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A range of observations points towards earlier onset of spring in northern high latitudes. However, despite the profound effects this may have on vegetation-atmosphere exchange of carbon (NEE), vegetation-atmosphere physical coupling, or the location of the tundra-taiga interface, the number of studies that investigate winter-spring transition fluxes in contrasting northern vegetation types is lim

Electronic factors influencing the photoluminescence properties and rates of excited state intramolecular proton transfer (ESIPT) reaction of o-hydroxy derivatives of 2,5-diphenyl-1,3,4-oxadiazole have been studied. The potential of these molecules as emissive and electron transport materials in designing improved organic light emitting diodes (OLEDs) has been studied by analyzing possible reasons

Results on transverse mass spectra of neutral pious measured at central rapidity are presented for impact parameter selected 158-A GeV Pb + Pb-1 and Pb + Nb collisions. The distributions cover the range 0.5 GeV/c(2) less than or equal to MT - Mo less than or equal to 4 GeV/c(2). The change of the spectral shape and the multiplicity with centrality is studied in detail. In going from p+p to semi-pe

A Swedish cooperative trial demonstrated that 5 years of adjuvant tamoxifen was more beneficial than 2 years of tamoxifen in the treatment of postmenopausal women with estrogen receptor (ER) positive, early stage, invasive breast cancer. The main aim of the present study was to investigate the importance of progesterone receptor (PgR) and ER concentration levels for patients participating in the t

To study the individual variation in chylomicron clearance rate, young healthy volunteers were given a p.o. dose of 50,000 IU retinyl palmitate in the morning to label their chylomicrons. Serial blood samples were then obtained in the time interval 4-8 h after retinyl palmitate intake, to closely monitor the clearance of retinyl ester from the blood. The procedure was repeated in an identical way

The conditions behind sudden approximation are critically examined. The fuzzy band expression is derived in detail from first principles. We go beyond the sudden approximation to account for both extrinsic losses and interference effects. In an extension of earlier work we discuss both core and valence satellites including both intrinsic and extrinsic amplitudes, and high energy excitations as wel

Random PCR mutagenesis was applied to the Thermus thermophilus xylA gene encoding xylose isomerase. Three cold-adapted mutants were isolated with the following amino-acid substitutions: E372G, V379A (M-1021), E372G, F163L (M-1024) and E372G (M-1026). The wild-type and mutated xylA genes were cloned and expressed in Escherichia coli HB101 using the vector pGEM-T Easy, and their physicochemical and

It is well known that the effects of direct (lethal) predator-prey interactions propagate through food webs (the trophic cascade). However, in the present study we show for the first time that, parallel to the trophic cascade, there exists a behavioral cascade in the sense that behavioral responses, induced by the nonlethal presence of a top predator, are transmitted down the food chain over more

Previous time series evidence has indicated that farmland prices and cash rents are not cointegrated, a finding at odds with the present value model of farmland prices. We argue that this failure to find cointegration may be due to low power of tests and to the presence of structural change representing a shifting risk premium on farmland investments. To accommodate this possibility, we use panel

The objective of this investigation was to study regional absorption of inhaled insulin together with an enhancer (sodium di-octyl-sulfosuccinate [DOSS]) in the rabbit airways and lung. Insulin was administered with or without DOSS by aerosol inhalation, intratracheal infusion, intranasally, sublingually, and without DOSS intravenously. Blood glucose and plasma levels of insulin were measured duri