1,084 research outputs found

    Boundary value problems for the stationary axisymmetric Einstein equations: a disk rotating around a black hole

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    We solve a class of boundary value problems for the stationary axisymmetric Einstein equations corresponding to a disk of dust rotating uniformly around a central black hole. The solutions are given explicitly in terms of theta functions on a family of hyperelliptic Riemann surfaces of genus 4. In the absence of a disk, they reduce to the Kerr black hole. In the absence of a black hole, they reduce to the Neugebauer-Meinel disk.Comment: 46 page

    Treatment responsiveness of replicated psychopathy profiles.

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    Theory and accumulating data suggest systematic heterogeneity among offenders with psychopathic traits. Several empirical investigations converge on the nature of subtypes, but little is known about differences in treatment responsivity. We have used the 4-facet model of the Psychopathy Checklist-Revised (PCL-R) to provide a framework for detecting subtypes. The present study used the full range of PCL-R scores in a sample of male violent offenders (N = 190) to replicate subtypes found in a partly overlapping sample by Neumann, Vitacco, and Mokros (2016), using Latent Profile Analysis (LPA), and subsequently to examine potential differences in treatment responsivity. Four subtypes emerged. Within the prototypical psychopathic group, the distinction between intent-to-treat and completers was crucial. Prototypical psychopathic offenders were significantly more likely to drop out, but completers appeared to proceed through the different phases of treatment in much the same way as the other groups. Clearly, more research is needed to elucidate treatment interfering mechanisms and their associated patient characteristics, particularly for the prototypical psychopathic group. Developing therapeutic strategies to improve treatment compliance is a necessary step in the development of specialized treatment programs for these difficult patients

    The flux pinning force and vortex phase diagram of single crystal FeTe0.60Se0.40

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    The flux pinning force density (Fp) of the single crystalline FeTe0.60Se0.40 superconductor has been calculated from the magnetization measurements. The normalized Fp versus h (=H/Hirr) curves are scaled using the Dew-Hughes formula to underline the pinning mechanism in the compound. The obtained values of pinning parameters p and q indicate the vortex pinning by the mixing of the surface and the point core pinning of the normal centers. The vortex phase diagram has also been drawn for the first time for the FeTe0.60Se0.40, which has very high values of critical current density Jc ~ 1.10(5) Amp/cm2 and the upper critical field Hc2(0) = 65T, with a reasonably high transition temperature Tc =14.5K.Comment: 12 pages, 4 figure

    Coherent quantum transport in narrow constrictions in the presence of a finite-range longitudinally polarized time-dependent field

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    We have studied the quantum transport in a narrow constriction acted upon by a finite-range longitudinally polarized time-dependent electric field. The electric field induces coherent inelastic scatterings which involve both intra-subband and inter-sideband transitions. Subsequently, the dc conductance G is found to exhibit suppressed features. These features are recognized as the quasi-bound-state (QBS) features which are associated with electrons making transitions to the vicinity of a subband bottom, of which the density of states is singular. Having valley-like instead of dip-like structures, these QBS features are different from the G characteristics for constrictions acted upon by a finite-range time-modulated potential. In addition, the subband bottoms in the time-dependent electric field region are shifted upward by an energy proportional to the square of the electric field and inversely proportional to the square of the frequency. This effective potential barrier is originated from the square of the vector potential and it leads to the interesting field-sensitive QBS features. An experimental set-up is proposed for the observation of these features.Comment: 8 pages, 4 figure

    Investigation of the ferromagnetic transition in the correlated 4d perovskites SrRu1x_{1-x}Rhx_xO3_3

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    The solid-solution SrRu1x_{1-x}Rhx_xO3_3 (0x10\le x \le1) is a variable-electron-configuration system forming in the nearly-cubic-perovskite basis, ranging from the ferromagnetic 4d4d^4 to the enhanced paramagnetic 4d5d^5. Polycrystalline single-phase samples were obtained over the whole composition range by a high-pressure-heating technique, followed by measurements of magnetic susceptibility, magnetization, specific heat, thermopower, and electrical resistivity. The ferromagnetic order in long range is gradually suppressed by the Rh substitution and vanishes at x0.6x \sim 0.6. The electronic term of specific-heat shows unusual behavior near the critical Rh concentration; the feature does not match even qualitatively with what was reported for the related perovskites (Sr,Ca)RuO3_3. Furthermore, another anomaly in the specific heat was observed at x0.9x \sim 0.9.Comment: Accepted for publication in PR

    Relation between anabolic androgenic steroid administration, aerobic physical training and glycogen supercompensation

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    Glycogen supercompensation is one of the adaptations induced by physical training. To potentiate this phenomenon, many athletes use supraphysiological doses of anabolic androgenic steroids (AAS). The purpose of this study was to evaluate the effects of nandrolone and aerobic physical exercise in rats, on body weight, plasmatic triglycerides levels, blood glucose and glycogen content. Male Wistar rats were randomly divided into 4 groups: Sedentary + vehicle (SV), Trained + vehicle (TV), Sedentary + AAS (SAAS) and Trained + AAS (TAAS) (n = 7-14/group). They received i.m. injections of nandrolone or vehicle for 9 weeks, and during the same period trained rats were submitted to aerobic exercise. Data were analyzed by two-way ANOVA and Tukey tests (p (SV: 0,2 ± 0,02 = SAAS: 0,21 ± 0,02 mg/100 mg)]. Blood glucose and soleus glycogen reserves remained unaltered. The use of supraphysiological doses of nandrolone did not potentiate any of the effects obtained in response to aerobic physical training.A supercompensação do glicogênio é uma das adaptações induzidas pelo treinamento físico. Visando potencializar este fenômeno, muitos atletas utilizam doses suprafisiológicas de esteróides anabólicos androgênicos (EAA). O objetivo deste estudo foi avaliar em ratos os efeitos da nandrolona e do exercício aeróbio sobre o peso corporal, triglicerídeos, glicose e reservas de glicogênio. Ratos Wistar machos foram aleatoriamente divididos em quatro grupos: sedentário + veículo (SV), treinado + veículo (TV), sedentário + EAA (SEAA) e treinado + EAA (TEAA, n = 7-14/grupo). Receberam injeção i.m. de nandrolona ou veículo durante nove semanas e durante o mesmo período os animais treinados foram submetidos a exercício aeróbio. Os dados foram analisados por ANOVA bifatorial e Tukey (p (SV: 0,2 ± 0,02 = SEAA: 0,21 ± 0,02mg/100mg)]. A glicemia e as reservas de glicogênio do sóleo permaneceram inalteradas. O uso de doses suprafisiológicas de nandrolona não potencializou nenhum dos efeitos obtidos em resposta ao treinamento aeróbio.La supercompensación de glucógeno es una de las adaptaciones inducidas por el entrenamiento físico. Visualizando potencializar este fenómeno, muchos atletas utilizan dosis suprafisiológicas de estos esteroides anabólicos androgénicos (EAA). El objetivo de este estudio fue el de evaluar en ratas los efectos de nandrolona y del ejercicio aeróbico sobre el peso corporal, los triglicéridos, la gluclosa y las reservas de glucógeno. Ratas Wistar machos fueron aleatóriamente divididas en 4 grupos: sedentarios + vehículo (SV), entrenada + vehículo (EV), sedentario + EAA (SEAA) y entrenada + EAA (EEAA, n = 7-14/grupo). Recibieron una inyección intramuscular de nandrolona en vehículo durante dos semanas y durante este mismo período los animales entrenados fueron sometidos a ejercicio aeróbico. Los datos fueron analizados usando las pruebas estadísticas ANOVA bifactorial y Tukey (p (SV: 0,2 ± 0,02 = SEAA: 0,21 ± 0,02mg/100mg)]. La glucemia y las reservas de glucógeno del sóleo permanecieron inalteradas. El uso de dosis superfisiológicas de nandrona no potencializaron ninguno de los efectos obtenidos en respuesta al entrenamiento aeróbico.187192Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Solving Problems of Practice in Education

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    The authors identify and discuss the many complexities involved in the translation of scientific information in the social sciences into forms usable for solving problems of practice in education. As a means of appropriately handling these complexities and the issues that arise, they prescribe a series of stages to be followed from the advent of a practitioner's situational problem to the design of a response to it. They assert that unless the process of translation is conducted with the prescribed level of understanding, appreciation, and rigor, the application of knowledge will be inaccurate.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68934/2/10.1177_107554708400600103.pd

    Wesson's IMT with a Weylian bulk

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    The foundations of Wesson's induced matter theory are analyzed. It is shown that the 5D empty bulk must be regarded rather as a Weylian space than as a Riemannian one.The framework of a Weyl-Dirac version of Wesson's theory is elaborated and discussed. The bulk possesses in addition to the metric tensor a Weylian connection vector as well Dirac's gauge function; there are no sources (mass, current) in the bulk. On the 4D brane one obtains a geometrically based unified theory of gravitation and electromagnetism with mass, currents and equations induced by the 5D bulkComment: 29 page
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