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Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand

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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： Pei-Yu Liao Yu-quan qi Zhen Li Jian-Hua Jia Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under UV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

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Structure,electronic,and nonlinear optical properties of superalkaline M_(3)O(M=Li,Na)doped cyclo[18]carbon

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Chinese Physics B 2024年第2期33卷 311-317页

作者：刘晓东卢其亮罗其全 School of Physics and Material Science Anhui UniversityHefei 230601China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China

Cyclo[18]carbon has received considerable attention thanks to its novel geometric configuration and special electronic *** have low ionization *** a superalkali in cyclo[18]carbon is an effective method to improve the optical properties of the system because considerable electron transfer *** this paper,the geometry,bonding properties,electronic structure,absorption spectrum,and nonlinear optical(NLO)properties of superalkaline M_(3)O(M=Li,Na)-doped cyclo[18]carbon were studied by using density functional theory.M_(3)O and the C_(18) rings are not *** C_(18) ring still exhibits alternating long and short *** charge transfer between M_(3)O and C_(18) forms stable[M_(3)O]+[C_(18)]-ionic complexes.C_(18)M_(3)O(M=Li,Na)shows striking optical nonlinearity,i.e.,their first-and second-order hyperpolarizability(βvec andγ||)increase considerably atλ=1907 nm and 1460 nm.

关键词： superalkaline doped cyclocarbon structure and electronic properties nonlinear optical properties density functional theory(DFT)

Klebsiella pneumoniae infections after liver transplantation:Drug resistance and distribution of pathogens,risk factors,and influence on outcomes

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World Journal of Hepatology 2024年第4期16卷 612-624页

作者： Long Guo Peng Peng Wei-Ting Peng Jie Zhao qi-quan Wan Department of Respiratory and Critical Care Medicine The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina Clinical Laboratory Medicine Center Zhuzhou Hospital Affiliated to Xiangya School of MedicineCentral South UniversityZhuzhou 421007Hunan ProvinceChina The Second Affiliated Hospital Class Xiangya School of MedicineCentral South UniversityChangsha 410013Hunan ProvinceChina Department of Liver Surgery Renji HospitalShanghai Jiaotong University School of MedicineShanghai 200127China Department of Transplant Surgery The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina Engineering and Technology Research Center for Transplantation Medicine of National Health Commission The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina

BACKGROUND Liver transplantation(LT)is the only curative treatment for end-stage liver ***,LT recipients are susceptible to infection,which is the leading cause of early mortality after *** pneumoniae infections(KPIs)in the bloodstream are common in LT *** hypothesized that KPIs and carbapenemresistant Klebsiella pneumoniae(CRKP)infections may affect the outcomes of LT *** To assess KPI incidence,timing,distribution,drug resistance,and risk factors following LT and its association with *** This retrospective study included 406 patients undergoing LT at The Third Xiangya Hospital of Central South University,a tertiary hospital,from January 2015 to January *** investigated the risk factors for KPIs and assessed the impact of KPIs and CRKP infections on the prognosis of LT recipients using logistic regression *** KPI incidence was 7.9%(n=32),with lung/thoracic cavity the most frequent site of infection;the median time from LT to KPI onset was 7.5 *** 44 Klebsiella pneumoniae isolates,43(97.7%)and 34(77.3%)were susceptible to polymyxin B or ceftazidime/avibactam and tigecycline,respectively;>70%were resistant to piperacillin/tazobactam,ceftazidime,cefepime,aztreonam,meropenem,and *** sex[odds ratio(OR)=2.827,95%confidence interval(CI):1.256-6.364;P=0.012],pre-LT diabetes(OR=2.794,95%CI:1.070-7.294;P=0.036),day 1 post-LT alanine aminotransferase(ALT)levels≥1500 U/L(OR=3.645,95%CI:1.671-7.950;P=0.001),and post-LT urethral catheter duration over 4 d(OR=2.266,95%CI:1.016-5.054;P=0.046)were risk factors for *** infections,but not KPIs,were risk factors for 6-month all-cause mortality *** KPIs occur frequently and rapidly after *** factors include female sex,pre-LT diabetes,increased post-LT ALT levels,and urethral catheter *** infections,and not KPIs,affect mortality.

关键词： Liver transplantation Klebsiella pneumoniae infections Carbapenem-resistant Klebsiella pneumoniae Risk factors Outcomes

Nomogram to predict gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions:Clinical significance

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World Journal of Gastrointestinal Endoscopy 2024年第1期16卷 5-10页

作者： Xu-Peng Wen qi-quan Wan Department of Critical Care Medicine Zhongshan HospitalFudan UniversityShanghai 200030China Department of Transplant Surgery The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina

Transoral endoscopic resections in treating upper gastrointestinal submucosal lesions have the advantages of maintaining the integrity of the gastrointestinal lumen,avoiding perforation and reducing gastrointestinal *** are becoming more widely used in clinical practice,but,they may also present a variety of ***-related complications are one of the most common,which can be left untreated if the symptoms are mild,but in severe cases,they can lead to rapid changes in the respiratory and circulatory systems in a short period,which can be ***,it is important to predict the occurrence of gas-related complications early and take preventive measures *** on the authors'results in the prepublication of the article“Nomogram to predict gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions,”and in conjunction with our evaluation and additions to the relevant content,radiographs may help screen patients at high risk for gas-related *** blood glucose levels,shortening the duration of surgery,and choosing the most appropriate surgical resection may positively impact the prognosis of patients at high risk for gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions.

关键词： Complications Endoscopy Upper gastrointestinal tract Nomogram Clinical significance

Diagnostic value of serum vascular endothelial growth factor and interleukin-17 in primary hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2024年第9期16卷 2934-2941页

作者： qi Tian Hui Zeng qi-quan Lu Hai-Ying Xie Yong Li Clinical Laboratory Hanyang Hospital Affiliated to Wuhan University of Science and Technology/Wuhan Hanyang HospitalWuhan 430050Hubei ProvinceChina Clinical Laboratory Wuhan Seventh HospitalWuhan 430071Hubei ProvinceChina Department of Oncology Hematology Hanyang Hospital Affiliated to Wuhan University of Science and TechnologyWuhan 430050Hubei ProvinceChina

BACKGROUND Despite significant advancements in the medical treatment of primary hepato-cellular carcinoma(PHC)in recent years,enhancing therapeutic effects and im-proving prognosis remain substantial challenges *** To investigate the expression levels of serum vascular endothelial growth factor(VEGF)and interleukin(IL)-17 in patients with PHC and evaluate their diagnostic value while exploring their relationship with patients’clinical *** The study included 50 patients with confirmed PHC who visited Wuhan Han-yang Hospital from January 2021 to January 2022,and 50 healthy individuals from the same period served as the control *** VEGF and IL-17 levels in both groups were measured by Enzyme-Linked Immunosorbent Assay,and their diagnostic value was assessed using receiver operating characteristic(ROC)*** correlation analysis was performed to examine the relationship between serum VEGF and IL-17 *** data of the PHC patients were analyzed to determine the relationship between serum VEGF and IL-17 levels and pathological *** Serum VEGF and IL-17 levels were significantly higher in the study group com-pared to the control group(P0.05).However,there was a significant relationship between clinical TNM stage,tumor metastasis,and serum VEGF and IL-17 levels(P<0.05).Correlation analysis revealed a positive correlation between serum VEGF and IL-17(P<0.05).ROC analysis demonstrated that both serum VEGF and IL-17 had good diagnostic efficacy for *** Serum VEGF and IL-17 levels were significantly higher in PHC patients compared to healthy *** levels were closely related to pathological features such as tumor metastasis and clinical TNM stage,and there was a significant positive correlation between VEGF and IL-17.T

关键词： Primary liver cancer Vascular endothelial growth factor Interleukin-17 Serum level Diagnostic value Cor-relation

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农产品国际贸易新格局形成中的中国因素

华南农业大学学报（社会科学版） 2024年第3期23卷 78-93页

作者：熊启泉喻美辞华南农业大学广东农村经济研究中心广东广州510642

与2000年相比,2021年农产品国际贸易的产品集中度和国别集中度双双下降,发展中经济体扮演了更重要的角色。实证研究表明:从2000年到2021年,中国是全球农产品国际贸易新格局形成的重要推动力量。中国对全球农产品国际贸易规模增量的贡献... 详细信息

与2000年相比,2021年农产品国际贸易的产品集中度和国别集中度双双下降,发展中经济体扮演了更重要的角色。实证研究表明:从2000年到2021年,中国是全球农产品国际贸易新格局形成的重要推动力量。中国对全球农产品国际贸易规模增量的贡献为9.45%,降低了可贸易农产品的产品集中度和地理集中度,重构了全球农产品国际贸易的地理方向,提高了发展中国家在农产品国际贸易中的地位。另外,中国践行“确保谷物基本自给、口粮绝对安全”的新粮食安全观,遏制了谷物进口的过快增长,从而对稳定谷物国际贸易格局、维护世界粮食安全发挥了重要作用。

关键词：农产品国际贸易粮食安全比较优势中国因素

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玻纤增强聚丙烯热管理系统基板模流分析优化

塑料科技 2024年第1期52卷 107-111页

作者：齐栋泉西安工业大学计算机科学与工程学院陕西西安710021

文章基于仿真技术模拟了某玻纤增强热管理系统基板的注塑成型过程,以此评估可行性及优化方案。通过分析填充阻力及浇口匹配性结果确定了最佳的进胶方案。采用初始工艺计算得到基板的定位孔变形极差为0.538 4 mm,达不到设计指标要求。以... 详细信息

文章基于仿真技术模拟了某玻纤增强热管理系统基板的注塑成型过程,以此评估可行性及优化方案。通过分析填充阻力及浇口匹配性结果确定了最佳的进胶方案。采用初始工艺计算得到基板的定位孔变形极差为0.538 4 mm,达不到设计指标要求。以注射时间、保压时间、模腔温度及熔料温度为变量设计正交试验并进行分析。结果表明:保压时间和注射时间的影响为极显著;模腔温度的影响为显著,而熔料温度的影响不显著。优化的工艺参数组合为A_(2)B_(2)C_(1)D_(3)。优化工艺的仿真结果显示:定位孔变形极差为0.452 8 mm,下降了15.9%,且达到设计指标要求;填状态良好、无缺欠注和滞留。实际试模样品的外观良好、变形结果均合格,验证了优化工艺的正确性。

关键词：热管理系统基板仿真计算正交试验参数优化

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“生物个体”概念的分析与界定

自然辩证法研究 2024年第6期40卷 30-35,61页

作者：万小龙徐亮桂起权电子科技大学马克思主义学院成都611731 河南师范大学政治与公共管理学院新乡453007 武汉大学哲学学院武汉430072

生物世界是由个体组成的,但(生物)个体是一个有待分析的概念。它并不等同于我们通常所说的生物体,而是一个包含多层级结构、多个体性的综合概念。生物个体按照层级可划分为基因个体、细胞个体、生物体个体、群组个体和物种个体,而按照... 详细信息

生物世界是由个体组成的,但(生物)个体是一个有待分析的概念。它并不等同于我们通常所说的生物体,而是一个包含多层级结构、多个体性的综合概念。生物个体按照层级可划分为基因个体、细胞个体、生物体个体、群组个体和物种个体,而按照个体性又可划分为进化个体、生理个体、遗传个体、功能个体和发育个体等。此外对生物个体的界定还应考虑其时空维度、生化规律,将其看作统一的单元、完整的单元。

关键词：生物学哲学生物个体生物体多元主义生物体中心

ChatGPT背景下教师的角色价值及其实现

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教育理论与实践 2024年第23期44卷 32-36页

作者：蔡其全张兰婷潘理平山东省教育科学研究院山东济南250000 泰山学院教师教育学院山东泰安271000 湖北科技学院教育学院湖北咸宁437100

ChatGPT作为一种全新的生成式人工智能技术,不仅能高效履行知识教学职能,还能够开展创造性教学,并且依照社会要求遵循特定的伦理规范,一定程度上具备某种“师者”特质。教育作为专门培养人的场域,教师角色所具有的源于本真理解的创造性... 详细信息

ChatGPT作为一种全新的生成式人工智能技术,不仅能高效履行知识教学职能,还能够开展创造性教学,并且依照社会要求遵循特定的伦理规范,一定程度上具备某种“师者”特质。教育作为专门培养人的场域,教师角色所具有的源于本真理解的创造性、基于伦理抉择的自主判断性、衷于卓越人性培育的价值追求,人工智能产品远无法比拟和取代。在推动ChatGPT助力课堂教学的基础上,需要重新审视教师的角色价值,以更好地实现人机协同。教师在教学中要做到重视非理性因素,参与多样化教学情境;增加相关情境体验,直面复杂的道德实践;秉持教学价值自觉,探索新型的育人方式。

关键词： ChatGPT 教师角色创造性自主判断性目的性教学情境道德实践价值自觉

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