Wearing Experience Research Articles

Stretchable and High-Performance Fibrous Sensors Based on Ionic Capacitive Sensing for Wearable Healthcare Monitoring.

Electronic textiles with remarkable breathability, lightweight, and comfort hold great potential in wearable technologies and smart human-machine interfaces. Ionic capacitive sensors, leveraging the advantages of the electric double layer, offer higher sensitivity compared to traditional capacitive sensors. Current research on wearable ion-capacitive sensors has focused mainly on two-dimensional (2D) or three-dimensional (3D) device architectures, which show substantial challenges for direct integration with textiles and compromise their wearing experience on conformability and permeability. One-dimensional (1D) stretchable fiber materials serve as vital components in constructing electronic textiles, allowing for rich structural design, patterning, and device integration through mature textile techniques. Here, a stretchable functional fiber with robust mechanical and electrical performances is fabricated based on semi-solid metal and ionic polymer, which provided a high stretchability and good electrical conductivity, enabling seamless integration with textiles. Consequently, high-performance stretchable fiber sensors are developed through different device architecture designs, including pressure sensors with high sensitivity (7.21kPa-1), fast response (60ms/30ms), and excellent stability, as well as strain sensors with high sensitivity (GF = 1.05), wide detection range (0-300% strain), and excellent sensing stability under dynamic deformations.

Research progress on key technologies of flexible wearable electronic devices

Flexible wearable device is an innovative technology product, using soft, lightweight material design, can fit the curve of the human body, providing a comfortable wearing experience. These devices typically integrate a variety of sensors, batteries, and connectivity technologies to enable biometric monitoring, motion tracking, communication, and other intelligent functions. Traditional electronic products tend to give a "stiff" impression that they cannot withstand bending, twisting and stretching. In recent years, under the background of the integration of electronic technology and modern material science technology, the emerging flexible electronic wearable device has become a research hotspot with its more flexible material, more sensitive and accurate signal transmission, and more extensive monitoring range. The development of flexible electronic technology has greatly improved the user's wearing experience and is more suitable for the free movement of the human body. This paper summarizes the basic principle and classification of key technologies of wearable electronic devices, and introduces the research progress and research trend.

Bioinspired Flexible Kevlar/Hydrogel Composites with Antipuncture and Strain-Sensing Properties for Personal Protective Equipment.

Currently, multifunction has become an essential direction of personal protective equipment (PPE), but achieving the protective effect, flexibility, physiological comfort, and intelligent application of PPE simultaneously is still a challenge. Herein, inspired by the meso-structure of rhinoceros skin, a novel strategy is proposed by compounding an ammonium sulfate ((NH4)2SO4) solution soaked gelatin hydrogel with the high weight fraction and vertically interwoven Kevlar fibers to manufacture a flexible and wearable composite with enhanced puncture resistance and strain-sensing properties. After (NH4)2SO4 solution immersion, the hydrogel's tensile strength, toughness, and fracture strain were up to 3.77 MPa, 4.26 MJ/m3, and 305.19%, respectively, indicating superior mechanical properties. The Kevlar/hydrogel composites revealed excellent puncture resistance (quasi-static of 132.06 N and dynamic of 295.05 N), flexibility (138.13 mN/cm), and air and moisture permeability (17.83 mm/s and 2092.73 g m-2 day-1), demonstrating a favorable balance between the protective effect and wearing comfort even after 7 days of environmental exposure. Meanwhile, salt solution immersion endowed the composite with excellent strain-sensing properties at various bending angles (30-90°) and frequencies (0.25-1 Hz) and allowed it to monitor different human motions directly in real-time. The rhinoceros-skin-inspired Kevlar/hydrogel composites provide a simple and economical solution for antipuncture materials that combine high protective effects, a comfortable wearing experience, and good strain-sensing properties, promising multifunctional PPE in the future.

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.

Health Care Workers' Comfort Ratings for Elastomeric Half-Mask Respirators Versus N95® Filtering Facepiece Respirators During the COVID-19 Pandemic.

Reusable elastomeric half-mask respirators (EHMR) are an alternative to address shortages of disposable respirators. While respirator discomfort has been noted as a barrier to adherence to wearing an N95 filtering facepiece respirator (FFR) among health care personnel (HCP), few have examined EHMR comfort while providing patient care, which was the purpose of this study. Among a cohort of 183 HCP, we prospectively examined how HCP rated EHMR tolerability using the Respirator Comfort, Wearing Experience, and Function Instrument (R-COMFI) questionnaire at Study Week 2 and Week 10. At the completion of the study (Week-12), HCP compared EHMR comfort with their prior N95 FFR use. Overall R-COMFI scores and three subscales (comfort, wear experience, and function) were examined as well as individual item scores. The HCP reported an improved overall R-COMFI score (lower score more favorable, 30.0 vs. 28.7/47, respectively) from Week 2 to Week 10. Many individual item scores improved or remained low over this period, except difficulty communicating with patients and coworkers. The overall R-COMFI scores for the EHMR were more favorable than for the N95 FFR (33.7 vs. 37.4, respectively), with a large proportion of workers indicating their perception that EHMR fit better, provided better protection, and they preferred to wear it in pandemic conditions compared with the N95 FFR. Findings suggest that the EHMR is a feasible respiratory protection device with respect to tolerance. EHMRs can be considered as a possible alternative to the N95 FFR in the health care setting. Future work is needed in the EHMR design to improve communication.

A three-dimensional liquid diode for soft, integrated permeable electronics.

Wearable electronics with great breathability enable a comfortable wearing experience and facilitate continuous biosignal monitoring over extended periods1-3. However, current research on permeable electronics is predominantly at the stage of electrodeand substrate development, which is far behind practical applications with comprehensive integration with diverse electronic components (for example, circuitry, electronics, encapsulation)4-8. Achieving permeability and multifunctionality in a singular, integrated wearable electronic system remains a formidable challenge. Here we present a general strategy for integrated moisture-permeable wearable electronics based on three-dimensional liquid diode (3D LD) configurations. By constructing spatially heterogeneous wettability, the 3D LD unidirectionally self-pumps the sweat from the skin to the outlet at a maximum flow rate of 11.6 ml cm-2 min-1, 4,000 times greater than the physiological sweat rate during exercise, presenting exceptional skin-friendliness, user comfort and stable signal-reading behaviour even under sweating conditions. A detachable design incorporating a replaceable vapour/sweat-discharging substrate enables the reuse of soft circuitry/electronics, increasing its sustainability and cost-effectiveness. We demonstrated this fundamental technology in both advanced skin-integrated electronics and textile-integrated electronics, highlighting its potential for scalable, user-friendly wearable devices.

Machine learning-based prediction of tear osmolarity for contact lens practice.

This study addressed the utilisation of machine learning techniques to estimate tear osmolarity, a clinically significant yet challenging parameter to measure accurately. Elevated tear osmolarity has been observed in contact lens wearers and is associated with contact lens-induced dry eye, a common cause of discomfort leading to discontinuation of lens wear. The study explored machine learning, regression and classification techniques to predict tear osmolarity using routine clinical parameters. The data set consisted of 175 participants, primarily healthy subjects eligible for soft contact lens wear. Various clinical assessments were performed, including symptom assessment with the Ocular Surface Disease Index and 5-Item Dry Eye Questionnaire (DEQ-5), tear meniscus height (TMH), tear osmolarity, non-invasive keratometric tear film break-up time (NIKBUT), ocular redness, corneal and conjunctival fluorescein staining and Meibomian glands loss. The results revealed that simple linear regression was insufficient for accurate osmolarity prediction. Instead, more advanced regression models achieved a moderate level of predictive power, explaining approximately 32% of the osmolarity variability. Notably, key predictors for osmolarity included NIKBUT, TMH, ocular redness, Meibomian gland coverage and the DEQ-5 questionnaire. In classification tasks, distinguishing between low (<299 mOsmol/L), medium (300-307 mOsmol/L) and high osmolarity (>308 mOsmol/L) levels yielded an accuracy of approximately 80%. Key parameters for classification were similar to those in regression models, emphasising the importance of NIKBUT, TMH, ocular redness, Meibomian glands coverage and the DEQ-5 questionnaire. This study highlights the potential benefits of integrating machine learning into contact lens research and practice. It suggests the clinical utility of assessing Meibomian glands and NIKBUT in contact lens fitting and follow-up visits. Machine learning models can optimise contact lens prescriptions and aid in early detection of conditions like dry eye, ultimately enhancing ocular health and the contact lens wearing experience.

Energy Consumption during the Wearing of Pantyhose

The goal of the current study was to develop pantyhose that reduce leg muscle fatigue when heeled shoes are worn. To this end, pantyhose that provide a comfortable fitting sensation were developed, and the wear experience of the pantyhose and the effect of the pantyhose on energy consumption under walking muscle activity of the lower limbs were investigated. The study participants were 17 healthy Japanese females in their twenties who did not usually put on support wear. The respiratory metabolism was measured as the participants either walked without pantyhose or wore one of two types of pantyhose and wore three types of shoe, namely running/low-heeled/high-heeled shoes. Participants walked on a treadmill at 3 km/h. Regardless of whether pantyhose were worn, the energy consumption increased significantly with walking relative to standing. During walking, energy consumption increased significantly in the order of not wearing shoes, wearing running shoes, wearing low-heeled shoes, and wearing high-heeled shoes. In other words, a higher heel height corresponded to higher energy consumption, regardless of whether pantyhose were worn. Wearing pantyhose while standing upright increased energy consumption, especially in the case of pantyhose A, for which energy consumption was significantly higher than that when going barefoot. In addition, for walking in running shoes, the energy consumption was significantly higher when pantyhose A were worn than when no pantyhose were worn. The wearing of pantyhose A, but not the wearing of pantyhose B, was thus found to increase energy consumption.

Deepening the synergistic role of additive manufacturing and computational strategies in jewellery

This study investigates the synergy between additive manufacturing (AM) technologies and computational design strategies in jewellery and how that synergy can be successfully exploited to extend innovation in that field further. A case study called Ecdysis, a bioinspired jewellery collection, is presented. A dedicated computational algorithm has been developed and is described in detail. This algorithm allows for the exploitation of the shape and functional complexity dimensions allowed by AM and the control of the printability of the generated concept. Shape and functional complexity are exploited to mimic the beauty and dynamism of snakes’ slithering mechanism. At the same time, starting from the developed algorithm, multiple digital models and physical prototypes have been fabricated, leveraging material extrusion, vat photopolymerisation, and powder bed fusion processes. This further development step of the collection thus confirms the versatility of both the proposed approach and AM technologies for jewellery. Therefore, the paper demonstrates how unique wearing experiences can be created and how uniqueness can be simultaneously preserved and democratised in jewellery by deepening the synergy between AM technologies and computational strategies.

Wear Experience with a daily disposable soft contact lens for astigmatism in current wearers of a reusable soft toric contact lens.

The purpose of this study was to evaluate the wear experience of satisfied wearers of a particular reusable toric soft contact lens when refit into a water surface technology daily disposable toric soft contact lens. 30 participants completed the study over three visits. At the first visit, subjects were refit into with their habitual reusable toric soft contact lens (comfilcon A) to maximize fit and vision. Subjects returned after one week and were then refit into the study daily disposable soft contact lenses (verofilcon A) and completed surveys of their initial impressions of comfort, vision, and satisfaction. Participants wore the study lenses for two weeks, and then returned for their final visit to complete a vision and ocular health check. At the final visit, subjects also completed surveys to rate their overall and end-of-day comfort, quality of vision, stability of vision, and dryness using a visual analog scale (VAS). Participants also answered questions about their wear experience with the lenses. Overall median and interquartile range (IQR) of all data and surveys was calculated. Initial impressions of the study lenses revealed a median (IQR) score of 85 (28) for vision, 91 (25) for comfort, and 87 (21) for satisfaction. Overall VAS scores after two weeks of wear found median scores of 93 (16) for quality of vision, 88 (28) for stability of vision, and 91 (20) for comfort. End-of-day median scores were 82(27) for quality of vision, 90 (35) for stability of vision, and 80 (38) for comfort. Overall dryness scores were 20(45) and end-of-day dryness was 39 (46). Median(IQR) binocular logMAR visual acuity with the study lenses was -0.16(0.1). Median rotation of the lenses was 0(4.3) degrees. Participants wearing the daily disposable study lenses for astigmatism gave high scores in vision and comfort both at initial fitting and after two weeks of lens wear. Results showed that satisfied wearers of comfilcon A reusable toric soft contact lenses can be successfully refit with verofilcon A daily disposable contact lenses.

Design of Composite Parallel External Fixator for Multisegment Foot and Ankle Deformity Correction: A Correction Requirement- Dominated Approach

Foot and ankle deformity is a common complaint in orthopedic surgery, among which the multisegment concurrent types are even more severe. As a key medical device for multisegment deformity correction, the composite parallel external fixator (PEF) design has a profound impact on the correction outcomes. However, existing PEFs share a single configuration and have inadequate adaptation to various deformity types, leading to problems, such as complex structural composition, excessive adjustment parameters, and uncomfortable wearing experience. To overcome these problems, this article proposes a novel correction requirement-dominated design approach for composite PEF. Multisite frame mounting modes and multitype struts are introduced to form required PEF configurations. Lower mobility struts can constrain the unwanted degrees-of-freedom, thus enabling the device to precisely match the requirement-function relationship. Taking the double-segment deformity as research object, clinical cases, and composite PEF assembly simulations are provided. Experiments are carried out on the mechanical prototype. The mounting test proves the interconverting ability and deformity-targeting property of the derived composite PEFs. Moreover, the motion test verifies that the device can distract patients of different weights to complete the correction path, and the stability test demonstrates that the device can resist external bumps, thus indicating the feasibility of the approach.

EVALUATION OF WEAR EXPERIENCE WITH WATER SURFACE DAILY DISPOSABLE LENSES IN SATISFIED REUSABLE SOFT CONTACT LENS WEARERS.

Soft contact lens wearers are often prescribed the same lens material and modality for multiple years if patients express satisfaction and no significant problems with lens fit or ocular health are noted upon evaluation. Despite their satisfaction, it is possible that other lenses exist that could provide additional health or convenience benefits and still provide satisfied lens wear experience. In this study, wearers of a specific monthly replacement lens brand (comfilcon A) were recruited for an open-label study. The habitual contact lens prescription was optimized for 2 weeks of wear and participants confirmed that they were satisfied with their habitual lenses before being refit with daily disposable lenses (verofilcon A). Participants responded to visual analog scale (VAS) survey about their initial impressions of the lenses. After 2 weeks of lens wear, participants completed a final study visit and completed surveys about lens wear experiences with the daily disposable study lenses. Fifteen male and 15 female participants completed the study. Median (IQR) binocular LogMAR visual acuity was -0.20(0.12), which is equivalent to 10/12.5 Snellen acuity. Initial impression surveys revealed median (interquartile range) of 92.5(22.3) for quality of vision; 95.0(19.3) for comfort; and 91.5(19.3) for satisfaction. At the final visit, median scores for EOD quality of vision was 86.5(24.0); EOD comfort was 84.5(30.3), and EOD dryness 25.5(47.0). Median overall VAS scores were 92.5(16.0) for vision; 88.0(18.3) for comfort, and 17.5(25.8) for dryness. Median satisfaction with the study lenses was scored 9(2.8) on a 1-10 scale. In this study, satisfied wearers of comfilcon A reusable lens were refit with Verofilcon A daily disposable lenses and showed high satisfaction scores with the new lenses, showing that refitting these patients can allow patients to have lenses with more frequent replacement and maintain satisfaction with daily lens wear.

One-piece knitted embedded hang-needle sensor for shoulder posture recognition

Wearable products have significant applications in medical assistance, posture correction, and humancomputer interaction. In this study, we present a knitting method for a one-piece knitted embedded hang-needle sensor. This method involves simultaneously knitting conductive yarn into the sensing zone while creating the monitoring garment in a seamless manner. By implementing a tight hanging needle structure in the sensing zone design and adjusting knitting parameters, the effect of pre-stretching on the sensor caused by the base garment is minimized. Furthermore, integrating the sensing area of the hang-needle structure with the monitoring garment eliminates the need for additional sensor integration steps and simplifies the preparation process, resulting in reduced time and material costs. Moreover, the monitoring garment offers a comfortable wearing experience without any foreign body sensation and accurately captures the initial shoulder posture of the wearer.

Radiative cooling and anisotropic wettability in E-textile for comfortable biofluid monitoring

Long-term wearing comfort is essential for future advanced electronic textiles (e-textiles). Herein, we fabricate a skin-comfortable e-textile for long-term wearing experience on human epidermis. Such e-textile was simply fabricated through two different dip coating methods and single-side air plasma treatment, which couples radiative thermal and moisture management for biofluid monitoring. The silk-based substrate with improved optical properties and anisotropic wettability can provide a temperature drop of 1.4 °C under strong sunlight. Moreover, the anisotropic wettability of the e-textile can provide a dryer skin microenvironment by comparing with traditional fabric. The fiber electrodes weaving into the inner side of the substrate can noninvasively monitor multiple sweat biomarkers (i.e., pH, uric acid, and Na+). Such a synergistic strategy may pave a new path to design next-generation e-textiles with significantly improved comfort.

A qualitative analysis of denture wearing experience affecting the quality of life of older adults.

To explore how denture-related experiences affect older adults' quality of life using a qualitative assessment of the Oral Health Impact Profile for Edentulous individuals (OHIP-Edent). Twenty elderly individuals were interviewed before and 3months after delivering new complete dentures, using an open-ended interview guide based on the OHIP-Edent. Interviews were audio-recorded and transcribed. Data were open coded and thematically analyzed following a Grounded Theory approach. Findings were integrated and constantly compared to understand the interviewees' difficulties, beliefs, and perceptions. Three interconnected themes were developed: functional and psychosocial impairments, and coping strategies. Even when posed as an open-ended format, the wording of some OHIP-Edent items was confusing while others were not relevant to the respondents. New categories related to speaking, smiling, swallowing, emotional and functional coping emerged from the interviews. Interviewees adapted to chewing and swallowing difficulties through food avoidance, modification of food choice and preparation techniques, and changes in dietary behaviors. Denture wearing is a daily challenging experience that encompasses various functional and psychosocial aspects and sheds light on the need for addressing the coping strategies employed by patients, as the current OHIP-Edent items may not fully represent other deemed important aspects of the quality of life of individuals who wear dentures. Dentists must not solely rely on structured questionnaires to explore the impact of denture wearing and treatment outcomes. Clinicians can use a more holistic approach to comprehend older adults' experiences with dentures including advice about coping mechanisms, food preparation techniques, and meal planning.

Effects of different custom-made mouthguard palatal extensions on the stress-state of dentoalveolar structures: a 3D-FEA.

The present study aimed to simulate the influence of palatal extensions for custom-made mouthguards (MGs) on protecting dentoalveolar structures and to provide a theoretical basis for designing a comfortable MG. Based on finite element analysis (3D-FEA), five groups of maxillary dentoalveolar models of wearing MGs were established: no MG on palatal side (NP), on palatal gingival margin (G0), 2 mm from the palatal gingival margin (G2), 4 mm from the palatal gingival margin (G4), 6 mm from the palatal gingival margin (G6), and 8 mm from the palatal gingival margin (G8). A cuboid was created to simulate the solid ground impacted in falls, a gradually increasing force was applied from 0 to 500 N on the vertical ground, and the distribution and peak values of the Critical modified von-Mises stress, maximum principal stress, and displacement of dentoalveolar models were calculated. Stress distribution range, stress, and deformation peak value of dentoalveolar models increased as the impact strength increased, at 500 N. Maximum critical modified von-Mises stress, peak maximum principal stress and maximum displacement of dentoalveolar models G4, G3, G2, G1, G0, and NP were 154.5 MPa, 154.5 MPa, 154.4 MPa, 154.7 MPa, 154.4 MPa, and 154.7 MPa; 191.65 MPa, 192.11 MPa, 191.62 MPa, 191.81 MPa, 191.56 MPa, and 191.62 MPa; and 88.78 μm, 88.57 μm, 88.19 μm, 88.67 μm, 88.43 μm, and 89.04 μ, respectively. However, the position of the MG palatal edge had little effect on stress distribution, stress, and deformation peak values of the dentoalveolar models. Different extension ranges of the MG palatal edge have little effect on the protective effects of MGs on maxillary teeth and maxilla. An MG with palatal extension on the gingival margin is more appropriate than other models and may help dentists to design a suitable MG and increase its usage. MGs with palatal extensions on the gingival margin may provide a more comfortable wearing experience for individuals involved in sports and encourage increased MG usage.

Performance of a Silicone Hydrogel Daily Disposable Contact Lens among Wearers with Lens-related Dryness

Background: Addressing contact lens dryness continues to be a development goal of contact lens (CL) manufacturers. Objective: The objective of this study is to evaluate the clinical performance of kalifilcon A, a daily disposable silicone hydrogel (SiHy) CL, in subjects that experience dryness with their habitual planned-replacement SiHy CLs relative to a non-dry subgroup. Methods: A cohort of adapted planned-replacement SiHy CL wearers wore kalifilcon A lenses for at least 8 hours daily over two weeks. After one week of lens wear, subjects completed a survey regarding their lens wearing experience with respect to comfort and vision. Subsequently, subjects visited the clinics for the 2-week visit, during which the investigators completed a slit lamp exam and questionnaire regarding lens performance. Results: The evaluation included 180 subjects experiencing CL dryness with their habitual SiHy lenses and 213 subjects that did not. Both subgroups largely agreed with all comfort and vision attribute statements, and the dryness subgroup expressed higher levels of agreement with most comfort-related statements. Among habitual rewetting drop users, 73.9% in the dryness subgroup and 73.1% in the non-dry subgroup used drops less frequently while wearing kalifilcon A lenses. Investigators found no &gt; Grade 2 slit-lamp findings, nor differences between subgroups. Neither subgroup showed a change in ratings between visits, except for a significantly higher proportion of improvers in the non-dry subgroup for upper lid tarsal conjunctival abnormalities. Conclusion: The kalifilcon A lens performed well among habitual planned-replacement SiHy CLs wearers. Its unique chemistry can provide a more satisfying wear experience for SiHy lens wearers experiencing CL dryness.

Association of Locus Xq26.1–27.3 with Erosive Tooth Wear Phenotypes in a Group of Adolescents

Erosive tooth wear is a multifactorial condition of an increasing prevalence. There is a need for discovering individual genetic predisposition for the development of this condition. Considering that the chromosome X locus was previously shown to be associated with dental caries, the aim of the present study was to look for the association between this locus and erosive tooth wear when dietary habits are considered as a co-factor. Saliva samples, erosive wear experience data, and dietary information from 16- to 18-year-old dental patients (n = 705) were used. Genotyping analyses were performed, and thereafter, analyses considering diet and oral hygiene data, using logistic regression, with the assumption that erosive tooth wear is a complex gene-environment model. Genotypic analyses revealed an association between chromosome X marker rs1324156 and erosive tooth wear phenotype. Logistic regression analysis showed that, in the presence of less common allele of rs12687601 and rs1324156, erosive tooth wear more likely develops when associated with numerous dietary variables from the questionnaire. These results indicate that erosive tooth wear may be the result of gene-environment interactions.

Lightweight polyester fabric with elastomeric bismuth titanate composite for high-performing lead-free X-ray shielding

To protect the workers from overexposure to X-ray radiation, conventional lead (Pb)-based aprons are widely applied to many medical institutions and nuclear industries. However, these Pb-based aprons have many disadvantages such as heaviness, toxicity, and discomfort wearing experience, there is thus a strong demand for the replacement using lightweight, Pb-free, and flexible X-ray shielding materials. In this study, a new solution using a sandwich-structure composite (polyester fabric-elastomeric bismuth titanate composite-polyester fabric) is explored to develop the superior X-ray shielding materials. To demonstrate this concept, nanosized bismuth titanate (BTO) was used as an effective shielding component, which was blended with polydimethylsiloxane (PDMS) to form a PDMS/BTO composite. The sandwich-structure PDMS/BTO coated polyester fabric (SL-PDMS/BTO-PES) was then fabricated using 2 × coated PES fabrics and compressed together. X-ray transmission of these SL-PDMS/BTO-PES fabrics with an average thickness at 1.1 mm was measured at 80 kVp and 100 kVp, showing 0.35 mm Pb-equivalent X-ray shielding ability. Moreover, this SL-PDMS/BTO-PES was 42% lighter than 0.35 mm Pb sheet, indicating that this lightweight and flexible sandwich-structure coated PES textile can be potentially engineered in the future for replacing the conventional Pb-vinyl X-ray shielding clothing.

Preparation of Nylon-6 micro-nanofiber composite membranes with 3D uniform gradient structure for high-efficiency air filtration of ultrafine particles

Compared of traditional melt-blown nonwoven materials, micro-nanofiber composite membranes with uniform spatial gradient structure will be the development trend of high efficiency and low resistance filtration materials, especially against ultrafine particles with kinetic diameter less than 0.25 (PM0.25). Herein, Nylon-6 micro-nanofiber composite membranes (Nylon-6 FCMs) with three-dimensional (3D) uniform gradient structure were prepared by air jet spinning under the help of PEO. The fluffy 3D gradient structure possessed a uniform gradual pore gradient from large to small, ensuring the PM0.25 were captured by exact grading under high gas flow due to the form of special “trumpet-like” gas passage inside the membranes. The structure of Nylon-6 FCMs could be controlled and exhibited high tensile strength, good moisture permeability, excellent filtration performance. Among them, the FCM-1 with a uniform gradual pore gradient could achieve the optimal filtering performance with filtration efficiency (99.99 %) and pressure drop (144 Pa). The mask prepared using this Nylon-6 FCMs also displayed good protective effect with comparable air permeability (221.84 mm·s−1) and moisture permeability (181.84 g·m−2·h−1) compared of commercial melt-blown masks. Most importantly, this mask prepared still could maintain good filtration performance even in high temperature and high humidity environment, providing users more comfortable wearing experience and stable protection performance, especially under the current COVID-19 outbreak.