Construction of Janus structures on thin silk fabrics via misting for wet-thermal comfort and antimicrobial activity

Owing to their small fiber diameter (10-15 μm), silk fabrics are always thin (32-90 g m-2). Therefore, construction of the Janus surfaces of silk fabrics that possess excellent multifunctionality remains a formidable challenge. Herein, first, silk fabrics were grafted using glycidyltrimethylammonium chloride to form a superhydrophilic surface (G-side). Then, a unilateral hydrophobic surface (O-side) was readily fabricated by mist coating octadecyltrichlorosilane-functionalized SiO2 nanoparticles (NPs) to produce hierarchical surface textures. To prevent NP penetration from the G-side to the O-side, a "fireproof isolation" method was employed. Consequently, Janus silk fabrics (JanSFs) bearing asymmetric wettability were prepared, and their wetting gradient could be conveniently regulated. With the mist time ranging from 4 to 7 min, the unidirectional transport index and efficiency of the unidirectional water transport increased and decreased by 13.2 and 10.4 times, respectively. Sweat could be effectively drained away from human skin to ensure that the skin was dry and comfortable. Compared with the surface temperature of the raw fabric, the raw fabric of JanSFs increased by 2.7 °C. Furthermore, the breathability of JanSF was negligibly affected, and the outer O-side of the JanSF showed substantial antibacterial activity. This study is important for designing JanSFs that exhibit unidirectional water transport.

Comparison of three low-cost techniques to control fogging of sealed eyewear in a simulated operating room environment: A preliminary analysis

PURPOSE

In the current COVID pandemic, hermetically sealed eyewear is recommended for safe surgical practices to prevent eye contact with contaminated airborne particles or aerosols. These sealed eyewears definitely reduce the risk of contamination of eyes. However, there is a constant issue of fogging up of the inner surface that prevents good surgical visibility which can impair surgeons' performance and their ability to perform fine tasks, especially in operating rooms with temperature and humidity controlled as per the COVID guidelines. We investigated the effectiveness of surface-modified anti-fog polyethylene terephthalate(PET) films and the application of a detergent-based surfactant liquid, applied to the inner aspect of viewing frame, and addition of filtered vents in the prevention of fogging up of the protective eyewears in a simulated operating room environment.

METHODS

Ten volunteer orthopedic surgeons tested three modifications of a poly-hydrocarbon based hermetically sealed eyewear as a) application of a surface-modified anti-fog PET film on the inner aspect of eyewear, b) application of a detergent-based surfactant coating on the inner aspect of the protective eyewear, and c) addition of two filtered vents/holes on each side of the protective eyewear, covered with an N95 mask cutting. The testing was performed while completing a synthetic bone-based surgical task in a simulated operating room environment of 24-26° temperature and humidity between 40 and 70%, for a maximum of 2 h. The duration to the loss of clear visibility (ability to read a newspaper) and workable visibility (ability to perform the surgical task) was recorded for each volunteer.

RESULTS

The detergent-based surfactant provided the longest duration of clear visibility (69.3 ± 8.16 min) and the workable visibility was maintained for more than 2 h. The second best durations of clear visibility (31.9 ± 3.75 min) and workable visibility (41.6 ± 5.39 min) were provided by the surface-modified anti-fog PET film. The addition of the filtered vents provided only a marginal improvement in the visibility.

CONCLUSION

A detergent-based surfactant coating of the viewing surface provides a simple, inexpensive and effective solution to the problem of fogging of the protective eyewears. Besides this, the workable vision is maintained for a prolonged duration.

Inhaling alcohol vapour or mist: An international study of use, effects and harms

OBJECTIVES

To determine the prevalence, patterns of use and consequences of inhaling alcohol vapour or mist.

DESIGN

Cross-sectional survey recruiting an international non-probability sample of people who use alcohol and other drugs as part of the annual Global Drug Survey (GDS).

SETTING

Online questionnaire translated into 19 languages.

PARTICIPANTS

110,557 people took part in GDS2020 and 88,124 completed a question about inhaling alcohol in the last 12 months. The focus of this study is GDS2020 respondents who reported inhaling alcohol mist/vapour from a balloon in the last 12 months.

MAIN OUTCOMES

Last 12-month use of alcohol vapour, onset duration, intensity of effects, value for money compared with alcohol, and incidence of falls/injuries.

RESULTS

A total of 803 people reported the use of alcohol vapour in the last 12 months, with 51% of the sample coming from 3 countries: Australia, Denmark and England. Two-thirds were male, and they were more likely to be under 25. 45.7% reported that they were a bit/very drunk before they inhaled alcohol. 51.3% reported that the effects lasted for less than 5 mins. Both the intensity of effect and perceived value for money showed a normal distribution on a 10-point scale. 12.7% of respondents reported falling/injuring themselves.

CONCLUSION

Inhaling alcohol vapour appears to be more common amongst younger, higher-risk drinkers. The rapid onset of action and inability to titrate consumption to effect is a risk for acute injury. We consider that alcohol is harmful enough through oral consumption without adding to the risk of injury by offering such a potentially risky additional administration method.

Acinetobacter - the trojan horse of infection control?

BACKGROUND

Five cases of multi-resistant Acinetobacter baumanii (MRA) producing OXA-23 and OXA-51 occurred in a regional burn intensive care unit (BICU). Three were repatriated from other parts of the world (Dubai and Mumbai) and colonized on admission. Despite optimal precautions, two patients acquired MRA. Both had been nursed in the same room.

METHODS

Multi-disciplinary outbreak investigation of MRA in a regional BICU.

FINDINGS

The mechanism of transfer for the first case is thought to have been contaminated air from theatre activity releasing MRA bacteria into the communal corridor. No MRA patients went to theatre between the first and second acquired cases. The mechanism of transfer for the second case is thought to have been via a shower unit that was decontaminated inadequately between patients.

CONCLUSION

In an outbreak where contact precautions and environmental cleaning are optimal, it is important to give careful consideration to other mechanisms of spread. If there is a failure to do this, it is likely that the true causes of transmission will not be addressed and the problem will recur. It is recommended that burn theatres within burn facilities should be designed to operate at negative pressure; this is the opposite of normal operating theatre ventilation. Where showers are used, both the shower head and the hose should be changed after a patient with a resistant organism. The role of non-contact disinfection (e.g. hydrogen peroxide dispersal) should be reconsidered, and constant vigilance should be given to any 'trojan horse' item in the room.

Combination of aerosolized curcumin and UV-A light for the inactivation of bacteria on fresh produce surfaces

There is a critical unmet need to improve microbial safety of fresh fruits and vegetables. Current sanitation approaches cannot achieve >2 log inactivation of bacteria on fresh produce. Thus, there is a need to develop antimicrobial strategies that can consistently achieve >2 logs of bacterial inactivation on the surface of diverse fresh produce. Furthermore it is highly desired that these antimicrobial strategies have reduced environmental impact and are clean label solutions for food products. In this study, we evaluated the combination of curcumin and UV-A light radiation for the inactivation of inoculated E. coli O157:H7 and L. innocua bacterial cells on the surface of spinach, lettuce and tomatoes. Curcumin was deposited on the surface of fresh produce by either aerosolization or conventional spray-atomization methods before exposing the contaminated produce to UV-A light for 10 min (total light fluence of 20.4 kJ m-2). Results showed that the proposed combination of aerosolized or sprayed curcumin and UV-A light radiation can reduce the initial Escherichia coli O157:H7 and Listeria innocua load from 6 log CFU cm-2 to approximately 3 log CFU cm-2 on spinach, lettuce and tomato surfaces. Furthermore, there was no significant difference in bacterial reduction between the different types of inoculated fresh produce surfaces (P > .05). Interestingly, subsequent curcumin deposition and UV-A light exposure cycles were not able to further reduce the bacterial load below the observed threshold of approximately 3 log CFU cm-2. Lastly, the combination of aerosolized curcumin and UV-A light radiation did not affect the color or the texture of the treated fresh produce samples. The findings described in this study illustrate the potential of applying aerosolized or sprayed curcumin under UV-A light illumination to improve microbial safety of fresh produce products.

Effect of misting and wallowing cooling systems on milk yield, blood and physiological variables during heat stress in lactating Murrah buffalo

Background

Heat stress adversely affects the physiological and metabolic status, and the productive performance of buffalo.

Methods

The present study was conducted to explicate the effect of misting and wallowing cooling strategies during heat stress in lactating Murrah buffalo. The study was conducted for three months (May–July) of which first two months were hot dry and last month was hot humid. Eighteen lactating buffaloes, offered the same basal diet, were blocked by days in milk, milk yield and parity, and then randomly allocated to three treatments: negative control (no cooling), cooling by misting, and cooling by wallowing.

Results

The results showed higher (P < 0.05) milk yield in buffaloes of misting and wallowing group compared to control during the experimental period however wallowing was found more (P < 0.05) effective during July (hot humid period). Both the treatments resulted into significant (P < 0.05) reduction in rectal temperature (RT) and respiratory rate (RR) compared to control animals during study period whereas wallowing was found to be effective on pulse rate (PR) only during July. Both treatments were resulted in mitigating the heat stress mediated decrease in packed cell volume (PCV), lymphocytopnoea and neutrophilia whereas decrease in total erythrocyte count (TEC) and monocytes was only mitigated by wallowing. Heat load induced alteration in serum creatinine and sodium concentration was significantly (P < 0.05) ameliorated by misting and wallowing whereas aspartate aminotransferase, alkaline phosphatase and superoxide dismutase activity, and reactive oxygen species concentration could be normalized neither by misting nor by wallowing. The significant (P < 0.05) increment in serum cortisol and prolactin levels observed in June and July period in control animals was significantly (P < 0.05) prevented by misting and wallowing.

Conclusions

It can be concluded that misting and wallowing were equally effective in May and June (hot dry period) whereas wallowing was more effective during hot humid period in preventing a decline in milk production and maintaining physiological, metabolic, endocrine and redox homeostasis.