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Structural integrity of prestressed nuclear reactor containments

Popular Abstract in Swedish Ett kärnkraftverk är utrustat med ett omfattande försvar avsett att förhindra radioaktivt utsläpp vid en eventuell reaktorolycka. Detta försvar är uppbyggt av ett antal skyddsbarriärer, där reaktorinneslutningen utgör den sista barriären mot omgivningen. Inneslutningens primära uppgift är att motstå det inre övertryck som kan förväntas vid en reaktorolycka. Alla svenskaA nuclear power plant is provided with an extensive defense intended to prevent radioactive discharge in case of a reactor accident. This defense is built up of several independent safety barriers, where the reactor containment constitutes the last barrier to the environment. The fundamental safety function of the containment is to withstand the internal pressure expected in the event of an accide

Developmental history of the Glover-Nilsson smoking behavioral questionnaire

Objective: To develop a simple, easily administered pencil-and-paper questionnaire to determine the degree to which behavioral patterns play a role in smoking dependence. Methods: A modified Delphi technique was used to identify initial questions and to eliminate obvious duplications. Phase 2 utilized multiple statistical methods (principal components analysis, cluster analysis, stepwise multiple

GIS-hydrological modelling in arid lands : a geographical synthesis of surface waters for the African Red Sea region in the Sudan

Popular Abstract in Swedish Forskning och studier av ytvattensystem i sudanesiska röda havsområdet för utveckling av relevant metodik medför ett antal konceptuella svårigheter. Ett huvudsakligt problem är den begränsade tillgången till litteratur och mätdata för modellutveckling. En annan svårighet är tillämpligheten av redan existerande metoder och modeller utvecklade i andra regioner. För att bThe magnitude and availability of surface waters in the arid/semi-arid Sudanese Red Sea region has been examined. In conjunction with the research objective, opinions and methodologies applied by previous researchers have been assessed. The study applied a geographical hydrological synthesis within a GIS framework. As a system with advanced geo-modelling capabilities, GIS is used to integrate spat

Extracellular ATP: a growth factor for vascular smooth muscle cells

1. Extracellular adenosine triphosphate (ATP) is mitogenic for vascular smooth muscle cells (VSMC) and stimulates several events that are important for cell proliferation: DNA synthesis, protein synthesis, increase of cell number, immediate early genes, cell-cycle progression, and tyrosine phosphorylation. 2. Receptor characterization indicates mitogenic effects of both P2U and P2Y receptors. The

On radial solutions of certain semi-linear elliptic equations

We consider the semi-linear elliptic equation Delta u + f (x, u) + g (vertical bar x vertical bar)x center dot del u = 0, in some exterior region of R-n, n >= 3. It is shown that if f depends radially on its first argument and is nonincreasing in its second, boundary conditions force the unique solution to be radial. Under different conditions, we prove the existence of a positive radial asymptoti

The pre-fysch and basal shaly flysch deposition in the Parnassus-Ghiona Zone, central Greece

The interruption in deposition during the K/T transition in the Parnassus-Ghiona Zone caused the formation of hardgrounds and intraformational conglomerates in the central parts. During the later part of the early Paleocene to the middle or early part of the late Paleocene a shallow sea covered central Parnassus; stromatolites formed in broad valleys and phosphatic calcarenitic accumulations in sm

Failure of the vapor-liquid-solid mechanism in Au-assisted MOVPE growth of InAs nanowires

We report the temperature dependence of the Au-assisted growth of InAs nanowires in MOVPE. Extensive studies of the growth of such nanowires have attributed growth to the so-called vapor-liquid-solid (VLS) mechanism, with a liquid Au-In alloy particle. We assert here that growth is instead assisted by a solid particle and does not occur at all when the particle is a liquid. Thus the temperature ra

Effect of hypoxia on the tumor phenotype: the neuroblastoma and breast cancer models

The tumor oxygenation status associates with aggressive behavior. Oxygen shortage, hypoxia, is a major driving force behind tumor vascularization, and hypoxia enhances mutational rate, metastatic spread, and resistance to radiation and chemotherapy. We recently discovered that hypoxia promotes dedifferentiation of neuroblastoma and breast carcinoma cells and development of stem cell-like features.

Towards an integrated ecology through mechanistic modelling of ecosystem structure and functioning

Popular Abstract in Swedish Traditionellt har olika aspekter av ett ekosystem studerats var för sig inom olika ekologiska discipliner såsom växtfysiologi, forskning om hur organismer interagerar med varandra och forskning om hur ekosystem som helhet beter sig. Denna avhandling innehåller exempel på att simulationsmodeller gör det möjligt att undersöka hur de olika processerna samverkar för att forPlant physiology, population dynamics and the structure and functioning of ecosystems are closely interrelated. However, these processes are often investigated independently within different subdisciplines of ecology. Mechanistic models of ecosystem structure and functioning combine representations of processes operating at a range of scales and levels of organisation, providing a tool for the des

Targeting proteins to secretory lysosomes of natural killer cells as a principle for immunoregulation.

Secretory lysosomes of natural killer (NK) cells combine storage, regulated secretion and lysosomal activity. We asked whether one could target exogenous proteins to the secretory lysosomes of NK-cells for final delivery into a tumor site upon degranulation. cDNAs for both soluble and transmembrane (tm) proteins were expressed in the human YT-Indy NK-cell line. Targeting of a soluble TNF receptor

The common identity of five glycosidases in human liver

An enzyme has been isolated from human liver by DEAE-cellulose chromatography and has been shown by competitive substrate inhibition to be capable of hydrolysing synthetic beta-D-galactosides, beta-D-glucosides, beta-D-fucosides, beta-D-xylosides, and alpha-L-arabinosides. Another form of alpha-L-arabinosidase activity elutes with the major beta-D-galactosidase component on DEAE-chromatography, bu

From major amputation to prosthetic outcome: A prospective study of 190 patients in a defined population that underwent major amputation

In this prospective study, the overall treatment and outcome of patients that underwent major lower limb amputation in a defined population is described. The study was performed over a five year period in the Health Care District of North-East Skåne, Sweden. Some 190 patients, permanent inhabitants of the Health Care District, underwent major lower limb amputation. Sixteen (16) of these patients h

Toxicity in Peridinium aciculiferum - an adaptive strategy to outcompete other winter phytoplankton?

Freshwater dinoflagellates may form dense blooms during winter in ice-covered lakes. Unlike their marine counterparts, freshwater dinoflagellates are rarely considered to be potential toxin producers. Here we tested whether the winter species Peridinium aciculiferum produces a toxin(s) and investigated the potential adaptive function of that toxin, i.e., predator defense or inhibition of competito

Coupling between lateral modes in a vertical resonant tunneling structure

We present experimental results and theoretical calculations of the vertical electron transport through a laterally constricted resonant tunneling transistor. Current-voltage measurements at 4.2 K show numerous current peaks that exhibit a complex dependence on the applied gate voltage. A scattering-matrix approach combined with the Landauer formalism was used to perform quantum mechanical calcula

Experimental analysis of local flame extinction in a turbulent jet diffusion flame by high repetition 2-D laser techniques and multi-scalar measurements

In this paper, we present a detailed experimental study of turbulence chemistry interactions in the "DLR_B" turbulent jet diffusion flame. The flame operates on mixtures of CH4, H-2, and N-2 in the fuel stream at Re = 22,800 and is a target flame within the TNF workshop. Extinction and re-ignition events can be tracked in real time and related to the underlying flow field phenomena and temperature