52,449 research outputs found
Effectiveness of One-dimensional gas models for black holes
A one-dimensional gas model has been constructed and shown to provide correct
expressions for entropies for extremal and near-extremal BTZ black holes.
Recently suggested boosting of black strings is used to compute the entropy for
the Schwarzschild black hole also from this gas model.Comment: 14 pages, Latex, misprints corrected, reference added and minor
changes mad
Three Dimensional Gauge Theory with Topological and Non-topological Mass: Hamiltonian and Lagrangian Analysis
Three dimensional (abelian) gauged massive Thirring model is bosonized in the
large fermion mass limit. A further integration of the gauge field results in a
non-local theory. A truncated version of that is the Maxwell Chern Simons (MCS)
theory with a conventional mass term or MCS Proca theory. This gauge invariant
theory is completely solved in the Hamiltonian and Lagrangian formalism, with
the spectra of the modes determined. Since the vector field constituting the
model is identified (via bosonization) to the fermion current, the charge
current algebra, including the Schwinger term is also computed in the MCS Proca
model.Comment: Eight pages, Latex, No figures
Black hole state counting in loop quantum gravity
The two ways of counting microscopic states of black holes in the U(1)
formulation of loop quantum gravity, one counting all allowed spin network
labels j,m and the other only m labels, are discussed in some detail. The
constraints on m are clarified and the map between the flux quantum numbers and
m discussed. Configurations with |m|=j, which are sometimes sought after, are
shown to be important only when large areas are involved. The discussion is
extended to the SU(2) formulation.Comment: 5 page
Reply to comment by Zaslavskii on extremal black hole action
It is shown that Zaslavskii's misunderstanding of our published proof of the
irrelevance of all extremal black hole configurations (whether with equal
charge and mass or not) rests on his refusal to see the essential difference
between the correct inequality governing extremal and non-extremal actions and
his incorrect version.Comment: 1 page, REVTeX, adapted from reply in PRL 80, 3413 (1998
Anemia in Antiretroviral Naïve HIV/AIDS Patients: A Study from Eastern India
Background: Hematological manifestations are common throughout the course of HIV infection. Impact of anemia is the most significant among them. The present study was undertaken to evaluate the etiologies underlying anemia in HIV/AIDS. Methods This was a non randomized cross sectional observational study conducted in a tertiary care hospital of India over a period of 2 years. One hundred and fifty HIV patients were screened. Thorough clinical and laboratory evaluation was done in 50 randomly selected anemic cases. Results: Proper etiological diagnosis could be reached in 46 patients. Among them correlation between Hb% and CD4 count was statistically insignificant (p = 0.074, r = 0.47) whereas it was significant with absolute lymphocyte and CD4 count (p = 0.006, r = 0.41). There was better correlation of bone marrow iron status with percent saturation of transferrin (p = 0.003, r = 0.54) than with serum ferritin (p = 0.055, r = 0.09). Bone marrow iron status did not have any relationship with CD4 count. Anemia of chronic disease was the commonest etiology (37%) followed by HIV related myelodysplastic syndrome (31%), iron deficiency anemia (13%), bone marrow suppression due to direct involvement by some infective process (7%). Aplastic anemia, multiple myeloma, Hodgkin’s disease, pure red cell aplasia, hemophagocytic lymphohistiocytosis and vitamin B12 deficiency were detected in one case (2%) each. Conclusions: Etiologies of anemia in HIV/AIDS are multifactorial with anemia of chronic disease being the commonest. For screening of iron deficiency in this group, percent saturation is a better tool than serum ferritin. Absolute lymphocyte count can sometimes be used as a surrogate marker of immunological status in antiretroviral naïve HIV patients, particularly in resource poor areas
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