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Degradation of the dry semiarid ecosystems in the Mu Us Sandy Land of north central China was explored using high-resolution satellite images from 1978, 1987 and 1996. This study monitored both changes in grassland biomass production and reclamation activities to detect the nature and scale of land degradation since major economic reforms were introduced in 1978. The position of the high-resolutio

In this study the self-diffusion of different species in highly concentrated water-in-oil emulsions was investigated by means of the NMR diffusometry approach. The emulsions contained 96% aqueous solutions of salt or other additives; hept ne was used as the oil phase. The surfactants, used to stabilize the emulsion, were soybean phosphatidylcholine and C12EO4. The water drops were about 1.5 mum in

To test whether aquatic invertebrates are able to adjust their diel migratory cycle to different day length and presence of predators, we performed standardized enclosure experiments in shallow lakes at four different latitudes from southern Spain, with strong night-day cycles, to Finland where daylight is almost continuous during summer. We show here that nearly continuous daylight at high latitu

Some leading science programs undertaken with Very Large Telescopes and challenges driving the progress of the Extremely Large Telescopes are discussed together with the corresponding requirements. They concern expolanets, Earth-like planets, habitable zones, formation of stars and galaxies, first stars and cosmology. A description is attempted

We have studied the ultrafast dissociation of the H2S molecule upon S 2p(3/2)-> 6a(1) inner-shell excitation by combining high-resolution resonant Auger spectroscopy and energy-selected Auger electron-ion coincidence measurements. Auger final states have been correlated to the different fragmentation pathways (S+, HS+, and H2S+ ions). As an original result, we evidence a three-step mechanism to de

The Sanfilippo syndrome type B is a lysosomal storage disorder caused by deficiency of alpha-N-acetylglucosaminidase; it is characterized by profound mental deterioration in childhood and death in the second decade. For understanding the molecular genetics of the disease and for future development of DNA-based therapy, we have cloned the cDNA and gene encoding alpha-N-acetylglucosaminidase. Clonin

Background: There is controversy regarding the influence of ketamine and its enantiomers on cerebral haemodynamics at increased intracranial pressure (ICP). This study was designed to compare cerebrovascular responses, with particular respect to ICP, to bolus injections of racemic, S(+)- and R(-)-ketamine in an experimental model of intracranial hypertension. Methods: Nine pigs were anaesthetised

BACKGROUND: The Collaborative Group on Hormonal Factors in Breast Cancer has brought together the worldwide epidemiological evidence on the possible relation between breast cancer and previous spontaneous and induced abortions. METHODS: Data on individual women from 53 studies undertaken in 16 countries with liberal abortion laws were checked and analysed centrally. Relative risks of breast cancer

Exclusive data from an intensity interferometry experiment are presented, where, for the first time, the technique of two-nucleon correlation functions is applied to isotopically selected data, with the aim to study the isospin dependence of the nuclear equation of state (EOS). The different correlation function strength, observed for two isotopically separated systems, E/A = 61 MeV Ar-36 + Sn-112

Ferrochelatase (EC 4.99.1.1) catalyzes the last reaction in the heme biosynthetic pathway. The enzyme was studied in the bacterium Bacillus subtilis, for which the ferrochelatase three-dimensional structure is known. Two conserved amino acid residues, S54 and Q63, were changed to alanine by site-directed mutagenesis in order to detect any function they might have. The effects of these changes were

Background. Today, most children born preterm survive without major impairments. But high frequencies of cognitive and behavioural difficulties arise. Studies on dental behavioural management problems (DBMP) in these children are lacking. In addition, studies on caries prevalence are few and inconclusive. Aim. This study aims to compare the frequency of behavioural problems and poor compliance wit

While Huntington's disease (HD) is a condition that primarily involves the basal ganglia, there is evidence to suggest that the hypothalamus is also affected. Because the osmoreceptors regulating thirst are situated in the circumventricular region of the hypothalamus, we were interested in whether altered thirst is a part of the HD phenotype. We used the LABORAS behavioural monitoring system and w

Laplace operators on metric graphs are considered. It is proven that for compact graphs the spectrum of the Laplace operator determines the total length, the number of connected components, and the Euler characteristic. For a class of non-compact graphs the same characteristics are determined by the scattering data consisting of the scattering matrix and the discrete eigenvalues.

A systematic study was conducted over six years (1994-1999) on a shallow ice covered lake in the Russian Republic of Karelia with the aim of developing better understanding of some physical processes occurring in shallow ice-covered lakes. The average ice-covered period was 182 days while the longest ice-covered period was 193 days. The average lake water temperature at ice formation was 0.5-10deg

This paper decomposes the popular risk measure Value-at-Risk (VaR) into one jump- and one continuous component. The continuous component corresponds to general market risk and the jump component is proportional to the event risk as defined in the Basel II accord. We find that event risk, which is currently not incorporated into most banks’ VaR models, comprises a substantial part of total VaR. It

Background: Early detection of prostate cancer (PCa) centers on measurements of prostate-specific antigen (PSA), but current testing practices suffer from lack of specificity and generate many unnecessary prostate biopsies. Soluble urokinase plasminogen activator receptor (uPAR) is present in blood in both intact and cleaved forms. Increased uPAR in blood is correlated with poor prognosis in vario

The role of spontaneous and induced abortion on breast cancer risk is examined among 267,361 women recruited into the European Prospective Investigation into Cancer and nutrition between 1992 and 2000. The data were collected from 20 centers, across 9 countries, and included information on a total of 4,805 women with breast cancer, of whom 1,657 reported having ever had any type of abortion. Overa

Introduction Alveolar dead space reflects phenomena that render arterial partial pressure of carbon dioxide higher than that of mixed alveolar gas, disturbing carbon dioxide exchange. Right-to-left shunt fraction (Qs/Qt) leads to an alveolar dead space fraction (VdA(S)/VtA; where VtA is alveolar tidal volume). In acute respiratory distress syndrome, ancillary physiological disturbances may include

The glutathione S-transferase P1 genotype (GSTP1) is involved in the inactivation of cigarette smoke carcinogens, and sequence variation in the gene may alter bladder cancer susceptibility. To examine the association between GSTP1lle 105Val and bladder cancer, the authors undertook a meta- and pooled analysis. Summary crude and adjusted odds ratios and corresponding 95% confidence intervals were p