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CLONING AND SEQUENCE ANALYSIS OF TWO SATELLITE RNAs FROM CUCUMBER MOSAIC VIRUS P1 ISOLATE

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CLONING AND SEQUENCE ANALYSIS OF TWO SATELLITE RNAs FROM CUC...

作者： Sandra perez Alvarez 浙江大学

学位级别：硕士

Cucumber mosaic virus （CMV） is a type member of the genus Cucumovirus. CMV have divided genomes consisting of three positive single-strands RNAs and a subgenomic RNA 4, which is generated by transcription from RNA 3 and serves as messenger RNA for the viral capsid protein. Some isolates of CMV contain abundant amounts of a small RNA （satellite RNA）, which is dependent on viral genomic RNA for its replication and spread, and has no appreciable nucleotide sequence similarity with the viral RNA. CMV can infect over 800 species of plants and is an economically important pathogen of field-grown vegetables in many areas of the world. In this study, the original cucumber mosaic virus （CMV） PI isolate has been caused very mild symptoms on many plant species, after serial passages of inoculation in 5 years, it was found that CMV P1 caused moderate symptoms on several tobacco cultivars and tomato. The dsRNA purification product were used for electrophoresis in agarose gel and the result show that the amount of satellite RNA is much higher than genomic RNAs and subgenomic RNA. Primers were synthesized based on reported CMV satellite RNA sequences, and a specific band of approximately 350 bases in length was found. In cloning and screening we found more than 20 white clones and only two were selected for sequence analysis. CMV PI sat-1 was 100% homology with a sequence reported in 1995, and the other one （CMV PI sat-2） was a new satellite. CMV P1 sat-1 is a mild satellite with about 335nt and CMV PI sat-2 is a new satellite （necrotic satellite） with 394nt, it is not a mutation from CMV P1 sat-1 because there are several deletions. The two satellites shared about 90% sequence homology. The two sequenced satellite RNAs have at least one open reading frame （ORF）. CMV P1 sat-1 share an ORF starting at nucleotide 11 and terminating at nucleotide 169. CMV P1 sat-2 has an ORF starting at residue 369 and terminating at residue 394, a second one s

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Mapping of groundwater potential zones in the drought-prone areas of south Madagascar using geospatial techniques

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Geoscience Frontiers 2020年第4期11卷 1403-1413页

作者： Charles Serele Ana perez-Hoyos Francois Kayitakire UNICEF Madagascar European Commission Joint Research Centre(JRC)Via E.Fermi 2749I-21027IspraVAItaly

The southern regions of Madagascar have the country’s lowest water supply coverage and are highly vulnerable to *** to potable drinking water is a major challenge for the local *** droughts lead to annual emergency appeals to save the lives of acute malnourished ***’s response consisting in providing potable drinking water through the drilling of boreholes has been challenged by the complex hydrogeology,the low yield of boreholes and high-level salinity of water,the lack of reliable groundwater data and the weak capacity of the drilling *** constraints result in a high rate of drilling *** improve drilling success and provide more potable drinking water to local communities,it is vital to undertake reliable groundwater *** Madagascar and the European Union delegation in Madagascar collaborated on the use of satellite imagery to improve sector knowledge and access to safe and clean water for local communities in southern *** methodology relies on produce thematic layers of groundwater potential ***,these thematic layers were overlaid with ground-based hydrogeological data to map the groundwater potential zones(GWP) and identify the most suitable sites for borehole siting and *** of this study are very encouraging,and the integrated approach used has proven its applicability in mapping groundwater potential areas in the eight drought-affected areas of south *** groundwater potential zone map is being used by UNICEF and partners to plan water supply projects and identify the best sites for positioning new boreholes and reduce the likelihood of drilling ***,the project developed a database of groundwater resources,which will improve knowledge of the regional hydrogeological context and strengthen the capacity of the water *** learnt from this study show that an integration of the groundwater potential zone map with demographics a

关键词： Groundwater potential zones(GWP) Overlay analysis Remote sensing Geographic information system(GIS) South Madagascar

Zeta potential measurement on lithium lanthanum titanate nanoceramics

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Particuology 2016年第1期14卷 69-72页

作者： Carlos Ricardo Milian Pila Eduardo perez Cappe Yodalgis Mosqueda Laffita Oswaldo Luiz Alves Institute of Materials Science and Technology (IMRE) Havana University Havana CP 10400 Cuba Solid state Chemistry Laboratory Institute of Chemistry Campinas University Campinas CP 13083-970 SP Brazil

The zeta potential, isoelectric point, and agglomeration of ***3 （LLTO） nanoparticles dispersed in aqueous media at different ionic strengths have been studied. The zeta potential was determined from electrophoretic mobility measurements, according to Smoluchowski＇s equation, for Li0.5La0.5TiO3 suspen- sions in NaCl and KCI electrolytes with ionic strengths of 1, 10, and 100 mmol/dm3. The isoelectric point （IEP）, zeta potential （ζ）, and the agglomeration were shown to strongly depend on the ionic strength of the Li0.5La0.5TiO3 aqueous colloidal suspension in both NaCI and KCI electrolytes, which allows the deter- mination of the effects of environmental conditions for ***3 manipulation in aqueous colloidal systems. The suspensions of Li0.5La0.5TiO3 nanoparticles reach the IEP in the pH range 0f3-5. The （ of Li0.5La0.5TiO3 nanoparticles varied from positive to negative values with a pH increase, which allows for the control of the surface charge depending on the purpose. The pH range of 7-g and an ionic strength ≤1 mmol/dm3 are recommended as the most suitable conditions for both the LLTO colloidal shaping techniques application and the LLTO-based nanocomposite formation.

关键词： Titanate Nanoparticles Zeta potential Colloidal suspension

Efficient removal of the recalcitrant metamizole contaminant from drinking water by using a CaLaCoO_(9) perovskite supported on recycled polyethylene

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Journal of Environmental Sciences 2024年第2期136卷 56-67页

作者： Ernesto Valadez-Renteria Christian perez-Carrasco Dulce Yolotzin Medina-Velazquez Vicente Rodriguez-Gonzalez Jorge Oliva CONACYT-División de Materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A.C.San Luis PotosíSLP 78216México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana AzcapotzalcoCol.Reynosa-TamaulipasC.P.MéxicoDF 02200México

Metamizole(MZ)is a widely used anti-inflammatory *** to its common use,this contaminant is found in sewage and *** order to reduce the contamination produced by the MZ,we fabricated in this work a photocatalytic composite using recycled polyethylene(RPE)and the CaLaCoO_(9)(LCCO)*** nanoparticles had a microplate-like morphology and sizes of 1.4–5.5μm according to the analysis of *** photocatalytic properties of the LCCO powders were evaluated under ultraviolet-visible(UV-Vis)irradiation and found a removal efficiency of 96%.When the RPE+LCCO composite was employed for the photocatalytic degradation of MZ,a maximum degradation of 92.5%was *** influence of the pH on the photocatalytic activity was also studied and found that an initial pH=3 produced a total degradation of MZ after 240 min of UV-Vis ***,three reuse cycles were carried out for the pure LCCO powders and for the RPE+LCCO composites and found that the maximum loss of degradation was 5%.Furthermore,scavenger experiments demonstrated that the super oxide and hydroxyl radicals are formed during the photocatalytic reaction and were responsible for the degradation of ***,the X-ray photoelectron-spectroscopy and Raman analysis demonstrated the formation of defects(oxygen vacancies),those ones delayed the electron-hole recombination,which in turn,enhanced the degradation of the ***,the studies performed in this work proved that composites made with recycled plastics and LCCO perovskites are a low-cost and feasible alternative for the cleaning of water sources polluted with pharmaceutical compounds.

关键词： Photocatalysis Metamizole Pharmaceutical contaminant UV-Vis irradiation Perovskite

How linear molecules resist to shear:the origin of nanoscale friction

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Science China(Physics,Mechanics & Astronomy) 2004年第Z1期47卷 15-20页

作者： Linmao QIAN G.Luengo E.perez Laboratoire de Physique Statistique de I’Ecole Normale Superieure associee au CNRS et aux Univer-sites Paris Vl et Paris Vll24rue Lhomond75231 Paris Cedex 05France Key Laboratory of Advanced Technologies of Materials(Ministry of Education) Tribology Research InstituteSouthwest Jiaotong UniversityChengdu 610031China

Friction force measurements between smooth surfaces across two layers of linear alkanes over five decades of speeds are presented. A maximum friction dissipation is observed at a characteristic speed. The behaviour is described by a new approach: the formation and destruction of molecular bridges between confined alkane layers. The bridges interdigitated between the layers exhibit a thermally activated resistance to *** analytical model involving activation barriers accounts for the overall behaviour of the forces over four decades of speed. This first simple semi-quantitative description sheds new light on the subtle mechanisms of friction at the nanoscale level and shows how the molecular length influences the tribological properties of the liquid.

关键词： nanotribology, friction, surface force apparatus, interface molecular films, linear alkanes.

Synthesis of phosphonated graphene oxide by electrochemical exfoliation to enhance the performance and durability of high-temperature proton exchange membrane fuel cells

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Journal of Energy Chemistry 2023年第1期76卷 448-458,I0011页

作者： Jianuo Chen Zunmin Guo Maria perez-Page Yifeng Jia Ziyu Zhao Stuart M.Holmes Department of Chemical Engineering and Analytical Science University of ManchesterOxford RoadManchester M139PLUnited Kingdom Chemistry Research Laboratory Department of ChemistryUniversity of Oxford12 Mansfield RoadOxford OX13TAUnited Kingdom

The doping of functionalized graphene oxide(GO)in the membranes becomes a promising method for improving the performance of high-temperature proton exchange membrane fuel cells(HT-PEMFC).Phosphonated graphene oxide(PGO)with a P/O ratio of 8.5%was quickly synthesised by one-step electrochemical exfoliation based on a three-dimensiaonal(3D)printed reactor and natural graphite *** with the GO prepared by the two-step electrochemical exfoliation method,the PGO synthesized by the one-step electrochemical exfoliation can better improve the performance of the membrane-electrode-assembly(MEA)based on the polybenzimidazole(PBI)membrane in the *** doping of 1.5 wt%GO synthesised by electrochemical exfoliation with the 2-step method or reactor method in PBI increased the peak power density by 17.4%or 35.4%compared to MEA based on pure PBI membrane at 150℃,*** addition,the doping of PGO in PBI improves its durability under accelerated stress test(AST).

关键词： Electrochemical exfoliation Phosphonated graphene oxide High-temperature fuel cells

二十世纪六十年代以来哥伦比亚和美国的女权主义对比研究

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二十世纪六十年代以来哥伦比亚和美国的女权主义对比研究

作者： Melissa Suarez amaya 厦门大学

学位级别：硕士

本文以国际关系为视角,将女权主义纳入国际关系理论之中进行研究。文献研究分为三部分,包括女权主义理论、女权主义发展历史以及研究方法。其中女权主义发展历史以及研究方法两部分主要对比研究了美国和哥伦比亚两国的女权主义发展进程... 详细信息

本文以国际关系为视角,将女权主义纳入国际关系理论之中进行研究。文献研究分为三部分,包括女权主义理论、女权主义发展历史以及研究方法。其中女权主义发展历史以及研究方法两部分主要对比研究了美国和哥伦比亚两国的女权主义发展进程。论文重点研究了美国和哥伦比亚两国的女性主义艺术,以此突出本文主题。论文发现以女性为主题的艺术创作见证了女权主义发展,也能帮助人们更好地研究女性运动的演变和调整。这一部分研究以史实为背景进行。本文研究结论会记录女权主义的构建过程,同时也可能阐释某些社会问题(涉及政治、历史以及文化等)和妇女问题之间的相互影响关系。

关键词：国际关系女权主义女性女性主义艺术哥伦比亚美国

Metabolomics-assisted refinement of the pathways of steroidal glycoalkaloid biosynthesis in the tomato clade

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Journal of Integrative Plant Biology 2014年第9期56卷 864-875页

作者： Kevin Schwahn Leonardo perez de Souza Alisdair R.Fernie Takayuki Tohge University of Potsdam AG BioinformaticsInstitute for Biochemistry and Biology MaxPlanck-Institute of Molecular Plant Physiology

Steroidal glycoalkaloids（SGAs） are nitrogen-containing secondary metabolites of the Solanum species,which are known to have large chemical and bioactive diversity in *** recent effort and development on LC/MS techniques for SGA profiling have elucidated the main pathways of SGA metabolism in tomato,the problem of peak annotation still remains due to the vast diversity of chemical structure and similar on overlapping of chemical *** we provide a case study of peak classification and annotation approach by integration of species and tissue specificities of SGA accumulation for provision of comprehensive pathways of SGA *** order to elucidate natural diversity of SGA biosynthesis,a total of 169 putative SGAs found in eight tomato accessions（Soianum lycopersicum, ***, ***, ***, ***,***,***,***） and four tissue types were used for correlation *** results obtained in this study contribute annotation and classification of SGAs as well as detecting putative novel biosynthetic branch *** such this represents a novel strategy for peak annotation for plant secondary metabolites.

关键词： Fruit ripening glycoalkaloids secondary metabolite Solanum lycopersicum tomato accessions

Effect of music on patients undergoing outpatient colonoscopy

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World Journal of Gastroenterology 2006年第45期12卷 7309-7312页

作者： Matthew L Bechtold Rodney A perez Srinivas R Puli John B Marshall Division of Gastroenterology University of Missouri School of Medicine Columbia Missouri United States

AIM: To evaluate the effect of relaxing music during colonoscopy under low-dose conscious sedation, on patient satisfaction, scope insertion time and procedure duration, medication doses, and the perceived adequacy of sedation and scope insertion difficulty on the part of the endoscopist. METHODS: One hundred and sixty-seven consecutive adult outpatients presenting for routine colonoscopy under low-dose conscious sedation were randomized to undergo their procedures either with music played during the procedure or no music played. RESULTS: There were no statistical differences between the two groups in terms of meperidine dose, midazolam dose, time to reach the cecum, total procedure time, endoscopist assessment of scope insertion difficulty, endoscopist assessment of adequacy of sedation, or the pain experience of the patients during their procedure. The music group did report significantly better overall procedure satisfaction as compared to the non music group on two of our three different scales. CONCLUSION: While music does not result in shortened procedure times, lower doses of sedative medications or perceived patient pain, the patients who have music playing during their procedures report modestly greater satisfaction with their procedures.

关键词： Colonoscopy Gastrointestinal endoscopy Music Music therapy Relaxation music