276 research outputs found
Biomechanics of a pedestrian accident reconstruction
Pedestrians represent about 20% of the overall fatalities in Europe's road traffic accidents, as well as in Portugal. An in-depth investigation, accident reconstruction, is mandatory in order to analyze with care fundamental aspects of an accident. Detailed information about the injuries and injury causation mechanisms are with great use for it. Accident reconstruction computational techniques using pedestrian biomechanical models are used to evaluate the accident conditions that lead to major pedestrian injuries, such as the vehicle's speed and the impact location. For biomechanical injury criterions, the AIS (Abbreviated Injury Scale), the HIC (Head Injury Criterion) and some other injury criterions are used.
Pedestrian's height, weight, gender, age, vehicle geometry (or category) and travelling speed, significantly influence the pedestrian injuries in the event of a road collision.
The use of injury scales and biomechanical criterions in the in-depth accident investigation of road accidents, such as AIS, can improve significantly the quality of the reconstruction process.
The computer simulation of vehicle-to-pedestrian collisions is fundamental for the study of the dynamics of these road accidents. Where did the pedestrian is when the vehicle hits him? Normally, there is no simple and clear answer. The pedestrian, if survives, states that he uses the crossway, the driver of the vehicle states otherwise, that the location of the pedestrian was much later than the pedestrian crossing.
This work presents an accident where only the use of accident reconstruction specialized software, PC-Crash, conjugated with all available information allowed the determination of the vehicle's speed and the Location of the pedestrian.info:eu-repo/semantics/publishedVersio
Development of an electrochemical RNA-aptasensor to detect human osteopontin
Electrochemical aptasensors may be used to detect protein biomarkers related to tumor activity. Osteopontin (OPN), a protein present in several body fluids, has been suggested as a potential biomarker since its overexpression seems to be associated with breast cancer progression and metastasis. In this work, a simple and label-free voltammetric aptasensor for the detection of OPN, using an RNA aptamer previously reported to have affinity for human OPN as the molecular recognition element, and the ferro/ferricyanide solution as a redox probe, was developed. The RNA aptamer was synthetized and immobilized in a working microelectrode gold surface (diameter of 0.8 mm) of a screen-printed strip with a silver pseudo-reference electrode and a gold counter electrode. The electrochemical behavior of the electrode surface after each preparation step of the aptasensor was studied using cyclic voltammetry and square wave voltammetry. The resulting voltammetric aptasensor was used to detect OPN in standard solutions. Cyclic voltammetry results showed that the aptasensor has reasonable detection and quantification limits (3.7±0.6 nM and 11±2 nM, respectively). Indeed, the detection limit falls within the osteopontin levels reported in the literature for patients with metastatic breast cancer. Moreover, the aptasensor is able to selectively detect the target protein in the presence of other interfering proteins, except for thrombin. Considering the overall results, a possible application of the aptasensor for cancer prognosis may be foreseen in a near future.FCT and FEDER under Program PT2020 (Project UID/EQU/50020/2013); by the Strategic Project PEst-OE/EQB/LA0023/2013 and by the project ref. RECI/BBB-EBI/ 0179/2012 (project number FCOMP-01-0124-FEDER-027462) funded by FCTFundação para a CiĂȘncia e a Tecnologia(FCT) through the PhD grant SRFH/BD/65021/2009
Aromatherapy in the control of stress and anxiety
Background: Currently, complementary and alternative medicine emerge as important therapies in the prevention and treatment of various health problems. In view of this, the present study aims to evaluate the efficacy of essential oils in reducing stress and anxiety levels in aromatherapy users, at a clinic of Bragança, Portugal.
Methods: A study was performed with 36 individuals divided in two distinct groups: âaroma groupâ and âcontrol groupâ. Individuals of "aroma group" were treated with a mixture of essential oils of Lavandula angustifolia Mill and Matricaria recutita L. applied with Effleurage massage while the individuals of "control group" received only Effleurage massage. Stress and anxiety levels of all individuals participating in the study were evaluated before and after the treatment. Additionally, the chemical composition of the essential oils was evaluated by GC and GC-MS.
Results: In the aromatherapy assay, the âaroma groupâ showed a significant decrease of 12% and 30%, in stress and anxiety levels, respectively, in the âcontrol groupâ this decrease was lower (3.3% and 2.6% for stress and anxiety levels, respectively).
Conclusion: In this study, aromatherapy was effective in stress and anxiety levels reduction and linalool, the major compound of the essential oil mixture, may be positively contributing for these effects.info:eu-repo/semantics/publishedVersio
A computational study of substituted flavylium salts and their quinonoidal conjugate-bases: S0 -> S1 electronic transition, absolute pKa and reduction potential calculations by DFT and semiempirical methods
The electronic transitions for flavylium cations and quinonoidal bases of 17 substituted flavylium salts have been studied at semiempirical and DFT (density functional theory) levels. Solvent effect on electronic spectra was included by Polarizable Continuum Model, PCM. We assigned longest-wavelength absorption maxima to HOMO -> LUMO transition. Both levels of theory gave good results for electronic transitions of flavylium cations whereas only TDDFT-PCM calculations could be used for electronic transitions of their quinonoidal bases. We also performed absolute pKa calculations of nine flavylium salts at DFT level. The pKa calculated values by our PCM parameterization gave excellent results with mean absolute deviation less than a half of one pKa unit. One-electron reduction potentials were carried out for 5 flavylium cations at DFT level. The theoretical results found were in good agreement with experimental values after adjustment for a systematic deviation
Aromatherapy: ancient solutions for recent problems
Background: Currently, complementary and alternative medicine emerge as strategy in the
prevention and treatment of various health problems. The present study aims to evaluate the efficacy
of aromatherapy with Lavandula angustifolia Mill and Matricaria recutita L. in reducing stress and
anxiety levels.
Methods: A study was performed with 36 individuals divided in two distinct groups: âaroma groupâ
and âcontrol groupâ. Individuals of "aroma group" were treated with a mixture of essential oils of
Lavandula angustifolia Mill and Matricaria recutita L. applied with Effleurage massage while the
individuals of "control group" received only Effleurage massage. Stress and anxiety levels of all
individuals participating in the study were evaluated before and after the treatment. Additionally, the
chemical composition of the essential oils was evaluated by GC and GC-MS.
Results: In the aromatherapy assay, the âaroma groupâ showed a significant decrease of 12% and
30%, in stress and anxiety levels, respectively while lower decrease was observed in âcontrol groupâ
(3.3% and 2.6% for stress and anxiety levels, respectively).
Conclusion: In this study, aromatherapy was effective in stress and anxiety levels reduction and
linalool, the major compound of the essential oil mixture, may be positively contributing for these
effects.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial
support by national funds FCT/MCTES to CIMO (UIDB/00690/2020).
The authors gratefully acknowledge the financial support provided by Fundação para a CiĂȘncia e a
Tecnologia (FCT) under UID/AMB/50017/2013, FEDER PT2020-Compete 2020. Authors are also grateful to Gabinete TerapĂȘutico Telmo Teles, Unipessoal, Lda, Bragança, for the availability to perform the aromatherapy assay.info:eu-repo/semantics/publishedVersio
Extending the Synoptics of Things (SoT) Framework to Manage ISoS Technology Landscapes
Managing and monitoring the software and hardware artifacts of an industrial organization are fundamental efforts that can often be challenging endeavors to achieve, especially when such technological landscapes are composed of multiple heterogeneous systems. Usually, Internet of Things (IoT) devices are provided by different suppliers and may use different protocols and interfaces. Thus, the integration of these devices results in complex development and maintenance cycles. The Synoptics of Things (SoT) framework can address these problems, in conjunction with the Informatics System of Systems (ISoS) platform by promoting an open market competitive tech nology landscape for organizations. The purpose of the research presented in this paper was to extend the SoT framework in order to manage and monitor the different elements of an ISoS enabled organization, namely the ISystems (Informatics Systems), CES (Cooperation Enabled Services), and Services. We argue that the SoT framework can be essential in a supervisory control and data acquisition (SCADA) system in todayâs modern web, by adopting the concept of Web Components as a standard to enable the development of custom and reusable components. We present and discuss such issues in the context of the HORUS system, an informatic system responsible for payment enforcement in fueling stations. In this system, several devices must work in coordination, such as video cameras and video recorders, which are fundamental for the retrieving of license plate images and, therefore, be continually monitored to ensure the correct functioning of the HORUS system.info:eu-repo/semantics/publishedVersio
Electronic tongue: a versatile tool for mineral and fruit-flavored waters recognition
Natural mineral waters (still), effervescent natural mineral waters (sparkling) and aromatized waters with fruit-flavors (still or sparkling) are an emerging market. In this work, the capability of a potentiometric electronic tongue, comprised with lipid polymeric membranes, to quantitatively estimate routinely quality physicochemical parameters (pH and conductivity) as well as to qualitatively classify water samples according to the type of water was evaluated. The study showed that a linear discriminant model, based on 21 sensors selected by the simulated annealing algorithm, could correctly classify 100 % of the water samples (leave-one out cross-validation). This potential was further demonstrated by applying a repeated K-fold cross-validation (guaranteeing that at least 15 % of independent samples were only used for internal-validation) for which 96 % of correct classifications were attained. The satisfactory recognition performance of the E-tongue could be attributed to the pH, conductivity, sugars and organic acids contents of the studied waters, which turned out in significant differences of sweetness perception indexes and total acid flavor. Moreover, the E-tongue combined with multivariate linear regression models, based on sub-sets of sensors selected by the simulated annealing algorithm, could accurately estimate waters pH (25 sensors: R 2 equal to 0.99 and 0.97 for leave-one-out or repeated K-folds cross-validation) and conductivity (23 sensors: R 2 equal to 0.997 and 0.99 for leave-one-out or repeated K-folds cross-validation). So, the overall satisfactory results achieved, allow envisaging a potential future application of electronic tongue devices for bottled water analysis and classification.This study was supported by Fundação para a CiĂȘncia e Tecnologia (FCT) and the European Community fund FEDER, under the Program PT2020 (Project UID/EQU/50020/2013) and under the strategic funding of UID/BIO/04469/2013 unit
Dietary sugars analysis: quantification of fructooligossacharides during fermentation by HPLC-RI method
In this work, a simple chromatographic method is proposed and in-house validated for the quantification of total and individual fructooligossacharides (e.g., 1-kestose, nystose, and 1F-fructofuranosylnystose). It was shown that a high-performance liquid chromatography with refractive index detector could be used to monitor the dynamic of fructooligossacharides production via sucrose fermentation using Aspergillus aculeatus. This analytical technique may be easily implemented at laboratorial or industrial scale for fructooligossacharides mass-production monitoring allowing also controlling the main substrate (sucrose) and the secondary by-products (glucose and fructose). The proposed chromatographic method had a satisfactory intra- and inter-day variability (in general, with a relative standard deviation lower than 5%), high sensitivity for each sugar (usually, with a relative error lower than 5%), and low detection (lower than 0.06â±â0.04âg/L) and quantification (lower than 0.2â±â0.1âg/L) limits. The correct quantification of fructooligossacharides in fermentative media may allow a more precise nutritional formulation of new functional foods, since it is reported that different fructooligossacharides exhibit different biological activities and effects.This work was partially co-financed by FCT and FEDER under
Program COMPETE (Project PEst-C/EQB/LA0020/2013), by
the Strategic Project PEst-OE/EQB/LA0023/2013 and by the
project ref. RECI/BBB-EBI/0179/2012 (project number FCOMP 01-0124-FEDER-027462) funded by Fundação para a CiĂȘncia e a
Tecnologia
Electrochemical multi-sensors device coupled with heuristic or meta-heuristic selection algorithms for single-cultivar olive oil classification
Potentiometric electrochemical multi-sensors performance highly depends on the capability of selecting the best set of sensors. Indeed, signals are usually collinear resulting in over-fitted multivariate models with low predictive applicability. In this work, a comparative study was made to evaluate the predictive performance of classification models coupled with heuristic or meta-heuristic variable selection algorithms. In this study, eleven single cultivar extra virgin olive oils, from two crop years, were used. The results demonstrated that linear discriminant analysis with simulated annealing algorithm allowed selecting the best subset of sensors enabling 100% of correct cross validation classifications, considering samples split by crop year
Sensory intensity assessment of olive oils using an electronic tongue
Olive oils may be commercialized as intense, medium or light, according to the intensity perception of fruitiness, bitterness and pungency attributes, assessed by a sensory panel. In this work, the capability of an electronic tongue to correctly classify olive oils according to the sensory intensity perception levels was evaluated. Cross-sensitivity and non-specific lipid polymeric membranes were used as sensors. The sensor device was firstly tested using quinine monohydrochloride standard solutions. Mean sensitivities of 14±2 to 25±6 mV/decade, depending on the type of plasticizer used in the lipid membranes, were obtained showing the device capability for evaluating bitterness. Then, linear discriminant models based on sub-sets of sensors, selected by a meta-heuristic simulated annealing algorithm, were established enabling to correctly classify 91% of olive oils according to their intensity sensory grade (leave-one-out cross-validation procedure). This capability was further evaluated using a repeated K-fold cross-validation procedure, showing that the electronic tongue allowed an average correct classification of 80% of the olive oils used for internal-validation. So, the electronic tongue can be seen as a taste sensor, allowing differentiating olive oils with different sensory intensities, and could be used as a preliminary, complementary and practical tool for panelists during olive oil sensory analysis.This study was supported by Fundação para a CiĂȘncia e a Tecnologia (FCT),Portugal and the European Community fund FEDER, under the Program PT2020 (Project UID/EQU/50020/2013); under
the strategic funding of UID/BIO/04469/2013 unit; and by Project POCTEP through Project RED/AGROTEC â Experimentation network and transfer for development of agricultural and agroindustrial sectors between Spain and Portugal
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