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Variations in Growth, Photosynthesis and defense System Among Four weed Species Under Increased UV-B Radiation

Journal of Integrative Plant Biology 2007年第5期49卷 621-627页

作者： Shiwen wang Liusheng duan anthony Egrinya Eneji Zhaohu Li State Key Laboratory of Plant Physiology and Biochemistry Centre of Crop Chemical Control Department of Agronomy China Agricultural University Beijing 100094 China

weed tolerance of UV-B radiation varies with species, and the radiation could affect weed ecology and management. Variations In growth, photosynthesis and defense system among four important agronomic weeds, Abutllon theophrastl Medlk, Amaranthus retroflexus L., digitaria sanguinalis （L.） Scop and Chloris virgata Swartz, under Increased UV-B radiation （ambient and increased radiation at 2.7, 5.4 and 10.8 kJ.m^-2.d-1） were studied In the greenhouse experiment. After 2 weeks of radiation, the shoots＇ dry mass decreased with increasing UV-B radiation except for d. sanguinalis. The reduction in biomass was the result of changes in morphology and physiology. Higher levels of UV-B treatment decreased the leaf area, plant height, net photosynthetic rate and chlorophyll contents, while it increased the contents of wax and UV-B absorbing compound in all species, except for A. retroflexus, which did not increase significantly. The activity of superoxide dismutase, catalase, ascorbate peroxide and the content of ascorblc acid changed differently among the weed species as UV-B radiation increased. d. sangulnalls was the most tolerant and A. retroflexus the most sensitive to increased UV-B radiation. The results also show that the two grass species （d. sanguinalis and C. virgata） were more tolerant to UV-B radiation than the two broadleafed species （A. theophrasti and A. retroflexus）. The UV-B absorbing compound and leaf wax played Important roles against UV-B damages in the two grass weeds. The overall results suggest that weed community, competition and management will be altered by continuous ozone depletion.

关键词： crabgrass fingergrass leaf wax redroot UV-B absorbing compounds UV-B radiation velvetleaf

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A nano-engineered graphene/carbon nitride hybrid for photocatalytic hydrogen evolution

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Journal of Energy Chemistry 2016年第2期25卷 223-225页

作者： Xiaobo Li Yao Zheng anthony F.Masters Thomas Maschmeyer Laboratory of Advanced Catalysis for Sustainability School of ChemistryThe University of Sydney School of Chemical Engineering University of AdelaideAdelaide Australian Institute of Nanoscale Science and Technology The University of Sydney

A metal-free photocatalytic hydrogen evolution system was successfully fabricated using heteroatom doped graphene materials as electron-transfer co-catalysts and carbon nitride as a semiconductor. The catalytic role of graphene is significantly dependent on the heteroatom dopant of the graphene, such as O, S, B, N doped/undoped graphene co-catalysts, and N-graphene shows the best catalytic hydrogen evolution rate.

关键词： Carbon nitride Co-catalyst Graphene Hydrogen evolution Photocatalysis

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Analysis of a 1 kw organic Rankine cycle using a scroll expander for engine coolant and exhaust heat recovery

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Frontiers in Energy 2017年第4期11卷 527-534页

作者： Yiji LU anthony Paul ROSKILLY Long JIANG Longfei CHEN Xiaoli YU Sir Joseph Swan Centre for Energy Research Newcastle University Newcastle NE1 7RU UK Institute of Refrigeration and Cryogenics Shanghai Jiao TongUniversity Shanghai 200240 China School of Energy and Power Engineering Beihang University Beijing 100191 China department of Energy Engineering Zhejiang University Hangzhou310027 China

The development of engine waste heat recov- ery technologies attracts ever increasing interests due to the rising strict policy requirements and environmental con- cerns. This paper presented the study of engine coolant and exhaust heat recovery using organic Rankine cycle （ORC）. Eight working fluids were selected to evaluate and compare the performance of the integrated waste heat recovery system. Rather than the conventional engine ORC system mainly focusing on the utilization of exhaust energy, this work proposed to fully use the engine coolant energy by changing the designed parameters of the ORC system. The case study selected a small engine as the heat source to drive the ORC system using a scroll expander for power production. The evaluation results suggest that under the engine rated condition, the solution to fully recover the engine coolant energy can achieve a higher power generation performance than that of the conven- tional engine ORC system. The results suggest that adding a recuperator to the ORC system can potentially improve the system performance when the working fluids are dry and the overall dumped heat demand of the system can be reduced by 12% under optimal conditions. when the ORC evaporating and condensing temperature are respectivelyset at 85℃ and 30℃, the integrated engine waste heat recovery system can improve the overall system efficiency by 9.3% with R600, R600a or n-Pentane as the working fluid.

关键词： organic Rankine cycle scroll expander cool-ant and exhaust recovery internal combustion engine

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Variability among autumn migration patterns of Mongolian Common Shelducks(Tadorna tadorna)

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Avian Research 2019年第1期10卷 71-81页

作者： Xin wang Lei Cao Nyambayar Batbayar anthony david Fox State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences wildlife Science and Conservation Center department of Bioscience Aarhus University

Background:Avian migrants moving between common breeding and wintering areas may adopt different migration routes,and consequently affect ***,this pattern has rarely been investigated,especially in ***,autumn migration patterns of the Common Shelduck(Tadorna tadorna) have never been ***:we used GPS transmitters to track,for the first time,the autumn migration of the Common Shelduck in East Asia(n = 14).Results:The Common Shelduck undertook a broadly northwest–southeast autumn migration,taking a mean of 91.7 ± 38.7(Sd) days to cover a mean distance of 1712.9 ± 450.5 km at a speed of 89.4 ± 226.5 km/*** birds used 2.5 ± 1.8 stopover sites,and the total stopover duration was 81.9 ± 38.7 *** were considerable betweenindividual variations in the onset(24 August to 28 September) and completion(29 September to 11 January) of migration,distance(1070.2–2396.4 km),speed(14.7-734.0 km/day),the index of straightness(0.6-1.0),duration(1.5-151.8 days),stopover times(0-5) and total stopover durations(0-148.1).More direct migration routes were associated with fewer and shorter stopovers(p = 0.003 in both cases).Post-breeding and wintering site habitat use was similar between individuals,whereas stopover site habitat use varied considerably within and between ***:Our study show.d remarkable variability in Shelduck migration patterns,which was likely associated with refuelling patterns en *** understand fully the migration diversity and flexibility of habitat-use,we need to track more birds to increase representativeness,using accelerometer-integrated transmitters to investigate behaviours in different habitats.

关键词： Autumn migration East Asian-Australasian flyway Habitat use

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Insect immune resistance to parasitoids

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Insect Science 2008年第1期15卷 67-87页

作者： Yves Carton Marylène Poirié anthony J. Nappi Laboratoire Evolution Génomes et Spéciation CNRS 91198 Gif/Yvette France and Université Paris-Sud 11 91405 Orsay CedexFrance Unité Mixte de Recherches 1112 'Réponse des Organismes aux Stress Environnementaux' Université Nice-Sophia AntipolisInstitut National de la Recherche Agronomique 400 route des Chappes 06903 Sophia-Antipofis France department of Biology Loyola University of Chicago Chicago Illinois 60525 USA

Insect host-parasitoid interactions involve complex physiological, biochemical and genetic interactions. Against endoparasitoids, immune-competent hosts initiate a blood cell-mediated response that quickly destroys the intruders and envelops them in a multilayered melanotic capsule. during the past decade, considerable progress has been made in identifying some of the critical components of the host response, mainly because of the use of efficient molecular tools. This review examines some of the components of the innate immune response of drosophila, an insect that has served as an exceptionally good experimental model for studying non-self recognition processes and immune cell signaling mechanisms. Topics considered in this review include hematopoiesis, proliferation and adhesion of hemocytes, melanogenesis and associated cytotoxic molecules, and the genetic aspects of the host-parasitoid interaction.

关键词： cytotoxic molecules hemocyte innate immunity melanogenesis parasitoid,resistance genes

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Evaluation of acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. in wistar rats

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Journal of Integrative Medicine 2018年第5期16卷 335-341页

作者： Jeremiah Oshiomame Unuofin Gloria Aderonke Otunola anthony Jide Afolayan Medicinal Plants and Economic development Research Centre Department of BotanyUniversity of Fort Hare

Objective： This study investigated the acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. （AEVM） in rats for evaluating its safety profile. Methods： AEVM for the acute （2000 and 5000 mg/kg） and subacute （200, 400 and 600 mg/kg） toxicity studies was administered orally to rats according the guidelines 425 and 407 of Organization for Economic Cooperation and development, respectively. Food and water intake as well as body and organ weight of animals were recorded. Signs of toxicity were assessed, and hematological, biochemical and histopathological analyses were performed. Results： In the acute toxicity study, a single dose of the aqueous extract at 2000 or 5000 mg/kg caused no mortality in the animals, suggesting that the median lethal dose is greater than 5000 mg/kg. In the subacute toxicity study, administration of the extract for 28 d, at all doses, caused no significant changes in the body weights or organ weights of rats in the treated groups when compared with the control group. In addition, hematological and biochemical parameters also revealed no toxic effects of the extract on rats. Histological sections of the heart, liver and kidney from test animals show.d no signs of degen- eration. Conclusion： These results show.d that AEVM at dosage levels up to 600 mg/kg is nontoxic and could also offer protection on some body tissues. AEVM could, therefore, be considered safe.

关键词： Vemonia mespilifolia Less Biochemical parameters Acute toxicity Hematological parameters Subacute toxicity

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A theoretical framework for improved fire suppression by linking management models with smart early fire detection and suppression technologies

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Journal of Forestry Research 2024年第5期35卷 1-13页

作者： Li Meng Jim O’Hehir Jing Gao Stefan Peters anthony Hay University of South Australia AdelaideSAAustralia Esk Spatial InvermayTASAustralia

Bushfires are devastating to forest managers,owners,residents,and the natural *** tech-nological advances indicate a potential for faster response times in terms of detecting and suppressing ***,to date,all these technologies have been applied in *** paper introduces the latest fire detection and sup-pression technologies from ground to *** operations research method was used to assemble these technologies into a theoretical framework for fire detection and *** framework harnesses the advantages of satellite-based,drone,sensor,and human reporting technologies as well as image processing and artificial intelligence machine *** study concludes that,if a system is designed to maximise the use of available technologies and carefully adopts them through complementary arrangements,a fire detection and resource suppression system can achieve the ultimate aim:to reduce the risk of fire hazards and the dam-age they may cause.

关键词： Forest fire Resource suppression Smart fire detection and suppression system Forest fire management Holistic system

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An Inchworm-inspired Robot Based on Modular Body, Electronics and Passive Friction Pads Performing the Two-anchor Crawl Gait

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Journal of Bionic Engineering 2018年第5期15卷 820-826页

作者： Flavio Moreira anthony Abundis Michael Aguirre Justin Castillo Pranav A. Bhounsule Robotics and Motion Laboratory Department of Mechanical Engineering The University of Texas at San Antonio One UTSA Circle San Antonio rX78249 USA

we have created an inchworm robot capable of the two-anchor crawl gait on level ground and inclined plane. The main novelty is in the design of the inchworm：（1） three-part body that is 3d printed and actuated by two servo motors to allow a looping and lengthening action, （2） passive friction pads to anchor the feet, each of which may be disengaged using a servo motor actuated lever arm, and （3） modular body and electronics. The robot is about 2 feet （61 cm） in length, has a mass of about 4 kg, and uses an open-loop controller to achieve steady crawling gait. The inchworm robot achieved a speed of 2.54 *** on level ground as well as on an incline plane of 19~. The energy usage as measured by the Mechanical Cost of Transport （a non-dimensional number defined as the energy used per unit weight per unit distance moved） is 3.34. Our results indicate that simple robotic designs that copy the basic features of natural organisms provide a promising alternative over conventional wheeled robots.

关键词： inchworm bioinspiration two-anchor crawl gait 3d printing sliding locomotion cost of transport

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Vegetation structure,dominance patterns and height growth in an Afromontane forest,Southern Africa

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Journal of Forestry Research 2020年第2期31卷 453-462页

作者： Sylvanus Mensah anthony Egeru Achille Ephrem Assogbadjo Romain GleleKakai Laboratoire de Biomathematiques et d’Estimations Forestieres Facultedes Sciences AgronomiquesUniversite d’Abomey-Calavi04 BP 1525 CotonouBenin Regional Universities Forum for Capacity Building in Agriculture Makerere UniversityP.O Box 16811WandegeyaKampalaUganda Laboratoire d’Ecologie Appliquee Facultedes Sciences AgronomiquesUniversite d’Abomey-Calavi03 BP 1974 CotonouBenin

Information on forest structure is fundamentally important to track successional vegetation dynamics for efficient forest *** study reports on vegetation characteristics,dominance patterns and species height growth in a northern mistbelt forest type in South *** alpha-diversity indices(species richness and Shannon-weiner diversity),structural vegetation parameters(tree density and basal area),and species importance value index were *** class distribution and height-diameter allometry were further examined for the overall stand and most important *** densities(472.0±43.5 and 605.3±28.1 trees ha^-1 for C 5 cm to\10 cm and C 10 cm dbh(diameter at breast height)classes,respectively)and basal area values(1.99±0.19 and 48.07±3.46 m^2 ha^-1,respectively)are comparable to other Afromontane forests in East *** overall stand show.d an inverted-J shaped distribution pattern which is a typical feature of stand size class distribution in most natural *** ecologically important species also exhibited an inverted-J shaped distribution pattern,suggesting good regeneration and recruitment *** were significant differences in species on height,reflecting species-specific height growth patterns,possibly a result of intrinsic growth potential and competitive *** present study suggests that conservation and management policies,including protection of surrounding land uses against fire,contribute to maintaining a successful recovery of these ***,it should be noted that these forests may be experiencing relatively slow.dynamic flux as a result of the overmature state of some trees with several years under relatively strict protection.

关键词： diversity Population structure Species composition Size class distribution

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Consistent habitat preference underpins the geographically divergent autumn migration of individual Mongolian common shelducks

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Current Zoology 2020年第4期66卷 355-362页

作者： Fanjuan MENG Xin wANG Nyambayar BATBAYAR Tseveenmyadag NATSAGdORJ Batmunkh dAVAASUREN Iderbat dAMB Lei CAo anthony dFox State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBejing 10085China University of Chinese Academy of Sciences Bejing 10049China wildife Science and Conservation Center of Mongolia Undram Plaza 404 tootUlaanbaatar 210351Mongolia department of Bioscience Aarhus UniversityKalsRande8410Denmark

while many avian populations follow narrow,well-defined"migratory corridors,"individuals from other populations undertake highly divergent individual migration routes,using w.dely dispersed stopover sites en route between breeding and wintering areas,although the reasons for these differences are rarely *** combined individual GPS-tracked migration data from Mongolian-breeding common shelduck Tadorna tadorna and remote sensing datasets,to in-vestigate habitat selection at inland stopover sites used by these birds during dispersed autumn migration,to explain their divergent migration *** used generalized linear mixed models to investigate population-level resource selection,and generalized linear models to investigate stopover-sit-level resource *** population-level model show.d that water recurrence had the strongest positive effect on determining birds'occupancy at staging sites,while cultivated land and grassland land cover type had strongest negative effects;effects of other land cover types were negative but weaker,particularly effects of wwater seasonality and presence of a human foot-print,which were positive but weak or non-significant,*** stopover-site-level models show.d variable resource selection patterns,the variance partitioning and cross-prediction AUC scores corroborated high inter-individual consistency in habitat selection at inland stopover sites during the dispersed autumn *** results suggest that the geographically w.de-spread distribution(and generally rarity)of suitable habitats explained the spatially divergent autumn migrations of Mongolian breeding common shelduck,rather than the species showing flexible autumn staging habitat occupancy.

关键词： common shelducks habitat selection individual variation resource selection function

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