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时距呈现阶段的时间压力对时距知觉的影响

科学通报 2016年第30期61卷 3258-3267页

作者：李鑫郑美红清华大学心理学系北京100084

时距知觉是指对从毫秒到分钟级时间的知觉,而内部时钟模型是被广泛认同的揭示时距知觉机制的模型.内部时钟模型认为时距知觉包括时钟阶段、记忆阶段和决策阶段,其中时钟阶段是时间信息的累积阶段,是时距知觉过程的基础和核心,在实验中... 详细信息

时距知觉是指对从毫秒到分钟级时间的知觉,而内部时钟模型是被广泛认同的揭示时距知觉机制的模型.内部时钟模型认为时距知觉包括时钟阶段、记忆阶段和决策阶段,其中时钟阶段是时间信息的累积阶段,是时距知觉过程的基础和核心,在实验中对应于向被试呈现需要估计时距的阶段,即时距呈现阶段.与以往的研究不同,本研究通过设定时距呈现阶段的数学任务(实验一为中数判断,实验二为加减计算)的时间限制来引发不同程度的时间压力,考察了时距呈现阶段的时间压力对时距知觉的影响.两个实验的结果均显示,时间压力条件下的时距估计相对于无时间压力条件表现出显著的低估倾向,这表明时距呈现阶段的时间压力显著影响了时距知觉的准确性.

关键词：时间压力时距知觉时距呈现阶段准确性数学任务

Predictors of complications after prophylactic ileostomy reversal for rectal cancer:A retrospective study

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1354-1362页

作者： Quan Lv xin-Peng Shu Dong Peng Si-Qi li zheng Xiang Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Chongqing Key Laboratory of Department of General Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Previous studies have analyzed the risk factors for complications after ileostomy reversal for rectal cancer(RC),but there were significant differences in the reported risk factors for complications after stoma *** studies have analyzed the risk factors for stoma-related complications and overall postoperative com-plications *** To analyze the risk factors for overall complications and stoma-related complications after ileostomy reversal for patients with *** This was a retrospective study of 439 patients who underwent ileostomy reversal at a clinical center and were followed up between September 2012 and September *** variables are expressed as the mean±SD and were analyzed with independent-sample t tests,while frequency variables are expressed as n(%),and theχ2 test or Fisher’s exact test was *** and multivariate logistic regression analyses were used to identify predictors of overall complications and stoma-related *** The overall complication rate after ileostomy reversal was 11.4%.Patients with lower preoperative albumin concentration(Plikely to experience postoperative *** incidence of stoma-related complications was 6.4%.Analysis of the study showed that a higher body mass index(BMI)(Plikely to result in stomarelated complications *** logistic regression analysis revealed that a lower preoperative albumin level(P<0.01,OR=0.888,95%CI:0.828-0.958)was an independent risk factor for overall ***,multivariate analysis revealed that BMI(P<0.01,OR=1.176,95%CI:1.041-1.330)and time from primary surgery to ileostomy reversal(P<0.01,OR=1.140,95%CI:1.038-1.252)were independent risk factors for stoma-related compl

关键词： Ileostomy Reversal Risk factors Complications Rectal cancer

Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： Cheng zheng li Yang Yunbing Wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high *** valve replacement surgery has been recognized as golden standard for the treatment of *** to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of ***,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune *** prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of *** this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

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双层耦合介质中四边形图灵斑图的数值研究

物理学报 2019年第6期68卷 224-230页

作者：李新政白占国李燕河北科技大学理学院石家庄050018

采用双层线性耦合Lengyel-Epstein模型,在二维空间对简单正四边和超点阵四边形进行了数值分析.结果表明:当两子系统波数比N>1时,随耦合强度的增大,基模的波矢空间共振形式发生改变,系统由简单六边形自发演化为结构复杂的新型斑图,除已... 详细信息

采用双层线性耦合Lengyel-Epstein模型,在二维空间对简单正四边和超点阵四边形进行了数值分析.结果表明:当两子系统波数比N>1时,随耦合强度的增大,基模的波矢空间共振形式发生改变,系统由简单六边形自发演化为结构复杂的新型斑图,除已报道的超六边形外,还获得了简单正四边和多种超点阵四边形,包括大小点、点线、白眼和环状超四边等斑图.当耦合系数α和β在一定范围内同步增大时,两子系统形成相同波长的Ⅰ型简单正四边;当α和β不同步增大时,由于两图灵模在短波子系统形成共振,系统斑图经相变发生Ⅰ型正四边→Ⅱ型正四边→超点阵四边形的转变;当系统失去耦合作用时,短波子系统波长为λ的Ⅰ型正四边斑图迅速失稳并形成波长为λ/N的Ⅰ型正四边,随模拟时间的延长,两子系统中不同波长的正四边均会经相变发生Ⅰ型正四边→Ⅱ型正四边→六边形的转变.

关键词： Lengyel-Epstein模型超点阵四边形图灵失稳

Flexible sensors with zero Poisson's ratio

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National Science Review 2024年第5期11卷 153-169页

作者： xin Huang Tianzhao Bu Qingyang zheng Shaoyu liu Yangyang li Han Fang Yuqi Qiu Bin Xie Zhouping Yin Hao Wu Department of Mechanical Engineering Flexible Electronics Research Center State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and Technology Department of Electronic Science and Technology School of Integrated CircuitsHuazhong University of Science and Technology

Flexible sensors have been developed for the perception of various stimuli. However, complex deformation,usually resulting from forces or strains from multi-axes, can be challenging to measure due to the lack of independent perception of multiaxial stimuli. Herein, flexible sensors based on the metamaterial membrane with zero Poisson's ratio(ZPR) are proposed to achieve independent detection of biaxial stimuli. By deliberately designing the geometric dimensions and arrangement parameters of elements, the Poisson's ratio of an elastomer membrane can be modulated from negative to positive, and the ZPR membrane can maintain a constant transverse dimension under longitudinal stimuli. Due to the accurate monitoring of grasping force by ZPR sensors that are insensitive to curvatures of contact surfaces, rigid robotic manipulators can be guided to safely grasp deformable objects. Meanwhile, the ZPR sensor can also precisely distinguish different states of manipulators. When ZPR sensors are attached to a thermal-actuation soft robot, they can accurately detect the moving distance and direction. This work presents a new strategy for independent biaxial stimuli perception through the design of mechanical metamaterials, and may inspire the future development of advanced flexible sensors for healthcare, human–machine interfaces and robotic tactile sensing.

关键词： zero Poisson's ratio metamaterials independent perception of multiaxial stimuli flexible sensor

A CNN-SVR model for NO_(2)profile prediction based on MAX-DOAS observations:The influence of Chinese New Year overlapping the 2020 COVID-19 lockdown on vertical distributions of tropospheric NO_(2)in Nanjing,China

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Journal of Environmental Sciences 2024年第7期141卷 151-165页

作者： xin Tian Zijie Wang Pinhua Xie Jin Xu Ang li Yifeng Pan Feng Hu Zhaokun Hu Mingsheng Chen Jiangyi zheng Information Materials and Intelligent Sensing Laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Key laboratory of Environmental Optical and Technology Anhui Institute of optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China

In this study,a hybrid model,the convolutional neural network-support vector regression model,was adopted to achieve prediction of the NO_(2)profile in Nanjing from January 2019to March *** the sudden decline in NO_(2)in February 2020,the contribution of the Coronavirus Disease-19(COVID-19)lockdown,Chinese New Year(CNY),and meteorologi cal conditions to the reduction of NO_(2)was ***_(2)vertical column densities(VCDs) from January to March 2020 decreased by 59.05%and 32.81%,relative to the same period in 2019 and 2021,*** the period of 2020 COVID-19,the average NO_(2)VCDs were 50.50%and 29.96%lower than those during the pre-lockdown and post-lockdown pe riods,*** NO_(2)volume mixing ratios(VMRs)during the 2020 COVID-19 lock down significantly decreased below 400 *** NO_(2)VMRs under the different wind fields were significantly lower during the lockdown period than during the pre-lockdown period This phenomenon could be attributed to the 2020 COVID-19 *** NO_(2)VMRs be fore and after the CNY were significantly lower in 2020 than in 2019 and 2021 in the same period,which further proves that the decrease in NO_(2)in February 2020 was attributed to the COVID-19 *** source analysis of an NO_(2)pollution episode during the lockdown period showed that the polluted air mass in the Beijing-Tianjin-Hebei was trans ported southwards under the action of the north wind,and the subsequent unfavorable meteorological conditions(local wind speed of<2.0 m/sec)resulted in the accumulation o pollutants.

关键词： MAX-DOAS CNN-SVR Nitrogen dioxide COVID-19 Chinese New Year Regional transport

The on-chip thermoelectric cooler:advances,applications and challenges

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Chip 2024年第2期3卷 96-108页

作者： Chengjun li Yubo Luo Wang li Boyu Yang Chengwei Sun Wenyuan Ma zheng Ma Yingchao Wei xin li Junyou Yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

With the development of 5G technology and increasing chip integration,traditional active cooling methods struggle to meet the growing thermal demands of *** coolers(TECs)have garnered great attention due to their rapid response,significant cooling differentials,strong compatibility,high stability and controllable device *** this review,starting from the fundamental principles of thermoelectric cooling and device design,high-performance thermoelectric cooling materials are summarized,and the progress of advanced on-chip TECs is comprehensively ***,the paper outlines the challenges and opportunities in TEC design,performance and applications,laying great emphasis on the critical role of thermoelectric cooling in addressing the evolving thermal management requirements in the era of emerging chip technologies.

关键词： Chip Thermal management Thermoelectric materials Thermoelectric cooler Cooling performance

Mechanochemical route to fabricate an efficient nitrate reduction electrocatalyst

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Nano Research 2024年第6期17卷 4889-4897页

作者： Yunliang liu Zhiyu zheng Sobia Jabeen Naiyun liu Yixian liu Yuanyuan Cheng Yaxi li Jingwen Yu xin Wu Nina Yan Lei Xu Haitao li Institute for Energy Research School of Energy and Power EngineeringJiangsu UniversityZhenjiang 212013China Jiangsu Engineering Technology Research Center of Biomass Composites and Addictive Manufacturing Institute of Agricultural Facilities and EquipmentJiangsu Academy of Agricultural SciencesNanjing 210014China Key Laboratory for Protected Agricultural Engineering in the Middle and Lower Reaches of Yangtze River Ministry of Agriculture and Rural AffairsNanjing 210014China

The electrochemical nitrate reduction reaction(NO_(3)RR)to ammonia under ambient conditions is a promising approach for addressing elevated nitrate levels in water bodies,but the progress of this reaction is impeded by the complex series of chemical reactions involving electron and proton transfer and competing hydrogen evolution ***,it becomes imperative to develop an electro-catalyst that exhibits exceptional efficiency and remarkable selectivity for ammonia synthesis while maintaining long-term *** the magnetic biochar(Fe-C)has been synthesized by a two-step mechanochemical route after a pyrolysis treatment(450,700,and 1000℃),which not only significantly decreases the particle size,but also exposes more oxygen-rich functional groups on the surface,promoting the adsorption of nitrate and water and accelerating electron transfer to convert it into *** showed that the catalyst(Fe-C-700)has an impressive NH_(3)production rate of 3.5 mol·h^(−1)·gcat^(−1),high Faradaic efficiency of 88%,and current density of 0.37 A·cm^(−2)at 0.8 V *** hydrogen electrode(RHE).In-situ Fourier transform infrared spectroscopy(FTIR)is used to investigate the reaction intermediate and to monitor the *** oxygen functionalities on the catalyst surface activate nitrate ions to form various intermediates(NO_(2),NO,NH_(2)OH,and NH_(2))and reduce the rate determining step energy barrier(*NO_(3)→*NO_(2)).This study presents a novel approach for the use of magnetic biochar as an electro-catalyst in NO_(3)RR and opens the road for solving environmental and energy challenges.

关键词： mechanochemical route magnetic biochar electron transfer nitrate ammonia

An Example of Embedded Singular Continuous Spectrum for Discrete Schrödinger Operators

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1837-1849页

作者： zheng Qi FU Xiong li Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

We present an example of a potential such that the corresponding discrete Schrödinger operator has singular continuous spectrum embedded in the absolutely continuous spectrum.

关键词： Sparse potentials singular continuous spectrum Prüfer variables