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Principles for managing marine ecosystems prone to tipping points

Ecosystem Health and Sustainability 2015年第5期1卷 15-32页

作者： Kimberly A.Selkoe Thorsten Blenckner Margaret R.Caldwell Larry B.Crowder Ashley L.Erickson Timothy E.Essington James A.Estes Rod M.fujita Benjamin S.Halpern Mary E.Hunsicker Carrie V.Kappel Ryan P.Kelly john N.Kittinger Phillip S.Levin john M.Lynham Megan E.Mach Rebecca g.Martone Lindley A.Mease Anne KSalomon Jameal f.Samhouri Courtney Scarborough Adrian C.Stier Crow White Joy Zedler National Center for Ecological Analysis and Synthesis 735 State StreetSuite 300Santa BarbaraCalifornia 93101 USA Hawaii Institute of Marine Biology University of HawaiiKaneoheHawaii 96744 USA Stockholm Resilience Centre Stockholm UniversityKra¨ftriket 2B10691 StockholmSweden Center for Ocean Solutions Stanford Woods Institute for the EnvironmentStanford University473 Via Ortega Room 193StanfordCalifornia 94305 USA School of Aquatic and fishery Sciences University of WashingtonSeattleWashington 98195 USA Department of Ecology and Evolutionary Biology 100 Shaffer RoadUniversity of CaliforniaSanta CruzCalifornia 95060 USA Environmental Defense fund 123 Mission Street28th FloorSan FranciscoCalifornia 94105 USA Bren School of Environmental Science and Management University of CaliforniaSanta BarbaraCalifornia 93106 USA Imperial College London Silwood Park CampusBuckhurst RoadAscot SL57PY United Kingdom School of Marine and Environmental Affairs University of Washington3707 Brooklyn Avenue NESeattleWashington 98105-6715 USA Conservation International Betty and Gordon Moore Center for Science and Oceans7192 Kalaniana‘ole HighwaySuite G230HonoluluHawaii 96825 USA Conservation Biology Division Northwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric Administration2725 Montlake Boulevard EastSeattleWashington 98112 USA Department of Economics University of Hawaii at ManoaHonoluluHawaii 96822 USA School of Resource and Environmental Management Simon Fraser UniversityBurnabyBritish Columbia V5A1S6 Canada Department of Biological Sciences California Polytechnic State UniversitySan Luis ObispoCalifornia 93407 USA Botany Department University of WisconsinMadisonWisconsin 53706 USA

As climatic changes and human uses intensify,resource managers and other decision makers are taking actions to either avoid or respond to ecosystem tipping points,or dramatic shifts in structure and function that are often costly and hard to *** indicates that explicitly addressing tipping points leads to improved management *** on theory and examples from marine systems,we distill a set of seven principles to guide effective management in ecosystems with tipping points,derived from the best available *** principles are based on observations that tipping points(1)are possible everywhere,(2)are associated with intense and/or multifaceted human use,(3)may be preceded by changes in earlywarning indicators,(4)may redistribute benefits among stakeholders,(5)affect the relative costs of action and inaction,(6)suggest biologically informed management targets,and(7)often require an adaptive response to *** suggest that early action to preserve system resilience is likely more practical,affordable,and effective than late action to halt or reverse a tipping *** articulate a conceptual approach to management focused on linking management targets to thresholds,tracking early-warning signals of ecosystem instability,and stepping up investment in monitoring and mitigation as the likelihood of dramatic ecosystem change *** approach can simplify and economize management by allowing decision makers to capitalize on the increasing value of precise information about threshold relationships when a system is closer to tipping or by ensuring that restoration effort is sufficient to tip a system into the desired regime.

关键词： critical transition ecosystem-based management marine spatial planning nonlinear relationships restoration ecology stakeholder engagement

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Cu3Ti原子簇结构与光谱的密度泛函理论研究

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光谱学与光谱分析 2008年第7期28卷 1488-1491页

作者：魏永慧程建波赵冰 Lombardi john R 北华大学化学与生物学院吉林吉林市132013 吉林大学超分子结构与材料国家重点实验室吉林长春130012 烟台大学化学生物理工学院山东烟台264005 美国纽约市立大学化学系纽约10031

异核金属合金是非常重要的材料,Cu3Ti具有形状记忆、高强度和声音吸收特性。由于实验中只观察到一条拉曼谱线,但其稳定结构并不清晰。文章利用密度泛函理论中的SVWN5,B3LYP和BPW91方法,分别采用lanl2dz,6-31g,6-311g,6-311g(d),6-311+g(... 详细信息

异核金属合金是非常重要的材料,Cu3Ti具有形状记忆、高强度和声音吸收特性。由于实验中只观察到一条拉曼谱线,但其稳定结构并不清晰。文章利用密度泛函理论中的SVWN5,B3LYP和BPW91方法,分别采用lanl2dz,6-31g,6-311g,6-311g(d),6-311+g(2df)和6-311+g(3d2f)基组对Cu3Ti多种可能的结构和振动光谱进行了研究。结合实验结果分析,表明其基态为自旋多重度为4的e型C2v对称性结构,基组对于频率和原子间距的影响比较大;并与实验拉曼光谱进行了对比。

关键词： Cu3Ti DfT 原子簇分子结构振动光谱

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OH+C2H3f的反应机理及产物支化比反应的理论研究（英文）

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Chinese Journal of Chemical Physics 2020年第2期 203-223页

作者： Chih-Hao Chin Tong Zhu john Zeng-Hui Zhang 华东师范大学化学与分子工程学院上海纽约大学计算化学联合中心美国纽约大学化学系

木文对HOC2H3f可能解离通道的势能面进行从头算CCSD（T）/CBS//B3LYP/6-311g（d,p）计算,同时对速率常数进行Rice-Ra msperger-Kassel-Marcus计算.生成主要产物CH2CHO+Hf最有利的反应途径是OHC2H3f→i2→TS14→i6→TS9→i3→TS3→CH2C HO+Hf,其中速率决定步骤是Hf通过TS11从CO桥接位置解离,能量比反应物高3.8 kcal/mol.借助中间态TS14,f原子从Cβ迁移到Cα位置生成CH2O+CH2f,然后通过中间态TS16,H从O迁移到Cα位置;通过中间态TS5,C-C键断裂生成产物,其能量比反应物低1.8 kcal/mol,比TS11低4.0 kcal/mol.

关键词：从头算势能面反应机理 Rice-Ramsperger-Kassel-Marcus 产物分支比

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OH+C2H3f的反应机理及产物支化比反应的理论研究

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Chinese Journal of Chemical Physics 2020年第2期33卷 203-209,I0003页

作者： Chih-Hao Chin Tong Zhu john Zeng-Hui Zhang 华东师范大学化学与分子工程学院上海200062 上海纽约大学计算化学联合中心上海200062 美国纽约大学化学系纽约10003

本文对HOC2H3f可能解离通道的势能面进行从头算CCSD(T)/CBS//B3LYP/6-311g(d,p)计算,同时对速率常数进行Rice-Ramsperger-Kassel-Marcus计算.生成主要产物CH2CHO+Hf最有利的反应途径是OHC2H3f→i2→TS14→i6→TS9→i3→TS3→CH2CHO+Hf,其中速率决定步骤是Hf通过TS11从CO桥接位置解离,能量比反应物高3.8 kcal/mol.借助中间态TS14,f原子从Cα迁移到Cβ位置生成CH2O+CH2f,然后通过中间态TS16,H从O迁移到Cα位置;通过中间态TS5,C-C键断裂生成产物,其能量比反应物低1.8 kcal/mol,比TS11低4.0 kcal/mol.

关键词：从头算势能面反应机理 Rice-Ramsperger-Kassel-Marcus 产物分支比

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growth dynamics of individual clones of normal human keratinocytes: observations and theoretical considerations

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Natural Science 2011年第8期3卷 702-722页

作者： john J Wille 不详

The life histories of 429 individual epidermal keratinocyte clones picked at random were studied. Individual basal keratinocytes were derived from asynchronous rapidly proliferating subconfluent cultures propagated in either a low calcium (0.1mM) or a high calcium (2mM) serum-free medium. Single-celled clones were isolated by seeding trypsin-EDTA dissociated cells into a Petri dish containing cloning chips. Chips with only one cell per chip were transferred into dishes containing either low calcium or high calcium growth factor replete serum-free medium. Clone formation was monitored microscopically and the number of cells in each colony tallied at least twice daily for further analysis. A total of 369 clones were established from seven different neonatal foreskin cell strains (A-f), and 60 clones were derived from one adult human skin cell strain (g). During a five-day culture interval, among 32 clones of strain A, 83% divided at least once, 50% divided once in 24 hours, 86% divided at least three times within three days, and more than 50% divided at least four to five times in five days. Of 231 clones amongst the other five cell strains (B-f), an average of 63% (±12 S,E) divided more than three times in an eight day period, the remainder divided either once, twice or not at all. Of the 106 clones of strain g, reared in high calcium serum-free medium, 67% divided more than three times in a six-day period, and 55% divided five or more times in 6 days. Clones derived from adult skin strain H had a lower clone forming potential with 70% dividing at least once in seven days, and only 30% dividing three or more times. By contrast, the average generation time (AvgT) for second and third passage keratinocytes derived from neonatal foreskin cultures was 24 hrs. Detailed dendrograms were constructed for many of the proliferating clones. The majority of clones expressed a synblastic division pattern with every cell dividing at least once per day. A fraction of clones either

关键词： Biochemical Oscillators Clonal growth Dynamics Human Keratinocytes INTERDIVISION Times Temporal Control of Mitosis Models

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Problems in the Language form and function Debate and a Way forward

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Language and Semiotic Studies 2015年第4期1卷 19-33页

作者： john A.Hawkins University of California Davis USA Cambridge University

A much debated issue in linguistics involves the extent to which the forms of languages(phonemes,morphemes,words,phrases and syntactic structures)have been shaped by the functions that languages *** paper begins by defining what these"functions"are:the forms of language must express(*** capable of being paired with)an infinite set of meanings in a consistent way;these form-meaning pairings must be readily processable by language producers and comprehenders in real time;and they must be readily *** paper then focuses on the processability function,and enumerates some problems that complicate discussions of whether processing has actually played a role in shaping grammars,especially in morphology and *** of these problems,it is argued,are the result of unresolved issues in current theories regarding *** precise relationship between production and comprehension,the measurement of working memory load,and the relationship between prediction and the integration of preceding and following items in on-line processing.I argue here that the linguistic question of explaining why the world’s grammars are the way they are,and understanding the role of processing in explaining grammatical forms,need not,and cannot,wait for these big general issues to be resolved in ***,we can adopt a more empirical approach that compares patterns in grammatical forms and structures across languages with relevant empirical patterns in usage data within languages,from corpora and *** more empirical approach allows us to test whether there is,or is not,a match between grammatical data on the one hand,and usage data on the other,that are the products of the processing mechanisms that psycholinguistic theories are trying to def *** patterns can be described in theory-general or-neutral ways and they can shed light on whether grammatical forms have been shaped by performance,without us having to f ill in all the details of the

关键词： efficiency form-function correspondences functions of language head ordering hierarchies language processing Minimize Domains Minimize forms Performancegrammar Correspondence Hypothesis

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Profiles of energy metabolites and haptoglobin in dairy cows under organic management in Alberta farms

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Open Journal of Animal Sciences 2013年第2期3卷 105-113页

作者： john f. Odhiambo Umar farooq Summera Iqbal Dominik Mansmann Qendrim Zebeli Suzanna M. Dunn Burim N. Ametaj Department of Agricultural Food and Nutritional Science University of Alberta Edmonton Canada Department of Animal Science University of Wyoming Laramie USA Institute of Animal Nutrition Department for Farm Animals and Veterinary Public Health University of Veterinary Medicine Vienna Austria

Profiles of energy metabolites and haptoglobin (Hp) in dairy cows that are transitioned from conventional to organic management in various Alberta farms were compared with those of dairy cows managed conventionally at the University of Alberta dairy farm. Blood samples were collected during the following periods: Dry, 0 - 30, 30 - 60, and 60 - 90 days in milk (DIM, n = 7 cows). Concentrations of metabolites were evaluated by enzymatic colorimetric methods. Concentrations of Hp were determined by bovine ELISA kits. Data were analyzed by the mixed procedures of SAS. Concentrations of NEfA and BHBA in blood were elevated (P gher (P ges of lactation in conventional than organic cows (e.g. 1289.4 ± 88.6 vs. 883.6 ± 47.5 μmol/L in conventional and organic cows at 0 - 30 d, respectively). Serum concentrations of cholesterol increased with increasing DIM and returned to nadir levels during dry period and was higher (P ganic cows. Low glucose concentrations were observed 0 to 30 d, levels were intermediate 30 to 60 and 60 to 90 d, and peaked during the dry period (P ganic cows. Lactate did not (P farm type but was higher (P ganic cows than in conventional cows. Serum concentrations of Hp were elevated during dry period;reached peak levels 0 to 30 d and decreased gradually with increasing days postpartum and were much higher at all periods in conventional than organic cows. Overall, concentrations of Hp were 528.1 ± 45.2 μg/mL in conventional cows vs. 261.1 ± 16.9 μg/mL in organic cows (P gether, these data indicate that metabolic changes associated with initiation of lactation are preceded by an acute phase response in dairy cows, and that cows in organic systems seem to be healthier than cows under conventional sy

关键词： Organic Cows BHBA NEfA Haptoglobin

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Preface to the Special Issue on Antarctic Meteorology and Climate:Past,Present and future

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Advances in Atmospheric Sciences 2020年第5期37卷 421-422页

作者： Jiping LIU David BROMWICH Dake CHEN Raul CORDERO Thomas JUNg Marilyn RAPHAEL john TURNER Qinghua YANg Department of Atmospheric and Environmental Sciences University at AlbanyState University of New YorkAlbanyNY 12222USA Polar Meteorology group Byrd Polar and Climate Research CenterThe Ohio State UniversityColumbusOH 43210USA State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyHangzhou 310012China Southern Marine Science and Engineering guangdong Laboratory(Zhuhai) Zhuhai 519082China Departamento de física University of SantiagoSantiago 3493Chile Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchBremerhaven 27570Germany Institute of Environmental Physics University of BremenBremen 28359Germany Department of geography University of California-Los AngelesLos AngelesCA 90095USA British Antarctic Survey Natural Environment Research CouncilCambridgeCB30ETUK School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China

The Antarctic,including the continent of Antarctica and the Southern Ocean,is a critically important part of the Earth *** in Antarctic meteorology and climate has always been a challenging *** and predicting weather patterns in the Antarctic are important for understanding their role in local-to-global processes and facilitating field studies and logistical operations in the Antarctic(e.g.,Walsh et al.,2018).Studies of climate change in the Antarctic are comparatively neglected compared to those of the ***,significant climate changes have occurred in the Antarctic in the past several decades,i.e.,a strong warming over the Antarctic Peninsula even with a recent minor cooling,a deepening of the Amundsen Sea low,a rapid warming of the upper ocean north of the circumpolar current,an increase of Antarctic sea ice since the late 1970s followed by a recent rapid decrease,and an accelerated ice loss from the Antarctic ice shelf/sheet since the late 1970s(e.g.,Turner et al.,2005;Raphael et al.,2016;Sallée,2018;Parkinson,2019;Rignot et al.,2019).Investigating recent climate change in the Antarctic and the underlying mechanisms are important for predicting future climate change and providing information to policymakers.

关键词： Antarctic warming meteorology

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增加β-乳球蛋白和乳清蛋白质含量对UHT奶保存稳定性的影响

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乳业科学与技术 2000年第4期23卷 16-22页

作者： john f.Hardham 宋晓梅张少辉

本试验检测了在UHT牛奶中添加浓缩β-乳球蛋白粉(0.015-0.375g/100g牛奶)或乳清粉(0.26-2.5g/100g牛奶)对其稳定保存的影响。在生奶中添加β-乳球蛋白或乳清粉,增加乳清蛋白质的浓度,UHT奶推迟了凝结时间。添加低浓度的β-乳球蛋白通常... 详细信息

本试验检测了在UHT牛奶中添加浓缩β-乳球蛋白粉(0.015-0.375g/100g牛奶)或乳清粉(0.26-2.5g/100g牛奶)对其稳定保存的影响。在生奶中添加β-乳球蛋白或乳清粉,增加乳清蛋白质的浓度,UHT奶推迟了凝结时间。添加低浓度的β-乳球蛋白通常推迟凝结时间4-8周,而大剂量的添加β-乳球蛋白或乳清粉将进一步推迟凝结时间。凝结出现在样品上层的乳脂层,通常与样品凝结有关的粘度并没有增加。牛奶组成的季节变化与凝结时间之间没有明显相关。

关键词： UHT奶 β-乳球蛋白乳清蛋白质保存稳定性

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Compliance and Tolerance of a New High Protein and High Energy Oral Nutritional Supplement in Older Adults

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Journal of Nutritional Oncology 2018年第3期3卷 120-129页

作者： Cornelius Koch Annika Dax Andre Warnke Lioba Pauly Stephanie Reichart Katharina S.Kuhn Ericka A Pestana john f Stover Konstantin Lekkos SocraTec R&D gmbH ErfurtGermany fresenius Kabi Deutschland gmbH Bad HomburgGermany Medical Writing StuttgartGermany Helios Klinikum HildesheimDepartment of GeriatricsGermany

Background and objectives Volume,caloric density,and timing of administration influence compliance to oral nutritional supplements(ONS).The provision of high energy,high protein and low volume ONS may allow easy achievement of intakes considered effective in improving nutritional *** report the evaluation of a new low volume,energy dense ONS in older *** and study design Two open-label studies,each including 20 older adults(75±4 and 76±5 years)in residential *** received one bottle(125 ml,400 kcal,20 g protein)of the new ONS daily,either as a single or multiple dose(3×40 ml/~400 kcal)for 7 *** outcome was gastrointestinal(gI)tolerance;additional parameters of interest were palatability and compliance(ratio of consumed *** volume).Data were evaluated *** All participants completed the studies and reported good *** symptoms were comparable before first and after last ingestion,55%and 65%(single and multiple dose regimens)did not report any gI *** consumed 96%and 94%of the prescribed volume,***,smell and appearance were rated as“good”or“excellent”on both days of recording(day 1 and day 7)by 75-90%of the participants in both *** A high energy,high protein ONS delivered in a small volume was well tolerated and accepted in older adults,with excellent compliance,independent of the delivery as single or multiple ***,this new ONS represents a clinically valuable option for high compliance to nutritional therapy.

关键词： Compliance Elderly Palatability Tolerance

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