National Repository of Grey Literature 7 records found  Search took 0.00 seconds. 
Pach vítězství: role feromonů v interakcích raků
MAREŠ, Josef
Analysis of communication, hierarchy, and role of pheromones in crayfish is an interesting area that constantly brings new knowledge and can help us understand some facts that may be valid not only for crayfish but also other crustaceans. In this work, it was therefore studied how the offspring of two females behave in a one tank. After the dominance establishment in females (after a series of contacts and fights), the offspring of preferred a dominant female only, regardless of if their own or a unfamiliar mother. The dominant female, that successfully fought the fights, collected juveniles by its active movement, and they followed its movements. The subordinate female accepted her position, tried to avoid contacts, and reduced its activity. The juveniles practically ignored the subordinate mother at this stage of the experiment. Within the diploma thesis, all set goals were achieved and the newly discovered facts may be an important part of further follow-up experiments. We were able to respond positively to all primary hypotheses when: 1 / Females of marbled crayfish in one tank always established a relationship of the dominant and subordinate one, 2 / marbled crayfish juveniles always chose only one mother in a common tank, and 3 / it was in all cases the dominant one. The results show that dominance (whether communicated chemically or by visual stimuli) is a more important factor for juvenile crayfish than the specific brood pheromeone of their mother. The results bring significant knowledge to the issue of the hierarchy of various chemical and visual signals in crayfish communication. Thus, certain communication signals seem to be superior to others. The "winner odours" are probably stronger than such a strong stimulus as the brood pheromone responsible for recognizing the offspring and the mother. On the other hand, it is not possible to rule out a possible effect of the unattractiveness of the subordinate mother. How the relationships among the subordinate female, dominant female and their offspring would develop in remains opened to further research hypotheses.
Kdo je boss teď? aneb dopad farmaka sertralinu na hierarchii raků
MAREŠ, Josef
Pharmaceuticals' pollution of open waters is a current threat to aquatic organisms. The development of pharmacies and increased consumption of drugs leads to a burden on the aquatic environment with dangerous pollutants. Due to the fast and stressful lifestyle, the consumption of antidepressants increases significantly in the majority of the human population. After consumption and excretion, antidepressants and other drugs enter groundwater and surface water through wastewater treatment plants, which can have a secondary effect on non-target organisms. This master thesis assesses the possible impact of the commonly used antidepressant sertraline on the mutual social behavior of marbled crayfish (Procambarus virginalis). The experiment was based on monitoring the behavior of different pairs of different crayfish. The created dyads assessed mutual interactions between control crayfish, crayfish exposed to sertraline, and reciprocally between both crayfish groups. Three weeks before monitoring, crayfish were exposed to an environmentally relevant sertraline concentration of 1 g?l-1. The results were evaluated by sensory assessment according to available methods, and subsequently, the statistics were assessed. No group of crayfish observed showed a significant difference in behavior. Thanks to the initial phase of experiments of this type, we cannot determine with certainty from the results that sertraline does not affect the social behavior of marbled crayfish. However, along with other antidepressants, sertraline, a selective serotonin reuptake inhibitor, is undoubtedly a potential threat to the environment.
Stravitelnost krmiv pro kapra obecného
MAREŠ, Josef
This bachelor thesis evaluates the composition and apparent digestibility of various types of fish feed and various ingredients applicable to the feeding of common carp. This bachelor thesis also evaluates the suitability of individual components based on the digestibility of individual nutrients. The results show that the right combination of fish feed improves efficiency, reduces feed consumption and increases growth. Last but not least, the negative impact of feeding on the quality of the aquatic environment should be reduced. This bachelor thesis summarizes existing digestibility values of individual feed ingredients for common carp and then its own experiment, which was very time- consuming. Some already known values have been confirmed and some new information about the content of individual components of feed and their subsequent use has been found. The results for wheat and maize were compared with results of other authors. Triticale, daphnia and chironomidae larvae were used for the first time, so the values could not be compared, nevertheless it could be used as a basic information for further research in this area. The average content of individual cereal parameters were: 16% protein content and 64% digestibility, 2% fat content and 70% digestibility, 74% BNLV content and 74% digestibility. Fiber content 5% and ash content 2% with very low digestibility. Phosphorus content 0.6% and digestibility 30%. Average content of individual parameters for natural foods was: protein content 55% and digestibility 86%, fat content 5% and digestibility 74%, BNLV 20% and digestibility 41 %, fiber content 7% and digestibility 8%, ash content 14% and digestibility 30%, phosphorus content 1.2% and 74% digestibility. The resulting element was to determine the most suitable feed for pond aquaculture. According to the available results, wheat combined with natural food is the best option. Wheat is very energy rich, but has a low protein content. Conversely, natural food is energy rich in easily usable protein. The optimal ratio of natural food to wheat was 0.25:2. With this ratio we can meet the ideal nutritional requirements of common carp (31% digestible protein, 0.6-0.7 % phosphorus, 3200 kcal?kg-1 digestible energy). With the right feed, we are able to reduce the negative impact on water quality and this is one of the main goals for the future.
Chování vodních organismů a kontaminace vodních toků? nechtěná léčba deprese a nespavosti u raků
MAREŠ, Josef
This bachelor thesis evaluates the possible effects of pharmaceutically active compounds on non-target fresh water organisms and the risks connected with them. As model organism was used parthenogenetically reproducing non-native marbled crayfish, which were exposed to a mix of five commonly used drugs and one illicit drug - tramadol, citalopram, sertraline, venlafaxine, oxazepam and methamphetamine. The concentration was 1 microgram.l-1 for each of the tested compounds. The main part of the experiment was based on monitoring the behaviour of the exposed and control group of crayfish in arenas with or without shelter. Prior experiment crayfish were exposed for three-weeks to the mixture of compounds mentioned above. The results were analysed in the programme EthoVisionXT and later also statistically evaluated. In the system with available shelters the observed parameters (distance moved and activity) showed significant differences, where the exposed group walked significantly larger distances and was considerably more active than the control group. Exposed group also spent significantly more time outside the shelter. The results in the system without shelter were almost the opposite. The distance moved, velocity and activity were significantly different. The exposed crayfish showed considerably lower activity, velocity and moved shorter distances. The results of this experiment prove that the mixture of monitored compounds can have a significant impact on the behaviour of non-target fresh water organisms. The compounds had a softening effect and can affect sensory receptors of the exposed crayfish, which can have a significant impact on the populations in open waters.
Changes of socio-spatial structure of the city of Kladno during the post-socialist transformation
Slavíček, Martin ; Mareš, Josef (advisor) ; Šimon, Martin (referee)
After the change of political regime in the Czech Republic in 1989, the increasing population differentiation in the income levels and prices in housing market has occurred, as well as selective population mobility. It has resulted in an increasing socio-spatial differentiation at all hierarchy levels. This thesis analyses evaluates and compares the changes of socio-spatial structure of the city of Kladno in the post-socialist transformation period with emphasis on housing estates, which position in the city in terms of social status of the population are expected to decrease gradually. For achieving the goal the quantitative methods were used to analyse the Census data from 1991, 2001 and 2011 at the urban district level. The work is based on the concepts of socialist and post-socialist city. The theoretical part also includes changes of housing estates in Czech cities and some selected post-socialist cities of Central and Eastern Europe. The historical development of the city of Kladno is also included, focusing on its transformation of the social and socio-spatial structure. Key words: post-socialist city, socio-spatial structure, housing estates, Kladno
Time Accessibility of Centres of the Pardubice Region by Individual Car Transport and its Expected Changes in Connection with the Launch of the R35 High-speed Road
Hrbek, Martin ; Mareš, Josef (advisor) ; Marada, Miroslav (referee)
Time accessibility of centres of the Pardubice Region by individual car transport and its expected changes in connection with the launch of the R35 high-speed road Abstract This work is devoted to the time accessibility of centers of the Pardubice Region at the present time (years 2011-2012) and in the year 2040, when, according to available forecasts, the R35 high-speed road should be fully operational. Attention is further focused on the changes of the time accessibility, that might be expected at the end of the period, and also on evaluation of the localization of planned exits from the R35. For a more comprehensive insight into the observed problem, the theoretical part is oriented on the historical development of the R35 as a road backbone of the Czech Republic and on the current state of the road network in the Pardubice Region. Keywords: time accessibility, Pardubice Region, center, slip-road
Evaluation of policy objectives in the management of biodegradable municipal waste in terms of efficiency
Mareš, Josef ; Vejchodská, Eliška (advisor) ; Slavík, Jan (referee)
The work deals with the critical assessment of the requirement of Council Directive 1999/31/EC on the landfill of waste for a gradual reduction in landfilling of biodegradable municipal waste (BMW). The aim of this work was to evaluate this requirement in terms of economic efficiency using the meta-analysis of selected complex studies based on cost-benefit analysis. Studies focused on natural and technical parameters and available specific data for Czech Republic of particular ways of processing BMW were also used for finding of private and social costs and benefits balance. Based on the results of this balance is not possible to decide whether fulfillment of the requirement will increase economic efficiency. Results are calculated from large number of input values, some of which shows significant variability. Oxidation rate of uncaptured CH4 in the process of landfilling BMW is characteristic example. This parameter varies between values 10 % and 90 %. While for value 10 % would separate collection of biowastes and its composting presented option with higher economic efficiency, for value 90 % is the result opposite.

See also: similar author names
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20 MAREŠ, Jiří
6 MAREŠ, Josef
2 Mareš, J.
15 Mareš, Jakub
46 Mareš, Jan
7 Mareš, Jaroslav
1 Mareš, Jindřich
20 Mareš, Jiří
1 Mareš, Jiří A.
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