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The determination of minimal countercurrent distance of the water surface sensor from the thin-plate V-notch weir.
Kopečná, Monika ; Zubík, Pavel (referee) ; Žoužela, Michal (advisor)
This thesis clarifies the issue of the measuring flows with the help of capacity measurement systems using Q/h characteristics and also describes measuring techniques for determining the water surface level. The various types of measuring weirs and their Q/h characteristics are described in detail. It also mentions the position of the installation of the sensor. The main task is to find a practical minimal countercurrent distance of the water surface sensors used in practice for use with a V-notch weir in the form of experimental measurements in the water management research laboratory at the Department of Water Structures Faculty of Civil Engineering in Brno. The weirs used for this experiment had top angle cutouts of 90°, 53°8´ and 28°4´. The obtained data is evaluated and subsequently the minimal countercurrent distance of the water surface sensor is determined. The thesis also includes recommendations for further research.
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Synthesis and evaluation of transdermal drug permeation enhancers
Kopečná, Monika ; Vávrová, Kateřina (advisor) ; Doležal, Pavel (referee) ; Hampl, František (referee)
Penetration enhancers are compounds that facilitate transdermal drug delivery, which is an advantageous pathway of drug administration (compared to conventional methods). However, skin acts as formidable barrier enabling terrestrial life by protecting the inner body from the environmental conditions, microbes and substances. Thus, for drug administration via this pathway, some approach to temporary increase the skin permeability (e.g. permeation enhancer) should be employed. Despite the existence of many enhancer classes, there is still a need for new compounds enhancing broader spectrum of drugs, with reversible mode of action and better safety profile. One of the promising approaches is to explore natural compounds with low toxicity and irritation potential. In this thesis, I first studied various glucose and galactose derivatives bearing structural fragments that were responsible for enhancing activity of previously studied enhancers (e.g. amino acid derivatives, fatty acids and alcohols, modified ceramides). A detailed examination of these sugar- based compounds revealed potent glucoside and galactoside enhancers (12Glc6N and A15) comparable to or better than Span 20 with reversible mode of action and acceptable toxicity on keratinocyte and fibroblast cell lines. Another part of my work builds...
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Synthesis and evaluation of transdermal permeation enhancers based on terpenes
Kopečná, Monika ; Vávrová, Kateřina (advisor) ; Hrabálek, Alexandr (referee)
Monika Kopečná Synthesis and evaluation of transdermal permeation enhancers based on terpenes Transdermal drug delivery has many advantages over the conventional routes of administration. It could make a treatment of some diseases more acceptable for patients. Other advantage is a possibility of easy interruption of treatment in case of problems. And profit comes also from the fact that the drug doesn't pass through the gastro-intestinal tract, so it avoids the first-pass effect and doesn't irritate this tract, too. But majority of drugs cannot cross the skin in sufficient amounts. To enable permeation of more drugs through the human skin, substances called transdermal permeation enhancers are used among others, some natural terpenes and amino acid derivatives such as dodecylester of 6-(dimethylamino)hexanoic acid (DDAK) are potent permeation enhancers (1) (2). The purpose of my work was to combine these potent enhancers and prepare esters of 6-(dimethylamino)hexanoic acid with selected terpenes (menthol, citronellol, linalool, farnesol and borneol) and determine their permeation-enhancing activity in vitro using two model drugs (theophylline and hydrocortisone), human skin and Franz diffusion cell. DDAK was able to increase skin flux of theophylline and hydrocortisone 23 and 37 times,...
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Synthesis and evaluation of transdermal drug permeation enhancers
Kopečná, Monika ; Vávrová, Kateřina (advisor) ; Doležal, Pavel (referee) ; Hampl, František (referee)
Penetration enhancers are compounds that facilitate transdermal drug delivery, which is an advantageous pathway of drug administration (compared to conventional methods). However, skin acts as formidable barrier enabling terrestrial life by protecting the inner body from the environmental conditions, microbes and substances. Thus, for drug administration via this pathway, some approach to temporary increase the skin permeability (e.g. permeation enhancer) should be employed. Despite the existence of many enhancer classes, there is still a need for new compounds enhancing broader spectrum of drugs, with reversible mode of action and better safety profile. One of the promising approaches is to explore natural compounds with low toxicity and irritation potential. In this thesis, I first studied various glucose and galactose derivatives bearing structural fragments that were responsible for enhancing activity of previously studied enhancers (e.g. amino acid derivatives, fatty acids and alcohols, modified ceramides). A detailed examination of these sugar- based compounds revealed potent glucoside and galactoside enhancers (12Glc6N and A15) comparable to or better than Span 20 with reversible mode of action and acceptable toxicity on keratinocyte and fibroblast cell lines. Another part of my work builds...
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Synthesis and evaluation of transdermal drug permeation enhancers
Kopečná, Monika ; Vávrová, Kateřina (advisor) ; Doležal, Pavel (referee) ; Hampl, František (referee)
Penetration enhancers are compounds that facilitate transdermal drug delivery, which is an advantageous pathway of drug administration (compared to conventional methods). However, skin acts as formidable barrier enabling terrestrial life by protecting the inner body from the environmental conditions, microbes and substances. Thus, for drug administration via this pathway, some approach to temporary increase the skin permeability (e.g. permeation enhancer) should be employed. Despite the existence of many enhancer classes, there is still a need for new compounds enhancing broader spectrum of drugs, with reversible mode of action and better safety profile. One of the promising approaches is to explore natural compounds with low toxicity and irritation potential. In this thesis, I first studied various glucose and galactose derivatives bearing structural fragments that were responsible for enhancing activity of previously studied enhancers (e.g. amino acid derivatives, fatty acids and alcohols, modified ceramides). A detailed examination of these sugar- based compounds revealed potent glucoside and galactoside enhancers (12Glc6N and A15) comparable to or better than Span 20 with reversible mode of action and acceptable toxicity on keratinocyte and fibroblast cell lines. Another part of my work builds...
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Synthesis and evaluation of transdermal permeation enhancers based on terpenes
Kopečná, Monika ; Vávrová, Kateřina (advisor) ; Hrabálek, Alexandr (referee)
Monika Kopečná Synthesis and evaluation of transdermal permeation enhancers based on terpenes Transdermal drug delivery has many advantages over the conventional routes of administration. It could make a treatment of some diseases more acceptable for patients. Other advantage is a possibility of easy interruption of treatment in case of problems. And profit comes also from the fact that the drug doesn't pass through the gastro-intestinal tract, so it avoids the first-pass effect and doesn't irritate this tract, too. But majority of drugs cannot cross the skin in sufficient amounts. To enable permeation of more drugs through the human skin, substances called transdermal permeation enhancers are used among others, some natural terpenes and amino acid derivatives such as dodecylester of 6-(dimethylamino)hexanoic acid (DDAK) are potent permeation enhancers (1) (2). The purpose of my work was to combine these potent enhancers and prepare esters of 6-(dimethylamino)hexanoic acid with selected terpenes (menthol, citronellol, linalool, farnesol and borneol) and determine their permeation-enhancing activity in vitro using two model drugs (theophylline and hydrocortisone), human skin and Franz diffusion cell. DDAK was able to increase skin flux of theophylline and hydrocortisone 23 and 37 times,...
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The determination of countercurrent process of water surface level decrease before the thin-plate V-notch weirs
Kopečná, Monika ; Šafář,, Robert (referee) ; Žoužela, Michal (advisor)
This diploma thesis deals with finding the minimal countercurrent distance of the water surface sensors used in practice for use with a V-notch weir. The thesis complements the previously obtained results of measurements in the longitudinal vertical plane of symmetry of the inlet channel with measurements on the whole countercurrently located plane of the inlet channel. The measurements are obtained experimentally in the water management research laboratory at the Department of the Water Structures Faculty of Civil Engineering in Brno. Measurements on each individual weir with top angle cutouts of 90°, 53°8´ and 28°4´ are taken at five possible positions of the sensor towards the plane of the measuring weir. All measurements are also repeated for three different vertical distances between the lowest level of the spillway edge and the bottom of the inlet channel. The obtained data are evaluated and subsequently the minimal distances for the location of the water surface sensor in front of a counter weir is determined. The thesis also includes recommendations for practical application presented in the form of text, tables and also graphically.
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The determination of minimal countercurrent distance of the water surface sensor from the thin-plate V-notch weir.
Kopečná, Monika ; Zubík, Pavel (referee) ; Žoužela, Michal (advisor)
This thesis clarifies the issue of the measuring flows with the help of capacity measurement systems using Q/h characteristics and also describes measuring techniques for determining the water surface level. The various types of measuring weirs and their Q/h characteristics are described in detail. It also mentions the position of the installation of the sensor. The main task is to find a practical minimal countercurrent distance of the water surface sensors used in practice for use with a V-notch weir in the form of experimental measurements in the water management research laboratory at the Department of Water Structures Faculty of Civil Engineering in Brno. The weirs used for this experiment had top angle cutouts of 90°, 53°8´ and 28°4´. The obtained data is evaluated and subsequently the minimal countercurrent distance of the water surface sensor is determined. The thesis also includes recommendations for further research.
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