548 research outputs found
Multiple Rotations of Gaussian Quadratures: An Efficient Method for Uncertainty Analyses in Large-Scale Simulation Models
Concerns regarding the impact of climate change, food price volatility, and weather uncertainty have motivated users of simulation models to consider uncertainty in their simulations. One way to do this is to integrate uncertainty components in the model equations, thus turning the model into a problem of numerical integration. Most of these problems do not have analytical solutions, and researchers, therefore, apply numerical approximation methods. This article presents a novel approach to conducting an uncertainty analysis as an alternative to the computationally burdensome Monte Carlo-based (MC) methods. The developed method is based on the degree three Gaussian quadrature (GQ) formulae and is tested using three large-scale simulation models. While a standard single GQ method often produces low-quality approximations, the results of this study demonstrate that the proposed approach reduces the approximation errors by a factor of nine using only 3.4% of the computational effort required by the MC-based methods in the most computationally demanding model
Neuroendocrine Tumors of the Bronchopulmonary System (Typical and Atypical Carcinoid Tumors): Current Strategies in Diagnosis and Treatment. Conclusions of an Expert Meeting February 2011 in Weimar, Germany
Neuroendocrine tumors (NETs; syn. carcinoid tumors) are highly or moderately differentiated neoplasms. They comprise a large variety of rare and heterogeneous tumors with an estimated incidence of 3-5/100,000/year. They can arise in virtually every internal organ, but mainly occur in the gastroenteropancreatic and bronchopulmonary systems. Around 25% of the NETs are localized in the bronchopulmonary system. Approximately 2% of all lung tumors are NETs. According to the World Health Organization (WHO) classification of lung tumors, bronchopulmonary NETs are subdivided into typical carcinoids (TCs) and atypical carcinoids (ACs). The parameter with the highest impact on NET behavior and prognosis is the histological classification and staging according to the tumor/node/metastasis (TNM) system. The diagnosis of NETs is established by histological examination and the immunohistochemical detection of general neuroendocrine markers, such as chromogranin A (CgA) and synaptophysin. Serum markers and the use of functional imaging techniques are important additive tools to establish the diagnosis of a NET. The only curative option for lung NETs is complete surgical resection. Beyond that, the currently available interdisciplinary therapeutic options are local ablation, biotherapy (somatostatin analogues), or chemotherapy. New therapeutic options such as peptide receptor radionuclide therapy (PRRT) and molecularly targeted therapies achieve promising results and are under further evaluation. This report is a consensus summary of the interdisciplinary symposium âNeuroendocrine Tumors of the Lung and of the Gastroenteropancreatic System (GEP NET) - Expert Dialogue' held on February 25-26, 2011 in Weimar, Germany. At this conference, a panel of 23 German experts shared their knowledge and exchanged their thoughts about research, diagnosis, and clinical management of NETs, whereby special attention was paid to NETs of the respiratory trac
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Instrumente und MaĂnahmen der kommunalen Klimaanpassung: Empirische Befunde fĂŒr einen erfolgreichen Transfer
Der vorliegende Bericht untersucht Lern- und Transferprozesse zwischen sowie innerhalb von StĂ€dten sowie das Transferpotenzial konkreter Wissenstransfer-Medien, Instrumente und MaĂnahmen. Damit wird das Ziel verfolgt, ein besseres VerstĂ€ndnis dieser Prozesse zu entwickeln und einen Beitrag zur Verbesserung des Transfers von kommunalen KlimaanpassungsaktivitĂ€ten zu leisten. Er baut dabei auf einer vorangegangenen Analyse des Forschungsstands zum Transfer von Policies durch Haupt et al. (2021) auf und versucht, den bereits generierten Wissensstand auf der Ebene von Policies nun um die Ebene konkreter Instrumente und MaĂnahmen zu ergĂ€nzen sowie durch empirische Befunde zu ausgewĂ€hlten MaĂnahmen zu untermauern. Die Wissens- und Datengrundlage dieses Berichts umfasst einen Mix aus verschiedenen (Online)-Befragungen und Interviews mit Vertreter:innen relevanter Akteursgruppen, vor allem Vertreter:innen von Stadtverwaltungen, sowie den Erfahrungswerten der drei Projekt-FallstudienstĂ€dte Potsdam, Remscheid und WĂŒrzburg
A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)
We present a measurement of time-dependent CP-violating asymmetries in
neutral B meson decays collected with the BABAR detector at the PEP-II
asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data
sample consists of 29.7 recorded at the
resonance and 3.9 off-resonance. One of the neutral B mesons,
which are produced in pairs at the , is fully reconstructed in
the CP decay modes , , , () and , or in flavor-eigenstate
modes involving and (). The flavor of the other neutral B meson is tagged at the time of
its decay, mainly with the charge of identified leptons and kaons. The proper
time elapsed between the decays is determined by measuring the distance between
the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample
finds . The value of the asymmetry amplitude is determined from
a simultaneous maximum-likelihood fit to the time-difference distribution of
the flavor-eigenstate sample and about 642 tagged decays in the
CP-eigenstate modes. We find , demonstrating that CP violation exists in the neutral B meson
system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review
Measurement of the branching fraction and CP content for the decay B(0) -> D(*+)D(*-)
This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APS.We report a measurement of the branching fraction of the decay B0âD*+D*- and of the CP-odd component of its final state using the BABAR detector. With data corresponding to an integrated luminosity of 20.4ââfb-1 collected at the ΄(4S) resonance during 1999â2000, we have reconstructed 38 candidate signal events in the mode B0âD*+D*- with an estimated background of 6.2±0.5 events. From these events, we determine the branching fraction to be B(B0âD*+D*-)=[8.3±1.6(stat)±1.2(syst)]Ă10-4. The measured CP-odd fraction of the final state is 0.22±0.18(stat)±0.03(syst).This work is supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the A.P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation
Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events
The - oscillation frequency has been measured with a sample of
23 million \B\bar B pairs collected with the BABAR detector at the PEP-II
asymmetric B Factory at SLAC. In this sample, we select events in which both B
mesons decay semileptonically and use the charge of the leptons to identify the
flavor of each B meson. A simultaneous fit to the decay time difference
distributions for opposite- and same-sign dilepton events gives ps.Comment: 7 pages, 1 figure, submitted to Physical Review Letter
Red blood cell-derived semaphorin 7A promotes thrombo-inflammation in myocardial ischemia-reperfusion injury through platelet GPIb.
Myocardial ischemia is one of the leading health problems worldwide. Therapy consists of the restitution of coronary perfusion which is followed by myocardial inflammation. Platelet-neutrophil interaction is a crucial process during inflammation, yet its consequences are not fully understood. Here, we show that platelet-neutrophil complexes (PNCs) are increased in patients with acute myocardial infarction and that this is associated with increased levels of neuronal guidance protein semaphorin 7A (SEMA7A). To investigate this further, we injected WT animals with Sema7a and found increased infarct size with increased numbers of PNCs. Experiments in genetically modified animals identify Sema7a on red blood cells to be crucial for this condition. Further studies revealed that Sema7a interacts with the platelet receptor glycoprotein Ib (GPIb). Treatment with anti-Sema7a antibody protected from myocardial tissue injury. In summary, we show that Sema7a binds to platelet GPIb and enhances platelet thrombo-inflammatory activity, aggravating post-ischemic myocardial tissue injury
Measurement of D-s(+) and D-s(*+) production in B meson decays and from continuum e(+)e(-) annihilation at âs=10.6 GeV
This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APSNew measurements of Ds+ and Ds*+ meson production rates from B decays and from qqÌ
continuum events near the ΄(4S) resonance are presented. Using 20.8 fb-1 of data on the ΄(4S) resonance and 2.6 fb-1 off-resonance, we find the inclusive branching fractions B(BâDs+X)=(10.93±0.19±0.58±2.73)% and B(BâDs*+X)=(7.9±0.8±0.7±2.0)%, where the first error is statistical, the second is systematic, and the third is due to the Ds+âÏÏ+ branching fraction uncertainty. The production cross sections Ï(e+e-âDs+X)ĂB(Ds+âÏÏ+)=7.55±0.20±0.34pb and Ï(e+e-âDs*±X)ĂB(Ds+âÏÏ+)=5.8±0.7±0.5pb are measured at center-of-mass energies about 40 MeV below the ΄(4S) mass. The branching fractions ÎŁB(BâDs(*)+D(*))=(5.07±0.14±0.30±1.27)% and ÎŁB(BâDs*+D(*))=(4.1±0.2±0.4±1.0)% are determined from the Ds(*)+ momentum spectra. The mass difference m(Ds+)-m(D+)=98.4±0.1±0.3MeV/c2 is also measured.This work was supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the Swiss NSF, A. P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation
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