9,445 research outputs found

    Sharp thresholds of blow-up and global existence for the coupled nonlinear Schrodinger system

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    In this paper, we establish two new types of invariant sets for the coupled nonlinear Schrodinger system on Rn\mathbb{R}^n, and derive two sharp thresholds of blow-up and global existence for its solution. Some analogous results for the nonlinear Schrodinger system posed on the hyperbolic space Hn\mathbb{H}^n and on the standard 2-sphere S2\mathbb{S}^2 are also presented. Our arguments and constructions are improvements of some previous works on this direction. At the end, we give some heuristic analysis about the strong instability of the solitary waves.Comment: 21 page

    Analyzing redshift surveys to measure the power spectrum on large scales

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    Upcoming large redshift surveys potentially allow precision measurements of the galaxy power spectrum. To accurately measure P(k) on the largest scales, comparable to the depth of the survey, it is crucial that finite volume effects are accurately corrected for in the data analysis. Here we derive analytic expressions for the one such effect that has not previously been worked out exactly: that of the so-called integral constraint. We also show that for data analysis methods based on counts in cells, multiple constraints can be included via simple matrix operations, thereby rendering the results less sensitive to galactic extinction and misestimates of the shape of the radial selection function.Comment: Mostly superseded by astro-ph/9708020; from 5/5-97. 10 pages, with 1 figure included. More detailed treatment at http://www.sns.ias.edu/~max/galpower.html (faster from the US), from http://www.mpa-garching.mpg.de/~max/galpower.html (faster from Europe) or from [email protected]

    Off-label use in germany - a current appraisal of gynaecologic university departments

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    <p>Abstract</p> <p>Objective</p> <p>The off-label use, referring to the applicability of pharmaceutical drugs beyond the submitted and from the Federal Institute for Drugs and Medical Devices (BfArM, Bundesamt für Arzneimittel und Medizinprodukte) certified and approved administration, is the subject of controversial discussions. the application can be considered in case of severe illness - if no therapeutic alternatives are available - or it exists as a founded perspective for achieving therapeutic success.</p> <p>Methods</p> <p>A latitudinal study for evaluating the application of off-label use supplements was performed at 43 German university and academic teaching hospitals. Five doctors at each hospital applied off-label pharmaceutical drugs and were called upon to share their personal experience to the application of those medications.</p> <p>Results</p> <p>75 (35%) questionnaires were returned out of 22 (51%) medical centres with 215 contacted physicians. Off-label use was common for 65 (91%) of the physicians. Only 9% of them obviate the application of off-label drugs. About a half of the medication is related to application in obstetrics (54%) and in most cases on an every day basis. Uterotonics were the most commonly used off-label medications (34%). The main part of information about off-label use is obtained from personal information of colleagues (66%) and personal experience (58%). 34% of physicians think that off label use is risky. Interestingly, the view about off label use of medication varies considerably among physicians from various hospitals.</p> <p>Conclusions</p> <p>The application of off-label pharmaceutical drugs in Germany seems to be a well established practice. More than 90% of participators of our trial use at least one medication outside the administration. This includes particularly prostaglandins, anti-hyper-tonic therapeutics and chemotherapeutics.</p

    Design-of-experiments-guided optimization of slurry-cast cathodes for solid-state batteries

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    Laboratory research into bulk-type solid-state batteries (SSBs) has been focused predominantly on powder-based, pelletized cells and has been sufficient to evaluate fundamental limitations and tailor the constituents to some degree. However, to improve experimental reliability and for commercial implementation of this technology, competitive slurry-cast electrodes are required. Here, we report on the application of an approach guided by design of experiments (DoE) to evaluate the influence of the type/content of polymer binder and conductive carbon additive on the cyclability and processability of Li1+x_{1+x}(Ni0.6_{0.6}Co0.2_{0.2}Mn0.2_{0.2})1_{1}−xO2_{2} (NCM622) cathodes in SSB cells using lithium thiophosphate solid electrolytes. The predictions are verified by charge-discharge and impedance spectroscopy measurements. Furthermore, structural changes and gas evolution are monitored via X-ray diffraction and differential electrochemical mass spectrometry, respectively, in an attempt to rationalize and support the DoE results. In summary, the optimized combination of polymer binder and conductive carbon additive leads to high electrochemical performance and good processability

    A comparison of the galaxy peculiar velocity field with the PSCz gravity field-- A Bayesian hyper-parameter method

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    We constructed a Bayesian hyper-parameter statistical method to quantify the difference between predicted velocities derived from the observed galaxy distribution in the \textit{IRAS}-PSCzz redshift survey and peculiar velocities measured using different distance indicators. In our analysis we find that the model--data comparison becomes unreliable beyond 70 \hmpc because of the inadequate sampling by \textit{IRAS} survey of prominent, distant superclusters, like the Shapley Concentration. On the other hand, the analysis of the velocity residuals show that the PSCzz gravity field provides an adequate model to the local, \le 70 \hmpc, peculiar velocity field. The hyper-parameter combination of ENEAR, SN, A1SN and SFI++ catalogues in the Bayesian framework constrains the amplitude of the linear flow to be β=0.53±0.014\beta=0.53 \pm 0.014. For an rms density fluctuations in the PSCzz galaxy number density σ8gal=0.42±0.03\sigma_8^{\rm gal}=0.42\pm0.03, we obtain an estimate of the growth rate of density fluctuations fσ8(z0)=0.42±0.033f\sigma_{8}(z\sim0) = 0.42 \pm 0.033, which is in excellent agreement with independent estimates based on different techniques.Comment: 14 pages, 32 figures, MNRAS in press, matched the MNRAS published versio
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