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Extensive numerical simulations on competitive growth between the Edwards–Wilkinson and Kardar–Parisi–Zhang universality classes

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Chinese Physics B 2024年第6期33卷 298-307页

作者：余成志刘潇唐军夏辉 School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Extensive numerical simulations and scaling analysis are performed to investigate competitive growth between the linear and nonlinear stochastic dynamic growth systems, which belong to the Edwards–Wilkinson(EW) and Kardar–Parisi–Zhang(KPZ) universality classes, respectively. The linear growth systems include the EW equation and the model of random deposition with surface relaxation(RDSR), the nonlinear growth systems involve the KPZ equation and typical discrete models including ballistic deposition(BD), etching, and restricted solid on solid(RSOS). The scaling exponents are obtained in both the(1 + 1)-and(2 + 1)-dimensional competitive growth with the nonlinear growth probability p and the linear proportion 1-p. Our results show that, when p changes from 0 to 1, there exist non-trivial crossover effects from EW to KPZ universality classes based on different competitive growth rules. Furthermore, the growth rate and the porosity are also estimated within various linear and nonlinear growths of cooperation and competition.

关键词： competitive growth scaling behavior discrete growth model Kardar–Parisi–Zhang universality class

Failure mechanism and simulation for long run-out of the catastrophic rock landslide in the Shanyang Vanadium Mine,China

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Journal of Mountain Science 2024年第9期21卷 2905-2917页

作者： liu Yinpeng Mumtaz HAIDER David-darnor LAWRENCE LI Tonglu SHEN Wei LI Ping College of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Observation and Research Station of Water Cycle and Geological Environment for the Chinese Loess Plateau Ministry of EducationZhengning 745399China

On 12th August 2015,a massive rapid long run-out rock landslide occurred in the Shanyang Vanadium Mine in Shaanxi Province,China,which claimed the lives of 65 *** heavy rainfalls,earthquakes,and mining blasts were recorded before the ***,the failure mechanism and the cause of the long run-out movement are always in *** this paper,we conducted a detailed field investigation,laboratory tests,block theory analysis,and numerical simulation to investigate the failure and long run-out mechanisms of the *** field investigation results show that the source material of the rock landslide is a huge dolomite wedge block bedding on siliceous shale *** compression tests indicate that the uniaxial compression strength of the intact dolomite is 130-140MPa and the dolomite shows a brittle failure *** to the progressive downward erosion of the gully,the dolomite rock bridge at the slope toe became *** the compression stress in the dolomite bridge increased to surpass its strength,the brittle failure of the bridge *** huge potential energy was released following the disintegration of the landslide,which led to the high acceleration of this rock *** 3D discrete element simulation results suggest that the low intergranular friction contributes to the long run-out movement of this rock landslide.

关键词： Rock landslide Gully erosion Long run-out Wedge block Discrete element method

A CombustionModel for Explosive Charge Affected by a Bottom Gap in the Launch Environment

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1207-1236页

作者： ShiboWu Weidong Chen Jingxin Ma Lan liu Shengzhuo Lu Honglin Meng Xiquan Song College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin150001China General Department of Experimental Technology Beijing Institute of Structure and Environment EngineeringBeijing100076China Department of Economics Kunlun Energy Holding Company LimitedBeijing100101China

Launch safety of explosive charges has become an urgent problem to be solved by all countries in the world aslaunch situation of ammunition becomes ***, the existing numericalmodels have differentdefects. This paper formulates an efficient computational model of the combustion of an explosive charge affectedby a bottom gap in the launch environment in the context of the material point method. The current temperatureis computed accurately from the heat balance equation, and different physical states of the explosive charges areconsidered through various equations of state. Microcracks in the explosive charges are described with respectto the viscoelastic statistical crackmechanics (Visco–SCRAM) model. Themethod for calculating the temperatureat the bottomof the explosive charge with respect to the bottomgap is described. Based on this combustionmodel,the temperature history of a Composition B (COMB) explosive charge in the presence of a bottom gap is obtainedduring the launch process of a 155-mm artillery. The simulation results show that the bottom gap thickness shouldbe no greater than 0.039 cm to ensure the safety of the COM B explosive charge in the launch environment. Thisconclusion is consistent with previous results and verifies the correctness of the proposed model. Ultimately, thispaper derives amathematical expression for themaximumtemperature of the COMB explosive chargewith respectto the bottomgap thickness (over the range of 0.00–0.039 cm), and establishes a quantitative evaluationmethod forthe launch safety of explosive *** research results provide some guidance for the assessment and detectionof explosive charge safety in complex launch environments.

关键词： Combustion model explosive charge safety launch environment bottom gap temperature

Establishing Modular Cell-Free Expression System for the Biosynthesis of Bicyclomycin from a Chemically Synthesized Cyclodipeptide

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Chinese Journal of Chemistry 2024年第4期42卷 384-390页

作者： Yi-Pei liu Yu-Heng Zhao Wen-Qi Zhang Lian Wu Linjuan Huang Gong-Li Tang Jun-Bin He Shaanxi Natural Carbohydrate Resource Engineering Research Center College of Food Science and TechnologyNorthwest UniversityXi'anShaanxi710069 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences(CAS)CASShanghai200032 China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of CAS1 Sub-lane XiangshanHangzhouZhejiang310024 China

Cell-free expression systems have emerged as a versatile and powerful platform for metabolic engineering,biosynthesis and synthetic biology ***,successful examples of the synthesis of complex natural products using this system are still ***,a structurally unique and complex diketopiperazine alkaloid,is a clinically promising antibiotic that selectively inhibits the transcription termination factor ***,we established a modular cell-free expression system with cascade catalysis for the biosynthesis of bicyclomycin from a chemically synthesized *** six cell-free expressed biosynthetic enzymes,including five iron-andα-ketoglutarate-dependent dioxygenases and one cytochrome P450 monooxygenase,were active in converting their substrates to the corresponding *** co-expressed enzymes in the cell-free module were able to complete the related partial *** vitro biosynthesis of bicyclomycin was also achieved by reconstituting the entire biosynthetic pathways(i.e.,six enzymes)using the modular cell-free expression *** study demonstrates that the modular cell-free expression system can be used as a robust and promising platformforthe biosynthesis of complex antibiotics.

关键词： Natural products Bicyclomycin Biosynthesis Iron-andα-ketoglutarate-dependent dioxygenases Cytochrome P450 monooxygenase Cell-freeprotein synthesis Enzyme catalysis

Structure-based design and optimization lead to the identification of novel dihydrothiopyrano[3,2-d]pyrimidine derivatives as potent HIV-1 inhibitors against drug-resistant variants

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1257-1282页

作者： Zhao Wang Heng Zhang Zhen Gao Zihao Sang Erik De Clercq Christophe Pannecouque Dongwei Kang Peng Zhan Xinyong liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China Rega Institute for Medical Research Laboratory of Virology and ChemotherapyK.U.LeuvenLeuven B-3000Belgium China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province Jinan 250012China Suzhou Research Institute Shandong UniversitySuzhou 215123China

With our continuous endeavors in seeking potent anti-HIV-1 agents,we reported here the discovery,biological characterization,and druggability evaluation of a class of nonnucleoside reverse transcriptase *** fully explore the chemical space of the NNRTI-binding pocket,novel series of dihydrothiopyrano[3,2-d]pyrimidines were developed by employing the structure-based design *** of the derivatives were endowed with prominent antiviral activities against HIV-1 wild-type and resistant strains at nanomolar *** them,compound 23h featuring the aminopiperidine moiety was identified as the most potent inhibitor,with EC50values ranging from 3.43 to 21.4 nmol/***,for the challenging double-mutants F227L+V106A and K103N+Y181C,23h exhibited 2.3-to 14.5-fold more potent activity than the first-line drugs efavirenz and ***,the resistance profiles of 23h achieved remarkable improvement compared to efavirenz and *** binding target of 23h was further confirmed to be HIV-1 reverse *** modeling studies were also performed to elucidate the biological evaluation results and give guidance for the optimization ***,no apparent inhibition of the major CYP450 enzymes and hERG channel was observed for *** importantly,23h was characterized by good pharmacokinetic properties and excellent safety in ***,23h holds great promise as a potential candidate for its effective antiviral efficacy and favorable drug-like profiles.

关键词： HIV-1 Reverse transcriptase Dihydrothiopyrano[3,2-d]pyrimidine Antiviral agent

The role of vitamin E in polyunsaturated fatty acid synthesis and alleviating endoplasmic reticulum stress in sub-adult grass carp(Ctenopharyngodon idella)

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Animal Nutrition 2024年第1期16卷 275-287页

作者： Ke Yao Lin Feng Wei-Dan Jiang Yang liu Lu Zhang Hai-Feng Mi Xiao-Qiu Zhou Pei Wu Animal Nutrition Institute Sichuan Agricultural University Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural University Key Laboratory of Animal Disease-Resistance Nutrition Ministry of Education Ministry of Agriculture and Rural Affairs Key Laboratory of Sichuan Province Tongwei Co. Ltd. Healthy Aquaculture Key Laboratory of Sichuan Province

Vitamin E(VE) is an essential lipid-soluble vitamin that improves the fish flesh quality. However, the underlying molecular mechanisms remain unclear. This study aimed to investigate the effects of VE on growth performance and flesh quality in sub-adult grass carp(Ctenopharyngodon idella). A total of 450fish(713.53 ± 1.50 g) were randomly divided into six treatment groups(three replicates per treatment)and fed for nine weeks with different experimental diets(dietary lipid 47.8 g/kg) that contained different levels of VE(5.44, 52.07, 96.85, 141.71, 185.66, and 230.12 mg/kg diet, supplemented as dl-a-tocopherol acetate). Notably, the treatment groups that were fed with dietary VE ranging from 52.07 to230.12 mg/kg diet showed improvement in the percent weight gain, special growth rate, and feed efficiency of grass carp. Moreover, the treatment groups supplemented with dietary VE level of 141.71,185.66, and 230.12 mg/kg diet showed enhancement in crude protein, lipid, and a-tocopherol contents in the muscle, and the dietary levels of VE ranging from 52.07 to 141.71 mg/kg diet improved muscle pH24h and shear force but reduced muscle cooking loss in grass carp. Furthermore, appropriate levels of VE(52.07 to 96.85 mg/kg diet) increased the muscle polyunsaturated fatty acid content in grass carp. Dietary VE also increased the mRNA levels of fatty acid synthesis-related genes, including fas, scd-1, fad,elovl, srebp1, pparγ, and lxra, and up-regulated the expression of SREBP-1 protein. However, dietary VE decreased the expression of fatty acid decomposition-related genes, including hsl, cpt1, acox1, and ppara,and endoplasmic reticulum stress-related genes, including perk, ire1, atf6, eif2a, atf4, xbp1, chop, and grp78, and down-regulated the expression of p-PERK, p-IRE1, ATF6, and GRP78 proteins. In conclusion,dietary VE increased muscle fatty acid synthesis, which may be partly associated with the alleviation of endoplasmic reticulum stress, and ultimately improves fish fles

关键词： Vitamin E Flesh quality Muscle polyunsaturated fatty acid level Endoplasmic reticulum stress Growth performance Grass carp

Evaluating the use of three-dimensional reconstruction visualization technology for precise laparoscopic resection in gastroesophageal junction cancer

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1311-1319页

作者： Dan Guo Xiao-Yan Zhu Shuai Han Yu-Shu liu Da-Peng Cui Department of Hepatobiliary Surgery The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Department of Anesthesiology The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Laparoscopic gastrectomy for esophagogastric junction(EGJ)carcinoma enables the removal of the carcinoma at the junction between the stomach and esophagus while preserving the gastric function,thereby providing patients with better treatment outcomes and quality of ***,this surgical technique also presents some challenges and ***,three-dimensional reconstruction visualization technology(3D RVT)has been introduced into the procedure,providing doctors with more comprehensive and intuitive anatomical information that helps with surgical planning,navigation,and outcome *** To discuss the application and advantages of 3D RVT in precise laparoscopic resection of EGJ *** Data were obtained from the electronic or paper-based medical records at The First Affiliated Hospital of Hebei North University from January 2020 to June 2022.A total of 120 patients diagnosed with EGJ carcinoma were included in the *** these,68 underwent laparoscopic resection after computed tomography(CT)-enhanced scanning and were categorized into the 2D group,whereas 52 underwent laparoscopic resection after CT-enhanced scanning and 3D RVT and were categorized into the 3D *** study had two outcome measures:the deviation between tumor-related factors(such as maximum tumor diameter and infiltration length)in 3D RVT and clinical reality,and surgical outcome indicators(such as operative time,intraoperative blood loss,number of lymph node dissections,R0 resection rate,postoperative hospital stay,postoperative gas discharge time,drainage tube removal time,and related complications)between the 2D and 3D *** Among patients included in the 3D group,27 had a maximum tumor diameter of less than 3 cm,whereas 25 had a diameter of 3 cm or *** actual surgical observations,24 had a diameter of less than 3 cm,whereas 28 had a diameter of 3 cm or *** findings were consistent between the two methods(χ^(2)=0.346,P=0.556),w

关键词： Gastroesophageal junction cancer Endoscopy Tumor resection Three-dimensional reconstruction visualization Two-dimensional imaging computed tomography

Promoting interactions between cognitive science and large language models

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The Innovation 2024年第2期5卷 9-10页

作者： Youzhi Qu Penghui Du Wenxin Che Chen Wei Chi Zhang Wanli Ouyang Yatao Bian Feiyang Xu Bin Hu Kai Du Haiyan Wu Jia liu Quanying liu Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055China Shanghai AI Laboratory Shanghai 200232China Tencent AI Lab Shenzhen 518057China iFLYTEK AI Research Hefei 230088China School of Medical Technology Beijing Institute of TechnologyBeijing 100081China Institute for Artificial Intelligence Peking UniversityBeijing 100871China Centre for Cognitive and Brain Sciences and Department of Psychology University of MacaoMacao 999078China Department of Psychology Tsinghua UniversityBeijing 100084China

Large language models(LLMs)have made unprecedented progress,demonstrating human-like language proficiency and an extraordinary ability to encode complex *** emergence of high-level cognitive capabilities in LLMs,such as in-context learning and complex reasoning,suggests a path toward the realization of artificial general intelligence(AGI).However,we lack scientific theories and tools to assess and interpret such an emergence of the advanced intelligence of *** intelligence(AI)has been extensively applied in various areas of fundamental science to accelerate scientific research.

关键词： cognitive such language

A review of the catalytic preparation of mesophase pitch

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新型炭材料（中英文） 2024年第4期39卷 583-610页

作者： MA Zi-hui YANG Tao SONG Yan CHEN Wen-sheng DUAN Chun-feng SONG Huai-he TIAN Xiao-dong GONG Xiang-jie liu Zheng-yang liu Zhan-jun CAS Key Laboratory for Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Because of its high purity and excellent orientation, mesophase pitch is a superior precursor for high-performance car-bon materials. However, the preparation of top-notch mesophase pitch faces challenges. Catalytic polycondensation at low temperat-ures is more favorable for synthesizing mesophase pitch, because it circumvents the high-temperature free radical reaction of other thermal polycondensation approaches. The reaction is gentle and can be easily controlled. It has the potential to significantly im-prove the yield of mesophase pitch and easily introduce naphthenic characteristics into the molecules, catalytic polycondensation is therefore a preferred method of synthesizing highly spinnable mesophase pitch. This review provides a synopsis of the selective pre-treatment of the raw materials to prepare different mesophase pitches, and explains the reaction mechanism and associated research advances for different catalytic systems in recent years. Finally, how to manufacture high-quality mesophase pitch by using a cata-lyst-promoter system is summarized and proposed, which may provide a theoretical basis for the future design of high-quality pitch molecules.

关键词： Mesophase pitch Catalytic polycondensation Lewis-acid Brønsted acid Catalyst-promoter system