[Not Available].

PubMed

Giner, Manel; Culebras, Jesús M; Meguid, Michael M

2016-03-01

En agosto de 1976, un joven llamado LeRoy cayó desde una cornisa fracturándose el fémur. Se sospechó una hemorragia interna importante. Durante una laparotomía se comprobó que todos los órganos internos estaban intactos y los cirujanos ortopédicos arreglaron la fractura. Treintadías después, LeRoy murió. Había comido poco; diariamente, tan solo había recibido tres litros de la glucosa, el equivalente a 510 calorías, por vía intravenosa. La glucosa fue insuficiente para satisfacer sus necesidades nutricionales, perdiendo más del 20% de su peso corporaldurante su estancia en el hospital. La causa de la muerte se debió a "desnutrición médicamente inducida". Mientras tanto, un artículo científico documentó que la prevalencia de desnutrición en los hospitales de Boston era del 44% y que la desnutrición en sí era un predictor de altas tasas de complicaciones y muerte.Como resultado, los médicos sensibilizados formaron una sociedad que creó programas de formación y alentó la formación de equipos de nutrición en los hospitales. La industria comercializó fórmulas de nutrición y catéteres. Las complicaciones en enfermos hospitalizados cayeron en picado, mientras que las tasas de supervivencia aumentaron. California aprobó una legislación para regular el soporte nutricional. Aunque la industria de la atención sanitaria reconoce la importancia de la nutrición en los cuidados al paciente, el Congreso no proporcionó apoyo fiscal para los equipos de nutrición. Como resultado, los hospitales disolvieron sus equipos de nutrición de reciente creación. La educación y las habilidades en nutrición disminuyeron, y las complicaciones hospitalarias y las tasas de mortalidad aumentaron de nuevo.

Influencia atmosférica en la rotación terrestre

NASA Astrophysics Data System (ADS)

Fernández, L. I.; Arias, E. F.; Brunini, C. A.

Las observaciones de los parámetros de la orientación terrestre han alcanzado en estos últimos años una exactitud sin precedentes gracias al uso de modernas técnicas de geodesia espacial. Estudios previos han establecido que las variaciones en la rotación terrestre con períodos iguales o menores que dos años obedecen a cambios en la circulación atmosférica global. Para estos períodos puede comprobarse que existe un gran acuerdo entre las fluctuaciones de la longitud del día (LOD) y los cambios del momento angular atmosférico terrestre (AAM). Sin embargo, no existe un acuerdo general acerca de las causas que provocan las variaciones de largo período de la rotación de la Tierra, también conocidas como ``variaciones decenales''. En nuestro análisis examinamos las correlaciones entre las variaciones de los valores de LOD y las fluctuaciones en la componente polar del momento angular atmosférico terrestre. Con este propósito utilizamos los siguientes juegos de datos: las series de AAM, estimado siguiendo la definición de Barnes et al.(1983) para 2825 días provientes del National Meteorological Center (NMC) y del European Centre for Medium Range Weather Forecast (ECMWF); y las series de LOD que contienen valores alisados espaciados a intervalos de un día elaborados por el International Earth Rotation Service (IERS). Mostraremos que para los cambios anuales e interanuales en la rotación de la Tierra la influencia atmosférica es asombrosa, mientras que, tanto en las escalas temporales más grandes y como en las más pequeñas, ambas series, geodésica y atmosférica, parecen diverger aún cuando poseemos observaciones obtenidas con las técnicas más modernas al presente.

CONTAMINACIÓN AMBIENTAL, VARIABILIDAD CLIMÁTICA Y CAMBIO CLIMÁTICO: UNA REVISIÓN DEL IMPACTO EN LA SALUD DE LA POBLACIÓN PERUANA

PubMed Central

Gonzales, Gustavo F.; Zevallos, Alisson; Gonzales-Castañeda, Cynthia; Nuñez, Denisse; Gastañaga, Carmen; Cabezas, César; Naeher, Luke; Levy, Karen; Steenland, Kyle

2015-01-01

RESUMEN El presente artículo es una revisión sobre la contaminación del agua, el aire y el efecto del cambio climático en la salud de la población peruana. Uno de los principales contaminantes del aire es el material particulado menor de 2,5 μ (PM 2,5), en la ciudad de Lima, anualmente 2300 muertes prematuras son atribuibles a este contaminante. Otro problema es la contaminación del aire domiciliario por el uso de cocinas con combustible de biomasa, donde la exposición excesiva a PM 2,5 dentro de las casas es responsable de aproximadamente 3000 muertes prematuras anuales entre adultos, con otro número desconocido de muertes entre niños debido a infecciones respiratorias. La contaminación del agua tiene como principales causas los desagües vertidos directamente a los ríos, minerales (arsénico) de varias fuentes, y fallas de las plantas de tratamiento. En el Perú, el cambio climático puede impactar en la frecuencia y severidad del fenómeno de El Niño oscilación del sur (ENSO) que se ha asociado con un incremento en los casos de enfermedades como cólera, malaria y dengue. El cambio climático incrementa la temperatura y puede extender las áreas afectadas por enfermedades transmitidas por vectores, además de tener efecto en la disponibilidad del agua y en la contaminación del aire. En conclusión, el Perú, pasa por una transición de factores de riesgo ambientales, donde coexisten riesgos tradicionales y modernos, y persisten los problemas infecciosos y crónicos, algunos de los cuales se asocian con problemas de contaminación de agua y de aire. PMID:25418656

El uso de la neuromodulación para el tratamiento del temblor

PubMed Central

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

Les déformations eburnéennes de l'unité birrimienne de la comoé (côte d'ivoire)

NASA Astrophysics Data System (ADS)

Vidal, M.

The analysis of Eburnean strain fields in the Upper (?) Birrimian Comoé Unit shows four great stages of tectogenesis: an early cleavage subparallel to stratification which results from synkinematic granitoïd intrusions; a folding (N40°E to N60°E); a transcurrent faulting period, essentially ductile N-S sinistral; N120°E schistosity, and a N110°E transcurrent ductile sinistral (?) faulting phase. The importance of the sinistral N-S faulting system and, to a lesser extent, the N120°E schistosity direction, is shown. The probable rôle of these directions (particularly N-S) from Liberian to Upper Cretaceous is shown by the within-plate tectonic occurrences in the West-African craton.

[Not Available].

PubMed

Corella Aznar, Elena Guadalupe; Ayerza Casas, Ariadna; Samper Villagrasa, Pilar; Rodríguez Vigil, Carmen; Jiménez Montañés, Lorenzo; Calvo Escribano, Carlota; Labarta Aizpun, José Ignacio

2016-06-30

Introducción: los supervivientes de leucemia aguda (LA) infantil presentan un riesgo incrementado de alteraciones metabólicas y cardiovasculares que aumentan su morbimortalidad a largo plazo.Objetivo: estimar la prevalencia de obesidad, resistencia a la insulina, dislipemia e hipertensión arterial como factores de riesgo cardiometabólico (FRCM) en un grupo de supervivientes de LA infantil, y analizar las posibles causas asociadas a su desarrollo.Material y métodos: estudio observacional retrospectivo en 47 supervivientes de LA tratados en un periodo de 4 años, que recibieron seguimiento durante 10 años.Resultados: el 40% de los participantes presentaron al menos un FRCM durante el seguimiento, siendo la dislipemia (aumento LDL) el más frecuente (38,3%), seguido de obesidad/sobrepeso (31,9%) y HTA sistólica (23,4%). El sexo femenino se estableció como factor de riesgo parael desarrollo de todos ellos (RR 1,6; RR 3,16; RR 1,69; p < 0,05). Ningún superviviente desarrolló diabetes mellitus, pero sí resistencia a la insulina el 19,4%. Los pacientes con leucemias de peor pronóstico presentaron mayor riesgo de desarrollar obesidad, resistencia a la insulina y aumento de LDL (RR 3,56; RR 4,08; RR 2,53; p < 0,05). Los pacientes tratados con trasplante de progenitores hematopoyéticos presentaron mayor riesgo de obesidad, aumento de LDL e HTA sistólica (RR 2,86; RR 2,39; RR 3,12; p<0,05). La radioterapia se asoció de igual modo con un incremento de resistencia a la insulina e hipertensión arterial sistólica (RR 2,47; RR 2,53; p < 0,05).Conclusiones: existe un aumento en la prevalencia de obesidad/sobrepeso, dislipemia, resistencia a la insulina y alteración de la tensión arterial sistólica en supervivientes de leucemia aguda infantil a lo largo del tiempo, especialmente en aquellos con enfermedades y tratamientos más agresivos.

Do Allergies Cause Asthma?

MedlinePlus

... Safe Videos for Educators Search English Español Do Allergies Cause Asthma? KidsHealth / For Parents / Do Allergies Cause ... Las alergias son la causa del asma? Do Allergies Cause Asthma? Allergies don't cause asthma. But ...

Perfis de temperatura eletrônica em regiões HII

NASA Astrophysics Data System (ADS)

Copetti, M. V. F.

2003-08-01

As flutuações de temperatura eletrônica em regiões HII, inicialmente propostas para explicar as discrepâncias entre os valores de temperatura obtidos por diferentes métodos, têm sido apontadas como a causa mais provável das enormes diferenças encontradas entre as abundâncias químicas medidas através de linhas excitadas colisionalmente e de linhas de recombinação. Recentemente têm sido reportadas tentativas de detecção e quantificação diretas das flutuações de temperatura eletrônica através de medidas ponto a ponto, obtidas por meio de espectroscopia de fenda longa, das razões de linhas [OIII]l4263/l5007 e [NII]l5755/l6584, principais sensores de temperatura. Neste trabalho, utilizamos o código numérico de fotoionização Cloudy para avaliar a confiabilidade desse procedimento. Concluímos que, para valores de densidade eletrônica e de temperatura efetiva da estrela ionizante típicos das regiões HII, os perfis superficiais de temperatura obtidos via medidas do sensor [OIII]l4263/l5007 são bons traçadores dos gradientes internos de temperatura eletrônica. Já os perfis de temperatura eletrônica medidos por meio da razão [NII]l5755/l6584 não reproduzem os gradientes verdadeiros de temperatura.

Terapia fibrinolítica sistêmica no tromboembolismo pulmonar

PubMed Central

Ceresetto, José Manuel; Marques, Marcos Arêas

2017-01-01

Resumo O tromboembolismo pulmonar permanece como um grande desafio terapêutico para os médicos especialistas, pois, apesar de todo investimento e desenvolvimento em seu diagnóstico, profilaxia e tratamento, essa condição continua sendo a principal causa de morte evitável em ambiente hospitalar. Ainda restam muitas dúvidas em relação a qual perfil de paciente vai se beneficiar de fato da terapia fibrinolítica sistêmica, sem ficar exposto a um grande risco de sangramento. A estratificação de risco e a avaliação do prognóstico do evento, através de escores clínicos de insuficiência ventricular direita, marcadores de dilatação e disfunção do ventrículo direito e avaliação da massa trombótica, associados ou de forma isolada, são ferramentas que podem auxiliar na identificação do paciente que irá se beneficiar dessa terapia. Os únicos consensos em relação à terapia fibrinolítica no tratamento do tromboembolismo pulmonar são: não deve ser indicada de forma rotineira; nenhum dos escores ou marcadores, isoladamente, devem justificar seu uso; e os pacientes com instabilidade hemodinâmica são os mais beneficiados. Além disto, deve-se avaliar cada caso em relação ao risco de sangramento, especialmente no sistema nervoso central. PMID:29930636

[Not Available].

PubMed

Norte Navarro, Aurora Isabel; Sansano Perea, Miriam; Martínez Sanz, José Miguel; Sospedra López, Isabel; Hurtado Sánchez, José Antonio; Ortiz Moncada, Rocío

2016-06-30

Introducción y objetivos: las enfermedades cardiovasculares (ECV) son la principal causa de muerte mundial, por ello el objetivo de este estudio es analizar los factores de riesgo de ECV en los trabajadores de la Universidad de Alicante.Material y métodos: estudio transversal descriptivo. Muestra aleatoria (n = 124), 46,6% mujeres y 53,4% hombres, de edades entre 25-68 años. Recogida de datos mediante cuestionario online autocumplimentado. sociodemográficas, peso y talla autorreferidos, consumo de tabaco, actividad física, consumo diario de aceite de oliva, hortalizas-verduras, mantequilla-margarina-nata y consumo semanal de repostería comercial y frutos secos. Se realizó un análisis descriptivo con el paquete estadístico SPSS 19.0.Resultados: el 12% de mujeres y el 10,5% de los hombres mayores de 44 años presentan obesidad; además, el 32% de mujeres y el 23,7% de los hombres no realizan actividad física. Consume aceite de oliva a diario el total de la muestra a estudio.Conclusión: los hábitos alimentarios de los estudiados se asemejan a los patrones dietéticos mediterráneos considerados saludables. Destacar el cumplimiento de las recomendaciones de consumo de aceite de oliva y la realización de actividad física habitual como protectores de las ECV. El entorno laboral de la población estudiada favorece unos hábitos saludables.

Intellectual Disability

MedlinePlus

... discapacidad intelectual puede ser la consecuencia de un problema que comienza antes de que el niño nazca ... causa puede ser una lesión, enfermedad o un problema en el cerebro. En muchos niños no se ...

A bone tissue engineering strategy based on starch scaffolds and bone marrow cells cultured in a flow perfusion bioreactor

NASA Astrophysics Data System (ADS)

Gomes, Maria Manuela Estima

A Engenharia de Tecidos e uma area cientifica em continua expansao. Os desenvolvimentos conseguidos por esta area tem contribuido significativamente para diversos avancos no campo da Medicina Regenerativa. Esta ciencia interdisciplinar combina os conhecimentos de diversas outras areas, tao distintas como a Engenharia de Materiais e a Biologia, com o objectivo de desenvolver substitutos sinteticos para tecidos humanos. Para se atingir este objectivo utilizam-se, de uma forma generica, combinacoes especificas de celulas e de um material de suporte tridimensional com propriedades adequadas, gerando um material hibrido cujas caracteristicas podem ainda ser moduladas atraves do sistema de cultura usado. A presente tese e centrada no desenvolvimento de estrategias de engenharia de tecido osseo baseadas na cultura in vitro de celulas previamente "semeadas" num suporte tridimensional ("scaffold"). Esta estrategia permite que as celulas adiram ao suporte, proliferem e segreguem matriz extracelular especifica do tecido osseo, ate se obter um substituto artificial funcional com caracteristicas do tecido original, que pode finalmente ser transplantado para tratar o defeito em causa. Para que uma estrategia deste tipo seja bem sucedida, pelo menos tres componentes fundamentais devem ser cuidadosamente estudados: o material de suporte (scaffold), as celulas a usar e o sistema de cultura in vitro. Dai que os principais objectivos desta tese estejam relacionados com estes tres aspectos, nomeadamente: • Desenvolvimento de scaffolds biodegradaveis a partir de polimeros a base de amido de milho que induzam a adesao e proliferacao celular e que apresentem propriedades adequadas, tais como a porosidade e interconectividade entre poros, de forma a proporcionar um ambiente que favoreca o desenvolvimento in vitro de um material hibrido com caracteristicas similares ao osso humano. • Estudo da utilizacao de celulas da medula ossea como uma potencial fonte de celulas para engenharia do tecido osseo, uma vez que estas celulas podem ser facilmente recolhidas do proprio paciente a tratar por metodos nao-invasivos (bioppsia) e em quantidades suficientes. Alem disso, tratando-se de uma fonte de celulas autologas (obtidas do proprio paciente) permitem evitar os riscos de transmissao de doencas contagiosas e/ou de rejeicao pelo sistema imunologico. • Estudo da influencia das condicoes de cultura in vitro geradas por um bioreactor de perfusao (em comparacao com os metodos tradicionais de cultura em condicoes estaticas) no desenvolvimento dos materiais hibridos, compostos pelas celulas e scaffolds, assim como as interaccoes do ambiente proporcionado por este sistema de cultura com as diferentes estruturas/arquitecturas e porosidades dos scaffolds utilizados. Estes objectivos convergem para o objectivo geral desta tese que consistiu no desenvolvimento de uma terapia de engenharia do tecido osseo alternativa as existentes e com potencial para vir a ser posteriormente utilizada na pratica clinica. Este objectivo foi avaliado atraves do estudo da funcionalidade dos materiais hibridos obtidos em diferentes condicoes de cultura in vitro (e utilizando diferentes scaffolds), partindo do principio que o sistema de perfusao poderia eventualmente superar as limitacoes de difusao tipicas dos sistema de cultura estatica e simultaneamente proporcionar estimulos mecânicos as celulas, semelhantes aos encontrados em condicoes fisiologicas. (Abstract shortened by ProQuest.).

Efeitos do binarismo não resolvido na determinação da função de massa de aglomerados

NASA Astrophysics Data System (ADS)

Kerber, L. O.; Santiago, B. X.

2003-08-01

Através de simulações numéricas buscamos quantificar os efeitos que o binarismo não resolvido causa na determinação da função de massa (MF) de aglomerados estelares. Geramos diagramas cor-magnitude (CMDs) artificiais simulando uma população única, caracterizada por estrelas de mesma idade e composição quí mica, com uma fração de binárias não resolvidas e distribuição em massa das estrelas dada por uma MF do tipo lei de potência. A presença de pares de estrelas não resolvidos faz com que a MF obtida da função de luminosidade (LF) tenha a têndencia de ser mais plana do que a MF que gerou o CMD artificial. Propomos um tratamento de correção para tal efeito. Outro efeito relacionado diz respeito ao alargamento do CMD, que apresenta-se como um indicador do número total de estrelas no domí nio de baixas massas (m < 0.6M¤). Todos os resultados acima possuem uma forte dependência com os erros fotométricos e estão baseados na hipótese de que ambas estrelas do par não resolvido são sorteadas de uma mesma MF de forma independente. O objetivo final é aplicarmos o tratamento aqui desenvolvido para implementarmos a análise da nossa amostra de aglomerados ricos da Grande Nuvem de Magalhães.

Darwin, Hume, Morgan, and the verae causae of psychology.

PubMed

Clatterbuck, Hayley

2016-12-01

Charles Darwin and C. Lloyd Morgan forward two influential principles of cognitive ethological inference that yield conflicting results about the extent of continuity in the cognitive traits of humans and other animals. While these principles have been interpreted as reflecting commitments to different senses of parsimony, in fact, both principles result from the same vera causa inferential strategy, according to which "We ought to admit no more causes of natural things, than such as are both true and sufficient to explain their appearances". Instead, the conflict stems from Darwin's and Morgan's views about the true causes of human psychology. Darwin holds a thoroughly Humean philosophy of the human mind, from which he infers significant continuity between human and animal minds. In contrast, Morgan argues that Humean cognitive mechanisms cannot account for a class of uniquely human behaviors, and therefore, he concludes that there is a significant discontinuity between human and animal cognition. This historical debate is informative for current controversies in comparative psychology. Copyright © 2016 Elsevier Ltd. All rights reserved.

What Causes Hiccups?

MedlinePlus

... Español What Causes Hiccups? KidsHealth / For Kids / What Causes Hiccups? Print en español ¿Cuál es la causa del hipo? "Hic!" You've just hiccuped for what seems like the tenth time since you finished your big dinner. Wonder where these funny noises are coming ...

Honoris Causa

ERIC Educational Resources Information Center

Cronin, Blaise

2002-01-01

A reasonable estimate puts the number of living American holders of honorary degrees at about 150,000. This inflated figure and a general lack of seriousness--Kermit the Frog, for instance, delivered the commencement address at Southampton College in 1996--trouble the author of this article. He suggests that the practice might somehow be adjusted…

La Causa Chicana. The Movement for Justice.

ERIC Educational Resources Information Center

Mangold, Margaret M., Ed.

The intent of this book is to present information about Chicanos to social workers and members of other helping professions so they may become involved in the Mexican Americans' movement to obtain first-class citizenship. Articles reflect the perspectives of persons working in various settings, geographical regions, and disciplines. Some of the…

Extremist Media and the Rise of Terrorism: The Argentine Case.

ERIC Educational Resources Information Center

Day, J. Laurence

In the 20 months that Isabel Peron served as the first female chief of state of a South American country, the mass media in Argentina underwent extreme stress. The Montoneros, a militant leftist organization, called for mass demonstrations against the orthodox Peronist people in their tabloid "La Causa Peronista." The tabloid's…

Pleuroparenchymal fibroelastosis: report of two cases in Brazil.

PubMed

Gomes, Paula Silva; Shiang, Christina; Szarf, Gilberto; Coletta, Ester Nei Aparecida Martins; Pereira, Carlos Alberto de Castro

2017-01-01

Pleuroparenchymal fibroelastosis (PPFE) is a rare lung disease. It can be idiopathic or associated with any one of various conditions. To our knowledge, this is the first report of two cases of PPFE in Brazil. Our first patient presented with pleural and subpleural fibrosis in the upper lobes; a spiculated nodule in the left upper lobe; and a mild reticular pattern in the lower lobes. Surgical lung biopsy revealed PPFE in the upper lobes, including the nodule, and unclassified interstitial pneumonia in the left lower lobe. Our second patient had a history of exposure to domestic birds, indicating a risk of hypersensitivity pneumonitis, and presented with advanced lung disease, predominantly in the upper lobes, together with subpleural fibrosis.That patient underwent lung transplantation. In the explant specimen, PPFE and granulomas were identified, suggesting hypersensitivity pneumonitis as an associated cause. RESUMO A fibroelastose pleuroparenquimatosa (FEPP) é uma doença pulmonar rara, podendo ser idiopática ou associada a diversas condições. Pelo que sabemos, este é o primeiro relato de dois casos de FEPP no Brasil. Nosso primeiro paciente apresentava fibrose pleural e subpleural nos lobos superiores, um nódulo espiculado no lobo superior esquerdo e um padrão reticular discreto nos lobos inferiores. A biópsia pulmonar cirúrgica demonstrou FEPP nos lobos superiores, incluindo no nódulo, e pneumonia intersticial não classificada no lobo inferior esquerdo. Nosso segundo paciente tinha história de exposição a aves domésticas, indicando um risco de pneumonite de hipersensibilidade, e doença pulmonar avançada predominando em lobos superiores, com fibrose subpleural. Esse paciente foi submetido a transplante pulmonar. No espécime do explante, FEPP e granulomas foram identificados, sugerindo pneumonite de hipersensibilidade como causa associada.

PubMed

Müller Velázquez, Lucía; Bobadilla, Fernando; Novosak, Marina; Cortese, Iliana; Laczeski, Margarita

2018-03-20

Streptococcus agalactiae (SGB) es causa de infecciones severas en menores de tres meses. Meningitis, neumonía y sepsis son los principales cuadros en estos niños. Estas infecciones se encuentran entre las más graves que puede sufrir un individuo en sus primeras doce horas de vida. El niño adquiere la infección por transmisión vertical de la madre colonizada. Para prevenir la enfermedad neonatal se recomienda penicilina como droga de elección en la profilaxis intraparto (PIP) en embarazadas colonizadas. Sin embargo, actualmente se han detectado cepas con sensibilidad disminuida a penicilina por lo que resulta importante realizar la vigilancia de la sensibilidad al mismo para asegurar su utilidad durante la profilaxis. El objetivo de este trabajo fue determinar la sensibilidad a penicilina en cepas de SGB recuperados de mujeres embarazadas de 35-37 semanas de gestación. Se estudiaron 96 aislamientos y se determinó la sensibilidad por método epsilométrico Etest® (LIOFILCHEM, Italia), siguiendo las recomendaciones del Clinical Laboratory Standards Institute (CLSI). Se obtuvo la Concentración Inhibitoria Mínima (CIM) para cada aislamiento bacteriano. El 100% (96) de las cepas estudiadas fue sensible a penicilina con valores de CIM comprendidos entre 0,012 y 0,094 µg mL-1. Estos resultados indican que penicilina sigue siendo el antimicrobiano de elección durante la profilaxis intraparto, para la prevención de la enfermedad neonatal causada por SGB en nuestra región. Se destaca la importancia de la vigilancia epidemiológica de la sensibilidad a penicilina y a otros antimicrobianos para alertar sobre nuevos mecanismos de resistencia y adecuar estrategias de tratamiento.

[Death of Napoleon Bonaparte].

PubMed

Camici, M

2003-06-01

The causa mortis of Napoleon Bonaparte has been vexata quaestio for a long time. The author tries to outline a picture of Napoleon from a sanitary point of view. From the report of doctor Francesco Antonmarchi who performed the autopsy, the author tries to understans the cause of death: gastric perforation due to malignant ulcer and subsequent peritonitis with pulmonary tubercolosis.

Cesar Chavez and La Causa: Books for Children and Teenagers.

ERIC Educational Resources Information Center

Garza de Cortes, Oralia

1995-01-01

Evaluates biographies of Cesar Chavez for children and teenagers and provides descriptions of recent books on the children of migrant farm workers. The books, mostly published in the 1990s, cover Chavez's rise as a farm worker activist and include several new works that address the social history of Chavez and the farm workers' struggle. (GR)

El Plan de Santa Barbara; A Chicano Plan for Higher Education.

ERIC Educational Resources Information Center

Chicano Coordinating Council on Higher Education, Santa Barbara, CA.

Published by La Causa Publications, the document is a Chicano plan for higher education in the universities and colleges in California. The manifesto found in the booklet states that "the self-determination of our community is now the only acceptable mandate for social and political action; it is the essence of Chicano commitment....Chicanos…

Revista de Saúde Pública in scientific publications on Violence and Health (1967-2015).

PubMed

Schraiber, Lilia Blima; Barros, Claudia; d'Oliveira, Ana Flávia Pires Lucas; Peres, Maria Fernanda Tourinho

2016-11-10

This article retrieved the publications from the Revista de Saúde Pública journal (from 1967 to 2015) on violence and health, on the SciELO and PubMed bases, by searching for the terms "violence", "suicide", "aggression", "bullying", and "external causes", registered in any part of the text. We found 130 articles (the first one published in 1974). We observed: increase of publications over time, with decrease in the last five years; similar production volume in lethal and non-lethal violence; later publication of the latter; few studies in qualitative research; mostly descriptive production; and visualization of the problem more by the acts than by contexts or motivations and aggressors. Social markers were little approached, appearing, from largest to smallest frequency, social class, gender, race/ethnicity, and generation. Human rights were little used and only recently used as analytical framework, connected more to gender than to social class. Although Revista de Saúde Pública has registered the theme in its publications, consolidating it as scientific production line, there is still great explanatory theoretical rarefaction and little intersectionality between violence, social inequalities, and human rights. RESUMO A produção da Revista de Saúde Pública (de 1967 até 2015) sobre violência e saúde foi recuperada nas bases SciELO e PubMed utilizando-se os termos "violência", "suicídio", "agressões", "bullying" e "causas externas", registrados em qualquer parte do texto. Foram encontrados 130 artigos (o primeiro deles publicado em 1974). Constatou-se: aumento das publicações no tempo, com decréscimo nos últimos cinco anos; volume similar de produção em violência letal e não letal; publicação mais tardia desta última; poucos estudos em pesquisa qualitativa; produção majoritariamente descritiva; e visibilização do problema, mais pelos atos que pelos contextos ou motivações e agressores. Os marcadores sociais foram pouco tematizados, aparecendo da maior para a menor frequência, classe social, gênero, raça/etnia e geração. Direitos humanos foi pouco, e apenas recentemente, usado como referencial analítico, conectado mais ao gênero do que à classe social. Embora a Revista de Saúde Pública tenha inscrito o tema em suas publicações, consolidando-o como linha de produção científica, há, ainda, grande rarefação teórica explicativa e pouca interseccionalidade entre violência, desigualdades sociais e direitos humanos.

Influence of H 2O and H 2S on the composition, activity, and stability of sulfided Mo, CoMo, and NiMo supported on MgAl 2O 4 for hydrodeoxygenation of ethylene glycol

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

Dabros, Trine Marie Hartmann; Gaur, Abhijeet; Pintos, Delfina Garcia

Here in this work, density functional theory (DFT), catalytic activity tests, and in-situ X-ray absorption spectroscopy (XAS) was performed to gain detailed insights into the activity and stability of MoS 2, Ni-MoS 2, and Co-MoS 2 catalysts used for hydrodeoxygenation (HDO) of ethylene glycol upon variation of the partial pressures of H 2O and H 2S. The results show high water tolerance of the catalysts and highlight the importance of promotion and H 2S level during HDO. DFT calculations unraveled that the active edge of MoS 2 could be stabilized against SO exchanges by increasing the partial pressure of Hmore » 2S or by promotion with either Ni or Co. The Mo, NiMo, and CoMo catalysts of the present study were all active and fairly selective for ethylene glycol HDO at 400 °C, 27 bar H 2, and 550–2200 ppm H 2S, and conversions of ≈50–100%. The unpromoted Mo/MgAl 2O 4 catalyst had a lower stability and activity per gram catalyst than the promoted analogues. The NiMo and CoMo catalysts produced ethane, ethylene, and C1 cracking products with a C 2/C 1 ratio of 1.5–2.0 at 550 ppm H 2S. This ratio of HDO to cracking could be increased to ≈2 at 2200 ppm H 2S which also stabilized the activity. Removing H 2S from the feed caused severe catalyst deactivation. Both DFT and catalytic activity tests indicated that increasing the H 2S concentration increased the concentration of SH groups on the catalyst, which correspondingly activated and stabilized the catalytic HDO performance. In-situ XAS further supported that the catalysts were tolerant towards water when exposed to increasing water concentration with H2O/H2S ratios up to 300 at 400–450 °C. Raman spectroscopy and XAS showed that MoS2 was present in the prepared catalysts as small and highly dispersed particles, probably owing to a strong interaction with the support. Linear combination fitting (LCF) analysis of the X-ray absorption near edge structure (XANES) spectra obtained during in-situ sulfidation showed that Ni was sulfided faster than Mo and CoMo, and that Mo was sulfided faster when promoted with Ni. Extended X-ray absorption fine structure (EXAFS) results showed the presence of MoS 2 in all sulfided catalysts. Lastly, sulfided CoMo was present as a mixture of CoMoS and Co 9S 8, whereas sulfided NiMo was present as NiMoS.« less

Influence of H 2O and H 2S on the composition, activity, and stability of sulfided Mo, CoMo, and NiMo supported on MgAl 2O 4 for hydrodeoxygenation of ethylene glycol

DOE PAGES

Dabros, Trine Marie Hartmann; Gaur, Abhijeet; Pintos, Delfina Garcia; ...

2017-12-10

Here in this work, density functional theory (DFT), catalytic activity tests, and in-situ X-ray absorption spectroscopy (XAS) was performed to gain detailed insights into the activity and stability of MoS 2, Ni-MoS 2, and Co-MoS 2 catalysts used for hydrodeoxygenation (HDO) of ethylene glycol upon variation of the partial pressures of H 2O and H 2S. The results show high water tolerance of the catalysts and highlight the importance of promotion and H 2S level during HDO. DFT calculations unraveled that the active edge of MoS 2 could be stabilized against SO exchanges by increasing the partial pressure of Hmore » 2S or by promotion with either Ni or Co. The Mo, NiMo, and CoMo catalysts of the present study were all active and fairly selective for ethylene glycol HDO at 400 °C, 27 bar H 2, and 550–2200 ppm H 2S, and conversions of ≈50–100%. The unpromoted Mo/MgAl 2O 4 catalyst had a lower stability and activity per gram catalyst than the promoted analogues. The NiMo and CoMo catalysts produced ethane, ethylene, and C1 cracking products with a C 2/C 1 ratio of 1.5–2.0 at 550 ppm H 2S. This ratio of HDO to cracking could be increased to ≈2 at 2200 ppm H 2S which also stabilized the activity. Removing H 2S from the feed caused severe catalyst deactivation. Both DFT and catalytic activity tests indicated that increasing the H 2S concentration increased the concentration of SH groups on the catalyst, which correspondingly activated and stabilized the catalytic HDO performance. In-situ XAS further supported that the catalysts were tolerant towards water when exposed to increasing water concentration with H2O/H2S ratios up to 300 at 400–450 °C. Raman spectroscopy and XAS showed that MoS2 was present in the prepared catalysts as small and highly dispersed particles, probably owing to a strong interaction with the support. Linear combination fitting (LCF) analysis of the X-ray absorption near edge structure (XANES) spectra obtained during in-situ sulfidation showed that Ni was sulfided faster than Mo and CoMo, and that Mo was sulfided faster when promoted with Ni. Extended X-ray absorption fine structure (EXAFS) results showed the presence of MoS 2 in all sulfided catalysts. Lastly, sulfided CoMo was present as a mixture of CoMoS and Co 9S 8, whereas sulfided NiMo was present as NiMoS.« less

Evolution of three tandem copies of the interleukin-1 receptor-like 1 gene in salmonid fish and their contribution to rainbow trout bacterial cold water disease resistant phenotype

USDA-ARS?s Scientific Manuscript database

Rainbow trout exhibit extensive phenotypic variation in innate disease resistance. Five generations of family based selection has resulted in rainbow trout lines with either increased or reduced survival following exposure to the gram-negative bacterium, Flavobacterium psychrophilum (Fp), the causa...

3 CFR 8953 - Proclamation 8953 of March 29, 2013. Cesar Chavez Day, 2013

Code of Federal Regulations, 2014 CFR

2014-01-01

..., Cesar Chavez knew hard work and hardship from an early age. He labored long hours for little pay, taking... rallied a generation of workers around “La Causa,” marching and fasting and boycotting for fair pay and... attention to his cause, he received a telegram from Dr. Martin Luther King, Jr. “As brothers in the fight...

Response to Johannsen, Rump, and Linder's Penetrating a wall of introspection: a critical attrition analysis

NASA Astrophysics Data System (ADS)

Rushton, Gregory T.; Criswell, Brett A.

2013-03-01

In Penetrating a Wall of Introspection: A Critical Attrition Analysis, Johannsen, Rump, and Linder strive to give a voice to those whose thoughts might otherwise be unheard: students representing the casualties in the conflict surrounding the practices of STEM education, specifically those in the field of physics. Beyond giving those students a voice, they try to filter out and amplify a message that the seven individuals themselves may not have recognized: that the cause of their struggles in their physics programs might not be something innate ( causa materialis in the authors' framework), but might be found outside the individuals ( causa efficiens in the authors' framework). In our response, we attempt to extend the conversation regarding the issues these authors have raised by (1) considering the conditions within the physics community that might exacerbate this situation and (2) exploring from a different perspective the nature of the discourses that will either perpetuate or ameliorate such circumstances. In so doing we seek to provide a more holistic description of the features of the educational system that help to construct the wall of introspection and that might, in turn, be redressed in order to help tear it down—and positively impact attrition rates.

The role of predictive uncertainty in the operational management of reservoirs

NASA Astrophysics Data System (ADS)

Todini, E.

2014-09-01

The present work deals with the operational management of multi-purpose reservoirs, whose optimisation-based rules are derived, in the planning phase, via deterministic (linear and nonlinear programming, dynamic programming, etc.) or via stochastic (generally stochastic dynamic programming) approaches. In operation, the resulting deterministic or stochastic optimised operating rules are then triggered based on inflow predictions. In order to fully benefit from predictions, one must avoid using them as direct inputs to the reservoirs, but rather assess the "predictive knowledge" in terms of a predictive probability density to be operationally used in the decision making process for the estimation of expected benefits and/or expected losses. Using a theoretical and extremely simplified case, it will be shown why directly using model forecasts instead of the full predictive density leads to less robust reservoir management decisions. Moreover, the effectiveness and the tangible benefits for using the entire predictive probability density instead of the model predicted values will be demonstrated on the basis of the Lake Como management system, operational since 1997, as well as on the basis of a case study on the lake of Aswan.

Physical Stress Echocardiography: Prediction of Mortality and Cardiac Events in Patients with Exercise Test showing Ischemia.

PubMed

Araujo, Ana Carla Pereira de; Santos, Bruno F de Oliveira; Calasans, Flavia Ricci; Pinto, Ibraim M Francisco; Oliveira, Daniel Pio de; Melo, Luiza Dantas; Andrade, Stephanie Macedo; Tavares, Irlaneide da Silva; Sousa, Antonio Carlos Sobral; Oliveira, Joselina Luzia Menezes

2014-11-01

Background: Studies have demonstrated the diagnostic accuracy and prognostic value of physical stress echocardiography in coronary artery disease. However, the prediction of mortality and major cardiac events in patients with exercise test positive for myocardial ischemia is limited. Objective: To evaluate the effectiveness of physical stress echocardiography in the prediction of mortality and major cardiac events in patients with exercise test positive for myocardial ischemia. Methods: This is a retrospective cohort in which 866 consecutive patients with exercise test positive for myocardial ischemia, and who underwent physical stress echocardiography were studied. Patients were divided into two groups: with physical stress echocardiography negative (G1) or positive (G2) for myocardial ischemia. The endpoints analyzed were all-cause mortality and major cardiac events, defined as cardiac death and non-fatal acute myocardial infarction. Results: G2 comprised 205 patients (23.7%). During the mean 85.6 ± 15.0-month follow-up, there were 26 deaths, of which six were cardiac deaths, and 25 non-fatal myocardial infarction cases. The independent predictors of mortality were: age, diabetes mellitus, and positive physical stress echocardiography (hazard ratio: 2.69; 95% confidence interval: 1.20 - 6.01; p = 0.016). The independent predictors of major cardiac events were: age, previous coronary artery disease, positive physical stress echocardiography (hazard ratio: 2.75; 95% confidence interval: 1.15 - 6.53; p = 0.022) and absence of a 10% increase in ejection fraction. All-cause mortality and the incidence of major cardiac events were significantly higher in G2 (p < 0. 001 and p = 0.001, respectively). Conclusion: Physical stress echocardiography provides additional prognostic information in patients with exercise test positive for myocardial ischemia.Fundamento: Estudos têm demonstrado a acurácia diagnóstica e o valor prognóstico da ecocardiografia com estresse físico na doença arterial coronária, mas a predição de mortalidade e de eventos cardíacos maiores, em pacientes com teste ergométrico positivo para isquemia miocárdica, é limitada. Objetivo: Avaliar a predição de mortalidade e de eventos cardíacos maiores pela ecocardiografia com estresse físico em pacientes com teste ergométrico positivo para isquemia miocárdica. Métodos: Trata-se de uma coorte retrospectiva em que foram estudados 866 pacientes consecutivos, com teste ergométrico positivo para isquemia miocárdica, submetidos à ecocardiografia com estresse físico. Os pacientes foram divididos em dois grupos: ecocardiografia com estresse físico negativa (G1) ou positiva (G2) para isquemia miocárdica. Os desfechos avaliados foram mortalidade por qualquer causa e eventos cardíacos maiores, definidos como óbito cardíaco e infarto agudo do miocárdio não fatal. Resultados: O G2 constituiu-se de 205 (23,7%) pacientes. Durante o seguimento médio de 85,6 ± 15,0 meses, ocorreram 26 óbitos, sendo seis por causa cardíaca, e 25 casos de infarto agudo do miocárdio não fatais. Os preditores independentes de mortalidade foram idade, diabetes melito e a ecocardiografia com estresse físico + (hazard ratio: 2,69; intervalo de confiança de 95%: 1,20 - 6,01; p = 0,016), com os seguintes eventos cardíacos maiores: idade, doença arterial coronária prévia, ecocardiografia com estresse físico + (hazard ratio: 2,75; intervalo de confiança de 95%: 1,15 - 6,53; p = 0,022) e ausência do incremento de 10% na fração de ejeção. A mortalidade por qualquer causa e os eventos cardíacos maiores foram significativamente superiores no G2 (p < 0, 001 e p = 0,001, respectivamente). Conclusão: A ecocardiografia com estresse físico oferece informações prognósticas adicionais em pacientes com teste ergométrico positivo para isquemia miocárdica.

"Compromising "La Causa"?": The Ford Foundation and Chicano Intellectual Nationalism in the Creation of Chicano History, 1963-1977

ERIC Educational Resources Information Center

MacDonald, Victoria-Maria; Hoffman, Benjamin Polk

2012-01-01

In the early 1970s the first large cohorts of Chicano PhD scholars entered academia, often hired into faculty positions at newly created Chicano departments or centers. The academic identities of the first Chicano PhD scholars were firmly grounded in "Chicanismo," a term which emphasizes ethnic nationalism, political and economic equity, and…

Teaching as a Healing Craft: Decolonizing the Classroom and Creating Spaces of Hopeful Resistance through Chicano-Indigenous Pedagogical Praxis

ERIC Educational Resources Information Center

Villanueva, Silvia Toscano

2013-01-01

This paper builds upon the edict for self-determination in El Plan de Santa Barbara: a Chicano plan for higher education (1969), which calls for "strategic use of education," by placing value on needs of the community (La Causa, p. 9). For me, this passage translates into valuing needs of community-college students entering my classes…

Sunspots and the Newcomb-Benford Law. (Spanish Title: Manchas Solares y la Ley de Newcomb-Benford.) Manchas Solares e a Lei de Newcomb-Benford

NASA Astrophysics Data System (ADS)

Alves, Mauro A.; Lyra, Cássia S.

2008-12-01

The Newcomb-Benford's Law (LNB) of first digits is introduced to high school students in an extracurricular activity through the study of sunspots. The LNB establishes that the first digits of various sets of data describing natural occurrences are not distributed uniformly, but according to a logarithmic distribution of probability. The LNB is counter-intuitive and is a good example of how mathematics applied to the study of natural phenomena can provide surprising and unexpected results serving also as a motivating agent in the study of physical sciences. En este trabajo se describe una actividad extracurricular donde se presenta a los estudiantes la ley de los primeros dígitos de Newcomb-Benford (LNB) con el estudio de manchas solares. La LNB establece que los primeros dígitos de algunos tipos de dados de ocurrencia natural no están distribuidos en manera uniforme, pero sí de acuerdo con una distribución logarítmica de probabilidad. La LNB es contra-intuitiva y es un excelente ejemplo de como las matemáticas aplicadas al estudio de fenómenos naturales pueden sorprender al estudiante, sirviendo también como elemento motivador en la educación de ciencias y de matemáticas. Este trabalho descreve uma atividade extracurricular na qual a lei dos primeiros dígitos de Newcomb-Benford (LNB) é introduzida a estudantes através do estudo de manchas solares. A LNB estabelece que os primeiros dígitos de vários tipos de conjunto de dados de ocorrência natural não são distribuídos de maneira uniforme, mas sim de acordo com uma distribuição logarítmica de probabilidade. A LNB é contra-intuitiva e é um ótimo exemplo de como a matemática aplicada ao estudo de fenômenos naturais pode fornecer resultados surpreendentes e inesperados, servindo também como um agente motivador no ensino de ciências e matemática.

Honduran-U.S. Relations

DTIC Science & Technology

2009-06-08

and congressional approval of 3 “Un 57 Pct de Hondureños Aprueba Gestión Presidente ...DR), by J. F. Hornbeck; and CRS Report R40135, Mérida Initiative for Mexico and Central America: Funding and Policy Issues, by Clare Ribando Seelke...elections loom,” Latin American Economy & Business, May 2009. 17 “Desempleo aumentará a causa de crisis económica,” La Prensa (Honduras), May 22, 2009. 18

PubMed

Wanden-Berghe Lozano, Carmina; Campos Martín, Cristina; Cuerda Compes, Cristina; Gómez Candela, Carmen; Burgos Peláez, Rosa; Moreno Villares, José Manuel; Pereira Cunill, José Luis; Pérez de la Cruz, Antonio; Virgili Casas, Nuria; Martinez Faedo, Ceferino; Álvarez Hernández, Julia; Garde Orbaiz, Carmen; Penacho Lázaro, Mª Ángeles; Sánchez Martos, Eva Ángeles; Sanz Paris, Alejandro; Gonzalo Marín, Montserrat; Zugasti Murillo, Ana; Matía Martín, Pilar; Martín Folgueras, Tomás; Carabaña Pérez, Fátima; Díaz Guardiola, Patricia; Tejera Pérez, Cristina; De Luis Román, Daniel; Luengo Pérez, Luis Miguel; Santacruz Carmona, Nieves; Apezetxea Celaya, Antxón; Ponce González, Miguel Ángel; Urgeles Planella, Juan Ramón; Laborda González, Lucía; Martinez Olmos, Miguel Ángel; Sánchez-Vilar Burdiel, Olga; Joaquín Ortiz, Clara; Martínez Costa, Cecilia; Suárez Llanos, José Pablo; Calleja Fernández, Alicia; Leyes García, Pere; Gil Martinez, Mª Carmen; Mauri Roca, Silvia; García Zafra, Maria Victoria; Carrera Santaliestra, María José; Nadya-Senpe, Grupo

2016-11-29

Objetivo: Comunicar los datos del registro de Nutrición Parenteral Domiciliaria (NPD) del grupo de trabajo NADYA-SENPE del años 2015.Material y métodos: Recopilación de los datos de NPD del registro "on-line" del grupo de Nutrición Artificial Domiciliaria y Ambulatoria (NADYA) desde el 1 de enero de 2015 al 31 de diciembre de 2015.Resultados: Se registraron 236 pacientes, con 243 episodios de NPD procedentes de 40 hospitales. Lo que representa una tasa de 5,08 pacientes/millón de habitantes/ año 2015. La patología más frecuente en los adultos fue "otros" (26,3%) seguido por "oncológico paliativo" (21,6%).  La complicación más frecuente fue la séptica relacionada con el catéter que presentó una tasa de 0,53 infecciones/1000 días de NPD. Finalizaron 64 episodios, la principal causa fue el fallecimiento (43,7%) y el 'paso a la vía oral' (32,8%).Conclusiones: constatamos el aumento de los centros y profesionales colaboradores, dando respuesta a la cantidad progresivamente mayor de pacientes con soporte nutricional parenteral en domicilio. Se mantienen estables las principales indicaciones para el establecimiento de NPD y las causas de finalización del tratamiento.

Zero Calcium Score as a Filter for Further Testing in Patients Admitted to the Coronary Care Unit with Chest Pain.

PubMed

Correia, Luis Cláudio Lemos; Esteves, Fábio P; Carvalhal, Manuela; Souza, Thiago Menezes Barbosa de; Sá, Nicole de; Correia, Vitor Calixto de Almeida; Alexandre, Felipe Kalil Beirão; Lopes, Fernanda; Ferreira, Felipe; Noya-Rabelo, Márcia

2017-06-12

The accuracy of zero coronary calcium score as a filter in patients with chest pain has been demonstrated at the emergency room and outpatient clinics, populations with low prevalence of coronary artery disease (CAD). To test the gatekeeping role of zero calcium score in patients with chest pain admitted to the coronary care unit (CCU), where the pretest probability of CAD is higher than that of other populations. Patients underwent computed tomography for calcium scoring, and obstructive CAD was defined by a minimum 70% stenosis on invasive angiography. In 146 patients studied, the prevalence of CAD was 41%. A zero calcium score was present in 35% of the patients. The sensitivity and specificity of zero calcium score yielded a negative likelihood ratio of 0.16. After logistic regression adjustment for pretest probability, zero calcium score was independently associated with lower odds of CAD (OR = 0.12, 95%CI = 0.04-0.36), increasing the area under the ROC curve of the clinical model from 0.76 to 0.82 (p = 0.006). Zero calcium score provided a net reclassification improvement of 0.20 (p = 0.0018) over the clinical model when using a pretest probability threshold of 10% for discharging without further testing. In patients with pretest probability < 50%, zero calcium score had a negative predictive value of 95% (95%CI = 83%-99%), with a number needed to test of 2.1 for obtaining one additional discharge. Zero calcium score substantially reduces the pretest probability of obstructive CAD in patients admitted to the CCU with acute chest pain. (Arq Bras Cardiol. 2017; [online].ahead print, PP.0-0). A acurácia do escore de cálcio coronário zero como um filtro nos pacientes com dor torácica aguda tem sido demonstrada na sala de emergência e nos ambulatórios, populações com baixa prevalência de doença arterial coronariana (DAC). Testar o papel do escore de cálcio zero como filtro nos pacientes com dor torácica admitidos numa unidade coronariana intensiva (UCI), na qual a probabilidade pré-teste de DAC é maior do que em outras populações. Pacientes foram submetidos a tomografia computadorizada para quantificar o escore de cálcio, DAC obstrutiva foi definida por uma estenose mínima de 70% na cineangiocoronariografia invasiva. Um escore clínico para estimar a probabilidade pré-teste de DAC obstrutiva foi criado em amostra de 370 pacientes, usado para definir subgrupos na definição de valores preditivos negativos do escore zero. Em 146 pacientes estudados, a prevalência de DAC foi 41% e o escore de cálcio zero foi demonstrado em 35% deles. A sensibilidade e a especificidade para escore de cálcio zero resultaram numa razão de verossimilhança negativa de 0,16. Após ajuste com um escore clínico com a regressão logística para a probabilidade pré-teste, o escore de cálcio zero foi preditor independente associado a baixa probabilidade de DAC (OR = 0,12, IC95% = 0,04-0,36), aumentando a área abaixo da curva ROC do modelo clínico de 0,76 para 0,82 (p = 0,006). Considerando a probabilidade de DAC < 10% como ponto de corte para alta precoce, o escore de cálcio aumentou a proporção de pacientes para alta precoce de 8,2% para 25% (NRI = 0,20; p = 0,0018). O escore de cálcio zero apresentou valor preditivo negativo de 90%. Em pacientes com probabilidade pré-teste < 50%, o valor preditivo negativo foi 95% (IC95% = 83%-99%). O escore de cálcio zero reduz substancialmente a probabilidade pré-teste de DAC obstrutiva em pacientes internados em UCI com dor torácica aguda. (Arq Bras Cardiol. 2017; [online].ahead print, PP.0-0).

A Multivariate Model for Prediction of Obstructive Coronary Disease in Patients with Acute Chest Pain: Development and Validation.

PubMed

Correia, Luis Cláudio Lemos; Cerqueira, Maurício; Carvalhal, Manuela; Ferreira, Felipe; Garcia, Guilherme; Silva, André Barcelos da; Sá, Nicole de; Lopes, Fernanda; Barcelos, Ana Clara; Noya-Rabelo, Márcia

2017-04-01

Currently, there is no validated multivariate model to predict probability of obstructive coronary disease in patients with acute chest pain. To develop and validate a multivariate model to predict coronary artery disease (CAD) based on variables assessed at admission to the coronary care unit (CCU) due to acute chest pain. A total of 470 patients were studied, 370 utilized as the derivation sample and the subsequent 100 patients as the validation sample. As the reference standard, angiography was required to rule in CAD (stenosis ≥ 70%), while either angiography or a negative noninvasive test could be used to rule it out. As predictors, 13 baseline variables related to medical history, 14 characteristics of chest discomfort, and eight variables from physical examination or laboratory tests were tested. The prevalence of CAD was 48%. By logistic regression, six variables remained independent predictors of CAD: age, male gender, relief with nitrate, signs of heart failure, positive electrocardiogram, and troponin. The area under the curve (AUC) of this final model was 0.80 (95% confidence interval [95%CI] = 0.75 - 0.84) in the derivation sample and 0.86 (95%CI = 0.79 - 0.93) in the validation sample. Hosmer-Lemeshow's test indicated good calibration in both samples (p = 0.98 and p = 0.23, respectively). Compared with a basic model containing electrocardiogram and troponin, the full model provided an AUC increment of 0.07 in both derivation (p = 0.0002) and validation (p = 0.039) samples. Integrated discrimination improvement was 0.09 in both derivation (p < 0.001) and validation (p < 0.0015) samples. A multivariate model was derived and validated as an accurate tool for estimating the pretest probability of CAD in patients with acute chest pain. Atualmente, não existe um modelo multivariado validado para predizer a probabilidade de doença coronariana obstrutiva em pacientes com dor torácica aguda. Desenvolver e validar um modelo multivariado para predizer doença arterial coronariana (DAC) com base em variáveis avaliadas à admissão na unidade coronariana (UC) devido a dor torácica aguda. Foram estudados um total de 470 pacientes, 370 utilizados como amostra de derivação e os subsequentes 100 pacientes como amostra de validação. Como padrão de referência, a angiografia foi necessária para descartar DAC (estenose ≥ 70%), enquanto a angiografia ou um teste não invasivo negativo foi utilizado para confirmar a doença. Foram testadas como preditoras 13 variáveis basais relacionadas à história médica, 14 características de desconforto torácico e oito variáveis relacionadas ao exame físico ou testes laboratoriais. A prevalência de DAC foi de 48%. Por regressão logística, seis variáveis permaneceram como preditoras independentes de DAC: idade, gênero masculino, alívio com nitrato, sinais de insuficiência cardíaca, e eletrocardiograma e troponina positivos. A área sob a curva (area under the curve, AUC) deste modelo final foi de 0,80 (intervalo de confiança de 95% [IC95%] = 0,75 - 0,84) na amostra de derivação e 0,86 (IC95% = 0,79 - 0,93) na amostra de validação. O teste de Hosmer-Lemeshow indicou uma boa calibração em ambas as amostras (p = 0,98 e p = 0,23, respectivamente). Em comparação com o modelo básico contendo eletrocardiograma e troponina, o modelo completo ofereceu um incremento na AUC de 0,07 tanto na amostra de derivação (p = 0,0002) quanto na de validação (p = 0,039). A melhoria na discriminação integrada foi de 0,09 nas amostras de derivação (p < 0,001) e validação (p < 0,0015). Um modelo multivariado foi derivado e validado como uma ferramenta acurada para estimar a probabilidade pré-teste de DAC em pacientes com dor torácica aguda.

Como Lo Hago Yo: Mielomeningocele En Bolivia

PubMed Central

Dabdoub, Carlos F.; Dabdoub, Carlos B.; Villavicencio, Ramiro; Quevedo, Germán

2014-01-01

Introducción: Las malformaciones del tubo neural (MTN) representan la segunda causa más frecuente de anomalías congénitas, luego de las cardiopatías. En este grupo se destaca el mielomeningocele (MMC) por su mayor incidencia, y por ser la más incapacitante y la más compleja entre todas las demás malformaciones del sistema nervioso c`entral (SNC). En Bolivia, como en muchos países de Sudamérica, los bajos niveles socio-culturales y la debilidad en el sistema sanitario, hacen que su incidencia y su morbilidad, sean mayores que en las naciones más desarrolladas. Material y Métodos: Se realizó un estudio retrospectivo y descriptivo de 70 casos de MMC, atendidos por un equipo multidisciplinario en el Hospital Universitario Japonés (HUJ) de Santa Cruz de la Sierra, entre 2008-2011. De ellos, 60 fueron intervenidos quirúrgicamente. Resultados: Se realizaron controles prenatales sólo en 27 mujeres (38.6%), diagnosticándose una disrafia espinal en apenas dos casos (7.4%). La edad de ingreso del MMC en su mayoría fue después de las 24 horas (65.6%), predominando su localización en la región lumbosacra (64.3%). De ellos, 67.2% eran abiertos, presentando un 32.9% un daño neurológico motor parcial mientras que 47.1% tenían paraplejia por debajo de la lesión. De los 70 casos, tres (4.3%) no fueron intervenidos, por presentar defectos congénitos severos o estado general grave. Las principales complicaciones posoperatorias inmediatas fueron: dehiscencia de sutura y/o infección de la herida (16.6%), fístula de líquido cefalorraquídeo (LCR) (10%) e infección del SNC (11.7%). La mortalidad general y postoperatoria fue de 7.1% y 3.3%, respectivamente. Al mes de vida presentaban hidrocefalia un 80% de los pacientes operados, colocándose una derivación ventriculoperitoneal (DVP) de presión media. De 9 pacientes que tuvieron un acompanamiento de dos o más años, seis presentaron una médula anclada, que fueron intervenidas quirúrgicamente. Conclusión: En esta serie, el diagnóstico prenatal del MMC fue ocasional y la derivación al HUJ de los recién nacidos con esta malformación fue generalmente tardía. No hubo predominio de género y la mayoría de los casos presentaron sus lesiones en la región lumbar y lumbosacra. La mortalidad general y postoperatoria fue similar a la reportada en la literatura. Pocos enfermos realizaron controles posteriores al alta hospitalaria. Igual que otros países de Sudamérica, las falencias en el sistema público de salud y el nivel sociocultural, son factores determinantes para un mal pronóstico en estos niños. Por sus múltiples complicaciones, el MMC requiere de una especial atención gubernamental, sobre todo de carácter preventivo mediante el uso de ácido fólico en mujeres fértiles, como también de un equipo profesional multidisciplinario, a fin de realizar un tratamiento adecuado y oportuno. Al mismo tiempo, trabajos multicéntricos en hospitales de América Latina, ayudarán al mejor manejo de estos pacientes. PMID:24791220

Nursing Diagnosis Based on Signs and Symptoms of Patients With Heart Disease.

PubMed

da Costa, Cíntia; da Costa Linch, Graciele Fernanda; Nogueira de Souza, Emiliane

2016-10-01

The aim was to identify the main signs and symptoms of cardiac patients hospitalized in a unit of intensive cardiology care in order to infer the main nursing diagnoses (NDs). We performed a cross-sectional study; the sample consisted of 77 randomly selected records. Those records included only patients hospitalized for cardiovascular causes and with electronic chart available. Signs and symptoms identified at admission were psychic (40.3%), compressive dressing on arterial puncture site (33.8%), chest pain (29.9%), tachycardia (22.1%), and hemodynamic instability (20.8%). According to the data collected, we were able to infer that acute pain, excess of fluid volume, decreased cardiac output, spontaneous ventilation impaired, anxiety and impaired skin integrity are priority for the NDs in the studied population. OBJETIVO: identificar os principais sinais e sintomas de pacientes cardíacos internados em uma unidade de cuidados intensivos de cardiologia, visando inferir os diagnósticos de enfermagem prioritários. MÉTODO: Estudo transversal; a amostra foi composta por 77 registros selecionados aleatoriamente. Incluíram-se apenas pacientes internados por causa cardiovascular e com registro eletrônico disponível. Os sinais e sintomas identificados na admissão foram psíquicos (40,3%), curativo compressivo em sítio de punção arterial (33,8%), dor torácica (29,9%), taquicardia (22,1%) e instabilidade hemodinâmica (20,8%). CONCLUSÕES E IMPLICAÇÕES PARA A PRÁTICA: De acordo com os dados levantados foram inferidos Dor Aguda, Volume de Líquidos Excessivo, Débito Cardíaco Diminuído, Ventilação Espontânea Prejudicada, Ansiedade e Integridade da Pele Prejudicada como diagnósticos de enfermagem prioritários para a população estudada. © 2016 NANDA International, Inc.

Tiempo para un cambio

NASA Astrophysics Data System (ADS)

Woltjer, L.

1987-06-01

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

Victory, Stalemate and Defeat During the Spanish Caribbean Insurgencies of 1868-1878

DTIC Science & Technology

2015-05-01

Press of America, Inc., 2009. Bell, Ian. The Dominican Republic. Boulder: Westview Press, 1981. de Navascues y Aisa , Nicasio. "Parte de la Alcaldia de...2006. Jimenez de Wagenheim, Olga. El grito de Lares sus causas y sus hombres. 4th Edition . Rio Piedras, Puerto Rico: Ediciones Huracan, Inc., 1999...1987. Marti, Jose. Our America: Writing on Latin America and the Struggle for Cuban Independence. Edited by Philip S. Foner. Translated by Elinor

The United States and Brazil: Opening a New Dialogue,

DTIC Science & Technology

1984-01-01

Alexandre de Barros, Ŕ Coroamento De Uma Politica Extema Criativa [The Coronation of a Creative External Policy]," Jornal Do Brasil, 3 October 1982...August 1982, p. 7. 19. Ŕ Avango Da Estatizagho: A Causa Principal Das Mazel as Da Economia (The Advance of Estatizatlon: The Principal Cause of the...Wounds of the Economy]," Visdo-Quemn t Quem Na Economia Brasiilra, August 1962, pp. 6-13. 20. Cecilla Costa, "A Mfigica Que 0 Gov6rno Faz Para Cobrir Seu

Factors associated with mortality in patients undergoing coronary artery bypass grafting.

PubMed

Koerich, Cintia; Lanzoni, Gabriela Marcellino de Melo; Erdmann, Alacoque Lorenzini

2016-08-08

to investigate the factors associated with mortality in patients undergoing coronary artery bypass grafting in a cardiovascular referral hospital in Santa Catarina. quantitative, exploratory, descriptive and retrospective study. The medical records of 1447 patients, from 2005 to 2013, were analyzed for statistically related variables, these being: profile, hospitalization diagnosis, risk factors for coronary artery disease, complications recorded during the hospitalization, length of hospitalization and cause of death. the mortality rate was 5.3% during the study period. Death was more common in females and those of black skin color, with a mean age of 65 years. Acute myocardial infarction was the most common hospitalization diagnosis. The majority of the complications recorded during hospitalization were characterized by changes in the cardiovascular system, with longer hospitalization periods being directly related to death from septic shock. the data provide subsidies for nursing work with preventive measures and early detection of complications associated with coronary artery bypass grafting. This reinforces the importance of using the data as quality indicators, aiming to guarantee care guided by reliable information to guide managers in planning patient care and high complexity health services. conhecer os fatores associados à mortalidade de pacientes submetidos à cirurgia de revascularização do miocárdio em hospital referência cardiovascular em Santa Catarina. estudo quantitativo, exploratório, descritivo e retrospectivo. Foram analisados os prontuários de 1447 pacientes, entre 2005 e 2013, e as variáveis relacionadas estatisticamente, sendo estas: perfil, diagnóstico da internação, fatores de risco para doença arterial coronariana, intercorrências registradas na internação, tempo de internação e causa do óbito. a taxa de mortalidade foi de 5,3% no período do estudo. Os óbitos foram mais frequentes em negros, do sexo feminino e média de idade de 65 anos. O infarto agudo do miocárdio foi o diagnóstico de internação que apresentou maior representatividade. A maioria das intercorrências registradas durante a internação caracterizou-se por alterações do sistema cardiovascular e o maior tempo de internação teve relação direta com óbito por choque séptico. os dados fornecem subsídios para a enfermagem atuar com medidas preventivas e identificação precoce de intercorrências associadas à cirurgia de revascularização do miocárdio. Reforça-se a importância da utilização dos dados como indicadores de qualidade objetivando garantir um cuidado pautado em informações confiáveis que orientem gestores no planejamento da assistência ao paciente e dos serviços de saúde de alta complexidade. conocer los factores asociados a la mortalidad de pacientes sometidos a cirugía de revascularización del miocardio en un hospital de referencia cardiovascular en el estado de Santa Catarina. estudio cuantitativo, exploratorio, descriptivo y retrospectivo. Fueron analizados las fichas médicas de 1.447 pacientes, entre 2005 y 2013; las variables relacionadas estadísticamente fueron: perfil, diagnóstico de la internación, factores de riesgo para enfermedad arterial coronariana, complicaciones registradas en la internación, tiempo de internación y causa de la muerte. la tasa de mortalidad fue de 5,3%, en el período del estudio. Las muertes fueron más frecuentes en negros, sexo femenino y promedio de edad de 65 años. El infarto agudo del miocardio fue el diagnóstico de internación que presentó mayor representatividad. La mayoría de las complicaciones registradas durante la internación se caracterizó por alteraciones del sistema cardiovascular; el mayor tiempo de internación tuvo relación directa con muerte por choque séptico. los datos suministran informaciones para que la enfermería pueda actuar con medidas preventivas e identificar precozmente complicaciones asociadas a la cirugía de revascularización del miocardio. Se refuerza la importancia de la utilización de datos como indicadores de calidad, objetivando garantizar un cuidado guiado por informaciones confiables que orienten a los administradores en la planificación de la asistencia al paciente y en los servicios de salud de alta complejidad.

Modelo analítico del efecto de PRS sobre satélites GPS

NASA Astrophysics Data System (ADS)

Meza, A.; Brunini, C.; Usandivaras, J. C.

El sistema GPS (Global Position System) es, hoy en día, la herramienta de navegación y posicionamiento más potente y lo será sin duda en la próxima década. Gran parte de su valiosa utilidad se debe a la alta precisión que permite lograr y ésta, a su vez, depende, entre otras causas, de la precisión con que se conocen las órbitas de los satélites. La presión de radiación solar (PRS) fija el límite de la precisión con que pueden calcularse en la actualidad las efemérides satelitarias. El objetivo de este trabajo es proponer una mejor resolución de este fenómeno. El modelo analítico aquí presentado, se basa en el análisis del comportamiento de los residuos de un ajuste por mínimos cuadrados en el que se utiliza el modelo de PRS propuesto por Beutler. El mismo consiste en un modelo determinista del fenómeno con dos parámetros libres. Los resultados obtenidos ponen de manifiesto que, aún después de aplicar dichos parámetros, prevalecen en los residuos efectos semidiurnos en las componentes radial,tangencial y normal. Estos resultados obtenidos se comparan con los de un trabajo desarrollado por el Instituto de Berne (Beutler et al., 1994), en el que se utilizaron como pseudo-observaciones las órbitas precisas del IGS (CODE). El intervalo de integración escogido por este centro fueron las semanas 680 y 681. En resumen se tienen arcos de 14 días para todos los satélites, donde las efemérides precisas de los mismos para los 14 días fueron utilizados como pseudo-observaciones. El modelo de fuerza que empleó dicho centro fue básicamente el tradicional en lo que respecta al modelo de las fuerzas gravitacionales, y para la PRS utilizo el modelo standard de Beutler. Los parámetros de este modelo junto con las 6 condiciones iniciales (posición y velocidad) fueron ajustados por el método general de mínimos cuadrados. Los residuos en la componente radial, tangencial y normal, para los satélites con un buen comportamiento, presentan una componente semidiurna. El modelo analítico planteado en este trabajo, predice el comportamiento de los residuos que se observan en las publicaciones más recientes. Esto abre el camino para plantear una estimación distinta de las incógnitas del problema, basado en el método de colocación por mínimos cuadrados. Ello requiere modelar estadísticamente la señal debida a las componentes de la PRS que no son tomadas en cuenta en el modelo determinista.

Effects of H sub 2 S addition on the performance of fresh vs. used CoMo catalysts

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

Rankel, L.A.

1991-01-01

When a Co/Mo catalyst is used for processing vanadium-containing heavy oils, vanadium deposits on the catalyst. As the amount of vanadium on the CoMo catalyst increases, the catalytic effects of CoMo decline and the presence of vanadium starts to influence the hydroprocessing products. Model feeds have been used to explore the changes in the catalytic activity of CoMo, aged CoMo, and VS{sub x} on alumina. Desulfurization, denitrogenation, deoxygenation, aromatics hydrogenation, and metals removal were monitored. This paper reports that, upon the addition of hydrogen sulfide to hydrogen, improvements in the catalysts for aromatics hydrogenation, denitrogenation and metals removal were observed.

Física e Arte nas Estações do Ano

NASA Astrophysics Data System (ADS)

Pessôa Queiroz, Glória; da Conceição Barbosa Lima, Maria; Navarro Vasconcellos das Mercês, Maria

2004-12-01

The paper deals with the subject of the Four Seasons, exploring elements of Science and the Art in order to motivate students or public of museums of science and technology to understand it from their current cultural experiences and of old times. Physics joins to Astronomy to explain the phenomenon, while the use of Music and Painting make possible the immersion in the subject in way to many trips to the imagination capable to awake emotions.A proposal didactic is presented and justified for some consensus of the research in the area of teaching-learning of science, since that related to the persistent alternative conceptions concerning the causes of the changes observed at the different times of the year until the qualitative modelling of phenomena that appeals three-dimensional pedagogical models. Such proposal was developed in the activity named " Hiper interesting Talk: The Four Seasons, Science and Art" in the first Sunday of August/2003 in the Museum of Astronomy, MAST. O artigo trata do tema das Estações do Ano, explorando elementos da Ciência e da Arte como forma de motivar estudantes ou público de museus de ciência e tecnologia a compreendê-lo a partir de vivências culturais atuais e de outras épocas. A Física se junta à Astronomia para explicar o fenômeno, enquanto a Música e a Pintura possibilitam a imersão no tema em meio a muitas viagens à imaginação capazes de despertar emoções.Uma proposta didática é apresentada e justificada por consensos das muitas pesquisas na área de ensino-aprendizagem de ciências, desde os que se referem às persistentes concepções alternativas acerca das causas das mudanças observadas nas diferentes épocas do ano até à modelagem qualitativa de fenômenos que recorre a modelos pedagógicos tridimensionais. Tal proposta foi desenvolvida na atividade "Bate papo Hiperinteressante: As Quatro Estações, Ciência e Arte" realizada no primeiro domingo do mês de agosto de 2003 no Museu de Astronomia.

Cholesterol and prevention of atherosclerotic events: limits of a new frontier.

PubMed

Macedo, Luís Eduardo Teixeira de; E, Faerstein

2017-01-12

Control of atherosclerotic cardiovascular disease - a highly prevalent condition and one of the main causes of mortality in Brazil and worldwide - is a recurrent subject of great interest for public health. Recently, three new guidelines on dyslipidemia and atherosclerosis prevention have been published. The close release of these important publications is a good opportunity for comparison: the Brazilian model has greater sensitivity, the English model does not work with risk stratification, and the American model may be overestimating the risk. This will allow reflection on current progress and identification of controversial aspects which still require further research and debate. It is also an opportunity to discuss issues related to early diagnosis and its efficiency as a preventive strategy for atherosclerotic disease: the transformation of risk into disease, the gradual reduction of cut-off points, the limitations of the screening strategy, and the problem of overdiagnosis. RESUMO O controle da doença cardiovascular aterosclerótica - morbidade de alta prevalência e uma das principais causas de mortalidade no Brasil e no mundo - continua sendo tema de grande interesse para a Saúde Pública. Recentemente, três novas diretrizes sobre dislipidemia e prevenção da aterosclerose foram divulgadas. A convergência no tempo dessas importantes publicações constitui boa oportunidade para sua comparação: o modelo brasileiro tem maior sensibilidade, o inglês não trabalha com risco estratificado e o norte-americano parece estar superestimando o risco.Isso permitirá reflexões acerca dos avanços que já foram alcançados e identificação de aspectos ainda controversos, que seguem exigindo novas pesquisas e debates. É também uma oportunidade para discutir questões relacionadas ao diagnóstico precoce e sua eficiência como estratégia preventiva da doença aterosclerótica: as transformações do risco em doença, a diminuição progressiva de pontos de corte, as insuficiências da estratégia de rastreamento e o problema do sobrediagnóstico.

Descompresión microvascular en espasmo hemifacial: Reporte de 13 casos y revisión de la literatura

PubMed Central

Campero, Alvaro; Herreros, Isabel Cuervo-Arango; Barrenechea, Ignacio; Andjel, Germán; Ajler, Pablo; Rhoton, Albert

2016-01-01

Objetivo: El propósito del presente trabajo es presentar los resultados de 13 pacientes con diagnóstico de espasmo hemifacial (EHF), en los cuales se realizó una descompresión microvascular (DMV). Material y Método: Desde Junio de 2005 a Mayo de 2014, 13 pacientes con diagnóstico de EHF fueron intervenidos quirúrgicamente, realizando una DMV. Se evaluó: edad, sexo, tiempo de evolución de la sintomatología, hallazgos intraoperatorios y resultados postoperatorios. Resultados: De los 13 pacientes intervenidos, 7 fueron mujeres y 6 varones. La media de edad fue de 53 años. El tiempo medio entre el inicio de la sintomatología y la intervención quirúrgica osciló entre 3 y 9 años. En todos los casos el EHF era típico, uno de ellos con neuralgia trigeminal concomitante, observándose en todos compresión neurovascular intraoperatoria. Por orden decreciente de frecuencia la causa de la compresión fue arteria cerebelosa anteroinferior, arteria cerebelosa posteroinferior, arteria dolicomega basilar y arteria dolicomega vertebral. El seguimiento postoperatorio fue en promedio de 24 meses. El 62% presentó desaparición postquirúrgica inmediata de la sintomatología preoperatoria, el 30% desaparición tras un período de 3 semanas a 2 meses (8% con mejoría parcial), y en el 8% no hubo mejoría. En cuanto a las complicaciones postoperatorias: 3 pacientes presentaron paresia facial II-III en la escala de House-Brackman (se recuperaron en un período de 6 meses), y 1 paciente presentó fístula de líquido cefalorraquídeo. Ninguno de los pacientes de la serie presentaron hipoacusia transitorio o permanente. Conclusión: La DMV como tratamiento del EHF es un procedimiento efectivo y seguro, que permite la resolución completa de la patología en la mayoría de los casos. PMID:27127708

Descripción del coronógrafo a ser instalado en Argentina (MICA)

NASA Astrophysics Data System (ADS)

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

El ``Coronógrafo de espejo para Argentina'' es un telescopio solar terrestre a ser colocado en el Observatorio Astronómico Félix Aguilar (El Leoncito), antes de finalizar 1996, como parte de un programa de ciencia bilateral entre Alemania y Argentina. Eclipses fotográficos de alta resolución han revelado que la corona solar es altamente estructurada y variable. De hecho, está contínuamente deformada y moldeada por los movimientos convectivos de los extremos de los arcos magnéticos en la fotosfera, estando, en muchas oportunidades, afectada por explosivas liberaciones de energía. MICA, en conjunción con otros telescopios solares espaciales y terrestres, tratará de contribuir al entendimiento de cuestiones fundamentales de la física solar. Entre ellas: cómo la corona está siendo calentada, dónde y cómo el viento solar es acelerado, qué causa los transitorios coronales, etc. Para ello investigará la distribución de los parámetros del plasma y su evolución con el tiempo, la estructura espacial de la corona en fina y gran escala, procesos que ocurren en los transitorios coronales y factores que los disparan, etc. Para responder a estas cuestiones MICA observará la atmósfera solar por sobre el limbo entre 1.1 y 2 radios solares aproximadamente, usando un nuevo tipo de sistema coronográfico que permite suprimir el brillo del disco solar suficientemente bien, tomando las imágenes con una cámara CCD de 1024x1024 pixels, codificada en 12 bits, pudiendo el mismo ser operado en forma remota. En la presente exposición describiremos las características del instrumento, cómo será controlado y qué esperamos observar basados en las imágenes obtenidas por los telescopios de similares características LASCO C1 a bordo del SOHO y PICO (ubicado en el Observatorio de Pic du Midi, Francia).

Interview with Irving W Wainer.

PubMed

Wainer, Irving W

2013-08-01

Irving W Wainer, Senior Investigator in the Intramural Research Program at the National Institute on Aging/NIH received his PhD degree in chemistry from Cornell University and did postdoctoral doctoral studies in molecular biology (University of Oregon) and clinical pharmacology (Thomas Jefferson Medical School). He worked for the US FDA and held positions at St Jude's Children's Research Hospital, at McGill University as Professor in the Department of Oncology, and as a Professor of Pharmacology at Georgetown University. Wainer has published over 350 scientific papers, 10 books, 25 book chapters and holds 11 patents. His awards include: 'A.J.P. Martin Medal' presented by the Chromatographic Society; Doctor HonorisCausa awarded by the Medical University of Gdansk (Gdansk, Poland, 2006), Doctor HonorisCausa awarded by the Department of Medicine, University of Liege (Liege, Belgium, 2012), and the 2013 Eastern Analytical Symposium Award for Outstanding Contributions to the Fields of Analytical Chemistry. Wainer's research includes the development of new therapeutic agents for the treatment of congestive heart failure, cancer, pain and depression, many of which are in the later stages of drug development. His laboratory has also continued the development of cellular membrane affinity chromatography technology, and recent work includes the development of columns containing immobilized forms of the breast cancer resistance protein found in cellular and nuclear membranes and mitochondrial membrane columns. Wainer's laboratory has also continued its study of the effect of disease progression and aging on drug metabolism in critically ill and terminal patients. Interview was conducted by Lisa Parks, Assistant Commissioning Editor of Bioanalysis.

TUBERCULOSIS COMO ENFERMEDAD OCUPACIONAL

PubMed Central

Mendoza-Ticona, Alberto

2014-01-01

Existe evidencia suficiente para declarar a la tuberculosis como enfermedad ocupacional en diversos profesionales especialmente entre los trabajadores de salud. En el Perú están normados y reglamentados los derechos laborales inherentes a la tuberculosis como enfermedad ocupacional, como la cobertura por discapacidad temporal o permanente. Sin embargo, estos derechos aún no han sido suficientemente socializados. En este trabajo se presenta información sobre el riesgo de adquirir tuberculosis en el lugar de trabajo, se revisan las evidencias para declarar a la tuberculosis como enfermedad ocupacional en trabajadores de salud y se presenta la legislación peruana vigente al respecto. PMID:22858771

Conocimiento de Energía: Principios Esenciales y Conceptos Fundamentales para la Educación de Energía (in Spanish)

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

None

This is the Spanish version of our Energy Literacy guidebook. Esta guía presenta conceptos de energía que, cuando se entienden y se aplican, ayudan a individuos y a comunidades a tomar decisiones sobre la energía con conocimiento de causa. No es un currículo sino que ofrece un marco sobre el cual puede basarse un plan de estudios. La guía se dirige a cualquier persona que participe en la educación de energía.

Trends in corrected lung cancer mortality rates in Brazil and regions.

PubMed

Malta, Deborah Carvalho; Abreu, Daisy Maria Xavier de; Moura, Lenildo de; Lana, Gustavo C; Azevedo, Gulnar; França, Elisabeth

2016-06-27

To describe the trend in cancer mortality rates in Brazil and regions before and after correction for underreporting of deaths and redistribution of ill-defined and nonspecific causes. The study used data of deaths from lung cancer among the population aged from 30 to 69 years, notified to the Mortality Information System between 1996 and 2011, corrected for underreporting of deaths, non-registered sex and age , and causes with ill-defined or garbage codes according to sex, age, and region. Standardized rates were calculated by age for raw and corrected data. An analysis of time trend in lung cancer mortality was carried out using the regression model with autoregressive errors. Lung cancer in Brazil presented higher rates among men compared to women, and the South region showed the highest death risk in 1996 and 2011. Mortality showed a trend of reduction for males and increase for women. Lung cancer in Brazil presented different distribution patterns according to sex, with higher rates among men and a reduction in the mortality trend for men and increase for women. Descrever a tendência da mortalidade por câncer de pulmão no Brasil e regiões, antes e após as correções por sub-registro de óbitos, redistribuição de causas mal definidas e causas inespecíficas. Foram utilizados dados de óbitos por câncer de pulmão da população de 30 a 69 anos, notificados ao Sistema de Informação sobre Mortalidade, entre 1996 e 2011, corrigidos para sub-registro de óbitos, declaração de sexo e idade ignorados e causas com códigos mal definidos e inespecíficos segundo sexo, idade e região. Foram calculadas taxas padronizadas por idade para dados brutos e corrigidos. Realizou-se análise da tendência temporal da mortalidade por câncer de pulmão por meio do modelo de regressão com erros autorregressivos. O câncer de pulmão no Brasil apresentou taxas mais elevadas em homens que em mulheres e a região Sul foi a que apresentou maior risco de morte em 1996 e 2011. A mortalidade tendeu a reduzir para o sexo masculino e a aumentar para o sexo feminino. O câncer de pulmão no Brasil apresenta padrão de distribuição diferente segundo sexo, com taxas mais elevadas em homens e com redução da tendência de mortalidade para o sexo masculino e aumento das taxas para o sexo feminino.

A causa das estações do ano: modelos mentais

NASA Astrophysics Data System (ADS)

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

2003-08-01

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

The Variation of Catalyst and Carrier Gas on Anisole Deoxygenation Reaction

NASA Astrophysics Data System (ADS)

Ariyani, D.; Dwi Nugrahaningtyas, Khoirina; Heraldy, E.

2018-03-01

This research aims to determine the best catalyst and carrier gas in anisole deoxygenation reaction. The reaction was carried out over a flow system with a variation of catalyst CoMo A (CoMo/USY reduction), CoMo B (CoMo/USY oxidation-reduction), and CoMo C (CoMo/ZAA oxidation-reduction). In addition, variation of carrier gas nitrogen and hydrogen was investigated. The result was analyzed using Gas Chromatography-Mass Spectroscopy (GC-MS). The deoxygenation anisole result showed that CoMo A catalyst with hydrogen as the carrier gas has the highest total product yield (50.72 %), intermediate product yield (38.49 % in phenol and 6.99 % in benzaldehyde), and deoxygenation yield (5.24 %). The CoMo C catalyst exhibited the most selective deoxygenation product. The nitrogen carrier gas with the CoMo C catalyst has the best selectivity of benzene product (93.92 %).

Calcium supplementation for reducing weight in people with obesity; an overview of systematic reviews

PubMed

Aguilera Eguía, Raúl; Jorquera Pino, Paula Jessica; Salgado, Claudia Jaqueline; Flores, Cherie

2016-09-20

Introducción: actualmente la obesidad es considerada un problema de salud pública, y en la mayor parte de los países ha evolucionado como una pandemia, presentando un incremento en su prevalencia y severidad.Objetivo:resumir las revisiones sistemáticas Cochrane y no Cochrane que evalúen el efecto de la suplementación de calcio en la disminución de grasa corporal en personas obesas.Materiales y métodos: se realizó una búsqueda en la base de datos Medline (1980-septiembre 2015), Metabuscador TripDatabase y Epistemonikos (hasta septiembre 2015), Cochrane BVS (hasta septiembre 2015), se buscó de forma manual en revistas relacionadas con el tema de interés, en actas de congresos, se realizó seguimiento de referencias relevantes y se contactó con expertos en el área.Resultados: la búsqueda preliminar arrojó un total de 7.163 artículos potencialmente elegibles, según los criterios de elegibilidad incluimos 2 revisiones sistemáticas de estudios clínicos aleatorizados.Conclusión: el suplemento de calcio al parecer sería efectivo en la disminución de grasa corporal, DM -0,51 (-1,27, 0,25); (p = 0,19), presentando "baja evidencia" según la metodología GRADE, esto quiere decir que "es muy probable que investigaciones adicionales tengan un impacto importante en la confianza de la estimación del efecto y es probable que cambie".

Evolución en el tiempo de las relaciones Masa-Luminosidad y Corrección Bolométrica y Temperatura Efectiva contra Índice de Color

NASA Astrophysics Data System (ADS)

Miloni, L. A.; Camperi, J. A.

Analizamos la evolución que en los últimos 70 años han tenido las relaciones M-L, BC vs CI y Teff vs CI. Se discuten las causas de esa evolución, se trata de incorporar los valores más modernos disponibles discutiendo su calidad y se deducen las relaciones que actualmente deberían ser las más confiables. Destacamos los puntos en los que estas relaciones continúan estando pobremente definidas y sería deseable mejorar en el futuro próximo.

The English as a Foreign Language/Lingua Franca Debate: Sensitising Teachers of English as a Foreign Language towards Teaching English as a Lingua Franca (El debate del inglés como lengua extranjera o como lengua franca: sensibilización de docentes de inglés como lengua extranjera hacia la enseñanza del inglés como lengua franca)

ERIC Educational Resources Information Center

Mansfield, Gillian; Poppi, Franca

2012-01-01

The function of English as a lingua franca for communication needs rethinking in the teaching of English as a foreign language classroom as a consequence of globalisation. The present contribution is an empirical study carried out in an Italian university environment which aims to show how teachers should take on board awareness raising activities…

High-energy asymmetric supercapacitors based on free-standing hierarchical Co-Mo-S nanosheets with enhanced cycling stability.

PubMed

Balamurugan, Jayaraman; Li, Chao; Peera, Shaik Gouse; Kim, Nam Hoon; Lee, Joong Hee

2017-09-21

Layered transition metal sulfides (TMS) are emerging as advanced materials for energy storage and conversion applications. In this work, we report a facile and cost-effective anion exchange technique to fabricate a layered, multifaceted, free standing, ultra-thin ternary cobalt molybdenum sulfide nanosheet (Co-Mo-S NS) architecture grown on a 3D porous Ni foam substrate. The unique Co-Mo layered double hydroxides are first synthesized as precursors and consequently transformed into ultra-thin Co-Mo-S NS. When employed as an electrode for supercapacitors, the Co-Mo-S NS delivered an ultra-high specific capacitance of 2343 F g -1 at a current density of 1 mA cm -2 with tremendous rate capability and extraordinary cycling performance (96.6% capacitance retention after 20 000 cycles). Furthermore, assembled Co-Mo-S/nitrogen doped graphene nanosheets (NGNS) in an asymmetric supercapacitor (ASC) device delivered an excellent energy density of 89.6 Wh kg -1 , an amazing power density of 20.07 kW kg -1 , and superior cycling performance (86.8% capacitance retention after 50 000 cycles). Such exceptional electrochemical performance of Co-Mo-S NS is ascribed to the good electrical contact with the 3D Ni foam, ultra-high contact area with the electrolyte, and enhanced architectural softening during the charging/discharging process. It is expected that the fabricated, unique, ultra-thin Co-Mo-S NS have great potential for future energy storage devices.

A sup 57 Co Moessbauer emission spectrometric study of some supported CoMo hydrodesulfurization catalysts

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

Veen, J.A.R. van; Hendriks, P.A.J.M.; Beens, H.

1992-01-01

A suite of 11 CoMo/Al{sub 2}O{sub 4} (and one CoMo/SiO{sub 2}) catalysts has been prepared employing four preparation routes, viz. one sequential-impregnation route and three different coimpregnation routes. Speciation of the Co present in the oxidic precursors (octahedral vs tetrahedral Co) and in the activated, sulfided catalysts (CoMoS, Co{sub 9}S{sub 8}, and unsulfided Co) was effected with the aid of {sup 57}Co Moessbauer emission spectroscopy (MES). A linear relation between the thiophene-hydrodesulfurization (HDS) activity and wt% Co-in-CoMoS was observed for each preparation route, but no unique correlation was found to exist. This was traced to the fact that the preparationmore » routes differ in the amount of CoMoS I and CoMoS II they produce in the activated catalyst. Although these two phases differ in specific activity, CoMoS II being twice as active in thiophene HDS as CoMoS I, they cannot be distinguished on the basis of their Moessbauer parameters. It appears that octahedral Co is easier to sulfide than tetrahedral Co, but a substantial fraction of the latter is also found to be capable of entering CoMoS upon sulfidation. The reduced effectiveness of high-loading catalysts is traced to their being prone to CoMoO{sub 4} formation in the calcination step. A rationalization of this behavior is offered.« less

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.

[Levels of trace elements in the fruits and vegetables from the so-called Land of fires in Campania Region (Southern Italy)].

PubMed

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.

[The "diagnosis" in the light of Charles S. Peirce, Sherlock Holmes, Sigmund Freud and modern neurobiology].

PubMed

Adler, R H

2006-05-10

A diagnostic hypothesis is a causa ficta. It is an assumption, suitable to explain phenomena, which are not yet proven to be the only and valid explanation of the observed. One of Wilhelm Hauff's faitales illustrates how a hypothesis is generated. It is based on the interpretation of signs. Signs are of an ikonic, an indexical or a symbolic nature. According to S. Peirce, a hypothesis is created by abduction, to Conan Doyle's Sherlock Holmes by immersion into thoughts, and to S. Freud by free floating attention. The three procedures are alike. Neurobiological structures and functions, which correspond to these processes, are described; especially the emotional-implicite memory. The technique of hypothesis-generation is meaningful to clinical medicine.

CoMoS2/rGO/C3N4 ternary heterojunctions catalysts with high photocatalytic activity and stability for hydrogen evolution under visible light irradiation

NASA Astrophysics Data System (ADS)

Xu, Xuejun; Si, Zhichun; Liu, Liping; Wang, Zehao; Chen, Ze; Ran, Rui; He, Yonghong; Weng, Duan

2018-03-01

Noble metal free MoS2/g-C3N4 catalyst has attracted intense attentions for visible light photocatalytic hydrogen evolution as a result of its earth abundance, low cost and unique heterojunctions stacked with two dimensional sheets. However, the low charge separation efficiency resulted from the poor conductivity of g-C3N4 and MoS2, and lack of abundant active sites from coordinative unsaturated atoms in MoS2, restricts the photocatalytic hydrogen evolution activity and stability enhancement of MoS2/C3N4 composite catalysts. Herein, CoMoS2/rGO/g-C3N4 catalysts with ternary heterojunctions are prepared by facile solvothermal method, which exhibit high visible light photocatalytic activity and stability for hydrogen evolution. The optimal hydrogen evolution rate of CoMoS2/rGO/g-C3N4 catalysts is 684 μmol g-1 h-1 when the content of CoMoS2 is 2% and the content of rGO is 0.5%. The stability of CoMoS2/rGO/C3N4 catalysts just decrease about 3% after 4 cycling runs for 16 h. The good catalytic performances of catalysts are attributed to the synergistic effect among the g-C3N4 nanosheets, rGO nanosheets and CoMoS2 nanosheets. The high conductivity of rGO nanosheets enhances the electron-hole separation and charge transfer, and Co doping increases the active sites for hydrogen evolution due to the increase of unsaturated atoms in CoMoS2 nanosheets.

COMO: a numerical model for predicting furnace performance in axisymmetric geometries. Volume 1. Technical summary. Final report

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

Fiveland, W.A.; Oberjohn, W.J.; Cornelius, D.K.

1985-12-01

This report summarizes the work conducted during a 30-month contract with the United States Department of Energy (DOE) Pittsburgh Energy Technology Center (PETC). The general objective is to develop and verify a computer code capable of modeling the major aspects of pulverized coal combustion. Achieving this objective will lead to design methods applicable to industrial and utility furnaces. The combustion model (COMO) is based mainly on an existing Babcock and Wilcox (B and W) computer program. The model consists of a number of relatively independent modules that represent the major processes involved in pulverized coal combustion: flow, heterogeneous and homogeneousmore » chemical reaction, and heat transfer. As models are improved or as new ones are developed, this modular structure allows portions of the COMO model to be updated with minimal impact on the remainder of the program. The report consists of two volumes. This volume (Volume 1) contains a technical summary of the COMO model, results of predictions for gas phase combustion, pulverized coal combustion, and a detailed description of the COMO model. Volume 2 is the Users Guide for COMO and contains detailed instructions for preparing the input data and a description of the program output. Several example cases have been included to aid the user in usage of the computer program for pulverized coal applications. 66 refs., 41 figs., 21 tabs.« less

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

NASA Astrophysics Data System (ADS)

Iachel, Gustavo

2011-12-01

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

Múltiples estados de desorden en el etanol sólido

NASA Astrophysics Data System (ADS)

Fernández-Perea, R.

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

PubMed

Silva, Cristiane Gonçalves da; Santos, Alessandro Oliveira; Licciardi, Daniele Carli; Paiva, Vera; Parker, Richard

2008-01-01

Esse artigo descreve como jovens religiosos e autoridades religiosas de sua comunidade compreendem a sexualidade, considerando suas experiências pessoais e como membros de comunidades religiosas. A análise pretende contribuir para que políticas públicas dedicadas à promoção da saúde sexual da juventude considerem a religiosidade, no contexto de um estado laico e da promoção do direito à prevenção. Foram realizadas 26 entrevistas abertas e semidirigidas em diferentes comunidades da região metropolitana da cidade de São Paulo (comunidades católicas, da umbanda, do candomblé e de diferentes denominações evangélicas) sobre iniciação sexual, casamento, gravidez, contracepção e prevenção das DST/Aids, homossexualidade, aborto e direitos humanos. Observou-se como jovens e autoridades religiosas convivem com a tensão entre tradição e modernidade e os distintos discursos sobre a sexualidade. Como sujeitos religiosos (do discurso religioso) e sujeitos sexuais (de discursos sobre sexualidade), devem ser incorporados pelos programas como sujeitos de direito nos termos de sua religiosidade.

Sexual selection on multivariate phenotypes in Anastrepha Fraterculus (Diptera: Tephritidae) from Argentina

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

Sciurano, R.; Rodriguero, M.; Gomez Cendra, P.

Despite the interest in applying environmentally friendly control methods such as sterile insect technique (SIT) against Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), information about its biology, taxonomy, and behavior is still insufficient. To increase this information, the present study aims to evaluate the performance of wild flies under field cage conditions through the study of sexual competitiveness among males (sexual selection). A wild population from Horco Molle, Tucuman, Argentina was sampled. Mature virgin males and females were released into outdoor field cages to compete for mating. Morphometric analyses were applied to determine the relationship between the multivariate phenotype and copulatory success.more » Successful and unsuccessful males were measured for 8 traits: head width (HW), face width (FW), eye length (EL), thorax length (THL), wing length (WL), wing width (WW), femur length (FL), and tibia length (TIL). Combinations of different multivariate statistical methods and graphical analyses were used to evaluate sexual selection on male phenotype. The results indicated that wing width and thorax length would be the most probable targets of sexual selection. They describe a non-linear association between expected fitness and each of these 2 traits. This non-linear relation suggests that observed selection could maintain the diversity related to body size. (author) [Spanish] A pesar del interes por la aplicacion de metodos de control de bajo impacto ambiental sobre Anastrepha fraterculus (Diptera: Tephritidae), como la Tecnica del Insecto Esteril (TIE), no existe aun informacion suficiente sobre su biologia, taxonomia y comportamiento. Este trabajo tiene como objetivo evaluar el desempeno de moscas en jaulas de campo a traves del estudio de la competitividad sexual entre machos salvajes (seleccion sexual). Para ello, se muestreo una poblacion de Horco Molle, Tucuman (Argentina). En jaulas de campo se liberaron machos y hembras adultos virgenes para evaluar la competicion por el apareamiento. Se midieron ocho rasgos morfometricos en machos exitosos y no exitosos: ancho de la cabeza, ancho de la cara, largo del ojo, largo del torax, largo del ala, ancho del ala, largo del femur y largo de la tibia. Se realizaron analisis morfometricos para determinar la relacion entre el fenotipo multivariado y el exito copulatorio. Para evaluar la seleccion sexual sobre el fenotipo del macho se utilizaron diferentes combinaciones de metodos estadisticos multivariados y analisis graficos. Los resultados demostraron que el ancho de ala y el largo de torax serian los blancos mas probables de seleccion sexual, y describen una asociacion no lineal entre el exito copulatorio y cada uno de estos dos rasgos. Dicha asociacion sugiere que la seleccion observada mantendria la diversidad para el tamano del cuerpo. (author)« less

Are PTH levels related to oxidative stress and inflammation in chronic kidney disease patients on hemodialysis?

PubMed

Jaqueto, Marcel; Delfino, Vinicius Daher Alvares; Bortolasci, Chiara Cristina; Barbosa, Decio Sabbatini; Morimoto, Helena Kaminami; Frange, Raquel Ferreira Nassar; Ferreira, Larissa França Fontoura; Guimarães, Fernanda Burle Dos Santos

2016-01-01

Patients at end stage renal disease have higher levels of inflammation and oxidative stress than the general population. Many factors contribute to these issues, and the parathyroid hormone (PTH) is also implicated. The study was conducted in order to assess the relationship between PTH levels and inflammation and oxidative stress in hemodialysis patients. Cross-sectional study with patients of two hemodialysis facilities in Londrina, Brazil. Patients with other conditions known to generate oxidative stress and inflammation were excluded. Blood levels of PTH and biochemical parameters of inflammation (interleukins 1 and 6, tumor necrosis factor-alpha) and oxidative stress (total plasma antioxidant capacity, malonic dialdehyde, lipid hydroperoxidation, advanced oxidation protein products, quantification of nitric oxide metabolites, and 8-isoprostane) were measured before a dialysis session. Then, we made correlation analyses between PTH levels - either as the continuous variable or categorized into tertiles-, and inflammatory and oxidative stress biomarkers. PTH did not show any correlation with the tested inflammation and oxidative stress parameters, nor as continuous variable neither as categorical variable. In this descriptive study, the results suggest that the inflammation and oxidative stress of hemodialysis patients probably arise from mechanisms other than secondary hyperparathyroidism. Pacientes com doença renal em estágio terminal têm níveis de inflamação e estresse oxidativo maiores do que a população geral. Muitos fatores contribuem para isso, e o hormônio paratireoidiano (PTH) é um deles. Estudo foi realizado para avaliar a relação entre os níveis de PTH e níveis de inflamação e estresse oxidativo em pacientes em hemodiálise. estudo transversal com pacientes de duas unidades de hemodiálise de Londrina, Brasil. Pacientes com condições causadoras de inflamação e estresse oxidativo foram exclusos. Níveis plasmáticos de PTH e parâmetros bioquímicos de inflamação (interleucina 1 e 6, fator de necrose tumoral alfa) e estresse oxidativo (capacidade antioxidante plasmática total, dialdeído malônico, hidroperoxidação lipídica, produtos avançados da degradação proteica, quantificação de metabólitos de óxido nítrico e 8-isoprostano) foram dosados antes da sessão de hemodiálise. Realizou-se análise de correlação entre os níveis de PTH - tanto como variável continua como variável categórica em tercis - e os parâmetros de inflamação e estresse oxidativo. Não houve correlação do PTH com nenhum dos parâmetros testados, nem como variável contínua, nem como categórica. Neste estudo descritivo, os resultados sugerem que a inflamação e o estresse oxidativo em pacientes em hemodiálise provavelmente tem origem em mecanismos que não incluem o hiperparatireoidismo secundário.

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.

Como Podar Arboles (Spanish Version), How to Prune Trees

Treesearch

Maureen McDonough; Russell; Lisa Burban; Lee Nancarrow; United States Department of Agriculture, Forest Service, Northeastern Area, State and Private Forestry

2004-01-01

Introduccion, El proposito de la poda es tener plantas fuertes, sanas y atractivas. Esta meta se puede alcanzar sabiendo como, cuando y por que podar, y siguiendo unos cuantos principios muy sencillos.

Religiosidade, juventude e sexualidade: entre a autonomia e a rigidez1

PubMed Central

Silva, Cristiane Gonçalves da; Santos, Alessandro Oliveira; Licciardi, Daniele Carli; Paiva, Vera; Parker, Richard

2009-01-01

Esse artigo descreve como jovens religiosos e autoridades religiosas de sua comunidade compreendem a sexualidade, considerando suas experiências pessoais e como membros de comunidades religiosas. A análise pretende contribuir para que políticas públicas dedicadas à promoção da saúde sexual da juventude considerem a religiosidade, no contexto de um estado laico e da promoção do direito à prevenção. Foram realizadas 26 entrevistas abertas e semidirigidas em diferentes comunidades da região metropolitana da cidade de São Paulo (comunidades católicas, da umbanda, do candomblé e de diferentes denominações evangélicas) sobre iniciação sexual, casamento, gravidez, contracepção e prevenção das DST/Aids, homossexualidade, aborto e direitos humanos. Observou-se como jovens e autoridades religiosas convivem com a tensão entre tradição e modernidade e os distintos discursos sobre a sexualidade. Como sujeitos religiosos (do discurso religioso) e sujeitos sexuais (de discursos sobre sexualidade), devem ser incorporados pelos programas como sujeitos de direito nos termos de sua religiosidade. PMID:21886456

Microwave effects on NiMoS and CoMoS single-sheet catalysts.

PubMed

Borges, I; Silva, Alexander M; Modesto-Costa, Lucas

2018-05-04

Single-sheet nanoclusters of MoS 2 , NiMoS or CoMoS are widely used in hydrodesulfurization (HDS) catalysis in the petroleum industry. In HDS reactions under microwave irradiation, experiments indirectly pointed out that for pristine MoS 2 reaction rates are accelerated because hot spots are generated on the catalyst bed. In this work, we investigated NiMoS and CoMoS isolated single-sheet substituted catalysts before and after thiophene adsorption focusing on quantifying the effect of microwave irradiation. For that purpose, density functional theory (DFT) molecular charge densities of each system were decomposed according to the distributed multipole analysis (DMA) of Stone. Site dipole values of each system were directly associated with a larger or smaller interaction with the microwave field according to a proposed general approach. We showed that microwave enhancement of HDS reaction rates can occur more efficiently in the CoMoS and NiMoS promoted clusters compared to pristine MoS 2 in the following order: CoMoS > NiMoS > MoS 2 . The atomic origin of the catalyst hot spots induced by microwaves was clearly established in the promoted clusters.

Dicloruro de paraquat

EPA Pesticide Factsheets

El dicloruro de paraquat, comúnmente conocido como “paraquat,” es uno de los herbicidas registrados de mayor uso en los Estados Unidos. El paraquat también se conoce como Gramaxone (un producto popular de uso final

Evolution of the Active Phase of CoMo/Al2O3 Catalysts under Industrial Conditions: a High-Pressure MES Study

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

Dugulan, A.I.; Overweg, A.R.; Craje, M.W.J.

2005-04-26

The behavior of CoMo/Al2O3 catalysts sulfided in H2S/H2 gas mixture, under industrial conditions, was investigated using Moessbauer emission spectroscopy (MES). An intermediate Co-Mo phase is formed after increasing the sulfidation pressure to 4 MPa, favoring the Co-Mo-S phase formation. An increase in the quadrupole splitting value of the Co-sulfide species after treatment at 573 K is proposed as a prerequisite for the formation of ideal Co-Mo-S structures.

Catalytic functionalities of supported sulfides. I. Effect of support and additives on the CoMo catalyst

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

Muralidhar, G.; Massoth, F.E.; Shabtai, J.

1984-01-01

C-S hydrogenolysis (HDS) of thiophene, hydrogenation (HYD) of 1-hexene, and hydrocracking (HCG) of 2,4,4-trimethyl-1-pentene, were used as separate model test reactions to differentiate and assess the catalytic functionalities of sulfided CoMo catalysts, and their dependence on the nature of the support and incorporation of additives. Rate constants and relative catalyst activities for these three reaction types were determined. HDS and HYD activities of CoMo supported on different types of Al/sub 2/O/sub 3/ were higher, while the HCG activity was lower compared with CoMo supported on SiO/sub 2/-Al/sub 2/O/sub 3/, SiO/sub 2/-MgO, or TiO/sub 2/. For SiO/sub 2/-Al/sub 2/O/sub 3/ supportsmore » both HDS and HYD activities decreased with increase in SiO/sub 2/ content from 10 to 75%, while HCG activity showed the opposite trend. Additives to a finished CoMo catalyst at 0.5% level caused variations in HDS and HCG activities, while HYD was essentially unaffected. HDS was promoted by NH/sub 4/HF/sub 2/ and NH/sub 4/Cl, but depressed by NaNO/sub 3/, Ca(NO/sub 3/)/sub 2/, and H/sub 3/BO/sub 3/. HCG was promoted by NH/sub 4/HF/sub 2/, NH/sub 4/Cl, and H/sub 3/BO/sub 3/. Additives at 5% level, prior to or after CoMo impregnation, showed a strong depressing effect on HDS and a lesser effect on HYD, while HCG was strongly promoted by NH/sub 4/HF/sub 2/, Ti isopropoxide, and H/sub 3/BO/sub 3/. The changes in catalytic functionalities are rationalized in terms of different interactions between CoMo phase, support, and additives. 3 tables, 1 figure.« less

Sistema Solar: de la observación de La Tierra a los planetas gigantes y sus lunas

NASA Astrophysics Data System (ADS)

Rodrigo, R.

La fotoquímica tiene un papel principal en la composición de las atmósferas planetarias. Se examinan diferentes procesos fotoquímicos tanto para atmósferas oxidadas como reductoras, poniendo un especial énfasis en los ciclos químicos más importantes. En este sentido, se presentan diferentes ciclos químicos capaces de producir hidrocarbonos y nitrilos en atmósferas reductoras, así como aquellos capaces de mantener las proporciones de mezcla de las moléculas que contienen oxígeno, tales como CO2, O2 y H2O. También se analizan otros procesos importantes tales como la condensación y procesos de sputtering y de sublimación que han de tenerse en cuenta cuando se realizan modelos sobre la composición atmosférica.

The Danger from the Outer Space. (Breton Title: O Perigo que Vem do Espaço.) El Peligro que Viene del Espacio

NASA Astrophysics Data System (ADS)

Bedaque, Paulo

2005-12-01

Among the several risks to which the terrestrial life is subject, there is a remote possibility of collision with minor astronomical bodies such as comets and asteroids, which can potentially cause consequences ranging from minor damages to large cataclysms with reflections for the whole Earth. The frequency of the collisions is smaller whenever the external bodies are bigger and more massive. It is possible to conduct simulations taking into account these factors and the velocities and angles of the collisions to estimate their probabilities, the consequences for our planet and the frequency of such events. The results of the simulations are presented graphically to facilitate the final analysis. Finally, we point out that there are several research centers in the world working in the surveillance of the sky to identify possible "aggressive" bodies and evaluate the actual risks for the planet.

Entre os muitos riscos que corre o ambiente terrestre, existe a possibilidade, ainda que remota, de choques com pequenos corpos celestes como cometas, asteróides e meteoróides que podem provocar desde pequenas colisões sem grandes conseqüências até cataclismos de enormes dimensões, com reflexos para toda a vida existente na Terra. A taxa das colisões, como era de se esperar, é tanto maior quanto menores forem as dimensões e a massa do corpo externo. É possível fazer simulações levando-se em conta o diâmetro médio do objeto celeste, sua densidade, a velocidade e o ângulo de colisão para estimar as conseqüências que trariam tais colisões. É possível também estimar ampère probabilidades dos choques e avaliar os reais riscos que nosso planeta corre e com que periodicidade podemos esperá-los. Os resultados dessas simulações aparecem em gráficos de modo a facilitar a analise final. Por fim, lembramos que existem centros de pesquisa em várias partes do mundo trabalhando no patrulhamento do céu na busca de possíveis "agressores" e na estimativa dos reais riscos que corremos. Entre los muchos riesgos que corre el ambiente terrestre existe la remota posibilidad de choques con pequeños cuerpos celestes como cometas y asteroides, y que pueden provocar desde pequeños daños sin mayores consecuencias hasta cataclismos de grandes dimensiones, con reflejos para toda la vida existente enla Tierra. Latasa de colisiones, como era de esperar, es mucho menor para cuerpos con masas y diámetros crecientes. Es posible realizar simulaciones considerando el diámetro, la masa, su velocidad y el ángulo de la colisión para estimar las probabilidades, las consecuencias para el planeta y con qué tasa temporal podemos esperarlas. Los resultados de estas simulaciones se presentan en gráficos para facilitar el análisis final. Finalmente señalamos que existen varios centros de investigación en el mundo trabajando en barreduras del cielo en busca de posibles "agresores" y en las estimaciones de los riesgos que corremos.

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

PubMed Central

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

2017-01-01

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

78 FR 38287 - Bitterroot National Forest, Darby Ranger District, Como Forest Health Project

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-26

... DEPARTMENT OF AGRICULTURE Forest Service Bitterroot National Forest, Darby Ranger District, Como Forest Health Project AGENCY: Forest Service. ACTION: Notice; Correction. SUMMARY: The Department of Agriculture (USDA), Forest Service, Bitterroot National Forest, Darby Ranger District published a document in...

78 FR 36163 - Bitterroot National Forest, Darby Ranger District, Como Forest Health Project

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-17

... Lake Como and Lost Horse Roads, about XX miles northwest of Darby in Ravalli County, Montana. The... Lost Horse Road, about three miles northwest of Darby, Montana (R22W,T4N, Sec. 13, 24, 25, 36; R21W,T4N...

Recent DDT and PCB contamination in the sediment and biota of the Como Bay (Lake Como, Italy).

PubMed

Bettinetti, R; Quadroni, S; Boggio, E; Galassi, S

2016-01-15

Due to its peculiar geographical and morphological characteristics, Lake Como (Northern Italy) represents an interesting study-case for investigating the sub-basin scale circulation of persistent organic pollutants (POPs) that, despite being banned since the 1970s, have reached surprisingly high concentrations in some southern alpine lakes as a consequence of their release from melting glaciers in recent years. In particular, the Como Bay, which is located in the city of Como, seems noteworthy because its waters have a longer residence time than the other areas of the lake. The analyses of the historical concentration of PCBs, pp′DDT and its metabolites in a sediment core sampled from the Como Bay covering a time-period from their ban to recent times, showed that the DDTs have never experienced a significant (p < 0.05) decrease over time, with concentrations of the most abundant homologue, pp′DDE, ranging from 27 to 75 ng g(-1) d.w. Conversely PCBs significantly (p < 0.05) decreased towards recent times, reaching concentrations around 80 ng g(-1) d.w. The contribution of high altitude and local sources was recorded also in the food web: both zooplankton and the zooplanktivorous fish agone were mainly contaminated by pp′DDE (81.4 ng g(-1) w.w. and 534.6 ng g(-1) w.w. respectively) and by the PCB metabolite hexa-CB (449.7 ng g(-1) w.w. and 1672.1 ng g(-1) w.w. respectively). The DDT concentrations in the agone (sampled during the years 2006–2009) never exceeded the limits for human consumption in Italy, while concentrations of six selected PCBs exceeded human health advisory recommendations in one of the fish samples analysed, when it was approximately two times higher than the recommended value of 125 ng g(-1) w.w.

Helenistic Encomium: A Reflection on Comics and Rhetoric

ERIC Educational Resources Information Center

Helms, Jason

2009-01-01

This video reflection starts in a presentation on comics at the Thomas R. Watson Conference last October, which prompted the author to explore the etymology of cosmos and comos through an alternate reading of Gorgias' "Encomium of Helen". The author then works with comos, as revelry, to offer thoughts on comics as a form of multimodal composition…

DESAFÍOS ÉTICOS DE LA INVESTIGACIÓN CON ANIMALES, MANIPULACIÓN GENÉTICA

PubMed Central

Yunta, Eduardo Rodríguez

2012-01-01

En la investigación con animales existen cuestionamientos éticos tanto en el uso como modelos de enfermedades humanas y requisito previo para ensayos en humanos como en la introducción de modificaciones genéticas. Algunos de estos cuestionamientos son: no representar exactamente la condición humana como modelos, realizar pruebas de toxicidad con grave daño para los animales, alterar su naturaleza mediante modificaciones genéticas, riesgos de la introducción de organismos genéticamente modificados. El uso de animales en investigación para beneficio humano, impone al ser humano la responsabilidad moral de respetarlo, no haciéndoles sufrir innecesariamente, al estar trabajando con seres vivientes y sentientes. PMID:23338641

Cúmulos globulares como trazadores de bimodalidad estelar en galaxias cD

NASA Astrophysics Data System (ADS)

Forte, J. C.

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

Estudio multifrecuencia del medio interestelar cercano a HD 192281

NASA Astrophysics Data System (ADS)

Arnal, E. M.; Cappa, C.; Cichowolski, S.; Pineault, S.; St-Louis, N.

Una de las causas que modifica la estructura y dinámica del medio interestelar es la acción que los vientos de las estrellas de gran masa ejercen sobre el mismo. En este trabajo, mediante el uso de datos interferométricos obtenidos en la banda de radio en la transición de 21-cm del Hidrógeno neutro y de imágenes de la emisión de continuo en las bandas de 408 y 1420 MHz, de imágenes HIRES del satélite IRAS en 60 y 100 micrones, y de observaciones de continuo obtenidas con radiotelescopios de disco simple en 2695, 4850 y 8350 MHz se ha realizado un estudio multifrecuencia de los efectos que los vientos estelares de HD 192281, una estrella de tipo espectral O5 Vn((f))p, han tenido sobre el medio interestelar que rodea a la misma.

Estudio multifrecuencia del medio interestelar cercano a HD 192281

NASA Astrophysics Data System (ADS)

Arnal, E. M.; Cappa, C. E.; Cichowolski, S.; Pineault, S.; St-Louis, N.

Una de las causas que modifica la estructura y dinámica del medio interestelar es la acción que los vientos de las estrellas de gran masa ejercen sobre el mismo. En este trabajo, mediante el uso de datos interferométricos obtenidos en la banda de radio en la transición de λ˜21-cm del hidrógeno neutro y de imágenes de la emisión de continuo en las bandas de 408 y 1420 MHz, de imágenes HIRES del satélite IRAS en 60 y 100μm, y de observaciones de continuo obtenidas con radiotelescopios de disco simple en 2695, 4850 y 8350 MHz se ha realizado un estudio multifrecuencia de los efectos que los vientos estelares de HD 192281, una estrella de tipo espectral O5,Vn((f))p, han tenido sobre el medio interestelar que rodea a la misma.

Extraterrestrial hydrogeology

NASA Astrophysics Data System (ADS)

Baker, Victor R.; Dohm, James M.; Fairén, Alberto G.; Ferré, Ty P. A.; Ferris, Justin C.; Miyamoto, Hideaki; Schulze-Makuch, Dirk

2005-03-01

Subsurface water processes are common for planetary bodies in the solar system and are highly probable for exoplanets (planets outside the solar system). For many solar system objects, the subsurface water exists as ice. For Earth and Mars, subsurface saturated zones have occurred throughout their planetary histories. Earth is mostly clement with the recharge of most groundwater reservoirs from ample precipitation during transient ice- and hot-house conditions, as recorded through the geologic and fossilized records. On the other hand, Mars is mostly in an ice-house stage, which is interrupted by endogenic-driven activity. This activity catastrophically drives short-lived hydrological cycling and associated climatic perturbations. Regional aquifers in the Martian highlands that developed during past, more Earth-like conditions delivered water to the northern plains. Water was also cycled to the South Polar Region during changes in climate induced by endogenic activity and/or by changes in Mars' orbital parameters. Venus very likely had a warm hydrosphere for hundreds of millions of years, before the development of its current extremely hot atmosphere and surface. Subsequently, Venus lost its hydrosphere as solar luminosity increased and a run-away moist greenhouse took effect. Subsurface oceans of water or ammonia-water composition, induced by tidal forces and radiogenic heating, probably occur on the larger satellites Europa, Ganymede, Callisto, Titan, and Triton. Tidal forces operating between some of the small bodies of the outer solar system could also promote the fusion of ice and the stability of inner liquid-water oceans. Les processus de subsurface impliquant l'eau sont communs pour les corps planétaires du système solaire et sont très probables sur les exoplanètes (planètes en dehors du système solaire). Pour plusieurs objets du systèmes solaire, l'eau de subsurface est présente sous forme de glace. Pour la Terre et Mars, les zones saturées de subsurface apparaissent à travers toute leur histoire planétaire. La Terre est particulièrement clémente avec la recharge des réservoirs, avec de amples précipitations, des conditions glaciaires et de fortes chaleurs, comme l'atteste les enregistrements géologiques et paléontologiques. D'un autre côté, Mars se trouve dans une phase essentiellement glaciaire, qui est interrompue par des activités contraintes par les phénomènes endogéniques. Cette activité conduit de manière catastrophique à des cycles hydrologiques et à des perturbations climatiques brutaux. Les aquifères régionaux dans les haute terres martiennes qui se sont formés dans des conditions similaires aux conditions terrestres, alimentent les plaines du Nord. L'eau a également été déplacée vers le Pôle Sud martien durant des changements marqués par une forte activité endogénique et une modification des paramètres de l'orbite de Mars. Venus possèdait vrais emblablement une hydrosphère chaude durant des millions d'année, avant le développement de son atmosphère et sa surface particulièrement chaude. Par après Venus a perdit son hydrosphère alors que la luminosité solaire augmentait et qu'une humidité liée à un effet de serre s'installait. Les océans de subsurface d'eau ou d'eau ammoniacale, induits par les forces de marée et le chauffage radiogénique, apparaissent probablement sur les satellites les plus importants (Europa, Ganymede, Callisto, Titan, Triton). Les forces de marée entre les petits corps externes du système solaire peuvent également occasionner la fusion de glace et la stabilité des océans internes d'eau liquide. Los procesos hídricos subsuperficiales son comunes en cuerpos planetarios del sistema solar y son altamente probables para exoplanetas (planetas fuera del sistema solar). Para muchos cuerpos del sistema solar, el agua subsuperficial existe como hielo. Para la Tierra y Marte han ocurrido zonas saturadas subsuperficiales a través de sus historias planetarias. La Tierra es principalmente generosa con la recarga de la mayoría de reservorios de aguas subterráneas a partir de amplia precipitación reconocida en condiciones transitorias calientes y heladas, tal y como aparece en los registros fósiles y geológicos. Por otro lado, Marte se encuentra principalmente en una etapade cámara de hielo la cual es interrumpida por actividad de tipo endogénico. Esta actividad pone en funcionamiento catastróficamente ciclos hidrológicos de vida corta y perturbaciones climáticas asociadas. Acuíferos regionales en las montañas de Marte que se desarrollaron en el pasado en condiciones similares a la Tierra distribuyen agua a las planicies del norte. El agua ha sido transportada hacia el sur de la región polar durante cambios en el clima inducidos por actividad endogénica y/o cambios en los parámetros orbitales de Marte. Venus muy probablemente tuvo una hidrósfera caliente durante cientos de millones de años, antes de que se desarrollara su atmósfera y superficie actual extremadamente caliente. Subsecuentemente, Venus perdió su hidrósfera a medida que la luminosidad solar aumentó y un efecto de invernadero húmedo escapatorio se llevó a cabo. Océanos subsuperficiales de composición agua o amoniaco-agua, inducidos por fuerzas de marea y calentamiento radiogénico, probablemente ocurren en los satélites más grandes como Europa, Ganimeda, Callisto, Titan y Triton. Las fuerzas de marea que operan entre los cuerpos pequeños del sistema solar externo podrían también promover la fusión de hielo y la estabilidad de líquido interno-aguas de los océanos.

Velocidades radiales en Collinder 121

NASA Astrophysics Data System (ADS)

Arnal, M.; Morrell, N.

Se han llevado a cabo observaciones espectroscópicas de unas treinta estrellas que son posibles miembros del cúmulo abierto Collinder 121. Las mismas fueron realizadas con el telescopio de 2.15m del Complejo Astronómico El Leoncito (CASLEO). El análisis de las velocidades radiales derivadas del material obtenido, confirma la realidad de Collinder 121, al menos desde el punto de vista cinemático. La velocidad radial baricentral (LSR) del cúmulo es de +17 ± 3 km.s-1. Esta velocidad coincide, dentro de los errores, con la velocidad radial (LSR) de la nebulosa anillo S308, la cual es de ~20 ± 10 km.s-1. Como S308 se encuentra físicamente asociada a la estrella Wolf-Rayet HD~50896, es muy probable que esta última sea un miembro de Collinder 121. Desde un punto de vista cinemático, la supergigante roja HD~50877 (K3Iab) también pertenecería a Collinder 121. Basándonos en la pertenencia de HD~50896 a Collinder 121, y en la interacción encontrada entre el viento de esta estrella y el medio interestelar circundante a la misma, se estima para este cúmulo una distancia del orden de 1 kpc.

Uso de terreno urbano y rural en Puerto Rico

Treesearch

Sebastian Martinuzzi; William A. Gould; Olga M. Ramos Gonzalez; Maya Quinones; Michael E. Jimenez

2008-01-01

El Proyecto de Analisis de Gap de Puerto Rico (PRGAP) (Gould et al. 2008) desarrollo tres usos de terrenos para Puerto Rico: Urbano, Suburbano, y Rural (Martinuzzi et al. 2007). Estas regiones tambien pueden ser consideradas como urbano, densamente-poblado rural, y escasamente-poblado rural, o como urbano y area silvestre con una interfase de area silvestre-urbana. La...

M S MOLECULARES Rumo aos limites da miniaturiza o - (Molecular Magnets - towards the limits of miniaturization)

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

Reis, Mario S; Moreira Dos Santos, Antonio F

Por s culos, acreditou-se que o magnetismo s se manifestava em metais, como aqueles contendo ferro; hoje, a imagem mais comum de um m talvez seja a daquelas plaquinhas flex veis coladas geladeira com propagandas dos mais diversos tipos. O leitor conseguiria imaginar um material puramente org nico daqueles que formam os seres vivos como magn tico? E m s do tamanho de mol culas? fato: ambos existem. Esses novos materiais, conhecidos como magnetos moleculares, descobertos e desenvolvidos em v rios laborat rios do mundo, j re nem longa lista de aplica es, do tratamento do c ncer a refrigeradoresmore » ecol gicos, passando pela transmiss o de eletricidade sem perda de calor e a fabrica o de computadores extremamente velozes.« less

Populações estelares do bojo galáctico

NASA Astrophysics Data System (ADS)

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

2003-08-01

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

Proceedings of the Fourth Symposium on Conference on Dynamics of Cosmic Gases, Varenna Italy (Lake of Como), August 18-30, 1960; ATTI DEL IV SYMPOSIUM SULLA DINAMICA DEL GAS COSMICO, VARENNA SUL LAGO DI COMO 18-30 AGOSTO 1960

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

None

1961-01-01

Fifteen papers are included: separate abstracts have been prepared for l0. A single abstract has been prepared to cover the remaining 5 papers, which consist of observational studies. Extensive discussions are included. (T.F.H.)

Cardiac Magnetic Resonance-Verified Myocardial Fibrosis in Chagas Disease: Clinical Correlates and Risk Stratification.

PubMed

Uellendahl, Marly; Siqueira, Maria Eduarda Menezes de; Calado, Eveline Barros; Kalil-Filho, Roberto; Sobral, Dário; Ribeiro, Clébia; Oliveira, Wilson; Martins, Silvia; Narula, Jagat; Rochitte, Carlos Eduardo

2016-11-01

Chagas disease (CD) is an important cause of heart failure and mortality, mainly in Latin America. This study evaluated the morphological and functional characteristics of the heart as well the extent of myocardial fibrosis (MF) in patients with CD by cardiac magnetic resonance (CMR). The prognostic value of MF evaluated by myocardial-delayed enhancement (MDE) was compared with that via Rassi score. This study assessed 39 patients divided into 2 groups: 28 asymptomatic patients as indeterminate form group (IND); and symptomatic patients as Chagas Heart Disease (CHD) group. All patients underwent CMR using the techniques of cine-MRI and MDE, and the amount of MF was compared with the Rassi score. Regarding the morphological and functional analysis, significant differences were observed between both groups (p < 0.001). Furthermore, there was a strong correlation between the extent of MF and the Rassi score (r = 0.76). CMR is an important technique for evaluating patients with CD, stressing morphological and functional differences in all clinical presentations. The strong correlation with the Rassi score and the extent of MF detected by CMR emphasizes its role in the prognostic stratification of patients with CD. A doença de Chagas (DC) é importante causa de insuficiência cardíaca e mortalidade, principalmente na América Latina. Este estudo avaliou as características morfológicas e funcionais do coração, assim como a extensão da fibrose miocárdica (FM) em pacientes com DC através de ressonância magnética cardíaca (RMC). O valor prognóstico da FM avaliada por realce tardio miocárdico (RTM) foi comparado àquele do escore de Rassi. Avaliação de 39 pacientes divididos em 2 grupos: grupo 'forma indeterminada' (IND), 28 pacientes assintomáticos; e grupo 'cardiopatia chagásica' (CC), pacientes sintomáticos. Todos os pacientes foram submetidos a RMC com as técnicas de cine-RM e RTM, sendo a quantidade de FM evidenciada ao exame comparada ao escore de Rassi. As análises morfológica e funcional mostraram significativas diferenças entre os 2 grupos (p < 0,001). Houve ainda uma forte correlação entre a extensão da FM e o escore de Rassi (r = 0,76). A RMC é uma importante técnica para avaliar pacientes com DC, ressaltando as diferenças morfológicas e funcionais em todas as apresentações clínicas. A forte correlação entre o escore de Rassi e a extensão da FM detectada por RMC enfatiza seu papel na estratificação prognóstica de pacientes com DC.

On Ensino de Astronomia: Desafios para Implantação

NASA Astrophysics Data System (ADS)

Faria, R. Z.; Voelzke, M. R.

2008-09-01

Em 2002 o ensino de Astronomia foi proposto como um dos temas estruturadores pelos Parâmetros Curriculares Nacionais e sugerido como facilitador para que o aluno compreendesse a Física como construção humana e parte do seu mundo vivencial, mas raramente seus conceitos foram ensinados. A presente pesquisa discute dois aspectos relacionados à abordagem de Astronomia. O primeiro aspecto é se ela está sendo abordada pelos professores do Ensino Médio e o segundo, aborda a maneira como ela está sendo ensinada. Optou-se pela aplicação de um questionário a partir do 2° semestre de 2006 e durante o ano de 2007 com professores que ministram a disciplina de Física, os quais trabalham em escolas estaduais em Rio Grande da Serra, Ribeirão Pires e Mauá no estado São Paulo. Dos 66,2% dos professores que responderam ao questionário nos municípios de Rio Grande da Serra, Ribeirão Pires e Mauá, 57,4% não aplicaram nenhum tópico de astronomia, 70,2% não utilizaram laboratório, 89,4% não utilizaram qualquer tipo de programa computacional, 83,0% nunca fizeram visitas com alunos a museus e planetários e 38,3% não indicaram qualquer tipo de livro ou revista referente à astronomia aos seus alunos. Mesmo considerando a Astronomia um conteúdo potencialmente significativo, esta não fez parte dos planejamentos escolares. Portanto são necessárias propostas que visem estratégias para a educação continuada dos professores como, por exemplo, cursos específicos sobre o ensino em Astronomia.

LA BIOÉTICA COMO QUEHACER FILOSÓFICO

PubMed Central

Ferrer, Jorge José

2009-01-01

El artículo examina el estatuto epistemológico de la bioética como disciplina académica. El autor sostiene que el estatuto epistemológico de un discurso lo determina la pregunta fundamental que se plantea y la respuesta que se busca, focos integradores del discurso. En el caso de la bioética, la pregunta fundamental es de índole moral. La bioética es pues una disciplina ética que tiene su hogar epistemológico en la filosofía. El autor también defiende el concepto de “éticas aplicadas”. Sugiere finalmente que el método de la bioética, sobre todo la que se hace desde nuestras latitudes, debería adoptar el círculo hermenéutico como metodología para su filosofar. PMID:20463860

Como preparar un programa de informacion sobre la asistencia economica (Planning a Financial Aid Awareness Program).

ERIC Educational Resources Information Center

Department of Education, Washington, DC.

This booklet, written in Spanish, is intended to be used with a set of slides as part of a presentation to students on "How To Apply for Federal Student Aid" ("Como Solicitar la Asistencia Economica Federal para Estudiantes"). The first part of the book is a script based on the slides. After the script is a guide to hosting a financial aid…

Patient survival and risk of death after prostate cancer treatment in the Brazilian Unified Health System.

PubMed

Braga, Sonia Faria Mendes; Souza, Mirian Carvalho de; Oliveira, Raphael Romie de; Andrade, Eli Iola Gurgel; Acurcio, Francisco de Assis; Cherchiglia, Mariangela Leal

2017-05-15

Analyze the probability of specific survival and factors associated with the risk of death of patients with prostate cancer who received outpatient cancer treatment in the Brazilian Unified Health System, Brazil. Retrospective cohort study using the National Database of Oncology, developed through the deterministic-probabilistic pairing of health information systems: outpatient (SIA), hospital (SIH) and mortality (SIM). The probability of overall and specific survival was estimated by the time elapsed between the date of the first ambulatory treatment, from 2002 to 2003, until the patient's death or the end of the study. Fine and Gray's model of competing-risks regression was adjusted according to the variables: age of diagnostic, region of residence, tumor clinical staging, type of outpatient cancer treatment and hospitalization in the assessment of factors associated with risk of patient death. Of 16,280 patients studied, the average age was 70 years, approximately 25% died due to prostate cancer and 20% for other causes. The probability of overall survival was 0.50 (95%CI 0.49-0.52) and the specific was 0.70 (95%CI 0.69-0.71). The factors associated with the risk of patient death were: stage III (HR = 1.66; 95%CI 1.39-1.99) and stage IV (HR = 3.49; 95%CI 2.91-4.18), chemotherapy (HR = 2.34; 95%CI 1.76-3.11) and hospitalization (HR = 1.6; 95%CI 1.55-1.79). The late diagnosis of the tumor, palliative treatments, and worse medical condition were factors related to the worst survival and increased risk of death from prostate cancer patients in Brazil. Analisar a probabilidade de sobrevida específica e os fatores associados ao risco de óbito dos pacientes com câncer de próstata, que receberam tratamento oncológico ambulatorial no SUS, Brasil. Estudo de coorte retrospectivo utilizando a Base Nacional em Oncologia, desenvolvida por meio de pareamento determinístico-probabilístico dos sistemas de informação de saúde: ambulatorial (SIA), hospitalar (SIH) e de mortalidade (SIM). A probabilidade de sobrevida global e específica foi estimada pelo tempo decorrido entre a data do primeiro tratamento ambulatorial, entre 2002 e 2003, até o óbito dos pacientes ou fim do estudo. O modelo de regressão de riscos competitivos de Fine e Gray foi ajustado segundo as variáveis: idade ao diagnóstico, região de residência, estadiamento clínico do tumor, tipo de tratamento oncológico ambulatorial e internação na avaliação dos fatores associados ao risco de óbito dos pacientes. Dos 16.280 pacientes estudados, a idade média foi de 70 anos, cerca de 25% foi a óbito devido ao câncer de próstata e 20% por outras causas. A probabilidade de sobrevida global foi de 0,50 (IC95% 0,49-0,52) e a específica 0,70 (IC95% 0,69-0,71) . Os fatores associados ao risco de óbito dos pacientes foram: estádio III (HR = 1,66; IC95% 1,39-1,99) e estágio IV (HR = 3,49; IC95% 2,91-4,18), tratamento quimioterápico (HR = 2,34; IC95% 1,76-3,11) e internação (HR = 1,6; IC95% 1,55-1,79). O diagnóstico tardio do tumor, tratamentos não curativos e pior condição clínica foram fatores relacionados à pior sobrevida e ao maior risco de óbito dos pacientes com câncer próstata no Brasil.

Estimaciones de cambio climatico para Michoacan: Implicaciones para el sector agropecuario y forestal y para la conservacion de la Mariposa Monarca [In Spanish

Treesearch

Cuauhtemoc Saenz-Romero; Gerald E. Rehfeldt; Nicholas L. Crookston; Pierre Duval; Jean Beaulieu

2009-01-01

El cambio climatico, conocido comunmente como calentamiento global, es el incremento de la temperatura a nivel mundial y los cambios que de ello derivan, causados por el "efecto invernadero" del bioxido de carbono (CO2) y otros gases emitidos a la atmosfera. El uso de combustibles fosiles (carbon y derivados del petroleo, como gasolina, diesel, combustoleo y...

Percepção Astronômica de Alunos do Ensino Médio da Rede Estadual de São Paulo

NASA Astrophysics Data System (ADS)

de Oliveira, E. F.; Voelzke, M. R.; Amaral, L. H.

2005-08-01

Embora a astronomia seja uma das ciências mais antigas da humanidade e muitos dos conceitos astronômicos serem populares, principalmente nesta época de alta globalização do conhecimento por intermédio de eficientes meios de comunicação e de obtenção da informação, notadamente através da internet, observa-se que uma parcela significativa dos estudantes encontra-se à margem dessas informações. O presente trabalho visa analisar o nível de conhecimento básico dos alunos de Ensino Médio da rede estadual da cidade de Suzano quanto aos fenômenos astronômicos que os rodeiam, tais como a sucessão dos dias e das estações do ano, além de questioná-los sobre fatos genéricos tais como: quais são os astros que se encontram mais próximos do planeta Terra, o que vem a ser o Sol, o Big Bang, um ano-luz, uma estrela cadente, a estrela de Bélem e o que ocasionou a extinção dos dinossauros. Para tanto foi elaborado um formulário constando de questões de múltipla escolha, o qual foi aplicado no primeiro colegial noturno da Escola Estadual Batista Renzi. Num espaço amostral de 34 alunos constatou-se que apenas 29,4% compreendiam a sucessão dos dias da semana, que apenas 20,6% explicaram corretamente as estações do ano, que apenas 20,6% tinham idéia de quais são os objetos celestes mais próximos da Terra, em contraposição 67,6% sabiam classificar corretamente o Sol como estrela, 55,9% relacionavam o Big Bang à origem do universo, apenas 20,6% identificavam um ano-luz como unidade de distância, 32,4% reconheciam uma estrela cadente como meteoro, 41,2% consideravam a estrela de Belém como um cometa e 50,0% explicaram corretamente a extinção dos dinossauros. A presente análise será expandida para as demais classes de primeiro colegial, não somente do período noturno, mas também do diurno da Escola Estadual Batista Renzi, bem como o formulário será devidamente ampliado. Já nesta primeira fase nota-se claramente o pequeno discernimento de eventos astronômicos dos alunos e principalmente a grande confusão sobre o significado correto de termos astronômicos populares.

Conhecimento Científico e Cotidiano em Astronomia: Uma Investigação com Alunos da Educação Básica

NASA Astrophysics Data System (ADS)

Vieira, J. B.; Longhini, M. D.

2011-12-01

Este texto apresenta resultados de uma investigação que teve como objetivo, investigar como os conhecimentos científicos e do cotidiano relacionados a essa área de conhecimento apresentam na escola de Educação Básica, especialmente, em alunos do Ensino Médio prestes a deixar Educação Básica. Para realização da pesquisa, utilizamos como recurso metodológico a aplicação de um questionário estruturado contendo 47 questões, organizadas em duas categorias: Conhecimento Cotidiano e Conhecimento Científico. As questões da categoria “Conhecimento Cotidiano” possuíam afirmações relacionadas a crendices, contos populares, especulações e temáticas do gênero, as quais, geralmente, estão fora do círculo de discussão da comunidade científica, talvez por não serem consideradas como objeto de estudo da ciência. As questões da categoria “Conhecimento Científico” são relacionadas a conteúdos específicos de Astronomia, as quais são compartilhadas pela comunidade científica e aceitas, pelo menos provisoriamente, como possuindo fundamentação científica. Concluímos que, possuem ainda concepções de temas Astronômicos persistentes à mudança, por exemplo, fases da Lua relacionadas à melhor período para corte de cabelo e também para plantio; estrela cadente e ocasião perfeita para se fazer um pedido. Entretanto, podemos observar no que diz respeito a mitos e superstições, que quase não existe influência destes entre os alunos. Portanto, ao trabalharmos com os alunos determinados conceitos científicos, é importante lembrarmos que o professor não opera no vazio; os alunos são sujeitos de saberes, práticas e, dessa forma constroem e reconstroem saberes. Cabe ao professor ouvir os estudantes reconstruindo junto deles conceitos científicos. Acreditamos que o ensino de Ciências na Educação Básica deve lidar criticamente com o conhecimento cotidiano e científico e, assim, efetivar a Ciência como disciplina educativa, formativa e libertadora.

Gabapentina a dosis de 300 vs. 450 mg como premedicación anestésica para hipertensión reactiva, ansiedad y analgesia.

PubMed

Rascón-Martínez, Dulce María; Guzmán-Sánchez, Joaquín Antonio; Corral-Urdapilleta, Nora Paulina; Arguelles-Uribe, Gema Damaris; Velázquez-Loeza, Jazmín; Soto-Palma, Gustavo; Carrillo-Torres, Orlando

Observar el comportamiento de la gabapentina para aminorar la hipertensión reactiva secundaria a ansiedad y dolor en pacientes sometidos a cirugía oftálmica, así como el consumo de opiáceos entre los grupos. Ensayo clínico controlado aleatorizado y doble ciego que analizó a 125 pacientes divididos en tres grupos: grupo A, gabapentina 300 mg; grupo B, gabapentina 450 mg; grupo C, amaranto en grageas como control 2 horas antes del procedimiento quirúrgico. Se utilizó la prueba de ji al cuadrado para variables sociodemográficas y ANOVA de un factor para variables numéricas continuas. Se consideró como significativo un valor de p < 0.05 para un estudio de dos colas con un poder beta del 80%. La ansiedad y la analgesia transoperatoria y posoperatoria tuvieron diferencias significativas entre los grupos. Se encontró menor consumo de opiáceos en los grupos que usaron gabapentina. La gabapentina por vía oral, 300 o 450 mg, 2 horas antes de la cirugía, reduce el dolor, la ansiedad y el consumo de opiáceos durante el posoperatorio en pacientes sometidos a cirugía oftalmológica. Copyright: © 2018 SecretarÍa de Salud

[Women's complaint leadership in the Causa Kleinwächter. A contribution to patient history of the Innsbruck maternity hospital].

PubMed

Hilber, Marina

On the basis of the Innsbruck Maternity Clinic this paper deals with the individual and collective worlds of experience of obstetric patients. However, not only the patient's view on the proceedings in this specific medical space is being reconstructed, also the prevailing conventions surrounding the treatment of pregnant, parturient and puerperal patients serving as clinical material in obstetric research and education are critically scrutinised. At the centre of this paper stands Dr. Ludwig Kleinwächter's period of duty, who acted as professor for obstetrics and gynaecology in Innsbruck between 1877 and 1881. During this period numerous conflicts regarding the treatment of patients are documented. Concerned about the good reputation of the Maternity Clinic, the Tyrolean State Committee, as the Clinic's provider, tried to solve the crisis. The existing letters of complaint and protocols do not only give a voice to the women concerned, but also to the medical professions as well as the local political representatives involved.

[An information system for injuries from external causes (SILEX): a successful project in El Salvador].

PubMed

Salinas, Oscar; de Cosío, Gerardo; Clavel-Arcas, Carme; Montoya, Jeannette; Serpas, Mario; Morán de García, Silvia; Concha-Eastman, Alberto

2008-12-01

This article examines the stages in developing an information system for injuries from external causes (Sistema de Información de Lesiones de Causa Externa-SILEX), as well as its limitations and achievements. SILEX is a Web-based application for collection, quality control, presentation, and analysis of data available from the hospital system for surveillance of injuries from external causes created by Ministry of Health of El Salvador with data from the hospital emergency services. This system maintains comprehensive information on the injured person-type of injury, intention, injury site, activity being performed at the time of injury, risk factors, etc.-in the form of tables, graphs, and maps, which streamlines the development of intervention plans and prevention initiatives for these types of injuries in El Salvador. This experience is an example of what can be done to close the information gap on injuries by external causes in the Region of the Americas.

Profilaxia de tromboembolismo venoso na gestação

PubMed Central

de Oliveira, André Luiz Malavasi Longo; Marques, Marcos Arêas

2016-01-01

Resumo O tromboembolismo venoso é importante causa de morbidade e mortalidade obstétrica. Durante a gestação, o risco de sua ocorrência aumenta entre cinco e dez vezes quando comparado ao de mulheres não gestantes de mesma idade. Associado a esse fato, a gestante apresenta algumas limitações para o diagnóstico clínico (alta frequência de dor e edema nos membros inferiores), ecográfico (menor sensibilidade e especificidade no diagnóstico de trombose venosa de ilíaca com a evolução da gestação) e laboratorial (o D-dímero apresenta aumento progressivo no decorrer da gravidez). Uma estratificação criteriosa de risco de tromboembolismo venoso de cada mulher antes da gestação pode diminuir a incidência dessa doença, frequente e de difícil diagnóstico na gravidez, e suas complicações. PMID:29930607

Sobrevivendo a un tsunami: lecciones de Chile, Hawai y Japon

USGS Publications Warehouse

Compilado por Atwater, Brian F.; Cisternas V., Marco; Bourgeois, Joanne; Dudley, Walter C.; Hendley, James W.; Stauffer, Peter H.

1999-01-01

Este folleto contiene historias veridicas que ilustran como sobrevivir, y como no sobrevivir, a un tsunami. Esta publicacion esta dirigida a las personas que viven, trabajan o, simplemente, se divierten a lo largo de las costas que pueden ser afectadas por un tsunami. Tales costas rodean la mayor parte del Oceano Pacifico pero tambien incluyen algunas areas costeras de los Oceanos Atlantico e Indico. Aunque mucha gente llama a los tsunamis 'olas de marea', estos no estan relacionados a las mareas, sino son una serie de olas, o 'tren de olas', generalmente causadas por cambios en el nivel del fondo marino durante los terremotos. Los tsunamis tambien pueden ser generados por la erupcion de volcanes costeros, islas volconicas, deslizamientos submarinos e impactos de grandes meteoritos en el mar. Como sucedio en Sumatra en el 2004, los tsunamis pueden alcanzar alturas de 15 metros, no tan solo en la costa sino tambien kilometros tierra adentro. Los relatos presentados en este folleto fueron seleccionados de entrevistas realizadas a personas que sobrevivieron al tsunami del Oceano Pacifico de 1960. Muchas de estas personas, incluyendo a la enfermera de la foto, se enfrento a las olas generadas a poca distancia, en la costa chilena. En cambio, otros debieron hacer frente al tsunami muchas horas despues, en Hawai y Japon. La mayoria de las entrevistas fueron realizadas a fines de los anos ochenta y en los noventa. Las historias ofrecen una mezcla de lecciones de supervivencia a un tsunami. En algunos casos se presentan las acciones que confiablemente salvaron vidas: poner atencion a los avisos de la naturaleza, abandonar los bienes, dirigirse rapidamente a un sector alto y permanecer alli hasta que el tsunami realmente haya terminado. Otras historias describen como se encontro refugio al subir a construcciones y arboles o flotar sobre desechos, tacticas que tuvieron diferentes resultados y que pueden ser recomendadas solo como actos desesperados de personas atrapadas en sectores bajos.

Astronomia Motivadora no Ensino Fundamental

NASA Astrophysics Data System (ADS)

Melo, J.; Voelzke, M. R.

2008-09-01

O objetivo principal deste trabalho é procurar desenvolver o interesse dos alunos pelas ciências através da Astronomia. Uma pesquisa com perguntas sobre Astronomia foi realizada junto a 161 alunos do Ensino Fundamental, com o intuito de descobrir conhecimentos prévios dos alunos sobre o assunto. Constatou-se, por exemplo, que 29,3% da 6ª série responderam corretamente o que é eclipse, 30,0% da 8ª série acertaram o que a Astronomia estuda, enquanto 42,3% dos alunos da 5ª série souberam definir o Sol. Pretende-se ampliar as turmas participantes e trabalhar, principalmente de forma prática com: dimensões e escalas no Sistema Solar, construção de luneta, questões como dia e noite, estações do ano e eclipses. Busca-se abordar, também, outros conteúdos de Física tais como a óptica na construção da luneta, e a mecânica no trabalho com escalas e medidas, e ao utilizar uma luminária para representar o Sol na questão do eclipse, e de outras disciplinas como a Matemática na transformação de unidades, regras de três; Artes na modelagem ou desenho dos planetas; a própria História com relação à busca pela origem do universo, e a Informática que possibilita a busca mais rápida por informações, além de permitir simulações e visualizações de imagens importantes. Acredita-se que a Astronomia é importante no processo ensino aprendizagem, pois permite a discussão de temas curiosos como, por exemplo, a origem do universo, viagens espaciais a existência ou não de vida em outros planetas, além de temas atuais como as novas tecnologias.

Combat Identification Systems COMO Integrated Air Defense Model Evaluation (CISE) Study

DTIC Science & Technology

1989-02-01

use K or IR , whichever one applies) E-6 CAA-SR-89- 3 Subroutine PDECLR 1/21/88 Before label 1000 Insert: IF (IR.GT.10) IR a 10 These changes were made...Internal Distribution: Unclassified Library 2 F-2 CAA-SR-89- 3 GLOSSARY 1. ABBREVIATIONS, ACRONYMS, AND SHORT TERMS ADM2 Air Defense Models Modification...STUDY REPORT ’ , CAA-Sn-89- 3 i , .- CD o COMBAT IDENTIFICATION SYSTEMS N COMO INTEGRATED AIR DEFENSE MODEL EVALUATION (CISE) STUDY FEBRUARY 1989

Neurobiología del autismo y TDAH mediante técnicas de neuroimagen: divergencias y convergencias

PubMed Central

Proal, Erika; Olvera, Jorge González; Blancas, Aurea S.; Chalita, Pablo J.; Castellanos, F. Xavier

2013-01-01

En el área clínica algunos síntomas del trastorno por déficit de atención e hiperactividad (TDAH), se presentan en los pacientes con trastorno del espectro autista (TEA). Se ha demostrado que existen alteraciones en circuitos cerebrales que impactan en fallas cognitivas y de comportamiento específicas de cada uno de estos trastornos. Sin embargo, han sido poco estudiados los correlatos cerebrales que hay detrás tanto de las similitudes como de las diferencias sintomatológicas. En la presente revisión se analizaron los estudios meta-analíticos existentes estructurales y funcionales en TDAH y TEA. Por un lado, se observaron convergencias en circuitos como el dorsal atencional, de funciones ejecutivas, visual, somatomotor y circuito de activación por defecto. Estas similitudes posiblemente explican las manifestaciones comórbidas entre los trastornos como la falla en la integración de información, motricidad fina y procesos atencionales específicos. Por otro lado, específicamente en el TDAH se observan déficits en el circuito de recompensa y ventral atencional, sistemas involucrados en la medición de efectos de reforzamiento y monitoreo atencional. En TEA los circuitos más afectados fueron los implicados en procesos de cognición social y lenguaje. En conclusión, existen correlatos neuronales en TEA que explican las manifestaciones clínicas tanto convergentes como divergentes presentes en TDAH. PMID:23897144

[Not Available].

PubMed

Zubiaga, Lorea; Ruiz-Tovar, Jaime; Giner, Lorena; González, Juan; Aguilar, María Del Mar; García, Alejandro; Calpena, Rafael; Durán, Manuel

2016-07-19

Introducción y objetivo: el IMC puede resultar engañoso para ciertas complexiones corporales, por lo que se han propuesto otros parámetros como la adiposidad (calculada a través de fórmula CUN-BAE,) el índice de Framingham de riesgo cardiovascular (IF) y el índice aterogénico (IA) (rCT/HDL-c) como predictores de riesgo cardiovascular. Se propone comparar estos factores como marcadores de éxito terapéutico tras cirugía en pacientes obesos sometidos a gastrectomía vertical laparoscópica (GVL) como procedimiento de cirugía bariátrica.Material y métodos: realizamos un estudio observacional prospectivo de pacientes sometidos a GVL y con un periodo de seguimiento mínimo de 1 año. Analizamos la evolución de IMC, adiposidad, IF e IA.Resultados: analizamos 140 pacientes. El IMC preoperatorio fue de 49,1 kg/m2, con una adiposidad del 54,8%, un IF 7,54% y un IA de 4,2. A los 12 meses el IMC era de 28,4 kg/m2, con una adiposidad del 39,4%, un IF del 3,7% y un IA de 1,64. En función de estos resultados, a los 12 meses el IMC medio está en rango de sobrepeso, la adiposidad en niveles de obesidad (obesidad: > 25% en hombres y > 35% en mujeres), el IF en rango de riesgo cardiovascular bajo (< 5%) y el IA dentro del rango de normalidad (< 3). Correlacionando estos parámetros observamos que el IMC se correlaciona con la adiposidad tanto en valores preoperatorios (Pearson 0,486; p = 0,004), posoperatorios (Pearson 0,957; p < 0,001), como en la diferencia entre ambos (Pearson 0,606; p = 0,017), lo cual es lógico, porque el IMC se incluye en la fórmula CUN-BAE para el cálculo de la adiposidad. En los valores posoperatorios se objetiva una correlación de la adiposidad con el IF (Pearson 0,814, p = 0,036) y con el IA (Pearson 0,517; p = 0,049). En los valores preoperatorios no se objetivan dichas correlaciones. El IMC no se correlacionó con la adiposidad.Conclusión: la adiposidad se correlaciona con índices de riesgo cardiovascular, como el índice de Framingham o el índice aterogénico, pero solo en las determinaciones posoperatorias. Estos elementos suponen herramientas útiles para valorar la disminución del riesgo de enfermedad cardiovascular después de cirugía bariátrica.

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

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

Diaz Bautista, Gonzalo A.

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

Communicacion Expresiva: Como los ninos nos envian mensajes [and] Comunicacion Receptiva: Como los ninos entienden nuestros mensajes [and] Interacciones de Comunicacion: Hacen falta dos. Hojas informativa de DB-LINK (Communication Interactions: It Takes Two [and] Receptive Communication: How Children Understand Your Messages to Them [and] Expressive Communication: How Children Send Their Messages to You. DB-LINK Fact Sheets).

ERIC Educational Resources Information Center

Stremel, Kathleen

This document consists of three separately published fact sheets combined here because of the close relationship of their subject matter. The first fact sheet, "Communication Interactions: It Takes Two" (Kathleen Stremel), defines communication; suggests ways to find opportunities for interactive communication; offers specific suggestions for…

Intra-aortic balloon pump in cardiogenic shock: state of the art.

PubMed

Thomaz, Petronio Generoso; Moura, Leonel Adelino; Muramoto, Giovana; Assad, Renato Samy

2017-01-01

The clinical definition of cardiogenic shock is that of a low cardiac output and evidence of tissue hypoxia in the presence of adequate blood volume. Cardiogenic shock is the main cause of death related to acute myocardial infarction (AMI), with a mortality rate of 45-70% in the absence of aggressive and highly specialized technical care. The intra-aortic balloon pump (IABP) is one of the most widely used mechanical assisting devices. During the last two decades, about 42% of patients with AMI who evolved with cardiogenic shock received mechanical circulatory assistance with IABP. Its clinical indication has been based on non-randomized studies and registry data. Recent studies have shown that the use of IABP did not reduce 30-day mortality in patients with AMI and cardiogenic shock treated with the strategy of early myocardial revascularization as the planned primary objective. The guidelines of the American Heart Association and of the European Society of Cardiology have reassessed their recommendations based on the results of meta-analyzes, including the IABP-SCHOCK II Trial study, which did not evidence an increase in survival of patients who received mechanical support with IABP. This review article addresses the clinical impact of IABP use in the cardiogenic shock caused by AMI. RESUMO A definição clínica de choque cardiogênico é a de um quadro de baixo débito cardíaco e evidência de hipóxia tecidual, na presença de volemia adequada. O choque cardiogênico representa a principal causa de óbito relacionada ao infarto agudo do miocárdio (IAM), com índice de mortalidade em torno de 45% a 70%, na ausência de cuidados técnicos agressivos e altamente especializados. O balão intra-aórtico (BIA) é um dos dispositivos de assistência mecânica mais utilizados no mundo. Nas duas últimas décadas, cerca de 42% dos pacientes com IAM, que evoluíram com choque cardiogênico, receberam assistência circulatória mecânica com BIA. Sua indicação clínica tem sido baseada em estudos não randomizados e dados de registro. Estudos recentes têm demonstrado que o uso do BIA não reduziu a mortalidade hospitalar (30 dias) em pacientes com IAM e choque cardiogênico, tratados com a estratégia de revascularização precoce do miocárdio como objetivo primário planejado. As diretrizes da Associação Americana de Cardiologia e da Sociedade Europeia de Cardiologia reavaliaram suas recomendações, baseadas nos resultados de metanálises, incluindo o estudo IABP-SCHOCK II Trial, que não evidenciou aumento na sobrevida de pacientes que receberam suporte mecânico com BIA. Este artigo de revisão aborda o impacto clínico do uso do BIA no choque cardiogênico ocasionado pelo IAM.

Estrategia de Aprendizaje Basado en Problemas (ABP) para explorar las concepciones alternativas relacionadas al tema estados de agregacion de la materia en estudiantes de nivel elemental =

NASA Astrophysics Data System (ADS)

Rosado Olivieri, Wilda Y.

Gran parte de la investigacion acerca de la ensenanza de las ciencias se dedica a estudiar la forma o manera en que los estudiantes visualizan los conceptos cientificos. Para Driver (1983) esas ideas o concepciones se conocen como concepciones alternativas; las cuales pueden ocasionar dificultad para comprender los conceptos de las diferentes areas del conocimiento. El proposito de este estudio fue: (a) indagar como las distintas etapas del ABP permiten explorar las concepciones alternativas que poseen los estudiantes de nivel elemental acerca de los estados de agregacion de la materia y, (b) explorar en que medida el ABP permite identificar e incorporar las concepciones alternativas que poseen los estudiantes de nivel elemental con relacion al concepto de estados de agregacion de la materia para facilitar su aprendizaje. Con el fin de explorar las concepciones alternativas en el tema de los estados agregados de la materia se implanto la estrategia de Aprendizaje Basado en Problemas (ABP) con estudiantes de quinto grado de nivel elemental. Se utilizo la metodologia mixta con varias estrategias de recopilacion de datos, como una pre y pos prueba para elucidar el conocimiento previo y al mismo tiempo las concepciones alternativas sobre el tema bajo estudio y luego verificar el aprendizaje en los estudiantes. Asimismo, el uso de mapas conceptuales para determinar la profundidad del tema estudiado y el entrelazamiento de los conceptos Una tercera estrategia fue el grupo focal para tomar en cuenta la impresion de los estudiantes acerca del proyecto ABP. El aspecto colaborativo y cooperativo fue un factor fundamental, ya que el aprendizaje ocurrio en ese contexto educativo. Para los hallazgos de esta investigacion fue tan importante el conocimiento previo como los procesos que se generaban para que la adquisicion del mismo fuera de forma significativa y funcional (Escribano & Del Valle, 2010). La estrategia de ABP constituyo en este estudio una forma para indagar las concepciones alternativas que poseian los estudiantes y a su vez, determinar como el estudiante manejaba dichas concepciones a situaciones que requeririan aplicar su conocimiento para luego modificar las estructuras conceptuales hacia el conocimiento cientifico.

Resultados do desenvolvimento de um propulsor à plasma no Brasil

NASA Astrophysics Data System (ADS)

Ferreira, I. S.; Ferreira, J. L.

2003-08-01

Uma das partes mais importantes de um satélite é o controle de atitude do mesmo. E se tratando de um satélite científico, a atenção para este sistema deve ser redobrada. Uma possibilidade atraente para executar esta tarefa é a propulsão elétrica. Aqui, mostraremos resultados obtidos pelo propulsor à plasma PHALL-01, desenvolvido na Universidade de Brasília entre 2000 e 2003. Este é derivado do propulsor russo SPT-100 (Stationary Plasma Thruster), mas com o emprego inovador de um arranjo de imãs permanentes como fonte do campo magnético, este último o agente da aceleração do plasma. Esta alteração foi motivada pelo objetivo de que o mesmo operasse com o mínimo de potência elétrica. A partir da formulação teórica do mecanismo de aceleração, tendo como base as equações da magnetohidrodinâmica, pode-se obter vínculos sob os quais o propulsor pudesse ser construído. O mais forte destes é o que dita a topologia do campo magnético. Sendo assim, foram realizadas simulações computacionais, que definiram a geometria do propulsor. Após construído, este foi diagnosticado usando-se sondas de Langmuir e analisadores de energia. Como resultados, obtivemos a distribuição espacial da temperatura, densidade e potencial do plasma, bem como a distribuição angular do feixe produzido pelo mesmo em vários regimes de operação. O espectro de energia do feixe de plasma também foi medido, indicando íons de até 560eV. Combinando estes resultados, calculou-se o empuxo do propulsor: 84mN; e o impulso específico: 1083s. Estes demonstram que o mesmo estará qualificado, num futuro próximo, para o emprego no controle de atitude de satélites científicos, ou até mesmo como parte do conjunto propulsor primário, responsáveis pela transferência de órbitas.

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

NASA Astrophysics Data System (ADS)

Cordova-Santiago, Lizzette Astrid

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

Comprension de los conceptos de los enlaces ionico y covalente en estudiantes universitarios del primer curso de quimica general

NASA Astrophysics Data System (ADS)

Ballesteros Benavides, Maria Elvira

Para este trabajo utilizamos el estudio de casos cualitativo que se llevo a cabo en una universidad privada de Puerto Rico. Empleamos como unidad de analisis el concepto de enlace quimico, ionico y covalente. Los participantes fueron los estudiantes de la seccion nocturna del curso de Quimica General I. La investigacion se desarrollo por medio de dos entrevistas de persona a persona, observaciones de las expresiones no verbales y la hoja de identificacion de conceptos. Para la triangulacion tomamos en consideracion las preconcepciones erroneas, las concepciones alternativas y el mapa de conceptos de cada participante. Preparamos un mapa de conceptos para el enlace quimico validado por un comite de expertos. Tambien, elaboramos los mapas de conceptos de los participantes que sirvieron para varios propositos: conocer la estructura conceptual, expresar los logros, hacer comparaciones e identificar la presencia de concepciones alternativas. Entre los hallazgos encontramos que todos los participantes poseen conocimiento previo de los enlaces quimicos ionico y covalente y dentro de ese conocimiento existen preconcepciones erroneas mas numerosas para el enlace ionico. Al principio del semestre el 50% de los participantes demostraron tener "carencia fuerte de conceptos" tanto para el enlace ionico como para el covalente. Al finalizar el semestre encontramos en el 40% de los participantes concepciones alternativas tanto para el enlace ionico como para el covalente y el 90% no lograron distinguir un enlace del otro. Nuestras conclusiones fueron que los participantes sin distincion del aprovechamiento academico demostraron tener la tendencia de "carencia fuerte de conceptos" tanto para el enlace ionico como para el covalente, presentaron dificultad al integrar los conceptos de los enlaces quimicos ionico y covalente que se pusieron de manifiesto al dar los ejemplos. Las preconcepciones erroneas contribuyen en el desarrollo de las concepciones alternativas. Ademas, los participantes no lograron diferenciar los dos enlaces quimicos. Esto implica que reflexionemos sobre la necesidad de revisar tanto las competencias cognoscitivas como la forma de ensenar quimica en el salon de clase. Recomendamos indagar y dar importancia al conocimiento previo de los estudiantes, enfatizar la ensenanza de los conceptos y propiciar el aprendizaje con significado.

Prevalence of Diphyllobothrium latum (Cestoda: Diphyllobothriidae) plerocercoids in fish species from four Italian lakes and risk for the consumers.

PubMed

Gustinelli, Andrea; Menconi, Vasco; Prearo, Marino; Caffara, Monica; Righetti, Marzia; Scanzio, Tommaso; Raglio, Annibale; Fioravanti, Maria Letizia

2016-10-17

In recent years there has been a re-emergence of diphyllobothriasis by Diphyllobothrium latum (Cestoda: Diphyllobothriidae) in Italy, France and Switzerland, where in the past this fish-borne zoonosis was widespread and then virtually disappeared. A change in eating habits such as the consumption of raw/undercooked freshwater fish, has led to an increased risk for consumers of ingesting infective larvae of D. latum. A survey on the factors responsible for the re-emergence of human diphyllobothriasis in Italy was carried out from March 2013 to December 2014. The aim of this study was to assess the diffusion of D. latum plerocercoids in the fish populations of the sub-alpine lakes of Maggiore, Como, Iseo and Garda, updating the scarce historical data and assessing a preliminary "risk level" of the lacustrine environments and fish species under investigation. A total of 2228 fish belonging to 5 species, 690 from Lake Maggiore, 500 from Lake Como, 655 from Lake Iseo and 383 from Lake Garda were submitted to parasitological examination. The presence of D. latum plerocercoid larvae was detected in 6.6%, 25.4% and 7.6% of perch (Perca fluviatilis) from Lakes Maggiore, Como and Iseo respectively. The parasite was also present in pike (Esox lucius) with prevalence values ranging from 71.4 to 84.2% and in 3.6-3.8% of burbot (Lota lota) from Lakes Iseo and Como. Fish from Lake Garda were negative as well as sampled whitefish (Coregonus lavaretus) and shad (Alosa fallax lacustris). The results of this survey showed a widespread presence of D. latum plerocercoid larvae in Maggiore, Como and Iseo fish populations. Urban fecal contamination of water is still a key issue to be resolved, together with the improvement of communication with consumers regarding the best dietary habits and the most effective processes of parasite inactivation, required for the consumption of raw/undercooked fish caught in high-risk areas. Copyright © 2016 Elsevier B.V. All rights reserved.

Análise sobre o Conhecimento de um Grupo de Alunos do Ensino Médio da Rede Estadual de São Paulo sobre Termos e Fenômenos Astronômicos do Cotidiano

NASA Astrophysics Data System (ADS)

de Oliveira, E. F.; Voelzke, M. R.; Amaral, L. H.

2007-08-01

Embora os Parâmetros Curriculares Nacionais do Ensino Médio (PCN-EM) e as orientações complementares a esses Parâmetros (PCN+) apontem a importância de uma abordagem significativa de conceitos relacionados à astronomia nas aulas de Física, muitos estudantes terminam o Ensino Médio (EM) sem compreender a razão de certos acontecimentos de origem celeste, ainda que estes façam parte de seu cotidiano. Este trabalho tem por objetivo analisar os conhecimentos básicos em astronomia dos alunos de EM da escola estadual Batista Renzi, bem como investigar os meios através dos quais estes conhecimentos foram adquiridos. Para tanto foi elaborado um questionário de múltipla escolha aplicado a 310 alunos distribuídos entre as três séries do EM dos períodos matutino e noturno. Dessa forma, observou-se que apenas 34,5% relacionaram as estações do ano à inclinação do eixo de rotação da Terra, 21,3% indicaram a influência gravitacional da Lua e do Sol como responsáveis pelo fenômeno das marés, 24,5% indicaram corretamente quais são os objetos celestes mais próximos da Terra, 36,1% identificaram ano-luz como uma medida de distância e 34,2% reconheceram uma estrela cadente como meteoro. Em contrapartida, 67,1% compreendiam a sucessão entre dia e noite, 73,9% identificaram o Sol como estrela e 52,3% relacionaram o Big Bang à origem do Universo. Além disso, foram comparadas as respostas de alunos de diferentes séries e períodos, observando-se, dentre outras coisas, que os estudantes do terceiro ano apresentam um percentual de acertos semelhante ao dos alunos do primeiro, caracterizando que a abordagem de tópicos relacionados à astronomia no EM não tem contribuído para uma maior compreensão dos fenômenos e conceitos.

Determinação de regiões de órbitas diretas estáveis ao redor da Lua

NASA Astrophysics Data System (ADS)

de Melo, C. F.; Winter, O. C.; Vieira Neto, E.

2003-08-01

Neste Trabalho estamos investigando regiões do sistema Terra-Lua que contêm órbitas diretas estáveis ao redor da Lua visando a utilização destas órbitas em futuras missões de veículos espaciais como alternativas de trajetórias com baixo custo de manutenção. Adotando-se o problema restrito de três corpos, Terra-Lua-partícula, a localização e a extensão destas regiões de estabilidade foram investigadas numericamente considerando como estável toda órbita que permanece ao redor a Lua por, no mínimo, 1000 dias com energia de dois corpos da partícula em relação à Lua negativa. A estabilidade de tais regiões está associada a duas famílias de órbitas periódicas simples H1 e H2 e a órbitas quase-periódicas associadas a elas. Uma vez identificadas as regiões de estabilidade passamos a analisá-las introduzindo, paulatinamente, outras interações relevantes ao sistema como as perturbações do Sol (via problema restrito de quatro corpos), das marés, da pressão de radiação e do achatamento terrestre. Os resultados encontrados até o momento mostram que a perturbação do Sol é a única que reduz significativamente o tamanho das regiões de estabilidade. Também estamos investigando o comportamento de tais regiões quando características intrínsecas do sistema como as excentricidades das órbitas da Terra e da Lua e a inclinação da órbita Lua são consideradas. Com este estudo estamos reunindo informações que nos permitirão compreender a evolução das regiões de estabilidade no sistema Terra-Lua, bem como estabelecer parâmetros adequados para a utilização das trajetórias estáveis em futuras missões espaciais. Agradecimentos: Este projeto conta com o apoio do CNPq, da Capes e da Fapesp.

Infant mortality by color or race from Rondônia, Brazilian Amazon.

PubMed

Gava, Caroline; Cardoso, Andrey Moreira; Basta, Paulo Cesar

2017-04-10

To analyze the quality of records for live births and infant deaths and to estimate the infant mortality rate for skin color or race, in order to explore possible racial inequalities in health. Descriptive study that analyzed the quality of records of the Live Births Information System and Mortality Information System in Rondônia, Brazilian Amazonian, between 2006-2009. The infant mortality rates were estimated for skin color or race with the direct method and corrected by: (1) proportional distribution of deaths with missing data related to skin color or race; and (2) application of correction factors. We also calculated proportional mortality by causes and age groups. The capture of live births and deaths improved in relation to 2006-2007, which required lower correction factors to estimate infant mortality rate. The risk of death of indigenous infant (31.3/1,000 live births) was higher than that noted for the other skin color or race groups, exceeding by 60% the infant mortality rate in Rondônia (19.9/1,000 live births). Black children had the highest neonatal infant mortality rate, while the indigenous had the highest post-neonatal infant mortality rate. Among the indigenous deaths, 15.2% were due to ill-defined causes, while the other groups did not exceed 5.4%. The proportional infant mortality due to infectious and parasitic diseases was higher among indigenous children (12.1%), while among black children it occurred due to external causes (8.7%). Expressive inequalities in infant mortality were noted between skin color or race categories, more unfavorable for indigenous infants. Correction factors proposed in the literature lack to consider differences in underreporting of deaths for skin color or race. The specific correction among the color or race categories would likely result in exacerbation of the observed inequalities. Analisar a qualidade dos registros de nascidos vivos e de óbitos infantis e estimar a taxa de mortalidade infantil segundo cor ou raça, a fim de explorar iniquidades étnico-raciais em saúde. Estudo descritivo que analisou a qualidade dos registros do Sistema de Informações sobre Nascidos Vivos e do Sistema de Informações sobre Mortalidade em Rondônia, Amazônia brasileira, entre 2006-2009. As taxas de mortalidade infantil foram estimadas nas categorias de cor ou raça, pelo método direto, e corrigidas por: (1) distribuição proporcional dos óbitos com cor ou raça ignorada; e (2) aplicação de fatores de correção. Efetuou-se também o cálculo da mortalidade proporcional por causas e grupos etários. Entre 2008-2009, a captação de nascimentos e óbitos melhorou em relação aos anos de 2006-2007, requerendo fatores de correção menores para estimar a taxa de mortalidade infantil. O risco de morte de crianças indígenas (31,3/1.000 nascidos vivos) foi maior que o registrado nos demais grupos de cor ou raça, excedendo em 60% a mortalidade infantil média no estado (19,9/1.000 nascidos vivos). As crianças pretas apresentaram as maiores taxas de mortalidade infantil neonatal, enquanto as indígenas apresentaram as maiores taxas de mortalidade infantil pós-neonatal. Observou-se que 15,2% dos óbitos indígenas foram por causas mal definidas, enquanto nos demais grupos não ultrapassaram 5,4%. A mortalidade infantil proporcional por doenças infecciosas e parasitárias foi maior entre indígenas, ao passo que entre crianças pretas, sobressaíram as causas externas (8,7%). Observaram-se expressivas iniquidades na mortalidade infantil entre as categorias de cor ou raça, com situação mais desfavorável às crianças indígenas. Os fatores de correção propostos na literatura não consideram diferenças na subenumeração de óbitos entre as categorias de cor ou raça. A correção específica entre as categorias de cor ou raça provavelmente resultaria em exacerbação das iniquidades observadas.

Life Course Experiences, Pain and Suffering: A Case Study of an Older Mexican American Woman with Mobility Impairment

PubMed Central

Walker, Janiece L.; Harrison, Tracie C.; Hendrickson, Sherry G.

2012-01-01

There is a dearth of literature examining how adversity shapes the experiences of pain and/or suffering in a middle aged Mexican American women. The purpose of this qualitative descriptive study was to understand pain and suffering from a life course perspective as described by a Mexican American woman aging with early onset mobility impairment. This Hispanic woman experienced episodes of abuse and rejection over the life course, which may have significantly influenced her pain and suffering experience in adulthood. This adds to the literature on how adversity influences later life pain experience and provides insight on why pharmacological treatment alone may not be as successful as a holistic intervention. Hay escasez de literatura que examine cómo la adversidad da forma a las experiencias de dolor y / o sufrimiento en mujeres mexicana-americana mayores de edad. El propósito de este estudio descriptivo cualitativo fue comprender el dolor y el sufrimiento desde una perspectiva de ciclo de vida como descrito por una mujer mexicana-americana envejeciendo con inicio temprano de deterioro de movilidad. Esta Latina experimentó episodios de maltrato y rechazo, que se percibió haber afectado su experiencia de dolor y sufrimiento luego como adulta. Este estudio aumenta la literatura sobre cómo la adversidad influya la experiencia de dolor más tarde en la vida, y nos permite comprender mejor como el tratamiento farmacológico por sí solo no es tan exitoso como pueda ser una intervención integral. PMID:24830728

[Not Available].

PubMed

Domínguez, Raúl; Garnacho-Castaño, Manuel Vicente; Maté-Muñoz, José Luis

2016-06-30

La fuerza influye directamente en el estado de salud y en la capacidad de fitness, motivo por el que el entrenamiento contra resistencias o resistance training (RT) se incluye dentro de aquellos programas de ejercicio encaminados a mejorar la salud y calidad de vida. Debido a que muchasenfermedades cursan con alteración de la masa y funcionalidad muscular y a que el RT es la principal modalidad de ejercicio encaminada a mejorar la función muscular, el objetivo de la presente revisión bibliográfica ha sido exponer las evidencias actuales sobre las adaptaciones delRT, así como su posible aplicación en patologías como la obesidad, diabetes, dislipemia, hipertensión, cáncer, Parkinson, esclerosis múltiple o fibromialgia. El RT en estas enfermedades puede aumentar los niveles de masa muscular, disminuyendo los niveles de masa grasa, los nivelesde ácidos grasos en sangre y la glucemia, incrementando la sensibilidad a la insulina, y disminuyendo los niveles de citokinas inflamatorias. El RT, además, mejora el gasto cardiaco y la funcionalidad endotelial, regulando la tensión arterial e incrementando el consumo de oxígeno. Las ganancias de fuerza muscular mejoran la funcionalidad y la calidad de vida, especialmente en población con una afectación neuromuscular grave, como pudieran ser los enfermos de esclerosis múltiple, fibromialgia o Parkinson. Por ello, el RT debe ser incorporado como parte del tratamiento en las personas que presentan determinado tipo de patologías.

Valorisation of Como Historical Cadastral Maps Through Modern Web Geoservices

NASA Astrophysics Data System (ADS)

Brovelli, M. A.; Minghini, M.; Zamboni, G.

2012-07-01

Cartographic cultural heritage preserved in worldwide archives is often stored in the original paper version only, thus restricting both the chances of utilization and the range of possible users. The Web C.A.R.T.E. system addressed this issue with regard to the precious cadastral maps preserved at the State Archive of Como. Aim of the project was to improve the visibility and accessibility of this heritage using the latest free and open source tools for processing, cataloguing and web publishing the maps. The resulting architecture should therefore assist the State Archive of Como in managing its cartographic contents. After a pre-processing consisting of digitization and georeferencing steps, maps were provided with metadata, compiled according to the current Italian standards and managed through an ad hoc version of the GeoNetwork Opensource geocatalog software. A dedicated MapFish-based webGIS client, with an optimized version also for mobile platforms, was built for maps publication and 2D navigation. A module for 3D visualization of cadastral maps was finally developed using the NASA World Wind Virtual Globe. Thanks to a temporal slidebar, time was also included in the system producing a 4D Graphical User Interface. The overall architecture was totally built with free and open source software and allows a direct and intuitive consultation of historical maps. Besides the notable advantage of keeping original paper maps intact, the system greatly simplifies the work of the State Archive of Como common users and together widens the same range of users thanks to the modernization of map consultation tools.

Percepción de competencia y adiestramiento profesional especializado relativos al VIH/SIDA en estudiantes y profesionales de la salud: el estigma como un indicador de necesidad

PubMed Central

RODRÍGUEZ, Yarimar ROSA; DÍAZ, Nelson VARAS

2009-01-01

El proceso de estigmatización asume una devaluación de la persona debido a una característica o marca que haya sido identificada socialmente y que permita que se le describa como diferente. Desde que se desató la epidemia del VIH/SIDA, vivir con la enfermedad ha sido señalado de manera social como una marca estigmatizante. Las manifestaciones de dicha estigmatización se han documentado entre profesionales de la salud. Este estigma puede afectar los servicios de salud que las personas que viven con VIH/SIDA reciben de estos profesionales. Los objetivos de esta investigación fueron explorar: 1) la percepción que tienen estudiantes y profesionales de la salud sobre su nivel de competencia para ofrecer servicios a personas que viven con VIH/SIDA, 2) las opiniones de éstos sobre el tipo de adiestramiento profesional recibido y la necesidad del mismo, y 3) la manifestación de actitudes estigmatizantes como indicadores de necesidad de adiestramiento profesional. La muestra total del estudio estuvo compuesta por 80 de diversas profesiones de la salud. Los resultados reflejan que algunos/as de los/as participantes han recibido formación en VIH pero ésta no ha sido suficiente para contrarrestar las nociones estigmatizantes. Discutimos las implicaciones de los resultados para investigaciones futuras y el desarrollo de intervenciones con vías de minimizar las nociones estigmatizantes en los escenarios de salud. PMID:20011236

Alejarse como proceso social: niños y ancianos «abandonados» en Ayacucho1

PubMed Central

Leinaweaver, Jessaca

2013-01-01

En investigaciones previas sobre el acogimiento familiar y la adopción en Ayacucho, se ha podido descubrir cómo los ayacuchanos adquieren y producen relaciones sociales. Mientras negocian creativamente los discursos y espacios construidos simultáneamente por instituciones, comunidades, y estructuras sociales, van adquiriendo nuevas formas de relacionarse. Este artículo discute el proceso opuesto: el deshacerse de relaciones de parentesco, y el proceso social del abandono o alejamiento. Cuando se aleja a una persona de su familia o su comunidad, los que se quedan en ella llegan a entenderse como ciertos tipos de personas. En los estudios de caso discutidos aquí, recopilados a través de una detallada y cuidadosa observación participante y de entrevistas etnográficas grabadas entre 2001 y 2007, se puede ver cómo, después de un alejamiento social, los individuos que alejan se reinterpretan como sujetos que se encuentran superándose o volviéndose modernos, o bien sacrificándose. PMID:25177044

Cálculos ab initio con correlación electrónica

NASA Astrophysics Data System (ADS)

Merchán Bonete, M.

Estamos entrando en una era donde la ortogonalidad entre las investigaciones de carácter experimental y de naturaleza teórica se irá difuminando progresivamente y la problemática a resolver quedará en escena como el único actor principal de la obra. Como premisa para una cooperación teórico-experimental de igual a igual, la metodología químico-cuántica utilizada debe ser capaz de ofrecer resultados de carácter predictivo. Sin duda, esta madurez en la metodología químico-cuántica ya la hemos alcanzado hace algunos años, tal y como muestra entre otras muchas, la labor que nuestro grupo ha realizado en el transcurso de la última década, dentro del campo de la Espectroscopía Teórica. Los estudios realizados comprenden una amplia gama de sistemas, variando tanto en tamaño como en complejidad, abordando problemáticas espectroscópicas consideradas tradicionalmente como especialmente controvertidas. Nuestra contribución científica más relevante reside en el carácter cuantitativo de las asignaciones espectroscópicas que hemos propuesto en base a resultados ab initio. Recordemos que en los años noventa los resultados ab initio solían presentar para las energías de excitación de sistemas de tamaño molecular moderado, como el benceno, errores de más de 1 eV. En comparación con el éxito relativo de los métodos semiempíricos, la frustración de la metodología ab initio quedaba todavía más patente. Los estudios que hemos presentado representan una comprensión profunda de los espectros electrónicos en sistemas orgánicos claves, mostrando el camino a seguir para obtener asignaciones espectroscópicas precisas (entre 0.1-0.2 eV). La naturaleza del método CASPT2 junto al diseño de estrategias computacionales nos ha permitido alcanzar el carácter cuantitativo con el que se caracterizan nuestras contribuciones[1,2]. Por todo ello, algunos de los trabajos publicados se consideran clásicos dentro del campo, pues en cierto modo definen el campo, y se reflejan en libros publicados recientemente. En la conferencia se analizarán ciertos pormenores de las investigaciones realizadas. El tipo de aplicaciones llevadas a cabo hasta la fecha se ilustrará mediante el estudio teórico del espectro electrónico de ciclooctatetraeno. Dando un paso más en la evolución de nuestra investigación, pretendemos en la actualidad describir, desde un formalismo teórico y al mismo nivel de exigencia, los mecanismos subyacentes que tienen lugar en las reacciones biológicas fototoinducidas, es decir, reacciones que se inician mediante la absorción de luz[3]. Como muestra de la caracterización de los procesos fotofísicos y fotoquímicos en fotobiología teórica, hemos elegido la descripción de la conversión interna ultrarrápida que tiene lugar en los cromóforos del ADN. Los estados excitados de las moléculas de los ácidos nucleicos presentan tiempos de vida media que se encuentran en el rango de sub-picosegundos, sugiriendo la presencia de un canal ultrarrápido de conversión interna, lo que normalmente se asocia en la fotoquímica contemporánea a una intersección cónica entre el estado excitado y el fundamental[4]. De esta forma nuestro ADN previene de forma eficaz posibles reacciones en el estado excitado y se revela como un excelente protector solar.

Astronomy in High School: Using a Mini-Planetarium to Understand Details of the Apparent Movement of Stars. (Spanish Title: Astronomía en la Escuela Secundaria: Comprendiendo los Detalles del Movimiento Aparente de Las Estrellas con un Miniplanetario.) Astronomia no Ensino Médio: Compreendendo Detalhes do Movimento Aparente das Estrelas com um Miniplanetário

NASA Astrophysics Data System (ADS)

dos Santos Leão, Demetrius

2013-07-01

The aim of this article is to present part of the results obtained by the intervention made from the author's Master degree project, which consisted in the development of a set of Astronomy classes for first year of High School students from a private school in the "Distrito Federal", Brasilia, Brazil, making use of a didactical material called mini-planetarium (MP) as the main resource. Using Paulo Freire's contextualization and dialogicity ideas as a theoretical framework guided by these lessons, it was proposed to the students the assembly and application of that resource in a planetarium session. During the project, some subjects such as the apparent trajectory of stars through Brasilia's sky, the location of the cardinal points beginning from the Southern Cross constellation, the color of stars and the stars being seen from a particular place were emphasized. It was found that the students showed an improvement of their understanding about these subjects, as well as a significant excitement with the developed methodology. El objetivo de este trabajo es presentar algunos de los resultados obtenidos en el proyecto de la tesis de maestría del autor, que incluyó el desarrollo de algunas clases de Astronomía, con estudiantes del primer año del bachillerato de una escuela privada del Distrito Federal (Brasilia, Brasil), utilizando como materia prima didáctica el recurso llamado miniplanetario (MP). Utilizando como base teórica orientadora de esas clases las ideas de contextualización y dialógica de Paulo Freire, fue propuesto a los estudiantes el montaje y la utilización de este recurso en una función de planetario. Durante el proyecto, se enfatizaron asuntos tales como la trayectoria aparente de las estrellas del cielo de Brasilia, la ubicación de los puntos cardinales a partir de la constelación de la Cruz del Sur, los colores de las estrellas y las estrellas vistas desde una localidad determinada. Se constató que los estudiantes mostraron una mejora en la comprensión de estas cuestiones y demostraron un gran interés por esta metodología. O objetivo deste artigo é apresentar parte dos resultados obtidos com a intervenção feita como projeto da dissertação de mestrado do autor, que consistiu no desenvolvimento de um conjunto de aulas de Astronomia, com alunos do 1º Ano do Ensino Médio de uma escola da rede privada do Distrito Federal (Brasília, Brasil), empregando como recurso principal um material didático chamado miniplanetário (MP). Utilizando como pressuposto teórico norteador dessas aulas as ideias de contextualização e dialogicidade de Paulo Freire, foi proposta aos estudantes a montagem e utilização desse recurso em uma sessão de planetário. Durante o projeto, enfatizaram-se assuntos como a trajetória aparente das estrelas para o céu de Brasília, a localização dos pontos cardeais a partir da constelação do Cruzeiro do Sul, as cores das estrelas e as estrelas vistas de uma determinada localidade. Apurou-se que os alunos apresentaram melhoria na compreensão desses assuntos, bem como demonstraram expressiva empolgação com essa metodologia desenvolvida.

Reproductive success of Macrotermes bellicosus (Isoptera, Macrotermitinae) in two neighbouring habitats.

PubMed

Korb, Judith; Linsenmair, Karl Eduard

1999-02-01

The fungus-cultivating, mound-building termite Macrotermes bellicosus can reach high densities in African savannah habitats, whereas in forests it is comparatively rare and is only found in relatively open areas. Earlier studies in the Comoé National Park (Côte d'Ivoire, West Africa) suggested that this might be because ambient temperatures are lower in the forest than the savannah. Therefore, forests seem to be suboptimal habitats. During 3 consecutive years we measured relevant fitness parameters in both habitats to test this hypothesis. Colonies in the savannah had higher reproductive outputs. They reproduced annually, producing high numbers of offspring (alates), whereas forest colonies reproduced on average only once every 3 years and even then only low numbers of alates were produced. Annual growth of mound height, which can be regarded as an indicator of colony growth, varied considerably between individual colonies and years. Nevertheless, in two years the growth rate of mounds in the shrub savannah was higher than that of mounds in the gallery forest. Unexpectedly, survival probability as calculated by Kaplan Meier analysis was much lower for colonies in the shrub savannah than for colonies in the gallery forest. Using these data in a computer simulation we calculated lifetime reproductive success (LRS) for an average colony in both habitats. As LRS was much higher for colonies in the shrub savannah than in the gallery forest, these results confirmed our suggestion that the forest is a suboptimal habitat for M. bellicosus.

Characterization of Deactivated Bio-oil Hydrotreating Catalysts

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

Wang, Huamin; Wang, Yong

Deactivation of bio-oil hydrotreating catalysts remains a significant challenge because of the poor quality of pyrolysis bio-oil input for hydrotreating and understanding their deactivation mode is critical to developing improved catalysts and processes. In this research, we developed an understanding of the deactivation of two-step bio-oil hydrotreating catalysts (sulfided Ru/C and sulfided CoMo/C) through detailed characterization of the catalysts using various complimentary analytical techniques. Severe fouling of both catalysts by carbonaceous species was the major form of deactivation, which is consistent with the significant loss of surface area and pore volume of both deactivated catalysts and the significant increase ofmore » the bulk density. Further analysis of the carbonaceous species by thermogravimetric analysis and x-ray photoelectron spectroscopy indicated that the carbonaceous species was formed by condensation reaction of active species such as sugars and sugar derivatives (aldehydes and ketones) in bio-oil feedstock during bio-oil hydrotreating under the conditions and catalysts used. Microscopy results did not show metal sintering of the Ru/C catalyst. However, X-ray diffraction indicated a probable transformation of the highly-active CoMoS phase in the sulfided CoMo/C catalyst to Co8S9 and MoS2 phase with low activity. Loss of the active site by transport of inorganic elements from the bio-oil and the reactor construction material onto the catalyst surface also might be a cause of deactivation as indicated by elemental analysis of spent catalysts.« less

Lactancia Materna y VIH/SIDA

PubMed Central

Valeria Cortés, F.; Jaime Pérez, A.; Lilian Ferrer, L.; Rosina Cianelli, A.; Báltica Cabieses, V.

2009-01-01

Resumen VIH/SIDA es una pandemia que afecta a hombres, mujeres y niños, pero que presenta una tendencia hacia la feminización, afectando especialmente a mujeres jóvenes. Su consecuencia es el aumento de la transmisión vertical, durante el embarazo, parto o lactancia materna. Este estudio bibliográfico describe la relación entre VIH/SIDA y lactancia materna, explicitando factores que influyen en la elección de la modalidad de alimentación de madres viviendo con VIH/SIDA. Se describen causas de morbimortalidad infantil asociada y recomendaciones internacionales de lactancia en mujeres con VIH/SIDA. En un mundo globalizado con constantes migraciones poblacionales, estos resultados representan un llamado de atención para profesionales de salud quienes deben considerar factores sociales que influenciarán la toma de decisión de madres viviendo con VIH/SIDA al escoger la modalidad de lactancia. No sólo basta conocer el riesgo de transmisión vertical, sino que se debe tomar conciencia de aquellos factores dinámicos y específicos de cada comunidad. PMID:20046815

The Douro estuarine plume: Detection, processes and dynamics =

NASA Astrophysics Data System (ADS)

Mendes, Renato Paulo dos Santos

O Douro e um dos maiores rios da Peninsula Iberica, constituindo a maior descarga de agua doce para o Oceano Atlântico na costa noroeste portuguesa. A sua pluma estuarina tem particular relevância na dinâmica costeira e na modulacao de fenomenos biogeoquimicos. Sao objetivos desta dissertacao contribuir para a compreensao dos processos fisicos associados a geracao e propagacao da pluma estuarina do Rio Douro no oceano, assim como para o conhecimento dos seus padroes de dispersao e da forma como estes alteram a hidrologia e a circulacao costeira, considerando os agentes forcadores tipicos deste fenomeno (caudal fluvial, vento e mare) e indices climaticos relevantes. Para concretizacao destes objetivos foram desenvolvidas e aplicadas metodologias inovadoras de processamento de dados de detecao remota, assim como novas implementacoes estuarinas e costeiras de modelos numericos. Atraves de imagens MODIS, otimizadas para o estudo de fenomenos costeiros, efetuou-se uma detecao rigorosa da pluma. Identificou-se uma relacao entre o sinal turbido nLw555 e o caudal, demonstrando-se este produto como um bom proxy para a observacao da pluma no oceano. As escalas temporais e espaciais da pluma foram caraterizadas atraves destas imagens, combinadas com dados de caudal fluvial, mare, vento e precipitacao, e tambem com indices climaticos relevantes. Para compreender a propagacao da pluma e caracterizar a sua dinâmica e impacto na circulacao costeira, foi desenvolvida uma aplicacao 3D de modelos estuarinos e costeiros com malhas aninhadas de resolucao variavel. Definiramse e analisaram-se diferentes cenarios de vento e descarga fluvial. A interacao da pluma do Rio Douro e do Minho foi ainda analisada atraves dos resultados de simulacoes baseadas num evento de inverno. Os compositos turbidos mostraram que a pluma e facilmente detetada quando o caudal e maior que 500 m3 s??1. A descarga fluvial e o vento sao os principais forcadores da sua propagacao, enquanto a mare e apenas importante na regiao proxima a embocadura do estuario. Observaram-se relacoes a uma escala interanual entre a turbidez da pluma e os indices climaticos East Atlantic e NAO, com uma correlacao maxima identificada com 1 e 3 meses de desfasamento, respetivamente. Com base nos resultados das simulacoes efetuadas, a pluma e classificada como de larga escala e de advecao superficial, apresentando caracteristicas de uma pluma prototipica. Em condicoes de caudal moderado a elevado, a descarga estuarina e suficiente para gerar uma corrente costeira para norte sem acao do vento. Em eventos de ventos leste, a propagacao da pluma e similar ao caso sem vento, com um aumento da velocidade da corrente. Uma corrente costeira para sul e unicamente identificada sob condicoes de forte vento de oeste. Ventos de norte tendem a estender a pluma para o largo, com uma inclinacao na direcao sudoeste, enquanto ventos de sul intensificam a corrente para norte, sendo a mistura das plumas do Douro e do Minho uma consequencia possivel. A analise desta interacao apontou a contribuicao do Douro como importante na estabilizacao da WIBP e nas trocas de agua entre o oceano e as Rias Baixas. A interacao da pluma do Douro com estuarios localizados a sul da sua foz e a confirmacao in situ da recirculacao observada nos resultados numericos afiguram-se como temas relevantes para investigacoes futuras. None

Patient safety and nursing: interface with stress and Burnout Syndrome.

PubMed

Rodrigues, Cláudia Cristiane Filgueira Martins; Santos, Viviane Euzébia Pereira; Sousa, Paulo

2017-01-01

To analyze studies on stress, Burnout Syndrome, and patient safety in the scope of nursing care in the hospital environment. This was an integrative literature review. Data collection was performed in February 2016 in the following databases: Medical Literature Analysis and Retrieval System Online - PubMed/MEDLINE, Latin American and Caribbean Literature in Health Sciences - LILACS. Ten scientific productions were selected, which listed that factors contributing to stress and Burnout Syndrome of nursing professionals are the work environment as a source of stress, and excessive workload as a source of failures. The analysis found that the stress and Burnout Syndrome experienced by these professionals lead to greater vulnerability and development of unsafe care, and factors such as lack of organizational support can contribute to prevent these failures. Analisar estudos que versam sobre o estresse e Síndrome de Burnout, bem como a segurança do paciente no âmbito da assistência de enfermagem no ambiente hospitalar. Tratou-se de uma revisão integrativa de literatura. O levantamento dos dados foi efetuado nas bases de dados Medical Literature Analysis and Retrieval System Online - PubMed / MEDLINE, Literatura Latino-Americana e do Caribe em Ciências da Saúde -LILACS em fevereiro de 2016. Foram selecionadas10 produções científicas que apontaram que os fatores que contribuem para o estresse e a Síndrome de Burnout dos profissionais de enfermagem são o ambiente de trabalho como fonte de estresse e a carga de trabalho excessiva como geradora de falhas. A análise apontou que o estresse e a Síndrome de Burnout vivenciada por esses profissionais acarretam maior vulnerabilidade ao desenvolvimento de uma assistência insegura e que fatores como a falta de apoio organizacional podem contribuir para dirimir essas falhas.

XAS Study at Mo and Co K-Edges of the Sulfidation of a CoMo / Al2O3 Hydrotreating Catalyst

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

Pichon, C.; Gandubert, A. D.; Legens, C.

2007-02-02

Because of its impact on environment, the removal of sulfur is an indispensable step, called hydrotreatment, in the refining of petroleum. One of the most commonly used hydrotreating catalysts is CoMo-type catalyst which is composed of molybdenum disulfide slabs promoted by cobalt atoms (CoMoS phase) and well dispersed on a high specific area alumina. As far as the highest sulfur content allowed in gasoline and diesel is continually decreasing, more and more efficient and active hydrotreating catalysts are required. In order to optimize the reactivity of the CoMo-type catalyst in hydrotreatment, a better understanding of the processes used to producemore » the active phase (CoMoS slabs) of the catalyst is necessary. The study reported here deals with the sulfiding mechanism of the slabs and the influence of temperature on the phenomenon. Ex situ X-ray absorption spectroscopy (XANES and EXAFS) was used to study the evolution of the structure of CoMo-type catalyst sulfided at various temperatures (from 293 to 873 K). XAS analysis was performed at both molybdenum and cobalt K-edges to obtain a cross-characterization of the sulfidation of the slabs. It evidenced the formation of various compounds, including two molybdenum oxides, MoS3 (or MoS3-like compound) and Co9S8, at specific steps of the sulfiding process. It showed the role of intermediate played by MoS3 (or MoS3-like compound) during the formation of the slabs and the competition between the appearance of promoted slabs (CoMoS phase) and Co9S8. At last, it leaded to the proposal of a mechanism for the sulfidation of the catalyst.« less

Contribution to the scintillation detection optimization in double phase detectors for direct detection of dark matter

NASA Astrophysics Data System (ADS)

Balan, Catalin

Na ultima decada, foram feitos grandes progressos no desenvolvimento dos detetores de detecao direta das particulas que constituem a materia negra. Com estrategias do aumento gradual do volume do alvo e, simultaneamente, de reducao dos niveis de fundo, a experiencia XENON obteve resultados muito bons e perspetivas promissoras para a detecao de materia negra. Tarefas relativas a analise de dados experimentais adquiridos com o detetor de dupla fase em uso, assim como as simulacoes do campo eletrico, desenvolvimento, montagem e testes para o proximo detetor XENON1T, assim como a participacao regular na manutencao geral e monitorizacao do prototipo atual XENON100 no LNGS, constituiram o plano de trabalhos para as atividades de investigacao do presente doutoramento e a minha contribuicao para a otimizacao da detecao de cintilacao nos detetores da experiencia XENON. A necessidade de alcancar niveis elevados de sensibilidade, requer inovacao em todos os aspetos fisicos do detetor, assim como a reducao de todas as fontes de radioatividade que contribuem para o fundo. O modo mais indicado de operacao para os detetores com enchimento a Xe no estado liquido e gasoso envolve a medicao da cintilacao primaria e da secundaria provenientes da interacao das particulas no Xe liquido. A razao entre estes dois sinais permite diferenciar claramente a maior parte dos eventos correspondentes as fundo dos eventos correspondentes a WIMPs. Deste modo, a leitura dos sinais correspondentes a cintilacao e de extrema importancia. A amplitude do sinal de cintilacao antes dos fotossensores e maximizada atraves da otimizacao de varios parametros, tais como a geometria do alvo do detetor, a transparencia das grelhas dos eletrodos, a uniformidade do ganho em cintilacao secundaria e a utilizacao de material reflectivo para cobrir as superficies que nao sao fotossensiveis.

Esquizofrenia y trastorno en el consumo de sustancias: prevalencia y characterísticas sociodemográficas en la población Latina

PubMed Central

Jiménez-Castro, Lorena; Raventós-Vorst, Henriette; Escamilla, Michael

2012-01-01

El interés por comprender la co-morbilidad de la esquizofrenia y el trastorno en el uso de sustancias, ha aumentado debido al incremento de este diagnóstico, a los efectos negativos observados en el sujeto y a los costos en los servicios de salud. Este trastorno dual puede tener efectos dramáticos en el curso clínico del trastorno psicótico tales como: mayores recaídas, re-hospitalizaciones, síntomas más severos, no adherencia al tratamiento antipsicótico, cambios marcados del humor, aumento en el grado de hostilidad e ideación suicida, así como alteraciones en otras áreas del funcionamiento incluyendo violencia, victimización, indigencia y problemas legales. La literatura proveniente en particular de Estados Unidos y Europa sugiere que el rango de prevalencia para este diagnóstico puede oscilar entre el 10% hasta el 70%. En este estudio, revisamos la prevalencia del diagnóstico dual de esquizofrenia y trastorno en el uso sustancias, así como sus características sociodemográficas, con base en la literatura disponible alrededor del mundo dando énfasis en la poblacion latina. A pesar de que este diagnóstico es ampliamente aceptado, se conoce poco sobre su prevalencia en la población latina, sobre los factores ambientales, demográficos, clínicos y otras características de estos individuos. Un mejor conocimiento sobre este diagnóstico permitiría mejorar los métodos para la detección y adecuada valoración del trastorno en el uso de sustancias en personas con trastornos metales severos como la esquizofrenia. PMID:21404151

Economic Choices Reveal Probability Distortion in Macaque Monkeys

PubMed Central

Lak, Armin; Bossaerts, Peter; Schultz, Wolfram

2015-01-01

Economic choices are largely determined by two principal elements, reward value (utility) and probability. Although nonlinear utility functions have been acknowledged for centuries, nonlinear probability weighting (probability distortion) was only recently recognized as a ubiquitous aspect of real-world choice behavior. Even when outcome probabilities are known and acknowledged, human decision makers often overweight low probability outcomes and underweight high probability outcomes. Whereas recent studies measured utility functions and their corresponding neural correlates in monkeys, it is not known whether monkeys distort probability in a manner similar to humans. Therefore, we investigated economic choices in macaque monkeys for evidence of probability distortion. We trained two monkeys to predict reward from probabilistic gambles with constant outcome values (0.5 ml or nothing). The probability of winning was conveyed using explicit visual cues (sector stimuli). Choices between the gambles revealed that the monkeys used the explicit probability information to make meaningful decisions. Using these cues, we measured probability distortion from choices between the gambles and safe rewards. Parametric modeling of the choices revealed classic probability weighting functions with inverted-S shape. Therefore, the animals overweighted low probability rewards and underweighted high probability rewards. Empirical investigation of the behavior verified that the choices were best explained by a combination of nonlinear value and nonlinear probability distortion. Together, these results suggest that probability distortion may reflect evolutionarily preserved neuronal processing. PMID:25698750

Economic choices reveal probability distortion in macaque monkeys.

PubMed

Stauffer, William R; Lak, Armin; Bossaerts, Peter; Schultz, Wolfram

2015-02-18

Economic choices are largely determined by two principal elements, reward value (utility) and probability. Although nonlinear utility functions have been acknowledged for centuries, nonlinear probability weighting (probability distortion) was only recently recognized as a ubiquitous aspect of real-world choice behavior. Even when outcome probabilities are known and acknowledged, human decision makers often overweight low probability outcomes and underweight high probability outcomes. Whereas recent studies measured utility functions and their corresponding neural correlates in monkeys, it is not known whether monkeys distort probability in a manner similar to humans. Therefore, we investigated economic choices in macaque monkeys for evidence of probability distortion. We trained two monkeys to predict reward from probabilistic gambles with constant outcome values (0.5 ml or nothing). The probability of winning was conveyed using explicit visual cues (sector stimuli). Choices between the gambles revealed that the monkeys used the explicit probability information to make meaningful decisions. Using these cues, we measured probability distortion from choices between the gambles and safe rewards. Parametric modeling of the choices revealed classic probability weighting functions with inverted-S shape. Therefore, the animals overweighted low probability rewards and underweighted high probability rewards. Empirical investigation of the behavior verified that the choices were best explained by a combination of nonlinear value and nonlinear probability distortion. Together, these results suggest that probability distortion may reflect evolutionarily preserved neuronal processing. Copyright © 2015 Stauffer et al.

On Replacing "Quantum Thinking" with Counterfactual Reasoning

NASA Astrophysics Data System (ADS)

Narens, Louis

The probability theory used in quantum mechanics is currently being employed by psychologists to model the impact of context on decision. Its event space consists of closed subspaces of a Hilbert space, and its probability function sometimes violate the law of the finite additivity of probabilities. Results from the quantum mechanics literature indicate that such a "Hilbert space probability theory" cannot be extended in a useful way to standard, finitely additive, probability theory by the addition of new events with specific probabilities. This chapter presents a new kind of probability theory that shares many fundamental algebraic characteristics with Hilbert space probability theory but does extend to standard probability theory by adjoining new events with specific probabilities. The new probability theory arises from considerations about how psychological experiments are related through counterfactual reasoning.

Los padres como maestros de los ninos. Los padres como recursos para los maestros. Serie E: [E1] logro de la participacion de los padres. cuadernos 1 y 2. Edicion para el maestro. Cuadernos para el entrenamiento de maestros de educacion bilingue. (Parents as Their Children's Teachers. Parents as Resources for Teachers. Series E: Parent Participation, Book 1 and 2. Teacher Edition. Bilingual Education Teacher Training Packets).

ERIC Educational Resources Information Center

Lazos, Hector, Comp.

This guide on training bilingual education teachers focuses on parent participation in school activities. The guide addresses three groups of people: paraprofessionals and non-graduate students, bilingual teachers, and graduate students. Two units are presented, one dealing with the important influence parents have on their child's language…

A Visão do Universo Segundo a Concepção de um Grupo de Alunos do Ensino Médio de São Paulo

NASA Astrophysics Data System (ADS)

Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

2005-12-01

Nesse trabalho foi identificada por meio de um questionário a visão de mundo sobre o Universo espaço e tempo entre 270 estudantes de Ensino Médio de três escolas de São Paulo. Constatou-se pouco conhecimento dos temas investigados sendo que apenas 20% dos alunos relacionaram as semanas com as fases da lua enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% reconheciam o Sol como uma estrela. Apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de astronomia seus conceitos ainda são inadequados havendo necessidade de aprimoramento da abordagem desses conteúdos pois apesar de popular a astronomia é veiculada de maneira pouco esclarecedora e com imprecissões.

Del sujeto que ha intentado suicidarse y el Otro: la Institución Psiquiátrica

PubMed Central

Liliana, Mondragón B.; Miguel Ángel, Caballero G.

2009-01-01

El hospital psiquiátrico se ha constituido como un lugar donde se posibilita legitimar la exclusión y la radicalidad de ese otro “que no es igual”, como es el caso del sujeto que atenta contra su propia vida. En consecuencia, el intento de suicidio desde el pensamiento foucaultiano, es una resistencia que desmantela la estructura de dominación a través de un acto de poder, el cual se ejerce sobre el propio cuerpo. Así, la intención de este texto es mostrar que la relación Otro-otro es un lugar en la estructura subjetiva, que se deposita en la institución psiquiátrica, la cual representa el poder, la ley, y es aquello a lo que se le quiere agredir, resistir, abatir con un intento de suicidio. Para demostrar como se materializan estos hechos, se exponen los testimonios de tres adolescentes atendidas en un hospital psiquiátrico por intentos suicidas, en los cuales se señalan los diferentes significados que le atribuyen a la institución psiquiátrica en tanto que representa un Otro en sus actos autoinfligidos. PMID:25400324

[Not Available].

PubMed

Torres Díaz, Cristina V; Martín Peña, Gonzalo; Ezquiaga, Elena; Navas García, Marta; García de Sola, Rafael

2016-07-19

Gracias a los avances técnicos en técnicas neuroquirúrgicas, y debido a que el diagnóstico y la clasificación de las enfermedades psiquiátricas han evolucionado significativamente a lo largo de las últimas décadas, se están desarrollando tratamientos a nivel experimental para aquellos pacientes resistentes al manejo conservador.La anorexia nerviosa es una enfermedad de prevalencia creciente, con la tasa de mortalidad más elevada dentro de los trastornos psiquiátricos, y con aproximadamente un 20% de pacientes que presentan una evolución tórpida. Para estos pacientes que no responden a manejo conservador, la estimulación cerebral profunda ha surgido como una alternativa terapéutica, si bien la literatura especializada al respecto es escasa.A continuación presentamos una revisión de la fisiopatología de la anorexia nerviosa, así como de los distintos tratamientos neuroquirúrgicos realizados a lo largo de la historia. Se detalla la perspectiva de tratamiento quirúrgico actual, así como los aspectos éticos que se han de considerar en relación con el surgimiento de estas nuevas terapias.

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

NASA Astrophysics Data System (ADS)

Rodriguez Ramos, Teresita

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

Myocardial Viability on Cardiac Magnetic Resonance.

PubMed

Souto, Ana Luiza Mansur; Souto, Rafael Mansur; Teixeira, Isabella Cristina Resende; Nacif, Marcelo Souto

2017-05-01

The study of myocardial viability is of great importance in the orientation and management of patients requiring myocardial revascularization or angioplasty. The technique of delayed enhancement (DE) is accurate and has transformed the study of viability into an easy test, not only for the detection of fibrosis but also as a binary test detecting what is viable or not. On DE, fibrosis equal to or greater than 50% of the segmental area is considered as non-viable, whereas that below 50% is considered viable. During the same evaluation, cardiac magnetic resonance (CMR) may also use other techniques for functional and perfusion studies to obtain a global evaluation of ischemic heart disease. This study aims to highlight the current concepts and broadly emphasize the use of CMR as a method that over the last 20 years has become a reference in the detection of infarction and assessment of myocardial viability. Resumo O estudo de viabilidade miocárdica é de grande importância para a orientação e manejo de pacientes que necessitam de cirurgia de revascularização miocárdica ou angioplastia. A técnica de realce tardio (RT) é precisa e transformou o estudo de viabilidade em um teste fácil, não só para a detecção de fibrose, mas também como um modelo binário para a detecção do que é ou não é viável. Uma fibrose identificada pelo RT é considerada como não viável quando igual ou maior do que 50% da área segmentar e como viável quando menor que 50%. A ressonância magnética cardíaca (RMC) também pode lançar mão de outras técnicas para estudo funcional e de perfusão para uma avaliação global da doença isquêmica do coração no mesmo exame. Este estudo tem como objetivo destacar os conceitos atuais e enfatizar amplamente o uso da RMC como um método que nos últimos 20 anos se tornou referência na detecção de infarto e avaliação de viabilidade miocárdica.

Spin-Transfer-Torque Nano-Oscillators: Fabrication, Characterization and Dynamics

NASA Astrophysics Data System (ADS)

Costa, Jose Diogo Teixeira Barbosa

Este trabalho aborda algumas propriedades magneticas e estruturais de nanoparticulas de oxidos e oxidos-hidroxidos de ferro crescidos em matrizes hibridas orgânicas-inorgânicas. As matrizes hibridas, denominadas di-ureasils e obtidas pelo processo sol-gel, sao compostas por uma rede siliciosa ligada covalentemente por pontes ureia a cadeias orgânicas de diferente peso molecular. A estrutura local dos di-ureasils nao dopados esta modelada como grupos de dominios siliciosos com dimensoes nanometricas, estruturalmente correlacionados no seio de uma matriz rica em polimero. Neste trabalho mostra-se que os di-ureasils permitem o crescimento controlado de oxidos e oxidos-hidroxidos de ferro, incluindo a magnetite, maguemite, oxihidroxinitrato de ferro e ferrihidrite. O crescimento das nanoparticulas de ferrihidrite da-se em condicoes acidas a superficie dos dominios siliciosos, junto aos grupos carbonilo, que funcionam como pontos de nucleacao. Desse modo da-se uma nucleacao heterogenea, onde o tamanho das nanoparticulas depende da concentracao de ferro (entre 1 e 6% em massa), sendo a concentracao de particulas constante. As propriedades magneticas das nanoparticulas de ferrihidrite revelam a existencia de interaccoes antiferromagneticas e de momentos descompensados. A contribuicao destas duas componentes nas curvas de magnetizacao em funcao do campo magnetico pode ser separada usando um metodo aqui proposto, o que permite um adequado estudo da evolucao do momento magnetico com a temperatura. O estudo das propriedades magneticas dinâmicas das particulas de ferrihidrite, atraves de susceptibilidade ac, medidas de relaxacao e medidas de efeito Mossbauer, permitiu estudar a evolucao das interaccoes dipolares em funcao da concentracao de ferro, bem como determinar a distribuicao de barreiras de energia de anisotropia no caso em que essas interaccoes sao desprezaveis. E apresentado um novo metodo para comparacao desta distribuicao com a distribuicao de tamanhos, que permitiu concluir que os momentos magneticos descompensados estao aleatoriamente distribuidos em volume. Usando baixas concentracoes de agua, foi possivel crescer fases de oxihidroxinitrato de ferro com diferentes graus de cristalinidade, sendo algumas precursoras da ferrihidrite (como observado noutros trabalhos) e sendo outras novas fases. O crescimento de nanoparticulas de maguemite e magnetite acontece apos incorporacao de ioes de Fe2+ e Fe3+ seguidos de tratamento basico e termico. Estes sistemas apresentam propriedades magneticas tipicas de nanoparticulas superparamagneticas sem interaccoes dipolares. As propriedades magneticas dependem criticamente da existencia de grupos isocianato livres, que actuarao como pontos de nucleacao. None

Structural and Magnetic Studies on Iron Oxide Nanoparticles in Hybrid Matrices =

NASA Astrophysics Data System (ADS)

Silva, Nuno Joao de Oliveira

Este trabalho aborda algumas propriedades magneticas e estruturais de nanoparticulas de oxidos e oxidos-hidroxidos de ferro crescidos em matrizes hibridas orgânicas-inorgânicas. As matrizes hibridas, denominadas di-ureasils e obtidas pelo processo sol-gel, sao compostas por uma rede siliciosa ligada covalentemente por pontes ureia a cadeias orgânicas de diferente peso molecular. A estrutura local dos di-ureasils nao dopados esta modelada como grupos de dominios siliciosos com dimensoes nanometricas, estruturalmente correlacionados no seio de uma matriz rica em polimero. Neste trabalho mostra-se que os di-ureasils permitem o crescimento controlado de oxidos e oxidos-hidroxidos de ferro, incluindo a magnetite, maguemite, oxihidroxinitrato de ferro e ferrihidrite. O crescimento das nanoparticulas de ferrihidrite da-se em condicoes acidas a superficie dos dominios siliciosos, junto aos grupos carbonilo, que funcionam como pontos de nucleacao. Desse modo da-se uma nucleacao heterogenea, onde o tamanho das nanoparticulas depende da concentracao de ferro (entre 1 e 6% em massa), sendo a concentracao de particulas constante. As propriedades magneticas das nanoparticulas de ferrihidrite revelam a existencia de interaccoes antiferromagneticas e de momentos descompensados. A contribuicao destas duas componentes nas curvas de magnetizacao em funcao do campo magnetico pode ser separada usando um metodo aqui proposto, o que permite um adequado estudo da evolucao do momento magnetico com a temperatura. O estudo das propriedades magneticas dinâmicas das particulas de ferrihidrite, atraves de susceptibilidade ac, medidas de relaxacao e medidas de efeito Mossbauer, permitiu estudar a evolucao das interaccoes dipolares em funcao da concentracao de ferro, bem como determinar a distribuicao de barreiras de energia de anisotropia no caso em que essas interaccoes sao desprezaveis. E apresentado um novo metodo para comparacao desta distribuicao com a distribuicao de tamanhos, que permitiu concluir que os momentos magneticos descompensados estao aleatoriamente distribuidos em volume. Usando baixas concentracoes de agua, foi possivel crescer fases de oxihidroxinitrato de ferro com diferentes graus de cristalinidade, sendo algumas precursoras da ferrihidrite (como observado noutros trabalhos) e sendo outras novas fases. O crescimento de nanoparticulas de maguemite e magnetite acontece apos incorporacao de ioes de Fe2+ e Fe3+ seguidos de tratamento basico e termico. Estes sistemas apresentam propriedades magneticas tipicas de nanoparticulas superparamagneticas sem interaccoes dipolares. As propriedades magneticas dependem criticamente da existencia de grupos isocianato livres, que actuarao como pontos de nucleacao. None

El rol de Ia colaboracion y el Modelo de Aprendizaje Basado en Proyectos (ABPr) mediante el lente de la Teoria de Actividad (CHAT): un estudio de caso con estudiantes de 9no grado

NASA Astrophysics Data System (ADS)

Delgado, Isabel C.

Los modelos de eensenanza y aprendizaje constructivistas conceptualizan el aprendizaje como un proceso activo. El modelo de Aprendizaje Basado en Proyectos (ABPr) se distingue por una serie de componentes, entre los cuales se destaca el aspecto colaborativo y cooperativo como un reto al momento de su implantacion. Son pocas las investigaciones que se concentran en este aspecto del modelo. En este estudio, se analizaron las diversas interacciones que surgen durante la implantacion de una unidad curricular sobre el tema de Geologia de Puerto Rico, la cual se diseno con el modelo ABPr cuyo enfoque es orientacion a proyectos. Particularmente, se examinaron las interacciones sociales que surgen entre los pares y entre pares y docente durante el proceso de planificacion y desarrollo de los productos finales, al igual que las interacciones entre los estudiantes y el material didactico en estas etapas del modelo. La investigacion es de tipo cualitativo e incorpora como diseno el estudio de caso. Las diversas interacciones constituyen la unidad de analisis. En el estudio participaron 19 estudiantes de 9no grado, a quienes se organizaron en 5 grupos colaborativos por temas de interes (Pangea, Placas tectonicas, Volcanes, Tsunamis y Terremotos). Las tecnicas que se utilizaron para recopilar los datos fueron: observaciones participativas, grupos focales y analisis de documentos (cuadernos reflexivos y respuestas de los estudiantes a la pregunta central del proyecto). Para el analisis de los datos se aplico la teoria de actividad (CHAT) que concentra la unidad de analisis en la actividad humana en un contexto particular. Los resultados del estudio senalan que las interacciones entre pares, entre pares y docente, asi como entre estudiantes y material didactico son fundamentales en el proceso de aprendizaje. Una mayor interaccion entre pares durante las etapas de planificar y desarrollar los productos finales de la unidad, promueve una mejor comprension de los conceptos de la unidad, segun evidencia los productos finales del ABPr. La interaccion con el docente es muy importante para mediar los conflictos y desacuerdos que surgen como parte de las interacciones entre pares. Por lo tanto, el uso de diversas estrategias de andamiaje por parte del docente durante las reuniones de los grupos colaborativos es esencial para el exito del modelo ABPr.

A proposed contents astronomy for basic education

NASA Astrophysics Data System (ADS)

Albrecht, E.; Voelzke, M. R.

2014-08-01

A Astronomia é um tema que sempre exerceu fascínio sobre as pessoas de um modo geral. Conhecer e estudar o que há nos “céus”, além de nossos olhos, continua sendo instigador e de grande interesse. Baseado nestas justificativas desenvolveu-se uma pesquisa de Doutorado, na qual, o objetivo principal foi investigar sobre a presença dos conteúdos de Astronomia nas Propostas Curriculares da região Sul do Brasil, a saber, os estados de Paraná, Rio Grande do Sul e Santa Catarina e, posterior comparação com os Parâmetros Curriculares Nacionais (PCN) que trazem propostas de conteúdos para toda a Educação Básica brasileira. Tal investigação pautou-se na abordagem de caráter qualitativo e utilizouse para tal da Análise de Conteúdos (Bardin, 2011), que possibilitou a construção de quatro categorias, nas quais os conteúdos astronômicos foram agrupados: Terra, Sistema Solar, Via Láctea e Universo. Após a leitura, coleta de dados, construção de categorias, observou-se a dicotomia na apresentação destes conteúdos. As propostas curriculares analisadas foram as de Geografia, Ciências e Física dos estados do Paraná (2008), Rio Grande do Sul (2009) e de Santa Catarina (1998), responsáveis pelo trabalho com Astronomia nestes estados. No Ensino Fundamental, a proposta curricular do estado do Paraná apresenta conteúdos ligados à Astronomia desde o sexto ano até o nono ano, como conteúdo do primeiro bimestre, o que também é apresentado na proposta curricular do estado do Rio Grande do Sul, porém, este, não divide os conteúdos por bimestre e nem por ano, mas por ciclos, sexto e sétimo anos como primeiro ciclo e oitavo e nono anos como segundo ciclo, deixando livre para o professor estruturar sua sequência de conteúdos. A proposta curricular de Santa Catarina não apresenta estes conteúdos de maneira explícita, não divide dos conteúdos nem por ano, nem por série, traz uma sequência de conteúdos para serem trabalhados ao longo dos quatro anos, nos quais, aparecem timidamente alguns conteúdos de Astronomia. Para o Ensino Médio, as propostas curriculares do Paraná e de Santa Catarina parecem que se repetem, apresentando apenas o conteúdo Gravitação Universal, na primeira série do Ensino Médio, já a proposta curricular do Rio Grande do Sul, traz uma sequência que é proposta nos PCN (Brasil, 1998; 1999; 2002), na qual aparece o tema em questão, porém, em todos os anos, em todas as propostas, não há um detalhamento do que, de como trabalhar os conteúdos. O detalhamento facilita a prática pedagógica, pois, conteúdos simples como as Estações do Ano, Fases da Lua, sequer são citados nas propostas curriculares pesquisadas. Outro aspecto observado é que os conteúdos de um modo geral não trazem uma sequência e não primam por partir do entorno do aluno, daquilo que ele conhece para estruturar novos conceitos. Tais aspectos dificultam o fazer pedagógico, pois, por ser uma região com características culturais semelhantes, era esperado que as propostas fossem mais próximas, o! que facilitaria em muito, por exemplo, transferências dentro de um mesmo estado ou interestaduais. Pautando-se no que foi observado, na falta de especificidade dos conteúdos, clareza, sequência dos conteúdos e propostas de trabalho é proposto uma sequência de conteúdos de Astronomia, com materiais e recursos, pois, como apontado por Langhi e Nardi (2009), é necessário fornecer além da informação, do conteúdo, o como fazer. Tal proposta não visa estabelecer-se como regra, mas como suporte ao professor para facilitar sua prática pedagógica e tornar o trabalho com Astronomia presente nas escolas brasileiras. Bardin, L. Análise de conteúdo. Tradução Luís Antero Reto, Augusto Pinheiro. São Paulo: Edições 70, 2011. 279 p. Langhi, R; Nardi, R. Ensino da astronomia no Brasil: educação formal, informal, não-formal e divulgação científica. Revista Brasileira de Ensino de Física, v. 31, n. 4, p. 4402-1 a 4402-11, 2009.

ERP Correlates of Verbal and Numerical Probabilities in Risky Choices: A Two-Stage Probability Processing View

PubMed Central

Li, Shu; Du, Xue-Lei; Li, Qi; Xuan, Yan-Hua; Wang, Yun; Rao, Li-Lin

2016-01-01

Two kinds of probability expressions, verbal and numerical, have been used to characterize the uncertainty that people face. However, the question of whether verbal and numerical probabilities are cognitively processed in a similar manner remains unresolved. From a levels-of-processing perspective, verbal and numerical probabilities may be processed differently during early sensory processing but similarly in later semantic-associated operations. This event-related potential (ERP) study investigated the neural processing of verbal and numerical probabilities in risky choices. The results showed that verbal probability and numerical probability elicited different N1 amplitudes but that verbal and numerical probabilities elicited similar N2 and P3 waveforms in response to different levels of probability (high to low). These results were consistent with a levels-of-processing framework and suggest some internal consistency between the cognitive processing of verbal and numerical probabilities in risky choices. Our findings shed light on possible mechanism underlying probability expression and may provide the neural evidence to support the translation of verbal to numerical probabilities (or vice versa). PMID:26834612

Knowing where is different from knowing what: Distinct response time profiles and accuracy effects for target location, orientation, and color probability.

PubMed

Jabar, Syaheed B; Filipowicz, Alex; Anderson, Britt

2017-11-01

When a location is cued, targets appearing at that location are detected more quickly. When a target feature is cued, targets bearing that feature are detected more quickly. These attentional cueing effects are only superficially similar. More detailed analyses find distinct temporal and accuracy profiles for the two different types of cues. This pattern parallels work with probability manipulations, where both feature and spatial probability are known to affect detection accuracy and reaction times. However, little has been done by way of comparing these effects. Are probability manipulations on space and features distinct? In a series of five experiments, we systematically varied spatial probability and feature probability along two dimensions (orientation or color). In addition, we decomposed response times into initiation and movement components. Targets appearing at the probable location were reported more quickly and more accurately regardless of whether the report was based on orientation or color. On the other hand, when either color probability or orientation probability was manipulated, response time and accuracy improvements were specific for that probable feature dimension. Decomposition of the response time benefits demonstrated that spatial probability only affected initiation times, whereas manipulations of feature probability affected both initiation and movement times. As detection was made more difficult, the two effects further diverged, with spatial probability disproportionally affecting initiation times and feature probability disproportionately affecting accuracy. In conclusion, all manipulations of probability, whether spatial or featural, affect detection. However, only feature probability affects perceptual precision, and precision effects are specific to the probable attribute.

Bayesics

NASA Astrophysics Data System (ADS)

Skilling, John

2005-11-01

This tutorial gives a basic overview of Bayesian methodology, from its axiomatic foundation through the conventional development of data analysis and model selection to its rôle in quantum mechanics, and ending with some comments on inference in general human affairs. The central theme is that probability calculus is the unique language within which we can develop models of our surroundings that have predictive capability. These models are patterns of belief; there is no need to claim external reality. 1. Logic and probability 2. Probability and inference 3. Probability and model selection 4. Prior probabilities 5. Probability and frequency 6. Probability and quantum mechanics 7. Probability and fundamentalism 8. Probability and deception 9. Prediction and truth

Excluding joint probabilities from quantum theory

NASA Astrophysics Data System (ADS)

Allahverdyan, Armen E.; Danageozian, Arshag

2018-03-01

Quantum theory does not provide a unique definition for the joint probability of two noncommuting observables, which is the next important question after the Born's probability for a single observable. Instead, various definitions were suggested, e.g., via quasiprobabilities or via hidden-variable theories. After reviewing open issues of the joint probability, we relate it to quantum imprecise probabilities, which are noncontextual and are consistent with all constraints expected from a quantum probability. We study two noncommuting observables in a two-dimensional Hilbert space and show that there is no precise joint probability that applies for any quantum state and is consistent with imprecise probabilities. This contrasts with theorems by Bell and Kochen-Specker that exclude joint probabilities for more than two noncommuting observables, in Hilbert space with dimension larger than two. If measurement contexts are included into the definition, joint probabilities are not excluded anymore, but they are still constrained by imprecise probabilities.

An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks.

PubMed

He, Jieyue; Wang, Chunyan; Qiu, Kunpu; Zhong, Wei

2014-01-01

Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. The algorithm of probability graph isomorphism evaluation based on circuit simulation method excludes most of subgraphs which are not probability isomorphism and reduces the search space of the probability isomorphism subgraphs using the mismatch values in the node voltage set. It is an innovative way to find the frequent probability patterns, which can be efficiently applied to probability motif discovery problems in the further studies.

An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks

PubMed Central

2014-01-01

Background Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. Methods In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. Results The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. Conclusions The algorithm of probability graph isomorphism evaluation based on circuit simulation method excludes most of subgraphs which are not probability isomorphism and reduces the search space of the probability isomorphism subgraphs using the mismatch values in the node voltage set. It is an innovative way to find the frequent probability patterns, which can be efficiently applied to probability motif discovery problems in the further studies. PMID:25350277

Heuristics can produce surprisingly rational probability estimates: Comment on Costello and Watts (2014).

PubMed

Nilsson, Håkan; Juslin, Peter; Winman, Anders

2016-01-01

Costello and Watts (2014) present a model assuming that people's knowledge of probabilities adheres to probability theory, but that their probability judgments are perturbed by a random noise in the retrieval from memory. Predictions for the relationships between probability judgments for constituent events and their disjunctions and conjunctions, as well as for sums of such judgments were derived from probability theory. Costello and Watts (2014) report behavioral data showing that subjective probability judgments accord with these predictions. Based on the finding that subjective probability judgments follow probability theory, Costello and Watts (2014) conclude that the results imply that people's probability judgments embody the rules of probability theory and thereby refute theories of heuristic processing. Here, we demonstrate the invalidity of this conclusion by showing that all of the tested predictions follow straightforwardly from an account assuming heuristic probability integration (Nilsson, Winman, Juslin, & Hansson, 2009). We end with a discussion of a number of previous findings that harmonize very poorly with the predictions by the model suggested by Costello and Watts (2014). (c) 2015 APA, all rights reserved).

Probability concepts in quality risk management.

PubMed

Claycamp, H Gregg

2012-01-01

Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although risk is generally a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management tools are relatively silent on the meaning and uses of "probability." The probability concept is typically applied by risk managers as a combination of frequency-based calculation and a "degree of belief" meaning of probability. Probability as a concept that is crucial for understanding and managing risk is discussed through examples from the most general, scenario-defining and ranking tools that use probability implicitly to more specific probabilistic tools in risk management. A rich history of probability in risk management applied to other fields suggests that high-quality risk management decisions benefit from the implementation of more thoughtful probability concepts in both risk modeling and risk management. Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although "risk" generally describes a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management methodologies and respective tools focus on managing severity but are relatively silent on the in-depth meaning and uses of "probability." Pharmaceutical manufacturers are expanding their use of quality risk management to identify and manage risks to the patient that might occur in phases of the pharmaceutical life cycle from drug development to manufacture, marketing to product discontinuation. A probability concept is typically applied by risk managers as a combination of data-based measures of probability and a subjective "degree of belief" meaning of probability. Probability as a concept that is crucial for understanding and managing risk is discussed through examples from the most general, scenario-defining and ranking tools that use probability implicitly to more specific probabilistic tools in risk management.

Implementation of the Iterative Proportion Fitting Algorithm for Geostatistical Facies Modeling

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

Li Yupeng, E-mail: yupeng@ualberta.ca; Deutsch, Clayton V.

2012-06-15

In geostatistics, most stochastic algorithm for simulation of categorical variables such as facies or rock types require a conditional probability distribution. The multivariate probability distribution of all the grouped locations including the unsampled location permits calculation of the conditional probability directly based on its definition. In this article, the iterative proportion fitting (IPF) algorithm is implemented to infer this multivariate probability. Using the IPF algorithm, the multivariate probability is obtained by iterative modification to an initial estimated multivariate probability using lower order bivariate probabilities as constraints. The imposed bivariate marginal probabilities are inferred from profiles along drill holes or wells.more » In the IPF process, a sparse matrix is used to calculate the marginal probabilities from the multivariate probability, which makes the iterative fitting more tractable and practical. This algorithm can be extended to higher order marginal probability constraints as used in multiple point statistics. The theoretical framework is developed and illustrated with estimation and simulation example.« less

The Science Teachers and Their way of Thinking about Astronomy. (Spanish Title: Los Profesores de Ciencias y Sus Formas de Pensar la Astronomía.) Os Professores de Ciências e Suas Formas de Pensar a Astronomia

NASA Astrophysics Data System (ADS)

Leite, Cristina; Hosoume, Yassuko

2007-12-01

The research presented in this article is about the way science teachers from Elementary School think about astronomical elements. Its methodology is based on semi-structured interviews, which were video recorded. The research is centered in a three-dimensional perspective of astronomical Earth, the Sun, the Moon, the planets and the stars, and also the conceptions about sky and Universe. The esults indicate a Universe that contains: Sun, stars, planets and Moon; where the Solar System is a little part of the whole. Sometimes they think that the Solar System is the Universe. The objects are in the sky or in the Universe, which, for many of them, is only the space above the Earth. The flat shape of astronomical objects and the spatial structure of the Universe are striking features. Many of them think that Sun and stars are different: the Sun is a hot object and the stars are cold ones. These results worry us and they certainly indicate how urgent it is to plan Professional Development in Astronomy for teachers, after all the PCN's emphasize that this subject is important to be taught. El objeto de investigación de este artículo es la manera de pensar sobre los elementos de la Astronomía de los profesores de Ciencias en la enseñanza fundamental. La metodología consiste en entrevistas semi-estructuradas, filmadas en video y centradas en la tridimensionalidad de los elementos astronómicos, para posibilitar un mapeamiento de las concepciones sobre las formas y dimensiones de la Tierra, del Sol, de la Luna, de los planetas y de las estrellas, como también de la concepción de cielo y de Universo en su totalidad. Los resultados indican un Universo conteniendo: Sol, estrellas, planetas y Luna, donde el Sistema Solar se ubica como parte. Algunas veces, el Universo es concebido como el propio Sistema Solar. Los objetos están en el cielo o en el Universo, que, para muchos, se restringe al espacio que está arriba de la Tierra. La forma plana de los objetos astronómicos y la estructura espacial del montaje del Universo son características fundamentales. Muchos indican Sol y estrellas como cosas distintas: el Sol es un objeto caliente y las estrellas son frías. Esos resultados nos preocupan y ciertamente señalan una urgencia de programas de formación continuada para profesores en el contenido de astronomía, pues los PCN's (Parámetros Curriculares Nacionales) recomiendan con énfasis la enseñanza de este contenido. O modo de pensar dos professores de Ciências do ensino fundamental sobre os elementos da Astronomia é o objeto de pesquisa presente neste artigo, cuja metodologia consiste em entrevistas semiestruturadas, filmadas em vídeo e centradas numa perspectiva tridimensional dos elementos astronômicos, possibilitando um mapeamento das concepções das formas e das dimensões da Terra, do Sol, da Lua, dos planetas e das estrelas, bem como da concepção de céu e de Universo como um todo. Os resultados indicam um Universo contendo: Sol, estrelas, planetas e Lua, onde o Sistema Solar é parte do todo. Algumas vezes o Universo é concebido como o próprio Sistema Solar. Os objetos estão no céu ou no Universo o qual, para muitos, se restringe ao espaço que está acima da Terra. A forma plana dos objetos astronômicos e a estrutura espacial da montagem do Universo são características marcantes. Muitos indicam Sol e estrelas como coisas diferentes: Sol é um objeto quente e as estrelas são frias. Esses resultados nos preocupam e certamente sinalizam uma urgência de programas de formação continuada para professores no conteúdo de astronomia, uma vez que os PCN's indicam fortemente o ensino desse conteúdo.

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

NASA Astrophysics Data System (ADS)

Ferreres Sabater, Agustin

Cualquier sistema electronico que incluya un procesado o tratamiento de la senal, y ademas, algun tipo de actuador mecanico generalmente necesita, como minimo, dos tensiones diferentes de alimentacion. Excluyendo los sistemas de alimentacion distribuida, la solucion tecnica mas utilizada para proporcionar dos o mas tensiones consiste en las fuentes de alimentacion multisalida. En una fuente de alimentacion multisalida los diferentes circuitos que conforman cada salida comparten un mismo transformador de potencia optimizando coste, masa, y volumen. Las ventajas obtenidas con este procedimiento tienen en su contra el efecto que sobre cada salida individual provocan las demas en su conjunto debido, principalmente, a los efectos de los elementos parasitos de los componentes. Un cambio de carga en una de las salidas produce un transitorio que es visto por todas las demas como un efecto de impedancia cruzada, y al final del transitorio, la tension de cada salida es diferente respecto a la que tenian antes del transitorio. Este ultimo resultado se conoce como regulacion cruzada. La disminucion de los efectos de la regulacion cruzada ha sido objeto de estudio durante los ultimos anos. El objetivo ha sido el desarrollo de distintas estrategias que permiten, desde disminuir los efectos de la regulacion cruzada hasta los niveles deseables, a eliminarla completamente. El resultado final suele suponer una penalizacion sobre el diseno del sistema directamente proporcional al grado de regulacion a conseguir en las distintas salidas. Entre las soluciones propuestas para eliminar la regulacion cruzada las tecnicas de post-regulacion se han consolidado como la opcion mas aceptada ya que, pueden aplicarse a cualquier convertidor y no suponen ninguna complejidad adicional a la hora de plantear el diseno. En esta Tesis Doctoral se abordara el estudio de la tecnica conocida como postregulacion mediante transformador controlado, que si bien se ha empleado en convertidores resonantes, su modelizacion, y aplicacion en convertidores PWM, esta aun por estudiar y valorar. El primer Capitulo consiste en una breve introduccion al problema de la regulacion cruzada y la impedancia cruzada para posteriormente describir las tecnicas de post-regulacion actualmente mas empleadas, con especial atencion al post-regulador con transformador controlado. El Capitulo segundo trata del estudio de las caracteristicas estaticas del postregulador con transformador controlado. Partiendo de los estudios disponibles sobre el postregulador se plantean mejoras en su modo de actuacion y se discuten tres alternativas diferentes para controlar el transformador. Las dos primeras consisten en emplear un convertidor auxiliar Boost en sus dos modos de funcionamiento, continuo y discontinuo. La tercera consiste en controlar el transformador con una tension PWM directamente, sin filtrado. Finalmente se comprueba experimentalmente, para el estado estacionario, el funcionamiento del post-regulador para cada uno de los tres metodos de control. El Capitulo tercero trata de la dinamica de la salida controlada con el post-regulador cuando este emplea un convertidor auxiliar tipo Boost. Mediante la tecnica de promediado de variables de estado se propone el modelo de pequena senal, tanto para el modo continuo como para el modo discontinuo de funcionamiento del convertidor auxiliar. Los resultados mas significativos de esta seccion son las expresiones analiticas de las impedancias cruzadas y de la impedancia de la salida post-regulada. Como complemento al modelo de pequena senal se plantea un modelo de gran senal implementado sobre el simulador Pspice. Con este nuevo modelo se reproducen los resultados obtenidos con el modelo de pequena senal y ademas es posible simular los transitorios en las tensiones de salida ante cambios de carga. La modelizacion del convertidor cuando el transformador se controla con una tension PWM sin filtrar es el objetivo del Capitulo 4. En las secciones siguientes del Capitulo se plantea el correspondiente modelo de gran senal aplicado a un nuevo prototipo experimental, de mayor tension de entrada y mayores corrientes de salida. El final del Capitulo contrasta los resultados experimentales con los teoricos confirmando la utilidad del modelo de gran senal como una herramienta basica de diseno. Finalmente, en el Capitulo 5, se presentan las conclusiones y la valoracion de los diferentes estudios plateados a lo largo de la Tesis Doctoral.

Approved Methods and Algorithms for DoD Risk-Based Explosives Siting

DTIC Science & Technology

2007-02-02

glass. Pgha Probability of a person being in the glass hazard area Phit Probability of hit Phit (f) Probability of hit for fatality Phit (maji...Probability of hit for major injury Phit (mini) Probability of hit for minor injury Pi Debris probability densities at the ES PMaj (pair) Individual...combined high-angle and combined low-angle tables. A unique probability of hit is calculated for the three consequences of fatality, Phit (f), major injury

Experimental Probability in Elementary School

ERIC Educational Resources Information Center

Andrew, Lane

2009-01-01

Concepts in probability can be more readily understood if students are first exposed to probability via experiment. Performing probability experiments encourages students to develop understandings of probability grounded in real events, as opposed to merely computing answers based on formulae.

Psychophysics of the probability weighting function

NASA Astrophysics Data System (ADS)

Takahashi, Taiki

2011-03-01

A probability weighting function w(p) for an objective probability p in decision under risk plays a pivotal role in Kahneman-Tversky prospect theory. Although recent studies in econophysics and neuroeconomics widely utilized probability weighting functions, psychophysical foundations of the probability weighting functions have been unknown. Notably, a behavioral economist Prelec (1998) [4] axiomatically derived the probability weighting function w(p)=exp(-() (0<α<1 and w(0)=1,w(1e)=1e,w(1)=1), which has extensively been studied in behavioral neuroeconomics. The present study utilizes psychophysical theory to derive Prelec's probability weighting function from psychophysical laws of perceived waiting time in probabilistic choices. Also, the relations between the parameters in the probability weighting function and the probability discounting function in behavioral psychology are derived. Future directions in the application of the psychophysical theory of the probability weighting function in econophysics and neuroeconomics are discussed.

Vaccination with Dendritic Cell Myeloma Fusions in Conjunction with Stem Cell Transplantation and PD-1 Blockade

DTIC Science & Technology

2014-05-01

UNRELATED DEFINITE NONE RESOLVED PM34 Injection site reaction 9/5/2013 1 UNRELATED DEFINITE (GM-CSF) NONE RESOLVED PM35 Neutropenia 10/8/2013 3 PROBABLE...PROBABLE NONE RESOLVED PM35 Neutropenia 10/11/2013 4 PROBABLE PROBABLE NONE RESOLVED PM35 Neutropenia 10/15/2013 3 PROBABLE PROBABLE NONE RESOLVED...presented to clinic for week 2 follow-up after his second infusion of CT-011 with grade 4 neutropenia (expected, probably related to CT-011 and

Vaccination with Dendritic Cell Myeloma Fusions in Conjuction with Stem Cell Transplantation and PD-1 Blockade

DTIC Science & Technology

2015-07-01

Definite (GM- CSF) None Resolved PM35 Neutropenia 10/8/2013 3 Probable Probable None Resolved PM35 Neutropenia 10/11/2013 4 Probable Probable None...Resolved PM35 Neutropenia 10/15/2013 3 Probable Probable None Resolved 13 Subject ID AE Start Date CTC Grade Relationship to CT-011...participant PM35 presented to clinic for week 2 follow-up after his second infusion of CT-011 with grade 4 neutropenia (expected, probably related

[Leadership and CETREMI].

PubMed

Sandoval-Gutiérrez, José Luis

2017-01-01

Según la Real Academia Española, el término «líder» significa «persona que dirige u orienta a un grupo, que reconoce su autoridad». Es importante este término ya que es muy ambiguo, porque no reconoce el nivel moral o la empatía que puede ejercer una persona en determinado grupo al reconocerlo como líder, y no solo con la autoridad que este puede ejercer en el mismo, siendo este último concepto algo muy común en el mundo anglosajón, denominándose líder a alguien que tiene un puesto de autoridad, lo cual se puede confundir con lo que conocemos como «jefe».

Distribución del continuo ultravioleta e infrarrojo en estrellas Be

NASA Astrophysics Data System (ADS)

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

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

Perspectivas Futuras para o Observatório do Pico dos Dias

NASA Astrophysics Data System (ADS)

Bruch, Albert

2004-02-01

Com o Observatório Gemini plenamente operacional e o telescópio SOAR iniciando suas operações em breve, a astronomia observacional brasileira encontra-se no auge de uma transformação profunda que terá um impacto grave no Observatório do Pico dos Dias - OPD. Refletimos aqui sobre a natureza desse impacto e estratégias para manter a competitividade do OPD. Não queremos apresentar receitas prontas, mas idéias que poderão servir como base de discussão sobre o uso inteligente dos telescópios do OPD como parte do conjunto de instrumentos disponíveis à comunidade astronômica brasileira.

Conceptos Basicos Sobre el Gas Natural (in Spanish)

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

El gas natural abastece cerca de 150.000 vehiculos en los Estados Unidos y aproximadamente 22 millones de vehiculos en todo el mundo. Los vehiculos de gas natural (NGV, por sus siglas en ingles) son una buena opcion para las flotas de vehiculos de alto kilometraje, tales como autobuses, taxis, vehiculos de recoleccion de basura, los cuales son alimentados centralmente u operan dentro de un area limitada o a lo largo de una ruta con estaciones de servicio de gas natural. Las ventajas del gas natural como combustible alternativo incluyen su disponibilidad interna, la red de distribucion establecida, un costo relativamentemore » bajo, y los beneficios de las emisiones.« less

Estimation of post-test probabilities by residents: Bayesian reasoning versus heuristics?

PubMed

Hall, Stacey; Phang, Sen Han; Schaefer, Jeffrey P; Ghali, William; Wright, Bruce; McLaughlin, Kevin

2014-08-01

Although the process of diagnosing invariably begins with a heuristic, we encourage our learners to support their diagnoses by analytical cognitive processes, such as Bayesian reasoning, in an attempt to mitigate the effects of heuristics on diagnosing. There are, however, limited data on the use ± impact of Bayesian reasoning on the accuracy of disease probability estimates. In this study our objective was to explore whether Internal Medicine residents use a Bayesian process to estimate disease probabilities by comparing their disease probability estimates to literature-derived Bayesian post-test probabilities. We gave 35 Internal Medicine residents four clinical vignettes in the form of a referral letter and asked them to estimate the post-test probability of the target condition in each case. We then compared these to literature-derived probabilities. For each vignette the estimated probability was significantly different from the literature-derived probability. For the two cases with low literature-derived probability our participants significantly overestimated the probability of these target conditions being the correct diagnosis, whereas for the two cases with high literature-derived probability the estimated probability was significantly lower than the calculated value. Our results suggest that residents generate inaccurate post-test probability estimates. Possible explanations for this include ineffective application of Bayesian reasoning, attribute substitution whereby a complex cognitive task is replaced by an easier one (e.g., a heuristic), or systematic rater bias, such as central tendency bias. Further studies are needed to identify the reasons for inaccuracy of disease probability estimates and to explore ways of improving accuracy.

Probability based models for estimation of wildfire risk

Treesearch

Haiganoush Preisler; D. R. Brillinger; R. E. Burgan; John Benoit

2004-01-01

We present a probability-based model for estimating fire risk. Risk is defined using three probabilities: the probability of fire occurrence; the conditional probability of a large fire given ignition; and the unconditional probability of a large fire. The model is based on grouped data at the 1 km²-day cell level. We fit a spatially and temporally explicit non-...

Surprisingly rational: probability theory plus noise explains biases in judgment.

PubMed

Costello, Fintan; Watts, Paul

2014-07-01

The systematic biases seen in people's probability judgments are typically taken as evidence that people do not use the rules of probability theory when reasoning about probability but instead use heuristics, which sometimes yield reasonable judgments and sometimes yield systematic biases. This view has had a major impact in economics, law, medicine, and other fields; indeed, the idea that people cannot reason with probabilities has become a truism. We present a simple alternative to this view, where people reason about probability according to probability theory but are subject to random variation or noise in the reasoning process. In this account the effect of noise is canceled for some probabilistic expressions. Analyzing data from 2 experiments, we find that, for these expressions, people's probability judgments are strikingly close to those required by probability theory. For other expressions, this account produces systematic deviations in probability estimates. These deviations explain 4 reliable biases in human probabilistic reasoning (conservatism, subadditivity, conjunction, and disjunction fallacies). These results suggest that people's probability judgments embody the rules of probability theory and that biases in those judgments are due to the effects of random noise. (c) 2014 APA, all rights reserved.

Probability Theory Plus Noise: Descriptive Estimation and Inferential Judgment.

PubMed

Costello, Fintan; Watts, Paul

2018-01-01

We describe a computational model of two central aspects of people's probabilistic reasoning: descriptive probability estimation and inferential probability judgment. This model assumes that people's reasoning follows standard frequentist probability theory, but it is subject to random noise. This random noise has a regressive effect in descriptive probability estimation, moving probability estimates away from normative probabilities and toward the center of the probability scale. This random noise has an anti-regressive effect in inferential judgement, however. These regressive and anti-regressive effects explain various reliable and systematic biases seen in people's descriptive probability estimation and inferential probability judgment. This model predicts that these contrary effects will tend to cancel out in tasks that involve both descriptive estimation and inferential judgement, leading to unbiased responses in those tasks. We test this model by applying it to one such task, described by Gallistel et al. ). Participants' median responses in this task were unbiased, agreeing with normative probability theory over the full range of responses. Our model captures the pattern of unbiased responses in this task, while simultaneously explaining systematic biases away from normatively correct probabilities seen in other tasks. Copyright © 2018 Cognitive Science Society, Inc.

Quantum probabilities as Dempster-Shafer probabilities in the lattice of subspaces

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

Vourdas, A.

2014-08-15

The orthocomplemented modular lattice of subspaces L[H(d)], of a quantum system with d-dimensional Hilbert space H(d), is considered. A generalized additivity relation which holds for Kolmogorov probabilities is violated by quantum probabilities in the full lattice L[H(d)] (it is only valid within the Boolean subalgebras of L[H(d)]). This suggests the use of more general (than Kolmogorov) probability theories, and here the Dempster-Shafer probability theory is adopted. An operator D(H{sub 1},H{sub 2}), which quantifies deviations from Kolmogorov probability theory is introduced, and it is shown to be intimately related to the commutator of the projectors P(H{sub 1}),P(H{sub 2}), to the subspacesmore » H{sub 1}, H{sub 2}. As an application, it is shown that the proof of the inequalities of Clauser, Horne, Shimony, and Holt for a system of two spin 1/2 particles is valid for Kolmogorov probabilities, but it is not valid for Dempster-Shafer probabilities. The violation of these inequalities in experiments supports the interpretation of quantum probabilities as Dempster-Shafer probabilities.« less

The Irrelevance of the Risk-Uncertainty Distinction.

PubMed

Roser, Dominic

2017-10-01

Precautionary Principles are often said to be appropriate for decision-making in contexts of uncertainty such as climate policy. Contexts of uncertainty are contrasted to contexts of risk depending on whether we have probabilities or not. Against this view, I argue that the risk-uncertainty distinction is practically irrelevant. I start by noting that the history of the distinction between risk and uncertainty is more varied than is sometimes assumed. In order to examine the distinction, I unpack the idea of having probabilities, in particular by distinguishing three interpretations of probability: objective, epistemic, and subjective probability. I then claim that if we are concerned with whether we have probabilities at all-regardless of how low their epistemic credentials are-then we almost always have probabilities for policy-making. The reason is that subjective and epistemic probability are the relevant interpretations of probability and we almost always have subjective and epistemic probabilities. In contrast, if we are only concerned with probabilities that have sufficiently high epistemic credentials, then we obviously do not always have probabilities. Climate policy, for example, would then be a case of decision-making under uncertainty. But, so I argue, we should not dismiss probabilities with low epistemic credentials. Rather, when they are the best available probabilities our decision principles should make use of them. And, since they are almost always available, the risk-uncertainty distinction remains irrelevant.

[80 years of soial service in medicine].

PubMed

Hace 80 años, la Escuela de Medicina de la Universidad Nacional, en voz de su director, Gustavo Baz Prada, hizo una propuesta que pronto se convirtió en realidad y finalmente en norma, la que desde entonces se conoce como SS. Esta iniciativa se vio como una manera para que los estudiantes de medicina del último año retribuyeran a la sociedad una parte de lo que esta invirtió en su educación, consolidaran su formación mediante la exposición a las realidades de todos los días en los medios más necesitados, se pusieran a prueba sobre sus verdaderas capacidades para atender pacientes y participaran en la solución de un problema de atención sanitaria que en ese entonces era mucho más apremiante que ahora. Unos años después, los recién egresados de otras licenciaturas (pasantes) también fueron incorporados a esta estrategia y, al fin, se reconoció formalmente como una responsabilidad de las instituciones educativas. Las aportaciones del SS a la salud de las personas y a la formación de los médicos han sido incuestionables, y la experiencia humana que ha representado para quienes lo han vivido ha dejado marcas indelebles.

Neurobiología de la impulsividad y los trastornos de la conducta alimentaria*

PubMed Central

Orozco-Cabal, Luis Felipe; Herin, David

2009-01-01

Resumen Introducción La impulsividad es un rasgo de personalidad multidimensional relacionado con el control del comportamiento y las emociones. Está presente de manera diversa en los trastornos de la conducta alimentaria, particularmente, en la bulimia nerviosa (BN). Aunque la relación entre la impulsividad y BN ha sido objeto de numerosas investigaciones, en la actualidad se desconocen los sustratos neurobiológicos de esta relación. Objetivos Discutir críticamente la evidencia que sugiere que las alteraciones en los sistemas neuronales relacio-nados con las funciones ejecutivas, con la formación de preferencias y con la regulación de los estados emocionales sirven como base para el rasgo de personalidad impulsiva, así como su estado en subgrupos de pacientes con BN. Métodos Búsqueda selectiva de la literatura relevante. Resultados y conclusiones Esta discusión ilustra la complejidad de la relación entre la impulsividad y BN, donde la impulsividad actúa como un factor de vulnerabilidad que puede sensibilizar al sujeto con BN a estados emocionales negativos, durante los cuales modifica el impacto de estímulos internos y externos sobre el comportamiento y su regulación, favoreciendo así patrones de comportamiento maladaptativos e inflexibles. PMID:19838321

A brief introduction to probability.

PubMed

Di Paola, Gioacchino; Bertani, Alessandro; De Monte, Lavinia; Tuzzolino, Fabio

2018-02-01

The theory of probability has been debated for centuries: back in 1600, French mathematics used the rules of probability to place and win bets. Subsequently, the knowledge of probability has significantly evolved and is now an essential tool for statistics. In this paper, the basic theoretical principles of probability will be reviewed, with the aim of facilitating the comprehension of statistical inference. After a brief general introduction on probability, we will review the concept of the "probability distribution" that is a function providing the probabilities of occurrence of different possible outcomes of a categorical or continuous variable. Specific attention will be focused on normal distribution that is the most relevant distribution applied to statistical analysis.

PubMed

Hernández Mosqueira, Claudio; Hernández Vasquez, Dagoberto; Caniuqueo Vargas, Alexis; Castillo Quezada, Humberto; Fernandes Da Silva, Sandro; Pavez-Adasme, Gustavo; Martínez Salazar, Cristian; Cárcamo-Oyarzún, Jaime; Fernandes Filho, José

2016-11-29

Introducción: Chile en las últimas décadas ha experimentado un cambio en su perfil epidemiológico nutricional, pasando de una situación caracterizada por una elevada prevalencia de desnutrición y enfermedades infecciosas/parasitarias a otro completamente distinto, en donde las enfermedades crónicas y degenerativas presentan una elevada prevalencia.Objetivo: el objetivo del estudio es elaborar tablas de referencia de aspectos antropométricos y de condición física en estudiantes varones de 10 a 14 años de la ciudad de Chillán.Método: estudio descriptivo de corte transversal. La muestra se compone de 1250 varones con edades entre los 10 y 14 años. Para la confección de las tablas de referencia se utilizó estadística descriptiva y estas fueron divididas en cinco clasificaciones desde muy malo, malo, media, bueno y muy bueno, teniendo como parámetro la edad.Resultados: observamos niveles importantes de sobrepeso que se asociaron con bajo desempeño físico, lo que plantea la urgencia de realizar un seguimiento en el tiempo con herramientas de fácil aplicación como la presente batería; con el fin de detectar a tiempo a los niños que tienen bajos niveles de condición física y tomar medidas orientadas a estimular o mejorar la capacidad física como factores protectores de promoción de la salud y como ayuda en la prevención de enfermedades crónicas relacionadas con el sobrepeso u obesidad.Conclusión: en este trabajo se han establecido valores de referencia para posteriores estudios en cuanto a la condición física orientada a la salud en estudiantes varones de 10 a 14 años de la ciudad de Chillán, que permitirán evaluar e interpretar correctamente la condición física orientada a la salud de este grupo etario.

Como os Alunos do Ensino Médio da Rede Estadual de São Paulo obtém Conhecimentos Astronômicos?

NASA Astrophysics Data System (ADS)

da Cunha, W. S.; Voelzke, M. R.; Amaral, L. H.

2005-08-01

Atualmente vivencia-se um mundo globalizado onde os computadores e a internet permitiram um acesso rápido e seguro a todo tipo de informação e conhecimento. O presente trabalho visa analisar a maneira pela qual alunos de segundo grau da rede estadual da cidade de São Paulo obtiveram, caso tenham, conhecimentos básicos de astronomia quanto aos fenômenos celestes que os rodeiam, tais como a sucessão dos dias e das estações do ano, além de questioná~los sobre fatos genéricos tais como: o que vem a ser o Sol, o Big Bang, o que ocasionou a extinção dos dinossauros. Para tanto foi elaborado um formulário constando de questões de múltipla escolha, o qual foi aplicado no primeiro colegial diurno da Escola Estadual Guilherme de Almeida. Num espaço amostral de 44 alunos constatou-se que 41% dos alunos adquiriram seus conhecimentos astronômicos na escola e 59% através da mídia em geral. Neste mesmo espaço amostral apenas 11% dos alunos usaram computadores na escola, 41% na residência, 5% no trabalho e 43% não utilizaram. O presente estudo revelou também que para 50% dos alunos o professor jamais utilizou um programa de computador a respeito de astronomia ou fez alguma apresentação sobre o tema. Embora em sua fase inicial este estudo revela claramente que a maioria dos alunos não obtém na escola seus conhecimentos astronômicos, estes provém de fontes não especificamente didático-pedagógicas tais como filmes e revistas populares que não raramente geram conhecimentos incompletos e em muitos casos inclusive falhos.

Encefalitis por anticuerpos contra el receptor de NMDA: experiencia con seis pacientes pediátricos. Potencial eficacia del metotrexato

PubMed Central

Bravo-Oro, Antonio; Abud-Mendoza, Carlos; Quezada-Corona, Arturo; Dalmau, Josep; Campos-Guevara, Verónica

2016-01-01

Introducción La encefalitis por anticuerpos contra el receptor de N-metil-D-aspartato (NMDA) es una entidad cada vez más diagnosticada en edad pediátrica. A diferencia de los adultos, en muchos casos no se asocia a tumores y las manifestaciones iniciales en niños más frecuentes son crisis convulsivas y trastornos del movimiento, mientras que en los adultos predominan las alteraciones psiquiátricas. Casos clínicos Presentamos seis casos pediátricos confirmados con anticuerpos contra la subunidad NR1 del receptor de NMDA en suero y líquido cefalorraquídeo. Cinco de los casos comenzaron con crisis convulsivas como manifestación clínica inicial antes de desarrollar el cuadro clásico de esta entidad. En todos los casos se utilizaron esteroides como primera línea de tratamiento, con los que sólo se observó control de las manifestaciones en uno, por lo que el resto de los pacientes requirió inmunomoduladores de segunda línea. Todos los pacientes recibieron metotrexato como tratamiento inmunomodulador para evitar recaídas y la evolución fue a la mejoría en todos ellos. Conclusiones En nuestra serie de pacientes con encefalitis por anticuerpos contra el receptor de NMDA, ninguno se asoció a tumores. Todos los casos recibieron metotrexato por lo menos durante un año, no observamos eventos adversos clínicos ni por laboratorio, ni hubo secuelas neurológicas ni recaídas durante el tratamiento. Aunque es una serie pequeña y es deseable incrementar el número y tiempo de evolución, consideramos el metotrexato una excelente alternativa como tratamiento inmunomodulador para esta patología. PMID:24150952

PubMed

Oyarce Merino, Karina; Valladares Vega, Macarena; Elizondo-Vega, Roberto; Obregón, Ana María

2016-11-29

Introducción: cambios socioculturales como el incremento en el sedentarismo y el consumo de alimentos ricos en grasas y azúcares, sumado a características genéticas, han producido un aumento en las cifras de obesidad a nivel mundial. La evaluación temprana en niños, mediante el establecimiento de perfi les genéticos asociados a obesidad y a la regulación metabólica y hedónica de la alimentación, complementado con estudios de la conducta alimentaria, nos permitiría predecir la predisposición a la obesidad en etapas adultas.Objetivo: revisar los conceptos asociados a la conducta alimenticia, enfocándose en la regulación hedónica, que puede convertirse en un parámetro predictivo de obesidad en niños.Material y métodos: se revisó la bibliografía asociada a obesidad infantil y a la regulación homeostática y hedónica de la obesidad, como también parámetros génicos asociados a la obesidad. En la búsqueda de artículos se incluyó el trabajo en animales y humanos (adultos y niños, pero con énfasis en niños).Resultados: se analizaron los mecanismos celulares de la regulación de la ingesta, así como los estudios de conducta alimentaria en niños, entregando antecedentes y carencias en el desarrollo investigativo para la predicción de la obesidad infantil.Conclusión: la regulación hedónica de la ingesta alimenticia en niños, como perfi les genéticos asociados a receptores de dopamina, puede convertirse en un importante predictor de la obesidad. Es necesario incrementar el número de estudios que permitan defi nir de mejor forma, cuáles son los mejores parámetros para predecir el desarrollo de la obesidad adulta.

Obstáculos a la adherencia y retención en los sistemas de salud público y privado según pacientes y personal de salud

PubMed Central

Arístegui, Inés; Dorigo, Analía; Bofill, Lina; Bordatto, Alejandra; Lucas, Mar; Cabanillas, Graciela Fernández; Sued, Omar; Cahn, Pedro; Cassetti, Isabel; Weiss, Stephen; Jones., Deborah

2016-01-01

Resumen Introducción el Programa Nacional de Sida garantiza el acceso universal a los antirretrovirales, aun así las personas que reciben medicamentos a través del sistema público no logran obtener una carga viral indetectable en la misma proporción que los pacientes del sistema privado. Este estudio cualitativo tiene como objeto identificar los factores asociados a la adherencia y retención en la cascada de atención de VIH de los sistemas de salud público y privado de Buenos Aires, según las percepciones de pacientes y del personal de salud. Métodos se registraron datos cualitativos de 12 entrevistas semi-estructuradas a informantes clave y 4 grupos focales de pacientes y personal de salud tanto del sistema público como privado. Se codificaron y analizaron temas predeterminados sobre adherencia, utilizando el software QRS Nvivo9® de análisis de datos cualitativos. Resultados pacientes y personal de salud de ambos sistemas coinciden en la importancia del estigma asociado al VIH, la relación médicopaciente, la comunicación entre ambos y la división de responsabilidades en relación al tratamiento como aspectos fundamentales para la adherencia y retención en la cascada de atención. Se observan diferencias entre los sistemas en la forma en que algunos de estos aspectos actúan. Las barreras estructurales se presentan como principales obstáculos del sistema público. Discusión se resalta la necesidad de intervenciones focalizadas en la díada médico-paciente que considere las particularidades de cada sistema de atención para facilitar el compromiso del paciente en la adherencia. PMID:26878024

PubMed

Domínguez, Vanihamín; Aguiñiga, Itzen; Moreno, Leticia; Torres, Beatriz; Santiago-Osorio, Edelmiro

2017-12-01

Introducción. El caseinato de sodio, una sal de la caseína utilizada como agente proinflamatorio en ratones, es capaz de inducir granulopoyesis en vivo e incrementar la producción de citocinas esenciales en dicho evento.Objetivo. Evaluar si el caseinato de sodio es capaz de inducir un efecto biológico en células de origen linfoide y la producción de citocinas involucradas con este linaje.Materiales y métodos: Se utilizaron ratones hembra BALB/c de 8 a 12 semanas de edad. Los animales se inyectaron cuatro veces, con intervalos de 48 horas, por vía intraperitoneal con 1 ml de caseinato de sodio (10 % de SFB p/v). La población de linfocitos B y la incorporación de bromodesoxiuridina (BrdU) se analizaron mediante citometría de flujo. La detección de la interleucina 7 se evaluó mediante la técnica de ELISA.Resultados. Tras la inyección por vía intraperitoneal, el número de linfocitos B 220+ provenientes del bazo de ratones tratados con caseinato de sodio aumentó comparados con los que solo recibieron el vehículo como tratamiento (89,01±1,03 Vs. 75,66±2,08), así como la incorporación de BrdU en células B220+ (38,59±4,48 Vs. 11,82±1,04). Se evidenció, asimismo, el incremento en la concentración de la interleucina 7 (IL-7) en el suero de los ratones tratados con caseinato de sodio, comparados con los que solo recibieron el vehículo (62,1±17,5 Vs. 26,9±4,4 pg/ml).Conclusión. El caseinato de sodio fue capaz de aumentar el número de linfocitos B en bazo de ratones, así como inducir la producción de IL-7, citocina clave para la linfopoyesis B.

Prevalence of previously undiagnosed abdominal aortic aneurysms in the area of Como: the ComoCuore "looking for AAA" ultrasonography screening.

PubMed

Corrado, Giovanni; Durante, Alessandro; Genchi, Vincenzo; Trabattoni, Loris; Beretta, Sandro; Rovelli, Enza; Foglia-Manzillo, Giovanni; Ferrari, Giovanni

2016-08-01

The prognosis for abdominal aortic aneurysm (AAA) rupture is poor. Long-term follow-up of population-based randomized trials has demonstrated that ultrasound (US) screening for abdominal aortic aneurysms (AAAs) measuring 3 cm or greater decreases AAA-related mortality rates and is cost-effective. We though to prospectively perform during a 26-month period a limited US examination of the infrarenal aorta in volunteers of both gender aged 60-85 years without history of AAA living in the area of Como, Italy. From September 2010 to November 2013 ComoCuore, a no-profit nongovernmental association, enrolled 1555 people (aged 68.8 ± 6.8 years; 48.6 % males). Clinical data and a US imaging of the aorta were collected for each participant. AAA was found in 22 volunteers (1.4 %) mainly males (2.5 % in males vs. 0.4 % in females p = 0.005). Overall, the prevalence of cardiovascular risk factors was higher in patients with vs. without AAA (mean 2.9 ± 3.0 vs. 1.4 ± 1.0 respectively, p < 0.0001). Independent predictors of AAA on multivariate analysis were age (OR 1.14, 1.06-1.22; p < 0.0001), male gender (OR 8.23, 1.79-37.91; p = 0.007), and both current (OR 4.98, 1.57-15.79; p = 0.007) and previous smoking (OR 2.76, 1.12-8.94; p = 0.03). Our study confirms the feasibility of one time US screening for AAA in a large cohort of asymptomatic people. Independent predictors of AAA were male sex, older age and a history of smoking. Accordingly to recent data the prevalence of AAA seems to be declining, maybe due to a reduction of smoking in Italy.

Abundâncias químicas de estrelas T Tauri fracas

NASA Astrophysics Data System (ADS)

Rojas, G. A.; Gregorio-Hetem, J.

2003-08-01

Apresentamos resultados do estudo de 44 estrelas pré-seqüência principal, para as quais buscamos realizar uma classificação espectroscópica e determinar parâmetros estelares e abundâncias químicas. A amostra foi escolhida da seguinte maneira : 21 objetos selecionados a partir de catálogos de objetos jovens, como o Pico dos Dias Survey e o Herbig Bell Catalogue, e 23 objetos selecionados a partir de contrapartidas ópticas de fontes de raios X detectadas pelo satélite ROSAT. Dentre 24 objetos previamente classificados como estrelas T Tauri Fracas, apenas 7 revelaram ser realmente pertencentes à essa classe, sendo os demais objetos T Tauri Clássicas ou estrelas evoluídas da pré-seqüência principal. Esse resultado demonstra que o critério mais utilizado para distinguir as T Tauri Clássicas das T Tauri Fracas, baseado na largura equivelente da emissão Ha, não é suficiente para determinar o estágio evolutivo desses objetos. Para o cálculo de parâmetros estelares e abundâncias, foram escolhidas as estrelas que apresentam características ideais para esse tipo de estudo, como ausência de velamento, baixa velocidade de rotação e espectros com razão sinal-ruído adequada. Os parâmetros estelares como temperatura efetiva e gravidade foram determinados através do equilíbrio de excitação e ionização das linhas de Ferro, e as abundâncias químicas foram calculadas utilizando o método de síntese espectral. Serão apresentados os parâmetros estelares e as abundâncias de Lítio para toda a amostra, e abundâncias de vários elementos quimicos para 7 estrelas estudadas em maior detalhe

Naive Probability: A Mental Model Theory of Extensional Reasoning.

ERIC Educational Resources Information Center

Johnson-Laird, P. N.; Legrenzi, Paolo; Girotto, Vittorio; Legrenzi, Maria Sonino; Caverni, Jean-Paul

1999-01-01

Outlines a theory of naive probability in which individuals who are unfamiliar with the probability calculus can infer the probabilities of events in an "extensional" way. The theory accommodates reasoning based on numerical premises, and explains how naive reasoners can infer posterior probabilities without relying on Bayes's theorem.…

The Estimation of Tree Posterior Probabilities Using Conditional Clade Probability Distributions

PubMed Central

Larget, Bret

2013-01-01

In this article I introduce the idea of conditional independence of separated subtrees as a principle by which to estimate the posterior probability of trees using conditional clade probability distributions rather than simple sample relative frequencies. I describe an algorithm for these calculations and software which implements these ideas. I show that these alternative calculations are very similar to simple sample relative frequencies for high probability trees but are substantially more accurate for relatively low probability trees. The method allows the posterior probability of unsampled trees to be calculated when these trees contain only clades that are in other sampled trees. Furthermore, the method can be used to estimate the total probability of the set of sampled trees which provides a measure of the thoroughness of a posterior sample. [Bayesian phylogenetics; conditional clade distributions; improved accuracy; posterior probabilities of trees.] PMID:23479066

Prospect evaluation as a function of numeracy and probability denominator.

PubMed

Millroth, Philip; Juslin, Peter

2015-05-01

This study examines how numeracy and probability denominator (a direct-ratio probability, a relative frequency with denominator 100, a relative frequency with denominator 10,000) affect the evaluation of prospects in an expected-value based pricing task. We expected that numeracy would affect the results due to differences in the linearity of number perception and the susceptibility to denominator neglect with different probability formats. An analysis with functional measurement verified that participants integrated value and probability into an expected value. However, a significant interaction between numeracy and probability format and subsequent analyses of the parameters of cumulative prospect theory showed that the manipulation of probability denominator changed participants' psychophysical response to probability and value. Standard methods in decision research may thus confound people's genuine risk attitude with their numerical capacities and the probability format used. Copyright © 2015 Elsevier B.V. All rights reserved.

Estimating the concordance probability in a survival analysis with a discrete number of risk groups.

PubMed

Heller, Glenn; Mo, Qianxing

2016-04-01

A clinical risk classification system is an important component of a treatment decision algorithm. A measure used to assess the strength of a risk classification system is discrimination, and when the outcome is survival time, the most commonly applied global measure of discrimination is the concordance probability. The concordance probability represents the pairwise probability of lower patient risk given longer survival time. The c-index and the concordance probability estimate have been used to estimate the concordance probability when patient-specific risk scores are continuous. In the current paper, the concordance probability estimate and an inverse probability censoring weighted c-index are modified to account for discrete risk scores. Simulations are generated to assess the finite sample properties of the concordance probability estimate and the weighted c-index. An application of these measures of discriminatory power to a metastatic prostate cancer risk classification system is examined.

Factors influencing reporting and harvest probabilities in North American geese

USGS Publications Warehouse

Zimmerman, G.S.; Moser, T.J.; Kendall, W.L.; Doherty, P.F.; White, Gary C.; Caswell, D.F.

2009-01-01

We assessed variation in reporting probabilities of standard bands among species, populations, harvest locations, and size classes of North American geese to enable estimation of unbiased harvest probabilities. We included reward (US10,20,30,50, or100) and control (0) banded geese from 16 recognized goose populations of 4 species: Canada (Branta canadensis), cackling (B. hutchinsii), Ross's (Chen rossii), and snow geese (C. caerulescens). We incorporated spatially explicit direct recoveries and live recaptures into a multinomial model to estimate reporting, harvest, and band-retention probabilities. We compared various models for estimating harvest probabilities at country (United States vs. Canada), flyway (5 administrative regions), and harvest area (i.e., flyways divided into northern and southern sections) scales. Mean reporting probability of standard bands was 0.73 (95 CI 0.690.77). Point estimates of reporting probabilities for goose populations or spatial units varied from 0.52 to 0.93, but confidence intervals for individual estimates overlapped and model selection indicated that models with species, population, or spatial effects were less parsimonious than those without these effects. Our estimates were similar to recently reported estimates for mallards (Anas platyrhynchos). We provide current harvest probability estimates for these populations using our direct measures of reporting probability, improving the accuracy of previous estimates obtained from recovery probabilities alone. Goose managers and researchers throughout North America can use our reporting probabilities to correct recovery probabilities estimated from standard banding operations for deriving spatially explicit harvest probabilities.

Organization of professional practices against intrafamily violence against children and adolescents in the institutional context.

PubMed

Schek, Gabriele; Silva, Mara Regina Santos da; Lacharité, Carl; Bueno, Maria Emília Nunes

2017-06-05

to analyze based on the practitioners' discourse, the way they organize their practices confronting situations of intra-family violence against children and adolescents. qualitative research carried out with 15 professionals who work in social and health services located in the southernmost of Brazil. Data were collected through semi-structured interviews, performed at the participants' workplace. We used a theoretical matrix to analyze the data, based on Institutional Ethnography and the technique of discursive textual analysis. the practitioners' practices developed in situations of intra-family violence against children and adolescents are organized on the basis of: power relations that take place in services that respond to violence situations; routines instituted to meet the demands of care in services; and the interplay between the conception of violence as a public health problem and the conception of violence as a social problem. the way these practices are organized is reflected in actions that are not protective against situations of intra-family violence against children and adolescents. analisar, com base no discurso dos profissionais, como ocorre a organização de suas práticas frente às situações de violência intrafamiliar contra crianças e adolescentes. pesquisa qualitativa, realizada com 15 profissionais que atuam em serviços sociais e de saúde localizados no extremo sul do Brasil. Os dados foram coletados por meio de entrevistas semiestruturadas, realizadas no próprio local de trabalho dos participantes. Para a análise dos dados foi construída uma matriz teórica com base na Etnografia Institucional e utilizada a técnica de análise textual discursiva. as práticas profissionais desenvolvidas nas situações de violência intrafamiliar contra crianças e adolescentes se organizam a partir de: relações de poder que se desenrolam nos serviços que atendem às situações de violência; rotinas instituídas para suprir as demandas de atendimento nos serviços e o inter-jogo entre a concepção de violência como um problema de saúde pública e a de violência como um problema social. a maneira como essas práticas estão organizadas se reflete em ações pouco protetivas frente às situações de violência intrafamiliar contra crianças e adolescentes. analizar, basado en el discurso profesional, como ocurre la organización de sus prácticas frente a las situaciones de violencia doméstica intrafamiliar contra niños y adolescentes. investigación cualitativa realizada con 15 profesionales que trabajan en salud y servicios sociales en el sur de Brasil. Los datos fueron recolectados a través de entrevistas semiestructuradas realizadas en el lugar de trabajo de los participantes. Para el análisis de los datos se construyó una matriz teórica basada en la Etnografia Institucional y utilizada la técnica de análisis textual del discurso. las prácticas profesionales desarrolladas en situaciones de violencia intrafamiliar contra los niños y adolescentes se organizan a partir de: las relaciones de poder que tienen lugar en los servicios que responden a las situaciones de violencia; las rutinas puestas en practica para satisfacer las demandas de servicios de atención y el inter-juego entre la concepción de la violencia como un problema de salud pública y la violencia como un problema social. la forma en que estas prácticas se organizan se refleja en acciones de poca protección en el enfrentamiento de las situaciones de violencia intrafamiliar contra niños y adolescentes.

PFI-ZEKE (Pulsed Field Ionization-Zero Electron Kinetic Energy) para el estudio de iones

NASA Astrophysics Data System (ADS)

Castaño, F.; Fernández, J. A.; Basterretxea, A. Longarte. F.; Sánchez Rayo, M. N.; Martínez, R.

Entre las áreas hacia donde ha evolucionado la Química en los últimos años están los estudios de sistemas con especies reactivas de alta energía y los dominados por fuerzas intermoleculares débiles, con energías de unas pocas kcal/mol. En efecto, el estudio de las propiedades de los iones, comenzando por su relación con la molécula neutra de la que procede, la energía de ionización, los estados vibracionales y rotacionales, energías de enlace de Van der Waals entre el ión y una amplia variedad de otras moléculas, sus confórmeros o isómeros y sus reacciones o semi-reacciones químicas están en la raíz de la necesidad de la espectroscopía conocida como PFI-ZEKE, Pulsed Field Ionization-Zero Electron Kinetic Energy. Entre las aplicaciones que requieren estos conocimientos se encuentran la generación de plasmas para la fabricación de semiconductores, memorias magnéticas, etc, así como los sistemas astrofísicos, la ionosfera terrestre, etc. La espectroscopía ZEKE es una evolución de las de fluorescencia inducida por láser, LIF, ionización multifotónica acrecentada por resonancia, REMPI, con uno y dos colores y acoplada a un sistema de tiempo de vuelo, REMPI-TOF-MS, y las espectroscopías de doble resonancia IR-UV y UV-UV. Sus espectros y la ayuda de cálculos ab inicio permite determinar las energías de enlace de complejos de van der Waals en estados fundamental y excitados, identificar confórmeros e isómeros, obtener energías de ionización experimentales aproximadas (100 cm-1) y otras variables de interés. Al igual que con LIF, REMPI y dobles resonancias, es posible utilizar muestras gaseosas, pero los espectros están muy saturados de bandas y su interpretación es difícil o imposible. Se evitan estas dificultades estudiando las moléculas o complejos en expansiones supersónicas, donde la T de los grados de libertad solo alcanzan unos pocos K. Para realizar experimentos de ZEKE hay que utilizar una propiedad recientemente descubierta, que va en contra de lo esperado en otros sistemas físicos y que consiste en que los altos estados Rydberg de átomos, moléculas y sus complejos de van der Waals (o de los iones) tienen tiempos de vida de centenas de μ s. En resumen, el experimento y la espectroscopía ZEKE consiste en excitar un átomo, molécula o cluster sucesivamente a dos estados excitados selectivos de manera que el final sea un estado Rydberg. A continuación se aplica un campo eléctrico variable que lo ioniza y después de un cierto retraso se aplica un campo eléctrico de extracción, tanto para el electrón como para el ión. El espectro de los iones, es un espectro ZEKE. Hay varias alternativas para hacer este último proceso. El estudio de la espectroscopía y propiedades de iones y sus clusters requiere el conocimiento detallado de la espectroscopía de la molécula neutra, los estados Rydberg, de los confórmeros y sus complejos. Todo ello implica el haber estudiado los sistemas por LIF, REMPI y doble resonancia (hole burning IR-UV, UV-UV). Además solo es posible interpretar los resultados y obtener la información contenida en los espectros con ayuda de cálculos cuánticos ab initio. Hasta el momento hemos aplicado tanto el ZEKE como el conjunto de técnicas mencionadas anteriormente, a varias molécula de interés químico general como anilina y sus derivados, así como sus complejos con agua y amoniaco. Sin embargo, el método es muy versátil y puede aplicarse a iones de átomos, iones múltiples, moléculas sencillas y sus clusters así como a sus semi-reacciones. Como ejemplo de uno de estos espectros PFI-ZEKE se presenta aquí el caso del amonibenzonitrilo, ABN y solamente en su estado fundamental. En la conferencia se presentarán espectros ZEKE del ABN y moléculas similares en estados vibracionales intermedios (islas de estabilidad), así como la determinación de potenciales de ionización precisos, energías de enlace de compuestos del ión con varios disolventes y otras propiedades de interés, discutiendo sus resultados.

UQ for Decision Making: How (at least five) Kinds of Probability Might Come Into Play

NASA Astrophysics Data System (ADS)

Smith, L. A.

2013-12-01

In 1959 IJ Good published the discussion "Kinds of Probability" in Science. Good identified (at least) five kinds. The need for (at least) a sixth kind of probability when quantifying uncertainty in the context of climate science is discussed. This discussion brings out the differences in weather-like forecasting tasks and climate-links tasks, with a focus on the effective use both of science and of modelling in support of decision making. Good also introduced the idea of a "Dynamic probability" a probability one expects to change without any additional empirical evidence; the probabilities assigned by a chess playing program when it is only half thorough its analysis being an example. This case is contrasted with the case of "Mature probabilities" where a forecast algorithm (or model) has converged on its asymptotic probabilities and the question hinges in whether or not those probabilities are expected to change significantly before the event in question occurs, even in the absence of new empirical evidence. If so, then how might one report and deploy such immature probabilities in scientific-support of decision-making rationally? Mature Probability is suggested as a useful sixth kind, although Good would doubtlessly argue that we can get by with just one, effective communication with decision makers may be enhanced by speaking as if the others existed. This again highlights the distinction between weather-like contexts and climate-like contexts. In the former context one has access to a relevant climatology (a relevant, arguably informative distribution prior to any model simulations), in the latter context that information is not available although one can fall back on the scientific basis upon which the model itself rests, and estimate the probability that the model output is in fact misinformative. This subjective "probability of a big surprise" is one way to communicate the probability of model-based information holding in practice, the probability that the information the model-based probability is conditioned on holds. It is argued that no model-based climate-like probability forecast is complete without a quantitative estimate of its own irrelevance, and that the clear identification of model-based probability forecasts as mature or immature, are critical elements for maintaining the credibility of science-based decision support, and can shape uncertainty quantification more widely.

[Not Available].

PubMed

Fort Casamartina, Eduard; Arribas Hortiguela, Lorena; Bleda Pérez, Carmen; Muñoz Sánchez, Carme; Peiro Martínez, Imma; Perayre Badía, María; Clopés Estela, Ana

2016-06-03

Durante la última década, el conocimiento de nuevos mecanismos implicados en el desarrollo del cáncer ha permitido el diseño de nuevos fármacos para su tratamiento y la mayor parte de ellos son fármacos que se administran por vía oral. Uno de los principales problemas de los pacientes oncohematológicos es la desnutrición, que suele tener causas multifactoriales (de la propia enfermedad, de los pacientes y de los diferentes tratamientos administrados). Para minimizar el impacto de la desnutrición es necesaria una intervención nutricional, ya sea adaptando la dieta o mediante la instauración de soporte nutricional artificial, en función de la gravedad de cada caso. En cualquier paciente que esté recibiendo un tratamiento oncológico hay que evaluar las posibles interacciones que pueden existir con el soporte nutricional instaurado, ya sea dieta oral, suplementación oral o nutrición enteral. Estas interacciones pueden disminuir la eficacia, aumentar la toxicidad de los tratamientos o producir déficits nutricionales. Se detallan las principales interacciones que se pueden producir, las interacciones entre los tratamientos oncológicos y el soporte nutricional.

[Scabies and the significance of "suriones" in the handwritten manuscripts of Hildegard von Bingen].

PubMed

Riethe, Peter

2006-01-01

In her studies on nature and medicine, the "Liber simplicis medicinae" (LSM or "Physica") and the "Liber compositae medicinae" (LCM or "Causae et Curae"), Hildegard von Bingen mentions Scabies (mange) in several passages. She characterizes "suren aut (= or) sneuelzen" as the cause of the disease, which she calls also "gracillimi vermiculi", that is, tiny worms that burrow into the human skin ("ubi suren aut sneuelzen hominem comedendo ledunt"). In this context the meanings of the German-ancestor terms "suren aut sneuelzen", which are found in the Latin text concerning the "Alia Mynza", are still disputed. The question whether Hildegard knew the cause of scabies the author discusses on the basis of ancient and medieval sources as well as modem medical historical and philological/linguistic research approaches. He concludes that Hildegard was able not only to describe the symptoms exactly, but also to define the cause of the disease as a special parasite. Consequently, she differentiates other diseases of the skin, such as "grint", from scabies. The proposed interpretation of "sneuelzen" as the tick is untenable. The assumption that both terms are synonyms for sarcoptes scabiei can be confirmed by philological and medical historical research.

Ganglioneuroblastoma: Case report and review of the literature.

PubMed

Alessi, S; Grignani, M; Carone, L

2011-06-01

Neuroblastoma are among the most important tumors of extracranial origin in pediatric patients. They arise from embryonal cells involved in the development of the sympathetic nervous system, whose differentiation has been arrested [1,2]. They are the tumors most frequently diagnosed during the first decade of life. Their evolution is unpredictable, ranging from progression to spontaneous regression or maturation, and their location and metastatic potential vary. Little is known about the cause of these tumors and the risk factors associated with their development. This article describes a typical case of ganglioneuroblastoma and provides a review of the literature on this type of tumor.Sommario Il neuroblastoma è uno dei più importanti tumori pediatrici di derivazione extracranica; esso origina dalle cellule embrionali coinvolte nello sviluppo del sistema nervoso simpatico a causa di un blocco nel loro processo di differenziamento [1,2]. È la più frequente neoplasia della prima decade di vita; la sua progressione biologica è imprevedibile, regressione spontanea, maturazione a ganglioneuroma, localizzazione e metastatizzazione variabili. Poco è noto a riguardo dei fattori di rischio e della sua eziopatogenesi. Viene presentato un caso tipico di ganglioneuroblastoma e riesaminata la letteratura su questa neoplasia.

Synchronization Analysis of Master-Slave Probabilistic Boolean Networks.

PubMed

Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W C; Cao, Jinde

2015-08-28

In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results.

Synchronization Analysis of Master-Slave Probabilistic Boolean Networks

PubMed Central

Lu, Jianquan; Zhong, Jie; Li, Lulu; Ho, Daniel W. C.; Cao, Jinde

2015-01-01

In this paper, we analyze the synchronization problem of master-slave probabilistic Boolean networks (PBNs). The master Boolean network (BN) is a deterministic BN, while the slave BN is determined by a series of possible logical functions with certain probability at each discrete time point. In this paper, we firstly define the synchronization of master-slave PBNs with probability one, and then we investigate synchronization with probability one. By resorting to new approach called semi-tensor product (STP), the master-slave PBNs are expressed in equivalent algebraic forms. Based on the algebraic form, some necessary and sufficient criteria are derived to guarantee synchronization with probability one. Further, we study the synchronization of master-slave PBNs in probability. Synchronization in probability implies that for any initial states, the master BN can be synchronized by the slave BN with certain probability, while synchronization with probability one implies that master BN can be synchronized by the slave BN with probability one. Based on the equivalent algebraic form, some efficient conditions are derived to guarantee synchronization in probability. Finally, several numerical examples are presented to show the effectiveness of the main results. PMID:26315380

Tal Como Somos/Just As We Are: An Educational Film to Reduce Stigma towards Gay and Bisexual Men, Transgender Individuals & Persons Living with HIV/AIDS

PubMed Central

Ramirez-Valles, Jesus; Kuhns, Lisa M.; Manjarrez, Dianna

2013-01-01

In this paper we describe the development and dissemination of a film-based educational intervention to reduce negative attitudes towards gay and bisexual men and transgender women (GBT) and people living with HIV/AIDS (PLWHA) in Latino communities, with a focus on youth. The intervention, Tal Como Somos/Just as We Are, is based on stigma and attribution theories, extensive formative research, and community input. Evaluation findings among educators and school youth suggest the film has the potential to effectively impact attitudes towards GBT and PLWHA. The film and intervention are being disseminated using diffusion of innovations theory through community-based organizations, schools, television broadcasting and film festivals. PMID:24377496

Estructura orbital en el Problema Restringido Rectilíneo Isósceles

NASA Astrophysics Data System (ADS)

Orellana, R. B.

Para definir problemas en Mecánica Celeste se utilizan diferentes parámetros. El conocimiento de la dinámica del problema para valores particulares de estos parámetros nos permite entender el comportamiento en casos más generales. El Problema Restringido Rectilíneo Isósceles puede ser considerado como el caso límite del Problema de Sitnikov cuando la excentricidad tiende a uno o como el Problema Isósceles cuando la masa central tiende a cero. Se ha compactificado el espacio de fases y analizado la dinámica en el límite. Esto ha permitido separar el espacio de fases en diferentes regiones dependiendo de las clases de órbitas.

Como Lo Hago Yo: Myelomeningocele

PubMed Central

Lazareff, Jorge

2014-01-01

Fortificación con ádico fólico es efectiva, pero aún falta conciencia en los jóvenes. La legalidad del aborto aumenta la importancia de la consulta prenatal. Realizo la cirugía bajo microcoscopio por razones didácticas. Irrigación continua para reducir la temperatura del tejido. Trato a la plaqueta como tejido viable. No suturo la plaqueta. No cierro músculo. ATB por una semana después de cirugía. Hidrocefalia: Válvula en todos los casos de ventriculomegalia. Médula anclada: Desanclar una sola vez. Chiari II: Revisar la válvula. Incluir en el seguimiento rendimiento escolar, puede indicar obstrucción de la válvula o médula anclada. PMID:24791217

From Rome to Como: 20 years of active research on carbon-based electrodes for lithium batteries at INP-Grenoble

NASA Astrophysics Data System (ADS)

Yazami, Rachid

This paper reviews the main areas of research performed at different Laboratories of the Institut National Polytechnique de Grenoble (INPG) over the past 20 years, specifically on cabonaceous materials for electrode applications in lithium batteries. The most significant event was the discovery in the early 1980s of reversible lithium intercalation into graphite in polymer electrolytes, which led to the use of this material in today's lithium-ion batteries. Important work was also carried out on positive electrode for primary and secondary batteries, especially graphite oxide and graphite fluoride. Most of these results were presented at the 10 IMLB series Symposia, which started in Rome in 1982 and were back to Como, Italy, in 2000.

Low temperature growth of ultra-high mass density carbon nanotube forests on conductive supports

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

Sugime, Hisashi; Esconjauregui, Santiago; Yang, Junwei

2013-08-12

We grow ultra-high mass density carbon nanotube forests at 450 °C on Ti-coated Cu supports using Co-Mo co-catalyst. X-ray photoelectron spectroscopy shows Mo strongly interacts with Ti and Co, suppressing both aggregation and lifting off of Co particles and, thus, promoting the root growth mechanism. The forests average a height of 0.38 μm and a mass density of 1.6 g cm{sup −3}. This mass density is the highest reported so far, even at higher temperatures or on insulators. The forests and Cu supports show ohmic conductivity (lowest resistance ∼22 kΩ), suggesting Co-Mo is useful for applications requiring forest growth onmore » conductors.« less

The estimation of tree posterior probabilities using conditional clade probability distributions.

PubMed

Larget, Bret

2013-07-01

In this article I introduce the idea of conditional independence of separated subtrees as a principle by which to estimate the posterior probability of trees using conditional clade probability distributions rather than simple sample relative frequencies. I describe an algorithm for these calculations and software which implements these ideas. I show that these alternative calculations are very similar to simple sample relative frequencies for high probability trees but are substantially more accurate for relatively low probability trees. The method allows the posterior probability of unsampled trees to be calculated when these trees contain only clades that are in other sampled trees. Furthermore, the method can be used to estimate the total probability of the set of sampled trees which provides a measure of the thoroughness of a posterior sample.

Study on conditional probability of surface rupture: effect of fault dip and width of seismogenic layer

NASA Astrophysics Data System (ADS)

Inoue, N.

2017-12-01

The conditional probability of surface ruptures is affected by various factors, such as shallow material properties, process of earthquakes, ground motions and so on. Toda (2013) pointed out difference of the conditional probability of strike and reverse fault by considering the fault dip and width of seismogenic layer. This study evaluated conditional probability of surface rupture based on following procedures. Fault geometry was determined from the randomly generated magnitude based on The Headquarters for Earthquake Research Promotion (2017) method. If the defined fault plane was not saturated in the assumed width of the seismogenic layer, the fault plane depth was randomly provided within the seismogenic layer. The logistic analysis was performed to two data sets: surface displacement calculated by dislocation methods (Wang et al., 2003) from the defined source fault, the depth of top of the defined source fault. The estimated conditional probability from surface displacement indicated higher probability of reverse faults than that of strike faults, and this result coincides to previous similar studies (i.e. Kagawa et al., 2004; Kataoka and Kusakabe, 2005). On the contrary, the probability estimated from the depth of the source fault indicated higher probability of thrust faults than that of strike and reverse faults, and this trend is similar to the conditional probability of PFDHA results (Youngs et al., 2003; Moss and Ross, 2011). The probability of combined simulated results of thrust and reverse also shows low probability. The worldwide compiled reverse fault data include low fault dip angle earthquake. On the other hand, in the case of Japanese reverse fault, there is possibility that the conditional probability of reverse faults with less low dip angle earthquake shows low probability and indicates similar probability of strike fault (i.e. Takao et al., 2013). In the future, numerical simulation by considering failure condition of surface by the source fault would be performed in order to examine the amount of the displacement and conditional probability quantitatively.

Probability 1/e

ERIC Educational Resources Information Center

Koo, Reginald; Jones, Martin L.

2011-01-01

Quite a number of interesting problems in probability feature an event with probability equal to 1/e. This article discusses three such problems and attempts to explain why this probability occurs with such frequency.

Evaluating Perceived Probability of Threat-Relevant Outcomes and Temporal Orientation in Flying Phobia.

PubMed

Mavromoustakos, Elena; Clark, Gavin I; Rock, Adam J

2016-01-01

Probability bias regarding threat-relevant outcomes has been demonstrated across anxiety disorders but has not been investigated in flying phobia. Individual temporal orientation (time perspective) may be hypothesised to influence estimates of negative outcomes occurring. The present study investigated whether probability bias could be demonstrated in flying phobia and whether probability estimates of negative flying events was predicted by time perspective. Sixty flying phobic and fifty-five non-flying-phobic adults were recruited to complete an online questionnaire. Participants completed the Flight Anxiety Scale, Probability Scale (measuring perceived probability of flying-negative events, general-negative and general positive events) and the Past-Negative, Future and Present-Hedonistic subscales of the Zimbardo Time Perspective Inventory (variables argued to predict mental travel forward and backward in time). The flying phobic group estimated the probability of flying negative and general negative events occurring as significantly higher than non-flying phobics. Past-Negative scores (positively) and Present-Hedonistic scores (negatively) predicted probability estimates of flying negative events. The Future Orientation subscale did not significantly predict probability estimates. This study is the first to demonstrate probability bias for threat-relevant outcomes in flying phobia. Results suggest that time perspective may influence perceived probability of threat-relevant outcomes but the nature of this relationship remains to be determined.

Evaluating Perceived Probability of Threat-Relevant Outcomes and Temporal Orientation in Flying Phobia

PubMed Central

Mavromoustakos, Elena; Clark, Gavin I.; Rock, Adam J.

2016-01-01

Probability bias regarding threat-relevant outcomes has been demonstrated across anxiety disorders but has not been investigated in flying phobia. Individual temporal orientation (time perspective) may be hypothesised to influence estimates of negative outcomes occurring. The present study investigated whether probability bias could be demonstrated in flying phobia and whether probability estimates of negative flying events was predicted by time perspective. Sixty flying phobic and fifty-five non-flying-phobic adults were recruited to complete an online questionnaire. Participants completed the Flight Anxiety Scale, Probability Scale (measuring perceived probability of flying-negative events, general-negative and general positive events) and the Past-Negative, Future and Present-Hedonistic subscales of the Zimbardo Time Perspective Inventory (variables argued to predict mental travel forward and backward in time). The flying phobic group estimated the probability of flying negative and general negative events occurring as significantly higher than non-flying phobics. Past-Negative scores (positively) and Present-Hedonistic scores (negatively) predicted probability estimates of flying negative events. The Future Orientation subscale did not significantly predict probability estimates. This study is the first to demonstrate probability bias for threat-relevant outcomes in flying phobia. Results suggest that time perspective may influence perceived probability of threat-relevant outcomes but the nature of this relationship remains to be determined. PMID:27557054

Probability sampling in legal cases: Kansas cellphone users

NASA Astrophysics Data System (ADS)

Kadane, Joseph B.

2012-10-01

Probability sampling is a standard statistical technique. This article introduces the basic ideas of probability sampling, and shows in detail how probability sampling was used in a particular legal case.

[Biometric bases: basic concepts of probability calculation].

PubMed

Dinya, E

1998-04-26

The author gives or outline of the basic concepts of probability theory. The bases of the event algebra, definition of the probability, the classical probability model and the random variable are presented.

Public attitudes toward stuttering in Turkey: probability versus convenience sampling.

PubMed

Ozdemir, R Sertan; St Louis, Kenneth O; Topbaş, Seyhun

2011-12-01

A Turkish translation of the Public Opinion Survey of Human Attributes-Stuttering (POSHA-S) was used to compare probability versus convenience sampling to measure public attitudes toward stuttering. A convenience sample of adults in Eskişehir, Turkey was compared with two replicates of a school-based, probability cluster sampling scheme. The two replicates of the probability sampling scheme yielded similar demographic samples, both of which were different from the convenience sample. Components of subscores on the POSHA-S were significantly different in more than half of the comparisons between convenience and probability samples, indicating important differences in public attitudes. If POSHA-S users intend to generalize to specific geographic areas, results of this study indicate that probability sampling is a better research strategy than convenience sampling. The reader will be able to: (1) discuss the difference between convenience sampling and probability sampling; (2) describe a school-based probability sampling scheme; and (3) describe differences in POSHA-S results from convenience sampling versus probability sampling. Copyright © 2011 Elsevier Inc. All rights reserved.

On Probability Domains IV

NASA Astrophysics Data System (ADS)

Frič, Roman; Papčo, Martin

2017-12-01

Stressing a categorical approach, we continue our study of fuzzified domains of probability, in which classical random events are replaced by measurable fuzzy random events. In operational probability theory (S. Bugajski) classical random variables are replaced by statistical maps (generalized distribution maps induced by random variables) and in fuzzy probability theory (S. Gudder) the central role is played by observables (maps between probability domains). We show that to each of the two generalized probability theories there corresponds a suitable category and the two resulting categories are dually equivalent. Statistical maps and observables become morphisms. A statistical map can send a degenerated (pure) state to a non-degenerated one —a quantum phenomenon and, dually, an observable can map a crisp random event to a genuine fuzzy random event —a fuzzy phenomenon. The dual equivalence means that the operational probability theory and the fuzzy probability theory coincide and the resulting generalized probability theory has two dual aspects: quantum and fuzzy. We close with some notes on products and coproducts in the dual categories.

Climate sensitivity estimated from temperature reconstructions of the Last Glacial Maximum

NASA Astrophysics Data System (ADS)

Schmittner, A.; Urban, N.; Shakun, J. D.; Mahowald, N. M.; Clark, P. U.; Bartlein, P. J.; Mix, A. C.; Rosell-Melé, A.

2011-12-01

In 1959 IJ Good published the discussion "Kinds of Probability" in Science. Good identified (at least) five kinds. The need for (at least) a sixth kind of probability when quantifying uncertainty in the context of climate science is discussed. This discussion brings out the differences in weather-like forecasting tasks and climate-links tasks, with a focus on the effective use both of science and of modelling in support of decision making. Good also introduced the idea of a "Dynamic probability" a probability one expects to change without any additional empirical evidence; the probabilities assigned by a chess playing program when it is only half thorough its analysis being an example. This case is contrasted with the case of "Mature probabilities" where a forecast algorithm (or model) has converged on its asymptotic probabilities and the question hinges in whether or not those probabilities are expected to change significantly before the event in question occurs, even in the absence of new empirical evidence. If so, then how might one report and deploy such immature probabilities in scientific-support of decision-making rationally? Mature Probability is suggested as a useful sixth kind, although Good would doubtlessly argue that we can get by with just one, effective communication with decision makers may be enhanced by speaking as if the others existed. This again highlights the distinction between weather-like contexts and climate-like contexts. In the former context one has access to a relevant climatology (a relevant, arguably informative distribution prior to any model simulations), in the latter context that information is not available although one can fall back on the scientific basis upon which the model itself rests, and estimate the probability that the model output is in fact misinformative. This subjective "probability of a big surprise" is one way to communicate the probability of model-based information holding in practice, the probability that the information the model-based probability is conditioned on holds. It is argued that no model-based climate-like probability forecast is complete without a quantitative estimate of its own irrelevance, and that the clear identification of model-based probability forecasts as mature or immature, are critical elements for maintaining the credibility of science-based decision support, and can shape uncertainty quantification more widely.

Posttraumatic stress disorder, depression, and alcohol and tobacco use in public health workers after the 2004 Florida hurricanes.

PubMed

Fullerton, Carol S; McKibben, Jodi B A; Reissman, Dori B; Scharf, Ted; Kowalski-Trakofler, Kathleen M; Shultz, James M; Ursano, Robert J

2013-02-01

We examined the relationship of probable posttraumatic stress disorder (PTSD), probable depression, and increased alcohol and/or tobacco use to disaster exposure and work demand in Florida Department of Health workers after the 2004 hurricanes. Participants (N = 2249) completed electronic questionnaires assessing PTSD, depression, alcohol and tobacco use, hurricane exposure, and work demand. Total mental and behavioral health burden (probable PTSD, probable depression, increased alcohol and/or tobacco use) was 11%. More than 4% had probable PTSD, and 3.8% had probable depression. Among those with probable PTSD, 29.2% had increased alcohol use, and 50% had increased tobacco use. Among those with probable depression, 34% indicated increased alcohol use and 55.6% increased tobacco use. Workers with greater exposure were more likely to have probable PTSD and probable depression (ORs = 3.3 and 3.06, respectively). After adjusting for demographics and work demand, those with high exposure were more likely to have probable PTSD and probable depression (ORs = 3.21 and 3.13). Those with high exposure had increased alcohol and tobacco use (ORs = 3.01 and 3.40), and those with high work demand indicated increased alcohol and tobacco use (ORs = 1.98 and 2.10). High exposure and work demand predicted increased alcohol and tobacco use, after adjusting for demographics, work demand, and exposure. Work-related disaster mental and behavioral health burden indicate the need for additional mental health interventions in the public health disaster workforce.

Posttraumatic Stress Disorder, Depression, and Alcohol and Tobacco Use in Public Health Workers After the 2004 Florida Hurricanes

PubMed Central

Fullerton, Carol S.; McKibben, Jodi B.A.; Reissman, Dori B.; Scharf, Ted; Kowalski-Trakofler, Kathleen M.; Shultz, James M.; Ursano, Robert J.

2015-01-01

Objective We examined the relationship of probable posttraumatic stress disorder (PTSD), probable depression, and increased alcohol and/or tobacco use to disaster exposure and work demand in Florida Department of Health workers after the 2004 hurricanes. Methods Participants (N = 2249) completed electronic questionnaires assessing PTSD, depression, alcohol and tobacco use, hurricane exposure, and work demand. Results Total mental and behavioral health burden (probable PTSD, probable depression, increased alcohol and/or tobacco use) was 11%. More than 4% had probable PTSD, and 3.8% had probable depression. Among those with probable PTSD, 29.2% had increased alcohol use, and 50% had increased tobacco use. Among those with probable depression, 34% indicated increased alcohol use and 55.6% increased tobacco use. Workers with greater exposure were more likely to have probable PTSD and probable depression (ORs = 3.3 and 3.06, respectively). After adjusting for demographics and work demand, those with high exposure were more likely to have probable PTSD and probable depression (ORs = 3.21 and 3.13). Those with high exposure had increased alcohol and tobacco use (ORs = 3.01 and 3.40), and those with high work demand indicated increased alcohol and tobacco use (ORs = 1.98 and 2.10). High exposure and work demand predicted increased alcohol and tobacco use, after adjusting for demographics, work demand, and exposure. Conclusions Work-related disaster mental and behavioral health burden indicate the need for additional mental health interventions in the public health disaster workforce. PMID:24618140

Striatal activity is modulated by target probability.

PubMed

Hon, Nicholas

2017-06-14

Target probability has well-known neural effects. In the brain, target probability is known to affect frontal activity, with lower probability targets producing more prefrontal activation than those that occur with higher probability. Although the effect of target probability on cortical activity is well specified, its effect on subcortical structures such as the striatum is less well understood. Here, I examined this issue and found that the striatum was highly responsive to target probability. This is consistent with its hypothesized role in the gating of salient information into higher-order task representations. The current data are interpreted in light of that fact that different components of the striatum are sensitive to different types of task-relevant information.

Probability and Quantum Paradigms: the Interplay

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

Kracklauer, A. F.

Since the introduction of Born's interpretation of quantum wave functions as yielding the probability density of presence, Quantum Theory and Probability have lived in a troubled symbiosis. Problems arise with this interpretation because quantum probabilities exhibit features alien to usual probabilities, namely non Boolean structure and non positive-definite phase space probability densities. This has inspired research into both elaborate formulations of Probability Theory and alternate interpretations for wave functions. Herein the latter tactic is taken and a suggested variant interpretation of wave functions based on photo detection physics proposed, and some empirical consequences are considered. Although incomplete in a fewmore » details, this variant is appealing in its reliance on well tested concepts and technology.« less

A probability space for quantum models

NASA Astrophysics Data System (ADS)

Lemmens, L. F.

2017-06-01

A probability space contains a set of outcomes, a collection of events formed by subsets of the set of outcomes and probabilities defined for all events. A reformulation in terms of propositions allows to use the maximum entropy method to assign the probabilities taking some constraints into account. The construction of a probability space for quantum models is determined by the choice of propositions, choosing the constraints and making the probability assignment by the maximum entropy method. This approach shows, how typical quantum distributions such as Maxwell-Boltzmann, Fermi-Dirac and Bose-Einstein are partly related with well-known classical distributions. The relation between the conditional probability density, given some averages as constraints and the appropriate ensemble is elucidated.

The internal consistency of the standard gamble: tests after adjusting for prospect theory.

PubMed

Oliver, Adam

2003-07-01

This article reports a study that tests whether the internal consistency of the standard gamble can be improved upon by incorporating loss weighting and probability transformation parameters in the standard gamble valuation procedure. Five alternatives to the standard EU formulation are considered: (1) probability transformation within an EU framework; and, within a prospect theory framework, (2) loss weighting and full probability transformation, (3) no loss weighting and full probability transformation, (4) loss weighting and no probability transformation, and (5) loss weighting and partial probability transformation. Of the five alternatives, only the prospect theory formulation with loss weighting and no probability transformation offers an improvement in internal consistency over the standard EU valuation procedure.

Probability and Quantum Paradigms: the Interplay

NASA Astrophysics Data System (ADS)

Kracklauer, A. F.

2007-12-01

Since the introduction of Born's interpretation of quantum wave functions as yielding the probability density of presence, Quantum Theory and Probability have lived in a troubled symbiosis. Problems arise with this interpretation because quantum probabilities exhibit features alien to usual probabilities, namely non Boolean structure and non positive-definite phase space probability densities. This has inspired research into both elaborate formulations of Probability Theory and alternate interpretations for wave functions. Herein the latter tactic is taken and a suggested variant interpretation of wave functions based on photo detection physics proposed, and some empirical consequences are considered. Although incomplete in a few details, this variant is appealing in its reliance on well tested concepts and technology.

[Comparison of two algorithms for development of design space-overlapping method and probability-based method].

PubMed

Shao, Jing-Yuan; Qu, Hai-Bin; Gong, Xing-Chu

2018-05-01

In this work, two algorithms (overlapping method and the probability-based method) for design space calculation were compared by using the data collected from extraction process of Codonopsis Radix as an example. In the probability-based method, experimental error was simulated to calculate the probability of reaching the standard. The effects of several parameters on the calculated design space were studied, including simulation number, step length, and the acceptable probability threshold. For the extraction process of Codonopsis Radix, 10 000 times of simulation and 0.02 for the calculation step length can lead to a satisfactory design space. In general, the overlapping method is easy to understand, and can be realized by several kinds of commercial software without coding programs, but the reliability of the process evaluation indexes when operating in the design space is not indicated. Probability-based method is complex in calculation, but can provide the reliability to ensure that the process indexes can reach the standard within the acceptable probability threshold. In addition, there is no probability mutation in the edge of design space by probability-based method. Therefore, probability-based method is recommended for design space calculation. Copyright© by the Chinese Pharmaceutical Association.

Comparison of clinical probability-adjusted D-dimer and age-adjusted D-dimer interpretation to exclude venous thromboembolism.

PubMed

Takach Lapner, Sarah; Julian, Jim A; Linkins, Lori-Ann; Bates, Shannon; Kearon, Clive

2017-10-05

Two new strategies for interpreting D-dimer results have been proposed: i) using a progressively higher D-dimer threshold with increasing age (age-adjusted strategy) and ii) using a D-dimer threshold in patients with low clinical probability that is twice the threshold used in patients with moderate clinical probability (clinical probability-adjusted strategy). Our objective was to compare the diagnostic accuracy of age-adjusted and clinical probability-adjusted D-dimer interpretation in patients with a low or moderate clinical probability of venous thromboembolism (VTE). We performed a retrospective analysis of clinical data and blood samples from two prospective studies. We compared the negative predictive value (NPV) for VTE, and the proportion of patients with a negative D-dimer result, using two D-dimer interpretation strategies: the age-adjusted strategy, which uses a progressively higher D-dimer threshold with increasing age over 50 years (age in years × 10 µg/L FEU); and the clinical probability-adjusted strategy which uses a D-dimer threshold of 1000 µg/L FEU in patients with low clinical probability and 500 µg/L FEU in patients with moderate clinical probability. A total of 1649 outpatients with low or moderate clinical probability for a first suspected deep vein thrombosis or pulmonary embolism were included. The NPV of both the clinical probability-adjusted strategy (99.7 %) and the age-adjusted strategy (99.6 %) were similar. However, the proportion of patients with a negative result was greater with the clinical probability-adjusted strategy (56.1 % vs, 50.9 %; difference 5.2 %; 95 % CI 3.5 % to 6.8 %). These findings suggest that clinical probability-adjusted D-dimer interpretation is a better way of interpreting D-dimer results compared to age-adjusted interpretation.

A pilot study of naturally occurring high-probability request sequences in hostage negotiations.

PubMed

Hughes, James

2009-01-01

In the current study, the audiotapes from three hostage-taking situations were analyzed. Hostage negotiator requests to the hostage taker were characterized as either high or low probability. The results suggested that hostage-taker compliance to a hostage negotiator's low-probability request was more likely when a series of complied-with high-probability requests preceded the low-probability request. However, two of the three hostage-taking situations ended violently; therefore, the implications of the high-probability request sequence for hostage-taking situations should be assessed in future research.

A PILOT STUDY OF NATURALLY OCCURRING HIGH-PROBABILITY REQUEST SEQUENCES IN HOSTAGE NEGOTIATIONS

PubMed Central

Hughes, James

2009-01-01

In the current study, the audiotapes from three hostage-taking situations were analyzed. Hostage negotiator requests to the hostage taker were characterized as either high or low probability. The results suggested that hostage-taker compliance to a hostage negotiator's low-probability request was more likely when a series of complied-with high-probability requests preceded the low-probability request. However, two of the three hostage-taking situations ended violently; therefore, the implications of the high-probability request sequence for hostage-taking situations should be assessed in future research. PMID:19949541

Combined statistical analysis of landslide release and propagation

NASA Astrophysics Data System (ADS)

Mergili, Martin; Rohmaneo, Mohammad; Chu, Hone-Jay

2016-04-01

Statistical methods - often coupled with stochastic concepts - are commonly employed to relate areas affected by landslides with environmental layers, and to estimate spatial landslide probabilities by applying these relationships. However, such methods only concern the release of landslides, disregarding their motion. Conceptual models for mass flow routing are used for estimating landslide travel distances and possible impact areas. Automated approaches combining release and impact probabilities are rare. The present work attempts to fill this gap by a fully automated procedure combining statistical and stochastic elements, building on the open source GRASS GIS software: (1) The landslide inventory is subset into release and deposition zones. (2) We employ a traditional statistical approach to estimate the spatial release probability of landslides. (3) We back-calculate the probability distribution of the angle of reach of the observed landslides, employing the software tool r.randomwalk. One set of random walks is routed downslope from each pixel defined as release area. Each random walk stops when leaving the observed impact area of the landslide. (4) The cumulative probability function (cdf) derived in (3) is used as input to route a set of random walks downslope from each pixel in the study area through the DEM, assigning the probability gained from the cdf to each pixel along the path (impact probability). The impact probability of a pixel is defined as the average impact probability of all sets of random walks impacting a pixel. Further, the average release probabilities of the release pixels of all sets of random walks impacting a given pixel are stored along with the area of the possible release zone. (5) We compute the zonal release probability by increasing the release probability according to the size of the release zone - the larger the zone, the larger the probability that a landslide will originate from at least one pixel within this zone. We quantify this relationship by a set of empirical curves. (6) Finally, we multiply the zonal release probability with the impact probability in order to estimate the combined impact probability for each pixel. We demonstrate the model with a 167 km² study area in Taiwan, using an inventory of landslides triggered by the typhoon Morakot. Analyzing the model results leads us to a set of key conclusions: (i) The average composite impact probability over the entire study area corresponds well to the density of observed landside pixels. Therefore we conclude that the method is valid in general, even though the concept of the zonal release probability bears some conceptual issues that have to be kept in mind. (ii) The parameters used as predictors cannot fully explain the observed distribution of landslides. The size of the release zone influences the composite impact probability to a larger degree than the pixel-based release probability. (iii) The prediction rate increases considerably when excluding the largest, deep-seated, landslides from the analysis. We conclude that such landslides are mainly related to geological features hardly reflected in the predictor layers used.

Propensity, Probability, and Quantum Theory

NASA Astrophysics Data System (ADS)

Ballentine, Leslie E.

2016-08-01

Quantum mechanics and probability theory share one peculiarity. Both have well established mathematical formalisms, yet both are subject to controversy about the meaning and interpretation of their basic concepts. Since probability plays a fundamental role in QM, the conceptual problems of one theory can affect the other. We first classify the interpretations of probability into three major classes: (a) inferential probability, (b) ensemble probability, and (c) propensity. Class (a) is the basis of inductive logic; (b) deals with the frequencies of events in repeatable experiments; (c) describes a form of causality that is weaker than determinism. An important, but neglected, paper by P. Humphreys demonstrated that propensity must differ mathematically, as well as conceptually, from probability, but he did not develop a theory of propensity. Such a theory is developed in this paper. Propensity theory shares many, but not all, of the axioms of probability theory. As a consequence, propensity supports the Law of Large Numbers from probability theory, but does not support Bayes theorem. Although there are particular problems within QM to which any of the classes of probability may be applied, it is argued that the intrinsic quantum probabilities (calculated from a state vector or density matrix) are most naturally interpreted as quantum propensities. This does not alter the familiar statistical interpretation of QM. But the interpretation of quantum states as representing knowledge is untenable. Examples show that a density matrix fails to represent knowledge.

Trial type probability modulates the cost of antisaccades

PubMed Central

Chiau, Hui-Yan; Tseng, Philip; Su, Jia-Han; Tzeng, Ovid J. L.; Hung, Daisy L.; Muggleton, Neil G.

2011-01-01

The antisaccade task, where eye movements are made away from a target, has been used to investigate the flexibility of cognitive control of behavior. Antisaccades usually have longer saccade latencies than prosaccades, the so-called antisaccade cost. Recent studies have shown that this antisaccade cost can be modulated by event probability. This may mean that the antisaccade cost can be reduced, or even reversed, if the probability of surrounding events favors the execution of antisaccades. The probabilities of prosaccades and antisaccades were systematically manipulated by changing the proportion of a certain type of trial in an interleaved pro/antisaccades task. We aimed to disentangle the intertwined relationship between trial type probabilities and the antisaccade cost with the ultimate goal of elucidating how probabilities of trial types modulate human flexible behaviors, as well as the characteristics of such modulation effects. To this end, we examined whether implicit trial type probability can influence saccade latencies and also manipulated the difficulty of cue discriminability to see how effects of trial type probability would change when the demand on visual perceptual analysis was high or low. A mixed-effects model was applied to the analysis to dissect the factors contributing to the modulation effects of trial type probabilities. Our results suggest that the trial type probability is one robust determinant of antisaccade cost. These findings highlight the importance of implicit probability in the flexibility of cognitive control of behavior. PMID:21543748

Ubiquitous Log Odds: A Common Representation of Probability and Frequency Distortion in Perception, Action, and Cognition

PubMed Central

Zhang, Hang; Maloney, Laurence T.

2012-01-01

In decision from experience, the source of probability information affects how probability is distorted in the decision task. Understanding how and why probability is distorted is a key issue in understanding the peculiar character of experience-based decision. We consider how probability information is used not just in decision-making but also in a wide variety of cognitive, perceptual, and motor tasks. Very similar patterns of distortion of probability/frequency information have been found in visual frequency estimation, frequency estimation based on memory, signal detection theory, and in the use of probability information in decision-making under risk and uncertainty. We show that distortion of probability in all cases is well captured as linear transformations of the log odds of frequency and/or probability, a model with a slope parameter, and an intercept parameter. We then consider how task and experience influence these two parameters and the resulting distortion of probability. We review how the probability distortions change in systematic ways with task and report three experiments on frequency distortion where the distortions change systematically in the same task. We found that the slope of frequency distortions decreases with the sample size, which is echoed by findings in decision from experience. We review previous models of the representation of uncertainty and find that none can account for the empirical findings. PMID:22294978

PubMed

Rodríguez, Yarimar Rosa; Díaz, Nelson Varas

2008-01-01

El proceso de estigmatización asume una devaluación de la persona debido a una característica o marca que haya sido identificada socialmente y que permita que se le describa como diferente. Desde que se desató la epidemia del VIH/SIDA, vivir con la enfermedad ha sido señalado de manera social como una marca estigmatizante. Las manifestaciones de dicha estigmatización se han documentado entre profesionales de la salud. Este estigma puede afectar los servicios de salud que las personas que viven con VIH/SIDA reciben de estos profesionales. Los objetivos de esta investigación fueron explorar: 1) la percepción que tienen estudiantes y profesionales de la salud sobre su nivel de competencia para ofrecer servicios a personas que viven con VIH/SIDA, 2) las opiniones de éstos sobre el tipo de adiestramiento profesional recibido y la necesidad del mismo, y 3) la manifestación de actitudes estigmatizantes como indicadores de necesidad de adiestramiento profesional. La muestra total del estudio estuvo compuesta por 80 de diversas profesiones de la salud. Los resultados reflejan que algunos/as de los/as participantes han recibido formación en VIH pero ésta no ha sido suficiente para contrarrestar las nociones estigmatizantes. Discutimos las implicaciones de los resultados para investigaciones futuras y el desarrollo de intervenciones con vías de minimizar las nociones estigmatizantes en los escenarios de salud.

Estudio teórico de moléculas de interés en Astrofísica: compuestos binarios policarbonados

NASA Astrophysics Data System (ADS)

Largo-Cabrerizo, A.

Se han detectado en el espacio distintos compuestos binarios policarbonados (que se pueden formular como CnX), algunos de ellos con elementos de la primera fila del sistema periódico, pero también existen otros que contienen elementos de la segunda fila, como azufre o silicio. La información experimental sobre estos últimos compuestos es escasa, por lo que los estudios teóricos son especialmente valiosos en este campo. En esta comunicación presentaremos los avances mas recientes que sobre el tema ha realizado nuestro grupo. Incidiremos particularmente en dos aspectos. En primer lugar resumiremos los estudios en los que hemos intentado proporcionar información estructural sobre carburos metálicos formados por sodio, magnesio, aluminio o calcio, que pueda ser de ayuda a la hora de caracterizar estas moléculas en laboratorio como paso previo a su eventual detección en el espacio. Un aspecto importante dentro de este primer apartado es el análisis de las propiedades moleculares en función del tamaño del sistema (cuantificado en el numero de átomos de carbono) con el objeto de intentar sistematizar su estudio. En segundo lugar comentaremos brevemente algunos de los estudios realizados sobre posibles reacciones que pueden ser vías de síntesis de este tipo de compuestos en el medio interestelar.

Resposta do detector de ondas gravitacionais Mario Schenberg ao "ringdown" de buraco negros

NASA Astrophysics Data System (ADS)

Costa, C. A.; Aguiar, O. D.; Magalhães, N. S.

2003-08-01

Acredita-se que quando duas estrelas de nêutrons coalescem, elas, eventualmente, formam um buraco negro com massa igual a soma das massas dos objetos originais. Durante a formação do buraco negro, o espaço-tempo em torno do sistema sofre perturbações que se propagam na forma de radiação gravitacional. A forma de onda associada a radiação gravitacional, durante este estágio, aproxima-se a uma senóide exponencialmente amortecida. Este tipo de sinal é conhecido como "ringdown", e seu comportamento e parametrização são muito bem conhecidos. Neste trabalho, simulamos computacionalmente sinais provenientes do "ringdown" de buracos negros, com a finalidade de testar o desempenho do detector de ondas gravitacionais Mario Schenberg em observá-los, quando entrar em funcionamento. Este primeiro teste teórico ajudou-nos a criar estratégias de detecção de sinais imersos no ruído instrumental. Calculamos a relação sinal-ruído como uma função da frequência, bem como sua integral dentro da faixa de sensibilidade do detector. Os resultados obtidos mostraram que o detector Schenberg terá sensibilidade suficiente para detectar este tipo de sinal, proveniente de fontes astrofísicas localizadas dentro de um raio de ~100kpc.

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

PubMed Central

Lana, Francisco C. F.; Malvárez, Silvina

2012-01-01

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

Perda de massa em ventos empoeirados de estrelas supergigantes

NASA Astrophysics Data System (ADS)

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

2003-08-01

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

Probability workshop to be better in probability topic

NASA Astrophysics Data System (ADS)

Asmat, Aszila; Ujang, Suriyati; Wahid, Sharifah Norhuda Syed

2015-02-01

The purpose of the present study was to examine whether statistics anxiety and attitudes towards probability topic among students in higher education level have an effect on their performance. 62 fourth semester science students were given statistics anxiety questionnaires about their perception towards probability topic. Result indicated that students' performance in probability topic is not related to anxiety level, which means that the higher level in statistics anxiety will not cause lower score in probability topic performance. The study also revealed that motivated students gained from probability workshop ensure that their performance in probability topic shows a positive improvement compared before the workshop. In addition there exists a significance difference in students' performance between genders with better achievement among female students compared to male students. Thus, more initiatives in learning programs with different teaching approaches is needed to provide useful information in improving student learning outcome in higher learning institution.

Probability shapes perceptual precision: A study in orientation estimation.

PubMed

Jabar, Syaheed B; Anderson, Britt

2015-12-01

Probability is known to affect perceptual estimations, but an understanding of mechanisms is lacking. Moving beyond binary classification tasks, we had naive participants report the orientation of briefly viewed gratings where we systematically manipulated contingent probability. Participants rapidly developed faster and more precise estimations for high-probability tilts. The shapes of their error distributions, as indexed by a kurtosis measure, also showed a distortion from Gaussian. This kurtosis metric was robust, capturing probability effects that were graded, contextual, and varying as a function of stimulus orientation. Our data can be understood as a probability-induced reduction in the variability or "shape" of estimation errors, as would be expected if probability affects the perceptual representations. As probability manipulations are an implicit component of many endogenous cuing paradigms, changes at the perceptual level could account for changes in performance that might have traditionally been ascribed to "attention." (c) 2015 APA, all rights reserved).

Dangerous "spin": the probability myth of evidence-based prescribing - a Merleau-Pontyian approach.

PubMed

Morstyn, Ron

2011-08-01

The aim of this study was to examine logical positivist statistical probability statements used to support and justify "evidence-based" prescribing rules in psychiatry when viewed from the major philosophical theories of probability, and to propose "phenomenological probability" based on Maurice Merleau-Ponty's philosophy of "phenomenological positivism" as a better clinical and ethical basis for psychiatric prescribing. The logical positivist statistical probability statements which are currently used to support "evidence-based" prescribing rules in psychiatry have little clinical or ethical justification when subjected to critical analysis from any of the major theories of probability and represent dangerous "spin" because they necessarily exclude the individual , intersubjective and ambiguous meaning of mental illness. A concept of "phenomenological probability" founded on Merleau-Ponty's philosophy of "phenomenological positivism" overcomes the clinically destructive "objectivist" and "subjectivist" consequences of logical positivist statistical probability and allows psychopharmacological treatments to be appropriately integrated into psychiatric treatment.

Importance Sampling in the Evaluation and Optimization of Buffered Failure Probability

DTIC Science & Technology

2015-07-01

12th International Conference on Applications of Statistics and Probability in Civil Engineering, ICASP12 Vancouver, Canada, July 12-15, 2015...Importance Sampling in the Evaluation and Optimization of Buffered Failure Probability Marwan M. Harajli Graduate Student, Dept. of Civil and Environ...criterion is usually the failure probability . In this paper, we examine the buffered failure probability as an attractive alternative to the failure

Estudio del comportamiento tribologico y de las interacciones de superficie de nuevos nanofluidos ionicos

NASA Astrophysics Data System (ADS)

Espinosa Rodriguez, Tulia

Ionic liquids are molten salts which are liquid at room temperature or at low temperatures and present a unique combination of properties. In the present work, we focus on their use as lubricants in complex tribological problems such as the lubrication of metals that slide against themselves, the development of water based lubricants and new self-lubricated surfaces. When it is difficult to reduce friction and wear by lubrication, as in the case of magnesium alloys, ionic liquids are studied as protective coatings precursors. Surface interactions and corrosion processes with protic and aprotic ionic liquids on copper and steel have been determined in order to develop new lubricants and lubricant additives. In the copper/copper contact, all ionic liquids present better tribological performance than the polyalphaolefin synthetic oil, except for the oleate derivative. New protic ionic liquids are not only exceptional lubricants of the steel/sapphire contact as neat lubricants, but when they are used as additives in water, the formation of a boundary layer after water evaporation occurs, thus reducing friction and wear. The formation of this boundary layer on steel under static conditions is described in order to prevent the running-in period with respect to the solution of ionic liquid in water. The best lubricating behaviour for the copper/copper contact and also for the steel/sapphire contact is obtained for the diprotic ammonium dianionic adipate, that has two carboxylate groups in its anion. A higher polarity and a higher number of ammonium protons, carboxylate and hydroxyl groups would give rise to stronger surface interaction with the metal surfaces and more stable boundary films. The tribological performance of new aprotic thiazolium ionic liquids and commercial aprotic imidazolium ionic liquids has been compared as lubricants of the steel/sapphire contact, obtaining the best results for the bis(trifluoromethanesulfonyl)imide derivatives, and also preventing tribocorrosion processes. The formation of a coating layer on magnesium alloys from phosphonate imidazolium ionic liquids by immersion and by chronoamperometry has been described. The new coatings reduce the abrasive wear in the magnesium-aluminium alloy but they are not effective in the magnesium-zinc alloy, which prevent the formation of continuous coatings. Los liquidos ionicos son sales liquidas a temperatura ambiente o bajas temperaturas que presentan excelentes propiedades fisico-quimicas. En el presente trabajo se estudian como lubricantes en problemas tribologicos complejos como la lubricacion de metales contra si mismos, el desarrollo de lubricantes base agua y de nuevas superficies autolubricadas. Cuando no es posible reducir la friccion y desgaste mediante lubricacion, como en las aleaciones de magnesio, los liquidos ionicos se han estudiado como precursores de recubrimientos protectores. Se han determinado las interacciones superficiales y los procesos de corrosion sobre cobre y sobre acero con diferentes liquidos ionicos proticos y aproticos para desarrollar nuevos lubricantes y aditivos. En el contacto cobre/cobre, excepto el liquido ionico protico derivado del oleato, todos los liquidos ionicos estudiados presentan mejor comportamiento tribologico que el lubricante comercial Polialfaolefina 6. En el contacto acero/zafiro, los nuevos liquidos ionicos proticos son buenos lubricantes cuando se utilizan en estado puro, y, como aditivos en agua, generan peliculas adsorbidas sobre la superficie del metal reduciendo la friccion y el desgaste tras la evaporacion del agua. Para evitar el periodo de alta friccion inicial en presencia de agua, se han generado peliculas superficiales de liquido ionico sobre el acero en condiciones estaticas. El mejor comportamiento lubricante tanto en el contacto cobre/cobre como en el contacto acero/zafiro se obtiene para el liquido ionico protico derivado del anion adipato, con dos grupos carboxilicos. Las interacciones de los grupos hidroxilo y carboxilato con la superficie metalica y los puentes de hidrogeno entre cation y anion podrian ser los responsables del buen comportamiento tribologico. Se ha comparado el comportamiento tribologico de los liquidos ionicos aproticos derivados de imidazolio y tiazolio como lubricantes del contacto acero/zafiro, obteniendose los mejores resultados para los derivados del anion bis(trifluorometanosulfonil)imida, que evita a su vez los procesos de tribocorrosion. Se han generado recubrimientos sobre aleaciones de magnesio con tres liquidos ionicos derivados del anion fosfonato, tanto por inmersion como mediante cronoamperometria. Los nuevos recubrimientos reducen el dano superficial por deslizamiento o abrasion de la aleacion magnesio-aluminio pero no de la aleacion magnesio-cinc, que impide la formacion de recubrimientos continuos.

The clinical diagnostic reasoning process determining the use of endoscopy in diagnosing peptic ulcer disease.

PubMed

Gul, Naheed; Quadri, Mujtaba

2011-09-01

To evaluate the clinical diagnostic reasoning process as a tool to decrease the number of unnecessary endoscopies for diagnosing peptic ulcer disease. tudy Cross-sectional KAP study. Shifa College of Medicine, Islamabad, from April to August 2010. Two hundred doctors were assessed with three common clinical scenarios of low, intermediate and high pre-test probability for peptic ulcer disease using a questionnaire. The differences between the reference estimates and the respondents' estimates of pre-test and post test probability were used for assessing the ability of estimating the pretest probability and the post test probability of the disease. Doctors were also enquired about the cost-effectiveness and safety of endoscopy. Consecutive sampling technique was used and the data was analyzed using SPSS version 16. In the low pre-test probability settings, overestimation of the disease probability suggested the doctors' inability to rule out the disease. The post test probabilities were similarly overestimated. In intermediate pre-test probability settings, both over and under estimation of probabilities were noticed. In high pre-test probability setting, there was no significant difference in the reference and the responders' intuitive estimates of post test probability. Doctors were more likely to consider ordering the test as the disease probability increased. Most respondents were of the opinion that endoscopy is not a cost-effective procedure and may be associated with a potential harm. Improvement is needed in doctors' diagnostic ability by more emphasis on clinical decision-making and application of bayesian probabilistic thinking to real clinical situations.

The relationship between species detection probability and local extinction probability

USGS Publications Warehouse

Alpizar-Jara, R.; Nichols, J.D.; Hines, J.E.; Sauer, J.R.; Pollock, K.H.; Rosenberry, C.S.

2004-01-01

In community-level ecological studies, generally not all species present in sampled areas are detected. Many authors have proposed the use of estimation methods that allow detection probabilities that are < 1 and that are heterogeneous among species. These methods can also be used to estimate community-dynamic parameters such as species local extinction probability and turnover rates (Nichols et al. Ecol Appl 8:1213-1225; Conserv Biol 12:1390-1398). Here, we present an ad hoc approach to estimating community-level vital rates in the presence of joint heterogeneity of detection probabilities and vital rates. The method consists of partitioning the number of species into two groups using the detection frequencies and then estimating vital rates (e.g., local extinction probabilities) for each group. Estimators from each group are combined in a weighted estimator of vital rates that accounts for the effect of heterogeneity. Using data from the North American Breeding Bird Survey, we computed such estimates and tested the hypothesis that detection probabilities and local extinction probabilities were negatively related. Our analyses support the hypothesis that species detection probability covaries negatively with local probability of extinction and turnover rates. A simulation study was conducted to assess the performance of vital parameter estimators as well as other estimators relevant to questions about heterogeneity, such as coefficient of variation of detection probabilities and proportion of species in each group. Both the weighted estimator suggested in this paper and the original unweighted estimator for local extinction probability performed fairly well and provided no basis for preferring one to the other.

Dynamic analysis of pedestrian crossing behaviors on traffic flow at unsignalized mid-block crosswalks

NASA Astrophysics Data System (ADS)

Liu, Gang; He, Jing; Luo, Zhiyong; Yang, Wunian; Zhang, Xiping

2015-05-01

It is important to study the effects of pedestrian crossing behaviors on traffic flow for solving the urban traffic jam problem. Based on the Nagel-Schreckenberg (NaSch) traffic cellular automata (TCA) model, a new one-dimensional TCA model is proposed considering the uncertainty conflict behaviors between pedestrians and vehicles at unsignalized mid-block crosswalks and defining the parallel updating rules of motion states of pedestrians and vehicles. The traffic flow is simulated for different vehicle densities and behavior trigger probabilities. The fundamental diagrams show that no matter what the values of vehicle braking probability, pedestrian acceleration crossing probability, pedestrian backing probability and pedestrian generation probability, the system flow shows the "increasing-saturating-decreasing" trend with the increase of vehicle density; when the vehicle braking probability is lower, it is easy to cause an emergency brake of vehicle and result in great fluctuation of saturated flow; the saturated flow decreases slightly with the increase of the pedestrian acceleration crossing probability; when the pedestrian backing probability lies between 0.4 and 0.6, the saturated flow is unstable, which shows the hesitant behavior of pedestrians when making the decision of backing; the maximum flow is sensitive to the pedestrian generation probability and rapidly decreases with increasing the pedestrian generation probability, the maximum flow is approximately equal to zero when the probability is more than 0.5. The simulations prove that the influence of frequent crossing behavior upon vehicle flow is immense; the vehicle flow decreases and gets into serious congestion state rapidly with the increase of the pedestrian generation probability.

Defining Probability in Sex Offender Risk Assessment.

PubMed

Elwood, Richard W

2016-12-01

There is ongoing debate and confusion over using actuarial scales to predict individuals' risk of sexual recidivism. Much of the debate comes from not distinguishing Frequentist from Bayesian definitions of probability. Much of the confusion comes from applying Frequentist probability to individuals' risk. By definition, only Bayesian probability can be applied to the single case. The Bayesian concept of probability resolves most of the confusion and much of the debate in sex offender risk assessment. Although Bayesian probability is well accepted in risk assessment generally, it has not been widely used to assess the risk of sex offenders. I review the two concepts of probability and show how the Bayesian view alone provides a coherent scheme to conceptualize individuals' risk of sexual recidivism.

UT Biomedical Informatics Lab (BMIL) probability wheel

NASA Astrophysics Data System (ADS)

Huang, Sheng-Cheng; Lee, Sara; Wang, Allen; Cantor, Scott B.; Sun, Clement; Fan, Kaili; Reece, Gregory P.; Kim, Min Soon; Markey, Mia K.

A probability wheel app is intended to facilitate communication between two people, an "investigator" and a "participant", about uncertainties inherent in decision-making. Traditionally, a probability wheel is a mechanical prop with two colored slices. A user adjusts the sizes of the slices to indicate the relative value of the probabilities assigned to them. A probability wheel can improve the adjustment process and attenuate the effect of anchoring bias when it is used to estimate or communicate probabilities of outcomes. The goal of this work was to develop a mobile application of the probability wheel that is portable, easily available, and more versatile. We provide a motivating example from medical decision-making, but the tool is widely applicable for researchers in the decision sciences.

PROBABILITY SURVEYS , CONDITIONAL PROBABILITIES AND ECOLOGICAL RISK ASSESSMENT

EPA Science Inventory

We show that probability-based environmental resource monitoring programs, such as the U.S. Environmental Protection Agency's (U.S. EPA) Environmental Monitoring and Assessment Program, and conditional probability analysis can serve as a basis for estimating ecological risk over ...

CPROB: A COMPUTATIONAL TOOL FOR CONDUCTING CONDITIONAL PROBABILITY ANALYSIS

EPA Science Inventory

Conditional probability analysis measures the probability of observing one event given that another event has occurred. In an environmental context, conditional probability analysis helps assess the association between an environmental contaminant (i.e. the stressor) and the ec...

PROBABILITY SURVEYS, CONDITIONAL PROBABILITIES, AND ECOLOGICAL RISK ASSESSMENT

EPA Science Inventory

We show that probability-based environmental resource monitoring programs, such as U.S. Environmental Protection Agency's (U.S. EPA) Environmental Monitoring and Asscssment Program EMAP) can be analyzed with a conditional probability analysis (CPA) to conduct quantitative probabi...

Tuned by experience: How orientation probability modulates early perceptual processing.

PubMed

Jabar, Syaheed B; Filipowicz, Alex; Anderson, Britt

2017-09-01

Probable stimuli are more often and more quickly detected. While stimulus probability is known to affect decision-making, it can also be explained as a perceptual phenomenon. Using spatial gratings, we have previously shown that probable orientations are also more precisely estimated, even while participants remained naive to the manipulation. We conducted an electrophysiological study to investigate the effect that probability has on perception and visual-evoked potentials. In line with previous studies on oddballs and stimulus prevalence, low-probability orientations were associated with a greater late positive 'P300' component which might be related to either surprise or decision-making. However, the early 'C1' component, thought to reflect V1 processing, was dampened for high-probability orientations while later P1 and N1 components were unaffected. Exploratory analyses revealed a participant-level correlation between C1 and P300 amplitudes, suggesting a link between perceptual processing and decision-making. We discuss how these probability effects could be indicative of sharpening of neurons preferring the probable orientations, due either to perceptual learning, or to feature-based attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

Decision analysis with approximate probabilities

NASA Technical Reports Server (NTRS)

Whalen, Thomas

1992-01-01

This paper concerns decisions under uncertainty in which the probabilities of the states of nature are only approximately known. Decision problems involving three states of nature are studied. This is due to the fact that some key issues do not arise in two-state problems, while probability spaces with more than three states of nature are essentially impossible to graph. The primary focus is on two levels of probabilistic information. In one level, the three probabilities are separately rounded to the nearest tenth. This can lead to sets of rounded probabilities which add up to 0.9, 1.0, or 1.1. In the other level, probabilities are rounded to the nearest tenth in such a way that the rounded probabilities are forced to sum to 1.0. For comparison, six additional levels of probabilistic information, previously analyzed, were also included in the present analysis. A simulation experiment compared four criteria for decisionmaking using linearly constrained probabilities (Maximin, Midpoint, Standard Laplace, and Extended Laplace) under the eight different levels of information about probability. The Extended Laplace criterion, which uses a second order maximum entropy principle, performed best overall.

Influence of gravel mining and other factors on detection probabilities of Coastal Plain fishes in the Mobile River Basin, Alabama

USGS Publications Warehouse

Hayer, C.-A.; Irwin, E.R.

2008-01-01

We used an information-theoretic approach to examine the variation in detection probabilities for 87 Piedmont and Coastal Plain fishes in relation to instream gravel mining in four Alabama streams of the Mobile River drainage. Biotic and abiotic variables were also included in candidate models. Detection probabilities were heterogeneous across species and varied with habitat type, stream, season, and water quality. Instream gravel mining influenced the variation in detection probabilities for 38% of the species collected, probably because it led to habitat loss and increased sedimentation. Higher detection probabilities were apparent at unmined sites than at mined sites for 78% of the species for which gravel mining was shown to influence detection probabilities, indicating potential negative impacts to these species. Physical and chemical attributes also explained the variation in detection probabilities for many species. These results indicate that anthropogenic impacts can affect detection probabilities for fishes, and such variation should be considered when developing monitoring programs or routine sampling protocols. ?? Copyright by the American Fisheries Society 2008.

Probability cueing of distractor locations: both intertrial facilitation and statistical learning mediate interference reduction.

PubMed

Goschy, Harriet; Bakos, Sarolta; Müller, Hermann J; Zehetleitner, Michael

2014-01-01

Targets in a visual search task are detected faster if they appear in a probable target region as compared to a less probable target region, an effect which has been termed "probability cueing." The present study investigated whether probability cueing cannot only speed up target detection, but also minimize distraction by distractors in probable distractor regions as compared to distractors in less probable distractor regions. To this end, three visual search experiments with a salient, but task-irrelevant, distractor ("additional singleton") were conducted. Experiment 1 demonstrated that observers can utilize uneven spatial distractor distributions to selectively reduce interference by distractors in frequent distractor regions as compared to distractors in rare distractor regions. Experiments 2 and 3 showed that intertrial facilitation, i.e., distractor position repetitions, and statistical learning (independent of distractor position repetitions) both contribute to the probability cueing effect for distractor locations. Taken together, the present results demonstrate that probability cueing of distractor locations has the potential to serve as a strong attentional cue for the shielding of likely distractor locations.

Target intersection probabilities for parallel-line and continuous-grid types of search

USGS Publications Warehouse

McCammon, R.B.

1977-01-01

The expressions for calculating the probability of intersection of hidden targets of different sizes and shapes for parallel-line and continuous-grid types of search can be formulated by vsing the concept of conditional probability. When the prior probability of the orientation of a widden target is represented by a uniform distribution, the calculated posterior probabilities are identical with the results obtained by the classic methods of probability. For hidden targets of different sizes and shapes, the following generalizations about the probability of intersection can be made: (1) to a first approximation, the probability of intersection of a hidden target is proportional to the ratio of the greatest dimension of the target (viewed in plane projection) to the minimum line spacing of the search pattern; (2) the shape of the hidden target does not greatly affect the probability of the intersection when the largest dimension of the target is small relative to the minimum spacing of the search pattern, (3) the probability of intersecting a target twice for a particular type of search can be used as a lower bound if there is an element of uncertainty of detection for a particular type of tool; (4) the geometry of the search pattern becomes more critical when the largest dimension of the target equals or exceeds the minimum spacing of the search pattern; (5) for elongate targets, the probability of intersection is greater for parallel-line search than for an equivalent continuous square-grid search when the largest dimension of the target is less than the minimum spacing of the search pattern, whereas the opposite is true when the largest dimension exceeds the minimum spacing; (6) the probability of intersection for nonorthogonal continuous-grid search patterns is not greatly different from the probability of intersection for the equivalent orthogonal continuous-grid pattern when the orientation of the target is unknown. The probability of intersection for an elliptically shaped target can be approximated by treating the ellipse as intermediate between a circle and a line. A search conducted along a continuous rectangular grid can be represented as intermediate between a search along parallel lines and along a continuous square grid. On this basis, an upper and lower bound for the probability of intersection of an elliptically shaped target for a continuous rectangular grid can be calculated. Charts have been constructed that permit the values for these probabilities to be obtained graphically. The use of conditional probability allows the explorationist greater flexibility in considering alternate search strategies for locating hidden targets. ?? 1977 Plenum Publishing Corp.

Monóxido de carbono

EPA Pesticide Factsheets

La mayoria de los accidentes causados por envenenamiento por monoxido de carbono (CO) se producen en los hogares y estan relacionados a nuestras actividades diarias como cocinar y usar la calefaccion.

Probability Surveys, Conditional Probability, and Ecological Risk Assessment

EPA Science Inventory

We show that probability-based environmental resource monitoring programs, such as the U.S. Environmental Protection Agency’s (U.S. EPA) Environmental Monitoring and Assessment Program, and conditional probability analysis can serve as a basis for estimating ecological risk over ...

Using Playing Cards to Differentiate Probability Interpretations

ERIC Educational Resources Information Center

López Puga, Jorge

2014-01-01

The aprioristic (classical, naïve and symmetric) and frequentist interpretations of probability are commonly known. Bayesian or subjective interpretation of probability is receiving increasing attention. This paper describes an activity to help students differentiate between the three types of probability interpretations.

If Your Child Learns in Two Languages: A Parent's Guide for Improving Educational Opportunities for Children Acquiring English as a Second Language = Si su nino aprende en dos idiomes: Una guia para que las familias sepan como mejorar las oportunidades educativas de los ninos que adquieren el ingles como segunda lengua = Neu lon Ban Hoc Bang Hai Thu Tieng: Chi-nam cua phu-huynh de cai tien co hoi hoc van cua con em dang hoc Anh van nhu sinh ngu thu hai.

ERIC Educational Resources Information Center

Zelasko, Nancy; Antunez, Beth

This guide, in English, Spanish, and Vietnamese, aims to inform parents of students who have learned or are learning English as a Second Language about appropriate approaches for educating children so that they can work with schools to ensure a high quality education for their children. The emphasis is on explaining the laws, schools, and research…

Enhanced hydrogen evolution reaction on hybrids of cobalt phosphide and molybdenum phosphide

NASA Astrophysics Data System (ADS)

Fang, Si-Ling; Chou, Tsu-Chin; Samireddi, Satyanarayana; Chen, Kuei-Hsien; Chen, Li-Chyong; Chen, Wei-Fu

2017-03-01

Production of hydrogen from water electrolysis has stimulated the search of sustainable electrocatalysts as possible alternatives. Recently, cobalt phosphide (CoP) and molybdenum phosphide (MoP) received great attention owing to their superior catalytic activity and stability towards the hydrogen evolution reaction (HER) which rivals platinum catalysts. In this study, we synthesize and study a series of catalysts based on hybrids of CoP and MoP with different Co/Mo ratio. The HER activity shows a volcano shape and reaches a maximum for Co/Mo = 1. Tafel analysis indicates a change in the dominating step of Volmer-Hyrovský mechanism. Interestingly, X-ray diffraction patterns confirmed a major ternary interstitial hexagonal CoMoP2 crystal phase is formed which enhances the electrochemical activity.

Conceptos Basicos Sobre el Propano (in Spanish)

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

El propano provee energia a mas de 143.000 vehiculos en los Estados Unidos y 23 millones en todo el mundo. Flotas de todos los Estados Unidos han implementado con exito el uso de vehiculos que funcionan con gas propano, y en la actualidad varios funcionan gracias a este gas, incluyendo autobuses escolares, lanzaderas y autobuses publicos, asi como tambien furgonetas, taxis, vehiculos utilizados por las fuerzas del orden, barredoras de calles y camiones para uso profesional. El propano tambien se utiliza con frecuencia en aplicaciones fuera de la carretera, tales como montacargas, podadoras y equipos de uso profesional y otrosmore » equipos agricolas. Las ventajas del propano incluyen la disponibilidad interna, su rendimiento y el hecho de que genera menos emisiones de gases contaminantes que otras alternativas energeticas.« less

Spanish Summary (Nuevos meteoritos encountrados en lmilac)

NASA Astrophysics Data System (ADS)

1987-03-01

Desde tiempos prehistoricos han sido coleccionadas piedras que caen dei cielo. Hasta hace poco eran la unica fuente para hacer estudios de laboratorio de la materia extragal, ktica, e incluso en nuestra era espacial, siguen siendo una valiosa fuente de investigacion de la temprana historia dei sistema solar. Se estima que como termine medio cada kilometro cuadrado de la superficie terrestre es golpeada cada millon de aiios por un meteorito con un pese superior a 500 gramos. La mayoria se pierden en los oceanos 0 caen en regiones con escasa poblacion. Como resultado, los museos en el munda reciben anualmente tan solo alrededor de 6 meteoritos cuya caida fuera atestiguada. Otros llegan por hallazgos casuales que en la mayoria de los casos son meteoritos que han cardo en tiempos prehistoricos.

[Competence in biocentric ethics.

PubMed

Stepke, Fernando Lolas

2012-07-01

ResumenEste artículo explora el origen y la conceptualización de la bioética en tanto ética biocéntrica, definida por el pionero Fritz Jahr como un imperativo hipotético que llama a respetar la vida en todas sus formas. Tras describirla como proceso social, procedimiento técnico y producto académico, se enumeran y comentan algunas competencias que debieran presidir el empleo del discurso bioético en cualquier punto del complejo social "investigación médica": miembros de comités de ética de investigación, investigadores, empresarios, administradores. Cada uno de estos grupos, en su "cultura epistémica" propia, define y explicita los principios básicos en tanto expresión de valores y leyes generales.

Tal Como Somos/just as we are: an educational film to reduce stigma toward gay and bisexual men, transgender individuals, and persons living with HIV/AIDS.

PubMed

Ramirez-Valles, Jesus; Kuhns, Lisa M; Manjarrez, Dianna

2014-04-01

In this article, the authors describe the development and dissemination of a film-based educational intervention to reduce negative attitudes toward gay and bisexual men, transgender women, and people living with HIV/AIDS in Latino communities, with a focus on youth. The intervention, Tal Como Somos/Just as We Are, is based on stigma and attribution theories, extensive formative research, and community input. Evaluation findings among educators and school youth suggest the film has the potential to effectively influence attitudes toward gay and bisexual men, transgender women, and people living with HIV/AIDS. The film and intervention are being disseminated using diffusion of innovations theory through community-based organizations, schools, television broadcasting, and film festivals.

Investigación del USGS sobre el ecosistema de arrecifes de coral en el Atlántico

USGS Publications Warehouse

Kuffner, Ilsa B.; Yates, Kimberly K.; Zawada, David G.; Richey, Julie N.; Kellogg, Christina A.; Toth, Lauren T.; Torres-Garcia, Legna M.

2015-10-23

Los arrecifes de coral son estructuras sólidas, biomineralizadas que protegen comunidades costeras actuando como barreras protectoras de peligros tales como los huracanes y los tsunamis. Estos proveen arena a las playas a través de procesos naturales de erosión, fomentan la industria del turismo, las actividades recreacionales y proveen hábitats pesqueros esenciales. La conti-nua degradación mundial de ecosistemas de arrecifes de coral está bien documentada. Existe la necesidad de enfoque y organización de la ciencia para entender los procesos complejos físicos y biológicos e interacciones que están afectando el estado de los arrecifes coralinos y su capacidad para responder a un entorno cambiante.

Astronomy in the Classroom: Why? (Spanish Title: Astronomía en la Clase: ¿Por Qué?) Astronomia na Sala de Aula: Por Quê?

NASA Astrophysics Data System (ADS)

Daros Gama, Leandro; Bagdonas Henrique, Alexandre

2010-07-01

There are many discussions about the relevance of the topics covered in classes. One subject in particular is the focus of this essay: astronomy. In what sense and to what extent it would be worth to teach it in science or other kind of classes? In this paper we discuss some aspects of the advantages of dealing with this area of knowledge in schools, taking into account the epistemological and axiological dimensions of astronomy, in light of the vision of science as an intelligent dialogue with the world (Bachelard), in addition to the "problematization" knowledge of Paulo Freire. We propose that in fact the Astronomy does not need to be seen as just a new set of contents to be taught, but appears as a set of motivational contents for historical-philosophical discussions, and permit the discussion of concepts of other disciplines. Numerosas discusiones se están llevando a cabo acerca de la pertinencia de los temas tradicionalmente tratados en las clases. Uno de los temas, en particular, es el foco de este ensayo: la astronomía. ¿En qué sentido y en qué medida sería conveniente tratarla en clase, ya sea en clases de ciencias naturales, específicamente en las de astronomía o asignaturas afines? Elaboramos en este artículo algunos aspectos de las ventajas de tratar esta área del conocimiento en las escuelas, teniendo en cuenta las dimensiones epistemológica y axiológica de la astronomía, a la luz de la visión de la ciencia como un diálogo inteligente con el mundo (Bachelard), además de la propuesta del conocimiento "problematizador" de Paulo Freire. Proponemos que en realidad la astronomía no tiene por qué ser vista sólo como un nuevo conjunto de contenidos que se enseñan, sino que aparece como un conjunto de temas de motivación para el debate histórico-filosófico y para permitir la discusión de los conceptos típicos de otras disciplinas. Muitas discussões vêm acontecendo sobre a relevância dos temas abordados em sala de aula. Um tema, em particular, é foco deste ensaio: a astronomia. Em que sentido e em que medida valeria a pena abordá-la em aulas, seja de ciências, seja de astronomia especificamente, ou em disciplinas afins? Discutimos neste texto alguns aspectos das vantagens de se tratar essa área do conhecimento nas escolas, levando em conta as dimensões epistemológica e axiológica da astronomia, à luz da visão da ciência como um diálogo inteligente com o mundo, de Bachelard, além da proposta de problematização do conhecimento, de Paulo Freire. Proporemos que de fato a astronomia não precisa ser vista como apenas um novo conjunto de conteúdos a serem ensinados, mas figura como conjunto de temas motivadores para discussões histórico-filosóficas, além de permitir a abordagem de conceitos típicos de outras disciplinas.

Health and innovation: economic dynamics and Welfare State in Brazil.

PubMed

Gadelha, Carlos Augusto Grabois; Braga, Patrícia Seixas da Costa

2016-11-03

The effective enforcement of the access to healthcare as fundamental right requires an important theoretical and political effort at linking the often contradictory economic and social dimensions of development. This study suggests the need for a systemic view of policies related to the industrial base and innovation in health and the construction of the Brazilian Unified National Health System (SUS). The authors investigate the relations between health, innovation, and development, seeking to show and update the political, economic, and social determinants of the recent Brazilian experience with the Health Economic-Industrial Complex (HEIC). They discuss how the agenda for innovation and domestic industrial production in health gained a central place in the project for construction of the SUS. The article thus seeks to link inherent issues from the agenda for development, production, and innovation to social policy in healthcare, as observed in recent years, and based on this analysis, points to political and conceptual challenges for implementing the SUS, especially as regards strengthening its technological and industrial base. As a byproduct, the article develops an analytical and factual focus on the consolidation of the HEIC in Brazil, both as a dynamic vector of industrial development, generating investment, income, employment, and innovations, and as a decisive element for reducing vulnerability and structural dependence in health. The authors aim to show that strengthening the SUS and orienting it to social needs is an essential part of building a social Welfare State in Brazil. Resumo: A efetivação da saúde como um direito fundamental exige importante esforço, teórico e político, de articulação das dimensões econômicas e sociais, por vezes contraditórias, do desenvolvimento. Este trabalho indica a necessidade de um olhar sistêmico das políticas relacionadas à base produtiva e de inovação em saúde e à construção do Sistema Único de Saúde (SUS). Investiga as relações entre saúde, inovação e desenvolvimento, buscando mostrar e atualizar os determinantes políticos, econômicos e sociais da experiência brasileira recente relacionada ao Complexo Econômico-Industrial da Saúde (CEIS). Mostra como a agenda da inovação e da produção nacional em saúde ganhou centralidade no projeto de construção do SUS. O artigo procura, assim, articular questões inerentes à agenda do desenvolvimento, da produção e da inovação com a política social em saúde, tal como observado nos últimos anos e, valendo-se de sua análise, aponta desafios políticos e conceituais para a efetivação do SUS, em especial no que se refere ao fortalecimento de sua base tecnológica e produtiva. Como desdobramento, desenvolve um enfoque analítico e factual que relaciona a consolidação do CEIS no Brasil tanto como um vetor dinâmico do desenvolvimento industrial, gerando investimento, renda, emprego e inovações, quanto como elemento decisivo para a redução da vulnerabilidade e da dependência estrutural em saúde. Procura mostrar que seu fortalecimento e direcionamento para as necessidades sociais é parte essencial da construção de um Estado de Bem-Estar Social no Brasi.

Analysis of the discrepancies identified during medication reconciliation on patient admission in cardiology units: a descriptive study.

PubMed

Lombardi, Natália Fracaro; Mendes, Antonio Eduardo Matoso; Lucchetta, Rosa Camila; Reis, Wálleri Christini Torelli; Fávero, Maria Luiza Drechsel; Correr, Cassyano Januário

2016-08-15

this observational study aimed to describe the discrepancies identified during medication reconciliation on patient admission to cardiology units in a large hospital. the medication history of patients was collected within 48 hours after admission, and intentional and unintentional discrepancies were classified as omission, duplication, dose, frequency, timing, and route of drug administration. most of the patients evaluated were women (58.0%) with a mean age of 59 years, and 75.5% of the patients had a Charlson comorbidity index score between 1 and 3. Of the 117 discrepancies found, 50.4% were unintentional. Of these, 61.0% involved omission, 18.6% involved dosage, 18.6% involved timing, and 1.7% involved the route of drug administration. this study revealed a high prevalence of discrepancies, most of which were related to omissions, and 50% were unintentional. These results reveal the number of drugs that are not reincorporated into the treatment of patients, which can have important clinical consequences. este estudo observacional teve como objetivo descrever discrepâncias encontradas na realização de conciliação medicamentosa de pacientes admitidos em unidades de cardiologia de um hospital de grande porte. a história de medicação dos pacientes foi coletada dentro de 48h após a admissão, e as discrepâncias, identificadas como intencionais ou não intencionais, foram classificadas como de: omissão, duplicidade, dose, frequência, intervalo e via. a maioria dos pacientes incluídos pertençia ao sexo feminino (58,0%), com idade média de 59 anos, e com índice de comorbidades de Charlson entre 1 e 3 (75,5% dos casos). Das 117 discrepâncias encontradas, 50,4% foram não intencionais. Dessas, 61,0% foram de omissão, 18,6% de dose, 18,6% de intervalo e 1,7% de via de administração. o estudo mostra a alta prevalência de discrepâncias, principalmente de omissão, sendo quase metade não intencionais. Esse dado remete ao número de medicamentos que não são reincorporados ao tratamento dos pacientes, podendo repercutir em consequências clínicas importantes. este estudio observacional tuvo como objetivo describir discrepancias encontradas en la realización de la conciliación medicamentosa de pacientes admitidos en unidades de cardiología de un hospital de gran porte. la historia de medicación de los pacientes fue recolectada dentro de 48h después de la admisión, y las discrepancias, identificadas como intencionales o no intencionales, fueron clasificadas como: omisión, duplicidad, dosis, frecuencia, intervalo y vía. la mayoría de los pacientes incluidos pertenecía al sexo femenino (58,0%), con edad promedio de 59 años, y con índice de comorbilidad de Charlson entre 1 y 3 (75,5% de los casos). De las 117 discrepancias encontradas, 50,4% fueron no intencionales. De estas, 61,0% fueron de omisión, 18,6% de dosis, 18,6% de intervalo y 1,7% de vía de administración. el estudio muestra la alta prevalencia de discrepancias, principalmente de omisión, siendo casi mitad de ellas no intencionales. Ese dato nos indica el número de medicamentos que no son reincorporados al tratamiento de los pacientes, lo que puede repercutir en consecuencias clínicas importantes.

Late Glacial to Holocene environmental variabilities: A new multi-proxy paleolimnological study of sedimentary sequences from Como (northern Italy)

NASA Astrophysics Data System (ADS)

Höbig, N.; Martinelli, E.; Motella, S.; Michetti, A. M.; Livio, F.; Tinner, W.; Reicherter, K.; Castelletti, L.

2012-04-01

Lake Como (northern Italy) is the deepest Italian lake, reaching a depth of about 425 m. The lambda-shaped lake expands about 45 km in NE-SW direction. Southwards of the hydrologically closed western branch, two sediment cores of 70 m (S1) and 65 m length (S2) were taken in the year 2005 close to the cathedral of Como (Piazza Verdi). The drilling sites are located in the middle of the Southern Alps, some 300 m from the present-day lakeshore. The cores provide the first detailed Late Glacial to Holocene multi-proxy record for the Lake Como basin. Our research is aimed at investigating the environmental and geological evolution of the Insubria Region. The multi-proxy study of the stratigraphic sequences contain geophysical, geotechnical, sedimentological, paleobotanical, and radiocarbon analyses. They have been performed for core S1 and are still in progress on core S2. With this data the working group focuses on two main issues. The first topic is the reconstruction of the natural and anthropogenic processes controlling the ground subsidence in the Como urban area (e.g., Comerci et al., 2007) and another aim is to reconstruct vegetation and land-use dynamics. In particular, 150 samples of vegetal macroremains have been collected in the palustrine deposits along S1 core, down to 31,00 m. Below this depth (dated 14C 12,496 ± 55 yr BP - 15,050 - 14,250 cal yr BP), the amount of plant macroremains in the sediment drops dramatically. The taxonomic determination was carried out on more than 800 macroremains. They are represented by fragments of wood, leaves, needles, seeds, fruits, mosses and tiny charcoals (Motella, 2009, unpublished PhD Thesis). Picea/Larix, Pinus sp., Juniperus with Betula, found in the deeper levels (30.80 - 30.00 m), are the first arboreal taxa that colonized the shores of Lake Como, and show that the reforestation began in this area about 16,000 years ago. During the early Holocene (25.10 m) Abies alba expanded and further upwards the sequence mixed deciduous forests became important. Preliminary results of palynological analyses for a section of the core S2 (35.04 - 18.12 m), show Late Glacial sediments in the depth of 35.04 - 31.16 m, due to vegetation changes related to natural climatic variability, with an alternation of communities typical of cold (Poaceae, Artemisia, Juniperus, Pinus and Betula) and temperate climates (e.g. Quercus). Later, during the Holocene, forests composed by mostly deciduous broadleaves and Abies alba expanded. During the mid and late Holocene human impact increased and modified vegetation. This is shown by the increase of herbs and heliofilous shrubs (26.51 m), typical of deforested spaces for fields and pastures. Human exploitation of wood is represented for example by the dramatic decline of Abies alba (24.97 m). Finally, the increase of Cerealia (19.39 m) is clearly related to intensified agricultural activities. The results of further paleobotanical and geophysical analyses which are in progress will be presented during the conference. Moreover, geochemical measurements (e.g., XRF) will be performed in future for core S2. Researches realized within the project of Italy-Switzerland Cooperation SITINET "Censimento, valorizzazione e messa in rete di siti geologici e archeologici" (Census, increase of value and computerization of geological and archaeological sites). Interreg IV A "Geo-Archeositi dell'Insubria" (Geo-Archaeosites of Insubria).

Subjective Probabilities in Household Surveys

PubMed Central

Hurd, Michael D.

2011-01-01

Subjective probabilities are now collected on a number of large household surveys with the objective of providing data to better understand inter-temporal decision making. Comparison of subjective probabilities with actual outcomes shows that the probabilities have considerable predictive power in situations where individuals have considerable private information such as survival and retirement. In contrast the subjective probability of a stock market gain varies greatly across individuals even though no one has private information and the outcome is the same for everyone. An explanation is that there is considerable variation in accessing and processing information. Further, the subjective probability of a stock market gain is considerably lower than historical averages, providing an explanation for the relatively low frequency of stock holding. An important research objective will be to understand how individuals form their subjective probabilities. PMID:21643535

Ensemble learning and model averaging for material identification in hyperspectral imagery

NASA Astrophysics Data System (ADS)

Basener, William F.

2017-05-01

In this paper we present a method for identifying the material contained in a pixel or region of pixels in a hyperspectral image. An identification process can be performed on a spectrum from an image from pixels that has been pre-determined to be of interest, generally comparing the spectrum from the image to spectra in an identification library. The metric for comparison used in this paper a Bayesian probability for each material. This probability can be computed either from Bayes' theorem applied to normal distributions for each library spectrum or using model averaging. Using probabilities has the advantage that the probabilities can be summed over spectra for any material class to obtain a class probability. For example, the probability that the spectrum of interest is a fabric is equal to the sum of all probabilities for fabric spectra in the library. We can do the same to determine the probability for a specific type of fabric, or any level of specificity contained in our library. Probabilities not only tell us which material is most likely, the tell us how confident we can be in the material presence; a probability close to 1 indicates near certainty of the presence of a material in the given class, and a probability close to 0.5 indicates that we cannot know if the material is present at the given level of specificity. This is much more informative than a detection score from a target detection algorithm or a label from a classification algorithm. In this paper we present results in the form of a hierarchical tree with probabilities for each node. We use Forest Radiance imagery with 159 bands.

Stochastic approach for an unbiased estimation of the probability of a successful separation in conventional chromatography and sequential elution liquid chromatography.

PubMed

Ennis, Erin J; Foley, Joe P

2016-07-15

A stochastic approach was utilized to estimate the probability of a successful isocratic or gradient separation in conventional chromatography for numbers of sample components, peak capacities, and saturation factors ranging from 2 to 30, 20-300, and 0.017-1, respectively. The stochastic probabilities were obtained under conditions of (i) constant peak width ("gradient" conditions) and (ii) peak width increasing linearly with time ("isocratic/constant N" conditions). The isocratic and gradient probabilities obtained stochastically were compared with the probabilities predicted by Martin et al. [Anal. Chem., 58 (1986) 2200-2207] and Davis and Stoll [J. Chromatogr. A, (2014) 128-142]; for a given number of components and peak capacity the same trend is always observed: probability obtained with the isocratic stochastic approach

Saccade selection when reward probability is dynamically manipulated using Markov chains

PubMed Central

Lovejoy, Lee P.; Krauzlis, Richard J.

2012-01-01

Markov chains (stochastic processes where probabilities are assigned based on the previous outcome) are commonly used to examine the transitions between behavioral states, such as those that occur during foraging or social interactions. However, relatively little is known about how well primates can incorporate knowledge about Markov chains into their behavior. Saccadic eye movements are an example of a simple behavior influenced by information about probability, and thus are good candidates for testing whether subjects can learn Markov chains. In addition, when investigating the influence of probability on saccade target selection, the use of Markov chains could provide an alternative method that avoids confounds present in other task designs. To investigate these possibilities, we evaluated human behavior on a task in which stimulus reward probabilities were assigned using a Markov chain. On each trial, the subject selected one of four identical stimuli by saccade; after selection, feedback indicated the rewarded stimulus. Each session consisted of 200–600 trials, and on some sessions, the reward magnitude varied. On sessions with a uniform reward, subjects (n = 6) learned to select stimuli at a frequency close to reward probability, which is similar to human behavior on matching or probability classification tasks. When informed that a Markov chain assigned reward probabilities, subjects (n = 3) learned to select the greatest reward probability more often, bringing them close to behavior that maximizes reward. On sessions where reward magnitude varied across stimuli, subjects (n = 6) demonstrated preferences for both greater reward probability and greater reward magnitude, resulting in a preference for greater expected value (the product of reward probability and magnitude). These results demonstrate that Markov chains can be used to dynamically assign probabilities that are rapidly exploited by human subjects during saccade target selection. PMID:18330552

Saccade selection when reward probability is dynamically manipulated using Markov chains.

PubMed

Nummela, Samuel U; Lovejoy, Lee P; Krauzlis, Richard J

2008-05-01

Markov chains (stochastic processes where probabilities are assigned based on the previous outcome) are commonly used to examine the transitions between behavioral states, such as those that occur during foraging or social interactions. However, relatively little is known about how well primates can incorporate knowledge about Markov chains into their behavior. Saccadic eye movements are an example of a simple behavior influenced by information about probability, and thus are good candidates for testing whether subjects can learn Markov chains. In addition, when investigating the influence of probability on saccade target selection, the use of Markov chains could provide an alternative method that avoids confounds present in other task designs. To investigate these possibilities, we evaluated human behavior on a task in which stimulus reward probabilities were assigned using a Markov chain. On each trial, the subject selected one of four identical stimuli by saccade; after selection, feedback indicated the rewarded stimulus. Each session consisted of 200-600 trials, and on some sessions, the reward magnitude varied. On sessions with a uniform reward, subjects (n = 6) learned to select stimuli at a frequency close to reward probability, which is similar to human behavior on matching or probability classification tasks. When informed that a Markov chain assigned reward probabilities, subjects (n = 3) learned to select the greatest reward probability more often, bringing them close to behavior that maximizes reward. On sessions where reward magnitude varied across stimuli, subjects (n = 6) demonstrated preferences for both greater reward probability and greater reward magnitude, resulting in a preference for greater expected value (the product of reward probability and magnitude). These results demonstrate that Markov chains can be used to dynamically assign probabilities that are rapidly exploited by human subjects during saccade target selection.

Convergence of Transition Probability Matrix in CLVMarkov Models

NASA Astrophysics Data System (ADS)

Permana, D.; Pasaribu, U. S.; Indratno, S. W.; Suprayogi, S.

2018-04-01

A transition probability matrix is an arrangement of transition probability from one states to another in a Markov chain model (MCM). One of interesting study on the MCM is its behavior for a long time in the future. The behavior is derived from one property of transition probabilty matrix for n steps. This term is called the convergence of the n-step transition matrix for n move to infinity. Mathematically, the convergence of the transition probability matrix is finding the limit of the transition matrix which is powered by n where n moves to infinity. The convergence form of the transition probability matrix is very interesting as it will bring the matrix to its stationary form. This form is useful for predicting the probability of transitions between states in the future. The method usually used to find the convergence of transition probability matrix is through the process of limiting the distribution. In this paper, the convergence of the transition probability matrix is searched using a simple concept of linear algebra that is by diagonalizing the matrix.This method has a higher level of complexity because it has to perform the process of diagonalization in its matrix. But this way has the advantage of obtaining a common form of power n of the transition probability matrix. This form is useful to see transition matrix before stationary. For example cases are taken from CLV model using MCM called Model of CLV-Markov. There are several models taken by its transition probability matrix to find its convergence form. The result is that the convergence of the matrix of transition probability through diagonalization has similarity with convergence with commonly used distribution of probability limiting method.

Emergencias

EPA Pesticide Factsheets

Aprenda cómo usted puede prepararse y recuperarse de los desastres naturales como los huracanes y las inundaciones, aceite informe y derrames de sustancias peligrosas, y cómo la EPA responde a derramar emergencia.

MOUNT ZIRKEL WILDERNESS AND VICINITY, COLORADO.

USGS Publications Warehouse

Snyder, George L.; Patten, Lowell L.

1984-01-01

Several areas of metallic and nonmetallic mineralization have been identified from surface occurrences within the Mount Zirkel Wilderness and vicinity, Colorado. Three areas of probable copper-lead-zinc-silver-gold resource potential, two areas of probable chrome-platinum resource potential, four areas of probable uranium-thorium resource potential, two areas of probable molybdenum resource potential, and one area of probable fluorspar potential were identified. No potential for fossil fuel or geothermal resources was identified.

On Equivalence between Critical Probabilities of Dynamic Gossip Protocol and Static Site Percolation

NASA Astrophysics Data System (ADS)

Ishikawa, Tetsuya; Hayakawa, Tomohisa

The relationship between the critical probability of gossip protocol on the square lattice and the critical probability of site percolation on the square lattice is discussed. Specifically, these two critical probabilities are analytically shown to be equal to each other. Furthermore, we present a way of evaluating the critical probability of site percolation by approximating the saturation of gossip protocol. Finally, we provide numerical results which support the theoretical analysis.

The Cognitive Substrate of Subjective Probability

ERIC Educational Resources Information Center

Nilsson, Hakan; Olsson, Henrik; Juslin, Peter

2005-01-01

The prominent cognitive theories of probability judgment were primarily developed to explain cognitive biases rather than to account for the cognitive processes in probability judgment. In this article the authors compare 3 major theories of the processes and representations in probability judgment: the representativeness heuristic, implemented as…

Cultural Differences in Young Adults' Perceptions of the Probability of Future Family Life Events.

PubMed

Speirs, Calandra; Huang, Vivian; Konnert, Candace

2017-09-01

Most young adults are exposed to family caregiving; however, little is known about their perceptions of their future caregiving activities such as the probability of becoming a caregiver for their parents or providing assistance in relocating to a nursing home. This study examined the perceived probability of these events among 182 young adults and the following predictors of their probability ratings: gender, ethnicity, work or volunteer experience, experiences with caregiving and nursing homes, expectations about these transitions, and filial piety. Results indicated that Asian or South Asian participants rated the probability of being a caregiver as significantly higher than Caucasian participants, and the probability of placing a parent in a nursing home as significantly lower. Filial piety was the strongest predictor of the probability of these life events, and it mediated the relationship between ethnicity and probability ratings. These findings indicate the significant role of filial piety in shaping perceptions of future life events.

The utility of Bayesian predictive probabilities for interim monitoring of clinical trials

PubMed Central

Connor, Jason T.; Ayers, Gregory D; Alvarez, JoAnn

2014-01-01

Background Bayesian predictive probabilities can be used for interim monitoring of clinical trials to estimate the probability of observing a statistically significant treatment effect if the trial were to continue to its predefined maximum sample size. Purpose We explore settings in which Bayesian predictive probabilities are advantageous for interim monitoring compared to Bayesian posterior probabilities, p-values, conditional power, or group sequential methods. Results For interim analyses that address prediction hypotheses, such as futility monitoring and efficacy monitoring with lagged outcomes, only predictive probabilities properly account for the amount of data remaining to be observed in a clinical trial and have the flexibility to incorporate additional information via auxiliary variables. Limitations Computational burdens limit the feasibility of predictive probabilities in many clinical trial settings. The specification of prior distributions brings additional challenges for regulatory approval. Conclusions The use of Bayesian predictive probabilities enables the choice of logical interim stopping rules that closely align with the clinical decision making process. PMID:24872363

Optimum space shuttle launch times relative to natural environment

NASA Technical Reports Server (NTRS)

King, R. L.

1977-01-01

Three sets of meteorological criteria were analyzed to determine the probabilities of favorable launch and landing conditions. Probabilities were computed for every 3 hours on a yearly basis using 14 years of weather data. These temporal probability distributions, applicable to the three sets of weather criteria encompassing benign, moderate and severe weather conditions, were computed for both Kennedy Space Center (KSC) and Edwards Air Force Base. In addition, conditional probabilities were computed for unfavorable weather conditions occurring after a delay which may or may not be due to weather conditions. Also, for KSC, the probabilities of favorable landing conditions at various times after favorable launch conditions have prevailed have been computed so that mission probabilities may be more accurately computed for those time periods when persistence strongly correlates weather conditions. Moreover, the probabilities and conditional probabilities of the occurrence of both favorable and unfavorable events for each individual criterion were computed to indicate the significance of each weather element to the overall result.

Maximum predictive power and the superposition principle

NASA Technical Reports Server (NTRS)

Summhammer, Johann

1994-01-01

In quantum physics the direct observables are probabilities of events. We ask how observed probabilities must be combined to achieve what we call maximum predictive power. According to this concept the accuracy of a prediction must only depend on the number of runs whose data serve as input for the prediction. We transform each probability to an associated variable whose uncertainty interval depends only on the amount of data and strictly decreases with it. We find that for a probability which is a function of two other probabilities maximum predictive power is achieved when linearly summing their associated variables and transforming back to a probability. This recovers the quantum mechanical superposition principle.

Reduction of cardiovascular risk after preeclampsia: the role of framing and perceived probability in modifying behavior.

PubMed

Bokslag, Anouk; Hermes, Wietske; de Groot, Christianne J M; Teunissen, Pim W

2016-11-01

To reduce cardiovascular risk after preeclampsia, we investigated the effect of framing, the perceived probability and its interaction, on the willingness to modify behavior. Participants scored their willingness to modify behavior on two cases with different probabilities of developing cardiovascular disease. Both cases were either presented as "chance of health" or "risk of disease". 165 questionnaires were analyzed. ANOVA revealed a significant effect of probability, non-significant effect of framing and a non-significant interaction between probability and framing. Perceived probability influences willingness to modify behavior to reduce cardiovascular risk after preeclampsia; framing and the interaction was not of influence.

The neural correlates of subjective utility of monetary outcome and probability weight in economic and in motor decision under risk

PubMed Central

Wu, Shih-Wei; Delgado, Mauricio R.; Maloney, Laurence T.

2011-01-01

In decision under risk, people choose between lotteries that contain a list of potential outcomes paired with their probabilities of occurrence. We previously developed a method for translating such lotteries to mathematically equivalent motor lotteries. The probability of each outcome in a motor lottery is determined by the subject’s noise in executing a movement. In this study, we used functional magnetic resonance imaging in humans to compare the neural correlates of monetary outcome and probability in classical lottery tasks where information about probability was explicitly communicated to the subjects and in mathematically equivalent motor lottery tasks where probability was implicit in the subjects’ own motor noise. We found that activity in the medial prefrontal cortex (mPFC) and the posterior cingulate cortex (PCC) quantitatively represent the subjective utility of monetary outcome in both tasks. For probability, we found that the mPFC significantly tracked the distortion of such information in both tasks. Specifically, activity in mPFC represents probability information but not the physical properties of the stimuli correlated with this information. Together, the results demonstrate that mPFC represents probability from two distinct forms of decision under risk. PMID:21677166

The neural correlates of subjective utility of monetary outcome and probability weight in economic and in motor decision under risk.

PubMed

Wu, Shih-Wei; Delgado, Mauricio R; Maloney, Laurence T

2011-06-15

In decision under risk, people choose between lotteries that contain a list of potential outcomes paired with their probabilities of occurrence. We previously developed a method for translating such lotteries to mathematically equivalent "motor lotteries." The probability of each outcome in a motor lottery is determined by the subject's noise in executing a movement. In this study, we used functional magnetic resonance imaging in humans to compare the neural correlates of monetary outcome and probability in classical lottery tasks in which information about probability was explicitly communicated to the subjects and in mathematically equivalent motor lottery tasks in which probability was implicit in the subjects' own motor noise. We found that activity in the medial prefrontal cortex (mPFC) and the posterior cingulate cortex quantitatively represent the subjective utility of monetary outcome in both tasks. For probability, we found that the mPFC significantly tracked the distortion of such information in both tasks. Specifically, activity in mPFC represents probability information but not the physical properties of the stimuli correlated with this information. Together, the results demonstrate that mPFC represents probability from two distinct forms of decision under risk.

Aggregate and individual replication probability within an explicit model of the research process.

PubMed

Miller, Jeff; Schwarz, Wolf

2011-09-01

We study a model of the research process in which the true effect size, the replication jitter due to changes in experimental procedure, and the statistical error of effect size measurement are all normally distributed random variables. Within this model, we analyze the probability of successfully replicating an initial experimental result by obtaining either a statistically significant result in the same direction or any effect in that direction. We analyze both the probability of successfully replicating a particular experimental effect (i.e., the individual replication probability) and the average probability of successful replication across different studies within some research context (i.e., the aggregate replication probability), and we identify the conditions under which the latter can be approximated using the formulas of Killeen (2005a, 2007). We show how both of these probabilities depend on parameters of the research context that would rarely be known in practice. In addition, we show that the statistical uncertainty associated with the size of an initial observed effect would often prevent accurate estimation of the desired individual replication probability even if these research context parameters were known exactly. We conclude that accurate estimates of replication probability are generally unattainable.

Statistical tests for whether a given set of independent, identically distributed draws comes from a specified probability density.

PubMed

Tygert, Mark

2010-09-21

We discuss several tests for determining whether a given set of independent and identically distributed (i.i.d.) draws does not come from a specified probability density function. The most commonly used are Kolmogorov-Smirnov tests, particularly Kuiper's variant, which focus on discrepancies between the cumulative distribution function for the specified probability density and the empirical cumulative distribution function for the given set of i.i.d. draws. Unfortunately, variations in the probability density function often get smoothed over in the cumulative distribution function, making it difficult to detect discrepancies in regions where the probability density is small in comparison with its values in surrounding regions. We discuss tests without this deficiency, complementing the classical methods. The tests of the present paper are based on the plain fact that it is unlikely to draw a random number whose probability is small, provided that the draw is taken from the same distribution used in calculating the probability (thus, if we draw a random number whose probability is small, then we can be confident that we did not draw the number from the same distribution used in calculating the probability).

Geophysical investigations of the Olonium Roman site (Northern Como Lake)

NASA Astrophysics Data System (ADS)

Arlsan, Ermanno; Biella, Giancarlo; Boniolo, Graziano; Caporusso, Donatella; de Franco, Roberto; Lozej, Alfredo; Veronese, Luigi

1999-03-01

The study area is located at S. Agata (Gera Lario), a small center at the northern end of Como Lake, near the junction of Valchiavenna and Valtellina Valleys. This site played a strategic role since ancient times, providing the control on the communications routes to both the Como Lake and the Spluga and Septimer alpine passes. Since the end of the last century archaeological findings are reported in literature, also supported, from the early XI century, by archival documents confirming the existence of the `Olonium' settlement, an administrative and fiscal center of primary importance, as well as a parish amongst the most influential in the Como Lake area. Within an area of 45,000 m 2 an electrical survey has been carried out in conjunction with magnetic and GPR investigations. These studies have indicated the presence of a number of sub-areas characterized by significant anomalies defined by the overlapping of the results obtained from two or more geophysical methods. In two of such sub-areas, excavation tests have been conducted, which have brought to light a number of archaeological findings of interest. In one of the two sub-areas, which is characterized by the superimposition of electrical and radar anomalies, a deposit of large pebbles has been found. The origin of this deposit has not been ascertained, whether it is of fluvial origin, related to the deviation of the Adda river in the Pian di Spagna region in Roman times, or it is part of reclamation works, still of Roman times, of paleolacustrine marshes. The overlapping stratigraphy, however, suggests the development of fluvial channels between Roman and Low-Medieval times. In the other sub-area, excavations were carried out on sites defined by electrical and radar anomalies, and confirmed by the results from magnetic survey. The excavations brought to light, below the fluvial deposits, a large medieval edifice, which could be identified as the S. Stefano church abandoned in 1444. The church is built on earlier structures, amongst which an apse with a single aisle has been interpreted as a paleochristian sacellum.

The Reflective Abstraction Theory and the History of Astronomy. (Spanish Title: La Teoría de la Abstracción Reflexionante y la Historia de la Astronomía.) A Teoria da Abstração Reflexionante e a História da Astronomia.

NASA Astrophysics Data System (ADS)

Chiesa Bartelmebs, Roberta; Batista Siqueira Harres, João; da Silva, João Alberto

2014-12-01

This work is presented as a theoretical essay on some facts from the history of astronomy analyzed according to the theory of reflective abstraction developed by Jean Piaget and collaborators (1970). Its aim is to understand the reasons that led to different astronomers, at the same historical period and culture, to "see" quite different evidences about the same phenomenon. In addition, we intend to facilitate the understanding of science as a human construction, subject to a time epoch and the ways of understanding of each scientist. Este trabajo se presenta como un ensayo teórico sobre algunos hechos históricos de la astronomía, analizados según la teoría de la abstracción reflexionante de Jean Piaget y sus colaboradores (1970). Se trata de comprender los motivos que llevaran a distintos astrónomos, de una misma época histórica y cultural, a "ver" diferentes evidencias sobre un mismo fenómeno. Además, se intenta posibilitar la comprensión de la ciencia como construcción humana, la cual es condicionada por su momento histórico y por las creencias y las formas de entender de los científicos. Este trabalho configura-se como um ensaio teórico a respeito de alguns fatos da história da astronomia analisados segundo a teoria da abstração reflexionante elaborada por Jean Piaget e seus colaboradores (1970). Trata-se de compreender os motivos que levaram diferentes astrônomos, da mesma época histórica e cultural, a "enxergarem" evidências tão diferentes sobre um mesmo fenômeno. Além disso, pretendemos possibilitar a compreensão das Ciências como construção humana, condicionadas a uma época e às crenças e os modos de compreender de cada cientista.

Variación temporal de las constantes fundamentales

NASA Astrophysics Data System (ADS)

Landau, S. J.; Vucetich, H.

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

Trait mindfulness, reasons for living and general symptom severity as predictors of suicide probability in males with substance abuse or dependence.

PubMed

Mohammadkhani, Parvaneh; Khanipour, Hamid; Azadmehr, Hedieh; Mobramm, Ardeshir; Naseri, Esmaeil

2015-01-01

The aim of this study was to evaluate suicide probability in Iranian males with substance abuse or dependence disorder and to investigate the predictors of suicide probability based on trait mindfulness, reasons for living and severity of general psychiatric symptoms. Participants were 324 individuals with substance abuse or dependence in an outpatient setting and prison. Reasons for living questionnaire, Mindfulness Attention Awareness Scale and Suicide probability Scale were used as instruments. Sample was selected based on convenience sampling method. Data were analyzed using SPSS and AMOS. The life-time prevalence of suicide attempt in the outpatient setting was35% and it was 42% in the prison setting. Suicide probability in the prison setting was significantly higher than in the outpatient setting (p<0.001). The severity of general symptom strongly correlated with suicide probability. Trait mindfulness, not reasons for living beliefs, had a mediating effect in the relationship between the severity of general symptoms and suicide probability. Fear of social disapproval, survival and coping beliefs and child-related concerns significantly predicted suicide probability (p<0.001). It could be suggested that trait mindfulness was more effective in preventing suicide probability than beliefs about reasons for living in individuals with substance abuse or dependence disorders. The severity of general symptom should be regarded as an important risk factor of suicide probability.

Decision analysis with cumulative prospect theory.

PubMed

Bayoumi, A M; Redelmeier, D A

2000-01-01

Individuals sometimes express preferences that do not follow expected utility theory. Cumulative prospect theory adjusts for some phenomena by using decision weights rather than probabilities when analyzing a decision tree. The authors examined how probability transformations from cumulative prospect theory might alter a decision analysis of a prophylactic therapy in AIDS, eliciting utilities from patients with HIV infection (n = 75) and calculating expected outcomes using an established Markov model. They next focused on transformations of three sets of probabilities: 1) the probabilities used in calculating standard-gamble utility scores; 2) the probabilities of being in discrete Markov states; 3) the probabilities of transitioning between Markov states. The same prophylaxis strategy yielded the highest quality-adjusted survival under all transformations. For the average patient, prophylaxis appeared relatively less advantageous when standard-gamble utilities were transformed. Prophylaxis appeared relatively more advantageous when state probabilities were transformed and relatively less advantageous when transition probabilities were transformed. Transforming standard-gamble and transition probabilities simultaneously decreased the gain from prophylaxis by almost half. Sensitivity analysis indicated that even near-linear probability weighting transformations could substantially alter quality-adjusted survival estimates. The magnitude of benefit estimated in a decision-analytic model can change significantly after using cumulative prospect theory. Incorporating cumulative prospect theory into decision analysis can provide a form of sensitivity analysis and may help describe when people deviate from expected utility theory.

The analysis of probability task completion; Taxonomy of probabilistic thinking-based across gender in elementary school students

NASA Astrophysics Data System (ADS)

Sari, Dwi Ivayana; Budayasa, I. Ketut; Juniati, Dwi

2017-08-01

Formulation of mathematical learning goals now is not only oriented on cognitive product, but also leads to cognitive process, which is probabilistic thinking. Probabilistic thinking is needed by students to make a decision. Elementary school students are required to develop probabilistic thinking as foundation to learn probability at higher level. A framework of probabilistic thinking of students had been developed by using SOLO taxonomy, which consists of prestructural probabilistic thinking, unistructural probabilistic thinking, multistructural probabilistic thinking and relational probabilistic thinking. This study aimed to analyze of probability task completion based on taxonomy of probabilistic thinking. The subjects were two students of fifth grade; boy and girl. Subjects were selected by giving test of mathematical ability and then based on high math ability. Subjects were given probability tasks consisting of sample space, probability of an event and probability comparison. The data analysis consisted of categorization, reduction, interpretation and conclusion. Credibility of data used time triangulation. The results was level of boy's probabilistic thinking in completing probability tasks indicated multistructural probabilistic thinking, while level of girl's probabilistic thinking in completing probability tasks indicated unistructural probabilistic thinking. The results indicated that level of boy's probabilistic thinking was higher than level of girl's probabilistic thinking. The results could contribute to curriculum developer in developing probability learning goals for elementary school students. Indeed, teachers could teach probability with regarding gender difference.

Inverse sequential detection of parameter changes in developing time series

NASA Technical Reports Server (NTRS)

Radok, Uwe; Brown, Timothy J.

1992-01-01

Progressive values of two probabilities are obtained for parameter estimates derived from an existing set of values and from the same set enlarged by one or more new values, respectively. One probability is that of erroneously preferring the second of these estimates for the existing data ('type 1 error'), while the second probability is that of erroneously accepting their estimates for the enlarged test ('type 2 error'). A more stable combined 'no change' probability which always falls between 0.5 and 0 is derived from the (logarithmic) width of the uncertainty region of an equivalent 'inverted' sequential probability ratio test (SPRT, Wald 1945) in which the error probabilities are calculated rather than prescribed. A parameter change is indicated when the compound probability undergoes a progressive decrease. The test is explicitly formulated and exemplified for Gaussian samples.

Tracking the Sensory Environment: An ERP Study of Probability and Context Updating in ASD

PubMed Central

Westerfield, Marissa A.; Zinni, Marla; Vo, Khang; Townsend, Jeanne

2014-01-01

We recorded visual event-related brain potentials (ERPs) from 32 adult male participants (16 high-functioning participants diagnosed with Autism Spectrum Disorder (ASD) and 16 control participants, ranging in age from 18–53 yrs) during a three-stimulus oddball paradigm. Target and non-target stimulus probability was varied across three probability conditions, whereas the probability of a third non-target stimulus was held constant in all conditions. P3 amplitude to target stimuli was more sensitive to probability in ASD than in TD participants, whereas P3 amplitude to non-target stimuli was less responsive to probability in ASD participants. This suggests that neural responses to changes in event probability are attention-dependant in high-functioning ASD. The implications of these findings for higher-level behaviors such as prediction and planning are discussed. PMID:24488156

Comparison of three Bayesian methods to estimate posttest probability in patients undergoing exercise stress testing

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

Morise, A.P.; Duval, R.D.

To determine whether recent refinements in Bayesian methods have led to improved diagnostic ability, 3 methods using Bayes' theorem and the independence assumption for estimating posttest probability after exercise stress testing were compared. Each method differed in the number of variables considered in the posttest probability estimate (method A = 5, method B = 6 and method C = 15). Method C is better known as CADENZA. There were 436 patients (250 men and 186 women) who underwent stress testing (135 had concurrent thallium scintigraphy) followed within 2 months by coronary arteriography. Coronary artery disease ((CAD), at least 1 vesselmore » with greater than or equal to 50% diameter narrowing) was seen in 169 (38%). Mean pretest probabilities using each method were not different. However, the mean posttest probabilities for CADENZA were significantly greater than those for method A or B (p less than 0.0001). Each decile of posttest probability was compared to the actual prevalence of CAD in that decile. At posttest probabilities less than or equal to 20%, there was underestimation of CAD. However, at posttest probabilities greater than or equal to 60%, there was overestimation of CAD by all methods, especially CADENZA. Comparison of sensitivity and specificity at every fifth percentile of posttest probability revealed that CADENZA was significantly more sensitive and less specific than methods A and B. Therefore, at lower probability thresholds, CADENZA was a better screening method. However, methods A or B still had merit as a means to confirm higher probabilities generated by CADENZA (especially greater than or equal to 60%).« less

Clinicians' perceptions of the value of ventilation-perfusion scans.

PubMed

Siegel, Alan; Holtzman, Stephen R; Bettmann, Michael A; Black, William C

2004-07-01

The goal of this investigation was to understand clinicians' perceptions of the probability of pulmonary embolism as a function of V/Q scan results of normal, low, intermediate, and high probability. A questionnaire was developed and distributed to 429 clinicians at a single academic medical center. The response rate was 44% (188 of 429). The questions included level of training, specialty, probability of PE given 1 of the 4 V/Q scan results, and estimations of the charges for V/Q scanning and pulmonary angiography, and estimations of the risks of pulmonary angiography. The medians and ranges for the probability of pulmonary embolism given a normal, low, intermediate, and high probability V/Q scan result were 2.5% (0-30), 12.5% (0.5-52.5), 41.25% (5-75), and 85% (5-100), respectively. Eleven percent (21 of 188) of the respondents listed the probability of PE in patients with a low probability V/Q scan as being 5% or less, and 33% (62 of 188) listed the probability of PE given an intermediate probability scan as 50% or greater. The majority correctly identified the rate of serious complications of pulmonary arteriography, but many respondents underestimated the charge for V/Q scans and pulmonary arteriography. A substantial minority of clinicians do not understand the probability of pulmonary embolism in patients with low and intermediate probability ventilation-perfusion scans. More quantitative reporting of results is recommended. This could be particularly important because VQ scans are used less frequently but are still needed in certain clinical situations.

Bayesian probability analysis: a prospective demonstration of its clinical utility in diagnosing coronary disease

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

Detrano, R.; Yiannikas, J.; Salcedo, E.E.

One hundred fifty-four patients referred for coronary arteriography were prospectively studied with stress electrocardiography, stress thallium scintigraphy, cine fluoroscopy (for coronary calcifications), and coronary angiography. Pretest probabilities of coronary disease were determined based on age, sex, and type of chest pain. These and pooled literature values for the conditional probabilities of test results based on disease state were used in Bayes theorem to calculate posttest probabilities of disease. The results of the three noninvasive tests were compared for statistical independence, a necessary condition for their simultaneous use in Bayes theorem. The test results were found to demonstrate pairwise independence inmore » patients with and those without disease. Some dependencies that were observed between the test results and the clinical variables of age and sex were not sufficient to invalidate application of the theorem. Sixty-eight of the study patients had at least one major coronary artery obstruction of greater than 50%. When these patients were divided into low-, intermediate-, and high-probability subgroups according to their pretest probabilities, noninvasive test results analyzed by Bayesian probability analysis appropriately advanced 17 of them by at least one probability subgroup while only seven were moved backward. Of the 76 patients without disease, 34 were appropriately moved into a lower probability subgroup while 10 were incorrectly moved up. We conclude that posttest probabilities calculated from Bayes theorem more accurately classified patients with and without disease than did pretest probabilities, thus demonstrating the utility of the theorem in this application.« less

The predictive value of chronic kidney disease for assessing cardiovascular events under consideration of pretest probability for coronary artery disease in patients who underwent stress myocardial perfusion imaging.

PubMed

Furuhashi, Tatsuhiko; Moroi, Masao; Joki, Nobuhiko; Hase, Hiroki; Masai, Hirofumi; Kunimasa, Taeko; Fukuda, Hiroshi; Sugi, Kaoru

2013-02-01

Pretest probability of coronary artery disease (CAD) facilitates diagnosis and risk stratification of CAD. Stress myocardial perfusion imaging (MPI) and chronic kidney disease (CKD) are established major predictors of cardiovascular events. However, the role of CKD to assess pretest probability of CAD has been unclear. This study evaluates the role of CKD to assess the predictive value of cardiovascular events under consideration of pretest probability in patients who underwent stress MPI. Patients with no history of CAD underwent stress MPI (n = 310; male = 166; age = 70; CKD = 111; low/intermediate/high pretest probability = 17/194/99) and were followed for 24 months. Cardiovascular events included cardiac death and nonfatal acute coronary syndrome. Cardiovascular events occurred in 15 of the 310 patients (4.8 %), but not in those with low pretest probability which included 2 CKD patients. In patients with intermediate to high pretest probability (n = 293), multivariate Cox regression analysis identified only CKD [hazard ratio (HR) = 4.88; P = 0.022) and summed stress score of stress MPI (HR = 1.50; P < 0.001) as independent and significant predictors of cardiovascular events. Cardiovascular events were not observed in patients with low pretest probability. In patients with intermediate to high pretest probability, CKD and stress MPI are independent predictors of cardiovascular events considering the pretest probability of CAD in patients with no history of CAD. In assessing pretest probability of CAD, CKD might be an important factor for assessing future cardiovascular prognosis.

Neural Encoding and Integration of Learned Probabilistic Sequences in Avian Sensory-Motor Circuitry

PubMed Central

Brainard, Michael S.

2013-01-01

Many complex behaviors, such as human speech and birdsong, reflect a set of categorical actions that can be flexibly organized into variable sequences. However, little is known about how the brain encodes the probabilities of such sequences. Behavioral sequences are typically characterized by the probability of transitioning from a given action to any subsequent action (which we term “divergence probability”). In contrast, we hypothesized that neural circuits might encode the probability of transitioning to a given action from any preceding action (which we term “convergence probability”). The convergence probability of repeatedly experienced sequences could naturally become encoded by Hebbian plasticity operating on the patterns of neural activity associated with those sequences. To determine whether convergence probability is encoded in the nervous system, we investigated how auditory-motor neurons in vocal premotor nucleus HVC of songbirds encode different probabilistic characterizations of produced syllable sequences. We recorded responses to auditory playback of pseudorandomly sequenced syllables from the bird's repertoire, and found that variations in responses to a given syllable could be explained by a positive linear dependence on the convergence probability of preceding sequences. Furthermore, convergence probability accounted for more response variation than other probabilistic characterizations, including divergence probability. Finally, we found that responses integrated over >7–10 syllables (∼700–1000 ms) with the sign, gain, and temporal extent of integration depending on convergence probability. Our results demonstrate that convergence probability is encoded in sensory-motor circuitry of the song-system, and suggest that encoding of convergence probability is a general feature of sensory-motor circuits. PMID:24198363

Warship Combat System Selection Methodology Based on Discrete Event Simulation

DTIC Science & Technology

2010-09-01

Platform (from Spanish) PD Damage Probability xiv PHit Hit Probability PKill Kill Probability RSM Response Surface Model SAM Surface-Air Missile...such a large target allows an assumption that the probability of a hit ( PHit ) is one. This structure can be considered as a bridge; therefore, the

Uncertainty plus Prior Equals Rational Bias: An Intuitive Bayesian Probability Weighting Function

ERIC Educational Resources Information Center

Fennell, John; Baddeley, Roland

2012-01-01

Empirical research has shown that when making choices based on probabilistic options, people behave as if they overestimate small probabilities, underestimate large probabilities, and treat positive and negative outcomes differently. These distortions have been modeled using a nonlinear probability weighting function, which is found in several…

Teaching Probabilities and Statistics to Preschool Children

ERIC Educational Resources Information Center

Pange, Jenny

2003-01-01

This study considers the teaching of probabilities and statistics to a group of preschool children using traditional classroom activities and Internet games. It was clear from this study that children can show a high level of understanding of probabilities and statistics, and demonstrate high performance in probability games. The use of Internet…

Students' Understanding of Conditional Probability on Entering University

ERIC Educational Resources Information Center

Reaburn, Robyn

2013-01-01

An understanding of conditional probability is essential for students of inferential statistics as it is used in Null Hypothesis Tests. Conditional probability is also used in Bayes' theorem, in the interpretation of medical screening tests and in quality control procedures. This study examines the understanding of conditional probability of…

Pig Data and Bayesian Inference on Multinomial Probabilities

ERIC Educational Resources Information Center

Kern, John C.

2006-01-01

Bayesian inference on multinomial probabilities is conducted based on data collected from the game Pass the Pigs[R]. Prior information on these probabilities is readily available from the instruction manual, and is easily incorporated in a Dirichlet prior. Posterior analysis of the scoring probabilities quantifies the discrepancy between empirical…

Probabilistic Cloning of Three Real States with Optimal Success Probabilities

NASA Astrophysics Data System (ADS)

Rui, Pin-shu

2017-06-01

We investigate the probabilistic quantum cloning (PQC) of three real states with average probability distribution. To get the analytic forms of the optimal success probabilities we assume that the three states have only two pairwise inner products. Based on the optimal success probabilities, we derive the explicit form of 1 →2 PQC for cloning three real states. The unitary operation needed in the PQC process is worked out too. The optimal success probabilities are also generalized to the M→ N PQC case.

A short note on probability in clinical medicine.

PubMed

Upshur, Ross E G

2013-06-01

Probability claims are ubiquitous in clinical medicine, yet exactly how clinical events relate to interpretations of probability has been not been well explored. This brief essay examines the major interpretations of probability and how these interpretations may account for the probabilistic nature of clinical events. It is argued that there are significant problems with the unquestioned application of interpretation of probability to clinical events. The essay concludes by suggesting other avenues to understand uncertainty in clinical medicine. © 2013 John Wiley & Sons Ltd.

The mediating effect of psychosocial factors on suicidal probability among adolescents.

PubMed

Hur, Ji-Won; Kim, Won-Joong; Kim, Yong-Ku

2011-01-01

Suicidal probability is an actual tendency including negative self-evaluation, hopelessness, suicidal ideation, and hostility. The purpose of this study was to examine the role of psychosocial variances in the suicidal probability of adolescents, especially the role of mediating variance. This study investigated the mediating effects of psychosocial factors such as depression, anxiety, self-esteem, stress, and social support on the suicidal probability among 1,586 adolescents attending middle and high schools in the Kyunggi Province area of South Korea. The relationship between depression and anxiety/suicidal probability was mediated by both social resources and self-esteem. Furthermore, the influence of social resources was mediated by interpersonal and achievement stress as well as self-esteem. This study suggests that suicidal probability in adolescents has various relationships, including mediating relations, with several psychosocial factors. The interventions on suicidal probability in adolescents should focus on social factors as well as clinical symptoms.

p-adic stochastic hidden variable model

NASA Astrophysics Data System (ADS)

Khrennikov, Andrew

1998-03-01

We propose stochastic hidden variables model in which hidden variables have a p-adic probability distribution ρ(λ) and at the same time conditional probabilistic distributions P(U,λ), U=A,A',B,B', are ordinary probabilities defined on the basis of the Kolmogorov measure-theoretical axiomatics. A frequency definition of p-adic probability is quite similar to the ordinary frequency definition of probability. p-adic frequency probability is defined as the limit of relative frequencies νn but in the p-adic metric. We study a model with p-adic stochastics on the level of the hidden variables description. But, of course, responses of macroapparatuses have to be described by ordinary stochastics. Thus our model describes a mixture of p-adic stochastics of the microworld and ordinary stochastics of macroapparatuses. In this model probabilities for physical observables are the ordinary probabilities. At the same time Bell's inequality is violated.

Bivariate normal, conditional and rectangular probabilities: A computer program with applications

NASA Technical Reports Server (NTRS)

Swaroop, R.; Brownlow, J. D.; Ashwworth, G. R.; Winter, W. R.

1980-01-01

Some results for the bivariate normal distribution analysis are presented. Computer programs for conditional normal probabilities, marginal probabilities, as well as joint probabilities for rectangular regions are given: routines for computing fractile points and distribution functions are also presented. Some examples from a closed circuit television experiment are included.

Training in Small Business Retailing: Testing Human Capital Theory.

ERIC Educational Resources Information Center

Barcala, Marta Fernandez; Perez, Maria Jose Sanzo; Gutierrez, Juan Antonio Trespalacios

1999-01-01

Looks at four models of training demand: (1) probability of attending training in the near future; (2) probability of having attended training in the past; (3) probability of being willing to follow multimedia and correspondence courses; and (4) probability of repeating the experience of attending another training course in the near future.…

Pre-Service Teachers' Conceptions of Probability

ERIC Educational Resources Information Center

Odafe, Victor U.

2011-01-01

Probability knowledge and skills are needed in science and in making daily decisions that are sometimes made under uncertain conditions. Hence, there is the need to ensure that the pre-service teachers of our children are well prepared to teach probability. Pre-service teachers' conceptions of probability are identified, and ways of helping them…

The Efficacy of Using Diagrams When Solving Probability Word Problems in College

ERIC Educational Resources Information Center

Beitzel, Brian D.; Staley, Richard K.

2015-01-01

Previous experiments have shown a deleterious effect of visual representations on college students' ability to solve total- and joint-probability word problems. The present experiments used conditional-probability problems, known to be more difficult than total- and joint-probability problems. The diagram group was instructed in how to use tree…

An Alternative Version of Conditional Probabilities and Bayes' Rule: An Application of Probability Logic

ERIC Educational Resources Information Center

Satake, Eiki; Amato, Philip P.

2008-01-01

This paper presents an alternative version of formulas of conditional probabilities and Bayes' rule that demonstrate how the truth table of elementary mathematical logic applies to the derivations of the conditional probabilities of various complex, compound statements. This new approach is used to calculate the prior and posterior probabilities…

Introduction to Probability, Part 1 - Basic Concepts. Student Text. Revised Edition.

ERIC Educational Resources Information Center

Blakeslee, David W.; And Others

This book is designed to introduce the reader to some fundamental ideas about probability. The mathematical theory of probability plays an increasingly important role in science, government, industry, business, and economics. An understanding of the basic concepts of probability is essential for the study of statistical methods that are widely…

You Say "Probable" and I Say "Likely": Improving Interpersonal Communication With Verbal Probability Phrases

ERIC Educational Resources Information Center

Karelitz, Tzur M.; Budescu, David V.

2004-01-01

When forecasters and decision makers describe uncertain events using verbal probability terms, there is a risk of miscommunication because people use different probability phrases and interpret them in different ways. In an effort to facilitate the communication process, the authors investigated various ways of converting the forecasters' verbal…

What's Missing in Teaching Probability and Statistics: Building Cognitive Schema for Understanding Random Phenomena

ERIC Educational Resources Information Center

Kuzmak, Sylvia

2016-01-01

Teaching probability and statistics is more than teaching the mathematics itself. Historically, the mathematics of probability and statistics was first developed through analyzing games of chance such as the rolling of dice. This article makes the case that the understanding of probability and statistics is dependent upon building a…

A Comprehensive Probability Project for the Upper Division One-Semester Probability Course Using Yahtzee

ERIC Educational Resources Information Center

Wilson, Jason; Lawman, Joshua; Murphy, Rachael; Nelson, Marissa

2011-01-01

This article describes a probability project used in an upper division, one-semester probability course with third-semester calculus and linear algebra prerequisites. The student learning outcome focused on developing the skills necessary for approaching project-sized math/stat application problems. These skills include appropriately defining…

The Influence of Phonotactic Probability on Nonword Repetition and Fast Mapping in 3-Year-Olds With a History of Expressive Language Delay.

PubMed

MacRoy-Higgins, Michelle; Dalton, Kevin Patrick

2015-12-01

The purpose of this study was to examine the influence of phonotactic probability on sublexical (phonological) and lexical representations in 3-year-olds who had a history of being late talkers in comparison with their peers with typical language development. Ten 3-year-olds who were late talkers and 10 age-matched typically developing controls completed nonword repetition and fast mapping tasks; stimuli for both experimental procedures differed in phonotactic probability. Both participant groups repeated nonwords containing high phonotactic probability sequences more accurately than nonwords containing low phonotactic probability sequences. Participants with typical language showed an early advantage for fast mapping high phonotactic probability words; children who were late talkers required more exposures to the novel words to show the same advantage for fast mapping high phonotactic probability words. Children who were late talkers showed similar sensitivities to phonotactic probability in nonword repetition and word learning when compared with their peers with no history of language delay. However, word learning in children who were late talkers appeared to be slower when compared with their peers.

Assessment of source probabilities for potential tsunamis affecting the U.S. Atlantic coast

USGS Publications Warehouse

Geist, E.L.; Parsons, T.

2009-01-01

Estimating the likelihood of tsunamis occurring along the U.S. Atlantic coast critically depends on knowledge of tsunami source probability. We review available information on both earthquake and landslide probabilities from potential sources that could generate local and transoceanic tsunamis. Estimating source probability includes defining both size and recurrence distributions for earthquakes and landslides. For the former distribution, source sizes are often distributed according to a truncated or tapered power-law relationship. For the latter distribution, sources are often assumed to occur in time according to a Poisson process, simplifying the way tsunami probabilities from individual sources can be aggregated. For the U.S. Atlantic coast, earthquake tsunami sources primarily occur at transoceanic distances along plate boundary faults. Probabilities for these sources are constrained from previous statistical studies of global seismicity for similar plate boundary types. In contrast, there is presently little information constraining landslide probabilities that may generate local tsunamis. Though there is significant uncertainty in tsunami source probabilities for the Atlantic, results from this study yield a comparative analysis of tsunami source recurrence rates that can form the basis for future probabilistic analyses.

A probable probability distribution of a series nonequilibrium states in a simple system out of equilibrium

NASA Astrophysics Data System (ADS)

Gao, Haixia; Li, Ting; Xiao, Changming

2016-05-01

When a simple system is in its nonequilibrium state, it will shift to its equilibrium state. Obviously, in this process, there are a series of nonequilibrium states. With the assistance of Bayesian statistics and hyperensemble, a probable probability distribution of these nonequilibrium states can be determined by maximizing the hyperensemble entropy. It is known that the largest probability is the equilibrium state, and the far a nonequilibrium state is away from the equilibrium one, the smaller the probability will be, and the same conclusion can also be obtained in the multi-state space. Furthermore, if the probability stands for the relative time the corresponding nonequilibrium state can stay, then the velocity of a nonequilibrium state returning back to its equilibrium can also be determined through the reciprocal of the derivative of this probability. It tells us that the far away the state from the equilibrium is, the faster the returning velocity will be; if the system is near to its equilibrium state, the velocity will tend to be smaller and smaller, and finally tends to 0 when it gets the equilibrium state.

Electrofishing capture probability of smallmouth bass in streams

USGS Publications Warehouse

Dauwalter, D.C.; Fisher, W.L.

2007-01-01

Abundance estimation is an integral part of understanding the ecology and advancing the management of fish populations and communities. Mark-recapture and removal methods are commonly used to estimate the abundance of stream fishes. Alternatively, abundance can be estimated by dividing the number of individuals sampled by the probability of capture. We conducted a mark-recapture study and used multiple repeated-measures logistic regression to determine the influence of fish size, sampling procedures, and stream habitat variables on the cumulative capture probability for smallmouth bass Micropterus dolomieu in two eastern Oklahoma streams. The predicted capture probability was used to adjust the number of individuals sampled to obtain abundance estimates. The observed capture probabilities were higher for larger fish and decreased with successive electrofishing passes for larger fish only. Model selection suggested that the number of electrofishing passes, fish length, and mean thalweg depth affected capture probabilities the most; there was little evidence for any effect of electrofishing power density and woody debris density on capture probability. Leave-one-out cross validation showed that the cumulative capture probability model predicts smallmouth abundance accurately. ?? Copyright by the American Fisheries Society 2007.

Method- and species-specific detection probabilities of fish occupancy in Arctic lakes: Implications for design and management

USGS Publications Warehouse

Haynes, Trevor B.; Rosenberger, Amanda E.; Lindberg, Mark S.; Whitman, Matthew; Schmutz, Joel A.

2013-01-01

Studies examining species occurrence often fail to account for false absences in field sampling. We investigate detection probabilities of five gear types for six fish species in a sample of lakes on the North Slope, Alaska. We used an occupancy modeling approach to provide estimates of detection probabilities for each method. Variation in gear- and species-specific detection probability was considerable. For example, detection probabilities for the fyke net ranged from 0.82 (SE = 0.05) for least cisco (Coregonus sardinella) to 0.04 (SE = 0.01) for slimy sculpin (Cottus cognatus). Detection probabilities were also affected by site-specific variables such as depth of the lake, year, day of sampling, and lake connection to a stream. With the exception of the dip net and shore minnow traps, each gear type provided the highest detection probability of at least one species. Results suggest that a multimethod approach may be most effective when attempting to sample the entire fish community of Arctic lakes. Detection probability estimates will be useful for designing optimal fish sampling and monitoring protocols in Arctic lakes.

Off-diagonal long-range order, cycle probabilities, and condensate fraction in the ideal Bose gas.

PubMed

Chevallier, Maguelonne; Krauth, Werner

2007-11-01

We discuss the relationship between the cycle probabilities in the path-integral representation of the ideal Bose gas, off-diagonal long-range order, and Bose-Einstein condensation. Starting from the Landsberg recursion relation for the canonic partition function, we use elementary considerations to show that in a box of size L3 the sum of the cycle probabilities of length k>L2 equals the off-diagonal long-range order parameter in the thermodynamic limit. For arbitrary systems of ideal bosons, the integer derivative of the cycle probabilities is related to the probability of condensing k bosons. We use this relation to derive the precise form of the pik in the thermodynamic limit. We also determine the function pik for arbitrary systems. Furthermore, we use the cycle probabilities to compute the probability distribution of the maximum-length cycles both at T=0, where the ideal Bose gas reduces to the study of random permutations, and at finite temperature. We close with comments on the cycle probabilities in interacting Bose gases.

Competencias en ética biocéntrica

PubMed Central

Stepke, Fernando Lolas

2013-01-01

Resumen Este artículo explora el origen y la conceptualización de la bioética en tanto ética biocéntrica, definida por el pionero Fritz Jahr como un imperativo hipotético que llama a respetar la vida en todas sus formas. Tras describirla como proceso social, procedimiento técnico y producto académico, se enumeran y comentan algunas competencias que debieran presidir el empleo del discurso bioético en cualquier punto del complejo social “investigación médica”: miembros de comités de ética de investigación, investigadores, empresarios, administradores. Cada uno de estos grupos, en su “cultura epistémica” propia, define y explicita los principios básicos en tanto expresión de valores y leyes generales. PMID:23459767

Weathering resistance of thin plasma polymer films on pre-coated steel =

NASA Astrophysics Data System (ADS)

Serra, Ricardo Gil Henriques

O trabalho apresentado teve origem no projecto de investigacao “Tailored Thin Plasma Polymers Films for Surface Engineering of Coil Coated Steel”, financiado pelo Programa Europeu ECSC Steel Research. Sistemas de aco galvanizado pre-pintado em banda a base de poliester e poliuretano foram submetidos a um processo de polimerizacao por plasma onde um filme fino foi depositado de modo a modificar as propriedades de superficie. Foram usados reactores de catodo oco, microondas e radio frequencia para a deposicao do polimero fino. Os sistemas preparados foram analisados de modo a verificar a influencia do processo de polimerizacao por plasma na alteracao das propriedades barreira dos sistemas pre-pintados em banda. Foi estudado o efeito dos diferentes passos do processo de polimerizacao por plasma, bem como o efeito de diferentes variaveis operatorias. A mistura precursora foi variada de modo a modificar as propriedades da superficie de modo a poder vir a obter maior hidrofobicidade, maior resistencia a marcas digitais, bem como maior facilidade de limpeza. Os testes foram conduzidos em solucao de NaCl 0,5 M. Para o trabalho foram usadas tecnicas de analise da morfologia da superficie como Microscopia de Forca Atomica e Microscopia Electronica de Varrimento. As propriedades electroquimicas dos sistemas foram estudadas por Espectroscopia de Impedancia Electroquimica. A estrutura dos filmes gerados no processo de polimerizacao por plasma foi caracterizada por Microscopia de Transmissao Electronica. A modificacao das propriedades opticas devido ao processo de polimerizacao por plasma foi tambem obtida.

Improving seasonal forecast through the state of large-scale climate signals

NASA Astrophysics Data System (ADS)

Samale, Chiara; Zimmerman, Brian; Giuliani, Matteo; Castelletti, Andrea; Block, Paul

2017-04-01

Increasingly uncertain hydrologic regimes are challenging water systems management worldwide, emphasizing the need of accurate medium- to long-term predictions to timely prompt anticipatory operations. In fact, forecasts are usually skillful over short lead time (from hours to days), but predictability tends to decrease on longer lead times. The forecast lead time might be extended by using climate teleconnection, such as El Nino Southern Oscillation (ENSO). Despite the ENSO teleconnection is well defined in some locations such as Western USA and Australia, there is no consensus on how it can be detected and used in other river basins, particularly in Europe, Africa, and Asia. In this work, we propose the use of the Nino Index Phase Analysis for capturing the state of multiple large-scale climate signals (i.e., ENSO, North Atlantic Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, Dipole Mode Index). This climate state information is used for distinguishing the different phases of the climate signals and for identifying relevant teleconnections between the observations of Sea Surface Temperature (SST) that mostly influence the local hydrologic conditions. The framework is applied to the Lake Como system, a regulated lake in northern Italy which is mainly operated for flood control and irrigation supply. Preliminary results show high correlations between SST and three to six months ahead precipitation in the Lake Como basin. This forecast represents a valuable information to partially anticipate the summer water availability, ultimately supporting the improvement of the Lake Como operations.

Thermophysical properties of undercooled liquid Co-Mo alloys

NASA Astrophysics Data System (ADS)

Han, X. J.; Wei, B.

2003-05-01

Using electromagnetic levitation in combination with the oscillating drop technique and drop calorimeter method, the surface tensions and specific heats of undercooled liquid Co-10 wt% Mo, Co-26.3 wt% Mo, and Co-37.6 wt% Mo alloys were measured. The containerless state during levitation produces substantial undercoolings up to 223 K (0.13TL), 213 K (0.13TL) and 110 K (0.07TL) respectively for these three alloys. In their respective undercooling ranges, the surface tensions were determined to be 1895 m 0.31(T m 1744), 1932 m 0.33(T m 1682), and 1989 m 0.34(T m 1607) mN mу. According to the Butler equation, the surface tensions of these three Co-Mo alloys were also calculated, and the results agree well with the experimental data. The specific heats of these three alloys are determined to be 41.85, 43.75 and 44.92 J molу Kу. Based on the determined surface tensions and specific heats, the changes in thermodynamics functions such as enthalpy, entropy and Gibbs free energy are predicted. Furthermore, the crystal nucleation, dendrite growth and Marangoni convection of undercooled Co-Mo alloys are investigated in the light of these measured thermophysical properties.