Knee Bending Research Articles

Flame-induced performance enhancement of MXene-based nanocomposite sponge for infrared stealth and strain sensing

Assembling MXene nanofillers on a macroscopic carrier via the non-covalent bonding forces is one of the most efficient paths for preparing the MXene-based nanocomposites with multi functions and hierarchical structure. However, the frequently-used substrates, such as cotton fabric, synthetic textile, and polymer sponge are highly flammable, severely restricting the practical applications in some highly integrated scenarios. Herein, we report a facile design strategy that enables us to readily achieve the flame retardant MXene-based nanocomposites for highly efficient infrared stealth and strain sensing even when used in high-temperature environments. In particular, a phosphorus-nitrogen rich compound (HPTCP) was intercalated into the laminates of Ti3C2Tx-MXene to construct a hybrid flame retardant that was coated on the skeletons of melamine sponge by repeated dip-coating procedures. As a result of the synergistic effect among multicomponent, the Ti3C2Tx-HPTCP coated sponge displays excellent structural stability in real fire. In this case, flame treatment was adopted to create micro-/nano-scale cracks in the coated sponge and skeletons, significantly enhancing the sensitivity (∼0.20 kPa−1) and shortening the response time (69 ms) to strain. The burned sponge sensor can be employed for monitoring various human motions, from tiny throat vibrations and facial expressions to large-scale finger and knee bending. Besides, the burned sample still maintains the superior infrared stealth performance with a wide stealth temperature range, a large reduction in radiation temperature of 154 °C for the object temperature of 300 °C, and long-term working stability at high temperatures. Given the simple fabrication process, multilevel structural design, and stable performance, this work provides a promising strategy for addressing the flammability issue of template-based composite materials

Tibial contact points cannot be used to determine internal-external axial rotation of the native tibiofemoral joint

BackgroundIn the study of tibiofemoral kinematics of the native knee, internal-external (IE) axial rotation is a motion of interest. Locations of contact by the femur on the tibia (termed tibial contact points) have been used to determine IE rotations but such rotations might not be useful due to large error. Hence, our objective was to determine whether tibial contact points are useful in quantifying IE rotations of the native knee. MethodFluoroscopic images of the native knee were analyzed from 25 subjects who performed a weight-bearing deep knee bend. For each subject, 3D bone + cartilage models were created. Following 3D model-to-2D image registration, anterior-posterior (AP) positions of the lowest points and the tibial contact points were computed for each femoral condyle at 0°, 30°, 60°, and 90° of flexion. IE rotations were the angles between lines connecting points in the medial and lateral tibial compartments at different flexion angles. ResultsBased on the lowest points, the tibia rotated internally on the femur primarily during the first 30° of flexion. In this range, mean internal tibial rotation based on tibial contact points was negligible but internal tibial rotation was significantly greater based on lowest points (0° vs 7°, p = 0.0002). At 90° of flexion, the difference was maintained (1.8° vs 8.3°, p = 0.0007). ConclusionWhile tibial contact points are useful in the study of wear of tibial inserts in total knee arthroplasty (TKA), tibial contact points considerably underestimate internal tibial rotation during flexion in the native knee and should not be used to quantify tibiofemoral kinematics.

Development of a Knee Orthosis to Prevent Falling Due to Buckling among Elderlies

The number of elderlies increases over the years and has triggered concerns on healthcare system, the community and the family. Elderly could experience knee buckle and fall due knee osteoarthritis (OA), a common syndrome of weakness due to aging degeneration. It may cause pain and injuries and hence fears to stay mobile. As a result, this would give a negative effect to mental and physical health. It is common that elderlies attempt to wear an assistive knee device in hope of providing security in walking. The aim of this project is to survey the faith of elderlies in knee braces, to investigate the stiffness of sampled market knee braces/orthoses again sudden knee buckling and to propose a novelty design of a mechatronic knee orthosis. From the survey, the elderlies are general having faith in wearing a knee brace / orthosis to provide walking security. Secondly, from the experimental load test, the findings revealed that these sampled knee brace or orthoses do not feature on delayed bending when knee buckling occurred. Finally, the proposed design has revealed improved knee stiffness and prolong delayed knee bending.

Impact of Surgical Alignment, Bone Properties, Anterior-Posterior Translation, and Implant Design Factors on Fixation in Cementless Unicompartmental Knee Arthroplasty.

Micromotion exceeding 150 μm at the implant-bone interface may prevent bone formation and limit fixation after cementless knee arthroplasty. Understanding the critical parameters impacting micromotion is required for optimal implant design and clinical performance. However, few studies have focused on unicompartmental knee arthroplasty (UKA). This study assessed the impacts of alignment, surgical, and design factors on implant-bone micromotions for a novel cementless UKA design during a series of simulated daily activities. Three finite element models that were validated for predicting micromotion of cementless total knee arthroplasty (TKA) were loaded with design-specific kinematics/loading to simulate gait (GT), deep knee bending (DKB), and stair descent (SD). The implant-bone micromotion and the porous surface area ideal for bone ingrowth were estimated and compared to quantify the impact of each factor. Overall, the peak tray-bone micromotions were consistently found at the lateral aspect of the tibial baseplate and were consistently higher than the femoral micromotions. The femoral micromotion was insensitive to almost all the factors studied, and the porous area favorable for bone ingrowth was no less than 93%. For a medial uni, implanting the tray 1 mm medially or the femoral component 1 mm laterally reduced the tibial micromotion by 19.3% and 26.3%, respectively. Differences in tray-bone micromotion due to bone moduli were up to 59.8%. A 5 mm more posterior femoral translation increased the tray-bone micromotion by 35.8%. The presence of the tray keel prevented the spread of the micromotion and increased the overall porous surface area, but also increased peak micromotion. The tray peg and the femoral anterior peg had little impact on the micromotion of their respective implants. In conclusion, centralizing the load transfer to minimize tibial tray applied moment and optimizing the fixation features to minimize micromotion are consistent themes for improving cementless fixation in UKA. Perturbation of femoral-bone alignment may be preferred as it would not create under/overhang on the tibia.

CPoser: An Optimization-after-Parsing Approach for Text-to-Pose Generation Using Large Language Models

Text-to-pose generation is challenging due to the complexity of natural language and human posture semantics. Utilizing large language models (LLMs) for text-to-pose generation is appealing due to their strong capabilities in text understanding and reasoning. However, as LLMs are designed for general-purpose language processing and not specifically trained for pose generation, it remains nontrivial to generate precise articulation targets for the full body using LLMs directly. To this end, we propose CPoser, a novel approach to harness the power of LLMs for text-to-pose generation, featuring a prompt parsing stage and a pose optimization stage. The parsing stage utilizes LLMs to turn text prompts into pose intermediate representations (Pose-IRs) through a set of predefined structured queries. These Pose-IRs explicitly describe specific pose conditions, such as squatting depth and knee bending angle, naturally forming an objective function that a target pose should satisfy. The optimization stage solves for expressive poses and hand gestures based on the Pose-IR objective function via robust optimization in a quantized pose prior space. The results are further refined to enhance naturalness and incorporate facial expressions. Experiments show that our approach effectively understands diverse text prompts for pose generation, surpassing existing text-to-pose methods.

A deep learning-based comprehensive robotic system for lower limb rehabilitation

In the modern era, a significant percentage of people around the world suffer from knee pain-related problems. ‘Knee pain’ can be alleviated by performing knee rehabilitation exercises in the correct posture on a regular basis. In our research, an attention mechanism-based CNN-TLSTM (Convolution Neural Network-tanh Long Sort-Term Memory) network has been proposed for assessing the knee pain level of a person. Here, electroencephalogram (EEG) signals of the frontal, parietal, and temporal lobes, electromyography (EMG) signals of the hamstring and quadriceps muscles, and knee bending angle have been used for knee pain detection. First, the CNN network has been utilized for automated feature extraction from the EEG, knee bending angle, and EMG data, and subsequently, the TLSTM network has been used as a classifier. The trained CNN-TLSTM model can classify the knee pain level of a person into five categories, namely no pain, low pain, medium pain, moderate pain, and high pain, with an overall accuracy of 95.88 %. In the hardware part, a prototype of an automated robotic knee rehabilitation system has been designed to help a person perform three rehabilitation exercises, i.e., sitting knee bending, straight leg rise, and active knee bending, according to his/her pain level, without the presence of any physiotherapist. The novelty of our research lies in (i) designing a novel deep learning-based classifier model for broadly classifying knee pain into five categories, (ii) introducing attention mechanism into the TLSTM network to boost its classification performance, and (iii) developing a user-friendly rehabilitation device for knee rehabilitation.

Consequence of Orange Theory Fitness Training on Selected Health Related Physical Fitness Variables among Obese

Abstract The main task of the study was to find out Consequence of orange theory fitness training on Selected Health Related Physical Fitness Variables among Obese. To achieve the task of the study Forty class-I obese school boys were selected from various schools in Tuticorin were selected as subjects and their age ranged from 12-15 years only. The selected subjects were divided into two equal groups namely experimental group (20) and control group (20). The experimental group participated in orange theory fitness training. Pre and post-test method were followed. The experimental training was adopted for eight weeks on three days a week and control group was not exposed to experimental treatment. The selected variables namely flexibility, cardio respiratory endurance and muscular endurance. The above selected variables were tested through Flexibility (sit and reach in centimetre), Cardio Vascular Endurance (1.6 mile run in five minutes), and Muscular Endurance (bent knee sit-ups). The collected data were statistically analyses using dependent 't' test. The level of confidence was fixed at 0.05 for all cases. The result of the study showed that there was a significant improvement in flexibility, cardio respiratory endurance and muscular endurance among class -I obese school boys due to orange theory fitness training.

High-Performance Flexible Pressure Sensor with Micropyramid Structure for Human Motion Signal Detection and Electromagnetic Interference Shielding.

Flexible pressure sensors have a wide range of applications in the field of human motion signal detection, but the electromagnetic radiation generated during the monitoring process has become an unavoidable problem. Nowadays, it is still a challenge to develop high-performance pressure sensors with excellent electromagnetic interference (EMI) shielding performance. Herein, the Ti3C2TX MXene/carbon fiber/multiwalled carbon nanotube/polydimethylsiloxane (MXene/CMP) films with a micropyramidal structure were developed by the technology of vacuum high-temperature hot pressing and spray deposition. Benefiting from the dielectric loss of the conductive fillers and the presence of the microstructure, the MXene/CMP film exhibits excellent EMI shielding performance, and the EMI shielding efficiency (SE) can reach 49.37 dB. Besides, the introduction of CF effectively improves the mechanical properties of the MXene/CMP films, and the MXene nanosheets deposited on the surface of the film can reduce stress concentration, which in turn delays the expansion of cracks. Furthermore, the MXene/CMP sensor exhibits high sensitivity (89.76 kPa-1) and fast response/recovery time (61/60 ms). The deformation of microstructure and the construction of conductive networks enable the sensor to realize the monitoring of human motion signals (such as finger bending, knee bending, wrist bending, etc.). Meanwhile, the sensor maintains sensing stability even after 2000 pressure cycles, which can be attributed to the improvement in mechanical properties. In summary, the developed high-performance flexible pressure sensor with micropyramid structure has great application prospects in wearable devices and healthcare.

Foot Posture and Ankle Dorsiflexion as Risk Factors for Developing Achilles Tendinopathy and Plantar Fasciitis: A Case-Control Study.

Plantar fasciitis (PF) and Achilles tendinopathy (AT) are common injuries that primarily affect people engaged in sport or occupational weightbearing activities. Identifying modifiable risk factors is important for the treatment and prevention of these injuries. The purpose of this study was to evaluate whether foot posture or ankle dorsiflexion are risk factors for developing AT or PF, and if there were any differences between PF and AT patients. This was a case-control study of 108 patients with PF and 114 patients with AT, compared to the same number of referred patients in 2 control groups never having had these injuries, matched for sex, age, body mass index (BMI), sport, and occupational weightbearing activities. Included patients were 20-65 years with ultrasonographic-verified PF or midsubstance AT. Foot posture was assessed using Foot Posture Index (FPI) classifying the feet into 3 categories: FPI 0-5 normal foot, 6-12 hyperpronated, <0 hypopronated. Ankle dorsiflexion was measured with a goniometer in weightbearing with straight and bent knee. Abnormal foot posture was associated with an increased risk for sustaining both AT (odds ratio [OR] 3.4-4.1) and PF (OR 3.2-3.8). Hyperpronation being the major reason for this association with ORs 5.4-5.5 compared with hypopronation with ORs 2.6-2.9. However, decreased dorsiflexion was not a risk factor: instead, there was an increased ankle dorsiflexion in patients with AT or PF compared with their control groups. Comparison between PF and AT patients demonstrated that PF affected mostly women, and AT mostly men, PF patients were 2.4 years (CI 0.2-4.5) younger, and had 25% more occupational weightbearing than AT patients. However, no differences in BMI or weightbearing physical activity was demonstrated. Hypopronation and hyperpronation but not limited ankle dorsiflexion was associated with increased risk for AT or PF.

The MnAl-alloy nanoparticles incorporated PVDF-based piezoelectric nanogenerator as a self-powered real-time pedometer sensor

This study introduces a flexible, sensitive, and cost-effective hybrid piezoelectric nanogenerator (PENG) by integrating MnAl-alloy nanoparticles into a poly (vinylidene fluoride) (PVDF) nanocomposite film. The MnAl-alloy nanoparticles serve as a nucleating agent for promoting the formation of the electroactive β-phase. It is observed that the electroactive β-phase, dielectric permittivity, saturation polarization, and output performance of the device improve with the incorporation of the MnAl-alloy nanoparticles up to 7.5 wt. % in the PVDF matrix. Hence, in this work, we report a MnAl-alloy-based optimized piezoelectric nanogenerator device using a free-standing nanofiber mat (7.5 wt. % MnAl-alloy) prepared by the electrospinning technique. The as-fabricated piezoelectric nanogenerator effectively channels charges generated by mechanical stress to the electrodes, resulting in an impressive output voltage of approximately 16 V and an output current of around 7.1 μA, yielding a power of 47 μW across 4.5 MΩ resistor. Furthermore, energy harvesting from human movements such as jogging, knee bending, and walking is demonstrated for practical application. A piezo potential of approximately 8 V generated during walking showcases the development of a self-powered pedometer. Furthermore, tapping the PENG charges a capacitor of 0.1 μF up to approximately 1 V, demonstrating the potential application for the power up of small portable electronic devices.

Nanograting-assisted flexible Triboelectric Nanogenerator for active human motion detection

This manuscript presents the development of a nanograting assisted Triboelectric Nanogenerator (TENG) for improved performance. The TENG leverages a cost-effective and straightforward fabrication method, utilizing nano-gratings on a Polydimethylsiloxane (PDMS) layer to enhance the triboelectric effect. The device characteristics are evaluated by considering tapping force, separation distance, and load resistance. The experimental electrical characterization shows that the output voltage increases significantly with higher applied forces, with a 2N force generating voltage increases of over 584% compared to a 0.1N force. Conversely, the output voltage decreases as the separation distance is reduced. The charge storage capability of the proposed device is demonstrated by integrating a TENG with a full-wave bridge rectifier. Furthermore, the fabricated TENG demonstrates remarkable sensitivity in detecting various body motions. When strategically placed on the biceps, the TENG effectively tracks muscle contraction and expansion with a voltage range of +0.5V to -1V, exhibiting a sensitivity of 1.5V per cycle. Similarly, the TENG accurately detects bending movements in the knee and elbow joints. For knee bending, the voltage output ranges from +2.5V to -1V, resulting in a sensitivity of 3.5V per cycle. Elbow flexion generates voltages between +4V and -5V, corresponding to a sensitivity of 9V per cycle. This clear correlation between voltage and specific body movements makes the TENG a promising candidate for wearable health and motion monitoring systems.

Does Cruciate Ligament Substitution and Implant Asymmetry Make a Difference for Total Knee Arthroplasty Kinematics? A Multi-Implant Evaluation

BackgroundThe non-implanted knee differs in comparison to total knee arthroplasty (TKA) designs, with regard to asymmetry and functionality of the anterior cruciate ligament and the posterior cruciate ligament. While surgeons may choose to implant either posterior stabilized (PS) or bi-cruciate stabilized (BCS) TKAs, substituting for one or both cruciate ligaments, the effects of symmetry versus asymmetry in substituting TKA designs have not been widely analyzed to determine possible benefits. Therefore, the objective of this research study was to determine if either TKA asymmetry and/or anterior ligament stabilization can lead to more normal-like kinematics and clinical benefit for patients. MethodsIn vivo, femoro-tibial kinematics for 64 subjects were evaluated in this retrospective study. Overall, 10 subjects had a normal, nonimplanted knee, 20 had a BCS TKA, and 34 had one of two different PS TKAs. All three TKAs had varying degrees of symmetry incorporated into the design, and all were implanted by the same surgeon and were analyzed using fluoroscopy during a deep knee bend. ResultsAt full extension, the BCS TKA subjects demonstrated a statistically more anterior position of both condyles compared to both PS TKAs. The BCS TKA subjects also experienced more posterior femoral rollback (PFR) and axial rotation in early flexion and from full extension to maximum knee flexion. Additionally, the TKAs in this study having asymmetry experienced greater amounts of PFR and weight-bearing knee flexion. ConclusionsThe results from this study indicated that in early flexion, the anterior cam/post mechanism does pull the femoral component more anterior, and all TKAs experienced PFR when the posterior cam engaged the post. The asymmetric designs also achieved greater rollback and axial rotation compared to the symmetric designs.

Development of prediction model for risks of musculoskeletal chronic lumbopelvic pain in Indian women

Chronic lumbopelvic pain (CLPP) and its associated disabilities significantly affect women's social, professional, and personal lives. However, the specific factors contributing to CLPP in women remain unclear. To address this gap, this prospective cross-sectional study aims to identify the risk factors predicting CLPP in women and develop a prediction model that can predict CLPP in women. The study was conducted across Delhi, India, where free health camps were held, and 2400 women were assessed. Among the assessed individuals, the study revealed a high prevalence rate of CLPP among Indian women, standing at 70.4%. Seven risk factors namely, hamstring muscle tightness (> 20° on passive knee extension test), increased lumbar lordosis (> 11.5 cm of the lumbar lordotic index), reduced hip flexibility (> 15 cm on bent knee fallout test), altered foot posture (≥ 20 on foot posture index score), increased perception of psychological stress (> 25 on cohen’s perceived stress scale-10 score), reduced physical activity level (< 475 metabolic/minute on international physical activity questionnaire) and reduced performance of transversus abdominis muscle (≤ 5 on deep muscle contraction scale score) strongly predict the risks of CLPP in women. Identifying these risk factors is crucial for effectively preventing and managing CLPP symptoms, especially considering its high prevalence among Indian women. Health professionals should prioritize raising awareness about CLPP and its causative factors, as well as implementing strategies for early detection and intervention.

The Association Between Femoral Nerve Tension and Hip Flexor Length

Background: Femoral nerve tension and hip flexor muscle length are critical factors in musculoskeletal health. Their relationship is particularly important in diagnosing and managing conditions like low back pain, often associated with tight hip flexors.Objective: This study aimed to explore the association between femoral nerve tension and hip flexor muscle length in individuals with acute low back pain compared to healthy controls.Methods: A correlational study was conducted with 68 participants (34 healthy controls and 34 acute low back pain patients). Data were collected using self-administered questionnaires and clinical tests, including the Prone Knee Bend Test and Modified Thomas Test. Femoral nerve tension and hip flexor length were measured using a goniometer. Data were analyzed using Pearson correlation and linear regression in SPSS version 25.Results: The Thomas Test showed a statistically significant negative correlation between femoral nerve tension and hip flexor length in Group B (-0.096, p=0.042). In the Prone Knee Bend Test, a minimal positive correlation was observed (0.007, p&gt;0.05). Cross-tabulation highlighted a significant association between test results in the control group (p=0.025).Conclusion: A significant relationship exists between femoral nerve tension and hip flexor length in individuals with acute low back pain. These findings suggest the need for targeted interventions focusing on neural and muscular components.

Early gait analysis after total knee arthroplasty based on artificial intelligence dynamic image recognition

To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty (TKA). From February 2023 to July 2023, 26 patients with unilateral knee osteoarthritis (KOA) were treated with TKA, including 4 males and 22 females, aged from 57 to 85 years old with an average of (67.58±6.49) years old;body mass index (BMI) ranged from 18.83 to 38.28 kg·m-2 with an average of (26.43±4.15) kg·m-2;14 patients on the left side, 12 patients on the right side;according to Kellgren-Lawrence(K-L) classification, 6 patients with grade Ⅲ and 20 patients with grade IV;the courses of disease ranged from 1 to 14 years with an average of (5.54±3.29) years. Images and videos of standing up and walking, walking side shot, squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation. The human posture estimation framework OpenPose were used to analyze stride frequency, step length, step length, step speed, active knee knee bending angle, stride length, double support phase time, as well as maximum hip flexion angle and maximum knee bending angle on squatting position. Western Ontario and McMaster Universities (WOMAC) arthritis index and Knee Society Score (KSS) were used to evaluate clinical efficacy of knee joint. All patients were followed up for 5 to 7 weeks with an average of (6.00±0.57) weeks. The total score of WOMAC decreased from (64.85±11.54) before operation to (45.81±7.91) at 6 weeks after operation (P<0.001). The total KSS was increased from (101.19±9.58) before operation to (125.50±10.32) at 6 weeks after operation (P<0.001). The gait speed, stride frequency and stride length of the affected side before operation were (0.32±0.10) m·s-1, (96.35±24.18) steps·min-1, (0.72±0.14) m, respectively;and increased to (0.48±0.11) m·s-1, (104.20±22.53) steps·min-1, (0.79±0.10) m at 6 weeks after operation (P<0.05). The lower limb support time and active knee bending angle decreased from (0.31±0.38) s and (125.21±11.64) ° before operation to (0.11±0.04) s and (120.01±13.35) ° at 6 weeks after operation (P<0.05). Eleven patients could able to complete squat before operation, 13 patients could able to complete at 6 weeks after operation, and 9 patients could able to complete both before operation and 6 weeks after operation. In 9 patients, the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation, and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation. Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of patients' gait. Knee pain of KOA was relieved and the function was improved, the supporting ability of the affected limb was improved after TKA, and the patient's stride frequency, stride length and stride speed were improved, and the overall movement rhythm of both lower limbs are more coordinated.

Gallic acid melanin pigment hydrogel as a flexible macromolecule for articular motion sensing

In this study, water-soluble melanin was synthesized through the genetic recombination of Escherichia coli using gallic acid as a substrate. The recombinant host produced 2.83 g/L of gallic acid-based melanin (GA melanin) from 20 mM gallic acid. Notably, the isolated GA melanin demonstrated exceptional antioxidant and antimicrobial activities, exhibiting a 25.7 % inhibition ratio against Candida albicans. The structure and composition of GA melanin were analyzed using Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and X-ray diffraction (XRD). Remarkably, GA melanin displayed high thermal stability, maintaining integrity up to 1000 °C. Additionally, it exhibited unique electrical properties in terms of conductivity and resistivity compared to other common types of melanin. Subsequently, GA melanin was cross-linked with hydrogel to create a sensing template. The resulting GA melanin hydrogel demonstrated lower resistance (80.08 ± 3.0 kohm) compared to conventional hydrogels (108.62 ± 10.4 kohm), indicating an approximately 1.77-fold improvement in adhesion. Given its physical, biological, and electrical properties, the GA melanin hydrogel was further utilized as a flexible motion-sensing material to detect resistivity changes induced by knee, wrist, and finger bending, as well as vocal cord vibrations. In all cases, the sensing module displayed notable sensitivity to motion-induced resistivity variations.

Association between Hip/Groin Pain and Hip ROM and Strength in Elite Female Soccer Players.

Background/Objectives: Hip strength and range of motion have been compared in soccer players with and without hip and groin pain but only in male footballers or gender-combined samples. In female soccer players, the biomechanics contributing to this injury remain poorly understood compared to other sporting injuries. The aim of the present study is to investigate whether differences exist in adductor and abductor isometric test values and hip joint range of motion between elite female soccer players with longstanding groin pain and injury-free controls. Methods: Ten female elite soccer players with current longstanding hip and groin pain and twenty-five injury-free controls from the same teams were included in the study. Hip adductor and abductor isometric strength were evaluated with a hand-held dynamometer. A bent knee fall-out test was also utilized to examine the hip joint range of motion. Results: A significant difference in abductor isometric test values was observed between the control group (2.29 ± 0.53 N/Kg) and the hip and groin pain group (2.77 ± 0.48 N/Kg; p = 0.018). Furthermore, the injured group showed a decreased adductor/abductor ratio compared to the control group (1.00 ± 0.33 vs. 1.27 ± 0.26; p = 0.013). No differences were observed in the bent knee fall-out test (p = 0.285). Conclusions: Female elite soccer players with current longstanding hip and groin pain exhibited higher abductor isometric strength and lower adductor/abductor ratio compared to non-injured women players. There were no differences in the BKFO test between groups.

Particle and bacterial colony emissions from garments and humans in pharmaceutical cleanrooms

Particles and bacteria released from operators in pharmaceutical cleanrooms significantly impact the quality of pharmaceutical products. Therefore, it is necessary to study particle and bacteria emissions from operators and their garments. This paper presents the results of experimental measurements of numbers of particles and bacterial emissions from integrated and split cleanroom garments, under different movement types and laundry conditions. The experiment demonstrated that the emission rate of 0.5 μm particles from split-type garments is approximately 2.0–3.5 times higher than that of integrated cleanroom garments, and 7.0–22.7 times for 5.0 μm particles. The particle emission rate of humans is closely related to the movement types, number of laundry cycles, and garment types. The maximum particle emission rates were obtained when wearing split cleanroom garment after 100 washes and performing knee bend, with 654603 P/min for 0.5 μm and 27185 P/min for 5.0 μm particles, respectively. The particle emission rate of humans is mainly caused by personnel movement, since the emission rate of garments accounts for at most 3.89 %. The bacteria colony of humans increases with the increase of laundry cycles of cleanroom garments. The maximum bacteria colony of integrated and split cleanroom garment were 4 CFU/plate and 9 CFU/plate with the laundry cycles of 100 times. The quantitative results of bacteria and particles emitted from pharmaceutical cleanroom operators are expected to ensure drug quality during production.

Highly conductive copper-coated polyamide yarn for wearable sensing and Joule heating applications

A highly conductive yarn was developed by electroless deposition of copper metal particles on the polyamide 6 yarn. The successful incorporation of Cu particles into the substrate was revealed by surface and elemental characterizations. The Cu/PA 6 yarn exhibited superior electrical conductivity (2.3 Ω/cm) with improved mechanical properties. The excellent electromechanical properties demonstrated by the Cu/PA 6 composite revealed its sensing capacity for a wide range of strains. Therefore, the composite yarn was affixed to the different regions of the human body and was capable of successfully monitoring various human motions, including finger bending, wrist bending, knee bending, drinking, and writing. In addition, rapid heat generation with high and uniform surface temperature (66.3 °C at 4.0 V in 45 s) validated the potential of the Cu/PA 6 yarn for wearable thermal heating devices. Moreover, rapid heating at a lower voltage, when attached to a wristband, revealed the capability of the composite yarn for localized heating or region-specific temperature regulation for personalized healthcare or comfort. This study informs a facile and effective strategy for developing robust yarn-shaped e-textiles for advanced wearable sensing and thermal heating.

Laser-Induced Graphene Strain Sensors for Body Movement Monitoring.

To enable the development of artificial intelligence of things, the improvement of the strain sensing mechanisms and optimization of the interconnections are needed. Direct laser writing to obtain laser-induced graphene (LIG) is being studied as a promising technique for producing wearable, lightweight, highly sensitive, and reliable strain sensors. These devices show a higher degree of flexibility and stretchability when transferred to an elastomeric substrate. In this article, we manufactured polydimethylsiloxane (PDMS)-encapsulated LIG piezoresistive strain sensors with a quasi-linear behavior and a gauge factor of 111. The produced LIG was morphologically characterized via Raman spectroscopy and scanning electron microscopy before and after the electromechanical characterization and before and after the LIG transfer to PDMS. The results from these analyses revealed that the integrity of the material after the test was not affected and that the LIG volume in contact with the substrate increased after transfer and encapsulation in PDMS, leading to the improvement of the sensor performance. The sensors' capability for measuring bend angles accurately was demonstrated experimentally, making them useable in a wide range of applications for human body movement monitoring as well as for structural health monitoring. Regarding body monitoring, a PDMS-encapsulated LIG sensor for knee bending angle detection was proposed. This device showed unaffected performance of 1500 cycles under 8% uniaxial deformation and with response times in the range of 1-2 s.