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Sulfur and carbon isotope records from 1700 to 800 Ma carbonates of the Jixian section,northern China:Implications for secular isotope variations in Proterozoic seawater and relationships to global supercontinental events

Sulfur and carbon isotope records from 1700 to 800 Ma carbon...

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中国科学院地质与地球物理研究所2007学术年会

作者： timothy w.lyons Department of Earth Sciences University of California Riverside.CA 92521USA

This study is a comprehensive,stable isotope survey of the marine carbonate-dominated,upper Paleo- to lower Neoproterozoic stratigraphy of Jixian County,***-associated sulfate(CAS) was extracted and measured forδS using the same samples analyzed forδ*** integrated proxy approach is a step towards a more comprehensive picture of secular variation in the composition of Proterozoic *** specifically sampled marine carbonate intervals from the lower section of the Chuanlinggou Formation,Changcheng Group(ca.1700 Ma) to the top of the Jingeryu Formation, Qingbaikou Group(ca.800 Ma).δC values are mostly negative in the upper Paleoproterozoic Changcheng Group,with an ascending trend from -3‰to 0‰.we observed variation of approximately 0±1‰in the Mesoproterozoic Jixian Group,and positive values of +2±2‰characterize the lower Neoproterozoic Qingbaikou *** variations inδS are more remarkable in their ranges and magnitudes,including conspicuously high values exceeding +30‰in the three intervals at ca.1700 Ma,1300-1100 Ma,and 1000-900 *** the Changcheng Group,δS values are typically higher than +25‰,with only a few values of less than +15‰.In contrast,most of the data spanning from the Mesoproterozoic Tieling Formation of the Jixian Group to the lower Neoproterozoic Jingeryu Formation of the Qingbaikou Group are highly variable between +10‰and +25‰,with some values exceeding +25‰. In the late Paleoproterozoic(1700-1600 Ma),a>10‰decrease inδS and～3‰increase inδC are coincident with,and likely related to,the breakup of Columbia,a supercontinent that predated *** and sulfur isotope data from the Mesoproterozoic,when global tectonic activity was comparatively weaker,fall mostly in the ranges of +15±10‰and 0±1‰,respectively,but fluctuations of>20‰forδS and>3‰for theδC at ca.1450-1400 Ma may reflect subduction and large-scale magmatic activity in island arcs marking the end of Columbia *** the late Mesoproterozoic (ca.1300-11

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A~60-Ma-long,high-resolution record of Ediacaran paleotemperature

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Science Bulletin 2022年第9期67卷 910-913,M0003页

作者： Biao Chang Chao Li Thomas J.Algeo timothy w.lyons wei Shi Meng Cheng Genming Luo Zhenbing She Shucheng Xie Jinnan Tong Maoyan Zhu Junhua Huang Ian Foster Aradhna Tripati State Key Laboratory of Biogeology and Environmental Geology School of Earth ScienceChina University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Department of Geology University of CincinnatiCincinnatiOH 45221-0013USA Department of Earth and Planetary Sciences University of CaliforniaRiversideCA 92521USA State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology&Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China UMR6538 Géosciences Océan Institut Universitaire Européen de la MerTechnopôle Brest-IroisePlouzané29280France Department of Earth Planetary and Space SciencesDepartment of Atmospheric and Oceanic SciencesInstitute of the Environment and SustainabilityUniversity of CaliforniaLos AngelesCA 90095USA

The Ediacaran Period(~635–539 Ma)was a critical time in Earth history due to large increases in atmospheric and oceanic oxygen levels and rapid evolution of early animals[1].It was also an interval of major climatic and geochemical perturbations,such as the~580-Ma Gaskiers Glaciation[2](Fig.S1 online)and the late Ediacaran Shuram Excursion(SE;also known as DOUNCE or EN3 in South China,see Fig.S2 online),which was the largest negative carbonate carbon isotope(δ13Ccarb)excursion in Earth history[3,4].In contrast to established redox,biological,and C-cycling records for the Ediacaran,however,no secular,high-resolution paleotemperature record with climatic significance has been reported to date,impeding our understanding of the relationships among major environmental,biological,geochemical,and climatic processes and milestones.

关键词：温度记录氧化还原环境陡山沱组后生动物气候记录碳循环高分辨率

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元古代海洋化学与早期真核生物的协同演化

元古代海洋化学与早期真核生物的协同演化

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中国古生物学会第26届学术年会

作者：李超 Gordon D.Love timothy w.lyons 储雪蕾罗根明谢树成中国地质大学(武汉)生物地质与环境地质国家重点实验室 Department of Earth Sciences University of CaliforniaRiversideCA92521USA 中国科学院地质与地球物理研究所岩石圈演化国家重点实验室

地球上的生命演化(特别是真核生物和早期动物的演化)与海洋的氧化还原状态密切相关。然而,对于早期地球海洋化学的演化却存在着很大的争议。早期传统模型(例如:Holland,2006)认为,尽管条带状硅铁建造(BandedIronFormation-BIF)在新元古... 详细信息

地球上的生命演化(特别是真核生物和早期动物的演化)与海洋的氧化还原状态密切相关。然而,对于早期地球海洋化学的演化却存在着很大的争议。早期传统模型(例如:Holland,2006)认为,尽管条带状硅铁建造(BandedIronFormation-BIF)在新元古代大冰期时期曾短暂出现,但是由于大气的逐步氧化,太古代-古元古代铁化的(即含Fe2+)深部海洋在大约18亿年前就已经彻底氧化,这样海水中的Fe2+被氧化沉淀,从而结束了全球范围内的BIF沉积。

关键词：元古代海洋化学真核生物串岭沟组铁化学硫同位素

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Partitioning Anatolian Kinematics into Tectonic Escape and Slab Rollback Dominated Domains

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Journal of Earth Science 2024年第3期35卷 758-768页

作者： Jiannan Meng timothy M.Kusky Erdin Bozkurt Hao Deng Ozan Sinoplu State Key Laboratory of Geological Processes and Mineral Resources Center for Global TectonicsSchool of Earth SciencesChina University of GeosciencesWuhan 430074China Badong National Observatory and Research Station for Geohazards China University of GeosciencesWuhan 430074China Department of Geological Engineering Middle East Technical University06800 AnkaraTurkey Department of Geosciences Auburn UniversityAuburn AL 36849USA

Anatolia is the global archetype of tectonic escape,as witnessed by the devastating 2023 Kahramanmaraş Earthquake sequence,and the 2020 Samos Earthquake,which show different kinematics related to the framework of the escape *** Positioning System(GPS)motions of the wedge-shaped plate differ regionally from northwestwards to southwestwards(from east to west).Anatolia was extruded westward from the Arabian-Eurasian collision along the North and East Anatolian fault systems,rotating counterclockwise into the oceanic free-faces of the Mediterranean and Aegean,with dramatic extension of western Anatolia in traditional ***,which is the dominant mechanism for this change in kinematics,extrusion related to the Arabia/Eurasia collision or rollback of the African slab beneath western Anatolia is still *** assess the dominant driving mechanisms across Anatolia,we analyze recent GPS velocity datasets,and decomposed them into N-S and E-w components,revealing that westward motion is essentially constant across the whole plate and consistent with the slip rates of the North and East Anatolia fault zones,while southward components increase dramatically in the transition area between central and western Anatolia,where a slab tear is *** phenomenon is related to different tectonic driving *** ArabiaEurasia collision drives the Anatolian Plate uniformly westwards while western Anatolia is progressively more affected by the southward retreating African subducting slab west of the Aegean/Cypriot slab tear,which significantly increases the southward component of the velocity field and causes the apparent curve of the whole modern velocity *** 2020 and 2023 earthquake focal mechanisms also confirm that the northward colliding Arabian Plate forced Anatolia to the west,and the retreating African slab is pulling the upper plate of western Anatolian apart in *** propose that the Anatolian Plate is moving westwards as

关键词： tectonics neotectonics tectonic escape slab rollback Anatolian Plate GPS velocity field geodynamics.

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Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok timothy G.white Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

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Quantitative Applications of weather Satellite Data for Nowcasting:Progress and Challenges

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Journal of Meteorological Research 2024年第3期38卷 399-413页

作者： Jun LI Jing ZHENG Bo LI Min MIN Yanan LIU Chian-Yi LIU Zhenglong LI wPaul MENZEL timothy J.SCHMIT John L.CINTINEO Scott LINDSTROM Scott BACHMEIER Yunheng XUE Yayu MA Di DI Han LIN Innovation Centre for Fengyun Meteorological Satellite(FYSIC) National Satellite Meteorological CentreChina Meteorological AdministrationBeijing100081China School of Atmospheric Sciences and Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen University and Southern Laboratory of Ocean Science and EngineeringZhuhai519082China Key Laboratory of Geographic Information Science(Ministry of Education) East China Normal UniversityShanghai200241China Research Center for Environmental Changes Academia SinicaTaipei11529China Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonMadisonWI53706USA Sensors and Calibration Branch STAR/NESDISMadisonWI53706USA wuxi University Wuxi214105China School of Computer Science Chengdu University of Information TechnologyChengdu610225China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China Key Laboratory of Spatial Data Mining and Information Sharing of Ministry of Education National and Local Joint Engineering Research Center of Satellite Geospatial Information TechnologyFuzhou UniversityFuzhou350108China

Monitoring and predicting highly localized weather events over a very short-term period,typically ranging from minutes to a few hours,are very important for decision makers and public *** these events usually relies on radar observations through monitoring and *** advanced high-resolution imaging and sounding observations from weather satellites,nowcasting can be enhanced by combining radar,satellite,and other data,while quantitative applications of those data for nowcasting are advanced through using machine learning *** applications include monitoring the location,impact area,intensity,water vapor,atmospheric instability,precipitation,physical properties,and optical properties of the severe storm at different stages(pre-convection,initiation,development,and decaying),identification of storm types(wind,snow,hail,etc.),and predicting the occurrence and evolution of the *** observations can provide information on the environmental characteristics in the preconvection stage and are very useful for situational awareness and storm *** paper provides an overview of recent progress on quantitative applications of satellite data in nowcasting and its challenges,and future perspectives are also addressed and discussed.

关键词： weather satellite quantitative applications nowcasting pre-convection

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Prehospital transdermal glyceryl trinitrate for ultra- acute ischaemic stroke: data from the RIGHT- 2 randomised sham- controlled ambulance trial

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Stroke & Vascular Neurology 2024年第1期9卷 38-49,I0035-I0046页

作者： Jason Philip Appleton Lisa J woodhouse Craig S Anderson Sandeep Ankolekar Lesley Cala Mark Dixon timothy J England Kailash Krishnan Grant Mair Keith w Muir John Potter Christopher I Price Marc Randall Thompson G Robinson Christine Roffe Else C Sandset Jeffrey L Saver Angela Shone Aloysius Niroshan Siriwardena Joanna M wardlaw Nikola Sprigg Philip M Bath Stroke University Hospitals Birmingham NHS Foundation TrustBirminghamUK Institute of Applied HealthResearch University of Birmingham College of Medical and Dental SciencesBirminghamUK Stroke Trials Unit Mental Health and Clinical NeurosciencesUniversity of NottinghamNottinghamUK Faculty of Medicine The George Institute for Global HealthSydneyNew South WalesAustralia The George Institute China at Peking University Health Science Center BeijingChina Neurology Royal Prince Alfred HospitalSydney Health PartnersSydneyNew South WalesAustralia Department of Neurology King's College Hospital NHS Foundation TrustLondonUK Faculty of Health and Medical Sciences University of Western AustraliaCrawleyWestern AustraliaAustralia East Midlands Ambulance Service NHS Trust NottinghamUK Stroke Queen's Medical CentreNottingham University Hospitals NHS TrustNottinghamUK Centre for Clinical Brain Sciences Dementia Research InstituteUniveristy of EdinburghEdinburghUK Institute of Neurology and Psychology University of GlasgowGlasgowUK Bob Champion Research and Education Building University of East AngliaNorwichUK Institute of Neuroscience Newcastle UniversityNewcastle upon TyneUK Department of Neurology Leeds Teaching Hospitals NHS TrustLeedsUK Department of Cardiovascular Sciences and NIHR Leicester Biomedical Research Centre University of LeicesterLeicesterUK Stroke Research in Stoke Institute for Science and Technology in MedicineKeele UniversityStoke-on TrentUK Department of Neurology Oslo University HospitalOsloNorway Research and Development Norwegian Air Ambulance FoundationOsloNorway Department of Neurology and Comprehensive Stroke Center David Geffen School of MedicineUCLALos AngelesCaliforniaUSA Research and Graduate Services University of NottinghamNottinghamUK Community and Health Research Unit University of LincolnLincolnUK

Background The effect of transdermal glyceryl trinitrate(GTN,a nitrovasodilator)on clinical outcome when administered before hospital admission in suspected stroke patients is ***,we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2(RIGHT-2).Methods RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4hours of *** primary outcome was a shift in scores on the modified Rankin scale(mRS)at day *** outcomes included death;a global analysis(wei-Lachin test)containing Barthel Index,EuroQol-5D,mRS,telephone interview for cognitive status-modified and Zung depression scale;and neuroimaging-determined‘brain frailty’*** were reported as n(%),mean(SD),median[IQR],adjusted common OR(acOR),mean difference or Mann-whitney difference(MwD)with 95%*** 597 of 1149(52%)patients had a final diagnosis of ischaemic stroke;age 75(12)years,premorbid mRS>2107(18%),Glasgow Coma Scale 14(2)and time from onset to randomisation 67[45,108]***‘brain frailty’was common:median score 2[2,3](range 0–3).At day 90,GTN did not influence the primary outcome(acOR for increased disability 1.15,95%CI 0.85 to 1.54),death or global analysis(MwD 0.00,95%CI-0.10 to 0.09).In subgroup analyses,there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1hour of symptom onset and in those with more severe *** In patients who had an ischaemic stroke,ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital *** IS ALREADY KNOwN ON THIS TOPIC⇒Transdermal glyceryl trinitrate(GTN)was associat-ed with less death and dependency in those w

关键词： Glasgow nitrate random

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Physical and chemical processes promoting dominance of the toxic cyanobacterium Cylindrospermopsis raciborskii

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Chinese Journal of Oceanology and Limnology 2011年第4期29卷 883-891页

作者： Michele A. BURFORD timothy w. DAVIS Australian Rivers Institute Griffith University Nathan Qld. 4111 Australia

The freshwater cyanobacterium, Cylindrospermopsis raciborskii （woloszyflska） Seenayya and Subba Raju is a common species in lakes and reservoirs globally. In some areas of the world it can produce cytoand hepatotoxins （cylindrospermopsins, saxitoxins）, making blooms of this species a serious health concern for humans. In the last 10 15 years, there has been a considerable body of research conducted on the ecology, physiology and toxin production of this species and this paper reviews these studies with a focus on the cylindrospermopsin （CYN）-producing strains. C. raciborskii has low light requirements, close to neutral buoyancy, and a wide temperature tolerance, giving it the capacity to grow in many lentic waterbodies. It also has a flexible strategy with respect to nitrogen （N） utilisation; being able to switch between utilising fixed and atmospheric N as sources of N fluctuate. Additionally this species has a high phosphate （DIP） affinity and storage capacity. Like many cyanobacteria, it also has the capacity to use dissolved organic phosphorus （DOP）. Changes in nutrient concentrations, light levels and temperature have also been found to affect production of the toxin CYN by this species. However, optimal toxin production does not necessarily occur when growth rates are optimal. Additionally, different strains of C. raciborskii vary in their cell quota of CYN, making it difficult to predict toxin concentrations, based on C. raciborskii cell densities. In summary, the ecological flexibility of this organism means that controlling blooms of C. raciborskii is a difficult undertaking. However, improved understanding of factors promoting the species and toxin production by genetically capable strains will lead to improved predictive models of blooms.

关键词： cyanobacteria freshwater algal toxins nutrients light temperature

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Interaction of obesity and inflammatory bowel disease

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world Journal of Gastroenterology 2016年第35期22卷 7868-7881页

作者： Jason w Harper timothy L Zisman Department of Gastroenterology Swedish Medical CenterWA 98195United States Inflammatory Bowel Disease Program Division of GastroenterologyUniversity of Washington Medical CenterSeattleWA98195 United States

Inflammatory bowel disease(IBD) is a chronic inflammatory condition of unknown etiology that is thought to result from a combination of genetic, immunologic and environmental factors. The incidence of IBD has been increasing in recent decades, especially in developing and developed nations, and this is hypothesized to be in part related to the change in dietary and lifestyle factors associated with modernization. The prevalence of obesity has risen in parallel with the rise in IBD, suggesting a possible shared environmental link between these two conditions. Studies have shown that obesity impacts disease development and response to therapy in patients with IBD and other autoimmune conditions. The observation that adipose tissue produces pro-inflammatory adipokines provides a potential mechanism for the observed epidemiologic links between obesity and IBD, and this has developed into an active area of investigative inquiry. Additionally, emerging evidence highlights a role for the intestinal microbiota in the development of both obesity and IBD, representing another potential mechanistic connection between the two conditions. In this review we discuss the epidemiology of obesity and IBD, possible pathophysiologic links, and the clinical impact of obesity on IBD disease course and implications for management.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Obesity Body mass index

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Observation of ocean current response to 1998 Hurricane Georges in the Gulf of Mexico

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Acta Oceanologica Sinica 2006年第1期25卷 1-14页

作者： ZHENG Quanan LAI Ronald J HUANG Nortlen E PAN Jiayi LIU w timothy Department of Atmospheric and Oceanic Science University of Maryland College Park Maryland 20742 USA Minerals Management Service U S Department of the Interior Hemdon Virginia 20170 USA Ocean and Ice Branch NASA Goddard Space Flight Center Greenbelt Maryland 20771 USA Department of Environmental and Biomolecular Systems Oregon Graduate Institute Beaverton Oregon 97006 USA Jet Propulsion Laboratory California Institute of Technology Pasadena California 91109 USA

The ocean current response to a hurricane on the shelf-break is examined. The study area is the DeSoto Canyon in the northeast Gulf of Mexico, and the event is the passage of 1998 Hurricane Georges with a maximum wind speed of 49 m/s. The data sets used for analysis consist of the mooring data taken by the Field Program of the DeSoto Canyon Eddy Intrusion Study, and simultaneous winds observed by NOAA （National Oceanic and Atmospheric Administration） Moored Buoy 42040. Time-depth ocean current energy density images derived from the observed data show that the ocean currents respond almost immediately to the hurricane with important differences on and offthe shelf. On the shelf, in the shallow water of 100 m, the disturbance penetrates rapidly downward to the bottom and forms two energy peaks, the major peak is located in the mixed layer and the secondary one in the lower layer. The response dissipates quickly after external forcing disappears. Offthe shelf, in the deep water, the major disturbance energy seems to be trapped in the mixed layer with a trailing oscillation; although the disturbance signals may still be observed at the depths of 500 and 1 290 m. Vertical dispersion analysis reveals that the near-initial wave packet generated offthe shelf consists of two modes. One is a barotropic wave mode characterized by a fast decay rate of velocity amplitude of 0.020 s^-, and the other is baroclinic wave mode characterized by a slow decay rate of 0.006 9 s^-1. The band-pass-filtering and empirical function techniques are employed to the frequency analysis. The results indicate that ialf frequencies shift above the local inertial frequency. On the shelf, the average frequency is 1.04fin the mixed layer, close to the diagnosed frequency of the first baroclinic mode, and the average frequency increases to 1.07fin the thermocline. Offthe shelf, all frequencies are a little smaller than the diagnosed frequency of the first mode. The average frequency decreases from 1.035

关键词： shelf dynamics hurricane ocean current air-sea interaction

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