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Glyphosate Dissipation in Different Soils Under No-Till and Conventional Tillage

Pedosphere 2019年第6期29卷 773-783页

作者： elena OKADA JoséLuis COSTA Francisco BEDMAR Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Balcarce 7620(Argentina Estación Experimental Agropecuaria Balcarce Instituto Nacional de Tecnología Agropecuaria(INTA)Balcarce 7620(Argentina Facultad de Ciencias Agrarias Universidad Nacional de Mar del PlataBalcarce 7620(Argentina

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides on the market. It is used as a weed controller in no-till systems, and it is also applied to various genetically modified crops ( e.g., soybean, corn, and cotton). Although it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from agricultural areas of Argentina under long-term management with no-till (NT) and conventional tillage (CT) practices. There were no differences in dissipation between NT and CT, indicating that the glyphosate-degrading microflora was not modified by the different tillage managements. Moreover, tillage practices did not alter the general soil properties;therefore, glyphosate bioavailability was not affected by NT or CT practice. Forty percent of the applied glyphosate was degraded within the first three days in all soils, indicating a fast initial dissipation rate. However, the dissipation rate considerably decreased over time, and the degradation kinetics followed a bi-exponential (or two-compartment) kinetic model. No differences were found between tillage practices. Dissipation was not related to the microbial activity measured as soil respiration. The fast decrease in the concentration of glyphosate at the beginning of the dissipation study was not reflected in an increase in the concentration of AMPA. The estimated half-lives for glyphosate ranged between 9 and 38 d. However, glyphosate bioavailability decreases over time, as it is strongly adsorbed to the soil matrix. This increases its residence time, which may lead to its accumulation in agricultural soils.

关键词： Aminomethylphosphonic acid Bioavailability Biodegradation Herbicide Metabolite Pesticide Two-compartment kinetic model

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Effect of storage conditions on long-term stability of Ag nanoparticles formed via green synthesis

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1177-1182页

作者： Oksana Velgosova elena Cizmarova Jaroslav Málek Jana Kavulicova Institute of Materials Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia Department of Materials Engineering Faculty of Mechanical Engineering Czech Technical University in Prague Karlovo nám. 13 121 32 Prague 2 Czech Republic Institute of Metallurgy Faculty of Metallurgy Technical University of Kosice Letna 9 042 00 Kosice Slovakia

Spherical Ag nanoparticles(AgNPs) with a diameter of 20 nm or smaller were biologically synthesized using algae Parachlorella kessleri. The effect of storage conditions on the long-term stability of AgNPs was investigated. UV/Vis spectrophotometry, transmission electron microscopy, and dynamic light scattering measurements revealed that the long-term stability of AgNPs was influenced by light and temperature conditions. The most significant loss of stability was observed for the AgNPs stored in daylight at room temperature. The AgNPs stored under these conditions began to lose their stability after approximately 30 d; after 100 d, a substantial amount of agglomerated particles settled to the bottom of the Erlenmeyer flask. The AgNPs stored in the dark at room temperature exhibited better long-term stability. Weak particle agglomeration began at approximately the 100 th day. The AgNPs stored in the dark at about 5℃ exhibited the best long-term stability; the AgNPs stored under such conditions remained spherical, with a narrow size distribution, and stable(no agglomeration) even after 6 months. Zeta-potential measurements confirmed better dispersity and stability of AgNPs stored under these conditions.

关键词： silver nanoparticles stability storage conditions green synthesis Parachlorella kessleri

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Hidden in plain sight:Morphological and phylogenetic evidence for Bouteloua arizonica,a species distinct from Bouteloua aristidoides(Poaceae,Chloridoideae)

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Plant Diversity 2021年第2期43卷 125-133页

作者： Luis Fernando Cuellar-Garrido Maria elena Siqueiros-Delgado Herbario Luz Maria Villarreal de Puga Del Instituto de Botanica(IBUG) Departamento de Botanica y ZoologíaCentro Universitario de Ciencias Biologicas y AgropecuariasUniversidad de GuadalajaraCamino Ing.Ramon Padilla Sanchez 2100CP 45200ZapopanJaliscoMexico Departamento de Biologia Centro de Ciencias BioasicasUniversidad Autonoma de AguascalientesAvenida Universidad 940CP 20131AguascalientesMexico

Two varieties of Bouteloua aristidoides have been recognized,the widespread *** and the more narrowly distributed *** two varieties differ in inflorescence form even more than that seen between many other closely related species of *** therefore asked whether these taxa might be better regarded as distinct species.A total of 93 vouchers were studied by using morphometry(principal components analysis and statistical tests),leaf micromorphology,ancestral state reconstruction,and/or molecular(ITS,trnC-rpoB and trnT-L-F)phylogenetic *** from the ITS tree,all results supported elevation of *** *** to the rank of species,thus the new combination Bouteloua arizonica(***)***&Columbus *** ***.,is *** and combined chloroplast-nuclear molecular trees depicted *** as monophyletic(even in sympatric populations with ***)and reveals phylogenetic structure within *** for which the presence of new undescribed varieties of ***(different from ***)is *** differs from *** in having fewer branches per inflorescence,a bigger branch with more spikelets,and a shorter branch *** electron microscopy revealed the presence of papillae on leaves of *** as a clear *** mature plants of *** from seeds in a greenhouse revealed a strong cleistogamous nature for this species for which gene flow in sympatric populations with *** seems unlikely.A taxonomic treatment and distribution map for identification of *** is provided.

关键词： Ancestral state reconstruction Bouteloua arizonica Cleistogamy Morphology Phylogeny Sympatry

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Metallographic Characterization of the Microstructure of Tool Steels

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材料热处理学报 2004年第5期25卷 169-173页

作者： George F Vander Voort elena P. Manilova BuehlerLtd. Lake Bluff Illinois USAPolzunov Central Boiler and Turbine Institute St. Petersburg Russia

Examination of selectively etched tool steel microstructures by light microscopy provides more information than standard etchants, such as nital, picral or Vilella’s reagent. Further, the images are more suitable for quantitative measurements, especially by image analysis. Specimens must be properly prepared, damage free, if selective etchants are to be applied successfully. A number of etchants have been claimed to selectively etch certain carbides in tool steels. The response of these etchants has been evaluated using a variety of well-characterized tool steel compositions. While many are selective, they are often selective to more than one type of carbide. Furthermore, their use in image analysis must be evaluated carefully as measurements showed that the amount and size of the carbides are often greater after selective etching as many of these reagents outline and color or attack the carbides. Selective etching of the matrix, leaving the carbides unaffected works well, but no one etchant will cover the broad spectrum of tool steel compositions. No etchant has been found that will color retained austenite in tool steels and image analysis of retained austenite in tool steels are always much lower than by x-ray diffraction unless retained austenite is the dominant phase present in grossly over-austenitized steels.

关键词：工具钢显微结构硬质合金腐蚀剂铁氧体图像分析马氏体残余奥氏体

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Warming induced changes in wood matter accumulation in tracheid walls of spruce

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Journal of Mountain Science 2020年第1期17卷 16-30页

作者： elena BABUSHKINA Dina ZHIRNOVA Liliana BELOKOPYTOVA Eugene VAGANOV Khakass Technical Institute Siberian Federal UniversityAbakan655017Russia Siberian Federal University Krasnoyarsk 660041Russia Sukachevlnstitute of Forest Siberian Branch of Russian Academy of SciencesKrasnoyarsk 660036Russia

The warming-driven increase of the vegetation season length impacts both net productivity and phenology of plants, changing an annual carbon cycle of terrestrial ecosystems. To evaluate this influence, tree growth along the temperature gradients can be investigated on various organization levels, beginning from detailed climatic records in xylem cells’ number and morphometric parameters. In this study, the Borus Ridge of the Western Sayan Mountains(South Siberia) was considered as a forest area under rapid climate change caused by massive Sayano-Shushenskoe reservoir. Several parameters of the xylem anatomical structure in Siberian spruce(Picea obovata Ledeb.)were derived from normalized tracheidograms of cell radial diameter and cell wall thickness and analyzed during 50 years across elevational gradient(at 520,960, and 1320 m a.s.l.). On the regional scale, the main warming by 0.42°C per decade occurs during cold period(November–March). Construction of the reservoir accelerated local warming substantially since 1980, when abrupt shift of the cold season temperature by 2.6°C occurred. It led to the vegetation season beginning 3-6 days earlier and ending 4-10 day later with more stable summer heat supply. Two spatial patterns were found in climatic response of maximal cell wall thickness:(1)temperature has maximal impact during 21-day period, and its seasonality shifts with elevation in tune with temperature gradient;(2) response to the date of temperature passing +9.5°C threshold is observed at two higher sites. Climate change yielded significantly bigger early wood spruce tracheids at all sites, but its impact on cell wall deposition process had elevational gradient: maximal wall thickness increased by 7.9% at the treeline, by 18.2% mid-range,and decreased by 4.9% at the lower boundary of spruce growth;normalized total cell wall area increased by 6.2%-6.8% at two higher sites but remained stable at the lowest one. We believe that these patterns are caused by two m

关键词： Climate change Sayano-Shushenskoe Reservoir Elevational gradient Picea obovata Quantitative wood anatomy Climate–growth relationship

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Chemical and rheological analysis of unaged and aged bio-extended binders containing lignin

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第6期10卷 947-963页

作者： elena Gaudenzi Fabrizio Cardone Xiaohu Lu Francesco Canestrari Department of Civil and Building Engineering and Architecture UniversitàPolitecnica delle MarcheAncona 60131Italy Nynas AB Nynäshamn 14982Sweden

The use of alternative renewable sources to totally or partially replace bitumen is one of the most current challenges in the road pavement *** growing energy cost and environmental concerns lead to the necessity to find alternative solutions,by supporting at the same time sustainability and circular economy *** this framework,this paper presents the application of a powder lignin,a natural bio-polymer deriving from byproducts of wood pulp and paper industry,to replace part of *** bituminous blend consisting in 70%of bitumen and 30%of powder lignin(by weight)was made in laboratory through the use of a high shear stirring mixer,and a reference plain bitumen characterized by a similar consistency(i.e.,same penetration grade)was used as ***,an extensive investigation on chemical and rheological properties of the bio-binder is *** transform infrared spectroscopy(FTIR),saturates,aromatics,resins and asphaltenes(SARA),bending beam rheometer(BBR),frequency sweep tests and multiple stress creep recovery tests(MSCR)with a dynamic shear rheometer(DSR)were ***,unaged,short-and long-term aging conditions were *** indicated that powder lignin dominates the rheological behavior of the bio-binder and,from chemical analysis,it seems that it partially acts as a filler and partially as a *** would result in improved performances at both low and high temperatures,leading to a wider temperature range of performance grade(PG).Moreover,despite a stiffening effect is recognized,lignin also offers an antioxidant potentiality,reducing the aging susceptibility of the investigated bio-binder.

关键词： Bio-binders Asphalt binders Lignin Aging Sustainability

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High tolerance to simulated root herbivory in hydroponically grown cuttings of Salix phylicifolia

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Journal of Forestry Research 2021年第6期32卷 2661-2668页

作者： Mikhail V.Kozlov elena L.Zvereva Department of Biology University of Turku20014TurkuFinland

The shortage of information regarding the effects of root damage on forest plants,especially trees and shrubs,is the most critical gap in our knowledge of belowground insect *** study examines how the tea-leaved willow,Salix phylicifolia,responds to simulated root herbivory and how nutrient availability affects these *** grown cuttings were used to precisely apply the desired levels of root ***:shoot ratios increased proportionally to the intensity of root damage,whereas specific leaf area,leaf water content and chlorophyll fluorescence were not *** removal of 2-64%of roots once in early summer and the removal of 25%of roots three times during the summer did not change biomass production by *** repeated removal of 50 and 75%of roots decreased shoot biomass and,to a lesser extent,total root *** tolerance of tea-leaved willow to root damage was greater in low nutrient treatment than in high nutrient treatment,thus supporting the Growth Rate *** to this model,in low resource conditions plants do not attain their maximum growth rate and therefore have a higher capacity for regrowth after *** conclude that,in the absence of water limitations,tea-leaved willow shows high tolerance to root losses and is unlikely to be affected by realistic levels of root herbivory.

关键词： Belowground herbivory Chlorophyll fluorescence Leaf water content Plant growth

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Comparison of pulse-modulated and continuous operation modes of a radio-frequency inductive ion source

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Plasma Science and Technology 2023年第2期25卷 131-145页

作者： Ilya ZADIRIEV elena KRALKINA Konstantin VAVILIN Alexander NIKONOV Georgy SHVIDKIY Physical Electronics Department Faculty of PhysicsLomonosov Moscow State UniversityMoscow 119991Russia

The paper describes an experimental study of the characteristics of a pulse-modulated radiofrequency(RF)discharge sustained at low pressures,typical of the operating modes of RF gridded ion *** motivation for the study is the question of whether the RF pulsemodulated mode can increase the efficiency of the ion *** ion current values extracted from an RF inductive ion source operating in continuous and pulse-modulated modes were *** experimental data were also compared with the parameter calculations based on a0D numerical model of the *** measurements showed that the pulse-modulated operation mode of the RF ion source had a noticeable advantage when the power of the RF generator was 140 W or ***,as the generator power increased,the advantage was lost because the pulse-modulated operation mode,having a higher RF power instant value,entered the region of existence sooner than the continuous mode,where the ion production cost begins to grow with RF power.

关键词： discharge plasma radio frequency(RF) pulse electrons ions

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Outpatient management of obscure gastrointestinal bleeding:A new perspective in high-risk patients

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World Journal of Gastroenterology 2024年第19期30卷 2502-2504页

作者： Maria elena Riccioni Clelia Marmo Digestive Endoscopy Unit Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy CEMAD Centro Malattie Dell’Apparato Digerente Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy

Mid-gastrointestinal bleeding accounts for approximately 5%-10%of all gastrointestinal bleeding cases,and vascular lesions represent the most frequent *** rebleeding rate for these lesions is quite high(about 42%).We hereby recommend that scheduled outpatient management of these patients could reduce the risk of rebleeding episodes.

关键词： Gastrointestinal bleeding Small bowel bleeding Recurrent bleeding Rebleeding risk Rebleeding Outpatient management

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Lynch syndrome and Lynch syndrome mimics: The growing complex landscape of hereditary colon cancer

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World Journal of Gastroenterology 2015年第31期21卷 9253-9261页

作者： John M Carethers elena M Stoffel Division of Gastroenterology Department of Internal MedicineUniversity of Michigan

Hereditary non-polyposis colorectal cancer(HNPCC) was previously synonymous with Lynch syndrome; however,identification of the role of germline mutations in the DNA mismatch repair(MMR) genes has made it possible to differentiate Lynch syndrome from other conditions associated with familial colorectal cancer(CRC). Broadly,HNPCC may be dichotomized into conditions that demonstrate defective DNA MMR and microsatellite instability(MSI) vs those conditions that demonstrate intact DNA MMR. Conditions characterized by MMR deficient CRCs include Lynch syndrome(germline MMR mutation),Lynch-like syndrome(biallelic somatic MMR mutations),constitutional MMR deficiency syndrome(biallelic germline MMR mutations),and sporadic MSI CRC(somatic biallelic methylation of MLH1). HNPCC conditions with intact DNA MMR associated with familial CRC include polymerase proofreading associated polyposis and familial colorectal cancer type X. Although next generation sequencing technologies have elucidated the genetic cause for some HNPCC conditions,others remain genetically undefined. Differentiating between Lynch syndrome and the other HNPCC disorders has profound implications for cancer risk assessment and surveillance of affected patients and their at-risk relatives. Clinical suspicion coupled with molecular tumor analysis and testing for germline mutations can help differentiate the clinical mimicry within HNPCC and facilitate diagnosis and management.

关键词： Hereditary non-polyposis colorectal cancer Lynch s

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