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Foliar Analysis as an Estimate on the Nutritional State of Conilon Coffee Plantations on Cambisoils

Journal of Life Sciences 2014年第2期8卷 181-187页

作者： alberto perez diaz Emesto Castaneda Hidalgo Salvador Lozano Trejo Carlos alberto Bustamante Gonzailez Ramon Antonio Rivera Espinosa Geraldo Rodriguez Ortiz Gloria Martha Martin Alonso Cerelino Roblesperez Guillermo Acosta Coutin alberto Fernandez Turro Centro de Estudios de Cafe y Cacao Universidad de Guantanamo Guantanamo 95300 Cuba Instituto Tecnologico del Valle de Oaxaca Ex Hacienda de Nazareno Xoxocotlan 712320 Mexico Instituto de Investigaciones Agroforestales UCTB-Tercer Frente Santiago de Cuba 92700 Cuba Instituto Nacional de Ciencias Agricolas San Jose de las Lajas Mayabeque 32700 Cuba Universidad de Ciencias Pedagogicas "Raul Gomez Garcla " Guantanamo 95100 Cuba

The objective of this paper relies on the establishment of the sampling moment and the nutritional state of the species Conilon coffee (Coffea canephora) cultivated in Cambisoils. The effect of different rates of nitrogen fertilization was also studied in the leaves concentrations of N, at randomized complete block designs (N 0 = 0; N 1 = 50; N 2 = 100; N 3 = 150 and N 4 = 200 kg?ha -1 of N) in presence of P (40 kg?ha -1 of P 2 O 5 ) and K (160 kg?ha -1 of K 2 O), with four replicates. The samples were carried out in the months of March (flower blossoming stage), June (fruits growing stage), September (grain development) and December (maturation) in all treatments. Foliar analysis carried out in the month of June (fruits growing stage) for the purpose of establishing critical nutrient range values for N, settling down approaches of interpretation of the same one for the Conilon coffee plantations on Cambisoils. The biggest percentages in the yields are obtained with leaves containing N between 2.80% and 3.10%, a value below 2.80% N which they associated with indicative percentages of stable maximum yield that did not surpass the limits of the adequate nutrients supply.

关键词：咖啡树种植园营养状况叶面果实生长期评估随机区组设计营养状态

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A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael perez-Gonzalez Christian Gomez-Solis Luis Armando diaz-Torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 nm.Microscopy images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential direction.TiWNi NPs presented a mixture of anatase/rutile phases with cubic structure.The performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible light.The results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),respectively.Thus,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF degradation.Raman/absorbance measurements confirmed the presence of such defects.Moreover,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their degradation.The results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

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Description of a Propulsion Unit Used in Guiding a Walking Machine by Recognizing a Three-point Bordered Path

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Chinese Journal of Mechanical Engineering 2016年第6期29卷 1157-1166页

作者： NUNEZ-ALTAMIRANO Diego A JUAREZ-CAMPOS Ignacio MARQUEZ-perez Lucia FLORES-diaz Ociel School of Mechanical Engineering Universidad Michoacana de San Nicolas de Hidalgo Morelia Michoacan Mexico

A reconfigurable propulsion unit based on the Peaucellier-Lipkin mechanism has the ability to describe exact straight or curved paths depending on the selected ratio between the lengths of two of its links. The Peaucellier-Lipkin mechanism with one degree of freedom is transformed into a more sophisticated parallel kinematic chain by including four more degrees of freedom. The resulting propulsion unit is able to adapt its kinematic structure and reach instant centers of rotation, in accordance with the presence of three points that border a geometric path. A laser sensor mounted on the body of the machine detects each point. Once the machine has detected the exact location of the border of the road, it walks along a curve parallel to that border. Although the proposed research describes only one propulsion unit or leg, the methodology can be applied to all the legs of the walking machine. The novel 5-DOF leg is able to reach different centers of rotation, providing either the concave or convex arcs that satisfy the basic principle of displacement of walking machines.

关键词： Propulsion unit Peaucellier-Lipkin walking machine straight line mechanism.

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A Survey of the Representations of Rational Ruled Surfaces

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Journal of Systems Science & Complexity 2021年第6期34卷 2357-2377页

作者： YUAN Chun-Ming perez-diaz Sonia SHEN Li-Yong KLMM Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Grupo ASYNACS Dpto.de Fisica y MatematicasUniversidad de Alcala28871-Alcala de HenaresMadridSpain

The rational ruled surface is a typical modeling surface in computer aided geometric design.A rational ruled surface may have different representations with respective advantages and disadvantages.In this paper,the authors revisit the representations of ruled surfaces including the parametric form,algebraic form,homogenous form and Plucker form.Moreover,the transformations between these representations are proposed such as parametrization for an algebraic form,implicitization for a parametric form,proper reparametrization of an improper one and standardized reparametrization for a general parametrization.Based on these transformation algorithms,one can give a complete interchange graph for the different representations of a rational ruled surface.For rational surfaces given in algebraic form or parametric form not in the standard form of ruled surfaces,the characterization methods are recalled to identify the ruled surfaces from them.

关键词： Birational transformation characterization implicitization parametrization rational ruled surface reparametrization

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A technical and socioeconomic approach to estimate forest residues as a feedstock for bioenergy in northern Mexico

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Forest Ecosystems 2019年第4期6卷 312-322页

作者： Guadalupe Carrasco-diaz Gustavo perez-Verdin Jonathan Escobar-Flores Marco Antonio Marquez-Linares Instituto Politecnico Nacional CIIDIR Dgo.

Background: Forest residues can be a feasible alternative for converting energy into fuels, electricity, or heat.Compared to other second-generation bioenergy sources, they do not compete for food, are relatively cheap,abundant in forest-rich areas, and more importantly their energy balance is close to zero. Biomass estimations can help design energy strategies to reduce fossil fuels dependency. Because of the land property distribution in Mexico,biomass estimations should consider not only the physical availability, but also the willingness of landowners to extract such raw materials.Methods: This study presents a methodological approach for evaluating the potential use of forest residues as a feedstock to generate bioenergy in northern Mexico. Remote sensing and field forest inventory were used to estimate the quantity and distribution of forest residues. In addition, a discrete choice analysis evaluated landowners’ preferences towards bioenergy development, including the most important factors that influence their willingness to extract their products and the expected price.Results and conclusions: Considering both physical and socio-economic aspects, results showed that about59,000 metric tons per year could be available in the study area. The vast majority of landowners surveyed are willing to extract forest residues, as long as they are presented with extraction plans with the highest income. However, many showed concerns about the environmental impacts this activity can have on soils,plants, and fauna. These results can help evaluate the potential of these resources for bioenergy development.

关键词： Bioenergy Choice experiments Forest landowners Forest residues Remote sensing

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Controlled building of CdSe@ZnS/Au and CdSe@ZnS/ Au2S/Au nanohybrids

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Nano Research 2015年第7期8卷 2271-2287页

作者： Raquel E. Galian Pilar diaz Antonio Ribera Alejandro Rincon-Bertolin Said Agouram Julia perez-Prieto Instituto de Ciencia Molecular (ICMol) Universidad de Valencia c/ Catedrdtico Jose Beltran 2 46980 Paterna Valencia Spain Department of Applied Physics and Electromagnetism Dr. Moliner 50 Universidad de Valencia 461 00 Burjassot Valencia Spain

The addition of Au3. to spherical amine-capped CdSe@ZnS nanoparticles in toluene at room temperature and under darkness can lead to ternary CdSe@ZnS/Au nanohybrids. We demonstrate that this happens only when the nanoparticles possess a relatively thin ZnS shell, thus showing that thickness plays a key role in gold deposition on the CdSe@ZnS nanoparticle surface. Our hypothesis is that the amine ligand acts as the reductant of Au3＋ ions into Au＋ ions, whose affinity for sulfur would keep them at the CdSe@ZnS surface. This interaction stabilizes the Au＋ ion, making it less prone to reduction than a non-coordinated Au＋ ion. In CdSe@ZnS with a thin shell, Au＋ ions at the surface of, or most probably within, the ZnS shell cause the transfer of Cd2＋ ions into the solution. Subsequently, the core Se2- anion, which is a better reductant than the shell S2- reduces Au＋ ions to Au（0）, and large gold nanoparticles （AuNPs） are quickly deposited on the CdSe@ZnS surface in room temperature process, leading to ternary CdSe@ZnS/Au nanohybrids. In solution, these ternary nanohybrids progressively transform into quaternary CdSe@ZnS/Au2S/Au nanohybrids due to the reaction of the shell S2- anion with the remaining Au＋ at the CdSe@ZnS surface, thus leading to the growth of Au2S nanoparticles on the CdSe@ZnS surface while Zn concomitantly leaches from the nanohybrid into the solution. Photoirradiation of the heterostructures with visible light enhances their emission efficiency. Comparatively, irradiation of the precursors, i.e., CdSe@ZnS nanoparticles, causes a drastic decrease in their emission accompanied by a blue shift of their emission maximum. The optical properties of these nanohybrids were analyzed by absorption and fluorescence （steady-state and time-resolved） spectroscopy, and the composition of the samples and the chemical states were determined by energy dispersive X-ray spectroscopy （EDX） and X-ray photoelectron spectroscopy （XPS）, respectively. Finally, the structural and morphological characterizations of the nanohybrid

关键词： heterostructures semiconductor nanoparticle metallic fluorescence time-resolved studies

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FedIDS:a federated cloud storage architecture and satellite image delivery service for building dependable geospatial platforms

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International Journal of Digital Earth 2018年第7期11卷 730-751页

作者： J.L.Gonzalez-Compean Victor J.Sosa-Sosa Arturo diaz-perez Jesus Carretero Ricardo Marcelin-Jimenez Cinvestav-Tamulipas Ciudad VictoriaMexico ARCOS Research Group University Carlos IIIMadridSpain UAM Iztapalapa CDMX and associated to InfotecMexico

Earth observation satellites produce large amounts of images/data that not only must be processed and preserved in reliable geospatial platforms but also efficiently disseminated among partners/researchers for creating derivative products through collaborative workflows.Organizations can face up this challenge in a cost-effective manner by using cloud services.However,outages and violations of integrity/confidentiality associated to this technology could arise.This article presents FedIDS,a suite of cloud-based components for building dependable geospatial platforms.The Fed component enables organizations to build shared geospatial data infrastructure through federation of independent cloud resources to withstand outages,whereas IDS avoids violations of integrity/confidentiality of images/data in sharing information and collaboration workflows.A FedIDS prototype,deployed in Spain and Mexico,was evaluated through a study case based on a satellite imagery captured by a Mexican antenna and another based on a satellite imagery of a European observation mission.The acquisition,storage and sharing of images among users of the federation,the exchange of images between Mexican and Spanish sites and outage scenarios were evaluated.The evaluation revealed the feasibility,reliability and efficiency of FedIDS,in comparison with available solutions,in terms of performance,storage consume and integrity/confidentiality when sharing images/data in collaborative scenarios.

关键词： Satellite imagery Earth observation archives spatial data infrastructure collaborative workflows security reliability

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Comparison of clinical outcomes between unrelated single umbilical cord blood and"ex-vivo"T-cell depleted haploidentical transplantation in children with hematological malignancies

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World Journal of Pediatrics 2021年第6期17卷 609-618页

作者： Carmen Gomez-Santos Marta Gonzalez-Vicent Blanca Molina Natalia Deltoro Blanca Herrero Julia Ruiz Antonio perez-Martinez Miguel A diaz Department of Pediatrics Hematopoietic Stem Cell Transplantation UnitHospital Infantil Universitario"Nino Jesus"Menedez Pelayo 6528009 MadridSpain Hospital Infantil Universitario"La Pa"Madrid MadridSpain

Background Over the last two decades,umbilical cord blood(UCB)and haploidentical transplantation(HaploHSCT)have emerged as alternative sources of hematopoietic stem cell for allogeneic transplantation.There are few retrospective studies and no prospective studies comparing both types of alternative transplantation in pediatric patients.Results We analyzed the data of 134 children with hematological malignancies who received a hematopoietic stem cell transplantation from a single umbilical cord blood(UCB)(n=42)or an"tex-vivo"T-cell depleted transplant from a haploi-dentical-related donor(HaploHSCT)(n=92)between 1996 and 2014.Hematological recovery was faster after HaploHSCT than the UCB transplant group(median times to neutrophil and platelet recovery:13 vs.16 days,10 vs.57 days,respectively)(P<0.001).The HaploHSCT group had a significantly early immune reconstitution based on NK and CD8+T cells compared with the UCB group.However,after the first year post-transplantation.HaploHSCT had a lower number of CD4+ T and B lymphocytes compared with the UCB transplant recipients.The cumulative incidence of TRM was 29±8%in the HaploHSCT group versus 40±5%in the UCB group.Relapse incidence was 21±7%in the HaploHSCT group and 19±8%in the UCB group.Probability of DFS was 58±8%in the HaploHSCT group versus 40±9%in the UCB group(P=0.051).Conclusions TCD haploidentical transplant is associated with advantages in terms of engraftment and early immune reconstitution kinetics.TCD haploidentical transplant was associated with lower incidence of infectious and non-infectious complications,especially in the early phases of the transplant compared with UCB transplant recipients.However,there are no advantages in transplant outcomes compared with UCB transplant.

关键词： Children Cord blood transplant Hematologic malignancies Immune reconstitution TCD haploidentical transplant

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Infuence of elemental composition in environmental impacts of steel

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Journal of Iron and Steel Research(International) 2020年第5期27卷 598-607页

作者： E.Batuecas C.Mayo R.diaz F.J.perez Thermal and Fluid Engineering Department Carlos III University of Madrid28911 LeganesMadridSpain Chemical and Materials Engineering Department Complutense University of Madrid28040 MadridSpain Technical Sciences and Engineering UDIMA University28400 Collado VillalbaMadridSpain。

The environmental behavior of four steels was analyzed.In the operation phase of concentrating solar power plants,steels withstand high temperature because of its contact with molten salts.Hence,choosing the steel type for the molten salt tanks remains a great challenge.In the cold tank,carbon steel is usually used although an approach with low chromium content steel is being studied for these applications.Likewise,in high temperature applications,such as hot store tank,austenitic stainless steel is the most frequent choice.However,ferritic steel is being considered as a promising material in these applications.As many researchers studied the steel technical properties without considering their environmental damages,this work aimed to introduce the environmental aspects into the material choice by using the life cycle assessment technique.On one hand,the results showed the environmental adequacy of carbon steel against low chromium content steel.On the other hand,the results obtained in those steels suitable in high temperature application revealed signifcant environmental benefts from the ferritic steel instead of the austenitic steel.

关键词： Renewable energy Concentrating solar power Life cycle assessment Molten salt Ferritic steel Austenitic steel

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Emerging roles of microglia cells in the regulation of adult neural stem cells

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Neuroimmunology and Neuroinflammation 2016年第1期3卷 204-206页

作者： Eduardo Lira-diaz Oscar Gonzalez-perez Laboratory of Neuroscience School of PsychologyUniversity of ColimaColima 28040Mexico Medical Sciences PhD Program School of MedicineUniversity of ColimaColima 28040Mexico

MICROGLIA CELLS Microglia cells are antigen presenting cells with myeloid origin that constituted approximately 10%of all glial cells of the adult mouse brain.^([1])In the early embryo,the microglial precursors are located in the yolk sac and progressively migrate throughout the primitive brain.^([2])In the adult brain,some of microglial cells derive from the bone marrow,but this process only takes place when the brain is lesioned.^([1])Microglial cells can display 4 morphological and functional stages:(1)resting microglia;(2)active microglia;(3)phagocytic microglia;and(4)senescent microglia.

关键词： neural migrate adult

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