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Effects of intracellular acidification and varied temperature on force, stiffness and speed of shortening in frog muscle fibres.

This study aimed to establish whether the temperature-dependent effect of acidification on maximum force observed in mammalian muscles also applies to frog muscle. Measurements of force, stiffness, and unloaded velocity of shortening in intact single muscle fibers from the anterior tibialis muscle of Rana temporaria were performed between 0 and 22degreesC during fused tetani in H2CO3CO2-buffered R

The n ->pi* electronic transition in microsolvated formaldehyde. A coupled cluster and combined coupled cluster/molecular mechanics study

In this article, we study the n - pi* electronic transition in aqueous microsolvated formaldehyde using the coupled cluster (CC) and coupled cluster/molecular mechanics (CC/MM) methods. The CC models used are the coupled cluster singles and doubles (CCSD) and the coupled cluster second-order approximate singles and doubles (CC2) methods. The CC/MM model includes electrostatic and mutual polarizati

Development of a tRNA-Synthetase Microarray for Protein Analysis

Proteins are composed of 20 different amino acids. In the translation process, each of these 20 amino acids is specifically recognized by their cognate aminoacyl-tRNA synthetase. The fidelity of this recognition system is essential if translation is to function properly. The development of an in vitro system based on this recognition scheme would make a powerful analytical tool with which to analy

On the Efficient Implementation and Time-Updating of the Linearly Constrained Minimum Variance Beamformer

The linearly constrained minimum variance (LCMV) method is an extension of the classical minimum variance distortionless response (MVDR) filter, allowing for multiple linear constraints. Depending on the spatial filter length and the desired frequency grid, a direct computation of the resulting spatial beampattern may be prohibitive. In this paper, we exploit the rich structure of the LCMV express

Magnetic order in semiconducting, ferromagnetic Ga1-xMnxAs

Magnetic resonance studies allow us to distinguish paramagnetic, ferromagnetic and ferrimagnetic phases in Ga1-xMnxAs. The transition from ferromagnet to ferrimagnet is correlated with a metal to insulator transition. The analysis of spin wave resonance spectra, which occur in the ferrimagnetic phase, allows us to estimate the magnitude and the distance dependence of exchange coupling. The experim

A randomized, double-blind, dose-comparison study of weekly interferon beta-1a in relapsing MS

Background: Interferon beta-1a (IFNbeta-1a; Avonex) is effective for the treatment of relapsing MS; however, the optimal dose of IFNbeta-1a is not known. Objective: To determine whether IFNbeta-1a 60 mug IM once weekly is more effective than IFNbeta-1a 30 mug IM once weekly in reducing disability progression in relapsing MS. Methods: In a double-blind, parallel-group, dose-comparison study, 802 pa

Traffic Safety Dimensions and the Power Model to Describe the Effect of Speed on Safety

Traffic safety work needs different methods and tools in order to choose and evsaluate traffic safety measures. The thesis contributes to this problem by presenting and visualizing a method which describes the traffic safety situation in several dimensions. The method used to describe the traffic safety problem shows the potential of a simultanous presentation and evaluation of these dimensions an

Near-threshold measurement of the He-4(gamma,n) reaction

A near-threshold He-4(gamma, n) cross-section measurement has been performed at MAX-lab. Tagged photons from 23 < Ey < 42 MeV were directed toward a liquid He-4 target, and neutrons were detected by time-of-flight in two liquid-scintillator arrays. Seven-point angular distributions were measured for eight photon energies. The results are compared to experimental data measured at comparable energie

Dosimetric response to gamma rays and neutrons of a tissue-equivalent microstrip gas counter

In recent years a new generation of tracking particle detectors has been developed for particle physics experiments. One such detector, the microstrip gas counter (MSGC) is similar to the multiwire proportional chamber but consists of fine strips of metal on a substrate rather than suspended wires. The main feature of this device is the sub-millimetre readout spacing. When filled with tissue-equiv

Nanomagnetic and Micromagnetic Properties of Rocks Minerals and Sulphide Oxidation Products

Magnetic and related properties of rocks and products from oxidation of sulphide minerals have been investigated with magnetisation measurements (rocks and oxidation products), magnetic force microscopy (rocks), scanning electron microscopy (rocks and oxidation products), transmission electron microscopy (oxidation products), Mössbauer spectroscopy (oxidation products) and powder X-ray diffraction

Relation between Vascular Risk Factors and Carotid Plaque Cell Composition and Viability in Elderly Patients

Objectives: Carotid stenosis is a crucial cause of ischemic stroke. Recent studies suggest that one of the most important effects of lipid-lowering statins is to stabilize vulnerable plaques. However, it remains to be determined if this effect is secondary to the lowering of plasma cholesterol levels or due to a direct effect of statins on plaques stability. Design and main outcome measures: In th

Cytogenetic abnormalities in a hemangiopericytoma of the spleen.

To date, only 16 cytogenetically abnormal hemangiopericytomas (HP) have been reported. Despite this low number, some characteristic karyotypic features have already emerged: most HP are near-diploid and breakpoints in 12q13, 12q24, and 19q13 seem to be common, with t(12;19)(q13;q13) being a recurrent translocation. Here, we report the first case of a probably benign splenic HP with chromosomal abn

Empirical Sudies in Trade, Growth and Integration

The present study is composed of a series of six independent yet related articles treating various aspects of international trade and economic growth. In Chapter two the effects of European Integration (EI) on long-run economic growth is studied. Contrary to earlier empirical results long-run effects of EI are identified. As a development Chapter three examines two potential channels linking EI to

New structure information on Mg-30, Mg-31 and Mg-32

The fast timing beta gamma gamma(t) method was applied to investigate the level lifetimes in Mg-30,Mg-31,Mg-32. Levels in Mg have been populated in beta and beta-delayed neutron emission of Na, at the ISOLDE facility. From the gamma gamma coincidences a number of new states have been identified and new level schemes were constructed for 30 31,32 Mg. The following preliminary half lives have been d