476 research outputs found
Holography, Gauge-Gravity Connection and Black Hole Entropy
The issues of holography and possible links with gauge theories in spacetime
physics is discussed, in an approach quite distinct from the more restricted
AdS-CFT correspondence. A particular notion of holography in the context of
black hole thermodynamics is derived (rather than conjectured) from rather
elementary considerations, which also leads to a criterion of thermal stability
of radiant black holes, without resorting to specific classical metrics. For
black holes that obey this criterion, the canonical entropy is expressed in
terms of the microcanonical entropy of an Isolated Horizon which is essentially
a local generalization of the very global event horizon and is a null inner
boundary of spacetime, with marginal outer trapping. It is argued why degrees
of freedom on this horizon must be described by a topological gauge theory.
Quantizing this boundary theory leads to the microcanonical entropy of the
horizon expressed in terms of an infinite series asymptotic in the
cross-sectional area, with the leading `area-law' term followed by finite,
unambiguously calculable corrections arising from quantum spacetime
fluctuations.Comment: 12 Pages Latex, 5 eps figures, based on invited talk given at the
PAQFT08 Conference held at Nanyang University, Singapore in November 200
Current-driven orbital order-disorder transition in LaMnO3
We report significant influence of electric current on the orbital
order-disorder transition in LaMnO3. The transition temperature T_OO, thermal
hysteresis in the resistivity (rho) versus temperature (T) plot around T_OO,
and latent heat L associated with the transition decrease with the increase in
current density. Eventually, at a critical current density, L reaches zero. The
transition zone, on the other hand, broadens with the increase in current
density. The states at ordered, disordered, and transition zone are all found
to be stable within the time window from ~10^-3 to ~10^4 seconds.Comment: 7 pages including 5 figures; resolution of Fig.1 is better here than
the published versio
Neuroimaging in paediatric patients with developmental delay
Background: Aim and objectives of the study were to radiologically evaluate paediatric patients with developmental delay (DD), assess the relative prevalence of abnormal brain MRI, further categorize them based on the abnormal imaging findings and structures affected. The purpose of this study is to diagnose the underlying etiology that helps in early treatment and amelioration of the condition, parental counselling regarding the outcome of the child, providing an estimate of child’s developmental potential and the recurrence risk in siblings.Methods: 135 paediatric patients of the age 3 months to 15 years with DD referred to department of radiology were investigated with MRI scans of the brain via 1.5T Siemens scanner after making the child sleep or sedated. The sequences used were: axial T1, axial T2, axial FLAIR, axial DWI, axial ADC, axial SWI, axial PHASE, sagittal T1 and coronal FLAIR. CT scan of the brain was done only when indicated on 128 slice Siemens Somatom perspective scanner. Informed consent shall be taken from patient’s parents. Clinical and demographic details of the enrolled patients were noted in the Performa. Data collected was analysed using descriptive and inferential statistics.Results: Out of 135 children with DD, 69.1% (n=92) were male and 31.9% (n=43) were female. Majority of these children belonged to 3 months to 1 year and 2 to 5 years of age group. About 81.4% (n=110) of children with DD had abnormal findings in MRI. Among children with abnormal MRI findings, 42.9% had hypoxic ischemic changes, 6.6% had congenital malformations and non-specific causes, respectively 4.4% had neurodegenerative and occlusive neurovascular conditions, respectively 3.7% had CSF disorders and neoplasms, respectively 2.9% had infection associated changes and non-traumatic intracranial bleed, respectively 2.2% had metabolic disorders and 0.7% had demyelination. Majority of cases had ventricular abnormality, followed by the corpus callosum.Conclusions: DD presents with a wide spectrum of etiologies, clinical findings and MRI features ranging from completely normal to abnormal. The present study could establish the various morphological appearances of DD on MRI and further categorize them into various subgroups be effective in diagnosis, management and prognosis determination processes
Generalized Hawking-Page Phase Transition
The issue of radiant spherical black holes being in stable thermal
equilibrium with their radiation bath is reconsidered. Using a simple
equilibrium statistical mechanical analysis incorporating Gaussian thermal
fluctuations in a canonical ensemble of isolated horizons, the heat capacity is
shown to diverge at a critical value of the classical mass of the isolated
horizon, given (in Planckian units) by the {\it microcanonical} entropy
calculated using Loop Quantum Gravity. The analysis reproduces the Hawking-Page
phase transition discerned for anti-de Sitter black holes and generalizes it in
the sense that nowhere is any classical metric made use of.Comment: 9 Pages, Latex with 2 eps figure
INTERNATIONAL JOURNAL OF PHARMACY & LIFE SCIENCES A breakthrough in health care textiles -antiviral surgical gown
Abstract The surgical gowns were originally used to protect patients from post-surgery infection caused by contaminants in the environment. In the recent health care scenario, the function of surgical gowns has become bidirectional. They serve to minimize the cross-infection between patients and health care workers. The health care workers are mainly being exposed to various blood borne pathogens when performing surgeries or post surgeries. The surgical gowns are specifically used to protect the health care workers from being exposed to infectious agent's particularly bloodborne pathogens such as human immunodeficiency virus (HIV), hepatitis B and C virus, which could be acquired by contact between the contaminated body fluids and non-intact skin or mucous membranes. Health care workers in operating rooms, isolation areas, emergency rooms and intensive care units are in absolute and essential necessity of Protective clothing. As a part of personal protection, surgical gowns are used as protective equipment, widely in healthcare facilities. Surgical gowns can be constructed by either single-use materials or reusable materials. Each of these has their own advantages and disadvantages. Woven reusable surgical gowns can be made of tightly woven all-cotton muslin, blended sheeting, polyester sheeting and composite materials
Charge-monopole versus Gravitational Scattering at Planckian Energies
The amplitude for the scattering of a point magnetic monopole and a point
charge, at centre-of-mass energies much larger than the masses of the
particles, and in the limit of low momentum transfer, is shown to be
proportional to the (integer-valued) monopole strength, assuming the Dirac
quantization condition for the monopole-charge system. It is demonstrated that,
for small momentum transfer, charge-monopole electromagnetic effects remain
comparable to those due to the gravitational interaction between the particles
even at Planckian centre-of-mass energies.Comment: 9 pages, revtex, IMSc/93-4
Impact of soil moisture and plant population on yield components and yield of maize (Zea mays)
Experiment was conducted with three water levels such as 100, 75 and 50 % with three spacing, viz. normal, narrow and reduced narrow spacing of maize. Reducing the plant spacing, enhanced the plant population per unit area which increases maize yield even under reduced soil moisture level. Individual treatments of normal irrigation practice, narrow plant spacing and its interaction registered better performance of kernel, stover yield and yield attributes
CLINICAL OUTCOMES OF USE OF HYDROXYCHLOROQUINE IN PARADOXICAL TUBERCULOSIS-IMMUNE RECONSTITUTION INFLAMMATORY SYNDROME IN HIV-INFECTED PATIENTS.
 Objective: Immune reconstitution inflammatory syndrome (IRIS) is an inflammatory reaction in HIV-infected patients after initiation of antiretroviral therapy (ART) resulting from restored immunity to specific infectious or non-infectious antigens. The most common condition where IRIS has been reported is tuberculosis (TB). Various mechanisms have been proposed and studied to account for the immune regulatory role of hydroxychloroquine (HCQ). This study is done to identify clinical outcome in HIV-TB patients with IRIS after given with HCQ.Methods: An uncontrolled longitudinal study was conducted among HIV-infected patients with TB initiated on ART and developed IRIS between July 2013 and June 2015 in a South Indian HIV care hospital.Results: A total of 40 patients have developed IRIS with mean age of 35.87 years and 77.5 % of them were males. At the time of IRIS occurrence, the mean body mass index was found to be 19.17 kg/m2 and CD4 count was 200 cells/mm3. The time duration took to get improvement in majority of the patients was 4–12 weeks.Conclusion: There was definite improvement seen in patients who received HCQ in TB-IRIS condition
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