Coordination-driven magnetic-to-nonmagnetic transition in manganese doped silicon clusters

The interaction of a single manganese impurity with silicon is analyzed in a combined experimental and theoretical study of the electronic, magnetic, and structural properties of manganese-doped silicon clusters. The structural transition from exohedral to endohedral doping coincides with a quenching of high-spin states. For all geometric structures investigated, we find a similar dependence of the magnetic moment on the manganese coordination number and nearest neighbor distance. This observation can be generalized to manganese point defects in bulk silicon, whose magnetic moments fall within the observed magnetic-to-nonmagnetic transition, and which therefore react very sensitively to changes in the local geometry. The results indicate that high spin states in manganese-doped silicon could be stabilized by an appropriate lattice expansion

Significado de la anemia en las diferentes etapas de la vida

Overview: Anemia is very common in primary care consultations and pediatrics, and IDA is the cause of 50% of all cases of anemia. Methodology: Literature review and documentary descriptive analysis of the pathogenesis of iron-deficiency anemia, the basic diagnostic tests to study IDA and the significance of such using a specific time period in the documentary search and inclusion criteria that takes into account factors that are analyzed in the study: Ideas about the metabolism of iron. Ideas about hematopoiesis. Laboratory diagnosis and classification of anemia. Clinical features of iron deficiency anemia. Causes of iron deficiency. Results and conclusion: The staged documentary study covers the publications on the pathogenesis of iron deficiency anemia, the basic diagnostic tests to study the IDA and the significance of such, and it shows how important this data is for professional nursing in the area of primary care and pediatrics, to identify it and act accordingly.Resumen: La anemia presenta una elevada prevalencia en las consultas de atención primaria y pediatría, y la ADH representa el 50% de todos los casos de anemia. Metodología: Revisión bibliográfica y análisis descriptivo documental sobre etiopatogenia de la anemia ferropénica, las pruebas diagnósticas básicas para el estudio de la ADH  y su significado, utilizando una temporalidad determinada en la búsqueda documental y criterios de inclusión atendiendo a las dimensiones que se analizan en el estudio: Nociones acerca del metabolismo del hierro. Nociones acerca de la hematopoyesis. Diagnóstico por el laboratorio y clasificación de las anemias. Clínica de la anemia ferropénica. Causas de la deficiencia de hierro. Resultados y conclusión: EL estudio documental efectuado nos presenta la existencia de publicaciones con contenidos sobre etiopatogenia de la anemia ferropénica, las pruebas diagnósticas básicas para el estudio de la ADH  y su significado, evidenciando la importancia de este contenido para el profesional de enfermería en el área de la atención primaria y pediatría

Gene expression varies within and between enzootic and epizootic lineages of Batrachochytrium dendrobatidis (Bd) in the Americas

While much research focus is paid to hypervirulent fungal lineages during emerging infectious disease outbreaks, examining enzootic pathogen isolates can be equally fruitful in delineating infection dynamics and determining pathogenesis. The fungal pathogen of amphibians, Batrachochytrium dendrobatidis (Bd), exhibits markedly different patterns of disease in natural populations, where it has caused massive amphibian declines in some regions, yet persists enzootically in others. Here we compare in vitro gene expression profiles of a panel of Bd isolates representing both the enzootic Bd-Brazil lineage, and the more recently diverged, panzootic lineage, Bd-GPL. We document significantly different lineage-specific and intralineage gene expression patterns, with Bd-Brazil upregulating genes with aspartic-type peptidase activity, and Bd-GPL upregulating CBM18 chitin-binding genes, among others. We also find pronounced intralineage variation in membrane integrity and transmembrane transport ability within our Bd-GPL isolates. Finally, we highlight unexpectedly divergent expression profiles in sympatric panzootic isolates, underscoring microgeographic functional variation in a largely clonal lineage. This variation in gene expression likely plays an important role in the relative pathogenesis and host range of Bd-Brazil and Bd-GPL isolates. Together, our results demonstrate that functional genomics approaches can provide information relevant to studies of virulence evolution within the Bd Glade12413443The authors thank Joyce Longcore for providing the Bd isolates used in this study, Miranda Gray for assistance in the laboratory, Ezra Lencer for feedback on methods, the Cornell Biotechnology Resource Center for sequencing and bioinformatics troubleshooting, and Zamudio lab members for helpful manuscript comments. This work was funded by the National Science Foundation (NSF) (grant DEB 1120249) and the Cornell Center for Vertebrate Genomic

The census of interstellar complex organic molecules in the Class I hot corino of SVS13-A

We present the first census of the interstellar Complex Organic Molecules (iCOMs) in the low-mass Class I protostar SVS13-A, obtained by analysing data from the IRAM-30m Large Project ASAI (Astrochemical Surveys At IRAM). They consist of an high-sensitivity unbiased spectral survey at the 1mm, 2mm and 3mm IRAM bands. We detected five iCOMs: acetaldehyde (CH$_3$CHO), methyl formate (HCOOCH$_3$), dimethyl ether (CH$_3$OCH$_3$), ethanol (CH$_3$CH$_2$OH) and formamide (NH$_2$CHO). In addition we searched for other iCOMs and ketene (H$_2$CCO), formic acid (HCOOH) and methoxy (CH$_3$O), whose only ketene was detected. The numerous detected lines, from 5 to 37 depending on the species, cover a large upper level energy range, between 15 and 254 K. This allowed us to carry out a rotational diagram analysis and derive rotational temperatures between 35 and 110 K, and column densities between $3\times 10^{15}$ and $1\times 10^{17}$ cm$^{-2}$ on the 0."3 size previously determined by interferometric observations of glycolaldehyde. These new observations clearly demonstrate the presence of a rich chemistry in the hot corino towards SVS13-A. The measured iCOMs abundances were compared to other Class 0 and I hot corinos, as well as comets, previously published in the literature. We find evidence that (i) SVS13-A is as chemically rich as younger Class 0 protostars, and (ii) the iCOMs relative abundances do not substantially evolve during the protostellar phase.Comment: 24 pages, MNRAS in pres

Tetrapandins, a New Class of Scorpion Toxins That Specifically Inhibit Store-operated Calcium Entry in Human Embryonic Kidney-293 Cells

Venoms from 14 snakes and four scorpions were screened for inhibitory activities toward store-operated Ca2+ entry (SOCE) in human embryonic kidney-293 cells. An inhibitory activity was found in venom from the African scorpion Pandinus imperator. The active agent of this venom was purified by gel filtration and reverse-phase high pressure liquid chromatography methods. Sequence information on the purified fraction, by automatic Edman degradation and mass spectrometry analysis, identified the activity as being contained in two tetrapeptides, which we have named tetrapandins. We demonstrate that synthesized tetrapandins have inhibitory activity for SOCE in human embryonic kidney-293 cells while having no effect on either thapsigargin- or carbachol-stimulated release of Ca2+ stores. These toxins should be extremely useful in future studies to determine downstream events regulated by SOCE as well as to determine whether multiple pathways exist for thapsigargin-stimulated Ca2+ entry

Assessment of shelf sea tides and tidal mixing fronts in a global ocean model

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148272/1/ocemod_2019_shelftidesandfronts_timkoetal.pdfDescription of ocemod_2019_shelftidesandfronts_timkoetal.pdf : Main articl

Modification of the Physical Properties of a Nafion Film Due to Inclusion of n-Dodecyltriethylammonium Cation: Time Effect.

This study investigates the effects of modifying commercial Nafion-212 thin films with dodecyltriethylammonium cation (DTA+) on their electrical resistance, elastic modulus, light transmission/reflection and photoluminescence properties. The films were modified through a proton/cation exchange process for immersion periods ranging from 1 to 40 h. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were employed to analyze the crystal structure and surface composition of the modified films. The electrical resistance and the different resistive contributions were determined via impedance spectroscopy. Changes in the elastic modulus were evaluated using stress–strain curves. Additionally, optical characterization tests, including light/reflection (250–2000 nm) and photoluminescence spectra, were also performed on both unmodified and DTA+-modified Nafion films. The results reveal significant changes in the electrical, mechanical and optical properties of the films, depending on the exchange process time. In particular, the inclusion of the DTA+ into the Nafion structure improved the elastic behavior of the films by significantly decreasing the Young modulus. Furthermore, the photoluminescence of the Nafion films was also enhanced. These findings can be used to optimize the exchange process time to achieve specific desired properties.Partial funding for open access charge: Universidad de Málag

Measuring Transit Signal Recovery in the Kepler Pipeline. III. Completeness of the Q1-Q17 DR24 Planet Candidate Catalogue, with Important Caveats for Occurrence Rate Calculations

With each new version of the Kepler pipeline and resulting planet candidate catalogue, an updated measurement of the underlying planet population can only be recovered with an corresponding measurement of the Kepler pipeline detection efficiency. Here, we present measurements of the sensitivity of the pipeline (version 9.2) used to generate the Q1-Q17 DR24 planet candidate catalog (Coughlin et al. 2016). We measure this by injecting simulated transiting planets into the pixel-level data of 159,013 targets across the entire Kepler focal plane, and examining the recovery rate. Unlike previous versions of the Kepler pipeline, we find a strong period dependence in the measured detection efficiency, with longer (>40 day) periods having a significantly lower detectability than shorter periods, introduced in part by an incorrectly implemented veto. Consequently, the sensitivity of the 9.2 pipeline cannot be cast as a simple one-dimensional function of the signal strength of the candidate planet signal as was possible for previous versions of the pipeline. We report on the implications for occurrence rate calculations based on the Q1-Q17 DR24 planet candidate catalog and offer important caveats and recommendations for performing such calculations. As before, we make available the entire table of injected planet parameters and whether they were recovered by the pipeline, enabling readers to derive the pipeline detection sensitivity in the planet and/or stellar parameter space of their choice.Comment: 8 pages, 5 figures, full electronic version of Table 1 available at the NASA Exoplanet Archive; accepted by ApJ May 2nd, 201

Análisis por elementos finitos de una prótesis transtibial para un ciclista paralímpico

(Eng) Currently, finite element analysis techniques are used to reduce costs in the manufacturing process of sports prostheses. This study primarily focuses on the finite element analysis of a design for a transtibial prosthesis for a paralympic cyclist, integra ting the biomechanics of an athlete with a double leg amputation below the knee with two prostheses categorized before the Union Cycling International (UCI) with a C - 3 disability and the characteristics of the terrain and the dynamic model. The analysis em ploying finite elements aims to evaluate the static and dynamic behavior of the proposed design when subjected to competition in the track - cycling category. As a result of this analysis, mechanical aspects, such as static forces, buckling, frequency, fatig ue, free fall, impact, and aerodynamics, can be evaluated to verify that the design of the proposed transtibial prosthesis meets an adequate aerodynamic profile and its mechanical characteristics are suitable to be used in a high - performance Paralympic cyc ling competition.(Spa) En la actualidad se emplean técnicas de análisis por elementos finitos para reducir costos en el proceso de fabricación de prótesis deportivas. Este estudio particularmente se centra en el análisis por elementos finitos de un diseño para una prótesis transtibial de un ciclista paralímpico, en el que se integra la biomecánica de un atleta con amputación en ambas piernas por debajo de la rodilla, con dos prótesis categorizado ante la Unión Ciclista Internacional (UCI) con una discapacidad de grado C-3, considerando características del terreno y el modelo dinámico. El análisis por medio de elementos finitos tiene como objetivo evaluar el comportamiento estático y dinámico del diseño propuesto cuando se somete a una competencia en la categoría de ciclismo de pista. Como resultado de este análisis, se pueden evaluar aspectos mecánicos como: esfuerzos estáticos, pandeo, frecuencia, fatiga, caída libre, impacto y aerodinámica, permitiendo verificar que el diseño de la prótesis transtibial propuesto cumple con un perfil aerodinámico idóneo y sus características mecánicas para ser utilizada en una competencia de ciclismo paralímpico de alto rendimiento