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不同临床标本分离CRE流行病学与耐药性研究

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中国现代药物应用 2024年第12期18卷 80-83页

作者：李华锋黎彩珍雷桂炎梁永祥新兴县人民医院检验科 527400 新兴县人民医院呼吸内科 527400

目的明确本地区医疗机构耐碳青霉烯类肠杆菌科细菌(CRE)流行病学特征和耐药性情况,为当地医疗机构防治CRE感染提供科学依据。方法应用Vitek2 Compact等设备对日常微生物检验的临床标本进行致病菌鉴定和药敏试验,遴选出CRE菌株,再进一步... 详细信息

目的明确本地区医疗机构耐碳青霉烯类肠杆菌科细菌(CRE)流行病学特征和耐药性情况,为当地医疗机构防治CRE感染提供科学依据。方法应用Vitek2 Compact等设备对日常微生物检验的临床标本进行致病菌鉴定和药敏试验,遴选出CRE菌株,再进一步进行耐药性分析,最后统计资料分析CRE的流行病学特征和耐药性情况。结果共收到微生物检验标本19298份,除去重复统计,共分离出91株CRE;其中大肠埃希氏菌24株、占26.4%,肺炎克雷伯氏菌46株、占50.5%,阴沟肠杆菌14株、占15.4%,其他7株、占7.7%;91株CRE中,产A类丝氨酸酶有38株、占41.8%,产B类金属酶有52株、占57.1%,产混合型丝氨酸酶和金属酶有1株、占1.1%;分离出CRE的痰标本占比最大、占49.5%(45/91),分离出CRE的呼吸内科标本占比最高、占26.4%(24/91);丁胺卡那和替加环素对CRE的敏感性最高,均为53.8%(49/91)。结论呼吸内科是CRE感染的主要科室,痰标本分离出CRE的几率最高,产B类金属酶是该医疗机构CRE主要的耐药机制,肺炎克雷伯氏菌是主要的CRE,丁胺卡那和替加环素仍然可用于抗CRE感染治疗。

关键词：耐碳青霉烯类肠杆菌科细菌感染:碳青霉烯酶耐药流行病学

Engineering Rubisco to enhance CO_(2) utilization

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Synthetic and Systems Biotechnology 2024年第1期9卷 55-68页

作者： Lei Zhao zhen cai Yin li Yanping Zhang CAS Key Laboratory of Microbial Physiological and Metabolic Engineering State Key Laboratory of Microbial ResourcesInstitute of MicrobiologyChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Seeds Research Syngenta Biotechnology ChinaZhong Guan Cun Life Science ParkBeijingChina

Ribulose-1,5-bisphosphate carboxylase/oxygenase(Rubisco)is a pivotal enzyme that mediates the fixation of CO_(2).As the most abundant protein on earth,Rubisco has a significant impact on global carbon,water,and nitrogen ***,the significantly low carboxylation activity and competing oxygenase activity of Rubisco greatly impede high carbon fixation *** review first summarizes the current efforts in directly or indirectly modifying plant Rubisco,which has been challenging due to its high conservation and limitations in chloroplast transformation ***,recent advancements in understanding Rubisco biogenesis with the assistance of chaperones have enabled successful heterologous expression of all Rubisco forms,including plant Rubisco,in *** breakthrough facilitates the acquisition and evaluation of modified proteins,streamlining the measurement of their ***,the establishment of a screening system in *** opens up possibilities for obtaining high-performance mutant enzymes through directed ***,this review emphasizes the utilization of Rubisco in microorganisms,not only expanding their carbon-fixing capabilities but also holding significant potential for enhancing biotransformation processes.

关键词： Rubisco Plant CO_(2)fixation Microbial Carbon fixation pathway Synthetic biology Enzyme engineering

Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： YANG zhen FU Yong li Chao cai Xi GUO Chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou *** mineral that makes up the polymetallic layer is related to the sedimentary *** analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of *** results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan *** isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional *** sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from ***,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

Microstructural Evolutions and Mechanical Properties of Energetic Al_(1) (TiZrNbTaMoCr)_(15) High-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 620-632页

作者： Xuan-Hong cai zhen-Hua Wang Ben Niu Jin-Feng li Qing Wang Show authors Key Laboratory of Materials Modification By Laser Ion and Electron Beams(Ministry of Education)Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of Materials China Academy of Engineering PhysicsMianyang621908China

The present study focuses on investigating the microstructural evolutions and mechanical properties of energetic Al_(1)(TiZrNbTaMoCr)_(15) refractory high-entropy alloys with the different heat treatments at low Al content state. It is found that even with a reduction in the Al content, the strength of these alloys remains unaffected at room temperature and high temperature, while the plasticity improves significantly. In particular, the coherent BCC/B_(2) microstructure with needle-like B_(2) nanoprecipitates dispersed into the BCC matrix is formed in 873 K-aged Al_(1)Ti_(6)Zr_(2)Nb_(3)Ta_(3)Mo_(0.5)Cr_(0.5) alloy. Therefore, this alloy exhibits the highest compression yield strength (σ_(YS) = 1333 and 717 MPa) at room temperature and 1073 K, respectively. After 973 K-aged, the coherent BCC/B_(2) microstructure underwent destabilization, and the B_(2) phase transforms into the brittle Zr5Al3 phase which then coarsens and dominates the microstructure of S3-AlTa_(3) alloy after 1073 K-aged. Moreover, these current alloys exhibit exceptionally high theoretical exothermic enthalpy (ΔH), surpassing 11606 J·g^(−1), which highlights their significant potential as innovative high-performance energetic structural materials.

关键词： Refractory high-entropy alloy Coherent microstructure Mechanical property Exothermic enthalpy

Durable Design of Superhydrophobic Coatings with TiO_(2)Particles and Al_(2)O_(3)Whiskers for the Enhanced Anti-icing Performance

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Journal of Bionic Engineering 2024年第3期21卷 1360-1374页

作者： Weilan liu Kunlong li Yizhou Shen Huanyu Zhao Yaru Ni Zeyu cai lingfeng Zhao zhen Wang Institute of Advanced Materials(IAM) School of Materials Science and EngineeringNanjing Tech UniversityNanjing211816China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China Aviation Industry Aerodynamics Research Institute of China Shenyang110000China

Superhydrophobic coatings with high non-wetting properties are widely applied in anti-icing ***,the micro-nanostructures on the surfaces of superhydrophobic coatings are fragile under external forces,resulting in reduced ***,mechanical strength and durability play a crucial role in the utilization of superhydrophobic *** this study,we employed a two-step spraying method to fabricate superhydrophobic FEVE-based coatings with exceptional mechanical durability,utilizing fluorinated TiO_(2)nanoparticles and fluorinated Al_(2)O_(3)microwhiskers as the *** composite coating exhibited commendable non-wetting properties,displaying a contact angle of 164.84°and a sliding angle of 4.3°.On this basis,the stability of coatings was significantly improved due to the interlocking effect of Al_(2)O_(3)*** 500 tape peeling cycles,500 sandpaper abrasion tests,and 50 kg falling sand impact tests,the coatings retained superhydrophobicity,exhibiting excellent durability and application ***,the ice adhesion strength on the coatings was measured at only 65.4 kPa,while the icing delay time reached 271.8 s at-15℃.In addition,throughout 500 freezing/melting cycles,statistical analysis revealed that the superhydrophobic coatings exhibited a freezing initiation temperature as low as-17.25℃.

关键词： Superhydrophobic coatings Anti-icing Mechanical durability

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： zhen-bing cai Chun-lin li Lei YOU Xu-dong CHEN li-ping HE Zhong-qing CAO Zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all *** the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact *** learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact *** forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and *** was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after *** analysis shows that the load and current have great influence on the predicted electrical contact *** wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during *** learning algorithms can predict the electrical contact performance after wear caused by these *** results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact *** reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean

关键词： electrical contact wear contact resistance machine learning(ML) neural network

CPL-active hybrid copper(Ⅰ)halides enabled by cation inclusion with chiral crown-ether

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Science China Chemistry 2024年第10期67卷 3283-3290页

作者： Peng Fan li-Xuan cai Xiao-Fang Duan Fan Yin Chen-Chen li Zhong-Hua Deng Xiao-zhen li Qing-Fu Sun College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117China Strait Institute of Flexible Electronics(Future Technologies) Fujian Key Laboratory of Flexible ElectronicsFujian Normal University and Strait Laboratory of Flexible ElectronicsFuzhou 350117China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian College University of Chinese Academy of SciencesFuzhou 350002China

Chiral hybrid metal halides with high photoluminescence quantum yield(PLQY)and superior dissymmetry factor(g_(lum))are promising candidates for circularly polarized luminescence(CPL)emitting ***,it is a great challenge to achieve both high g_(lum)and large ***,we report a new supramolecular strategy to fabricate chiral hybrid Cu(Ⅰ)-halides with nearunity quantum yields and intense CPL *** dissymmetry factor can be dramatically modulated by tuning the hostguest *** to the chirality and variable conformations of the host-guest complexes,a series of chiral[G@L^(R/S)]_(2)Cu_(4)I_(6)have been *** incorporation of different cations within the chiral L^(R/S)hosts leads to variations of packing modes along the c-axis and different extent of distortions in the[Cu_(4)I_(6)]_(2)-*** them,[H_(3)O@L^(R/S)]+cations are stacked based on Van der Waals interactions and hierarchically self-assemble into a right/left-handed helix in[H_(3)O@L^(R/S)]_(2)Cu_(4)I_(6),which results in a high g_(lum)of-7×10^(-3)and a large PLQY of 96.92%.Notably,[G@L^(R/S)]_(2)Cu_(4)I_(6)shows promising applications in single-component white light emitting diodes(WLEDs),exhibiting a maximum dissymmetry factor of-1.2×10^(-3).The effective host-guest complexation and oriented hierarchical self-assembly provide an effective strategy for the development of high-performance CPL materials.

关键词： host-guest interaction circularly polarized luminescence copper iodide cluster hierarchical self-assembly chirality

Clinical analysis of secondary penile cancer:a case series at a tertiary referral center in China

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Asian Journal of Andrology 2024年第2期26卷 225-226页

作者： Xiao-Yu li Chun-Ru Xu Xing Ji zhen-Peng Zhu zhen-Ke Guo Tian-Yu cai Jian lin Department of Urology Peking University First HospitalBeijing 100034China Institute of Urology Peking UniversityBeijing 100034China National Urological Cancer Center Beijing 100034China Beijing Key Laboratory of Urogenital Diseases(Male)Molecular Diagnosis and Treatment Center Beijing 100034China

Dear Editor,Secondary penile cancer is an extremely rare condition that refers to the metastasis of other malignancies to the *** are limited reports on secondary penile cancer in Asian populations,and perceptions about this disease are extremely *** reviewed and analyzed the data of patients diagnosed with secondary penile cancer based on the pathological findings at Peking University First Hospital in Beijing,China,aiming to expand the clinical reference for this rare disease.

关键词： cancer rare finding

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi lin Lu-Kun Feng Ya-Dong li Chao-Fan Chang cai-zhen Zhu Ming-liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT