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Chinese Chemical Letters 2013年第7期24卷 553-558页

作者： Hong-jun Yang fang-jun xiong Jie Li Fen-Er Chen Department of Chemistry Fudan University Institute of Biomedical Science Fudan University

A family of novel squaramides/sulfamides based on 1,2-alkamine was developed as chiral bifunctional catalysts to promote the asymmetric alcoholysis of meso cyclic anhydrides. The hemiesters were obtained in high yield with up to 93% ee. The usefulness of this methodology was demonstrated in the asymmetric synthesis of the key intermediate of P2X7 receptor antagonists.

关键词： Asymmetric alcoholysis Bifunctional organocatalyst Cyclic anhydrides P2X7 receptor antagonists Sulfamides

Impact of atmospheric circulations on droughts and drought propagation over China

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Science China Earth Sciences 2024年第8期67卷 2633-2648页

作者： Ziye GU Lei GU Jiabo YIN Wei fang Lihua xiong jun GUO Ziyue ZENG jun XIA School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Water Resources Engineering and Management Wuhan 430072China Changjiang River Scientific Research Institute Wuhan 430010China

The GRACE satellite mission provides a new approach for monitoring,tracking,and assessing drought conditions by detecting changes in Earth's gravitational fields and inversing signals of terrestrial water storage *** studies of terrestrial water storage anomalies related droughts paid rare attention to the behind atmospheric physical mechanisms,nor quantified the risk propagation patterns between terrestrial water storage deficits and hydrological or agricultural *** this study,we first extract terrestrial water storage(TWS) droughts,hydrological droughts,and agricultural droughts by using multiple variables including TWS from the GRACE/GRACE-FO satellites,runoff and soil moisture from the ERA5-Land reanalysis *** then identify key atmospheric and oceanic oscillation indices affecting water deficits by employing machine learning *** characterize the joint distributions between drought duration and severity by using the Copula function and quantify the risk propagation of hydrological and agricultural droughts to TWS *** results show that:(1) From 2002 to 2021,there is a significant decrasing trend of TWS in China;the WPIO group atmospheric circulation indices(sea surface temperature index within the Western Pacific and Indian Ocean) contributes the most to ***,the sea surface temperature anomalies within the NINO 3.4 region as well as the Western Pacific Warm Pool area index show significantly positive correlation relationships with TWS in southern China;(2) The northwestern China,the Yangtze River basin,and the downstream of the Pearl River basin are the hotspots of TWS ***,the hotspots of hydrological droughts locate in northwestern China and the hotspots of agricultural droughts locate in South China and eastern Tibetan Plateau;(3) The elastic coefficients of hydrological droughts propagating to TWS droughts are higher than those of agricultural droughts,indicating that the TWS droughts

关键词： GRACE satellites Drought Drought propagation Atmospheric circulation Copula function

Fast charge transfer kinetics in Sv-ZnIn_(2)S_(4)/Sb_(2)S_(3)S-scheme heterojunction photocatalyst for enhanced photocatalytic hydrogen evolution

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Rare Metals 2024年第2期43卷 533-542页

作者： Wei Li Jia-jun Li Zhi-Fei Liu Hong-Yu Ma Peng-Fei fang Rui xiong Jian-Hong Wei Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan430072China

Constructing a S-scheme heterojunction with tight interface contact and fast charge transfer is beneficial to improving the photocatalytic hydrogen evolution ***,a unique one-dimensional(1D)/two-dimensional(2D)S-scheme heterojunction containing 1D Sb_(2)S_(3) nanorods and 2D ZnIn_(2)S_(4) with affluent sulfur vacancies(denoted as Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3)) was *** introduced sulfur vacancy can promote the effective adsorption of H+for the following interfacial hydrogen-evolution ***,the larger contact area and stronger electron interaction between Sb_(2)S_(3) and ZnIn_(2)S_(4) effectively inhibits the recombination of photo-generated electron–hole pairs and abridges the migration distance of *** a result,the optimal Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) sample achieves H_(2) evolution activity of 2741.3 mol·h^(−1)·g^(−1),which is 8.6 times that of pristine ZnIn_(2)S_(4) and 3.0 times that of the Sv-ZnIn_(2)S_(4) *** on the experimental result,the photo-reactivity S-scheme mechanism of hydrogen evolution from water splitting with Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) is *** work provides an effective method for developing S-scheme heterojunction composites of transition metal sulfide with high hydrogen evolution performance.

关键词： ZnIn_(2)S_(4) nanosheets S-scheme heterojunction Sulfur vacancy Charge transfer and separation Photocatalytic H_(2)evolution

Retrospective Study Immune function status of postoperative patients with colon cancer for predicting liver metastasis

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 463-470页

作者： Le xiong fang-Chen Liu Department of Clinical Laboratory Xiangyang No.1 People’s HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Blood Transfusion Xiangyang No.1 People’s HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina

BACKGROUND Colon cancer(CC)has a high incidence *** resection is the main treatment method for CC;however,liver metastasis(LM)often occurs *** liver contains both innate and adaptive immune cells that monitor and remove abnormal cells and *** LM,tumor cells secrete cytokines and exosomes to adjust the immune microenvironment of the liver,thus forming an inhibitory immune microenvironment for colonization by circulating tumor *** indicates that the immune state of patients with CC plays a crucial role in the occurrence and progression of *** To observe and analyze the relationship between immune status and expression of tumor factors in patients with LM of CC,and to provide a scientific interven-tion method for promoting the patient *** A retrospective analysis was *** baseline data of 100 patients with CC and 100 patients with CC who suffered from postoperative LM and were admitted to our hospital from May 2021 to May 2023 were included in the non-occurrence and occurrence groups,*** immune status of the pa-tients and the expression of tumor factor-related indicators in the two groups were compared,and the predictive value of the indicators for postoperative LM in patients with CC was *** Compared with the non-occurrence group,the expression of serum carcinoem-bryonic antigen(CEA),CA19-9,CA242,CA72-4 and CA50 in patients in the occurrence group were significantly higher,while the expression of CD3+,CD4+,CD8+,natural killer(NK)and CD4+/CD25 in patients in the occurrence group were significantly lower(P0.05).Multivariate logistic regression model analysis revealed that the expressions of CEA,CA19-9,CA242,CA72-4,CA50,CD3+,CD4+,CD8+,NK,and CD4+/CD25 were associated with the LM in patients with *** expressions of serum CEA,CA19-9,CA242,CA72-4 and CA50,and low expressions of CD3+,CD4+,CD8+,

关键词： Colon cancer Liver metastases Immune status Tumor factors Predicted value

Unlocking T cell exhaustion:Insights and implications for CAR-T cell therapy

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3416-3431页

作者： Dian xiong Haijun Yu Zhi-jun Sun State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyFrontier Science Center for Immunology and MetabolismTaikang Center for Life and Medical ScienceWuhan UniversityWuhan 430079China Department of Radiation and Medical Oncology Hubei Province Cancer Clinical Study CenterHubei Key Laboratory of Tumor Biological BehaviorsZhongnan Hospital of Wuhan UniversityWuhan 430071China

Chimeric antigen receptor T(CAR-T)cell therapy as a form of adoptive cell therapy(ACT)has shown significant promise in cancer treatment,demonstrated by the FDA-approved CAR-T cell therapies targeting CD19 or B cell maturation antigen(BCMA)for hematological malignancies,albeit with moderate outcomes in solid ***,despite these advancements,the efficacy of CAR-T therapy is often compromised by T cell exhaustion,a phenomenon that impedes the persistence and effector function of CAR-T cells,leading to a relapse rate of up to 75%in patients treated with CD19 or CD22 CAR-T cells for hematological *** to overcome CAR-T exhaustion employ state-of-the-art genomic engineering tools and single-cell sequencing *** this review,we provide a comprehensive understanding of the latest mechanistic insights into T cell exhaustion and their implications for the current efforts to optimize CAR-T cell *** insights,combined with lessons learned from benchmarking CAR-T based products in recent clinical trials,aim to address the challenges posed by T cell exhaustion,potentially setting the stage for the development of tailored next-generation approaches to cancer treatment.

关键词： Cancer immunotherapy CAR-T therapy T cell exhaustion Tumor immune microenvironment Spatial immune contexture Single-cell technologies CAR-T engineering Combination therapy

Cobalt-nitrogen co-doped porous carbon sphere as highly efficient catalyst for liquid-phase cyclohexane oxidation with molecular oxygen and the active sites investigation

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 101-112页

作者： Lei Chen Yuan Sun Jinshan Chi Wei xiong Pingle Liu fang Hao College of Chemical Engineering National&Local United Engineering Research Centre for Chemical Process Simulation and IntensificationXiangtan UniversityXiangtan411105China

The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol(KA oil)is a challenging issue in the chemical *** present the industrial conversion of cyclohexane to cyclohexanone and cyclohexanol is normally controlled at less than 5%***,the development of highly active and stable catalysts for the aerobic oxidation of cyclohexane is necessary to overcome this low-efficiency ***,we have developed a cobalt-nitrogen co-doped porous sphere catalyst,Co-NC-x(x is the Zn/Co molar ratio,where x=0,0.5,1,2,and 4)by pyrolyzing resorcinol-formaldehyde resin *** achieved 88.28%cyclohexanone and cyclohexanol selectivity and a cyclohexane conversion of 8.88%under *** results showed that the introduction of zinc effectively alleviated the aggregation of Co nanoparticles and optimized the structural properties of the *** addition,Co0 and pyridinic-N are proposed to be the possible active species,and their proportion efficiently increased in the presence of Zn^(2+)*** this study,we developed a novel strategy to design highly active catalysts for cyclohexane oxidation.

关键词： KA oil production cyclohexane selective oxidation cobalt-nitrogen co-doped porous carbon spheres metal-organic framework

A review on reinforcement learning-based highway autonomous vehicle control

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Green Energy and Intelligent Transportation 2024年第4期3卷 72-90页

作者： Ali Irshayyid jun Chen Guojiang xiong Oakland University USA Guizhou UniversityChina

Autonomous driving is an active area of research in artificial intelligence and *** advances in deep reinforcement learning(DRL)show promise for training autonomous vehicles to handle complex real-world driving *** paper reviews recent advancement on the application of DRL to highway lane change,ramp merge,and platoon *** particular,similarities,differences,limitations,and best practices regarding the DRL formulations,DRL training algorithms,simulations,and metrics are reviewed and *** paper starts by reviewing different traffic scenarios that are discussed by the literature,followed by a thorough review on the DRL technology such as the state representation methods that capture interactive dynamics critical for safe and efficient merging and the reward formulations that manage key metrics like safety,efficiency,comfort,and *** from this review can guide future research toward realizing the potential of DRL for automated driving in complex traffic under uncertainty.

关键词： Autonomous vehicles Connected and automated vehicles Deep reinforcement learning Platoon

Effects of retained dry material on the impact,overflow and landing dynamics

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3629-3640页

作者： jun fang Yifei Cui Haiming Liu State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijingChina Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

During long-term operation,the performance of obstacles would be changed due to the material accumulating upslope the ***,the effects of retained material on impact,overflow and landing dynamics of granular flow have not yet been *** address this gap,physical flume tests and discrete element simulations are conducted considering a range of normalized deposition height h0/H from 0 to 1,where h0 and H represent the deposition height and obstacle height,*** analytical model is modified to evaluate the flow velocity and flow depth after interacting with the retained materials,which further serve to calculate the peak impact force on the ***,the computed impact forces successfully predict the experimental results when a≥25°.In addition,the results indicate that a higher h0/H leads to a lower dynamic impact force,a greater landing distance L,and a larger landing coefficient Cr,where Cr is the ratio of slope-parallel component of landing velocity to flow velocity just before *** to the existing overflow model,the measured landing distance L is underestimated by up to 30%,and therefore it is insufficient for obstacle design when there is retained ***,the recommended Cr in current design practice is found to be nonconservative for estimating the landing velocity of geophysical *** study provides insightful scientific basis for designing obstacles with deposition.

关键词： Granular flow Obstacle deposition Impact Overflow Landing

Two-way shape memory effect in a Ti-Zr-Nb-Ta high-temperature shape memory alloy

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Rare Metals 2024年第3期43卷 1257-1262页

作者： Cheng-Yang xiong Tuo Li jun Wang Yan Li School of Materials Science and Engineering Beihang UniversityBeijing100191China

The two-way shape memory effect in a Ti-18.5Zr-10Nb-3.5Ta high-temperature shape memory alloy was investigated.X-ray diffraction measurem ent shows that the alloy is composed of orthorhombicα"-martensite.ωphase is not found in Ti-18.5Zr-10Nb-3.5Ta alloy due to the suppressing effect of Ta ***α"-martensite laths are found in the transmission electron microscope observation;after the bending deformation,there appear a lot of *** alloy exhibits a shape memory strain of 3.8%aud a high reverse martensite transformation start temperature of 464 *** maximum two-way shape memory strain of 1.2%is obtained in the alloy with the prebending training strain of 10%.The mechanism can be ascribed to the effect of internal stress field caused by dislocations.

关键词： Ti-Zr Shape memory alloys Two-way shape memory effect

Identifying malicious traffic under concept drift based on intraclass consistency enhanced variational autoencoder

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Science China(Information Sciences) 2024年第8期67卷 238-252页

作者： Xiang LUO Chang LIU Gaopeng GOU Gang xiong Zhen LI Binxing fang Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences School of Computer Science and Technology Harbin Institute of Technology (Shenzhen)

Accurate identification of malicious traffic is crucial for implementing effective defense countermeasures and has led to extensive research efforts. However, the continuously evolving techniques employed by adversaries have introduced the issues of concept drift, which significantly affects the performance of existing methods. To tackle this challenge, some researchers have focused on improving the separability of malicious traffic representation and designing drift detectors to reduce the number of false ***, these methods often overlook the importance of enhancing the generalization and intraclass consistency in the representation. Additionally, the detectors are not sufficiently sensitive to the variations among different malicious traffic classes, which results in poor performance and limited robustness. In this paper, we propose intraclass consistency enhanced variational autoencoder with Class-Perception detector(ICE-CP) to identify malicious traffic under concept drift. It comprises two key modules during training:intraclass consistency enhanced(ICE) representation learning and Class-Perception(CP) detector construction. In the first module, we employ a variational autoencoder(VAE) in conjunction with Kullback-Leibler(KL)-divergence and cross-entropy loss to model the distribution of each input malicious traffic flow. This approach simultaneously enhances the generalization, interclass consistency, and intraclass differences in the learned representation. Consequently, we obtain a compact representation and a trained classifier for nondrifting malicious traffic. In the second module, we design the CP detector, which generates a centroid and threshold for each malicious traffic class separately based on the learned representation, depicting the boundaries between drifting and non-drifting malicious traffic. During testing, we utilize the trained classifier to predict malicious traffic classes for the testing samples. Then, we use the CP det

关键词： concept drift malicious traffic identification variational autoencoder intrusion detection cyberspace security