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Fractional 13C enrichment of isolated carbons using [1-13C]- or [2-13C]-glucose facilitates the accurate measurement of dynamics at backbone Ca and side-chain methyl positions in protein

A simple labeling approach is presented based on protein expression in [1-C-13]- or [2-C-13]-glucose containing media that produces molecules enriched at methyl carbon positions or backbone C-alpha sites, respectively. All of the methyl groups, with the exception of Thr and Ile(delta 1) are produced with isolated C-13 spins (i.e., no C-13-C-13 one bond couplings), facilitating studies of dynamics

Comparison of mathematical formulas used for estimation of DNA synthesis time of bromodeoxyuridine-labelled cell populations with different proliferative characteristics

Growth kinetic data of human tumours, obtained by flow cytometric analysis of cells labelled with bromodeoxyuridine (BrdUrd) might provide prognostic information and allow prediction of response to radio- and chemotherapy. However, the theoretical models applied for calculation of growth kinetic data are not fully evaluated. The purpose of this study was to investigate the dependence of the estima

Catalytic Anisotropy of MoO3 in the Oxidative Ammonolysis of Toluene

The oxidative ammonolysis of toluene, i.e., ammoxidation without the presence of molecular oxygen, was studied over a series of samples of MoO3 crystals. The specific surface areas of the various faces were determined from SEM micrographs. Correlations between activities and surface planes were found. For the formation of nitrile the specific activity decreased in the order {001} and {h01} > {100}

Dynamics of intersexual conflict over precopulatory mate guarding in two populations of the isopod Idotea baltica

Aggressiveness during intersexual conflicts is predicted to depend on its costs, the value of winning and the power asymmetry of the contestants, all of which may vary between populations. In the marine isopod Idotea baltica (Pallas) a conflict occurs as females resist the attempts by males to start precopulatory mate guarding. We analysed contest dynamics with respect to female maturity stage, th

Resistance to NMDA toxicity correlates with appearance of nuclear inclusions, behavioural deficits and changes in calcium homeostasis in mice transgenic for exon 1 of the huntington gene

Transgenic Huntington's disease (HD) mice, expressing exon 1 of the human HD gene (lines R6/1 and R6/2), are totally resistant to striatal lesions caused by the NMDA receptor agonist quinolinic acid (QA). Here we show that this resistance develops gradually over time in both R6/1 and R6/2 mice, and that it occurred earlier in R6/2 (CAG-155) than in R6/1 (CAG-115) mice. The development of the resis

Is it possible to improve the patch-test diagnostics for isocyanates? A stability study of petrolatum preparations of diphenylmethane-4,4'-diisocyanate and polymeric diphenylmethane diisocyanate.

We have previously shown that the concentration of diphenylmethane-4,4'-diisocyanate (4,4'-MDI) in commercial test preparations was so low that patch testing with the same was not reliable. The stability of 4,4'-MDI in petrolatum (pet.) was compared with pet. preparations of polymeric diphenylmethane diisocyanate (PMDI), which consists of a complex mixture of monomeric isomers and oligomers of MDI

Cancer incidence in relatives of a population-based set of cases of early-onset breast cancer with a known BRCA1 and BRCA2 mutation status

Background Relatives of breast cancer cases have an increased risk of the disease. The risk increases with increasing numbers and decreasing age of onset of affected relatives. In families with a BRCA1 or a BRCA2 mutation, individual carrier status predicts the risk of breast cancer. In relatives of cases where both BRCA1 and BRCA2 mutations are excluded, the risk remains undetermined. Methods Sta

Quantum ratchets and quantum heat pumps

Quantum ratchets are Brownian motors in which the quantum dynamics of particles induces qualitatively new behavior. We review a series of experiments in which asymmetric semiconductor devices of sub-micron dimensions are used to study quantum ratchets for electrons. In rocked quantum-dot ratchets electron-wave interference is used to create a non-linear voltage response, leading to a ratchet effec

Tre lokaler för barkbjörnbär i Höörs kommun

The former winter sports camp Frostavallen was connected by a track to the nearest railway halt, now part of the Skaneleden subtrail Ridge to Ridge. Rubus echinatus, R. senticosus and R. sciocharis occur at three sites in the area, probably a result of timber import half a century ago.

The state of the sand-steppe vegetation of eastern Scania (Skåne) in early spring 2003

The sand-steppe is a unique vegetation type almost exclusively found in eastern Scania. It is dominated by rare species such as Koeleria glauca, Festuca polesica, Phleum arenarium, Dianthus arenarius, Astragalus arenarius, Anthericum ramosum and Syntrichia ruraliformis. In 1994, the area covered by this vegetation was estimated to be 57 ha but in the present study only 20-30 ha were refound. Prere

Estimating the spatial scale of pollen dispersal in the cultural landscape of southern Sweden

The primary aim of the study was to estimate the spatial scale of pollen dispersal and deposition for pollen assemblages from moss polsters in the cultivated landscape of southern Sweden, as a mean to improve future studies of the pollen/vegetation relationship in the region, and interpretation of fossil pollen data in terms of past cultural landscapes. This can be done by estimating the 'relevant

Monitoring the European standard series in 10 centres 1996-2000

A 5-year retrospective study of the frequency of sensitization to the 25 allergens of the European standard series (ESS) was conducted in 10 centres in 8 European countries. Included were the results of 26 210 patients. The range in sensitivities differed moderately between the centres. Combining results of different centres and drawing conclusions on incidences can be done only with great care. T

J/psi production from proton-proton collisions at root s=200 GeV

J/psi production has been measured in proton-proton collisions at roots=200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at the Relativistic Heavy Ion Collider. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calcul

Adsorption and Structural Environment of Co(Ii) at the Zinc Oxide-Aqueous and Zinc Sulfide-Aqueous Solution Interfaces

Adsorption of Co(II) at the aqueous interfaces of ZnO and ZnS (wurtzite) has been studied by classical wet-chemical methods, and the structure and composition of Co adsorption complexes at these interfaces have been determined by in-situ X-ray absorption fine structure (XAFS) spectroscopy. On both adsorbents, adsorption as a function of pH shows the normal behavior, i.e., a pronounced adsorption w

Three-pulse photon echo of an excitonic dimer modeled via Redfield theory

In this article the third-order response of an excitonically coupled dimer is studied. The three-pulse photon echo signals were calculated by extracting polarization components from the total polarization in the corresponding phase-matched directions. The total nonlinear response was obtained by numeric propagation of the density matrix, with the exciton-vibrational coupling modeled via Redfield r

Can panel data really improve the predictability of the monetary exchange rate model?

A common explanation for the inability of the monetary model to beat the random walk in forecasting future exchange rates is that conventional time series tests may have low power, and that panel data should generate more powerful tests. This paper provides an extensive evaluation of this power argument to the use of panel data in the forecasting context. In particular, by using simulations it is

Enhanced enzymatic conversion of softwood lignocellulose by poly(ethylene glycol) addition

Ethanol production from lignocellulose has great potential and is an important step in changing fuel consumption to a more environmentally friendly alternative. Lignocellulose is a large source of biomass. However, with lignocellulose and softwood lingocellulose in particular, high conversion of cellulose into fermentable sugars requires large amounts of enzymes. Addition of surfactants is known t

Amphiphilic polymer gel electrolytes. 3. Influence of the ionophobic-ionophilic balance on the ion conductive properties

Gel electrolytes based on amphiphilic copolymethacrylates containing ethylene oxide (EO)(n) side chains as ionophilic units and fluorocarbon (CF,), side chains as ionophobic units showed a substantial increase in ion conductivity, as compared to corresponding gels based on homopolymers of (EO),, methacrylate. The highest ion conductivity was found for a gel based on a copolymer composed of 24 wt%