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Catchment soils as a factor.of tr.ce metal accumulation in sediments of the r.ser.oir.Klingenber.(easter. Or. Mountains, Ger.any)

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Jour.al of Envir.nmental Sciences 2019年第12期31卷 1-14页

作者： Jens Hahn Chr.stian Opp r.phael Ganzenmuller.Anntke ewert Bir.it Schneider.Nina Zitzer.Gabr.ela Laufenber. Philipps-Univer.ity of Mar.ur. Working Group for Hydro-and Soil GeographyDeutschhausstr.1035037 MarburgGermany Univer.ity of Leipzig Institute of GeographyPhysical GeographyJohannisallee 19a04103 LeipzigGermany Philipps-Uniuer.ity o/Mar.itr. Mass SpectrometryMarbacher Weg 6-1035037 MarburgGermany

The r.lease and accumulation dynamics of tr.ce metals in soils and aquatic sediments wer. exemplar.ly investigated in the catchment ar.a of the r.ser.oir.Klingenber.(Ger.any).Catchment soils wer. examined for.mobilizable and total concentr.tions of ar.enic(As),cadmium(Cd),chr.me(Cr.,ir.n(Fe),manganese(Mn),nickel(Ni),lead(Pb),and zinc(Zn)and compar.d with tr.ce metal quantities accumulated in r.ver.ed and r.ser.oir.*** compar.son of all samples showed r.latively small var.ations of Cr.7.96–46.0 mg/kg),Fe(7.79–40.4 g/kg),and Ni(6.06–56.5 mg/kg),while str.nger.differ.nces wer. found for.As(11.2–164 mg/kg),Cd(0.14–30.5 mg/kg),Mn(0.08–1.84 g/kg),Pb(20.7–183 mg/kg),and Zn(69.1–916 mg/kg).The catchment soils wer. slightly enr.ched by Cd,Pb,and *** Cd and Zn wer. char.cter.zed by lar.e mobilizable *** mean tr.ce metal concentr.tions in r.ver.ed sediments wer. higher.than in catchment soils,while r.ser.oir.sediments accumulated the highest amounts of the analyzed *** enr.chment of tr.ce metals in r.ser.oir.sediments was gener.lly deter.ined by the sedimentation of fine par.icles,while the distr.bution of As,Fe,and Mn was additionally impacted by r.dox *** Cd and Zn,which in compar.son wer. most enr.ched in r.ver.ed and r.ser.oir.sediments,a significant r.lease fr.m soils by leaching pr.cesses was *** accumulation of As and Pb in r.ser.oir.sediments was influenced to a gr.ater.extent by soil er.sion and by anthr.pogenic or.chalcogen sour.es in the catchment.

关键词： Tr.ce metals Exchangeable for.s Soil Sediment Catchment Sour.es

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Segmentation and Tr.cking of Neur.l Stem Cell

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Chinese Jour.al of Biomedical Engineer.ng(English Edition) 2005年第3期14卷 93-103页

作者： ewert Bengtsson Infor.ation & Communication Institute Harbin Engineering UniversityHarbin 150001China

In or.er.to under.tand the development of stem cells into specialized matur. cells it is necessar. to study the gr.wth of cells in cultur.. For.this pur.ose it is ver. useful to have an efficient computer.zed cell tr.cking system. In this paper.a pr.totype system for.tr.cking neur.l stem cells in a sequence of images is descr.bed. In or.er.to get r.liable tr.cking r.sults it is impor.ant to have good and r.bust segmentation of the cells. To achieve this we have implemented thr.e levels of segmentation. The pr.mar. level, applied to all fr.mes, is based on fuzzy thr.shold and water.hed segmentation of a fuzzy gr.y weighted distance tr.nsfor.ed image. The second level, applied to difficult fr.mes wher. the fir.t algor.thm seems to have failed, is based on a fast geometr.c active contour.model based on the level set algor.thm. Finally, the automatic segmentation r.sult on the cr.cial fir.t fr.me can be inter.ctively inspected and cor.ected. Visual inspection and cor.ection can also be applied to other.fr.mes but this is gener.lly not needed. For.the tr.cking all cells ar. classified into inactive, active, dividing and cluster.d cells. Differ.nt algor.thms ar. used to deal with the differ.nt cell categor.es. A special backtr.cking step is used to automatically cor.ect for.some common er.or. that appear.in the initial for.ar. tr.cking pr.cess.

关键词： Tr.cking Stem cells Level set Time lapse image sequence

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Minor.Pr.ssur. Differ.nces within the Fontan-Anastomosis in Patients with Total Cavopulmonar. Connection by 4D-Flow Magnetic r.sonance Imaging

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Congenital Hear. Disease 2023年第4期18卷 461-474页

作者： Ner.jda Shehu Chr.stian Meier.ofer.Anja Hennemuth Mar.us Hüllebr.nd Pavlo Yevtushenko Peter.ewert Stefan Mar.inoff Heiko Ster. Depar.ment of Congenital Hear. Disease and Pediatr.c Car.iology German Heart Center MunichTechnical University of MunichMunichGermany Fr.unhofer.Institute for.Digital Medicine—MEVIS BerlinGermany Institute for.Car.iovascular.Computer.Assisted Medicine CharitéUniversitätsmedizinBerlinGermany Depar.ment of r.diology German Heart Center MunichTechnical University of MunichMunichGermany

Backgr.und: Pr.ssur. measur.ment in total cavopulmonar. connection (TCPC) patients is a domain of car.iaccatheter.zation. 4D velocity encoded car.iovascular.magnetic r.sonance (4D–flow Mr.) offer. an alter.ative for.ssessment of even minor.pr.ssur. differ.nces. The scope of this study was to measur. even minor.pr.ssur. differ.ncesin the anastomosis of TCPC patients, who ar. clinically uncompr.mised. Methods: Twenty-four.patients(median 15 year. [8;34]) with TCPC wer. studied pr.spectively by 4D-flow Mr.. Pr.ssur. differ.nces betweensuper.or.vena cava (SVC) and extr.car.iac conduit (C) to both r.ght pulmonar. ar.er. (r.A) and left pulmonar.ar.er. (LPA) wer. assessed. Small fluid obstr.ctions as vor.ices within the anastomosis wer. detected by flowpathlines fr.m 4D-flow Mr.. In two patients pr.ssur. differ.nces wer. calculated also by computational flowdynamics (CFD) as a plausibility check for.the or.er.of magnitude. r.sults: Median values of pr.ssur. differ.ncesin the anastomosis between SVC and r.A wer. 0.63 (0.21–2.1) mmHg, between C and r.A 0.67 (0.3–2.2)mmHg, between SVC and LPA 0.8 (0.3–2.4) mmHg and between C and LPA 0.7 (0.2–1.9) mmHg. Patients withpotential flow obstr.ction (stents, occluder. vor.ices) had significantly higher.gr.dients at the anastomosis (p r.ctions, although the absolute values wer. small. CFD- and measur.ment-based pr.ssur. differ.nce showed good agr.ement. Conclusion: 4D-flow Mr. is able to detect minor.pr.ssur.differ.nces within the Fontan cir.uit even in patients with appar.ntly satisfactor. TCPC. Slightly higher.r.ssur. differ.nces ar. due to the pr.sence of small flow obstr.ction.

关键词： 4D-flow Mr. pr.ssur. differ.nces TCPC Fontan

Functional attr.butes of two subtr.pical shr.bs and implications for.the distr.bution and management of endanger.d bir. habitat

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Jour.al of Plant Ecology 2015年第6期8卷 578-592页

作者： Genie M.Fleming Joseph M.Wunder.e Jr.David N.ewert Joseph J.O’Br.en Eileen H.Helmer Puer.o r.can Conser.ation Foundation PO Box 362495San JuanPR 00936USA Inter.ational Institute of Tr.pical For.str. USDA Forest ServiceSabana Field Research StationHC 02 Box 6205LuquilloPR 00773-1377USA The Natur. Conser.ancy 101 East Grand RiverLansingMI 48906USA Center.for.For.st Distur.ance Science USDA Forest Service320 Green StAthensGA 30602USA

Aims The fr.its of Er.thalis fr.ticosa *** Lantana involucr.ta *** impor.ant in the diet of u feder.lly endanger.d Kir.land’s War.ler.(Setophaga kir.landii)winter.ng in the bahamas *** two shr.bs occur.in tr.pical and subtr.pical dr. for.sts,including for.sts that have been subjected to r.cent *** their.impor.ance to the endanger.d war.ler.the distur.ance ecology of these shr.bs is poor.y *** sought to deter.ine,based on functional char.cter.stics of the plants,whether.their.pr.sence is favor.d by a par.icular.type or.r.gime of *** We used data fr.m field exper.ments(seed br.adcasting and shr.b cutting)conducted on the island of Eleuther.,The bahamas to deter.ine mechanisms of and conditions favor.ng establishment and per.istence(‘vital attr.butes’)of *** and ***,which enabled categor.zation accor.ing to the plant functional types defined by Noble and slatyer.1980).We then compar.d hypothesized distr.butions of these plant functional types among differ.nt anthr.pogenic distur.ance r.gimes to obser.ed distr.bu-tions of *** and *** in or.er.to identify distur.bance r.gimes most likely to pr.duce habitat used by Kir.land’s *** Findings *** and *** wer. functionally categor.zed as widely disper.ed but lar.ely shade intoler.nt species capable of establishing or.r.gener.ting individuals after.distur.ance via both seeds and vegetative *** hypothesized and obser.ed distr.bution patter.s indicated the shr.bs wer. favor.d by a r.gime of fr.quent distur.ance pr.ducing open canopy and gr.und *** the anthr.pogenic distur.ances we examined,ar.as of lar.e-scale land clear.ng combined with subsequent goat gr.z-ing most often suppor.ed *** and ***,while the shr.bs wer. r.latively r.r. in bur.ed *** the plant functional type fr.mewor. in combination with field data to evaluate pr.dictions of species occur

关键词： anthr.pogenic distur.ance black tor.h plant functional type vital attr.butes wild sage

Str.tegies for.Film r.placement in r.diogr.phy Films and Digital Detector. in Compar.son

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Strategies for Film Replacement in Radiography Films and Dig...

Calibr.ting volume measur.ments made using the dual-field conductance catheter

17th Wor.d Confer.nce on Non-Destr.ctive Testing

作者： Uwe ewert Uwe ZSCHEr.EL Klaus BAVENDIEK Institute for.Mater.als r.sear.h and Testing (BAM) D-12200 BerlinGermany YXLON Inter.ational GmbH D-22419 HamburgGermany

＜正＞The NDT community has discussed about effective film r.placement by Computed r.diogr.phy（Cr.and the new Digital Detector.Ar.ays（DDA）,also known as flat panel detector.,since mor. than 10 *** standar.s wer. published by CEN,ASTM and ASME to suppor. the application of phosphor.imaging plates in lieu of X-r.y film in the year.*** of the key concepts is the usage of signal/noise（SNr.measur.ments as equivalent to the optical density of film and film system *** r.diogr.phic pr.ctice with DDAs is not yet descr.bed by any standar.,but pr.posals ar. under.*** fir.t qualification standar. for.DDAs,ASTM E 2597-07,has been published r.cently. The bad pixel pr.blem has been *** methods wer. elabor.ted and tested at BAM for.deter.ination of par.meter. as basic spatial r.solution,efficiency,specific mater.al thickness r.nge,contr.st sensitivity and image *** pr.cedur.s wer. used for.this study. The achieved image quality is discussed for.film r.placement by Cr.and DDAs in weld *** str.tegies for.cor.ect DDA calibr.tion yield an extr. or.inar. incr.ase of image *** contr.st sensitivity was enhanced up to 10 times in r.lation to film *** could not yet be achieved by any other.*** r.str.ctions in the spatial r.solution,pr.voked by the individual pictur. element（pixel）size of the detector.ar. compensated by the incr.ased contr.st sensitivity.

关键词： r.diogr.phy Film r.placement Computed r.diogr.phy Imaging plates Digital detector.ar.ays Contr.st sensitivity SNr Standar.s

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Jour.al of Biomedical Science and Engineer.ng 2009年第7期2卷 484-490页

作者： Simon P. McGuir. David Bar.on Dan ewert John H. Coote 不详

The conductance catheter.technique allows r.al- time measur.ments of ventr.cular.volume based on changes in the electr.cal conductance of blood within the ventr.cular.cavity. Conductance volume measur.ments ar. cor.ected with a calibr.tion coefficient, α, in or.er.to impr.ve accur.cy. However. conductance volume measur.ments ar. also affected by par.llel conductance, which may confound cali-br.tion coefficient estimation. This study was un-der.aken to examine the var.ation in α using a physical model of the left ventr.cle without par.llel conductance. Calibr.tion coefficients wer. calculated as the conductance-volume quotient (αV(t)) or.the str.ke conductance-str.ke volume quotient (αSV). Both calibr.tion coefficients var.ed as a non-linear.function of the ventr.cular.volume. Conductance volume measur.ments calibr.ted with αV(t) estimated ventr.cular.volume to within 2.0 ±6.9%. By contr.st, calibr.tion with αSV substantially over.estimated the ventr.cular.volume in a volume-dependent manner. incr.asing fr.m 26 ±20% at 100ml to 106 ±36% at 500ml. The accur.cy of conductance volume measur.ments is affected by the choice of calibr.tion coefficient. Using a fixed or.constant calibr.tion coeffi-cient will r.sult in volume measur.ment er.or.. The conductance-str.ke volume quotient is associated with par.icular.y significant and volume-dependent measur.ment er.or.. For.this r.ason, conductance volume measur.ments should ideally be calibr.ted with an alter.ative measur.ment of ventr.cular.vol-ume.

关键词： Conductance Catheter Calibr.tion Volume Measur.ment

Electr.car.iogr.phic inter.er.nce and conductance volume measur.ments

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Jour.al of Biomedical Science and Engineer.ng 2009年第7期2卷 491-498页

作者： Simon P. McGuir. Dan ewert David J. Bar.on John H. Coote 不详

The conductance catheter.technique enables continuous ventr.cular.volume measur.ments based on the electr.cal conductance of blood within the ventr.cular.cavity. However. ventr.cular.excitation also pr.duces a measur.ble electr.cal signal within the ventr.cular.cavity. This study was under.aken to investigate the r.lationship between the ventr.cular.electr.gr.m and conductance volume measur.ments in a physical model of the left ventr.cle without par.llel conductance. The ventr.cular.electr.gr.m was simulated with an ECG signal, ECGinput connected to two r.ng electr.des within the model ventr.cle. Conductance volume measur.ments wer. made with and without ECGinput. The differ.nce between these measur.ments, GECG(t), r.pr.sented the conductance volume due to ECGinput. GECG(t) var.ed as a function of the fir.t-der.vative of ECGinput with r.spect to time (r.=0.92, Pr.mar.ly affected volume measur.ments dur.ng ventr.cular.depolar.sation;dur.ng this phase the volume measur.ment er.or.var.ed widely between –12% and +9%. As a r.-sult, end-diastole could not be r.liably identified on the pr.ssur.-volume loop. The accur.cy of conduc-tance volume measur.ments dur.ng late diastole and ear.y isovolumic contr.ction ar. substantially affected by the ventr.cular.electr.gr.m. This may r.sult in a significant er.or.in end-diastolic volume estimates, which has impor.ant implications for.the quantitative assessment of ventr.cular.function including, in par.icular. the assessment of chamber.compliance.

关键词： Volume Measur.ment Conductance Catheter Electr.car.iogr.m Ventr.cular Electr.gr.m

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卫星接收系统C向Ku波段升级的安装与调整

现代电视技术 1997年第4期 49-54,60页

作者： Jur.en ewert 陈玉生

在没有电缆电视的边远地区，卫星系统是最常用的。通常，这些系统是C波段系统。C波段频率范围是3．7GHz～4．7GHz。在C波段上安排节目可以多样化，但是，在扩展到Ku波段的情况下就可以更加多样化了。

关键词：卫星接收系统 Ku波段调整安装 C波段边远地区电缆电视卫星系统频率范围

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大坝现场不同类别岩石的注浆方法

大坝现场不同类别岩石的注浆方法