Cookies
O website necessita de alguns cookies e outros recursos semelhantes para funcionar. Caso o permita, o INESC TEC irá utilizar cookies para recolher dados sobre as suas visitas, contribuindo, assim, para estatísticas agregadas que permitem melhorar o nosso serviço. Ver mais
Aceitar Rejeitar
  • Menu
Publicações

Publicações por CRIIS

2017

Autonomous UAV outdoor flight controlled by an embedded system using odroid and ROS

Autores
Carvalho, JP; Jucá, MA; Menezes, A; Olivi, LR; Marcato, ALM; dos Santos, AB;

Publicação
Lecture Notes in Electrical Engineering

Abstract
Unmanned Aerial Vehicles (UAVs) have become a prominent research field due to their vast applicability and reduced size. An appealing aspect of theUAVs is the ability to accomplish autonomous flights in several contexts and purposes, and a variety of applications have been developed, from military to civilian fields. The system proposed in this work is a novel and simplified interaction between the user and the UAV for autonomous flight, where the necessary computation is performed in an embedded computer, decreasing response time and eliminating the necessity of long-distance communication links with base stations. Results are presented with both hardware in the loop simulations and a real UAV using Pixhawk, and Odroid and ROS as companion computer and software platform for code development. © Springer International Publishing Switzerland 2017.

2017

FTIR chemometrical approach for clonal assessment: Selection of <i>Olea europaea</i> L. optimal phenotypes from cv. Cobrancosa

Autores
Machado, M; Machado, N; Gouvinhas, I; Domínguez Perles, R; Barros, AIRNA;

Publicação
JOURNAL OF CHEMOMETRICS

Abstract
Fourier transform infrared spectroscopy has been applied in tandem with multivariate statistical approaches, with the prospect of developing a methodology for the prediction of interesting traits in distinct clones of “Olea europaea L.” For this purpose, the infrared spectra of either the drupes or the corresponding olive oils of 6 distinct clones of the Cobrançosa cultivar, in 2 ripening stages (semi-ripe and ripe), have been registered resorting to an attenuated total reflection accessory. These clones were previously evaluated with respect to antioxidant activity and olive oil yield, while multivariate analyses, namely, partial least squares regression and discriminant analysis have been applied to the spectral data collected to obtain a prediction model for the assessment of these traits in distinct clones through the infrared spectra. This methodology leads to minimal erroneous classification rates in the validation procedure of 3.9% and 6.3% for olives and olive oils, respectively, using the first derivative of the spectra. Thus, the suitability of this methodology for the assessment of different clones has been shown with visible benefits for a time consuming and costly process such as clonal selection. Furthermore, this procedure might be extended for other cultivars or different species once proper calibration models are attained for each matrix. Copyright © 2017 John Wiley & Sons, Ltd.

2017

Critical Review on the Significance of Olive Phytochemicals in Plant Physiology and Human Health

Autores
Gouvinhas, I; Machado, N; Sobreira, C; Dominguez Perles, R; Gomes, S; Rosa, E; Barros, AIRNA;

Publicação
MOLECULES

Abstract
Olive oil displays remarkable organoleptic and nutritional features, which turn it into a foodstuff appreciated by consumers, and a basic component of the Mediterranean diet. Indeed, the noticed benefits of including olive oil in the diet have been assigned to the presence of diverse bioactive compounds with different molecular structures. These compounds confer a wide range of biological properties to this food matrix, including the prevention of distinct human diseases as well as the modulation of their severity. The most relevant bioactive compounds present in olive oil correspond to benzoic and cinnamic acids, phenolic alcohols and secoiridoids, and also flavonoids. Over the last decades, several studies, devoted to gaining a further insight into the relative contribution of the separate groups and individual compounds for their biological activities, have been conducted, providing relevant information on structure-activity relationships. Therefore, this paper critically reviews the health benefits evidenced by distinct phenolic compounds found in olive oils, thus contributing to clarify the relationship between their chemical structures and biological functions, further supporting their interest as essential ingredients of wholesome foods.

2017

Addressing Facts and Gaps in the Phenolics Chemistry of Winery By-Products

Autores
Machado, NFL; Dominguez Perles, R;

Publicação
MOLECULES

Abstract
Grape and wine phenolics display a noticeable structural diversity, encompassing distinct compounds ranging from simple molecules to oligomers, as well as polymers usually designated as tannins. Since these compounds contribute critically to the organoleptic properties of wines, their analysis and quantification are of primordial importance for winery industry operators. Besides, the occurrence of these compounds has been also extensively described in winery residues, which have been pointed as a valuable source of bioactive phytochemicals presenting potential for the development of new added value products that could fit the current market demands. Therefore, the cumulative knowledge generated during the last decades has allowed the identification of the most promising compounds displaying interesting biological functions, as well as the chemical features responsible for the observed bioactivities. In this regard, the present review explores the scope of the existing knowledge, concerning the compounds found in these winery by-products, as well as the chemical features presumably responsible for the biological functions already identified. Moreover, the present work will hopefully pave the way for further actions to develop new powerful applications to these materials, thus, contributing to more sustainable valorization procedures and the development of newly obtained compounds with enhanced biological properties.

2017

Anomalous surface-enhanced Raman scattering of aromatic aldehydes and carboxylic acids

Autores
Machado, NFL; Marques, MPM; de Carvalho, LAEB; Castro, JL; Otero, JC;

Publicação
JOURNAL OF RAMAN SPECTROSCOPY

Abstract
Raman and SERS spectra of benzaldehyde (Bz-CHO) and chromone-3-carboxaldehyde (Ch-CHO) on silver colloids have been analyzed, being subsequently compared to the spectra of the corresponding acids. In the SERS spectra of both aldehydes, the band corresponding to the.(C =O) stretching mode of the carboxaldehyde group at ca. 1700cm (-1) ismissing, while a newband at 13501400cm(-1), characteristic of the symmetric stretching mode of carboxylate group, is appearing in both cases. These results point out that aldehydes are oxidized to their corresponding acidswhen adsorbed on silver nanoparticles. This conclusion has been confirmed by means of HPLC-MS analysis and supported on the basis of DFT calculations. Copyright (c) 2016 John Wiley & Sons, Ltd.

2017

Evaluating the freezing impact on the proximate composition of immature cowpea (Vigna unguiculata L.) pods: classical versus spectroscopic approaches

Autores
Machado, N; Oppolzer, D; Ramos, A; Ferreira, L; Rosa, EAS; Rodrigues, M; Dominguez Perles, R; Barros, AIRNA;

Publicação
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE

Abstract
BACKGROUND: Freezing represents a common conservation practice regarding vegetal foodstuffs. Since compositional features need to be monitored during storage, the development of rapid monitoring tools suitable for assessing nutritional characteristics arises as a pertinent issue. In this study, cowpea (Vigna unguiculata L.) pods, both fresh and after 6 and 9 months of freezing at -18 degrees C, were evaluated by high-performance liquid chromatography for their content of protein as well as of essential and nonessential amino acids, while their Fourier transform infrared spectra in the mid infrared (MIR) and near infrared (NIR) ranges were concomitantly registered to assess the feasibility of this approach for the traceability of these frozen matrices. RESULTS: For the NIR interval, the application of the 1st derivative to the spectral data retrieved the best results, while for lower concentrations the application of the Savitzky-Golay algorithm was indispensable to achieve quantification models for the amino acids. MIR is also suitable for this purpose, though being unable to quantify amino acids with concentrations below 0.07 mmol g(-1) dry weight, irrespective of the data treatment used. CONCLUSIONS: The spectroscopic approach constitutes a methodology suitable for monitoring the impact of freezing on the nutritional properties of cowpea pods, allowing accurate quantification of the protein and amino acid contents, while NIR displayed better performance. (C) 2017 Society of Chemical Industry

  • 257
  • 399