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Synthesis of selaginpulvilin X.
Havlíková, Tereza ; Rýček, Lukáš (advisor) ; Nečas, David (referee)
4 Abstract This bachelor work aims to synthesize the natural product selaginpulvilin X using a six-step synthetic route. Subsequently, the spectra of the synthesized compound were compared with the spectra of the previously isolated compound from the genus Selaginella to verify the proposed structure of selaginpulvilin X. The total synthesis of natural product deploys Suzuki and Sonogashira coupling, generation, and addition of an organolithium compound to aldehyde, consecutive oxidation, and final deprotection. Various protective groups are also used in the preparation of selaginpulvilin X derivatives. Keywords: Natural product, total synthesis, genus Selaginella, Selaginellaceae polyphenols, selaginpulvilin X, Suzuki-Miyaura coupling, Sonogashira coupling
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The importance of vitamin C in nutrition and its effect on cancer prevention.
Havlíková, Tereza ; Martínková, Stanislava (advisor) ; Balínová, Pavla (referee)
The bachelor thesis deals with vitamin C and its importance in human nutrition and cancer prevention. The dissertation is divided into a theoretical and a practical part. The theoretical part begins with a brief introduction to vitamins and their functions, and then the thesis focuses exclusively on vitamin C. General information about vitamin C is described, such as its chemical composition, functions, sources in the diet, recommended daily doses, and then the thesis deals with its role in cancer prevention, discussing the individual functions of vitamin C that affect prevention. The theoretical part concludes with the latest findings and hypotheses from studies and research on vitamin C in oncology. The practical part focuses on the evaluation of a questionnaire survey in which 194 respondents of different ages and educational backgrounds participated. The questionnaire consisted of 18 questions focusing on both the respondents' knowledge and their vitamin C habits. The results indicate that the awareness of both lay and expert respondents is quite high. In conclusion, it was recommended that further questionnaires be carried out with greater attention to equal representation of the groups surveyed. Keywords: vitamin C, prevention, oncology
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Development of ceramic filter equipment for electro-insulating liquids
Havlíková, Tereza ; Cihlář, Jaroslav (referee) ; Maca, Karel (advisor)
Cílem této diplomové práce byla příprava makroporézních keramických filtrů na bázi mullitu a oxidu křemičitého, které by byly vhodné pro filtraci elektroizolačních kapalin v distribučních transformátorech. První část této práce tvoří literární rešerše, která se zabývá tématem elektroizolačních kapalin a jejich degradace, metodami přípravy makroporézní keramiky a jejího využití pro filtraci, včetně přehledu používaných materiálů. Experimentální část se zabývá přípravou porézních filtrů pomocí dvou vybraných metod, replikační metody a přímého pěnění. U filtrů připravených pomocí optimalizovaných parametrů bylo vyhodnoceno fázové složení, mikrostruktura a pevnost v tlaku. Filtry připravené replikační metodou byly tvořeny otevřenými propojenými póry o velikosti 150 až 350 µm, dosahovaly porozity kolem 80 % a pevnosti v tlaku až 2,4 MPa. Keramické pěny získané přímým pěněním dosahovaly porozity 68-73 % a otevřených propojených pórů menších než 100 µm. Filtry bylo nutné zvětšit na rozměry dané filtračním zařízením. Přímé pěnění se ukázalo jako nevhodné pro přípravu filtrů ve větším měřítku, nicméně filtry připravené replikační metodou byly úspěšně zvětšeny a jsou připraveny pro testování jejich filtrační schopnosti. Tyto filtry s otevřenými propojenými póry, unimodálním rozložením velikosti pórů a dostatečnou mechanickou pevností jsou potenciálními kandidáty pro použití v prvním kroku filtrace elektroizolačních kapalin a mohou tak představovat udržitelnější alternativu k v současnosti používaným papírovým filtrům.
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Adaptability of electrospun nanofibers for bone-tissue engineering
Havlíková, Tereza ; Kaspar, Pavel (referee) ; Papež, Nikola (advisor)
The field of bone tissue engineering focuses on developing biocompatible scaffolds, which can successfully mimic the extracellular matrix of human tissue and provide the growing bone cells with the necessary mechanical support and adequate stimulation for proper growth and proliferation. This bachelor thesis describes the basic principles of tissue engineering with an emphasis on the area of bone tissue regeneration, examines current technological challenges and discusses prospective materials and technologies for the design of a compatible tissue scaffold. Electrospun nanofibers, their characteristic properties and adaptability are discussed in more detail. Based on the theoretical findings from the research, a design of a suitable scaffold created from the selected material for following seeding of bone cells, and the planned production procedures are presented. According to the design, the tissue scaffold is manufactured and a series of fundamental research analyses are conducted on it in terms of its structural integrity, chemical composition, wettability, crystalline phase content and cell adhesion. The results of these analyses inform the conclusion regarding the tissue scaffold’s adaptability for bone tissue engineering.
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Coating of tools by the PVD HiPIMS technology
Havlíková, Tereza ; Ohnišťová, Petra (referee) ; Píška, Miroslav (advisor)
This bachelor’s thesis is aimed on the study of PVD coatings of tools with a focus on HiPIMS (High Power Impulse Magnetron Sputtering) technology. As part of the research, the PVD coating methods are presented, then the basic physical processes and characteristics of magnetron sputtering are described and finally the HiPIMS technology is analysed. The aim of the experimental part of this study is to evaluate (Al,Ti)N coating deposited by HiPIMS technology on a wire drawing die. For coated and uncoated die, the wear of the die, surface quality and thermal impact on the wire are observed and compared.
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Psychohygiene from the Perspective of Students of Pedagogy
HAVLÍKOVÁ, Tereza
The bachelor thesis is focused on working with the techniques and principles of mental hygiene of students teachers. The thesis is divided into theoretical and practical parts. In the theoretical part attention is paid to the definition of psychological hygiene, the demands of university studies, coping with emotionally demanding moments, time management and burnout syndrome. The practical part presents the results of qualitative research based on the analysis of interviews with 7 students of the Faculty of Education of the University of South Bohemia. The aim of the investigation is to map and describe how students of teaching manage challenging situations during their studies and how they apply psychohygiene methods. The results of the investigation are compared with previous research on the topic. From the practical part, a recommendation is made that could simplify the work with mental health and facilitate the adaptation to university studies for students studying in the field of education.
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Compatibility of piezoelectric semicrystalline polymerand osteoblastic cells
Havlíková, Tereza
For the improvement of tissue regeneration,functional polymer scaffolds that can mimic the extracellularmatrix of human tissue are extremely desirable. Depending on thetissue that the scaffolds are intended to resemble, these scaffoldsmust satisfy highly precise requirements such as non-toxicity orfibrous structure. High piezoelectricity and hydrophilicity alsoproved to have convenient effects. Due to their innate capability tocreate surface charges under mechanical stress, piezoelectricmaterials such as polyvinylidene fluoride (PVDF) become excellentcandidates for creating functional scaffolds. It is desired for PVDFto also have hydrophilic properties. Otherwise, it could preventadequate cell adhesion and growth necessary for the constructionof biomimetic scaffolds. For this study, electrospinned PVDFnanofibers covered by human or mouse osteoblasts were subjectedto Raman spectroscopy, measurement of the contact angle of theliquid wettability on the sample surface to observe hydrophobicityand hydrophilicity, and scanning electron microscopy (SEM) toassess properties of the material in relation to oxygen plasmatreatment.
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The awareness of health professionals in the field of gynecology about prevention of cervical cancer
Havlíková, Tereza ; Sláma, Jiří (advisor) ; Šimonová, Daniela (referee)
The bachelor thesis deals with the topic of the awareness of health professionals in the field of gynecology about the prevention of cervical carcinoma. The thesis summarizes basic information about primary and secondary prevention, risk factors and clinical symptoms of cervical carcinoma. It also includes information on the diagnosis and subsequent treatment of patients with cervical carcinoma. The main aim of the study was to identify which group of health professionals would have the greatest knowledge of cervical cancer prevention. A total of four research hypotheses were established, of which three were confirmed and only one was disproved. A quantitative type of research was chosen to address them. Data collection was carried out by means of a questionnaire survey conducted at the Obstetrics and Gynecology of the First Faculty of Medicine and General Teaching Hospital in Prague. A questionnaire of twenty-six questions was distributed in paper form among local doctors, midwives and nurses. The final size of the research sample was one hundred respondents. All questions were answered completely voluntarily and anonymously. Tables and graphs summarizing the results of the survey were produced as part of the data analysis. The main finding was that the group of doctors was much more aware of the...
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Piezoelectric Polyvinylidene Fluoride Nanofibers as a Scaffold used for Bone Tissue Engineering
Havlíková, Tereza
The field of bone tissue engineering deals with the issue of developing compatible and non-toxic scaffolds, which provide the growing bone cells with the necessary mechanical support and suitable stimulation for proper growth and proliferation. Polyvinylidene fluoride (PVDF) nanofibers are considered to be a suitable scaffold due to their biocompatibility, fibrous structure, and characteristic piezoelectric properties, which have proven to be an important factor in cell regeneration. For this work, flexible PVDF nanofibers were successfully spun, from which the scaffolding needed for the subsequent settling of cultivated osteoblasts was created. Thereafter the structure and compatibility of this nanomaterial were assessed in relation to the study of cell adhesion to individual nanofibers.
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Coating of tools by the PVD HiPIMS technology
Havlíková, Tereza ; Ohnišťová, Petra (referee) ; Píška, Miroslav (advisor)
This bachelor’s thesis is aimed on the study of PVD coatings of tools with a focus on HiPIMS (High Power Impulse Magnetron Sputtering) technology. As part of the research, the PVD coating methods are presented, then the basic physical processes and characteristics of magnetron sputtering are described and finally the HiPIMS technology is analysed. The aim of the experimental part of this study is to evaluate (Al,Ti)N coating deposited by HiPIMS technology on a wire drawing die. For coated and uncoated die, the wear of the die, surface quality and thermal impact on the wire are observed and compared.
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