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From leaf to whole-plant water use efficiency(WUE)in complex canopies:Limitations of leaf WUE as a selection target

The Crop Journal 2015年第3期3卷 220-228页

作者： Hipólito Medrano Magdalena Tomás Sebastià Martorell aume Flexas Esther Hernández Joan Rosselló Alicia Pou josé-mariano escalona josefina Bota Research Group on Plant Biology under Mediterranean Conditions Department of Biology IMEDEA (CSIC-Universitat de les Illes Balears)Carretera de Valldemossa km 7.5 07122 Palma de Mallorca Spain Institute of Life Science Catholic University of Louvain Place de l'Université 1 B-1348 Louvain-la-Neuve Belgium

Plant water use efficiency(WUE) is becoming a key issue in semiarid areas, where crop production relies on the use of large volumes of water. Improving WUE is necessary for securing environmental sustainability of food production in these areas. Given that climate change predictions include increases in temperature and drought in semiarid regions,improving crop WUE is mandatory for global food production. WUE is commonly measured at the leaf level, because portable equipment for measuring leaf gas exchange rates facilitates the simultaneous measurement of photosynthesis and transpiration. However,when those measurements are compared with daily integrals or whole-plant estimates of WUE, the two sometimes do not agree. Scaling up from single-leaf to whole-plant WUE was tested in grapevines in different experiments by comparison of daily integrals of instantaneous water use efficiency [ratio between CO2assimilation(AN) and transpiration(E); AN/E] with midday AN/E measurements, showing a low correlation, being worse with increasing water stress. We sought to evaluate the importance of spatial and temporal variation in carbon and water balances at the leaf and plant levels. The leaf position(governing average light interception) in the canopy showed a marked effect on instantaneous and daily integrals of leaf WUE. Night transpiration and respiration rates were also evaluated, as well as respiration contributions to total carbon balance. Two main components were identified as filling the gap between leaf and whole plant WUE: the large effect of leaf position on daily carbon gain and water loss and the large flux of carbon losses by dark respiration. These results show that WUE evaluation among genotypes or treatments needs to be revised.

关键词： Water use Drought Intrinsic water use efficiency 13C Instantaneous water use efficiency Whole plant water use efficiency

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Processing of Aerosol Particles in Convective Cumulus Clouds:Cases Study in the Mexican East Pacific

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Advances in Atmospheric Sciences 2010年第6期27卷 1331-1343页

作者： josé C.JIMNEZ-escalona Oscar PERALTA ESIME UP Ticomán National Polytechnic Institute Chemistry Faculty National Autonomous University of MexicoCiudad Universitaria

In the Mexican Intertropical Convergence Zone, particle size distributions within 500 m of cloud boundaries at altitudes of 1000, 2500, and 4200 m, were compared against size distributions at the same levels but 1500 m away from the clouds. The differences in the distributions near and far from the cloud are related to processes that may change particle properties inside the cloud. Chemical changes in the aerosols are deduced from the particles＇ refractive index, as derived from comparisons with the scattering coeflcient measured by a nephelometer. An analysis of ten cloud systems indicates that vertical transport of cloud base aerosol followed by entrainment/detrainment is the cloud processing signature most frequently observed in the comparisons （65%）. Changes in the chemical composition are observed in approximately 20% of the cases and another 20% of the cases showed removal by precipitation. About 5% of the comparisons showed clear evidence of changes by coalescence. The principal effect of these cloud-processed aerosols is observed in the increase of optical depth in the layer from 30 m to 4200 m in the near-cloud regions, in comparison with the atmosphere further from clouds.

关键词： cloud processing cloud interaction scattering redistribution entrainment

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NDT-Suite: A Methodological Tool Solution in the Model-Driven Engineering Paradigm

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Journal of Software Engineering and Applications 2014年第4期7卷 206-217页

作者： Julián Alberto García-García María josé escalona Francisco josé Domínguez-Mayo Alberto Salido Web Engineering and Early Testing Research Group University of Seville Seville Spain

Although the Model-Driven paradigm is being accepted in the research environment as a very useful and powerful option for effective software development, its real application in the enterprise context is still a challenge for software engineering. Several causes can be stacked out, but one of them can be the lack of tool support for the efficient application of this paradigm. This paper presents a set of tools, grouped in a suite named NDT-Suite, which under the Model-Driven paradigm offer a suitable solution for software development. These tools explore different options that this paradigm can improve such as, development, quality assurance or requirement treatment. Besides, this paper analyses how they are being successfully applied in the industry.

关键词： Model-Driven Web Engineering Model-Based Suite Tools Practical Experiences NDT NDT-Suite

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A Metamodel for Agile Requirements Engineering

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Journal of Computer and Communications 2019年第2期7卷 1-22页

作者： Eva-Maria Schon Jorge Sedeno Manuel Mejías Jorg Thomaschewski María josé escalona Department of Computer Languages and Systems University of SevilleSevilleSpain Faculty of Technology University of Applied Sciences Emden/LeerEmdenGermany

Value delivery is becoming an important asset for an organization due to increasing competition in industry. Therefore, companies apply Agile Software Development (ASD) to be more competitive and reduce time to market. Using ASD for the development of systems implies that established approaches of Requirements Engineering (RE) undergo some changes in order to be more flexible to changing requirements. To this end, the field of agile RE is emergent and different process models for agile RE have arisen. The aim of this paper is to build an abstract layer about the variety of existing process models by means of a metamodel for agile RE. It has been created in several iterations and relies on the evaluation of related process models. Furthermore, we have derived process models for agile RE in industry by presenting instances of the metamodel in two different cases: one is based on Scrum whereas the other is based on Kanban. This paper contributes to the software development body of knowledge by delivering a metamodel for agile RE that supports researchers and practitioners modeling and improving their own process models. We can conclude that the agile RE metamodel is highly relevant for the industry as well as for the research community, since we have derived it following empirical research in the field of ASD.

关键词： Agile Software Development Requirements Engineering Human-Centered Design Metamodel

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