Theoretical search for Chevrel phase based thermoelectric materials

We investigate the thermoelectric properties of some semiconducting Chevrel phases. Band structure calculations are used to compute thermopowers and to estimate of the effects of alloying and disorder on carrier mobility. Alloying on the Mo site with transition metals like Re, Ru or Tc to reach a semiconducting composition causes large changes in the electronic structure at the Fermi level. Such alloys are expected to have low carrier mobilities. Filling with transition metals was also found to be incompatible with high thermoelectric performance based on the calculated electronic structures. Filling with Zn, Cu, and especially with Li was found to be favorable. The calculated electronic structures of these filled Chevrel phases are consistent with low scattering of carriers by defects associated with the filling. We expect good mobility and high thermopower in materials with the composition close to (Li,Cu)$_4$Mo$_6$Se$_8$, particularly when Li-rich, and recommend this system for experimental investigation.Comment: 4 two-column pages, 4 embedded ps figure

Effect of Lates calcarifer seed stocking on the survival and production of Indian major carps reared in a freshwater coastal pond in Konkan region

The experiment indicated feasibility of culturing Indian major carps seed with Lates calcarifer, if the size of Indian major carps is larger. In the present investigation the average growths of Catla catla, Labeo rohita and Cirrhinus mrigala are recorded as 1193, 1120 and 821 g, respectively, during the year 1997-98, 1998-99 and 1999-2000 in 7.5 months. Complete harvesting of L. calcarifer is essential before stocking of new seed. The average growth of L. calcarifer was recorded as about 670 g during the above period. About 5000 numbers of Indian major carps fry per hectare can be stocked under the present culture syste

An evaluation of the quality of discharge summaries from the general paediatric wards at Chris Hani Baragwanath Academic Hospital, Johannesburg, South Africa

Background. Hospital discharge summaries are deemed to be an essential part of the medical record in South Africa, but formal assessment of their quality is rarely undertaken. At Chris Hani Baragwanath Academic Hospital (CHBAH) in Johannesburg, medical admission notes (bedletters) are difficult to retrieve from the hospital archives and the discharge summary is often the only readily available medical record that documents details of the hospital admission.Objectives. To determine the proportion of discharge summaries that were appropriately completed for children admitted to the general paediatric wards at CHBAH.Methods. A retrospective review of discharge summaries completed for children admitted from 1 May to 31 July 2016 was undertaken. The completeness of the following demographic and clinical variables was assessed: patient identifiers, hospital outcome, HIV infection status and anthropometric status. The documentation of correct International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10) codes was assessed in children diagnosed with any form of lower respiratory tract infection (LRTI), which is the commonest diagnosis recorded in hospitalised children at CHBAH.Results. Discharge summaries were available for 1 148 (78.3%) of 1 466 children admitted during the study period. For completed discharge summaries, 80.1 - 93.3% of patient identifiers and 91.4% of patient outcomes were appropriately completed. HIV exposure was documented in 84.7% of summaries. Anthropometric parameters, including weight and length/height at admission and discharge weight, were appropriately completed in 91.4%, 70.9% and 50.0% of summaries, respectively. The ICD-10 code for children with LRTI was appropriately recorded by medical staff in 338 (67.2%) of 503 cases. ICD‑10 codes and anthropometric parameters, which are important clinical parameters in the paediatric follow-up consultation, were both correctly recorded for only 21.6% of children who required follow-up clinical consultations at CHBAH.Conclusions. Compared with similar studies, both the rate of completion and the quality of completed discharge summaries were modest in this tertiary academic teaching hospital. As discharge summaries are crucial medical documents, interventions to improve their completeness rate and quality need to be developed

Gravitational collapse of null fluid on the brane

We first obtain the analogue of Vaidya's solution on the brane for studying the collapse of null fluid onto a flat Minkowski cavity on the brane. Since the back-reaction of the bulk onto the brane is supposed to strengthen gravity on the brane, it would favour formation of black hole as against naked singularity. That is the parameter window in the initial data set giving rise to naked singularity in the 4D Vaidya case would now get partially covered.Comment: 12 pages, latex, 3 figures, submitted to Phys.Lett.

Entanglement perturbation theory for the quantum ground states in two dimensions

A simple, general and practically exact method, Entanglement Perturbation Theory (EPT), is formulated to calculate the ground states of 2D macroscopic quantum systems with translational symmetry. An emphasis will be placed on the applicability of EPT to fermions. We will discuss some preliminary evidences which indicate a potential of EPT

Soil and land resource evaluation for rural agricultural land use planning – A case study from hot semiarid ecosystem of Western India

The farmers of today are expected to maintain rural agricultural landscapes with production mandates that restrict their mandate to integrate conservation plans with landscape management. In this context, an effort was made to evaluate the degree of land use, management and conservation practices adopted in Lagadwal village of Dhule district through detailed soil survey and photopedological interview walks and discussions with farmers. The landscape photographs were thematically arranged and analyzed to construct and narrate theories of land care by local farmers on erosive high hills covering thirty per cent of area (>620m elevation) and supporting extremely shallow Budkhed and Lagadwal series in southern part of the village. The photo views of erosive mid hill landscapes with gullies and landslip areas (40% of area, 600 to 620m) have soil association of moderately shallow Lagadwal thana series on crests / side slopes to very deep Brahmasila and Gaikot series in lower slopes whereas low hills (35% of area, 580 to 600m) with ridge lines and drainage depressions have moderately deep Lagadwal tola series. The farmer’s did not perceive the long term landscape changes occurred due to partially effective conservation plans and pressing financial issues. The photographs revealed the unclear realties of harvesting farm produce on these steeply sloping erosive landscapes emphasizing more on explicit policy toward land management practices and offers opportunity to the farmer’s to change their farm production management activities. The photographs were not intended to evaluate land care per se but offers an insight to the farmers how they look of the land at landscape level

Projected SO(5) Hamiltonian for Cuprates and Its Applications

The projected SO(5) (pSO(5)) Hamiltonian incorporates the quantum spin and superconducting fluctuations of underdoped cuprates in terms of four bosons moving on a coarse grained lattice. A simple mean field approximation can explain some key feautures of the experimental phase diagram: (i) The Mott transition between antiferromagnet and superconductor, (ii) The increase of T_c and superfluid stiffness with hole concentration x and (iii) The increase of antiferromagnetic resonance energy as sqrt{x-x_c} in the superconducting phase. We apply this theory to explain the ``two gaps'' problem found in underdoped cuprate Superconductor-Normal- Superconductor junctions. In particular we explain the sharp subgap Andreev peaks of the differential resistance, as signatures of the antiferromagnetic resonance (the magnon mass gap). A critical test of this theory is proposed. The tunneling charge, as measured by shot noise, should change by increments of Delta Q= 2e at the Andreev peaks, rather than by Delta Q=e as in conventional superconductors.Comment: 3 EPS figure

Higher dimensional dust collapse with a cosmological constant

The general solution of the Einstein equation for higher dimensional (HD) spherically symmetric collapse of inhomogeneous dust in presence of a cosmological term, i.e., exact interior solutions of the Einstein field equations is presented for the HD Tolman-Bondi metrics imbedded in a de Sitter background. The solution is then matched to exterior HD Scwarschild-de Sitter. A brief discussion on the causal structure singularities and horizons is provided. It turns out that the collapse proceed in the same way as in the Minkowski background, i.e., the strong curvature naked singularities form and that the higher dimensions seem to favor black holes rather than naked singularities.Comment: 7 Pages, no figure