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Research on magnetic confinement of high-temperature plasmas has the ultimate goal of harnessing nuclear fusion for the production of electricity. Although the tokamak1is the leading toroidal magnetic-confinement concept, it is not without shortcomings and the fusion community has therefore also pursued alternative concepts such as the stellarator. Unlike axisymmetric tokamaks, stellarators possess a three-dimensional (3D) magnetic field geometry. The availability of this additional dimension opens up an extensive configuration space for computational optimization of both the field geometry itself and the current-carrying coils that produce it. Such an optimization was undertaken in designing Wendelstein 7-X (W7-X)2, a large helical-axis advanced stellarator (HELIAS), which began operation in 2015 at Greifswald, Germany. A major drawback of 3D magnetic field geometry, however, is that it introduces a strong temperature dependence into the stellarator’s non-turbulent ‘neoclassical’ energy transport. Indeed, such energy losses will become prohibitive in high-temperature reactor plasmas unless a strong reduction of the geometrical factor associated with this transport can be achieved; such a reduction was therefore a principal goal of the design of W7-X. In spite of the modest heating power currently available, W7-X has already been able to achieve high-temperature plasma conditions during its 2017 and 2018 experimental campaigns, producing record values of the fusion triple product for such stellarator plasmas3,4. The triple product of plasma density, ion temperature and energy confinement time is used in fusion research as a figure of merit, as it must attain a certain threshold value before net-energy-producing operation of a reactor becomes possible1,5. Here we demonstrate that such record values provide evidence for reduced neoclassical energy transport in W7-X, as the plasma profiles that produced these results could not have been obtained in stellarators lacking a comparably high level of neoclassical optimization.

Statin-based treatments reduce cardiovascular disease (CVD) risk in patients with non-dialysis chronic kidney disease (CKD), but it is unclear which regimen is the most cost-effective. We used the Study of Heart and Renal Protection (SHARP) CKD-CVD policy model to evaluate the effect of statins and ezetimibe on quality-adjusted life years (QALYs) and health care costs in the United States (US) and the United Kingdom (UK). Net costs below $100,000/QALY (US) or £20,000/QALY (UK) were considered cost-effective. We investigated statin regimens with or without ezetimibe 10 mg. Treatment effects on cardiovascular risk were estimated per 1-mmol/L reduction in low-density lipoprotein (LDL) cholesterol as reported in the Cholesterol Treatment Trialists’ Collaboration meta-analysis, and reductions in LDL cholesterol were estimated for each statin/ezetimibe regimen. In the US, atorvastatin 40 mg ($0.103/day as of January 2019) increased life expectancy by 0.23 to 0.31 QALYs in non-dialysis patients with stages 3B to 5 CKD, at a net cost of $20,300 to $78,200/QALY. Adding ezetimibe 10 mg ($0.203/day) increased life expectancy by an additional 0.05 to 0.07 QALYs, at a net cost of $43,600 to $91,500/QALY. The cost-effectiveness findings and policy implications in the UK were similar. In summary, in patients with non-dialysis-dependent CKD, the evidence suggests that statin/ezetimibe combination therapy is a cost-effective treatment to reduce the risk of CVD.

The ionospheric response to explosions which occur at or below the Earth's surface has been noted since the first detonations of nuclear devices during the early period of aboveground testing. Acoustic gravity waves and traveling ionospheric disturbances were detected in association with test explosions carried out by the Union of Soviet Socialist Republics in Novaya Zemlya in 1961. While research in this area has continued, the standards accepted by the Comprehensive Nuclear Test Ban Treaty for detection and confirmation of nuclear explosions have been based on (1) seismic, (2) hydroacoustic, (3) infrasound, and (4) radionuclide monitoring from ground detectors. We suggest that ionospheric sensing offers a complementary methodology that may allow for robust confirmation of explosive events. One method of ionospheric monitoring of explosive events is analysis of total electron content (TEC), available by processing data from Global Navigation Satellite System (GNSS) receivers distributed globally on land masses. Traveling ionospheric disturbances observed by their signature in TEC have been used to detect and confirm mine collapses, mine blasts, earthquakes, volcanic eruptions, and meteorite strikes as well as underground nuclear tests. While an integrated measurement like TEC is not as sensitive to small‐amplitude density perturbations as other methods, the existence of large networks of continuously operating GNSS stations makes this an intriguing new monitoring asset. We report on the current capabilities for detection of explosions via the ionosphere, the outstanding challenges, and prospects for future developments that have potential to augment the current standards for detection and confirmation of nuclear detonations. By leveraging the worldwide network of GNSS receivers, robust confirmation of impulsive events is possible. This methodology complements existing technologies approved by the Comprehensive Test Ban Treaty. The article outlines background theory, new approaches to monitoring of explosions, and challenges that remain to be addressed. Detection of aboveground and belowground explosive events is possible by ionospheric monitoringMethodology leverages global GNSS availability, but attribution and validation are outstanding challengesIonospheric observations coupled with numerical simulations can add robust confirmation to traditional methods of detection

Modern techniques for specifying the ionosphere include the use of ionosondes, which both transmit and receive sweep soundings in the high‐frequency (HF) band. We replicate this process by observing the broad band emission from lightning using the Long Wavelength Array, Sevilleta, radio telescope. We use this station to observe the powerful broadband radio bursts from the breakdown of air that occurs during lightning flashes. For nearby lightning we observe both the direct line of sight and the delayed ionospheric reflection. By correlating the amplitude time series from the direct line of sight to that of the ionospheric reflection, we can accurately measure the group delay as a function of frequency. By separating into right‐hand circular and left‐hand circular, we can derive both the O mode and X mode ionograms. This novel technique allows for accurate ionograms to be made even in restricted frequency bands and provides a means to probe density profiles at multiple locations of the ionosphere on short time scales with a single receiver station. In this paper, we present a novel technique that leverages the natural radio emissions from lightning as a signal source to measure the electron density profile of the bottomside ionosphere. Such profile measurements are known as ionograms. Previous methods to produce ionograms make use of RADAR systems composed of both a transmitter and receiver. Our method, however, requires only a receiver placed in proximity to ongoing lightning storms. These measurements are the first of their kind to use naturally occurring radio emission to produce ionograms. This work opens the door to further research, where scattered storms could provide key measurements for specifying the spatial and temporal structure present within the ionosphere. Lightning generates the required signal needed for ionospheric specificationThe ionograms presented here are the first to be derived from lightning measurementsMeasurements are not subject to frequency restrictions

Fjords form the gateway between the open ocean and the Greenland Ice Sheet (GIS) and consequently play a crucial role for the stability of the Ice Sheet. Hydrographic observations, especially with seasonal resolution, from these fjords are limited making it difficult to assess linkages between the fjord, coastal water masses, and freshwater discharge from GIS. Here we present a decade‐long monthly hydrographic time series from a southwest Greenland fjord in direct contact with GIS. Our observations reveal significant temporal and spatial water mass variations related to coastal, glacial, and atmospheric dynamics. During winter, the fjord circulation is dominated by seasonal dense coastal inflows and the timing of these inflows determines intermediate and deepwater temperatures. During summer, runoff from GIS leads to a pronounced freshening of the fjord. In general, the fjord's seasonal circulation system damps the seasonal variation in temperature in the fjord. This leads to a seasonal temperature range in the intermediate layer in the inner part of the fjord that is half the observed range at the fjord entrance. Changes in mean water temperatures in the intermediate layer seem predominantly linked to local coastal water masses, where cold winter/warm summer events decrease/increase the mean water temperatures. Consequently, these events play an important role in heat transport toward glacier termini. Fjords form the gateway between warm open ocean water and the Greenland Ice Sheet and play a crucial role for the stability of the Ice Sheet. Temperature and salinity observations from these fjords are limited, making it difficult to understand the link between the fjord, coastal water masses, and freshwater discharge from the Ice Sheet. We present a decade‐long monthly temperature and salinity time series from a southwest Greenland fjord in direct contact the Ice Sheet. Our data reveal that changes in mean water temperatures in the water mass responsible for melting the Ice Sheet is linked to local coastal water masses, where cold winter events decrease and warm summer events increase the mean water temperatures close to marine terminating glaciers. We present a decade‐long seasonal hydrographic time series from a major Greenland tidewater outlet glacial fjordThe fjord's seasonal circulation system damps the coastal temperature signal in the fjordMean temperature shifts in the inner fjord are predominantly linked to local coastal water masses and can be related to local atmospheric forcing

The two leading concepts for confining high-temperature fusion plasmas are the tokamak and the stellarator. Tokamaks are rotationally symmetric and use a large plasma current to achieve confinement, whereas stellarators are non-axisymmetric and employ three-dimensionally shaped magnetic field coils to twist the field and confine the plasma. As a result, the magnetic field of a stellarator needs to be carefully designed to minimize the collisional transport arising from poorly confined particle orbits, which would otherwise cause excessive power losses at high plasma temperatures. In addition, this type of transport leads to the appearance of a net toroidal plasma current, the so-called bootstrap current. Here, we analyse results from the first experimental campaign of the Wendelstein 7-X stellarator, showing that its magnetic-field design allows good control of bootstrap currents and collisional transport. The energy confinement time is among the best ever achieved in stellarators, both in absolute figures (τE> 100 ms) and relative to the stellarator confinement scaling. The bootstrap current responds as predicted to changes in the magnetic mirror ratio. These initial experiments confirm several theoretically predicted properties of Wendelstein 7-X plasmas, and already indicate consistency with optimization measures. Results from the first experimental campaign of the Wendelstein 7-X stellarator demonstrate that its magnetic-field design grants good control of parasitic plasma currents, leading to long energy confinement times.

The Northeast Greenland shelf is a broad Arctic shelf located between Greenland and Fram Strait. It is the principal gateway for sea ice export and sea ice‐associated freshwater from the Arctic Ocean. Sea ice thickness has decreased by 15% per decade since the early 1990s and meteoric freshwater discharge has increased. The consequence of changing sea‐ice and freshwater conditions in the region on ocean dynamics and the biological system remains unknown. Determining the source(s) of freshwater is important to be able to understand how the area will react to future upstream change. Here we present a synoptic survey of the Northeast Greenland shelf and slope with observations of hydrography, the nutrients nitrate, phosphate and silicate, and conservative tracers δ18O, δ2H, and total alkalinity during late summer 2017. We compare these to previously published values, including those which identify Pacific and Atlantic water, the Siberian shelf seas, and the six largest Arctic rivers. We show that a major source of freshwater on the Northeast Greenland shelf during late summer 2017 is the Laptev Sea and find no conclusive evidence of Pacific Water. Our observations indicate a direct link between Northeast Greenland hydrology and processes occurring on Eurasian shelves. The Northeast Greenland shelf is a shallow marine environment between Greenland and the adjacent Fram Strait, where a large fraction of the Arctic Ocean freshwater is exported into the North Atlantic. To predict the regional response to climate change, it is important to determine what the remote sources of freshwater on the shelf are and how these influence mixing. We compare the chemistry of the water found at different locations on the shelf with those found in other areas of the Arctic Ocean to determine where it comes from and conclude that most of the water on the Northeast Greenland shelf in late summer of 2017 is from the Laptev Sea, while surface waters have subsequently been modified by sea ice melt. Northeast Greenland Winter Water is fresher than in the 1990sThe cold halocline layer is a brine‐enhanced mixture of river discharge and Atlantic WaterThe river discharge is primarily sourced from the Laptev Sea Northeast Greenland Winter Water is fresher than in the 1990s The cold halocline layer is a brine‐enhanced mixture of river discharge and Atlantic Water The river discharge is primarily sourced from the Laptev Sea

The objectives were to determine effects of diet NE and an exogenous carbohydrase on growth performance and physiological parameters of weanling pigs fed a corn-soybean meal (SBM) diet or diets containing high protein canola meal (CM-HP) or conventional canola meal (CM-CV). A total of 492 pigs (initial BW: 9.15 ± 0.06 kg) were used in a randomized complete block design with 12 dietary treatments and 9 pens per treatment. A control diet based on corn and SBM and 4 diets containing 20% or 30% CM-HP or 20% or 30% CM-CV were formulated to a similar NE by adjusting inclusion of choice white grease. Four additional diets also contained 20% or 30% CM-HP or 20% or 30% CM-CV, but no additional choice white grease, and NE in these diets, therefore, was less than in the control diet. The control diet and the diets containing 30% CM-HP or CM-CV without increased choice white grease were also formulated with inclusion of an exogenous carbohydrase. Pigs were fed experimental diets for 22 d and 1 pig per pen was sacrificed at the conclusion of the experiment. Results indicated that compared with the control diet, there was no impact of canola meal on final BW, ADG, ADFI, or G:F, but pigs fed CM-CV had greater (P< 0.05) final BW, ADG, and ADFI than pigs fed CM-HP, and pigs fed diets with reduced NE had greater (P< 0.05) ADG and ADFI than pigs fed diets with constant NE. Only minor effects of CM-HP or CM-CV on intestinal weight, gut fill, digesta pH, cecal VFA concentrations, and serum concentrations of urea N, total N, or albumin were observed, but the weight of the thyroid gland increased (P< 0.05) as the concentration of dietary canola meal increased. Serum concentrations of IgG were reduced if canola meal was included in the diets without the carbohydrase, but that was not the case if the carbohydrase was included in the diet (interaction, (P< 0.05). In conclusion, up to 30% CM-HP or CM-CV in diets fed to weanling pigs from 2 wk postweaning did not impact growth performance compared with pigs fed a corn-SBM diet, and NE in diets containing canola meal does not have to be similar to that of corn-SBM diets. However, inclusion of CM-CV containing 4.43 µmol/g glucosinolates in the diets resulted in improved growth performance compared with inclusion of CM-HP containing 12.60 µmol/g glucosinolates.

Supplementation of xylanase to pig diets can hydrolyze arabinoxylan (AX) into lower molecular weight compounds and thereby decrease the viscosity and improve nutrient utilization. Xylanase supplementation has, however, shown variable effects in diets containing wheat, rye, and combinations thereof. Differences in animal age, enzyme source and dose, target substrate, and diet processing may explain this. The objective was to study the effect of increasing doses of endo-1,4-β-xylanase from Trichoderma reeseion apparent total tract digestibility (ATTD) of OM, starch, nonstarch polysaccharides (NSP), AX, fat, N, and P of rye fed to growing pigs. Twenty-four 47-kg pigs were assigned to 4 diets containing 97.85% rye and 0, 4,000, 8,000, or 16,000 units xylanase/kg (as-fed basis). Pigs were placed in metabolic cages for 10 d: 5 d for adaption and 5 d for total but separate collection of feces and urine. The ATTD of OM, starch, N, and P did not differ among treatments. The ATTD of total NSP, AX, and fat was, however, higher (P< 0.05) in pigs fed 8,000 units xylanase/kg compared with pigs fed 4,000 and 16,000 units xylanase/kg but not different from pigs fed the control diet without xylanase. The urinary excretion of N and P did not differ among treatments. Besides a linear effect (P= 0.05) on ATTD of fat, there were neither linear nor quadratic responses to xylanase supplementation on ATTD of OM, starch, NSP, AX, fat, N, and P. In conclusion, supplementation of endo-1,4-β-xylanase did not improve the nutritional value of rye in growing pigs.

Using the narrowband all-sky imager mode of the Long Wavelength Array (LWA1), we have now detected 30 transients at 25.6 MHz, 1 at 34 MHz, and 93 at 38.0 MHz. While we have only optically confirmed that 37 of these events are radio afterglows from meteors, evidence suggests that most, if not all, are. Using the beam-forming mode of the LWA1, we have also captured the broadband spectra between 22.0 and 55.0 MHz of four events. We compare the smooth, spectral components of these four events and fit the frequency-dependent flux density to a power law, and find that the spectral index is time variable, with the spectrum steepening over time for each meteor afterglow. Using these spectral indices along with the narrowband flux density measurements of the 123 events at 25.6 and 38 MHz, we predict the expected flux densities and rates for meteor afterglows potentially observable by other low-frequency radio telescopes. We have computed rates of meteor radio afterglowsWe have measured the spectra of four meteor radio afterglows and have fit them to a power lawWe use the power law fit and the measured rates to predict event rates for other telescopes at other frequencies

Simvastatin, 20mg, plus ezetimibe, 10mg, daily (simvastatin plus ezetimibe) reduced major atherosclerotic events in patients with moderate to severe chronic kidney disease (CKD) in the Study of Heart and Renal Protection (SHARP), but its cost-effectiveness is unknown.

En ce qui concerne le développement des centrales nucléaires nouvelles, ABB a dès le début adopté une philosophie d'indépendance et d'évolution prudente. En conséquence, les concepts de base des offres d'ABB en matière de centrales nucléaires pour le futur seront deux types de réacteurs évolutifs, basés sur des versions antérieures qui ont connu beaucoup de succès. Tous les deux peuvent être étudiés en détail, homologués et construits en conformité avec toutes les règles de sûreté nucléaire, appliquées ou projetées dans les pays d'occident. Le BWR 90 est un de ces types - une conception nouvelle basée sur une technologie éprouvée.

The waters on the West Greenland continental shelf and slope play an important role in the global climate system with their link to the subpolar North Atlantic Ocean circulation system and the Greenland Ice Sheet. Lately, low temperature waters on the West Greenland shelf have been observed as far south as ∼64°N and associated with a cold and relatively saline water mass originating north of Davis Strait in Baffin Bay referred to as Baffin Bay Polar Water (BBPW). Here we use long, seasonal hydrographic time series from West Greenland at ∼64°N to study how frequently BBPW is reaching this far south. The analysis covers the period 1950–2018 with a data gap between 1988 and 2005. BBPW was observed frequently and was responsible for the temperature changes observed in the late 1960s–1980s and more intermittently post‐2008. Some of the large temperature changes we observe in the time series have previously been ascribed to “Great Salinity Anomalies” (GSAs) propagating around the subpolar North Atlantic Ocean circulation system. The prevailing view of the propagation of GSAs has been ascribed to advection of anomalies along the large‐scale circulation system. Our study shows that BBPW may play an important role in the interpretation of GSAs and melt of the Greenland Ice Sheet. Large temporal temperature changes at ∼64°N are associated with arrival of BBPW from the north and not advection of anomalies with the large‐scale current system from the south. This advocates for a shift in water masses caused by changes in the position and/or strength of oceanic currents. The Greenland Ice Sheet is likely to experience significant mass losses in coming decades. One of the challenges is to understand the changing physical nature of waters on the adjacent continental shelf and their effects on tidewater glacier fjords. Lately, low temperature waters on the West Greenland shelf have been observed as far south as ∼64°N and associated with a cold and relatively saline water known as Baffin Bay Polar Water (BBPW) mass originating north of Davis Strait in Baffin Bay. We use unique, long, seasonal hydrographic time series from the West Greenland continental shelf at ∼64°N and an adjacent proglacial fjord to study how frequently BBPW is reaching this far south in the period 1953–2018. BBPW was observed at ∼64°N in the following years: 1954–1955, 1968–1976, 1980–1983, 1985, 1987, 2008, 2012, and 2015–2017. This study shows that BBPW may play an important role in the interpretation of the large‐scale subpolar North Atlantic Ocean circulation system and melt of the Greenland Ice Sheet. We present long‐term seasonal hydrographic time series from the West Greenland shelf at 64°N and adjacent proglacial fjordThe time series reveal the recurrence of Baffin Bay Polar Water (BBPW), a northern water mass originating in Baffin BayLarge temporal temperature changes are associated with arrival of BBPW and not advection of anomalies with the large‐scale current system We present long‐term seasonal hydrographic time series from the West Greenland shelf at 64°N and adjacent proglacial fjord The time series reveal the recurrence of Baffin Bay Polar Water (BBPW), a northern water mass originating in Baffin Bay Large temporal temperature changes are associated with arrival of BBPW and not advection of anomalies with the large‐scale current system

AbstractTrace nonrecycling impurities (scandium and CaF2) have been injected into Alcator C-Mod plasmas in order to determine impurity transport coefficient profiles in a number of operating regimes. Recycling Ar has also been injected to characterize steady-state impurity density profiles. Subsequent impurity emission has been observed with spatially scanning X-ray and vacuum ultraviolet spectrometer systems, in addition to very high spatial resolution X-ray and bolometer arrays viewing the plasma edge. Measured time-resolved brightness profiles of helium-, lithium-, and beryllium-like transitions have been compared with those calculated from a transport code that includes impurity diffusion and convection, in conjunction with an atomic physics package for individual line emission. Similar modeling has been performed for the edge observations, which are unresolved in energy. The line time histories and the profile shapes put large constraints on the impurity diffusion coefficient and convection velocity profiles. In L-mode plasmas, impurity confinement times are short (~20 ms), with diffusivities in the range of 0.5 m2/s, anomalously large compared to neoclassical values. During Enhanced Dα(EDA) H-modes, the impurity confinement times are longer than in L-mode plasmas, and the modeling suggests that there exists inward convection (≤50 m/s) near the plasma edge, with greatly reduced diffusion (of order 0.1 m2/s), also in the region of the edge transport barrier. These edge values of the transport coefficients during EDA H-mode are qualitatively similar to the neoclassical values. In edge localized mode-free H-mode discharges, impurity accumulation occurs, dominated by large inward impurity convection in the pedestal region. A scaling of the impurity confinement time with H-factor reveals a very strong exponential dependence. In internal transport barrier discharges, there is significant impurity accumulation inside of the barrier foot, typically at r/a= 0.5. Steady-state impurity density profiles in L-mode plasmas have a large up-down asymmetry near the last closed flux surface. The impurity density enhancement, in the direction opposite to the ion B× ΔBdrift, is consistent with modeling of neoclassical parallel impurity transport.

AbstractWe report on the results from initial testing and operation of the Columbia Nonneutral Torus, a new stellarator experiment constructed at Columbia University to study the confinement of nonneutral plasmas, electron-positron plasmas, and stellarator confinement in the presence of strong electrostatic fields. A new algorithm for automatic identification of good magnetic surfaces, island chains, and stochastic regions in Poincaré maps is also described. We present some of the details of the design of the interlocked in-vessel coils and the vacuum system and report on initial vacuum performance. Magnetic surface mapping and visualization results are also presented, confirming the existence of ultralow aspect ratio magnetic surfaces with excellent quality and good agreement with numerical calculations.

The aim of this chapter is to focus on evidence-based health economics in anaesthesia. More and more, requests for additional facilities will have to be based on detailed arguments supported by 'hard evidence' as to the gain to be expected from the patient's angle and the cost. Evidence-based clinical practice in anaesthesia isolated from economic issues is not an optimal goal. As clinicians we have to demonstrate not only the need for the use of evidence-based principles in economic evaluation, but also that such principles should themselves be based on health economics. This chapter shows how to bring economic evaluation and systematic review together, and how to use such evaluations in the clinical setting. It shows how economics can be used to broaden the evidence base for a more efficient and equitable health policy, and sets a future research agenda for this challenging area of work in Cochrane reviews dealing with anaesthesia topics.

We report on the influence of oxygen flow rate on structure, composition, density, deposition stress and optical properties of the as-deposited tantalum oxide thin films. The films were prepared by reactive direct current magnetron sputtering. The sputter current and total pressure were kept constant at 300 mA and 0.8 Pa, respectively. We could deposit fully transparent films at a rate of approximatey 6 nm/min. without noticeable substrate warming from the plasma. Grazing angle XRD showed the films to be amorphous at all oxygen flow rates. Simulations to RBS data revealed, within errors, stoichiometric films above 2 sccm oxygen flow. Moreover argon incorporation in the films above 2 sccm oxygen flow was noted. The density was found to steeply decrease upto 2 sccm followed by a very slow linear decrease with oxygen flow as deduced from X-ray reflectometry. The refractive index, the extinction coefficient and the band gap energy were all obtained by optical spectroscopy. A band gap which increased from 4.17 to 4.23 eV with oxygen flow was determined for films in the transparent region. A characteristic of the defects in the film, γ, which is obtained by simulating the optical spectra, was found to decrease from 85 meV at 6 sccm to 60 meV at 15 sccm oxygen flow. There was no significant change in γ above 15 sccm. On the other hand the refractive index and the extinction coefficient were found to slightly decrease with increasing oxygen flow for the transparent films. Stress data revealed the films to be under some compressive stress upon deposition. The stress decreased with increasing oxygen flow and stabilized at roughly –250 MPa above 6 sccm oxygen flow.

TiO2 is frequently used in optical coatings as an inexpensive material with a particularly high refractive index. Often this high refractive index is only achieved if the substrate is heated to enable the deposition of crystalline films with rutile structure. In this study titanium oxide films have been deposited by dc reactive sputtering at room temperature. The effects of oxygen flow on structural and optical properties as well as deposition stress have been investigated. The stoichiometry of the films has been determined by Rutherford backscattering spectroscopy. All films deposited in the oxidic mode at 1 Pa have been found to be amorphous, while samples prepared at 0.75 Pa and high oxygen flow have been found to be crystalline. The optical analysis showed that the optical band gap of the films prepared at 1 Pa increases while the refractive index decreases with increasing O2 flow. The variation of refractive index is related to the increase in porosity. The increase in porosity upon increasing oxygen flow has been calculated using effective medium theories. The crystalline film prepared at 0.75 Pa has a higher refractive index than the amorphous samples prepared at 1 Pa. Both the amorphous and crystalline titania films have compressive stresses of around 250 MPa.

Smoking is an important risk factor for the development of postoperative pulmonary complications after major surgical procedures. We studied 811 consecutive patients who had undergone hip or knee arthroplasty, recording current smoking and drinking habits, any history of chronic disease and such intraoperative factors as the type of anaesthesia and the type and duration of surgery. We recorded any postoperative complications occurring before discharge from hospital. There were 232 smokers (28.6%) and 579 non-smokers.We found that smoking was the single most important risk factor for the development of postoperative complications, particularly those relating to wound healing, cardiopulmonary complications, and the requirement of postoperative intensive care. A delay in discharge from hospital was usual for those suffering a complication. In those patients requiring prolonged hospitalisation (> 15 days) the proportion of smokers with wound complications was twice that of non-smokers.

Chromatin remodeling is an important step in promoter activation during cellular lineage commitment and differentiation. We show that the ability of the C/EBPalpha transcription factor to direct adipocyte differentiation of uncommitted fibroblast precursors and to activate SWI/SNF-dependent myeloid-specific genes depends on a domain, C/EBPalpha transactivation element III (TE-III), that binds the SWI/SNF chromatin remodeling complex. TE-III collaborates with C/EBPalpha TBP/TFIIB interaction motifs during induction of adipogenesis and adipocyte-specific gene expression. These results indicate that C/EBPalpha acts as a lineage-instructive transcription factor through SWI/SNF-dependent modification of the chromatin structure of lineage-specific genes, followed by direct promoter activation via recruitment of the basal transcription-initiation complex, and provide a mechanism by which C/EBPalpha can mediate differentiation along multiple cellular lineages.

AIM: To evaluate the ability of different commercially available cell culture solutions to preserve human donor corneas during 3 weeks of "closed system" organ culture at physiological temperature. This screening was performed in an attempt to establish a rational basis for the development of a serum-free organ culture medium for eye banking. METHODS: 72 normal human donor corneas were organ cultured for 21 days at 31°C in eight different test media (nine corneas in each group). The basic culture solutions included: minimal essential medium (MEM), MEM with stabilised L-glutamine, M199, DIF-1000, SFM, F99, and F99 with ascorbic acid, insulin, bFGF, transferrin, selenium, and lipids (termed F99-Sr). All media were supplemented with 2% fetal calf serum (FCS), except for MEM, which was also studied at 8% FCS. The evaluation parameters included: (1) the endothelial cell loss as evaluated using trypan blue staining; (2) the ability of keratocytes and endothelial cells to incorporate tritiated uridine into RNA as evaluated using autoradiography and digital image analysis; (3) the leakage of immunogenic keratan sulphate as assessed using ELISA; and (4) changes in storage medium pH, glucose, and lactate content. RESULTS: SFM induced the lowest endothelial cell loss of 14% (SD 2%) and the highest RNA synthesis rates of all test solutions supplemented with 2% FCS. Corneas stored in SFM also showed the least leakage of keratan sulphate and the highest glucose consumption and lactate production. In five media (MEM with 2% FCS, MEM with stabilised L-glutamine, M199, F99, and F99-Sr), comparable and intermediate potentials for organ culture were observed with endothelial cell loss of 16-19%. By contrast, 29% (4%) of the endothelium was lost after storage in DIF-1000. Interestingly, the use of 8% FCS (in MEM) had a marked protective effect on the endothelium, which showed the highest RNA synthetic activity combined with a cell loss of only 11% (4%), compared with 19% (6%) at 2% FCS (p&lt;0.05). CONCLUSION: Among the present test solutions, SFM appears to be the most prominent candidate for a new corneal organ culture medium and should be further tested and possibly refined to effectively substitute serum addition.

OBJECTIVE: To evaluate the relative impact of sex, type of onset, course of disease, age at onset, duration of disease and status of HLA-B27, antinuclear antibodies (ANA), and rheumatoid factor on the risk of developing a condylar erosion. METHODS: Condylar changes of the temporomandibular joint (TMJ) were diagnosed on orthopantomograms from 169 consecutive patients with juvenile chronic arthritis (JCA). A multiple regression analysis was applied to establish the relative weight of the independent variables affecting the severity of the condylar erosion. RESULTS: It was found that 62.1% of the patients exhibited condylar resorption. The highest prevalence was seen in children with a polyarticular onset or course of disease and early age at onset and severe resorption was also frequent in these groups. Patients with positive ANA also had a high prevalence but with a mild degree of resorption. In contrast, HLA-B27 positive patients had a lower risk of TMJ involvement and resorptive changes of the condyle. CONCLUSION: Polyarticular and early onset arthritis are associated with a high risk for TMJ involvement and a severe condylar bone loss can be expected. ANA positive patients have a high prevalence, and B27 positive patients have a low prevalence of TMJ arthritis but in both subgroups, the outcome of the bone resorptive process is mild.

The diffusion coefficients of dimethyl sulfoxide, dimethyl sulfone, ¹⁵N-labeled DNO3, and ¹⁷O-labeled D2O in solutions of 0.6−0.8 weight fraction D2SO4 in D2O were studied at temperatures from 248 to 298 K by the pulsed gradient spin-echo NMR technique. Diffusion coefficients for these compounds are reported, and an empirical technique for extrapolating the results to sulfuric acid of stratospheric compositions and temperatures is discussed. The viscosity of 0.7 weight fraction D2SO4 in D2O at temperatures from 248 to 298 K is also reported.

As part of the Danish NEAREX project a three-dimensional Eulerian hemispheric air pollution model is used to study the transport and concentrations of atmospheric CO2in the North East Atlantic region. The model domain covers the major part of the Northern Hemisphere and currently the model includes simple parameterizations of the main sinks and sources for atmospheric CO2. One of the objectives of the project is to study and maybe quantify the relative importance of the various sinks and source types and areas for this region. In order to do so the model has been run with differentiated source types. Here the model setup and the used parameterizations will be described. The model is validated by comparing the results with atmospheric measurements from four monitoring stations in or close to the northern part of the North Atlantic. Some preliminary model results will be shown and shortly discussed.

.Purpose:
To describe the technique of grafting only the posterior cornea and to report 12-month clinical results.
Method:
A two-layer technique with an anterior recipient flap created by a microkeratome and a posterior penetrating donor graft allows for a watertight wound closure and at the same time a peroperative correction of astigmatism. Four eyes (3 patients) were followed for 12 months.
Results:
The surgical technique could be completed in all cases without complications. The postoperative course was uneventful. The intrastromal absorbable sutures disappeared spontaneously and completely. Graft thickness showed the expected 6-month minimum while recipient flap thickness remained constant. After 1 year endothelial cell densities were 1200-2300 cells/mm². Confocal microscopy showed activated keratocytes in the flap and quiescent keratocytes in the donor tissue by one year. The anterior chamber depth was normal in all cases. The optical quality of the cornea was studied by automatic keratometry and keratoscopy (TMS). The obtained optical properties were not optimal.
Conclusions:
The developed novel technique gives a better wound closure and a complication free postoperative course. It may allow for better control of postoperative astigmatism. In order to disseminate the use of the technique, eyebanks should supply posterior corneas to the surgeon.

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A racemic aldehyde can undergo parallel kinetic resolution (PKR) by simultaneous reaction with two different chiral phosphonates, differing either in the structure of the chiral auxiliary or in the structure of the phosphoryl group (i.e., one (E)- and one (Z)-selective reagent). This strategy allows conversion of a racemic aldehyde to two different, synthetically useful chiral products with essentially doubled material throughput and similar or improved selectivities as compared to conventional kinetic resolution.