5,983 research outputs found

    On the formation of tropical rings of atomic halogens: Causes and implications

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    Halogens produced by ocean biological and photochemical processes reach the tropical tropopause layer (TTL), where cold temperatures and the prevailing low ozone abundances favor the diurnal photochemical enhancement of halogen atoms. Under these conditions atomic bromine and iodine are modeled to be the dominant inorganic halogen species in the sunlit TTL, surpassing the abundance of the commonly targeted IO and BrO radicals. We suggest that due to the rapid photochemical equilibrium between halogen oxides and halogen atoms a natural atmospheric phenomenon evolves, which we have collectively termed >tropical rings of atomic halogens.> We describe the main causes controlling the modeled appearance and variability of these superposed rings of bare bromine and iodine atoms that circle the tropics following the Sun. Some potential implications for atmospheric oxidizing capacity are also explored. Our model results suggest that if experimentally confirmed, the extent and intensity of the halogen rings would directly respond to changes in oceanic halocarbon emissions, their atmospheric transport, and photochemistry.Peer Reviewe

    Phenomenology Tools on Cloud Infrastructures using OpenStack

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    We present a new environment for computations in particle physics phenomenology employing recent developments in cloud computing. On this environment users can create and manage "virtual" machines on which the phenomenology codes/tools can be deployed easily in an automated way. We analyze the performance of this environment based on "virtual" machines versus the utilization of "real" physical hardware. In this way we provide a qualitative result for the influence of the host operating system on the performance of a representative set of applications for phenomenology calculations.Comment: 25 pages, 12 figures; information on memory usage included, as well as minor modifications. Version to appear in EPJ

    Bromine partitioning in the tropical tropopause layer: Implications for stratospheric injection

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    © Author(s) 2014. Very short-lived (VSL) bromocarbons are produced at a prodigious rate by ocean biology and these source compounds (SGVSL), together with their inorganic degradation products (PGVSL), are lofted by vigorous convection to the tropical tropopause layer (TTL). Using a state-of-the-art photochemical mechanism within a global model, we calculate annual average stratospheric injection of total bromine due to VSL sources to be 5 pptv (parts per trillion by volume), with ∼ 3 pptv entering the stratosphere as PGVSL and ∼ 2 pptv as SGVSL. The geographic distribution and partitioning of VSL bromine within the TTL, and its consequent stratospheric injection, is highly dependent on the oceanic flux, the strength of convection and the occurrence of heterogeneous recycling reactions. Our calculations indicate atomic Br should be the dominant inorganic species in large regions of the TTL during daytime, due to the low ozone and cold conditions of this region. We propose the existence of a >tropical ring of atomic bromine> located approximately between 15 and 19 km and between 30°N and 30°S. Daytime Br / BrO ratios of up to ∼ 4 are predicted within this inhomogeneous ring in regions of highly convective transport, such as the tropical Western Pacific. Therefore, we suggest that experimental programs designed to quantify the bromine budget of the TTL and the stratospheric injection of VSL biogenic bromocarbons should include a strategy for the measurement of atomic Br during daytime as well as HOBr and BrCl during nighttime.Peer Reviewe

    Análisis bibliométrico de la producción científica peruana en cardiología y medicina cardiovascular

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    Objective. To determine the characteristics and trend of the articles published on cardiology and cardiovascular medicine in the Peruvian context, and to understand how it has changed over the years. Materials and methods. A bibliometric study of original articles published up to 2020 by Peruvian authors in journals indexed under the category “Cardiac & Cardiovascular Systems” in Web of Science (WOS) was performed. The articles were included according to the selection criteria in the Rayyan web application and the bibliometric analysis was performed using the Bibliometrix package in the R programming language and VOSviewer. Results. A total of 159 published articles were included, and an increase in the number of publications since 2015 was observed. The most cited article was a clinical trial by Fitchett et al. and published in 2016. Miranda JJ was the Peruvian author with the highest number of published articles followed by Hernández AV and Málaga G. The institutional affiliation with the highest number of original articles was Universidad Peruana Cayetano Heredia. Regarding the terms or keywords, it was found that most of the published studies had terms related to epidemiology, while in the most recent articles, the terms were related to outcomes or specific interventions that are used in clinical studies. Conclusions. In the last five years, there has been an increase in the scientific production on cardiology and cardiovascular medicine by authors with Peruvian institutional affiliation, with a greater production from the Universidad Peruana Cayetano Heredia. The journal with the highest number of publications by authors with Peruvian institutional affiliation on cardiology and cardiovascular medicine was Circulation, where two of the most cited articles with Peruvian institutional affiliation were also found.Objetivo. Determinar las características y la tendencia de los artículos publicados sobre cardiología y medicina cardiovascular en el contexto peruano, y comprender cómo ha cambiado a lo largo de los años. Materiales y métodos. Se realizó un estudio bibliométrico de artículos originales publicados hasta el año 2020 por autores peruanos en revistas indexadas bajo la categoría «Cardiac & Cardiovascular Systems» en Web of Science (WOS). Se incluyeron los artículos según los criterios de selección en el aplicativo web Rayyan y se realizó el análisis bibliométrico mediante el paquete Bibliometrix en el lenguaje de programación R y VOSviewer. Resultados. Se incluyeron 159 artículos publicados, y se observó un incremento del número de publicaciones desde 2015. El artículo más citado fue un ensayo clínico realizado por Fitchett et al. y publicado en 2016. Miranda JJ fue el autor peruano con mayor número artículos publicados seguido de Hernández AV y Málaga G. La filiación institucional con mayor número de artículos originales fue la Universidad Peruana Cayetano Heredia. En cuanto a los términos o palabras clave, se encontró que la mayor cantidad de estudios publicados contaban con términos relacionados con la epidemiología, mientras que en los artículos más recientes, los términos se relacionaron con desenlaces o intervenciones específicas que son utilizados en estudios clínicos. Conclusiones. Se encontró un incremento en los últimos cinco años en la producción científica sobre cardiología y medicina cardiovascular de autores con filiación institucional peruana, con una mayor producción de la Universidad Peruana Cayetano Heredia. La revista con mayores publicaciones de autores con filiación institucional peruana sobre cardiología y medicina cardiovascular fue Circulation, donde también se encontraron dos de los artículos con filiación institucional peruana más citados

    Expression of the alpha-thionin gene from barley in tobacco confers enhanced resistance to bacterial pathogens

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    Thionins are cysteine-rich, 5 kDa polypeptides which are toxic to plant pathogens in vitro. Expression of the gene encoding alpha-thionin from barley endosperm, under the 35S promoter from cauliflower mosaic virus, conferred to transgenic tobacco enhanced resistance to the bacterial plant pathogens Pseudomonas syringae pv. tabaci 153 and P. syringae pv. syringae. The barley alpha-thionin gene, which has two introns, was correctly spliced in tobacco. The alpha-thionin in transgenic plants had the expected mobility in the gradient, when separated by high- performance liquid chromatography, reacted with monospecific antibodies and showed the expected antibiotic properties in vitr

    Sensitivity analysis of a stress strain model for steel fiber reinforced concrete plates

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    p. 2941-2954This article deals with the sensitivity study of a given model for the behavior of thin laminar elements of SFRC (steel fiber reinforced concrete). In order to carry out this analysis, a brief description of the model used for the behavior of the SFRC in laminar elements is presented. The analysis was made by means of ABAQUS finite element software with a particular model for the behavior of SFRC. The limit of the fragile-plastic behavior of SFRC plates has been established as an outcome of the analysis. The results of test performed on plates were compared with the numerical simulation. Good correlation between experimental results and those obtained in the numerical simulation was observed as an adequate support for the model.Lopez-Gayarre, F.; Serrano, MA.; Lázaro Fernández, CM.; Domingo Cabo, A.; Pelufo Carbonell, MJ. (2009). Sensitivity analysis of a stress strain model for steel fiber reinforced concrete plates. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/668

    The International Working Group on Neurotransmitter related Disorders (iNTD): A worldwide research project focused on primary and secondary neurotransmitter disorders

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    INTRODUCTION: Neurotransmitters are chemical messengers that enable communication between the neurons in the synaptic cleft. Inborn errors of neurotransmitter biosynthesis, breakdown and transport are a group of very rare neurometabolic diseases resulting in neurological impairment at any age from newborn to adulthood. METHODS AND RESULTS: The International Working Group on Neurotransmitter related Disorders (iNTD) is the first international network focusing on the study of primary and secondary neurotransmitter disorders. It was founded with the aim to foster exchange and improve knowledge in the field of these rare diseases. The newly established iNTD patient registry for neurotransmitter related diseases collects longitudinal data on the natural disease course, approach to diagnosis, therapeutic strategies, and quality of life of affected patients. The registry forms the evidence base for the development of consensus guidelines for patients with neurotransmitter related disorders. CONCLUSION: The iNTD network and registry will improve knowledge and strengthen research capacities in the field of inborn neurotransmitter disorders. The evidence-based guidelines will facilitate standardized diagnostic procedures and treatment approaches

    Development of plant-based burgers using gelled emulsions as fat source and beetroot juice as colorant: Effects on chemical, physicochemical, appearance and sensory characteristics

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    fat source and, beetroot juice (fresh and commercial) as colorant ingredient and to assess their quality properties. Burgers with low fat content (<3%) and remarkable protein (18.6–19.5%) and dietary fiber content (14.5–16.2%) were obtained. The use of GE allows improving their lipid profile being PUFAs the main fraction (>57%, PUFA/SFA >4.5, n-6/n-3 40%) depending on the GE used: α-linolenic in the case of chia-GE and linoleic when hemp-GE was used. The use of beetroot fresh juice allows to obtain burgers with a redness similar to that of traditional meat burgers (16–21), with higher betalains content (27–38 mg/100 g dw) but more susceptible to color changes during cooking than when commercial juice was used. Plant-based burgers suffer less cooking loss (14–17%) and dimensional changes (shrinkage 3–5% and not thickness increase) than reported for traditional meat burgers. According to the results of sensory evaluation, although all plant-based burgers were scored with a good overall acceptability, it could be enhanced by the ingredient optimization because each of the ingredients studied either improved or worsened the different attributes assessed

    Genome-Wide Methylation Profiling in the Thalamus of Scrapie Sheep

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    Scrapie is a neurodegenerative disorder belonging to the group of transmissible spongiform encephalopathy (TSE). Scrapie occurs in sheep and goats, which are considered good natural animal models of these TSE. Changes in DNA methylation occur in the central nervous system (CNS) of patients suffering from prion-like neurodegenerative diseases, such as Alzheimer''s disease. Nevertheless, potential DNA methylation alterations have not yet been investigated in the CNS of any prion disease model or naturally infected cases, neither in humans nor in animals. Genome-wide DNA methylation patterns were studied in the thalamus obtained from sheep naturally infected with scrapie at a clinical stage (n = 4) and from controls (n = 4) by performing a whole-genome bisulfite sequencing (WGBS) analysis. Ewes carried the scrapie-susceptible ARQ/ARQ PRNP genotype and were sacrificed at a similar age (4–6 years). Although the average genomic methylation levels were similar between the control and the scrapie animals, we identified 8, 907 significant differentially methylated regions (DMRs) and 39 promoters (DMPs). Gene Ontology analysis revealed that hypomethylated DMRs were enriched in genes involved in transmembrane transport and cell adhesion, whereas hypermethylated DMRs were related to intracellular signal transduction genes. Moreover, genes highly expressed in specific types of CNS cells and those previously described to be differentially expressed in scrapie brains contained DMRs. Finally, a quantitative PCR (qPCR) validation indicated differences in the expression of five genes (PCDH19, SNCG, WDR45B, PEX1, and CABIN1) that matched the methylation changes observed in the genomic study. Altogether, these results suggest a potential regulatory role of DNA methylation in prion neuropathology. Copyright © 2022 Hernaiz, Sanz, Sentre, Ranera, Lopez-Pérez, Zaragoza, Badiola, Filali, Bolea, Toivonen and Martín-Burriel
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