National Repository of Grey Literature 35 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Ability to Discriminate Floral Morphotypes by Hoverflies
Matoušková, Eva ; Janovský, Zdeněk (advisor) ; Klečka, Jan (referee)
The attractiveness of flowers to pollinators is mediated by several floral traits. The ability to discriminate the flowers based on these floral traits is crucial for the flower reproduction and pollinator nutrition and reproduction. We tested three floral traits - colour, size and shape - along with their combinations using artificially 3D printed flowers on model organism Eristalis tenax in laboratory conditions. Our findings revealed that the most important floral trait was the colour followed by size. Additionally, the effect of colour was enhanced by size, but only for the preferred colour. This suggests that preferences for specific floral traits can be structured. The effect of symmetry was not significant. Subsequently, we observed non-naïve hoverflies and bumblebees in the field on flower patch consisting of devil's-bit scabious (Succisa pratensis). We were interested in the role of other floral traits when the colour and size were indistinguishable. The most important characteristics were height and effective number of florets in the inflorescence. The hoverflies tend to do longer visits than bumblebees and visited more flowers as well. Conversely, bumblebees did shorter but more efficient visits, likely due to their eusociality. Keywords: Syrphidae, Apidae, Eristalis tenax, Bombus spp.,...
Ecological and Evolutionary Processes Driving the Structure of Plant-Pollinator Networks
Hadrava, Jiří ; Klečka, Jan (advisor) ; Gilbert, Francis Sylvest (referee) ; Vujić, Ante (referee)
Associations between flowers and pollinators are responsible for reproduction of majority of plant species as well as food supply for substantial part of animal diversity on the Earth. Until recently, the studies on plant-pollinator relationship were focused predominantly on pollination of particular plant species, with only little or no accent on community perspective. In recent decades, however, pollination ecology shifted its focus rather to community context by introducing so called pollination networks. This approach allows us to view the ubiquity and complexity of the interactions between plants and their pollinators and it opened up many new opportunities to study the pollination from animal perspective or to access spatio-temporal variability in the interactions. However, we still have only limited insight into the processes driving the structure and dynamics of such networks. The assembly of plants, pollinators and their interactions are driven by various ecological as well as evolutionary processes. From the ecological point of view, species co-occurrence in time and space may affect the interactions, or species flexibility for various community contexts providing different food sources may play role. In the evolutionary perspective, species may have various co-adaptations due to their...
Food supplements in strength sports
In this bachelor's thesis on Dietary Supplements in Strength Sports, I investigated whether elite athletes are able to consume sufficient nutrients without dietary supplements and what types of dietary supplements are used by strength athletes. I chose the respondents from three branches of strength sports, those sports are power triathlon, strongman sport and weightlifting. These are the leading athletes in these sectors in the Czech Republic and they are able to outline to me the topic of taking dietary supplements. The theoretical part is focused on the nutrition of athletes. In each section I have discussed a description of strength sports, including the history of strength sports, then I have discussed macronutrients, micronutrients and also the issue of dietary supplements, where I have described the history of dietary supplements and also their distribution. In the theoretical part I drew from books and professional journals. For the practical part of the thesis I set three objectives. The first objective was to map what types of dietary supplements are used by strength athletes, the second objective was to map what amounts of dietary supplements are used by strength athletes, and the third objective was to determine if a regular and complete diet provides the necessary amount of energy and individual nutrients. Ten athletes participated in my research, 9 men and 1 woman. I obtained data from them through a semi-structured interview and from their dietary records. The results show that the respondents are taking 10 types of supplements and 6 out of 10 respondents are able to take sufficient energy from their regular diet. The dietary analysis shows that respondents prefer a diet higher in fat and protein at the expense of carbohydrates, where a higher proportion of fat in the diet reduces the amount of food needed to meet the respondents' energy needs. It can also be observed that respondents do not place much emphasis on fibre intake.
The efficiency of pollen transfer by selected functional groups of pollinators and the ability of plants to influence it
Freudenfeld, Martin ; Janovský, Zdeněk (advisor) ; Klečka, Jan (referee)
Pollinator functional groups differ in their pollen carryover effectiveness and in the importance for particular species of plants, due to specific functional traits of pollinator functional groups. Plant species differ in their specific functional traits too. I determined pollen loads of pollinators by swabbing their bodies with a jelly to compare pollen carryover effectiveness of pollinator functional groups. This helped me to decide which pollinator functional groups are the most and the least effective in pollen carryover. I considered an influence of the last visited flower to make the comparison of pollen loads more accurate. I also calculated proportions of conspecific and heterospecific pollen grains carried on bodies of pollinators to estimate their carryover effectiveness. Likewise, I compared composition of pollen morphotypes carried on pollinator's bodies to find out differences among pollinator functional groups. My analysis shows that pollen carryover effectiveness of particular pollinator functional groups differ. Apis mellifera and solitary bees have the biggest pollen loads, on the other hand, butterfies and small dipterans have the smallest pollen loads. The last visited flower influences an amount of pollen grains carried on bodies of pollinators. Relative pollen loads of some...
Organization of public administration in the Capital City of Prague
Klečka, Jan ; Vedral, Josef (advisor) ; Svoboda, Petr (referee)
of the thesis "Organisation of public administration in the City of Prague" This thesis focuses on complex issue of organisation of public administration in the City of Prague. The reason, which led author to choose this topic, is that there are only few jurists, who dedicate more that several words to this subject in their studies or articles. Therefore this subject matter isn't as explored as for example organisation of public administration in villages or counties in Czech Republic. Aim of this thesis is to go through several sources of information from legislation, judgements and jurisprudence and provide a complex view on current legislation, which regulates organisation of public administration in the City of Prague. Author also tries to add his opinions on some sources. At first we find some theoretical introduction to the topic and brief summary of historical development of the Prague. These facts are used in following chapters. Main part of the thesis is in Chapter Five and Chapter Six. Chapter Five includes description of legislation, which concerned this issue since 1850. This year was not selected casually. It's year of inception of self-government in the Prague. Chapter Six describes activities of administrative bodies, which operate in the City of Prague and its boroughs. Author...
Evolutionary significance of visual traits of flowers and their influence on the pollinator constancy
Haveldová, Alice ; Štenc, Jakub (advisor) ; Klečka, Jan (referee)
Flower constancy is a behavior in which the pollinator visits flowers of the same plant species in a sequence more than would correspond to its preference for the given plant. This behavior is advantageous for plants because it can ensure efficient intraspecific pollen transfer which has a positive effect on their biological fitness. More efficient pollen transfer can lead to the selection of (visual and olfactory) flower traits that encourage flower constancy of pollinators. The main visual floral traits that affect constancy include colour, pattern, shape and size. However, these traits are of different importance for pollinators when they are deciding which flower to visit, and therefore their effect on flower constancy varies. The degree of flower constancy also differs between the functional groups of pollinators. Flower constancy is generally low in vertebrates, but insects and especially representatives of the order Hymenoptera are often flower constant.
Axle detection in the weighing vehicle system
Mičulka, Martin ; Klečka, Jan (referee) ; Šedivá, Soňa (advisor)
This master's thesis deals with the Weight in Motion systems (WIM). The main goal is to create simulation software that detects dual tires assembly with respect to the angle with which the sensor is embedded into the road. Thesis also contains literature search of available solutions of weighing systems and the sensors which are used in these systems. Subsequently, the thesis contains software for recognizing simple assembly or dual tires assembly from real measured data. Software solutions were developed using programming language Python v3.7. All source codes were developed in PyCharm Community Edition 2020.
Network communication monitoring probe
Klečka, Jan ; Fujdiak, Radek (referee) ; Blažek, Petr (advisor)
Master thesis deals with analysis of single board PC which use Linux as operation system. Analysis of individual NIDS systems and examined their properties for choosing right candidate for single board computer which shall be used as network probe for analysis, filtering and logging of network traffic. Part of the work is aimed on development of a interface which is used for configuration of network probe through the web browser. Web interface allows perform basic operations over network probe which influence network traffic or specify, which information shall be logged. Subsequently network parsers were implemented for network protocols using the Scappy library. The conclusion of the thesis contains the design of the security cover for the device according to the IP54 requirements.
Biotic threats to garden monuments: algae, cyanobacteria and invasive plant species
Pergl, Jan ; Perglová, Irena ; Albrechtová, J. ; Antl, Tomáš ; Abarenkov, K. ; Baldrian, Petr ; Cihlářová, L. ; Klečka, Jan ; Kohout, Petr ; Kvasničková, Jana ; Maršálek, Blahoslav ; Maršálková, Eliška ; Pejchal, Miloš ; Petružálková, M. ; Petřík, Petr ; Pyšek, Petr ; Sádlo, Jiří ; Štefl, Lukáš ; Tedersoo, L. ; Větrovský, T. ; Vlk, Lukáš ; Vojík, Martin ; Vosátka, Miroslav ; Zezulka, Štěpán
Chateau, city parks and gardens are perceived as harmonious parts of the landscape. Unfortunately, even these areas have to face various threats, and they can be a threat to the surrounding environment. The exhibition /catalogue presents a look at the organisms that threaten parks. These threats cover unwelcomed invaders covering invasive plants and small microorganisms in the soil, on facades, statues or in water. On the other hand, some species that are intentionally brought to the parks can be risky not only the gardens themselves but also their surroundings.
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Effects Of Apriory Given Homogenouscoordinates Nullspace Constraintson Slam Convergence
Klečka, Jan
The paper aims at the topic of SLAM (Simultaneous Localization and Mapping) algorithms convergence. Standard SLAM algorithms process observations composed of elements which are considered to be independent of each other. Following pages deals with changes that occur on convergence by the apriory assumption that some or all observation elements are bound by some mathematical model. In this case, the considered models are given by nullspace constraints in homogenous coordinates – in other words observed points lies on the same beforehand unknown line or plane. All described experiments are just simulations.

National Repository of Grey Literature : 35 records found   1 - 10nextend  jump to record:
See also: similar author names
17 KLEČKA, Jan
1 Klečka, J.
3 Klečka, Jakub
3 Klečka, Jaroslav
6 Klečka, Jiří
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