The 3C cooperation model applied to the classical requirement analysis

Aspects related to the users' cooperative work are not considered in the traditional approach of software engineering, since the user is viewed independently of his/her workplace environment or group, with the individual model generalized to the study of collective behavior of all users. This work proposes a process for software requirements to address issues involving cooperative work in information systems that provide distributed coordination in the users' actions and the communication among them occurs indirectly through the data entered while using the software. To achieve this goal, this research uses ergonomics, the 3C cooperation model, awareness and software engineering concepts. Action-research is used as a research methodology applied in three cycles during the development of a corporate workflow system in a technological research company. This article discusses the third cycle, which corresponds to the process that deals with the refinement of the cooperative work requirements with the software in actual use in the workplace, where the inclusion of a computer system changes the users' workplace, from the face to face interaction to the interaction mediated by the software. The results showed that the highest degree of users' awareness about their activities and other system users contribute to a decrease in their errors and in the inappropriate use of the system.

Riverbed: A Novel User-Steered Image Segmentation Method Based on Optimum Boundary Tracking

This paper presents an optimum user-steered boundary tracking approach for image segmentation, which simulates the behavior of water flowing through a riverbed. The riverbed approach was devised using the image foresting transform with a never-exploited connectivity function. We analyze its properties in the derived image graphs and discuss its theoretical relation with other popular methods such as live wire and graph cuts. Several experiments show that riverbed can significantly reduce the number of user interactions (anchor points), as compared to live wire for objects with complex shapes. This paper also includes a discussion about how to combine different methods in order to take advantage of their complementary strengths.

Disulfide Biochemistry in 2-Cys Peroxiredoxin: Requirement of Glu50 and Arg146 for the Reduction of Yeast Tsa1 by Thioredoxin

2-Cys peroxiredoxin (Prx) enzymes are ubiquitously distributed peroxidases that make use of a peroxidatic cysteine (Cys(P)) to decompose hydroperoxides. A disulfide bond is generated as a consequence of the partial unfolding of the alpha-helix that contains Cys(P). Therefore, during its catalytic cycle, 2-Cys Prx alternates between two states, locally unfolded and fully folded. Tsa1 (thiol-specific antioxidant protein 1 from yeast) is by far the most abundant Cys-based peroxidase in Saccharomyces cerevisiae. In this work, we present the crystallographic structure at 2.8 angstrom resolution of Tsa1(C47S) in the decameric form [(alpha(2))(5)] with a DTT molecule bound to the active site, representing one of the few available reports of a 2-Cys Prx (AhpC-Prx1 subfamily) (AhpC, alkyl hydroperoxide reductase subunit C) structure that incorporates a ligand. The analysis of the Tsa1(C47S) structure indicated that G1u50 and Arg146 participate in the stabilization of the Cys(P) alpha-helix. As a consequence, we raised the hypothesis that G1u50 and Arg146 might be relevant to the Cys(P) reactivity. Therefore, Tsa1(E50A) and Tsa1(R146Q) mutants were generated and were still able to decompose hydrogen peroxide, presenting a second-order rate constant in the range of 10(6) M-1 S-1. Remarkably, although Tsa1(E50A) and Tsa1(R146Q) were efficiently reduced by the low-molecular-weight reductant DTT, these mutants displayed only marginal thioredoxin (Trx)-dependent peroxidase activity, indicating that G1u50 and Arg146 are important for the Tsa1-Trx interaction. These results may impact the comprehension of downstream events of signaling pathways that are triggered by the oxidation of critical Cys residues, such as Trx. (C) 2012 Elsevier Ltd. All rights reserved.

Comparison of multiple-input single-output single-user ultra-wideband systems with pre-distortion

This paper presents a performance analysis of a baseband multiple-input single-output ultra-wideband system over scenarios CM1 and CM3 of the IEEE 802.15.3a channel model, incorporating four different schemes of pre-distortion: time reversal, zero-forcing pre-equaliser, constrained least squares pre-equaliser, and minimum mean square error pre-equaliser. For the third case, a simple solution based on the steepest-descent (gradient) algorithm is adopted and compared with theoretical results. The channel estimations at the transmitter are assumed to be truncated and noisy. Results show that the constrained least squares algorithm has a good trade-off between intersymbol interference reduction and signal-to-noise ratio preservation, providing a performance comparable to the minimum mean square error method but with lower computational complexity. Copyright (C) 2011 John Wiley & Sons, Ltd.

Towards a hybrid approach for adapting web graphical user interfaces to heterogeneous devices using context

Ubiquitous Computing promises seamless access to a wide range of applications and Internet based services from anywhere, at anytime, and using any device. In this scenario, new challenges for the practice of software development arise: Applications and services must keep a coherent behavior, a proper appearance, and must adapt to a plenty of contextual usage requirements and hardware aspects. Especially, due to its interactive nature, the interface content of Web applications must adapt to a large diversity of devices and contexts. In order to overcome such obstacles, this work introduces an innovative methodology for content adaptation of Web 2.0 interfaces. The basis of our work is to combine static adaption - the implementation of static Web interfaces; and dynamic adaptation - the alteration, during execution time, of static interfaces so as for adapting to different contexts of use. In hybrid fashion, our methodology benefits from the advantages of both adaptation strategies - static and dynamic. In this line, we designed and implemented UbiCon, a framework over which we tested our concepts through a case study and through a development experiment. Our results show that the hybrid methodology over UbiCon leads to broader and more accessible interfaces, and to faster and less costly software development. We believe that the UbiCon hybrid methodology can foster more efficient and accurate interface engineering in the industry and in the academy.

GEDI: a user-friendly toolbox for analysis of large-scale gene expression data

Abstract Background Several mathematical and statistical methods have been proposed in the last few years to analyze microarray data. Most of those methods involve complicated formulas, and software implementations that require advanced computer programming skills. Researchers from other areas may experience difficulties when they attempting to use those methods in their research. Here we present an user-friendly toolbox which allows large-scale gene expression analysis to be carried out by biomedical researchers with limited programming skills. Results Here, we introduce an user-friendly toolbox called GEDI (Gene Expression Data Interpreter), an extensible, open-source, and freely-available tool that we believe will be useful to a wide range of laboratories, and to researchers with no background in Mathematics and Computer Science, allowing them to analyze their own data by applying both classical and advanced approaches developed and recently published by Fujita et al. Conclusion GEDI is an integrated user-friendly viewer that combines the state of the art SVR, DVAR and SVAR algorithms, previously developed by us. It facilitates the application of SVR, DVAR and SVAR, further than the mathematical formulas present in the corresponding publications, and allows one to better understand the results by means of available visualizations. Both running the statistical methods and visualizing the results are carried out within the graphical user interface, rendering these algorithms accessible to the broad community of researchers in Molecular Biology.

Accessibility and demand at an Emergency Care Unit: the user's perspective

AIM: To analyze the search for Emergency Care (EC) in the Western Health District of Ribeirão Preto (São Paulo), in order to identify the reasons why users turn to these services in situations that are not characterized as urgencies and emergencies. METHODS: A qualitative and descriptive study was undertaken. A guiding script was applied to 23 EC users, addressing questions related to health service accessibility and welcoming, problem solving, reason to visit the EC and care comprehensiveness. RESULTS: The subjects reported that, at the Primary Health Care services, receiving care and scheduling consultations took a long time and that the opening hours of these services coincide with their work hours. At the EC service, access to technologies and medicines was easier. CONCLUSION: Primary health care services have been unable to turn into the entry door to the health system, being replaced by emergency services, putting a significant strain on these services' capacity.

PRoSPer: perceptual similarity queries in medical CBIR systems through user profiles

In this paper, we present a novel approach to perform similarity queries over medical images, maintaining the semantics of a given query posted by the user. Content-based image retrieval systems relying on relevance feedback techniques usually request the users to label relevant/irrelevant images. Thus, we present a highly effective strategy to survey user profiles, taking advantage of such labeling to implicitly gather the user perceptual similarity. The profiles maintain the settings desired for each user, allowing tuning of the similarity assessment, which encompasses the dynamic change of the distance function employed through an interactive process. Experiments on medical images show that the method is effective and can improve the decision making process during analysis.