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实验室研究与探索 2024年第2期43卷 169-174页

作者：彭宇余世策钱匡亮浙江大学建筑工程学院杭州310058

基于多年实践并辅以学生调查问卷,讨论了3种模式,即教师主导、研究生主导与本科生主导模式的适应性及其优缺点,提出“本科生为中心、教师为辅、研究生支持3种模式综合运用”的多层次实验教学体系与教学思路,并通过引入学生互评因子优化... 详细信息

基于多年实践并辅以学生调查问卷,讨论了3种模式,即教师主导、研究生主导与本科生主导模式的适应性及其优缺点,提出“本科生为中心、教师为辅、研究生支持3种模式综合运用”的多层次实验教学体系与教学思路,并通过引入学生互评因子优化了考核体系。结果表明,该体系丰富了实验实践类课程教学模式,不仅有利于自主探究类创新实验的教学,又能充分利用实验室资源,且最大程度以本科生为中心,提升其创新思维以及动手、团体合作等能力。

关键词：新工科自主探究性创新实验教学模式本科生为中心

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跨境电商出口企业税务风险管理探讨

国际税收 2024年第5期 64-69页

作者：于海峰余锦彦广东财经大学深圳市递四方速递有限公司

跨境电商出口行业快速发展有力地促进了我国外贸出口增长,但跨境电商出口企业在业务持续增长的过程中也面临大量的税务风险。本文主要从货物劳务税、所得税的角度,结合一些国家相关的税收政策,分析跨境电商出口企业可能面临的税务风险点... 详细信息

跨境电商出口行业快速发展有力地促进了我国外贸出口增长,但跨境电商出口企业在业务持续增长的过程中也面临大量的税务风险。本文主要从货物劳务税、所得税的角度,结合一些国家相关的税收政策,分析跨境电商出口企业可能面临的税务风险点,并从主动掌握相关境外税务合规要求、合理规划境外公司开办地点、合理设计交易模式及股权架构等方面提出优化税务风险管理的建议。

关键词：跨境电商出口税务风险管理税收协定税务合规

Prognostic relevance of ventricular arrhythmias in surgical patients with gastrointestinal tumors

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1787-1795页

作者： Jiao-Jie Xue Su-Tian Hu Chong-Chong Wang Zhi-Chong Chen Shi-Yao Cheng Shu-Qi yu Hua-Jing Peng Yi-Tao Zhang Wei-Jie Zeng Department of Cardiovascular Internal Medicine Sun Yat-sen University Sixth Affiliated HospitalGuangzhou 510655Guangdong ProvinceChina Department of Cardiovascular Internal Medicine The Fifth Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510700Guangdong ProvinceChina Department of Ultrasound Fuwai HospitalChinese Academy of Medical Sciences ShenzhenShenzhen 518052Guangdong ProvinceChina Department of Kidney Internal Medicine Sun Yat-sen University First Affiliated HospitalGuangzhou 510062Guangdong ProvinceChina

BACKGROUND Individuals diagnosed with gastrointestinal tumors are at an increased risk of developing cardiovascular *** which,ventricular arrhythmia is a prevalent clinical *** suggests that ventricular arrhythmias may have predictive value in the prognosis of patients with gastrointestinal *** To explore the prognostic value of ventricular arrhythmias in patients with gastrointestinal tumors receiving *** We retrospectively analyzed data from 130 patients undergoing gastrointestinal tumor *** patients were evaluated by a 24-h ambulatory electrocardiogram(ECG)at the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to June ***,41 general healthy age-matched and sexmatched controls were *** were categorized into survival and non-survival *** primary endpoint was all-cause mortality,and secondary endpoints included major adverse cardiovascular events(MACEs).RESULTS Colorectal tumors comprised 90%of *** ambulatory ECG monitoring revealed that among the 130 patients with gastrointestinal tumors,100(76.92%)exhibited varying degrees of premature ventricular contractions(PVCs).Ten patients(7.69%)manifested non-sustained ventricular tachycardia(NSVT).The patients with gastrointestinal tumors exhibited higher PVCs compared to the healthy controls on both conventional ECG[27(21.3)vs 1(2.5),P=0.012]and 24-h ambulatory ECG[14(1.0,405)vs 1(0,6.5),P35/24 h to all-cause mortality,and NSVT was associated with ***,neither PVC burden nor NSVT independently predicted outcomes according to multivariate *** Patients with gastrointestinal tumors exhibited elevated ***>35/24 h and NSVT detected by 24-h ambulatory ECG were prognos

关键词： Ventricular arrhythmia Gastrointestinal tumor Major adverse cardiovascular events Prognostic Surgery

Risk factors associated with intraoperative persistent hypotension in pancreaticoduodenectomy

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1582-1591页

作者： Xing-Jun Wang Xi-Chen Xuan Zhao-Chu Sun Shi Shen Fan yu Na-Na Li Xue-Chun Chu Hui Yin You-Li Hu Department of Anesthesia and Perioperative Medicine The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina

BACKGROUND Intraoperative persistent hypotension(IPH)during pancreaticoduodenectomy(PD)is linked to adverse postoperative outcomes,yet its risk factors remain *** To clarify the risk factors associated with IPH during PD,ensuring patient safety in the perioperative *** A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in *** factors included age,gender,body mass index,American Society of Anesthesiologists classification,comorbidities,medication history,operation duration,fluid balance,blood loss,urine output,and blood gas *** was defined as sustained mean arterial pressure30 min despite additional deoxyepinephrine and fluid *** Among 1596 PD patients,661(41.42%)experienced *** logistic regression identified key risk factors:increased age[odds ratio(OR):1.20 per decade,95%confidence interval(CI):1.08-1.33](P<0.001),longer surgery duration(OR:1.15 per additional hour,95%CI:1.05-1.26)(P<0.01),and greater blood loss(OR:1.18 per 250-mL increment,95%CI:1.06-1.32)(P<0.01).A novel finding was the association of arterial blood Ca^(2+)<1.05 mmol/L with IPH(OR:2.03,95%CI:1.65-2.50)(P<0.001).CONCLUSION IPH during PD is independently associated with older age,prolonged surgery,increased blood loss,and lower plasma Ca^(2+).

关键词： Risk factors Pancreaticoduodenectomy Perioperative period Intraoperative persistent hypotension Retrospective cohort study

Ag_(2)Sb合金单层上多层酞菁氧钒分子的组装

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物理学报 2024年第11期73卷 80-88页

作者：李小雨彭兰沁赵涵幸运邓炎滔于迎辉湖北大学物理学院武汉430062

利用低温扫描隧道显微镜(STM)研究了各种覆盖度下酞菁氧钒(VOPc)分子在Ag_(2)Sb/Ag(111)上的吸附行为和组装结构.不同于Ag(111)表面,当分子覆盖度在一个单层之内,吸附的VOPc分子均组装为有序的薄膜,呈现出规则排列的空隙和正方形单胞.... 详细信息

利用低温扫描隧道显微镜(STM)研究了各种覆盖度下酞菁氧钒(VOPc)分子在Ag_(2)Sb/Ag(111)上的吸附行为和组装结构.不同于Ag(111)表面,当分子覆盖度在一个单层之内,吸附的VOPc分子均组装为有序的薄膜,呈现出规则排列的空隙和正方形单胞.通过扫描亚分子分辨的STM形貌图,揭示了正方形单胞由一个中心分子和四个对称排列的角分子组成;所有VOPc分子均采用O-up构型,并呈现出两种吸附取向,分子横轴相对于单胞侧边分别旋转约11°和21°.因分子间的偶极-偶极相互作用,进一步沉积的VOPc分子组装为具有O-down和O-up构型交替堆积的分子膜,在分子层内分子轨道沿π堆积方向发生重叠.该研究为调控金属表面功能有机分子组装膜的结构和组装行为提供了一种新途径.

关键词：酞菁氧钒扫描隧道显微镜结构方向

Robust output regulation for a class of hyperbolic PDE systems based on DeepONet

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Robust output regulation for a class of hyperbolic PDE syste...

Reproducibility study of intravoxel incoherent motion and apparent diffusion coefficient parameters in normal pancreas

第35届中国过程控制会议

作者： yu Xiao Xiaodong Xu Xunyuan Yin Central South University School of Automation Nanyang Technological University School of Chemistry Chemical Engineering and Biotechnology

Thanks to the global approximation ability of the DeepONet in approximating operators from function spaces to other function spaces, the DeepONet has been employed as a gain solver in the backstepping stabilization control for boundary controllable PDE systems. Prior to the implementation, the DeepONet can be trained offline on a dataset containing a sufficient number of system parameters and correspondingly exact solutions of the kernel equations. Once the DeepONet is well-trained,as a gain solver it can generate approximate gain function with arbitrary accuracy, and more notably the solving time is greatly reduced compared with numerical PDE solver in generating gain function. In this paper, we extend the neural operator（NO）theory to a more complex field of robust regulation control for a class of hyperbolic PDE systems. Although the DeepONet cannot eliminate the approximation error, the regulator designed based on the internal model principle is robust to the error in approximate gain and a certain degree of parameter uncertainty. Therefore, the tracking error can still converge to 0 if the extended regulator equation is solvable. A series of theory proofs of the regulation problem and a numerical test under the approximate gain are presented. It is shown that NO is almost three orders of magnitude faster than PDE solver in generating kernel function, and the loss remains on the order of 10. This provides a new insight to use the NO methodology for accelerated gain scheduling regulation for PDEs with time-varying parameters.

关键词： DeepONet Neural operator Hyperbolic PDE systems Robust output regulation

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2031-2039页

作者： Xiang Liu Yi-Feng Wang Xiao-Hui Qi Zhi-Lei Zhang Jiang-Yang Pan Xue-Li Fan yu Du Ying-Min Zhai Qi Wang Department of CT and MRI The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND The consistency of pancreatic apparent diffusion coefficient(ADC)values and intravoxel incoherent motion(IVIM)parameter values across different magnetic resonance imaging(MRI)devices significantly impacts the patient’s diagnosis and *** To explore consistency in image quality,ADC values,and IVIM parameter values among different MRI devices in pancreatic *** This retrospective study was approved by the local ethics committee,and informed consent was obtained from all *** total,22 healthy volunteers(10 males and 12 females)aged 24-61 years(mean,28.9±2.3 years)underwent pancreatic diffusion-weighted imaging using 3.0T MRI equipment from three *** independent observers subjectively scored image quality and measured the pancreas’s overall ADC values and signal-to-noise ratios(SNRs).Subsequently,regions of interest(ROIs)were delineated for the IVIM parameters(true diffusion coefficient,pseudo-diffusion coefficient,and perfusion fraction)using post-processing *** ROIs were on the head,body,and tail of the *** subjective image ratings were assessed using the kappa consistency *** correlation coefficients(ICCs)and mixed linear models were used to evaluate each device’s quantitative parameter ***,a pairwise analysis of IVIM parameter values across each device was performed using Bland-Altman *** The Kappa value for the subjective ratings of the different observers was 0.776(P0.05),and the ICCs for the ADC values from different devices were 0.870,0.707,and 0.808,respectively(P<0.05).Notably,only a few statistically significant inter-device agreements were observed for different IVIM parameters,and among t

关键词： Intravoxel incoherent motion Pancreas Image quality Consistency test

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页岩油微生物采油菌株筛选与性能评价

应用化工 2024年第4期53卷 753-756,780页

作者：于洋刘琦范煜中国石油大学(北京)非常规油气科学技术研究院油气资源与探测国家重点实验室北京102249 中国石油大学(北京)重质油国家重点实验室北京102249

从页岩油藏中筛选得到了一株产表面活性剂菌株Y2,利用16s rDNA基因测序对其进行鉴定;通过表/界面张力测试,优化菌株的培养条件并考察其在不同pH值、温度和盐浓度下的稳定性;通过FTIR和LC-MS分析表征菌株所产生物表面活性剂的理化性质。... 详细信息

从页岩油藏中筛选得到了一株产表面活性剂菌株Y2,利用16s rDNA基因测序对其进行鉴定;通过表/界面张力测试,优化菌株的培养条件并考察其在不同pH值、温度和盐浓度下的稳定性;通过FTIR和LC-MS分析表征菌株所产生物表面活性剂的理化性质。结果表明:菌株Y2(枯草芽孢杆菌,Bacillus subtilis)在以葡萄糖为碳源、硝酸铵为氮源的培养基中所产生物表面活性剂表面活性最优,菌株上清液的表面张力值27.61 mN/m,与页岩油JHW151和JHW07121之间的界面张力值分别为0.062 mN/m和0.047 mN/m。该菌株所产生物表面活性剂为C_(15)-Surfactin和C_(16)-Fengycin的脂肽混合物,其表面活性在温度为40~80℃和pH值为1~11范围内稳定性较好,但随着NaCl浓度的增加界面张力值变小。可见,Y2菌株具有较好的表面活性,能够有效降低油/水界面张力从而提高页岩油采收率,为吉木萨尔页岩油微生物驱的高效开发提供了一项潜在可行的技术路线。

关键词：提高采收率页岩油生物表面活性剂脂肽

BaTiO_(3)优化制备及压电催化性能分析的综合实验设计

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实验室研究与探索 2024年第3期43卷 28-31页

作者：于玲白航陈瑜广东工业大学分析测试中心广州510006

为了实现前沿压电催化水污染控制技术、大型仪器分析技术与实践操作能力培养的有机结合,设计了一个综合水污染控制工程实验——BaTiO_(3)优化制备及压电催化性能分析。通过对BaTiO_(3)进行不同时间的热处理,有效优化BaTiO_(3)压电催化... 详细信息

为了实现前沿压电催化水污染控制技术、大型仪器分析技术与实践操作能力培养的有机结合,设计了一个综合水污染控制工程实验——BaTiO_(3)优化制备及压电催化性能分析。通过对BaTiO_(3)进行不同时间的热处理,有效优化BaTiO_(3)压电催化降解染料性能。利用电子顺磁共振波谱仪(ESR)分析降解过程中自由基的生成,并借助猝灭实验明确不同自由基在染料降解过程中的作用。结果表明,对BaTiO_(3)进行2 h热处理可有效提高其压电催化降解罗丹明B(RhB)染料的性能。ESR检测分析反应体系能产生羟基自由基、单线态氧和超氧自由基,而猝灭实验结果表明羟基自由基在染料降解过程中起主导作用。

关键词：压电催化水污染控制实验综合实验设计