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Pollen harvesting and reproductive rates in specialized solitary bees

Andrena humilis is an endangered oligolectic solitary bee and has declined in recent decades throughout western Europe. The aim of this study was to explore the pollen harvesting pattern and to determine the reproductive rate in specialized andrenid bees. We measured the amount of pollen required to produce one brood-cell, the pollen harvesting rate and compared our results with data for other spe

Proton MR spectroscopy and preoperative diagnostic accuracy: an evaluation of intracranial mass lesions characterized by stereotactic biopsy findings

BACKGROUND AND PURPOSE: MR imaging has made it easier to distinguish among the different types of intracranial mass lesions. Nevertheless, it is sometimes impossible to base a diagnosis solely on clinical and neuroradiologic findings, and, in these cases, biopsy must be performed. The purpose of this study was to evaluate the hypothesis that proton MR spectroscopy is able to improve preoperative d

Cornucopia or zero-sum game? The epistemology of sustainability

This article contrasts two fundamentally world-economy. The article begins by sketching different understandings of economic growth the history of these two perspectives in recent and “development” that lead to diametrically decades and reflecting on the ideological and opposed approaches to how to deal with epistemological contexts of their appearance global ecological deterioration. One is the a

Leukotriene B4 is the functional ligand binding to and activating the cloned chemoattractant receptor, CMKRL1

We recently described a novel chemoattractant receptor, provisionally named CMKRL1, which has turned out to be the first cloned leukotriene (LT) receptor. Present binding assays using tritiated LTB4 and isolated membranes from COS-7 cells, transiently transfected with cDNA encoding this receptor, yielded a linear Scatchard plot showing expression of only a single, high-affinity receptor population

WWTP dynamic disturbance modelling - an essential module for long-term benchmarking development

Intensive use of the benchmark simulation model No. 1 (BSM1), a protocol for objective comparison of the effectiveness of control strategies in biological nitrogen removal activated sludge plants, has also revealed a number of limitations. Preliminary definitions of the long-term benchmark simulation model No. 1 (BSM1_LT) and the benchmark simulation model No. 2 (BSM2) have been made to extend BSM

Sensitivity analysis via simulation in the presence of discontinuities

In this paper we address the problem of estimating the mean derivative when the entity containing the parameter has jumps. The methods considered are finite differences, infinitesimal perturbation analysis and the likelihood ratio score function. We calculate the difference between the differentiated mean and the mean derivative. In case of finite differences, we compute the stepsize in the simula

Viljen vi veta, viljen vi förstå ... : kunskapsbildning inom socialtjänsten

Denna rapport handlar om socialtjänstens kunskapsbildning. I dess inledning konstateras att kunskapsutveckling är något som ligger i tiden. Från flera håll pekas det på att det sker stora och viktiga insatser på detta område medan socialtjänsten av någon anledning tycks ha hamnat i skamvrån. I själva verket riktas det från flera oberoende håll stark kritik mot dess verksamhet och det hävdas att ar

High-intensity laser-driven proton acceleration: influence of pulse contrast

Proton acceleration from the interaction of ultra-short laser pulses with thin foil targets at intensities greater than 10(18) W cm(-2) is discussed. An overview of the physical processes giving rise to the generation of protons with multi-MeV energies, in well defined beams with excellent spatial quality, is presented. Specifically, the discussion centres on the influence of laser pulse contrast

The importance of age-related decline in forest NPP for modeling regional carbon balances

We show the implications of the commonly observed age-related decline in aboveground productivity of forests, and hence forest age structure, on the carbon dynamics of European forests in response to historical changes in environmental conditions. Size-dependent carbon allocation in trees to counteract increasing hydraulic resistance with, tree height has been hypothesized to be responsible for th

Transendothelial transport of low-density lipoprotein and albumin across the rat peritoneum in vivo: Effects of the transcytosis inhibitors NEM and filipin

This study was performed to investigate the mechanisms responsible for the transport of albumin and low-density lipoprotein (LDL) across capillary walls in vivo. To separate transcytosis from passive, 'porous' transport, we tested the effects of the transcytosis inhibitors N-ethylmaleimide (NEM) and filipin given intraperitoneally on the peritoneal capillary clearance of LDL and albumin in anesthe

Preoperative staging of rectal carcinoma using double-contrast MR imaging. Technical aspects and early clinical experiences

PURPOSE: To improve preoperative staging of rectal carcinoma with MR imaging, using a double-contrast technique. MATERIAL AND METHODS: Imaging was performed in 12 patients before and after i.v. injection of Gd-DTPA and rectal administration of a superparamagnetic contrast medium, mainly containing magnetite. The diagnostic information was evaluated and compared with findings at surgery and histopa

Long-term effects of Ca(2+) on structure and contractility of vascular smooth muscle

Culture of dispersed smooth muscle cells is known to cause rapid modulation from the contractile to the synthetic cellular phenotype. However, organ culture of smooth muscle tissue, with maintained extracellular matrix and cell-cell contacts, may facilitate maintenance of the contractile phenotype. To test the influence of culture conditions, structural, functional, and biochemical properties of r

Contractions induce phosphorylation of the AMPK site Ser(565) in hormone-sensitive lipase in muscle

Intramyocellular triglyceride is an important energy store which is related to insulin resistance. Mobilization of fatty acids from this pool is probably regulated by hormone-sensitive lipase (HSL), which has recently been shown to exist in muscle and to be activated by epinephrine via PKA and by contractions via PKC and ERK. 5' AMP-activated protein kinase (AMPK) is an intracellular fuel gauge wh