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Stereoselective synthesis of substituted 1,3-dienes from propargylic esters: electrophilic-metal or redox catalysis?

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Science China Chemistry 2024年第5期67卷 1384-1396页

作者： Mengfu Dai liangliang Song liang-An chen jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

1,3-Diene architectures are not only widely present in natural products, pharmaceuticals, and functional organic materials but also serve as versatile building blocks to furnish important functionalized molecules in synthetic chemistry due to conjugated repeating C=C units. Accordingly, various strategies to access substituted 1,3-dienes in a stereoselective manner have been developed. However, chemo-, regio-and stereoselective synthesis of highly substituted 1,3-dienes still remains elusive and challenging. Readily available propargylic esters have emerged as an appealing class of synthetic intermediates for accessing functionalized 1,3-dienes, especially challenging tri-or tetrasubstituted variants, via transition-metal catalysis, including electrophilic metal and redox neutral catalysis. This review, for the first time, systematically highlights recent advances in transitionmetal catalyzed synthesis of substituted 1,3-dienes from propargylic esters, discusses the mechanisms and synthetic utilities, and gives the remaining challenges and potential opportunities in this field.

关键词： 1 3-diene propargylic ester Lewis acid redox catalysis transition metal

From dichotomy to diversity:deciphering the multifaceted roles of tumor-associated macrophages in cancer progression and therapy

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Cancer Biology & Medicine 2024年第2期21卷 132-138页

作者： Xiumei Wang Jun chen Guangshuai jia Department of Immunology and Microbiology Zhongshan School of MedicineSun Yat-sen UniversityGuangzhou 510080China Jinfeng Laboratory Chongqing 401329China GMU-GIBH Joint School of Life Sciences Guangzhou Medical UniversityGuangzhou 510182China

Macrophages are innate immune cells that are ubiquitously distributed throughout the vertebrate *** orchestrate sophisticated processes in development,homeostasis,immunity,and *** residing in tumor tissues are commonly known as tumor-associated macrophages(TAMs)and promote or inhibit tumor growth depending on the activation state2.

关键词： immunity homeostasis tumor

Event-triggered predefined-time control for full-state constrained nonlinear systems: A novel command filtering error compensation method

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Science China(Technological Sciences) 2024年第9期67卷 2867-2880页

作者： PAN YingNan chen YiLin liang HongJing College of Control Science and Engineering Bohai UniversityJinzhou 121013China School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing 100089China

In this paper, a command filter-based adaptive fuzzy predefined-time event-triggered tracking control problem is investigated for uncertain nonlinear systems with time-varying full-state constraints. By designing a sliding mode differentiator, the inherent computational complexity problem within the predefined-time backstepping framework is solved. Different from the existing command filter-based finite-time and fixed-time control strategies that the convergence time of the filtering error is adjusted through the system initial value or numerous parameters, a novel command filtering error compensation method is presented,which tunes one control parameter to make the filtering error converge in the predefined time, thereby reducing the complexity of design and analysis of processing the filtering error. Then, an improved event-triggered mechanism(ETM) that builds upon the switching threshold strategy, in which an inverse cotangent function is designed to replace the residual term of the ETM,is proposed to gradually release the controller's dependence on the residual term with increasing time. Furthermore, a tan-type nonlinear mapping technique is applied to tackle the time-varying full-state constraints problem. By the predefined-time stability theory, all signals in the uncertain nonlinear systems exhibit predefined-time stability. Finally, the feasibility of the proposed algorithm is substantiated through two simulation results.

关键词： predefined-time control command filtering error compensation method event-triggered mechanism time-varying full-state constraints uncertain nonlinear systems

Tailoring microenvironment for efficient CO_(2)electroreduction through nanoconfinement strategy

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Nano Research 2024年第9期17卷 7880-7899页

作者： Lulu chen Minhan Li jia-Nan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation Country College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

The electrocatalytic conversion of CO_(2)to produce fuels and chemicals holds great promise,not only to provide an alternative to fossil feedstocks,but also to use renewable electricity to convert and recycle the greenhouse gas CO_(2)to mitigate climate ***,the selectivity and reaction rates for the conversion of CO_(2)into desirable carbon-based products,especially multicarbon products with high added value,are still insufficient for commercial applications,which is attributed to insufficiently favourable microenvironmental conditions in the vicinity of the *** construction of catalysts/electrodes with confined structures can effectively improve the reaction microenvironment in the vicinity of the electrodes and thus effectively direct the reaction towards the desired *** this review,we firstly introduce the effects of the microenvironment at the electrode-electrolyte interface including local pH,local intermediate concentration,and local cation concentration on CO_(2)reduction reaction(CO_(2)RR)as well as the mechanism of action,and then shed light on the microenvironmental modulation within the confined space,and finally and most importantly,introduce the design strategy of CO_(2)RR catalyst/electrode based on the confinement effect.

关键词： CO_(2)reduction reaction microenvironment confinement effect catalyst design

Viral hepatitis E:Clinical manifestations,treatment,and prevention

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A prognostic four-gene signature and a therapeutic strategy for hepatocellular carcinoma:Construction and analysis of a circRNA-mediated competing endogenous RNA network

肝脏研究（英文） 2024年第1期8卷 11-21页

作者： Qiumin Luo jia chen Yeqiong Zhang Wenxiong Xu Ying Liu Chan Xie liang Peng Department of Infectious Disease The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina Guangdong Key Laboratory of Liver Disease Research The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongChina

Hepatitis E is a globally distributed infection that varies in seroprevalence between developed and developing *** the less developed regions of Asia and Africa,a high seropositivity rate has been reported for hepatitis E virus(HEV)*** acute hepatitis E is often self-limited and has a favorable prognosis,some populations experience severe manifestations,which may progress to liver ***,some immunocompromised patients are at risk of developing chronic HEV infection and *** screening,reducing misdiagnosis,improving patient management,timely anti-viral therapy for severe and chronic cases,and vaccination of high-risk groups are important measures to reduce the morbidity of hepatitis *** review focused on the clinical presentation,management,and prevention of hepatitis E.

关键词： Hepatitis E Chronic hepatitis Screening Antiviral therapy Vaccination

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 272-287页

作者： Hai-Yan Zhang jia-Jie Zhu Zong-Ming Liu Yu-Xuan Zhang jia-jia chen Ke-Da chen Zhejiang Chinese Medical University Hangzhou 310053China Shulan International Medical College Zhejiang Shuren UniversityHangzhou 310015China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesNational Medical Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China

Background:Hepatocellular carcinoma(HCC)has a poor long-term *** competition of circular RNAs(circRNAs)with endogenous RNA is a novel tool for predicting HCC *** on the alterations of circRNA regulatory networks,the analysis of gene modules related to HCC is ***:Multiple expression datasets and RNA element targeting prediction tools were used to construct a circRNA-microRNA-mRNA network in *** function,pathway,and protein interaction analyses were performed for the differentially expressed genes(DEGs)in this regulatory *** the proteinprotein interaction network,hub genes were identified and subjected to regression analysis,producing an optimized four-gene signature for prognostic risk stratification in HCC ***-HCC drugs were excavated by assessing the DEGs between the low-and high-risk groups.A circRNA-microRNA-hub gene subnetwork was constructed,in which three hallmark genes,KIF4A,CCNA2,and PBK,were subjected to functional enrichment ***:A four-gene signature(KIF4A,CCNA2,PBK,and ZWINT)that effectively estimated the overall survival and aided in prognostic risk assessment in the The Cancer Genome Atlas(TCGA)cohort and International Cancer Genome Consortium(ICGC)cohort was *** inhibitors,PI3K inhibitors,HDAC inhibitors,and EGFR inhibitors were predicted as four potential mechanisms of drug action(MOA)in high-risk HCC *** analysis has revealed that PBK,CCNA2,and KIF4A play a crucial role in regulating the tumor microenvironment by promoting immune cell invasion,regulating microsatellite instability(MSI),and exerting an impact on HCC ***:The present study highlights the role of the circRNA-related regulatory network,identifies a four-gene prognostic signature and biomarkers,and further identifies novel therapy for HCC.

关键词： Hepatocellular carcinoma circRNA-related ceRNA network Biomarker Least absolute shrinkage and selection operator Bioinformatics

Design of acceleration control schedule for adaptive cycle engine based on direct simulation model

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Chinese Journal of Aeronautics 2024年第6期37卷 307-318页

作者： Keran SONG Linyuan jia Yuchun chen Tian TAN School of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China

To design the optimum acceleration control schedule for the Adaptive Cycle Engine(ACE)in the full flight envelope,this paper establishes a direct simulation model of the ACE transient *** this model,geometric parameters are used to replace the component state *** corresponding relationship between geometric parameters and component state parameters is determined by sensitivity *** geometric variables are controlled when the geometric adjustment speed exceeds the limit,and at the same time the corresponding component state parameters are *** gradient optimization algorism is used to optimize the ground acceleration process of ACE,and the control schedule in terms of operating point of compression components and corrected acceleration rate is used as the full-envelope acceleration control schedule based on the similarity *** acceleration control schedules of the triple-bypass mode and the double-bypass mode are designed in this *** acceleration processes under various flight conditions are simulated using the acceleration control *** with the acceleration process with the linear geometric adjustment schedule,the acceleration performance of ACE is improved by the acceleration control schedule,with the impulse of the acceleration process of the triple-bypass mode being increased by 8.7%-12.3% and the impulse of the double-bypass mode acceleration process being increased by 11.8%-14.1%.

关键词： Adaptive Cycle Engine(ACE) Direct simulation method Acceleration Control schedule Full flight envelope

Heat Transfer Characteristics of a Microchannel Heat Sink with Highly-Dense Micro-Jet Arrays

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Journal of Thermal Science 2024年第3期33卷 1148-1160页

作者： ZHANG Yu chen Xiaoyan MIAO Lin chen liang HOU Yu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China Beijing Aerospace Technology Institute Beijing100083China

This paper proposed a new structure of highly-dense micro-jet arrays for hybrid jet-impingement/microchannel heat sinks(~120 jet per cm^(2) with jet width of 0.35 mm).Parametric study is performed to investigate the influence of structure and flow parameters on the convective heat transfer of water jet cooling in confined *** simulation results show that the optimal jet width,jet spacing and impingement distance are around 0.2 mm,0.2 mm and 0.3 mm,respectively,which can achieve a low thermal resistance as well as a relatively low pressure *** analysis of the heat transfer pathways shows that the micro-fin jet structures can extend the impinging heat transfer area and conduct a considerable proportion of heat,which can reach up to 38.9%with the Reynolds number ranging from 797.1 to *** heat transfer characteristics in the heat sink will shift from impingement dominated heat transfer to the channel-convection dominated heat transfer as the jet impingement distance increases.A correlation is proposed to predict the average Nusselt number on the stagnation area for the heat sink with different structure parameters,and the deviations of predictions from the numerical results are less than 10%.

关键词： hybrid heat sink impingement microchannel thermal management high heat flux

Efficacy and safety of minimally invasive laparoscopic surgery under general anesthesia for ovarian cancer

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World Journal of Clinical Cases 2024年第9期12卷 1569-1577页

作者： Xian Qin chen chen Yang Liu Xian-Hong Hua jia-Yi Li Meng-Jie liang Fang Wu Department of Anesthesiology The First People's Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina Department of Obstetrics and Gynecology The First People's Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina

BACKGROUND Ovarian cancer is one of the most common malignant tumors in female reproductive system in the world,and the choice of its treatment is very important for the survival rate and prognosis of *** open surgery is the main treatment for ovarian cancer,but it has the disadvantages of big trauma and slow *** the continuous development of minimally invasive technology,minimally invasive laparoscopic surgery under general anesthesia has been gradually applied to the treatment of ovarian cancer because of its advantages of less trauma and quick ***,the efficacy and safety of minimally invasive laparoscopic surgery under general anesthesia in the treatment of ovarian cancer are still *** To explore the efficacy and safety of general anesthesia minimally invasive surgery in the treatment of ovarian *** The clinical data of 90 patients with early ovarian cancer in our hospital were analyzed *** to the different surgical treatment methods,patients were divided into study group and control group(45 cases in each group).The study group received minimally invasive laparoscopic surgery under general anesthesia for ovarian cancer,while the control group received traditional open surgery for ovarian *** European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30),clinical efficacy and safety of the two groups were *** The intraoperative blood loss,length of hospital stay,postoperative gas evacuation time,and postoperative EORTC QLQ-C30 score of the study group were significantly better than those of the control group(P<0.05).The incidence of postoperative complications in the study group was significantly lower than in the control group(P<0.05).The two groups had no significant differences in the preoperative adrenocorticotropic hormone(ACTH),androstenedione(AD),cortisol(Cor),cluster of differentiation 3 positive(CD3+),and clu

关键词： Early-stage ovarian cancer Efficacy Minimally invasive Laparoscopy Safety Surgery