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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Studium konzervačních systémů pro kosmetiku / Study of preservative systems for cosmetics

Šmétková, Zuzana January 2009 (has links)
The aim of this diploma thesis was to prove the antimicrobial actvivity of the selected syntetic preservatives used in cosmetics, such as methylparaben, butylparaben, phenoxyethanol, bronopol, imidazolidinyl urea and methylisothaizolinone, in different concentrations (up to the highest permitted concentration and in increased concentrations), and of some essential oils, which are possible to use in cosmetics (essential oil from Eucalyptus globulus, Pimpinella anisum, Lavandula officinalis, Rosmarinus officinalis, Foeniculum vulgare, Mentha piperita, Juniperus communis and Pinus sylvestris). The effect was investigated in every preservative system alone, in order to evaluate the spectrum and the rate of each one. As indicator microorganism was chosen Bacillus subtilis and Penicillium chrysogenum. The used methods was disk difusion method and modify difusion method. From synthetic preservatives had the best effects bronopol, imidazolidinyl urea and methylisothiazolinone. From chosen natural antimicrobails had the effect against both indicator microorganisms the Mentha piperita, Foeniculum vulgare and Juniperus communis extracts.
32

Analýza vybraných alergenů ve vonných kompozicích / Analysis of selected allergens in fragrances

Koláčková, Adéla January 2010 (has links)
This thesis is focused on potentially allergenic substances (PASs) in cosmetics. Their specific features, methods of control and observation are described. There are also mentioned dermatology problems connected with usage of perfumed cosmetic products in which the allergenic ingredients can be found and possibilities of their regulation. Fragrances are mixtures of natural or synthetic character which give the aroma. In nature, fragrances are produced mainly by plants. More than one hundred fragrances have been identified as allergens. Twenty six of them were declared as PASs. Allergenic components of perfume compositions are the main cause of allergic contact dermatitis. Experimental part of the thesis is focused on the procedure of analysis of specific allergenic fragrances (?-Amylcinnamaldehyde, Anisealcohol, Benzylsalicylate, Cinnamaldehyde, ?-Hexylcinnamaldehyde, 7-Hydroxycitronellal and Methyl-2-octynoate). Headspace-Solid Phase Microextraction connected with Gas Chromatography-Flame Ionisation Detector (HS-SPME-GC-FID) was used for extraction, analysis and identification of these substances. The method was validated and applied on the spectrum of real samples of cosmetic products.
33

Příprava enkapsulovaných enzymů pro využití v kosmetice / Preparation of encapsulated enzymes for cosmetics application

Bokrová, Jitka January 2014 (has links)
Presented diploma thesis is focused on testing of an appropriate form of encapsulated enzymes intended for application in cosmetic and pharmaceutical industry. For encapsulation, proteolytic enzymes bromelain, papain and collagenase were used. These enzymes were encapsulated into alginate and chitosan microparticles prepared by an encapsulator and packed into liposomes. Encapsulation effectiveness was evaluated by analysis of total proteins. Particles stability was evaluated in model and real conditions by photometrical analysis of released proteins. Proteolytic activity of released enzymes in model and real conditions were observed too. Alginate and chitosan microparticles prepared by the encapsulator were found as an appropriate form of encapsulated enzymes designed to wound healing. Encapsulation effectiveness of these particles and stability in model conditions were good in comparison with liposomes. Hydrogel and water-oil emulsion were used for analysis of particles stability at real conditions. Hydrogel was found as a good option for preservation of particles as well as proteolytic enzyme activity. Emulsion made particles less stable and proteolytic activity of enzymes decreased rapidly. Encapsulation enables long-term stabilization of biologically active compounds as well as possibility of targeted transport and controlled releasing. Presented diploma thesis suggests possibilities of application encapsulated enzymes in designing more effective formulations for wound healing.
34

Stanovení vybraných vonných látek v potravinách a kosmetických výrobcích / Assessment of chosen aroma compounds in foods and cosmetics

Obrdlíková, Blanka January 2014 (has links)
This diploma thesis is focused on the problematic of assessment of allergenic aroma compounds in various matrices. In the frame of European legislation 26 of potentially allergenic compounds are stated, whose content in cosmetic products is limited. In the case of foods there is not such restriction so far. In the experimental part, the allergenic aroma compounds in chosen samples of cosmetic and food samples were identified and quantified using Solid phase microextraction in conjunction with gas chromatography. Sensory evaluation of aroma or taste is also included.
35

Analýza trhu s produkty biokosmetiky v regionu Brno-město

Škorpíková, Sandra January 2019 (has links)
The diploma thesis briefly characterizes the main principles of bio-production, defines the term organic cosmetics and its current state on the market, and general trends of cosmetic product sales. Then it characterizes basic marketing terms and defines the issue of consumer buying behaviour. The practical part deals with the analysis of Czech manufacturers of certified cosmetics and their assortment and the availability of this range in specialized stores in the Brnocity region Investigation of possibilities and the use of marketing mix was carried out on a selected retailer of natural and organic cosmetic. In the last survey, attitudes and buying behaviour in relation to natural and organic cosmetics products were found in the form of a questionnaire survey.
36

Stability testing of all-trans-retinol in an experimental cosmetic formulation and in methanol and methanol containing butylhydroxytoluene (BHT) using reversed-phase HPLC / Stabilitetstester av all-trans-retinol i en experimentell kosmetisk formulering och i metanol och metanol innehållande butylhydroxytoluen (BHT) med reversed-phase HPLC

Iglebaek Herceglija, Ena January 2021 (has links)
All-trans-retinol (vitamin A) används ofta som en aktiv ingrediens i kosmetiska produkter på grund av dess kliniskt validerade anti-age-egenskaper. Däremot är användningen av all-trans-retinol i kosmetiska formuleringar begränsad till följd av den kemiska stabiliteten av all-trans-retinol som påverkas av värme, syre, ljus och syror. Både kompositionen av en kosmetisk formulering, samt lagringsförhållanden och förpackningen av produkten, kan påverka nedbrytningen av all-trans-retinol till mindre aktiva former.  I denna studie har stabilitetstestning genomförts under två månader i syfte att utvärdera inverkan som lagringstemperatur (21°C och 5°C) och produktförpackning (en luftfri behållare och en burk) kan ha på nedbrytningen av all-trans-retinol i en experimentell oljegel. All-trans-retinol extraherades med metanol innehållande 0.5 mg/mL butylhydroxytoluen (BHT) och analyserades med reversed-phase HPLC med 1% ammoniumacetat och metanol (12:88, v/v) som mobilfas. I HPLC-kromatogrammen upptäcktes en okänd nedbrytningsprodukt, vilket möjliggjorde stabilitetstestning av all-trans¬-retinol genom att undersöka förändringar i förhållandet mellan nedbrytningsprodukten och all-trans-retinol. Stabilitetstestningen av de experimentella oljegelerna resulterade i mindre än 4% nedbrytningsprodukt i förhållande till mängden all-trans-retinol efter 56 dagars lagring, oberoende av produktförpackning och lagringstemperatur, med den förslagna analysmetoden. Studien visade också att instabiliteten hos extraherad all-trans-retinol har en dominerande inverkan på resultaten som kan leda till en överskattning av nedbrytningsprodukten på grund av temperaturen under beredning och lagring av förberedda prover. Dessutom utvärderades stabiliteten av all-trans-retinol i metanol och metanol innehållande 0,5 mg/ml butylhydroxytoluen (BHT). Upp till 6% nedbrytning av all-trans-retinol i metanol med BHT kan förväntas om beredda proverna lagras i rumstemperatur, medan mindre än 1% nedbrytningsprodukt detekterades i prover som bevaras kylda under analysen. Av denna anledning har det föreslagits att förhållandena vid beredning, hantering och lagring av extraherad all-trans-retinol bör kontrolleras för att förhindra inverkan från omgivningen, såsom temperatur, ljus och syre. / All-trans-retinol, or vitamin A, is frequently used as an active ingredient in cosmetic products because of its clinically validated anti-aging properties. The use of all-trans-retinol in cosmetic formulations is limited by its susceptibility to heat, oxygen, light, and acids. In a cosmetic product, the composition, as well as the storage conditions and the type of packaging, may influence the degradation of all-trans-retinol into less active forms.  In this study, long-term stability testing was conducted with the purpose to evaluate the effect that storage temperature (21°C and 5°C) and product packaging (an airless container and a jar) may have on the degradation of all-trans-retinol in an experimental oil-gel during a 2-months period. All-trans-retinol was extracted with methanol containing 0.5 mg/mL butylhydroxytoluene (BHT) and was analysed with a reversed-phase HPLC system, using 1% ammonium acetate and methanol (12:88) as the solvent system. The HPLC chromatograms revealed an unknown degradation product, allowing stability testing of all-trans-retinol by detecting variations in the ratio between the degradation product and all-trans-retinol. The stability testing of the experimental oil-gels resulted in less than 4% degradation product in relation to all-trans-retinol after 56 days of storage, independent of the product packaging and storage temperature, with the proposed analytical method. It was also shown that the instability of extracted all-trans-retinol will have a predominant impact on the results causing an overestimation of the degradation product because of the temperature during sample preparation and storage. In addition, the stability of all-trans-retinol in methanol and methanol containing 0.5 mg/mL butylhydroxytoluene (BHT) was evaluated. It was concluded that up to 6% degradation of all-trans-retinol in methanol with BHT can be expected if prepared samples are stored in room temperature, while less than 1% degradation product will be present if prepared samples are kept cold during analysis. It has been proposed that the conditions during preparation, handling, and storage of extracted all-trans-retinol should be controlled to prevent interference of external conditions, such as temperature, light, and oxygen.
37

The emerging market of cosmetics for men - What are the adoption barriers? / The emerging market of cosmetics for men: An investigation of consumer behavior in Czech republic

Orlichová, Zuzana January 2011 (has links)
The aim of this study is to describe adoption barriers emerging on the cosmetics for men market through market research and consumer behaviour exploration. The relationship men have with the cosmetics is not easy to understand, so the purpose of this study is to explore on what is based their relationship to cosmetics market - why some are ready to use cosmetics while other reject. Regarding market of cosmetics for men, there are the barriers that prevent in adoption of cosmetics. The thesis would reveal what influence the social decision making, and would go deeper into what influence men; and what the relationships with products, brands, services, and environment they have. The conclusion will be the interpretation of the adoption barriers on cosmetics for men market.
38

Pharmaceutical applications of PheroidTM technology / Anne F. Grobler

Grobler, Anne Frederica January 2009 (has links)
For a drug to have a therapeutic effect, it has to reach its site of action in sufficient quantities. The Pheroid drug delivery system enhances the absorption of drugs in various pharmacological categories and is the focus of this study. A number of patents are registered in various countries to protect its application. Pheroid technology is trademarked, but may for ease of reading, be called Pheroid(s) only. The Pheroid itself is composed of an organic carbon backbone composed of unsaturated fatty acids with some side-chain interactions that result in self-emulsifying characteristics. The resulting vesicles and nano-sponges can entrap hydrophilic, hydrophobic or amphiphilic compounds for biomedical and agricultural application and can be manipulated as to loading ability, mechanical resistance, permeability, size and solubility. Pheroid was investigated for its potential use in the areas of vaccines, peptide drugs, topical products and cosmeceuticals, antimicrobial treatments and agriculture. In all of these areas, the Pheroid has indeed shown applicability: the results showed improved uptake and/or efficacy of the entrapped chemical or biological compounds after administration by a number of administration routes. For oral administration, a precursor format, the pro-Pheroid, was used, wherein the vesicles and/or sponges are formed post-administration. Proof of concept studies on the in vivo absorption and bioavailability, as well as studies on in vitro efficacy of Pheroid-based formulations were carried out for antimicrobials, such as tuberculosis drugs, antimalarials and antiretrovirals. In all cases, the in vitro efficacy of the active compounds was increased, compared to well-known standard drug treatments. In a phase I bio-equivalence study, a Pheroid-containing combination formulation was compared against the comparative market leader. The results demonstrated that the bioavailability of the active compounds in the Pheroid was at least as good but mostly significantly better than that of the comparative medication. In addition, the incidence of side-effects was decreased in the case of the Pheroid formulations. Furthermore, in vitro results indicate that drug resistance can at least partially be negated. Pheroid technology may also be capable of protecting labile drugs such as peptides against degradation and increasing efficacy so that lower dosages can be administered less frequently and with fewer side effects. Based on in vitro and in vivo results, a number of products are currently in development. The application of Pheroid technology is potentially limitless and includes such areas as TB, malaria, cancer, AIDS, gene delivery, vaccines, patented medicines and generics and agriculture. / Thesis (Ph.D. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.
39

Pharmaceutical applications of PheroidTM technology / Anne F. Grobler

Grobler, Anne Frederica January 2009 (has links)
For a drug to have a therapeutic effect, it has to reach its site of action in sufficient quantities. The Pheroid drug delivery system enhances the absorption of drugs in various pharmacological categories and is the focus of this study. A number of patents are registered in various countries to protect its application. Pheroid technology is trademarked, but may for ease of reading, be called Pheroid(s) only. The Pheroid itself is composed of an organic carbon backbone composed of unsaturated fatty acids with some side-chain interactions that result in self-emulsifying characteristics. The resulting vesicles and nano-sponges can entrap hydrophilic, hydrophobic or amphiphilic compounds for biomedical and agricultural application and can be manipulated as to loading ability, mechanical resistance, permeability, size and solubility. Pheroid was investigated for its potential use in the areas of vaccines, peptide drugs, topical products and cosmeceuticals, antimicrobial treatments and agriculture. In all of these areas, the Pheroid has indeed shown applicability: the results showed improved uptake and/or efficacy of the entrapped chemical or biological compounds after administration by a number of administration routes. For oral administration, a precursor format, the pro-Pheroid, was used, wherein the vesicles and/or sponges are formed post-administration. Proof of concept studies on the in vivo absorption and bioavailability, as well as studies on in vitro efficacy of Pheroid-based formulations were carried out for antimicrobials, such as tuberculosis drugs, antimalarials and antiretrovirals. In all cases, the in vitro efficacy of the active compounds was increased, compared to well-known standard drug treatments. In a phase I bio-equivalence study, a Pheroid-containing combination formulation was compared against the comparative market leader. The results demonstrated that the bioavailability of the active compounds in the Pheroid was at least as good but mostly significantly better than that of the comparative medication. In addition, the incidence of side-effects was decreased in the case of the Pheroid formulations. Furthermore, in vitro results indicate that drug resistance can at least partially be negated. Pheroid technology may also be capable of protecting labile drugs such as peptides against degradation and increasing efficacy so that lower dosages can be administered less frequently and with fewer side effects. Based on in vitro and in vivo results, a number of products are currently in development. The application of Pheroid technology is potentially limitless and includes such areas as TB, malaria, cancer, AIDS, gene delivery, vaccines, patented medicines and generics and agriculture. / Thesis (Ph.D. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.
40

”Nothing like myself” : Om kosmetikan och utsmyckningens förhållande till ålder, klass och genus i ungdomsdystopin

Larsson, Jennie January 2014 (has links)
I den här uppsatsen har jag gjort en tematisk läsning av de dystopiska ungdomstrilogierna Hungerspelstrilogin, Divergenttrilogin och Legendtrilogin, vilket jag har gjort med fokus på temat kosmetika och utsmyckning. Syftet var att undersöka de genusmönster som existerar kring kosmetikan och utsmyckningen, liksom dess förhållande till klass och ålder. Jag kommer i uppsatsen fram till att kosmetika och utsmyckning bärs frivilligt av överklass och onda karaktärer och att det tvingas på de flickor, och i viss mån även de pojkar, som är böckernas huvudpersoner. Böckerna tycks bekräfta åsikten att kosmetikan är något förkastligt och påtvingat av patriarkatet. Tvånget kommer dock i böckerna inte enbart ifrån patriarkatet utan också från överklassen. Uppdelningen mellan vad som är okej för flickor och pojkar att bära ser i stort sett likadan ut som i dagens samhälle, trots framtidsskildringens möjligheter att måla upp något nytt. De som frivilligt bär kosmetika och utsmyckning är oftast farliga, såsom onda ledare eller förtryckande överklass. Det feminina nedvärderas i böckerna mer än det könsneutrala (även om kritik kring det neutrala också förekommer) och det kvinnliga nedvärderas starkare än det flickiga. Även om flickorna finner att dekorationen kan vara användbar har den litet eller inget värde då den inte fyller en annan funktion än skönhet. Resultatet blir destruktivt då flickor och kvinnor vänds mot varandra och sig själva. Dessutom blir ramen för vad som är okej snävare då de både ska vara vackra, men inte bry sig om det. Det bekräftar också de genusmönster och förväntningar som säger att flickan ska vara passiv och vacker.

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