Number of results to display per page
Search Results
4602. Evaluation of granite weathering in the Jeroným Mine using non-destructive methods
- Creator:
- Ledniká, Markéta and Zdeněk Kaláb
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, zvětrávání, žuly, doly, weathering, granites, mines, ultrasonic pulse velocity, Schmidt hammer, 7, and 551
- Language:
- English
- Description:
- The paper presents the results of experimental examination of the weathering grade of granite rock mass in the medieval Jeroným Mine (Czech Republic). This mine is declared as a cultural heritage site of the Czech Republic therefore, non-destructive methods for determination of the Schmidt hammer rebound value and the ultrasonic pulse velocity were used to minimize negative impact on the historical workings during in situ exploration. Weathering grade of selected parts of the rockmass in underground spaces was classified visually according to the assumed classification (Hencher and Martin, 1982 in Vahed et al., 2009) and the above mentioned measurements were performed in these parts. Results show that the rebound value and the ultrasonic pulse velocity are decreasing with increasing weathering grade for all investigated parts. Therefore this result is possible to use as a supplementary method for evaluation of weathering grade of rock massif in this mine., Markéta Lednická and Zdeněk Kaláb., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4603. Evaluation of hepatic 11β-hydroxysteroid dehydrogenase activity by cortisone acetate test in young adults with diabetes mellitus type
- Creator:
- Kateřina Šimůnková, Richard Hampl, Hill, M., Lubomír Kříž, Jana Vrbíková, Hana Kvasničková, and Karel Vondra
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kortizol, diabetes mellitus, cortisol, cortisone, cortisone acetate test, peripheral metabolism of glucocorticoids, 14, and 612
- Language:
- English
- Description:
- Cortisone acetate test was performed in twelve young adult patients with diabetes mellitus type 1, after dexamethasone administration to suppress endogenous cortisol production. Previous screening revealed that all of the subjects had peak cortisol responses in the range from subnormal to normal, as determined by a low-dose Synacthen test. The aim was to find out whether these patients would exhibit different conversion of cortisone to cortisol by 11β-hydroxysteroid dehydrogenase. Using multifactorial ANOVA the following significant relationships were obtained between cortisol or cortisol/cortisone ratio measured during the test and other para meters examined a) before dexamethasone suppression and b) du ring the test: a) Cortisol at 120 th minute negatively correlated with daily insulin dose and positively with basal aldosterone. Cortisol/cortisone ratio at 60th, 120th, 180th, and 240th minute negatively correlated with basal aldosterone/plasma reni n activity ratio, urinary free cortisol/24 hours and positively with basal dehydroepindrosterone sulphate. b) Cortisol at 120th minute negatively correlated with suppressed basal serum glycemia; cortisol/cortisone ratio during the whole test negatively correlated with supressed basal ACTH. The examination of peripheral metabolism of cortisol using cortisone acetate test in patients with di abetes mellitus type 1 showed adaptive changes of 11β-hydroxysteroid dehydrogenace activity associated with altered cortisol tissue supply., K. Šimůnková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4604. Evaluation of levelling data for use in vertical crustal movements model in Poland
- Creator:
- Kowalczyk, Kamil and Rapinski, Jacek
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodezie, geodesy, vertical crustal movements, kinematic height frame, 7, and 551
- Language:
- English
- Description:
- The development of an elevation frame requires a movement model of the Earth's crust. Currently, regardless of the existence of ASG-EUPOS, it seems that the most reasonable approach is to use the model developed from the levelling data. In Poland three maps of vertical crustal movements were developed on the basis of levelling data. The most recent version was published in 2006. In the above mentioned elaborations, the vertical crustal movements were calculated from two subsequent first order levelling campaigns. The results of all four levelling campaigns in Poland were accumulated and digitalized to include more data. The colocation method was used to develop the model. The graphical representation was made with triangulation and linear interpolation. One unified database was developed on the basis of collected and unified data set of unadjusted observations. The first trials of common use of the three first order levelling campaigns were performed in 2008. However the available levelling data was not complete. The goal of this paper is to evaluate the usefulness of the data from the last three campaigns of precise levelling for the development of vertical movement model in Poland., Kamil Kowalczyk and Jacek Rapinski., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4605. Evaluation of long-term BeiDou/GPS observation quality based on G-Nut/Anubis and initial results
- Creator:
- Zhao, Lewen, Jan Douša, Václavovič, Pavel, Ye, Shirong, and Xia, Fengyu
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geodynamika, geomechanika, geofyzika, geologie, otevřený software, jakost, geodynamics, geomechanics, geophysics, geology, open source software, pozorování, G-Nut/Anubis, pre-processing, BeiDou, observation quality, open source, 7, and 551
- Language:
- English
- Description:
- Reliable observations are the prerequisite for high-precision GNSS data processing. Data quality evaluation at the pre-processing procedure can help the user to identify the weakness of the observations. The open source software package G-Nut/Anubis developed at Geodetic Observatory Pecny (GOP) is introduced and used for the evaluation of long-term BeiDou/GPS signal. Several key indicators are selected to evaluate the BeiDou/GPS observations. Quantitative analysis shows that more than 100 stations can achieve 6-hour standalone BeiDou positioning at least. The completeness of the BeiDou phase and code observations at three frequencies is higher than that of the GPS observations in the selected station which is mainly attributed to the high elevation observations from GEO and IGSO satellites. Qualitative analysis shows that the multipath effects for pseudorange observations are correlated with signal, receiver types and firmware versions besides the station environment. Users attempting to improve the pseudorange observations by multipath filter should pay attention also to the receiver-specific settings. Cycle slip counts are used to indicate the quality of carrier-phase observations. Results show that BeiDou C05 satellite is more affected by the cycle slips, in particular the third frequency observables. For GPS, the third frequency is more robust compared to the legacy frequencies. Comprehensive single point positioning results show that positioning accuracy for BeiDou is worse than that of GPS, which is mainly caused by less active satellites, worse geometry and the larger errors in the broadcast ephemeris. The BeiDou positioning accuracy was further degraded by the C13/C15 satellite and dominated by large clock errors. Broadcast evaluation shows that the BeiDou orbit errors are related to the constellations. Overall, the orbit precision for both GPS and BeiDou has been gradually improved. Outliers were observed for navigation records assigned with the healthy status, especially for BeiDou broadcast orbits. and Zhao Lewen, Dousa Jan, Vaclavovic Pavel, Ye Shirong, Xia Fengyu.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4606. Evaluation of mining subsidence using GPS data
- Creator:
- Doležalová, Hana, Vlastimil Kajzar, Kamil Souček, and Staš, Lubomír
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, poddolování, tektonika, undermining, geotectonics, subsidence depression, tectonic faults, 7, and 551
- Language:
- English
- Description:
- The observation network was built for the repeated determination of spatial position of points by means of the GPS method. It was built on the surface above extracted mining panels near Karviná, to monitor the development of subsidence depression in non-trivial geo-mechanical conditions. Two years of repeated surveying gave us the information about the process of creating of the subsidence depression in such area. The results gained so far show the important influence of the complicated tectonic situation on the behaviour of surface subsidence. A smooth development of subsidence depression without important irregularities was found out on sites without tectonic faults, while on sites where rock mass is disturbed with tectonic faults, the shape of subsidence depression is very irregular., Hana Doležalová, Vlastimil Kajzar, Kamil Souček and Lubomír Staš., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4607. Evaluation of molecular changes of distal organs after small bowel transplantation
- Creator:
- Pavel Urban, Rabajdová, M., Feterik, Š., Bódy, G., Granda, T., Mária Mareková, and Veselá, J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- apoptóza, cytokiny, genová exprese, apoptosis, cytokines, gene expression, inflammation mediators, molecular chaperones, 14, and 612
- Language:
- English
- Description:
- The ischemia and reperfusion of a jejunal graft during transplantation triggers the stress of endoplasmic reticulum thus inducing the synthesis of pro-inflammatory cytokines. Spreading of these signals stimulate immunological reactions in distal tissues, i.e. lung, liver and spleen. The aim of this study was to detect the molecular changes in liver and spleen induced by transplanted jejunal graft with one or six hours of reperfusion (group Tx1 and Tx6). Analysis of gene expression changes of inflammatory mediators (TNF-α, IL-10) and specific chaperones (Gadd153, Grp78) derived from endoplasmic reticulum (ER) was done and compared to control group. The qRT-PCR method was used for amplification of the specific genes. The levels of corresponding proteins were detected by Western blot with immunodetection. Protein TNF-α was in liver tissue significantly overexpressed in the experimental group Tx1 by 48 % (p<0.001). In the group Tx6 we found decreased levels of the same protein to the level of controls. However, the protein concentrations of TNF-α in spleen showed increased levels in group Tx1 by 31 % (p<0.001) but even higher levels in the group Tx6 by 115 % (p<0.001) in comparing to controls. Our data demonstrated that the spleen is more sensitive to posttransplantation inflammation than liver, with consequent stress of ER potentially inducing apoptosis and failure of basic functions of lymphoid tissue., P. Urban, M. Rabajdová, Š. Feterik, G. Bódy, T. Granda, M. Mareková, J. Veselá., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4608. Evaluation of numidian quartz sandstones from Southern Italy for industrial applications
- Creator:
- Fornelli, Annamaria and Micheletti, Francesca
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geologie, geology, Numidian quartzarenites, raw material for industry, stone resources in Campania and Lucania regions, Southern Italy, 7, and 551
- Language:
- English
- Description:
- a1_Numidian quartz-rich sandstones collected from four different reconstructed sections along the Apennine chain of Southern Italy, have been studied for their textural, petrographic and geochemical characteristics to verify their potential industrial use. Sampling was carried out along a NW-SE transect: Monteverde and Aquilonia sections at NW (Campania Region) and Valsinni and Rotondella ones at SE (Lucania Region). The sandstones from NW successions are subarkoses with subordinate sublitharenites. High compositional maturity is shown by these sandstones containing high SiO2 values (93wt% in average) and lowest amounts of CaO (0.08 wt%), MgO (0.1wt%), Fe2O3 (0.9 wt%) due to the absence of carbonate components (cement and lithics) and scarce presence of clay-ferruginous cement. The sandstones from SE successions show lower contents of SiO2 (87 wt% in average) and relatively higher contents of CaO (up to 7.4 wt%), MgO (up to 1.9 wt%) and Fe2O3 (up to 4.6 wt%) as compared to the previous ones, connected to the presence of calcite and clay-ferruginous cements; these can be classified as Fe-sands with subordinate sublitharenites. The sandstones from NW area show a better potential vocation to be used in the glass industry. However, the coloring elements contents are too high for clear or optical glass production. They are it is suitable as raw material for colored glass, insulating fibres, foundry molds or air Crete. With the aim of assessing the possible improvement of chemical characters, four granulometric fractions (A< 63 μm, B 63-125 μm, C 125-250 μm and D >250μm) were analyzed considering four samples from NW successions., a2_Based on chemical composition, C and D fractions from Aquilonia area, are the most suitable for a coloured glass, while fractions A (<63 μm) and B (63-125 μm) mixed in proportions of 40 % (A) and 60 % (B), appropriately cleaned of clays, heavy minerals and iron hydroxides, could be used as raw material for the paint industry. The obtained results suggest a complete exploitation of this type of sandstones in the manufacturing industry, reducing waste materials and enhancing the economic value of these resources from southern regions of Italy., Annamaria Fornelli and Francesca Micheletti., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4609. Evaluation of oxidative status in acetaminophen-treated rat hepatocytes in culture
- Creator:
- Tomáš Roušar, Otto Kučera, Pavla Křiváková, Halka Lotková, Roman Kanďár, Mužáková, V., and Zuzana Červinková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, biochemie, jaterní buňky, biochemistry, liver cells, acetaminophen, hepatotoxicity, gluthatione, ROS, 14, and 612
- Language:
- English
- Description:
- The present study describes the estimation of acetaminophen (AAP) toxicity in cultured rat hepatocytes. We used different concentrations of AAP - 1, 2. 5, 5, 10 and 20 mM, to test influence of AAP on cellular viability, functional capacity and oxidative status at given time intervals. WST-1 test showed decrease of dehydrogenase activity in 5, 10 and 20 mM AAP to 75 % of control values after 1 hour of incubation. At 12 h of treatment, all AAP concentrations decreased WST-1 signal; no enzyme activity was found since 18 h in cells treated with 20 mM AAP according to LDH leakage test performed at 24 h of incubation. Functional capacity was tested by albumin assay where the decrease was strictly related to AAP dose. Intracellular oxidative status was assessed by analysis of GSH/GSSG levels and time course of ROS production and glutathione reductase (GR) activity. Increased ROS prod uction was found already after 3 h of incubation in 2.5, 5, 10 and 20 mM AAP, respectively. The highest ROS production was measured after 12 h treatment. GR activity was decreased already after 3 h of incubation and remained also decreased in cells treated with 2.5, 5, 10 and 20 mM AAP during further incubation., Tomáš Roušar ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4610. Evaluation of photosynthetic performance of wheat cultivars exposed to boron toxicity by the JIP fluorescence test
- Creator:
- Öz, M. T., Turan, Ö., Kayihan, C., Eyidoğan, F., Ekmekçi, Y., Yücel, M., and Öktem, H. A.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, pšenice, bor, photosynthesis, wheat, boron, chlorophyll fluorescence, fluorescence transient, performance index, Triticum aestivum L, 2, and 581
- Language:
- Multiple languages
- Description:
- The changes in growth and photosynthetic performance of two wheat (Triticum aestivum L.) cultivars (Bolal-2973 and Atay-85) differing in their sensitivity to boron (B) toxicity were investigated under toxic B conditions. Eight-day old seedlings were exposed to highly toxic B concentrations (5, 7.5, and 10 mM H3BO3) for 5 and 9 days. Fast chlorophyll a fluorescence kinetics was determined and analysed using JIP test. Growth parameters, tissue B contents, and membrane damage were measured at two stress durations. The photochemical performance of PSII was hindered more in the sensitive cultivar (Atay-85) than that of the tolerant one (Bolal-2973) under B toxicity. The increase in the B concentration and stress duration caused membrane leakage in both cultivars. However, higher membrane damage was observed in Atay-85 compared to Bolal-2973. Additionally, significant reduction of growth parameters was observed in both cultivars at toxic B concentrations. The accumulation of B was higher in shoots than in roots of both cultivars. Nevertheless, Atay-85 translocated more B from roots to leaves compared to Bolal-2973. The advantages of certain JIP test parameters were demonstrated for evaluation of PSII activity in plants exposed to B stress. Evaluation of photosynthetic performance by JIP test as well as assessment of growth and tissue B content might be used to determine the effects of B toxicity in wheat. The results indicated lesser sensitivity to B toxicity in Bolal-2973 compared to Atay-85., M. T. Öz, Ö. Turan, C. Kayihan, F. Eyidoğan, Y. Ekmekçi, M. Yücel, H. A. Öktem., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public