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Optimization of network flow monitoring
Žádník, Martin ; Lhotka,, Ladislav (referee) ; Matoušek, Radomil (referee) ; Sekanina, Lukáš (advisor)
The thesis deals with optimization of network flow monitoring. Flow-based network traffic processing, that is, processing packets based on some state information associated to the flows which the packets belong to, is a key enabler for a variety of network services and applications. The number of simultaneous flows increases with the growing number of new services and applications. It has become a challenge to keep a state per each flow in a network device processing high speed traffic. A flow table, a structure with flow states, must be stored in a memory hierarchy. The memory closest to the processing is known as a flow cache. Flow cache management plays an important role in terms of its effective utilization, which affects the performance of the whole system. This thesis focuses on an automated design of cache replacement policy optimized to a deployment on particular networks. A genetic algorithm is proposed to automate this process. The genetic algorithm generates and evaluates evolved replacement policies by a simulation on obtained traffic traces. The proposed algorithm is evaluated by designing replacement policies for two variations of the cache management problem. The first variation is an evolution of the replacement policy with an overall low number of state evictions from the flow cache. The second variation represents an evolution of the replacement policy with a low number of evictions belonging to large flows only. Optimized replacement policies for both variations are found while experimenting with various encoding of the replacement policy and genetic operators. The newly evolved replacement policies achieve better results than other tested policies. The evolved replacement policy lowers the overall amount of evictions by ten percent in comparison with the best compared policy. The evolved replacement policy focusing on large flows lowers the amount of their evictions two times. Moreover, no eviction occurs for most of the large flows (over 90%). The evolved replacement policy offers better resilience against flooding the flow cache with large amount of short flows which are typical side effects of scanning or distributed denial of service activities. An extension of the replacement policy is also proposed. The extension complements the replacement policy with an additional information extracted from packet headers. The results show further decrease in the number of evictions when the extension is used.
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Právní a zdravotně sociální aspekty činnosti OSPOD jako ustanovených opatrovníků v zámu nezletilých dětí
BORSKÁ, Jana
The Czech Republic as a signatory of the Convention on the Rights of the Child has vested the practice of state administration in the field of care for minor children to municipalities with extended powers, where the protection of the rights and legitimate interests of minor children is safeguarded by state authorities of social and legal protection of children (ASLPC hereinafter). These authorities are incorporated to the extent laid down by the Act on Social and Legal Protection of Children (Act No 359/1999 Coll., as amended). The position and roles of ASLPC and their competence and jurisdiction are also regulated by the same act. The position of workers of these authorities and its legal embodiment is equally important. Regarding professionality, there are high demands on these workers. In the Czech Republic, significant changes in legislature have been made over the past three years. These amendments have led to the strengthening of the rights of minor children and to the establishing of new tools for their protection. In connection with the adoption of new substantive regulation of family law, which is now exhaustively dealt with by the Act No 89/2012 Coll., the Civil Code, new procedural rules have been established regarding protection of rights of minor children. Such procedural legislation includes (apart from the long-existent Act No. 99/1963, the Code of Civil Procedure) the Act No 292/2013 Coll., on Special Civil Proceedings. The decision-making regarding minor children has been vested mainly by the state into the competence of courts. The courts appoint the locally relevant ASLPC as a guardian who then represents the interests of minor children. The purpose, interwoven with and derived from the first one, was to explore the opinions of selected social workers of ASLPC and of district court judges regarding the defined problems occurring during the work of ASLPCs and courts while protecting the interests of minor children. These particularly include: the use of the tool of precautionary measure; problems of different territorial jurisdiction of courts and ASLPCs; processing of complaints regarding bias in various phases of the proceedings; professional training of workers of ASLPC It is evident from the proposals of both judges and ASLPC workers that it is necessary to unify territorial jurisdiction. The courts are suggesting the priority criterion of the address where the child mainly resides. ASLPC workers suggest the official permanent residence as the prime criterion. Bias causes problems in all phases of proceedings. It is obvious that courts take differing approaches towards the solution of this problem (some courts solve the problem of bias complaints filed by the parties while other courts do not) and for ASLPC workers it is difficult to assess how to act when such complaint is raised against them. The training of ASLPC workers - workers are obliged to educate themselves and their employer is obliged to finance such training. Not all ASLPCs are able to provide training in the required extent - due to financial reasons (the average costs of education of one employee pose from 9,169 to 13,400 CZK annually and they cover approximately 6 days of training). The heavy work-load caused by insufficient numbers of ASLPC employees prevents them from completing such compulsory training. As part of the examination of the "participation of a collision guardian in court proceedings" it has been found out that irregular participation of the worker in the proceedings (absence from participation in appeals proceedings); incomplete reports (directed to courts) from surveys in families. Based on comprehensive examination of the problems of territorial jurisdiction, it was recommended that requests are independently recorded and financial compensation is provided for ASLPCs who are requested to represent minors in front of courts, to draft proposals for precautionary measures.
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Specificity of insect-plant associations and their role in the formation of plant defenses and speciation
VOLF, Martin
The aim of this dissertation is to investigate what role insect-plant interactions play in the formation of host-plant defenses and in the diversification of both groups. We show that various groups of herbivore respond differently to host-plant defenses. Therefore plant defenses diversify into suites of complementary traits, as individual traits fail to provide protection against specialized herbivores. Further, we identify what levels of host-phylogeny shape the food-web structure of insect herbivores. We show that specialized herbivores are affected mainly by the terminal parts of the host-phylogeny. In contrast, more polyphagous guilds are affected mainly by the mid-levels of the host phylogeny because the effects of terminal or deeper phylogeny seem to be surpassed by other factors in more generalist insect species. In the last chapter, we show how specialized insect-plant interactions generated by tight insect-plant coevolution can influence the speciation in plants over environmental gradients.
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Crystallographic study of the iron-regulated outer membrane lipoprotein (FrpD) from Neisseria meningitidis
SVIRIDOVA, Ekaterina
Neisseria meningitidis (N. meningitidis) is a Gram-negative commensal bacterium colonizing nasopharynx of about 10 % of healthy individuals, which can cause invasive diseases, such sepsis and meningitis, upon occasional penetration into bloodstream. Pathogenesis of N. meningitidis appears to be directly related to conditions of limited iron availability. Under these conditions two proteins of unknown function: FrpC and FrpD, are synthesized. FrpD is a highly conserved lipoprotein of N. meningitidis anchored to the bacterial outer membrane. It is known that FrpD tightly binds the FrpC protein, which belongs to the Repeat-in-Toxin (RTX) protein family and may act as bacterial exotoxin. However, the mechanism of FrpD-FrpC interaction and the exact function of this complex are unknown due to the absence of structural information on these proteins. Therefore, we set out to determine the structure of FrpD and provide insights into its interaction mechanism with FrpC and structure-functional relationships of these two proteins. We determined the first crystal and solution structures of the FrpD protein. We found that atomic structures of FrpD reveal a novel protein fold. We uncovered the structure-function relationships underlying the mechanism of interaction between the FrpD and FrpC proteins and tested the putative function of the FrpD-FrpC1-414 complex in vitro. Finally, we proposed the putative function of the FrpD-FrpC1-414 complex as a new minor adhesin of N. meningitidis, which mediates the bacterial adhesion to the host epithelial cells and facilitate the colonization. Our work constitutes the first step in clarifying the molecular basis of the FrpD-FrpC interaction and sets the base for further investigation of the role of FrpD and FrpC in the virulence mechanism of N. meningitidis.
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Role fosforu v biologické aktivitě kryogenních půd
ČAPEK, Petr
The combined effect of temperature, moisture and phosphorus availability on soil organic matter mineralization in permafrost affected soils of northern circumpolar region was investigated. This study was a part of research activities of the European project CryoCARB and it was primarily focused on the cryoturbated organic horizons of permafrost affected soils. During this study, the temperature sensitivity of the organic matter mineralization and its relation to the soil moisture and phosphorus availability was investigated using series of incubation experiments and field measurements.
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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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Characteristics of the working behavior of Czechs and Ukrainians
BYKOVA, Sofia
The aim of this work is to create a transparent and comparable characteristics of the work behavior phenomenon within the cultures of those states - what is common and what is different between them, or maybe incompatible .It is supposed to have some analysis of possible conflicts and their connection with the mentality. The primary reason of this aim choosing is the specialty I study. My work contains information that could be interesting and useful not only for me and my future job, but also for managers and other employees. Overview of examined issues contains specific points, such as the fundamentals of economic psychology and behavioral economics (symbiosis of psychological and economic opinion on motivation and rationality of individuals), theories of motivation and reaction to different occurrence, characteristic of the term "mentality", general points about the human impact of the world economy. For realizing the goals of my work the following hypotheses have been proposed - Czech and Ukrainian mentality have significant differences, though these cultures are close. - Ukrainian and Czech employees are able to work effectively in a team and find a "common language" in the workplace. The difference in mentality does not obstruct on it. - Employers could be interested in the Ukrainian employees taking into account their high concernment and motivation. All three of the hypotheses were confirmed by observed data and comparison of mentality characteristics. Czechs are often tolerant to other cultures, moreover Ukrainian culture is not much different and does not create difficulties in the working relationship. Based on the fact that the chosen company has no conflicts associated with work behavior and differences in mentality, it's hard to define my contribution to this organization work.
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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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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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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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