Lattice dynamics of Sb2Te3 at high pressures

We report an experimental and theoretical lattice dynamics study of antimony telluride (Sb 2Te 3) up to 26 GPa together with a theoretical study of its structural stability under pressure. Raman-active modes of the low-pressure rhombohedral (R-3m) phase were observed up to 7.7 GPa. Changes of the frequencies and linewidths were observed around 3.5 GPa where an electronic topological transition was previously found. Raman-mode changes evidence phase transitions at 7.7, 14.5, and 25GPa. The frequencies and pressure coefficients of the new phases above 7.7 and 14.5 GPa agree with those calculated for the monoclinic C2/m and C2/c structures recently observed at high pressures in Bi 2Te 3 and also for the C2/m phase in the case of Bi 2Se 3 and Sb 2Te 3. Above 25 GPa no Raman-active modes are observed in Sb 2Te 3, similarly to the case of Bi 2Te 3 and Bi 2Se 3. Therefore, it is possible that the structure of Sb 2Te 3 above 25 GPa is the same disordered bcc phase already found in Bi 2Te 3 by x-ray diffraction studies. Upon pressure release, Sb 2Te 3 reverts back to the original rhombohedral phase after considerable hysteresis. Raman- and IR-mode symmetries, frequencies, and pressure coefficients in the different phases are reported and discussed. © 2011 American Physical Society.This work has been done under financial support from Spanish MICINN under Project Nos. MAT2010-21270-C04-03/04 and CSD-2007-00045 and supported by the Ministry of Education, Youth and Sports of the Czech Republic (MSM 0021627501). E. P.-G. acknowledges the financial support of the Spanish MEC under a FPI fellowship. Supercomputer time has been provided by the Red Espanola de Supercomputacion (RES) and the MALTA cluster.Gomis Hilario, O.; Vilaplana Cerda, RI.; Manjón Herrera, FJ.; Rodríguez-Hernández, P.; Pérez-González, E.; Muñoz, A.; Kucek, V.... (2011). 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A., … Burke, K. (2008). Restoring the Density-Gradient Expansion for Exchange in Solids and Surfaces. Physical Review Letters, 100(13). doi:10.1103/physrevlett.100.136406Mujica, A., Rubio, A., Muñoz, A., & Needs, R. J. (2003). High-pressure phases of group-IV, III–V, and II–VI compounds. Reviews of Modern Physics, 75(3), 863-912. doi:10.1103/revmodphys.75.863Blanco, M. A., Francisco, E., & Luaña, V. (2004). GIBBS: isothermal-isobaric thermodynamics of solids from energy curves using a quasi-harmonic Debye model. Computer Physics Communications, 158(1), 57-72. doi:10.1016/j.comphy.2003.12.001Cardona, M. (2004). Phonon widths versus pressure. High Pressure Research, 24(1), 17-23. doi:10.1080/08957950310001635819Cardona, M. (2004). Effects of pressure on the phonon–phonon and electron–phonon interactions in semiconductors. physica status solidi (b), 241(14), 3128-3137. doi:10.1002/pssb.200405202Ulrich, C., Mroginski, M. A., Goñi, A. 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Gregariousness in the giant sloth Lestodon (Xenarthra): multi-proxy approach of a bonebed from the Last Maximum Glacial of Argentine Pampas

Megamammals constituted an important component in the Pleistocene faunal communities of South America. Paleobiological and paleoecological studies involving different megamammal taxa have increased significantly in the last years, but there are still several poorly-known issues of its life history. In this work, we analyze an assemblage composed of 13 individuals of different ontogenetic stages, and possibly different sex, belonging to the giant ground sloth Lestodon armatus (Xenarthra, Folivora), recovered from Playa del Barco site (Pampean Region, Argentina). A dating of 19,849 years Cal BP allows assigning this assemblage to a period of the MIS (Marine Isotope Stage) 2 related to the end of the Last Glacial Maximum. Based on multiple lines of research (e.g. taphonomy, paleopathology, osteohistology, isotopy), we interpret the origin of the assemblage and diverse paleobiological and paleoecological aspects (e.g. social behavior, ontogenetic changes, sexual dimorphism, diseases, resource and habitat use, trophic relationships) of L. armatus. Evidence suggests that the assemblage was formed by a local single event of catastrophic mortality, which affected different members of a social group. This record represents the first accurate evidence of gregariousness for this ground sloth, providing new data on a poorly-known behavior among extinct Folivora

TOX3 rs3803662 Polymorphism Is Associated With Breast Cancer Protection In Northeastern Mexican Woman

Introduction: Low penetrance genes are involved in breast cancer (BC) and confer risk for the development of this neoplasia. Different single nucleotide polymorphisms (SNPs) associated with BC have been identified, such as rs3803662 (TOX3), which is related to estrogen receptors in European and African-American women. The contribution of this variant in the Mexican population is unknown. The objective of this study was to evaluate, through a case-control design, the association of the SNP rs3803662 (TOX3), with the risk of BC in women from northeastern Mexico. Methods: We included 434 cases and 228 controls. Genotyping was carried out using RFLPs. The SPSS 7.0 statistical program was used to determine the gene frequencies, the estimation of the relative risk (Odds ratio [OR]), and the Hardy-Weinberg equilibrium (EHW). Results: The homocygote (T/T) genotype of the SNP TOX3 rs3803662 was identified as a protective allele for BC (OR: 0.47, 95% CI: 0.29 - 0.78). Conclusions; The T allele of the SNP rs3803662 can be considered as a protective factor for BC from northeastern Mexico women

Efecto de la inclusión de aceite de oliva lampante en la dieta de ovejas sobre el perfil de ácidos grasos de leche y queso

The objective of this experiment was to evaluate the effect of a dietary supplementation of lampant olive oil on the fatty aid profiles of the milk and cheese of ewes. Nine lactating ewes were used in a 3 × 3 Latin square design. Dietary treatments were supplemented with 0 (control; T0), 36 (T1) and 88 (T2) g of lampante olive oil/kg of dry matter intake (DM). DM, milk yield and milk composition (fat and protein) were not affected by dietary treatments. Oleic and vaccenic acids gradually increased (P < 0.05) and the saturated FA and atherogenicity index decreased (P < 0.05) in milk and cheese as the concentration of lampante olive oil was increased in dietary rations. Overall, the supplementation of lampante olive oil in the diets of lactating ewes increased monounsaturated FA and decreased saturated FA concentrations in milk and cheese, thus improving their quality from the human health standpoint.El objetivo de este estudio fue evaluar el efecto de la inclusión de aceite de oliva lampante en la dieta de ovejas sobre el perfil de ácidos grasos de leche y queso. Nueve ovejas fueron utilizadas en un diseño de CuadradoLatino 3 × 3. Las dietas fueron suplementadas con 0 (control; T0), 36 (T1) y 88 (T2) g de aceite de oliva lampante por kg de materia seca de alimento. La ingesta, la producción de leche y la composición de leche (grasa y proteína) no se vieron afectados por los tratamientos. Los ácidos oleico y vaccénico incrementaron (P < 0.05) gradualmente mientras que los ácidos grasos saturados y el índice aterogénico disminuyeron (P < 0.05) en leche y queso a medida que la inclusión de aceite de oliva lampante se incrementó en la dieta. En conclusión, la inclusión de aceite de oliva lampante en dietas de ovejas lactantes aumenta la concentración de ácidos grasos monoinsaturados y disminuye la de los saturados en leche y queso con posibles efectos benéficos sobre la salud humana

Evidence‐based treatment for gynoid lipodystrophy: A review of the recent literature

Resumen La lipodistrofia ginoide (LDG) es una alteracion estructural, inflamatoria y bioquımica del tejido subcutaneo que causa modificaciones topograficas en la piel. Conocida comunmente como “celulitis”, la LDG afecta hasta a 90% de las mujeres, practicamente en todas las etapas de la vida, iniciando en la pubertad. Se trata de una condicion que afecta considerablemente la calidad de vida de quien la padece. Es motivo frecuente de consulta aunque las pacientes recurren a tratamientos empıricos, improvisados, sin bases ni evidencia cientıfica, los cuales desmotivan y producen frustracion no solo por su falta de resultados, sino por complicaciones derivadas de dichos tratamientos. Un grupo de expertos de diversas especialidades involucradas en el manejo de este problema presenta en este artıculo el resultado de una busqueda bibliografica sistematica y de la discusion consensuada de la evidencia obtenida de diversos tratamientos disponibles actualmente. El analisis se dividio en tratamientos topicos, tratamientos sistemicos, tratamientos no invasivos y tratamientos mınimamente invasivos

Experimental and Theoretical Study of Bi2O2Se Under Compression

[EN] We report a joint experimental and theoretical study of the structural, vibrational, elastic, optical, and electronic properties of the layered high-mobility semiconductor Bi2O2Se at high pressure. A good agreement between experiments and ab initio calculations is observed for the equation of state, the pressure coefficients of the Raman-active modes and the bandgap of the material. In particular, a detailed description of the vibrational properties is provided. Unlike other Sillen-type compounds which undergo a tetragonal to collapsed tetragonal pressure-induced phase transition at relatively low pressures, Bi2O2Se shows a remarkable structural stability up to 30 GPa; however, our results indicate that this compound exhibits considerable electronic changes around 4 GPa, likely related to the progressive shortening and hardening of the long and weak Bi-Se bonds linking the Bi2O2 and Se atomic layers. Variations of the structural, vibrational, and electronic properties induced by these electronic changes are discussed.This work was supported by Brazilian Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) under project 201050/2012-9, by Spanish MINECO projects MAT2015-71070-REDC, MAT2016-75586-C4-1/2/3-P and CTQ2015-65207-P and by the Grant Agency of the Czech Republic (GA CR) under project 16-07711S. Supercomputer time has been provided by the Red Espanola de Supercomputacion (RES) and the MALTA cluster. D.S.-P. and J.A.S. acknowledge the "Ramon y Cajal" fellowship program (RYC-2015-17482) and Spanish Mineco Projects (2014-15643 and 2017-83295-P). J.R.-F. acknowledge the "Juan de la Cierva" program (IJCI-2014-20513) for financial support.Pereira, A.; Santamaría Pérez, D.; Ruiz Fuertes, J.; Manjón, F.; Cuenca Gotor, VP.; Vilaplana Cerda, RI.; Gomis, O.... (2018). Experimental and Theoretical Study of Bi2O2Se Under Compression. The Journal of Physical Chemistry C. 122(16):8853-8867. https://doi.org/10.1021/acs.jpcc.8b02194S885388671221

In Vitro Evaluation of Colloidal Silver on Immune Function: Antilymphoproliferative Activity

Colloidal silver (AgC) is currently used by humans and it can be internalized through inhalation, injection, ingestion, and dermal contact. However, there is limited information about immunological activity; more investigations using colloidal silver are needed. In the present study, the effects of AgC (17.5 ng/mL) on immunological parameters (proliferation and immunophenotyping) using human peripheral blood mononuclear cells (PBMC) and macrophages (phagocytosis) and cytotoxicity on leukemia and lymphoma cancer cell lines (1.75 to 17.5 ng/mL) were investigated. AgC was observed to significantly (p<0.05) decrease interleukin-2 (IL-2) production and proliferation induced by phytohemagglutinin or concanavalin A in PBMC without affecting its cell viability but with cytotoxic effect on cancer cells. IL-2, IL-4, IL-6, IL-10, INF-γ, and IL-17A cytokines production and CD3+, CD3−CD19+, CD3+CD4+, CD3+CD8+, and CD16+CD56+ PBMC phenotypes were not affected by AgC. The present study demonstrates that colloidal silver is harmless and nontoxic to the immune system cells and its ability to interfere with the immune response by decreasing cell proliferation when stimulated with mitogens demonstrated the antilymphoproliferative potential of AgC

The Pierre Auger Observatory Open Data

The Pierre Auger Collaboration has embraced the concept of open access to their research data since its foundation, with the aim of giving access to the widest possible community. A gradual process of release began as early as 2007 when 1% of the cosmic-ray data was made public, along with 100% of the space-weather information. In February 2021, a portal was released containing 10% of cosmic-ray data collected from 2004 to 2018, during Phase I of the Observatory. The Portal included detailed documentation about the detection and reconstruction procedures, analysis codes that can be easily used and modified and, additionally, visualization tools. Since then the Portal has been updated and extended. In 2023, a catalog of the 100 highest-energy cosmic-ray events examined in depth has been included. A specific section dedicated to educational use has been developed with the expectation that these data will be explored by a wide and diverse community including professional and citizen-scientists, and used for educational and outreach initiatives. This paper describes the context, the spirit and the technical implementation of the release of data by the largest cosmic-ray detector ever built, and anticipates its future developments.Comment: 19 pages, 8 figure

Radio Measurements of the Depth of Air-Shower Maximum at the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA), part of the Pierre Auger Observatory, is currently the largest array of radio antenna stations deployed for the detection of cosmic rays, spanning an area of $17$ km$^2$ with 153 radio stations. It detects the radio emission of extensive air showers produced by cosmic rays in the $30-80$ MHz band. Here, we report the AERA measurements of the depth of the shower maximum ($X_\text{max}$), a probe for mass composition, at cosmic-ray energies between $10^{17.5}$ to $10^{18.8}$ eV, which show agreement with earlier measurements with the fluorescence technique at the Pierre Auger Observatory. We show advancements in the method for radio $X_\text{max}$ reconstruction by comparison to dedicated sets of CORSIKA/CoREAS air-shower simulations, including steps of reconstruction-bias identification and correction, which is of particular importance for irregular or sparse radio arrays. Using the largest set of radio air-shower measurements to date, we show the radio $X_\text{max}$ resolution as a function of energy, reaching a resolution better than $15$ g cm$^{-2}$ at the highest energies, demonstrating that radio $X_\text{max}$ measurements are competitive with the established high-precision fluorescence technique. In addition, we developed a procedure for performing an extensive data-driven study of systematic uncertainties, including the effects of acceptance bias, reconstruction bias, and the investigation of possible residual biases. These results have been cross-checked with air showers measured independently with both the radio and fluorescence techniques, a setup unique to the Pierre Auger Observatory.Comment: Submitted to Phys. Rev.