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fISH ASSEMBLAGE RESPONSES TO DIffERENT SEcONDARY cHANNEL DESIGNS IN THE LOWER MISSISSIPPI RIVER,U.S.A.:A TEMPLATE fOR RIVER RESTORATION

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水生生物学报 2018年第6期42卷 1089-1106页

作者： KAISER Joseph E. smith shannon c.f. ScHRAMM Jr.,HAROLD L. EGGLETON Michael A. Department of Aquaculture and fisheries University of Arkansas at Pine Bluff1200 N.UniversityMail Slot 4912Pine BluffArkansas 71601U.S.A U.S.Geological Survey Mississippi Cooperative Fish and Wildlife Research UnitMississippi State University

The lower Mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Louisiana-Mississippi, U.S.A.) upstream to rkm 1504(Missouri-Kentucky, U.S.A.). four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent seconda

关键词： Mississippi River Secondary channels Dikes fish assemblages River restoration River rehabilitation

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Multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.smith Jessica L.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). Patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

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comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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Ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.Eggleton cody J.Salzmann Joseph E.Kaiser shannon c.f.smith Department of Aquaculture and fisheries University of Arkansas at Pine Bluff Arkansas Game and fish commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P carp period as reflected by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species fish assemblage Oxbow lake Large river

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DYNAMIc cOMPAcTION Of PURE cOPPER POWDER USING PULSED MAGNETIc.f.RcE

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 277-283页

作者： H.P. Yu c.f. Li National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China

The compaction of pure cu powder was carried out through a series of experiments using dynamic magnetic pulse compaction, and the effects of process parameters, such as discharge energy and compacting direction, on the homogeneity and the compaction density of compacted specimens were presented and discussed. The results indicated that the compaction density of specimens increased with the augment of discharge voltage and time. During unidirectional compaction, there was a density gradient along the loading direction in the compacted specimen, and the minimum compaction density was localized to the center of the bottom of the specimen. The larger the aspect ratio of a powder body, the higher the compaction density of the compacted specimen. And high conductivity drivers were beneficial to the increase of the compaction density. The iterative and the double direction compaction were efficient means to manufacture the homogeneous and high-density powder parts.

关键词： magnetic pulse compaction copper powder compaction density electromagnetic.f.rming

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Response of an old landslide to reservoir filling: A case history

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Science china(Technological Sciences) 2005年第Z1期48卷 27-32页

作者： L.G. Tham c.f. Lee Department of civil Engineering University of Hong Kong Hong Kong China

Unfavorable hydrodynamic evolution is considered as the major cause leading to reservoir slope instability and is often modeled by numerical method. However, this simulation is seldom checked by systematic.f.eld instrumentation. Taking the opportunity of filling the Three Gorges Reservoir, a system was established in Xietan landslide to monitor reservoir water level, subground water level, seepage pressure, rainfall and deformation, etc. The monitored data during reservoir filling shows that: (1) The water level rise in the bank lags behind the reservoir filling and the lag time depends on the bank permeability; (2) rainfall-induced subground water rise and its lag time is closely correlated to hourly rainfall, indicating that it is not feasible or sufficient to use daily rainfall for analysis; (3) the effect of inverse seepage during reservoir filling on stability is ephemeral and reservoir filling is the major cause leading to bank instability.

关键词： reservoir filling, old landslide, monitoring system, water level, deformation.

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Application and reliability analysis of DPM system in site investigation of HK weathered granite

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Journal of University of Science and Technology Beijing 2005年第6期12卷 481-488页

作者： Zhuoying Tan Meifeng cai Zhongqi Yue L.G. Tham c.f. Lee State Key Laboratory of High-Efficient Mining and Safety of Metal Mines （University of Science and Technology Beijing） Ministry of Education Beijing 100083 China Department of civil Engineering University of Hong Kong Pokfulam Road Hong Kong China

A drilling process monitor （DPM） for ground characterization of weathered granite is presented. The monitor is portable and can be mounted on a hydraulic rotary drilling rig to record various drilling parameters in real time during normal subsurface investigation. The identification method for dominative and subsidiary interfaces has been established. The study reveals that the monitored drilling parameters are dependent on geotechnical materials and can be further applied to characterize ground interfaces. The t-test between manual logging and DPM logging has been carried out. The results show that the DPM has high accuracy in interfaces detection and well agreement with the manual logging. The findings show that the device and data analysis method are of potential application in subsurface drilling exploration in weathered granites. It also seems to have prospective uses in the determination of orebody boundary as well as in the detection of geohazards.

关键词： drilling process monitoring hydraulic rotary drill instrumented borehole drilling geotechnical engineering weathered granite

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Reconstruction of lithofacies using a supervised Self-Organizing Map:Application in pseudo-wells based on a synthetic geologic cross-section

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Artificial Intelligence in Geosciences 2024年第1期5卷 14-26页

作者： carreira V.R. Bijani R. Ponte-Neto c.f. Departamento de Geologia e Geofísica Universidade Federal Fluminense(UFF)NiteróiBrazil coordenação de Geofísica Observatório Nacional(ON-MCTIC)Rio de JaneiroBrazil

Recently,machine learning(ML)has been considered a powerful technological element of different society *** transform the computer into a decision maker,several sophisticated methods and algorithms are constantly created and *** geophysics,both supervised and unsupervised ML methods have dramatically contributed to the development of seismic and well-log data *** well-logging,ML algorithms are well-suited for lithologic reconstruction problems,once there is no analytical expressions for computing well-log data produced by a particular rock ***,supervised ML methods are strongly dependent on a accurate-labeled training data-set,which is not a simple task to achieve,due to data absences or *** an adequate supervision is performed,the classification outputs tend to be more accurate than unsupervised *** work presents a supervised version of a Self-Organizing Map,named as SSOM,to solve a lithologic reconstruction problem from well-log ***,we go for a more controlled problem and simulate well-log data directly from an interpreted geologic *** then define two spec.f.c training data-sets composed by density(RHOB),sonic(DT),spontaneous potential(SP)and gamma-ray(GR)logs,all simulated through a Gaussian distribution function per *** the training data-set is created,we simulate a particular pseudo-well,referred to as classification well,for defining controlled *** one comprises a training data-set with no labeled log data of the simulated fault *** the second test,we intentionally improve the training data-set with the *** bespeak the obtained results for each test,we analyze confusion matrices,logplots,accuracy and *** from very thin layer misclassifications,the SSOM provides reasonable lithologic reconstructions,especially when the improved training data-set is considered for *** set of numerical experiments shows that our SSOM is extremely

关键词： Self-Organizing Maps Supervised machine learning Synthetic well-log data classification of lithofacies

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Instrumented borehole drilling for interface identification in intricate weathered granite ground engineering

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Journal of University of Science and Technology Beijing 2007年第3期14卷 195-199页

作者： Zhuoying Tan Meifeng cai Z.Q. Yue L.G Tham c.f. Lee State Key Laboratory for High-Efficient Mining and Safety of Metal Mines （University of Science and Technology Beijing） Ministry of Education Beijing 100083. China civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China Department of civil Engineering The University of Hong Kong Hong Kong China

The successful application in drilling for HK simple weathered granite foundation has revealed its further use in instru- mented drilling system as a ground investigation tool in the detection of other lithology formations, geohazards, underground water, and boundary of orebody. To expand the further use and test the accuracy in identification of formation, an R-20 rotary-hydraulic drill rig was instrumented with a digital drilling process monitoring system （DPM） for drilling in an intricate decomposed granite site. In this test ground, the boreholes revealed that the weathered granite alternately changes between moderate and strong. The qualitative and quantitative analysis of the penetrating parameters, indicates the effective thrust force, rotary speed, flushing pressure, penetrating rate, and displacement of the bit fluctuate at ground interfaces. It shows that the parameters get a good response with the change of rock strength at the interfaces, which can reveal the change of the intricate granite formation. Besides, a variable-slope method has been established, for identification of dominative and subsidiary interfaces in the granite site. The result from a t-test shows that the confi- dence of the instrumented drilling system in identification of the geotechnical interfaces is up to 99%.

关键词： drilling process monitoring rotary-hydraulic drilling intricate weathered granite foundation

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BESⅢ上双光子物理分析（英文）

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中国科学技术大学学报 2016年第6期46卷 449-455页

作者： REDMER c.f. 约翰内斯堡大学德国美因茨55128

BESⅢ合作组最近开始双光子物理研究,主要源于强子light-by-light散射对缪子反常磁矩的贡献有很大不确定性,电磁跃迁形状因子作为实验输入是改善计算精度的需要。在BESⅢ探测器上获得的质心能量3.77 Ge V到4.6Ge V的数据使得我们能够测... 详细信息

BESⅢ合作组最近开始双光子物理研究,主要源于强子light-by-light散射对缪子反常磁矩的贡献有很大不确定性,电磁跃迁形状因子作为实验输入是改善计算精度的需要。在BESⅢ探测器上获得的质心能量3.77 Ge V到4.6Ge V的数据使得我们能够测量轻赝标量介子的跃迁形状因子。在动量转移低于2(Ge V/c)2时单标记技术测量的结果达到前所未有的精确,该区域对于αμ的计算十分重要,并且也首次开始了π介子跃迁形状因子的双标记测量。这是π~0跃迁形状因子模型无关参数化研究的第一步。另外,多介子末态测量也在进行中.

关键词：缪子反常磁矩强light-by-light散射赝标介子跃迁形状因子单标记测量

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EffEcT Of Zr ADDITION TO Ti-KILLED STEEL ON INcLUSION fORMATION AND MIcROSTRUcTURAL EVOLUTION IN WELDING INDUcED cOARSE-GRAINED HEAT AffEcTED ZONE

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 220-226页

作者： f. chai c.f. Yang H. Su Y.Q. Zhang Z. Xu Y.H. Yang Institute for Structural Materials Central Iron and Steel Research Institute Beijing 100081 China School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China School of Materials Science and Engineering Kunming University of Science and Technology Kunming650093 China

Effects of Zirconium on the chemical component and size distribution of Ti-bearing inclusions, favored the grain refinement of the welding reduced, coarse-grained heat affected zone （cGHAZ） with enhanced impact toughness in Ti-killed steels, which were examined based on experimental observations and thermodynamic calculations. It indicated that the chemical constituents of inclusions gradually varied from the TiO oxide to the Ti-O＋Zr-O compound oxide and a single phase of the ZrO2 oxide, as the Zr content increased from zero to 0.0100%. A trace of Zr （0.0030%-0.0080%, depending on the oxygen content in liquid steel） provided a large amount of nucleating core for Ti oxide because of the larger spec.f.c density of ZrO2 oxide, and produced a small size distribution of the inclusions favorable for acicular ferrite transformation with a high nucleation rate in the cGHAZ, and a high volume fraction of acicular ferrite was obtained in the cGHAZ, with enhanced impact toughness. Otherwise, a high content of Zr （-0.0100%） produced a single phase Zr02, which was impotent to nucleate acicular ferrite, and a microstructure composed of ferrite side plate and grain boundary ferrite developed in the cGHAZ. The experimental results were confirmed by thermodynamic calculations.

关键词： Nonmetallic inclusions Zirconium Acicular ferrite coarse-grain heat affected zone (cGHAZ)

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