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Epidural electrical stimulation for spinal cord injury

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Neural Regeneration Research 2021年第12期16卷 2367-2375页

作者： Elliot H.Choi Sandra Gattas Nolan J.Brown John D.Hong Joshua N.Limbo Alvin y.Chan Michael y.oh Department of Pharmacology School of MedicineCase Western Reserve UniversityClevelandOHUSA Department of Ophthalmology Gavin Herbert Eye InstituteSchool of MedicineUniversity of CaliforniaIrvineCAUSA Department of Neurosurgery University of CaliforniaIrvineCAUSA

A long-standing goal of spinal cord injury research is to develop effective repair strategies,which can restore motor and sensory functions to near-normal *** advances in clinical management of spinal cord injury have significantly improved the prognosis,survival rate and quality of life in patients with spinal cord *** addition,a significant progress in basic science research has unraveled the underlying cellular and molecular events of spinal cord *** efforts enabled the development of pharmacologic agents,biomaterials and stem-cell based *** these efforts,there is still no standard care to regenerate axons or restore function of silent axons in the injured spinal *** challenges led to an increased focus on another therapeutic approach,namely *** multiple animal models of spinal cord injury,epidural electrical stimulation of the spinal cord has demonstrated a recovery of motor *** evidence regarding the efficacy of epidural electrical stimulation has further expanded the potential of epidural electrical stimulation for treating patients with spinal cord ***,most clinical studies were conducted on a very small number of patients with a wide range of spinal cord ***,subsequent studies are essential to evaluate the therapeutic potential of epidural electrical stimulation for spinal cord injury and to optimize stimulation ***,we discuss cellular and molecular events that continue to damage the injured spinal cord and impede neurological recovery following spinal cord *** also discuss and summarize the animal and human studies that evaluated epidural electrical stimulation in spinal cord injury.

关键词： central nervous system chondroitin sulfate proteoglycans epidural electrical stimulation glial scar gliosis neural activity neuromodulation oligodendrocyte spinal cord injury

Recent progress on the study of asymmetric vortex flow over slender bodies

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Acta Mechanica Sinica 2008年第5期24卷 475-487页

作者： X.y.Deng W.Tian B.F.Ma y.k.Wang key Laboratory of Fluid Mechanics Ministry of EducationBeihang University100083 BeijingChina

The investigations of forebody vortex flow and its flow control have great importance in both academic field and engineering application areas. A large number of papers and many review papers have been published. However in this research field of forebody asymmetric vortices, three problems such as tip perturbation effect, Reynolds number effect and flow instability are less studied and thus not understood completely. So many researches are still working on the issues in recent years. The present paper attempts to provide a review of recent research progress on first two problems. The first problem is mainly concerned with how the vortex flow evolves after tip perturbation; how to solve the problem of repeatability and reproducibility of wind tunnel testing data; how to develop a conception of active flow control technique with tip perturbation based on the study of vortex flow response to tip perturbation. For the second problem one is mainly concerned that how the asymmetric vortices are developed with the increase of Reynolds number; how to classify the vortex flow patterns in different Reynolds number regimes; how to develop an appropriate boundary layer transition technique to simulate flows at high Reynolds number in the convention wind tunnels. Finally, some important ques- tions that deserve answers are proposed in the concluding remarks.

关键词： High angle of attack aerodynamics ,Asymmetric vortex Tip perturbation Slender body ,Reynolds number effect

Grain refinement mechanism of Mg-3Sn-1Mn-1La alloy during accumulative hot rolling

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Journal of Materials Science & Technology 2021年第32期91卷 251-261页

作者： Z.y.Zhao R.G.Guan y.F.Shen P.k.Bai School of Materials Science and Engineering North University of ChinaTaiyuan 030051China bEngineering Research Center of Continuous Extrusion Ministry of EducationDalian Jiaotong UniversityDalian 116028China key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang 110004China

We elucidate the effect of lanthanum(La) on the grain refinement of Mg-3 Sn-1 Mn alloy during accumulative hot rolling. The lath-shaped Mg_(2) Sn phase in the Mg-3 Sn-1 Mn alloy is firstly broken and spheroidized,and then the size increases and coarsens with the increase of rolling reduction, most of Mg_(2) Sn move from grain boundary to grain and are homogeneously distributed within the matrix. However, the plate-shaped Mg Sn La compound in Mg-3 Sn-1 Mn-1 La gradually becomes fine, spheroidized, and homogeneously distributed. The grain sizes of Mg-3 Sn-1 Mn and Mg-3 Sn-1 Mn-1 La alloys become fine through dynamic recrystallization(DRX), though the grain refinement of Mg-3 Sn-1 Mn-1 La alloy is better compared to the Mg-3 Sn-1 Mn alloy. A large number of uniformly distributed spherical Mg Sn La compounds pin the dislocations, thus increasing the dislocation density. Hence, the driving force for DRX increases and promotes the formation of deformation bands and more twins, providing the sites for DRX nucleation and growth.

关键词： Mg alloy Grain refinement Dynamic recrystallization Accumulative hot rolling

Statistical modeling and optimization of a multistage gas-solid fluidized bed for removing pollutants from flue gases

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Particuology 2015年第5期13卷 72-81页

作者： k.Mahalik y.k.Mohanty k.C.Biswal G.k.Roy J.N.Sahu Department of Chemical Engineering Gandhi Institute of Engineering and Technology Department of Chemical Engineering National Institute of Technology Department of Chemical Engineering Faculty of EngineeringUniversity of Malaya Petroleum and Chemical Engineering Programme Area Faculty of EngineeringInstitut Teknologi Brunei(A Technology University)

The present paper describes the statistical modeling and optimization of a multistage gas-solid fluidized bed reactor for the control of hazardous pollutants in flue gas. In this work, we study the hydrodynamics of the pressure drop and minimum fluidization velocity. The hydrodynamics of a three-stage fluidized bed are then compared with those for a single-stage unit. It is observed that the total pressure drop over all stages of the three-stage fluidized bed is less than that of an identical single-stage system. However, the minimum fluidization velocity is higher in the single-stage unit. Under identical conditions, the minimum fluidization velocity is highest in the top bed, and lowest in the bottom bed. This signifies that the behavior of solids changes from a well-mixed flow to a plug-flow, with intermediate behavior in the middle bed.

关键词： Fluidized bed Multi-stage Pressure drop Minimum fluidization velocity Optimization

Cocos nucifera *** as green corrosion inhibitor for acid corrosion of aluminium in HCl solution

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Chinese Chemical Letters 2010年第12期21卷 1449-1452页

作者： Olusegun k.Abiola y.Tobun Department of Chemistry Federal University of Petroleum ResourcesEffurunNigeria Department of Chemistry University of LagosAkokaLagosNigeria

The ability of Cocos nucifera ***（CW） as non-toxic corrosion inhibitor for acid corrosion of aluminium in 0.5 mol/L HCl has been studied using chemical *** shows significant inhibition as corrosion inhibitor,with 93%efficiency at the highest concentration of the *** inhibitive action is attributed to the adsorption of the inhibitor molecules on metal surface following Langmuir adsorption isotherm.

关键词： Cocos nucifera L. water Acid inhibition Green inhibitor Aluminium Weight loss

SyNTHESIS AND MICROSTRUCTURE OF SUPERHARD TiN/SiN_x MULTILAyER THIN FILMS

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 242-248页

作者： Z.F.Zhou y.G.Shen y.W.Mai k.y.Li AdvancedCoatingsAppliedResearchLaboratory（ACARL） DepartmentofManufacturingEngineeringandEngineeringManagementCityUniversityofHongKongKowloonHongKongChina CentreforAdvancedMaterialsTechnology（CAMT） SchoolofAerospaceMechanicalandElectronicEngineeringUniversityofSydneySydneyNSW2006Australia

Multilayer thin films of TiN/SiNx have been deposited onto heated Si 100 substra tes (200℃) by reactive dc-magnetron sputtering from Ti and Si targets in an Ar- N2 gas mixture. The rotation speed of the substrate holder was varied from 1 to 20rpm, while target currents were held constant, to produce bilayer periods vary ing from approximately 22 to 0.6nm. These multilayer films were characterized by atomic force microscopy (AFM), cross-sectional transmission electron microscopy (TEM), scanning electron microscopy (SEM), and microhardness measurements. TEM and SEM studies showed elimination of columnar structure in TiN, owing to the in corporation of amorphous SiNx layers. The crystallinity of TiN and amorphous nat ure of SiNx were confirmed by high resolution TEM. An optimum rotation speed was observed, at which hardness was a maximum. The resulting bilayer period was fou nd to be approximately 1.6nm, which resulted in a significant improvement in mic rohardness (~57GPa). The rms surface roughness for this film was less than 1.5nm .

关键词： multilayers hardness supermodulu s stress TiN/SiNx

GAMMA TITANIUM ALUMINIDE ALLOy TECHNOLOGy:STATUS AND FUTURE

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 334-339页

作者： y W.kim UES,Inc.,oh, USA

Gam matitanium aluminide ( γ TiAl) alloys are emerging as a revolutionary engineeringmaterialsfor hightemperaturestructuralapplications. Onthebasisoftheinformation avail ablein the public domain, this paper discussesthe historical background,status and future prospect of gam maalloytechnologyintheareasofalloy development/ design,processdevelop ment, and applications.

关键词： JOM USA PA TMS FUTURE GAMMA TITANIUM ALUMINIDE ALLOy TECHNOLOGy

kinetics of Al Evaporation from Liquid U-Al Alloys in Vacuum Induction Melting

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Journal of Materials Science & Technology 2015年第4期31卷 423-426页

作者： y.J.Duan B.Chen y.C.Ma k.Liu Materials for Special Environment Division Institute of Metal ResearchChinese Academy of Sciences

A research on kinetics of Al evaporation from liquid U—Al alloys was made in a vacuum induction melting（VIM） furnace at 1673—1843 *** evaporation rate of Al was found to be first order with respect to Al content in the *** overall mass transfer coefficient of Al was determined and it was found that the evaporation rate of Al increased with increasing *** apparent activation energy of Al evaporation at 1673-1843 k was 171.5 kJ *** value of mass transfer coefficient of Al in the liquid phase was estimated to be 3.77 × 10-6,7.41×10-6,and 9.40 × 10-6m s-1at 1673,1753,and 1843 k,***,rate determining steps were discussed and it was concluded that the evaporation rate of Al is mainly controlled by liquid phase mass transfer.

关键词： Al evaporation kinetics Liquid U-Al alloys Mass tr

Primary porcine hepatocytes with portal vein serum cultured on microcarriers or in spheroidal aggregates

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World Journal of Gastroenterology 2000年第3期6卷 365-370页

作者： Gao y Hu HZ Chen k yang JZ First Mil Med Univ Zhujiang Hosp Dept Hepatobiliary Surg Guangzhou 510282 Guangdong Provi Peoples R China

AIM To develop a culture mode providingdurable biomaterials with high yields andactivities used in bioartificial *** Hepatocytes were isolated from awhole pig liver by Seglen’s method of orthotopicperfusion with *** culture onmicrocarriers,primary porcine hepatocyteswere inoculated at a concentration of 5×10~7/mLinto the static culture systems containing 2 g/LCytodex-3,then supplemented with 100 mL/Lfetal calf serum(FCS)or 100 mL/L porcineportal vein serum(PPVS)*** aggregate culture hepatocytes wereinoculated into 100 mL siliconized flasks at aconcentration of 5.0×10~6/*** In culture on microcarriershepatocytes tended to aggregate on Cytodex-3obviously after being *** multi-cellular aggregated spheroids could be found inthe two systems 24 h-48 h after hepatocyteswere *** morphological charact-eristics and synthetic functions were maintainedfor 5 wk in FCS culture system and 8 wk in PPVSculture *** spheroidal aggregate cultureabout 80%-90% isolated hepatocytes becameaggregated spheroids 24h after cultured insuspension and mean diameter of the spheroidswas 100μ*** relationship among thehepatocytes resembled that in the liver in *** functions of albumin and urea of the spheroids were twice those of hepatocytescultured on *** As high-yields and high-activitymodes of culture on microcarriers or inspheroidal aggregate culture with portal veinserum are promising to provide biomaterials forbioartificial liver(BAL)efficiently.

关键词： porcine hepatocytes microcarriers cell culture spheroidal aggregate culture portal vein serum