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6162. Influence of chemical and mineralogical composition of metakaolin on mortar characteristics
- Creator:
- Velosa, Ana Luisa, Rocha, Fernando, and Veiga, Rosário
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, metakaolin, mineralogie, malty, mineralogy, mortar, chemical composition, 7, and 551
- Language:
- English
- Description:
- Three different metakaolins processed by a Portuguese factory were studied aiming to assess the influence of chemical and mineralogical composition of metakaolin on mortar characteristics. Mineralogical analysis of both the fine and clay fractions was carried out by X-ray diffraction. Chemical composition (major elements) was analyzed by X-ray fluorescence. Mineralogical composition reveals some significant differences between the studied samples, in both analyzed fractions, metakaolin 2 being richer in kaolinitic minerals. From a chemical point of view, siliceous content is always high (aroun d 60 %) as well as Al2O3 content (around 30 %); once again metakaolin 2 is the one richer in Al2O3 and poorer in sodium and potassium. Metakaolin from the three different batches was incorporated in lime mortars in order to produce a pozzolanic reaction and hence enable them to harden in high relative humidity conditions or, when access to CO2 is limited, as in the case of mortars supporting glazed tiles. Mortars with the same volum etric ratio were tested for flexural and compressive strength at ages of 28 and 90 days, and the module of elasticity was dete rmined. A relation between the mechanical strength achieved by lime mortars with the addition of metakaolin from different batches and metakaolin mineral and chemical composition was assessed. The knowledge of the influence of the metakaolin com position on the strength of the mortars is an important step in improving their performance and extending their application., Ana Luisa Velosa, Fernando Rocha and Rosário Veiga., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6163. Influence of chronic toxoplasmosis on some human personality factors
- Creator:
- Flegr, J. and Hrdý, I.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Toxoplasma, toxoplasmosis, behaviour, personality factors, Cattell’s questionnaire, and manipulation hypothesis
- Language:
- English
- Description:
- An effect of parasites on host behaviour was tested on the toxoplasma-human model. Three hundred and thirty-eight (338) people were assessed with Cattell’s personality questionnaire and then tested for Toxoplasma gondii infection with a delayed type hypersensitivity test for Toxoplasma. A highly significant correlation between chronic toxoplasmosis and two personality factors (G- Low Superego Strength and L- Protension) was found (p = 0.0032 and 0.0020, respectively). A correlation of the intensity of the personality factor-shifts with the duration of the infection (estimated from antibody titer) suggests that toxoplasmosis induces the shift in human personality, rather than the personality factors G and I. influence an acquisition rate of Toxoplasma gondii infection.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6164. Influence of collagen and chondroitin sulfate (CS) coatings on poly-(lactide-coglycolide) (PLGA) on MG 63 osteoblast-like cells
- Creator:
- Vandrovcová, M., Douglas, T., Hauk, D., Grössner-Schreiber, B., Wiltfang, J., Lucie Bačáková, and Warnke, P. H.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kolagen, biodegradovatelné polymery, osteoklasty, popraviště, collagen, biodegradable polymers, osteoclasts, scaffolds, glycosaminoglycan, 14, and 612
- Language:
- English
- Description:
- Poly-(lactide-co-glycolide) (PLGA) is an FDA-approved biodegradable polymer which has been widely used as a scaffold for tissue engineering applications. Collagen has been used as a coating material for bone contact materials, but relatively little interest has focused on biomimetic coating of PLGA with extracellular matrix components such as collagen and the glycosaminoglycan chondroitin sulfate (CS). In this study, PLGA films were coated with collagen type I or collagen I with CS (collagen I/CS) to investigate the effect of CS on the behaviour of the osteoblastic cell line MG 63. Collagen I/CS coatings promoted a significant increase in cell number after 3 days (in comparison to PLGA) and after 7 days (in co mparison to PLGA and collagen-coated PLGA). No influence of collagen I or collagen I/CS coatings on the spreading area after 1 day of culture was observed. However, the cells on collagen I/CS formed numerous filopodia and displayed well developed vinculin-containing focal adhesion plaques. Moreover, thes e cells contained a significantly higher concentration of osteocalcin, measured per mg of protein, than the cells on the pure collagen coating. Thus, it can be concluded that collagen I/CS coatings promote MG 63 cell proliferation, improve cell adhesion and enhance osteogenic cell differentiation., M. Vandrovcová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6165. Influence of dietary sesamin, a bioactive compound on fatty acids and expression of some lipid regulating genes in Baltic Atlantic salmon (Salmo salar L.) juveniles
- Creator:
- Trattner, S., Ruyter, B., Østbye, T. K., Kamal-Eldin, A., Moazzami, A., Pan, J., Gjøen, T., Brännäs, E., Zlabek, V., and Jana Picková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, cytochromy, cytochromes, sesamin, episesamin, topopherols, cytochrome P450, peroxisome proliferator-activated receptor, hormone sensitive, scavenger receptor type B, 14, and 612
- Language:
- English
- Description:
- The effects of inclusion of sesamin / episesamin in Baltic Atlantic salmon ( Salmo salar L.) diets based on vegetable oils were studied. The study was designed as a dose response study with two control diets, one diet based on fish oil (FO) and one diet based on a mixture of linseed and sunflower oil (6:4 by vol.) (MO). As experimental diets three different levels of inclusion of sesamin / episesamin (hereafter named sesamin) to the MO based diet and one diet based on sesame oil and linseed oil (SesO) (1:1 by vol.) were used. Th e dietary oils were mirrored in the fatty acid profile of the white muscle. Sesamin significantly decreased the levels of 18:3n-3 in the white muscle phospholipid (PL) fraction of all groups fed sesamin, no significant differences were found in the triacylglycerol fraction (TAG). Slightly increased levels of docosahexaenoic acid (22:6n-3, DHA) in PL and TAG were found in some of the sesamin fed groups. Sesamin significantly affected the expressi on of peroxisome proliferator- activated receptor α , scavenger receptor type B and hormone sensitive lipase, in agreement wi th previous studies on rainbow trout ( Oncorhynchus mykiss ) and Atlantic salmon ( Salmo salar L.) hepatocytes published by our group. No significant effects on toxicological response measured as ethoxyresorufin O-deethylase activity was found. The total cytochrome P450 enzymes were significantly higher in MO 0.29 and SesO group. The amount of α - and γ -tocopherols in liver and the amount of γ -tocopherol in white muscle were significantly lower in fish fed the FO diet compared to the MO diet, but no difference after inclusion of sesamin was found in this study. Increased inclusion of sesamin increased the levels of sesamin and episesamin in the liver, but did not affect the amounts in white muscle., S. Trattner ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6166. Influence of different irradiance on growth and photosynthetic characteristics in seedlings of Rhizophora species
- Creator:
- Kathiresan, K. and Moorthy, P.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Seedlings of two species of Rhizophora {R. apiculaía and R. mucronala) were grown for 45 d under sun, shade, or dark in natural environment. The shade-grown plants showed optimum growth performance, efficient N03‘ utilization and photosynthetic characteristics (chlorophyli and carotenoid contents and their presence in pigment- protein complexes).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6167. Influence of different oxygen modes on the blood oxygen transport and prooxidant-antioxidant status during hepatic ischemia / reperfusion
- Creator:
- Zinchuk, V. V., Khodosovsky, M. N., and Maslakov, D. A.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hypoxie, hyperoxie, králíci, hypoxia, hyperoxia, rabbits, hemoglobin-oxygen affinity, hepatic ischemia, reperfusion, hypercapnia, 14, and 612
- Language:
- English
- Description:
- Oxygen supply was corrected in rabbits during the hepatic ischemia/reperfusion by means of different breathing mixtures: hypoxic (14.8 % O2+85.2 % N2), hyperoxic (78 % O2+20.2 % N2+ 1.8 % CO2), or hypercapnic (5 % CO2 in air). Hepatic ischemia was induced for 30 min by ligation of hepatic artery, reperfusion period lasted 120 min. Indices of blood oxygen transport (p50act, pCO2, pH, pO2, etc.) and prooxidant-antioxidant balance (Schiff bases, conjugated dienes, catalase, retinol, a-tocopherol) were measured in the blood and liver. The severity of reperfusion damage was evaluated by the activities of alanine and aspartate aminotransferases (ALT, AST) in the blood. Hepatic ischemia/reperfusion resulted in higher p50act in hepatic venous and mixed venous blood in all experimental groups. The changes of p50act were most marked in the hypercapnic group and were the weakest in the hypoxic group. The rise in p50act was accompanied by higher levels of lipid peroxidation products, ALT and AST in blood and liver homogenates, and by a simultaneous fall of α-tocopherol and retinol concentrations, except in the hypoxic group. Catalase activity at the end of reperfusion increased under normoxia, decreased under hyperoxia or hypercapnia and did not change under hypoxia. The moderate hypoxia during reperfusion was accompanied by a better balance between the mechanisms of reactive oxygen species production and inactivation that may be observed by optimal changes in p50act and reduced the hepatic damage in this pathological condition., V. V. Zinchuk, M. N. Khodosovsky, D. A. Maslakov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6168. Influence of dislocations on bumps occurrence in deep mines
- Creator:
- Petr Procházka, Jiřina Trčková, and Lok, Tat Seng
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, numerické modelování, doly, numerical modeling, mines, free hexagon method, deep mines, bumps occurrence, 7, and 551
- Language:
- English
- Description:
- The problem of bumps occurrence in deep mines during the long wall mining appears to be one of the most serious one in the design of engineering of mining. The bumps are caused for various reasons, but basically it is an aftermath of the accumulated energy, which is released under some unfavorable conditions. In this paper the influence of given dislocations and their slope in a coal seam are studied based. The numerical tool is the free hexagon method. This method belongs to a set of discrete element methods and enables us to define and calculate stresses in a natural way along the interfacial boundaries of adjacent particles (elements). Since the bumps are affected by a possible slip along the dislocations, dynamical response has to be taken into account. The velocity of excavation of the mine is considered by successive change of values of Eshelby’s forces on the face of the wall., Petr Pavel Procházka, Jiřina Trčková and Tat Seng Lok., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6169. Influence of diurnal and seasonal fluctuations in atmospheric CO2 concentration on the net CO2 exchange of poplar trees
- Creator:
- Veste, M. and W.B.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- diurnal course of gas exchange, stomatal conductance, Populus tremula, photosynthesis measurements, intemal CO2 concentration, and gas exchange techniques
- Language:
- Multiple languages
- Description:
- Diurnal and seasonal fluctuation in ambient CO2 concentration (C^) of more than 100 cm^ m‘3 in urban areas is an important abiotic factor influencing photosynthetic activity. This was shown in a young poplar tree under controlled environmental conditions. Here, the short-term rise in from 320 to 360 cm^ m‘3 during a day resulted in a 10 % higher CO2 gain. This variation in also influenced the interpretation of CO2 exchange data. Calculation of the intemal CO2 concentration in a leaf, Q, on the basis of an assumed mean value of atmospheric CO2 of 340 cm^ m'^ led to a possible 8 % divergence ffom the actual Cj in our experiments and thus also to a falše interpretation of the results, as it concealed the photosynthetic response to a rise or decline of Cg. Additionally, the changing CO2 concentration directly influenced the measurement by the infrared gas analyzer, because of its nonlinear response. Lack of compensation for this can lead to an additional inaccuracy of 3 to 8 % in the calculation of net photosynthetic rate and Q.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6170. Influence of drought stress on the photosynthetic characteristics and dry matter accumulation of hybrid millet
- Creator:
- Lu, H. B., Qiao, Y. M., Gong, X. C., Li, H. Q., Zhang, Q., Zhao, Z. H., and Meng, L. L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, chlorophyll fluorescence, gas exchange, Setaria italica (L.) Beauv., drought stress, 2, and 581
- Language:
- Multiple languages
- Description:
- In order to elucidate the drought resistance and high-yield mechanism of hybrid millet, we studied the influence of drought stress on the photosynthetic characteristics and dry matter accumulation. Our results revealed that drought stress caused lesser reduction in the net photosynthetic rate, maximal quantum yield of PSII photochemistry, excitation energy capture efficiency of PSII reaction centers and in the yield of hybrid millet compared to normal millet. When drought stress occurred in the jointing stage, the percentage decrease of PN, Fv/Fm, Fv′/Fm′, and the yield of Zhangzagu3 cultivar compared to control were 27.9%, 2.6%, 25. 5%, and 1.9%, respectively, the percentage decrease of Zhangzagu5 were 37.6%, 3.9%, 28.3%, and 16.7%, respectively, the decrease percentage of Datong29 were 60.1%, 6.4%, 4%, and 23.4%, respectively. Hybrid millet showed the similar reduction in the parameters referred above, when drought stress occurred at the heading stage, but the percentage decrease was much higher than that at the jointing stage. We concluded that hybrid millet showed higher drought resistance than normal millet., H. B. Lu, Y. M. Qiao, X. C. Gong, H. Q. Li, Q. Zhang, Z. H. Zhao, L. L. Meng., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public