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The Lanthanide Elements in Stellar and Laboratory Spectra

The lanthanide elements (Z=57?71) are characterized by the filling of the 4f electronic subshell, which lies close in energy to the 5d and 6s subshells. As a result, the lanthanide spectra can be quite complicated in terms of the number of optical spectral lines, and in some cases their hyperfine structure and isotopic shifts are extremely large. These characteristics have great implications for a

Voluntary wheel running modulates glutamate receptor subunit gene expression and stress hormone release in Lewis rats

Lewis rats that are known to be addiction-prone, develop compulsive running if they have access to running wheels. The present experiments were aimed 1) to evaluate the activation of stress systems following chronic and acute voluntary wheel running in Lewis rats by measurement of hormone release and gene expression of neuropeptides related to hypothalamic-pituitary-adrenocortical (HPA) axis activ

A heterologous reductase affects the redox balance of recombinant Saccharomyces cerevisiae

Recombinant Saccharomyces cerevisiae harbouring the xylose reductase (XR) gene XYL1 from Pichia stipitis was grown in anoxic chemostat culture at two different dilution rates. At each dilution rate a transient experiment, encompassing a shift in the sugar content of the medium from glucose to glucose plus xylose was performed. The steady states at the beginning and the end of the transients were c

Analysis Of Heat Transfer And Transport Processes In Sofcs Involving Internal Reforming Reactions

The heat transfer rates in solid oxide fuel cells (SOFCs) are controlled by various operating and design parameters and have significant effects on chemical reactions and coupled transport processes. In this article, the considered composite duct consists of a porous anode layer for the internal reforming reactions of methane, the fuel gas flow duct, and the solid plate. A fully three-dimensional

Hypoglycaemia leads to an increased QT interval in normal men

Hypoglycaemia is presumed to be the cause of death in about 3% of insulin-treated diabetic patients. Some of these patients suffer from hypoglycaemic brain damage, but the majority have no evident brain damage and are supposed to have died from other causes such as a cardiac arrhythmia. The putative mechanism is a hypoglycaemia-induced prolongation of the QT interval which increases the risk of ma

BCG vaccination scar associated with better childhood survival in Guinea-Bissau

BACKGROUND: Recent studies have suggested that Bacille Calmette-Guerin (BCG) vaccination may have a non-specific beneficial effect on infant survival and that a BCG scar may be associated with lower child mortality. No study has previously examined the influence of BCG vaccination on cause of death. METHODS: Two cohorts (A and B) were used to describe the mortality pattern for children with and wi

Visual adaptations in the night-active Wasp Apoica pallens

The apposition compound eye of the nocturnal polistine wasp Apoica pallens shows, in comparison to the closely related diurnal wasp Polistes occidentalis, specific adaptations to vision at low light intensities. When considering recent work on nocturnal and diurnal bees, general principles for dim-light vision in hymenopterans become evident: The rhabdom diameters in nocturnal bees and wasps are 4

Bridging the gaps: stakeholder-based strategies for risk reduction and financing for the urban poor

This paper explores the options that can be used by aid organizations working in human settlement development to more effectively address disaster risk management. Qualitative research was carried out in El Salvador at both the household and institutional levels - to analyze the needs, capacities and perspectives of slum dwellers and aid organizations. A clearer understanding of the gaps between w

Continuous exposure to glial cell line-derived neurotrophic factor to mature dopaminergic transplants impairs the graft's ability to improve spontaneous motor behavior in parkinsonian rats.

Functional recovery following intrastriatal transplantation of fetal dopaminergic neurons in animal models of Parkinson's disease is, at least in part, dependent on the number of surviving dopaminergic neurons and the degree of graft-derived dopaminergic reinnervation of the host striatum. In the present study, we analyzed whether continuous exposure of glial cell line-derived neurotrophic factor

Quasi-bom-Lie algebras, central extensions and 2-cocycle-like identities

This paper introduces the notion of a quasi-hom-Lie algebra, or simply, a qhl-algebra, which is a natural generalization of hom-Lie algebras introduced in a previous paper [J.T. Hartwig, D. Larsson, S.D. Silvestrov, Deformations of Lie algebras using sigma-derivations, math. QA/0408064]. Quasi-hom-Lie algebras include also as special cases (color) Lie algebras and superalgebras, and can be seen as

Nondigestible carbohydrates in the diets of infants and young children: A commentary by the ESPGHAN Committee on Nutrition

The consumption of nondigestible carbohydrates is perceived as beneficial by health professionals and the general public, but the translation of this information into dietary practice, public health recommendations, and regulatory policy has proved difficult. Nondiaestible carbohydrates are a heterogeneous entity, and their definition is problematic. Without a means to characterize the dietary com

Structure and transport properties of a charged spherical microemulsion system

Structure and transport properties of an oil-in-water microemulsion of weakly charged spherical micelles were studied experimentally using viscosity, NMR self-diffusion, and static and dynamic light scattering as well as theoretically by Brownian dynamics and Monte Carlo simulations and the Poisson-Boltzmann equation. The micelles contain decane covered by the nonionic surfactant pentaethylene gly

Inner-shell 2p photoionization and Auger decay of atomic silicon

A detailed experiment on 2p photoionization and subsequent Auger decay of atomic silicon is presented. Fine-structure-resolved photoelectron and Auger electron spectra are interpreted with the aid of large-scale multiconfiguration calculations. Energy separation and the relative cross sections of the 2p ionized fine-structure states of Si+ are given. The complete 2p Auger electron spectrum of Si i

Control-theoretic Analysis of Admission Control Mechanisms for Web Server Systems

Web sites are exposed to high rates of incoming requests. The servers may become overloaded during temporary traffic peaks when more requests arrive than the server is designed for. An admission control mechanism rejects some requests whenever the arriving traffic is too high and thereby maintains an acceptable load in the system. This paper presents how admission control mechanisms can be designe

Studies of host-graft interactions in vitro.

Progenitor and stem cell transplantation represent therapeutic strategies for retinal disorders that are accompanied by photoreceptor degeneration. The transplanted cells may either replace degenerating photoreceptors or secrete beneficial factors that halt the processes of photoreceptor degeneration. The present study analyzes whether rat retinal progenitor cells differentiated into photoreceptor

Double helicity asymmetry in inclusive midrapidity pi(0) production for polarized p+p collisions at root s=200 GeV

We present a measurement of the double longitudinal spin asymmetry in inclusive pi(0) production in polarized proton-proton collisions at roots=200 GeV. The data were taken at the Relativistic Heavy Ion Collider with average beam polarizations of 0.27. The measurements are the first in a program to study the longitudinal spin structure of the proton, using strongly interacting probes, at collider

Investigating time-of-flight spin-echo modulation for small-angle neutron scattering through experiments and simulation

A spin-echo-modulated small-angle neutron scattering (SEMSANS) instrument in a time-of-flight (TOF) mode will be able to excel at pulsed neutron sources such as the European Spallation Source (ESS), currently under construction. This work compares experimental data from a TOF SEMSANS setup, where a spatial beam modulation of a white beam is obtained using triangular field coils, with Monte Carlo r