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9392. Solar excitation of bicentenni al earth rotation oscillations
- Creator:
- Cyril Ron, Chapanov, Yavor, and Jan Vondrák
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, zemská rotace, sluneční aktivita, Earth rotation, solar activity, 7, and 551
- Language:
- English
- Description:
- The bicentennial varia tions of the Earth rotation consist of several oscill ations with most known periods 178.7a (Jose cycle), 210a and 230a (de Vries cycle); they are driven by the solar cycles which affect climatic variations, followed by global environmental changes. These periods are close to the higher harmonics of millennial Hallstatt cycle (2300a), so the proper separation between the indi vidual bicentennial cycles needs time series longer than 2300a. The bicentennial variations of the Universal Time (UT1) in relation to the Terrestrial Time (TT) are investigated using reconstructed time series of the Total Solar Irradiance (TSI) for the last 9300a. A linear regression model of TSI influe nce on the UT1 and the Mean Sea Level (MSL) bicentennial variations are created. The parameters and time series of the bicentennial UT1-TT oscillations for the last 9300a are determined., Cyril Ron, Yavor Chapanov and Jan Vondrák., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9393. Sollár, T.: Empirická verifikácia štrukturálnych modelov psychodiagnostických nástrojov
- Creator:
- Jozef Džuka
- Format:
- print, bez média, and svazek
- Type:
- article, recenze, model:article, and TEXT
- Subject:
- Psychologie, psychologie, psychology, 17, and 159.9
- Language:
- Czech
- Description:
- [autor recenze] J. Džuka.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9394. Soluble leptin receptor levels in patients with chronic renal failure
- Creator:
- Jarmila Křížová, Sylvie Sulková, Vladimíra Bednářová, Jana Pařízková, Eva Kotrlíková, and Martin Haluzík
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, leptin, anorexie, anorexia, soluble leptin receptor, chronic renal failure, 14, and 612
- Language:
- English
- Description:
- Soluble leptin receptor (SLR) is the extracellular part of the leptin receptor. This protein is released into circulation and constitutes the main circulating leptin-binding protein. The aim of our study was to measure SLR concentrations in patients with chronic renal failure (CRF) and healthy subjects and to explore the relationship of SLR to other hormones and cytokines. The patients with CRF had significantly higher serum leptin, TNF-a and insulin levels than healthy subjects (25.1±23.5 vs. 9.4±7.6 ng.ml-1 (S.D.); 14.2±4.2 vs. 4.55±2.5 ng.ml-1; 39.8±36.1 vs. 20.3±11.1 mU.l-1). Serum soluble leptin receptor levels did not differ between these groups (19.1±11.3 vs. 19.6±6.1 U.ml-1). An inverse relationship between serum SLR and leptin levels was found in both groups. In patients with CRF the inverse relationship between SLR and insulin, body fat content and total protein levels were also found, while in healthy subjects only inverse relationship of SLR with insulin and albumin concentrations were detected. We conclude that soluble leptin receptor levels in patients with chronic renal failure do not differ from those of healthy subjects despite higher serum leptin levels in CRF patients. The physiological consequences of this finding require further investigation., J. Křížová, S. Sulková, V. Bednářová, E. Kotrlíková, M. Haluzík., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9395. Solute patterns and diurnal variation of photosynthesis and chlorophyll fluorescence in Korean coastal sand dune plants
- Creator:
- Hwang, J.-S. and Choo, Y.-S.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Korea, fyziologická adaptace, výměna plynu, fluorescence chlorofylu, nonstomatal limitation, osmotic adjustment, physiological adaptation, stomatal limitation, gas exchange, chlorophyll fluorescence, 2, and 581
- Language:
- Multiple languages
- Description:
- Four plant species, Elymus mollis Trin., Carex kobomugi Ohwi, Glehnia littoralis F. Schmidt ex Miq., and Vitex rotundifolia L.f., are dominant perennial species in coastal sand dunes of Korea. We examined a physiological adaptation of these species by measurements of diurnal variation in photosynthesis and chlorophyll (Chl) fluorescence and solute patterns in leaves during one season (June), which is favorable for plant growth of all four species. All four species adopted different strategies in order to utilize radiation and to maintain water status under a fluctuating microclimate. Although the lowest water contents among four plant species was found, E. mollis with a high Chl and K+ content showed better photosynthetic performance, with high stomatal conductance (gs), net photosynthetic rate (PN), instantaneous carboxylation efficiency (CE), and water-use efficiency. Midday depression of PN in E. mollis and G. littoralis, without a reduction of gs, was associated with a reduction in CE and maximum photochemical efficiency of PSII, indicating nonstomatal limitation. Photosynthesis depression in both C. kobomugi and V. rotundifolia, with relatively low gs values, could be attributed to both stomatal and nonstomatal limitations. The high storage capacity for inorganic ions in E. molli, C. kobomugi, and G. littoralis may play an efficient role in regulating photosynthesis and maintaining leaf water status through stomatal control, and can also play an important role in osmotic adjustment., J.-S. Hwang, Y.-S. Choo., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9396. Somatotropin has no effect on the quantity of guanine nucleotide binding proteins Gqalpha/G11alpha in goat adipose tissue in vivo
- Creator:
- Krbeček, V., Hana Kovářů, Josef Škarda, Tomislav Barth, Jiří Velek, and Žižkovský, V.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, tuková tkáň, kozy, adipose tissue, goats, samatotropin, g-proteins, 14, and 612
- Language:
- English
- Description:
- The decapeptide QLNLKEYNLV corresponding to the C-terminus of Gq/G11alpha guanine nucleotide-binding proteins (G-proteins) was synthesized by the solid-phase method and conjugated to keyhole limpet hemocyanin. The rabbits were immunized with these conjugates and an antiserum that reacted specifically with the alpha subunit of Gq/G11 proteins was used in this study. The antiserum exhibited no cross-reactivity with the alpha subunits of stimulatory (Gs) or inhibitory (Gi) G-proteins associated with adenylate cyclase. Immunoblots with the antiserum showed that it specifically recognized the Gq/G11 alpha-proteins in cholate extracts of adipose tissue membranes of goats. Treatment of young castrated male goats with bST had no effect on the quantity of Gq/G11 alpha-subunits in adipose tissue and the results thus obtained did not support the idea that the bST signal in adipose tissue is transmitted via Gq/G11 alpha-proteins., V. Krbeček, H. Kovářů, J. Škarda, T. Barth, J. Velek, V. Žižkovský., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9397. Some current insights into oxidative stress
- Creator:
- Zdeňka Ďuračková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, antioxidanty, oxidační stres, antioxidants, oxidative stress, reactive metabolites, redox stress, signaling, 14, and 612
- Language:
- English
- Description:
- Oxidative stress is a phenomenon associated with pathogenetic mechanisms of several diseases including atherosclerosis, neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, cancer, diabetes mellitus, inflammatory diseases, as well as psychological diseases or aging processes. Oxidative stress is defined as an imbalance between production of free radicals and reactive metabolites, so-called oxidants, and their elimination by protective mechanisms, referred to as antioxidative systems. This imbalance leads to damage of important biomolecules and organs with potential impact on the whole organism. Oxidative and antioxidative processes are associated with electron transfer influencing the redox state of cells and the organism. The changed redox state stimulates or inhibits activities of various signal proteins, resulting in a changed ability of signal pathways to influence the fate of cells. At present, the opinion that oxidative stress is not always harmful, has been accepted. Depending on the type of oxidants, intensity and time of redox imbalance as well as on the type of cells, oxidative stress can play a role in the regulation of other important processes through modulation of signal pathways, influencing synthesis of antioxidant enzymes, repair processes, inflammation, apoptosis and cell proliferation, and thus processes of malignity. Imprudent administration of antioxidants may therefore have a negative impact on the organism., Z. Ďuračková., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9398. Some endocrine traits of transgenic rabbits. II. Changes in hormone secretion and response of isolated ovarian tissue to FSH and ghrelin
- Creator:
- Alexander V. Sirotkin, Peter Chrenek, Darlak, K., Valenzuela, F., and Kuklová, Ž.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Experimentální medicína, biotechnologie, transgenoze, progesteron, biotechnology, transgenosis, progesterone, FSH, ghrelin, estradiol, IGF-1, 14, and 616-092
- Language:
- English
- Description:
- In the present in vitro experiments we examined FSH- and ghrelin-induced changes in ovarian hormone secretion by transgenic rabbits. Fragments of ovaries isolated from adult transgenic (carrying mammary gland-specific mWAP-hFVIII gene) and non-transgenic rabbits from the same litter were cultured with and without FSH or ghrelin (both at 0, 1, 10 or 100 ng/ml medium). The secretion of progesterone (P4), estradiol (E2) and insulin-like growth factor I (IGF-I) was assessed by RIA. It was observed that ovaries isolated from transgenic rabbits secreted much less P4, E2 and IGF-I than the ovaries of non-transgenic animals. In control animals FSH reduced E2 (at doses 1-100 ng/ml medium) and IGF-I (at 1-100 ng/ml), but not P4 secretion, whereas ghrelin promoted P4 (at 1 ng/ml) and IGF-I (at 100 ng/ml), but not E2 output. In transgenic animals, the effects were reversed: FSH had a stimulatory effect on E2 (at 100 ng/ml) and ghrelin had an inhibitory effect on P4 (at 10 ng/ml). No differences in the pattern of influence of FSH on P4 and IGF-I and of ghrelin on E2 and IGF-I were found between control and transgenic animals. The present observations suggest that 1) both FSH and ghrelin are involved in rabbit ovarian hormone secretion, 2) transgenesis in rabbits is associated with a reduction in ovarian secretory activity, and 3) transgenesis can affect the response of ovarian cells to hormonal regulators., A. V. Sirotkin, P. Chrenek, K. Darlak, F. Valenzuela, Ž. Kuklová., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9399. Some factors which influence the in vitro maintenance of Anisakis simplex (Nematoda)
- Creator:
- Iglesias, Luis, Valero, Adela, and Adroher, Francisco-Javier
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Anisakis simplex, culture media, survival, and moulting
- Language:
- English
- Description:
- Several culture media as well as some factors that may affect the in vitro development of the nematode Anisakis simplex Rudolphi, 1809 have been studied. After testing six media and four temperatures, the conditions for the in vitro culture selected were as follows: RPML1640 + 20% (v/v) heat-inactived fetal bovine serum or Meyer’s М3 (without agar) media, at 37"C, under 5% C02 in air atmosphere, and renewal of the medium twice a week. The average survival rates of the larvae were significantly increased when the pH of the culture medium was increased (from 4.0 to 7.2) or decreased (from 7.2 to 4,0) after L, to L4 moulting. The length of the larvae at the onset of culture affected the survival and moulting of themselves, but these were culture medium-dependent. On the other hand, we have observed that several L, and L, were attached, by means of a brown unknown substance apparently secreted by themselves, to the bottom of the substratum. Frequently, when a larva was spontaneously detached, a “cap” of the brown substance blocked, apparently, its mouth. The possible absorption of nutrients through the L, larvae cuticle of A. simplex is discussed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9400. Some features of seismic waves observed in the territory of Northern Moravia and Silesia
- Creator:
- Holub, Karel, Jaromír Knejzlík, Růžek, Bohuslav, Rušajová, Jana, and Oldřich Novotný
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, zemětřesení, seizmicita, earthquake, seismicity, body waves, surface waves, quarry blast, microearthquake, crustal structure, Moravo-Silesian region, 7, and 551
- Language:
- English
- Description:
- A grant project for the period 2003-2005, supported by the Grant Agency of the Czech Republic, was set up to determine properties of seismic waves and the structure of the uppermost part of the Earth´s crust in the territory of northern Moravia and Silesia. Quarry blasts and mining induced seismic events served as seismic sources. Permanent, temporary and portable seismic stations were used for the monitoring of these seismic events. During the experiments local microearthquakes were also detected and localized. For the complex evaluation of seismic wave features, data of the CELEBRATION 2000 and SUDETES 2003 refraction experiments were incorporated, as well. The velocity-depth dependence of body waves was searched by joint inversions of travel times of Pg/Sg phases. A special feature of the wave trains, generated by quarry blasts, was a pronounced dispersive character of short-period Rayleigh surface waves. These waves enabled us to establish their dispersion curves, on the basis of which the structure of superficial layers was determined down to a depth of several hundreds of meters., Karel Holub, Jaromír Knejzlík, Bohuslav Růžek, Jana Rušajová and Oldřich Novotný., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public