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Influence of 10-(6-plastoquinonyl) decyltriphenylphosphonium on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced hyperglycemia

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World Journal of diabetes 2019年第12期10卷 546-559页

作者： Aleksander A Agarkov Tatyana n Popova Yana G Boltysheva department of Medical Biochemistry and Microbiology Voronezh State University

baCKGROUnd It is known that under conditions of tissue tolerance to insulin,observed during type 2 diabetes mellitus(dM2),there is an increased production of reactive oxygen ***,the free radicals can initiate lipid peroxidation(LPO)in lipoprotein *** concentration of LPO products can influence the state of insulin receptors,repressing their hormone connection activity,which is expressed as a reduction of the glucose consumption by *** is possible that reduction in glucose concentration during administration of 10-(6-plastoquinonyl)decyltriphenylphosphonium(SkQ1)to rats with dM2 may be related to the antioxidant properties of this *** To establish the influence of SkQ1 on free-radical homeostasis in the heart and blood serum of rats with streptozotocin-induced *** To induce hyperglycemia,rats were fed a high-fat diet for 1 mo and then administered two intra-abdominal injections of streptozotocin with a 7-d interval at a 30 mg/kg of animal weight dose with citrate buffer equal to pH ***1 solution was administered intraperitoneally at a 1250 nmol/kg dose per *** samples were taken from control animals,animals with experimental hyperglycemia,rats with streptozotocin-induced glycemia that were administered SkQ1 solution,animals housed under standard vivarium conditions that were administered SkQ1,rats that were administered intraperitoneally citrate buffer equal to pH 4.4 once a week during 2 wk after 1-mo high-fat diet,and animals that were administered intraperitoneally with appropriate amount of solution without SkQ1(98%ethanol diluted eight times with normal saline solution).To determine the intensity of free radical oxidation and total antioxidant activity,we used the biochemiluminescence *** hydratase(AH),superoxide dismutase,and catalase activities were estimated using the Hitachi U-1900 spectrophotometer supplied with *** amount of citrate was determined by means of the natel

关键词： diabetes mellitus Free radical oxidation Antioxidants 10-(6-plastoquinonyl)decyltriphenylphosphonium

All-optical nonlinear chiral ultrafast magnetization dynamics driven by circularly polarized magnetic fields

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High Power Laser Science and Engineering 2023年第6期11卷 154-161页

作者： Luis Sánchez-Tejerina Rodrigo Martín-Hernández Rocío Yanes Luis Plaja Luis López-díaz Carlos Hernández-García Grupo de Investigación en Aplicaciones del Láser y Fotónica Departamento de Física AplicadaUniversidad de SalamancaSalamancaSpain Present address:departamento de Electricidad y Electrónica Universidad de ValladolidValladolidSpain departamento de Física Aplicada Universidad de SalamancaSalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaSalamancaSpain

Ultrafast laser pulses provide unique tools to manipulate magnetization dynamics at femtosecond timescales,where the interaction of the electric field usually dominates over the magnetic *** proposals using structured laser beams have demonstrated the possibility to produce regions where intense oscillating magnetic fields are isolated from the electric *** these conditions,we show that technologically feasible tesla-scale circularly polarized high-frequency magnetic fields induce purely precessional nonlinear magnetization *** fundamental result not only opens an avenue in the study of laser-induced ultrafast magnetization dynamics,but also sustains technological implications as a route to promote all-optical non-thermal magnetization dynamics both at shorter timescales-towards the subfemtosecond regime-and at THz frequencies.

关键词： chiral behavior nonlinear dynamics ultrafast dynamics

AF-net:A Medical image Segmentation network based on Attention Mechanism and Feature Fusion

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Computers, Materials & Continua 2021年第11期69卷 1877-1891页

作者： Guimin Hou Jiaohua Qin Xuyu Xiang Yun Tan neal n.Xiong College of Computer Science and Information Technology Central South University of Forestry&TechnologyChangsha410004China department of Mathematics and Computer Science Northeastern State UniversityTahlequah74464OKUSA

Medical image segmentation is an important application field of computer vision in medical image *** to the close location and high similarity of different organs in medical images,the current segmentation algorithms have problems with mis-segmentation and poor edge *** address these challenges,we propose a medical image segmentation network(AF-net)based on attention mechanism and feature fusion,which can effectively capture global information while focusing the network on the object *** this approach,we add dual attention blocks(dA-block)to the backbone network,which comprises parallel channels and spatial attention branches,to adaptively calibrate and weigh ***,the multi-scale feature fusion block(MFF-block)is proposed to obtain feature maps of different receptive domains and get multi-scale information with less computational ***,to restore the locations and shapes of organs,we adopt the global feature fusion blocks(GFF-block)to fuse high-level and low-level information,which can obtain accurate pixel *** evaluate our method on multiple datasets(the aorta and lungs dataset),and the experimental results achieve 94.0%in mIoU and 96.3%in dICE,showing that our approach performs better than U-net and other state-of-art methods.

关键词： deep learning medical image segmentation feature fusion attention mechanism

Phase-field lattice Boltzmann model for dendrites growing and moving in melt flow

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npj Computational Materials 2019年第1期5卷 140-149页

作者： LászlóRátkai Tamás Pusztai LászlóGránásy Wigner Research Centre for Physics P.O.Box 49H-1525 BudapestHungary Brunel Centre of Advanced Solidification Technology Brunel UniversityUxbridgeMiddlesex UB83PHUK

The phase-field and lattice Boltzmann methods have been combined to simulate the growth of solid particles moving in melt *** handle mobile particles,an overlapping multigrid scheme was developed,in which each individual particle has its own moving grid,with local fields attached to *** this approach we were able to simulate simultaneous binary solidification,solute diffusion,melt flow,solid motion,the effect of gravity,and collision of the *** method has been applied for describing two possible modes of columnar to equiaxed transition in the Al–Ti system.

关键词： solidification moving lattice

Biliary endoscopic sphincterotomy: Techniques and complications

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World Journal of Clinical Cases 2018年第16期6卷 1073-1086页

作者： Ayd?n Seref Kksal Ahmet Tarik Eminler Erkan Parlak department of Gastroenterology Sakarya University School of Medicine department of Gastroenterology Hacettepe University School of Medicine

Biliary endoscopic sphincterotomy(EST) refers to the cutting of the biliary sphincter and intraduodenal segment of the common bile duct following selective cannulation, using a high frequency current applied with a special knife, sphincterotome, inserted into the papilla. EST is either used solely for the treatment of diseases of the papilla of Vater, such as sphincter of Oddi dysfunction or to facilitate subsequent therapeutic biliary interventions, such as stone extraction, stenting, etc. It is a prerequisite for biliary interventions, thus every practitioner who performs endoscopic retrograde cholangiopancreatography needs to know different techniques and the clinical and anatomic parameters related to the efficacy and safety of the procedure. In this manuscript, we will review the indications, contraindications and techniques of biliary EST and the management of its complications.

关键词： Complication Indication Biliary endoscopic sphincterotomy Endoscopic retrograde cholangiopancreatography

Context-dependent insect predation pressure on an avian ectoparasite

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Insect Science 2023年第6期30卷 1784-1797页

作者： Angela Salido Jesús Veiga Joaquín Luis Reyes-López Francisco Valera department of Botany Ecology and Plant PhysiologyUniversity of CórdobaCórdobaSpain departamento de Ecología Funcional y Evolutiva Estación Experimental de ZonasÁridas(EEZA-CSIC)AlmeríaSpain department of Parasitology University of GranadaGranadaSpain MEMEG Department of BiologyLund UniversityLundSweden

Context dependence arises when ecological relationships vary with the conditions under which they are observed. Context dependence of interactions involving parasites is poorly known, even if it is key to understanding host–parasite relationships and food web dynamics. This paper investigates to which extent predation pressure on an avian ectoparasite (Carnus hemapterus) is context-dependent. based on a predator-exclusion experiment, predation pressure on C. hemapterus pupae in the host's nest for 3 years, and its variation between habitat types are quantified. Variation in precipitation and normalized difference vegetation index (ndVI) is also explored as a likely cause of context dependency. We hypothesize that predation pressure should fluctuate with such surrogates of food availability, so that inter-annual and intra-annual differences may emerge. The number of nests with significant reduction of pupae varied widely among years ranging from 24% to 75%. However, average pupae reduction in nests where a significant reduction occurred did not vary between years. no differences in predation rates between habitat types were detected. Precipitation and ndVI varied widely between years and ndVI was consistently lower around nests on cliffs than around nests on trees and farmhouses. Parallels were found between variation in predation pressure and precipitation/ndVI at a wide scale (highest predation the driest year, and much lower the 2 rainier ones), but not at the nest scale. This paper shows clear context-dependent insect predation pressure on an ectoparasite under natural conditions, and that such interaction changes in signs rather than magnitude between years. The causes for these variations require longer-term studies and/or well-designed, large-scale experiments.

关键词： ants arid areas Carnus hemapterus consumer-resource interaction ecosys-tem productivity predator-parasite rainfall

Immunoprophylactic potential of filarial glutathione-s-transferase in lymphatic filariaisis

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Asian Pacific Journal of Tropical Medicine 2011年第3期4卷 185-191页

作者： Madhusmita bal Mandal n Achary KG das MK Kar SK division of Immunology Regional Medical Research Centre(Indian Council of Medical Research) ChandrasekharpurBhubaneswar-751023India

Objective:To elucidates the immunoprophylactic potential of glutathion-s-transferase(GST) from cattle filarial parasite Setaria digitata(***) against lymphatic ***: GST was purified through affinity chromatography(SdGST) and chacterized by SdS-PAGE and nano-LC MS/MS *** isotypes to SdGST were measured by *** dependant cellular cytotoxicity(AdCC) was performed in vitro using sera from immunized animals and immune individuals.T-cell proliferation and cytokine response to SdGST in different groups of filariasis were *** potential of SdGST was evaluate in animal ***:SdGST exhibited 30-fold enhancement of enzyme activity over crude parasitic *** was found to be 26 kda by *** LC-MS/MS analysis followed by blast search showed 100%homology with dirqfilaria immitis(***) and only 43%with Homo sapiens(***).Immunoblotting analysis showed putatively immune individuals carry significant level of antibodies to SdGST as compared with *** sera and sera endemic normal could neutralize the enzymatic activity of SdGST and inducing in vitro cytotoxicity of *** blood mononuclear cells(PBMC) from endemic normals upon stimulation with SdGST showed a mixed type of Th1/Th2 *** immunization clear microfilariae from circulation in *** implanted ***:The heterologous GST could be potentially developed as a vaccine candidate against lymphatic filarial parasite.

关键词： Glutathione-s-transferase Setaria digitata Lymphatic filariasis

Vickers and Knoop Micro-hardness Behavior of Coarse-and Ultrafine-grained Titanium

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Journal of Materials Science & Technology 2010年第10期26卷 904-907页

作者： K.P.Sanosh A.balakrishnan L.Francis T.n.Kim department of Information and Electronic Materials Engineering College of EngineeringPaichai University Laboratoire SimaP GPM2 Grenoble-INPUJFCNRS 101 Rue de la PhysiqueBP46 38402 Saint Martin d'He' res CedexFrance University of Genova Department of Chemistry and Industrial Chemistry

The present study focuses on the relationship of hardness with grain size for commercially pure titanium （CpTi） and ultra fine grained titanium （UFG-Ti） produced by equal channel angular process （ECAP） of Cp-Ti）.Vickers and Knoop indentations of UFG-Ti at different loads was ～2.5 times harder than those of *** diffraction （XRd） analysis showed peak broadening in UFG-Ti due to reduced grain size and micro-lattice *** electron microscopy （SEM） revealed that ECAP had reduced the grain size of Cp-Ti by ～10 *** statistics showed UFG-Ti with lower dispersion in hardness values compare to Cp-Ti indicating a more uniform microstructure.

关键词： Vickers Knoop Hardness Ultrafine-grained Titanium

Optimization of Gas Sensing Performance of nanocrystalline SnO_2 Thin Films Synthesized by Magnetron Sputtering

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Chinese Physics Letters 2016年第6期33卷 99-103页

作者： n.Panahi M.T.Hosseinnejad M.Shirazi M.Ghoranneviss department of Physics Bandar Abbas BranchIslamic Azad University Young Researchers and Elite Club Science and Research BranchIslamic Azad University Plasma Physics Research Center Science and Research BranchIslamic Azad University

Tin oxide （SnO2） is one of the most promising transparent conducting oxide materials, which is widely used in thin film gas sensors. We investigate the dependence of the deposition time on structural, morphologicaJ and hydrogen gas sensing properties of SnO2 thin films synthesized by dc magnetron sputtering. The deposited samples are characterized by XRd, SEM, AFM, surface area measurements and surface profiler. Also the H2 gas sensing properties of SnO2 deposited samples are performed against a wide range of operating temperature. The XRd analysis demonstrates that the degree of crystallinity of the deposited SnO2 films strongly depends on the deposition time. SEM and AFM analyses reveal that the size of nanoparticles or agglomerates, and both average and rms surface roughness is enhanced with the increasing deposition time. Also gas sensors based on these SnO2 nanolayers show an acceptable response to hydrogen at various operating temperatures.

关键词： of on as it or in Optimization of Gas Sensing Performance of nanocrystalline SnO2 Thin Films Synthesized by Magnetron Sputtering SnO by