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| 1 | 极高强度他汀治疗对冠状动脉粥样硬化消退的影响——ASTEROID试验显示文摘背景:以前的血管内超声(intravascular ultrasound,IVUS)试验证实,他汀治疗可减缓或阻止动脉粥样硬化的进展,但是迄今尚无应用动脉粥样斑块体积百分比(percent atheroma volume,PAV)证实粥样硬化消退的确切证据。PAV是最严格的评价病变进展和消退的IVUS测量指标。
目标:评价极高强度他汀治疗是否能逆转IVUS确定的冠状动脉粥样硬化。
设计和地点:于美国、加拿大、欧洲和澳大利亚53个社区和3级保健中心进行前瞻性开标盲法终点试验(A Study to Evaluate the Effect of Rosuvastatin on Intravascular Ultrasound-Derived Coronary Atheroma Burden,ASTEROID)。应用马达驱动回撤IVUS评价基线和治疗24个月时冠状动脉粥样斑块负荷。每对基线和随访IVUS测量结果均进行盲法分析。
病例:从2002年11月到2003年10月,507例患者有基线IVUS检查结果,并接受至少1个剂量的研究药物。在24个月后,349例患者具有可用于评估的系列IVUS检查结果。
干预:所有患者均接受瑞舒伐他汀40ms/d强化治疗。
主要观测指标:预先设定了两个一级疗效指标:PAV变化和基线最严重病变10min节段动脉粥样斑块体积变化。二级疗效指标为整个动脉标准化总斑块体积的变化。结果:平均(SD)LDL—C水平由基线时的130.4(34.3)ms/dL降至60.8(20.0)ms/扎,平均下降了53.2%(P〈0.001)。平均(SD)HDL-C水平从基线时的43.1(11.1)ms/dL升至49.0(12.6)ms/dL,平均增加了14.7%(P〈0.001)。整个血管PAV平均(SD)变化为-0.98%(3.15%),中位数为-0.79%(97.5%CI,-1.21%~-0.53%)(与基线比较,P〈0.001)。最严重病变10min节段斑块体积平均(SD)变化为-6.1(10.1)mm^3,中位数为-5.6mm^3(97.5%CI,-6.8~-4.0mm^3)(与基线比较,P〈0.001)。总斑块体积变化中位数降低了6.8%,平均减少了-14.7(25.7)mm^3,中位数为-12.5mm^3(95%CI,-15.1~-10.5mm^3)(与基线比较,P〈0.001)。不良事件少见,与其他他汀试验相似。
结论:应用瑞舒伐他汀40ms/d进行极高强度他汀治疗可使LDL-C平均水平达到60.8ms/dL,使HDL—C增加14.7%。这导致所有3个预先设定的IVUS斑块负荷指标均显示动脉粥样硬化消退。因此,将LDL-C降至低于目前指南规定的水平,同时显著提高HDL-C,可以使冠心病患者动脉粥样硬化斑块消退。这些变化对临床预后的影响尚需进一步研究确定。 | Steven E. Nissen Stephen J. Nicholls Ilks Sipahi Peter Libby Joel S. Raichlen Christie M. Ballantyne Jean Davignon Raimund Erbel Jean Charles Fruchart Jean-Claude Tardif Paul Schoenhagen Tim Crowe Valerie Cain Kathy Wolski Marlene Coormastic E. Murat Tuzcu 仝其广(译) 王淑敏(译) 胡大一(校) | 2006 | 美国医学会杂志(中文版)2006,25,4: | 341 |
| 2 | 从浅层建构走向深层建构——知识建构理论的发展及其在中国的应用分析显示文摘'知识建构'(Knowledge Building)理论是多伦多大学安大略教育研究院Marlene Scardamalia和Carl Bereiter两位教授于上世纪90年代提出的建构主义理论。在历经20多年的发展之后,其理论、教学法和技术手段已自成体系。知识建构理论认为:一般的建构主义教学以完成一系列任务和活动为导向,学生对为什么进行这些活动缺乏理解和掌控,属于'浅层'建构主义;而知识建构理论推崇的是'深层'建构,它以发展学习社区内的公共知识为目标,学生是积极的认知者,须共同承担认知责任。知识建构的基本观点被概括为12条基本原则,用作设计教学法和开发技术工具的基础。知识建构理论与实践已波及包括加拿大、美国、西班牙、新加坡和香港等18个国家和地区,涉及中小学科学、数学、社会、历史等多个学科教学,被应用到基础教育、高等教育、职业教育等多个领域。虽然知识建构理论前些年已由少数学者介绍到中国,但至今仍没有实质性的教学应用。究其原因,分科课程设置、大班教学和应试体制等现实条件是制约该理论在中国应用的主要因素。文章在介绍知识建构理论发展历史、基本原则和支撑技术的基础上,结合中国教育现状,探讨引进与应用该理论的策略,希望能对推进中国当前的课程改革、探讨新的教学思想与方法提供参考。 | 张义兵 陈伯栋 Marlene Scardamalia Carl Bereier | 2012 | 电化教育研究2012,33,9: | 74 |
| 3 | 知识建构共同体及其支撑环境显示文摘面对知识社会的挑战,我们需要将学校改造成为知识建构共同体。知识建构共同体是以思想的形成和持续改进为关注点的团体,其成员通过建构性的互动过程发展对于共同体有价值的思想。为了支持和促进知识建构共同体,本课题组研制了CSILE/知识论坛系统。本文对上述理论观点、技术系统以及有关的实验研究结果做了简要介绍。 | Marlene Scardamalia 张建伟 孙燕青 | 2005 | 现代教育技术2005,15,3: | 39 |
| 4 | Platelets and depression in cardiovascular disease:A brief review of the current literature显示文摘Major depression is an independent risk factor for cardiovascular mortality and morbidity. The exact mechanisms linking depression and increased cardiovascular risk remain poorly understood. Several mechanisms have been proposed including increased platelet reactivity. This review focuses on the current literature that examines the platelet hypothesis of depression. To date studies show increased serotonin response, increased platelet serotonin receptor density, decreased serotonin transporter binding, and decreased platelet serotonin levels in individuals with depression. However other studies have shown no change in serotonin uptake. In addition to platelet serotonin specific pathways, other platelet pathways that have shown significant changes in depressed individuals include blunting of the platelet adenosine response, increased platelet thrombin response, increased glycoprotein Ⅰb expression, increased P-selectin, β thromboglobulin, and platelet factor four, as well as decreased platelet brain derived neurotrophic factor. However there are other studies that show conflicting evidence of increased platelet activation as measured by integrin receptor α2b β3. Other conflictingdata include α adrenergic density and platelet response to augmented serotonin. The direction of future research in platelet functional changes in depression and coronary artery disease should continue to focus on serotonin specific pathways with emphasis on potential mechanisms of specific pathway changes. | Marlene S Williams | 2012 | World Journal of Psychiatry2012,2,6: | 21 |
| 5 | 限制热量摄入6个月对超重者寿命指标、代谢调节及氧化应激的影响——随机对照试验AuthorAffiliations:PenningtonBiomedicalResearchCenter.LouisianaStateUniversity.BatonRouge;andGarvan.InstituteforMedicalResearch.Dadinghurst,AustraIia(DrHeilbronn).显示文摘背景:长期限制热量摄入可延长啮齿类动物的寿命。但是,尚未有研究观测长期限制人体热量是否会影响其寿命及氧化应激指标,降低代谢率。
目的:在超重但不肥胖(体重指数为25—30)的人群中研究限制热量6个月伴/不伴运动对其产生的影响。
设计、地点及参试者:于2002年3月至2004年8月在位于路易斯安娜州首府巴顿鲁治的研究中心对48名不好动的健康人进行随机对照研究。
干预:参试者在6个月内随机分为4个组:对照组(饮食可维持体重);限制热量组(限制基线所需能量的25%);限制热量+运动组(限制12.5%的热量+运动增加12.5%的能耗);极低热量饮食组(每日摄入890keal,直至体重减少15%,随后采用维持体重的饮食)。
主要观测指标:机体组成;硫酸脱氢表雄酮(dehydroepiandrostemne sulfate,DHEAS)、葡萄糖及胰岛素水平;蛋白羰基化合物;DNA损伤;24小时能耗;核心体温。
结果:6个月时各组体重变化的均值(标准误)为:对照组-1.0%(1.1%);限制热量组-10.4%(0.9%);限制热量+运动组-10.0%(0.8%);极低热量饮食组-13.9%(0.7%)。6个月时,各干预组空腹血糖水平较基线明显降低(P均〈0.01),而DHEAS和葡萄糖水平没有改变。限制热量组及限制热量+运动组核心体温有所下降(P均〈0.05)。对机体组成进行校正后发现,对照组24小时静息能耗无变化,但限制热量组(-135kcal/d[42kcal/d])、限制热量+运动组(-117kcal/d[52kcal/d])和极低热量饮食组(-125kcal/d[35kcal/d])24小时静息能耗有所下降(P均〈0.008)。上述“代谢调节”(超出预计值的-6%)与对照组相比存在显著差异(P〈0.05)。6个月时,各组蛋白羰基化合物的浓度较基线时无变化,而各干预组DNA损伤有所减少(P〈0.005)。
结论:我们的研究结果显示,长期限制热量可降低人类寿命的2种指标(即空腹胰岛素水平和体温)。此外,我们的研究结果还支持下述理论,即限制热量能降低代谢率,且超过缩小代谢面积产生的相应效应。我们尚需开展远期研究来评价限制热量能否延缓人类衰老过程。 | Leonie K. Heibronn Lilian de Jonge Madlyn I. Frisard James P. DeLany D. Enette Larson-Meyer Jennifer Rood Tuong Nguyen Corby K. Martin Julia Volaufova Marlene M. Most Frank L. Greenway Steven R. Smith Walter A. Deutsch Donald A. Williamson Eric Ravussin 顾佳(译) | 2006 | 美国医学会杂志(中文版)2006,25,5: | 18 |
| 6 | Marking RNA:m^6A writers,readers,and functions in Arabidopsis显示文摘N^6-methyladenosine(m^6A)emerges as an important modification in eukaryotic mRNAs.m^6A has first been reported in 1974,and its functional significance in mammalian gene regulation and importance for proper development have been well established.An arsenal of writer,eraser,and reader proteins accomplish deposition,removal,and interpretation of the m^6A mark,resulting in dynamic function.This led to the concept of an epitranscriptome,the compendium of RNA species with chemical modification ofthe nucleobases in the cell,in analogy to the epigenome.While m^6A has long been known to also exist in plant mRNAs,proteins involved in m^6A metabolism have only recently been detected by mutant analysis,homology search,and mRNA interactome capture in the reference plant Arabidopsis thaliana.Dysregulation ofthe m^6A modification causes severe developmental abnormalities of leaves and roots and altered timing of reproductive development.Furthermore,m^6A modification affects viral infection.Here,we discuss recent progress in identifying m^6A sites transcriptome-wide,in identifying the molecular players involved in writing,removing,and reading the mark,and in assigning functions to this RNA modification in 4.thaliana.We highlight similarities and differences to m^6A modification in mammals and provide an outlook on important questions that remain to be addressed. | Marlene Reichel Tino Koster Dorothee Staiger | 2019 | Journal of Molecular Cell Biology2019,11,10: | 13 |
| 7 | Wound-Induced Shoot-to-Root Relocation of JA-Ile Precursors Coordinates Arabidopsis Growth显示文摘Multicellular organisms rely on the movement of signaling molecules across cells,tissues,and organs to communicate among distal sites.In plants,localized leaf damage activates jasmonic acid(JA)-dependent transcriptional reprogramming in both harmed and unharmed tissues.Although it has been indicated that JA species can translocate from damaged into distal sites,the identity of the mobile compound(s),the tissues through which they translocate,and the effect of their relocation remain unknown.Here,we found that following shoot wounding,the relocation of endogenous jasmonates through the phloem is essential to initiate JA signaling and stunt growth in unharmed roots of Arabidopsis thaliana.By employing grafting experiments and hormone profiling,we uncovered that the hormone precursor cis-12-oxo-phytodienoic acid(OPDA)and its derivatives,but not the bioactive JA-Ile conjugate,translocate from wounded shoots into undamaged roots.Upon root relocation,the mobile precursors cooperatively regulated JA responses through their conversion into JA-Ile and JA signaling activation.Collectively,our findings demonstrate the existence of long-distance translocation of endogenous OPDA and its derivatives,which serve as mobile molecules to coordinate shoot-to-root responses,and highlight the importance of a controlled redistribution of hormone precursors among organs during plant stress acclimation. | Adina Schulze Marlene Zimmer Stefan Mielke Hagen Stellmach Charles WMelnyk Bettina Hause Debora Gasperini | 2019 | Molecular Plant2019,12,10: | 7 |
| 8 | 中国“一带一路”与哈萨克斯坦“光明之路”对接合作的研究显示文摘由于全球石油价格暴跌、俄罗斯的经济低迷以及卢布的后续崩溃严重影响了哈国国民经济,为振兴国民经济,2014年11月哈萨克斯坦总统纳扎尔巴耶夫在其年度国情咨文中提出了"光明之路——通往未来之路"的新经济计划,旨在强力推动经济增长,使收入来源多样化,并降低哈萨克斯坦对能源出口收入的依赖程度。 | 严双伍 Marlen Belgibayev | 2016 | 国际经济合作2016,,6: | 7 |
| 9 | A tale of worldwide success:Behind the scenes of Carex(Cyperaceae)biogeography and diversification显示文摘The megadiverse genus Carex(c.2000 species,Cyperaceae)has a nearly cosmopolitan distribution,displaying an inverted latitudinal richness gradient with higher species diversity in cold-temperate areas of the Northern Hemisphere.Despite great expansion in our knowledge of the phylogenetic history of the genus and many molecular studies focusing on the biogeography of particular groups during the last few decades,a global analysis of Carex biogeography and diversification is still lacking.For this purpose,we built the hitherto most comprehensive Carex-dated phylogeny based on three markers(ETS-ITS-matK),using a previous phylogenomic Hyb-Seq framework,and a sampling of two-thirds of its species and all recognized sections.Ancestral area reconstaiction,biogeographic stochastic mapping,and diversification rate analyses were conducted to elucidate macroevolutionary biogeographic and diversification patterns.Our results reveal that Carex originated in the late Eocene in E Asia,where it probably remained until the synchronous diversification of its main subgeneric lineages during the late Oligocene.E Asia is supported as the cradle of Carex diversification,as well as a< | Santiago Martin-Bravo Pedro Jimenez-Mejias Tamara Villaverde Marcial Escudero Marlene Hahn Daniel Spalink Eric H.Roalson Andrew L.Hipp the Global Carex Group Carmen Benitez-Benitez Leo P.Bruederle Elisabeth Fitzek Bruce A.Ford Kerry A.Ford Mira Gamer Sebastian Gebauer Matthias H.Hoffmann Xiao-Feng Jin Isabel Larridon Etienne Ldveilld-Bourret Yi-Fei Lu Modesto Luceno Enrique Maguilla Jose Ignacio Marquez-Corro Monica Miguez Robert Naczi Anton A.Reznicek Julian R.Starr | 2019 | Journal of Systematics and Evolution2019,57,6: | 6 |
| 10 | A Re‐examination of Disclosure Level and the Expected Cost of Equity Capital显示文摘 | Christine A.Botosan Marlene A.Plumlee | 2002 | Journal of Accounting Research2002,,1: | 5 |
| 11 | NH_3 Plasma Surface Treatments of Engineering Fluoropolymers: A Way to Enhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating显示文摘This paper describes the electroless Ni or Cu plating of some fiuoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon() FEP, Nafion(), ACLAR() and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i)the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion in a simple acidic PdCl2 solution (i.e. without using a prior surface sensitization in an acidic SnCl2 solution), and finally (iii) the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+2 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (PdO) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters. | Maurice Romand Marlene Charbonnier Yves Goepfert | 2004 | 材料热处理学报2004,25,05B: | 5 |
| 12 | Current approach to treatment of minimal hepatic encephalopathy in patients with liver cirrhosis显示文摘Minimal hepatic encephalopathy(MHE)corresponds to the earliest stage of hepatic encephalopathy(HE).MHE does not present clinically detectable neurological-psychiatric abnormalities but is characterized by imperceptible neurocognitive alterations detected during routine clinical examination via neuropsychological or psychometrical tests.MHE may affect daily activities and reduce job performance and quality of life.MHE can increase the risk of accidents and may develop into overt encephalopathy,worsening the prognosis of patients with liver cirrhosis.Despite a lack of consensus on the therapeutic indication,interest in finding novel strategies for prevention or reversion has led to numerous clinical trials;their results are the main objective of this review.Many studies address the treatment of MHE,which is mainly based on the strategies and previous management of overt HE.Current alternatives for the management of MHE include measures to maintain nutritional status while avoiding sarcopenia,and manipulation of intestinal microbiota with non-absorbable disaccharides such as lactulose,antibiotics such as rifaximin,and administration of different probiotics.This review analyzes the results of clinical studies that evaluated the effects of different treatments for MHE. | Segundo Moran Marlene López-Sánchez María del Pilar Milke-García Gustavo Rodríguez-Leal | 2021 | World Journal of Gastroenterology2021,27,22: | 5 |
| 13 | Role of ATG16L,NOD2 and IL23R in Crohn's disease pathogenesis显示文摘Inflammatory bowel disease is a group of diseases that includes Crohn's disease (CD) and ulcerative colitis.CD is characterized as a chronic inflammatory disease of the gastrointestinal tract,ranging from the mouth to the anus.Although there are gross pathological and histological similarities between CD and Johne's disease of cattle,the cause of CD remains controversial.It is vital to understand fully the cause of this disease because it affects approximately 500 000 people in North America and Europe.It ranges from 27 to 48 cases per 100 000 people.There are many theories on the cause of CD ranging from possible association with environmental factors including microorganisms to imbalance in the intestinal normal flora of the patients.Regardless of the environmental trigger,there is strong evidence that a genetic disposition is a major key in acquiring CD.Many studies have proven the link between mutations in the ATG16L,NOD2/CARD15,IBD5,CTLA4,TNFSF15 and IL23R genes,and CD.The purpose of this review is to examine all genetic aspects and theories of CD,including up to date multiple population studies performed worldwide. | Saleh A Naser Melissa Arce Anam Khaja Marlene Fernandez Najih Naser Sammer Elwasila Saisathya Thanigachalam | 2012 | World Journal of Gastroenterology2012,18,5: | 5 |
| 14 | An integrated suspended sediment transport monitoring and analysis concept显示文摘A new integrated suspended sediment monitoring strategy applying direct and indirect technologies is presented.Optical sensors continuously record the turbidity at one point in the channel cross section close to the river bank and are calibrated by water samples taken close to the sensor.Additionally measurements are performed to establish the distribution of suspended sediment in a cross section(bottle samples combined with acoustic devices).Using correction factors(probe and cross-sectional factor) these monitoring methods are combined and it is,thus,possible to fully document the temporal and spatial variability of the suspended sediment transport and to estimate the suspended sediment load for certain time periods.This monitoring strategy was implemented at various measurement sites in Austria as well as at the Hainburg Road Bridge site on the Danube River.It has already been successfully applied for three years at this measurement site and suspended sediment loads during high discharges up to a 15 year flood event have been monitored.To evaluate the new monitoring methods the results were compared with load estimation methods found in the literature including averaging and ratio estimators as well as rating curves.The results prove that with the new methodology,the temporal variability of the suspended sediment transport can be detected more accurately compared with the other methods.They also demonstrate that the additional consideration of the spatial distribution of the suspended sediment concentration in the cross section is crucial as the mean concentration in the cross section can significantly exceed the concentration near the banks,especially at large rivers like the Danube River. | Marlene HAIMANN Marcel LIEDERMANN Petra LALK Helmut HABERSACK | 2014 | International Journal of Sediment Research2014,29,2: | 4 |
| 15 | Monograph of Carex section Schiedeanae (Cyperaceae): Unexpected taxonomic and ecological diversity in a Mexican sedge clade显示文摘Carex section Schiedeanae(subg.Euthyceras)has long been thought to comprise at most five species of Mexican sedges.Our morphological studies in the field and herbarium,however,supported by more recent DNA sequencing work,demonstrate that the section is,in fact,three times as species-rich,making it one of the largest sections in Mexico.Its 15 species range from Chihuahua to Tamaulipas south to Veracruz and Oaxaca;a single species,Carex muriculata,extends into the United States.The section has unusual inflorescences with simple(except in Carex complexa),uniformly androgynous,sessile spikes,utriculiform dadoprophylls,and perigynia with a unique combination of pubescence types composed of papillae;unicellular,simple hairs;and(in many species)multicellular tubercles.We recognize five previously described species(C.muriculata,Carex perstricta,Carex schiedeana,Carex stellata,and Carex vizarronensis)and describe 10 additional species(Carex angustilepis,Carex cabralii,Carex complexa,Carex dentata,Carex gypsophila,Carex mesophila,Carex paneroi,Carex planilamina,Carex revoluta,and Carex tehuacana).We have expanded the morphological features used in the section to include particularly anther,staminate scale,and style features,and more detailed micromorphology of the perigynia,especially indumentum.In total,13 of the 15 species recognized herein,with a total of 32 individuals,were examined for ETS and ITS for phylogenetic reconstruction.Phylogenetically,the xeric species(plus C.paneroi)form a grade leading to a clade of the more mesophytic species adapted to forest understories,plus the unique cliff dwelling C.complexa. | Anton A.Reznicek Maria del Socorro Gonzalez-Elizondo Marlene Hahn Mira Gamer Andrew L.Hipp | 2021 | Journal of Systematics and Evolution2021,59,4: | 4 |
| 16 | 对中国基础通货膨胀指标的研究显示文摘对于货币政策决策者和市场参与者来说,通货膨胀都是个关键的宏观经济变量。论文建立了一个新的中国基础通货膨胀度量指标(CUIG),可以区分趋势和噪声,可以按日计算,而且使用了可能影响通货膨胀的大量经济变量。该指标的构造方法以Forni等人2000年的动态因子模型研究成果为基础,并已经在纽约联储和瑞士央行进行了成功的运用。和CPI相比,这个指标更平滑,但也不像传统核心通胀指标那样去除了过多波动性。这个指标能紧密追踪CPI,同时能提供传统核心通胀指标不包含的额外信息。最后,预测统计检验证明这个指标在不同的样本区间对CPI的预测表现都好于传统核心通胀指标。 | Marlene Amstad 叶欢 马国南 | 2015 | 财务与金融2015,,5: | 3 |
| 17 | Levels and trends of poly-and perfluoroalkyl substances in the Arctic environment-An update显示文摘Poly-and perfluoroalkyl substances(PFASs)are important environmental contaminants globally and in the early 2000s they were shown to be ubiquitous contaminants in Arctic wildlife.Previous reviews by Butt et al.and Letcher et al.have covered studies on levels and trends of PFASs in the Arctic that were available to 2009.The purpose of this review is to focus on more recent work,generally published between 2009 and 2018,with emphasis on PFASs of emerging concern such as perfluoroalkyl carboxylates(PFCAs)and short-chain perfluoroalkyl sulfonates(PFSAs)and their precursors.Atmospheric measurements over the period 2006e2014 have shown that fluorotelomer alcohols(FTOHs)as well as perfluorobutanoic acid(PFBA)and perfluoroctanoic acid(PFOA)are the most prominent PFASs in the arctic atmosphere,all with increasing concentrations at Alert although PFOA concentrations declined at the Zeppelin Station(Svalbard).Results from ice cores show generally increasing deposition of PFCAs on the Devon Ice cap in the Canadian arctic while declining fluxes were found in a glacier on Svalbard.An extensive dataset exists for long-term trends of long-chain PFCAs that have been reported in Arctic biota with some datasets including archived samples from the 1970s and 1980s.Trends in PFCAs over time vary among the same species across the North American Arctic,East and West Greenland,and Svalbard.Most long term time series show a decline from higher concentrations in the early 2000s.However there have been recent(post 2010)increasing trends of PFCAs in ringed seals in the Canadian Arctic,East Greenland polar bears and in arctic foxes in Svalbard.Annual biological sampling is helping to determine these relatively short term changes.Rising levels of some PFCAs have been explained by continued emissions of long-chain PFCAs and/or their precursors and inflows to the Arctic Ocean,especially from the North Atlantic.While the effectiveness of biological sampling for temporal trends in long-chain PFCAs and PFSAs has been demonstrated,this does not apply to the C4eC8ePFCAs,perfluorobutane sulfonamide(FBSA),or perfluorobutane sulfonate(PFBS)which are generally present at low concentrations in biota.In addition to air sampling,sampling abiotic media such as glacial cores,and annual sampling of lake waters and seawater would appear to be the best approaches for investigating trends in the less bioaccumulative PFASs. | Derek Muir Rossana Bossi Pernilla Carlsson Marlene Evans Amila De Silva Crispin Halsall Cassandra Rauert Dorte Herzke Hayley Hung Robert Letcher Frank Riget Anna Roos | 2019 | Emerging Contaminants2019,5,1: | 3 |
| 18 | Adsorption of pharmaceuticals from aqueous solutions using biochar derived from cotton gin waste and guayule bagasse显示文摘Biochars produced from cotton gin waste(CG)and guayule bagasse(GB)were characterized and explored as potential adsorbents for the removal of pharmaceuticals(sulfapyridine-SPY,docusate-DCT and erythromycin-ETM)from aqueous solution.An increase in biochar pyrolysis temperature from 350οC to 700℃ led to an increase in pH,specific surface area,and surface hydrophobicity.The electronegative surface of all tested biochars indicated that non-Coulombic mechanisms were involved in adsorption of the anionic or uncharged pharmaceuticals under experimental conditions.The adsorption capacities of Sulfapyridine(SPY),Docusate(DCT)and Erythromycin(ETM)on biochar were influenced by the contact time and solution pH,as well as biochar specific surface area and functional groups.Adsorption of these pharmaceutical compounds was dominated by a complex interplay of three mechanisms:hydrophobic partitioning,hydrogen bonding andπ-πelectron donor-acceptor(EDA)interactions.Despite weakerπ-πEDA interactions,reduced hydrophobicity of SPY−and increased electrostatic repulsion between anionic SPY−and the electronegative CG biochar surface at higher pH,the adsorption of SPY unexpectedly increased from 40% to 70% with an increase in pH from 7 to 10.Under alkaline conditions,adsorption was dominated by the formation of strong negative charge-assisted H-bonding between the sulfonamide moiety of SPY and surface carboxylic groups.There seemed to be no appreciable and consistent differences in the extent of DCT and ETM adsorption as the pH changed.Results suggest the CG and GB biochars could act as effective adsorbents for the removal of pharmaceuticals from reclaimed water prior to irrigation.High surface area biochars with physico-chemical properties(e.g.,presence of functional groups,high cation and anion exchange capacities)conducive to strong interactions with polar-nonpolar functionality of pharmaceuticals could be used to achieve significant contaminant removal from water. | Marlene C.Ndoun Herschel AElliott Heather EPreisendanz Clinton FWilliams Allan Knopf John EWatson | 2021 | Biochar2021,3,1: | 3 |
| 19 | A framework infrageneric classification of Carex (Cyperaceae) and its organizing principles显示文摘Phylogenetic studies of Carex L.(Cyperaceae)have consistently demonstrated that most subgenera and sections are para-or polyphyletic.Yet,taxonomists continue to use subgenera and sections in Carex classification.Why?The Global Carex Group(GCG)here takes the position that the historical and continued use of subgenera and sections serves to(i)organize our understanding of lineages in Carex,(ii)create an identification mechanism to break the~2000 species of Carex into manageable groups and stimulate its study,and(iii)provide a framework to recognize morphologically diagnosable lineages within Carex.Unfortunately,the current understanding of phylogenetic relationships in Carex is not yet sufficient for a global reclassification of the genus within a Linnean infrageneric(sectional)framework.Rather than leaving Carex classification in its current state,which is misleading and confusing,we here take the intermediate steps of implementing the recently revised subgeneric classification and using a combination of informally named clades and formally named sections to reflect the current state of our knowledge.This hybrid classification framework is presented in an order corresponding to a linear arrangement of the clades on a ladderized phylogeny,largely based on the recent phylogenies published by the GCG.It organizes Carex into six subgenera,which are,in turn,subdivided into 62 formally named Linnean sections plus 49 informal groups.This framework will serve as a roadmap for research on Carex phylogeny,enabling further development of a complete reclassification by presenting relevant morphological and geographical information on clades where possible and standardizing the use of formal sectional names. | Eric H.Roalson Pedro Jiménez-Mejías Andrew L.Hipp Carmen Benítez-Benítez Leo P.Bruederle Kyong-Sook Chung Marcial Escudero Bruce A.Ford Kerry Ford Sebastian Gebauer Berit Gehrke Marlene Hahn Muhammad Qasim Hayat Mathias H.Hoffmann Xiao-Feng Jin Sangtae Kim Isabel Larridon Étienne Léveillé-Bourret Yi-Fei Lu Modesto Luceño Enrique Maguilla Jose IgnacioMárquez-Corro Santiago Martín-Bravo Tomomi Masaki Mónica Míguez Robert F.C.Naczi Anton A.Reznicek Daniel Spalink Julian R.Starr Uzma Tamara Villaverde Marcia J.Waterway Karen L.Wilson and Shu-Ren Zhang | 2021 | Journal of Systematics and Evolution2021,59,4: | 3 |
| 20 | Trait evolution rates shape continental patterns of species richness in North America's most diverse angiosperm genus (Carex, Cyperaceae)显示文摘Ecological opportunity has been associated with increases in diversification rates across the tree of life.Under an ecological diversification model,the emergence of novel environments is hypothesized to promote morpho-and ecospace evolution.Whether this model holds at the clade level within the most species-rich angiosperm genus found in North America(Carex,Cyperaceae)is yet to be tested.Recent works demonstrate a temporal coupling of climate cooling and widespread colonization of Carex in North America,implicating ecological diversification.In addition,research has consistently found asymmetric patterns of lineage-level diversification in the genus.Why does variation in clade sizes exist in the genus?Is ecological diversification involved?In this study,we tested whether rates of morphological and ecological trait evolution are correlated with clade-level species richness in Carex of North America north of Mexico.We constructed a phylogeny of 477 species-an almost complete regional sample.We estimated rates of evolution of morphological traits,habitat,and climatic niche and assessed whether differences in rates of evolution correlate with species richness differences in replicate non-nested sister clades.Our work demonstrates significant positive correlations between climatic niche rates,habitat and reproductive morphological evolution,and species richness.This coupling of trait and niche evolution and species richness in a diverse,continental clade sample strongly suggests that the ability of clades to explore niche and functional space has shaped disparities in richness and functional diversity across the North American flora region.Our findings highlight the importance of the evolutionary history of trait and niche evolution in shaping continental and regional floras. | Jocelyn E.Pender Andrew L.Hipp Marlene Hahn Julian R.Starr | 2021 | Journal of Systematics and Evolution2021,59,4: | 3 |