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Journal of Mountain Science 2017年第8期14卷 1513-1525页

作者： WIEDENMANN johannes ROHN Joachim MOSER Michael GeoZentrum Nordbayern Department of Applied GeologyUniversity of Erlangen-Nürnberg

The use of LIDAR-derived shaded relief maps led to the identification of all potential landslide areas in a hilly region in Northern Bavaria(1590 km^2), Germany. Every possible structure was investigated by field investigation which resulted in a detailed database of 1002 landslides within the study area. The analysis of geological, lithological, topographical and morphological properties(spatial ratio, lithological and geological setting, length/width distribution, material properties and slope angle) revealed characteristic appearances of the landslides and possible relationships between different aspects. Strong relations between the lithological setting, spatial ratio of the mapped landslides and distribution of slope angle could be observed. This study shows the value of high-resolution shaded relief maps for detecting and mapping landslides in a large area with comparatively little work and time in comparison to the traditional approach to mapping. It reveals that many landslides were not known before. Landslides are much more common in Northern Bavaria and have a higher influence on the denudation rate of the franconian Alb than expected before.

关键词： Landslides LIDAR Appearance Spatialratio Material properties Bavaria

Assessment of agri-spillways as a soil erosion protection measure in Mediterranean sloping vineyards

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Journal of Mountain Science 2017年第6期14卷 1009-1022页

作者： Jesus RODRIGO-cOMINO Stefan WIRTZ Eric c. BREVIK Jose D.RUIZ-SINOGA johannes B.BIES Instituto de Geomorfologfa y Suelos Department of Geography University of Malaga 29071 Malaga Spain Physical Geography Trier University 542-85 Trier Germany Department of Natural Sciences 291 Campus Drive Dickinson State University Dickinson ND 58601 USA

Suitable vineyard soils enhance soil stability and biodiversity which in turn protects roots against erosion and nutrient losses. There is a lack of information related to inexpensive and suitable methods and tools to protect the soil in Mediterranean sloping vineyards(>25° of slope inclination). In the vineyards of the Montes de Málaga(southern Spain), a sustainable land management practice that controls soil erosion is actually achieved by tilling rills in the down-slope direction to canalize water and sediments. Because of their design and use, we call them agri-spillways. In this research, we assessed two agri-spillways(between 10 m and 15 m length, and slopes between 25.8° and 35°) by performing runoff experiments under extreme conditions(a motor driven pump that discharged water flows up to 1.33 l s^(-1) for 12 to 15 minutes: ≈1000 l). The final results showed: i) a great capacity by these rills to canalize large amounts of water and sediments; and, ii) higher water flow speeds(between 0.16 m s-1 and 0.28 m s^(-1)) and sediment concentrationrates(up to 1538.6 g l^(-1)) than typically found in other Mediterranean areas and land uses(such as badlands, rangelands or extensive crops of olives and almonds). The speed of water flow and the sediment concentration were much higher in the shorter and steeper rill. We concluded that agri-spillways, given correct planning and maintenance, can be a potential solution as an inexpensive method to protect the soil in sloping Mediterranean vineyards.

关键词： Agri-spillway Vineyards Runoff experiment Soil erosion Water discharge

Disruption of colonic barrier function and induction of mediator release by strains of campylobacter jejuni that invade epithelial cells

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World Journal of Gastroenterology 2008年第48期14卷 7345-7352页

作者： johannes Beltinger Jo del Buono Maeve M Skelly John Thornley Robin c Spiller William A Stack christopher J Hawkey Wolfson Digestive Diseases centre Nottingham University Hospital QMC Campus

AIM: To study the mechanisms by which campylobacter jejuni (c. jejuni) causes inflammation and diarrhea. In particular, direct interactions with intestinal epithelial cells and effects on barrier function are poorly under- stood. METHODS: To model the initial pathogenic effects of c. jejuni on intestinal epithelium, polarized human colonic HcA-7 monolayers were grown on permeabilized filters and infected apically with clinical isolates of c. jejuni. Integrity of the monolayer was monitored by changes in monolayer resistance, release of lactate dehydrogenase, mannitol fluxes and electron microscopy. Invasion of HcA-7 cells was assessed by a modified gentamicin protection assay, translocation by counting colony forming units in the basal chamber, stimulation of mediator release by immunoassays and secretory responses in monolayers stimulated by bradykinin in an Ussing chamber. RESULTS: All strains translocated across monolayers but only a minority invaded HcA-7 cells. Strains that invaded HcA-7 cells destroyed monolayer resistance over 6 h, accompanied by increased release of lactate dehydrogenase, a four-fold increase in permeability to [3H] mannitol, and ultrastructural disruption of tight junctions, with rounding and lifting of cells off the filter membrane. Synthesis of interleukin (IL)-8 and prostaglandin E2 was increased with strains that invaded the monolayer but not with those that did not. cONcLUSION: These data demonstrate two distinct effects of c. jejuni on colonic epithelial cells and provide an informative model for further investigation of initial host cell responses to c. jejuni.

关键词： campylobacter jejuni cell invasion cellculture chloride secretion colonocyte HcA-7 cells Membrane permeability Monolayer Mucosal barrier Ussing chamber

computational design of bimetallic core-shell nanoparticles for hot-carrier photocatalysis

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npj computational Materials 2018年第1期4卷 389-395页

作者： Luigi Ranno Stefano Dal forno johannes Lischner Department of Materials Imperial College LondonLondon SW72AZUK Department of Physics Imperial College LondonLondon SW72AZUK Department of Physics and Department of Materials and the Thomas Young Centre for Theory and Simulation of MaterialsImperial College LondonLondon SW72AZUK

computational design can accelerate the discovery of new materials with tailored properties,but applying this approach to plasmonic nanoparticles with diameters larger than a few nanometers is challenging as atomistic first-principles calculations are not feasible for such *** this paper,we employ a recently developed material-specific approach that combines effective mass theory for electrons with a quasistatic description of the localized surface plasmon to identify promising bimetallic core-shell nanoparticles for hot-electron ***,we calculate hot-carrier generation rates of 100 different core-shell nanoparticles and find that systems with an alkali-metal core and a transition-metal shell exhibit high figures of merit for water splitting and are stable in aqueous *** analysis reveals that the high efficiency of these systems is related to their electronic structure,which features a two-dimensional electron gas in the *** calculations further demonstrate that hotcarrier properties are highly tunable and depend sensitively on core and shell *** design rules resulting from our work can guide experimental progress towards improved solar energy conversion devices.

关键词： applying alkali diameters

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交叉层积木数值模拟研究以及连接损伤分析

工程科学学报 2016年第1期38卷 149-157页

作者：沈银澜牟在根 johannes Schneider Siegfried f.Stiemer 北京科技大学土木与环境工程学院北京100083 中国电子工程设计院北京100142 英属哥伦比亚大学应用学院土木工程系

木建筑由于结构冗余性以及钉接节点超强的吸能耗能能力在抗震中表现良好.交叉层积木是一种新型的建筑材料.本文以交叉层积木3种柔性连接试验为基础,采用Open Sees中Pinching4自定义模型模拟连接滞回曲线的高度非线性、强度退化、刚度退... 详细信息

木建筑由于结构冗余性以及钉接节点超强的吸能耗能能力在抗震中表现良好.交叉层积木是一种新型的建筑材料.本文以交叉层积木3种柔性连接试验为基础,采用Open Sees中Pinching4自定义模型模拟连接滞回曲线的高度非线性、强度退化、刚度退化和捏拢现象.基于主次半循环累积能量的损伤模型,对交叉层积木连接进行损伤分析,并提出该连接的5种性能水平的损伤指数.Pinching4模型与连接试验结果吻合较好,进一步证明该模型模拟木节点连接性能的可行性和有效性.损伤因子对应的损伤程度基本符合试验规律,其平均值在合理范围内,计算结果离散性较低.

关键词：交叉层积木结构连接数值研究损伤分析损伤累积模型

Semi-stable Extensions Over 1-dimensional Bases

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Acta Mathematica Sinica,English Series 2018年第1期34卷 103-113页

作者： Janos KOLLAR johannes NIcAISE chen Yang XU Department of Mathematics Princeton University Department of Mathematics Imperial CollegeSouth Kensington Campus Beijing International center of Mathematics Research

Given a family of calabi-Yau varieties over the punctured disc or over the field of Laurentseries, we show that, after a finite base change, the family can be extended across the origin while keeping the canonical class trivial. More generally, we prove similar extension results for families whose log-canonical class is semi-ample. We use these to show that the Berkovich and essential skeleta agree for smooth varieties over c（（t）） with semi-ample canonical class.

关键词： Semi-stable extension Laurent series essential skeleton

新型木建筑材料——交叉层积木介绍及其连接的试验研究

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工程科学学报 2015年第11期37卷 1504-1512页

作者：沈银澜牟在根 johannes Schneider Siegfried f.Stiemer 北京科技大学土木与环境工程学院北京100083 中国电子工程设计院北京100840 英属哥伦比亚大学应用学院土木工程系

交叉层积木作为一种新型木建筑材料已经在北美地区推广开来,然而在我国还没有得到引进和推广.本文介绍了这种新型材料的性能特点,总结其生产工艺、设计方法和研究进展,重点对交叉层积木七种半刚性连接的抗震性能进行试验研究.研究表明:... 详细信息

交叉层积木作为一种新型木建筑材料已经在北美地区推广开来,然而在我国还没有得到引进和推广.本文介绍了这种新型材料的性能特点,总结其生产工艺、设计方法和研究进展,重点对交叉层积木七种半刚性连接的抗震性能进行试验研究.研究表明:紧固件全部被拔出的失效模式为理想的延性破坏模式,滞回曲线表现出高度非线性、刚度退化、强度退化以及捏拢现象.通过试验数据分析,给出了在延性和承载能力两方面最佳的连接.

关键词：层积木结构生产工艺设计方法连接抗震性能破坏模式

Hepatitis c-committing the world to an eradication of the infection

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Hepatobiliary Surgery and Nutrition 2021年第1期10卷 96-99页

作者： johannes Wiegand Thomas Berg Klinik für Onkologie GastroenterologieHepatologiePneumologie und InfektiologieBereich HepatologieLeipzigGermany

In a current issue of The Lancet,Spearman and colleagues have provided an extensive global review on hepatitis c virus(HcV)infection,which covers important aspects of epidemiology,natural history,key populations at ri... 详细信息

关键词： infection epidemiology linkage

Multi-stemming strategies of Quercus glauca in an evergreen broad-leaved forest: when and where

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Journal of Plant Ecology 2020年第6期13卷 738-743页

作者： Mide Rao Duo Ye Jianhua chen Jian Ni Xiangcheng Mi Mingjian Yu Keping Ma johannes H.c.cornelissen college of chemistry and Life Sciences Zhejiang Normal UniversityJinhua 321004China Department of Ecological Science Faculty of ScienceVrije Universiteit AmsterdamDe Boelelaan 10851081 HV AmsterdamThe Netherlands State Key Laboratory of Vegetation and Environmental change Institute of BotanyChinese Academy of SciencesBeijing 100093China college of Life Sciences Zhejiang UniversityHangzhou 310058China

Aims Multi-stemming supports plants’resilience to disturbances and then contributes to soil stabilization and forest function,especially in mountain *** questions remain about(i)the ontogenetic phase at which multiple stems can occur,(ii)how habitat drivers affect multi-stemming and(iii)whether ontogenetic phase and habitat drivers *** asked these questions for Quercus glauca(ring-cupped oak),the dominant species and sprouter across large warm-temperate areas of Asia;its multi-stemmed trees reflect individual survival,population regeneration and forest ecosystem *** In a 5-ha permanent plot of subtropical evergreen broad-leaved forest in eastern china,we examined the temporal patterns and spatial distribution of multi-stemmed trees of *** within 99 quadrats of 20 m×20 *** findings There were three temporal modes for multi-stemming among the *** trees and most of them appeared to produce multiple stems from an early *** disturbances related to slope convexity appear to be the main drivers of multi-stemming of ***,the closer to the ridge,the earlier the multi-stemming ***,also for other woody species in other forests and climate zones,ontogeny and environmental drivers promoting disturbance(not only geomorphology,but also extreme weather events,soil drought,fire),as well as soil fertility,need to be considered in combination to better understand multi-stemming and its consequences for community structure.

关键词： life history strategy multi-stemmed trees ontogenetic phase persistence Quercus glauca topography

Self-templated covalent functionalization of graphitic surfaces with a quasi-periodic pattern

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Aggregate 2022年第4期3卷 121-130页

作者： Yuanzhi Xia johannes Seibel Steven De feyter Division of Molecular Imaging and Photonics Department of ChemistryKU LeuvenLeuvenBelgium

Patterned covalent functionalization of graphitic surfaces(GSs)is of interest in the development of devices and nanocomposite *** contrast to the strategies using external templates or control for realizing patterned covalent functionalization of GSs,here,we present a self-templated strategy by exploiting the synergistic effects of chemical and physical functionalization of ***,a diazonium salt is reduced by potassium iodide(KI)in dimethyl sulfoxide while the solution is in contact with a GS,resulting in its spatially heterogeneous,that is,chemical and physical,*** heterogeneous functionalization leads to a quasiperiodic pattern of striped corrals with three equivalent orientations in the covalent *** formation of the striped corrals is ascribed to physisorbed domains formed by self-assembled N_(2),which is produced in situ during the reduction of the diazonium salt,preventing the covalent functionalization.

关键词： diazonium chemistry graphitic surfaces patterned covalent functionalization quasi-periodic patterning self-templated strategy