Does Radial Extracorporeal Shockwave Therapy Applied to the Achilles Tendon Influence Ankle Functionality?

This study aimed to determine the effectiveness of radial extracorporeal shockwave therapy (rESWT) in enhancing ankle function in patients with Achilles tendon injuries. The choice of rESWT was based on previous success in the treatment of musculoskeletal conditions. The study involved an intervention group that received rESWT, and a control group that received sham therapy. The results revealed that rESWT led to significant improvements in single-leg vertical jump (d = 0.55, p < 0.05), indicating enhanced power generation and ankle functionality that were not observed in the control group. Additionally, the therapy resulted in increased ankle mobility, as observed by improvements in plantar flexion and heel-rise tests. Interestingly, these functional gains were not accompanied by changes in the Achilles tendon stiffness, suggesting that the benefits of rESWT may be more functional than structural. This study highlights rESWT as a promising tool for rehabilitation, particularly following Achilles tendon injuries. The study concluded that, although rESWT appears to improve certain aspects of ankle function, further studies with a larger and more diverse population over a longer period are necessary to confirm these findings and establish comprehensive treatment protocols.

Timoshenko-Ehrenfest Beam-Based Reconfigurable Elastic Metasurfaces for Multifunctional Wave Manipulation.

Herein, a Timoshenko-Ehrenfest beam-based reconfigurable elastic metasurface is introduced that can perform multifunctional wave phenomena within a single substrate, featuring high transmission in the ultrabroadband frequency range. Conventional elastic metasurfaces are typically limited to specific purposes and frequencies, thereby imposing significant constraints on their practical application. The approach involves assembly-components with various geometries on a substrate for reconfigurability, enabling to easily control and implement multifunctional wave phenomena, including anomalous-refraction, focusing, self-acceleration, and total-reflection. This is the first study on elastic metasurfaces to theoretically analyze the dispersion relation based on the Timoshenko-Ehrenfest beam theory, which considers shear deformations and rotational inertia. The analytical model is validated by demonstrating an excellent agreement with numerical and experimental results. The findings include full-wave harmonic simulations and experimentally visualized fields for measuring various wave modulations. Furthermore, the practicality of the system is verified by significantly enhancing the piezoelectric energy harvesting performance within the focusing configuration. It is believed that the reconfigurable elastic metasurface and analytical model based on the Timoshenko-Ehrenfest beam theory have vast applications such as structural health monitoring, wireless sensing, and Internet of Things.

Ultrasonic barrier-through imaging by Fabry-Perot resonance-tailoring panel.

Imaging technologies that provide detailed information on intricate shapes and states of an object play critical roles in nanoscale dynamics, bio-organ and cell studies, medical diagnostics, and underwater detection. However, ultrasonic imaging of an object hidden by a nearly impenetrable metal barrier remains intractable. Here, we present the experimental results of ultrasonic imaging of an object in water behind a metal barrier of a high impedance mismatch. In comparison to direct ultrasonic images, our method yields sufficient object information on the shapes and locations with minimal errors. While our imaging principle is based on the Fabry-Perot (FP) resonance, our strategy for reducing attenuation in our experiments focuses on customising the resonance at any desired frequency. To tailor the resonance frequency, we placed an elaborately engineered panel of a specific material and thickness, called the FP resonance-tailoring panel (RTP), and installed the panel in front of a barrier at a controlled distance. Since our RTP-based imaging technique is readily compatible with conventional ultrasound devices, it can realise underwater barrier-through imaging and communication and enhance skull-through ultrasonic brain imaging.

Effects of SKCPT on Osteoarthritis in Beagle Meniscectomy and Cranial Cruciate Ligament Transection Models.

Osteoarthritis (OA) affects >500 million people globally, and this number is expected to increase. OA management primarily focuses on symptom alleviation, using non-steroidal anti-inflammatory drugs, including Celecoxib. However, such medication has serious side effects, emphasizing the need for disease-specific treatment. The meniscectomy and cranial cruciate ligament transection (CCLx)-treated beagle dog was used to investigate the efficacy of a modified-release formulation of SKI306X (SKCPT) from Clematis mandshurica, Prunella vulgaris, and Trichosanthes kirilowii in managing arthritis. SKCPT's anti-inflammatory and analgesic properties have been assessed via stifle circumference, gait, incapacitance, histopathology, and ELISA tests. The different SKCPT concentrations and formulations also affected the outcome. SKCPT improved the gait, histopathological, and ELISA OA assessment parameters compared to the control group. Pro-inflammatory cytokines and matrix metalloproteinases were significantly lower in the SKCPT-treated groups than in the control group. This study found that SKCPT reduces arthritic lesions and improves abnormal gait. The 300 mg modified-release formulation was more efficacious than others, suggesting a promising approach for managing OA symptoms and addressing disease pathogenesis. A high active ingredient level and a release pattern make this formulation effective for twice-daily arthritis treatment.

Comparison of physical function, proprioception, muscle strength, postural balance, and walking in older women with and without total knee arthroplasty.

The benefit of total knee arthroplasty (TKA) is that it alleviates pain caused by osteoarthritis; however, other postoperative effects on physical function are unclear. This study aimed to investigate the differences in physical function, proprioception, muscle strength, postural balance, and walking in older women with and without TKA. A total of 36 participants were included in this study; the TKA group comprised older women who underwent TKA (n = 18) and the non TKA group comprised older women who did not undergo TKA (n = 18). All the participants were evaluated for physical function, proprioception, muscle strength, postural balance, and walking. The outcome measures were compared between the 2 groups using an independent t test. Correlations were assessed using Pearson correlation coefficients. Participants in the TKA group had significantly reduced physical function, postural balance, and walking ability compared with those in the non TKA group (P < .05). In the TKA group, physical function was statistically correlated with proprioception, postural balance, and walking (P < .05); in particular, it had a strong correlation with proprioception (R > .60). In the non TKA group, postural balance was significantly associated with muscle strength and walking (P < .05). In particular, it was strongly correlated with walking (R > .90). This study demonstrated that older women undergoing TKA need to actively perform interventions to improve physical function, postural balance, and walking compared with older women with osteoarthritis.

Tailoring Two-Dimensional Matter Using Strong Light-Matter Interactions.

The shaping of matter into desired nanometric structures with on-demand functionalities can enhance the miniaturization of devices in nanotechnology. Herein, strong light-matter interaction was used as an optical lithographic tool to tailor two-dimensional (2D) matter into nanoscale architectures. We transformed 2D black phosphorus (BP) into ultrafine, well-defined, beyond-diffraction-limit nanostructures of ten times smaller size and a hundred times smaller spacing than the incident, femtosecond-pulsed light wavelength. Consequently, nanoribbons and nanocubes/cuboids scaling tens of nanometers were formed by the structured ablation along the extremely confined periodic light fields originating from modulation instability, the tailoring process of which was visualized in real time via light-coupled in situ transmission electron microscopy. The current findings on the controllable nanoscale shaping of BP will enable exotic physical phenomena and further advance the optical lithographic techniques for 2D materials.

Greenhouse gas reduction and economic cost of technologies using green hydrogen in the steel industry.

Reducing greenhouse gas (GHG) emissions from the steel industry is one of the top priorities for mitigating climate change. Although hydrogen has been considered as a key element to accomplish this task, the effects of various hydrogen-using technologies in steel mills have not been analysed and compared to each other. This paper quantitatively analysed the greenhouse gas reduction in steel mills by the use of hydrogen produced from electrolysis with renewable electricity. The four following methods of using green hydrogen were proposed and analysed: 1) use of hydrogen directly in the hydrogen steelmaking process, 2) use of hydrogen to convert byproduct gases produced from steel mills into methanol, 3) use hydrogen to convert the byproduct gases into methane, and 4) sell hydrogen to the hydrogen station and use of oxygen, another product of electrolysis, to reduce the use of air separating unit in steel mills. Not only the greenhouse gas reduction benefits but also the economic cost of these four methods were evaluated. As those results can vary according to country, the economic cost and GHG reduction benefits were determined for the representative steel-producing countries of China, India, Japan, the United States, Russia, South Korea, and Germany. The economic cost was evaluated not only for the present (2020) but also for the future (∼2040) because these methods are more likely to be implemented in the future. Currently, in the representative steel-producing countries, Method 1 was analysed to have the largest GHG reduction among the four methods; but it also showed the largest cost because of its large capital expenditures and electricity cost. Method 2, which converts the byproduct gases into methanol, was shown to offer larger GHG reduction and smaller economic cost than Method 3, which converts the byproduct gases into methane. Comparing Methods 1 and 2, Method 2 offered smaller GHG reduction but a much smaller economic cost than Method 1. Although the cost of Method 4 is currently the smallest, the economic cost of Method 2 is predicted to become lower than that of Method 4 in the future, near 2030, because the future prices of hydrogen and the CO2 allowance are expected to decrease and increase, respectively. These results can be utilized when steelmaking country or steelmaking company make their decision on how to decrease the GHG emissions by using green hydrogen.

Effects of lumbar joint mobilization on trunk function, postural balance, and gait in patients with chronic stroke: A randomized pilot study.

BACKGROUND: Patients with stroke have hypomobility in the facet joint of affected side. Lumbar joint mobilization could be used to maintain function and mobility of the joints. OBJECTIVE: This study aimed to investigate the effects of lumbar joint mobilization on trunk function, postural balance, and gait in patients with stroke. METHODS: Thirty patients with stroke were randomly assigned to two groups. Lumbar joint mobilization was provided for 15 min, 5 times a week for 6 weeks to patients who were allocated into the experimental group. Patients who were allocated into the control group received a sham intervention. Trunk function (trunk impairment scale), postural balance (weight distribution, Berg balance scale, and timed up and go test), and walking (10 m walk test, functional gait assessment, step length, and stride length) were evaluated before and after the experiment for all the patients. RESULTS: Lumbar joint mobilization significantly improved trunk function, postural balance, and gait compared with pre-test values in the experimental group (P< 0.05). Significant differences were seen in trunk function, postural balance, and walking between the two groups (P< 0.05). CONCLUSION: Lumbar joint mobilization might be an effective intervention for trunk function, postural balance, and walking in patients with stroke.

Correlating multimode strain and electrode configurations for high-performance gradient-index phononic crystal-based piezoelectric energy harvesting.

A gradient-index phononic crystal (GRIN PnC) capable of manipulating wave propagation can serve as an excellent input wave energy focusing platform for amplifying energy harvesting power generation. However, despite its remarkable focusing capability, the finite wavelength of the propagating elastic waves in the focal area causes voltage cancellation inside a piezoelectric element under multimode strains having opposite directions; this limits the capacity of the GRIN PnC-based energy harvesting system. This study demonstrates a rational electrode configuration for a piezoelectric energy harvesting (PEH) device that can maximize the performance of a given GRIN PnC platform. The multimode strain analysis experimentally performed on the PEHs distributed over the focusing area confirms that the patterned electrode PEH configuration is the most effective in alleviating strain and voltage cancellation while efficiently transferring the focused elastic wave energy. Furthermore, a proper combination of electrical connections between the patterned electrodes substantially increases the piezoelectric potential across the ceramic by maximizing the strain difference. The simultaneous tailoring of the piezoelectric ceramic composition and the electrode configuration leads to a maximum power generation of 7.06 mW even under off-resonance conditions, the largest ever reported in elastic wave energy harvesting.

Efficacy of radial extracorporeal shockwave therapy in rehabilitation following arthroscopic rotator cuff repair: A STROBE compliant study.

Rotator cuff tear is a common cause of shoulder pain and disability. Arthroscopic rotator cuff repair (ARCR) is performed to treat a torn tendon. Postoperative joint immobilization is essential, but it is a problem that needs to be addressed in the rehabilitation process. This study aimed to evaluate the effects of radial extracorporeal shock wave therapy (rESWT) in patients who underwent ARCR and required active movement after the immobilization period. This study was an open-label, prospective, single-arm trial of 30 inpatients aged >18 years who underwent ARCR. A total of 6 rESWT sessions, along with the conventional rehabilitation program for ARCR patients, were provided at the hospital's sports rehabilitation center for 2 weeks. The application sites of rESWT are periscapular muscles (supraspinatus, infraspinatus, teres minor, and rhomboid). Evaluations were conducted 3 time points-baseline, immediately after the first session of rESWT, and after 2 weeks of intervention. The outcome measures were the numeric pain rating scale for pain, and shoulder flexion, scaption flexion, abduction, horizontal adduction, external rotation, and internal rotation for shoulder range of motion. For shoulder function, disabilities of the arm, shoulder and hand, shoulder pain and disability index, and simple shoulder test were used, and muscle strength was expressed by grip strength. supraspinatus and infraspinatus evaluated thickness, tone, and stiffness. The muscle strength (95% CI, -3.554 to -0.073) and supraspinatus tone (P = .017) showed significant changes immediately after the first session of rESWT. Further, there was significant improvement in ROM (P < .01); shoulder function (P < .01); and muscle strength (95% CI, -3.561 to -0.625), supraspinatus stiffness (95% CI, -67.455 to -26.345), and infraspinatus stiffness (P = .045) after 2 weeks of intervention. However, muscle thickness and tone were significantly improved only in supraspinatus (P = .044, P = .040). Rehabilitation with radial extracorporeal shock wave therapy additionally applied to the periscapular muscles in patients who started active movement in rehabilitation after arthroscopic rotator cuff repair is effective for shoulder function and muscle properties (muscle strength, thickness, tone, and stiffness). However, a randomized controlled trial is needed to further assess the effects of radial extracorporeal shock wave therapy alone.

Highly tunable low frequency metamaterial cavity for vibration localization.

Metamaterial cavity has gathered much attention recently due to its capability of localizing vibration energy. Despite the active research, however, there are still big technical challenges not solved yet. Especially, there has been no approach to maximize the wave localization performance of metamaterial cavity; therefore, there has been a possibility that obtained cavity mode does not show sufficiently high performance. Also, there is a tunability issue that whole metamaterials should be re-designed to tune the cavity frequency. Here, we present the metamaterial cavity system that can control its cavity mode frequency from 589 to 2184 Hz by adjusting the cavity length from 140 to 60 mm without re-designing the whole metamaterial based on the broad bandgap. Also, the performance of the obtained cavity mode can be improved by adjusting the length of the side beam attached to the metamaterial; the displacements are amplified more than 18-110 times. Consequently, one may easily obtain the highly localized vibration energy at the desired frequency by adjusting two geometric parameters based on the proposed metamaterial cavity system. Numerical and experimental supports are provided to validate our new metamaterial cavity system. This metamaterial cavity system is expected to provide a guideline for localizing vibration energy in various applications, such as energy harvesting, sensing or vibration dissipation.

L-shape triple defects in a phononic crystal for broadband piezoelectric energy harvesting.

This study proposes a phononic crystal (PnC) with triple defects in an L-shape arrangement for broadband piezoelectric energy harvesting (PEH). The incorporation of defects in PnCs has attracted significant attention in PEH fields owing to properties such as energy localization and amplification near the defect. Several studies have been conducted to enhance output electric power of PnC-based PEH systems with single defects. However, it is susceptible to the limitations of narrow bandwidth. Recently, double-defect-incorporated systems have been proposed to widen the PEH bandwidth via defect-band splitting. Nevertheless, the PEH performance rapidly decreases in the frequency range between the split defect bands. The limitations of single- and double-defect-incorporated systems can be resolved by the incorporation of the proposed design concept, called the L-shape triple defects in a PnC. The isolated single defect at the top vertex of the letter 'L' compensates for the limitations of double-defect-incorporated systems, whereas the double defects at the bottom vertices compensate for the limitations of the single-defect-incorporated systems. Hence, the proposed design can effectively confine and harvest elastic-wave energy over broadband frequencies while enhancing the application of single and double defects. The effectiveness of the proposed design concept is numerically validated using the finite element method. In the case of a circular hole-type PnC, it is verified that the PnC with L-shape triple defects broadens the bandwidth, and improves the output voltage and electric power compared with those of single- and double-defect-incorporated systems. This study expands the design space of defect-incorporated PnCs and might shed light on other engineering applications of the frequency detector and elastic wave power transfer.

Extremely low frequency wave localization via elastic foundation induced metamaterial with a spiral cavity.

We proposed a metamaterial which exhibits elastic wave localization at extremely low frequencies. First, we opened an extremely low bandgap via elastic foundations. Subsequently, we investigated wave localization by imposing normal defect, which is widely used to capture waves in conventional wave localization systems. However, there were limitations: wave localization was not achieved when a weak bandgap is generated, and the operating frequency of localization is still in the upper part of the bandgap. To overcome wave localization via the normal defect, we proposed a novel metamaterial with a spiral cavity which can tune the resonating frequency depending on the length of the spiral path. By imposing on the spiral cavity inside the elastic foundation-induced metamaterial, we can shift the resonating frequency of the cavity down. Finally, we carried out wave simulations, not only to support the previous eigenfrequency study for the supercell, but also to verify that the finite-size metamaterial can also achieve wave localization at the extremely low frequencies. Through wave simulations, we could observe wave localization even at 77.3 Hz, which is definitely the lower part of the extremely low bandgap.

Autoencoder-based detection of near-surface defects in ultrasonic testing.

Defect detection during pulse-echo ultrasonic testing (UT) is challenging when defects are located in a dead zone where the echoes from the defects are overshadowed by disturbances from the initial ringing signal of the UT transducer. The time-gate method is one of the most widely used approaches in UT to filter out such unwanted components, but defects in the dead zone are virtually impossible to detect using conventional methods. This paper proposes an autoencoder-based end-to-end ultrasonic testing method to detect defects within the dead zone of a transducer. The autoencoder is designed to predict the normal behavior of ultrasonic signals including disturbances, thus enabling the identification of even subtle deviations made by defects. To advance the performance of the autoencoder further with a limited amount of training data, a two-step training procedure is presented, involving training using pure normal signals measured from a defect-free specimen and re-training using pseudo-normal samples identified by the autoencoder with a smart thresholding strategy. This two-step procedure enables us to develop an adaptive autoencoder model that can be effectively employed to process the newly measured ultrasonic signals. For a demonstration of the proposed method, UT-based B-scan inspections of aluminum blocks with near-surface defects are conducted. The results suggest that the proposed method outperforms the conventional gate-based inspection approach with regard to its ability to identify the sizes and locations of near-surface defects.

Double defects-induced elastic wave coupling and energy localization in a phononic crystal.

This study aims to investigate elastic wave localization that leverages defect band splitting in a phononic crystal with double defects through in-depth analysis of comparison of numerical and experimental results. When more than one defect is created inside a phononic crystal, these defects can interact with each other, resulting in a distinctive physical phenomenon from a single defect case: defect band splitting. For a phononic crystal consisting of circular-hole type unit cells in a thin aluminum plate, under A0 (the lowest antisymmetric) Lamb waves, both numerical simulations and experiments successfully confirm the defect band splitting phenomenon via frequency response functions for the out-of-plane displacement calculated/measured at the double defects within a finite distance. Furthermore, experimental visualization of in-phase and out-of-phase defect mode shapes at each frequency of the split defect bands is achieved and found to be in excellent agreement with the simulated results. Different inter-distance combinations of the double defects reveal that the degree of the defect band splitting decreases with  the increasing distance due to weaker coupling between the defects. This work may shed light on engineering applications of a multiple-defect-introduced phononic crystal, including broadband energy harvesting, frequency detectors, and elastic wireless power transfer.

The relationship between sitting balance, trunk control and mobility with predictive for current mobility level in survivors of sub-acute stroke.

OBJECTIVE: To investigate the relationship between sitting balance, trunk control, and mobility, as well as whether the sitting balance and trunk control can predict mobility level in sub-acute stroke survivors. METHODS: This is a observational and cross-sectional study. Fifty-five hemiplegic stroke survivors were participated in this study. The Timed Up and Go Test (TUG) was used to estimate mobility, and the Sitting Balance Scale (SBS) was used to examining sitting balance. The Trunk Impairment Scale (TIS), Trunk Control Test (TCT), and Postural Assessment Scale for Stroke-trunk control (PASS-TC) were used for examining the trunk control. Spearman's correlation was used to analyze the relationship between TUG, SBS, TIS, TCT, and PASS-TC. RESULTS: The TUG is significantly correlated with SBS (r = -0.78), TIS (r = -0.76), TCT (r = -0.65), and PASS-TC (r = -0.67). In addition, the receiver operation characteristic (ROC) curve showed as cut-off value of SBS as >28.5, TIS > 16.5, TCT >82, and PASS-TC >10.5. The area under the ROC curve in each of the four tests is moderately accurate for predicting the mobility of sub-acute stroke survivors (0.84 ~0.90) (0.7 < AUC ≤ 9 (moderate informative)). IMPLICATIONS: The SBS showed the highest correlation for mobility using TUG in the hemiplegic stroke survivors. Also, SBS was revealed as the most dominant examination tool predicting the mobility by TUG, it can be explained the sitting postural balance is the variable predicting the mobility in survivors of sub-acute stroke.

Development of an 360-degree virtual reality video-based immersive cycle training system for physical enhancement in older adults: a feasibility study : Development of immersive virtual cycle for older adults.

BACKGROUND: Recently, there is an increased number of studies that use 360° virtual reality (VR) video for medical and rehabilitative purposes. However, the 360° VR video experience for older adults has not yet been investigated. This study aimed to examine the validity of an 360° VR video-based immersive cycling training system (360° VRCTS) for older adults and to provide preliminary evidence of efficacy. METHODS: We developed a new virtual reality training system using an immersive environment 360° VRCTS. Five healthy older adults (2 males and 3 females) participated in this study. The system was tested in a single training session (biking for 20 min while viewing a 360° VR video scene through a large curved screen) to identify its strengths and weakness. The usability and acceptability of our system were measured using the system usability scale (SUS) and the simulator sickness questionnaire (SSQ). RESULTS: All participants successfully completed the session without any discomfort. The average score for the SUS was 94.60 (range, 90-100), indicating high usability of the technology. The average score for the SSQ was 2.24 (standard deviation = 2.05), indicating that the system is well tolerated and has few side effects. CONCLUSIONS: The 360° VRCTS may be a useful indoor training system for older adults due to its easy manipulation, high usability, and limited cybersickness. TRIAL REGISTRATION NUMBER: Clinical Research Information Services (CRiS), KCT0003555 , Registered February 25, 2019, https://cris.nih.go.kr/cris/index/index.do .

Pilates exercise focused on ankle movements for improving gait ability in older women.

Pilates exercise is a structured physical activity that has been demonstrated to improve physical functions in older adults. The aim of this study was to determine whether Pilates exercise can improve gait, muscle strength, and mobility in community-dwelling older women. Twenty-two participants were recruited (mean 75.68 years old) to perform Pilates exercise for 30 minutes, twice a week for 10 weeks. After 10 weeks, significant improvements were observed in the spatial gait parameters, muscle strength, and range of motion of ankle (P < .05). Pilates exercise is beneficial exercise to improve gait, muscle strength, and mobility in community-dwelling older women.

Partitioned gradient-index phononic crystals for full phase control.

Gradient-index phononic crystals (GRIN-PC), characterized by layers with spatially changing refractive indices, have recently been investigated as part of the effort to realize flat lenses in acoustic and elastic regimes. Such gradient-index lens must be inversely designed from the corresponding refractive indices in order to manipulate the target wave. Unfortunately, estimating the index of this type of lens is not straightforward and requires substantial iterative computation in general, which greatly limits the applicability of GRIN-PC to flat lenses. In this work, we propose a novel design of a GRIN-PC in which neighboring layers are separated by partitions, thus preventing waves in each layer from interacting with other layers. This partitioned GRIN-PC design enables us readily to control the phase gradient accurately at the lens' end, resulting in direct calculation of indices for target wave manipulation. A detailed methodology for partitioned GRIN-PC based collimator and Bessel-beam generator is proposed and experimentally validated to confirm the versatile use of our design in wave engineering applications.

The Vacuum Assisted Negative Pressure Isolation Hood (VANISH) System: Novel Application of the Stryker Neptune™ Suction Machine to Create COVID-19 Negative Pressure Isolation Environments.

Coronavirus disease 2019 (COVID-19) may remain viable in the air for up to three hours, placing health care workers in close proximity to aerosolizing procedures particularly at high risk for infection. This combined with the drastic shortage of negative pressure rooms hospitals worldwide has led to the rapid innovation of novel biohazard isolation hoods, which can be adapted to create negative pressure isolation environments around the patient's airway using the hospital wall suction, which carries many limitations, including weaker suction capabilities, single patient use, and immobility. Here, we report our Vacuum Assisted Negative Pressure Isolation Hood (VANISH) system that uses a mobile and readily available in most hospital operating rooms Stryker Neptune™ (Stryker Corporation, Kalamazoo, Michigan) high-powered suction system to more effectively create a negative pressure biohazard isolation environment. VANISH has been utilized regularly in an anesthesia practice of 30+ providers and, to date, there have been no documented COVID-19 infections.