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An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract Minor lymphocyte-stimulating (Mls) Ag are alloantigens that stimulate T cells expressing specific V beta regions. Recent studies have established that Mls Ag are examples of endogenous superantigens encoded by the products of endogenous mouse mammary tumor virus (MLV) genomes. In a mouse strain that expresses a given mammary tumor virus (Mls) Ag, reactive T cells expressing the corresponding V beta region are profoundly deficient, due at least in part to clonal deletion of the cells during their development. Expression of Mls and other endogenous superantigens, therefore, results in profound alterations in the ultimate repertoire of T cells in an animal. A role for endogenous superantigens in positive selection of T cells has not been previously established. Here we present evidence that expression of Mls-1a leads to a specific increase in the abundance of V beta 14+ T cells. Genetic studies indicate linkage of the effect to the Mls-1a gene. Neonatal tolerance studies argue against the possibility that the increase is due solely to the deletion of Mls-reactive V beta 14- T cells. The results are consistent with the Mls-1a product playing a role in the positive selection of V beta 14+ T cells.
Rooted in structural dynamics theory, three approximate procedures for estimating seismic demands for bridges crossing fault-rupture zones and deforming into their inelastic range are presented: modal pushover analysis (MPA), linear dynamic analysis, and linear static analysis. These procedures estimate the total seismic demand by superposing peak values of quasi-static and dynamic parts. The peak quasi-static demand in all three procedures is computed by nonlinear static analysis of the bridge subjected to peak values of all support displacements applied simultaneously. In the MPA and the linear dynamic analysis procedures, the peak dynamic demand is estimated by nonlinear static (or pushover) analysis and linear static analysis, respectively, for forces corresponding to the most-dominant mode. In the linear static analysis procedure, the peak dynamic demand is estimated by linear static analysis of the bridge due to lateral forces appropriate for bridges crossing fault-rupture zones. The three approximate procedures are shown to provide estimates of seismic demands that are accurate enough to be useful for practical applications. The linear static analysis procedure, which is much simpler than the other two approximate procedures, is recommended for practical analysis of “ordinary” bridges because it eliminates the need for mode shapes and vibration periods of the bridge.
El avance del Estado penal en Norteamérica. En este artículo se analiza la creciente importancia del sector carcelario en los Estados Unidos como elemento de una política que pretende criminalizar la pobreza y sus consecuencias, sentando así las bases de un nuevo régimen de salariado precario y desocializado como norma de ciudadanía y acabando con los tradicionales mecanismos de contención utilizados para mantener el orden racial. Se examinan tres modalidades del avance del Estado penal : 1) la instalación de un régimen de hiperinflación carcelaria permanente y generalizada, sin precedentes en una sociedad democrática : la población penitenciaria estadounidense se cuadruplica entre 1975 y 1995, ascendiendo a más de 1.700.000 detenidos (647 por 100.000 habitantes) en 1997, mientras la criminalidad se estanca, e incluso disminuye ; 2) la extension lateral de la « red penal » y el aumento correlativo de los medios indirectes de vigilancia y control de los pobres : en quince años, el número de norteamericanos bajo tutela penal aumenta de tres millones, llegando a 5.400.000 en 1995, es decir uno de cada veinte hombres y uno de cada diez negros (al mismo tiempo se vigila a 30 millones de personas por medio de « ficheros criminales » informatizados) ; 3) el aumento espectacular del presupuesto y el personal de las distintas administraciones penitenciarias (cuyas plantillas se duplican entre 1980 y 1993, haciendo de la administración penitenciaria el segundo empleador del país) en el momento mismo en que el Estado reduce el gasto público destinado a los grupos de población mas desfavorecidos. La deliberada atrofia del Estado social y la hipertrofia del Estado penal en los Estados Unidos, durante el último cuarto de siglo, se desarrollan como procesos concomitantes y complementarios que intervienen en la instalación de un nuevo gobierno de la miseria en cuyo seno, contrariamente a lo previsto por los analistas de la escena penal de la decada del 70, la prisión ocupa una posición central. En cuanto a los grupos relegados a los niveles inferiores del espacio social estadounidense, esto se traduce en una severa y puntillosa puesta bajo tutela que obedece a un paternalismo de Estado.
Drawing on archival materials and personal testimonies, I reconstruct the conditions under which Bourdieu came to receive the Gold Medal of the National Center for Scientific Research, France’s highest science prize, in 1993 as a signal case study of the existential predicament and institutional trappings of scholarly consecration. Bourdieu’s award speech and the ceremony at which he read it present a triple interest for the history and sociology of sociology. They illustrate how a shaping figure in the discipline personally experienced, reflexively viewed, and practically navigated the nexus of science, authority, and power. They mark 1993 as a pivot-year in Bourdieu’s intellectual evolution, leading to a new agenda foregrounding the state as paramount symbolic power, the alchemy of group formation, and the unfinished promise of democratic politics; and they help explain why he ventured more forthrightly into civic debate in the 1990s. Bourdieu’s ambivalent acceptance of the prize also illustrates his conception of the ‘Realpolitik of reason’ and put an emphatic end to the eclipse of Durkheim by restoring sociology to its rightful place at the scientific zenith in the country of its birth.
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Abstract Vinyl chloride, vinyl fluoride, and tetrafluoroethylene were polymerized in a radio frequency electric glow discharge. It was found that when compared with the unhalogenated simple hydrocarbons, the rates of polymer deposition are in the order vinyl chloride, acetylene, tetrafluoroethylene, vinyl fluoride, ethylene. This observation can be rationalized by considering the ease with which free radical and unsaturated species can be formed in the plasma. IR spectra show that the structures of plasma-polymerized vinyl chloride and vinyl fluoride are in many respects similar to the plasma-polymerized hydrocarbon. The spectrum of plasma-polymerized tetrafluoroethylene, however, does not resemble that of conventional polytetrafluoroethylene. Addition of dichlorodifluoromethane to the monomer stream dramatically increased the polymer deposition rate; the effect is more subdued for chloromethane and is negligible for tetrafluoromethane. Elemental analysis indicates that little of the added halogens is present in the resultant polymers. Thus the halogenated compounds appear to act as a gas phase catalyst for the plasma polymerization of hydrocarbons.
