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Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： shi-liang xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in hexane.This catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of 20000.Furthermore,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene polymerization.These characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer yield.The resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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Establishment and validation of an adherence prediction system for lifestyle interventions in non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2024年第10期30卷 1393-1404页

作者： Ming-Hui Zeng Qi-Yu shi liang xu Yu-Qiang Mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Gastroenterology Cangzhou People’s HospitalCangzhou 061000Hebei ProvinceChina Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Tianjin Research Institute of Liver Diseases Tianjin 300192China

BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease worldwide,affecting about 1/4th of the global population and causing a huge global economic burden.To date,no drugs have been approved for the treatment of NAFLD,making the correction of unhealthy lifestyles the principle method of treatment.Identifying patients with poor adherence to lifestyle correction and attempting to improve their adherence are therefore very important.AIM To develop and validate a scale that can rapidly assess the adherence of patients with NAFLD to lifestyle interventions.METHODS The Exercise and Diet Adherence Scale(EDAS)was designed based on com-pilation using the Delphi method,and its reliability was subsequently evaluated.Demographic and laboratory indicators were measured,and patients completed the EDAS questionnaire at baseline and after 6 months.The efficacy of the EDAS was evaluated in the initial cohort.Subsequently,the efficacy of the EDAS was internally verified in a validation cohort.RESULTS The EDAS consisted of 33 items in six dimensions,with a total of 165 points.Total EDAS score correlated significantly with daily number of exercise and daily reduction in calorie intake(P500 kacl/d),(sensitivity/specificity was 100.0%/75.8%),while patients score below 97 could nearly rule out the possibility of daily exercise(sensitivity/specificity was 89.5%/44.4%).Total EDAS scores≥116,97-115,and<97 points were indicative of good,average,and poor adherence,respectively,to diet and exercise recommendations.CONCLUSION The EDAS can reliably assess the adherence of patients with NAFLD to lifestyle interventions and have clinical application in this population.

关键词： Fatty liver Lifestyle intervention Behavioral change Patient adherence Compliance

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Mirizzi syndrome:Problems and strategies

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 234-240页

作者： Jun Wu Shuang-Yong Cai xu-liang Chen Zhi-Tao Chen Shao-Hua shi Department of Hepatobiliary and Pancreatic Surgery People’s Hospital of Jiulongpo DistrictChongqing 400050China Department of Hepatobiliary and Pancreatic Surgery Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310003China

Mirizzi syndrome is a serious complication of gallstone disease.It is caused by the impacted stones in the gallbladder neck or cystic duct.One of the features of Mirizzi syndrome is severe inflammation or dense fibrosis at the Calot’s triangle.In our clinical practice,bile duct,branches of right hepatic artery and right portal vein clinging to gallbladder infundibulum are often observed due to gallbladder infundibulum adhered to right hepatic hilum.The intraoperative damage of branches of right hepatic artery occurs more easily than that of bile duct,all of which are hidden pitfalls for surgeons.Magnetic resonance cholangiopancreatography(MRCP)and endoscopic retrograde cholangiopancreatography(ERCP)are the preferable tools for the diagnosis of Mirizzi syndrome.Anterograde cholecystectomy in Mirizzi syndrome is easy to damage branches of right hepatic artery and bile duct due to gallbladder infundibulum adhered to right hepatic hilum.Subtotal cholecystectomy is an easy,safe and definitive approach to Mirizzi syndrome.When combined with the application of ERCP,a laparoscopic management of Mirizzi syndrome by well-trained surgeons is feasible and safe.The objective of this review was to highlight its existing problems:(1)low preoperative diagnostic rate,(2)easy to damage bile duct and branches of right hepatic artery,and(3)high concomitant gallbladder carcinoma.Meanwhile,the review aimed to discuss the possible therapeutic strategies:(1)to enhance its preoperative recognition by imaging findings,and(2)to avoid potential pitfalls during surgery.

关键词： Mirizzi syndrome Bile duct injury Artery injury Surgical treatment Subtotal cholecystectomy

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An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming liang Guangning Li Min xu Junmin Zhao Feng Hao Hongbo shi Northwestern Polytechnical University School of Astronautics Xi’an 710072China China North Industries Group Corporation No 203 Research Institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is proposed.The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application prospect.Firstly,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is constructed.In order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried out.The simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight simulation.Secondly,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy respectively.The intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight parameters.Compared with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability error.The intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid

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Alloy strategy to synthesize Pt-early transition metal oxide interfacial catalysts

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Nano Research 2024年第4期17卷 3390-3397页

作者： shi-Long xu Hang Nan Wanqun Zhang Yue Lin Sheng-Qi Chu Hai-Wei liang Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Metal oxide supported metal catalysts show promising catalytic performance in many industry-relevant reactions.However,the enhancement of performance is often limited by the insufficient metal/metal oxide interface.In this work,we demonstrate a general synthesis of Pt-early transition metal oxide(Pt-MO_(x),M=Ti,Zr,V,and Y)catalysts with rich interfacial sites,which is based on the air-induced surface segregation and oxidation of M in the supported Pt-M alloy catalysts.Systematic characterizations verify the dynamic structural response of Pt-M alloy catalysts to air and the formation of Pt-MO_(x) catalysts with abundant interfacial sites.The prepared Pt-TiO_(x) interfacial catalysts exhibit improved performance in hydrogenation reactions of benzaldehyde,nitrobenzene,styrene,and furfural,as a result of the heterolytic dissociation of H_(2) at Pt-metal oxide interfacial sites.

关键词： Pt-early transition metal oxide interfacial catalyst alloy oxidation strategy interfacial sites hydrogenation reactions heterolytic dissociation

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Research progress on venous thrombosis development in patients with malignant tumors

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World Journal of Clinical Cases 2024年第11期12卷 1900-1908页

作者： Teng-Fei Wang Qian Chen Jie Deng shi-liang Li Yuan xu Si-Xing Ma Department of Vascular Surgery The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina Department of Organ Transplantation The Affiliated Hospital of Guizhou Medical UniversityGuiyang 550000Guizhou ProvinceChina

The coexistence of venous thromboembolism(VTE)within patients with cancer,known as cancer-associated thrombosis(CAT),stands as a prominent cause of mortality in this population.Over recent years,the incidence of VTE has demonstrated a steady increase across diverse tumor types,influenced by several factors such as patient management,tumor-specific risks,and treatment-related aspects.Furthermore,mutations in specific genes have been identified as potential contributors to increased CAT occurrence in particular cancer subtypes.We conducted an extensive review encompassing pivotal historical and ongoing studies on CAT.This review elucidates the risks,mechanisms,reliable markers,and risk assessment methodologies that can significantly guide effective interventions in clinical practice.

关键词： Malignant tumor Venous thromboembolism Cancer-associated thrombosis Research progress

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HgaNets:Fusion of Visual Data and Skeletal Heatmap for Human Gesture Action Recognition

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Computers, Materials & Continua 2024年第4期79卷 1089-1103页

作者： Wuyan liang Xiaolong xu School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210023China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing210023China

Recognition of human gesture actions is a challenging issue due to the complex patterns in both visual andskeletal features. Existing gesture action recognition (GAR) methods typically analyze visual and skeletal data,failing to meet the demands of various scenarios. Furthermore, multi-modal approaches lack the versatility toefficiently process both uniformand disparate input patterns.Thus, in this paper, an attention-enhanced pseudo-3Dresidual model is proposed to address the GAR problem, called HgaNets. This model comprises two independentcomponents designed formodeling visual RGB (red, green and blue) images and 3Dskeletal heatmaps, respectively.More specifically, each component consists of two main parts: 1) a multi-dimensional attention module forcapturing important spatial, temporal and feature information in human gestures;2) a spatiotemporal convolutionmodule that utilizes pseudo-3D residual convolution to characterize spatiotemporal features of gestures. Then,the output weights of the two components are fused to generate the recognition results. Finally, we conductedexperiments on four datasets to assess the efficiency of the proposed model. The results show that the accuracy onfour datasets reaches 85.40%, 91.91%, 94.70%, and 95.30%, respectively, as well as the inference time is 0.54 s andthe parameters is 2.74M. These findings highlight that the proposed model outperforms other existing approachesin terms of recognition accuracy.

关键词： Gesture action recognition multi-dimensional attention pseudo-3D skeletal heatmap

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A Knowledge-enhanced Two-stage Generative Framework for Medical Dialogue Information Extraction

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Machine Intelligence Research 2024年第1期21卷 153-168页

作者： Zefa Hu Ziyi Ni Jing shi Shuang xu Bo xu School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper focuses on term-status pair extraction from medical dialogues(MD-TSPE),which is essential in diagnosis dia-logue systems and the automatic scribe of electronic medical records(EMRs).In the past few years,works on MD-TSPE have attracted increasing research attention,especially after the remarkable progress made by generative methods.However,these generative methods output a whole sequence consisting of term-status pairs in one stage and ignore integrating prior knowledge,which demands a deeper un-derstanding to model the relationship between terms and infer the status of each term.This paper presents a knowledge-enhanced two-stage generative framework(KTGF)to address the above challenges.Using task-specific prompts,we employ a single model to com-plete the MD-TSPE through two phases in a unified generative form:We generate all terms the first and then generate the status of each generated term.In this way,the relationship between terms can be learned more effectively from the sequence containing only terms in the first phase,and our designed knowledge-enhanced prompt in the second phase can leverage the category and status candidates of the generated term for status generation.Furthermore,our proposed special status"not mentioned"makes more terms available and en-riches the training data in the second phase,which is critical in the low-resource setting.The experiments on the Chunyu and CMDD datasets show that the proposed method achieves superior results compared to the state-of-the-art models in the full training and low-re-sourcesettings.

关键词： Medical dialogue understanding information extraction text generation knowledge-enhanced prompt low-resource setting dataaugmentation

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Research fronts of agriculture in 2023

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 347-354页

作者： Jianxiang xu Yunzhou LI Jie ZHAO liang shi Yinkun YAO Jingyue TANG Science and Technology Journal Center Higher Education Press FASE Editorial Office of Institute for Science and Technology Development China Agricultural University

At the end of 2023, Chinese Academy of Sciences（CAS） and Chinese Academy of Engineering（CAE） successively announced “2023 Research Fronts”[1] and “2023 Engineering Fronts”[2,3], respectively. Among them, agric...

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Molecular analyses display the increasing diversity of Podostemaceae in China

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Plant Diversity 2024年第3期46卷 421-424页

作者： Zhi-Zhong Li Zhun xu Shuang Wu Lang-Xing Yuan Chun-Yu Zou Yan Liu Jian-Yong Lin shi-Chu liang Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541006China Wuhan Botanical Garden Chinese Academy of SciencesWuhan 430074China Sino-Africa Joint Research Center Chinese Academy of SciencesWuhan 430074China Guangxi Association for Science and Technology Nanning 530023China Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural SciencesHaikou 571101China Guangxi Institute of Botany Chinese Academy of SciencesGuilin 541006China Guangxi Forestry Research Institute Nanning 530028China

Podostemaceae(riverweed family),one of the largest aquatic plant families in the world,comprises about 350 species in 51 genera placed in three subfamilies,Podostemoideae,Weddellinoideae,and Tristichoideae(Koi et al.,2022).Most Podostemaceae genera(~38)are monotypic or oligotypic,with a high level of endemism(Koi et al.,2018,2022).Members of Podostemaceae adhere to rocks in fast-flowing rivers,streams,or waterfalls in the subtropics and tropics(Koi et al.,2018).As an adaptation to fastrunning currents,the morphological structure of river-weeds tends to be extremely reduced,including a loss or reduction of primary shoots or roots(Koi and Kato,2007).The vegetative mass of these plants resembles lichens or bryophytes,and are thus known commonly as“dream bryophytes”(Philbrick and Retana,1998).Podostemaceae plants flower when the water level drops during the dry season.In recent years,anthropogenic factors and climate change have severely affected river weed habitats,decreasing populations of these plants.

关键词： roots season habitat

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