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Influence of the characteristic curve on the clinical image quality of lumbar spine and chest radiographs.

The "European Guidelines on Quality Criteria for Diagnostic Radiographic Images" do not address the choice of the film characteristic (H&D) curve, which is an important parameter for the description of a radiographic screen–film system. The image contrast of clinical lumbar spine and chest radiographs was altered by digital image processing techniques, simulating images with different H&D

Titration of fatty acids solubilized in catonic, nonionic and anionic micelles: Theory and experiment.

The titration properties of a fatty acid solubilized in different types of micelles, cationic, anionic and nonionic, have been investigated experimentally and theoretically. The solution containing micelles, counterions, and added salt was treated as a dielectric continuum in the Monte Carlo simulations. The dielectric permittivity of the interior of the micelle can have a profound effect on the c

Surveillance of influenza A virus in migratory waterfowl in northern Europe

We conducted large-scale, systematic sampling of influenza type A virus in migratory waterfowl (mostly mallards [Anas platyrhynchos]) at Ottenby Bird Observatory, southeast Sweden. As with previous studies, we found a higher prevalence in fall than spring, and among juveniles compared with adults. However, in contrast to other studies, we found that prevalence in spring was sometimes high (mean 4.

Approximating a sum of random variables with a lognormal

A simple, novel, and general method is presented in this paper for approximating the sum of independent or arbitrarily correlated lognormal random variables (RV) by a single lognormal RV. The method is also shown to be applicable for approximating the sum of lognormal-Rice and Suzuki RVs by a single lognormal RV. A sum consisting of a mixture of the above distributions can also be easily handled.

Application Oriented Programming and Control of Industrial Robots

Efficient use of industrial robots requires a strong interplay between user level commands, the motion control system, and external equipment. It should also be possible for an experienced application engineer to tailor the motion control to a specific application in a convenient way, instead of deficient utilization of the device or tricky user programming which is often the case today. A layered

Effects of increased solar ultraviolet radiation on terrestrial ecosystems

Elevated solar UV-B radiation associated with stratospheric ozone reduction may exert effects on terrestrial ecosystems through actions on plants, microbes, and perhaps on some animals. At the ecosystem level, the effects are less well understood than at the molecular and organismal levels. Many of the most important, yet less predictable, consequences will be indirect effects of elevated UV-B act

Modeling of finger-joint failure in glued-laminated timber beams

This paper presents a novel approach to the modeling of failure of finger-joints in glued-laminated beams. A nonlinear strain-softening model with stochastic material parameters was used to characterize the failure zone of the finger-joint. Monte Carlo simulations of the behavior of finger-joint laminations and of laminated beams were performed using the finite-element method. Various lamination t

Characterization of a new large area HPGe X-ray detector for low beam current application

In the new sub-micron beamline at the Lund Nuclear Microprobe facility a special large area HPGe X-ray detector has been installed. It consists of eight 100-mm(2)-size detector elements arranged in an annular formation around the beam entrance hole. Different parameters like FWHM, FWTM, peak-to-background ratio and peak-to-valley ratio for each individual detector element as well as their sum spec

Hepatitis C genotypes in Finland determined by RFLP

Genotyping of hepatitis C virus (HCV) is important because of its clinical and epidemiological implications. We report here the distribution of HCV genotypes in various patient groups in Finland using a rapid and reliable HCV typing method based on restriction fragment length polymorphism (RFLP) of the amplified DNA from the 5' non-coding region of the genome. The reaction product from the primary

Oxidative stress decreases extracellular homocysteine concentration in human hepatoma (HepG2) cell cultures

Background: Mild hyperhomocysteinemia is associated with premature vascular disease. The mechanism behind the vascular injuries is, however, still unknown. Homocysteine may be catabolized in the trans sulfuration pathway to cysteine. Cystathionine beta-synthase, which catalyses the first step in the transsulfuration pathway is redox-sensitive. We have therefore investigated total extracellular hom

Trait anxiety and modeled exposure as determinants of Self-Reported Annoyance to Sound, Air Pollution and Other Environmental Factors in the home

Objectives We examined to what degree annoyance ratings to noise, air pollution and other common environmental factors in the home environment could be considered to mirror personality disposition in terms of habitual anxiety level and, when appropriate, objectively modeled noise and nitrogen emission (NOx). Methods A trait anxiety scale was introduced in a cross-sectional public health survey wit

Novel glycolipid variations revealed by monoclonal antibody immunochemical analysis of weak ABO subgroups of A

Background and Objectives The chemical basis of the subgroups of A is largely unknown. We used thin-layer chromatography immunochemical staining techniques together with a range of characterized monoclonal reagents to analyse glycolipids isolated from a variety of weak subgroups. Materials and Methods Glycolipids isolated from red cells collected from nine genetically defined individuals of the ra

A field test of the relationship between habitat area and population size for five perennial plant species.

The population sizes of five perennial vascular plant species confined to old unimproved dry grasslands were assessed, viz. Anthericum ramosum, Filipendula vulgaris, Silene nutans, Thymus pulegioides, and Thymus serpyllum. All populations within the region were included. Only for Filipendula vulgaris and Thymus serpyllum, significant relationships between habitat area and population size were foun

Effects of heat on meat proteins - Implications on structure and quality of meat products

Globular and fibrous proteins are compared with regard to structural behaviour on heating, where the former expands and the latter contracts. The meat protein composition and structure is briefly described. The behaviour of the different meat proteins on heating is discussed. Most of the sarcoplasmic proteins aggregate between 40 and 60 ° C, but for some of them the coagulation can extend