Poverty in Metropolitan Areas of the U.S.: Causes and Consequences

This paper re-examines the determinants of poverty using a pooled data set of 331 U.S. Metropolitan Statistical Areas (MSAs) measured over four decennial censuses from 1970 to 2000. Our principal conclusions are that the determinants of poverty that we have identified are relatively stable predictors of poverty levels, but that results for first differences are sensitive to the time period of estimation. We also examine whether poverty as an initial condition has an effect on future growth in incomes and/or employment, and our tentative conclusion is that a higher level of existing poverty is indeed a detriment to future growth.

Charmonium excited state spectrum in lattice QCD

Working with a large basis of covariant derivative-based meson interpolating fields we demonstrate the feasibility of reliably extracting multiple excited states using a variational method. The study is performed on quenched anisotropic lattices with clover quarks at the charm mass. We demonstrate how a knowledge of the continuum limit of a lattice interpolating field can give additional spin-assignment information, even at a single lattice spacing, via the overlap factors of interpolating field and state. Excited state masses are systematically high with respect to quark potential model predictions and, where they exist, experimental states. We conclude that this is most likely a result of the quenched approximation.Comment: Fixed typos: normalisation of chi-squared, some operator projections in appendix, missing lattice irrep tabl

Active heat exchange system development for latent heat thermal energy storage

Active heat exchange concepts for use with thermal energy storage systems in the temperature range of 250 C to 350 C, using the heat of fusion of molten salts for storing thermal energy are described. Salt mixtures that freeze and melt in appropriate ranges are identified and are evaluated for physico-chemical, economic, corrosive and safety characteristics. Eight active heat exchange concepts for heat transfer during solidification are conceived and conceptually designed for use with selected storage media. The concepts are analyzed for their scalability, maintenance, safety, technological development and costs. A model for estimating and scaling storage system costs is developed and is used for economic evaluation of salt mixtures and heat exchange concepts for a large scale application. The importance of comparing salts and heat exchange concepts on a total system cost basis, rather than the component cost basis alone, is pointed out. The heat exchange concepts were sized and compared for 6.5 MPa/281 C steam conditions and a 1000 MW(t) heat rate for six hours. A cost sensitivity analysis for other design conditions is also carried out

Kinetics of mobilization of neutrophils and their marrow pool in protein-calorie deficiency

Migration of marrow neutrophils under basal conditions and their mobilization, following subcutaneous implantation of cover slips, were investigated in groups of protein-deficient rats, using 3HTdR with sequential autoradiography of the peripheral blood smears. Animals fed a protein-rich diet served as controls. The pattern of appearance of labeled neutrophils in the blood was identical in the two groups under basal conditions. However, a higher percentag of labeled neutrophils appeared earlier in the blood following cover slip implantation in the deficient rats as compared to controls. The inflammatory exudate on the cover slips was low throughout the period of observation in deficient animals, with a delay in the appearance of monocytes. A pool of mature neutrophils resides in the bone marrow. It is proposed that in PCM there is atrophy of all neutrophil compartments, including that of the marrow pool, associated with a proportionate reduction in the efflux of cells from one compartment to another. This proportionate reduction in efflux would explain the normal kinetics of migration of neutrophils under basal conditions in the deficient rats in spite of a reduction in the marrow pool. On the other hand, in cover slip-implanted deficient rats, appearance of larger numbers of labeled neutrophils in the blood is attributed to a reduction in size of the marrow pool. This hypothesis is substantiated by the experiments in protein-deficient monkeys in which estimation of the marrow pool of neutrophils revealed a marked reduction in the deficient animals. It is further proposed that a diminuation of the marrow pool of neutrophils and retarded mobilization of cells at the site of inflammation are important mechanism responsible for the increased susceptibility of the malnourished host to infections

Economic Liberalization - A Stumbling Block in the Commercialization of Indigenous Calcium Silicide Technology

Indian ferro alloy industry is passing through one of its worst periods by the process of economic liberalization. Its production in our country is coming down mainly due to inadequate indigenous demand, non-availability of exports and high power cost as compared to other competing countries. The indigenous calcium silicide technology developed at National Metallurgical Laboratory; Jamshedpur could not be commercialized on account of thenew economic liberalization policy of Government of India

Butyl Rubber-Nylon Composites with Improved Flame Retardancy & Gas Impermeability

Butyl rubber, because of its high packing density and chemical structure is inherently impermeable to air and gases. However, the elastomer is highly flammable owing to its neat carbon-hydrogen backbone structure. The particular rubber is extensively being used as coating materials for nylon, cotton, polyester etc., for development of clothing outfits for service personnel working in hazardous chemical environments . It is, therefore , essential to evolve flame retardant butyl rubber compositions which could make such clothings impermeable to chemical agents having adequate flame retardancy.The present paper describes an attempt towards using various chemical additives viz. brominated phenyl ethers, chlorinated paraffin, various inorganic oxides and halogenated elastomer, either singly or in combinations as potential flame retardants in bromo-butyl rubber compositions. The cements were then prepared by adding toluene to these compositions (20 to 30% solid content). The homogenised cements were then applied on both sides of nylon fabric with varying add -on concentrations in a laboratory coating machine with doctors blade specially designed for this purpose. The coated fabrics were cured at different temperatures in step curing between 70-150°C, tested for impermeability against hazardous warfare agents and found to offer enhanced protection against these chemicals . Standard test methods e.g. (a) exposure of the fabric to direct flame as per BS method 3119 (b) limited oxygen index as per ASTM specification D-2663 were followed in the evaluation of flame retardancy. The fabrics showed no after glow- low after flame (2.5 sec. against 6 sec. specified)and 7.2 cm char length against 12 cm max. permissible value. The hysicomechanical' properties e.g., breaking and tensile strengths were determined . Morphology and rubber fabric adhesion were studied using Scanning Electron Microscopy

Effect of Fe substitution on the magnetic, transport, thermal and magnetocaloric properties in Ni50Mn38-xFexSb12 Heusler alloys

The structural, magnetic, transport, thermal and magnetothermal properties of quaternary Heusler alloys Ni50Mn38-xFexSb12 have been studied. Powder x-ray diffraction and temperature dependence of magnetization studies reveal that with addition of Fe in Mn site, the martensitic transition shifts to lower temperatures. It is also found that the martensitic transition becomes broader for the higher Fe concentrations. The metamagnetic transition in M(H) isotherms becomes very prominent in x=2 and vanishes for x=3 and 4. A maximum positive magnetic entropy change of 14.2 J/kg K is observed for x=2 at 288 K for 50 kOe. Resistivity shows an abrupt decrease across the martensitic transition in all the alloys, except x=6, which does not have the martensitic transition. Maximum negative magnetoresistance of 21% has been obtained for x=2 at 50 kOe. The same alloy also shows an exchange bias field of 288 Oe.Comment: 28 pages, 10 figures, This paper is accepted to be published in Journal of Applied Physic