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Spectroscopic studies of aluminum and gallium complexes with oxalate and malonate in aqueous solution

The local structures of Ga(III) in aqueous oxalate and malonate complexes were studied by means of Ga K-edge EXAFS spectroscopy. Irrespective of the number and type of coordinated ligands, the EXAFS results showed very regular first coordination shells consisting of six oxygen atoms. Scattering paths from more distant atoms revealed that both oxalate and malonate form mononuclear chelate structure

Avian orientation at steep angles of inclination: experiments with migratory white-crowned sparrows at the magnetic North Pole

The Earths magnetic field and celestial cues provide animals with compass information during migration.Inherited magnetic compass courses are selected based on the angle of inclination, making itdifficult to orient in the near vertical fields found at high geomagnetic latitudes. Orientation cage experimentswere performed at different sites in high Arctic Canada with adult and young white-crownedsp

A precise measurement of the tau lifetime

The tau lepton lifetime has been measured with the e(+) e(-) --> tau(+) tau(-) events collected by the DELPHI detector at LEP in the years 1991 - 1995. Three different methods have been exploited, using both one-prong and three-prong tau decay channels. Two measurements have been made using events in which both taus decay to a single charged particle. Combining these measurements gave tau(tau) ( 1

Conformational fluctuations and large fluorescence spectral diffusion in conjugated polymer single chains at low temperatures

The fluorescence of single chains of the conductive polymer poly [2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) was studied by means of single-molecule spectroscopy at 15 K. MEH-PPV was deposited onto a surface from a toluene solution and covered with a polymer cap layer of poly(vinyl alcohol) spin-coated from an aqueous solution for protection against air. Because MEH-PPV is in

The mechanical properties of elastic arteries in Ehlers-Danlos syndrome

OBJECTIVE: To study whether measurements of wall mechanics can be used as an indicator of disturbed vessel wall integrity and predictor of vessel fragility in Ehlers-Danlos Syndrome (EDS). METHODS: The wall mechanics of the abdominal aorta (AO) and common carotid artery (CCA) were estimated from the indices Ep (pressure strain elastic modulus) and stiffness (beta) in twelve individuals with EDS of

Demonstration of correlations between clinical and physical image quality measures in chest and lumbar spine screen-film radiography

The ability to predict clinical image quality from physical measures is useful for optimization in diagnostic radiology. In this work, clinical and physical assessments of image quality are compared and correlations between the two are derived. Clinical assessment has been made by a group of expert radiologists who evaluated fulfillment of the European image criteria for chest and lumbar spine rad

The Free Fatty Acid Receptor GPR40 - expression and role in islet hormone secretion

Type 2 diabetes (T2D) is a serious condition of growing proportions. Developing via an increasing imbalance between insulin sensitivity in the peripheral tissues and insulin release from pancreatic beta-cells, it ultimately renders the individual incapable of regulating the blood glucose concentration, e.g. after a meal. The increased prevalence of T2D is associated with an increase in the prevale

Prey size selection in piscivorous pikeperch (Stizostedion lucioperca) includes active prey choice

Knowledge of the mechanisms behind prey selection in piscivorous fish is important for our understanding of the dynamics of freshwater systems. Prey selection can involve active predator choice or be a passive process. We experimentally studied size-selectivity in pikeperch, feeding on roach and rudd. When given a choice of different prey sizes, pikeperch selected small prey. Passive selection mec

The temperature influences the ratio of glucosidase and galactosidase activities of beta-glycosidases

The selectivity for the glycon part of a donor substrate of beta-glycosidases from almond, a mesophilic (Kluyveromyces fragilis) and three highly thermophilic organisms (Caldocellum saccharolyticum, Sulfolobus solfataricus and Pyrococcus furiosus) was investigated at various temperatures (25-90 degreesC ). On the basis of kinetic constants, the selectivity was calculated as the specificity constan

Regulation of angiogenesis by tissue factor cytoplasmic domain signaling

Hemostasis initiates angiogenesis-dependent wound healing, and thrombosis is frequently associated with advanced cancer. Although activation of coagulation generates potent regulators of angiogenesis, little is known about how this pathway supports angiogenesis in vivo. Here we show that the tissue factor (TF)-VIIa protease complex, independent of triggering coagulation, can promote tumor and deve