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Changes of microbial growth during use of face masks from different materials
Korvasová, Lucie ; Hoová, Julie (referee) ; Márová, Ivana (advisor)
Due to the current spread of Covid-19 disease, there are many types of respiratory protective equipment on the Czech market. However, due to the conditions that breath creates on the inside of the masks, they can be an ideal place for multiplication of microorganisms such as yeasts, moulds and especially bacteria. Since various protection masks differ in their production materials, bacteria colonization won’t always be the same. The subject of the thesis is a comparison of individual types of masks and respirators with regard to multiplication of microorganisms in their structure, which were tested using the contact stamp-form method on agar plates and in a liquid medium. Sterile environment was required during the work to avoid external contamination. Methods of imprinting on agar plates and the fact that turbidity and thus measurable absorbance increases with rising number of microorganisms were used to obtain the data. Result of the work was that face masks already contained some level of contamination from their production. As the best kind of face masks in terms of multiplication of microorganisms came out cotton, which prevented multiplying in the inoculated sphere. At the same time each growing culture was tested for viability, where it was determined how many viable cells each sample contained in comparison to a fully grown culture.
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Modeling of Respiratory System
Matoušek, Josef ; Roleček, Jiří (referee) ; Jiřík, Radovan (advisor)
This thesis is concerned with respiration system simulation. The main goal of this studies is to gain knowledge of how human respiration system works, along with selecting proper algorithms and their implementation into mathematic model. These models are realized by Simulink interface, which is part of Matlab environment. Similar models are used for medical technology research, especially for artificial ventilation of the lungs. There is a practical utilisation of these models suitable for illustration and respiration system's biological processes simulation, particularly combined model described in GUIDE graphic interface - also implemented in Matlab environment.
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Face masks and respirators as protection against viruses and bacteria
Varga, Michal ; Mišík, Ondrej (referee) ; Lízal, František (advisor)
Pandemic caused by virus SARS-CoV-2 brought high attention to face masks and raised some questions about their filtration efficiency and performance affecting parameters such as high humidity, long term usage, fit factor, or possible decontamination methods for usage prolonging. In this thesis, mechanisms of SARS-CoV-2 transmission and structure and materials of face masks are firstly discussed. Then mechanisms of particle deposition on filter fibers are described. Subsequently standards of surgical masks, cloth masks and respirators are described and compared, with detail on carbon dioxide concentration under respirator. Nanoparticles and their possible effects on enhancing face mask parameters are briefly characterized. Then filtration efficiency and affecting parameters are evaluated. And finally possible decontamination methods for face masks reusability are summarized.
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Changes of microbial growth during use of face masks from different materials
Korvasová, Lucie ; Hoová, Julie (referee) ; Márová, Ivana (advisor)
Due to the current spread of Covid-19 disease, there are many types of respiratory protective equipment on the Czech market. However, due to the conditions that breath creates on the inside of the masks, they can be an ideal place for multiplication of microorganisms such as yeasts, moulds and especially bacteria. Since various protection masks differ in their production materials, bacteria colonization won’t always be the same. The subject of the thesis is a comparison of individual types of masks and respirators with regard to multiplication of microorganisms in their structure, which were tested using the contact stamp-form method on agar plates and in a liquid medium. Sterile environment was required during the work to avoid external contamination. Methods of imprinting on agar plates and the fact that turbidity and thus measurable absorbance increases with rising number of microorganisms were used to obtain the data. Result of the work was that face masks already contained some level of contamination from their production. As the best kind of face masks in terms of multiplication of microorganisms came out cotton, which prevented multiplying in the inoculated sphere. At the same time each growing culture was tested for viability, where it was determined how many viable cells each sample contained in comparison to a fully grown culture.
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Face masks and respirators as protection against viruses and bacteria
Varga, Michal ; Mišík, Ondrej (referee) ; Lízal, František (advisor)
Pandemic caused by virus SARS-CoV-2 brought high attention to face masks and raised some questions about their filtration efficiency and performance affecting parameters such as high humidity, long term usage, fit factor, or possible decontamination methods for usage prolonging. In this thesis, mechanisms of SARS-CoV-2 transmission and structure and materials of face masks are firstly discussed. Then mechanisms of particle deposition on filter fibers are described. Subsequently standards of surgical masks, cloth masks and respirators are described and compared, with detail on carbon dioxide concentration under respirator. Nanoparticles and their possible effects on enhancing face mask parameters are briefly characterized. Then filtration efficiency and affecting parameters are evaluated. And finally possible decontamination methods for face masks reusability are summarized.
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Modeling of Respiratory System
Matoušek, Josef ; Roleček, Jiří (referee) ; Jiřík, Radovan (advisor)
This thesis is concerned with respiration system simulation. The main goal of this studies is to gain knowledge of how human respiration system works, along with selecting proper algorithms and their implementation into mathematic model. These models are realized by Simulink interface, which is part of Matlab environment. Similar models are used for medical technology research, especially for artificial ventilation of the lungs. There is a practical utilisation of these models suitable for illustration and respiration system's biological processes simulation, particularly combined model described in GUIDE graphic interface - also implemented in Matlab environment.
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Penetration Through CE-Marked Respirators - Cut-Based Versus Manikun-Based Method
Ondráček, Jakub ; Serfozo, N. ; Zíková, Naděžda
This work presents size-resolved penetration testing of 13 commercially available filtering facepieces (FFP1, FFP2 and FFP3 filtering classes) on pieces of filtration material (47 mm in diameter) cut from various FFRs (referred as cut-based). Second objective of this work was to measure the size-resolved penetration of 9 complete FFRs (selected from identical filtering facepieces as in the first case) placed on the manikin (refered as manikin-based). The results obtained by these two methods were compared and the real MPPS of all FFRs obtained by both methods were estimated.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22015102910290 - PDF
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Penetration of Commercial Filter Materials in Detailed Study
Ondráček, Jakub ; Zíková, Naděžda ; Ždímal, Vladimír
Testing of various filter materials proved the functionality, good precision and reproducibility of a home-made filter tester. The measurements of penetration for standard commercial filter materials might be useful for many scientists and other users working with these materials. The comparison of penetration for different types of filtration materials showed wide variety of penetration curves, MPPS and the maximum penetration. This study also confirmed our initial doubts about the standard filter efficiency testing method, regarding the used testing material, setting of MPPS and measuring only the total penetration of a polydisperse aerosol. Therefore, such a study could serve also as a basis for improvements in the filter efficiency standard method, which seems to give insufficient and in some perspectives limited or even misleading information.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22012102615351 - PDF
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