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Sediment generation and soil mound denudation in areas of high-density tree throw along a river valley in the jura Mountains, Switzerland

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journal of Mountain Science 2021年第2期18卷 377-391页

作者： Philip GREENWOOD jan BAUER nikolaus j kuhn Physical Geography&Environmental Change Research Group Department of Environmental SciencesUniversity of BaselKlingelbergstrasse 27Basel-4056Switzerland

A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous jura region of northwest *** aims of the work were to assess sediment generation and annual sediment... 详细信息

A preliminary field-based investigation was undertaken in a small(jura region of northwest *** aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring *** the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 *** tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(***,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(jority of tree throws,but instead,could be associated with root *** the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once tr

关键词： Tree throw Hillslope processes Sediment generation mechanism Sediment transport rate Soil mound Ibach river valley

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利用土壤颗粒的沉降粒级研究泥沙的迁移与分布规律

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土壤学报 2017年第5期54卷 1115-1124页

作者：胡亚鲜 nikolaus j.kuhn 西北农林科技大学水土保持研究所陕西杨凌712100 中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室陕西杨凌712100 瑞士巴塞尔大学环境科学系

了解不同粒径泥沙迁移运动规律,有助于深入理解侵蚀条件下碳、氮、磷等元素的生物地球化学过程。土壤营养元素的迁移转化与泥沙颗粒的运动规律密切相关,而泥沙的运动规律由颗粒大小、性状、孔隙度和密度等因素共同决定。依据泥沙颗粒沉... 详细信息

了解不同粒径泥沙迁移运动规律,有助于深入理解侵蚀条件下碳、氮、磷等元素的生物地球化学过程。土壤营养元素的迁移转化与泥沙颗粒的运动规律密切相关,而泥沙的运动规律由颗粒大小、性状、孔隙度和密度等因素共同决定。依据泥沙颗粒沉降速度分选的原理,针对中国两种典型侵蚀土壤(红壤和黄绵土),分别进行了土壤机械组成(矿质土粒分选)和沉降速度分选测定。结果表明,土壤颗粒的沉降粒级可有效区分红壤和黄绵土中不同粒径团聚体的沉降速度,能够更加准确地反映出同一粒径颗粒因性状、密度和孔隙度的差异而形成的不同沉降速度。相对于质地疏松的黄绵土,红壤的机械组成显示,有86.9%的有机碳与≤32μm的矿物颗粒相结合,很有可能随悬移过程汇入下游水体。但土壤颗粒沉降速度分布表明,约有90.5%的红壤有机碳与等效石英粒径≥63μm的团聚体相结合,易在经历较短的迁移过程后,快速沉积于下坡面。这表明,现有的土壤侵蚀模型大多利用土壤机械组成(即矿质粒径大小)在反映泥沙运动或元素迁移规律方面存在片面性。土壤的团聚过程可有效缩减有机碳和无机碳的迁移距离,从而使其更易沉积于陆生环境。土壤颗粒的沉降速度分级对认识泥沙颗粒和养分元素在侵蚀—迁移—沉积过程中的生物地球化学过程提供了新的途径和视角。

关键词：沉降管法沉降速度团聚体迁移距离有机碳无机碳

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Human intestinal acyl-CoA synthetase 5 is sensitive to the inhibitor triacsin C

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World journal of Gastroenterology 2011年第44期17卷 4883-4889页

作者： Elke Kaemmerer Anne Peuscher Andrea Reinartz Christian Liedtke Ralf Weiskirchen jürgen Kopitz nikolaus Gassler Department of Pediatrics RWTH Aachen UniversityAachenGermany Institute of Pathology RWTH Aachen University Department of Plant Biotechnology Fraunhofer Institute for Molecular Biology and Applied Ecology (IME) Institute of Pathology RWTH Aachen University Department of Medicine Ⅲ RWTH Aachen University Institute of Clinical Chemistry and Pathobiochemistry RWTH Aachen University Institute of Pathology University of Heidelberg

AIM:To investigate whether human acyl-CoA synthetase 5(ACSL5) is sensitive to the ACSL inhibitor triacsin ***:The ACSL isoforms ACSL1 and ACSL5 from rat as well as human ACSL5 were cloned and recombinantly expressed as 6xHis-tagged *** 2+-affinity purified recombinant enzymes were assayed at pH 7.5 or pH 9.5 in the presence or absence of triacsin *** addition,ACSL5 transfected CaCo2 cells and intestinal human mucosa were ***5 expression in cellular systems was verified using Western blot and *** ACSL assay mix included TrisHCl(pH 7.4),ATP,CoA,EDTA,DTT,MgCl 2,[9,103 H] palmitic acid,and triton *** 200 μL reaction was initiated with the addition of solubilized,purified recombinant proteins or cellular *** were terminated after 10,30 or 60 min of incubation with Doles ***:Expression of soluble recombinant ACSL proteins was found after incubation with isopropyl betaD-1-thiogalactopyranoside and after ultracentrifugation these were further purified to near homogeneity with Ni 2+-affinity *** C selectively and strongly inhibited recombinant human ACSL5 protein at pH 7.5 and pH 9.5,as well as recombinant rat ACSL1(sensitive control),but not recombinant rat ACSL5(insensitive control).The IC50 for human ACSL5 was about 10 μmol/*** inhibitory triacsin C effect was similar for different incubation times(10,30 and 60 min) and was not modified by the N-or C-terminal location of the *** order to evaluate ACSL5 sensitivity to triacsin C in a cellular environment,stable human ACSL5 CaCo2 transfectants and mechanically dissected normal human intestinal mucosa with high physiological expression of ACSL5 were *** both models,ACSL5 peak activity was found at pH 7.5 and pH 9.5,corresponding to the properties of recombinant human ACSL5 *** the presence of triacsin C(25 μmol/L),total ACSL activity was dramatically diminished in human ACSL5 transfectants as well as in AC

关键词： Acyl-CoA synthetase 5 Fatty acid metabolism Mitochondria Triacsin C

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Transcatheter mitral valve repair is feasible and effective in oldest-old patients:results from real-world cohort

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journal of Geriatric Cardiology 2022年第10期19卷 761-767页

作者： Mhd Nawar Alachkar Annemarie Kirschfink Anas Alnaimi jörg Schröder Felix Vogt nikolaus Marx Ertunc Altiok Mohammad Almalla Department of Cardiology and Angiology REGIOMED Hospital CoburgCoburgGermany Department of Cardiology Angiology and Intensive CareMedical Clinic ⅠUniversity Hospital RWTH AachenAachenGermany

OBjECTIVE To evaluate the safety and efficacy of transcatheter mitral valve repair(TMVR)using MitraClip^(■)devices in oldest-old patients compared to younger *** The study retrospectively included 340 consecutive patients who underwent *** were classified according to age into the oldest-old(age≥85 years)patient group or the younger(age<85 years)patient *** results of the procedure,intrahospital outcomes and one-year outcomes were *** Oldest-old patients represented 15.9%(n=54)of all *** success was comparable for the oldest-old patient group and the younger patient group(92.6%vs.95.8%,P=0.30),and there was no difference in intrahospital mortality(9.2%vs.4.2%,P=0.12).At a one-year follow-up(interquartile range:6–16 months),there was no significant difference in rehospitalization due to decompensated heart failure(25.5%vs.34.3%,P=0.24)or all-cause mortality(29.8%vs.22.2%,P=0.26)between the oldest-old patient group and the younger patient *** patients with available echocardiographic follow-up,severity of residual mitral regurgitation was also comparable between the oldest-old patient group and the younger patient *** TMVR seems to be feasible and effective in oldest-old patients and should be considered for oldest-old patients presenting with symptomatic severe mitral regurgitation and high surgical risk.

关键词： patients mitral mortality

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Different Responses of Sexual and Asexual Reproduction of Arundinella hirta to Flooding

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Frontiers in Biology 2006年第1期1卷 46-49页

作者： Zeng Bo Fu Tianfei Ulrich Schurr Arnd j.kuhn School of Life Science Southwest China UniversityChongqing 400715China Key Laboratory of Eco-environments in Three Gorges Reservoir Region(MOE) Southwest China UniversityChongqing 400715China Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir Region Southwest China UniversityChongqing 400715China Research Center of juelich ICG Ⅲ(Phytosphere)52425 JuelichGermany

The sexual and asexual reproductive features of the graminoid species Arundinella hirta growing at riversides of the jialing River were *** was found that the total seed mass,seed number per plant,and sexual reproductive allocation of *** decreased with decreasing bank elevation,and plants growing at the lowest elevations of banks subjected to intense flooding did not show sexual *** total plant biomass and the number of ramifications per plant increased with flooding intensity,which implies that,contrary to sexual reproduction,asexual reproduction of *** was enhanced by flooding.

关键词： Arundinella hirta asexual reproduction flooding reproductive allocation sexual reproduction

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Multi-scale drivers of soil resistance predict vulnerability of seasonally wet meadows to trampling by pack stock animals in the Sierra Nevada,USA

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Ecological Processes 2020年第1期9卷 364-377页

作者： joy S.Baccei Mitchel P.McClaran Tim j.kuhn Stephen C.Hart Environmental Systems Graduate Group University of CaliforniaMercedCA 95343USA UC Merced Vernal Pools and Grassland Reserve UC Merced Natural Reserve SystemMercedCA 95343USA School of Natural Resources and the Environment University of ArizonaTucsonAZ 85721USA Resources Management and Science Yosemite National ParkEl PortalCA 95318USA Department of Life&Environmental Sciences and Sierra Nevada Research Institute University of CaliforniaMercedCA 95343USA.

Background:Meadow ecosystems have important ecological functions and support socioeconomic services,yet are subject to multiple stressors that can lead to rapid *** the Sierra Nevada of the western USA,recreational pack stock(horses and mules)use in seasonally wet mountain meadows may lead to soil trampling and meadow degradation,especially when soil water content is high and vegetation is ***:In order to improve the ability to predict meadow vulnerability to soil disturbance from pack stock use,we measured soil resistance(SR),which is an index of vulnerability to trampling disturbance,at two spatial scales using a stratified-random sampling *** then compared SR to several soil and vegetation explanatory variables that were also measured at the two spatial scales:plant community type(local scale)and topographic gradient class(meadow scale).Results:We found that local-scale differences in drivers of SR were contingent on the meadow scale,which is important because multiple spatial scale evaluation of ecological metrics provides a broader understanding of the potential controls on ecological processes than assessments conducted at a single spatial *** also found two contrasting explanatory models for drivers of SR at the local scale:(1)soil gravimetric water content effects on soil disaggregation and(2)soil bulk density and root mass influence on soil *** resistance was insufficient to sustain pack stock use without incurring soil deformation in wet plant communities,even when plant cover was maximal during a major ***:Our study provides new information on seasonally wet meadow vulnerability to trampling by pack stock animals using multi-scale drivers of SR,including the contrasting roles of soil disaggregation,friction,and *** work aims to inform meadow management efforts in the Sierra Nevada and herbaceous ecosystems in similar regions that are subject to seasonal soil saturation and livestock u

关键词： Hydrogeomorphic classification Hydrologic regime Pack stock Plant communities Soil properties Soil strength

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Modulating effects of acyl-CoA synthetase 5-derived mitochondrial Wnt2B palmitoylation on intestinal Wnt activity

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World journal of Gastroenterology 2014年第40期20卷 14855-14864页

作者： Christina Klaus Ursula Schneider Christian Hedberg Anke K Schütz jürgen Bernhagen Herbert Waldmann nikolaus Gassler Elke Kaemmerer Institute of Pathology RWTH Aachen University 52074 Aachen Germany Department of Chemical Biology Max Planck Institute of Molecular Physiology 44227 Dortmund Germany Department of Biochemistry and Molecular Cell Biology RWTH Aachen University 52074 Aachen Germany Department of Pediatrics RWTH Aachen University 52074 Aachen Germany

AIM: To investigate the role of acyl-CoA synthetase 5 (ACSL5) activity in Wnt signaling in intestinal surface epithelia.

关键词： Acyl-CoA synthetases Wnt signaling Palmitoylation Intestinal barrier Carcinogenesis

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Clinical algorithms for the prevention of variceal bleeding and rebleeding in patients with liver cirrhosis

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World journal of Hepatology 2021年第7期13卷 731-746页

作者： nikolaus Pfisterer Lukas W Unger Thomas Reiberger Medizinische Abteilung für Gastroenterologie und Hepatologie Klinik Landstraße/Krankenanstalt RudolfstiftungVienna 1030Austria Vienna Hepatic Hemodynamic Lab Medical University of ViennaVienna 1090Austria Division of Visceral Surgery Department of General SurgeryMedical University of ViennaVienna 1090Austria Cambridge Institute of Therapeutic Immunology and Infectious Disease Jeffrey Cheah Biomedical CentreUniversity of CambridgeCambridge CB20AWUnited Kingdom Division of Gastroenterology and Hepatology Department of Medicine IIIMedical University of ViennaVienna 1090Austria Christian Doppler Laboratory for Portal Hypertension and Liver Fibrosis Medical University of ViennaVienna 1090Austria

Portal hypertension(PH),a common complication of liver cirrhosis,results in development of esophageal *** esophageal varices rupture,they cause significant upper gastrointestinal bleeding with mortality rates up to 20%despite state-of-the-art ***,prophylactic measures are of utmost importance to improve outcomes of patients with *** high-quality studies have demonstrated that non-selective beta blockers(NSBBs)or endoscopic band ligation(EBL)are effective for primary prophylaxis of variceal *** secondary prophylaxis,a combination of NSBB+EBL should be routinely *** esophageal varices develop and variceal bleeding occurs,standardized treatment algorithms should be followed to minimize bleeding-associated *** attention should be paid to avoidance of overtransfusion,early initiation of vasoconstrictive therapy,prophylactic antibiotics and early endoscopic ***-emptive transjugular intrahepatic portosystemic shunt should be used in all Child C10-C13 patients experiencing variceal bleeding,and potentially in Child B patients with active bleeding at *** use of carvedilol,safety of NSBBs in advanced cirrhosis(*** refractory ascites)and assessment of hepatic venous pressure gradient response to NSBB is *** the present review,we give an overview on the rationale behind the latest guidelines and summarize key papers that have led to significant advances in the field.

关键词： Portal hypertension Endoscopy Non-selective betablockers Transjugular intrahepatic portosystemic shunt

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Impact of Si on the high-temperature oxidation of AlCr(Si)N coatings

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journal of Materials Science & Technology 2022年第5期100卷 91-100页

作者： nikolaus jager Michael Meindlhumer Michal Zitek Stefan Spor Hynek Hruby Farwah Nahif jaakko julin Martin Rosenthal jozef Keckes Christian Mitterer Rostislav Daniel Christian Doppler Laboratory for Advanced Synthesis of Novel Multifunctional Coatings at the Department of Materials Science Montanuniversität LeobenAustria voestalpine eifeler Vacotec GmbH DüsseldorfGermany Institute of Ion Beam Physics and Materials Research Helmholtz-Zentrum Dresden-RossendorfDresdenGermany Department of Physics University of JyvaskylaFinland European Synchrotron Radiation Facility GrenobleFrance Erich Schmid Institute for Materials Science Austrian Academy of SciencesAustria Department of Materials Science Montanuniversität LeobenAustria

The resistance of wear protective coatings against oxidation is crucial for their use at high ***,three nanocomposite AlCr(Si)N coatings with a fixed Al/Cr atomic ratio of 70/30 and a varying Si-content of 0 at.%,2.5 at.% and 5 at.% were analyzed by differential scanning calorimetry,thermogravimetric analysis and X-ray in order to understand the oxidation behavior depending on their ***,a partially oxidized AlCrSiN coating with 5 at.%Si on a sapphire substrate was studied across the coating thickness by depth-resolved cross-sectional X-ray nanodiffraction and scanning trans-mission electron microscopy to investigate the elemental composition,morphology,phases and residual stress evolution of the oxide scale and the non-oxidized coating *** results reveal enhanced oxidation properties of the AlCr(Si)N coatings with increasing Si-content,as demonstrated by a retarded onset of oxidation to higher temperatures from 1100℃ for AlCrN to 1260℃ for the Si-containing coatings and a simultaneous deceleration of the oxidation *** annealing of the AlCrSiN sample with5 at.%Si at an extraordinary high temperature of 1400℃ for 60 min in ambient air,three zones developed throughout the coating strongly differing in their composition and structure:(i)a dense oxide layer comprising an Al-rich and a Cr-rich zone formed at the very top,followed by(ii)a fine-grained transition zone with incomplete oxidation and(iii)a non-oxidized zone with a porous *** varying elemental composition of these zones is furthermore accompanied by micro-structural variations and a complex residual stress development revealed by cross-sectional X-ray *** results provide a deeper understanding of the oxidation behavior of AlCr(Si)N coatings depending on their Si-content and the associated elemental,microstructural and residual stress evolution during high-temperature oxidation.

关键词： AlCrSiN Nanocomposite Cathodic arc Oxidation behaviour Cross-sectional X-ray nanodiffraction

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Effects of far-off and close-up transition cow feeding on uterine health,postpartum anestrous interval,and reproductive outcomes in pasture-based dairy cows

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journal of Animal Science and Biotechnology 2020年第2期11卷 493-503页

作者： S.Meier j.K.Kay B.kuhn-Sherlock A.Heiser M.D.Mitchell M.A.Crookenden M.Vailati Riboni j.j.Loor j.R.Roche DairyNZ Limited Private Bag 3221Hamilton 3240New Zealand AgResearch Hopkirk Research InstituteGrasslands Research CentrePalmerston North 4442New Zealand Centre for Children’s Health Research Queensland University of TechnologyLevel 662 Graham StreetSouth BrisbaneQueensland 4101Australia DairyNZ Limited c/o University of Auckland3A Symonds StAuckland 1010New Zealand Department of Animal Sciences University of IllinoisUrbana 61801USA Ministry for Primary Industries-ManatūAhu Matua Charles Ferguson TowerPipiteaWellington 6140New Zealand School of Biological Sciences University of AucklandPrivate Bag 92019Auckland 1142New Zealand

Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 *** achieve this,the uterus must involute and ovulation must occur and continue at regular *** these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive *** treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial *** randomly assigned 150 cows to one of two far-off *** late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of *** each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving ***:Uterine health improved(***(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed *** reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up *** postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed inta

关键词： Close-up Dairy cows Far-off Reproduction Transition period

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