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Induced Absolute Configuration of Achiral Tetradentate Ligands in Metal–Organic Frameworks for Circularly Polarized luminescence

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Chinese Journal of Chemistry 2024年第11期42卷 1260-1266页

作者： hong-Ru Fu dan-dan Ren Kun Zhang hong Chen Xiaoyan lu Qing-Rong Ding lu-Fang Ma College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyangHenan471934 China College of Materials&Chemical Engineering China Three Gorges UniversityYichangHubei443002 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian350002 China

The crystallization of chiral molecules is of great significance to understand the origin and evolution of hierarchical chirality and reveal the relationships between structural chirality and circularly polarized luminescence(CPL)***,we report two pairs of chiral metal–organic frameworks(MOFs)(DCF-17/LCF-17,DCF-18/LCF-18)by utilizing tetradentate ligands tetra(3-imidazoylphenyl)ethylene(TIPE)and 4,4'-[4',5'-bis[4-(4-pyridinyl)phenyl][1,1':2',1”-terphenyl]-4,4”-diyl]bis[pyridine](TPPP)as *** can be observed that the spontaneous resolution of the achiral ligands is converted into the induced resolution,and the ligands form the absolute configuration by using enantiopure camphoric acid(cam)as chiral induced reagent(CIR).As a result,the racemate MOFs can be driven to generate absolute homochiral *** two achiral MOFs[Cd(D-cam)(TPPP)_(0.5)](AF-1,AF=achiral framework)and[Cd(L-cam)(TPPP)_(0.5)](AF-2)were *** position disorder of D/L-cam skeleton causes the generation of nonchiralization,further leading to disappearance of symmetry breaking of *** the perspective of structure,this is the first report which reveals the chiral transfer and nonchiralization between chiral induced agents and tetradentate ***,DCF-17 and LCF-17 show CPL with luminescence dissymmetry factor(glum)of–1.0×10^(-2)and+9.2×10^(–3),*** work provides the useful evidences to reveal the induced chiral crystallization and the construction of CPL-active crystalline materials.

关键词： Metal-organic frameworks Circularly polarized luminescence Chirality induction Spontaneous resolution Chirality transfer

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Phosphine-catalyzed acyl-transfer of heteroaryl ketones for the construction of N-fused heterocycles

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Chinese Chemical Letters 2024年第3期35卷 252-256页

作者： Yu Zhang De-Rui Han dan Ye hong lu Hao Wei Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi'an 710069China

An inexpensive phosphine catalyst was used effectively for a transition-metal-free acyl-transfer of N-containing heteroaryl ketones for the rapid synthesis of N-fused *** key pre-aromatic spirocyclic intermediate initialized by the single electron transfer(SET)process of Togni's reagentⅡpromoted by the tertiary phosphine resulted in an intriguing and alternative tactic for the cleavage of C–C *** using inexpensive tertiary phosphine as the catalyst,this skeleton-reorganizing approach of N-containing heteroaryl ketones allows a streamlined assembly of complex N-fused heterocycles with broad functional group tolerance.

关键词： Phosphine catalysis Acyl-transfer N-Fused heterocycles C–C bond activation Aromatization

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Impact of thoracic paravertebral block and sufentanil on outcomes and postoperative cognitive dysfunction in thoracoscopic lung cancer surgery

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World Journal of Psychiatry 2024年第6期14卷 894-903页

作者： dan-dan Wang hong-Yu Wang Yan Zhu Xi-Hua lu Department of Anesthesiology The Affiliated Cancer Hospital of Zhengzhou University&Henan Cancer HospitalZhengzhou 450008Henan ProvinceChina

BACKGROUND Postoperative pain management and cognitive function preservation are crucial for patients undergoing thoracoscopic surgery for lung cancer(LC).This is achieved using either a thoracic paravertebral block(TPVB)or sufentanil(SUF)-based multimodal ***,the efficacy and impact of their combined use on postoperative pain and postoperative cognitive dysfunction(POCD)remain *** To explore the analgesic effect and the influence on POCD of TPVB combined with SUF-based multimodal analgesia in patients undergoing thoracoscopic radical resection for LC to help optimize postoperative pain management and improve patient *** This retrospective analysis included 107 patients undergoing thoracoscopic radical resection for LC at The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital between May 2021 and January *** receiving SUF-based multimodal analgesia(n=50)and patients receiving TPVB+SUF-based multimodal analgesia(n=57)were assigned to the control group and TPVB group,*** compared the Ramsay Sedation Scale and visual analog scale(VAS)scores at rest and with cough between the two groups at 2,12,and 24 h after *** levels of epinephrine(E),angio-tensin Ⅱ(Ang Ⅱ),norepinephrine(NE),superoxide dismutase(SOD),vascular endothelial growth factor(VEGF),transforming growth factor-β1(TGF-β1),tumor necrosis factor-α(TNF-α),and S-100 calcium-binding proteinβ(S-100β)were measured before and 24 h after *** Mini-Mental State Examination(MMSE)was administered 1 day before surgery and at 3 and 5 days after surgery,and the occurrence of POCD was monitored for 5 days after *** reactions were also *** There were no significant time point,between-group,and interaction effects in Ramsay sedation scores between the two groups(P>0.05).Significantly,there were notable time point effects,between-group differences,and interaction effects observed in VAS scores both at rest

关键词： Thoracic paravertebral block Sufentanil Thoracoscope Radical resection of lung cancer Postoperative cognitive dysfunction

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Laser manufacturing of spatial resolution approaching quantum limit

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Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang hong-Hua Fang Zhen-Ze Li dan Wang hong-Bo Sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size of<5 nm is *** underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident *** show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to *** a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

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Research on the flow stability and noise reduction characteristics of quasi-periodic elastic support skin

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Defence Technology（防务技术） 2024年第3期33卷 222-236页

作者： lu Chen Shao-gang Liu dan Zhao Li-qiang Dong Kai Li Shuai Tang Jin Cui hong Guo Department of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin150001China

To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise *** arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic *** this paper,a dynamic model of skin in a fluid environment is *** influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is *** results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow ***,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal *** results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.

关键词： Flow stability Quasi-period Flexible wall Elastic support element Hydrodynamic noise

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Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF_(2)H, CF_(2)H^(+), and :CF_(2) reactivities

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Science China Chemistry 2024年第3期67卷 953-962页

作者： Yuan-Qing Gu hong-Xin Long dan-dan Zhang Mei-Feng Ruan Guo-Kai Liu School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

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Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： hong HUANG dan WU Yuan WANG Zhen WANG Yu LIU College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track *** characteristics of the six hard-clustered ETCs with the highest membership coefficient are *** tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these *** landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one *** frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four *** surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying *** results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method

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A disk I/O optimized system for concurrent graph processing jobs

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Frontiers of Computer Science 2024年第3期18卷 13-29页

作者： Xianghao XU Fang WANG hong JIANG Yongli CHENG dan FENG Peng FANG School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Computer Science&Engineering University of Texas at ArlingtonArlingtonTX 76019USA College of Computer and Data Science Fuzhou UniversityFuzhou 350108China Zhejiang Lab Hangzhou 311121China

In order to analyze and process the large graphs with high cost efficiency,researchers have developed a number of out-of-core graph processing systems in recent years based on just one commodity *** the other hand,with the rapidly growing need of analyzing graphs in the real-world,graph processing systems have to efficiently handle massive concurrent graph processing(CGP)***,due to the inherent design for single graph processing job,existing out-of-core graph processing systems usually incur unnecessary data accesses and severe competition of I/O bandwidth when handling the CGP *** this paper,we propose GraphCP,a disk I/O optimized out-of-core graph processing system that efficiently supports the processing of CGP *** proposes a benefit-aware sharing execution model to share the I/O access and processing of graph data among the CGP jobs and adaptively schedule the graph data loading based on the states of vertices,which efficiently overcomes above challenges faced by existing out-of-core graph processing ***,GraphCP adopts a dependency-based future-vertex updating model so as to reduce disk I/Os in the future *** addition,GraphCP organizes the graph data with a Source-Sorted Sub-Block graph representation for better processing capacity and I/O access *** evaluation results show that GraphCP is 20.5×and 8.9×faster than two out-of-core graph processing systems GridGraph and GraphZ,and 3.5×and 1.7×faster than two state-of-art concurrent graph processing systems Seraph and GraphSO.

关键词： graph processing disk I/O concurrent jobs

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Vitamin D receptor gene polymorphisms and colorectal cancer risk:A systematic meta-analysis

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World Journal of Gastroenterology 2012年第14期18卷 1672-1679页

作者： Yong-Heng Bai hong lu, dan hong Cheng-Cheng Lin Zhen Yu Bi-Cheng Chen Wenzhou Key Laboratory of Surgery The First AffiliatedHospital of Wenzhou Medical College Wenzhou 325000 Zheji-ang Province China Laboratory Diagnostic Center The First AffiliatedHospital of Wenzhou Medical College Wenzhou 325000 Zheji-ang Province China Department of Gastrointestinal Surgery The First Af-filiated Hospital of Wenzhou Medical College Wenzhou 325000Zhejiang Province China

AIM:To investigate the relationship between polymorphisms present in the vitamin D receptor(VDR) gene and colorectal cancer risk,a systematic meta-analysis of population-based studies was ***:A total of 38 relevant reports published between January 1990 and August 2010 were identified,of which only 23 qualified for this meta-analysis based on our selection *** polymorphic variants of the VDR gene,including Cdx-2(intron 1e) and FokI(exon 2) present in the 5' region of the gene,and BsmI(intron 8),ApaI(intron 8),and TaqI(exon 9) sites present in the 3' untranslated region(UTR),were evaluated for possible associations with colorectalcancer *** manager 4.2 was used to perform statistical ***:In the meta-analysis performed,only the BsmI polymorphism was found to be associated with colorectal cancer *** particular,the BsmI B genotype was found to be related to an overall decrease in the risk for colorectal cancer [BB vs bb:odds ratio(OR) = 0.87,95% CI:0.80-0.94,P = 3 × 10-4;BB vs Bb + bb:OR = 0.90,95% CI:0.84-0.97,P = 5 × 10-4].Moreover,in subgroup analyses,the BsmI B genotype was significantly associated with colon cancer,and not rectal *** absence of between-study heterogeneity was also ***:A meta-analysis of 23 published studies identified the BsmI polymorphism of the VDR gene to be associated with an increased risk of colon cancer.

关键词：基因多态性维生素D受体大肠癌危险系统第2外显子结直肠癌 VDR

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Core and variable antimicrobial resistance genes in the gut microbiomes of Chinese and European pigs

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Zoological Research 2024年第1期45卷 189-200页

作者： Cui-hong Tong Zhi-Peng Huo lu Diao dan-Yu Xiao Ruo-Nan Zhao Zhen-Ling Zeng Wen-Guang Xiong Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation South China Agricultural UniversityGuangzhouGuangdong 510642China National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria College of Veterinary MedicineSouth China Agricultural UniversityGuangzhouGuangdong 510642China National Laboratory of Safety Evaluation(Environmental Assessment)of Veterinary Drugs South China Agricultural UniversityGuangzhouGuangdong 510642China National Reference Laboratory of Veterinary Drug Residues South China Agricultural UniversityGuangzhouGuangdong 510642China

Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial *** its importance,the characterization of ARGs and microbiome structures,as well as the identification of indicators for routine ARG monitoring in pig farms,are still lacking,particularly concerning variations in antimicrobial exposure in different countries or ***,metagenomics and random forest machine learning were used to elucidate the ARG profiles,microbiome structures,and ARG contamination indicators in pig manure under different antimicrobial pressures between China and *** showed that Chinese pigs exposed to high-level antimicrobials exhibited higher total and plasmid-mediated ARG abundances compared to those in European pigs(Pluating the risk of ARG contamination in pig farms.

关键词： Metagenomic Pig manure Antimicrobial pressure Antimicrobial resistance genes Microbiome

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