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j.urnal of Hydrodynamics 2014年第2期26卷 277-290页

作者： TRIVEDI Chirag cervantes michel j. GANDHI B.K. OLE DAHLHAUG G. Division of Fluid and Experimental Mechanics Department of Engineering Sciences and Mathematics Lule? University of Technology Department of Mechanical and Industrial Engineering Indian Institute of Technology Water Power Laboratory Department of Energy and Process Engineering Norwegian University of Science and Technology

Penetration of the power generated using wind and solar energy to electrical grid network causing several incidents of the grid tripping, power outage, and frequency drooping. This has increased restart （star-stop） cycles of the hydroelectric turbines significantly since grid connected hydroelectric turbines are widely used to manage critical conditions of the grid. Each cycle induces significant stresses due to unsteady pressure loading on the runner blades. The presented work investigates the pressure loading to a high head （ He = 377 m, De = 1.78 m） Francis turbine during start-stop. The measurements were carried out on a scaled model turbine （HM = 12.5 m, DM = 0.349 m）. Total four operating points were considered. At each operating point, three schemes of guide vanes opening and three schemes of guide vanes closing were investigated. The results show that total head variation is up to 9% during start-stop of the turbine. On the runner blade, the maximum pressure amplitudes are about 14 kPa and 16 kPa from the instantaneous mean value of 121 kPa during rapid start-up and shutdown, respectively, which are about 1.5 times larger than that of the slow start-up and shutdown. Moreover, the maximum pressure fluctuations are given at the blade trailing edge.

关键词： Francis turbine pressure fluctuations start-up shutdown transient

Bivariate Analysis of Pollutants Monthly Maxima in Mexico City Using Extreme Value Distributions and Copula

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j.urnal of Environmental Protection 2024年第7期15卷 796-826页

作者： j.an A. Vazquez-Morales Eliane R. Rodrigues Hortensia j. Reyes-cervantes Facultad de Ciencias Fsico-Matemticas Benemrita Universidad Autnoma de Puebla Puebla Mexico Instituto de Matemticas Universidad Nacional Autnoma de Mxico Mexico City Mexico

In the present work, we are interested in studying the j.int distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metropolitan area. In order to obtain the j.int distributions a copula will be considered. Since we are analyzing the monthly maxima, the extreme value distributions of Weibull and Fréchet are taken into account. Using these two distributions as marginal distributions in the copula a Bayesian inference was made in order to estimate the parameters of both distributions and also the association parameters appearing in the copula model. The pollutants taken into account are ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide, and particulate matter with diameters smaller than 10 and 2.5 microns obtained from the Mexico City monitoring network. The estimation was performed by taking samples of the parameters generated through a Markov chain Monte Carlo algorithm implemented using the software OpenBugs. Once the algorithm is implemented it is applied to the pairs of pollutants where one of the coordinates of the pair is ozone and the other varies on the set of the remaining pollutants. Depending on the pollutant and the region where they were collected, different results were obtained. Hence, in some cases we have that the best model is that where we have a Fréchet distribution as the marginal distribution for the measurements of both pollutants and in others the most suitable model is the one assuming a Fréchet for ozone and a Weibull for the other pollutant. Results show that, in the present case, the estimated association parameter is a good representation to the correlation parameters between the pair of pollutants analyzed. Additionally, it is a straightforward task to obtain these correlation parameters from the corresponding association parameters.

关键词： Copula Extreme Value Distribution Bayesian Inference Air Pollution Mexico City

Single-cell transcriptome atlases of soybean root and mature nodule reveal new regulatory programs that control the nodulation process

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Plant Communications 2024年第8期5卷 69-91页

作者： Sergio Alan cervantes-Perez Prince Zogli Sahand Amini Sandra Thibivilliers Sutton Tennant Md Sabbir Hossain Hengping Xu Ian Meyer Akash Nooka Pengchong Ma Qiuming Yao Michael j.Naldrett Andrew Farmer Olivier Martin Samik Bhattacharya j.sper Klaver Marc Libault Department of Agronomy and Horticulture University of Nebraska-LincolnLincolnNE 68503USA Division of Plant Science and Technology College of AgricultureFoodand Natural ResourcesUniversity of Missouri-ColumbiaColumbiaMO 65211USA Interdisciplinary Plant Group of Missouri-Columbia ColumbiaMO 65211USA School of Computing University of Nebraska-LincolnLincolnNE 68503USA Proteomics and Metabolomics Facility Center for BiotechnologyUniversity of Nebraska-LincolnLincolnNE 68588USA National Center for Genome Resources Santa FeNM 87505USA INRAE UniversiteParis-SaclayInstitut des Sciences des Plantes de Paris SaclayIPS2Batiment 630 Plateau du MoulonRue Noetzlin91192 Gif sur Yvette CedexFrance Resolve Biosciences Monheim am RheinGermany Present address:The School of Plant Sciences University of ArizonaTucsonAZ 85721USA Present address:GALY Co. 100 Hood Park Dr.BostonMA 02126USA

The soybean root system is *** addition to being composed of various cell types,the soybean root system includes the primary root,the lateral roots,and the nodule,an organ in which mutualistic symbiosis with N-fixing rhizobia occurs.A mature soybean root nodule is characterized by a central infection zone where atmospheric nitrogen is fixed and assimilated by the symbiont,resulting from the close cooperation between the plant cell and the *** date,the transcriptome of individual cells isolated from developing soybean nodules has been established,but the transcriptomic signatures of cells from the mature soybean nodule have not yet been *** single-nucleus RNA-seq and Molecular Cartography technologies,we precisely characterized the transcriptomic signature of soybean root and mature nodule cell types and revealed the co-existence of different sub-populations of ***-infected cells in the mature soybean nodule,including those actively involved in nitrogen fixation and those engaged in *** of the single-cell-resolution nodule transcriptome atlas and the associated gene co-expression network confirmed the role of known nodulation-related genes and identified new genes that control the nodulation *** instance,we functionally characterized the role of GmFWL3,a plasma membrane microdomain-associated protein that controls rhizobial *** study reveals the unique cellular complexity of the mature soybean nodule and helps redefine the concept of cell types when considering the infection zone of the soybean nodule.

关键词： soybean root nodule single-cell RNA-seq nanodomains

Human Eosinophil Cell Manipulation by Optical Tweezers

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Open j.urnal of Biophysics 2024年第3期14卷 330-338页

作者： Pavel Yale j.an michel Edoukoua Konin Abadê Ange-Boris N’guessan michel Abaka Kouacou j.rémie T. Zoueu Laboratoire dInstrumentation Image et Spectroscopie (L2IS) Institut National Polytechnique Houphout-Boigny (INPHB) Yamoussoukro Cte dIvoire Laboratoire de Chimie et de Physique Appliques Sciences et Techniques Universit Alassane Ouattara Bouak Cte dIvoire

In this work, lateral deformation of human eosinophil cell during the lateral indentation by an optically trapped microbead of diameter 4.5 µm is studied. The images were captured using a CCD camera and the Boltzmann statistics method was used for force calibration. Using the Hertz model, we calculated and compared the elastic moduli resulting from the lateral force, showing that the differences are important and the force should be considered. Besides the lateral component, the setup also allows us to examine the lateral cell-bead interaction. The mean values of the properties obtained, in particular the elastic stiffness and the shear stiffness, were Eh = (37.76 ± 2.85) µN/m and Gh = (12.57 ± 0.32) µN/m. These results show that the lateral indentation can therefore be used as a routine method for cell study, because it enabled us to manipulate the cell without contact with the laser.

关键词： Optical Tweezers Human Eosinophil Cell Indentation Shear Stiffness

Viscoelasticity and shear-thinning effects on bio-polymer solution and suspended particle behaviours under oscillatory curve Couette flow conditions

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Biosurface and Biotribology 2018年第1期4卷 1-17页

作者： Alaleh Safari Nazanin Emami michel j.se cervantes Biotribology Group Division of Machine ElementLulea University of Technology97187 LuleaSweden Division of Fluid and Experimental Mechanics Lulea University of Technology97187 LuleàSweden Water Power Laboratory Norwegian University of Science and Technology7491 TrondheimNorway

Formation of wear particles within total hip replacement is one of the main causes of its *** addition toimproving the lubrication and wear resistance of materials used as bearing surfaces,understanding of wear particledistribution patterns within lubricants inside an implant gap could be used to improve design parameters andimplants'*** this study,the behaviours of biolubricants(with compositions similar to human j.int synovialfluid)and suspended particles were investigated by micro-particle image velocimetry in curved mini channels underoscillatory Couette flow *** studied biolubricants had shear-thinning viscoelastic *** found that increasing shear-thinning,elasticity or motion frequency levels did not affect the trend behavioursof biolubricant flows due to the low strain values of the experimental conditions ***,suspended particlesformed strings along flow directions and exhibited cross-stream migration to channel *** frequency,fluidshear thinning and elasticity characteristics and channel dimensions strongly affected particle behaviours.

关键词： particle oscillatory flow

Evaluating physical changes of iron oxide nanoparticles due to surface modification with oleic acid

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Chinese Physics B 2020年第10期29卷 186-194页

作者： S Rosales N Casillas A Topete O cervantes G González j.A Paz M E Cano Centro Universitario de Ciencias Exactas e Ingenienas Universidad de GuadalajaraBlvd.Marcelino Garcia Burragan 1421C.P.44430GuadalajaraJaliscoMexico Centro Universitario de la Cienegu Universidad de GuadalajaraAv.Universidad 1115C.P.47820OcotlanJaliscoMexico Centro Universitario de Ciencias de In Salud Universidad de Guadalajara.Sierra Mojada 950C.P.44340GuadalajaraJaliscoMexico

The physical characterization of a colloidal system of superficially modified magnetic nanoparticles (MNPs) is presented. The system consists of oleic acid-coated iron oxide nanoparticles (OAMNP) suspended in water. A structural analysis is carried out by using standard physical techniques to determine the diameter and shape of the MNPs and also the width of the coating shell. The colloidal stability and the polydispersity index of this ferrofluid are determined by using Zeta potential measurements. Additionally, the magnetic characterization is conducted by obtaining the DC magnetization loops, and the blocking temperatures are determined according to the ZFC–FC protocol. Finally, the values of power absorption density P of the ferrofluid are estimated by using a magneto-calorimetric procedure in a wide range of magnetic field amplitude H and frequency f. The experimental results exhibit spherical-like shape of OAMNP with (20 ± 4) nm in diameter. Due to the use of coating process, the parameters of the magnetization loops and the blocking temperatures are significantly modified. Hence, while the uncoated MNPs show a blocking state of the magnetization, the OAMNP are superparamagnetic above room temperature (300 K). Furthermore, the reached dependence P versus f and P versus H of the ferrofluid with coated MNPs are clearly fitted to linear and quadratic correlations, respectively, showing their accordance with the linear response theory.

关键词： nanoparticles ferrofluid magnetic hyperthermia functionalization

Resolution of phylogenetic relationships of the maj.r subfamilies of the Delphacidae （Homoptera： Fulgoroidea） using the mitochondrial ribosomal DNA

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Insect Science 2006年第3期13卷 167-177页

作者： EDDY DIj.STRA michel A. SLOTMAN RORY j. POST Biosystematics Group Wageningen University the Netherlands The Natural History Museum London UK

Delphacid relationships from the genus level to the subfamily have been completely resolved （among those taxa examined） using sequence data from the 3＇ end of the 12S gene. Monophyly of the non-asiracine subfamilies was strongly supported and the asiracine Ugyops was placed in the most basal position of the tree. Support levels for monophyly of the Delphacini increased after weighting transversions more heavily than transitions and after removing the cixiid outgroup from the dataset. Among the Delphacini, Conomelus and Megamelus were more closely related to each other than either was to Chloriona. These results are in agreement with the tree based on morphological characters. However, in contrast to morphological data our results strongly supported a sister group relationship between the Stenocraninae and the Kelisiinae. Although the 12S gene fragment gave some information about the species relationships within Chloriona, neither this fragment nor the 5＇ end of the 16S gene appear to be very useful for this level. Molecular evolutionary patterns provided evidence that there has been a shift in base composition from T to A during the early evolution of the non-Asiracinae. The non-Asiracinae also had comparatively fast substitution rates and these two observations are possibly correlated. In the ‘ modem＇ delphacid Chloriona, the AT content was comparatively low in regions free of constraints but this was not the case for ‘ non-modem＇ delphacids. The tRNA for valine has been translocated elsewhere, probably before the Delphacidae and Cixiidae diverged from each other.

关键词： classification Delphacidae evolution Fulgoroidea Homoptera rnitochondrial DNA phylogeny ribosomal DNA

Experimental investigation of flow pattern and sediment deposition in rectangular shallow reservoirs

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International j.urnal of Sediment Research 2010年第3期25卷 258-270页

作者： Matthieu DUFRESNE Benj.min j. DEWALS Sébastien ERPICUM Pierre ARCHAMBEAU michel PIROTTON University of Liège (ULg) ArGEnCO department MS2F sector Hydrology applied hydrodynamics and hydraulic constructions (HACH) Chemin des chevreuils 1 bat B52/3 étage +1 4000 Liège Belgium University of Liège (ULg) ArGEnCO department MS2F sector Hydrology applied hydrodynamics and hydraulic constructions (HACH) Chemin des chevreuils 1 bat B52/3 étage +1 4000 Liège Belgium.

This paper reports the experimental investigation of flow pattern, preferential regions of deposition and trap efficiency as a function of the length of rectangular shallow reservoirs. Four flow patterns were identified (from longer to shorter reservoirs): an asymmetric flow with two reattachment points, an asymmetric flow with one reattachment point, an unstable flow, and a symmetric flow without any reattachment point. Using dye visualizations, the median value and the temporal variability of the reattachment lengths were precisely measured for the asymmetric flows. For each stable flow, sediment tests with plastic particles were carried out. The regions of deposition on the bed of the reservoir were clearly a function of the flow pattern. The transition from an asymmetric flow pattern to a symmetric flow pattern was responsible for an abrupt decrease of the trap efficiency; a number of regression laws were discussed to take it into account.

关键词： Deposition Flow patterns Reservoirs Sediment Shallow water

Cellular Auxin Homeostasis： Gatekeeping Is Housekeeping

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Molecular Plant 2012年第4期5卷 772-786页

作者： michel Ruiz Rosquete Department of Applied Genetics and Cell Biology University of Applied Life Sciences and Natural Resources (BOKU) 1190 Vienna Austria Department of Plant Systems Biology VIB and Department of Plant Biotechnology and Bioinformatics Ghent University 9052 Gent Belgium

The phytohormone auxin is essential for plant development and contributes to nearly every aspect of the plant life cycle. The spatio-temporal distribution of auxin depends on a complex interplay between auxin metabolism and cell-to-cell auxin transport. Auxin metabolism and transport are both crucial for plant development; however, it largely remains to be seen how these processes are integrated to ensure defined cellular auxin levels or even gradients within tissues or organs. In this review, we provide a glance at very diverse topics of auxin biology, such as biosynthesis, conj.gation, oxidation, and transport of auxin. This broad, but certainly superficial, overview highlights the mutual importance of auxin metabolism and transport. Moreover, it allows pinpointing how auxin metabolism and transport get integrated to j.intly regulate cellular auxin homeostasis. Even though these processes have been so far only separately studied, we assume that the phytohormonal crosstalk integrates and coordinates auxin metabolism and transport. Besides the integrative power of the global hormone signaling, we additionally introduce the hypothetical concept considering auxin transport components as gatekeepers for auxin responses.

关键词： auxin conj.gation auxin homeostasis auxin metabolism auxin transport.

Shape Optimization of A 3D Slider with Dimples

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j.urnal of Civil Engineering and Architecture 2012年第12期6卷 1599-1607页

作者： michel cervantes SamuleCupillard Kevin Bance Michael Kokkolaras Division of Fluid and Experimental Mechanics Lulea University of Technology Lulea 971 87 Sweden Hydro-Quebec Research Institute Quebec J3X 1S1 Canada National Institute for Applied Science Rouen 76800 France Department of Mechanical Engineering McGill University Montreal Quebec H3A 0C3 Canada

Sliding contacts in laminar flow regimes have been investigated extensively in recent years. The results indicate the possibility to increase load carrying capacity in a slider bearing for more than 10% with the addition of dimples. Parametric studies have been performed to determine optimal size and position, with emphasis in the optimal shape and position of the dimple for an operating condition. In this article, the numerical analysis of a 2D textured slider bearing with a dimple is initially considered with an isothermal laminar fluid. Position, depth, width and convergence ratio are optimized, the results demonstrate the importance of the width and convergence ratio to increase load. Then, the numerical analysis of a 3D textured slider bearing with fore-region and extended channels at the outlet and on the sides of a pad is considered. The simulations are also carried out for a laminar isothermal flow. Three dimples are considered and their depth is optimized.

关键词： Sliding contact laminar texture dimple optimization.