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Vývoj metodologické a technologické platformy pro neinvazivní odhad fenolických látek v listech a bobulíchŠEBELA, David January 2016 (has links)
Plant optical signals can serve as important source of information about biochemical and physiological processes in plants. These signals are influenced by compounds synthesized by plants during primary or secondary metabolism and thus, can also serve as their qualitative and quantitative indicators. Light reaching plant surface (leaf or fruit) can undergo three main pathways- it can be (i) reflected, (ii) absorbed or it can (iii) transmit through plant material. The probability of these three processes depends on particular wavelength of incident irradiation and on the morphological characteristics of plant tissues themselves. As such, plant contains various spectrum of photosynthetic pigments and fluorescent compounds which can either reflect, absorb or pass incident irradiation through at specific wavelengths. Biophysical techniques working with these optical properties of plant pigments and/or other compounds have become universal and common tool in basic and applied research. To quote some example, chlorophyll fluorescence imaging, UV induced fluorescence or spectroscopic techniques are on the top of interest thanks to its non-invasive nature, allowing maintain the integrity of measured cells or the whole plant constituents. The main aim of this thesis is to provide a comprehensive study on the possibility of non-invasive monitoring of phenolic compounds in the leaves and fruits.
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Phylogeny of Brimstone butterflies (genus \kur{Gonepteryx}): The evolution of colour pattern in UV spectrum and geographical areaHANZALOVÁ, Dana January 2018 (has links)
Phylogeny, phylogeography and evolution of UV reflecting patterns were studied in 12 species of the genus Gonepteryx. Sequences of one mitochondrial (COI) and one nuclear gene (Wingless) were used for phylogenetic analyses and reconstruction of the biogeographical events. The results were later compared with the extent of UV reflecting pattern to construct the ancestral situation and evolution of the UV pattern within the genus.
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Kovariance mezi intenzitou UV-reflektance, tvarem křídla a proměnnými prostředí u Pieris napi (Lepidoptera: Pieridae) / Covariance between UV-reflectance, wing shape, and environmental variables in Pieris napi (Lepidoptera: Pieridae)Stella, David January 2013 (has links)
Visual features of the wing colour, with special reference to the intensity of UV reflectance of the Green-veined White (Pieris napi) were investigated. Several studies revealed that only females of Pieris napi possess UV reflectance on dorsal wing surface. Based on UV sensitive photography, we analysed correlation between environmental conditions (productivity and climate) and 3 patches on forewing of 347 specimens of P. napi from Palaearctic region. Males significantly differ in level of intensity of UV reflectance from females. UV intensity in females is 25% higher in comparison with males. This phenomenon is explained by different deposition of wing pterins. Further, environment significantly affects UV intensity on the forewings of females, but not males. Moreover, we accomplished the analysis of fluctuating asymmetry. First we subjected the environmental variables to PCA. In females, the first PCA axis (temperature seasonality, temperature annual range and longitude) significantly correlated with UV intensity. In males, the second PCA axis (latitude and altitude) was significantly correlated with FA. Additionally, we performed Two-Block Partial Least- Squares (PLS) analysis to assess co-variation between intraspecific shape...
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Hodnocení vodního stresu porostu pomocí metod dálkového průzkumu povrchu / Crop water stress assessment using remote sensing approachERBEN, Jiří January 2017 (has links)
The present thesis deals with evaluation of crop water stress by means of remote sensing. The first part of the research is focused on the assessment of water stress of sunflowers in a laboratory environment using spectral analysis of the reflected radiation and thermography. Leaf of suflowers temperature were evaluated and using them, the index of water stress CWSI were calculated. Reflection of leaf was evaluated in the wavelengths 350 -2500 nm. From these wavelengths spectral indexes were calculated - NDVI (Normalized difference vegetation index) which detect the presence of living green vegetation, WI (Water Index) which serve to calculate the approximate amount of water in the vegetation and RVI (simple ratio vegetation index) which determine the content of biomass or photosynthetic capacity. After that, they were compared with CWSI. Finally CWSI was compared with the spectral data, and from the resulting correlations they were apparent wavelengths, which correlated with given index more or less. The second part is focused on the assessment of water stress in terms of 4th. level catchment, specifically on catchment "Dehtáře" near Pelhřimov. There were primarily evaluated three biggest areas - fields of winter wheat, field corn and TTP.
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Vliv prostředí na tvarovou variabilitu ultrafialových signálů u žluťáska rodu Gonepteryx (Lepidoptera, Pieridae) / Environmental influences on the shape of ultraviolet signals in genus Gonepteryx (Lepidoptera, Pieridae).Pecháček, Pavel January 2019 (has links)
Like many other animals, butterflies are able to visually perceive the ultraviolet (UV) light; many species even have patterns on their wings which are visible in this part of the electromagnetic spectrum. Over the last forty years, it has been shown that these UV patterns play an important role in behaviour of many butterflies, especially in relation to sexual selection - they are involved in the process of recognising a suitable mate, and likely can signal some of the mate's qualities, such as its age, ability to handle stressful environmental factors, or efficiency in foraging. The patterns may also be used for taxonomical purposes. This dissertation thesis contains a comprehensive research into ultraviolet patterns of the Gonepteryx brimstones, with a primary focus on the issue of environmental influences in relation to the expression of these traits, on the patterns' potential role in sexual selection, or on their evolution. It has been successfully demonstrated that UV patterns of at least some Gonepteryx species are affected by the environment to a strong degree, significantly more than the traits not involved in sexual selection. On the whole, the conclusions made by submitted publications suggest that UV patterns play a role in the sexual selection of the chosen brimstones, though it is not clear...
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Prostorová a časová variabilita UV reflektance ve vztahu s proměnnými prostředí u rodu Pieris a Colias / Spatial and temporal variation of UV reflectance in relation to environmental factors in genus Pieris and Colias.Stella, David January 2020 (has links)
A bst r a ct Ultravi olet ( U V) mea ns' bey o n d vi olet' (fr o m t he Lati n - ultra - bey on d), w here by vi oletis t he c ol o ur wit h hig hestfre q ue nciesi n t he'visi ble'lig ht s pectr u m. By'visi ble' we refer t o h u ma n visi o n b utit m ust be ta ke n i nt o acc o u nt t hat h u ma n vis ual perce pti o n is i n c o m paris o n t o ma ny ot her orga nis ms rat her li mite di n ter ms of wavele ngt hsit ca n perceive. isis w hy c o m m u nicati o ni n t he U V s pectr u mis of- te n calle d hi d de n, alt h o ug hit m ostli kely plays a ver yi m p orta nt r olei n t he c o m m u nicati o n of vari o us ki n ds ofi nf or mati o n a m o ng a wi de variet y of orga nis ms. e ai m of t he prese nt t hesis is t o el uci date t he fu ncti o ns a n d relative i m p orta nce of U V pa er ns mai nl y i n L e pi d o ptera fr o m a h olistic ec ol o gical a n d ev ol uti o nar y pers pective. U V re fl ecta nce ca n- n ot be st u die d i n is olati o n: i m p orta nt i nteracti o ns a m o n g several ot her varia bles s uc h as li g ht c o n - dit i o ns, ge neral o ptic pr o perties of nat ural o bjects, t he vis ual s yste m, a n d si g nal pr ocessi n g are t h us disc usse d as well, b ut a n overall e m p hasis o n U V re flecta nce is mai ntai ne d t hr o u g h o ut. M ore over, t his w or k...
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UV znaky ve zbarvení gekončíka nočního (Eublepharis macularius) / UV signs in coloration of common leopard gecko (Eublepharis macularius)Baranová, Veronika January 2018 (has links)
The presence of ultraviolet patterns on body, as well as perception of ultraviolet spectrum by special photoreceptors, is part of sensory ecology of many animal species, including reptiles. Most current research discusses the importance of ultraviolet signs in coloration of diurnal species. The aim of our study was to find out what character have the reflective signs in ultraviolet spectrum in overall coloration of common leopard gecko (Eubplepharis macularius) through a digital photography. The reflective pattern is present in both adults and juveniles and passes as well as the rest of the coloration by significant ontogenetic changes. Another aim was to evaluate the role of ultraviolet reflecting signs in the biology of this crepuscular-nocturnal species. We expect that the pattern contributes to their antipredatory strategies during their first few months of life, and also a white reflecting surface is preserved in adulthood, especially on their tail, which is differently coloured than the rest of the body.
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Zrakové podněty v koevoluci hnízdního parazita a jeho hostitelů / Visual cues in the coevolution of brood parasite and its hostsŠulc, Michal January 2016 (has links)
Avian brood parasitism is an ideal system for the study of coevolution. Brood parasites and their hosts have developed interesting adaptations during co-evolution allowing them to maximize their fitness. The evolution of these adaptations has a character of an "arms race" where the evolution of one trait in the host is tied with the evolution of another trait in the parasite. In my doctoral thesis, I deal with two of these adaptations: recognition of parasitic eggs by hosts and mimicry of eggs in parasites. Since both these adaptations are influenced by birds' visual system, in all my studies I used an objective method to measure the colour and the modelling of avian visual system that is quite different from the human visual system. For instance, humans in contrast to birds cannot perceive ultraviolet (UV) light. However, this part of spectrum influences behaviour of birds substantially (e.g. courtship or foraging). We found that the hosts of brood parasites can use UV light when recognizing parasitic eggs. However, it seems that this part of spectrum is not the main cue in egg recognition (manuscript 1). Ambient light has also an important impact on colour perception. We determined whether the light conditions in nests influence host responses to alien eggs. The Red Bishop (Euplectes orix) was an ideal...
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Neinvazivní měření glukózy v krvi / Non-invasive Blood Glucose MeasuringVítová, Hana January 2012 (has links)
Goal of my master´s thesis is examination of non-invasive blood glucose measurement methods, and designing of device for non-invasive blood glucose reading. The introductory chapter of thesis contains description of know different methods for blood glucose measurement, mainly Near Infra-Red region (NIR) measurement with spectroscopy methods. This project describes pathology of Diabetes Mellitus, specifies how it is divided, and looks also on human metabolism. The theoretical part contains exploration of blood glucose measurement methods. Thesis continues with system scheme design for non/invasive glucose measurement device, based on present knowledge. Major principle of device is measuring with Infra-Red laser, bifurcate optic fiber and photodiode. Design of printed circuit board is also present. Document contains also designs of software diagrams for calibration and processing program written in C# language. Communication between device and computer is made via USB. Microcontroller with C language program is part of designed device. It is used to send measured values into PC and also receives data from computer. This data determines blood glucose concentration and their thresholds.
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Vliv environmentalních proměnných na tvar UV-reflektantní kresby u druhu Gonepteryx rhamni / Influence of environmental variables on the shape of ultraviolet pattern in Gonepteryx rhamniPecháček, Pavel January 2012 (has links)
Many species are sensitive to a light in ultraviolet spectrum. Some species have surface patterns that reflect ultraviolet light. These markings have been observed in many animal taxa; butterflies (Lepidoptera) are no exception. UV-reflectance in butterflies has been primarily connected to sexual selection and in this respect it has been a subject of many studies. In my work I propose an alternative view to this phenomenon. The aim of my work is to reveal how a particular environmental factors influence the morphospace of UV- reflectant patterns and wing shape of the Gonepteryx rhamni (Pieridae). The effect of various environmental factors (latitude, longitude, altitude, mean annual temperature, mean annual precipitation, normalized difference vegetation index - NDVI or net primary productivity - NPP) on wing morphospace was tested using the methods of Geometric morphometrics. I have also studied shape variability among the males and females, specimens from different locations and differences in morphospace of several G. rhamni subspecies. The dataset used in this analysis includes 118 males and 67 females from the Palearctic ecozone. The effect of almost all environmental (except to NDVI and NPP) predictors on shape of the UV-pattern and wing margin was significant in the case of males. In the...
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