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Transactions of Nonferrous Metals Society of china 2010年第10期20卷 1822-1828页

作者： P.VENKATAcHALAM S.ramesh KUMAR B.RAVISANKAR V.THOMAS PAUL M.VIJAYALAKSHMI Department of Metallurgical and Materials Engineering National Institute of Technology Physical Metallurgy Division IGCAR

Al-cu alloy was deformed through equal channel angular pressing(EcAP) by routes A,Ba,Bc and c up to 5 *** was done using a 90° die for three different conditions,namely 1) as received,2) solutionised at 768 K for 1 h and 3) solutionised at 768 K for 1 h + aged at 468 K for 5 *** microstructure,microhardness and tensile strength were studied for all the three conditions and four *** improvement in hardness(HV 184 after five passes) and strength(602 MPa after three passes) was observed in solutionised and aged 2014 Al alloy deformed through route *** evolution was reasonably equiaxed in route Bc with aspect ratio of *** and aged 2014 Al alloy deformed through route Bc was identified to have better microstructure and mechanical property than the other processing routes and conditions.

关键词： EcAP processing route 2014 aluminium alloy

Toxic Potential of Palytoxin

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2015年第5期35卷 773-780页

作者： Ji?í PATOcKA ramesh c.GUPTA 吴庆华 Kamil KUcA University of South Bohemia ceske Budejovice Faculty of Health and Social StudiesDepartment of Radiology and Toxicology Biomedical Research center University Hospital Toxicology Department Murray State University college of Life Science Yangtze University Faculty of Informatics and Management University of Hradec Kralove

This review briefly describes the origin,chemistry,molecular mechanism of action,pharmacology,toxicology,and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagellates. Palytoxin is also produced by Zoanthids（i.e. Palythoa）,and cyanobacteria（Trichodesmium）. Palytoxin is a very large,non-proteinaceous molecule with a complex chemical structure having both lipophilic and hydrophilic moieties. Palytoxin is one of the most potent marine toxins with an LD50 of 150 ng/kg body weight in mice exposed intravenously. Pharmacological and electrophysiological studies have demonstrated that palytoxin acts as a hemolysin and alters the function of excitable cells through multiple mechanisms of action. Palytoxin selectively binds to Na＋/K＋-ATPase with a Kd of 20 p M and transforms the pump into a channel permeable to monovalent cations with a single-channel conductance of 10 p S. This mechanism of action could have multiple effects on cells. Evaluation of palytoxin toxicity using various animal models revealed that palytoxin is an extremely potent neurotoxin following an intravenous,intraperitoneal,intramuscular,subcutaneous or intratracheal route of exposure. Palytoxin also causes non-lethal,yet serious toxic effects following dermal or ocular exposure. Most incidents of palytoxin poisoning have manifested after oral intake of contaminated seafood. Poisonings in humans have also been noted after inhalation,cutaneous/systemic exposures with direct contact of aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing cnidarian zoanthids. Palytoxin has a strong potential for toxicity in humans and animals,and currently this toxin is of great concern worldwide.

关键词： dermal extremely subcutaneous analogues noted intravenous intramuscular potent intake hydrophilic

corrosion behavior of as-cast Mg–8Li–3Al+xce alloy in 3.5wt% Nacl solution

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International Journal of Minerals,Metallurgy and Materials 2016年第10期23卷 1196-1203页

作者： S.Manivannan P.Dinesh R.Mahemaa Nandhakumaran MariyaPillai S.P.Kumaresh Babu srinivasan Sundarrajan Department of Metallurgical and Materials Engineering National Institute of Technology Tirchirappalli 620015 Tamil Nadu India TVS Sundaram-clayton Limited Chennai 600050 Tamil Nadu India

Mg-8Li-3Al＋xce alloys（x = 0.5wt%, 1.0wt%, and 1.5wt%） were prepared through a casting route in an electric resistance furnace under a controlled atmosphere. The cast alloys were characterized by X-ray diffraction, optical microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The corrosion behavior of the as-cast Mg-8Li-3Al＋xce alloys were studied under salt spray tests in 3.5wt% Nac l solution at 35°c, in accordance with standard ASTM B-117, in conjunction with potentiodynamic polarization（PDP） tests. The results show that the addition of ce to Mg-8Li-3Al（LA83） alloy results in the formation of Al_2ce intermetallic phase, refines both the α-Mg phase and the Mg_（17）Al_（12） intermetallic phase, and then increases the microhardness of the alloys. The results of PDP and salt spray tests reveal that an increase in ce content to 1.5wt% decreases the corrosion rate. The best corrosion resistance is observed for the LA83 alloy sample with 1.0wt% ce.

关键词： magnesium lithium alloys cerium sodium chloride solutions corrosion rate polarization

Mechanisms of triglyceride metabolism in patients with bile acid diarrhea

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World Journal of Gastroenterology 2016年第30期22卷 6757-6763页

作者： Nidhi Midhu Sagar Michael McFarlane chuka Nwokolo Karna Dev Bardhan ramesh Pulendran Arasaradnam School of Medicine University of Warwick Coventry CV4 7AL United Kingdom Department of Gastroenterology University Hospitals Coventry and Warwickshire Coventry CV2 2DX United Kingdom Department of Gastroenterology Rotherham General Hospital NHS Trust Rotherham S60 2UD United Kingdom clinical Sciences Research Institute University of Warwick Coventry CV2 2DX United Kingdom

Bile acids(BAs) are essential for the absorption of lipids. BA synthesis is inhibited through intestinal farnesoid X receptor(FXR) activity. BA sequestration is known to influence BA metabolism and control serum lipid concentrations. Animal data has demonstrated a regulatory role for the FXR in triglyceride metabolism. FXR inhibits hepatic lipogenesis by inhibiting the expression of sterol regulatory element binding protein 1c via small heterodimer primer activity. conversely, FXR promotes free fatty acids oxidation by inducing the expression of peroxisome proliferator-activated receptor α. FXR can reduce the expression of microsomal triglyceride transfer protein, which regulates the assembly of very low-density lipoproteins(VLDL). FXR activation in turn promotes the clearance of circulating triglycerides by inducing apolipoprotein c-Ⅱ, very low-density lipoproteins receptor(VLDL-R) and the expression of Syndecan-1 together with the repression of apolipoprotein c-Ⅲ, which increases lipoprotein lipase activity. There is currently minimal clinical data on triglyceride metabolism in patients with bile acid diarrhoea(BAD). Emerging data suggests that a third of patients with BAD have hypertriglyceridemia. Further research is required to establish the risk of hypertriglyceridaemia in patients with BAD and elicit the mechanisms behind this, allowing for targeted treatment.

关键词： Bile acids Bile acid diarrhea Triglycerides Farnesoid X receptor

SNcDM: Spinal Tumor Detection from MRI Images Using Optimized Super-Pixel Segmentation

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Intelligent Automation & Soft computing 2023年第5期36卷 1899-1913页

作者： T.Merlin Inbamalar Dhandapani Samiappan R.ramesh Department of Electronics and Instrumentation Engineering Saveetha Engineering CollegeChennaiTamilnaduIndia Department of Electronics and communication Engineering Saveetha Engineering CollegeChennaiTamilnaduIndia Department of Electronics and communication Engineering Tagore Engineering CollegeChennaiTamilnaduIndia

conferring to the American Association of Neurological Surgeons(AANS)survey,85%to 99%of people are affected by spinal cord *** symptoms are varied depending on the tumor’s location and ***-to-the-min-ute,back pain is one of the essential symptoms,but it does not have a speciﬁc symptom to recognize at the earlier *** signiﬁcant research studies have been conducted to improve spine tumor recognition ***,the traditional systems are consuming high time to extract the speciﬁc region and *** identiﬁcation of the tumor region affects the predictive tumor rate and causes the maximum error-classiﬁcation ***,in this work,Super-pixel analytics Numerical characteristics Disintegration Model(SNcDM)is used to segment the tumor affected *** the super-pix-els of the affected region by this method reduces the variance between the iden-tiﬁed ***,the super-pixels are selected according to the optimized convolution network that effectively extracts the vertebral super-pixels *** super-pixels improve the network learning and training process,which minimizes the maximum error classiﬁcation problem also the efﬁciency of the system was evaluated using experimental results and analysis.

关键词： Maximum error-classiﬁcation problem optimized convolution network super-pixel analytics numerical characteristics disintegration model(SNcDM)

Effectiveness of massage therapy on post-operative outcomes among patients undergoing cardiac surgery:A systematic review

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International Journal of Nursing Sciences 2015年第3期2卷 304-312页

作者： c.ramesh Vasudev Baburaya Pai Nitin Patil Baby S.Nayak Anice George Linu Sara George Elsa Sanatombi Devi Manipal college of Nursing Manipal UniversityManipalIndia Kasturba Medical college Manipal UniversityManipalIndia

The incidence and prevalence of cardiovascular disease(cVD)are increasing rapidly in developing *** patients with cVD do not respond to medical treatment and have to undergo cardiac *** highly stressful experience results in increased levels of anxiety for *** objective of this review was to evaluate the efficacy of massage therapy on postoperative outcomes among patients undergoing cardiac surgery.A comprehensive literature search was made on PubMed-Medline,cINAHL,Science Direct,Scopus,Web of Science and the cochrane library databases for original research articles published between 2000 and *** articles that reported the efficacy of massage therapy in patients undergoing cardiac surgery were *** cochrane data extraction form was used to extract data.A total of 297 studies were identified in the literature ***,only seven studies were eligible for *** the seven studies,six studies demonstrated the effects of massage therapy on improving postoperative outcomes of patients,while one study found no evidence of *** the methods varied considerably,most of the studies included in this review reported positive ***,there is some evidence that massage therapy can lead to positive postoperative *** of the effectiveness of massage therapy in patients undergoing cardiac surgery remains *** research is needed to provide a strong evidence base for the use of massage therapy to improve post-operative outcomes and recovery among cardiac surgery patients.

关键词： Anxiety Heart surgery Massage Pain Post-operative period

Microstructure and dry sliding wear behavior of cu-Sn alloy reinforced with multiwalled carbon nanotubes

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Transactions of Nonferrous Metals Society of china 2016年第7期26卷 1755-1764页

作者： H.M.MALLIKARJUNA K.T.KASHYAP P.G.KOPPAD c.S.ramesh R.KESHAVAMURTHY Advanced composites Research centre (AcRc) P E S Institute of Technology Department of Mechanical Engineering GEC Department of Mechanical Engineering Atria Institute of Technology Research and Development Rapsri Engineering Products Company Ltd. Department of Mechanical Engineering Alliance College of Engineering and Design Alliance University Department of Mechanical Engineering Dayananda Sagar College of Engineering

Multiwalled carbon nanotubes （MWcNTs） reinforced cu-Sn alloy based nanocomposite was developed by powder metallurgy route. The mass fraction of cNTs was varied from 0 to 2% in a step of 0.5%. The developed nanocomposites were subjected to density, hardness, electrical conductivity, and friction and wear tests. The results reveal that the density of nanocomposite decreases with the increase of the mass fraction of cNTs. A significant improvement in the hardness is noticed in the nanocomposite with the addition of cNTs. The developed nanocomposites show low coefficient of friction and improved wear resistance when compared with unreinforced alloy. At an applied load of 5 N, the coefficient of friction and wear loss of 2%cNTs reinforced cu-Sn alloy nanocomposite decrease by 72% and 68%, respectively, compared with those of cu-Sn alloy. The wear mechanisms of worn surfaces of the composites are reported. In addition, the electrical conductivity reduces with the increase of the content of cNTs.

关键词： cu-Sn alloy carbon nanotube nanocomposites powder metallurgy microstructure sliding wear

Fluorine Doping Effect in the New Superconducting Y3Ba5cu8Oycompound

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Journal of Minerals and Materials characterization and Engineering 2011年第14期10卷 1277-1283页

作者： K. srinivasan George Thomas c. P. Padaikathan Department of Materials Engineering Indian Institute of ScienceBangalore – 560 012 India Department of Physics Christ University Bangalore – 560 029 India Department of Physics Govt. First Grade College K. R. PuramBangalore – 560 036 India

The newly identified yttrium based high critical temperature (Tc) superconductor of composition Y3Ba5cu8Oy (Y358) and the fluorine doped Y3Ba5cu8Oy-0.2F0.2 (Y358+F) compounds were synthesized by solid state reaction technique. The micro structural and morphological features of the synthesized samples were investigated by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive Spectrum (EDS) analysis. The XRD of the samples revealed a structure similar to Y1Ba2cu3Oy-o(Y123) compound with about three fold larger ‘c’ axis. The SEM image of the fluorine doped sample (Y358+F) showed a needle like inter growth which was different from that of pure (Y358) sample. The Tc of the sample, measured by self inductance method showed an onset of superconductivity at 92 K for the pure and 98 K for the fluorine doped sample. On further heating the fluorinated sample for 24 hours, the needle like intergrowth had disappeared as seen from SEM micrograph and the Tc onset of the sample had increased to 110 K with a two step transition.

关键词： High Tc superconductor solid state reaction XRD SEM Tc measurement fluorine doping.

Numerical simulation and experiment of error field measurement using luminous trace of electron beam in SST-1

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Plasma Science and Technology 2019年第10期21卷 9-16页

作者： Someswar DUTTA Y PARAVASTU J DHONGDE H cHUDASMA S GEORGE K DHANANI A MAKWANA c DODIYA P VARMORA D K SHARMA A K SINGH U KUMAR D RAVAL U PRASAD Z KHAN R srinivasan D RAJU Institute for Plasma Research GandhinagarGujrat 382428India Homi Bhabha National Institute (HBNI) AnushaktinagarMumbai 400094India

In contrast to the earlier experiments conducted in other machines, here, in SST-1 the error field measurement experiment is performed with a filled gas pressure ~8×10^-4 mbar which helped to create a luminescent toroidal beam of electron path originated due to impact excitation and guided by the toroidal magnetic field. Beam path deviations are observed and recorded from radial and top ports using visible range cameras. Such creation and detection of the electron beam path differs from the earlier works where the gun emitted electron beam deviation in ultrahigh vacuum was detected on a collector-grid/fluorescent screen. In the present experiment, large beam deviations were observed. Later investigation of the experimental set-up reveals existence of a possible source of radial electric field in between the source and the vacuum vessel which are separately grounded. Thus, to understand the observed phenomena, experiments are numerically modeled with deviated TF coil set, PF coil set and the electron source location. A particle tracing code is used to follow the electron path in the magnetic field generated by the coil set of interest. Simulation results suggest that the large deviation corresponds to the E×B drifts and not due to the large field errors. Toroidally averaged field errors of the SST-1 TF coils at toroidal field of B0?=?15 kG are negligibly small ~B0?×?10^-6 or less, which should not adversely affect the plasma performance.

关键词： electron beam error field SST-1 TF coil

Mechanical properties and stress corrosion cracking behaviour of AZ31 magnesium alloy laser weldments

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Transactions of Nonferrous Metals Society of china 2011年第1期21卷 1-8页

作者： P.B.srinivasan S.RIEKEHR c.BLAWERT W.DIETZEL M.KO AK Institute of Materials Research GKSS-Forschungszentrum Geesthacht GmbH Geesthacht D-21502Germany

An AZ31 HP magnesium alloy was laser beam welded in autogenous mode with AZ61 filler using Nd-YAG laser *** examination revealed that the laser beam weld metals obtained with or without filler material had an average grain size of about 12 μ*** microhardness and the tensile strength of the weldments were similar to those of the parent ***,the stress corrosion cracking （Scc） behaviour of both the weldments assessed by slow strain rate tensile （SSRT） tests in ASTM D1384 solution was found to be slightly inferior to that of the parent *** was observed that the stress corrosion cracks originated in the weld metal and propagated through the weld metal-HAZ regions in the autogenous *** the other hand,in the weldment obtained with AZ61 filler material,the crack initiation and propagation was in the HAZ *** localized damage of the magnesium hydroxide/oxide film formed on the surface of the specimens due to the exposure to the corrosive environment during the SSRT tests was found to be responsible for the Scc.

关键词： AZ31 magnesium alloy laser welding microstructure mechanical properties slow strain rate tensile test stress corrosion cracking fractography