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Stress hormone dynamics: an adaptation to migration?

The hormone corticosterone (CORT) is an important component of a bird's response to environmental stress, but it can also have negative effects. Therefore, birds on migration are hypothesized to have repressed stress responses (migration-modulation hypothesis). In contrast to earlier studies on long-distance migrants, we evaluate this hypothesis in a population containing both migratory and reside

AC Conductance of DNA molecule at low temperature

Using nonequilibrium Green's function technique, we have investigated the ac conductance of poly(C)-poly(G) DNA molecule at low temperature. Our results indicate that thermal fluctuations of DNA hopping energy will play a profound role for the ac conductance. It smoothes out the conductance curves at high ac signal frequency while does not suppress it substantially. The dependences of the ac condu

Mutations in the thiol-disulfide oxidoreductases BdbC and BdbD can suppress cytochrome c deficiency of CcdA-defective Bacillus subtilis cells

Cytochromes of the c type in the gram-positive bacterium Bacillus subtilis are all membrane anchored, with their heme domains exposed on the outer side of the cytoplasmic membrane. They are distinguished from other cytochromes by having heme covalently attached by two thioether bonds. The cysteinyls in the heme-binding site (CXXCH) in apocytochrome c must be reduced in order for the covalent attac

Yeast genome sequencing: the power of comparative genomics

For decades, unicellular yeasts have been general models to help understand the eukaryotic cell and also our own biology. Recently, over a dozen yeast genomes have been sequenced, providing the basis to resolve several complex biological questions. Analysis of the novel sequence data has shown that the minimum number of genes from each species that need to be compared to produce a reliable phyloge

Two BRCA1-positive epithelial ovarian tumors with metastases to the central nervous system: a case report

BACKGROUND: Cerebral metastasis secondary to ovarian cancer is a rare phenomenon. While no clear relationship to known prognostic factors is found, others suggest this as a biologically diverse behavior of ovarian cancer. CASES: In a pilot study, 37 invasive epithelial ovarian cancer samples were analyzed to detect the frequency of BRCA1/BRCA2 mutations in the south of Sweden (results published).

Pancreatitis-associated pulmonary injury - effects of Lexipafant, a PAF-antagonist

Objective. Pulmonary injury is an important determinant of outcome in severe acute pancreatitis. The aim of this experimental study was to investigate the potential effect of lexipafant, a platelet-activating factor (PAF) antagonist, on pancreatitis-associated pulmonary injury in experimental acute pancreatitis. Material and methods. Acute pancreatitis was induced by intraductal infusion of 5% sod

Simple and accurate four-node axisymmetric element

Based on the assumed strain method, a simple four-node axisymmetric solid element is introduced. The assumed strain field is carefully selected to preserve the correct rank of the element stiffness matrix and to achieve high accuracy. The strain field is developed in conjunction with orthogonal projections and no matrix inversions are needed. The coarse mesh accuracy in bending and in typical axis

A cross-sectional analysis of physical activity and obesity indicators in European participants of the EPIC-PANACEA study

Objectives: Cross-sectional data suggest a strong association between low levels of physical activity and obesity. The EPIC-PANACEA ( European Prospective Investigation into Cancer-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating out of home And obesity) project was designed to investigate the associations between physical activity and body mass index (BMI) and waist circumferen

Factors affecting the clinical outcome after neural transplantation in Parkinson's disease

Intrastriatal grafts of embryonic mesencephalic tissue can survive in the brains of patients with Parkinson's disease, but the degree of symptomatic relief is highly variable and some cases develop troublesome dyskinesias. Here we explored, using clinical assessment and F-18-dopa and C-11-raclopride PET, factors which may influence the functional outcome after transplantation. We observed increase

Sources of variation in winter basal metabolic rate in the great tit

1. Basal metabolic rate (BMR) is the most widely used standard measurement of the cost of living. Despite the acknowledged phenotypic flexibility of BMR, little is known about the patterns of variation in wild animal populations. 2. We studied the sources of variation in BMR of great tit Parus major (L.) among individuals from two wild populations: Oulu (northern Finland) and Lund (southern Sweden

Scintigraphic method to quantify the passage from brain parenchyma to the deep cervical lymph nodes in rats

In order to investigate the kinetics of the passage from the brain parenchyma to the lymphatic system in vivo a high resolution scintillation camera technique was developed. Albumin, albumin colloids and dextran labelled with 99mTc were injected into the right side of the thalamus of anesthetized rats. Continuous measurement of the activity distribution in head and neck were performed for 70 min.

SuperScent--a database of flavors and scents

Volatiles are efficient mediators of chemical communication acting universally as attractant, repellent or warning signal in all kingdoms of life. Beside this broad impact volatiles have in nature, scents are also widely used in pharmaceutical, food and cosmetic industries, so the identification of new scents is of great industrial interest. Despite this importance as well as the vast number and d

Reduced training is associated with increased loss of BMD.

This 8-year controlled, follow-up study in 66 Swedish soccer women evaluated the effect of training and reduced training on BMD. The players who retired during the follow-up lost BMD in the femoral neck, whereas the controls did not. Introduction: Physical activity during adolescence increases BMD, but whether the benefits are retained with reduced activity is controversial. Materials and Method

Clinical utility of color-form naming in Alzheimer's disease: Preliminary evidence

Performances on Alzheimer's Quick Test color-form naming and Mini-Mental State Examination were compared for 38 adults with Alzheimer's disease and 38 age- and sex-matched normal controls. Group means differed significantly and indicated longer naming times by adults with Alzheimer's disease. The specificity for AQT color-form naming was 97% and sensitivity 97%, i.e., 3% false negatives. The speci

Exact solution of the Zeeman effect in single-electron systems

Contrary to popular belief, the Zeeman effect can be treated exactly in single-electron systems, for arbitrary magnetic field strengths, as long as the term quadratic in the magnetic field can be ignored. These formulas were actually derived already around 1927 by Darwin, using the classical picture of angular momentum, and presented in their proper quantum- mechanical form in 1933 by Bethe, altho

Integral equation methods for elliptic problems with boundary conditions of mixed type

Laplace’s equation with mixed boundary conditions, that is, Dirichlet conditions on parts of the boundary and Neumann conditions on the remaining contiguous parts, is solved on an interior planar domain using an integral equation method. Rapid execution and high accuracy is obtained by combining equations which are of Fredholm’s second kind with compact operators on almost the entire boundary with