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Optimized Gaussian basis sets for Goedecker-Teter-Hutter pseudopotentials

We have optimized the exponents of Gaussian s and p basis functions for the elements H, B-F and Al-Cl using the pseudopotentials of (Goedecker, Teter and Hutter 1996 Phys. Rev. B 54 1703) by minimizing the total energy of dimers. We found that this procedure causes the Gaussians to be somewhat more localized than the usual procedure, where the exponents are optimized for atoms. We further found th

EGF infusion stimulates the proliferation and migration of embryonic progenitor cells transplanted in the adult rat striatum

Immature progenitor cells (generated by in vitro propagation) may provide a useful alternative to primary cells (from dissected embryonic tissue) for transplantation if their migratory and proliferative and differentiation properties can be controlled and directed in vivo. In this study E15 murine EGF-responsive progenitor cells were transplanted to the striatum of adult rats. Simultaneously, thes

Linking resource matching and dispersal

We study theoretically the effect of inter-habitat migration on the distribution of population sizes between two habitats, and compare this distribution with the expected ideal free distribution (IFD). Whenever emigration from the two habitats is asymmetric, or when there is a survival cost during migration, the resulting equilibrium distribution of population sizes deviates from the IFD. This res

Stratospheric ozone depletion: High arctic tundra plant growth on Svalbard is not affected by enhanced UV-B after 7 years of UV-B supplementation in the field

The response of tundra plants to enhanced UV-B radiation simulating 15 and 30% ozone depletion was studied at two high arctic sites (Isdammen and Adventdalen, 78 degrees N, Svalbard).The set-up of the UV-B supplementation systems is described, consisting of large and small UV lamp arrays, installed in 1996 and 2002. After 7 years of exposure to enhanced UV-B radiation, plant cover, density, morpho

Solid-state characteristics and redispersible properties of powders formed by spray-drying and freeze-drying cereal dispersions of varying (1→3,1→4)--glucan content

Cereal powders containing 33, 18 and 4% (w/w) (1→3,1→4)--glucan, prepared from cereal suspensions, had distinct differences in surface morphology as observed by scanning electron microscopy, depending both on the drying process (spray- or freeze-drying) and the dietary fibre level. Freeze-drying produced powders with a ‘flake-like’ matrix, without particle formation and similar matrix morphology i

Agricultural performance on marginal land in Eastern Inner Mongolia, China -- Development in the pre- and post-1978 reform periods

Rapid economic development in the aftermath of the Chinese post-1978 reforms has resulted in a shrinking of grain grown area in the southern and eastern regions of the country which in turn is believed to have put the marginal northern regions under increased pressure. This paper examines key indicators of agricultural performance as well as cultivated land area development of the pre- and post-19

Fiscal policy in Sweden: effects of EMU criteria convergence

This paper investigates the sustainability of Swedish fiscal policy performed during the period 1963-2000. The main emphasis is on assessing the effects of changes in fiscal policy, such as changes in taxes or public spending. On the basis of Johansen's VAR and the augmented Granger causality tests, the results show that taxes and spending are causally related in the long-run and the homogeneity c

One in 10 ovarian cancer patients carry germ line BRCA1 or BRCA2 mutations : results of a prospective study in Southern Sweden

At least 10% of all ovarian cancers are estimated to have a hereditary background. Hereditary breast-ovarian cancer (HBOC) due to mutations in the BRCA genes is a major cause of hereditary ovarian cancer, although its frequency and relationship to age and family history in unselected series of ovarian cancers is not completely known. We report here the results of a full mutational screening analys

Geographic patterns of genetic differentiation and plumage colour variation are different in the pied flycatcher (Ficedula hypoleuca)

The pied flycatcher is one of the most phenotypically variable bird species in Europe. The geographic variation in phenotypes has often been attributed to spatial variation in selection regimes that is associated with the presence or absence of the congeneric collared flycatcher. Spatial variation in phenotypes could however also be generated by spatially restricted gene flow and genetic drift. We

Temperature dependence of the gain profile for THz quantum cascade lasers

We study the rapid decrease of peak gain in resonant-phonon THz Quantum Cascade Lasers with increasing temperature. The effect of various microscopic scattering processes on the gain profile as a function of temperature is discussed. We argue that increased broadening, prim arily due to increased impurity scattering, and not diminishing population inversion, is the main reason for the reduction of

Adolescent occasional smokers, a target group for smoking cessation? The Nord-Trondelag Health Study, Norway, 1995-1997

BACKGROUND: Adolescent smokers are often unsuccessful in quitting and difficult to retain in cessation programs. In health promotion, focusing on the right target groups is essential. Aim. The aim was to examine if adolescent occasional smokers differ from daily smokers, and if possible differences could be useful for targeted smoking cessation programs. METHODS: Ninety-one percent of all teenager

On the dosimetric behaviour of photon dose calculation algorithms in the presence of simple geometric heterogeneities: comparison with Monte Carlo calculations

A comparative study was performed to reveal differences and relative figures of merit of seven different calculation algorithms for photon beams when applied to inhomogeneous media. The following algorithms were investigated: Varian Eclipse: the anisotropic analytical algorithm, and the pencil beam with modified Batho correction; Nucletron Helax-TMS: the collapsed cone and the pencil beam with equ

Discounting and clinical decision making: physicians, patients, the general public, and the management of asymptomatic abdominal aortic aneurysms.

Clinical decisions often entail in intertemporal trade-off. Moreover, they often involve physicians of different specialities. In an experiment dealing with the management of small asymptomatic abdominal aortic aneurysms (a clinically relevant problem) we find that specialists in internal medicine exhibit higher implicit discount rates than vascular surgeons, general practitioners, and actual and

Phylogeny of cetrarioid lichens (Parmeliaceae) inferred from ITS and beta-tubulin sequences, morphology, anatomy and secondary chemistry.

Phylogenetic relationships within the family Parmeliaceae (lichenized ascomycetes) with emphasis on the heterogeneous group of cetrarioid lichens are reconstructed. The results are based on cladistic analyses of DNA-sequences, morphological and chemical data. Almost all currently recognized cetrarioid genera were included in the analyses together with parmelioid and alectorioid members of the pres

A comparative analysis of B cell-mediated myelin oligodendrocyte glycoprotein-experimental autoimmune encephalomyelitis pathogenesis in B cell-deficient mice reveals an effect on demyelination.

We have investigated the role of B cells in myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) using B cell-deficient mice muMT) and mice bearing the X-linked immunodeficiency (xid). The mice were immunized with MOG(1-125 )in complete Freund's adjuvant but without use of pertussis toxin. B cell-deficient muMT mice on different genetic backgrounds (C57

Family history of cancer as a risk factor for second malignancies after Hodgkin's lymphoma

This study estimated the risk of second primary malignancies after Hodgkin's lymphoma (HL) in relation to family history of cancer, age at diagnosis and latency, among 6946 patients treated for HL in Sweden in 1965-1995 identified through the Swedish Cancer Register (SCR). First-degree relatives (FDRs) to the HL patients and their malignancies were then ascertained together with their malignancies

Increased retinopathy occurrence in type 1 diabetes patients with increased serum levels of the advanced glycation endproduct hydroimidazolone

Purpose: We aimed to investigate associations between serum levels of the advanced glycation endproduct methylglyoxal-derived hydroimidazolone (MG-H1) and retinopathy in a sample of patients with type 1 diabetes. Methods: We conducted a cross-sectional study in a Scandinavian ophthalmology outpatient clinic on 61 randomly selected patients with type 1 diabetes. Blood samples and retinal photograph

A new specific chromosomal rearrangement, t(8;16) (p11;p13), in acute monocytic leukaemia

The translocation t(8;16) (p11;p13) was found as the sole deviation from the normal karyotype in three patients with acute monocytic leukaemia. The bone marrow morphology was strikingly similar in the two cases where smears were available for re-evaluation: the leukaemic cells showed signs of differentiation, and active erythrophagocytosis was a particularly conspicuous feature. We suggest that t(

Psychological test performance during experimental challenge to toluene and n-butyl acetate in cases of solvent-induced toxic encephalopathy

OBJECTIVES: This study determined whether performance in neurobehavioral tests deteriorates during subjectively annoying chemical challenge below known neurotoxic thresholds among persons with toxic encephalopathy with subjective hypersensitivity to chemicals. METHODS: Subjects with symptoms and previous neuropsychological test results compatible with toxic encephalopathy (TE) of either type 2A (

The determinables of explanatory mechanisms

Sometimes instances of perceived causation turn out to lack causal relata. The reasons may vary. Causation may display itself as prevention, or as omission, and in some cases causation occurs within such complex environments that few of the things we associate with causes and effects are true of them, etc. But even then, there may be causal explanations to be had. This suggests that the explanator