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Classification-based myoelectric control has attracted significant interest in recent years, leading to prosthetic hands with advanced functionality, such as multi-grip hands. Thus far, high classification accuracies have been achieved by increasing the number of surface electromyography (sEMG) electrodes or adding other sensing mechanisms. While many prescribed myoelectric hands still adopt two-electrode sEMG systems, detailed studies on signal processing and classification performance are still lacking. In this study, nine able-bodied participants were recruited to perform six typical hand actions, from which sEMG signals from two electrodes were acquired using a Delsys Trigno Research+ acquisition system. Signal processing and machine learning algorithms, specifically, linear discriminant analysis (LDA), k-nearest neighbors (KNN), and support vector machines (SVM), were used to study classification accuracies. Overall classification accuracy of 93 ± 2%, action-specific accuracy of 97 ± 2%, and F1-score of 87 ± 7% were achieved, which are comparable with those reported from multi-electrode systems. The highest accuracies were achieved using SVM algorithm compared to LDA and KNN algorithms. A logarithmic relationship between classification accuracy and number of features was revealed, which plateaued at five features. These comprehensive findings may potentially contribute to signal processing and machine learning strategies for commonly prescribed myoelectric hand systems with two sEMG electrodes to further improve functionality. [ABSTRACT FROM AUTHOR]

This study focuses on novel design and evaluation of Elastic 50A (EL50) mechanical metamaterials with open-cell patterns for its potential application to lower limb residuum/socket interfaces, specifically that of a transtibial (TT) amputee. Mechanical characteristics, that is, effective Young's modulus (E), was tuned by altering metamaterial porosity, which was experimentally verified. Specifically, pore radius of the unit cell was varied to achieve a range of E -values (0.05–1.71 MPa) for these 3D printed metamaterials. Finite Element Analysis (FEA) was conducted to evaluate pressure distribution across key load-bearing anatomical sites of a TT residuum. Using designed metamaterials for homogeneous liners, pressure profiles were studied and compared with a silicone liner case. Additionally, a custom metamaterial liner was designed by assigning appropriate metamaterials to four load-sensitive and tolerant anatomical sites of the TT residuum. The results suggest that lowest pressure variation (PV), as a measure of pressure distribution levels and potential comfort for amputees, was achieved by the custom metamaterial liner compared to any of the homogeneous liners included in this study. It is envisaged that this work may aid future design and development of custom liners using now commonly available 3D printing technologies and available elastomer materials to maximise comfort, tissue safety and overall rehabilitation outcomes for lower limb amputees. [ABSTRACT FROM AUTHOR]

Background: Cognitive impairment is commonly seen after acute ischemic stroke (AIS). Sedentary behaviors increase the risk of dementia among community dwelling population. Objective: This study aims to investigate the association of sedentary behaviors with poststroke cognitive impairment among older adults with minor AIS. Methods: This cohort study recruited 594 older subjects with minor AIS from three hospitals in China during February 1, 2016, and December 31, 2018. Participants were followed up for two years and the sedentary time per day was self-reported at the end of follow-up. Cognitive functions were assessed by Mini-Mental State Examination (MMSE). Participants were categorized into the high and low sedentary time group according to the median sedentary time of the participants. Results: At two years of follow-up, the long sedentary time group had significantly lower MMSE scores than the short sedentary time group [median, (IQR): 21 (18 to 25) versus 22 (18 to 25), p = 0.368]. The long sedentary time group had a higher speed of cognitive decline than the short sedentary time group. Excessive sedentary time was associated with a higher risk of longitudinal cognitive decline (OR: 2.267, 95% CI: 1.594 to 3.225), adjusting for age, sex, education, body mass index, APOE genotype, comorbidities, symptoms of depression, anxiety, and insomnia, baseline MMSE scores and National Institute of Health Stroke Scale scores, cognitive therapy, and TOAST ischemic stroke subtypes. Conclusions: This study identified a possible link between sedentary behaviors and longitudinal cognitive decline among older patients with minor AIS, suggesting that reducing sedentary time might be helpful for preventing poststroke dementia. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is one of the most common malignancies, and early detection plays a crucial role in enhancing curative outcomes. While colonoscopy is considered the gold standard for CRC diagnosis, noninvasive screening methods of DNA methylation biomarkers can improve the early detection of CRC and precancerous lesions. Methods: Bioinformatics and machine learning methods were used to evaluate CRC‐related genes within the TCGA database. By identifying the overlapped genes, potential biomarkers were selected for further validation. Methylation‐specific PCR (MSP) was utilized to identify the associated genes as biomarkers. Subsequently, a real‐time PCR assay for detecting the presence of neoplasia or cancer of the colon or rectum was established. This screening approach involved the recruitment of 978 participants from five cohorts. Results: The genes with the highest specificity and sensitivity were Septin9, AXL4, and SDC2. A total of 940 participants were involved in the establishment of the final PCR system and the subsequent performance evaluation test. A multiplex TaqMan real‐time PCR system has been illustrated to greatly enhance the ability to detect precancerous lesions and achieved an accuracy of 87.8% (95% CI 82.9–91.5), a sensitivity of 82.7% (95% CI 71.8–90.1), and a specificity of 90.1% (95% CI 84.3–93.9). Moreover, the detection rate of precancerous lesions of this assay reached 55.0% (95% CI 38.7–70.4). Conclusion: The combined detection of the methylation status of SEPT9, SDC2, and ALX4 in plasma holds the potential to further enhance the sensitivity of CRC detection. [ABSTRACT FROM AUTHOR]

Objective: To investigate reliability and changes of in-shoe plantar pressure and shear during walking at three cadences with two insole designs. This was a precursor to the investigation of plantar loading in people with diabetes for potential foot ulcer prevention. Method: A sensorised insole system, capable of measuring plantar pressure and shear at the heel, fifth metatarsal head (5MH), first metatarsal head (1MH) and hallux, was tested with ten healthy participants during level walking. Reliability was evaluated, using intra-class correlation coefficient (ICC), while varying the cadences and insole types. Percentage changes in pressure and shear relative to values obtained at self-selected cadence with a flat insole design were investigated. Results: Mean±standard deviation of maximum pressure, medial–lateral and anterior–posterior shear of up to 380±24kPa, 46±2kPa and –71±4kPa, respectively, were measured. The ICC in ranges of 0.762–0.973, 0.758–0.987 and 0.800–0.980 were obtained for pressure, anterior–posterior and medial–lateral shear, respectively. Opposite anterior–posterior shear directions between 5MH and 1MH (stretching), and between 1MH and hallux (pinching) were observed for some participants. Increasing cadence increased pressure and anterior–posterior shear (by up to +77%) but reduced medial–lateral shear at the heel and hallux (by up to –34%). Slower cadence increased anterior–posterior shear (+114%) but decreased medial–lateral shear (–46%) at the hallux. The use of a flexible contoured insole resulted in pressure reduction at the heel and 5MH but an increase in anterior–posterior shear at the heel (+69%) and hallux (+75%). Conclusion: The insole system demonstrated good reliability and is comparable to reported pressure-only systems. Pressure measurements were sensitive to changes in cadence and insole designs in ways that were consistent with the literature. However, our plantar shear showed localised shear changes with cadences and insoles for the first time, as well as stretching and pinching effects on plantar tissue. This opens new possibilities to investigate plantar tissue viability, loading characteristics and orthotic designs aimed towards foot ulcer prevention. [ABSTRACT FROM AUTHOR]

Fluctuations in residuum volume during daily activities are known to occur in lower-limb amputees. This can cause frequent changes to fit, which cannot be accommodated by commonly-used prosthetic sockets. The real-time effects, if any, of these minor socket fit changes on interface biomechanics have not been studied extensively. Amputees commonly use different layers of socks to accommodate frequent volume fluctuations, enabling adjustment of socket fit. We, thus, altered socket fit levels via addition/removal of sock layers to a transtibial amputee who habitually-donned two-sock layers to mimic relatively looser and tighter socket fits. Interface pressure and shear sensors were placed at known prominent load-bearing sites of the transtibial residuum/socket interface, i.e., patellar tendon (PT), popliteal fossa (PF), and anterior–distal (AD) end, to measure real-time biomechanical interactions during standing and level walking. Although socket fit level was only slightly modified, changes in interface pressure and shear across anatomical sites were still observed. Tighter fit corresponds to notable pressure reduction at AD during early stance and pressure increase at PT during terminal stance due to the residuum being pushed up. Shear-to-pressure ratios were used to assess comfort, while pressure– and shear–time integrals were used to assess tissue health. We observed more notable changes at tissue sites (e.g., AD and PF). Combined evaluation of pressure and shear, including shear-to-pressure ratio and time integrals, may offer insight for residuum care. [ABSTRACT FROM AUTHOR]

Pressure coupled with shear stresses are the critical external factors for diabetic foot ulceration assessment and prevention. To date, a wearable system capable of measuring in-shoe multi-directional stresses for out-of-lab analysis has been elusive. The lack of an insole system capable of measuring plantar pressure and shear hinders the development of an effective foot ulcer prevention solution that could be potentially used in a daily living environment. This study reports the development of a first-of-its-kind sensorised insole system and its evaluation in laboratory settings and on human participants, indicating its potential as a wearable technology to be used in real-world applications. Laboratory evaluation revealed that the linearity error and accuracy error of the sensorised insole system were up to 3% and 5%, respectively. When evaluated on a healthy participant, change in footwear resulted in approximately 20%, 75% and 82% change in pressure, medial–lateral and anterior–posterior shear stress, respectively. When evaluated on diabetic participants, no notable difference in peak plantar pressure, as a result of wearing the sensorised insole, was measured. The preliminary results showed that the performance of the sensorised insole system is comparable to previously reported research devices. The system has adequate sensitivity to assist footwear assessment relevant to foot ulcer prevention and is safe to use for people with diabetes. The reported insole system presents the potential to help assess diabetic foot ulceration risk in a daily living environment underpinned by wearable pressure and shear sensing technologies. [ABSTRACT FROM AUTHOR]

We explore the effect of initial public offering (IPO) capital allocation on corporate innovation. We document that IPOs enhance corporate innovation through allocation of internal capital to innovative projects. While political connections moderate the IPO‐innovation relation in that connected firms allocate less IPO capital to innovative projects and are more likely to reallocate their resource from innovative to non‐innovative projects. Resource allocation to innovative projects results in better post‐IPO performance, especially in non‐connected firms. Overall, this study identifies intra‐firm capital allocation as an important factor that contribute to firm innovation and the distortion of resource allocation linked to political ties. [ABSTRACT FROM AUTHOR]

The study was designed to establish a biomechanical assessment platform for the lower limb residuum/socket interface as a function of duration and speed of movement. The approach exploits an interface sensor which measures multi-directional stresses at the interface. The corresponding interface coupling motion was assessed using a 3D motion capture system. A longitudinal study, involving a trans-femoral amputee, was conducted with nine repeated level walking sessions over a 12-month period. The effect of walking speed on interface biomechanics was also assessed. Interface peak pressures and shear stresses in the range of 55-59 kPa and 12-19 kPa were measured, respectively, over all sessions in the 12 months study period at the posterior-proximal location of the residuum. The peak pressure and longitudinal shear values were found to fluctuate approximately 11% and 40% as against its maximum value, respectively, over 12 months. In addition, up to 12° of angular coupling and up to 28 mm of pistoning were recorded over a gait cycle, which was found to change by 29% and 45% respectively over the study period. The variation in walking speed, by altering self-selected cadence, resulted in changes of pressure and shear stresses at mid-stance of the gait cycle. In particular, as compared with self-selected cadence, for fast speed, peak pressure and peak longitudinal shear stress decreased by 5% and 33%, respectively. For slow speed, peak pressure and peak longitudinal shear stress increased by 7% and 17%, respectively. The corresponding angular and pistoning revealed a variation of up to 29% and 45%, respectively. This biomechanical assessment approach shows promise in the quantitative assessment of interface kinematics and kinetics for lower limb prosthetics, the usage of which could assist the clinical assessment of prosthetic socket fit. [ABSTRACT FROM AUTHOR]

Objective. To explore the efficiency of continuity of care plus whole process psychological intervention for lung cancer patients undergoing chemotherapy. Methods. A total of 130 patients who have lung cancer undergoing chemotherapy admitted to our hospital from 2019 to 2021 were recruited and assigned via different intervention methods (1 : 1) to receive either continuity of care plus whole process psychological intervention (observation group) or routine nursing (control group). Outcome measures included psychological state, treatment compliance, quality of life, and nursing satisfaction. Results. Continuity of care plus whole process psychological intervention was associated with significantly lower Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA) scores versus routine care. The patients given combined nursing showed higher self-esteem scores versus those given routine care. Continuity of care plus whole process psychological intervention also resulted in significantly lower cancer-related fatigue scores and higher treatment compliance versus routine care. Patients given continuity of care plus whole process psychological intervention had a better quality of life and higher nursing satisfaction versus those given routine care (P < 0.05). Conclusions. Continuity of care plus whole process psychological intervention can effectively mitigate the negative emotions of lung cancer patients, alleviate cancer-related fatigue, improve treatment compliance, and boost the life quality of patients. [ABSTRACT FROM AUTHOR]

Reductive cleavage of aromatic and benzylic C–O bonds by chromium catalysis is reported. This deoxygenative reaction was promoted by low-cost CrCl2 precatalyst combined with poly(methyl hydrogen siloxane) as the mild reducing agent, providing a strategy in forming reduced motifs by cleavage of unactivated C–O bonds. A range of functional groups such as bromide, chloride, fluoride, hydroxyl, amino, and alkoxycarbonyl can be retained in the reduction. [ABSTRACT FROM AUTHOR]

Frustration is often seen as negative, but as to whether it may have a positive impact on the individual is still undecided. This research was conducted to explore the influence of frustration on altruistic tendency and altruistic level in college students (17–21 years old). By presenting a highly difficult task combined with negative feedback, we effectively induced frustration in Experiment 1 (n = 70). By assessing the donation behavior of participants (n = 54) in a real-life scenario following the experimental manipulation of frustration, we examined the relationship between frustration and altruism in Experiment 2. Results showed that frustrating situations could, on some level, improve altruistic behavior [ t (8.834) = 3.013, p = 0.015]. More specifically, among participants who donated, the amount donated was higher in the frustration group compared to the control (fulfillment) group; the proportion of people who donated did not differ by group. [ABSTRACT FROM AUTHOR]

We argue and provide evidence that instead of playing a monitoring role, venture capital (VC) investors collude with controlling shareholders in the IPO process of Chinese non‐state‐owned enterprises (non‐SOEs). We show that VC‐backed IPOs' applications are more likely to be approved by regulators, especially in firms with excess control rights, but have worse post‐IPO performance. Through investing in firms with excess control rights, VC investors are able to make higher exit returns. We further document that VC investors' role in the IPO process is stronger when they have political connections, hold higher ownership, and when they make pre‐IPO investment. [ABSTRACT FROM AUTHOR]

Experimental investigations were conducted to explore the thermal and exergy efficiency of Fe3O4‐H2O nanofluids in a corrugated tube. Some influences of the twisted turbulator, horizontal magnetic fields (B = 6mT, 12mT, and 18mT), particle mass fractions (ω = 0.1, 0.3, and 0.5 wt%) as well as Re numbers (800–12,000) were analyzed. The experimental results exhibited that the heat transfer capacity of nanofluids intensifies with the increment of mass fraction but weakens with the increase of magnetic flux density. For the same external conditions, the heat transfer capability of the corrugated tube with an inserted twisted turbulator is obviously stronger than that without the turbulator. The resistance coefficient can be augmented by the increasing mass fraction and horizontal magnetic field. In addition, the thermal efficiency R3 and the exergy efficiency were adopted to estimate the comprehensive performance of each working condition. It could be found that the increased mass fraction and reduced magnetic flux density cause an increasing trend on the thermal efficiency. Also, it was obtained that the exergy efficiency of working fluids is intensified under identical pumping power. [ABSTRACT FROM AUTHOR]

Objectives: Gamma glutamyl-transpeptidase (GGT) has been shown as a prognostic marker in many cancers. The aim of this study was to explore whether serum GGT could predict tumor recurrence in patients with liver-confined colorectal cancer liver metastases (CRCLM) undergoing R0 resection. Methods: We reviewed patients who had underwent liver surgery for CRCLM. Patients with liver-only metastases that underwent R0 resection were included. Pre-operative serum GGT were classified into either high or low using a cut-off value of 33 U/L for female and 51 U/L for male. Relapse-free survival (RFS) was compared in relation to GGT and other clinicopathological factors. Results: Of the 350 patients included, 108 (30.9%) had a high serum GGT. Patients with metachronous liver metastases, number of metastases ⩾2, size of the largest metastasis ⩾3 cm, or a history of neoadjuvant chemotherapy had a higher GGT level (p = 0.001, 0.027, 0.001, and 0.002, respectively). In survival analyses, patients with a high GGT had a shorter RFS than those with a low GGT, with a median RFS of 11.8 versus 30.3 months (p < 0.001). RFS was also associated with the number of metastases, size of the largest metastasis and the delivery of neoadjuvant chemotherapy. In multivariate analysis, GGT remained an independent prognostic factor of RFS. Conclusions: Our study demonstrates that the serum GGT level before liver surgery is an adverse prognostic factor of RFS for patients with liver-confined CRCLM. [ABSTRACT FROM AUTHOR]