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It is proved that existence of a density function is both necessary and sufficient for almost global stability in a nonlinear system.

Very heavy elements (Pt, Au, Hg, Tl, and Bi) are found to be enhanced inthe atmospheres of the chemically peculiar stars of the upper mainsequence by up to a million times the solar system levels. Suchenhancements are believed to result from atmospheric dynamics (i.e.,diffusion) rather than scenarios that dredge up nuclear-processedmaterial to the surface or transfer processed material between bin

A 2-month psychological questionnaire concerning pregnancy was answered by 20,920 nondiabetic mothers of singletons. Retrospective analysis showed increased levels of islet autoantibodies (1A) in 290 (1.4%) newborns. High IA levels in the child's cord blood correlated strongly with IA levels in the mother (GADA r = 0.91, P < 0.0001; IA-2A r = 0.75, P = 0.0001). High IA levels were found in newborn

New basis sets of the atomic natural orbital (ANO) type have been developed for the first, second, and third row transition metal atoms. The ANOs have been obtained from the average density matrix of the ground and lowest excited states of the atom, the positive and negative ions, and the atom in an electric field. Scalar relativistic effects are included through the use of a Douglas-Kroll-Hess Ha

The identification of genes underlying quantitative-trait loci (QTL) for complex diseases, such as rheumatoid arthritis, is a challenging and difficult task for the human genome project. Through positional cloning of the Pia4 QTL in rats, we found that a naturally occurring polymorphism of Ncf1 (encoding neutrophil cytosolic factor 1, a component of the NADPH oxidase complex) regulates arthritis s

Proton acceleration from the interaction of ultra-short laser pulses with thin foil targets at intensities greater than 10(18) W cm(-2) is discussed. An overview of the physical processes giving rise to the generation of protons with multi-MeV energies, in well defined beams with excellent spatial quality, is presented. Specifically, the discussion centres on the influence of laser pulse contrast

Long term follow up of 16 homosexual men and 78 intravenous drug abusers who were chronic carriers of hepatitis B surface antigen (HBsAg) showed fundamental differences between the two groups. Viral replication, expressed by the presence of hepatitis B e antigen, lasted for four years or more in 10 out of 14 (71%) of the homosexual men whereas it was not present in 43 out of 73 (59%) of the drug a

The critical effect of load representation in voltage stability studies is discussed in this paper. Under the same conditions in the system, the load representation will affect the location of the operating point in a P-V curve representation, leading the system closer to or further from the collapse point. The use of dynamic load models in voltage stability studies is motivated, especially in tho

In this article I examine whether an influential theory of mechanisms proposed by Peter Machamer, Lindley Darden and Carl Craver can accommodate polygenic effects. This theory is both interesting and problematic, I will argue, because it ascribes a central role to activities. In it, activities are needed not only to constitute mechanisms but also to perform their causal role. These putative functi

The immune system is an important part of the physiology of higher organisms. In the immune system antibodies play a key role in neutralizing and clearing potentially lethal threats from the environment. The importance of antibodies in the immune system has made them come to the attention as a tool in chemistry and medicine. This thesis, which is based on four original papers, deal with antibody d

We present the results of realistic N-body modelling of massive star clusters in the Magellanic Clouds, aimed at investigating a dynamical origin for the radius-age trend observed in these systems. We find that stellar-mass black holes, formed in the supernova explosions of the most massive cluster stars, can constitute a dynamically important population. If a significant ensemble is retained (her

Although it is generally anticipated that innovation as such leads to regional prosperity (Asheim et al. 2011) there is lack of empirical evidence that confirms the direct linkage between the innovation capabilities of regions and welfare increase. It is suggested that entrepreneurship can be seen as a missing link that helps to transfer innovations into business outcomes (Braun et al. 2012). The

The paper presents the emerging field of integrated control and CPU-time scheduling, where more general scheduling models and methods that better suit the needs of control systems are developed. This creates possibilities for dynamic and flexible integrated control and scheduling frameworks, where the control design methodology takes the availability of computing resources into account during desi

Biological invasions offer fertile grounds for studying evolutionary ecology because species’ contact histories are uncharacteristically well-defined. As a result, invasions can be used to gain glimpses of the earliest micro-evolutionary responses of natural populations to new species’ interactions by studying changes in behaviour, physiology or morphology in space and time. Here, the known histor

ABSTRACT: BACKGROUND: In Guinea-Bissau HIV-1, HIV-2, and HTLV-I are prevalent in the general population. The natural history of HIV/HTLV-I single and dual infections has not been fully elucidated in this population. Previous studies have shown that combinations of these infections are more common in older women than in men. The present study compares mortality associated with HIV-1, HIV-2, and HTL

The results of a theoretical study of the ground state, 1(1)A(g), and of the lowest B-1(u) states of trans-stilbene are presented. The vertical and adiabatic excitation energies of the lowest B-1(u) states have been computed using multiconfigurational SCF theory, followed by second-order perturbation. theory. It is shown that the two lowest excited states are separated by a small energy gap in the