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Sorption and Stabilization of Metals/Mettalloids by Innovative Synthesized Sorbent Amochar.
Ouředníček, P. ; Trakal, L. ; Komárek, M. ; Pohořelý, Michael
Remediation of contaminated soil which is based on stabilization and immobilization of potential\nhazardous substance by sorption materials has been studied intensively nowadays. Biochar – activated organic carbon belongs to this group of stabilizing agents which can adsorb wide range of contaminants, including metals/metalloids. Surface area of the biochars is quite large in general and functional groups (e.g. COO–) can form chelates or alkaline elements on the surface, which is represented by cation exchange capacity. Altogether with the high pH values (7.00 – 10.00), biochars are quite effective sorbents and can adsorb metals/metalloids from the solution (ground water), especially in acidic soils (in the environments affected by intensive mining activities). Sorption\neffectiveness can be increased (especially for As (V) or Cr (VI) sorption) by modification of biochar by various types of secondary oxides. Innovative sorbent AMOchar (AMO + biochar) has been synthesized currently. The product was prepared by adding of biochar to the reaction solution during amorphous manganese oxide (AMO) synthesis. The AMOchar was formed mainly by Mn-oxalates which had coated surface of the pristine biochar. AMOchar composite was able to remove significantly higher amounts of various metal(loid)s from the solution despite the rather high pH of the material. Sorption effectiveness was high not only in case of Pb (II) sorption (almost 99%), and Cd(II) (51.2%), but also a very high amount of As(V), 91.4%. Additionally, both AMOchar composite was able to reduce Mn leaching. This can avoid potential post-contamination caused by the dissolution of less stable Mn-oxalates as observed in the pure AMO.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_22316111113040 - PDF
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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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Information content in vocalization of guinea pigs (Cavia porcellus): individual distinction and recognition of predators
Baklová, Aneta ; Baranyiová, Eva (advisor) ; František, František (referee)
Guinea pigs represent domesticated precocious rodents which became common pets. From the first day after birth they are fully vocal. This thesis was devoted
to the vocalization of pups. The aim of the thesis was to 1) determine the age when the vocal individuality in whistle sound is demonstrable; 2) test possible ultrasonic signals emitted by young guinea pigs; 3) study the antipredator reactions and alarm calls to aerial (bird of prey) and terrestrial (dog) predators and human (control test).
A total of 16 guinea pig pups were tested for vocal individuality, 28 pups
for ultrasonic vocalization and 27 adolescents for predator recognition. When testing vocal ontogeny during the first 9 days after birth, I observed changes in temporal, frequency and parameter of intensity . When I test vocal individuality by cross-validated discriminant function analysis (DFA) based on ten acoustic parameters, calls were classified to correct animals with following success: day 1 = 71.9%, day 3 = 58.8%, day 5 = 53.10%, day 7 = 50.60% and day 9 = 63.10%. The highest frequency in whistle was 30.03 kHz. In predator discrimination reactions as freezing, fleeing and vigilance were observed. In the presence of dog, guinea pigs reacted for the longest time and most frequently by freezing. When confronted with a bird of prey, I observed for a longest time and most often fleeing and then freezing. When exposed to a human, guinea pigs showed mostly vigilance. Almost no vocalization was observed except for two events
of alarm calls - drrr as in the presence of dog and chirrup as reaction to bird of prey.
The following conclusions can be drawn from the presented results: 1) vocal individuality of guinea pigs is demonstrable immediately after birth and the rate
of individually different vocal parameters changes with age; 2) guinea pigs are able
to produce sound up to 30 kHz, i.e. within the ultrasound range, but signals of high frequencies are not crucial for their communication; 3) guinea pigs discriminate between terrestrial and aerial predators, but they emit alarm calls rather rarely.
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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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Predicting asp and pikeperch recruitment in a riverine redervoir.
BLABOLIL, Petr
Recruitment of two species, asp (Leuciscus aspius) and pikeperch (Sander lucioperca), in a riverine reservoir was studied using a novel statistical approach. Both species are piscivorous and are stocked into reservoirs for biomanipulative purposes to reduce planktivore species. Long-term data series were used, but the number of potential predictors was high. Therefore, a novel informative statistical approach based on dimension reduction methods was applied. Quality of outputs was driven by sampling methods. Main factors affecting asp recruitment were zooplankton abundance, predator density and temperature. In terms of pikeperch fry measured with seine and trawls, the number of predators was the only important factor. Gillnets underestimate small fish and the data were unsuitable for statistical modelling.
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Single particle analysis of size-segregated aerosol in Prague city center
Marvanová, S. ; Skoupý, Radim ; Kulich, P. ; Bendl, J. ; Hovorka, J. ; Machala, M.
Particulate matter (PM) is omnipresent pollutant in the ambient air known to cause cardiovascular and respiratory diseases (WHO 2004). Recently, outdoor air pollution and particulate matter in outdoor air pollution were classified as carcinogenic to humans, Group 1 (IARC 2015). Especially, ambient PM of aerodynamic diameter < 100 nm, ultrafine particles, appears to be of great importance due to its high specific surface area and high number concentration (Hughes et al. 1998). Ultrafine particles also easily enter and are being transferred in organisms, and interact with cells and subcellular components (Oberdorster et al. 2005). As the evidence of ultrafine PM significance increased, size-fractionated PMs sampled by various cascade impactors have been employed into the toxicological studies on cell cultures or isolated cells, using the organic extracts of size-fractionated PMs (Topinka et al. 2013, Topinka et al. 2015) or directly the size-fractionated particles (Becker et al. 2003, Ramgolam et al. 2009, Reibman et al. 2002, Loxham et al. 2013, Jalava et al. 2006, Thomson et al. 2015, Jalava et al. 2015). The aim of this study was to evaluate shape and composition of size-segregated aerosol particles, sampled by high volume cascade impactor, using electron microscopy and energy dispersive X-ray spectroscopy (EDX).
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Optical frequency references
Hrabina, Jan
Optical frequency references based on absorption cells represent a traditional and essential tool for frequency locking of precise laser standards. One of the most often used absorption media is a molecular iodine 127I2, which offers a rich atlas of strong and narrow absorption lines across mostly whole visible part of optical spectrum. The main disadvatage of this media can be seen in its high corrosivity and sensitivity to presence of foreign substances. This contribution is oriented to comparison of possible measurement methods for bulk- and also optical fiber- based iodine absorption cells quality and chemical purity testing.\n\n
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Oldtown's gradual (NK ČR, XVII.A.40), 1561-1567, from the manufactory of Jan Taborsky of Klokotska Hora
Součková, Ema ; Kubík, Viktor (advisor) ; Jarošová, Markéta (referee)
Oldtown's gradual The aim of this work is a monographic elaboration of the Oldtown's gradual (XVII.A.40), from 1561 to 1567, in the context of the work of Jan Taborsky of Klokotska Hora, with the emphasis on connotation of Žlutice gradual. The work elaborates and critically appraises the literature about the genesis and decor, deeply analyses its illuminations (through formal and iconographic analysis) and gives basic orientation in questions of analogies of its decor. Another goal of this work is a summarization of the decor of Oldtown's gradual and elaborated analysis of its illuminations. Oldtown's gradual is one of the best Renaissance manuscripts. The penman was Jan Taborsky of Klokotska Hora; chapter 2.1. deals with his life and production. Matous Ornys of Lindperk was the limner; chapter 2.2. deals with his work. Indisputably, he belongs to the best limners of the 16th century. The decor of the gradual is described in the chapter 4.2. Illuminations of gradual have conventional scheme of choral manuscripts. A lot of analogies are to be found in the medieval and also Renaissance manuscripts. There are elements of medieval literary paintwork, but also fully Renaissance elements: perfect linear perspective and high-quality scenery. Oldtown's gradual is one of the most beautiful and one of the...
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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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Exploitation of GPU in graphics and image processing algorithms
Jošth, Radovan ; Svoboda, David (referee) ; Trajtel,, Ľudovít (referee) ; Herout, Adam (advisor)
Táto práca popisuje niekoľko vybraných algoritmov, ktoré boli primárne vyvinuté pre CPU procesory, avšak vzhľadom k vysokému dopytu po ich vylepšeniach sme sa rozhodli ich využiť v prospech GPGPU (procesorov grafického adaptéra). Modifikácia týchto algoritmov bola zároveň cieľom nášho výskumu, ktorý bol prevedený pomocou CUDA rozhrania. Práca je členená podľa troch skupín algoritmov, ktorým sme sa venovali: detekcia objektov v reálnom čase, spektrálna analýza obrazu a detekcia čiar v reálnom čase. Pre výskum detekcie objektov v reálnom čase sme zvolili použitie LRD a LRP funkcií. Výskum spektrálnej analýzy obrazu bol prevedný pomocou PCA a NTF algoritmov. Pre potreby skúmania detekcie čiar v reálnom čase sme používali dva rôzne spôsoby modifikovanej akumulačnej schémy Houghovej transformácie. Pred samotnou časťou práce venujúcej sa konkrétnym algoritmom a predmetu skúmania, je v úvodných kapitolách, hneď po kapitole ozrejmujúcej dôvody skúmania vybranej problematiky, stručný prehľad architektúry GPU a GPGPU. Záverečné kapitoly sú zamerané na konkretizovanie vlastného prínosu autora, jeho zameranie, dosiahnuté výsledky a zvolený prístup k ich dosiahnutiu. Súčasťou výsledkov je niekoľko vyvinutých produktov.
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