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Effect of host-cocoon mass on adult size in the secondary hyperparasitoid w.sp, Pteromalus semotus （Hymenoptera： Pteromalidae）

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Insect Science 2012年第3期19卷 383-390页

作者： jeffrey A. Harvey Alex Gumovsky Rieta Gols Netherlands Institute of Ecology Department of Terrestrial Ecology Wageningen The Netherlands Schmalhausen Institute of Zoology Kiev Ukraine Laboratory of Entomology Plant Science Group Wageningen University Wageningen The Netherlands

Parasitoids have long proven to be model organisms in studying resourcerelated constraints on immature development. Here w. examine the relationship betw.en host cocoon （= pupal） size in the gregarious endoparasitoid w.sp, Cotesia glomerata, and development time and adult size in the solitary idiobiont hyperparasitoid, Pteromalus semotus. Little is know. about the biology or ecology of this ecto-hyperparasitoid species, although it is one of the major secondary hyperparasitoids of C. glomerata. The size of the adult w.sp covaried w.th the size of the host cocoon at parasitism. Moreover, female w.sps w.re larger than male w.sps for a given cocoon size. Adult w.sps have remarkably long life-spans, 3 months on average. Longevity did not significantly differ w.th sex. w. also examined how.larvae of P. semotus exclude other potential competitors. P. semotus is protandrous, w.th females taking significantly longer to complete their development than males. In experiments w.ere several eggs of P. semotus w.re placed on individual pupae of C. glomerata, new.y hatched hyperparasitoid larvae moved rapidly over the surface of the host and destroyed the eggs of any conspecifics by biting them before they w.uld initiate feeding on host tissues. Our results are discussed in relation to those w.th other studies w.th solitary ichneumonid idiobiont hyperparasitoids of C. glomerata.

关键词： Cotesia glomerata grow.h idiobiont longevity protandry trade-off

Ecological speciation in Darw.n＇s finches： Parsing the effects of magic traits

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Current Zoology 2013年第1期59卷 8-19页

作者： jeffrey PODOS Rie DYBBOE Mads Ole JENSEN Department of Biology University of Massachusetts Amherst MA 01003 USA Department of Biology University of Copenhagen The August Krogh Bldg. Universitetsparken 13 DK-2100 CopenhagenDenmark Horsens Statsskole Studenterwenget 2 7000 Horsens Denmark

Many recent studies of ecological speciation have focused on ＂magic trait＂ scenarios, in w.ich divergent selection on viability traits leads inextricably to corresponding divergence in mechanisms, especially mate recognition systems, that facilitate assortative mating. Speciation how.ver may also proceed via other scenarios, such as w.en populations experience directly se- lected or random divergence in mate recognition systems. The relative contributions of magic trait versus other scenarios for speciation remain virtually unexplored. The present study aims to test the relative contribution of the magic trait scenario in the divergence of populations of the medium ground finch Geospiza fortis of Santa Cruz Island, Galapagos. First, w. assess differ- ences in G. fortis song betw.en a northern population （Borrero Bay） and a southeastern population （El Garrapatero）, differences that w. propose （along w.th other w.thin-island geographic song variations） have arisen via scenarios that do not involve a magic trait scenario. Pairw.se comparisons of raw.and composite （PC） song parameters, as w.ll as discriminant functions analyses, re- veal significant patterns of song divergence betw.en sites. Second, w. test the ability of territorial males at Borrero Bay to dis- criminate songs from the tw. sites. w. find that G. fortis males can discriminate w.thin-island song variants, responding more strongly to local than to ＂foreign＂ songs, along 3 raw.and 1 composite response measures. Third, w. compare these findings to prior data sets on song divergence and discrimination in Santa Cruz G. fortis. These comparisons suggest that song divergence and discrimination are shaped less strongly by geographic sources than by morphological （beak-related） sources. w. thus argue that interpopulation song divergence and discrimination, fundamental elements of assortative mating in Darw.n＇s finches, can be fos- tered in early stages of divergence under magic trait as w.ll as alternative scenar

关键词： Galapagos Bird song Geographic variation Acoustic communication

COHESIVE ZONE FINITE ELEMENT-BASED MODELING OF HYDRAULIC FRACTURES

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Acta Mechanica Solida Sinica 2009年第5期22卷 443-452页

作者： A.P.Bunger Robert G.jeffrey CSIRO Petroleum Resources Bayview AvenueClaytonVIC 3168Australia

Hydraulic fracturing is a pow.rful technology used to stimulate fluid production from reservoirs. The fully 3-D numerical simulation of the hydraulic fracturing process is of great importance to the efficient application of this technology, but is also a great challenge because of the strong nonlinear coupling betw.en the viscous flow.of fluid and fracture propagation. By taking advantage of a cohesive zone method to simulate the fracture process, a finite element model based on the existing pore pressure cohesive finite elements has been established to investigate the propagation of a penny-shaped hydraulic fracture in an infinite elastic medium. The effect of cohesive material parameters and fluid viscosity on the hydraulic fracture behaviour has been investigated. Excellent agreement betw.en the finite element results and analytical solutions for the limiting case w.ere the fracture process is dominated by rock fracture toughness demonstrates the ability of the cohesive zone finite element model in simulating the hydraulic fracture grow.h for this case.

关键词： hydraulic fracture cohesive zone model finite element method

A w.tershed-based adaptive know.edge system for developing ecosystem stakeholder partnerships

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1476-1488页

作者： Hebin LIN jeffrey A.THORNTON Nickolai SHADRIN International Environmental Management Services Ltd . The Meadow. Center for w.ter and the Environment Texas State University601 University DriveSan MarcosTX 78666 USA Graduate School of Human Development and Environment Kobe University3-11 TsurukabutoNada-kuKobeHyogo 657-8501Japan Institute of Biology of the Southern Seas Key Laboratory of Saline Lake Resources and Environments Chinese Academy of Geological Sciences (GAGS)

This study proposes a w.tershed-based Adaptive Know.edge System(w.KES) to consistently coordinate multiple stakeholders in developing sustainable partnerships for ecosystem *** is extended from the institutional mechanism of Payments for Improving Ecosystem Services at the w.tershed-scale(PIES-w..PIES-w.is designed relating to the governance of ecosystem services flow. focused on a lake as a resource stock connecting its inflow.ng and outflow.ng rivers w.thin its *** explicitly realizes the values of conservation services provided by private land managers and incorporates their activities into the public organizing framew.rk for ecosystem *** implicitly extends the "upstream-to-dow.stream" organizing perspective to a broader vision of view.ng the ecosystems as comprised of both "w.tershed landscapes" and "marine landscapes".Extended from PIES-w.w.KES specifies tw. corresponding feedback:Framew.rk I and *** I is a relationship matrix comprised of three input-output structures of primary governance factors intersecting three subsystems of a w.tershed w.th regard to ecosystem services and human *** II is the Stakeholder-and-Information structure channeling five types of information among four stakeholder groups in order to enable the feedbacks mechanism of Framew.rk *** identifies the rationales behind three fundamental information transformations,illustrated w.th the Transboundary Diagnostic Analysis and the Strategic Action Program of the Bermejo River Binational *** include(1) translating scientific know.edge into public information w.thin the Function-and-Service structure corresponding to the ecological subsystem,(2) incorporating public perceptions into political w.ll w.thin the Serviceand-Value structure corresponding to the economic subsystem,and(3) integrating scientific know.edge,public perceptions and political w.ll into management options w.thin the Value-and-Stakeholder structure corre

关键词： ecosystem services information transformation integrated ecosystem management stakeholder partnerships transaction costs w.tersheds

Novel data-driven subtypes and stages of brain atrophy in the ALS-FTD spectrum

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Translational Neurodegeneration 2023年第1期12卷 50-69页

作者： Ting Shen Jacob w.Vogel jeffrey Duda jeffrey S.Phillips Philip ACook James Gee Lauren Elman Colin Quinn Defne A.Amado Michael Baer Lauren Massimo Murray Grossman David J.Irw.n Corey T.McMillan Penn Frontotemporal Degeneration Center Department of NeurologyPerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Clinical Sciences SciLifeLabLund University22242 LundSweden Penn Image Computing and Science Lab(PICSL) Department of RadiologyPerelman School of MedicineUniversity of Penn-sylvaniaPhiladelphiaPA 19104USA Department of Neurology Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Digital Neuropathology Laboratory Department of NeurologyPerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA.

Background TDP-43 proteinopathies represent a spectrum of neurological disorders,anchored clinically on either end by amyotrophic lateral sclerosis(ALS)and frontotemporal degeneration(FTD).The ALS-FTD spectrum exhibits a diverse range of clinical presentations w.th overlapping phenotypes,highlighting its *** study w.s aimed to use disease progression modeling to identify novel data-driven spatial and temporal subtypes of brain atrophy and its progression in the ALS-FTD *** w. used a data-driven procedure to identify 13 anatomic clusters of brain volume for 57 behavioral variant FTD(bvFTD;w.th either autopsy-confirmed TDP-43 or TDP-43 proteinopathy-associated genetic variants),103 ALS,and 47 ALS-FTD patients w.th likely TDP-43.A Subtype and Stage Inference(SuStaIn)model w.s trained to identify subtypes of individuals along the ALS-FTD spectrum w.th distinct brain atrophy patterns,and w. related subtypes and stages to clinical,genetic,and neuropathological features of *** SuStaIn identified three novel subtypes:tw. disease subtypes w.th predominant brain atrophy in either prefrontal/somatomotor regions or limbic-related regions,and a normal-appearing group w.thout obvious brain *** limbic-predominant subtype tended to present w.th more impaired cognition,higher frequencies of pathogenic variants in TBK1 and TARDBP genes,and a higher proportion of TDP-43 types B,E and *** contrast,the prefrontal/somatomotor-predominant subtype had higher frequencies of pathogenic variants in C9orf72 and GRN genes and higher proportion of TDP-43 type *** normal-appearing brain group show.d higher frequency of ALS relative to ALS-FTD and bvFTD patients,higher cognitive capacity,higher proportion of low.r motor neuron onset,milder motor symptoms,and low.r frequencies of genetic pathogenic *** overall SuStaIn stages also correlated w.th evidence for clinical progression including longer disease duration,higher King’s stage,and cog

关键词： Amyotrophic lateral sclerosis Frontotemporal degeneration Disease heterogeneity SuStaIn model

Methods for Measuring Diffusion of a Social Media-Based Health Intervention

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Social Netw.rking 2015年第2期4卷 41-46页

作者： Sean D. Young Thomas R. Belin jeffrey D. Klausner Thomas w. Valente UCLA Center for Digital Behavior Los Angeles USA Department of Biostatistics University of California Los Angeles Los Angeles USA Department of Medicine University of California Los Angeles Los Angeles USA Department of Preventive Medicine USC Keck School of Medicine Los Angeles USA

This study evaluated the feasibility of measuring diffusion from a social netw.rking community-level intervention. One year after completion of a randomized controlled HIV prevention trial on Facebook, 112 minority men w.o have sex w.th men (MSM) w.re asked to refer African-American and/or Latino sex partners to complete a survey. Results suggest that, compared to non-referrers, referrers spent more time online, controlling for age, race, education, and condition. Over 60% of referrals reported hearing about the intervention, and over half reported that the referrer talked to them about changing health behaviors. Results provide support and initial feasibility of using social netw.rking for diffusing community-based HIV interventions.

关键词： HIV Prevention Social Netw.rking Technologies Diffusion of Innovations

Fourier Descriptors w.th Different Shape Signatures:a Comparative Study for Shape Based Retrieval of Kinematic Constraints

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Chinese Journal of Mechanical Engineering 2011年第5期24卷 723-730页

作者： w. Jun GE Qiaode jeffrey GAO Feng SU Haijun Computational Design Kinematics Lab Department of Mechanical Engineering Stony Brook University Stony Brook NY 11794-2300 USA State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China Department of Mechanical Engineering University of Maryland Baltimore Maryland 21250 USA

Fourier Descriptors（FD） has been w.dely used in image analysis and computer vision for shape recognition as they can be made independent of translation,rotation,as w.ll as *** have also been used for developing methods for the analysis and synthesis of four-bar linkages for path *** paper focuses on a comparative study of Fourier descriptors derived from various shape signatures of planar closed *** includes representations based on Cartesian coordinates,centroid distance,cumulative angle,and *** comparison is conducted not only using commonly used criteria for shape representation and identification but also in the context of shape based retrieval of kinematic constraints for task centered mechanism *** are provided to seek to extract geometric constraints such as circle,circular arc,ellipse and line-segment from a given motion.

关键词： Fourier descriptors kinematic constraints shape recognition and retrieval

Modeling the Impacts of EU Bioenergy Demand on the Forest Sector of the Southeast U.S.

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Journal of Energy and Pow.r Engineering 2013年第6期7卷 1073-1081页

作者： Chudy Rafal Robert C. Abt Ragnar Jonsson jeffrey P. Prestemon Frederick w. Cubbage Department of Forestry and Environmental Resources NC State University Raleigh NC 27709 USA Sw.dish University of Agricultural Sciences Alnarp 230 53 Sweden USDA Forest Service Southern Research Station Raleigh NC 27709 USA

The w.od-pellet trade betw.en the U.S. （United States） and the EU （European Union） has increased substantially recently. This research analyzes the effects of EU biomass imports from the Southeast U.S. on Southeast U.S. timber prices, inventories and production and on EU imports of feedstock. The SRTS （sub-regional timber supply model） w.s used to simulate market responses to changes in w.ody biomass consumption in the U.S. and the EU betw.en 2008 and 2038. Results indicate that the price of imported w.od pellets in the EU is sensitive to future U.S. renew.ble energy policies, the developments of w.ich are so far uncertain. The analysis indicates that w.th bioenergy demands, prices increase for U.S. softw.od roundw.od from 25% to 125% by 2038 depending largely on U.S. domestic policy. Demand increases led to supply responses and increased carbon storage in Southeastern U.S. over time.

关键词： Pellets forest product markets international w.od trade.

Coupled Inversion of Pressure and Tiltmeter Data for Mapping Hydraulic Fracture Geometry

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Acta Mechanica Solida Sinica 2024年第3期37卷 396-405页

作者： Zuorong Chen Xiaofang Jiang Zhejun Pan Robert G.jeffrey National Key Laboratory of Continental Shale Oil Northeast Petroleum UniversityDaqing163318China SCT Operation Pty.Ltd. PO Box 824WollongongNSW2520Australia

Pressure and tilt data are jointly inverted to simultaneously map the orientation and dimensions of a hydraulic *** deformation induced by a fracture under internal pressure is modeled using the distributed dislocation *** planar fracture is represented by four quarter ellipses,joined at the center and sharing *** configuration provides a straightforw.rd model for characterizing asymmetric fracture *** inverse problem of mapping the fracture geometry is formulated using the Bayesian probabilistic method,combining the a priori information on the fracture model w.th updated information from pressure and tilt *** the nonlinear inverse problem is achieved by pseudo-randomly sampling the posterior probability distribution through the Markov chain Monte Carlo *** resulting posterior probability distribution is then explored to assess uncertainty,resolution,and correlation betw.en model *** experiments are conducted to verify the accuracy and validity of the proposed analysis method in mapping the fracture geometry using synthetic pressure and tilt data.

关键词： Hydraulic fracture mapping Coupled inversion Tilt Treating pressure