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First Results (first + result)
Selected AbstractsMorbidity and Health-Care Use in People with Intellectual Disabilities in General Practice: First Results of a Survey in the NetherlandsJOURNAL OF POLICY AND PRACTICE IN INTELLECTUAL DISABILITIES, Issue 2 2004H. M. J Van Schrojenstein Lantman-de Valk Abstract, Reported here are the preliminary results of the second Dutch National Survey of General Practice in which data were collected on all contacts with general practitioners (GPs) during a 12-month period to determine characteristics of patients with intellectual disabilities (ID). Sociodemographic characteristics differed significantly between people with ID and controls, indicating significant differences in morbidity between the two groups (people with ID were found to have more psychological problems, more digestive problems, more ear problems, more neurological problems, and more general and unspecified problems). [source] The Aachen Miniaturized Heart-Lung Machine,First Results in a Small Animal ModelARTIFICIAL ORGANS, Issue 11 2009Heike Schnoering Abstract Congenital heart surgery most often incorporates extracorporeal circulation. Due to foreign surface contact and the administration of foreign blood in many children, inflammatory response and hemolysis are important matters of debate. This is particularly an issue in premature and low birth-weight newborns. Taking these considerations into account, the Aachen miniaturized heart-lung machine (MiniHLM) with a total static priming volume of 102 mL (including tubing) was developed and tested in a small animal model. Fourteen female Chinchilla Bastard rabbits were operated on using two different kinds of circuits. In eight animals, a conventional HLM with Dideco Kids oxygenator and Stöckert roller pump (Sorin group, Milan, Italy) was used, and the Aachen MiniHLM was employed in six animals. Outcome parameters were hemolysis and blood gas analysis including lactate. The rabbits were anesthetized, and a standard median sternotomy was performed. The ascending aorta and the right atrium were cannulated. After initiating cardiopulmonary bypass, the aorta was cross-clamped, and cardiac arrest was induced by blood cardioplegia. Blood samples for hemolysis and blood gas analysis were drawn before, during, and after cardiopulmonary bypass. After 1 h aortic clamp time, all animals were weaned from cardiopulmonary bypass. Blood gas analysis revealed adequate oxygenation and perfusion during cardiopulmonary bypass, irrespective of the employed perfusion system. The use of the Aachen MiniHLM resulted in a statistically significant reduced decrease in fibrinogen during cardiopulmonary bypass. A trend revealing a reduced increase in free hemoglobin during bypass in the MiniHLM group could also be observed. This newly developed Aachen MiniHLM with low priming volume, reduced hemolysis, and excellent gas transfer (O2 and CO2) may reduce circuit-induced complications during heart surgery in neonates. [source] S23.1: Personality, Cancer and Coronary Heart Disease: First Results from the Heidelberg Longitudinal StudyBIOMETRICAL JOURNAL, Issue S1 2004Manfred Amelang No abstract is available for this article. [source] P1.18: Population-based Study of lymphomas in Germany: Rationale, Study design and First ResultsBIOMETRICAL JOURNAL, Issue S1 2004Alexandra Nieters No abstract is available for this article. [source] Phosphinites Derived from the 7-Phosphanorbornene Skeleton: First Results in Asymmetric Catalysis.CHEMINFORM, Issue 51 2003Magali Clochard Abstract For Abstract see ChemInform Abstract in Full Text. [source] Automatic Creation of Object Hierarchies for Radiosity ClusteringCOMPUTER GRAPHICS FORUM, Issue 4 2000Gordon Müller Using object clusters for hierarchical radiosity greatly improves the efficiency and thus usability of radiosity computations. By eliminating the quadratic starting phase very large scenes containing about 100k polygons can be handled efficiently. Although the main algorithm extends rather easily to using object clusters, the creation of ,good' object hierarchies is a difficult task both in terms of construction time and in the way how surfaces or objects are grouped to clusters. The quality of an object hierarchy for clustering depends on its ability to accurately simulate the hierarchy of the energy flow in a given scene. Additionally it should support visibility computations by providing efficient ray acceleration techniques. In this paper we will present a new approach of building hierarchies of object clusters. Our hybrid structuring algorithm provides accuracy and speed by combining a highly optimized bounding volume hierarchy together with uniform spatial subdivisions for nodes with regular object densities. The algorithm works without user intervention and is well suited for a wide variety of scenes. First results of using these hierarchies in a radiosity clustering environment are very promising and will be presented here. The combination of very deep hierarchies (we use a binary tree) together with an efficient ray acceleration structure shifts the computational effort away from form factor and visibility calculation towards accurately propagating the energy through the hierarchy. We will show how an efficient single pass gathering can be used to minimize traversal costs. [source] Versatility of Laser Pyrolysis Applied to the Synthesis of TiO2 Nanoparticles , Application to UV AttenuationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2008Bruno Pignon Abstract TiO2 nanoparticles show interesting catalytic and optical properties and are therefore highly demanded for several applications. In this paper, we show that pure and N-doped TiO2 powders with an average diameter as low as 8 nm can be synthesized by laser pyrolysis, with the use of an aerosol of TTIP (titanium tetraisopropoxide) as the main precursor sensitized by C2H4. We demonstrate the possibility to control the anatase/rutile phase ratio over a large range, which was not achieved before, by tuning the experimental parameters. N-doped particles have also been produced for the first time by this method by using a one-step process through addition of NH3. First results illustrating the consequences in terms of UV absorption properties are also presented and correlated with the structural evolution and the presence of a doping element.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Valuation of health states in the US study to establish disability weights: lessons from the literatureINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 1 2010Jürgen Rehm Abstract The metric of disability-adjusted life years (DALYs) has become the global standard of measuring burden of disease. DALYs are comprised of years of life lost due to premature mortality and years of healthy life lost due to living with disability. In order to calculate the second part of the DALY equation, disease specific disability weights have to be established, i.e. measures for the decline of health associated with these disease states, which vary between zero for perfect health and one for death. Although these disability weights are key for estimating DALYs, there have not been many comprehensive studies with empirical determinations of them. This article describes a systematic review on the state of the art with respect to empirically determining disability weights. Based on this review, a multi-method approach is outlined, which has also been implemented in a US study to measure burden of disease. This approach involves the use of psychometric methodology as well as economic trade-off methods for determining the value of health states. It is conceptualized as a disaggregated approach, where the disability weight of any health state can be calculated if the attributes of this health state are known. The US study received the collaboration of experts from more than 20 institutes of the National Institutes of Health and of the Centers for Disease Control and Prevention. First results will be available by the end of this year. Copyright © 2010 John Wiley & Sons, Ltd. [source] First results from the Canadian SGM beamline at SRCJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2000B. W. Yates The first experimental results obtained from the Canadian SGM beamline at SRC (Synchrotron Radiation Centre, University of Wisconsin-Madison, USA) are reported. The beamline is based on the Dragon-type design, with a constant deviation angle, using photons from a second-generation bending-magnet light source. The medium-energy grating on this beamline covers a photon energy range from 240 to 700,eV, with a ruling density of 600,lines,mm,1. A maximum resolving power of ,10000 is achieved at a photon energy of ,400,eV. Gas-phase absorption spectra collected at the N, O and C K -edges are presented to demonstrate the excellent performance of this beamline. High-resolution absorption spectra of some C- and Ti-containing solid-state samples are also reported. [source] Early administration of surfactant in spontaneous breathing with nCPAP: feasibility and outcome in extremely premature infants (postmenstrual age ,27 weeks)PEDIATRIC ANESTHESIA, Issue 4 2007ANGELA KRIBS MD Summary Background:, Spontaneous breathing supported by nasal continuous positive airway pressure (nCPAP) is thought to have some advantages compared with mechanical ventilation in extremely premature infants. In addition, early or prophylactic surfactant administration has been shown to be superior to delayed use. A strategy to combine these two principles was tested in our neonatal intensive care unit (NICU). The aim of this feasibility study was to describe the procedure and compare short-term results with a historical control. Methods:, The study took place in a level III NICU. In the observational period all extremely premature infants with clinical signs of moderate to severe respiratory distress syndrome despite nCPAP received 100 mg·kg,1 of a natural surfactant preparation via an intratracheal catheter during spontaneous breathing. In the historical control period those infants were intubated and ventilated to receive surfactant. Results:, Twenty-nine of 42 infants fulfilled the criteria and were treated with the new approach. In five cases ventilation with manual bag was necessary after administration of surfactant but all infants could be retransferred to nCPAP within a few minutes. Ten infants were intubated later during the first 3 days. Mortality was 7% in the group of infants treated in this way and 12% in all infants treated during the observational period. Mortality was 35% in the historical control period. Morbidity was within ranges reported by other authors. Conclusions:, Surfactant administration during nCPAP is feasible. First results indicate that early complications are rare. This warrants a prospective randomized trial. [source] AlGaN epitaxial layers grown by HVPE on sapphire substratesPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 6 2006V. Soukhoveev Abstract Growth of AlxGa1,xN (x , 0.0-1.0) alloy layers by hydride vapor pahse epitaxy (HVPE) is reported. Crack-free undoped AlGaN layers from 0.1 to 2 ,m thick were grown on 2, SiC and 2,and 4, sapphire substrates. For AlxGa1,xN (x , 0.7-0.8) layers grown on sapphire, high-resolution symmetric/asymmetric X-ray diffraction (XRD) measurements resulted in ,-scan rocking curve widths ranging from 250 to 650 arcsec and from 1400 to 1900 arcsec, for the (00.2) and (10.2) reflections, respectively. Minimum XRD-estimated screw and edge dislocation densities in AlGaN layers grown on sapphire were <6 x 108 cm,2 and <2 x 109 cm,2, respectively. Raman studies revealed that the composition dependences of the phonon modes of HVPE-grown AlxGa1,xN layers are in a good agreement with the one, which have been observed for MOCVD-grown AlxGa1,xN alloys earlier. Grown layers had n-type electrical conductivity for the composition range up to x = 0.4. The layer became highly resistive for higher AlN contents. First results on 40 µm thick crack free AlGaN growth on SiC substrates are reported. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] First results of a quantitative study of DNA adducts of melphalan in the rat by isotope dilution mass spectrometry using capillary liquid chromatography coupled to electrospray tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 14 2005Bart Van den Driessche Rats were intravenously injected with a single high dose (10,mg/kg) of the alkylating agent melphalan in order to study DNA-adduct formation. Quantitation of a dGuo-melphalan adduct was done by isotope dilution mass spectrometry using capillary liquid chromatography/mass spectrometry (LC/MS) and [15N5]-labeled dGuo-melphalan as internal standard. DNA-adduct levels were studied in bone marrow, liver and kidney. The instrumental detection limit of the method was determined to be 900,fg (S/N 3, pure standard). These first results clearly show a 10 times higher adduct level in bone marrow compared to kidney and a 6 times higher level compared to liver. More experiments will be necessary to gather more information on the pharmacokinetics of melphalan-DNA adducts under in vivo conditions. Copyright © 2005 John Wiley & Sons, Ltd. [source] Osteobiographic analysis of skeleton I, Sítio Toca dos Coqueiros, Serra da Capivara National Park, Brazil, 11,060 BP: First resultsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2002Andrea Lessa Abstract This paper presents an osteobiographic analysis of a single skeleton found in a small rock shelter known as Toca dos Coqueiros, Piauí, Brazil. This find is of interest because of an exceptionally old radiocarbon date associated with it. The date (11,060 BP) was obtained from charcoal associated directly with the skeleton. This is an interesting find because of the rarity of osteobiographic studies of skeletons of such antiquity. Despite the existence of two projectile points in association with the burial, the morphological and molecular analyses of the skeleton demonstrated that this was a female. She was about 35,45 years of age at death. The skeleton exhibited acute and chronic bone lesions. Oral pathology was also observed, including an interproximal dental groove, probably caused by the therapeutic use of a cactus thorn. This could be one of the oldest cases of an analgesic plant used in the prehistoric Americas. Am J Phys Anthropol 118:99,110, 2002. © 2002 Wiley-Liss, Inc. [source] Advances of pulsed laser deposition of ZnO thin filmsANNALEN DER PHYSIK, Issue 1-2 2004M. Lorenz Abstract Advances in Pulsed Laser Deposition (PLD) equipment and process design for the epitaxy of ZnO thin films on a-, and c-oriented sapphire substrates are reported. The achieved improvement of device relevant ZnO layer properties is directly related to our equipment design and novel process schemes. First results on growth and reflectivity of ZnO-MgO based dielectric Bragg resonators for future ZnO-based light emitter devices are shown. [source] First results on a relation between ovarian fluid and egg proteins of Salmo trutta and egg qualityAQUACULTURE RESEARCH, Issue 2 2007Franz Lahnsteiner Abstract By use of sodium dodecyl sulfate polyacrylamide gel electrophoresis, ovarian fluid proteins and main proteins of unfertilized eggs were qualitatively and quantitatively investigated in the brown trout, Salmo trutta, to see whether some of them were correlated with the rate of embryos reaching the eyed embryo stage. In the ovarian fluid, 12 types of proteins in the range of 39,166 kDa were detected whereby three proteins were lipoproteins and two were glycoproteins. Ovarian fluid proteins with a molecular weight of 85, 68, 62 and 39 kDa were negatively correlated with the percentage of eyed stage embryos. The statistical significance of the relations was low in simple and multiple regression models (R2,0.534) indicating that the relations were influenced and superposed by other factors. Therefore, ovarian fluid proteins give only poor information about maturity and quality of eggs. In the eggs, nine major types of proteins in the range of 95,15 kDa were identified. The 95 kDa protein was a lipoprotein, the 85 and the 62 kDa protein were glycoproteins, and the 15 kDa protein was a phosphoprotein. The 95, 85, 77 and 39 kDa protein were positively correlated with embryo survival to the eyed embryo stage. The explanatory effect of the multiple regression model was very high (R2=0.961) indicating that distinct egg proteins are closely related with egg quality. [source] Satellite radar observation of tropical peat swamp forest as a tool for hydrological modelling and environmental protectionAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2007Dirk H. Hoekman Abstract 1.Tropical peat swamp forests may contain as much as 20% of the global soil carbon stock. They are threatened by large-scale deforestation and canal drainage. Oxidation and forest fire cause enormous carbon emissions. Most remaining areas are located in Indonesia. These are becoming increasingly important for maintaining biodiversity. 2.Time series of historical JERS-1 SAR data reveal the extent and nature of recent disturbances, such as those caused by excess drainage and severe ENSO events. Examples are given for a number of peat swamp forest areas in Sumatra and Borneo. 3.Peat swamp hydrology is studied along a 23-km transect, which crosses a complete peat dome. First results show the relevance of surface runoff and peat soil roughness in the description of flooding events, and have been used to produce an improved hydrological description. 4.Since the dynamics of flooding events can potentially be observed by the ALOS PALSAR instrument (yet to be launched), this new hydrological model can be used to infer parameters relevant for detection of ecosystem disturbance and evaluation of restoration efforts. Copyright © 2007 John Wiley & Sons, Ltd. [source] The role of emerging bipoles in the formation of a sunspot penumbraASTRONOMISCHE NACHRICHTEN, Issue 6 2010R. Schlichenmaier Abstract The generation of magnetic flux in the solar interior and its transport from the convection zone into the photosphere, the chromosphere, and the corona will be in the focus of solar physics research for the next decades. With 4 m class telescopes, one plans to measure essential processes of radiative magneto-hydrodynamics that are needed to understand the nature of solar magnetic fields. One key-ingredient to understand the behavior of solar magnetic field is the process of flux emergence into the solar photosphere, and how the magnetic flux reorganizes to form the magnetic phenomena of active regions like sunspots and pores. Here, we present a spectropolarimetric and imaging data set from a region of emerging magnetic flux, in which a proto-spot without penumbra forms a penumbra. During the formation of the penumbra the area and the magnetic flux of the spot increases. First results of our data analysis demonstrate that the additional magnetic flux, which contributes to the increasing area of the penumbra, is supplied by the region of emerging magnetic flux. We observe emerging bipoles that are aligned such that the spot polarity is closer to the spot. As an emerging bipole separates, the pole of the spot polarity migrates towards the spot, and finally merges with it. We speculate that this is a fundamental process, which makes the sunspot accumulate magnetic flux. As more and more flux is accumulated a penumbra forms and transforms the proto-spot into a full-fledged sunspot (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The NST: First results and some lessons for ATST and ESTASTRONOMISCHE NACHRICHTEN, Issue 6 2010P.R. Goode Abstract In January 2009, first light observations with the NST (New Solar Telescope) in Big Bear Solar Observatory (BBSO) were made. NST has a 1.7 m primary with a 1.6 m clear aperture. First observational results in TiO and H, are shown and discussed. The NST primary mirror is the most aspheric telescope mirror deployed to date. The NST is early in its commissioning, and the plans for this phase will be sketched. Lessons learned in building and implementing the NST are germane for the ATST and EST telescopes and will be discussed. The NST has an off-axis Gregorian configuration consisting of a parabolic primary, heat-stop, elliptical secondary and diagonal flats. The focal ratio of the primary mirror is f/2.4. The working wavelength range covers from 0.4 to 1.7 µm in the Coudé Lab beneath the telescope and all wavelengths including the far infrared at the Nasmyth focus on the dome floor (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] First results from SPIFFI.ASTRONOMISCHE NACHRICHTEN, Issue 2 2004I: The Galactic Center Abstract In this and a companion paper (Eisenhauer et al. 2003b), we discuss some of the scientific results obtained during the SPIFFI guest instrument runs at the VLT in March and April 2003. This paper concentrates on results for the Galactic Center. Section 1 discusses the stellar population of the Galactic Center, in which we clearly detect, for the first time, an early, hot WN star, as well as a large number of WC stars. Analysis of the stellar population indicates that the young stars in the Galactic Center originated in a high metalicity starburst about 5 Myr ago. A surprising result is that essentially all young stars in the central 10, belong to one of two well defined, rotating stellar rings/disks. Section 2 outlines a new determination of the distance to the Galactic Center which is essentially free of systematic uncertainties in the astrophysical modelling, and gives Ro as 7.94 ± 0.42 kpc. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Understanding African easterly waves: a moist singular vector approachATMOSPHERIC SCIENCE LETTERS, Issue 3 2009Rosalind J. Cornforth Abstract Moist singular vectors (MSV) have been applied successfully to predicting mid-latitude storms growing in association with latent heat of condensation. Tropical cyclone sensitivity has also been assessed. Extending this approach to more general tropical weather systems here, MSVs are evaluated for understanding and predicting African easterly waves, given the importance of moist processes in their development. First results, without initial moisture perturbations, suggest MSVs may be used advantageously. Perturbations bear similar structural and energy profiles to previous idealised non-linear studies and observations. Strong sensitivities prevail in the metrics and trajectories chosen, and benefits of initial moisture perturbations should be appraised. Copyright © 2009 Royal Meteorological Society [source] Das Magnitude 8.8 Maule (Chile)-Erdbeben vom 27.BAUTECHNIK, Issue 10 2010Februar 2010, Ingenieuranalyse der Tsunamischäden, Teil Das Maule (Chile)-Erdbeben vom 27. Februar 2010 gehört zu den stärksten, weltweit jemals registrierten Erdbeben. Das seismische Ereignis löste einen Tsunami aus, der durch mehrere Wellenfronten verheerende Schäden an der Küste Chiles verursachte. Ereignisspezifische Besonderheiten aus der überlagerung der Effekte aus Erdbeben und darauffolgenden Flutwellen (Tsunami) waren Motivation, im Rahmen einer Erkundungsmission der Ingenieurgruppe der Deutschen Task Force im betroffenen Gebiet die Bauwerksschäden aufzunehmen und ihre regionale Verteilung zu dokumentieren. Der Beitrag vermittelt einen Eindruck von den durch den Tsunami bedingten Schäden; es wird der Versuch unternommen, das Verhalten der typischen Bauweisen unter den zeitlich sequentiell auftretenden extremen Einwirkungen aufzuzeigen. Die Auswertungen schließen an die Ingenieuranalyse der Erdbebenschäden an, so dass auf die im vorangegangenen 1. Teil des Beitrags vom August 2010 [1] gegebene allgemeine übersicht zum Gebäudebestand in Chile und zur Typisierung der Bauweisen verwiesen werden kann. Die Schäden aus dem Tsunami konzentrieren sich auf die eher ländlichen und ohnehin weniger tauglichen traditionellen Bauweisen in den Küstenregionen. An den wesentlichen Wirkungsmechanismen eines Tsunami werden die Verletzbarkeit der Bauweisen und die Effizienz einfacher baulicher Schutzmaßnahmen herausgearbeitet. Wie gezeigt werden kann, tragen Schäden aus Treibgut erheblich zum Schadensbild bei. The Magnitude 8.8 Maule (Chile) earthquake of February 27, 2010 , Engineering analysis of tsunami damages. The Maule (Chile) February 27, 2010 earthquake is regarded as one of the strongest earthquakes ever recorded world-wide. The seismic event triggered a tsunami which caused by several wave fronts serious damage alongside the coastal border. Event-specific characteristics from the overlay of the effects from earthquakes and following flood wave (Tsunami) were motivation to examine building damage and to document their regional distribution, in the context of a reconnaissance mission of the engineering group of the German Task Force for earthquakes. The paper provides an impression from the tsunami induced damage to the different building types under the impact of time-varying sequence of extreme natural events. First results of the studies in [1] are related to the engineering analysis of earthquake damage. Therefore it can be referred to the overview of the building stock and the predominant structural systems in Chile given there. Damage caused by the tsunami is concentrated on rural and often less resistant traditional buildings in coastal areas. The main loading and impact components induced by the tsunami are used to explain the vulnerability of building types and the efficiency of simple structural measures. As the damage cases demonstrate, debris in its general sense has contributed to the observed effects. [source] Sequence-specific Methyltransferase- Induced Labeling of DNA (SMILing DNA)CHEMBIOCHEM, Issue 3 2004Goran Pljevalj Abstract A new concept for sequence-specific labeling of DNA by using chemically modified cofactors for DNA methyltransferases is presented. Replacement of the amino acid side chain of the natural cofactor S -adenosyl- L -methionine with an aziridine group leads to a cofactor suitable for DNA methyltransferase-catalyzed sequence-specific coupling with DNA. Sequence-specifically fluorescently labeled plasmid DNA was obtained by using the DNA methyltransferase from Thermus aquaticus (M.TaqI) as catalyst and attaching a fluorophore to the aziridine cofactor. First results suggest that all classes of DNA methyltransferases with different recognition sequences can be used. In addition, this novel method for DNA labeling should be applicable to a wide variety of reporter groups. [source] Broadband dielectric spectroscopy on the molecular dynamics in different generations of hyperbranched polyesterJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2009Gamal Turky Abstract Dielectric spectroscopy (10,2 Hz to 106 Hz) was employed to investigate the molecular dynamics of hyperbranched polyesters where the number of the generation is systematically varied from 2 to 5. As a first result, the dielectric properties depends strongly on the generation of the hyperbranched polymers. For higher generations (3 to 5) at temperatures below Tg two relaxation processes are observed, a ,-process at lower temperatures and a ,-process at higher ones. The apparent activation energies are around 100 kJ/mol which seems to be too high for truly localized processes. For the Generation 2, only the ,-process is observed. For all investigated polymers the dielectric ,-relaxation could not be observed because of strong conductivity effects. Therefore, the conductivity is systematically analyzed which obeys the peculiarities found to be characteristic for semiconducting disordered materials. Especially, the Barton/Nakajima/Namikawa relationship is found to be valid. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source] On a class of holomorphic functions representable by Carleman formulas in the disk from their values on the arc of the circleMATHEMATISCHE NACHRICHTEN, Issue 1-2 2007Lev Aizenberg Abstract Let D be a unit disk andM be an open arc of the unit circle whose Lebesgue measure satisfies 0 < l (M) < 2,. Our first result characterizes the restriction of the holomorphic functions f , ,(D), which are in the Hardy class ,1 near the arcM and are denoted by ,, ,1M(,,), to the open arcM. This result is a direct consequence of the complete description of the space of holomorphic functions in the unit disk which are represented by the Carleman formulas on the open arc M. As an application of the above characterization, we present an extension theorem for a function f , L1(M) from any symmetric sub-arc L , M of the unit circle, such that , M, to a function f , ,, ,1L(,,). (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Platinum group elements provide no indication of a meteoritic component in ICDP cores from the Bosumtwi crater, GhanaMETEORITICS & PLANETARY SCIENCE, Issue 4-5 2007S. GODERIS The majority of the samples come from the impactite material recovered by cores LB-07A and LB-08A, which were drilled by the International Continental Scientific Drilling program (ICDP). One sample originates from the fallback material found at the contact between the impactite and the overlying lake sediment in core LB-05B. No clear signature of a meteoritic contamination was identified in the 13 impactite samples. The target rock apparently dominates the PGE contribution in the impactites. These results agree with the PGE concentrations reported for the suevites collected at the crater rim and in other parts of the Bosumtwi ICDP cores. However, based on Cr and Os isotopic signatures, a meteoritic component could be present in the sample of fallback material, supporting the reports of the existence of meteoritic material in the Ivory Coast tektites. Further analyses of the fallback material from the Bosumtwi drill cores should confirm (or not) this first result. [source] On a wave map equation arising in general relativityCOMMUNICATIONS ON PURE & APPLIED MATHEMATICS, Issue 5 2004Hans Ringström We consider a class of space-times for which the essential part of Einstein's equations can be written as a wave map equation. The domain is not the standard one, but the target is hyperbolic space. One ends up with a 1 + 1 nonlinear wave equation, where the space variable belongs to the circle and the time variable belongs to the positive real numbers. The main objective of this paper is to analyze the asymptotics of solutions to these equations as t , ,. For each point in time, the solution defines a loop in hyperbolic space, and the first result is that the length of this loop tends to 0 as t,1/2 as t , ,. In other words, the solution in some sense becomes spatially homogeneous. However, the asymptotic behavior need not be similar to that of spatially homogeneous solutions to the equations. The orbits of such solutions are either a point or a geodesic in the hyperbolic plane. In the nonhomogeneous case, one gets the following asymptotic behavior in the upper half-plane (after applying an isometry of hyperbolic space if necessary): 1The solution converges to a point. 2The solution converges to the origin on the boundary along a straight line (which need not be perpendicular to the boundary). 3The solution goes to infinity along a curve y = const. 4The solution oscillates around a circle inside the upper half-plane. Thus, even though the solutions become spatially homogeneous in the sense that the spatial variations die out, the asymptotic behavior may be radically different from anything observed for spatially homogeneous solutions of the equations. This analysis can then be applied to draw conclusions concerning the associated class of space-times. For instance, one obtains the leading-order behavior of the functions appearing in the metric, and one can conclude future causal geodesic completeness. © 2004 Wiley Periodicals, Inc. [source] Ion-Conducting Probes for Low Temperature PlasmasCONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-7 2008S. A. Meiss Abstract Probes interacting with a low temperature plasma are typically built of electron conducting materials, mostly metals. We apply yttria-stabilized zirconia (YSZ) which is oxygen ion conducting at elevated temperatures and which is a typical solid electrolyte with high ionic and negligible electronic conductivity. The processes at the plasma|YSZ interface are discussed and first results of measurements with ion-conducting single- and double-probes in oxygen containing radio frequency plasmas are presented. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Single cell manipulation, analytics, and label-free protein detection in microfluidic devices for systems nanobiologyELECTROPHORESIS, Issue 19 2005Wibke Hellmich Abstract Single cell analytics for proteomic analysis is considered a key method in the framework of systems nanobiology which allows a novel proteomics without being subjected to ensemble-averaging, cell-cycle, or cell-population effects. We are currently developing a single cell analytical method for protein fingerprinting combining a structured microfluidic device with latest optical laser technology for single cell manipulation (trapping and steering), free-solution electrophoretical protein separation, and (label-free) protein detection. In this paper we report on first results of this novel analytical device focusing on three main issues. First, single biological cells were trapped, injected, steered, and deposited by means of optical tweezers in a poly(dimethylsiloxane) microfluidic device and consecutively lysed with SDS at a predefined position. Second, separation and detection of fluorescent dyes, amino acids, and proteins were achieved with LIF detection in the visible (VIS) (488,nm) as well as in the deep UV (266,nm) spectral range for label-free, native protein detection. Minute concentrations of 100,fM injected fluorescein could be detected in the VIS and a first protein separation and label-free detection could be achieved in the UV spectral range. Third, first analytical experiments with single Sf9 insect cells (Spodoptera frugiperda) in a tailored microfluidic device exhibiting distinct electropherograms of a green fluorescent protein-construct proved the validity of the concept. Thus, the presented microfluidic concept allows novel and fascinating single cell experiments for systems nanobiology in the future. [source] In Vivo Modulation of Hippocampal Epileptiform Activity with Radial Electric FieldsEPILEPSIA, Issue 6 2003Kristen A. Richardson Summary: Purpose: Electric field stimulation can interact with brain activity in a subthreshold manner. Electric fields have been previously adaptively applied to control seizures in vitro. We report the first results from establishing suitable electrode geometries and trajectories, as well as stimulation and recording electronics, to apply this technology in vivo. Methods: Electric field stimulation was performed in a rat kainic acid injection seizure model. Radial electric fields were generated unilaterally in hippocampus from an axial depth electrode. Both sinusoidal and multiphasic stimuli were applied. Hippocampal activity was recorded bilaterally from tungsten microelectrode pairs. Histologic examination was performed to establish electrode trajectory and characterize lesioning. Results: Electric field modulation of epileptiform neural activity in phase with the stimulus was observed in five of six sinusoidal and six of six multiphasic waveform experiments. Both excitatory and suppressive modulation were observed in the two experiments with stimulation electrodes most centrally placed within the hippocampus. Distinctive modulation was observed in the period preceding seizure-onset detection in two of six experiments. Short-term histologic tissue damage was observed in one of six experiments associated with high unbalanced charge delivery. Conclusions: We demonstrated in vivo electric field modulation of epileptiform hippocampal activity, suggesting that electric field control of in vivo seizures may be technically feasible. The response to stimulation before seizure could be useful for triggering control systems, and may be a novel approach to define a preseizure state. [source] A New Technique for Severe Plastic Deformation: The Cone,Cone MethodADVANCED ENGINEERING MATERIALS, Issue 12 2009Olivier Bouaziz Abstract A new technique for producing ultrafine grained materials by severe plastic deformation is proposed. The principle and possible design of this technique, referred to as "cone,cone method," are outlined and the first results of numerical simulations that demonstrate its feasibility are reported. These results give promise with regard to achieving very large plastic strains and the concomitant grain refinement in sheet products. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||