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Poor-fitting face masks can allow particles, including the coronavirus disease 2019 virus, to spread. Reproducible methods for fit testing face masks are scarce and many require sophisticated testing equipment. The purpose of this experimental research was twofold: (a) to develop a simple and reproducible method for assessing face mask fit at key facial areas; and (b) to utilize the method to examine the fit of various commercially available fabric-based face masks on different head shapes at key facial areas. The mask fit test method was developed to assess face mask fit in six key face mask/head correspondence areas: bridge of nose; cheek/area below the eyes (including the nasolabial fold); chin; ear loops; sides of mask near the ears; and sides of nose. Proper fit was indicated when no excessive tightness or gaping occurred. The mask fit test method was used to assess the fit of eight types of commercially available face masks on five three-dimensional printed headforms. The five headforms were created from the National Institute for Occupational Safety and Health standards for head shapes and sizes. Six evaluators utilized the mask fit test method to score the eight face masks on each headform. Overall, only two face masks had proper fit for the majority of the headforms. All other face masks exhibited loose or gaping fit. General trends included superior fit for larger headforms and poor fit for all face masks evaluated on the smaller phantom. Facial areas that commonly produced large gaps were the bridge of nose, cheeks, and sides of nose. Thus, this study recommends improved design and sizing of face masks to properly fit a larger segment of the population.

Non-medical fabric masks, recommended by the Centers for Disease Control and Prevention and the World Health Organization, are available in various fabrics. There is limited research on the overall effectiveness of fabrics used to make masks. The purpose of this study was to assess fabrics commonly used in non-medical masks against their ability to mitigate the spread of COVID-19 based on the size and throughput of aerosols and particles (−1. FE results are lower than previously reported research with dP and Q factors within international guidelines. Using non-medical fabric masks as the sole mitigation strategy is not effective. It is critical to combine non-medical fabric masks with physical distancing to slow the spread of COVID-19 further.

Today, athleisure is one of the key trends in the fashion industry combining both casual style with health enthusiastic appeal creating a billion-dollar industry. Athleisure is the combining of act...

Background: Wearable technology is used by clinicians and researchers and play a critical role in biomechanical assessments and rehabilitation. Objective: The purpose of this research is to validate a soft robotic stretch (SRS) sensor embedded in a compression knee brace (smart knee brace) against a motion capture system focusing on knee joint kinematics. Methods: Sixteen participants donned the smart knee brace and completed three separate tasks: non-weight bearing knee flexion/extension, bodyweight air squats, and gait trials. Adjusted R2 for goodness of fit (R2), root mean square error (RMSE), and mean absolute error (MAE) between the SRS sensor and motion capture kinematic data for all three tasks were assessed. Results: For knee flexion/extension: R2 = 0.799, RMSE = 5.470, MAE = 4.560, for bodyweight air squats: R2 = 0.957, RMSE = 8.127, MAE = 6.870, and for gait trials: R2 = 0.565, RMSE = 9.190, MAE = 7.530 were observed. Conclusions: The smart knee brace demonstrated a higher goodness of fit and accuracy during weight-bearing air squats followed by non-weight bearing knee flexion/extension and a lower goodness of fit and accuracy during gait, which can be attributed to the SRS sensor position and orientation, rather than range of motion achieved in each task.

Compression socks are used by a very diverse group of individuals and may potentially have a greater impact on physically diminished or impaired individuals as opposed to healthy individuals. The purpose of this study was to compare the effects of sub-clinical (SC) and clinical (CL) compression socks among healthy (CON), copers (COP), and individuals with chronic ankle instability (CAI). Postural stability was evaluated in 20 participants (11 males and 9 females) using Balance Tracking System Balance platform (BTrackS™) during the modified clinical test of sensory integration in balance (mCTSIB) and limits of stability (LOS) tests. Postural sway parameters were analyzed using a mixed model repeated measures analysis of variance 3 (group: CON, COP, and CAI) by 3 (compression condition: BF, SC, and CL) × 4 (balance condition: EO, EC, EOF, and ECF) for mCTSIB and a 3 (group: CON, COP, and CAI) by 3 (compression condition: BF, SC, CL) × 4 (balance condition: FL, BL, BR, FR) for LOS. Results revealed significantly greater postural stability with both SC and CL compression socks when compared to barefoot conditions. However, no significant differences were observed among groups for compression socks grades. Both SC and CL compression socks may be effective in increasing postural stability.

Soft robotic sensors, a class of pliable, embeddable sensors, are well-suited for applications in wearable technology because of their ease of integration with common clothing articles. The suitability of soft robotic sensors for estimation of human joint angles has been proven; this research represents another step towards development of a reliable laboratory data collection platform for the human ankle joint complex. In this research, the accuracy and repeatability of a newly-developed wearable prototype are evaluated as a potential replacement for camera-based motion capture by measuring differences between simultaneously collected motion capture and stretch sensor data. The accuracy of these measurements is compared to measurements collected using a previous prototype for validation. Results show that the newly-developed prototype is capable of joint angle estimation within 1.86° mean-absolute-error during complex, dynamic movements and that wearing shoes over the sock prototype does not significantly degrade performance.

The purpose of this study is to compare masks (non-medical/fabric, surgical, and N95 respirators) on filtration efficiency, differential pressure, and leakage with the goal of providing evidence to improve public health messaging. Masks were tested on an anthropometric face filtration mount, comparing both sealed and unsealed. Overall, surgical and N95 respirators provided significantly higher filtration efficiency (FE) and differential pressure (dP). Leakage comparisons are one of the most significant factors in mask efficiency. Higher weight and thicker fabric masks had significantly higher filtration efficiency. The findings of this study have important implications for communication and education regarding the use of masks to prevent the spread of COVID-19 and other respiratory illnesses, specifically the differences between sealed and unsealed masks. The type and fabric of facial masks and whether a mask is sealed or unsealed has a significant impact on the effectiveness of a mask. Findings related to differences between sealed and unsealed masks are of critical importance for health care workers. If a mask is not completely sealed around the edges of the wearer, FE for this personal protective equipment is misrepresented and may create a false sense of security. These results can inform efforts to educate health care workers and the public on the importance of proper mask fit.

In this study, 100% polyester mesh fabrics were used as ham nets. The nets were treated with 40% propylene glycol (PG), 1% propylene glycol alginate (PGA), and 1% carrageenan. The treated and untreated nets were evaluated to determine any significant changes in terms of mechanical properties. Fabric weight (ASTM D3776), elastic properties (BS EN 14704-1:2005), abrasion resistance (ASTM D4966) and breaking strength (ASTM D5034-09) were tested. The morphology of 100% polyester fiber was also observed by scanning electron microscopy (SEM) images. Surface morphology of both treated and untreated fabric was also observed. No significant changes occurred in the mechanical properties that would affect the dry-cured ham aging process. Treated samples were stronger than untreated samples with respect to abrasion resistance, weight of the fabric in unit area (GSM), and tensile strength. This study indicates that these nets could be used to age dry-cured hams as part of a methyl bromide replacement strategy.

The purpose of this study is to compare masks (non-medical/fabric, surgical, and N95 respirators) on filtration efficiency, differential pressure, and leakage with the goal of providing evidence to improve public health messaging. Masks were tested on an anthropometric face filtration mount comparing both sealed and unsealed. Overall, surgical and N95 respirators provided significantly higher for filtration efficiency and differential pressure. Leakage comparisons are one of the most significant factors in mask efficiency. Higher weight and thicker fabric masks had significantly higher filtration efficiency. The findings of this study have important implications for communication and education regarding the use of masks to prevent the spread of COVID-19 and other respiratory illnesses specifically the differences between sealed and unsealed masks. One-Sentence Summary: The type and fabric of facial masks and whether a mask is sealed or unsealed has a significant impact on the effectiveness of a mask.

Standards for the fatigue testing of wearable sensing technologies are lacking. The majority of published fatigue tests for wearable sensors are performed on proof-of-concept stretch sensors fabricated from a variety of materials. Due to their flexibility and stretchability, polymers are often used in the fabrication of wearable sensors. Other materials, including textiles, carbon nanotubes, graphene, and conductive metals or inks, may be used in conjunction with polymers to fabricate wearable sensors. Depending on the combination of the materials used, the fatigue behaviors of wearable sensors can vary. Additionally, fatigue testing methodologies for the sensors also vary, with most tests focusing only on the low-cycle fatigue (LCF) regime, and few sensors are cycled until failure or runout are achieved. Fatigue life predictions of wearable sensors are also lacking. These issues make direct comparisons of wearable sensors difficult. To facilitate direct comparisons of wearable sensors and to move proof-of-concept sensors from “bench to bedside”, fatigue testing standards should be established. Further, both high-cycle fatigue (HCF) and failure data are needed to determine the appropriateness in the use, modification, development, and validation of fatigue life prediction models and to further the understanding of how cracks initiate and propagate in wearable sensing technologies.

Textile and electronic components are critical elements of most wearable technologies (wearables); both components deteriorate at different rates depending on factors of use, care, and user handling. The differences in mechanical performance characteristics (MPC) (i.e., abrasion, elongation, and bursting strength) of these components create a challenge for researchers and product designers to develop user-centric and economical wearables. For example, athletic wearables made of nylon/spandex knit blends exhibit drastically different MPC from minimal fiber content changes (1- 10%). However, the wearable's end-use remains constant. This article presents ideas and methods for testing MPC and how to evaluate results for different end-use cases. Designing for end-user activities also highlights these performance differences because specific, end-uses drive textiles design, which may or may not be the wearable design's end-use. Three American Society for Testing and Materials (ASTM) test methods were used to test MPC of athletic fabrics and soft robotic sensors (SRS) to determine the abrasion resistance, elongation, and bursting strength of these components and two-tail ttest comparisons were performed on the results. The SRS's durability is less than the textiles they are integrated into, and with no standards for MPC testing on SRS, it can be unclear how long a sensor will last. Such methods need to be developed so product developers can find efficient combinations of fibers and electronic components to ensure user-centric functionality, wearer comfort, extended product longevity, and overall consumer satisfaction.

Research surrounding the mandated use of non-medical fabric masks is inconsistent and often confusing when compared to the standard N95. A recently published standard from ASTM International and the Centers for Disease Control and Prevention attempts to normalize evaluation procedures. The purpose of this study is to conduct a preliminary evaluation of the new methods for testing filtration efficiency of masks outlined by ASTM International F3502, where results can be directly compared to standards outlined for non-medical fabric masks. Eleven consumer non-medical fabric masks were tested for filtration efficiency and airflow resistance using a face filtration mount in accordance with the newly released ASTM International standard for facial barriers. The mean FE% (SD) ranged from 0.46% (0.44) to 11.80% (2.76) with the 3-layer athletic mesh having the highest performance and the highest deviations. All the masks tested following the procedure failed to meet to minimum FE of 20%, however all masks performed below the minimum upper limits for airflow resistance. Using a non-medical fabric masks as the sole mitigation strategy may not be as effective, as previously reported. With efforts to standardize and regulate the non-medical fabric mask market, this study demonstrates a variety of currently available consumer mask products do not meet the minimum standards nor are these remotely close to the standards of surgical or N95 masks.

PNNL’s most recent single-component diamine CO2BOL derivative, 2-EEMPA, is an attractive post- combustion carbon capture solvent. This solvent can be configured to achieve regeneration energies as low as 2.0 GJ/tonne CO2 when configured with advanced heat integration, and total capture costs as low as $47.1/tonne CO2 when using a two-stage flash configuration. 2-EEMPA has been shown to be chemically durable, exhibits little foaming, and maintains a steady-state water loading of 1.6 wt%, as demonstrated on continuous flow testing with simulated flue gas. 2-EEMPA is potentially capable of thermally cracking heat-stable salts from NOx and SOx using PNNL’s polarity-swing assisted regeneration process. Building off of the promising behaviour of 2-EEMPA we conclude that by focusing future research areas on remaining cost-of-capture drivers, further improvements to water- lean formulations could be possible.

The objective of this research was to evaluate if chitosan-containing food-grade coatings can control Tyrophagus putrescentiae growth without affecting the sensory attributes of dry-cured hams. Food-grade coating treatments included (1) 0.3% chitosan (CH), (2) 0.6% CH, (3) 0.3% CH + 10% propylene glycol (PG), (4) 0.3% CH + 1% xanthan gum (XG), (5) 0.3% CH + 1% XG + 10% PG, (6) 0.3% CH + 1% carrageenan (CG) + 1% propylene glycol alginate (PGA), and (7) 0.3% CH + 1% CG + 1% PGA + 10% PG. Each coating solution was coated on ham cubes (2.54 × 2.54 × 2.54 cm3, n = 5/treatment) or infused in ham nets and dry-cured ham cubes were wrapped in the ham nets prior to inoculation with 20 adult mites. A randomized complete block design with three replications was utilized to evaluate the efficacy of treatments at controlling mite growth on dry-cured ham. When CH was mixed with XG (0.3% CH + 10% PG + 1% XG, and 0.3% CH + 1% XG) and infused into a net, fewer mites (15.7 and 21.0 mites) were on the ham cubes (P

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