738 research outputs found

    On Complexity, Energy- and Implementation-Efficiency of Channel Decoders

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    Future wireless communication systems require efficient and flexible baseband receivers. Meaningful efficiency metrics are key for design space exploration to quantify the algorithmic and the implementation complexity of a receiver. Most of the current established efficiency metrics are based on counting operations, thus neglecting important issues like data and storage complexity. In this paper we introduce suitable energy and area efficiency metrics which resolve the afore-mentioned disadvantages. These are decoded information bit per energy and throughput per area unit. Efficiency metrics are assessed by various implementations of turbo decoders, LDPC decoders and convolutional decoders. New exploration methodologies are presented, which permit an appropriate benchmarking of implementation efficiency, communications performance, and flexibility trade-offs. These exploration methodologies are based on efficiency trajectories rather than a single snapshot metric as done in state-of-the-art approaches.Comment: Submitted to IEEE Transactions on Communication

    Verbale Definitheit und der vedische Injunktiv

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    Der Artikel knüpft an Karl Hoffmanns Ergebnisse zur Funktionsbestimmung des vedischen Injunktivs an und versucht anhand ausgewählter Stellen des Rigveda zu zeigen, dass der Injunktiv nicht nur ,bekannte‘ Sachverhalte bezeichnet, sondern überhaupt die ,definite‘ Weise ist, auf Sachverhalte bezugzunehmen. Mit dieser speziellen Funktion deckt der Injunktiv eine Teilmenge der Funktionen des Indikativs ab. Da der Injunktiv morphologisch aber einfacher ist als der Indikativ, sind vorhistorische Funktionsverschiebungen anzunehmen

    Prevalence of findings compatible with carotid artery calcifications on dental panoramic radiographs

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    Cerebrovascular accidents are responsible for killing or disabling more than half a million Americans every year. They are the third leading cause of death in this country. In Germany, the annual stroke incidence reaches 182 cases per 100,000 inhabitants. Stroke there is the fourth leading cause of death. There is a need of finding cost-effective means of decreasing stroke mortality and morbidity. Instruments for early diagnosis are of great humanitarian and economic importance. All possible clinical findings should be taken into account. It is not the demand of this study to present the panoramic radiograph as a screening test method for early diagnosis of atherosclerosis. The aim is to show the potential of this radiograph used in everyday clinical dental practice by the prevalence of radiopaque findings in the carotid region. This study included panoramic dental radiographs of 2,557 patients older than 30years of age. Fifty-nine percent of the patients were women and 41% were men. The radiographs were adjudged for signs compatible with carotid arterial calcifications appearing as a radiopaque nodular mass adjacent to the cervical vertebrae at or below the intervertebral space C3-4. Of all these radiographs, 4.8% showed radiopaque findings compatible with atherosclerotic lesions. The proportion of women reached 64.8% and that of men reached 35.2%. In accordance to recent literature, the results of this study show that about 5% of the patients show radiological findings compatible with carotid arterial calcifications. Some of these patients at risk for a cerebrovascular accident may be identified in the dentist's office by appropriate review of the panoramic dental radiograph. The suspicion of carotid artery calcifications demands an impetuous referral to an appropriate practitioner who can assist in the control of risk factors and if necessary arrange surgical removal of the carotid arterial plaque. So, the dentist should be aware of this problem and able to make a contribution to stroke preventio

    Vaccination against Borna Disease: Overview, Vaccine Virus Characterization and Investigation of Live and Inactivated Vaccines

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    (1) Background: Vaccination of horses and sheep against Borna disease (BD) was common in endemic areas of Germany in the 20th century but was abandoned in the early 1990s. The recent occurrence of fatal cases of human encephalitis due to Borna disease virus 1 (BoDV-1) has rekindled the interest in vaccination. (2) Methods: The full genomes of the BD live vaccine viruses “Dessau” and “Giessen” were sequenced and analyzed for the first time. All vaccination experiments followed a proof-of-concept approach. Dose-titration infection experiments were performed in rabbits, based on both cell culture- and brain-derived viruses at various doses. Inactivated vaccines against BD were produced from concentrated cell culture supernatants and investigated in rabbits and horses. The BoDV-1 live vaccine “Dessau” was administered to horses and antibody profiles were determined. (3) Results: The BD live vaccine viruses “Dessau” and “Giessen” belong to clusters 3 and 4 of BoDV-1. Whereas the “Giessen” virus does not differ substantially from field viruses, the “Dessau” virus shows striking differences in the M gene and the N-terminal part of the G gene. Rabbits infected with high doses of cell-cultured virus developed neutralizing antibodies and were protected from disease, whereas rabbits infected with low doses of cell-cultured virus, or with brain-derived virus did not. Inactivated vaccines were administered to rabbits and horses, following pre-defined vaccination schemes consisting of three vaccine doses of either adjuvanted or nonadjuvanted inactivated virus. Their immunogenicity and protective efficacy were compared to the BD live vaccine “Dessau”. Seventy per cent of horses vaccinated with the BD live vaccine “Dessau” developed neutralizing antibodies after vaccination. (4) Conclusion: Despite a complex evasion of immunological responses by bornaviruses, some vaccination approaches can protect against clinical disease. For optimal effectiveness, vaccines should be administered at high doses, following vaccination schemes consisting of three vaccine doses as basic immunization. Further investigations are necessary in order to investigate and improve protection against infection and to avoid side effects

    Bathymetric and Seismic Data, Heat Flow Data, and Age Constraints of Le Gouic Seamount, Northeastern Atlantic

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    Until the year 2019 only around 15% of the Earth’s seafloor were mapped at fine spatial resolution (<800 m) by multibeam echosounder systems (Wölfl et al., 2019). Most of our knowledge of global bathymetry is based on depths predicted by gravity observations from satellite altimeters. These predicted depths are combined with shipboard soundings to produce global bathymetric grids. The first topographic map of the world’s oceans so produced (Smith and Sandwell, 1997) had a resolution between 1 and 12 km, and subsequent improvements in data and filtering techniques led to several updates. The latest bathymetric grid of the General Bathymetric Chart of the Oceans (GEBCO_2020) uses the SRTM15+V2.0 data set, which has a grid spacing of 15 arc sec, equivalent to about 500 × 500 m at the equator (Tozer et al., 2019). This resolution does not imply that reliable depth data are available for each grid cell. There are vast areas of the oceans where the accuracy of these grids is limited by lacking shipborne multibeam data, which are needed for calibrating and ground-truthing predicted depths (Smith and Sandwell, 1994). The resolution and accuracy of the bathymetric grids are critical factors for global estimates of the number and size distribution of seamounts, in particular for small edifices of <1,000 m height (Wessel, 2001; Hillier and Watts, 2007; Kim and Wessel, 2011). A case in point is Le Gouic Seamount, located in the NE Atlantic about 100 km SW of Tropic Seamount on ca. 152 Ma crust, close to magnetic isochrone M24 (Bird et al., 2007). The seamount belongs to the Canary Island Seamount Province (CISP; van den Bogaard, 2013), also termed Western Saharan Seamount Province (WSSP) by some workers (e.g., Josso et al., 2019). It is listed in the Kim and Wessel (2011) seamount census with the ID KW-00902, located at 21.26216 ◦ W/23.0199 ◦ N, with a height of 498 m; hence it appears as a tiny cone in pre-2019 bathymetric grids (Figure 1a). After first mapping of large parts of the seamount by the French oceanographic survey vessel “Beautemps-Beaupré” in 2013, it is represented at its full height in the actual GEBCO_2020 grid, which is based on the SRTM15+V2.0 data set (Tozer et al., 2019). In this data report we present new multibeam bathymetric data for Le Gouic Seamount, mapping its full extent for the first time. The data were obtained during a transit of R/V METEOR cruise M146 in 2018. We also present a reflection seismic profile across the seamount that was shot during the mapping, and seafloor heatflow data obtained on a profile near the northeastern seamount base and co-located on the reflection profile. On the basis of this data we can place constraints on the age of the seamount, and speculate about possible rejuvenated magmatic activity

    Prevalence of Pulmonary Tuberculosis among Prison Inmates in Ethiopia, a Cross-Sectional Study

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    Setting Tuberculosis (TB) is one of the major health problems in prisons. Objective This study was done to assess the prevalence and determinants of active tuberculosis in Ethiopian prisons. Design A cross-sectional study was conducted from January 2013 to December 2013 in 13 zonal prisons. All incarcerated inmates underwent TB symptom screening according to WHO criteria. From identified TB-suspects two sputum samples were analyzed using smear microscopy and solid culture. A standardized questionnaire assessing TB risk factors was completed for each TB suspect. Results 765 (4.9%) TB suspects were identified among 15, 495 inmates. 51 suspects were already on anti-TB treatment (6.67%) and 20 (2.8%) new culture-confirmed TB cases were identified in the study, resulting in an overall TB prevalence of 458.1/100, 000 (95% CI: 350-560/100, 000). Risk factors for active TB were alcohol consumption, contact with a TB case before incarceration and no window in prison cell. HIV prevalence was not different between TB suspects and active TB cases. Further, the TB burden in prisons increased with advancing distance from the capital Addis Ababa. Conclusions The overall TB prevalence in Ethiopian prisons was high and extremely variable among different prisons. TB risk factors related to conditions of prison facilities and the impact of implemented TB control measures need to be further studied in order to improve TB control among inmates

    Hydrothermal Activity at a Cretaceous Seamount, Canary Archipelago, Caused by Rejuvenated Volcanism

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    Our knowledge of venting at intraplate seamounts is limited. Almost nothing is known about past hydrothermal activity at seamounts, because indicators are soon blanketed by sediment. This study provides evidence for temporary hydrothermal circulation at Henry Seamount, a re-activated Cretaceous volcano near El Hierro island, close to the current locus of the Canary Island hotspot. In the summit area at around 3000–3200 m water depth, we found areas with dense coverage by shell fragments from vesicomyid clams, a few living chemosymbiotic bivalves, and evidence for sites of weak fluid venting. Our observations suggest pulses of hydrothermal activity since some thousands or tens of thousands years, which is now waning. We also recovered glassy heterolithologic tephra and dispersed basaltic rock fragments from the summit area. Their freshness suggests eruption during the Pleistocene to Holocene, implying minor rejuvenated volcanism at Henry Seamount probably related to the nearby Canary hotspot. Heat flow values determined on the surrounding seafloor (49 ± 7 mW/m 2 ) are close to the expected background for conductively cooled 155 Ma old crust; the proximity to the hotspot did not result in elevated basal heat flow. A weak increase in heat flow toward the southwestern seamount flank likely reflects recent local fluid circulation. We propose that hydrothermal circulation at Henry Seamount was, and still is, driven by heat pulses from weak rejuvenated volcanic activity. Our results suggest that even single eruptions at submarine intraplate volcanoes may give rise to ephemeral hydrothermal systems and generate potentially habitable environments

    miRNA Signatures in Sera of Patients with Active Pulmonary Tuberculosis.

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    Several studies showed that assessing levels of specific circulating microRNAs (miRNAs) is a non-invasive, rapid, and accurate method for diagnosing diseases or detecting alterations in physiological conditions. We aimed to identify a serum miRNA signature to be used for the diagnosis of tuberculosis (TB). To account for variations due to the genetic makeup, we enrolled adults from two study settings in Europe and Africa. The following categories of subjects were considered: healthy (H), active pulmonary TB (PTB), active pulmonary TB, HIV co-infected (PTB/HIV), latent TB infection (LTBI), other pulmonary infections (OPI), and active extra-pulmonary TB (EPTB). Sera from 10 subjects of the same category were pooled and, after total RNA extraction, screened for miRNA levels by TaqMan low-density arrays. After identification of "relevant miRNAs", we refined the serum miRNA signature discriminating between H and PTB on individual subjects. Signatures were analyzed for their diagnostic performances using a multivariate logistic model and a Relevance Vector Machine (RVM) model. A leave-one-out-cross-validation (LOOCV) approach was adopted for assessing how both models could perform in practice. The analysis on pooled specimens identified selected miRNAs as discriminatory for the categories analyzed. On individual serum samples, we showed that 15 miRNAs serve as signature for H and PTB categories with a diagnostic accuracy of 82% (CI 70.2-90.0), and 77% (CI 64.2-85.9) in a RVM and a logistic classification model, respectively. Considering the different ethnicity, by selecting the specific signature for the European group (10 miRNAs) the diagnostic accuracy increased up to 83% (CI 68.1-92.1), and 81% (65.0-90.3), respectively. The African-specific signature (12 miRNAs) increased the diagnostic accuracy up to 95% (CI 76.4-99.1), and 100% (83.9-100.0), respectively. Serum miRNA signatures represent an interesting source of biomarkers for TB disease with the potential to discriminate between PTB and LTBI, but also among the other categories
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