931 resultados para counter-hegemonic
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Three new ditopic imidazole ligands (2-4) were synthesized in high yields and characterized by various spectroscopic techniques. These ligands resulted in the formation of 3 + 6] self-assembled trinuclear barrels (5-7) in quantitative yields by stoichiometric combination of individual ligands and Pd(NO3)(2) in DMSO. All the three assemblies (5-7) were characterized by `H NMR and ESI-MS analysis, and subsequently, structures of the complexes 5 and 6 were confirmed by single-crystal X-ray diffraction studies. Structure analysis reveals the presence of NO3- counter anions in the intermolecular channels/pockets, which could potentially act as H-bonding sites between adsorbed water molecules within the channels. In fact, both the assemblies (5 and 6) showed water uptake (136.58, and 123.78 cm(3) g(-1), respectively) at ambient temperature under maximum allowable humidity. In addition, free aldehyde group present in the bridging ligand in complex 7 provides reactive site for postassembly modification. Herein, Knoevenagel condensation with Meldrum's acid was utilized under mild conditions by targeting aldehyde group appended in prefabricated complex 7 and transformed into a different complex (8) with altered functional group. Such postassembly functionalization enables incorporation of a new functional group without disrupting the integrity of the trifacial structure.
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CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) are exploited by mycobacteria to subvert the protective host immune responses. The Treg expansion in the periphery requires signaling by professional antigen presenting cells and in particularly dendritic cells (DC). However, precise molecular mechanisms by which mycobacteria instruct Treg expansion via DCs are not established. Here we demonstrate that mycobacteria-responsive sonic hedgehog (SHH) signaling in human DCs leads to programmed death ligand-1 (PD-L1) expression and cyclooxygenase (COX)-2-catalyzed prostaglandin E-2 (PGE(2)) that orchestrate mycobacterial infection-induced expansion of Tregs. While SHH-responsive transcription factor GLI1 directly arbitrated COX-2 transcription, specific microRNAs, miR-324-5p and miR-338-5p, which target PD-L1 were downregulated by SHH signaling. Further, counter-regulatory roles of SHH and NOTCH1 signaling during mycobacterial-infection of human DCs was also evident. Together, our results establish that Mycobacterium directs a fine-balance of host signaling pathways and molecular regulators in human DCs to expand Tregs that favour immune evasion of the pathogen.
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Here, we demonstrate a green and environment-friendly pyrolysis route for the synthesis of metal-rich sulphide embedded in an N-doped carbon (NC) framework in the absence of sulphide ions (S2-). The metal-chelate complex (tris(ethylenediamine) metal(II) sulfate) serves as a new and single source precursor for the synthesis of earth abundant and non-precious hybrid structures such as metal-rich sulphides Co9S8@NC and Ni3S2@ NC when M-II = Co2+ and Ni2+ and counter sulphate (SO42-) ions are the source of S. Both the hybrids show superior OER activity as compared to commercial RuO2.
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In this paper we report the design of high room temperature photoluminescence internal efficiency InGaN-based quantum well structures emitting in the near ultraviolet at 380 nm. To counter the effects of nonradiative recombination the quantum wells were designed to have a large indium fraction, high barriers, and a small quantum well thickness. To minimize the interwell and interbarrier thickness fluctuations we used Al0.2In0.005Ga0.795N barriers, where the inclusion of the small fraction of indium was found to lead to fewer structural defects and a reduction in the layer thickness fluctuations. This approach has led us to achieve, for an In0.08Ga0.92N/Al0.2In0.005Ga0.795N multiple quantum well structure with a well width of 1.5 nm, a photoluminescence internal efficiency of 67% for peak emission at 382 nm at room temperature. (c) 2007 American Institute of Physics.
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As part of a study of the wear of candidate heat exchanger tube materials for use in fluidized bed combustors, two similar laboratory-scale rigs have been built and characterized. Specimens of selected alloys are carried on counter-rotating rotors immersed in a fluidized bed, and are exposed to particle impact velocities of up to approximately 3 ms-1 at temperatures up to 1000°C. The performance of this design of apparatus has been investigated in detail. The effects of several experimental variables have been studied, including angle of particle impact, specimen speed, position of the rotor within the fluidized bed, duration of exposure, bed material particle size, degradation of the bed material, degree of fluidization of the bed, and size of specimen. In many cases the results obtained with steel specimens at elevated temperatures are similar to those observed with polymeric specimens at low temperatures.
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Resumen: Este artículo analiza la formación del sistema de partidos políticos chileno desde la teoría de clivajes o fisuras sociales. Esta teoría, ampliamente desarrollada en las ciencias sociales europeas, adoptó especial relevancia en el caso chileno y logró consenso sobre ciertos clivajes generativos del sistema de partidos –religioso y social–. Sin embargo, durante la década pasada, surgió la discusión sobre la existencia de otro clivaje: el autoritario, y si fue o no generativo de la actual configuración partidaria. En este contexto teórico, el presente trabajo se focaliza en dos objetivos: primero, presentar la configuración actual del sistema de partidos chileno y sus coaliciones, en base a los clivajes generativos que le dan forma, argumentando, especialmente, la retraducción actual del clivaje religioso –no hegemónico–, en el seno de la actual coalición política de gobierno, la Concertación; y segundo, en base a un enfoque cualitativo, pretende caracterizar empíricamente la retraducción de esta oposición clerical/anticlerical.
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The melt flow and temperature distribution in a 200 mm silicon Czochralski furnace with a cusp magnetic field was modeled and simulated by using a finite-volume based FLUTRAPP ( Fluid Flow and Transport Phenomena Program) code. The melt flow in the crucible was focused, which is a result of the competition of buoyancy, the centrifugal forces caused by the rotations of the crucible and crystal, the thermocapillary force on the free surfaces and the Lorentz force induced by the cusp magnetic field. The zonal method for radiative heat transfer was used in the growth chamber, which was confined by the crystal surface, melt surface, crucible, heat shield, and pull chamber. It was found that the cusp magnetic field could strength the dominant counter-rotating swirling flow cell in the crucible and reduce the flow oscillation and the pulling-rate fluctuation. The fluctuation of dopant and oxygen concentration in the growing crystal could thus be smoothed.
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Tanto en la primera como en la segunda parte del trabajo se argumenta sobre la planificación de investigaciones y sobre los métodos en el Psicoanálisis. En esta tercera parte se expone las distintas formas de la explicación y su aplicación en el Psicoanálisis, inmediatamente se discurre sobre el estatus de la predicción en la teoría psicoanalítica y la práctica investigativa. Se aborda ¨la profecía autocumplida¨ en la interpretación y amplificando desde otras disciplinas el problema de ¨cirularidad¨, su relación con la psicogénesis, la transferencia y la contratransferencia. Se contrastan las afirmaciones popperianas con las del fundador del Psicoanálisis.
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An economic expert working group (STECF/SGBRE-07-05) was convened in 2007 for evaluating the potential economic consequences of a Long-Term Management Plan for the northern hake. Analyzing all the scenarios proposed by biological assessment, they found that keeping the F in the status quo level was the best policy in terms of net present values for both yield and profits. This result is counter intuitive because it may indicate that effort costs do no affect the economic reference points. However, it is well accepted that the inclusion of costs affects negatively the economic reference points. In this paper, applying a dynamic agestructured model to the northern hake, we show that the optimal fishing mortality that maximizes the net present value of profits is lower than Fmax.
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The main objective of this paper is to analyse the value of information contained in prices of options on the IBEX 35 index at the Spanish Stock Exchange Market. The forward looking information is extracted using implied risk-neutral density functions estimated by a mixture of two-lognormals and three alternative risk-adjustments: the classic power and exponential utility functions and a habit-based specification that allows for a counter-cyclical variation of risk aversion. Our results show that at four-week horizon we can reject the hypothesis that between October 1996 and March 2000 the risk-neutral densities provide accurate predictions of the distributions of future realisations of the IBEX 35 index at a four-week horizon. When forecasting through risk-adjusted densities the performance of this period is statistically improved and we no longer reject that hypothesis. All risk-adjusted densities generate similar forecasting statistics. Then, at least for a horizon of four-weeks, the actual risk adjustment does not seem to be the issue. By contrast, at the one-week horizon risk-adjusted densities do not improve the forecasting ability of the risk-neutral counterparts.
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383 p. ; P.315-383: "Erauso Kateriñe" antzezlanaren edizioa dago.
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对超声速反向射流混合加热方案进行实验验证。实验结果表明:控制向燃烧室注入水雾的流量可以方便地调节燃烧室的温度和压力;用双路氢氧进气系统易于实现稳定的点火和燃烧。用热电偶测量混合前后的流场温度分布的初步结果表明,反向射流混合方案基本可行。
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[ES] Este trabajo propone una lectura de los seis primeros cuadernos del diario que Alejandra Pizarnik escribió a lo largo de toda su vida, desde los 18 años y hasta que murió a la edad de 36. El análisis de estos cuadernos, escritos entre 1954 y 1958, nos permite recorrer el itinerario que Alejandra Pizarnik realiza por la cuestión genérica, la cuestión nacional y la cuestión sexual. Desde su experiencia en cuanto sujeto, la escritura registra esta primera fase en la construcción del yo que Pizarnik desea para su diario. Esta fase, que se puede denominar etapa-derribo, está dominada por el desafío a las ideas del discurso hegemónico. Una vez haya resuelto este escollo en la construcción del yo de su diario, la escritura de Pizarnik no volverá sobre estos temas. Sin embargo, la búsqueda el “verdadero” yo se registra como proceso en el que a un movimiento de construcción del yo, le sigue un movimiento de destrucción de lo que las palabras han conformado, en secuencias en las que la apelación a la mentira de lo escrito o la desconfi anza en la capacidad del lenguaje para expresarlo, son la pauta de dicha escritura.
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A Knowledge Exchange workshop took place in March 2010 to bring together technical experts working in partner projects collecting usage statistics including PIRUS2, OAstatistik and SURFsure projects. Experts from other related projects (RePec and NeeO) were also involved. Following the workshop, experts came to the conclusion that it would be valuable for institutions in all four Knowledge Exchange partner countries as well as countries outside of KE, to have an agreed set of guidelines which could be used when collecting and comparing data on usage statistics. This work connects with work already planned in projects already funded in three of the countries. Together they have set up a set of guidelines which will be tested and refined by Autumn 2010. An element in these guidelines is an agreed robotlist. This list extends on the COUNTER list of robots which should be excluded when counting downloads.
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After nearly 15 years of research effort, High Temperature Superconductors (HTS) are finding a wide range of practical applications. A clear understanding of the factors controlling the current carrying capacity of these materials is a prerequisite to their successful technological development. The critical current density (Jc) in HTS is directly dependent on the structure and pinning of the Flux Line Lattice (FLL) in these materials. This thesis presents an investigation of the Jc anisotropy in HTS. The use of thin films grown on off c-axis (vicinal) substrates allowed the effect of current directions outside the cuprate planes to be studied. With this experimental geometry Berghuis, et al. (Phys. Rev. Lett. 79, 12, pg. 2332) observed a striking flux channelling effect in vicinal YBa2Cu3O7-δ (YBCO) films. By confirming, and extending, this observation, it is demonstrated that this is an intrinsic effect. The results obtained, appear to fit well with the predictions of a field angle dependent cross-over from a three dimensional rectilinear FLL to a kinked lattice of strings and pancakes. The pinning force density for movement of strings inside the cuprate planes is considerably less than that on vortex pancake elements. When the FLL is entirely string-like this reduced pinning leads to the observed channelling minima. It is observed that anti-phase boundaries enhance the Jc in vicinal YBCO films by strongly pinning vortex strings. The effect on the FLL structure cross-over of increasing anisotropy has been elucidated using de-oxygenated vicinal YBCO films. Intriguingly, the counter intuitive prediction that the range of applied field angle for which the kinked lattice is fully developed reduces with increasing anisotropy, appears to be confirmed. Although vortex channelling cannot be observed in c-axis YBCO films, the pinning force density for vortex string channelling has been extracted by observing string dragging. By studying the effect of rotating the applied field at a constant angle to the cuprate planes, it is possible to observe the cross-over into the string pancake regime in c-axis films. In the 3D region, the observed behaviour is well explained by the anisotropic Ginzburg-Landau model. Measurements were also made on thin films of the much more anisotropic Bi 2Sr2CaCu2O8+x material, grown on vicinal substrates. The absence of any flux channelling effect and clear adherence to the expected Kes-Law behaviour in the observed Jc characteristics does not provide evidence for the existence of the predicted ‘crossing lattice’ in Bi 2Sr2CaCu2O8+x .