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Cytogenetical Changes among Polyembryonic(PEm)and Non-PEm Maize Plants

Phyton-International journal of Experimental Botany 2021年第1期90卷 87-97页

作者： A.A.Román-Calzoncit F.Ramírez-Godina j.Sánchez-Laureano A.C.Flores-Gallegos j.espinoza-velázquez R.Rodríguez-Herrera School of Chemistry Universidad Autónoma de Coahuila.Blvd.V.Carranza e Ing.JoséCárdenas V.s/n.Col.República Ote.C.P.25280.SaltilloCoahuilaMéxico Plant Breeding Department Universidad Autónoma Agraria Antonio NarroBlvd.Antonio Narro 1923BuenavistaSaltilloMéxico

Polyembryony in maize(PEm)contributes to improving the nutritional properties of the grain,as well as an increase in yield,since it generates multiple plants per seed,opening the possibility of developing new ***,it is unknown whether polyembryony in maize is the product of chromosomal *** on the above,in this research a cytogenetic study was proposed to verify if chromosomal abnormalities are related to the maize *** a meiotic study,maize genotypes with variable proportions of polyembryony(PEm),from the UA-IMM-BAP population and non-PEm(monoembryonic)maize were used,while for a mitosis analysis,30 families of maternal half-siblings(MHS)from two different populations with high polyembryony,denominated as BHP(brachytic,high polyembryony)and NHP(normal height,high polyembryony)were *** these genotypes were planted in the Buenavista Agricultural Experimental Station-UAAAN at Saltillo,Coahuila,*** frequency of PEm was estimated in all *** was found that the polyembryony occurs at frequencies from 34 to 66%in the D-02,BHP group,and from 13 to 21%in the segregating groups of the G3-0202 and *** squash technique was used for both cytogenetic *** meiotic irregularities in maize chromosomes were detected,such as irregular association of 10%of chromosomes in metaphase 1,and agglomeration of chromatin in 100%of the *** addition,pollen viability was estimated by the staining technique with 1%acetocarmine dye,and it was found that the polyembryonic ones have pollen viability of 100%.In meiosis in prophase,I sub-phase diakinesis,ten pairs of bivalents were confirmed,confirming 2n=20,both in non-PEm and PEm maize,corroborating mating,and balanced segregation,without the presence of univalent or *** the chromosomal count carried out in cells in mitosis,only in the BHP-200 polyembryonic family was registered two out of twenty triploid *** condition of ploidy is atypical in

关键词： Zea mays irregular meiosis mitosis chromosomes chromatin polyploidy

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Performance Improvement of Artificial Neural Network Model in Short-term Forecasting of Wind Farm Power Output

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journal of Modern Power Systems and Clean Energy 2020年第3期8卷 484-490页

作者： Sergio velázquez Medina Ulises Portero Ajenjo Department of Electronics and Automatics Engineering Universidad de Las Palmas de Gran CanariaCampus de Tafira s/n35017 Las Palmas de Gran CanariaCanary IslandsSpain School of Industrial and Civil Engineering University of Las Palmas de Gran CanariaCampus de Tafira s/n35017 Las Palmas de Gran CanariaCanary IslandsSpain

Due to the low dispatchability of wind power,the massive integration of this energy source in power systems requires short-term and very short-term wind power output forecasting models to be as efficient and stable as possible.A study is conducted in the present paper of potential improvements to the performance of artificial neural network(ANN)models in terms of efficiency and ***,current ANN models have been developed by considering exclusively the meteorological information of the wind farm reference station,in addition to selecting a fixed number of time periods prior to the *** this respect,new ANN models are proposed in this paper,which are developed by:varying the number of prior 1-h periods(periods prior to the forecasting hour)chosen for the input layer parameters;and/or incorporating in the input layer data from a second weather station in addition to the wind farm reference *** has been found that the model performance is always improved when data from a second weather station are *** mean absolute relative error(MARE)of the new models is reduced by up to 7.5%.Furthermore,the longer the forecasting horizon,the greater the degree of improvement.

关键词： Artificial neural networks(ANN) wind power forecasting model performance wind power output

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Tropical Cyclones in Nicaragua:Historical Impact and Contemporary Exposure to Disaster Risk

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International journal of Disaster Risk Science 2024年第4期15卷 579-593页

作者： Gema velásquez‑espinoza Irasema Alcántara‑Ayala Faculty of Sciences and Engineering National Autonomous University of Nicaragua14172 Unan-ManaguaNicaragua Postgraduate Programme in Geography National Autonomous University of Mexico(UNAM)04510 Mexico CityMexico Institute of Geography National Autonomous University of Mexico(UNAM)04510 Mexico CityMexico

In tropical regions such as Nicaragua, the population's vulnerability to hazards has escalated in recent decades. This increase in vulnerability has led to a surge in disasters, particularly those triggered by intense hurricanes. The implications at the national level are still poorly understood. The aim of this article has, therefore, been two-fold. First, to present a historical review of the direct effects of tropical cyclones on society in Nicaragua from 1852 to 2020. Second, to analyze the statistical probabilities of future hurricane-spawned high winds over Nicaragua. Data on cyclones hitting Nicaragua's coasts were collected, including direct effects, wind speed, pressure, category, direction, and time of landfall. A database was created to classify intensity based on wind speed and frequency. Between 1852 and 2020, Nicaragua experienced 58 tropical cyclones with varying degrees of intensity between September and November. The trajectories of six past hurricanes were considered here regarding the areas that might have been under potential threat. Three zones of influence were delimited along each trajectory according to three wind intensities and the trajectory of these hurricanes. The consequent exposure of each Nicaraguan department and autonomous region was established. The findings are essential to delimitating priority areas for attention regarding the likely impact of tropical cyclones, mainly category 4 and 5 hurricanes. Public officials and the general public can use these data to identify the pressing need for enhanced strategies to mitigate disaster risk and avoid potential disasters.

关键词： Exposure Historical impact Hurricanes Nicaragua Tropical cyclones Vulnerability

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Novel kinetic model for the simulation analysis of the butanol productivity of Clostridium acetobutylicum ATCC 824 under different reactor configurations

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Chinese journal of Chemical Engineering 2018年第4期26卷 812-821页

作者： Hugo I.velázquez-Sánchez Ricardo Aguilar-López Center of Research and Advances Studies of the National Polytechnic Institute (CINVESTAV) Biotechnology and Bioengineering DepartmentAv. National Polytechnic Institute 2508 Col. San Pedro Zacatenco

Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel *** this regard,mathematical modelling and simulation analysis are tools that can serve as the base for process engineering development of biological *** this work,a novel phenomenological kinetic model of Clostridium acetobutylicum ATCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells:single stage batch operation,fed-batch,single stage Continuous Stirred Tank Reactor(CSTR)and multistage CSTRs with and without biomass *** proposed model achieved a linear correlation index r^2=0.9952 and r^2=0.9710 over experimental data for free and immobilized cells *** predicted maximum butanol concentration and productivity obtained were 13.08 g·L^(-1)and 1.9620 g·L^(-1)·h^(-1)respectively,which represents an increase of 1.01%and 990%versus the currently developed industrial scale process reported currently into the *** results provide a reliable platform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.

关键词： Biofuels Butanol Clostridium acetobutylicum Mathematical modelling Process configurations

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Dendritic spine degeneration:a primary mechanism in the aging process

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Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo Flores Leonardo Aguilar-Hernández Fernado García-Dolores Humberto Nicolini Andrea judith Vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de Ciencias Forenses(INCIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de Medicina Genómica(INMEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

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Embryo and Endosperm Phytochemicals from Polyembryonic Maize Kernels and Their Relationship with Seed Germination

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Phyton-International journal of Experimental Botany 2022年第5期91卷 929-941页

作者： j.David García-Ortíz Rebeca González-Centeno María Alejandra Torres-Tapia j.A.Ascacio-Valdés joséespinoza-velázquez Raúl Rodríguez-Herrera Food Research Department School of ChemistryAutonomous University of CoahuilaSaltillo25280México Plant Breeding Department Universidad Autonoma Agraria Antonio Narro(UAAAN)Saltillo25315México

Because of the growing worldwide demand for maize grain,new alternatives have been sought for breeding of this cereal,e.g.,development of polyembryonic varieties,which agronomic performance could positively impact the grain yield per unit area,and nutritional *** objectives of this study were to(1)determine the phytochemicals present in the embryo and endosperm of grain from maize families with high,low,and null polyembryony frequency,which were planted at different locations,and(2)state the relationship between these compounds and seed *** extracted phytochemicals from corn were identified by *** results showed that the genotype with the highest presence of phytochemicals was the brachytic population with high polyembryony called“BAP”,which also required less water during the germination *** number of phytochemicals in both embryo and endosperm tissues was not related to the sowing location where they came from or the type of *** number of different phytochemicals depended on the grain tissue from where they were *** chemical compounds found in the different maize tissues were related to the development of the plant,either in roots or nibs because these are mainly associated with the lignin synthesis.

关键词： Zea mays L HPLC-MS locations kernels phytochemicals

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Alternative beneficiation of tantalite and removal of radioactive oxides from Ethiopian Kenticha pegmatite–spodumene ores

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International journal of Minerals,Metallurgy and Materials 2017年第7期24卷 727-735页

作者： Berhe Goitom Gebreyohannes velázquez del Rosario Alberto Abubeker Yimam Girma Woldetinsae Bogale Tadesse School of Materials Science and Engineering Jimma Institute of Technology Jimma University P.O. Box 378 Jimma Ethiopia Chemistry Department College of Natural and Computational Science Mekelle University P.O. Box 823 Mekelle Ethiopia School of Chemical and Bio Engineering AAiT Addis Ababa University P.O. Box 1176 Addis Ababa Ethiopia Research and Development Directorate Federal Democratic Republic of Ethiopia Ministry of Mines Petroleum and Natural Gas P.O. Box 486 Addis Ababa Ethiopia Department of Mining Engineering and Metallurgical Engineering Western Australian School of Mines Curtin University Egan St Kalgoorlie WA 6430 Australia

The beneficiation methods for Ethiopian Kenticha pegmatite–spodumene ores were assessed through mineralogical and quantitative analyses with X-ray diffraction（XRD） and energy-dispersive X-ray fluorescence（EDXRF）. The tantalite in the upper zone of the Kenticha pegmatite–spodumene deposit is 58.7wt% higher than that in the inner zone. XRD analysis revealed that the upper zone is dominated by manganocolumbite, whereas the inner zone is predominantly tantalite-Mn. Repeated cleaning and beneficiation of the upper-zone ore resulted in concentrate compositions of 57.34wt% of Ta_2O_5 and 5.41wt% of Nb_2O_5. Washing the tantalite concentrates using 1vol% KOH and 1 M H_2SO_4 led to the removal of thorium and uranium radioactive oxides from the concentrate. The findings of this study suggest that the beneficiation and alkaline washing of Kenticha pegmatite–spodumene ores produce a high-grade export-quality tantalite concentrate with negligible radioactive oxides.

关键词： beneficiation manganocolumbite pegmatite-spodumene radioactive oxides tantalite

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The Limit Case of a Domination Property

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Acta Mathematica Sinica,English Series 2012年第3期28卷 463-468页

作者： Magdalena LEMANSKA juan A. RODRíGUEZ-velzquez Ismael G. YERO Department of Technical Physics and Applied Mathematics Gdańsk University of Technology Departament d’Enginyeria Informàtica i Matemàtiques Universitat Rovira i Virgili Departament d'Enginyeria Informàtica i Matemàtiques Universitat Rovira i Virgili

The domination number γ,（G） of a connected graph G of order n is bounded below by

关键词： Dominating set domination number

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Reporter gene systems for the identification and characterization of cancer stem cells

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World journal of Stem Cells 2021年第7期13卷 861-876页

作者： NohemíSalinas-jazmín Arely Rosas-Cruz Marco velasco-velázquez Department of Pharmacology School of MedicineUniversidad Nacional Autónoma de MéxicoMexico City 04510Mexico

Cancer stem cells(CSCs)are tumor cells that share functional characteristics with normal and embryonic stem *** have increased tumor-initiating capacity and metastatic potential and lower sensitivity to chemo-and radiotherapy,with important roles in tumor progression and the response to ***,a current goal of cancer research is to eliminate CSCs,necessitating an adequate phenotypic and functional characterization of *** have been developed to identify,enrich,and track CSCs,many of which distinguish CSCs by evaluating the expression of surface markers,the initiation of specific signaling pathways,and the activation of master transcription factors that control stemness in normal *** review and discuss the use of reporter gene systems for identifying *** that are under the control of aldehyde dehydrogenase 1A1,CD133,Notch,Nanog homeobox,Sex-determining region Y-box 2,and POU class 5 homeobox can be used to identify CSCs in many tumor types,track cells in real time,and screen for ***,reporter gene systems,in combination with in vitro and in vivo functional assays,can assess changes in the CSCs *** present relevant examples of these systems in the evaluation of experimental CSCs-targeting therapeutics,demonstrating their value in CSCs research.

关键词： Cancer Gene reporter systems Cancer stem cells Pluripotency transcription factors Anticancer drugs Preclinical analysis Cancer stem cells marker

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Modeling and multi-objective optimization of a gasoline engine using neural networks and evolutionary algorithms

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第9期14卷 657-670页

作者： joséD. MARTíNEZ-MORALES Elvia R. PALACIOS-HERNáNDEZ Gerardo A. velázquez-CARRILLO Faculty of Engineering Autonomous University of San Luis PotosiSan Luis Potosi 78290 Mexico Faculty of Science Autonomous University of San Luis PotosiSan Luis Potosi 78290 Mexico Mechatronics Department Monterrey Institute of Technology and Higher EducationMexico D. F. 01389 Mexico

In this paper, a multi-objective particle swarm optimization （MOPSO） algorithm and a nondominated sorting genetic algorithm II （NSGA-II） are used to optimize the operating parameters of a 1.6 L, spark ignition （SI） gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide （CO）, hydrocarbons （HC）, and nitrogen oxides （NOx）, which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks （ANNs） were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms： NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively.

关键词： Engine calibration Multi-objective optimization Neural networks Multiple objective particle swarm optimization(MOPSO) Nondominated sorting genetic algorithm II (NSGA-II)

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