692 research outputs found
Personality Characteristics of Alcoholics
In recent years there has been an increased scientific interest in the obsessive and compulsive use of ethyl aleohol -alcoholism. Concomitant with this increased interest in the alcoholic, there has been a decreasing tendency to regard alcoholism as moral turpitude, but rather to refer to it as a disease and to seek its genesis within the dynamics of the interrelated relationships of the emotional, mental, and physiological make-up of the individual. It is generally recognised that the personality is the framework upon which alcohol plays Its role to produce the alcoholic
Tension Perturbations of Black Brane Spacetimes
We consider black-brane spacetimes that have at least one spatial translation
Killing field that is tangent to the brane. A new parameter, the tension of a
spacetime, is defined. The tension parameter is associated with spatial
translations in much the same way that the ADM mass is associated with the time
translation Killing field. In this work, we explore the implications of the
spatial translation symmetry for small perturbations around a background black
brane. For static charged black branes we derive a law which relates the
tension perturbation to the surface gravity times the change in the the horizon
area, plus terms that involve variations in the charges and currents. We find
that as a black brane evaporates the tension decreases. We also give a simple
derivation of a first law for black brane spacetimes. These constructions hold
when the background stress-energy is governed by a Hamiltonian, and the results
include arbitrary perturbative stress-energy sources.Comment: 21 pages, o figures, harvma
On the existence of Killing vector fields
In covariant metric theories of coupled gravity-matter systems the necessary
and sufficient conditions ensuring the existence of a Killing vector field are
investigated. It is shown that the symmetries of initial data sets are
preserved by the evolution of hyperbolic systems.Comment: 9 pages, no figure, to appear in Class. Quant. Gra
Optical Link of the Atlas Pixel Detector
The on-detector optical link of the ATLAS pixel detector contains
radiation-hard receiver chips to decode bi-phase marked signals received on PIN
arrays and data transmitter chips to drive VCSEL arrays. The components are
mounted on hybrid boards (opto-boards). We present results from the irradiation
studies with 24 GeV protons up to 32 Mrad (1.2 x 10^15 p/cm^2) and the
experience from the production.Comment: 9th ICATPP Conference, Como, Ital
Structured matrices, continued fractions, and root localization of polynomials
We give a detailed account of various connections between several classes of
objects: Hankel, Hurwitz, Toeplitz, Vandermonde and other structured matrices,
Stietjes and Jacobi-type continued fractions, Cauchy indices, moment problems,
total positivity, and root localization of univariate polynomials. Along with a
survey of many classical facts, we provide a number of new results.Comment: 79 pages; new material added to the Introductio
Stratification of the orbit space in gauge theories. The role of nongeneric strata
Gauge theory is a theory with constraints and, for that reason, the space of
physical states is not a manifold but a stratified space (orbifold) with
singularities. The classification of strata for smooth (and generalized)
connections is reviewed as well as the formulation of the physical space as the
zero set of a momentum map. Several important features of nongeneric strata are
discussed and new results are presented suggesting an important role for these
strata as concentrators of the measure in ground state functionals and as a
source of multiple structures in low-lying excitations.Comment: 22 pages Latex, 1 figur
Effects of tea from Turnera ulmifolia L. on mouse gastric mucosa support the Turneraceae as a new source of antiulcerogenic drugs
Turnera ulmifolia is a plant belonging to the family Turneraceae, popularly known in Brazil as chanana. This species is distributed from Guyana to southern Brazil where it is considered a weed. The plant occurs in tropical rain forest, fields, and gardens. Chanana tea is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric dysfunction including gastric and duodenal ulcers. In this study, the ability of a lyophilized infusion, as an aqueous fraction (AqF) of the aerial parts of T. ulmifolia, was investigated for its ability to prevent ulceration of the gastric and duodenal mucosa was examined in mice and rats, respectively. The AqF significantly reduced the formation of lesions associated with HCl/ethanol administration by 39% and 46%, respectively, at doses of 500 mg/kg and 1000 mg/kg, p.o. The AqF also significantly reduced the incidence of gastric lesions induced by a combination of indomethacin and bethanechol by 58% and 72% at doses of 500 mg/kg and 1000 mg/kg, respectively. In stress-induced gastric ulcer, the inhibition by the AqF was 48%, 57%, and 58% at doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg, respectively (p<0.05). A pyloric ligature experiment showed that the highest dose of the AqF significantly affected the gastric juice parameters by increasing the pH from 2.5 (control) to 5.3 and decreasing the acid output from 11.3 (control) to 3.7 mEq/ml/4 h. The AqF had no significant effect on duodenal ulcers induced by cysteamine. Preliminary phytochemical screening confirmed that flavonoids were the major constituents of the AqF of T. ulmifolia. These results indicate that this extract has a significant antiulcerogenic effect, as popularly believed.25448749
Supersonic strain front driven by a dense electron-hole plasma
We study coherent strain in (001) Ge generated by an ultrafast
laser-initiated high density electron-hole plasma. The resultant coherent pulse
is probed by time-resolved x-ray diffraction through changes in the anomalous
transmission. The acoustic pulse front is driven by ambipolar diffusion of the
electron-hole plasma and propagates into the crystal at supersonic speeds.
Simulations of the strain including electron-phonon coupling, modified by
carrier diffusion and Auger recombination, are in good agreement with the
observed dynamics.Comment: 4 pages, 6 figure
Proof of the Thin Sandwich Conjecture
We prove that the Thin Sandwich Conjecture in general relativity is valid,
provided that the data satisfy certain geometric
conditions. These conditions define an open set in the class of possible data,
but are not generically satisfied. The implications for the ``superspace''
picture of the Einstein evolution equations are discussed.Comment: 8 page
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