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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

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

Parathyroid gland volume increases with postmaturational aging in the rat

To examine the pathophysiology of the age-related rise in the plasma concentration of parathyroid hormone (PTH), we studied the relationships among plasma immunoreactive PTH (iPTH), parathyroid gland volume, parathyroid cell proliferation rate, renal function, and blood Ca2+ in male Fischer 344 rats aged 6-28 mo. Plasma iPTH increased 2.5-fold between 6 and 28 mo and correlated with parathyroid gl

The HEATOX project

HEATOX is the acronym for a European Union-funded project entitled Heat-Generated Food Toxicants: Identification, Characterization, and Risk Minimization. Acrylamide will be the main experimental focus, but identification of unknown toxicants in heated carbohydrate-rich foods will also be attempted. The project includes research on formation chemistry, food technology, analytical methods, hazard c

Partitioning of nitrate uptake between trees and understory in oak forests

The nitrate reductase activity (NRA) was measured during spring, early summer and late summer in three deciduous forests, where the tree layer was dominated by oak. The nitrate assimilation capacities of the compartments of the above-ground and below-ground biomass of the understory and of the leaves and roots of the tree layer were calculated as NRA per unit biomass and NRA per unit area. The NRA

Cost-effectiveness of raloxifene in the UK: an economic evaluation based on the MORE study

Raloxifene treatment has been shown to reduce the risk of vertebral fractures and breast cancer in postmenopausal women. The long-term economic implications of treatment with raloxifene have not yet been investigated. The aim of this study was to assess the cost-effectiveness of treating postmenopausal women in the UK with raloxifene. A previously developed computer simulation model was used to es

Body memories and doing gender: Remembering the past and interpreting the present in order to change the future

Narrative is one method of tapping individual and collective memory where human experience is organized into temporally meaningful episodes and where a "point" is often made. In research projects that I have carried out about working life, "body stories" are often spontaneously related in making a "point." These stories exemplify "doing gender"-that is how gendered relations (that revolve around e

Prediction model for the impact sound level of lightweight floors

Lightweight floors are often troubled by poor impact-sound insulation. In order to develop and explain structures with acceptable insulation, a deterministic prediction model was developed. The paper considers transmission through the system and the response of the model. Excitation (as caused by the ISO-tapping machine) is considered in a separate paper [1]. The system description employs a spati

Detrusor contraction - Focus on muscarinic receptors

Stimulation of muscarinic receptors is a main mechanism for contractile activation of the detrusor from both animals and humans. Muscarinic receptors are coupled to G-proteins, but the signal transduction systems may vary. In general, M-1 , M-3 and M-5 receptors are considered to couple preferentially to G(q/11) , activating phosphoinositide hydrolysis, in turn leading to mobilization of intracell

Lipid-soluble smoke particles damage endothelial cells and reduce endothelium-dependent dilatation in rat and man

Background: Cigarette smoking is a strong risk factor for vascular disease and known to cause dysfunction of the endothelium. However, the molecular mechanisms involved are still not fully understood. Methods: In order to reveal the direct effects of lipid-soluble smoke particles on the endothelium, ring segments isolated from rat mesenteric arteries and human middle cerebral arteries (MCA) obtain