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Water as a Standard Substance of a Logarithmic Poison Scale

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Journal of Biosciences and Medicines 2024年第1期12卷 86-92页

作者： karsten Strey Scientific Writer Hamburg Germany

The lethal dose LD50 represents the most important experimental value for acute toxicity. The simple logarithmic calculation of -log10 LD50 = value leads to the possible poison power pLD. As with the pH or pK value, respectively, for acid or the scale of earthquake intensities the logarithm helps making large differences of orders of magnitude easier to understand since they are more comparable. The higher the pLD value, the higher is the power of poison. An increase of the pLD value by 1 stands for a tenfold increase in toxicity. The lethal acute dose for water, one of the most important and at the same time non-toxic substances of all, is about one tenth of the body weight. This leads to a possible pLD value for water of 1, an ideal starting value for a logarithmic poison scale.

关键词： LD50 Lethal Dose Toxicity Water Glyphosate Poison Scale

Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

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Journal of Sport and Health Science 2024年第3期13卷 288-296,I0002页

作者： Tim Böttrich Pascal Bauer Vincent Gröβer Magdalena Huber Hartmann Raifer Torsten Frech Svenja Nolte Theresa Dombrowski Franz Cemic Natascha Sommer Robert Ringseis Klaus Eder karsten Krüger Christopher Weyh Department of Exercise Physiology and Sports Therapy Institute of Sports ScienceJustus-Liebig-UniversityGiessen 35394Germany Department of Cardiology and Angiology Justus-Liebig-University GiessenGiessen 35392Germany Institute for Systems Immunology Center for Tumor und ImmunologyMarburg 35032Germany TH Mittelhessen Department of Computer ScienceUniversity of Applied Sciences GiessenGiessen 35390Germany Department of Internal Medicine Universities of Giessen and Marburg Lung Center(UGMLC)Member of the German Center for Lung Research(DZL)Giessen 35394Germany Excellence Cluster Cardio-Pulmonary Institute(CPI) Justus-Liebig UniversityGiessen 35394Germany Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenGiessen 35390Germany

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular *** pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early *** is evidence that regulatory T cells(Tregs)are involved in the development of ***,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated ***:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking *** of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were ***,tests were conducted to assess blood lipids and determine glucose *** of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow *** were categorized according to atherosclerotic plaque *** and logistic regression models were used to analyze associations between ***:SAP was detected in a total of 29 *** participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and

关键词： Cardiorespiratory fitness Elderly Regulatory T cells Subclinical atherosclerosis

Gottfried Konecny:The photogrammetric and remote sensing trend setter

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Geo-Spatial Information Science 2021年第1期24卷 13-21,I0004页

作者： karsten Jacobsen Institute of Photogrammetry and Geoinformation Leibniz University HannoverHannoverGermany

There are various publications on the 90th birthday of Gottfried *** involvement in the International Society for Photogrammetry and Remote Sensing(ISPRS)is particularly described by ***,his forward-oriented impulses in research and development at the former Institute for Photogrammetry and Engineering Survey of the(Technical)University of Hannover,today Institute for Photogrammetry and Geoinformation,Leibniz University Hannover,and some of his activities supporting developing and other countries by given shortterm courses are *** Konecny was always one of the first in pushing new *** the analytical plotter AP/C-3,he introduced analytical photogrammetry in *** on his experience with this not really operational version,he induced the company Zeiss to develop the first really operational analytical plotter Planicomp,which resulted in the end of analog photogrammetric devices and their *** the invitation of Gilbert Hobrough,a mainly hardware-based image correlator was developed for the AP/C-3 in Hannover which anticipated many of today’s *** Konecny initiated remote sensing in *** on his proposal with the Metric Camera Flight on Spacelab,the then highest resolution civil stereoscopic space images available were *** limited computer performance at his institute,a digital stereo plotter was developed,using hardware components from the cooperating Swedish company Context Vision,long before digital stereo workstations with increased and affordable computer capacity were ***,in the area of GIS,he too,pushed development in collaboration with companies and *** before the end of his time as head of the institute,and more so after he became emeritus professor,he started a series of educational workshops,particularly in developing countries,but also other countries,to support the development of photogrammetry,remote sensing and *** prom

关键词： initiated gramme hardware

Turbulence model performance for ventilation components pressure losses

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Building Simulation 2022年第3期15卷 389-399页

作者： karsten Tawackolian Martin Kriegel Hermann-Rietschel-Institut EnergyComfort&Health in BuildingsTU BerlinGermany

This study looks to find a suitable turbulence model for calculating pressure losses of ventilation *** building ventilation,the most relevant Reynolds number range is between 3×10^(4) and 6×10^(5),depending on the duct dimensions and airflow *** loss coefficients can increase considerably for some components at Reynolds numbers below 2×10^(5).An initial survey of popular turbulence models was conducted for a selected test case of a bend with such a strong Reynolds number *** of the turbulence models failed in reproducing this dependence and predicted curve progressions that were too flat and only applicable for higher Reynolds *** effects near walls played an important role in the present *** turbulence modelling,near-wall damping functions are used to account for this influence.A model that implements near-wall modelling is the lag elliptic blending k-ε*** model gave reasonable predictions for pressure loss coefficients at lower Reynolds *** example is the low Reynolds number k-εturbulence model of Wilcox(LRN).The modification uses damping functions and was initially developed for simulating profiles such as aircraft *** has not been widely used for internal flows such as air duct *** on selected reference cases,the three closure coefficients of the LRN model were adapted in this work to simulate ventilation *** predictions were obtained with new coefficients(LRNM model).This underlined that low Reynolds number effects are relevant in ventilation ductworks and give first insights for suitable turbulence models for this *** the lag elliptic blending model and the modified LRNM model predicted the pressure losses relatively well for the test case where the other tested models failed.

关键词： HVAC ductwork CFD simulation turbulence model model calibration

Improving contrast and sectioning power in confocal imaging by third harmonic generation in SiOx nanocrystallites

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Chinese Optics Letters 2007年第8期5卷 477-479页

作者： Gilbert Boyer karsten Plamann Laboratoire d'Optique Appliqude Ecole Polytechnique-Ecole Nationale Supérieure de Techniques A vancdes-CNRS UMR 7639 Centre de l'Yvette chemin de la Hunière 91761 Palaiseau cedex France

We present a new optical microscope in which the light transmitted by a sample-scanned transmission confocal microscope is frequency-tripled by SiOx nanocrystallites in lieu of being transmitted by a confocal pinhole. This imaging technique offers an increased contrast and a high scattered light rejection. It is demonstrated that the contrast close to the Sparrow resolution limit is enhanced and the sectioning power are increased with respect to the linear confocal detection mode. An experimental implementation is presented and compared with the conventional linear confocal mode.

关键词： mode Improving contrast and sectioning power in confocal imaging by third harmonic generation in SiO_x nanocrystallites THG

Running‑In Behavior of Wet Multi‑plate Clutches:Introduction of a New Test Method for Investigation and Characterization

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 152-160页

作者： Katharina Voelkel Hermann Pflaum karsten Stahl Gear Research Centre(FZG) Technical University of MunichGarchingGermany

Wet multi-plate clutches are relevant components of modern drivetrain applications,not only in terms of function but also safety and *** at the beginning of their lifetime,distinct changes of the friction behavior may occur and make the actuation of the clutch *** transcript describes the typical running-in behavior of wet multi-plate clutches and gives a general definition for running-in of ***,a new test method to systematically investigate the running-in behavior of clutches is *** test method contains a test procedure to characterize the running-in behavior on different load ***,a multi-stage procedure to evaluate and characterize the running-in behavior of clutches with mathematical approaches and new characteristic values is *** quality of the test method is demonstrated on the example of three different tribological systems from dual clutch transmissions(DCT)and automatic transmissions(AT)application using paper friction linings.

关键词： Clutch Running-in Test method Paper friction lining

Investigation of the steam-cooled blade in a steam turbine cascade

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航空动力学报 2007年第5期22卷 673-682页

作者： Dieter Bohn Jing Ren karsten Kusterer Institute of Steam and Gas Turbines RWTH Aachen UniversityTemplergraben 55 D-52056 Aachen Germany B＆B-AGEMA Gesellschaft far Energietechnische Maschinenund Anlage GmbH Jülicher Strasse 338 52070 Aachen Germany

With the increasing demand for electricity,an efficiency improvement and thereby reduced CO2 emissions of the coal-fired plants are expected in order to reach the goals set in the Kyoto *** can be achieved by a rise of the process ***,live steam pressures and temperatures up to 300 bars and 923 K are planned as the next *** circuit steam cooling of blades and vanes in modern steam turbines is a promising technology in order to establish elevated live steam temperatures in future steam turbine *** this paper,a steam-cooled test vane in a cascade with external hot steam flow is analyzed numerically with the in-house code CHTflow.A parametric analysis aiming to improve the cooling effectiveness is carried out by varying the cooling mass flow *** results from two investigated cases show that the steam cooling technique has a good application potential in the steam *** internal part of the vane is cooled homogeneously in both *** the increased cooling mass flow rate,there is a significant improvement of cooling efficiency at the leading *** results show that the increased cooling mass flow ratio can enhance the cooling effectiveness at the leading *** respect to trailing edge,there is no observable improvement of cooling effectiveness with the increased cooling mass *** implies that due to the limited dimension at the trailing edge,the thermal stress cannot be decreased by increasing the cooling mass flow ***,impingement-cooling configuration at the trailing edge might be a solution to overcome the critical thermal stress *** is also observed that the performance of the cooling effective differs on pressure side and suction *** implicates that the equilibrium of the cooling effectiveness on two sides are influenced by a coupled relationship between cooling mass flow ratio and hole *** future work,optimizing the hole geometry and cooling steam supply conditions might b

关键词：蒸汽轮机层叠蒸汽冷却调查研究翼热转移

Function of the uropygial gland in eiders (Somateria mollissima)

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Avian Research 2019年第3期10卷 330-335页

作者： Anders Pape Moller karsten Laursen Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University Beijing 100875China Ecologie Systématique Evolution Université Paris-SudCNRSAgroParisTechUniversité Paris-Saclay91405 Orsay CedexFrance Department of Bioscience Aarhus UniversityGrenavej 14Kalo 8410 RandeDenmark

Background:The uropygial gland is an exocrine gland located above the tail of birds that produces a diverse range of *** has been hypothesized to be involved in chemical protection,water-proofing and maintenance of plumage *** these not necessarily mutually exclusive functions have received some empirical support,there has been little empirical research on the function of ***:Here we analyzed data for 229 individual eiders(Somateria mollissima)collected by Danish hunters during ***:The Eider is a sea-duck that spends almost its entire life in sea water emphasizing water-proofing of the *** size of the uropygial gland increased with body mass in males,but not in females,and it increased with *** size of the uropygial gland decreased during winter. Eiders with small uropygial glands grew their feathers at a fast *** with large wing areas had large uropygial glands. Conclusions:These findings are consistent with large uropygial glands playing a role in water-proofing during molt and foraging, but also that uropygial glands may play a role in chemical defense.

关键词： Anti-microbial substance Eider Somateria mollissima Uropygial gland Water-proofing

Snapshots of a Viral RNA Polymerase Switching Gears from Transcription Initiation to Elongation

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Virologica Sinica 2013年第6期28卷 337-344页

作者： karsten Theis Westfield State University Department of Chemical and Physical Sciences

During transcription initiation,RNA polymerase binds tightly to the promoter DNA defining the start of transcription,transcribes comparatively slowly,and frequently releases short transcripts(3-8 nucleotides)in a process called abortive *** to elongation,the second phase of transcription,the polymerase dissociates from the promoter while RNA synthesis *** is characterized by higher rates of transcription and tight binding to the RNA *** RNA polymerase from enterophage T7 (T7 RNAP) has been used as a model to understand the mechanism of transcription in general,and the transition from initiation to elongation *** single-subunit enzyme undergoes dramatic conformational changes during this transition to support the changing requirements of nucleic acid interactions while continuously maintaining polymerase *** structures,available of multiple stages of the initiation complex and of the elongation complex,combined with biochemical and biophysical data,offer molecular detail of the *** of the crystal structures contain a variant of T7 RNAP where proline 266 is substituted by *** variant shows less abortive products and altered timing of transition,and is a valuable tool to study these *** structural transitions from early to late initiation are well understood and are consistent with solution *** timing of events and the structural intermediates in the transition from late initiation to elongation are less well understood,but the available data allows one to formulate testable models of the transition to guide further research.

关键词： RNA polymerase Transcription Elongation Crystal structure