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NUMERICAL ESTIMATION OF MICRO-CRACK PATHS IN POLYMER PARTICULATE COMPOSITE
Majer, Z. ; Náhlík, Luboš
Determination of composite mechanical behavior is one of important part during the composite tailoring. The aim of the present work was to estimate a micro-crack behavior in a polymer particulate composite. The composite was investigated by means of the finite element method -using ANSYS software. A two-dimensional three-phase finite element model was developed to analyze the crack growth behavior. The assumptions of the linear elastic fracture mechanics were considered and the Maximum Tangential Stress (MTS) criterion was used to predict the direction of the crack propagation. The effect of the elastic modulus of the interphase on the micro-crack propagation was investigated. The properties of matrix and particles were taken from experiment. It was shown that the interphase properties influence the stress intensity factor KI as well as the micro-crack paths. The results of this paper can contribute to a better understanding of the micro-crack propagation in particulate composites with respect to the interphase.
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Survey of continuing care for cardiacs in Czech Republic, with focus on nursing care.
DOLEŽEL, Jakub
Cardiovascular diseases are the leading cause of death in the Czech Republic. An increasing number of its inhabitants become cardiac patients who require a nursing intervention. Nursing in cardiology has an irreplaceable position in the cardiovascular care provision. The health care costs are rising, nursing has been undergoing many changes. Training of cardiology nurses gets changed, as well as the image and role of cardiology nurses in society. Cardiology nurses are much more independent, educated and organized. In cardiovascular facilities nursing care is being standardized and the quality of care is improving. In this thesis, focus is given to nursing in cardiology. In the introduction the issue of cardiovascular diseases is outlined, the major part is devoted to the concept of Czech nursing in cardiology. Individual stages of the system of care for cardiac patients in the Czech Republic and the status of cardiology nurses involved in the system are surveyed. Attention is also paid to the structure of cardiovascular facilities and expert companies in our country and abroad. The thesis has the title: Survey of continuity of care for cardiac patients in the Czech Republic with focus on nursing care. In total five goals, seven research questions and four hypotheses were stated. We surveyed the cardiology nurses´ attitude to lifelong learning, if they are building their own specific image, and if they ensure the continuity of care. Our objective was also to identify the role of nurses in education of cardiac patients and the level of cardiac patients´ knowledge. The research section is elaborated on the basis of a qualitative and quantitative investigation. The qualitative part was carried out by semi-structured interviews with cardiology nurses working in comprehensive cardiovascular centers. The quantitative part of the survey was conducted with patients of comprehensive cardiovascular centers. Seventy domestic and foreign sources of literature devoted not only to the issueof cardiovascular diseases were quoted. The research results are supposed to serve as a basis for coordinated efforts of all participating nurses and institutions to build a well-functioning and technically and economically efficient system of nursing care for cardiac patients in CR.
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Age management
Jirásková, Barbora ; Dvořák, Marek (advisor)
This thesis processes the concept of the human resources management with respect to the age structure of employees in the intentions of the Czech Republic. In the theoretical part, there is outlined the history of the application of the principle of age management, focusing on current demographic trends, forecasts of population age structure, the aging workforce and the need to preserve the ability to work into old age. Points to the need to adapt corporate strategy, personnel management trend of an aging population. It presents ideas for the main underlying programs and legislative measures which form the basis of the latest concepts and strategic plans in the Czech Republic and Europe. The empirical part deals with a specific level of allowance organization established by TSU and two sub investigation. The first is a case study of age management staff. The resulting data are confronted with the results of a survey among employees of the organization. The second investigation are interviews with members of management and employees of the HR department on the issue of the introduction of age management, their awareness of the concept of age management, the question of age discrimination, the issue of maintaining the continuity of knowledge in the organization and their views on these topics. The outcome of this survey indicates a willingness and readiness of the organization has already received age management principles adhere to and develop further.
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Lifelong Education as a Part of the Social System
Neckařová, Jana ; Šrédl, Karel (advisor) ; Hana, Hana (referee)
The diploma thesis discusses about education of adult population, while pointing out necessity of education in any age. This thesis explain importance of education of the adult population, mention forms and possible methods which are used in this type of education the most. Besides the theoretical outcome there is practical aspect included as well in form of questionnaires. Investigation in form of research was focused directly on employees, who as well as on employers whose employees attended the program. In summary both parties consider adulthood gained knowledge as a great benefit to employee as well as employer. In any case, people with higher level of education have better chances of getting a possible job than those with no or low level of education.
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Erosion protection of slopes from assignment to implementation
Konopecká, Vladislava ; Janeček, Miloslav (advisor) ; Kalibová, Jana (referee)
The thesis is following up on the findings to the issues presented in the Bachelor's thesis, where they were described mainly the methods and materials used to secure the slopes of pipeline, will address not only the final solution method of protection against erosion of the slopes, but in particular all conditioning influences such as the topography, the type and quality of rock and soil in the area of the building, surrounding buildings, and last but not least property relations that can significantly affect the design solution in terms of difficulty of implementation, durability, aesthetics and economic performance of the resulting construction works. Alpha-Omega of the initial phase is the analysis and the interdependence of the issues just for land consolidation, anti-erosion measures, construction procedures in accordance with the geology of the chosen territory and the intended realization of the construction project. The evaluation of the risks associated with this issue on the basis of field investigation, examination with a valid legal legislation, SWOT analysis will be ended.
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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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Microbiota of the digestive tract of bees and related insect and the influencing facftors
Hroncová, Zuzana ; Havlík, Jaroslav (advisor) ; Kalous, Lukáš (referee)
This thesis consists of six research chapters, out of which, five have already been published in research journals, 1 is in the process of submission and the last chapter presents original unpublished confidential data in the process of manuscript preparation.
The research presented in this thesis concerns the complex mechanisms of bees and wasps immune system focused on microbiota as component of immunity. As shown in the introduction, highly social and managed species of bees like honey bees and bumble bees, play key roles in natural and agricultural ecosystems worldwide. Recent losses of bees have been attributed to pesticide exposure, poor nutrition, increased parasite loads and habitat degradation. Over the past several years, governments, beekeepers, and the general public worldwide have become concerned by increased losses of honey bee colonies, calling for more research on how to keep colonies healthy. Our main aim was to explore the complex mechanisms of bees and related species gut bacterial populations, their links to insect immunity and investigate the opportunities for an intervention. Part of our aim was to characterise the bumble bee and wasp gut microbiota using 16S RNA sequencing in a search for potentially novel bacterial species.
We have tried to explain how microbiome interacts with the host and showed that major members of these communities appear to benefit the host. The simple gut communities of social bees present ideal model systems to investigate the underlying evolutionary and genetic processes of such interactions. Information based on our results may help in the design of proper probiotic supplementation strategies with respect to physiological conditions in the honey bee gut.
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Individual human odor as a forensic trail in criminal proceeding made by contact or contactless transmission and its resistance to physical agents
Santariová, Milena ; Bartoš, Luděk (advisor) ; Chmelíková, Eva (referee)
The dissertation thesis consists of four papers that have been published in scientific journals.
Study n. 1
The need to recover evidence from water is quite common in criminal investigation. The article deals with the possibility to collect human scent from such objects and with the ability of specially trained dogs to match such scent samples with scent samples collected from detained suspects. During an experiment, designed as a blind one, it has been proved, that human scent can survive on submerged objects and can be later used for scent identification.
Study n. 2
To collect odors the Czech Republic Police use special fabric sorbents manufactured under the registered mark ARATEX. Before use the fabric sorbent is treated by water vapor sterilization. After the scent identification the sorbent is destroyed. The goal of the study was to verify if the vapor sterilization is effective enough to remove human scent that has already penetrated into the sorbent structure or in other words if the sorbent can be exposed to vapor sterilization and then used again. Specially trained dogs were used to match starting odors with target odors in the line-ups. The results showed that dogs are able to correctly match human odors even after they have being exposed to vapor sterilization.
Study n. 3
The purpose of the study was to determine the temperature at which the human scent is degraded so that a dog would not be able to identify it. In contrast to expectations, eight dogs used in the experiment almost flawlessly identified human scents from five scent donors exposed to temperatures of 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, and 800°C. Only two of the dogs were able to identify 5 of 15 scent samples exposed to 900°C. No dog identified a scent exposed to 1000°C. Our study verified heat survivability of human scent far beyond existing expectations.
Study n. 4
We tested the hypothesis that if odor fallout (the release of a human odor onto an untouched object) in human subjects exists, then holding a hand above an absorbent will produce a detectable scent which will be subsequently matched in a detection test by trained dogs. Scents were collected from seven males to sterile cotton absorbent squares. The left hand was used to get the control scent and the right hand served as the target scent. Each experimental subject was sitting and his left hand was laid down on a cotton square for 3 min. The right hand was held 5 cm above another cotton square for 3 min. The scent identification was done by two specially trained police German shepherds. Both dogs performed 14 line-ups and correctly matched the collected scents of all test subjects. The results suggest the existence of human odor fallout, whereby a human scent trace is left by humans even if they do not touch an object.
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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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New Methods for Increasing Efficiency and Speed of Functional Verification
Zachariášová, Marcela ; Dohnal, Jan (referee) ; Steininger, Andreas (referee) ; Kotásek, Zdeněk (advisor)
Při vývoji současných číslicových systémů, např. vestavěných systému a počítačového hardware, je nutné hledat postupy, jak zvýšit jejich spolehlivost. Jednou z možností je zvyšování efektivity a rychlosti verifikačních procesů, které se provádějí v raných fázích návrhu. V této dizertační práci se pozornost věnuje verifikačnímu přístupu s názvem funkční verifikace. Je identifikováno několik výzev a problému týkajících se efektivity a rychlosti funkční verifikace a ty jsou následně řešeny v cílech dizertační práce. První cíl se zaměřuje na redukci simulačního času v průběhu verifikace komplexních systémů. Důvodem je, že simulace inherentně paralelního hardwarového systému trvá velmi dlouho v porovnání s během v skutečném hardware. Je proto navrhnuta optimalizační technika, která umisťuje verifikovaný systém do FPGA akcelerátoru, zatím co část verifikačního prostředí stále běží v simulaci. Tímto přemístěním je možné výrazně zredukovat simulační režii. Druhý cíl se zabývá ručně připravovanými verifikačními prostředími, která představují výrazné omezení ve verifikační produktivitě. Tato režie však není nutná, protože většina verifikačních prostředí má velice podobnou strukturu, jelikož využívají komponenty standardních verifikačních metodik. Tyto komponenty se jen upravují s ohledem na verifikovaný systém. Proto druhá optimalizační technika analyzuje popis systému na vyšší úrovni abstrakce a automatizuje tvorbu verifikačních prostředí tím, že je automaticky generuje z tohoto vysoko-úrovňového popisu. Třetí cíl zkoumá, jak je možné docílit úplnost verifikace pomocí inteligentní automatizace. Úplnost verifikace se typicky měří pomocí různých metrik pokrytí a verifikace je ukončena, když je dosažena právě vysoká úroveň pokrytí. Proto je navržena třetí optimalizační technika, která řídí generování vstupů pro verifikovaný systém tak, aby tyto vstupy aktivovali současně co nejvíc bodů pokrytí a aby byla rychlost konvergence k maximálnímu pokrytí co nejvyšší. Jako hlavní optimalizační prostředek se používá genetický algoritmus, který je přizpůsoben pro funkční verifikaci a jeho parametry jsou vyladěny pro tuto doménu. Běží na pozadí verifikačního procesu, analyzuje dosažené pokrytí a na základě toho dynamicky upravuje omezující podmínky pro generátor vstupů. Tyto podmínky jsou reprezentovány pravděpodobnostmi, které určují výběr vhodných hodnot ze vstupní domény. Čtvrtý cíl diskutuje, zda je možné znovu použít vstupy z funkční verifikace pro účely regresního testování a optimalizovat je tak, aby byla rychlost testování co nejvyšší. Ve funkční verifikaci je totiž běžné, že vstupy jsou značně redundantní, jelikož jsou produkovány generátorem. Pro regresní testy ale tato redundance není potřebná a proto může být eliminována. Zároveň je ale nutné dbát na to, aby úroveň pokrytí dosáhnutá optimalizovanou sadou byla stejná, jako u té původní. Čtvrtá optimalizační technika toto reflektuje a opět používá genetický algoritmus jako optimalizační prostředek. Tentokrát ale není integrován do procesu verifikace, ale je použit až po její ukončení. Velmi rychle odstraňuje redundanci z původní sady vstupů a výsledná doba simulace je tak značně optimalizována.
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