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Bandsawing. Part III: stress analysis of saw tooth microgeometry

This article presents a stress analysis of a saw tooth. The analysis aims to determine the stress distribution for various egde load and varying microgeometry. The analysis is performed on a three-dimensional finite element model representing the tip of a saw tooth. The 3D model makes it possible to model the load distribution and study stress distributions across the width of the teeth with a suf

Fibreoptic laryngotracheoscopy via the laryngeal mask airway in children

BACKGROUND: Fibreoptic laryngotracheoscopy via the laryngeal mask airway-previously reported in adults but not in children-gives a better endoscopic view of the upper airway than does endoscopy via an endotracheal tube. METHOD: The endoscopic procedure was carried out via a size 2 laryngeal mask in 4 spontaneously breathing children between 1 and 6 years old. Anaesthesia was induced and maintained

A simple correlation-corrected theory of systems described by screened Coulomb interactions

We present a simple correlation-corrected density functional treatment of dispersions containing macroions, where these are assumed to interact via screened Coulomb potentials, as given by Debye-Hückel theory. A straightforward mean-field description even fails to qualitatively capture important correlation effects displayed by such systems. However, if an effective, correlation-corrected potentia

Rangeland development of the Mu Us sandy land in semiarid China: An analysis using landsat and NOAA remote sensing data

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

Diffusion in an inhomogeneous system: NMR studies of diffusion in highly concentrated emulsions

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

Relaxed circadian rhythm in zooplankton along a latitudinal gradient

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

Science drivers of a 50-m AO telescope

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

H2S ultrafast dissociation probed by energy-selected resonant Auger electron-ion coincidence measurements

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 molecular basis of Sanfilippo syndrome type B

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

Racemic, S(+)- and R(-)-ketamine do not increase elevated intracranial pressure

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

Breast cancer and abortion: collaborative reanalysis of data from 53 epidemiological studies, including 83?000 women with breast cancer from 16 countries

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

Isospin effects on two-particle correlation functions in intermediate energy heavy ion reactions

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

In vivo and in vitro studies of Bacillus subtilis ferrochelatase mutants suggest substrate channeling in the heme biosynthesis pathway.

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

Dental behavioural management problems and dental caries prevalence in 3-to 6-year-old Swedish children born preterm

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

Increased thirst and drinking in Huntington's disease and the R6/2 mouse

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

Graph Laplacians and Topology

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.

Seasonal variability of thermal regime in a shallow ice covered lake

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

Measuring Event Risk

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