Upper Bound on the Hadronic Light-by-Light Contribution to the Muon g-2

There are indications that hadronic loops in some electroweak observables are almost saturated by parton level effects. Taking this as the hypothesis for this work, we propose a genuine parton level estimate of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon, a_mu (LBL,had). Our quark mass definitions and values are motivated in detail, and the simplicity of our approach allows for a transparent error estimate. For infinitely heavy quarks our treatment is exact, while for asymptotically small quark masses a_mu (LBL,had) is overestimated. Interpolating, this suggests quoting an upper bound. We obtain a_mu (LBL,had) < 1.59 10^-9 (95% CL).Comment: 4 pages; 2 references added, some changes in text; final versio

Microglia clearance of single dying oligodendrocytes is mediated by Cx3cr1

Myelin sheath, generated by oligodendrocytes, plays a vital role in ensheathing axons for efficient neural communication. Degeneration of myelin sheath is associated with several neurodegenerative diseases and aging. When myelin sheaths are damaged or degenerated, the resulting debris needs to be efficiently cleared to allow for regeneration and remyelination. The causes of myelin degeneration in various diseases vary, but the inability to effectively remove the myelin debris contributes to disease development and prevents tissue healing. Microglia are highly specialized phagocytic cells capable of recognizing and engulfing myelin debris. The Cx3cr1 gene, which is primarily expressed on microglial cells, plays a significant role in the process of debris clearance. To investigate the role of Cx3cr1 on clearance of single dying oligodendrocytes, we used a technique called 2Phatal. Longitudinal in vivo imaging revealed that microglia lacking the CX3CR1 receptor took on average 3 days longer to clear the targeted oligodendrocytes compared to controls. This suggests that Cx3cr1 plays a critical role in facilitating the rapid and efficient removal of dying oligodendrocytes.https://digitalcommons.dartmouth.edu/wetterhahn_2023/1000/thumbnail.jp

Aprender en grupo: experiencia de estudiantes de enfermería e implicaciones para la formación profesional

O objetivo desta pesquisa é compreender a experiência dos estudantes dos cursos de bacharelado e licenciatura em Enfermagem da Escola de Enfermagem de Ribeirão Preto/Universidade de São Paulo, no que se refere à aprendizagem em grupo, em disciplinas que possibilitam trabalhar em pequenos grupos de estudantes. Foram realizadas entrevistas não estruturadas com 19 alunos do segundo ano desses cursos, de abril a dezembro de 2007, e a análise qualitativa dos dados, pela qual se configuraram as categorias de codificação: Trabalhar em grupo facilita o aprendizado cognitivo e atitudinal; Trabalhar em grupo revela limites e requer mudanças; Trabalhar em grupo exige preparo e nova competência do professor; e Trabalhar em grupo possibilita um exercício para a prática profissional. A estratégia grupal contribui para o processo ensino-aprendizagem, promovendo mudanças na relação do estudante com o conhecimento, com o professor, com o colega e consigo mesmo.This research aims to understand the experience of students in the Bachelor and Teaching Diploma Nursing programs at the University of São Paulo in Ribeirão Preto College of Nursing (EERP/USP), Brazil, with respect to group learning, in subjects that permit working in small student groups. Non-structured interviews were held with 19 second-year students from the two programs, between April and December 2007. Qualitative data analysis was used, configuring codification categories: group work facilitates cognitive and attitudinal learning; group work reveals limits and demands changes; group work demands preparation and new competence from the teacher; group work permits an exercise for professional practice. Working in small groups makes it possible to exercise the professional practice. The group strategy contributes to the teaching-learning process, promoting changes in the student's relation with the knowledge, teachers, fellow students and themselves.La finalidad de esta investigación es comprehender la experiencia de los estudiantes de los cursos de bachillerato y licenciatura en enfermería, de la Escuela de Enfermería de Ribeirão Preto/Universidad de São Paulo, con relación al aprendizaje en grupo, en asignaturas que posibilitan trabajar en pequeños grupos de estudiantes. Fueron realizadas entrevistas no estructuradas con 19 alumnos del segundo año de estos cursos, de abril a diciembre de 2007. Se llevó a cabo el análisis cualitativo de los datos, siendo configuradas categorías de codificación: trabajar en grupo facilita el aprendizaje cognitivo y actitudinal; trabajar en grupo marca límites y requiere cambios; trabajar en grupo exige preparación y nueva competencias del profesor; trabajar en grupo posibilita un ejercicio para la práctica profesional. La estrategia grupal contribuye al proceso enseñanza-aprendizaje, promoviendo cambios en la relación del estudiante con el conocimiento, con el profesor, con el colega y consigo mismo

Territorial differences in the return to education in Chile: Evidence for the Biobio and Metropolitana regions

This paper addresses the differences in the return to education between two regions with the greatest number of higher-education institutions in Chile, Biobio and Metropolitana. Several variants of the Mincer equation are estimated under the Heckit approach using data from the CASEN survey of 2000 and 2011. The results confirm the existence of territorial differences to the detriment of the Biobio region, which are observed in the returns to education, labor experience, and credential effect. Furthermore, the evidence supports the idea of a strong gender gap in earnings inside both regions and the presence of ethnic discrimination in the Metropolitana region.El presente trabajo aborda las diferencias en el retorno de la educación entre dos de las regiones con mayor presencia de instituciones de educación superior en Chile, Biobío y Metropolitana. Diversas variantes de la ecuación de Mincer son estimadas mediante el método Heckit empleando datos provenientes de la encuesta CASEN de los años 2000 y 2011. Los resultados corroboran la existencia de diferencias territoriales en desmedro del Biobío, las que se observan en el retorno a la educación, a la experiencia y en el efecto título. Finalmente, la evidencia constata la presencia de discriminación laboral por género en ambas regiones y por etnia sólo en la región Metropolitana

Chronic stress influences the immune system through the thyroid axis

The aim of the present work was to analyze the effect of chronic stress on thyroid axis and its influence on the immune response. For this purpose a murine model of chronic stress was developed to evaluate and to correlate thyroid hormone levels with humoral alloimmune response. Results show a reduction in serum levels of thyroid hormones, specially a significant decrease in serum levels of tri-iodotyronine (T3) in stressed animals. On the other hand, alloimmunization was not able to induce an early increment in T3 and thyroxine (T4) levels as it was previously reported in normal animals. In addition, lower titers of alloantibodies were obtained in animals under stress conditions as compared to normal mice. The sustitutive T4 treatment in stressed animals increased significantly alloantibody production as well as the early increment in thyroid hormones after antigenic challenge. These findings suggest that chronic stress induces an alteration of the function of thyroid axis that alters the immune response. (C) 2000 Elsevier Science Inc.Fil: Cremaschi, Graciela Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Gorelik, Gabriela Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Klecha, Alicia Juana. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lysionek, Alexis E.. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Genaro, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentin

Assessment of thunderstorm-induced asthma using Google Trends

status: publishe

An Efficient Dynamic Version of the Distal Spatial Approximation Trees

Metric space indices make searches for similar objects more efficient in various applications, including multimedia databases and other repositories which handle complex and unstructured objects. Although there are a plethora of indexes to speed up similarity searches, the Distal Spatial Approximation Tree (DiSAT) has shown to be very efficient and competitive. Nevertheless, for its construction, we need to know all the database objects beforehand, which is not necessarily possible in many real applications. The main drawback of the DiSAT is that it is a static data structure. That means, once built, it is difficult to insert new elements into it. This restriction rules it out for many exciting applications. In this paper, we overcome this weakness. We propose and study a dynamic version of DiSAT that allows handling lazy insertions and, at the same time, improves its good search performance. Therefore, our proposal provides a good tradeoff between construction cost, search cost, and space requirement. The result is a much more practical data structure that can be useful in a wide range of database applications.XIX Workshop Base de Datos y Minería de Datos (WBDMD)Red de Universidades con Carreras en Informátic