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Evidence for nontermination of rotational bands in Kr-74

Three rotational bands in Kr-74 were studied up to (in one case one transition short of) the maximum spin I-max of their respective single-particle configurations. Their lifetimes have been determined using the Doppler-shift attenuation method. The deduced transition quadrupole moments reveal a modest decrease, but far from a complete loss of collectivity at the maximum spin I-max. This feature, t

Genetic factors related to racial variation in plasma levels of insulin-like growth factor-1: implications for premenopausal breast cancer risk

The oral contraceptive pill is associated with a modest increase in the risk of early-onset breast cancer in the general population, but it is possible that the risk is higher in certain subgroups of women. The relative risk of breast cancer associated with oral contraceptive use has been reported to be higher for African-American women than for white women. African-American women also have a high

Relative risks and effective number of meioses: A unified approach for general genetic models and phenotypes

Many common diseases are known to have genetic components, but since they are non-Mendelian, i.e. a large number of genetic factors affect the phenotype, these components are difficult to localize. These traits are often called complex and analysis of siblings is a valuable tool for mapping them. It has been shown that the power of the affected relative pairs method to detect linkage of a disease

Aqueous phase behavior of hexaethylene glycol dodecyl ether studied by differential scanning calorimetry, Fourier transform infrared spectroscopy, and C-13 NMR spectroscopy

The phase behavior of aqueous mixtures of a nonionic surfactant, hexaethylene glycol dodecyl ether (C12E6), was investigated by means of differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, and C-13 nuclear magnetic resonance (C-13 NMR) spectroscopy, The T-X phase diagram of this system was constructed from the DSC results. Comparison of the phase diagram with

Wing wear, aerodynamics and flight energetics in bumblebees (Bombus terrestris): an experimental study

I. Previous work has shown that wing wear increases mortality rate in bumblebees. Two proximate explanations have been suggested to account for this: increased energy flight costs and increased predation risk due to reduced manoeuvrability. 2. Wing wear was mimicked by experimentally clipping the forewing distal trailing edge, causing a 10% wing area reduction. Experimental and sham control bumble

Temporally fluctuating prey and coexistence among unequal conspecific interferers

Coexistence among unequal conspecific interferers should be unlikely to persist if stronger interferers always experience a relative fitness increment from their higher foraging rates. In this study, we suggest that decreased relative costs to weaker interferers with increasing temporal fluctuations in prey availability may be a mechanism enhancing coexistence of unequal conspecific interferers. P

Origin and evolution of the mitochondrial proteome

The endosymbiotic theory for the origin of mitochondria requires substantial modification. The three identifiable ancestral sources to the proteome of mitochondria are proteins descended from the ancestral alpha -proteobacteria symbiont, proteins with no homology to bacterial orthologs, and diverse proteins with bacterial affinities not derived from alpha -proteobacteria. Random mutations in the f

Effects of Alzheimer's peptide and alpha 1-antichymotrypsin on astrocyte gene expression

We employed gene array technology to investigate the effects of alpha 1-antichymotrypsin (ACT), soluble or fibrillar Alzheimer's peptide (A beta(1-42)) alone and the combination of ACT/A beta(1-42) on human astrocytes. Using a 1.2-fold change as significance threshold, 398 astrocyte genes showed altered expression in response to these treatments compared to controls. Of the 276 genes affected by t

Conodont-based revisions of the late Ludfordian on Gotland, Sweden

The Late Ludlow topmost Hemse-Burgsvik succession includes more substantial and more rapid facies changes than most older and younger intervals on Gotland. A revised conodont zonation for this interval includes three zones, the Polygnathoides siluricus, the Icriodontid, and the Ozarkodina snajdri zones and four subzones, the Upper P. siluricus, the Lower, the Middle and the Upper Icriodonfid subzo

An acyl-CoA:cholesterol acyltransferase (ACAT)-related gene is involved in the accumulation of triacylglycerols in Saccharomyces cerevisiae

The major route for the synthesis of triacylglycerol (TAG) in yeast as well as in all TAG-accumulating organisms has been suggested to occur via the acylation of diacylglycerol (DAG) by acyl-CoA:diacylglycerol acyltransferase (DAGAT). Genes encoding DAGAT have been identified in both plant and animal tissues. These genes show strong sequence similarities to genes encoding acyl-CoA:cholesterol acyl