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高压直流换流站穿墙套管的局部放电在线测量(英文)

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高电压技术 2011年第11期37卷 2636-2642页

作者： Nathan D.Jacob william m.mcDermid Behzad Kordi Department of Electrical & Computer Engineering University of ManitobaWinnipegCanada Insulation Engineering & Testing Department Manitoba HydroWinnipegCanada

An online partial discharge(PD) measurement performed on a high voltage direct current(HVDC) wall bushing successfully identified the presence of internal *** wall bushing is a sulfur hexafluoride gas-insulated bushing,rated for 500 kV dc and terminated on a thyristor-controlled HVDC converter *** measurement of PD within the HVDC station environment is particularly challenging due to the high levels of electromagnetic noise caused by thyristor switching events and external air-corona from the neighboring high-voltage *** additional challenge is the""mixed"voltage stress on the bushing insulation,which has both ac and dc high-voltage *** are also fast transients during the firing of thyristors in the HVDC conversion process that cause added stress to the *** a result,the analysis and interpretation of PD data for HVDC equipment is more complex;PD pulses may occur in response to the ac,dc,or switching transient voltage *** this paper,an online PD measurement strategy for noise filtering and isolation of PD sources within the bushing are *** PD measurement data is plotted on a phase-resolved diagram where the line supply power cord voltage was used as a reference. The phase-resolved diagram appears to suggest that the fast transients,caused during switching,trigger some PD *** were also performed with the aid of a modern PD measurement instrument having noise separation *** findings from the online PD measurements are verified with physical evidence,found after the bushing was removed from service,suggested internal PD had occurred inside the bushing.

关键词： partial discharge(PD) electrical insulation high voltage direct current(HVDC) converters SF6 electromagnetic interference electromagnetic coupling

A new model to estimate significant wave heights with ERS-1/2 scatterometer data

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Chinese Journal of Oceanology and Limnology 2009年第1期27卷 112-116页

作者：过杰何宜军 william Perrie 申辉储小青 Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Ocean Circulation and Wave CAS Graduate School of the Chinese Academy of Sciences Bedford Institute of Oceanography

A new model is proposed to estimate the significant wave heights with ERS-1/2 scatterometer data. The results show that the relationship between wave parameters and radar backscattering cross section is similar to that between wind and the radar backscattering cross section. Therefore, the relationship between significant wave height and the radar backscattering cross section is established with a neural network algorithm, which is, if the average wave period is ≤7s, the root mean square of significant wave height retrieved from ERS-1/2 data is 0.51 m, or 0.72 m if it is >7s otherwise.

关键词： scatterometer significant wave height neural networks wind waves swell

The Role of Cyclic Nucleotide-Gated Ion Channels in Plant Immunity

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molecular Plant 2011年第3期4卷 442-452页

作者： Wolfgang moeder william Urquhart Huoi Ung Keiko Yoshioka Department of Cell and Systems Biology University of Toronto 25 Willcocks Street Toronto ON M5S 3B2 Canada Center for the Analysis of Genome Evolution and Function (CAGEF) University of Toronto 25 Willcocks Street Toronto ON M5S 3B2 Canada

Since the first plant cyclic nucleotide-gated ion channel （CNGC）, HvCBT1, was identified as a calmodulin bind- ing protein, more than a decade has passed and a substantial amount of work has been done to understand the molecular nature and function of these channel proteins. Based on electrophysiological and heterologous expression analyses, plant CNGCs function as non-selective cation channels and, so far, their biological roles have been reported in defense responses, development, and ion homeostasis. Forward genetic approaches identified four AtCNGCs （AtCNGC2, 4, 11, and 12） to be involved in plant immunity, as null mutants for AtCNGC2, 4, 11, and 12 as well as a gain-of- function mutant for AtCNGC11 and 12 exhibited alterations in defense responses. Since ion flux changes have been reported as one of the early events upon pathogen recognition and also are an essential component for the activation of defense responses, the involvement of CNGCs in these ion flux changes has been suggested. However, the recent detailed characterization of null mutants suggested a more complex involvement of this channel family. In this review, we focus on the discoveries and character- ization of these CNGC mutants and discuss possible roles of CNGCs as components in plant immunity.

关键词： CNGC cyclic nucleotide-gated ion channel plant immunity DND1 DND2 HLm1 CPR22 ED51.

Ground-Based LiDAR Improves Phenotypic Repeatability of Above-Ground Biomass and Crop Growth Rate in Wheat

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Plant Phenomics 2020年第1期2卷 138-148页

作者： David m.Deery Greg J.Rebetzke Jose A.Jimenez-Berni Anthony G.Condon David J.Smith Kathryn m.Bechaz william D.Bovill CSIRO Agriculture and Food CanberraACTAustralia CSIRO Agriculture and Food YancoNSWAustralia NSW Department of Primary Industries YancoNSWAustralia

Highly repeatable,nondestructive,and high-throughput measures of above-ground biomass(AGB)and crop growth rate(CGR)are important for wheat improvement *** study evaluates the repeatability of destructive AGB and CGR measurements in comparison to two previously described methods for the estimation of AGB from LiDAR:3D voxel index(3DVI)and 3D profile index(3DPI).Across three field experiments,contrasting in available water supply and comprising up to 98 wheat genotypes varying for canopy architecture,several concurrent measurements of LiDAR and AGB were made from jointing to *** correlations at discrete events between AGB and the LiDAR-derived biomass indices were significant,ranging from 0.31(Pmass indices at discrete events was at least similar to and often higher than AGB,particularly under water *** correlations between calculated CGR for AGB and the LiDAR indices were moderate to high and varied between ***,across all experiments,the repeatabilities of the CGR derived from the LiDAR indices were appreciably greater than those for AGB,except for the 3DPI in the water-limited *** our experiments,the repeatability of either LiDAR index was consistently higher than that of AGB,both at discrete time points and when CGR was *** findings provide promising support for the reliable use of ground-based LiDAR,as a surrogate measure of AGB and CGR,for screening germplasm in research and wheat breeding.

关键词： Wheat Biomass LiDAR

EEG/ERP evidence of possible hyperexcitability in older adults with elevated beta-amyloid

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Translational Neurodegeneration 2022年第1期11卷 835-844页

作者： Hannes Devos Kathleen Gustafson Ke Liao Pedram Ahmadnezhad Bradley Estes Laura E.martin Jonathan D.mahnken william m.Brooks Jeffrey m.Burns Department of Physical Therapy Rehabilitation Scienceand Athletic TrainingUniversity of Kansas Medical CenterKansas CityKS 66160USA Department of Neurology University of Kansas Medical CenterKansas CityKS 66160USA Hoglund Biomedical Imaging Center University of Kansas Medical CenterKansas CityKS 66160USA Department of Population Health University of Kansas Medical CenterKansas CityKS 66160USA Department of Biostatistics and Data Science University of Kansas Medical CenterKansas CityKS 66160USA University of Kansas Alzheimer’s Disease Center University of Kansas Medical CenterKansas CityKS 66160USA.

Background: Although growing evidence links beta-amyloid (Aβ) and neuronal hyperexcitability in preclinical mouse models of Alzheimer’s disease (AD), a similar association in humans is yet to be established. The first aim of the study was to determine the association between elevated Aβ (Aβ+) and cognitive processes measured by the P3 event-related potential (ERP) in cognitively normal (CN) older adults. The second aim was to compare the event- related power between CNAβ+ and CNAβ−. methods: Seventeen CNAβ+ participants (age: 73 ± 5, 11 females, montreal Cognitive Assessment [moCA] score 26 ± 2) and 17 CNAβ- participants group-matched for age, sex, and mOCA completed a working memory task (n-back with n = 0, 1, 2) test while wearing a 256-channel electro-encephalography net. P3 peak amplitude and latency of the target, nontarget and task difference effect (nontarget−target), and event-related power in the delta, theta, alpha, and beta bands, extracted from Fz, Cz, and Pz, were compared between groups using linear mixed models. P3 ampli-tude of the task difference effect at Fz and event-related power in the delta band were considered main outcomes. Correlations of mean Aβ standard uptake value ratios (SUVR) using positron emission tomography with P3 amplitude and latency of the task difference effect were analyzed using Pearson Correlation Coefficient r. Results: The P3 peak amplitude of the task difference effect at Fz was lower in the CNAβ+ group (P = 0.048). Simi-larly, power was lower in the delta band for nontargets at Fz in the CNAβ+ participants (P = 0.04). The CNAβ+ partici-pants also demonstrated higher theta and alpha power in channels at Cz and Pz, but no changes in P3 ERP. Strong correlations were found between the mean Aβ SUVR and the latency of the 1-back (r = − 0.69;P = 0.003) and 2-back (r = − 0.69;P = 0.004) of the task difference effect at channel Fz in the CNAβ+ group. Conclusions: Our data suggest that the elevated amyloid in cognitively normal ol

关键词： Event-related potentials Electro-encephalography Working memory Older adults Preclinical Beta-amyloid

Cost analysis of childhood glaucoma surgeries using the US medicaire allowable costs

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International Journal of Ophthalmology(English edition) 2023年第5期16卷 700-704页

作者： Abdelrahman m.Elhusseiny mohamed m.Khodeiry Nicolas A.Yannuzzi Ta C.Chang Richard K.Lee william E.Smiddy Department of Ophthalmology Bascom Palmer Eye InstituteUniversity of Miami Miller School of MedicineMiamiFlorida 33136USA Department of Ophthalmology Harvey and Bernice Jones Eye InstituteUniversity of Arkansas for Medical SciencesLittle RockArkansas 72205USA

AIm: To analyze and calculate the relative cost of various childhood glaucoma surgical interventions per mm Hg intraocular pressure(IOP) reduction($/mm Hg).mETHODS: Representative index studies were reviewed to quantitate the reduction of mean IOP and glaucoma medications for each surgical intervention in childhood glaucoma. A US perspective was adopted, using medicare allowable costs to calculate cost/mm Hg IOP reduction($/mm Hg) at 1y ***: At 1y postoperatively, the cost/mm Hg IOP reduction was $226/mm Hg for microcatheter-assisted circumferential trabeculotomy, $284/mm Hg for cyclophotocoagulation, $288/mm Hg for conventional ab-externo trabeculotomy, $338/mm Hg for Ahmed glaucoma valve, $350/mm Hg for Baerveldt glaucoma implant, $351/mm Hg for goniotomy, and $400/mm Hg for ***: microcatheter-assisted circumferential trabeculotomy is the most cost-efficient surgical method to lower IOP in childhood glaucoma, while trabeculectomy is the least cost-efficient surgical method.

关键词： glaucoma cost analysis trabeculotomy trabeculectomy intraocular pressure childhood glaucoma

Stem cell therapy and diabetic erectile dysfunction:A critical review

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World Journal of Stem Cells 2021年第10期13卷 1549-1563页

作者： Cennikon Pakpahan Raditya Ibrahim william william Zakiyatul Faizah Juniastuti Juniastuti maria I Lusida Delvac Oceandy Department of Biomedical Sciences Universitas AirlanggaSurabaya 60132Indonesia Andrology Program Universitas AirlanggaSurabaya 60132Indonesia Department of medical Biology School of Medicine and Health Sciences Atma Jaya Catholic University of IndonesiaJakarta 14440Indonesia Institute of Tropical Disease Universitas AirlanggaSurabaya 60132Indonesia Institute for Tropical Disease Universitas AirlanggaSurabaya 60132Indonesia Division of Cardiovascular Sciences The University of ManchesterManchester Academic Health Science CentreManchester M139PTUnited Kingdom

Erectile dysfunction(ED)has been identified as one of the most frequent chronic complications of diabetes mellitus(Dm).The prevalence of ED is estimated to be about 67.4%in all Dm cases *** pathophysiological process leading to ED involves endothelial,neurological,hormonal,and psychological *** Dm,endothelial and neurological factors play a crucial *** in the blood vessels and erectile tissue due to insulin resistance are the hallmark of ED in *** current treatments for ED include phosphodiesterase-5 inhibitors and penile prosthesis ***,these treatments are limited in terms of just relieving the symptoms,but not resolving the cause of the *** use of stem cells for treating ED is currently being studied mostly in experimental *** stem cells used are derived from adipose tissue,bone,or human *** of the studies observed an improvement in erectile quality in the experimental animals as well as an improvement in erectile ***,research on stem cell therapy for ED in humans remains to be ***,significant findings from studies using animal models indicate a potential use of stem cells in the treatment of ED.

关键词： Stem cells Diabetes mellitus Erectile dysfunction Stem cell therapy Diabetic erectile dysfunction

The effect of performance demands on lower extremity biomechanics during landing and cutting tasks

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Journal of Sport and Health Science 2019年第3期8卷 228-234页

作者： Boyi Dai william E.Garrett michael T.Gross Darin A.Padua Robin m.Queen Bing Yu Division of Kinesiology and Health University of Wyoming Department of Orthopaedic Surgery Duke University Division of Physical Therapy University of North Carolina at Chapel Hill Department of Exercise and Sport Science University of North Carolina at Chapel Hill Kevin Granata Biomechanics Lab Department of Biomedical Engineering and MechanicsVirginia Tech

Background: Anterior cruciate ligament(ACL) injuries commonly occur during the early phase of landing and cutting tasks that involve sudden decelerations. The purpose of this study was to investigate the effects of jump height and jump speed on lower extremity biomechanics during a stop-jump task and the effect of cutting speed on lower extremity biomechanics during a side-cutting ***: Thirty-six recreational athletes performed a stop-jump task under 3 conditions: jumping fast, jumping for maximum height, and jumping for 60% of maximum height. Participants also performed a side-cutting task under 2 conditions: cutting at maximum speed and cutting at 60% of maximum speed. Three-dimensional kinematic and kinetic data were ***:The jumping fast condition resulted in increased peak posterior ground reaction force(PPGRF), knee extension moment at PPGRF,and knee joint stiffness and decreased knee flexion angle compared with the jumping for maximum height condition. The jumping for 60% of maximum height condition resulted in decreased knee flexion angle compared with the jumping for maxrimum height condition. Participants demonstrated greater PPGRF, knee extension moment at PPGRF, knee valgus angle and varus moment at PPGRF, knee joint stiffness, and knee flexion angle during the cutting at maximum speed condition compared with the cutting at 60% maximum speed ***: Performing jump landing at an increased jump speed resulted in lower extremity movement patterns that have been previously associated with an increase in ACL loading. Cutting speed also affected lower extremity biomechanics. Jump speed and cutting speed need to be considered when designing AC.L injury risk screening and injury prevention programs.

关键词： ACL injury Injury prevention Kinematics Kinetics Loading mechanism Risk factor

mechanical suppression of breast cancer cell invasion and paracrine signaling to osteoclasts requires nucleo-cytoskeletal connectivity

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Bone Research 2020年第4期8卷 393-405页

作者： Xin Yi Laura E.Wright Gabriel m.Pagnotti Gunes Uzer Katherine m.Powell Joseph m.Wallace Uma Sankar Clinton T.Rubin Khalid mohammad Theresa A.Guise william R.Thompson Department of Physical Therapy School of Health and Rehabilitation SciencesIndiana UniversityIndianapolisIN 46202USA Department of medicine Division of EndocrinologySchool of MedicineIndiana UniversityIndianapolisIN 46202USA Department of mechanical and Biomedical Engineering Boise State UniversityBoiseID 83725USA Department of Biomedical Engineering Purdue School of Engineering and TechnologyPurdue UniversityIndianapolisIN 46202USA Department of Anatomy&Cell Biology Indiana UniversityIndianapolisIN 46202USA Department of Biomedical Engineering Stony Brook UniversityStony BrookNY 11794USA

Exercise benefits the musculoskeletal system and reduces the effects of *** effects of exercise are multifactorial,where metabolic changes and tissue adaptation influence *** signals,a principal component of exercise,are anabolic to the musculoskeletal system and restrict cancer *** examined the mechanisms through which cancer cells sense and respond to low-magnitude mechanical signals introduced in the form of ***-magnitude,high-frequency vibration was applied to human breast cancer cells in the form of low-intensity vibration(LIV).LIV decreased matrix invasion and impaired secretion of osteolytic factors PTHLH,IL-11,and ***,paracrine signals from mechanically stimulated cancer cells,reduced osteoclast differentiation and resorptive *** the nucleus by knockdown of SUN1 and SUN2 impaired LIV-mediated suppression of invasion and osteolytic factor *** increased cell stiffness;an effect dependent on the LINC *** data show that mechanical vibration reduces the metastatic potential of human breast cancer cells,where the nucleus serves as a mechanosensory apparatus to alter cell structure and intercellular signaling.

关键词： invasion impaired skeletal