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Card of Cryptosporidium infections by humans and animals
BLÁHOVEC, Ondřej
The representatives of the Cryptosporidium genus are one of the causes of gastrointestinal tract diseases in humans and animals. In animals the host may even be a respiratory apparatus. The disease is called cryptosproridiosis. In majority of cases this infection can bypass without any major problems, but in immunosuppressed individuals it can cause serious health problems. Cryptosporidium has a monoxenous development cycle, which basically means that the entire development takes place in a single host. Exogenous stage is represented by oocysts, which are in case of a gastrointestinal disease excreted in faeces. In case of a respiratory disease the oocysts make they way out via respiratory and nasal secretions. This leads to contamination of the environment or water. In general, it is expected that Cryptosporidium isolates, which are present in one class of vertebrates, are not infectious to a non-specific host from other classes. It is also expected that cryptosporidia have low host specificity. But this does not exclude that some kinds have gradually extended its specificity to more species. It is also apparent that cryptosporidium infections are common in animals that inhabit the external environment, so even a human can be endangered by this zoonosis, although the incidence in the Czech Republic is low. The reason for the low numbers may as well be that parasitological examination is not performed very often, so the estimated prevalence in the population is probably much higher. Therefore to reveal the originator of this disease it would be appropriate to perform a parasitological examination in persons who are in contact with animals, this way the cryptosporidium infection would be excluded or proven.
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Use of e-learning education of universal nurses in Militari university hospital - University hospital Prague
JANKŮ, Kamila
The diploma work submitted is called The Use of E-Learning Education of Nurses in the Central Military Hospital Military University Hospital Prague. The theoretical part of the diploma work deals especially with the significance of e-learning, distance learning, history of education of nurses in the Czech Republic and e-learning in health care. In addition, the work includes information of the Central Military Hospital and describes its present circumstances and use of e-learning in the working process. 5 aims and 4 hypotheses were set for the quantitative research. The first aim was to determine the time demands of the e-learning courses study. The second aim was to determine the attitude of general nurses to e-learning education. The third one focused on contribution of e-learning education for general nurses and for the hospital management. The last aim focused on satisfaction of general nurses with the form, contents and diversity of e-learning courses. The fourth aim was used to determine reasons leading for development of e-learning courses for general nurses. Four hypotheses were determined: H1: It takes less time to complete e-learning course studies than regular studies. H2: Nurses younger than 30 years of age prefer e-learning education unlike nurses older than 30. H3: The effectiveness of regular studies is better than the effectiveness of e-learning education. H4: E-learning courses are not as financially demanding as regular courses. The data collection technique consisted in our own anonymous non-standardized questionnaire containing 32 items. The research file consisted of 212 general nurses working in clinical departments of the Central Military Hospital. An additional method was based on a dialogue with the Education Team Manager of the Central Military Hospital. The research results related to the hypotheses show that completing e-learning course studies does not take less time than completing a regular course. Nurses younger than 30 years of age do prefer e-learning education contrary to nurses older than 30. The effectiveness of regular courses in contrast to e-learning education has not been confirmed as well as the fact that financial demands of an e-learning course are lower than financial demands of a regular course. Further, nurses prefer regular forms of studies, mostly with their passive participation in an educational event; however, they find completion of e-learning courses more convenient. Most respondents also expressed a positive opinion on the form, contents and diversity of e-learning courses. Courses include enough information for preparation of a final test and nurses find the number of courses necessary for periodical evaluation adequate. What they consider limiting is the impossibility to retake the final test; they mostly suggested it should be allowed to take the final test twice or three times. The research implies that a higher percentage of the respondents spend as much time as they want studying. Nurses still prefer regular forms of studies with passive participation to the e-learning form. Most nurses have a positive opinion on the current contents of courses in the form of a text format. The course topics are mostly based on suggestions by members of the Non-Medical Professions Education Team of the Central Military Hospital. The research results will be presented at the next regular meeting of members of the Non-Medical Professions Education Team of the Central Military Hospital. Procedures for improvement of the form of the current courses will be presented and proposed as well as the possibility to develop communication between the author and students, the limiting impossibility to retake final tests and the suggestions concerning the number of possibilities to retake them.
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Strategie oplozování u ryb s vnějším oplozením
SIDDIQUE, Mohammad Abdul Momin
Morphological properties, species specific differences, development, and function of egg envelopes are of importance for a better understanding of fertilization strategies as well as for captive reproduction. We reviewed morphology and the developmental stages of egg envelopes, mechanism of polyspermy block, and also the role of micropyle and cortical granules in polyspermy block for acipenserid eggs. The structure of the egg envelope is similar among the acipenserids, comprising an external envelope (thecal cells, basal lamina, and follicular epithelium), a five-layered oocyte envelope (adhesive layer, alveolar layer, epilayer, and zona radiata externa and interna) and a layer of oocyte matrix and cortical granules. The development of acipenserid egg envelope within the ovary comprises five stages, with further changes following fertilization. Moreover, we standardized the terminology used to describe the egg membranes which can minimize the confusions and be helpful for future work on acipenserids eggs as well as for other fish species. The sperm to egg ratio (required to fertilize eggs) and effects of pre-incubation of eggs in freshwater before fertilization were studied to standardized fertilization protocols for sterlet Acipenser ruthenus. Pre-incubation time had no effect on fertilization success at 430,000:1 and 43,000:1 sperm to egg ratios, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5 min pre-incubation increased the fertilization rate than 10 min. Transmission electron microscopy showed that pre-incubation of eggs in water for <10 min did not trigger a cortical reaction, suggesting that a low sperm to egg ratio 0.5 to 1 min pre-incubation of eggs in freshwater prior to fertilization can enhance fertilization rate of sterlet (minimally do not change fertilization). The effects of pre-incubation in seawater and the duration of egg receptivity were determined for fresh and over-ripe sea bass eggs. Our results revealed a significant effect of pre-incubation time for both the fresh (P < 0.01) and over-ripe eggs (P < 0.01). The fresh eggs had a higher fertilization success than over-ripe eggs. Fertilization success of eggs significantly declined for both of these treatments after 3 min of pre-incubation clearly indicated that sea bass eggs are able to be fertilized by sperm for up to 3 min after release into seawater. Effects of pre-incubation of eggs and activation medium on the percentage of eyed embryos for Ide Leuciscus idus were examined. At the eyed-egg stage, pre-incubation time was significant for the freshwater activation medium (P < 0.001), such that the percentage of eyed embryos declined across the pre-incubation time gradient. Activating medium had a significant effect on the percentage of eyed embryos for each pre-incubation time (P < 0.05). More precisely, freshwater produced the lowest percentage of eyed embryos at all pre-incubation times, whereas saline water and Woynarovich solution produced the highest percentage of eyed embryos at 0 s and 30 s before incubation. Examination of sperm traits showed no impact of activating medium on computer assisted sperm analysis parameters. Our results suggested that saline water or Woynarovich solution improve fertilization rate in Ide during fertilization. In conclusion, this thesis provides basic knowledge on gamete biology, role of egg receptivity period, effects of pre-incubation of eggs and different activating medium which can be useful to understand the fertilization strategies of different externally fertilizing fishes as well as standardize their fertilization protocol for captive reproduction.
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Vliv teploty vody a intenzity světla na raný vývoj sumečka afrického v komerčním chovu
PROKEŠOVÁ, Markéta
The successful production of quality early fish stages is crucial for artificial rearing fish species. Nevertheless, it is quite a problematic process, because fish as poikilothermic organisms are highly sensitive to various environmental conditions. Moreover, both fish embryos and larvae are more affected by biotic and abiotic factors (such as predation, stocking density, temperature, light, pH, salinity, oxygen saturation, feeding availability, or their interactions) than older juveniles or adults. Most fish processes such as reproduction, metabolism, survival, development and growth can be considerably (positively, negatively or not) influenced by these conditions. Therefore, it is important to understand their impacts on fish stages during embryonic, larval, juvenile, adult, and eventually the senescent period. Then, following the application of new knowledge to the practise, especially species- and age-specific optimal conditions, should result in higher survival, better growth rate, well developed fish without deformities and lower cannibalism. The objectives of the present thesis were to assess the effect of water temperature and light intensity on the early development (embryonic and larval period) of African sharptooth catfish as a perspective fish species for freshwater intensive aquaculture. Due to its great characteristics (for instance fast growth, ability to breathe atmospheric air, rearing at high stocking density) this species can meaningfully contribute to the global aquaculture production which is expected to rise in the coming years. However, there are still some difficulties in the early rearing African sharptooth catfish regarding the cannibalism, feeding, survival and necessity of detailed information about the effects of some abiotic factors and their interactions.
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The effect of pyrethroid based pesticides on fish
RICHTEROVÁ, Zuzana
Pyrethroids are ones of the most used pesticides worldwides. The widespread use and high stability of pyrethroids lead to the assumption of that their occurrence in the environment could be quite frequent. They can reach water ecosystem as pollutants. Residues of pyrethroids are not only detected in the water column, but also in sediments and in fish tissues. The first study was devoted to the product Nexide containing 60 g.l-1 of active substance gamma-cyhalothrin. Tested Nexide concentrations were 5, 25, 50, 100, and 250 µg.l-1. Early life stage test was used.Common carp (Cyprinus carpio) was tested. There were significant mortalities in all concentrations except the lowest concentration during the trial. The lowest concentration tested 5 µg.l-1 only caused a slightly increased mortality. This lowest concentration influenced the growth in length and weight negatively, decelerated ontogenetic development, and made the body surface of the individuals darker. Histopathology of individuals from this concentration revealed dystrophy in liver. Examination of kidney, intestine and gills did not show significant histopathological differences compared with control. The evaluation of selected parameters of oxidative stress demonstrated a significantly higher activity of detoxification enzyme glutathione-S.transferase (GST) and a significantly lower activity of defensive enzyme glutathione peroxidase (GPx) compared with the control group. The other examined parameters of oxidative stress such as catalase (CAT), glutation reductase (GR), and lipid peroxidation determined by using the thiobarbituric acid-reactive substances (TBARs) were comparable to the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Nexide in the given concentration leads to dysbalance of defensive enzymes. The second study was devoted to the product Cyperkill 25 EC containing 250 g.l-1. Tested Cyperkill 25 EC concentrations were 7.2, 36, 72, 144, and 360 µg.l-1. The procedure of the trial was the same as the preceded one. There were 100% mortalities in all concentrations except the lowest concentration during the trial. The lowest tested concentration 7.2 µg.l-1 allowed 90% of individuals to stay alive till the end of experiment. The lowest concentration influenced the growth in length and weight negatively and decelerated ontogenetic development compared with the control. Any individual exposed to this concentration did not reach juvenile stage until the end of the trial. Dark pigmentation was visible in 68% of these exposed individuals on the last day. Similar darkening was visible in individuals from higher concentrations shortly before death too. Histological examination did not revealed significant changes in intestine, liver, kidney, and gills compared with the control group. Evaluation of selected parameters of oxidative stress demonstrated significantly lower activities of GST, GR, and GPx. Activities of CAT and TBARS were comparable with the control group. Changes in oxidative stress parameters suggest that exposure of the organism to the product Cyperkill 25 EC in the given concentration could induce oxidative stress and interfere with the activities of antioxidant enzymes. The presented thesis summarises actual data about pyrethroids and their influence on fish. The demonstrated effects confirm high susceptibility of early developmental stages of fish to tested pesticides. When interpreting the results, we have to take into account the fact that studies showed this risk even on single pyrethroid substances. But water organisms are exposed to many other more or less toxic products and substances in a real environment. These xenobiotics could react with each other and their mixture could even potentiate negative effects. The performed studies also clearly show the significant differences in the sensitivity of embryonic and embryolarval tests.
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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 use of (nano)oxides for metal and metalloid stabilization in contaminated soils
Michálková, Zuzana ; Komárek, Michael (advisor) ; Luke, Luke (referee)
The main objective of the thesis was to evaluate the potential of selected Mn and Fe (nano)oxides for the stabilization of metals and metalloids in contaminated soils. The research was focused basically on three materials - commercial nanomaghemite (Fe III), nanomagnetite (Fe II,III) and a synthetic amorphous Mn oxide (AMO). The main aim of the work was to provide a complex view on the chosen stabilizing amendments regarding not just their direct influence on contaminants mobility and stabilization mechanisms, but also their stability and alterations in soil conditions together with influence on soil microorganisms and higher plants. Firstly, adsorption properties of the tested materials towards Cd, Cu, Pb and As were investigated. In this context, the most effective material showed to be the AMO reaching one to two orders of magnitude higher adsorption capacities than Fe III and Fe II,III under given experimental conditions. Interestingly, the rate of As(V) adsorption onto AMO was increasing with increasing pH as a result of high pHzpc of the AMO (8.1) and significant dissolution of this phase at lower pH values. As a next step, the influence of (nano)oxides on metal(loid)s mobility and other physico-chemical soil characteristics after application to contaminated soil was examined. Again, the AMO proved to be the most efficient in reducing mobile pools of Cd, Cu, Pb, Zn and As. On the other hand, Fe III and Fe II,III addition had generally less significant effects on contaminants mobility. AMO application further resulted in an increase of soil pH connected with AMO dissolution and unwanted decomposition of soil organic matter. When (nano)oxides alterations in soil conditions were observed, MnCO3 coatings were identified on AMO surface while no significant changes were recorded for Fe III and Fe II,III. As the MnCO3 formation was connected with increased AMO stability, AMO particles synthetically covered with MnCO3 coating (denoted as SM AMO) were prepared. Although the SM-AMO had a lower mass loss in soil than pure AMO, the stabilizing efficiency was almost the same for both materials. The differences in surface composition of both materials were decreasing with time as MnCO3 naturally precipitated on the AMO surface in soils while the SM AMO coating was gradually dissolving. When investigating the effect on soil microbiota, AMO efficiently promoted soil microbial activity while no significant changes were observed in the case of Fe III and Fe II,III. The AMO was also able to reduce the uptake of Cd, Pb and Zn by sunflower (Helianthus annuus L.), eliminate Zn phytotoxicity symptoms and increase biomass yield. On the other hand, toxic levels of Mn released from the AMO in an acidic soil were found in sunflower tissues. AMO application is thus recommended for contaminated neutral or slightly alkaline pH with a higher cation exchange capacity in order to avoid unwanted release of Mn. Finally, various types of AMO-biochar composite sorbents were recently prepared and field experiment focused on stabilization of Cd, Pb, Zn and As using studied materials is currently under preparation. The combined results from the thesis highlight the importance of a complex experimental approach dealing with all parts of the contaminated soil environment in order to obtain complete information about the efficiency and usefulness of any newly developed stabilizing amendment.
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Management of production populations of forest tree species utilizing methods of mathematical programing
Hořejší, Matouš ; Lstibůrek, Milan (advisor) ; Stejskal, Jan (referee)
Breeding of forest tree species is a great opportunity for the entire forestry sector to succeed in the present modern World. Genetically improved forest trees have much better growing quality and they can sustain higher stress and unfavorable climatic conditions.
Efficient algorithms are necessary for optimizing and establishing seed orchards. These should optimally select clones as parents in future seed orchards. In the present thesis, we developed model, based on mathematical programming methods, which creates mix of clones with the maximum breeding value and constraints on genetic diversity.
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Psychology of advertising
Musil, Jaroslav ; Michálek, Pavel (advisor)
This thesis looks into one of the most used marketing mixes of tools, commercials. The main part explores the effect of commercials directly on the end-users, on their shopping behaviour and how it effects their decisions. The first, theoretical part focuses on analyses and defining of basic parameters of a psychological commercial which is needed for implementation of the research part. The research was done with the help of the questionnaires when questions both open and closed were asked. The second part of the thesis presents the outcomes of the research, for the purpose of which were selected the aim groups like children and their parents. For higher objectivity two types of questionnaires were used, separate for children and parents. Based on the gained data it was detected that both children and parents are effected by commercials. One outcome of the questionnaires is that children do not realize the effect of the advertising, while their parents are aware of its effects on them.
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Evaluation of genotypic response of winter wheat production interventions
Bláha, Tomáš ; Faměra, Oldřich (advisor) ; Pavel, Pavel (referee)
Sources used in this thesis concerns the cultivation, the development and the growth of wheat and its recommendation for agro-ecological conditions such as requirements for the crop, influence of the agricultural technologies to underground parts, fertilization of wheat, the optimum sowing date and sowing depth. In the next part of literature search there is an information about response of winter wheat for chemical protection including treatment morforegulator of growth. The end of literature search deals with the composition of wheat grain and its potential influence to quality.
The methodological part is devoted to independent description of characteristics of the varieties which are included in experiment. Data for evaluation are based on literature published by ÚKZÚZ. This part summarizes the equipment used for conducting an experiment. Equipment consists machinery and laboratory equipment.
The experiment was located at two places - in Úhřetice near to Chrudim and in Krukanice near to Plzeň. Both places are valuated in the essay - description of altitude, soil type etc.
Evaluated results of experiments are at the end. The conclusion of my thesis is that more comfortable climate for growing wheat is in Úhřetice - the average yield is for almost 20 % higher than in Krukanice. Other conclusion is about late sowing date which reduces yield and about increasing number of antifungal treatment increases the yield. Each of the varieties are valuated in the next part and the best treatment options for them are recommended. One fungicide treatment is proposed resistance to disease (Bohemia, Seladon), dual fungicide treatment is recommended for the rest of varieties. Field evaluation of disease shows that intensity of the treatment must respond to the current situation (according to the year).
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