1,067 research outputs found

    Beltrandoite, a new root-name in the högbomite supergroup: the Mg end-member magnesiobeltrandoite-2N3S

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    Magnesiobeltrandoite-2N3S, ideally Mg6Al20Fe3+2 O38(OH)2, is a new member of the h\uf6gbomite supergroup of minerals. It occurs in magnesian chloritites of a metamorphosed layered mafic complex in the Etirol-Levaz continental slice, middle Valtournenche, Aosta Valley, Italy. Magnesiobeltrandoite-2N3S grows in a fine-grained chlorite matrix associated as inclusions to relict pre-Alpine hercynite spinels and dolomite in cm- to dm-long darker boudins, which are cut by corundum\ufeclinochlore \ub1 dolomite veins. It occurs as subhedral to euhedral black crystals ( 3c50\u2013400mm), dark reddish-brown in thin section. It shows dark brown streak and vitreous lustre. It is brittle, with no cleavage observed and uneven fracture. Mohs hardness 486\u20136\ubd. Dcalc = 3.93 g \ub7 cm3. It shows no fluorescence under UV radiation and no cathodoluminescence. The mineral is optically uniaxial (\u2013) with an estimated mean refractive index of ca. 1.80. Pleochroism is weak with e = deep reddish brown (along c axis) and v = reddish brown ( a5 c). Absorption is E > O. The Raman spectrum shows a weak and strongly polarized broad OH-characteristic absorption centred at 3364 cm1. Electron microprobe analysis combined with Synchrotron M\uf6ssbauer source spectrometry yielded the following empirical formula based on 40 anions per formula unit (pfu) [Al18.36Mg3.96Fe2+2:52Fe3+2:08Ti0.56Cr0.40Zn0.06V3+0.03Mn0.02]S28O38(OH)2. The ideal formula is Mg6Al20Fe3+2O38(OH)2.The eight strongest lines in the X-ray powder diffraction pattern are [dobs/A (I) (h k l)]: 2.858 (42) (1 1 0), 2.735 (51) (1 0 7), 2.484 (46) (0 1 8), 2.427 (100) (1 1 5), 1.568 (29) (1 2 8), 1.514 (30) (0 2 12), 1.438 (42) (2 0 13), and 1.429 (72) (2 2 0). The crystal structure of magnesiobeltrandoite-2N3S [P3m1, a = 5.7226(3), c = 23.0231(9)A, V = 652.95(5)A 3] was refined from X-ray single-crystal data to R1 = 0.022; it is isostructural with magnesioh\uf6gbomite-2N3S

    Assessment of the proportionality of skin folds between professional footballers and alternate, Peruvian

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    El objetivo del estudio fue proporcionar información descriptiva sobre las diferencias de proporcionalidad de la masa corporal y pliegues cutáneos entre jugadores titulares y reservas en función de la posición de juego. Fueron seleccionados de forma no probabilística 4 clubes profesionales de Primera División del Fútbol Profesional Peruano, considerándose 44 titulares y 28 reservas. Se evaluó la masa corporal, estatura, seis pliegues cutáneos, determinándose la proporcionalidad corporal por medio de la estrategia del Phantom. Los resultados muestran que la proporcionalidad de la masa corporal y los pliegues cutáneos es similar, tanto de forma general y por ubicación de juego, no existiendo diferencias significativas entre las posiciones de juego y entre titulares y suplentes. En conclusión, todos los jugadores, independientemente de la posición de juego y la titularidad y/o suplencia muestran similares valores de proporcionalidad corporal y de pliegues cutáneos, mostrando en general altos valores de masa corporal y bajos niveles de tejido adiposo.The aim of the study was to provide descriptive information about the differences in proportionality of body mass and skinfold thickness between starters and reserves as playing position. They were selected in a non-probabilistic 04 professional clubs in the First Division of Professional Football Peruvian, considering 44 starters and 28 reserves. We assessed body mass, height, six skinfolds, body proportionality determined by the strategy of the Phantom. The results show that the proportionality of body mass and skinfold is similar, both generally and by playing position, with no significant differences between playing positions and titular or alternate players. In conclusion, all players regardless of playing position and title and/or substitution proportionality show similar values and skinfold body, showing generally high body mass values and low levels of fat.Peer Reviewe

    Minocycline rescues decrease in neurogenesis, increase in microglia cytokines and deficits in sensorimotor gating in an animal model of schizophrenia

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    Adult neurogenesis in the hippocampus is impaired in schizophrenic patients and in an animal model of schizophrenia. Amongst a plethora of regulators, the immune system has been shown repeatedly to strongly modulate neurogenesis under physiological and pathological conditions. It is well accepted, that schizophrenic patients have an aberrant peripheral immune status, which is also reflected in the animal model. The microglia as the intrinsic immune competent cells of the brain have recently come into focus as possible therapeutic targets in schizophrenia. We here used a maternal immune stimulation rodent model of schizophrenia in which polyinosinic-polycytidilic acid (Poly I:C) was injected into pregnant rats to mimic an anti-viral immune response. We identified microglia IL-1{beta} and TNF-{alpha} increase constituting the factors correlating best with decreases in net-neurogenesis and impairment in pre-pulse inhibition of a startle response in the Poly I:C model. Treatment with the antibiotic minocycline (3mg/kg/day) normalized microglial cytokine production in the hippocampus and rescued neurogenesis and behavior. We could also show that enhanced microglial TNF-{alpha} and IL-1{beta} production in the hippocampus was accompanied by a decrease in the pro-proliferative TNFR2 receptor expression on neuronal progenitor cells, which could be attenuated by minocycline. These findings strongly support the idea to use anti-inflammatory drugs to target microglia activation as an adjunctive therapy in schizophrenic patients

    A Cylindrical GEM Inner Tracker for the BESIII experiment at IHEP

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    The Beijing Electron Spectrometer III (BESIII) is a multipurpose detector that collects data provided by the collision in the Beijing Electron Positron Collider II (BEPCII), hosted at the Institute of High Energy Physics of Beijing. Since the beginning of its operation, BESIII has collected the world largest sample of J/{\psi} and {\psi}(2s). Due to the increase of the luminosity up to its nominal value of 10^33 cm-2 s-1 and aging effect, the MDC decreases its efficiency in the first layers up to 35% with respect to the value in 2014. Since BESIII has to take data up to 2022 with the chance to continue up to 2027, the Italian collaboration proposed to replace the inner part of the MDC with three independent layers of Cylindrical triple-GEM (CGEM). The CGEM-IT project will deploy several new features and innovation with respect the other current GEM based detector: the {\mu}TPC and analog readout, with time and charge measurements will allow to reach the 130 {\mu}m spatial resolution in 1 T magnetic field requested by the BESIII collaboration. In this proceeding, an update of the status of the project will be presented, with a particular focus on the results with planar and cylindrical prototypes with test beams data. These results are beyond the state of the art for GEM technology in magnetic field

    A model to explain angular distributions of J/ψJ/\psi and ψ(2S)\psi(2S) decays into ΛΛ\Lambda\overline{\Lambda} and Σ0Σ0\Sigma^0\overline{\Sigma}^0

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    BESIII data show a particular angular distribution for the decay of the J/ψJ/\psi and ψ(2S)\psi(2S) mesons into the hyperons ΛΛ\Lambda\overline{\Lambda} and Σ0Σ0\Sigma^0\overline{\Sigma}^0. More in details the angular distribution of the decay ψ(2S)Σ0Σ0\psi(2S) \to \Sigma^0\overline{\Sigma}^0 exhibits an opposite trend with respect to that of the other three channels: J/ψΛΛJ/\psi \to \Lambda\overline{\Lambda}, J/ψΣ0Σ0J/\psi \to \Sigma^0\overline{\Sigma}^0 and ψ(2S)ΛΛ\psi(2S) \to \Lambda\overline{\Lambda}. We define a model to explain the origin of this phenomenon.Comment: 6 pages, 7 figures, to be published in Chinese Physics

    Protein sequence and structure: Is one more fundamental than the other?

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    We argue that protein native state structures reside in a novel "phase" of matter which confers on proteins their many amazing characteristics. This phase arises from the common features of all globular proteins and is characterized by a sequence-independent free energy landscape with relatively few low energy minima with funnel-like character. The choice of a sequence that fits well into one of these predetermined structures facilitates rapid and cooperative folding. Our model calculations show that this novel phase facilitates the formation of an efficient route for sequence design starting from random peptides.Comment: 7 pages, 4 figures, to appear in J. Stat. Phy
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