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Stress in the workplace - the possibility of prevention (the report of a qualitative research - focus groups)
Tabery, Paulína
This report presents the outcomes of a qualitative research about the extent of stress among em-ployees in the Czech Republic.

Measurement and evaluation of pulsating water jet peening intensity
Hlaváček, Petr ; Klich, Jiří ; Foldyna, Josef ; Sitek, Libor
Pulsating water jet peening is a promising method in surface treatment. It has the potential to induce compressive residual stresses that benefit the fatigue life of components similar to the other peening process. In this paper experimental results obtained by action of pulsating water jet on Almen strips are presented.
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Porovnání cyklických deformačních křivek materiálu ADI
Zapletal, J. ; Obrtlík, Karel ; Věchet, S.
Stress-strain response of austempered ductile iron was studied in tensile and in fatigue loading. Cyclic stress-strain curve was obtained both in the companion specimen method and in the multiple step test method. Both cyclic stress-strain curves lie above the monotonic curve.

Molecular factors of artherogenesis in chronic kidney disease with experimental model of chronic inhibition of Nitric Oxide Synthesis and its Effect of HMG-CoA reductase inhibitoin
Lecian, Dalibor ; Matouš, Bohuslav (advisor) ; Tesař, Vladimír (referee) ; Zadražil, Josef (referee)
The experimental part of the thesis covered the markers involved in nitric oxide deficiency model in rats. The analogue of arginine N-nitro- L -arginine-methyl ester ( L -NAME) was used. L -NAME administration resulted in sustained elevation of BP, decreased GFR, and in higher albuminuria compared to control animals. The administration of hypolipidemic drug - atorvastatin to Wistar rats was studied. The statin used caused lower albuminuria and prevented decreases in GFR in L -NAME rats without having an impact on hypertension. CAV1 protein expression was similar in all groups of rats. In contrast, VEGF expression and RhoA activity was increased in L -NAME-treated animals, and normalized with coadministration of atorvastatin. Clinical part of the thesis focused on the analysis of markers of oxidative stress in obese and non-obese patients with CKD and after kidney transplantation. The patients with CKD had elevated serum concentrations of AGEs, sRAGE and ADMA with the maximal concentrations of AGEs in the patients on hemodialysis. The successful kidney transplantation decreases the AGEs, sRAGE and ADMA concentrations but not to normal value according to general population. Patients with obesity exhibited lower concentrations of sRAGE in CKD as a protective factor for cardiovascular disease. Concentrations of...

The influence of stress and life satisfaction of chronic vulvovaginal candidiasis
Hájková, Lucie ; Jílek, Petr (advisor) ; Kestřánek, Jan (referee)
1 SUMMARY In this study we are dealing with the effect of stress and life satisfaction on recurrent vulvovaginal candidiasis (RVVC). Vulvovaginal candidiasis (VVC) is one of the most frequent genital infections. It is hypothesized that 75% of women experience during their reproductive age at least 1 episode of VVC in their lifetime. RVVC can be defined as four or more attacks of symptomatic vulvovaginal candidiasis in 12 month period. The true incidence of RVVC remains unknown. Estimates over many years suggest that the incidence is approximately 5%; another recent study shows that the incidence is approximately 8% of women during their reproductive age. Our previous study suggests that the incidence is approximately 7.6%. There were elaborate questionnaires, including a questionnaire on life satisfaction and the level of vulnerability by stress, made for the purpose of this study. Each questionnaire consists of 17 pages and includes 49 questions. Full text of the questionnaire is showed in enclosure. The questionnaire consisted of 15 questions in the bold frames that were tailor-made just for women, who have repeatedly experienced episodes of vulvovaginal candidiasis. A sample of 199 women was interviewed, 184 of them completed our questionnaire (which is 92.5%). By evaluation of questions in the bold...

Analysis of influence of grindig parameters on the surface integrity with a view to residual stresses
Dömény, Tibor ; Sedlák, Josef (referee) ; Csölle Putzová, Ildikó (advisor)
Since grinding is often the last process of a manufactured part, caution has to be taken in order to ensure the integrity of the surface. The role of grinding induced residual stresses can be important in fatigue or wear resistance. In most cases we cannot evaluate accurately and easily their distribution. On this purpose, many scientists are working on the modeling of grinding and its effects on a many points. The main aim of this work is to analyse of residual stresses influenced by grinding parameters.

Effect of low doses of herbicide paraquat on antioxidant defense in Drosophila
SÁBOVÁ, Michala
Disruption of cell equilibrium between production of free radicals and antioxidant defence is named oxidative stress. The main component of antioxidant mechanism is activity of antioxidant enzymes, which include superoxide dismutase (SOD) and catalase. In this study we evaluated the effect of herbicide paraquat on response of SOD and catalase, their transcription level and locomotion activity in Drosophila melanogaster. We exposed the flies to a wide range of paraquat concentration. Our results revealed that transcript and enzymatic levels of both SOD and catalase have a similar biphasic dose response with the peaks at 2,5 ?M paraquat concentration, resembling hormetic effect. Then, males were more sensitive than females. However, females had an increased locomotion activity. We found that paraquat susceptibility is increased in males and mating flies. Therefore, this study supports hypothesis of stress sensitivity elevation as a physiological cost of reproduction.

Stress load in a specific job
Stožický, František ; Michálek, Pavel (advisor) ; Daniel, Daniel (referee)
Objectives work This thesis will deal with stress and its effects on the activity of driving city mass transit. The work is described how stress is, how it can be managed, and how to prevent it. Empirical part will deal with the effects of stress on the driver's performance and resistance to him. methodics The theoretical part will be based on a compilation of texts from literature. In the empirical part will be used method of standardized questionnaires. For research purposes is determined hypothesis, which will be checked by statistical methods. The results of empirical research will be commented and presented in the summary tables and graphs.

Fatigue strength and life of real structures under combined random loading
Svoboda, Jaroslav ; Fröhlich, Vladislav ; Kraus, V.
An investigation of fatigue strength and life usually joined with experiments, which are made using small testing specimens. This is the reason why majority of numerical methods used for fatigue of materials was derived basing on those experiments under kinds of loading. It is rather difficult to apply these methods for real structures loaded by random combined processes in service. The contribution discusses the problem and shows its complexity on an example.

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.