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Inverse analysis of coupled carbon-nitrogen cycles against multiple datasets at ambient and elevated CO_(2)

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Journal of Plant Ecology 2016年第3期9卷 285-295页

作者： Zheng Shi Yuanhe Yang xuhui zhou Ensheng Weng Adrien C.Finzi Yiqi Luo Department of Botany and Microbiology University of OklahomaNormanOK 73019USA State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Department of Biology Boston UniversityBostonMA 02215USA

Aims Carbon(C)sequestration in terrestrial ecosystems is strongly regulated by nitrogen(N)***,key parameters that determine the degree of N regulation on terrestrial C sequestration have not been well *** Here,we used a Bayesian probabilistic inversion approach to estimate 14 target parameters related to ecosystem C and N interactions from 19 datasets obtained from Duke Forests under ambient and elevated carbon dioxide(CO_(2)).Important FindingsOur results indicated that 8 of the 14 target parameters,such as C:N ratios in most ecosystem compartments,plant N uptake and external N input,were well constrained by available datasets whereas the others,such as N allocation coefficients,N loss and the initial value of mineral N pool were poorly *** analysis showed that elevated CO_(2)led to the increases in C:N ratios in foliage,fine roots and ***,elevated CO_(2)stimulated plant N uptake and increased ecosystem N capital in Duke Forests by 25.2 and 8.5%,*** addition,elevated CO_(2)resulted in the decrease of C exit rates(*** in C residence times)in foliage,woody biomass,structural litter and passive soil organic matter,but the increase of C exit rate in fine *** results demonstrated that CO_(2)enrichment substantially altered key parameters in determining terrestrial C and N interactions,which have profound implications for model improvement and predictions of future C sequestration in terrestrial ecosystems in response to global change.

关键词： Bayesian probabilistic inversion carbon-nitrogen interactions carbon-nitrogen coupled model Duke FACE.

Multi-field Coupled Inverse Hall–Petch Relations for Ferroelectric Nanocrystals

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Acta Mechanica Solida Sinica 2024年第1期37卷 139-147页

作者： Xiaodong Zhang Wei Yan xuhui Lou Yujun Chen Zhihong zhou Qingyuan Wang Lianhua Ma Xiaobao Tian Non-Destructive Testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaoding 071002China AVIC Huiyang Aviation Propeller Co. LtdBaoding 071051China Department of Mechanics and Engineering Sichuan UniversityChengdu 610065China Yibin Institute of Industrial Technology Sichuan University Yibin ParkYibin 644000China Research Institute of Interdisciplinary Sciences(RISE) Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Tailoring grain size can improve the strength of polycrystals by regulating the proportion of grains to grain boundaries and the interaction *** the grain size decreases to the nanoscale,the deformation mechanism in polycrystals shifts from being primarily mediated by dislocations to deformation occurring within the grains and grain ***,the mechanism responsible for fine-grain strengthening in ferroelectric materials remains unclear,primarily due to the complex multi-field coupling effect arising from spontaneous *** molecular dynamics simulations,we investigate the strengthening mechanism of barium titanate(BaTiO3),with extremely fine-grain *** material exhibits an inverse Hall–Petch relationship between grain size and strength,rooting in the inhomogeneous concentration of atomic strain and grain ***,we present a theoretical model to predict the transition from the inverse Hall–Petch stage to the Hall–Petch stage based on strength variations with size,which aligns well with the simulation *** has been found that the piezoelectric properties of the BaTiO3 are affected by polarization domain switching at various grain *** study enhances our understanding of the atomic-scale mechanisms that contribute to the performance evolution of fine-grain nano-ferroelectric *** also provides valuable insights into the design of extremely small-scale ferroelectric components.

关键词： Ferroelectrics Multi-field coupling Molecular dynamics Fine-grain reinforcement Inverse Hall-Petch effect

Vibration-assisted material damage mechanism:From indentation cracks to scratch cracks

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Chinese Journal of Aeronautics 2024年第8期37卷 527-546页

作者： Bingrui LV Bin LIN Tianyi SUI Chunyan LIU Jinshuo ZHANG Longfei WANG xuhui CHEN Jingguo zhou Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin UniversityTianjin 300072China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing 100076China

Vibration-assisted grinding is one of the most promising technologies for manufacturing optical components due to its efficiency and quality ***,the damage and crack propagation mechanisms of materials in vibration-assisted grinding are not well *** order to elucidate the mechanism of abrasive scratching during vibration-assisted grinding,a kinematic model of vibration scratching was *** influence of process parameters on the evolution of vibration scratches to indentation or straight scratches is revealed by displacement metrics and velocity ***,scratch and vibration scratch experiments were performed on quartz glass,and the results showed that the vibration scratch cracks are a combination of indentation cracks and scratch *** scratch cracks change from indentation cracks to scratch cracks as the indenter moves from the entrance to the exit of the workpiece or as the vibration frequency changes from high to low.A vertical vibration scratch stress field model is established for the first time,which reveals that the maximum principal stress and tensile stress distribution is the fundamental cause for inducing the transformation of the vibration scratch cracking *** model provides a theoretical basis for understanding of the mechanism of material damage and crack propagation during vibration-assisted grinding.

关键词： Vibration assisted grinding Indentation Vibration scratch Material removal mechanism Stress field model Crack propagation mechanism

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经皮穴位电刺激在酒精依赖患者中的应用效果

实用临床医药杂志 2024年第2期28卷 38-42页

作者：谢婷侯超周旭辉郭育君练宇泽曾亚琦湖南省脑科医院/湖南省第二人民医院精神科湖南长沙410007

目的观察经皮穴位电刺激在酒精依赖患者心理渴求和稽延性戒断症状中的应用效果。方法选取在湖南省脑科医院酒瘾科住院的120例酒精依赖完成急性脱瘾期的男性患者为研究对象,根据患者治疗方式的不同分为常规药物组、经皮穴位电刺激组及假... 详细信息

目的观察经皮穴位电刺激在酒精依赖患者心理渴求和稽延性戒断症状中的应用效果。方法选取在湖南省脑科医院酒瘾科住院的120例酒精依赖完成急性脱瘾期的男性患者为研究对象,根据患者治疗方式的不同分为常规药物组、经皮穴位电刺激组及假刺激组,每组40例。常规药物组采用苯二氮[艹卓]类药物替代递减以及支持性对症治疗,经皮穴位电刺激组采用常规治疗联合经皮穴位电刺激,假刺激组采用常规治疗联合模拟经皮穴位电刺激。比较3组患者治疗前后焦虑自评量表(SAS)评分及抑郁自评量表(SDS)评分、饮酒迫切性量表(AUQ)评分、视觉模拟评分法(VAS)评分、匹兹堡睡眠质量指数(PSQI)评分及复发情况。结果治疗后,3组患者SAS、SDS、AUQ及VAS评分均较治疗前降低,且经皮穴位电刺激组以上评分均低于常规药物组及假刺激组,差异有统计学意义(P<0.05)。治疗后,3组患者睡眠质量、入睡时间、睡眠时间、睡眠效率、睡眠障碍、催眠药物、日间功能障碍评分及PSQI总分均低于治疗前,且经皮穴位电刺激组以上评分均低于常规药物组及假刺激组,差异有统计学意义(P<0.05)。经皮穴位电刺激组复发率低于常规药物组及假刺激组,差异有统计学意义(P<0.05)。结论相较于常规治疗及模拟经皮电刺激,经皮穴位电刺激治疗更有利于减轻患者焦虑、抑郁及失眠等稽延性戒断症状严重程度,并利于降低患者心理渴求程度,从而降低复发率。

关键词：经皮穴位电刺激酒精依赖心理渴求稽延性戒断症复发

A 16-bit 18-MSPS flash-assisted SAR ADC with hybrid synchronous and asynchronous control logic

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Journal of Semiconductors 2024年第6期45卷 3-12页

作者： Junyao Ji Xinao Ji Ziyu zhou Zhichao Dai xuhui Chen Jie Zhang Zheng Jiang Hong Zhang School of Microelectronics Xi'an Jiaotong UniversityXi'an 710049China Qingdao Hi-image Tech.Co.Ltd. Qingdao 266100China

This paper presents a 16-bit,18-MSPS(million samples per second)flash-assisted successive-approximation-register(SAR)analog-to-digital converter(ADC)utilizing hybrid synchronous and asynchronous(HYSAS)timing control logic based on an on-chip delay-locked loop(DLL).The HYSAS scheme can provide a longer settling time for the capacitive digital-to-analog converter(CDAC)than the synchronous and asynchronous SAR ***,the issue of incomplete settling or ringing in the DAC voltage for cases of either on-chip or off-chip reference voltage can be solved to a large *** addition,the fore-ground calibration of the CDAC’s mismatch is performed with a finite-impulse-response bandpass filter(FIR-BPF)based least-mean-square(LMS)algorithm in an off-chip FPGA(field programmable gate array).Fabricated in 40-nm CMOS process,the proto-type ADC achieves 94.02-dB spurious-free dynamic range(SFDR),and 75.98-dB signal-to-noise-and-distortion ratio(SNDR)for a 2.88-MHz input under 18-MSPS sampling rate.

关键词： SAR ADC control logic reference ringing DAC incomplete settling

Large eddy simulation study of 3D wind field in a complex mountainous area under different boundary conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 541-556页

作者： Yan LI Lei YAN xuhui HE School of Civil Engineering Central South UniversityChangsha410075China National Engineering Research Center for High-speed Railway Construction Changsha410075China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structures Changsha410075China

Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous *** simulation boundary conditions,such as the height and length of the computational domain or the characteristics of inflow turbulence,can significantly impact the quality of *** this study,we examined these boundary conditions within the context of the mountainous terrain around a long-span cable-stayed bridge using a wind tunnel *** sizes of computational domains and turbulent incoming wind velocities were used in large eddy *** results show that when the height of the computational domain is five times greater than the height of the terrain model,there is minimal influence from the top wall on the wind field characteristics in this complex mountainous *** the length of the wake region of the computational domain has negligible effects on the wind *** in the inlet boundary reduces the length of the wake region on a leeward hill with a low slope,but has less impact on the mean wind velocity of steep hills.

关键词： Large eddy simulation(LES) Spectral representation method Recycling method High mountainous canyon Wind characteristics Atmospheric boundary layer Computational domain

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带焊缝圆灯柱气动特性及焊缝影响机理研究

地震工程与工程振动 2023年第6期43卷 227-235页

作者：周旭辉中铁十一局集团有限公司湖北武汉430061 长沙理工大学土木学院湖南长沙430007

为了研究某实桥带焊缝圆灯柱的气动特性以及焊缝对灯柱涡激振动的影响机理,开展了灯柱刚性节段测压模型风洞试验,测试了无焊缝工况以及0°~180°焊缝位置的灯柱周向压力分布,分析了灯柱气动力以及流体卡门涡脱强度,揭示了焊缝对灯柱涡... 详细信息

为了研究某实桥带焊缝圆灯柱的气动特性以及焊缝对灯柱涡激振动的影响机理,开展了灯柱刚性节段测压模型风洞试验,测试了无焊缝工况以及0°~180°焊缝位置的灯柱周向压力分布,分析了灯柱气动力以及流体卡门涡脱强度,揭示了焊缝对灯柱涡激振动的影响机理。研究结果表明:焊缝对灯柱的气动特性影响显著,不同的焊缝位置可以激发不同的流动模式,当焊缝在灯柱前驻点或者原分离点后侧时,灯柱气动特性受焊缝影响较小。当焊缝在B区域(21°~33°)和C区域(36°~63°)时,流体在焊缝附近发生分离-再附-再分离现象,卡门涡脱强度降低,灯柱的涡激振动被抑制。当焊缝在D区域(63°~78°)时,流体在焊缝位置直接涡脱,伴随着脉动风压和卡门涡脱强度的增强,使灯柱的涡激振动增大;焊缝尺寸的变化不会改变灯柱的气动力系数随焊缝位置的变化规律,但是可能会影响涡激振动风速锁定区间和振动幅值。

关键词：带焊缝圆灯柱风洞试验测压模型气动特性焊缝影响机理

Urinary Bladder Cancer: The Current and Potential Role of MR Imaging in Non-Distant Metastatic Lesions

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Journal of Cancer Therapy 2013年第2期4卷 504-512页

作者： Huanjun Wang Yan Guo xuhui zhou Dong Yang Department of Radiology The First Affiliated Hospital Sun Yat-sen University Guangzhou China

Urinary bladder cancer is the second most common genitourinary malignancy in Westernized countries. A number of emerging imaging techniques have recently been reported in the literature for use in imaging bladder cancer. While the explicit application of MR imaging in bladder cancer especially in non-distant bladder cancer or bladder cancer localized in pelvic remains uncertain and awaits a thorough evaluation. Therefore, this article aims to make a systematic review of previous literature and provide a complete assessment of the value of MR as an evolving imaging tool in localized urinary bladder cancer application. Studies were conducted by searching the MEDLINE and PubMed databases up to 2012 using both medical subject heading (Mesh) and a free text method like “urinary bladder cancer”, “magnetic resonance imaging” or “MRI”, “diffusion weighted imaging” or “DWI”. About 53 articles were selected and analyzed which were considered to be associated with the objective of this systematic review (Table 1). Results showed that MRI especially the newer functional imaging technique like DWI may has a great potential role in localized bladder cancer like early detection, staging, evaluation of tumor aggressiveness and therapeutic responsiveness of patients in the assessment of urinary bladder cancer and so forth. Newer MRI has already proceeded promising results in bladder cancer application;and the explicit role of newer MRI in bladder cancer patients still needs further research and awaits to be thoroughly evaluated.

关键词： Urinary Bladder Cancer Staging Progression Magnetic Resonance Imaging (MRI) Diffusion Weighted Imaging (DWI)

Engineered extracellular vesicles for delivery of siRNA promoting targeted repair of traumatic spinal cord injury

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Bioactive Materials 2023年第5期23卷 328-342页

作者： Yuluo Rong Zhuanghui Wang Pengyu Tang Jiaxing Wang Chengyue Ji Jie Chang Yufeng Zhu Wu Ye Jianling Bai Wei Liu Guoyong Yin Lipeng Yu xuhui zhou Weihua Cai Department of Orthopedics The First Affiliated Hospital of Nanjing Medical UniversityNanjing210029JiangsuChina Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjing210029JiangsuChina Department of Orthopedics Second Affiliated Hospital of Naval Medical UniversityShanghai200003China Department of Orthopedics Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong UniversityShanghai200003China

Spinal cord injury(SCI)is a severe disease of the nervous system that causes irreparable damage and loss of function,for which no effective treatments are available to *** extracellular vesicles(EVs)carrying therapeutic molecules hold promise as an alternative SCI therapy depending on the specific functionalized EVs and the appropriate engineering *** this study,we demonstrated the design of a drug delivery system of peptide CAQK-modified,siRNA-loaded EVs(C-EVs-siRNA)for SCI-targeted *** peptide CAQK was anchored through a chemical modification to the membranes of EVs isolated from induced neural stem cells(iNSCs).CCL2-siRNA was then loaded into the EVs through *** modified EVs still maintained the basic properties of EVs and showed favorable targeting and therapeutic effects in vitro and in vivo.C-EVs-siRNA specifically delivered siRNA to the SCI region and was taken up by target cells.C-EVs-siRNA used the inherent anti-inflammatory and neuroreparative functions of iNSCs-derived EVs in synergy with the loaded siRNA,thus enhancing the therapeutic effect against *** combination of targeted modified EVs and siRNA effectively regulated the microenvironmental disturbance after SCI,promoted the transformation of microglia/macrophages from M1 to M2 and limited the negative effects of the inflammatory response and neuronal injury on functional recovery in mice after ***,engineered EVs are a potentially feasible and efficacious treatment for SCI,and may also be used to develop targeted treatments for other diseases.

关键词： Extracellular vesicles Spinal cord injury siRNA Microglia/macrophages polarization Induced neural stem cells