266 research outputs found

    Purification and Preliminary Crystallographic Analysis of a New Lys49-PLA2 from B. Jararacussu

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    BjVIII is a new myotoxic Lys49-PLA2 isolated from Bothrops jararacussu venom that exhibits atypical effects on human platelet aggregation. To better understand the mode of action of BjVIII, crystallographic studies were initiated. Two crystal forms were obtained, both containing two molecules in the asymmetric unit (ASU). Synchrotron radiation diffraction data were collected to 2.0 Å resolution and 1.9 Å resolution for crystals belonging to the space group P212121 (a = 48.4 Å, b = 65.3 Å, c = 84.3 Å) and space group P3121 (a = b = 55.7 Å, c = 127.9 Å), respectively. Refinement is currently in progress and the refined structures are expected to shed light on the unusual platelet aggregation activity observed for BjVIII

    The Chemical Enrichment History of the Large Magellanic Cloud

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    Ca II triplet spectroscopy has been used to derive stellar metallicities for individual stars in four LMC fields situated at galactocentric distances of 3\arcdeg, 5\arcdeg, 6\arcdeg\@ and 8\arcdeg\@ to the north of the Bar. Observed metallicity distributions show a well defined peak, with a tail toward low metallicities. The mean metallicity remains constant until 6\arcdeg\@ ([Fe/H]\sim-0.5 dex), while for the outermost field, at 8\arcdeg, the mean metallicity is substantially lower than in the rest of the disk ([Fe/H]\sim-0.8 dex). The combination of spectroscopy with deep CCD photometry has allowed us to break the RGB age--metallicity degeneracy and compute the ages for the objects observed spectroscopically. The obtained age--metallicity relationships for our four fields are statistically indistinguishable. We conclude that the lower mean metallicity in the outermost field is a consequence of it having a lower fraction of intermediate-age stars, which are more metal-rich than the older stars. The disk age--metallicity relationship is similar to that for clusters. However, the lack of objects with ages between 3 and 10 Gyr is not observed in the field population. Finally, we used data from the literature to derive consistently the age--metallicity relationship of the bar. Simple chemical evolution models have been used to reproduce the observed age--metallicity relationships with the purpose of investigating which mechanism has participated in the evolution of the disk and bar. We find that while the disk age--metallicity relationship is well reproduced by close-box models or models with a small degree of outflow, that of the bar is only reproduced by models with combination of infall and outflow.Comment: 45 pages, 10 figures, accepted for publication in Astronomical Journa

    Purification and preliminary crystallographic analysis of a new Lys49-PLA2 from B-jararacussu

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    BjVIII is a new myotoxic Lys49-PLA2 isolated from Bothrops jararacussu venom that exhibits atypical effects on human platelet aggregation. To better understand the mode of action of BjVIII, crystallographic studies were initiated. Two crystal forms were obtained, both containing two molecules in the asymmetric unit (ASU). Synchrotron radiation diffraction data were collected to 2.0 angstrom resolution and 1.9 angstrom resolution for crystals belonging to the space group P2(1)2(1)2(1) (a = 48.4 angstrom, b = 65.3 angstrom, c = 84.3 angstrom) and space group P3(1)21 (a = b = 55.7 angstrom, c = 127.9 angstrom), respectively. Refinement is currently in progress and the refined structures are expected to shed light on the unusual platelet aggregation activity observed for BjVIII.9573675

    Purification And Preliminary Crystallographic Analysis Of A New Lys49-pla2 From B. Jararacussu

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    BjVIII is a new myotoxic Lys49-PLA2 isolated from Bothrops jararacussu venom that exhibits atypical effects on human platelet aggregation. To better understand the mode of action of BjVIII, crystallographic studies were initiated. Two crystal forms were obtained, both containing two molecules in the asymmetric unit (ASU). Synchrotron radiation diffraction data were collected to 2.0 Å resolution and 1.9 Å resolution for crystals belonging to the space group P2 12 12 1 (a = 48.4 Å, b = 65.3 Å, c = 84.3 Å) and space group P3 121 (a = b = 55.7 Å, c = 127.9 Å), respectively. 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Characterization of a new platelet aggregating factor from crotoxin Crotalus durissus cascavella venom (2006) Protein J, 25, pp. 183-192Schägger, H., von Jagow, G., Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa (1987) Anal Biochem, 166, pp. 368-379McPherson, A., Current approaches to macromolecular crystallization (1990) Eur J Biochem, 189, pp. 1-23Polikarpov, I., Oliva, G., Castellano, E.E., Garratt, R.C., Arruda, P., Leite, A., Craievich, A., The protein crystallography beamline at LNLS, the Brazilian National Synchrotron Light Source (1998) Nucl Instrum Methods Phys Res A, 405, pp. 159-164Polikarpov, I., Perles, L.A., de Oliveira, R.T., Oliva, G., Castellano, E.E., Garratt, R.C., Craievich, A.. Set-up and Experimental Parameters of the Protein Crystallography Beamline at the Brazilian National Synchrotron Laboratory (1998) J Synchrotron Radiat, 5, pp. 72-76Leslie, A.G., W.. 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Interfacial surface charge and free accessibility to the PLA2-active site-like region are essential requirements for the activity of Lys49 PLA2 homologues (2007) Toxicon, 49, pp. 378-387Toyama, M.H., Soares, A.M., Vieira, C.A., Novello, J.C., Oliveira, B., Giglio, J.R., Marangoni, S.. Amino acid sequence of piratoxin-I, a myotoxin from Bothrops pirajai snake venom, and its biological activity after alkylation with p-bromophenacyl bromide (1998) J Protein Chem, 17, pp. 713-718Barbosa, P. S. F.Martins, A. M. C.Alves, R. S.Amora, D. N.Martins, R. D.Toyama, M. H.Havt, A.Nascimento, N. R. F.Rocha, V. L. C.Menezes, D. B.Fonteles, M. C.Monteiro, H. S. A. . The role of indomethacin and tezosentan on renal effects induced by Bothrops moojeni Lys49 myotoxin I. Toxicon 2006, 47, 831-837Kramer, R.M., Roberts, E.F., Manetta, J.V., Hyslop, P.A., Jakubowski, J., A.. 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    Neurocognition and functional outcome in patients with psychotic, non-psychotic bipolar I disorder, and schizophrenia. A five-year follow-up

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    Bipolar disorder (BD) and schizophrenia (SZ) are characterized by neurocognitive and functional deficits with marked heterogeneity. It has been suggested that BD with a history of psychotic symptoms (BD-P) could constitute a phenotypically homogeneous subtype characterized by greater neurocognitive and functional impairments, or by a distinct trajectory of such deficits. The aim of this study was to compare the neurocognitive and functional course of euthymic BD-P, euthymic BD patients without a history of psychosis (BD-NP), stabilized patients with schizophrenia and healthy subjects, during a five-year follow-up

    A new search for planet transits in NGC 6791

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    Context. Searching for planets in open clusters allows us to study the effects of dynamical environment on planet formation and evolution. Aims. Considering the strong dependence of planet frequency on stellar metallicity, we studied the metal rich old open cluster NGC 6791 and searched for close-in planets using the transit technique. Methods. A ten-night observational campaign was performed using the Canada-France-Hawaii Telescope (3.6m), the San Pedro M\'artir telescope (2.1m), and the Loiano telescope (1.5m). To increase the transit detection probability we also made use of the Bruntt et al. (2003) eight-nights observational campaign. Adequate photometric precision for the detection of planetary transits was achieved. Results. Should the frequency and properties of close-in planets in NGC 6791 be similar to those orbiting field stars of similar metallicity, then detailed simulations foresee the presence of 2-3 transiting planets. Instead, we do not confirm the transit candidates proposed by Bruntt et al. (2003). The probability that the null detection is simply due to chance coincidence is estimated to be 3%-10%, depending on the metallicity assumed for the cluster. Conclusions. Possible explanations of the null-detection of transits include: (i) a lower frequency of close-in planets in star clusters; (ii) a smaller planetary radius for planets orbiting super metal rich stars; or (iii) limitations in the basic assumptions. More extensive photometry with 3-4m class telescopes is required to allow conclusive inferences about the frequency of planets in NGC 6791.Comment: 23 pages, 23 figures, A&A accepte

    Plasma Assisted Oblique Angle Deposition of Transparent and Conductive in- Plane Anisotropic ITO Thin Films

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    Oblique angle deposition (OAD) is a powerful technique for the fabrication of porous nanostructured oxide thin films. OAD films typically present a columnar tilted nanostructure due to geometrical shadowing effects during the thin film growth. In this work, we study the fabrication of transparent and conducting indium tin oxide films (ITO) by OAD assisted by a microwave ECR plasma. The objective of assisting the deposition with a plasma discharge is to modify the growth mechanism of the OAD process introducing additional parameters to control the columnar microstructure, composition, porosity of the films. The results indicate the OAD ITO deposition assisted by the plasma discharge is a very effective process to develop in-plane structural anisotropy in the ITO nanocolumnar films what determines their electrical properties.España MINECO-AEI MAT2016-79866-R, MAT2013-40852-R, MAT2013-42900-PEspaña MINECO-CSIC 201560E055, IJCI-2014-21226

    Enhanced stability of perovskite solar cells incorporating dopant-free Crystalline spiro-OMeTAD layers by vacuum sublimation

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    The main handicap still hindering the eventual exploitation of organometal halide perovskite-based solar cells is their poor stability under prolonged illumination, ambient conditions, and increased temperatures. This article shows for the first time the vacuum processing of the most widely used solid-state hole conductor (SSHC), i.e., the Spiro-OMeTAD [2,2′,7,7′-tetrakis (N,N-di-p-methoxyphenyl-amine) 9,9′-spirobifluorene], and how its dopant-free crystalline formation unprecedently improves perovskite solar cell (PSC) stability under continuous illumination by about two orders of magnitude with respect to the solution-processed reference and after annealing in air up to 200 °C. It is demonstrated that the control over the temperature of the samples during the vacuum deposition enhances the crystallinity of the SSHC, obtaining a preferential orientation along the π–π stacking direction. These results may represent a milestone toward the full vacuum processing of hybrid organic halide PSCs as well as light-emitting diodes, with promising impacts on the development of durable devices. The microstructure, purity, and crystallinity of the vacuum sublimated Spiro-OMeTAD layers are fully elucidated by applying an unparalleled set of complementary characterization techniques, including scanning electron microscopy, X-ray diffraction, grazing-incidence small-angle X-ray scattering and grazing-incidence wide-angle X-ray scattering, X-ray photoelectron spectroscopy, and Rutherford backscattering spectroscopy.The authors thank the “Agencia Estatal de Investigación”, “Consejería de Economía y Conocimiento de la Junta de Andalucía” (US‐1263142), “Ministerio de Economía y Competitividad” (MAT2016‐79866‐R, MAT2013‐42900‐P, FPA2016‐77689‐C2‐1‐R, and MAT2016‐76892‐C3‐2‐R) and the European Union (EU) through cohesion fund and FEDER 2014‐2020 programs for financial support. J.R.S.‐V. and A.B. acknowledge the EU project PlasmaPerovSol and funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska‐Curie grant agreement ID 661480. J.R.S.‐V‐ and M.C.L.‐S. thank the University of Seville through the VI “Plan Propio de Investigación y Transferencia de la US” (VI PPIT‐US). This research has received funding from the EU‐H2020 research and innovation programme under Grant Agreement No. 654360 having benefitted from the access provided by Technische Universität Graz at Elettra—TUG in Trieste (IT) within the framework on the NFFA (Nanoscience Foundries & Fine Analysis) Europe Transnational Access Activity. F.J.A. and J.R.S.‐V. acknowledge the “Juan de la Cierva” and “Ramon y Cajal” national programs, respectively

    Evaluation of turbulent dissipation rate retrievals from Doppler Cloud Radar

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    Turbulent dissipation rate retrievals from cloud radar Doppler velocity measurements are evaluated using independent, in situ observations in Arctic stratocumulus clouds. In situ validation data sets of dissipation rate are derived using sonic anemometer measurements from a tethered balloon and high frequency pressure variation observations from a research aircraft, both flown in proximity to stationary, ground-based radars. Modest biases are found among the data sets in particularly low- or high-turbulence regimes, but in general the radar-retrieved values correspond well with the in situ measurements. Root mean square differences are typically a factor of 4-6 relative to any given magnitude of dissipation rate. These differences are no larger than those found when comparing dissipation rates computed from tetheredballoon and meteorological tower-mounted sonic anemometer measurements made at spatial distances of a few hundred meters. Temporal lag analyses suggest that approximately half of the observed differences are due to spatial sampling considerations, such that the anticipated radar-based retrieval uncertainty is on the order of a factor of 2-3. Moreover, radar retrievals are clearly able to capture the vertical dissipation rate structure observed by the in situ sensors, while offering substantially more information on the time variability of turbulence profiles. Together these evaluations indicate that radar-based retrievals can, at a minimum, be used to determine the vertical structure of turbulence in Arctic stratocumulus clouds

    Characterization of Patients with Chronic Diseases and Complex Care Needs: A New High-Risk Emergent Population

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    Background: To analyze the prevalence and main epidemiological, clinical and outcome features of in-Patients with Complex Chronic conditions (PCC) in internal medicine areas, using a pragmatic working definition. Methods: Prospective study in 17 centers from Spain, with 97 in-hospital, monthly prevalence cuts. A PCC was considered when criteria of polypathological patient (two or more major chronic diseases) were met, or when a patient suffered one major chronic disease plus one or more of nine predefined complexity criteria like socio-familial risk, alcoholism or malnutrition among others (PCC without polypathology). A complete set of baseline features as well as 12-months survival were collected. Then, we compared clinical, outcome variables, and PROFUND index accuracy between polypathological patients and PCC without polypathology. Results: The global prevalence of PCC was 61% (40% of them were polypathological patients, and 21% PCC withouth polypathology) out of the 2178 evaluated patients. Their median age was 82 (59.5% men), suffered 2.3 ± 1.1 major diseases (heart diseases (70.5%), neurologic (41.5%), renal (36%), and lung diseases (26%)), 5.5 ± 2.5 other chronic conditions, met 2.5 ± 1.5 complexity criteria, and presented functional decline (Barthel index 55 (25-90)). Compared to polypathological patients, the subgroup of PCC without polypathology were younger, with a different pattern of major diseases and comorbidities, a better functional status, and lower 12-months mortality rates ((36.2% vs 46.8%; p = .003; OR 0.7(0.48-0.86). The PROFUND index obtained adequate calibration and discrimination power (AUC-ROC 0.67 (0.63-0.69)) in predicting 12-month mortality of PCC. Conclusion: Patients with complex chronic conditions are highly prevalent in internal medicine areas; their clinical pattern has changed in parallel to socio-epidemiological modifications, but their death-risk is still adequately predicted by PROFUND index
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