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Surfactant-free synthesis of metallic bismuth spheres by microwave-assisted solvothermal approach as a function of the power level

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Frontiers of Materials Science 2016年第4期10卷 394-404页

作者： Miriam ESTRADA FLORES Patricia SANTIAGO JACINTO Carmen M. REZA SAN GERMAN Luis RENDON VAZQUEZ Raul BORJA URBY nicolas cayetano castro Instituto de Investigaciones en Materiales Circuito Exterior S/N Zona de Institutos Ciudad Universitaria C.P. 04510 Mexico D.F. Mexico Instituto de Fisica Circuito de la Investigaci6n Cientffica Edificio Marcos MoshinskyLaboratorio de Materiales Nanoestructurados Ciudad Universitaria C.P. 04510 Mexico D.F. Mexico Escuela Superior de Ingenierfa Qufmica e Industrias Extractivas Unidad Profesional Adolfo L6pez Mateos Edif. Z-5 2do. Piso Instituto Politecnico Nacional C.P. 07738 Mexico D.F. Mexico Centro de Nanociencias y Micro y Nanotecnologfas. Instituto Politecnico Nacional Av. Luis Enrique Erro S/NUnidad Profesional Adolfo Lopez Mateos Zacatenco Delegaci6n Gustavo A. Madero C.P. 07738 Mexico D.F. Mexico

In the present work, the synthesis of micro- and nano-sized spheres of metallic bismuth by microwave-assisted solvothermal method is reported. The synthesis method was carried out at different power levels and at a unique frequency of microwave irradiation. The sphere sizes were controlled by the microwave power level and the concentration of dissolved precursor. Structural and morphological characterization was performed by SEM, HRTEM, EELS and XRD. The results demonstrated that rhombohedral zero valent Bi spheres were synthesized after microwave radiation at 600 and 1200 W. However, if the power level is decreased to 120 W, a monoclinic phase of Bi203 is obtained with a flake-like morphology. In comparison with a conventional hydrothermal process, the microwave-assisted solvothermal approach provides many advantages such as shorter reaction time, optimum manipulation of morphologies and provides a specific chemical phase and avoids the mixture of structural phases and morphologies which is essential for further applications such as drug delivery or functionalization with organic materials, thanks to its biocompatibility.

关键词： microwave oven power level metallic bismuth spherical structures mechanism of formation electron energy loss spectroscopy (EELS)

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Influence of Seven Growth Regulators on Fruit Set, Pollen Germination and Pollen Tube Growth of Almonds

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Journal of Agricultural Science and Technology(B) 2012年第9期2卷 1051-1056页

作者： Carlos Sotomayor Jorge castro nicolas Velasco Roman Toro Pontificia Universidad Catolica de Chile Faculty of Agronomy and Forestry Engineering Santiago Chile

To improve fruit set in ＂Carmel＂ almond （Prunus dulcis） trees grown in the 6th region of Chile, seven different growth regulators （GRs） were sprayed onto flowering branches： gibberellic acid （GA3）, Promalin, naphthaleneacetic acid （NAA）, Thidiazuron, Kinetin, Point-tomatomone and Brassinolide. The percentage of fruit set was determined by comparing the initial number of flowers present on each treated branch with the total number of almonds on the branches 50 days after anthesis. In comparison to the controls, Brassinolide, Point-tomatomone and Promalin achieved increases in fruit set of 19.4%, 14.5% and 12.9%, respectively. A parallel experiment was done in vitro, on the effects of these GRs on pollen germination and pollen tube growth. The greatest pollen germination （4 hours at 20 ~C） occurred with Brassinolide and GA3, which were significantly higher than the control, while NAA and Promalin significantly reduced germination. For pollen tube growth （24 hours at 20 ~C）, the greatest lengths were observed with Point-tomatomone and Brassinolide, which were significantly longer than the control, while NAA, Thidiazuron and Promalin were significantly shorter than the control, and the least growth was observed with Kinetin.

关键词： Almond growth regulators pollination fruit set.

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Synthesis and Characterization of GaN Rods Prepared by Ammono-Chemical Vapor Deposition

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Advances in Chemical Engineering and Science 2012年第2期2卷 292-299页

作者： Gregorio Guadalupe Carbajal Arízaga Karina Viridiana Chávez Hernández Nicolás cayetano castro Manuel Herrera Zaldivar Rafael García Gutiérrez Oscar Edel Contreras López Centro de Investigación en Física Universidad de Sonora Hermosillo México Centro de Nanociencias y Nanotecnología Universidad Nacional Autónoma de México Ensenada México Departamento de Química Universidad de Guadalajara Guadalajara México Instituto Potosino de Investigación Científica y Tecnológica (IPICYT) División de Materiales Avanzados (LINAN) San Luis Potosí México

GaN rods were deposited by chemical vapor deposition (CVD) onto sapphire (0 0 0 1) and amorphous quartz. The reactive Ga species in vapor the phase was formed with NH4Cl and gallium. The unidirectional growth was catalyzed with gold nanoparticles formed onto the substrate prior to the CVD reaction in order to induce a vapor-liquid-solid (VLS) mechanism. However, this method of synthesis seems to be influenced by other growth mechanisms which formed additional depositions of GaN with different morphology than the rods catalyzed by gold nanoparticles. The moieties of GaN that grew in the absence of gold formed branches in the rods or increased the lateral growth of rods resulting in larger diameters than the size of the gold particle that guided the growth.

关键词： Crystal Morphology Nanostructures Chemical Vapor Deposition Processes Semiconducting III-V Material

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Impact of 1,7-malaria reactive community-based testing and response(1,7-mRCTR)approach on malaria prevalence inTanzania

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Infectious Diseases of Poverty 2023年第6期12卷 103-104页

作者： Wei Chang Jessica Cohen Duo‑Quan Wang Salim Abdulla Muhidin Kassim Mahende Tegemeo Gavana Valerie Scott Hajirani M.Msuya Mary Mwanyika‑Sando Ritha John ANjau Shen‑Ning Lu Silas Temu Honorati Masanja Wilbald Anthony Maru Aregawi W Naveen Sunder Tang Kun Katia Bruxvoort Jovin Kitau Fadhila Kihwele Godlove Chila Mihayo Michael Marcia castro nicolas AMenzies Sein Kim Xiao Ning Xiao‑Nong Zhou Prosper Chaki Yeromin P.Mlacha Department of Global Health and Population Harvard T.H. Chan School of Public Health Boston USA Chinese Center for Disease Control and Prevention National Institute of Parasitic Diseases Shanghai People’s Republic of China School of Global Health Chinese Center for Tropical Diseases Research Shanghai Jiao Tong University School of Medicine Shanghai People’s Republic of China Chinese Center for Tropical Diseases Research Shanghai People’s Republic of China WHO Collaborating Centre for Tropical Diseases Shanghai People’s Republic of China Ifakara Health Institute Dar es Salaam United Republic of Tanzania Africa Academy for Public Health Dar es Salaam Tanzania Muhimbili University of Health and Allied Sciences Dar es Salaam Tanzania National Center for International Research on Tropical Diseases Ministry of Science and Technology Shanghai People’s Republic of China Global Malaria Programme World Health Organization Geneva Switzerland Bentley University Waltham USA Vanke School of Public Health Tsinghua University Beijing People’s Republic of China School of Public Health University of Alabama at Birmingham Birmingham USA The Pan-African Mosquito Control Association (PAMCA) KEMRI Headquarters Nairobi Kenya

Background Progress in malaria control has stalled in recent years and innovative surveillance and response approaches are needed to accelerate malaria control and elimination eforts in endemic areas of ***‑ing on a previous China-UK-Tanzania pilot study on malaria control,this study aimed to assess the impact of the 1,7-malaria Reactive Community-Based Testing and Response(1,7-mRCTR)approach implemented over two years in three districts of *** The 1,7-mRCTR approach provides community-based malaria testing via rapid diagnostic tests and treat‑ment in villages with the highest burden of malaria incidence based on surveillance data from health *** used a diference-in-diferences quasi-experimental design with linear probability models and two waves of crosssectional household surveys to assess the impact of 1,7-mRCTR on malaria *** conducted sensitivity analyses to assess the robustness of our results,examined how intervention efects varied in subgroups,and explored alternative explanations for the observed *** Between October 2019 and September 2021,244,771 community-based malaria rapid tests were com‑pleted in intervention areas,and each intervention village received an average of 3.85 rounds of *** prevalence declined from 27.4%at baseline to 11.7%at endline in the intervention areas and from 26.0%to 16.0%in the control areas.1,7-mRCTR was associated with a 4.5-percentage-point decrease in malaria prevalence(95%confdence interval:−0.067,−0.023),equivalent to a 17%reduction from the *** Rufji,a district characterized by lower prevalence and where larviciding was additionally provided,1,7-mRCTR was associated with a 63.9%decline in malaria *** The 1,7-mRCTR approach reduced malaria *** implementation interruptions due to the COVID-19 pandemic and supply chain challenges,the study provided novel evidence on the efectiveness of community-based reactive approache

关键词： Malaria Surveillance and response Incidence rate Community-health worker Health facility Communitybased testing and treatment 1,7-mRCTR Tanzania

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Comparison of Apigenin,Quercetin and Kaempferol Accumulation and Total Flavonoid Content in Leaves,Embryogenic Cultures and Cell Suspension Cultures of Parsley(Petroselinum crispum)

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Phyton-International Journal of Experimental Botany 2023年第10期92卷 2807-2823页

作者： Laura Isabel Arias-Rodríguez Martha Alicia Rodríguez-Mendiola Carlos Arias-castro Federico Antonio Gutiérrez Miceli Diana Reséndez Pérez María Celina Luján Hidalgo Juan JoséVillalobos Maldonado Norma Alejandra Mancilla Margalli Analytical Laboratory National Technological Institute of MexicoTuxtla Gutierrez CampusTuxtla GutierrezMexico Plant Biotechnology Laboratory Instrumental Analysis LaboratoryPlant Biochemistry LaboratoryNational Technological Institute of MexicoTlajomulco de ZunigaMexico Department of Cellular Biology and Genetics Faculty of Biological SciencesAutonomous University of Nuevo LeonSan Nicolas delos GarzaMexico

In recent years,there has been a growing interest in exploring alternative treatments for bone *** tissue engineering has turned its attention to plant extracts containing osteogenic flavonoids as potential promoters of bone *** our study,we specifically investigated the extract of Petroselinum crispum,a plant known for its abundance of osteogenic flavonoids such as apigenin,quercetin,and *** objective was to compare the total flavonoid content(TFC)and their accumulation in different *** obtained hydrolyzed aqueous extracts from the leaves of parsley plants(grown for 12 weeks in the field),weekly embryogenic cultures,and suspension cell *** TFC,measured in mg quercetin equivalent per gram of dry weight(QE mg/g dw),was found to be 53.81±0.97 for 52 g dw of leaves(1 kg plant fw),31.10±1.52 for 420 g dw of embryogenic cultures,and 11.80±0.76 for 210 g dw of cell ***,only the leaves and embryogenic cultures showed significant accumulation of osteogenic flavonoids,with apigenin levels of 1.8±0.3 and 0.32±0.02 mg/g dw,and kaempferol levels of 1.0±0.18 and 0.2±0.01 mg/g dw,*** findings indicate that embryogenic cultures have the potential to produce up to 40%more apigenin in 12 weeks compared to 1 kg of parsley plant,thanks to their superior biomass reproductive *** results present a promising biotechnological approach for generating extracts enriched with bioactive compounds,which can be further utilized in in vitro osteogenic testing.

关键词： Parsley(Petroselinum crispum)cultures osteogenic flavonoids bone regeneration aqueous extracts

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Detection of dengue virus serotype 3 in Cajamarca,Peru:Molecular diagnosis and clinical characteristics

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Asian Pacific Journal of Tropical Medicine 2021年第10期14卷 456-462页

作者： Miguel Angel Aguilar-Luis Hugo Carrillo-Ng Sungmin Kym Wilmer Silva-Caso Eduardo Verne Luis J.del Valle Jorge Bazán-Mayra Victor Zavaleta-Gavidia Daniel Cornejo-Pacherres Yordi Tarazona-castro Ronald Aquino-Ortega Angela Cornejo-Tapia Juana del Valle-Mendoza School of Medicine Research and Innovation Center of the Faculty of Health SciencesUniversidad Peruana de Ciencias AplicadasLimaPeru Laboratorio de Biologia Molecular Instituto de Investigación NutricionalLimaPeru Facultad de Medicina Alberto Hurtado Universidad Peruana Cayetano HerediaLimaPeru Division of Infectious Diseases Department of Internal MedicineChungnam National University School of MedicineDaejeonRepublic of Korea Barcelona Research Center for Multiscale Science and Engineering Departament d'Enginyeria QuímicaEEBEUniversitat Politècnica de Catalunya(UPC)BarcelonaSpain Laboratorio Regional de Cajamarca Dirección Regional de Salud de Cajamarca(DIRESA)CajamarcaPeru

Objective:To describe and molecularly characterize an outbreak of dengue virus(DENV)infection in Cajamarca,an Andean region in ***:A total of 359 serum samples from patients with acute febrile illness were assessed for the presence of DENV via RT-PCR,ELISA NS1,Ig M and Ig G in Cajamarca,Peru from January 2017 to June *** evaluation of the different diagnostic tests and their applicability was ***:Dengue virus was detected in 24.7%of samples by ***,serological analysis detected 30.3%positive cases via ELISA NS1 antigen,16.7%via ELISA Ig G and 9.7%via ELISA Ig *** of the cases corresponded to DENV-3(77.5%).The use of RT-PCR performed better in primary infections(P<0.01),while detection of ELISA Ig M performed better in secondary infections(P<0.01).The combination of NS1 and Ig M performed better than the other assays in detecting primary(92.5%)and secondary infections(96.6%).The most frequent symptoms associated with fever were headaches,myalgias,and arthralgias across all ***:We report an important outbreak of dengue infection caused by DENV-3 in Cajamarca,*** findings encourage the use of NS1 antigen and Ig M *** findings demonstrate an increasing expansion of DENV-3 in Peru and highlight the importance of molecular diagnosis and serotype characterization among the clinically defined dengue cases to strengthen the Peruvian epidemiological surveillance.

关键词： Dengue DENV Arbovirus Diagnosis Peru

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