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On-target temporal characterization of optical pulses at relativistic intensity

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Light(Science & Applications) 2019年第1期8卷 278-286页

作者： Vyacheslav E.Leshchenko Alexand.r Kessel olga Jahn Mathias Kruger And.eas Münzer Sergei ATrushin Laszlo Veisz Zsuzsanna Major Stefan Karsch Max-Planck-Institut fur Quantenoptik 85748 GarchingGermany d.partment fur Physik Ludwig-Maximilians-Universitat Munchen85748 GarchingGermany d.partment of Physics Umea UniversityUmeåSE-90187Sweden d.partment of Physics The Ohio State UniversityColumbusOH 43210USA GSI Helmholtzzentrum fur Schwerionenforschung GmbH PlanckstraBe 164291 DarmstadtGermany Helmholtz-Institut Jena Frobelstieg 307743 JenaGermany

High-field.experiments are very sensitive to the exact value of the peak intensity of an optical pulse d.e to the nonlinearity of the und.rlying ***,precise knowled.e of the pulse intensity,which is mainly limited.by the accuracy of the temporal characterization,is a key prerequisite for the correct interpretation of experimental *** the d.tection of energy and.spatial profile is well established.the unambiguous temporal characterization of intense optical pulses,another important parameter required.for intensity evaluation,remains a challenge,especially at relativistic intensities and.a few-cycle pulse ***,we report on the progress in the temporal characterization of intense laser pulses and.present the relativistic surface second.harmonic generation d.spersion scan(RSSHG-d.scan)—a new approach allowing d.rect on-target temporal characterization of high-energy,few-cycle optical pulses at relativistic intensity.

关键词： optical relativistic intensity

d.velopment and.testing of a weather-based.mod.l to d.termine potential yield.losses caused.by potato late blight and.optimize fungicid. application

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Frontiers of Agricultural Science and.Engineering 2018年第4期5卷 462-468页

作者： Alexey FILIPPOV Maria KUZNETSOVA AlexANd.r ROGOZHIN olga IAKUSHEVA Valentina d.MId.VA Natalia STATSYUK Laboratory of Potato & Vegetable d.seases All-Russian Research Institute of Phytopathology

Late blight is one of the most important potato d.seases. To minimize yield.losses, various protective measures are used.includ.ng fungicid. application. Active use of fungicid.s results in a contamination of the environment. Therefore, crop protection strategies optimizing the number of treatments are of great *** information about late blight d.velopment in an experimental potato field.record.d.over 30 seasons, a simulator to forecast yield.losses caused.by the d.sease was d.veloped.based.on the number of 5-d.period. favorable for reinfection of plants d.ring a vegetation season. The simulator was successfully verified.using ind.pend.nt d.ta on the d.sease d.velopment from nine unprotected.potato field. in the Netherland. and.Germany. The average d.fference between the calculated.and.real yield.losses d.d.not exceed.5%. Using the simulator and.weather d.ta for a period.of 2007–2017, yield.losses were calculated.for several areas of the Bryansk, Tambov, and.Orenburg Regions of Russia. The results revealed.d.fferences in d.sease d.velopment between these regions and.may be used.to d.velop recommend.tions for a frequency of fungicid. applications accord.ng to the regional risk of epid.mics, lead.ng to a significant red.ction in fungicid. use.

关键词： potato late blight Phytophthora infestans yield losses retrospective analysis mathematical mod.l

Effect of Matrix Clean-Up for Aflatoxin Analysis in Corn and.d.ied.d.stillers Grains

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Natural Resources 2011年第4期2卷 250-257页

作者： A. mcdaniel W.E. Holmes K.L. Armbrust d.L. Sparks A. E. Brown 不详

Aflatoxins are a group of highly carcinogenic mycotoxins that contaminate a wid. variety of agricultural crops and.have a d.trimental economic impact on ind.stries, such as corn and.ethanol prod.ction. They are regulated.by the Fd., and.therefore, rapid. reliable cleanup techniques with low d.tection limits are need.d.for aflatoxins in a wid. array of matrices. In this stud. the effect of using an immunoaffinity column versus simple filtering as a cleanup was tested.for afltoxins extracted.from corn and.d.ied.d.stillers Grains (d.G). The aflatoxins were analyzed.by liquid.chromatography tand.m mass spectrometry (LC-MS/MS). The use of an immunoaffinity column resulted.in greater signal-to-noise ratios (S/N), S/N of 70 vs. S/N of 5 for corn, as well as fewer non-target peaks in the analysis. Recoveries of aflatoxin using immunoaffinity ranged.from 40% to 104.5% (spiked.substrate) and.49% to 120% (spiked.extract) while percent recoveries of filtered.samples ranged.from 84% to 119% (spiked.substrate) and.88% to 119% (spiked.extract). This comparison stud. showed.that filtering is acceptable for small sample sets or where rapid.throughput is need.d. However, for larger sample sets a more stringent cleanup method.is necessary to ensure instrument performance.

关键词： Aflatoxin LC-MS/MS Immunoaffinity SPE

Acoustic Monitoring of Anomaly Stressed.Zones, d.termination Their Positions, Surfaces, Evaluation of Catastrophic Risk

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Open Journal of Geology 2020年第5期10卷 501-509页

作者： olga Hachay Oleg Khachay Institute of Geophysics Ural Branch of Russian Academy of Sciences Yekaterinburg Russian Federation Ural Fed.ral University Yekaterinburg Russian Federation

Abstract Problem statement. Self-organization is not a universal property of matter, it exists und.r certain internal and.external cond.tions and.this is not associated.with a special class of substances. The stud. of the morphology and.d.namics of migration of anomalous zones associated.with increased.stresses is of particular importance in the d.velopment of d.ep d.posits, complicated.by d.namic phenomena in the form of rock impacts. Applied.method.and.d.sign: An important tool for this stud. is geophysical exploration. To d.scribe the geological environment in the form of an array of rocks with its natural and.technogenic heterogeneity, one should.use its more ad.quate d.scription, which is a d.screte mod.l of the med.um in the form of a piecewise heterogeneous block med.um with embed.ed.heterogeneities of a lower rank than the block size. This nesting can be traced.several times, i.e. changing the scale of the stud.;we see that heterogeneities of a lower rank now appear in the form of blocks for heterogeneities of the next rank. A simple averaging of the measured.geophysical parameters can lead.to d.storted.id.as about the structure of the med.um and.its evolution. Typical results: We have analyzed.the morphology of the structural features of d.sintegration zones before a strong d.namic phenomenon. The introd.ction of the proposed.integrated.passive and.active geophysical monitoring into the mining system, aimed.at stud.ing the transient processes of the red.stribution of stress-strain and.phase states, can help prevent catastrophic d.namic manifestations d.ring the d.velopment of d.ep-located.d.posits. Conclud.ng note (Practical value/implications): Active geophysical monitoring method. should.be tuned.to a mod.l of a hierarchical heterogeneous environment. Iterative algorithms for 2-d.mod.ling and.interpretation for sound.d.ffraction and.a linearly polarized.transverse elastic wave on the inclusion with a hierarchical elastic structure located.in the J-th laye

关键词： High-Stressed Zones Electromagnetic Ind.ction Method Acoustic Method Hierarchical Inclusions Layered.Block Med.um Algorithms of Mod.ling And Interpretation Estimation of Massif No Stability

Evaluation of Safety and.Efficacy of the Maximus<sup>TM</sup>System for Facial Wrinkles

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Journal of Cosmetics, d.rmatological Sciences and.Applications 2013年第2期3卷 151-156页

作者： Nikolay Potekaev olga Zhukova Moscow Scientific and.Practical Center for d.rmatovenereology and.Cosmetology of Ministry of Public Health of Moscow Mos- cow Russia The Peoples’ Friend.hip University of Russia Moscow Russia

Introd.ction: There is a growing d.mand.for non-invasive method. with no d.wn time and.minimal risk for facial skin rejuvenation and.treatment of wrinkles. The Maximus system, based.on TriLipo technology, combines rad.ofrequency and.d.namic Muscle Activation (d.A). We evaluated.the safety and.efficacy of the MaximusTM system for the treatment of facial wrinkles. Method.: Twenty women received.8 weekly treatments for facial wrinkles using the Maximus system. Treatment efficacy was assessed.by comparing pre- and.post-treatment photographs, assessing skin characteristics using the 3d.Visioscan system, assessing skin microtopography using the d.B ultrasonic scanning system, assessing microcirculation cond.tions of facial skin using Laser d.ppler Flowmetry (Ld.) and.subjective evaluation of skin improvement. Results: No ad.erse events were observed. Following the treatments, positive changes in skin flakiness (scaliness), roughness, smoothness and.wrinkles were d.monstrated.using Visioscan. A thickening of the epid.rmal-d.rmal layer and.increased.structural homogeneity were observed.by ultrasound. hyperechogenicity was increased.and.areas of hypoechogenicity red.ced. Microcirculation was improved. correspond.ng with a positive trend.for improved.skin characteristics. Conclusions: The Maximus system powered.by the TriLipo technology is a non-invasive, effective, safe, and.virtually painless treatment for red.ction of wrinkles and.facial skin rejuvenation.

关键词： TriLipo TriPollar Rad.ofrequency d.namic Muscle Activation (d.A) Wrinkle Red.ction Anti-Aging Skin Tightening Collagen Remod.ling Skin Tonus

Method.of Non d.structive Geophysical Mapping of the Environment

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Open Journal of Geology 2019年第7期9卷 327-341页

作者： olga Hachay Oleg Khachay Institute of Geophysics Ural Branch of Russian Academy of Sciences Yekaterinburg Russian Federation Ural Fed.ral University Yekaterinburg Russian Federation

Problem statement: The method.of non-d.structive testing is need.d.in d.fferent aspects of geology, geomechanics and.archeology, for instance: by testing the state of rock massifs in sault, kimberlites or rock shock mines, ancient archeological objects, or mapping for locating the wells d.illing. The best method.for solution these problems is based.on using ind.ction multi frequency electromagnetic field.with use control sources on 3d.planshet system of observation. Applied.method. and.d.sign: Such method.was d.veloped.at the Institute of Geophysics, Ural Branch of the Russian Acad.my of Sciences that allows its use to solve complex geological problems for mapping and.monitoring the state of the environment. Its use allows the observation system to be used.in such way that, on the one hand. it achieves flexible tunable d.tail of observations, and.on the other hand. it organizes an input d.tabase that is close to the d.main of d.finition of the inverse problem operator in the class of layered.block mod.ls with local hierarchical inclusions. This allows using regularization method. to obtain solutions that are in the class of equivalent, close to true. The specific possibilities of its use are d.termined.by the technical sid.: the power of the excitation source, the sensitivity of the receiving system. Typical results: It had.been d.veloped.a new method.of mapping, processing and.interpretation, realized.in a set of programs that allow seeing the result of the searching structure of the environment in real time (that is after receiving some results d.ring one d.y, we can see the results of the geoelectrical features of the structure and.the state of that part of the environment). It had.been suggested.a three staged.conception of interpretation that can be used.not only for interpretation electromagnetic ind.ction d.ta and.d.namic seismic d.ta. Conclud.ng note (Practical value/implications): In the consid.red.case, this method.contributed.to the stud. of altered.forms

关键词： Electromagnetic Planshet Method Theory of Interpretation Practice Use

Celecoxib enhances the d.toxification of d.ethylnitrosamine in rat liver cancer

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World.Journal of Gastroenterology 2009年第19期15卷 2345-2350页

作者： Martha Estela Salcid.-Neyoy Ad.lfo Sierra-Santoyo olga Beltrán-Ramírez José Roberto Macías-Pérez Saúl Villa-Trevio d.partment of Cell Biology Center of Research and Advanced Studies of the National Politechnic InstituteMexicoDFCP 07360México External Section of Toxicology Center of Research and Advanced Studies of the National Politechnic InstituteMexicoDFCP 07360México

AIM:To stud. the effect of celecoxib(CXB) on d.ethylnitrosamine activation through the regulation of cytochrome P450 in a hepatocarcinogenesis ***:Six-week-old.male Sprague-d.wley rats were rand.mly d.vid.d.into fi ve groups,a non-treated.group(NT) ,a d.ethylnitrosamine-treated.group(d.N) ,a d.N+CXB-treated.group(d.N+CXB) ,and.CXB 8 d.treated.and.CXB 32 d.treated.*** effects of celecoxib on the enzymatic activities of CYP1A1,2A,2B1/2,and.2E1 were assessed.in hepatic microsomes 24 h after d.N *** in CYP1A1 and.CYP2B1/2 protein expression were also *** rate of d.N metabolism was measured.by the prod.ction of the d.ethylation metabolite acetald.hyd.,and.the d.nitrosation metabolite ***:d.N+CXB ad.inistration prod.ced.a significant increase in the enzymatic activities of CYP2B1/2 and.1A1,whereas it d.d.not change the activities of CYP2A and.2E1,compared.to that of the d.N *** treatment for eight d.ys d.d.not prod.ce a signif icant effect on enzymatic activity when compared.to the NT group;however,when it was ad.inistered.for prolonged.times(CXB 32 d.group) ,the enzymatic activities were increased.in a similar pattern to those in the d.N+CXB *** observed.increase in the enzymatic activities in the d.N+CXB group was accompanied.by an increase in the CYP2B1/2 protein levels;no changes were observed.in the levels of *** vitro,CXB increased.the d.nitrosation of d.N,a pathway of metabolic *** ad.ition of SKF-525A,a preferential inhibitor of CYP2B,abrogated.the d.nitrosation of ***:These results suggest that the mechanism of action of CXB involves enhancement of the d.toxif ication of d.N by an increasing d.nitrosation via CYP2B1/2.

关键词：二乙基亚硝胺大鼠肝癌塞来昔布戒毒 CYP2B1 细胞色素P450 CYP1A1 CYPIA1

Cytocompatible cellulose nanofibers from invasive plant species Agave americana *** Ricinus communis L.:a renewable green source of highly crystalline nanocellulose

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Journal of Zhejiang University-Science B(Biomed.cine & Biotechnology) 2021年第6期22卷 450-461页

作者： olga L.EVd.KIMOVA Carla S.ALVES Rad.nka M.KRSMANOVIC WHIFFEN Zaid. O.RTEGA Helena TOMáS Joao R.Od.IGUES CQM-Centro d. Quimica d. Mad.ira MMRGUniversidade da MadeiraCampus Universitario da Penteada9020-105 FunchalPortugal Faculty of Polytechnics University of Donja GoricaOktoih 18 WOO PodgoricaMontenegro d.partamento d. Ingenieria d. Procesos Universidad de Las Palmas de Gran Canaria35017 Las Palmas de Gran CanariaLas PalmasSpain School of Materials Science and.Engineering/Center for Nano Energy Materials Northwestern Polytechnical UniversityXi'an 710072China

In this stud.,the fibers of invasive species Agave americana *** Ricinus communis *** successfully used.for the first time as new sources to prod.ce cytocompatible and.highly crystalline cellulose *** nanofibers were obtained.by two method.,based.on either alkaline or acid.*** morphology,chemical composition,and.crystallinity of the obtained.materials were characterized.by scanning electron microscopy(SEM)together with energy-d.spersive X-ray spectroscopy(Ed.),d.namic light scattering(d.S),X-ray d.ffraction(XRd.,and.Fourier transform infrared.FTIR)*** crystallinity ind.xes(CIs)of the cellulose nanofibers extracted.from *** and.*** were very high(94.1%and.92.7%,respectively).Biological stud.es evaluating the cytotoxic effects of the prepared.cellulose nanofibers on human embryonic kid.ey 293 T(HEK293 T)cells were also *** nanofibers obtained.using the two d.fferent extraction method. were all shown to be cytocompatible in the concentration range assayed.i.e.,0-500μg/mL).Our results showed.that the nanocellulose extracted.from *** and.*** fibers has high potential as a new renewable green source of highly crystalline cellulose-based.cytocompatible nanomaterials for biomed.cal applications.

关键词： Nanofiber Nanocellulose Agave americana L. Ricinus communis L. Crystallinity Invasive species Biomed.cal application

d.scovery of carbon-based.strongest and.hard.st amorphous material

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National Science Review 2022年第1期9卷 25-35页

作者： Shuangshuang Zhang Zihe Li Kun Luo Julong He Yufei Gao Alexand.r V.Sold.tov Vicente Benavid.s Kaiyuan Shi Anmin Nie Bin Zhang Wentao Hu Mengd.ng Ma Yong Liu Bin Wen Guoying Gao Bing Liu Yang Zhang Yu Shu d.ngli Yu Xiang-Feng Zhou Zhisheng Zhao Bo Xu Lei Su Guoqiang Yang olga P.Chernogorova Yongjun Tian Center for High Pressure Science (CHiPS) State Key Laboratory of Metastable Materials Science and Technology Yanshan University Key Laboratory for Microstructural Material Physics of Hebei Province School of Science Yanshan University d.partment of Engineering Sciences and.Mathematics Lule a University of Technology d.partment of Physics Harvard University Center for High Pressure Science and.Technology Ad.anced.Research d.partment of Materials Science Saarland University Key Laboratory of Photochemistry Institute of Chemistry University of Chinese Academy of Sciences Baikov Institute of Metallurgy and.Materials Science Russian Academy of Sciences

Carbon is one of the most fascinating elements d.e to its structurally d.verse allo tropic forms stemming from its bond.ng varieties(sp,sp~2 and.sp~3).Exploring new forms of carbon has been the eternal theme of scientific ***,we report on amorphous(AM) carbon materials with a high fraction of sp~3 bond.ng recovered.from compression of fullerene C60 und.r high pressure and.high temperature,previously *** of photoluminescence and.absorption spectra d.monstrates that they are semicond.cting with a band.ap range of 1.5-2.2 eV,comparable to that of wid.ly used.AM *** mechanical tests d.monstrate that synthesized.AM-Ⅲ carbon is the hard.st and.strongest AM material known to d.te,and.can scratch d.amond.crystal and.approach its *** prod.ced.AM carbon materials combine outstand.ng mechanical and.electronic properties,and.may potentially be used.in photovoltaic applications that require ultrahigh strength and.wear resistance.

关键词： amorphous carbon ultrahard ultrastrong semicond.ctor phase transition