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Modeling CNS neurodegeneration by overexpression of disease-causing proteins using viral vectors.

Defective handling of proteins is a central feature of major neurodegenerative diseases. The discovery that neuronal dysfunction or degeneration can be caused by mutations in single cellular proteins has given new opportunities to model the underlying disease processes by genetic modification of cells in vitro or by generation of transgenic animals carrying the disease-causing gene. Recent develop

Evolutionsgrader hos Teloschistacéerna - en långsam process.

The evolutionary process and its impact on speciation and emergence of genera is discussed briefly for the Teloschistaceae. Many facts which have been recognized mainly from studies of morphological variation within populations in addition to analyses of structural variation from herbarium material speak for a conceivable slow evolutionary process represented in this family. Some examples are disc

Regional Nutrient Budgets in Forest Soils in a Policy Perspective

Popular Abstract in Swedish Skogen är en av Sveriges mest betydelsefulla naturresurser. Utöver det ekonomiska värdet är skogen även viktig ur ett ekologiskt, socialt och kulturellt perspektiv. För att uppnå ett långsiktigt uthålligt skogsbruk måste alla dessa aspekter beaktas. Uthålliga näringsbalanser i den brukade skogsmarken är nödvändiga för att bevara produktionsförmågan samt minska risken föSweden's forests are one of its most important natural resources, as well as being important from ecological and social perspectives. Nutrient sustainability is essential to maintain the production capacity and reduce the effects of acidification and eutrophication. Nutrient sustainability is strongly affected by anthropogenic influences such as air pollution and forestry practices. Regional asses

Measurement of diffusion coefficients in gel beads: Random and systematic errors

The method of calculating diffusion coefficients in gel beads based on transient experiments of solute uptake from a finite volume has been studied theoretically. Monte Carlo simulation was used to investigate the effect of random errors in the concentration measurements. The influence of sampling frequency and diffusion direction was investigated. Systematic errors derived from an assumption of c

Quality of life in old people with and without cancer.

The aim was to investigate the influence of age and gender on quality of life (QoL), complaints, and the presence and nature of self-reported diseases in persons aged 75 and older with cancer (n = 150), compared to a matched group without cancer (n = 138). A second aim was to investigate factors associated with poor QoL in people aged 75 and older. QoL was measured with Short Form (SF-12) and Euro

Expression of nitric oxide synthase in bladder smooth muscle cells: Regulation by cytokines and L-arginine

Purpose: The expression and regulation of the different isoforms of nitric oxide synthase (NOS) in bladder smooth muscle cells are controversial and to our knowledge have not yet been studied systematically. Therefore, the expression and regulation of NOS were studied in rat bladder smooth muscle cells after stimulation with cytokines, lipopolysaccharide and L-arginine. Materials and Methods: Prim

Limitations of the pulse-shape technique for particle discrimination in planar Si detectors

Limitations of the pulse-shape discrimination (PSD) technique - a promising method to identify the charged particles stopped in planar Si-detectors - have been investigated. The particle resolution turned out to be basically determined by resistivity fluctuations in the bulk silicon which cause the charge-collection time to depend on the point of impact. Detector maps showing these fluctuations ha

Synthesis and characterization of cobalt silicide films on silicon

Cobalt silicide has emerged as a leading contact material in silicon technology due to its low resistivity, high stability and small lattice mismatch. In this study, 0.2-0.4 mu m thick Co films were deposited on Si(100) wafers by RF magnetron sputtering at room temperature, and annealed at temperatures from 600 to 900 degrees C in vacuum. As-deposited and annealed samples were characterized by Rut

Why don't chimps talk and humans sing like canaries?

We focus on two problems with the evolutionary scenario proposed: (1) It bypasses the question of the origins of the communicative and semiotic features that make language distinct from, say, pleasant but meaningless sounds. (2) It does little to explain the absence of language in, for example, chimpanzees: Most of the selection pressures invoked apply just as strongly to chimps. We suggest how th

The COST 259 directional channel model - Part I: Overview and methodology

This paper describes a model for mobile radio channels that includes consideration of directions of arrival and is thus suitable for simulations of the performance of wireless systems that use smart antennas. The model is specified for 13 different types of environments, covering macro- micro- and picocells. In this paper, a hierarchy of modeling concepts is described, as well as implementation as

Fano effect in a quantum-ring-quantum-dot system with tunable coupling

Transport measurements are presented on a quantum ring that is tunnel-coupled to a quantum dot. When the dot is in the Coulomb blockade regime, but strongly coupled to the open ring, Fano line shapes are observed in the current through the ring, when the electron number in the dot changes by 1. The symmetry of the Fano resonances is found to depend on the magnetic flux penetrating the area of the

Elementary excitations of ferromagnetic metal nanoparticles

We present a theory of the elementary spin excitations in transition-metal ferromagnet nanoparticles which achieves a unified and consistent quantum description of both collective and quasiparticle physics. The theory starts by recognizing the essential role played by spin-orbit interactions in determining the energies of ferromagnetic resonances in the collective excitation spectrum and the stren

Tests of association between the humoral immune response of red-winged blackbirds (Agelaius phoeniceus) and male plumage, testosterone, or reproductive success

We explored the potential relationships between male traits, reproductive success, testosterone levels in the breeding season, and Immoral immunocompetence in male red-winged blackbirds (Agelaius phoeniceus). Males responded to a single injection of diphtheriatetanus vaccine by producing antibodies to both antigens. The primary responses to each antigen were positively correlated with each other,

Antihyperglycaemic treatment of type 2 diabetes: results from a national diabetes register

Aim. - To describe clinical characteristics and antihyperglycaemic treatment patterns in patients with varying duration of diabetes. Methods. - We performed a cross-sectional survey of 61 890 type 2 diabetic (DM2) patients from the Swedish National Diabetes Register (NDR) in 2004. We also analysed the effect of types of treatment and risk factors on glycaemic control in a longitudinal cohort study

A case of dermatofibrosarcoma protuberans with a ring chromosome 5 and a rearranged chromosome 22 containing amplified COL1A1 and PDGFB sequences

Dermatofibrosarcoma protuberans (DFSP) is a cutaneous tumour of borderline malignancy, the cytogenetic features of which include the translocation t(17;22)(q22;q13) or, more commonly, supernumerary ring chromosomes containing material from 17q22 and 22q13. These rearrangements result in the COL1A1/PDGFB fusion gene. Here, we describe a case of DFSP displaying a ring chromosome 5 together with a la

Serum 25-hydroxyvitamin D in a West African population of tuberculosis patients and unmatched healthy controls

Background: Little is known regarding vitamin D deficiency (VDD) in African populations and in tuberculosis (TB) patients. VDD has been shown to be associated with TB. Objective: We aimed to compare the degree of vitamin D insufficiency (VDI) and VDD in TB patients and healthy adult controls in a West African population. Design: An unmatched case-control study was performed at a Demographic Survei