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This work presents an exhaustive visualization of the airflow expulsed by a person while breathing, talking, exhaling, and blowing inside a closed room wearing a disposable face mask like those used in hospitals for patient protection and those who care for them. An optical schlieren experimental arrangement was used to obtain some of the relevant physical characteristics of the airflow, such as its refractive index gradient, the distribution of temperature, and the associated velocity field for all the tests developed. We tested three face masks, one of the surgical types and the others of the N95 series with denominations KN95 and 3MN95 (Aura TC-84A-8590). The results show appreciable differences between the masks evaluated; the surgical mask was the one that allowed the most abrupt output airflow through it in the field of view of the experimental setup. However, were also found some differences in the performance of the KN95 and 3MN95 masks. The KN95 face mask had the best performance since it expulsed to its surroundings the lowest airflow with different physical properties to the input airflow. The results obtained are relevant since it was possible to estimate the expulsed airflow velocity as a function of the distance for every face mask tested, which allows for understanding its filtering capacity by restricting the flow of potential pathogens from the mouth or nose of one person to another. Undoubtedly, the airflow behavior determination around a face mask can help to reduce the risk of spreading infectious airborne particles.

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INTRODUCTION: To guarantee treatment reproducibility and stability, immobilization devices are essential. Additionally, surface-guided radiation therapy (SGRT) serves as an accurate complement to frameless stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) by aiding patient positioning and real-time monitoring, especially when non-coplanar fields are in use. At our institute, we have developed a surface-guided SRS (SG-SRS) workflow that incorporates our innovative open-face mask (OM) and mouth bite (MB) to guarantee a precise and accurate dose delivery. METHODS: This study included 40 patients, and all patients were divided into closed mask (CM) and open-face mask (OM) groups according to different positioning flow. Cone beam computed tomography (CBCT) scans were performed, and the registration results were recorded before and after the treatment. Then Bland-Altman method was used to analyze the consistency of AlignRT-guided positioning errors and CBCT scanning results in the OM group. The error changes between 31 fractions in one patient were recorded to evaluate the feasibility of monitoring during treatment. RESULTS: The median of translation error between stages of the AlignRT positioning process was (0.03-0.07) cm, and the median of rotation error was (0.20-0.40)°, which were significantly better than those of the Fraxion positioning process (0.09-0.11) cm and (0.60-0.75)°. The mean bias values between the AlignRT guided positioning errors and CBCT were 0.01 cm, - 0.07 cm, 0.03 cm, - 0.30°, - 0.08° and 0.00°. The 31 inter-fractional errors of a single patient monitored by SGRT were within 0.10 cm and 0.50°. CONCLUSIONS: The application of the SGRT with an innovative open-face mask and mouth bite device could achieve precision positioning accuracy and stability, and the accuracy of the AlignRT system exhibits excellent constancy with the CBCT gold standard. The non-coplanar radiation field monitoring can provide reliable support for motion management in fractional treatment.

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The appearance of skin strongly influences people´s self-esteem and well-being. Among the characteristics that affect the most, we can cite acne and wrinkles. Therefore, minimizing those characteristics by using cosmetics has important value for the consumer. Nowadays, there is a demand for natural ingredients, mainly concerning cosmetic products. The use of clays in beauty care is old, with therapeutic uses since Prehistory. There is an essential advantage in using clays for cosmetic purposes, as it is a low-cost, environmentally friendly, natural, and abundant ingredient, which is chemically inert with a low level of toxicity (when in adequate conditions), easy to apply and remove, dries, and hardens fast. In this research work, we aimed at developing and investigating the effect of formulations containing red, green, and black clays as active components in oiliness reduction, and firmness and elasticity improvement in vivo, as well as characterizing clays mineralogically. All clays presented different compositions. Black clay was the one with the simplest mineralogic content, lowest density, and smallest particle size. It was the richest in Si and Al. Green clay presented expandable smectite and the highest density. Red clay presented the largest particle average size and was the richest in iron content. By thermal analysis, clays presented two characteristic events: the water loss (dehydration) and the dihydroxylation of kaolinite, turning into meta kaolinite. In Sebumetry, clays showed a significant reduction of skin oiliness on the forehead in both concentrations after 2h of contact compared to control, baseline, and placebo. However, after 4h (2h after removal), no significant difference was observed with the control. In the Cutometry, clays did not present significant efficacy in skin firmness and elasticity improvement when compared to control and placebo sites, thus, further studies should be performed comparing the efficacy of different vehicles with dispersed clays. Finally, clay mask formulations were developed with black, red, and green clay dispersed in an oil-free gel vehicle, which proved to be adequate for oily skin

A aparência da pele influencia fortemente autoestima e o bem-estar das pessoas. Dentre as características que mais afetam podemos citar acne e rugas. Portanto, minimizar estas características com o uso de cosméticos tem um valor importante para o consumidor. Atualmente existe uma procura por ingredientes naturais, principalmente no que diz respeito a produtos cosméticos. O uso das argilas nos cuidados de beleza é antigo, com usos terapêuticos desde a Pré-História. Há uma vantagem essencial na utilização de argilas para fins cosméticos, pois é um ingrediente de baixo custo, ecologicamente correto, natural, e abundante, que é quimicamente inerte e tem baixo nível de toxicidade (quando usado em condições adequadas), fácil de aplicar e remover, seca, e endurece rapidamente. Neste trabalho de pesquisa, objetivamos desenvolver e investigar o efeito de formulações contendo argilas vermelha, verde e preta como componentes ativos na redução da oleosidade e na melhoria da firmeza e elasticidade in vivo, bem como caracterizar mineralogicamente as argilas. Todas as argilas apresentaram diferentes composições. A argila preta foi a de conteúdo mineralógico mais simples, mais baixa densidade, e menor tamanho de partícula. Foi a mais rica em Si e Al. A argila verde apresentou esmectita expansível e mais alta densidade. A argila vermelha apresentou o maior tamanho médio de partícula e foi a mais rica em ferro. Segundo a análise térmica, as argilas apresentaram dois eventos característicos: a perda de água (desidratação) e a desidroxilação da caulinita, transformando-se em meta-caulinita. Na Sebumetria, as argilas demonstraram significativa redução na oleosidade da pele na testa em ambas as concentrações após 2h de contato comparada ao controle, basal e placebo. Porém, após 4h (2h após remoção), nenhuma diferença significativa foi observada com o controle. Na Cutometria, as argilas não apresentaram Eficácia significativa na melhora da firmeza e elasticidade quando comparadas aos sítios controle e placebo, portanto, mais estudos devem ser realizados comparando a eficácia de diferentes veículos com argilas dispersas. Finalmente, as formulações de máscaras de argilas foram desenvolvidas com argilas preta, vermelha e verde dispersas em um veículo em gel livre de oleosidade, o qual provou ser adequado para pele oleosa

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(1) Background: Mask-associated dry eye (MADE) has been associated with increased dry eye symptoms, apparently due to reduced tear break-up time (TBUT). This study aimed to determine the short-term impact of surgical face mask (FM) on tear film stability by measuring non-invasive tear break-up time (NIBUT). (2) Methods: Twenty-six healthy participants had NIBUT evaluated without FM, with surgical FM and with a surgical FM secured to the skin with adhesive tape (TFM). NIBUT-first was measured with Keratograph 5M (K5M, Oculus, Wetzlar, Germany). Each participant had NIBUT measured in four sessions on four consecutive days. Session 1: without FM vs. with FM. Session 2: with FM vs. without FM. Session 3: without FM vs. with TFM. Session 4: with TFM vs. without FM (3). The time between each measured setting was 2 min. Results: The mean ± SD NIBUT without FM was 8.9 ± 3.7, with FM 10.2 ± 4.1, and with TFM 8.4 ± 3.8 s. No significant differences were observed in NIBUT in any of the evaluated settings: without FM vs. with FM (p = 0.247), without FM vs. with TFM (p = 0.915), and with FM vs. with TFM (p = 0.11). (4) Conclusions: This study did not find a significant short-term effect of FM on NIBUT. Other variables or longer periods of exposure might trigger the symptoms and ocular surface alterations in MADE.

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The world has been greatly affected by the COVID-19 pandemic, causing people to remain isolated and decreasing the interaction between people. Accordingly, various measures have been taken to continue with a new normal way of life, which is why there is a need to implement the use of technologies and systems to decrease the spread of the virus. This research proposes a real-time system to identify the region of the face using preprocessing techniques and then classify the people who are using the mask, through a new convolutional neural network (CNN) model. The approach considers three different classes, assigning a different color to identify the corresponding class: green for persons using the mask correctly, yellow when used incorrectly, and red when people do not have a mask. This study validates that CNN models can be very effective in carrying out these types of tasks, identifying faces, and classifying them according to the class. The real-time system is developed using a Raspberry Pi 4, which can be used for the monitoring and alarm of humans who do not use the mask. This study mainly benefits society by decreasing the spread of the virus between people. The proposed model achieves 99.69% accuracy with the MaskedFace-Net dataset, which is very good when compared to other works in the current literature.

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Background: Face masks are widely used during the COVID-19 pandemic as one of the protective measures against the viral infection risk. Some evidence suggests that face mask prolonged use can be uncomfortable, and discomfort can be exacerbated during exercise. However, the acute responses of mask-wearing during exercise on affective/psychological and exercise performance responses is still a topic of debate. Purpose: To perform a systematic review with meta-analysis of the acute effects of mask-wearing during exercise on affective/psychological and exercise performance responses in healthy adults of different/diverse training status. Methods: This review (CRD42021249569) was performed according to Cochrane's recommendations, with searches performed in electronic (PubMed, Web of Science, Embase, SportDiscus, and PsychInfo) and pre-print databases (MedRxiv, SportRxiv, PsyArXiv, and Preprint.Org). Syntheses of included studies' data were performed, and the RoB-2 tool was used to assess the studies' methodological quality. Assessed outcomes were affective/psychological (discomfort, stress and affective responses, fatigue, anxiety, dyspnea, and perceived exertion) and exercise performance time-to-exhaustion (TTE), maximal power output (POMAX), and muscle force production] parameters. Available data were pooled through meta-analyses. Results: Initially 4,587 studies were identified, 36 clinical trials (all crossover designs) were included. A total of 749 (39% women) healthy adults were evaluated across all studies. The face mask types found were clothing (CM), surgical (SM), FFP2/N95, and exhalation valved FFP2/N95, while the most common exercises were treadmill and cycle ergometer incremental tests, beyond outdoor running, resistance exercises and functional tests. Mask-wearing during exercise lead to increased overall discomfort (SMD: 0.87; 95% CI 0.25-1.5; p = 0.01; I2 = 0%), dyspnea (SMD: 0.40; 95% CI 0.09-0.71; p = 0.01; I2 = 68%), and perceived exertion (SMD: 0.38; 95% CI 0.18-0.58; p < 0.001; I2 = 46%); decreases on the TTE (SMD: -0.29; 95% CI -0.10 to -0.48; p < 0.001; I2 = 0%); without effects on POMAX and walking/running distance traveled (p > 0.05). Conclusion: Face mask wearing during exercise increases discomfort (large effect), dyspnea (moderate effect), and perceived exertion (small effect), and reduces the TTE (small effect), without effects on cycle ergometer POMAX and distance traveled in walking and running functional tests. However, some aspects may be dependent on the face mask type, such as dyspnea and perceived exertion. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021249569], identifier [CRD42021249569].

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INTRODUCTION: COVID-19 superspreader events have occurred when symptomatic individuals without wearing face masks boarded buses. OBJECTIVE: To report the risk of superspreader events when presymptomatic individuals boarded buses to-gether with unvaccinated passengers, but with non-pharmacological preventive interventions being maintained. METHODS: Prospec-tive study of health personnel transported in buses to a COVID-19 vaccination center for two weeks. Open windows, correct use of face masks and exclusion of symptomatic individuals were mandatory. Prospective surveillance identified workers with COVID-19 within 14 days after vaccination. Each asymptomatic passenger of buses where cases were identified was monitored for a similar time period. Voluntary screening results were available for workers who were tested in the month before or after vaccination. RESULTS: 1,879 workers boarded 65 buses. On-board time ranged from three to eight hours. Twenty-nine cases of COVID-19 and four asymptomatic cases were identified among 613 passengers of 21 buses. Median time between vaccina-tion and COVID-19 symptoms onset was six days. One case of suspected transmission on a bus was identi-fied. CONCLUSIONS: Strict nonpharmacological preventive interventions substantially reduced the risk of COVID-19 super-spreader events in buses boarded by presymptomatic individuals.

ANTECEDENTES: Ha ocurrido superpropagación de COVID-19 cuando individuos sintomáticos sin uso de cubrebocas abordaron autobuses. OBJETIVO: Reportar el riesgo de superpropagación cuando individuos presintomáticos abordaron autobuses junto con pasajeros no vacunados pero se mantuvieron intervenciones preventivas no farmacológicas. MATERIAL Y MÉTODOS: Estudio prospec­tivo de personal de salud transportado durante dos semanas en autobuses a un centro de vacunación contra COVID-19. Fue obligatorio llevar ventanas abiertas, uso correcto de cubrebocas y exclusión de personas con síntomas. La vigilancia prospectiva identificó a trabajadores con COVID-19 los 14 días siguientes a la vacunación. Cada pasajero asintomático de autobuses donde se detectaron casos fue vigilado durante un periodo de tiempo similar. Los resultados de tamizaje voluntario estuvieron disponibles para los trabajadores que se realizaron prueba el mes previo o el siguiente a la vacunación. RESULTADOS: 1879 trabajadores abordaron 65 autobuses. El tiempo a bordo varió de tres a ocho horas. Veintinueve casos de COVID-19 y 4 casos asintomáticos fueron identificados entre 613 pasajeros de 21 autobuses. La mediana de tiempo entre la vacunación y el inicio de síntomas en casos de COVID-19 fue de seis días. Fue identificado un caso de transmisión sospechada en autobús. CONCLUSIONES: Las intervenciones preventivas no farmacológicas estrictas redujeron sustancialmente el riesgo de superpropagación de COVID-19 en autobuses ocupados por individuos presintomáticos.

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This project aimed to develop an innovative mask design, aided by 3D printing technology that was able to protect its wearers against virus infection. The project was motivated with the intention of helping to fight Covid-19, but that its use was extensive as an option to N95 and similar masks, already on the market, even after the pandemic. Whose main design objective was that the mask had a sealing efficiency based on a half-face mask and that it could be used in conjunction with masks made of antiviral fabrics, such as, for example, a surgical mask that has its filtering capacity already tested and approved and, which would be the filter element of the mask. The mask was also intended to be reusable so that it could be washed for cleaning, with only the fabric filter element being disposable.

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Not wearing a face mask, despite the sanitary recommendation, represented a public health risk during the COVID-19 pandemic. For this reason, the aim of the study was to determine the mediating role of moral disengagement in the relationship between the dark triad and face mask wearing during the second wave of the pandemic. We worked with a sample made up of 534 adults, who were administered the Dirty Dozen Dark test, the Moral Disengagement Mechanisms Scale and a questionnaire on the frequency of use of face masks. The results showed that moral disengagement mediates the effect of each trait of the dark triad (Machiavellianism, psychopathy and narcissism) on the use of face masks. It is concluded that those who possess any of the dark personality traits morally disengage in order not to use a face mask, exercising a reckless behavior of the possible contagion of COVID-19 to others.

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BACKGROUND: The use of respiratory devices can mitigate the spread of diseases such as COVID-19 in community settings. We aimed to determine the effectiveness of closed face shields with surgical face masks to prevent SARS-CoV-2 transmission in working adults during the COVID-19 pandemic in Bogotá, Colombia. METHODS: An open-label non-inferiority randomized controlled trial that randomly assigned participants to one of two groups: the intervention group was instructed to wear closed face shields with surgical face masks, and the active control group was instructed to wear only surgical face masks. The primary outcome was a positive reverse transcription polymerase chain reaction test, IgG/IgM antibody test for SARS-CoV-2 detection, or both during and at the end of the follow-up period of 21 days. The non-inferiority limit was established at - 5%. RESULTS: A total of 316 participants were randomized, 160 participants were assigned to the intervention group and 156 to the active control group. In total, 141 (88.1%) participants in the intervention group and 142 (91.0%) in the active control group completed the follow-up. PRIMARY OUTCOME: a positive SARS-CoV-2 test result was identified in one (0.71%) participant in the intervention group and three (2.1%) in the active control group. In the intention-to-treat analysis, the absolute risk difference was - 1.40% (95% CI [- 4.14%, 1.33%]), and in the per-protocol analysis, the risk difference was - 1.40% (95% CI [- 4.20, 1.40]), indicating non-inferiority of the closed face shield plus face mask (did not cross the non-inferiority limit). CONCLUSIONS: The use of closed face shields and surgical face masks was non-inferior to the surgical face mask alone in the prevention of SARS-CoV-2 infection in highly exposed groups. Settings with highly active viral transmission and conditions such as poor ventilation, crowding, and high mobility due to occupation may benefit from the combined use of masks and closed face shields to mitigate SARS-CoV-2 transmission. TRIAL REGISTRATION: ClinicalTrials.gov NCT04647305 . Registered on November 30, 2020.

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