrosome-reacted spermatozoa were seen throughout the isthmus, but with higher incidence in the upper than in the mid- and lower segments of the isthmus. Very few spermatozoa were present in the ampulla, and almost all were acrosome reacted. Although the cumulus oophorus and zona pellucida are known to be able to induce or facilitate the acrosome reaction of spermatozoa, this picture makes it likely that almost all fertilizing mouse spermatozoa within the oviduct begin to react before ascending from the isthmus to the ampulla. We witnessed a reacted spermatozoon that stayed on the zona pellucida of a fertilized oocyte for a while; it then moved out of the cumulus before reaching the zona pellucida of the nearby unfertilized oocyte. We noted that only a few spermatozoa migrate from the isthmus to the ampulla during the progression of fertilization, and this must be one of the reasons why we do not see many spermatozoa swarming around a single oocyte during in vivo fertilization. © 2016 by the Society for the Study of Reproduction, Inc.
SLXL1, a novel acrosomal protein, interacts with DKKL1 and is involved in fertilization in mice.
Zhuang, Xin-jie; Hou, Xiao-jun; Liao, Shang-Ying; Wang, Xiu-Xia; Cooke, Howard J; Zhang, Ming; Han, Chunsheng
2011-01-01
Spermatogenesis is a complex cellular developmental process which involves diverse families of genes. The Xlr (X-linked, lymphocyte regulated) family includes multiple members, only a few of which have reported functions in meiosis, post-meiotic maturation, and fertilization of germ cells. Slx-like1 (Slxl1) is a member of the Xlr family, whose expression and function in spermatogenesis need to be elucidated. The mRNA and protein expression and localization of Slxl1 were investigated by RT-PCR, Western blotting and immunohistochemistry in different tissues and at different stages of spermatogenesis. The interacting partner of SLXL1 was examined by co-immunoprecipitation and co-localization. Assessment of the role of SLXL1 in capacitation, acrosome reaction, zona pellucida binding/penetration, and fertilization was carried out in vitro using blocking antisera. The results showed that Slxl1 mRNA and protein were specifically expressed in the testis. SLXL1 was exclusively located in the acrosome of post-meiotic germ cells and interacts with DKKL1 (Dickkopf-like1), which is an acrosome-associated protein and plays an important role in fertilization. The rates of zona pellucida binding/penetration and fertilization were significantly reduced by the anti-SLXL1 polyclonal antiserum. SLXL1 is the first identified member of the XLR family that is associated with acrosome and is involved in zona pellucid binding/penetration and subsequent fertilization. These results, together with previous studies, suggest that Xlr family members participate in diverse processes from meiosis to fertilization during spermatogenesis.
Ferrer, Marvin; Rodriguez, Hilma; Zara, Lindsay; Yu, Yang; Xu, Wei; Oko, Richard
2012-09-01
Sperm-zona pellucida (ZP) penetration during fertilization is a process that most likely involves enzymatic digestion of this extracellular coat by spermatozoa. Since the inner acrosomal membrane (IAM) is the leading edge of spermatozoa during penetration and proteins required for secondary binding of sperm to the zona are present on it, the IAM is the likely location of these enzymes. The objectives of this study were to identify and characterize proteinases present on the IAM, confirm their localization and provide evidence for their role in fertilization. Gelatin zymography of detergent extracts of the IAM revealed bands of enzymatic activity identified as serine and matrix metallo-proteinases (MMPs). Specific inhibitors to MMPs revealed that MMP activity was due to MMP2. Immunoblotting determined that the serine protease activity on the zymogram was due to acrosin and also confirmed the MMP2 activity. Immunogold labeling of spermatozoa at the electron microscope level showed that acrosin and MMP2 were confined to the apical and principal segments of the acrosome in association with the IAM, confirming our IAM isolation technique. Immunohistochemical examination of acrosin and MMP2 during spermiogenesis showed that both proteins originate in the acrosomic granule during the Golgi phase and later redistribute to the acrosomal membrane. Anti-MMP2 antibodies and inhibitors incorporated into in vitro fertilization media significantly decreased fertilization rates. This is the first study to demonstrate that MMP2 and acrosin are associated with the IAM and introduces the possibility of their cooperation in enzymatic digestion of the ZP during penetration.
Epididymal protein CRISP1 plays different roles during the fertilization process.
Cohen, Débora J; Maldera, Julieta A; Vasen, Gustavo; Ernesto, Juan I; Muñoz, Mariana Weigel; Battistone, María A; Cuasnicú, Patricia S
2011-01-01
Rat epididymal CRISP1, the first described member of the evolutionarily conserved Cysteine-RIch Secretory Protein (CRISP) family, is expressed in the proximal regions of the epididymis and associates with the sperm during epididymal transit. Evidence indicates the existence of 2 populations of CRISP1 in spermatozoa: a major one, loosely bound, which is released during capacitation and, therefore, proposed as a decapacitating factor; and a minor one, strongly associated with spermatozoa that remains on the cells after capacitation and is proposed to participate in gamete interaction. Originally localized to the dorsal region of capacitated sperm, CRISP1 migrates to the equatorial segment with capacitation and acrosome reaction. Consistent with these localizations, in vitro fertilization experiments support the involvement of CRISP1 in the first step of sperm-zona pellucida (ZP) interaction and subsequent gamete fusion through its interaction with egg-complementary sites. The potential roles of CRISP1 in capacitation and fertilization have been further supported by the finding that capacitated spermatozoa from CRISP1 "knockout" animals exhibit low levels of protein tyrosine phosphorylation and have an impaired ability to fertilize zona-intact and zona-free eggs in vitro. Moreover, recent evidence from mutant spermatozoa reveals that CRISP1 mediates the stage of sperm binding to the ZP. Altogether, these observations support the view that CRISP1 is a multifunctional protein playing different roles during fertilization through its different associations with and localizations on spermatozoa. We believe these results contribute to a better understanding of the molecular mechanisms involved in both the fertilization process and the acquisition of sperm-fertilizing ability that occurs during epididymal maturation.
Human homolog of the mouse sperm receptor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chamberlin, M.E.; Dean, J.
1990-08-01
The human zona pellucida, composed of three glycoproteins (ZP1, ZP2, and ZP3), forms an extracellular matrix that surrounds ovulated eggs and mediates species-specific fertilization. The genes that code for at least two of the zona proteins (ZP2 and ZP3) cross-hybridize with other mammalian DNA. The recently characterized mouse sperm receptor gene (Zp-3) was used to isolate its human homolog. The human homolog spans {approx}18.3 kilobase pairs (kbp) (compared to 8.6 kbp for the mouse gene) and contains eight exons, the sizes of which are strictly conserved between the two species. Four short (8-15 bp) sequences within the first 250 bpmore » of the 5{prime} flanking region in the human Zp-3 homolog are also present upstream of mouse Zp-3. These elements may modulate oocyte-specific gene expression. By using the polymerase chain reaction, a full-length cDNA of human ZP3 was isolated from human ovarian poly(A){sup +} RNA and used to deduce the structure of human ZP3 mRNA. Certain features of the human and mouse ZP3 transcripts are conserved. Both have unusually short 5{prime} and 3{prime} untranslated regions, both contain a single open reading frame that is 74% identical, and both code for 424 amino acid polypeptides that are 67% the same. The similarity between the two proteins may define domains that are important in maintaining the structural integrity of the zona pellucida, while the differences may play a role in mediating the species-specific events of mammalian fertilization.« less
Uçar, Ahmet; Öner, Nergiz; Özek, Gülcihan; Çetinçakmak, Mehmet Güli; Abuhandan, Mahmut; Yıldırım, Ali; Kaya, Cemil; Ünverdi, Sena; Emeksiz, Hamdi Cihan; Yılmaz, Yasin; Yetim, Aylin
2016-07-01
The variable presence of adrenal insufficiency (AI) due to hypocortisolemia (HC) in patients with thalassemia is well established; however, the prevalence of adrenocortical hypofunction (ACH) in the zona glomerulosa and zona reticularis of the adrenal cortex is unknown. To establish the prevalence of ACH, we examined the cortisol response to 1-µg and 250-µg ACTH tests, plasma aldosterone (A)/plasma renin activity (PRA) ratio, and serum dehydroepiandrosterone sulfate (DHEAS) levels in a large cohort of patients with thalassemia, and to investigate the impact of total body iron load (TBIL) on adrenocortical function. The setting used was University hospital and government-based tertiary care center. One hundred twenty-one (52 females) patients with β-thalassemia major (β-TM) and 72 healthy peers (38 females) were enrolled. The patients underwent a 250-µg cosyntropin test if their peak cortisol was <500 nmol/L in a 1-µg cosyntropin test. Magnetic resonance imaging (MRI) was performed to assess the MRI-based liver iron content and cardiac MRI T2* iron. The associations between ACH and TBIL were investigated. The patients with thalassemia had lower ACTH, cortisol, DHEAS, and A/PRA values compared with the controls (p < 0.001). Thirty-nine patients (32.2 %) had HC [primary (n = 1), central (n = 36), combined (n = 2)], and 47 (38.8 %) patients had reduced DHEAS levels; 29 (24.0 %) patients had reduced A/PRA ratios. Forty-six (38.0 %) patients had hypofunction in one of the adrenal zones, 26 (21.5 %) had hypofunction in two adrenal zones, and 9 (7.4 %) had hypofunction in all three zones. Patient age and TBIL surrogates were significant independent parameters associated with ACH. Cardiac MRI T2* iron was the only significant parameter that predicted the severity of ACH at a cut-off of 20.6 ms, with 81 % sensitivity and 78 % specificity. Patients with thalassemia have a high prevalence of AI due to HC and zona glomerulosa and zona reticularis hypofunction. TBIL surrogates can predict ACH, but cardiac iron was the only surrogate that was adequately sensitive to predict the severity of ACH.
Rural Puerto Rican women's views on children's oral health: a qualitative community-based study.
López del Valle, Lydia M; Riedy, Christine A; Weinstein, Phil
2005-01-01
The purpose of this study was to examine women's views on beliefs, preferences, and behaviors relevant to children's oral health. Women of childbearing age and mothers of women of childbearing age were recruited from 2 rural Puerto Rican communities to participate in 24 focus groups. One hundred fifty women participated. Participants were asked about their awareness and knowledge of childhood decay and their child-feeding and oral care attitudes and practices. Analysis consisted of a comprehensive content review of participant's responses. Participants used a variety of infant and toddler feeding practices, including breastfeeding and prolonged bottle use. Children progressed through feeding stages based on mother's experience, older relatives' advice, and child readiness. Grandmothers were considered trusted and reliable sources of information. Many believed that dental disease did not affect infants and were unaware of el síndrome del biberón (baby bottle tooth decay, SIB). Participants believed that decay was caused by too much sugar and prolonged bottle use and only affected children. Dental visits were rare in very young children, unless conspicuous decay or pain was present. Mothers' dental experiences influenced seeking children's preventive and treatment visits. This study highlights caregivers' perceptions, which are inconsistent with maximizing children's oral health. This information can be used to develop culturally appropriate, community based oral health programs.
Karan, Abraar; Chapman, Gretchen B; Galvani, Alison
2012-01-01
Intestinal parasitic infections cause one of the largest global burdens of disease. To identify possible areas for interventions, a structured questionnaire addressing knowledge, attitude, and practice regarding parasitic infections as well as the less studied role of culture and resource availability was presented to mothers of school-age children in rural communities around San Juan del Sur, Nicaragua. We determined that access to resources influenced knowledge, attitude, and behaviors that may be relevant to transmission of parasitic infections. For example, having access to a clinic and prior knowledge about parasites was positively correlated with the practice of having fencing for animals, having fewer barefoot children, and treating children for parasites. We also found that cultural beliefs may contribute to parasitic transmission. Manifestations of machismo culture and faith in traditional medicines conflicted with healthy practices. We identified significant cultural myths that prevented healthy behaviors, including the beliefs that cutting a child's nails can cause tetanus and that showering after a hot day caused sickness. The use of traditional medicine was positively correlated with the belief in these cultural myths. Our study demonstrates that the traditional knowledge, attitude, and practice model could benefit from including components that examine resource availability and culture.
Biotransformation of pesticides in saturated-zone materials
NASA Astrophysics Data System (ADS)
Hoyle, Blythe L.; Arthur, Ellen L.
Many studies have been conducted to evaluate pesticide contamination of groundwater in the United States, but investigations of pesticide biotransformation in saturated zones are much less numerous than in surface soils. Because results of studies using soils are not directly applicable to the subsurface, the purpose of this paper is to illustrate examples of pesticide biotransformation in saturated-zone materials. Although it must be considered with caution, the US Environmental Protection Agency's (EPA) "Pesticides in Ground Water Database" was used to focus the discussion on the biotransformation potential of dibromoethane (EDB), atrazine, acetanilide herbicides, and aldicarb, all of which have been detected in groundwater in the United States. Results of more than two dozen studies indicate that a biotransformation potential for these pesticides exists in saturated-zone materials, although for any given pesticide substantial differences in biotransformation occurred. These variations were due both to differences in experimental methods and to heterogeneities in the subsurface materials under investigation. However, because biotransformation mechanisms were not well investigated, it is generally not possible to extrapolate predictions of biotransformation potential beyond the specific sites investigated. These results highlight the need to better understand microbial genetic regulation of biotransformation processes so that genetic information may be effectively incorporated into future investigations of biotransformation potential in the subsurface. Résumé De nombreuses études ont été réalisées pour évaluer le degré de pollution des aquifères par les pesticides aux États-Unis, mais les recherches concernant la biotransformation des pesticides dans les eaux souterraines sont beaucoup moins nombreuses que dans les sols. Du fait que les résultats des études concernant les sols ne sont pas directement applicables au milieu souterrain, le propos de cet article est d'illustrer par des exemples la biotransformation des pesticides dans les nappes. Bien qu'il faille la considérer avec précaution, la base de données sur les pesticides dans les eaux souterraines de l'Agence américaine pour la protection de l'environnement a été utilisée pour centrer la discussion sur le potentiel de biotransformation du dibromoéthane (EDB), de l'atrazine, des désherbants acétanildés et de l'aldicarb, qui tous ont été détectés dans les nappes des États-Unis. Les résultats de plus de deux douzaines d'études indiquent qu'il existe un potentiel de biotransformation de ces pesticides dans les nappes, bien qu'entre chacun de ces pesticides il existe des différences très nettes dans la biotransformation. Ces variations sont en fait dues à la fois à des différences dans les méthodes expérimentales et dans les hétérogénéités dans les matériaux étudiés. Cependant, parce que les mécanismes de la biotransformation ne sont pas bien étudiés, il est en général impossible d'extrapoler les prédictions du potentiel de biotransformation à des sites d'étude spécifiques. Ces résultats soulignent la nécessité de mieux comprendre la régulation génétique microbienne des processus de biotransformation, pour que l'information génétique puisse être efficacement prise en compte dans les futures recherches sur le potentiel de biotransformation dans le sous-sol. Resumen Se han llevado a cabo un gran número de estudios para evaluar la contaminación por pesticidas en los acuíferos de los Estados Unidos de América. Sin embargo, las investigaciones sobre biotransformación de pesticidas en la zona saturada son mucho menos numerosas que en suelos. Como los resultados obtenidos en suelos no son directamente transladables a la zona saturada, el objetivo de este artículo es mostrar ejemplos de biotransformación de pesticidas en la zona saturada. Aunque debe tomarse con cautela, la base de datos "Pesticides in Ground Water Database (Base de Datos de Pesticidas en Aguas Subterráneas)" perteneciente a la US EPA (Agencia de Protección Ambiental de los EEUU) se usó para centrar la discusión en la biotransformación potencial de diversos compuestos orgánicos detectados en diversos acuíferos de los EEUU. Los resultados de más de dos docenas de estudios indican que la biotransformación potencial de estos pesticidas en la zona saturada es posible, aunque para un pesticida dado pueden presentarse grandes diferencias, debidas tanto a diferencias en los métodos experimentales como a la heterogeneidad de los materiales. Sin embargo, no es posible en general extrapolar las predicciones de biotransformación potencial más allá de las zonas específicas estudiadas, al no haberse investigado en detalle sus mecanismos. Los resultados del estudio indican la necesidad de entender mejor la regulación genética de los procesos de biotransformación, para que la información genética pueda incorporarse de manera efectiva en las investigaciones futuras de biotransformación potencial en acuíferos.
Hernández-Hernández, Magda Elena; Morales-Romero, Jaime; Sampieri, Clara Luz; Luna Lozano, Diego Jesús; Valencia Lezama, Isidra Del Carmen; Muñoz Contreras, Mónica Janett; Rodríguez Hernández, Arturo
2017-09-01
Hernández-Hernández, Magda Elena, Jaime Morales-Romero, Clara Luz Sampieri, Diego Jesús Luna Lozano, Isidra del Carmen Valencia Lezama, Mónica Janett Muñoz Contreras, and Arturo Rodríguez Hernández. Association of urinary activity of MMP-2 with microalbuminuria in an isolated sample of subjects living in high altitude rural locations in México. High Alt Med Biol. 18:209-218, 2017.-Matrix metalloproteinases (MMP) are implicated in remodeling of the renal extracellular matrix. In a cross-sectional study we evaluated renal impairment in general population of high-altitude rural locations in México. Multivariable analysis was performed to identify the association between MMP-2 and MMP-9 and microalbuminuria. Twenty-eight (20.9%) subjects with renal impairment (WRI) and 106 (79.1%) without renal impairment were included. No differences were found relating to sex, location, marital status, current habits, weight, height, body mass index, waist size in males, creatinine in males, and uric acid. In contrast, differences were found among age, level of education, waist size in general and in females, creatinine in general and in females, urinary albumin, urea, glucose, total cholesterol, and triglycerides. Proportions of hypertension, type 2 diabetes mellitus, central abdominal obesity, hypertriglyceridemia, and hypercholesterolemia were greater in the group WRI. Presence of urinary MMP-2 or of both urinary gelatinases and arbitrary unit (AU) values ≥P 90 were associated with microalbuminuria. We conclude that AU values ≥P 90 of urinary MMP-2 (OR = 20.1, p = 0.002) is associated with microalbuminuria.
Assessment of unconventional tight-gas resources of the Magallanes Basin Province, Chile, 2015
Schenk, Christopher J.; Charpentier, Ronald R.; Pitman, Janet K.; Tennyson, Marilyn E.; Brownfield, Michael E.; Gaswirth, Stephanie B.; Le, Phuong A.; Leathers-Miller, Heidi M.; Marra, Kristen R.
2016-01-20
Using a geology-based assessment methodology, the U.S. Geological Survey assessed a technically recoverable mean resource of 8.3 trillion cubic feet of unconventional tight gas in the Zona Glauconitica of the Magallanes Basin Province, Chile.
Egea, Teresa; Signorini, Maria Adele; Ongaro, Luca; Rivera, Diego; Obón de Castro, Concepción; Bruschi, Piero
2016-06-22
Traditional alcoholic beverages (TABs) have only received marginal attention from researchers and ethnobotanists so far, especially in Italy. This work is focused on plant-based TABs in the Alta Valle del Reno, a mountainous area on the border between Tuscany and Emilia-Romagna regions. The aims of our study were to document local knowledge about TABs and to analyze and discuss the distribution of related knowledge within the investigated communities. Field data were collected through semi-structured interviews. The relative importance of each plant species used to prepare TABs was assessed by calculating a general Use Value Index (UV general), a current UV (UV current) and a past UV (UV past). We also assessed personal experience of use by calculating effective and potential UV (UV effective, UV potential). A multivariate analysis was performed to compare ingredients in recipes recorded in the Alta Valle del Reno with those reported for neighboring areas. Forty-six plant species, belonging to 20 families, were recorded. Rosaceae was the most significant family (98 citations, 19 species), followed by Rutaceae (15, 3) and Lamiaceae (12, 4). The most important species was Prunus cerasus L. (UV general = 0.44), followed by Juglans regia L. (0.38), Rubus idaeus L. (0.27) and Prunus spinosa L. (0.22). Species with the highest UV current were Juglans regia (0.254), Prunus cerasus (0.238) and Citrus limon L. (0.159). The highest UV effective values were obtained by Prunus cerasus (0.413), Juglans regia (0.254), Rubus idaeus (0.222) and Citrus limon (0.206). We also discuss the results of the multivariate analysis. TABs proved to occupy an important place in the traditional culture and social life of the studied communities. Moreover, data highlight the local specificity and richness of this kind of tradition in the Alta Valle del Reno, compared to other Italian areas. Some plant ingredients used for TABs have potential nutraceutical and even therapeutic properties that are well known by local people. These properties could constitute an additional economic value for TABs' commercialization, which in turn could promote the local rural economy.
Molecular Mechanisms of Stem/Progenitor Cell Maintenance in the Adrenal Cortex
Lerario, Antonio Marcondes; Finco, Isabella; LaPensee, Christopher; Hammer, Gary Douglas
2017-01-01
The adrenal cortex is characterized by three histologically and functionally distinct zones: the outermost zona glomerulosa (zG), the intermediate zona fasciculata, and the innermost zona reticularis. Important aspects of the physiology and maintenance of the adrenocortical stem/progenitor cells have emerged in the last few years. Studies have shown that the adrenocortical cells descend from a pool of progenitors that are localized in the subcapsular region of the zG. These cells continually undergo a process of centripetal displacement and differentiation, which is orchestrated by several paracrine and endocrine cues, including the pituitary-derived adrenocorticotrophic hormone, and angiotensin II. However, while several roles of the endocrine axes on adrenocortical function are well established, the mechanisms coordinating the maintenance of an undifferentiated progenitor cell pool with self-renewal capacity are poorly understood. Local factors, such as the composition of the extracellular matrix (ECM) with embedded signaling molecules, and the activity of major paracrine effectors, including ligands of the sonic hedgehog and Wnt signaling pathways, are thought to play a major role. Particularly, the composition of the ECM, which exhibits substantial differences within each of the three histologically distinct concentric zones, has been shown to influence the differentiation status of adrenocortical cells. New data from other organ systems and different experimental paradigms strongly support the conclusion that the interactions of ECM components with cell-surface receptors and secreted factors are key determinants of cell fate. In this review, we summarize established and emerging data on the paracrine and autocrine regulatory loops that regulate the biology of the progenitor cell niche and propose a role for bioengineered ECM models in further elucidating this biology in the adrenal. PMID:28386245
LGR5 Activates Noncanonical Wnt Signaling and Inhibits Aldosterone Production in the Human Adrenal.
Shaikh, Lalarukh Haris; Zhou, Junhua; Teo, Ada E D; Garg, Sumedha; Neogi, Sudeshna Guha; Figg, Nichola; Yeo, Giles S; Yu, Haixiang; Maguire, Janet J; Zhao, Wanfeng; Bennett, Martin R; Azizan, Elena A B; Davenport, Anthony P; McKenzie, Grahame; Brown, Morris J
2015-06-01
Aldosterone synthesis and cellularity in the human adrenal zona glomerulosa (ZG) is sparse and patchy, presumably due to salt excess. The frequency of somatic mutations causing aldosterone-producing adenomas (APAs) may be a consequence of protection from cell loss by constitutive aldosterone production. The objective of the study was to delineate a process in human ZG, which may regulate both aldosterone production and cell turnover. This study included a comparison of 20 pairs of ZG and zona fasciculata transcriptomes from adrenals adjacent to an APA (n = 13) or a pheochromocytoma (n = 7). Interventions included an overexpression of the top ZG gene (LGR5) or stimulation by its ligand (R-spondin-3). A transcriptome profile of ZG and zona fasciculata and aldosterone production, cell kinetic measurements, and Wnt signaling activity of LGR5 transfected or R-spondin-3-stimulated cells were measured. LGR5 was the top gene up-regulated in ZG (25-fold). The gene for its cognate ligand R-spondin-3, RSPO3, was 5-fold up-regulated. In total, 18 genes associated with the Wnt pathway were greater than 2-fold up-regulated. ZG selectivity of LGR5, and its absence in most APAs, were confirmed by quantitative PCR and immunohistochemistry. Both R-spondin-3 stimulation and LGR5 transfection of human adrenal cells suppressed aldosterone production. There was reduced proliferation and increased apoptosis of transfected cells, and the noncanonical activator protein-1/Jun pathway was stimulated more than the canonical Wnt pathway (3-fold vs 1.3-fold). ZG of adrenal sections stained positive for apoptosis markers. LGR5 is the most selectively expressed gene in human ZG and reduces aldosterone production and cell number. Such conditions may favor cells whose somatic mutation reverses aldosterone inhibition and cell loss.
Resveratrol Improves the Mitochondrial Function and Fertilization Outcome of Bovine Oocytes
TAKEO, Shun; SATO, Daichi; KIMURA, Koji; MONJI, Yasunori; KUWAYAMA, Takehito; KAWAHARA-MIKI, Ryoka; IWATA, Hisataka
2013-01-01
The aim of the present study was to address the effect of resveratrol-mediated upregulation of sirtuin 1 (SIRT1) during oocyte maturation on mitochondrial function, the developmental ability of oocytes and on mechanisms responsible for blockage of polyspermic fertilization. Oocytes collected from slaughterhouse-derived ovaries were cultured in TCM-199 medium supplemented with 10% FCS and 0 or 20 µM resveratrol (Res). We examined the effect of Res on SIRT1 expression in in vitro-matured oocytes (Exp 1); fertilization and developmental ability (Exp 2); mitochondrial DNA copy number (Mt number), ATP content and mitochondrial membrane potential in matured oocytes (Exp 3); and the time required for proteinase to dissolve the zona pellucida following in vitro fertilization (as a marker of zona pellucida hardening), as well as on the distribution of cortical granules before and after fertilization (Exp 4). In Exp 1, the 20 µM Res treatment upregulated protein expression of SIRT1 in oocytes. In Exp 2, Res treatment improved the ratio of normal fertilization and the total cell number of blastocysts. In Exp 3, Res treatment significantly increased the ATP content in matured oocytes. Additionally, Res increased the overall Mt number and mitochondrial membrane potential, but the effect was donor-dependent. In Exp 4, Res-induced zona hardening improved the distribution and exocytosis of cortical granules after in vitro fertilization. In conclusion, Res improved the quality of oocytes by improving mitochondrial quantity and quality. In addition, Res added to the maturation medium enhanced SIRT1 protein expression in oocytes and improved fertilization via reinforcement of the mechanisms responsible for blockage of polyspermic fertilization. PMID:24390595
Sumigama, Shiho; Mansell, Steven; Miller, Melissa; Lishko, Polina V.; Cherr, Gary N.; Meyers, Stuart A.; Tollner, Theodore
2015-01-01
During transit through the female reproductive tract, mammalian spermatozoa are exposed to increasing concentrations of progesterone (P4) released by the cumulus oophorus. P4 triggers massive calcium influx into human sperm through activation of the sperm-specific calcium channel CatSper. These properties of human spermatozoa are thought to be unique since CatSper is not progesterone sensitive in rodent sperm. Here, by performing patch clamp recording from spermatozoa from rhesus macaque for the first time, we report that they express P4-sensitive CatSper channel identically to human sperm and react to P4 by inducing responsiveness to zona pellucida, unlike human sperm, which respond directly to P4. We have also determined the physiologic levels of P4 capable of inducing capacitation-associated changes in macaque sperm. Progesterone (1 μM) induced up to a 3-fold increase in the percentage of sperm undergoing the zona pellucida-induced acrosome reaction with the lowest threshold as low as 10 nM of P4. Submicromolar levels of P4 induced a dose-dependent increase in curvilinear velocity and lateral head displacement, while sperm protein tyrosine phosphorylation was not altered. Macaque spermatozoa exposed to 10 μM of P4 developed fully hyperactivated motility. Similar to human sperm, on approaching cumulus mass and binding to zona pellucida, macaque spermatozoa display hyperactivation and undergo an acrosome reaction that coincides with the rise in the sperm intracellular calcium. Taken together, these data indicate that P4 accelerates the completion of capacitation and provides evidence of spermatozoa “priming” as they move into a gradient of progesterone in search for the oocyte. PMID:26490839
Aldosterone-stimulating somatic gene mutations are common in normal adrenal glands
Nishimoto, Koshiro; Tomlins, Scott A.; Kuick, Rork; Cani, Andi K.; Giordano, Thomas J.; Hovelson, Daniel H.; Liu, Chia-Jen; Sanjanwala, Aalok R.; Edwards, Michael A.; Gomez-Sanchez, Celso E.; Nanba, Kazutaka; Rainey, William E.
2015-01-01
Primary aldosteronism (PA) represents the most common cause of secondary hypertension, but little is known regarding its adrenal cellular origins. Recently, aldosterone-producing cell clusters (APCCs) with high expression of aldosterone synthase (CYP11B2) were found in both normal and PA adrenal tissue. PA-causing aldosterone-producing adenomas (APAs) harbor mutations in genes encoding ion channels/pumps that alter intracellular calcium homeostasis and cause renin-independent aldosterone production through increased CYP11B2 expression. Herein, we hypothesized that APCCs have APA-related aldosterone-stimulating somatic gene mutations. APCCs were studied in 42 normal adrenals from kidney donors. To clarify APCC molecular characteristics, we used microarrays to compare the APCC transcriptome with conventional adrenocortical zones [zona glomerulosa (ZG), zona fasciculata, and zona reticularis]. The APCC transcriptome was most similar to ZG but with an enhanced capacity to produce aldosterone. To determine if APCCs harbored APA-related mutations, we performed targeted next generation sequencing of DNA from 23 APCCs and adjacent normal adrenal tissue isolated from both formalin-fixed, paraffin-embedded, and frozen tissues. Known aldosterone driver mutations were identified in 8 of 23 (35%) APCCs, including mutations in calcium channel, voltage-dependent, L-type, α1D-subunit (CACNA1D; 6 of 23 APCCs) and ATPase, Na+/K+ transporting, α1-polypeptide (ATP1A1; 2 of 23 APCCs), which were not observed in the adjacent normal adrenal tissue. Overall, we show three major findings: (i) APCCs are common in normal adrenals, (ii) APCCs harbor somatic mutations known to cause excess aldosterone production, and (iii) the mutation spectrum of aldosterone-driving mutations is different in APCCs from that seen in APA. These results provide molecular support for APCC as a precursor of PA. PMID:26240369
Diestel, Uschi; Resch, Marcus; Meinhardt, Kathrin; Weiler, Sigrid; Hellmann, Tina V.; Mueller, Thomas D.; Nickel, Joachim; Eichler, Jutta; Muller, Yves A.
2013-01-01
The zona pellucida (ZP) domain is present in extracellular proteins such as the zona pellucida proteins and tectorins and participates in the formation of polymeric protein networks. However, the ZP domain also occurs in the cytokine signaling co-receptor transforming growth factor β (TGF-β) receptor type 3 (TGFR-3, also known as betaglycan) where it contributes to cytokine ligand recognition. Currently it is unclear how the ZP domain architecture enables this dual functionality. Here, we identify a novel major TGF-β-binding site in the FG loop of the C-terminal subdomain of the murine TGFR-3 ZP domain (ZP-C) using protein crystallography, limited proteolysis experiments, surface plasmon resonance measurements and synthetic peptides. In the murine 2.7 Å crystal structure that we are presenting here, the FG-loop is disordered, however, well-ordered in a recently reported homologous rat ZP-C structure. Surprisingly, the adjacent external hydrophobic patch (EHP) segment is registered differently in the rat and murine structures suggesting that this segment only loosely associates with the remaining ZP-C fold. Such a flexible and temporarily-modulated association of the EHP segment with the ZP domain has been proposed to control the polymerization of ZP domain-containing proteins. Our findings suggest that this flexibility also extends to the ZP domain of TGFR-3 and might facilitate co-receptor ligand interaction and presentation via the adjacent FG-loop. This hints that a similar C-terminal region of the ZP domain architecture possibly regulates both the polymerization of extracellular matrix proteins and cytokine ligand recognition of TGFR-3. PMID:23826237
Mendonça, Pedro O R de; Lotfi, Claudimara F P
2011-04-10
Modified synthetic N-POMC(1-28) without disulfide bridges has been shown to act as an adrenal mitogen. Cyclins and their inhibitors are the major cell cycle controls, but in the adrenal cortex the effect of ACTH and N-POMC on the expression of these proteins remains unclear. In this work, we evaluate the effect of different synthetic N-POMC peptides on the S-phase of the cell cycle. In addition, we examine the cyclin E expression in rat adrenal cortex. Rats treated with dexamethasone were injected with ACTH and/or synthetic modified N-POMC and/or synthetic N-POMC with disulfide bridges. DNA synthesis was determined by BrdU incorporation and protein expression was analyzed by immunoblotting and immunohistochemistry. The results showed that similarly to modified N-POMC without disulfide bridges, administration of synthetic N-POMC with disulfide bridges and the combination of ACTH and N-POMC promoted an increase of BrdU-positive nuclei in adrenal cortex. However, the proliferative effect of N-POMC was comparable to that of ACTH only in the zona glomerulosa. An increase in cyclin E expression was observed 6 h after N-POMC treatment in the outer fraction of the adrenal cortex, in agreement with immunohistochemical findings in the zona glomerulosa. In summary, the effect of synthetic N-POMC with disulfide bridges was similar to modified synthetic N-POMC, increasing proliferation in the adrenal cortex, confirming previous evidence that disulfide bridges are not essential to the N-POMC mitogenic effect. Moreover, cyclin E appears to be involved in the N-POMC- and ACTH-stimulated proliferation in the zona glomerulosa of the adrenal cortex. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Cheng, Behling; Al-Shammari, Fatema H; Ghader, Isra'a A; Sequeira, Fatima; Thakkar, Jitendra; Mathew, Thazhumpal C
2017-07-01
Adrenal gland reportedly expresses many nuclear receptors that are known to heterodimerize with retinoid-X-receptor (RXR) for functions, but the information regarding the glandular RXR is not adequate. Studies of rat adrenal homogenate by Western blotting revealed three RXR proteins: RXRα (55kDa), RXRβ (47kDa) and RXR (56kDa). RXRγ was not detectable. After fractionation, RXRα was almost exclusively localized in the nuclear fraction. In comparison, substantial portions of RXRβ and RXR were found in both nuclear and post-nuclear particle fractions, suggesting genomic and non-genomic functions. Cells immunostained for RXRα were primarily localized in zona fasciculata (ZF) and medulla, although some stained cells were found in zona glomerulosa (ZG) and zona reticularis (ZR). In contrast, cells immunostained for RXRβ were concentrated principally in ZG, although some stained cells were seen in ZR, ZF, and medulla (in descending order, qualitatively). Analysis of adrenal lipid extracts by LC/MS did not detect 9-cis-retinoic acid (a potent RXR-ligand) but identified all-trans retinoic acid. Since C20 and C22 polyunsaturated fatty acids (PUFAs) can also activate RXR, subcellular availabilities of unesterified fatty acids were investigated by GC/MS. As results, arachidonic acid (C20:4), adrenic acid (C22:4), docosapentaenoic acid (C22:5), and cervonic acid (C22:6) were detected in the lipids extracted from each subcellular fraction. Thus, the RXR-agonizing PUFAs are available in all the main subcellular compartments considerably. The present findings not only shed light on the adrenal network of RXRs but also provide baseline information for further investigations of RXR heterodimers in the regulation of adrenal steroidogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.
Moro, L N; Jarazo, J; Buemo, C; Hiriart, M I; Sestelo, A; Salamone, D F
2015-10-01
The aim of this study was to evaluate three different cloning strategies in the domestic cat (Felis silvestris) and to use the most efficient to generate wild felid embryos by interspecific cloning (iSCNT) using Bengal (a hybrid formed by the cross of Felis silvestris and Prionailurus bengalensis) and tiger (Panthera tigris) donor cells. In experiment 1, zona-free (ZP-free) cloning resulted in higher fusion and expanded blastocyst rates with respect to zona included cloning techniques that involved fusion or injection of the donor cell. In experiment 2, ZP-free iSCNT and embryo aggregation (2X) were assessed. Division velocity and blastocyst rates were increased by embryo aggregation in the three species. Despite fewer tiger embryos than Bengal and cat embryos reached the blastocyst stage, Tiger 2X group increased the percentage of blastocysts with respect to Tiger 1X group (3.2% vs 12.1%, respectively). Moreover, blastocyst cell number was almost duplicated in aggregated embryos with respect to non-aggregated ones within Bengal and tiger groups (278.3 ± 61.9 vs 516.8 ± 103.6 for Bengal 1X and Bengal 2X groups, respectively; 41 vs 220 ± 60 for Tiger 1X and Tiger 2X groups, respectively). OCT4 analysis also revealed that tiger blastocysts had higher proportion of OCT4-positive cells with respect to Bengal blastocysts and cat intracytoplasmic sperm injection blastocysts. In conclusion, ZP-free cloning has improved the quality of cat embryos with respect to the other cloning techniques evaluated and was successfully applied in iSCNT complemented with embryo aggregation. © 2015 Blackwell Verlag GmbH.
Jia, Zhenzhen; Feng, Zeyang; Wang, Lining; Li, Hao; Wang, Hongyu; Xu, Dingqi; Zhao, Xin; Feng, Daofu; Feng, Xizeng
2018-05-23
Reproductive dysfunction associated with obesity is increasing among women of reproductive age, including infertility and increasing risk of miscarriage. In females, reproductive disorders are linked to declining quality of oocytes. Using a model of diet-induced obesity, we have investigated the possible effects of obesity on oocyte quality, including metabolism, lipid accumulation, ROS levels, meiosis and changes in spindle structure in Metaphase II. Our study showed that obesity induced by a high fat diet can impair oocyte meiosis, destroy spindle assembly, and promote oxidative stress and abnormal mitochondrial distribution. With the addition of resveratrol, the negative impact of diet-induced obesity on the quality of oocytes was alleviated to some extent. In addition, we found that obesity causes mouse oocytes to soften, and resveratrol can restore the zona pellucida of oocytes to the same state as the control group. In conclusion, resveratrol can reverse the adverse effects of obesity on oocytes, which is beneficial for subsequent embryonic development.
Milestones in contraceptive vaccines development and hurdles in their application
Gupta, Satish Kumar; Shrestha, Abhinav; Minhas, Vidisha
2014-01-01
Contraceptive vaccines have been proposed for controlling the growing human population and wildlife population management. Multiple targets such as gonadotropin releasing hormone (GnRH), luteinizing hormone, follicle stimulating hormone, gonadotropin receptors, sperm-specific proteins and zona pellucida glycoproteins have been exploited to develop contraceptive vaccine and their efficacy investigated and shown in various experimental animal models. Vaccines based on GnRH have found application in immuno-castration of male pigs for prevention of boar-taint. Vaccines based on zona pellucida glycoproteins have shown promising results for population management of wild horses and white-tailed deer. Phase II clinical trials in women with β-human chorionic gonadotropin (β-hCG)-based contraceptive vaccine established proof of principle that these can be developed for human application. Block in fertility by β-hCG contraceptive vaccine was reversible. Further research inputs are required to establish the safety of contraceptive vaccines, improve their immunogenicity and to develop novel vaccine delivery platforms for providing long lasting immunity. PMID:24262991
Szabó, D; Somogyi, J; Acs, Z; Mihály, K
1980-01-01
The effect of reduced blood and adrenal cholesterol levels on adrenocortical lipid droplets have been examined by treating adult rats with 4-amino-pyrazolo-(3,4 d) pyrimidine (4-APP), a drug that inhibits hepatic secretion of lipoproteins. Lowering the blood cholesterol level and the cholesterol content of the adrenals was associated with a marked reduction in the lipid droplets and with a simultaneous increase in their electron density in the inner cortical zones. In the zona glomerulosa cells, no perceptible differences were found in the quantity and morphology of lipid droplets. These data suggest that reduced blood and adrenal cholesterol levels do not affect lipids located in the zona glomerulosa and in the inner cortical zones in the same way, probably due to differences in their intracellular lipid dynamism. Noteworthy, that in spite of the marked lipid depletion, the adrenal glands retained their responsiveness to ACTH stimulation.
NASA Astrophysics Data System (ADS)
Senthilkumar, M.; Elango, L.
A three-dimensional mathematical model to simulate regional groundwater flow was used in the lower Palar River basin, in southern India. The study area is characterised by heavy ion of groundwater for agricultural, industrial and drinking water supplies. There are three major pumping stations on the riverbed apart from a number of wells distributed over the area. The model simulates groundwater flow over an area of about 392 km2 with 70 rows, 40 columns, and two layers. The model simulated a transient-state condition for the period 1991-2001. The model was calibrated for steady- and transient-state conditions. There was a reasonable match between the computed and observed heads. The transient model was run until the year 2010 to forecast groundwater flow under various scenarios of overpumping and less recharge. Based on the modelling results, it is shown that the aquifer system is stable at the present rate of pumping, excepting for a few locations along the coast where the groundwater head drops from 0.4 to 1.81 m below sea level during the dry seasons. Further, there was a decline in the groundwater head by 0.9 to 2.4 m below sea level in the eastern part of the area when the aquifer system was subjected to an additional groundwater withdrawal of 2 million gallons per day (MGD) at a major pumping station. Les modèles mathématiques en trois dimensions de l'écoulement souterrain régional sont très utiles pour la gestion des ressources en eau souterraine, car ils permettent une évaluation des composantes des processus hydrologiques et fournissent une description physique de l'écoulement de l'eau dans un aquifère. Une telle modélisation a été entreprise sur une partie du bassin inférieur de la rivière Palar, dans le sud de l'Inde. La zone d'étude est caractérisée par des prélèvements importants d'eau souterraine pour l'agriculture, l'industrie et l'eau potable. Il existe trois grandes stations de pompage sur la rivière en plus d'un certain nombre de puits répartis dans cette région. Le modèle simule l'écoulement souterrain dans une région d'environ 392 km2 avec 70 rangs, 40 colonnes et deux couches. Le modèle a fonctionné en régime transitoire en utilisant une approximation aux différences finies d'une équation différentielle partielle en trois dimensions de l'écoulement souterrain dans cet aquifère pour la période 1991-2001. Le modèle a été calibré pour des conditions de régime permanent et transitoire. Les charges hydrauliques calculées étaient en bon accord avec celles observées. Sur la base des résultats du modèle, il est apparu que le système aquifère est stable pour ce taux de pompage, excepté en quelques sites le long de la côte où l'eau marine a pénétré 50-100 m dans les terres. Le modèle transitoire a tourné jusqu'en 2010 afin de prévoir l'écoulement souterrain dynamique pour différents scénarios de pompage excessif et de recharge réduite. Il se produit un abaissement de la piézométrie de la nappe de 0.6 à 0.8 m dans la partie orientale, alors que l'aquifère est soumis à un prélèvement supplémentaire de 8,000 m3/jour à l'une des stations principales de pompage. Même avec le niveau actuel de pompage, la piézométrie de la nappe descendrait sous le niveau de la mer au cours des saisons sèches. Le modèle prédit le fonctionnement du système aquifère sous différentes conditions de stress hydrologique. Los modelos tridimensionales de flujo de aguas subterráneas son útiles para gestionar los recursos hídricos subterráneos, ya que proporcionan una aproximación a los diversos procesos hidrológicos y una descripción cuantitativa del flujo de agua en el acuífero. Se ha desarrollado un estudio de modelación de este tipo en una parte de la cuenca baja del río Palar, en el Sur de la India. Esta zona se caracteriza por las intensas extracciones de aguas subterráneas para usos agrícolas, industriales y domésticos. Hay tres estaciones de bombeo principales en el río, además de numerosos pozos distribuidos por la zona. El modelo simula el flujo de las aguas subterráneas en una superficie de 392 km2 por medio de 70 filas, 40 columnas y 2 capas. El modelo ha sido empleado en condiciones transitorias, por medio de la aproximación en diferencias finitas de las ecuaciones diferenciales parciales en tres dimensiones del flujo en el acuífero durante el período 1991-2001. Se ha calibrado el modelo en condiciones permanentes y transitorias. El ajuste entre los niveles calculados y medidos es razonable. A partir de los resultados de la modelación, se ha obtenido que el sistema acuífero es estable con la tasa de bombeo utilizada, exceptuando unos pocos emplazamientos a lo largo de la costa, donde se ha dado lugar a fenómenos de intrusión marina en una distancia de 50-100 m. El modelo transitorio ha sido ejecutado hasta el año 2010 para predecir el flujo dinámico bajo diversos escenarios de sobreexplotación y de reducción de la recarga. Se produce una disminución en los niveles piezométricos de 0.6 a 0.8 m en la zona oriental, donde el sistema acuífero está sometido a una extracción adicional de 2 millones de galones por día en la estación principal de bombeo. Incluso con las extracciones actuales, los niveles piezométricos se sitúan bajo el nivel del mar durante las épocas secas. El modelo predice el comportamiento de este sistema acuífero bajo varias condiciones de presión hidrológica.
Deep data science to prevent and treat growth faltering in Maya children.
Varela-Silva, M I; Bogin, B; Sobral, J A G; Dickinson, F; Monserrat-Revillo, S
2016-06-01
The Maya people are descended from the indigenous inhabitants of southern Mexico, Guatemala and adjacent regions of Central America. In Guatemala, 50% of infants and children are stunted (very low height-for-age), and some rural Maya regions have >70% children stunted. A large, longitudinal, intergenerational database was created to (1) provide deep data to prevent and treat somatic growth faltering and impaired neurocognitive development, (2) detect key dependencies and predictive relations between highly complex, time-varying, and interacting biological and cultural variables and (3) identify targeted multifactorial intervention strategies for field testing and validation. Contributions to this database included data from the Universidad del Valle de Guatemala Longitudinal Study of Child and Adolescent Development, child growth and intergenerational studies among the Maya in Mexico and studies about Maya migrants in the United States.
Sequías Hidrológicas en la República Argentina y su relación con Variables Macroclimáticas
NASA Astrophysics Data System (ADS)
Díaz, Erica Betiana
2016-07-01
Una adecuada planificación y gestión requiere un conocimiento de la distribución temporal y espacial de los recursos hídricos. Una amenaza que afecta al desarrollo y aprovechamiento de los recursos hídricos, y para las cuales la ingeniería debe dar soluciones, son las situaciones de extremos hidrológicos como inundaciones o sequías. Siendo estas últimas un fenómeno hidrológico extremo de gran complejidad del cual aún se conoce poco. Con el objetivo de identificar y caracterizar temporal y espacialmente las sequías hidrológicas en Argentina, esta tesis abordó en primera instancia, la identificación y caracterización de sequías desde el punto de vista hidrológico, abarcando el mayor período de tiempo y espacio, en función de los datos de caudales disponibles. Con el fin de predecir eventos plurianuales de sequías hidrológicas en el mediano y largo plazo se generaron, a través del análisis espectral y armónico de las series históricas de caudales observados, series sintéticas que reproducen las componentes periódicas plurianuales más significativas de las series observadas. Además, para lograr un avance en el conocimiento de los fenómenos climáticos que conducen a las sequías hidrológicas, se identificaron las variables macroclimáticas que tienen una mayor correlación con los caudales escurridos en las distintas cuencas. Esta tesis comprende el estudio de 14 cuencas hidrográficas argentinas, pertenecientes a los ríos Colorado, Mendoza, San Juan, Atuel, Ctalamochita, Anizacate, Xanaes, Suquía, Dulce, Juramento, Salado, Paraná, Bermejo y Pilcomayo. Los resultados a los que se abordaron en esta tesis son de relevancia para la gestión de los recursos hídricos ya que usos tales como el abastecimiento humano, el riego y la producción energética, entre otros, pueden ser seriamente afectados por la ocurrencia de manera simultánea de sequías severas en cuencas que aportan a una región y zonas vecinas.
Evolución de estrellas enanas blancas de Helio de masa baja e intermedia
NASA Astrophysics Data System (ADS)
Althaus, L. G.; Benvenuto, O. G.
Numerosas observaciones realizadas particularmente en los últimos dos años parecen confirmar que las enanas blancas (EB) de helio de masa baja e intermedia son el resultado de la evolución de sistemas binarios cercanos. Con el objeto de realizar una adecuada interpretación de estos objetos son necesarios modelos de EBs de helio lo más detallado posibles. En este estudio presentamos cálculos detallados de la evolución de EBs de helio con masas entre M=0.1Msolar y M=0.5Msolar a intervalos de 0.05Msolar . Para ello, hemos tenido en cuenta los efectos de temperatura finita mediante un código de evolución estelar lo más actualizado posible. En particular, el transporte de energía es descripto en el marco del nuevo modelo para la convección turbulenta desarrollado por Canuto - Mazzitelli. Además hemos considerado la nueva ecuación de estado para plasmas de helio de Saumon et al. y nuevas opacidades radiativas OPAL. Las pérdidas por neutrinos fueron asimismo tenidas en cuenta. Excepto para las EBs más masivas, nuestros modelos iniciales están ubicados en las cercanías de la correspondiente línea de Hayashi para configuraciones de helio. Nuestros resultados muestran que existe una región prohibida en el diagrama observacional HR donde ninguna EB de helio puede encontrarse. Dicha región es para log{(L/Lsolar )}>= -0.25 and log{Teff} >= 4.45. Hemos encontrado también que los tracks evolutivos en el diagrama HR en el dominio de alta luminosidad (pre - EB) son fuertemente afectados por la eficiencia convectiva y que las pérdidas por neutrinos son importantes en los modelos más masivos. Finalmente hemos analizado la estructura de la zona convectiva externa encontrando que la teoría de Canuto - Mazzitelli conduce a un perfil convectivo muy diferente del dado por cualquier versión de la popular teoría de la mixing length. Si bién este comportamiento es decisivo en el contexto de las inestabilides pulsacionales, los radios y gravedades superficiales de los modelos no son afectados al incluir la nueva teoría de convección.
Code of Federal Regulations, 2010 CFR
2010-01-01
..., and sterilization. (1) All equipment that comes in contact with embryos or with media used for their... found to be intact and free from any adherent material. (5) After washing and examination of the zona... be moved to a U.S. Department of Agriculture-operated animal import center in either New York, Hawaii...
Code of Federal Regulations, 2011 CFR
2011-01-01
..., and sterilization. (1) All equipment that comes in contact with embryos or with media used for their... found to be intact and free from any adherent material. (5) After washing and examination of the zona... be moved to a U.S. Department of Agriculture-operated animal import center in either New York, Hawaii...
NASA Astrophysics Data System (ADS)
Varni, Marcelo R.; Usunoff, Eduardo J.
A three-dimensional modular model (MODFLOW) was used to simulate groundwater flow in the Azul River basin, Buenos Aires Province, Argentina, in order to assess the correctness of the conceptual model of the hydrogeological system. Simulated heads satisfactorily match observed heads in the regional water-table aquifer. Model results indicate that: (1) groundwater recharge is not uniform throughout the region but is best represented by three recharge rates, decreasing downgradient, similar to the distribution of soils and geomorphological characteristics; and (2) evapotranspiration rates are larger than previous estimates, which were made by using the Thornthwaite-Mather method. Evapotranspiration rates estimated by MODFLOW agree with results of independent studies of the region. Model results closely match historical surface-flow records, thereby suggesting that the model description of the aquifer-river relationship is correct. Résumé Un modèle modulaire tridimensionnel (MODFLOW) a été utilisé pour simuler les écoulements souterrains dans le bassin de la rivière Azul (Province de Buenos Aires, Argentine), dans le but d'évaluer la justesse du modèle conceptuel du système hydrogéologique. La piézométrie simulée s'ajuste de façon satisfaisante à celle observée pour l'ensemble de la nappe. Les résultats du modèle indiquent que: (1) la recharge de la nappe n'est pas uniforme sur toute la région, mais qu'elle est mieux approchée par trois valeurs différentes, décroissant vers l'aval-gradient, en suivant la même distribution que les sols et les caractéristiques géomorphologiques et (2) l'évapotranspiration est nettement plus importante que prévu initialement à partir de la méthode de Thornthwaite-Mather. Les valeurs d'évapotranspiration fournies par MODFLOW concordent bien avec les résultats d'autres études portant sur la région. Les résultats du modèle reproduisent convenablement les chroniques de débit des écoulements de surface, suggérant ainsi que la description par le modèle des relations rivière-nappe est correcte. Resumen Se ha utilizado el modelo MODFLOW, del Servicio Geológico de los Estados Unidos, para simular el flujo de agua subterránea en la cuenca del arroyo del Azul, Provincia de Buenos Aires, Argentina, con el objeto de evaluar el modelo hidrogeológico conceptual. Los niveles hidráulicos simulados ajustan satisfactoriamente con los niveles observados. Los resultados de la simulación indican que: (1) la recarga no es uniforme, sino que puede caracterizarse con tres zonas en las que sus valores decrecen en la medida en que decrece la pendiente, que guarda similitud con la distribución de suelos y características geomorfológicas y (2) la evapotranspiración sería mayor que la estimada en estudios previos, en los que se utilizó el método de Thornthwaite-Mather. La evapotranspiración estimada mediante la presente simulación concuerda con resultados de varios estudios independientes en la región. Respecto de la relación acuífero-río, existe un muy buen ajuste entre los aportes del acuífero al río simulados y los valores históricos de caudal base.
NASA Astrophysics Data System (ADS)
Trogello, Anderson Giovani; Danhoni Neves, Marcos Cesar; de Carvalho Rutz da Silva, Sani
2013-12-01
Many misconceptions are recognized among the various groups of students, especially in the elementary school. Among them, the apparent motion of the Sun, in spite of its daily occurrence, is subject to varied interpretations. Thus, the observation and recording of the motion of the stars in the celestial vault is a necessary task for astronomy education. The work presented here proposes the presentation of the results of observations of the apparent movement of the sun by marking the shadow of a vertical gnomon by the students in a class of sixth graders of elementary rural school of Paraná. The project itself was conducted in four stages, on dates near the March equinox, the June solstice, the September equinox and the December solstice. In addition, lectures were developed in the classroom. Such methods sought to build concepts around the apparent movement of the Sun and the alternation of the seasons. Given the results of the activities, an evaluation was applied and the data demonstrated a desired student learning such as: the recognition of the cardinal points, the description of the apparent solar motion and the occurrence of the seasons and their alternation from astronomical observations at naked eye. Muchos conceptos aternativos son conocidos entre los distintos grupos de alumnos, sobre todo en la educación básica. Entre ellos, el movimiento aparente del Sol, por más cotidiano que sea, se presta a interpretaciones variadas. Por lo tanto, observar y registrar el movimiento de las estrellas en la bóveda celeste se torna una tarea necesaria para la educación en astronomía. El trabajo que aquí se presenta propone la presentación de los resultados de la observación del movimiento aparente del sol a través de la marcación de la sombra del gnomon vertical a cargo de los estudiantes en una división de sexto grado de de la escuela primaria rural de Paraná. El proyecto en sí se llevó a cabo en cuatro etapas, en fechas cercanas al equinoccio de marzo, al solsticio de junio, al equinoccio de septiembre y al solsticio de diciembre. Además, se dictaron clases teóricas en la sala de aula. Estos métodos buscaron construir conceptos en torno al movimiento aparente del Sol y la sucesión de las estaciones. Teniendo en cuenta los resultados de las actividades se aplicó una evaluación cuyos datos demuestran la existencia de un aprendizaje deseado por los estudiantes en cuanto a: el reconocimiento de los puntos cardinales, la descripción del movimiento solar aparente y la aparición de las estaciones y su alternancia a partir de observaciones astronómicas visuales sin instrumentos. Muitas concepções alternativas são reconhecidas entre os diversos grupos de estudantes, em especial nos da educação básica. Dentre elas, o movimento aparente do Sol, por mais quotidiano que seja, proporciona variadas interpretações. Deste modo, observar e registrar o movimento dos astros na abóboda celeste é uma tarefa necessária ao ensino de Astronomia. O trabalho que ora se apresenta propõe a apresentação dos resultados da observação do movimento aparente do Sol por intermédio da marcação da sombra de um gnômon vertical por alunos de uma turma do sexto ano do ensino fundamental de uma escola do campo do Paraná. O projeto em si ocorreu em quatro etapas, em datas próximas do equinócio de março, do solstício de junho, do equinócio de setembro e do solstício de dezembro. Além disso, foram desenvolvidas aulas teóricas em sala de aula. Tais métodos buscaram construir conceitos em torno da movimentação aparente do Sol e da alternância das estações do ano. Diante dos resultados provenientes das atividades desenvolvidas foi aplicada uma avaliação e os dados demonstraram um aprendizado desejado dos alunos quanto: ao reconhecimento dos pontos cardeais; à descrição do movimento solar aparente e a ocorrência das estações do ano e sua alternância a partir de observações astronômicas a olho nu.
Ciofi-Silva, Caroline Lopes; Hansen, Lisbeth Lima; Almeida, Alda Graciele Claudio Dos Santos; Kawagoe, Julia Yaeko; Padoveze, Maria Clara; Graziano, Kazuko Uchikawa
2016-09-01
to analyze the scientific evidence on aerosols generated during cleaning activities of health products in the Central Service Department (CSD) and the impact of the negative pressure of the ambient air in the cleaning area to control the dispersion of aerosols to adjacent areas. for this literature systematic review the following searches were done: search guidelines, manuals or national and international technical standards given by experts; search in the portal and databases PubMed, Scopus, CINAHL and Web of Science; and a manual search of scientific articles. the five technical documents reviewed recommend that the CSD cleaning area should have a negative differential ambient air pressure, but scientific articles on the impact of this intervention were not found. The four articles included talked about aerosols formed after the use of a ultrasonic cleaner (an increased in the contamination especially during use) and pressurized water jet (formation of smaller aerosols 5μm). In a study, the aerosols formed from contaminated the hot tap water with Legionella pneumophila were evaluated. there is evidence of aerosol formation during cleanup activities in CSD. Studies on occupational diseases of respiratory origin of workers who work in CSD should be performed. analisar as evidências científicas sobre aerossóis gerados durante atividades de limpeza dos produtos para saúde no Centro de Material e Esterilização (CME) e o impacto da pressão negativa do ar ambiente na área de limpeza para controle da dispersão de aerossóis para áreas adjacentes. para essa revisão sistemática de literatura foram realizadas: busca de diretrizes, manuais ou normas técnicas nacionais e internacionais indicadas por especialistas; busca no portal e bases de dados PUBMED, SCOPUS, Cinahl e Web of Science; e busca manual de artigos científicos. Os cinco documentos técnicos analisados preconizam que na área de limpeza do CME haja diferencial negativo de pressão do ar ambiente, porém não foram encontrados artigos científicos sobre o impacto dessa intervenção. Os quatro artigos incluídos trataram dos aerossóis formados após uso de lavadora ultrassônica (aumento da contaminação principalmente durante o uso) e do jato de água pressurizado (formação de aerossóis menores que 5µm). Em um estudo foram avaliados aerossóis formados a partir de torneira de água quente contaminada com Legionella pneumophila. há evidências sobre formação de aerossóis durante atividades de limpeza em CME. Estudos sobre doenças ocupacionais de origem respiratória dos trabalhadores que atuam em CME devem ser realizados. examinar la evidencia científica sobre los aerosoles generados durante las actividades de limpieza de productos de salud en el Centro de Materiales y Esterilización (CME) y el impacto de la presión negativa del aire ambiente en la zona de limpieza para controlar la dispersión de aerosoles a las zonas adyacentes. para esta revisión sistemática de literatura se llevaron a cabo: búsqueda de directrices, manuales o normas técnicas nacionales e internacionales impartidas por expertos; búsqueda en las bases de datos PUBMED, SCOPUS, Cinahl y Web of Science; y búsqueda manual de artículos científicos. Los cinco documentos técnicos analizados recomiendan que el área de limpieza del CME tenga un diferencial negativo de presión en el aire ambiente, aunque no se han encontrado artículos científicos sobre el impacto de esta intervención. Los cuatro artículos incluidos fueron sobre los aerosoles formados después del uso de la lavadora ultrasónica (aumento de la contaminación, especialmente durante el uso) y chorro de agua a presión (formación de aerosoles menores a 5µm). De esta forma, en un solo estudio se evaluaron los aerosoles formados a partir de un grifo de agua caliente contaminada con Legionella pneumophila. hay evidencia de formación de aerosoles durante las actividades de limpieza en CME. Sin embargo, es necesario realizar estudios sobre las enfermedades profesionales de origen respiratorio de los trabajadores que trabajan en CME.
Geostatistical mapping of leakance in a regional aquitard, Oak Ridges Moraine area, Ontario, Canada
NASA Astrophysics Data System (ADS)
Desbarats, A. J.; Hinton, M. J.; Logan, C. E.; Sharpe, D. R.
2001-01-01
The Newmarket Till forms a regionally extensive aquitard separating two major aquifer systems in the Greater Toronto area, Canada. The till is incised, and sometimes eroded entirely, by a network of sand- and gravel-filled channels forming productive aquifers and, locally, high-conductivity windows between aquifer systems. Leakage through the till may also be substantial in places. This study investigates the spatial variability of aquitard leakance in order to assess the relative importance of recharge processes to the lower aquifers. With a large database derived from water-well records and containing both hard and soft information, the Sequential Indicator Simulation method is used to generate maps of aquitard thickness and window probability. These can be used for targeting channel aquifers and for identifying potential areas of recharge to the lower aquifers. Conductivities are modeled from sparse data assuming that their correlation range is much smaller than the grid spacing. Block-scale leakances are obtained by upscaling nodal values based on simulated conductivity and thickness fields. Under the "aquifer-flow'' assumption, upscaling is performed by arithmetic spatial averaging. Histograms and maps of upscaled leakances show that heterogeneities associated with aquitard windows have the largest effect on regional groundwater flow patterns. Résumé. La moraine glaciaire de Newmarket constitue un imperméable d'extension régionale séparant deux systèmes aquifères dans la région du Grand Toronto (Canada). La moraine est entaillée, et parfois entièrement érodée, par un réseau de chenaux comblés de sables et de graviers formant des aquifères productifs et, localement, des «fenêtres», zones à forte conductivité hydraulique reliant les systèmes aquifères. Une drainance au travers de la moraine peut également être significative par endroits. Cette étude s'intéresse à la variabilité spatiale de la drainance au travers de l'imperméable, dans le but d'évaluer l'importance relative des processus d'alimentation des aquifères inférieurs. À partir d'une vaste base de données constituée par les mesures faites dans les puits et contenant des informations à la fois certaines et incertaines, la méthode de simulation par indicateur séquentiel est utilisée pour créer des cartes d'épaisseur de l'imperméable et de probabilité d'existence des fenêtres. Ces cartes peuvent être utilisées pour mettre en évidence les aquifères de chenaux et pour identifier les zones potentielles de recharge des aquifères inférieurs. Les conductivités hydrauliques sont modélisées à partir de données clairsemées en supposant que leur gamme de corrélation est beaucoup plus faible que le pas de la grille. La drainance à l'échelle des blocs est obtenue par accroissement du niveau d'échelle des valeurs nodales basé sur les champs de conductivité simulée et des épaisseurs. À partir de l'hypothèse d'écoulement dans l'aquifère, l'accroissement d'échelle est réalisé en faisant une moyenne arithmétique spatiale. Des histogrammes et des cartes de drainance avec accroissement d'échelle montrent que les hétérogénéités associées aux fenêtres dans l'imperméable constituent l'effet le plus important dans l'organisation des écoulements souterrains régionaux. Resumen. El Till de Newmarket forma un acuitardo de extensión regional que separa dos sistemas acuíferos principales en la zona de Greater Toronto (Canadá). El till está horadado, y a veces completamente erosionado, por una red de canales rellenos de arena y grava. Estos constituyen acuíferos productivos y, localmente, conexiones de alta permeabilidad entre sistemas acuíferos. El goteo a través del till puede ser fundamental en ciertos lugares. Este estudio investiga la variabilidad espacial del goteo desde el acuitardo con el fin de establecer la importancia relativa de los procesos de recarga hacia los acuíferos inferiores. Se ha utilizado el método de la Simulación Indicadora Secuencial, soportado por una gran base de datos que contiene registros de sondeos e incluye información blanda y dura, para generar mapas de espesor del acuitardo y mapas de probabilidad de discontinuidades laterales en el acuitardo. Estos resultados se pueden emplear para identificar canales y las zonas de recarga potencial a los acuíferos inferiores. Se han modelado las conductividades a partir de datos dispersos, suponiendo que la distancia de correlación es mucho menor que el espaciado de la malla. Se han calculado valores de goteo a escala de bloque por medio del escalado de los valores nodales, basándose en los campos simulados de conductividad y espesor. El escalado se calcula mediante un promedio aritmético espacial, bajo la hipótesis de "flujo en el acuífero". Los histogramas y mapas de goteos escalados muestran que las heterogeneidades asociadas a las discontinuidades en el acuitardo producen el efecto más notable en la distribución regional del flujo de aguas subterráneas.
Using operational data to estimate the reliable yields of water-supply wells
NASA Astrophysics Data System (ADS)
Misstear, Bruce D. R.; Beeson, Sarah
The reliable yield of a water-supply well depends on many different factors, including the properties of the well and the aquifer; the capacities of the pumps, raw-water mains, and treatment works; the interference effects from other wells; and the constraints imposed by ion licences, water quality, and environmental issues. A relatively simple methodology for estimating reliable yields has been developed that takes into account all of these factors. The methodology is based mainly on an analysis of water-level and source-output data, where such data are available. Good operational data are especially important when dealing with wells in shallow, unconfined, fissure-flow aquifers, where actual well performance may vary considerably from that predicted using a more analytical approach. Key issues in the yield-assessment process are the identification of a deepest advisable pumping water level, and the collection of the appropriate well, aquifer, and operational data. Although developed for water-supply operators in the United Kingdom, this approach to estimating the reliable yields of water-supply wells using operational data should be applicable to a wide range of hydrogeological conditions elsewhere. Résumé La productivité d'un puits capté pour l'adduction d'eau potable dépend de différents facteurs, parmi lesquels les propriétés du puits et de l'aquifère, la puissance des pompes, le traitement des eaux brutes, les effets d'interférences avec d'autres puits et les contraintes imposées par les autorisations d'exploitation, par la qualité des eaux et par les conditions environnementales. Une méthodologie relativement simple d'estimation de la productivité qui prenne en compte tous ces facteurs a été mise au point. Cette méthodologie est basée surtout sur une analyse des données concernant le niveau piézométrique et le débit de prélèvement, quand ces données sont disponibles. De bonnes données opérationnelles sont particulièrement importantes quand il s'agit de puits dans des aquifères fissurés, libres et peu profonds, dans lesquels la performance réelle d'un puits peut varier considérablement de celle prédite à partir d'une approche plus analytique. Des données essentielles dans les processus d'estimation de la productivité sont l'identification d'un niveau piézométrique de pompage le plus profond possible et le recueil de données opérationnelles appropriées concernant le puits et l'aquifère. Bien qu'elle ait été développée pour des opérateurs gérant des captages en Grande-Bretagne, cette approche de l'estimation de la productivité des puits de captage d'eau potable à partir de données opérationnelles peut être appliquée à une large gamme de conditions hydrogéologiques en d'autres lieux. Resumen La productividad de un pozo de abastecimiento depende de varios factores, entre los que se incluyen las propiedades del pozo y del acuífero, la capacidad de la bomba, las obras de mantenimiento, la interferencia de otras captaciones y las restricciones impuestas por permisos legales, calidad del agua y aspectos ambientales. Se ha desarrollado una metodología relativamente simple para estimar la productividad de un pozo teniendo en cuenta todos los factores previamente mencionados. Esta metodología se basa principalmente en el análisis de niveles y caudales cuando estos datos están disponibles. Se requieren buenos datos de operación, principalmente cuando el pozo está situado en un acuífero de poco espesor, no confinado y en medio fracturado, donde la respuesta del sistema puede diferir enormemente de la predicción analítica. Un punto destacado en el estudio de productividad es la identificación del descenso máximo admisible. Aunque desarrollada para el Reino Unido, la metodología puede ser utilizada a un amplio rango de condiciones hidrogeológicas en otras zonas del mundo.
Cavana, Paola; Peano, Andrea; Petit, Jean-Yanique; Tizzani, Paolo; Perrot, Sébastien; Bensignor, Emmanuel; Guillot, Jacques
2015-01-01
Background Wipes containing chlorhexidine and azole derivates have been recommended for veterinary use. No study has been published about their activity against Malassezia pachydermatis. Hypothesis/Objectives To evaluate the in vivo and in vitro activity of wipes soaked in a chlorhexidine, climbazole and Tris-EDTA solution against Malassezia pachydermatis. Animals Five research colony shar-pei dogs. Methods Wipes were applied once daily onto the left axilla, left groin and perianal area (protocol A), and twice daily on the right axilla, right groin and umbilical region (protocol B) for 3 days. In vivo activity was evaluated by quantifying Malassezia colonies through contact plates on the selected body areas before and after wipe application. The activity of the solution in which the wipes were soaked was assessed in vitro by contact tests following the European Standard UNI EN 1275 guidelines. Results Samples collected after wipe application showed a significant and rapid reduction of Malassezia yeast CFU. No significant difference in the Malassezia reduction was found between protocols A and B. In vitro assay showed 100% activity against Malassezia yeasts after a 15 min contact time with the wipe solution. Conclusions and clinical importance Wipes containing chlorhexidine, climbazole and Tris-EDTA substantially reduced the M. pachydermatis population on the skin of dogs. The results, although this was an uncontrolled study performed on a small number of dogs, suggest that these wipes may be useful for topical therapy of Malassezia dermatitis involving the lips, paws, perianal area and skin folds. Résumé Contexte Des lingettes contenant de la chlorhexidine et des dérivésazolés ont été recommandés en médicine vétérinaire. Aucune étude n'a été publiée sur leur activité contre Malassezia pachydermatis. Hypothèses/Objectifs Evaluer l'activité in vivo et in vitro de lingettes imprégnées d'une solution de chlorhexidine, climbazole et Tris-EDTA contre Malassezia pachydermatis. Sujets Cinq colonies de shar-pei de recherche. Méthodes Les lingettes ont été appliquées une fois par jour au niveau du pli axillaire gauche, le pli inguinal droit et de la zone périanale(protocole A) et deux fois par joursur le pli axillaire droit, le inguinal droit et l'ombilic (protocole B) pendant 3 jours. L'activité in vivo a été évaluée par quantification des colonies de Malassezia par disques de contact sur les zones corporelles choisies avant et après application des lingettes. L'activité de la solution d'imprégnation des lingettes a été testée in vitro par tests de contact suivant les recommandations de l'European Standard UNI EN 1275. Résultats Les échantillons prélevés après application ont montré une diminution importante et rapide des CFU des levures Malassezia. Aucune différence significative dans la diminution des Malassezia n'a été mise en évidence entre les protocoles A et B. Des tests in vitro ont montré 100% d'activité contre les Malassezia après un temps de contact de 15 minutes avec la solution des lingettes. Conclusions et importance Clinique Les lingettes contenant la chlorhexidine, le climbazole et le Tris-EDTA réduisent substantiellement la population de M. pachydermatis sur la peau des chiens. Les résultats, bien qu'il s'agisse d'une étude non contrôlée réalisée sur un faible nombre de chiens, suggère que ces lingettes peuvent être utiles en traitement local de la dermatite à Malassezia des lèvres, des pattes, du périnée et des plis cutanés. Resumen Introducción las gasas que contienen clorhexidina y derivados de azol son recomendadas para uso veterinario. No se ha publicado ningún estudio acerca su actividad contra Malassezia paquidermatis. Hipótesis/Objetivos evaluar la actividad in vivo e in vitro de las gasas con clorhexidina, climbazol y soluciónb Tris-EDTA frente a Malassezia pachydermatis Animales cinco colonias de investigación de perros Sharpei. Métodos las gasas se aplicaron una vez al día en la axila izquierda, zona inguinal izquierda, y zona perianal (protocolo A), y dos veces al día en la axila derecha, zona inguinal derecha, y región umbilical (protocolo B) durante tres días. La actividad in vivo se evaluó mediante cuantificación de las colonias de Malassezia en placas de contacto de zonas seleccionadas del cuerpo antes y después de la aplicación de las gasas. La actividad de la solución en las que las gasas se empaparon se evaluó in vitro mediante pruebas de contacto siguiendo los estándares europeos UNI EN 1275. Resultados las muestras recogidas tras la aplicación de las gasas mostraron una reacción rápida y significativa de las colonias de Malassezia. No hubo significativas en la reducción de Malassezia en los dos protocolos. El ensayo in vitro demostró una actividad del 100% frente a Malassezia tras 15 minutos de contacto con la solución de las gasas. Conclusiones e importancia clínica las gasas que contienen clorhexidina, climbazol y Tris-EDTA reducen sustancialmente la población de Malassezia paquidermatis en la piel de perros. Aunque este era un estudio no controlado y desarrollado en un pequeño número de perros, los resultados sugieren que estas gasas pueden ser útiles para la terapia tópica de dermatitis producida por Malassezia en zonas de los labios, almohadillas plantares, y zonas perianales y pliegues de la piel. Zusammenfassung Hintergrund Feuchttücher, die Chlorhexidinund Azolderivate beinhalten, werden für den veterinärmedizinischen Gebrauch empfohlen. Es gibt keine Studie über ihre Wirkung im Einsatz gegen Malasseziapachydermatis. Hypothese/Ziele Eine Evaluierung der in vivo und der in vitro Aktivität dieser Feuchttücher in einer Chlorhexidin, Climbazol und Tris-EDTA Lösung gegen Malasseziapachydermatis. Tiere Fünf Shar-Peis aus einer Versuchstierkolonie. Methoden Die Feuchttücher wurden einmal täglich in der linken Achsel, in der linken Inguinalgegend und perianal (Protokol A) angewendet, und zweimal täglich in der rechten Achsel, in der rechten Inguinalgegend und umbilikal (Protokol B); beide Protokolle wurden 3 Tage lang durchgeführt. Die in vivo Aktivität wurde durch die Quantifizierung von Malassezienkolonien durch Kontaktplatten an den ausgewählten Körperstellen vor und nach Verwendung der Feuchttücher beurteilt. Die Aktivität der Lösung, in der die Feuchttücher getaucht waren, wurde in vitro mittels Kontakttest, den European Standard UNI EN 1275 Richtlinienfolgend, beurteilt. Ergebnisse Die Proben, die nach Anwendung der Feuchttücher genommen wurden, zeigten eine signifikante und rasche Abnahme der Malassezienhefen CFU. Zwischen den Protokollen A und B wurden keine signifikanten Unterschiede bei der Reduktion der Malassezien gefunden. Der in vitro Test zeigte nach einer 15 minütigen Kontaktzeit mit der Feuchtlösung eine 100%ige Wirkung gegen Malassezien. Schlussfolgerungen und klinische Bedeutung Feuchttücher, die Chlorhexidin, Climbazol und Tris-EDTA enthalten, reduzierten die M. pachydermatisPopulation auf der Haut der Hunde signifikant. Obwohl es sich um eine unkontrollierte Studie handelte, die an einer kleinen Zahl von Hunden durchgeführt wurde, weisen die Ergebnisse darauf hin, dass diese Feuchttücher für eine topische Behandlung der Malasseziendermatitis der Lippen, der Pfoten, der Perianalgegend und der Hautfaltennützlich sein könnten. PMID:26083147
Laser effects in the manipulation of human eggs and embryos for in vitro fertilization.
Tadir, Yona; Douglas-Hamilton, Diarmaid H
2007-01-01
Gamete manipulations using laser micro beams were introduced in 1991 and testing its application for assisted hatching occurred shortly thereafter. This procedure has now become an accepted modality of penetrating or reducing the thickness of the zona pellucida in human in vitro fertilization (IVF). Lasers used in earlier work are summarized. Although the earliest lasers used pulses as long as 15 ms, the simplest and safest laser presently used in this application is the high-power 1480-nm In GaAsP diode, used in pulses with duration typically < 1 ms. Since prevention of damage to the blastomeres is essential, we specifically discuss this system with particular attention to safety considerations. The laser operates by its thermal effect on the zona pellucida, and the implications for embryo safety are discussed in detail. A thermal model is derived using numerical analysis and the effect on the embryo of laser beam power and pulse duration is indicated. Typical recommended protocols and operating values for various applications in the human IVF laboratory are given.
NASA Astrophysics Data System (ADS)
McCoy, Michael J.; Habermann, Timothy J.; Hanke, Craig J.; Adar, Fran; Campbell, William B.; Nithipatikom, Kasem
1999-04-01
We developed a confocal Raman microspectroscopic technique to study ligand-receptor bindings in single cells using Raman-labeled ligands and surface-enhanced Raman scattering (SERS). The adrenal zona glomerulosa (ZG) cells were used as a model in this study. ZG cells have a high density of angiotensin II (AII) receptors on the cellular membrane. There are two identified subtypes of AII receptors,namely AT1 and AT2 receptors. AII is a peptidic hormone, which upon binding to its receptors, stimulates the release of aldosterone from ZG cells. The cellular localization of these receptors subtypes was detected in single ZG cells by using immunocomplexation of receptors with specific antibodies and confocal Raman microspectroscopy. In the binding study, we used biotin-labeled AII to bind to its receptors in ZG cells. Then, avidin and Raman-labeled AII. The binding was measure directly on the single ZG cells. The results showed that the binding was displaced with unlabeled AII and specific AII antagonists. This is a rapid and sensitive technique for detection of cellular ligand bindings as well as antagonists screening in drug discovery.
A Flexure-Guided Piezo Drill for Penetrating the Zona Pellucida of Mammalian Oocytes.
Johnson, Wesley; Dai, Changsheng; Liu, Jun; Wang, Xian; Luu, Devin K; Zhang, Zhuoran; Ru, Changhai; Zhou, Chao; Tan, Min; Pu, Huayan; Xie, Shaorong; Peng, Yan; Luo, Jun; Sun, Yu
2018-03-01
Mammalian oocytes such as mouse oocytes have a highly elastic outer membrane, zona pellucida (ZP) that cannot be penetrated without significantly deforming the oocyte, even with a sharp micropipette. Piezo drill devices leverage lateral and axial vibration of the micropipette to accomplish ZP penetration with greatly reduced oocyte deformation. However, existing piezo drills all rely on a large lateral micropipette vibration amplitude ( 20 ) and a small axial vibration amplitude (0.1 ). The very large lateral vibration amplitude has been deemed to be necessary for ZP penetration although it also induces larger oocyte deformation and more oocyte damage. This paper reports on a new piezo drill device that uses a flexure guidance mechanism and a systematically designed pulse train with an appropriate base frequency. Both simulation and experimental results demonstrate that a small lateral vibration amplitude (e.g., 2 ) and an axial vibration amplitude as large as 1.2 were achieved. Besides achieving 100% effectiveness in the penetration of mouse oocytes (n = 45), the new piezo device during ZP penetration induced a small oocyte deformation of 3.4 versus larger than 10 using existing piezo drill devices.
Human sperm chromosome analysis after subzonal sperm insemination of hamster oocytes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cozzi, J.
1994-09-01
Sperm microinjection techniques, subzonal sperm insemination (SUZI) and intracytoplasmic sperm injection (ICSI), have achieved a wide spread clinical application for the treatment of male infertility. To date, only one study has focused on sperm karyotypes after microinjection. Martin et al. reported a very high incidence of abnormal human sperm complements after ICSI into hamster oocytes. In the present study, are reported the first human sperm karyotypes after SUZI of hamster oocytes. Spermatozoa from two control donors were treated by calcium ionophore A23187 and injected under the zona of hamster eggs. The microinjected eggs were then cultured for cytogenetic analysis ofmore » the pronuclei. Out of 47 analyzed sperm chromosome metaphases, 5 (10.6%) were abnormal, 4 (8.5%) were hypohaploid and 1 (2.1%) had a structural abnormality. The sex ratio was not significantly different from the expected 1:1 ratio. Rates of chromosomal abnormalities in microinjected spermatozoa were similar to those observed in spermatozoa inseminated with zona free eggs, suggesting that SUZI procedure per se does not increase sperm chromosomal abnormalities.« less
Mejia, Christian R.; Valladares-Garrido, Mario J.; Romero, Brian M.; Valladares-Garrido, Danai; Linares-Reyes, Edgardo
2018-01-01
Introducción la retención laboral es un tema de suma importancia, porque se requiere de profesionales en el primer nivel de atención (PNA). El objetivo fue determinar si los accidentes laborales se asociaron al desánimo de los médicos para trabajar en el PNA de Lima, Perú. Métodos estudio transversal analítico de datos secundarios de una base de datos generada de una encuesta a médicos que realizaron su Servicio Rural y Urbano-Marginal en Salud (SERUMS). Se incluyó solo a los médicos que manifestaron al inicio del SERUMS que podían trabajar en el PNA de Lima. Se definió como cambio de intención de trabajo en el PNA a los que finalizando el SERUMS refirieron que ya no deseaban laborar en Lima. Esto se asoció según si tuvieron un accidente laboral y se ajustó por otras variables. Resultados de los 124 médicos el 63% fueron hombres (78). La mediana de edad fue de 26 años (rango intercuartílico: 25-27 años). Después de su SERUMS, el 12% (15) manifestó que cambió su interés y que deseaba trabajar en la capital. En el análisis multivariado, haber tenido un accidente laboral disminuyó la frecuencia del cambio de intención de trabajo en el PNA (RPa: 0.28, IC 95%: 0.14-0.54, p < 0,001), ajustado por ocho variables. Conclusiones en un estudio previo los accidentes laborales disminuyeron la frecuencia de trabajar en provincias, pero nuestro estudio dice lo contrario, posiblemente por la percepción de que un trabajo en la capital del país permite estar más cerca de los servicios para ser atendido en caso de cualquier emergencia. PMID:29190859
Disinfection of contaminated water by using solar irradiation.
Caslake, Laurie F; Connolly, Daniel J; Menon, Vilas; Duncanson, Catriona M; Rojas, Ricardo; Tavakoli, Javad
2004-02-01
Contaminated water causes an estimated 6 to 60 billion cases of gastrointestinal illness annually. The majority of these cases occur in rural areas of developing nations where the water supply remains polluted and adequate sanitation is unavailable. A portable, low-cost, and low-maintenance solar unit to disinfect unpotable water has been designed and tested. The solar disinfection unit was tested with both river water and partially processed water from two wastewater treatment plants. In less than 30 min in midday sunlight, the unit eradicated more than 4 log10 U (99.99%) of bacteria contained in highly contaminated water samples. The solar disinfection unit has been field tested by Centro Panamericano de Ingenieria Sanitaria y Ciencias del Ambiente in Lima, Peru. At moderate light intensity, the solar disinfection unit was capable of reducing the bacterial load in a controlled contaminated water sample by 4 log10 U and disinfected approximately 1 liter of water in 30 min.
Caracterización espectroscópica de hielos de interés atmosférico y astrofísico
NASA Astrophysics Data System (ADS)
Escribano, R.
En años recientes se ha incrementado el estudio de procesos físicos y químicos que tienen lugar en la superficie o el interior de hielos, tanto en medios astrofísicos como en la atmósfera terrestre y en otros cuerpos del sistema solar. Se ha comprobado que las partículas heladas actúan como catalizadores de reacciones químicas, que no ocurrirían en su ausencia. En la atmósfera terrestre, es bien conocida la importancia de partículas de hidratos de ácido nítrico, formando las llamadas nubes estratosféricas polares, en los procesos de destrucción de ozono estratosférico. En hielos astrofísicos, átomos como H, C, N y O pueden adherirse o introducirse en la estructura cristalina o amorfa del hielo, y dar lugar a reacciones de formación de moléculas evitando su barrera de activación. Existen partículas heladas en el medio interestelar formando parte de las llamadas nubes moleculares densas y frías, con valores del orden de 106 átomos de H por cm3 y temperaturas entre 3 y 90 K. Alrededor de protoestrellas, pueden formarse hielos de distinta composición, polares o apolares, en las zonas de alejamiento y temperatura decreciente a partir del núcleo caliente. Por su parte, los cometas están formados por un núcleo de hielo y rocas, sobre el que se encuentran adheridas moléculas gaseosas, y una cola, formada por los gases liberados por efecto del calentamiento debido a la radiación solar incidente. En nuestro sistema solar, los polos de La Tierra y de Marte están cubiertos de hielo, así como la mayoría de los cuerpos externos. Los satélites de Júpiter han sido estudiados detalladamente, y se han encontrado en ellos, y en Tritón (satélite de Neptuno), hielos de moléculas como SON2, CO2, N2, CH4 y otros. Para la caracterización espectroscópica de estos hielos se precisan medidas en el laboratorio, aún conociendo la imposibilidad intrínseca de reproducir exactamente las condiciones en que se formaron y se encuentran en los medios astrofísicos. El montaje experimental requiere un sistema que permita alcanzar bajas presiones y temperaturas, formado usualmente por una cámara en cuyo interior se forman películas de hielo de la composición deseada, depositadas sobre un sustrato inerte. Las películas pueden ser a continuación tratadas por diversas técnicas, tales como irradiación UV, bombardeo con electrones o iones, calentamiento y enfriamiento, etc. Habitualmente todos los procesos se controlan por espectroscopía de infrarrojo. La radiación proveniente de un espectrómetro se hace incidir sobre la muestra y se extrae de la cámara mediante ventanas, y se enfoca posteriormente sobre el detector. En el laboratorio de Física Molecular del Instituto de Estructura de la Materia disponemos de un montaje experimental diseñado para el estudio de partículas de hielo similares a las formadas en las nubes estratosféricas polares de nuestra atmósfera. El montaje es similar al descrito anteriormente, excepto en lo que se refiere a las condiciones de presión y temperatura, que son menos estrictas en nuestros experimentos. La extensión de estas condiciones de trabajo a las requeridas en medios astrofísicos es una posibilidad a discutir. Por otra parte, disponemos de un método de cálculo de estructuras periódicas, basado en el programa SIESTA (acrónimo de Spanish Initiative for Electronic Simulations of Thousands of Atoms), que ha proporcionado excelentes resultados en lo relativo a la determinación de estructuras cristalinas y predicción de su espectro infrarrojo, en los sistemas estudiados hasta la fecha, es decir, los hidratos de ácido nítrico de interés atmosféricos. Su aplicación para el estudio de hielos de relevancia astrofísica podría ser del máximo interés.
NASA Astrophysics Data System (ADS)
Dim, J. R.; Sakura, Y.; Fukami, H.; Miyakoshi, A.
2002-03-01
In porous sediments of the Ishikari Lowland, there is a gradual increase in the background geothermal gradient from the Ishikari River (3-4 °C 100 m-1) to the southwest highland area (10 °C 100 m-1). However, the geothermal gradient at shallow depths differs in detail from the background distribution. In spite of convective heat-flow loss generally associated with groundwater flow, heat flow remains high (100 mW m-2) in the recharge area in the southwestern part of the Ishikari basin, which is part of an active geothermal field. In the northeastern part of the lowland, heat flow locally reaches 140 mW m-2, probably due to upward water flow from the deep geothermal field. Between the two areas the heat flow is much lower. To examine the role of hydraulic flow in the distortion of the isotherms in this area, thermal gradient vs. temperature analyses were made, and they helped to define the major components of the groundwater-flow system of the region. Two-dimensional simulation modeling aided in understanding not only the cause of horizontal heat-flow variations in this field but also the contrast between thermal properties of shallow and deep groundwater reservoirs. Résumé. Dans les sédiments poreux des basses terres d'Ishikari, on observe une augmentation graduelle du gradient géothermal général depuis la rivière Ishikari (3-4 °C 100 m-1) vers la zone élevée située au sud-ouest (10 °C 100 m-1). Toutefois, le gradient géothermal aux faibles profondeurs diffère dans le détail de la distribution générale. Malgré la perte de flux de chaleur par convection, généralement associée aux écoulements souterrains, le flux de chaleur reste élevé (100 mW m-2) dans la zone de recharge de la partie sud-ouest du bassin de l'Ishikari, qui appartient à un champ géothermal actif. Dans la partie nord-est des basses terres, le flux de chaleur atteint localement 140 mW m-2, probablement à cause d'un écoulement souterrain ascendant depuis le champ géothermal profond. Entre les deux zones, le flux de chaleur est beaucoup plus faible. Afin de déterminer le rôle du flux d'eau souterraine dans la distorsion des isothermes dans cette zone, des analyses du gradient thermal en fonction de la température ont été réalisées elles ont permis de définir les composantes majeures du système aquifère régional. Une modélisation deux-dimensionnelle pour la simulation a ensuite contribué à la compréhension non seulement de la cause des variations horizontales du flux de chaleur dans cette région, mais également du contraste entre les propriétés des réservoirs superficiel et profond. Resumen. En los sedimentos porosos de las tierras bajas de Ishikari, hay un incremento gradual en el gradiente geotérmico desde el río Ishikari (3-4 °C 100 m-1) hacia la zona elevada del sudoeste (10 °C 100 m-1). Sin embargo, el gradiente geotérmico a profundidades someras difiere de la distribución de fondo. A pesar de las pérdidas por el flujo convectivo de calor asociadas generalmente al flujo de aguas subterráneas, el flujo de calor permanece elevado (100 mW m-2) en el área de recarga, hacia el sudoeste de la cuenca del Ishikari, la cual pertenece a un campo geotérmico activo. Al nordeste de las tierras bajas, el flujo de calor alcanza 140 mW m-2, probablemente por el flujo ascendente de agua procedente del campo geotérmico profundo. Entre ambas áreas, el flujo de calor es mucho menor. Para examinar el papel del flujo hidráulico en la distorsión de las isotermas de esta región, se ha comparado el gradiente térmico con la temperatura, con lo cual se ha podido definir los componentes mayoritarios del sistema de flujo de las aguas subterráneas. El uso de modelos bidimensionales ha servido para comprender no sólo del origen de las variaciones horizontales del flujo de calor en este campo, sino también el contraste entre las propiedades térmicas de los reservorios someros y profundos de aguas subterráneas.
Monitoring artificially stimulated fluid movement in the Cretaceous Dakota aquifer, western Kansas
NASA Astrophysics Data System (ADS)
Macfarlane, Allen; Förster, Andrea; Merriam, Daniel; Schrötter, Jörg; Healey, John
2002-10-01
Aquifer properties can be evaluated by monitoring artificially stimulated fluid movements between wells, if the fluid is heated. Changes in the temperature profile recorded in observation wells indicate the flow path of the heated fluid, which in effect acts as a tracer. A fluid-flow experiment in the Cretaceous Dakota Formation at the Hodgeman County site, west-central Kansas, demonstrated the advantage of using the distributed optical-fiber temperature sensing method for monitoring transient temperature conditions in this hydrological application. The fluid flow in the aquifer was increased by producing water from a pumping well and injecting heated water in an injection well 13 m (43 ft) distant from the pumping well. The time-temperature series data obtained and compared with results from previous pumping tests point to interwell heterogeneity of the aquifer and to a zone in the sandstone aquifer of high hydraulic conductivity. However, the experiment would have allowed further clarification of aquifer heterogeneity and thermal properties if at least one observation well had been present between the injection and production wells. Résumé. Les caractéristiques d'un aquifère peuvent être évaluées en effectuant un suivi des mouvements du fluide stimulés artificiellement entre des puits, si le fluide est chauffé. Les variations de profils de température enregistrés dans les puits d'observation donnent des informations sur les directions d'écoulement du fluide chauffé, qui en fait se comporte comme un traceur. Réalisée dans la formation crétacée de Dakota, sur le site du Comté de Hodgeman (centre-ouest du Kansas), une expérience a démontré l'intérêt d'utiliser la méthode de détection distribuée de température par fibres optiques pour suivre les variations de température dans cette application hydrologique. L'écoulement du fluide dans l'aquifère a été favorisé en extrayant de l'eau par pompage et en injectant de l'eau chaude dans un puits d'injection distant de 13 m du puits de pompage. La chronique de température obtenue et comparée aux résultats d'essais de pompage précédents fait apparaître l'hétérogénéité de l'aquifère entre les puits et l'existence d'une zone de forte conductivité hydraulique dans l'aquifère de grès. Toutefois, l'expérience aurait fourni des éclaircissements supplémentaires sur l'hétérogénéité de l'aquifère et sur ses propriétés thermiques si au moins un puits d'observation avait été placé entre le puits d'injection et le puits de pompage. Resumen. Se puede evaluar las propiedades de un acuífero mediante la observación del movimiento de un fluido, calentado artificialmente, entre pozos. Los cambios registrados en el perfil de temperatura de los pozos de observación indican la trayectoria del fluido calentado, el cual actúa como un trazador. Un experimento de este tipo que se realizó en la formación cretácica de Dakota, en el condado de Hodgeman (porción occidental del centro de Kansas, Estados Unidos de América), demostró la ventaja de utilizar el método del sensor de temperatura con fibra óptica distribuída para medir condiciones transitorias de temperatura en esta aplicación hidrológica. El flujo del fluido en el acuífero aumentó con el bombeo de un pozo y la inyección de agua caliente en otro sondeo, que distaba 13 m (43 pies) del primero. Las series de temperatura obtenidas y comparadas con resultados de ensayos de bombeo previos resaltan la heterogeneidad del acuífero entre ambos pozos, así como la existencia de una zona de elevada conductividad hidráulica en el acuífero de la arenisca. Sin embargo, el experimento habría proporcionado más información sobre la heterogeneidad de la formación y sus propiedades termales si se hubiera dispuesto al menos de un punto de observación entre los pozos de inyección y bombeo.
Developmental kinetics of pig embryos by parthenogenetic activation or by handmade cloning.
Li, J; Li, R; Liu, Y; Villemoes, K; Purup, S; Callesen, H
2013-10-01
The developmental kinetics of pig embryos produced by parthenogenetic activation without (PAZF) or with (PAZI) zona pellucida or by handmade cloning (HMC) was compared by time-lapse videography. After cumulus cell removal, the matured oocytes were either left zona intact (PAZI) or were made zona free by pronase digestion (PAZF) before they were activated (PA). Other matured oocytes were used for HMC based on foetal fibroblast cells. On Day 0 (day of PA or reconstruction), the embryos were cultured for 7 days in vitro in our time-lapse system. Pictures were taken every 30 min, and afterwards, each cell cycle was identified for each embryo to be analysed. Results showed that the PA embryos (both PAZF and PAZI) had shorter first cell cycle compared with HMC (17.4. 17.8 vs 23.6 h), but had a longer time length from four cell to morula stages (57.9, 53.8 vs 44.9 h). However, at the second cell cycle, PAZF embryos needed shorter time, while PAZI embryos had similar time length as HMC embryos, and both were longer than PAZF (23.4, 24.8 vs 14.6 h). Both PAZF and PAZI embryos used similar time to reach the blastocyst stage, and this was later than HMC embryos. In addition, when all of these embryos were grouped into viable (developed to blastocysts) and non-viable (not developed to blastocysts), the only difference in the time length was observed on the first cell cycle (18.6 vs 24.5 h), but not on the later cell cycles. In conclusion, our results not only give detailed information regarding the time schedule of in vitro-handled pig embryos, but also indicate that the first cell cycle could be used as a selecting marker for embryo viability. However, to evaluate the effect of the produced techniques, the whole time schedule of the pre-implantation developmental kinetics should be observed. © 2013 Blackwell Verlag GmbH.
Effects of ultrashort gamete co-incubation time on porcine in vitro fertilization.
Almiñana, C; Gil, M A; Cuello, C; Parrilla, I; Roca, J; Vazquez, J M; Martinez, E A
2008-07-01
A reduction in co-incubation time has been suggested as an alternative method to reduce polyspermic fertilization. The aim of this study was to evaluate the effect of short periods of gamete co-incubation during pig in vitro fertilization. A total of 2,833 in vitro matured oocytes were inseminated with thawed spermatozoa and coincubated for 0.25, 1, 2, 3, 7, 10 min and 6h. The oocytes from the 0.25-10 min groups were washed three times in modified Tris-buffered medium (mTBM) medium to remove spermatozoa not bound to the zona and transferred to the same medium (containing no spermatozoa) until 6h of co-incubation time were completed. After 6h, presumptive zygotes from each group were cultured in NCSU-23 medium for 12-15 h to assess fertilization parameters. After each period of co-incubation, 45-50 oocytes from each group were stained with Hoechst-33342 and the number of spermatozoa bound to the zona was counted. Although the number of zona bound spermatozoa increased (p<0.05) with the co-incubation time, no increase was observed in penetration rates among groups from 2 min to 6h of co-incubation time (ranging from 53.5+/-2.8 to 61.3+/-2.6%). Similarly, the efficiency of fertilization reached a maximum for the 2 min of co-incubation group with values ranging between 32.3+/-2.4 and 41.9+/-2.5%. The reduction of co-incubation time did not affect the monospermy rate (range: 71.3+/-3.4-80.2+/-3.8%) and the mean number of spermatozoa/oocyte (range: 1.2+/-0.4-1.4+/-0.5). These results show that, under our in vitro conditions, high penetration rate can be obtained with co-incubation times as short as 2 min, although monospermy could not be improved using this strategy.
Maniero, Carmela; Garg, Sumedha; Zhao, Wanfeng; Johnson, Timothy Isaac; Zhou, Junhua; Gurnell, Mark; Brown, Morris J
2017-08-01
Heterogeneity among aldosterone-producing adenomas (APAs) has been highlighted by the discovery of somatic mutations. KCNJ5 mutations predominate in large zona fasciculata (ZF)-like APAs; mutations in CACNA1D , ATP1A1, ATP2B3 , and CTNNB1 are more likely to be found in small zona glomerulosa (ZG)-like APAs. Microarray comparison of KCNJ5 mutant versus wild-type APAs revealed significant differences in transcriptomes. NEFM , encoding a neurofilament subunit which is a D1R (dopamine D1 receptor)-interacting protein, was 4-fold upregulated in ZG-like versus ZF-like APAs and 14-fold more highly expressed in normal ZG versus ZF. Immunohistochemistry confirmed selective expression of NEFM (neurofilament medium) polypeptide in ZG and in ZG-like APAs. Silencing NEFM in adrenocortical H295R cells increased basal aldosterone secretion and cell proliferation; silencing also amplified aldosterone stimulation by the D1R agonist, fenoldopam, and inhibition by the D1R antagonist, SCH23390. NEFM coimmunoprecipitated with D1R, and its expression was stimulated by fenoldopam. Immunohistochemistry for D1R was mainly intracellular in ZG-like APAs but membranous in ZF-like APAs. Aldosterone secretion in response to fenoldopam in primary cells from ZF-like APAs was higher than in cells from ZG-like APAs. Transfection of mutant KCNJ5 caused a large reduction in NEFM expression in H295R cells. We conclude that NEFM is a negative regulator of aldosterone production and cell proliferation, in part by facilitating D1R internalization from the plasma membrane. Downregulation of NEFM in ZF-like APAs may contribute to a D1R/D2R imbalance underlying variable pharmacological responses to dopaminergic drugs among patients with APAs. Finally, taken together, our data point to the possibility that ZF-like APAs are in fact ZG in origin. © 2017 American Heart Association, Inc.
Orozco, María Marcela; Miccio, Luciano; Enriquez, Gustavo Fabián; Iribarren, Fabián Eduardo; Gürtler, Ricardo Esteban
2014-09-01
The transmission of pathogens between domestic dogs and generalist wildlife species may be modified by environmental degradation, biodiversity losses, host densities, and increased contact rates in remnant forest patches. A serologic survey of canine parvovirus (CPV) in rural domestic dogs and wild mammals was conducted in two neighboring rural areas (disturbed and protected) from Pampa del Indio, northeastern Argentina, between 2008 and 2011. A total of 174 domestic dogs and 26 wild mammals-4 crab-eating foxes (Cerdocyon thous), 3 crab-eating raccoons (Procyon cancrivorus), 17 white-eared opossums (Didelphis albiventris), and 2 gray four-eyed opossums (Philander opossum)-were examined for antibodies to CPV using a hemagglutination inhibition assay. Domestic dogs were numerous and their movements unrestricted. The main function of dogs differed significantly between areas, with more dogs used for herding or hunting around the protected area. The seroprevalence of antibodies to CPV in dogs from both areas was very high (93.9-94.6%) and increased steeply with age. Nearly all carnivores and marsupials showed high exposure to CPV. Although a higher exposure to CPV was expected in wild mammals from disturbed areas as a result of enhanced contact between dogs and wildlife, no significant differences were found between areas. To the authors' knowledge, this study is the first to document exposure to CPV of free-ranging Pr. cancrivorus, D. albiventris, and Ph. opossum, and include a detailed demographic study of the domestic dog populations living in the area. This study highlights that dogs and wildlife have potential opportunities for contact and shows that the edges of the protected area may be as suitable as other fragmented areas for the transmission of CPV. Rural domestic dogs may pose serious threats to the health and conservation of wild carnivores in both disturbed and protected areas, especially in the Gran Chaco, where habitat fragmentation is severely increasing.
Prediction uncertainty of plume characteristics derived from a small number of measuring points
NASA Astrophysics Data System (ADS)
French, H. K.; van der Zee, S. E. A. T. M.; Leijnse, A.
A small number of measuring points may inflict a bias on the characterisation of flow and transport based on field experiments in the unsaturated zone. Simulation of pure advective transport of a Gaussian plume through a setup of 30 regularly placed measuring points revealed regular temporal fluctuations about the real spatial moments. An irregular setup predicted both irregular fluctuations and larger discrepancies from the real value. From these considerations, a regular setup is recommended. Spatial moments were sensitive to the plume size relative to the distance between individual measuring points. To reduce prediction errors of the variance, the distance between the measuring points should be less than twice the standard deviation of the examined plume. The total size of the setup should cover several standard deviations of the plume to avoid mass being lost from the monitored area. Numerical simulations of a dispersing plume (comparing calculations based on 9000 nodes with 30 measuring points) revealed that vertical and horizontal centres of mass were predicted well at all degrees of heterogeneity, and the same was the case for horizontal variances. Vertical variances were more susceptible to prediction errors, but estimates were of the same order of magnitude as the real values. Résumé Lorsque l'on cherche à caractériser l'écoulement et le transport à partir d'expériences de terrain dans la zone saturée, il arrive qu'un petit nombre de points introduisent un biais. La simulation d'un transport purement advectif d'un panache gaussien au travers d'un ensemble de 30 points de mesures espacés régulièrement fait apparaître des variations temporelles régulières autour des moments spatiaux réels. Un ensemble irrégulier conduit à prédire à la fois des variations irrégulières et de plus grandes divergences par rapport à la valeur réelle. A partir de ces constations, un ensemble régulier est recommandé. Les moments spatiaux sont apparus sensibles à la dimension du panache en fonction de la distance entre les différents points de mesure. Afin de réduire les erreurs de prédiction de la variance, la distance entre les points de mesure doit être inférieure au double de l'écart-type du panache examiné. La dimension totale de l'ensemble doit couvrir une étendue de plusieurs écarts-types du panache pour éviter qu'une partie de la matière échappe à la zone surveillée. Des simulations numériques du panache en dispersion (les calculs de comparaison sont basés sur 9000 nœuds avec 30 points de mesure) montrent que le centre vertical et le centre horizontal de la matière dispersée ont été bien prédits à tous les degrés d'hétérogénéité, de même que pour les variances horizontales. Les variances verticales ont été plus sensibles aux erreurs de prédiction, mais les estimations étaient du même ordre de grandeur que les valeurs réelles. Resumen Un número pequeño de puntos de medida puede producir un sesgo en la caracterización en campo del flujo y transporte de solutos en la zona no saturada. La simulación de transporte advectivo (no difusivo) de un penacho Gaussiano a travs de un conjunto de 30 puntos de medida regularmente distribuidos revelan fluctuaciones temporales regulares de los momentos espaciales del penacho. Una distribución irregular de puntos de medida predijo a su vez fluctuaciones irregulares, más alejadas de la realidad, por lo que se recomienda el uso de esquemas de muestreo regulares. Los momentos espaciales fueron sensibles a la relación entre tamaño del penacho y distancia entre puntos de medida. Para reducir los errores en la predicción de la varianza, la distancia entre puntos de observación debe ser menor que dos veces la desviación estándar del penacho. El tamaño del área muestreada debe cubrir varias desviaciones estándar del penacho para evitar perder parte de la masa. Las simulaciones numricas en un penacho dispersivo, comparando los cálculos basados en 9000 nudos con las 30 medidas, mostraron que las posiciones de los centros de masa y las varianzas en dirección horizontal se predijeron bien independientemente del grado de heterogeneidad. Las varianzas verticales, sin embargo, fueron más susceptibles a errores de predicción, pero las estimaciones eran del mismo orden de magnitud que los valores reales.
NASA Astrophysics Data System (ADS)
Foster, Stephen; Garduno, Hector; Evans, Richard; Olson, Doug; Tian, Yuan; Zhang, Weizhen; Han, Zaisheng
The Quaternary Aquifer of the North China Plain is one of the world's largest aquifer systems and supports an enormous exploitation of groundwater, which has reaped large socio-economic benefits in terms of grain production, farming employment and rural poverty alleviation, together with urban and industrial water-supply provision. Both population and economic activity have grown markedly in the past 25 years. Much of this has been heavily dependent upon groundwater resource development, which has encountered increasing difficulties in recent years primarily as a result of aquifer depletion and related phenomena. This paper focuses upon the hydrogeologic and socio-economic diagnosis of these groundwater resource issues, and identifies strategies to improve groundwater resource sustainability. L'aquifère Quaternaire de la Plaine du Nord de la Chine est l'un des plus grands systèmes aquifères du monde; il permet une exploitation énorme d'eau souterraine, qui a permis des très importants bénéfices socio-économiques en terme de production de céréales, d'emplois ruraux et de réduction de la pauvreté rurale, en même temps que l'approvisionnement en eau potable et pour l'industrie. La population comme l'activité économique ont remarquablement augmenté au cours de ces 25 dernières années. Elles ont été sous la forte dépendance du développement de la ressource en eau souterraine, qui a rencontré des difficultés croissantes ces dernières années, du fait du rabattement de l'aquifère et des phénomènes associés. Cet article est consacré aux diagnostiques hydrogéologique et socio-économique des retombées de cette ressource en eau souterraine; il identifie les stratégies pour améliorer la pérennité des ressources en eau souterraine. El acuífero cuaternario de la Llanura Septentrional de China es uno de los mayores sistemas acuíferos del mundo y soporta una enorme explotación de su agua subterránea, las cuales han originado grandes beneficios socioeconómicos en términos de producción de grano, empleo en agricultura y mitigación de la pobreza rural, además de proveer agua para abastecimiento urbano e industria. Tanto la población como la actividad económica han crecido mucho en los últimos 25 años con una gran dependencia de las aguas subterráneas, que ha encontrado dificultades recientes por la explotación intensiva del acuífero y fenómenos relacionados. Este artículo se centra en la diagnosis hidrogeológica y socioeconómica de los problemas relacionados con las aguas subterráneas e identifica estrategias para mejorar la sustentabilidad de este recurco.
Rodríguez, Claudia S; Crocco, Liliana; Altamirano, Alejandra; Catalá, Silvia
2013-02-01
Triatomines undergo morphological changes as an adaptive response to different habitats (wild, peridomestic, domestic, laboratory). The characterization of the antennal phenotype provides information on intraspecific variation caused by geographical origin and/or habitat. Triatoma patagonica Del Ponte, 1929 is known to occur in peridomiciles of rural areas in Argentina, where it also invades non-colonized dwellings. Here we describe and compare the antennal phenotype of T. patagonica in populations of different geographic origin, and explore possible modifications induced by laboratory rearing with the aim of investigating the range of phenotypic variation of the species for the first time. Sixty antennas of adult males and females of T. patagonica belonging to two peridomiciliary populations of different geographical origin were analyzed. Four types of sensilla were observed in three antennal segments, showing sexual dimorphism in the species. The multivariate analysis separated the populations of similar habitat (peridomicile) but different geographical origin, without showing differences between the peridomiciliary and laboratory populations of the same geographical origin. These results suggest phenotypic plasticity in T. patagonica, which would allow the species to adapt to a wide range of habitats without having a close association with a given host and its environment. The range of antennal phenotypic variation of T. patagonica would also be an indicator of its current stage of adaptation to the human environment. Copyright © 2012 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Blanch, Juan M. Lope
1975-01-01
Before creating a linguistic map of Mexican dialects, it is necessary to determine the dialect regions of the country. An extensive questionnaire must be written and distributed to collect data from a representative sample of the population for an accurate picture of the language. (CK) (Text in Spanish.)
Groundwater-flow modeling in the Yucatan karstic aquifer, Mexico
NASA Astrophysics Data System (ADS)
González-Herrera, Roger; Sánchez-y-Pinto, Ismael; Gamboa-Vargas, José
2002-09-01
The current conceptual model of the unconfined karstic aquifer in the Yucatan Peninsula, Mexico, is that a fresh-water lens floats above denser saline water that penetrates more than 40 km inland. The transmissivity of the aquifer is very high so the hydraulic gradient is very low, ranging from 7-10 mm/km through most of the northern part of the peninsula. The computer modeling program AQUIFER was used to investigate the regional groundwater flow in the aquifer. The karstified zone was modeled using the assumption that it acts hydraulically similar to a granular, porous medium. As part of the calibration, the following hypotheses were tested: (1) karstic features play an important role in the groundwater-flow system; (2) a ring or belt of sinkholes in the area is a manifestation of a zone of high transmissivity that facilitates the channeling of groundwater toward the Gulf of Mexico; and (3) the geologic features in the southern part of Yucatan influence the groundwater-flow system. The model shows that the Sierrita de Ticul fault, in the southwestern part of the study area, acts as a flow barrier and head values decline toward the northeast. The modeling also shows that the regional flow-system dynamics have not been altered despite the large number of pumping wells because the volume of water pumped is small compared with the volume of recharge, and the well-developed karst system of the region has a very high hydraulic conductivity. Résumé. Le modèle conceptuel classique de l'aquifère karstique libre de la péninsule du Yucatan (Mexique) consiste en une lentille d'eau douce flottant sur une eau salée plus dense qui pénètre à plus de 40 km à l'intérieur des terres. La transmissivité de l'aquifère est très élevée, en sorte que le gradient hydraulique est très faible, compris entre 7 et 10 mm/km dans la plus grande partie du nord de la péninsule. Le modèle AQUIFER a été utilisé pour explorer les écoulements souterrains régionaux dans cet aquifère. La zone karstifiée a été modélisée en posant l'hypothèse qu'il fonctionne hydrauliquement comme un milieu poreux granulaire. Au cours de la calibration, les hypothèses suivantes ont été testées: (1) les phénomènes karstiques jouent un rôle important dans le système aquifère, (2) un anneau ou une ceinture de dépressions dans la région est la manifestation d'une zone à forte transmissivité qui permet l'écoulement en conduits de l'eau souterraine en direction du Golfe du Mexique, et (3) la situation géologique dans la partie sud du Yucatan détermine les écoulements souterrains. Le modèle montre que la faille de la Sierrita de Ticul, dans la partie sud-ouest de la région étudiée, joue le rôle de barrière et que les valeurs de la piézométrie décroissent en direction du nord-est. La modélisation montre également que la dynamique du système aquifère à l'échelle régionale n'a pas été modifiée malgré le grand nombre de puits de pompage, parce que le volume pompé est faible en comparaison du volume de recharge; en outre, le réseau karstique très bien développé dans cette région possède une très forte conductivité hydraulique. Resumen. El modelo conceptual actual del acuífero cárstico no confinado de la Península de Yucatán (México) es el de un lentejón de agua dulce flotando sobre agua salada, más densa, la cual penetra más de 40 kilómetros tierra adentro. Debido a la alta conductividad hidráulica del acuífero, existe un gradiente hidráulico muy bajo cuyo rango está entre 7 y 10 milímetros por kilómetro en la porción norte de la península. Se utilizó el código AQUIFER para investigar el sistema de flujo de las aguas subterráneas a escala regional en el acuífero. La zona carstificada se modeló suponiendo que actúa hidráulicamente como un medio poroso granular. Como parte de la calibración, se probaron las siguientes hipótesis: (1) las características cársticas desempeñan un papel importante en el sistema de flujo de agua subterránea (2) un anillo o cinturón de sumideros en el área es una manifestación de una zona de alta transmisividad que conduce las aguas subterráneas hacia el Golfo de México y (3) las propiedades geológicas de la porción sur de Yucatán influyen en el sistema de flujo de agua subterránea. El modelo demostró que la falla de la Sierrita de Ticul, situada en el sudoeste de la zona de estudio, actúa como una barrera al flujo, y que los niveles piezométricos disminuyen hacia el nordeste. La modelación también mostró que la dinámica del sistema de flujo regional no ha sido alterada a pesar de la gran cantidad de captaciones, ya que el volumen extraído es pequeño en comparación con la recarga al acuífero además, el sistema cárstico de la región, bien desarrollado, posee una conductividad hidráulica muy elevada.
Phosphorylation of zona occludens-2 by protein kinase C epsilon regulates its nuclear exportation.
Chamorro, David; Alarcón, Lourdes; Ponce, Arturo; Tapia, Rocio; González-Aguilar, Héctor; Robles-Flores, Martha; Mejía-Castillo, Teresa; Segovia, José; Bandala, Yamir; Juaristi, Eusebio; González-Mariscal, Lorenza
2009-09-01
Here, we have analyzed the subcellular destiny of newly synthesized tight junction protein zona occludens (ZO)-2. After transfection in sparse cells, 74% of cells exhibit ZO-2 at the nucleus, and after 18 h the value decreases to 17%. The mutation S369A located within the nuclear exportation signal 1 of ZO-2 impairs the nuclear export of the protein. Because Ser369 represents a putative protein kinase C (PKC) phosphorylation site, we tested the effect of PKC inhibition and stimulation on the nuclear export of ZO-2. Our results strongly suggest that the departure of ZO-2 from the nucleus is regulated by phosphorylation at Ser369 by novel PKCepsilon. To test the route taken by ZO-2 from synthesis to the plasma membrane, we devised a novel nuclear microinjection assay in which the nucleus served as a reservoir for anti-ZO-2 antibody. Through this assay, we demonstrate that a significant amount of newly synthesized ZO-2 goes into the nucleus and is later relocated to the plasma membrane. These results constitute novel information for understanding the mechanisms that regulate the intracellular fate of ZO-2.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tompkins, R.G.; Schnitzer, J.J.; Yarmush, M.L.
1988-09-01
A recently developed technique of absolute quantitative light microscopic autoradiography of /sup 125/I-labeled proteins in biologic specimens was used to measure /sup 125/I-low density lipoprotein (/sup 125/I-LDL) concentration levels in various tissues of the squirrel monkey after 30 minutes of in vivo LDL circulation. Liver and adrenal cortex exhibited high /sup 125/I-LDL concentrations, presumably because of binding to specific cell surface receptors and/or internalization in vascular beds with high permeability to LDL. High tissue concentrations of LDL were associated with the zona fasciculata and reticularis of the adrenal cortex and the interstitial cells of Leydig in the testis; significantly lowermore » levels of /sup 125/I-LDL were observed in the adrenal medulla, the zona glomerulosa, and germinal centers of the testis. Contrary to previous reports, low /sup 125/I-LDL concentrations were observed throughout the gastrointestinal tract and in lymph nodes. In addition, multiple arterial intramural focal areas of high /sup 125/I-LDL concentrations were identified in arteries supplying the adrenal gland, lymph node, small bowel, and liver.« less
Microanatomical diversification of the zona pellucida in aplochelioid killifishes.
Thompson, A W; Furness, A I; Stone, C; Rade, C M; Ortí, G
2017-07-01
This study investigates zona pellucida (ZP) ultrastructure in fertilized eggs of annual killifishes (suborder Aplocheiloidei), a group of highly specialized fishes that are able to survive desiccation for several weeks to months before they hatch. Little is known about ZP or chorionic ultrastructure sustaining these life-history modes, so scanning electron microscopy (SEM) was used to describe this trait in a large number of aplocheiloids with a focus on the family Rivulidae and the genus Hypsolebias. New images of ZP ultrastructure for 52 aplocheiloid species are provided, more than doubling the number characterized thus far. The evolution of chorionic structure within this group is studied using these new data. Characters were coded into a morphological matrix and optimized onto a consensus phylogeny to assess phylogenetic signal and reconstruct ancestral character states. Although ZP characters seem highly homoplastic and exhibit a large amount of structural convergence among lineages, aplocheiloid killifishes have evolved a number of unique structures associated with the chorion. Some annual species seem to have lost long filaments because eggs are deposited in the soil instead of being adhered to aquatic plants. © 2017 The Fisheries Society of the British Isles.
Targeting the zona pellucida for immunocontraception: a minireview.
Tesarik, J
1995-12-01
This minireview summarizes the main data relevant to the development of contraceptive vaccines based on zona pellucida (ZP) antigens, as well as the pros and the cons of this immunocontraceptive strategy. Even though the antifertility efficacy of anti-ZP antibodies in humans is not corroborated by a clear relationship between spontaneous autoimmunization against the ZP and infertility, passive and active immunization studies in laboratory animals have provided convincing results. The contraceptive action of anti-ZP antibodies, targeting events situated upstream of gamete fusion, is devoid of potential ethical concerns related to the destruction of early embryos. The high protein content of the mammalian ZP, knowledge of the complete amino acid sequence of the major ZP proteins, and the high degree of sequence homology between individual species all favour the rapid advancement of anti-ZP vaccine projects. However, certain sequences of ZP proteins, when incorporated into the vaccine construct, activate CD4+ T cells of the recipient organism to direct a cellular immune attack (autoimmune oophoritis) to other functionally relevant ovarian components (primordial follicles, steroidogenic cells). The search for the optimal combination of B cell and T cell epitopes in the vaccine construct will hopefully overcome this problem.
Molecular identity and gene expression of aldosterone synthase cytochrome P450
DOE Office of Scientific and Technical Information (OSTI.GOV)
Okamoto, Mitsuhiro; Nonaka, Yasuki; Takemori, Hiroshi
11{beta}-Hydroxylase (CYP11B1) of bovine adrenal cortex produced corticosterone as well as aldosterone from 11-deoxycorticosterone in the presence of the mitochondrial P450 electron transport system. CYP11B1s of pig, sheep, and bullfrog, when expressed in COS-7 cells, also performed corticosterone and aldosterone production. Since these CYP11B1s are present in the zonae fasciculata and reticularis as well as in the zona glomerulosa, the zonal differentiation of steroid production may occur by the action of still-unidentified factor(s) on the enzyme-catalyzed successive oxygenations at C11- and C18-positions of steroid. In contrast, two cDNAs, one encoding 11{beta}-hydroxylase and the other encoding aldosterone synthase (CYP11B2), were isolatedmore » from rat, mouse, hamster, guinea pig, and human adrenals. The expression of CYP11B1 gene was regulated by cyclic AMP (cAMP)-dependent signaling, whereas that of CYP11B2 gene by calcium ion-signaling as well as cAMP-signaling. Salt-inducible protein kinase, a cAMP-induced novel protein kinase, was one of the regulators of CYP11B2 gene expression.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stegeman, J.; Miller, C.; Moore, M.
1994-12-31
Marine mammals may be important indicators of effects of contaminants that are globally distributed. Recently the authors described apparent environmental induction of hepatic CYPLA in beluga whales. Here they describe the localization and extent of CYPLA expression in organs of the pilot whale. Tissues from 18 pilot whales stranded on Cape Cod in 1990/91 were frozen in liquid N2 or fixed in formalin and embedded. Liver microsomal EROD activity were comparable to results with other cetaceans. Immunohistochemical analysis showed a periportal localization of CYPLA in liver parenchyma, and staining in the endothelium. Renal staining was strong in brush border andmore » endothelium. Testis, ovary, and spleen showed CYPLA staining only in endothelium. Adrenal zona fasciculata and zona reticularis stained more weakly than did endothelium. In lung there was mild staining of bronchiolar epithelium and strong staining of endothelium. The results indicate that active concentrations of inducer have penetrated throughout the body. CYPLA stained in dermal endothelium, indicating that analysis of skin biopsies could allow nondestructive analysis of CYPLA induction in marine mammals. CYPLA expression in these whales was surprisingly strong, suggesting the possibility of chemical effects related to CYPLA induction.« less
Thermal effects in laser-assisted embryo hatching
NASA Astrophysics Data System (ADS)
Douglas-Hamilton, Diarmaid H.; Conia, Jerome D.
2000-08-01
Diode lasers [(lambda) equals 1480 nm] are used with in-vitro fertilization [IVF] as a promoter of embryo hatching. A focused laser beam is applied in vitro to form a channel in the zona pellucida (shell) of the pre-embryo. After transfer into the uterus, the embryo hatches: it extrudes itself through the channel and implants into the uterine wall. Laser-assisted hatching can result in improving implantation and pregnancy success rates. We present examples of zone pellucida ablation using animal models. In using the laser it is vital not to damage pre-embryo cells, e.g. by overheating. In order to define safe regimes we have derived some thermal side-effects of zona pellucida removal. The temperature profile in the beam and vicinity is predicted as function of laser pulse duration and power. In a crossed-beam experiment a HeNe laser probe detects the temperature-induced change in refractive index. We find that the diode laser beam produces superheated water approaching 200 C on the beam axis. Thermal histories during and following the laser pulse are given for regions in the neighborhood of the beam. We conclude that an optimum regime exists with pulse duration
Cold laser technique for cell surgery
NASA Astrophysics Data System (ADS)
Palanker, Daniel V.; Ohad, Shoshanit; Lewis, Aaron; Laufer, Neri
1992-08-01
A new cell surgery technique has been developed to produce well-defined alterations in cells and tissues without detectable heating and/or other structural damage in the surroundings. The technique involves the use of a 193 nm argon fluoride excimer laser which is guided through a glass pipette filled with a positive air pressure. To demonstrate the method holes were drilled in the zona pellucida of mouse oocytes. The diameter of the drilled hole was determined by the pipette tip size, and its depth by an energy emitted per pulse and number of pulses. Scanning electron microscopy of the drilled mouse oocytes showed uniform, round, well circumscribed holes with sharp edges. Oocytes that had their zona pellucida drilled with this new method fertilized in vitro and developed to the blastocyst stage in a rate similar to that of control group. These results demonstrate the non-perturbing nature of this cold laser microsurgical procedure. In addition to the extension of our results for clinical in vitro fertilization purposes, such as enhancement of fertilization and embryo biopsy, there are wide ranging possible uses of our method in fundamental and applied investigations that require sub-micron accuracy in cellular alteration.
Mapping the potential beverage quality of coffee produced in the Zona da Mata, Minas Gerais, Brazil.
Silva, Samuel de Assis; de Queiroz, Daniel Marçal; Ferreira, Williams Pinto Marques; Corrêa, Paulo Cesar; Rufino, José Luis Dos Santos
2016-07-01
Detailed knowledge of coffee production systems enables optimization of crop management, harvesting and post-harvest techniques. In this study, coffee quality is mapped as a function of coffee variety, altitude and terrain aspect attributes. The work was performed in the Zona da Mata, Minas Gerais, Brazil. A large range of coffee quality grades was observed for the Red Catuai variety. For the Yellow Catuai variety, no quality grades lower than 70 were observed. Regarding the terrain aspect, samples from the southeast-facing slope (SEFS) and the northwest-facing slope (NWFS) exhibited distinct behaviors. The SEFS samples had a greater range of quality grades than did the NWFS samples. The highest grade was obtained from an NWFS point. The lowest quality values and the largest range of grades were observed at lower altitudes. The extracts from the highest-altitude samples did not produce any low-quality coffee. The production site's position and altitude are the primary variables that influenced the coffee quality. The study area has micro-regions with grades ranging from 80 to 94. These areas have the potential for producing specialty coffees. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
Rudolph, Abby E.; Gaines, Tommi L.; Lozada, Remedios; Vera, Alicia; Brouwer, Kimberly C.
2015-01-01
Respondent-driven sampling’s (RDS) widespread use and reliance on untested assumptions suggests a need for new exploratory/diagnostic tests. We assessed geographic recruitment bias and outcome-correlated recruitment among 1048 RDS-recruited people who inject drugs (Tijuana, Mexico). Surveys gathered demographics, drug/sex behaviors, activity locations, and recruiter-recruit pairs. Simulations assessed geographic and network clustering of active syphilis (RPR titers≥1:8). Gender-specific predicted probabilities were estimated using logistic regression with GEE and robust standard errors. Active syphilis prevalence was 7% (crude: men=5.7% and women=16.6%; RDS-adjusted: men=6.7% and women=7.6%). Syphilis clustered in the Zona Norte, a neighborhood known for drug and sex markets. Network simulations revealed geographic recruitment bias and non-random recruitment by syphilis status. Gender-specific prevalence estimates accounting for clustering were highest among those living/working/injecting/buying drugs in the Zona Norte and directly/indirectly connected to syphilis cases (men:15.9%, women:25.6%) and lowest among those with neither exposure (men:3.0%, women:6.1%). Future RDS analyses should assess/account for network and spatial dependencies. PMID:24969586
Characterization of oocyte retrieval cycles with empty zona pellucida.
Oride, Aki; Kanasaki, Haruhiko; Hara, Tomomi; Ohta, Hiroko; Kyo, Satoru
2018-01-01
To identify the factors that characterize cycles with empty zona pellucida (EZP). Thirty-six oocyte retrieval cycles from which EZP were collected and another 36 cycles from which no EZP was collected were compared. The patients were divided into three groups: those with no EZP collected during any cycle, those with EZP collected during all cycles, and those experiencing cycles both with and without EZP. The mean number of oocytes collected per cycle was higher in the cycles with EZP than without EZP. The fertilization rate of the collected oocytes and the rate of good embryo formation were significantly lower in the cycles with EZP. No significant difference was observed between the three groups in terms of age, number of oocytes collected, or hormone levels before and after the oocyte retrieval. The fertilization and pregnancy rates were highest in the patients with no EZP being collected during any cycle, followed by those experiencing cycles both with and without EZP, and then by those with EZP collected during all cycles. The observation of lower fertilization, poor embryo formation, and a low pregnancy rate in the patients with EZP suggests the poor quality of oocytes that were collected with EZP in the same cycle.
Rudolph, Abby E; Gaines, Tommi L; Lozada, Remedios; Vera, Alicia; Brouwer, Kimberly C
2014-12-01
Respondent-driven sampling's (RDS) widespread use and reliance on untested assumptions suggests a need for new exploratory/diagnostic tests. We assessed geographic recruitment bias and outcome-correlated recruitment among 1,048 RDS-recruited people who inject drugs (Tijuana, Mexico). Surveys gathered demographics, drug/sex behaviors, activity locations, and recruiter-recruit pairs. Simulations assessed geographic and network clustering of active syphilis (RPR titers ≥1:8). Gender-specific predicted probabilities were estimated using logistic regression with GEE and robust standard errors. Active syphilis prevalence was 7 % (crude: men = 5.7 % and women = 16.6 %; RDS-adjusted: men = 6.7 % and women = 7.6 %). Syphilis clustered in the Zona Norte, a neighborhood known for drug and sex markets. Network simulations revealed geographic recruitment bias and non-random recruitment by syphilis status. Gender-specific prevalence estimates accounting for clustering were highest among those living/working/injecting/buying drugs in the Zona Norte and directly/indirectly connected to syphilis cases (men: 15.9 %, women: 25.6 %) and lowest among those with neither exposure (men: 3.0 %, women: 6.1 %). Future RDS analyses should assess/account for network and spatial dependencies.
Intracellular activation of ovastacin mediates pre-fertilization hardening of the zona pellucida.
Körschgen, Hagen; Kuske, Michael; Karmilin, Konstantin; Yiallouros, Irene; Balbach, Melanie; Floehr, Julia; Wachten, Dagmar; Jahnen-Dechent, Willi; Stöcker, Walter
2017-09-01
How and where is pro-ovastacin activated and how does active ovastacin regulate zona pellucida hardening (ZPH) and successful fertilization? Ovastacin is partially active before exocytosis and pre-hardens the zona pellucida (ZP) before fertilization. The metalloproteinase ovastacin is stored in cortical granules, it cleaves zona pellucida protein 2 (ZP2) upon fertilization and thereby destroys the ZP sperm ligand and triggers ZPH. Female mice deficient in the extracellular circulating ovastacin-inhibitor fetuin-B are infertile due to pre-mature ZPH. We isolated oocytes from wild-type and ovastacin-deficient (Astlnull) FVB mice before and after fertilization (in vitro and in vivo) and quantified ovastacin activity and cleavage of ZP2 by immunoblot. We assessed ZPH by measuring ZP digestion time using α-chymotrypsin and by determining ZP2 cleavage. We determined cellular distribution of ovastacin by immunofluorescence using domain-specific ovastacin antibodies. Experiments were performed at least in triplicate with a minimum of 20 oocytes. Data were pre-analyzed using Shapiro-Wilk test. In case of normal distribution, significance was determined via two-sided Student's t-test, whereas in case of non-normal distribution via Mann-Whitney U-test. Metaphase II (MII) oocytes contained both inactive pro-ovastacin and activated ovastacin. Immunoblot and ZP digestion assays revealed a partial cleavage of ZP2 even before fertilization in wild-type mice. Partial cleavage coincided with germinal-vesicle breakdown and MII, despite the presence of fetuin-B protein, an endogenous ovastacin inhibitor, in the follicular and oviductal fluid. Upon exocytosis, part of the C-terminal domain of ovastacin remained attached to the plasmalemma, while the N-terminal active ovastacin domain was secreted. This finding may resolve previously conflicting data showing that ovastacin acts both as an oolemmal receptor termed SAS1B (sperm acrosomal SLLP1 binding protein; SLLP, sperm lysozyme like protein) and a secreted protease mediating ZP2 cleavage. For this study, only oocytes isolated from wild-type and ovastacin-deficient FVB mice were investigated. Some experiments involved oocyte activation by the Ca2+ ionophore A23187 to trigger ZPH. This study provides a detailed spatial and temporal view of pre-mature cleavage of ZP2 by ovastacin, which is known to adversely affect IVF rate in mice and humans. None. This work was supported by the Center of Natural Sciences and Medicine and by a start-up grant of the Johannes Gutenberg University Mainz to W.S., and by a grant from Deutsche Forschungsgemeinschaft and by the START program of the Medical Faculty of RWTH Aachen University to J.F. and W.J.D. There are no competing interests to declare. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com
NASA Astrophysics Data System (ADS)
Gaus, Irina
Pesticides are a potential threat to the quality of extracted groundwater when the water-supply area is used for agricultural activities. This problem is discussed for the water-supply area of Sint-Jansteen, The Netherlands, where measured pesticide concentrations in the extracted water regularly exceed EU limits (0.1μg/L). Groundwater samples taken from the aquifer within the water-supply area show low contamination, but samples taken from the extracted water occasionally contain pesticides, making the water inadequate for drinking-water purposes. The more intense contamination of the extracted water is caused by the change in the natural groundwater flow pattern near the extraction wells. In this area, pesticide use cannot be avoided easily, and an approach is given to differentiate pesticide use in the area according to expected travel time toward the wells and the chemical characteristics of the pesticides. A groundwater flow model for the area is developed and the effects of groundwater extraction on the natural flow pattern are evaluated. Using particle tracking, the travel-time zones are determined. Combining these results and the degradation behavior of certain pesticides led to an optimal scheme to integrate agricultural activities and groundwater extraction in the area. This is illustrated for five different types of pesticides (atrazine, simazine, bentazone, MCPA, and mecoprop). Résumé Les pesticides sont une menace potentielle pour la qualité de l'eau souterraine prélevée lorsque la zone de captage est soumise à des activités agricoles. Ce problème est discuté dans le cas de la zone de captage de Sint-Jansteen (Pays-Bas), où les concentrations mesurées en pesticides dans les eaux pompées dépassent régulièrement les normes européennes (0,1μg/L). Les échantillons d'eau souterraine prélevés dans l'aquifère dans la zone de captage montrent une faible contamination, mais les échantillons d'eau pompée contiennent occasionnellement des pesticides, ce qui rend l'eau impropre à la consommation. La contamination plus importante de l'eau pompée est provoquée par la modification des directions d'écoulement souterrain naturel au voisinage des puits de pompage. Dans cette région, l'usage des pesticides ne peut pas être évité facilement; c'est pourquoi une approche est développée pour différencier les usages de pesticides dans ce secteur en fonction des temps de parcours prévus en direction des puits et des caractéristiques chimiques des pesticides. Un modèle d'écoulement des eaux souterraines pour cette région a été développé et les effets des pompages sur les directions d'écoulement naturel ont étéévalués. Les zones de temps de parcours ont été déterminées au moyen de la méthode du suivi de particules (particle tracking). La combinaison de ces résultats avec le comportement de certains pesticides au cours de leur dégradation conduit à un schéma optimisé conciliant les activités agricoles et les prélèvements d'eaux souterraines dans cette région. Cette question est abordée pour cinq types de pesticides (atrazine, simazine, bentazone, MCPA et mecoprop). Resumen Los pesticidas son una amenaza para la calidad de las aguas subterráneas cuando el área de suministro se encuentra en una zona agrícola. Un ejemplo tiene lugar en la zona de Sint-Jansteen, Holanda, donde mientras que las muestras de agua subterránea tomadas directamente del acuífero tienen un bajo nivel de contaminación por pesticidas, las muestras tomadas del agua extraída exceden con regularidad los límites de la UE (0.1μg/l), lo que hace que el agua sea no potable. Esta diferencia está causada por las variaciones respecto al régimen de flujo natural a consecuencia de las propias extracciones. En esta zona el uso de pesticidas es difícilmente evitable, por lo que se está desarrollando un método para diferenciar la posibilidad de uso de pesticidas en función de las características químicas de los pesticidas y de su tiempo de tránsito esperado hasta los pozos de abastecimiento. Se está desarrollando un modelo matemático para evaluar los efectos de las extracciones sobre el flujo subterráneo natural. Usando el método de seguimiento de partículas se calculan los tiempos de tránsito, y combinando estos resultados con la biodegradación potencial de los pesticidas se diseña un esquema óptimo para la integración de actividades agrícolas y de uso de boca en el área. Esta metodología se muestra para distintos tipos de pesticidas.
Estimation of groundwater recharge using the chloride mass-balance method, Pingtung Plain, Taiwan
NASA Astrophysics Data System (ADS)
Ting, Cheh-Shyh; Kerh, Tienfuan; Liao, Chiu-Jung
Due to rapid economic growth in the Pingtung Plain of Taiwan, the use of groundwater resources has changed dramatically. Over-pumping of the groundwater reservoir, which lowers hydraulic heads in the aquifers, is not only affecting the coastal area negatively but has serious consequences for agriculture throughout the plain. In order to determine the safe yield of the aquifer underlying the plain, a reliable estimate of groundwater recharge is desirable. In the present study, for the first time, the chloride mass-balance method is adopted to estimate groundwater recharge in the plain. Four sites in the central part were chosen to facilitate the estimations using the ion-chromatograph and Thiessen polygon-weighting methods. Based on the measured and calculated results, in all sites, including the mountain and river boundaries, recharge to the groundwater is probably 15% of the annual rainfall, excluding recharge from additional irrigation water. This information can improve the accuracy of future groundwater-simulation and management models in the plain. Résumé Du fait de la croissance économique rapide de la plaine de Pingtung à Taiwan, l'utilisation des ressources en eau souterraine s'est considérablement modifié. La surexploitation des aquifères, qui a abaissé le niveau des nappes, n'affecte pas seulement la région côtière, mais a de sérieuses répercutions sur l'agriculture dans toute la plaine. Afin de déterminer les ressources renouvelables de l'aquifère sous la plaine, une estimation précise de la recharge de la nappe est nécessaire. Dans cette étude, le taux de recharge de la nappe a d'abord été estimé au moyen d'un bilan de matière de chlorure. Quatre sites de la partie centrale ont été sélectionnés pour réaliser ces estimations, à l'aide d'un chromatographe ionique et de la méthode des polygones de Thiessen. A partir des résultats mesurés et calculés, à chaque site, et en prenant comme limites les montagnes et les rivières, la recharge de la nappe a étéévaluée à environ 15% des précipitations annuelles, sans tenir compte de la recharge par le retour d'irrigation. Ce résultat doit permettre de tester la précision de la simulation de nappe qui va être faite, ainsi que les modèles de gestion de la plaine. Resumen Debido al rápido crecimiento económico de la zona de la Llanura de Pingtung, Taiwan, el uso de los recursos de agua subterránea ha cambiado radicalmente. La sobreexplotación, con el consiguiente descenso de los niveles piezométricos en los acuíferos, no sólo afecta las áreas costeras, sino que está teniendo consecuencias importantes para la agricultura de la zona. Para determinar la extracción sostenible en el acuífero, es deseable una buena estimación de la recarga. En este estudio se adopta por primera vez el método de balance de cloruros para estimar la recarga en el llano. Se seleccionaron cuatro puntos en la parte central para facilitar las estimaciones mediante los métodos de cromatógrafo iónico y de polígonos de Thiessen. A partir de los resultados medidos y calculados en toda la zona, e incluyendo los contornos de montañas y ríos, la recarga subterránea es de cerca del 15% de la precipitación anual, excluyendo la recarga que se produce por riego adicional. Este dato permitirá mejorar la precisión de los modelos de simulación de flujo y de gestión que se realizarán en el futuro.
[Reconstrucción ósea de defectos craneales secundarios a traumatismo con implantes personalizados].
Cienfuegos, Ricardo; Fernández, Gerardo; Cruz, Aída; Sierra, Eduardo
2018-01-01
Los defectos craneales secundarios a traumatismos son frecuentes. Por lo común se reparan de forma secundaria por sintomatología como el síndrome del paciente trepanado, por protección cerebral y por el aspecto cosmético. Históricamente se han utilizado diversos materiales para la reconstrucción. Se presentan cinco casos de pacientes reconstruidos con implantes personalizados de polieteretercetona (PEEK) o polimetilmetacrilato poroso (PMMA). Las localizaciones afectaron el frontal, el borde orbitario superior y el techo orbitario en cuatro casos, y la porción lateral del frontal, la zona temporoparietal y el borde del occipital en un caso. La reconstrucción en cuatro pacientes fue entre 6 y 12 meses después de la lesión, y en un caso después de 25 años. En dos casos se requirió expansión tisular antes de colocar el implante. Cuatro pacientes evolucionaron favorablemente, con mejoría de los síntomas neurológicos, forma y contorno adecuados, así como un proceso de cicatrización adecuada de los colgajos de piel cabelluda. Un paciente presentó infección por Staphylococcus aureus, atribuida a la presencia de un mucocele y una fístula de la vía aérea a la cavidad craneal, lo que hizo necesario retirar el implante. Los implantes personalizados son un recurso útil para defectos óseos craneales. Brindan resultados satisfactorios desde el punto de vista funcional y cosmético. Deben tomarse precauciones respecto al tratamiento de las lesiones que afecten el seno frontal, para evitar la comunicación entre la vía aérea y la cavidad craneal. Cranial defects due to trauma are frequent. They are usually repaired in a secondary fashion due to features such as syndrome of the trephined, for brain protection and for cosmetic purposes. Historically, various materials have been used for reconstruction. Five cases of patients reconstructed with customized polyetheretherketone (PEEK) o polymethyl methacrylate (PMMA) implants are presented. Defects involved the frontal bone, superior orbital rim and orbital roof in four cases, and the lateral area of the frontal bone, the temporoparietal area and the border of the occipital bone in one. In four patients, reconstruction took place between 6 and 12 months after the injury; in one patient, after 25 years. Two cases required tissue expansion before placing the implant. Four patients evolved favorably, with improvement in neurologic symptoms and adequate shape and contour, plus adequate healing of the scalp flaps. One patient had an infection due to Staphylococcus aureus, attributed to a mucocele and fistula between the airway and the cranial cavity, leading to removal of the implant. Customized implants are a useful resource for cranial defects. They offer satisfactory results, both functional and cosmetic. Precautions should be taken in treating injuries that involve the frontal sinus, to ensure there is no communication between the airway and the cranial cavity. Copyright: © 2018 SecretarÍa de Salud.
40-years of fires in a touristic area from South of Spain.
NASA Astrophysics Data System (ADS)
Martínez-Murillo, Juan F.; Aranda-Gómez, Francisco; Damián Ruiz-Sinoga, José
2014-05-01
Costa del Sol in the Province of Malaga is one of the major touristic region in Spain. Its develop started in the 1960s of the XXth century at the same time as other regions in Mediterranean Europe. Since then, this area has become a holiday touristic centre for different countries and regions from Europe (United Kingdom, Escandinavia, Germany, Netherlands, Russia, etc.). Likewise, Costa del Sol has been characterised by a constant grow of the residence tourism rendering in an extreme increment of urban areas, especially in those municipalities located in the coast. This expansión of urban áreas was carried out against rural and natural vegetated areas. The region is characterised by very montanious topography, predominant impermeable rocks (shales, schists and peridotites) and abundant rainfalls from October to May, especially, in the western area (where a climatic gradient is observed from humid to dry conditions). All of these features, joined a very spread and intense occupation by urban, infrastructures and touristic land uses, renders in a very high vulnerability to fires and their consequences. As fire removes vegetation cover and accelerate water erosion, local relief and climatic conditions induce to extreme high risk of soil loss and floodings. During the last 40 years, in the study area, the number of fires increased as weell as the affected area, following the similar trend for the rest of Spain and other Mediterranean countries. This situation increases the exposition to fire risk for more than one-million of people, which become at least two-millions during the summer months when fire conditions are expected.
Effects of Vitrification on Outcomes of In Vivo-Mature, In Vitro-Mature and Immature Human Oocytes.
Song, Wen-Yan; Peng, Zhao-Feng; Chen, Xue-Mei; Jin, Hai-Xia; Yao, Gui-Dong; Shi, Sen-Lin; Yang, Hong-Yi; Zhang, Xiang-Yang; Sun, Ying-Pu
2016-01-01
To observe the effects of vitrification on spindle, zona pellucida, embryonic aneuploidy and DNA injury in in vivo-maruted, in vitro-mature and immature human oocytes. Between January 2009 and February 2015, 223 immature oocytes from 450 infertile patients, and 31 in vivo-mature oocytes from 3 infertile couples were collected. Of the 223 immature oocytes, 113 were used for in vitro culture before vitrification. Some oocytes were randomly divided into in vivo-mature group (group A, n = 15), in vitro-mature group (group B, n = 88) and immature group (group C, n = 85), and then the oocytes with spindle in these three groups after freezing-thawing were selected to use for Polscope imaging, embryonic aneuploidy screening and embryo development evaluation. Other oocytes were randomly divided into group A (n = 16), group B (n = 25) and group C (n = 25) for detecting DNA injury. After thawing, spindle occurrence rate, spindle Retardance value, and cleavage rate were significantly higher in groups A and B than in group C (all P < 0.05), but there were no statistical differences in fertility rate, high-quality embryo rate, blastulation rate and aneuploidy rate amongst the three groups (all P > 0.05). Zona pellucida density (ZPD) was significantly lower in group A than in groups B and C both before and after vitrification (all P < 0.05). ZPD was significantly higher after thawing than before vitrification (all P < 0.05), but zona pellucida thickness (ZPT) was not significantly changed in all the three groups (all P > 0.05). Rate of comet cells was significantly lower in group A than in groups B and C (all P < 0.01). Comet tail was significantly longer in group C than in groups B and A (all P < 0.05). In vivo- and in vitro-mature human oocytes are more suitable to vitrification than immature human oocytes. Spindle Retardance value has more predictive value for embryonic development potential than ZPD and ZPT. © 2016 The Author(s) Published by S. Karger AG, Basel.
Gibb, Z; Butler, T J; Morris, L H A; Maxwell, W M C; Grupen, C G
2013-04-01
Excessive reactive oxygen species generation during sex sorting and cryopreservation of stallion sperm leads to DNA fragmentation, lipid peroxidation, and motility loss. In this study we investigated whether antioxidant supplementation during sex sorting and cryopreservation could ameliorate the effects of reactive oxygen species on stallion sperm. In experiment 1, the postthaw characteristics of stallion sperm (N = 9) cryopreserved in the presence or absence of catalase (200 U/mL), cysteine (0.2 mg/mL), or quercetin (0.15 mM) was examined. Motility and acrosome integrity were assessed at 0, 1, and 3 hours after thawing. The sperm chromatin structure assay (SCSA; detectable DNA fragmentation index [DFI], mean DFI, and DFI) was used to assess DNA integrity immediately after thawing. Quercetin increased the total postthaw motility (25.3% vs. 20.9%; P < 0.05), but there was no beneficial effect of catalase or cysteine. Based on these results, the effect of quercetin during cryopreservation on the postthaw zona binding ability of sperm was assessed using a heterologous (bovine) zona binding assay. Quercetin increased the number of sperm bound per oocyte (13.6 vs. 9.2; P < 0.05) compared with the control. In experiment 2, the effect of quercetin (0.15 mM) in the media used during semen storage and transport, Hoechst 33342 staining and cryopreservation of stallion sperm (N = 9) was investigated. Motility, acrosome integrity, and viability were assessed at 0, 1, and 3 hours after thawing and SCSA was performed at 0 hours after thawing. Quercetin supplementation during sex sorting and cryopreservation improved DNA integrity (SCSA; detectable DFI of 54.9% vs. 74.6%, P < 0.05; mean DFI of 270.2 vs. 288.1, P < 0.05; and DFI of 26.3% vs. 28.5%, P < 0.05) compared with control sex-sorted sperm. There was no beneficial effect of quercetin on the motility, acrosome integrity, or viability of sex-sorted sperm. In conclusion, quercetin significantly improved the motility and zona binding ability of cryopreserved stallion sperm, and reduced DNA fragmentation in sex-sorted, cryopreserved stallion sperm. Copyright © 2013 Elsevier Inc. All rights reserved.
Assessment of water resources potential of Ceará state (Brazil)
NASA Astrophysics Data System (ADS)
Araujo, Angelo; Pereira, Diamantino; Pereira, Paulo
2016-04-01
A methodological approach and results on water resources assessment in large areas are described with the case study of Ceará State (148,016 km2, northeast Brazil), where the scarceness of water resources is one of the main challenges in territorial planning and development. This work deals with the quantification and the mapping of water resources potential, being part of methodological approaches applied to the quantification of hydric diversity and geodiversity. Water resources potential is here considered as the sum of the hydric elements rainfall, groundwater specific discharge, water reservoirs, and river hierarchy. The assessment was based in a territorial organization by drainage sub-basins and in vector maps generated and treated with GIS software. Rainfall, groundwater specific discharge and hydrographical data were obtained in official institutions and allowed the construction of the annual mean rainfall map for a forty year period (1974-2014), the annual mean groundwater specific discharge map for a thirty-four year period, and the river and drainage basin hierarchy maps. These delivered rainfall, groundwater specific discharge, water reservoirs and river hierarchy partial indices expressed on quantitative maps with normalized values distributed by level 3 drainage basins. The sum of the partial indices originated the quantitative map of water resources potential index and by the Gaussian interpolation of this quantitative data a map of hydric diversity in Ceará state was created. Therefore, the water resources potential index is higher in 4 regions of the state (Noroeste Cearense, Zona Metropolitana de Fortaleza e da Zona Norte, Vale do Jaguaribe and Zonas Centro-sul e Sul Cearense). The index is low or very low in the whole region of Sertões Cearenses, confirming the important role of climatic features in hydrological diversity. Water resources management must consider technical tools for water resources assessment, in the line of other methods for quantitative assessment of natural features either biotic or abiotic. These results quantify water resources and their distribution in a large region with important climatic differences. They constitute a basis for the knowledge of regional issues concerning water needs, flood and droughts events and even engineering solutions for water resources management.
Factors affecting the electrofusion of mouse and ferret oocytes with ferret somatic cells.
Li, Ziyi; Sun, Xingshen; Chen, Juan; Leno, Gregory H; Engelhardt, John F
2005-09-01
The domestic ferret, Mustela putorius furos, holds great promise as a genetic model for human lung disease, provided that key technologies for somatic cell nuclear transfer (SCNT) are developed. In this report, we extend our understanding of SCNT in this species by defining conditions for efficient cell fusion by electrical pulse. Two experimental systems were employed in this study. First, in vivo-matured mouse oocytes and ferret somatic cells were used to establish general parameters for fusion. One fibroblast, or cumulus cell, was agglutinated to nucleate, zona pellucida-free, mouse oocytes, and subjected to an electrical pulse. Similar electrical pulse conditions were also tested with 1 or 2 somatic cells inserted into the perivitelline space (PVS) of intact mouse oocytes. The fusion rate for a single fibroblast with a zona-free oocyte was 80.2%, significantly higher (P < 0.05) than that observed for 1, or 2, fibroblasts placed in the PVS (52.0% and 63.8%, respectively). The fusion rate (44.1%) following insertion of two cumulus cells was significantly higher (P < 0.05) than that following insertion of one cumulus cell (25.1%). Second, in vitro-matured ferret oocytes were enucleated, and one to three fibroblasts or cumulus cells were inserted into the PVS. Zona pellucida-free ferret oocytes were fragile and excluded from the study. The fusion rates with two or three fibroblasts were 71.4% and 76.8%, respectively; significantly higher (P < 0.05) than that for one fibroblast (48.6%). This cell number-dependent difference in fusion efficiency was also observed with cumulus cells. Fusion-derived (ferret-ferret) NT embryos cleaved, formed blastocysts in vitro, and underwent early-stage fetal development following embryo transfer. The rate of development was cell type-independent, in contrast to the cell type-dependent differences observed in fusion efficiency. In conclusion, fibroblasts fused more efficiently than cumulus cells and the efficiency of single cell fusions was improved when two or more cells were inserted into the PVS. These studies define conditions for efficient cell fusion with ferret oocytes and should facilitate SCNT and the development of genetically defined animal models in this species.
Disinfection of Contaminated Water by Using Solar Irradiation
Caslake, Laurie F.; Connolly, Daniel J.; Menon, Vilas; Duncanson, Catriona M.; Rojas, Ricardo; Tavakoli, Javad
2004-01-01
Contaminated water causes an estimated 6 to 60 billion cases of gastrointestinal illness annually. The majority of these cases occur in rural areas of developing nations where the water supply remains polluted and adequate sanitation is unavailable. A portable, low-cost, and low-maintenance solar unit to disinfect unpotable water has been designed and tested. The solar disinfection unit was tested with both river water and partially processed water from two wastewater treatment plants. In less than 30 min in midday sunlight, the unit eradicated more than 4 log10 U (99.99%) of bacteria contained in highly contaminated water samples. The solar disinfection unit has been field tested by Centro Panamericano de Ingenieria Sanitaria y Ciencias del Ambiente in Lima, Peru. At moderate light intensity, the solar disinfection unit was capable of reducing the bacterial load in a controlled contaminated water sample by 4 log10 U and disinfected approximately 1 liter of water in 30 min. PMID:14766599
Cecere, M. C.; Gürtler, R. E.; Chuit, R.; Cohen, J. E.
1998-01-01
Reported are the environmental and demographic risk factors associated with the domestic infestation and density of Triatoma infestans in three heavily infested rural villages in Santiago del Estero Province, Argentina. In a one-factor unadjusted analysis, the number of T. infestans captured per person-hour was associated significantly and negatively with the use of domestic insecticides by householders, type of thatch used in the roofs and the age of the house; and positively with the following: degree of cracking of the indoor walls and presence of hens nesting indoors. In one model, using multiple linear regression and a backward stepwise elimination procedure, most of the variation in the overall abundance of T. infestans was explained by insecticide use and the presence of hens nesting indoors; in another model using the same procedure it was explained by insecticide use, bug density in 1988 and previous spraying with deltamethrin in 1985. Variations in bug density per capture stratum (household goods, beds, walls and roof) were explained by the bug density in other strata and by one or two of the following risk factors: hens nesting indoors, type of roof, presence of cracks in the walls and number of people living in the house. Bug density might be locally controlled by the availability of refuges in the roofs and walls, by the presence of hens nesting indoors and by the use of domestic insecticides. Certain local materials, such as a grass known as simbol, could be successfully used in rural housing improvement programmes aimed at reducing the availability of refuges for insects in the roof. PMID:9803588
Cecere, M C; Gürtler, R E; Chuit, R; Cohen, J E
1998-01-01
Reported are the environmental and demographic risk factors associated with the domestic infestation and density of Triatoma infestans in three heavily infested rural villages in Santiago del Estero Province, Argentina. In a one-factor unadjusted analysis, the number of T. infestans captured per person-hour was associated significantly and negatively with the use of domestic insecticides by householders, type of thatch used in the roofs and the age of the house; and positively with the following: degree of cracking of the indoor walls and presence of hens nesting indoors. In one model, using multiple linear regression and a backward stepwise elimination procedure, most of the variation in the overall abundance of T. infestans was explained by insecticide use and the presence of hens nesting indoors; in another model using the same procedure it was explained by insecticide use, bug density in 1988 and previous spraying with deltamethrin in 1985. Variations in bug density per capture stratum (household goods, beds, walls and roof) were explained by the bug density in other strata and by one or two of the following risk factors: hens nesting indoors, type of roof, presence of cracks in the walls and number of people living in the house. Bug density might be locally controlled by the availability of refuges in the roofs and walls, by the presence of hens nesting indoors and by the use of domestic insecticides. Certain local materials, such as a grass known as simbol, could be successfully used in rural housing improvement programmes aimed at reducing the availability of refuges for insects in the roof.
NASA Astrophysics Data System (ADS)
Sanford, Ward E.; Plummer, L. Niel; McAda, Douglas P.; Bexfield, Laura M.; Anderholm, Scott K.
The calibration of a groundwater model with the aid of hydrochemical data has demonstrated that low recharge rates in the Middle Rio Grande Basin may be responsible for a groundwater trough in the center of the basin and for a substantial amount of Rio Grande water in the regional flow system. Earlier models of the basin had difficulty reproducing these features without any hydrochemical data to constrain the rates and distribution of recharge. The objective of this study was to use the large quantity of available hydrochemical data to help calibrate the model parameters, including the recharge rates. The model was constructed using the US Geological Survey's software MODFLOW, MODPATH, and UCODE, and calibrated using 14C activities and the positions of certain flow zones defined by the hydrochemical data. Parameter estimation was performed using a combination of nonlinear regression techniques and a manual search for the minimum difference between field and simulated observations. The calibrated recharge values were substantially smaller than those used in previous models. Results from a 30,000-year transient simulation suggest that recharge was at a maximum about 20,000 years ago and at a minimum about 10,000 years ago. Le calibrage d'un modèle hydrogéologique avec l'aide de données hydrochimiques a démontré que la recharge relativement faible dans le Grand Bassin du Middle Rio est vraisemblablement responsable d'une dépression des eaux souterraines dans le centre du bassin et de la présence d'une quantité substantielle d'eau du Rio Grande dans l'aquifère du Groupe de Santa Fe. Les modèles antérieurs avaient des difficultés à reproduire ses conclusions sans l'aide de données hydrochimiques pour contraindre les taux et la distribution de la recharge. L'objectif de cette étude était d'utiliser une grande quantité de données hydrochimiques permettant de calibrer les paramètres du modèle, et notamment les taux de recharge. Le modèle a été construit avec les logiciels MODFLOW, MODPATH et UCODE, et calibré en utilisant les concentrations en 14C et la position de certaines zones définies par les données hydrochimiques. L'estimation de certains paramètres a été réalisée en utilisant une combinaison de techniques de régression non linéaire et une méthode de recherche exhaustive (Brute Force Search) de l'erreur minimum entre les résultats des observations et les simulations. Les valeurs de la recharge calibrée sont substantiellement plus basses que celles estimées dans les modèles antérieurs. Les résultats d'une simulation en régime transitoire sur 30.000 ans suggèrent que la recharge au maximum de la dernière glaciation (last glacial maximum, LGM) était 10 fois supérieure au taux actuel, mais que la recharge qui a suivit la LGM était plus bas que la recharge actuelle. La calibración de un modelo de aguas subterráneas con el apoyo de datos hidroquímicos ha demostrado que la recarga relativamente baja en la cuenca media del Río Grande es probablemente responsable de una depresión de aguas subterráneas en el centro de la cuenca y de la presencia de una cantidad considerable de agua del Río Grande en el acuífero del Grupo Santa Fe. Los modelos propuestos con anterioridad para la cuenca tenían dificultades para reproducir estas características ya que no tenían datos hidroquímicos que permitieran delimitar los ritmos y distribución de recarga. El objetivo del presente estudio consistió en utilizar una gran cantidad de datos hidroquímicos disponibles para ayudar a calibrar los parámetros del modelo, incluyendo los ritmos de recarga. El modelo se construyó utilizando los modelos MODFLOW, MODPATH, y UCODE del USGS, mientras que la calibración se realizó en base a concentraciones de 14C y a la posición de ciertas zonas definidas con los datos hidroquímicos. La estimación de parámetros se realizó en base a una combinación de técnicas de regresiones no lineares y a una búsqueda a viva fuerza del error mínimo entre los datos observados y los simulados. Los valores de recarga calibrados fueron significativamente más bajos que los estimados en los modelos anteriores. Los resultados de una simulación transitoria de 30,000 años sugieren que la recarga durante la última glacial máxima (LGM) fue diez veces el ritmo moderno, pero que la recarga que ocurrió inmediatamente después de la LGM fue más baja que el ritmo moderno.
NASA Astrophysics Data System (ADS)
Lin, Nian-Feng; Tang, Jie; Han, Feng-Xiang
2001-02-01
Since ancient times, water resources, mainly from melting snow in the high mountains, have nourished a large area of an oasis in the Kashi Plain in the western Terim Basin, China. In the last half-century, however, the rapid growth of population and the overexploitation of water, soil, and biological resources have led to drought, salinization, and desertification in the area, and consequently have hindered the development of sustainable agriculture. In this study, groundwater reservoirs with sustainable water supplies equivalent to 44.65×108 m3/year were identified, which has made it possible to implement several projects in the area to improve the ecological and agricultural environment. Three strategies are proposed for the integrated development and management of both surface-water and groundwater resources in the area. Résumé. Depuis des temps anciens, les ressources en eaux, provenant surtout de la fonte des neiges en montagne, ont alimenté une large part d'une oasis de la plaine de Kashi, dans le bassin occidental de Terim (Chine). Au cours des derniers cinquante ans, toutefois, l'accroissement rapide de la population et la surexploitation de l'eau, des sols et des ressources biologiques ont provoqué la sécheresse, la salinisation et la désertification de la région cela a eu pour conséquence d'entraver le développement d'une agriculture durable. Cette étude identifie les réserves en eau souterraine, susceptibles de fournir durablement 44,65×108 m3/an, ce qui a permis de réaliser plusieurs projets dans cette région pour améliorer l'environnement écologique et agricole. Trois stratégies sont proposées pour le développement intégré et la gestion simultanée des ressources en eau de surface et en eau souterraine de cette région. Resumen. Los recursos hídricos, procedentes fundamentalmente del deshielo en alta montaña, han nutrido desde tiempo inmemorial una gran área de un oasis situado en las llanuras de Kashi, en la cuenca occidental de Terim (China). Sin embargo, en la última mitad de siglo, el rápido aumento de población y la sobreexplotación de los recursos hídricos, pedológicos y biológicos han producido la sequía, salinización y desertificación en la zona, y, por consiguiente, han obstaculizado el desarrollo de una agricultura sostenible. En este estudio, se identificaron reservorios de agua subterránea con unos recursos equivalentes a 44,65×108 m3/a, hecho que ha permitido establecer varios proyectos en el área para mejorar el medio ambiente ecológico y agrícola. Se proponen tres estrategias para el desarrollo integrado y la gestión en la zona, tanto de los recursos superficiales como de los subterráneos.
El Estado de los Bosques de Puerto Rico, 2003
Thomas J. Brandeis; Eileen H. Helmer; Sonja N. Oswalt
2003-01-01
La cobertura forestal de Puerto Rico sigue aumentando y ahora asciende a un 57 por ciento en la isla de Puerto Rico, 85 por ciento en Vieques y 88 por ciento en Culebra. Los bosques subtropicales secos ocupan 50 346 ha, 6832 ha, 2591 ha y 6217 ha en las islas de Puerto Rico, Vieques, Culebra y Mona, respectivamente. El bosque subtropical húmedo, la zona de vida...
Gardner, R L; Davies, T J
2006-02-01
Preliminary observations revealed that advanced zygotes of the PO strain mouse are often bilaterally symmetrical, and suggested that both the plane of first cleavage and features of the blastocyst bear a consistent relationship to the zygote's bilateral plane. Spaced oil drops were injected into the zona pellucida to delineate the bilateral plane in pronuclear zygotes, and a distinct cluster of drops then placed over the second polar body. Such non-invasive marking was combined with gelation of the perivitelline space to prevent rotation of the zygotes within the zona pellucida. Nearly two-thirds of advanced pronuclear stage zygotes were bilaterally symmetrical and, regardless of whether first cleavage was meridional, it was almost invariably orthogonal to the bilateral plane. Moreover, both the axis of polarity and bilateral plane of the blastocyst bore a consistent relationship to the zygote's bilateral plane. Haploid parthenotes also exhibited bilateral symmetry, although in the absence of fertilization, first cleavage was less consistently orthogonal to the bilateral plane. Bilateral symmetry may be an intrinsic property of the oocyte that is induced by its activation and, from the reproducible way it maps on both the 2-cell conceptus and blastocyst, seems to play a role in early patterning.
Khalilian, Morteza; Navidbakhsh, Mahdi; Valojerdi, Mojtaba Rezazadeh; Chizari, Mahmoud; Yazdi, Poopak Eftekhari
2010-01-01
The zona pellucida (ZP) is the spherical layer that surrounds the mammalian oocyte. The physical hardness of this layer plays a crucial role in fertilization and is largely unknown because of the lack of appropriate measuring and modelling methods. The aim of this study is to measure the biomechanical properties of the ZP of human/mouse ovum and to test the hypothesis that Young's modulus of the ZP varies with fertilization. Young's moduli of ZP are determined before and after fertilization by using the micropipette aspiration technique, coupled with theoretical models of the oocyte as an elastic incompressible half-space (half-space model), an elastic compressible bilayer (layered model) or an elastic compressible shell (shell model). Comparison of the models shows that incorporation of the layered geometry of the ovum and the compressibility of the ZP in the layered and shell models may provide a means of more accurately characterizing ZP elasticity. Evaluation of results shows that although the results of the models are different, all confirm that the hardening of ZP will increase following fertilization. As can be seen, different choices of models and experimental parameters can affect the interpretation of experimental data and lead to differing mechanical properties. PMID:19828504
Is vitronectin the velcro that binds the gametes together?
Fusi, F M; Bernocchi, N; Ferrari, A; Bronson, R A
1996-11-01
Evidence has been presented that the adhesion of human spermatozoa to the oolemma is mediated by integrins recognizing the Arg-Gly-Asp sequence (RGD). Fibronectin and vitronectin, glycoproteins that contain functional RGD sequences, are both present on human spermatozoa, and integrins that recognize these ligands have been detected on spermatozoa and eggs. In this work, we studied the effects of oligopeptides specifically designed to block fibronectin or vitronectin receptors on the interaction of human spermatozoa with zona-free hamster oocytes. GRGDdSP, a peptide blocking cell attachment to fibronectin, was without effect, while GdRGDSP, which blocks both fibronectin and vitronectin receptors, significantly inhibited the binding of human spermatozoa to the oolemma of zona-free hamster eggs, in a concentration-dependent manner, over a range 1-100 microM. As these experiments suggested that a vitronectin receptor plays a role in sperm-oolemmal adhesion, we performed a series of experiments studying the effects of exogenous vitronectin, when added to spermatozoa and oocytes, on gamete interactions. Sperm-oolemmal adherence, as well as sperm aggregation, was promoted by vitronectin, over range of 2.2 nM to 1 microM, but only in the presence of calcium ions. We propose that vitronectin released during the sperm acrosome reaction is recognized by both gametes and plays a role in their adhesion.
Cysteine protects rabbit spermatozoa against reactive oxygen species-induced damages
Fan, Xiaoteng; Pan, Yang; Lv, Shan; Pan, Chuanying; Lei, Anmin
2017-01-01
The process of cryopreservation results in over-production of reactive oxygen species, which is extremely detrimental to spermatozoa. The aim of this study was to investigate whether addition of cysteine to freezing extender would facilitate the cryosurvival of rabbit spermatozoa, and if so, how cysteine protects spermatozoa from cryodamages. Freshly ejaculated semen was diluted with Tris-citrate-glucose extender supplemented with different concentrations of cysteine. The motility, intact acrosomes, membrane integrity, mitochondrial potentials, 8-hydroxyguanosine level and sperm-zona pellucida binding capacity were examined. Furthermore, glutathione peroxidase (GPx) activity, glutathione content (GSH), and level of reactive oxygen species (ROS) and hydrogen peroxide of spermatozoa were analyzed. The values of motility, intact acrosomes, membrane integrity, mitochondrial potentials and sperm-zona pellucida binding capacity of the frozen-thawed spermatozoa in the treatment of cysteine were significantly higher than those of the control. Addition of cysteine to extenders improved the GPx activity and GSH content of spermatozoa, while lowered the ROS, DNA oxidative alterations and lipid peroxidation level, which makes spermatozoa avoid ROS to attack DNA, the plasma membrane and mitochondria. In conclusion, cysteine protects spermatozoa against ROS-induced damages during cryopreservation and post-thaw incubation. Addition of cysteine is recommended to facilitate the improvement of semen preservation for the rabbit breeding industry. PMID:28700739
FLB1, a human protein of epididymal origin that is involved in the sperm-oocyte recognition process.
Boué, F; Duquenne, C; Lassalle, B; Lefèvre, A; Finaz, C
1995-02-01
CA6 antibody was selected out of a monoclonal antibody library raised against human sperm proteins primarily for its ability to recognize an epididymal antigen and to modify sperm adhesion to zona-free hamster oocytes. In the present study, CA6 was shown to decrease sperm binding to zona-free hamster and human oocytes by 40-92% and 38-48%, respectively. The corresponding protein, which was referred to as FLB1, was found to be secreted by the epididymis and to bind specifically to a human, macaque, and rodent subacrosomal sperm region. Western blotting revealed a molecular mass of 94 kDa in human epididymal extracts and of 100 kDa in human, macaque, mouse, rat, and hamster sperm, suggesting further modifications after its binding to sperm. An equivalent protein was not observed in human liver, ovary, testis, plasma, or epidermis. Two-dimensional electrophoresis showed that FLB1 is formed of two subunits with the same 47-kDa molecular mass and slightly different pI (5.8, 5.9). Microsequencing of the protein revealed a partial homology with human cytokeratins 1 and 10. These results suggest that FLB1 is an epididymis-specific cytokeratin-like protein that is involved in the sperm-oocyte recognition process.
Swallowing Quality of Life After Zona Incerta Deep Brain Stimulation.
Sundstedt, Stina; Nordh, Erik; Linder, Jan; Hedström, Johanna; Finizia, Caterina; Olofsson, Katarina
2017-02-01
The management of Parkinson's disease (PD) has been improved, but management of signs like swallowing problems is still challenging. Deep brain stimulation (DBS) alleviates the cardinal motor symptoms and improves quality of life, but its effect on swallowing is not fully explored. The purpose of this study was to examine self-reported swallowing-specific quality of life before and after caudal zona incerta DBS (cZI DBS) in comparison with a control group. Nine PD patients (2 women and 7 men) completed the self-report Swallowing Quality of Life questionnaire (SWAL-QOL) before and 12 months after cZI DBS surgery. The postoperative data were compared to 9 controls. Median ages were 53 years (range, 40-70 years) for patients and 54 years (range, 42-72 years) for controls. No significant differences were found between the pre- or postoperative scores. The SWAL-QOL total scores did not differ significantly between PD patients and controls. The PD patients reported significantly lower scores in the burden subscale and the symptom scale. Patients with PD selected for cZI DBS showed good self-reported swallowing-specific quality of life, in many aspects equal to controls. The cZI DBS did not negatively affect swallowing-specific quality of life in this study.
2010-01-01
Background The zona limitans intrathalamica (ZLI) and the isthmus organizer (IsO) are two major secondary organizers of vertebrate brain development. These organizers are located at the interface of the expression domains of key patterning genes (Fezf-Irx and Otx-Gbx, respectively). To gain insights into the evolutionary origin of the ZLI, we studied Fezf in bilaterians. Results In this paper, we identified a conserved sequence motif (Fezf box) in all bilaterians. We report the expression pattern of Fezf in amphioxus and Drosophila and compare it with those of Gbx, Otx and Irx. We found that the relative expression patterns of these genes in vertebrates are fully conserved in amphioxus and flies, indicating that the genetic subdivisions defining the location of both secondary organizers in early vertebrate brain development were probably present in the last common ancestor of extant bilaterians. However, in contrast to vertebrates, we found that Irx-defective flies do not show an affected Fezf expression pattern. Conclusions The absence of expression of the corresponding morphogens from cells at these conserved genetic boundaries in invertebrates suggests that the organizing properties might have evolved specifically in the vertebrate lineage by the recruitment of key morphogens to these conserved genetic locations. PMID:20849572
Feedforward inhibitory control of sensory information in higher-order thalamic nuclei.
Lavallée, Philippe; Urbain, Nadia; Dufresne, Caroline; Bokor, Hajnalka; Acsády, László; Deschênes, Martin
2005-08-17
Sensory stimuli evoke strong responses in thalamic relay cells, which ensure a faithful relay of information to the neocortex. However, relay cells of the posterior thalamic nuclear group in rodents, despite receiving significant trigeminal input, respond poorly to vibrissa deflection. Here we show that sensory transmission in this nucleus is impeded by fast feedforward inhibition mediated by GABAergic neurons of the zona incerta. Intracellular recordings of posterior group neurons revealed that the first synaptic event after whisker deflection is a prominent inhibition. Whisker-evoked EPSPs with fast rise time and longer onset latency are unveiled only after lesioning the zona incerta. Excitation survives barrel cortex lesion, demonstrating its peripheral origin. Electron microscopic data confirm that trigeminal axons make large synaptic terminals on the proximal dendrites of posterior group cells and on the somata of incertal neurons. Thus, the connectivity of the system allows an unusual situation in which inhibition precedes ascending excitation resulting in efficient shunting of the responses. The dominance of inhibition over excitation strongly suggests that the paralemniscal pathway is not designed to relay inputs triggered by passive whisker deflection. Instead, we propose that this pathway operates through disinhibition, and that the posterior group forwards to the cerebral cortex sensory information that is contingent on motor instructions.
Kapas, S; Hinson, J P
1996-01-01
1. The experiments described in this study were carried out to investigate the role of tyrosine kinase in the acute adrenal response to peptide hormone stimulation, and to determine whether the activity of this kinase may be subject to regulation by other intracellular signalling mechanisms in the adrenal zona glomerulosa. 2. Previous studies from this laboratory have shown that angiotensin II stimulates tyrosine kinase activity in the rat adrenal cortex. This study has shown, for the first time, that endothelin-1 also stimulates tyrosine kinase activity in this tissue. 3. Using the specific inhibitor of protein kinase C (PKC) activity, Ro 31-8220, we have shown that stimulation of tyrosine kinase activity, in response to endothelin-1, angiotensin II or the phorbol ester phorbol 12-myristate 13-acetate, is at least partly dependent on increased PKC activity. 4. The data presented also provide further evidence of cross-talk between signalling systems in the adrenal cortex. Corticotrophin and its intracellular second messenger, cyclic AMP, significantly attenuate the increment in tyrosine kinase activity seen in response to each of the effectors used. 5. The results of this study provide important new evidence for the regulation of protein kinases by other intracellular second messenger systems. PMID:8611168
Analysis of ZP1 gene reveals differences in zona pellucida composition in carnivores.
Moros-Nicolás, C; Leza, A; Chevret, P; Guillén-Martínez, A; González-Brusi, L; Boué, F; Lopez-Bejar, M; Ballesta, J; Avilés, M; Izquierdo-Rico, M J
2018-01-01
The zona pellucida (ZP) is an extracellular envelope that surrounds mammalian oocytes. This coat participates in the interaction between gametes, induction of the acrosome reaction, block of polyspermy and protection of the oviductal embryo. Previous studies suggested that carnivore ZP was formed by three glycoproteins (ZP2, ZP3 and ZP4), with ZP1 being a pseudogene. However, a recent study in the cat found that all four proteins were expressed. In the present study, in silico and molecular analyses were performed in several carnivores to clarify the ZP composition in this order of mammals. The in silico analysis demonstrated the presence of the ZP1 gene in five carnivores: cheetah, panda, polar bear, tiger and walrus, whereas in the Antarctic fur seal and the Weddell seal there was evidence of pseudogenisation. Molecular analysis showed the presence of four ZP transcripts in ferret ovaries (ZP1, ZP2, ZP3 and ZP4) and three in fox ovaries (ZP2, ZP3 and ZP4). Analysis of the fox ZP1 gene showed the presence of a stop codon. The results strongly suggest that all four ZP genes are expressed in most carnivores, whereas ZP1 pseudogenisation seems to have independently affected three families (Canidae, Otariidae and Phocidae) of the carnivore tree.
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Lean, A.; Cantin, M.
1986-03-05
The authors have previously reported that atrial natriuretic factor (ANF) potently inhibits PGE or forskolin-stimulation aldosterone secretion in bovine zona glomerulosa (ZG) by acting through specific high affinity receptors. In order to evaluate the functional role of the regulatory protein N/sub i/ and the inhibition of adenylate cyclase activity (AC) in ZG, the authors have studied the effect of treatment with PT on inhibition by ANF of aldosterone production. Primary cultures of ZG were treated for 18 hours in serum-free F12 medium with (0-100 ng/ml PT). No effect of PT pretreatment was observed either on basal, PGE-stimulated or ANF-inhibited levelsmore » of steroidogenesis. When membranes prepared from control ZG were ADP-ribosylated with (/sup 32/P) NAD in the presence of PT, two toxin-specific bands with 39 Kd and 41 Kd were documented on SDS gel. Cell pretreatment with as low as 1 ng/ml drastically reduced further labelling of these two bands while higher doses completely abolished them. Since PT treatment covalently modifies completely the toxin substrate without altering ANF inhibition of adrenal steroidogenesis, the authors conclude that N/sub i/ is not involved in the mode of action of ANF on aldosterone production.« less
Hydrodynamic characteristics of the western Doñana Region (area of El Abalario), Huelva, Spain
NASA Astrophysics Data System (ADS)
Trick, Thomas; Custodio, Emilio
The Doñana region, in southwestern Spain, comprises a large and important nature reserve, the wetlands of which are affected by human activity. Planting of an extensive eucalyptus forest in the 1950s and, more recently, the use of aquifers for irrigation and water supply for some coastal tourist resorts, have altered the natural groundwater-flow system. The area of the study is the western sector of the region, called El Abalario, which is a gentle topographic elevation between the Atlantic coast and La Rocina Creek (Arroyo de la Rocina). Underneath a variable layer of eolian sands with high dunes near the coast, thick Plio-Quaternary detritic strata, mostly fine silica sands, overlie marls. Near the base there is a variable, deltaic-origin layer of coarse sands and gravels. The dome-shaped water table, inside the sands, is close to the surface everywhere except beneath the dune belt, and small, temporary, shallow lagoons are numerous. The coarse sand and gravel layer conditions groundwater flow and behaves as a semiconfined layer between sands. A cross section through the area was simulated with a model to check the validity of the conceptual groundwater-flow pattern and its sensitivity to the hydraulic parameters. The model was calibrated using parameter values obtained by pumping tests and multilevel piezometric data, and checked against the estimated groundwater discharge into La Rocina Creek. Groundwater flows peripherally to the sea coast, to La Rocina Creek, or directly east and southeastward into the Doñana marshlands, in the Guadalquivir River delta. The average net aquifer recharge rate was calculated to be between 100 and 200 mm year-1 for the area covered by brush, but is remarkably lower in the areas of eucalyptus trees. The transient-state model shows that recharge varies spatially and is not clearly proportional to annual precipitation. Phreatic evapotranspiration plays an important role in decreasing the net value of aquifer recharge to approximately 0.4-0.6 of that calculated with a soil-balance model. The cross section model was used to study the effect of groundwater ion on water-table depth by subtracting the contribution of vertical flow, calculated by a well-hydraulics formula, to the semiconfined deep aquifer. The result was a decrease in phreatic evapotranspiration, flow into La Rocina Creek, and lagoon-inundation frequency. Replacement of the eucalyptus forest with native vegetation may raise water-table levels and even reactivate old tributaries to La Rocina Creek. La région de Doñana, située dans le sud ouest de l'Espagne, comprend une importante réserve naturelle avec des zones humides, affectée par l'activité humaine. L'exploitation de vastes plantations d'eucalyptus pendant les années 50 et l'usage plus récent des nappes souterraines pour l'irrigation et l'alimentation en eau des centres touristiques côtiers ont modifié le système de flux d'eau souterraine dans cette zone. La présente étude a été réalisée dans le secteur occidental, appelé El Abalario. Ce secteur consiste en une légère élévation située entre l'Océan Atlantique et la ravine de La Rocina. Une couverture variable de sables éoliens, formant une haute crête dunaire côtière, recouvre des sédiments detritiques plio-quaternaires, déposés eux même sur des sables siliceux lesquels reposent à leur tour sur des marnes. Près de la base se trouvent des sables grossiers et des graviers d'origine deltaïque, dont l'épaisseur varie spatialement. Le flux d'eau souterraine est conditionné par l'aquifère semi confinés des graviers et des sables grossiers. Le niveau phréatique de l'aquifère libre des sables fluvio-marins est peu profond, excepté sous les dunes. On y trouve souvent des petites lagunes temporaires peu profondes. Le flux de l'eau souterraine a été simulé dans une section verticale pour vérifier le modèle hydrogéologique conceptuel et la sensibilité aux variations des paramètres. Le modèle a été calé en utilisant d'une part les valeurs des paramètres hydrauliques obtenus par des essais de pompage et d'après les données piezométriques mesurées à différentes profondeurs, et d'autre part l'apport estimé de la ravine de La Rocina. L'écoulement d'eau souterraine s'effectue par drainage latérale dans trois directions, d'une part vers la côte, d'autre part à travers la ravine de La Rocina et finalement directement vers les Marais de Doñana situés à l'est et sud-est dans le delta du fleuve Guadalquivir. Avec une pluviométrie moyenne comprise entre 550 et 600 mm, la recharge nette moyenne annuelle des nappes, pour des périodes de temps assez longues, est estimée entre 100 et 200 mm dans les aires de végétation autochtone, et elle est nettement inférieure dans les aires plantées deucalyptus. Le modèle transitoire montre que la recharge varie dans l'espace et qu'elle n'est pas clairement proportionnelle aux précipitations annuelles. L'évapotranspiration phréatique joue un rôle important et diminue la valeur nette de la recharge des nappes de 0,4 à 0,6 de la valeur calculée avec un modèle de bilan d'eau dans le sol. La section modélisée est utilisée pour étudier l'effet de l'extraction d'eau souterraine sur la profondeur du niveau phréatique en soustrayant le flux vertical, calculé grâce à une formule d'hydraulique des puits, de la nappe profonde semi-confinée. Le résultat de cette extraction est une diminution de l'évapotranspiration phréatique, du flux au niveau de la ravine de La Rocina et de la fréquence d'inondation des lagunes. La substitution de forêts d'eucalyptus par de la végétation autochtone peut permettre la remonté des niveaux phréatiques et même réactiver d'anciens ravins affluents à La Rocina. La región de Doñana, situada en el sudoeste de España, incluye una gran e importante reserva natural, cuyos humedales están siendo afectados por la actividad humana. La extensa plantación de eucaliptus en la década de 1950 y el uso más reciente de los acuíferos para riego y para abastecimiento de centros turísticos costeros han modificado el sistema de flujo del agua subterránea en esta zona. Este estudio se ha realizado en el sector occidental, llamado El Abalario. Se trata de una elevación suave situada entre el océano Atlántico y el arroyo de La Rocina. Debajo de un manto variable de arenas eólicas, que forma un alto cordón dunar costero, se encuentran sedimentos detríticos plio-cuaternarios formados por arenas silíceas finas, que hacia la base incluyen una capa de arenas gruesas y gravas de origen deltrico, los que a su vez yacen sobre margas. El flujo de agua subterránea está relacionado con niveles de gravas y gravillas semiconfinadas por las arenas fluvio-marinas que contienen el nivel freático. El nivel freático es somero excepto debajo del cordón dunar. Son frecuentes pequeñas lagunas temporales. Se ha simulado el flujo de agua subterránea en una sección para comprobar el modelo de flujo conceptual y la sensibilidad a variaciones de los parámetros. El modelo fue calibrado usando los valores de los parámetros hidráulicos obtenidos en ensayos de bombeo y datos piezométricos medidos a diferentes profundidades, y la descarga estimada al arroyo de La Rocina. La recarga de agua subterránea drena lateralmente, por un lado hacia la costa y por otro lado a través del arroyo de La Rocina, o directamente hacia las Marismas de Doñana situadas en el delta del río Guadalquivir. Con una lluvia media anual entre 550 y 600 mm, la recarga neta media estacionaria anual del acuífero, considerando periodos de tiempo largos, se estima entre 100 y 200 mm en las zonas de vegetación autóctona, y es notablemente menor en las zonas de plantación de eucaliptos. El modelo transitorio indica que la recarga varia espacialmente y no es claramente proporcional a la precipitación para periodos de un año. La evapotranspiración freática varia espacialmente y juega un papel importante; disminuye el valor neto de la recarga al acuífero para dejarlo en 0,4 a 0,6 de lo que se calcula mediante un balance de agua en el suelo. La sección modelada sirve para estudiar el efecto de la extracción de agua subterránea sobre la profundidad del nivel freático mediante la substracción del flujo vertical, que se calcula mediante una fórmula de hidráulica de pozos para el acuífero semiconfinado profundo. El resultado es una disminución de la evapotranspiración freática, del flujo al arroyo de la Rocina y de la frecuencia de inundación de las lagunas. La substitución del bosque de eucaliptus por vegetación nativa puede elevar los niveles freáticos e incluso reactivar antiguos "caños" tributarios al arroyo de La Rocina.
High Temperature Protonic Conductors by Melt Growth
2006-11-21
A.R. de Arellano-López, A. Sayir. “Microestructura y Comportamiento Plástico de Perovsquitas Conductoras Protónicas de Alta Temperatura ”. Bol. Soc...Conductores Protónicos de Alta Temperatura Crecidos por Fusión de Zona Flotante”. VII Reunión Nacional y VI Conferencia Iberoamericana (Electrocerámica...Fernández Departamento de Física de la Materia Condensada University of Seville, Sevilla, SPAIN High temperature protonic conductors (HTPC) were
Rizzoli-Córdoba, Antonio; Martell-Valdez, Liliana; Delgado-Ginebra, Ismael; Villasís-Keever, Miguel Ángel; Reyes-Morales, Hortensia; O'Shea-Cuevas, Gabriel; Aceves-Villagrán, Daniel; Carrasco-Mendoza, Joaquín; Villagrán-Muñoz, Víctor Manuel; Halley-Castillo, Elizabeth; Vargas-López, Guillermo; Muñoz-Hernández, Onofre
Evaluación del Desarrollo Infantil or Child Development Evaluation (CDE) test, a screening tool designed and validated in Mexico, classifies child development as normal (green) or abnormal (developmental lag or yellow and risk of delay or red). Population-based results of child development level with this tool are not known. The objective of this work was to evaluate the developmental level of children aged 1-59 months living in poverty (PROSPERA program beneficiaries) through application of the CDE test. CDE tests were applied by specifically trained and standardized personnel to children <5 years old who attended primary care facilities for a scheduled appointment for nutrition, growth and development evaluation from November 2013 to May 2014. There were 5,527 children aged 1-59 months who were evaluated; 83.8% (n=4,632) were classified with normal development (green) and 16.2% (n=895) as abnormal: 11.9% (n=655) as yellow and 4.3% (n=240) as red. The proportion of abnormal results was 9.9% in children <1 year of age compared with 20.8% at 4 years old. The most affected areas according to age were language at 2 years (9.35%) and knowledge at 4 years old (11.1%). Gross motor and social areas were more affected in children from rural areas; fine motor skills, language and knowledge were more affected in males. The proportion of children with abnormal results is similar to other population-based studies. The highest rate in older children reinforces the need for an early-based intervention. The different pattern of areas affected between urban and rural areas suggests the need for a differentiated intervention. Copyright © 2015 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.
Alvarado-Otegui, J A; Ceballos, L A; Orozco, M M; Enriquez, G F; Cardinal, M V; Cura, C; Schijman, A G; Kitron, U; Gürtler, R E
2012-10-01
Little is known about the sylvatic transmission cycle of Trypanosoma cruzi in the Gran Chaco ecoregion. We conducted surveys to identify the main sylvatic hosts of T. cruzi, parasite discrete typing units and vector species involved in Pampa del Indio, a rural area in the humid Argentinean Chaco. A total of 44 mammals from 14 species were captured and examined for infection by xenodiagnosis and polymerase chain reaction amplification of the hyper-variable region of kinetoplast DNA minicircles of T. cruzi (kDNA-PCR). Ten (22.7%) mammals were positive by xenodiagnosis or kDNA-PCR. Four of 11 (36%) Didelphis albiventris (white-eared opossums) and six of nine (67%) Dasypus novemcinctus (nine-banded armadillos) were positive by xenodiagnosis and or kDNA-PCR. Rodents, other armadillo species, felids, crab-eating raccoons, hares and rabbits were not infected. Positive animals were highly infectious to the bugs that fed upon them as determined by xenodiagnosis. All positive opossums were infected with T. cruzi I and all positive nine-banded armadillos with T. cruzi III. Extensive searches in sylvatic habitats using 718 Noireau trap-nights only yielded Triatoma sordida whereas no bug was collected in 26 light-trap nights. Four armadillos or opossums fitted with a spool-and-line device were successfully tracked to their refuges; only one Panstrongylus geniculatus was found in an armadillo burrow. No sylvatic triatomine was infected with T. cruzi by microscopical examination or kDNA-PCR. Our results indicate that two independent sylvatic transmission cycles of T. cruzi occur in the humid Chaco. The putative vectors of both cycles need to be identified conclusively. Copyright © 2012 Elsevier B.V. All rights reserved.
The sylvatic transmission cycle of Trypanosoma cruzi in a rural area in the humid Chaco of Argentina
Alvarado-Otegui, J.A.; Ceballos, L.A.; Orozco, M.M.; Enriquez, G.F.; Cardinal, M.V.; Cura, C.; Schijman, A.G.; Kitron, U.; Gürtler, R.E.
2012-01-01
Little is known about the sylvatic transmission cycle of Trypanosoma cruzi in the Gran Chaco ecoregion. We conducted surveys to identify the main sylvatic hosts of T. cruzi, parasite discrete typing units and vector species involved in Pampa del Indio, a rural area in the humid Argentinean Chaco. A total of 44 mammals from 14 species was captured and examined for infection by xenodiagnosis and polymerase chain reaction amplification of the hyper-variable region of kinetoplast DNA minicircles of T. cruzi (kDNA-PCR). Ten (22.7%) mammals were positive by xenodiagnosis or kDNA-PCR. Four of 11 (36%) Didelphis albiventris (white-eared opossums) and six of nine (67%) Dasypus novemcinctus (nine-banded armadillos) were positive by xenodiagnosis and or kDNA-PCR. Rodents, other armadillo species, felids, crab-eating raccoons, hares and rabbits were not infected. Positive animals were highly infectious to the bugs that fed upon them as determined by xenodiagnosis. All positive opossums were infected with T. cruzi I and all positive nine-banded armadillos with T. cruzi III. Extensive searches in sylvatic habitats using 718 Noireau trap-nights only yielded Triatoma sordida whereas no bug was collected in 26 light-trap nights. Four armadillos or opossums fitted with a spool-and-line device were successfully tracked to their refuges; only one Panstrongylus geniculatus was found in an armadillo burrow. No sylvatic triatomine was infected with T. cruzi by microscopical examination or kDNA-PCR. Our results indicate that two independent sylvatic transmission cycles of T. cruzi occur in the humid Chaco. The putative vectors of both cycles need to be identified conclusively. PMID:22771688
Fernández, María del Pilar; Cecere, María Carla; Cohen, Joel E.
2017-01-01
Human sleeping quarters (domiciles) and chicken coops are key source habitats of Triatoma infestans—the principal vector of the infection that causes Chagas disease—in rural communities in northern Argentina. Here we investigated the links among individual bug bloodmeal contents (BMC, mg), female fecundity, body length (L, mm), host blood sources and habitats. We tested whether L, habitat and host blood conferred relative fitness advantages using generalized linear mixed-effects models and a multimodel inference approach with model averaging. The data analyzed include 769 late-stage triatomines collected in 120 sites from six habitats in 87 houses in Figueroa, Santiago del Estero, during austral spring. L correlated positively with other body-size surrogates and was modified by habitat type, bug stage and recent feeding. Bugs from chicken coops were significantly larger than pig-corral and kitchen bugs. The best-fitting model of log BMC included habitat, a recent feeding, bug stage, log Lc (mean-centered log L) and all two-way interactions including log Lc. Human- and chicken-fed bugs had significantly larger BMC than bugs fed on other hosts whereas goat-fed bugs ranked last, in consistency with average blood-feeding rates. Fecundity was maximal in chicken-fed bugs from chicken coops, submaximal in human- and pig-fed bugs, and minimal in goat-fed bugs. This study is the first to reveal the allometric effects of body-size surrogates on BMC and female fecundity in a large set of triatomine populations occupying multiple habitats, and discloses the links between body size, microsite temperatures and various fitness components that affect the risks of transmission of Trypanosoma cruzi. PMID:29211791
Gürtler, Ricardo E; Fernández, María Del Pilar; Cecere, María Carla; Cohen, Joel E
2017-12-01
Human sleeping quarters (domiciles) and chicken coops are key source habitats of Triatoma infestans-the principal vector of the infection that causes Chagas disease-in rural communities in northern Argentina. Here we investigated the links among individual bug bloodmeal contents (BMC, mg), female fecundity, body length (L, mm), host blood sources and habitats. We tested whether L, habitat and host blood conferred relative fitness advantages using generalized linear mixed-effects models and a multimodel inference approach with model averaging. The data analyzed include 769 late-stage triatomines collected in 120 sites from six habitats in 87 houses in Figueroa, Santiago del Estero, during austral spring. L correlated positively with other body-size surrogates and was modified by habitat type, bug stage and recent feeding. Bugs from chicken coops were significantly larger than pig-corral and kitchen bugs. The best-fitting model of log BMC included habitat, a recent feeding, bug stage, log Lc (mean-centered log L) and all two-way interactions including log Lc. Human- and chicken-fed bugs had significantly larger BMC than bugs fed on other hosts whereas goat-fed bugs ranked last, in consistency with average blood-feeding rates. Fecundity was maximal in chicken-fed bugs from chicken coops, submaximal in human- and pig-fed bugs, and minimal in goat-fed bugs. This study is the first to reveal the allometric effects of body-size surrogates on BMC and female fecundity in a large set of triatomine populations occupying multiple habitats, and discloses the links between body size, microsite temperatures and various fitness components that affect the risks of transmission of Trypanosoma cruzi.
NASA Astrophysics Data System (ADS)
Hott, M. C.; Fonseca, L. D.; Andrade, R. G.
2011-12-01
The present study aimed at mapping some categories of Areas of Permanent Preservation (APP) for natural regeneration of semideciduous forests in the regions of Zona da Mata and Campo das Vertentes, Minas Gerais State (Figure 1), and from this to establish what impact the deployment of APP over area of pastures and subsequently milk production and carbon sequestration, considering areas of pasture as one of major factors for the dairy farming in the regions concerned. From the altimetric information from MDE, it was possible to extract morphological and morphometrical data to estimate the areas of APP. We used imagery of MODIS/Terra for extraction of the pastures areas from the vegetation index data NDVI to intersect with the estimated area of APP. In a linear or deterministic scenario of deployment of APPs over in the pasture areas considering that wich are proportionately responsible for sizing the herd, and thus for the milk production in extensive livestock, despite the existence of numerous other factors, there would be an impact 12% in the production of Campo das Vertentes region and 21.5% for the Zona da Mata. In this scenario, according to the carbon balance of forests and livestock, there would be a positive balance with the deployment of areas of permanent preservation and, subsequent promotion of natural regeneration. Considering the current grazing area of the Zona da Mata and Campo das Vertentes, 1.6 million hectares, with the carbon balance estimated at 1 ton/hectare/year, 300,000 hectares would have a balance of 5 ton/hectare/year in whole cycle of 40 years, totaling 200 tons carbon by hectare, or additional 48 million tons fixed, considering 4 tons more than pastures in the case of semideciduous forest. At the end of the cycle or forest climax, there would still be positive carbon balance, estimated as a balance of 2 ton/hectare/year. However, despite the higher carbon balance for the semideciduous forest, compared to livestock, it is important to maintain a balance between conservation of natural resources, land suitability and demand for food, especially for milk in these regions, which provide inputs for the dairy industry. The brazilian environmental legislation faces a turbulent period of change, but certainly it can contribute to increase carbon sequestration.
Novo, Sergi; Penon, Oriol; Barrios, Leonardo; Nogués, Carme; Santaló, Josep; Durán, Sara; Gómez-Matínez, Rodrigo; Samitier, Josep; Plaza, José Antonio; Pérez-García, Luisa; Ibáñez, Elena
2013-06-01
Is the attachment of biofunctionalized polysilicon barcodes to the outer surface of the zona pellucida an effective approach for the direct tagging and identification of cultured embryos? The results achieved provide a proof of concept for a direct embryo tagging system using biofunctionalized polysilicon barcodes, which could help to minimize the risk of mismatching errors (mix-ups) in human assisted reproduction technologies. Even though the occurrence of mix-ups is rare, several cases have been reported in fertility clinics around the world. Measures to prevent the risk of mix-ups in human assisted reproduction technologies are therefore required. Mouse embryos were tagged with 10 barcodes and the effectiveness of the tagging system was tested during fresh in vitro culture (n=140) and after embryo cryopreservation (n = 84). Finally, the full-term development of tagged embryos was evaluated (n =105). Mouse pronuclear embryos were individually rolled over wheat germ agglutinin-biofunctionalized polysilicon barcodes to distribute them uniformly around the ZONA PELLUCIDA surface. Embryo viability and retention of barcodes were determined during 96 h of culture. The identification of tagged embryos was performed every 24 h in an inverted microscope and without embryo manipulation to simulate an automatic reading procedure. Full-term development of the tagged embryos was assessed after their transfer to pseudo-pregnant females. To test the validity of the embryo tagging system after a cryopreservation process, tagged embryos were frozen at the 2-cell stage using a slow freezing protocol, and followed in culture for 72 h after thawing. Neither the in vitro or in vivo development of tagged embryos was adversely affected. The tagging system also proved effective during an embryo cryopreservation process. Global identification rates higher than 96 and 92% in fresh and frozen-thawed tagged embryos, respectively, were obtained when simulating an automatic barcode reading system, although these rates could be increased to 100% by simply rotating the embryos during the reading process. The direct embryo tagging developed here has exclusively been tested in mouse embryos. Its effectiveness in other species, such as the human, is currently being tested. The direct embryo tagging system developed here, once tested in human embryos, could provide fertility clinics with a novel tool to reduce the risk of mix-ups in human assisted reproduction technologies.
Woods, Stephanie E; Qi, Peimin; Rosalia, Elizabeth; Chavarria, Tony; Discua, Allan; Mkandawire, John; Fox, James G; García, Alexis
2014-01-01
The utility of cryopreserved mouse gametes for reproduction of transgenic mice depends on development of assisted reproductive technologies, including vitrification of unfertilized mouse oocytes. Due to hardening of the zona pellucida, spermatozoa are often unable to penetrate vitrified-warmed (V-W) oocytes. Laser-assisted in vitro fertilization (LAIVF) facilitates fertilization by allowing easier penetration of spermatozoa through a perforation in the zona. We investigated the efficiency of V-W C57BL/6NTac oocytes drilled by the XYClone laser, compared to fresh oocytes. By using DAP213 for cryoprotection, 83% (1,470/1,762) of vitrified oocytes were recovered after warming and 78% were viable. Four groups were evaluated for two-cell embryo and live offspring efficiency: 1) LAIVF using V-W oocytes, 2) LAIVF using fresh oocytes, 3) conventional IVF using V-W oocytes and 4) conventional IVF using fresh oocytes. First, the groups were tested using fresh C57BL/6NTac spermatozoa (74% motile, 15 million/ml). LAIVF markedly improved the two-cell embryo efficiency using both V-W (76%, 229/298) and fresh oocytes (69%, 135/197), compared to conventional IVF (7%, 12/182; 6%, 14/235, respectively). Then, frozen-thawed C57BL/6NTac spermatozoa (35% motile, 15 million/ml) were used and LAIVF was again found to enhance fertilization efficiency, with two-cell embryo rates of 87% (298/343) using V-W oocytes (P<0.05, compared to fresh spermatozoa), and 73% (195/266) using fresh oocytes. Conventional IVF with frozen-thawed spermatozoa using V-W (6%, 10/168) and fresh (5%, 15/323) oocytes produced few two-cell embryos. Although live offspring efficiency following embryo transfer was greater with conventional IVF (35%, 18/51; LAIVF: 6%, 50/784), advantage was seen with LAIVF in live offspring obtained from total oocytes (5%, 50/1,010; conventional IVF: 2%, 18/908). Our results demonstrated that zona-drilled V-W mouse oocytes can be used for IVF procedures using both fresh and frozen-thawed spermatozoa, producing live pups. The ability to cryopreserve mouse gametes for LAIVF may facilitate management of large-scale transgenic mouse production facilities.
Diana, Anna; Polizzi, Angela Maria; Santostasi, Teresa; Ratclif, Luigi; Pantaleo, Maria Giuseppina; Leonetti, Giuseppina; Iusco, Danila Rosa; Gallo, Crescenzio; Conese, Massimo; Manca, Antonio
2016-06-01
Few mutations in cis have been annotated for F508del homozygous patients. Southern Italy patients who at a first analysis appeared homozygous for the F508del mutation (n=63) or compound heterozygous for the F508del and another mutation in the cystic fibrosis transmembrane conductance regulator gene (n=155) were searched for the A238V mutation in exon 6. The allelic frequency of the complex allele [A238V;F508del] was 0.04. When the whole data set was used (comprised also of 56 F508del/F508del and 34 F508del/other mutation controls), no differences reached the statistical significance in the clinical parameters, except chloride concentrations which were lower in [A238V;F508del]/other mutation compared with F508del/other mutation (P=0.03). The two study groups presented less complications than the control groups. Within the minimal data set (34 F508del/F508del, 27 F508del/other mutation, 4 [A238V;F508del]/F508del cases and 5 [A238V;F508del]/other mutation cases); that is, presenting all the variables in each patient, forced expiratory volume in 1 s and forced vital capacity presented a trend to lower levels in the study groups in comparison with the F508del/F508del group, and C-reactive protein approximated statistically significant higher levels in the [A238V;F508del]/other mutation as compared with F508del/F508del patients (P=0.09). The analysis of statistical dependence among the variables showed a significant anticorrelation between chloride and body mass index in the [A238V;F508del]/other mutation group. In conclusion, the complex allele [A238V;F508del] seems to be associated with less general complications than in the control groups, on the other hand possibly giving a worse pulmonary phenotype and higher systemic/local inflammatory response. These findings have implications for the correct recruitment and clinical response of F508del patients in the clinical trials testing the new etiological drugs for cystic fibrosis.
NASA Astrophysics Data System (ADS)
de Luna, Elena; Guzmán, Gema; Gómez, José A.
2014-05-01
The optimization of water use in a semi-arid climate is based on an optimal use of rainwater adopting management practices that prevent and/or control runoff. This is a key point for increasing the economic and environmental sustainability of agriculture due to the minimization of diffuse pollution associated to runoff and to sediment and chemical transport. One strategy is the establishment of vegetative filters strips that prevent pesticides (Stehle et al. 2011), herbicides (Vianello et al. 2005), fertilizers (Withers et al. 2009) and runoff-sediment (Campo-Bescós et al. 2013) from entering streams or surface water reservoirs. To evaluate the short-term risks associated with the use of herbicides a trial was designed in two olive groves located in Benacazón (Sevilla) and Cabra (Córdoba) both with an average steepness of 11%. Two different management systems were evaluated, bare soil and bare soil with vegetative filter strips. Pre-emergence herbicides were applied and analysed at the beginning of the trial by chromatography GC-MS and after each rainfall event both in soil and sediment. Runoff and soil losses were measured, as well. The results obtained from this study show that soil management practices such as, the use of vegetative filter strips results in a reduction of soil losses and runoff. This it is translated in the improvement of soil quality and a reduction of water pollution caused by the use of herbicides. This information will improve the understanding of insufficiently known aspects and it will help to increase the knowledge for a better implementation of sustainable management practices at a farm scale and at larger temporal scale. References: Campo-Bescós, M. A., Muñoz-Carpena, R., & Kiker, G. (2013) Influencia del suelo en la eficiencia de la implantación de filtros verdes en un distrito de riego por superficie en medio árido. En Estudios de la Zona no Saturada del Suelo, Vol. XI: 183-187. Stehle, S., Elsaesser, D., Gregoire, C., Imfeld, G., Niehaus, E., Passeport, E., Payraudeau, S., Schäfera, R., Tournebize, J., & Schulz, R. (2011). Pesticide risk mitigation by vegetated treatment systems: a meta-analysis. Journal of Environmental Quality, 40: 1068-1080. Vianello, M., Vischetti, C., Scarponi, L., & Zanin, G. (2005). Herbicide losses in runoff events from a field with a low slope: role of a vegetative filter strip. Chemosphere, 61: 717-725. Withers, P. J. A., Hartikainen, H., Barberis, E., Flynn, N. J., & Warren, G. P. (2009). The effect of soil phosphorus on particulate phosphorus in land runoff. European Journal of Soil Science 60: 994-1004.
Somers, George T; Strasser, Roger; Jolly, Brian
2007-01-01
There is abundant evidence that rural origin is an influence on rural career choice. Rural origin is widely used to select students to be supported into programs designed to address the rural medical workforce shortage. What is not as clear is how many years of rural upbringing are required to have a maximal effect on rural career choice. Neither is the place of having a sense of rural background well understood. A cross-sectional self-completed paper-based survey of all students in years one through four of the Monash University medical course was undertaken in 2003. The survey included a scale to measure stated rural career intention as well as questions about the number of years of rural upbringing and whether students had a sense of rural background. The Rural Intention score was divided into three categories: strong urban intent, strong rural intent, and an intermediate, less certain intent. There was an 88% (n = 399) response rate from students holding Commonwealth Supported Places. Approximately 30% of these claimed a sense of rural background, and 28% had more than 8 years of rural upbringing. Twenty-five percent stated a strong intention to choose a rural career and 34.5% had strong urban intent. The remaining 40.5% were in the intermediate group. Almost all students (97.5%) with over 5 years of rural upbringing had developed a sense of rural background, and almost all (97.5%) with less than 5 years' rural upbringing denied a sense of rural background. Rural intent was high for those with a sense of rural background and those with more than 8 years of rural upbringing, but the students who had had from 4 to 8 years of rural upbringing mainly fell into the 'uncertain' category. In this cohort of almost 400 Australian medical students, a sense of rural background developed at a clear point, around 5 years of rural upbringing. Students with a sense of rural background were likely to develop a strong rural intent several years before similar students who had failed to make this connection with a rural community. This latter group displayed uncertainty toward a rural career choice, possibly due to unfamiliarity. Unlike those with strong urban intent, these students have not excluded a rural career and should be supported. The inclusion of a measure of the intention of students to work in a rural environment is likely to increase the reliability and validity of selection procedures.
A Compilation Catalog in the Direction of the Galactic Center.
1983-01-18
and Argelander 1890) 3) Catalogo de Zonas Estrellas (GA; Gould 1884a, b) 4) Catalogue of 12441 Stars for the Epoch 1880 (Cp 80; Stone 1881) 2 5...Catalogo General Argentino (Gou; Gould 1886) 6) Catalogo de 15200 Estrellas (Cord B; Perrine 1914) 7) Albany Zone Catalogue of 8276 Stars Between -200 and...Astrografico (AC: Perrine 1927a, b, 1928, 1931, 1932, 1933) 10) Catalogo de 6429 Estrellas de Repere (G; Guerin 1934) 11) Cape Photographic Catalogue
Illmensee, K; Kaskar, K; Zavos, P M
2006-08-01
This study was designed to compare the developmental potential of individual blastomeres derived from 2-, 4-, 6- and 8-cell mouse embryos cultured with and without zona pellucida (ZP). In the first series, one, three, five and seven blastomeres were biopsied from 2-, 4-, 6- and 8-cell embryos respectively, and inserted individually into empty ZP recipients, leaving the remaining blastomere within its original ZP. In the second series, the same protocol was used except that the biopsied blastomeres were cultured without ZP and compared with the remaining blastomere within its original ZP. For the first series, individual blastomeres derived from 2-, 4-, 6- and 8-cell embryos cultured with ZP showed blastocyst development of 82.4, 68.6, 44.4 and 23.1% respectively, with corresponding hatching rates of 70.6, 60.0, 25.9 and 7.7%. For the second series, individual blastomeres cultured without ZP progressed with blastocyst development of 73.3, 64.5, 35.7 and 22.7% respectively. Blastocyst multiplication was achieved most efficiently when using individual blastomeres from 4- and 6-cell embryos. This is the first report on comparative in-vitro propagation of single blastomeres derived from various cleavage stages in a mammalian species. Blastomere cloning with its multiple applications may be envisaged for human assisted reproductive technologies.
Gamete competence assessment by polarizing optics in assisted reproduction.
Montag, Markus; Köster, Maria; van der Ven, Katrin; van der Ven, Hans
2011-01-01
The purpose of this study was first to give an overview of the historical development of polarization microscopy, second to describe the various applications of this technique in assisted reproduction techniques (ART) and third to discuss the potential benefit of polarization microscopy as a predictor for IVF success. The history of polarization microscopy was undertaken by performing a backward search in the scientific literature using Google and internet sites of several Societies for Microscopy and Cell Biology. Studies of polarization microscopy in ART were identified by using a systematic literature search in PubMed and Scopus. A total of 62 articles were identified by the direct search and further relevant articles were found by screening the cited literature in these articles. The topics relevant for assisted reproduction were spindle and zona imaging in combination with IVF success, meiotic cell cycle progression, pharmaceutical studies and cryopreservation. A separate topic was the use of sperm birefringence in ART. The majority of studies are observational studies and were not performed in a randomized manner and there is no direct comparison of techniques using other gamete selection markers. Despite this, most studies show that polarization microscopy may help us to further increase our knowledge on gametes and meiosis. Whether certain applications such as spindle or zona imaging may lead to an increase in IVF success is unclear at present. Publications on the use of polarization microscopy on sperm are still very limited.
Gupta, Neha; Shrestha, Abhinav; Panda, Amulya Kumar; Gupta, Satish Kumar
2013-07-01
Affinity tags can interfere in various physicochemical properties and immunogenicity of the recombinant proteins. In the present study, tag-free recombinant fusion protein encompassing promiscuous T cell epitope of tetanus toxoid [TT; amino acid (aa) residues 830-844] followed by dilysine linker and dog zona pellucida glycoprotein-3 (ZP3; aa residues 23-348) (TT-KK-ZP3) was expressed in Escherichia coli. The recombinant protein, expressed as inclusion bodies (IBs), was purified by isolation of IBs, processed to remove host cell proteins, followed by solubilization and refolding. A specific 39 kDa protein including ZP3 was identified by SDS-PAGE. CD spectra showed the presence of α-helices and β-sheets, and fluorescent spectroscopy revealed emission maxima of 265 A.U. at 339 nm for refolded protein and showed red shift in the presence of 6 M guanidine hydrochloride. Immunization of inbred FvB/J female mice with purified recombinant TT-KK-ZP3 (25 μg/animal) led to generation of high antibody titers against the recombinant protein. The antibodies reacted specifically with ZP matrix surrounding mouse oocytes. Immunized mice showed significant reduction in fertility as compared to the control group. The studies described herein provide a simple method to produce and purify tag-free recombinant protein for the development of a contraceptive vaccine.
Tanihara, Fuminori; Nakai, Michiko; Men, Nguyen Thi; Kato, Noriko; Kaneko, Hiroyuki; Noguchi, Junko; Otoi, Takeshige; Kikuchi, Kazuhiro
2014-04-01
The zona pellucida (ZP) is considered to play important roles in the prevention of polyspermy in mammalian oocytes. However, in pigs we have shown that the presence of the ZP accelerates sperm penetration into the ooplasm during in vitro fertilization (IVF). In the present study, we investigated the effects of the ZP on sperm binding, acrosomal status, and functional exposure of IZUMO, a critical factor involved in sperm-egg fusion, during IVF in pigs. We evaluated the numbers and acrosomal statuses of sperm binding to the ZP and oolemma, and being present in the ZP and perivitelline space (PVS) using ZP-intact and ZP-free oocytes. More sperm bound to the ZP than to the oolemma. The average number of sperm present in the PVS was 0.44-0.51 per oocyte, and all sperm had lost their acrosomes. The proportion of sperm that were immunopositive for anti-IZUMO antibody was significantly higher after they were passing or had passed through the ZP. Furthermore, addition of anti-IZUMO antibody to the fertilization medium significantly inhibited the penetration of sperm into ZP-free oocytes. These results suggest that, in pigs, the ZP induces the acrosome reaction, which is associated with the functional exposure of IZUMO, resulting in completion of fertilization. © 2014 Japanese Society of Animal Science.
Schoen, K; Plendl, J; Gabler, C; Kaessmeyer, S
2015-06-01
Ovaries are highly complex organs displaying morphological, molecular and functional differences between their cortical zona parenchymatosa and medullary zona vasculosa, and also between the different cyclic luteal stages. Objective of the present study was to validate expression stability of twelve putative reference genes (RGs) in bovine ovaries, considering the intrinsic heterogeneity of bovine ovarian tissue with regard to different luteal stages and intra-ovarian localizations. The focus was on identifying RGs, which are suitable to normalize RT-qPCR results of ovaries collected from clinical healthy cattle, irrespective of localization and the hormonal stage. Expression profiles of twelve potential reference genes (GAPDH, ACTB, YWHAZ, HPRT1, SDHA, UBA52, POLR2C, RPS9, ACTG2, H3F3B, RPS18 and RPL19) were analysed. Evaluation of gene expression differences was performed using genorm, normfinder, and bestkeeper software. The most stably expressed genes according to genorm, normfinder and bestkeeper approaches contained the candidates H3F3B, RPS9, YWHAZ, RPS18, POLR2C and UBA52. Of this group, the genes YWHAZ, H3F3B and RPS9 could be recommended as best-suited RGs for normalization purposes on healthy bovine ovaries irrespective of the luteal stage or intra-ovarian localization. © 2014 Blackwell Verlag GmbH.
Aurelia aurita (Cnidaria) Oocytes' Contact Plate Structure and Development
Adonin, Leonid S.; Shaposhnikova, Tatyana G.; Podgornaya, Olga
2012-01-01
One of the A. aurita medusa main mesoglea polypeptides, mesoglein, has been described previously. Mesoglein belongs to ZP-domain protein family and therefore we focused on A.aurita oogenesis. Antibodies against mesoglein (AB RA47) stain the plate in the place where germinal epithelium contacts oocyte on the paraffin sections. According to its position, we named the structure found the “contact plate”. Our main instrument was AB against mesoglein. ZP-domain occupies about half of the whole amino acid sequence of the mesoglein. Immunoblot after SDS-PAGE and AU-PAGE reveals two charged and high Mr bands among the female gonad germinal epithelium polypeptides. One of the gonads' polypeptides Mr corresponds to that of mesogleal cells, the other ones' Mr is higher. The morphological description of contact plate formation is the subject of the current work. Two types of AB RA47 positive granules were observed during progressive oogenesis stages. Granules form the contact plate in mature oocyte. Contact plate of A.aurita oocyte marks its animal pole and resembles Zona Pellucida by the following features: (1) it attracts spermatozoids; (2) the material of the contact plate is synthesized by oocyte and stored in granules; (3) these granules and the contact plate itself contain ZP domain protein(s); (4) contact plate is an extracellular structure made up of fiber bundles similar to those of conventional Zona Pellucida. PMID:23185235
DOE Office of Scientific and Technical Information (OSTI.GOV)
Demura, T.; Driscoll, W.J.; Lee, Y.C.
1991-01-01
Nuclei of the guinea pig adrenal cortex contain a protein that specifically binds progesterone and that, biochemically, is clearly distinct from the classical progesterone receptor. The adrenocortical nuclear progesterone-binding protein has now been purified more than 2000-fold by steroid-affinity chromatography with a 75% yield. The purified protein preparation demonstrated three major bands on sodium dodecyl sulfate-polyacrylamide gel of 79K, 74K, and 50K. To determine which of the three might represent the progesterone-binding protein, steroid photoaffinity labeling was performed which resulted in the specific and exclusive labeling of a 50K band. Thus, the adrenocortical nuclear progesterone-binding protein appears to be distinctmore » from the classical progesterone receptor not only biochemically, but also on the basis of molecular size. To test whether the adrenocortical nuclear progesterone-binding protein can be hormonally stimulated, guinea pigs were treated with ACTH. The chronic administration of ACTH caused a 4- to 6-fold increase in the specific progesterone binding capacity without a change in the binding affinity. There appeared to be no significant difference in nuclear progesterone binding between the zona fasciculata and zona reticularis. This finding suggests a mediating role for the progesterone-binding protein in ACTH action. In addition, the nuclear progesterone-binding protein bound to nonspecific DNA sequences, further suggesting a possible transcriptional regulatory role.« less
Contreras Lopez, William Omar; Azevedo, Angelo R; Cury, Rubens G; Alencar, Francisco; Neville, Iuri S; Reis, Paul R; Navarro, Jessie; Monaco, Bernardo; da Silva, Fabio E Fernandes; Teixeira, Manoel J; Fonoff, Erich T
2016-02-01
Reporting the outcome of two patients who underwent unilateral ablative stereotactic surgery to treat pharmacologic resistant posttraumatic tremor (PTT). We present two patients (31 and 47 years old) with refractory PTT severely affecting their quality of life. Under stereotactic guidance, refined by T2-weighted magnetic resonance imaging and double-channel multiunit microelectrode recording (MER), three sequential radiofrequency lesions were performed in the caudal zona incerta (cZi) up to the base of thalamus (VOP). Effects of cZi/VOP lesion were prospectively rated with a tremor rating scale. Both patients demonstrated intraoperative tremor suppression with sustained results up to 18 months follow-up, with improvement of 92% and 84%, respectively, on the tremor rating scale. Tremor improvement was associated with enhancement functionality and quality of life for the patients. The patients returned to their work after the procedure. No adverse effects were observed up to the last follow-up. Radiofrequency lesion of the cZi/VOP target was effective for posttraumatic tremor in both cases. The use of T2-weighted images and MER was found helpful in increasing the precision and safety of the procedure, because it leads the RF probe by relying on neighbor structures based on thalamus and subthalamic nucleus. Copyright © 2016 Elsevier Inc. All rights reserved.
Mouse SLLP1, a sperm lysozyme-like protein involved in sperm-egg binding and fertilization.
Herrero, María Belén; Mandal, Arabinda; Digilio, Laura C; Coonrod, Scott A; Maier, Bernhard; Herr, John C
2005-08-01
This study demonstrates the retention of mouse sperm lysozyme-like protein (mSLLP1) in the equatorial segment of spermatozoa following the acrosome reaction and a role for mSLLP1 in sperm-egg binding and fertilization. Treatment of cumulus intact oocytes with either recmSLLP1 or its antiserum resulted in a significant (P < or = 0.05) inhibition of fertilization. Co-incubation of zona-free mouse oocytes with capacitated mouse spermatozoa in the presence of varying concentrations of anti-recmSLLP1 serum or recmSLLP1 also inhibited sperm-oolemma binding. A complete inhibition of binding and fusion of spermatozoa to the oocyte occurred at 12.5 muM concentration of recmSLLP1, while conventional chicken and human lysozymes did not block sperm-egg binding. mSLLP1 showed receptor sites in the perivitelline space as well as on the microvillar region of the egg plasma membrane. The retention of mSLLP1 in the equatorial segment of acrosome-reacted sperm, the inhibitory effects of both recmSLLP1 and antibodies to SLLP1 on in vitro fertilization with both cumulus intact and zona-free eggs, and the definition of complementary SLLP1-binding sites on the egg plasma membrane together support the hypothesis that a c lysozyme-like protein is involved in the binding of spermatozoa to the egg plasma membrane during fertilization.
Orexin Gene Transfer into Zona Incerta Neurons Suppresses Muscle Paralysis in Narcoleptic Mice
Liu, Meng; Konadhode, RodaRani; Begum, Suraiya; Pelluru, Dheeraj; Gerashchenko, Dmitry; Sakurai, Takeshi; Yanagisawa, Masashi; van den Pol, Anthony N.
2011-01-01
Cataplexy, a sudden unexpected muscle paralysis, is a debilitating symptom of the neurodegenerative sleep disorder, narcolepsy. During these attacks, the person is paralyzed, but fully conscious and aware of their surroundings. To identify potential neurons that might serve as surrogate orexin neurons to suppress such attacks, the gene for orexin (hypocretin), a peptide lost in most human narcoleptics, was delivered into the brains of the orexin-ataxin-3 transgenic mouse model of human narcolepsy. Three weeks after the recombinant adenoassociated virus (rAAV)-mediated orexin gene transfer, sleep–wake behavior was assessed. rAAV-orexin gene delivery into neurons of the zona incerta (ZI), or the lateral hypothalamus (LH) blocked cataplexy. Orexin gene transfer into the striatum or in the melanin-concentrating hormone neurons in the ZI or LH had no such effect, indicating site specificity. In transgenic mice lacking orexin neurons but given rAAV-orexin, detectable levels of orexin-A were evident in the CSF, indicating release of the peptide from the surrogate neurons. Retrograde tracer studies showed that the amygdala innervates the ZI consistent with evidence that strong emotions trigger cataplexy. In turn, the ZI projects to the locus ceruleus, indicating that the ZI is part of a circuit that stabilizes motor tone. Our results indicate that these neurons might also be recruited to block the muscle paralysis in narcolepsy. PMID:21508228
Arsenic contamination of groundwater: Mitigation strategies and policies
NASA Astrophysics Data System (ADS)
Alaerts, Guy J.; Khouri, Nadim
Contamination of groundwater by arsenic from natural geochemical sources is at present a most serious challenge in the planning of large-scale use of groundwater for drinking and other purposes. Recent improvements in detection limits of analytical instruments are allowing the correlation of health impacts such as cancer with large concentrations of arsenic in groundwater. However, there are at present no known large-scale technological solutions for the millions of people-mostly rural-who are potentially affected in developing countries. An overall framework of combating natural resource degradation is combined with case studies from Chile, Mexico, Bangladesh and elsewhere to arrive at a set of strategic recommendations for the global, national and local dimensions of the arsenic ``crisis''. The main recommendations include: the need for flexibility in the elaboration of any arsenic mitigation strategy, the improvement and large-scale use of low-cost and participatory groundwater quality testing techniques, the need to maintain consistent use of key lessons learned worldwide in water supply and sanitation and to integrate arsenic as just one other factor in providing a sustainable water supply, and the following of distinct but communicable tracks between arsenic-related developments and enhanced, long-term, sustainable water supplies. La contamination des eaux souterraines par l'arsenic provenant de sources naturelles est actuellement un sujet des plus graves dans l'organisation d'un recours à grande échelle des eaux souterraines pour la boisson et d'autres usages. De récentes améliorations dans les limites de détection des équipements analytiques permettent de corréler les effets sur la santé tels que le cancer à de fortes concentrations en arsenic dans les eaux souterraines. Toutefois, il n'existe pas actuellement de solutions technologiques à grande échelle connues pour des millions de personnes, surtout en zones rurales, qui sont potentiellement affectées dans les pays en développement. Un cadre d'ensemble pour lutter contre la dégradation naturelle des ressources est associé à des études de cas au Chili, au Mexique, au Bangladesh et ailleurs afin d'établir un ensemble de recommandations stratégiques pour les dimensions globale, nationale et locale de la «crise» de l'arsenic. Les principales recommandations sont les suivantes: le besoin d'une flexibilité pour élaborer une stratégie de diminution de l'arsenic, l'amélioration et l'utilisation à grande échelle de techniques peu coûteuses et associant les populations pour tester la qualité de l'eau souterraine, le besoin de maintenir un usage logique des leçons clés acquises de par le monde pour l'alimentation en eau et la santé publique, celui d'intégrer l'arsenic simplement comme un autre facteur pour assurer une alimentation durable en eau, et pour suivre des pistes distinctes mais communicables entre les développements liés à l'arsenic et les alimentations durables en eau mises en valeurs à long terme. La contaminación de las aguas subterráneas con arsénico procedente de fuentes geoquímicas naturales es actualmente uno de los retos principales de la planificación a gran escala de las aguas subterráneas para uso de boca y otros fines. Las recientes mejoras en los límites de detección del instrumental analítico permiten correlacionar impactos en la salud tales como el cáncer con concentraciones elevadas de arsénico en las aguas subterráneas. Sin embargo, a fecha de hoy no existen soluciones tecnológicas de gran escala para millones de personas-población principalmente rural-que están potencialmente afectadas en los países en vías de desarrollo. Se combina un enfoque general para combatir la degradación de los recursos naturales con estudios concretos de Chile, México, Bangladesh y cualquier otro lugar que permita obtener un conjunto de recomendaciones estratégicas para las dimensiones global, nacional y local de la ``crisis'' del arsénico. Las recomendaciones principales incluyen la necesidad de flexibilizar la elaboración de cualquier estrategia de mitigación del arsénico la mejora y uso a gran escala de técnicas de muestreo de las aguas subterráneas que sean económicas y participativas; la necesidad de mantener un uso coherente de las lecciones clave aprendidas a nivel mundial en el suministro y saneamiento del agua y de integrar el arsénico como otro factor más en la consecución de un suministro sustentable de agua; y el seguimiento de trazas distintas pero comunicables entre los desarrollos relacionados con el arsénico y los abastecimientos de agua sustentables a largo plazo.
The 'rural pipeline' and retention of rural health professionals in Europe's northern peripheries.
Carson, Dean B; Schoo, Adrian; Berggren, Peter
2015-12-01
The major advance in informing rural workforce policy internationally over the past 25 years has been the recognition of the importance of the 'rural pipeline'. The rural pipeline suggests that people with 'rural origin' (who spent some childhood years in rural areas) and/or 'rural exposure' (who do part of their professional training in rural areas) are more likely to select rural work locations. What is not known is whether the rural pipeline also increases the length of time professionals spend in rural practice throughout their careers. This paper analyses data from a survey of rural health professionals in six countries in the northern periphery of Europe in 2013 to examine the relationship between rural origin and rural exposure and the intention to remain in the current rural job or to preference rural jobs in future. Results are compared between countries, between different types of rural areas (based on accessibility to urban centres), different occupations and workers at different stages of their careers. The research concludes that overall the pipeline does impact on retention, and that both rural origin and rural exposure make a contribution. However, the relationship is not strong in all contexts, and health workforce policy should recognise that retention may in some cases be improved by recruiting beyond the pipeline. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Hashizume, Cary T; Woloschuk, Wayne; Hecker, Kent G
2015-01-01
There is a paucity of research regarding veterinary students' attitudes toward the rural environment and rural veterinary practice and how these attitudes might change over the course of a veterinary medicine program that includes rural clinical experience. Using a 23-item questionnaire, attitudes toward rural lifestyle, rural work-life balance, opportunities for career and skill development in rural veterinary practice, and inter-professional teamwork in the rural environment were assessed at the beginning and completion of a four-year veterinary medicine program. Eighty-six students (74.4% female) were included in this Canadian study over a six-year period. Thirty-one participants (36.1%) were rural students. Overall, students' attitudes toward the rural lifestyle, rural work-life balance, and inter-professional teamwork in rural veterinary practice all significantly decreased (p<.001) over the course of the program. As compared to urban students, rural students had significantly higher rural lifestyle scores at both the beginning (p<.001) and end (p<.01) of the veterinary medicine program. A less positive attitude toward living and working in a rural environment could influence students to exclude rural veterinary practice as a career choice. Rural clinical experiences designed to sustain or increase veterinary student interest in rural practice may not be sufficient to support positive rural attitudes. Given the demand for rural veterinary services in developed countries, the implications of this study may extend beyond Canada.
Self-efficacy reduces the impact of social isolation on medical student's rural career intent.
Isaac, Vivian; Pit, Sabrina Winona; McLachlan, Craig S
2018-03-20
Social isolation in medical students is a subjective experience that may influence medical career decision making. Rural self-efficacy has been shown to influence rural career intentions following a rural clinical placement, however its impact on social isolation during a rural clinical placement has not been previously modeled. The objective of this study is to explore whether self-perception of social isolation is associated with rural career intent in rural medical students. Secondly, to determine whether self-efficacy influences the association between social isolation and rural career intent. 2015 data, from a cross-sectional survey of the National Federation of Rural Australian Medical Educators (FRAME) study. Among 619 medical students attending rural clinical schools (RCS), rural career intent was assessed. This included intended rural location for either postgraduate medical specialist or generalist training or completion of that training. Self-efficacy beliefs in rural medical practice were based on a validated scale consisting of six questions. Social isolation was measured asking students whether they felt socially isolated during their RCS placement. 31.3% of surveyed students self-reported feeling socially isolated during their rural placement. Social isolation was associated with reduced rural career intent after controlling for gender, rural background, RCS preference, RCS support and wellbeing. In step-wise logistic regression the association between social isolation and rural intent disappeared with the inclusion of rural self-efficacy. Social isolation during a rural clinical placement is commonly reported and is shown to reduce rural career intent. High levels of rural clinical self-efficacy reduce the effects of social isolation on future rural workforce intentions.
Walker, Judith H; Dewitt, Dawn E; Pallant, Julie F; Cunningham, Christine E
2012-01-01
Health workforce shortages are a major problem in rural areas. Australian medical schools have implemented a number of rural education and training interventions aimed at increasing medical graduates' willingness to work in rural areas. These initiatives include recruiting students from rural backgrounds, delivering training in rural areas, and providing all students with some rural exposure during their medical training. However there is little evidence regarding the impact of rural exposure versus rural origin on workforce outcomes. The aim of this study is to identify and assess factors affecting preference for future rural practice among medical students participating in the Australian Rural Clinical Schools (RCS) Program. Questionnaires were distributed to 166 medical students who had completed their RCS term in 2006; 125 (75%) responded. Medical students were asked about their preferred location and specialty for future practice, their beliefs about rural work and life, and the impact of the RCS experience on their future rural training and practice preferences. Almost half the students (47%; n=58) self-reported a 'rural background'. Significantly, students from rural backgrounds were 10 times more likely to prefer to work in rural areas when compared with other students (p<0.001). For those preferring general practice, 80% (n=24) wished to do so rurally. Eighty-five per cent (n=105) of students agreed that their RCS experience increased their interest in rural training and practice with 62% (n=75) of students indicating a preference for rural internship/basic training after their RCS experience. A substantial percentage (86%; n=108) agreed they would consider rural practice after their RCS experience. This baseline study provides significant evidence to support rural medical recruitment and retention through education and training, with important insights into the factors affecting preference for future rural practice. By far the most significant predictor of rural practice intention is recruitment of students with a rural background who also undertake an RCS placement. This research also demonstrates significant demand for post-graduate rural training places, including specialty places, as RCS graduates become junior doctors and vocational trainees.
Photovoltaic generating systems in rural schools in Neuquen Province, Argentina
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lawand, T.A.; Campbell, J.
1997-12-01
During the period 1994-95, solar photovoltaic systems were installed at a number of schools in Neuquen Province, Argentina, by the Provincial electric utility, Ente Provincial de Energia del Neuquen. This was undertaken with funds provided by the Inter-American Development Bank. In all, there are 12 schools that have had photovoltaic generating systems installed. These generating systems are designed to provide electricity for the basic needs at the schools: primarily for lighting, and to operate small electrical appliances such as communication radios, televisions, VCR`s, AM/FM and short-wave radios. They do not provide enough energy to operate large consumption appliances such asmore » washing machines, microwaves, refrigerators, power tools, etc. The program of provision of PV systems was supplemented with training on simple systems for cooking food or drying fruit, etc. These techniques are primarily intended for demonstration at the schools thus serving an educational role with the hope that they will be transmitted in time to the families of the students where the need is manifested the most.« less
Canosa, S; Adriaenssens, T; Coucke, W; Dalmasso, P; Revelli, A; Benedetto, C; Smitz, J
2017-05-01
Do the mRNA expression levels of zona pellucida (ZP) genes, ZP1, 2, 3 and 4 in oocyte and cumulus cells (CC) reveal relevant information on the oocyte? The ZP mRNA expression in human oocytes is related to oocyte maturity, zona inner layer (IL) retardance and fertilization capacity. ZP structure and birefringence provide useful information on oocyte cytoplasmic maturation, developmental competence for embryonic growth, blastocyst formation and pregnancy. In order to understand the molecular basis of morphological changes in the ZP, in the current study, the polarized light microscopy (PLM) approach was combined with analysis of the expression of the genes encoding ZP1, 2, 3 and 4, both in the oocytes and in the surrounding CC. This is a retrospective study comprising 98 supernumerary human cumulus oocyte complexes (COC) [80 Metaphase II (MII), 10 Metaphase I (MI) and 8 germinal vesicle (GV)] obtained from 39 patients (median age 33.4 years, range 22-42) after controlled ovarian stimulation. Single oocytes and their corresponding CC were analysed. Oocytes were examined using PLM, and quantitative RT-PCR was performed for ZP1, 2, 3 and 4 in these individual oocytes and their CC. Ephrin-B2 (EFNB2) mRNA was measured in CC as a control. Presence of ZP3 protein in CC and oocytes was investigated using immunocytochemistry. Data were analysed using one-parametric and multivariate analysis and were corrected for the potential impact of patient and cycle characteristics. Oocytes contained ZP1/2/3 and 4 mRNA while in CC only ZP3 was quantifiable. Also ZP3 protein was detected in human CC. When comparing mature (MII) and immature oocytes (MI/GV) or their corresponding CC, ZP1/2 and 4 expression was lower in mature oocytes compared to the expression in immature oocytes (all P < 0.05) and ZP3 expression was lower in the CC of mature oocytes compared to the expression in CC of immature oocytes (P < 0.05). This coincided with a significantly smaller IL-ZP area and thickness in mature oocytes than in immature oocytes (all P < 0.05). In mature oocytes, IL-ZP retardance was significantly correlated with the expression of all four ZP mRNAs (all P < 0.05). The oocyte ZP3 expression was the main predictor of the fertilization capacity, next to IL-retardance and IL-thickness. Using stepwise regression analysis, IL-thickness combined with EFNB2 expression in CC and the patient's ovarian response resulted in a noninvasive oocyte fertilization prediction model. Not applicable. This is a retrospective study and the relation of oocyte mRNA levels to fertilization capacity is indirect as oocyte gene expression analysis required lysis of the oocyte. Overall relations between PLM observations, mRNA expression changes and intrinsic oocyte competence were successfully documented. As such PLM and CC gene expression are confirmed as valuable noninvasive techniques to evaluate oocyte competence. This study was funded by University of Torino, Italy, WFWG UZ-Brussel and Agentschap voor Innovatie door Wetenschap en Technologie IWT 110680, Belgium. All authors declare that their participation in the study did not involve actual or potential conflicts of interests. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com
77 FR 31032 - National Institute on Aging; Notice of Closed Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-24
... applications. Place: Marina del Rey Hotel, 13534 Bali Way, Marina del Rey, CA 90292. Contact Person: Bita... applications. Place: Marina del Rey Hotel, 13534 Bali Way, Marina del Rey, CA 90292. Contact Person: Ramesh... and evaluate grant applications. Place: Marina del Rey Hotel, 13534 Bali Way, Marina del Rey, CA 90292...
Rural nursing education: a photovoice perspective.
Leipert, Beverly; Anderson, Emma
2012-01-01
For many rural Canadians nursing care is the primary and often the sole access point to health care. As such, rural nurses are an invaluable resource to the health and wellbeing of rural populations. However, due to a nursing workforce that is aging and retiring, limited resources and support, healthcare reform issues, and other factors, these rural professionals are in short supply. Because of limited opportunities to learn about rural practice settings, nursing students may be reluctant to select rural practice locations. Relevant and effective educational initiatives are needed to attract nursing students to underserved rural and remote communities so that rural people receive the health care they require. The purpose of this study was to explore the use of the innovative research approach called photovoice as an educational strategy to foster learning about and interest in rural locations and rural nursing as future practice settings. Fostering of interest in rural may help to address nursing workforce shortages in rural settings. Thirty-eight third and fourth year nursing and health sciences students enrolled in an elective 'Rural Nursing' course used the qualitative research method photovoice to take photographs that represented challenges and facilitators of rural nursing practice. They then engaged in written reflection about their photos. Photos were to be taken in rural settings of their choice, thus fostering both urban and rural student exposure to diverse rural communities. One hundred forty-four photos and reflections were submitted, representing students' appreciation of diverse facilitators and challenges to rural nursing practice. Facilitators included technology, a generalist role, strong sense of community, and slower pace of life. Challenges included inadequate rural education in undergraduate nursing programs, professional isolation, safety issues, few opportunities for professional development, lack of anonymity, and insider/outsider status. Exemplar photos and reflections are provided. The photovoice research approach used in this rural education endeavour proved to be very useful in fostering students' exposure to, interest in, and understanding of rural settings and their influence on rural nursing practice. Photovoice is also recommended for use in rural courses other than nursing. Suggested strategies include group photovoice experience and the expansion of reflection to enhance rural health research.
Parlier, Anna Beth; Galvin, Shelley L; Thach, Sarah; Kruidenier, David; Fagan, Ernest Blake
2018-01-01
To examine the literature documenting successes in recruiting and retaining rural primary care physicians. The authors conducted a narrative review of literature on individual, educational, and professional characteristics and experiences that lead to recruitment and retention of rural primary care physicians. In May 2016, they searched MEDLINE, PubMed, CINAHL, ERIC, Web of Science, Google Scholar, the Grey Literature Report, and reference lists of included studies for literature published in or after 1990 in the United States, Canada, or Australia. The authors identified 83 articles meeting inclusion criteria. They synthesized results and developed a theoretical model that proposes how the findings interact and influence rural recruitment and retention. The authors' proposed theoretical model suggests factors interact across multiple dimensions to facilitate the development of a rural physician identity. Rural upbringing, personal attributes, positive rural exposure, preparation for rural life and medicine, partner receptivity to rural living, financial incentives, integration into rural communities, and good work-life balance influence recruitment and retention. However, attending medical schools and/or residencies with a rural emphasis and participating in rural training may reflect, rather than produce, intention for rural practice. Many factors enhance rural physician identity development and influence whether physicians enter, remain in, and thrive in rural practice. To help trainees and young physicians develop the professional identity of a rural physician, multifactorial medical training approaches aimed at encouraging long-term rural practice should focus on rural-specific clinical and nonclinical competencies while providing trainees with positive rural experiences.
Rural Policies for the 1990s. Rural Studies Series.
ERIC Educational Resources Information Center
Flora, Cornelia B., Ed.; Christenson, James A., Ed.
Written by some of the foremost experts on rural America, this book focuses on policy-relevant research on the problems of rural areas. In each chapter, rural policy needs are identified by examining the flow of events and rural sociology of the 1980s. Chapters are: (1) "Critical Times for Rural America: The Challenge for Rural Policy in the…
Financial Performance of Rural Medicare ACOs.
Nattinger, Matthew C; Mueller, Keith; Ullrich, Fred; Zhu, Xi
2018-12-01
The Centers for Medicare & Medicaid Services (CMS) has facilitated the development of Medicare accountable care organizations (ACOs), mostly through the Medicare Shared Savings Program (MSSP). To inform the operation of the Center for Medicare & Medicaid Innovation's (CMMI) ACO programs, we assess the financial performance of rural ACOs based on different levels of rural presence. We used the 2014 performance data for Medicare ACOs to examine the financial performance of rural ACOs with different levels of rural presence: exclusively rural, mostly rural, and mixed rural/metropolitan. Of the ACOs reporting performance data, we identified 97 ACOs with a measurable rural presence. We found that successful rural ACO financial performance is associated with the ACO's organizational type (eg, physician-based) and that 8 of the 11 rural ACOs participating in the Advanced Payment Program (APP) garnered savings for Medicare. Unlike previous work, we did not find an association between ACO size or experience and rural ACO financial performance. Our findings suggest that rural ACO financial success is likely associated with factors unique to rural environments. Given the emphasis CMS has placed on rural ACO development, further research to identify these factors is warranted. © 2016 National Rural Health Association.
33 CFR 80.1118 - Marina Del Rey, CA.
Code of Federal Regulations, 2010 CFR
2010-07-01
... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1118 Marina Del Rey, CA. (a) A line drawn from Marina Del Rey Breakwater South Light 1 to Marina Del Rey Light 4. (b) A line drawn from Marina Del Rey... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Marina Del Rey, CA. 80.1118...
33 CFR 80.1118 - Marina Del Rey, CA.
Code of Federal Regulations, 2012 CFR
2012-07-01
... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1118 Marina Del Rey, CA. (a) A line drawn from Marina Del Rey Breakwater South Light 1 to Marina Del Rey Light 4. (b) A line drawn from Marina Del Rey... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Marina Del Rey, CA. 80.1118...
33 CFR 80.1118 - Marina Del Rey, CA.
Code of Federal Regulations, 2013 CFR
2013-07-01
... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1118 Marina Del Rey, CA. (a) A line drawn from Marina Del Rey Breakwater South Light 1 to Marina Del Rey Light 4. (b) A line drawn from Marina Del Rey... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Marina Del Rey, CA. 80.1118...
33 CFR 80.1118 - Marina Del Rey, CA.
Code of Federal Regulations, 2011 CFR
2011-07-01
... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1118 Marina Del Rey, CA. (a) A line drawn from Marina Del Rey Breakwater South Light 1 to Marina Del Rey Light 4. (b) A line drawn from Marina Del Rey... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Marina Del Rey, CA. 80.1118...
33 CFR 80.1118 - Marina Del Rey, CA.
Code of Federal Regulations, 2014 CFR
2014-07-01
... NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1118 Marina Del Rey, CA. (a) A line drawn from Marina Del Rey Breakwater South Light 1 to Marina Del Rey Light 4. (b) A line drawn from Marina Del Rey... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Marina Del Rey, CA. 80.1118...
NASA Astrophysics Data System (ADS)
Zubari, Waleed K.
Over-ion of the Dammam aquifer, the principal aquifer in Bahrain, by the agricultural and domestic sectors, has led to its salinization by adjacent brackish and saline water bodies. A hydrochemical study identified the locations of the sources of aquifer salinization and delineated their areas of influence. The investigation indicates that the aquifer water quality is significantly modified as groundwater flows from the northwestern parts of Bahrain, where the aquifer receives its water by lateral underflow from eastern Saudi Arabia, to the southern and southeastern parts. Four types of salinization of the aquifer are identified: brackish-water up-flow from the underlying brackish-water zones in north-central, western, and eastern regions; seawater intrusion in the eastern region; intrusion of sabkha water in the southwestern region; and irrigation return flow in a local area in the western region. Four alternatives for the management of groundwater quality that are available to the water authorities in Bahrain are discussed and their priority areas are proposed, based on the type and extent of each salinization source, in addition to groundwater use in that area. The effectiveness of the proposed management options in controlling the degradation of water quality in the Dammam aquifer should be evaluated using simulation modeling. Résumé La surexploitation de l'aquifère de Damman, principal aquifère de Bahreïn, du fait des besoins agricoles et domestiques, a conduit à sa salinisation à partir d'eaux voisines saumâtres et salées. Une étude hydrochimique a identifié les origines de la salinisation de l'aquifère et a délimité leurs zones d'influence. Les recherches montrent que la qualité de l'eau souterraine est modifiée de façon significative pour les écoulements souterrains dirigés vers les secteurs sud et sud-est et provenant de la région nord-ouest de Bahreïn, là où l'aquifère est alimenté latéralement à partir de l'Arabie Saoudite orientale. Quatre types de salinisation de l'eau souterraine ont été identifiés : une drainance verticale en provenance d'eaux saumâtres sous-jacentes dans les régions nord-centrales, ouest et est, une intrusion marine dans la région est, une intrusion d'eau de sebkha dans la région sud-ouest, et le retour d'irrigation dans un secteur localisé de la région sud-ouest. Quatre démarches alternatives de gestion de la qualité des eaux souterraines, acceptables par les services chargés de l'eau à Bahreïn, sont discutées et des zones d'action prioritaire sont proposées, selon le type et l'étendue de chacune des sources de salinisation et en fonction des usages de les eaux souterraines dans chaque secteur. L'efficacité des options de gestion proposées pour le contrôle de la dégradation de la qualité de l'aquifère de Damman devrait être ensuite évaluée au moyen d'un modèle de simulation. Resumen El acuífero de Damman, el más importante de Bahrein, se explota para usos agrícolas y domésticos. La sobreexplotación del mismo ha provocado su salinización por cuerpos de agua salada y salobre cercanos. Un estudio hidroquímico identificó las fuentes de salinización y ayudó a dibujar sus áreas de influencia. La calidad del agua subterránea se modifica significativamente en la dirección del flujo, desde el noroeste del país, donde las entradas son laterales y procedentes de Arabia Saudí, hacia el sur y el sudeste. Se han identificado cuatro tipos de salinización: flujo ascendente de agua salobre en las regiones norte-central, este y oeste; intrusión de agua marina en la región este; intrusión de agua salobre al sudoeste y, finalmente, retorno de riego en un área local de la región oeste. Se discuten cuatro alternativas para la gestión del agua y se proponen áreas prioritarias basadas en el tipo y la extensión de cada fuente de salinización y en los usos de agua subterránea en cada zona. La efectividad de las opciones de gestión propuestas para controlar la degradación de la calidad del agua en el acuífero Damman deberá evaluarse mediante simulaciones realizadas con un modelo numérico
Physical activity and overweight among adolescents on the Texas-Mexico border
Pérez, Adriana; Reininger, Belinda M.; Flores, Maria Isabel Aguirre; Sanderson, Maureen; Roberts, Robert E.
2006-01-01
Objective To investigate differences in associations between physical activity and overweight for students in two adjacent areas on the border between Mexico and the United States of America: students in the city of Matamoros, Mexico, and Mexican-American students in the Lower Rio Grande Valley (LRGV) area of southern Texas. Since the extremely high prevalence of overweight among Mexican-American adolescents is well-recognized, we wanted to determine whether overweight has become a problem among Mexican adolescents. Methods Students from 6 schools (n = 669), representing 12% of the ninth-grade students in Matamoros during 2002-2003, and students from 13 high schools (n = 4 736), representing 22% of the ninth-grade students in the LRGV during 2000-2001, completed questionnaires. Polytomous logistic regression was performed to estimate the risk of being at risk of overweight (≥85th percentile to <95th percentile of body mass index (BMI) for age and sex) and the risk of being overweight (≥95th percentile of BMI-for-age and sex) versus normal weight associated with measures of physical activity. For simplicity normal weight includes underweight. Results A higher percentage of adolescents in the LRGV were at risk of overweight (17.2%) in comparison with adolescents from Matamoros (14.8%). The percentages of LRGV and Matamoros adolescents who were overweight were identical (16.9%). LRGV adolescent boys (OR = 0.87, 95% CI = 0.77-0.98) who participated in team sports were less likely to be at or above the 85th percentile of BMI-for-age and sex. Although of borderline significance, Matamoros and LRGV adolescent boys who participated in physical education classes were less likely to be at risk of overweight. Neither in Matamoros nor LRGV students were any of the various physical activity categories or levels associated with being at risk of overweight or being overweight. Conclusions Nearly one-third of the students in both Matamoros and the LRGV are at risk of overweight and are overweight. Implementation of interventions on healthful dietary choices and participation in physical education classes and sports teams are essential for reducing the extremely high prevalence of overweight among students on both sides of the Texas/Mexico border. ABSTRACT. Spanish. Objetivo: Investigar si hay diferencias en las asociaciones entre la actividad física y el sobrepeso observadas en estudiantes de dos zonas colindantes en la frontera mexicanoestadounidense: estudiantes de la ciudad de Matamoros, México, y estudiantes mexicanoestadounidenses del valle a lo largo de la desembocadura del Río Bravo (VRB) en la parte sur del estado de Texas. Dada la consabida prevalencia extremadamente alta de sobrepeso en adolescentes mexicanoestadounidenses, los autores queríamos determinar si el sobrepeso también se ha convertido en un problema entre adolescentes mexicanos. Métodos: Estudiantes de 6 escuelas (n = 653), que comprenden 11% de los estudiantes de noveno grado en Matamoros durante 2002–2003, y estudiantes de 13 bachilleratos (n = 4 736), que comprenden 22% de los estudiantes de noveno grado del VRB durante 2000–2001, contestaron cuestionarios. Se llevó a cabo una regresión logística politómica a fin de calcular el riesgo de estar en riesgo de tener sobrepeso (≥85.° percentil a <95.° percentil de índice de masa corporal (IMC) para la edad y el sexo) y el riesgo de tener sobrepeso (≥95.° percentil de índice de masa corporal (IMC) para la edad y el sexo), frente a un peso normal, que se asociaban con distintos grados de actividad física. En aras de la sencillez, en la clasificación del peso normal también se abarcó la insuficiencia de peso. Resultados: Un mayor porcentaje de adolescentes estaban en riesgo de sufrir sobrepeso en el VRB (17%) que en Matamoros (15%). Los porcentajes de adolescentes de VRB y de Matamoros que tenían sobrepeso fueron idénticos (17%). Los varones adolescentes en el VRB (razón de posibilidades [RP] = 0,87; IC95% = 0,77 a 0,98) que participaron en deportes en equipo tuvieron una menor probabilidad de estar en riesgo de tener sobrepeso. No se encontraron asociaciones entre ningunas de las demás categorías de actividad física por un lado, y estar en riesgo de sufrir sobrepeso o tener sobrepeso por el otro, ni en estudiantes de Matamoros ni en los del VRB. Conclusiones: Casi una tercera parte de los estudiantes tanto en Matamoros como en el VRB está en riesgo de tener sobrepeso o tiene sobrepeso. La puesta en práctica de intervenciones para fomentar hábitos alimentarios sanos y la participación en clases de educación física y en deportes en equipo es una medida esencial para reducir la prevalencia extremadamente alta de sobrepeso observada en estudiantes a ambos lados de la frontera entre México y Estados Unidos. PMID:16723065
Chile Earthquake: U.S. and International Response
2010-03-11
5 United Nations Office for the Coordination of Humanitarian Affairs, “Chile Earthquake: Situation Report #2,” March 1, 2010; Gobierno de Chile...U.S. Department of State, March 2, 2010. 6 “Bachelet decreta primer Estado de Catástrofe desde terremoto de 1985,” El Mercurio (Chile), March 1...2010; “Amplían toque de queda en zonas más afectadas por terremoto en Chile,” Agence France Presse, March 1, 2010; “160 detained, one killed during
Follicular growth and atresia in the mouse
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oakberg, E. F.
1978-01-01
Follicles were classified on the basis of number of layers of follicle cells, presence and degree of development of the zona pellucida, and presence of an antrum. Formation of an antrum in follicles with less than 7-8 cell layers and/or presence of necrotic cells was considered indicative of degeneration. When classified in this manner, the data suggest that follicles and their contained oocytes are committed to either normal development or atresia by the time a third layer of granulosa cells is formed.
Lee, Yin Huey; Barnard, Amanda; Owen, Cathy
2011-01-01
Rural health workforce issues are a priority area for the Australian Government and substantial funding has been provided for rural education programs to address health workforce disparities across Australia's rural and remote communities. The Australian Government established a Rural Health Strategy in 2001 and as a result there are now 14 rural clinical schools in Australia. The 2008 Urbis Report highlighted the lack of research on rural programs and workforce outcomes, essential to ensuring that educational efforts, resources and funding are being concentrated appropriately. This study examined the Australian National University (ANU) Medical School's 4 year rural program to identify the impact of elective and compulsory program components on student intentions to practice in a rural and remote location post-graduation. The study also explores factors that affect student decisions to apply for year-long rural placements. METHODS; ANU Medical School's graduating cohort of 2008 fourth year medical students completed an anonymous and voluntary online survey questionnaire. Survey sections included student demographics, compulsory and elective components of the ANU rural program, and an overall evaluation of the ANU rural curriculum. The survey contained a mixture of forced-answer questions and open-ended commentary. Quantitative data were analyzed for descriptive and frequency statistics using EpiInfo V3.5.1 (http://wwwn.cdc.gov/epiinfo/). Qualitative data were reviewed and consistent themes among responses extracted. In total, 40 students from a cohort of 88 (45%) responded, with 26 respondents (65%) indicating that at medical school commencement they considered working in a rural or remote area. At the end of their medical education, 33 respondents (82%) indicated their intention to spend some time in their careers working in a rural or remote area. Students from non-rural backgrounds had greater positive change in their intentions to practice rurally as a direct effect of ANU rural programs when compared with students from rural backgrounds. More than 70% of students believed the amount of rural focus in the curriculum was correct, 75% believed that they will be better medical practitioners because of the program, and 85% found the curriculum was delivered effectively. Students who undertook elective rural programs such as a year-long rural placement were more likely to have future rural career intentions when compared with students undertaking compulsory rural components. Compulsory components, however, had a strong influence on students applying for elective programs. Regarding application for the year-long rural placement, students reported clinical exposure was the most encouraging factor, and time away from family and friends, and lack of spousal and family support were the most discouraging factors. Rural programs at the ANU, and medical school exposure to rural health experiences is important in influencing students' perceptions of a career in rural and remote health. This study provides evidence that both compulsory and elective components contribute to a successful holistic rural program which nurtures the rural interest of all students. Overall, students at the ANU medical school were satisfied with the rural curriculum. The results confirm that there is difficulty in recruiting students with family commitments into year-long rural placement programs, despite incentives. Those students who select long-term rural study for reasons other than an interest in a career in rural health end the program with positive rural intentions.
8th Argentinean Bioengineering Society Conference (SABI 2011) and 7th Clinical Engineering Meeting
NASA Astrophysics Data System (ADS)
Meschino, Gustavo Javier; Ballarin, Virginia L.
2011-12-01
In September 2011, the Eighteenth Edition of the Argentinean Bioengineering Society Conference (SABI 2011) and Seventh Clinical Engineering Meeting were held in Mar del Plata, Argetina. The Mar del Plata SABI Regional and the School of Engineering of the Universidad Nacional de Mar del Plata invited All bioengineers, engineers, physicists, mathematicians, biologists, physicians and health professionals working in the field of Bioengineering to participate in this event. The overall objectives of the Conference were: To provide discussion of scientific research results in Bioengineering and Clinical Engineering. To promote technological development experiences. To strengthen the institutional and scientific communication links in the area of Bioengineering, mainly between Universities of Latin America. To encourage students, teachers, researchers and professionals to establish exchanges of experiences and knowledge. To provide biomedical engineering technology solutions to the society and contributing ideas for low cost care. Conference photograph Conference photograph Conference photograph Conference photograph EXECUTIVE COMMITTEE SABI 2011 Chair Dra Virginia L Ballarin Universidad Nacional de Mar del Plata Co-Chair Dra Teresita R Cuadrado Universidad Nacional de Mar del Plata - CONICET Local Comittee Dr Gustavo Abraham Universidad Nacional de Mar del Plata - CONICET Dra Josefina Ballarre Universidad Nacional de Mar del Plata - CONICET Dr Eduardo Blotta Universidad Nacional de Mar del Plata Dra Agustina Bouchet Universidad Nacional de Mar del Plata Dr Marcel Brun Universidad Nacional de Mar del Plata Dra Silvia Ceré Universidad Nacional de Mar del Plata - CONICET Dra Mariela Azul Gonzalez Universidad Nacional de Mar del Plata - CONICET Dra Lucia Isabel Passoni Universidad Nacional de Mar del Plata Dr Juan Ignacio Pastore Universidad Nacional de Mar del Plata - CONICET Dra Adriana Scandurra Universidad Nacional de Mar del Plata SCIENTIFIC ADVISORY COMMITTEE President Dr Gustavo Meschino Universidad Nacional de Mar del Plata Comittee Dr Gustavo Abraham Universidad Nacional de Mar del Plata - CONICET Mg Rubén Acevedo Universidad Nacional de Entre Ríos Ing Pablo Agüero Universidad Nacional de Mar del Plata Ing Mariela Ambrustolo Universidad Nacional de Mar del Plata Dr Ricardo Armentano Universidad Favaloro Dra Virginia L Ballarin Universidad Nacional de Mar del Plata Dra Josefina Ballarre Universidad Nacional de Mar del Plata - CONICET Dr Eduardo Blotta Universidad Nacional de Mar del Plata Ing Marco Benalcázar Universidad Nacional de Mar del Plata Mg Freddy Geovanny Benalcázar Palacios Escuela Superior Politécnica de Chimborazo, Ecuador Dr Roberto Boeri Universidad Nacional de Mar del Plata - CONICET - INTEMA Dra Agustina Bouchet Universidad Nacional de Mar del Plata Dr Ariel Braidot Universidad Nacional de Entre Ríos Dr Marcel Brun Universidad Nacional de Mar del Plata Dra Silvia Ceré Universidad Nacional de Mar del Plata - CONICET Ing Fernando Clara Universidad Nacional de Mar del Plata Dr Raúl Correa Prado Universidad Nacional de San Juan Bioing Pablo Cortez Universidad Nacional de Mar del Plata Dra Teresita R Cuadrado Universidad Nacional de Mar del Plata - CONICET Ing Eduardo De Forteza Universidad Favaloro Dra Mariana Del Fresno Universidad Nacional del Centro de la Provincia de Buenos Aires Dr Martín Diaz Informática Médica Hospital Aleman de Buenos Aires - GIBBA Ing Julio César Doumecq Universidad Nacional de Mar del Plata Mg Ana María Echenique Universidad Nacional de San Juan Bioing Pedro Escobar Universidad Nacional del Centro, Olavarría, Pcia de Buenos Aires Dr Fernando Daniel Farfán Universidad Nacional de Tucumán Dr Carmelo Felice Universidad Nacional de Tucumán - CONICET Dr Elmer Fernández Universidad Católica de Córdoba - CONICET Ing José Flores Universidad Nacional de Entre Ríos Dr Arturo Gayoso Universidad Nacional de Mar del Plata Dra Bioing Agustina Garcés Universidad Nacional de San Juan ¬- CONICET Bioing Luciano Gentile Universidad Favaloro Mg María Eugenia Gómez Universidad Nacional de San Juan Dr Claudio González Universidad Nacional de Mar del Plata Mg Esteban González Universidad Nacional de Mar del Plata Dra Mariela A Gonzalez Universidad Nacional de Mar del Plata - CONICET Dr Juan Pablo Graffigna Universidad Nacional de San Juan Dra Myriam Herrera Universidad Nacional de Tucumán - CONICET Dr Roberto Hidalgo Universidad Nacional de Mar del Plata Dr Roberto Isoardi Fundación Escuela de Medicina Nuclear de Mendoza - CNEA Dra Susana Jerez Universidad Nacional de Tucumán Dr Eric Laciar Universidad Nacional de San Juan - CONICET Bioing Roberto Leonarduzzi Universidad Nacional de Entre Ríos Mg Norberto Lerendegui Instituto Tecnológico de Buenos Aires Dra Natalia López Universidad Nacional de San Juan - CONICET Dra Rossana Madrid Universidad Nacional de Tucuman - CONICET Ing Florencia Montini Ballarin Universidad Nacional de Mar del Plata - CONICET Dra Emilce Moler Universidad Nacional de Mar del Plata Dr Jorge Castiñieira Moreira Universidad Nacional de Mar del Plata Dr Silvia Murialdo Universidad Nacional de Mar del Plata - CIC Dr Juan Manuel Olivera Universidad Nacional de Tucumán Dra Lucia Isabel Passoni Universidad Nacional de Mar del Plata Dr Juan Ignacio Pastore Universidad Nacional de Mar del Plata - CONICET Dra María Elisa Pérez Universidad Nacional de San Juan Mg Franco M Pessana Universidad Favaloro Dr Julio Politti Universidad Nacional de Tucumán Dr Marcelo Risk Universidad Nacional de Buenos Aires - CONICET Ing Raúl Rivera Universidad Nacional de Mar del Plata Mg Luis Rocha Universidad Nacional de Tucumán - SIPROSA Dra Silvia Rodrigo Universidad Nacional de San Juan Dra Viviana Rotger Universidad Nacional de Tucumán Dr Leonardo Rufiner Universidad Nacional de Entre Rios - CONICET Dra Estela Ruiz Universidad Nacional de Tucumán Dr Martín Santiago Universidad Nacional del Centro de la Provincia de Buenos Aires Dra Adriana Scandurra Universidad Nacional de Mar del Plata Ing Graciela Secreto Universidad Favaloro Mg Pablo Solarz Universidad Nacional de Tucumán Mg Carolina Tabernig Universidad Nacional de Entre Ríos Ing Ricardo Taborda Universidad Nacional de Córdoba Dra María Eugenia Torres Universidad Nacional de Entre Ríos - CONICET Ing Juan Carlos Tulli Universidad Nacional de Mar del Plata Dr Gerardo Tusman Hospital Privado de Comunidad, Mar del Plata Dr Santiago Urquiza Universidad Nacional de Mar del Plata Mg Andrés Valdez Universidad Nacional de San Juan Dr Máximo Valentinuzzi INSIBIO - CONICET - Universidad Nacional de Tucumán
7 CFR 1951.218 - Use of Rural Development loans and grants for other purposes.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE SERVICE, RURAL UTILITIES SERVICE, AND FARM SERVICE... Servicing of Community and Direct Business Programs Loans and Grants § 1951.218 Use of Rural Development... the Administrator of the Rural Housing Service or Rural Business-Cooperative Service that has the...
Malatzky, Christina; Bourke, Lisa
2018-05-25
To examine the effects of dominant knowledge in rural health, including how they shape issues central to rural health. In particular, this article examines the roles of: (i) deficit knowledge of rural health workforce; (ii) dominant portrayals of generalism; and (iii) perceptions of inferiority about rural communities in maintaining health disparities between rural- and metropolitan-based Australians. A Foucauldian framework is applied to literature, evidence, case studies and key messages in rural health. Three scenarios are used to provide practical examples of specific knowledge that is prioritised or marginalised. The analysis of three areas in rural health identifies how deficit knowledge is privileged despite it undermining the purpose of rural health. First, deficit knowledge highlights the workforce shortage rather than the type of work in rural practice or the oversupply of workforce in metropolitan areas. Second, the construction of generalist practice as less skilled and more monotonous undermines other knowledge that it is diverse and challenging. Third, dominant negative stereotypes of rural communities discourage rural careers and highlight undesirable aspects of rural practice. The privileging of deficit knowledge pertaining to rural health workforce, broader dominant discourses of generalism and the nature of rural Australian communities reproduces many of the key challenges in rural health today, including persisting health disparities between rural- and metropolitan-based Australians. To disrupt the operations of power that highlight deficit knowledge and undermine other knowledge, we need to change the way in which rural health is currently constructed and understood. © 2018 National Rural Health Alliance Ltd.
Mitzelfelt, Katie A.; Limphong, Pattraranee; Choi, Melinda J.; Kondrat, Frances D. L.; Lai, Shuping; Kolander, Kurt D.; Kwok, Wai-Meng; Dai, Qiang; Grzybowski, Michael N.; Zhang, Huali; Taylor, Graydon M.; Lui, Qiang; Thao, Mai T.; Hudson, Judith A.; Barresi, Rita; Bushby, Kate; Jungbluth, Heinz; Wraige, Elizabeth; Geurts, Aron M.; Benesch, Justin L. P.; Riedel, Michael; Christians, Elisabeth S.; Minella, Alex C.; Benjamin, Ivor J.
2016-01-01
Mutations of HSPB5 (also known as CRYAB or αB-crystallin), a bona fide heat shock protein and molecular chaperone encoded by the HSPB5 (crystallin, alpha B) gene, are linked to multisystem disorders featuring variable combinations of cataracts, cardiomyopathy, and skeletal myopathy. This study aimed to investigate the pathological mechanisms involved in an early-onset myofibrillar myopathy manifesting in a child harboring a homozygous recessive mutation in HSPB5, 343delT. To study HSPB5 343delT protein dynamics, we utilize model cell culture systems including induced pluripotent stem cells derived from the 343delT patient (343delT/343delT) along with isogenic, heterozygous, gene-corrected control cells (WT KI/343delT) and BHK21 cells, a cell line lacking endogenous HSPB5 expression. 343delT/343delT and WT KI/343delT-induced pluripotent stem cell-derived skeletal myotubes and cardiomyocytes did not express detectable levels of 343delT protein, contributable to the extreme insolubility of the mutant protein. Overexpression of HSPB5 343delT resulted in insoluble mutant protein aggregates and induction of a cellular stress response. Co-expression of 343delT with WT prevented visible aggregation of 343delT and improved its solubility. Additionally, in vitro refolding of 343delT in the presence of WT rescued its solubility. We demonstrate an interaction between WT and 343delT both in vitro and within cells. These data support a loss-of-function model for the myopathy observed in the patient because the insoluble mutant would be unavailable to perform normal functions of HSPB5, although additional gain-of-function effects of the mutant protein cannot be excluded. Additionally, our data highlight the solubilization of 343delT by WT, concordant with the recessive inheritance of the disease and absence of symptoms in carrier individuals. PMID:27226619
Joining Rural Development Theory and Rural Education Practice.
ERIC Educational Resources Information Center
Hammer, Patricia Cahape
Karl N. Stauber proposes three goals for rural development policy: helping the rural middle class survive, reducing concentrated rural poverty, and sustaining and improving the quality of the natural environment. In contrast to other visions, he advises policy that focuses on rural places rather than rural economic sectors such as agriculture,…
Defining and Describing Rural: Implications for Rural Special Education Research and Policy
ERIC Educational Resources Information Center
Hawley, Leslie R.; Koziol, Natalie A.; Bovaird, James A.; McCormick, Carina M.; Welch, Greg W.; Arthur, Ann M.; Bash, Kirstie
2016-01-01
A critical aspect of rural research is carefully defining and describing the rural context. This is particularly important in rural special education research because different definitions of rural may influence resource allocation, grant funding eligibility, and/or research findings. In order to highlight the importance of operationalizing rural,…
Agriculture and Rurality: Beginning the "Final Separation"?
ERIC Educational Resources Information Center
Friedland, William H.
2002-01-01
When is a farm a farm? When is rural rural? Has the issue of the rural-urban continuum returned? Decades ago rural sociology worked itself into two blind alleys: rural-urban differences and attempts to define the rural-urban fringe. Although these conceptual problems eventually were exhausted, recent developments in California raise the…
Cohen, Steven A; Cook, Sarah K; Kelley, Lauren; Foutz, Julia D; Sando, Trisha A
2017-04-01
Obesity affects over one-third of older adults in the United States. Both aging and obesity contribute to an increased risk for chronic disease, early mortality, and additional health care utilization. Obesity rates are higher in rural areas than in urban areas, although findings are mixed. The objectives of this study are to assess potential nonlinearity in the association between rurality and obesity, and to evaluate the potential for socioeconomic status and geographic area to moderate the associations between rurality and obesity. Using a representative sample of adults aged 65 and above from the Behavioral Risk Factor Surveillance System, obesity (BMI ≥ 30 kg/m 2 ) was modeled against the primary exposure of rural-urban status, as measured by the Index of Relative Rurality. Binary logistic regression models were used to estimate the odds of obesity by rurality both as a continuous variable and by decile of rurality. Models were then stratified by per-capita income and state to assess potential moderation by these factors. The prevalence of obesity in older adults was highest in intermediate rurality areas (OR in rurality decile #5 1.134, 95% CI: 1.086-1.184) and lowest in the most rural and most urban areas. Obesity was highest in low- and middle-income areas, regardless of rural-urban status. In high-income areas, obesity among older adults was highest in areas of intermediate rurality and lowest in the most rural areas (OR 0.726, 95% CI: 0.606-0.870) and more urban areas, showing a J-shaped association. There were substantial differences in the associations between rurality and obesity in older adults among states. Associations between rurality and obesity varied by degree of rurality, socioeconomic status, and geography. Therefore, traditional "one-size-fits-all" approaches to reducing rural-urban health disparities in older adults may be more effective if tailored to the area-specific rural-urban gradients in health. © 2016 National Rural Health Association.
Medicinal ethnobotany in Huacareta (Chuquisaca, Bolivia)
2012-01-01
Background The aim of this study was to document the types of diseases treated by the use of medicinal plants, their main applications and also to have a report of the major diseases treated at the Hospital of San Pablo de Huacareta (Chuquisaca Bolivia). Methods We conducted semi-structured interviews on the use medicinal plants with 10 local informants, and categorized the kinds of diseases treated by traditional medicine. We obtained reports of cases treated at the Hospital of Huacareta in order to compare the use frequency of traditional medicine and allopathic medicine for the treatment of recurrent diseases in the area. Results Our survey identified 258 traditional medicine uses, spanning a total of 13 diseases categories and including 91 native and exotic plant species and one unidentified sample plant type. Gastrointestinal disorders (55%) were most frequently treated with medicinal plants, followed by afflictions of the musculoskeletal system (25%) and dermatological disorders (24%). Hospital information indicates that the most common diseases are acute respiratory infections (47%) and acute diarrheal diseases (37%). The herbal remedies were mostly used in the form of teas and decoctions. The informants used mainly native plant species, although exotic species has been introduced to the pharmacopoeia. Conclusions The treatment of gastrointestinal disorders is the primary objective of the medical ethnobotany of the inhabitants of Huacareta, while respiratory system diseases are mostly treated in the hospital. Looking at the data from the Hospital records we can infer that gastrointestinal disorders are among the most common diseases in the study area. For most respondents, traditional medicine is a reliable choice for the care of their illnesses. However, the preference of the population for either traditional medicine or allopathic medicine needs to be clarified in future comparative studies to obtain more convincing results. The results presented can be used as a base for subsequent work related to traditional medicine and its contribution to allopathic medicine in San Pablo de Huacareta. Resumen Introducción El objetivo del presente estudio fue documentar los tipos de enfermedades tratadas mediante el uso de plantas medicinales, sus aplicaciones principales y también tener un reporte de las enfermedades mayormente atendidas en el Hospital de San Pablo de Huacareta (Chuquisaca, Bolivia). Métodos Se realizaron encuestas semiestructuradas a 10 informantes locales anotando los usos atribuidos a sus plantas medicinales, se agruparon las plantas por categorías de enfermedades tratadas en la medicina tradicional. Se obtuvieron reportes de casos tratados en el Hospital de Huacareta para poder relacionar el tratamiento de enfermedades recurrentes en la zona entre la medicina tradicional y la medicina occidental. Resultados Se reportaron 91 especies nativas y exóticas, además de un espécimen indeterminado exótico que intervienen en un total de 258 aplicaciones medicinales, las cuales son empleadas en un total de 13 categorías de enfermedades. Los desórdenes gastrointestinales (55%) son mayormente tratados mediante plantas medicinales, seguidas de las afecciones al sistema esqueleto-muscular (25%) y enfermedades dermatológicas (24%). La información del Hospital indica que las enfermedades más frecuentes son Infecciones Respiratorias Agudas (47%) y Enfermedades Diarreicas Agudas (37%). Los remedios vegetales se emplean en forma de infusiones y cocciones principalmente. Se emplean mayormente plantas nativas, también se introdujo en la farmacopea médica el uso de plantas exóticas al lugar. Conclusiones El tratamiento de trastornos gastrointestinales constituye el objetivo primordial de la etnobotánica médica de los habitantes de Huacareta, las enfermedades del sistema respiratorio, son mayormente tratadas en el Hospital. Observando los datos del libro de consultas del Hospital, se puede inferir que los desórdenes gastrointestinales están entre las enfermedades más frecuentes en el área estudiada. Para la mayoría de los entrevistados, la medicina tradicional es una opción confiable para la atención de sus enfermedades. Sin embargo, la preferencia de los habitantes entre la medicina tradicional y la medicina alopática podría ser clarificada a partir de futuros estudios comparativos que permitan obtener resultados más convincentes. Los resultados expuestos pueden ser usados como una base de datos para posteriores trabajos relacionados a la medicina tradicional y su contribución con la medicina alopática en San Pablo de Huacareta. PMID:22856877
A comparison of the vending environment among three rural subtypes of secondary schools.
Kehm, Rebecca; Davey, Cynthia S; Kubik, Martha Y; Nanney, Marilyn S
2018-01-01
The purpose of this study was to further explore the rural school food environment. This study assessed trends in prevalence of vending machines and vending items within and between Minnesota schools located in 3 rural subtypes: town/rural fringe, town/rural distant, and remote rural. Generalized estimating equation models were employed to analyze data from the 2006 through 2012 School Health Profiles Principal's Surveys (Profiles). All 3 rural subtypes had a statistically significant decrease in the prevalence of low nutrient energy dense (LNED) vending items between 2006 and 2012, with the exception of sports drinks. However, different vending practices were observed between rural subtypes, with town/rural fringe schools providing more LNED vending options and experiencing less positive change over time compared to town/rural distant and remote rural schools. Differences in vending machine practices emerge when rural schools are subtyped.
Eidson-Ton, W Suzanne; Rainwater, Julie; Hilty, Donald; Henderson, Stuart; Hancock, Christine; Nation, Cathryn L; Nesbitt, Thomas
2016-01-01
The Association of American Medical Colleges projects an increasing shortage of physicians in rural areas. Medical schools have developed specialty track programs to improve the recruitment and retention of physicians who can serve rural populations. One such program in California includes a variety of unique elements including outreach, admissions, rural clinical experiences, focused mentorship, scholarly and leadership opportunities, and engagement with rural communities. Preliminary outcomes demonstrate that this rural track program has achieved some success in the recruitment, retention, and training of students interested in future rural practice and in the placement of students in primary care residencies. Long-term outcomes, such as graduates entering rural practice, are still unknown, but will be monitored to assess the impact and sustainability of the rural program. This article illustrates the opportunities and challenges of training medical students for rural practice and provides lessons learned to inform newly-established and long standing rural medical education programs.
Rural development and urban migration: can we keep them down on the farm?
Rhoda, R
1983-01-01
This study tests the hypothesis that rural development projects and programs reduce rural-urban migration. The author presents various factors in the social theories of migration, including those relating to origin and destination, intervening obstacles such as distance, and personal factors. 3 economic models of migration are the human capital or cost-benefit approach, the expected income model, and the intersectoral linkage model. Empirical studies of migration indicate that: 1) rural areas with high rates of out-migration tend to have high population densities or high ratios of labor to arable land, 2) distance inhibits migration, 3) rural-urban migration is positively correlated with family income level, and 4) selectivity differences in socioeconomic status between migrants and nonmigrants often are grouped into development packages which might include irrigation, new varieties of seed, subsidized credit, increased extension, and improved marketing arrangements. The migration impacts of some of these efforts are described: 1) land reform usually is expected to slow rural out-migration because it normally increases labor utilization in rural areas, but this is a limited effect, 2) migration effects of the Green Revolution technology are mainly in rural-rural migration, and 3) agricultural mechanization may stimulate rural-urban migration in the long run. Development of rural social services migh have various effects on rural-urban migration. Better rural education, which improves the chances of urban employment, will stimulate rural-urban migration, while successful rural family planning programs will have a negative effect in the long run as there will be reduced population pressure on arable land. Better rural health services might reduce the incentive for rural-urban migration as well. It is suggested that governments reconsider policies which rely on rural development to curb rural-urban migration and alleviate problems of urban poverty and underemployment.
Somers, George T; Spencer, Ryan J
2012-04-01
Do undergraduate rural clinical rotations increase the likelihood of medical students to choose a rural career once pre-existent likelihood is accounted for? A prospective, controlled quasi-experiment using self-paired scores on the SOMERS Index of rural career choice likelihood, before and after 3 years of clinical rotations in either mainly rural or mainly urban locations. Monash University medical school, Australia. Fifty-eight undergraduate-entry medical students (35% of the 2002 entry class). The SOMERS Index of rural career choice likelihood and its component indicators. There was an overall decline in SOMERS Index score (22%) and in each of its components (12-41%). Graduating students who attended rural rotations were more likely to choose a rural career on graduation (difference in SOMERS score: 24.1 (95% CI, 15.0-33.3) P<0.0001); however, at entry, students choosing rural rotations had an even greater SOMERS score (difference: 27.1 (95% CI, 18.2-36.1) P<0.0001). Self-paired pre-post reductions in likelihood were not affected by attending mainly rural or urban rotations, nor were there differences based on rural background alone or sex. While rural rotations are an important component of undergraduate medical training, it is the nature of the students choosing to study in rural locations rather than experiences during the course that is the greater influence on rural career choice. In order to improve the rural medical workforce crisis, medical schools should attract more students with pre-existent likelihood to choose a rural career. The SOMERS Index was found to be a useful tool for this quantitative analysis. © 2012 The Authors. Australian Journal of Rural Health © 2012 National Rural Health Alliance Inc.
Rural women caregivers in Canada.
Crosato, Kay E; Leipert, Beverly
2006-01-01
Informal caregiving within rural contexts in Canada is increasing. This is due in part to a number of factors related to the restructuring of the Canadian health care system, the regionalization of services to urban locations, the increased population of people 65 years and older, and the desire of this population to age within their rural homes. Most often, the informal caregiving role is assumed by rural women. Women tend to fall into the role of informal caregiver to elders because of the many societal and gender expectations and values that are present within the rural culture. The purpose of this literature review is to identify the context in which women provide care for an elder in rural Canada. Illustrating these issues will help to uncover challenges and barriers rural women face when providing care and highlight recommendations and implications for rural women caregivers and nurses employed within rural settings. Many rural women share similar caregiving experiences as urban informal caregivers, but rural women are faced with additional challenges in providing quality care for an elder. Rural women caregivers are faced with such issues as limited access to adequate and appropriate healthcare services, culturally incongruent health care, geographical distance from regionalized centers and health services, transportation challenges, and social/geographical isolation. In addition to these issues, many rural women are faced with the multiple role demands that attend being a wife, mother, caregiver and employee. The pile up of these factors leaves rural women caregivers susceptible to additional stresses and burn out, with limited resources on which to depend. Through reviewing pertinent literature, appropriate implications and recommendations can be made that may assist rural women caregivers and rural nurses. Nurses working within rural communities are in ideal settings to work collaboratively in building supportive relationships with rural women in order to promote the health and wellbeing of caregivers, as well as the elders for which they provide care. More research is needed regarding rural women and their caregiving experiences of elders. In addition, rural and remote courses and practicums should be made available to nursing students in order to encourage them and to support them in nursing careers in rural settings, thereby providing rural women caregivers with additional appropriate and consistent healthcare services. Also, governments and policy makers should consider the rural context and the challenges that are associated with providing care to an elder in a rural setting to ensure that rural women caregivers and their care recipients are well supported within their rural communities.
The influence of loan repayment on rural healthcare provider recruitment and retention in Colorado.
Renner, Daniel M; Westfall, John M; Wilroy, Lou Ann; Ginde, Adit A
2010-01-01
There is an ongoing shortage of rural healthcare providers relative to urban healthcare providers worldwide. Many strategies have been implemented to increase the distribution of rural healthcare providers, and financial incentives such as loan repayment programs have become popular means to both recruit and retain healthcare providers in rural communities. Studies detailing the effects of such programs on rural provider recruitment and retention are limited. The objective of this study was to assess the influence of loan repayment and other factors on the recruitment and retention of healthcare providers in rural Colorado, USA, and to compare the motivations and attitudes of these rural providers with their urban counterparts. A survey was sent to 122 healthcare providers who had participated in one of three loan repayment programs in Colorado between the years of 1992 and 2007: the Colorado Health Professional Loan Repayment Program; the Colorado Rural Outreach Program; and the Dental Loan Repayment Program of Colorado. Differentiation between rural and urban communities was accomplished by using the Rural Urban Commuting Area Codes developed by the University of Washington's Rural Health Research Center and Economic Research Service. Statistical analysis was performed using STATA from StataCorp. Of the 93 respondents included in the study, 57 worked in rural communities and 36 worked in urban communities during their programs. Of the rural participants, 74% were already working in or intending to work in an eligible community when they were made aware of the loan repayment program. Of those planning to work in a rural community regardless of any loan repayment option, 42% reported that the loan repayment program had an important influence on the specific community in which they chose to practice. Of the rural participants already working in a rural community, 38% reported loan repayment as being an important factor in their retention. The most important factors the rural providers cited for their recruitment were the location of the community, scope of practice, and family fit with the community. The most important factors for the urban providers were the location of the community, salary, and scope of practice. Of the rural providers, 36% attended rural high schools, while 9% of urban providers attended rural high schools. Of the rural providers who were planning on practicing in a rural area regardless of any loan repayment option, 37% had attended rural high schools. Rural participants most often left their communities because their families wanted to move, personal or professional isolation, and dissatisfaction with the medical community. Of rural participants 22% cited the desire for a higher income as an important reason to leave their communities, while the desire for a higher income was the most commonly cited reason for the urban providers. Rural retention rates were not influenced by past attendance at rural high schools or by intention to practice in a rural community regardless of loan repayment. Loan repayment programs targeting rural Colorado usually enroll providers who would have worked in a rural area regardless of loan repayment opportunities, but are likely to play a role in providers' choice of specific rural community for practice. They also appear to have a limited but important influence on rural provider retention, though financial concerns are generally less influential for non-retained rural providers than are family preferences and professional dissatisfaction.
Shannon, C Ken; Jackson, Jodie
2015-01-01
The validity of medical student projection of, and predictors for, rural practice and the association of a measure of service orientation, projected practice accessibility to the indigent, were investigated. West Virginia (WV) medical student online pre- and postrural rotation questionnaire data were collected during the time period 2001-2009. Of the 1,517 respondent students, submissions by 1,271 met the time interval criterion for inclusion in analyses. Subsequent WV licensing data were available for 461 in 2013. These 2 databases were used to assess for validity of projection of rural practice, for predictors of rural practice, and for student projected accessibility of the future practice to indigent patients. There were statistically significant associations between both pre- and postrotation projections of rural practice and subsequent rural practice. The most significant independent predictors of rural practice were student rural background, reported primary care intent, prediction of rural practice and projection of greater accessibility of the future practice to indigent patients. For scoring of practice access, there were trends for higher scoring by rural students and rural practitioners, with greater pre-post increases for those with urban hometowns. This study demonstrates the utility of medical student questionnaires for projections of numbers of future rural physicians. It suggests that students with a rural background, rural practice intent, or greater service orientation are more likely to enter rural practice. It also suggests that students, particularly those with urban hometowns, are influenced by rural rotation experiences in forecasting greater practice accessibility and in entering rural practice. © 2015 National Rural Health Association.
Rural Roots: News, Information, and Commentary from the Rural School and Community Trust, 2002.
ERIC Educational Resources Information Center
Yaunches, Alison, Ed.; Loveland, Elaina, Ed.
2002-01-01
This document contains the six issues of "Rural Roots" published bimonthly in 2002. A newsletter of the Rural School and Community Trust, "Rural Roots" provides news, information, and commentary from the Rural Trust and highlights the wide variety of place-based education work happening in rural schools and communities across…
Proyecto para la medición sistemática de seeing en CASLEO
NASA Astrophysics Data System (ADS)
Fernández Lajus, E.; Forte, J. C.
La calidad del seeing astronómico es ciertamente uno de los parámetros mas importantes que caracterizan el sitio de un observatorio. Por tanto se desea determinar si el alto valor de seeing observado con el telescopio de 2.15 m se debe a efectos internos y/o del entorno a la cupula o si se debe simplemente al seeing propio del lugar. El actual mecanismo de refrigeración del espejo primario del 2.15, parece haber mejorado notablemente la calidad del seeing. Sin embargo se hace necesario saber hasta que punto el valor del seeing puede ser mejorado. La primera etapa del proyecto consistió en la puesta a punto del telescopio emplazado para este propósito y la adquisición de las primeras medidas tentativas de seeing.
75 FR 36349 - Announcement of Rural Cooperative Development Grant Application Deadlines
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-25
... DEPARTMENT OF AGRICULTURE Rural Business-Cooperative Service Announcement of Rural Cooperative Development Grant Application Deadlines AGENCY: Rural Business-Cooperative Service, USDA. ACTION: Notice of...: Overview Federal Agency: Rural Business-Cooperative Service (RBS). Funding Opportunity Title: Rural...
Talbot, Jean A; Coburn, Andrew; Croll, Zach; Ziller, Erika
2013-06-01
The Affordable Care Act (ACA) requires Health Insurance Exchanges (HIEs) to specify network adequacy standards for the Qualified Health Plans (QHPs) they offer to consumers. This article examines rural issues surrounding network adequacy standards, and offers recommendations for crafting standards that optimize rural access. This policy analysis reviews ACA requirements for QHP network adequacy standards, considering Medicaid managed care and Medicare Advantage (MA) standards as models. We analyze the implications of stringent vs flexible access standards in terms of how choices might affect health plans' participation in rural markets and rural enrollees' access to care. Finally, we propose strategies for designing standards with the degree of flexibility most likely to benefit rural consumers. A traditional approach to safeguarding rural access is to impose strict network adequacy standards on plans in rural areas. However, if strict standards prove difficult to meet due to rural provider scarcity, they might diminish QHPs' willingness to serve rural areas. Thus, they could exacerbate rather than alleviate rural access problems. To benefit rural communities, network adequacy standards must be strong enough to provide real protections for beneficiaries, yet flexible enough to accommodate rural delivery system constraints and remain attainable for QHPs. Useful strategies to achieve this balance might include: adjusting standards according to degrees of rurality and rural utilization norms; counting midlevel clinicians toward fulfillment of patient-provider ratios; and allowing plans to ensure rural access through delivery system innovations such as telehealth. © 2013 National Rural Health Association.
ERIC Educational Resources Information Center
LaGreca, Nancy
2012-01-01
This study explores the intertextuality between Aurora Caceres's "La rosa muerta" (1914) and the novel "Del amor, del dolor y del vicio" (1898) by her ex-husband, Enrique Gomez Carrillo. Caceres strategically mentions Gomez Carrillo's novel in "La rosa muerta" to invite a reading of her work in dialogue with his. Both narratives follow the sexual…
The role of rural nurse managers in supporting new graduate nurses in rural practice.
Lea, Jackie; Cruickshank, Mary
2017-04-01
To investigate the nature and timing of support available to new graduate nurses within a rural transition to practice programme. For new graduates in rural practice successful transition is complicated by the unique role of the rural nurse, staff ratios and resources within rural environments. Little is known about the support needs of graduates working in rural health services, or who is best placed to provide support during their transition. This was a qualitative case study, using individual interviews with new graduate nurses at 3, 6 and 9 months milestones during a 12-month rural transition to practice programme plus interviews with experienced rural nurses who were employed in rural health agencies where the new graduate nurses were employed. Graduates in rural health services rely on nurse unit managers and nurse managers for feedback, support and debriefing, provision of emotional support, advocacy, openness, encouragement and protection from organisational requests and demands during the transition to rural nursing practice. Nurse managers play an important role in rural health services in the provision of support for new graduate nurses. As clinical leaders rural nurse managers and nurse unit managers, have an important role in facilitating the successful entry and retention of new graduate nurses into the rural nursing workforce. © 2016 John Wiley & Sons Ltd.
Eley, Diann S; Leung, Janni K; Campbell, Narelle; Cloninger, C Robert
2017-05-01
Resilience, coping with uncertainty and learning from mistakes are vital characteristics for all medical disciplines - particularly rural practice. Levels of coping constructs were examined in medical students with and without a rural background or an interest in rural practice. Cross-sectional surveys identified two personality profiles, and their association with levels of Tolerance of Ambiguity, Resilience, Perfectionism-High Standards and Concern over mistakes as constructs indicative of coping. Medical students (N = 797) were stratified by rural background and degree of rural interest. Mediation analysis tested the effect of personality profile on levels of the coping constructs. More (72%) rural background students had Profile 1 which was associated with higher levels of Tolerance of Ambiguity, High standards, and Resilience, but lower Concern over mistakes. Non-rural background students reporting a strong rural interest also had Profile 1 (64%) and similar levels of coping constructs. Personality profile mediated the association between rural interest and levels of coping constructs regardless of background. Having a rural background or strong rural interest are associated with a personality profile that indicates a better capacity for coping. Personality may play a part in an individual's interest in rural practice. Rural workforce initiatives through education should encourage and nurture students with a genuine interest in rural practice - regardless of background.
Yanovski, J A; Diament, A L; Sovik, K N; Nguyen, T T; Li, H; Sebring, N G; Warden, C H
2000-06-01
Little is known about genes that affect childhood body weight. The objective of this study was to examine the association between alleles of the mitochondrial uncoupling protein 2 (UCP2) gene and obesity because UCP2 may influence energy expenditure. We related UCP2 genotype to body composition and resting energy expenditure in 105 children aged 6-10 y. Overweight children and nonoverweight children of overweight parents were genotyped for a 45-base pair deletion/insertion (del/ins) in 3'-untranslated region of exon 8 and for an exon 4 C to T transition. Eighty-nine children were genotyped for the exon 8 allele: 50 children had del/del, 33 had del/ins, and 6 had ins/ins. Mean (+/-SD) body mass index (BMI; in kg/m(2)) was greater for children with del/ins (24.1 +/- 5.9) than for children with del/del (20.4 +/- 4.8; P < 0.001). BMI of ins/ins children (23.7 +/- 7.8) was not significantly different from that of del/ins children. A greater BMI in del/ins children was independent of race and sex. Body composition was also different according to UCP2 genotype. All body circumferences and skinfold thicknesses examined were significantly greater in del/ins than in del/del children. Body fat mass as determined by dual-energy X-ray absorptiometry was also greater in del/ins than in del/del children (P < 0.005). For 104 children genotyped at exon 4, no significant differences in BMI or body composition were found among the 3 exon 4 genotypes. Neither resting energy expenditure nor respiratory quotient were different according to UCP2 exon 4 or exon 8 genotype. The exon 8 ins/del polymorphism of UCP2 appears to be associated with childhood-onset obesity. The UCP2/UCP3 genetic locus may play a role in childhood body weight.
Uptake of Free HPV Vaccination among Young Women: A Comparison of Rural versus Urban Rates
ERIC Educational Resources Information Center
Crosby, Richard A.; Casey, Baretta R.; Vanderpool, Robin; Collins, Tom; Moore, Gregory R.
2011-01-01
Purpose: To contrast rates of initial HPV vaccine uptake, offered at no cost, between a rural clinic, a rural community college, and an urban college clinic and to identify rural versus urban differences in uptake of free booster doses. Methods: Young rural women attending rural clinics (n = 246), young women attending a rural community college (n…
ERIC Educational Resources Information Center
Nkambule, T.; Balfour, R. J.; Pillay, G.; Moletsane, R.
2011-01-01
Historically, rurality and rural education have been marginalised bodies of knowledge in South Africa. The post-1994 era has seen an emerging government concern to address the continuing interplay between poverty, HIV/AIDS, underdevelopment, and underachievement in schools categorised as rural. To address these concerns, scholars in South African…
77 FR 4885 - Rural Business Investment Program
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-01
...-AA80 Rural Business Investment Program AGENCY: Rural Business-Cooperative Service and Rural Utilities... several technical amendments to correct the Rural Business Investment Program (RBIP) regulation, including one to conform to the 2008 Farm Bill provision that allows a Rural Business Investment Company two...
Development Strategy for Mobilecommunications Market in Chinese Rural Area
NASA Astrophysics Data System (ADS)
Zhang, Liwei; Zhang, Yanjun; Xu, Liying; Li, Daoliang
Based on full analysis of rural mobile communication market, in order to explore mobile operators in rural areas of information services for sustainable development model, this paper presents three different aspects, including rural mobile communications market demand, the rural market for mobile communications business model and development strategies for rural mobile communications market research business. It supplies some valuable references for operators to develop rural users rapidly, develop the rural market effectively and to get access to develop a broad space.
Pruitt, Sandi L; Eberth, Jan M; Morris, E Scott; Grinsfelder, David B; Cuate, Erica L
2016-01-01
Introduction Rural residence is associated with later stage of breast cancer diagnosis in some but not all prior studies. The lack of a standardized definition of rural residence may contribute to these mixed findings. We characterize and compare multiple definitions of rural vs. non-rural residence to provide guidance regarding choice of measures and to further elucidate rural disparities in breast cancer stage at diagnosis. Methods We used Texas Cancer Registry data of 120,738 female breast cancer patients ≥50 years old diagnosed between 1995–2009. We defined rural vs. non-rural residence using 7 different measures and examined their agreement using Kappa statistics. Measures were defined at various geographic levels: county, ZIP code, census tract, and census block group. Late-stage was defined as regional or distant disease. For each measure, we tested the association of rural residence and late-stage cancer with unadjusted and adjusted logistic regression. Covariates included: age; patient race/ethnicity; diagnosis year; census block group-level mammography capacity; and census tract-level percent poverty, percent Hispanic, and percent Black. Results We found moderate to high levels of agreement between measures of rural vs. non-rural residence. For 72.9% of all patients, all 7 definitions agreed as to rural vs. non-rural residence. Overall, 6 of 7 definitions demonstrated an adverse association between rural residence and late-stage disease in unadjusted and adjusted models (Adjusted OR Range = 1.09–1.14). Discussion Our results document a clear rural disadvantage in late-stage breast cancer. We contribute to the heterogeneous literature by comparing varied measures of rural residence. We recommend use of the census tract-level Rural Urban Commuting Area Codes in future cancer outcomes research where small area data are available. PMID:27158685
Utilising a collective case study system theory mixed methods approach: a rural health example
2014-01-01
Background Insight into local health service provision in rural communities is limited in the literature. The dominant workforce focus in the rural health literature, while revealing issues of shortage of maldistribution, does not describe service provision in rural towns. Similarly aggregation of data tends to render local health service provision virtually invisible. This paper describes a methodology to explore specific aspects of rural health service provision with an initial focus on understanding rurality as it pertains to rural physiotherapy service provision. Method A system theory-case study heuristic combined with a sequential mixed methods approach to provide a framework for both quantitative and qualitative exploration across sites. Stakeholder perspectives were obtained through surveys and in depth interviews. The investigation site was a large area of one Australian state with a mix of rural, regional and remote communities. Results 39 surveys were received from 11 locations within the investigation site and 19 in depth interviews were conducted. Stakeholder perspectives of rurality and workforce numbers informed the development of six case types relevant to the exploration of rural physiotherapy service provision. Participant perspective of rurality often differed with the geographical classification of their location. The numbers of onsite colleagues and local access to health services contributed to participant perceptions of rurality. Conclusions The complexity of understanding the concept of rurality was revealed by interview participants when providing their perspectives about rural physiotherapy service provision. Dual measures, such as rurality and workforce numbers, provide more relevant differentiation of sites to explore specific services, such rural physiotherapy service provision, than single measure of rurality as defined by geographic classification. The system theory-case study heuristic supports both qualitative and quantitative exploration in rural health services research. PMID:25066241
Utilising a collective case study system theory mixed methods approach: a rural health example.
Adams, Robyn; Jones, Anne; Lefmann, Sophie; Sheppard, Lorraine
2014-07-28
Insight into local health service provision in rural communities is limited in the literature. The dominant workforce focus in the rural health literature, while revealing issues of shortage of maldistribution, does not describe service provision in rural towns. Similarly aggregation of data tends to render local health service provision virtually invisible. This paper describes a methodology to explore specific aspects of rural health service provision with an initial focus on understanding rurality as it pertains to rural physiotherapy service provision. A system theory-case study heuristic combined with a sequential mixed methods approach to provide a framework for both quantitative and qualitative exploration across sites. Stakeholder perspectives were obtained through surveys and in depth interviews. The investigation site was a large area of one Australian state with a mix of rural, regional and remote communities. 39 surveys were received from 11 locations within the investigation site and 19 in depth interviews were conducted. Stakeholder perspectives of rurality and workforce numbers informed the development of six case types relevant to the exploration of rural physiotherapy service provision. Participant perspective of rurality often differed with the geographical classification of their location. The numbers of onsite colleagues and local access to health services contributed to participant perceptions of rurality. The complexity of understanding the concept of rurality was revealed by interview participants when providing their perspectives about rural physiotherapy service provision. Dual measures, such as rurality and workforce numbers, provide more relevant differentiation of sites to explore specific services, such rural physiotherapy service provision, than single measure of rurality as defined by geographic classification. The system theory-case study heuristic supports both qualitative and quantitative exploration in rural health services research.
Maekawa, Tomoki; Hosur, Kavita; Abe, Toshiharu; Kantarci, Alpdogan; Ziogas, Athanasios; Wang, Baomei; Van Dyke, Thomas E; Chavakis, Triantafyllos; Hajishengallis, George
2015-09-16
Del-1 is an endothelial cell-secreted anti-inflammatory protein. In humans and mice, Del-1 expression is inversely related to that of IL-17, which inhibits Del-1 through hitherto unidentified mechanism(s). Here we show that IL-17 downregulates human endothelial cell expression of Del-1 by targeting a critical transcription factor, C/EBPβ. Specifically, IL-17 causes GSK-3β-dependent phosphorylation of C/EBPβ, which is associated with diminished C/EBPβ binding to the Del-1 promoter and suppressed Del-1 expression. This inhibitory action of IL-17 can be reversed at the GSK-3β level by PI3K/Akt signalling induced by D-resolvins. The biological relevance of this regulatory network is confirmed in a mouse model of inflammatory periodontitis. Intriguingly, resolvin-D1 (RvD1) confers protection against IL-17-driven periodontal bone loss in a Del-1-dependent manner, indicating an RvD1-Del-1 axis against IL-17-induced pathological inflammation. The dissection of signalling pathways regulating Del-1 expression provides potential targets to treat inflammatory diseases associated with diminished Del-1 expression, such as periodontitis and multiple sclerosis.
Grandclément, B; Ronsin, B; Morel, G
1997-03-01
Atrial natriuretic peptide (ANP) actions are mediated by highly selective and specific receptors. Three subtypes have been characterized and cloned: ANP receptor-A (or GC-A), -B (or GC-B) and -C (the so-called clearance receptor). In rat adrenal gland, the mRNA for each subtype was detected using 35S-dUTP or digoxigenin-11-dUTP specific labeled probes, and in situ hybridization at light and electron microscopic levels respectively. The three subtypes were expressed the most abundantly in the zona glomerulosa. The amount of GC-A mRNA expression, quantified using macro-autoradiography and densitometry, was higher than the amounts of GC-B mRNA and ANPR-C mRNA both in zona glomerulosa and medullary of adrenal gland. At electron microscopic level, the three subtypes of ANPR were revealed in glomerulosa cells. A noticeable signal was also present in the medullary area, especially for GC-A mRNA, in adrenaline-containing chromaffin cells. No signal was detected in noradrenaline-containing chromaffin cells. The subcellular localization of the three mRNAs is similar: in the cytoplasmic matrix and in the euchromatin of the nucleus in each cell of glomerulosa, and in the same compartments of the adrenaline-containing chromaffin cells. These data indicate that the adrenal gland is an important target tissue for ANP action both in glomerulosa cells and adrenaline-containing chromaffin cells. The mRNA expression levels were different for each ANPR subtype.
Rudraraju, Nirmala; Baltz, Jay M
2009-11-01
SummaryWe have investigated whether culture in glycine-containing medium affects subsequent glycine transport by the specific transport system, GLYT1, which is the sole glycine transporter in fertilized mouse ova. When fertilized ova were maintained for 6 h in culture with a physiological level of glycine (1 mM), subsequent transport of radiolabelled glycine was decreased by 40% compared with fertilized ova that had been maintained in glycine-free medium. Kinetic measurements showed that the apparent glycine affinity was decreased after culture with glycine (Km increased from 0.20 to 0.41 mM), but maximal transport rate was unchanged (similar Vmax of 20 and 23 fmol/fertilized ovum/min). These findings could have reflected activation of GLYT1 by prolonged substrate starvation, similar to some other amino acid transport systems. However, our findings were instead consistent with the alteration in glycine transport being due to trapping of glycine within the zona pellucida resulting in competitive transport inhibition even after ova were removed from glycine-containing media. First, even very brief exposures to glycine resulted in decreased subsequent glycine transport rates, with a maximal effect apparent within ~6 min. Second, extensive washing (at least six) reversed the effect. Third, the effect was absent when zona-free fertilized ova were used. Thus, it appears that components of the external environment of preimplantation embryos may continue to affect transport kinetics for a period even after embryos are removed from environments that contain them.
The Maturation of Oocyte Follicular Epithelium of Podarcis s. sicula Is Promoted by d-Aspartic Acid
Raucci, Franca; Di Fiore, Maria Maddalena
2010-01-01
We investigated whether the maturation of oocyte follicular epithelium of lizard is affected by d-aspartic acid (d-Asp). Our results demonstrated that d-Asp is endogenously present in the oocytes, and its distribution varies during the reproductive cycle and following intraperitoneal administration. At previtellogenesis, it is observed in the cytoplasm and nucleus of pyriform cells, in intermediate cells, in some small cells of the granulosa, in the ooplasm, and in some thecal elements. At vitellogenesis, d-Asp is localized in the proximity of the zona pellucida, in the theca, and in the ooplasm. Injected d-Asp is mainly captured by pyriform cells and ooplasm of previtellogenic oocytes, but a moderate accumulation is evident in the cytoplasm of some small granulosa cells and in the theca. d-Asp also increases the ovarian and plasmatic levels of 17β-estradiol and decreases those of testosterone. As a direct and/or indirect consequence of d-Asp, previtellogenic oocytes grow up and mature, resulting in a higher accumulation of carbohydrates in the granulosa, zona pellucida, and ooplasm, but also a reduction in the thickness of the granulosa layer and an increase of the theca stratum. Taken together, our results show that d-Asp may be related to the synchrony of reproduction, either enhancing the growth and maturation of follicular epithelium or influencing its endocrine functions. (J Histochem Cytochem 58:157–171, 2010) PMID:19826072
Santos, R R M; Cavallari, M M; Pimenta, M A S; Abreu, A G; Costa, M R; Guedes, M L
2015-06-11
Attalea vitrivir Zona (synonym Orbignya oleifera) is one of the six species of Arecaceae known as "babassu". This species is used to make cosmetics, food, and detergents due to the high concentration of oil in the seeds. It is found only in fragmented areas of southern Bahia State and northern Minas Gerais State, southeast Brazil, and this fragmentation has affected both its ecological and genetic characteristics. We evaluated the genetic diversity and population genetic structure of A. vitrivir in six areas of two different regions at the extremes of its geographical range, in order to gain a better understanding of the factors that affect the distribution and partitioning of its diversity. Nine inter simple sequence repeat (ISSR) markers amplified 74 polymorphic bands, resulting in large diversity values (Shannon diversity index, 0.37-0.47; intrapopulation genetic diversity, 0.25-0.34). Analysis of molecular variance (AMOVA) revealed considerable differentiation between sampling sites (30.03%) and regions (12.08%), although most of the diversity was observed within sampling sites (69%). Further differentiation between sampling sites was noted more in the northern region than in the southern region, highlighting the genetic connectivity between the sampling sites within Rio Pandeiros Environmental Protection Area (southern region). The identification of two distinct genetic clusters (K = 2) corresponded to the northern and southern regions, and corroborated the AMOVA results. We suggest that the northern area, outside Rio Pandeiros Environmental Protection Area, must be included in future management plans for this species.
Bedford, J Michael
2014-02-01
Therian (marsupial and eutherian) mammals have evolved a suite of novel reproductive features - seen variously in their gametes, the steps of fertilization and the male reproductive tract - whose adaptive significance remains unclear. Present evidence for the better-understood eutherian mammals suggests that the 'prime mover' in their evolution has been the character of the egg coat, with other such features being adaptations to the consequences of this. Its elastic thickness allows the zona pellucida to stretch to a variable degree and yet remain around the blastocyst during much or all of its expansion before implantation, but its character represents an unusual challenge for spermatozoa. Novel aspects of the acrosome related to this challenge enable it to maintain a relatively prolonged binding after the onset of the acrosome reaction, and the structure, shape and behaviour of the sperm head point to physical thrust as a major element of zona penetration - with the unique configuration of gamete fusion as a sequela of this strategy. In the male, such adaptations are reflected in sperm head formation in the testis and in sperm maturation in the epididymis involving at least the sperm head's structure, plasmalemma and acrosome. This complexity allied to a slow epididymal sperm transport, a relatively modest sperm production and the brief life span of mature spermatozoa kept above the cauda epididymidis could account for the evolution of the sperm storage function - a development seemingly linked, in turn, to the need for sperm capacitation and scrotal evolution.
Regulator of G-protein signaling 2 (RGS2) suppresses premature calcium release in mouse eggs
Bernhardt, Miranda L.; Lowther, Katie M.; Padilla-Banks, Elizabeth; McDonough, Caitlin E.; Lee, Katherine N.; Evsikov, Alexei V.; Uliasz, Tracy F.; Chidiac, Peter; Williams, Carmen J.; Mehlmann, Lisa M.
2015-01-01
During oocyte maturation, capacity and sensitivity of Ca2+ signaling machinery increases dramatically, preparing the metaphase II (MII)-arrested egg for fertilization. Upon sperm-egg fusion, Ca2+ release from IP3-sensitive endoplasmic reticulum stores results in cytoplasmic Ca2+ oscillations that drive egg activation and initiate early embryo development. Premature Ca2+ release can cause parthenogenetic activation prior to fertilization; thus, preventing inappropriate Ca2+ signaling is crucial for ensuring robust MII arrest. Here, we show that regulator of G-protein signaling 2 (RGS2) suppresses Ca2+ release in MII eggs. Rgs2 mRNA was recruited for translation during oocyte maturation, resulting in ∼20-fold more RGS2 protein in MII eggs than in fully grown immature oocytes. Rgs2-siRNA-injected oocytes matured to MII; however, they had increased sensitivity to low pH and acetylcholine (ACh), which caused inappropriate Ca2+ release and premature egg activation. When matured in vitro, RGS2-depleted eggs underwent spontaneous Ca2+ increases that were sufficient to cause premature zona pellucida conversion. Rgs2−/− females had reduced litter sizes, and their eggs had increased sensitivity to low pH and ACh. Rgs2−/− eggs also underwent premature zona pellucida conversion in vivo. These findings indicate that RGS2 functions as a brake to suppress premature Ca2+ release in eggs that are poised on the brink of development. PMID:26160904
Exposure to high ambient temperatures alters embryology in rabbits
NASA Astrophysics Data System (ADS)
García, M. L.; Argente, M. J.
2017-09-01
High ambient temperatures are a determining factor in the deterioration of embryo quality and survival in mammals. The aim of this study was to evaluate the effect of heat stress on embryo development, embryonic size and size of the embryonic coats in rabbits. A total of 310 embryos from 33 females in thermal comfort zone and 264 embryos of 28 females in heat stress conditions were used in the experiment. The traits studied were ovulation rate, percentage of total embryos, percentage of normal embryos, embryo area, zona pellucida thickness and mucin coat thickness. Traits were measured at 24 and 48 h post-coitum (hpc); mucin coat thickness was only measured at 48 hpc. The embryos were classified as zygotes or two-cell embryos at 24 hpc, and 16-cells or early morulae at 48 hpc. The ovulation rate was one oocyte lower in heat stress conditions than in thermal comfort. Percentage of normal embryos was lower in heat stress conditions at 24 hpc (17.2%) and 48 hpc (13.2%). No differences in percentage of zygotes or two-cell embryos were found at 24 hpc. The embryo development and area was affected by heat stress at 48 hpc (10% higher percentage of 16-cells and 883 μm2 smaller, respectively). Zona pellucida was thicker under thermal stress at 24 hpc (1.2 μm) and 48 hpc (1.5 μm). No differences in mucin coat thickness were found. In conclusion, heat stress appears to alter embryology in rabbits.
Demi-embryo production from hatching of zona-drilled bovine and rabbit blastocysts.
Skrzyszowska, M; Smorag, Z; Katska, L
1997-09-01
It is known that the pregnancy rate resulting after transfer of bisected embryos is lower than after transfer of whole embryos. The main reason is the reduced cell number in the demi-embryo which is less than 1 2 of that in the intact embryo, since a number of blastomeres is damaged as a result of the procedure used in conventional embryo splitting. The aim of our experiment was to develop a non-invasive procedure which would limit cell losses during microsurgery. The experiment was carried out on bovine IVM-IVF embryos at middle, late and expanded blastocyst stage and rabbit embryos at late blastocyst stage cultured in vitro from in vivo produced zygotes. The zona pellucida of these embryos was drilled on the line between the inner cell mass and the trophoblast using a glass microneedle (= 2 microm) or micropipette (= 30 microm). The procedure resulted in expulsion of the blastocyst through the perforation and formation of an incomplete demi-embryo configuration, connected by a very thin cell bridge (figure eight in shape). To separate the parts of the embryo, the cell bridge was cut using a glass microneedle. During the separation only a few cells were damaged. As a result of the procedure 4 20 (20.0%), 48 144 (33.3%) and 3 40 (7.5%) middle, late and expanded blastocysts hatched according to the pattern described. The developed procedure could be considered as a non-invasive alternative to conventional embryo splitting.
Development of frozen-thawed demi-embryos and production of identical twin calves of different ages.
Seike, N; Sakai, M; Kanagawa, H
1991-02-01
The percentages of morphologically transferable embryos obtained from frozen-thawed demi-embryos which were embedded with or without agar, and from those with or without zonae pellucidae were 26.3% (5/19), 36.4% (8/22), 39.5% (15/38) and 40.0% (22/55), respectively. No significant differences were observed between these groups. Development to calves of frozen-thawed demi-embryos with or without zonae pellucidae was 25.0% (3/12) and 26.7% (4/15), respectively. There was also no significant difference between them. On the trial for production of identical twin calves of different ages, the pregnancy rates of fresh and frozen demi-embryos after transfer were 69.2% (9/13) and 11.1% (1/9), respectively. Out of 13 fresh demi-embryos and 9 frozen demi-embryos transferred, only one pair of identical twin male calves of different ages were produced. This frozen-thawed demi-embryo was stored for 43 days in liquid nitrogen before thawing and transfer. These twin calves were confirmed to be identical by blood typing. Although these calves had different birth dates, their growth rates indicated similar developmental patterns. We suggest that it is possible to produce identical twin calves of different ages. This possibility would be useful for predicting the sex, milk producing ability and progeny test of a pair of demi-embryos before a decision to transfer the other half of a pair is made.
Comparative Sperm Proteomics in Mouse Species with Divergent Mating Systems
Vicens, Alberto; Borziak, Kirill; Karr, Timothy L.; Roldan, Eduardo R.S.
2017-01-01
Abstract Sexual selection is the pervasive force underlying the dramatic divergence of sperm form and function. Although it has been demonstrated that testis gene expression evolves rapidly, exploration of the proteomic basis of sperm diversity is in its infancy. We have employed a whole-cell proteomics approach to characterize sperm divergence among closely related Mus species that experience different sperm competition regimes and exhibit pronounced variation in sperm energetics, motility and fertilization capacity. Interspecific comparisons revealed significant abundance differences amongst proteins involved in fertilization capacity, including those that govern sperm-zona pellucida interactions, axoneme components and metabolic proteins. Ancestral reconstruction of relative testis size suggests that the reduction of zona pellucida binding proteins and heavy-chain dyneins was associated with a relaxation in sperm competition in the M. musculus lineage. Additionally, the decreased reliance on ATP derived from glycolysis in high sperm competition species was reflected in abundance decreases in glycolytic proteins of the principle piece in M. spretus and M. spicilegus. Comparison of protein abundance and stage-specific testis expression revealed a significant correlation during spermatid development when dynamic morphological changes occur. Proteins underlying sperm diversification were also more likely to be subject to translational repression, suggesting that sperm composition is influenced by the evolution of translation control mechanisms. The identification of functionally coherent classes of proteins relating to sperm competition highlights the utility of evolutionary proteomic analyses and reveals that both intensified and relaxed sperm competition can have a pronounced impact on the molecular composition of the male gamete. PMID:28333336
Bromfield, Elizabeth G; Aitken, R John; Gibb, Zamira; Lambourne, Sarah R; Nixon, Brett
2014-02-01
While IVF has been widely successful in many domesticated species, the development of a robust IVF system for the horse remains an elusive and highly valued goal. A major impediment to the development of equine IVF is the fact that optimised conditions for the capacitation of equine spermatozoa are yet to be developed. Conversely, it is known that stallion spermatozoa are particularly susceptible to damage arising as a consequence of capacitation-like changes induced prematurely in response to semen handling and transport conditions. To address these limitations, this study sought to develop an effective system to both suppress and promote the in vitro capacitation of stallion spermatozoa. Our data indicated that the latter could be achieved in a bicarbonate-rich medium supplemented with a phosphodiesterase inhibitor, a cyclic AMP analogue, and methyl-β-cyclodextrin, an efficient cholesterol-withdrawing agent. The populations of spermatozoa generated under these conditions displayed a number of hallmarks of capacitation, including elevated levels of tyrosine phosphorylation, a reorganisation of the plasma membrane leading to lipid raft coalescence in the peri-acrosomal region of the sperm head, and a dramatic increase in their ability to interact with heterologous bovine zona pellucida (ZP) and undergo agonist-induced acrosomal exocytosis. Furthermore, this functional transformation was effectively suppressed in media devoid of bicarbonate. Collectively, these results highlight the importance of efficient cholesterol removal in priming stallion spermatozoa for ZP binding in vitro.
Social accountability in medical education--an Australian rural and remote perspective.
Worley, Paul; Murray, Richard
2011-01-01
Australia's medical education system is undergoing a socially motivated transformation focused on improving access to medical care for rural and remote communities. A rural and remote backbone of Rural Clinical Schools (RCS), University Departments of Rural Health, regional medical schools, and the postgraduate college, ACRRM, have enabled community responsive innovation and partnerships with rural health services that once would have been difficult to imagine. This article argues that this transformation is succeeding because of the passionate leadership of rural medical and community leaders, government seed funding to encourage rural medicine as an academic discipline, rigorous research and consultation that underpinned each step of the innovation pathway, and a political campaign to invest in rural medical education as a form of rural social capital.
NASA Astrophysics Data System (ADS)
Plummer, Niel; Sprinkle, Craig
2001-03-01
Geochemical reaction models were evaluated to improve radiocarbon dating of dissolved inorganic carbon (DIC) in groundwater from confined parts of the Upper Floridan aquifer in central and northeastern Florida, USA. The predominant geochemical reactions affecting the 14C activity of DIC include (1) dissolution of dolomite and anhydrite with calcite precipitation (dedolomitization), (2) sulfate reduction accompanying microbial degradation of organic carbon, (3) recrystallization of calcite (isotopic exchange), and (4) mixing of fresh water with as much as 7% saline water in some coastal areas. The calculated cumulative net mineral transfers are negligibly small in upgradient parts of the aquifer and increase significantly in downgradient parts of the aquifer, reflecting, at least in part, upward leakage from the Lower Floridan aquifer and circulation that contacted middle confining units in the Floridan aquifer system. The adjusted radiocarbon ages are independent of flow path and represent travel times of water from the recharge area to the sample point in the aquifer. Downgradient from Polk City (adjusted age 1.7 ka) and Keystone Heights (adjusted age 0.4 ka), 14 of the 22 waters have adjusted 14C ages of 20-30 ka, indicating that most of the fresh-water resource in the Upper Floridan aquifer today was recharged during the last glacial period. All of the paleowaters are enriched in 18O and 2H relative to modern infiltration, with maximum enrichment in δ18O of approximately 2.0‰. Résumé. Les modèles de réactions géochimiques ont été évalués afin de tester la datation par le radiocarbone du carbone minéral dissous (CMD) des eaux souterraines dans les parties captives de la nappe supérieure de Floride, en Floride centrale et nord-orientale (États-Unis). Les réactions géochimiques prédominantes affectant l'activité en 14C du CMD comprennent (1) la dissolution de la dolomite et de l'anhydrite accompagnée de la précipitation de la calcite (dédolomitisation), (2) la réduction des sulfates accompagnant une dégradation microbienne du carbone organique, (3) la recristallisation de la calcite (échange isotopique), et (4) le mélange d'eau douce avec de l'eau salée, jusqu'à 7%, dans certaines zones côtières. Les transferts minéraux nets calculés sont extrêmement faibles dans les parties situées dans l'amont de l'aquifère ils augmentent significativement dans les zones de l'aval, montrant en partie au moins l'existence d'une drainance ascendante depuis l'aquifère inférieur de Floride et une circulation qui met en relation les unités captives du système aquifère de Floride. Les âges radiocarbone corrigés sont indépendants des trajets d'écoulement et représentent des temps de transit de l'eau depuis la zone de recharge vers le point de prélèvement dans l'aquifère. En aval de Polk City (âge corrigé 1,7 ka) et de Keystone Heighats (âge corrigé 0,4 ka), 14 des 22 échantillons d'eau présentent des âges corrigés compris entre 20 et 30 ka, ce qui montre que la plus grande partie des ressources actuelles en eau douce de la nappe supérieure de Floride provient d'une recharge effectuée au cours de la dernière période glaciaire. Toutes ces eaux anciennes sont enrichies en 18O et en 2H par rapport à l'infiltration actuelle, avec un enrichissement maximal de δ18O d'environ 2.0‰. Resumen. Se han evaluado varios modelos geoquímicos con el fin de mejorar la datación del carbono inorgánico disuelto (CID) en las aguas subterráneas de las zonas confinadas del acuífero Superior de Florida, que ocupa el centro y nordeste de Florida (Estados Unidos). Las reacciones geoquímicas dominantes en cuanto a la actividad del 14C del CID incluyen: (1) disolución de dolomita y anhidrita, con precipitación de calcita (o de-dolomitización), (2) reducción de sulfato, acompañada por degradación microbiana de carbón orgánico, (3) recristalización de calcita (intercambio isotópico), y (4) mezcla de agua dulce con hasta un 7% de agua salina en algunas áreas costeras. Se ha calculado que las transferencias netas acumuladas de mineral son despreciables en las zonas situadas aguas arriba, y aumentan significativamente aguas abajo. Esto refleja, al menos en parte, el goteo desde el acuífero Inferior de Florida y la interconexión de las unidades confinantes en el sistema acuífero de Florida. Las edades de radiocarbono estimadas son independientes de las líneas de flujo y representan tiempos de tránsito de aguas desde el área de recarga hasta el punto de muestreo en el acuífero. Aguas debajo de la ciudad de Polk (edad de 1.700 años) y Keystone Heighats (edad de 400 años), 14 de las 22 muestras tienen edades estimadas de entre 20.000 y 30.000 años, hecho que indica que la mayor parte de los recursos actuales de agua dulce en el acuífero Superior de Florida fue recargada durante el último período glacial. Todas las paleoaguas están enriquecidas en 18O y 2H con respecto al agua actual de recarga, con un factor máximo de enriquecimiento en 18O de, aproximadamente, 2,0.
Booza, Jason C; Bridge, Patrick D; Neale, Anne Victoria; Schenk, Maryjean
2010-01-01
To address the shortage of physicians practicing in rural areas of Michigan, the Wayne State University School of Medicine developed an integrated rural core curriculum to interest students in rural practice careers. Here we focus on the evaluation strategy used to determine the extent to which students in the new rural medicine interest group who self-identified as selecting a rural clerkship or externship did secure a clinical training experience in a rural setting. Three measures of rurality were compared to determine whether students were placed in rural training settings: (1) the percentage of the county living in rural areas; (2) a county-level dichotomous measure of rural/nonrural; and (3) a dichotomous measure based on urban area boundaries within the county. Practice address and geographic data were integrated into geographic information systems software, which we used to map out rural characteristics of Michigan counties through a process called thematic mapping; this shows characteristic variation by color-shading geographic features. In addition, reference maps were created showing the boundaries of urban areas and metropolitan/micropolitan areas. Once these processes were completed, we overlaid the practice location on the contextual-level geographic features to produce a visual representation of the relationship between student placement and rural areas throughout the state. The outcome of student placement in rural practices varied by the definition of rural. We concluded that, although students were not placed in the most rural areas of Michigan, they received clerkship or externship training near rural areas or in semirural areas. This process evaluation had a direct impact on program management by highlighting gaps in preceptor recruitment. A greater effort is being made to recruit physicians for more rural areas of the state rather than urban and semirural areas. Geographic information systems mapping also defined levels of ruralism for students to help them make informed selections of training sties. This is especially important for students who are not sure about a rural experience and might be discouraged by placement in a remote rural area.
Matsumoto, Masatoshi; Inoue, Kazuo; Kajii, Eiji
2010-01-01
To show the impact of changing the definition of what is "rural" on the outcomes of a rural medical education program. A cross-sectional sample of 643 graduates under obligatory rural service and 1,699 graduates after serving their obligation, all from Jichi Medical University (JMU), a binding rural education program in Japan, were used as the data source. Communities were divided into decile groups according to population density, and the cut-off for "rural/nonrural" was altered in order to study its impact on the data. The rural practice rate of obliged graduates had its peak in the decile groups with the lowest population densities, while the peak rates of postobligation graduates and non-JMU physicians were at the decile groups with the highest population densities. Rural practice rates of all of the 3 groups of physicians increased with the increase in inclusiveness of rural definition. The ratio of rural practice rate of obliged graduates to that of non-JMU physicians ("relative effectiveness") increased remarkably with the increase in exclusiveness of rural definition. The relative effectiveness of postobligation graduates did not substantially increase after the cut-off exceeded a certain point of exclusiveness. Definition of "rural" largely determined the rural practice rate and relative effectiveness of JMU graduates. The results suggest that results of past outcome studies of rural medical education programs are potentially biased depending on how rural is defined.
Wheeler, Denna L; Hackler, Jeffrey B
2017-05-01
The physician shortage in Oklahoma coupled with geographic maldistribution of primary care physicians limits access to care in rural and underserved areas. One of the most effective strategies to recruit and retain physicians in rural areas is to create undergraduate and graduate medical education training sites in these locations. Oklahoma State University Center for Health Sciences College of Osteopathic Medicine has implemented a rural training program that begins with early recruitment of rural high school students, introduces medical students to rural practice options through rural clinical training opportunities, and provides opportunities to remain in rural Oklahoma for residency training through ongoing graduate medical education development. The purpose of this article is to provide a case study of the development of the college's Rural Medical Track. Preliminary findings indicate that rural-based clinical training for third- and fourth-year students strengthens performance on standardized tests.
Rural and Urban Youth Programs.
ERIC Educational Resources Information Center
Backman, Kenneth; And Others
This publication provides a variety of information on prevention and intervention programs for rural and urban children and adolescents. Drawing from a rural sociological perspective, the introductory paper defines "rural," discusses rural-urban economic and social differences, and lists indicators of risk for rural youth. It discusses the extent…
Kensington, Mary; Rankin, Jean; Gilkison, Andrea; Daellenbach, Rea; Crowther, Susan; Deery, Ruth; Davies, Lorna
2018-06-05
Rural practice presents unique challenges and skill requirements for midwives. New Zealand and Scotland face similar challenges in sustaining a rural midwifery workforce. This paper draws from an international multi-centre study exploring rural midwifery to focus on the education needs of student midwives within pre-registration midwifery programmes in order to determine appropriate preparation for rural practice. The mixed-methods study was conducted with 222 midwives working in rural areas in New Zealand (n = 145) and Scotland (n = 77). Midwives' views were gathered through an anonymous online survey and online discussion forums. Descriptive analysis was used for quantitative data and thematic analysis was conducted with qualitative data. 'Future proofing rural midwifery practice' using education was identified as the overarching central theme in ensuring the sustainability of rural midwives, with two associated principle themes emerging (i) 'preparation for rural practice' and (ii) 'living the experience and seeing the reality'. The majority of participants agreed that pre-registration midwifery programmes should include a rural placement for students and rural-specific education with educational input from rural midwives. This study provides insight into how best to prepare midwives for rural practice within pre-registration midwifery education, in order to meet the needs of midwives and families in the rural context. Copyright © 2018 Elsevier Ltd. All rights reserved.
Kwon, Dong H; Sandler, S G; Flegel, Willy A
2017-09-01
DEL red blood cells (RBCs) type as D- by routine serologic methods and are transfused routinely, without being identified as expressing a very weak D antigen, to D- recipients. DEL RBCs are detected only by adsorption and elution of anti-D or by molecular methods. Most DEL phenotypes have been reported in population studies conducted in East Asia, although DEL phenotypes have been detected also among Caucasian individuals. Approximately 98 percent of DEL phenotypes in East Asians are associated with the RHD*DEL1 or RHD*01EL.01 allele. The prevalence of DEL phenotypes has been reported among D- Han Chinese (30%), Japanese (28%), and Korean (17%) populations. The prevalence of DEL phenotypes is significantly lower among D- Caucasian populations (0.1%). Among the 3-5 percent of African individuals who are D-, there are no reports of the DEL phenotype. Case reports from East Asia indicate that transfusion of DEL RBCs to D- recipients has been associated with D alloimmunization. East Asian immigrants constitute 2.1 percent of the 318.9 million persons residing in the United States, and an estimated 2.8 percent are blood donors. Using these statistics, we estimate that 68-683 units of DEL RBCs from donors of East Asian ancestry are transfused as D- annually in the United States. Given the reports from East Asia of D alloimmunization attributed to transfusion of DEL RBCs, one would expect an occasional report of D alloimmunization in the United States following transfusion of DEL RBCs to a D- recipient. If such cases do occur, the most likely reason that they are not detected is the absence of active post-transfusion monitoring for formation of anti-D.
Poverty in the Rural United States.
ERIC Educational Resources Information Center
Dudenhefer, Paul
1993-01-01
The 1990 Rural Sociological Society's Task Force on Persistent Rural Poverty describes rural poverty, comparing it to urban poverty; rejects human-capital, economic-organization, and culture-of-poverty theories of rural poverty and proposes research on 10 other theories; and discusses rural policy and its inequitable emphasis on farmers. (KS)
CHANGING SCHOOL NEEDS IN RURAL AREAS.
ERIC Educational Resources Information Center
RHODES, ALVIN E.
AS THE RURAL ECONOMY HAS BECOME MORE AFFECTED BY AUTOMATION, RURAL SOCIETY HAS BECOME MORE INDUSTRIAL. FARM POPULATION AND THE NUMBER OF FARMS HAVE DECREASED, WHILE NON-FARM RURAL POPULATION HAS INCREASED. THE CHANGING RURAL SCENE IS REFLECTED IN CHANGES IN RURAL EDUCATION. EDUCATIONAL OPPORTUNITIES HAVE GREATLY INCREASED DUE TO SCHOOL…
Delinquent Behavior of Dutch Rural Adolescents
ERIC Educational Resources Information Center
Weenink, Don
2011-01-01
This article compares Dutch rural and non-rural adolescents' delinquent behavior and examines two social correlates of rural delinquency: communal social control and traditional rural culture. The analyses are based on cross-sectional data, containing 3,797 participants aged 13-18 (48.7% females). The analyses show that rural adolescents are only…
Increasing Caring and Reducing Violence in Rural Schools.
ERIC Educational Resources Information Center
Schroth, Gwen; Fishbaugh, Mary Susan
This paper briefly reviews the literature on violence in rural schools and communities, as well as the causes of rural crime and violence. General demographic and economic characteristics of rural communities are listed, followed by facts on rural school enrollments, achievement, and funding. Recent changes in rural communities that might…
Training For Rural Practice: The Way Ahead.
ERIC Educational Resources Information Center
Doolan, Thomas; Nichols, Anna
This report describes a program initiated in 1992 to provide appropriate training for rural physicians and to address the shortage of physicians in rural Australia. Rural medical practice differs dramatically from urban practice in that there is limited access to specialist services in rural areas, thus requiring rural practitioners to be…
ERIC Educational Resources Information Center
Congress of the U.S., Washington, DC. House Committee on Agriculture.
Testimony of H.R. 1800, the Rural Area Revitalization Act, and H.R. 2026, the Rural Development Reorganization Act focuses on the need for federal attention to rural problems other than agriculture. The Rural Area Revitalization Act authorizes expansion of capital available for lending in rural areas, a grant program of $25 million per year for…
Holst, Jens; Normann, Oliver; Herrmann, Markus
2015-01-01
After decades of providing a dense network of quality medical care, Germany is facing an increasing shortage of medical doctors in rural areas. Current graduation rates of generalists do not counterbalance the loss due to retirement. Informed by international evidence, different strategies to ensure rural medical care are under debate, including innovative teaching approaches during undergraduate training. The University of Magdeburg in Saxony-Anhalt was the first medical school in Germany to offer a rural elective for graduate students. During the 2014 summer semester, 14 medical students attended a two-weekend program in a small village in Northern Saxony-Anhalt that allowed them to become more familiar with a rural community and rural health issues. The elective course raised a series of relevant topics for setting up rural practice and provided students with helpful insight into living and working conditions in rural practice. Preliminary evaluations indicate that the rural medicine course allowed medical students to reduce pre-existing concerns and had positive impact on their willingness to set up a rural medical office after graduation. Even short-term courses in rural practice can help reduce training-related barriers that prevent young physicians from working in rural areas. Undergraduate medical training is promising to attenuate the emerging undersupply in rural areas.
Pang, S; Levine, L S; Stoner, E; Opitz, J M; Pollack, M S; Dupont, B; New, M I
1983-04-01
In studies of a 6-yr-old boy and his non-HLA identical 8-yr-old sister, we demonstrated 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) deficiency in the biosynthetic pathways of glucocorticoids and androgens, but not mineralocorticoids. The sister did not manifest abnormal genital development at birth, but developed premature adrenarche at the age of 4 yr, with clitoromegaly and advanced bone age. The brother had perineal hypospadias at birth and developed premature adrenarche at the age of 6 yr. In both siblings, baseline and ACTH-stimulated delta 5 steroids were markedly elevated. The baseline and ACTH-stimulated ratios of delta 5 to delta 4 steroids remained extremely high, and all steroids promptly suppressed with dexamethasone (DEX). Normal baseline PRA and serum and urinary aldosterone (Aldo) levels increased after stimulation with a low Na+ diet. Renal Na+ conservation was normal after dietary Na+ deprivation with and without DEX administration. The PRA to pH 1 Aldo ratio remained normal with normal and low Na+ diets, regardless of DEX administration, indicating normal glomerulosa function with renin stimulation. In both siblings, ACTH increased PRA and Aldo levels, maintaining the PRA to pH 1 Aldo ratio unchanged from the baseline value. In contrast, in control children, PRA was suppressed, while Aldo increased, resulting in a fall of the PRA to pH 1 Aldo ratio. The increase in PRA with exogenous ACTH in these siblings suggests there may be an ACTH-stimulable mineralocorticoid antagonist. During prolonged DEX administration, hCG administration caused a slight increase in 17-hydroxypregnenolone and dehydroepiandrosterone in both the siblings, while testosterone (T) rose poorly in the brother, and estradiol did not rise at all in the sister. These results suggest the possibility of a deficiency of 3 beta-HSD in the gonads as well as the adrenals. After [3H]dehydroepiandrosterone iv infusion, there was normal conversion to [3H]-conjugated testosterone glucuronide, suggesting the presence of normal peripheral 3 beta-HSD activity. We propose that in these siblings, there is a deficiency of 3 beta-HSD in the adrenal zona fasciculata and zona reticularis, whereas 3 beta-HSD activity is intact in the zona glomerulosa. In addition, in these siblings, 3 beta-HSD deficiency was present in the gonads, while peripheral 3 beta-HSD activity appeared to be intact. These cases demonstrate further the heterogeneity of congenital adrenal hyperplasia due to 3 beta-HSD deficiency.
Characteristics of Queensland physicians and the influence of rural exposure on practice location.
Runge, C E; MacKenzie, A; Loos, C; Waller, M; Gabbett, M; Mills, R; Eley, D
2016-08-01
The Queensland branch of the Royal Australasian College of Physicians (RACP) commissioned this study to update their workforce profile and examine rural practice. The present investigation aimed to describe characteristics of Queensland physicians and determine the influence of childhood and training locations on current rural practice. A cross-sectional online survey, conducted 4 July-4 November 2013, was administered to Fellows of The RACP, Queensland. Descriptive statistics report characteristics and logistic regression analyses identify associations and interactions. The outcome measure was current practice location using the Australian Standard Geographic Classification - Remoteness Area. Data were obtained for 633 physicians. Their average age was 49.5 years, a third was female and a quarter was in rural practice. Rural practice was associated with a rural childhood (odds ratio (OR) (95% confidence interval, CI) 1.89 (1.10, 3.27) P = 0.02) and any time spent as an intern (OR 4.07 (2.12, 7.82) P < 0.001) or registrar (OR 4.00 (2.21, 7.26) P < 0.001) in a rural location. Physicians with a rural childhood and rural training were most likely to be in rural practice. However, those who had a metropolitan childhood and a rural internship were approximately five times more likely to be working in rural practice than physicians with no rural exposure (OR 5.33 (1.61, 17.60) P < 0.01). The findings demonstrate the positive effect of rural vocational training on rural practice. A prospective study would determine if recent changes to the Basic Physician Training Pathway and the Basic Paediatric Training Network (more rural training than previous pathways) increases the rate of rural practice. © 2016 Royal Australasian College of Physicians.
Yanovski, J.A.; Diament, A.L.; Sovik, K.N.; Nguyen, T.T.; Li, H.; Sebring, N.G.; Warden, C.H.
2015-01-01
Background Little is known about genes affecting childhood body weight. Objective To examine alleles of the mitochondrial uncoupling protein-2 (UCP2) gene for association with obesity, since UCP2 may influence energy expenditure. Design We related UCP2 genotype to body composition, and to resting energy expenditure, in 105 children aged 6–10y. Overweight children and non-overweight children of overweight parents were genotyped for a 45 bp deletion/insertion (del/ins) in 3’ UTR of exon 8 and for an exon 4 C to T transition. Results 89 children were genotyped for the exon 8 allele: 50 children had del/del, 33 del/ins, and 6 ins/ins. Body mass index (BMI) was greater for del/ins (24.1 ± 5.9 kg/m2) than for del/del (20.4 ± 4.8 kg/m2, p<0.001). BMI of ins/ins (23.7 ± 7.8 kg/m2) was not different from del/ins. This effect was independent of race and gender (ANOVAs, p< 0.05). Body composition was also different according to UCP2 genotype. All body circumferences and skin fold thicknesses examined were significantly greater in del/ins than in del/del. DXA body fat mass (p<0.005) was also greater in del/ins than del/del. For 104 children genotyped at exon 4, no significant differences in BMI or body composition were found among the three exon 4 genotypes. Neither resting energy expenditure nor respiratory quotient were different according to UCP2 exon 4 or exon 8 genotype. Conclusion The exon 8 ins/del polymorphism of UCP2 appears to be associated with childhood-onset obesity. The UCP2/UCP3 genetic locus may play a role in childhood body weight. PMID:10837279
Lurry, Dee L.; Reutter, David C.; Wells, Frank C.; Rivera, M.C.; Munoz, A.
1998-01-01
La Oficina del Estudio Geologico de los Estados Unidos (U.S. Geological Survey, 0 USGS) ha monitoreado la calidad del agua de la cuenca del Rio Grande (Rio Bravo del Norte) desde 1995 como parte de la rediseiiada Red Nacional para Contabilizar la Calidad del Agua de los Rios (National Stream Quality Accounting Network, o NASOAN) (Hooper and others, 1997). EI programa NASOAN fue diseiiado para caracterizar las concentraciones y el transporte de sedimento y constituyentes quimicos seleccionados, encontrados en los grandes rios de los Estados Unidos - incluyendo el Misisipi, el Colorado y el Columbia, ademas del Rio Grande. En estas cuatro cuencas, el USGS opera actualmente (1998) una red de 40 puntos de muestreo pertenecientes a NASOAN, con un enfasis en cuantificar el flujo en masa (la cantidad de material que pasa por la estacion, expresado en toneladas por dial para cada constituyente. Aplicacando un enfoque consistente, basado en la cuantificacion de flujos en la cuenca del Rio Grande, el programa NASOAN esta generando la informacion necesaria para identificar fuentes regionales de diversos contaminantes, incluyendo sustancias qui micas agricolas y trazas elementos en la cuenca. EI efecto de las grandes reservas en el Rio Grande se puede observar segun los flujos de constituyentes discurren a 10 largo del rio. EI analisis de los flujos de constituyentes a escala de la cuenca proveera los medios para evaluar la influencia de la actividad humana sobre las condiciones de calidad del agua del Rio Grande.
HORVATH, KEITH J.; IANTAFFI, ALEX; SWINBURNE-ROMINE, REBECCA; BOCKTING, WALTER
2014-01-01
The aim of this study was to compare the mental health, substance use, and sexual risk behaviors of rural and non-rural transgender persons. Online banner advertisements were used to recruit 1,229 self-identified rural and non-rural transgender adults (18+ years) residing in the United States. Primary findings include significant differences in mental health between rural and non-rural transmen; relatively low levels of binge drinking across groups, although high levels of marijuana use; and high levels of unprotected sex among transwomen. The results confirm that mental and physical health services for transgender persons residing in rural areas are urgently needed. PMID:24380580
Horvath, Keith J; Iantaffi, Alex; Swinburne-Romine, Rebecca; Bockting, Walter
2014-01-01
The aim of this study was to compare the mental health, substance use, and sexual risk behaviors of rural and non-rural transgender persons. Online banner advertisements were used to recruit 1,229 self-identified rural and non-rural transgender adults (18+ years) residing in the United States. Primary findings include significant differences in mental health between rural and non-rural transmen; relatively low levels of binge drinking across groups, although high levels of marijuana use; and high levels of unprotected sex among transwomen. The results confirm that mental and physical health services for transgender persons residing in rural areas are urgently needed.
Arscott-Mills, Tonya; Kebaabetswe, Poloko; Tawana, Gothusang; Mbuka, Deogratias O; Makgabana-Dintwa, Orabile; Sebina, Kagiso; Kebaetse, Masego; Mokgatlhe, Lucky; Nkomazana, Oathokwa
2016-06-10
Botswana's medical school graduated its first class in 2014. Given the importance of attracting doctors to rural areas the school incorporated rural exposure throughout its curriculum. This study explored the impact of rural training on students' attitudes towards rural practice. The University of Botswana family medicine rural training sites, Maun and Mahalapye. The study used a mixed-methods design. After rural family medicine rotations, third- and fifth-year students were invited to complete a questionnaire and semi-structured interview. Data were analysed using descriptive statistics and thematic analysis. The thirty-six participants' age averaged 23 years and 48.6% were male. Thirtythree desired urban practice in a public institution or university. Rural training did not influence preferred future practice location. Most desired specialty training outside Botswana but planned to practice in Botswana. Professional stagnation, isolation, poorly functioning health facilities, dysfunctional referral systems, and perceived lack of learning opportunities were barriers to rural practice. Lack of recreation and poor infrastructure were personal barriers. Many appreciated the diversity of practice and supportive staff seen in rural practice. Several considered monetary compensation as an enticement for rural practice. Only those with a rural background perceived proximity to family as an incentive to rural practice. The majority of those interviewed plan to practice in urban Botswana, however, they did identify factors that, if addressed, may increase rural practice in the future. Establishing systems to facilitate professional development, strengthening specialists support, and deploying doctors near their home towns are strategies that may improve retention of doctors in rural areas.Keyords: rural health, student perceptions.
ERIC Educational Resources Information Center
Horn, Jerry, Ed.; Parmley, Fran, Ed.
This collection of 5 major papers and 32 abstracts covers a range of issues surrounding rural education. In the first paper, Glen Shaw, a rural Minnesota schools administrator, contends economic and technological changes have threatened rural jobs and the rural way of life. Anecdotes and statistics are employed to define rural problems and to urge…
Rural Stress: Myths and Realities.
ERIC Educational Resources Information Center
Hansen, Thomas D.; McIntire, Walter G.
A comparison between the common myths of "rural existence" and the documented realities of rural living explodes the myth that rural living is generally stress free, shows that life stress in rural settings can have deleterious effects on the function of individual and family, and provides a basis for exploring some implications of rural stress…
An Inquiry into Rural Dwellers' Opinions about Living Conditions in Urban and Rural Places.
ERIC Educational Resources Information Center
Azarkh, Emilia Davidovna; Korel, Liudmila Vasilyevna
Utilizing data derived from a questionnaire survey of the rural population of Novosibirsk province in the USSR, the following hypothesis was tested: the attitude of rural inhabitants toward urban and rural conditions is characterized by a considerable preponderance of positive evaluations of dominant rural conditions and transient urban conditions…
The New Vocationalism in Rural Locales.
ERIC Educational Resources Information Center
Theobald, Paul
This paper critiques current "school-to-work" practices in rural schools. A look at the rural context reveals that rural workers are more likely to be unemployed and are paid less than workers elsewhere, resulting in high rural poverty. In addition, many kinds of rural decline (in services, transportation, job availability) are tied to…
What is Happening in Rural Education Today: A Status Report.
ERIC Educational Resources Information Center
Tamblyn, Lewis R.
Arrayed by size of place, the U.S. rural population consitutes 31.4 percent of total U.S. population. Unfortunately, "rural" and "rural education" are often discussed as if they were separate entities. Actually they are inextricably interwoven, for those very factors which describe rurality very much determine rural education. Documenting the…
Profiles in Rural Economic Development: A Guidebook of Selected Successful Rural Area Initiatives.
ERIC Educational Resources Information Center
Thomas, Margaret G.
This guidebook presents 64 profiles of successful economic development initiatives in the small towns and rural areas of 37 states. Intended for use by rural and small town leaders and rural economic development specialists, the guide provides ideas, encouragement, and an "insider perspective" on alternative rural development strategies.…
THE EFFECT OF RURALITY ON THE EDUCATION OF RURAL YOUTH.
ERIC Educational Resources Information Center
CHARLES, EDGAR B.
THE PHENONMENON OF RURALITY OCCURS ALONG A RURAL-URBAN CONTINUUM, WITH THE DEGREE OF RURALITY DEPENDING UPON ENVIRONMENTAL, OCCUPATIONAL, AND SOCIO-CULTURAL CONSIDERATIONS. A HIGH DEGREE OF RURALITY IS LIKELY TO EXIST IN AREAS WHERE POPULATION CENTERS DO NOT EXCEED 2,500 PERSONS, OCCUPATIONS ARE PRIMARILY BASED ON NATURAL RESOURCE AND/OR LAND…
Rural America at a Glance. Rural Development Research Report.
ERIC Educational Resources Information Center
Economic Research Service (USDA), Washington, DC.
This report highlights the most recent indicators of social and economic conditions in rural areas for use in developing rural policies and programs. The economic expansion of the 1990s greatly benefited rural economies. Rural areas attracted both urban residents and immigrants. Hispanics accounted for over 25 percent of nonmetropolitan population…
Regenerating Rural Social Space? Teacher Education for Rural-Regional Sustainability
ERIC Educational Resources Information Center
Reid, Jo-Anne; Green, Bill; Cooper, Maxine; Hastings, Wendy; Lock, Graeme; White, Simone
2010-01-01
The complex interconnection among issues affecting rural-regional sustainability requires an equally complex program of research to ensure the attraction and retention of high-quality teachers for rural children. The educational effects of the construction of the rural within a deficit discourse are highlighted. A concept of rural social space is…
The Perceived Importance of University Presence in Rural Australia
ERIC Educational Resources Information Center
Drummond, Aaron; Halsey, R. John; van Breda, Marja
2011-01-01
The present study investigated rural residents' perceived importance of university presence in rural, regional and remote Australia. The present data indicate that the presence of university in rural areas is perceived as highly important by both rural and urban citizens. Results indicate that rural residents perceive that there is a need for…
Investing in People: The Human Capital Needs of Rural America. Rural Studies Series.
ERIC Educational Resources Information Center
Beaulieu, Lionel J., Ed.; Mulkey, David, Ed.
This book provides an overview of existing human resource conditions in rural America; examines key economic, social, and technological forces shaping the future viability of rural areas; describes human capital issues for rural women and minority groups; and outlines strategies to strengthen rural human capital resources. Chapters are: (1)…
Homeless Children: Addressing the Challenge in Rural Schools. ERIC Digest.
ERIC Educational Resources Information Center
Vissing, Yvonne M.
Despite stereotypes to the contrary, homelessness is as prevalent in rural as urban areas. This digest examines the implications of homelessness for rural children and youth and discusses possible actions by rural educators. An estimated half of the rural homeless are families with children. Compared to urban counterparts, rural homeless families…
Reconnecting Rural America. Report on Rural Intercity Passenger Transportation.
ERIC Educational Resources Information Center
Stommes, Eileen S.
This report summarizes the results of three regional symposia held during 1987-88 to gather grassroots information about rural passenger transportation needs across the country. The first section describes the structural transformation of rural America in the 1980s: (1) the rural economy; (2) rural population trends; (3) impact of information…
ERIC Educational Resources Information Center
Woofter, Thomas Jackson
Published in 1917, this book overviews rural schooling during the early 1900s and was written to address the problems of rural teaching and to serve as an introductory guide for rural teachers. Specifically, the book aimed to bring attention to the needs of rural life and the possible contributions of the rural school, to describe effective…
Education for Rural Development: Embedding Rural Dimensions in Initial Teacher Preparation
ERIC Educational Resources Information Center
Masinire, Alfred; Maringe, Felix; Nkambule, Thabisile
2014-01-01
In South Africa, rural education and development are issues of social justice, especially in places that were previously established as homelands. This article presents some of the tensions that are inherent in the conceptions of rurality, rural education and the possibility of sustainable rural education and development. We propose the notion of…
ERIC Educational Resources Information Center
Frazier, Barbara J.; Niehm, Linda S.; Stoel, Leslie
2012-01-01
The Rural Entrepreneurship Teaching Unit (RETU) is designed to acquaint university retailing and hospitality majors with rural entrepreneurship opportunities. The unit is an outcome of a federal grant focused on the contribution of the local retail sector to rural community resilience. The RETU integrates knowledge regarding rural development,…
NASA Astrophysics Data System (ADS)
Zhi, Wang; Kongan, Wu
2018-06-01
"Beautiful rural construction" is a systematic project, rural energy is one of the important contents of its construction. In accordance with the concept of eco-friendly construction, Beijing carried out a thorough "structural adjustment of rural energy optimization," "Earthquake energy-saving projects of rural housing" and other measures. By conventional heating technology research in Beijing 13 counties and 142 villages, we predict the future of rural energy will further the implementation of solar heating, electric heating and other new green energy technologies. It is suggested to establish the "Beijing Rural Information Service Platform" and "Beautiful Rural Information Resource Bank" through the means of informatization, which will greatly strengthen the regulation and control of rural people-land relationship and realize the systematic optimization, making the cities and villages have. Space for human survival and sustainable development.
Knight, Kaye; Kenny, Amanda; Endacott, Ruth
2016-06-01
To redefine the practice of rural nurses and describe a model that conceptualises the capabilities and characteristics required in the rural environment. The way in which the practice of rural nurses has been conceptualised is problematic. Definitions of rural nursing have been identified primarily through the functional context of rural health service delivery. The expert generalist term has provided a foundation theory for rural nurses with understandings informed by the scope of practice needed to meet service delivery requirements. However, authors exploring intrinsic characteristics of rural nurses have challenged this definition, as it does not adequately address the deeper, intangible complexities of practice required in the rural context. Despite this discourse, an alternative way to articulate the distinctive nature of rural nursing practice has eluded authors in Australia and internationally. A theoretical paper based on primary research. The development of the model was informed by the findings of a study that explored the nursing practice of managing telephone presentations in rural health services in Victoria, Australia. The study involved policy review from State and Federal governments, nursing and medical professional bodies, and five rural health services; semi-structured interviews with eight Directors of Nursing, seven registered nurses and focus group interviews with eight registered nurses. An ambiguity tolerance model drawn from corporate global entrepreneurship theory was adapted to explain the findings of the study. The adapted model presents capabilities and characteristics used by nurses to successfully manage the ambiguity of providing care in the rural context. Redefining the practice of rural nurses, through an adapted theory of ambiguity tolerance, highlights nursing characteristics and capabilities required in the rural context. This perspective offers new ways of thinking about the work of rural nurses, rural nurse policy, education, recruitment, retention and clinical governance. A greater understanding of rural nurse practice will assist in achieving positive care outcomes in an environment with competing stakeholder needs, and limited resources and options for care. © 2016 John Wiley & Sons Ltd.
Why doctors choose small towns: a developmental model of rural physician recruitment and retention.
Hancock, Christine; Steinbach, Alan; Nesbitt, Thomas S; Adler, Shelley R; Auerswald, Colette L
2009-11-01
Shortages of health care professionals have plagued rural areas of the USA for more than a century. Programs to alleviate them have met with limited success. These programs generally focus on factors that affect recruitment and retention, with the supposition that poor recruitment drives most shortages. The strongest known influence on rural physician recruitment is a "rural upbringing," but little is known about how this childhood experience promotes a return to rural areas, or how non-rural physicians choose rural practice without such an upbringing. Less is known about how rural upbringing affects retention. Through twenty-two in-depth, semi-structured interviews with both rural- and urban-raised physicians in northeastern California and northwestern Nevada, this study investigates practice location choice over the life course, describing a progression of events and experiences important to rural practice choice and retention in both groups. Study results suggest that rural exposure via education, recreation, or upbringing facilitates future rural practice through four major pathways. Desires for familiarity, sense of place, community involvement, and self-actualization were the major motivations for initial and continuing small-town residence choice. A history of strong community or geographic ties, either urban or rural, also encouraged initial rural practice. Finally, prior resilience under adverse circumstances was predictive of continued retention in the face of adversity. Physicians' decisions to stay or leave exhibited a cost-benefit pattern once their basic needs were met. These results support a focus on recruitment of both rural-raised and community-oriented applicants to medical school, residency, and rural practice. Local mentorship and "place-specific education" can support the integration of new rural physicians by promoting self-actualization, community integration, sense of place, and resilience. Health policy efforts to improve the physician workforce must address these complexities in order to support the variety of physicians who choose and remain in rural practice.
A qualitative study of medical students in a rural track: views on eventual rural practice.
Roseamelia, Carrie; Greenwald, James L; Bush, Tiffany; Pratte, Morgan; Wilcox, Jessica; Morley, Christopher P
2014-04-01
Rural tracks (RTs) exist within medical schools across the United States. These programs often target those students from rural areas and those with primary care career interests, given that these factors are robust predictors of eventual rural practice. However, only 26% to 64% of graduates from RTs enter eventual rural practice. We conducted a qualitative, exploratory study of medical students enrolled in one school's RT, examining their interests in rural training, specialization, and eventual rural practice, via open coding of transcripts from focus groups and in-depth individual interviews, leading to identification of emerging themes. A total of 16 out of 54 eligible first- and second-year preclinical medical students participated in focus group sessions, and a total of seven out of 17 eligible third- and fourth-year medical students participated in individual interviews. Analyses revealed the recognition of a "Rural Identity," typical characteristics, and the importance of "Program Fit" and "Intentions for Practice" that trended toward family medicine specialization and rural practice. However, nuances within the comments reveal incomplete commitment to rural practice. In many cases, student preference for rural practice was driven largely by a disinterest in urban practice. Students with rural and primary care practice interests are often not perfectly committed to rural practice. However, RTs may provide a haven for such students within medical school.
Petersen, Michael B; Grigoriadou, Maria; Koutroumpe, Maria; Kokotas, Haris
2012-07-01
Non-syndromic hearing loss is one of the most common hereditary determined diseases in human, and the disease is a genetically heterogeneous disorder. Mutations in the GJB2 gene, encoding connexin 26 (Cx26), are a major cause of non-syndromic recessive hearing impairment in many countries and are largely dependent on ethnic groups. Due to the high frequency of the c.35delG GJB2 mutation in the Greek population, we have previously suggested that Greek patients with sensorineural, non-syndromic deafness should be tested for the c.35delG mutation and the coding region of the GJB2 gene should be sequenced in c.35delG heterozygotes. Here we present on the clinical and molecular genetic evaluation of a family suffering from prelingual, sensorineural, non-syndromic deafness. A novel c.247_249delTTC (p.F83del) GJB2 mutation was detected in compound heterozygosity with the c.35delG GJB2 mutation in the proband and was later confirmed in the father, while the mother was homozygous for the c.35delG GJB2 mutation. We conclude that compound heterozygosity of the novel c.247_249delTTC (p.F83del) and the c.35delG mutations in the GJB2 gene was the cause of deafness in the proband and his father. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Rural Young People and Society: A Crisis of Attitudes
ERIC Educational Resources Information Center
Gur'ianova, M. P.
2013-01-01
Research on rural youth in Russia shows that keeping qualified and ambitious young people in the rural economy will require creating conditions for young people to exercise initiative in the rural economy and diminishing the gap in quality of life between rural and urban environments. Only in this way can the pessimism of rural youth be overcome.
ERIC Educational Resources Information Center
Lee, Mun Ho, Ed.
This proceedings contains approximately 92 presentations focusing on rural education and rural special education. Topics include: meeting the needs of handicapped and disabled students in rural areas; education and inservice training of special education teachers; teacher cooperation models; higher education of at-risk students; rural teacher…
ERIC Educational Resources Information Center
Tucker, Jamie; And Others
Almost everyone who responded to three transportation surveys of rural Handicapped Children's Early Education Program (HCEEP) projects identified transportation as a critical problem in the delivery of services to handicapped children in rural areas. Transportation problems encountered were attributed to environmental/geographic factors,…
Rural Roots: News, Information, and Commentary from the Rural School and Community Trust, 2000-2001.
ERIC Educational Resources Information Center
Westra, Kathryn E., Ed.; Yaunches, H. Alison, Ed.
2001-01-01
This document contains the first eight issues of "Rural Roots"--two published in 2000 and six published bimonthly in 2001. A newsletter of the Rural School and Community Trust, "Rural Roots" provides news, information, and commentary from the Rural Trust and highlights the wide variety of place-based education work happening in…
Education in Rural America: Object or Instrumentality of Rural Development.
ERIC Educational Resources Information Center
Hobbs, Daryl
Rural schools have had a traditional role as major vehicles of rural economic development. During the rapid economic changes of the 20th century rural schools supplied the literate migrants who flocked to the cities to become the human capital for urban based expansion. Rural schools also provided the literate farmers who stayed at home and…
Arguing for Rural Health in Medicare: A Progressive Rhetoric for Rural America
ERIC Educational Resources Information Center
Ricketts, Thomas C.
2004-01-01
Rural health policy is the laws, regulations, rules, and interpretations that benefit or affect health and health care for rural populations. This paper examines how rural health policy is viewed in the broader field of public policy, discusses the role of advocacy in developing rural health policy, and suggests ways to make that advocacy more…
A Brighter Future for Rural America? Strategies for Communities and States.
ERIC Educational Resources Information Center
John, DeWitt; And Others
This book outlines the competitive challenge facing rural America and discusses signs of hope for the rural economy. It reports some "secrets of success" in 16 rural farm belt counties that have gained employment while most rural areas are losing jobs. It also describes new state initiatives to help rural communities and lists operating…
ERIC Educational Resources Information Center
Sher, Jonathan; Sher, Katrina Rowe
This paper proposes a framework for developing a national rural development policy in Australia. Some common relevant misconceptions are that rural Australia and rural Australians are peripheral to the national economy and the nation's future, that farmers and farming communities are the alpha and omega of rural Australia, and that whatever is…
How Rural America Sees Its Future. The Main Street Economist: Commentary on the Rural Economy.
ERIC Educational Resources Information Center
Barkema, Alan D.; Drabenstott, Mark
To gain a perspective on rural America's future, seven roundtables consisting of seven rural stakeholder groups were convened. Four groups of challenges facing rural areas emerged. The rural business environment was considered the source of greatest challenge. Agriculture concerns included low profits and access to world markets. The effects of…
Rural Teacher Identity and Influencing Factors in Western China
ERIC Educational Resources Information Center
Mingren, Zhao; Shiquan, Fu
2018-01-01
The quality of rural teachers is a key factor affecting the quality of rural education. A better understanding of rural teachers is the basis for strengthening their development. It is possible to obtain a more holistic understanding of rural teachers' work and life through their identity. Based on a wealth of case-based information, rural teacher…
Plunkett, Robyn; Leipert, Beverly; Olson, Joanne
2016-09-01
In rural communities, religious places can significantly shape health for individuals, families, and communities. Rural churches are prominent community centers in rural communities and are deeply woven into rural culture. Thus, health influences arising from the rural church likely have health implications for the greater community. This article explores health influences emerging from rural churches using social determinants of health, social capital, and health expertise. Although nurses are important health resources for all populations, their value in rural areas may be exceedingly significant. The contribution of nurses to church-based health capital in rural communities may be quite significant and underestimated, although it remains poorly understood. © The Author(s) 2015.
An Interprofessional Rural Health Education Program
MacDowell, Martin; Schriever, Allison E.; Glasser, Michael; Schoen, Marieke D.
2012-01-01
Objectives. To develop, implement, and assess an interprofessional rural health professions program for pharmacy and medical students. Design. A recruitment and admissions process was developed that targeted students likely to practice in rural areas. Pharmacy students participated alongside medical students in completing the Rural Health Professions program curriculum, which included monthly lecture sessions and assignments, and a capstone clinical requirement in the final year. Assessment. Fourteen pharmacy students and 33 medical students were accepted into the program during the first 2 years of the Rural Health Professions program. Approximately 90% of the rural health professions students were originally from rural areas. Conclusions. The rural health professions program is an interprofessional approach to preparing healthcare providers to practice in rural communities. PMID:23275664
Lea, Jackie; Cruickshank, Mary
2015-10-01
To present the findings from the experienced rural nurse participants of a larger study that explored the transitional experiences of newly graduated nurses making the role transition in rural health care facilities in Australia. There are specific and unique aspects of rural nursing practice that influence the nature and timing of support for new graduate nurses that have not been explored or acknowledged as influencing the new graduate nurses' experience of transition. Specifically, the difficulties and challenges that experienced rural nurses face in providing effective and timely support for new graduate nurses who are making the transition to rural nursing practice is yet to be explored. Using a qualitative case study framework, this study specifically aimed to investigate and describe the nature and timing of support required during the transition to nursing practice that is specific for the rural context and capacity. Individual in-depth interviews were conducted with 16 experienced rural nurses who, at the time of the study, worked with new graduate nurses in the rural practice environment. The findings from this study showed that the provision of timely on-ward support for new graduates making the transition to rural nursing practice is affected and influenced by the skill mix and staffing allocation within the rural environment. As well, there is a lack of awareness by rural nurses of how to meet the on-ward support needs of new graduate nurses. This study has identified the specific and unique aspects of the rural nurse's role and responsibilities for which the new graduate nurse requires incremental learning and intensive clinical support. The findings can be used by rural health services and experienced rural registered nurses to assist in implementing adequate and timely support for new graduate nurses. © 2015 John Wiley & Sons Ltd.
Exposing some important barriers to health care access in the rural USA.
Douthit, N; Kiv, S; Dwolatzky, T; Biswas, S
2015-06-01
To review research published before and after the passage of the Patient Protection and Affordable Care Act (2010) examining barriers in seeking or accessing health care in rural populations in the USA. This literature review was based on a comprehensive search for all literature researching rural health care provision and access in the USA. Pubmed, Proquest Allied Nursing and Health Literature, National Rural Health Association (NRHA) Resource Center and Google Scholar databases were searched using the Medical Subject Headings (MeSH) 'Rural Health Services' and 'Rural Health.' MeSH subtitle headings used were 'USA,' 'utilization,' 'trends' and 'supply and distribution.' Keywords added to the search parameters were 'access,' 'rural' and 'health care.' Searches in Google Scholar employed the phrases 'health care disparities in the USA,' inequalities in 'health care in the USA,' 'health care in rural USA' and 'access to health care in rural USA.' After eliminating non-relevant articles, 34 articles were included. Significant differences in health care access between rural and urban areas exist. Reluctance to seek health care in rural areas was based on cultural and financial constraints, often compounded by a scarcity of services, a lack of trained physicians, insufficient public transport, and poor availability of broadband internet services. Rural residents were found to have poorer health, with rural areas having difficulty in attracting and retaining physicians, and maintaining health services on a par with their urban counterparts. Rural and urban health care disparities require an ongoing program of reform with the aim to improve the provision of services, promote recruitment, training and career development of rural health care professionals, increase comprehensive health insurance coverage and engage rural residents and healthcare providers in health promotion. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Kingston, Gail A; Williams, Gary; Judd, Jenni; Gray, Marion A
2015-04-01
The aim of this study was to explore how interventions were provided to meet the needs of rural/remote residents who have had a traumatic hand injury, including the coordination of services between rural/remote and metro/regional therapists. Barriers to providing services, use of technology and professional support provided to therapists in rural/remote areas were also explored. Cross-sectional survey. Metropolitan/regional and rural/remote public health facilities in Australia. Occupational therapists and physiotherapists who provide hand therapy to rural/remote patients. Quantitative and qualitative questionnaire responses analysed with descriptive statistics and inductive analysis. There were 64 respondents out of a possible 185. Over half of rural/remote respondents provided initial splinting and exercise prescriptions, and over 85% reported that they continued with exercise protocols. Videoconferencing technology for patient intervention and clinical review was used by 39.1% respondents. Barriers to providing services in rural/remote locations included transport, travelling time, limited staff, and lack of expert knowledge in hand injuries or rural/remote health care. Four major themes emerged from the open-ended questions: working relationships, patient-centred care, staff development and education, and rural and remote practice. The use of technology across Australia to support rural/remote patient intervention requires attention to achieve equity and ease of use. Flexible and realistic goals and interventions should be considered when working with rural/remote patients. A shared care approach between metropolitan/regional and rural/remote therapists can improve understanding of rural/remote issues and provide support to therapists. Further research is recommended to determine the suitability of this approach when providing hand therapy to rural/remote residents. © 2015 National Rural Health Alliance Inc.
Bowblis, John R; Meng, Hongdao; Hyer, Kathryn
2013-01-01
Objective To identify and quantify the sources of the urban-rural disparity in facility-acquired contracture rates in nursing homes. Data Sources Survey inspection data of U.S. nursing homes from 1999 to 2008 and standardized national rural definition file from the Rural-Urban Commuting Area Codes. Study Design We estimated regressions of facility-level contracture rate as a function of urban-rural categories (urban, micropolitan, small rural town, and isolated small rural town) and other related facility characteristics to identify size of the urban-rural disparity. We used Blinder–Oaxaca decomposition techniques to determine the extent to which the disparity is attributable to the differences in facility and aggregate resident characteristics. Principal Findings Rural nursing homes have higher contracture rates than urban nursing homes. About half of the urban-rural disparity is explained by differences in observable characteristics among urban and rural nursing homes. Differences in staffing levels explain less than 5 percent of the disparity, case-mix explains 6–8 percent, and structure and operational characteristics account for 10–22 percent of the disparity. Conclusion While a lower level and quality of staffing are a concern for rural nursing homes, facility structure and funding sources explain a larger proportion of the urban-rural disparity in the quality of care. PMID:22670847
Bowblis, John R; Meng, Hongdao; Hyer, Kathryn
2013-02-01
To identify and quantify the sources of the urban-rural disparity in facility-acquired contracture rates in nursing homes. Survey inspection data of U.S. nursing homes from 1999 to 2008 and standardized national rural definition file from the Rural-Urban Commuting Area Codes. We estimated regressions of facility-level contracture rate as a function of urban-rural categories (urban, micropolitan, small rural town, and isolated small rural town) and other related facility characteristics to identify size of the urban-rural disparity. We used Blinder-Oaxaca decomposition techniques to determine the extent to which the disparity is attributable to the differences in facility and aggregate resident characteristics. Rural nursing homes have higher contracture rates than urban nursing homes. About half of the urban-rural disparity is explained by differences in observable characteristics among urban and rural nursing homes. Differences in staffing levels explain less than 5 percent of the disparity, case-mix explains 6-8 percent, and structure and operational characteristics account for 10-22 percent of the disparity. While a lower level and quality of staffing are a concern for rural nursing homes, facility structure and funding sources explain a larger proportion of the urban-rural disparity in the quality of care. © Health Research and Educational Trust.
Modelo semi-empírico de protuberancia solar a partir del diagnóstico de densidades
NASA Astrophysics Data System (ADS)
Cirigliano, D.; Vial, J. C.; Rovira, M.
A partir de la observación del espectro del quintuplete de C III alrededor de 1175 Å, se ha realizado el diagnóstico de la densidad y presión electrónica, basado en el cálculo del cociente de las intensidades observadas. Una vez establecida la densidad electrónica, y con el cálculo de las velocidades Doppler, hemos investigado el flujo de masa en la protuberancia en función de la temperatura. Estableciendo como hipótesis la conservación del número de partículas que ingresan y salen del cuerpo de la protuberancia, se investiga la variación del área de un tubo de flujo semi-empírico en función de la temperatura. A partir de dicho diagnóstico, se examina el comportamiento del radio del tubo magnético en función de la temperatura, los que dan cuenta de la abertura de las líneas de campo magnético que confinan el plasma y de la divergencia del campo magnético en diferentes alturas de la atmósfera solar.
Smith, Tina Anderson; Adimu, Tanisa Foxworth; Martinez, Amanda Phillips; Minyard, Karen
2016-01-01
This paper explores how communities translate evidence-based and promising health practices to rural contexts. A descriptive, qualitative analysis was conducted using data from 70 grantees funded by the Federal Office of Rural Health Policy to implement evidence-based health practices in rural settings. Findings were organized using The Interactive Systems Framework for Dissemination and Implementation. Grantees broadly interpreted evidence-based and promising practices, resulting in the implementation of a patchwork of health-related interventions that fell along a spectrum of evidentiary rigor. The cohort faced common challenges translating recognized practices into rural community settings and reported making deliberate modifications to original models as a result. Opportunities for building a more robust rural health evidence base include investments to incentivize evidence-based programming in rural settings; rural-specific research and theory-building; translation of existing evidence using a rural lens; technical assistance to support rural innovation; and prioritization of evaluation locally.
Health and sustainability of rural communities.
Ryan-Nicholls, K D
2004-01-01
The challenges associated with rural and remote health have been widely acknowledged by rural communities and the health care community for some time now. However, it is only recently that any concerted effort has begun to address these difficulties. The aim of this paper was to examine the issue of rural health and sustainability internationally with a particular emphasis on the Canadian context. This paper used a framework to: articulate the nature of rural health and sustainability; examine the historical, socio-cultural, ethical, legal, economic and political aspects of rural health and sustainability; delineate the importance and significance of rural health and sustainability to Canadian citizens, and analyze progress made in relation to rural health and sustainability. This paper concludes by cautioning that rural health and sustainability can only be enhanced by innovative strategies that employ both capacity building partnerships with rural people that are supported overall, by adequate funding allocation.
Rural/Nonrural Differences in College Attendance Patterns.
Byun, Soo-Yong; Irvin, Matthew J; Meece, Judith L
Using data from the National Education Longitudinal Study of 1988, this study documented college attendance patterns of rural youth in terms of the selectivity of first postsecondary institution of attendance, the timing of transition to postsecondary education, and the continuity of enrollment. The study also examined how these college attendance patterns among rural students differed from those among their non-rural counterparts and which factors explained these rural/nonrural differences. Results showed that rural youth were less likely than their nonrural counterparts to attend a selective institution. In addition, rural youth were more likely to delay entry to postsecondary education, compared to their urban counterparts. Finally, rural students were less likely than their urban counterparts to be continuously enrolled in college. Much of these rural/nonrural disparities in college attendance patterns were explained by rural/nonrural differences in socioeconomic status and high school preparation. Policy implications, limitations of the study, and future research directions are also discussed.
Does Missed Care in Isolated Rural Hospitals Matter?
Smith, Jessica G
2018-06-01
Missed care is associated with adverse outcomes such as patient falls and decreased nurse job satisfaction. Although studied in populations of interest such as neonates, children, and heart failure patients, there are no studies about missed care in rural hospitals. Reducing care omissions in rural hospitals might help improve rural patient outcomes and ensure that rural hospitals can remain open in an era of hospital reimbursement dependent on care outcomes, such as through value-based purchasing. Understanding the extent of missed nursing care and its implications for rural populations might provide crucial information to alert rural hospital administrators and nurses about the incidence and influence of missed care on health outcomes. Focusing on missed care within rural hospitals and other rural health care settings is important to address the specific health needs of aging rural U.S. residents who are isolated from high-volume, urban health care facilities.
Rural/Nonrural Differences in College Attendance Patterns
Byun, Soo-yong; Irvin, Matthew J.; Meece, Judith L.
2014-01-01
Using data from the National Education Longitudinal Study of 1988, this study documented college attendance patterns of rural youth in terms of the selectivity of first postsecondary institution of attendance, the timing of transition to postsecondary education, and the continuity of enrollment. The study also examined how these college attendance patterns among rural students differed from those among their non-rural counterparts and which factors explained these rural/nonrural differences. Results showed that rural youth were less likely than their nonrural counterparts to attend a selective institution. In addition, rural youth were more likely to delay entry to postsecondary education, compared to their urban counterparts. Finally, rural students were less likely than their urban counterparts to be continuously enrolled in college. Much of these rural/nonrural disparities in college attendance patterns were explained by rural/nonrural differences in socioeconomic status and high school preparation. Policy implications, limitations of the study, and future research directions are also discussed. PMID:25983357
Yin, C Cameron; Tang, Guilin; Lu, Gary; Feng, Xiaoli; Keating, Michael J; Medeiros, L Jeffrey; Abruzzo, Lynne V
2015-08-01
Deletion 20q (Del(20q)), a common cytogenetic abnormality in myeloid neoplasms, is rare in chronic lymphocytic leukemia. We report 64 patients with chronic lymphocytic leukemia and del(20q), as the sole abnormality in 40, a stemline abnormality in 21, and a secondary abnormality in 3 cases. Fluorescence in situ hybridization (FISH) analysis revealed an additional high-risk abnormality, del(11q) or del(17p), in 25/64 (39%) cases. In most cases, the leukemic cells showed atypical cytologic features, unmutated IGHV (immunoglobulin heavy-chain variable region) genes, and ZAP70 positivity. The del(20q) was detected only after chemotherapy in all 27 cases with initial karyotypes available. With a median follow-up of 90 months, 30 patients (47%) died, most as a direct consequence of chronic lymphocytic leukemia. Eight patients developed a therapy-related myeloid neoplasm, seven with a complex karyotype. Combined morphologic and FISH analysis for del(20q) performed in 12 cases without morphologic evidence of a myeloid neoplasm localized the del(20q) to the chronic lymphocytic leukemia cells in 5 (42%) cases, and to myeloid/erythroid cells in 7 (58)% cases. The del(20q) was detected in myeloid cells in all 4 cases of myelodysplastic syndrome. In aggregate, these data indicate that chronic lymphocytic leukemia with del(20q) acquired after therapy is heterogeneous. In cases with morphologic evidence of dysplasia, the del(20q) likely resides in the myeloid lineage. However, in cases without morphologic evidence of dysplasia, the del(20q) may represent clonal evolution and disease progression. Combining morphologic analysis with FISH for del(20q) or performing FISH on immunomagnetically selected sub-populations to localize the cell population with this abnormality may help guide patient management.
Yin, C. Cameron; Tang, Guilin; Lu, Gary; Feng, Xiaoli; Keating, Michael J.; Medeiros, L. Jeffrey; Abruzzo, Lynne V.
2015-01-01
Del(20q), a common cytogenetic abnormality in myeloid neoplasms, is rare in chronic lymphocytic leukemia. We report 64 patients with chronic lymphocytic leukemia and del(20q), as the sole abnormality in 40, a stemline abnormality in 21, and a secondary abnormality in 3 cases. FISH analysis revealed an additional high-risk abnormality, del(11q) or del(17p), in 27/64 (42%) cases. In most cases, the leukemic cells showed atypical cytologic features, unmutated IGHV genes and ZAP70 positivity. The del(20q) was detected only after chemotherapy in all 27 cases with initial karyotypes available. With a median follow-up of 90 months, 30 patients (47%) died, most as a direct consequence of chronic lymphocytic leukemia. Eight patients developed a therapy-related myeloid neoplasm, seven with a complex karyotype. Combined morphologic and FISH analysis for del(20q) performed in 12 cases without morphologic evidence of a myeloid neoplasm localized the del(20q) to the chronic lymphocytic leukemia cells in 5 (42%) cases, and to myeloid/erythroid cells in 7 (58)% cases. The del(20q) was detected in myeloid cells in all 4 cases of myelodysplastic syndrome. In aggregate, these data indicate that chronic lymphocytic leukemia with del(20q) acquired after therapy is heterogeneous. In cases with morphologic evidence of dysplasia, the del(20q) likely resides in the myeloid lineage. However, in cases without morphologic evidence of dysplasia, the del(20q) may represent clonal evolution and disease progression. Combining morphologic analysis with FISH for del(20q) or performing FISH on immunomagnetically-selected subpopulations to localize the cell population with this abnormality may help guide patient management. PMID:25953391
Teledermatology in Tijuana, Mexico.
Brown, Megan
2016-12-01
The Health Frontiers in Tijuana (HFiT) clinic is a binational partnership between the University of California, San Diego School of Medicine (San Diego, California); the Universidad Autónoma de Baja California School of Medicine (Tijuana, Mexico); and Desayunador Salesiano Padre Chava, a community grassroots organization in Tijuana, Mexico. Health Frontiers in Tijuana provides accessible quality health care for the underserved in Tijuana's Zona Norte. This article is a narrative meant to share my clinical experience as a dermatology resident who worked with HFiT to establish teledermatology services at this clinic.
Studies on trypsin-like enzymes in sperm and early embryos
DOE Office of Scientific and Technical Information (OSTI.GOV)
Penn, A.
1975-12-09
Results are reported from a study of acrosomal proteinase, a trypsin-like enzyme (TLE), found in the acrosome of all eutherian mammals studied to date. It has been implicated in the dissolution of a passage for the sperm through the zona pellucida of the egg, a step necessary for in vivo fertilization. A cytochemical procedure employing autoradiographic film as a gelatin substrate is described for in situ detection and localization of acrosomal proteolytic activity. A role for TLE in the early development of embryos is suggested. (CH)
Increasing Naval Security Cooperation between the U.S., Chile and Peru
2009-03-01
del Mar: La Marina de Guerra en la historia del Perú (Lima: Marina de Guerra del Perú, 1994), 184. 108 Ibid., 188. 109 Ibid., 191-193. 42 “the...La Marina de Guerra en la historia del Perú, 205. 111 Ibid. 112 Ibid., 210. 113 Ibid., 229. 114 Ibid., 230. 115 Ibid., 246. 43 contributed to...la Puente Brunke, Los Hombres del Mar: La Marina de Guerra en la historia del Perú, 252. 117 Ibid., 264. 118 Ibid., 302. 119 Ibid., 342. 44
Rural-urban differences of neonatal mortality in a poorly developed province of China.
Yi, Bin; Wu, Li; Liu, Hong; Fang, Weimin; Hu, Yang; Wang, Youjie
2011-06-18
The influence of rural-urban disparities in children's health on neonatal death in disadvantaged areas of China is poorly understood. In this study of rural and urban populations in Gansu province, a disadvantaged province of China, we describe the characteristics and mortality of newborn infants and evaluated rural-urban differences of neonatal death. We analyzed all neonatal deaths in the data from the Surveillance System of Child Death in Gansu Province, China from 2004 to 2009. We calculated all-cause neonatal mortality rates (NMR) and cause-specific death rates for infants born to rural or urban mothers during 2004-09. Rural-urban classifications were determined based on the residence registry system of China. Chi-square tests were used to compare differences of infant characteristics and cause-specific deaths by rural-urban maternal residence. Overall, NMR fell in both rural and urban populations during 2004-09. Average NMR for rural and urban populations was 17.8 and 7.5 per 1000 live births, respectively. For both rural and urban newborn infants, the four leading causes of death were birth asphyxia, preterm or low birth weight, congenital malformation, and pneumonia. Each cause-specific death rate was higher in rural infants than in urban infants. More rural than urban neonates died out of hospital or did not receive medical care before death. Neonatal mortality declined dramatically both in urban and rural groups in Gansu province during 2004-09. However, profound disparities persisted between rural and urban populations. Strategies that address inequalities of accessibility and quality of health care are necessary to improve neonatal health in rural settings in China.
Schofield, D J; Page, S L; Lyle, D M; Walker, T J
2006-01-01
To compare the impact of ageing on the GP and nursing rural and city workforce. Cohort analysis of Australian Bureau of Statistics census data. The data was used to examine the age distribution of the city and rural GP and nursing workforce; patterns of attrition for those 50 years and over; and the impact of changes in working hours. The rural GP and nursing workforce is significantly older than their city counterparts (p<0.001) with the 'baby boomer' generation making up 52% of city GPs but 59% of rural GPs in 2001. While a large proportion of city and rural GPs continued to work past the age of 65 years, rural GPs left the workforce at a significantly younger age than city doctors (p<0.001). Rural nurses are older than their city peers (p<0.001) but retire at an older age than city nurses (p<0.001). In 1986, a significantly higher proportion of rural GPs in all age cohorts worked more than 41 hours per week compared with their city counterparts (p<0.001). By 2001, rural 'generation X' GPs were no more likely to work long hours than those in the city (p<0.001). However, significantly more rural than city 'baby boomers' continued to work long hours. Rural GPs are retiring faster than city GPs and strategies to attract rural GPs and nurses will be critical to ensure adequate rural health care and that current rural workforce shortage do not worsen.
Sociodemographic and environmental correlates of active commuting in rural America.
Fan, Jessie X; Wen, Ming; Kowaleski-Jones, Lori
2015-01-01
This research investigated participation rates in 3 modes of active commuting (AC) and their sociodemographic and physical environmental correlates in rural America. The 2000 Census supplemented with other data sets were used to analyze AC rates in percentage of workers walking, biking, and taking public transportation to work in 14,209 nonmetropolitan rural tracts identified by RUCA codes, including 4,067 small rural and 10,142 town-micropolitan rural tracts. Sociodemographic and physical environmental variables were correlated with 3 AC modes simultaneously using Seemingly Unrelated Regression for nonmetro rural, and for small rural and town-micropolitan rural separately. The average AC rates in rural tracts were 3.63%, 0.26%, and 0.56% for walking, biking, and public transportation to work, respectively, with small rural tracts having a higher rate of walking but lower rates of biking and public transportation to work than town-micropolitan tracts. In general, better economic well-being was negatively associated with AC but percentage of college-educated was a positive correlate. Population density was positively associated with AC but greenness and proximity to parks were negative correlates. However, significant differences existed for different AC modes, and between small rural and town-micropolitan rural tracts. Sociodemographic factors explained more variance in AC than physical environmental factors but the detailed relationships were complex, varying by AC mode and by degree of rurality. Any strategy to promote AC in rural America needs to be sensitive to the population size of the area and assessed in a comprehensive manner to avoid a "one size fits all" approach. © 2014 National Rural Health Association.
Rural Industry Clustering Towards Transitional Rural-Urban Interface
NASA Astrophysics Data System (ADS)
Nugroho, P.
2018-05-01
Rural industrialization seems to be attractive for policymakers looking for counter-urbanization efforts – and nowadays peri-urbanization forces – in line with growing decentralized autonomy of local Indonesian authorities. To promote better rural development, an extended growth pole strategy has been introduced as well as an agropolitan approach and its derivatives. In fact, there is little evidence for their success; rural autonomy remains elusive instead. However, institutional capacity of rural authorities and organizations still fails to deliver rural development initiatives properly. This research was aimed at examining this issue by looking at rural industry clustering in the Greater Solo Region, Indonesia as a response against extended urbanization in peripheral regions. The study focused on batik industry clustering in the rural periphery of Solo City, which provides a transitional rural-urban interface necessary to drive rural independence. Having inherited the batik tradition underpinned by an agriculture-led peasant society, the rural batik industrialization has reinforced the socio-economic transition from a purely agrarian society to a mixed rural-urban society. This study employed an explanatory sequential mixed-method approach, where a quantitative spatial analysis was used to identify the expansion of urbanized areas in villages, and a qualitative case study analysis to figure out the socio-economic shift in rural livelihoods. The results showed that physical spatial changes in these villages do not conform to the socio-economic change into an urban industrial society in a substantial way. Rather, the local villagers preserve an informal economy to support the existence of a mixed rural-urban livelihood.
Optimizing Telehealth Strategies for Subspecialty Care: Recommendations from Rural Pediatricians
Demirci, Jill R.; Bogen, Debra L.; Mehrotra, Ateev; Miller, Elizabeth
2015-01-01
Abstract Background: Telehealth offers strategies to improve access to subspecialty care for children in rural communities. Rural pediatrician experiences and preferences regarding the use of these telehealth strategies for children's subspecialty care needs are not known. We elicited rural pediatrician experiences and preferences regarding different pediatric subspecialty telehealth strategies. Materials and Methods: Seventeen semistructured telephone interviews were conducted with rural pediatricians from 17 states within the United States. Interviewees were recruited by e-mails to a pediatric rural health listserv and to rural pediatricians identified through snowball sampling. Themes were identified through thematic analysis of interview transcripts. Institutional Review Board approval was obtained. Results: Rural pediatricians identified several telehealth strategies to improve access to subspecialty care, including physician access hotlines, remote electronic medical record access, electronic messaging systems, live video telemedicine, and telehealth triage systems. Rural pediatricians provided recommendations for optimizing the utility of each of these strategies based on their experiences with different systems. Rural pediatricians preferred specific telehealth strategies for specific clinical contexts, resulting in a proposed framework describing the complementary role of different telehealth strategies for pediatric subspecialty care. Finally, rural pediatricians identified additional benefits associated with the use of telehealth strategies and described a desire for telehealth systems that enhanced (rather than replaced) personal relationships between rural pediatricians and subspecialists. Conclusions: Rural pediatricians described complementary roles for different subspecialty care telehealth strategies. Additionally, rural pediatricians provided recommendations for optimizing individual telehealth strategies. Input from rural pediatricians will be crucial for optimizing specific telehealth strategies and designing effective telehealth systems. PMID:25919585
James, Wesley; Cossman, Jeralynn S
2017-01-01
The rural mortality penalty-growing disparities in rural-urban macro-level mortality rates-has persisted in the United States since the mid 1980s. Substantial intrarural differences exist: rural places of modest population size, close to urban areas, experience a greater mortality burden than the most rural locales. This research builds on recent findings by examining whether a race-specific rural mortality penalty exists; that is, are some rural areas more detrimental to black and/or white mortality than others? Using data from the Compressed Mortality File from 1968 to 2012, we calculate annual age-adjusted, race-specific mortality rates for all rural-urban regions designated by the Rural-Urban Continuum Codes. Indicators for population, socioeconomic status, and health infrastructure, as a proxy for access to care, are used as predictors of race-specific mortality in multivariable regression models. Three important results emerge from this analysis: (1) there is a substantial mortality disadvantage for both black and white rural Americans, (2) the most advantageous regions of mortality for blacks exhibit higher mortality than the most disadvantageous regions for whites, and (3) access to health care is a much stronger predictor of white mortality than black mortality. The rural mortality penalty is evident in race-specific mortality trends over time, with an added disadvantage in black mortality. The rate of mortality improvement for rural blacks and whites lags behind their same-race, urban counterparts, creating a diverging gap in race-specific mortality trends in rural America. © 2016 National Rural Health Association.
What do beginning students, in a rurally focused medical course, think about rural practice?
Young, Louise; Lindsay, Daniel B; Ray, Robin A
2016-12-07
Medical schools may select students for their attitudes towards rural medical practice, yet the rural-urban disparity in availability of medical practitioners and services has not diminished in recent times despite government initiatives and increasing numbers being trained for a career in medicine. One medical school, with a focus on rural and remote medicine, aims to select students with positive perceptions for rural medical practice. A research project collected data on the perceptions of these medical students in the first week of their medical studies. Students completed a low stakes essay on the life and work of a rural doctor. Initially, this formed part of a literacy assessment to determine any students requiring remediation. All students were asked if they would consent to their essay being reviewed for a research project. Data was obtained from those students who consented and handed their essays in for review. The 103 student essays underwent thematic analysis and sentences were coded into three main themes of rural lifestyle, doctor role and rural practice. Second level themes were further elicited and results were quantified according to whether they were positive or negative. Positive themes included rural lifestyle, doctor role, views of doctor, impact on community, broader work and skills knowledge, and better relationships with community and patients. Negative themes included doctor's health, pressure on doctor, family problems, greater workload, privacy and confidentiality issues, cultural issues, isolation, limited resources and financial impacts. Quantitisation of this data was used to transform essay sentences into a numerical form which allowed statistical analysis and comparison of perceptions using Z tests. No significant differences on the number of positive and negative responses for rural lifestyle and rural practice were found. The rural doctor role had a significantly more positive than negative views. Significant differences were found for positive views of the rural doctor role and negative views of rural practice. Participants from a capital city background reported a significantly higher percentage of responses related to negative views of rural practice than their regional and rural counterparts. Students from capital city areas had significantly more negative views about the rural doctor role, especially related to workload, limited resources and isolation than students from rural and regional areas. Students entering medical school already have both positive and negative views about the life and work of a rural doctor. Those students from capital city areas have significantly more negative views despite being selected to enter a medical course with a rural focus based on their expressed rural perceptions. Further work is required to refine selection criteria and the year level experiences and learning opportunities which may positively influence student perceptions about rural medical practice to overcome early negative perceptions at the beginning of medical school.
75 FR 41695 - Rural Microentrepreneur Assistance Program; Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-19
... DEPARTMENT OF AGRICULTURE Rural Business-Cooperative Service 7 CFR Part 4280 RIN 0570-AA71 Rural Microentrepreneur Assistance Program; Correction AGENCY: Rural Business-Cooperative Service, USDA. ACTION... of rural microenterprises. This document has an incorrect definition of ``nonprofit entity...
77 FR 35657 - Information Collection Activity; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-14
... Information Collection Activity; Comment Request AGENCY: Rural Utilities Service, USDA. ACTION: Notice and... 35, as amended), the United States Department of Agriculture (USDA) Rural Development administers rural utilities programs through the Rural Utilities Service. The USDA Rural Development invites...
The changing rural environment and the relationship between health services and rural development.
Cordes, S M
1989-01-01
Author summarizes today's changing rural America and the challenges that health services researchers and policymakers face in relating the rural environment to the problems and possibilities of rural health services delivery. PMID:2917874
Application of the Rural Development Index to Analysis of Rural Regions in Poland and Slovakia
ERIC Educational Resources Information Center
Michalek, Jerzy; Zarnekow, Nana
2012-01-01
The main purpose of this research was to construct a multi-dimensional (composite) index measuring the overall level of rural development and quality of life in individual rural regions of a given EU country. In the Rural Development Index (RDI) the rural development domains are represented by hundreds of partial socio-economic, environmental,…
ERIC Educational Resources Information Center
McManus, Phil; Walmsley, Jim; Argent, Neil; Baum, Scott; Bourke, Lisa; Martin, John; Pritchard, Bill; Sorensen, Tony
2012-01-01
Many studies have highlighted the phenomenon of rural decline in parts of the developed world, summarised as a loss in agricultural employment leading to a decline in the number and size of rural settlements. This study of small towns in part of Australia's inland rural "heartland" employs the concepts of interactional rural community of…
ERIC Educational Resources Information Center
Hamilton, Vance E., Comp.
A State Task Force on Rural Health was formed (January 1973) by the State Rural Development Committee to identify and analyze major rural health problems in North Carolina and to recommend alleviation strategies. The Task Force submitted open-ended questionnaires to members of the County Rural Development Panels to secure their perceptions of…
"How to Be a Rural Man": Young Men's Performances and Negotiations of Rural Masculinities
ERIC Educational Resources Information Center
Bye, Linda Marie
2009-01-01
This paper is concerned with young rural men and how they "do" identity politics living in a rural area of Norway. Focusing on how masculinity and rurality are constructed and interrelated in young men's narratives of living in a remote community, it is identified that young rural men reproduce, negotiate and transform local discourses…
ERIC Educational Resources Information Center
Staihr, Brian
This first article in a series on telecommunications in rural America provides an overview of several key telecommunication issues facing rural regions. High speed data services known as broadband have the potential to make rural areas less isolated and improve the rural quality of life, but physical barriers, sparse population density, and few…
ERIC Educational Resources Information Center
Downey, Laura H.; Wheat, John R.; Leeper, James D.; Florence, Joseph A.; Boulger, James G.; Hunsaker, Matt L.
2011-01-01
Context: Over a decade ago, leaders in rural medical education established the Rural Medical Educators (RME) Group, an interest group within the National Rural Health Association, to support faculty in rural medical education programs. This group has convened an annual RME conclave since 2006. In 2008, this conclave convened 15 national leaders in…
ERIC Educational Resources Information Center
Erickson, Lance D.; Call, Vaughn R. A.; Brown, Ralph B.
2012-01-01
As rural communities undergo substantial demographic and economic changes, understanding the migration intentions and their antecedents of rural elderly persons becomes increasingly important. Using data drawn from a survey of adults from 24 rural Utah communities conducted in 2008, we examine whether rural residents 60 years of age or older plan…
Rural Runaways: Rurality and Its Implications for Services to Children and Young People Who Run Away
ERIC Educational Resources Information Center
Franks, Myfanwy; Goswami, Haridhan
2010-01-01
This article debates options for service provision to young rural runaways in the UK. Using data drawn from two national surveys and follow-on qualitative studies, the authors trace urban myths of rurality and their effects on runaway provision. The authors review models of rural refuge, systemic advocacy and mobile services for rural runaways.…
ERIC Educational Resources Information Center
Tieken, Mara Casey
2016-01-01
The college-going rates of rural students lag behind those of more urban students, a gap likely due, in part, to rural students' lower educational aspirations. These lower aspirations appear to be tied to the dilemma that higher education presents for many rural students: whether to remain in their rural home, working in traditional trades and…
ERIC Educational Resources Information Center
Rural America, Inc., Washington, DC.
Recommendations which emerged from the Second and Third National Conferences on Rural America are presented in this revised platform of principles and policy recommendations for rural America. Major goal of the document is to find practical solutions to problems facing rural people so that strategies of rural revitalization and action can be…
The Many Faces of Ephraim: In Search of A Functional Typology of Rural Areas.
ERIC Educational Resources Information Center
Whitaker, William H.
The literature of social work and rural sociology lacks conceptualization of the term "rural" and treats the term imprecisely. According to a 1960 survey, authors dealing with rural/urban differences do not agree on the attributes of "rural." However, if the rural concept is to be a useful analytical tool and guide to social work practice, its…
ERIC Educational Resources Information Center
Department of Agriculture Graduate School, Washington, DC.
This report addresses current economic conditions in rural America and offers recommendations about the role the United States Department of Agriculture (USDA) can play in providing rural development. The Task Force identifies issues for rural policy in the 1990's focusing on economic development. Current rural programs are described and…
Keeping School in Rural America: A New Paradigm for Rural Education and Community Development.
ERIC Educational Resources Information Center
Haas, Toni
This paper differentiates between the "old story" of rural education and the emerging "new story." It describes the tradition (old story) in which rural education is related to the local and national economies and lays out fragments of the new story, a paradigm that combines rural education and the rural economy in a way that strengthens them…
Pedagogy of the Rural: Implications of Size on Conceptualisations of Rural
ERIC Educational Resources Information Center
Walker-Gibbs, Bernadette; Ludecke, Michelle; Kline, Jodie
2015-01-01
This paper proposes a concept of Pedagogy of the Rural that draws together current rural education theory and practice to illustrate the complexities of rural space and place often overlooked in teacher education more broadly. We firstly examine notions of size, and then we explore how this impacts on the ways in which teachers in rural locations…
ERIC Educational Resources Information Center
Halaas, Gwen Wagstrom; Zink, Therese; Finstad, Deborah; Bolin, Keli; Center, Bruce
2008-01-01
Context: Founded in 1971 with state funding to increase the number of primary care physicians in rural Minnesota, the Rural Physician Associate Program (RPAP) has graduated 1,175 students. Third-year medical students are assigned to primary care physicians in rural communities for 9 months where they experience the realities of rural practice with…
Meeting Increasing Demands for Rural General Surgeons.
Mccarthy, Mary C; Bowers, Howard E; Campbell, Damon M; Parikh, Priti P; Woods, Randy J
2015-12-01
Dynamic assessment of the effective surgical workforce recommends 27,300 general surgeons in 2030; 2,525 more than are presently being trained. Rural shortages are already critical and there has been insufficient preparation for this need. A literature review of the factors influencing the choice of rural practice was performed. A systematic search was conducted of PubMed and the Web of Science to identify applicable studies in rural practice, surgical training, and rural general surgery. These articles were reviewed to identify the pertinent reports. The articles chosen for review are directed to four main objectives: 1) description of the challenges of rural practice, 2) factors associated with the choice of rural practice, 3) interventions to increase interest and preparation for rural practice, and 4) present successful rural surgical practice models. There is limited research on the factors influencing surgeons in the selection of rural surgery. The family practice literature suggests that physicians are primed for rural living through early experience, with reinforcement during medical school and residency, and retained through community involvement, and personal and professional satisfaction. However, more research into the factors drawing surgeons specifically to rural surgery, and keeping them in the community, is needed.
Del-1 Expression as a Potential Biomarker in Triple-Negative Early Breast Cancer.
Lee, Soo Jung; Lee, Jeeyeon; Kim, Wan Wook; Jung, Jin Hyang; Park, Ho Yong; Park, Ji-Young; Chae, Yee Soo
2018-01-01
A differential diagnostic role for plasma Del-1 was proposed for early breast cancer (EBC) in our previous study. We examined tumoral Del-1 expression and analyzed its prognostic impact among patients with EBC. Del-1 mRNA expression was assessed in breast epithelial and cancer cells. Meanwhile, the tumoral expression of Del-1 was determined based on tissue microarrays and immunohistochemistry results from 440 patients. While a high Del-1 mRNA expression was found in all the breast cancer cell lines, the expression was significantly higher in MDA-MB-231. Tumoral expression of Del-1 was also significantly associated with a negative expression of estrogen receptor or progesterone receptor, and low expression of Ki-67, particularly in the case of triple-negative breast cancer (TNBC) (p < 0.036). Furthermore, a correlation was found between Del-1 expression and an aggressive histological grade, nuclear mitosis, and polymorphism, suggesting a possible role in tumor progression. In the survival analysis, a worse distant disease-free survival trend was noted for the group overexpressing Del-1. While all the investigated breast cancer cell lines exhibited Del-1 expression, the expression rate and intensity were specifically prominent in TNBC. In addition, based on its relationship to an unfavorable histology and worse survival trend, Del-1 could act as a molecular target in TNBC patients. © 2018 S. Karger AG, Basel.
Braun, Thorsten; de Botton, Stéphane; Taksin, Anne-Laure; Park, Sophie; Beyne-Rauzy, Odile; Coiteux, Valérie; Sapena, Rosa; Lazareth, Anne; Leroux, Geneviève; Guenda, Khaled; Cassinat, Bruno; Fontenay, Michaela; Vey, Norbert; Guerci, Agnès; Dreyfus, François; Bordessoule, Dominique; Stamatoullas, Aspasia; Castaigne, Sylvie; Terré, Christine; Eclache, Virginie; Fenaux, Pierre; Adès, Lionel
2011-07-01
Isolated 20q deletion is common in MDS and considered of good prognosis, but no large series have been reported. We compared characteristics of 62 MDS patients with isolated del 20q, 36 patients with del 20q and other cytogenetic abnormalities, and 1335 MDS patients without del20q. Significant differences between MDS with isolated del 20q and patients without del 20q were lower platelet count (mean 144 vs. 196 G/l, p=0.005), lower marrow blast count (mean 3.9% vs. 5.6%, p=0.0008), and higher reticulocyte count (mean 72.5 vs. 51.7 G/l, p=0.04). Ten (16%) patients with isolated del 20q had Hb>12 g/dl and platelets <100 G/l, compared to 7.3% of patients without del 20q (p=0.025). Review of marrow slides of those 10 patients showed that could be readily identified as MDS prior to cytogenetics. Fourteen percent of patients with isolated del 20q progressed to AML compared to 11% with one and 24% with several additional abnormalities. Median survival was 54 months in patients with isolated del 20q, not reached and 12 months for del 20q with one and several additional abnormalities, respectively (p=0.035) confirming the favorable prognosis of del 20q without complex abnormalities. Copyright © 2011 Elsevier Ltd. All rights reserved.
Produccion Gaseosa del Cometa Halley: Erupciones Y Fotodisociacion del Radical OH
NASA Astrophysics Data System (ADS)
Silva, A. M.; Mirabel, I. F.
1990-11-01
RESUMEN:En este trabajo informamos la detecci6n de 20 erupciones en la li'nea de =18cm (1667MHz) del radical OH en el Cometa Halley.Las observaciones incluyen todos los monitoreos existentes y se extienden desde 120 dias antes del perihelio hasta 90 dias despues.Se detectan bruscos crecimientos en el flujo medido,hasta un factor 1O,seguidos por decaimientos lentos asociados con la fotodisociaci6n del OH. Se obtuvieron valores para el tiempo de vida fotoquimico del OH y del H2O basandose en el modelo desarrollado previamente por Silva(1988). Esos tiempos de vida estan de acuerdo con predicciones teoricas y con las observaciones en el Ultravioleta, y los resultados, los que son fuertemente dependientes de la velocidad heliocentrica del Coineta (variando hasta un factor 6), han sido calculados para varios rangos de velocidad entre +28 y -28 km/seg. Key wo'L :
McPhail, Deborah; Chapman, Gwen E; Beagan, Brenda L
2013-07-01
Resting on the notion that rural spaces are "food deserts," rural adolescents are increasingly regarded as a "problem population" in Western obesity narratives. Using qualitative data gleaned from interviews with 51 teenage participants from rural areas across Canada, this paper focuses on the ways in which obesity is constructed as a rural disease in the Canadian context, demonstrating in particular how discourses of food deserts and related rural obesity rely on classist imaginings of obesity as a working-class embodiment. The paper will further question the understanding of the rural as a food desert, showing the ways in which rural teens acquire fresh, healthy foods in part through an informal economy of food growing and sharing. Copyright © 2013 Elsevier Ltd. All rights reserved.
McAndrews, Carolyn; Beyer, Kirsten; Guse, Clare E; Layde, Peter
2016-12-01
Urban and rural places are integrated through economic ties and population flows. Despite their integration, most studies of road safety dichotomize urban and rural places, and studies have consistently demonstrated that rural places are more dangerous for motorists than urban places. Our study investigates whether these findings are sensitive to the definition of urban and rural. We use three different definitions of urban-rural continua to quantify and compare motor vehicle occupant fatality rates per person-trip and person-mile for the state of Wisconsin. The three urban-rural continua are defined by: (1) popular impressions of urban, suburban, and rural places using a system from regional economics; (2) population density; and (3) the intensity of commute flows to core urbanized areas. In this analysis, the three definitions captured different people and places within each continuum level, highlighting rural heterogeneity. Despite this heterogeneity, the three definitions resulted in similar fatality rate gradients, suggesting a potentially latent "rural" characteristic. We then used field observations of urban-rural transects to refine the definitions. When accounting for the presence of higher-density towns and villages in rural places, we found that low-density urban places such as suburbs and exurbs have fatality rates more similar to those in rural places. These findings support the need to understand road safety within the context of regional development processes instead of urban-rural categories. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Seung-Hwan; Kim, Dong-Young; Jing, Feifeng
Developmental endothelial locus-1 (Del-1) is an endogenous anti-inflammatory molecule that is highly expressed in the lung and the brain and limits leukocyte migration to these tissues. We previously reported that the expression of Del-1 is positively regulated by p53 in lung endothelial cells. Although several reports have implicated the altered expression of Del-1 gene in cancer patients, little is known about its role in tumor cells. We here investigated the effect of Del-1 on the features of human lung carcinoma cells. Del-1 mRNA was found to be significantly decreased in the human lung adenocarcinoma cell lines A549 (containing wild typemore » of p53), H1299 (null for p53) and EKVX (mutant p53), compared to in human normal lung epithelial BEAS-2B cells and MRC-5 fibroblasts. The decrease of Del-1 expression was dependent on the p53 activity in the cell lines, but not on the expression of p53. Neither treatment with recombinant human Del-1 protein nor the introduction of adenovirus expressing Del-1 altered the expression of the apoptosis regulators BAX, PUMA and Bcl-2. Unexpectedly, the adenovirus-mediated overexpression of Del-1 gene into the lung carcinoma cell lines promoted proliferation and invasion of the lung carcinoma cells, as revealed by BrdU incorporation and transwell invasion assays, respectively. In addition, overexpression of the Del-1 gene enhanced features of epithelial–mesenchymal transition (EMT), such as increasing vimentin while decreasing E-cadherin in A549 cells, and increases in the level of Slug, an EMT-associated transcription regulator. Our findings demonstrated for the first time that there are deleterious effects of high levels of Del-1 in lung carcinoma cells, and suggest that Del-1 may be used as a diagnostic or prognostic marker for cancer progression, and as a novel therapeutic target for lung carcinoma. - Highlights: • Developmental Endothelial Locus-1 (Del-1) expression is downregulated in human lung cancer cells. • Overexpression of the Del-1 gene potentiates proliferation and invasion of lung carcinoma cells. • Del-1 may be used as a diagnostic or prognostic marker for lung cancer progression.« less
ERIC Educational Resources Information Center
Walker, Sherry Freeland, Ed.
2001-01-01
This theme issue of "State Education Leader" contains eight articles on rural education. "The Rural Bellwether" (Kathy Christie) discusses declining enrollment in rural schools, rural problems with teacher shortages and special education funding, issues related to school size and school district size, and distance learning…
77 FR 26735 - Information Collection Activity; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-07
... AGENCY: Rural Utilities Service, USDA. ACTION: Notice and request for comments. SUMMARY: In accordance... Department of Agriculture (USDA) Rural Development administers rural utilities programs through the Rural Utilities Service (RUS). The USDA Rural Development invites comments on the following information...
Klotzsche - von Ameln, Anne; Cremer, Sebastian; Hoffmann, Jedrzej; Schuster, Peggy; Khedr, Sherif; Korovina, Irina; Troulinaki, Maria; Neuwirth, Ales; Sprott, David; Chatzigeorgiou, Antonios; Economopoulou, Matina; Orlandi, Alessia; Hain, Andreas; Zeiher, Andreas M.; Deussen, Andreas; Hajishengallis, George; Dimmeler, Stefanie; Chavakis, Triantafyllos; Chavakis, Emmanouil
2017-01-01
We have recently identified endothelial cell-secreted developmental endothelial locus-1 (Del-1) as an endogenous inhibitor of β2-integrin–dependent leukocyte infiltration. Del-1 was previously also implicated in angiogenesis. Here, we addressed the role of endogenously produced Del-1 in ischemia-related angiogenesis. Intriguingly, Del-1–deficient mice displayed increased neovascularization in two independent ischemic models (retinopathy of prematurity and hind-limb ischemia), as compared to Del-1–proficient mice. On the contrary, angiogenic sprouting in vitro or ex vivo (aortic ring assay) and physiological developmental retina angiogenesis were not affected by Del-1 deficiency. Mechanistically, the enhanced ischemic neovascularization in Del-1-deficiency was linked to higher infiltration of the ischemic tissue by CD45+ hematopoietic and immune cells. Moreover, Del-1-deficiency promoted β2-integrin–dependent adhesion of hematopoietic cells to endothelial cells in vitro, and the homing of hematopoietic progenitor cells and of immune cell populations to ischemic muscles in vivo. Consistently, the increased hind limb ischemia-related angiogenesis in Del-1 deficiency was completely reversed in mice lacking both Del-1 and the β2-integrin LFA-1. Additionally, enhanced retinopathy-associated neovascularization in Del-deficient mice was reversed by LFA-1 blockade. Our data reveal a hitherto unrecognized function of endogenous Del-1 as a local inhibitor of ischemia-induced angiogenesis by restraining LFA-1–dependent homing of pro-angiogenic hematopoietic cells to ischemic tissues. Our findings are relevant for the optimization of therapeutic approaches in the context of ischemic diseases. PMID:28447099
Rural medical education in Europe: the relevance of the Australian experience.
Hays, Richard B
2007-01-01
The drive to increase recognition of the different health care needs of rural communities has been more successful in North America and Australia than in Europe. This success has translated into political support for a range of education, workforce and service model initiatives that appear to be effective in providing a better prepared and supported healthcare workforce in rural communities, providing services through specifically developed delivery models, all with the aim of improving the quality of health care for rural people. The reasons for the differences between Europe and nations with greater success appear to relate to: the absence of a clear, shared definition of rurality across a very diverse group of nations within Europe, and a weaker coalition of interests advocating rural health issues. As a result, although very similar rural health issues are present in Europe, governments are not particularly supportive of initiatives aimed specifically at rural health and so rural medical education is much less well developed. This article explores how the rural health movement in Europe might build on success elsewhere to develop and successfully promote locally relevant models of rural medical education.
ERIC Educational Resources Information Center
Parmley, Fran, Ed.
This collection of conference papers covers various aspects of rural education in changing times. The conference focused on changes and innovations in rural education and on reasons why rural educators can be optimistic. The proceedings report includes brief papers and workshop summaries on topics ranging from rural public relations to…
ERIC Educational Resources Information Center
Lou, Jingjing
2011-01-01
Based on an ethnographic study in a rural middle school in Northwest China, the author explores how the transition of the rural countryside, specifically townization, has challenged the urban-rural dichotomy being reproduced in and by formal schooling. Rural students express criticism of the chaos, pollution, and corruption they have experienced…