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The influence of small amounts of added HCl during MOVPE growth of GaN and AlN in a hot-wall reactor is investigated. It is observed that parasitic precursor losses in the gas phase are suppressed, enabling crystal growth with large growth rates at elevated pressures. For the growth of GaN, only a small ratio of HCl to TMGa is necessary. This ratio is independent of the total TMGa flow rate but rises with increasing reactor pressure. For too high HCl-to-TMGa ratios, a reduced growth rate of GaN is observed. For the growth of AlN, a much higher HCl-to-TMAl ratio is needed. At this condition the same growth rate with a uniform deposition profile at a quadrupled reactor pressure is achieved, for otherwise unchanged flow conditions.

Urbane Gebiete sind ein Brennpunkt von Konflikten zwischen Wassernutzung und Wasserschutz. Die Halfte der Weltbevolkerung und ca. 73 % der europaischen Einwohner leben gegenwartig in Stadten. Ungefahr 82 % des Zuwachses der Weltbevolkerung geschieht in den Stadten der Entwicklungslander (UN 2004). Urbane Wassersysteme werden zunehmend mit organischen Kontaminanten als direkte und/oder indirekte Konsequenz anthropogener Einflusse verschmutzt. Viele der im Wasser nachgewiesenen Kontaminanten, wie z. B. pharmazeutische Stoffe und Korperpflegemittel (im englischen: pharmaceuticals and personal care products – PPCP) und endokrin wirksame Substanzen, entstammen alltaglichen menschlichen Aktivitaten. Das Verhalten und die Effekte dieser Kontaminanten in der Umwelt sind bisher weitgehend unbekannt. Deshalb ist es wichtig, das Risiko ausgehend von urbaner Wasserverschmutzung im Hinblick auf solche Substanzen umfassend zu untersuchen. Ziel sollte es sein, neue integrierte Strategien (einschlieslich Massenflussberechnungen, chemischer und biologischer Untersuchungen) zur Bestimmung der Auswirkungen menschlicher Aktivitaten auf das urbane Wassersystem und der Prozesse im urbanen Einzugsgebiet zu entwickeln. Damit soll das Risiko fur den Menschen und das Okosystem abgeschatzt und die Entwicklung geeigneter Managementstrategien unterstutzt werden.

Xenobiotika werden zunehmend als okotoxikologisch relevant fur die aquatische Umwelt und den Menschen angesehen. Das Verhalten und die Auswirkungen dieser Stoffe in der Umwelt sind bisher nur wenig umfassend untersucht worden und werden deshalb im Rahmen des Projektes WASSER Leipzig durch das UFZ in einem urban gepragten Einzugsgebiet bearbeitet. Dieser Artikel stellt erste Analysen des Grund- und Oberflachenwassers vor. Es wurden die Gehalte der Industriechemikalien Bisphenol A und t-Nonylphenol, der polyzyklischen Duftstoffe Galaxolid und Tonalid, des antiepileptischen Medikaments Carbamazepin sowie von Koffein bestimmt, die ein ubiquitares Vorkommen zeigten. In den Vorflutern wurden mittlere Konzentrationen von bis zu einigen 100 ng/l gemessen, die auf den Einfluss geklarter aber auch ungeklarter Abwasser zuruckgefuhrt werden konnen. Im Grundwasser zeigten sich bis auf Bisphenol A geringere Werte. Die Belastung des Grundwassers ist auf Abwasserleckagen aus der Kanalisation zuruckzufuhren. Mithilfe einer Faktorenanalyse der hydrochemischen Messwerte lassen sich die Xenobiotika hinsichtlich ihres hydrochemischen Verhaltens im Grundwasser differenzieren.

Direct aluminum bonded (DAB) substrates have been developed. They can serve as isolating carriers especially for power electronic circuits or integrated components, respectively, using the standard assembly processes also applied to state of the art direct copper bonded (DCB) substrates. This new type of substrates has been characterized theoretically based on material properties of its layers and experimentally. While it behaves similar to DCB in many respects, the remarkably higher temperature cycling capability of DAB substrates constitutes a major difference, which is also useful to increase reliability of components exposed to extreme environmental temperatures. DAB based moulded integrated components with large chips in this respect have shown to reach a level of reliability which could not be achieved earlier with conventional technology. Outperforming the latter and complementing DCB, DAB can thus, in the future, be expected to explore new, and contribute to optimization of, existing applications with special demand for high reliability or also low weight. This makes this material well suited for use, e.g., in automotive power converters or avionic electronics

Thin films of Tris(8-hydroxyquinoline)-aluminum(III) (Alq3) and N,N′-Di-[(1-naphthyl)-N,N′-diphenyl]-(1,1′-biphenyl)-4,4′-diamine (α-NPD ) were deposited on large-area silicon substrates by means of the recently developed organic vapor phase deposition (OVPD) method. Variable-angle spectroscopic ellipsometry was used to measure the optical constants of OVPD Alq3 and α-NPD layers in the 0.8–5 eV energy range. The absorption onset which defines the lower limit of the optical band gap was found to be at ∼2.65 eV and ∼2.9 eV for Alq3 and α-NPD , respectively. Additionally, the thicknesses of the layers as well as the thickness profiles of the organic thin films were determined along the 8′′ diameter of the wafers. The thickness analysis revealed large-area uniform deposition of the films.

Contamination of the urban aquatic environment with chemical and biological substances could have a long-term impact on human health because these substances threaten the integrity of the urban ecosystem and the availability of high-quality water for recreation and consumption. In light of this, the aim of the present study was to assess the potential immunological effects of water sampled at various sites along the River Saale near the city of Halle (in the state of Sachsen-Anhalt, Germany). For the control, Ficoll-separated peripheral blood mononuclear cells (PBMC) of healthy donors were cultured for 24 h in either filter-sterilized river water or drinking-water samples. Cell vitality was assessed using the MTT bioassay. Cytokines in culture supernatants were measured by ELISA. Endotoxin concentrations in the water samples were assessed by the limulus amoebocyte lysate (LAL) test. River water and drinking water showed comparably weak cytotoxic effects on PBMC. Drinking water did not exert any effect on cytokine secretion. In contrast, all river-water samples triggered secretion of proinflammatory cytokines, as shown for TNF-α, IL-1β, and IL-6. Free endotoxin was detected in all river-water samples. However, the highest inflammatory activity regarding induction of all three cytokines, as well as the highest endotoxin content as determined by LAL, was found in a water sample taken immediately downstream of a wastewater treatment plant. Inhibition studies using the monoclonal anti-CD14 antibody biG14, which is known to suppress binding of lipopolysaccharide (LPS) to CD14 via binding CD14 itself, revealed that free endotoxin was indeed the major inducer of proinflammatory cytokines in the river-water samples. Taken together, the results suggest that the microorganism-derived endotoxin is a widely distributed contaminant in the urban aquatic environment that should be considered in routine monitoring and in assessing ecosystem and human health. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 594–602, 2004.

The available range resolution of pulsed radar wind profilers is usually limited by bandwidth restrictions. Range imaging (RIM) has recently been developed as a means of mitigating these limitations by operating the wind profilers over a small set of distinct transmitter frequencies. A constrained optimization method can then be used to generate high-resolution maps of the reflectivity field as a function of range. This paper presents a description of how the RIM technique has been recently implemented on the Platteville 915-MHz tropospheric profiler, the first such implementation at UHF. Examples of data collected during a two-part experiment on 10 April 2001 using the Platteville 915-MHz tropospheric profiler are presented. In the first part, an intercomparison was made involving measurements from RIM and standard radar techniques. It is shown that available frequency bandwidth can be very effectively utilized through the RIM processing. In the second part of the experiment, RIM was applied to radar observations collected with a short (0.5 ms) transmit pulse. The resulting data include observations of a thin, persistent scattering layer attributed to a subsidence inversion and billows from a Kelvin‐ Helmholtz instability. Estimates of the width of the layer were found to be as small as 12 m.

Heavy-metal removal from a toxic waste depository in East Germany occurs through the action of bacterial scavenging, as contaminant-laden waters transit a bounding dam. Measurements inside and outside the toxic domain indicate that this removal can amount to more than 90% of particular heavy metals from the exiting waters. This paper examines the steady-state behavior of interconnected bacterial number density dependence on the heavy-metal concentration, removal of the bacteria by heavy-metal poisoning, and simultaneous removal of the heavy metals by bacterial scavenging. Adjustment of the birth and death rates of bacteria, together with a propensity for the bacteria to seek out and scavenge the richest zones of heavy-metal contamination in the waters seeping through the dam, are the main intertwined components that allow heavy-metal removal.There is also a critical concentration such that bacteria cannot scavenge in waters with heavy metals above the critical concentration; the closeness of the input concentration to the critical value at the toxic side of the bounding dam plays a significant role in the spatial distribution of heavy-metal removal and also in bacterial number density concentration. Measurements both inside and outside the toxic depository allow one to bracket combinations of some of the biological parameters to account for the observations, but there are no uniquely determined values; such would require measurements in the dam materials. For a variety of health-risk reasons, such dam probes are not likely to be allowed in the near future, so that the determinations are limited.

An algorithm to compute the magnitude of humidity gradient profiles from the measurements of the zeroth, first, and second moments of wind profiling radar (WPR) Doppler spectra was developed and tested. The algorithm extends the National Oceanic and Atmospheric Administration (NOAA)/Environmental Technology Laboratory (ETL) Advanced Signal Processing System (SPS), which provides quality control of radar data in the spectral domain for wind profile retrievals, to include the retrieval of humidity gradient profiles. The algorithm uses a recently developed approximate formula for correcting Doppler spectral widths for the spatial and temporal filtering effects. Data collected by a 3-beam 915-MHz WPR onboard the NOAA research vessel Ronald H. Brown (RHB) and a 5-beam 449-MHz WPR developed at the ETL were used in this study. The two datasets cover vastly different atmospheric conditions, with the 915-MHz shipborne system probing the tropical ocean atmosphere and the 449-MHz WPR probing continental win...

Platinum (Pt), ruthenium (Ru), and ruthenium dioxide (RuO 2 ) have been considered as possible candidates as electrodes for high permittivity and ferroelectric oxides. The films were grown by metal organic chemical vapor deposition (MOCVD). High purity Pt films with near bulk resistivities (11 w z cm) were deposited. The Pt, Ru and RuO 2 films were found to be continuous and smooth and exhibited excellent adhesion properties on the underlying substrates. The temperature dependent electrical conductivity of the Ru and RuO 2 films was metallic type. Room temperature resistivities as low as 18 and 30 w z cm were determined for Ru and RuO 2 , respectively.

We report on a new planetary hotwall research system with independent control of the ceiling and susceptor temperatures. This allows a study of the influence of an actively heated ceiling during a MOCVD process. It was found that the temperature profile across the substrate becomes more uniform when the ceiling temperature is increased while maintaining the same susceptor surface temperature. The parasitic coating on the ceiling was found to be stable and no source of particles up to 1050 °C. The influence of the ceiling temperature on the depletion profile and the possibility to manipulate it was investigated. Good thickness homogeneity of 1.35% (1·σ) on a 4″ sapphire wafer was achieved with excellent XRD results of 206 arcsec for the (0002) reflex and 272 arcsec for the (10-12) reflex for a 4.7 µm thick GaN film. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In the Mansfeld region (Central Germany) copper mining contributed to an enormous pollution of the environment. Metal- and sulphate-bearing sediments and leachates emerge from the former copper smelters and mining waste heaps, spread along local rivers and finally reach the Saale river. A sulphur isotope study on water and stream sediments was performed along the River "Böse Sieben" and from its tributaries to determine the different sulphur sources. Four major sulphur sources exist in the area: metal sulphide mineralisations (Kupferschiefer), met alliferous sulphidic flue dust, slag, and anhydrite and gypsum of Permian and Triassic age. We obtained delta34S(SO4)-values in water samples varying from +4 per thousand to -18 per thousand CDT, clearly reflecting the input of sulphate from different sources. Sulphate from the oxidation of sulphidic mining residues is restricted to the mining area and cannot be traced for more than 5 km downstream. The major source for sulphate is the dissolution of gypsum and anhydrite. The sulphur isotope composition in dissolved and sedimentary adsorbed sulphate differs only slightly from each other. Microbial dissimilatory sulphate reduction can not be excluded in the shallow sediment layers.

MOCVD (metal–organic chemical vapor deposition) of new materials, such as perovskite-type ceramic thin films, will be a major key technology in the field of ULSI non-volatile and volatile memory applications. This article outlines the latest trends in the field of MOCVD equipment and process development, in particular in the field of high k-dielectric and ferroelectrics. Using liquid precursor delivery systems reproducible evaporation can be achieved. Furthermore, perfect temperature control, as well as a precise gas and vapor flow control through the gas inlet to the substrate, ensure high quality BST, PZT and SBT thin films, bearing superior electrical and microstructural properties and near 100% step coverage at low process temperatures. Copyright © 2000 John Wiley & Sons, Ltd.

Silicon Carbide is presently gaining much attention as a material for high temperature, high speed and high power devices. However, fabricating epitaxial SiC or GaN films is still a challenge since very high growth temperatures (up to 1600°C) must be used. This requires a carefully adapted design of reactors to ensure laminar flow conditions and a controlled depletion of the reactants inside the reactor. A second class of materials that is also playing a more and more important role today are the III nitrides (AIN, GaN, InN and alloys consisting of these). These materials are also grown at high deposition temperatures (up to 1300°C). Furthermore, these materials are grown on special buffer layers grown at much lower temperatures and are typically part of complex heterostructures which require abrupt changes of the growth temperature to realize sophisticated optoelectronic and electronic devices. As an example our high quality InGaN layers were grown at about 700°C and the AIGaN cladding layer of a laser or a LED require temperatures higher than 1100°C. In general, both nitrides and SiC are similar in their challenges to the growth equipment. This study uses a family of high temperature reactors to grow SiC and Nitrides. We describe the use of high temperature reactors to grow SiC and Nitrides. The load capacity ranges from single wafer machines to multiple wafer mass production reactors. All these reactors have a two flow injection system allowing a separated inlet of the various reactants. To achieve maximum uniformity of the growth, the Gas Foil Rotation (r) Principle is applied. The multiwafer reactors are Planetary Reactors with double rotation of substrates. Extensive modeling has been used in order to find the optimum reactor geometries. Gas flow dynamics, temperature management and the physical and chemical properties of the precursors were considered in these models. Thus an optimization of uniformity and efficiency and a minimization of undesired parasitic reactions has been obtained. This contribution will work out the differences and the similarities of the high temperature growth of both material systems in AIXTRON reactors already established in production. Results on the growth of SiC and GaN will be presented.

The mucosal lymphocyte integrin αE(CD103)β7 is thought to be important for intraepithelial lymphocyte (IEL) localization or function. We cloned the murine integrin gene encoding αE, localized it to chromosome 11, and generated integrin αE-deficient mice. In αE−/− mice, intestinal and vaginal IEL numbers were reduced, consistent with the known binding of αEβ7 to E-cadherin expressed on epithelial cells. However, it was surprising that lamina propria T lymphocyte numbers were diminished, as E-cadherin is not expressed in the lamina propria. In contrast, peribronchial, intrapulmonary, Peyer’s patch, and splenic T lymphocyte numbers were not reduced in αE-deficient mice. Thus, αEβ7 was important for generating or maintaining the gut and vaginal T lymphocytes located diffusely within the epithelium or lamina propria but not for generating the gut-associated organized lymphoid tissues. Finally, the impact of αE deficiency upon intestinal IEL numbers was greater at 3–4 wk of life than in younger animals, and affected the TCR αβ+ CD8+ T cells more than the γδ T cells or the TCR αβ+ CD4+CD8− population. These findings suggest that αEβ7 is involved in the expansion/recruitment of TCR αβ+ CD8+ IEL following microbial colonization. Integrin αE-deficient mice will provide an important tool for studying the role of αEβ7 and of αEβ7-expressing mucosal T lymphocytes in vivo.

Radar wind profilers (RWPs) sense the mean and turbulent motion of the clear air through Doppler shifts induced along several (3–5) upward-looking beams. RWP signals, like all radars signals, are often contaminated. The contamination is clearly evident in the associated Doppler spectra, and automatic routines designed to extract meteorological quantities from these spectra often yield inaccurate results. Much of the observed contamination is due to an aliasing of higher frequency signals into the clear-air portion of the spectrum and a broadening of the spectral contaminants caused by the relatively short time series used to generate Doppler spectra. In the past, this source of contamination could not be avoided because of limitations on the size and speed of RWP processing computers. Today’s computers, however, are able to process larger amounts of data at greatly increased speeds. Here it is shown how standard and well-known spectral processing methods can be applied to significantly longer tim...

Metalorganic chemical vapor deposition (MOCVD) has been established as the most favoured method for the processing of (Ba, Sr)TiO3, Pb(Zr, Ti)O3 and SrBi2Ta2O9 thin films. Due to good step coverage, uniformity of thickness and composition as well as throughput MOCVD will certainly be the choice for the mass production of future electroceramic thin film based devices such as volatile and non-volatile memories, electrooptic devices, microactuators and sensors. Since many groups showed in a laboratory scale that electroceramic thin films deposited by MOCVD techniques are suitable for future applications in terms of electrical and mechanical properties, the need for production worthy tools is rapidly increasing. In this paper we present a large scale manufactor tool (capacity up to 4 × 300 mm) which meets all demands for an automized mass production of electroceramic thin films.

Simulations of weather radar echoes were used to determine whether single-pulse estimates of velocity could be made with sufficient accuracy to measure the velocity aliasing that is inherent with pulse Doppler weather radars. The results indicated that this type of velocity measurement can be made, but such a large number of single-pulse estimates need to be averaged to determine the velocity aliasing that the concept is not compatible with the spatial and temporal resolution requirements of the WSR-88D (NEXRAD).

It is well known that the presence of ground clutter may severely bias radar measurements of the Doppler shift, particularly with wind profilers undertaking boundary layer measurements. It is shown both qualitatively and quantitatively with simulated data that a simple detrending of the time series data is often sufficient to significantly reduce the clutter problem. Finite impulse response filters are also investigated. Improvements are seen when long records are filtered prior to spectral analysis of the time series. The results are not very sensitive to the width of the filter (within reason) as long as the filter width encompasses the clutter spectrum.

For the fabrication of epitaxial films of silicon carbide or the Group III nitrides, high growth temperatures (up to 1700°C) and fast heating and cooling of the growth environment have been found to be necessary. A range of production systems meeting these requirements has been designed with different loading capacities. In this paper, we present results from various machines showing the high quality and excellent homogeneity obtainable for 3C-SiC on Si and on 6H-SiC, as well as GaN on sapphire.

The isotopic and chemical composition of water and dissolved sulfur and carbon compounds from a flooded lignite-mining lake and a dump site in Central Germany (today partly covered by a landfill) is used to investigate the sulfate reduction and degradation process of organic matter in the lake and the groundwater. The isotopic composition of both the sulfate/sulfide and the dissolved inorganic carbon (DIC) confirm similarities between the processes in the subhydrical landfill site and in the anaerobic zone of the lake (monimolimnion). The strong reducing conditions are expressed by an enrichment of δ34S of sulfate (landfill: δ34S-SO4 = +37ℵ, bottom of the lake: δ34S-SO4 = +27ℵ), despite varying sulfate supply. More than 50% of the sulfate in the landfill and up to 95% of the sulfate in the monimolimnion were calculated to have been reduced according to the Rayleigh relation. The carbon isotopic composition of DIC ranges from δ13C = -10ℵ to δ13C = -19ℵ in the landfill and from δ13C = -8ℵ to δ13C = -18ℵ in the lake. It was shown that these values represent the complex interactions between the production of methane and carbon dioxide and the formation of bicarbonate from intermediate products.

The need for ferroelectric capacitors and FRAMs is rapidly increasing as world wide communication networks are being erected and a higher integration of memory chips will be introduced in the next few years. To meet the demand for economical production of the raw material - thin film structures of ferroelectrics - we developed a metalorganic vapor phase epitaxy (MOVPE) reactor for the deposition of the material films on a large substrate area. We expanded the existing Planetary Reactor® to be able to take charges of nine six inch wafers or the equivalent (total substrate area of 0.25 square meters). The growth process can be predicted by numerical simulations rather than by growth runs in the real reactor. The reactor is proven in mass production environments for the growth of multicompound semiconductors. A major achievement is the compensation of the depletion of the gas phase which can result in poor uniformity of the films. By rotating the wafers, the growth rate along the direction of flow i...

In this study a range of MOVPE systems for high temperature epitaxial growth processes, such as SiC and group III nitrides, is presented. It is shown that extensive modelling of the heat transfer, gas flow and reactant depletion has led to highly efficient reactors that provide the capability for uniform growth of binary and ternary material systems at temperatures up to 1600 C in single- and multi wafer configurations. Experimental results of various layers are presented to prove the availability of state-of-the-art process technology in production-scale systems.

The worldwide demand for ultra-high-brightness blue and green LEDs has driven the development of MOCVD for Al-Ga-In-N alloy systems towards efficient multiwafer technology. This new MOCVD approach has been developed using a unique growth initiation cycle which provides material of superior quality and increased lateral thickness uniformities in the 7 in × 2 in to 15 in × 2 in Planetary Reactor ® , which is to our knowledge the largest Nitride MOCVD reactor in the field of successful production of blue LEDs. For proper growth initiation for blue-green LED material it is essential that heating from room temperature to 1000 °C can be done in less than 2 min and the cool down from 1000 to 500 °C takes place in 3 min. The growth initiation cycle has been demonstrated to yield device quality GaN with X-ray FWHM of 30 arcsec and excellent PL uniformity. The key to the excellent results is the high flexibility of this unique MOCVD process which can be used between 10 and 1000 mbar, a variety of total flow rates and extremely precise temperature control and uniformity across the entire reactor and the substrates. Using all these flexible parameters in the appropriate way allows the required growth rate to be adjusted and the necessary control on In composition in InGaN with the successful demonstration of blue LEDs to be obtained.

Copyright (c) 1997 Elsevier Science S.A. All rights reserved. The worldwide demand for ultra-high-brightness blue and green light emitting devices (LEDs) has driven the development of metalorganic chemical vapor deposition (MOCVD) for Al−Ga−In−N alloy systems towards efficient multiwafer technology. This new MOCVD approach has been developed using a unique growth initiation cycle which provides material of superior quality and increased lateral thickness uniformities in the 7×2 to 15×2 Planetary Reactor®, which is to our knowledge the largest Nitride MOCVD reactor in the field of successful production of blue LEDs. The MOCVD process, based on a laminar radial two-flow approach will be discussed in detail. The design provides material with abrupt interfaces, also while using different substrates like Al 2 O 3 , SiC, Si. Wafer rotation is performed by means of Gas Foil Rotation®. For proper growth initiation for blue-green LED material it is essential that heating from room temperature to 1000°C can be done in less than 2 min and the cool down from 1000 to 500°C takes place in 3 min. The growth initiation cycle has been demonstrated to yield device quality GaN with X-ray full width at half maximum (FWHM) of 30 arcsec and excellent photoluminescence (PL) uniformity. Key to the excellent results is the high flexibility of this unique MOCVD process that can be used between 10 and 1000 mbar, a variety of total flow rates and extremely precise temperature control and uniformity across the entire reactor and the substrates, by means of a new multicoil heater system. Using all these flexible parameters in the appropriate way allows to adjust the required growth rate and to obtain the necessary control on In composition in InGaN with the successful demonstration of blue LEDs.

International audience; Although regular physical activity is an integral part of T2D management, few diabetic patients have a sufficient level of physical activity. However over the past decade or so, the beneficial effects of regular physical activity have been well demonstrated, both in T2D prevention (50% reduction in the incidence of T2D in subjects with high metabolic risk) as well as T2D management for the improvement of glycaemic control (mean 0.7% improvement of HbA(1c)) and the reduction of T2D-related comorbidities (improvement in blood pressure values and lipid profile, decrease in insulin resistance). Physical activity has both acute effects (effects of one exercise session) and more prolonged effects of exercise when it is repeated on a regular basis (training effect). In addition, the physical activity recommendations have been extended to a wide range of physical activities (by combining both endurance and muscle strengthening exercises), thus varying the physical activity practiced according to the patient's available time, practice sites, preferences and interests. Following a pathophysiology review, the effects of physical activity will be discussed and presented in terms of evidence-based medicine. The recommendations will be defined and practical prescribing information will be suggested, while taking into account that clinicians are concerned with answering questions regarding how, where and with whom: how can patients be motivated to practice a physical activity over the long-term? And how can qualified exercise trainers and appropriate practice settings be found? (C) 2013 Elsevier Masson SAS. All rights reserved.

The groundwaters studied and labelled as mineral water were “natural mineral waters” for bottled waters and “natural curative waters” for heal therapeutical applications. They were characterized either by a specific mineralization or their suitability for balneology. To reveal the actual hydrological situation isotope investigations using 2H, 18O, 3H, 12C and 14C (DIC) and 34S (sulphate) were included in a study describing samples of 24 mineral water deposits in Saxonia. The water was classified into 4 hydrochemical types of genesis. Due to different hydrogeological and hydrochemical situations widely scattered isotope ratios were measured. Most of the investigated mineral waters are containing at least parts of younger waters (with residence times less than about 40 years). Correlations between chemical composition and the tritium content could be observed within different springs from the areas Bad Brambach, Bad Elster and Burkhardswalde. Strong variations in δ34S were found in samples with low...

Asthma is a chronic disease, which affects patients' daily lives. The goal of this study was the development of a disease-specific scale to evaluate quality of life in asthmatic patients in France: The Asthma Impact Record Index (AIR Index). The study was conducted with the participation of 486 asthmatic patients using the following steps: 1) selection of dichotomous items; 2) reduction of the number of items; 3) study of reproducibility of the questionnaire; 4) weighting of items; 5) study of the reliability and validity of the final version of the AIR Index. The final version of the AIR Index contains 63 unweighted items. The items were classified into subscales representing the main dimensions of quality of life: 1) physical, which was itself split into two subscales: a) physical activities; and b) symptoms; 2) psychological; and 3) social or relational. The internal consistency, measured by Cronbach's alpha coefficients, was found to be high, for the global scale and all subscales (range 0.79-0.94). The concurrent validity, evaluated by studying the relationship between the score values on the global scale and the subscales, and the parameters reflecting disease severity, was also high. We conclude that the AIR Index might represent a useful evaluative and discriminant instrument in studying quality of life in asthma in French populations.

A new technique for the sample preparation, directly coupled to an isotope ratio mass spectrometer (IRMS) for D/H determination, is described. The method is suitable for the preparation of fresh and saline waters as well as different organic compounds (gaseous or liquid). One microliter of water or hydrogen equivalent is injected and reduced by means of chromium metal in a specially designed reaction furnace, and then the hydrogen gas flows directly into the IRMS to be analyzed by standard/sample comparison. The reproducibility is about 1‰. The accuracy of this method is confirmed by analysis of IAEA standard waters VSMOW, GISP, and SLAP. All aqueous samples including liquid food samples as well as methane gas were injected as original compounds and directly measured without any preparation.

Currently, there is no widely accepted structured representation of drug prescription. Nevertheless, a structured representation is required for entering and storing drug prescriptions avoiding free text in computerized systems, and for drug prescription reviews. Derived from part of the work of the European OPADE project, we describe an object-oriented model of drug prescription which incorporates important concepts such as the phase and triggering event concepts. This model can be used to record all drug prescriptions, including infusions, in a structured way avoiding free text. The phase concept allows the storage of sequentially ordered dosage regimens for a drug within the same prescription. The prescription triggering event concept allows recording of the administration of a drug conditional to dates, symptoms and clinical signs, medical procedures, and everyday life events. This model has been implemented within the OPADE project; the corresponding aspects of the user interface are presented to show how this model can be used in practice. Even if other new attributes may be added to the described objects, the structure of this model is suitable for general use in software which requires the entry, storage and processing of drug prescriptions.

Wind-profiling Doppler radars measure the radial component of motion in the “clear atmosphere” along the radar beam. At lower VHF (e.g., 50 MHz) the backscattering process is highly anisotropic with maximum returns from stable layers near vertical incidence. By contrast, at UHF the backscattering process is very nearly isotropic. Because of these differences in scattering mechanism it is of interest to intercompare vertical velocities measured by collocated profilers, one operating at lower VHF and the other at UHF. An observational campaign was undertaken at Platteville, Colorado, to intercompare vertical motions measured by two collocated profilers. The VHF (50 MHz) wind profiler was operated in a vertical-only mode interrupted every half hour for radio accoustic sounding system (RASS) measurements. The UHF (404 MHz) profiler was operated in low and high modes that are customary for the Demonstration Network of profilers in the central United States. Observations made by these two systems in October and November 1991 are intercompared. The overall agreement in vertical motions is quite good above 8 km with both profilers showing downward mean velocities in the lee of the Colorado Rocky Mountains as large as 6 cm s−1. Below 8 km the UHF velocities are systematically more downward than the VHF velocities. This systematic difference is attributed to the influence of hydrometeors on the UHF observations, as can be seen clearly in daily and hourly profiles.

Winds measured with 915- and 404-MHz wind profilers are frequently found to have nonrandom errors as large as 15 m s−1 when compared to simultaneously measured rawinsonde winds. Detailed studies of these errors which occur only at night below about 4 km in altitude and have a pronounced seasonal pattern, indicate that they are due to the wind profilers' detection of migrating songbirds (passerines). Characteristics of contaminated data at various stages of data processing are described, including raw time series, individual spectra, averaged spectra, 30- or 60-s moments, 3- or 6-min winds, and hourly averaged winds. An automated technique for the rejection of contaminated data in historical datasets, based on thresholding high values of rnoment-level reflectivity and spectral width, is shown to be effective. Techniques designed for future wind profiter data acquisition systems are described that show promise for rejecting bird echoes, with the additional capability of being able to retrieve the t...

We assessed the effect of ketoprofen and prednisolone on the complement receptors (CR1 and CR3) and Fc gamma RIII expression on polymorphonuclears in an ex vivo study, using a randomized, single- blind, placebo-controlled, parallel design. Twenty-four healthy, male, Caucasian volunteers received either oral ketoprofen 100 mg twice daily, or prednisolone 5 mg twice daily, or placebo twice daily for 7.5 days. CR1, CR3 and Fc gamma RIII on unstimulated and FMLP-, C5a-, LTB4-, and GM-CSF-stimulated neutrophils were assessed using specific monoclonal antibodies and flow cytometry. No statistically significant drug effect was found for CR1, CR3, and Fc gamma RIII expression on polymorphonuclears. An in vitro study also yielded negative results. These findings do not support the hypothesis that the effect of non- steroidal antiinflammatory drugs on neutrophils is due to CR1, CR3, or Fc gamma RIII modulation.

Temperature measurements made with a 50-MHz wind profiler equipped with a radio acoustic sounding system (RASS) are compared with radiosonde observations (raobs) during a 5-week period in the fall of 1991. The accuracy of the RASS temperature measurements corrected for vertical air motion is reported. Measurements made during a period when vertical air motion was observed showed a mean improvement of 0.7°C after correction. The rms differences between the RASS observations and the raobs showed improvement at all the measurement heights when the correction for vertical air motion was made. The accuracy for all the observations is reported to be 0.9°C. The remaining differences in the temperature are compared with a model of RASS errors induced by horizontal winds and turbulence.

The groundwaters studied and labelled as mineral water were "natural mineral waters" for bottled waters and "natural curative waters" for heal therapeutical applications. They were characterized either by a specific mineralization or their suitability for balneology. To reveal the actual hydrological situation isotope investigations using (2)H, (18)O, (3)H, (12)C and (14)C (DIC) and (34)S (sulphate) were included in a study describing samples of 24 mineral water deposits in Saxonia. The water was classified into 4 hydrochemical types of genesis. Due to different hydrogeological and hydrochemical situations widely scattered isotope ratios were measured. Most of the investigated mineral waters are containing at least parts of younger waters (with residence times less than about 40 years). Correlations between chemical composition and the tritium content could be observed within different springs from the areas Bad Brambach, Bad Elster and Burkhardswalde. Strong variations in δ(34)S were found in samples with low sulphate content, showing different sulphur sources, as well as microbiological reactions. On the other hand mineral waters from Bad Brambach and Bad Elster show nearly the same δ(34)S value of about 6‰ CDT despite beeing of a different chemical type. The δ(13)C values between -22 and -2.2y PDB are related to different sources of CO(2).

Several ground-based remote sensors were operated together in Colorado during February and March 1991 to obtain continuous profiles of the kinematic and thermodynamic structure of the atmosphere. Instrument performance is compared for five different wind profilers. Each was equipped with Radio Acoustic Sounding System (RASS) capability to measure virtual temperature. This was the first side-by-side comparison of all three of the most common wind- profiler frequencies: 50, 404, and 915 MHz. The 404-MHz system was a NOAA Wind Profiler Demonstration Network (WPDN) unit. Dual-frequency microwave radiometers that measured path-integrated water vapor and liquid water content were also evaluated. Frequent rawinsonde launches from the remote-sensor sites provided an extensive set of in situ measurements for comparison. The winter operations provide a severe test of the profiler/RASS capabilities because atmospheric scattering is relatively weak and acoustic attenuation is relatively strong in cold, dry conditions. Nevertheless, the lower-frequency systems exhibited impressive height coverage for wind and virtual temperature profiling, whereas the high-frequency units provided higher-resolution measurements near the surface. Comparisons between remote sensor and rawinsonde data generally showed excellent agreement. The results support more widespread use of these emerging technologies.

The assessment of micropollutants in the urban aquatic environment is a challenging task since both the water balance and the contaminant concentrations are characterized by a pronounced variability in time and space. In this study the water balance of a central European urban drainage catchment is quantified for a period of one year. On the basis of a concentration monitoring of several micropollutants, a contaminant mass balance for the study area's wastewater, surface water, and groundwater is derived. The release of micropollutants from the catchment was mainly driven by the discharge of the wastewater treatment plant. However, combined sewer overflows (CSO) released significant loads of caffeine, bisphenol A, and technical 4-nonylphenol. Since an estimated fraction of 9.9-13.0% of the wastewater's dry weather flow was lost as sewer leakages to the groundwater, considerable loads of bisphenol A and technical 4-nonylphenol were also released by the groundwater pathway. The different temporal dynamics of release loads by CSO as an intermittent source and groundwater as well as treated wastewater as continuous pathways may induce acute as well as chronic effects on the receiving aquatic ecosystem. This study points out the importance of the pollution pathway CSO and groundwater for the contamination assessments of urban water resources.

This paper reports a new study of LP-MOVPE process for multiwafer applications in ternary GaInP alloys, rivalling substitution or adding to AlGaAs in a variety of applications, such as HBTs, lasers, LEDs or solar cells. Rising demand for these consumer applications has been driving the development of GaInP multiwafer reactors with high volume throughput. The low pressure planetary reactor has been used in this investigation. It has the capability to grow on multiple wafers at the same time for qualification, characterization or device processing. This eliminates uncertainties from single wafer reactors and allows absolute identical growth conditions for different substrates in the same run for studies of substrate effects.

Networks of radars that point almost vertically and continuously measure the vertical profile of the horizontal wind will, in the future, be operated at many locations around the world. Although such radars are designed to measure the Doppler-sensed movement of clear-air refractive-index inhomogeneities, they are an exceptional tool for sensing precipitating ice and water particles in clouds. Because of the low detection threshold and long averaging time of these radars water-particle-size distributions can be measured down to 100-µm diameter and mean vertical fall velocities Vf as small as 0.2 m s−1 can be accurately measured. In this paper, data are presented from two events in which clouds form, intensify, and finally produce precipitation. Height profiles are analyzed in terms of ZRVf plots versus height, where Z is the radar reflectivity factor and R is liquid flux (rainfall rate). The observations provide new insight into drop-growth and breakup processes. Special attention is given to the ...

The effect of azelastine 2 mg b.d. p.o. for 10 days on grass pollen-induced nasal responses in 16 patients with grass pollen allergic rhinitis has been assessed. The study was a double blind, randomized, placebo controlled, crossover trial, with a 10-14 day wash-out period. Patients were challenged with grass pollen before and after placebo and azelastine. The response was assessed by measurement of nasal resistance using active posterior rhinomanometry, by weighing nasal secretions, and by counting sneezes. The sensation of nasal obstruction was assessed with a visual analogue scale. After measurement of baseline total nasal resistance, doubling doses of allergen were sprayed into both nostrils at 15 min intervals until the nasal resistance was doubled. Cumulative doses of allergen that doubled prechallenge nasal resistance, numbers of sneezes and the amounts of nasal secretions were similar before azelastine as well as before and after placebo (cumulative dose, mean, (microgram): 2.3, 4.2 and 2.1 respectively, N.S.). After azelastine, the cumulative dose of allergen was increased (7.3 micrograms), and nasal secretions and the number of sneezes were decreased. The visual analogue scores were similar before and after azelastine as well as before and after the placebo. It is concluded that azelastine reduced the allergen-induced nasal responses.

To investigate possible differences in dendritic cells (DC) within intestinal tissue of mice before and after induction of colitis.Mucosal DC derived from intestinal tissue, as well as from mesenteric lymph nodes and spleen, were analyzed by fluorescence activated cell sorting (FACS) analysis. Supernatants of these cells were analyzed for secretion of different pro- and anti-inflammatory cytokines. Immunohistochemistry and immunofluorescence were performed on cryosections of mucosal tissue derived from animals with colitis as well as from healthy mice.It was shown that DC derived from healthy intestinal lamina propria (LP) represented an immature phenotype as characterized by low-level expression of costimulatory cytokines. In contrast to DC from spleen and mesenteric lymph nodes (MLN) that secreted proinflammatory cytokines, LP-DC produced high levels of the anti-inflammatory cytokine IL-10. After induction of murine colitis in a CD4(+)CD62L(+) transfer model or in chronic dextran sulfate sodium-colitis, a marked increase of activated CD80(+) DC could be observed within the inflamed colonic tissue. Interestingly, in contrast to splenic DC, a significant population of DC within MLN and colonic LP expressed the mucosal integrin CD103 which was lost during colitis.The constitutive secretion of anti-inflammatory cytokines by immature DC within the intestinal LP might regulate the homeostatic balance between mucosal immunity and tolerance. CD103(+) DC could mediate this important function.

In this study we will report on the first application of gas foil rotation in low pressure systems for growth of InP and GaAs based materials. Commercial reactors could be retrofitted with compatible designed susceptors allowing single rotation and planetary motion. The growth of GaAs/AlGaAs structures has been studied in the horizontal large scale low pressure reactor (5×2 inch wafer) using planetary motion of the wafers. Wafer-to-wafer uniformity of AlGaAs layer thickness of about 1% and compositional uniformity better than 0.4% have been achieved. InP and GaInAsP (λ=1.3 μm) have been grown under the same conditions yielding optimum material on the static susceptor. The thickness variation of these materials was less than 1.5%. The same numbers were found for dopant incorporation (SiH 4 ) at an average concentration of 10 16 cm -3 . Variation of lattice mismatch of GaInAs layers was less than 2×10 -4 over the wafer area. Photoluminescence wavelenght variation of quaternary layers of less than 3 nm could be obtained.