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Adaptation to a novel host and performance trade-off in host-generalist and host-specific insect ectoparasites

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Insect science 2022年第2期29卷 567-580页

作者： irina s.khokhlova Luther van der Mescht Elizabeth M.Warburton Nadezhda A.stavtseva Boris R.Krasnov Wyler Department of Dryland Agriculture French Associates Institute for Agriculture and Biotechnology of DrylandsJacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede Boqer CampusMidreshet Ben-GurionIsrael Mitrani Department of Desert Ecology Swiss Institute for Dryland Environmental and Energy ResearchJacob Blaustein Institutes for Desert ResearchBen-Gurion University of the NegevSede Boqer CampusMidreshet Ben-GurionIsrael Clinvet International Center for the Ecology of Infectious Diseases Odum School of EcologyUniversity of Georgia

We investigated the performance trade-offs of fleas(siphonaptera)while adapting to a novel host using two host generalists(Xenopsylla conformis and Xenopsylla ramesis)and one host specialist(Parapulex chephrenis)maintained on their principal hosts(Meriones crassus for Xenopsylla and Acomys cahirinus for ***).We asked whether,over generations,(i)a host generalist may become a specialist by evolving the ability to exploit a novel host and losing the ability to exploit an original host and(ii)a host specialist can become a generalist by evolving the ability to exploit a novel host without losing the ability to exploit an original *** established an experimental line of each species on a novel host(Acomys russatus for Xenopsylla and *** for ***)and maintained this line on this host during 23 *** compared reproductive performance of progenitors of each line and their descendants when they exploited either original or novel host in terms of egg number and size,hatching success,offspring production,and offspring *** found changes in performance over generations in female offspring size *** conformis demonstrated a tendency to become a host specialist(increased performance on the novel host with a concomitant decreased performance on the original host),whereas *** demonstrated a tendency to become a host generalist(increased performance on the novel host without a concomitant decreased performance on the original host).We conclude that the probability of generalist to specialist transition,and vice versa,is context-dependent and varies between species.

关键词： experimental evolution fleas generalist performance rodents specialist

Iron(III)-Mediated AGET ATRP of Methyl Methacrylate in the Absence of Additional Ligand

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Open Journal of Polymer Chemistry 2012年第3期2卷 99-104页

作者： svetlana A. Bulgakova Evgeniya s. Volgutova irina E. khokhlova University of Nizhny Novgorod Nizhny Novgorod Russia

The atom transfer radical polymerization on the mechanism of activator generation by electron transfer (AGET ATRP) of methyl methacrylate (MMA) in N,N-dimethylformamide (DMF) in the presence of the catalytic systems, namely, CCl4-FeCl3-1-acetyl-2-phenylhydrazine (APH) and CCl4-FeCl3-ascorbic acid (AA) is reported. The living feature of this process was confirmed by obtaining well-defined polymers with controlled molecular weight, narrow molecular weight distribution, and a chain-extension experiment. Both reducing agents, an APH as well as an AA, possess the equal kinetic activitis.

关键词： Atom Transfer Radical Polymerization Methyl Methacrylate Iron Ligand

Magnesium alloy AZ63A reinforcement by alloying with gallium and using high-disperse ZrO_(2) particles

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Journal of Magnesium and Alloys 2016年第4期4卷 265-269页

作者： J.khokhlova M.Khokhlov V.synyuk E.O.Paton Electric Welding Institute NASUKievUkraine

The aim of this work was to obtain an experimental magnesium alloy by remelting standard AZ63A alloy with addition of gallium ligatures and ZrO_(2) *** allowed reinforcement of alloy and increase its hardness and Young’s *** chemical analysis of this alloy shows two types of structures which are evenly distributed in *** we can conclude that reinforcing effect is the result of formation of intermetallic phase Mg_(5)-Ga_(2).

关键词： Magnesium Gallium Zirconium dioxide Alloying Reinforcement

Peculiarities of forming diffusion bimetallic joints of aluminum foam with a monolithic magnesium alloy

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Journal of Magnesium and Alloys 2016年第4期4卷 326-329页

作者： M.Khokhlov D.Ishchenko J.khokhlova The E.O.Paton Electric Welding Institute of National Academy of sciences of Ukraine Ukraine

The work is carried out to determine an optimal method to obtain the welded bimetallic joints of monolithic Mg-alloy with porous Al-alloy using gallium as chemical activator and heating up to 300 ℃ by two different methods:long-term in vacuum oven and short-term without vacuum by passing of low voltage *** is no microstructure change in Al-foam but indentation test records the negligible reduction of the mechanical *** showed the crystallization of two types of Mg_(5)Ga_(2) and Mg_(2)Ga inter-metallic phases in the wavy uneven diffusion zone on Mg-alloy side with significant increase of micro-hardness and Young’s *** narrow depth of the diffusion zone takes place in joints by short-term heating,so this method is more applicable for welding of monolithic and porous alloys at chemical activation using gallium.

关键词： Diffusion Welding Bimetallic Aluminum foam Magnesium alloy

Transformation Pathway of Carbonate Pedofeatures Based on Their Micromorhology and Carbon Isotope Data in the Northern Caucasus Region,Russia

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Journal of Mountain science 2009年第2期6卷 139-146页

作者： khokhlova O.s. Kouznetsova A.M. Khokhlov A. A. Institute of Physicochemical and Biological Problems of soil science Russian Academy of Sciences ul.Institutskaya 2 Pushchino Moscow region 142290 Russia Laboratory of Electron Microscopy Biological Faculty Moscow State UniversityMoscow 119899 Russia Institute of Cell Biophysics Russian Academy of Sciences ul.Institutskaya 3 Pushchino Moscow region 142290 Russia

Carbonate pedofeatures (CPs) in a chronosequence of paleosols buried under kurgans in the Northern Caucasus region of Russia in a period from the end of the 4th to the middle of the 5th centuries AD (It seams that there is no time left) were studied by using a set of morphological and isotopic methods. The CPs in chernozem-type soils of Russia are usually represented by crystallomorphic calcite whereas the non-segregated carbonates occurred at the same horizons-by collomorphic one. Those two morphotypes of calcite have the differences in elemental composition and isotopic composition of carbon and, hence, should have different origins-from true and colloidal solutions, respectively. The same differences including radiocarbon age have been revealed for pseudomycelium of the ABca horizon of the youngest paleosols as compared with the same CPs of other paleosols in the chronosequence studied. Our assumption is that it was succeeded in finding that the pseudomycelium right away after its precipitation from a colloidal solution migrated from the lower soil horizons to the surface horizons during the periods of climatic aridization. After a short time interval (not more than 25-50 years) collomorphic calcite in the pseudomicelium of the yongest paleosols mentioned above will likely become by "usual" acicular calcite.

关键词： Carbonate pedofeature chernozems kurgans holocene paleosol set of morphological andisotopic method

shining the shortest flashes of light on the secret life of electrons

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Advanced Photonics 2023年第6期5卷 5-7页

作者： Margarita khokhlova Emilio Pisanty Amelle Zaïr King’s College London Department of PhysicsLondonUnited Kingdom

Ever since the invention of laser pulses,^(1–5)one of the key directions for the development of laser technology has been the creation of ever shorter pulses of *** the past sixty years,improvements in technology have pushed pulse durations down from nanoseconds through picoseconds to femtoseconds,giving us access to time-resolved studies of molecular nuclear motion and chemical reactions.^(6)Just in time for the 59th birthday of the standard(sI)prefixes“femto”and“atto,”^(7)the 2023 Nobel Prize in Physics was awarded to the latest landmark in this effort:the generation of attosecond pulses of light,^(8–10)which opens a window to the most fundamental timescale of the world around us–the timescale of electrons moving inside atoms,molecules,and condensed matter.

关键词： light shortest flash

Iron(III)-Mediated AGET ATRP of Methyl Methacrylate in the Absence of Additional Ligand

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Open Journal of Polymer Chemistry（高分子化学期刊） 2012年第3期

作者： svetlana A. Bulgakova Evgeniya s. Volgutova irina E. khokhlova

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应用生物吸附剂修复石油污染土壤(英文)

山东科学 2010年第6期23卷 1-4页

作者： L.khokhlova V.strelko A.Khokhlov V.Lapko 王加宁乌克兰国家科学院吸收与生态吸收问题研究所山东省应用微生物重点实验室山东省科学院生物研究所

采用生物碳吸附剂（植物性碳吸附材料表面固定本土石油氧化微生物）对污染土壤中的不同石油组分降解性能进行了研究。结果表明,10~14天后石油生物降解率达到40%~50%,30~40天后石油污染物降解率超过90%,土壤中石油烃含量下降至2%~3%,剩... 详细信息

采用生物碳吸附剂（植物性碳吸附材料表面固定本土石油氧化微生物）对污染土壤中的不同石油组分降解性能进行了研究。结果表明,10~14天后石油生物降解率达到40%~50%,30~40天后石油污染物降解率超过90%,土壤中石油烃含量下降至2%~3%,剩余的石油污染物中,饱和分与芳香分含量明显降低,而胶质与沥青质含量显著增加。在乌克兰与俄罗斯油田采油与炼油企业进行了生物碳吸附剂的示范试验,结果表明,该吸附剂对土壤中的石油污染物具有较高的降解率,结果令人满意。

关键词：吸附降解石油污染土壤