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Fight or flee,a vital choice for Clostridioides difficile

mLife 2024年第1期3卷 14-20页

作者： Ji Zeng Sshuying Fang Jinquan guo Min dong guo-bao Tian Liang Tao School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhouChina Department of Brest Surgery Panyu Central Hospital.GuangzhouChina Department of Microbiology Harvard Medical SchoolBostonMassachusettsUSA Department of Urology Boston Children's HospitalHarvard Medical SchoolBostonMassachusettsUSA Department of Microbiology Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina Advanced Medical Technology Center The First Affiliated HospitalZhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina Key Laboratory of Tropical Diseases Control(Sun Yat-sen University) Ministry of EducationGuangzhouChina School of Medicine Xizang Minzu UniversityXianyangChina Center for Infectious Disease Research Westlake Laboratory of Life Sciences and BiomedicineWestlake UniversityHangzhouChina Research Center for Industries of the Future School of Life SciencesWestlake UniversityHangzhouChina

Clostridioides difficile is a leading cause of healthcare-associated infections,causing billions of economic losses every year.Its symptoms range from mild diarrhea to life-threatening damage to the colon.Transmission and recurrence of c.difficile infection(CDl)are mediated by the metabolically dormant spores,while the virulence of C.difficile is mainly due to the two large clostridial toxins,TcdA and TcdB.Producing toxins or forming spores are two different strategies for C.difficile to cope with harsh environmental conditions.It is of great significance to understand the molecular mechanisms for C.difficile to skew to either of the cellular processes.Here,we summarize the current understanding of the regulation and connections between toxin production and sporulation in C.difficile and further discuss the potential solutions for yet-to-be-answered questions.

关键词： C.difficile sporulation TcdA TcdB toxin production

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Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： dong Pan Qing-tao guo Kai-lun Zhang Fu-zhi Yu Yu-ying Li Yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting billets.Different from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification defects.In this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring methods.Following a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 Hz.The higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of billet.The experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element segregation.The SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-Yu Li Li-Le Liu guo-Xiang dong Xiao-bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

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Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang guo Wenqing YANG Yuanbo dong dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their wings.In order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)analysis.However,there exists controversy among researchers regarding the relationship between frequency and aerodynamic performance.Recognizing that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant frequency.In this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM analyses.The performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic performance.Notably,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum efficiency.Thus,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible wings.Furthermore,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure changes.This paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

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A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

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Acta Mechanica Solida Sinica 2024年第1期37卷 90-98页

作者： Zhaochen dong Yichao Zhu Xu guo State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116023China

Most existing treatments for origami-folding simulations have focused on regular-shaped configurations.This article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities nowadays.To better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between planes.Based on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five candidates.When the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami configuration.When the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

关键词： Irregular-shaped origami Complex deformation Computer-aided origami design General simulation

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New clinical trial design in precision medicine:discovery,development and direction

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1293-1321页

作者： Xiao-Peng Duan bao-dong Qin Xiao-dong Jiao Ke Liu Zhan Wang Yuan-Sheng Zang Department of Medical Oncology Changzheng HospitalNaval Medical UniversityShanghaiChina

In the era of precision medicine,it has been increasingly recognized that individuals with a certain disease are complex and different from each other.Due to the underestimation of the significant heterogeneity across participants in traditional"one-sizefits-all"trials,patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket,umbrella,and platform trial designs under the master protocol framework.In recent years,the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous opportunities.Despite the rapid increase in the number of basket,umbrella,and platform trials,the current clinical and research understanding of these new trial designs,as compared with traditional trial designs,remains limited.The majority of the research focuses on methodologies,and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial designs.Therefore,we provide this comprehensive review of the discovery and development of basket,umbrella,and platform trials and their underlying logic from the perspective of precision medicine.Meanwhile,we discuss future directions on the potential development of these new clinical design in view of the"Precision Pro","Dynamic Precision",and"Intelligent Precision".This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic,which be essential to accelerate the progression of precision medicine.

关键词： clinical approval successive

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Recent Advances in Pd-Catalyzed Reactions Involving the “On-Water” Mechanism

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Chinese Journal of Chemistry 2024年第5期42卷 533-542页

作者： dong Wei guo-Qiang Lin State Key Laboratory of Systems Medicine for Cancer Shanghai Cancer InstituteShanghai Key Laboratory of Systems Regulation and Clinical Translation for CancerRen Ji HospitalShanghai Jiao Tong University School of MedicineShanghai200127 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032 China

As the chemical industry grapples with the need for more eco-friendly practices,the use of water as a reaction medium is gaining attraction in organic transformations.This mini-review delves into Pd-catalyzed reactions that utilize the "on-water" mechanism,spanning from 2019 to late 2023.These reactions are neatly categorized into several types: (A) Catalytic C—H activations,(B) Mizoroki- Heck-type reactions,(C) Suzuki-Miyaura reactions,and (D) Cyclization reactions.By showcasing the potential of water as a sustainable reaction medium for organic transformations,these reactions leave no doubt about the importance of embracing eco-friendly practices in the chemical industry.Key Scientists In 1980,a seminal work by Breslow et al.showed an acceleration of reaction rate in the Diels-Alder reaction.Sharpless and co-workers noted a significant increase in the rate of the [2σ+2σ+2π] cycloaddition of quadricyclane and dimethyl azodicarboxylate (DMAD) when the reaction was conducted in water,as opposed to when it was carried out in organic solvents.The term "on-water" was then coined to describe this phenomenon.This strategy was further expanded to transition-metal catalyzed transformations by Ackermann in 2011.Later,Varma and Leazer disclosed a Pd-catalyzed Mizoroki-Heck type arylation of alkenes with diaryliodonium salts “on-water”.The enantioselective version of "on-water" process was not realized until 2014 by the Zhou group.Later on,the Schaub group described a Pd-catalyzed Suzuki–Miyaura coupling reaction of electron-poor aryl chlorides with water,using only 50 ppm of catalyst loading.Very recently,Liu and Lin extended the "on-water" strategy to Pd-catalyzed double Mizoroki-Heck reactions.This mini-review has focused on Pd-catalyzed reactions involving the “on-water” mechanism.

关键词： Pd-catalyzed “On-water” Green chemistry Aqueous reactions Mechanism Methodology and reactions Mizoroki-Heck reaction Cross-coupling

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Impact of Alcian blue and periodic acid Schiff expression on the prognosis of gastric signet ring cell carcinoma

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 687-698页

作者： Juan Lin Zhu-Feng Chen guo-dong guo Xin Chen Shengli Clinical Medical College Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Pathology Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina Department of Internal Medicine Fujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

BACKGROUND The Alcian blue(AB)and periodic acid Schiff(PAS)stains are representative mucus markers in gastric signet ring cell carcinoma(SRCC).They are low-cost special staining methods used to detect acidic mucus and neutral mucus,respectively.However,the clinical importance of the special combined AB and PAS stain is unclear.AIM To investigate AB expression,PAS expression and the AB-to-PAS(A/P)ratio in gastric SRCC patients and to assess patient prognosis.METHODS Paraffin-embedded sections from 83 patients with gastric SRCC were stained with AB and PAS,and signet ring cell positivity was assessed quantitatively.Immuno-histochemical staining for Ki67,protein 53(P53)and human epidermal growth factor receptor 2(HER2)was performed simultaneously.The cancer-specific survival(CSS)rate was estimated via Kaplan-Meier analysis.Cox proportional hazards models were used for univariate and multivariate survival analyses.RESULTS Kaplan-Meier survival analysis revealed that the 3-year CSS rate was significantly greater in the high-PAS-expression subgroup than in the low-PAS-expression subgroup(P0.5 group(P=0.042).Univariate Cox regression analysis revealed that the factors affecting prognosis included tumor diameter,lymph node metastasis,vessel carcinoma embolus,tumor stage,the A/P ratio and the expression of Ki67,P53 and the PAS.Cox multivariate regression analysis confirmed that low PAS expression[hazard ratio(HR)=3.809,95%confidence interval(CI):1.563-9.283,P=0.003]and large tumor diameter(HR=2.761,95%CI:1.086-7.020,P=0.033)were independent risk factors for poor prognosis.CONCLUSION A/P>0.5 is potentially a risk factor for prognosis,and low PAS expression is an independent risk factor in the prognosis of gastric SRCC.PAS expression and the A/P ratio could help in predicting the clinical prognosis of patients with SRCC.

关键词： Alcian blue Periodic acid-Schiff Prognosis Gastric Signet ring cell carcinoma

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Density functional theory study of B- and Si-doped carbons and their adsorption interactions with sulfur compounds

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Carbon Energy 2024年第2期6卷 195-208页

作者： Peng guo Hong Zhang Shuliang dong Libao An College of Mechanical Engineering North China University of Science and TechnologyTangshanHebeiChina College of Life Sciences North China University of Science and TechnologyTangshanHebeiChina

Understanding the adsorption interactions between carbon materials and sulfur compounds has far-reaching impacts,in addition to their well-known important role in energy storage and conversion,such as lithium-ion batteries.In this paper,properties of intrinsic B or Si single-atom doped,and B-Si codoped graphene(GR)and graphdiyne(GDY)were investigated by using density functional theory-based calculations,in which the optimal doping configurations were explored for potential applications in adsorbing sulfur compounds.Results showed that both B or Si single-atom doping and B-Si codoping could substantially enhance the electron transport properties of GR and GDY,improving their surface activity.Notably,B and Si atoms displayed synergistic effects for the codoped configurations,where B-Si codoped GR/GDY exhibited much better performance in the adsorption of sulfurcontaining chemicals than single-atom doped systems.In addition,results demonstrated that,after B-Si codoping,the adsorption energy and charge transfer amounts of GDY with sulfur compounds were much larger than those of GR,indicating that B-Si codoped GDY might be a favorable material for more effectively interacting with sulfur reagents.

关键词： adsorption density functional theory doping graphdiyne graphene sulfur compounds

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Potential evaluation and implementation strategy for pocket park construction in high-density urban areas: A case study in Dalian, China

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Frontiers of Architectural Research 2024年第2期13卷 319-334页

作者： Jing dong Ruonan guo Fei guo Jun Cai School of Architecture and Fine Art Dalian University of TechnologyDalian 116024China

As an important element of urban renewal in highly urbanized areas, pocket parks with small size, flexible layout and daily accessibility are becoming a major component of green infrastructure and the mainstay of outdoor recreation space expansion in high-density urban centers. Nevertheless, the absence of a comprehensive framework for evaluating the potential of pocket park construction (PPC), one that integrates diverse influencing factors on a macro scale, has resulted in the random installation of such spaces, often failing to optimize the utilization of urban land. Addressing this critical lacuna, we propose an approach to evaluate PPC potential from a city-scale perspective, which is used to support the determination of which land units should be prioritized for PPC. A complete and feasible workflow was also established to identify potential land units, construct an index system for PPC combining demand and supply levels, quantitatively calculate indices based on remote sensing (RS) and geographic information system (GIS), accurately evaluate PPC potential using an entropy-weighted TOPSIS model, and develop targeted renewal strategies. A case study in Dalian, China, demonstrated the applicability and implications of the workflow. The results showed that it is flexible and easy to adapt to different local contexts, allowing evaluators to introduce parameters considering the availability of local data, and will help decision makers to build pocket parks in the most effective plots, providing a strong reference for high-quality development in other high-density urban centers facing the contradiction between ecological construction and land scarcity.

关键词： Pocket park Potential evaluation Urban renewal High-density urban areas

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