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561. George C. Papageorgiou and the protective role of glycine betaine in activation and stabilization of the oxygen-evolving photosystem II complex

Creator:
Murata, N. and Stamatakis, K.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
glycine betaine, glycine betaine-synthesizing cyanobacteria, and oxygen-evolving photosystem II complex
Language:
Multiple languages
Description:
We present here our adventures in research in photosynthesis with George C. Papageorgiou (1933-2020) focusing on George's initiative in the discovery of the protective effects of glycine betaine on the oxygen-evolving photosystem II complex. We end with a brief description of research on glycine betaine-synthesizing transgenic cyanobacteria. Two of us, Norio Murata (in Japan) and Kostas Stamatakis (in Greece), and all our collaborators, have the highest respect for George, and we miss him and our intense discussions with him on various topics of photosynthesis research.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

563. Geotechnical performance of combined stone columns and piles capped with reinforced concrete raft foundation in soft clay soil

Creator:
Ahmed, Danish, Taib, Siti Noor Linda bt, Ayadat, Tahar, and Hasan, Alsidqi
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
stone columns, piles, raft foundation, combined, and soft soils
Language:
English
Description:
Stone columns consist of granular material compacted in long cylindrical holes. They are used for improving the strength and consolidation characteristics of compressible soils. However, they are still less effective at supporting heavy loads, since they still cannot transfer applied stresses to deeper layers of soil. The main objective of this numerical study was to investigate the geotechnical performance of a combined foundation system composed of stone columns and piles grouped together under a rigid raft foundation in compressible soil. The failure mechanism of this hybrid foundation system was examined, and configurations optimizing the performance of the combined foundation system were explored. An analytical model was developed for predicting the ultimate carrying capacity of the combined system in compressible soils. It was deduced that combining stone columns and piles in one foundation system improved considerably the system’s carrying capacity. Moreover, the uppermost improvement was observed when the piles were installed on the periphery or edge of the raft foundation, while stones columns were placed at the center area of the raft. The failure of the combined foundation system started from the center of the raft and noticeably extended to its edges. Due to the presence of stone columns in the combined foundation system, the piles did not interact. The areas affected or influenced by the soil–pile interaction also did not overlap.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

564. Global DNA methylation in rats´ liver is not affected by hypercholesterolemic diet

Creator:
Jurcikova-Novotna, Lucie , Mrazova, Lenka , Mičová, Kateřina , Friedecký, David , Hubacek, Jaroslav A., and Poledne, Rudolf
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
rat, cholesterol, diet, liver, and DNA methylation
Language:
English
Description:
Increased plasma cholesterol levels are listed between the major atherosclerosis risk factors. The final plasma cholesterol levels result from the interplay between the genetic and environmental (diet, physical activity) factors. Little is known, how dietary factors influence epigenetics. We have analyzed, if an overgeneration feeding of rat with cholesterol influences total liverDNA methylation, and if total liver-DNA methylation differ between the different rat strains (Prague hereditary hypercholesterolemic rats, Prague hereditary hypertriglyceridemic rats and Wistar Kyoto rats). The animals were feed with high fat (additional 5 % over normal capacity) high cholesterol (2 %) diet for 14 days. DNA methylation in the liver tissue in different generations was analyzed using the liquid chromatography coupled with tandem mass spectrometry. We have not observed any significant changes in total liver-DNA methylation over the 9 generations of animals feed by fat/cholesterol enriched diet. Additionally, there were no differences in DNA methylation between different rat strains. In animal model, the dietary changes (hypercholesterolemic diet) not significantly influence the total DNA methylation status within the liver.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

565. Global, macro, and personal impacts on Latvia: a latent structure of perceived control

Creator:
Kolesovs, Aleksandrs and Ruza, Aleksejs
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
perceived impact, latent structure, globalization, threats, Latvia, personal control, vnímaný dopad, latentní struktura, globalizace, hrozby, Lotyšsko, and osobní vliv
Language:
Czech
Description:
The study explores a latent structure of perceived impacts on the country. Perceived controllability of the context shapes individual plans and forms resource for dealing with changes. The direct and indirect exposure to global challenges (e.g., terrorist attacks) can change individual views of the controllability of the context and lead to negative psychological consequences. On the basis of the analysis, a set of perceived impacts was included in the investigation – impacts on a person, people of Latvia, its political institutions, and global players and threats – as factors representing different levels of ecological systems. Six hundred forty-seven university students from Riga, Valmiera, and Daugavpils participated in the study. The Future of Country Questionnaire was modified and used for the assessment of perceived impacts on Latvia. Exploratory and confirmatory factor analyses provided evidence for four main factors representing perceived impacts: personal control, political power, globalization, and global threats. The latter factor involved military tension and terrorism. Revealed links between control beliefs confirmed the interconnectedness of sub- and super-ordinated ecological systems. Cooperation with other people can facilitate the sense of controllability of the macro-societal context. and Tato studie zkoumá latentní strukturu vnímaných dopadů na stát. Vnímaná ovladatelnost kontextu dotváří jednotlivé plány a formuje zdroje pro vyrovnávání se se změnami. Přímé a nepřímé vystavení globálním výzvám (např. teroristickým útokům) může změnit individuální pohled na kontrolovatelnost kontextu a vést k negativním psychologickým důsledkům. Na základě této analýzy byla do šetření zahrnuta sada zkoumaných vnímaných dopadů – na danou osobu, obyvatele Lotyšska, politické instituce a globální aktéry a hrozby, coby faktory reprezentující různé úrovně vnějších systémů. Studie se zúčastnilo 647 univerzitních studentů z Rigy, Valmiery a Daugavpils. K hodnocení vnímaných vlivů na Lotyšsko byl použit modifikovaný dotazník Budoucnost země. Exploratorní a konfirmační faktorová analýza podpořila čtyři hlavní faktory reprezentující vnímané dopady: osobní kontrolu, politickou moc, globalizaci a globální hrozby, přičemž poslední faktor zahrnoval vojenské napětí a terorismus. Zjištěné souvislosti přesvědčení o kontrolovatel­nosti potvrdily provázanost mezi podřízenými a nadřízenými vnějšími systémy. Spolupráce s ostatními lidmi může posílit pocit vlivu (kontroly).
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

566. Glucocorticoids affect male testicular steroidogenesis

Creator:
Hampl, Richard and Stárka, Luboslav
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
glukokortikoidy, stres (fyziologie), apoptóza, glucocorticoids, stress (physiology), apoptosis, HPG axis, leydig cell, 14, and 612
Language:
English
Description:
Through their receptors at each level of hypothalamo-pituitarygonadal axis glucocorticoid excess, either endogenous or administered or stress-induced, could affect steroid production in the testis and thus male fertility. The main ways by which glucocorticoids act are as follows: 1) Affecting gonadoliberin and LH synthesis and release through glucocorticoid receptors in hypothalamic neurons and pituitary gonadotropes. 2) By so far not clearly evidenced reduction of the number of LH receptors on the membrane of Leydig cells. 3) By affecting expression and function of steroidogenic enzymes in the testis. 4) By regulation of in situ access of glucocorticoid to its target cells in the testis. 5) By promotion Leydig cell apoptosis. The review provides a survey of physiological and molecular mechanisms staying behind these effects. It does not deal with the clinical effects of glucocorticoid treatment which would substantially exceed the scope of the pater., Richard Hampl, Luboslav Stárka., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public