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Monte-Carlo simulation of the charged particle detector used in the NORDBALL gamma-ray spectrometer

The NORDBALL silicon detector array for detecting light charged particles emitted in fusion evaporation reactions was simulated with the Monte-Carlo method. The data from the reaction of 261 MeV Ni-58 ions with Cr-50 nuclei in a 4.8 mg/cm(2) thick target was used to adjust the simulation parameters. Relative population of residual nuclei in the reaction was determined, by comparing the intensities

CD40 expression in uterine tissues: A key regulator of cytokine expression by fibroblasts

CD40 is a cell surface receptor initially discovered on cells of the hemopoietic lineage. Its primary role on immune cells is to enhance their activation and hence their production of cytokines and immunomodulatory molecules. Recently, CD40 has also been detected on human fibroblasts. An emerging view of the fibroblast is that it is far more than a structural cell, being capable of intimate intera

Protein hydration dynamics in solution: a critical survey

The properties of water in biological systems have been studied for well over a century by a wide range of physical techniques, but progress has been slow and erratic. Protein hydration-the perturbation of water structure and dynamics by the protein surface-has been a particularly rich source of controversy and confusion. Our aim here is to critically examine central concepts in the description of

Real-time telediagnosis of radiological images through an asynchronous transfer mode network: the ARTeMeD project

The ARTeMeD project aims to solve problems of interactivity and real-time in teleradiology. It integrates personal multimedia facilities and patient data access in a common platform that allows radiologists to collaborate from remote sites through a suitable communication support. ARTeMeD is based on asynchronous transfer mode (ATM) network technology and an optimized manipulation of medical image

Automatic Reduction Procedures for Chemical Mechanisms in Reactive Systems

Popular Abstract in Swedish En av dagens största utmaningar är de stadigt ökande utsläppen av förorenande avgaser och drivhusgaser. Den största delen av dessa föroreningar kommer från förbränningsanläggningar och fordon. För att kunna minska utsläppen måste man förstå förbränningsprocesserna, och hur man kan kontrollera förbränningen. Utmaningen är att förbränningprocesser är mycket komplexa. Det To deal with complex physical and chemical processes in reactive systems, such as combustion processes, it is necessary to find methods that simplify modelling in such a way that it becomes both more comprehensible and practically useful. In the work reported here a method for automatically reducing chemical reaction mechanisms has been developed for use in computer simulations of various combusti

Relations between thyroid function, hepatic and lipoprotein lipase activities, and plasma lipoprotein concentrations

Lipoprotein concentrations and activities of lipoprotein lipase (LPL) and hepatic lipase (HL) were measured in 70 subjects with thyroid function ranging from overt hypothyroidism over subclinical hypothyroidism and euthyroidism to hyperthyroidism. In parallel with serum T3 (S-T3) concentrations increasing from low in hypothyroidism to high in hyperthyroidism there were gradually higher HL activiti

Comparison of vector finite-difference techniques for modal analysis

We compare a vector finite-difference method that correctly applies the boundary conditions at both horizontal and vertical dielectric interfaces (but not at corners or slanted interfaces) to algorithms that only approximately satisfy these boundary conditions. We find, rather unexpectedly, that for strongly guiding waveguides the boundary conditions imposed at the refractive- index discontinuitie

Methods for the determination in the nanomole range of lipids in liver fine-needle aspiration biopsies

Triglycerides and phospholipids 0.5-2mg (wet weight) of human liver material obtained by the fine-needle aspiration biopsy technique can be estimated after chloroform:methanol extraction by the determination of lipid phosphorus and glyceride glycerol. The methods are based on the colorimetric determination of inorganic phosphate after oxidation of the phospholipids and the enzymatic fluorometric d

Development of tolerance against toxic cyanobacteria in Daphnia

We tested whether previous exposure to a toxic strain of cyanobacteria (Microcystis) affects survival, growth, and reproduction of a common herbivore, Daphnia magna. Samples from three natural populations of D. magna were each divided into two parts; one part was fed a mixture of toxic Microcystis and the non-toxic green alga Scenedesmus whereas the other part was fed only Scenedesmus. After four

Physical activity, skeletal health and fractures in a long term perspective.

Exercise during adolescence, especially during the pre-pubertal years, builds a skeleton with a high bone mineral density (BMD) and possibly a larger skeleton with a different skeletal architecture. This would lead to a stronger skeleton more resistant to trauma. These changes could be of biological significance for fracture reduction, if they were maintained into old age where fragility fractures

Closed treatment of Jones fracture. Good results in 40 cases after 11-26 years

40 patients with transversal or short oblique fractures of the proximal shaft of the fifth metatarsal bone (Jones fracture) were treated with full weight bearing with or without elastic bandage in 39 cases and plaster cast immobilization in one. 24 cases were acute traumatic fractures, 14 stress fractures and 2 refractures. After 17 (11-26) years, 33 of the fractures had healed primarily, evidence

A 100MHz CMOS wideband IF amplifier

When the data rates of communication systems increase, wideband IF amplifiers are needed. It is also possible to use a single wideband intermediate frequency (IF) amplifier for a radio band with several narrow-band channels of varying strengths. The linearity is then critical, if intermodulation products are not to disturb weak channels. We try to find a topology for this new amplifier application

Det moderna åldrandet : Pensionärsorganisationernas bilder av åldrandet 1941-1995

Popular Abstract in Swedish Populärvetenskaplig sammanfattning Vilka är egentligen ”de äldre”? Vad innebär det att vara pensionär? Hur ska man åldras på rätt sätt? Frågor som dessa har under det nyss avslutade århundradet ställts och besvarats på många oliks sätt, beroende av sammanhang och tidsperiod. I vissa situationer har de äldres olikhet lyfts fram, i andra deras likhet. Ibland har åldrandetThe aim of the dissertation is to describe images of old age in the magazines of Sweden’s two largest pensioner organizations, and explain the character of those images in relation to the temporal contexts of the organizations and their aim to act as the representatives of pensioners. The study is based on the 329 and 330 magazines (1941–1995) that the organizations have submitted to attract membe

Kinematics of the distal tibiofibular syndesmosis - Radiostereometry in 11 normal ankles

In 11 healthy volunteers, the normal kinematics of the tibiofibular syndesmosis of the ankle during weight bearing and external rotation stress were compared to a nonweight-bearing neutral position by radiostereometry. We found very small rotations and displacements in this "normal" group, which indicated that the fibula is closely attached to the tibia, thereby preventing larger movements at the

Different islet protein expression profiles during spontaneous diabetes development vs. allograft rejection in BB-DP rats

Type 1 diabetes (T1D) is characterized by selective autoimmune destruction of the insulin producing beta-cells in the islets of Langerhans. When the beta-cells are destroyed exogenous administration of insulin is necessary for maintenance of glucose homeostasis. Allogeneic islet transplantation has been used as a means to circumvent the need for insulin administration and has in some cases been ab