164 research outputs found

    Megaphylogenetic Specimen-Level Approaches to the Carex (Cyperaceae) Phylogeny Using ITS, ETS, and matK Sequences: Implications for Classification

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    We present the first large-scale phylogenetic hypothesis for the genus Carex based on 996 of the 1983 accepted species (50.23%). We used a supermatrix approach using three DNA regions: ETS, ITS and matK. Every concatenated sequence was derived from a single specimen. The topology of our phylogenetic reconstruction largely agreed with previous studies. We also gained new insights into the early divergence structure of the two largest clades, core Carex and Vignea clades, challenging some previous evolutionary hypotheses about inflorescence structure. Most sections were recovered as non-monophyletic. Homoplasy of characters traditionally selected as relevant for classification, historical misunderstanding of how morphology varies across Carex, and regional rather than global views of Carex diversity seem to be the main reasons for the high levels of polyphyly and paraphyly in the current infrageneric classification

    Geología, mineralogía y estructura de la mina Acazoque (Pb-Ag-Zn), Puna salteña

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    Mina Acazoque, ubicada en la Puna salteña (24° S), corresponde a un depósito epitermal de baja sulfuración relacionada con la actividad magmática miocena. Es un yacimiento de Pb-Ag-Zn emplazado en rocas graníticas correspondientes al Complejo eruptivo Oire que posee una corrida de aproximadamente 500 m y potencia media de 0,60 m. La mineralización primaria está constituida por galena, calcopirita, pirita, tetraedrita y estannita en ganga de fluorita, baritina, adularia, calcita y cuarzo. La mineralización secundaria está representada por cerusita, covelina, calcosina, azurita, malaquita y limonita. La veta tiene un contacto neto con la roca de caja y muestra textura maciza variando a brechosa. Microsonda electrónica de barrido fue usada en este estudio con el fin de determinar la química de los minerales más abundantes en la veta. La composición química de los minerales son: adularia: K 0.92 Al 0.89 Si 3.09 O 8, baritina: Ba 0.97 Sr 0.03 SO4, calcita: Ca 1.87 Mn 0.01 (CO3)2, cerusita: Pb 1.47 Ca 0.01 CO3, galena: Pb 0.97 S1. El control de la mineralización es estructural, emplazándose en planos de falla de rumbo N 50Oº e inclinaciones de 70º al SO con desplazamiento relativo de bloques oblicuo (normal-dextral). Nuestros datos indican que el emplazamiento de la mineralización fue sin-deformacional, relacionado con la evolución de la caldera del cerro Aguas Calientes (10,3 Ma). El campo de esfuerzos local determinado resulta consistente con el regional.Fil: Salado Paz, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Petrinovic, Ivan Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Avila, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Brod, J. A.. Universidade Federal de Goiás; Brasi

    Dead-time optimization to increase secure distance range in prepare and measure quantum key distribution protocols

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    Afterpulsing is a factor limiting the distance over which discrete-variable quantum key distribution systems are secure, and a common feature in single-photon detectors. The relevance of this phenomenon stems from its stochastic, self-interacting nature and the fact that its rate rises with the number of avalanche events, which increases the quantum bit error rate. Here we introduce an effective analytic model, including dead-time and afterpulsing corrections, where afterpulsing correction depends on dead-time value. This model is useful to evaluate the performance of prepare and measure quantum key distribution protocols (standard and decoy versions) that use gated single photon detectors. The model provides an expression to numerically optimize the secret key rate over the full distance range for secure communication, enabling in this way the calculation of quantum bit error rate and secure key rate. In the conventional procedure, the dead-time value is fixed regardless of distance, limiting the distance range of the channel due to remaining afterpulsing effects, which are more relevant at higher operating frequencies. Here we demonstrate that optimizing the dead-time values increases the distance range of the channel to share secret keys.Comment: 13 pages, 9 figure

    Raman spectra and vibrational analysis of CsPbI3: a fast and reliable technique to identify lead halide perovskite polymorphs

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    A major issue in the development of Lead halide perovskites is the assessment of the crystal structure of the samples, due to their typically limited time-stability, and the understanding of the role of external factors that can induce a crystal phase transformation (such as humidity, intense light flux, temperature, etc.). In this perspective, it is of utmost importance to have at disposal a fast and reliable experimental tool able to give an immediate indication of the polymorph of the sample with the possibility to integrate in-situ measurements for constant monitoring. In this paper we propose Raman spectroscopy as the ideal technique to solve this problem. The vibrational analysis of CsPbI3 in the α-phase and δ-phase and of the Cs4PbI6 secondary phase is reported and all the vibrational modes are assigned by comparing experimental spectra of the phases to Raman modes calculated within the DFT framework. Finally, the mechanism of laser induced phase degradation was studied using in-situ Raman measurements providing new insights on the secondary phase generated during the process

    Terneros de raza retinta en cebadero: análisis individual y por lotes

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    La raza Retinta dispone de un censo aproximado de 200.000 reproductoras de las cuales más de un 10% están inscritas en el Libro Genealógico de la raza. Representa el 5,3% del bovino español y el 14,5% del autóctono. En este trabajo se ha controlado el cebo de 373 terneros machos retintos puros procedentes de la ganadería del Centro Experimental Agrícola Ganadero de Jerez de la Frontera de la Excma. Diputación de Cádiz. Los animales se controlaron desde el destete hasta que fueron sacrificados, pesándolos con periodicidad mensual, con un total de 1984 pesadas, de las cuales 373 corresponden a la pesada de entrada en cebadero, 1.238 han sido pesadas durante el período de cebo y 373 pesadas al sacrificio. La duración media del cebo fue 158,5±2,8 días (cv 34,2%). El período medio de aclimatación al cebo tuvo una duración media de 32,6±Q,9 días, iniciándose el cebo los terneros con una edad media de 226,5±1,5 días y un peso de 27 1,3±2,6 kg. El peso promedio al sacrificio en todo el período analizado (l a años) fue de 518,0±3,9 kg (con un cv del 14,6%). El 70% de los animales se sacrificaron con un peso comprendido entre los 450 y 600 Kg resultando una ganancia media diaria (GMD) global de 1,58±O,012 kg/día (cv del 14,1 %) con un valor mínimo de 0,76 kg/día y un máximo de 2,27. Se puede resaltar que el 14% de los terneros presentaron una GMD superior a los 2 Kg/día. Se obtuvo un índice de transformación global (IT) de 5,29 y un consumo medio diario por animal (CMD) de 8,77 kg. Los valores medios de los lotes cebados en los dos últimos años presentaron un peso al sacrificio de 575,2 kg para una duración del cebo de 175,9.±4,2 días y una GMD de 1,6 Kg/día. La media del IT fue de 5,18 y del CMD de 8,98 Kg, con unos c.v. del 5,93% y del 5,23% respectivamente. Se han estudiado los factores que influyen sobre las variables peso de sacrificio y GMD en cebo mediante un ANOVA multifa ctorial. La paridera y la época de inicio del cebo han sido algunos de los factores de influencia

    Three-dimensional growth as multicellular spheroid activates the proangiogenic phenotype of colorectal carcinoma cells via LFA-1-dependent VEGF: implications on hepatic micrometastasis

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    Background: The recruitment of vascular stromal and endothelial cells is an early event occurring during cancer cell growth at premetastatic niches, but how the microenvironment created by the initial three-dimensional (3D) growth of cancer cells affects their angiogenesis-stimulating potential is unclear. Methods: The proangiogenic profile of CT26 murine colorectal carcinoma cells was studied in seven-day cultured 3D-spheroids of <300 mu m in diameter, produced by the hanging-drop method to mimic the microenvironment of avascular micrometastases prior to hypoxia occurrence. Results: Spheroid-derived CT26 cells increased vascular endothelial growth factor (VEGF) secretion by 70%, which in turn increased the in vitro migration of primary cultured hepatic sinusoidal endothelium (HSE) cells by 2-fold. More importantly, spheroid-derived CT26 cells increased lymphocyte function associated antigen (LFA)-1-expressing cell fraction by 3-fold; and soluble intercellular adhesion molecule (ICAM)-1, given to spheroid-cultured CT26 cells, further increased VEGF secretion by 90%, via cyclooxygenase (COX)-2-dependent mechanism. Consistent with these findings, CT26 cancer cells significantly increased LFA-1 expression in non-hypoxic avascular micrometastases at their earliest inception within hepatic lobules in vivo; and angiogenesis also markedly increased in both subcutaneous tumors and hepatic metastases produced by spheroid-derived CT26 cells. Conclusion: 3D-growth per se enriched the proangiogenic phenotype of cancer cells growing as multicellular spheroids or as subclinical hepatic micrometastases. The contribution of integrin LFA-1 to VEGF secretion via COX-2 was a micro environmental-related mechanism leading to the pro-angiogenic activation of soluble ICAM-1-activated colorectal carcinoma cells. This mechanism may represent a new target for specific therapeutic strategies designed to block colorectal cancer cell growth at a subclinical micrometastatic stage within the liver.Supported in part by Pharmakine S. L., and by grants from the CICYT of the Spanish government (SAF2006-09341), and the Basque Country Government (IT-487-07

    Prognostic classification for malignant tumors of the parotid gland

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    AbstractObjectiveThe histological classification of the World Health Organization (WHO), along with improved imaging studies, provide relevant information for the management of parotid carcinomas. However, the prognosis depends on factors other than histology and tumor extension. This article evaluates the usefulness of a prognostic classification of parotid cancers, including these factors in patients in a hospital area.MethodsA follow-up was conducted on 19 patients with parotid carcinomas, excluding lymphoid tumors or intra-parotid metastases, between 1998 and 2012. The prognostic index was obtained from the formulas proposed by Vander Poorten, with factors including age, tumor size, lymph node involvement, skin invasion, facial nerve involvement, perineural growth and margins of resection, before surgery (PS1) and after (PS2). Overall survival was related to 5 years for each patient based on their inclusion in any of the 4 risk groups defined.ResultsRisk stratification based on the results Vander Poorten PS2 was distributed into Risk Groups (GR) 1 (3 patients, 15.7%), 2 (5 patients, 26.3%), 3 (1 patient, 5.8%) and 4 (10 patients, 52.2%). The 6 patients who died during follow-up belonged to GR4. Only one of the 4 patients belonging to GR4 has exceeded the 5-year survival up to the current time.The comparison of the values that relate the pretreatment (PS1) and after treatment (PS2) results showed overall survival in patients with PS1<4.5 and PS2<4.9, whereas mortality was greater with indices of PS1>6.5 and PS2>7.7.ConclusionsVander Poorten index can be applied in hospital areas with small numbers of parotid carcinomas. It enables a more accurate prognosis for individual patients

    Manejo con control de temperatura en los cuidados posparada cardiaca: documento de expertos

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    Targeted temperature management (TTM) through induced hypothermia (between 32-36 C) is currently regarded as a first-line treatment during the management of post-cardiac arrest patients admitted to the Intensive Care Unit (ICU). The aim of TTM is to afford neuroprotection and reduce secondary neurological damage caused by anoxia. Despite the large body of evidence on its benefits, the TTM is still little used in Spain. There are controversial issues referred to its implementation, such as the optimal target body temperature, timing, duration and the rewarming process. The present study reviews the best available scientific evidence and the current recommendations contained in the international guidelines. In addition, the study focuses on the practical implementation of TTM in post-cardiac arrest patients in general and cardiological ICUs, with a discussion of the implementation strategies, protocols, management of complications and assessment of the neurological prognosis. oActualmente, el control estricto de temperatura mediante hipotermia inducida (entre 32 y 36 oC) se considera un tratamiento de primera línea en el manejo de pacientes con parada cardiaca recuperada que ingresan en Unidades de Cuidados Intensivos. Su objetivo es disminuir el da˜no neurológico secundario a anoxia cerebral. Aunque existen múltiples evidencias sobre sus beneficios, el empleo de esta técnica en nuestro país es pobre y todavía existen temas controvertidos como temperatura óptima, velocidad de instauración, duración y proceso de calentamiento. El objetivo de este trabajo es desarrollar la evidencia científica actual y las recomendaciones de las principales guías internacionales. El enfoque de este documento se centra también en aplicación práctica del control estricto de la temperatura en la parada cardiaca recuperada en nuestras Unidades de Cuidados Intensivos Generales o Cardiológicas, principalmente en los métodos de aplicación, protocolos, manejo de las complicaciones y elaboración del pronóstico neurológic
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