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Modelling the impacts of cover crop management strategies on the water use,carbon exchange and yield of olive orchards

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journal of Forestry Research 2023年第1期34卷 283-295页

作者： Alvaro López-Bernal Omar García-Tejera Luca Testi Francisco J.Villalobos Departamento de Agronomía Universidad de CórdobaCampus de RabanalesEdifi cio C414071 CórdobaSpain Departamento de Ingeniería Agraria Y del Medio Natural Universidad de La LagunaCarretera General de Geneto 238200 San Cristóbal de La LagunaSpain Instituto de Agricultura Sostenible(IAS) Consejo Superior de Investigaciones Científi cas(CSIC)Av.Menéndez Pidal S/N14080 CórdobaSpain

Cover crops have long been proposed as an alternative soil management for minimizing erosion rates in olive stands while providing additional ecosystem services.However,the trade-off between these benefits and the competition for water with the trees makes the definition of optimal management practices a challenging task in semiarid climates.This work presents an improved version of OliveCan,a process-based simulation model of olive orchards that now can simulate the main impacts of cover crops on the water and carbon balances of olive orchards.Albeit simple in its formulation,the new model components were developed to deal with different cover crop management strategies.Examples are presented for simulation runs of a traditional olive orchard in the conditions of southern Spain,evaluating the effects of different widths for the strip occupied by the cover crop(Fcc)and two contrasting mowing dates.Results revealed that high Fccresulted in lower olive yields,but only when mowing was applied at the end of spring.In this regard,late mowing and high Fccwas associated with lower soil water content from spring to summer,coinciding with olive flowering and the earlier stages of fruit growth.Fccwas also negatively correlated with surface runoff irrespective of the mowing date.On the other hand,net ecosystem productivity(NEP)was substantially affected by both Fccand mowing date.Further simulations under future climate scenarios comparing the same management alternatives are also presented,showing substantial yield reductions by the end of the century and minor or negligible changes in NEP and seasonal runoff.

关键词： Carbon exchange Cover crops Crop modelling Evapotranspiration Olea europaea L

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Metabolic enzymes in seasonally acclimatized and cold acclimated rufous-collared sparrow inhabiting a Chilean Mediterranean environment

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Current Zoology 2014年第3期60卷 338-350页

作者： Isaac PENA-villalobos Monica NUNEZ-VILLEGAS francisco BOZINOVIC Pablo SABAT Departamento de Ciencias Ecologicas Facultad de Ciencias Universidad de Chile Casilla 653 Santiago Chile Departamento de Ecologia and Center of Applied Ecology & Sustainability (CAPES) Facultad de Ciencias Biol6gicas Pontificia Universidad Cat61ica de Chile Santiago 6513677 Chile

Due to the higher energy requirements of birds during winter, it is predicted that the activities of metabolic enzymes (e.g., citrate synthase, CS and cytochrome C oxidase, COX) should increase in tandem with increases in rates of energy expenditure (e.g., basal metabolic rate, BMR). However, there is mixed support for the hypothesis of enzymatic acclimatization. Furthermore, there is little information about the effect of ambient temperature on energetics and tissue enzyme activity levels in passerines inhabiting seasonal Mediterranean environments. In this study we evaluated the interplay between BMR and enzyme activities of freshly caught individuals of the passerineZonotrichia capensisin winter and summer in a Mediterranean environment from central Chile, and also in warm (30°C) and cold (15°C) lab-acclimated birds. The results revealed a lack of seasonal variation in BMR, thermal conductance and in the activity of CS and COX. However, we found higher BMR and lower thermal conductance in cold-acclimated than in warm-acclimated birds. Also, total CS activity was higher in the flight muscles of cold-acclimated than in warm-acclimated birds. We found also a significant correlation between BMR and total CS activity in pectoral muscle. Although some authors have suggested that BMR mainly depends on the metabolic intensity and mass of internal organs, our results revealed that skeletal muscles such as the flight muscles may also affect BMR. Finally, differences in the acclimation and acclimatization responses in Rufous-collared sparrows suggest that large-scale oscillations in the physical environment might maintain the capacity for flexibility in thermogenic traits through generations.

关键词：环境温度代谢酶地中海冷驯化智利栖息麻雀季节性

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Gas Separation Membranes with Atom-Thick Nanopores:The Potential of Nanoporous Single-Layer Graphene

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Accounts of Materials Research 2022年第10期3卷 1073-1087页

作者： Luis francisco villalobos Deepu j.Babu Kuang-jung Hsu Cedric Van Goethem Kumar Varoon Agrawal Laboratory of Advanced Separations École Polytechnique Fédérale de LausanneSion 1950Switzerland Department of Materials Science and Metallurgical Engineering Indian Institute of TechnologyHyderabadTelangana 502284India

CONSPECTUS:Gas separation is one of the most important industrial processes and is poised to take a larger role in the transition to renewable energy,e.g.,carbon capture and hydrogen purification.Conventional gas separation processes involving cryogenic distillation,solvents,and sorbents are energy intensive,and as a result,the energy footprint of gas separations in the chemical industry is extraordinarily high.This has motivated fundamental research toward the development of novel materials for highperformance membranes to improve the energy efficiency of gas separation.

关键词： separation distillation energy

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Body Image Anxiety on University Students (Differences between Men and Women)

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Open journal of Medical Psychology 2014年第5期3卷 348-354页

作者： Humberto Blanco Vega juan francisco Aguirre Chávez judith Margarita Rodríguez-villalobos josé René Blanco Ornelas Héctor Luis Medina López Faculty of Physical Culture Sciences Autonomous University of Chihuahua Chihuahua México

The aim of this research lies on comparing anxiety body image profiles between male and female university students. A total sample of 2089 freshmen—902 women and 1187 men is from the different degrees offered by the Autonomous University of Chihuahua, with an average age of 18.23 ± 0.74 years. The approach used in the research is part of a quantitative design with a survey description. The differences found between men and women regarding their own perception of anxiety suggest that when designing any kind of intervention that aims at the decreasingly perceived anxiety, the gender variable will have to be taken into account. Future investigations should respond to these discoveries in larger samples.

关键词： Students’ Beliefs Gender Differences Higher Education Academic Performance Students’ Characteristics

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Discharge Coefficient Measurements Using Heron's Fountain

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journal of Civil Engineering and Architecture 2019年第3期13卷 195-203页

作者： Gevo Abcarian Zainab Algharib Omran Hussain Ana Martin Abraham Villa francisco villalobos Tadeh Zirakian David Boyajian Department of Civil Engineering and Construction Management California State UniversityNorthridgeCA 91330USA

Civil Engineering design students at CSUN (California State University, Northridge), aimed to demonstrate the pneumatic action of liquid water as it flows through an airtight one-way vessel system which is known as Heron’s Fountain. This project explores hydraulic and pneumatics principles commonly found in environment control systems, such as the non-isothermal heating facilities located on the CSUN campus. Since this was a simply constructed version of an ancient Greek fountain, its development required the collaboration of the team to execute its simple function. The parameters involved were diameter, length, height, and density. This analysis utilizes Pascal and Bernoulli’s equations to reinforce the principles of fluid mechanics. The fountain action is described based on flow rate and head loss is described by Darcy’s equation. Friction loss with an angled fitting attached to the fountain head is described by Reynold’s equation. The experiment observed the performances of two types of reentrant tube fittings for head loss: straight and angled. The experiment enhanced the educational experience of the research team by bringing together creative ideas from different educational and cultural backgrounds. The results of the experiment concluded with a 0.58% error for the straight fitting and 5.3% error for an angled fitting.

关键词： Heron's Fountain hydraulic principles air pressure pneumatics friction factor engineering education

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Quantitative and Qualitative Analysis of Groundwater in Aguanaval and Chupaderos Aquifers （Mexico）

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journal of Earth Science and Engineering 2013年第7期3卷 425-436页

作者： Hugo Enrique jfinez-Ferreira francisco Mojarro Daivila Carlos Bautista-Capetillo Angel villalobos de Alba jean Steiner jose R.Avila Carrasco Department of Applied Engineering Autonomous University of Zacatecas Zacatecas 98000 Mexico USDA(United States Department of Agriculture)-ARS(Agricultural Research Service)-Grazinglands Research Laboratory El Reno 73036 USA

Adequate regional groundwater assessment studies are essential for the correct groundwater management by policy/decision makers; increased use of groundwater resources and drought have led to concern about the future availability of groundwater to meet domestic, agricultural, industrial, and environmental needs. Deep understanding of spatial and temporal water table dynamics together with transport processes is required. This paper gathers historical geological, hidrological and chemical information for quantitative and qualitative as well as spatial and temporal evolution of groundwater for Aguanaval and Chupaderos aquifers, both surrounding Calera aquifer in Mexico. Historical databases were employed to determine temporal trends of water levels and values were projected for years 2010, 2030 and 2050. Potential recharge sites were also identified through water level-topography correlation. The water quality analysis was completed by obtaining, through geostatistics, spatial distributions for bicarbonate, chloride, sulfate, total dissolved solids, temperature, and sodium, employing databases generated in recent sampling campaigns. This analysis provided additional elements to help understand the functioning of groundwater in studied aquifers. Finally, results were compared with permissible values established in the Mexican norm.

关键词：地下水管理含水层墨西哥地下水位动态历史数据库空间分布地下水评价地下水资源

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Genetic Diversity Analysis of jatropha Species from Costa Rica Using AFLP Markers

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American journal of Plant Sciences 2015年第14期6卷 2426-2438页

作者： Roberto Avendano Elmer García Díaz Marta Valdez-Melara Nefertiti Chaves Solano Aníbal Mora villalobos francisco Aguilar Cascante Bruce Williamson Benavides Laura Y.Solís-Ramos Center for Biotechnological Innovations(CENIBiot) CeNAT-CONARESan JoséCosta Rica School of Biology University of Costa RicaSan JoséCosta Rica

The genetic diversity from species of the genus jatropha collected from Costa Rica was analyzed by AFLP (amplified fragments length polymorphism). The study consisted of 114 accessions from 15 populations of 4 different species: j. curcas, j. costaricensis, j. gossypifolia and j. stevensii. These were collected from different locations in Costa Rica. Three different primers were used, resulting in 428 loci, and they were classified in three categories: unique and double bands (UBD), rare bands (RB) and shared bands (SB). The UBD were excluded for a total of 339 polymorphic loci used for the UPGMA dendrogram and principal component analysis (PCA). The species that obtained the highest average of polymorphic loci was j. curcas, which obtained the highest percentage of polymorphic loci (80.24%), followed by j. gossypifolia (79.35%), j. costaricensis (78.76%), and finally j. stevensii (40.71%). The average for the polymorphic loci was of 69.76%. Thus, the phylogeny of the jatropha species in Costa Rica was elucidated, showing j. curcas more related to j. stevensii and this one with j. costaricensis, and j. gossypifolia as the most distant member of the genus. For the best of our knowledge this is the first report of a genetic analysis of j. costaricensis and j. stevensii. The obtained molecular evidence showed high levels of polymorphisms in the present study compared with reports from Africa, India, and China. The molecular diversity estimated in our analysis, together with agronomical or morphological data, can be very useful for plant breeding programs, given the importance of jatropha species in oil production. Interestingly, Central American jatropha material can be used to increase the genetic base of j. curcas populations localized in Asia and Africa, where reduced genetic diversity has been reported.

关键词： jatropha spp. AFLP Molecular Markers Polymorphism Genetic Diversity

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Non-Linear Analysis of Energy Absorption Systems under Impact Loads through FEM

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journal of Mechanics Engineering and Automation 2012年第8期2卷 487-494页

作者： Elias Rigoberto Ledesma-Orozco jose Angel Diosdado-De la Pena Gerardo Israel Pdrez-Soto Alonso Salazar-Garibay juan francisco Reveles-Arredondo Gilberto villalobos-Llamas Pedro Duran-Resendiz Department of Mechanical Engineering Universidad de Guanajuato (DICIS) Salamanca M~xico

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