917 resultados para Bollinger, Lee C., 1946-
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La participación en carreras atléticas de calle ha aumentado; esto requiere detectar riesgos previos al esfuerzo físico. Objetivo. Identificar factores de riesgo del comportamiento y readiness de inscritos a una carrera. Método. Estudio transversal en aficionados de 18-64 años. Encuesta digital con módulos de IPAQ, PARQ+ y STEP. Muestreo aleatorio sistemático con n=510, para una inactividad física esperada de 35% (±5%). Se evaluó nivel de actividad física, consumo de alcohol (peligroso), de fruta, verdura, tabaco y sal, y readiness. Resultados. El cumplimiento de actividad física fue 97,4%; 2,4% consume nivel óptimo de fruta o verdura (diferencias por edad, sexo y estrato), 3,7% fuma y 44,1% consumo peligroso de alcohol. El 19,8% reportó PARQ+ positivo y 5,7% requiere supervisión. Hay diferencias por trabajo y estudio. Discusión. Los aficionados cumplen el nivel de actividad física; pero no de otros factores. Una estrategia de seguridad en el atletismo de calle es evaluar los factores de riesgo relacionados con el estilo de vida así como el readiness.
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La presente investigación tiene como objetivo explicar la influencia de la construcción de identidad cultural vietnamita en la Guerra de Independencia de Vietnam entre 1946 y 1954. Se argumenta que la construcción de identidad cultural justificó, promovió y legitimó la guerra de independencia como instrumento político ya que –en tanto proceso relacional– generó durante la colonización francesa prácticas de diferenciación fundamentadas en la reivindicación de los valores, tradiciones, costumbres, creencias y símbolos vietnamitas en torno a la resistencia. Ello propició una ruptura en las relaciones políticas imperantes, lo que condujo a la búsqueda de un nuevo orden social basado en la autodeterminación. Se utiliza una metodología de tipo cualitativa, fundamentada en el análisis documental e historiográfico.
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Transcripción del Decreto por el que se creaba el Instituto de Óptica del Consejo Superior de Investigaciones Científicas (C.S.I.C.), cuyas funciones, así como las secciones que tuviera, vendrían a ser las diversas ramas de la óptica: Física y Teórica, Óptica geométrica, Cálculo de sistemas, Fotometría, Óptica oftalmológica, Espectroscopia, así como estudios sobre Historia de la Óptica en España.
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Se resume lo acontecido en los actos de celebración de las séptima sesión plenaria del Consejo Superior de Investigaciones Científicas, que tuvo lugar entre el 27 y el 30 del mes de enero de 1947. Se abrieron los actos con una misa del Espíritu Santo, oficiada por el Obispo de Madrid-Alcalá en el nuevo templo del Consejo. Continuó el Ministro de Educación Nacional saludando a los miembros del Consejo con un discurso. Seguidamente, se impusieron las condecoraciones a los nuevos Consejeros de manos del Ministro de Educación, Sr. Ibáñez, que acompañó este acto con unas palabras de enaltecimiento a la labor de éstos. También hubo momento para un recuerdo emocionado para los consejeros fallecidos durante el año 1947. La sesión de clausura se celebró bajo la presidencia del Jefe del Estado, el día 31 de enero, con la presencia de personalidades tan importantes como el Presidente de las Cortes, el Cuerpo Diplomático y el Gobierno. El Director del Instituto 'José Celestino Mutis', pronunció una conferencia sobre 'Algunos aspectos interesantes de los alcaloides tropánicos'. A continuación el Ministro de Educación Nacional, pronunció un discurso en el que habló sobre la brillantez de la ciencia española; las Academias Españolas; ordenación de los Patronatos; el desarrollo científico en España; los caídos por España. Finalmente, el Jefe del Estado entregó los diplomas a los investigadores premiados en el curso 1946-1947, los premios de Ciencias y los de Letras.
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Premios Educación y Sociedad 1995. El ejemplar con R.111495 no tiene el cartel ni el ejemplar fotocopiado. Anexo Memoria en C- Innov.56
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Resumen basado en el de la publicaci??n
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Resumen basado en el de la publicaci??n
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Reaction of 2-(4'-R-phenylazo)-4-methylphenols (R = OCH3, CH3, H, Cl, and NO2) with [Ru(dmso)(4)Cl-2] affords a family of five ruthenium(III) complexes, containing a 2-(arylazo)phenolate ligand forming a six-membered chelate ring and a tetradentate ligand formed from two 2-(arylazo) phenols via an unusual C-C coupling linki.ng the two ortho carbons of the phenyl rings in the arylazo fragment. A similar reaction with 2-(2'-methylphenylazo)-4-methylphenol with [Ru(dmso)(4)Cl-2] has afforded a similar complex, in which one 2-(2'-methylphenylazo)-4-methylphenolate ligand is coordinated forming a six-membered chelate ring, and the other two ligands have undergone the C-C coupling reaction, and the coupled species is coordinated as a tetradentate ligand forming a five-membered N,O-chelate ring, a nine-membered N,N-chelate ring, and another five-membered chelate ring. Reaction of 2-(2',6'-dimethylphenylazo)-4-methylphenol with [Ru(dmso)(4)Cl-2] has afforded a complex in which two 2-(2',6'-dimethylphenylazo)-4-methylphenols are coordinated as bidentate N,O-donors forming five- and six-membered chelate rings, while the third one has undergone cleavage across the N=N bond, and the phenolate fragment, thus generated, remains coordinated to the metal center in the iminosemiquinonate form. Structures of four selected complexes have been determined by X-ray crystallography. The first six complexes are one-electron paramagnetic and show rhombic ESR spectra. The last complex is diamagnetic and shows characteristic H-1 NMR signals. All the complexes show intense charge-transfer transitions in the visible region and a Ru(III)-Ru(IV) oxidation on the positive side of SCE and a Ru(III)-Ru(II) reduction on the negative side.
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Activation of platelets by collagen is mediated through a tyrosine kinase-dependent pathway that is associated with phosphorylation of the Fc receptor gamma chain, the tyrosine kinase syk, and phospholipase C gamma2 (PLC gamma2). We recently described a collagen-related triple-helical peptide (CRP) with the sequence GCP*(GPP*)GCP*G (single letter amino acid code: P* = hydroxyproline; Morton et al, Biochem J306:337, 1995). The cross-linked peptide is a potent stimulus of platelet activation but, unlike collagen, does not support alpha2beta1-mediated, Mg2+-dependent adhesion, suggesting that its action is independent of the integrin alpha2beta1. This finding suggests the existence of a platelet receptor other than alpha2beta1 that underlies activation. In the present study, we show that CRP stimulates tyrosine phosphorylation of the same pattern of proteins in platelets as collagen, including syk and PLC gamma2. Protein tyrosine phosphorylation induced by CRP is not altered in the absence of Mg2+ or the presence of monoclonal antibodies (MoAbs) to the integrin alpha2beta1 (MoAb 6F1 and MoAb 13), conditions that prevent the interaction of collagen with the integrin. In contrast, phosphorylation of syk and PLC gamma2 by collagen is partially reduced by MoAb 6F1 and MoAb 13 or by removal of Mg2+. This may reflect a direct role of alpha2beta1 in collagen-induced signaling events or an indirect role in which the integrin facilitates the binding of collagen to its signaling receptor. The results show an alpha2beta1-independent pathway of platelet activation by CRP that involves phosphorylation of syk and PLC gamma2. This pathway appears to contribute to platelet activation by collagen.
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The surface drag force produced by trapped lee waves and upward propagating waves in non-hydrostatic stratified flow over a mountain ridge is explicitly calculated using linear theory for a two-layer atmosphere with piecewise-constant static stability and wind speed profiles. The behaviour of the drag normalized by its hydrostatic single-layer reference value is investigated as a function of the ratio of the Scorer parameters in the two layers l_2/l_1 and of the corresponding dimensionless interface height l_1 H, for selected values of the dimensionless ridge width l_1 a and ratio of wind speeds in the two layers. When l_2/l_1 → 1, the propagating wave drag approaches 1 in approximately hydrostatic conditions, and the trapped lee wave drag vanishes. As l_2/l_1 decreases, the propagating wave drag progressively displays an oscillatory behaviour with l_1 H, with maxima of increasing magnitude due to constructive interference of reflected waves in the lower layer. The trapped lee wave drag shows localized maxima associated with each resonant trapped lee wave mode, occurring for small l_2/l_1 and slightly higher values of l_1 H than the propagating wave drag maxima. As l1a decreases, i.e. the flow becomes more non-hydrostatic, the propagating wave drag decreases and the regions of non-zero trapped lee wave drag extend to higher l_2/l_1. These results are confirmed by numerical simulations for l_2/l_1 = 0.2. In parameter ranges of meteorological relevance, the trapped lee wave drag may have a magnitude comparable to that of propagating wave drag, and be larger than the reference single-layer drag. This may have implications for drag parametrization in global climate and weather-prediction models.
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The drag produced by 2D orographic gravity waves trapped at a temperature inversion and waves propagating in the stably stratified layer existing above are explicitly calculated using linear theory, for a two-layer atmosphere with neutral static stability near the surface, mimicking a well-mixed boundary layer. For realistic values of the flow parameters, trapped lee wave drag, which is given by a closed analytical expression, is comparable to propagating wave drag, especially in moderately to strongly non-hydrostatic conditions. In resonant flow, both drag components substantially exceed the single-layer hydrostatic drag estimate used in most parametrization schemes. Both drag components are optimally amplified for a relatively low-level inversion and Froude numbers Fr ≈ 1. While propagating wave drag is maximized for approximately hydrostatic flow, trapped lee wave drag is maximized for l_2 a = O(1) (where l_2 is the Scorer parameter in the stable layer and a is the mountain width). This roughly happens when the horizontal scale of trapped lee waves matches that of the mountain slope. The drag behavior as a function of Fr for l_2 H = 0.5 (where H is the inversion height) and different values of l2a shows good agreement with numerical simulations. Regions of parameter space with high trapped lee wave drag correlate reasonably well with those where lee wave rotors were found to occur in previous nonlinear numerical simulations including frictional effects. This suggests that trapped lee wave drag, besides giving a relevant contribution to low-level drag exerted on the atmosphere, may also be useful to diagnose lee rotor formation.
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The orographic gravity wave drag produced in flow over an axisymmetric mountain when both vertical wind shear and non-hydrostatic effects are important was calculated using a semi-analytical two-layer linear model, including unidirectional or directional constant wind shear in a layer near the surface, above which the wind is constant. The drag behaviour is determined by partial wave reflection at the shear discontinuity, wave absorption at critical levels (both of which exist in hydrostatic flow), and total wave reflection at levels where the waves become evanescent (an intrinsically non-hydrostatic effect), which produces resonant trapped lee wave modes. As a result of constructive or destructive wave interference, the drag oscillates with the thickness of the constant-shear layer and the Richardson number within it (Ri), generally decreasing at low Ri and when the flow is strongly non-hydrostatic. Critical level absorption, which increases with the angle spanned by the wind velocity in the constant-shear layer, shields the surface from reflected waves, keeping the drag closer to its hydrostatic limit. While, for the parameter range considered here, the drag seldom exceeds this limit, a substantial drag fraction may be produced by trapped lee waves, particularly when the flow is strongly non-hydrostatic, the lower layer is thick and Ri is relatively high. In directionally sheared flows with Ri = O(1), the drag may be misaligned with the surface wind in a direction opposite to the shear, a behaviour which is totally due to non-trapped waves. The trapped lee wave drag, whose reaction force on the atmosphere is felt at low levels, may therefore have a distinctly different direction from the drag associated with vertically propagating waves, which acts on the atmosphere at higher levels.
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We present a measurement of the fraction of inclusive W +jets events produced with net charm quantum number 11, denoted W + c-jet, in p collisions at root s = 1.96 TeV using approximately 1 fb(-1) of data collected by the do detector at the Fermilab Tevatron Collider. We identify the W +jets events via the leptonic W boson decays. Candidate W + c-jet events are selected by requiring a jet containing a muon in association with a reconstructed W boson and exploiting the charge correlation between this muon and W boson decay lepton to perform a nearly model-independent background subtraction. We measure the fraction of W + c-jet events in the inclusive W +jets sample for jet PT > 20 GeV and pseudorapidity |eta| < 2.5 to be 0.074 +/- 0.019(stat.) +/-(0.012)(0.014) (syst.), in agreement with theoretical predictions. The probability that background fluctuations could produce the observed fraction of W + c-jet events is estimated to be 2.5 x 10(-4), which corresponds to a 3.5 sigma statistical significance. Published by Elsevier B.V.