Emissivity measurements of reflective surfaces at near-millimeter wavelengths

We have developed an instrument for directly measuring the emissivity of reflective surfaces at near-millimeter wavelengths. The thermal emission of a test sample is compared with that of a reference surface, allowing the emissivity of the sample to be determined without heating. The emissivity of the reference surface is determined by one’s heating the reference surface and measuring the increase in emission. The instrument has an absolute accuracy of Δe = 5 x 10^-4 and can reproducibly measure a difference in emissivity as small as Δe = 10^-4 between flat reflective samples. We have used the instrument to measure the emissivity of metal films evaporated on glass and carbon fiber-reinforced plastic composite surfaces. We measure an emissivity of (2.15 ± 0.4) x 10^-3 for gold evaporated on glass and (2.65 ± 0.5) x 10^-3 for aluminum evaporated on carbon fiber-reinforced plastic composite

Influence of sodium pyruvate on Neurospora fructose diphosphatase

Influence of sodium pyruvate on fructose diphosphatas

Triple-horizon spherically symmetric spacetime and holographic principle

We present a family of spherically symmetric spacetimes, specified by the density profile of a vacuum dark energy, which have the same global structure as the de Sitter spacetime but the reduced symmetry which leads to a time-evolving and spatially inhomogeneous cosmological term. It connects smoothly two de Sitter vacua with different values of cosmological constant and corresponds to anisotropic vacuum dark fluid defined by symmetry of its stress-energy tensor which is invariant under the radial boosts. This family contains a special class distinguished by dynamics of evaporation of a cosmological horizon which evolves to the triple horizon with the finite entropy, zero temperature, zero curvature, infinite positive specific heat, and infinite scrambling time. Non-zero value of the cosmological constant in the triple-horizon spacetime is tightly fixed by quantum dynamics of evaporation of the cosmological horizon.Comment: Honorable Mentioned Essay - Gravity Research Foundation 2012; submitted to Int. J. Mod. Phys.

Evaluation of a rare case of orbital venous varix with multiple intracranial venous malformations using prone MRI technique

Orbit is a common site for vascular lesions in all age groups, with venous malformations being the most common type. Orbital varices are a rare subset of venous malformation which is a vascular hamartoma that communicate with normal orbital veins. The mainstay of diagnosis and differentiation from other vascular and neoplastic lesions of orbit is demonstration of change in size of lesion on dynamic maneuvers. In this article, we present a case of left orbital venous varix which showed enlargement on Valsalva maneuver. The patient was evaluated using prone MRI technique to demonstrate increase in the size of lesion. Multiple asymptomatic developmental venous anomalies were detected on brain screening, which is a known association

Generalised Separable Solution of Double Phase Flow through Homogeneous Porous Medium in Vertical Downward Direction Due to Difference in Viscosity

In this paper the instability (fingering) phenomenon in a double phase immiscible (oil and water) flow through the homogeneous porous medium with mean capillary pressure in the vertical downward direction is discussed. The mathematical formulation of this problem yields a nonlinear partial differential equation and the generalised separable solution is given in the exponential form. The numerical solution and graphical presentation is given using MAT LAB coding

Can Quantum de Sitter Space Have Finite Entropy?

If one tries to view de Sitter as a true (as opposed to a meta-stable) vacuum, there is a tension between the finiteness of its entropy and the infinite-dimensionality of its Hilbert space. We invetsigate the viability of one proposal to reconcile this tension using $q$-deformation. After defining a differential geometry on the quantum de Sitter space, we try to constrain the value of the deformation parameter by imposing the condition that in the undeformed limit, we want the real form of the (inherently complex) quantum group to reduce to the usual SO(4,1) of de Sitter. We find that this forces $q$ to be a real number. Since it is known that quantum groups have finite-dimensional representations only for $q=$ root of unity, this suggests that standard $q$-deformations cannot give rise to finite dimensional Hilbert spaces, ruling out finite entropy for q-deformed de Sitter.Comment: 10 pages, v2: references added, v3: minor corrections, abstract and title made more in-line with the result, v4: published versio

Psychosocial factors influencing acceptance of laparoscopic tubal ligation

Research Problem: What are the psychosocial factors influencing acceptance of laparoscopic tubal ligation? Objectives: To study psychosocial factors influencing acceptance of laparoscopic tubal ligation. Study Design: Hospital based study by questionnaire method. Setting: Postpartum unit of Irwin Group of Hospitals, M.P. Shah, MedicalCollege, Jamnagar, Gujarat. Participants: Acceptors of laparoscopic tubal ligation. Sample Size: 500 acceptors. Study Variables: Age of acceptor, family size, contra­ceptive use. Statistical Analysis: By proportions. Result: Out of 500 acceptors, 58% belonged to rural areas. Mean number of children per acceptor was 4.01 ± 1.8. Mean age of acceptor was 28.3±4.3years. 76.8% of the acceptors did not use any contraceptive prior to acceptance of laparoscopic tubal ligation. An important finding of the study was that monetary incentives had no role in acceptance of tubal ligation

Comparison of upper respiratory viral load distributions in asymptomatic and symptomatic children diagnosed with SARS-CoV-2 infection in pediatric hospital testing programs

The distribution of upper respiratory viral loads (VL) in asymptomatic children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unknown. We assessed PCR cycle threshold (Ct) values and estimated VL in infected asymptomatic children diagnosed in nine pediatric hospital testing programs. Records for asymptomatic and symptomatic patients with positive clinical SARS-CoV-2 tests were reviewed. Ct values were (i) adjusted by centering each value around the institutional median Ct value from symptomatic children tested with that assay and (ii) converted to estimated VL (numbers of copies per milliliter) using internal or manufacturer data. Adjusted Ct values and estimated VL for asymptomatic versus symptomatic children (118 asymptomatic versus 197 symptomatic children aged 0 to 4 years, 79 asymptomatic versus 97 symptomatic children aged 5 to 9 years, 69 asymptomatic versus 75 symptomatic children aged 10 to 13 years, 73 asymptomatic versus 109 symptomatic children aged 14 to 17 years) were compared. The median adjusted Ct value for asymptomatic children was 10.3 cycles higher than for symptomatic children