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Exopolyphosphatase/guanosine pentaphosphate phosphohydrolase (PPX/GPPA) enzymes play central roles in the bacterial stringent response induced by starvation. The high-resolution crystal structure of the putative Aquifex aeolicus PPX/GPPA phosphatase from the actin-like ATPase domain superfamily has been determined, providing the first insights to features of the common catalytic core of the PPX/GP

We examine the formation of vortices in a one- and two-component gas of bosonic atoms in a harmonic trap that is set rotating. Both the mean-field Gross-Pitaevskii approach, and the numerical diagonalization method are employed. For a two-component Bose gas, we show that beside the well-known coreless vortices of single quantization, the interatomic interactions between the two species may lead to

We have undertaken a number of experimental studies of the structure of singly ionized boron, B II. Much of this work was initially motivated by a search for the "missing" 2s3s S-1 term. There was a surprising disagreement between theory and experiment for this level. In this context lots of data for B II were collected over the years, from beam-foil experiments, high-resolution spark spectroscopy

This paper presents a new strategy for steam pressure control during web breaks in the paper machine. The aim was to restart paper production with the same drying properties of the cylinder as before the break. A detailed physical dynamic model of the drying cylinder has been developed. The accuracy of the model has been verified through experiments made at the M-real paper mill in Husum, Sweden.

Optimization of fed-batch conversion of lignocellulosic hydrolyzates by the yeast Saccharomyces cerevisiae was studied. The feed rate was controlled using a step response strategy, in which the carbon dioxide evolution rate was used as input variable. The performance of the control strategy was examined using both an untreated and a detoxified dilute acid hydrolyzate, and the performance was compa

OBJECTIVE: The authors synthesize findings of previous studies implicating migration as a risk factor for the development of schizophrenia and provide a quantitative index of the associated effect size. METHOD: MEDLINE was searched for population-based incidence studies concerning migrants in English-language publications appearing between the years 1977 and 2003. Article bibliographies and an Aus

The objective was to elucidate hemodynamic adaptation in very low birth weight (<1500 g) infants after intrauterine growth retardation. 31 growth-retarded (SGA, birth weight <-2 SD) and 32 appropriate for gestational age (AGA, birth weight within +/- 1 SD range) infants were enrolled. In SGA infants, the diastolic diameters of the interventricular septum and the left ventricle were increased, and

An hypothesis is presented that provitamin D (dehydrocholesterol and/or ergosterol) can act as a UV-B receptor in plants and algae. We also propose that the proportions between provitamins D, previtamins D, and vitamins D (D2 and D3), after calibration, can be used to evaluate UV-B exposure of phytoplankton and terrestrial vegetation. This is the final, accepted and revised manuscript of this art

In our previous papers polyethylene degradation during extrusion coating has been studied and the type of degradation products that are formed and from which step they originate have been discussed. A trained sensory panel has rated the off-flavor intensities in water samples that have been in contact with various extruded films. Encouraged by the results from these investigations and the document

Archaeologists have often felt uneasy when encountering alternative (fringe, cult, fantastic, pseudo-) archaeologies. Some have suggested that alternative approaches and their results must be disproved, while others have been calling for better public understanding of science. My contribution takes a different point of view. I emphasize the social and cultural needs that both scientific and altern

During recent decades, concern about the loss of biodiversity on agricultural land has increased, and semi-natural grasslands have been highlighted as critical habitats. Temperate European agricultural landscapes require distinct and appropriate management to prevent further impoverishment of the flora and fauna. This is especially urgent for pollinating insects that provide important ecosystem se

We study the problem of pricing barrier options and Russian options driven by exponential NIG Levy processes by simulation. Simulating at a discrete grid creates a systematic bias because the minimum and maximum in between grid points is neglected. The proposed solution is to simulate the large jumps only and use a Brownian approximation for the rest combined with explicit formulas for Brownian mi

The thermoseparation of aqueous solutions of Breox 50 A 1000, an ethylene oxide-propylene oxide 50:50 (w/w) random copolymer, was studied. The cloud-point diagram for Breox in water solution and the effects of electrolytes and surfactants on the cloud-point temperature (CPT) were determined. The Breox concentration in both phases after the thermoseparation was followed with a reversed-phase HPLC m

Recent studies in mouse models deficient in transforming growth factor beta (TGF-beta) signaling have documented TGF-beta as one of the major regulators of immune function. TGF-beta1-null animals demonstrated massive autoimmune inflammation affecting multiple organs, but attempts to transfer the phenotype to normal animals by bone marrow transplantation only resulted in minor inflammatory lesions.

Faeces were collected from 60 cows at three slaughterhouses situated in southern and central Sweden. The faecal samples were collected during two sampling periods over the year, summer and winter. All samples were analysed for the presence of Clostridium botulinum spores, according to a combined selection and enrichment PCR procedure. One PCR assay was specific for part of the type B neurotoxin ge

The phylogenetic relationships within the fungus gnat tribe Exechiini have been left unattended for many years. Recent studies have not shed much light on the intergeneric relationship within the tribe. Here the first attempt to resolve the phylogeny of the tribe Exechiini using molecular markers is presented. The nuclear 18S and the mitochondrial 16S, and cytochrome oxidase subunit I (COI) genes

The association of fruit and vegetable consumption and lung cancer incidence was evaluated using the most recent data from the European Prospective Investigation into Cancer and Nutrition (EPIC), applying a refined statistical approach (calibration) to account for measurement error potentially introduced by using food frequency questionnaire data. Between 1992 and 2000, detailed information on die

The aim of the study was to investigate the relation between the phenomenological quality of memory (Tulving, 1985) and the realism (validity) in confidence judgement when using emotional pictures (I.A.P.S; Lang, Ohman, & Vaitl, 1988). A series of three experiments was completed where the participants judged the phenomenological quality of their memory and/or their confidence. The results show