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Structure-function Aspects of Extracellular Leucine-rich Repeat-containing Cell Surface Receptors in plants

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Journal of Integrative plant Biology 2013年第12期55卷 1212-1223页

作者： Zhao Zhang Bart p.h.J.Thomma Laboratory of phytopathology Wageningen University Centre for BioSystems Genomics

plants exploit several types of cell surface receptors for perception of extracellular signals, of which the extracellular leucine-rich repeat （eLRR）-containing receptors form the major class. Although the function of most plant eLRR receptors remains unclear, an increasing number of these receptors are shown to play roles in innate immunity and a wide variety of developmental processes. Recent efforts using domain swaps, gene shuffling analyses, site-directed mutagenesis, interaction studies, and crystallographic analyses resulted in the current knowledge on ligand binding and the mechanism of activation of plant eLRR receptors. This review provides an overview of eLRR receptor research, specificallysummarizing the recent understanding of interactions among plant eLRR receptors, their co-receptors and corresponding ligands. The functions of distinct eLRR receptor domains, and their role in structure, ligand perception and multimeric complex formation are discussed.

关键词： eLRR receptor-like kinase (RLK) receptor-like protein (RLp) pathogen-associated molecular pattern (pAMp) effector peptide ligand brassinosteroid CLE peptide.

Changes in Seasonal patterns of Temperature and precipitation in China During 1971-2000

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Advances in Atmospheric Sciences 2007年第3期24卷 459-473页

作者：宋连春 A.J.CANNON p.h.WhITFIELD Institue of Arid Meteorology China Meteorological Administration Department of Earth and Ocean Sciences University of British Columbia VancouverBritish Columbia V6T 1Z2Canada Meteorological Service of CanadaEnvironment Canada#201-401 Burrard Street VancouverBritish Columbia V6C 3S5Canada Meteorological Service of Canada Environment Canada #201-401 Burrard Street VancouverBritish Columbia V6C 3S5Canada

Many studies have shown evidence for significant changes in surface climate in different regions of the world and during different seasons over the past 100 years. Based on daily temperature and precipitation data from 720 climate stations in China, cluster analysis was used to identify regions in China that have experienced similar changes in the seasonal cycle of temperature and precipitation during the 1971-2000 climate normal period. Differences in 11-day averages of daily mean temperature and total precipitation between the first （1971-1985） and second （1986-2000） halves of the record were analyzed using the Mann- Whitney U test and the global κ-means clustering algorithm. Results show that most parts of China experienced significant increases in temperature between the two periods, especially in winter, although some of this warming may be attributable to the urban heat island effect in large cities. Most of western China experienced more precipitation in 1986-2000, while precipitation decreased in the Yellow River valley. Changes in the summer monsoon were also evident, with decreases in precipitation during the onset and decay phases, and increases during the wettest period.

关键词： κ-means clustering seasonality trends temperature precipitation China

An evaluation of a catch and release trout regulation in Rapid Creek,South Dakota

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Aquaculture and Fisheries 2023年第5期8卷 558-563页

作者： Jacob L.davis South Dakota Department of Game Fish and Parks4130 Adventure TrailRapid CitySD57702USA

Often,catch and release regulations are meant to maximize a fisheries potential to create trophy fish.I evaluated adult Brown Trout populations at five locations within Rapid Creek within Rapid City,SD over a two-year *** each year,one of these locations was within a catch and release area,while two were *** 2012,density and biomass estimates were higher in a site located outside of the catch and release ***,size structure within the catch and release area was only significantly larger than one of the two sites outside of the regulation *** relative weight values were inversely related to density estimates,with the lowest density sites having the highest mean relative ***,a site outside of the catch and release area had the highest abundance and biomass estimates in *** cumulative length distribution was significantly different between the site within the catch and release area and the two located *** weight was significantly higher in the catch and release area than the two sites *** population characteristics within the catch and release area were not consistently better than outside,it is more likely that factors such as habitat and density dependence are impacting the Brown Trout population more than the regulation itself.

关键词： Trout Regulations Catch and release

Experimental investigation and prediction of wear behavior of cotton fiber polyester composites

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Friction 2017年第2期5卷 183-193页

作者： hiral h.pARIKh piyush p.GOhIL Department of Mechanical Engineering School of Science and Engineering Navrachana University Vadodara 391410 India Department of Mechanical Engineering Faculty of Technology & Engineering the MS University of Baroda Kalabhavan Vadodara 390001 India

The cotton fiber reinforced polyester composites were fabricated with varying amount of graphite fillers (0,3,5 wt.％) with a hand lay-up *** tests were planned by using a response surface (Box Behnken method) design of experiments and conducted on a pin-on-disc machine (pOD) test *** effect of the weight percentage of graphite content on the dry sliding wear behavior of cotton fiber polyester composite (CFpC) was examined by considering the effect of operating parameters like load,speed,and sliding *** wear test results showed the inclusion of 5 wt.％ of graphite as fillers in CFpC increase wear resistance compared to 3 wt.％ of graphite *** graphite fillers were recommended for CFpC to increase the wear resistance of the material.A scanning electron microscope (SEM) was used to study the wear *** predict the wear behavior of the composite material,comparisons were made between the general regression technique and an artificial neural network (ANN).The conformation test results revealed the predicted wear with the ANN was acceptable when compared with the actual experimental results and the regression mathematical models.

关键词： wear composites cotton fiber reinforced polyester composites artificial neural network pin-on-disc

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眼科学报 1991年第1期7卷 6-20页

作者： h p.h.idenkummer University Eye hospital Wuerzburg Germany

About 1.1 million people are estimated to have age-related macular degeneration in West Germany. Anatomical aspects of the normal macula and physiological ageing processes in the retina will be discribed including alterations in the choroid, in Bruch's membrane, the pigment epithelium and the sensory retina. Risk factors for the development of age-related macular degeneration are age per se, perhaps ethnologic characteristics, ocular characteristics, and perhaps environmental factors. The histopathology...

关键词： AGE-RELATED MACULAR DEGENERATION CURRENT ASpECTS OF pAThOGENESIS AND TREATMENT AMD

potential hydrodynamic origin of frictional transients in sliding mesothelial tissues

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Friction 2013年第2期1卷 163-177页

作者： Stephen h.LORING James p.BUTLER Department of Anesthesia Critical Care and Pain MedicineBeth Israel Deaconess Medical Center and Harvard Medical SchoolBoston MA 02215USA Department of Medicine Division of Sleep MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBoston MA 02215USA

Steady-state and transient variations in frictional force observed in tribological experiments of mesothelial tissues sliding in lubricant were analyzed with a mathematical model to test the hypothesis that such phenomena are manifestations of elastohydrodynamic lubrication and,importantly,do not require physical contact between the sliding *** model incorporates three phenomena characteristic of elastohydrodynamic lubrication:thinning of the liquid layer between sliding surfaces under a normal load(“squeeze-out”),thickening of the liquid layer due to hydrodynamic pumping,and smoothing of the elastic surfaces caused by hydrodynamic pressure *** in soft mesothelial tissues sliding in lubricant showed variations in steady state friction with velocity,load,and lubricant *** non-steady sliding,the decay rate of frictional transients at the start of rotation varied with velocity,the amplitudes of these transients varied with the preceding periods without rotation,and frictional force varied during sinusoidal *** simulations were qualitatively similar to experimental results,supporting these *** lubricant viscosity increased lubricating layer thickness and lowered friction at low speeds and increased friction at high speeds,supporting hydrodynamic *** conclude that the frictional variations seen with sliding mesothelial tissues are consistent with elastohydrodynamic lubrication without contact between the sliding surfaces.

关键词： pleural space breathing pericardium lubrication model

DYNAMIC COMpACTION OF pURE COppER pOWDER USING pULSED MAGNETIC FORCE

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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 forming

preparation and Antibacterial Activity of Three-component NiFe_2O_4@pANI@Ag Nanocomposite

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Journal of Materials Science & Technology 2014年第7期30卷 656-660页

作者： M.Kooti p.Kharazi h.Motamedi Department of Chemistry Shahid Chamran UniversityAhvaz 61357-43169Iran Department of Biology Shahid Chamran UniversityAhvaz 61357-43169Iran

A new three-component and magnetically responsive NiFe2O4@pANI@Ag nanocomposite has been fabricated by coating of nickel ferrite, NiFe2O4, nanoparticles with polyaniline （pANI） and subsequent immobilization of silver nanoparticles onto the surface of polyaniline shell. The as-prepared nanocomposite has been characterized by X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FT-IR）, scanning electron microscopy （SEM）, and vibrating sample magnetometer （VSM）. The saturation magnetization of the NiFe2O4 core decreases dramatically after coating with polyaniline and silver nanoparticles, however, the nanocomposite NiFe2O4@pANI@Ag can be still separated from solution media through magnetic decantation. The antibacterial activity of the synthesized nanocomposite was studied and compared with those of naked NiFe2O4, NiFe2O4@pANI and some standard antibacterial drugs.

关键词： Antibacterial activity Nanocomposite Core/shell Ferrite Magnetic nanoparticles Silver nanoparticles

Numerical simulation of heavy fuel oil atomization using a pulsed pressure-swirl injector

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Chinese Journal of Chemical Engineering 2021年第4期34卷 61-69页

作者： S.M.A.Najafi p.Mikaniki h.Ghassemi School of Mechanical Engineering Iran University of Science and TechnologyP.O.B.16765-163TehranIran

It is known that increasing the injection pressure reduces the breakup length and the droplet *** pulses,on the other hand,helps to atomize the liquid into finer droplets,similar to airassisted injectors but without altering the airtofuel *** further reduce the droplet size and breakup length,a novel injector type,called''pulsed pressureSwirl"(ppS),is introduced in this work,which is a combination of pressureswirl and ultrasonic pulsed injectors.A pressureswirl atomizer was designed and fabricated specifically for Mazut hFO(heavy Fuel Oil).The droplet formation process and droplet size distribution have been studied experimentally(by shadowgraphy high speed imaging)and numerically(with the opensource VolumeofFluid code Gerris).Changing liquid injection pressure effect on the spray angle and film thickness has been *** simulations have been used to study the primary breakup process and quantify the droplet size distributions,using different injection pulse frequencies and *** numerical results have revealed that the new injector concept successfully produces finer droplets and results in a decrease in the breakup length,especially when applying high pulse frequencies,with no significant changes in the spray angle.

关键词： Spray heavy fuel oil Mazut Atomization pulsed pressure-Swirl Injector