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Highlights Bulk molding compound (BMC) manufactured using fiber reinforced polymers (FRPs) has attracted extensive attention and is widely used because of its capability to fabricate structures with complex shapes. This study investigated the effects of aging on the mechanical properties of BMC composites made using an epoxy matrix and discontinuous carbon fibers of varying lengths. Tensile, compressive, and flexural tests were conducted. The results showed that longer fibers did not necessarily increase the moduli and strengths of BMC composites due to stress concentrations resulting from the curling and entanglement of the longer fibers. When aged, BMC composites using shorter carbon fibers exhibited more significant reductions in moduli and strengths due to higher void contents, resulting in more severe matrix epoxy degradation. When comparing epoxy and BMC, BMC experienced greater reductions in moduli and strengths even though carbon fiber, a type of artificial fiber, should be less affected by aging. This is because aging not only degraded the matrix epoxy but also affected the adhesion between the fibers and the matrix, leading to a larger displacement of the fibers, resulting in a more severe reduction in the mechanical properties of the BMC composites. BMC composites were manufactured using epoxy and discontinuous carbon fibers. Longer fibers did not necessarily increase strengths due to entanglement. BMC using shorter fibers had more voids and hence degraded more severely. BMC showed greater strength reductions than epoxy due to matrix degradation. Degradation of matrix epoxy affected the adhesion between fibers and matrix. [ABSTRACT FROM AUTHOR]

Powered ankle prostheses have been proven to improve the walking economy of people with transtibial amputation. All commercial powered ankle prostheses that are currently available can only perform one-degree-of-freedom motion in a limited range. However, studies have shown that the frontal plane motion during ambulation is associated with balancing. In addition, as more advanced neural interfaces have become available for people with amputation, it is possible to fully recover ankle function by combining neural signals and a robotic ankle. Accordingly, there is a need for a powered ankle prosthesis that can have active control on not only plantarflexion and dorsiflexion but also eversion and inversion. We designed, built, and evaluated a two-degree-of-freedom (2-DoF) powered ankle–foot prosthesis that is untethered and can support level-ground walking. Benchtop tests were conducted to characterize the dynamics of the system. Walking trials were performed with a 77 kg subject that has unilateral transtibial amputation to evaluate system performance under realistic conditions. Benchtop tests demonstrated a step response rise time of less than 50 milliseconds for a torque of 40 N·m on each actuator. The closed-loop torque bandwidth of the actuator is 9.74 Hz. Walking trials demonstrated torque tracking errors (root mean square) of less than 7 N·m. These results suggested that the device can perform adequate torque control and support level-ground walking. This prosthesis can serve as a platform for studying biomechanics related to balance and has the possibility of further recovering the biological function of the ankle–subtalar–foot complex beyond the existing powered ankles. [ABSTRACT FROM AUTHOR]

Aim: To investigate the efficacy and safety of beinaglutide as an adjunct to lifestyle intervention among non‐diabetic Chinese individuals with overweight or obesity. Methods: This multicentre, randomized, double‐blind, placebo‐controlled trial (ChiCTR1900023428) included 427 Chinese adults with a body mass index of 28 kg/m2 or higher (obesity) or 24‐27.9 kg/m2 (overweight) with weight‐related complications. Patients were randomized in a 2:1 ratio to receive 0.2 mg of beinaglutide (subcutaneous) thrice daily or placebo for 16 weeks. Co‐primary endpoints were body weight change and the proportion of patients with a weight reduction of 5% or more. Results: Mean body weight change from baseline to week 16 was −6.0% and −2.4% in the beinaglutide (n = 282) and placebo (n = 138) groups, respectively; the mixed model repeated measures difference was −3.6% (95% confidence interval: −4.6% to −2.6%; P <.0001). At week 16, more beinaglutide‐treated patients achieved a weight reduction of 5% or more (58.2% vs. 25.4% [placebo], odds ratio: 4.4; P <.0001) and of 10% or more (21.3% vs. 5.1% [placebo], odds ratio: 5.5; P <.0001). Beinaglutide also resulted in greater waist circumference reduction (difference: −1.81 cm; P <.01). The weight regain rate 12 weeks after beinaglutide treatment was 0.78%. Nausea (transient and mild‐to‐moderate) was the most common adverse event in the beinaglutide group (49.3% vs. 7.1% [placebo]). More patients receiving beinaglutide discontinued treatment because of adverse events (5.9% vs. 0.7% [placebo]). Pancreatitis or an increased resting heart rate was not observed in the beinaglutide group. Conclusion: Beinaglutide combined with lifestyle intervention resulted in significant and clinically meaningful weight reduction with good tolerance in non‐diabetic Chinese individuals with overweight or obesity. [ABSTRACT FROM AUTHOR]

In recent years, exterior-rotor brushless DC motors have become increasingly popular in robotics applications due to their compact shape and high torque density. However, these motors were originally used for continuous operation in drones. For applications such as exoskeletons, prostheses, or legged robots, short bursts of high power are often required. Unfortunately, vendors do not typically provide data on the motors' performance under these conditions. This paper presents experimental data on the torque–speed relationship, efficiency, and thermal responses of one of the most widely used outrunner-type brushless motors across its full operating range, including high-power short-duration operation. The results of this study can inform the selection and design of actuators for a range of robotics applications, particularly those that require high power output for brief periods of time. [ABSTRACT FROM AUTHOR]

This work used short carbon fibers (SCFs) of different lengths to manufacture epoxy bulk mold compound (BMC) composites. Drop-weight-impact tests were performed on the intact carbon-fiber-reinforced-polymers (CFRPs) laminates to generate artificial damage. The damaged CFRP laminates were then repaired using the SCF-BMC composites. Compression after impact (CAI) tests were conducted to measure the compressive strength of the repaired laminates. Tensile properties and compressive properties of the SCF-BMC composites were also measured. The results show that 48-mm carbon fibers result in the largest tensile modulus, tensile strength, and compressive strength, while 12-mm carbon fibers result in the largest compressive modulus. CAI test results show that the compressive strength of the repaired laminate can be restored to 80.3% of that of the undamaged laminate. Therefore, SCF-BMC composites significantly contribute to repairing damaged composite laminates. [ABSTRACT FROM AUTHOR]

This study implemented the measurement results and administrative information obtained from the hole plate into the Digital Calibration Certificate (DCC). The DCC comprises three parts: Norms and Standards, Hierarchical Structure, and XML as Exchange Format. DCCs play a significant role in the field of metrology and statistics by ensuring data interoperability, correctness, and traceability during the conversion and transmission process. The hole plate is a length standard used for two-dimensional geometric error measurements. We evaluated the accuracy of the high-precision coordinate measuring machine (CMM) in measuring a hole plate and compared the measurement error results obtained from the hole plate with those of the laser interferometer, autocollimator, and angle square. The results show that the maximum difference in linear error is −0.30 μm, the maximum difference in angle error is −0.78″, and the maximum difference in squareness error is 4.54″. The XML is designed for machine-readability and is modeled and edited using the XMLSpy 2022 software, which is based on information published by PTB. The administrative management and measurement results tasks are presented in PDF format, which is designed for human-readability and ease of use. Overall, we implemented the measurement results and information obtained from the hole plate into the DCC. [ABSTRACT FROM AUTHOR]