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14752. Changes in direct CO2 and N2O emissions from a loam Haplic Luvisol under conventional moldboard and reduced tillage during growing season and post-harvest period of red clover
- Creator:
- Horák, Ján, Igaz, Dušan, Aydin, Elena, Šimanský, Vladimír, Buchkina, Natalya, and Balashov, Eugene
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tillage systems, soil organic matter, temperature, moisture content, water-filled pore space, and CO2 and N2O emissions
- Language:
- Slovak
- Description:
- The objectives of the study were to: (1) assess the strength of associations of direct CO2 and N2O emissions with the seasonal variations in the relevant soil properties under both tillage systems; 2) evaluate how CT and RT affect magnitudes of seasonal CO2 and N2O fluxes from soil. Field studies were carried out on plots for conventional tillage (up to 0.22–0.25 m) and reduced tillage (up to 0.10–0.12 m) during the growing season and post-harvest period of red clover. The results showed that daily CO2 emissions significantly correlated only with soil temperature during the growing season under conventional and reduced tillage. Soil temperature demonstrated its highest influence on daily N2O emissions only at the beginning of the growing season in both tillage systems. There were no significant inter-system differences in daily CO2 and N2O emissions from soil during the entire period of observations. Over the duration of post-harvest period, water-filled pore space was a better predictor of daily CO2 emissions from soils under CT and RT. The conventional and reduced tillage did not cause significant differences in cumulative N2O and CO2 fluxes from soil.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14753. Changes in effects of ozone exposure on growth, photosynthesis, and respiration of Ginkgo biloba in Shenyang urban area
- Creator:
- He, X.-Y., Fu, S.-L., Chen, W., Zhao, T.-H., Xu, S., and Tuba, Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carboxylation efficiency, chlorophyll, dark respiration, gas exchange, intercellular CO2 concentration, leaf area index, non-stomatal limitations, photorespiration, stomatal conductance, and transpiration rate
- Language:
- Multiple languages
- Description:
- An open-top chamber experiment was carried out from April through October 2006 to examine the effects of elevated (80 nmol mol-1) atmospheric O3 on Ginkgo biloba (4-years-old) in urban area. The air with ambient O3 (AA, ≈ 45 nmol mol-1) was used as control. The leaf mass and size, leaf area index, net photosynthetic rate (PN), apparent quantum yield, transpiration rate, and stomatal conductance were decreased by elevated O3 (EO) exposure. Visible foliar injury, which is light-brown flecks, was observed in the EO OTCs after 90 d of exposure. Carboxylation efficiency (ΦCO2) and photorespiration and dark respiration rates were enhanced by EO exposure in the first half of the season, but all of them turned to be lower than those of the AA control at the end of experiment. Stomata limitation of photosynthesis was significantly higher than control in the whole season (p<0.05). Chlorophyll (Chl) content was lower in EO variant than in the control and the difference became more and more apparent through the season. Hence the decrease in PN of G. biloba exposed to EO was the result of both stomatal and non-stomatal limitations. In the early season, the inhibition of photosynthesis was mainly caused by the stomatal limitation, and the earliest response was photoprotective down-regulation of photosynthesis but not photodamage. However, at the end of the season, the non-stomatal limiting factors such as decrease in Chl content, decrease in ΦCO2, and anti-oxidative enzyme activity became more important. and X.-Y. He ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14754. Changes in electron transport, superoxide dismutase and ascorbate peroxidase isoenzymes in chloroplasts and mitochondria of cucumber leaves as influenced by chilling
- Creator:
- Hu, W. H., Song, X. S., Shi, K., Xia, X. J., Zhou, Y. H., and Yu, J. Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ascorbate peroxidase, Cucumis sativus, net photosynthetic rate, photosynthetic electron transport, quantum efficiency, reactive oxidative metabolism, respiratory electron transport, respiration pathways, and superoxide dismutase
- Language:
- Multiple languages
- Description:
- In order to clarify the relationship between chill-induced disturbance in photosynthetic, respiratory electron transport and the metabolism of reactive oxygen species (ROS), leaf gas exchange, chlorophyll fluorescence quenching, respiration, and activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX) were investigated in chloroplasts and mitochondria of cucumber (Cucumis sativus) leaves subjected to a chill (8 °C) for 4 d. Chilling decreased net photosynthetic rate (PN) and quantum efficiency of photosystem 2 (ΦPS2), but increased the ratio of ΦPS2 to the quantum efficiency of CO2 fixation (ΦCO2) and non-photochemical quenching (NPQ) in cucumber leaves. While chilling inhibited the activity of cytochrome respiration pathway, it induced an increase of alternative respiration pathway activity and the reduction level of Q-pool. Chilling also significantly increased O2* production rate, H2O2 content, and SOD and APX activities in chloroplasts and mitochondria. There was a more significant increase in SOD and APX activities in chloroplasts than in mitochondria with the increase of membrane-bound Fe-SOD and tAPX in chloroplasts being more significant than other isoenzymes. Taken together, chilling inhibited PN and cytochrome respiratory pathway but enhanced the photosynthetic electron flux to O2 and over-reduction of respiratory electron transport chain, resulting in ROS accumulation in cucumber leaves. Meanwhile, chilling resulted in an enhancement of the protective mechanisms such as thermal dissipation, alternative respiratory pathway, and ROS-scavenging mechanisms (SODs and APXs) in chloroplasts and mitochondria. and W. H. Hu ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14755. Changes in expenditure and income inequality: an examination of the micro data (1989 vs. 1992)
- Creator:
- Garner, Thesia, Martina Lubyová, and Katherine Terrell
- Publisher:
- CERGE-EI
- Format:
- print, svazek, and 18 stran : tabulky.
- Type:
- model:monograph and TEXT
- Subject:
- Národní hospodářství a hospodářská politika, 1989, 1992, příjmy, individuální spotřeba, income, consumption (economics), Česko, Slovensko, Czechia, Slovakia, 330.564.2, 330.567.22, (437.3), (437.6), (048.8), 4, and 330.5+338
- Language:
- English
- Description:
- Thesia Garner, Martina Lubyová and Katherine Terrell. and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14756. Changes in Extracellular Space Volume and Geometry Induced by Cortical Spreading Depression in Immature and Adult Rats
- Creator:
- Tomáš Mazel, Richter, F., Lýdia Vargová, and Eva Syková
- Format:
- print, bez média, and svazek
- Type:
- article, studie, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Cell swelling, Cortex, Diffusion, Spreading depression, Extracellular space, 14, and 612
- Language:
- English
- Description:
- Changes in extracellular space (ECS) diffusion parameters, DC potentials and extracellular potassium concentration were studied during single and repeated cortical spreading depressions (SD) in 13-15 (P13-15), 21 (P21) and 90-day-old (adult) Wistar rats. The real-time iontophoretic method using tetramethylammonium (TMA+)-selective microelectrodes was employed to measure three ECS parameters in the somatosensory cortex: the ECS volume fraction α (α = ECS volume/total tissue volume), ECS tortuosity λ (increase in diffusion path length) and the nonspecific TMA+ uptake k’. SD was elicited by needle prick. SD was significantly longer at P13-15 than at P21 and in adults. During SD, α in all age groups decreased from 0.21-0.23 to 0.05-0.09; λ increased from 1.55-1.65 to 1.95-2.07. Ten minutes after SD, α (in adults) and λ (all age groups) increased compared to controls. This increase persisted even 1 hour after SD. When SD was repeated at 1 hour intervals, both α and λ showed a gradual cumulative increase with SD repetition. Our study also shows that cortical SD is, as early as P13, accompanied by severe ECS shrinkage and increased diffusion path length (tortuosity) with values similar to adults, followed by a long-lasting increase in ECS volume and tortuosity when compared to pre-SD values., T. Mazel, F. Richter, L. Vargová, E. Syková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14757. Changes in FGF21 serum concentrations and liver mRNA expression in an experimental model of complete lipodystrophy and insulin-resistant diabetes
- Creator:
- Špolcová, A., Holubová, M., Mikulášková, B., Nagelová, V., Štofková, A., Zdeňka Lacinová, Jana Jurčovičová, Martin Haluzík, Lenka Maletínská, and Železná, B.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, inzulinová rezistence, játra, insulin resistance, liver, FGF21, A-ZIP mice, lipodystrophy, fatty liver, GLUT-1, 14, and 612
- Language:
- English
- Description:
- Patients with obesity and type 2 diabetes often display high levels of the anti-diabetic factor fibroblast growth factor-21 (FGF21), suggesting that the overproduction of FGF21 may result from increased adiposity in an attempt by white adipose tissue (WAT) to counteract insulin resistance. However, the production of FGF21 diabetes in the absence of WAT has not been examined. In this study, we investigated the effects of lipodystrophy in A-ZIP F-1 mice on FGF21 production in relation to diabetes. A-ZIP F-1 mice displayed high FGF21 plasma levels resulting from enhanced FGF21 mRNA expression in the liver. Concomitant enhancement of FGF21 receptor (FGFR1) and glucose transporter 1 (GLUT-1) mRNA expression was observed in the muscles of A-ZIP F-1 mice. Furthermore, the activation of hypothalamic NPY and AgRP mRNA expression positively correlated with plasma levels of FGF21 but not active ghrelin. Our study demonstrates that an increased FGF21 plasma level in lipodystrophic A-ZIP F-1 mice results mainly from up-regulated liver production but does not suffice to overcome the lipodystrophy-induced severe type 2-diabetes and insulin resistance in the liver linked to the augmented liver fat deposition., A. Špolcová, M. Holubová, B. Mikulášková, V. Nagelová, A. Štofková, Z. Lacinová, J. Jurčovičová, M. Haluzík, L. Maletínská, B. Železná., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14758. Changes in heart rate variability in patients with atrial fibrillation after pulmonary vein isolation and ganglionated plexus ablation.
- Creator:
- Vesela, J. , Osmancik, P. , Herman, D., and Prochazkova, R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- atrial fibrillation, ablation, heart rate variability, and ganglionated plexus
- Language:
- English
- Description:
- Pulmonary vein isolation (PVI) is the cornerstone in the treatment of patients with paroxysmal atrial fibrillation (PAF). Some research has suggested studies have shown that modification of ganglionated plexuses (GP), performed with PVI, could lead to even better outcomes. The aim of this study was to determine the effect of PVI on the autonomic system. Heart rate variability (HRV) was used as a marker of autonomic system activity. Twenty-six PAF patients underwent PVI (PVI group) and twenty patients underwent PVI plus a GP ablation (GP group). In each group, 5 min long ECG signals obtained before and after the electrophysiology EP study were analyzed. Time and frequency domain parameters were evaluated. Vagal responses during ablation were observed in 15 (58 %) patients in the PVI group and in 12 (60 %) patients in the GP group. The change in normalized power in the low frequency (LF) and in the LF/HF ratio, before and after ablation, was statistically significant in both groups (LF/HF 2.6±1.6 before vs. 1.4±1.7 after ablation in PVI group and LF/HF 3.3±2.6 before vs. 1.8±1.9 after ablation in the GP group). Relative to heart rate variability parameters, there were no differences between PVI and PVI + plus GP ablation.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14759. Changes in hind paw epidermal thickness, peripheral nerve distribution and mechanical sensitivity after immobilization in rats
- Creator:
- Nakano, J., Sekino, Y., Hamaue, Y., Sakamoto, J., Yoshimura, T., Origuchi, T., and Okita, M.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, immobilization, hypersensitivity, skin, epidermal thickness, peripheral nerve, 14, and 612
- Language:
- English
- Description:
- This study was designed to investigate histological changes in skin tissue accompanying immobilization-induced hypersensitivity. Changes in mechanical sensitivity, epidermal thickness, and peripheral nerve profiles in the upper dermis were examined in glabrous skin of rat hind paw after 1, 2, and 4 weeks of ankle joint immobilization by plaster casts. Induction of mechanical hypersensitivity was confirmed after 2 and 4 weeks of joint immobilization. Epidermal thinning and increase in peripheral nerve profiles were observed in skin tissues in immobilized rats. The time course of epidermal thinning and increase in peripheral nerve profiles were similar closely to that of hypersensitivity, with significant differences between the immobilized and control rats after 2 weeks of immobilization, which became even more remarkable at 4 weeks of immobilization. These findings suggest that joint immobilization by cast induces epidermal thinning and increases peripheral nerve profiles in the upper dermis and that these changes might be partly responsible for immobilization-induced hypersensitivity., J. Nakano, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14760. Changes in leaf photosynthesis of transgenic rice with silenced OsBP-73 gene
- Creator:
- Chen, Y. and Xu, D.-Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carboxylation efficiency, intercellular CO2 concentration, net photosynthetic rate, photochemical efficiency, Oryza, ribulose-1,5-bisphosphate (RuBP), ribulose-1,5-bisphosphate carboxylase, oxygenase (RuBPCO), RNA interference, RuBP regeneration limitation, and stomatal conductance
- Language:
- Multiple languages
- Description:
- In comparison with its wild type (WT), the transgenic (TG) rice with silenced OsBP-73 gene had significantly lower plant height, grain number per panicle, and leaf net photosynthetic rate (PN). Also, the TG rice showed significantly lower chlorophyll (Chl), ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO), RuBPCO activase, and RuBP contents, photosystem 2 (PS2) photochemical efficiency (Fv/Fm and ΔF/Fm'), apparent quantum yield of carbon assimilation (Φc), carboxylation efficiency (CE), photosynthetic electron transport and photophosphorylation rates as well as sucrose phosphate synthase activity, but higher intercellular CO2 concentration, sucrose, fructose, and glycerate 3-phosphate contents, and non-photochemical quenching of Chl fluorescence (NPQ). Thus the decreased PN in the TG rice leaves is related to both RuBP carboxylation and RuBP regeneration limitations, and the latter is a predominant limitation to photosynthesis. and Y. Chen, D.-Q. Xu.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public