Constraints to the magnetospheric properties of T Tauri stars. I. The C II], Fe II] and Si II] ultraviolet features

The C II] feature at ~2325 Angstrom is very prominent in the spectra of T Tauri stars (TTSs). This feature is a quintuplet of semiforbidden transitions excited at electron temperatures around 10,000 K that, together with the nearby Si II] and Fe II] features, provides a reliable optically thin tracer for accurate measurement of the plasma properties in the magnetospheres of TTSs. The spectra of 20 (out of 27) TTSs observed with the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST) have good enough signal to noise ratio (S/N) at the C II] wavelength. For these stars we have determined electron densities (ne) and temperatures (Te) in the line emission region as well as the profile broadening (sigma). For most of the stars in the sample (17) we obtain 10^{4.1} < Te < 10^{4.5} K and 10^{8} < ne < 10^{12} cm^{-3}. These stars have suprathermal line broadening (35 < sigma < 165 km s^{-1}), except TW Hya and CY Tau with thermal line broadening. Both C II] line luminosity and broadening are found to correlate with the accretion rate. Line emission seems to be produced in the magnetospheric accretion flow, close to the disk. There are three exceptions: DG Tau, RY Tau and FU Ori. The line centroids are blueshifted indicating that the line emission in these three stars is dominated by the outflow.Comment: 13 pages, 15 figures, published in MNRAS minor change

Constraints to the magnetospheric properties of T Tauri stars - II. The Mg II ultraviolet feature

The atmospheric structure of T Tauri Stars (TTSs) and its connection with the large scale outflow is poorly known. Neither the effect of the magnetically mediated inter- action between the star and the disc in the stellar atmosphere is well understood. The Mg II multiplet is a fundamental tracer of TTSs atmospheres and outflows, and is the strongest feature in the near-ultraviolet spectrum of TTSs. The International Ultraviolet Explorer and Hubble Space Telescope data archives provide a unique set to study the main physical compounds contributing to the line profile and to derive the properties of the line formation region. The Mg II profiles of 44 TTSs with resolution 13,000 to 30,000 are available in these archives. In this work, we use this data set to measure the main observables: flux, broadening, asymmetry, terminal velocity of the outflow, and the velocity of the Discrete Absorption Components. For some few sources repeated observations are available and variability has been studied. There is a warm wind that at sub-AU scales absorbs the blue wing of the Mg II profiles. The main result found in this work is the correlation between the line broadening, Mg II flux, terminal velocity of the flow and accretion rate. Both outflow and magnetospheric plasma contribute to the Mg II flux. The flux-flux correlation between Mg II and C IV or He II is confirmed; however, no correlation is found between the Mg II flux and the ultraviolet continuum or the H2 emission.Comment: 21 pages, 20 figure

Variation of the ultraviolet extinction law across the Taurus-Auriga star forming complex. A GALEX based study

The Taurus-Auriga molecular complex (TMC) is the main laboratory for the study of low mass star formation. The density and properties of interstellar dust are expected to vary across the TMC. These variations trace important processes such as dust nucleation or the magnetic field coupling with the cloud. In this article, we show how the combination of near ultraviolet (NUV) and infrared (IR) photometry can be used to derive the strength of the 2175 \AA\ bump and thus any enhancement in the abundance of small dust grains and PAHs in the dust grains size distribution. This technique is applied to the envelope of the TMC, mapped by the GALEX All Sky Survey (AIS). UV and IR photometric data have been retrieved from the GALEX-AIS and the 2MASS catalogues. NUV and K-band star counts have been used to identify the areas in the cloud envelope where the 2175 \AA\ bump is weaker than in the diffuse ISM namely, the low column density extensions of L1495, L1498 and L1524 in Taurus, L1545, L1548, L1519, L1513 in Auriga and L1482-83 in the California region. This finding agrees with previous results on dust evolution derived from Spitzer data and suggests that dust grains begin to decouple from the environmental galactic magnetic field already in the envelope.Comment: Accepted in Monthly Notices of the Royal Astronomical Societ

Seguridad alimentaria y nutricional en México durante la pandemia por SARS-CoV-2: Revisión sistemática

Introduction: The food security and nutrition of individuals was affected due to the coronavirus (COVID-19) pandemic. Increased food insecurity limits individuals from having a full and dignified quality of life. Objective: To assess the access and availability of food security in the Mexican population affected by the COVID-19 pandemic in Mexico through a literature review. Methods: Literature review in databases such as: PubMed, Science Direct, Scielo, FAO, UN, ENSANUT, Salud Pública de México and CONACYT. The search for information was carried out from November 2021 to May 2022, considering articles published from March 2020 and in relation to the health contingency period. A search equation was used for the search and, in addition, the methodological evaluation of Munns et al., was applied. Articles in Spanish and English were included, with content referring to Mexico. Results: A total of 274 articles were identified in databases; based on the eligibility criteria, surveys and/or articles on nutrition, food security and lifestyle during the pandemic in Mexico were considered. Articles were excluded for having another study design (2), title (100), abstract (82), non-relevant information (54) and (9) for full text, because they did not meet the proposed characteristics. Finally, 10 articles were selected for the literature review. With this, the data showed that the COVID-19 pandemic caused diverse affectations in the Mexican territory, this was evidenced after an increase in food insecurity and changes in lifestyle. Conclusions: Food security and nutrition of individuals were affected in the Mexican population, due to economic issues, changes in dietary patterns, as well as job losses and loss of income.Introducción: La seguridad alimentaria y nutricional de los individuos se vio afectada, debido a la pandemia por el coronavirus (COVID-19). El incremento de la inseguridad alimentaria limita a los individuos a tener una calidad de vida plena y digna. Objetivo: Evaluar el acceso y disponibilidad de la seguridad alimentaria en la población mexicana afectada por la pandemia de COVID-19 en México mediante una revisión de literatura. Metodología: Revisión de literatura en bases de datos como: PubMed, ScienceDirect, Scielo, FAO, ONU, ENSANUT, Salud Pública de México y CONACYT. La búsqueda de información se realizó de noviembre de 2021 a mayo de 2022, se consideraron artículos publicados a partir de marzo de 2020 y en relación con el periodo de contingencia sanitaria. Para la búsqueda se empleó una ecuación de búsqueda y, además, se aplicó la evaluación metodológica de Munns y cols. Fueron incluidos artículos en idioma español e inglés, con contenido referente a México. Resultados: Se identificaron 274 artículos en bases de datos, a partir de los criterios de elegibilidad se contemplaron encuestas y/o artículos sobre nutrición, seguridad alimentaria y estilo vida durante la pandemia en México. Se excluyeron artículos por tener otro diseño de estudio (2), título (100), resumen (82), información no relevante (54) y (9) por texto completo, debido a que no cumplían con las características propuestas. Finalmente se seleccionaron 10 artículos para la revisión de literatura. Con esto, los datos mostraron que la pandemia por COVID-19 provocó diversas afectaciones en el territorio mexicano, esto se evidenció tras un incremento de la inseguridad alimentaria y cambios en el estilo de vida. Conclusiones:  La seguridad alimentaria y nutrición de los individuos se vieron afectados en la población mexicana, debido a cuestiones económicas, cambios en los patrones alimentarios, además de pérdidas de empleo y pérdidas de ingresos

Pleuroparenchymal Fibroelastosis : a New Entity within the Spectrum of Rare Idiopathic Interstitial Pneumonias

Pleuroparenchymal fibroelastosis (PPFE) is a rare entity that has been recently included in the official American Thoracic Society/European Respiratory Society (ATS/ERS) statement in 2013 as a group of rare idiopathic interstitial pneumonias (IIPs). PPFE is characterized by pleural and subpleural parenchymal thickening due to elastic fiber proliferation, mainly in the upper lobes. The etiology of the disease is unclear, although some cases have been associated as a complication after bone marrow transplantation, lung transplantation (LT), chemotherapy, and recurrent respiratory infections. The patients usually report progressive dyspnea and dry cough and are predisposed to develop spontaneous or iatrogenic pneumothoraces after surgical lung biopsy (SLB) for its diagnosis. That is why better awareness with the clinical and radiologic features can help optimal management by the multidisciplinary team. Novel invasive techniques such as cryobiopsy may become useful tools in these patients as it could spare SLB. We present the first reported cases in Spain

Podocalyxin Is a Novel Polysialylated Neural Adhesion Protein with Multiple Roles in Neural Development and Synapse Formation

Neural development and plasticity are regulated by neural adhesion proteins, including the polysialylated form of NCAM (PSA-NCAM). Podocalyxin (PC) is a renal PSA-containing protein that has been reported to function as an anti-adhesin in kidney podocytes. Here we show that PC is widely expressed in neurons during neural development. Neural PC interacts with the ERM protein family, and with NHERF1/2 and RhoA/G. Experiments in vitro and phenotypic analyses of podxl-deficient mice indicate that PC is involved in neurite growth, branching and axonal fasciculation, and that PC loss-offunction reduces the number of synapses in the CNS and in the neuromuscular system. We also show that whereas some of the brain PC functions require PSA, others depend on PC per se. Our results show that PC, the second highly sialylated neural adhesion protein, plays multiple roles in neural development

Propuesta de Supply Chain Management y Logística para la empresa Biocombustibles sostenibles del Caribe S.A

Este documento está generalizado sobre Propuesta de supply chain management y logística para la empresa Biocombustibles Sostenibles del Caribe S.A. donde podemos entender como se manejan todos sus procesos de distribución basado en herramientas logística para su mejor desempeño, realizando investigaciones sobre sus procesos, producto y sus múltiples facetas en su buen servicio o cuales son sus metas y objetivos.This document is generalized about Supply chain management and logistics proposal for the company Biocombustibles Sostenibles del Caribe S.A. where we can understand how all their distribution processes are managed based on logistics tools for their best performance, conducting research on their processes, product and their multiple facets in their good service or what their goals and objectives are

Cell transformation assays for prediction of carcinogenic potential: State of the science and future research needs

Copyright @ 2011 The Authors. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.Cell transformation assays (CTAs) have long been proposed as in vitro methods for the identification of potential chemical carcinogens. Despite showing good correlation with rodent bioassay data, concerns over the subjective nature of using morphological criteria for identifying transformed cells and a lack of understanding of the mechanistic basis of the assays has limited their acceptance for regulatory purposes. However, recent drivers to find alternative carcinogenicity assessment methodologies, such as the Seventh Amendment to the EU Cosmetics Directive, have fuelled renewed interest in CTAs. Research is currently ongoing to improve the objectivity of the assays, reveal the underlying molecular changes leading to transformation and explore the use of novel cell types. The UK NC3Rs held an international workshop in November 2010 to review the current state of the art in this field and provide directions for future research. This paper outlines the key points highlighted at this meeting

The Large Aperture GRB Observatory

The Large Aperture GRB Observatory (LAGO) is aiming at the detection of the high energy (around 100 GeV) component of Gamma Ray Bursts, using the single particle technique in arrays of Water Cherenkov Detectors (WCD) in high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). WCD at high altitude offer a unique possibility of detecting low gamma fluxes in the 10 GeV - 1 TeV range. The status of the Observatory and data collected from 2007 to date will be presented.Comment: 4 pages, proceeding of 31st ICRC 200