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- Principal component analysis of stair negotiation and floor transition kinematics in older adults with and without functional disability: cross-sectional studyPublication . Moreira, Juliana; Teles, Ivone da Silva; Cunha, Bruno; Félix, José; Guedes, Diana C.; Alves, Leonel A. T.; Santos, Rubim; Sousa, Andreia S P; Pinheiro de Sousa, Andreia Sofia; Rubim Silva Santos, Manuel; Santos Moreira, Juliana; Sousa Félix, José ManuelStair negotiation (ascending and descending) and transitions to level walking are complex motor tasks influenced by aging; yet the impact of functional disability on these changes remains underexplored. This study aimed to evaluate the lower limb joint positions, velocities, and the center of mass (CoM) displacement and velocity during stair negotiation and transitions in older adults with and without functional disability. Sixty community-dwelling adults, aged 60 years and older, were assessed for lower limb tridimensional joint positions and velocities during the instances of foot contact or leaving the step and foot contact or leaving the floor; the joint range of motion, angular velocity range, and the CoM displacement and angular velocity range were assessed during stair ascend and descend and transitions floor-to-stair and stair-to-floor through an optoelectronic system. Principal component analysis was used to assess 8 groups of variables to compute principal component models (I-VIII). Participants were classified as with or without disability based on functional disability indicators. Group differences were assessed using the Mann-Whitney U test. From 240 variables, 41 key parameters were identified, mainly related to hip and knee angular velocities in the sagittal plane. Significant differences between older adults with disability (n=25) and without disability (n=35) were found in 12 principal components. Older adults with functional disability showed changes in the sagittal plane hip as well as in the knee angular velocity and mediolateral and vertical CoM displacement and velocity during stair negotiation and transitions. These findings can inform targeted strategies to improve mobility and stability in this population.
- Kinematic and Kinetic gait principal component domains in older adults with and without functional disability: a cross-sectional studyPublication . Moreira, Juliana; Cunha, Bruno; Félix, José; Santos, Rubim; Sousa, Andreia S. P.; Pinheiro de Sousa, Andreia Sofia; Rubim Silva Santos, Manuel; Santos Moreira, Juliana; Sousa Félix, José ManuelGait kinematic and kinetic changes have been identified in older adults, highlighting the need to explore the principal age-related components and how these are associated with functional disability. This study aims to perform a factor analysis, including gait kinematic and kinetic parameters in older adults to establish determinant gait domains. Additionally, this study aims to identify which domains differentiate those without and with functional disability. Through a cross-sectional design, older adults aged 60 and over (n = 35 without and n = 25 with functional disability) were analyzed during overground gait. A principal component analysis (PCA) was used to determine principal components from gait parameters previously demonstrated to express age-related effects (spatiotemporal parameters, sagittal ankle moment and power, ground reaction forces peak, and tridimensional lower limb joints range of motion and positions at heel strike and toe-off). Pace, variability, propulsion, hip and knee control, transverse ankle control, asymmetry, sagittal ankle control, frontal ankle control, frontal hip control, and pre-swing control domains explained 83.90% of the total gait variance in older adults. pace and frontal hip control distinguished individuals with disabilities. PCA identified ten gait domains in older adults. Pace and frontal hip control distinguished disabilities, revealing cautious walking patterns and weaker hip abductor strength.
- Analysis of patellar reflex in Parkinson disease patients after an acupuncture treatment protocol – Case series studyPublication . Pereira, Catarina Ramos; Reis, Ana Mafalda; Machado, Jorge; Ramos, Bruno; Criado, Begona; Santos, Maria João; Santos, Rubim; Greten, Henry Johannes; Rubim Silva Santos, ManuelThe investigation of rigidity physiology in Parkinson’s Disease involves the examination of reflexes. Parkinsonian patients often demonstrate reduced sensitivity in polysynaptic reflexes within the leg extensor muscles, which is correlated with their postural instability. The compensatory mechanisms for impaired proprioceptive reflex function may involve alterations in intrinsic muscle stiffness. The interplay between gait and reflexes is intricately linked to the nervous system’s functioning and motor control. Certain reflexes, such as patellar reflex, play a pivotal role in maintaining walking and posture. Ensuring the integrity of these reflexes is essential for facilitating smooth and efficient walking. To analyze the behavior of patellar reflex in four Parkinson’s Disease patients undergoing an acupuncture treatment protocol. This study adopts a case series design. Reflex outcomes based on amplitude and velocity were assessed at six different time moments throughout a month-long treatment protocol using the MP 36, Biopac Systems. Over the long term, a tendency for an improvement in range of movement and velocity of the patellar reflex, was observed. Nevertheless, in specific cases, a reduction in the amplitude during acute effects was also found. Our findings suggest that the acupuncture protocol used may lead to a cumulative improvement in efficacy of patellar reflex in patients with Parkinson’s disease. However, further in-depth research, including a statistical evaluation with a larger participant pool, is necessary to validate and confirm these promising preliminary results.
- Beyond low back pain! The influence of physical activity on mental health, reflected in the functionality of people with low back painPublication . Parolini, Franciele; Becker, Klaus; Goethel, Márcio; Fernandes, Ricardo J.; Fonseca, Hélder; Ervilha, Ulysses F.; Vilas-Boas, João Paulo; Santos, RubimPsychological factors play a crucial role in the experience of acute low back pain and may influence functional outcomes. However, the interplay between these factors and levels of physical activity remains poorly understood. This cross-sectional observational study examined the relationship between psychological variables and functional disability in individuals with acute low back pain, considering different levels of physical activity. Data were collected from 1021 participants through an online platform between 8 June 2022 and 8 April 2023. Standardized instruments were used to assess functional limitations, emotional distress (depression, anxiety, and stress), daily pain catastrophizing, and physical activity levels. A canonical correlation analysis was conducted to explore the multivariate associations between psychological and functional variables. There was a statistically significant association between higher levels of emotional distress and greater functional impairment related to low back pain. This association was observed in both the light-physical-activity group (canonical coefficient = 0.266; p = 0.017), the moderate-physical-activity group (0.237; p = 0.092), and the vigorous-physical-activity group (0.177; p = 0.013). Participants engaging in vigorous physical activity exhibited more favorable psychological profiles and lower functional disability compared to those with lower levels of activity. Regular and vigorous physical activity appears to be a protective factor for mental health and may help reduce functional disability in individuals with acute low back pain. These findings underscore the importance of considering physical activity levels when addressing psychological and functional outcomes in this population.
- Cochlear hair cell regeneration based on stem cells: A systematic reviewPublication . Costa, Vítor Bruno; Tomé, David; Çirtlik, Zeynep Yağmur; Öztürk, Yaren; Clemêncio, Filomena; Pitt-Byrne, Theresa; Tomé, David; Costa Clemêncio, Filomena MariaAccording to the World Health Organization (WHO), by 2050 at least 700 million people will need access to hearing care and hearing rehabilitation services. The search for cell or gene therapies has been intensifying, and stem cell therapy looks a promising candidate to support hearing regeneration and reduce these numbers. The aim of this study is to provide an overview of current advances in stem cellbased therapies for cochlear hair cell regeneration and the processes being developed for future applicability. Identification and review of all articles in the databases PubMed, Web of Science, and PLoS One using the terms stem cell, auditory hair cell regeneration, and mammalian during February 2023 and following the PRISMA guidelines. 50 articles were obtained, published between 2003 and 2022 and were systematically analyzed. The current research quantity is limited and further studies are needed, particularly in human tissue. The simultaneous use of cell therapy and gene therapy may lead to more promising results. Moreover, advances in cochlear hair cell regeneration with stem cells suggest there is a realistic potential to make the technique a useful future therapy.
- Precision and reliability of a dynamometer for trunk extension strength and steadiness assessmentPublication . Parolini, Franciele; Goethel, Márcio; Robalino, Johan; Becker, Klaus; Sousa, Manoela; Pulcineli, Barbara C.; Ervilha, Ulysses F.; Vilas-Boas, João Paulo; Santos, Rubim; Rubim Silva Santos, Manuel; Carvalho Santos Parolini, FrancieleLow back pain is a major cause of disability worldwide, often associated with deficits in trunk extensor strength control. Accurate assessment of trunk extension strength control is crucial for diagnosing impairments and monitoring interventions. This study evaluated the reliability of a dynamometry-based protocol for isometric trunk extension strength control assessment. Twenty-eight healthy volunteers (9 females, 19 males) completed two sessions, seven days apart. A single-point load cell system, encapsulated within a 3D-printed structure and connected to a Delsys system® at a sampling frequency of 2000 Hz, was used for data acquisition. Participants performed maximal voluntary contractions (MVC) and submaximal isometric contractions (SMVC) guided by trapezoidal visual feedback. Key outcome variables included peak force, mean force, and force steadiness. Calibration demonstrated high accuracy (R2 = 1) with a low root mean square error (0.55 N). Test–retest analysis showed excellent reliability for peak force (ICC = 0.81, SEM = 0.50, MDC = 1.39), mean force (ICC = 0.93, SEM = 0.17, MDC = 1.08), and steadiness (ICC = 0.87, SEM = 0.85, MDC = 2.36), with no significant intersession differences (p > 0.05). This study demonstrates the high reliability of using dynamometry to assess trunk extension strength during MVC and SMVC, endorsing the dynamometer as a tool for functional assessment and the development of personalized rehabilitation and training strategies.
- The influence of artificial breast volume induction on postural stability, postural orientation, and neuromuscular control in healthy women: a cross-sectional studyPublication . Guedes, Diana C.; Carneiro, Daniela Ferreira; Alves, Leonel Agostinho Teixeira; Melo, Ana S. C.; Moreira, Juliana; Cunha, Bruno; Santos, Rubim; Noites, Andreia; Sousa, Andreia S. P.; C. Guedes, Diana; Melo, Ana; Santos Moreira, Juliana; Cunha, Bruno; Rubim Silva Santos, Manuel; Noites, Andreia; Pinheiro de Sousa, Andreia SofiaThe percentage of breast augmentations has increased in recent years alongside the frequency of implant removals. Musculoskeletal and postural disorders are often overlooked during this removal process. Research indicates that excess anterior load from breast implants can disrupt postural control and potentially lead to short- or long-term musculoskeletal dysfunction. This study aims to evaluate the immediate changes in postural control after artificial breast augmentation in healthy female volunteers. Spinal angles, the center of pressure (CoP), and electromyographic activity of the spinal muscles were recorded in the static position and during the functional reach test (FRT) without and with implants of different volumes (220 mL, 315 mL, and 365 mL). Subjective perceptions of effort, comfort, weight, and performance in the FRT were also assessed. Statistical differences were significant in the scapular elevator during the one-minute standing position (lower activation with the 220 mL implant compared to the control and 315 mL) and in the trapezius muscles during the FRT (lower activation in the upper trapezius in the 315 mL vs. control in the reach phase and 220 mL vs. control in the return phase and higher activation in the lower trapezius in the 315 and 365 mL vs. control in the reach phase). Additionally, significant differences were identified in the performance of the FRT and the associated subjective perceptions. Breast implants with sizes of 220, 315, and 365 mL can alter scapular neuromuscular control, but these differences do not seem substantial enough to result in negative biomechanical effects in the short-term analysis.
- 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.