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Factors influencing changes to the content of antioxidants in the body.
MERLEOVÁ, Gabriela
This thesis deals with the relationship between antioxidants and free radicals, their interactions and effects on the human body. Characteristics, properties and occurrence of some antioxidants such as carotenoids, flavonoids, ascorbic acid, selenium, melatonin, quercetin, etc., may explain some of the mechanisms of their effects on human health, particularly in the area of lifestyle diseases such as cardiovascular disease, cancer and obesity. Fruits and vegetables are important sources of dietary antioxidants and therefore are regularly added to the diet part of the antioxidant defense of the organism, although the content of antioxidants in these foods may be changed by external influences. Information used in this study were obtained from the scientific and professional publications and periodicals found in domestic and international databases of scientific and specialist literature.
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Dynamic model of human resources in project management
Hančar, Michal ; Mildeová, Stanislava (advisor) ; Šviráková, Eva (referee)
This thesis is focused on dynamics of soft factors influencing workers during projects. These factors include motivation, workplace atmosphere, team synergy of workers and their emotions, and attribute of project manager who manages the project. Identification of soft factors and their relationships was achieved by examination of scientific literature in psychology and system dynamics. Description of managing project matters was achieved by examination of scientific literature dealing with project management. The main objective of this thesis is to create a dynamic model which simulates behavior of these soft factors influencing the project staff. The primary metric of the model is efficiency of workers participating on the project based on input parameters. Validation of the model was achieved by verification of historic behavior of key elements. Results of validation experiments correspond with historic behavior with roughly 95 % accuracy. At the end of this thesis is presented an ICT project case study. Based on the results of simulation experiments is performed a scenario analysis which tries to bring possible suggestions for project management.
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Optimal production strategy of the chosen company in the area of mechanical engineering
Brachtlová, Veronika ; Průša, Přemysl (advisor) ; Všetečková, Dana (referee)
The topic of this diploma thesis is "Optimal production strategy of the chosen company in the area of mechanical engineering" - namely the EUTECH join stock company, or more precisely its toolshop division, which deals with the manufacture of injection moulds, parts and production of special devices for aircraft industry. The aim of the paper is to evaluate, according to the defined factors, what is for the EUTECH join stock company more favourable - invest in purchase of the 5-Axis CNC machining center technology and deal with this process inside of the company or ensure this technology in cooperation with another companies. The thesis is divided into two main parts - theoretical and practical. In the theoretical part, the subjects of operation management theory and production are dealt with. The practical part deals with the production strategy of the EUTECH join stock company, or more precisely of its toolshop division in detail. The company is briefly introduced, the situational analysis of division toolshop is conducted and the production process of the company is examined. The final chapter deals with the use of cooperation in the toolshop division. The main and other factors affecting the choice of "product or sell" strategy are evaluated and consequently is decided which strategy is in case of the 5-Axis CNC machining center technology more favourable.
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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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Political and social aspects of local government - public participation in the municipality affairs
Kučerová, Zuzana ; Kopřiva, Radek (advisor) ; Lenka, Lenka (referee)
The thesis deals with contemporary theories of the citizens involvement in municipal life and civic society. It works with Nekol s concept which is a typology of forms of participation. The aim of the thesis is to test the usefulness of this concept on two selected municipalities in the Czech Republic Týnec nad Labem and Krakovany.
The thesis focuses mainly of the description of participation forms and it examines the factors which influence the differences in people s participation. It shows that Nekol s concept is a useful tool in the effort to understand these differences in the two selected municipalities. The decisive distinguishing aspect is the stability of political environment. In Krakovany, the political environment is settled and is connected with the mayor, who is an important initiator of development in the town.
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Political aspects of local goverment. Elections and electoral behavior of citizens in the town of Nový Bydžov
Bieliková, Eva ; Kopřiva, Radek (advisor) ; Lenka, Lenka (referee)
The thesis addresses the issue of elections and electoral behavior of citizens in the town of Nový Bydžov. It is focused on assessment of factors that influence voting behavior of citizens in the town of Nový Bydžov. It describes the evolution of electoral behavior from 1994 to 2014 and verification of the applicability of the theory of electoral behavior for explanation of the electoral decision-making of the electorate in Nový Bydžov. The theoretical part addresses (describes) theoretical definition of areas that relate to the topic of the thesis. The practical part is a case study of Nový Bydžov. Subject of study is the town of Nový Bydžov, objects of study are the voters participating in the elections to the council of this city. To achieve the set goals (objectives) is recovered content of documents study (written records), a questionnaire survey, comparative methods and synthesis.
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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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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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FRACTURE MECHANICS ASSESSMENT OF CRACKED WELDED POLYOLEFIN PIPES
Mikula, Jakub ; Ševčík, Martin ; Hutař, Pavel ; Náhlík, Luboš
The aim of this paper is to present methodology for estimation of fracture mechanics parameters in polyolefin pipes with an axially oriented crack using three dimensional numerical analyses. Linear elastic fracture mechanics is used for description of fracture behavior. In the paper, three different variants of pipe weld with an internal axial semi-elliptical crack are studied. Numerical models correspond to a cracked pipe containing material nonhomogeneity in the welding area caused by welding process. A critical locations of the crack initiated along the pipe wall is found and the stress intensity factor for such cracks with real crack shape are numerically estimated in these critical locations. The methodology presented here can be used for estimation of residual lifetime of welded polymer pipes containing crack.
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The Use of the Addictive Drugs by the Seniors
KOPAČKOVÁ, Dominika
The bachelor thesis deals with using addictive substances by senior citizens. The age cathegoty 60+ should not be omitted when speaking of using addictive substances. Even senior citizens are users of some addictive substances, especially drugs. The thesis is divided into two parts, theoretical and explorative one. There are four chapters in the theoretical part (Old age and ageing, Substance addiction, Addictive substances and their classification, Usage of addictive substances in the old age) and summarizes the knowledge from recent literature about this topic. First, the old age and ageing are described. This chapter deals with ageing and old age of the human. This work describes the right mental hygiene, too. Multi-factorial manifestation of the old age (biological, psychological and social) is mentioned as well. In the second chapter there are described the factors that increase probability of the addiction origin. These factors can be genetic, biological, and psychological. There are mentioned some system models of the formation, development and maintenance of addiction, dependence and definition of the signs that addiction manifests. The third chapter divides addictive substances between legal and illegal. There are their effects, impacts on the human organism decribed. The group of legal addictive substances are included tobacco, alcohol, drugs and certain foods. Illegal substances represented here by cannabis, hallucinogens, stimulants, opiates. The last fourth chapter focuses directly on the addictive behaviour of the senior citizens. Seniors are also users of substances with addictive potential. At first alcoholism is mapped, other chapters devote addiction to nicotine, drugs and narcotics. The main goal of the thesis is to determine whether seniors use an addictive substance. A partial goal of is to find out the extent and cause of using addictive substances by the senior population. To find out these goals there were used the principles of quantitive research. To collect the data there were used questionnaires, created all by the author. The questionnaires were created with open and closed questiones and used in the printed form. The research has been conducted in Sušice and its close surroundings in February 2015. Respondents were the people with the least age limit of 70 years. These were 40 people living in their households or home for elderly. The results show that also amongst senior citizens can be found those ones who use the addictive substances. Current problem are by the doctor prescribed drugs. Today´s senior citizen uses drugs regularly, very often also combination of more drugs. Seniors often use medication to relieve the pain because the pain occurs more frequently. They use drugs to help them sleep better, too. The next group of addictive substances, which this chapter deals with, are drugs with a shoothing effect. There are smokers between the senior citizens who bare this bad habit from their midlife. Some research shows that cannabis helps people with Parkinson's and Alzheimer´s disease. Seniors do not use cannabis for these purposes because it is not legal. Alcohol is drunk by older people on occassion, on the other hand there are also people who drink such an amount that is not considered as not-risky. Seniors do not drink so much on one occasion, compared to the young generation. In the thesis this problem is described more detailed. Results of the research can be used by lay public to understand issues of addictive substances better. This thesis can be source of information for students of healt-social fields of study and it can improve the awareness about reasons of using addictive substances amongs senior citizens.
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