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Long-term manipulation of the microbes and microfauna of two subarctic heaths by addition of fungicide, bactericide, carbon and fertilizer

Nutrient availability is a major constraint to plant production and carbon storage in arctic ecosystems, but there are few studies coupling processes in the decomposer and microbial food web and the implications these processes have on the control of nutrient mineralization. We studied the relationship between microbial biomass and the abundance of microbivore and the role of grazing on nutrient t

A review of the production of ethanol from softwood

Ethanol produced from various lignocellulosic materials such as wood, agricultural and forest residues has the potential to be a valuable substitute for, or complement to, gasoline. One of the major resources in the Northern hemisphere is softwood. This paper reviews the current status of the technology for ethanol production from softwood, with focus on hemicellulose and cellulose hydrolysis, whi

Nitric oxide independent activation of guanylate cyclase by YC-1 causes erectile responses in the rat.

PURPOSE: Activation of soluble guanylate cyclase with a subsequent increase in intracellular levels of cyclic guanosine monophosphate is necessary for normal erection. In vascular tissue 3(5'-hydroxymethyl-2'-furyl-1-benzyl indazole (YC-1) (Abbott Laboratories, North Chicago, Illinois) has been shown to stimulate soluble guanylate cyclase independent of nitric oxide. We studied whether YC-1 modula

Extraction of plasmid DNA from Escherichia coli cell lysate in a thermoseparating aqueous two-phase system

The primary purification of a 6.1kilo base pair (kbp) plasmid from a desalted alkaline lysate has been accomplished by a thermoseparating aqueous two-phase system [(50% ethylene oxide-50% propylene oxide)-Dextran T 500]. The partitioning of the different nucleic acids (plasmid DNA, RNA, genomic DNA) in the thermoseparating aqueous two-phase system was followed both qualitatively by agarose gel ele

Effect of surface grafted polymers on the adsorption of different model proteins

Adsorption of a model protein to a surface with end-grafted polymers was studied by Monte Carlo simulations. In the model the effect on protein adsorption in the presence of end-grafted polymers was evaluated by calculating the change in free energy between an end-grafted surface and a surface without polymers. The change in free energy was calculated using statistical mechanical perturbation theo

Sphingosine 1-phosphate antagonizes human neutrophil apoptosis via p38 mitogen-activated protein kinase.

Sphingosine 1-phosphate (SPP) is associated with the regulation of apoptosis, although its role in neutrophil apoptosis remains poorly investigated. Here, we show that exogenous SPP antagonizes spontaneous and anti-Fas-induced apoptosis in neutrophils. Pre-treatment with pertussis toxin clearly reduced the apoptosis-inhibiting capacity of SPP. Consequently, we investigated the involvement of poten

GDH biosensor based off-line capillary immunoassay for alkylphenols and their ethoxylates

The application of a quinoprotein glucose dehydrogenase modified thick-film sensor as label detector in a capillary immunoassay (CIA) for xenoestrogens is presented. The detection of the alkylphenols and their ethoxylates is based on the competition between the analyte and tracer molecules for the binding sites of anti-alkylphenol ethoxylate antibodies. This assay is performed off-line in small di

PLASMA PROTEINS IN NORMAL AND PREECLAMPTIC PREGNANCY

Popular Abstract in Swedish Havandeskapsförgiftning (preeklampsi) är ett allvarligt risktillstånd som uppkommer vid 1.5-2.0 % av alla graviditeter och sjukdomen är en av de största orsakerna till mödra- och barndödlighet i världen. Preeklampsi karaktäriseras av högt blodtryck och läckage av äggvita i urinen under sista hälften av graviditeten hos en tidigare frisk kvinna. Njurarna spelar en avgöraThe aim of the research presented in this thesis was to provide extended background knowledge concerning several biochemical markers, used for the medical evaluation of pregnant women with suspected or confirmed preeclampsia, in order to improve the reliability of monitoring. Plasma levels of beta-2 microglobulin, cystatin C and beta trace protein are known to reflect renal filtration in non-pregn

Novel method to prepare morphologically rich polymeric surfaces for biomedical applications via phase separation and arrest of microgel particles

We outline here a simple method to prepare polymeric surfaces of controlled surface topography on the micrometer scale, via assembly and arrest of microgel particles, for use in a range of biological applications to modify cell adhesion and spreading. In previous work by other groups, it has transpired that topography on the nanoscale is unlikely to be useful for this purpose, as roughness on this

Computational Analysis of Gas Flow and Heat Transport Phenomena in Ducts Relevant for Fuel Cells

The thesis concerns modeling, simulation and numerical analysis of heat and mass transport, and fluid flow in ducts of both solid oxide fuel cells (SOFCs) and proton exchange membrane fuel cells (PEMFCs). The unique fuel cell boundary conditions (thermal, mass) for the flow ducts in fuel cells are identified and applied. Various duct configurations have been studied, such as rectangular and trapez

Selective modulation of protein C affinity for EPCR and phospholipids by Gla domain mutation

Uniquely amongst vitamin K-dependent coagulation proteins, protein C interacts via its Gla domain both with a receptor, the endothelial cell protein C receptor (EPCR), and with phospholipids. We have studied naturally occurring and recombinant protein C Gla domain variants for soluble (s)EPCR binding, cell surface activation to activated protein C (APC) by the thrombin-thrombomodulin complex, and

SOC Test Time Minimization Under Multiple Constraints

In this paper, we propose a SOC (system-on-chip) test scheduling technique that minimizes the test application time while considering test power limitations and test conflicts. The test power consumption is important to consider since exceeding the system's power limit might damage the system. Our technique takes also into account test conflicts that are due to cross-core testing (testing of inter

Hericenols A-D and a chromanone from submerged cultures of a Stereum species

Extracts of submerged cultures of a Stereum species afforded four new pentasubstituted phenolic compounds, named hericenols A, B, C, and D (1-4), 6-hydroxymethyl-2,2-dimethylchroman-4-one (5) and the known erinapyrone C. Hericenol A (1) showed weak antimicrobial activity while hericenol C (3) was weakly cytotoxic. The structures of the metabolites were determined by spectroscopic techniques. (C) 2

Thermomechanical response of non-local porous material

A thermomechanical model of a porous material is presented. The constitutive model is based on the Gurson model, formulated within a thermodynamic framework and adapted to large deformations. The thermodynamic framework yields a heat equation that naturally includes the mechanical dissipation. To introduce a length scale, the Gurson model was enhanced through non-local effects of the porosity bein

En bildpedagogisk studie : lärare undervisar och elever gör bilder

Popular Abstract in Swedish Bildundervisningen i grundskolans tidigare år uppfyller inte de i Sverige uppsatta målen. De nationella utvärderingarna (NU 89) och (NU92) bekräftar detta. Lärarna säger att de saknar ämneskunskaper och utvärderingarna visar att inslag från äldre läroplaner präglar undervisningen. För att ge en bild av hur nuvarande problem kan ha uppstått presenteras i studien en histoThe art education in Swedish primary and secondary schools is far from perfect and as a result pupils seldom reach the desired standard. National evaluations in 1989 and 1992 confirm this. Teachers admit that they lack specific subject knowledge and evaluation reveals that many aspects of older curricula still prevail. The way in which the present problems may have arisen is described through the