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Freezing technology of bull sperm in relation to its survivability and fertilization ability
Doležalová, Martina ; Stádník, Luděk (advisor) ; Jiří, Jiří (referee)
The aim of optimalization the insemination doses production is to provide the highest fertilization ability of spermatozoa during the demanding proces of processing fresh semen and its subsequent cryopreservation. Temperature changes causes spermatozoa damage during the cooling and freezing. Spermatozoa is exposed to cold shock and many others limiting factors, which leads to cell death and therefore to decline of fertilization ability of thawed insemination doses. For increasing spermatozoa resistance, exactly the plasma membrane resistance against cold shock was fraction of egg yolk LDL cholesterol (low density lipoprotein) at various concentrations into the comercially produced diluents added. It is believed that LDL acts possitively to plasma membrane and helps to maintain the fertilization ability of spermatozoa after thawing. Following step in the proces of insemination doses production is slow cooling of diluted semen and equilibration, when the straws are store at cooling box for 30 minutes to 240 hours. This period is necessary to penetrate of certain diluent components into the spermatazoa also maintain the balance between their intracellular and extracellular concentration. Also important is subsequent freezing temperature gradient of insemination doses. The most suitable freezing method is based on computer controlled temperature decline in freezing chamber which allows the precise control of ice crystals formation that could tear and kill the cell.
During 2012 to 2016 was repeatedly collected semen from the group of breeding bulls (n = 27, Holstein and Czech Fleckvieh breed) at AI centre. Semen which fulfill the standard entrance conditions in first step was evenly into several parts divided. For dilution the three types of comercially diluents AndroMed, Bioxcell and Triladyl with and without LDL addition were used. Into the diluents AndroMed and Bioxcell the concentration of LDL 4 %, 6 % and 8% into the dilent Triladyl 6 %, 8 % and 10 % was added. Diluted semen was filled into the glass capillares with volume 0,1 ml and temperature +4 °C. Subsequently the sample was placed to cold bath (0°C) for 10 minutes. Then the volume of capillare with physiological solution (37 °C) was mixed and for next 120 minutes was incubate. The effect of cold shock to proportion of live spermatozoa was evaluated by using Eosin and Nigrosine staining technique during heat test of spermatozoa survivability after spermatozoa heating and after 120 minutes of incubation.
The more suitable semen diluents which provide the higher spermatozoa resistance against cold shock were AndroMed and Bioxcell. Together the possitive effect of LDL addition into the diluents to lower decrease of proportion of live spermatozoa during heat test was found (P<0.05). The most suitable LDL concentration which had a favorable influence at spermatozoa resistance against cold shock was 6 % in diluent Bioxcell. Values of the proportion of live sperm were higher at the beginning of the heat test (+1.31% to + 3.2%) and after 120 minute incubation (+5.82% to +8.41%) compared to other diluents with and without addition of LDL.
In the next step the process of equilibration was optimized, is an important part of insemination doses production. The effect of the length of equilibration for subsequent fertilization ability of spermatozoa was evaluated using spermatozoa motility based of CASA and proportion of live spermatozoa after thawing and during heat survival test lasting 120 minutes (37 ° C). Suitable semen was diluted by comercially used diluent AndroMed based on soya lecithin, filled into the straws (0.25 ml), cooled and equilibrated in cooling box for 30, 120 and 240 minutes and freezed in programmable freezing box applying four types of freezing curves differing in temperature rate decline. There was used standard and by producer recommended 3. phase freezing curve, then 2. phase freezing curve, and 3. phase freezing curve with slower as well as rapid decline of temperature rate in freezing chamber, compared with standard freezing curve. The highest spermatozoa motility was found using 240 minutes of equilibration by +2.72% and +4.58% compared to other lengths of equilibration (P <0.05 to 0.01). The highest proportion of live spermatozoa was found using 120 minutes of equilibration (+6.87 % and +8.68 %). The highest average spermatozoa motility during heat test after thawing was achieved by using 2. phase freezing curve (from +2.97% to +10.37%, P <0.05), also in the proportion of live spermatozoa (from + 4.37% to +8.82%, P <0.01). When evaluating interaction between the length of equilibration and freezing curve (standard 3. phase and 2 . phase freezing curve), the highest average spermatozoa motility and proportion of live spermatozoa using 240 minutes of equilibration by both freezing curves was reached, there was no statistically significant differences. As well as, in all evaluated parts of this study the individual differences between ejaculate of bulls and within semen from one bull (P <0.05) as secondary effect were found.
To maintain good fertilization ability of semen during cryopreservation is necessary to increase the spermatozoa resistance against cold shock using addition of correct concentration of LDL into the commercially used diluents AndroMed and Bioxcell. Subsequently the fertilization ability of insemination dose is influenced by cooling, the length of equilibration and freezing. The length of equilibration 120 minutes and more as well as gentle way of freezing according to freezing curve, which ensures a gradual decrease of temperature in freezing chamber provided the higher average spermatozoa motility and proportion of live spermatozoa.
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Antioxidant, anti-proliferative and immunomodulatory effect of fruits, vegetables and mushrooms in vitro
Doskočil, Ivo ; Havlík, Jaroslav (advisor) ; Orsák, Matyáš (referee)
Recently there has been an increasing interest in discovering of new species of plants and mushrooms which have antioxidant or anti proliferative activity. The interest is caused by the fact that these species have medicinal and food utilization. These properties of plants and mushrooms can be used when dealing with many diseases which may be connected with oxidative stress (inflammatory bowel disease, cardiovascular disease, hypertension, and tumour disease, etc.).
The thesis propounds characteristics of in vitro antioxidant and anti proliferative activity of 19 types of juices and 28 methanol extracts of fruits and vegetables, which are common parts of a diet. In the thesis there are also characteristics of 13 ethanol extracts of edible mushrooms of the order of Polypore (Popyporales). Antioxidant activity was quantifie by 2, 2 diphenyl 1 picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), and inhibition of nitric oxide (NO) production. Cytotoxicity was measured by MTT (3 (4,5 dimethylthiazol 2 yl) 2,5 diphenyltetrazolium bromide. Immunomodulatory activity was determined by an assay of phagocytic activity of human neutrophil granulocytes. Further a total phenolic content (TPC) and total beta glucan content were investigated; these are considered to be the potentially active constituents participating in mentioned activities.
From the obtained results it is evident that juices (TPC = 1603.2 mg GAE/L; ORAC = 438.5 umol TE/g)
and a bilberry (Vaccinium myrtillus) fruit extract (ORAC 836.6 umol TE/g; DPPH = 404.6 umol TE/g) showed
the highest antioxidant activity of all tested samples of fruits and vegetables. Capsicum (Capsicum L.)
juices (TPC = 642.1 mg GAE/L; ORAC = 127.9 umol TE/g) and a radish (Raphanus sativus L.) extract
(ORAC 724.5 umol TE/g; DPPH = 52.2 umol TE/g) also proved to have the high values of antioxidant activity. From the tested fruits and vegetables the following inhibited to produce a nitric oxide: onion (Allium cepa L) juices (lowered the NO production by 57%), tangerine juices (Citrus reticulata Blanco)(by 52%), broccoli (Brassica oleracea var. botrytis italic) extract (by 21%), and orange (Citrus sinensis Pers.) extract (by 10%). Concerning edible
mushrooms, Lentinus tigrinus (Bull.) Fr. (TPC = 216.2 umol GAE/g of extract), Ganoderma lucidum (Curtis) P. Kras (TPC = 257.9 umol GAE/g of extract), and Royoporus badius (Pers.) A.B. De (TPC = 257.8 umol GAE/g of extract) presented the highest phenolic content. Sparassis crispa (Wulfen) Fr. (117.4 mg/g of extract) had the highest content of beta glucan. Substantial effect on phagocytic activity of granulocytes was noticed in connection with Neolentinus lepideus (Fr.) Redhead & Ginns, Polyporus squamosus (Huds.) Fr., and S. crispa. In connection with the latter of mentioned mushrooms, a moderate inhibitory effect towards HT 29 human colorectal adenocarcinoma cell line
(IC50 = 107 ug/ml of extract) was noticed.
The results indicate that the tested plants and mushrooms can be beneficial when reducing the negative effects of oxidative stress. The oxidative stress has been recognized as a contributing factor to a whole range of diseases and the reduction of the oxidative stress may lead to the decrease in the possibility of the diseases´ progression. The results show the possible favourable effects on the human health. When evaluating the results, the following fact should be taken into consideration; the in vitro tests and screenings are considered to be the first phase of systematic research of the effects and serve for the choice of respondents for further detailed studies.
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The profession of social worker in selected states of the USA
Vaculíková, Kateřina ; Pazlarová, Hana (advisor) ; Matoušek, Oldřich (referee)
VACULIKOVA, K. The profession of social worker in selected states of the USA. Prague: Faculty of Arts of Charles University in Prague, 2012. 109 pp. Diploma thesis. The goal of this diploma thesis is to introduce the profession of social worker in selected U.S. states - State of California, State of Iowa, State of New York, and State of Texas. In order to achieve the goal, the thesis first discusses the development and professionalization of social work, the values and ethics within the profession, the forms of the profession regulation and the scope of social work practice in the overall context of the U.S. Subsequently, it describes the specifics of social work profession in the selected states, including geographic and demographic description that significantly influences the focus of social work in each state. In a separate chapter, several aspects of the social work profession in the U.S. and the Czech Republic are compared. The thesis also presents the results of previous research on the public perception of the social work profession in the U.S. The follow-up research part uses the comparative analysis method and determines whether the social workers in the U.S. have realistic notions on the public perception of the social work profession in the U.S. and whether the public perception of the...
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Confidence Cycles and Liquidity Hoarding
Audzei, Volha
Market confidence has proved to be an important factor during past crises. However, many existing general equilibrium models do not account for agents’ expectations, market volatility, or overly pessimistic investor forecasts. In this paper, we incorporate a model of the interbank market into a DSGE model, with the interbank market rate and the volume of lending depending on market confidence and the perception of counterparty risk. In our model, a credit crunch occurs if the perception of counterparty risk increases. Our results suggest that changes in market confidence can generate credit crunches and contribute to the depth of recessions. We then conduct an exercise to mimic some central bank policies: targeted and untargeted liquidity provision, and reduction of the policy rate. Our results indicate that policy actions have a limited effect on the supply of credit if they fail to influence agents’ expectations. Interestingly, a policy of a low policy rate worsens recessions due to its negative impact on banks’ revenues. Liquidity provision stimulates credit slightly, but its efficiency is undermined by liquidity hoarding.
Fulltext:  PDF
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Location-aware data transfers scheduling for distributed virtual walkthrough applications.
Přibyl, Jaroslav ; Sochor, Jiří (referee) ; Sojka, Eduard (referee) ; Zemčík, Pavel (advisor)
Důležitou součástí aplikací procházení distribuovanou virtuální scénou je proces plánování přenosu dat. Jeho hlavním úkolem je zajištění efektivního přenosu dat a maximální kvality renderovaného obrazu. Největší vliv na kvalitu renderované scény mají omezení síťového připojení. Tyto omezení lze redukovat pomocí multi-resolution reprezentace dat scény, určováním priorit stahování jednotlivých částí scény, a přednačítáním dat. Pokročilé metody pro určování priorit a přednačítání částí scény jsou založeny na predikci pohybu uživatele vycházející z matematického popisu jeho pohybu. Tyto metody jsou schopny predikovat následující pozici uživatele jen v krátké vzdálenosti od jeho aktuální polohy. V případě náhlých, ale pravidelných změn směru pohybu uživatele jsou tyto metody nedostatečné co do přesnosti i délky predikce. V této práci je navrhnut komplexní přístup k řešení plánování přenosu dat splňující i tyto požadavky. Navrhované řešení využívá predikci pohybu uživatele založenou na znalostech k určení priority stahování dat i předstahování částí scény. Provedené experimenty nad testovacími daty ukazují, že navržené schéma plánování přenosu dat umožňuje dosažení vyšší efektivity přenosu dat a vyšší kvality renderovaného obrazu během průchodu testovací scénou.
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A NEW DAWN OF NAMING, ADDRESSING AND ROUTING ON THE INTERNET
Veselý, Vladimír ; Muntan,, Jordi Perelló (referee) ; Grasa, Eduard (referee) ; Day, John (referee) ; Švéda, Miroslav (advisor)
Internet roku 2015 se potýká s problémy, které jsou důsledky špatného designu pojmenovávání a adresování v TCP/IP a jež mají přeneseny vliv i na škálovatelnost směrování. Problémy jako růst páteřních směrovacích tabulek, neefektivní multihoming sítí či mobilita zařízení a mnohé další zadávají k otázce, jestli není třeba architekturu Internetu pozměnit. V teoretické části je kvantifikován dopad problémů, možná řešení a zejména je formálně definována teorie kompilujicí poznatky významných publikací zabývajících se problematikou pojmenování, adresování a směrování v počítačových sítí. Tato práce se zabývá dvěma konkrétními technologiemi, jež mají ambicí Internet měnit - Locator/Id Separation Protocol a Recursive InterNetwork Architecture. Výstupem práce jsou vylepšení funkcionality obou výše zmíněných technologií. Za účelem praktického ověření dopadů našeho výzkumu jsou vyvinutý a popsány nové simulační modely pro OMNeT++, které jsou věrné úrovni detailu popisu ze specifikací.
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Srovnání citlivosti 17 ekotoxikologických bioestů pro detekci cyanotoxinů
Maršálek, Blahoslav ; Bláha, L.
Detection potential of some bioassays used for cyanotoxin detection seems to be promising, but the real comparison of results and the sensitivity to cyanotoxins is imposible, because different authors use different cyanobacterial sample with uncomparable toxin composition, different methods for sample preparation, different design of bioassay, media, etc. A critical comparison of alternative bioassays for cyanotoxins detection, which is important for water management is up to date still missing. The aim of the present study was to compare the sensitivity of 17 bioassays for cyanotoxins detection (with respect to the content of hepatotoxic microcystins )using the same cyanobacterial biomass, and the same sample preparation . Additional aims of this study was as follow: i) can the fractionation of cyanobacterial biomass improve the sensitivity and decrease the variability of bioassays? , ii) which bioassay can more precisely dicrimine the presence of microcystins - is there any dose-response relationships? Cyanobacterial biomass was fractionated by SPE-C18 columns. Crude aqueous extracts, "non-toxic" pigment fraction without microcystins and "toxic" fractions (concentrated microcystins) were compared. This fractionation allowed to determine if the toxicity is due to microcystins, or some other not monitored metabolites present in the complex crude extract.
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Cultural Centres
Adolfová, Barbora ; PROKOP, Petr (advisor) ; KAŠPAR, David (referee)
This thesis is concentrated on cultural centres built between years 1960 and 1990 in the former socialist Czechoslovakia. Six cultural centres have been chosen and analyzed to conclude the purposes they serve as well as the programs they offer. These chosen cultural centres are run as municipal organisations financed from the town budgets. The six towns where they are located are similar to each other in terms of their history, size and the time when their cultural centres were built. All of these centres share difficulties with the lack of cultural interest of local citizens, bad technical shape of the buildings in question and low budget.
The aim of this thesis is to compare the functioning of these six cultural centres and conclude whether being directly funded and influenced by the municipal councils has a positive impact and should serve as a model for cultural centres or should be replaced by a different one. It also focuses on cooperation between the management of cultural centres and municipal officials, cooperation with other local cultural institutions and cultural centres from different towns.
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Rescuers, disaster and "librarians"?
Zeman, Jiří
Na první pohled se může zdát, že knihovníci mají pramálo společného se záchranáři a děním kolem mimořádných událostí a katastrof. Domnívám se ovšem, že právě specialisté na informace mohou významně přispět ke koordinaci pomoci při záchranných akcích. Vždyť v jaké jiné oblasti jsou tak potřeba rychlé, relevantní a jasně strukturované informace, jako při záchraně lidských životů? Kdo by měl lépe shromažďovat informace pro následné analýzy a závěry pro zlepšení do budoucna? A kdo by měl mít lepší informace o nejnovějších technologiích a možnostech jejich využití pro přenos informací než právě odborníci na informace? Na několika příkladech si uvedeme, jak mohou knihovníci kooperovat na vývoji "záchranáře budoucnosti", pomoci se systémy pro koordinaci pomoci při katastrofách velkého rozsahu nebo testovat nové technologie pro efektivní využití v praxi.
Slides: PDF
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Characteristics of the working behavior of Czechs and Ukrainians
BYKOVA, Sofia
The aim of this work is to create a transparent and comparable characteristics of the work behavior phenomenon within the cultures of those states - what is common and what is different between them, or maybe incompatible .It is supposed to have some analysis of possible conflicts and their connection with the mentality. The primary reason of this aim choosing is the specialty I study. My work contains information that could be interesting and useful not only for me and my future job, but also for managers and other employees. Overview of examined issues contains specific points, such as the fundamentals of economic psychology and behavioral economics (symbiosis of psychological and economic opinion on motivation and rationality of individuals), theories of motivation and reaction to different occurrence, characteristic of the term "mentality", general points about the human impact of the world economy. For realizing the goals of my work the following hypotheses have been proposed - Czech and Ukrainian mentality have significant differences, though these cultures are close. - Ukrainian and Czech employees are able to work effectively in a team and find a "common language" in the workplace. The difference in mentality does not obstruct on it. - Employers could be interested in the Ukrainian employees taking into account their high concernment and motivation. All three of the hypotheses were confirmed by observed data and comparison of mentality characteristics. Czechs are often tolerant to other cultures, moreover Ukrainian culture is not much different and does not create difficulties in the working relationship. Based on the fact that the chosen company has no conflicts associated with work behavior and differences in mentality, it's hard to define my contribution to this organization work.
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