836 research outputs found
Zero-Forcing Precoding for Frequency Selective MIMO Channels with Criterion and Causality Constraint
We consider zero-forcing equalization of frequency selective MIMO channels by
causal and linear time-invariant precoders in the presence of intersymbol
interference. Our motivation is twofold. First, we are concerned with the
optimal performance of causal precoders from a worst case point of view.
Therefore we construct an optimal causal precoder, whereas contrary to other
works our construction is not limited to finite or rational impulse responses.
Moreover we derive a novel numerical approach to computation of the optimal
perfomance index achievable by causal precoders for given channels. This
quantity is important in the numerical determination of optimal precoders.Comment: Minor Revisions, mainly in introduction and problem statement.
Submitted to Signal Processin
Gesamtwirtschaftliche und unternehmerische Anpassungsprozesse in Ostdeutschland: Zweiter Bericht
Der Bericht konzentriert sich auf eine Situationsanalyse der ostdeutschen Wirtschaft in folgenden Bereichen: Landwirtschaft, Industrie, Baugewerbe, Dienstleistungsunternehmen und öffentliche Verwaltung. Die Energiewirtschaft soll später einbezogen werden. Der Bericht folgt weitgehend dem Muster des ersten Zwischenberichts. Die Institute legen, wie schon im ersten Bericht, Ergebnisse einer Volkswirtschaftlichen Gesamtrechnung für Ostdeutschland vor. Obwohl sich das Rechenwerk inzwischen auf Angaben des Statistischen Bundesamtes für das 2. Halbjahr 1990 stützen kann, ist seine Datenbasis noch recht schmal. Die in Tabelle 3 ausgewiesenen Zahlen sind als Größenordnungen zu verstehen; sie können noch nicht jene Genauigkeit beanspruchen, wie sie in der Volkswirtschaftlichen Gesamtrechnung für Westdeutschland erreicht ist. --
Gesamtwirtschaftliche und unternehmerische Anpassungsprozesse in Ostdeutschland: Vierter Bericht
Der Bundesminister ßr Wirtschaft hat mit Schreiben vom 19. Oktober 1990 dem Deutschen Institut ßr Wirtschaftsforschung, Berlin, und dem Institut ßr Weltwirtschaft, Kiel, einen Forschungsauftrag mit dem Titel "Gesamtwirtschaftliche und unternehmerische Anpassungsprozesse in Ostdeutschland " erteilt. Dabei sollen in vierteljährlicher Folge kurze Berichte geliefert werden. Die Institute legen hiermit ihren vierten Bericht vor. * Nach wie vor ist die Datenlage unbefriedigend. Das statistische Berichtssystem in Ostdeutschland befindet sich noch in der Umstellungsphase. Die Institute müssen deshalb versuchen, die Lücken auf unkonventionelle Weise zu schließen. Das geschieht vor allem durch mündliche und schriftliche Befragungen von ost- und westdeutschen Unternehmen, Wirtschaftsverbänden, staatlichen Stellen und gesellschaftlichen Organisationen sowie durch Auswertung der Fach- und Tagespresse. Der Bericht konzentriert sich auf eine Situationsanalyse der ostdeutschen Wirtschaft in folgenden Bereichen: Landwirtschaft, Energiewirtschaft, Industrie, Baugewerbe, Dienstleistungsunternehmen und öffentlicher Sektor. Darüber hinaus werden verschiedene Spezialthemen behandelt. --
Определение объема вычислительных экспериментов при решении задач оптимизационного синтеза динамических систем методом ПЛП-поиска
Даются рекомендации по выбору необходимого числа машинных экспериментов при решении конкретных задач исследования и оптимального проектирования методом ПЛП-поиска, позволяющего осуществлять глобальный квазиравномерный просмотр заданной области варьируемых параметров и применить формальные оценки из математической статистики.Recommendations about the choice of necessary number of machine experiments at the solution of specific objectives of a research and optimum design are made by method of the PLP-search allowing to carry out global quasi uniform viewing of the set area of the varied parameters and to apply formal estimates from mathematical statistics
SARS-CoV-2 Proteome-Wide Analysis Revealed Significant Epitope Signatures in COVID-19 Patients
The WHO declared the COVID-19 outbreak a public health emergency of international concern. The causative agent of this acute respiratory disease is a newly emerged coronavirus, named SARS-CoV-2, which originated in China in late 2019. Exposure to SARS-CoV-2 leads to multifaceted disease outcomes from asymptomatic infection to severe pneumonia, acute respiratory distress and potentially death. Understanding the host immune response is crucial for the development of interventional strategies. Humoral responses play an important role in defending viral infections and are therefore of particular interest. With the aim to resolve SARS-CoV-2-specific humoral immune responses at the epitope level, we screened clinically well-characterized sera from COVID-19 patients with mild and severe disease outcome using high-density peptide microarrays covering the entire proteome of SARS-CoV-2. Moreover, we determined the longevity of epitope-specific antibody responses in a longitudinal approach. Here we present IgG and IgA-specific epitope signatures from COVID-19 patients, which may serve as discriminating prognostic or predictive markers for disease outcome and/or could be relevant for intervention strategies
Direct limits for scalar field dark matter from a gravitational-wave detector
The nature of dark matter remains unknown to date, although several candidate particles are being considered in a dynamically changing research landscape1. Scalar field dark matter is a prominent option that is being explored with precision instruments, such as atomic clocks and optical cavities2–8. Here we describe a direct search for scalar field dark matter using a gravitational-wave detector, which operates beyond the quantum shot-noise limit. We set new upper limits on the coupling constants of scalar field dark matter as a function of its mass, by excluding the presence of signals that would be produced through the direct coupling of this dark matter to the beam splitter of the GEO600 interferometer. These constraints improve on bounds from previous direct searches by more than six orders of magnitude and are, in some cases, more stringent than limits obtained in tests of the equivalence principle by up to four orders of magnitude. Our work demonstrates that scalar field dark matter can be investigated or constrained with direct searches using gravitational-wave detectors and highlights the potential of quantum-enhanced interferometry for dark matter detection. © 2021, The Author(s)
Direct limits for scalar field dark matter from a gravitational-wave detector
The nature of dark matter remains unknown to date; several candidate
particles are being considered in a dynamically changing research landscape.
Scalar field dark matter is a prominent option that is being explored with
precision instruments, such as atomic clocks and optical cavities. Here we
report on the first direct search for scalar field dark matter utilising a
gravitational-wave detector, which operates beyond the quantum shot-noise
limit. We set new upper limits for the coupling constants of scalar field dark
matter as a function of its mass, by excluding the presence of signals that
would be produced through the direct coupling of this dark matter to the
beamsplitter of the GEO600 interferometer. The new constraints improve upon
bounds from previous direct searches by more than six orders of magnitude, and
are in some cases more stringent than limits obtained in tests of the
equivalence principle by up to four orders of magnitude. Our work demonstrates
that scalar field dark matter can be probed or constrained with direct searches
using gravitational-wave detectors, and highlights the potential of
quantum-enhanced interferometry for dark matter detection
HERC6 is the main E3 ligase for global ISG15 conjugation in mouse cells
Type I interferon (IFN) stimulates expression and conjugation of the ubiquitin-like modifier IFN-stimulated gene 15 (ISG15), thereby restricting replication of a wide variety of viruses. Conjugation of ISG15 is critical for its antiviral activity in mice. HECT domain and RCC1-like domain containing protein 5 (HerC5) mediates global ISGylation in human cells, whereas its closest relative, HerC6, does not. So far, the requirement of HerC5 for ISG15-mediated antiviral activity has remained unclear. One of the main obstacles to address this issue has been that no HerC5 homologue exists in mice, hampering the generation of a good knock-out model. However, mice do express a homologue of HerC6 that, in contrast to human HerC6, can mediate ISGylation. Here we report that the mouse HerC6 N-terminal RCC1-like domain (RLD) allows ISG15 conjugation when replacing the corresponding domain in the human HerC6 homologue. In addition, sequences in the C-terminal HECT domain of mouse HerC6 also appear to facilitate efficient ISGylation. Mouse HerC6 paralleled human HerC5 in localization and IFN-inducibility. Moreover, HerC6 knock-down in mouse cells abolished global ISGylation, whereas its over expression enhanced the IFNβ promoter and conferred antiviral activity against vesicular stomatitis virus and Newcastle disease virus. Together these data indicate that HerC6 is likely the functional counterpart of human HerC5 in mouse cells, suggesting that HerC6-/-mice may provide a feasible model to study the role of human HerC5 in antiviral responses
Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV
A search for pair-production of supersymmetric particles under the assumption
that R-parity is violated via a dominant LQDbar coupling has been performed
using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV.
The observed candidate events in the data are in agreement with the Standard
Model expectation. This result is translated into lower limits on the masses of
charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for
m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81
GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the
95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure
Multidisciplinary Consensus on Assessment of Unruptured Intracranial Aneurysms Proposal of an International Research Group
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