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Gelled polymerizable microemulsions. 2. Microstructure

Using bicontinuous microemulsions as templates opens a new field for the design of novel structures and thus novel materials, but has significant challenges due to the very small composition and temperature windows in which microemulsions are bicontinuous. In previous work we had shown that we can take a ternary base system (water-n-dodecane-C13/15E5), add monomer and cross-linker (N-isopropylacry

Double-strand break DNA repair genotype predictive of later mortality and cancer incidence in a cohort of non-smokers

We followed-up for mortality and cancer incidence 1088 healthy non-smokers from a population-based study, who were characterized for 22 variants in 16 genes involved in DNA repair pathways. Follow-up was 100% complete. The association between polymorphism and mortality or cancer incidence was analyzed using Cox Proportional Hazard regression models. Ninety-five subjects had died in a median follow

Migration as a risk factor for schizophrenia: a Danish population-based cohort study.

Background A growing body of evidence suggests that migration is a risk factor for the development of schizophrenia, although the putative mechanism remains obscure. Aims To examine immigrant background and history of foreign residence as risk factors for schizophrenia. Method Using data from the Danish Civil Registration System, we established a population-based cohort of 2.14 million persons r

Direct measurement of intraparticle fluid velocity in superporous agarose beads

Superporous agarose beads contain both normal diffusion pores and special, very wide superpores through which part of the chromatographic flow is transported, a situation that may greatly improve the chromatographic performance. For the first time such pore flow was measured directly by following the movement of microparticles (dyed yeast cells) through superporous beads packed in a chromatographi

Migration speed and scheduling of annual events by migrating birds in relation to climate change

Empirical evidence for changed timing of migration in birds is emerging from both American and Euro-African migration systems. These changes are usually interpreted as a consequence of changes in climate. Responses in timing of migration and breeding may differ among species, and the adaptive significance is not well understood. There is a lack of theoretical understanding about time-shifts in lif

The future of PID control

This paper presents the state of the art of PID control and reflectson its future. Particular issues discussed include specifications,stability, design, applications, and performance of PID control. Thepaper ends with a discussion of alternatives to PID and its future.

Cerebral Inflammatory Response after Fetal Asphyxia and Hyperoxic Resuscitation in Newborn Sheep.

Resuscitation with pure oxygen at birth after fetal asphyxia may aggravate brain damage by inducing pro-inflammation. The toll-like receptors (TLRs) may serve a pro-inflammatory role in hyperoxemia during ischemia-reperfusion. Sixteen near-term fetal sheep (132-136 d) were subjected to 10 min of cord occlusion, delivery and mechanical ventilation with 100% O-2 (n = 8), or 21% O-2 (n = 8) for 30 mi

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