Feynman parametrization and Mellin summation at finite temperature

We show that the Mellin summation technique (MST) is a well defined and useful tool to compute loop integrals at finite temperature in the imaginary-time formulation of thermal field theory, especially when interested in the infrared limit of such integrals. The method makes use of the Feynman parametrization which has been claimed to have problems when the analytical continuation from discrete to arbitrary complex values of the Matsubara frequency is performed. We show that without the use of the MST, such problems are not intrinsic to the Feynman parametrization but instead, they arise as a result of (a) not implementing the periodicity brought about by the possible values taken by the discrete Matsubara frequencies before the analytical continuation is made and (b) to the changing of the original domain of the Feynman parameter integration, which seemingly simplifies the expression but in practice introduces a spurious endpoint singularity. Using the MST, there are no problems related to the implementation of the periodicity but instead, care has to be taken when the sum of denominators of the original amplitude vanishes. We apply the method to the computation of loop integrals appearing when the effects of external weak magnetic fields on the propagation of scalar particles is considered.Comment: 16 pages, 1 figure. Discussion expanded. References added. Published versio

Examination of the Relationship between In-Store Environmental Factors and Fruit and Vegetable Purchasing among Hispanics.

Retail food environments have received attention for their influence on dietary behaviors and for their nutrition intervention potential. To improve diet-related behaviors, such as fruit and vegetable (FV) purchasing, it is important to examine its relationship with in-store environmental characteristics. This study used baseline data from the "El Valor de Nuestra Salud" study to examine how in-store environmental characteristics, such as product availability, placement and promotion, were associated with FV purchasing among Hispanic customers in San Diego County. Mixed linear regression models indicated that greater availability of fresh FVs was associated with a $0.36 increase in FV purchasing (p = 0.01). Placement variables, specifically each additional square foot of display space dedicated to FVs (p = 0.01) and each additional fresh FV display (p = 0.01), were associated with a$0.02 increase and $0.29 decrease, respectively, in FV purchasing. Introducing FV promotions in the final model was not related to FV purchasing. Exploratory analyses indicated that men reported spending$3.69 fewer dollars on FVs compared to women, controlling for covariates (p = 0.02). These results can help inform interventions targeting in-store environmental characteristics to encourage FV purchasing among Hispanics

Predictors of Routine Medical Care Use among Mexican Immigrants/Mexican-Americans Varying in Legal Status

Background: Immigration has been the focus of intense political debate, with a recurrent theme being the use of public services, including healthcare. Although Latinos are the largest and fastest growing ethnic group in the United States (U.S.), evidence suggests they underutilize healthcare, with Mexican Immigrants and Mexican Americans (MI-MA) living on the U.S.-Mexico border exhibiting the greatest disparities. Objective: This study explored the association of predisposing, enabling and need characteristics, including legal status, with the use of routine medical care (RMC) among 387 MI-MA living on the California-Mexico border. Methods: This cross-sectional study used data collected in 2009 for the San Diego Prevention Research Center (SDPRC) community survey; data analyses were completed in Summer 2012. This study involved multistage sampling and recruitment of Latino adults in 200 census blocks near the California-Mexico border to complete an interview and height and weight measurements. Sequential logistic regressions assessed the relative contribution of predisposing, enabling and need factors to the use of RMC. Results: Predisposing and enabling factors (gender, undocumented status, cost) distinguished between respondents with recent (<1 year) versus limited (≥ 5 years including never) use of RMC, whereas enabling and need factors (insurance, dispositional trust, presence of a chronic illness) adequately differentiated between those with recent versus delayed (≥1 year, but <5 years) use. Undocumented status distinguished between those with delayed versus limited use of RMC. Conclusions: Consideration of different factors, including financial difficulties and legal status, is necessary for promoting use of RMC among MI-MA living in this border region.Contexte : L'immigration est au cœur de débats politiques intenses, dont l'un des thèmes récurrents est l'utilisation des services publics, et notamment des soins de santé. Bien que les Latinos constituent le groupe ethnique le plus important et connaissant la croissance la plus rapide des Etats-Unis, les données semblent indiquer qu'ils sous-utilisent les services de santé, les immigrés mexicains et les Américano-Mexicains (IM-AM) vivant à la frontière américano-mexicaine affichant les plus fortes disparités. Objectif : Cette étude a exploré les liens entre les facteurs prédisposants, favorables et de nécessité, dont le statut juridique, et l'utilisation des soins médicaux courants (SMC) chez 387 IM-AM vivant à la frontière entre la Californie et le Mexique. Méthodes : Cette étude transversale s'est fondée sur les données recueillies en 2009 dans le cadre de l'enquête communautaire du San Diego Prevention Research Center (SDPRC), dont l'analyse s'est achevée à l'été 2012. Cette étude prévoyait un échantillonnage à plusieurs degrés et le recrutement d'adultes latinos dans 200 îlots de recensement situés à proximité de la frontière entre la Californie et le Mexique, afin de les interroger et de relever des mesures de taille et de poids. Des modèles de régression logistique séquentielle ont permis d’évaluer la contribution relative des facteurs prédisposants, favorables et de nécessité à l'utilisation des SMC.  Résultats : Les facteurs prédisposants et favorables (sexe, statut non documenté, coût) faisaient la différence entre les répondants ayant récemment (<1 an) ou peu (≥ 5 ans ou jamais) eu recours aux SMC, tandis que les facteurs favorables et de nécessité (assurance, prédisposition à faire confiance, présence de maladie chronique) distinguaient convenablement ceux qui avaient récemment eu recours aux SMC de ceux qui y avaient eu recours tardivement (≥1 an, mais <5 ans). Le statut non documenté faisait la différence entre ceux qui avaient tardivement ou peu eu recours aux SMC. Conclusions : La prise en compte des différents facteurs, y compris des difficultés financières et du statut légal, est nécessaire pour encourager l'utilisation des SMC chez les IM-AM vivant dans cette région frontalière.Antecedentes: La inmigración es objeto de un intenso debate político en el que uno de los temas recurrentes es el uso de los servicios públicos, entre ellos la atención sanitaria. Aunque los latinos constituyen el grupo étnico más numeroso y de más rápido crecimiento en Estados Unidos, las pruebas indican que no utilizan lo suficiente las instituciones de asistencia sanitaria. Son los inmigrantes mexicanos y los estadounidenses de origen mexicano que viven en la frontera entre Estados Unidos y México los que mayores disparidades muestran al respecto.  Objetivo: Este estudio analizó la asociación existente entre las características de los predisponentes, facilitadores y factores de necesidad, como el estado legal, y el uso de la asistencia médica rutinaria entre 387 estadounidenses de origen mexicano residentes en la frontera de California con México. Métodos: Este estudio transversal utilizó los datos recopilados en 2009 para un estudio comunitario del Centro de Investigación para la Prevención en San Diego (SDPRC), y el análisis de los datos se llevó a cabo en verano de 2012. Se realizaron muestreos en diferentes fases y se reclutaron adultos latinos en bloques censales de 200 cerca de la frontera mexicana con California para completar una entrevista y realizar mediciones de peso y altura. Las regresiones logísticas secuenciales evaluaron la contribución relativa de los predisponentes, facilitadotes y factores de necesidad al uso de la atención médica rutinaria.  Resultados: Los predisponentes y facilitadores (género, situación ilegal o “sin papeles”, coste) variaron entre los participantes entre un uso reciente (<1 año) o limitado (≥ 5 años, o nunca) de la atención médica rutinaria, mientras que los facilitadotes y factores de necesidad (seguro, confianza, presencia de enfermedad crónica) se diferenciaron de forma adecuada entre un uso reciente o retardado (≥1 año, pero <5 años). El estado de indocumentado se diferenció igualmente entre un uso retardado o limitado de la asistencia médica rutinaria. Conclusiones: Es necesario tener en cuenta factores diversos, como las dificultades económicas y la situación jurídica, para promover el uso de la asistencia médica rutinaria entre los estadounidenses de origen mexicano que residen en esta región fronteriza

Role of 5 α -dihydrotestosterone in testicular development of gilthead seabream following finasteride administration

In teleosts, spermatogenesis is regulated by pituitary gonadotropins and sex steroids. 5α-dihydrotestosterone (DHT), derived from testosterone (T) through the action of 5α-reductase, has recently been suggested to play a physiologically important role in some fish species. In this study, gilthead seabream, Sparus aurata L., males received an implant of 1μg T/g body mass (bm) or vehicle alone and, 7 days later, 1 mg finasteride (FIN, an inhibitor of 5α-reductase)/kg bm or vehicle. Serum levels of T, 11-ketotestosterone (11KT), DHT and 17β-estradiol (E2), and the mRNA levels of the main enzymes involved in their synthesis, were analysed. T promoted a transient increase in the serum levels of T, 11KT and E2 but a decrease in those of DHT at day 15 following T injection, in accordance with the up-regulation of mRNA levels of the enzymes involved in T transformation to 11KT (coding genes: cyp11b1 and hsd11b) and the down-regulation of mRNA levels of the enzyme responsible for T transformation to DHT (coding gene:srd5a). Interestingly, a similar effect was observed when FIN was in- jected. However, when fish were injected with T and FIN successively (T + FIN), control levels were not re-covered at the end of the experimental period (28 days). DHT seems to regulate E2 serum levels via the down-regulation of mRNA levels of aromatase (coding gene:cyp19a1a), which is needed for the transformation of T into E2. The testis histology, together with the proliferative rates recorded upon T, FIN or T + FIN treatment, suggests that DHT is involved in the onset of the meiotic phase of spermatogenesis.Versión del edito

A beam-beam monitoring detector for the MPD experiment at NICA

The Multi-Purpose Detector (MPD) is to be installed at the Nuclotron Ion Collider fAcility (NICA) of the Joint Institute for Nuclear Research (JINR). Its main goal is to study the phase diagram of the strongly interacting matter produced in heavy-ion collisions. These studies, while providing insight into the physics of heavy-ion collisions, are relevant for improving our understanding of the evolution of the early Universe and the formation of neutron stars. In order to extend the MPD trigger capabilities, we propose to include a high granularity beam-beam monitoring detector (BE-BE) to provide a level-0 trigger signal with an expected time resolution of 30 ps. This new detector will improve the determination of the reaction plane by the MPD experiment, a key measurement for flow studies that provides physics insight into the early stages of the reaction. In this work, we use simulated Au+Au collisions at NICA energies to show the potential of such a detector to determine the event plane resolution, providing further redundancy to the detectors originally considered for this purpose namely, the Fast Forward Detector (FFD) and the Hadron Calorimeter (HCAL). We also show our results for the time resolution studies of two prototype cells carried out at the T10 beam line at the CERN PS complex.Comment: 16 pages, 12 figures. Updated to published version with added comments and correction

Cobertura vacunal sarampión-rubéola en aspirantes al ingreso en el Instituto de Formación Superior IFSP 6001, La Plata año 2014

El sarampión (S) y la rubéola (R) son enfermedades inmunoprevenibles de reservorio humano exclusivo, pasibles de eliminación/erradicación. La vacunación para S se inició en nuestro país en el año 1971 a los 9 meses de edad; y, fue utilizada con diferentes esquemas. Objetivos: Identificar las coberturas de vacunación e implementar la vacunación con indicación personalizada para iniciar/completar esquemas.Facultad de Ciencias Médica

Cobertura vacunal sarampión-rubéola en aspirantes al ingreso en el Instituto de Formación Superior IFSP 6001, La Plata año 2014

El sarampión (S) y la rubéola (R) son enfermedades inmunoprevenibles de reservorio humano exclusivo, pasibles de eliminación/erradicación. La vacunación para S se inició en nuestro país en el año 1971 a los 9 meses de edad; y, fue utilizada con diferentes esquemas. Objetivos: Identificar las coberturas de vacunación e implementar la vacunación con indicación personalizada para iniciar/completar esquemas.Facultad de Ciencias Médica