Wear Comfort Research Articles

Functional performance of low-cost electronic yarn for E-textiles

The current work presents and discusses the design and performance qualities of braided electronic yarns for woven textiles to produce red light-intensity effects. The design process involves a simple encapsulation process with adhesive tape and a heat-shrinkable tube to secure stainless-steel conductive threads (SS-CTs) to the solder pads of light-emitting diodes. These are arranged in a series against two SS-CTs to provide single positive and negative terminals at both ends. Findings from the infrared images show that the heat distribution and dissipation of the stainless-steel conductive threads are insignificant in affecting the wear comfort of the electronic textiles on the human body. The washing test shows the robust nature of the braided electronic yarns even after 20 cycles of being subjected to high agitation and mechanical stress. A proof of concept illustrates the effectiveness of the study results, which calls on further research work to enhance the durability and flexibility of the braided electronic yarns and electronic textiles to ensure a higher level of wear comfort. These braided electronic yarns would find end applications for nighttime visibility of pedestrians, a situation that would improve the recognition of drivers for reduced collision.Graphical abstractA simple low-cost process to manufacture electronic yarns (e-yarns) starts by embedding light-emitting diodes (LEDs) in series on two stainless-steel conductive threads (SS-CTs) through encapsulation in a heat-shrinkable tube (HST), and insulating one side of the SS-CT, then braided by using 8-core retroreflective threads that are then woven to form an electronic textile (e-textile). The braided e-yarns and e-textiles when washed exhibit good performance properties for clothing that would be interactive to enhance the nighttime visibility of pedestrians.Impact statementElectronic textiles otherwise known as e-textiles have been the subject of scholarly attention in recent years due to their performance properties and wide areas of application for entertainment, monitoring, and safety purposes. The use of appropriate electronic yarns (e-yarns) plays a key role in connectivity and provides the necessary feedback when applied to a textile material. E-yarns are now replacing a few modern electronic textiles (e-textiles) that use rigid copper wires commonly applied in electronic circuits for e-textiles and improve the wear comfort of the garment. The integration of light-emitting diodes (LEDs) into conductive threads to form electronic yarns for textile material can be applied not only for entertainment purposes but also as a safety feature for pedestrians. The use of appropriate components is necessary to ensure and maintain the textile quality and properties for effective wearability. Herein, an e-yarn fabricated with stainless-steel conductive threads and LEDs for e-textiles is presented. As part of ongoing research work to develop smart interactive clothing to increase the nighttime visibility of pedestrians, this work discusses the design and performance qualities of braided e-yarns for woven textiles. The success of these low-cost, flexible, and strong (high wash durability) braided e-yarns facilitates their integration into woven fabrics for smart clothing to enhance the visibility and therefore safety of pedestrians.

Sandwich-structured bimodal fiber/bead-on-string fiber composite membrane for comfortable PM0.3 filter

Particulate matter (PM) pollution causes critical harm to human health and global environment. However, the protective respirators attain high-performance filtration of the most permeable PM0.3 by tight stacking of fibers and seriously compromising their wearing comfort. Herein, a fluffy sandwich-structured membrane (SSM) composed of bimodal fibrous layers and bead-on-string fibrous layer is designed to endow the air filter with both high-performance filtration and superior thermal-wet comfort. Based on the electrospinning technique, the bimodal fibers made of nano-/submicron-fibers (about 46 nm and 155 nm) are formed by inducing the jet splitting while the bead-on-string fibers consisting of submicron-fibers (≈ 120 nm) and micro-beads (≈ 3.37 μm) are prepared through manipulating the Rayleigh instability of jets. Due to the structural design of small pores and low packing density, the SSM exhibits excellent PM0.3 removal of 99.8%, low filtration resistance of 65 Pa, and high quality factor of 0.097 Pa-1. It also shows long-term filtration stability and durability under high humidity conditions. Moreover, the SSM simultaneously possesses superior thermal-wet comfort of heat dissipation, air permeability of 164 mm·s-1, and water vapor transmission of 7.6 kg·m-2·d-1. This work may offer a novel insight for exploiting high-performance and comfortable personal protective materials.

Improvement of the technology of manufacturing clothes of law enforcement agencies

Special requirements are imposed on the uniform of a serviceman due to the specific use in different conditions. Special attention is paid to the comfort of wearing, the quality of materials and construction of clothing, hygienic and tactical and technical properties. When designing thermal protective clothing, it must be borne in mind that its thermal resistance must ultimately be assessed by the cumulative insulating effect of the finished structure. This scientific article attempts an in-depth analysis of the study of the problem of choosing the best range of materials necessary for the manufacture of uniforms intended for use in law enforcement agencies. The purpose of this study is to carefully determine the optimal combination of materials that is guaranteed to ensure a high standard of quality, durability and functionality of the uniform, as well as compliance with its requirements for modern service conditions. The article analyzes various aspects that affect the choice of materials, including their strength, comfort, protective properties and aesthetic aspect. The obtained research results, in turn, are aimed at improving the process of developing and manufacturing uniforms for law enforcement agencies, which, ultimately, will lead to an increase in the level of comfort and safety for its future wearers.

Microplastic-free, single-layered functional surface with localized liquid-discharging molecular channels for disposable hygiene products

Conventional disposable absorbent hygiene products (DAHPs) currently represent a significant type of solid waste in landfills and are a substantial producer of fiber-based microplastics. In this work, a novel multifunctional cellulose nonwoven (CNW) is reported. The key structural design of this material was achieved by covalently grafting a naturally cycloheptatriene product namely hinokitiol and a silane covalent bridge, successfully transforming the original super hydrophilic substrate into a single-layered, multifunctional material with precisely designed liquid-discharging molecular channels and a tailored, sophisticated hydrophobic/hydrophilic distribution structure. This 3D structure perfectly mimics the conventional adhesive-bonded polyolefin/polyesters laminates comprising a top sheet and a liquid acquisition and distribution layer (ADL). The results of XPS and 1H NMR indicated the hinokitiol was successfully chemically bonded to the CNW surface. Compared with polyolefin or cotton substrates, the optimal CNW product (CNW-H-A-2) exhibits significantly improved long-term wearing comfort by minimizing the liquid strike-through time (by 26–27%), reducing wet-back amount (by 65–90%), and ensuring an outstanding air-permeability (3011 mm·s-1). Excellent antibacterial properties against Staphylococcus aureus (86.4%) and Escherichia coli (97.3%) were achieved due to the good preservation of the bioactive phenol groups of hinokitiol. Additionally, it can be completely enzymatically-degraded within 24 h. This strategy holds promise as a potential solution for mitigating fiber-based microplastics pollution of DAHPs.

Active Power Assist with Equivalent Force on Connection for Lower Limb Exoskeleton Robots

Active power-assist lower limb exoskeleton robots aim to enhance wearer assistance while ensuring wearer comfort and simplifying the exoskeleton’s design and control. This study proposes an active assistance method known as Equivalent Force on Connection (EFOC). The EFOC method effectively addresses the limitations encountered in conventional Joint Torque Proportional Compensation (JTPC) approaches. These limitations include the necessity for exoskeleton robot configurations to align with human limb structures for parallel assistance at each lower limb joint, as well as the exoskeleton’s inability to contribute a greater proportion of assistance due to the excessive load on specific skeletal and muscular structures, resulting in wearer discomfort. Furthermore, the effectiveness of the EFOC method is evaluated and validated for assistance during both the stance and swing phases of single-leg movements. Finally, the proposed EFOC method is implemented on a hydraulic-driven lower limb exoskeleton robot to assist wearers in squatting, stepping, and jumping locomotion. The experimental results demonstrate that the proposed EFOC method can effectively achieve the desired assistance effect.

A Comprehensive Review of Microbial Biofilms on Contact Lenses: Challenges and Solutions.

Contact lenses (CL) have become an immensely popular means of vision correction, offering comfort to millions worldwide. However, the persistent issue of biofilm formation on lenses raises significant problems, leading to various ocular complications and discomfort. The aim of this review is to develop safer and more effective strategies for preventing and managing microbial biofilms on CL, improving the eye health and comfort of wearers. Taking these into consideration, the present study investigates the intricate mechanisms of biofilm formation, by exploring the interplay between microbial adhesion, the production of extracellular polymeric substances, and the properties of the lens material itself. Moreover, it emphasizes the diverse range of microorganisms involved, encompassing bacteria, fungi, and other opportunistic pathogens, elucidating their implications within lenses and other medical device-related infections and inflammatory responses. Going beyond the challenges posed by biofilms on CL, this work explores the advancements in biofilm detection techniques and their clinical relevance. It discusses diagnostic tools like confocal microscopy, genetic assays, and emerging technologies, assessing their capacity to identify and quantify biofilm-related infections. Finally, the paper delves into contemporary strategies and innovative approaches for managing and preventing biofilms development on CL. In Conclusion, this review provides insights for eye care practitioners, lens manufacturers, and microbiology researchers. It highlights the intricate interactions between biofilms and CL, serving as a foundation for the development of effective preventive measures and innovative solutions to enhance CL safety, comfort, and overall ocular health. Research into microbial biofilms on CL is continuously evolving, with several future directions being explored to address challenges and improve eye health outcomes as far as CL wearers are concerned.

Reducing Leak and Increasing Comfort of an N95 Filtering Facepiece Respirator for Aged-Care Workers Using a Customized, Soft, and Compliant Mask Frame

Abstract This prospective cohort study examines the quantitative fit-factor and tolerability impact of a novel custom frame designed to fit beneath N95 filtering facepiece respirators (FFRs) in a healthcare setting. Conducted at a medium-sized metropolitan residential aged care facility (RACF) in South Australia, sixty participants underwent quantitative fit testing while wearing institutional-provided N95 FFRs. Utilizing three-dimensional (3D) face scanning with a proprietary iPhone app, personalized frames were created using flexible silicone foam with a rigid plastic interior “backbone” to ensure compliance and comfort. Following the fitting of custom frames, participants underwent repeat quantitative fit testing using the same style and size of N95 FFRs. Results indicate a remarkable improvement, with 81.5% of participants achieving a pass on quantitative fit testing when using their custom frame in conjunction with the N95 FFRs, compared to a baseline pass rate of only 21.7% (odds ratio (OR) 20.9, 95% confidence interval (CI): 8.26, 58.50, p < 0.001 via logistic regression). Additionally, participants reported a 2.4 times higher level of tolerability when wearing the custom frame with their N95 FFRs compared to using FFRs alone (p < 0.001). In conclusion, the study demonstrates that wearing a customized frame device under an N95 FFR significantly enhances the likelihood of achieving a pass on quantitative fitting and offers a substantially more tolerable experience for wearers. These findings highlight the potential of personalized frame devices to improve respiratory protection efficacy and wearer comfort in healthcare settings.

Design and analysis of a lower limb assistive exoskeleton robot.

In recent years, exoskeleton robot technology has developed rapidly. Exoskeleton robots that can be worn on a human body and provide additional strength, speed or other abilities. Exoskeleton robots have a wide range of applications, such as medical rehabilitation, logistics and disaster relief and other fields. The study goal is to propose a lower limb assistive exoskeleton robot to provide extra power for wearers. The mechanical structure of the exoskeleton robot was designed by using bionics principle to imitate human body shape, so as to satisfy the coordination of man-machine movement and the comfort of wearing. Then a gait prediction method based on neural network was designed. In addition, a control strategy according to iterative learning control was designed. The experiment results showed that the proposed exoskeleton robot can produce effective assistance and reduce the wearer's muscle force output. A lower limb assistive exoskeleton robot was introduced in this paper. The kinematics model and dynamic model of the exoskeleton robot were established. Tracking effects of joint angle displacement and velocity were analyzed to verify feasibility of the control strategy. The learning error of joint angle can be improved with increase of the number of iterations. The error of trajectory tracking is acceptable.

Bioinspired composite fiber aerogel pressure sensor for machine-learning-assisted human activity and gesture recognition

Machine-learning-assisted human activity and gesture recognition are valuable for human-computer interaction, and data acquisition often necessitates high-performance sensors. Here, inspired by spider web and bat wing airflow sensing system, polyimide fiber (PIF)/carbon black (CB) composite fiber aerogel (CFA) pressure sensor with biomimetic hair-Merkel cell sensitive unit was developed, exhibiting ultralow detection limit (2 Pa), high pressure sensitivity (S=23.1 kPa-1), wide linear detection capacity up to 67.61 kPa, and fast response/recovery time (140/100 ms). Thanks to the excellent mechanical property and environmental tolerance of CFA, it also possesses excellent low fatigue over >4000 cycles and good durability even at extreme high-temperature (200 °C) and underwater conditions. The superior signal data of the sensor, combined with the Convolutional Neural Network machine learning algorithm, achieves ultra-high prediction accuracies of 96.73% and 98.26% for human activity and gesture recognition, respectively. Additionally, CFA also has amazing thermal management properties, making it to be an ideal candidate for wearable electronics with excellent wearing comfort and safety.

Fabrication of Microgel-Modified Hydrogel Flexible Strain Sensors Using Electrohydrodynamic Direct Printing Method.

Hydrogel flexible strain sensors, renowned for their high stretchability, flexibility, and wearable comfort, have been employed in various applications in the field of human motion monitoring. However, the predominant method for fabricating hydrogels is the template method, which is particularly inefficient and costly for hydrogels with complex structural requirements, thereby limiting the development of flexible hydrogel electronic devices. Herein, we propose a novel method that involves using microgels to modify a hydrogel solution, printing the hydrogel ink using an electrohydrodynamic printing device, and subsequently forming the hydrogel under UV illumination. The resulting hydrogel exhibited a high tensile ratio (639.73%), high tensile strength (0.4243 MPa), and an ionic conductivity of 0.2256 S/m, along with excellent electrochemical properties. Moreover, its high linearity and sensitivity enabled the monitoring of a wide range of subtle changes in human movement. This novel approach offers a promising pathway for the development of high-performance, complexly structured hydrogel flexible sensors.

Tunable porous fiber-shaped strain sensor with synergistic conductive network for human motion recognition and tactile sensing

With the rapid development of portable electronic products, smart wearable devices show great application potential in personalized motion monitoring, health monitoring and even in human-machine interaction. In particular, high-performance flexible fiber-shaped strain sensors are receiving more and more attention because they can be well integrated with clothes or human skin for real-time human activities monitoring. However, achieving improved sensitivity, wide detection range, diverse applications and easy operation of them remains a challenge. Here, we adopt a simple wet-spinning technique to prepare a porous fiber-shaped carbon nanotubes (CNTs)/silver nanoparticles (AgNPs)/thermoplastic polyurethane (TPU) fiber (CATF) for high-performance strain sensor, of which the synergistic conductive network of CNTs and AgNPs enables a wide detection range (∼248 %), high sensitivity (GF > 4295), fast response/recovery time (120 ms/140 ms) and excellent stability. Interestingly, strain sensing range and sensitivity of the sensor can be tuned by changing the AgNPs loading to make it suitable for different application scenarios. All the merits of the sensor make it capable for diverse human movements monitoring, pronunciation recognition, and gesture recognition. More importantly, our prepared CATF strain sensor can be easily weaved into wearable smart textiles, showing great potential for tactile sensing to realize multi-touch and pressure tracking. Finally, the CATF also displays efficient photothermal conversion capability even under different tensile strains up to 150 %, showing great potential in human body thermal management to improve the wearing comfort of wearable electronic fabric.

Janus outdoor protective clothing with unidirectional moisture transfer, antibacterial, and mosquito repellent properties

Personal protective clothing with versatile and durable features is highly desirable for daily and specific environmental scenarios. Especially for outdoor workers or sports enthusiasts, prolonged outdoor exposure requires their clothing to be more functional to cope with a wide range of situations, such as heat stress in summer, odor generation after sweating, and mosquito bites. These not only reduce the wearing comfort of clothing, but also bring potential heat stroke, skin infections and diseases brought by mosquitoes. Currently, most outdoor protective clothes focus on a single function, such as waterproofing and UV protection and are not able to cope with the demand of multiple protections. In this paper, we developed permethrin-containing triblock cationic polymers (PTCPs) that can multi-functionalize outdoor clothing. Benefiting from their high affinity to polyester fibers, PTCP modified polyester yarns were obtained by an aqueous based finishing process. After that, a scalable machine-knitting fabrication technique is employed to fabricate Janus outdoor protective clothes (Janus-OPC). The as-prepared Janus-OPC exhibited excellent one-way moisture transfer properties (forward cumulative one-way transfer index (OWTI) of 924.23%, and backward OWTI of −690.52%), antimicrobial properties (97.73% and 99.72% against E. coli and S. aureus, respectively), and mosquito repellent properties (repelling rate of 76.19%). Moreover, the protective performance of the Janus-OPC was maintained after 50 times of equivalent home laundering cycles. This multifunctional protective clothing opens up a new direction for the next-generation outdoor wear.

Real-time monitoring of bacterial inactivating process of tailored bactericidal and antifouling cotton fabric with preserving its physicochemical properties and biocompatibility

Microorganisms present on cotton fabric (CF) significantly affect its wearing comfort and pose potential threats to human health. This is mainly attributed to the porous and hygroscopic nature of CF, which easily adsorbs proteins, oily substances, and mineral salts, creating a favorable environment for microorganism proliferations. The bacteria firmly adhered to CF are difficult to remove by conventional washing, resulting in persistent stains. Furthermore, the mechanisms underlying bacterial interaction with fibers and bacterial inactivation remain to be fully understood. Herein, we synthetized reactive Gemini quaternary ammonium salt (CGQ) and sulfopropylbetaine (CGB) to covalently bind onto CF, thereby engineering a customized antimicrobial and antifouling CF while preserving its physicochemical properties. Real-time monitoring of the bacterial inactivation process was also performed. The antimicrobial efficacy of CF finished with CGQ and CGQ/CGB, employing only 5.0 mg/mL antimicrobial concentration, surpassed 95 % against Escherichia coli and 99 % against Staphylococcus aureus after 50 washes. The loosely adhered bacteria on CGQ/CGB-finished CF can be easily eliminated through conventional washing, resulting in an enduring antimicrobial and antifouling surface. Consequently, we have developed a straightforward strategy for the large-scale production of superior antimicrobial and antifouling CF, presenting a versatile solution with wide applications. Additionally, this method offers an efficient strategy for real-time monitoring of the microorganism inactivation process.

Intensely bonded high filling bismuth oxide with chloroprene rubber to achieve lead-free flexible materials for γ-rays shielding

Achieving lead-free flexible materials with excellent γ-ray shielding as well as good mechanical properties are of significance to radiation protection safety and wear comfort of wearable articles. In this paper, polydopamine (PDA) is coated on Bi2O3 particles to form a typical core–shell structure Bi2O3@PDA, which is used to intensely bond bismuth oxide (Bi2O3) with chloroprene rubber (CR). It promotes the interface interaction between Bi2O3 and CR matrix, leading to the uniform dispersion of the filler and rich interfacial compatibility in CR/Bi2O3@PDA composite with as high as 50 wt% filling. Furthermore, 50 wt% CR/Bi2O3@PDA composite displays 53.6% shielding rate for 105 keV γ-rays. Meanwhile, its tensile strength and elongation at break are 9.6 MPa and 1424.8%, respectively, which are without sacrificing too much in comparison with the neat rubber. We propose a versatile route to prepare superior integrated properties of flexible materials, which can be used as wearable articles for radiation shielding.

Stretchable and Breathable Electroluminescent Displays Based on Ultrathin Nanocomposite Designs.

Stretchable electroluminescent devices represent an emerging optoelectronic technology for future wearables. However, their typical construction on sub-millimeter-thick elastomers has limited moisture permeability, leading to discomfort during long-term skin attachment. Although breathable textile displays may partially address this issue, they often have distinct visual appearances with discrete emissions from fibers or fiber junctions. This study introduces a convenient procedure to create stretchable, permeable displays with continuous luminous patterns. The design utilizes ultrathin nanocomposite devices embedded in a porous elastomeric microfoam to achieve high moisture permeability. These displays also exhibit excellent deformability, low-voltage operation, and excellent durability. Additionally, the device is decorated with fluorinated silica nanoparticles to achieve self-cleaning and washable capabilities. The practical implementation of these nanocomposite devices is demonstrated by creating an epidermal counter display that allows intimate integration with the human body. These developments provide an effective design of stretchable and breathable displays for comfortable wearing.

Breath moisture-induced electroactive nanofibrous membrane for efficient antibacterial and antiviral air filtration

The high humidity environment created by human breath can easily lead to charge loss in the mask's filter and weaken the mask's filtration effect on aerosols containing bacteria and viruses. Therefore, in this study, a breath moisture-induced electroactive nanofibrous membrane was prepared by incorporating Cu/Zn nanoparticles into cellulose acetate/poly (vinyl butyral) fibers. Adjacent Cu/Zn nanoparticles can form galvanic couples that can be activated by human breath to undergo redox discharge reactions, thus imparting moisture-induced electroactivity to nanofibrous membrane. Based on the moisture-induced electroactivity, nanofibrous membrane demonstrated antibacterial rates of 98.32 % against Escherichia coli (E. coli) and 99.06 % against Staphylococcus aureus (S. aureus). Moreover, moisture-induced electroactive nanofibrous membrane significantly reduced the titer of Enterovirus 71 (EV71) transmitted through the respiratory tract within 5 min. The excellent antibacterial and antiviral performance of electroactive nanofibrous membrane can be attributed to the synergistic effect of Cu/Zn’s electrical stimulation (ES) interference on the electrodynamics of bacteria and viruses, the generated reactive oxygen species (ROS), and the released metal ions. Benefiting from the increased surface potential from Cu/Zn galvanic couples, moisture-induced electroactive nanofibrous membrane exhibited a filtration efficiency of 99.61 % for PM0.3 particles while maintaining a low-pressure drop (78 Pa). Meanwhile, electroactive nanofibrous membrane showed excellent wear comfort and non-cytotoxicity. In summary, this moisture-induced electroactive nanofibrous membrane maintains high filtration performance and exhibits excellent antibacterial and antiviral activities, shedding some light on developing novel efficient air filters.

Self-Lubricating, Living Contact Lenses.

The increasing prevalence of dry eye syndrome in aging and digital societies compromises long-term contact lens (CL) wear and forces users to regular eye drop instillation to alleviate discomfort. Here a novel approach with the potential to improve and extend the lubrication properties of CLs is presented. This is achieved by embedding lubricant-secreting biofactories within the CL material. The self-replenishable reservoirs autonomously produce and release hyaluronic acid (HA), a natural lubrication and wetting agent, long term. The hydrogel matrix regulates the growth of the biofactories and the HA production, and allows the diffusion of nutrients and HA for at least 3 weeks. The continuous release of HA sustainably reduces the friction coefficient of the CL surface. A self-lubricating CL prototype is presented, where the functional biofactories are contained in a functional ring at the lens periphery, outside of the vision area. The device is cytocompatible and fulfils physicochemical requirements of commercial CLs. The fabrication process is compatible with current manufacturing processes of CLs for vision correction. It is envisioned that the durable-by-design approach in living CL could enable long-term wear comfort for CL users and minimize the need for lubricating eye drops.

Wearable Ring-Shaped Biomedical Device for Physiological Monitoring through Finger-Based Acquisition of Electrocardiographic, Photoplethysmographic, and Galvanic Skin Response Signals: Design and Preliminary Measurements.

Wearable health devices (WHDs) are rapidly gaining ground in the biomedical field due to their ability to monitor the individual physiological state in everyday life scenarios, while providing a comfortable wear experience. This study introduces a novel wearable biomedical device capable of synchronously acquiring electrocardiographic (ECG), photoplethysmographic (PPG), galvanic skin response (GSR) and motion signals. The device has been specifically designed to be worn on a finger, enabling the acquisition of all biosignals directly on the fingertips, offering the significant advantage of being very comfortable and easy to be employed by the users. The simultaneous acquisition of different biosignals allows the extraction of important physiological indices, such as heart rate (HR) and its variability (HRV), pulse arrival time (PAT), GSR level, blood oxygenation level (SpO2), and respiratory rate, as well as motion detection, enabling the assessment of physiological states, together with the detection of potential physical and mental stress conditions. Preliminary measurements have been conducted on healthy subjects using a measurement protocol consisting of resting states (i.e., SUPINE and SIT) alternated with physiological stress conditions (i.e., STAND and WALK). Statistical analyses have been carried out among the distributions of the physiological indices extracted in time, frequency, and information domains, evaluated under different physiological conditions. The results of our analyses demonstrate the capability of the device to detect changes between rest and stress conditions, thereby encouraging its use for assessing individuals' physiological state. Furthermore, the possibility of performing synchronous acquisitions of PPG and ECG signals has allowed us to compare HRV and pulse rate variability (PRV) indices, so as to corroborate the reliability of PRV analysis under stationary physical conditions. Finally, the study confirms the already known limitations of wearable devices during physical activities, suggesting the use of algorithms for motion artifact correction.

The influencing factors of hearing protection device usage among noise-exposed workers in Guangdong Province: a structural equation modeling-based survey.

There are numerous complex barriers and facilitators to continuously wearing hearing protection devices (HPDs) for noise-exposed workers. Therefore, the present study aimed to investigate the relationship between HPD wearing behavior and hearing protection knowledge and attitude, HPD wearing comfort, and work-related factors. A cross-sectional study was conducted with 524 noise-exposed workers in manufacturing enterprises in Guangdong Province, China. Data were collected on hearing protection knowledge and attitudes, HPD wearing comfort and behavior, and work-related factors through a questionnaire. Using structural equation modeling (SEM), we tested the association among the study variables. Among the total workers, 69.47% wore HPD continuously, and the attitudes of hearing protection (26.17 ± 2.958) and total HPD wearing comfort (60.13 ± 8.924) were satisfactory, while hearing protection knowledge (3.54 ± 1.552) was not enough. SEM revealed that hearing protection knowledge had direct effects on attitudes (β = 0.333, p < 0.01) and HPD wearing behavior (β = 0.239, p < 0.01), and the direct effect of total HPD wearing comfort on behavior was β = 0.157 (p < 0.01). The direct effect also existed between work shifts and behavior (β=-0.107, p < 0.05). Indirect relationships mainly existed between other work-related factors, hearing protection attitudes, and HPD wearing behavior through knowledge. Meanwhile, work operation had a direct and negative effect on attitudes (β=-0.146, p < 0.05), and it can also indirectly and positively affect attitudes through knowledge (β = 0.08, p < 0.05). The behavior of wearing HPD was influenced by hearing protection knowledge, comfort in wearing HPD, and work-related factors. The results showed that to improve the compliance of noise-exposed workers wearing HPD continuously when exposed to noise, the HPD wearing comfort and work-related factors must be taken into consideration. In addition, we evaluated HPD wearing comfort in physical and functional dimensions, and this study initially verified the availability of the questionnaire scale of HPD wearing comfort.

Fabrication of Flexible and Conductive Microneedle Array Electrodes from Silk Fibroin by Mesoscopic Engineering

AbstractConventional electrodes are of significant challenges in acquiring bioelectric signals concerning a high signal‐to‐noise ratio (SNR), long‐term and comfortable wear, low motional noise, etc. To resolve these issues, silk fibroin (SF) materials are adopted to create flexible microneedle array electrodes (FMNA‐electrode) based on meso‐engineering. The research approaches involve constructing flexible conductive electrodes from non‐conductive and bristle‐regenerated SF. By controlling the molecular interchain nucleation in the refolding process of unfolded regenerated SF molecules, this goal can be achieved. In this process, silver nanowires (Ag NWs) are adopted as meso‐dopants to reconstruct the meso‐electronic structure of SF films at the surface, while polyurethane (PU) is selected as molecular templates to facilitate the molecular nucleation in the refolding of SF molecules. This leads to the occurrence of SF‐PU meso‐hybridization, giving rise to more flexible meso‐hybridized SF. The SF‐PU FMNA‐electrode demonstrates biocompatibility, comfort wearing, long‐term monitoring capability, low motional noise, and a high SNR in the application of collecting ECG, EMG, and EOG signals. The outperformance of SF‐PU FMNA‐electrode is superior to both conventional wet and commercially available dry electrodes, paving the way for the next generation of flexible, skin‐friendly, durable, and high‐performance health monitoring devices and brain‐machine interfaces.