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4414. Estimates of seasonal signals in GNSS time series and environmental loading models with iterative least-squares estimation (ILSE) approach

Creator:
Kaczmarek, Adrian and Kontny, Bernard
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
geodynamika, geomechanika, geofyzika, geologie, geodynamics, geomechanics, geophysics, geology, wavelet analysis, seasonal signal, coordinates time series, loading models, phase shift, cross-correlation, correlation coefficient, 7, and 551
Language:
English
Description:
The GNSS (Global Navigation Satellite System) coordinates time series are still used as a source for determining the velocities of GNSS permanent stations. These coordinates, apart from the geodynamical signals, also contain an interference signal. This paper shows the results of the comparative analysis of the GNSS coordinates time series with a deformation of the Earth's crust obtained from loading models. In the analysis, coordinates time series are used (CODE Repro2013) without loading models (Atmospheric Pressure Loading, Hydrology, Non-Tidal Ocean Loading) at the stage of the reprocessing of GNSS archival data. The analyses showed that in the case of the Up component there is a high correlation between the GNSS coordinates changes and deformations of the Earth's crust from the loading models (coefficient 0.5-0.8). Additionally, we noticed that for horizontal components (North, East) changes occur in the phase shift between coordinates, and the Earth’s crust deformations signals are accelerated or delayed each other (-150 to 200 days). This article shows new methods of iLSE (iteration Least Square Estimation) to determine periodic signals in the time series. Additionally, we compared the values of estimated amplitudes for GNSS and deformation time series. and Kaczmarek Adrian, Kontny Bernard.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

4415. Estimation of apparent L-amino acid diffusion in porcine jejunal enterocyte brush border membrane

Creator:
Fan, M. Z., Adeola, O., and Asem, E. K.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, aminokyseliny, difuze, prasata, amino acids, diffusion, pigs, enterocyte, brush border membrane vesicles, 14, and 612
Language:
English
Description:
There is an overlap of carrier-mediated L-amino acid transport and apparent simple diffusion when measured in intestinal brush border membrane vesicles. Using L-threonine and L-glutamine as representative amino acids, this study was undertaken to estimate apparent simple diffusion of L-amino acids and to establish the effective dosage of HgCl2 for completely blocking carrier-mediated L-amino acid transport in porcine jejunal enterocyte brush border membrane vesicles. Jejunal mucosa was scraped from three pigs weighing 26 kg. Enterocyte brush border membrane vesicles, with an average enrichment of 24-fold in sucrase specific activity, were prepared by Mg2+-precipitation and differential centrifugation. In vitro uptake was measured by the fast filtration manual procedure. HgCl2 blocked the carrier-mediated initial transport of L-threonine and L-glutamine under Na+-gradient condition in a dose-dependent manner. At the minimal concentration of 0.165 mmol HgCl2 mg-1 protein, carrier-mediated L-threonine and L-glutamine transport was completely inhibited. The apparent L-threonine and L-glutamine diffusion was estimated to be 8.6±0.7 and 12.4±1.0 % of the total uptake at the substrate concentrations of 5 mM (L-threonine) and 50 mM (L-glutamine). Therefore, the treatment of porcine brush border membrane vesicles with a minimum of 0.165 mmol HgCl2 mg-1 protein completely blocks carrier-mediated L-amino acid transport and enables the direct estimation of apparent L-amino acid diffusion in enterocyte brush border membrane vesicles., M. Z. Fan, O. Adeola, E. K. Asem., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4416. Estimation of genetic affinities between sympatric populations of Rhipicephalus pusillus ticks (Acari: Ixodidae) by analysis of cuticular hydrocarbons

Creator:
Estrada-Peňa, Agustín, Osácar, Juan J., Calvete, Carlos, and Estrada-Peňa, Rosa
Format:
print
Type:
model:internalpart and TEXT
Subject:
Rhipicephalus pusillus, ticks, cuticular hydrocarbons, and genetic similarity
Language:
English
Description:
Genetic distances and phylogenetic clustering are calculated for sympatric populations of Rhipicephalus pusillus (Gil Collado) 1939 ticks, using cuticular hydrocarbon analysis and several statistical tools (stepwise discriminant analysis, Nei’s genetic distance using different sets of compounds, and Cavalli-Sforza’s Brownian motion model). Discriminant analysis on genic frequencies permits the detection of the most ancient geographic relationships between the populations, while the genetic distance method determines current evolutive affinities. However, methods based on quantitative estimation provide a poor resolution. Genetic distances are very high in the populations studied, suggesting a strong reproductive isolation of the specimens involved.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4417. Estimation of sub-diurnal noise level in GPS time series

Creator:
Bogusz, Janusz and Kontny, Bernard
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, GPS (navigační systém), šum, GPS (navigation system), noise, short-time solutions, ASG-EUPOS, 7, and 551
Language:
English
Description:
This paper contains the studies of the noise level in GPS (Global Positioning System) time series. As the data for this research the authors used changes of the geodetic coordinates of the ASG-EUPOS and associated (Slovak and Czech) sites. The method of precise GPS observations processing in short-time intervals was worked out in the Centre of Applied Geomatics, Military University of Technology. The authors focus on the diurnal and sub-diurnal frequency bands (tidal) as the tidal effects influence the sites’ positions at the most and the model used in the standard processing software does not contain geodetic coefficients. Thus the residual values of the geodetic coordinates time series should hold some information in the shape of coloured noise. The paper comprise short description of the Earth tides phenomenon, the concept of the tidal parameters determination, character of the white and coloured noise and the assessment of the noise estimation from GPS data. As the processed network contains 130 sites the spatial distribution of the noise’s parameters is also investigated., Janusz Bogusz and Bernard Kontny., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4418. Estimation of the stressed state of the rock mass in the area of the Outokumpu deep drill hole (OKU), Finland

Creator:
Savchenko, Stepan and Gorbatsevich, Feliks
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, skály, rocks, Poisson’s ratio, elasticity modulus, deep drilling, stressed state, Outokumpu, 7, and 551
Language:
English
Description:
The stressed state of the rock mass in the area of the Outokumpu deep drill hole, Finland, was investigated by the boundaryelement method in three mutually orthogonal planes with regard for the massif geological structure. It was found that subhorizontal components of the stress field are determined by tectonic forces acting on the boundaries of the European part of the Eurasian lithospheric plate. In the drill hole vertical section the widest variations of this field gradient occur at the depths of an ophiolite sequence in the range of 1.8-2.0 km., Stepan Savchenko and Feliks Gorbatsevich., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4419. Estrogen can modulate menopausal women's heart rate variability

Creator:
Yang, S.-G., Mikuláš Mlček, and Otomar Kittnar
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, menopauza, hormonální substituční terapie, srdeční rytmus, menopause, hormone replacement therapy, heart rate, heart rate variability, 14, and 612
Language:
English
Description:
b1_The aim of our study was to compare the responses of heart rate variability (HRV) with two di fferent types of hormonal substitution therapy (HT) in post-menopausal women (cross-sectional study) and to reveal an effect of HT shortly after beginning of its administration (f ollow-up study). To elucidate the influence of menopause and effects of different protocols of a HT on autonomic control of heart rate, we evaluated the heart rate variability (HRV) in 5 groups: premenopausal women (n=140), postmenopausal women without HT (n=360), women on HT with conjugated estrogen only (n =168), women on continuous combined estrogen-progesterone HT (n=117), and men (n=140). Frequency-domain of short-term stationary R-R intervals was performed to evaluate the total variance, low frequency power (LF; 0.04-0.15 Hz), high freque ncy power (HF; 0.15-0.40 Hz), portion of low frequency power (LF%) and ratio of LF to HF (LF/HF). Significantly lower portion of the LF was found in premenopausal women [46.9 (±2.7) nu] when compared to untreated postmenopausal wome n [54.3 (±2.9) nu] and men [55.2 (±3.0) nu]. Treatment by estrogen only was proved to decrease the LF% [40.1 (±2.1) nu] while no effect on HRV was observed in women treated with combination of estrogen and progesterone [57.2 (±3.1) nu]. Also the HF was lower in postmenopausal wome n [4.16 (±0.16) ms 2 ] than in premenopausal women [4.79 (±0.22) ms 2 ] and women treated with estrogen only [4.98 (±0.25) ms 2 ] while in women treated with combined hormonal therapy the average value [3.99 (±0.21) ms 2 ] did not significantly differ from that of untreated postmenopausal women. The follow-up study also proved increase of high frequency power already after two months of estrogen substitution therapy [4.86 (±0.14) ms 2 vs. 4.19 (±0.15) ms 2 ]., b2_These results suggest that hi gher vagal modulation of heart rate that seems typical for younger women becomes after menopause similar to that of men. We also proved a positive shift of HRV parameters toward more beneficial values as for a cardiovascular risk in postmenopausal women treated with estrogens but not in those treated by combined estrogen - progesterone substitution therapy., S.-G. Yang, M. Mlček, O. Kittnar., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4420. Estrogen effect on some enzymes of female rats after downhill running

Creator:
Sotiriadou, S., Kyparos, A., Mougios, V., Trontzos, Ch., Sidiras, G., and Matziari, Ch.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, estrogeny, estrogens, eccentric exercise, muscle damage, 14, and 612
Language:
English
Description:
The study investigates the effect of administered estrogen on plasma creatine kinase (CK) and lactate dehydrogenase (LD) levels in female ovariectomized rats after downhill running. Rats ovariectomized before sexual maturity were subcutaneously implanted with pellets containing 17β-estradiol or placebo. Three weeks later they were subjected to a 90-min intermittent downhill running protocol. Blood samples were obtained from the jugular vein immediately after and 72 h after exercise for determination of plasma CK, LD and 17β-estradiol levels. A two-way analysis of variance was used for data evaluation. Plasma CK and LD levels were significantly lower (p<0.05) in the estrogen-supplemented, ovariectomized animals which suggests that less muscle damage occurred compared to the controls immediately and 72 h after exercise. Estrogens may have a protective effect on muscle tissue possibly due to their antioxidant and membrane stabilizing properties., S. Sotiriadou, A. Kyparos, V. Mougios, Ch. Trontzos, G. Sidiras, Ch. Matziari., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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