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Zircon geochronology in polymetamorphic gneisses in the Sveconorwegian orogen, SW Sweden: ion microprobe evidence for 1.46-1.42 and 0.98-0.96 Ga reworking

Ion microprobe U-Th-Pb analyses of zircons in variably metamorphosed and veined orthogneisses in the southern part of the parautochthonous Eastern Segment of the Sveconorwegian (1.20-0.90 Ga) orogen, SW Sweden, broadly define two age groups, oscillatory and sector zoned magmatic zircon cores yield 1.70-1.68 Ga while overgrowths, homogeneous crystals, and recrystallized domains in primary zircon yi

Corticosteroid action on choroid plexus: reduction in Na+-K+-ATPase activity, choline transport capacity, and rate of CSF formation

Glucocorticoids have a well-known clinical effect on brain edema and intracranial hypertension, but the mechanism of action is still poorly understood. In the present report the effect of beta-methasone on choroid plexus transport and CSF formation was studied. Following 5 days of daily treatment with betamethasone the CSF production rate in rabbits was reduced by 43% as measured by ventriculo-cis

Helicobacter pylori antibodies and gastric cancer: a gender-related difference

Helicobacter pylori has been proposed as a causative agent of gastric cancer. The aim of this study was to define serum antibodies response against different H. pylori antigens in patients with gastric cancer. Serum samples were collected from 115 Lithuanian patients with non-cardia gastric cancer and 110 age- and sex-matched controls without cancer. Heat-stable, low-molecular-mass, and outer memb

The Applicability of Enzymes in Cellulose Ether Analysis

Six methyl cellulose (MC) samples, one with a IDS Of 1.32 and five with a DS between 1.83 and 1.88, were degraded with five different enzymes or enzyme preparations containing endoglucanases. The main goal was to investigate whether enzymes could be used for determination of heterogeneity of the substituent distribution along the cellulose chain. To obtain information about the heterogeneity it wa

Influence of non-Markovian relaxation processes on self-induced transparency: Memory function theory for optical solitons

The influence of transverse relaxation on the resonance soliton (2 pi hyperbolic-secant pulse) in solids is considered. It is shown that memory effects can be considered in terms of generalized non-Markovian optical Bloch equations. The equations of self-induced transparency with a memory function are presented. Explicit forms for the first-order effects of this relaxation on the frequency shift a

Isolation and characterization of polymorphic microsatellite loci in the field vole, Microtus agrestis, and their cross-utility in the common vole, Microtus arvalis

We developed nine polymorphic microsatellite loci for the field vole, Microtus agrestis. The number of alleles ranged from five to 15 and observed heterozygosities ranged from 0.40 to 1.00. We also tested the microsatellite loci for amplification and polymorphism in the congeneric species Microtus arvalis. Five of the nine loci were successfully analysed in this species. The microsatellite markers

On A2-codes including arbiter's attacks

We comment on the work by R. Taylor presented at Euro-Crypt'94 (see this proceedings). We first extend some known results on authentication codes with arbitration to the case when protection against arbiter's attacks is provided. We give lower bounds on the secret key size for each participant and give a construction showing that these bounds are tight. These results improve upon previously known

Determination of drug-protein binding using supported liquid membrane extraction under equilibrium conditions

A technique for determination of drug-protein binding based on a membrane extraction technique termed "equilibrium sampling through membrane (ESTM)" is presented. It involves the establishment of an equilibrium between an aqueous buffer and either a blood plasma sample or a matched buffer, both containing the drug. Analysis of the aqueous buffer in the two cases gives the drug-protein binding. The

A water activity control system for enzymatic reactions in organic media

A water activity control system for enzymatic synthesis in organic media, for litre-scale reactors has been constructed. Water activity, a(w), is a key factor when using enzymes in non-conventional media and the optimum value varies for different enzymes. The control system consists of a water activity sensor in the headspace of a jacketed glass reactor (equipped with narrow steel tubes to introdu

Self-reported health complaints and their prediction of overall and health-related quality of life among elderly people

Objective: To describe and compare self-reported health complaints, overall and health-related quality of life and to investigate how health complaints, age, gender, marital status, living and dwelling conditions and socio-economy predicted overall and health-related quality of life. Data and Method: A sample of 469 persons (aged 75-99) responded to a postal questionnaire. Multiple linear regressi

Chronic lithium treatment decreases NG2 cell proliferation in rat dentate hilus, amygdala and corpus callosum

An increasing number of investigations suggest volumetric changes and glial pathology in several brain regions of patients with bipolar disorder. Lithium, used in the treatment of this disorder, has been reported to be neuroprotective and increase brain volume. Here we investigate the effect of lithium on the proliferation and survival of glial cells positive for the chondroitin sulphate proteogly

Cryo-TEM observation of 3-dimensionally ordered aggregates of 5-nm gold particles in organic solvents

In this article, we show evidence for the assembly of ordered 3-dimensional aggregates of 5-nm gold particles in toluene, 1-octanol, n-decane, and chloroform. The use of plunge-freezing allows to freeze the solution containing the aggregates at a rate which does not allow reorganisation of the particles during sample preparation. The samples were then observed using cryo-transmission electron micr

Generation of a conditionally null allele of the laminin alpha 1 gene

Laminins are heterotrimeric glycoproteins of the basement membranes. Laminin 1 (alpha 1, beta 1, gamma 1) is the major laminin expressed during early mouse embryogenesis. To gain access, to the physiological function of laminin alpha 1 chain, we developed a conditionally null allele of its encoding gene (Lama1) using the cre/loxP system. Floxed-allele-carrying mice (Lama1(flox/flox)) display no ov