Optimization and design of three-dimensional aerodynamic configurations of arbitrary shape by a vortex lattice method

A new method based on vortex lattice theory has been developed which can be applied to the combined analysis, induced drag optimization, and aerodynamic design of three-dimensional configurations of arbitrary shape. Geometric and aerodynamic constraints can be imposed on both the optimization and the design process. The method is compared with several known analytical solutions and is applied to several different design and optimization problems, including formation flight and wingtip fins for the Boeing KC-135 tanker airplane. Good agreement has been observed between the theoretical predictions and the wind tunnel test results for the KC-135 modification

Demografischer Wandel - Japans Strategien

Der demografische Wandel beschleunigt sich allmählich. Als eine der wichtigsten gesellschaftlichen Entwicklungen unseres Jahrhunderts charakterisieren ihn zunehmend deutliche Verschiebungen in vielen Bevölkerungsstrukturen. Dies stellt immer mehr Länder vor eine Reihe unterschiedlicher Herausforderungen. Nicht nur wirkungsstarke sozialpolitische Konsequenzen können mittlerweile abgesehen werden. Viele Fakten sprechen dafür, dass der demografische Wandel auch einen tief liegenden makroökonomischen Strukturwandel hervorrufen wird. In Japan ist die Veränderung durch den demografischen Wandel besonders fortgeschritten und intensiv. Sie ist in weiten Teilen zudem charakteristisch für die Umwälzungen, die auf viele andere Industriestaaten in absehbarer Zeit zukommen werden. In der vorliegenden Arbeit wird mit dem Ansatz der wissenschaftlichen Zukunftsforschung ein Bogen von der internationalen Dimension des demografischen Wandels über die extremen Ausprägungen in Japan bis hin zu einzelnen Strategien der japanischen Regierung gespannt. Es wird aufgezeigt, warum das Zusammenspiel der drei demografischen Variablen Geburtenrate, Lebenserwartung und Migration in Japan zu einem Ungleichgewicht führt, und befunden, dass die verfolgten strategischen Ansätze um dieses Ungleichgewicht auszugleichen bisher noch deutlich zu kurz greifen

The brattleboro rat displays a natural deficit in social discrimination that is restored by clozapine and a neurotensin analog.

Cognitive deficits in schizophrenia are a major source of dysfunction for which more effective treatments are needed. The vasopressin-deficient Brattleboro (BRAT) rat has been shown to have several natural schizophrenia-like deficits, including impairments in prepulse inhibition and memory. We investigated BRAT rats and their parental strain, Long-Evans (LE) rats, in a social discrimination paradigm, which is an ethologically relevant animal test of cognitive deficits of schizophrenia based upon the natural preference of animals to investigate conspecifics. We also investigated the effects of the atypical antipsychotic, clozapine, and the putative antipsychotic, PD149163, a brain-penetrating neurotensin-1 agonist, on social discrimination in these rats. Adult rats were administered saline or one of the three doses of clozapine (0.1, 1.0, or 10 mg/kg) or PD149163 (0.1, 0.3, or 1.0 mg/kg), subcutaneously. Following drug administration, adult rats were exposed to a juvenile rat for a 4-min learning period. Animals were then housed individually for 30 min and then simultaneously exposed to the juvenile presented previously and a new juvenile for 4 min. Saline-treated LE rats, but not BRAT rats, exhibited intact social discrimination as evidenced by greater time spent exploring the new juvenile. The highest dose of clozapine and the two highest doses of PD149163 restored social discrimination in BRAT rats. These results provide further support for the utility of the BRAT rat as a genetic animal model relevant to schizophrenia and drug discovery. The potential of neurotensin agonists as putative treatments for cognitive deficits of schizophrenia was also supported

Silica nanoparticles for the layer-by-layer assembly of fully electro-active cytochrome c multilayers

<p>Abstract</p> <p>Background</p> <p>For bioanalytical systems sensitivity and biomolecule activity are critical issues. The immobilization of proteins into multilayer systems by the layer-by-layer deposition has become one of the favorite methods with this respect. Moreover, the combination of nanoparticles with biomolecules on electrodes is a matter of particular interest since several examples with high activities and direct electron transfer have been found. Our study describes the investigation on silica nanoparticles and the redox protein cytochrome <it>c </it>for the construction of electro-active multilayer architectures, and the electron transfer within such systems. The novelty of this work is the construction of such artificial architectures with a non-conducting building block. Furthermore a detailed study of the size influence of silica nanoparticles is performed with regard to formation and electrochemical behavior of these systems.</p> <p>Results</p> <p>We report on interprotein electron transfer (IET) reaction cascades of cytochrome <it>c </it>(cyt <it>c</it>) immobilized by the use of modified silica nanoparticles (SiNPs) to act as an artificial matrix. The layer-by-layer deposition technique has been used for the formation of silica particles/cytochrome <it>c </it>multilayer assemblies on electrodes. The silica particles are characterized by dynamic light scattering (DLS), Fourier transformed infrared spectroscopy (FT-IR), Zeta-potential and transmission electron microscopy (TEM). The modified particles have been studied with respect to act as an artificial network for cytochrome <it>c </it>and to allow efficient interprotein electron transfer reactions. We demonstrate that it is possible to form electro-active assemblies with these non-conducting particles. The electrochemical response is increasing linearly with the number of layers deposited, reaching a cyt <it>c </it>surface concentration of about 80 pmol/cm²with a 5 layer architecture. The interprotein electron transfer through the layer system and the influence of particle size are discussed.</p> <p>Conclusions</p> <p>This study demonstrates the ability to construct fully electro-active cyt <it>c </it>multilayer assemblies by using carboxy-modified silica nanoparticles. Thus it can be shown that functional, artificial systems can be build up following natural examples of protein arrangements. The absence of any conductive properties in the second building block clearly demonstrates that mechanisms for electron transfer through such protein multilayer assemblies is based on interprotein electron exchange, rather than on wiring of the protein to the electrode.</p> <p>The construction strategy of this multilayer system provides a new controllable route to immobilize proteins in multiple layers featuring direct electrochemistry without mediating shuttle molecules and controlling the electro-active amount by the number of deposition steps.</p

NEXAFS spectroscopy and site-specific fragmentation of N -methylformamide, N,N -dimethylformamide, and N,N -dimethylacetamide

Near-edge X-ray absorption fine-structure (NEXAFS) spectra measured at the C, N, and O K-edges for three molecules containing the amide moiety, N-methylformamide (HCONHCH3), N,Ndimethylformamide (HCON(CH3)2), and N,N-dimethylacetamide (CH3CON(CH3)2) are presented. These molecules have similar structures and differ by the number of methyl groups located at the molecular ends. The fragmentation of these molecules after resonant excitation at different K-edge resonances is also investigated, using a 3D-ion imaging time-of-flight spectrometer. A comparison between the molecules with respect to the relative contributions of the fragments created upon excitation at distinct resonances reveals site-specific fragmentation. Further information about the character of the core-excitation and dissociation process is obtained from the angular distributions of the ion fragments

Single photon thermal ionization of C60

We report on experiments which show that C60 can ionize in an indirect, quasi-thermal boiloff process after absorption of a single photon. The process involves a large number of incoherently excited valence electrons and yields electron spectra with a Boltzmann distribution with temperatures exceeding 10^4 K. It is expected to be present for other molecules and clusters with a comparatively large number of valence electrons. The astrophysical consequences are briefly discussed

Quantitative Determination of Natriuretic Peptides in Human Biological Samples with a Bioassay Using Cultured Cells

Peer Reviewe