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Tracking the Cretaceous transcontinental Ceduna River through Australia:The hafnium isotope record of detrital zircons from offshore southern Australia

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Geoscience Frontiers 2016年第2期7卷 237-244页

作者： jarred Lloyd Alan S.Collins justin L.Payne Stijn Glorie Simon Holford Anthony j.Reid Centre for Tectonics Resources and Exploration(TRaX)Department of Earth SciencesThe University of Adelaide Centre for Tectonics Resources and Exploration(TRaX)School of Built and Natural EnvironmentsThe University of South Australia Centre for Tectonics Resources and Exploration(TRaX)Australian School of PetroleumThe University of Adelaide Geological Survey of South Australia Department of State DevelopmentGovernment of South Australia

The middle-upper Cretaceous Ceduna River system traversed continental Australia from the NE coast to the centre of the southern coast. At its mouth, it formed a vast delta system that is similar in scale to the Niger delta of West Africa. The delta system is composed of two main lobes that represent different phases of delta construction. A recent hypothesis has challenged the traditional idea that both lobes of the delta were derived from a transcontinental river system by suggesting that the upper lobe （Santonian -Maastrichtian） is instead derived from a restricted catchment within southern Australia. Hf isotopic data presented here fingerprint the original source of the upper delta lobe zircons to NE Australia, with data comparing well with similar U-Pb and Lu-Hf isotopic data from the Lachlan Orogen, the New England Orogen, the eastern Musgraves Province and the northern Flinders Ranges. These data do not preclude a model where the lobe is derived from recycled Eromanga Basin sediments during a phase of late Cretaceous inland Australian uplift, but when coupled with reconnaissance low-temperature thermochronometry from the region of the Ceduna River course indicating widespread Triassic-jurassic exhumation, and comparisons with detrital zircon data from the Winton Formation upstream of any proposed uplift, we suggest that both lobes of the Ceduna Delta are likely to be derived from a transcontinental Ceduna River.

关键词： Detrital zircon Hf U-Pb Ceduna sub-basin Bight basin Australia

Magmatism and metamorphism at ca. 1.45 Ga in the northern Gawler Craton: The Australian record of rifting within Nuna(Columbia)

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Geoscience Frontiers 2019年第1期10卷 175-194页

作者： Laura j.Morrissey Karin M.Barovich Martin Hand Katherine E.Howard justin L.Payne School of Natural and Built Environments University of South Australia Department of Earth Sciences School of Physical Sciences University of Adelaide

U-Pb monazite and zircon geochronology and calculated metamorphic phase diagrams from drill holes in the northern Gawler Craton, southern Australia, reveal the presence of ca. 1.45 Ga magmatism and metamorphism. Magmatism and granulite facies metamorphism of this age has not previously been recognised in the Gawler Craton. The magmatic rocks have steep LREE-enriched patterns and high Ga/Al values, suggesting they are A-type granites. Calculated metamorphic forward models suggest that this event was associated with high apparent thermal gradients and reached pressures of 3.2 -5.4 kbar and temperatures of 775-815℃. The high apparent thermal gradients may reflect pluton-enhanced metamorphism, consistent with the presence of A-type granites. The recognition of ca. 1.45 Ga tectonism in the northern Gawler Craton is added to a compilation of ca. 1.50 -1.40 Ga magmatism, shear zone reactivation, rift basin development and isotope resetting throughout the South and North Australian Cratons that shows that this event was widespread in eastern Proterozoic Australia. This event is stylistically similar to ca. 1.45 Ga A-type magmatism and high thermal gradient metamorphism in Laurentia in this interval and provides further support for a connection between Australia and Laurentia during the Mesoproterozoic. The tectonic setting of the 1.50-1.40 Ga event is unclear but may record rifting within the Nuna(or Columbia) supercontinent, or a period of intracontinental extension within a long-lived convergent setting.

关键词： Gawler Craton Laurentia Metamorphism U-Pb geochronology Paleogeographic reconstruction

Effect of prophylactic clip placement following endoscopic mucosal resection of large colorectal lesions on delayed polypectomy bleeding: A meta-analysis

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World journal of Gastroenterology 2019年第18期25卷 2251-2263页

作者： Fares Ayoub Donevan R Westerveld justin j Forde Christopher E Forsmark Peter V Draganov Dennis Yang Department of Medicine University of Florida Division of Gastroenterology Hepatology and Nutrition University of Florida

BACKGROUND The role of prophylactic clipping for the prevention of delayed polypectomy bleeding(DPB) remains unclear and conclusions from prior meta-analyses are limited due to the inclusion of variety of resection techniques and polyp *** To conduct a meta-analysis on the effect of clipping on DPB following endoscopic mucosal resection(EMR) of colorectal lesions ≥ 20 *** We performed a search of PubMed and the Cochrane library for studies comparing the effect of clipping vs no clipping on DPB following endoscopic resection. The Cochran Q test and I^2 were used to test for heterogeneity. Pooling was conducted using a random-effects *** Thirteen studies with a total of 7794 polyps were identified, of which data was available on 1701 cases of EMR of lesions ≥ 20 mm. Prophylactic clipping was associated with a lower rate of DPB(1.4%) when compared to no clipping(5.2%)(pooled OR: 0.24, 95%CI: 0.12-0.50, P < 0.001) following EMR of lesions ≥ 20 *** was no significant heterogeneity among the studies(I^2 = 0%, P = 0.67).CONLUSION Prophylactic clipping may reduce DPB following EMR of large colorectal *** trials are needed to further identify risk factors and stratify high risk cases in order to implement a cost-effective preventive strategy.

关键词： Meta-analysis Clipping Endoscopic resection Endoscopic mucosal resection

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烯烃的选择性电化学氧化:研究进展与前景

Chinese journal of Catalysis 2023年第10期53卷 34-51页

作者：汪晋萧祖耀徐梽川任肖北京大学化学与分子工程学院北京100871 新加坡南洋理工大学材料科学与工程学院新加坡新加坡南洋理工大学先进催化科学与技术中心新加坡

烯烃类化合物,如乙烯和丙烯,是工业生产的关键原料,它们可以通过选择性氧化转化为环氧乙烷(EO)和环氧丙烷(PO)等高附加值的化学品.目前,烯烃类化合物转化主要通过热化学途径实现,通常需要高温高压条件,并可能导致过度氧化生成CO_(2),因... 详细信息

烯烃类化合物,如乙烯和丙烯,是工业生产的关键原料,它们可以通过选择性氧化转化为环氧乙烷(EO)和环氧丙烷(PO)等高附加值的化学品.目前,烯烃类化合物转化主要通过热化学途径实现,通常需要高温高压条件,并可能导致过度氧化生成CO_(2),因而选择性较低,且对经济和环境效益不友好.与此相对,电催化反应以电能作为驱动力,通过优化催化剂、电解液和反应电位等,有望在相对温和的条件下提高反应的选择性和能量效率,为高选择性烯烃氧化提供一种潜在策略.然而,当前烯烃的电化学选择性氧化的电流密度较低,整体生产成本相对较高,因此,有必要进一步研发高效且稳定的电化学选择性氧化烯烃的体系.本文综述了近期关于烯烃选择性电化学氧化的研究进展,研究主要集中在两个方面:一是烯烃在电极和电解液界面上直接进行电化学氧化的方法;二是通过电化学反应原位生成氧化剂(如Cl2和H_(2)O_(2))后,再对烯烃进行氧化的间接方法.对于烯烃的直接电化学氧化,反应的选择性可以通过调控几何效应和电子效应来优化.具体来说,通过引入如氯离子这样的物种,减少催化剂表面的可用活性位点数量,从而降低烯烃在催化剂表面的双位吸附,进一步降低过度氧化的可能性.此外,通过调整电催化剂的电子结构,改变其表面氧物种的电子性质,直接影响烯烃的加氧步骤,从而实现对反应选择性的精准调控.烯烃的氧化过程受限于其固有的缓慢反应动力学,导致直接电氧化所能实现的电流密度有限.为了提高该过程的速率,可以引入氧化还原介导物种来实现烯烃的选择性氧化.近期研究结果表明,卤素和过氧化氢作为介导物种在烯烃的选择性氧化反应中表现较好.利用先进的串联反应器技术,过氧化氢介导乙烯氧化为乙二醇的电流密度已经可以达到500m A cm^(–2).深入探索了烯烃电化学氧化的前沿研究方向.在烯烃的直接电氧化过程中,电催化剂的选择和性质对整体反应性能具有决定性影响.现有催化剂的化学成分、晶体学结构及合成方法上仍有较大的优化空间.尤为重要的是,关于烯烃电氧化的中间产物和反应途径,仍存在诸多争议.通过结合原位或在线的表征技术与密度泛函理论计算相结合,对反应机理进行深入探讨,将为反应体系的进一步完善提供理论支持.在间接氧化策略方面,反应器的设计与优化是研究的核心,旨在提升整体反应效率并确保经济效益.最后,进行技术经济分析为确定烯烃电氧化在特定条件下的经济效益提供有力依据.

关键词：烯烃氧化电催化过度氧化电子结构间接氧化

Update of transmission modelling and projections of gambiense human African trypanosomiasis in the Mandoul focus, Chad

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Infectious Diseases of Poverty 2022年第1期11卷 34-46页

作者： Kat S.Rock Ching-I Huang Ronald E.Crump Paul R.Bessell Paul E.Brown Inaki Tirados Philippe Solano Marina Antillon Albert Picado Severin Mbainda justin Darnas Emily H.Crowley Steve j.Torr Mallaye Peka Mathematics Institute University of WarwickAcademic Loop RoadCoventryCV47ALUK Zeeman Institute for Systems Biology&Infectious Disease Epidemiology Research(SBIDER) University of WarwickAcademic Loop RoadCoventryCV47ALUK Independent Consultant EdinburghUK Department of Vector Biology Liverpool School of Tropical MedicineLiverpoolUK Institut de Recherche pour le Développement UMR INTERTRYP IRD-CIRADUniversitéde Montpellier34398MontpellierFrance Swiss Tropical and Public Health Institute BaselSwitzerland University of Basel BaselSwitzerland Foundation for Innovative New Diagnostics(FIND) GenevaSwitzerland Programme National de Lutte contre la Trypanosomiase Humaine Africaine(PNLTHA) MoundouChad

Background:In recent years,a programme of vector control,screening and treatment of gambiense human African trypanosomiasis(gHAT)infections led to a rapid decline in cases in the Mandoul focus of *** represent the biology of transmission between humans and tsetse,we previously developed a mechanistic transmission model,fitted to data between 2000 and 2013 which suggested that transmission was interrupted by *** present study outlines refinements to the model to:(1)Assess whether elimination of transmission has already been achieved despite low-level case reporting;(2)quantify the role of intensified interventions in transmission reduction;and(3)predict the trajectory of gHAT in Mandoul for the next decade under different ***:Our previous gHAT transmission model for Mandoul was updated using human case data(2000-2019)and a series of model *** include how diagnostic specificity is incorporated into the model and improvements to the fitting method(increased variance in observed case reporting and how underreporting and improvements to passive screening are captured).A side-by-side comparison of fitting to case data was performed between the ***:We estimated that passive detection rates have increased due to improvements in diagnostic availability in fixed health facilities since 2015,by 2.1-fold for stage 1 detection,and 1.5-fold for stage *** find that whilst the diagnostic algorithm for active screening is estimated to be highly specific(95%credible interval(CI):99.9-100%,Specificity=99.9%),the high screening and low infection levels mean that some recently reported cases with no parasitological confirmation might be false *** also find that the focus-wide tsetse reduction estimated through model fitting(95%CI:96.1-99.6%,Reduction=99.1%)is comparable to the reduction previously measured by the decline in tsetse catches from monitoring *** line with previous results,the model suggests that transmission was

关键词： Gambiense human African trypanosomiasis (gHAT) Modelling Elimination of transmission Validation Tsetse Vector control Glossina Diagnostics

Engineered neuronal microtissue provides exogenous axons for delayed nerve fusion and rapid neuromuscular recovery in rats

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Bioactive Materials 2022年第12期7卷 339-353页

作者： justin C.Burrell Suradip Das Franco A.Laimo Kritika S.Katiyar Kevin D.Browne Robert B.Shultz Vishal j.Tien Phuong T.Vu Dmitriy Petrov Zarina SAli joseph M.Rosen D.Kacy Cullen Center for Brain Injury&Repair Department of NeurosurgeryPerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Department of Bioengineering School of Engineering&Applied ScienceUniversity of PennsylvaniaPhiladelphiaPAUSA Center for Neurotrauma Neurodegeneration&RestorationCorporal Michael J.Crescenz Veterans Affairs Medical CenterPhiladelphiaPA19104USA Axonova Medical LLCPhiladelphiaPAUSA Dartmouth-Hitchcock Medical Center Division of Plastic SurgeryDartmouth CollegeLebanonNHUSA

Nerve injury requiring surgical repair often results in poor functional recovery due to the inability of host axons to re-grow long distances and reform meaningful connections with the target muscle. While surgeons can re-route local axon fascicles to the target muscle, there are no technologies to provide an exogenous source of axons without sacrificing healthy nerves. Accordingly, we have developed tissue engineered neuromuscular interfaces (TE-NMIs) as the first injectable microtissue containing motor and sensory neurons in an anatomically-inspired architecture. TE-NMIs provide axon tracts that are intended to integrate with denervated distal structures and preserve regenerative capacity during prolonged periods without host innervation. Following implant, we found that TE-NMI axons promoted Schwann cell maintenance, integrated with distal muscle, and preserved an evoked muscle response out to 20-weeks post nerve transection in absence of innervation from host axons. By repopulating the distal sheath with exogenous axons, TE-NMIs also enabled putative delayed fusion with proximal host axons, a phenomenon previously not achievable in delayed repair scenarios due to distal axon degeneration. Here, we found immediate electrophysiological recovery after fusion with proximal host axons and improved axon maturation and muscle reinnervation at 24-weeks post-transection (4-weeks following delayed nerve fusion). These findings show that TE-NMIs provide the potential to improve functional recovery following delayed nerve repair.

关键词： Nerve regeneration Neuromuscular injury Muscle preservation Tissue engineering Microtissue Axon fusion

Taxonomic revision of genus Rohanixalus(Anura:Rhacophoridae)in China with description of one new species

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Zoological Research 2023年第6期44卷 1146-1151页

作者： Xiao-Long Liu jun-Kai Huang Bryan L.Stuart Ren-Da Ai justin M.Bernstein Chatmongkon Suwannapoom Siriwadee Chomdej jing Che Zhi-Yong Yuan Integrative Science Center of Germplasm Creation in Western China(Chongqing)Science City Biological Science Research CenterSouthwest UniversityChongqing 400715China Key Laboratory of Freshwater Fish Reproduction and Development(Ministry of Education) School of Life SciencesSouthwest UniversityChongqing 400715China Guangxi Key Laboratory of Rare and Endangered Animal Ecology Guangxi Normal UniversityGuilinGuangxi 541004China North Carolina Museum of Natural Sciences Raleigh NC 27601USA Key Laboratory for Conserving Wildlife with Small Populations in Yunnan Southwest Forestry UniversityKunmingYunnan 650224China Center for Genomics University of KansasLawrenceKansas 66044USA Division of Fishery School of Agriculture and Natural ResourcesUniversity of PhayaoPhayao 56000Thailand Department of Biology Faculty of ScienceChiang Mai UniversityChiang Mai 50200Thailand State Key Laboratory of Genetic Resources and Evolution Yunnan Key Laboratory of Biodiversity and Ecological Conservation of Gaoligong MountainKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar

DEAR EDITOR,Based upon morphological and molecular evidence,the authors revised the genus Rohanixalus Biju,Garg,Gokulakrishnan,Chandrakasan,Thammachoti,Ren,Gopika,Bisht,Hamidy and Shouche,2020(Anura:Rhacophoridae)in China through describing one new species,adding one species to the fauna(***)and supplementing data on one species(Rohanixalus hansenae;Supplementary Materials).

关键词： Anura species Taxonomic

Tyrosine aminotransferase: biochemical and structural properties and molecular dynamics simulations

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Protein & Cell 2010年第11期1卷 1023-1032页

作者： Prajwalini Mehere Qian Han justin A.Lemkul Christopher j.Vavricka Howard Robinson David R.Bevan jianyong Li Department of Biochemistry Virginia TechBlacksburgVA 24061USA CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Biology Department Brookhaven National LaboratoryUptonNY 11973USA

Tyrosine aminotransferase(TAT)catalyzes the transamination of tyrosine and other aromatic amino *** enzyme is thought to play a role in tyrosinemia type II,hepatitis and hepatic carcinoma *** objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these *** TAT(mTAT)was cloned from a mouse cDNA library,and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic *** recombinant mTAT is able to catalyze the transamination of tyrosine usingα-ketoglutaric acid as an amino group acceptor at neutral *** enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxyphenylpyruvate,phenylpyruvate and alpha-ketocaproic acid as amino group *** macromolecular crystallography we have determined the mTAT crystal structure at 2.9Å*** crystal structure revealed the interaction between the pyridoxal-5′-phosphate cofactor and the enzyme,as well as the formation of a disulphide *** detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing *** dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate *** biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

关键词： tyrosine aminotransferase crystal structure substrate specificity tyrosine tyrosinemia

Risk scoring model for prediction of non-home discharge after transcatheter aortic valve replacement

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journal of Geriatric Cardiology 2020年第10期17卷 621-627页

作者： Alexis K Okoh Ebru Ozturk justin Gold Emaad Siddiqui Nehal Dhaduk Bruce Haik Chun-Guang CHEN Marc Cohen Mark j Russo Cardiovascular Outcomes Research Institute RWJ Barnabas Health-NBIMCNewarkNew JerseyUSA Department of Medicine Division of BiostatisticsHacettepe UniversityAnkaraTurkey Rutgers New jersey Medical School NewarkNew JerseyUSA Department of Surgery Division of Cardiothoracic SurgeryRutgers Robert Wood Johnson Medical SchoolNew BrunswickNew JerseyUSA

Background Patients undergoing transcatheter aortic valve replacement(TAVR) are likely to be discharged to a location other than home. We aimed to determine the association between preoperative risk factors and non-home discharge after TAVR. Methods Patients discharged alive after TAVR at three centers were identified from a prospectively maintained database randomly divided into 80% derivation and 20% validation cohorts. Logistic regression models were fit to identify preoperative factors associated with non-home discharge in the derivation cohort. Multivariable models were developed and a nomogram based risk-scoring system was developed for use in preoperative counseling. Results Between june 2012 and December 2018, a total of 1,163 patients had TAVR at three centers. Thirty-seven patients who died before discharge were excluded. Of the remaining 1,126 patients(97%) who were discharged alive, the incidence of non-home discharge was 25.6%(n = 289). The patient population was randomly divided into the 80%(n = 900) derivation cohort and 20%(n = 226) validation cohort. Mean ± SD age of the study population was 83 ± 8 years. In multivariable analysis, factors that were significantly associated with non-home discharge were extreme age, female sex, higher STS scores, use of general anesthesia, elective procedures, chronic liver disease, non-transfemoral approach and postoperative complications. The unbiased estimate of the C-index was 0.81 and the model had excellent calibration. Conclusions One out of every four patients undergoing TAVR is discharged to a location other than home. Identification of preoperative factors associated with non-home discharge can assist patient counseling and postoperative disposition planning.

关键词： Aortic valve replacement Non-home discharge Postoperative risk Transcatheter Transfemoral