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Soil Ecology Letters 2022年第4期4卷 444-453页

作者： Amit Kumar Evgenia Blagodaskaya michaela A.Dippold vicky m.Temperton Institute of Ecology Faculty of SustainabilityLeuphana University Lüneburg21335LuneburgGermany Department of Soil Ecology Helmholtz Center for Environmental Research-UFZ Halle06120Halle(Saale)Germany Agro-Technology Institute RUDN University117198MoscowRussia Biogeochemistry of Agroecosystems University of GoettingenBuesgenweg 237077GoettingenGermany

Less attention has been given to soil enzymes that contribute to beneficial rhizosphere interactions in intercropping ***,we performed a field experiment by growing faba bean,lupine,and maize in mono and mixed cultures in a moderately fertile *** measured shoot biomass and the kinetic parameters(maximal velocity(V max)and michaelis-constant(K m))of three key enzymes in the rhizosphere:Leucine-aminopeptidase(LAP),β-1,4-N-acetylglucosaminidase(NAG),and phosphomonoesterase(PHO).Faba bean benefitted in mixed cultures by greater shoot biomass production with both maize and lupine compared to its expected biomass in ***,LAP and NAG kinetic parameters were less responsive to mono and mixed cultures across the crop *** contrast,both the V max and K m values of PHO increased in the faba bean rhizosphere when grown in mixed cultures with maize and lupine.A positive relative interaction index for shoot P and N uptake for faba bean showed its net facilitative interactions in the mixed ***,these results suggest that over-productivity in intercropping is crop-specific and the positive intercropping effects could be modulated by P *** argue that the enzyme activities involved in nutrient cycling should be incorporated in further research.

关键词： Enzyme kinetic parameters Phosphorus mobilization Nitrogen fixation Niche complementarity Biomass increase Relative interaction index

Sonicating bees demonstrate flexible pollen extraction without instrumental learning

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Current Zoology 2019年第4期65卷 425-436页

作者： Callin m. Switzer avery L. Russell Daniel R. Papaj Stacey A. Combes Robin Hopkins Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA Arnold Arboretum Harvard University Boston MA USA Department of Ecology and Evolutionary Biology University of Arizona Tucson AZ USA Department of Neurobiology Physiology and Behavior University of California at Davis Davis CA USA Department of Biology and eScience Institute University of Washington Seattle WA USA Department of Biological Sciences University of Pittsburgh Pittsburgh PA USA

Pollen collection is necessary for bee survival and important for flowering plant reproduction, yet if and how pollen extraction motor routines are modified with experience is largely unknown. Here, we used an automated reward and monitoring system to evaluate modification in a common pollen-extraction routine, floral sonication. Through a series of laboratory experiments with the bumblebee, Bombus impatiens, we examined whether variation in sonication frequency and acceleration is due to instrumental learning based on rewards, a fixed behavioral response to rewards, and/or a mechanical constraint. We first investigated whether bees could learn to adjust their sonication frequency in response to pollen rewards given only for specified frequency ranges and found no evidenee of instrumental learning. However, we found that absenee versus receipt of a pollen reward did lead to a predictable behavioral resp on se, which depe nded on bee size. Fin ally, we found some evide nee of mechanical con straints, in that flower mass affected sonication acceleration (but not frequency) through an interaction with bee size. In generalz larger bees showed more flexibility in sonication frequency and acceleration, potentially reflecting a size-based constraint on the range over which smaller bees can modify frequency and accelerati on. Overall our results show that although bees did not display instrumental learning of sonication frequency, their sonication motor routine is nevertheless flexible.

关键词： Bombus impatiens buzz pollination foraging innate behavior learned behavior Solanum

Continuous conversion of methanol to higher hydrocarbons at ambient pressure

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Journal of Natural Gas Chemistry 2010年第5期19卷 461-462页

作者： William W.Porterfield Gordon m.Zrelak L.avery moncure matthew D.Huff Hampden-Sydney College Pennsylvania State University University Park UNC-Charlotte

An iodozincate ionic liquid solvent and catalyst is used to convert methanol continuously to a wide variety of hydrocarbons at atmospheric pressure.

关键词： methanol conversion zinc iodide hydrocarbon formation

Predicting superhard materials via a machine learning informed evolutionary structure search

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npj Computational materials 2019年第1期5卷 352-362页

作者： Patrick avery Xiaoyu Wang Corey Oses Eric Gossett Davide m.Proserpio Cormac Toher Stefano Curtarolo Eva Zurek Department of Chemistry State University of New York at BuffaloBuffaloNY 14260-3000USA Department of mechanical Engineering and materials Science Duke UniversityDurhamNC 27708USA Dipartimento di Chimica Universitàdegli Studi di MilanoVia Golgi 1920133 MilanoItaly Samara Center for Theoretical materials Science(SCTmS) Samara State Technical UniversityMolodogvardeyskaya St.244443100 SamaraRussia Center for Autonomous materials Design Department of Mechanical Engineering and Materials ScienceDuke UniversityDurhamNC 27708USA

The computational prediction of superhard materials would enable the in silico design of compounds that could be used in a wide variety of technological ***,good agreement was found between experimental Vickers hardnesses,Hv,of a wide range of materials and those calculated by three macroscopic hardness models that employ the shear and/or bulk moduli obtained from:(i)first principles via AFLOW-AEL(AFLOW Automatic Elastic Library),and(ii)a machine learning(mL)model trained on materials within the AFLOW *** H^(mL)_(v) values can be quickly estimated,they can be used in conjunction with an evolutionary search to predict stable,superhard *** methodology is implemented in the XTALOPT evolutionary *** crystal is minimized to the nearest local minimum,and its Vickers hardness is computed via a linear relationship with the shear modulus discovered by *** the energy/enthalpy and H^(mL)_(v),Teter are employed to determine a structure’s *** implementation is applied towards the carbon system,and 43 new superhard phases are found.A topological analysis reveals that phases estimated to be slightly harder than diamond contain a substantial fraction of diamond and/or lonsdaleite.

关键词： structure modulus Elastic

male Burmese pythons follow female scent trails and show sex-specific behaviors

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Integrative Zoology 2019年第5期14卷 460-469页

作者： Shannon A.RICHARD Eric A.TILLmAN John S.HUmPHREY michael L.avery m.Rockwell PARKER Department of Biology James Madison UniversityHarrisonburgVirginiaUSA National Wildlife Research Center Florida Field StationU.S.Department of AgricultureGainesvilleFloridaUSA

Animals communicate with potential mates using species-specific signals,and pheromones are powerful sexual signals that modify conspecific behavior to facilitate mate *** the vertebrates,snakes are especially adept in mate searching via chemical trailing,which is particularly relevant given that many snake species are invasive outside their native *** signals used in mate choice are,thus,potentially valuable tools for management of invasive snake *** Burmese python(Python bivittatus)is an invasive snake in the Florida Everglades where it is negatively impacting native *** this study,we sought to:(i)determine if males can follow conspecific chemical trails in a Y-maze;and(ii)describe the mate searching behaviors exhibited by males while *** males consistently followed a single female scent trail in the maze,but when only a male scent trail was present they did not discriminate between the male and blank *** of tongue-flicking,a proxy for chemosensory sampling,was also marginally higher when males were following female versus male scent ***,when both female and male scent trails were simultaneously present in the Y-maze,males did not show a preference for the female arm,although the tongue-flick rate was higher in the female-only trial compared to female versus *** of multiple male behaviors individually and using an ethogram revealed that behaviors were more frequent and complex in the female-only trials compared to male-only *** behavioral trials are needed to determine if an effective pheromonal approach to Burmese python management is possible.

关键词： chemical ecology invasive species pheromone snake trailing

Improved reversed phase liquid chromatographic method with pulsed electrochemical detection for tobramycin in bulk and pharmaceutical formulation

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Journal of Pharmaceutical Analysis 2013年第3期3卷 161-167页

作者： vicky manyanga Ehab Elkady Jos Hoogmartens Erwin Adams Laboratory for Pharmaceutical Analysis Faculteit Farmaceutische Wetenschappen KU LeuvenO&N2 PB 923 Herestraat 49 B-3000 Leuven Belgium Pharmaceutical Chemistry Department Faculty of Pharmacy Cairo University Kasr El-Aini St.Cairo 11562 Egypt

Tobramycin is one of the aminoglycoside antibiotics that lack a UV absorbing chromophore. However, the application of pulsed electrochemical detection （PED） has been used successfully for the analysis of this and similar antibiotics. This work describes an improved liquid chromatographic （LC） method combined with PED, which is able to separate much more impurities than before. Using a Discovery C-18 RP column （250 mm × 4.6 mm i.d., 5 μm）, isocratic elution was carried out with a mobile phase, containing sodium sulfate （35 g/L）, sodium octanesulphonic acid （1 g/L）, tetrahydrofuran （14mL/L） and 0.2 m phosphate buffer pH 3.0 （50 mL/L）. Using these experimental conditions, the limit of quantification （LOQ, S/N= 10） was 5 ng. The linearity was examined in the range LOQ-60 μg/mL and the coefficient of determination was 0.998. The method also proved to be repeatable and the recovery was close to 100%. The influence of the different chromatographic parameters on the separation was investigated by means of an experimental design. The proposed method is useful in quality control of tobramycin drug substances and drug products.

关键词： Liquidchromatography-Pulsed electrochemicaldetection Tobramycin Aminoglycosideantibiotics

Environmental temperatures,physiology and behavior limit the range expansion of invasive Burmese pythons in southeastern USA

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Integrative Zoology 2012年第3期7卷 271-285页

作者： Elliott R.JACOBSON David G.BARKER Tracy m.BARKER Richard mAULDIN michael L.avery Richard ENGEmAN Stephen SECOR College of Veterinary medicine University of FloridaGainesvilleFlorida Vida Preciosa International(VPI) BoerneTexas US Department of Agriculture Wildlife ServicesNational Wildlife Research CenterFort CollinsColorado US Department of Agriculture Wildlife ServicesNational Wildlife Research CenterGainesvilleFlorida Department of Biological Sciences University of AlabamaTuscaloosaAlabamaUSA

A well-established population of Burmese pythons resides in the Everglades of southern *** in part by a report that identified much of southern USA as suitable habitat for expansion or establishment of the Burmese python,we examined the plausibility of this snake to survive winters at sites north of the *** integrated daily low and high temperatures recorded from October to February from 2005-2011 at Homestead,Orlando and Gainesville,Florida;and Aiken,South Carolina,with minimum temperatures projected for python digestion(16℃),activity(5℃)and survival(0℃).mean low and high temperatures decreased northward from Homestead to Aiken and the number of days of freezing temperatures increased *** was impaired or inhibited for 2 months in the Everglades and up to at least 5 months in Aiken,and activity was increasingly limited northward during these *** of overwinter survivorship document that a single bout of low and freezing temperatures results in python *** capacity for Burmese pythons to successfully overwinter in more temperate regions of the USA is seemingly prohibited because they lack the behaviors to seek refuge from,and the physiology to tolerate,cold *** tropical Southeast Asia is the source of the Everglades Burmese pythons,we predict it is unlikely that they will be able to successfully expand to or colonize more temperate areas of Florida and adjoining states due to their lack of behavioral and physiological traits to seek refuge from cold temperatures.

关键词： ambient temperature Burmese python invasion snake thermal tolerance

mojave desert tortoise(Gopherus agassizii)thermal ecology and reproductive success along a rainfall cline

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Integrative Zoology 2015年第3期10卷 282-294页

作者： Annette E.SIEG megan m.GAmBONE Bryan P.WALLACE Susana CLUSELLATRULLAS James R.SPOTILA Harold W.avery Department of Natural Sciences University of Michigan-DearbornDearbornMichiganUSA HDR Plymouth MeetingPennsylvaniaUSA Nicholas School of the Environment Duke University Marine LaboratoryBeaufortNorth CarolinaUSA Stratus Consulting BoulderColoradoUSA Centre for Invasion Biology Department of Botany and ZoologyStellenbosch UniversityPrivate Bag X1Matieland 7602South Africa Department of Biodiversity Earth and Environmental ScienceDrexel UniversityPhiladelphiaPennsylvaniaUSA Department of Biology The College of New JerseyEwingNew JerseyUSA

Desert resource environments(***,food)are tied to limited,highly localized rainfall regimes which generate microgeographic variation in the life histories of ***,enhanced growth rates,reproduction and survivorship are observed in response to increased resource availability in a variety of desert plants and short-lived *** examined the thermal ecology and reproduction of US federally threatened mojave desert tortoises(Gopherus agassizii),long-lived and large-bodied ectotherms,at opposite ends of a 250-m elevation-related rainfall cline within Ivanpah Valley in the eastern mojave Desert,California,*** operative environments in both the upper-elevation,“Cima,”and the lower-elevation,“Pumphouse,”plots corresponded with daily and seasonal patterns of incident solar *** received 22%more rainfall and contained greater perennial vegetative cover,which conferred 5°C-cooler daytime shaded *** a monitored average rainfall year,Cima tortoises had longer potential activity periods by up to several hours and greater ephemeral *** resource availability in Cima was associated with larger-bodied females producing larger eggs,while still producing the same number of eggs as Pumphouse ***,reproductive success was lower in Cima because 90%of eggs were depredated versus 11%in Pumphouse,indicating that predatory interactions produced counter-gradient variation in reproductive success across the rainfall ***-use impacts on deserts(*** energy generation)are increasing rapidly,and conservation strategies designed to protect and recover threatened desert inhabitants,such as desert tortoises,should incorporate these strong ecosystem-level responses to regional resource variation in assessments of habitat for prospective development and mitigation efforts.

关键词： Gopherus agassizii operative environments reproductive ecology resource gradient

SGT1 Is Induced by the Potato virus X TGBp3 and Enhances Virus Accumulation in Nicotiana benthamiana

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molecular Plant 2012年第5期5卷 1151-1153页

作者： Chang-ming Ye vicky Kelly mark Payton martin B. Dickman Jeanmarie Verchot Department of Entomology and Plant Pathology Oklahoma State UniversityStillwaterOK 74078USA Department of Statistics Oklahoma State University StillwaterOK 74078USA Institute for Plant Genomics and Biotechnology Department of Plant Pathology and MicrobiologyTexas A&M UniversityCollege StationTX 77843USA

Dear Editor, Host chaperone proteinsarecritical factors in plant virus infec- tion. One ofthe most commonly identified host factors involved in plant virus infection is Hsp70, which functions in ATP hydroly- sis, protein folding, assembly of protein complexes, and translo- cation between cellular compartments. A comparative study of plant virus infection, including Potato virus X （PVX）, reported that Hsp70 is up-regulated by virus infection and possibly con- tributes to pathogenesis in both Arabidopsis and N. benthami- ana plants （Aparicio et al., 2005）. Cytosolic Hsp70 interacts with the tombusvirus and tymovirus replication complexes （Wang et al., 2009）, the potyvirus coat protein （Hafren et al., 2010）, and closteroviruses encode an HSP70 homolog that functions to enable virus intercellular transport （Agranovsky et al., 1998）.

关键词： LETTERS to the editor NICOTIANA benthamiana POTATO virus X