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Isotope Geochemistry of Volcanic Rocks from the Barton Peninsula,King George Island,Antarctica

Journal of Earth Science 2011年第1期22卷 40-51页

作者： Jeong Hwang 郑祥身 edward m ripley Jong-Ik Lee Dongbok Shin Department of Geological Engineering Daejeon University Institute of Geology and Geophysics Chinese Academy of Sciences Department of Geological Sciences Indiana University Korea Polar Research Institute Department of Geological Sciences Kongju University

C, O, H, S and Sr isotopes were investigated to characterize the isotopic composition of the Paleocene-Eocene volcanic rocks in Barton Peninsula, King George Island, Antarctica. The analyzed samples of volcanic rocks cover a range from basalt to andesite. The δ 13C and 61SO values of calcite in volcanic rocks range from -7.5‰ to -3.2‰ and 0.4‰ to 5.1‰, respectively. The homogenous δ 13C cal and depleted δ18 Ccal values relative to primary magmatic values reflect the effect of high temperature alteration of volcanic rocks. The δ18 O of volcanic rocks ranges from -1.1‰ to 7.2‰, and the majority of values are significantly lower than those of primary magmatic values. The low δ18 O WR values are compatible with high temperature alteration. The initial values of 87Sr/86Sr of volcanic rocks span a narrow range from 0.703 312 to 0.703 504 which belong to the present mid-oceanic ridge basalt. The values of 87Sr/86Sr of volcanics in the Barton Peninsula are similar to those determined in the Fildes Peninsula, King George Island. The δD WR and H2O contents of volcanic rocks range from -74‰ to -66‰ and 0.67 wt.% to 2.74 wt.%, respectively. The higher δD WR and H2O wt.% of volcanic rocks relative to fresh basalts also result from high temperature alteration. Sulfur isotope compositions of the volcanic rocks range from -12.5‰ to -7.0‰; these values may represent fractionation accompanying partial oxidation of magmatic S or incorporation of some bacteriogenic sulfide. The low S contents and negative correlation with C and H2O reflect the formation of calcite and breakdown of sulfide as a result of high temperature water-rock interaction.

关键词： isotope volcanic rock high temperature alteration Antarctica.

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稳定和放射性同位素在Cu-Ni-PGE岩浆矿床研究中的应用:实例及需要注意的问题(英文)

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地学前缘 2007年第5期14卷 124-132页

作者： edward m.ripley Department of Geological Sciences Indiana University

硫、氧同位素和放射性同位素比值在示踪岩浆与围岩的反应及在岩浆镍-铜-铂族元素矿床成因中同化过程的重要性方面有很大作用。如1.1Ga的Duluth杂岩、Norilsk地区二叠-三叠纪侵入岩和1.4Ga的Kabanga侵入岩体中矿床的硫同位素测定结果证... 详细信息

硫、氧同位素和放射性同位素比值在示踪岩浆与围岩的反应及在岩浆镍-铜-铂族元素矿床成因中同化过程的重要性方面有很大作用。如1.1Ga的Duluth杂岩、Norilsk地区二叠-三叠纪侵入岩和1.4Ga的Kabanga侵入岩体中矿床的硫同位素测定结果证明硫来自含硫化物和硫酸盐的围岩。1.3Ga的VoisbeysBay矿床矿石的硫同位素δ34S值通常落入公认的地幔硫同位素组成范围(0±2‰)内,而对其元古宙变质沉积围岩进行的详细研究结果显示δ34S的平均值也在此范围。全面了解同位素组成的潜在混染对合理评价提供硫来源的围岩在矿石形成中的作用是非常必要的。用氧同位素和放射性同位素示踪岩浆和围岩相互作用时,必须在开放体系没有扰动同位素系统情况下进行。在氧同位素体系和放射性同位素体系(如Re/Os、Pb同位素体系)中,元素在热液条件下活动性强或主相没有发生同位素交换与吸收,都会导致低温热液过程掩盖高温过程。只有在进行详细的岩相观察和单矿物分析之后,再应用围岩混染同位素模式才是有意义的。

关键词：硫同位素氧同位素放射性同位素岩浆-围岩相互作用

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含硫化物镁铁质-超镁铁质侵入体中橄榄石mg、Ni含量的制约:原理、模式及Voisey's Bay侵入体样品研究(英文)

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地学前缘 2007年第5期14卷 177-185页

作者： Anthony J.Naldrett edward m.ripley Department of Geology University of TorontoToronto M5S 3B1Canada Department of Earth Sciences Indiana UniversityBloomingtonIN 47405USA

镁铁质-超镁铁质岩浆结晶分离早期形成镁铁矿物,镁铁矿物中的Ni和mg是相容元素。随着结晶分离作用的进行,Ni、mg在硅酸盐岩浆及后形成的硅酸盐物质中的丰度下降。橄榄石中Ni含量及硅酸盐物质mgO/FeO比值都与母岩浆的相关值相关,据此可... 详细信息

镁铁质-超镁铁质岩浆结晶分离早期形成镁铁矿物,镁铁矿物中的Ni和mg是相容元素。随着结晶分离作用的进行,Ni、mg在硅酸盐岩浆及后形成的硅酸盐物质中的丰度下降。橄榄石中Ni含量及硅酸盐物质mgO/FeO比值都与母岩浆的相关值相关,据此可推断母岩浆的信息,它们之间可由实验测得的系数相联系。当岩浆饱和硫化物时,在结晶分离过程中硫化物珠滴会与镁铁硅酸盐物质一道析出,同时,与硫化物非饱和岩浆相比,过多的Ni会随之析出。这也反映在Ni、mg含量比无硫化物分离时有更迅速的降低上。Ni、mg含量变化值可以在VoiseysBay侵入体的模式曲线上反映出,加拿大Labrador的这一侵入体赋存了一个世界级的Ni-Cu-Co硫化物矿床。过去的作法是将侵入体中橄榄石的Ni、mg含量与Simkin和Smith得出的各种火成岩中橄榄石的Ni、mg含量相比较以确定Ni亏损,进而假定橄榄石来自硫化物饱和、有经济价值的岩浆。现在的研究显示这种简单的对比会导致错误。将样品数据与模式曲线对比并反映出侵入体矿物结晶堆积特征是重要的方法。使用这一方法,样品数据能很好地被模式曲线拟合。以在VoiseysBay的研究为例,当硫化物液相与硅酸盐矿物被去除后,硫化物非饱和的分离作用期就会显现出来,随后是硅酸盐结晶作用期。

关键词：橄榄石镍基性-超基性岩浆硫化物矿床

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岩浆型铜镍硫化物矿床铁同位素特征

岩浆型铜镍硫化物矿床铁同位素特征

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中国矿物岩石地球化学学会第17届学术年会

作者：丁昕 edward m.ripley 王文忠黄方中国科学技术大学地球与空间科学学院壳幔物质与环境重点实验室 Indiana University Department of Earth and Atmospheric Sciences

＜正＞岩浆型铜镍硫化物矿床通常产于基性、超基性岩体中,铜、镍和铂族元素赋存于硫化物中,其典型的硫化物组合为磁黄铁矿、镍黄铁矿和黄铜矿。本次研究以四川冷水箐铜镍硫化物矿床为例,分析共生磁黄铁矿和黄铜矿的Fe同位素组成,揭示成... 详细信息

＜正＞岩浆型铜镍硫化物矿床通常产于基性、超基性岩体中,铜、镍和铂族元素赋存于硫化物中,其典型的硫化物组合为磁黄铁矿、镍黄铁矿和黄铜矿。本次研究以四川冷水箐铜镍硫化物矿床为例,分析共生磁黄铁矿和黄铜矿的Fe同位素组成,揭示成矿过程中Fe同位素特征和变化规律。冷水箐铜镍硫化物矿床位于四川盐边高家村岩体铁镁质-超铁镁质杂岩体的东侧,是一

关键词：铜镍硫化物矿床成矿过程岩浆演化铁同位素

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Surgeon preferences in the treatment of thumb carpometacarpal osteoarthritis

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World Journal of Orthopedics 2024年第5期15卷 435-443页

作者： edward J Wu Bradley W Fossum Wyatt Vander Voort Christopher O Bayne Robert m Szabo Department of Orthopedic Surgery University of Minnesota Medical SchoolMinneapolisMN 55455United States Department of Orthopaedic Surgery UC Davis School of MedicineSacramentoCA 95817United States

BACKGROUND Primary thumb carpometacarpal(CmC)osteoarthritis is one of the most common conditions encountered by hand *** the vast number of operations that have been proposed,none have demonstrated results significantly superior to trapeziectomy *** The purpose of our study was to determine why surgeons opt for their technique in treating CmC *** A cross-sectional survey of active members of the American Society for Surgery of the Hand was conducted to evaluate the reasons behind their preferred technique in the treatment of isolated thumb CmC *** were contacted by email once and provided with a link to a de-identified survey consisting of 5 treatment questions and 5 demographic *** Of 950 responses were received.40.5%of surgeons preferred trapeziectomy+ligament reconstruction tendon interposition(LRTI),followed by trapeziectomy+suspensionplasty(28.2%),suture button suspension(5.9%),trapeziectomy alone(4.6%),prosthetic arthroplasty(3.2%),arthrodesis(1.1%),and other(6.6%).Proponents of trapeziectomy+LRTI cited familiarity(73.2%),exposure during fellowship(48.8%)and less proximal migration(60%)to be the main reasons affecting their *** who preferred trapeziectomy+suspensionplasty most reported simplicity(74.9%),fewer complications(45.3%),less proximal migration(43.8%),and avoidance of autogenous tissue harvest(42.7%).Advocates of suture button suspension cited avoidance of autogenous tissue harvest(80.4%),shorter immobilization(76.8%),and quicker recovery(73.2%)with their *** of trapeziectomy alone cited simplicity(97.7%),fewer complications(86.4%),and avoidance of autogenous tissue harvest(59.1%).In their comments,45%of surgeons choosing trapeziectomy alone cited evidence as an additional *** of prosthetic arthroplasty cited improved pinch strength(83.3%)and improved range of motion(63.3%),while those preferring arthrodesis cited better pinch strength(90%)and freque

关键词： Thumb carpometacarpal Osteoarthritis Trapeziectomy Ligament reconstruction tendon interposition Suspensionplasty Preferences Trends

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DEm analysis of the influence of stirrer design on die filling with forced powder feeding

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Particuology 2024年第5期88卷 107-115页

作者： Chao Zheng edward Yost Ariel R.muliadi Nicolin Govender Ling Zhang Chuan-Yu Wu School of Chemistry and Chemical Engineering University of SurreyGuildfordGU2 7XHUnited Kingdom Small molecule Pharmaceutics GenentechInc.One DNA WaySouth San FranciscoCA94080USA

Die filling is a critical stage during powder compaction,which can significantly affect the product quality and *** this paper,a forced feeder is introduced attempting to improve the filling performance of a lab-scale die filling *** die filling process is analysed with a graphics processing units(GPU)enhanced discrete element method(DEm).Various stirrer designs are assessed for a wide range of process settings(i.e.,stirrer speed,filling speed)to explore their influence on the die filling performance of free-flowing *** results show that die filing with the novel helical-ribbon(i.e.,type D)stirrer design exhibits the highest filling ratio,implying that it is the most robust stirrer design for the feeder configuration ***,die filling performance with the type D stirrer design is a function of the stirrer speed and the filling speed.A positive variation of filling ratio(ηf>0%)can be ensured over the whole range of filling speed by adjusting the stirrer speed(i.e.,increasing the stirrer speed).The approach used in this study can not only help understand how the stirrer design affects the die filling performance but also guide the optimization of feeder system and process settings.

关键词： Discrete element method Die filling Forced feeding Stirrer design GPU computing

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Integrated Single-cell multiomic Analysis of HIV Latency Reversal Reveals Novel Regulators of Viral Reactivation

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 67-88页

作者： manickam Ashokkumar Wenwen mei Jackson J.Peterson Yuriko Harigaya David m.murdoch David m.margolis Caleb Kornfein Alex Oesterling Zhicheng Guo Cynthia D.Rudin Yuchao Jiang edward P.Browne Department of medicine University of North Carolina at Chapel HillChapel HillNC 27599USA HIV Cure Center University of North Carolina at Chapel HillChapel HillNC 27599USA Department of Biostatistics University of North Carolina at Chapel HillChapel HillNC 27599USA Department of microbiology and Immunology University of North Carolina at Chapel HillChapel HillNC 27599USA Department of Genetics University of North Carolina at Chapel HillChapel HillNC 27599USA Department of medicine Duke UniversityDurhamNC 27708USA Department of Computer Science Duke UniversityDurhamNC 27708USA Department of Statistics Texas A&M UniversityCollege StationTX 77843USA Department of Biology Texas A&M UniversityCollege StationTX 77843USA Department of Biomedical Engineering Texas A&M UniversityCollege StationTX 77843USA

Despite the success of antiretroviral therapy,human immunodeficiency virus(HIV)cannot be cured because of a reservoir of latently infected cells that evades *** understand the mechanisms of HIV latency,we employed an integrated single-cell RNA sequencing(scRNA-seq)and single-cell assay for transposase-accessible chromatin with sequencing(scATAC-seq)approach to simultaneously profile the transcriptomic and epigenomic characteristics of~125,000 latently infected primary CD4^(+)T cells after reactivation using three different latency reversing *** expressed genes and differentially accessible motifs were used to examine transcriptional pathways and transcription factor(TF)activities across the cell *** identified cellular transcripts and TFs whose expression/activity was correlated with viral reactivation and demonstrated that a machine learning model trained on these data was 75%-79%accurate at predicting viral ***,we validated the role of two candidate HIV-regulating factors,FOXP1 and GATA3,in viral *** data demonstrate the power of integrated multimodal single-cell analysis to uncover novel relationships between host cell factors and HIV latency.

关键词： HIV latency reversal Primary CD4þT cell Single-cell multiomics HIV-regulating factor machine learning

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Application of Connected Truck Data to Evaluate Spatiotemporal Impact of Rest Area Closures on Ramp Parking

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Journal of Transportation Technologies 2024年第3期14卷 289-307页

作者： Jijo K. mathew Jairaj Desai edward D. Cox Darcy m. Bullock Lyles School of Civil Engineering Purdue University West Lafayette IN USA Indiana Department of Transportation Indianapolis IN USA

Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.

关键词： Connected Truck Data Rest Areas Exit Ramps Truck Parking Commercial Vehicles

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历史和记忆的分与合:一个观念史的分析

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华中师范大学学报（人文社会科学版） 2024年第1期63卷 111-120页

作者：王晴佳上海外国语大学全球文明史研究所上海200083 美国罗文大学历史系新泽西州08028

随着记忆研究在近年的兴起,中文学界出现了“历史记忆”这一名称,含有将两者等同的意思。与之相对照,历史和记忆在西方学术中一直存在某种张力——史学在西方的诞生与对抗记忆的目的相关,之后历史和记忆长期处于一种分离的关系。以兰克... 详细信息

随着记忆研究在近年的兴起,中文学界出现了“历史记忆”这一名称,含有将两者等同的意思。与之相对照,历史和记忆在西方学术中一直存在某种张力——史学在西方的诞生与对抗记忆的目的相关,之后历史和记忆长期处于一种分离的关系。以兰克为代表的近代科学史学,其理论前提是区别“过去”与“现在”,并从后者的立场考察、重构前者,而记忆则常常将两者混为一体。二战之后,兰克史学面临一系列挑战,记忆研究的兴盛便是其中之一。从莫里斯·阿布瓦赫写作《集体记忆》到皮埃尔·诺拉主编《记忆之场》,西方学者试图用记忆来补充和修正历史研究和书写的传统,改进和扩大历史学的方法和范围,促成其内容的更新和革新。但历史研究和记忆研究在近年的合流,仍没有改变两者之间的根本差异。

关键词：近代史学记忆研究历史记忆《记忆之场》莫里斯·阿布瓦赫皮埃尔·诺拉

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Venous thromboembolism prophylaxis in hospitalized elderly patients： Time to consider a ＇mUST＇ strategy

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Journal of Geriatric Cardiology 2011年第2期8卷 114-120页

作者： Kwok m Ho edward Litton Department of Intensive Care medicine Royal Perth Hospital and School of Population Health University of Western Australia Perth WA 6000 Australia

Venous thromboembolism （VTE） is the commonest cause of preventable death in hospitalized patients. Elderly patients have higher risk of VTE because of the high prevalence of predisposing co-morbidities and acute illnesses. Clinical diagnosis of VTE in the elderly patient is particularly difficult and, as such, adequate VTE prophylaxis is of pivotal importance in reducing the mortality and morbidities of VTE. Omission of VTE prophylaxis is, however, very common despite continuous education. A simple way to overcome this problem is to implement universal VTE prophylaxis for all hospitalized elderly patients instead of selective prophylaxis for some patients only according to individual＇ s risk of VTE. Although pharmacological VTE prophylaxis is effective for most patients, a high prevalence of renal impairment and drug interactions in the hospitalized elderly patients suggests that a multimodality approach may be more appropriate. mechanical VTE prophylaxis, including calf and thigh compression devices and/or an inferior vena cava filter, are often underutilized in hospitalized elderly patients who are at high-risk of bleeding and VTE. Because pneumatic compression devices and thigh length stockings are virtually risk free, mechanical VTE prophylaxis may allow early or immediate implementation of VTE prophylaxis for all hospitalized elderly patients, regardless of their bleeding and VTE risk. Although the cost-effectiveness of this multimodality Universal STat （＇mUST＇） VTE prophylaxis approach for hospitalized elderly patients remains uncertain, this strategy appears to offer some advantages over the traditional ＇selective and single-modal＇ VTE prophylaxis approach, which often becomes ＇hit or miss＇ or not implemented promptly in many hospitalized elderly patients. A large clustered randomized controlled trial is, however, needed to assess whether early, multimodality, universal VTE prophylaxis can improve important clinical outcomes of hospitalized elderly patients.

关键词： age bundle of care deep vein thrombosis prevention pulmonary embolism

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