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Growth of Four Varieties of Coffea arabica L. Biofertilized with Rhizophagus intraradices and Azospirillum brasilense in Nursery

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American Journal of plant Sciences 2023年第5期14卷 552-568页

作者： Zoila C. Anzueto-Herón Juan F. Aguirre-Medina Juan F. Aguirre-cadena cadena-iñiguez pedro Faculty of Agronomic Sciences—Campus V Autonomous University of Chiapas Villaflores México Faculty of Agricultural Sciences—Campus iV Autonomous University of Chiapas Huehuetán México instituto Nacional de investigaciones Agrícolas y pecuarias Campo Experimental Centro Chiapas Ocozocoautla México

Coffee production has decreased due to environmental and management factors. The current plantations are old and unproductive, also due to the rust problem, caused by the fungus Hemileia vastatrix Berk & Br. Furthermore, the shade in the production systems has decreased with the consequent increase in soil erosion, in addition to the increase in agrochemicals. Currently, the planting of new varieties with resistance to the fungus is increasing. Furthermore, it has been shown that various biofertilized perennial crops in nursery favor their growth. in this study, the effect of applying two beneficial microorganisms, Rhizophagus intraradices and/or Azospirillum brasilense, to the planting of four varieties of Coffea arabica L. was evaluated. The coffee varieties marseillase, geisha, sarchimor and costa rica 95 were established in bags with the following treatments: 1) control, 2) R. intraradices, 3) A. brasilense, 4) R. intraradices + A. brasilense. Morphological and physiological yield components were recorded 168 days after transplanting. Data was analyzed statistically and differences between treatments were compared according to Tukey (p ≤ 0.05). The results indicate that individual or combined biofertilization of microorganisms favors dry matter allocation compared to the control and the same is differentially assigned to the stem and root. The Specific Leaf Area (SLA) also showed differential response between applications of the microorganisms, in two varieties it increased when they were applied alone and in the others when they were applied together.

关键词： Rhizophagus intraradices Azospirillum brasilense Coffee Varieties

Hierarchical dispatch of multiple microgrids using nodal price:an approach from consensus and replicator dynamics

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Journal of Modern power Systems and Clean Energy 2019年第6期7卷 1573-1584页

作者： Miguel A.VELASQUEZ Oscar TORRES-pEREZ Nicanor QUiJANO Angela cadena Department of Electrical and Electronics Engineering Universidad de los AndesBogotaColombia

A hierarchical approach for the energy management of geographically close microgrids connected through a dedicated AC power network is proposed in this paper.The proposed approach consists of a two-layer energy management system(EMS)for networked microgrids.in the lower layer,each micro grid solves its own economic dispatch problem through a distributed model predictive control approach that respects capacity limits and ramp-rate constraints of distributed generation.in the upper layer,the energy trading in the network of microgrids decides how to optimally trade the energy based on the marginal cost information from the lower layer in order to improve global optimization objectives,e.g.,social welfare.in order to solve the trading problem,a consensusbased algorithm and a replicator dynamics algorithm are proposed assuming that the marginal cost function of the microgrid is known and linear.it is shown that both algorithms converge to the same solution,which is equivalent to the minimization of operation costs.The consensus-based algorithm is extended in order to tackle more general marginal cost functions and trading network constraints.Moreover,the effect of ramp constraints and network limits is studied.Simulations show the effectiveness of the proposed algorithms for three interconnected microgrids with different characteristics.

关键词： Consensus Economic dispatch Hierarchical control Networked microgrids Ramp limits Replicator dynamics

Evaluation of bias on the assessment of diet breadth of herbivorous insects using molecular methods

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insect Science 2017年第2期24卷 194-209页

作者： Gissela De la cadena Anna papadopoulou Jean-Michel Maes Jesus Gomez-Zurita Animal Biodiversity and Evolution Institut de Biologia Evolutiva (CSIC-Univ. Pompeu Fabra) Barcelona Spain Department of integrative Ecology Estacion Biologica de Donana (EBD-CSIC) Seville Spain Museo entomologico de Leon Leon Nicaragua

The interactions between herbivores and their host plants play a key role in ecological processes. Understanding the width and nature of these interactions is funda- mental to ecology and conservation. Recent research on DNA-based inference of trophic associations suggests that the host range of phytophagous insects in the tropics may be wider than previously thought based on traditional observation. However, the reliability of molecular inference of ecological associations, still strongly dependent on pCR and thus exposed to the risk of contamination with environmental DNA, is under debate. Here, we explored alternative procedures to reduce the chance of amplification of external, nondiet DNA, including surface decontamination and analysis of mid/hind guts, comparing the results with those obtained using the standard protocol. We studied 261 specimens in eight species of Neotropical Chrysomelidae that yielded 316 psbA-trnH intergenic spacer sequences （cpDNA marker of putative diets） from unique and multiple-band pCR results. The taxonomic identity of these sequences was inferred using the automated pipeline BAGpipe, yielding results consistent with 31 plant families. Regardless of the proto- col used, a wide taxonomic spectrum of food was inferred for all chrysomelid species. Canonical Correspondence Analysis using these data revealed significant differences at- tributed mainly to species （expectedly, since they represent different ecologies）, but also to treatment （untreated vs. cleaned/gut samples） and pCR results （single vs. multiple bands）. Molecular identification of diets is not straightforward and, regardless of the species＇ niche breadth, combining approaches that reduce external contamination and studying multiple individuals per species may help increasing confidence in results.

关键词： food-webs gut content insect plant interaction molecular ecology molec-ular taxonomy psbA-trnH intergenic spacer

influence of Vanadium Additions on the performance of Mo<sub>3</sub>Si

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Materials Sciences and Applications 2021年第7期12卷 345-352页

作者： i. Rosales-cadena Center for Research in Engineering and Applied Sciences Cuernavaca Mexico

Several molybdenum silicides based alloys were produced by arc cast method with different vanadium additions. The microstructures revealed mainly single phase in samples with precipitation of second phases segregated to the grain boundaries. Lattice parameter and density measurements with different V concentrations have been correlated with lattice distortion. Mechanical properties studies were carried out, showing a decreasing behavior in microhardness while fracture toughness value increases at intermediate concentrations. Results indicated that vanadium alloying produces a significant effect on grain growth behavior and second phase precipitation.

关键词： Silicides indentation Hardness Fracture Toughness Lattice parameter

Dispersion of niquel on the microstructure in magnesium based alloys for hydrogen storage

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Journal of Magnesium and Alloys 2013年第4期1卷 292-296页

作者： A.A.Zaldıvar-cadena i.Dıaz-pena J.G.Cabanas-Moreno Universidad Autonoma de Nuevo Leon Av.Universidad s/nFacultad de Ingenierıa CivilSan Nicolas de los Garza N.L.C.P.66451Mexico instituto politecnico Nacional UPALMCol.LindavistaC.P.07338 Mexico D.F.Mexico

Mg–Xwt.%Ni(X=5 and 20)alloys have been prepared by mechanical alloying using milling times of 15 and 30 h in a planetary ball milling to know the effects of magnesium with the addition of Ni as catalyst,dispersion on the microstructure,area surface and the efficiency of hydrogen storage.SEM-EDS,XRD and imageJ^(■)software have been used to characterize the microstructure and chemical composition of the alloys.Hydriding experiments were performed as batch-type tests at 200,250 and 300℃ under 2 Mpa H2 pressure during 30 min.These experiments resulted in varying amounts of MgH2 in the hydrided powders depending on composition and hydriding conditions.The best results point to an optimum Ni dispersion,which in turn depends on Ni content and milling time.

关键词： Hydrogen storage Magnesium Niquel Alloy Characterization

Wear Evaluation of Copper-Nickel-Aluminum Alloys under Extreme Conditions

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Journal of Minerals and Materials Characterization and Engineering 2023年第1期11卷 16-26页

作者： Rene Guardian isai Rosales-cadena Constancio Diaz-Reyes Juan Antonio Ruiz-Ochoa Center for Research in Engineering and Applied Sciences Autonomous University of State of Morelos Cuernavaca Mexico Faculty of Sciences of the Enginery and Technology UABC Tijuana Mexico

Cu-Ni-Al alloys at different concentrations were obtained using a high frequency induction melting unit, keeping a balance in the nominal compositions. Light alloys are important to be used in industrial applications. Aluminum additions result in a positive hardness increment of the ternary alloys in comparison with the binary Cu-Ni alloys. Generalized wear mechanisms of the alloys with low aluminum content are basically type abrasive, while samples with 5 and 10 at.% Al present an oxidative-adhesive wear mechanism. Wear results have indicated that aluminum addition affects positively the wear resistance, mainly in samples with high aluminum content product of the creation during the test of different oxides corresponding to the elements present in the alloys.

关键词： Copper Nickel Alloys Hardness Mechanical properties Heat Treatment

Temporal-spatial segregation among hummingbirds foraging on honeydew in a temperate forest in Mexico

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Current Zoology 2011年第1期57卷 56-62页

作者： Carlos LARA Vanessa MARTiNEZ-GARCiA Raul ORTiZ-pULiDO Jessica BRAVO-cadena Salvador LORANCA Alex CORDOBA-AGUiLAR Laboratorio de Ecologfa de la Conducta Centro Tlaxcala de Biologfa de la Conducta UAT-UNAM Km 1.5 carretera Tlaxcala- Puebla s/n Colonia Xicohtencatl Apdo. Postal 262 Tlaxcala Tlaxcala 90070 Mexico Laboratorio de Ecologfa de poblaciones. Centro de investigaciones Biologicas. Universidad Autonoma del Estado de Hidalgo Mexico Departamento de Quimica y Biologia. Universidad de las Ameficas-puebla. Cholula Puebla Mexico Departamento de Ecologfa Evolutiva. lnstituto de Ecologfa Universidad Nacional Autonoma de Mexico Distrito Federal Mexico

Spatial and temporal variation in interactions between hummingbirds and plants have often been examined, and hummingbirds and insects are known to indirectly interact in networks of nectar plants. in a highland temperate forest in Hidalgo, Mexico some oak trees were heavily infested by honeydew-producing insects (family Margarodidae, tribe Xylococcini, genusStrigmacoccus) and the honeydew was consumed by hummingbirds. Here using survival analysis we investigate how the honeydew produced by dense populations of these margarodids is temporally and spatially partitioned by hummingbirds. We also measured the availability and quality of honeydew exudates, and then we recorded the time until a bird visited and used such resources. Four hummingbird species consumed this resource (Atthis eloisa, Hylocharis leucotis, Colibri thalassinusandEugenes fulgens). Data from 294 hours of observation on seven focal trees suggested temporal and spatial segregation among visiting birds according to body size and territorial behavior during the most honeydew-limited time. Hummingbird species differed in the daily times they foraged, as well as in the location where honeydew-producing insects were visited on the trees. Temporal and spatial segregation among hummingbird species is interpreted as an adaptation to reduce the risk of aggressive encounters. This may facilitate multispecies coexistence and allow these birds to exploit honeydew more effectively.

关键词：温带森林墨西哥蜂鸟蜜露觅食时空蜜源植物和空间

Entire Whitening of Apple Trees to increase Chill Units in Regions of Warm Temperatures during the Fall-Winter Seasons

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American Journal of plant Sciences 2022年第8期13卷 1100-1115页

作者： Alejandro Zermeño-González J. A. Gil-Marín H. Ramírez-Rodríguez A. i. Melendres-Alvarez M. cadena-Zapata Departamento de Riego y Drenaje Universidad Autonóma Agraria Antonio Narro Saltillo México Departamento de Horticultura Universidad Autonóma Agraria Antonio Narro Saltillo México Departamento de Maquinaria Agrícola Universidad Autonóma Agraria Antonio Narro Saltillo México

Different studies have shown that global warming and climate change have increased the planet’s temperature in different locations. For the apple-growing farmers, this may have a negative impact on the accumulations of chill units when the air temperature during the fall-winter season increases. When the entire trees are covered with a reflective material, the wood temperature may decrease. Therefore, the objective of this study was to evaluate the effect of whitening (with calcium hydroxide) the entire apple trees (Malus domestica Borkh) after defoliation, on the branches and trunks’ internal temperature (under the bark), the accumulation of chill units (CU), its effects on fruit yield and quality and the relation with the use of thidiazuron (TDZ) (inducer of budbreak). The study was conducted during the fall-winter seasons of 2019-2020 and 2020-2021. The results of this study showed that at the hours of the highest incidence of solar radiation, the internal temperature of the whitened trunks and leaves decreases up to 9°C and 6°C respectively. The accumulated CU during the time of the study, of the whitened branches were up to 81% higher than the ones recorded on the branches with no whitening;while the CU was lost at the hours of highest solar radiation (due to a high temperature) were up to 37.2% smaller. Entire tree whitening increased up to 26% of the yield per tree compared to the application of TDZ. No statistical difference in fruit quality was observed between whitened trees and those with no whitening but with the application of thidiazuron.

关键词： Malus domestica Borkh Chill Units Whitening Calcium Hydroxide Budbreak

Blood Flow Simulation in the Femoral Artery

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Journal of Electronic Science and Technology 2018年第3期16卷 269-279页

作者： Camilo A.Naranjo Andrés F.Villa Juan C.Vélez Ricardo A.prato Alberto J.cadena Juan p.Tello ipATEC institute CONICETBariloche R8400 integra iT Bogotá 602 the Electronic and Electric Engineering Department Universidad del NorteBarranquilla 1569 the institute of Mathematics Universidad de AntioquiaMedellin 050010 the Cardiology Department Clínica de la CostaBarranquilla 080020

This paper presents the development of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the distributions of the blood pressure and flow velocity in multiple instants of time and different places of the femoral artery and thus determine the current condition of the blood vessels. The velocity field shows a laminar behavior,where, the velocity is higher in the center of the artery and decreases as the blood flow approaches artery walls. in spite of all artery and blood flow properties not being considered, the values of pressure and velocity obtained are within the normal ranges. Finally the model is used to verify if there exist irregularities in the blood flow in both healthy subjects and sick patients.

关键词： Blood flow femoral artery finite elements Navier-Stokes pressure velocity