743 research outputs found
Distribution of leaf photosynthesis and transpiration within grapevine canopies under different drought conditions
The effects of seasonal drought on the distribution of leaf area, photosynthesis and transpiration within the canopy were evaluated for two Spanish grapevine cultivars. Both varieties were cultivated according to their typical training system.At early stages of drought, reduction of photosynthesis and transpiration was only observed in sun-exposed leaves. As drought intensified, even less sun-exposed leaves were affected. Severe drought reduced photosynthesis and transpiration in all locations of the canopy except for most shaded leaves in the inner part. However, those leaves were almost unproductive, and seemed to be insensitive to variation of both light intensity and drought. Leaf area was also reduced by drought, but the distribution of these reductions within the canopy differed between cultivars, possibly reflecting differences in the training system.Leaves from all locations of the canopy except those in the central part showed a similar radiation use efficiency, suggesting that the observed variation in photosynthesis within the canopy was mostly related to different light interception, while other factors such as different leaf age should play only a minor role. Photosynthetic radiation use efficiency strongly depended on both, pre-dawn leaf water potential and light-saturated stomatal conductance. The interest of these results for modeling purposes is discussed.
Modern viticulture in southern Europe: Vulnerabilities and strategies for adaptation to water scarcity
Water
is
now
considered
the
most
important
but
vulnerable
resource
in
the
Mediterranean
region.
Nev
ertheless,
irrigation
expanded
fast
in
the
region
(e.g.
South
Portugal
and
Spain)
to
mitigate
environmental
stress
and
to
guarantee
stable
grape
yield
and
quality.
Sustainable
wine
production
depends
on
sustain
able
water
use
in
the
wine’s
supply
chain,
from
the
vine
to
the
bottle.
Better
understanding
of
grapevine
stress
physiology
(e.g.
water
relations,
temperature
regulation,
water
use
efficiency),
more
robust
crop
monitoring/phenotyping
and
implementation
of
best
water
management
practices
will
help
to
mitigate
climate
effects
and
will
enable
significant
water
savings
in
the
vineyard
and
winery.
In
this
paper,
we
focused
on
the
major
vulnerabilities
and
opportunities
of
South
European
Mediterranean
viticulture
(e.g.
in
Portugal
and
Spain)
and
present
a
multi-level
strategy
(from
plant
to
the
consumer)
to
overcome
region’s
weaknesses
and
support
strategies
for
adaptation
to
water
scarcity,
promote
sustainable
water
use
and
minimize
the
environmental
impact
of
the
sector
Chaos in Small-World Networks
A nonlinear small-world network model has been presented to investigate the
effect of nonlinear interaction and time delay on the dynamic properties of
small-world networks. Both numerical simulations and analytical analysis for
networks with time delay and nonlinear interaction show chaotic features in the
system response when nonlinear interaction is strong enough or the length scale
is large enough. In addition, the small-world system may behave very
differently on different scales. Time-delay parameter also has a very strong
effect on properties such as the critical length and response time of
small-world networks
The physiology of ex vitro pineapple ( Ananas comosus L. Merr. var MD-2) as CAM or C3 is regulated by environmental conditions: proteomic and transcriptomic profiles
Pineapple is one of the most important tropical crops worldwide. The use of Temporary Immersion Bioreactors (TIB) for the first stages of pineapple propagation enables precise control of plant growth, increases the rate of plant multiplication, decreases space, energy and labor requirements for pineapple plants in commercial micropropagation. Once the plantlets are ready to be taken from the reactors, they are carefully acclimatized to adapt to natural environmental conditions, and a facultative C3/CAM metabolism in the first two months of growth is characteristic of pineapple plants, depending on environmental conditions. We subjected two sets of micropropagated pineapple plants to C3 and CAM-inducing environmental conditions, determined by light intensity/relative humidity (respectively 40μmol.m-2s-1/85% and 260μmol.m-2.s-1/50%). Leaves of pineapple plants grown under CAM inducing conditions showed higher leaf thickness and more developed cuticles and hypodermic tissue. Proteomic profiles of several proteins, isoenzyme patterns and transcriptomic profiles were also measured. Five major spots were isolated and identified, two of them for the first time in Ananas comosus (OEE 1; OEE 2) and the other three corresponding to small fragments of the large subunit of Rubisco (LSU). PEPC and PEPCK were also detected by immunobloting of 2DE at the end of both ex vitro treatments (C3/CAM) during the dark period. Isoenzymes of SOD and CAT were identified by electrophoresis and the transcript levels of OEE 1 and CAT were associated with CAM metabolism in pineapple plants
Applying Model-Driven Paradigm for the Improvement of Web Requirement Validation
This paper proposes an approach for Web requirements validation by applying
the model-driven paradigm in classical requirements validation techniques. In particular,
we present how the Navigational Development Techniques (NDT) approach exploits the
model-driven paradigm to improve its requirements validation task by exploring tool cases
that systematize or even automate the application of requirements validation techniques.
Our solution is validated by applying it in a real industrial environment. The results and
the learned lessons are presented accordingly
Vortices and domain walls in a Chern-Simons theory with magnetic moment interaction
We study the structure and properties of vortices in a recently proposed
Abelian Maxwell-Chern-Simons model in dimensions. The model which is
described by gauge field interacting with a complex scalar field, includes two
parity and time violating terms: the Chern-Simons and the anomalous magnetic
terms. Self-dual relativistic vortices are discussed in detail. We also find
one dimensional soliton solutions of the domain wall type. The vortices are
correctly described by the domain wall solutions in the large flux limit.Comment: To be published in Phys RevD 23 pages, RevTex, 5 figure
Detecting web requirements conflicts and inconsistencies under a model-based perspective
Web requirements engineering is an essential phase in the software project life cycle for the project results. This phase covers different activities and tasks that in many situations, depending on the analyst’s experience or intuition, help getting accurate specifications. One of these tasks is the conciliation of requirements in projects with different groups of users. This article presents an approach for the systematic conciliation of requirements in big projects dealing with a model-based approach. The article presents a possible implementation of the approach in the context of the NDT (Navigational Development Techniques) Methodology and shows the empirical evaluation in a real project by analysing the improvements obtained with our approach. The paper presents interesting results that demonstrate that we can get a reduction in the time required to find conflicts between requirements, which implies a reduction in the global development costs.Laboratorio de Investigación y Formación en Informática Avanzad
Detecting web requirements conflicts and inconsistencies under a model-based perspective
Web requirements engineering is an essential phase in the software project life cycle for the project results. This phase covers different activities and tasks that in many situations, depending on the analyst’s experience or intuition, help getting accurate specifications. One of these tasks is the conciliation of requirements in projects with different groups of users. This article presents an approach for the systematic conciliation of requirements in big projects dealing with a model-based approach. The article presents a possible implementation of the approach in the context of the NDT (Navigational Development Techniques) Methodology and shows the empirical evaluation in a real project by analysing the improvements obtained with our approach. The paper presents interesting results that demonstrate that we can get a reduction in the time required to find conflicts between requirements, which implies a reduction in the global development costs.Laboratorio de Investigación y Formación en Informática Avanzad
CERVANTES: A Model-Based Approach for Service-Oriented Systems Development
Context: The benefits of the Model-Driven Software Engineering application for Service-Oriented Computing. Objective: This paper proposes a Model-Based approach for Service-Oriented Systems Development. Method: Following the Model-Driven Reverse Engineering process, from the models discovery, to the generation of the current Model-Based Approach for Service-Oriented Systems Development. Results: The CERVANTES metamodel is presented and compared to other initiatives. Conclusions: This study shows how Model-Driven Engineering can be used to develop Service Oriented Systems in practice
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