6,101 research outputs found
The role of prefrontal cortex and basal ganglia in model-based and model-free reinforcement learning
Contemporary reinforcement learning (RL) theory suggests that choices can be evaluated either by the model-free (MF) strategy of learning their past worth or the model-based (MB) strategy of predicting their likely consequences based on learning how decision states eventually transition to outcomes. Statistical and computational considerations argue that these strategies should ideally be combined. This thesis aimed to investigate the neural implementation of these two RL strategies and the mechanisms of their interactions. Two non-human primates performed a two-stage decision task designed to elicit and discriminate the use of both MF and MB-RL, while single-neuron activity was recorded from the prefrontal cortex (frontal pole, FP; anterior cingulate cortex, ACC; dorsolateral prefrontal cortex) and striatum (caudate and putamen). Logistic regression analysis revealed that the structure of the task (of MB importance) and the reward history (of MF and MB importance) significantly influenced choice. A trial-by-trial computational analysis also confirmed that choices were made according to a weighted combination of MF and MB- RL, with the influence of the latter approaching 90%. Furthermore, the valuations of both learning methods also influenced response vigour and pupil response. Neural correlates of key elements for MF and MB learning were observed across all brain areas, but functional segregation was also in evidence. Neurons in ACC encoded features of both MF and MB, suggesting a possible role in the arbitration between both strategies. Striatal activity was consistent with a role in value updating by encoding reward prediction errors. Finally, novel neurophysiological evidence was found in favour of the role of the FP in counterfactual processing. In conclusion, this thesis provides insight into the neural implementation of MF and MB-RL computations and their various effects on diverse aspects of behaviour. It supports the parallel operation and integration of the two approaches, while revealing unexpected intricacies
Successful management of bilateral orbital metastases from invasive lobular breast cancer with abemaciclib and letrozole: a case report and literature review
Breast cancer is a significant global health concern, contributing to substantial
morbidity and mortality among women. Hormone receptor-positive (HR+)/HER2-
negative (HER2-) breast cancer constitutes a considerable proportion of cases, and
significant advancements have been made in its management. CDK4/6 inhibitors
(CDK4/6is) are a new targeted therapy that has demonstrated efficacy in adjuvant,
advanced and metastatic settings. The propensity of lobular breast carcinomas for
estrogen-rich sites, such as periocular tissues and orbital fat, may explain their
tendency for orbital metastases. Current treatment strategies for these cases are
predominantly palliative, and the prognosis remains poor. This article presents a
unique case of a 51-year-old female with progressive right periorbital edema, pain,
and limited ocular motility. An imaging work-up showed bilateral intra and
extraconal orbital infiltration, which was biopsied. The histopathologic analysis
disclosed mild chronic inflammatory infiltrate with thickened fibrous tissue and
moderately differentiated lobular carcinoma cells, positive for GATA3 and CK7
markers, with 100% of tumor nuclei expressing estrogen receptors (ER+). A
systemic evaluation showed a multicentric nodular formation in both breasts.
Further diagnostic assessments unveiled an HR+/HER2- bilateral lobular breast
carcinoma with synchronous bilateral orbital metastases. Systemic treatment was
initiated with abemaciclib 150mg twice daily and letrozole 2.5mg once a day.
However, this regimen was interrupted due to toxicity. After two weeks, treatment
was resumed with a reduced abemaciclib dose (100mg twice daily) alongside
letrozole, with a reasonable tolerance. Nearly two years after the initial diagnosis of
inoperable metastatic cancer, the patient remains on the same systemic treatment
regimen with no signs of invasive disease. This case report is the first of a patientpresenting with bilateral orbital metastases from bilateral lobular breast cancer,
showing an impressive and sustained response to a first-line treatment regimen
combining abemaciclib and letrozole. A literature review on bilateral orbital
metastases from breast cancer is also presented.info:eu-repo/semantics/publishedVersio
Socio-professional profile of the foreign teacher in Brazilian public university
Este trabajo, fruto de una tesis de doctorado en educación, tuvo como objetivo comprender la figura del profesor extranjero, su perfil, dificultades, retos y contribución a la permanencia en la reconstrucción de las prácticas didáctico-pedagógicas y su actuación como profesional docente en las universidades públicas brasileñas. El estudio se justifica debido a su número creciente, particularmente durante en los últimos diez años y que, por lo tanto, no ha sido objeto de investigación sistemática. Nuestro universo de investigación ha sido la UNB, Universidad pública federal de Brasilia, que concentra el mayor número de estos profesores. Utilizamos los datos del INEP (microdatos del censo de la educación superior, 2011) como base para localizar a estos docentes. Se aplicaron cuestionarios a más de 37,3% de las nacionalidades presentes (19 de 51 nacionalidades) que corresponde al 7,6% de una población estimada de 250 docentes, como documentos de consulta (sitios web de la escuela, sitio web personal, servicios de fotocopia). El análisis cualitativo y el tratamiento estadístico de los datos nos permitió obtener los siguientes Resultados: los profesores extranjeros que se encuentran en UNB son originarios, en su mayoría, de los países de América Latina y de Europa, son blancos o de color, son doctores y están contratados a tiempo completo y dedicación exclusiva. También intervienen en tareas de investigación y extensión. Estos docentes encuentran grandes dificultades de adaptación a sus lugares de trabajo debido a la falta de mecanismos de socialización y de ayuda en sus prácticas pedagógicas. A la luz de la complejidad del paradigma de Edgar Morin, se puede afirmar que el profesor extranjero sobrevive en la Universidad Pública Brasileña en medio de dilemas y contradicciones tales como problemas culturales, de alteridad y de aceptación por parte de los estudiantes, su inserción en la propia universidad es la busca permanente de medios para poder conectar. Sin embargo, debemos destacar la gran contribución de estos profesores a la calidad de los programas de grado y la inserción internacional de las universidades.This paper fruit of a doctorate thesis in education aimed to understand the foreign teacher, its profile, difficulties, contributions permanence challenges and reconstruction of didactic-pedagogical practices and for its professional exercise in the brazilian public universities. The study was justified because of their increasing number particularly during the last decade and also the lack of systematic research of the thematic. Our universe was the UnB, federal public university of Brasilia where we found the bigger number of these teachers. Using the INEP data (micro data of census of higher education, 2011) we could localize those ones. Questionnaires were applied to more than 37,3% of the nationalities present (19 of 51 nationalities) corresponding to 7,6% of the population estimated to 250 teachers, documents consulting (school websites, personnel website, photocopy services). The qualitative analysis and the statistical data treatment allowed us to obtain the following results: the teachers met at UnB are from Latin America and Europe, are white or brunet, are doctors and are contracted full time. They also act in teaching, research and extension. These teachers met many adaptation difficulties in their workplace due to a lack of socialization and help mechanisms in their teaching practices. By means of the complexity paradigm of Edgar Morin, we could confirm that the foreign teacher survive in the Brazilian public university within dilemmas and contradictions like cultural problems, alterity and acceptation by the students, its insertion in the own university and is always in search for means to connect the parts. Although, we could note the big contributions of these teachers in the quality of the graduate programs and the international insertion of their universities.Esse trabalho, fruto de uma tese de doutorado em educação buscou apreender o professor estrangeiro, no seu perfil, suas dificuldades, suas contribuições e desafios para a permanência e reconstrução das práticas didático-pedagógicas e para a atuação como profissional docente nas universidades públicas brasileiras. O estudo se justificou pelo fato de termos um grande número desses sujeitos nas universidades públicas brasileiras principalmente nos últimos dez anos e que, portanto, nunca foi ainda objeto de um estudo sistemático. Nosso universo de pesquisa foi a UnB, instituição pública federal que concentra o maior número desses professores. Dados do INEP (microdados do censo do ensino superior do ano de 2011) nos serviram de base para localizar esses docentes. Foram aplicados questionários a mais de 37,3% das nacionalidades presentes (19 das 51 nacionalidades) correspondendo a 7,6% de uma população de 250 professores além de entrevistas semiestruturadas, consulta a documentos disponibilizados nas IES e em outros locais (sites web das faculdades, sites pessoais e copiadoras). A análise qualitativa e o tratamento estatístico dos dados nos permitiram chegar as seguintes conclusões: os professores estrangeiros que se encontram na UNB são originários na sua maioria dos países da América Latina e da Europa, se declaram brancos ou pardos, têm títulos de doutores, trabalham em regime de dedicação exclusiva e atuam no ensino, pesquisa e extensão. Esses docentes encontram grandes dificuldades de adaptação em seus locais de trabalho devido à falta de mecanismos de socialização e de auxílio em suas práticas pedagógicas. À luz do paradigma da complexidade de Edgar Morin, pôde se afirmar que o professor estrangeiro sobrevive na universidade pública brasileira em meio a dilemas e contradições que vão desde inquietações culturais, alteridade e aceitação pelos alunos até sua própria integração na universidade e a busca permanente da união dessas partes. No entanto, há de se notar a grande contribuição desses professores no que tange à inserção dos programas de pós-graduação onde atua em altos patamares de qualidade além da além da inserção internacional.peerReviewe
Consciência Política e Corrupção em Moçambique: entre a subalternidade e a transformação
Este artigo discute a importância da Visita Domiciliar, os efeitos O presente artigo aborda a corrupção em Moçambique a partir do olhar de pessoas que nem estudam e nem têm papel de destaque na sociedade moçambicana. Para essa análise utilizou-se do referencial psicopolítico da consciência política e observou-se como a questão da etnicidade e da sobrevivência ganham força a hora de entender a vida cotidiana em uma sociedade pluriétnica e marcada pelos traumas de uma guerra civil. Subalternidade e transformação se revelam como elementos espaço-temporais da cotidianidade moçambicana
Optimal locations of groundwater extractions in coastal aquifers
A regional water supply management model for coastal aquifers was developed.
One of its outcomes is the definition of the optimized locations for groundwater
withdrawal. Such a tool permits the analysis of alternative plans for groundwater extraction
and the sustainable use of water resources in a coastal aquifer subject to saltwater intrusion.
The principal components are the evolutionary optimization and the analytical/numerical
simulation models. The optimization technique looks for the best well locations taking into
consideration the economic results and the satisfaction of the societal water demand.
However these two concerns are conditioned by trying to control the saltwater intrusion,
i.e., preserving the environmental equilibrium. The simulation model uses the governing
mathematical equations for groundwater movement to find the interface between freshwater
and saltwater. Because of the non-linearity in the system and the possibility of a jumping
interface, a security distance was defined. This is a controlling variable which can be set by
the decision makers. The model was applied to a typical case with interesting results. For
example, diagrams showing the relationship between the location of the wells and the
security distance(s) are of importance to the managers. It was also crucial to have an
understanding of the tradeoffs between groundwater withdrawals, positions of the wells
from the coast line, and the security distance. The model was also applied to a real case in
order to relate the extractions, distances and artificial recharge (not presented in this paper).Civil Engineering Research Centre of the University of Minho.Science and Technology Foundation -POCTI/ECM/2512/9
Los conocimientos profesionales en la atención primaria de la salud de la persona/familia en la angustia mental: perspectiva Le Boterf
O objetivo deste trabalho foi identificar os saberes e fazeres constituídos na prática da Saúde da Família (SF), na visão dos enfermeiros, no que se refere ao atendimento à pessoa e família em sofrimento mental na perspectiva dos saberes profissionais de Le Boterf. Método: Foi feito uma pesquisa descritiva exploratória de abordagem qualitativa, delineada para apresentar e aprofundar a construção de competências dos profissionais enfermeiros, foi aplicada em 3 Unidades da SF. Resultados: fazendo uma análise temática, chegou-se às seguintes categorias: “Saber agir com pertinência”; “Saber mobilizar saberes e conhecimentos em um contexto profissional”; “Saber interagir saberes múltiplos”; “Saber transpor”; “Saber aprender e saber aprender a aprender”; “Saber envolver-se”. Considerações finais: verificou-se que entre os saberes a maior dificuldade é a de “saber transpor”, e que o cotidiano das equipes de SF exige muito desse saber. Foi verificado pouca transposição de saberes/fazeres em situações reais.El objetivo del estudio fue identificar los conocimientos y acciones en la práctica de la Salud de la Familia (SF), a la vista de las enfermeras en relación con la persona y la familia en el cuidado angustia mental en términos de conocimientos profesionales de Le Boterf. Método: Un estudio cualitativo exploratorio descriptivo, se indica para introducir y profundizar en el desarrollo de habilidades de las enfermeras, aplicado a 3 unidades SF. Resultados: hacer un análisis temático, llegó a las siguientes categorías: “Saber actuar correctamente”; “Conociendo a movilizar conocimientos y experiencia en el ámbito profesional”; “Sabiendo que interactúan múltiples saberes”; “Sabiendo transponer”; “El saber aprender y saber cómo aprender a aprender”; “Sabiendo participar”. Consideraciones finales: se encontró el conocimiento de la mayor dificultad es la de "ser capaz de incorporar", y que los equipos diarias SF requiere mucho este conocimiento. Poco transposición del saber/hacer en situaciones reales ha sido verificada.Aim of this study was to identify knowing-doing actions constituted the practice of Family Health (FH), in view of nurses in relation to the person and family care in mental distress in terms of professional knowledge of Le Boterf. Method: Descriptive exploratory qualitative study, to deepen contruction of nurse in FH. The survey was conducted in 3 Units FH. Result: Doing a thematic analysis, came to the following categories: “Knowing how to act and react with relevance”; “Knowing how to combine resources and mobilize them in a professional context”; “Knowing how to interact with multiple knowledges”; “Knowing how to transpose”; “Knowing how to learn and knowing how to learn to learn”; “Knowing how to engage”. Final considerations: the greatest difficulty was "be able to transpose," and that the daily demand of the FH teams requires a lot of this knowledge. Little transposition of knowing-doing in real situations has been verified
Validação conceitual das características definidoras de diagnósticos de enfermagem respiratórios em neonatos
OBJECTIVE:To develop and validate conceptual and operational definitions for the defining characteristics of the respiratory nursing diagnoses, ineffective breathing pattern, impaired gas exchange and impaired spontaneous ventilation, in newborns.METHODS:This was a methodological study of conceptual validation of the defining characteristics of three respiratory nursing diagnoses, by consensus analysis of a committee of five specialist nurses, and then a group of five non-nursing professionals, using the Delphi technique.RESULTS:After two rounds of evaluation, consensus was obtained that was equal to or greater than 80% on all of the definitions, which were then considered validated.CONCLUSION:The definitions developed for the defining characteristics of three nursing diagnoses were validated with a high level of consensus.OBJETIVO:Elaborar e validar definições conceituais e operacionais para as características definidoras dos diagnósticos de enfermagem respiratórios, Padrão Respiratório Ineficaz, Troca de Gases Prejudicada e Ventilação Espontânea Prejudicada em recém-nascidos.MÉTODOS:Estudo metodológico, de validação conceitual das características definidoras dos três diagnósticos de enfermagem respiratórios por meio da análise de consenso de um comitê de cinco enfermeiras especialistas e de cinco profissionais não enfermeiros, utilizando a técnica Delphi.RESULTADOS:Após duas rodadas de avaliação, obteve-se consenso igual ou superior a 80% na totalidade das definições, sendo consideradas validadas.CONCLUSÃO:As definições elaboradas para as características definidoras dos três diagnósticos de enfermagem foram validadas com elevado grau de consenso.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de EnfermagemUNIFESP, EPESciEL
Osteoblast-Restricted Disruption of the Growth Hormone Receptor in Mice Results in Sexually Dimorphic Skeletal Phenotypes
Growth hormone (GH) exerts profound anabolic actions during postnatal skeletal development, in part, through stimulating the production of insulin-like growth factor-1 (IGF-1) in liver and skeletal tissues. To examine the requirement for the GH receptor (GHR) in osteoblast function in bone, we used Cre-LoxP methods to disrupt the GHR from osteoblasts, both in vitro and in vivo. Disruption of GHR from primary calvarial osteoblasts in vitro abolished GH-induced signaling, as assessed by JAK2/STAT5 phosphorylation, and abrogated GH-induced proliferative and anti-apoptotic actions. Osteoblasts lacking GHR exhibited reduced IGF-1-induced Erk and Akt phosphorylation and attenuated IGF-1-induced proliferation and anti-apoptotic action. In addition, differentiation was modestly impaired in osteoblasts lacking GHR, as demonstrated by reduced alkaline phosphatase staining and calcium deposition. In order to determine the requirement for the GHR in bone in vivo, we generated mice lacking the GHR specifically in osteoblasts (ΔGHR), which were born at the expected Mendelian frequency, had a normal life span and were of normal size. Three week-old, female ΔGHR mice had significantly reduced osteoblast numbers, consistent with the in vitro data. By six weeks of age however, female ΔGHR mice demonstrated a marked increase in osteoblasts, although mineralization was impaired; a phenotype similar to that observed previously in mice lacking IGF-1R specifically in osteoblasts. The most striking phenotype occurred in male mice however, where disruption of the GHR from osteoblasts resulted in a feminization of bone geometry in 16 week-old mice, as observed by μCT. These results demonstrate that the GHR is required for normal postnatal bone development in both sexes. GH appears to serve a primary function in modulating local IGF-1 action. However, the changes in bone geometry observed in male ΔGHR mice suggest that, in addition to facilitating IGF-1 action, GH may function to a greater extent than previously appreciated in establishing the sexual dimorphism of the skeleton
Preliminary Limits on the WIMP-Nucleon Cross Section from the Cryogenic Dark Matter Search (CDMS)
We are conducting an experiment to search for WIMPs, or weakly-interacting
massive particles, in the galactic halo using terrestrial detectors. This
generic class of hypothetical particles, whose properties are similar to those
predicted by extensions of the standard model of particle physics, could
comprise the cold component of non-baryonic dark matter. We describe our
experiment, which is based on cooled germanium and silicon detectors in a
shielded low-background cryostat. The detectors achieve a high degree of
background rejection through the simultaneous measurement of the energy in
phonons and ionization. Using exposures on the order of one kilogram-day from
initial runs of our experiment, we have achieved (preliminary) upper limits on
the WIMP-nucleon cross section that are comparable to much longer runs of other
experiments.Comment: 5 LaTex pages, 5 eps figs, epsf.sty, espcrc2dsa2.sty. Proceedings of
TAUP97, Gran Sasso, Italy, 7-11 Sep 1997, Nucl. Phys. Suppl., A. Bottino, A.
di Credico and P. Monacelli (eds.). See also http://cfpa.berkeley.ed
Performance of single wire earth return transformers with amorphous alloy core in a rural electric energy distribution system
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