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Life history consequences of fixed costs of reproduction

The distinction between fixed and variable factors of production and their corresponding costs has: long played a fundamental role in economic theory. However, in analyses of life history evolution a distinction between fixed and variable costs of reproduction has not been made. In this paper. I discuss these concepts and analyze some effects of fixed costs of reproduction on reproductive decision

Gene expression profiling in single cells from the pancreatic islets of Langerhans reveals lognormal distribution of mRNA levels.

The transcriptional machinery in individual cells is controlled by a relatively small number of molecules, which may result in stochastic behavior in gene activity. Because of technical limitations in current collection and recording methods, most gene expression measurements are carried out on populations of cells and therefore reflect average mRNA levels. The variability of the transcript levels

Flexible Embedded Control Systems : Design and Implementation

Embedded control system design is a complex and error prone task, and there is a great need for better development tools. Today most real-time control systems are static systems, designed in an ad-hoc fashion. A more interactive way of working would give shorter development times, reduced costs for testing, and safer, more robust systems. This thesis presents an interactive prototyping tool called

Mat och levnadskonst : Arkiater Linné ger råd

The art of living and the art of eating: Professor Linnaeus recommends. By Gunnar Broberg. As professor of medicine, Linnaeus taught dietetics. He followed the pattern outlined by Galen and Regimen salernitatis, adding an extensive material originating from general cultural history and his own experience.Early in his life he wrote Diaeta naturalis, a collection of rules focusing the blessings of n

Comparison of the proximal promoter regions of the PAX3 and PAX7 genes

Translocations t(2;13)(q35;q14) and t(1;13)(p36;q14), which fuse PAX3 and PAX7, respectively, to FOXO1A, characterize alveolar rhabdomyosarcoma. Previous studies have suggested that the expression of PAX7-FOXO1A is copy-number dependent, but that of PAX3-FOXO1A is not, which may be due to a weaker PAX7 than PAX3 promoter. The aim of the present study was to compare the transcriptional activities o

Non-invasive assessment of magnitude and dispersion of atrial cycle length during chronic atrial fibrillation in man

AIMS: Atrial fibrillation cycle lengths can be assessed from right precordial ECG leads and the unipolar oesophageal ECG using a non-invasive method called Frequency Analysis of Fibrillatory ECG. The purpose of this report is to present the results from application of this method in a large group of patients with long-term atrial fibrillation and to examine the differences between patients with 'c

Ten-year risk of osteoporotic fracture and the effect of risk factors on screening strategies

Bone mineral density (BMD) measurements are widely used to estimate the risk of osteoporotic fractures. In addition, many other risk factors have been identified, sonic of which are known to add to the risk independently of BMD measurements. The combination of BMD with such risk factors increases the gradient of risk/standard deviation (SD) than that achieved by BMD alone. In this paper, we report

A study of the functionalities of the phases in Mo-V-Nb-Te oxides for propane ammoxidation

Catalysts belonging to the Mo-V-Nb-Te-O system have been prepared with both a slurry method and hydrothermal synthesis and were tested for propane and propylene ammoxidation to acrylonitrile. All samples were characterized with BET, XRD, ICP and XPS. The catalysts were found to consist of three phases, to which activity and selectivity correlations were made. The results indicate that both an orth

Decreased levels of ionized calcium one year after hemithyroidectomy: importance of reduced thyroid hormones

BACKGROUND: Previously we have found reduced levels of total serum calcium and 1,25(OH)2D3 despite an unaltered stimulated parathyroid hormone (PTH) secretion 1 year after hemithyroidectomy. The present study was undertaken to elucidate the possible relationship between calcium homeostasis, thyroid hormones and bone resorption in a group of 45 consecutive patients subjected to hemithyroidectomy be

Physical and Chemical Characterisation of Potassium Deactivation of an SCR Catalyst for Biomass Combustion

The deactivation of a commercial Selective Catalytic Reduction (SCR) catalyst, of V2O5−WO3/TiO2 type, has been studied through comparisons with results from a full-scale biomass combustion plant to that with laboratory experiments. In the latter, the catalyst was exposed to KCl and K2SO4 by both wet impregnation with diluted salt solutions and deposition of generated submicrometer aerosol particle

Environmental influence on recovery after brain lesions--experimental and clinical data.

One aim of rehabilitation after brain lesions should be to optimise the function of the remaining intact brain. Experimental studies on focal cerebral infarcts in the rat have demonstrated that postischemic environmental enrichment significantly improves functional outcome, increases dendrite branching and number of dendritic spines in the contralateral cortex, influences expression of many genes

Fogar i träfönster : förstudie

Studien utgör underlag till en konstruktionslära för fogar i fönster. I rapporten pekas på problem med att upprätthålla fuktbalans i fönsterträ då fukt kapillärt sugs in via konstruktionens diskontinuiteter. Inledande försök beskrivs liksom förslag till åtgärder i befintliga fönster.

Was southern Sweden ice free at 19-25 ka, or were the post LGM glacifluvial sediments incompletely bleached?

Glacifluvial deposits along an ice-marginal zone,in Smaland, southern Sweden, have been dated using post-IR blue OSL. To test for incomplete bleaching, we adopted two strategies: analysis of modern analogues and small-aliquot dose distributions. Samples of modern fluvial sediments show no significant incomplete bleaching; they yield equivalent doses of only 0.5-2 Gy (similar to 0.25-4% of our glac

Xenotransplantation public perceptions: rather cells than organs.

The aim of this study was to describe some of the factors that might play a role in influencing attitude to xenotransplantation: first, the consideration of receiving cells and tissue from xenotransplants in relation to whole xeno-organs; secondly, the fact that there is greater uncertainty regarding the result and risk of infection associated with xenotransplantation than with allotransplantation