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Experimental and numerical modelling of sedimentation in a rectangular shallow basin

International Journal of Sediment Research 2008年第3期23卷 212-232页

作者： Sameh A. KANTOUSH Erik BOLLAERT anton J. SCHLEISS Ecole Polytechnique Fédérale de Lausanne (EPFL) Laboratory of Hydraulic Constructions (LCH) Station 18 CH -1015 Lausanne SwitzerlandDr. Ecole Polytechnique Fédérale de Lausanne (EPFL) Laboratory of Hydraulic Constructions (LCH) Station 18 CH -1015 Lausanne SwitzerlandProf.

Numerical simulation of flows in shallow reservoirs has to be checked for its consistency in predicting real flow conditions and sedimentation patterns. Typical flow patterns may exhibit flow separation at the inlet, accompanied by several recirculation and stagnation areas all over the reservoir surface. The aim of the present research project is to study the influence of the geometry of a reservoir on sediment transport and deposition numerically and experimentally, focusing on a prototype reservoir depth between 5 and 15 m as well as suspended sediment transport. A series of numerical simulations is presented and compared with scaled laboratory experiments, with the objective of testing the sensitivity to different flow and sediment parameters and different turbulence closure schemes. Different scenarios are analyzed and a detailed comparison of preliminary laboratory tests and some selected simulations are presented. The laboratory experiments show that suspended sediment transport and deposition are determined by the initial flow pattern and by the upstream and downstream boundary conditions. In the experiments, deposition in the rectangular basin systematically developed along the left bank, although inflow and outflow were positioned symmetrically along the centre of the basin. Three major horizontal eddies developed influencing the sediment deposition pattern. Although asymmetric flow patterns are privileged, a symmetric pattern can appear from time to time. This particular behaviour could also be reproduced by a two-dimensional depth-averaged flow and sediment transport model (CCHE2D). The paper presents numerical simulations using different turbulence closure schemes (k-ε and eddy viscosity models). In spite of the symmetric setup, these generally produced an asymmetric flow pattern that can easily switch sides depending on the assumptions made for the initial and boundary conditions. When using the laboratory experiment as a reference, the most reliable n

关键词： Shallow reservoir sedimentation and morphology Suspended sediment Reservoir geometry influence Numerical simulations Scaled physical modelling

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Influence of vascular endothelial growth factor and radiation on gap junctional intercellular communication in glioblastoma multiforme cell lines

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Neural Regeneration Research 2017年第11期12卷 1816-1822页

作者： Reinhardt Krcek Pauline Latzer Irenaus anton Adamietz Helmut Biihler Carsten Theiss Institute of Anatomy Department of CytologyRuhr-University BochumBochumNorth Rhine-WestphaliaGermany Department of Radiotherapy and Radio-Oncology University Medical Centre MarienhospitalRuhr-University BochumHerneNorth Rhine-WestphaliaGermany Institute for Molecular Oncology Radio-Biology and Experimental RadiotherapyUniversity Medical Centre MarienhospitalRuhr-University BochumHerneNorth Rhine-WestphaliaGermany

Glioblastoma multiforme （GBM） is a highly aggressive glial brain tumor with an unfavorable prognosis despite all current therapies including surgery, radiation and chemotherapy. One characteristic of this tumor is a strong synthesis of vascular endothelial growth factor （VEGF）, an angiogenesis factor, followed by pronounced vascularization. VEGF became a target in the treatment of GBM, for example with bevacizumab or the tyrosine kinase inhibitor axitinib, which blocks VEGF receptors. To improve patients＇ prognosis, new targets in the treatment of GBM are under investigations. The role of gap junctions in GBM remains un- known, but some experimental therapies affect these intercellular channels to treat the tumor. Gap junctions are composed of connexins to allow the transport of small molecules between adjacent cells through gap junc- tional intercellular communication （GJIC）. Based on data derived from astrocytes in former studies, which show that VEGF is able to enhance GJIC, the current study analyzed the effects of VEGF, radiation therapy and VEGF receptor blockade by axitinib on GJIC in human GBM cell lines U-87 and U-251. While VEGF is able to induce GJIC in U-251 cells but not in U-87 cells, radiation enhances GJIC in both cell lines. VEGF reocptor blockade by axitinib diminishes radiation induced effects in U-251 partially, while increases GJIC in U-87 cells. Our data indicate that VEGF and radiation are both modifying components of GJ1C in pathologic brain tumor tissue.

关键词： cell communication vascular endothelial growth factor irradiation vascular endothelial growth factor-receptor blockade glioma neurobiotin connexin cell culture immunohistochemistry microinjection

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Managing reservoir sedimentation by venting turbidity currents:A review

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International Journal of Sediment Research 2016年第3期31卷 195-204页

作者： Sabine Chamoun Giovanni De Cesare anton J.Schleiss Laboratory of Hydraulic Constructions(LCH) Swiss Federal Institute of Technology Lausanne(EPFL)

Reservoir sedimentation is an issue that dam operators are increasingly facing as dams are *** only does it reduce a reservoir's capacity but it also affects its outlet structures such as bottom outlets and powerhouse *** may also impoverish downstream *** these reasons,several strategies for sediment management are being investigated and applied *** these methods,venting of turbidity currents reaching the dam can be very beneficial and *** measure helps in preserving a certain continuity of sediment transport in rivers obstructed by ***,several practical but also theoretical challenges hamper this technique,rendering its use less common and its aspects relatively *** present paper aims to gather the actual state-of-the-art concerning turbidity currents venting and to present an outlook for future development and research in this field.

关键词： Reservoir management Sedimentation Turbidity current Venting efficiency Bottom outlet

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Directional changes of species spatial dispersion and realized environmental niches drive plant community assembly during early plant succession

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Journal of Plant Ecology 2019年第3期12卷 409-418页

作者： Werner Ulrich Markus Klemens Zaplata Susanne Winter anton Fischer Department of Ecology and Biogeography Nicolaus Copernicus University in TorunLwowska 1PL 87-100 ToruńPoland Hydrology and Water Resources Management Brandenburg University of Technology Cottbus-SenftenbergSiemens-Halske-Ring 10D-03046 CottbusGermany Faculty of Forest and Environment Section of Applied Ecology and ZoologyEberswalde University of Sustainable DevelopmentAlfred-Möller-Str.5D-16225 EberswaldeGermany Department of Geobotany Center of Life and Food SciencesTechnische Universität MünchenHans-Carl-von-Carlowitz-Platz 2D-85354 FreisingGermany

Aims Probabilistic models of species co-occurrences predict aggre-gated intraspecific spatial distributions that might decrease the degree of joint species occurrences and increase community ***,little is known about the influence of intraspecific aggre-gation on the co-occurrence of species in natural,species-rich ***,we focus on early plant succession and ask how changes in intraspecific aggregation of colonizing plant spe-cies influence the pattern of species co-existence,richness and *** We studied the early vegetation succession in a six ha constructed catchment within the abandoned part of a lignite mine in NE *** two spatial scales(1-and 25-m2 plots),we compared for each pair of species the intraspecific degree of aggregation and the pattern of co-occurrence and compared observed rela-tionships with temporal changes in important species functional *** Findings The majority of species occurred in an aggregated manner,particu-larly in the first 2 years of *** pairwise comparisons,we found an excess of segregated species occurrences leading to a posi-tive link between intraspecific aggregation and pairwise species seg-regation as predicted by the aggregation hypothesis,particularly at the lower spatial *** degree of intraspecific aggregation was negatively correlated with the community-wide level of species spatial turnover and with plot species *** results are the first direct confirmation that increasing intraspecific aggregation and interspecific competitive interactions counteract in shaping plant community structure during *** respective effects of aggregation were strongest at intermediate states of early succession.

关键词： primary succession spatial analysis environmental niche functional traits species aggregation

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Unrecognized diversity in New Guinean crayfish species (Decapoda, Parastacidae): The evidence from molecular data

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Integrative Zoology 2016年第6期11卷 457-468页

作者： Martin BLÁHA Jiří PATOKA Pavel KOZÁK antonín KOUBA Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of HydrocenosesUniversity of South Bohemia inČeskéBudějoviceVodňanyCzech Republic Department of Zoology and Fisheries Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences PraguePrahaCzech Republic

The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes(COI,16S and 12S)and by comparison with available GenBank sequences of 14 Cherax ***,the concordance of previously described species obtained from a wholesaler(Cherax boesemani,*** and ***)with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax ***cently described species ***,*** and *** belong to the northern group of Cherax *** and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species,suggesting 5 putative new ***,species assigned to the subgenus Astaconephrops do not form a monophyletic clade;this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male *** importation of crayfish underscores the importance of accurate species *** of basic molecular methods is a necessary requisite for documenting occurrence,abundance and population trends of target ***,it helps to support eventual conservation decision-making by stakeholders.

关键词： Cherax cytochrome c oxidase DNA barcoding mitochondrial DNA ornamental crayfish

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Struvite Recovery from Swine Waste Biogas Digester Effluent through a Stainless Steel Device under Constant pH Conditions

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Biomedical and Environmental Sciences 2009年第3期22卷 201-209页

作者： P.W.anton PERERA College of Environmental and Resource Sciences Zhejiang University

Objective To investigate the struvite precipitation under constant and non-constant pH conditions and to test a stainless steel device under different operating regimes to maximize the recovery of struvite. Methods The molar ratio of NH4^＋： Mg^2＋ PO43 was adjusted to 1： 1.2：1.2 and pH was elevated to 9.0. The absorbance measurement was used to trace the process of struvite crystallization. Wastewater and precipitate analysis was done by standard analytical methods. Results The pH constant experiment reported a significantly higher struvite precipitation （24.6±0.86 g） than the non-constant pH experiment （19.8±1.86 g）. The SAR ranged from 5.6 to 8.2 g m^-2h^-1 to 3.6-4.8 g m^-2h^-1 in pH constant and non-constant experiments, respectively. The highest struvite deposit on the device was found in regime 3 followed by in regimes 2 and 4. The highest PO4^3- （97.2%） and NH4^＋（71%） removal was reported in the R1 regime. None of the influent Cu^2＋ or Zn^2＋ was precipitated on the device. Conclusion A higher struvite yield is evident in pH constant experiments. Moreover, the stainless steel device facilitates the isolation of heavy metal free pure （around 96%） struvite from swine waste biogas digester effluent contaminated with Cu^2＋ and Zn^2＋ and the highest yield is attainable with the device operating at 50 rpm with agitation by a magnetic stirrer.

关键词： Struvite recovery Accumulation device Swine waste Constant pH Struvite precipitation

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Non Operative Treatments for Cervical Syndrome (Nerve Root Type)

Non Operative Treatments for Cervical Syndrome (Nerve Root T...

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作者： anton Junardi（邓汉华）重庆医科大学

学位级别：硕士

Cervical syndrome is a common disease that attack 30-60 years old patients. This disease usually recurrent and has close relationship with habit, trauma and occupation. The goals of treatment will be to provide pain relief, to improve range of neck movement, and to prevent long-term disability [1]. Acupuncture has a long history in managing cervical syndrome with good result and a little side effect. Objective: To get clinical practices and experiences of acupuncture and Chinese massage skills as part of comprehensive treatments （Western medicine and Traditional Chinese Medicine） to manage patients with cervical syndrome （nerve root type） Methods: In this paper are presented two case reports of patient with cervical syndrome （nerve root type） that clearly show in history, physical examination and radiologic findings. This two patients are treated with electro-acupuncture as a part of comprehensive treatments and other treatments also been given （Chinese massage, traction, mid-current frequency treatment）. Tools : 1. disposable filiform needles （Hwato product）, length 25 mm , diameter 0.30 mm;2. electro-acupuncture device （Hwato SDZ-II）;3. TDP. Acupoints selected [2,3] : 1. Main acupoints : Cervical level Hua Tou Jia Ji （EX B2）, Fengchi （GB 20）, Dazhui （GV 14） and Ashi acupoints;2. Additional acupoints : For exogenous wind-cold attack : Hegu （LI 4）, Waiguan （TE 5）, Fengmen （BL 12） and Jianjing（GB21） area added;for stagnation of qi and blood, Hegu （LI 4）, Quchi （LI 11）, Jianyu （LI 15）, Geshu （BL 17） and Yanglingquan （GB 34） area added;for insufficiency of liver and kidney, Ganshu （BL 18）, Shenshu （BL 23）, Zusanli （ST 36）, Xuanzhong （GB 39） and Taichong （LR 3） are added. Performance : 1. patients in prone position, 2. sterilized skin in area which needle will be inserted, 3. select acupoints based on patient complain and condition, 4. after the needle inserted, manipulating the needle with twirling-rotating and lifting-thrusting until the arrival of

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Remote sensing ***-based monitoring of agricultural terrace degradation

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International Soil and Water Conservation Research 2021年第1期9卷 1-10页

作者： anton Pijl Edoardo Quarella Teun A.Vogel Vincenzo D'Agostino Paolo Tarolli Dept.of Land EnvironmentAgriculture and ForestryUniversity of PadovaVialedell'Università1635020LegnaroPDItaly Soil Physics and Land Management Group Wageningen UniversityDroevendaalsesteeg 46708PBWageningenthe Netherlands

The degradation of agricultural terraces is considered a major challenge to soil and water conservation in steep-slope *** terracing is a widespread conservation practice,its sustainability is threatened by adverse climatic and man-made *** studies have shown the impact of terrace designs on the formation of runoff pathways,causing degradation processes on terrace platforms(*** erosion)and walls(***,landslides,collapse).This study evaluates a remote sensing versus a field-based approach to monitor hydrological processes responsible for terrace degradation,as tested in a north-Italian *** field-based approach was based on spatially measured Soil Moisture Content(SMC)using a Time Domain Reflectometry(TDR)instrument,which clearly revealed saturation hotspots around two damaged terraces in the study ***,these zones showed a particular cross-sectional SMC profile,with the highest saturation close to the terrace platform *** remote sensing approach was based on aerial imagery acquired by an Unmanned Aerial Vehicle(UAV)and photogrammetric reconstruction of the vineyard geomorphology,allowing terrain-based analysis and physical erosion *** this approach,simulations indicated that terrace damages could be partly explained by the formation of preferential runoff pathways caused by the terrace *** parallel methodology allowed a comparison of the merits and limitations of either approach,as done in light of published *** occurrence of two SMC hotspots at terrace edges(and their non-typical cross-sectional profiles)could be better understood from simulated surface flow *** the causal relationship between heterogeneous soil saturation and terrace instability has been previously reported in literature,the novelty of the presented study is the use of topsoil SMC as an indicator of potential damages,favouring the scalability compared to fixed,local and often intrusive terrace sub-sur

关键词： Agricultural terraces Remote sensing UAV Soil moisture Land degradation

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Sr-Isotopic Characteristic of the Typical Carbonate Neoproterozoic Siberia Sections

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地学前缘 2009年第S1期16卷 194-195页

作者： Vishnevskaya Irine Kuznetsov anton Letnikova Elena Institute of Geology and Mineralogy SB RAS Institute of Precambrian Geology and Geochronology RAS

First Sr isotopic data for the type of Neoproterozoic carbonate sediments of the South Siberia are reported. Upper Riphean complex is represented by terrigenous -carbonate rocks of Tungysic Formation,Yenisey Mountain *** age of this Formation shows a wide range,from 924±40 Ma(K-Ar method)to 753±6 Ma(U-Pb method).Sediments of Zabit Formation,Bokson Series(East Sayan)and

关键词： Neoproterozoic carbonate sediments Sr isotopic chemostratigraphy

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Experiments on the effect of inflow and outflow sequences on suspended sediment exchange rates

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International Journal of Sediment Research 2017年第2期32卷 155-170页

作者： Michael Müller Giovanni De Cesare anton J.Schleiss IUB Engineering Ltd

In laboratory experiments,the influence of inflow and outflow sequences on the behavior of fine sediment was *** experimental set-up consisted of two interconnected rectangular basins,between which water was moved back and *** sediment concentration in the main basin as well as the sediment exchange rates were derived from turbidity *** suspended sediment ratio,SSR,and sediment exchange rates(influx sediment rate,ISR,and evacuated sediment rate,ESR) were *** twenty test runs,a parametric study on the magnitude and frequency of inflow and outflow cycles,the relative duration between inflow and outflow sequences,the initial sediment concentration,and the intake position was *** initial test with stagnant water described the settling behavior of fine sediment and served as a reference *** test results show that settling of fine particles near the intake/outlet structure can be considerably reduced by the nature of the inflow and outflow *** cycle magnitude and frequency lead to maximum suspended sediment ratio in the *** low discharges,the evolution of suspended sediment concentration cannot be directly correlated to the inflow and outflow ***,compared to "no operation" conditions,the suspended sediment ratio could be increased by 10% to 40%*** high discharge,the evolution of suspended sediment concentration correlated with discharge cycles and suspended sediment ratios between 50% and 80%higher than for stagnant water could be *** ratios could be obtained when the intake is located closer to the bottom or to the free water ***,the overall sediment balance remained in equilibrium over the test period,indicating that the influx and evacuated sediment rates are not significantly influenced by the inflow and outflow cycles.

关键词： Laboratory experiments Inflow and outflow sequences Suspended sediment Sediment exchange rates Turbidity measurements

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