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Journal of materials Science & Technology 2014年第1期30卷 13-18页

作者： S.Sudhahar m.Krishna Kumar v.Jayaramakrishnan r.muralidharan r.mohan Kumar Department of Physics Presidency College Department of Physics P.S.G.College of Arts and Science Department of Science and Humanities Vel Tech High Tech Dr.Rangarajan Dr.Sakunthala Engineering College

rare earth Sm＋ ion doped potassium hydrogen phthalate （KHP） single crystal was grown by slow evaporation technique. Single crystal and powder X-ray diffraction analyses confirm the crystalline perfection of Sm＋ ion doped KHP crystal. The functional groups of pure and Sm＋ ion doped KHP crystals were identified by Fourier transform infrared spectroscopy （FTIr） spectral studies. Thermogravimetric and differential thermal analyses were carried out to study the thermal behavior of the grown crystals. Uv-vis studies explored the optical transmittance of the grown crystals in the entire visible region. The mechanical strength and etching studies were performed to assess the perfection of the pure and Sm＋ ion doped KHP crystals. The refractive index and birefringence properties of the grown crystal were analyzed. The second harmonic generation efficiency of Sm＋ ion doped KHP crystals was observed by Kurtz-Perry powder test.

关键词： Crystal growth Potassium hydrogen phthalate (KHP) single crystal Differential thermal analysis FTIr Hardness

Antibacterial HA-coatings on bioresorbable mg alloy

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Journal of magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.v.Nadaraia D.v.mashtalyar m.A.Piatkova A.I.Pleshkova I.m.Imshinetskiy m.S.Gerasimenko E.A.Belov v.v.Kumeiko D.N.Kozyrev K.A.Fomenko v.v.mostovaya B.r.Torpanov A.r.Biktimirov I.S.Osmushko S.L.Sinebryukhov S.v.Gnedenkov Institute of Chemistry FEB rAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far Eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.v.Zhirmunsky National Scientific Center of marine Biology FEB rAS 17 St.PalchevskogoVladivostok 690041Russia regional Clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia NmIC“Treatment and rehabilitation Center” 3 Ivankovskoe highwayMoscow 125367Russia

In this study,a calcium-phosphate coating was formed on a mg-mn-Ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were *** to SEm,EDS,XrD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEO coatings was *** to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility mg alloy Plasma electrolytic oxidation Hydroxyapatite vancomycin

Effects of iron manipulation on trace elements level in a model of colitis in rats

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World Journal of Gastroenterology 2005年第28期11卷 4396-4399页

作者： m Barollo r D'Incà m Scarpa v medici r Cardin m Bortolami C ruffolo I Angriman GC Sturniolo Department of Surgical and Gastroenterological Sciences University of Padua Italy

AIm: Trace elements (TE) metabolism is altered in inflammatory bowel diseases. TE (zinc and copper) are constituents of antioxidant enzymes. Iron is involved in the pathogenesis of chronic inflammation. The aim was to evaluate zinc and copper status and the effects of iron manipulation in experimental ***: Twenty-four male Sprague-Dawley rats were divided into four groups: standard diet, iron-deprived diet,iron-supplemented diet, and sham-treated *** damage was scored. DNA adducts were measured in the colon. Liver and colonic concentration of TE were ***: macroscopic damage was reduced in irondeprived groups and increased in iron-supplemented *** to the DNA was reduced in iron-deprived groups and increased in iron-supplemented groups. Liver and colonic iron concentrations were reduced in iron-deprived and increased in iron-supplemented rats. Liver zinc concentration was reduced after supplementation whereas colonic levels were similar in controls and treated rats. Liver copper concentration was reduced in all the colitic groups except in the iron-supplemented group whereas colonic concentration was increased in iron-deprived ***: Iron deprivation diminishes the severity of DNBS colitis while supplementation worsens colitis. Zinc and copper status are modified by iron manipulation.

关键词： Trace elements Colitis

rilmenidine prevents blood pressure increase in rats with compromised nitric oxide production

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Acta Pharmacologica Sinica 2004年第12期25卷 74-80页

作者： mria GErOv,Jozef TrK,Ol’ga PECHv,Jana mATUKOv Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak republic Institute of Pathophysiology medical School Comenius University Bratislava Slovak republic Now in Center for Blood research and Department of Pathology Harvard medicalSchool Boston USA.

AIm: To search tools of high blood pressure in the model of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilmenidine, agonist of imidazoline receptors, which was suggested to modulate central sympathetic outflow. mETHODS: Three experimental groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine methyl ester (L-NAmE) 40 mg·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of imidazoline receptors rilmenidine 3 mg·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasmeasured weekly noninvasively. At the end of experiment aortic ring isometric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determined. rESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. rilmenidine administered simultaneously with L-NAmE (group II) prevented the increase of blood pressure which did not differ significantly from control values; aortic ring relaxation to acetylcholine did not differ from control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: rilmenidinehas aremarkable role inNO-defective hypertension, possibly by inhibiting central sympathetic outflow and by affecting receptors in vascular smooth muscle also. The prime cause of hypertension in this experimental model - the compromised production of NO due to inhibition of NOS - was not affected by rilmenidine.

关键词： NO deficiency hypertension imidazoline receptor nitric-oxide synthase sympathetic activity

Design of experiments for determination of influence of different parameters on mechanical properties of semi-solid extruded parts

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中国有色金属学会会刊：英文版 2010年第S3期20卷 794-797页

作者： v.POUvAFAr S.A.SADOUGH F.HOSSEINJ m.r.rAHmANI Center of Excellence in Solid mechanics Mechanical Engineering DepartmentAmirKabir University of Technology(Tehran Polytechnic)

Near net-shape production of complex parts with higher mechanical properties is one of the most important final goals of the recent researches on the semi-solid *** the knowledge of the influence of every parameter on the properties of final parts is the key in the production of high quality complex *** these parameters forming temperature and velocity,and reheating and holding times have the greatest effects on the final mechanical properties of the *** influence of the parameters of non-dendritic billet production,forming speed,temperature and holding time on the properties of semi-solid extruded parts were ***-slope method was employed in order to produce non-dendritic *** material used was A356 aluminum *** the number of the parameters influencing the final properties of the parts was high(these parameters include:cooling slope angle,ram velocity,temperature and holding time),the final number of the experiments required would be n4,in which n is the number of the states of the parameters(5 in our case).In order to reduce this amount,design of experiments Tachuchi method was employed(design L25).Using this method the number of required experiments was reduced to *** the experiments the prepared semi-solid samples were extruded under isothermal condition and with 5 different ram *** tensile tests were conducted on the extruded parts and the mechanical properties of the parts were *** obtained results analyzed with miniTab and the influence of each of the parameters and also the percentage of its influence were *** an optimum region for the parameters was *** temperature,ram speed,slope angle and holding time have more important effects descendingly.

关键词： semi-solid extrusion Tachuchi method A356 alloy mechanical properties

Color and behavior differently predict competitive outcomes for divergent stickleback color morphs

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Current Zoology 2018年第1期64卷 115-123页

作者： robin m. TINGHITELLA Whitley r. LEHTO v. Faith LIErHEImEr Department of Biological Sciences University of Denver 2199 S. University Blvd Denver CO 80208 USA

Our knowledge of how male competition contributes to speciation is dominated by investigations of competition between within-species morphs or closely related species that differ in conspicuous traits expressed during the breeding season （e.g. color, song）. In such studies, it is important to consider the manner in which putatively sexually selected traits influence the outcome of competitive interactions within and between types because these traits can communicate information about competitor quality and may not be utilized by homotypic and heterotypic receivers in the same way. We studied the roles of breeding color and aggressive behaviors in competition within and between two divergent threes- pine stickleback Gasterosteus aculeatus color types. Our previous work in this system showed that the switch from red to black breeding coloration is associated with changes in male competition biases. Here, we find that red and black males also use different currencies in competition. Winners of both color types performed more aggressive behaviors than losers, regardless of whether the competitor was of the same or opposite color type. But breeding color differently predicted competitive outcomes for red and black males. males who were redder at the start of competition were more likely to win when paired with homotypic competitors and less likely to win when paired with heterotypic competitors. In contrast, black color, though expressed in the breeding season and condition dependent, was unrelated to competitive outcomes. Placing questions about the role of male competition in speciation in a sexual signal evolution framework may provide insight into the ＂why and how＂ of aggression biases and asymmetries in competitive ability between closely related morphs and species.

关键词： male competition speciation sexual signal color threespine stickleback Gasterosteus aculeatus

The Analysis of the Fusion reaction of Two Colliding Nuclei Using the FCC Lattice model

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Chinese Physics Letters 2013年第10期30卷 63-67页

作者： m.Golshanian O.N.Ghodsi r.Gharaei v.Zanganeh Department of Physics Sciences FacultyUniversity of MazandaranP.O.Box 47415-416BabolsarIran Department of Physics Sciences FacultyGolestan UniversityP.O.Box 49138-15759GorganIran

The complete fusion channel of two approaching nuclei,including the interaction potential and fusion cross section,is systematically analyzed using the face-center-cubic(FCC)*** this purpose,we assume that the initial distribution of the nucleons in target and projectile nuclei is formed based on the FCC lattice ***,the density-dependent nucleon-nucleon interaction(CDm3Y6)is employed to parameterize the nuclear interactions between the participant *** obtained results for 45 fusion reactions reveal that the FCC+CDm3Y6 model is able to reproduce the corresponding experimental data of the barrier heights and positions within±10%,on *** analytical calculations of the fusion cross section are performed by employing the coupled-channel approach which includes couplings to the low-lying2^(+) and 3^(-) states in target and projectile *** is shown that the theoretical values of the fusion excitation functions based on the selected microscopic framework are consistent with the experimental data.

关键词： interaction assume approaching

Focus on the gut-brain axis: multiple sclerosis, the intestinal barrier and the microbiome

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World Journal of Gastroenterology 2018年第37期24卷 4217-4223页

作者： Carlos r Camara-Lemarroy Luanne m metz v Wee Yong Department of Clinical Neurosciences Cumming School of Medicine University of Calgary Hotchkiss Brain Institute Cumming School of Medicine University of Calgary

The brain-gut axis serves as the bidirectional connection between the gut microbiome, the intestinal barrier and the immune system that might be relevant for the pathophysiology of inflammatory demyelinating diseases. People with multiple sclerosis have been shown to have an altered microbiome, increased intestinal permeability and changes in bile acid metabolism. Experimental evidence suggests that these changes can lead to profound alterations of peripheral and central nervous system immune regulation. Besides being of pathophysiological interest, the brain-gut axis could also open new avenues of therapeutic targets. modification of the microbiome, the use of probiotics, fecal microbiota transplantation, supplementation with bile acids and intestinal barrier enhancers are all promising candidates. Hopefully, pre-clinical studies and clinical trials will soon yield significant results.

关键词： multiple sclerosis microbiome Intestinal barrier Bile acids Gut-brain axis

PrOPErTIES, WELDABILITY AND APPLICATIONS OF ADvANCED WrOUGHT SUPErALLOYS FOr GAS TUrBINE ENGINES

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Acta metallurgica Sinica(English Letters) 2005年第1期18卷 1-14页

作者： D.L. Klarstrom v.r. Ishwar m.D. rowe Haynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USA

Alloy selection and alloy design both require consideration of an array of material attributes, including in-service properties, weldability and fabricability. Critical properties of advanced wrought superalloys for gas turbine applications include high temperature strength, thermal stability, oxidation resistance and fatigue resistance. In this paper, the properties of twelve wrought solid-solution-strengthened and six age-hardenable superalloys are compared. Weldability is an important attribute and can be a major limiting factor in the use of certain alloys. Weldability test methods are discussed and the resistance of alloys to solidification cracking and strain-age cracking is compared. The use of weldability testing in the development of modern wrought su-peralloys is discussed with several examples cited. Finally, alloy selection for gas turbine components is outlined, taking into account both alloy properties and fabricability.

关键词： wrought superalloys mechanical properties strain-age cracking of weldments selection and application of wrought superalloys

Simulation of detection and scattering of sound waves by the lateral line of a fish

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Chinese Physics B 2022年第2期31卷 398-404页

作者： v m Adamyan I Y Popov I v Blinova v v Zavalniuk Odessa I.I.mechnikov National University Dvoryanskaya Str.2Odesa65082Ukraine ITmO University Kronverkskiy49Saint Petersburg197101Russia Odessa military Academy 10 Fontanska RoadOdesa 65009Ukraine

A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is *** the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound *** strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming.

关键词： acoustic equation point self-adjoint perturbations of Laplace operator scattering lateral line