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A method to determine dynamic loads on spur gear teeth and on bearings

A method is described which can be used to calculate dynamic gear tooth force and bearing forces. The model includes elastic bearings. The gear mesh stiffness and the path of contact are determined using the deformations of the gears and the bearings. This gives contact outside the plane-of-action and a time-varying working pressure angle. In a numerical example it is found that the only important

Cellular function in multicellular system for hormone-secretion: electrophysiological aspect of studies on alpha-, beta- and delta-cells of the pancreatic islet

We review a neck method to explore the cellular functions in multicellular system by application of the perforated patch-clamp technique to intact pancreatic islet of Langerhans. Using this approach, the integrity of the islet is preserved and intercellular communication via gap junctions and paracrine processes are maintained. 13 using low-resistance patch electrodes, rapid current responses can

Incorporating nutrient content elasticity in the MAKEDEP model

The MAKEDEP model is designed to produce the time series of atmospheric deposition and nutrient uptake and cycling needed by dynamic soil chemistry models such as SAFE. A range of new features were implemented in the MAKEDEP model including separate treatment of several tree compartments (e.g. root, stem, bark, branch, canopy) and variable nutrient content in the different compartments. The mo

Effects of bioturbation on recruitment of algal cells from the "seed bank" of lake sediments

Effects of different bioturbators on recruitment of several nuisance algae, Anaboena spp. (Cyanophyta), Microcystis spp. (Cyanophyta), and Gonvostomum semen (Raphidophyta), from sediment to water were studied in a long-term laboratory experiment. Natural sediment, where macrofauna larger than 1 mm had been removed, was added to 18 aquaria. To each of six aquaria, individuals of Asellus aquaticus (

Age dependence of renal function: clearance of iohexol and p-amino hippurate in healthy males

Iohexol, a newly developed non-ionic contrast agent, has been recently documented as a reliable glomerular filtration marker. This study describes the age dependence of the single injection clearance of iohexol in a sample of healthy male volunteers ranging from 21 to 77 years of age. In parallel, renal plasma flow was studied by measuring the total clearance of p-amino hippuric acid administered

Improved selectivity of microbial biosensor using membrane coating. Application to the analysis of ethanol during fermentation

A ferricyanide mediated microbial biosensor for ethanol detection was prepared by surface modification of a glassy carbon electrode. The selectivity of the whole Gluconobacter oxydans cell biosensor for ethanol determination was greatly enhanced by the size exclusion effect of a cellulose acetate (CA) membrane. The use of a CA membrane increased the ethanol to glucose sensitivity ratio by a factor

Development of supersensitivity to methacholine in the rat detrusor following either parasympathetic denervation or decentralization

The male rat urinary bladder belongs to those few structures where both the post- and preganglionic parasympathetic nerves are accessible for severance. In the present study the sensitivity to the parasympathomimetic drug methacholine of muscle strips of either denervated or decentralized bladders was examined in vitro. One week postoperatively denervated and decentralized bladders were sensitized

Scaling and Mapping Regional Calculations of Soil Chemical Weathering Rates in Sweden

Weathering rates of base cations are crucial in critical load calculations and assessments of sustainable forestry. The weathering rate on a single site with detailed geological data can be modelled using the PROFILE model. For environmental assessments on a regional scale, the weathering rates for sites are scaled into regional maps. The step from sites to regional level requires focus on the spa

Low state complexity block codes via convolutional codes

A new class of block codes with low state complexity of their conventional trellis representations called double zero-tail terminated convolutional codes (DZT codes) is introduced. It is shown that there exist DZT-codes meeting the Varshamov-Gilbert bound on the minimum distance and having asymptotically optimal state complexity. Two ways of constructing DZT-codes are considered. Examples of DZT-c

Putative risk factors associated with retinopathy in patients with diabetes diagnosed at or after 30 years of age

In a cross-sectional study of diabetic patients diagnosed at or after 30 years, and with different stages of retinopathy, factors such as duration of diabetes, treatment mode, metabolic control, blood pressure, and clinical signs of nephropathy were examined. The different stages of retinopathy used were absence of retinopathy, simplex, and severe retinopathy. Patients with simplex and severe reti

Erythema Migrans in Primary Health Care

Lyme borreliosis (LB) is the most common vector-borne disease in the northern hemisphere, and southern Sweden is a highly endemic area. In over 70% of the cases, LB is represented by the non-disseminated cutaneous form erythema migrans (EM). This thesis has its focus on EM from a primary health care perspective in southern Sweden, including aspects on epidemiology, the clinical picture, gender dif

Synthesis of poly(styrene-graft-ethylene oxide) by ethoxylation of amide group containing styrene copolymers

Graft copolymers containing poly(ethylene oxide) side chains on a polystyrene backbone have been synthesized. Styrene copolymers synthesized by free radical mechanism and containing between 5 and 15 mol % acrylamide or methacrylamide were used as backbones. The amide groups in the copolymers were ionized by using potassium tert-butoxide or potassium naphthalene, and grafting was achieved by utiliz

Acoustic analysis of Chinese fricatives and affricates

A method of analyzing & describing the acoustic properties of fricatives is developed & applied to the fricatives & to the fricative components of the affricates of Standard Chinese. The method consists of making f spectra using the Fast Fourier Transform & analyzing the spectra in terms of critical bands. Three measures are proposed for characterizing the fricative spectra: the ce

Mapping of myeloperoxidase epitopes recognized by MPO-ANCA using human-mouse MPO chimers

Myeloperoxidase ( MPO) is one of the major target antigens of antineutrophil cytoplasmic autoantibodies ( ANCA) found in patients with small-vessel vasculitis and pauci-immune necrotizing glomerulonephritis. To date, the target epitopes of MPO-ANCA remain poorly defined. Human MPO-ANCA do not typically bind mouse MPO. We utilized the differences between human and mouse MPO to identify the target r

Turbulence characteristics and dispersion in a forest - tests of Thomson's random-flight model

A dispersion experiment, where the tracer SF6 Was released from line sources, was carried out within a young pine forest. Line sources made of silicone tubes were installed at different heights and distances from a tower. Vertical concentration profiles were measured on the tower and the samples were analysed with a gas chromatograph. The measured concentration profiles were compared to those calc