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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance Composite
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Implementation of evidence-based practice among clinical nurses practicing at an oncology hospital in Vietnam:a cross-sectional study
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作者 Pham Thiet Ke Luu Thi Thuy +1 位作者 Tran Thi Hoang Oanh Nguyen Thi Thanh Tra 《Frontiers of Nursing》 2026年第1期147-154,共8页
Objective:To describe the implementation of evidence-based practice(EBP)and identify the associated factors among clinical nurses working at an oncology hospital in Central Vietnam.Methods:A cross-sectional study was ... Objective:To describe the implementation of evidence-based practice(EBP)and identify the associated factors among clinical nurses working at an oncology hospital in Central Vietnam.Methods:A cross-sectional study was conducted with 190 clinical nurses recruited from an oncology hospital in Central Vietnam.The self-administered Evidence-Based Practice Questionnaire(EBPQ)was employed to assess the nurses'knowledge/skills,attitudes,and implementation of EBP.Data analysis utilized descriptive statistics,the Mann-Whitney test,the Kruskal-Wallis test,and Spearman's rho correlation.Results:The mean total score for EBP implementation among the nurses was 29.52(SD=7.14)out of 42 scores.The most frequently undertaken activity was sharing evidence with colleagues,whereas finding relevant evidence was the least performed.The level of EBP implementation significantly varied based on the nurses'role types and their participation in related courses(P<0.05).Moreover,a strong positive correlation was observed between EBP implementation and both knowledge/skills(r=0.703,P<0.001)and attitudes toward EBP(r=0.536,P<0.001).Conclusions:The implementation of EBP by oncology nurses is generally moderate and is significantly positively correlated with their knowledge/skills and attitudes toward EBP.These findings underscore the importance of enhancing educational programs and facilitating suppor tive institutional policies to fur ther encourage the adoption of EBP among nurses. 展开更多
关键词 clinical nurses evidence-based practice evidence-based practice questionnaire ONCOLOGY oncology nurses
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Batch and continuous-flow asymmetric synthesis of d-pantothenic acid precursor enabled by immobilized ketoreductase mutant
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作者 Pan Hu Xiaofan Wu +6 位作者 Yi An Xianjing Zheng Liang Gao Yuan Tao Yajiao Zhang Zedu Huang Fener Chen 《Chinese Chemical Letters》 2026年第2期471-476,共6页
We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl(R)-pantothenate((R)-PaOEt),the direct precursor of d-pantothenic acid.Firstly,a ketoreductase mutant designated as ... We report an immobilized enzyme-catalyzed batch and continuous-flow synthesis of optically pure ethyl(R)-pantothenate((R)-PaOEt),the direct precursor of d-pantothenic acid.Firstly,a ketoreductase mutant designated as M2,carrying two-point mutations of F97L and M242F relative to the wild-type SSCR,was constructed by site-directed mutagenesis,exhibited simultaneously improved activity toward ethyl 2′-ketopantothenate(K-PaOEt)and isopropanol,and could effectively catalyze the stereoselective reduction of K-PaOEt to(R)-PaOEt by using isopropanol as the sacrificial co-substrate to regenerate NADPH.After screening six commercially available carriers,an amino resin LXTE-700 was identified as the best solid support for the immobilization of M2 via the glutaraldehyde activation method.Upon optimization of the immobilization process and reaction conditions,the fabricated immobilized enzyme M2@amino resin demonstrated excellent recyclability and reusability,with the complete conversion of K-PaOEt to(R)-PaOEt being still realized after 12 cycles of reuse.Finally,M2@amino resin-catalyzed synthesis of(R)-PaOEt was successfully implemented in continuous-flow,accomplishing a 6.3 times higher space-time yield than that with the batch synthesis(529.2 versus 84 g L^(-1) d^(-1)).Our developed flow biocatalysis system also features an outstanding operational stability,as evidenced by the 100%conversion rate achieved after 15 consecutive days of operation. 展开更多
关键词 Asymmetric synthesis Continuous flow synthesis Enzyme immobilization KETOREDUCTASE D-Pantothenic acid
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A Review of Evidence-Based Research on Rehabilitation Nursing after Joint Replacement Surgery
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作者 Ying Wang 《Journal of Clinical and Nursing Research》 2026年第1期41-47,共7页
With the intensification of population aging,knee and hip joint replacement surgeries have become core methods for treating end-stage joint diseases,with over a million cases performed globally each year.Postoperative... With the intensification of population aging,knee and hip joint replacement surgeries have become core methods for treating end-stage joint diseases,with over a million cases performed globally each year.Postoperative rehabilitation nursing,as a crucial aspect of enhancing surgical outcomes,reducing complications,and facilitating patients’return to normal life,has its scientific and effective protocols directly influencing patient prognosis.This article systematically reviews the core research findings on rehabilitation nursing after joint replacement surgery based on the concept of evidence-based medicine,aiming to provide references for the formulation of standardized and personalized rehabilitation nursing plans in clinical settings. 展开更多
关键词 Joint replacement surgery Rehabilitation nursing evidence-based medicine Functional recovery Complication prevention
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Research on the Impact of Evidence-Based Predictive Nursing on Elderly Cataract Patients During the Perioperative Period
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作者 Weijian Ma Lili Sun +1 位作者 Rong Zeng Yanling Liu 《Journal of Clinical and Nursing Research》 2026年第1期13-20,共8页
Objective:To explore the impact of evidence-based predictive nursing intervention on psychological stress and physiological indicator stability of elderly cataract patients during the perioperative period(1 day before... Objective:To explore the impact of evidence-based predictive nursing intervention on psychological stress and physiological indicator stability of elderly cataract patients during the perioperative period(1 day before surgery to 1 day after surgery),and to provide a basis for optimizing clinical nursing plans for elderly cataract surgery.Methods:A retrospective selection of 90 elderly patients(aged≥60 years)who underwent cataract surgery in the Ophthalmology Department of our hospital from August 2024 to December 2024 was conducted.They were divided into an observation group(n=45)and a control group(n=45)using a random number table method.The control group received routine nursing for cataract surgery,while the observation group implemented evidence-based predictive nursing intervention(including the establishment of a multidisciplinary evidence-based team,hierarchical psychological intervention,perioperative environment optimization,intraoperative personalized cooperation,and video-based health education).Psychological stress indicators[Self-Rating Anxiety Scale(SAS),Self-Rating Depression Scale(SDS),General Self-Efficacy Scale(GSES)]on the 1st day before surgery and 1st day after surgery,and fluctuations of physiological indicators[Heart Rate(HR),Systolic Blood Pressure(SBP),Diastolic Blood Pressure(DBP)]on the 1st day before surgery and during surgery were compared between the two groups.Results:Before intervention,there were no statistically significant differences in SAS,SDS,GSES scores,HR,SBP,or DBP between the two groups(p>0.05);after intervention,the SAS score(33.62±5.72)and SDS score(32.14±4.86)of the observation group on the 1st day after surgery were significantly lower than those of the control group[(41.05±5.56),(43.59±4.75)],and the GSES score(31.15±3.28)was significantly higher than that of the control group(24.84±3.52)(all p<0.05);during surgery,the fluctuations of HR(74.0±6.0)beats/min,SBP(127.0±15.8)mmHg,and DBP(75.0±5.9)mmHg in the observation group were significantly smaller than those in the control group(all p<0.05).Conclusion:Evidence-based predictive nursing intervention can effectively alleviate anxiety and depression in elderly cataract patients during the perioperative period,improve self-efficacy,stabilize intraoperative physiological status,and enhance surgical cooperation,which is worthy of clinical promotion. 展开更多
关键词 evidence-based nursing Predictive nursing Elderly patients CATARACT Perioperative period Psychological stress Physiological stability SELF-EFFICACY
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Total synthesis of ADPr-ATP and evaluation of the antiviral activity of pRib-AMP prodrug
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作者 Tiantian Zhang Hanbo Liu +1 位作者 Junbiao Chang Yonggang Meng 《Chinese Chemical Letters》 2026年第2期419-423,共5页
ADPr-ATP is a natural nucleotide with three sugar rings and five pentavalent phosphorus,and can be produced through TIR-catalyzed ADP-ribosylation reactions for plant immunity.Here,we report the first total synthesis ... ADPr-ATP is a natural nucleotide with three sugar rings and five pentavalent phosphorus,and can be produced through TIR-catalyzed ADP-ribosylation reactions for plant immunity.Here,we report the first total synthesis of ADPr-ATP(1)with a total yield of 6.4%through 14 steps,featuring late-stage P(V)−N activation reaction of pyrophosphate(4)and 5′-phosphoromorpholidate(25).The protected adenosine 5′-phosphoromorpholidate(24)was prepared on the basis of a scalable to adenosine 5′′-monophosphate(2).The construction of P(V)−N bond in phosphoramidate is esteemed as a critical step as they are sufficiently stable in deprotection reactions.The chemical synthesis of ADPr-ATP can offer an appealing alternative to traditional enzymatic synthesis and fractionation methods.Furthermore,the pRib-AMP and its prodrug are also synthesized to evaluate cytotoxicity and anti-influenza activity in vitro. 展开更多
关键词 ADPr-ATP NUCLEOTIDE IMMUNITY Total synthesis ANTI-INFLUENZA
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Synthesis of transition metal nitride nanomaterials for electrocatalytic applications
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作者 Shuai Zhang Yiming Wang +2 位作者 Jiezhou Wang Xixi Wang Yiyao Ge 《Science China Materials》 2026年第3期1291-1316,共26页
Transition metal nitrides(TMNs)have been considered as promising alternative catalysts to noble metals in various electrocatalytic applications due to their noble metal-like electronic structures,high conductivity,low... Transition metal nitrides(TMNs)have been considered as promising alternative catalysts to noble metals in various electrocatalytic applications due to their noble metal-like electronic structures,high conductivity,low cost,as well as strong chemical stability,which could resist corrosion and oxidation in harsh operation conditions.Therefore,the rational design and controlled synthesis of TMNs with distinct structures play a vital role in developing highly efficient electrocatalysts toward electrochemical applications.This review provides a comprehensive summary of representative synthetic strategies for TMNs,such as direct nitridation,solidstate reaction,sol-gel assisted reaction,and wet-chemical reaction,presents the distinct structural characterizations,and demonstrates their advances in the electrochemical applications.Finally,we propose the remaining challenges and the future research directions on the exploration of TMNs with well-defined structures for electrocatalytic applications,which could shed light on the future development of high-performance electrocatalysts. 展开更多
关键词 ELECTROCATALYSTS transition metal nitrides controlled synthesis NANOMATERIALS
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Enantioconvergent reductive amidation of benzyl ammonium salts for synthesis of α-chiral amides
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作者 Saima Perveen Xicheng Wang +6 位作者 Tao Li Linghua Wang Shuai Zhang Yizhao Ouyang Xue Zhao Liang Xu Pengfei Li 《Chinese Chemical Letters》 2026年第1期300-305,共6页
α-Chiral amides are common in pharmaceuticals,agrochemicals,natural products,and peptides,prompting the need for new synthetic methods.Here,we introduce a nickel-catalyzed asymmetric reductive amidation method to syn... α-Chiral amides are common in pharmaceuticals,agrochemicals,natural products,and peptides,prompting the need for new synthetic methods.Here,we introduce a nickel-catalyzed asymmetric reductive amidation method to synthesizeα-chiral amides from benzyl ammonium salts and isocyanates.The key to success is using a chiral 2,2-bipyridine ligand(-)-Ph-SBpy,enabling high yield(up to 95%)and enantiomeric ratio(up to 98:2 er)under mild conditions.Addition of phenol prevents isocyanate polymerization by reversibly forming a carbamate intermediate,enhancing selectivity and efficiency.The synthetic utility is showcased through transformations of the enantioenriched amides,and the mechanism and enantioselectivity are supported by experimental and computational studies. 展开更多
关键词 α-Chiral amide AMIDATION Asymmetric synthesis Bipyridine ligand Nickel catalysis
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Scalable and rapid liquid synthesis of PtNi electrocatalyst for hydrogen evolution reaction
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作者 Liming Li Yanchang Liu +7 位作者 Peng Kang Donghui Feng Yuguang Zhang Hangxing Ren Jianrong Zeng He Zhu Qiang Li Xiaoya Cui 《Chinese Chemical Letters》 2026年第2期517-522,共6页
Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparti... Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparticles with a refined size of 2.71 nm and regular strains loaded on carbon black,synthesized using the high-temperature liquid shock(HTLS)method.This approach offers significant advantages over conventional synthesis methods,including high scalability,rapid reaction rates,and precise control over the size and shape of nanocrystals.Importantly,the synthesized PtNi electrocatalysts demonstrate outstanding catalytic activity and long-term stability for HER,achieving low overpotentials of 19 and 203 mV at current densities of 10 and 1000 mA/cm^(2),respectively.The superior performance can be attributed to the combination of a refined particle size,lattice strains,and synergistic effects between Pt and Ni.This rapid liquid-state synthesis demonstrated here holds great potential for scalable and industrial manufacturing of micro-/nano-catalysts. 展开更多
关键词 Hydrogen evolution reaction High-temperature liquid shock Pt-based nanocatalysts Rapid synthesis ELECTROCATALYST
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Precise synthesis of ortho-deuterated aromatic derivatives:An arylthianthrenium salt-based platform approach
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作者 Yunhao Guan Xia Peng +3 位作者 Rong Fan Xiaoying Feng Hongguang Du Jiajing Tan 《Chinese Chemical Letters》 2026年第1期259-265,共7页
The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid ... The deuterium labeling has garnered significant interest in drug discovery due to its critical role on improving pharmacokinetic and metabolic properties.However,despite its pharmaceutical value,the general and rapid syntheses of aromatic scaffolds that contains deuterium remain an important yet elusive task.State-of-the-art approaches mainly relied on the transition metal-catalyzed C-H deuteration via the assistance of directing groups(DGs),which often suffered from over-deuteration and lengthy step counts required for installation and/or removal of DG.Herein,we report a generalizable synthetic linchpin strategy for the facile preparation of the ortho-deuterated aromatic core.Through capture of aryne-derived 1,3-zwitterion with heavy water,we synthesized an array of ortho-deuterated aryl sulfonium salts.These novel linchpins not only participated the transition metal catalyzed cross-coupling reaction as nucleophiles,but also served as aryl radical reservoirs under photochemical or electrochemical conditions,enabling facile and precise access to structurally diverse deuterated aromatics.Moreover,we have disclosed a novel EDA complex enabled direct arylation of phosphines under visible-light irradiation,further expanding the utility of our platform approach. 展开更多
关键词 Deuterium labeling Thianthrenium salts Precise synthesis Linchpin strategy Aryne chemistry Organosulfur chemistry
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Effects of changing assimilate supply on starch synthesis in maize kernels under high temperature stress
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作者 Teng Li Shumei Wang +5 位作者 Qing Liu Xuepeng Zhang Lin Chen Yuanquan Chen Wangsheng Gao Peng Sui 《Journal of Integrative Agriculture》 2026年第2期639-647,共9页
High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assim... High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assimilate supply or direct inhibition on kernel metabolism.To clarify these mechanisms,a heat-sensitive maize hybrid,Xianyu 335 (XY),was exposed to 30℃/20℃ (maximum/minimum temperature,control) and 40℃/30℃ for seven consecutive days during the seed setting stage.Synchronous pollination (SP),apical pollination (AP),and shading treatments were applied to manipulate the inherent source–sink ratio in maize plants.Results showed that apical kernel weight decreased by 11.9%under 40℃ in the SP treatment.The ^(13)C content,starch accumulation,and cell-wall invertase (CWIN) activity also declined by 15.9,36.7,and 16.4%,respectively,under HT.In the shading treatment,40℃/30℃ caused even greater reductions in^(13)C content,starch accumulation,and CWIN activity due to diminished assimilate supply.Conversely,in the AP treatment,starch content and CWIN activity increased by 22.0 and 18.5%,respectively,under 40℃/30℃,resulting in kernel weight and ^(13)C content similar to those in SP and shading treatments regardless of temperature.Consistent with apical kernels under AP,HT did not negatively affect middle kernels in either SP or shading treatments,as kernel weight and starch content remained unchanged under HT.Although all kernels were exposed to the same HT or control environment,their responses varied a lot.The impaired starch synthesis in apical kernels under HT was rescued by increasing carbon supply via AP treatment.The contrasting performance among middle kernels,apical kernels under AP,and apical kernels under SP or shading indicates that reduced carbon supply is a critical factor underlying inhibited starch accumulation.Our findings provide a theoretical basis for further understanding kernel abortion under HT. 展开更多
关键词 high temperature stress MAIZE seed setting stage cell wall invertase starch synthesis
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A comprehensive review on oxygen vacancies modified catalysts:Synthesis,characterization,and crucial role in catalytic ozonation
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作者 Fengchen Wang Yujia Xiang +9 位作者 Yuqi Zhang Xin Zhou Jing Zhang Chuanshu He Heng Zhang Zhaokun Xiong Peng Zhou Hongyu Zhou Yang Liu Bo Lai 《Chinese Chemical Letters》 2026年第2期253-262,共10页
Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for... Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for additional energy input.Enhancing catalyst activity by introducing oxygen vacancies has been used extensively in heterogeneous catalytic ozonation.This paper reviews prevalent methods for the construction and characterization of oxygen vacancies.Based on a thorough examination of existing research,the role of oxygen vacancies is categorized according to their primary mechanisms of action in heterogeneous catalytic ozonation.For example,modulation of the catalyst electronic structure to enhance electron transfer;participation in the reaction as an active site to generate radicals and non-radicals;and exposure of more metal sites to enhance the reaction.Lastly,the paper delineates the limitations and future research directions concerning the role of oxygen vacancies in catalytic ozonation.This review addresses the gap in existing literature concerning the role of oxygen vacancies in catalytic ozone systems,establishes a comprehensive theoretical framework to aid in the design of efficient ozone catalysts,and delves into the functionality of oxygen vacancies in heterogeneous catalytic ozone reactions. 展开更多
关键词 Catalytic ozonation Bulk defects Surface defects Oxygen vacancies Degradation mechanism synthesis and characterization
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Chemical synthesis of the highly functionalized O-antigen repeating unit from Pseudomonas aeruginosa serotype O3 for glycoconjugate vaccine development
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作者 Guochao Lv Guangzong Tian +7 位作者 Guodong Chen Shengyong Zhu Jialong Bao Chunjun Qin Xiaopeng Zou Jing Hu Peter H.Seeberger Jian Yin 《Chinese Chemical Letters》 2026年第2期379-385,共7页
Pseudomonas aeruginosa is an opportunistic pathogen responsible for severe nosocomial infections.This multidrug-resistant bacterium can cause pneumonia and cystic fibrosis,both of which are associated with high morbid... Pseudomonas aeruginosa is an opportunistic pathogen responsible for severe nosocomial infections.This multidrug-resistant bacterium can cause pneumonia and cystic fibrosis,both of which are associated with high morbidity and mortality rates.The lipopolysaccharide of P.aeruginosa serves as an attractive target for the development of effective glycoconjugate vaccines.In this article,we report the first chemical synthesis of the highly challenging tetrasaccharide repeating unit of the P.aeruginosa serotype O3 O-antigen using a two-directional[1+(2+1)]glycosylation strategy.The synthesis is particularly challenging due to the poor nucleophilicity of the axial C4 hydroxyl group of l-galactose and the steric hindrance imposed by the 3S-hydroxybutyryl(Hb)chain.Furthermore,the presence of an acetyl group at the ortho position relative to the glycosylation site on l-galactose can lead to undesirable acetyl migration.Additionally,it is noteworthy that the selective removal of a 2-naphthylmethyl ether(Nap)during the late stages of synthesis,particularly in the presence of multiple benzyl groups,can be somewhat challenging to predict.Through the careful selection of synthetic strategies,building blocks,and optimized reaction conditions,we achieved the stereoselective glycosylations,selective oxidation of primary alcohols,remarkable enhancement of acceptor activity,and efficient introduction of the 3S-Hb group.The synthetic methodology presented in this work serves as a valuable reference for the preparation of structurally related oligosaccharides.By incorporating an aminopropyl linker,the target tetrasaccharide facilitates glycan microarray preparation and in vivo immunological assessments,thereby accelerating progress toward a synthetic glycoconjugate vaccine for P.aeruginosa. 展开更多
关键词 Chemical synthesis Pseudomonas aeruginosa Lipopolysaccharide Steric hindrance Poor nucleophilicity Acetyl migration Glycoconjugate vaccines
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Beyond origin:multimodal AI synthesis to resolve cancers of unknown primary
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作者 Hongru Shen Xiangchun Li 《Cancer Biology & Medicine》 2026年第1期21-29,共9页
For decades,the central dogma of oncology has been that a cancer’s identity is inextricably linked to its anatomical origin.This principle underpins the entire diagnostic and therapeutic framework,from histology-base... For decades,the central dogma of oncology has been that a cancer’s identity is inextricably linked to its anatomical origin.This principle underpins the entire diagnostic and therapeutic framework,from histology-based classification to site-specific treatment guidelines.Yet,this framework catastrophically fails for a substantial population of patients diagnosed with cancer of unknown primary(CUP).These patients present metastatic disease,yet their primary tumors remain elusive despite exhaustive clinical workup1.CUP,accounting for 1%-3%of all cancer diagnoses,is an enigma with devastating consequences;the median overall survival is only 2-12 months2-4.The inability to pinpoint an origin forces clinicians to rely on broad-spectrum empirical chemotherapy,such as taxane-carboplatin regimens,which have limited efficacy and exclude patients from the promise of targeted therapies and clinical trials5.CUP is not only a diagnostic challenge but also an indictment of the siloed approach to understanding malignancy:this cancer highlights the limitations of origin-based diagnostic frameworks.However,the confluence of high-dimensional biological data and advanced artificial intelligence(AI)is now poised to address this long-standing diagnostic limitation and to herald a new era for not only CUP but also oncology as a whole(Figure 1). 展开更多
关键词 central dogma oncology cancer unknown primary high dimensional biological data clinical trials diagnostic framework artificial intelligence targeted therapies multimodal AI synthesis
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Advances and challenges in the synthesis of N-fluoroalkyl compounds
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作者 Lvqi Jiang Wenbin Yi 《Science China Chemistry》 2026年第2期535-538,共4页
The incorporation of small fluorinated functional groups,including CF_(3),CF_(2)H,and CFH_(2),into small molecules represents a crucial strategy for modulating their physical,chemical,and biological characteristics[1,... The incorporation of small fluorinated functional groups,including CF_(3),CF_(2)H,and CFH_(2),into small molecules represents a crucial strategy for modulating their physical,chemical,and biological characteristics[1,2].Consequently,organofluorine compounds are frequently encountered in pharmaceuticals and agrochemicals.Significant advances have been made in the introduction of fluoroalkyl groups into small molecules since the beginning of the 21st century. 展开更多
关键词 introduction fluoroalkyl groups incorporation small fluorinated functional groupsincluding synthesis N fluoroalkyl compounds fluoroalkyl compounds fluorinated functional groups CF H small molecules
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Microwave-enabled rapid,continuous,and substrate-free synthesis of few-layer graphdiyne nanosheets for enhanced potassium metal battery performance 被引量:1
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作者 KONG Ya ZHANG Shi-peng +6 位作者 YIN Yu-ling ZHANG Zi-xuan FENG Xue-ting DING Feng ZHANG Jin TONG Lian-ming GAO Xin 《新型炭材料(中英文)》 北大核心 2025年第3期642-650,共9页
Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.... Graphdiyne(GDY)is a two-dimensional carbon allotrope with exceptional physical and chemical properties that is gaining increasing attention.However,its efficient and scalable synthesis remains a significant challenge.We present a microwave-assisted approach for its continuous,large-scale production which enables synthesis at a rate of 0.6 g/h,with a yield of up to 90%.The synthesized GDY nanosheets have an average diameter of 246 nm and a thickness of 4 nm.We used GDY as a stable coating for potassium(K)metal anodes(K@GDY),taking advantage of its unique molecular structure to provide favorable paths for K-ion transport.This modification significantly inhibited dendrite formation and improved the cycling stability of K metal batteries.Full-cells with perylene-3,4,9,10-tetracarboxylic dianhydride(PTCDA)cathodes showed the clear superiority of the K@GDY anodes over bare K anodes in terms of performance,stability,and cycle life.The K@GDY maintained a stable voltage plateau and gave an excellent capacity retention after 600 cycles with nearly 100%Coulombic efficiency.This work not only provides a scalable and efficient way for GDY synthesis but also opens new possibilities for its use in energy storage and other advanced technologies. 展开更多
关键词 Graphdiyne Microwave-assisted synthesis Few-layer Potassium metal battery Dendrite-free
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Evidence-based control of stress response on intraoperative physiological indexes and recovery of patients undergoing gastrointestinal surgery 被引量:3
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作者 Chen-Dong Yuan Bao-Zhu Zhou +2 位作者 Ning-Yan Wang Qing-Qing Wan Zhen-Zhen Hu 《World Journal of Gastroenterology》 2025年第8期72-81,共10页
BACKGROUND Although the 2021 Chinese Clinical Practice Guidelines for Enhanced Recovery after Surgery(ERAS)provide recommendations for ERAS in gastrointestinal surgery,the clinical application of standard ERAS nursing... BACKGROUND Although the 2021 Chinese Clinical Practice Guidelines for Enhanced Recovery after Surgery(ERAS)provide recommendations for ERAS in gastrointestinal surgery,the clinical application of standard ERAS nursing models is challenging due to the variety of diseases involved in gastrointestinal surgery and the com-plex factors contributing to patient stress responses.Moreover,stress responses are more severe in older adult patients.Therefore,precision medicine is required to improve the quality of nursing care and promote postoperative recovery in gastrointestinal surgery.and demonstrate nursing benefits through clinical practice.METHODS This randomized clinical trial first established an evidence-based nursing ERAS protocol in older adult patients based on literature related to perioperative nursing measures for gastrointestinal surgery stress response.Next,392 older adult patients who underwent gastrointestinal surgery and were admitted to our hospital between December 2021 and June 2023 were categorized into two groups to receive evidence-based(study group)or conventional(control group)ERAS nursing models,respectively.Intraoperative physiological parameters during surgery and postoperative recovery indicators were compared between the groups.RESULTS Among 64 domestic and international studies,the stress responses of older adult patients mainly included emotional anxiety,sleep disorders,gastrointestinal discomfort,physical weakness,pain,and swelling.The appropriate nursing interventions included comprehensive psychological counseling,pre-and postoperative nutritional support,temperature control,pain management,and rehabilitation training.Compared with the control group,the study group showed lower heart rate,mean arterial pressure,blood glucose level,and adrenaline level;shorter duration of drainage tube placement,time to first flatus,time to first ambulation,and postoperative hospital stay;lower anxiety scores on postoperative day 3;and lower incidences of postoperative infection,obstruction,poor wound healing,and gastrointestinal reactions were lower in the study group(all P<0.05).CONCLUSION The evidence-based nursing measures targeting stress responses based on the conventional ERAS nursing model resulted in stable intraoperative physiological parameters during surgery,promoted postoperative recovery,and reduced the incidence of complications. 展开更多
关键词 Older adult patients Gastrointestinal surgery Stress response evidence-based nursing Enhanced recovery after surgery
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Strategies and Advances in the Biomimetic Synthesis of Natural Products 被引量:1
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作者 Li-Jun Hu Zhi-Zhang Duan +2 位作者 Ying Wang Wen-Cai Ye Chun-Tao Che 《Engineering》 2025年第1期30-36,共7页
Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug... Natural products,with their remarkable structural and biological diversity,have historically served as a vital bridge between chemistry,the life sciences,and medicine.They not only provide essential scaffolds for drug discovery but also inspire innovative strategies in drug development.The biomimetic synthesis of natural products employs principles from biomimicry,applying inspiration from biogenetic processes to design synthetic strategies that mimic biosynthetic processes.Biomimetic synthesis is a highly efficient approach in synthetic chemistry,as it addresses critical challenges in the synthesis of structurally complex natural products with significant biological and medicinal importance.It has gained widespread attention from researchers in chemistry,biology,pharmacy,and related fields,underscoring its interdisciplinary impact.In this perspective,we present recent advances and challenges in the biomimetic synthesis of natural products,along with the significance and prospects of this field,highlighting the transformative potential of biomimetic synthesis strategies for both chemical and biosynthetic approaches to natural product synthesis in the pursuit of novel therapeutic agents. 展开更多
关键词 Natural products Natural product synthesis Biomimetic synthesis Biomimetic synthesis strategy
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Research on the Construction and Practice of an Evidence-Based Value-Added Evaluation System Based on Data-Driven 被引量:1
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作者 Lingduo Yang Lili Xu +2 位作者 Yan Xu Furong Peng Shuai Zhang 《Journal of Contemporary Educational Research》 2025年第5期61-67,共7页
Based on the educational evaluation reform,this study explores the construction of an evidence-based value-added evaluation system based on data-driven,aiming to solve the limitations of traditional evaluation methods... Based on the educational evaluation reform,this study explores the construction of an evidence-based value-added evaluation system based on data-driven,aiming to solve the limitations of traditional evaluation methods.The research adopts the method of combining theoretical analysis and practical application,and designs the evidence-based value-added evaluation framework,which includes the core elements of a multi-source heterogeneous data acquisition and processing system,a value-added evaluation agent based on a large model,and an evaluation implementation and application mechanism.Through empirical research verification,the evaluation system has remarkable effects in improving learning participation,promoting ability development,and supporting teaching decision-making,and provides a theoretical reference and practical path for educational evaluation reform in the new era.The research shows that the evidence-based value-added evaluation system based on data-driven can reflect students’actual progress more fairly and objectively by accurately measuring the difference in starting point and development range of students,and provide strong support for the realization of high-quality education development. 展开更多
关键词 DATA-DRIVEN evidence-based evaluation Value-added evaluation Large model Educational evaluation reform
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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol 被引量:2
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作者 Peng Zhu Cun Liu +5 位作者 Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong Liu Guohui Yang 《Journal of Energy Chemistry》 2025年第1期458-468,共11页
Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive st... Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented growth.The obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis. 展开更多
关键词 MFI zeolite ZSM-5 NANOSHEETS Scale-up synthesis Aromatic alkylation
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