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Antifeedant Activity of Caesalpinia coriaria Essential Oil Against Incisitermes marginipennis (Latreille)

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phyton-International Journal of Experimental Botany 2021年第3期90卷 907-920页

作者： Cesar B.Ramírez-López Rita Beltrán-Sánchez Alistair Hernández-Izquierdo JoséLuis Salvador-Hernández eduardo salcedo-pérez Rosa E.del Río Mauro M.Martínez pacheco Instituto de Investigaciones Químico Biológicas Universidad Michoacana de San Nicolás de HidalgoMorelia58030Mexico Departamento de Botánica y Zoología CUCBA Universidad de GuadalajaraNextipac45200Mexico

This study scrutinized the possibility of finding toxicant or deterrent plant metabolites against the dry wood termite Incisitermes marginipennis(Latreille).plant deterrent agents act as repellents or antifeedants to prevent wood decay and increase its useful *** potential of the tree Caesalpinia coriaria(Fabaceae)as a biological source of molecules with deterrent effects against the dry wood termite was assessed by a phytochemical fractionation guided by repellence and antifeedant *** gas chromatography-mass spectrometry analysis of the leaf essential oil showed geraniol to be one of the major components and its repellent and antifeedant effects were *** had only an antifeedant effect without affecting the body weight or survival of the dry wood *** the leaf essential oil,geraniol did not exhibit a repellency *** in-silico approach of the activity of acetylcholinesterase in interaction with geraniol resulted in an affinity energy of−7.5 Kcal/*** interacted with the amino acid tyrosine 324 located in the enzyme’s active site while citronellol(negative control)interacted with tryptophan 83 located adjacent to the active *** deterring terpenes have not been implemented for the preservation and restoration of wood products exposed to the attack of the dry wood ***,they are an important natural control alternative.

关键词： Termite geraniol repellent antifeedant deterrent

Effect of grain recrystallization on stir zone and mechanical property behavior of TRIp 780 steel

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Journal of Iron and Steel Research International 2020年第2期27卷 188-196页

作者： Gladys perez-Medina Hugo Lopez Argelia Miranda-perez eduardo Hurtado-Delgado postgraduate Studies Mexican Corporation in Materials ResearchSaltillo Coahuila 25290Mexico Materials Department University of Wisconsin-MilwaukeeMilwaukeeWI 53201USA

Electron backscatter diffraction(EBSD)and transmission electron microscopy were used to determine the presence of retained austenite and displacive-type phase transformation in the stir zone of friction stir welding(FSW).Severe plastic deformations occurred in the stir zone where there was an increase in the temperature attributed to the FSW process and subsequently a grain *** the recrystallization phenomena,the formation of grain evolution development in steels was resolved using *** addition,a tensile test was carried out in order to reveal the results of mechanical *** was found that the fracture zone occurred in the stir zone with an ultimate tensile strength of 587 Mpa,a decrease of 267 Mpa compared with that of the base *** this result,it is evident that the fracture exhibits numerous elongated dimples,distributed homogeneously,and certain locations contain cleavage fractures due to differences in the microstructure of the base *** profile tests of the welding regions were conducted,and the results showed that the stir zone was present with elevated hardness(near 350 HV).Characterization techniques revealed that the austenite-to-martensite transformation occurred in the stir zone,resulting in a loss of mechanical properties in the joint.

关键词： Friction welding Transformation-induced plasticity steel Stir zone Mechanical property Tensile test

Urbanization has opposite effects on the territory size of two passerine birds

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Avian Research 2020年第2期11卷 191-199页

作者： Roselvy Juárez eduardo Chacón‑Madrigal Luis Sandoval Escuela de Biología Universidad de Costa RicaCP:11501‑2060San PedroMontes de OcaSan JoséCosta Rica Ambientey Desarrollo Universidad ZamoranoCarretera a Danlíkm 30Francisco MorazánHonduras.

Background:Urban expansion has been identified as one of the leading drivers of biodiversity change or *** birds,urbanization is specifically related to survival,breeding success,and territory *** how different birds adjust territory size in response to urbanization is essential for their conservation in urban environments and to better understand why some species are lost and others persist under this *** evaluated the effect of urbanization on the territory size of an urban avoider species,White-eared Ground-Sparrow(Melozone leucotis),and an urban adapter species,House Wren(Troglodytes aedon),at five Costa Rican ***:We measured the size of 30 ground-sparrow and 28 wren territories using a total of 296 h of *** followed each individual for at least 1 h per day for at least 2 days of two consecutive years,and geo-referenced their *** size was estimated using the minimum convex polygon *** measured the urban surfaces(roads,buildings,any other paved area,soccer fields,lawns,and gardens with short grass)within ***:Ground-sparrow territories were larger at the highly urbanized site than at the non-urbanized *** territories were larger at the low urbanized site than at the highly urbanized *** found a positive relationship between urban surface and territory size for the ground-sparrow,but not for the ***:Our results showed that not all birds adjust territory size in the same way in response to *** showed that urban avoiders probably need to defend larger territories in urban environments to find all the resources required to survive because urban environments may provide insufficient resources such as food or *** adapters on the other hand defend smaller territories in urban environments because even small territories may provide sufficient *** results suggest specific behavioral adaptations developed by Neotropical birds inha

关键词： House Wren Melozone leucotis Troglodytes aedon Urban adapter Urban avoider Urban-rural gradient Territory size White‑eared Ground‑Sparrow

3′-UTR of the SARS-CoV-2 genome as a possible source of piRNAs

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Genes & Diseases 2023年第3期10卷 668-670页

作者： María Teresa Hernández-Huerta Laura pérez-Campos Mayoral Carlos Alberto Matias-Cervantes Carlos Romero Díaz Eli Cruz parada eduardo pérez-Campos Mayoral Rafael Baltiérrez-Hoyos Margarito Martínez Cruz Gabriel Mayoral Andrade eduardo pérez-Campos CONACyT Faculty of Medicine and SurgeryAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico Research Center Faculty of Medicine UNAM-UABJOAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 8020Mexico National Technology of Mexico/IT Oaxaca Oaxaca de JuárezOaxaca 68030Mexico

SARS-CoV-2 is the causal agent of the COVID-19 pandemic. This is a single-stranded RNA beta-coronavirus that is comprised of a 5′ and 3′-untranslated region (UTR) in its non-coding RNA (ncRNA) region. The p-element-induced wimpy testis (pIWI)-interacting RNAs (piRNAs) are ncRNA sequences that bind to transposons and interfere with the translation of new genes. Here, we search for short sequences in the non-coding regions, corresponding to 28 nucleotides (nt). These start from a uracil and have a conserved region of at least 10 nt of homology with the previously reported piRNAs. The aim of this work was to identify piRNA-like sequences in the 3′-UTR of SARS-CoV-2 from the reported Wuhan patient's genome sequence (GenBank: MN908947.3).

关键词： piRNA sequences piRNAs

The detrimental effects of lipopolysaccharideinduced neuroinflammation on adult hippocampal neurogenesis depend on the duration of the pro-inflammatory response

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Neural Regeneration Research 2019年第5期14卷 817-825页

作者： Martha pérez-Domínguez Evangelina ávila-Mu?oz eduardo Domínguez-Rivas Angélica Zepeda Departamento de Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones Biomédicas.Universidad Nacional Autónoma de MéxicoCDMX

Adult hippocampal neurogenesis is a finely tuned process regulated by extrinsic factors. Neuroinflammation is a hallmark of several pathological conditions underlying dysregulation of neurogenesis. In animal models, lipopolysaccharide(LpS)-induced neuroinflammation leads to a neurogenic decrease mainly associated to the early inflammatory response. However, it is not well understood how the neuroinflammatory response progresses over time and if neurogenesis continues to be diminished during the late neuroinflammatory response. Moreover, it is unknown if repeated intermittent administration of LpS along time induces a greater reduction in neurogenesis. We administered one single intraperitoneal injection of LpS or saline or four repeated injections(one per week) of LpS or saline to young-adult mice. A cohort of new cells was labeled with three 5-bromo-2-deoxyuridine injections(one per day) 4 days after the last LpS injection. We evaluated systemic and neuroinflammation-associated parameters and compared the effects of the late neuroinflammatory response on neurogenesis induced by each protocol. Our results show that 1) a single LpS injection leads to a late pro-inflammatory response characterized by microglial activation, moderate astrocytic reaction and increased interleukin-6 levels. This response correlates in time with decreased neurogenesis and 2) a repeated intermittent injection of LpS does not elicit a late pro-inflammatory response although activated microglia persists. The latter profile is not accompanied by a continued longterm hippocampal neurogenic decrease. Hereby, we provide evidence that the neuroinflammatory response is a dynamic process that progresses in a milieu-dependent manner and does not necessarily lead to a neurogenic decrease, highlighting the complex interaction between the immune system and neurogenesis.

关键词： dentate gyrus subgranular zone inflammation microglia astrocytes IL-6 cytokines cell proliferation neural progenitor cells immature neurons long-term short-term adult hippocampal neurogenesis

Interaction of piRNA-like sequences from the 3′-UTR of SARS-CoV-2 with mRNA regions

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Genes & Diseases 2023年第6期10卷 2282-2284页

作者： Laura pérez-Campos Mayoral María Teresa Hernández-Huerta Carlos Romero Díaz Carlos Alberto Matias-Cervantes eduardo pérez-Campos Mayoral Margarito Martínez Cruz Juan de Dios Ruiz-Rosado Edgar Gustavo Ramos Martínez Marco Antonio Sánchez Medina eduardo pérez-Campos Research Center Faculty of Medicine UNAM-UABJOAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico CONACyT Faculty of Medicine and Surgery.Autonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico National Technology of Mexico(TecNM)/IT Oaxaca Oaxaca de JuárezOaxaca 68030Mexico The Research Institute at Nationwide Children's Hospital Columbus 43205USA Facultad de Química Universidad Nacional Autónoma de MéxicoCoyoacán 04510Mexico

piwi-interacting RNAs(piRNAs of 26-32 nt in length)regulate gene expression,epigenetics,and transcriptional and post-transcriptional processes.1 In humans,piRNAs are expressed in germline and somatic tissues,and generally have a uracil at the 5'-end(position+1),an adenine at the+10 position,and are 2'-0 methylated at the 3'-end.2 Onice piRNAs form the RNA-induced silencing complex(RISC)with pIWl proteins,they serve as guides to find their complementary sequences of the target mRNA,thus initiating their *** Wuhan patient's genome is approximately 265 nucleotides(nts)in its 3'-UTR;piRNAs-like sequences have been reported in this region.3 Our objective was to search,through bioinformatics,for mRNA sequences that were homologous to the reverse complementary of the previously reported piRNA-like sequences from the 3'-UTR of SARS-Cov-2,3 and identify the possible interaction between them.

关键词： sequences complementary initiating

A computer vision system for early detection of anthracnose in sugar mango(Mangifera indica)based on UV-A illumination

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Information processing in Agriculture 2023年第2期10卷 204-215页

作者： Leonardo Ramırez Alberto Carlos eduardo Cabrera Ardila Flavio Augusto prieto Ortiz Facultad de Ingenierı´a Universidad Nacional de ColombiaBogota´D.C.111321Colombia

The present work describes the development of a computer vision system for the early detection of anthracnose in sugar mango based on Ultraviolet A illumination(UV-A).Anthracnose,a disease caused by the fungus Colletotrichum sp,is commonly found in the fruit of sugar mango(Mangifera indica).It manifests as surface defects including black spots and is responsible for reducing the quality of the ***,it decreases its commercial *** more detail,this study poses a system that begins with image acquisition under white and ultraviolet ***,it proposes to analyze the Red,Green and Blue color information(R,G,B)of the pixels under two types of illumination,using four different methods:RGB-threshold,RGB-Linear Discriminant Analysis(RGBLDA),UV-LDA,and *** analysis produces an early semantic segmentation of healthy and diseased areas of the mango *** results showed that the combination of the linear discriminant analysis(LDA)and UV-A light(called UV-LDA method)in sugar mango images allows early detection of ***,this method achieves the identification of the disease one day earlier than by an expert with respect to the scale of anthracnose severity implemented in this work.

关键词： Sugar mango Anthracnose LDA UV-A light Grading Image processing

Non-linear modeling of kinetic and equilibrium data for the adsorption of hexavalent chromium by carbon nanomaterials:Dimension and functionalization

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Chinese Journal of Chemical Engineering 2019年第4期27卷 912-919页

作者： Miguel de la Luz-Asunción eduardo E.pérez-Ramírez Ana L.Martínez-Hernández Victor M.Castano Víctor Sánchez-Mendieta Carlos Velasco-Santos Facultad de Quimica Universidad Autonoma del Estado de Mexico Km. 12 de la carretera Toluca-Atlacomulco C.P. 50200 San Cayetano Toluca Estado de Mexico Mexico Tecnologico Nacional de Mexico-Instituto Tecnologico de Queretaro Division de Estudios de Posgrado e Investigacion Av. Tecnologico s/n esq. GraL Mariano Escobedo Col. Centro Historico C.P. 76000 Santiago de Queretaro Queretaro Mexico Centro de Fisica Aplicada y Tecnologia Avanzada Universidad Nacional Autonoma de Mexico Boulevard Juriquilla 3001 Queretaro 76230 Mexico

The adsorption capacities for the removal of hexavalent chromium from aqueous solutions by six carbon nanomaterials have been evaluated. Single-walled and multi-walled carbon nanotubes as received and after oxidation treatment, graphene oxide and reduced graphene oxide are the materials with different dimension and functionalization compared in this research. Carbon nanotubes have been modified using hydrogen peroxide as oxidizing agent under microwave radiation. The oxidation treatment on carbon nanotubes has a positive effect increasing the adsorbent–adsorbate interaction. Rate-controlling mechanisms and equilibrium data are analyzed using non-linear models. Non-linear method is proposed as the most suitable method for determining the kinetic and equilibrium parameters. The values of adsorption energy(E) obtained from the Dubinin–Radushkevich isotherm,have been found around 0.371 and 0.870 k J·mol-1, indicating physical adsorption. Therefore, the pseudo-second order model represents better the kinetic experimental data. The results show that the Langmuir isotherm provides a slightly better fit to the experimental data compared with the Freundlich isotherm, indicating homogeneous distribution of active sites on carbon nanomaterials and monolayer adsorption. The separation factors RLare found in the range of 0–1, suggesting that the adsorption process is suitable for all adsorbents. The mechanisms for hexavalent chromium removal have been proposed as electrostatic interactions and hydrogen bonding.

关键词： Carbon nanotubes Graphene Adsorption Hexavalent chromium Kinetic

Conifer establishment after the eruption of the paricutin volcano in central Mexico

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Forest Ecosystems 2022年第1期9卷 71-82页

作者： Jesús eduardo Sáenz-Ceja Blanca Lizeth Sáenz-Ceja J.Trinidad Sáenz-Reyes Diego Rafael pérez-Salicrup Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autéonoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autónoma de MéxicoAntigua Carretera a Patzcuaro 8701 Col.Ex hacienda San Joséde la Huerta58190MoreliaMexico Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasCampo Experimental UruapanAv.Latinoamericana 1101Col.Revolución60500UruapanMexico

Background:Volcanic eruptions have large effects on forest ecosystems and create new substrates,triggering primary succession *** paricutín volcano,born in central-western Mexico,erupted between 1943 and *** the cessation of the eruptive activity,plant colonization began on the lava flows and tephra deposits,including the conifer species that dominate the surrounding mature *** study aims to reconstruct the history of the establishment of conifer trees on the substrates created by the paricutín ***:16 sampling plots were established along three transects with northern,southern,and south-western aspects,located every 250 m from the preserved forest to the volcanic *** cores from 400 conifer trees were extracted and their age was determined by cross-dating annual tree *** order of the species colonization and the tree establishment,abundance,and dominance patterns were ***,the influence of the distance from the mature forests and the inter-annual climatic conditions on the temporal tree establishment pattern was ***:Eight pine and one fir species have been established since 1970,only 18 years after the end of the eruptive ***,tree establishment increased by 12.9%annually after 1995,with the youngest tree in our sample getting established in *** did not find a well-defined temporal and spatial pattern of species arrival,which suggests that colonization occurred randomly,although the four pine species that were established early became the most abundant and *** establishment was not influenced by the distance from the mature forest,and wet inter-annual conditions did not enhance pulses of tree recruitment,exhibiting a continuous tree establishment ***:Conifer species have shown a great capacity for colonizing volcanic substrates created by the paricutín eruption,which suggests that tropical montane conifers can regenerate rapidly under high-magni

关键词： Age structure Dendrochronology Lava flow primary succession Tropical montane forest