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Effects of serum proteins on corrosion rates and product bioabsorbability of biodegradable metals

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Regenerative Biomaterials 2024年第1期3卷 132-148页

作者： Hongjie Zhang Xin Li Zehua Qu Wanqian Zhang Qunsong Wang Dinglingge Cao Yaoben Wang Xin Wang Yang Wang Lin Yu Jiandong Ding State key laboratory of molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Corrodible metals are the newest kind of biodegradable materials and raise a new problem of the corrosion ***,the removal of the precipitated products has been unclear and even largely ignored in ***,we find that albumin,an abundant macromolecule in serum,enhances the solubility of corrosion products of iron in blood mimetic Hank’s solution *** is universal for other main biodegradable metals such as magnesium,zinc and polyester-coated *** also influences corrosion rates in diverse trends in Hank’s solution and normal *** on quantitative study theoretically and experimentally,both the effects on corrosion rates and soluble fractions are interpreted by a unified mechanism,and the key factor leading to different corrosion behaviors in corrosion media is the interference of albumin to the Ca/P passivation layer on the metal *** work has illustrated that the interactions between metals and media macromolecules should be taken into consideration in the design of the next-generation metal-based biodegradable medical devices in the formulism of precision *** improved Hank’s solution in the presence of albumin and with a higher content of initial calcium salt is suggested to access biodegradable metals potentially for cardiovascular medical devices,where the content of calcium salt is calculated after consideration of chelating of calcium ions by albumin,resulting in the physiological concentration of free calcium ions.

关键词： biodegradable metal macromolecule albumin corrosion bioabsorbability iron polylactide magnesium zinc

LociScan,a tool for screening genetic marker combinations for plant variety discrimination

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The Crop Journal 2024年第2期12卷 583-593页

作者： Yang Yang Hongli Tian Hongmei Yi Zi Shi Lu Wang Yaming Fan Fengge Wang Jiuran Zhao Beijing key laboratory of Maize DNA Fingerprinting and molecular Breeding Maize Research InstituteBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China

To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker *** describe a marker combination screening model based on the genetic algorithm(GA)and implemented in a software tool,Loci ***-based variety discrimination power provided the largest optimization space among multiple fitness *** GA parameters,an increase in population size and generation number enlarged optimization depth but also calculation *** algorithm afforded the same optimization depth as GA but vastly increased calculation *** comparison with two other software tools,Loci Scan accommodated missing data,reduced calculation time,and offered more fitness *** large datasets,the sample size of training data exerted the strongest influence on calculation time,whereas the marker size of training data showed no effect,and target marker number had limited effect on analysis speed.

关键词： plant variety discrimination Genetic marker combination Variety discrimination power Genetic algorithm

Invasion of fall armyworm led to the succession of maize pests in Southwest China

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Journal of Integrative Agriculture 2024年第4期23卷 1300-1314页

作者： Zezheng Fan Yifei Song Shengyuan Zhao Kongming Wu Agricultural Information institute Chinese Academy of Agricultural SciencesBeijing 100081China Guangdong laboratory for Lingnan Modern Agriculture Guangzhou 510642China State key laboratory for Biology of plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China

The invasive fall armyworm Spodoptera frugiperda(***)invaded Asia in 2018,colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and *** has resulted in widespread infestations,with significant impacts on maize production in various Asian *** studies have shown that the invasion of this pest can alter the species relationships of maize pests,but the actual impact on maize pest management is still *** study investigated the changes in maize pest occurrence and pesticide use in the annual breeding areas of *** in Yunnan Province and the Guangxi Zhuang Autonomous Region of China during 2017-2021,based on surveys and interviews with small farmers in maize *** results showed that *** has emerged as the dominant species among maize pests after invasion and colonization,replacing traditional pests such as Ostrinia furnacalis,Spodoptera litura,Agrotis ypsilon,and Rhopalosiphum *** variety of pesticides used for maize pest control has changed from chlorpyrifos,lambda-cyhalothrin,and acetamiprid to emamectin benzoate-based pesticides with high effectiveness against ***,the frequency of maize pest chemical applications has increased from an average of 5.88 to 7.21 times per season,with the amounts of pesticides used in summer and autumn maize being significantly higher than in winter and spring maize,thereby increasing application costs by more than 35%.The results of this study clarified the impact of *** invasion on maize pest community succession and chemical pesticide use in tropical and south subtropical China,thereby providing a baseline for modifying the regional control strategies for maize pests after the invasion of this relatively new pest.

关键词： Spodoptera frugiperda annual breeding region sweet waxy corn economic evaluation

Mechanisms of inclusion-induced pitting of stainless steels:A review

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Journal of Materials Science & Technology 2024年第1期168卷 143-156页

作者： Yangting Sun Xin Tan Rulei Lan Guoyong Ran Jin Li Yiming Jiang Department of Materials Science State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai 200438China

Pitting is a common type of localized corrosion in passive alloys that can cause rapid failure of material or *** the case of stainless steels,non-metallic inclusions have been identified as the most susceptible sites for pitting,and have therefore garnered significant *** review critically ex-amines the issue of how inclusions induce pitting,with a particular focus on three mechanisms:sponta-neous dissolution of inclusions,active dissolution of Cr-depleted regions,and propagation of microcracks at the inclusion-matrix *** researchers have made significant strides in understanding these mechanisms over the past few decades,many gaps and controversies *** such as the ini-tial driving force of inclusion dissolution and factors affecting Cr-depleted regions require further ***,some old concepts and methods need to be revised to arrive at more credible *** review aims to delve deeply into these important issues and provide inspiration for future research.

关键词： Pitting Inclusion Stainless steel Localized corrosion MnS

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

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Science China Chemistry 2024年第6期67卷 2002-2008页

作者： Qi Meng Tao Qin Huanran Miao Ge Zhang Qian Zhang Jilin Province key laboratory of Organic Functional molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State key laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-N bond forging through an S_(N)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-N bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

Engineering a high-barrier d-f single-molecule magnet centered with hexagonal bipyramidal Dy(Ⅲ)unit

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Science China Chemistry 2024年第10期67卷 3291-3298页

作者： Wei Deng Chan-Ying Yao Yan-Cong Chen Ying-Qian Zhou Shan-Nan Du Jun-Liang Liu Ming-Liang Tong key laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistryInstitute of Green Chemistry and Molecular EngineeringGuangdong Basic Research Center of Excellence for Functional Molecular EngineeringSun Yat-sen UniversityGuangzhou 510006China

In the pursuit of high-performance single-molecule magnets(SMMs),incorporating intramolecular magnetic coupling emerges as a pivotal *** these,d-f SMMs have garnered significant attention due to their remarkable versatility,which lies in their ability to tune coordination environments and facilely substitute metal ***,achieving performance-centric d-f SMMs through the synergistic interplay between highly anisotropic f ions and d-f magnetic interactions remains a formidable *** mononuclear hexagonal bipyramidal(D_(6h))Dy^(Ⅲ)SMMs have been successfully isolated,the exploration of d-f SMMs featuring D_(6h)-lanthanide metal centers remains uncharted *** this study,we employed planar bipodal ligands in conjunction with“staple-like”axial phenoxide ligands to synthesize the first hexagonal bipyramidal d-f ***,this compound exhibits alternating-current magnetic susceptibilities peaking up to 68 K with an energy barrier surpassing 1,200 K,thus establishing a new benchmark within the heterometallic d-f SMM landscape inclusive of complexes with diamagnetic d metals and paramagnetic f ***,the ferromagnetic interaction at the d-f sites engenders oscillating relaxation times contingent on the magnetic field—a characteristic distinct from mononuclear *** findings shed light on a deliberate design approach for d-f SMMs,emphasizing the cooperative utilization of high-barrier lanthanide modules alongside d ions through magnetic *** synergy significantly enhances and diversifies the magnetic dynamics of these intriguing molecular systems.

关键词： single-molecule magnets magnetic coupling crystal engineering hexagonal bipyramid energy barrier

Colorimetric Detection of Acid Phosphatase and Malathion Using NiCo_(2)O_(4)Nanosheets as Peroxidase-Mimicking Activity

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Journal of Analysis and Testing 2024年第2期8卷 170-179页

作者： Jia Chen Zerong Long Yan Li Hongdeng Qiu Xinjiang Uygur Autonomous Product Quality Supervision and Inspection institute Urumqi830000China CAS key laboratory of Chemistry of Northwestern plant Resources and key laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The establishment of a low-cost and facile approach for the assay of acid phosphatase(ACP)and its inhibitor is a research *** this paper,we successfully synthesized NiCo_(2)O_(4)nanosheets with peroxidase-mimicking activity in alkaline deep eutectic solvents(DESs)composed of NaOH and PEG-200,which can catalyze 3,3',5,5'-tetramethylbenzidine(TMB)to the oxidation state TMB(ox-TMB)in the presence of *** to L-ascorbic acid-2-phosphate can be hydrolyzed into ascorbic acid by ACP,the peroxidase-like activity of NiCo_(2)O_(4)nanosheets is ***,the addition of malathion,an inhibitor of ACP,can inhibit the activity of ACP and thus limit the production of ascorbic acid(AA).Therefore,a colorimetric approach can be established for highly sensitive and selective detection of ACP and malathion with detection limits of 0.032 U/L and 0.65 nmol/L,*** importantly,this method can be successfully applied to malathion detection in environmental samples tap water and food cucumber juice,indicating that it has potential application prospects in environmental and agricultural fields.

关键词： NiCo_(2)O_(4)nanosheets Acid phosphatase Malathion Peroxidase-mimicking activity Colorimetric

Axial enantiomers with donor-regulated TADF feature for multicolor circularly polarized electroluminescence

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Science China Chemistry 2024年第6期67卷 2039-2045页

作者： Chen-Hao Guo Wen-Long Zhao Ke-Ke Tan Wei-Chen Guo Liheng Feng Chuan-Feng Chen Meng Li School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan030006China Beijing National laboratory for molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral *** pairs of axial enantiomers with donor-regulated TADF feature,namely(R/S)-TPCBD,(R/S)-DPCBD,and(R/S)-DPACBD,were synthesized by introducing carbazole donors with different substituents onto biphenyl cyanide *** the electron-donating ability of donors increases,the emission of these axial enantiomers ranges from 455,476 to 552 nm,their singlet-triplet energy gaps(ΔE_(ST))gradually decrease from 0.30,0.22 to 0.02 e V,accompanied by an increasement in the transition rate(k_(RISC))of RISC process,and the k_(RISC)of DPACBD could reach up to 7.16×10^(5)s^(-1).These axial enantiomers also exhibit mirror-image CD and circularly polarized luminescence(CPL)***,OLEDs based on TPCBD,DPCBD,and DPACBD as emitter were then fabricated,which displayed blue,green,and orange electroluminescence with EQE_(max)of 13.0%,16.4%,and 25.0%,*** results also exhibited a phenomenon of device efficiency increasing with the enhancement of donor ***,the CP-OLEDs using(R/S)-TPCBD,(R/S)-DPCBD and(R/S)-DPACBD as emitters displayed intense CPEL signals with g_(EL)values of 3.4×10^(-3)/-4.1×10^(-3),3.2×10^(-3)/-3.1×10^(-3)and2.3×10^(-3)/-2.1×10^(-3),*** convenient molecular engineering of donor regulation in the same molecular skeleton,CP-TADF materials with multicolor CPEL and improved device performance could be conveniently achieved.

关键词： axial chirality thermally activated delayed fluorescence circularly polarized luminescence electroluminescence organic light-emitting diodes

Discovery of antitumor diterpenoids from Casearia graveolens targeting VEGFR-2 to inhibit angiogenesis

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Chinese Journal of Natural Medicines 2024年第9期22卷 842-853页

作者： WANG Sibei LIU Yuhui LIANG Yue XI Yaru ZHAI Yupeng LEE Dongho XU Jing GUO Yuanqiang State key laboratory of Medicinal Chemical Biology College of Pharmacyand Tianjin Key Laboratory of Molecular Drug ResearchNankai UniversityTianjin 300350China State key laboratory of Functions and Applications of Medicinal plants Guizhou Medical UniversityGuiyang 550014China Department of plant Biotechnology College of Life Sciences and BiotechnologyKorea UniversitySeoul 02841South Korea

Eight novel clerodane diterpenoids(1-8)were isolated from the twigs of Casearia *** structures were elucidated through comprehensive nuclear magnetic resonance(NMR),high-resolution electrospray ionization mass spectrometry(HRESI-MS),and electronic circular dichroism(ECD)*** addition to structural determination,surface plasmon resonance(SPR)assays were conducted to investigate molecular interactions,revealing that compound 8 exhibited high affinity for vascular endothelial growth factor receptor 2(VEGFR2),a key regulator of tumor *** in vivo experiments demonstrated that compound 8 effectively inhibited angiogenesis and displayed significant antitumor activity by suppressing tumor proliferation and metastasis in zebrafish xenograft *** findings suggest that compound 8 holds promise as an anticancer lead compound targeting VEGFR-2 to obstruct tumor angiogenesis.

关键词： Clerodane diterpenoids Casearia graveolens Surface plasmon resonance Vascular endothelial growth factor receptor 2 Antitumor activity Zebrafish