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Potential adaptation of a Q biotype whitefly population from poinsettia to field crops

Insect Science 2011年第6期18卷 719-728页

作者： Xiangshun Hu Timothy J. Dennehy Xinzhi Ni Huiyan Zhao Robert l. Nichols Xianchun li College of Plant Protection NorthwestA ＆ F University Yangfing Shaanxi Province China Department of Entomology and BI05 Institute University of Arizona Tucson Arizona USDA-ARS Crop Genetics and Breeding Research Unit Tifton Georgia Cotton Incorporated Cary North Carolina USA

The invasive Q biotype whitefly was first detected in the US on poinsettia in 2004 and is still not a pest outside of greenhouse environments in the US. To assess the potential for the establishment of the Q biotype on field crops, population cage experiments were conducted to compare the performance of a poinsettia-derived Q population named P＇06 on poinsettia and six field crops （alfalfa, tomato, melon, cotton, cowpea and cabbage）. P＇06 adults reared on poinsettia as nymphs laid eggs on all six field crops. Significantly more eggs were laid on alfalfa, tomato, melon and cotton than on cabbage, cowpea and poinsettia. These eggs hatched and the nymphs developed to adults on the six field crops. Relative to poinsettia, whitefly survival was similar on cowpea, alfalfa, tomato and cabbage, but significantly higher on cotton and melon. Moreover, P＇06 had significantly shorter development times from egg to adult on cotton, melon, cowpea, tomato and alfalfa than they did on poinsettia. However, the F1 adults raised on the six field crops had significantly shorter lifespans and laid 11- to 18-fold fewer eggs than did the F1 adults raised on poinsettia. Taken together, while P＇06 may have some potential to establish on field crops, the shorter lifespans and extremely low fectmdities of the F1 adults raised on the six field crops suggests that P＇06 is incapable of rapidly adapting to them. Poor adaptation to field crops may explain, at least partially, why the Q biotype has not established in the US field system.

关键词： Bemisia tabaci host adaptation life history traits population establishment,Q-biotype.

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Changes in soil properties under Eucalyptus relative to Pinus massoniana and natural broadleaved forests in South China

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Journal of Forestry Research 2018年第5期29卷 1299-1306页

作者： Shuangshuang Chu Douglass F.Jacobs Joshua l.Sloan li Xue Daoming Wu Shucai Zeng College of Forestry and landscape Architecture South China Agricultural University Department of Forestry and Natural Resources Purdue University

The ecological effects of eucalypt plantations（EPs） have garnered increasing *** understand their effect on soil quality at a landscape scale,and to determine whether soil quality parameters differ due to different stand types,we evaluated soil characteristics in twenty-one groups of EPs,Pinus massoniana ***（PMPs） and natural broadleaved forests（NBFs）across Guangdong Province,*** the physical characteristics of soil hydrology and the properties of soil nutrients in A and B horizons were *** showed that,compared to NBFs,EPs and PMPs produced a shallower litter layer,reduced canopy density,higher soil bulk density,significantly lower total porosity,non-capillary porosity,total water volume,and hygroscopic water in the A horizon（P〈0.05）.Moreover,total N,available K,and soil organic carbon（SOC） in EPs and PMPs were significantly lower than in *** and PMPs did not differ significantly in N,P or K content,but PMPs had significantly lower SOC and boron in the A horizon than *** p H and poor capacity to buffer acidification generally occurred in all cover *** EPs and PMPs showed a decline in soil properties relative to NBFs,but EPs and PMPs exhibited no significant *** results indicate that actions are needed to ameliorate the potential negative effects on soil quality in forestry plantations.

关键词： Eucalyptus Pinus massoniana Plantations Soil organic matter Soil acidification Moisture retention capacity

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PARAllEl STABIlIZATION

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 29-38页

作者： J. l. lIONS(College de france,3,red’Ulm,75231 Paris Cedex 05,France) Collége de France 3 rue d'Ulm 75231 Paris Cedex 05 France

A new algorithm for the stabilization or (possibly turbulent, chaotic) distributed systems,governed by linear or non linear systems of equations is *** SPA (Stabilization Parallel Algorithm) is based on a systematic parallel decompositionof the problem (related to arbitrarily overlapping decomposition of domains) and on a *** is presented here for the case of linear parabolic equations, with distributed or boundarycontrol. It extends to practically all linear and non linear evolution equations, as it will bepresented in several other publications.

关键词： SPA linear parabolic equation Distributed system

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Depression among elderly Chinese-Canadian immigrants from China's Mainland

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Chinese Medical Journal 2004年第5期117卷 677-683页

作者： Daniel W.l.lai University of Calgary

Background This study examined the prevalence of depressive symptoms among elderly immigrants from China's Mainland to Canada and the impact of various psychosocial factors as predictors of the number of depressive symptoms reported by the elderly Chinese immigrants Methods The participants were 444 elderly immigrants who migrated from China's Mainland to Canada They were a part of a random sample of 2272 elderly Chinese living in the communities and took part in a face-to-face interview to answer questions in an orally administrated questionnaire The depressive symptoms of the participants were measured by a Chinese version of the Geriatric Depression Scale Data obtained from the 444 elderly Chinese immigrants was analyzed to assess the impact of various psychosocial factors on the number of depressive symptoms that they reported Results The findings indicated that 23 2% of the elderly immigrants were assessed to have some depressive symptoms When other predicting variables were adjusted, elderly immigrants with more chronic illnesses, less positive attitude towards ageing, poorer physical health, less adequate financial situation, lower level of ethnic identification as Chinese, more service barriers, lower level of life satisfaction, shorter length of residency in Canada and those who lived alone tended to have more depressive symptoms Conclusions The findings indicate that the prevalence rate of depressive symptoms among our elderly immigrant sample is higher than the one reported in a general elderly population While further research is recommended to examine the reasons for such a difference, culturally appropriate health services, including health promotion programs, should be promoted to reduce mental health disparities

关键词： elderly Chinese depression elderly immigrants mental health Geriatric Depression Scale

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Vacuum promotes metabolic shifts and increases biogenic hydrogen production in dark fermentation systems

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 513-521页

作者： Haifa RAJHI Daniel PUYOl Mirna C. MARTiNEZ Emiliano E. DlAZ Jose l. SANZ Department of Molecular Biology University Autonoma of Madrid Madrid 28049 Spain Section of Chemical Engineering University Autonoma of Madrid Madrid 28049 Spain MYGEN laboratory Cantoblanco Madrid 28049 Spain

The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater （four synthetic media, two industrial waste- water, and one domestic effluent） and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogen-producing bacteria, such as Clostridium, and promoted the dominance of acetoclasticover hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the COD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields.

关键词： dark fermentation biohydrogen wastewaters vacuum

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Statistical improvement in detection level of gravitational microlensing events from their light curves

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Research in Astronomy and Astrophysics 2018年第4期18卷 43-58页

作者： Ichsan Ibrahim Hakim l.Malasan Chatief Kunjaya Anton Timur Jaelani Gerhana Puannandra Putri Mitra Djamal Department of Astronomy Institute of Technology Bandung Bandung Indonesia Department of Physics Department of Astronomy Institute of Technology Bandung Bandung Indonesia Bosscha Astronomical Observatory Department of Astronomy Institute of Technology Bandung LembangIndonesia Department of Informatics STMIK-Indonesia Mandiri Bandung Indonesia Universitas Ma Chung Malang Indonesia Faculty of Shariah Institut Agama Islam Ternate Ternate North Molucca Indonesia Astronomical Institute Tohoku University Sendai Japan

In astronomy,the brightness of a source is typically expressed in terms of ***,the magnitude is defined by the logarithm of received *** relationship is known as the Pogson *** received flux with a small signal to noise ratio（S/N）,however,the formula gives a large magnitude *** investigate whether the use of Inverse Hyperbolic Sine function（hereafter referred to as the Asinh magnitude）in the modified formulae could allow for an alternative calculation of magnitudes for small S/N flux,and whether the new approach is better for representing the brightness of that *** study the possibility of increasing the detection level of gravitational microlensing using 40 selected microlensing light curves from the 2013 and 2014 seasons and by using the Asinh *** data of the selected events are obtained from the Optical Gravitational lensing Experiment（OGlE）.We found that utilization of the Asinh magnitude makes the events brighter compared to using the logarithmic magnitude,with an average of about 3.42×10^（-2）magnitude and an average in the difference of error between the logarithmic and the Asinh magnitude of about 2.21×10（-2）*** microlensing events OB140847 and OB140885 are found to have the largest difference values among the selected *** a Gaussian fit to find the peak for OB140847 and OB140885,we conclude statistically that the Asinh magnitude gives better mean squared values of the regression and narrower residual histograms than the Pogson *** on these results,we also attempt to propose a limit in magnitude value for which use of the Asinh magnitude is optimal with small S/N data.

关键词： gravitational lensing micro — methods data analysis

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An Experi mental Study on Wave-Induced Dynamic Stresses in Seabed

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China Ocean Engineering 2006年第1期20卷 27-44页

作者： S.C.Chang l.K.Chien J .G.lin Y.F.Chiu Department of Harbor and River Engineering National Taiwan Ocean University Taiwan China Harbor and Marine Technology Center Taiwan China

A series of hydraulic model tests with horizontal movable seabed under regular wave actions have been carried out to investigate the dynamic interactions between water waves and seabed soil. Seabed dynamic stresses from experiments are, tound to differ from theoretical resuhs. The response of p0 in permeable seabed has a small decay and phase shift to the nonlinear wave actions, and the dynamic stresses, σs/p0, σh/p0 and u/p0, contain different phase shift characteristics. Such phenomena will strongly affect the dynamic stress path in seabed. If the phase shifts of σs. and σh are neglected, the stress path will become a straight line; otherwise, it will become an elliptical curve. In phase shift cases, the long axis of the p - q diagram will be shortened when the depth increases, and the short axis will become longer when the phase shift increases. For the p＇ - q＇ diagram, the larger the phase lag of u, the longer the short axis. Relative results offer useful information for the analysis of seabed stability.

关键词： wave-induced dynamic stresses movable seabed hydraulic model test stress path

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Association of Varroa destructor females in multiply infested cells of the honeybee Apis mellifera

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Insect Science 2019年第1期26卷 128-134页

作者： Alexis l.Beaurepaire James D.Ellis Klemens J.Krieger Robin F.A.Moritz Institut for Biologie Martin-Luther-University Halle-WittenbergHalle a.d.SaaleGermany UR 406 Abeilles et Environnement INRACentre de Recherche Provence-Alpes-Cote d'AzurAvignonFrance Entomology &Nematology Department University Florida GainesvilleFloridaUSA Bayer Animal Health GmbH LeverkusenGermany Department of Zoology and Entomology University of PretoriaPretoriaSouth Africa

The genetic diversity of Varroa destructor (Anderson &Trueman)is limited outside its natural range due to population bottlenecks and its propensity to *** light of the arms race between *** and its honeybee (Apis mellifera l.)host, any mechanism enhancing population admixture of the mite may be *** way that admixture can occur is when two genetically dissimilar mites coinvade a brood cell, with the progeny of the foundresses *** determined the relatedness of 393 pairs of *** foundresses,each pair collected from a single bee brood cell (n =five colonies).We used six microsatellites to identify the genotypes of mites coinvading a cell and calculated the frequency of pairs with different or the same *** found no deviation from random coinvasion,but the frequency of cells infested by mites with different genotypes was *** rate of recombination,coupled with a high transmission rate of mites,homogenized the allelic pool of mites within the apiary.

关键词： Apis mellifera host-parasite coevolution inbreeding avoidance mating behavior population genetics Varroa destructor

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A framework on task configuration and execution for distributed geographical simulation

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International Journal of Digital Earth 2021年第9期14卷 1103-1125页

作者： Fengyuan Zhang Min Chen Ming Wang Zihuan Wang Shuo Zhang Songshan Yue Yongning Wen Guonian lü Key laboratory of Virtual Geographic Environment(Ministry of Education of PRC) Nanjing Normal UniversityNanjingPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingPeople’s Republic of China State Key laboratory Cultivation Base of Geographical Environment Evolution(Jiangsu Province) NanjingPeople’s Republic of China

Geographical simulation is a popular method in geographical and environmental *** models developed to address geographic and environmental issues are distributed ***,due to the lack of portals,these models are still difficult to invoke for geographical simulations in open web *** study designs and develops a framework to assemble service-oriented models from volunteers distributed worldwide for geographical simulations on the *** framework consists of three layers(task layer,data exchange layer,and model execution layer)that establish a network of serviceoriented locally shared models and simulation tasks for user *** the help of such a framework,users can configure simulation tasks and invoke suitable models shared worldwide for geographical *** article provides an application of the distributed simulation of gross primary production(GPP)by the Biome-BioGeochemical Cycles(BGC)model in *** application shows that the framework can be beneficial for model assembly from volunteers’computers and distributed simulation tasks that are run for geographical and environmental issues,which can be applied to Digital Earth initiatives.

关键词： Geo-analysis models model service sharing distributed simulation volunteer computing Open Geographic Modeling and Simulation(OpenGMS)

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Experimental results of the tribology of aluminum measured with a pin-on-disk tribometer: Testing configuration and additive effects

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Friction 2016年第2期4卷 124-134页

作者： S.M.H.AHMER l.S.JAN M.A.SIDDIG S.F.ABDUllAH Department of Physics GS Faculty Yanbu University College Yanbu al Sinayiah 41912 Kingdom of Saudi Arabia Department of Physics Faculty of Science and Technology al Neelain University Khartoum 11111 Sudan Mechanical Engineering Department UNITEN Kajang 43009 Malaysia

The friction coefficient, wear rate, and wear coefficient of the aluminum metal surface were measured at room temperature (≈300 K) with a pin-on-disk machine at a fixed load of 196.2 N. Two different testing configurations were adopted: (1) aluminum pin vs. Helix oil-on-steel disk (AHS) and (2) aluminum pin vs. 10% Polytron plus 90% helix oil-on-steel disk (APS). In the AHS configuration, the wear of the aluminum surface was found to be approximately 70 μm; however, in the APS configuration the wear dropped to 20 μm, revealing a marked decrement of one-third of the wear of aluminum. The volume wear rate of the metal in the unaided Helix oil was estimated to be 1.28×10–3 mm3/min. The additive minimized the volume wear rate of the aluminum metal by orders of magnitude to 6.08×10–5 mm3/min. Similarly, the wear coefficient of the aluminum pin, calculated in the AHS configuration, rendered a value of 1.27×10–10 m2/N. In the APS configuration, the same parameter was 4.22×10–11 m2/N, that is to say, an order of magnitude lower than the preceding value. The observed coefficient of friction for aluminum is 0.012 in Helix oil and falls to a remarkably lower value of 0.004 through the Polytron additive. The experimental findings demonstrate that Polytron additive substantially lessens the wear of the aluminum surface; in effect, the wear coefficient and the wear rate decline linearly. This singularity may be linked to the ability of Polytron to impregnate the crystal structure of the metal due to its ionic character and the consequent adherence to the metallic surface as a hard surface layer.

关键词： antiwear Polytron additive aluminum metal lubrication friction

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