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Mechanochemical Preparation of Alumina-Ceria
Jirátová, Květa ; Spojakina, A. ; Tyuliev, G. ; Balabánová, Jana ; Kaluža, Luděk ; Palcheva, R.
Ceria containing catalysts play an essential role in heterogeneous catalytic processes. However, ceria shows poor thermal stability and low specific surface area and therefore, many studies have been done to improve its properties by combination with other oxides. Alumina-ceria is substantial component of the three ways catalysts, due to the ceria ability to function as the buffer of oxygen and to enhance the oxygen storage capacity of the catalysts. Ceria in these catalysts also functions as structural promoting component, increasing alumina stability towards thermal sintering. Promising method of oxides preparation, very interesting and simple but not sufficiently studied yet is a mechanochemical synthesis. Here we report on the synthesis of nano-sized alumina, ceria and ceria-alumina of various compositions by a wet solid phase mechanochemical reaction of hydrous aluminum, and/or cerium nitrate with ammonium bicarbonate after addition of a small amount of water. The aim of this contribution is to study processes being in progress during synthesis of the mixed oxides, interaction between components and their mutual effect on the properties of resulting products. The phase evolution during mechanical milling and the subsequent heat treatment of precursors were studied by X-ray diffraction, DTA/TG, H2-TPR, NH3-TPD, CO2-TPD, N2 adsorption at -195°C, IR, and XPS spectroscopy. Alumina and mixtures of alumina with different quantities of CeO2 (1- 18 wt. %) were synthesized by mechanochemical method from aluminum nitrate, cerium nitrate and ammonia bicarbonate.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22015083108560 - PDF
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Human and social capital in primary education
KOKŠTEIN, Jiří
The thesis contains a theoretical insight into the studies that the issue of human and social capital involved from different perspectives, engage their evolution over time, their measurability, examine them, and complemented with other evidence. This part contains relation of human and social capital in relation to the aging of the human population and focuses on the human capital of older workers. Theoretical study ends with an insight into the basic education, the role of teacher and seeks to provide information on surveys already conducted in the area of education, which in the application of serve for me compared to the data obtained from the survey. The application part is focused on the teaching staff of primary schools. Education in currently globalized world, changing not only its content but also methods and forms of work. Irreplaceable role in this process is played by educators. To meet all the demands placed on them, it is essential that they pay close attention to their continuing education and sharing of acquired education, which is essential to the growth of human and social capital, because they are interacting. The work examines selected sample of teachers and approaches to this issue by detecting what is education motivates them whether they are satisfied with the benefits of educational events, what type of education they prefer etc. Working findings further analyzes looking for relationships between age and sex educators according to the hypotheses . Educator is someone who is in constant contact with other people. This of course also formalizes its attitudes and experiences. As a human being perceives the views of society and shapes on her own views, which it subsequently may influence the exercise of his profession. Therefore, in this part of the thesis is dedicated to exploring and bridging social capital, which determines the size of the circle of people with whom the teachers generally meet and interact. The last research that is possible to find thesis, it is perceptions of social status of teachers by themselves.
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Role of opinion former in Marketing communication
SPRINGEROVÁ, Nikol
This thesis is based on role of opinion former in marketing communication. For this work is chosen professional sphere, concretely the work of dentists in Benešov city. In theoretical part of this thesis are explained terms related with this theme. In practical part is analyzed a current state of view of dentist and public by using quantitative and qualitative methods. Goal of this thesis is draft recomandation of changes in marketing communication together with using a view of opinion former, which should lead to improve this communication.
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Distribution of CD46 and β1 integrin molecules with respect to different membrane structures of the sperm head
Šebková, Nataša ; Frolíková, Michaela ; Děd, Lukáš ; Dvořáková-Hortová, Kateřina
CD46 protein plays an important role during fertilization and its role is associated with acrosome stability. CD46 is probably involved in signalling pathways triggering the acrosome reaction (AR). It also associates through membrane integrins with specific MAP kinases involved in the AR. Our aim was to monitor the dynamics of relocation of CD46 and β1 integrin during sperm maturation and its preparation for the fertilization. The dependence of this localization changes on the dynamic of actin cytoskeleton was studied. Our results show the changes in the localization of these proteins associated with the AR and their co-localization was observed using proximity ligation assay. After the AR CD46 and β1 integrin spreads across the sperm head, entering the post-acrosomal compartment, and permeates the borders of different domains. It was shown previously that actin dynamics is necessary for acrosome reaction-associated translocation of Izumo1 protein that is required for sperm-egg fusion. Therefore Latrunculin A was used during sperm incubation. The co-incubation of capacitated sperm with Latrunculin A leads to a decrease of the percentages of sperm, which express relocation pattern after induced AR. 3D models and visualizations of potential membrane processes responsible for the relocation of proteins from the acrosomal area to the other compartments of the sperm head were prepared. Our results deliver new information that proteins CD46 and β1 integrin undergo dynamic relocation towards the sites of sperm-egg fusion during the AR in vitro. The inhibitor of actin dynamics abrogates significantly the AR-associated changes in proteins localization. We speculate that this relocation is of importance for the successful sperm-egg interaction, adhesion and subsequent gamete fusion.
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Expression of selected proteins in sperm in men with normal and pathological spermiograms using monoclonal antibodies
Pěknicová, Jana ; Čapková, Jana ; Dorosh, Andriy ; Margaryan, Hasmik ; Kubátová, Alena ; Děd, Lukáš
Recent studies show that infertility in human populations it affects an estimated 15% of couples of reproductive age. Male infertility is the primary cause for 60% of these cases. For these reasons, we analyzed the acrosomal and sperm surface proteins in men with normal and pathological spermiograms. We found that intra-acrosome proteins: TERA (Transitional endoplasmic reticulum ATPase), GAPDHS (Sperm Glyceraldehyde-3-phosphate dehydrogenase), and PRKAR2A (C-AMP-dependent protein kinase II, PRKAR2A), which can be identified using our monoclonal antibodies, are different express in healthy men and men with astenozoospermia (with reduced sperm motility), and with a significantly reduced expression in the astenozoospermia. These proteins are involved in energy metabolism and apoptosis of the cells, and some of them in the sperm-egg interaction; therefore, they have an important role in reproduction. On the other hand, there were no statistically significant differences in the expression of surface proteins (Appolipoprotein J (Clusterin) and Semenogelin). Our findings show that astenozoospermia as a complex disorder of the semen is often combined with other pathological conditions that are not diagnosed by the semen analysis. Therefore monoclonal antibodies are so suitable instrument for the detection of proteins associated with the pathology of the sperm in the semen with low sperm motility. In general, monoclonal antibodies against the sperm proteins are an appropriate tool to detect sperm quality in reproductive medicine.
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Estrogen receptor beta (ERβ) in testicular cells and sperm
Dostálová, Pavla ; Žatecká, Eva ; Děd, Lukáš ; Dorosh, Andriy ; Postlerová, Pavla ; Jonáková, Věra ; Dvořáková-Hortová, Kateřina ; Pěknicová, Jana
Estrogen is a steroid hormone that plays an important role during sperm development in the male and female reproductive tract. Estrogen signalling is a complex process that depends on cell milieu and presence of receptors. Thanks to the steroid nature of estrogens, they can pass through the plasmatic membrane and bind to the intracellular estrogen receptors (ERs). Within the cell, there are several pools of ERs. One of them is localized to the cell nucleus and their activation leads to direct or indirect binding to DNA and ultimately to alternation in gene expression (genomic pathway). Other pools of ERs are associated with plasma membrane or are located in cytosol. Activation of membrane associated ERs leads to rapid non-genomic responses. Nowadays, two classical estrogen receptors are known – ERα and ERβ. Since ERβ is a predominant variant in testes, we focused our study on expression of ERβ variants in murine testes and sperm. We detected two variants of ERβ at mRNA level in both, testes and sperm. These variants differ in 54 nucleotids within the ligand binding domain and this variability results in different affinity to estrogen. We analyzed individual testicular cell types (spermatogonia, spermatocytes, spermatids, Sertoli cells) by RT-qPCR. Our results suggest that both ERβ variants are coexpressed in the same cell type and may therefore interact together. This may have consequences in mediating of estrogen signalling. Moreover, ERβ is expressed more in the later stages of spermatogenesis suggesting the role of ERβ in these stages or alternatively in spermatozoa alone. At the protein level, we detected ERβ in nuclear, membrane and cytosolic fraction prepared from testicular tissue suggesting the involvement of both, genomic and non-genomic, pathways of estrogen signaling in testes. In sperm, anti-ERβ antibodies localized ERβ in acrosome region and tail which is in accordance with the known role of estrogen on capacitation, acrosome reaction and motility.
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Possible role of spermatogenic protein glyceraldehyde-3-phosphate dehydrogenase (GAPDHS) in mammalian sperm
Margaryan, Hasmik ; Dorosh, Andriy ; Čapková, Jana ; Postlerová, Pavla ; Philimonenko, Anatoly ; Hozák, Pavel ; Pěknicová, Jana
Sperm proteins are important for the structure and function of these specific, highly differentiated cells. Certain of these proteins play a role in sperm-egg recognition during primary or secondary binding at zona pellucida glycoprotein matrix. The aim of this study was to characterize the acrosomal sperm protein recognized by a monoclonal antibody (MoAb) Hs-8, prepared in our laboratory by immunization of BALB/c mice with human ejaculated sperm, and to test the possible role of this protein in gamete interaction. MoAb Hs-8 specifically labelled a 45 kDa protein from the sperm extract in the immunoblotting test. Sequence analysis identified this Hs-8 protein as GAPDHS. In order to perform a control tests, a commercial mouse anti-GAPDHS MoAb was applied. Both antibodies showed similar staining patterns using immunofluorescence labelling, transmission electron microscopy and immunoblot analysis. Moreover, both Hs-8 and commercial anti-GAPDHS antibodies blocked the secondary sperm-zona pellucida binding. Generally, GAPDHS was considered mainly as sperm-specific glycolytic enzyme involved in energy production during spermatogenesis and sperm motility and its role in the sperm head was unknown. In this study, we confirmed the potential additional role of GAPDHS as a binding protein that is involved in the sperm-zona pellucida interaction.
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CD46 and β1integrin interaction in mouse sperm head
Šebková, Nataša ; Frolíková, Michaela ; Dvořáková-Hortová, Kateřina
CD46 protein plays an important role during fertilization and its role is associated with acrosome stability. CD46 is probably involved in signalling pathways triggering the acrosome reaction. Integrins interact with many cytoskeletal proteins such as actin, therefore changes in the actin cytoskeleton before and after AR may lead to changes in the association and localization of CD46 and β1integrin. Our aim was to monitor mutual CD46 and β1integrin interaction detected by the proximity ligation assay. It generates a localized signal in a form of spots revealing the exact position of the recognition event. Proteins interaction was study in freshly released sperm and sperm during the acrosome reaction, during which there is a gradual relocation of these proteins towards the equatorial segment and the whole sperm head. Proteins α and β tubulin were used as a positive control, α tubulin and β1 integrin as a negative control. In situ PLA showed a distinct spotted signal indicating the mutual interaction of CD46 and β1integrin. A positive response was demonstrated not only in freshly released sperm but also in sperm during the acrosome reaction. Freshly released sperm were distinctively labelled in the acrosome region and the neck, similarly to the positive control. Sperm during the acrosome reaction showed the signal across the whole sperm head region. No signal or sporadic nonspecific staining was detected in the case of the negative control. In summary, our results deliver new information that proteins CD46 and β1 integrin interact with each other. These results suppose the theory that β1 integrin can mediate a connection between CD46 and sperm cytoskeleton thereby molecules of signalling pathways leading to activation of the acrosome reaction.
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Fluorescent analysis of the differential protein expression in normozoospermic and asthenozoospermic sperm samples
Děd, Lukáš ; Čapková, Jana ; Kubátová, Alena ; Teplá, O. ; Pěknicová, Jana
Asthenozoospermia is one of the main seminal pathologies underlying male infertility. Previous proteomic studies have demonstrated the significant differences in the protein profiles between normozoospermic and asthenozoospermic sperm samples. Since these studies were primarily focused on the identification of differentially expressed proteins by mass spectrometry, we aimed to evaluate the ability of our diagnostic antibodies to detect the differential expression of selected protein markers by fluorescent microscopy and flow cytometry techniques. Therefore, we analyzed sperm samples from 30 men with normal and 30 men with astheno spermiograms, average by the panel of our diagnostic anti-human sperm (Hs) antibodies. Fluorescent microscopy and flow cytometry analysis revealed quantitative differences in the protein abundances between normo and astheno sperm samples, namely, in GAPDHs, evaluated with Hs-8 MoAb, VCP, evaluated with Hs-14 MoAb, and ATP synthase, evaluated with MoAb Hs-36. From the methodological point of view, we observed very high correlation between the data obtained by fluorescent microscopy and flow cytometry techniques and therefore both methods are useful for evaluation of protein differences associated with asthenozoospermia. From the clinical point of view, we observed the strong association of the low sperm motility in the sample with the expression of proteins, playing an important role in sperm energy metabolism (expected), but also with the expression of all tested intra-acrosomal proteins. These findings further demonstrate asthenozoospermia as a complex semen disorder frequently associated with other semen pathologies, which are not diagnosed by basic semen analysis, and the possibility to use monoclonal antibodies as a tool for diagnosis of protein associated sperm pathologies in the semen with the low sperm motility.
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The role of a nurse in a prevention and a treatment of intestinal parasites of children
JANDOVÁ, Anna
The best-known intestinal parasites are Pinworms, Roundworms, Tapeworms and the disease called Toxocarosis. The oftenest parasite is, according to sources, the Pinworm. Intestinal parasites affect mostly young children of pre-school age, sometimes even older. The first goal of the thesis was to investigate parents' awareness of the prevention of parasitic diseases in children. There is a hypothesis set to this goal: Parents of children who suffered from parasitic disease are more informed than parents of children who have not had this disease. The second goal was to map the specifics of nursing care for children with parasitic diseases at GPCHA practice. A research question was chosen for this aim: What are the specifics of nursing care at GPCHA in parasitic diseases? In methodology, the empirical part was chosen and it was a qualitative - quantitative research survey. For the quantitative part, the interrogation method and technique of non-standardized questionnaire was used. The research sample of quantitative survey consisted of 223 respondents, it means parents whose child is aged from 0 to 6 years. The questionnaires were distributed on social networking and others in a nursery school in Týn nad Vltavou. At the very beginning, respondents were acquainted with the topic of the thesis. The results of a quantitative survey were processed with the help of a data matrix and were further processed within twenty-arranged bar charts. To verify the hypothesis, we used the Chi- Quadrat test, which in this case is not satisfactory, therefore, there had to be chosen to merge the responses. An interrogation method, technique-depth interview was used in the qualitative part. The research group consisted of five nurses; three nurses working at GPCHA in Týn nad Vltavou and two working at GPCHA in České Budějovice. While processing the interviews, there open coding was used and an analysis of interviews was conducted by using the method of Pencil and Paper Interview. The results of this bachelor thesis will be published in the journal Paediatrics practice.
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