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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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novel approach for evaluation of service reliability for electricity customers

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Science China(Technological Sciences) 2009年第9期52卷 2585-2590页

作者： JIAnG john n School of Electrical and Computer Engineering University of OklahomaNorman OK 73019 USA

Understanding reliability value for electricity customer is important to market-based reliability management. This paper proposes a novel approach to evaluate the reliability for electricity customers by using indifference curve between economic compensation for power interruption and service reliability of electricity. Indifference curve is formed by calculating different planning schemes of network expansion for different reliability requirements of customers, which reveals the information about economic values for different reliability levels for electricity customers, so that the reliability based on market supply demand mechanism can be established and economic signals can be provided for reliability management and enhancement.

关键词： power systems electricity market reliability customers’ outage cost indifference curve

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Surface plasma treatment effects on the molecular structure at polyimide/air and buried polyimide/epoxy interfaces

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Chinese Chemical Letters 2015年第4期26卷 449-454页

作者： john n.Myers Zhan Chen Department of Chemistry University of Michigan

Polyimides are widely used as chip passivation layers and organic substrates in microelectronic packaging. Plasma treatment has been used to enhance the interfacial properties of polyimides, but its molecular mechanism is not clear. In this research, the effects of polyimide surface plasma treatment on the molecular structures at corresponding polyimide/air and buried polyimideJepoxy interfaces were investigated in situ using sum frequency generation （SFG） vibrational spectroscopy. SFG results show that the polyimide backbone molecular structure was different at polyimide/air and polyimideJepoxy interfaces before and after plasma treatment. The different molecular structures at each interface indicate that structural reordering of the polyimide backbone occurred as a result of plasma treatment and contact with the epoxy adhesive. Furthermore, quantitative orientation analysis indicated that plasma treatment of polyimide surfaces altered the twist angle of the polyimide backbone at corresponding buried polyimide/epoxy interfaces. These SFG results indicate that plasma treatment of polymer surfaces can alter the molecular structure at corresponding polymer/air and buried polymer interfaces.

关键词： Molecular structureVibrational spectroscopySum frequency generation spectroscopy

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Gastroesophageal reflux disease and severe obesity:Fundoplication or bariatric surgery?

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World Journal of Gastroenterology 2010年第30期16卷 3757-3761页

作者： Vivek n Prachand john C Alverdy Center for the Surgical Treatment of Obesity Department of SurgeryUniversity of Chicago Pritzker School of MedicineChicagoIL 60637United States

Increases in the prevalence of obesity and gastroesophageal reflux disease (GERD) have paralleled one another over the past decade, which suggests the possibility of a linkage between these two processes. In both instances, surgical therapy is recognized as the most effective treatment for severe, refractory disease. Current surgical therapies for severe obesity include (in descending frequency) Roux-en-Y gastric bypass, adjustable gastric banding, sleeve gastrectomy, and biliopancreatic diversion with duodenal switch, while fundoplication remains the mainstay for the treatment of severe GERD. In several large series, however, the outcomes and durability of fundoplication in the setting of severe obesity are not as good as those in patients who are not severely obese. As such, bariatric surgery has been suggested as a potential alternative treatment for these patients. This article reviews current concepts in the putative pathophysiological mechanisms by which obesity contributes to gastroesophageal reflux and their implications with regards to surgical therapy for GERD in the setting of severe obesity.

关键词： Morbid obesity Gastroesophageal reflux disease Fundoplication Bariatric surgery Gastric bypass Sleeve gastrectomy

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Does defensive posture increase mimetic fidelity of caterpillars with eyespots to their putative snake models？

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Current Zoology 2014年第1期60卷 76-89页

作者： Thomas john HOSSIE Thomas n. SHERRATT Ottawa-Carleton Institute of Biology Carleton University 1125 Colonel By Drive Ottawa ON K1S 5B6 Canada Department of Biology Carleton University 1125 Colonel By Drive Ottawa ON K1S 5B6 Canada

Organisms often evolve behaviours that increase or reinforce the protection from predators afforded by their morpho- logical defences. For example, mimetic animals may adopt postures or locomotory behaviours that emulate a characteristic fea- ture of their model to increase predator deception. Caterpillars with eyespots are thought to mimic snakes, and when threatened many of these caterpillars adopt a posture that appears to enhance this resemblance. Herein we evaluate the quantitative strength of evidence of behavioural mimicry in the caterpillars of 14 species by comparing how closely a series of putative snake-mimicking caterpillars resemble snakes while at rest and when threatened. Specifically, we quantified the head morphology and eye position of a range of snake species, as well as the shape of the apparent head （i.e. anterior body segments） and position of eyespots in caterpillars resting or in their defensive posture. This allowed us to objectively examine evidence for an increased resemblance to either snakes generally, or to Viperidae snakes specifically, upon adopting the defensive posture. Widening the anterior body segments during the defensive posture typically made caterpillars appear more viper-like as opposed to more snake-like in general. Enhanced resemblance to vipers upon mounting the defensive posture was apparent only from the dorsal view. Laterally, caterpillars more closely resembled snakes in the resting posture and shifting to the defensive posture instead reduced mimetic fidelity, Overall we found evidence for behavioural mimicry in all 14 species examined. We highlight that objectively quantifying mimetic fidelity can help identify key features involved in deception .

关键词： Behaviour Geometr!c morphometrics Protective colouration Mimicry Morphology Vipers

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一次飞跃

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科学新闻 2015年第6期 83-84页

作者： john n.(Jack) kittinger 姜天海保护国际基金会

1960年,我的祖父在聚合物制成的气球吊篮里升上了102800英尺的高空,在简单的祷告后,他跳了下来。他的降落时间有4分多钟,然后安全地落在了新墨西哥州的沙漠上,这证明了人们可以在空间之战中生存下来,并开拓了在这种环境下保护人类生命... 详细信息

1960年,我的祖父在聚合物制成的气球吊篮里升上了102800英尺的高空,在简单的祷告后,他跳了下来。他的降落时间有4分多钟,然后安全地落在了新墨西哥州的沙漠上,这证明了人们可以在空间之战中生存下来,并开拓了在这种环境下保护人类生命的技术。多年以后,一个记者问第一个进入太空的美国人Alan Shepard会不会跳下来。"打死我都不会(Hell no)。"他说。最近,我感觉自己也在进行巨大的飞跃。过去的十年我都在树立学术造诣,一个科学家要想获得教师聘任

关键词：学术界回答职业生涯

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Delineation of groundwater potential zones in Theni district,Tamil nadu,using remote sensing,GIS and MIF techniques

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Geoscience Frontiers 2012年第2期3卷 189-196页

作者： n.S.Magesh n.Chandrasekar john Prince Soundranayagam Centre for Geotechnology Manonmaniam Sundaranar University

Integration of remote sensing data and the geographical information system （GIS） for the exploration of groundwater resources has become a breakthrough in the field of groundwater research, which assists in assessing, monitoring, and conserving groundwater resources. In the present paper, various groundwater potential zones for the assessment of groundwater availability in Theni district have been delineated using remote sensing and GIS techniques. Survey of India toposheets and IRS-IC satel- lite imageries are used to prepare various thematic layers viz. lithology, slope, land-use, lineament, drainage, soil, and rainfall were transformed to raster data using feature to raster converter tool in ArcGIS. The raster maps of these factors are allocated a fixed score and weight computed from multi influencing factor （MIF） technique. Moreover, each weighted thematic layer is statistically computed to get the groundwater potential zones. The groundwater potential zones thus obtained were divided into four categories, viz., very poor, poor, good, and very good zones. The result depicts the groundwater potential zones in the study area and found to be helpful in better planning and management of ground- water resonrces.

关键词： Groundwater potential zones India Remote sensing Geographic information system MIF technique

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Pitting and stress corrosion cracking studies on AISI type 316n stainless steel weldments

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Defence Technology（防务技术） 2018年第3期14卷 226-237页

作者： Anita Toppo M.G.Pujar n.Sreevidya john Philip Corrosion Science and Technology Division Indira Gandhi Centre for Atomic Research Materials Development and Technology Division Indira Gandhi Centre for Atomic Research

Pitting and stress corrosion cracking(SCC) studies on the 316 n stainless steel(SS) weldments in aswelded(AW) and thermally aged(solution annealing(SA), 550C/4 h and 750C/1 h) conditions were carried out in acidic and acidic chloride media. Pitting corrosion and SCC resistance was the highest for SA weldment, which was attributed to homogenization of microstructural and microchemical heterogeneities during solution annealing. SA specimen showed the most stable passive film as compared to AW weldment because of higher amount of delta-ferrite in AW weld metal, which resulted in an increased heterogeneity and inferior SCC resistance in AW. Stability of passive film was found to be adversely affected due to heat treatments(at 550C/4 h and 750C/1 h) because of the precipitation of carbide and sigma phases.

关键词：压力腐蚀不锈钢 AISI 焊接金属 SCC 稳定性氯化物微结构

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The nonlinear optical properties of a magneto-exciton in a strained Ga_(0.2)In_(0.8)As/GaAs quantum dot

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Chinese Physics B 2013年第10期22卷 479-485页

作者： n.R.Senthil Kumar A.john Peter Chang Kyoo Yoo Department of Physics SBM College of Engineering and Technology Department of Physics Govt.Arts CollegeMelur-625 106MaduraiIndia Center for Environmental Studies/Green Energy Center Deptartment of Environmental Science and EngineeringCollege of EngineeringKyung Hee UniversitySeocheon-dong 1Giheung-guYongin-SiGyeonggi-Do446-701South Korea

The magnetic field-dependent heavy hole excitonic states in a strained ***/GaAs quantum dot are investi- gated by taking into account the anisotropy, non-parabolicity of the conduction band, and the geometrical confinement. The strained quantum dot is considered as a parabolic dot of InAs embedded in a GaAs barrier material. The dependence of the effective excitonic g-factor as a function of dot radius and the magnetic field strength is numerically measured. The interband optical transition energy as a function of geometrical confinement is computed in the presence of a mag- netic field. The magnetic field-dependent oscillator strength of interband transition under the geometrical confinement is studied. The exchange enhancements as a function of dot radius are observed for various magnetic field strengths in a strained ***/GaAs quantum dot. Heavy hole excitonic absorption spectra, the changes in refractive index, and the third-order susceptibility of third-order harmonic generation are investigated in the Gao.2Ino.8As/GaAs quantum dot. The result shows that the effect of magnetic field strength is more strongly dependent on the nonlinear optical property in a low-dimensional semiconductor system.

关键词： oscillator strength exciton quantum dot

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Structure-Preserving Finite-Element Schemes for the Euler-Poisson Equations

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Communications in Computational Physics 2023年第3期33卷 647-691页

作者： Matthias Maier john n.Shadid Ignacio Tomas Department of Mathematics Texas A&M University3368 TAMUCollege StationTX 77843USA Sandia national Laboratories P.O.Box 5800MS 1320AlbuquerqueNM 87185USA Department of Mathematics and Statistics University of New MexicoMSC011115AlbuquerqueNM 87131USA Department of Mathematics&Statistics Texas Tech University2500 BroadwayLubbockTX 79409USA.

We discuss structure-preserving numerical discretizations for repulsive and attractive Euler-Poisson equations that find applications in fluid-plasma and selfgravitation *** scheme is fully discrete and structure preserving in the sense that it maintains a discrete energy law,as well as hyperbolic invariant domain properties,such as positivity of the density and a minimum principle of the specific entropy.A detailed discussion of algorithmic details is given,as well as proofs of the claimed *** present computational experiments corroborating our analytical findings and demonstrating the computational capabilities of the scheme.

关键词： Euler-Poisson equations operator splitting invariant domain preservation discrete energy balance.

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