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Continental crust formation at arcs, the arclogite ‘‘delamination''cycle, and one origin for fertile melting anomalies in the mantle

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Science Bulletin 2015年第13期60卷 1141-1156页

作者： Cin-Ty A.lee don l.anderson Department of Earth Science MS-126 Rice University Department of Geological and Planetary Sciences California Institute of Technology

The total magmatic output in modern arcs,where continental crust is now being formed, is believed to derive from melting of the mantle wedge and is largely basaltic. Globally averaged continental crust, however, has an andesitic bulk composition and is hence too silicic to have been derived directly from the mantle. It is well known that one way this imbalance can be reconciled is if the parental basalt differentiates into a mafic garnet pyroxenitic residue/cumulate(‘‘arclogite'') and a complementary silicic melt, the former foundering or delaminating into the mantle due to its high densities and the latter remaining as the *** the Sierra Nevada batholith in California as a case study, the composition of mature continental arc crust is shown in part to be the product of a cyclic process beginning with the growth of an arclogite layer followed by delamination of this layer and post-delamination basaltic underplating/recharge into what remains of the continental crust.A model is presented, wherein continuous arc magmatism and production of arclogites in continental arcs are periodically punctuated by a delamination event and an associated magmatic pulse every *10–30 My. The recycling flux of arclogites is estimated to be *5 %–20 % that of oceanic crust recycling by subduction. Delaminated arclogites have the necessary trace-element compositions to yield time-integrated isotopic compositions similar to those inferred toexist as reservoirs in the mantle. Because of their low melting temperatures, such pyroxenites may be preferentially melted, possibly forming a component of some hotspot magmas.

关键词： Pyroxenite Eclogite Delamination Cumulate Continental crust

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作为行星的地球:范例与疑难

地震地质译丛

地震地质译丛 1985年第4期 1-9页

作者： don l.anderson 宿俭

大多数考虑全球问题的研究者往往按一套地球内部是如何起作用的普遍假定进行工作,这些假定可以概括为如下范例。地幔对流是定常的,是由地幔自行加热或地核上来的热造成的热膨胀驱动的。板块构造或类似的构造,包括向深部俯冲,在整个地史... 详细信息

大多数考虑全球问题的研究者往往按一套地球内部是如何起作用的普遍假定进行工作,这些假定可以概括为如下范例。地幔对流是定常的,是由地幔自行加热或地核上来的热造成的热膨胀驱动的。板块构造或类似的构造,包括向深部俯冲,在整个地史大部分时期内都在起作用,大陆是这一体系中的不活动单元。视极移总是受板块运动控制的,而不是受整个地幔相对于地极的运动控制的。玄武岩是富含橄榄石的石榴石橄榄岩地幔的部分熔体。大洋中脊玄武岩或拉斑玄武岩是深约

关键词：榴辉岩相大洋中脊亲石元素大离子洋中脊地球石榴石岩部分熔融基性岩玄武岩单斜辉石大洋岩石圈大地水准面高海洋地壳大洋地壳岛状硅酸盐矿物橄榄石残余熔浆行星

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670公里转变带以上地幔的化学不均匀性

地质科技通报 1986年第1期 93-93页

作者： don l.anderson ,高山

回答地幔的化学成分和地幔对流的规模这两个相关的问题,需要利用地震学及岩石学资料.一般,岩石学家们认为地幔的成分基本是均匀的.通常假设其中的不连续面代表了某种富橄揽石物质的等化学相变,而不是化学分界.因此,由地震方法探测到的40... 详细信息

回答地幔的化学成分和地幔对流的规模这两个相关的问题,需要利用地震学及岩石学资料.一般,岩石学家们认为地幔的成分基本是均匀的.通常假设其中的不连续面代表了某种富橄揽石物质的等化学相变,而不是化学分界.因此,由地震方法探测到的400km及670km这两个分界面,被认为分别代表“橄榄石—尖晶石”相变及”尖晶石—后尖晶石(Spinel post—Spinel)相变.由于地震波速在670km处迅速增加,因此这个不连续面更有意义.此分界面十分清楚,因为它即是短周期地震波的良好反射层,又是地震活动的下界一在此边界以下尚未发现可确信定位的地震.上述观察说明“670”是一个为对流提供了屏障的化学界面.***等近来计算了各种可能

关键词：化学不均匀性岩石学不连续面间断面地震学地球科学转变带

The effects of indigenous prescribed fire on riparian vegetation in central California

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Ecological Processes 2013年第1期2卷 245-253页

作者： don l Hankins Department of Geography and Planning California State University-ChicoChicoCAUSA

Introduction:Fire has a long history,but little documented role,as a process in riparian *** millennia California Indians have applied fire to riparian ecosystems for a variety of purposes,but the effects of such fires on riparian vegetation are poorly known outside of traditional knowledge structures of indigenous ***:This study involved the seasonal application of fire based on traditional ecological knowledge versus alternate burn methods to assess fire effects on riparian vegetation in central ***:While the annual variation amongst treatments was not significant,the results of this study suggest that fall burns support higher overall richness and native species richness;spring burns yield a decrease in overall richness,but an increase in native species richness;and summer burns contribute to an initial decline in overall and native species *** evenness indices of treatments increase most with spring and summer ***:These findings are key to understanding the seasonal role of fire in managing native species in areas prone to non-native or other invasive *** research demonstrates the application of traditional ecological knowledge to facilitate an understanding of how prescribed fire could aid in the management and conservation of riparian ecosystems.

关键词： Riparian California Indian Fire Indigenous Traditional ecological knowledge

Integrative genomic and transcriptomic profiling of pulmonary sarcomatoid carcinoma identifies molecular subtypes associated with distinct immune features and clinical outcomes

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Cancer Innovation 2024年第3期3卷 81-94页

作者： Sahil Seth Runzhe Chen Yang liu Junya Fujimoto lingzhi Hong Alexandre Reuben Susan Varghese Carmen Behrens Tina McDowell luisa Solis Soto Cara Haymaker Annikka Weissferdt Neda Kalhor Jia Wu Xiuning le Natalie I Vokes Chao Cheng John V.Heymach don l.Gibbons P.Andrew Futreal Ignacio IWistuba Humam Kadara Jianhua Zhang Cesar Moran Jianjun Zhang Department of Genomic Medicine The University of Texas MD Anderson Cancer CenterHoustonTexasUSA TRACTION The University of Texas MD Anderson Cancer CenterHoustonTexasUSA Graduate School of Biomedical Sciences The University of Texas MD Anderson and the University of Texas Health Science CenterHoustonTexasUSA Department of Thoracic/Head and Neck Medical Oncology The University of Texas MD Anderson Cancer CenterHoustonTexasUSA Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer CenterHoustonTexasUSA Department of Epidemiology The University of Texas MD Anderson Cancer CenterHoustonTexasUSA Department of Pathology The University of Texas MD Anderson Cancer CenterHoustonTexasUSA Department of Imaging Physics The University of Texas MD Anderson Cancer CenterHoustonTexasUSA Department of Medicine Baylor College of MedicineHoustonTexasUSA

Background:Pulmonary sarcomatoid carcinoma(PSC)is a rare and aggressive subtype of non-small cell lung cancer(NSClC),characterized by the presence of epithelial and sarcoma-like *** molecular and immune landscape of PSC has not been well ***:Multiomics profiling of 21 pairs of PSCs with matched normal lung tissues was performed through targeted high-depth DNA panel,whole-exome,and RNA *** describe molecular and immune features that define subgroups of PSC with disparate genomic and immunogenic features as well as distinct clinical ***:In total,27 canonical cancer gene mutations were identified,with TP53 the most frequently mutated gene,followed by ***,most TP53 and KRAS mutations were earlier genomic events mapped to the trunks of the tumors,suggesting branching evolution in most PSC *** identified two distinct molecular subtypes of PSC,driven primarily by immune infiltration and *** Immune High(IM-H)subtype was associated with superior survival,highlighting the impact of immune infiltration on the biological and clinical features of localized ***:We provided detailed insight into the mutational landscape of PSC and identified two molecular subtypes associated with ***-H tumors were associated with favorable recurrence-free survival and overall survival,highlighting the importance of tumor immune infiltration in the biological and clinical features of PSCs.

关键词： genomic immune pulmonary sarcomatoid carcinoma survival

Endoscopic ultrasound-guided portal pressure gradient identifies patients with previously undiagnosed clinically significant portal hypertension

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Portal Hypertension & Cirrhosis 2024年第2期3卷 67-74页

作者： Jerome C.Edelson Scott F.D.Edelson John G.Quiles Cyrus V.Edelson Eric M.Montminy Christian l.Horn John P.Magulick don C.Rockey Department of Gastroenterology and Hepatology Brooke Army Medical CenterFort Sam HoustonTexasUSA Department of Medicine Uniformed Services University of the Health SciencesBethesdaMarylandUSA Department of Medicine Brooke Army Medical CenterFort Sam HoustonTexasUSA John H.Stroger Jr.Hospital of Cook County ChicagoIllinoisUSA Digestive Disease Research Center Medical University of South CarolinaCharlestonSouth CarolinaUSA

Aims:Portal hypertension(PH)is a complication of cirrhosis that leads to hepatic *** the portal pressure gradient(PPG)provides valuable information for disease assessment,staging,and *** this study,we aimed to report the utilization of endoscopic ultrasound(EUS)-guided PPG(EUS-PPG)measurements in a real-world ***:This retrospective analysis included patients at a tertiary care center who underwent EUS-PPG between February 2021 and May *** most common indication was to establish or exclude the diagnosis of cirrhosis,followed by an assessment of surgical risk in the setting of suspected *** demographic and clinical data were collected,and statistical analysis was performed using the Student's t ***:Eighteen patients underwent *** success was achieved in 17 of the 18 *** complications were *** mean scores of Child-Pugh,Model for End-Stage liver Disease-Sodium,and Fibrosis-4 scores were 5.1±0.5,9.0±3.0,and 3.7±4.5,*** the 18 patients,two presented with esophageal varices and six with portal hypertensive *** mean PPG was 5.8±4.5 mmHg,and five patients exhibited clinically significant PH(CSPH).Of the 18 patients,15 underwent concurrent EUS-liver biopsy,which was 100%successful and provided diagnostic histology for all *** PPG data led to changes in the clinical management of 17 ***:EUS-PPG is safe and technically *** Child-Pugh score did not correlate well with the presence of CSPH;however,PPG measurements resulted in changes in the management of almost all *** studies correlating EUS-PPG with other assessments of liver diseases are required.

关键词： EUS portal hypertension portal pressure gradient

New theory of the Earth

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Episodes 2008年第4期31卷 452-453页

作者： don l. anderson

From time to time the phrase ＇Theory of the Earth＇ occurs among titles in Earth science history. It usually happens after times of changing major scientific paradigms. A first peak occurred in the Renaissance at the time of the origin of modern science with the introduction of the word geology by Ulisse Aldrovandi in 1603; and the phrase moved around in the controversy about the origin of marine fossils found in mountains, with works by Alessandro degli Alessandri （about 1500）, Girolamo Cardano （1550）, Gabriele Falloppio （1564）, Bernard Palissy （1580）, Andrea Cesalpino （1596）, and Simeone Maioli （1597）.

关键词：地球科学地质学复活理论研究

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地壳究竟在哪里

地质科技情报 1990年第2期9卷 71-74页

作者： don.l .anderson 杨开辉

矿物学资料与比较行星学提出了一个有争议的新假说一绝大部分地壳可能被埋在地幔深处.地球科学家早就猜想,在太阳系的星球中,我们星球的地质特征是独特的.在跨入行星探索时代的今天,比较行星学已经有力地证明了这个猜想.行星间相似性和... 详细信息

矿物学资料与比较行星学提出了一个有争议的新假说一绝大部分地壳可能被埋在地幔深处.地球科学家早就猜想,在太阳系的星球中,我们星球的地质特征是独特的.在跨入行星探索时代的今天,比较行星学已经有力地证明了这个猜想.行星间相似性和差异性为我们提供了尚待发展的、关于行星(包括地球)起源与演化的普遍性理论的原始资料.我们已经知道,现存的一套关于地球的理论、规律和修正并来提供其他行星具体结构的约束条件.与其进一步修正这些“规律”,不如现在开始新的计划——即使这意味着放弃那些为绝大多数地球科学家“信”以为真的信条和假设.

关键词：地壳地幔

Coastal eutrophication, land use changes and Ceratium furca (Dinophyceae) blooms in Pago Pago Harbor, American Samoa 2007-2009

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Chinese Journal of Oceanology and limnology 2011年第4期29卷 790-794页

作者： Steve l. MORTON Andrew SHUlER Jeff PATERNOSTER Sharon FANOlUA don VARGO NOAA/National Ocean Service Marine Biotoxins Program Charleston SC 29412 USA American Samoa Community College Community and Natural Resources Pago Pago American Samoa 96799 USA

The bloom forming dinoflagellate, Ceratium furca, has been linked with coastal eutrophication worldwide in tropical and subtropical locations. During the summer of 2007, an unusual 6-month long bloom of C. furca was observed in Pago Pago Harbor, Tutuila Island, American Samoa. Incidents of dinoflagellate blooms in this area have not been previously reported. The bloom was first reported in May and dissipated in November 2007. In February-March 2009, a similar C. furca bloom was observed. During both blooms, no fish mortality events were reported. Maximum cell counts were observed on September 20, 2007 at 9 200 cell/ml. At this time, total nitrogen was measured at 1.2 mg/l while total phosphate was below detection limits. Changes in land use practices may have been the primary driver of these blooms. Intense fertilization of athletic fields coupled with ineffective management strategies is hypothesized to have a direct link to the increase in nutrients found in the Pago Pago Harbor and may have been the trigger for the initialization of these blooms. During 2008, the fields were not used due to an infestation of the fire ant, Solenopsis geminata. Once controlled, the fields were opened again in 2009 and fertilizers were applied in January, a month before the bloom was observed.

关键词： eutrophication American Samoa Ceratium furca