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Objectives: T2*‐weighted magnetic resonance imaging (MRI) sequences have been identified as non‐invasive tools with which to study placental oxygenation in vivo. This study aimed to use these to investigate both static and dynamic responses to hyperoxia of the normal placenta across gestation. Methods: We conducted a single‐center prospective study including 52 uncomplicated pregnancies. Two T2*‐weighted sequences (T2* relaxometry) were performed, one before and one after maternal hyperoxia. The distribution of placental T2* values was modeled by fitting a gamma probability density function (T2* ~Γαβ), describing the structure of the histogram using the mean T2* value, the shape parameter (α) and the rate (β). A dynamic acquisition (blood‐oxygen‐level‐dependent (BOLD) MRI) was also performed before and during maternal oxygen supply, until placental oxygen saturation had been achieved. The signal change over time was modeled using a sigmoid function, to determine the intensity of enhancement (ΔBOLD (% with respect to baseline)), a temporal variation coefficient (λ (min–1), controlling the slope of the curve) and the maximum steepness (Vmax (% of placental enhancement/min)). Results: The histogram analysis of the T2* values in normoxia showed a whole‐placenta variation, with a decreasing linear trend in the mean T2* value (Pearson's correlation coefficient (R) = −0.83 (95% CI, −0.9 to −0.71), P < 0.001), along with an increasingly peaked and narrower distribution of T2* values with advancing gestation. After maternal hyperoxia, the mean T2* ratios (mean T2*hyperoxia/mean T2*baseline) were positively correlated with gestational age, while the other histogram parameters remained stable, suggesting a translation of the histogram towards higher values with a similar appearance after maternal hyperoxia. ΔBOLD showed a non‐linear increase across gestation. Conversely, λ showed an inverted trend across gestation, with a weaker correlation (R = −0.33 (95% CI, −0.58 to −0.02), P = 0.04, R2 = 0.1). As a combination of ΔBOLD and λ, the changes in Vmax throughout gestation were influenced mainly by the changes in ΔBOLD and showed a positive non‐linear correlation with gestational age. Conclusions: Our results suggest that the decrease in the T2* placental signal as gestation progresses does not reflect placental dysfunction. The BOLD dynamic signal change is representative of a free‐diffusion model of oxygenation and highlights the increasing differences in oxygen saturation between mother and fetus as gestation progresses (ΔBOLD) and in the placental permeability to oxygen (λ). © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Employers can work to prevent falling accidents in the workplace if they understand all the intrinsic and extrinsic factors that can lead to falls. Intrinsic factors, which focus on the individual , include postural control problems, inner ear infections and vertigo. Extrinsic, or environmental problems include shoes, lighting, and floor conditions.

This article discusses the potential of "black bone" (BB) MRI imaging sequences as an alternative to conventional radiography for examining the skeleton in fetuses during post-mortem MRI examinations. The study involved 60 fetuses, and skeletal abnormalities were found in 31.6% of cases. The overall sensitivity and specificity of BB MRI for skeletal pathology were 89.4% and 97.5% respectively. The main limitation of fetal BB MRI sequences was the diagnosis of craniosynostosis. The authors conclude that BB MRI imaging sequences offer a radiation-free method for imaging the fetal skeleton and could be a potential alternative to radiography for analyzing bone anomalies. [Extracted from the article]

Diffusion tensor Imaging (DTI) and tractography offer a unique possibility to visualise and evaluate the developing white matter in fetal brain. DTI could be used to explore the normal spinal cord development and to study pathological development of the spinal cord. The aim of this preliminary study was to assess the feasibility of DTI and tractography in the evaluation of the fetal spinal cord. [Extracted from the article]

Background: Ageing is associated with a reduction in balance, in particular through dysfunction of each level of postural control, which results in an increased risk of falling. Conversely, the practice of physical activities has been shown to modulate postural control in elderly people.Objective: This study examined the potential positive effects of two types of regular physical and sporting activities on vestibular information and their relation to posture.Methods: Gaze and postural stabilisation was evaluated by caloric and rotational vestibular tests on 18 healthy subjects over the age of 60 who regularly practised low-energy or bioenergetic physical activities and on 18 controls of a similar age who only walked on a regular basis. These subjects were also submitted to static and dynamic posturographic tests.Results: The control group displayed less balance control, with a lower vestibular sensitivity and a relatively high dependency on vision compared to the group practising low-energy physical activities, which had better postural control with good vestibular sensitivity and less dependency on vision. The postural control and vestibular sensitivity of subjects practising bioenergetic activities was average, and required higher visual afferent contribution.Conclusion: Low-energy exercises, already shown to have the most positive impact on balance control by relying more on proprioception, also appear to develop or maintain a high level of vestibular sensitivity allowing elderly people practising such exercises to reduce the weight of vision. [ABSTRACT FROM AUTHOR]

Objectives. Musculoskeletal disorders (MSDs) represent a prevalent global occupational health concern, primarily associated with high biomechanical solicitations, mental workload and work pace. Although cobots have shown promise in reducing risks of MSDs, a question of interest still persists as to how the pace in hybrid human–machine collaboration will affect the operator, in terms of both physical and cognitive health and the production.Methods. This study aimed to analyse the impact of pace on productivity, operators’ posture and mental workload in a human–cobot collaboration. The study, involving 20 participants engaged in a collaborative task with a cobot under three cobot-led paces, assessed productivity rapid upper limb assessment (RULA) scores (posture), dual task performance (cognitive resources) and NASA task load index (NASA-TLX) scores (workload).Results. The findings revealed that an excessively high pace had counterproductive effects, leading to reduced efficiency and increased susceptibility to MSDs, both in terms of physical and mental workloads.Conclusion. In the context of a human–cobot collaboration, it is imperative to adapt the pace to operators’ abilities in order to ensure optimal productivity while preserving their health, emphasizing the need for a balanced approach to pace management in such collaborative work scenarios. [ABSTRACT FROM AUTHOR]

Objective: School-behavior-health difficulties (SBHDs) may alter physical/mental capabilities and consequently increase injury risk during daily activities. This study assessed the associations of potential SBHDs and their cumulative number (SBHDcn) with various injury types among younger adolescents. Methods: The study population included 1,559 middle-school adolescents in France (10-18 years, 98% under 16,778 boys and 781 girls). They completed a questionnaire at school-year end collecting socioeconomic features (nationality, family structure, parents' education/occupation/income), school/out-of-school injuries during the school-year (dependent variables), and SBHDs starting before the school-year (low academic performance, alcohol/tobacco/cannabis/other-illicit-drugs use, physical/verbal violence, sexual abuse, perpetrated violence, poor social support, poor general health status, sleep difficulty, depressive symptoms, and suicide attempt). Data were analyzed using logistic regression models and Kaplan-Meier estimates. Results: Injuries were frequent during school-physical/sports-training (10.9%), other-school-training (4.7%), school-free-time (7.4%), out-of-school-sports-activity (16.5%), and traffic (2.2%). Single injury (one injury all injury types combined) and ≥2 injury types affected 23.3 and 7.9% of subjects, respectively. The proportion of adolescents without SBHDs decreased with age more quickly among those with each injury type than among those without injury. Various SBHDs were associated with most injury types, single injury, and ≥2 injury types (sex-age-adjusted odds/relative-risk ratios reaching 11, p < .001). A dose-effect association was found between SBHDcn 1-2/3-5/≥6 and both single injury and ≥2 injury types (sex-age adjusted relative risk ratios reaching 12.66, p < .001, vs. SBHDcn = 0). Socioeconomic features had a moderate confounding role in these associations. Conclusions: SBHDs strongly predict injuries among adolescents. Our findings may inform healthcare providers about their prominent role in detecting/reducing SBHDs and injuries.

Objective: Lack of regular physical activity (LPA) and the number of days/week with physical activity >60 minutes/day (Ndw) may be associated with school-health-relational difficulties (SHRDs) during the life-course. This study assessed their associations and the confounding role of socioeconomic features (nationality, family structure, parents' education/occupation/income) among younger adolescents. Methods: This cross-sectional population-based study included 1,559 middle-school adolescents from north-eastern France (10-18 years, 98% under 16 years, 778 boys and 781 girls). They completed over one-hour teaching period a questionnaire collecting last-12-month LPA and last-7-day Ndw (dependent variables), and risk factors including socioeconomic features, SHRDs (previous grade repetitions, last-12-month poor general health status/physical health/psychological health/social-relationships, depressive symptoms (and age at onset and duration from onset); cumulated number noted SHRDcn). Data were analyzed using logistic/linear regression models. Results: LPA was common (32.5%) and associated with all SHRDs (sex-age-adjusted odds ratio saOR reaching 1.99, p  < .001) and depressive-symptoms duration (saOR 1.63 ( p  < .05) and 2.11 ( p  < .001) for 1-2 and ≥3 years, respectively, vs. no depressive symptoms). A dose-effect association was found between SHRDcn and LPA (24.0, 33.7, 45.6, and 53.5%; saOR 1.59, 2.58, and 3.43; for SHRDcn 1-2, 3-4, and ≥5 respectively, vs. SHRDcn = 0, p  < .001). Ndw was similarly associated with all SHRDs and SHRDcn (sex-age-adjusted regression coefficient reaching -1.10 day/week, p  < .001). These results were robust when controlling for socioeconomic features (18%

Musculoskeletal disorders (MSDs) are the main occupational diseases and are pathologies of multifactorial origin, with posture being one of them. This creates new human-robot collaboration situations that can modify operator behaviors and performance in their task. These changes raise questions about human-robot team performance and operator health. This study aims to understand the consequences of introducing a cobot on work performance, operator posture, and the quality of interactions. It also aims to evaluate the impact of two levels of difficulty in a dual task on these measures. For this purpose, thirty-four participants performed an assembly task in collaboration with a co-worker, either a human or a cobot with two articulated arms. In addition to this motor task, the participants had to perform an auditory task with two levels of difficulty (dual task). They were equipped with seventeen motion capture sensors. The collaborative work was filmed with a camera, and the actions of the participants and co-worker were coded based on the dichotomy of idle and activity. Interactions were coded based on time out, cooperation, and collaboration. The results showed that performance (number of products manufactured) was lower when the participant collaborated with a cobot rather than a human, with also less collaboration and activity time. However, RULA scores were lower-indicating a reduced risk of musculoskeletal disorders-during collaboration with a cobot compared to a human. Despite a decrease in production and a loss of fluidity, likely due to the characteristics of the cobot, working in collaboration with a cobot makes the task safer in terms of the risk of musculoskeletal disorders., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Bouillet et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In recent years, immersive virtual reality technology has emerged in the field of health. Its use could allow the assessment of the motor behavior of individuals in adaptable and reproducible immersive environments, simulating real situations. This study aimed to assess the effect of an immersive scenario on functional mobility during a simple locomotor task according to age. Sixty young adults and 60 older volunteers, who were autonomous and without cognitive and neurological impairment participated. A locomotor task based on the "Timed Up and Go" task was performed in real and virtual conditions. A functional mobility score was calculated by combining the time and the number of steps used and compared between young and older people. Results showed that correlations between time and the number of steps were the same in VR and real conditions, but the locomotor performance decreased significantly in VR for both populations. Additionally, older people exhibited a more reduced locomotor performance in a virtual environment than young adults, thereby their functional mobility score decreased more to complete the task, reflecting the adoption of a more secure locomotion strategy often related to the fear of falling, with an increase in time and number of steps to support balance. The major difference between reality and VR is the visual immersion with an HMD, and visual information is more important in the sensory integration of older people. Therefore, the reduction in visual field and lack of visual exproprioceptive information about the body segments in the virtual environment could explain these results. Finally, the effect of immersion in a virtual scenario on mobility exists for both populations but is accentuated by the aging process and is therefore age dependent., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Renaux, Clanché, Muhla, Duclos, Meyer, Colnat-Coulbois and Gauchard.)