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World Journal of nano Science and Engineering 2012年第4期2卷 213-218页

作者： Jacobo Martínez-Reyes Lucia Graciela Díaz Barriga-Arceo Luis Rendón-Vazquez Reynaldo Martínez-Guerrero néstor romero-partida Eduardo Palacios-González Vicente Garibay-Febles Jaime Ortiz-López IMP-Molecular Engineering Program México City México national Polytechnic Institute (IPn) ESFM UPALM México City México national Polytechnic Institute (IPn) ESIQIE UPALM México City México ROMFER S.A. de C.V. México City México UnAM-FCiencias México City México

In the present work the synthesis of C60 produced in a conventional microwave oven from the decomposition of camphor resin is reported. The polycrystalline structure of the sample was determined by X-Ray Diffraction (XRD), the sample showed several phases, the main phase corresponds to fullerene C60 ordered in a Face-Centered Cubic structure (FCC), with two more structures: one orthorhombic system and the other the monoclinic system coexisting also with graphite 2H phase. It was observed in a Scanning Electron Microscopy (SEM), that the sample formed thin films of stacked carbon. Whereas in a High Resolution Transmission Electron Microscopy (HRTEM), measurements in Bright Field mode revealed that the main phase of the material is C60 ordered in FCC structure and the elemental composition and atomic bonding state can be determined by analyzing the energy with the electron microscope by Elesctron Energy- Loss Spectroscopy (EELS), technique allowed confirm all the phase C60 established with XRD observations.

关键词： Microwave-Assisted Synthesis Carbon Film Fullerene

A Value for Games Defined on Graphs

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Applied Mathematics 2024年第5期15卷 331-348页

作者： néstor Bravo Departamento de Matemá ticas Universidad de Guanajuato Guanajuato Mexico

Given a graph g=( V,A ) , we define a space of subgraphs M with the binary operation of union and the unique decomposition property into blocks. This space allows us to discuss a notion of minimal subgraphs (minimal coalitions) that are of interest for the game. Additionally, a partition of the game is defined in terms of the gain of each block, and subsequently, a solution to the game is defined based on distributing to each player (node and edge) present in each block a payment proportional to their contribution to the coalition.

关键词： Graph Theory Values for Graphs Cooperation Games Potential Function

Pig Reproductive and Respiratory Syndrome Virus (PRRSV) Does not Attach to Boar Sperm;It Affects Only the Velocity Pattern and the Mobility Pattern

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Journal of Biosciences and Medicines 2024年第4期12卷 216-228页

作者： néstor Méndez Palacios netzi naidí Mendez Palacios Felicitas Vázquez Flores José Alfredo Galicia Domínguez Edgar Guadalupe Beltrán Rosas Maximino Méndez Mendoza Facultad de Medicina Veterinaria and Zootecnia-Benemé rita Universidad Aut&#243noma de Puebla Puebla Mexico Independent Advisor in the Porcine Area Puebla Mexico

The purpose of the study was to evaluate the sperm viability of semen infected with PRRSV viral particles, observing the effect of the Virus on the motility of boar sperm. The work was carried out at the FMVZ-BUAP Genetics and Reproduction Laboratory. 5 stallions were used. Each sample contained 1 × 106 sperm, the PRRS virus strain was ATCC-VR-2332 (0, 102, 104 and 106 copies of RnA/mL in triplicate), it was observed daily at the CASA;Hamilton Thorne®. Cells with MT (P n days 1, 3, 5, 7 and 10 of evaluation with 201 ± 7.3, 167 ± 10.1, 165 ± 14.6, 134 ± 8.2 and 120 ± 8.8, respectively. The % MP between control and virus concentrations (P ≥ 0.05). The LCV on day 1 and 7 PI at 10X2 and 10X6 (P ntrol. In the Correlation Matrix, where it is observed that there is a correlation between VSL and VAP, VSL and VCL, VCL and ALH, VAP with ALH. There is a correlation of VSL and ALH, STR and ALH. In this study there were (P ≤ 0.01) in the VCL, in the concentrations (102) 162.81 ± 10.65 and (106) 177.12 ± 5.77 vs 193.04 ± 4.62 of control. This indicates that altering these parameters would be related to fertility and the PRRS virus affects the LCV. Regarding the VSL, it was observed that the sperm infected with viruses 102, 104 and 106 of 48.00 ± 3.38, 49.88 ± 1.83 and 50.55 ± 2.24 Vs. 56.66 ± 1.68 of control respectively, the control would have greater possibilities of fertilizing the oocyte. In this study, it was found (P ≤ 0.01) in the VAP with 102 of 77.26 ± 5.16, 104 with 83.35 ± 2.41 and 106 with 81.29 ± 3.14 vs the control with 90.56 ± 2.07. Regarding the ALH there is (P 4 with 8.70 ± .26 and 106 with 9.64 ± 0.23 vs control 8.50 ± 0.27. The presence of different concentrations of PRRSV in boar semen induces changes in different types of sperm motility. Infection of ejaculates with the PRRS virus affects sperm motil

关键词： PRRSV Boar Sperms Velocity Pattern and Mobility Pattern

Effectiveness of a home-environmental intervention package and an early child development intervention on child health and development in high-altitude rural communities in the Peruvian Andes: a cluster-randomised controlled trial

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Infectious Diseases of Poverty 2022年第3期11卷 95-96页

作者： néstor nuño Daniel Mäusezahl Jan Hattendorf Hector Verastegui Mariela Ortiz Stella M.Hartinger Department of Public Health and Epidemiology Swiss Tropical and Public Health InstituteKreuzstrasse 2CH-4123AllschwilSwitzerland 不详

Background: Unsafe drinking water,poor sanitation and hygiene,exposure to household air pollution and low cognitive and socio-emotional stimulation are risk factors affecting children in low-and middle-income countries.We implemented an integrated home-environmental intervention package(IHIP),comprising a kitchen sink,hygiene education and a certified improved biomass cookstove,and an early child development(ECD)programme to improve children´s health and developmental outcomes in the rural high-altitude Andes of Peru.Methods: We conducted a one-year cluster-randomised controlled trial among 317 childrennths divided into 4 arms(IHIP+ECD,IHIP,ECD,and Control)and 40 clusters(10 clusters per arm).ECD status(socio-emotional,fine and gross motor,communication,cognitive skills,and an overall performance)measured with the Peruvian Infant Development Scale and the occurrence of self-reported child diarrhoea from caretakers were primary outcomes.Secondary outcomes included the occurrence of acute respiratory infections and the presence of thermo-tolerant faecal bacteria in drinking water.The trial was powered to compare each intervention against its control arm but it did not allow pairwise comparisons among the four arms.Primary analysis followed the intention-to-treat principle.For the statistical analysis,we employed generalised estimating equation models with robust standard errors and an independent correlation structure.Results: We obtained ECD information from 101 children who received the ECD intervention(individually and combined with IHIP)and 102 controls.Children who received the ECD intervention performed better in all the domains compared to controls.We found differences in the overall performance(64 vs.39%,odd ratio(OR):2.8;95%confidence interval(CI):1.6–4.9)and the cognitive domain(62 vs 46%,OR:1.9;95%CI:1.1–3.5).Data analysis of child morbidity included 154 children who received the IHIP intervention(individually and combined with ECD)and 156 controls.We recorded 110,666 child-days of information on d

关键词： Child development Clinical trial Diarrhoea Improved biomass cookstoves Peru WASH

Gastrointestinal tuberculosis:An autopsy-based study

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Infectious Medicine 2023年第2期2卷 122-127页

作者： Julio Cesar Mantilla Juan JoséChaves Ferney Africano-Lopez néstor Blanco-Barrera Marta Juliana Mantilla Department of Pathology Universidad Industrial de SantanderBucaramanga 680002Colombia Department of Pathology Hospital Universitario de SantanderBucaramanga 680002Colombia Department of Pathology Fundación Universitaria de Ciencias de la SaludBogotá111411Colombia Department of Gastroenterology Gastrocenter and Medical SpecialitiesIpiales 524061Colombia Department of Gastroenterology Universidad Militar Nueva GranadaBogotá250240Colombia Department of Rheumatology Universidad de la SabanaChía 250001Colombia

Background:Tuberculosis is a disease of great relevance since it is one of the leading causes of morbidity and mortality worldwide.Gastrointestinal tuberculosis is an unusual presentation.It is defined as the involvement of any segment of the digestive tract,associated viscera,and peritoneum.The study’s main objective is to collect information from autopsies of patients diagnosed with gastrointestinal tuberculosis in a Pathology reference center in Colombia.Methods:This is a retrospective and descriptive study of autopsy reports.A total of 4,500 autopsies were performed between January 2004 and December 2020.The inclusion criteria were authorization of a family member following local law regulations and a final autopsy diagnosis of gastrointestinal tuberculosis using microscopic visualization.Results:Forty-eight patients with gastrointestinal tuberculosis autopsies were included in our study.Most of the patients were male(n=35,72.9%)with a median age of 40.5 years old.Human immunodeficiency virus infection history was reported in 28 cases(58.33%).The most affected gastrointestinal tract site was the terminal ileum.Ulcers and thickened epithelium were common autopsies macroscopic findings.Tuberculosis multiorgan compromise was a relevant finding in patients with gastrointestinal tuberculosis.Conclusions:Gastrointestinal tuberculosis is a disease of great importance,being its diagnosis a clinical challenge.Underdiagnosis can be reported in a high percentage of cases,so autopsy diagnosis can help reveal more accurate data about this condition.

关键词： Gastrointestinal tuberculosis Autopsy Forensic pathology Infections Colombia

China's Solution to Global Governance Crisis

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Contemporary World 2022年第3期 35-38页

作者： néstor Restivo Working Group on China at Argentine Council for International Relations

In today’s highly globalized world, countries and regions are ever more closely intertwined with more complex relations. As COVID-19 pandemic changes international order in a profound way, the challenges facing global governance system have intensified. There is an urgent call for change. In this context, China offers a new solution to improving global governance by proposing the vision of building a community with a shared future for mankind.

关键词： intensified today profound

The pitfalls in electrocatalytic nitrogen reduction for ammonia synthesis

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Journal of Energy Chemistry 2021年第10期30卷 149-154,I0005页

作者： Huimin Liu néstor Guijarro Jingshan Luo Institute of Photoelectronic Thin Film Devices and Technology Solar Energy Research CenterKey Laboratory of Photoelectronic Thin Film Devices and Technology of TianjinMinistry of Education Engineering Research Center of Thin Film Photoelectronic TechnologyRenewable Energy Conversion and Storage CenterNankai UniversityTianjin 300350China Institute of Electrochemistry University of AlicanteAlicante E-03080Spain

Ammonia synthesis by electrocatalytic nitrogen reduction reaction(EC-nRR)has gained momentum in recent years fueled by its potential to operate at ambient conditions,unlike the highly energyintensive yet long-standing Haber-Bosch process.However,the large disparity of the yields and Faradic efficiencies reported for EC-nRR raises serious concerns about the reliability of the experimental results.In this perspective,we elaborate on the potential sources of error when assessing EC-nRR and update the testing protocols to circumvent them,and more importantly,we pose a general call for consensus on ammonia production analysis and reporting to lay the solid foundations that this burgeoning field requires to thrive.

关键词： Electrocatalytic nitrogen reduction Ammonia synthesis Pitfalls Standard protocols

Glacier reconstruction of La Covacha Massif in Sierra de Gredos(central Spain) during the Last Glacial Maximum

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Journal of Mountain Science 2019年第6期16卷 1336-1352页

作者： néstor CAMPOS David PALACIOS Luis M.TAnARRO Department of Geography Complutense University of Madrid

A paleoglacier reconstruction during the Last Glacial Maximum(LGM) is presented for a high mountain area of La Covacha massif in Sierra de Gredos(Iberian Central System) in central Spain. The moraines that, according with the previous literature, had formed during the global LGM, were mapped through photo interpretation of digital aerial photographs and 3D images and detailed field surveys. The topography of the paleoglaciers was estimated using a simple steady-state model that assumed a perfectly plastic ice rheology, reconstructing the theoretical ice profiles and obtaining the ice thickness of the glaciers during the LGM. The reconstruction of the glaciers was carried out using automated and semi-automated physically-based models, obtaining more realistic results with semi-automated models. According to our study, the paleoglaciers in the study area covered an area of 34.79 km^2 during the global LGM, with a maximum ice thickness of 366 meters in La Vega gorge, a total volume of 34.25 × 108 m^3 and a mean paleoELA of 1932 meters. Most of the ice(~82%) was in paleoglaciers facing north, and the rest was in paleoglaciers with other orientations. This emphasizes the importance of orientation in relation to glacier dynamics and ice accumulation. The results obtained in the calculation of paleoELAs during the global LGM in Gredos are average compared to the Iberian mountains of the northwest where the values were much lower, and with respect to those of the Southwest, much higher. This demonstrates the importance of the exposure of Mediterranean mountains to the humidity sources coming from the nW during the global LGM, as is the case at present.

关键词： Glacier reconstruction Paleoglacier Ice thickness Equilibrium line altitude Iberian Central System

Sol–gel La2O3–ZrO2 mixed oxide catalysts for biodiesel production

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Journal of Energy Chemistry 2018年第2期27卷 565-572页

作者： Daniela Salinas Catherine Sepúlveda néstor Escalona J.L.GFierro Gina Pecchi Departamento de Fisicoquimica. Facultad de Ciencias Quimicas Universidad de Concepcion Post Office 160-C Concepcion Chile Departamento de Quimica Facultad de Ciencias Universidad del Biobio Post Office 5-C Concepcion Chile Departamento Ingenieria Quimica y Bioprocesos Escuela de lngenieria Pontificia Universidad Catolica de Chile Avda. Vicuria Mackenna 4870 Maeul Santiago 7820436 Chile Centro de Investigacion en nanotecnolagia y Materiales Avanzados (CIEn-UC) Pontificia Universidad Catolica de Chile Post Office 306 Santiago Chile Departamento de Quimica Fisica Facultad de Quimica Pontificia Universidad Catolica de Chile Post Offce 306 Santiago Chile Instituto de Catalisis y Petroleoquimica CSIC 28049 Madrid. Espana

Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel production.Greater biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.

关键词： La2O3 -ZrO2 Sol-gel Biodiesel Canola oil Transesterification

Relict glacial landscape in the Sierra Baguales Mountain Range(50°-51°S):evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes

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Journal of Mountain Science 2017年第2期14卷 282-295页

作者： ARAOS.JoséMiguel LE ROUX.Jacobus Philiphus GUTIERREZ.néstor Mauricio Department of Geology FCFMUniversidad de ChilePlaza Ercilla#803SantiagoChile Department of Geography Faculty of Social Sciences.Universidad Alberto HurtadoUienfuegos#41SantiagoChile Department of Geology FCFMUniversidad de Chile.Andean Geothermal Centre of ExcellencePlaza Ereilla#803SantiagoChile

The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range(SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field(SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift,which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum(LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower elevations.This can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26m Equilibrium Line Altitude(ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio(AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography.

关键词：安第斯山脉冰川类型景观重建证据塞拉利昂动力学非气候因素塔