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Food and Nutrition Sciences 2013年第4期4卷 445-453页

作者： Adriana Gámbaro Ana C. Ellis v.ctor Prieto Department of Biometrics Statistics and Computer Science School of Agronomy Universidad de la República Montevideo Uruguay Sensory Evaluation Laboratory Food Science and Technology Department School of Chemistry Universidad de la República Montevideo Uruguay

Unlike the case in Mediterranean countries, where olive oil consumption is driven by habit or tradition, in a population where olive oil consumption rates are considerably low, it appears reasonable to suppose that the initial decision to buy a fairly expensive product—as is the case with olive oil in the Uruguayan market—may result from an individual’s overall interest in health-related issues and/or their acquaintance with relevant nutritional properties of the particular product—in this case, olive oil. Consumer subjective and objective knowledge, interest in health-related issues, and demographic variables were studied for their potential relationship (explanatory capacity) with olive oil consumption frequency, using a sample of 256 inhabitants of Montevideo (Uruguay). Several of the studied variables were found to relate to olive oil consumption, such as subjective and objective knowledge, age, education level, marital status, and interest in health-related issues. Subjective knowledge was found to have the highest explanatory capacity. An increase in subjective knowledge is therefore expected to lead to an increase in consumption frequency among regular olive oil consumers, while it may also encourage less frequent or non-consumers to purchase olive oil and become acquainted with the product.

关键词： olive oil Subjective Knowledge objective Knowledge Health Consciousness Decision Trees

Is the kafirin profile capable of modulating the ileal digestibility of amino acids in a soybean meal-sorghum diet fed to pigs?

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Animal Nutrition 2019年第2期5卷 124-129页

作者： v.ctor A.Balderrama-Pérez JoséG.Gómez-Soto Tércia C.Reis de Souza Ericka R.Rodríguez Gerardo Mariscal-Landín Facultad de Estudios Superiores Cuatitlán Universidad National Autónoma de MéxicoCuautitlan54714Mexico Facultad de Cientias Naturales Universidad Autónoma de QuerétaroQuerétaro76230Mexico Centro Nacional de Investigación Disciplinaria en Fisiología y Mejoramiento Animal Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasAjuchitilan76380Mexico

The effects of kafirins on protein and amino acid ileal digestibility have not been evaluated in vivo in *** aim of this study was to determine the effects of protein profile on apparent ileal digestibility(AID)of amino acids. We used a sorghum hybrid with low tannin content(vested from 2 different plots with different kafirin profile. Sorghum with greater content of total kafirins had less content of y-and al-kafirins and higher content of β-and a2-kafirins than that with lower content of total kafirins. Two sorghum-soybean meal(SBM) diets were formulated: 1) low kafirin(LK) content(32.2 g/kg) and 2) high kafirin(HK) content(48.1 g/kg). A control diet(maize-SBM) and a reference SBM-diet were also prepared. The reference diet was fed to all pigs following the experimental period and was used to estimate the AID of cereals by the difference method. 'T' cannulas were fixed in the distal ileum of 18 barrows(6 by treatment), divided into 2 groups of 9 pigs. The pigs were fed 2.5 times their maintenance requirement of digestible energy(110 kcal/kg BW00.75). The AID of dry matter,protein, amino acids, and energy of the experimental diets was measured;the AID of cereals(maize, LK sorghum and HK sorghum) was estimated by the difference method. The maize-SBM diet was more digestible than the sorghum-SBM diets, only with respect to valine(P of valine in the maize-SBM diet was higher than that in sorghum-SBM diets. The changes in kafirin profile between the diets only affected the AID of threonine(P ompared with HK diet. Regarding the AID of cereals, maize exhibited greater AID than sorghum, with respect to valine(P omparison of sorghum with LK and HK content showed that the AID of threonine and serine increased by 50.5(P vely. The higher content of γ-kafirins in L

关键词： Amino acids Ileal digestibility Kafirin Pig Sorghum

Sintering study of Ti6Al4v powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： JoséLuis Cabezas-villa JoséLemus-Ruiz Didier Bouvard omar Jiménez Héctor Javier vergara-Hernández Luis olmos University Michoacana of San Nicolás of Hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of San Nicolás of Hidalgo INICITMorelia 58060México

Ti6Al4v powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 v powders.

关键词： Ti6Al4v powders dilatometry microhardness sintering kinetics compression failure behavior

Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state,Mexico:implication for provenance

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Journal of Palaeogeography 2024年第3期13卷 375-400页

作者： Mayank Shukla Sanjeet K.verma Mayla A.Ramos-vázquez John S.Armstrong-Altrin Karla R.Hernández-Martínez Sumit Mishra vivek P.Malviya Héctor Hernández-Mendoza Posgrado de la Division de Geociencias Aplicadas Instituto Potosino de Investigacion Científica y Tecnologica(IPICYT)Camino a la Presa San José2055San Luis Potosí78216Mexico Division de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnologica(IPICYT)Camino a la Presa San Jose 2055San Luis Potosí78216Mexico Universidad Nacional Autonoma de México Instituto de Ciencias del Mar y LimnologíaUnidad de ProcesosOceanicos y CosterosCiudad UniversitariaCiudad de México 04510Mexico Department of Marine Sciences Bharathidasan UniversityTiruchirappalli620024Tamil NaduIndia Instituto de Geociencias Universidad Nacional Autonoma de MéxicoBoulevard Juriquilla 300176230JuriquillaQueretaroMexico Department of Applied Geology Dr.Harisingh Gour Central UniversitySagar470002Madhya PradeshIndia Instituto de Investigacion de Zonas Desérticas Universidad Autònoma de San Luis PotosíAltair 200CP 78377San LuisS.L.P.Mexico Universidad del Centro de Mexico Capitán Caldera 75CP 78250San LuisS.L.P.Mexico

Geochemical and mineralogical studies were performed in the La Pesca(LP)and Tesoro Altamira(TA)beach sediments,located in the Tamaulipas state,northern Gulf of *** main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach *** sediments are composed of quartz with small amounts of accessory minerals such as plagioclase,calcite,orthoclase,microcline,and *** beach sediments are classified as fine-grained and very well sorted,however LP has coarse skewed and leptokurtic sediments,whereas TA has fine-skewed and very leptokurtic *** chemical index of weathering(CIW’)indicates intense weathering in the source *** quartz grain microtextures in the LP and TA are classified into mechanical,chemical,and mechanical/chemical *** features such as fractures,pits,percussion marks,abrasion fatigue,and v-shaped marks favor high-energy littoral,fluvial,subaqueous-marine,and aeolian *** chemical features indicate solution pits and crystalline overgrowth,which suggests a silica saturated marine *** mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine *** and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC),Sierra Madre oriental(SMor)and oaxaquia *** major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico,which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

Contrasting arthropod communities associated with dwarf mistletoes Arceuthobium globosum and A. vaginatum and their host Pinus hartwegii

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Journal of Forestry Research 2018年第5期29卷 1351-1364页

作者： León F.Chávez-Salcedo Mónica E.Queijeiro-Bolanos v.ctor López-Gómez Zenón Cano-Santana Blanca E.Mejía-Recamier Aurea Mojica-Guzmán Laboratorio de Interacciones y Procesos Ecologicos Departamento de Ecología y Recursos Naturales Facultad de Ciencias Universidad Nacional Autonoma de Moico Av.Universidad 3000 04510 Mexico City Mexico Laboratorio de Ecología y Sistemática de Microartr dpodos Departamento de Ecología y Recursos Naturales Facultad de Ciencias Universidad Nacional Autónoma de M4xico Av.Universidad 3000 04510 Mexico City Mexico Instituto de Biologia Universidad Nacional Autdnoma de Mexico Av. Universidad 3000 04510 Mexico City Mexico Departamento de Ecologia Facultad de Ciencias Naturales Universidad Autdnoma de Quer6taro Av.de las Ciencias s/n 76230 Queretaro Queretaro Mexico

Arthropod communities and epiphytic plants associated with tree canopies have been widely studied and have revealed a great diversity of organisms; however,the community hosted by parasitic plants,such as dwarf mistletoes,remains poorly *** the coniferous forests of North America,dwarf mistletoe infection（Arceuthobium spp.） significantly damages the health of the forest,causing large financial losses for the forest industry,but it also positively affects diversity,especially of mammals and *** study examined the attributes of the arthropod communities associated with two species of dwarf mistletoe [Arceuthobium globosum Hawksw.＆ Wiens and ***（Humb.＆ *** Willd.） ***] and their host Pinus hartwegii *** 2010,in five sites located in Zoquiapan（Central Mexico）,we collected plant tissue from the three species *** were separated from the plant tissue and identified to the finest level *** collected 32,059 individuals,for which51 morphospecies were identified,belonging to 15 taxonomic orders; the most abundant orders for the three plants were Prostigmata,Thysanoptera and *** community associated with *** had the highest value of diversity（H＇= 1.47; ***,H＇= 0.64; ***,H＇= 0.68） and species richness（S = 40; ***,S = 30; ***,S = 35）; while abundance was significantly higher for the mistletoes（***,n = 407 individuals/sample; ***,n = 536 individuals/sample; ***,n = 134 individuals/sample）.Species richness,abundance and diversity were significantly different for the three studied plants,as well for sampling month and the interaction of these two factors（except for diversity）.The results suggest that the canopy of *** is an important element in the ecosystem,providing a mosaic of resources and conditions to the associated *** also propose that mistletoes are key species within the forest canopy,as they greatly influence the establishment of d

关键词： Arceuthobium spp Pinus hartwegii Arthropod community Thrips Mites Hemiparasitic plants

Integrated management of natural resources in the Ecuador Highlands

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Agricultural Sciences 2012年第5期3卷 768-779页

作者： v.ctor Hugo Barrera Luis orlando Escudero Jeffrey Alwang Robert Andrade Gordon INIAP Quito Ecuador Institute Department of Agricultural and Applied Economics virginia Polytechnic Institute and State University Blacksburg Virginia USA Institute Department of Agricultural and Applied Economics virginia Polytechnic Institute and State University Blacksburg VirRobert ginia USA

The Andean region of Ecuador is characterized by extreme poverty caused by low agricultural productivity, limited off-farm opportunities, and lack of access to markets. Poverty is related to degradation of natural resources as lagging agricultural productivity leads to incursions into fragile areas and use of erosive farming techniques on steeply sloped hillsides. Food production in fragile areas degrades soil and water resources, contributes to deforestation and loss of biodiversity, and reduces productive potential over time. This article discusses an agricultural development project designed to reduce the long-term downward development spiral in a watershed in Bolivar, Ecuador. The applied research program began with analysis of the state of soil resources, water, and biodiversity in the Chimbo sub-watershed. This information was used to design a plan with the input of local stakeholders to introduce environmentally friendly farming practices, soil and water conservation techniques, and various institutional innovations to promote resource conservation. This adaptive management program has been a solid success. This article describes the project, the challenges it faced, and how the process of adaptive management led to consensus among stakeholders about the appropriateness of sustainable management practices. We show how implementation of enhanced management practices contribute to reduced environmental vulnerability and improved welfare.

关键词： Component Natural Capital Micro-Watershed Systems Approach Adaptive and Integrated Watershed Management

A Model Metabolic Cycle Simulated with the Mathematica Program

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Journal of Biomedical Science and Engineering 2014年第5期7卷 286-295页

作者： v.ctor García-Herrero Francisco López-Cánovas Antonio Sillero Departamento de Bioquímica Facultad de Medicina Instituto de Investigaciones Biomédicas Alberto Sols UAM/CSIC Madrid Spain

A system of differential equations has been used to simulate a model metabolic cycle, containing only one initial substrate and 8 irreversible enzymes. The metabolic course of the intermediates (products/substrates) was also explored in different situations: changes in the kinetic constants of one of the enzymes of the cycle;introduction of one reversible step;consecutive increments in the Km values of each enzyme of the cycle and the presence of two initial substrates. A decrease or an increase in the Km value of one of the enzymes of the cycle promotes a decrease or an increase in the steady state level of its own substrate, respectively;by the contrary, a decrease or an increase in the vmax value promotes, respectively, an increase or a decrease in the stationary level of the corresponding substrate. A comparison between a linear and a cyclic metabolic pathway is also presented.

关键词： Metabolic Pathways Metabolic Cycle Mathematical Simulations Differential Equations

Bioavailability of Chlorpyrifos in Wheat Plants (<i>Triticum aestivun</i>)

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Agricultural Sciences 2014年第8期5卷 660-667页

作者： Sylvia v. Copaja Rosa vergara Héctor R. Bravo Departamento de Química Facultad de Ciencias Universidad de Chile Santiago Chile

Adsorption processes of chlorpyrifos in two Chilean agro soils (Calera: C;San Esteban: SE) in relation with the bioaccumulation in wheat plants (Triticum aestivun) were studied. RP-HPLC method was developed to determine the chlorpyrifos content in soils, roots and seedling tissues. The two soils showed high adsorption capacity (C = 78%, SE = 92%). The values are not in relation with the contents of organic matter (C = 3.9% and SE = 2.0%) and clay (C = 12.7% and SE = 10.1%) determined in the soils. Persistence and mobility of chlorpyrifos in the soils were estimated from halflife values (Csoil = 23 d, SEsoil = 14 d) and the Guss index (Csoil = 0.89, SEsoil = 0.25) respectively. These values are in the range of non-leaching compounds, and suggest that there should be no pollutant in the ground water. Wheat plants grown in both soils incubated with chlorpyrifos bioaccumulate residues in roots and seedling tissues. Root tissues showed the greatest contents (C = 22.3 mg/k. f. wt;SE = 51.8 mg/kg. f. wt.). Germination and growth of wheat young plants were not inhibited for the contents in the tissues. A relation between the levels of chlorpyrifos residues in the soils and the bioaccumulation in wheat tissues was estimated from the BAI parameter. values showed that the bioaccumulation is dependent on the residues contents in soils. These results suggest that bioavailability of chlorpyrifos in wheat plants may be a harmful pollutant for mammals if it remains stable at all growth stage of the plant. Further research should be considered to see if bioavailability in forage and/or grain can occur.

关键词： Soil Chlorpyrifos Wheat Persistence Bioavailability

Depreciation factor equation to evaluate the economic losses from ground failure due to subsidence related to groundwater withdrawal

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Natural Science 2014年第3期6卷 108-113页

作者： v.ctor Manuel Hernández-Madrigal Jesús Arturo Muniz-Jáuregui v.ctor Hugo Garduno-Monroy Netzahualcoyotl Flores-Lázaro Sócrates Figueroa-Miranda Instituto de Investigaciones en Ciencias de La Tierra Universidad Michoacana de San Nicolás de HidalgoMoreliaMéxico Universidad Nacional Autónoma de México MoreliaMéxico

Subsidence due to groundwater withdrawal is a complex hydrogeological process affecting numerous cities settled on top of fluviolacustrine deposits. The discrete spatial variation in the thickness of these deposits, in combination with subsidence due to groundwater withdrawal, generates differential settlements and aseismic ground failure (AGF) characterized by a welldefined scarp. In cities, such AGF causes severe damages to urban infrastructure and considerable economic impact. With the goal of arriving to a general criterion for evaluating the economic losses derived from AGF, in the present work we propose the following equation: ELi = Pvi*DFi. Where Pvi is the value of a property “i”, and DFi is a depreciation factor caused by structural damages of a property “i” due to AGF. The DFi is calculated empirically through: . This last equation is based on the spatial relations of coexistence and proximity of property polygons and the AGF axis. The coexistence is valued as the quotient of the affectation area divided by the total area of the involved property;and the proximity to the AGF axis is expressed as the inverse of the perpendicular distance from the centroid of the property polygon to the AGF axis. The sum of these terms is divided by two to determine the percentage that affects the property value (Pvi). These equations are relevant because it is the first indicator designed for the discrete assessment of the economic impacts due to AGF, and can be applied to real estate infrastructure from either urban or rural areas.

关键词： Aseismic Ground Failure Groundwater Withdrawal Related Subsidence Equation Depreciation Economic Losses

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open Journal of Respiratory Diseases 2012年第2期2卷 17-24页

作者： Manuel Lopez-Meseguer Río Aguilar Carles Bravo v.ctor Monforte Laura Dos Carmen P. Simeon Enric Domingo Antonio Roman Cardiology Department Hospital Universitari de Bellvitge Hospitalet de Llobregat Spain Cardiology Department Hospital Universitari Vall d’Hebron Institut de Recerca del Hospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona Barcelona Spain Department of Physiology Universitat Autonòma de Barcelona Barcelona Spain Internal Medicine Department Hospital Universitari Vall d’Hebron Institut de Recerca del Hospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona Barcelona Spain Respiratory Department Hospital Universitari vall d’Hebron Institut de Recerca del Hospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona Barcelona Spain

Background: Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are serious diseases with similar pathophysiologic aspects. The prognosis of patients with these conditions is highly uncertain, particularly incident cases. Methods: A Cox proportional hazards model was applied to a group of 85 patients (81% women, mean age 52 (18 - 82) years) with PAH (80%) and non-surgical CTEPH (20%) to evaluate risk factors for mortality. The following variables were included in the model: age, etiology, baseline 6-minute walk test (6 mWT), cardiac index, and improvement in the 6 mWT following initiation of first medical treatment. Results: In the multivariate analysis, the response to treatment, assessed by an improvement on the 6 mWT, was the most relevant prognostic factor in these patients (RR, 4.832 (95% CI, 1.888 - 12.364);p = 0.001). The remaining variables studied in this model had less influence on the prognosis: age > 50 years (RR, 0.744 (95% CI, 0.26 - 2.133);p = 0.582);etiology of connective tissue disease-associated PAH (RR, 3.145 (95% CI, 0.995-9.946);p = 0.051) or CTEPH (RR, 0.654 (95% CI, 0.179 - 2.387);p = 0.521) with respect to idiopathic PAH;baseline 6 mWT (RR, 1.173 (95% CI, 0.599 - 4.895);p = 0.315);or cardiac index (RR, 2.295 (95% CI, 0.793 - 6.642);p = 0.125). Conclusions: There is a high degree of uncer-tainty regarding the prognosis of PAH and CTEPH at the start of appropriate treatment. our results support the idea that the initial treatment response is of paramount importance as prognostic factor in these patients.

关键词： Pulmonary Arterial Hypertension Chronic Thromboembolic Pulmonary Hypertension Survival Risk Factors