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- Spectral measurement of an arquiled arquicity R1 LED streetlight installed at Cumeada, dark sky AlquevaPublication . Lima, Raul Cerveira; Bará, SalvadorDuring late 2016 the national Portuguese electricity operator, Electricidade de Portugal (EDP), changed the streetlights of the hamlet of Cumeada, Reguengos de Monsaraz, Évora, to white light emission diodes technology (LED). The hamlet of Cumeada is within the borders of the Starlight Tourism Destination Dark Sky Alqueva (DSA). We evaluated in lab the spectrum and the CCT of one of those LED. The results revealed the LED luminaires installed in the hamlet are not appropriate for use in a dark skies reserve.
- An easy procedure for calibrating data acquisition systems using interleavingPublication . Clemêncio, Filomena; Loureiro, Custódio F. M.; Correia, Carlos M. B. A.Interleaving data acquisition channels is a well-known and interesting technique to achieve higher acquisition rates. However, to obtain the expected benefits, a careful look at the interleaving technique and to mismatches that can lead to unwanted harmonic distortion and noise is essential. In this paper we discuss the methods used to interleave existing high-speed, 250 MSPS 8-bit acquisition channels, and the results obtained. The methods presented allowed a good relative channel calibration in amplitude (amplitude mismatch under 0.1 lsb) and in time (time mismatch between acquisition channels in the ps range, under the specified maximum jitter for the ADC used). A dynamic, by software, amplitude level signal-dependent adjustment procedure is also suggested for signals with rich frequency content that can substantially improve the quality of the acquired signal when using interleaved channels. The techniques presented provide good results even in the presence of noise.
- Outdoor systems performance and upgradePublication . Lopes, L.; Andringa, S.; Assis, P.; Blanco, A.; Carolino, N.; Cerda, M.A.; Clemêncio, Filomena; Conceição, R.; Cunha, O.; Dobrigkeit, C.; Ferreira, M.; Loureiro, C.; Mendes, L.; Nogueira, J.C.; Pereira, A.; Pimenta, M.; Saraiva, J.; Sarmento, R.; Teixeira, P.; Tomé, B.Over the last two decades, the possibility of using RPCs in outdoors systems has increased considerably. Our group has participated in this effort by installing several systems and continues to work on their optimization, while simultaneously studying and developing new approaches that can use RPCs in outdoor applications. In particular, four detectors were deployed in the field at the Pierre Auger Observatory in 2019 remained inactive, awaiting the commissioning of support systems. During the pandemic the detectors were left without gas flow for more thantwo years, but were recently reactivated with no major problems. The Lou Mu project combines particle physics and geophysics in order tomapmeter-scale geologic structures, using Muon Tomography. Transmission muography is sensitive to the total amount of matter crossed by the muons, allowing to separate targets of different densities. In this exploratory project, it serves to identify unconsolidated rockzones, like geological faults and ore masses around an old Pyritemine,now converted into a science center. The general goal is to compare how effective is the muographic survey when compared with the more standard geophysical techniques. The development of the RPC system used and the data from the last two years will be presented. Finally, recent advances in a large area(1m2) doubl egap-sealed RPC will be presented.
- Quantifying the visual impact of wind farm lights on the nocturnal landscapePublication . Bará, Salvador; C. Lima, RaúlWind farm lights are a conspicuous feature in the nocturnal landscape. Their presence is a source of light pollution for residents and the environment, severely disrupting in some places the aesthetic, cultural, and scientific values of the pristine starry skies. In this work we present a simple model for quantifying the visual impact of individual wind turbine lights, based on the comparison of their brightness with the brightness of well- known night sky objects. The model includes atmospheric and visual variables, and for typical parameters it shows that medium-intensity turbine lights can be brighter than Venus up to ~4 km from the turbine, brighter than CMa (the brightest star on the nighttime sky) until about ~10 km, and reach the standard stellar visibility limit for the unaided eye (m v =+6.00) at ~38 km. These results suggest that the visual range of wind farms at nighttime may be significantly larger than at daytime, a factor that should be taken into account in environmental impact assessments.
- Acupuncture effect on reaction-time changes in Parkinson’s disease patients—Case study seriesPublication . Pereira, Catarina Ramos; Greten, Henry J.; Santos, Rubim; Reis, Ana Mafalda; Ramos, Bruno; Santos, Maria João; Machado, Jorge; Criado, Maria BegoñaParkinson’s Disease (PD) is a progressive neurodegenerative condition associated with deficit in reaction time which can lead to falls, resulting in limited independence, diminished quality of life, heightened rates of institutionalization and increased healthcare costs. We aimed to examine the effects of an acupuncture protocol in motor time response after an auditory stimulus. Methods: This study employed a case series design. Reaction time to exposed rhythmic and random auditory stimuli outcomes were evaluated at six different moments over a month-long acupuncture treatment protocol using the MP 36 system from Biopac Systems. Results: We observed a tendency to have more pronounced improvements in the time response in the more affected side of the body compared with the contralateral one. Patients tended to show better values of response to random auditory stimuli compared to rhythmic auditory ones. We also observed a tendency to obtain better results when considering the accumulative effects of the acupuncture protocol. Conclusions: Our findings indicated a possible role of reaction time as a sensitive and useful tool for motor function assessment in PD patients. Also, from our results, we concluded that the acupuncture protocol used may lead to an improvement in efficacy of motor response after aleatory and rhythmic stimulus; we also found a tendency for a higher efficacy of acupuncture in random stimuli responses in the first stages of the disease. However, further in-depth research, including a statistical evaluation with a larger participant pool, is necessary to validate and confirm these promising results.
- Antagonist coactivation of muscles of ankle and thigh in post-stroke vs. healthy subjects during sit-to-stand taskPublication . Pinho, Liliana; Sousa, Andreia S. P.; Silva, Cláudia; Cunha, Christine; Santos, Rubim; Tavares, João Manuel R. S.; Pereira, Soraia; Pinheiro, Ana Rita; Félix, José; Pinho, Francisco; Sousa, Filipa; Silva, AugustaThis study aims to analyse the coactivation of antagonist muscles of the thigh and ankle during the sit-to-stand task in post-stroke subjects, specifically during forward and antigravity sub-phases. A group of 18 healthy subjects and another with 18 subjects with a history of stroke participated voluntarily in this study. Bilateral surface electromyography (EMGs) of the soleus, gastrocnemius medialis, tibialis anterior, rectus femoris and biceps femoris muscles were collected synchronously with ground reaction forces (GRF) during the sit-to-stand task. The magnitude of electromyographic (EMG) activity was analysed during forward translation and antigravity sub-phases which were determined through GRF signals. The coactivation was calculated to quantify the degree of antagonist coactivation according to the role of the muscles during the task. Statistically significant values were found between antagonist coactivation on both sub-phases of the sit-to-stand task when comparing healthy and post-stroke subjects (healthy with ipsilesional (IPSI); healthy with contralesional (CONTRA); and healthy with IPSI and with CONTRA limbs) in all muscle pairs analysed (p < 0.01), except on thigh muscles (p > 0.05), in the antigravity sub-phase. When comparing IPSI with CONTRA sides in post-stroke subjects, no statistically significant differences were found. Increased values of antagonist coactivation were observed in post-stroke subjects compared to healthy subjects (both IPSI and CONTRA limb) in the two sub-phases analysed. The forward sub-phase CONTRA limb showed higher antagonist coactivation compared to IPSI, while in the antigravity sub-phase, IPSI antagonist coactivation was higher than in the CONTRA. In conclusion, post-stroke subjects presented an antagonist coactivation more dysfunctional at the ankle joint muscles compared to the thigh segment. So, it seems that the distal segment could express more accurately the central nervous system dysfunction in post-stroke subjects, despite the need for further studies to achieve a better spatiotemporal understanding of the variability on coactivation levels.
- Unlocking the potential: Increasing muscle strength in lower limbs of youth soccer players over five weeks through mat pilates training—A pilot studyPublication . Parolini, Franciele; Bertolini, Gladson; Santos, Rubim; Abreu, Manoela; Nogueira, Ana Laura; Bertoncello, DernivalThe interest in soccer generally starts during childhood, with children and young people often looking for opportunities in sports. New exercise techniques can be effective in improving training. The aim of this study was to compare the effects on the strength and physical posture of a group practicing Pilates with another not practicing Pilates, both undergoing continuous football training. In this controlled randomized clinical trial, the participants were 15 soccer club members, who had a training frequency of least three times weekly. The sample was divided into a control group (n = 7) of players who did not undergo any therapeutic intervention (only the usual training) and a Pilates group (n = 8) of players who participated in the mat Pilates program. The intervention consisted of fifteen sessions. Postural evaluations were performed using biophotogrammetry and force analysis. Significant improvements were obtained in terms of increased muscle strength (p = 0.001) for the Pilates group, but there were no significant postural alterations when comparing the two groups. Five weeks of mat Pilates was sufficient to increase lower limb muscle strength in young football players. This pilot study indicates that Mat Pilates as a method that could be planned to be included in training.
- Physical activity, readiness, and cardiovascular risk stratification in the polytechnics communities of the northern region of portugal integrated in mobility as a service conceptPublication . Sousa, Andreia; Guedes, Diana C.; Félix, José; Pereira, Soraia; Santos, RubimThe aim of the study is to characterize physical activity (PA) levels and PA readiness as well as stratify cardiovascular risk among the population of polytechnics community members in the north region of Portugal, including students, academic teachers, and non-teacher staff. An online questionnaire about general sample characterization, PA level, and readiness was applied. Of the 717 respondents, 237 were academic teachers, 143 were non-teacher staff, and 337 were students. Most of the participants had a level of moderate PA, including students, academic teachers, and non-teacher staff (82%). The sedentary behavior was higher in the academic teachers and non-teacher staff groups. A total of 56% of the participants had low cardiovascular risk; the group of students were the population with higher risk. Approximately half of the participants need to consult a qualified professional before increasing their PA. Overall, the participants presented moderate levels of PA, although there is still a considerable number of sedentary people that must be considered.
- Breaking barriers: Artificial intelligence interpreting the interplay between mental illness and pain as defined by the International Association for the Study of PainPublication . Parolini, Franciele; Goethel, Márcio; Becker, Klaus; Fernandes, Cristofthe; Fernandes, Ricardo J.; Ervilha, Ulysses F.; Santos, Rubim; Vilas-Boas, João PauloLow back pain is one of the main causes of motor disabilities and psychological stress, with the painful process encompassing sensory and affective components. Noxious stimuli originate on the periphery; however, the stimuli are recombined in the brain and therefore processed differently due to the emotional environment. To better understand this process, our objective was to develop a mathematical representation of the International Association for the Study of Pain (IASP) model of pain, covering the multidimensional representation of this phenomenon. Data from the Oswestry disability index; the short form of the depression, anxiety, and stress scale; and pain catastrophizing daily questionnaires were collected through online completion, available from 8 June 2022, to 8 April 2023 (1021 cases). Using the information collected, an artificial neural network structure was trained (based on anomaly detection methods) to identify the patterns that emerge from the relationship between the variables. The developed model proved to be robust and able to show the patterns and the relationship between the variables, and it allowed for differentiating the groups with altered patterns in the context of low back pain. The distinct groups all behave according to the main finding that psychological and pain events are directly associated. We conclude that our proposal is effective as it is able to test and confirm the definition of the IASP for the study of pain. Here we show that the fiscal and mental dimensions of pain are directly associated, meaning that mental illness can be an enhancer of pain episodes and functionality.
- Interlimb coordination during double support phase of gait in people with and without strokePublication . Couto, Ana G. B.; Vaz, Mário A. P.; Pinho, Liliana; Félix, José; Moreira, Juliana; Pinho, Francisco; Mesquita, Inês; Mesquita Montes, António; Crasto, Carlos; Sousa, AndreiaThis study aims to identify differences between participants with and without stroke regarding the ipsilesional and contralesional lower limbs kinematics, kinetics, muscle activity and their variability during double support phase of gait. Eleven post-stroke and thirteen healthy participants performed 10 gait trials at a self-selected speed while being monitored by an optoelectronic motion capture system, two force plates and an electromyographic system. The following outcomes were evaluated during the double support: the time and the joint position; the external mechanical work on the centre of mass; and the relative electromyographic activity. Both, contralesional/ipsilesional and dominant/non-dominant of participants with and without stroke, respectively, were evaluated during double support phase of gait in trailing or leading positions. The average value of each parameter and the coefficient of variation of the 10 trials were analysed. Post-stroke participants present bilateral decreased mechanical work on the centre of mass and increased variability, decreased contralesional knee and ankle flexion in trailing position, increased ipsilesional knee flexion in leading position and increased variability. Increased relative muscle activity was observed in post-stroke participants with decreased variability. Mechanical work on the centre of mass seems to be the most relevant parameter to identify interlimb coordination impairments in post-stroke subjects.