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Genetic variability of Rhizoctonia solani Kühn and its resistance to fungicides

Studies in Fungi 2020年第1期5卷 381-391页

作者： Castillo RF Gallegos G flores OA Aguilar GC Rodriguez HR Hernandez CFD Saltillo Experimental Station Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias.Carr.Saltillo-Zacatecas km 342+119No.9515Col.ExHacienda de BuenavistaSaltilloCoah.C.P.25315 Department of Agricultural Parasitology Universidad Autónoma Agraria Antonio NarroBuenavista25315SaltilloCoahuilaMéxico Food Research Department School of Chemical SciencesUniversidad Autónoma de Coahuila25000SaltilloCoahuilaMexico

The aims of this study are to determine the population genetic structure of Rhizoctonia solani,associated with potato,and to assess its resistance degree to pencycuron and thiabendazole fungicides.A total of 57 strains of R.Solani were isolated from different potato crop fields in mexico,and were classified according to their anastomosis group(AG)using the polymerase chain reaction(PCR)and restriction fragment length polymorphism(RFLP)-based analysis.Then,the amplified fragments were digested with four different endonucleases(mse I,Ava II,mun I and Hinc II).The Repetitive Element Sequence-Based PCR(rep-PCR)technique was used to determine the genetic diversity in R.solani populations.Results obtained by PCR-RFLP showed that 81%of the isolates were identified as belonging to AG-3 group,14%to AG1-1B and 5%to AG-11 group.In response to fungicides inhibition,IC_(50)between 0.014-0.039 mg a.i./L for pencycuron,and 0.82 to 2.91 for thiabendazole were determined,This IC_(50)value showed that the resistance factor(RF)values ranged from 1.4 to 3.945 and 0.27 to 0.97,respectively;this tendency suggests that isolates are susceptible to thiabendazole.The AG groups showed a heterogeneous resistance to pencycuron and thiabendazole,being more tolerant to these fungicides AG1-1B and AG-11 groups.The genetic analysis shows a low genetic diversity among(P-value 0.3225)and within(P-value 0.3275)populations;this can indicate a clonal reproduction and little parasexual cycle among the analyzed isolations.

关键词： Anastomosis group genetic diversity genetic resistance mexico PCR RFLP parasexual cycle REP PCR Wright’s statistics

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Near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： Alejandro Rodríguez-Castellanos manuel Carbajal-Romero Norberto flores-Guzmán J.Efraín Rodríguez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary Element method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

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复合硫化物浮选作业循环水中钙和硫酸根离子去除的热力学及实验研究

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Transactions of Nonferrous metals Society of China 2021年第10期31卷 3116-3127页

作者： Elvis BUSTOS-flores martha Araceli ELIZONDO-ÁLVAREZ Alejandro URIBE-SALAS Department of metallurgical Engineering CINVESTAV-IPNUnidad Saltillo25900Ramos ArizpeCoahuilaMexico

研究一种用氯化钡(BaCl_(2)∙2H_(2)O)和磷酸钠(Na_(3)PO_(4))去除饱和溶液中(0.016 mol/L CaSO_(4))硫酸钙的化学方法。主要目的是通过沉淀出两种固体物质从溶液中去除这些离子:硫酸根(SO_(4)^(2−))沉淀为重晶石(BaSO_(4)),钙(Ca^(2+))沉淀为羟基磷灰石(Ca_(5)(PO_(4))_(3)OH)。此外,探索一种用油酸和十二烷基胺作捕集剂的固体/液体分离方法(即浮选)。结果表明,在60℃、pH 11.5下用3.9 g/L BaCl_(2)·2H_(2)O和1.6 g/L Na_(3)PO_(4)对饱和溶液进行化学处理,促进硫酸钡和缺钙羟基磷灰石(Ca_(10−x)(HPO_(4))_(x)(PO_(4))_(6−x)(OH)_(2−x))的沉淀,钙和硫酸根的残余浓度分别低于0.10和5 mg/L。当反应剂用量相同、在低于上述温度和pH值下处理时,残余钙浓度增加到28 mg/L。用油酸作捕集剂、pH 9.5时羟基磷灰石的浮选回收率最高,约为80%;而用十二烷基胺作捕集剂、pH 6.5时重晶石的浮选回收率约为90%。

关键词：钙硫酸盐十二烷基胺油酸重晶石羟基磷灰石浮选分离

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基于无人机图像以及不同机器学习和深度学习模型的小麦倒伏率检测

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智慧农业（中英文） 2021年第2期3卷 23-34页

作者： Paulo flores 张昭北达科他州州立大学农业与生物系统工程系美国北达科他州法戈市58102

小麦在生长过程中发生倒伏会严重影响其产量,因此实时且准确地对小麦倒伏状况监测有很重要的意义。传统的方法采用手工方式生成数据集,不仅效率低、易出错,而且生成的数据集不准确。针对这一问题,本研究提出了一种基于图像处理的自动数... 详细信息

小麦在生长过程中发生倒伏会严重影响其产量,因此实时且准确地对小麦倒伏状况监测有很重要的意义。传统的方法采用手工方式生成数据集,不仅效率低、易出错,而且生成的数据集不准确。针对这一问题,本研究提出了一种基于图像处理的自动数据集生成方法。首先利用无人机在15、46和91 m三个高度采集图像数据;采集完数据后,根据无倒伏、倒伏面积50%的标准对每一块地的小麦倒伏情况进行人工评估;采用三种机器学习(支持向量机、随机森林、K近邻)和三种深度学习(ResNet101、GoogLeNet、VGG16)算法对小麦倒伏检测情况进行分类。结果显示,ResNet101的分类结果优于随机森林,并且在91 m高度采集的数据分类精度并不低于在15 m高度采集的数据。本研究证明了针对在91 m高度采集的无人机图像,采用ResNet101对小麦倒伏率检测是一种有效的替代人工检测的方法,其检测精度达到了75%。

关键词：小麦倒伏率机器学习深度学习数据采集高度无人机 ResNet101

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以金属氧化物为原料改进燃烧法合成γ-LiAlO_2（英文）

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Transactions of Nonferrous metals Society of China 2018年第9期28卷 1793-1800页

作者： Daniel CRUZ H.B.ORTIZ-OLIVEROS L.m.PéREZ-DíAZ R.m.flores-ESPINOSA G.ROSANO-ORTEGA Facultad de Ingeniería Química Benemérita Universidad Autónoma de Puebla14 Sur y San ClaudioCiudad UniversitariaC.P.72570Cd.PueblaMéxico Instituto Nacional de Investigaciones Nucleares Dirección de Investigación TecnológicaApartado Postal 18-102711801 MéxicoDFMéxico Universidad Popular Autónoma del Estado de Puebla 21 Sur no.1103Colonia SantiagoC.P.72410PueblaMéxico

提出一种合成γ-LiAlO_2的替代解决方案—改进燃烧法直接合成γ-LiAlO_2,并将其用于相对简单的反应体系中,原料为非氧化性化合物如Al_2O_3和LiOH,燃料为尿素。采用1:1、1.5:1和2:1的非化学计量Li/Al摩尔比,在900和1000°C下反应5 min,制... 详细信息

提出一种合成γ-LiAlO_2的替代解决方案—改进燃烧法直接合成γ-LiAlO_2,并将其用于相对简单的反应体系中,原料为非氧化性化合物如Al_2O_3和LiOH,燃料为尿素。采用1:1、1.5:1和2:1的非化学计量Li/Al摩尔比,在900和1000°C下反应5 min,制备LiAlO_2,并对其组织和结构进行表征。考察Li/Al摩尔比对材料形貌和高γ射线辐照下材料稳定性的影响。结果表明,所得粉体的晶体结构为?-LiAlO_2和?-LiAlO_2,其取决于Li/Al摩尔比。因此,用该方法可以成功合成微砖状、多面体状和层状?-LiAlO_2,而无需任何后续处理。γ辐照结果表明,所得到的?-LiAlO_2不分解,只形成少量的Li_2CO_3;由此可以确定,辐照会导致固结,不利于氚的有效提取;结果证明,用燃烧法生产高纯度?-LiAlO_2不需要硝酸盐前驱体。

关键词：尿素氧化物燃烧铝酸锂陶瓷

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Atmospheric-pressure dielectric barrier discharge generation by a full-bridge flying capacitor multilevel inverter

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Plasma Science and Technology 2017年第7期19卷 40-49页

作者： Rosendo PE?A-EGUILUZ José A LóPEZ-FERNáNDEZ Antonio mERCADO-CABRERA Bethsabet JARAmILLO-SIERRA Régulo LóPEZ-CALLEJAS Benjamín RODRíGUEZ-méNDEZ Raúl VALENCIA-ALVARADO Allan A flores-FUENTES Arturo E mU?OZ-CASTRO Plasma Physics Laboratory Instituto Nacional de Investigaciones Nucleares Tecnológico de Estudios Superiores de Tianguistenco Universidad Autónoma del Estado de méxico

A new configuration of a resonant full-bridge flying capacitor multicell inverter has been designed and constructed with the aim of achieving an extended output voltage frequency range with low harmonic distortion and reduced semiconductor commutation losses. This configuration was tested as a power supply for two different coaxial dielectric barrier discharge reactors, one of them employed for electric characterization and the other one for inorganic compound elimination in an aqueous solution. Two different gas mixtures, 90% Ar-10% 02 and 80% Ar-20% 02, were individually supplied during the experiments; the results showed a high- efficiency removal of meta-cresol （m-cresol） to the order of 98%, which was obtained by adding more oxygen to the plasma gas mixture.

关键词： plasma applications water pollution plasma sources power supply circuits electricdischarges

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COVID-19 Times: Impact on Information Generation and Data Sharing

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Advances in Internet of Things 2022年第3期12卷 65-87页

作者： Eden Rodríguez-flores Saúl Gómez-manzo Jaime marcial-Quino Roberto Arreguín-Espinosa Eduardo Rodríguez-Bustamante Departamento de Química de Biomacromoléculas Instituto de Química Universidad Nacional Autónoma de México Ciudad de México Mexico Laboratorio de Bioquímica Genética Instituto Nacional de Pediatría Secretaría de Salud Ciudad de México Mexico Investigador Independiente en área de Salud Ciudad de México Mexico Departamento de Bioingeniería Escuela de Ingeniería y Ciencias Tecnológico de Monterrey Campus Ciudad de México Monterrey Mexico

At the beginning of 2020, human activities were interrupted by a new virus, identified as SARS-CoV-2, which causes COVID-19 disease. The scientific area was no exception: for a certain period, researchers around the world were forced to leave their laboratories and work remotely. There was a global necessity for finding alternatives focused on generating knowledge and publishing data, so repositories of scientific information, such as databases, represented strong support. In the specific case of life sciences, different strategies allowed rapid compilation of data and its sharing worldwide. Therefore, in this work, the impact of the SARS-CoV-2 pandemic on the amount of peer-reviewed and published papers during COVID-19 times was analyzed along with the role of databases. Our results pointed out that an increase in the number of papers belonging to different knowledge fields took place, with the medical field being the most significant. On the other hand, the complete genome of the new virus was sequenced, and repositories were created with sufficient data for monitoring, preventing, and controlling its dissemination. This was the case for the generation of vaccines in addition to potential candidates for drugs against COVID-19. However, although in 2021, vaccines allowed us to gradually return to our activities, databases and the generation of other repositories remain a key point for facing new strains and adapting to a new reality. Finally, this paper discusses joint efforts to tackle the obstacles of the pandemic, not only from a medical but also from the point of view regarding the fight against misinformation.

关键词： COVID-19 Laboratories Closure Data Availability Information Repositories Research Papers Infodemics Vaccines Variants and Reopening

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The Potential of Cerebrolysin in the Treatment of Schizophrenia

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Pharmacology & Pharmacy 2014年第7期5卷 691-704页

作者： Gonzalo flores marco Atzori Facultad de Ciencias Universidad Autónoma de San Luis Potosí San Luis Potosí Mexico Laboratorio de Neuropsiquiatría Instituto de Fisiología Universidad Autónoma de Puebla Puebla México

Schizophrenia and psychosis are psychiatric condition whose neural mechanisms are yet incompletely known, and for which pharmacological treatment is too often ineffective in a growing clinical cohort. Recently, dendritic morphological changes in arborization and dendritic spine density in limbic regions has been reported in postmortem tissue from schizophrenic patients and in animal models of schizophrenia, suggesting that the use of medication improving synaptogenesis may be beneficial as additional treatment of psychotic patients. Cerebrolysin (Cbl) is a drug available for clinical with active neuropeptides fragments that mimics the action of endogenous neurotrophic factors such as BDNF, GDNF, CNTF and NGF, which improves the integrity of the neuronal circuits as well as cognitive and behavioral performance by exerting a neuroprotective effect and promoting the generation of new functional synapses. Recent work from our laboratory has shown that Cbl ameliorates synaptic and dendritic pathology in animal models of schizophrenia by increasing synaptic density and restoring neuronal cytoarchitecture. This neuroprotective effect improves the integrity of the neuronal circuits and improves cognitive and behavioral performance. Importantly, Cbl treatment seems to be safe when used in combination with neuroleptics such as risperidone. The present article analyzes the potential of Cbl in the treatment of neurodevelopmental disease, and reviews the current literature on the effects of Cbl in in vivo animal models of neurodevelopmental disorders like schizophrenia.

关键词： Cerebrolysin Neurotrophic Factors Schizophrenia Prefrontal Cortex Hippocampus Amygdala

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Effect of the initial ECAP passes on crystal texture and residual stresses of 5083 aluminum alloy

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International Journal of minerals,metallurgy and materials 2020年第6期27卷 801-808页

作者： L.Romero-Reséndiz A.flores-Rivera I.A.Figueroa C.Braham C.Reyes-Ruiz I.Alfonso G.González Instituto de Investigaciones en materiales Universidad Nacional Autónoma de MéxicoCd.de México 04510México Procédés et Ingénierie en mécanique et matériaux Arts et MétiersParis 75013France Departamento de Diseño y manufactura Facultad de IngenieríaUniversidad Nacional Autónoma de MéxicoPIIT Apodaca 66629México Instituto de Investigaciones en materiales Unidad MoreliaUniversidad Nacional Autónoma de MéxicoMorelia 58190México

To produce a highly refined microstructure,several metals or alloys have been processed via equal-channel angular pressing(ECAP).In this work,the mechanical and microstructural changes of the 5083 aluminum alloy in H11 condition after processed by two ECAP passes were investigated.An ECAP H13 steel die with an inner angle(α)of 120°and outer curvature(β)of 20°was used.The microstructural changes were associated with the loss of texture symmetry.The morphologies of the mg2Si andα-Al(mn,Fe)Si precipitates for the sample at the initial condition were similar to those subjected to two ECAP passes.The peak broadening measured by X-ray diffraction revealed an increment of both grain refinement and microstrain.After the second extrusion pass,the hardness increased by 62%compared with the initial condition.moreover,the heterogeneous hardness behavior was compatible with a highly localized dislocation density.After two ECAP passes,shear parallel bands were observed to be at nearly 45°to the extrusion direction.The evaluation of first-order residual stress as a function of the depth of the analyzed sample displayed compressive or tensile values,depending on the measured face.With the plastic deformation applied,the first and second-order residual stresses exhibited significant increment.Williamson-Hall plots showed positive slopes,indicating an increment in the microstrain.

关键词： aluminum alloy equal-channel angular pressing texture microstructure residual stress

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Graphene Oxide/multilayer-Graphene Synthesized from Electrochemically Exfoliated Graphite and Its Influence on mechanical Behavior of Polyurethane Composites

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materials Sciences and Applications 2018年第7期9卷 565-575页

作者： L. m. flores-Vélez O. Domínguez Faculty of Chemistry UASLP San Luis Potosí México Institute of metallurgy UASLP San Luis Potosí México

Graphene Oxide/multilayer-Graphene (GO-mG) flakes were obtained using an electrochemically exfoliated graphite (GR) electrode from secondary steel-making industry performed in a two-electrode system using tungsten as the counter electrode and GR as the working electrode. The exfoliated GO-mG flakes were processed and incorporated in an elastomeric polyurethane (PU) matrix. The mechanical properties of the PU/GO-mG composites were evaluated and compared with equivalent composites made of PU/GR powder. From experimental data analysis it was concluded that GO-mG flakes were approximately composed of 67 wt% GO and 33 wt% mG. The number of layers in the graphene flakes was estimated to be between 2 and 5 sheets. PU showed a breaking stress of 570 kPa, while the PU/20wt% GR attained a maximum stress of 750 kPa as compared to PU/10wt% GO-mF composite exhibiting a breaking stress of 1060 kPa.

关键词： Electrochemical Exfoliation Graphene Oxide Nanocomposites Polyurethane

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