251 research outputs found
Consistent Quantification of Precipitate Shapes and Sizes in Two and Three Dimensions Using Central Moments
NĂ€hrstoffbilanzen fĂŒr Buchen-, Eichen-, Fichten- und KiefernbestĂ€nde bei verschiedenen NutzungsintensitĂ€ten
FĂŒr 10 Waldstandorte in Niedersachsen mit Buche, Eiche, Fichte bzw. Kiefer wurden Bilanzen des Ein- und Austrags von Calcium, Kalium, Magnesium und Stickstoff unter BerĂŒcksichtigung von 3 NutzungsintensitĂ€ten (ohne Nutzung, Derbholz-Nutzung, Vollbaum-Nutzung) berechnet. Bereits die konventionelle Derbholz-Nutzung kann erhebliche NĂ€hrstoffverluste verursachen. Der zusĂ€tzliche Entzug einer intensivierten Nutzung wĂ€re bei nĂ€hrstoffarmen Standorten und besonders fĂŒr Calcium (Fichte > Buche > Kiefer > Eiche) und Magnesium (Fichte > Kiefer > Buche > Eiche) kritisch. Bei signifikant negativen Bilanzen wĂŒrde er innerhalb von 100 Jahren bei Calcium > 90 % (Eiche > Fichte > Kiefer > Buche) und bei Magnesium > 110 % (Eiche > Fichte > Buche > Kiefer) des Umfangs einer Kalkung entsprechen. Eine Intensivierung der konventionellen Derbholz-Nutzung sollte deshalb nur auf solchen Standorten erfolgen, wo nachhaltige NĂ€hrstoffkreislĂ€ufe gesichert sind
Evaluating Depressive Symptoms in Schizophrenia: A Psychometric Comparison of the Calgary Depression Scale for Schizophrenia and the Hamilton Depression Rating Scale
Background: The aim of this study was to compare two measures of depression in patients with schizophrenia and schizophrenia spectrum disorder, including patients with delusional and schizoaffective disorder, to conclude implications for their application. Sampling and Methods: A total of 278 patients were assessed using the Calgary Depression Scale for Schizophrenia (CDSS) and the Hamilton Depression Rating Scale (HAMD-17). The Positive and Negative Syndrome Scale (PANSS) was also applied. At admission and discharge, a principal component analysis was performed with each depression scale. The two depression rating scales were furthermore compared using correlation and regression analyses. Results: Three factors were revealed for the CDSS and HAMD-17 factor component analysis. A very similar item loading was found for the CDSS at admission and discharge, whereas results of the loadings of the HAMD-17 items were less stable. The first two factors of the CDSS revealed correlations with positive, negative and general psychopathology. In contrast, multiple significant correlations were found for the HAMD-17 factors and the PANSS sub-scores. Multiple regression analyses demonstrated that the HAMD-17 accounted more for the positive and negative symptom domains than the CDSS. Conclusions:The present results suggest that compared to the HAMD-17, the CDSS is a more specific instrument to measure depressive symptoms in schizophrenia and schizophrenia spectrum disorder, especially in acutely ill patients. Copyright (c) 2012 S. Karger AG, Base
Cost Benefit Analysis of an Innovative and Modular Autonomous Vehicle: The Case of U-Shift
The study presents a Cost-Benefit Analysis (CBA) of future implementation of âU-Shiftâ vehicles. âU-Shiftâ is an autonomous vehicle concept currently developed at the German Centre for Aerospace (DLR). The CBA was prepared in 2020 as part of a feasibility study on behalf of the German Ministry for Economy to assess the possible impacts of a hypothetical large-scale implementation of these vehicles. It compares two future scenarios for roll-out in 2040 in Stuttgart, a mid-sized city in Germanyâs automotive centre, with a Base Case. Scenario 1 reflects the preferred approach for implementation pursued by DLR, where autonomous driving of vehicles is enabled by sensors as part of the road infrastructure and the vehiclesâ movements are orchestrated by a central traffic management centre. Scenario 2 reflects the current approach for automation, where autonomous driving technology is part of the vehicle itself and their movements are not coordinated by a central agency.
The CBA quantifies capital and recurrent costs, road safety, CO2 emissions and air pollution. Costs and benefits are quantified for one year only, 2040, a plausible year for large-scale implementation. As it only considers recurrent costs and benefits of one year, investment costs were apportioned accordingly, taken the expected asset life into account
Trap-integrated fluorescence detection based on silicon photomultipliers in a cryogenic Penning trap
We present a fluorescence-detection system for laser-cooled 9Be+ ions based
on silicon photomultipliers (SiPM) operated at 4 K and integrated into our
cryogenic 1.9 T multi-Penning-trap system. Our approach enables fluorescence
detection in a hermetically-sealed cryogenic Penning-trap chamber with limited
optical access, where state-of-the-art detection using a telescope and
photomultipliers at room temperature would be extremely difficult. We
characterize the properties of the SiPM in a cryocooler at 4 K, where we
measure a dark count rate below 1/s and a detection efficiency of 2.5(3) %. We
further discuss the design of our cryogenic fluorescence-detection trap, and
analyze the performance of our detection system by fluorescence spectroscopy of
9Be+ ion clouds during several runs of our experiment.Comment: 12 pages, 11 figure
BodenvorrĂ€te & Bilanzen von MakronĂ€hrstoffen als Indikatoren fĂŒr die ökologische Bewertung intensiver Biomassenutzung im Wald
Die mögliche NutzungsintensitĂ€t von WaldbestĂ€nden wird hĂ€ufig anhand einzelner Indikatoren wie den NĂ€hrstoffvorrĂ€ten im effektiven Wurzelraum (AKe), dem NĂ€hrstoffentzugsindex oder der Stoffbilanz bewertet. Dabei ergeben sich fĂŒr die hier untersuchten FlĂ€chen des Intensiven Umweltmonitorings fĂŒr Kalium und Magnesium groĂe Differenzen zwischen den betrachteten Indikatoren, dagegen fĂŒr Calcium ein eher undifferenziertes Bild. Aufgrund der uneinheitlichen Ergebnisse ist es erforderlich, die Indikatoren hinsichtlich ihrer Aussage genau zu ĂŒberprĂŒfen. Gleichzeitig sollte die Ableitung von standortspezifischen Empfehlungen fĂŒr eine angemessene NutzungsintensitĂ€t und den Bedarf an KompensationsmaĂnahmen (z. B. Kalkung) unbedingt unter BerĂŒcksichtigung aller potenziellen Indikatoren erfolgen
Renal sympathetic denervation restores aortic distensibility in patients with resistant hypertension: data from a multi-center trial
Renal sympathetic denervation (RDN) is under investigation as a treatment option in patients with resistant hypertension (RH). Determinants of arterial compliance may, however, help to predict the BP response to therapy. Aortic distensibility (AD) is a well-established parameter of aortic stiffness and can reliably be obtained by CMR. This analysis sought to investigate the effects of RDN on AD and to assess the predictive value of pre-treatment AD for BP changes. We analyzed data of 65 patients with RH included in a multicenter trial. RDN was performed in all participants. A standardized CMR protocol was utilized at baseline and at 6-month follow-up. AD was determined as the change in cross-sectional aortic area per unit change in BP. Office BP decreased significantly from 173/92â±â24/16 mmHg at baseline to 151/85â±â24/17 mmHg (pâ<â0.001) 6 months after RDN. Maximum aortic areas increased from 604.7â±â157.7 to 621.1â±â157.3 mm2 (pâ=â0.011). AD improved significantly by 33% from 1.52â±â0.82 to 2.02â±â0.93âĂâ10-3 mmHg-1 (pâ<â0.001). Increase of AD at follow-up was significantly more pronounced in younger patients (pâ=â0.005) and responders to RDN (pâ=â0.002). Patients with high-baseline AD were significantly younger (61.4â±â10.1 vs. 67.1â±â8.4 years, pâ=â0.022). However, there was no significant correlation of baseline AD to response to RDN. AD is improved after RDN across all age groups. Importantly, these improvements appear to be unrelated to observed BP changes, suggesting that RDN may have direct effects on the central vasculature
Induction level determines signature of gene expression noise in cellular systems
Noise in gene expression, either due to inherent stochasticity or to varying
inter- and intracellular environment, can generate significant cell-to-cell
variability of protein levels in clonal populations. We present a theoretical
framework, based on stochastic processes, to quantify the different sources of
gene expression noise taking cell division explicitly into account. Analytical,
time-dependent solutions for the noise contributions arising from the major
steps involved in protein synthesis are derived. The analysis shows that the
induction level of the activator or transcription factor is crucial for the
characteristic signature of the dominant source of gene expression noise and
thus bridges the gap between seemingly contradictory experimental results.
Furthermore, on the basis of experimentally measured cell distributions, our
simulations suggest that transcription factor binding and promoter activation
can be modelled independently of each other with sufficient accuracy
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