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Climate change effects on rangelands and rangeland management:affirming the need for monitoring

ecosystem Health and Sustainability 2017年第3期3卷 1-14页

作者： Daniel W.McCollum john A.Tanaka Jack A.Morgan john e.mitchell William e.Fox Kristie A.Maczko Lori Hidinger Clifford S.Duke Urs P.Kreuter Rocky Mountain Research Station USDAForest Service240 W.Prospect RoadFort CollinsColorado 80526 USA James C.Hageman Sustainable Agriculture Research and extension Center University of WyomingDept 33541000 E.University AvenueLaramieWyoming 82071 USA USDA ARS Rangelands Resources Research Unit8408 Hildreth RoadCheyenneWyoming 82009 USA Texas A&M AgriLife Research Ecosystem Science&Management720 E.Blackland RoadTempleTexas 76502 USA Consortium for Science Policyand OutcomesArizona State UniversityPO Box 875603TempeArizona 85287 USA ecological Society of America 1990 M StreetNWSuite 700WashingtonD.C.20036 USA ecosystem Science and Management Texas A&M University2138 TAMUCollege StationTexas 77843 USA

Uncertainty as to the extent and magnitude of changes in conditions that might occur due to climate change poses a problem for land and resource managers as they seek to adapt to changes and mitigate effects of climate *** illustrate using scenarios of projected future conditions on rangelands in the Northern Great Plains and Desert Southwest of the United *** two regions are different in the ways climate change is projected to affect the *** of a longer and warmer growing season in the Northern Great Plains could lead to increased forage production and land *** uncertain effects on summer monsoons that primarily control rangeland productivity in the Desert Southwest,combined with the possibility of more intense and/or frequent drought events,could present land managers with challenges stemming from decreased forage production and land *** projections,though uncertain,provide land managers with basic insight into future conditions they might *** need more.A focus on vulnerability and resilience,with explicit recognition of interactions between ecological and socio-economic factors,coupled with systematic monitoring and assessment of observable conditions on the land to supplement information based on climate projections,will more effectively provide critical and specific information managers need to adaptively manage rangelands under uncertain climate futures.

关键词： adaptive management climate change indicators monitoring rangelands resilience uncertainty vulnerability

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explicit and Parameterized episodes of Warm-Season Precipitation over the Continental United States

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Advances in Atmospheric Sciences 2006年第1期23卷 91-105页

作者： mitchell W. MONCRIeFF john D. TUTTLe Richard e. CARBONe National Center for Atmospheric Research BoulderColorado 80307-3000U. S. A.

This paper describes explicit and parameterized simulations of midsummer precipitation over the continental United States for two distinct episodes： moderate large-scale forcing and weak forcing. The objective is to demonstrate the capability of explicit convection at currently affordable grid-resolution and compare it with parameterized realizations. Under moderate forcing, 3-kin grid-resolution explicit simulations represent rainfall coherence remarkably well. The observed daily convective generation near the Continental Divide and the subsequent organization and propagation are reproduced qualitatively. The propagation speed, zonal extent and duration of the rainfall streaks compare favorably with their observed counterparts, although the streak frequency is underestimated. The simulations at -10-km grid-resolution applying conventional convective parameterization schemes also replicate reasonably well the diurnal convective regeneration in moderate forcing. The performance of the 3-km grid-resolution model demonstrates the potential of -1-km-resolution explicit cloud-resolving models for the prediction of warm season precipitation for moderately forced environments. In weak forcing conditions, however, predictions of precipitation coherence and diurnal variability are much poorer. This suggests that an even finer resolution explicit model is required to adequately treat convective initiation and upscale organization typical of the warm season over the continental U.S.

关键词： warm-season precipitation explicit simulation convective parameterization

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Search for a natural scientific measure of economy

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Frontiers of environmental Science & engineering 2011年第1期5卷 111-118页

作者： john e COULTeR Xiwangzhuang Shuangqing RdHaidianBeijing 100084China

Through human history,wealth has been measured in grain,gold,and,now,*** counterfeiting of coins and notes goes back a long way,it is only with electronic financial accounting in a global economy tainted by toxic loans and imaginary funds that there is an urgency to search for a realistic objective way to monitor and regulate what we are doing to our earth and *** schemes using analysis of utility functions,oil equivalents,entropy,energy,and other units have been tried and,while helping to understand some basic processes and flows,have always been swamped by the machinations of financiers and the attention big sums of money ***,the concept of exergy,pioneered in eastern europe in the 1950s,is being researched,developed,and applied,especially in China,driven by the desperation to measure the reality beyond the twin specters of global financial and environmental crises.A rough inventory of the matter in the biosphere at the coordinate details of an angstrom and an appreciation of how humans harness and manipulate electromagnetic forces can be enlightening as to what is and is not *** that understanding,any financial estimate and proposed stimulus packages or IMF reform will be wildly wrong and may even be headed in the wrong direction.

关键词： climate change financial crisis energy exergy environment

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Development of Light Weight Structures to Provide Blast-Resistant Designs

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Transactions of Tianjin University 2006年第B09期12卷 16-21页

作者： CRAWFORD john e Karagozian & Case 2550 N.Hollywood Way #500BurbankCA 91505USA

In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. However, structures composed of COLD-FORMeD steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PHF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PHF are described.

关键词： blast containment package handling facility hardened design light weight structures COLD-FORMeD steel structures

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Simulation of Fragment Impact on Multi-Layer Targets Using Contact Method

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Transactions of Tianjin University 2006年第B09期12卷 152-157页

作者： CRAWFORD john e Karagozian & Case 2550 N.Hollywood WaySuite 500BurbankCA 91505USA

Cased explosives generate highly energetic fragments as their casing breaks up. Due to the complexity of casing fragment related behavior such as embedment, perforation and ricochet, it may be insufficient to use equivalent triangular pressure loading in fragment impact simulations. This simplified method may over- or under-predict the target response. Recently, a procedure using contact techniques has been proposed to overcome such difficulties. It has been shown that the new method has the inherent capability in modeling the multi-piece and multi-hit fragment impact problems in a more realistic way. To investigate the applicability of the proposed method to simulations involving multi-layer penetration, the selected problems of fragment impact on multi-layer targets are described in this paper. It is demonstrated that this method is capable of predicting the complicated multi-layer structural response caused by fragment impact and penetration. Modeling procedures and some technical issues are also discussed.

关键词： contact finite element fragment impact multi-layer penetration simulation

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SWITCHING AND SeQUeNCING AVAILABLe THeRAPIeS SO AS TO MAXIMIZe A PATIeNT＇S eXPeCTeD TOTAL LIFeTIMe

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International Journal of Biomathematics 2012年第4期5卷 113-125页

作者： john e. GOULIONIS Department of Statistics and Insurance Science University of Piraeus 80 Karaoli a Dimitriou Street 18534 Piraeus Greece

This paper has focused on applying mathematical techniques to address fundamental question in therapy planning when to switch, and how to sequence therapies. We consider switching and sequencing available therapies so as to maximize a patient＇s expected total lifetime. We assume knowledge only about the lifetime distributions induced by the therapies. We discuss a specialization of this model that is tailored to a frequently reoccurring type of management problem, where our goal is to determine the best timing for testing and treatment decisions for patients with ischemic heart disease. Typically, decisions are made with an overall, goal of maximizing the patient＇s expected lifetime or quality-adjusted lifetime.

关键词： expected total lifetime maintenance ischemic heart disease stochasticordering relationships statistical distributions.

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A FAST LAGRANGIAN SIMULATION MeTHOD FOR FLOW ANALYSIS AND RUNNeR DeSIGN IN PeLTON TURBINeS

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Journal of Hydrodynamics 2012年第6期24卷 930-941页

作者： ANAGNOSTOPOULOS john S. PAPANTONIS Dimitris e. School of Mechanical engineering National Technical University of Athens

In the present work, an alternative numerical methodology is developed for a fast and effective simulation and analysis of the complex flow and energy conversion in Pelton impulse hydro turbines. The algorithm is based on the Lagrangian approach and the unsteady free-surface flow during the jet-bucket interaction is simulated by tracking the trajectories of representative fluid particles at very low computer cost. Modern regression tools are implemented in a new parameterization technique of the inner bucket surface. Key-feature of the model is the introduction of additional terms into the particle motion equations to account for various hydraulic losses and the flow spreading, which are regulated and evaluated with the aid of experimental data in a Laboratory Pelton turbine. The model is applied to study the jet-runner interaction in various operation conditions and then to perform numerical design optimization of the bucket shape, using a stochastic optimizer based on evolutionary algorithms. The obtained optimum runner attains remarkably higher hydraulic efficiency in the entire load range. Finally, a new small Pelton turbine （150 kW） is designed, manufactured and tested in the Laboratory, and its performance and efficiency verify the model predictions.

关键词： Pelton turbine hydraulic efficiency Lagrangian simulation bucket shape parameterization numerical design optimization

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25 Years of sensory drive： the evidence and its watery bias

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Current Zoology 2018年第4期64卷 471-484页

作者： Molly e. CUMMINGS john A. eNDLeR Department of Integrative Biology University of Texas Austin TX 78712 USA School of Life and environmental Sciences Deakin University Waurn Ponds VIC 3216 Australia

It has been 25years since the formalization of the Sensory Drive hypothesis was published in the American Naturalist （1992）. Since then, there has been an explosion of research identifying its utility in contributing to our understanding of inter- and intra-specific variation in sensory systems and signaling properties. The main tenet of Sensory Drive is that environmental characteristics will influence the evolutionary trajectory of both sensory （detecting capabilities） and signaling （detectable features and behaviors） traits in predictable directions. We review the accumulating evidence in 154 studies addressing these questions and categorized their approach in terms of testing for environmental influence on sensory tuning, signal characteristics, or both. For the subset of studies that examined sensory tuning, there was greater support for Sensory Drive processes shaping visual than auditory tuning, and it was more prevalent in aquatic than terrestrial habitats. Terrestrial habitats and visual traits were the prevalent habitat and sensory modality in the 104 studies showing support for environmental influence on signaling properties. An additional 19 studies that found no supporting evidence for environmental influence on signaling traits were all based in terrestrial ecosystems and almost exclusively involved auditory signals. Only 29 studies examined the complete coevolutionary process between sensory and signaling traits and were dominated by fish visual communication. We discuss biophysical factors that may contribute to the visual and aquatic bias for Sensory Drive evidence, as well as biotic factors that may contribute to the lack of Sensory Drive processes in terrestrial acoustic signaling systems.

关键词： animal communication sensory drive sensory ecology sexual selection

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Is Takotsubo syndrome in patients receiving chemotherapy drug-specific?

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World Journal of Clinical Cases 2015年第2期3卷 204-205页

作者： john e Madias Icahn School of Medicine at Mount Sinai Division of Cardiology Elmhurst Hospital Center

In commenting on a case report of a 55-year-old man who suffered Takotsubo syndrome(TTS), in the setting of receiving chemotherapy with cytarabine and daunorubicin for acute myeloid leukemia, the author expresses his views that TTS in the setting of chemotherapy for malignancies may not be chemotherapeutic drug-specific(like in the chemotherapeutic drug induced-cardiomyopathy), but may be due to the emotional and physical stresses resulting from the realization of having diagnosed with a malignancy, and the diagnostic testing, and therapeutic management which follows.

关键词： Daunorubicin Radiotherapy Cardiotoxicity Takotsubo syndrome Malignancies Chemotherapy Cytarabine Anthracyclines Cardiomyopathy Autonomic sympathetic Nervous system

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A Study of the Velocity Field during evaporation of Sessile Water and Water/ethanol Drops

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Journal of Bionic engineering 2010年第4期7卷 321-328页

作者： john R.e.Christy Khellil Sefiane euan Munro School of engineering University of Edinburgh

Many studies have investigated evaporation of sessile drops in an attempt to understand the effect of wetting on theevaporation *** interest has also increased in the deposition of particles from such drops,with evaporative massflux being deemed to be responsible for ring-like deposits,and counteraction of the mass flux by Marangoni convection explainingmore uniform deposition *** of such deposition processes is important in biological applications,such as the Litos test-system endorsed by the Russian Ministry of Health for diagnosis of urolithiasis and the evaporation ofcolloidal drops for depositing and organizing proteins and *** most cases where deposition from evaporating drops hasbeen studied,velocity information is inferred from the final deposition pattern or from mathematical modeling based on simplifiedmodels of the physics of the evaporation *** this study we have directly measured the flow velocities in the baseof sessile drops,using micro particle image velocimetry,viewing the drop from below,through the cover *** water drops,a radial pattern of flow was observed with a maximum velocity close to but not at the pinned outer *** ‘azeotropic’ethanol/water mixtures,the velocity field is more chaotic to begin with,passing through a phase involving three or four recirculationcells and finally having the same radial pattern as for water drops.

关键词： evaporation sessile drop velocimetry particle deposition μPIV

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