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Visual reaction effects induced and stimulated by different lights on phototactic bio-behaviors in Locusta migratoria manilensis

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International Journal of Agricultural and Biological Engineering 2017年第4期10卷 173-181页

作者： Liu Qihang xin zhe Zhou Qiang School of Mechanical and Electrical Engineering Henan Institute of Science and TechnologyXinxiang 453003China College of Engineering China Agricultural UniversityBeijing 100083China

Control of locusts traditionally relies on chemical ***,chemical control had led to serious environment problems,while light trap techniques based on manipulating insect phototactic responses,are proposed to use for plague locusts *** key to high efficiency of the trap is to decide the photoelectric reaction intensities on the positive phototaxis of *** study compared the visual reaction effects of locusts with their phototactic photosensitivity through the use of spectrometry and behavior investigations,to obtain the influences of the visual spectrum characteristics on locusts positive *** results showed that the visual absorption of photons of mixed spectral light and the visual glimmer reaction of the locusts with migratory spectrum characteristics of the peak wavelength of LED lights,reflected the degree of the visual photosensitivity to light photons absorbed by the *** visual photosensitive response intensity and the phototactic aggregation effect stimulated by violet light were the most effective,showing that violet light of locusts visual trending sensitivity was consistent with the short sensitive spectrum light of insects visual electrophysiology,whereas the timeliness of the visual photosensitivity reaction and the induction effect was superior under orange light,showing that the biological behavior of locusts visual physiology reaction caused by orange light regulating locusts light rhythm was ***,weak light resulted in stronger visuospatial orientation in terms of the phototaxis of locusts and stronger light resulted in the better visual orientation towards the light *** results indicated that optical wave properties could affect the visual absorption of spectral light photons,which resulted in different visual responses to different optical frequency energies and restricted the visual bio-photosensitive induction activity of *** study provides new understanding of positive

关键词： locusta migratoria visual reaction effect phototactic bio-behavior light property bio-control

Design and optimization of a new terrain-adaptive hitch mechanism for hilly tractors

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 134-144页

作者： zhe xin Qiubo Jiang Zhongxiang Zhu Mingxi Shao College of Engineering China Agricultural UniversityBeijing 100083China

In view of the problems of poor working quality and low efficiency caused by traditional hitch mechanisms,which cannot make farm implements adapt to hillside fields for terrain-adaptive working after leveling the body of hilly tractors,a new type of terrain-adaptive hitch mechanism was designed which can adjust the transverse posture of farm implements to meet the ploughing requirements of complicated terrain in hilly and mountainous *** mechanism was mainly composed of the original hitch device and the newly added rotating *** kinematic model of each sub-mechanism was established,as well as the mathematical relation of significant performance indexes of the whole mechanism,such as lifting capacity,transverse inclination angle and tillage *** algorithm was used to optimize the lifting performance of this hitch mechanism in Matlab,so that the minimum vertical lifting force at the center of gravity of farm implements increased by 14.1%,which met the requirements of national *** ADAMS simulation calculation,it was found that different working slopes had a certain influence on the external load of each component,and terrain-adaptive hitch mechanism had little effect on the vibration characteristics of hilly *** fatigue analysis and optimization design of the key component,rotating shaft,were carried out in ANSYS Workbench,and the mass of this part reduced by 64%.A real vehicle test platform was set up to test and verify the power lifting range and working slope range of terrain-adaptive hitch *** test results showed that the actual power lifting ranged in 185-857 mm,and the maximum error from the theoretical range was only 3.1%,while the actual working slope range was from–25.9°to+23.2°,and the maximum error from the theoretical range was only 4.5%.Therefore,the terrain-adaptive hitch mechanism can meet the requirements of power lifting performance,and simultaneously can adjust the transverse posture of farm implem

关键词： hilly tractors hitch mechanism terrain-adaptive working transverse posture optimal design

An enhanced method for estimating snow water equivalent in the central part of the Tibetan Plateau using raster segmentation and eigenvector spatial filtering regression model

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Journal of Mountain Science 2022年第9期19卷 2570-2586页

作者： CHENG Qi-shan CHEN Yu-min YANG Jia-xin CHEN Yue-jun XIONG zhe-xin ZHOU An-nan School of Resource and Environment Science Wuhan UniversityWuhan 430079China Guangzhou Urban Planning&Design Survey Research Institute Guangzhou 510060China

Snow water equivalent(SWE)is an important factor reflecting the variability of *** is important to estimate SWE based on remote sensing data while taking spatial autocorrelation into *** on the segmentation method,the relationship between SWE and environmental factors in the central part of the Tibetan Plateau was explored using the eigenvector spatial filtering(ESF)regression model,and the influence of different factors on the SWE was *** sizes of 16×16,24×24 and 32×32 were selected to segment raster datasets into *** eigenvectors of the spatial adjacency matrix of the segmented size were selected to be added into the model as spatial factors,and the ESF regression model was constructed for each block in *** show that precipitation has a great influence on SWE,while surface temperature and NDVI have little *** temperature,elevation and surface temperature have completely different effects in different *** with the ordinary least square(OLS)linear regression model,geographically weighted regression(GWR)model,spatial lag model(SLM)and spatial error model(SEM),ESF model can eliminate spatial autocorrelation with the highest *** the segmentation size increases,the complexity of ESF model increases,but the accuracy is improved.

关键词： Snow water equivalent Tibetan Plateau Raster segmentation Parallel eigenvector spatial filtering

Numerical simulation on vacuum solution heat treatment and gas quenching process of a low rhenium-containing Ni-based single crystal turbine blade

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China Foundry 2016年第6期13卷 402-413页

作者： zhe-xin Xu Xiang-lin Su Qing-yan Xu Bai-cheng Liu Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) School of Materials Science and EngineeringTsinghua University

Numerical heat-transfer and turbulent flow model for an industrial high-pressure gas quenching vacuum furnace was established to simulate the heating,holding and gas fan quenching of a low rhenium-bearing Ni-based single crystal turbine *** mesh of simplified furnace model was built using finite volume method and the boundary conditions were set up according to the practical *** results show that the turbine blade geometry and the mutual shielding among blades have significant influence on the uniformity of the temperature *** temperature distribution at sharp corner,thin wall and corner part is higher than that at thick wall part of blade during heating,and the isotherms show a toroidal line to the center of thick *** temperature of sheltered units is lower than that of the remaining part of *** there is no shelteration among multiple blades,the temperature distribution for all blades is almost *** fluid velocity field,temperature field and cooling curves of the single and multiple turbine blades during gas fan quenching were also *** results indicate that the loading tray,free outlet and the location of turbine blades have important influences on the flow *** high-speed gas flows out from the nozzle is divided by loading tray,and the free outlet enhanced the two vortex flow at the end of the furnace *** closer the blade is to the exhaust outlet and the nozzle,the greater the flow velocity is and the more adequate the flow *** blade geometry has an effect on the cooling for single blade and multiple blades during gas fan quenching,and the effects in double layers differs from that in single *** single blade,the cooing rate at thin-walled part is lower than that at thick-walled part,the cooling rate at sharp corner is greater than that at tenon and blade platform,and the temperature at regions close to the internal position is decreased more slowly than that close to the surfa

关键词： Ni-based superalloy incipient melting cooling rates turbine blade

AG490: An inhibitor of hepcidin expression in vivo

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World Journal of Gastroenterology 2011年第45期17卷 5032-5034页

作者： Shu-Ping Zhang zhe Wang Li-xin Wang Si-Jin Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A liver-produced hormone, hepcidin, appears to be the key player in iron metabolism. The overexpression of hepcidin is the underlying cause of anemia of inflammation. The identification of compounds inhibiting hepcidin expression could ameliorate anemia associated with inflammation. In the current study, we have demonstrated for the first time that AG490 signifi cantly abolishes hepcidin expression in mice. Our work represents a novel approach to suppress hepcidin expression for treatment of anemia of inflammation and anemias occurring under other conditions.

关键词： AG490 Hepcidin Anemia Inflammation

A silicon-graphene-silicon transistor with an improved current gain

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Journal of Materials Science & Technology 2022年第9期104卷 127-130页

作者： Chi Liu Xu-Qi Yang Wei Ma xin-zhe Wang Hai-Yan Jiang Wen-Cai Ren Dong-Ming Sun Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Material Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China

In history,semiconductor-metal-semiconductor transistor(SMST)was proposed for frequency ***,a general fabrication method is still missing due to the unsolved technological problem of deposition of a general crystalline semiconductor on metal,and a thinner metal base is also difficult to be fabricated with high ***,due to the atomic thickness of graphene,the concept of semiconductor-graphene-semiconductor transistor(SGST)has emerged which leads to the renaissance of SMST,however the experimental study is in its *** this letter,SMST and SGST are fabricated using Si membrane *** is found the common base current gain can be improved from about 0.5%in a Si-Au-Si transistor to about 1%in a Si-Gr-Ge one,and to above 10%in a Si-Gr-Si one,which is attributed to both the ultra-thin thickness and the quantum capacitance effect of graphene.

关键词： Semiconductor metal semiconductor transistor Graphene base transistor Graphene base heterojunction transistor

The relationship between SPARC expression in primary tumor and metastatic lymph node of resected pancreatic cancer patients and patients' survival

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Hepatobiliary & Pancreatic Diseases International 2017年第1期16卷 104-109页

作者： xin-zhe Yu Zhong-Yi Guo Yang Di Feng Yang Qi Ouyang De-Liang Fu Chen Jin Department of Pancreatic Surgery Huashan HospitalFudan UniversityShanghai 200040China Department of Pathology Huashan HospitalFudan UniversityShanghai 200040China Institute of Pancreatic Disease Fudan UniversityShanghai 200040China

BACKGROUND： Previous researches in pancreatic cancer demonstrated a negative correlation between secreted protein acidic and rich in cysteine （SPARC） expression in primary tumor and survival, but not for SPARC expression in lymph node. In the present study, we aimed to evaluate the SPARC expression in various types of tissues and its impact on patients＇ prognosis. METHODS： The expression of SPARC was examined by immunohistochemistry in resected pancreatic cancer specimens. Kaplan-Meier analyses and Cox proportional hazards regres- sion were applied to assess the mortality risk. RESULTS： A total of 222 tissue samples from 73 patients were collected to evaluate the SPARC expression, which included 73 paired primary tumor and adjacent normal tissues, 38 paired metastatic and normal lymph nodes. The proportion of posi tive SPARC expression in metastatic lymph node was high （32/38）, whereas in normal lymph node it was negative （0/38）. Positive SPARC expression in primary tumor cells was associ- ated with a significantly decreased overall survival （P=0.007） and disease-free survival （P=0.003）, whereas in other types of tissues it did not show a predictive role for prognosis. Univariate and multivariate analyses both confirmed this significance. CONCLUSION： SPARC can serve a dual function role as both predictor for prognosis and potentially biomarker for lymph node metastasis in resected pancreatic cancer patients.

关键词： pancreatic cancer SPARC expression immunohistochemistry prognostic marker lymph node metastasis

Cross-layer all-interface defect passivation with pre-buried additive toward efficient all-inorganic perovskite solar cells

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Carbon Energy 2024年第9期6卷 283-291页

作者： Qiurui Wang Jingwei Zhu Yuanyuan Zhao Yijie Chang Nini Hao zhe xin Qiang Zhang Cong Chen Hao Huang Qunwei Tang College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdaoChina College of Materials Science and Engineering Sichuan UniversityChengduChina Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials School of ResourcesEnvironment and MaterialsGuangxi UniversityNanningChina Institute of Carbon Neutrality College of Chemical and Biological EngineeringShandong University of Science and TechnologyQingdaoChina

The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and ***,a comprehensive manipulation of the buried interface in terms of the transport layer,buried interlayer,and perovskite layer has been largely ***,we propose the use of a volatile heterocyclic compound called 2-thiopheneacetic acid(TPA)as a pre-buried additive in the buried interface to achieve cross-layer all-interface defect passivation through an in situ bottom-up infiltration diffusion *** not only suppresses the serious interfacial nonradiative recombination losses by precisely healing the interfacial and underlying defects but also effectively enhances the quality of perovskite film and releases the residual strain of perovskite *** to this versatility,TPA-tailored CsPbBr3 PSCs deliver a record efficiency of 11.23% with enhanced long-term *** breakthrough in manipulating the buried interface using TPA opens new avenues for further improving the performance and reliability of PSC.

关键词： buried interfaces charge recombination defect passivation inorganic perovskite solar cells strain relaxation

Prevalence and Related Factors of Falls among the Elderly in an Urban Community of Beijing

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Biomedical and Environmental Sciences 2009年第3期22卷 179-187页

作者： PU-LIN YU ZHAO-HUI QIN JING SHI JUAN ZHANG MEI-zhe xin zheNG-LAI WU zheN-QIU SUN School of Public Health Central South University Changsha 410078 Hunan China Department of Public Health Xuzhou Medical College Xuzhou 221002 Jiangsu China Institute of Geriatrics Beijing Hospital Ministry of Health Beijing 100730 China Department of Applied Health Science Indiana University 47408 Bloomington Indiana USA Office of Program Management Chinese Preventive Medicine Association Beijing 100009 China Department of Epidemiology Peking Union Medical College Beijing 100005 China

Objective To understand the prevalence, consequences and risk factors of falls among urban community-dwelling elderly in Beijing. Methods A cross-sectional study was conducted in Longtan Community, Beijing. A total of 1512 individuals aged 60 years or over were selected by stratified cluster sampling. Data regarding the frequency of falls in the previous year, as well as circumstances, consequence and related factors of falls were collected from the elderly through face-to-face interviews with questionnaires in their home. Results The prevalence of falls was 18.0% on the average among 1512 participants, higher in women （20.1%） than in men （14.9%）（P=0.006）, and increased with age （Х^2 for trend=10.37, P=0.001）. The total rate of falls-induced injuries among the fallers was 37.7%. Falls usually resulted in soft-tissues bruises （58.7%）, fear of repeated episodes of falls （58.8%）, loss of independence and confidence in movement （35.7%） and even in hip fracture. In addition to the burden of medical care, falls also generated a big economic burden. Occurrence of falls was significantly associated with both intrinsic and extrinsic factors. The related factors of falls in the elderly included age≥60-70 years, femininity, less physical activities, fear of future falls, living alone, severely impaired vision, health problem-impacted activities of daily living, chronic diseases （diabetes, hypertension, postural hypotension, stroke sequela, cataract, arthritis, dementia and depression）, medications （psychoactive, anti-diabetic）, gait imbalance, high bed and faintly-lighted stairway. Conclusion The prevalence of falls among urban community-dwelling elderly in Beijing is closely associated with significant associated with intrinsic and extrinsic factors. Efforts to prevent falls in the elderly should be made at community level.

关键词： Falls Prevalence Old people Prevention