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Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin dong-sheng Ji Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

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Joint Probability Analysis and Prediction of Sea Ice Conditions in Liaodong Bay

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Journal of Ocean University of China 2024年第1期23卷 57-68页

作者： LIAO Zhenkun dong sheng TAO Shanshan HUA Yunfei JIA Ning College of Engineering Ocean University of ChinaQingdao 266100China Shuifa Planning and Design Co. Ltd.Jinan 250100China National Hazards Mitigation Service Beijing 100194China

Sea ice conditions in Liaodong Bay of China are often described by sea ice grades,which classify annual sea ice conditions based on the annual maximum sea ice thickness(AM-SIT)and annual maximum floating ice extent(AM-FIE).The joint probability distribution of AM-SIT and AM-FIE was established on the basis of their data pairs from 1949/1950 to 2019/2020 in Liaodong *** joint intensity index of the sea ice condition in the current year is calculated,and the joint classification criteria of the sea ice grades in past years are established on the basis of the joint intensity index series.A comparison of the joint criteria with the 1973 and 2022 criteria revealed that the joint criteria of the sea ice grade match well,and the joint intensity index can be used to quantify the sea ice condition over the years.A time series analysis of the sea ice grades and the joint intensity index sequences based on the joint criteria are then *** show a decreasing trend of the sea ice condition from 1949/1950 to 2019/2020,a mutation in 1990/1991,and a period of approximately 91 years of the sea ice *** addition,the Gray-Markov model(GMM)is applied to predict the joint sea ice grade and the joint intensity index of the sea ice condition series in future years,and the error between the results and the actual sea ice condition in 2020/2021 is small.

关键词： sea ice grade ice thickness floating ice extent Liaodong Bay copula

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Molecular recognition of cyclophanes in water

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Chinese Chemical Letters 2024年第5期35卷 32-44页

作者： Fang-Yuan Chen Wen-Chao Geng Kang Cai dong-sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China College of Chemistry Nankai UniversityTianjin 300071China

Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular *** mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular *** the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition *** them,cyclophanes represent an important family of macrocyclic receptors that have been extensively *** aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous *** by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous *** review provides an overview of cyclophane receptors designed to bind organic guests in *** categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and *** review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.

关键词： Biomimetic receptor Cyclophane Molecular recognition Hydrophobic effect High-affinity Macrocycles

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A family of quantum von Neumann architecture

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Chinese Physics B 2024年第8期33卷 56-61页

作者：王东升 CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We develop universal quantum computing models that form a family of quantum von Neumann architectures,with modular units of memory,control,CPU,and internet,besides input and *** family contains three generations characterized by dynamical quantum resource theory,and it also circumvents no-go theorems on quantum programming and *** universality,such a family satisfies other desirable engineering requirements on system and algorithm design,such as modularity and programmability,hence serves as a unique approach to building universal quantum computers.

关键词： von Neumann architecture quantum resource theory quantum computing

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Causal role of immune cells in obstructive sleep apnea hypopnea syndrome:Mendelian randomization study

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World Journal of Clinical Cases 2024年第7期12卷 1227-1234页

作者： Huang-Hong Zhao Zhen Ma dong-sheng Guan Department of Encephalopathy Henan Provincial Hospital of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Personnel The First Affiliated Hospital of Henan University of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Neurology Henan Provincial Hospital of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina

BACKGROUND Despite being one of the most prevalent sleep disorders,obstructive sleep apnea hypoventilation syndrome(OSAHS)has limited information on its immunologic *** immunological underpinnings of certain major psychiatric diseases have been uncovered in recent years thanks to the extensive use of genome-wide association studies(GWAS)and genotyping techniques using highdensity genetic markers(e.g.,SNP or CNVs).But this tactic hasn't yet been applied to *** a Mendelian randomization analysis,we analyzed the causal link between immune cells and the illness in order to comprehend the immunological bases of *** To investigate the immune cells'association with OSAHS via genetic methods,guiding future clinical *** A comprehensive two-sample mendelian randomization study was conducted to investigate the causal relationship between immune cell characteristics and *** statistics for each immune cell feature were obtained from the GWAS *** on 731 immune cell properties,such as morphologic parameters,median fluorescence intensity,absolute cellular,and relative cellular,was compiled using publicly available genetic *** results'robustness,heterogeneity,and horizontal pleiotropy were confirmed using extensive sensitivity *** Following false discovery rate(FDR)correction,no statistically significant effect of OSAHS on immunophenotypes was ***,two lymphocyte subsets were found to have a significant association with the risk of OSAHS:Basophil%CD33dim HLA DR-CD66b-(OR=1.03,95%CI=1.01-1.03,P<0.001);CD38 on IgD+CD24-B cell(OR=1.04,95%CI=1.02-1.04,P=0.019).CONCLUSION This study shows a strong link between immune cells and OSAHS through a gene approach,thus offering direction for potential future medical research.

关键词： Obstructive sleep apnea hypopnea syndrome Immunity Causal inference MR analysis Sensitivity

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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： Gang Li Xian-Ming Xiao Bo-Wei Cheng Chen-Gang Lu Yue Feng dong-sheng Li School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing100083 China

The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well *** the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were *** results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM *** pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,*** methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,*** with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption *** GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas *** the geological and geochemical conditions of shale gas formation a

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content Controlling factor

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Landsat Image-Based Spatiotemporal Variation Analysis of Erosion and Deposition off the Qingshuigou of the Yellow River Delta from 1984 to 2021

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Journal of Ocean University of China 2024年第5期23卷 1173-1184页

作者： dong sheng LI Songda TAO Shanshan College of Engineering Ocean University of China

Owing to climate change and human activity, the Qingshuigou of the Yellow River Delta(YRD) has undergone dynamic changes in erosion and deposition. Therefore, studying these changes is important to ensure ecological protection and sustainable development. In this study, the trend of erosion-deposition evolution in the Qingshuigou was investigated based on 38 coastline phases extracted from Landsat series images of the YRD at one-year intervals from 1984 to 2021. The periodicity of the scouring and deposition evolution was also analyzed using wavelet analysis. Results showed that the total area of the Qingshuigou was affected by deposition and erosion and that the fluctuation first increased and then decreased. The total area reached a maximum in 1993. The depositional area first increased and then decreased, whereas the overall erosion area decreased. Deposition and erosion areas showed periodic changes to some extent; however, the periodic signal intensity decreased. Furthermore, factors including channel morphological evolution and variations in water and sediment discharge affect the spatiotemporal dynamics of erosion and deposition processes. The application of nonconsistency tests finally revealed that deposition area and flushing magnitude exhibited non-stationarities, which are potentially attributed to impacts from climatic change drivers.

关键词： coastline erosion and deposition remote sensing wavelet analysis Yellow River Delta

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Bipolar hip arthroplasty using conjoined tendon preserving posterior lateral approach in treatment of displaced femoral neck fractures

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World Journal of Clinical Cases 2024年第6期12卷 1076-1083页

作者： Ting-Xin Yan sheng-Jie dong Bo Ning Yu-Chi Zhao Department of Joint Surgery Yantaishan HospitalYantai 264003Shandong ProvinceChina Department of Joint Surgery Dongying People's HospitalDongying 257091Shandong ProvinceChina

BACKGROUND Hip fractures account for 23.8%of all fractures in patients over the age of 75 *** than half of these patients are older than 80 *** hemiarthroplasty(BHA)was established as an effective management option for these *** approaches can be used for the BHA ***,there is a high risk of postoperative *** conjoined tendon-preserving posterior(CPP)lateral approach was introduced to reduce postoperative dislocation *** To evaluate the effectiveness and safety of the CPP lateral approach for BHA in elderly *** We retrospectively analyzed medical data from 80 patients with displaced femoral neck fractures who underwent *** patients were followed up for at least 1 *** the 80 patients,57(71.3%)were *** time to operation averaged 2.3 d(range:1-5 d).The mean age was 80.5 years(range:67-90 years),and the mean body mass index was 24.9 kg/m^(2)(range:17-36 kg/m^(2)).According to the Garden classification,42.5%of patients were typeⅢand 57.5%of patients were typeⅣ.Uncemented bipolar hip prostheses were used for all *** conjoined tendons,dislocations,and adverse complications during and after surgery were *** The mean postoperative follow-up time was 15.3 months(range:12-18 months).The average surgery time was 52 min(range:40-70 min)with an average blood loss of 120 mL(range:80-320 mL).The transfusion rate was 10%(8 of 80 patients).The gemellus inferior was torn in 4 patients(5%),while it was difficult to identify in 2 patients(2.5%)during *** posterior capsule was punctured by the fractured femoral neck in 3 patients,but the conjoined tendon and the piriformis tendon remained *** patients had stem varus greater than 3 degrees or femoral *** were no patients with stem subsidence more than 5 mm at the last *** postoperative dislocations were observed throughout the follow-up *** significance was found between preoperative an

关键词： Conjoined tendon preserving Bipolar hip arthroplasty Femoral neck fractures Postoperative dislocation Posterolateral approach

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Clinicopathological characteristics and typing of multilocular cystic renal neoplasm of low malignant potential

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World Journal of Clinical Cases 2024年第14期12卷 2332-2341页

作者： Wen-Long Gao Gang Li dong-sheng Zhu Yuan-Jie Niu Department of Urology The Second Hospital of Tianjin Medical UniversityTianjin 300211China Department of Pediatric Surgery The First People’s Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina

BACKGROUND Up until now,no research has been reported on the association between the cli-nical growth rate of multilocular cystic renal neoplasm of low malignant potential(MCRNLMP)and computed tomography(CT)imaging *** study sought to examine the correlation between them,with the objective of distin-guishing unique features of MCRNLMP from renal cysts and exploring effective management *** To investigate optimal management strategies of *** We retrospectively collected and analyzed data from 1520 patients,comprising 1444 with renal cysts and 76 with MCRNLMP,who underwent renal cyst decom-pression,radical nephrectomy,or nephron-sparing surgery for renal cystic disease between January 2013 and December 2021 at our *** of MC-RNLMP utilized the Bosniak classification for imaging and the 2016 World Health Organization criteria for clinical *** Our meticulous exploration has revealed compelling findings on the occurrence of ***,it comprises 1.48%of all cases involving simple renal cysts,5.26%of those with complex renal cysts,and a noteworthy 12.11%of renal tumors coexisting with renal cysts,indicating a statistically significant difference(P=0.001).Moreover,MCRNLMP constituted a significant 22.37%of the patient po-pulation whose cysts demonstrated a rapid growth rate of≥2.0 cm/year,whereas it only represented 0.66%among those with a growth rate below 2.0 cm/*** the 76 MCRNLMP cases studied,none of the nine patients who underwent subsequent nephron-sparing surgery or radical nephrectomy following renal cyst decompression experienced recurrence or *** the remaining 67 patients,who were actively monitored over a 3-year postoperative period,only one showed suspicious recurrence on CT *** MCRNLMP can be tentatively identified and categorized into three types based on CT scanning and growth rate *** treating MCRNLMP,partial nephrectomy is preferred,while rad

关键词： Renal cysts Multilocular cystic renal neoplasm of low malignant potential Computed tomography Diagnosis Treatment

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Applying dynamic light scattering to investigate the self-assembly process of DNA nanostructures

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Chinese Chemical Letters 2024年第3期35卷 316-320页

作者： Wei Yuan Gui-Zhi dong Hui Ning Xiang-Xiang Guan Jia-Feng Cheng Zi-Wei Shi Xiu-Ji Du Si-Wen Meng dong-sheng Liu Yuan-Chen dong CAS Key Laboratory of Colloid Interface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dandong Bettersize Instruments Ltd. Dandong 118000China Key Laboratory of Organic Optoelectronics&Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Department of Chemistry Renmin University of ChinaBeijing 100872China

Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional *** this work,temperature-controlled dynamic light scattering(DLS)strategy has been applied to study the global assembly process of DNA origami and DNA *** the temperature dependent size and intensity profiles,the self-assembly process of various DNA nanostructures with different morphologies have been well-studied and the temperature transition ranges could be *** advantage of the DLS information,rapid preparation of the DNA origami and the brick assembly has been realized through a constant temperature *** results demonstrate that the DLS-based strategy provides a convenient and robust tool to study the dynamic process of forming hieratical DNA structures,which will benefit understanding the mechanism of self-assembly of DNA nanostructures.

关键词： Dynamic light scattering Self-assembly process DNA nanostructures Temperature transition ranges Rapid preparation

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