1,720,962 research outputs found
Comparison of Kinematic Parameters Between Young and Elderly Subjects in Some Tinetti Tasks
No full textThe Tinetti Mobility test (or POMA test) is the most used scale to assess fall risk in an ambulatory setting or hospice. The scale consists of scored tasks about balance and gait and the sum of the scores defines the level of risk (a total of 28 for the lower risk level). In this preliminary study, we involved 28 young subjects and 24 elderly people divided according to the Tinetti score into High Risk (≤ 18) and Low Risk (> 18) groups. A wireless 3D magneto inertial sensor placed on the chest of the subjects was used to acquire kinematic characteristics of movement and compare them between young and elderly groups during the execution of three tasks belonging to the Tinetti scale: arising from a chair, standing balance with open and closed eyes in Romberg position. The parameters evaluated for the first task were the duration of the movement and the maximum angular amplitude along the three directions, while for the other two tasks were the Spectral Power, the Variance, the Fractal Dimension, the Approximated Entropy, the Correlation Dimension, and the largest Lyapunov Exponent. Some significant differences were found between the Young group and both High Risk and Low-Risk groups in all three tasks. However, the low number of participants and the high inter-subjects variability did not allow for highlighting any significant difference between High Risk and Low-Risk groups. Finally, the standing balance tasks seem to be the most sensitive exercise to highlight differences between the groups
Kinematic Characterization of Movements During the Tinetti Test
No full textThe improvement in life expectancy has led to a corresponding increase in people suffering from chronic illnesses as well as in subjects at high risk of falling. Various scales exist in literature to evaluate fall risk in ambulatory settings among which the Tinetti Test is the most used. However, only trained healthcare professionals can conduct this test. In order to make this scale available to a growing number of older people outside hospital and to reduce the high inter operator bias in scoring the exercises, a less provider dependent system is necessary. In this preliminary study, which can be used as a benchmark for future evaluation of individuals at risk of falling, some parameters were extracted from a wireless 3D magnetic inertial sensor applied on the chest of 30 young healthy participants. Each subject performed four exercises from the Tinetti balance test: arising from a chair (1), standing balance with open (2), and closed eyes (3) and sitting down (4). For exercises (1) and (4), the duration of movement and the maximum angular amplitude were calculated, while for exercises (2) and (3) the fractal dimension and the spectral power were evaluated. The obtained values, directly correlated with the exercises, showed a low variability among subjects, resulting as potential candidates for the characterization of the movement during the Tinetti test, enabling non-expert operators to assess the falling risk
Influence of Fatigue in Swimmers Suffering from Swimmer Shoulder Pain
Full text linkThe shoulder joint is susceptible to be damaged in sports with overhead actions, often leading to swimmer shoulder pathology. Fatigue can also worsen and increase the risk of overuse injuries. Evaluating shoulder kinematics during swimming is crucial to identify injury-related movement patterns and to provide a correct physiotherapy treatment. To measure kinematics, inertial and magnetic measurement systems (IMMSs) offer a very versatile approach with respect to traditional video-based systems. This preliminary study focuses on the effects of fatigue on shoulder joint kinematics in swimmer with swimmer shoulder compared to healthy swimmers, by using IMMS. 11 young swimmers (5 pathological, 7 male) took part in the study. Each participant executed 40 s of dry front crawl followed by a fatiguing protocol and by other 40 s of dry front crawl. We analyze the arm movement relative to the thorax examining the differences of the movement amplitudes between healthy and pathological subjects and before and after fatigue exercise according to the three rotations: Flexion/Extension, Abduction/Adduction, and Internal/External rotation. Some slight non-significant differences were found after exercise compared to before in all the three rotations while a significant difference between healthy and pathological subjects was found in Flexion/Extension rotation both before and after fatigue exercise. The use of IMMS allowed to verify the repeatability of the kinematic movement and to quantify the rotation angles identifying which component of the movement is most affected by the swimmer shoulder pathology. However, a larger number of subjects is necessary in order to confirm the results. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
Relationship Between Personality and Kinematic Parameters of Handwriting
Full text linkMotor and cognitive systems are largely involved in producing handwriting that develops with age becoming more and more personalized until it reaches a style proper to the subject. This fact has led graphologists to assert that by examining the handwriting it is possible to somehow trace the personality of the writer. Many studies have been carried out to demonstrate this assumption but they are all based on the graphic examination of the tract left on the sheet of paper. On the other hand, recently it has been possible to examine writing through the use of digital tablets capable of providing information also on the kinematic of the movement, extracting parameters used to examine in particular dysgraphia and some neurological pathologies. Aim of this study was to determine possible relationships between kinematic parameters extracted using digital tablets and personality
traits. Sixty-one subjects took part in the study, executing three writing tasks (fast and accurate writing of an Italian phrase and fast sequence of cursive lowercase letters “lelele” without pen lifting for 30 s) and a personality test (IPIP-NEO-120). The linear regression between each of fourteen characteristic of handwriting and each of the five personality traits was computed. The results showed that four out of five main psychological tracts presented a linear relation with one or more kinematic characteristics. This study offers a first glance at a complex series of correlations, which will be investigated in future researches
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Shoulder tensiomyography and isometric strength in swimmers before and after a fatiguing protocol
Full text linkContext.
Shoulder muscles are active during front crawl swimming to provide propulsion and stabilize the glenohumeral and scapulothoracic joints. It has been proposed that fatigue might contribute to altered activation of these muscles and represent a risk factor for injuries. Tensiomyography (TMG) might represent a non-invasive tool to detect exercise-induced neuromuscular fatigue changes in contractile parameters of the skeletal muscles, and it has never been used in the shoulder muscles in swimmers.
Objective.
The aim of this study was to assess the effects of a fatiguing swimming protocol on shoulder muscles TMG parameters and isometric strength in competitive swimmers.
Design.
A cross-sectional study.
Setting.
A swimming pool facility.
Patients or Other Participants.
Sixteen young front crawl competitive swimmers were invited to participate in the study, and 14 of them (21 y, range 17-26, 11 males 3 females) completed all the assessments before and after a 30-min high-intensity swimming training.
Main Outcome Measure(s).
The main outcome included the TMG assessment which was performed on seven muscles of the shoulder according to front crawl biomechanics and applicability of the technique, in order to obtain data such as time to contraction and muscle belly radial displacement (Dm), whereas isometric strength was assessed with a digital dynamometer during shoulder flexion, extension, external rotation and internal rotation.
Results.
Fatigue induced a smaller Dm (-0.5 mm, 95% CI: -0.7 - -0.3, p< 0.001, pη2= 0.692), mostly observable in latissimus dorsi and pectoralis major muscles. Only shoulder extension showed a significant isometric strength reduction after the fatiguing protocol (-0.03 N/kg, 95% CI: -0.05 - -0.01, p= 0.045, pη2= 0.275).
Conclusions.
This study provides preliminary evidence for the usefulness of TMG to detect fatigue-induced changes in contractile properties of the shoulder muscles in swimmers, in particular the latissimus dorsi, pectoralis major and lower trapezius
Trade-Off Between Real-Time and Classification Performance in Motor Imagery BCI
No full textBrain-Computer Interfaces (BCIs) offer direct communication between the brain and external devices, holding immense potential across various applications. This study focuses on Motor Imagery-based BCIs (MI-BCI), decod- ing neural patterns associated with mentally rehearsed motor actions. Despite their promise, BCIs face challenges in real-world applications, primarily in reliability and complexity. While classification accuracy is a standard metric for BCI perfor- mance, the literature often overlooks real-time responsiveness. Many studies report classification outcomes offline, disregarding the prompt translation of EEG signals into actions. The acceptable delay from EEG signal to action should not exceed 1 s; however, numerous studies employ time-windows exceeding 4 s, affecting user control perception. This article aims to compare the trade-off between time- window length and classification accuracy in MI-BCI, using three linear classifiers (LDA, MLP, SVM). Participants include stroke patients and subjects from the BCI IVa dataset. Results demonstrate time-frequency plots indicating MI-related EEG changes, revealing a trade-off between accuracy and responsiveness. Our find- ings underscores the importance of addressing real-time responsiveness in BCI evaluations, proposing a balance for practical system utility. In conclusion, this study enhances our understanding of the delicate balance needed for optimal real- world application of MI-BCIs, emphasizing the trade-off between accuracy and responsiveness
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