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古生物学报 2001年第4期40卷 471-485页

作者：梅仕龙 charles m. Henderson 中国地质大学北京100083 University of Calgary CalgaryAlberta

阐述二叠纪 6个时期牙形石的分布及其古地理分区的划分和演变 ,探讨牙形石古地理分区的主控因素及其与古气候演变的关系。

关键词：二叠纪牙形石古地理分区古气候科迪勒拉山脉有关地体泛大陆演化控制因素

Spatiotemporal continuum generation in polariton waveguides

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Light(Science & Applications) 2019年第1期8卷 1117-1127页

作者： Paul m.Walker charles E.Whittaker Dmitry V.Skryabin Emiliano Cancellieri Ben Royall maksym Sich Ian Farrer David A.Ritchie maurice S.Skolnick Dmitry N.Krizhanovskii Department of Physics and Astronomy University of SheffieldSheffield S37RHUK Department of Physics University of BathBath BA27AYUK ITmO University Kronverksky Avenue 49St.Petersburg 197101Russia Department of Physics Lancaster UniversityLancaster LA14YBUK Department of Electronic and Electrical Engineering University of SheffieldSheffield S37HQUK Cavendish Laboratory University of CambridgeCambridge CB30HEUK

We demonstrate the generation of a spatiotemporal optical continuum in a highly nonlinear exciton–polariton waveguide using extremely low excitation powers(2-ps,100-W peak power pulses)and a submillimeter device suitable for integrated optics *** observe contributions from several mechanisms over a range of powers and demonstrate that the strong light–matter coupling significantly modifies the physics involved in all of *** experimental data are well understood in combination with theoretical *** results are applicable to a wide range of systems with linear coupling between nonlinear oscillators and particularly to emerging polariton devices that incorporate materials,such as gallium nitride and transition metal dichalcogenide monolayers that exhibit large light–matter coupling at room *** open the door to low-power experimental studies of spatiotemporal nonlinear optics in submillimeter waveguide devices.

关键词： millimeter waveguide optics

Exercise Catheterization for Hemodynamic Evaluation of Adults with Coarctation of the Aorta

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Congenital Heart Disease 2022年第6期17卷 605-615页

作者： Irene martin de miguel C.charles Jain Alexander C.Egbe Jason H.Anderson Heidi m.Connolly William R.miranda Department of Cardiovascular medicine Mayo ClinicRochesterMinnesotaUSA Department of Pediatric and Adolescent medicine Division of Pediatric CardiologyMayo ClinicRochesterMinnesotaUSA

Background: Coarctation of the aorta (CoA) is associated with a generalized arteriopathy and long-term complicationsdespite repair. Data on invasive exercise hemodynamics in this population are lacking. Accordingly, wereviewed adults with CoA undergoing exercise catheterization to assess 1. hemodynamic profile;2. feasibilityfor assessment of CoA severity. methods: Twenty patients undergoing exercise cardiac catheterization (12 armadduction and 8 supine cycle ergometry) at a quaternary care center between 2004 and 2021 were identified. Restingand exercise hemodynamic data were abstracted from the procedure logs. Results: mean age was 43.6 ±12.0 years. Eleven patients (55%) had resting pulmonary arterial wedge pressure (PAWP) >15 mmHg;amongthose undergoing arterial catheterization, left ventricular end-diastolic pressure was >15 mmHg in 63%. Elevenpatients (55%) had pulmonary hypertension: 7 (35%) combined and 4 (20%) isolated post-capillary. At peak exercise,ΔPAWP/Δcardiac output (CO) ≥2 and Δmean pulmonary artery pressure/ΔCO ≥3 mmHg/l/min were foundin 7 (78%) and 6 (67%) patients, respectively;the composite of exercise PAWP ≥25 mmHg or ΔPAWP/ΔCO>2 was seen in 12 (86%). CoA peak-to-peak gradients at baseline (n = 14) and during exercise (n = 9) were 12(3–16) and 16 mmHg (9–28), respectively. Only 2 patients had an increase in CoA gradient to >20 mmHg withexercise. Conclusions: Diastolic dysfunction and pulmonary hypertension were highly prevalent, with exerciseunmasking abnormal diastolic and pulmonary vascular reserve in some individuals. most patients failed to showsignificant increases in CoA peak-to-peak gradients with exercise. Further studies are warranted to establish thebest diagnostic method for CoA severity assessment.

关键词： Coarctation of the aorta exercise heart catheterization diastolic dysfunction hypertension

Effects of Land Use on the Riparian Vegetation along the Njoro and Kamweti Rivers, Kenya

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Open Journal of Ecology 2021年第11期11卷 807-827页

作者： Judith C. Koskey charles m. m’Erimba George m. Ogendi Department of Environmental Science Egerton University Egerton Kenya Department of Biological Sciences Egerton University Egerton Kenya Dryland Research Training and Ecotourism Centre Chemeron Egerton University Egerton Kenya

Riparian zones are valuable ecosystems. They act as the ecological engineers that improve river health by delivering a range of ecosystem functions. They play a significant role in river health and provide various ecosystem goods and services for human well-being. Currently, riparian areas are under threat due to intensive human activities such as agriculture and urbanization, which alter riparian ecosystem structure and composition. The main objective of this study was to determine the effect of adjacent land use on the structure and diversity of the riparian vegetation in the Njoro and Kamweti Rivers. Along each river, three sampling sites were selected within the major land use categories which were;forest, agricultural and built-up areas. At each site, three 70 m long transects were established perpendicular to the river. The three plots were systematically established, separated by a 5 m distance along each transect. Forest canopy cover was estimated in percentage. Njoro River riparian vegetation recorded a total of 145 plant species from 40 families where trees and shrubs were dominant in the forest area, and herbs dominated the agricultural and built-up areas. In Kamweti River riparian area, a total of 110 species from 45 families were encountered, in which trees dominated the forest area. A similar trend to the Njoro River was observed, in which herbs were dominant in the agricultural and built-up areas. In Njoro River, the Shannon diversity (H’) values ranged between 2.73 and 3.08 whereas Kamweti River riparian area values ranged from 2.59 to 3.40. At the level of P ≤ 0.05, T-Test revealed that there was no significant difference in plant abundance and diversity between the two rivers, with F = 0.53;P = 0.51 and F = 2.71;P = 0.17. Human-centered disturbances along the Njoro and Kamweti River riparian areas have affected the riparian vegetation as shown by the decrease in plant species diversities, and the change in vegetation composition and distribution ac

关键词： Land Use Riparian Vegetation Composition Distribution Diversity

The Immersed Boundary method for Two-Dimensional Foam with Topological Changes

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Communications in Computational Physics 2012年第7期12卷 479-493页

作者： Yongsam Kim Yunchang Seol ming-Chih Lai charles S.Peskin Department of mathematics Chung-Ang UniversityDongjakgu HeukseokdongSeoul 156-756Korea Department of Applied mathematics Center of Mathematical Modeling and Scientific ComputingNational Chiao Tung University1001Ta Hsueh RoadHsinchu 300Taiwan Courant Institute of mathematical Sciences New York University251 Mercer StreetNew YorkNY 10012 USA

We extend the immersed boundary(IB)method to simulate the dynamics of a 2D dry foam by including the topological changes of the bubble *** the article[***,m.-***,and ***,***.229:5194-5207,2010],we implemented an IB method for the foam problem in the two-dimensional case,and tested it by verifying the von Neumann relation which governs the coarsening of a two-dimensional dry ***,the method implemented in that article had an important limitation;we did not allow for the resolution of quadruple or higher order junctions into triple junctions.A total shrinkage of a bubble with more than four edges generates a quadruple or higher order *** reality,a higher order junction is unstable and resolves itself into triple *** here extend the methodology previously introduced by allowing topological changes,and we illustrate the significance of such topological changes by comparing the behaviors of foams in which topological changes are allowed to those in which they are not.

关键词： Foam permeability capillary-driven motion immersed boundary method coarsening topological changes T1 and T2 processes

Simultaneous determination of 3-chlorotyrosine and 3-nitrotyrosine in human plasma by direct analysis in real time–tandem mass spectrometry

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Acta Pharmaceutica Sinica B 2015年第5期5卷 482-486页

作者： Yuqiao Song Jie Liao Cheng Zha Bin Wang charles C.Liu medical Experiment and Analysis Center of PLA General Hospital ASPEC Technologies Limited Beijing

A novel method for the simultaneous determination of 3-nitrotyrosine(NT) and 3-chlorotyrosine(CT) in human plasma has been developed based on direct analysis in real time–tandem mass spectrometry(DART–mS/mS). Analysis was performed in the positive ionization mode using multiple reaction monitoring(mRm) of the ion transitions at m/z 216.2/170.1 for CT, m/z 227.2/181.1 for NT and m/z 230.2/184.2 for the internal standard, d^3-NT. The assay was linear in the ranges 0.5–100 μg/m L for CT and 4–100 μg/m L for NT with corresponding limits of detection of 0.2 and 2 μg/m L. Intra- and inter-day precisions and accuracies were respectively matrix effects were also evaluated. The method is potentially useful for high throughput analysis although sensitivity needs to be improved before it can be applied in clinical research.

关键词： 3-Nitrotyrosine 3-Chlorotyrosine Determintion DART–mS/mS Human plasma

The secondary injury cascade after spinal cord injury:an analysis of local cytokine/chemokine regulation

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Neural Regeneration Research 2024年第6期19卷 1308-1317页

作者： Daniel J.Hellenbrand charles m.Quinn Zachariah J.Piper Ryan T.Elder Raveena R.mishra Taylor L.marti Phoebe m.Omuro Rylie m.Roddick Jae Sung Lee William L.murphy Amgad S.Hanna Department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public HealthMadisonWIUSA Department of Biomedical Engineering University of Wisconsin-MadisonMadisonWIUSA Department of Orthopedics and Rehabilitation University of Wisconsin-MadisonMadisonWIUSA Department of materials Science and Engineering University of Wisconsin-MadisonMadisonWIUSA Forward BIO Institute University of Wisconsin-MadisonMadisonWIUSA

After spinal cord injury,there is an extensive infiltration of immune cells,which exacerbates the injury and leads to further neural ***,a major aim of current research involves targeting the immune response as a treatment for spinal cord *** much research has been performed analyzing the complex inflammatory process following spinal cord injury,there remain major discrepancies within previous literature regarding the timeline of local cytokine *** objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury,identify sexual dimorphisms in terms of cytokine levels,and determine local cytokines that significantly change based on the severity of spinal cord *** were inflicted with either a mild contusion,moderate contusion,severe contusion,or complete transection,7 mm of spinal cord centered on the injury was harvested at varying times post-injury,and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex *** demonstrated pro-inflammatory cytokines including tumor necrosis factorα,interleukin-1β,and interleukin-6 were all upregulated after spinal cord injury,but returned to uninjured levels within approximately 24 hours post-injury,while chemokines including monocyte chemoattractant protein-1 remained upregulated for days *** contrast,several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days *** spinal cord injury,tissue inhibitor of metalloproteinase-1,which specifically affects astrocytes involved in glial scar development,increased more than all other cytokines tested,reaching 26.9-fold higher than uninjured *** a mild injury,11 cytokines demonstrated sexual dimorphisms;however,after a severe contusion only leptin levels were different between female and male *** conclusion,pro-inflammatory cytokines in

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord injury

Percutaneous ablation for HCC eligible to transplantation: providing more opportunities of remission in the context of graft shortage

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Hepatobiliary Surgery and Nutrition 2018年第4期7卷 302-304页

作者： Jean-charles Nault Pierre Nahon Olivier Séror Liver Unit Hopital Jean VerdierHopitaux Universitaires Paris-Seine-Saint-DenisAssistance-Publique Hopitaux de ParisBondyFrance Unitéde Formation et de Recherche Santémédecine et Biologie Humaine UniversitéParis 13Communautéd’Universités et Etablissements Sorbonne Paris CitéParisFrance Unitémixte de Recherche 1162 Génomique Fonctionnelle des Tumeurs SolidesInstitut National de la Santéet de la Recherche MédicaleParisFrance Department of Radiology Hopital Jean VerdierHopitaux Universitaires Paris-Seine-Saint-DenisAssistance-Publique Hopitaux de ParisBondyFrance

Liver transplantation(LT)is still considered as the best treatment for small HCC as compared to other curative therapeutic options such as resection and ablation,at least in *** Lee et al.(1)reported an excellent 10 years intention to treat overall survival in patients with HCC within milan criteria after first line radiofrequency ablation followed by LT and challenged the alarming study of Llovet et al.

关键词： al. Liver curative

Transplantation of stem cell-derived astrocytes for the treatment of amyotrophic lateral sclerosis and spinal cord injury

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World Journal of Stem Cells 2015年第2期7卷 380-398页

作者： charles Nicaise Dinko mitrecic Aditi Falnikar Angelo C Lepore Laboratory Neurodegeneration and Regeneration URPhy M-NARILISFaculty of MedicineUniversity of Namur Laboratory for Stem Cells Croatian Institute for Brain ResearchUniversity of Zagreb Department of Neuroscience Farber Institute for NeurosciencesSidney Kimmel Medical College at Thomas Jefferson University Medical College

Neglected for years, astrocytes are now recognized to fulfill and support many, if not all, homeostatic functionsof the healthy central nervous system(CNS). During neurodegenerative diseases such as amyotrophic lateral sclerosis(ALS) and spinal cord injury(SCI), astrocytes in the vicinity of degenerating areas undergo both morphological and functional changes that might compromise their intrinsic properties. Evidence from human and animal studies show that deficient astrocyte functions or loss-of-astrocytes largely contribute to increased susceptibility to cell death for neurons, oligodendrocytes and axons during ALS and SCI disease progression. Despite exciting advances in experimental CNS repair, most of current approaches that are translated into clinical trials focus on the replacement or support of spinal neurons through stem cell transplantation, while none focus on the specific replacement of astroglial populations. Knowing the important functions carried out by astrocytes in the CNS, astrocyte replacement-based therapies might be a promising approach to alleviate overall astrocyte dysfunction, deliver neurotrophic support to degenerating spinal tissue and stimulate endogenous CNS repair abilities. Enclosed in this review, we gathered experimental evidence that argue in favor of astrocyte transplantation during ALS and SCI. Based on their intrinsic properties and according to the cell type transplanted, astrocyte precursors or stem cell-derived astrocytes promote axonal growth, support mechanisms and cells involved in myelination, are able to modulate the host immune response, deliver neurotrophic factors and provide protective molecules against oxidative or excitotoxic insults, amongst many possible benefits. Embryonic or adult stem cells can even be genetically engineered in order to deliver missing gene products and therefore maximize the chance of neuroprotection and functional recovery. However, before broad clinical translation, further preclinical data

关键词： Neuroprotection Stem cell Cell therapy Astrocyte Transplantation Amyotrophic lateral sclerosis Spinal cord injury

Pyrolytic synthesis of graphene-encapsulated zero-valent iron nanoparticles supported on biochar for heavy metal removal

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Biochar 2022年第1期4卷 25-41页

作者： Tharindu N.Karunaratne RmOshani Nayanathara Chanaka m.Navarathna Prashan m.Rodrigo Rooban V.K.G.Thirumalai charles U.Pittman Jr Yunsang Kim Todd mlsna Jilei Zhang Xuefeng Zhang Department of Sustainable Bioproducts Mississippi State UniversityMis-sissippi StateMS 39762USA. Department of Chemistry Mississippi State UniversityMississippi StateMS 39762USA. Institute for Imaging&Analytical Technologies Mississippi State UniversityMississippi StateMS 39762USA

Biochar(BC)-supported graphene-encapsulated zero-valent iron nanoparticle composites(BC-G@Fe0)are promising engineering nanocomposites that can be used to scavenge heavy metal from ***,the produc-tion of BC-G@Fe0 through carbothermal reduction using biomass as a carbon source remains challenging because of biomass pyrolysis ***,we examined two carbothermal reduction routes for preparing BC-G@Fe0 using bamboo as the carbon *** first route impregnated Fe ions(Fe^(2+)/^(3+))into unpyrolyzed bamboo parti-cles initially,followed by carbonization at 600-1000℃.This process produced BC-G@Fe0 dominated by iron carbide(Fe_(3)C),which led to low heavy metal removal efficiency(i.e.,Cu^(2+)capacity ofmmol g^(−1)).In the second route,bamboo particles were pyrolyzed(600℃)to biochar first,followed by impregnating this biochar with Fe ions,and then carbonized at 600-1000℃.This route produces zero-valent iron nanoparticles,which resulted in high heavy metal removal capacities(i.e.,0.30,1.58,and 1.91 mmol g^(−1)for Pb^(2+),Cu^(2+),and Ag+,respectively).The effects of car-bonization temperature(600-1000℃),iron source(i.e.,iron nitrates,iron sulfate,ferrous chloride,and ferric chloride),and iron loading(5-40%)on the morphology,structure,and heavy metal ion aqueous uptake performance of BC-G@Fe0 were also *** study revealed the formation mechanisms of BC-G@Fe0 through biomass carbother-mal reduction,which could guide the application-oriented design of multifunctional iron-BC composites for water remediation.

关键词： Bamboo Biochar Carbothermal reduction Fe3C metallic iron Heavy metal