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In-situ investigation on real-time suspended sediment measurement techniques:Turbidimetry, acoustic attenuation,laser diffraction (LISST) and vibrating tube densimetry

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International Journal of Sediment Research 2018年第1期33卷 3-17页

作者： David Felix Ismail Albayrak robert michael boes Laboratory of Hydraulics Hydrology and Glaciology(VAW)ETH Zürich

Real-time measurements of Suspended Sediment mass Concentration（SSC） and Particle Size Distribution（PSD） are of prime importance for the investigation and management of fine-sediment related processes in surface water systems and hydraulic schemes. In a field study at the waterway of the hydropower plant（HPP） Fieschertal in the Swiss Alps, the real-time measurement performance of the following techniques and instruments were assessed based on measurements in the sediment seasons of the years 2013 and 2014:（1） turbidimetry,（2） single-frequency acoustic attenuation using a standard acoustic discharge measurement（ADM） installation,（3） laser diffraction（Laser In-Situ Scattering and Transmissometry, LISST）, and（4） vibrating tube densimetry using a Coriolis Flow and Density Meter（CFDM）.Reference SSCs were obtained from gravimetric analysis of 219 automatically pumped water *** additionally supplied PSD every minute. The median particle diameter, d50, was usually 15μm and increased occasionally to 100μm. The turbidimeter and the ADM underestimated the SSC when the transported particles were coarser than usual. Such temporary biases resulted from the poor correlation between d50and SSC at this study site. The SSCs from CFDM and LISST were not or less biased by PSD variations. Mainly due to angular and flaky particle shapes, SSC from LISST needed a correction by 79% on average. With the usually prevailing silt particles, an optical path length of 5 mm and no dilution, the SSC measurement range of LISST was limited to about 1.5 g/l. The CFDM allowed measuring higher SSC than the other investigated instruments（e.g. up to 13.5 g/l）. With a periodic offset correction, its relative SSC measurement uncertainty was < 20% for SSC≥ 1.5 g/I. To reliably measure a wide range of SSC with temporarily variable PSD, a combination of instruments is recommended: e.g. a standard LISST, a CFDM,and an automatic water sampler for gravimetric reference measurements.

关键词： Suspended sediment concentration Turbidity Acoustic attenuation Laser diffraction Coriolis flow and density meter Gravimetric analysis

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Erosion pattern of artificial gravel deposits

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International Journal of Sediment Research 2018年第1期33卷 57-67页

作者： Fabian Friedl Volker Weitbrecht robert M.boes Laboratory of Hydraulics Hydrology and Glaciology (VAW)ETH Zurich

Sediment replenishment with artificial gravel deposits is an option to compensate for sediment deficits in rivers and to improve their ecological conditions. Predicting and quantifying the erosion rate of an artificial gravel deposit is important to successfully perform river restoration projects. Laboratory experiments have been done to investigate the influence of various parameters on the erosion pattern of artificial gravel deposits. In the present paper the effects of deposit geometry, bulk density, grain size distribution, and hydraulic load on the erosion process are described. The temporal evolution of the deposit geometry and the corresponding mean erosion rates were studied. The mean erosion rate increases with deposit height, deposit width, and decreasing grain size. Furthermore, no significant impact of the bulk density was observed. Equations to predict the mean erosion rate are proposed. This investigation helps to determine the design frequency of gravel dumping and deposit volumes for restoration projects.

关键词： Artificial gravel deposits Bed load transport Laboratory experiments Sediment replenishment

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Value of incorporating geospatial information into the prediction of on-street parking occupancy - A case study

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Geo-Spatial Information Science 2021年第3期24卷 438-457页

作者： michael Balmer robert Weibel Haosheng Huang Department of Geography University of ZurichZurichSwitzerland Department of Geography Ghent UniversityGhentBelgium

In light of growing urban traffic,car parking becomes increasingly critical for cities to *** a result,the prediction of parking occupancy has sparked significant research interest in recent *** many external data sources have been considered in the prediction models,the underlying geographic context has mostly been ***,in order to study the contribution of geospatial information to parking occupancy prediction models,road network centrality,land use,and Point of Interest(POI)data were incorporated in Random Forest(RF)and Artificial Neural Network(ANN,specifically Feedforward Neural Network FFNN)prediction models in this *** performances were compared to a baseline,which only considers historical and temporal input ***,the influence of the amount of training data,the prediction horizon,and the spatial variation of the prediction were *** results show that the inclusion of geospatial information led to a performance improvement of up to 25%compared to the ***,as the prediction horizon expanded,predictions became less reliable,while the relevance of geospatial data *** general,land use and POI data proved to be more beneficial than road network *** amount of training data did not have a significant influence on the performance of the RF *** ANN model,conversely,achieved optimal results on a training input of 5 *** attributable to varying occupancy patterns,prediction performance disparities could be identified for different parking districts and street ***,the RF model outperformed the ANN model on all predictions.

关键词： Parking occupancy prediction on-street parking geospatial information machine learning

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Apparent Polar Wander Path from the Tarim Block in China

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Acta Geologica Sinica(English Edition) 1990年第1期64卷 1-13页

作者： robert Sharps michael McWilliams Geophysics Dept. Stanford Univ.StanfordCA94305

The apparent polar wander (APW) path from the Tarim block consists of palaeo-magnetic poles ofDevonian (λ=16°N, ψ= 165° E. A_(95)=4°). Late Carboniferous (λ=41° N, ψ=160° E, A_(95)=4°).Permian (λ=61°N, ψ=177° E. A_(95)=9°). Early Triassic (λ=69° N. ψ=183° E. A_(95)=11°) andJurassic/Cretaceous (λ=65° N, ψ=214° E. A_(95)=6°) times. On the basis of this APW path, it is con-cluded that the Tarim block was subducted beneath the Kazakstan plate between Devonian and Permiantimes. The Tarim, North China and South China blocks were sutured between the Early Triassic and EarlyCretaceous. Tarim had moved eastward some 2000 km relative to Siberia since the Cretaceous.

关键词： Apparent Polar Wander Path from the Tarim Block in China Path

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Towards geospatial semantic search:exploiting latent semantic relations in geospatial data

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International Journal of Digital Earth 2014年第1期7卷 17-37页

作者： Wenwen Li michael FGoodchild robert Raskin GeoDa Center for Geospatial Analysis and Computation School of Geographical Science and Urban PlanningArizona State UniversityTempeAZUSA Center for Spatial Studies(Spatial@UCSB) University of CaliforniaSanta BarbaraCAUSA NASA Jet Propulsion Laboratory PasadenaCAUSA

This paper reports our efforts to address the grand challenge of the Digital Earth vision in terms of intelligent data discovery from vast quantities of geo-referenced *** propose an algorithm combining LSA and a Two-Tier Ranking(LSATTR)algorithm based on revised cosine similarity to build a more efficient search engine-Semantic Indexing and Ranking(SIR)-for a semantic-enabled,more effective data *** addition to its ability to handle subject-based search,we propose a mechanism to combine geospatial taxonomy and Yahoo!GeoPlanet for automatic identification of location information from a spatial query and automatic filtering of datasets that are not spatially *** metadata set,in the format of ISO19115,from NASA's SEDAC(Socio-Economic Data Application Center)is used as the corpus of *** show that our semantic search engine SIR built on LSATTR methods outperforms existing keyword-matching techniques,such as Lucene,in terms of both recall and ***,the semantic associations among all existing words in the corpus are *** associations provide substantial support for automating the population of spatial *** expect this work to support the operationalization of the Digital Earth vision by advancing the semantic-based geospatial data discovery.

关键词： ontology geospatial semantics search engine Digital Earth similarity search effectiveness

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Role of imaging in predicting response to neoadjuvant chemotherapy in gastric cancer

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World Journal of Gastroenterology 2014年第7期20卷 1650-1656页

作者： robert michael Kwee Thomas Christian Kwee Department of Radiology Maastricht University Medical Center6229 HX MaastrichtThe Netherlands Department of Radiology University Medical Center Utrecht3584 CX UtrechtThe Netherlands

With the proven overall benefit of neoadjuvant chemotherapy in patients with locally advanced gastric cancer,there has come a need to discriminate responders from *** this article,the current role of anatomical and molecular imaging in the prediction of response to neoadjuvant therapy in gastric cancer is outlined and future prospects are discussed.

关键词： Gastric cancer Neoadjuvant therapy Chemotherapy Response Imaging

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Epigenetic Repression of Male Gametophyte- Specific Genes in the Arabidopsis Sporophyte

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Molecular Plant 2013年第4期6卷 1176-1186页

作者： robert D. Hoffmann michael G. Palmgren Centre for Membrane Pumps in Cells and Disease--PUMPKIN Danish National Research Foundation Department of Plant and Environmental SciencesUniversity of Copenhagen Thorvaldsensvej 40 DK-1871 Frederiksberg Denmark

Tissue formation, the identity of cells, and the functions they fulfill, are results of gene regulation. The male gametophyte of plants, pollen, is outstanding in this respect as several hundred genes expressed in pollen are not expressed in the sporophyte. How pollen-specific genes are down-regulated in the sporophyte has yet to be established. In this study, we have performed a bioinformatics analysis of publicly available genome-wide epigenetics data of sev- eral sporophytic tissues. By combining this analysis with DNase ! footprinting data, we assessed means by which the repression of pollen-specific genes in the Arabidopsis sporophyte is conferred. Our findings show that, in seedlings, the majority of pollen-specific genes are associated with histone-3 marked by mono- or trimethylation of Lys-27 （H3K27me1/ H3K27me3）, both of which are repressive markers for gene expression in the sporophyte. Analysis of DNase footprint profiles of pollen-specific genes in the sporophyte displayed closed chromatin proximal to the start codon. We describe a model of two-staged gene regulation in which a lack of nucleosome-free regions in promoters and histone modifications in open reading frames repress pollen-specific genes in the sporophyte.

关键词： male gametophyte epigenetics gene repression DNase I footprinting transcription factors bioinformatics.

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Zebrafish embryo toxicity of 15 chlorinated, brominated, and iodinated disinfection by-products

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Journal of Environmental Sciences 2017年第8期29卷 302-310页

作者： David Hanigan Lisa Truong michael Simonich robert Tanguay Paul Westerhoff Department of Civil and Environmental Engineering University of Nevada School of Sustainable Engineering and the Built Environment Arizona State University Department of Environmental and Molecular Toxicology Oregon State University

Disinfection to protect human health occurs at drinking water and wastewater facilities through application of non-selective oxidants including chlorine. Oxidants also transform organic material and form disinfection by-products（DBPs）, many of which are halogenated and cyto-and genotoxic. Only a handful of assays have been used to compare DBP toxicity,and researchers are unsure which DBP（s） drive the increased cancer risk associated with drinking chlorinated water. The most extensive data set employs an in vitro model cell,Chinese hamster ovary cells. Traditionally, most DBP research focuses on the threat to human health, but the effects on aquatic species exposed to DBPs in wastewater effluents remain ill defined. We present the developmental toxicity for 15 DBPs and a chlorinated wastewater to a model aquatic vertebrate, zebrafish. Mono-halogenated DBPs followed the in vivo toxicity rank order： acetamides 〉 acetic acids 〉 acetonitriles ~ nitrosamines, which agrees well with previously published mammalian in vitro data. Di-and tri-halogenated acetonitriles were more toxic than their mono-halogenated analogues, and bromine-and iodine-substituted DBPs tended to be more toxic than chlorinated analogues. No zebrafish development effects were observed after exposure to undiluted or non-concentrated,chlorinated wastewater. We find zebrafish development to be a viable in vivo alternative or confirmatory assay to mammalian in vitro cell assays.

关键词： Zebrafish Disinfection by-product Developmental Ecological Toxicity

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Functional Interaction of the SNARE Protein NtSyp121 in Ca^2＋ Channel Gating, Ca^2＋ Transientsand ABA Signalling of Stomatal Guard Cells

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Molecular Plant 2008年第2期1卷 347-358页

作者： Sergei Sokolovski Adrian Hills robert A. Gay michael R. Blatt Laboratory of Plant Physiology and Biophysics IBLS--Plant Sciences University of Glasgow Glasgow G12 8QQ UK Current address: Blackfriars 64 St Giles Oxford OX1 3LY UK

There is now growing evidence that membrane vesicle trafficking proteins, especially of the superfamily of SNAREs, are critical for cellular signalling in plants. Work from this laboratory first demonstrated that a soluble, inhibitory （dominant-negative） fragment of the SNARE NtSyp121 blocked K^＋ and CI^- channel responses to the stress-related hormone abscisic acid （ABA）, but left open a question about functional impacts on signal intermediates, especially on Ca^2＋-mediated signalling events. Here, we report one mode of action for the SNARE mediated directly through alterations in Ca^2＋ channel gating and its consequent effects on cytosolic-free [Ca^2＋] （[Ca^2＋]i） elevation. We find that expressing the same inhibitory fragment of NtSyp121 blocks ABA-evoked stomatal closure, but only partially suppresses stomatal closure in the presence of the NO donor, SNAP, which promotes [Ca^2＋]i elevation independently of the plasma membrane Ca^2＋ channels. Consistent with these observations, Ca^2＋ channel gating at the plasma membrane is altered by the SNARE fragment in a manner effective in reducing the potential for triggering a rise in [Ca^2＋]i, and we show directly that its expression in vivo leads to a pronounced suppression of evoked [Ca^2＋]i transients. These observations offer primary evidence for the functional coupling of the SNARE with Ca^2＋ channels at the plant cell plasma membrane and, because [Ca^2＋]i plays a key role in the control of K^＋ and CI^- channel currents in guard cells, they underscore an important mechanism for SNARE integration with ion channel regulation during stomatal closure.

关键词： Ca^2+ channel, hyperpolarization-activated abscisic acid membrane vesicle traffic cytosolic-free [Ca^2+]elevation Nicotiana plant pathogen defense.

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Mycetismus:a review

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Gastroenterology Report 2016年第2期4卷 107-112,I0001页

作者： michael R.Smith robert L.Davis Department of Surgery St.Barnabas HospitalBronxNYUSA Department of Surgery Lutheran Medical CenterBrooklynNYUSA

Although rare,death from amanitin exposure poses a significant health risk and a diagnostic challenge to the clinician due to its *** is one of the few conditions to be voluntarily reported by healthcare *** antidote exists for this poisoning and,perhaps due to its rarity or lack of attention,the United States has lagged behind Europe for almost three decades in treatment,diagnostics and *** regrettable fact warrants the formation of a centralized agency for education,the advancement of research and the collection of data,to provide better treatment for the population.

关键词： amanita phalloides mushroom poisoning amatoxin amanitin vitamin C cimetidine silibinin N-acetylcysteine liver transplantation Ganzert criteria King’s College criteria mycetismus Clichy criteria

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