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1.
J Affect Disord ; 351: 746-754, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38290589

RESUMO

BACKGROUND: Prior studies on Prolonged Grief Disorder (PGD) primarily employed classical approaches to link bereaved individuals' characteristics with PGD symptom levels. This study utilized machine learning to identify key factors influencing PGD symptoms during the COVID-19 pandemic. METHODS: We analyzed data from 479 participants through an online survey, employing classical data exploration, predictive machine learning, and SHapley Additive exPlanations (SHAP) to determine key factors influencing PGD symptoms measured with the Traumatic Grief Inventory - Self Report (TGI-SR) from 19 variables, comparing five predictive models. RESULTS: The classical approach identified eight variables associated with a possible PGD (TGI-SR score ≥ 59): unexpected causes of death, living alone, seeking professional support, taking anxiety and/or depression medications, using more grief services (telephone or online supports) and more confrontation-oriented coping strategies, and higher levels of depression and anxiety. Using machine learning techniques, the CatBoost algorithm provided the best predictive model of the TGI-SR score (r2 = 0.6479). The three variables influencing the most the level of PGD symptoms were anxiety, and levels of avoidance and confrontation coping strategies used. CONCLUSIONS: This pioneering approach within the field of grief research enabled us to leverage the extensive dataset collected during the pandemic, facilitating a deeper comprehension of the predominant factors influencing the grieving process for individuals who experienced loss during this period. LIMITATIONS: This study acknowledges self-selection bias, limited sample diversity, and suggests further research is needed to fully understand the predictors of PGD symptoms.


Assuntos
Luto , COVID-19 , Transtornos de Estresse Pós-Traumáticos , Humanos , Pandemias , Transtorno do Luto Prolongado , Pesar , Inteligência Artificial , Transtornos de Estresse Pós-Traumáticos/epidemiologia
2.
Sensors (Basel) ; 22(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35458814

RESUMO

Several smart home architecture implementations have been proposed in the last decade. These architectures are mostly deployed in laboratories or inside real habitations built for research purposes to enable the use of ambient intelligence using a wide variety of sensors, actuators and machine learning algorithms. However, the major issues for most related smart home architectures are their price, proprietary hardware requirements and the need for highly specialized personnel to deploy such systems. To tackle these challenges, lighter forms of smart home architectures known as smart homes in a box (SHiB) have been proposed. While SHiB remain an encouraging first step towards lightweight yet affordable solutions, they still suffer from few drawbacks. Indeed, some of these kits lack hardware support for some technologies, and others do not include enough sensors and actuators to cover most smart homes' requirements. Thus, this paper introduces the LIARA Portable Smart Home Kit (LIPSHOK). It has been designed to provide an affordable SHiB solution that anyone is able to install in an existing home. Moreover, LIPSHOK is a generic kit that includes a total of four specialized sensor modules that were introduced independently, as our laboratory has been working on their development over the last few years. This paper first provides a summary of each of these modules and their respective benefits within a smart home context. Then, it mainly focus on the introduction of the LIPSHOK architecture that provides a framework to unify the use of the proposed sensors thanks to a common modular infrastructure capable of managing heterogeneous technologies. Finally, we compare our work to the existing SHiB kit solutions and outline that it offers a more affordable, extensible and scalable solution whose resources are distributed under an open-source license.


Assuntos
Algoritmos , Computadores , Tecnologia
3.
J Biomech ; 126: 110624, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34293599

RESUMO

The purpose was to specify the impact of two different forces exerted by vibratory devices on the Achilles tendon on postural balance. The postural balance of 13 participants was evaluated on a force platform in two 40 s bipedal stance conditions with closed eyes. Tendon vibrations (80 Hz) were triggered 10 s after the beginning of the postural evaluation and applied during 20 s. Two levels of the force exerted by the vibrators were calibrated using load cells to control the tightening parameters of the vibrators: a strong tightening (ST) condition at 45 N and a light tightening (LT) condition at 5 N. The soleus electromyographic (EMG) activity and the spatio-temporal parameters of displacement of the centre of foot pressure (COP) were analysed. To analyse the effects of the introduction, the adaptation and the end of the stimulation, non-parametric tests were used. The results indicated that the soleus EMG activity increased only in the ST condition. However, during the vibration the anteroposterior COP position was significantly more in a backward position in the LT condition. At the end of the vibration, COP parameters increased more in the LT condition than the ST condition. This study demonstrated that the effects of the vibration depended on the force exerted by the devices on the tendons. The ST increased the vibration effects on EMG activity through greater stimulating effects compared to the LT. However, the ST could also increase the ankle joint stiffness and/or somaesthetic sensory information, which attenuated the COP backward shift.


Assuntos
Tendão do Calcâneo , Propriocepção , Tornozelo , Humanos , Músculo Esquelético , Equilíbrio Postural , Vibração
4.
IEEE J Biomed Health Inform ; 25(4): 1273-1283, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33017299

RESUMO

Fall detection is a major challenge for researchers. Indeed, a fall can cause injuries such as femoral neck fracture, brain hemorrhage, or skin burns, leading to significant pain. However, in some cases, trauma caused by an undetected fall can get worse with the time and conducts to painful end of life or even death. One solution is to detect falls efficiently to alert somebody (e.g., nurses) as quickly as possible. To respond to this need, we propose to detect falls in a real apartment of 40 square meters by exploiting three ultra-wideband radars and a deep neural network model. The deep neural network is composed of a convolutional neural network stacked with a long-short term memory network and a fully connected neural network to identify falls. In other words, the problem addressed in this paper is a binary classification attempting to differentiate fall and non-fall events. As it can be noticed in real cases, the falls can have different forms. Hence, the data to train and test the classification model have been generated with falls (four types) simulated by 10 participants in three locations in the apartment. Finally, the train and test stages have been achieved according to three strategies, including the leave-one-subject-out method. This latter method allows for obtaining the performances of the proposed system in a generalization context. The results are very promising since we reach almost 90% of accuracy.


Assuntos
Redes Neurais de Computação , Humanos
5.
Motor Control ; 24(3): 383-396, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32413840

RESUMO

A cross-sectional, prospective, between-subjects design was used in this study to establish the differences in sensory reweighting of postural control among different ages during adolescence. A total of 153 adolescents (five age groups; 13-17 years old) performed bipedal standing in three sensory conditions (i.e., with visual restriction, vestibular disturbance, and proprioceptive disturbance). Center of pressure displacement signals were measured in mediolateral and anteroposterior directions to characterize reweighting in the sensory system in static postural control when sensory information is disturbed or restricted during adolescent growth. The results indicate a development of postural control, showing large differences between subjects of 13-14 years old and older adolescents. A critical change was found in sensory reweighting during bipedal stance with disturbance of proprioceptive information at 15 years old. Adolescents of 13-14 years old showed less postural control and performance than older adolescents during the disturbance of proprioceptive information. Moreover, the results demonstrated that the visual system achieves its development around 15-16 years old. In conclusion, this research suggests that a difference of sensory reweighting under this type of sensorial condition and sensory reweight systems would seem to achieve stabilization at the age of 15.


Assuntos
Equilíbrio Postural/fisiologia , Propriocepção/fisiologia , Posição Ortostática , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos
6.
Front Aging Neurosci ; 9: 167, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28611657

RESUMO

The aim of this study was to compare the ability of older individuals to maintain an efficient upright stance in contexts of vestibular sensory manipulation, according to their physical activity status. Two groups of healthy older women (aged over 65) free from any disorders (i.e., neurological, motor and metabolic disorders) and vestibular disturbances, participated in this study. One group comprised participants who regularly practiced gentle physical activities, i.e., soft gym, aquarobic, active walking, ballroom dancing (active group, age: 73.4 (5.8) years, n = 17), and one group comprised participants who did not practice physical activities (non-active group, age: 73.7 (8.1) years, n = 17). The postural control of the two groups was compared in a bipedal reference condition with their eyes open and two vestibular sensory manipulation conditions (i.e., bipolar binaural galvanic vestibular stimulation (GVS) at 3 mA, in accordance with two designs). The main results indicate that there was no difference between the active and the non-active groups in all the conditions. It is likely that the aging process and the type of physical practice had limited the ability of the active group to counteract the effects of vestibular sensory manipulation on postural control more efficiently than the non-active group.

7.
Artigo em Inglês | MEDLINE | ID: mdl-28539960

RESUMO

The self-controlled follow-up pilot study was set up to examine the maintenance of engagement in physical activity by a group of older adults in a thermal spa resort, as a consequence of the inclusion of additional physical education sessions within their usual care offers. A cohort of 42 participants (70.4 ± 4.5 years) underwent three weeks of thermal treatment with additional physical education (PE) sessions. Measurements were established during the intervention in 2 periods (baseline and final thermal treatment evaluation) and 4 periods of measurements in the follow-up (+15 days, +2 months, +6 months, and +1 year). Physical measures (anthropometrics, flexibility, and 6-minute walk test) and intrapersonal and psychosocial factors as well as health-related quality of life (HQOL) and physical activity (PA) were self-reported by participants. Only HQOL and PA were assessed during the follow-up. One year after a 3-week PE session combined with the usual thermal care, 64% of the participants exhibited a higher volume of PA than at baseline. The components of the HQOL changed during the follow-up. This strategy to maintain PA engagement appears to be feasible in a population of thermal care older adults. This work demonstrates the feasibility of a study conducted to maintain physical activity engagement after a thermal treatment.

8.
PLoS One ; 11(9): e0162966, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27627441

RESUMO

The purpose of this study was to compare the effects of galvanic vestibular stimulation (GVS) on postural control for participants of different physical activity status (i.e. active and non-active). Two groups of participants were recruited: one group of participants who regularly practised sports activities (active group, n = 17), and one group of participants who did not practise physical and/or sports activities (non-active group, n = 17). They were compared in a reference condition (i.e bipedal stance with eyes open) and four vestibular manipulation condition (i.e. GVS at 0.5 mA and 3 mA, in accordance with two designs) lasting 20 seconds. The centre of foot pressure displacement velocities were compared between the two groups. The main results indicate that the regular practice of sports activities counteracts postural control disruption caused by GVS. The active group demonstrated better postural control than the non-active group when subjected to higher vestibular manipulation. The active group may have developed their ability to reduce the influence of inaccurate vestibular signals. The active participants could identify the relevant sensory input, thought a better central integration, which enables them to switch faster between sensory inputs.


Assuntos
Exercício Físico/fisiologia , Postura/fisiologia , Vestíbulo do Labirinto/fisiologia , Atletas , Estudos de Casos e Controles , Estimulação Elétrica , Feminino , Humanos , Adulto Jovem
9.
Front Hum Neurosci ; 10: 409, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27582699

RESUMO

The aim was to compare the balance control adaptation to different supporting surfaces depending on the age and the physical activity status. The balance control of two groups of young (n = 17) and old (n = 17) participants who practiced regular physical activity (active groups) and two groups of young (n = 17) and old (n = 17) participants who did not practice physical activity (non-active groups) was compared on a firm surface and on a foam surface. The parameters of the center of foot pressure (COP) displacement were compared between the groups. The two older groups were more disturbed than the two younger groups when they stood on a foam surface and there was no difference between active and non-active groups. This result may be linked to the structural and functional involutions of the plantar cutaneous sole and foot that occur with age advancement. The participants' physical activity practice might be not specific enough to generate a more efficient postural adaption to the foam condition for the active groups than the non-active groups within their respective age groups.

10.
J Rehabil Res Dev ; 50(6): 811-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24203543

RESUMO

The purpose of this study was to compare the effects of proprioceptive disruption on postural control for participants of different ages according to their physical and/or sport activity levels. Two groups of young and old participants who practiced chronic physical and/or sport activities (young active [n = 17; average age 20.5 +/- 1.1 yr] and old active [n = 17; average age 74.0 +/- 3.8 yr]) and two groups of young and old participants who did not practice physical and/or sport activities (young sedentary [n = 17; average age 20.0 +/- 1.3 yr] and old sedentary [n = 17; average age 74.7 +/- 6.3 yr]) participated in the study. They were compared in a bipedal quiet stance reference condition and a bilateral Achilles tendon vibration condition. Center of foot pressure displacements and frequency analysis were compared between the groups. The results indicated that when proprioceptive information was disrupted, the postural control disturbance was more important for the old sedentary group than for the other groups. There were no differences between the old active group and the young sedentary group. Postural control was less altered for the young active group than for the other groups. Aging decreases the efficiency of postural control regardless of the assessment conditions. Physical and sport activities may compensate for the disturbing effects of proprioceptive perturbation through a better use of sensory information whatever the age of the participants.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Equilíbrio Postural/fisiologia , Propriocepção/fisiologia , Comportamento Sedentário , Esportes/fisiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Análise e Desempenho de Tarefas , Vibração , Adulto Jovem
11.
Eur J Appl Physiol ; 113(7): 1821-31, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23423303

RESUMO

The purpose of the study was to compare the effects of sensory manipulations on postural control for subjects of different ages. A young group of subjects (n = 17; 20.0 ± 1.3 years) and an old group of subjects (n = 17; 74.7 ± 6.3 years) were compared in 14 postural conditions [2 reference conditions and 12 sensory manipulation conditions: eyes closed, cervical collar, tendon vibration, electromyostimulation, galvanic vestibular stimulation (2 designs), foam surface] on a force platform. Spatio-temporal parameters of the center of foot pressure displacement were analyzed. When vestibular or proprioceptive afferences were manipulated, the old group was more disturbed than the young group. In addition, when myo-articular proprioceptive afferences were the only non-manipulated information source, the old group was also more disturbed than the young group. Hence, the inability to correctly interpret proprioceptive information and/or the impairment of myo-articular information would appear to be the major factor causing postural control deterioration. Moreover, concerning the vestibular system, it may be that aging alters the central integration of vestibular afferences. These results suggest that aging differently affects the functional ability of the different neural loops in postural control.


Assuntos
Equilíbrio Postural/fisiologia , Postura , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Rede Nervosa/fisiologia , Testes de Função Vestibular , Adulto Jovem
12.
J Strength Cond Res ; 27(5): 1378-83, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22796998

RESUMO

Voluntary and stimulated contractions are commonly used in sports training and rehabilitation, and it is well known that both these kinds of contractions generate central fatigue. However, to date, there is a lack of research on the comparison of the mechanisms by which these 2 exercises induce central disturbances. Central fatigue can be characterized by central activation failure during maximal voluntary contraction (MVC). Superimposition of an electrical stimulation onto MVC has been used to detect central activation failure. Completeness of activation has been quantified by the central activation ratio (CAR) = MVC/(MVC + stimulated force). The aim was not only to evaluate the CAR immediately after fatiguing voluntary (VOL) and stimulated (STIM) contractions but also to compare recovery duration over different time periods (prefatigue: PRE condition; immediate postfatigue: POST condition; after a 5-minute recovery: POST 5 condition; after a 30-minute recovery: POST 30 condition) (n = 18). Results showed that in the POST condition, the CAR is more affected for the VOL contractions than for the STIM contractions (p < 0.001). The CAR was affected for the STIM contractions only in the POST 5 condition (p < 0.05). In the POST 30 condition, the CAR was incomplete for the STIM contractions, whereas it was complete for the VOL contractions (p < 0.01). In conclusion, the VOL contractions alter the CAR more than the STIM contractions immediately after their completion. However, the effects of the STIM contractions on the CAR are delayed and prolonged.


Assuntos
Estimulação Elétrica , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Quadríceps/fisiologia , Estimulação Elétrica/métodos , Eletromiografia , Humanos , Masculino , Adulto Jovem
13.
Eur J Appl Physiol ; 112(5): 1881-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21922258

RESUMO

The aim of this work was to compare the effects of fatigue of the quadriceps femoris after fatiguing voluntary contractions (VOL) and fatiguing neuromuscular electrical stimulation (ES) on bipedal postural control. Nineteen active male subjects (22.2 ± 1.7 years) completed these two fatiguing exercises. Isometric maximal voluntary contraction (MVC) and postural control were recorded using an ergometer and a force platform that registered the center of foot pressure (COP). We analyzed the COP surface, the mean COP velocity and the spectral power density given by the wavelet transform. Recordings were performed before (PRE condition) and after the completion of each fatiguing task (immediately POST condition, after a 5 min recovery POST 5 condition). In POST condition, the ES exercise affected MVC more than the VOL exercise. However, bipedal postural control was similarly deteriorated for both exercises. In POST 5 condition, for both fatiguing exercises, muscle strength and postural control did not recover their initial level. These results suggest that the postural control disturbance could not be distinguished for the two fatiguing exercises in the bipedal stance. In addition, the recovery speeds of postural control and muscle strength abilities did not differ for the ES exercise and the VOL exercise.


Assuntos
Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Equilíbrio Postural/fisiologia , Músculo Quadríceps/fisiologia , Estimulação Elétrica/métodos , Ergometria , Humanos , Contração Isométrica , Masculino , Força Muscular , Adulto Jovem
14.
Neurosci Res ; 68(4): 301-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20723569

RESUMO

One session of sustained unilateral voluntary muscular contractions increases central fatigue and induces a cross-over of fatigue of homologous contralateral muscles. It is not known, however, how this cross-transfer affects contralateral unipedal postural control. Moreover, contralateral neurophysiological effects differ between voluntary muscular contractions and electrically stimulated contractions. The aims of this study were thus to examine the effects of muscle fatigue on contralateral unipedal postural control and to compare the effects of stimulated and voluntary contractions. Fifteen subjects took part in the protocol. Fatigue of the ipsilateral quadriceps femoris was generated either by neuromuscular electrical stimulation (NMES) or by isometric voluntary muscular contraction (VOL). Postural control on the contralateral limb was measured before (PRE condition) and after the completion of the two fatiguing exercises (POST condition) using a force platform. We analyzed body sway area and the spectral power density given by the wavelet transform. In POST condition, postural control recorded in the unipedal stance on the contralateral limb was disturbed after NMES and VOL fatiguing exercises. In addition, postural control was similarly disturbed for both exercises. These results suggest that cross-over fatigue is able to disturb postural control after both stimulated and voluntary contractions.


Assuntos
Lateralidade Funcional/fisiologia , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Postura/fisiologia , Estimulação Elétrica , Humanos , Masculino , Adulto Jovem
15.
Neurosci Lett ; 477(1): 48-51, 2010 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-20417250

RESUMO

Muscle fatigue affects muscle strength and postural control. However, it is not known whether impaired postural control after fatiguing muscular exercise depends on the nature of the muscle contraction. To answer this question, the present study analyzes changes in postural control after two fatiguing exercises of equal duration and intensity but that induced different magnitudes of strength loss. The effects of fatiguing contractions of the femoris quadriceps were compared for voluntary muscular contraction (VOL) and neuromuscular electrical stimulation (ES) on muscle strength and postural control. Seventeen subjects completed these two fatiguing exercises. Maximal voluntary contraction (MVC) and postural control were recorded using an isokinetic dynamometer and a force platform that recorded the center of foot pressure. Recordings were performed before and after the completion of both fatiguing tasks. Results indicate that, after a fatiguing exercise, the ES exercise affected MVC more than the VOL exercise. Inversely, postural control was disturbed more after VOL exercise than after ES exercise. In conclusion, postural control disturbance is influenced by the nature of the muscular contraction (voluntary vs. non-voluntary) and the type of the motor unit solicited (tonic vs. phasic) rather than by the magnitude of strength loss.


Assuntos
Fadiga/fisiopatologia , Contração Muscular , Postura , Músculo Quadríceps/fisiopatologia , Estimulação Elétrica , Humanos , Masculino , Força Muscular , Músculo Quadríceps/inervação , Adulto Jovem
16.
Rev Prat ; 59(7): 949-51, 954, 2009 Sep 20.
Artigo em Francês | MEDLINE | ID: mdl-19839462

RESUMO

First line standard treatment of metastatic non-small-cell lung cancer is based on intravenous chemotherapy. Chemotherapy has been demonstrated to increase survival, to reduce symptoms and to improve quality of life. Bevacizumab, a monoclonal antibody inhibiting angiogenesis, improves survival when combined with chemotherapy. Because of a risk of hemoptysis, bevacizumab can only be delivered to non-squamous tumours with no proximal vascular invasion. Systemic treatment decision results from a multidisciplinary discussion and takes into account both patient (mostly performance status, age, and comorbidity) and tumour characteristics (histology, tumor location).


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/secundário , Humanos
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