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Arctic tundra dendrochronology
Lehejček, Jiří ; Svoboda, Miroslav (advisor) ; Monika, Monika (referee)
Historically unprecedented environmental change in the Arctic ecosystems is often given into the context of its past and possible future development. In the region where instrumental meteorological observations are scarce archives need to be investigated in order to address this issues. The comprehensive synthesis one of the archives: long-live circumpolar evergreen Juniperus communis L. shrub is presented here. 20 individuals from southwest Greenland were investigated at the cell anatomy level to understand the ecology of the species and unhide its potential for environmental and climate reconstructions. The findings are as follows:
i) Stop of exponential cross-sectional conduit-lumen widening with increasing age is in contrast with conduit-lumen nature of trees. This indicates that shrubs do not need to saturate their water and nutrient demands via traits of classical hydraulic conductivity law but rather developed different mechanisms. Extreme weather conditions result in prostrate growth form. However, different weather factors probably influence shrub growth differently: While snow and wind act mechanically (a), temperature influences the form of growth physiologically (b). a) So long as the young shrub stem has high resilience to bend back to an upright position after snow melt and so long as it can withstand the wind during the vegetation season it most likely grows upright and the conduit-lumens widen. b) Temperature, resp. freeze-thaw events are responsible for the shrubs preference of safety (finite size of conduit-lumens) over hydraulic efficiency, thus not allowing for more primary growth. All of these (and other) factors are apparently working together and the transition of vertical to more horizontal growth is gradual. As a consequence, the conduit-lumen sizes may not have to be further increased (due to ecophysiological restrictions possibly also must not) because water is no longer transported against gravity.
ii) Observed age/growth trend has to be taken into consideration for further employment of the wood anatomical parameter in paleoenvironmental studies. That is, shrub cell parameters can only be used for this purposes if correctly detrended. This allows for more accurate as well as longer reconstructions because youth trend was often neglected in reconstructions based on shrub annual-rings.
iii) The south-western Greenland Ice-Sheet (GrIS) melt rates reconstruction is presented for the whole 20th century. This part of GrIS is considered as the most active. According to the presented reconstruction current GrIS melt rates are not uncommon for the last century being comparable to first decades of 20th century. This finding is particularly important contribution to the debate on Atlantic meridional overturning circulation (AMOC). Too high fresh water inputs into the Northern Atlantic from GrIS melting may slow down or even stop the AMOC which would result in more continental climate in Europe. Presented results indicate that this threshold lies higher than observed current melt rates of GrIS.
Fascinating Juniperus comunnis species has shown to be able to address many ecological as well as environmental open questions and due to its longevity and abundant distribution has a great potential to become an important player in the Arctic research.
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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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Frequency stabilized semiconductor laser source for high-resolution interferometry
Řeřucha, Šimon ; Hucl, Václav ; Holá, Miroslava ; Čížek, Martin ; Pham, Minh Tuan ; Pravdová, Lenka ; Lazar, Josef ; Číp, Ondřej
We have assembled an experimental iodine stabilized Distributed Bragg Reflector (DBR) diode based laser system lasing at a wavelength that is in a close proximity to the wavelength of a stabilized He-Ne lasers traditionally used for metrological applications (λ=632.9 nm in vacuum). The aim was to verify whether such a system could be used as an alternative to the He-Ne laser while yielding wider optical frequency tuning range, higher output power and high frequency modulation capability. We have measured the basic characteristics of the laser source and then we have compared the performance of the laser system with that of a traditional frequency stabilized He-Ne laser with a series of experimental arrangements similar to those usually found in laser interferometry and displacement metrology applications. The results indicate that DBR diode laser system provides a good laser source for applications in dimensional (nano)metrology since it provides more output power and advanced tunability options than stabilized He-Ne lasers while maintaining fundamental requirements such as the frequency stability, coherence length and also a defined traceability.\n\n
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Noise, Transport and Structural Properties of High Energy Radiation Detectors Based on CdTe
Šik, Ondřej ; Lazar, Josef (referee) ; Navrátil, Vladislav (referee) ; Grmela, Lubomír (advisor)
Poptávka ze strany vesmírného výzkumu, zdravotnictví a bezpečnostního průmyslu způsobila v posledních letech zvýšený zájem o vývoj materiálů pro detekci a zobrazování vysokoenergetického záření. CdTe a jeho slitina CdZnTe. jsou polovodiče umožnují detekci záření o energiích v rozsahu 10 keV až 500 keV. Šířka zakázaného pásma u CdTe / CdZnTe je 1.46 -1.6 eV, což umožňuje produkci krystalů o vysoké rezistivitě (10^10-10^11 cm), která je dostačující pro použití CdTe / CdZnTe při pokojové teplotě. V mé práci byly zkoumány detektory CdTe/CdZnTe v různých stádiích jejich poruchovosti. Byly použity velmi kvalitní spektroskopické detektory, materiál s nižší rezistivitou a výraznou polarizací, detektory s asymetrií elektrických parametrů kontaktů a teplotně degenerované vzorky. Z výsledků analýzy nízkofrekvenčního šumu je patrný obecný závěr, že zvýšená koncentrace defektů způsobí změnu povahy původně monotónního spektra typu 1/f na spektrum s výrazným vlivem generačně-rekombinačních procesů. Další výrazná vlastnost degenerovaných detektorů a detektorů nižší kvality je nárůst spektrální hustoty šumu typu 1/f se vzrůstajícím napájecím napětí se směrnicí výrazně vyšší než 2. Strukturální a chemické analýzy poukázaly, že teplotní generace detektorů způsobuje difuzi kovu použitého při kontaktování a stopových prvků hlouběji do objemu krystalu. Část mé práce je věnována modifikaci povrchu svazkem argonových iontů a jejímu vlivu na chemické složení a morfologii povrchu.
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The development of the crime on credits in the South Bohemia before 2014
BUŠKOVÁ, Tereza
The aim of this study is to analyze the development of committing a credit fraud offence under § 211 of the Act. no. 40/2009 Coll., the Penal Code (particularly the development of this crime and the development of the amount of the damage) and consequent comparing the selected macroeconomic indicators development in the period 2005-2014 in the region of South Bohemia. In this work secondary data analysis methods were used. Statistical data obtained from the South Bohemian branch of the Czech Statistical Office and statistical data from Crime Police of the Czech Republic was used as the source. The data evaluating the amount of detected cases of this crime committed by the offenders in the Region South Bohemia, according to the region where the fraud was commited, was analyzed. The analyzed file was 5,713 offenses and 4,219 offenders. The defined set was divided into seven parts (districts), according to the local jurisdiction of the territorial departments of the Czech Police. The observed data was compared with selected macroeconomic indicators. From the results it can be concluded that the highest rate of loan fraud offence (calculated per 1,000 inhabitants) is in the district Stra-konice. Conversely, the lowest crime in the same period is in the district Jindřichův Hradec. This work also re-vealed that the development of macroeconomic indicators has no effect on the development of this crime. In conclusion, it is recommended to promote economic education at primary and secondary schools, thus improving the financial literacy of the population. Furthermore, we can recommend the consistent use of, the Central Credit Register, which is already available, as well as supporting of changes in the legislation, so that the providers have an obligation to investigate the credit applicants more and make the offenders of this crime discouraged by higher penalties imposed for credit fraud.
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Appraisement of a family house
VRBOVÁ, Denisa
This bachelor thesis deals with the appraisement of family houses. Real estate market and appraised properties are in the mikroregion Lipno. In the introductory part is described what is the real estate market, valid legislative and basic terms on appraisement and properties. Then there are described methods and approaches based on the market principle and the price regulation. Furthermore the thesis describes the kind of people who appraise properties, experts and appraisers belong amongst them. The begining of the practical part describes the real estate market in Lipno region. The purchase prices and estimated prices of family houses in Prachatice and Český Krumlov regions are compared. The result of the comparison is that higher demand for real estates is in Český Krumlov region. The fact that in Český Krumlov region is higher number of family houses transfer salso supports this result. Then there is described selected family house which is situated in Černá v Pošumaví in Český Krumlov region. Family house is appraised with comparative, value and cost methods.
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Oxygen therapy after cardiothoracic surgery from the point of view of nurses and patients
VRCHOTOVÁ, Klára
Cardiac surgeries are very serious surgical procedures with considerable specific features. This bachelor thesis focuses on oxygen therapy from the viewpoints of nurses and patients. Its theoretical part describes physiology of breathing and the oxygen therapy as such. It describes individual sources of oxygen and indications for oxygen administration. It also describes principles to be observed during oxygen administration. Specific aids are used for oxygen administration, particularly oxygen masks or oxygen goggles. Quality pulmonary rehabilitation is also necessary to make oxygen therapy more effective. Pulmonary rehabilitation is particularly important for patients after a cardiac surgery and it should be practiced even before the surgery. This approach is critical because in the post-surgery period the therapy makes it possible for the patient to breathe and to expectorate properly. Pulmonary rehabilitation is practiced with patients by general nurses at the cardio surgery ward, as well as by physiotherapists. There are various techniques available to determine efficiency of oxygen therapy and pulmonary rehabilitation. The techniques may be classified as invasive and non-invasive; the most frequently used non-invasive method is pulse oxymetry and the most frequently used invasive technique is blood collection for ABR. Two objectives were set for the thesis. The first objective was to map knowledge of nurses about how to provide care to patients treated with oxygen therapy. The second objective was to determine how the patients feel after a cardiac surgery. Two hypotheses and two research questions were formulated. The first hypotheses were: Nurses working at the resuscitation care station have more knowledge about oxygen therapy than nurses working at the intermediate care station. The second hypothesis was: Nurses working at the resuscitation care station have more knowledge about pulmonary rehabilitation than nurses working at the intermediate care station. The first research question was: How do the patients feel during oxygen therapy and pulmonary rehabilitation? The second research question was: How are the patients after a cardiac surgery informed about oxygen therapy and pulmonary rehabilitation? In the research part of the bachelor thesis I have used both quantitative and qualitative research methods. Quantitative processing of data was used for questionnaires filled out by nurses working in the hospitals Nemocnice České Budějovice a.s., Nemocnice na Homolce in Prague and in the faculty hospital Královské Vinohrady in Prague. The method was used for evaluation and assessment of knowledge of nurses working at the resuscitation and intermediate care wards. Quantitative methods were used for processing of data obtained through semi-structured interviews with patients after a cardiac surgery. The data were transcribed and coded using a pencil and paper method. The data were categorized based on the identified codes. Two categories were created: oxygen therapy and pulmonary rehabilitation. Each of the categories was further divided into three sub-categories. Two categories were created for the research oxygen therapy and pulmonary therapy. Three sub-categories were subsequently created for the oxygen therapy and the pulmonary therapy. The quantitative research has shown that the knowledge of nurses about oxygen therapy is higher among the nurses working at the resuscitation care ward. However, the situation is different in case of their knowledge about pulmonary rehabilitation. In this case the knowledge of nurses working at the intermediate care ward was higher. The processed data from the qualitative research have shown that patients do have sufficient information about post-surgery oxygen therapy, as well as about pulmonary rehabilitation. For all patients in the post-surgery period after a cardiac surgery the frequency of pulmonary rehabilitation was higher than 1 per day.
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Consumption of fiber in old age
ŠÁLEK, Jan
The theme of this bachelor thesis is the Consumption of fiber in the old age (seniors). Formerly, the dietary fiber was considered unnecessarily burdensome for human organism. Later, it was found that it has a relatively large impact on human health, especially by serving as a prebiotic for symbiotic bacteria inhabiting the gastrointestinal tract. There is still prevailing opinion that roughage divides into a soluble and insoluble, despite that some types of fiber cannot be definitely classified and placed into any of these groups because they have characteristics of both of them. The daily recommended dose is 30 g. The qualitative research was used for elaboration of the practical part. The first goal was to find out how much fiber seniors consume. The second aim was to compare the consumption of fiber among elderly people living alone and the elderly living in retirement homes built for them. The research group, at the first research question, consists of 20 seniors from the Southern Region aged over 65 years. The research group, at the second research question, consists of five retirement homes from the whole Czech Republic. All respondents were given a record sheet for one week, and instructions on how to fill it. Acquired menus were subsequently re-calculated through the program "Nutriservis Professional". The results show higher consumption of fiber than the average in the Czech Republic, but there is still almost a half missing to get the recommended daily dose. There was observed BMI and its impact on the consumption of fiber. No significant effect was found, because overweight had all interviewees except one respondent. The financial limit is visible for evaluated diet of homes for the elderly, therefore, there are no whole grain products, vegetables and almost no fruit. Despite these limitations, the average consumption of fiber is almost equal to elderly people living alone. In conclusion, there is a proposition how to, despite the low funds, increase the intake of roughage, and avoid or, at least, reduce the problems associated with its low consumption. Recommendations for respondents are individual and given under each evaluation.
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Gluten-free diet - reality in school facilities
JIRÁČKOVÁ, Marie
The topic of this bachelor thesis is gluten-free diet - reality in schools facilities. The goal of this work was to determine the number of school cafeterias in the Vysocina Region which provide gluten-free meals, to evaluate awareness of the canteen staff about preparation of the gluten-free diet and to describe the cooperation between the school cafeteria and family of the pupil with gluten-free diet. School meals are important to provide optimal intake of nutrition during the time the child spends in school, to establish proper eating habits and to better integrate the child into the group of its peers. Gluten-free diet is a necessary medical precaution especially for those with coeliac disease, in which case gluten can lead to villous atrophy, and for those with gluten allergy for whom gluten intake can cause anaphylactic shock. Adherence to the gluten-free diet is recommended also to those with non-coeliac gluten sensitivity diagnosis, although gluten causes only short-term complications, usually intestinal. The method of quantitative and qualitative research was used to make this thesis. The research sample consisted of 8 school cafeterias from the Vysocina Region which provide gluten-free meal to their pupils. Awareness about gluten-free diet principles of the managers of the cafeterias or of the cooks responsible for preparation of gluten-free meal was determined by means of semi-structured interviews. The calculation of the two-day menu of each cafeteria by means of the Nutriservis Profesional program was also part of this thesis. The results were compared with the recommended daily intake of energy, proteins, fat, and saccharides for pupils of elementary and secondary schools. The results of the quantitative research show that gluten-free diet is provided by only a small percentage of school cafeterias in the Vysocina Region. The qualitative research prove sufficient awareness of the cooks about gluten-free diet, with awareness of those cooks directly responsible for preparation of gluten free meals being at much higher level. It was also determined that the cooperation with parents of pupils with gluten-free diet is a usually one time occasion limited to an arrangement of nonperishable gluten free meal packages.
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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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