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1.
PLoS One ; 19(4): e0298958, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38564497

RESUMEN

Mental fatigue is common in society, but its effects on force production capacities remain unclear. This study aimed to investigate the impact of mental fatigue on maximal force production, rate of force development-scaling factor (RFD-SF), and force steadiness during handgrip contractions. Fourteen participants performed two randomized sessions, during which they either carried out a cognitively demanding task (i.e., a visual attention task) or a cognitively nondemanding task (i.e., documentary watching for 62 min). The mental fatigue was evaluated subjectively and objectively (performances and electroencephalography). Maximal voluntary contraction (MVC) force, RFD-SF, and force steadiness (i.e., force coefficient of variation at submaximal intensities; 25, 50, and 75% of MVC) were recorded before and after both tasks. The feeling of mental fatigue was much higher after completing the cognitively demanding task than after documentary watching (p < .001). During the cognitively demanding task, mental fatigue was evidenced by increased errors, missed trials, and decreased N100 amplitude over time. While no effect was reported on force steadiness, both tasks induced a decrease in MVC (p = .040), a force RFD-SF lower slope (p = .011), and a reduction in the coefficient of determination (p = .011). Nevertheless, these effects were not explicitly linked to mental fatigue since they appeared both after the mentally fatiguing task and after watching the documentary. The study highlights the importance of considering cognitive engagement and mental load when optimizing motor performance to mitigate adverse effects and improve force production capacities.


Asunto(s)
Fuerza de la Mano , Fatiga Muscular , Humanos , Electromiografía , Mano , Factores de Tiempo , Músculo Esquelético , Contracción Isométrica , Contracción Muscular , Fatiga Mental
2.
Sci Rep ; 14(1): 7696, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565576

RESUMEN

The modified total Sharp score (mTSS) is often used as an evaluation index for joint destruction caused by rheumatoid arthritis. In this study, special findings (ankylosis, subluxation, and dislocation) are detected to estimate the efficacy of mTSS by using deep neural networks (DNNs). The proposed method detects and classifies finger joint regions using an ensemble mechanism. This integrates multiple DNN detection models, specifically single shot multibox detectors, using different training data for each special finding. For the learning phase, we prepared a total of 260 hand X-ray images, in which proximal interphalangeal (PIP) and metacarpophalangeal (MP) joints were annotated with mTSS by skilled rheumatologists and radiologists. We evaluated our model using five-fold cross-validation. The proposed model produced a higher detection accuracy, recall, precision, specificity, F-value, and intersection over union than individual detection models for both ankylosis and subluxation detection, with a detection rate above 99.8% for the MP and PIP joint regions. Our future research will aim at the development of an automatic diagnosis system that uses the proposed mTSS model to estimate the erosion and joint space narrowing score.


Asunto(s)
Anquilosis , Luxaciones Articulares , Humanos , Radiografía , Mano/diagnóstico por imagen , Articulaciones de los Dedos , Redes Neurales de la Computación , Anquilosis/diagnóstico por imagen , Luxaciones Articulares/diagnóstico por imagen
3.
MMW Fortschr Med ; 166(6): 30, 2024 04.
Artículo en Alemán | MEDLINE | ID: mdl-38581508

Asunto(s)
Mano , Humanos
4.
Ann Plast Surg ; 92(4S Suppl 2): S132-S135, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38556661

RESUMEN

INTRODUCTION: Vascular malformations (VMs) typically appear at birth and grow commensurately with patients. They can vary broadly in vessel type and tissue involvement, and upper extremity (UE) VMs can pose unique functional and aesthetic challenges in children. Given the advent of operative and nonoperative technologies like sclerotherapy and medications, a contemporary review of the surgical management of UE VMs is warranted. METHODS: We performed a retrospective review of all patients who had surgical management of VMs from 2010 to 2021 at The Children's Hospital of Philadelphia. Demographics, lesion characteristics, treatment (including preceding nonsurgical therapies), complications, and final outcomes were recorded. Operative notes were reviewed for date of operation, depth of excision, type of closure, and current procedural terminology code. RESULTS: Sixty-seven patients with 88 procedures were studied. Average patient age was 5.8 years, with 64% White and 67% male. Venous (34%) and lymphatic (19%) malformations were most common, and anatomic locations were most frequently on the hand (33%) and forearm (25%). The average lesion diameter was 4.2 cm, although this varied by location (eg, 2.9 cm, hand; 11.1 cm, chest wall). Fifty-eight patients (87%) underwent surgical excision as their index procedure, and 9 had sclerotherapy before surgery. Thirty-nine patients (60%) had subcutaneous excisions, and the remainder required subfascial or intramuscular excisions. Nearly all excisions were closed primarily (97%). Of the 53 patients with documented follow-up, 32 patients (60%) had complete resolution of their lesion as of their final visit. Thirty of these 32 patients with no clinical evidence of residual VM had only 1 surgery for excision. CONCLUSION: Upper extremity VMs were composed of diverse conditions with varying vessel types, size, depth, and anatomic sites. Surgical excision of VMs of the UE was safe and effective. A majority of VMs were fully excised after 1 procedure and frequently closed primarily with relatively low complication rates. Future work should investigate decision-making and outcomes of all treatment options of VMs of the UE for optimal functionality and aesthetics.


Asunto(s)
Malformaciones Vasculares , Venas , Niño , Recién Nacido , Humanos , Masculino , Preescolar , Femenino , Estudios Retrospectivos , Venas/cirugía , Malformaciones Vasculares/cirugía , Escleroterapia/métodos , Mano , Resultado del Tratamiento
5.
PLoS One ; 19(4): e0300262, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38557680

RESUMEN

Top managers' past experiences (e.g., foreign experience) significantly impact their decision-making behavior, which may influence firms' sustainable development. The available literature, focusing on the role of the increase in the number of top executives with foreign experience in corporate social responsibility (CSR), yields mixed results. In order to clarify the ambiguous relationship between executive foreign experience and CSR, we empirically examine the effect of the geographic diversity of top executives' foreign experience on CSR. Based on a hand-collected dataset of the top management team's (TMT's) foreign experience, we demonstrate the positive impact of the geographic diversity of returnee executives' foreign experience on firms' CSR using Chinese A-share listed firms from 2009 to 2018. Moreover, this impact is stronger in firms with political connections with the central government and in regions with good market development. Furthermore, the mechanism analysis shows that returnee executives drive firms' CSR by promoting corporate donations and green innovation. This paper offers clear policy implications by suggesting that hiring returnees with a broad geographic scope of foreign experience as corporate executives is an efficient way to enhance firms' CSR.


Asunto(s)
Pueblo Asiatico , Mano , Humanos , Gobierno Federal , Internacionalidad , Selección de Personal , Responsabilidad Social
6.
Sci Rep ; 14(1): 8341, 2024 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594312

RESUMEN

The motor neuroscience literature suggests that the central nervous system may encode some motor commands in terms of velocity. In this work, we tackle the question: what consequences would velocity commands produce at the behavioral level? Considering the ubiquitous presence of noise in the neuromusculoskeletal system, we predict that velocity commands affected by stationary noise would produce "random walks", also known as Brownian processes, in position. Brownian motions are distinctively characterized by a linearly growing variance and a power spectral density that declines in inverse proportion to frequency. This work first shows that these Brownian processes are indeed observed in unbounded motion tasks e.g., rotating a crank. We further predict that such growing variance would still be present, but bounded, in tasks requiring a constant posture e.g., maintaining a static hand position or quietly standing. This hypothesis was also confirmed by experimental observations. A series of descriptive models are investigated to justify the observed behavior. Interestingly, one of the models capable of accounting for all the experimental results must feature forward-path velocity commands corrupted by stationary noise. The results of this work provide behavioral support for the hypothesis that humans plan the motion components of their actions in terms of velocity.


Asunto(s)
Mano , Postura , Humanos , Movimiento (Física)
9.
J Vis ; 24(3): 9, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38546586

RESUMEN

The ability to accurately perceive and track moving objects is crucial for many everyday activities. In this study, we use a "double-drift stimulus" to explore the processing of visual motion signals that underlie perception, pursuit, and saccade responses to a moving object. Participants were presented with peripheral moving apertures filled with noise that either drifted orthogonally to the aperture's direction or had no net motion. Participants were asked to saccade to and track these targets with their gaze as soon as they appeared and then to report their direction. In the trials with internal motion, the target disappeared at saccade onset so that the first 100 ms of the postsaccadic pursuit response was driven uniquely by peripheral information gathered before saccade onset. This provided independent measures of perceptual, pursuit, and saccadic responses to the double-drift stimulus on a trial-by-trial basis. Our analysis revealed systematic differences between saccadic responses, on one hand, and perceptual and pursuit responses, on the other. These differences are unlikely to be caused by differences in the processing of motion signals because both saccades and pursuits seem to rely on shared target position and velocity information. We conclude that our results are instead due to a difference in how the processing mechanisms underlying perception, pursuit, and saccades combine motor signals with target position. These findings advance our understanding of the mechanisms underlying dissociation in visual processing between perception and eye movements.


Asunto(s)
Seguimiento Ocular Uniforme , Movimientos Sacádicos , Humanos , Movimientos Oculares , Mano , Percepción Visual
10.
Int Wound J ; 21(3): e14754, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38436604

RESUMEN

We investigated the contamination of the operator and the surrounding environment during wound debridement through simulated operations using fluorescent labelling. On-site simulated operation assessment was performed before and after the training. Oranges and square towels were used to simulate wounds and the inpatient units, respectively. Fluorescent powder was applied to the surfaces. Operations on oranges simulated bedside debridement, and the postoperative distribution of the fluorescent powder was employed to reflect the contamination of the operator and the surrounding environment. During the pre-training assessment, contamination was observed in 28 of the 29 trainees. The commonly contaminated parts were the extensor side of the forearm, middle abdomen, upper abdomen, and hands. The right side of the operating area was contaminated in 24 trainees. During the post-training assessment, contamination was observed in 13 of the 15 trainees. The commonly parts were the hands, extensor side of the forearm, and the lower abdomen. The front, back, left, and right sides of the operating area were contaminated in 12, 9, 11, and 14 trainees, respectively. Contamination of the treatment cart was observed in 5 trainees. Operator and the surrounding environment can be contaminated during wound debridement. Attention should be paid to hand hygiene, wearing and changing of work clothes, and disinfection of the surrounding environment. Moreover, regular training is recommended.


Asunto(s)
Mano , Extremidad Superior , Humanos , Desbridamiento , Polvos , Antebrazo , Colorantes
11.
J Clin Neuromuscul Dis ; 25(3): 115-121, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38441927

RESUMEN

OBJECTIVE: Ultrasound studies in inclusion body myositis (IBM) have reported a characteristic pattern of increased echointensity in the flexor digitorum profundus (FDP) with relative sparing of the flexor carpi ulnaris (FCU). We examined the relationship between echointensity of the FDP and FCU muscles and hand strength or patient-reported outcomes (PROs). METHODS: A total of 15 patients with IBM were recruited. Ultrasound images of the FDP and FCU muscles were obtained by a point-of-care ultrasound and graded using the modified Heckmatt score. Hand grip and neutral pinch strength were measured by dynamometry. PROs were assessed by the IBM Upper Extremity Function Scale. RESULTS: FDP and/or FCU modified Heckmatt score showed a significant relationship with grip, neutral pinch strength, and PROs. CONCLUSIONS: Point-of-care ultrasound examination of the forearm may serve as an extension of the neuromuscular examination. The semi-qualitative echointensity rating based on modified Heckmatt score seems to correlate well with the objective strength measurement and PROs.


Asunto(s)
Miositis por Cuerpos de Inclusión , Humanos , Miositis por Cuerpos de Inclusión/diagnóstico por imagen , Fuerza de la Mano , Extremidad Superior , Mano/diagnóstico por imagen , Ultrasonografía
12.
Sci Rep ; 14(1): 7620, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38556580

RESUMEN

Radiofrequency ablation (RFA) comparative efficacy of treatments using video-assisted thoracoscopic sympathectomy (VATS) in the long term remains uncertain in patients with palmar hyperhidrosis (PHH). This study aimed to compare the efficacy and safety of RFA and VATS in patients with PHH. We recruited patients aged ≥ 14 years with diagnosed PHH from 14 centres in China. The treatment options of RFA or VATS were assigned to two cohort in patients with PHH. The primary outcome was the efficacy at 1-year. A total of 807 patients were enrolled. After propensity score matching, the rate of complete remission was lower in RFA group than VATS group (95% CI 0.21-0.57; p < 0.001). However, the rates of palmar dryness (95% CI 0.38-0.92; p = 0.020), postoperative pain (95% CI 0.13-0.33; p < 0.001), and surgery-related complications (95% CI 0.19-0.85; p = 0.020) were lower in RFA group than in VATS group, but skin temperature rise was more common in RFA group (95% CI 1.84-3.58; p < 0.001). RFA had a lower success rate than VATS for the complete remission of PHH. However, the symptom burden and cost are lower in patients undergoing RFA compared to those undergoing VATS.Trial Registration: ChiCTR2000039576, URL: http://www.chictr.org.cn/index.aspx .


Asunto(s)
Hiperhidrosis , Ablación por Radiofrecuencia , Humanos , Resultado del Tratamiento , Cirugía Torácica Asistida por Video/efectos adversos , Hiperhidrosis/cirugía , Ablación por Radiofrecuencia/efectos adversos , Simpatectomía/efectos adversos , Mano
15.
J Neuroeng Rehabil ; 21(1): 36, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491540

RESUMEN

BACKGROUND: Recent technological advancements present promising opportunities to enhance the frequency and objectivity of functional assessments, aligning with recent stroke rehabilitation guidelines. Within this framework, we designed and adapted different manual dexterity tests in extended reality (XR), using immersive virtual reality (VR) with controllers (BBT-VR-C), immersive VR with hand-tracking (BBT-VR-HT), and mixed-reality (MD-MR). OBJECTIVE: This study primarily aimed to assess and compare the validity of the BBT-VR-C, BBT-VR-HT and MD-MR to assess post-stroke manual dexterity. Secondary objectives were to evaluate reliability, usability and to define arm kinematics measures. METHODS: A sample of 21 healthy control participants (HCP) and 21 stroke individuals with hemiparesis (IHP) completed three trials of the traditional BBT, the BBT-VR-C, BBT-VR-HT and MD-MR. Content validity of the different tests were evaluated by asking five healthcare professionals to rate the difficulty of performing each test in comparison to the traditional BBT. Convergent validity was evaluated through correlations between the scores of the traditional BBT and the XR tests. Test-retest reliability was assessed through correlations between the second and third trial and usability was assessed using the System Usability Scale (SUS). Lastly, upper limb movement smoothness (SPARC) was compared between IHP and HCP for both BBT-VR test versions. RESULTS: For content validity, healthcare professionals rated the BBT-VR-HT (0[0-1]) and BBT-MR (0[0-1]) as equally difficult to the traditional BBT, whereas they rated BBT-VR-C as more difficult than the traditional BBT (1[0-2]). For IHP convergent validity, the Pearson tests demonstrated larger correlations between the scores of BBT and BBT-VR-HT (r = 0.94;p < 0.001), and BBT and MD-MR (r = 0.95;p < 0.001) than BBT and BBT-VR-C (r = 0.65;p = 0.001). BBT-VR-HT and MD-MR usability were both rated as excellent, with median SUS scores of 83[57.5-91.3] and 83[53.8-92.5] respectively. Excellent reliability was found for the BBT-VR-C (ICC = 0.96;p < 0.001), BBT-VR-HT (ICC = 0.96;p < 0.001) and BBT-MR (ICC = 0.99;p < 0.001). The usability of the BBT-VR-C was rated as good with a median SUS of 70[43.8-83.8]. Upper limb movements of HCP were significantly smoother than for IHP when completing either the BBT-VR-C (t = 2.05;p = 0.043) and the BBT-VR-HT (t = 5.21;p < 0.001). CONCLUSION: The different XR manual tests are valid, short-term reliable and usable tools to assess post-stroke manual dexterity. TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT04694833 ; Unique identifier: NCT04694833, Date of registration: 11/24/2020.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Realidad Virtual , Humanos , Mano , Reproducibilidad de los Resultados , Accidente Cerebrovascular/complicaciones , Extremidad Superior
16.
J Neuroeng Rehabil ; 21(1): 37, 2024 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504351

RESUMEN

BACKGROUND: Children with unilateral cerebral palsy (UCP) are encouraged to participate in the regular school curriculum. However, even when using the less-affected hand for handwriting, children with UCP still experience handwriting difficulties. Visual-motor integration (VMI) is a predictor of handwriting quality. Investigating VMI in children with UCP is important but still lacking. Conventional paper-based VMI assessments is subjective and use all-or-nothing scoring procedures, which may compromise the fidelity of VMI assessments. Moreover, identifying important shapes that are predictive of VMI performance might benefit clinical decision-making because different geometric shapes represent different developmental stepping stones of VMI. Therefore, a new computer-aided measure of VMI (the CAM-VMI) was developed to investigate VMI performance in children with UCP and to identify shapes important for predicting their VMI performance. METHODS: Twenty-eight children with UCP and 28 typically-developing (TD) children were recruited. All participants were instructed to complete the CAM-VMI and Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery-VMI). The test items of the CAM-VMI consisted of nine simple geometric shapes related to writing readiness. Two scores of the CAM-VMI, namely, Error and Effort, were obtained by image registration technique. The performances on the Beery-VMI and the CAM-VMI of children with UCP and TD children were compared by independent t-test. A series of stepwise regression analyses were used to identify shapes important for predicting VMI performance in children with UCP. RESULTS: Significant group differences were found in both the CAM-VMI and the Beery-VMI results. Furthermore, Error was identified as a significant aspect for predicting VMI performance in children with UCP. Specifically, the square item was the only significant predictor of VMI performance in children with UCP. CONCLUSIONS: This study was a large-scale study that provided direct evidence of impaired VMI in school-aged children with UCP. Even when using the less-affected hand, children with UCP could not copy the geometric shapes as well as TD children did. The copied products of children with UCP demonstrated poor constructional accuracy and inappropriate alignment. Furthermore, the predictive model suggested that the constructional accuracy of a copied square is an important predictor of VMI performance in children with UCP.


Asunto(s)
Parálisis Cerebral , Desarrollo Infantil , Niño , Humanos , Desempeño Psicomotor , Computadores , Mano
17.
Hand Clin ; 40(2): 189-198, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38553090

RESUMEN

The profunda artery perforator (PAP) flap provides a good option for hand and upper extremity reconstruction. The reliable quality, caliber, and number of perforators in the posteromedial thigh support large flaps with long pedicles. The PAP flap has been widely used for breast reconstruction, although its use in the extremities has been slower to catch on due to the bulk and thickness of the subcutaneous tissue. The authors discuss evolution of thin flaps and our application of the thin and superthin PAP flap for upper extremity reconstruction.


Asunto(s)
Mamoplastia , Colgajo Perforante , Humanos , Colgajo Perforante/irrigación sanguínea , Arterias/cirugía , Extremidad Superior/cirugía , Mano/cirugía , Estudios Retrospectivos
18.
Hand Clin ; 40(2): 221-228, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38553093

RESUMEN

Soft tissue defects of the hand may result from trauma, infection, vascular disease, and after resection of tumors. Microsurgery has evolved to a stage where it is relatively commonplace today but procedures such as free flaps still incur significant time, manpower, cost, and material resources. The aim of this article is to articulate the specific situations in hand reconstruction when microsurgery is superior to nonmicrosurgical reconstructive options. The benefits of microsurgical reconstruction include a variety of important metrics, such as improved function, better tissue match, less donor site morbidity, and reduced downtime for the patient.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias , Procedimientos de Cirugía Plástica , Humanos , Microcirugia , Mano/cirugía
19.
Hand Clin ; 40(2): 229-236, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38553094

RESUMEN

Vascular malformations in the extremities are a common site of occurrence; arteriovenous malformations (AVMs) are the least frequent of all vascular malformations, estimated at 5% to 20%. The first step in management is to perform a thorough clinical examination. Symptoms are assessed, and staging is performed using the Schobinger classification. Next, ultrasonography and contrast-enhanced computed tomography are used to confirm the diagnosis of AVM and to confirm the extent of the malformation. Surgery is the first-line treatment and reconstruction is performed. In cases where surgery is not feasible, embolization and sclerotherapy may be used to alleviate symptoms.


Asunto(s)
Malformaciones Arteriovenosas , Embolización Terapéutica , Humanos , Malformaciones Arteriovenosas/cirugía , Embolización Terapéutica/métodos , Mano/cirugía , Microcirugia/métodos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Estudios Retrospectivos
20.
Hand Clin ; 40(2): 179-187, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38553089

RESUMEN

The superficial circumflex iliac artery perforator (SCIP) flap is thin, pliable tissue well suited for reconstruction of injuries of the hand and upper extremity. Based upon perforators from the superficial circumflex iliac artery, the SCIP flap has advantages over the traditional groin flap due to reduced need for secondary procedures and improved donor site morbidity This article offers a detailed exploration of the SCIP flap design and technique, its advantages over traditional methods, and its potential applications in reconstructive surgery. Post-operative care and critical points are also discussed, and case examples are provided to guide readers through the intricacies of the technique, emphasizing the surgical skill and precision required for successful implementation.


Asunto(s)
Colgajo Perforante , Procedimientos de Cirugía Plástica , Humanos , Colgajo Perforante/irrigación sanguínea , Arteria Ilíaca/cirugía , Extremidad Superior/cirugía , Mano/cirugía
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