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Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： Rui Wang Zhiming Zhou Kaiwen li Tao Zhang ling Wang xin Xu Xiangke liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning

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Minocycline in the eradication of Helicobacter pylori infection: A systematic review and meta-analysis

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World Journal of Gastroenterology 2024年第17期30卷 2354-2368页

作者： Kai Zhou Cai-ling li Hua Zhang Bao-Jun Suo Yu-xin Zhang xin-Lu Ren Yu-xin Wang Chang-Min Mi ling-ling Ma li-Ya Zhou Xue-li Tian Zhi-Qiang Song Department of Gastroenterology Peking University Third HospitalBeijing 100191China

BACKGROUND Difficulty in obtaining tetracycline,increased adverse reactions,and relatively complicated medication methods have limited the clinical application of the classic bismuth quadruple ***,the search for new alternative drugs has become one of the research *** recent years,minocycline,as a semisynthetic tetracycline,has demonstrated good potential for eradicating Helicobacter pylori(***)infection,but the systematic evaluation of its role remains *** To explore the efficacy,safety,and compliance of minocycline in eradicating *** *** We comprehensively retrieved the electronic databases of PubMed,Embase,Web of Science,China National Knowledge Infrastructure,SinoMed,and Wanfang database as of October 30,2023,and finally included 22 research reports on *** eradication with minocycline-containing regimens as per the inclusion and exclusion *** eradication rates of *** were calculated using a fixed or a random effect model,and the heterogeneity and publication bias of the studies were *** The single-arm meta-analysis revealed that the minocycline-containing regimens achieved good overall *** eradication rates,reaching 82.3%[95%confidence interval(CI):79.7%-85.1%]in the intention-to-treat analysis and 90.0%(95%CI:87.7%-92.4%)in the per-protocol *** overall safety and compliance of the minocycline-containing regimens were good,demonstrating an overall incidence of adverse reactions of 36.5%(95%CI:31.5%-42.2%).Further by traditional meta-analysis,the results showed that the minocycline-containing regimens were not statistically different from other commonly used eradication regimens in eradication rate and incidence of adverse *** of the adverse reactions were mild to moderate and well-tolerated,and dizziness was relatively prominent in the minocycline-containing regimens(16%).CONCLUSION The minocycline-containing regimens demonstrated good efficacy,safety,and

关键词： Helicobacter pylori Minocycline Eradication Safety Resistance

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Impacts of high temperature,relative air humidity,and vapor pressure deficit on the seed set of contrasting maize genotypes during flowering

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Journal of Integrative Agriculture 2024年第9期23卷 2955-2969页

作者： xin Dong Baole li Zhenzhen Yan ling Guan Shoubing Huang Shujun li Zhiyun Qi ling Tang Honglin Tian Zhongjun Fu Hua Yang Chongqing Academy of Agricultural Sciences Chongqing 401329China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China

Heat stress is a major constraint to current and future maize production at the global *** and female reproductive organs both play major roles in increasing seed set under heat stress at flowering,but their relative contributions to seed set are *** this study,a 2-year field experiment including three sowing dates in each year and 20 inbred lines was *** set,kernel number per ear,and grain yield were all reduced by more than 80%in the third sowing dates compared to the first sowing *** viability,silk emergence ratio,and anthesis-silking interval were the key determinants of seed set under heat stress;and their correlation coefficients were 0.89^(***),0.65^(***),and-0.72^(***),*** pressure deficit(VPD)and relative air humidity(RH)both had significant correlations with pollen viability and the silk emergence *** RH can alleviate the impacts of heat on maize seed set by maintaining high pollen viability and a high silk emergence *** a warming climate from 2020 to 2050,VPD will decrease due to the increased *** on their pollen viability and silk emergence ratios,the 20 genotypes fell into four different *** group with high pollen viability and a high silk emergence ratio performed better under heat stress,and their performance can be further improved by combining the improved flowering pattern traits.

关键词： maize pollen viability silk emergence heat stress relative humidity

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High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： li-Dong Qin xin-Yu Wang Qaiser Mahmood Zhi-xin Yu Yi-Zhou Wang Song Zou Tong-ling liang Wen-Hua Sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

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Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第02期34卷 376-388页

作者： ling Zhang Yinglong li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

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Mechanical characteristics and reservoir stimulation mechanisms of the Gulong shale oil reservoirs, the northern Songliao Basin

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Petroleum Science 2024年第3期21卷 2023-2036页

作者： Si-Wei Meng Jia-Ping Tao Tian-Jiao li Dong-Xu li Su-ling Wang liu Yang xin liu li-Hao liang He liu PetroChina Research Institute of Petroleum Exploration Development Beijing100083China National Key Laboratory of Continental Shale Oil Daqing 163002HeilongjiangChina Dalian University of Technology Dalian116024LiaoningChina PetroChina Daqing Oilfield Co.Ltd. Daqing163002HeilongjiangChina Northeast Petroleum University Daqing163002HeilongjiangChina China University of Mining and Technology(Beijing) Beijing100083China

Shale oil of the Qingshankou Formation of the Gulong Sag,the northern Songliao Basin,represents the first attempt at large-scale development of pure-shale-type shale oil in *** integrating the multiscale refined reservoir characterization with macro-micro-scale mechanical testing,it is clarified that the Gulong shale is characterized by high clay mineral content,high rock plasticity,highly-developed bedding,and prominent mechanical anisotropy.A three-dimensional(3D)fracture propagation model of hydraulic fracturing was built for the Gulong shale,which fully captures the hydraulic fracture distribution pattern affected by the high bedding density,in-situ stress,and fracturing treatment *** research showed that due to influences of bedding,hydraulic fracturing in the Gulong shale forms a complex fracture morphology featuring the main fracture with multiple perpendicular branches that have different lengths(like the outdoor directional TV antenna);however,the vertical propagation of fractures is inhibited,and the fracture height is commonly less than 10 *** limited stimulated reservoir volume(SRV)is the main problem facing the fracturing stimulation of the Gulong shale *** density has vital effects on fracture morphology,so case-specific fracturing designs shall be developed for shale intervals with different bedding development *** reservoirs with welldeveloped bedding,it is suggested to properly increase the perforation cluster spacing and raise the volume and proportions of viscous fluids of the pad,so as to effectively promote vertical fracture propagation and improve reservoir stimulation *** study integrates multi-scale fine reservoir characterization and macro-micro-scale mechanical testing,as well as the construction and numerical simulation of hydraulic fracturing models for high-density layered shale reservoirs,providing a new approach and methodological framework for the fracturing research of high-density layer

关键词： Shale oil Hydraulic fracturing High bedding density Fracture propagation model

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Evolution and function of residual solvent in polymer-li_2B_(12)H_(12) composite solid electrolyte

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Rare Metals 2024年第8期43卷 3748-3757页

作者： Xiang-Yang Ye Ke-Pan Bao Sai-Nan Luo xin li Tai-Qiang Chen Shui-xin Xia Tao Yuan Yue-Peng Pang Shi-You Zheng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Department of Materials Science and Engineering National University of SingaporeSingapore 119077Singapore

Composite solid electrolytes(CSEs) containing polymer matrices and inorganic fillers hold promise for the next generation of solid-state ***,the role of residual solvents in CSEs remains *** study investigated the evolution and function of the residual solvent in a polymer-li_2B_(12)H_(12) CSE.A partial reaction occurred between li_2B_(12)H_(12) and solvent N,N-dimethylformamide(DMF),which produced dimethylaminomethanol(DMAM) in the *** functional theory calculations have revealed that DMA M forms stronger hydrogen bonds with polyvinylidene fluoride chains than DMF,which can have a plasticizing effect on the polymer matrix,leading to lower crystallinity and quicker segment ***,this CSE exhibited improved li-ion conducting properties,enabling the stable cycling of li‖liFePO_(4) solid-state *** study provided insights into the role of residual solvents in CSEs.

关键词： Composite solid electrolyte Residual solvent lithium borohydride Plasticizing effect

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D-band center coordination modulated enzyme-like activity in Fe-Cu dual-metal single-atom nanozymes

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Nano Research 2024年第7期17卷 5872-5883页

作者： ling liu Shaofang Zhang Guo li Yadong Zhe Jiamin liu xinxu Zhang Jiahao Wei xin Sun Yonghui li Xiao-Dong Zhang Tianjin Key Laboratory of Brain Science and Neural Engineering Academy of Medical Engineering and Translational MedicineTianjin UniversityTianjin 300072China Department of Physics and Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology School of SciencesTianjin UniversityTianjin 300350China

After explorations in a diversity of single-atom nanozymes(SAzymes),developing dual-centered SAzymes becomes a promising approach for superior catalytic *** confusing mechanisms including atomic coordination,spatial configuration,and metal–metal atom interaction hinder the development and design of ***,a dual-centered Fe-Cu-N_(x)SAzyme exhibits excellent peroxidase(POD)-and catalase(CAT)-like activities with d-band center(ε_(d))coordination of Fe and Cu in multiple reaction stages,which plays a critical role in the adsorption of H_(2)O_(2)molecule and H_(2)O and O_(2)***,the dband center coordination,which can be represented byε_(d)(Fe)–ε_(d)(Cu)shifts,leads to the competition between one-side and bilateral adsorption,which determines the favorable reaction path with lower energy *** on experimental statistics,simulated formation energies,and reaction barriers,3 configurations,Fe-Cu-N6-I,Fe-Cu-N_(8)-II,and Fe-Cu-N_(8)-III,are modeled and ***,configuration-dependent catalytic selectivity and the competition between one-side and bilateral adsorption can be unveiled by d-band center coordination paradigm *** simulations suggest that the unsymmetrical charge distribution over the three Fe-Cu configurations could tune the adsorption strength compared with the counterparts FeN_(4)and CuN_(4).The present work provides a potential route for optimizing enzyme-like catalysis by designing the dual-or even triple-metal SAzymes,which demonstrates the large space to modulate the metal atomic configuration and interaction.

关键词： single-atom catalysis Fe-Cu dual-metal d-band center coordination enzyme mimicking competitive adsorption mechanisms

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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration

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Petroleum Science 2024年第2期21卷 806-822页

作者： Jin-Min Song xin Jin Zhong Luo Shu-Gen liu Shao-Bo liu xing-Zhi Ma Zhi-Wu li Xue-Song Lu ling-li Zhao Ke-Ran li Jia-xin Ren li-Zhou Tian Hao-Shuang Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina PetroChina Research Institute of Petroleum Exploration and Development Beijing100083China Xihua University Chengdu610039SichuanChina

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain late

关键词： Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications

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Lactiplantibacillus plantarum AR113 alleviates microbiota dysbiosis of tongue coating and cerebral ischemia/reperfusion injury in rat

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Food Science and Human Wellness 2024年第4期13卷 2132-2140页

作者： Zhiqiang Xiong Gang liu ling Fang Xiuming li Yongjun Xia Guangqiang Wang xin Song lianzhong Ai Shanghai Engineering Research Center of Food Microbiology School of Health Science and EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China Department of Rehabilitation Huashan HospitalFudan UniversityShanghai 200040China Department of Rehabilitation Medicine Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

Stroke is one of the leading causes of death and disability ***,information on stroke-related tongue coating microbiome(TCM)is limited,and whether TCM modulation could benefit for stroke prevention and rehabilitation is ***,TCM from stroke patients(SP)was characterized using molecular *** occurrence of stroke resulted in TCM dysbiosis with significantly reduced species richness and *** abundance of Prevotella,Leptotrichia,Actinomyces,Alloprevotella,Haemophilus,and TM7_[G-1]were greatly reduced,but common infection Streptococcus and Pseudomonas were remarkably ***,an antioxidative probiotic Lactiplantibacillus plantarum AR113 was used for TCM intervention in stroke rats with cerebral ischemia/reperfusion(I/R).AR113 partly restored I/R induced change of TCM and gut microbiota with significantly improved neurological deficit,relieved histopathologic change,increased activities of antioxidant enzymes,and decreased contents of oxidative stress ***,the gene expression of antioxidant-related proteins and apoptosis-related factors heme oxygenase-1(HO-1),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),nuclear factor erythroid 2-related factor 2(Nrf2),NAD(P)H:quinone oxidoreductase-1(NQO-1),and Bcl-2 was significantly increased,but cytochrome C,cleaved caspase-3,and Bax were markedly decreased in the brain by AR113 *** results suggested that AR113 could ameliorate cerebral I/R injury through antioxidation and anti-apoptosis pathways,and AR113 intervention of TCM may have the application potential for stroke prevention and control.

关键词： Stroke Cerebral ischemia/reperfusion Tongue coating Lactiplantibacillus plantarum AR113 Probiotic intervention

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