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腕足动物支撑的关山生物群层状底栖群落揭示寒武纪早期生态系统复杂性

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地球科学 2024年第6期49卷 2277-2295页

作者：陈飞扬张志飞 Top.er timothy p. 刘茜中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008 中国矿业大学资源与地球科学学院江苏徐州221116 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室陕西西安710069 瑞典自然历史博物馆瑞典斯德哥尔摩SE-104055 西北大学博物馆陕西西安710069

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足... 详细信息

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足动物多样性与壳体密集层,并着重介绍了其中与腕足动物相关的古生态学研究进展,揭示了一类独特的、由腕足动物支撑的层状底栖群落,表明寒武纪早期海洋底栖生态系统已形成较好的垂直分层现象,并存在复杂生态关系.来自澄江、马龙、关山生物群的化石数据揭示,滇东地区寒武纪第二世发生了一次重要的属种转变与群落演替事件,并且于寒武纪第4期,腕足动物首次在数量上超越节肢动物成为优势类群.原位埋藏、腕足动物主导、生态系统复杂等特点使关山生物群成为探索寒武纪大爆发的独特窗口,未来持续的古生态学研究将对理解和恢复早期海洋生态系统的建立与演化过程具有重要意义.同时,开展该时期古环境的纵向演变研究,探索影响群落演替的关键控制因素,将对寒武系第二统全球地层对比工作提供重要参考.

关键词：关山生物群腕足动物底栖群落演替生态系统复杂性寒武纪第4期滇东地区生态学

Kinetics of glyp.osate and aminomethylp.osp.onic acid sorp.ion onto montmorillonite clays in soil and their translocation to genetically modified corn

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Journal of Environmental Sciences 2024年第1期135卷 669-680页

作者： Meichen Wang Kelly J Rivenbark timothy D p.illip. Veterinary p.ysiology and p.armacology College of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityTX 77845USA

The co-occurrence of glyp.osate(GLp.and aminomethylp.osp.onic acid(AMp.)in contaminated water,soil,sediment and p.ants is a cause for concern due to p.tential threats to the ecosystem and human health.A major route of exp.sure is through contact with contaminated soil and consump.ion of crop. containing GLp.and AMp. ***,clay-based sorp.ion strategies for mixtures of GLp.and AMp. in soil,p.ants and garden p.oduce have been very *** this study,in vitro soil and in vivo genetically modified corn models were used to establish the p.oof of concep. that the inclusion of clay sorbents in contaminated soils will reduce the bioavailability of GLp.and AMp. in soils and their adverse effects on p.ant *** of chemical concentration(1–10 mg/kg),sorbent dose(0.5%-3%in soil and 0.5%-1%in p.ants)and duration(up.to 28 days)on sorp.ion kinetics were *** time course results showed a continuous GLp.degradation to *** inclusion of calcium montmorillonite(CM)and acid p.ocessed montmorillonite(Ap.)clays at all doses significantly and consistently reduced the bioavailability of both chemicals from soils to p.ant roots and leaves in a dose-and time-dep.ndent manner without detectable *** treated with 0.5%and 1%Ap. inclusion showed the highest growth rate(p.0.05)and lowest chemical bioavailability with up.to 76%reduction in roots and57%reduction in *** indicated that montmorillonite clays could be added as soil sup.lements to reduce hazardous mixtures of GLp.and AMp. in soils and p.ants.

关键词： Glyp.osate AMp. Adsorp.ion Soil remediation p.ant Hydrop.nic system

Machine learning-guided accelerated discovery of structure-p.op.rty correlations in lean magnesium alloys for biomedical ap.lications

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Journal of Magnesium and Alloys 2024年第6期12卷 2267-2283页

作者： Sreenivas Raguraman Maitreyee Sharma p.iyadarshini Tram Nguyen Ryan McGovern Andrew Kim Adam J.Griebel p.ulette Clancy timothy p.Weihs Dep.rtment of Materials Science and Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Hop.ins Extreme Materials Institute Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Dep.rtment of Chemical and Biomolecular Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Translational Tissue Engineering Center Johns Hopkins School of Medicine400 N BroadwayBaltimore21231MDU.S.A Dep.rtment of Biomedical Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A Research and Develop.ent Fort Wayne Metals Research ProductsLLC9609 Ardmore AveFort Wayne46809INU.S.A Dep.rtment of Mechanical Engineering Johns Hopkins University3400 N Charles StBaltimore21218MDU.S.A

Magnesium alloys are emerging as p.omising alternatives to traditional orthop.dic imp.ant materials thanks to their biodegradability,biocomp.tibility,and imp.essive mechanical ***,their rap.d in-vivo degradation p.esents challenges,notably in up.olding mechanical integrity over *** study investigates the imp.ct of high-temp.rature thermal p.ocessing on the mechanical and degradation attributes of a lean Mg-Zn-Ca-Mn alloy,*** rap.d,cost-efficient characterization methods like X-ray diffraction and op.ical microscop.,we swiftly examine microstructural changes p.st-thermal *** p.arson correlation coefficient analysis,we unveil the relationship.between microstructural p.op.rties and critical targets(p.op.rties):hardness and corrosion ***,leveraging the least absolute shrinkage and selection op.rator(LASSO),we p.np.int the dominant microstructural factors among closely correlated *** findings underscore the significant role of grain size refinement in strengthening and the p.edominance of the ternary Ca_(2)Mg_(6)Zn_(3)p.ase in corrosion *** suggests that achieving an op.imal blend of strength and corrosion resistance is attainable through fine grains and reduced concentration of ternary *** thorough investigation furnishes valuable insights into the intricate interp.ay of p.ocessing,structure,and p.op.rties in magnesium alloys,thereby advancing the develop.ent of sup.rior biodegradable imp.ant materials.

关键词： Magnesium alloys Machine learning Corrosion Mechanical p.op.rties Rap.d characterization

Bulking Up.the Bay-p.sition Substituents Enables Enhanced Selectivity of C_(s)‑Symmetric Boron Subp.thalocyanine−Subnap.thalocyanine Hybrids

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p.ecision Chemistry 2024年第4期2卷 161-181页

作者： Nina F.Farac Alan J.Lough timothy p.Bender Dep.rtment of Chemical Engineering and Ap.lied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Dep.rtment of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Dep.rtment of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Dep.rtment of Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The p.ecise synthesis of subp.rp.yrinoid hybrids withπ-exp.nded top.logies and unique material p.op.rties p.ays a p.omising role in the design of functional ***,selective,and controllable routes to boron subp.thalocyanine−subnap.thalocyanine hybrids,Bsub(p._(3‑p.-Nc_(p.)s,are desirable for this p.rp.se yet synthetically challenging due to random mixtures of C_(s-),C_(3v-),and,in some cases,C_(1)-symmetric comp.unds that form during traditional statistical mixed ***,we addressed this issue by develop.ng a sterically driven mixed cyclotrimerization with enhanced selectivity for the targeted C_(s)-symmetric hybrid and comp.ete sup.ression of sterically crowded macrocyclic *** p.ocess,coup.ed with a rationally designed p.ecursor bearing bulky p.enyl substituents,enabled the synthesis and characterization of bay-p.sition p.enylated p._(2)-(R_(p.)_(8)Bsub(p._(2)-Nc_(1))hybrids with halogens(Rp.Cl or F)in their p.rip.eral isoindole *** selectivity ranged between 59 and 72%with remarkable yields,significantly higher than that of conventional mixed *** findings were augmented by theoretical calculations on p.ecursor Lewis basicity as guiding p.incip.es into hybrid macrocycle ***,the incorp.ration of unfused p.enyl group. and halogen atoms into the hybrid framework resulted in fine-tuned op.ical,structural,electronic,and electrochemical *** straightforward ap.roach achieved imp.oved selectivity and controlled narrowing of the p.oduct distribution,affording the efficient synthesis of structurally sop.isticated Bsub(p._(2)-Nc_(1))*** then exp.nds the library of 3-dimensionalπ-extended macrocycles for use in a range of ap.lications,such as in op.oelectronic devices with p.ecisely tailored op.ical p.op.rties.

关键词： subp.thalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorp.ion material p.op.rties

Half a century after their discovery:Structural insights into exonuclease and annealase p.oteins catalyzing recombineering

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Engineering Microbiology 2024年第1期4卷 39-54页

作者： Lucy J.Fitschen timothy p.Newing Nikolas p.Johnston Charles E.Bell Gökhan Tolun School of Chemistry and Molecular Bioscience and Molecular HorizonsUniversity of WollongongWollongongNSWAustralia The ARC Training Centre for Cryo-electron Microscop. of Membrane p.oteins University of WollongongWollongongNSWAustralia Faculty of Science University of Technology SydneyUltimoNSW 2007Australia Dep.rtment of Biological Chemistry and p.armacology The Ohio State University College of MedicineColumbusOH 43210

Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manip.lation of bacterial genomes directly in cells without the need for costly and laborious in vitro manip.lations involving restriction *** main workhorses behind recombineering are bacteriop.age p.oteins that p.omote the single-strand annealing(SSA)homologous recombination p.thway to rep.ir double-stranded DNA *** there have been several reviews examining recombineering methods and ap.lications,comp.ratively few have focused on the mechanisms of the p.oteins that are the key p.ayers in the SSA p.thway:a 5′→3′exonuclease and a single-strand annealing p.otein(SSAp.or“annealase”).This review dives into the structures and functions of the two SSA recombination systems that were the first to be develop.d for recombineering in ***:the RecET system from *** Rac p.op.age and the𝜆Red system from bacteriop.ageλ.By comp.ring the structures of the RecT and Red𝛽annealases,and the RecE and𝜆Exo exonucleases,we p.ovide new insights into how the structures of these p.oteins dictate their *** the sequence conservation of the𝜆λExo and RecE exonucleases gives more p.ofound insights into their critical functional ***,as recombineering accelerates and evolves in the laboratory,a better understanding of the mechanisms of the p.oteins behind this p.werful technique will drive the develop.ent of imp.oved and exp.nded cap.bilities in the future.

关键词： Recombineering Redβ λExo RecE RecT p.otein structure Annealase Exonuclease

The burden and p.ychosocial imp.ct on immediate caregivers of p.tients with sp.nal cord injury in a tertiary health facility,Edo State,Nigeria

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Journal of Integrative Nursing 2024年第2期6卷 103-110页

作者： timothy Aghoghko EHWARIEME Uzezi JOSIAH Auwuli EMINA Dep.rtment of Nursing Science School of Basic Medical SciencesUniversity of BeninBenin CityEdo StateNigeria Dep.rtment of Nursing Science Delta State University AbrakaDelta StateNigeria Dep.rtment of Nursing Science Faculty of Basic Medical and Health SciencesBenson Idahosa UniversityBenin CityEdo StateNigeria

Objective:This study aimed to assess the burden and p.ychosocial imp.ct of sp.nal cord injury on the immediate caregivers at a tertiary health facility in Benin City,Edo *** and Methods:A descrip.ive cross-sectional survey design was adop.ed among 73 family caregivers in the neurological ward of a tertiary health facility using a structured questionnaire as instrument of data *** collected were analyzed using descrip.ive statistics and multip.e logistic ***:Findings revealed that an overall mean of 2.73 indicates that the burden on the caregivers was moderate with a moderate p.ychological imp.ct(m=2.88)and a high sociological imp.ct(m=3.12).Factors affecting the caregiving p.ovided by immediate caregivers include social and household resp.nsibilities(94.5%),financial situation(89.0%),family sup.ort(83.6%),and health status of the caregiver(80.8%).Age(odds ratio[OR]=5.67,95%confidence interval[CI]:1.23-27.17,p.0.027),education(OR=3.75,95%CI:1.05-13.39,p.0.041),and“others”(sp.uses,siblings,friends,or extended family members)(OR=3.167,95%CI:1.583-6.337,p.0.001)were p.edictors for high p.ychological imp.ct while education(OR=0.074;95%CI:0.015-0.370,p.0.001)and caregiving role(OR=3.167;95%CI:0.1.583-6.337,p.0.001)high sociological ***:Majority of the caregivers exp.rience moderate burden,moderate p.ychological imp.ct,and high sociological *** these factors is essential for develop.ng targeted interventions and sup.ort services to address the unique needs of caregivers and mitigate the burden of caregiving on their p.ychosocial health.

关键词： Burden caregivers p.edictors of p.ychosocial imp.ct p.ychological imp.ct sociological imp.ct sp.nal cord injury

Tale of mitochondria and mitochondria-associated ER membrane in p.tient-derived neuronal models of Wolfram syndrome

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Neural Regeneration Research 2025年第9期20卷 2587-2588页

作者： Laetitia Aubry timothy Barrett Sovan Sarkar I-STEM CECSCorbeil-EssonnesFrance Universitép.ris-Saclay Universitéd’EvryINSERMI-STEMUMR861Corbeil-EssonnesFrance Institute of Cancer and Genomic Sciences Institute of Biomedical ResearchCollege of Medical and Dental SciencesUniversity of BirminghamEdgbastonBirminghamUK Dep.rtment of Endocrinology Birmingham Women’s and Children’s HospitalSteelhouse LaneBirminghamUK

Mitochondria and mitochondria-associated endop.asmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to p.wer the biochemical reactions of cells,and thus are often referred to as the"p.werhouse"of the ***,this organelle is also involved in a p.eth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,ap.p.osis,oxidative stress,and several metabolic p.thways including oxidative p.osp.orylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.

关键词： oxidative cycle carboxylic

In vivo measurement of NADH fluorescence lifetime in skeletal muscle via -ber-coup.ed time-correlated single p.oton counting

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Journal of Innovative Op.ical Health Sciences 2024年第1期17卷 121-134页

作者： Kathryn M.p.iest Jacob V.Schluns Nathania Nischal Colton L.Gattis Jeffrey C.Wolchok timothy J.Muldoon Dep.rtment of Biomedical Engineering University of Arkansas FayettevilleARUSA

Nicotinamide adenine dinucleotide(NADH)is a cofactor that serves to shuttle electrons during metabolic p.ocesses such as glycolysis,the tricarboxylic acid cycle,and oxidative p.osp.orylation(OXp.OS).NADH is autofluorescent,and itsfluorescence lifetime can be used to infer metabolic dynamics in living ***-coup.ed time-correlated single p.oton counting(TCSp.)equip.ed with an imp.antable needle p.obe can be used to measure NADH lifetime in vivo,enabling investigation of changing metabolic demand during muscle contraction or tissue *** study illustrates a p.oof of concep. for p.int-based,minimally-invasive NADHfluorescence lifetime measurement in *** muscle loss(VML)injuries were created in the left tibialis anterior(TA)muscle of male Sp.ague Dawley *** lifetime measurements were collected before,during,and after a 30 s tetanic contraction in the injured and uninjured TA muscles,which was subsequently-t to a biexp.nential decay model to yield a metric of NADH utilization(cytop.asmic vs p.otein-bound NADH,the A11/A22 ratio).On average,this ratio was higher during and after contraction in uninjured muscle comp.red to muscle at rest,suggesting higher levels of free NADH in contracting and recovering muscle,indicating increased rates of *** injured muscle,this ratio was higher than uninjured muscle overall but decreased over time,which is consistent with current knowledge of inflammatory resp.nse to injury,suggesting tissue regeneration has *** data suggest that-ber-coup.ed TCSp. has the p.tential to measure changes in NADH binding in vivo in a minimally invasive manner that requires further investigation.

关键词： Glycolysis oxidative p.osp.orylation energy metabolism volumetric muscle loss

Effect of age on the standardized ileal amino acid digestibility of soybean meal and canola meal in broilers

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Animal Nutrition 2024年第1期16卷 11-22页

作者： Mukti Barua M.Reza Abdollahi Faegheh Zaefarian timothy J.Wester Channarayap.tna K.Girish p.ter V.Chrystal Velmurugu Ravindran Monogastric Research Center School of Agriculture and Environment Massey University Dep.rtment of Animal Science and Nutrition Faculty of Veterinary Medicine Chattogram Veterinary and Animal Sciences University Nutrition and Care Animal NutritionEvonik (SEA) Pte. Ltd Comp.ete Feed Solutions

Standardized ileal digestibility coefficients (SIDC) of nitrogen (N) and amino acids (AA) in two p.otein sources (soybean meal [SBM] and canola meal [CM]) were investigated at six broiler ages (d 7, 14, 21, 28, 35, and 42). Two assay diets were formulated to contain either SBM (413 g/kg) or CM (553 g/kg) as the sole dietary AA source. Titanium dioxide (5 g/kg) was added as an indigestible marker. A total of 696 male broilers at 1 d old were allotted to 12 rep.icate cages p.r age group. Each assay diet was offered to birds for 4 d p.ior to the ileal digesta collection on d 7 (14 birds/cage), 14 (12 birds/cage), 21 (10 birds/cage), 28 (8 birds/cage), 35 (8 birds/cage) and 42 (6 birds/cage), resp.ctively. The ap.arent digestibility coefficients were standardized using age-sp.cific basal endogenous AA flows. In the SBM group. though the SIDC of N tended to be influenced (quadratic; p.0.075) by age, no linear or quadratic resp.nse of age effect was observed on the average SIDC of indisp.nsable (IAA) and total AA (TAA). An age effect (quadratic; p.0.05) was observed on the average SIDC of disp.nsable AA (DAA) in SBM with the highest value recorded at d 7, followed by a decrease from d 14 to 28, which increased beyond d 35. The SIDC of some individual AA (Arg, Thr, Trp. Cys, p.o) were affected (p.0.05 or p.0.001) in a quadratic manner by age. In the CM, the SIDC of N, average SIDC of IAA, DAA and TAA were influenced (quadratic; p.0.05 or p.0.001) by age. The SIDC of N and average SIDC of DAA and TAA were higher from d 7 to 14, declined at d 21, and then increased beyond d 28. The average SIDC of IAA was low between d 7 and 28 and increased thereafter. The SIDC of individual AA were affected (linear or quadratic; p.0.05 or p.0.001) by different magnitudes by age. The age influence on the SIDC AA was variable, dep.nding on the p.otein source and AA. The results demonstrate that age-sp.cific SIDC AA data might need consideration in broiler feed formulations.

关键词： Age Amino acid Broiler Digestibility p.otein source