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Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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Science China Chemistry 2024年第11期67卷 3798-3806页

作者： Qi-Chao Shan Yan Zhao Yong Wu Hong-Fei Liu Xin-Hua Duan Li-na Guo Department of Chemistry School of Chemistry Energy Research Center of Energy Storage Materials and Devices Ministry of EducationXi'an Jiaotong University State k.y Laboratory of Applied Organic Chemistry Lanzhou University

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alk.xyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic sk.letons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide sk.leton reverses the selectivity of C-C cleavage. Remark.bly, the photo and thermal assistance is not required when the succinimide sk.leton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and k.netically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alk.xy radical

Role of aminopeptidase N-lik. in the acquisition of begomoviruses by Bemisia tabaci,the whitefly vector

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Insect Science 2024年第3期31卷 707-719页

作者： Yun-Yun Fan Yao Chi na Chen Wilmer J.Cuellar Xiao-Wei Wang Ministry of Agriculture k.y Lab of Molecular Biology of Crop Pathogens and Insects Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang ProvinceInstitute of Insect SciencesZhejiang UniversityHangzhouChina Zhejiang Tianmushan national nature Reserve Administration HangzhouChina Institute of Plant Protection Liaoning Academy of Agricultural SciencesShenyangChina Virology Laboratory Cassava ProgramInternational Center for Tropical Agriculture(CIAT)PalmiraColombia

Sri Lank.n cassava mosaic virus(SLCMV)is a prominent causative agent of cassava mosaic disease in Asia and relies on the whitefly Bemisia tabaci cryptic complex for its ***,the molecular mechanisms involved in SLCMV transmission by *** have yet to be *** this study,we identified an aminopeptidase N-lik. protein(BtAPN)in *** Asia II 1,an efficient vector of SLCMV,which is involved in the SLCMV transmission *** the use of glutathione S-transferase pull-down assay and LC-MS/MS analysis,we demonstrated the interaction between BtAPN and the coat protein(CP)of *** interaction was further confirmed in vitro,and we observed an induction of BtAPN gene expression following SLCMV *** interfering with the function of BtAPN,the quantities of SLCMV were significantly reduced in various parts of *** Asia II 1,including the whole body,midgut,hemolymph,and primary salivary ***,we discovered that BtAPN is conserved in *** Middle East-Asia Minor 1(MEAM1)and interacts with the CP of tomato yellow leaf curl virus(TYLCV),a begomovirus k.own to cause severe damage to tomato *** BtAPN with antibody led to a significant reduction in the quantities of TYLCV in whitefly whole body and organs/*** results demonstrate that BtAPN plays a generic role in interacting with the CP of begomoviruses and positively regulates their acquisition by the whitefly.

关键词： BtAPN coat protein SLCMV TYLCV virus acquisition whitefly

Influences of Earth Incidence Angle on FY-3/MWRI SST Retrieval and Evaluation of Reprocessed SST

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Journal of Tropical Meteorology 2024年第3期30卷 230-240页

作者： ZHANG Miao CHEN Lin XU na CAO Guang-zhen k.y Laboratory of Radiometric Calibration and Validation for Environmental Satellites National Satellite Meteorological CenterChina Meteorological AdministrationBeijing 100081 China Innovation Center for FengYun Meteorological Satellite(FYSIC) Beijing 100081 China

Sea surface temperature(SST)is a crucial physical parameter in meteorology and *** study demonstrates that the influence of earth incidence angle(EIA)on the SST retrieved from the microwave radiation imager(MWRI)onboard FengYun-3(FY-3)meteorological satellites should not be *** with algorithms that do not consider the influence of EIA in the regression,those that integrate the EIA into the regression can enhance the accuracy of SST ***,based on the recalibrated Level 1B data from the FY-3/MWRI,a long-term SST dataset was reprocessed by employing the algorithm that integrates the EIA into the *** reprocessed SST data,including FY-3B/MWRI SST during 2010-2019,FY-3C/MWRI SST during 2013-2019,and FY-3D/MWRI SST during 2018-2020,were compared with the in-situ SST and the SST dataset from the Operational Sea Surface Temperature and Ice Analysis(OSTIA).The results show that the FY-3/MWRI SST data were consistent with both the in-situ SST and the OSTIA SST *** with the Copernicus Climate Change Service V2.0 SST,the absolute deviation of the reprocessed SST,with a quality flag of 50,was less than 1.5℃.The root mean square errors of the FY-3/MWRI orbital,daily,and monthly SSTs,with a quality flag of 50,were approximately 0.82℃,0.69℃,and 0.37℃,*** primary discrepancies between the FY-3/MWRI SST and the OSTIA SST were found mainly in the regions of the western boundary current and the Antarctic Circumpolar ***,this reprocessed SST product is recommended for El Niño and La Niña events monitoring.

关键词： FengYun-3 satellites sea surface temperature microwave radiation imager earth incidence angle reprocessing

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Magnetic properties of soft magnetic composites prepared by gas-atomized glassy powders from a new Fe-based alloy with high glass-forming ability

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 91-104页

作者： Ranbin Wang Jili Jia You Wu Wenhui Guo na Chen Yang Shao k.fu Yao School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Wuzhen Laboratory Tongxiang 314500China

With a pressing need for high efficiency, low power consumption, and miniaturization of electronics, soft magnetic composites(SMCs) show great potential, especially for applications in k.y electronic component. However, core loss is still the focused issue for SMCs that hinders their sustainable development and widespread applications. In the present study, high-performance SMCs were fabricated by novel Fe_(74)B_(7)C_(7)P_(7)Si_(3)Mo_(1)Cr_(1) powders with spherical shape and a fully glassy structure, which were successfully prepared by a gas atomization method. The microstructure and high-frequency magnetic properties of these SMCs were studied in detail. To enhance the soft ferromagnetism, the effects of annealing temperature(T_a) and powder size on their performance were clarified. Increasing T_a up to 703 k.not only helps to effectively release internal stress in the powders, but also improves the integrity of the insulation layer structure, which is conducive to decreasing the core loss. In addition, reducing the powder size contributes to the overall performance enhancement. Prepared from the powders with the smallest mean particle size and annealed at 703 k. the SMC exhibits optimum property combination of a stable effective permeability of 26.2 up to 1 MHz, a total core loss of 883 k. m^(–3)(100 k.z, 100 mT), and a DC-Bias performance of 79.3% under 100 Oe field, which is even comparable to those of the most prominent SMCs reported so far. These results are meaningful for potentially stimulating the development and application of new low-loss SMCs.

关键词： metallic glassy powder soft magnetic composite annealing temperature particle size high-frequency property

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Asynchronous gain-scheduled control of deepwater drilling riser system with hybrid event-triggered sampling and unreliable communication

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 272-285页

作者： na PANG Dawei ZHANG Shuqian ZHU School of Mathematics Shandong UniversityJinan250100China

This paper investigates the recoil control of the deepwater drilling riser system with nonlinear tension force and energy-bounded friction force under the circumstances of limited network.resources and unreliable *** from the existing linearization modeling method,a triangle-based polytope modeling method is applied to the nonlinear riser *** on the polytope model,to improve resource utilization and accommodate random data loss and communication delay,an asynchronous gain-scheduled control strategy under a hybrid event-triggered scheme is *** asynchronous linear parameter-varying system that blends input delay and impulsive update equation is presented to model the nonlinear network.d recoil control system,where the asynchronous deviation bounds of scheduling parameters are *** to the Lyapunov-k.asovsk.i functional method,some solvable conditions of disturbance attenuation analysis and recoil control design are derived such that the resulting network.d system is exponentially mean-square stable with prescribed H∞*** obtained numerical results verified that the proposed nonlinear network.d control method can achieve a better recoil response of the riser system with less transmission data compared with the linear control method.

关键词： Riser system Recoil control Asynchronous gain-scheduled control Data loss Event-triggered scheme

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Predictive effect of lipopolysaccharide-stimulated inflammatory cytok.nes on symptoms of generalized anxiety disorder

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World Journal of Psychiatry 2024年第9期14卷 1308-1318页

作者： Wen-Yuan Wang na Liu Xiao-Xiao Qi Bing Han Jing-na Sun Zheng-Li Chen Ming-Wei Wang Yan-Yong Wang Department of Neurology The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Neurology Hebei HospitalXuanwu HospitalCapital Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Neurological Examination at Treatment Center The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina Department of Clinical Laboratory The First Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACk.ROUND Generalized anxiety disorder(GAD)is a relatively common mental ***,inflammation,an important factor for the development of depression,has attracted increasing *** studies have shown that inflammatory cytok.nes can affect the pathophysiological processes of several nervous system *** hypothesized that there is a correlation between the levels of lipopolysaccharide(LPS)-stimulated inflammatory cytok.nes and the clinical symptoms of *** To investigate the predictive effect of LPS-stimulated inflammatory cytok.nes on symptoms of *** This was a cross-sectional study in which 89 patients with GAD diagnosed at The First Hospital of Hebei Medical University from January 2022 to December 2022 and 70 individuals without anxiety and depression(controls)during the same period were *** venous blood was collected from all the subjects in heparin tubes,and another 3 ml of blood was supplemented with LPS(10 ng/ml).The plasma levels of 12 cytok.nes[Interleuk.n(IL)-1β,IL-2,IL-4,IL-5,IL-6,IL-8,IL-10,tumor necrosis factor(TNF)-α,interferon(IFN)-γ,IL-17A,IL-12p70,and IFN-α]were *** Post-LPS stimulation,the levels of IL-1β,IL-6,IL-8,IL-10,and TNF-αin both the control and GAD groups were significantly elevated above those in the nonstimulated groups,with IL-6 and IL-8 showing mark.d *** in IL-8 and TNF-αwere statistically significant in the GAD group(Pnalysis revealed that TNF-αwas associated with mental anxiety,whereas IL-1β,IL-8,and IL-10 were associated with physical anxiety symptoms,with IL-10 showing a negative correlation with physical ***-6 was associated with both mental and physical aspects of *** The physical symptoms of GAD are related to infla

关键词： Lipopolysaccharide Cytok.ne Generalized anxiety disorder Inflammatory cytok.nes Anxiety

Numerical study on critical flow velocity of ice slurry in the pipe of ice source heat pump system

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Energy and Built Environment 2024年第4期5卷 607-614页

作者： Tao Wu na Zhu Zhigao Hu Zhenyu Luo Pingfang Hu Fei Lei School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhanHubei 430074China Hubei Fengshen Purification Air Conditioning Equipment Engineering Company Limited WuhanHubei 430074China

The traditional evaporator of water source heat pump system is easy to freeze when the water source temperature is too low in winter.A novel ice source heat pump system is proposed,which can use low temperature surface water to supply heat to *** of the k.y problems for safe transportation is velocity range of ice slurry in ice outlet *** order to study the critical flow velocity of ice slurry in the pipe,an Euler model of horizontal straight pipe and 90°elbow pipe were established by Fluent *** influence of five factors on the critical flow velocity of two k.nds of pipes,including initial ice pack.ng fraction,ice particle size,pipe diameter,length of straight pipe and radius curvature of elbow was *** found that the initial ice content should be controlled from 10%to 15%.The inlet flow rate was 20%higher than the critical flow rate under the most unfavorable *** particle size was less than 0.2 *** total length of ice discharge pipeline was less than 50 *** radius of the bend should be met the minimum requirements of the specification of the pipe used.

关键词： Ice slurry Ice pack.ng fraction Flow in pipeline Critical velocity

Brain protective effect of dexmedetomidine vs propofol for sedation during prolonged mechanical ventilation in non-brain injured patients

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World Journal of Psychiatry 2024年第3期14卷 370-379页

作者： Hong-Xun Yuan Li-na Zhang Gang Li Li Qiao Intensive Care Unit Peking University International HospitalBeijing 102206China Central Operating Room The Affiliated Beijing Chaoyang Hospital of Capital Medical UniversityBeijing 100020China

BACk.ROUND Dexmedetomidine and propofol are two sedatives used for long-term *** remains unclear whether dexmedetomidine provides superior cerebral protection for patients undergoing long-term mechanical *** To compare the neuroprotective effects of dexmedetomidine and propofol for sedation during prolonged mechanical ventilation in patients without brain *** Patients who underwent mechanical ventilation for>72 h were randomly assigned to receive sedation with dexmedetomidine or *** Richmond Agitation and Sedation Scale(RASS)was used to evaluate sedation effects,with a target range of-3 to *** primary outcomes were serum levels of S100-βand neuron-specific enolase(NSE)every 24 *** secondary outcomes were remifentanil dosage,the proportion of patients requiring rescue sedation,and the time and frequency of RASS scores within the target *** A total of 52 and 63 patients were allocated to the dexmedetomidine group and propofol group,*** data were comparable between *** significant differences were identified between groups within the median duration of study drug infusion[52.0(IQR:36.0-73.5)h vs 53.0(IQR:37.0-72.0)h,P=0.958],the median dose of remifentanil[4.5(IQR:4.0-5.0)μg/k./h vs 4.6(IQR:4.0-5.0)μg/k./h,P=0.395],the median percentage of time in the target RASS range without rescue sedation[85.6%(IQR:65.8%-96.6%)vs 86.7%(IQR:72.3%-95.3),P=0.592],and the median frequency within the target RASS range without rescue sedation[72.2%(60.8%-91.7%)vs 73.3%(60.0%-100.0%),P=0.880].The proportion of patients in the dexmedetomidine group who required rescue sedation was higher than in the propofol group with statistical significance(69.2%vs 50.8%,P=0.045).Serum S100-βand NSE levels in the propofol group were higher than in the dexmedetomidine group with statistical significance during the first six and five days of mechanical ventilation,respectively(all P<0.05).CONCLUSION Dexmedetomidine demonstrated

关键词： Dexmedetomidine Propofol Sedation Prolonged mechanical ventilation Brain protective

Optimal Operation Strategy of Electricity-Hydrogen Regional Energy System under Carbon-Electricity Mark.t Trading

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Energy Engineering 2024年第3期121卷 619-641页

作者： Jingyu Li Mushui Wang Zhaoyuan Wu Guizhen Tian na Zhang Guangchen Liu Inner Mongolia k.y Laboratory of Electrical Energy Conversion Transmission and Control Inner Mongolia University of TechnologyHohhot010080China School of Electric Power Inner Mongolia University of TechnologyHohhot010080China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing102206China

Given the“double carbon”objective and the drive toward low-carbon power,investigating the integration and interaction within the carbon-electricity mark.t can enhance renewable energy utilization and facilitate energy conservation and emission reduction ***,further research is necessary to explore operational optimization methods for establishing a regional energy system using Power-to-Hydrogen(P2H)technology,focusing on participating in combined carbon-electricity mark.t *** study introduces an innovative Electro-Hydrogen Regional Energy System(EHRES)in this *** system integrates renewable energy sources,a P2H system,cogeneration units,and energy storage *** core purpose of this integration is to optimize renewable energy utilization and minimize carbon *** study aims to formulate an optimal operational strategy for EHRES,enabling its dynamic engagement in carbon-electricity mark.t *** initial phase entails establishing the technological framework.of the electricity-hydrogen coupling system integrated with ***,an analysis is conducted to examine the operational mode of EHRES as it participates in carbon-electricity mark.t ***,the system scheduling model includes a stepped carbon trading price mechanism,considering the combined heat and power generation characteristics of the Hydrogen Fuel Cell(HFC).This facilitates the establishment of an optimal operational model for EHRES,aiming to minimize the overall operating *** simulation example illustrates that the coordinated operation of EHRES in carbon-electricity mark.t transactions holds the potential to improve renewable energy utilization and reduce the overall system *** result carries significant implications for attaining advantages in both low-carbon and economic aspects.

关键词： Regional energy system electro-hydrogen coupling carbon-electricity mark.t step carbon trading coordination and optimization