Co-Combustion Investigation of Wood Pellets Blended with FFP2 Masks: Analysis of the Ash Melting Temperature

The COVID-19 pandemic brought a period of high consumption of protective masks and an increase in their waste. Therefore, it was necessary to look at possibilities for their disposal. This article is focused on the disposal of FFP2 masks in the form of pellets blended with sawdust. Further, their ash melting behavior was observed. The method of ash preparation can impact the resulting values of melting temperatures. Therefore, this article investigates the resulting values of ash melting temperatures determined during different ash preparations, such as temperatures (550 °C and 815 °C) and ash size (non-sifted, smaller than 50 µm and 100 µm). All measured deformation temperatures were higher than 1100 °C and even higher than 1200 °C for some samples. Moreover, the presence of FFP2 masks in pellets only insignificantly affected the values of melting temperatures compared to pure wood pellets. The measured values also showed that increasing the temperature of ash preparation from 550 to 815 °C can increase the resulting values of melting temperature. The most significant proportion of the fraction size on the resulting melting temperatures was observed for beech with 5% and 10% of masks at an ash temperature of 550 °C and for spruce with 10% of masks at an ash temperature of 815 °C. © 2023 by the authors.

The Relationship between Wearing Protective Masks and Poor Oral Health

Since the beginning of the COVID-19 pandemic, the number of people wearing masks in everyday life has increased. At the same time, there has been a noticeable rise in the amount of patients with bad breath (foe-tor ex ore), gingivitis, caries, and xerostomia. The appearance of these symptoms and diseases caused by wearing a mask is designated by the term mask mouth. The aim of this article is to establish the link between wearing protective masks and deteriorating oral health. From the conducted research, it has been es-tablished that wearing a surgical mask over a long period of time leads to reduced air exchange in the mask and "recycling" of exhaled air. This leads to inhalation of air with increased CO2 content and increase in pCO2 in the blood, which is subsequently compensated by rapid and deep breathing in most cases through the mouth. The goal is to exhale the accumulated CO2. As the mask reduces air exchange, the level of CO2 in the mask remains relatively high. Prolonged breathing through the mouth often leads to xerostomia. Saliva is known to have protective functions against the development of bacteria in the oral cavity through its an-tibacterial properties. Xerostomia can be a prerequisite for the development of various diseases of bacterial origin, such as gingivitis. Furthermore, oral respiration leads to an increase in temperature and CO2 in the air in the mask and a decrease in pH in the oral cavity, which are optimal conditions for biofilm formation, plaque buildup, development of most bacteria, e.g., S. mutans, which is the main cause of caries.Copyright © 2022, Bulgarian-American Center. All rights reserved.

Electrospun PVB/AVE NMs as mask filter layer for win-win effects of filtration and antibacterial activity.

The COVID-19 pandemic has caused serious social and public health problems. In the field of personal protection, the facial masks can prevent infectious respiratory diseases, safeguard human health, and promote public safety. Herein, we focused on preparing a core filter layer for masks using electrospun polyvinyl butyral/apocynum venetum extract nanofibrous membranes (PVB/AVE NMs), with durable interception efficiency and antibacterial properties. In the spinning solution, AVE acted as a salt to improve electrical conductivity, and achieve long-lasting interception efficiency with adjustable pore size. It also played the role of an antibacterial agent in PVB/AVE NMs to achieve win-win effects. The hydrophobicity of PVB-AVE-6% was 120.9° whereas its filterability reached 98.3% when the pressure drop resistance was 142 Pa. PVB-AVE-6% exhibited intriguing properties with great antibacterial rates of 99.38% and 98.96% against S. aureus and E. coli, respectively. After a prolonged usability test of 8 h, the filtration efficiency of the PVB/AVE masks remained stable at over 97.7%. Furthermore, the antibacterial rates of the PVB/AVE masks on S. aureus and E. coli were 96.87% and 96.20% respectively, after using for 2 d. These results indicate that PVB/AVE NMs improve the protective performance of ordinary disposable masks, which has certain application in air filtration.

Changes in Adolescent Hygiene Habits Caused by the COVID-19 Pandemic

The aim of this study was to examine and determine hygiene habits in the adolescent population depending on whether the Covid 19 pandemic affected the improvement of hygiene habits in the same population. The research is designed as a cross-sectional study. A questionnaire created using the Google Docs platform was used as an instrument. The sample consisted of 89 respondents of both sexes, aged 18 to 23 years. The analysis shows that there is a difference in maintaining hygienic habits before and after the introduction of the state of emergency. In 20.22% of cases, hygienic habits were better during the state of emergency, and after the mitigation of measures, compared to the period before the introduction of the state of emergency, and in 5.62% of respondents hygienic habits were worse, while in 74.16% of respondents there were no change in hygienic habits. The analysis of the use of disinfectants and masks shows that 60.68% of respondents used disinfectants and masks more often after mitigation of emergency measures compared to the period before the introduction of the state of emergency, 5.62% of respondents used less, while in 33.70 % of respondents there were no changes in the use of disinfectants and masks.The results of this study show a positive relationship between hygiene habits before and during the Covid 19 pandemic, and after mitigation, as well as between the use of disinfectants and masks before and during the Covid 19 pandemic, and after mitigation, which justifies further research in this area. [ FROM AUTHOR] Copyright of Serbian Journal of Experimental & Clinical Research is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Proposed approach to improve facial recognition techniques for occluded faces by Covid-19 mask protection

Wearing protective masks has become commonplace in several countries as a result of the epidemic connected to the Covid-19 virus. Wearing a mask obscures a considerable part of the face, making some facial recognition techniques difficult to complete and obstructing the operation of various identifying systems, such as access control systems. In this paper, we offer an original approach that allows many face recognition systems to continue to identify persons even when wearing protective masks. The proposed approach is mainly based on the prior use of skin detection techniques. We validated our method using the Eigenfaces method by the FEI database, which we supplemented with faces wearing protective masks. The evaluation results of our approach are very satisfactory. © 2022 Elsevier B.V.. All rights reserved.

Analysis of Trends and Challenges of a Worldwide Solid Waste Management with Emphasis on Covid-19 Pandemic-A Review

Low collection coverage, lack of a safe and appropriate destination for all generated waste and pollution caused by inadequate waste disposal procedures are probably one of the most significant threats in the current decade (2021-2030). At the beginning of 2020, a new and unforeseen challenge emerged-the COVID-19 pandemic. This article provides a brief overview of the state of waste management in the world, identifying significant challenges that arose during the pandemic. As the situation changed daily in all regions of the world, many local authorities were obliged to react urgently and adjust the current way of waste management. People's habits have changed and the mandatory wearing of protective masks has increased the daily amount of plastic waste worldwide by approximately 21 000+ tons. This represented an additional burden for already under capacitated waste management systems. Also, waste collected from households in many parts of the world had to be treated as medical waste due to the COVID-19 positive people. There was a drastic increase in the daily amount of generated medical waste due to this, which in some cases was up to 6 times higher than usual. © 2022, Strojarski Facultet. All rights reserved.

The use of protective masks and the level of arterial oxygen saturation at rest and after exercise.

BACKGROUND: Studies of influenza, and human coronaviruses provide evidence that the use of a medical mask can prevent the spread of infectious droplets from an infected person to someone else. After global public health emergency of coronavirus SARS-CoV-2 causing illness of COVID-19 was changing frequency of wearing a mask. Therefore, study was undertaken to assess whether the use of protective masks affects the level of oxygen saturation during rest and during exercise. MATERIAL AND METHODS: The test consisted of a non-invasive measurement of oxygen saturation by percutaneous determination of arterial oxygen saturation with the use of the pulse oximeter. Oxygen saturation was measured during rest and after physical exertion performed without a protective mask (2 types of masks were used: surgical and FFP2), as well as during rest and after physical exertion performed with the use of a protective mask. The analysis of the oxygen saturation, heart rate, blood pressure and respiratory rate included data on 48 subjects. RESULTS: Comparing the post-exercise and pre-exercise values showed a significant difference between all of them. There were no differences found in any variables according to the mask/no-mask status. CONCLUSIONS: A short-term physical exercise performed in a group of healthy young people using protective masks did not affect oxygen saturation, heart rate, blood pressure and respiratory rate. Med Pr. 2022;73(4).

Plastic Waste Management towards Energy Recovery during the COVID-19 Pandemic: The Example of Protective Face Mask Pyrolysis

This paper presents an assessment of the impact of the COVID-19 pandemic on the waste management sector, and then, based on laboratory tests and computer calculations, indicates how to effectively manage selected waste generated during the pandemic. Elemental compositions—namely, C, H, N, S, Cl, and O—were determined as part of the laboratory tests, and the pyrolysis processes of the above wastes were analysed using the TGA technique. The calculations were performed for a pilot pyrolysis reactor with a continuous flow of 240 kg/h in the temperature range of 400–900◦ C. The implemented calculation model was experimentally verified for the conditions of the refuse-derived fuel (RDF) pyrolysis process. As a result of the laboratory tests and computer simulations, comprehensive knowledge was obtained about the pyrolysis of protective masks, with particular emphasis on the gaseous products of this process. The high calorific value of the pyrolysis gas, amounting to approx. 47.7 MJ/m3, encourages the management of plastic waste towards energy recovery. The proposed approach may be helpful in the initial assessment of the possibility of using energy from waste, depending on its elemental composition, as well as in the assessment of the environmental effects. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

DIY Face Mask Effectiveness Against COVID-19

This paper addresses the question of how effective Do It Yourself (DIY) Personal Protective Equipment (PPE), i.e. face masks, are within the general population in mitigating the spread of COVID-19. It references studies comparing the effectiveness of various materials in DIY masks alongside surgical masks and respirators. This is associated with the Department of Defenses COVID-19 announcement for all Total Force members (military personnel, civilian employees, contractors and their family members) to wear a cloth face covering in public settings where social-physical distancing measures are difficult to maintain, especially in areas of significant community-based transmission. Studies have shown that holistically given a variety of factors that are discussed in depth in this paper a single layer pillowcase or a 100% cotton t-shirt are the most suitable household materials for an improvised (DIY) face mask. This is due to their breathability, fit factor, and their ability to reduce viral particle transmission by up to 50%. In general, using any type of face mask can decrease viral transmission. However, it is important not to focus on a single intervention in the case of a pandemic, but rather to integrate all effective interventions for optimal protection.3 A DIY face mask will not completely eliminate the possibility of infection with COVID-19, particularly given that there are multiple routes of transmission. But the underlying consensus of all research suggests that DIY cloth facemasks are better than nothing at all. It is vital to note that all DIY face masks, regardless of the efficiency of their filtration or seal, will only have partial effectiveness on their own. They must be used in conjunction with other preventative measures, which include: isolation of infected individuals, immunization, maintaining healthy eating/fitness standards, cough and respiratory etiquette, and regular hand hygiene. 2,3,8,14

Using COVID-19 Masks Dataset to Implement Deep Convolutional Neural Networks For Facial Emotion Recognition

In light of the novel pandemic called COVID-19, the world has been instructed to wear protective facial masks to limit its spread. Doing so has reduced the effectiveness of traditional facial recognition technologies, especially in processing human facial emotions. This has rendered the usage of such technology obsolete in managing facial databases, relying on it for security purposes, and so on. It is then necessary to enhance the current generation of facial recognition to adapt to the protective masks. Speaking of the current facial recognition generation, most of its complex iterations heavily rely on deep learning, which is flawed since the existing facial databases are insufficient, making it even more inadequate to bypass facial masks. This is why the present research paper suggests implementing the Deep Convolutional Neural Networks (DCNN) algorithm using the Japanese Female Facial Expression (JAFFE) to simulate a masked face emotion recognition. This facial database is available free for academic research, was utilized to label the available images displaying various facial emotions under the umbrella of one of the seven basic human facial emotions, allowing for a more advanced facial technology. Consistent with the latest research findings, the proposed facial emotion recognition attains up to an accuracy of 71.35% due to its meticulous masked facial database. © 2021 IEEE.

[Physiological cost of wearing protective masks - a narrative review of the literature]. / Koszt fizjologiczny noszenia masek ochronnych ­ narracyjny przeglad literatury.

Due to the controversy related to the necessity to wear protective masks and the negative perceptions of users, an attempt was made to analyze the available scientific research on the physiological consequences of wearing various types of masks. The literature review includes publications available in the PubMed bibliographic database, describing symptoms and complaints of mask users (e.g., the feeling of discomfort, fatigue, headaches), different physiological reactions depending on the type of mask (surgical masks, masks with an exhalation valve, with air flow, etc.) as well as the influence of air composition, temperature and humidity in the space under the mask. The impact of using the mask on the ability to exercise (maximal effort, moderate effort) and mental work was outlined. The consequences of wearing masks by people in a different physiological state (pregnancy) were discussed. Proposals for the organization of work were also presented in order to minimize the negative consequences for people wearing masks. The analysis of the presented studies shows that, regardless of the type of masks worn, they can intensify the body's reactions to a varying degree, increasing the physiological cost of work and worsening the ability to make both physical and mental effort. In addition, the mask can contribute, among others, to more frequent headaches, symptoms of fatigue or the subjective feeling of discomfort. However, despite these adverse effects, the use of masks is important to protect people against harmful factors in the work and communal environments, and during the current SARS-CoV-2 pandemic, it has become a necessity. The discomfort of wearing a mask can be reduced by taking appropriate breaks. It should be emphasized that the rhythm of work and breaks in wearing the mask should take into account the individual limitations of the employee. Med Pr. 2021;72(5):569-89.

Mortality of a juvenile Magellanic penguin (Spheniscus magellanicus, Spheniscidae) associated with the ingestion of a PFF-2 protective mask during the Covid-19 pandemic.

We report the discovery of a dead Magellanic penguin (Spheniscus magellanicus) found on Juquehy Beach (23°46'S 45°44'W), municipality of São Sebastião, Brazil, on September 9th 2020. Following necropsy, we noted the presence of an adult size PFF-2 protective mask within the stomach of the penguin which we inferred as the cause of death. As far as we are aware, this is the first recorded instance of marine animal mortality by protective face mask ingestion. Whilst concerns have been raised relating microplastic contamination in marine environments from Covid-19 related waste, there has been relatively less attention paid to the potential risk of macro-scale contaminants, such as protective face coverings. We suggest that Covid-19 related macro contaminants be considered in coastal marine risk assessments and urge further research on this topic.

Effective inactivation of porcine epidemic diarrhea virus on contaminated surgery masks by low-concentrated sodium hypochlorite dispersion.

Coronaviruses present a considerable concern for humans and animals. The current world- wide pandemic of SARS-CoV-2 virus showed many gaps in understanding of coronaviruses spread and transmission. Because of lack of effective vaccine against SARS-CoV-2 the only preventive measures are represented by wearing protective masks and gloves thus limiting potential risk of contact with the airborne virus. Inversely, the limited time of protective function of the masks presents another drawback of their use. Therefore, the application of disinfection agent dispersed on the surface of protective masks may enhance their effectivity and safety of their application. The aim of the study was to examine the virucidal efficacy of low-concentra- ted sodium hypochlorite dispersed using ultrasonic humidifier on the surface of surgery masks. The study was conducted using SARS-CoV-2 surrogate virus, namely porcine epidemic diarrhea virus (PEDV) representing a model with similar biophysical properties and genomic structure to human coronaviruses. Five different concentrations of the disinfectant with different content of sodium hypochlorite were selected for the study. A final concentration of 0.228 g/L sodium hypochlorite effectively inactivated the PED virus and may support the biosafety of masks usage.

Polylactic acid as a suitable material for 3D printing of protective masks in times of COVID-19 pandemic.

A critical lack of personal protective equipment has occurred during the COVID-19 pandemic. Polylactic acid (PLA), a polyester made from renewable natural resources, can be exploited for 3D printing of protective face masks using the Fused Deposition Modelling technique. Since the possible high porosity of this material raised questions regarding its suitability for protection against viruses, we have investigated its microstructure using scanning electron microscopy and aerosol generator and photometer certified as the test system according to the standards EN 143 and EN 149. Moreover, the efficiency of decontaminating PLA surfaces by conventional chemical disinfectants including 96% ethanol, 70% isopropanol, and a commercial disinfectant containing 0.85% sodium hypochlorite has been determined. We confirmed that the structure of PLA protective masks is compact and can be considered a sufficient barrier protection against particles of a size corresponding to microorganisms including viruses. Complete decontamination of PLA surfaces from externally applied Staphylococcus epidermidis, Escherichia coli, Candida albicans and SARS-CoV-2 was achieved using all disinfectants tested, and human adenovirus was completely inactivated by sodium hypochlorite-containing disinfectant. Natural contamination of PLA masks worn by test persons was decontaminated easily and efficiently by ethanol. No disinfectant caused major changes to the PLA surface properties, and the pore size did not change despite severe mechanical damage of the surface. Therefore, PLA may be regarded as a suitable material for 3D printing of protective masks during the current or future pandemic crises.

[Provisioning of personal protective equipment in hospitals in preparation for a pandemic]. / Bevorratung persönlicher Schutzausrüstung in Kliniken zur Vorbereitung auf eine Pandemie.

BACKGROUND: At the beginning of the SARS-CoV­2 outbreak, personal protective equipment (PPE) was scarce worldwide, leading to the treatment of patients partially without sufficient protection for the medical personnel. In order to be prepared for a new epidemic or pandemic or a "second wave" of COVID-19 outbreak and to meet a renewed deficiency of PPE, considerations were made on how personnel and patients can be better protected by appropriate provisioning. OBJECTIVE: The aim of this study was to develop a tool to predict the necessary amount of PPE to be in stock at a transregional university hospital for a certain period of time during a pandemic. MATERIAL AND METHODS: The consumption of PPE needed for every patient was calculated based on the following data of the Ulm University Hospital: the total consumption of healthcare workers' PPE for April 2020 recorded by the materials management department and the number of patients suffering from COVID-19 and their treatment days. From the amount of PPE necessary for every patient in the intensive care unit (ICU) or in an infection ward, a PPE calculator was created in which the estimated amount of PPE can be calculated with the input variables "patients in intensive care unit", "patients in infection ward" and "treatment days". To validate the PPE calculator, the actual consumption of PPE for May 2020 at the Ulm University hospital was compared to the theoretically calculated demand by the PPE calculator. RESULTS: In April 2020 PPE consisting of 18 different items were kept in stock at Ulm University Hospital and in total 1,995,500 individual items were used. 22 intensive care patients with 257 nursing days and in the infection ward 39 patients with 357 nursing days were treated for COVID-19 disease, leading to a total of 603.2 man-days. A total of 34,550 KN95 masks, 1,558,780 gloves and 1100 goggles or protective visors were used, with a daily average of 49 NK95 masks and 2216 gloves required per ICU patient. In May 2020, 6 ICU patients and 19 patients in infection wards were treated for COVID-19 with 34 nursing days in intensive care and 201 nursing days in infection wards. The use of PPE material was 39% lower than in the previous month but in absolute terms 82% and on average 39% higher than calculated. CONCLUSION: The developed tool allows our hospital to estimate the necessary amount of PPE to be kept in stock for future pandemics. By taking local conditions into account this tool can also be helpful for other hospitals.

Layer-By-Layer Nanocoating of Antiviral Polysaccharides on Surfaces to Prevent Coronavirus Infections.

In 2020, the world is being ravaged by the coronavirus, SARS-CoV-2, which causes a severe respiratory disease, Covid-19. Hundreds of thousands of people have succumbed to the disease. Efforts at curing the disease are aimed at finding a vaccine and/or developing antiviral drugs. Despite these efforts, the WHO warned that the virus might never be eradicated. Countries around the world have instated non-pharmaceutical interventions such as social distancing and wearing of masks in public to curb the spreading of the disease. Antiviral polysaccharides provide the ideal opportunity to combat the pathogen via pharmacotherapeutic applications. However, a layer-by-layer nanocoating approach is also envisioned to coat surfaces to which humans are exposed that could harbor pathogenic coronaviruses. By coating masks, clothing, and work surfaces in wet markets among others, these antiviral polysaccharides can ensure passive prevention of the spreading of the virus. It poses a so-called "eradicate-in-place" measure against the virus. Antiviral polysaccharides also provide a green chemistry pathway to virus eradication since these molecules are primarily of biological origin and can be modified by minimal synthetic approaches. They are biocompatible as well as biodegradable. This surface passivation approach could provide a powerful measure against the spreading of coronaviruses.