There is a lack of reported studies on how the long duration wearing of N95 respirators or surgical facemasks will affect the upper airway functions. Considering the frequency of mask wearing especially in hospitals a...There is a lack of reported studies on how the long duration wearing of N95 respirators or surgical facemasks will affect the upper airway functions. Considering the frequency of mask wearing especially in hospitals and during an outbreak of influenza, it is essential to have such data documented. Therefore, the current study is to establish the effect of long duration wearing of N95 and surgical facemasks on upper airway functions. 47 staffs of National University Hospital Singapore in 2013 were recruited. Each of the volunteers wore both N95 respirator and surgical facemask for 3 hours on two different days. During the period of mask wearing, relative airflow rates were recorded. Smell function test was carried out before and after mask wearing. The results show that no significant change of smell test score was found after removal of both the two types of masks. With N95 respirator, more air was breathed into the upper airways compared to surgical facemask.展开更多
The World Health Association and many governmental agencies recommend the wearing of facemasks by the general public to prevent the spread of COVID-19. It is believed that masks can significantly protect others and ma...The World Health Association and many governmental agencies recommend the wearing of facemasks by the general public to prevent the spread of COVID-19. It is believed that masks can significantly protect others and may offer some protection to the wearer. Although there are standards for FFRs, surgical masks, and recently for barrier face coverings, they all indicate the level of protection for the wearer. However, testing facial masks not at the point of inhalation, but at the source, the exhale, offers a new perspective on how to impede particle emissions. In this paper, the experimental results show that, although the barrier face covering is less effective than FFRs or surgical masks, it can reduce the concentration of aerosols downstream of the device. The results on barrier efficiency show a rapid decrease in effectiveness when the face covering is not sealed to the head. The barrier efficiency of two of the barrier face coverings tested is strongly dependent on leakage caused by the fit rather than the material. While some materials certainly are more effective than others in inhibiting particle penetration, an even more profound factor is the amount of leakage emitted from a mask. New approaches to fit and design in order to create a seal against leakage will become an important factor in combatting SARS-CoV-2.展开更多
AIM: To investigate the influence of non-oil 95(N95)/filtering facepiece 2(FFP2) facemask wear on retinal thickness, choroidal thickness(CT), retinal nerve fiber layer thickness(RNFLT), and ganglion cell layer thickne...AIM: To investigate the influence of non-oil 95(N95)/filtering facepiece 2(FFP2) facemask wear on retinal thickness, choroidal thickness(CT), retinal nerve fiber layer thickness(RNFLT), and ganglion cell layer thickness(GCLT) in healthy subjects.METHODS: In this prospective study, 53 healthy participants who used FFP2/N95 facemask were enrolled. Participants underwent optical coherence tomography imaging before and at 1 and 4h following FFP2/N95 facemask wear. The last imaging session was performed 1h after FFP2/N95 removal. Retinal thickness, CT, RNFLT, and GCLT were assessed at each session. Vital parameters were also assessed. RESULTS: The pulse rate of the subjects significantly decreased at 1 and 4h compared to baseline values(P<0.05). No significant changes in retinal thickness, RNFLT, and GCLT were observed in the study. CT profile showed a significant increase at all measured locations except 1-mm temporal, 1-mm inferior and 2-mm inferior points following FFP2/N95 wear which turned to baseline values after FFP2/N95 removal. Pulse rate and CT changes at 4h were significantly correlated(P<0.05).CONCLUSION: Parasympathetic activation during FFP2/N95 facemask wear might have a role on elevated CT measurements in healthy individuals by virtue of increased choroidal blood flow.展开更多
From December 25,2019 to January 31,2020,33 cases of the coronavirus disease 2019(COVID-19)were identified in the Department of Respiratory and Critical Care Medicine of Zhongnan Hospital of Wuhan University,China,yet...From December 25,2019 to January 31,2020,33 cases of the coronavirus disease 2019(COVID-19)were identified in the Department of Respiratory and Critical Care Medicine of Zhongnan Hospital of Wuhan University,China,yet none of the affiliated HCWs was infected.Here we analyzed the infection control measures used in three different departments in the Zhongnan Hospital of Wuhan University and correlated the measures with the corresponding infection data of HCWs affiliated with these departments.We found that three infection control measures,namely the isolation of the presumed positive patients,the use of facemasks and intensified hand hygiene play important roles in preventing nosocomial transmission of COVID-19.展开更多
Despite the omnipresence of facemasks in the ongoing COVID-19 pandemic,recent studies on their sociopolitical aspects remain insufficient.This article conducts a genealogical study that investigates the emergence of t...Despite the omnipresence of facemasks in the ongoing COVID-19 pandemic,recent studies on their sociopolitical aspects remain insufficient.This article conducts a genealogical study that investigates the emergence of two differing masking strategies in two epidemic events in Chinese history.First,during the Manchurian plague 1910/11,it shows how the germ theory and historical anecdotes made anti-plague masks thinkable and practicable as a solution not only for airborne contagion but also for the biopolitical problem of‘unhygienic’population.In the second part,the analytical focus is shifted to the emergence of collective mask-wearing practices during SARS 2002/03 from the vantage point of subjectification.Facemasks then became a symbol of care in the neoliberal regime of responsibilization.This article concludes by arguing for a rethinking of facemasks as actants who actively participate in the constitution of the world we share.展开更多
The COVID-19 pandemic encouraged the use of plastic-based personal protective equipment (PPE), which aidedgreatly in its management. However, the increased production and usage of these PPEs put a strain on the enviro...The COVID-19 pandemic encouraged the use of plastic-based personal protective equipment (PPE), which aidedgreatly in its management. However, the increased production and usage of these PPEs put a strain on the environment,especially in developing and underdeveloped countries. This has led various researchers to study low-costand effective technologies for the recycling of these materials. One such material is disposable facemasks. However,previous studies have only been able to engage electrically powered reactors for their thermochemical conversion,which is a challenge as these reactors cannot be used in regions with an insufficient supply of electricity. In thisstudy, the authors utilized a biomass-powered reactor for the conversion of waste disposable facemasks and almondleaves into hybrid biochar. The reactor, which is relatively cheap, simple to use, environmentally friendly, and modifiedfor biochar production, is biomass-powered. The co-carbonization process, which lasted 100 min, produced a 46%biochar yield, which is higher than previously obtained biochar yields by other researchers. The biochar thus obtainedwas characterized to determine its properties. FTIR analysis showed that the biochar contained functional groupssuch as alkenes, alkynes, hydroxyls, amines, and carbonyls. The EDX analysis revealed that the biochar was primarilymade of carbon, tellurium, oxygen, and calcium in the ratios of 57%, 19%, 9%, and 7%, respectively. The inclusion ofthe facemask decreased the surface area and porosity of the biochar material, as evidenced by its surface area andpore characteristics.展开更多
文摘There is a lack of reported studies on how the long duration wearing of N95 respirators or surgical facemasks will affect the upper airway functions. Considering the frequency of mask wearing especially in hospitals and during an outbreak of influenza, it is essential to have such data documented. Therefore, the current study is to establish the effect of long duration wearing of N95 and surgical facemasks on upper airway functions. 47 staffs of National University Hospital Singapore in 2013 were recruited. Each of the volunteers wore both N95 respirator and surgical facemask for 3 hours on two different days. During the period of mask wearing, relative airflow rates were recorded. Smell function test was carried out before and after mask wearing. The results show that no significant change of smell test score was found after removal of both the two types of masks. With N95 respirator, more air was breathed into the upper airways compared to surgical facemask.
文摘The World Health Association and many governmental agencies recommend the wearing of facemasks by the general public to prevent the spread of COVID-19. It is believed that masks can significantly protect others and may offer some protection to the wearer. Although there are standards for FFRs, surgical masks, and recently for barrier face coverings, they all indicate the level of protection for the wearer. However, testing facial masks not at the point of inhalation, but at the source, the exhale, offers a new perspective on how to impede particle emissions. In this paper, the experimental results show that, although the barrier face covering is less effective than FFRs or surgical masks, it can reduce the concentration of aerosols downstream of the device. The results on barrier efficiency show a rapid decrease in effectiveness when the face covering is not sealed to the head. The barrier efficiency of two of the barrier face coverings tested is strongly dependent on leakage caused by the fit rather than the material. While some materials certainly are more effective than others in inhibiting particle penetration, an even more profound factor is the amount of leakage emitted from a mask. New approaches to fit and design in order to create a seal against leakage will become an important factor in combatting SARS-CoV-2.
文摘AIM: To investigate the influence of non-oil 95(N95)/filtering facepiece 2(FFP2) facemask wear on retinal thickness, choroidal thickness(CT), retinal nerve fiber layer thickness(RNFLT), and ganglion cell layer thickness(GCLT) in healthy subjects.METHODS: In this prospective study, 53 healthy participants who used FFP2/N95 facemask were enrolled. Participants underwent optical coherence tomography imaging before and at 1 and 4h following FFP2/N95 facemask wear. The last imaging session was performed 1h after FFP2/N95 removal. Retinal thickness, CT, RNFLT, and GCLT were assessed at each session. Vital parameters were also assessed. RESULTS: The pulse rate of the subjects significantly decreased at 1 and 4h compared to baseline values(P<0.05). No significant changes in retinal thickness, RNFLT, and GCLT were observed in the study. CT profile showed a significant increase at all measured locations except 1-mm temporal, 1-mm inferior and 2-mm inferior points following FFP2/N95 wear which turned to baseline values after FFP2/N95 removal. Pulse rate and CT changes at 4h were significantly correlated(P<0.05).CONCLUSION: Parasympathetic activation during FFP2/N95 facemask wear might have a role on elevated CT measurements in healthy individuals by virtue of increased choroidal blood flow.
文摘From December 25,2019 to January 31,2020,33 cases of the coronavirus disease 2019(COVID-19)were identified in the Department of Respiratory and Critical Care Medicine of Zhongnan Hospital of Wuhan University,China,yet none of the affiliated HCWs was infected.Here we analyzed the infection control measures used in three different departments in the Zhongnan Hospital of Wuhan University and correlated the measures with the corresponding infection data of HCWs affiliated with these departments.We found that three infection control measures,namely the isolation of the presumed positive patients,the use of facemasks and intensified hand hygiene play important roles in preventing nosocomial transmission of COVID-19.
文摘Despite the omnipresence of facemasks in the ongoing COVID-19 pandemic,recent studies on their sociopolitical aspects remain insufficient.This article conducts a genealogical study that investigates the emergence of two differing masking strategies in two epidemic events in Chinese history.First,during the Manchurian plague 1910/11,it shows how the germ theory and historical anecdotes made anti-plague masks thinkable and practicable as a solution not only for airborne contagion but also for the biopolitical problem of‘unhygienic’population.In the second part,the analytical focus is shifted to the emergence of collective mask-wearing practices during SARS 2002/03 from the vantage point of subjectification.Facemasks then became a symbol of care in the neoliberal regime of responsibilization.This article concludes by arguing for a rethinking of facemasks as actants who actively participate in the constitution of the world we share.
文摘The COVID-19 pandemic encouraged the use of plastic-based personal protective equipment (PPE), which aidedgreatly in its management. However, the increased production and usage of these PPEs put a strain on the environment,especially in developing and underdeveloped countries. This has led various researchers to study low-costand effective technologies for the recycling of these materials. One such material is disposable facemasks. However,previous studies have only been able to engage electrically powered reactors for their thermochemical conversion,which is a challenge as these reactors cannot be used in regions with an insufficient supply of electricity. In thisstudy, the authors utilized a biomass-powered reactor for the conversion of waste disposable facemasks and almondleaves into hybrid biochar. The reactor, which is relatively cheap, simple to use, environmentally friendly, and modifiedfor biochar production, is biomass-powered. The co-carbonization process, which lasted 100 min, produced a 46%biochar yield, which is higher than previously obtained biochar yields by other researchers. The biochar thus obtainedwas characterized to determine its properties. FTIR analysis showed that the biochar contained functional groupssuch as alkenes, alkynes, hydroxyls, amines, and carbonyls. The EDX analysis revealed that the biochar was primarilymade of carbon, tellurium, oxygen, and calcium in the ratios of 57%, 19%, 9%, and 7%, respectively. The inclusion ofthe facemask decreased the surface area and porosity of the biochar material, as evidenced by its surface area andpore characteristics.
