274 research outputs found
A Value-Driven Framework for Software Architecture
Software that is not aligned with the business values of the organization for which it
was developed does not entirely fulfill its raison d’etre. Business values represent what
is important in a company, or organization, and should influence the overall software
system behavior, contributing to the overall success of the organization. However, approaches
to derive a software architecture considering the business values exchanged
between an organization and its market players are lacking. Our quest is to address this
problem and investigate how to derive value-centered architectural models systematically.
We used the Technology Research method to address this PhD research question.
This methodological approach proposes three steps: problem analysis, innovation, and
validation. The problem analysis was performed using systematic studies of the literature
to obtain full coverage on the main themes of this work, particularly, business value
modeling, software architecture methods, and software architecture derivation methods.
Next, the innovation step was accomplished by creating a framework for the derivation
of a software reference architecture model considering an organization’s business values.
The resulting framework is composed of three core modules: Business Value Modeling,
Agile Reference Architecture Modeling, and Goal-Driven SOA Architecture Modeling.
While the Business value modeling module focuses on building a stakeholder-centric
business specification, the Agile Reference Architecture Modeling and the Goal-Driven
SOA Architecture Modeling modules concentrate on generating a software reference architecture
aligned with the business value specification. Finally, the validation part of
our framework is achieved through proof-of-concept prototypes for three new domain
specific languages, case studies, and quasi-experiments, including a family of controlled
experiments. The findings from our research show that the complexity and lack of rigor
in the existing approaches to represent business values can be addressed by an early requirements
specification method that represents the value exchanges of a business. Also,
by using sophisticated model-driven engineering techniques (e.g., metamodels, model
transformations, and model transformation languages), it was possible to obtain source
generators to derive a software architecture model based on early requirements value
models, while assuring traceability throughout the architectural derivation process. In conclusion, despite using sophisticated techniques, the derivation process of a software
reference architecture is helped by simple to use methods supported by black box
transformations and guidelines that facilitate the activities for the less experienced software
architects. The experimental validation process used confirmed that our framework
is feasible and perceived as easy to use and useful, also indicating that the participants
of the experiments intend to use it in the future
Radical Scavenger Capacity of Jabuticaba Fruit ( Myrciaria cauliflora
Jabuticaba is an exotic fruit native to Brazil that has been arousing medicinal interest. Using chemical (HPLC-PDA, resonance mass spectra, and NMR), electroanalytical (differential pulse voltammetry, radical scavenging assay), and pharmacological (in vivo and in vitro) approaches, we have identified its bioactive compounds and hypotensive effects on hypertensive rats. The hydroalcoholic extract of jabuticaba (HEJ) presents a great quantity of phenolic compounds, and several molecules with hydroxyl groups present high efficiency as an antioxidant. The treatment with HEJ (100 and 300 mg/kg/day, for four weeks) presented hypotensive effects on L-NAME-induced hypertensive rats, possibly improving the nitric oxide bioavailability because of its high antioxidant potential. Furthermore, renal and cardiac hypertrophies were also attenuated after the HEJ treatment. Moreover, the vascular responses to contractile and dilating agonists were improved with the HEJ treatment, which is also able to induce nitric oxide production in endothelial cells
Resource availability and disturbance shape maximum tree height across the Amazon
Tall trees are key drivers of ecosystem processes in tropical forest, but the controls on the distribution of the very tallest trees remain poorly understood. The recent discovery of grove of giant trees over 80 meters tall in the Amazon forest requires a reevaluation of current thinking. We used high-resolution airborne laser surveys to measure canopy height across 282,750 ha of old-growth and second-growth forests randomly sampling the entire Brazilian Amazon. We investigated how resources and disturbances shape the maximum height distribution across the Brazilian Amazon through the relations between the occurrence of giant trees and environmental factors. Common drivers of height development are fundamentally different from those influencing the occurrence of giant trees. We found that changes in wind and light availability drive giant tree distribution as much as precipitation and temperature, together shaping the forest structure of the Brazilian Amazon. The location of giant trees should be carefully considered by policymakers when identifying important hot spots for the conservation of biodiversity in the Amazon.Peer reviewe
Resource availability and disturbance shape maximum tree height across the Amazon
Tall trees are key drivers of ecosystem processes in tropical forest, but the controls on the distribution of the very tallest trees remain poorly understood. The recent discovery of grove of giant trees over 80 meters tall in the Amazon forest requires a reevaluation of current thinking. We used high-resolution airborne laser surveys to measure canopy height across 282,750 ha of old-growth and second-growth forests randomly sampling the entire Brazilian Amazon. We investigated how resources and disturbances shape the maximum height distribution across the Brazilian Amazon through the relations between the occurrence of giant trees and environmental factors. Common drivers of height development are fundamentally different from those influencing the occurrence of giant trees. We found that changes in wind and light availability drive giant tree distribution as much as precipitation and temperature, together shaping the forest structure of the Brazilian Amazon. The location of giant trees should be carefully considered by policymakers when identifying important hot spots for the conservation of biodiversity in the Amazon.Peer reviewe
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