51 research outputs found

    Effizienter, flexibler und genauer Entwurf von Mehrlagen-Mikrowellenschaltungen mittels modularer Techniken

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    Mit der Erschließung neuer Frequenzbereiche und der steigenden Komplexität von Mehrlagen-Mikrowellenschaltungen steigt auch der Bedarf nach effizienten, flexiblen und genauen Entwurfsmethoden. Die vorliegende Arbeit verfolgt daher einen systematischen Ansatz zur Evaluierung von Entwurfsverfahren anhand dieser wesentlichen Kriterien. Grundidee der daraus entwickelten und anhand von Teststrukturen verifizierten Methodik ist die konsequente Modularisierung von Mikrowellensystemen mit entsprechend geeigneten Entwurfstechniken. Auf der Basis einer flexibel erweiterbaren Modulbibliothek werden komplexe Leitungsstrukturen mittels konstruktiver und elektromagnetischer Verkettung, unter Minimierung auftretender Simulationsfehler effizient modelliert, simuliert und optimiert. Auch technologische Herausforderungen bei der strukturtreuen Herstellung keramischer Mehrlagenmodule (engl. low temperature co-fired ceramics, LTCC) werden dabei quantitativ erfasst und entwurfsseitig berücksichtigt. Als wichtigstes Ergebnis neben den ausgeführten und erprobten Entwurfstechniken, konnte ausgehend vom Forschungsprojekt KERAMIS II (Keramische Mikrowellenschaltkreise für die Satellitenkommunikation) ein Schaltmatrix-Modul für einen LTCC-Substratwechsel adaptiert, aufgebaut, erfolgreich charakterisiert und zur Verifikation des modularen Entwurfsansatzes genutzt werden.With the development of new frequency ranges and the increasing complexity of multilayer microwave circuits, also increases the need for efficient, flexible and accurate design methods. The present work applies a systematic approach to the evaluation of design methods based on these essential criteria. The basic idea of the methodology developed from and verified using test structures, is the consequent modularisation of microwave systems with appropriate design techniques. Based on a flexibly extensible module library, complex transmission line structures, by means of constructive and electromagnetic concatenation, are modeled, simulated and optimized efficiently while minimizing occurring simulation errors. Also, technological challenges in the structurally accurate production of ceramic multilayer modules (low temperature co-fired ceramics, LTCC) are determined quantitatively and considered on design side. Starting from the research project KERAMIS II (ceramic microwave circuits for satellite communications), the most important outcome alongside the developed and proven design techniques, is a switch matrix module which could be adapted for an LTCC substrate exchange, produced, successfully characterized and used for the verification of the modular design approach

    On-orbit verification of a 4 × 4 switch matrix for space applications based on the low temperature co-fired ceramics technology

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    We have developed a compact, high-performance, mechanically robust reconfigurable microwave switch matrix as well as peripheral components such as diode driver, voltage controlled oscillator, and power detector modules for satellite applications using the low temperature co-fired ceramics technology (LTCC) and hybrid integration of integrated circuits. In order to verify the technology for space applications, we combined these components to build a system that enables automated verification of the switch matrix in space, accounting for power consumption, mass, overall geometrical dimensions, and mechanical robustness. The system passed a full space qualification. During a one year On-Orbit-Verification (OOV) mission aboard the German test satellite TET-1 (technology evaluation carrier) launched on July 22, 2012, the correct operation and reliability of the entire switch matrix system and thereby the used technology will be demonstrated

    Host galaxy morphologies of X-ray selected AGN: assessing the significance of different black hole fueling mechanisms to the accretion density of the Universe at z~1

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    We use morphological information of X-ray selected AGN hosts to set limits on the fraction of the accretion density of the Universe at z~1 that is not likely to be associated with major mergers. Deep X-ray observations are combined with high resolution optical data from the Hubble Space Telescope in the AEGIS, GOODS North and GOODS South fields to explore the morphological breakdown of X-ray sources in the redshift interval 0.5<z<1.3. The sample is split into disks, early-type bulge dominated galaxies, peculiar systems and point-sources in which the nuclear source outshines the host galaxy. The X-ray luminosity function and luminosity density of AGN at z~1 are then calculated as a function of morphological type. We find that disk-dominated hosts contribute 30\pm9 per cent to the total AGN space density and 23\pm6 per cent to the luminosity density at z~1. We argue that AGN in disk galaxies are most likely fueled not by major merger events but by minor interactions or internal instabilities. We find evidence that these mechanisms may be more efficient in producing luminous AGN (L_X>1e44 erg/s) compared to predictions for the stochastic fueling of massive black holes in disk galaxies.Comment: Accepted for publication in MNRA

    Predictions for cold nuclear matter effects in p plus Pb collisions at root SNN =8.16 TeV

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    Predictions for cold nuclear matter effects on charged hadrons, identified light hadrons, quarkonium and heavy flavor hadrons, Drell-Yan dileptons, jets, photons, gauge bosons and top quark pairs produced in p+Pb collisions at, root S-NN = 8.16 TeV are compiled and, where possible, compared to each other. Predictions of the normalized ratios of p+Pb to p+ p cross sections are also presented for most of the observables, providing new insights into the expected role of cold nuclear matter effects. In particular, the role of nuclear parson distribution functions on particle production can now be probed over a wider range of phase space than ever before. (C) 2018 Elsevier B.V. All rights reserved.Peer reviewe

    Olfactory Receptors in Non-Chemosensory Organs: The Nervous System in Health and Disease

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    Olfactory receptors (ORs) and down-stream functional signaling molecules adenylyl cyclase 3 (AC3), olfactory G protein \u3b1 subunit (G\u3b1olf), OR transporters receptor transporter proteins 1 and 2 (RTP1 and RTP2), receptor expression enhancing protein 1 (REEP1), and UDP-glucuronosyltransferases (UGTs) are expressed in neurons of the human and murine central nervous system (CNS). In vitro studies have shown that these receptors react to external stimuli and therefore are equipped to be functional. However, ORs are not directly related to the detection of odors. Several molecules delivered from the blood, cerebrospinal fluid, neighboring local neurons and glial cells, distant cells through the extracellular space, and the cells' own self-regulating internal homeostasis can be postulated as possible ligands. Moreover, a single neuron outside the olfactory epithelium expresses more than one receptor, and the mechanism of transcriptional regulation may be different in olfactory epithelia and brain neurons. OR gene expression is altered in several neurodegenerative diseases including Parkinson's disease (PD), Alzheimer's disease (AD), progressive supranuclear palsy (PSP) and sporadic Creutzfeldt-Jakob disease (sCJD) subtypes MM1 and VV2 with disease-, region- and subtype-specific patterns. Altered gene expression is also observed in the prefrontal cortex in schizophrenia with a major but not total influence of chlorpromazine treatment. Preliminary parallel observations have also shown the presence of taste receptors (TASRs), mainly of the bitter taste family, in the mammalian brain, whose function is not related to taste. TASRs in brain are also abnormally regulated in neurodegenerative diseases. These seminal observations point to the need for further studies on ORs and TASRs chemoreceptors in the mammalian brain

    Forty years of carabid beetle research in Europe - from taxonomy, biology, ecology and population studies to bioindication, habitat assessment and conservation

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    Volume: 100Start Page: 55End Page: 14

    Telomerecat: A ploidy-agnostic method for estimating telomere length from whole genome sequencing data.

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    Telomere length is a risk factor in disease and the dynamics of telomere length are crucial to our understanding of cell replication and vitality. The proliferation of whole genome sequencing represents an unprecedented opportunity to glean new insights into telomere biology on a previously unimaginable scale. To this end, a number of approaches for estimating telomere length from whole-genome sequencing data have been proposed. Here we present Telomerecat, a novel approach to the estimation of telomere length. Previous methods have been dependent on the number of telomeres present in a cell being known, which may be problematic when analysing aneuploid cancer data and non-human samples. Telomerecat is designed to be agnostic to the number of telomeres present, making it suited for the purpose of estimating telomere length in cancer studies. Telomerecat also accounts for interstitial telomeric reads and presents a novel approach to dealing with sequencing errors. We show that Telomerecat performs well at telomere length estimation when compared to leading experimental and computational methods. Furthermore, we show that it detects expected patterns in longitudinal data, repeated measurements, and cross-species comparisons. We also apply the method to a cancer cell data, uncovering an interesting relationship with the underlying telomerase genotype

    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    Publisher Correction: Telomerecat: A ploidy-agnostic method for estimating telomere length from whole genome sequencing data.

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    A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper
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