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INTRODUCTION: Several studies have assessed and validated the impact of exoskeletons on back and shoulder muscle activation; however, limited research has explored the role that exoskeletons could play in mitigating lower arm-related disorders. This study assessed the impact of Ironhand, an active hand exoskeleton (H-EXO) designed to reduce grip force exertion, on worker exertion levels using a two-phase experimental design. METHOD: Ten male participants performed a controlled, simulated drilling activity, while three male participants completed an uncontrolled concrete demolition activity. The impact of the exoskeleton was assessed in terms of muscle activity across three different muscles using electromyography (EMG), perceived exertion, and perceived effectiveness. RESULTS: Results indicate that peak muscle activation decreased across the target muscle group when the H-EXO was used, with the greatest reduction (27%) observed in the Extensor Carpi Radialis (ECR). Using the exoskeleton in controlled conditions did not significantly influence perceived exertion levels. Users indicated that the H-EXO was a valuable technology and expressed willingness to use it for future tasks. PRACTICAL APPLICATIONS: This study showcases how glove-based exoskeletons can potentially reduce wrist-related disorders, thereby improving safety and productivity among workers. Future work should assess the impact of the H-EXO in various tasks, different work environments and configurations, and among diverse user groups.

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The influence of extrinsic hand-feel touch cues on consumer experiences in food and beverage consumption is well established. However, their impact on trigeminal perception, particularly the oral irritation caused by capsaicin or spicy foods, is less understood. This study aimed to determine the existence of cross-modal associations between hand-feel touch and capsaicin-induced oral irritation. This study investigated whether these potential associations were driven by the sensory contributions of the hand-feel tactile materials (measured by instrumental physical parameters) or by affective responses (evaluated through hedonic scales and the self-reported emotion questionnaire, EsSense Profile®, by consumers). In our study, 96 participants tasted a capsaicin solution while engaging with nine hand-feel tactile materials, i.e., cardboard, linen, rattan, silicone, stainless steel, sandpaper (fine), sandpaper (rough), sponge, and towel. They subsequently rated their liking and emotional responses, perceived intensity of oral irritation, and the congruency between hand-feel tactile sensation and oral irritation. Instrumental measurements characterized the surface texture of the hand-feel tactile materials, which were correlated with the collected sensory data. The results revealed that unique cross-modal associations between hand-feel touch and capsaicin-induced oral irritation. Specifically, while sandpapers demonstrated high congruence with the sensation of oral irritation, stainless steel was found to be least congruent. These associations were influenced by both the common emotional responses ("active," "aggressive," "daring," "energetic," "guilty," and "worried") evoked by the hand-feel tactile materials and the capsaicin, as well as by participants' liking for the hand-feel tactile materials and the characteristics of the surface textures. This study provides empirical evidence of the cross-modality between hand-feel tactile sensations and capsaicin-induced oral irritation, opening new avenues for future research in this area.

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BACKGROUND AND PURPOSE:  The duration of antibiotic coverage in hand tissues during surgery is unknown. We investigated the time the free concentration of cefuroxime was above the minimal inhibitory concentration (fT>MIC) of 4 µg/mL in hand tissues after single and repeated administration. METHODS:  In a prospective, unblinded randomized study 16 patients (13 female, age range 51-80 years) underwent trapeziectomy. Microdialysis catheters were placed in the metacarpal bone (primary effect parameter), synovial sheath, and subcutaneous tissue. Patients were randomized to postoperative administration of either intravenous single administration of cefuroxime (1,500 mg) (Group 1, n = 8) or repeated dosing (2 x 1,500 mg) with a 4 h interval (Group 2, n = 8). Samples were taken over 8 h. RESULTS: The fT>MIC of 4 µg/mL was found to be significantly longer in the metacarpal bone in Group 2 compared with Group 1 with a mean difference of 199 min (95% confidence interval 158-239). The same trend was evident in the remaining compartments. A concentration of 4 µg/mL was reached in all compartments in both groups within a mean time of 6 min (range 0-27 min). In Group 1, the mean concentrations decreased below 4 µg/mL between 3 h 59 min and 5 h 38 min. CONCLUSION:  The fT>MIC was longer after repeated administration compared with single administration in all compartments. A single administration of cefuroxime 1,500 mg provided antimicrobial hand tissue coverage for a minimum of 3 h 59 min. Cefuroxime administration in hand surgeries should be done minimum 27 min prior to incision to achieve sufficient coverage in all individuals. Cefuroxime readministration should be considered in hand surgeries lasting longer than 4 h from time of administration.

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Stroke is an acute cerebrovascular disease in which sudden interruption of blood supply to the brain or rupture of cerebral blood vessels cause damage to brain cells and consequently impair the patient's motor and cognitive abilities. A novel rehabilitation training model integrating brain-computer interface (BCI) and virtual reality (VR) not only promotes the functional activation of brain networks, but also provides immersive and interesting contextual feedback for patients. In this paper, we designed a hand rehabilitation training system integrating multi-sensory stimulation feedback, BCI and VR, which guides patients' motor imaginations through the tasks of the virtual scene, acquires patients' motor intentions, and then carries out human-computer interactions under the virtual scene. At the same time, haptic feedback is incorporated to further increase the patients' proprioceptive sensations, so as to realize the hand function rehabilitation training based on the multi-sensory stimulation feedback of vision, hearing, and haptic senses. In this study, we compared and analyzed the differences in power spectral density of different frequency bands within the EEG signal data before and after the incorporation of haptic feedback, and found that the motor brain area was significantly activated after the incorporation of haptic feedback, and the power spectral density of the motor brain area was significantly increased in the high gamma frequency band. The results of this study indicate that the rehabilitation training of patients with the VR-BCI hand function enhancement rehabilitation system incorporating multi-sensory stimulation can accelerate the two-way facilitation of sensory and motor conduction pathways, thus accelerating the rehabilitation process.

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BACKGROUND: The reconstruction of complex wounds of the hand still has challenges in achieving aesthetic, functional and sensory recovery. We presented our experience of using the polyfoliate and chimeric radial collateral artery perforator flaps (RCAPF) to repair complex hand defects, aiming to explore the feasibility of special-form RCAPFs in hand coverage and enhance the comprehension of their respective indications. METHODS: From June 2014 to March 2021, 26 cases (19 males and 7 females, mean 44.4 years) underwent defect and sensation reconstruction of their hands with special-form RCAPFs, which manifested as multiple adjacent or irregular single wounds and composite tissue defects complicated with a degree of nerve injury. The clinical effects of the free RCAPFs were evaluated by integrating the postoperative and long-term follow-up outcomes of all cases. RESULTS: Altogether 8 polyfoliate flaps, 17 chimeric flaps and 1 polyfoliate-chimeric flap were harvested. Of them, 23 flaps survived uneventfully in one stage. Venous congestion occurred in 3 cases, two of which survived through vascular exploration and another one was finally repaired by the contralateral RCAPF. The follow-up results showed that the appearance of both the recipient and donor sites mostly recovered satisfactory. All the bone flaps properly healed. The BMRC sensory evaluation results of all skin flaps were S4 in 8 flaps, S3 in 18 flaps, and S2 in 9 flaps. CONCLUSIONS: The free RCAPFs can be designed in various forms with a reliable blood supply, contributing to reconstructing simple and multiple wounds of the hand with or without bone defects and dead space.

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BACKGROUND: Hand function assessment heavily relies on specific task scenarios, making it challenging to ensure validity and reliability. In addition, the wide range of assessment tools, limited and expensive data recording, and analysis systems further aggravate the issue. However, smartphones provide a promising opportunity to address these challenges. Thus, the built-in, high-efficiency sensors in smartphones can be used as effective tools for hand function assessment. OBJECTIVE: This review aims to evaluate existing studies on hand function evaluation using smartphones. METHODS: An information specialist searched 8 databases on June 8, 2023. The search criteria included two major concepts: (1) smartphone or mobile phone or mHealth and (2) hand function or function assessment. Searches were limited to human studies in the English language and excluded conference proceedings and trial register records. Two reviewers independently screened all studies, with a third reviewer involved in resolving discrepancies. The included studies were rated according to the Mixed Methods Appraisal Tool. One reviewer extracted data on publication, demographics, hand function types, sensors used for hand function assessment, and statistical or machine learning (ML) methods. Accuracy was checked by another reviewer. The data were synthesized and tabulated based on each of the research questions. RESULTS: In total, 46 studies were included. Overall, 11 types of hand dysfunction-related problems were identified, such as Parkinson disease, wrist injury, stroke, and hand injury, and 6 types of hand dysfunctions were found, namely an abnormal range of motion, tremors, bradykinesia, the decline of fine motor skills, hypokinesia, and nonspecific dysfunction related to hand arthritis. Among all built-in smartphone sensors, the accelerometer was the most used, followed by the smartphone camera. Most studies used statistical methods for data processing, whereas ML algorithms were applied for disease detection, disease severity evaluation, disease prediction, and feature aggregation. CONCLUSIONS: This systematic review highlights the potential of smartphone-based hand function assessment. The review suggests that a smartphone is a promising tool for hand function evaluation. ML is a conducive method to classify levels of hand dysfunction. Future research could (1) explore a gold standard for smartphone-based hand function assessment and (2) take advantage of smartphones' multiple built-in sensors to assess hand function comprehensively, focus on developing ML methods for processing collected smartphone data, and focus on real-time assessment during rehabilitation training. The limitations of the research are 2-fold. First, the nascent nature of smartphone-based hand function assessment led to limited relevant literature, affecting the evidence's completeness and comprehensiveness. This can hinder supporting viewpoints and drawing conclusions. Second, literature quality varies due to the exploratory nature of the topic, with potential inconsistencies and a lack of high-quality reference studies and meta-analyses.

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Intercepting moving targets is a fundamental skill in human behavior, influencing various domains such as sports, gaming, and other activities. In these contexts, precise visual processing and motor control are crucial for adapting and navigating effectively. Nevertheless, there are still some gaps in our understanding of how these elements interact while intercepting a moving target. This study explored the dynamic interplay among eye movements, pupil size, and interceptive hand movements, with visual and motion uncertainty factors. We developed a simple visuomotor task in which participants used a joystick to interact with a computer-controlled dot that moved along two-dimensional trajectories. This virtual system provided the flexibility to manipulate the target's speed and directional uncertainty during chase trials. We then conducted a geometric analysis based on optimal angles for each behavior, enabling us to distinguish between simple tracking and predictive trajectories that anticipate future positions of the moving target. Our results revealed the adoption of a strong interception strategy as participants approached the target. Notably, the onset and amount of optimal interception strategy depended on task parameters, such as the target's speed and frequency of directional changes. Furthermore, eye-tracking data showed that participants continually adjusted their gaze speed and position, continuously adapting to the target's movements. Finally, in successful trials, pupillary responses predicted the amount of optimal interception strategy while exhibiting an inverse relationship in trials without collisions. These findings reveal key interactions among visuomotor parameters that are crucial for solving complex interception tasks.

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BACKGROUND: Previous studies have reported that the sense of "self" is associated with specific brain regions and neural network activities. In addition, the mirror system, which functions when executing or observing an action, might contribute to differentiating the self from others and form the basis of the sense of self as a fundamental physical representation. This study investigated whether differences in mu suppression, an indicator of mirror system activity, reflect cognitions related to self-other discrimination. METHODS: The participants were 30 of healthy college students. The participants observed short video clips of hand movements performed by themselves or actors from two perspectives (i.e., first-person and third-person). The electroencephalogram (EEG) mu rhythm (8-13 Hz) was measured during video observation as an index of mirror neuron system activity. EEG activity related to self-detection was analyzed using participants' hand movements as self-relevant stimuli. RESULTS: The results showed that mu suppression in the 8-13-Hz range exhibited perspective-dependent responses to self/other stimuli. There was a significant self-oriented mu suppression response in the first-person perspective. However, the study found no significant response orientation in the third-person perspective. The results suggest that mirror system activity may involve self-other discrimination differently depending on the perspective. CONCLUSIONS: In summary, this study examined the mirror system's activity for self and others using the EEG's mu suppression. As a result, it was suggested that differences in self and others or perspectives may influence mu suppression.

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Weight-bearing skin cells show promising therapeutic potential.

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Skin identity is controlled by intrinsic features of the epidermis and dermis and their interactions. Modifying skin identity has clinical potential, such as the conversion of residual limb and stump (nonvolar) skin of amputees to pressure-responsive palmoplantar (volar) skin to enhance prosthesis use and minimize skin breakdown. Greater keratin 9 (KRT9) expression, higher epidermal thickness, keratinocyte cytoplasmic size, collagen length, and elastin are markers of volar skin and likely contribute to volar skin resiliency. Given fibroblasts' capacity to modify keratinocyte differentiation, we hypothesized that volar fibroblasts influence these features. Bioprinted skin constructs confirmed the capacity of volar fibroblasts to induce volar keratinocyte features. A clinical trial of healthy volunteers demonstrated that injecting volar fibroblasts into nonvolar skin increased volar features that lasted up to 5 months, highlighting a potential cellular therapy.

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This single-participant case study examines the feasibility of using custom virtual reality (VR) gaming software in the home environment for low-dose Hand Arm Bimanual Intensive Training (HABIT). A 10-year-old with right unilateral cerebral palsy participated in this trial. Fine and gross motor skills as well as personal goals for motor outcomes were assessed before and after the intervention using the Box and Blocks Test, Nine-Hole Peg Test, and Canadian Occupational Performance Measure. Movement intensities collected via the VR hardware accelerometers, VR game scores, and task accuracy were recorded via the HABIT-VR software as indices of motor performance. The child and family were instructed to use the HABIT-VR games twice daily for 30 minutes over a 14-day period and asked to record when they used the system. The child used the system and completed the 14-hour, low-dose HABIT-VR intervention across 22 days. There was no change in Box and Blocks Test and Nine-Hole Peg Test scores before and after the intervention. Canadian Occupational Performance Measure scores increased but did not reach the clinically relevant threshold, due to high scores at baseline. Changes in motor task intensities during the use of VR and mastery of the VR bimanual tasks suggested improved motor efficiency. This case study provides preliminary evidence that HABIT-VR is useful for promoting adherence to HABIT activities and for the maintenance of upper extremity motor skills in the home setting.

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This study addresses the need for highly sensitive tools to evaluate hand strength, particularly grasp and pinch strength, which are vital for diagnosing and rehabilitating conditions affecting hand function. Current devices like the Jamar dynamometer and Martin Vigorimeter, although reliable, fail to measure extremely low force or pressure values required for individuals with severe hand impairments. This research introduces a novel device, a modified Martin Vigorimeter, utilizing an ultra-soft latex chamber and differential pressure measurement to detect minute pressure changes, thus significantly enhancing sensitivity. The device offers a cost-effective solution, making advanced hand strength evaluation more accessible for clinical and research applications. Future research should validate its accuracy across diverse populations and settings, exploring its broader implications for hand rehabilitation and occupational health.

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During the investigation of firearm-related incidents, gunshot residues (GSR) can be collected on the scene and individuals (e.g., shooters or bystanders). Their analysis can give valuable information for the reconstruction of the events. Since GSR collection on persons of interest generally occurs a few minutes to hours after discharge, knowledge is needed to understand how organic (O), and inorganic (I) residues are transferred and persist. In this research, the quantities of OGSR and IGSR were assessed on the right and left hands, forearms, face, and nostrils of four shooters. Specimens were collected immediately before the discharge (shooter's blank specimens) and shortly after (30 min) using carbon adhesive stubs. Organic compounds were first extracted from the collection device and analysed using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Subsequently, IGSR particles were detected on the same stub using scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDS). Shooter's blank specimen analysis revealed background contamination of both O and IGSR in the shooter's environment, predominantly attributed to the presence of an indoor shooting range. However, the background quantities generally remained below the associated 30-minute specimen. Thirty minutes after a discharge, higher quantities were generally detected on the shooter's right and left hands than on other collection regions for both GSR types. Forearms and face emerged as interesting collection alternatives, especially in cases where a person of interest may have washed their hands in the interval between the discharge and collection. In contrast, very low amounts of GSR were detected in the nostrils. Furthermore, the results indicated that OGSR and IGSR have different transfer and persistence mechanisms.

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INTRODUCTION: Aortic arch complex atheromatosis is a source of cerebral embolism. A percentage of lacunar infarct could be of embolic etiology, especially due to microemboli of the aortic arch. CASE REPORT: We present the case of a 63-year-old hypertensive man suffering from dysarthria-clumsy hand syndrome for a right hemispheric minor ischemic stroke. The patient developed sequential acute thromboembolism of the left lower and right upper limbs. Computed tomography angiography revealed an aortic arch thrombus. Vascular surgery was successfully performed. CONCLUSION: This case highlights the importance of considering embolic sources in lacunar syndromes, especially at the level of the aortic arch.

TITLE: Síndrome de disartria-mano torpe y embolias agudas secuenciales múltiples de las extremidades como forma de presentación de un trombo del cayado aórtico.Introducción. La ateromatosis del complejo del arco aórtico es una fuente de embolia cerebral. Un porcentaje de infartos lacunares podría ser de etiología embólica, especialmente debidos a microembolias del arco aórtico. Caso clínico. Presentamos el caso de un varón hipertenso de 63 años con síndrome de disartria-mano torpe por un ictus isquémico minor hemisférico derecho. El paciente desarrolló un tromboembolismo agudo secuencial de los miembros inferior izquierdo y superior derecho. La angiografía por tomografía computarizada reveló un trombo en el arco aórtico. La cirugía vascular se llevó a cabo con éxito. Conclusión. Este caso destaca la importancia de considerar las fuentes embólicas en los síndromes lacunares, especialmente en el arco aórtico.

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Class demonstrations where the lecturer's hand motor actions are observable generally have a positive effect on the learning of motor skills because they trigger an effortless process of embodied simulations. Whether the learning of cognitive skills is likewise affected by such visualisations is yet to be investigated and might depend on the learning content as well as other factors. This study aimed to investigate whether showing the lecturer's hand via a document camera during an introductory financial accounting class affects student learning (transfer performance), cognitive load responses, and note-taking behaviour compared to a writing pad where the lecturer's hand is not visible. The study utilised a quasi-experimental design in an in-person setting, with a pre-test and post-test comparison of two groups of participants: one group that viewed a lecture video without the lecturer's hand being visible (n = 509), and another group that viewed the same lecture with the lecturer's hand being visible (n = 571). The results showed that the with-hand group had a significantly higher increase in test scores compared to the without-hand group. However, the visibility of the hand did not significantly impact cognitive load or note-taking behaviour. The findings have important practical implications for education, as incorporating non-verbal cues such as the lecturer's hand may effectively enhance learning cognitive skills.

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BACKGROUND: Even though tuberculosis is a common disease among children in developing countries, tuberculous dactylitis is an uncommon form of Skeletal tuberculosis specially with involvement of both the hands and feet. CASE PRESENTATION: A one-and-a-half-year-old previously healthy female Ethiopian toddler presented to our pediatric outpatient clinic with a history of two-month duration of painful multiple swellings over both her hands and feet. The swelling involved the proximal phalanx of the left index finger, dorsum of the right hand, and dorsum of both feet over the first metatarsal bone. Physical examination, radiologic findings, and histopathology suggested tuberculous dactylitis. The patient was treated with anti-tuberculosis drugs for one year and she showed clinical and radiologic improvement and recovery. CONCLUSION: Tubercular dactylitis should be considered in the differential diagnosis of children from endemic areas presenting with bone and joint pain or swelling. Our experience of a twelve-month course of antitubercular treatment, which is in line with WHO recommendations, for skeletal tuberculosis, showed excellent outcomes.

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The loss of a hand disrupts the sophisticated neural pathways between the brain and the hand, severely affecting the level of independence of the patient and the ability to carry out daily work and social activities. Recent years have witnessed a rapid evolution of surgical techniques and technologies aimed at restoring dexterous motor functions akin to those of the human hand through bionic solutions, mainly relying on probing of electrical signals from the residual nerves and muscles. Here, we report the clinical implementation of an interface aimed at achieving this goal by exploiting muscle deformation, sensed through passive magnetic implants: the myokinetic interface. One participant with a transradial amputation received an implantation of six permanent magnets in three muscles of the residual limb. A truly self-contained myokinetic prosthetic arm embedding all hardware components and the battery within the prosthetic socket was developed. By retrieving muscle deformation caused by voluntary contraction through magnet localization, we were able to control in real time a dexterous robotic hand following both a direct control strategy and a pattern recognition approach. In just 6 weeks, the participant successfully completed a series of functional tests, achieving scores similar to those achieved when using myoelectric controllers, a standard-of-care solution, with comparable physical and mental workloads. This experience raised conceptual and technical limits of the interface, which nevertheless pave the way for further investigations in a partially unexplored field. This study also demonstrates a viable possibility for intuitively interfacing humans with robotic technologies.

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