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The understanding of the mechanical fixation behavior of coatings is crucial for a better comprehension of the bonding systems, especially at the interface between the mortar and the substrate. Physical adherence is related, among other things, to the contents of the materials used in the roughcast and mortar coatings, due to the colloidal water penetration into the pores of the substrate. This work evaluated the influence of different lime solution additions replacing the kneading water in the preparation of roughcast and mortar coatings. Two types of substrates were investigated:ceramic bricks and concrete blocks. Three wall masonry panels were constructed, with dimensions of 220 × 180 cm2, one of concrete block and two of ceramic bricks, followed by the application of roughcast and mortar coating with an average thickness of 5 mm and 20 mm, respectively. Direct tensile bond strength tests were performed and the results, with a 95% confidence level, showed that substrate ceramic and treatment in the roughcast exhibited a better behavior regarding the distribution of the tensile bond strength of the tested specimens. However, no significant differences of the amount of addition used (0%, 5%, 10% and 15%) on the tensile bond strength were observed.

Knowledge about misconceptions is an important element of pedagogical content knowledge. The computing education research community collected a large body of research on misconceptions, using a diverse set of definitions and approaches. Inspired by this prior work, we present an actionable definition of misconceptions, focused on the area most commonly studied: programming and programming languages. We then introduce an organizational structure for collections of programming language misconceptions. We study how existing collections fit our organization, and we present a curated inventory of programming language misconceptions that aims to follow our definition and structure. Our inventory goes beyond traditional programming misconception collections. It connects misconceptions to the authoritative specifications of languages, to places they may be triggered in textbooks, to research papers that discuss them, and it provides support for integrating programming language misconceptions into educational platforms.

Social media represents a large part of the content available on the Web. While the accessibility of the UIs of existing social media platforms has been improving, the same cannot be said about the accessibility of the content authored by their users. Specifically, the accessibility of multimedia content that is increasingly available given the ease of access to mobile devices with cameras. User research has revealed that accessible authoring practices are a foreign concept to most social media users, but also that they are motivated to adopt inclusive practices. Our work focuses on promoting awareness to accessible social media authoring practices and in assisting the authoring process. We have prototyped a Google Chrome extension and an Android application that can identify when a Twitter or a Facebook user is authoring content with images and suggests a text alternative for the image. By suggesting the alternative, we raise awareness to the accessible authoring process and make it easier for the user to include it in the tweet or post. Text alternatives may be suggested from different sources: descriptions entered by other users for the same image, analysis of the main concepts present in the image, or text present in the image, for instance. Our prototypes can also provide text alternatives on demand for images on any web page or Android application, not just social media. In this paper, we highlight some of the challenges faced to offer this support in different technological platforms (web and mobile), but also ones that are raised by the domain characteristics (e.g. detecting the same image, supporting different languages) and that can be addressed through AI based technologies.

We present a case study of Truewind, a mid-size IT consulting company whose distribution of employees is significantly more gender-balanced than the norm. Whereas worldwide employment of women in the ICT sector hardly reaches 20%, women make up almost one third of the developers of the main office of this company. We conducted a case study to gain an understanding of which factors are perceived to contribute to such a gender distribution, and how its employees see it as an advantage. A survey revealed that, independently of gender, employees value gender diversity, pointing out advantages on teamwork, organizational climate, and critical thinking. Further, we collected factors that contribute to the retention of women, which in great part refer to organizational climate and work conditions. Up to a quarter of the IT consultants of Truewind have majored in non-ICT fields, changing their career path mostly from other STEM disciplines.

Made available in DSpace on 2019-10-06T15:33:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Instituto Chico Mendes de Conservação da Biodiversidade Universidade Federal de Uberlândia We describe the formation of the chondrocranium and the ossification pattern of the skull of the Black Caiman (Melanosuchus niger (Spix, 1825)). The embryos were cleared and double-stained with Alizarin Red S and Alcian Blue 8GX. Additionally, they were visualized by histological hematoxylin and eosin staining and computed tomography imaging. The chondrocranium of M. niger comprised the nasal capsule, orbitotemporal, and optic–occipital regions. Its development began at stage 9, with the chondrification of the acrochordal cartilage, trabeculae, and mandibular cartilage. The optic capsule was formed in the caudolateral portion of the chondrocranium at stage 13. The basal plate appeared at stage 14, with foramina for the hypoglossal. The chondrocranium was completely formed at stage 16. The first osteogenic events were noted at stage 13, in the bones, maxilla, jugal, postorbital, and pterygoid. The quadratojugal, prefrontal, frontal, and squamosal began their ossification at stage 14. The parietal bone began to ossify only at stage 20. The basisphenoid began at stage 15 and the parasphenoid began at stage 16. The jaw bones ossified between stages 13 and 16. The dermal elements started their ossification prior to the endochondral bones. Instituto de Ciências Biológicas Universidade Federal de Goiânia (UFG), Chácaras Califórnia Faculdade de Medicina Veterinária Universidade Federal de Uberlândia (UFU), Avenida Pará, 1720 – Umuarama Faculdade de Agronomia e Medicina Veterinária Universidade de Brasília (UnB), ICC Sul Campos Universitário Darci Ribeiro – Sul, Brasília, Distrito Federal Instituto de Ciências Biomédicas Universidade Federal de Uberlândia (UFU), Avenida Pará 1720 – Bloco 2B – Sala 2B22, Caixa Postal 592 Instituto de Biociência Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Rua Cristóvão Colombo, 2265 – Jardim Nazareth Instituto de Ciências Biológicas Universidade de Brasília (UnB), UnB 1° andar – Asa Norte, Brasília, Distrito Federal Instituto de Biociência Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Rua Cristóvão Colombo, 2265 – Jardim Nazareth

Programmers spend a considerable time jumping through editing positions in the source code, often requiring the use of the mouse and/or arrow keys to position the cursor at the desired editing position. We developed Javardeye, a prototype code editor for Java integrated with eye tracking technology for controlling the editing cursor. Our implementation is based on a structured editor, leveraging on its particular characteristics, and augmenting it with a secondary - latent cursor - controlled by eye gaze. This paper describes the main design decisions and tradeoffs of our approach. info:eu-repo/semantics/publishedVersion

3D reconstruction is one of the main topics in computer vision and is heavily applied for creating virtual environments. Photogrammetry is a technique for obtaining 3D information by mapping objects and scenarios using only images. However, this process can take a long time when using large datasets. In this paper, a permissive open-source pipeline is proposed focusing on robustness, efficiency, and low execution time in batch processing. The permissive license allows commercial use without the need of keeping the code open. We mixed an enhanced structure from motion algorithm and a recurrent multi-view reconstruction. We also use Point Cloud Library for normal estimation, surface reconstruction, and texture mapping. We compared our results with COLMAP and MVE techniques using the DTU MVS dataset and real-world scenarios with our own datasets. The results showed a decrease of 69.4% on average time (compared to the best result of other techniques), but also demonstrated the need for more images to generate a complete reconstructed model.

Image-based body tracking algorithms are useful in several scenarios, such as avatar animations and gesture interaction for VR applications. In the last few years, the best-ranked solutions presented on the state of the art of body tracking (according to the most popular datasets in the field) are intensively based on Convolutional Neural Networks (CNNs) algorithms and use large datasets for training and validation. Although these solutions achieve high precision scores while evaluated with some of these datasets, there are particular tracking challenges (for example, upside-down cases) that are not well-modeled and, therefore, not correctly tracked. Instead of lurking an all-in-one solution for all cases, we propose HuTrain, a framework for creating datasets quickly and easily. HuTrain comprises a series of steps, including automatic camera calibration, refined human pose estimation, and known dataset formats conversion. We show that, with our system, the user can generate human pose datasets, targeting specific tracking challenges for the desired application context, with no need to annotate human pose instances manually.

Gestural interfaces in virtual reality (VR) expand the design space for user interaction, allowing spatial metaphors with the environment and more natural and immersive experiences. Typically, machine learning approaches recognize gestures with models that rely on a large number of samples for the training phase, which is an obstacle for rapidly prototyping gestural interactions. In this paper, we propose a solution designed for hi-fi prototyping of gestures within a virtual reality environment through a high-level Domain-Specific Language (DSL), as a subset of the natural language. The proposed DSL allows non-programmer users to intuitively describe a broad domain of poses and connect them for compound gestures. Our DSL was designed to be general enough for multiple input classes, such as body tracking, hand tracking, head movement, motion controllers, and buttons. We tested our solution for wands with VR designers and developers. Results showed that the tool gives non-programmers the ability to prototype gestures with ease and refine its recognition within a few minutes.

Through the last decade, the creation of extended reality (XR) solutions has significantly increased due to the advent of cheaper, more advanced, and accessible instruments like smartphones, headsets, platforms, development kits, and engines. For instance, the number of GitHub repositories for XR related projects jumped from 51 in 2010 to over 15,000 in 2020. At the same time, the developer community approaches the creation of XR applications using inherited design processes and methods from past mainstream platforms such as web, mobile, or even product design. Unfortunately, those platforms do not consider the spatial aspects of these applications. In this paper, we present a revisited design process and a toolkit focused on the challenges innate to XR, that aims to help beginners and experienced teams in the creation of applications and interactions in Virtual, Augmented, and Mixed Reality. We also present a compendium of 113 techniques and 118 guidelines and a set of canvases that guides users through the process, preventing them from skipping important tasks and discoveries. At last, we present a pilot case where we accompany a team with developers and designers running our process and using our toolkit for the first time, showing the benefits of a process that strikes specific issues of XR apps.

Test smells are symptoms in the test code that indicate possible design or implementation problems. Their presence, along with their harmfulness, has already been demonstrated by previous researches. However, we do not know to what extent developers acknowledge the presence of test smells and how to refactor existing code to eliminate them in practice. This study aims to assess open-source developers' awareness about the existence of test smells and their refactoring strategies. We conducted a mixed-method study with two parts: (i) a survey with 73 experienced open-source developers to assess their preference and motivation to choose between 10 different smelly test code samples, found in 272 open-source projects, and their refactored versions; and (ii) the submission of 50 pull requests to assess developers' acceptance of the proposed refactorings. As a result, most surveyed developers preferred the refactored proposal for 78% of the investigated test smells, and the pull requests had an average acceptance of 75% among respondents. Additionally, we were able to provide empiric validation for literature-proposed refactoring strategies. This study demonstrates that although not always using the academic terminology, developers acknowledge both the negative impact of test smells presence and most of the literature's proposals for their removal.

Zinc oxide (ZnO) is a very attractive material which has received growing attention in the academic and technological areas. This metal oxide shows several advantageous properties such as facile and inexpensive synthesis, low toxicity, high surface area, and rich surface chemistry. However, the most impressive property of ZnO is the possibility of obtaining ZnO nanoparticles with different morphologies and crystal size by merely changing the synthetic parameters, such as temperature, pH, or the solvent. Thus, the combination of the attractive chemical, optical, and electrical properties of ZnO to the possibility of easily producing ZnO nanoparticles with different sizes and morphologies makes this metal oxide an extremely versatile material. Because of this versatility, ZnO has found several applications, including the development of electronic and optoelectronic devices, energy conversion in solar cells and supercapacitors, sensing and electrochemical sensing, besides several biomedical applications in photodynamic therapy, disease diagnoses, and microbial killing. Therefore, the objective of this chapter is to highlight the main approaches used to achieve the efficient application of ZnO in biomedical, energy conversion, and electrochemical sensing fields.

This study reports a new electrochemical method for tryptamine determination using a paper-based microfluidic device and a thermoplastic electrode (TPE) as an amperometric detector. Tryptamine (Tryp) is a biogenic amine present in drinks and foods. Even though this compound has some beneficial effects on human health, the ingestion of foods with high concentrations of Tryp may be detrimental, which justifies the need for monitoring the Tryp levels. The TPEs were made from 50% carbon black and 50% polycaprolactone and characterized by cyclic voltammetry, demonstrating enhancement in the analytical response compared to other carbon composites. TPEs also showed a better antifouling effect for Tryp compared to conventional glassy carbon electrodes. Once characterized, the electrodes were incorporated into the microfluidic device to determine Tryp in water and cheese samples using amperometry. A linear range was achieved from 10 to 75 μmol L−1 with limits of detection and quantification of 3.2 and 10.5 μmol L−1, respectively. Therefore, this work shows promising findings of the electrochemical determination of Tryp, bringing valuable results regarding the electrochemical properties of thermoplastic composites.

The syntax of a programming language is the textual form - that conforms to a grammar - to express instructions of a programming model. The key idea of structured code editors is to constrain editing to syntactically valid program code, that is, the modifications ensure that the source code always conforms to the grammar. Syntax is considered an entry barrier when learning how to program. In this work we rehash the concept of structured code editors targeting programming education. We present Javardise, a structured editor for a subset of the Java language, and discuss its features in the light of programming pedagogy.

A simple and low-cost continuous-flow (CF) electrochemical paper-based analytical device (ePAD) coupled with thermoplastic electrodes (TPEs) was developed. The fast, continuous flow combined with flow injection analysis was made possible by adding two inlet reservoirs to the same paper-based hollow channel flowing over detection electrodes, terminating in a fan-shaped pumping reservoir. The upstream inlet reservoir was filled with buffer and provided constant flow through the device. Sample injections were performed by adding 2 μL of the sample to the downstream sample inlet. Differences in flow resistance resulted in sample plugs displacing buffer as the solution flowed over the working electrodes. The electrodes were fabricated by mixing carbon black and polycaprolactone (50% w/w). CF-TPE-ePADs were characterized with chronoamperometry using ferrocenylmethyl trimethylammonium as the electrochemical probe. Optimized flow rates and injection volumes gave analysis times roughly an order of magnitude faster than those of previously reported flow injection analysis ePADs. To demonstrate applicability, the CF-TPE-ePADs were used to quantify caffeic acid in three different tea samples. The proposed method had a linear range from 10 to 500 μmol L

A procedure based on liquid–liquid extraction (LLE) and phase separation using magnetically stirred salt-induced high-temperature liquid-liquid extraction (PS-MSSI-HT-LLE) was developed to extract and pre-concentrate ciprofloxacin (CIPRO) and enrofloxacin (ENRO) from animal food samples before electroanalysis. Firstly, simple LLE was used to extract the fluoroquinolones (FQs) from animal food samples, in which dilution was performed to reduce interference effects to below a tolerable threshold. Then, adapted PS-MSSI-HT-LLE protocols allowed re-extraction and further pre-concentration of target analytes in the diluted acid samples for simultaneous electrochemical quantification at low concentration levels. To improve the peak separation, in simultaneous detection, a baseline-corrected second-order derivative approach was processed. These approaches allowed quantification of target FQs from animal food samples spiked at levels of 0.80 to 2.00 µmol L−1 in chicken meat, with recovery values always higher than 80.5%, as well as in milk samples spiked at 4.00 µmol L−1, with recovery values close to 70.0%.

O desenvolvimento de aplicativos acessiveis e um grande desafio ainda nos dias atuais, apesar dos exponenciais avancos tecnologicos. Problemas de dificuldade de navegacao pelos usuarios com deficiencia visual sao cada vez mais importantes para designers e desenvolvedores. Este artigo descreve elementos teoricos utilizados na confeccao do Controle Facil, um aplicativo de gerenciamento financeiro desenvolvido tendo como um de seus objetivos a acessibilidade para pessoas com deficiencia visual. Descrevemos seu processo de desenvolvimento, prototipos com niveis diferentes de complexidade e avaliacao realizada com usuarios, onde foi possivel validar uma serie de requisitos para aplicacoes e construir um guia para desenvolvimento de aplicativos acessiveis para smartphones.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:17Z No. of bitstreams: 1 S0100-46702006000200007.pdf: 394003 bytes, checksum: ff62121b50fd013e9d4d11151390c8e7 (MD5) Made available in DSpace on 2013-08-22T18:49:17Z (GMT). No. of bitstreams: 1 S0100-46702006000200007.pdf: 394003 bytes, checksum: ff62121b50fd013e9d4d11151390c8e7 (MD5) Previous issue date: 2006-01-01 Made available in DSpace on 2013-09-30T19:09:35Z (GMT). No. of bitstreams: 2 S0100-46702006000200007.pdf: 394003 bytes, checksum: ff62121b50fd013e9d4d11151390c8e7 (MD5) S0100-46702006000200007.pdf.txt: 25394 bytes, checksum: 35a66a78e87eb7ece304c8bfeac5fe87 (MD5) Previous issue date: 2006-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:19:51Z No. of bitstreams: 2 S0100-46702006000200007.pdf: 394003 bytes, checksum: ff62121b50fd013e9d4d11151390c8e7 (MD5) S0100-46702006000200007.pdf.txt: 25394 bytes, checksum: 35a66a78e87eb7ece304c8bfeac5fe87 (MD5) Made available in DSpace on 2014-05-20T14:19:51Z (GMT). No. of bitstreams: 2 S0100-46702006000200007.pdf: 394003 bytes, checksum: ff62121b50fd013e9d4d11151390c8e7 (MD5) S0100-46702006000200007.pdf.txt: 25394 bytes, checksum: 35a66a78e87eb7ece304c8bfeac5fe87 (MD5) Previous issue date: 2006-01-01 Um método envolvendo a pré-concentração e redissolução anódica em condições de voltametria de pulso diferencial empregando um eletrodo de pasta de carbono modificado (EPCM) com uma resina de troca iônica Amberlite IR120 foi proposto para a determinação de íons chumbo em álcool combustível. O procedimento é baseado em um pico de oxidação do analito observado em -0,53 V(vs. Ag/AgCl) em solução de HCl. As melhores condições experimentais encontradas foram: 5% (m/m) da Amberlite IR120 para a construção do eletrodo, solução de HCl 0,1 mol L-1, velocidade de varredura de 10 mVs-1, tempo de pré-concentração de 15 min e amplitude de pulso de 100 mV. Utilizando essas condições, o EPCM apresentou uma resposta linear entre a corrente de pico anódica e a concentração de íons chumbo para o intervalo entre 9,9 x 10-9 e 1,2 x 10-6 mol L-1 e um limite de detecção de 7,2 x 10-9 mol L-1. Valores de recuperação entre 96 % e 102 % foram encontrados para amostras de álcool combustível enriquecidas com Pb2+ em níveis de 10-7 mol L-1. O efeito da presença de outros íons concomitantes sobre a resposta voltamétrica do eletrodo também foi avaliado. The use of pre-concentration and differential pulse anodic stripping voltammetry (DPASV) using a carbon paste electrode modified (CPEM) with ion-exchange resin (Amberlite® IR120) has been proposed for the determination of lead ions content in ethanol fuel. The lead oxidation peak was observed at -0.53 V (vs. Ag/AgCl) in HCl solution. The best DPASV response was reached for an electrode composition of 5% (m/m) Amberlite® IR120 in the paste, 0.1 mol L-1 HCl solution, scan rate of 10 mVs-1, pre-concentration time of 15 min and potential pulse amplitude of 100 mV. In these experimental conditions, the proposed methodology responds to lead ions in the concentration range of 9.9 x 10-9 to 1.2 x 10-6 mol L-1 with a detection limit of 7.2 x 10-9 mol L-1. Recoveries ranged from 96 to 102 % for Pb(II) spiked in an ethanol fuel sample at 10-7 mol L-1 level were achieved. Interferences were also evaluated. Universidade Estadual Paulista Instituto de Química Departamento de Química Analítica Universidade Estadual Paulista Instituto de Química Departamento de Química Analítica

Voltammetry and amperometry are inexpensive and high-performance analytical techniques. However, their lack of selectivity limits their use in complex matrices such as biological, environmental, and food samples. Therefore, voltammetric and amperometric analyses of these samples usually require time-consuming and laborious sample pretreatments. In this study, we present a simple and cost-effective approach to fabricate a miniaturized electrochemical cell that can be easily coupled to a head space-like gas extraction procedure in such a way the sample pretreatment and voltammetric detection are performed in a single step. As a proof of concept, we have used the proposed system to quantify sulfite in beverage samples after its conversion to SO2(g). Despite the simplicity and low cost of the proposed system, it provided good analytical performance and a limit of detection of 4.0 μmol L−1 was achieved after only 10 min of extraction. The proposed system is quite versatile since it can be applied to quantify any volatile electroactive species. Also, the proposed system provides a unique way to assess real-time extraction curves, which are essential to study and optimize new gas extraction procedures. Therefore, the approach described in this study could contribute to both applied and fundamental Analytical Chemistry.

A simple and inexpensive procedure of paper-based electrode (PE) fabrication using A4 size conventional paper, nail polish and carbon powder is reported. The device was prepared by spreading the carbon conductive ink directly onto the paper substrate using a paint-brush. The best composition of the conductive ink was 80:20% (m:m) carbon powder: nail polish and the best device was obtained with 100 mg (2.5 mg cm−2) of carbon conductive ink spread on the paper piece. The proposed device showed satisfactory stability in acidic, neutral and alkaline medium in presence of ferrocyanide ion used as electrochemical probe. Dopamine was selected as a target compound to evaluate the possibility of using the proposed device for electroanalytical purposes. Differential pulse voltammetry was used in these studies and dopamine detection was achieved at +0.13 V vs. Ag/AgClsat in phosphate buffer solution pH = 7 with a detection limit of 5.2 μmol L−1. The proposed device represents an interesting advance in the field of PE construction since it combines satisfactory electrochemical stability and electroanalytical performance with simplicity and widely available low-cost materials. Moreover, chemical modifiers can be easily added to the conductive ink. Therefore, this versatile device brings exciting possibilities for future electroanalytical applications mainly for those that require small and/or flexible devices, such as the amperometric detection in microfluidic systems.

The monitoring of species of medical, environmental, and industrial interests has been urgently demanded. Several times, the necessity of point of care and/or point of use is important to obtain precise and rapid quantification, in which wearable and flexible disposable electrochemical sensors and biosensors have been great alternatives. In this context, a short review describing the main advances in the fabrication and development of conductive inks for the construction of miniaturized and disposable electrochemical devices is presented. Electrochemical devices developed from conductive inks have been an innovative system that promotes flexibility for the design of the electrodes. The growing increase in the number of researches regarding the development of inks is driven by the search for simplicity, low-cost, less waste generation, mass production, and environmentally friendly manufacturing methods. The present review focuses on alternative conductive inks and their compounds, binders, and conductive materials for electrochemistry. The binder such as varnishes, natural resins, and natural polymeric compounds will be presented, once they promote the dispersion of conductive material, as well as the adhesion on the substrate. Special attention is given to conductive materials. We highlight some nanostructured materials such as platinum, silver, and gold nanoparticles, due to their great conductivity and extensive use to develop electrochemical sensors. Inks and electrodes from carbon-based materials are also discussed, such as graphite, carbon nanotubes, carbon black, and graphene. The biocompatibility of these materials, especially important for wearable sensors, will also be approached. Finally, we present new perspectives on the development of sensors and biosensors using conductive inks.

User studies have revealed that programmers face several obstacles when learning application programming interfaces (APIs). A considerable part of such difficulties relate to discovery of API elements and the relationships among them. To address discoverability problems, we show how to complement APIs with design annotations, which document design decisions in a program-processable form for types, methods, and parameters. The information provided by the annotations is consumed by the integrated development environment (IDE) in order to assist API users with useful code completion proposals regarding object creation and manipulation, which facilitate API exploration and learning. As a proof of concept, we developed Dacite, a tool which comprises a set of Java annotations and an accompanying plugin for the Eclipse IDE. A user study revealed that Dacite is usable and effective, and Dacite’s proposals enable programmers to be more successful in solving programming tasks involving unfamiliar APIs. info:eu-repo/semantics/publishedVersion

Made available in DSpace on 2018-12-11T17:10:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-26 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundação para a Ciência e a Tecnologia An electrochemical sensor for the determination of 3,5,6-trichloro-2-pyridinol (TCP), the main metabolite of the pesticide chlorpyrifos, was herein developed. TCP has greater solubility than the source pesticide, and its occurrence in ground and surface water is more frequent and more dangerous. The sensor was fabricated using carbon paste modified with the inorganic complex chloro-5,10,15,20-tetrakis-(pentafluorophenyl)-21 H,23 H-porphyrin iron(III) (FeTPPCl); this metallic complex has a chemical core structure similar to the heme cofactor of the cytochrome P450 (CYPs). Measurements were performed with square-wave voltammetry. Using the optimised voltammetric parameters and without any sample preparation, the sensor showed a limit of detection of 2.8 mg L−1 (14 μmol L−1), recoveries ca. 102%, suitable selectivity and long durability (over 1 month). Departamento de Química Analítica Instituto de Química UNESP-Univ Estadual Paulista REQUIMTE/LAQV Departamento de Química e Bioquímica Faculdade de Ciências Universidade do Porto (FCUP) Departamento de Química Analítica Instituto de Química UNESP-Univ Estadual Paulista CNPq: 153409/2010-0 FAPESP: 2016/06926-0 CNPq: 400459/2012-4 Fundação para a Ciência e a Tecnologia: SFRH/BPD/76544/2011

Este trabalho descreve o desenvolvimento de uma celula eletroquimica miniaturizada para ser aplicada em experimentos didaticos envolvendo voltametria ciclica. O principal objetivo e propor um experimento para cursos de graduacao que respeite os conceitos da Quimica Analitica Verde e envolva o aprendizado de alguns conceitos de eletroquimica e quimica analitica. As tecnicas eletroanaliticas sao exemplos de praticas “verde” de analise, pois normalmente utilizam pequenos volumes de solucao, possuem alta sensibilidade e sao facilmente miniaturizadas e automatizadas. Assim, o entendimento dos conceitos eletroquimicos e de grande importância aos alunos e, para auxilia-los, experimentos didaticos que respeitem o meio ambiente e empreguem materiais alternativos de baixo custo sao extremamente bem vindos. Neste contexto, este trabalho demonstra que uma celula miniaturizada construida com ponteiras de micropipetas pode ser empregada com exito no estudo de processos eletrodicos reversiveis por voltametria ciclica. A celula eletroquimica proposta nao apenas apresenta o mesmo desempenho de uma celula eletroquimica de tamanho convencional, como tambem reduz drasticamente o consumo de reagentes e a geracao de residuos quimicos.

Word completion interfaces are ubiquitously available in mobile virtual keyboards; however, there is no prior research on how to design these interfaces for screen reader users. In addressing this, we propose a design space for nonvisual representation of word completions. The design space covers seven categories aiming to identify challenges and opportunities for interaction design in an unexplored research topic. It is intended to guide the design of novel interaction techniques, serving as a framework for researchers and practitioners working on nonvisual word completion. To demonstrate its potential, we engaged blind users in an exploration of the design space, to create their own bespoke word completion solutions. Through this study we found that users create alternative interfaces that extended current screen readers' capabilities. Resulting interfaces are less conservative than mainstream solutions on notification frequency and cardinality. Customization decisions were based on perceived benefits/costs and varied depending on multiple factors such as users' perceived prediction accuracy, potential keystroke gains, and situational restrictions.

Over the years, it was possible to perceive an increasing inclusion of those with some type of disability, especially individuals with severe or moderate visual impairment. In the literature, it was similarly possible to note a higher interest in studies regarding accessibility, digital inclusion, and even greater humanization for this part of the population that used to be neglected (more than a quarter of the population in several countries). However, there is still a real lack of critical analysis, research and more appropriate and adequate references about improvements in accessibility aspects for individuals with motor and hearing impairments. Given this scenario and considering GuAMA as a mobile application accessibility guide, which is currently focused on visual impairments, this paper aims to present the continuous research process that extends GuAMA with new requirements to improve the mobile accessibility for the motor and hearing disability groups.

This study describes the use of uncured polydimethylsiloxane (PDMS) as a binder agent to prepare carbon paste electrodes (CPEs). A comparative study between the properties of CPEs prepared with PDMS and mineral oil Nujol®, the most common binder agent for CPEs, was carried out. Cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry showed that PDMS-CPEs presented higher electrical conductivity, active electrochemical area, and wider useful potential window compared with Nujol®-CPEs. Moreover, PDMS-CPEs were more stable in aqueous mixtures containing 50% (v/v) of ethanol or methanol than Nujol®-CPEs. PDMS-CPEs have also provided higher sensitivity and lower limit of detection to propranolol than Nujol®-CPE. Therefore, this study demonstrated that PDMS is a promising alternative binder agent able to produce CPEs with superior chemical/electrochemical stability and improved analytical performance.

This study was made over some database of accessibility principles, to investigate the state of the art of contemporary design topics about accessibility in mobile applications, while comparing the WCAG 2.1 and the Guide for Development of Accessible Mobile Applications (GUAMA) in a case study with the Samsung Audio Acordes (Chords), an app developed for teaching guitar for blind people. The results will serve to propose revisions/new protocols which allow to evaluate and sketch more accessible versions of these kind of digital products, helping development teams, designers, testers, etc., to improve the experiences for users with disabilities into new more accessible mobile applications.

This paper aims to describe the application of protocol and presentation of results of a Virtual Assistants (VAs) evaluation in the field of mobile devices, in their relation of use with People with Motor Disability (PMDs) with limitation in the Upper Limbs. To that end, aspects directly linked to accessibility were the focal points for this issue. The research reported in this present is characterized as exploratory, due to the understanding of the problem by the researchers and the academy still need more in-depth. In this way, the presentation of preliminary data could provide more information on the subject investigated, besides allowing a better delineation of future research. Various insights are possible with such an application that aims to improve the interaction of this public with digital devices through VAs. This same research procedure has already been adopted and replicated with People with Visual Disabilities (PVDs) with prodigious results not just for this kind of audience, but for People with Disabilities in general.

The human perception of the performance of an operation while interacting with an user interface (UI) is subjective, i.e., it may depend on how the visual elements are arranged and how they respond to actions. The research for techniques for measurement of UI response time is a nontrivial task, since most of the solutions are concentrated in specific technologies. For evaluation of web pages, tools of general purpose has been used, focusing only on the download of resources and recommendations for the code structure. This paper proposes a methodology to make feasible the measurement of scenarios specified by the product designers for both web and mobile native applications with minor modifications in the automated test code. The methodology relies on using popular automation test tools originally designed for functional testing. The results found may help product owners and stakeholders to make cost-benefit analysis and make decisions about possible enhancements taking into account how the end user interacts with the application.

Continuous Delivery refers to a software development practice where members of a team frequently integrate their work, so that the process of delivery can be easily conducted. However, this continuous integration and delivery requires a reliable collaboration between development and IT operation teams. The DevOps practices support this collaboration since they enable that the operation staff making use of the same infrastructure as developers for their systems work. Our study aims at presenting a practical DevOps implementation and analyzing how the process of software delivery and infrastructure changes was automated. Our approach follows the principles of infrastructure as code, where a configuration platform – PowerShell DSC – was used to automatically define reliable environments for continuous software delivery. In this context, we defined the concept of “stage for dev”, also using the Docker technology, which involves all the elements that enable members of a team to have the same production environment, locally configured in their personal machines and thus empowering the continuous integration and delivery of system releases.

The technology of virtual assistants (VAs) is a powerful option to support the interaction of human users with computational systems. These VAs are able, for example, to identify interaction problems and offer recommendations on the execution of commands. This work analyses the use of VAs as a resource of accessibility for mobile devices. This analysis was carried out by means of a literature review, which considered both academic studies and commercial solutions. The results showed that there are very few researches in this area and this fact motivated the development of an evaluation protocol, and related set of tests cases, which can verify if current VAs are in fact able to support the interaction of motor and visually impaired users with their mobile devices.

This work presents a voltammetric method for Zn2+ determination in antiseptic dusting powder and multivitamin commercial samples, combining an alkaline extraction using NaOH aqueous solution with a carbon paste electrode chemically modified with Bi anchored on Amberlite® IR120 ion exchange resin (CPEAmb/Bi). The best conditions for electrode preparation were: 10% (m/m) of Amberlite® IR 120; 30 s Bi3+ accumulation time (open circuit) in 0.5 mmol L-1 Bi3+ solution prepared in 0.1 mol L-1 acetate buffer (pH = 5.5). The analytical curve for Zn2+ using the CPEAmb/Bi presented linear range from 0.05 to 8.2 µmol L-1 and the limit of detection was 10 nmol L-1. The voltammetric method was simple, fast, efficient and low-cost for the Zn2+ determination in antiseptic dusting powder and multivitamin samples.

PandionJ is a pedagogical debugger that provides users with rich visualizations of program state that resemble teacher-drawn illustrations. Its design was driven by a study that investigated how programming teachers illustrate variables, transposing illustration patterns into the tool. These illustrations require static analysis of the source code to infer relationships between variables. We describe the innovative features of the tool regarding how it addresses program variables. The tool was adopted in an introductory programming course, and the pass rates of the first course edition using it were significantly higher when compared to the three previous editions.

Miniaturization of analytical devices is a new and perhaps the ultimate trend in analytical chemistry. However, many microfabrication techniques could be inaccessible for researchers from developing countries where research funding is routinely scarce. Thus, in this study, we describe an approach to fabricate an inexpensive and durable miniaturized electrochemical sensor using micropipette tips and metallic wires recovered from a damaged combined glass electrode and a conductance cell. The analytical performance of this device was evaluated for some selected electroactive compounds at static and hydrodynamic conditions either in aqueous or ethanol/aqueous solutions. The working electrode was modified with carbon nanotubes and the miniaturized device was used to determine the fungicide carbendazim in water and orange juice samples. Despite the simplicity and low cost of the proposed device, its analytical performance was comparable with more sophisticated electrodes, and its compatibility with flowing conditions and organic solvents suggests that it could be used as an amperometric detector in liquid chromatography or milifluidic devices. Therefore, we believe this study is valuable for research groups with funding limitations and it could be a way to include them in the field of microanalysis which is one of the most promising and exciting branches of Analytical Chemistry.

This study describes the fabrication of carbon screen-printed electrodes (SPEs) from alternative and low-cost materials. The carbon conductive ink was prepared from a mixture of graphite powder and colorless nail polish. To produce the SPEs, the ink was spread on polyester overhead projector sheets, which acted as a flexible and water-impermeable substrate. To improve the analytical performance, the SPEs were chemically modified with multiwalled carbon nanotubes (MWCNTs) by a simple drop-casting procedure. The effects of the acidic functionalization and size of the MWCNTs on the electrochemical behavior of the SPEs were evaluated. As a proof of concept, the MWCNT/SPEs were applied to determine caffeic acid (CA) in tea samples. CA is a biologically important molecule with antioxidant activity and several beneficial effects on human health, therefore its determination in food and beverages is relevant. The SPEs modified with the acidic-functionalized longer diameter MWCNTs presented the broadest linear range for CA, from 2.0 µmol L−1 to 50 µmol L−1. These MWCNTs also provided low limits of detection and quantification, 0.20 and 0.66 µmol L−1, respectively. Tea samples were analyzed by using these electrodes and recovery percentages from 99 to 109% were obtained with low relative standard deviation values, demonstrating the accuracy of the proposed sensor. Moreover, the developed SPE allowed performing the voltammetric measurements using only 100 µL of solution which is extremely attractive from an economical and environmental point of view. Therefore, this study brings exciting advances in the electroanalysis field regarding the importance of the development of disposable electrochemical sensors with improved performance and capability to perform electrochemical measurements in microvolumes.

Empirical study that formally defines TD grounded in a real-world example.Concept map that indicates the appropriate variables for a cost-benefit analysis.Case history built and analyzed from a heterogeneous corpus of data.Empirical evidence for many important concepts related to TD.TD case description carried out around project decisions. The Technical Debt (TD) metaphor has been used as a way to manage and communicate long-term consequences that some technical decisions may cause. Although intuitive, a lack of practical analysis and demonstrations defers its dissemination over the software community. This exploratory study applied two research methods to characterize the effects associated with a TD item during six years of a real software project lifecycle. First, a quantitative analysis was carried out to characterize the TD item in terms of concrete numbers. Then, Grounded Theory techniques were used to identify categories, properties and their relations, which could together provide a fuller definition of the TD metaphor. The resultant Grounded Theory, in the form of a concept map, confirmed some elements already identified by the technical literature, but also raised up new concepts that should be considered during analysis of TD items. Thus, this work contributes to the effort in building a formal theory about TD and provides directions to assist the work of developers/managers who intend to identify and monitor TD items in their projects, given the practical nature of this study.

Summary Plugin-based systems are typically realized with resort to a component framework that offers an infrastructure for assembling plugin components, which can be composed to form system variants. Feature models have been proposed as an abstraction to manage software variability, where feature configurations describe variants of a software system. In this paper, we propose an automated approach to map the artifacts of plugin-based component frameworks to feature models. We describe a methodology for structuring the architecture of a plugin-based system, so that the variability space and variants are reflected in a feature model and its configurations. We materialized the proposed approach for the Eclipse Equinox component framework in a tool to visualize the variability of plugin-based systems in feature diagrams, which can be used to generate system variants. We carried out an experiment where we developed a small plugin-based product line on top of Equinox in the context of an advanced software development course. Copyright © 2016 John Wiley & Sons, Ltd.

Composting is a feasible, environmentally-friendly management tool for the treatment of animal manures based on nutrient recovery. However, the liquid character of the pig slurry, with low dry matter, requires previous solid–liquid separation and the mixture of the solid fraction with an adequate bulking agent in the correct ratio. This work studies the influence of the bulking agent proportion on the composting of the solid fraction of pig slurry, focussing on the development of the process and on the greenhouse gas emissions. For this, two mixtures of the solid fraction of pig slurry and cotton gin waste, in different proportions, were prepared (4:3 and 3:4 solid fraction of pig slurry:cotton gin waste, v:v) and composted by the Rutgers static pile system in a pilot plant (2000 kg each pile). The temperature profiles of the composting piles were similar, but the pile with the greater proportion of bulking agent showed higher temperatures and a longer thermophilic phase, with greater aeration demand. The specific heat capacity of cotton is lower than those of other bulking agents used frequently for animal manure composting, which means that this material requires less energy from microbial activity for its temperature to increase. However, the easily degradable organic matter present in the pig slurry explained the faster organic matter mineralisation occurred in the pile with the higher proportion of solid fraction of pig slurry; in pile with higher proportion of bulking agent, the mineralisation process was slower due to the lignocellulosic character of the cotton gin waste. The organic matter mineralisation was closely related to the gaseous emissions (mainly as carbon dioxide): significant methane emissions were detected when the highest organic matter degradation occurred in the pile with the greater proportion of solid fraction of pig slurry, together with the highest nitrogen oxide emissions – indicating the existence of anaerobic pockets within the composting mass. So, it can be concluded that the thermal properties of the bulking agent were responsible for the temperature development and aeration demand, while the gaseous emissions were related to the organic matter degradation process. The composts produced were stable, with a good degree of maturation; the compost with the higher proportion of solid fraction of pig slurry had greater organic matter humification and higher nutrient concentrations.

In this study, a carbon paste electrode was used for the amperometric detection of atenolol (ATN) in a Flow Injection Analysis (FIA) system with recirculation of the carrier solution. Under optimized conditions, the FIA method presented a linear range from 50 to 1000 μmol L−1, with a limit of detection of 8 μmol L−1 and a limit of quantification of 50 μmol L−1. The proposed method was successfully employed for ATN determination in five pharmaceutical formulation samples without interference from pharmaceutical excipients or the concomitant drugs chlortalidone and nifedipine. Recirculation of the carrier solution combines the advantages of using high flow rates (7 mL min−1), i.e. high sensitivity and high analytical frequency (240 injections per h), with very low reagent consumption and waste generation. A non-modified carbon paste electrode as an amperometric detector provides simplicity and low cost to the analytical method. Therefore, the proposed FIA method allows ATN quantification in pharmaceutical formulation samples in a very fast, inexpensive, reliable and environmentally friendly way.

Nowadays, there is growing interest in portable and disposable electrochemical sensors due to the low-cost, simplicity, and excellent analytical performance associated with these devices. Despite recent advances, however, there remains a need to create cheap, high-performance electrode materials. Thus, this study evaluated the suitability of carbon conductive inks prepared by the mixture of glass varnish and graphite powder to produce disposable electrochemical sensors. Two different ink manufacturing processes and compositions were studied to produce different disposable electrodes, each providing high electrical conductivity and adhesion on paper and polyethylene terephthalate (PET) substrates. Electrochemical impedance spectroscopy, scanning electron microscopy, and Fourier-transform infrared spectroscopy were used for the characterization of inks. The electrodes were applied for the electrochemical determination of some compounds. For the paper electrode, the electrochemical detection of dopamine was performed, ranging from 15 μmol to 100 μmol L−1, with a detection limit of 4.1 μmol L−1; the individual electrochemical detection of catechol was performed ranging from 10 μmol L−1 to 1000 μmol L−1, with a detection limit of 9.0 μmol L−1. The detection of hydroquinone was performed, ranging from 10 μmol L−1 to 1000 μmol L−1, with a detection limit of 5.3 μmol L−1. Also, the screen-printed electrode was applied for estriol electrochemical determination in the linear range from 0.1 μmol L−1 to 8.0 μmol L−1 with a detection limit of 0.08 μmol L−1. The glass varnish is an alternative to creating carbon composite electrodes, and the new devices are inexpensive and simple to prepare, with attractive analytical performance.

Our current project involves the use of a multistage research method to specify a guideline for mobile applications, which intends to support visually impaired users. This paper discusses the employment of this guideline along the development of a mobile application for personal financial management. Such application was evaluated by a group of visually impaired volunteers and the evaluation results were used as a source of insights to refine the guideline and its requirements. Qualitative interviews show that the guideline ensures a higher level of usability when compared to previous experiences of volunteers with other applications. Thus, such outcomes confirm the guideline potential as a resource to support the development of a brand new set of accessible applications.3-Our current project involves the use of a multistage research method to specify a guideline for mobile applications, which intends to support visually impaired users. This paper discusses the employment of this guideline along the development of a mobile application for personal financial management. Such application was evaluated by a group of visually impaired volunteers and the evaluation results were used as a source of insights to refine the guideline and its requirements. Qualitative interviews show that the guideline ensures a higher level of usability when compared to previous experiences of volunteers with other applications. Thus, such outcomes confirm the guideline potential as a resource to support the development of a brand new set of accessible applications.

In the past years, captures made by dual-fisheye lens cameras have been used for virtual reality, 360 broadcasting and many other applications. For these scenarios, to provide a good- quality experience, the alignment of the boundaries between the two images to be stitched must be done properly. However, due to the peculiar design of dual-fisheye cameras and the high variance between different captured scenes, the stitching process can be very challenging. In this work, we present a 360 stitching solution based on feature cluster matching. It is an adaptive stitching technique based on the extraction of feature cluster templates from the stitching region. It is proposed an alignment based on the template matching of these clusters, successfully reducing the discontinuities in the full-view panorama. We evaluate our method on a dataset built from captures made with an existing camera of this kind, the Samsung's Gear 360. It is also described how we can extend these concepts from image stitching to video stitching using the temporal information of the media. Finally, we show that our matching method outperforms a state-of-the-art matching technique for image and video stitching.

In this work we address the problem of landmark recognition. We extend PlaNet, a model based on deep neural networks that approaches the problem of landmark recognition as a classification problem and performs the recognition of places around the world. We propose an extension of the PlaNet technique in which we use a voting scheme to perform the classification, dividing the image into previously defined regions and inferring the landmark based on these regions. The prediction of the model depends not only on the information of the features learned by the deep convolutional neural network architecture during training, but also uses local information from each region in the image for which the classification is made. To validate our proposal, we performed the training of the original PlaNet model and our variation using a database built with images from Flickr, and evaluated the models in the Paris and Oxford Buildings datasets. It was possible to notice that the addition of image division and voting structure improves the accuracy result of the model by 5-11 percentage points on average, reducing the level of ambiguity found during the inference of the model.