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Journal of materials Science & Technology 2013年第12期29卷 1116-1122页

作者： Z.A.luo G.m.Xie Z.Y.ma G.l.Wang G.D.Wang State key laboratory of Rolling and Automation Northeastern University Shenyang National laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences

As-extruded Zk60 and Zk60-Y magnesium alloy plates were successfully processed via friction stir processing （FSP） at a tool rotation rate of 1600 r/rain and a traverse speed of 200 mm/min. FSP resulted in the formation of equiaxed recrystallized microstructures with the average grain sizes of ,-8.5 and -4.7 μm in the Zk60 and Zk60-Y alloys, respectively. moreover, FSP broke and dispersed the mgZn2 and W-phase （mg3Zn3Y2） particles and dissolved mgZn2 phase in the FSP Zk60 alloy. With the addition of rare earth element yttrium （Y） into the Zk60 alloy, the ratio of the high angle grain boundaries （HAGBs） in the FSP alloys increased from 64% to 90%, and a certain amount of twins appeared in the FSP Zk60-Y alloy. The maximum elongation of 1200% and optimum strain rate of 3 X 10-3 s-1 achieved at 450 °C in the FSP Zk60-Y alloy were substantially higher than those of the FSP Zk60 alloy. This is attributed to the fine grains with high ratio of HAGBs and the distribution of a large number of dispersed second phase particles with high thermal stability in the FSP Zk60-Y alloy. Grain boundary sliding was identified as the primary deformation mechanism in the FSP Zk60 and Zk60-Y alloys from the superplastic data analyses and surficial morphology observations.

关键词： magnesium alloy Friction stir processing Rare earth element microstructure Superplasticity

Effect of firing conditions ＆ release height on terminal performance of submunitions and conditions for optimum height of release

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Defence Technology（防务技术） 2017年第3期13卷 200-205页

作者： l.k.Gite A.Anandaraj R.S.Deodhar D.k.Joshi k.m.Rajan Armament Research Development Establishment (ARDE) Defence Research Development Organization Ministry of Defence Government of India

Submunitions should exhibit optimum terminal performance at target end when released from certain pre-determined height. Selection of an optimum height of release of the submunitions depends on the terminal parameters like forward throw, remaining velocity, impact angle and flight time. In this paper,the effects of initial firing conditions and height of release on terminal performance of submunitions discussed in detail. For different height of release, the relation between range and forward throw is also established & validated for a number of firing altitude and rocket configurations.

关键词：最佳高度终端子弹性能射击剩余速度飞行时间冲击角

mElD score,insulin-like growth factor 1 and cytokines on bone density in end-stage liver disease

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World Journal of Hepatology 2011年第6期3卷 157-163页

作者： Rebecca mitchell Jill mcDermid mang m ma Constance l Chik Divisions of Endocrinology and metabolism Department of MedicineFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAB T6G 2S2AlbertaCanada Division of Gastroenterology Department of MedicineFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAB T6G 2S2AlbertaCanada

AIm:To determine the contributions of insulin-like growth factor 1 (IGF-1),cytokines and liver disease severity to bone mineral density in patients ***:Serum IGF-1,tumor necrosis factor-α (TNFα) and interleukin 6 (Il-6) were measured and the model for End-Stage liver Disease (mElD) score calculated in 121 adult patients referred to a single centre for liver *** mineral density (BmD) of the lumbar spine and femoral neck were assessed via dual energy X-ray ***,liver disease etiology,medication use and relevant biochemistry were ***:A total of 117 subjects were included,with low BmD seen in 68.6%,irrespective of disease *** multivariable analysis,low body mass index (BmI),increased bone turnover and low IGF-1 were independent predictors of low spinal bone *** the hip,BmI,IGF-1 and vitamin D status were *** prevalent elevations of TNFα and Il-6,levels did not correlate with degree of bone *** mElD score failed to predict low BmD in this pre-transplant ***:Osteopenia/osteoporosis is common in advanced liver *** serum IGF-1 is weakly predictive but serum cytokine and mElD score fail to predict the severity of bone disease.

关键词： Hepatic osteodystrophy Insulin-like growth factor-1 Cytokines Bone mineral density mElD score

Therapeutic Potential of Glucagon-like Peptide-1 Cleavage Product for Alzheimer’s Disease

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Neuroscience Bulletin 2019年第5期35卷 934-936页

作者： Stephen m. Day Tao ma Department of Internal medicine Gerontology and Geriatric Medicine Wake Forest School of Medicine Winston-Salem NC 27157 USA Department of Physiology and Pharmacology Wake Forest School of Medicine Winston-Salem NC 27157 USA Department of Neurobiology and Anatomy Wake Forest School of Medicine Winston-Salem NC 27157 USA

Alzheimer’s disease (AD) is a devastating neurodegenerative disease and the most common form of dementia in the elderly. Concurrent with an aging population, the incidence of AD has been rising steadily and become a global threat to public health [1]. Unfortunately, there are currently no effective interventions that can cure AD or slow its progression, and recently finished clinical trials targeting brain amyloid-b (Ab) accumulation have not succeeded in improving cognitive impairments in AD patients [1]. Thus, it is necessary and urgent to identify alternative diseasemodifying strategies to alleviate AD pathophysiology. In this perspective article, we focus on glucagon-like peptide- 1 (GlP-1), specifically its natural cleavage product GlP-1 (9-36), as a potential therapeutic approach for AD.

关键词： Alzheimer GlP-1 its AD has can is

A Conceptual Design Study for the Error Field Correction Coil Power Supply in JT-60SA

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Plasma Science and Technology 2013年第3期15卷 257-260页

作者： m.maTSUkAWA k.SHImaDA k.YAmaUCHI E.GAIO A.FERRO l.NOVEllO Japan Atomic Energy Agency 801-1 MukoyamaNakaIbaraki 311-0193Japan Consorzio RFX-EURATOm ENEA Association C.so Stati Uniti 435127 PadovaItaly Fusion for Energy Boltzmannstr 2 Garching 85748Germany

This paper describes a conceptual design study for the circuit configuration of the Error Field Correction Coil （EFCC） power supply （PS） to maximize the expected performance with reasonable cost in JT-60SA. The EFCC consists of eighteen sector coils installed inside the vacuum vessel, six in the toroidal direction and three in the poloidal direction, each one rated for 30 kA-turn. As a result, star point connection is proposed for each group of six EFCC coils installed cyclically in the toroidal direction for decoupling with poloidal field coils. In addition~ a six phase inverter which is capable of controlling each phase current was chosen as PS topology to ensure higher flexibility of operation with reasonable cost.

关键词： JT-60SA error field correction coil power supply inverter multi-phase

mechanistic Investigation into the Role of Aluminum Diffusion in the Oxidation Behavior of Cryomilled NiCrAlY Bond Coat

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Journal of Wuhan University of Technology(materials Science) 2016年第1期31卷 35-43页

作者： kaka ma Xiaochuan TANG Julie m SCHOENUNG Department of Chemical Engineering and materials Science University of California Davis Genome and Biomedical Science Facility Genome CenterUniversity of California Davis

High temperature oxidation behavior of the bond coat layer is a critical factor that controls the failure mechanism of thermal barrier coatings（TBCs）.Previous work reveald that TBCs with cryomilled NiCrAlY bond coats exhibited an improved oxidation behavior compared to equivalent TBCs with conventional bond *** cryomilled NiCrAlY bond coats contributed to a slower growth rate of thermally grown oxides（TGO） with a final thinner thickness and enhanced homogeneity in TGO *** better understand the improved oxidation behavior,a mechanistic investigation based on diffusion theory and quantum mechanics is performed to elucidate the role of aluminum diffusion in the oxidation behavior and how the microstructural features of the cryomilled NiCrAlY bond coats,i e,the creation of a thermally stable,uniform distribution of ultrafine Al-rich oxide dispersoids,affect the diffusion kinetics of Al and the migration of free *** is revealed that these Al-rich oxide dispersoids result in a uniform diffusion of Al and slow migration of free electrons within the NiCrAlY bond coat,consequently leading to the improved oxidation behavior.

关键词： nickel alloys coatings oxidation diffusion

Assessing the spatiotemporal distributions of evapotranspiration in the Three Gorges Reservoir Region of China using remote sensing data

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Journal of mountain Science 2018年第12期15卷 2676-2692页

作者： ma Ze-zhong RAY Ram l HE Yi-ping Chongqing Institute of Surveying and Planning for land Resource and Housing Chongqing 400020China Cooperative Agricultural Research Center College of Agriculture and Human SciencesPrairie View A&M UniversityPrairie ViewTX 77446USA EDF Renewal Energy San DiegoCA 92118USA

Evapotranspiration(ET) is a critical component of the global hydrological cycle, and it has a large impact on water resource management as it affects the availability of freshwater resources. It is important to understand the hydrological cycle for the water resources planning and management. This study used moderate Resolution Imaging Spectroradiometer(mODIS) satellite derived ET, and potential evapotranspiration(PET) and Tropical Rainfall measuring mission(TRmm) satellite derived precipitation datasets to assess the spatial and temporal distributions of ET, PET, and precipitation during the study period at Three Gorges Reservoir(TGR) region. Based on the topographic variations and land-use/land-cover distributions, the study region which includes five counties of Hubei Province and nineteen counties of Chongqing municipality was divided into four study zones. The ET and precipitation data were evaluated using in situ observations. The ET, PET, and precipitation data were compared to analyze the spatial and long-term(2001-2016) temporal distributions of average annual ET, PET, and precipitation, and to understand the relationships between them in the study region. The results showed that each selected zone had highest ET at the counties with the Yangtze River passing through whereas lowest at the counties which were located away from the river. Results also showed increasing trends in ET and PET from south-west to north-east in the study region. Analysis showed TGR had a significant impact on spatial and temporal distributions of ET and PET in the study region. Therefore, this study helps to understand the impact of TGR on spatial and temporal distributions of ET and PET during and after the construction.

关键词： Evapotranspiration Precipitation Tropical Rainfall measuring mission (TRmm) moderate Resolution Imaging Spectroradiometer (mODIS) Three Gorges Reservoir Potential Evapotranspiration

Biochar-Soil Interactions in Four Agricultural Soils

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Pedosphere 2015年第5期25卷 729-736页

作者： Noraini m.JAAFAR Peta l.ClODE lynette k.ABBOTT Soil Biology and molecular Ecology Group School of Earth and Environment (M087)and UWA Institute of AgricultureThe University of Western Australia Department of land management Faculty of AgricultureUniversiti Putra Malaysia Centre for microscopy Characterisation and Analysis (M010)The University of Western Australia

Soils in south-western Australia are highly weathered and deficient in nutrients for agricultural production. Addition of biochar has been suggested as a mean of improving soil C storage, texture and nutrient retention of these soils. Clay amendment in sandy soils in this region is a management practice used to improve soil conditions, including water repellence. In this study a woody biochar(Simcoa biochar) was characterised using scanning electron microscopy before, and four weeks after, it was incorporated into each of four soils differing in clay content and organic matter. Scanning electron microscopy of Simcoa biochar after incubation in soil showed different degrees of attachment of soil particles to the biochar surfaces after 28 d. In addition, the effects of three biochars, Simcoa biochar, activated biochar and Wundowie biochar, on soil microbial biomass C and soil respiration were investigated in a short-term incubation experiment. It was hypothesised that all three biochars would have greater potential to increase soil microbial activity in the soil that had higher organic matter and clay. After 28-d incubation in soil, all three biochars had led to a higher microbial biomass C in the clayey soil, but prior to this time, less marked differences were observed in microbial biomass C among the four soils following biochar application.

关键词： clay amendment microbial biomass carbon scanning electron microscopy soil respiration

modulating neuronal plasticity with choline

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Neural Regeneration Research 2019年第10期14卷 1697-1698页

作者： Eunice W. m. Chin Eyleen l.k. Goh Neuroscience Academic Clinical Programme Duke-NUS Medical SchoolSingaporeSingapore Department of Research National Neuroscience InstituteSingaporeSingapore

The American psychologist William James once wrote that nervous tissue seems to be endowed with a “very extraordinary” degree of plasticity. To be plastic means to be capable of being molded, receiving shape, or being made to assume a desired form. This can be achieved consequential to changes in the internal and/or external environment. Being plastic, neurons are highly able to amend their structural and functional output, through alteration of their morphology, activation of intracellular signaling cascades, regulation of synaptic density and neurotransmitter release, or a combination of these events.

关键词： The American psychologist tissue seems to be endowed combination of these events

Soil microbial Responses to Biochars Varying in Particle Size,Surface and Pore Properties

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Pedosphere 2015年第5期25卷 770-780页

作者： Noraini m.JAAFAR Peta l.ClODE lynette k.ABBOTT Soil Biology and molecular Ecology Group School of Earth and Environment (M087) and UWA Institute of AgricultureThe University of Western Australia Department of land management Faculty of AgricultureUniversiti Putra Malaysia Centre for microscopy Characterisation and Analysis (M010)The University of Western Australia

Biochars are known for their heterogeneity, especially in pore and surface structure associated with pyrolysis processes and sources of feedstocks. The surface area of biochar is likely to be an important determinant of the extent of soil microbial attachment, whereas the porous structure of biochar is expected to provide protection for soil microorganisms. Potential interactions between biochars from different sources and with different particle sizes were investigated in relation to soil microbial properties in a short-term incubation study. Three particle size （sieved） fractions （0.5-1.0, 1.0-2.0 and 2.0-4.0 mm） from three woody biochars produced from jarrah wood, jarrah and wandoo wood and Australian wattle branches, respectively, were incubated in soil at 25 ℃ for 56 d. Observation by scanning electron microscopy （SEm） and characterisation of pore and surface area showed that all three woody biochars provided potential habitats for soil microorganisms due to their high porosity and surface areas. The biochars were structurally heterogeneous, varying in porosity and surface structure both within and between the biochar sources. After the 56-d incubation, hyphal colonisation was observed on biochar surfaces and in larger biochar pores. Soil clumping occurred on biochar particles, cementing and covering exposed biochar pores. This may have altered surface area and pore availability for microbial colonisation. Transient changes in soil microbial biomass, without a consistent trend, were observed among biochars during the 56-d incubation.

关键词： microbial biomass, microbial colonisation, microbial habitats, porosity scanning electron microscopy, surface structure