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Intracellular redox potential-driven live-cell synthesis of CdSe quantum dots in Staphylococcus aureus

Science China Chemistry 2024年第3期67卷 990-999页

作者： Cai-Qin Wu An-An Liu xu Li jia-wei Tu Juan Kong Ling-Ling Yang jian-Hong jia Chuan Wang Bin Hu Zhi-Xiong Xie Dai-Wen Pang The Institute for Advanced Studies College of Chemistry and Molecular SciencesCollege of Life SciencesHubei Key Laboratory of Cell HomeostasisWuhan UniversityWuhan 430072China Research Center for Analytical Sciences College of ChemistryState Key Laboratory of Medicinal Chemical BiologyTianjin Key Laboratory of Biosensing and Molecular RecognitionFrontiers Science Center for New Organic MatterFrontiers Science Center for Cell Responsesand Haihe Laboratory of Sustainable Chemical TransformationsNankai UniversityTianjin 300071China

Biosynthesized semiconductor quantum dots(QDs) have bright fluorescence,adjustable particle sizes,and environmental friendliness,endowing them with convenience and potential for biological *** to the unclear mechanism of the cellular environment on the live-cell synthesis of QDs,it is still difficult to regulate their optical ***,the critical role of the intracellular redox environment in regulating the fluorescence properties of biosynthesized CdSe QDs in Staphylococcus aureus(***) has been *** glutathione peroxidase(GPx) activity directly affects the intracellular H_(2)O_(2) produced in the SeO_(3)^(2-) reduction,which further manipulates the glutathione redox cycle to determine the content of low-valence *** a result,the fluorescence intensity of the synthesized CdSe QDs increases by 60% in the GPx overexpressed *** cellular redox potential that is controlled by the GSH redox cycle provides the driving force for the reduction of SeO_(3)^(2-),facilitating the synthesis of CdSe QDs in *** *** proposed mechanism of the cellular redox state provides a new perspective for regulating the synthesis of semiconductor nanomaterials in live cells.

关键词： redox H_(2)O_(2) peroxidase quantum dot Staphylococcus aureus

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Hawking-Page transition and the dual relations of anti-de Sitter black holes surrounded by dark energy in general dimensions

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Communications in Theoretical Physics 2024年第7期76卷 94-104页

作者： Zhang Xin xu wei School of Mathematics and Physics China University of GeosciencesWuhan 430074China

Recently,a dual relation T_(0)(n+1)=T_(HP)(n)between the minimum temperature(T_(0)(n+1))black hole phase and the Hawking-Page transition(T_(HP)(n))black hole phase in two successive dimensions was introduced by wei et al(2020 ***.D10210411);this was reminiscent of the anti-de Sitter/conformal field theory(AdS/CFT)correspondence,as the Hawking-Page transition temperature could be treated as the temperature of the dual physical quantity on the boundary and the latter corresponds to that in the *** this paper,we discuss the Hawking-Page transition and the dual relations in Ads black holes surrounded by dark energy in general *** findings reveal the occurrence of the Hawking-Page transition between the thermal AdS radiation and thermodynamically stable large AdS black holes,in both the spacetime surrounded by phantom dark energy and the spacetime surrounded by quintessence dark *** discuss the effects of the phantom dark energy and quintessence dark energy on the Hawking-Page transition *** the dual relation in particular,it works well for the case of an AdS black holes surrounded by phantom dark *** the case of an Ads black hole surrounded by quintessence dark energy,the dual relation should be modified under an open assumption that the state parameter and the density parameter of the quintessence dark energy depend on the dimensions of the spacetime.

关键词： Hawking-Page transition dark energy black hole thermodynamics

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Coupling effect on the thermal hazard assessment of hazardous chemical materials via calorimetric technologies and simulation approaches

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Defence Technology（防务技术） 2024年第2期32卷 644-654页

作者： Yabei xu jiankun Shao wei Wang Shengliang xu Dongping Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechnologyXiangyang 441003China

The coupling effect of heat absorption and release exists in the thermal decomposition of a few chemical ***,the impact of the above coupling on thermal hazard assessment is not considered in the literature *** this work,nitroguanidine(NQ)and 1,3,5-trinitro-1,3,5-triazine(RDX)are selected as representative materials to explore the influence of the coupling effect on the thermal hazard assessment of chemical *** linear heating experiments of NQ and RDX are carried out by a microcalorimeter and synchronous thermal *** thermal decomposition curves are decoupled by advanced thermokinetics *** thermal decomposition and kinetic parameters before and after decoupling are *** results of TG experiment show that both NQ and RDX began to lose mass during the endothermic *** endothermic melting and exothermic decomposition of NQ and RDX are coupled within this *** coupling effect has different degrees of influence on its initial decomposition temperature and safety *** with the parameters in the coupling state,the initial decomposition temperature and adiabatic induction period after decoupling *** self-accelerating decomposition temperature increases,and internal thermal runaway time *** the thermal hazard assessment of chemical materials with coupling effects,the calculated parameters after decoupling should be taken as an important safety index。

关键词： Calorimetric technologies Kinetics Thermal hazard Phase transformation Thermal decomposition

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Accelerated rise in wildﬁre carbon emissions from Arctic continuous permafrost

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Science Bulletin 2024年第15期69卷 2430-2438页

作者： Xingru Zhu Gensuo jia Xiyan xu Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Wildfires over permafrost put perennially frozen carbon at ***,wildfire emissions from biomass burning over the diverse range of permafrost regions and their share in global wildfire emissions have not been *** results showed a dramatic increase in wildfire carbon emissions from permafrost regions over the period 1997–*** share of permafrost in global wildfire CO_(2) emissions increased from 2.42%in 1997 to 20.86%in *** wildfire emissions from continuous permafrost region is the single largest contributor to increased emissions in northern permafrost ***-induced emissions from 2019 to 2021 alone accounted for approximately 40%of the 25-year total CO_(2) emissions from continuous permafrost *** rise in wildfire emissions from continuous permafrost regions is explained by desiccation within a 5–10 cm soil depth,where wildfires combust belowground *** findings highlight the acceleration of fire-induced carbon emissions from continuous permafrost regions,which disturb the organic carbon stock and accelerate the positive feedback between permafrost degradation and climate warming,thus stimulating permafrost towards a climatic tipping point.

关键词： Wildfire Permafrost Carbon Fuel moisture CO_(2) Continuous permafrost

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Requirements ranking based on crowd-sourcing high-end product USs

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Journal of Systems Engineering and Electronics 2024年第1期35卷 94-104页

作者： MA Yufeng DOU Yajie xu Xiangqian jia Qingyang TAN Yuejin College of Systems Engineering National University of Defense TechnologyChangsha 410003China

Based on the characteristics of high-end products,crowd-sourcing user stories can be seen as an effective means of gathering requirements,involving a large user base and generating a substantial amount of unstructured *** key challenge lies in transforming abstract user needs into specific ones,requiring integration and ***,we propose a topic mining-based approach to categorize,summarize,and rank product requirements from user ***,after determining the number of story categories based on py LDAvis,we initially classify“I want to”phrases within user ***,classic topic models are applied to each category to generate their names,defining each post-classification user story category as a ***,a weighted ranking function is devised to calculate the importance of each ***,we validate the effectiveness and feasibility of the proposed method using 2966 crowd-sourced user stories related to smart home systems.

关键词： high-end product complex system crowd-sourcing user stories topic mining requirements ranking

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Experimental investigation on weak shock wave mitigation characteristics of flexible polyurethane foam and polyurea

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Defence Technology（防务技术） 2024年第1期31卷 179-191页

作者： Shiyu jia Cheng Wang Wenlong xu Dong Ma Fangfang Qi State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Institute for Advanced Technology Shandong UniversityJinan250061China

In recent years,explosion shock wave has been considered as a signature injury of the current military *** strong shock wave is lethal to the human body,weak shock wave can cause many more lasting *** investigate the protection ability and characteristics of flexible materials and structures under weak shock wave loading,the blast wave produced by TNT explosive is loaded on the polyurethane foam with the density of 200.0 kg/m3(F-200)and 400.0 kg/m3(F-400),polyurea with the density of 1100.0 kg/m^(3)(P-1100)and structures composed of the two materials,which are intended for individual *** results indicate that the shock wave is attenuated to weak pressure disturbance after interacting with the flexible materials which are not *** shock wave protective capability of single-layer materials is dependent on their thickness,density and microscopic *** overpressure,maximum pressure rise rate and impulse of transmitted wave decrease exponentially with increase in sample *** the same thickness,F-400 provides better protective capability than F-200 while P-1100 shows the best protective capability among the three *** this study,as the materials are not destroyed,F-200 with a thickness more than10.0 mm,F-400 with a thickness more than 4.0 mm,and P-1100 with a thickness more than 1.0 mm can attenuate the overpressure amplitude more than 90.0%.Further,multi-layer flexible composites are *** layer layouts of designed structures and layer thickness of the single-layer materials can affect the protective *** the research range,the structure in which polyurea is placed on the impact side shows the optimal shock wave protective performance,and the thicknesses of polyurea and polyurethane foam are 1.0 mm and 4.0 mm *** overpressure attenuation rate reached maximum value of 93.3%and impulse attenuation capacity of this structure are better than those of s

关键词： Free-field explosion Weak shock wave mitigation Polyurea Polyurethane foam Multi-layered composites

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High-Order Decoupled and Bound Preserving Local Discontinuous Galerkin Methods for a Class of Chemotaxis Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 372-398页

作者： wei Zheng Yan xu School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

In this paper,we explore bound preserving and high-order accurate local discontinuous Galerkin(LDG)schemes to solve a class of chemotaxis models,including the classical Keller-Segel(KS)model and two other density-dependent *** use the convex splitting method,the variant energy quadratization method,and the scalar auxiliary variable method coupled with the LDG method to construct first-order temporal accurate schemes based on the gradient flow structure of the *** semi-implicit schemes are decoupled,energy stable,and can be extended to high accuracy schemes using the semi-implicit spectral deferred correction *** bound preserving DG discretizations are only worked on explicit time integration methods and are difficult to get high-order *** overcome these difficulties,we use the Lagrange multipliers to enforce the implicit or semi-implicit LDG schemes to satisfy the bound constraints at each time *** bound preserving limiter results in the Karush-Kuhn-Tucker condition,which can be solved by an efficient active set semi-smooth Newton *** numerical experiments illustrate the high-order accuracy and the effect of bound preserving.

关键词： Chemotaxis models Local discontinuous Galerkin(LDG)scheme Convex splitting method Variant energy quadratization method Scalar auxiliary variable method Spectral deferred correction method

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Computed tomography-based radiomics to predict early recurrence of hepatocellular carcinoma post-hepatectomy in patients background on cirrhosis

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World Journal of Gastroenterology 2024年第15期30卷 2128-2142页

作者： Gui-Xiang Qian Zi-Ling xu Yong-Hai Li jian-Lin Lu Xiang-Yi Bu Ming-Tong wei wei-Dong jia Department of Hepatic Surgery Anhui Provincial HospitalThe First Affiliated Hospital of USTCDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Hepatic Surgery Anhui Provincial Hospital Affiliated to Anhui Medical UniversityAnhui Medical UniversityHefei 230001Anhui ProvinceChina Department of Anorectal Surgery the First People’s Hospital of HefeiHefei 230001Anhui ProvinceChina

BACKGROUND The prognosis for hepatocellular carcinoma(HCC)in the presence of cirrhosis is unfavourable,primarily attributable to the high incidence of *** To develop a machine learning model for predicting early recurrence(ER)of posthepatectomy HCC in patients with cirrhosis and to stratify patients’overall survival(OS)based on the predicted risk of *** In this retrospective study,214 HCC patients with cirrhosis who underwent curative hepatectomy were *** feature selection was conducted using the least absolute shrinkage and selection operator and recursive feature elimination ***-radiologic features were selected through univariate and multivariate logistic regression *** machine learning methods were used for model comparison,aiming to identify the optimal *** model’s performance was evaluated using the receiver operating characteristic curve[area under the curve(AUC)],calibration,and decision curve ***,the Kaplan-Meier(K-M)curve was used to evaluate the stratification effect of the model on patient *** Within this study,the most effective predictive performance for ER of post-hepatectomy HCC in the background of cirrhosis was demonstrated by a model that integrated radiomics features and clinical-radiologic *** the training cohort,this model attained an AUC of 0.844,while in the validation cohort,it achieved a value of *** K-M curves illustrated that the combined model not only facilitated risk stratification but also exhibited significant discriminatory ability concerning patients’*** The combined model,integrating both radiomics and clinical-radiologic characteristics,exhibited excellent performance in HCC with *** K-M curves assessing OS revealed statistically significant differences.

关键词： Machine learning Radiomics Hepatocellular carcinoma Cirrhosis Early recurrence Overall survival Computed tomography Prognosis Risk factor Delta-radiomics

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Efficient Photolytic Halogenation and Oxidation of Unactivated Alkyl sp^(3) C—H Bonds with Iodine(III)

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Chinese Journal of Chemistry 2024年第5期42卷 505-510页

作者： Hao jia Nan Li Chunmei Tang Yajuan Wang Yonghao Xi Rongbao Liao wei xu Fufang Wu Xiaobao Shen Hongbin Zhai Biomass Oligosaccharides Engineering Technology Research Center of Anhui Province Engineering Research Center of Biomass Conversion and Pollution Prevention of Anhui Educational InstitutionsFuyang Normal UniversityFuyangAnhui236037 China Institute of Marine Biomedicine Shenzhen PolytechnicShenzhenGuangdong518055 China State Key Laboratory of Chemical Oncogenomics Shenzhen Engineering Laboratory of Nano Drug Slow-ReleasePeking University Shenzhen Graduate SchoolShenzhenGuangdong518055 China

A metal-free,green,and sustainable functionalization of unactivated alkyl sp^(3) C—H bonds is reported using iodine(III)as a feasible dehydrogenation agent under visible light or KBr,and alkyl chlorides,bromides,alcohols,and ketones could be constructed by addition of different coupling *** and safe iodobenzene diacetate was used to form a radical to activate the alkyl sp^(3) C—H bond in a highly efficient manner,which can construct different alkylation products by adding corresponding coupling reagents.

关键词： Alkyl sp^(3)C—H bonds Chlorination Bromination Oxidation Iodine(III) C—H activation Radical Photocatalysis

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Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

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Nuclear Science and Techniques 2024年第4期35卷 1-14页

作者： Dong Zhao xu-Wen Liang Ping-Kun Cai wei Cheng Wen-Bao jia Da-Qian Hei Qing Shan Yong-Sheng Ling Chao Shi Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of jiangsu Higher Education Institutions Suzhou 215000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a *** this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)*** imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded *** EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager *** difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position *** position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 *** DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution *** unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image *** method can effectively reduce image noise caused by poor DOI detector position *** vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关键词： Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging

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