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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.
41

Analýza kvality života u pubescentů a adolescentů s ohledem na cirkadiánní a diurální rytmy v dětských domovech v Jihomoravském kraji / Analysis of the quality of life of preadolescents adolescents with regard to circadian and diurnal rhythms in children's homes in the South Moravian Region.

PEVNÁ, Radka January 2013 (has links)
The thesis deals with analysis of the quality of life of preadolescents and adolescents with regard to circadian and diural rhythms in children's homes in the South Moravian Region. The first part characterises concepta of quality of life, pubescent, adolescent, circadian and diural rhythms. The work is focused on the temporal area of quality of life. It described the importance and quality of sleep, sleep cycles and sleep typology. The research deals with the questionnaire survey a total of 110 respondents (60 pubescent, 50 adolescents). The research method consists of a selection of questions from a standardized questionnaire circadian typology, CIT Harada, Krejčí, 2010. The data are analyzed using basic statistical methods
42

Analýza kvality života u pubescentů a adolescentů s ohledem na cirkadiánní a diurální rytmy v dětských domovech v Pardubickém kraji. / The Quality of Life Analysis with Regard to Circadian and Diurnal Rhythm of Pubescents and Adolescents in Children's Homes in the Region of Pardubice.

ŠTORKOVÁ, Tereza January 2014 (has links)
This thesis deals with the quality of life of pubescent and adolescent in children's homes in the Pardubice region with regard to circadian and diurnal rhythms. In the theoretical part we define in detail the concept of quality of life, pubescence, and adolescence, biorhythms with a division between circadian and diurnal rhythms, sleep and institutional care. More attention is paid to sleep, its importance, quality and above all sleep cycles that are directly associated with the subsequent research area. In the research section, four research assumptions are made. Subsequently, we process data from eight orphanages acquired in the period from December 2011 to June 2012 in the Pardubice region. The questionnaire survey has 125 respondents of which 59 are teenagers in the age range 10-14 years and 66 adolescents between the age 15 and 18. For this purpose we used a shortened version of the standardized questionnaire for circadian typology CIT - Harada, Tailor (2010). The data was evaluated using basic statistical methods. It was found that on weekdays pubescents averagely go to bed at 09:15 pm and get up at 6:45 am. On weekdays, the average sleeping time is 9.5 hours. On the weekend pubescents averagely gone to sleep at 10:30 pm and get up at 8.30 am. The average weekend sleep is 10 hours. Adolescents go to sleep on average at 10:00 pm and get up at 6:45 am on weekdays. The average sleep on weekdays is 8 ? hours. On the weekend adolescents go to sleep on average at 11:15 pm and get up at 9:15 am. Which means that the weekend sleep is an average of 10 hours. Three assumptions were met, and that, the average sleep time for pubescents on weekdays is longer than the average duration of sleep in adolescents. Adolescents have a bigger problem getting up on weekdays before puberty. Pubescents evaluate their sleep rhythm from a diurnal perspective as sufficient. One assumption was refuted and that is, adolescents sleep on average less during the weekend than their pubescent counterparts. The research was useful as it brings together the issue of the quality of life of adolescents in educational institutions and can serve both for further research and as an indicator of the quality of life.
43

Návrh interiérového svítidla v trendu Human Centric Lighting / Design of indoor lighting in a trend of Human Centric Lighting

Ruml, Filip January 2018 (has links)
The main tasks of the thesis lie in summary of present state in Human Centric Lighting field, in the optical design of luminaire and in practical verification of the proposal. The design is developed in software LightTools and for the verification of functionality the software Dialux EVO is employed. The luminaire is designed primarily with respect to the influence of light on the man and the physiological, psychological and behavioural responses in humans. The thesis is created in cooperation with the company Robe Lighting s.r.o. The proposal of the luminaire corresponds to the current state of knowledge in the area of light influence on humans. The designed luminaire in the trend HCL is distinguished by the high quality of emitted light but also with higher costs of the operation.
44

Meziroční dynamika výskytu šelem a kopytníků v české krajině / Between-year dynamics of carnivores and ungulates in the Czech landscape

Schnebergerová, Adriana January 2022 (has links)
It is important for the ecological management of wildlife populations in the Czech Republic to know the composition of species in individual habitats. This will allow predictions on the reactions of wildlife based on evolving changes that will occur sooner or later in these habitats due to human activity and natural change of our environment. Camera traps are a powerful tool of the 21st century with which we are able to observe wildlife without major interventions in their lives. With the right experimental design, camera traps allow us to find out details about wildlife life such as their distribution and habitat preferences, population structure, and their behavior. In this work, I used camera traps to determine the species composition of two groups; ungulates and carnivores in different habitats. This thesis analyzes the habitat preferences and hepls to find out to what extent the spatial patterns of occurrence on these two groups are in the monitored habitats over the course of a couple years. Data collection took place from June 2015 to May 2017 in the Central Bohemian Region northeast of Prague. Despite the fact that the area is densely populated and agriculturally exploited, I was able to capture four species of ungulates and nine species of carnivores on a total of 73 camera traps in this...
45

Úloha črevných cirkadiánnych hodín v epiteliálnom transporte, proliferácii a tumorigenéze. / Role of intestinal circadian clock in epithelial transport, proliferation, and tumourigenesis

Soták, Matúš January 2014 (has links)
AABBSSTTRRAACCTT The molecular circadian clock enables anticipation of environmental changes. In mammals, clocks are ubiquitously present in almost all tissues and they are comprised of transcriptional-translational feedback loops of the so-called clock genes. The central clock represents the intrinsic pacemaker which is located in suprachiasmatic nuclei (SCN) of hypothalamus and synchronizes peripheral clocks. Clockwork system in alimentary tract and its regulatory link to intestinal functions are poorly understood. Therefore the objective of the thesis was to characterize molecular clock in particular parts of the rat intestine and to elucidate its link to the intestinal transport, regulation of cell cycle and neoplastic transformation in colonic tissue. We used quantitative RT-PCR (qPCR) to determine circadian profiles of mRNA expression of clock genes in the epithelium of duodenum, jejunum, ileum, and colon of rat. Furthermore, we analysed the expression of genes coding sodium chloride transporters and channels as well as cell cycle regulators in colon. To focus more precisely on different structures of intestinal epithelia we used laser capture microdissection. In addition, we performed Ussing chamber measurements to determine the colonic electrogenic transport. To study the contribution of circadian...
46

Vliv endokanabinoidního systému na světelnou synchronizaci cirkadiánního systému potkana / The effect of endocannabinoid system on light entrainment of rat circadian system

Filipovská, Eva January 2018 (has links)
Circadian system of mammals is generated in suprachiasmatic nuclei of hypothalamus. This system is synchronized with light conditions through phase shifts that occur after light exposition during the subjective night. Recent studies have shown that activation of endocannabinoid receptors attenuates the light-induced phase shifts and influences the ability of circadian system to light entrainment. The aim of this work is to examine this influence on behavioral level and on light-reactive cellular processes within the suprachiasmatic nuclei. Our results show that the activation of endocannabinoid system via CB1 receptor agonist modulates the light-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and the expression of c-Fos protein in neurons of suprachiasmatic nuclei in the rat's brain; these cellular processes correlate with the attenuation of light entrainment. Keywords: circadian system, suprachiasmatic nuclei, light entrainment, endocannabinoid system, CB1 receptors, extracellular signal-regulated kinase 1/2, ERK1/2, c-Fos
47

Osvětlování s ohledem na biologické funkce / Illumination with respect to biological functions

Němec, Jiří January 2018 (has links)
The paper summarizes the basic light-technical parameters, the principles of visual and non-visual photoreceptions and the effects of light on the organism. Several chapters focus on the mechanism by which light affects hormone levels and the circadian rhytm of the organism. In relation to the lighting system, the impact of electromagnetic radiation, associated with the controls, on the body is also considered. Briefly described are systems based on smart LED light sources or smart switches. The result of the thesis is to choose the solution that best suits the requirements of the contracting authority.
48

Fotobiologická bezpečnost svítidel a světelných zdrojů / Photobiological Safety of luminaires and Light Sources

Štěpánek, Jaroslav January 2020 (has links)
This doctoral thesis called “Photobiological safety of luminaires and light sources” has focused on an optical radiation and its relation to human body. The thesis describes possible consequences on living tissue during excessive exposure to optical radiation. Among others the work deals with the light source, lamp and optical devices evaluation in dependence of photobiological safety. There is created a method of light source evaluation procedure for photobiological safety in accordance with ČSN EN 62471. The meaning of this procedure is based on its hazard calculation from measured values of irradiation to different photometric distances. Validity of procedure is verified by light source measuring, in which visual angle and photometric distance have been changed. There we can also find an application of this procedure in the UV source evaluation, which helps to determine a safe distance away from UV sources not to create any danger. The evaluated UV sources include a UVA luminaire with a dominant wavelength of 365 nm or an arc of an electric welder. The thesis also describes a method of evaluating light sources for blue light hazard for an aphakic and pseudophakic eye. This method can also help to determine the hazard for the eye without lens or with some implanted lens. Furthermore, there was developed the method of the blue light hazard assessment depending on the age of an exposed person. In terms of the work there was also created a computer programme evaluating photobiological safety resulting from the spectral data having been stored in the library programme or from spectroradiometric measurement data. The work also marginally deals with the topic of circadian rhythms, which are closely related to photobiological manifestation in an human body. Above all the work compares light sources for which equivalent illuminances are calculated, consequently light sources have the same effect on suppressing the melatonin hormone production.

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