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Iniciace pohybu byčíku, signalizace a regulace pohyblivosti spermií ryb: fyzikální a biochemické řízení
PROKOPCHUK, Galina
The current study attempted to shed light on the regulatory processes and response arrangements of fish spermatozoa during the course of maturation and motility initiation. The first intent of this study was to improve the understanding of the mechanism underlying the acquisition of potential for sperm motility in sturgeon. Up to present work, the physiological process underlying sperm maturation in this species has not been described at all. Our results showed that sperm maturation in sturgeon occurs outside the testes because of dilution of sperm by urine and involves the participation of high molecular weight substances as well as calcium ions present in seminal fluid and/or urine. The second aim of the present study was to investigate the coping mechanisms in fish spermatozoa with osmotic and ionic activating mode, as well as in spermatozoa of euryhaline fishes, to various environmental conditions. We showed that alteration of environmental osmolality might affect the fish sperm in different ways, depending on fish species and modes of spermatozoa motility activation either osmotic or ionic mode. In response to osmotic stress caused by hypotonicity, carp spermatozoa regulated the flow of water across their cell membrane and increased their cytoplasmic volume during their short motility period. In contrast, no indications of sperm volume changes were observed neither in sterlet nor in brook trout spermatozoa, both of which having an ionic mode of motility activation. We also examined the mechanism by which sperm motility triggering in euryhaline fishes can adapt to a broad range of environmental salinity. Our results demonstrated that spermatozoa of euryhaline tilapia, Sarotherodon melanotheron heudelotii, reared in fresh-, sea- or hypersaline water can be activated in hypotonic, isotonic or hypertonic conditions of swimming milieu, provided Ca2+ ions are present at various levels. It was established that the higher the fish rearing salinity or the more hypertonic ambient media at spermatozoa activation, the higher extracellular concentration of Ca2+ ions is required. The results obtained in the present study allow suggesting that osmolality is not the main factor inhibiting sperm motility inside the testis in the S. melanotheron heudelotii. A third aim of this study was investigation of the regulation of motility initiation process and description of flagellar beating initiation in chondrostean spermatozoa. We detected that K+ inhibition of sperm motility in sturgeon can be by-passed due to the pre-exposure of sperm cells to a high osmolality shock prior to its transfer to K+-rich swimming media. Thus, we hypothesized that sturgeon spermatozoa may be activated by use of an unexpected signaling pathway, independent from regular ionic stimulation. The successive activation steps in sturgeon spermatozoa were investigated by high-speed video microscopy, using specific experimental situation, where sperm motility initiation was delayed in time up to several seconds. At motility initiation, the first couple of bends formed at the basal region begins to propagate towards the flagellar tip, but gradually fades when reaching the mid-flagellum. This behavior repeats several times until a stage where the amplitudes of bends gradually reach similar value, what eventually leads to sperm progressive displacement. The total period needed for the flagellum to switch from immobility with rigid shape to full activity with regular propagating bends ranges from 0.4 to 1.2 seconds. In conclusion, the results of the current study bring valuable pieces of information into the general understanding of the processes of maturation of fish spermatozoa, their adaptability to different physical and biochemical circumstances, the extra- and intra-cellular signaling as well as the regulatory mechanisms of motility activation in fish spermatozoa.
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The assessment of equine housing systems in terms of welfare
Morávková, Kateřina ; Hofmanová, Barbora (advisor) ; Majzlík, Ivan (referee)
Nowadays, the conditions of animals' breeding are better than they were in the past and bigger emphasis i sput on their compliance and improvement. To secure/provide a good welfare is not an easy task for the breeders. Generally, we know how good welfare should look like, but we do not know, if the animal is satisfied. Various studies and experiments of good and bad life conditions appear. On the other hand, there still are lots of things about the welfare topics, which could be discovered and explored. Other question is, if a bad welfare has something common with animals' cruelty, or does not. One of categories, which is welfare focused on is stablig. When horse breeding and stabling, we should consider their native lifestyle and behaviour. We should do this, if we want to secure a good welfare. In many of cases there is a problem, because as it has been said, there is no strict rule, what is a good and bad welfare. Some horses can be satisfied in a box, and the other can feel bad in the box -- they can have depression and they will feel best when they are out with other horses. Every system and style of stabling has its pluses and minuses. Some of the systems seem to be less suitable for horses, but it depends on the horses' character. But horses do not chooses their kind of stabling, it is choosen by the breeder. The stabling has been solved for centuries, and it must have been solved in the past, it is in the peresent, and it will be in the future. But we still come with new and improved ways of stabling. A modern guy can not imagine, that nowadays stabling should be the same as it was in the past. Today, we do not know, if this way of stabling was found as a good type of welfare and if horses were satisfied with it. It is a question, if better welfare is a box stabling or a styling out. For working horses the best stabling is the lashing one, where horses work in a wood and they want a lot of relax -- through this kind of stabling the rest can be enabled. But according to the law foals can not be roped. To stable the horse with the rope for 22 is a breach of a welfare. So we must alway take the reasons of stabling into consideration and if an exgerrated care about stabling does not verge on a horse's satisfaction. Through the behaviour and understading the horses a guy should be able to recognize, if the horse is fully satisfied and the welfare is arranged in the best way. It should be a reward for the breeders, if the horse has the good lifestyle.
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Some differences in the biology and behavior of the species eastern gorilla (Gorilla beringei) and western gorilla (Gorilla gorilla)
Kotýnková, Nicola ; Kracíková, Olga (advisor) ; Tománek, Pavel (referee)
Genus Gorilla is divided into two species includes four subspecies and one subspecies unrecognized.
Gorillas are the largest living apes and and eight million years ago, as a line, they separated themselves from family Hominidae.
These populations are found in nine African countries and they are separated by forest Congo.
Their most developer sense is vision. The body is adapted for knuckle-walking and their limbs are adapted to grip, with moveable arms and long arms. They have a mighty body with a robust skull and teeth with bumps for processing a hard food.
Gorillas excel significant sexual dimorphism, which is characterized by variously sized body.
Thanks reproduction arises extensive diversity within species in different strategies that help increase fitness. Dominant males mate with sexually mature females, while males with lower status mate with younger females because they are not fertile yet. Compared to that family groups have only one silverback male with which the female mate.
There are substantial differences in eating habits between gorillas. Dietary differences between species and subspecies are caused mainly by food availability. Gorillas are considered for herbivorous and frugivorous animals.
Gorilla groups are polygenic. With one dominant silverback male a few females and their descendants, they form a cohesive group.
They create nest for sleeping every night which different in location and stage of construction.
They communicate with each other through the auditory, visual and chemical signals. They use approximately 102 types of gestures and 17 types of audio signals to communicate.
In wild gorillas using tools is scarce, therefore mainly used to get food from difficult sources most of its body. While gorillas in captivity use tools successfully.
To protect against predators, the female consort with males who protect them.
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Political Aspeckts of Local Government – Voting Behavior of Inhabitans of the Town Jičín
Stránská, Michaela ; Kopřiva, Radek (advisor) ; Lenka, Lenka (referee)
The main objective of this thesis is to analyze the voting behavior of the citizens of the city of Jičín. The theoretical part deals with local democracy, introduces the voting system or different researches of voting behavior. The mainstay of this thesis is the practical part consisting of case study, whose task is to analyze behavior of Jičín citizens. The author of this thesis determined four tasks. First one is the implementation of socioeconomic and demographic characteristics of Jičín, enabling to conclude the voting behavior of its citizens. The other task is the analysis of election results in 2006, 2010 and 2014. Further is analyzed the voter turnout in Jičín and political parties which participated in past years are introduced. The third task is the qualitative research in the form of interview with the Jičínský Demokratický Klub leader and city's councilor. In the last part is conducted quantitative research, which will enable to answer the questions, regarding election behavior of citizens of Jičín.
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Social responsibility and enforcement of ethical principles for Public Administration
Banszelová, Lucie ; Varvažovská, Pavla (advisor) ; Miroslav, Miroslav (referee)
The thesis deals with social responsibility and the application of ethical principles in public administration. Above all, i tis the adherence to ethical principles in conjunction with the Code of Ethics of the Czech Telecommunication Office in Hradec Kralove. The thesis describes the activities of the administrative body of social responsibility and focuses on the ethical behavior of staff towards the citizens who are the users of government services. In the theoretical section briefly describes the important concepts related to ethics, social responsibility and public administration organizations. Attention is also paid to human resources and conditions of the officials in the civil service. The second part is characterized the region in which there is an investigation. In the questionnaire survey among office employees and its clients they are discovered results that highlight the behavior of public officials to the public as part of the issue. The conclusion summarizes the results obtained and reviewed the objectives of the thesis. Acquired knowledge is used for the design of specific recommendations, which should lead to a more efficient behavior of civil servants to the public. In my work I came to the conclusion that most of the office staff are aware of socially responsible behavior. The results made among officials, it was found that officials comply with the set rules of ethical behavior towards our employees and citizens. Survey among citizens was found that they provide officials with information and deal with them with the willingness and helpfulness.
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New trends in consumer behavior when purchasing food
Radoušová, Eva ; Hes, Aleš (advisor) ; Petr, Petr (referee)
This master thesis deals with consumer behavior when purchasing food. For the purpose of this thesis students from the Central Bohemia Region are chosen as a selected group of consumers.
The theoretical part sums up the knowledge related to the shopping behavior of consumers when buying food and influences on this behavior. The second part analyzes the shopping habits of the selected group of consumers. Shopping behavior is examined in terms of frequency of purchase, place of purchase, the most frequently purchased food categories, the main decision criteria when buying food, the impact of advertising and promotional discounts, the importance of information on food composition and the country of origin, interest in organic food and healthy lifestyle, willingness to try new food and approach to food purchases on the internet.
The final part interprets the new trends in consumer behavior of the selected group of consumers and formulates a set of recommendations both for the selected group of consumers and for food retailers.
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Toxoplasma gondii manipulation in the host
Dittrichová, Anna ; Langrová, Iva (advisor) ; Nechybová, Stanislava (referee)
The aim of this bachelor thesis is to collect so far discovered findings about manipulation of behaviour caused by Toxoplasma gondii. The first part of this thesis introduces basic characteristic of the parasite and toxoplasmosis, which is a disease caused exactly by this parasite. In the second part we summarize outcomes of many different scientific essays that deal with manipulation of intermediate host behaviour. Toxoplasma gondii is a widespread parasite that can modify the behaviour of the intermediate host, which can lead to serious changes in psychological profile of infected people. Toxoplasmosis is one of the most common zoonosis in the Czech Republic, the prevalence reaches 25-30 %. Toxoplasmosis is usually an asymptomatic infection, however it modifies the behaviour and acting of the intermediate host in some special situasions, it also changes excretion of important substances and affects the secondary sex ratio too. Toxoplasmosis is a very important risk especially for imunodeficit people and pregnant women. The principle of prevention is very strict personal and food hygiene.
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The Effect of Oregano Essential Oil on Microbial Load, Drying Kinetics and Sensory Atributes of Dried Meat
Hernandez Hernandez, Helga Johana ; Banout, Jan (advisor) ; František, František (referee)
Microbial load can be controlled using either synthetic or natural preservatives. Particular interest has been focused on the potential application of plant essential oils as safer additives for meat. However, there is no published research on the use of essential oils during the meat drying process. This study was focused on enhancing the meat drying process. At first a value-added dried meat product by using oregano essential oil (OEO) to inhibit the growth of bacteria, and the sensorial response from assessors is presented. It was found that the application of the OEO in meat is effective in inhibiting Salmonella enteritidis and Escherichia coli. After 6 hours of drying at 55°C, 2 ml (0.038 ml l-1 air) and 1.5 ml (0.028 ml l-1 air) of OEO were considered the minimal inhibitory concentrations (MICs) against S. enteritidis and E. coli, respectively. Samples treated with 0.75 ml of OEO were more attractive for consumption compared with the control; at a higher concentration of OEO, the sensory quality of the food was affected.
Next, the effect of modified blanching treatments on the drying behaviour of beef meat was evaluated by determining moisture ratio versus time curves and the influence on sensory quality of the resulted product. The 3 treatments under investigation were (1) oil treatment (2) steam blanching and (3) hot air blanching with 3 doses of oregano essential oil (1) 1.5 ml (2) 3 ml and (3) 6 ml. Each treatment had an effect on the drying time of the beef samples, however, the dose of oregano essential oil applied did not affect the drying process. The results showed that steam blanching was very effective reducing the drying time. Meanwhile, 1.5 ml and 3 ml hot air blanching samples and 1.5 ml oil treatment samples were judged as better from sensory point of view and the respondents considered that adding oregano essential oil enriched the pleasantness of the smell.
In conclusion, a value-added dried meat product obtained by using oregano essential oil to enhance food safety received an acceptable sensorial response from consumers. Additionally, each modified blanching treatment tested influences the drying kinetics process, but the dose of oregano applied did not affect the drying process. In this sense, hot air blanching and oil treatment with the lowest dose had an acceptable sensorial response from consumers.
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The Evaluation of Reproduction in Bactrian Camels (Camelus bactrianus) and the Possibilities of Using Non-invasive Methods for Detection of Heat and Pregnancy
Fedorova, Tamara ; Lukešová, Daniela (advisor) ; Jiří, Jiří (referee)
Camels are important husbandry animals which are also often bred in zoological gardens. Unfortunately, camels in European zoos are not usually trained and pregnancy diagnosis in a half-tamed camel is very difficult. Moreover, information of the maternal behaviour of camels is limited. This thesis reviewed current knowledge on camel husbandry, reproduction and behaviour and aimed to 1) examine non-invasive methods of heat and pregnancy diagnosis from urine and saliva in camels kept in zoological gardens; 2) explore their maternal and suckling behaviour; 3) describe experiences with artificial rearing of camel calves. The research into non-invasive pregnancy diagnosis was carried out from 2010 to 2012. Urine from 14 camel females kept in four European zoological gardens was collected and tested using two chemical tests -- the Cuboni reaction and barium chloride test. The Cuboni reaction was significantly (p < 0.01) affected by the pregnancy status of female camels, and its accuracy increased significantly (p < 0.05) in the period leading up to parturition. The barium chloride test did not provide reliable results. Next, the saliva of five adult female camels was sampled for more than one year and concentrations of progesterone (P4) and oestradiol (E2) were measured. The concentrations of P4 (n = 312) and E2 (n = 310) were both significantly (p < 0.0001) affected by the pregnancy status of the animals. Maternal and suckling behaviour was observed from 2003 to 2009 in six zoological gardens, and the presented study includes partial data from this period. Allosuckling (i.e. when a female nurses a non-filial offspring) was described for the first time in camels and it represented 8.58% of all suckling bouts. The non-filial calves suckled more often in the lateral position and preferably joined the filial calf when suckling, so the results support the 'milk theft' hypothesis (stealing of milk) as a main cause of this behaviour. Finally, calf rearing in the Prague zoological garden was summarised and two camel calves were successfully artificially reared. This PhD thesis concluded that 1) the Cuboni reaction with urine and salivary P4 and E2 measurements are suitable methods for pregnancy diagnosis in half-tamed female camels; 2) allosuckling is relatively common in captive Bactrian camels; 3) the artificial rearing of camel calves with a calf milk replacer can be successful.
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Internet nodes localization using synthetic coordinate systems
Švéda, Jaroslav ; Jelínek, Mojmír (referee) ; Komosný, Dan (advisor)
This thesis deals with predicting the latency between two network nodes, such as the two stations, two servers or server and station. The main reason for adoption of effective latency prediction techniques is the elimination of network load caused by unnecessary repeated transmissios or by direct measurement of the latency. Of the many proposed methods of latency estimation, this thesis is focused on methods using artificial coordinate systems with primary focus on the Vivaldi algorithm. Characteristics of the latency prediction methods and properties of various coordinate systems used in practice are evaluated. The issue of the number of dimensions of space defined only by the latency matrix between nodes is also mentioned. Furthermore, some other systems, based on logical clustering of nearby nodes, are mentioned. Description of simulation software VivaldiMonitor developed as part of the thesis is included. The primary purpose is analysis of the behavior of overlay networks implementing Vivaldi algorithm with less than a few hundred nodes. The Vivaldi algorithm is assessed by several simulations carried out using the aforementioned software.
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