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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Vliv tasemnice (Hymenolepis diminuta) na bioakumulaci zinku v těle hostitele (Rattus norvegicus) / Effect of tapeworm (Hymenolepis diminuta) on bioaccumulation of zinc in the host (Rattus norvegicus)

Sloup, Vladislav January 2016 (has links)
This research investigates the ability of rat tapeworm (Hymenolepis diminuta) to accumulate zinc in tissue and the influence of its intake and excretion by its host (laboratory rat). The host was fed by food with zinc in two forms: 1) a mixture of standard food ST1 with hyperaccumulator plant Arabidopsis halleri, 2) ST1 mixture with zinc lactate, which is ordinarily used as a feed supplement for increasing zinc content and it is often included in human diet supplements. Rat control group fed by ST1 only was included in the experiment for verification of the difference. Rats were divided to six groups (OO, OT, RT, RO, MO a MT). Three rat groups were infected by rat tapeworm (OT, RT, MT) and three rat groups were not infected (OO, RO, MO). The control groups OO and OT were fed by ST1 only. RO and RT groups were fed by ST1 with admixture of Arabidopsis halleri and groups MO and MT were fed by ST1 with zinc lactate. Urine and excrements of the rats were collected twice a week during the experiment and their amounts were measured every day. The rats were weighted every week. At the end of the balance phase of the experiment rats were euthanized and seven selected tissues were removed (liver, kidney, spleen, small intestine, testis, muscle and bone). Rat tapeworm was removed from the infected rats. Blood was drawn from the rats. The results show that rat groups infected by the rat tapeworm had lower concentration of zinc in almost all analyzed tissues except for spleen, where the concentration of zinc was the same as in groups without the rat tapeworm. Based on the results the rat tapeworm also has an influence on the excretion of feces and urine.
2

Interakce mezi infekcí tasemnicí a zatížením hostitele těžkými kovy / Interaction between tapeworm infection and heavy metals accumulation in the host

Magdálek, Jan January 2016 (has links)
Heavy metals in living organisms occur in trace amounts. While zinc is an essential element wich is indispensable for many physiological processes, cadmium in body acts as atissue toxin, that can cause oxidative stress and contribute to cancer development. Recent studies suggest that some species of tapeworms (Cestoda) and Acantocephala are able to absorb in their tissue higher quantity of heavy metals in comparsion with their hosts. Moreover it was observed that In connection with the increased accumulation of heavy metals in the tissue of tapeworm was decreased amounts of these metals in the organs of the host. The aim of this thesis was to investigate whether the rat tapevorm (Hymenolepis diminuta) causes a decrease in the concentration of Cd and Zn in the organs of rats. A total of 24 Wistar rats (Rattus norvegicus) were divided into 4 groups (n=6). Groups PT and 0P take increased doses of kadmium (3,0 mg/week) and zinc (235,7 mg/week) for six weeks. This increased intake was achieved by adding Arabidopis halleri to feed. After six weeks rats were killed and concentrations in their tissues (bone, muscle, testes, spleen, intestine, liver kidney) were analyzed. Subsequent statistical tests confirmed lower levels of Cd and Zn in some organs of rats infected with tapeworm compared to rats without infection. For example in kidney, liver ant intestine of infected rats was detected 2,9; 2,5 and 1,8 times lower concentrations of cadmium and zinc in comparsion with uninfected rats. Tapeworm absorbed 1695 time higher amount of kadmium compared to the host muscle. The zinc content was lower in all organs (except spleen and testes) of infected rats in comparsion to uninfected. In kidney, liver and intestine of infected rats was 1,2; 1,25 and 1,4 times lower average concentration of zinc in comparsion with uninfected rats. The tape worm absorb higher concentration of zinc compared to all organs of the host.
3

Vyhodnocení využití území pro akumulaci povrchových vod výhledové lokality Hukvaldy

Štefek, Petr January 2008 (has links)
No description available.
4

Srovnání transportu a distribuce organického polutantu a trofických látek v rostlinách hrachu (Pisum sativum L.)

Francová, Jana January 2018 (has links)
In this work, the transport and accumulation of 14C-fluoranthene (14C-FLT) and 14C-glycine (14C-gly) in pea seedlings (Pisum sativum L.) were observed after treatment of the substances to the nutrient solution and point-to-leaf. The aim of the work was to compare the transport and distribution of the above substances in pea plants. For this reason, the pea plants were attacked by aphids that penetrated the phloem by stylet. Samples were collected after 2, 24, 48 and 72 hours after the addition of 14C-FLT or 14C glycine to the nutrient solution or to the leaf. Transport and distribution the 14C-activities originatted from 14C-FLT or 14C glycine uptake were monitored by the liquid scintillation technique after combustion in oxygen flow. The results proved that 14C-FLT and 14C-gly translocates both from the nutrient solution and from the point of ap-plication on the leaf to the youngest part of the plant, to apices as significante sinks. Even 14C-activity was detected in aphids, which demonstrated FLT and glycine trans-port via phloem.
5

Proměnlivost rozmístění akumulačních a erozních tvarů uvnitř koryta v závislosti na výskytu překážek a jeho průběhu na různě velkých tocích / Spatial distribution of erosion and accumulation landforms within the river channel depending on the channel course and barriers for various large river

Marková, Jana January 2016 (has links)
The subject of the diploma thesis is the change in the spatial distribution of erosion and sediment deposition landforms within the channel of four different-size rivers, and is based on the morphology of the river channel and presence of barriers. The objective of this thesis was to 1) map the spatial distribution of channel bars and locations of bank scour, 2) define the morphologic characteristics including the position with respect to the location of bends and obstructions in the channel of the individual river reaches, and 3) define common patterns, and explain potential differences between the patterns in the rivers of different size. For the purpose of this study a field reconnaissance was carried out on selected reaches of Sazava River, Litavka River, Kocaba River and Lodenice River. The selected sections represent relatively natural parts of river channels with similar geomorphic conditions. The field survey was carried out in two campaigns - in spring and in summer 2015. The results of the survey indicate that channel bends do not play a primary role in the position and morphology of channel bars and locations of bank scour. However, significant sediment deposition or erosion activity was identified near run-of-river dams. In the surveyed reaches of the Sazava and Litavka rivers, channel...
6

Vliv draslíku na akumulaci Cs ďáblíkem bahenním / Impact of potassium on accumulation of Cs by Calla palustris

Poláková, Monika January 2016 (has links)
Environmental contamination with radionuclides is a growing problem in the world. Phytoremediation seems to be a suitable method for the removal of radionuclides from the environment. The aim of this study was to determine the impact of potassium on accumulation of stable isotope 133Cs and evaluate the suitability of plant species Calla palustris for phytoremediation. Plants were grown in a water solution in a greenhouse and after one week of pre-cultivation were exposed to stable isotope 133Cs (0,5 mM CsCl). Potassium was added in five various concentrations in the form of K2SO4. The level of cesium in plants was measured after 8 days of exposition. Plants without added potassium absorbed the most cesium (11,52 %). Plants with the highest concentration of added K2SO4 10 mM (3,45 %), 5 mM (3,62 %), 2 mM (5,57 %) absorbed the least. Higher 133Cs accumulation was measured in the plant roots than in the above- ground plant parts. Total uptake of cesium by Calla palustris suggests the possibility to use Calla palustris for phytoremediation.
7

Vliv dusíku na akumulaci Cs ďáblíkem bahenním / Impact of nitrogen on accumulation of Cs by Calla palustris

Benediktová, Eva January 2016 (has links)
This work deals with the evaluation of Calla palustris utilization for phytoremediation and clarifying how nitrogen influences the uptake of cesium from aqueous solution. The plants were subjected to nitrogen exposure, which consisted of five different concentrations of NH4+ and NO3- and 0.5 mM CsCl, for eight days. The greatest amount of cesium (13.5%) accumulated the plants without the addition of nitrogen, the smallest amount accumulated plants with concentrations of 6: 3 (3.9%), 8: 4 (3.6%) and 10: 5 NH4NO3: NH4Cl (3.5%). Calla has proved to be suitable for phytoremediation, however with the need for longer exposure. Besides these main hypotheses it has been moreover shown that the state of plants affected the uptake of cesium and that nitrogen influenced the condition of the plant. Further it has not been observed noticeable difference in uptake of cesium in roots and stems with leaves.
8

Vliv draslíku na příjem stabilního cesia ďáblíkem bahenním z vodného roztoku / Effect of potassium on stable cesium uptake by Calla palustris from aqueous solution

Petrůvová, Nicola January 2017 (has links)
The aim of the thesis was to evaluate the effect of potassium on receiving of stable cesium and evaluate the appropriateness of Marsh Calla (Calla palustris) for phytoremediation. The experiment was conducted in a green-house environment where the plants were grown in an aqueous solution. The plants were exposed then to a stable isotope of cesium (133Cs) at a concentration of 1 mM CsCl. Potassium was added to the plants in the form of potassium sulphate (K2SO4), in five different concentrations (0.5 mM, 1 mM, 2 mM, 5 mM and 10 mM). Plants were exposed for 8 days. The largest average income of cesium (9,37 %) had a plant without added potassium. The root part of the plants showed a greater cesium content than the ground part. Based on the total intake of cesium from an aqueous solution, calla marsh can be estimated as a plant usable for phytoremediation.
9

Aplikace modelu SRM pro modelování akumulace a tání sněhu v experimentálních povodích Bystřice a Zlatého potoka v Krušných horách / Application of the Snowmelt Runoff Model for snow accumulation and snowmelt modelling in experimental catchments Bystřice and Zlatý Brook in the Krušné Mountains

Šedivá, Kateřina January 2013 (has links)
Title: Application of the Snowmelt Runoff Model for snow accumulation and snowmelt modelling in experimental catchments Bystřice and Zlatý Brook in the Krušné Mountains Modelling of hydrological processes is a dynamically developing part of hydrology. The Snowmelt Runoff Model (SRM) was applied for modelling the runoff in two experimental catchments Bystřice and Zlatý Brook. The aim of this thesis is to set up and calibrate SRM model and to evaluate methods and procedures used for runoff simulations. The SRM model was used for modelling snow accumulation and snowmelt in two selected catchments in the Krušné Mountains. The snow depths and snow water equivalents are measured since 2009 at selected locations situated in catchments. Calibration and validation of the model was based on continual time series of precipitation, air temperature and discharge measured 2009. Hydrological years 2009 and 2010 were used for model calibration and hydrological years 2011 and 2012 were used for model validation. Sensitivity analysis, which quantifies the effect of individual model parameters on the simulating proces, was carried out based on results. Recession coefficient and runoff coefficient belong to the most sensitive parameters with highest impact on runoff simulations. Model calibration was successful, which...
10

Vliv dlouhodobého hnojení travního porostu na obsah rizikových prvků v půdě / Effect of long-term fertilizer application on content of risk elements in grassland soil

Jungová, Michaela January 2017 (has links)
The long-term Steinach Grassland Experiment is probably one of the oldest still-running fertilised grass experiments in continental Europe. The experiment was established on an alluvial meadow Alopecurus pratensis in southeastern Germany in 1933. The meadow was divided into 75 plots and fertilised with both mineral and organic fertilisers of differing compositions and amounts. The aim of this study was to provide more detailed information about the effects of long-term fertilisation by natrium (N), phosphorus (P) and potassium (K) on the contents of risk elements in soil. The effects of long-term fertilisation were investigated in the extracts of a) plant-available elements (extraction of CaCl2), b) easily mobilised elements (extraction of EDTA), c) potentially mobilisable elements (extraction of HNO3), the total concentration of elements (extraction of Aqua regia). Concentrations of risk elements As, Cr, Cu, Fe, Mn, Ni and Zn in the soil profile has increased substantially due to the phosphorus fertilisation; however, the limits for total trace elements concentration as set by the Czech legislation have been exceeded only twice, namely in the case of As and Cd. The total concentration of As (AsT) has been exceeded only once, on the plot fertilised only by nitrogen. The assumption is that that the increased level of AsT fraction in soil was probably caused in the past by fertilising with Thomas slag which is known to contain elevated concentrations of As. However, fertilising with the phosphorus-containing fertilisers has had the opposite effect on concentrations of Mn, Ni and Zn that are easily available to plants; concentrations of these elements in the soil extraction were substantially higher. In spite of the overall concentrations of Cd being lower than the Czech legislative standards, the results on several plots fertilised by mineral and organic fertilisers containing N, P and K showed higher concentrations of Cd and in one case reached the limit value. Plots fertilised by mineral fertilisers N160P44K174 (NH4)2SO4 recorded higher Cr concentrations. In overview, it could be stated that under various types of fertilising no substantial effects of long-term fertiliser applications on a higher content of risk elements in soil has been detected. Only two plots have exceeded the limits set by Notice 13/1994 Sb., in one case it was a total concentration of As and in another one that of Cd.

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