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29142. Temperature-dependent gas exchange and stomatal/non-stomatal limitation to CO2 assimilation of Quercus liaotungensis under midday high irradiance
- Creator:
- Zhang, Shouren, Li, Qingkang, Ma, Keping, and Chen, Lingzhi
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- carboxylation rate, diurnal course of gas exchange, internal CO2 concentration, photosynthesis, stomatal conductance, transpiration rate, and water use efficiency
- Language:
- Multiple languages
- Description:
- The effects of varying leaf temperature (T1) on some ecophysiological characteristics of photosynthesis for Quercus liaotungensis Koiz. under ambient radiation stress around midday on clear summer days were investigated using an IRGA equipped with a temperature-controlled cuvette. Net photosynthetic rate (PN) decreased as T1 increased from 30 to 35 °C as a result of stomatal closure, whereas non-stomatal limitation led to decreased PN in the T1 range of 35-45 °C. Decreased transpiration rate (E) and stomatal conductance (gs) at leaf temperatures above 30 °C were interpreted as a combined 'feedward' effect as a result of enhanced leaf-air vapour pressure deficit (VPD) and stomatal closure. Changes in E from T1 30 to 20 °C depended on VPD when gs was maintained constant. Water use efficiency (WUE) varied inversely with T1 by following a hyperbola. A decrease in intercellular CO2 concentration (Ci) occurred as a result of stomatal closure and a relatively high carboxylation capacity, whereas inactivation of mesophyll carboxylation in combination with photorespiration might be associated with the observed increase in Ci in the T1 range of 40 to 45 °C. and Shouren Zhang ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29143. Templeton, D. M. (ed.): Molecular and cellular iron transport
- Creator:
- Šesták, Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- iron
- Language:
- Multiple languages
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29144. Templetonova cena za sblížení vědy a náboženství
- Creator:
- Grygar, Jiří
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29145. Temporal and spatial distribution of glochidial larval stages of European unionid mussels (Mollusca: Unionidae) on host fishes
- Creator:
- Blažek, Radim and Gelnar, Milan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- glochidia, seasonality, host specificity, gill and fin parasites, and freshwater mussel
- Language:
- English
- Description:
- Glochidia are the larval stage of freshwater unionid mussels that parasitize the fins and gill apparatus of fish. A total of 22 fish species were examined for the presence of glochidia whose distribution on individual hosts was studied on three common fish species, the roach Rutilus rutilus (L.), perch Perca fluviatilis L. and bitterling Rhodeus sericeus (Pallas). Between 1997 and 1999, the fish were obtained from the rivers Morava and Kyjovka and surrounding water pools in the Czech Republic. The glochidia of two genera, Unio and Anodonta, were found. Anodonta glochidia were observed on 10 fish species, Unio glochidia on 17 fish species. There was a difference in spatial distribution of glochidia on the body of the host fish. Unio glochidia were predominantly located on the gills, whereas most Anodonta glochidia were found on the fins, with the highest numbers of glochidia were observed on the margin of the pectoral fins. For the gill apparatus, Unio glochidia were found predominantly on the second and third arch. Anodonta glochidia were predominantly found during winter and spring (November-May), whereas Unio glochidia were more abundant during May and June. The number of glochidia was positively correlated with fish length in perch highly infected by Anodonta glochidia and perch infected by Unio glochidia. Of the three fish species, the highest occurrence of parasites was found on perch with fewer observed on roach. In spite of the close relationship between bitterling and unionid mussels, glochidiosis was rare on this fish species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29146. Temporal and spatial expression of podocyte-associated molecules are accompanied by proteinuria in IgA nephropathy rat model
- Creator:
- Lu, H.-Y., Chen, L.-Z., Jiang, X.-Y., Mo, Y., Ling, Y.-H., and Sun, L.-Z.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, IgA nephropathy, proteinuria, podocyte, nephrin, podocin, desmin, 14, and 612
- Language:
- English
- Description:
- We used a rat model to assess the role of nephrin, podocin, and desmin in the pathogenesis of IgA nephropathy (IgAN). A rat IgAN model was established by administration of BSA, CCl4, and lipopolysaccharide (LPS) and compared with healthy control rats. Urinary protein, urine red blood cells, and biochemical parameters were measured for 12 weeks. Renal morphology and ultrastructure were examined by light and electron microscopy. Immunofluorescence was used to assess IgA deposition in the glomeruli and to measure expression of nephrin, podocin, and desmin. Real-time quantitative PCR was used to measure expression of nephrin, podocin, and desmin mRNAs. IgAN rats developed proteinuria at week-6 and this worsened over time. Pathological changes were evident under light microscopy at week-8 and under electron microscopy at week-4. Immunofluorescence analysis showed deposition of IgA in the kidneys of IgAN rats, but not control rats. IgAN rats had increased expression of glomerular podocin, nephrin, and desmin mRNAs and proteins at week-4. The expression of nephrin, podocin and desmin proteins and the expression of podocin and desmin mRNAs preceded the increase in urinary protein. Taken together, our study of a rat model of IgAN indicates that changes in the expression and distribution of nephrin, podocin, and desmin precede and may cause foot process fusion and proteinuria., H.-Y. Lu, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29147. Temporal and spatial patterns of the river flow and water temperature relations in Poland
- Creator:
- Wrzesiński, Dariusz and Graf, Renata
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- river flow, water temperature, hydrological regime, correlation coefficient, hierarchical clustering, and Central Europe
- Language:
- Slovak
- Description:
- Main aim of the study was to determine the temporal and spatial patterns of relations between monthly and annual average river flow (RF) and water temperature (WT) for 53 rivers in Poland. The research made use of monthly and annual WT and RF for 88 water gauges for the period 1971–2015. Correlations were established using the Spearman’s rank correlation coefficient and the similarity of RF–WT relations was determined using the Ward’s hierarchical grouping. It was demonstrated that correlations between average annual RF and WT were negative (for >85% of water gauges) and statistically significant (p<0.05) only for 30% of water gauges. It was confirmed that the studied RF–WT relations underwent seasonal changes. Positive correlations were clearly predominant in the winter months, while from April to September these relations were negative and statistically significant. The RF–WT relations were also characterized by spatial differences and this had been confirmed by separation of seven groups of water gauge profiles distinguished with the help of the Ward's hierarchical grouping method. The strongest RF–WT relations were apparent in the case of mountainous rivers, for which snow melt supply and summer rainfall supply were predominant, and lakeland rivers, which had a considerable share of groundwater supply. These were classified as cold rivers, as opposed to the cool rivers in the lowland belt, for which the RF–WT relations were the weakest. The results obtained may contribute to the elaboration of an appropriate management strategy for river ecosystems, which are assigned important economic and environmental functions.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29148. Temporal changes in soil water erosion on sloping vineyards in the Ruwer-Mosel Valley: The impact of age and plantation works in young and old vines
- Creator:
- Rodrigo-Comino, Jesús, Brings, Christine, Iserloh, Thomas, Casper, Markus C., Seeger, Manuel, Senciales, José M., Brevik, Eric C., Ruiz-Sinoga, José D., and B. Ries, Johannes
- Type:
- article, model:article, and TEXT
- Subject:
- soil erosion, old vineyard, young vineyard, rainfall, tillage, and Ruwer-Mosel valley
- Language:
- Slovak
- Description:
- It is well known that rainfall causes soil erosion in sloping German vineyards, but little is known about the effect of age of plantation on soil erosion, which is relevant to understand and design sustainable management systems. In the Ruwer-Mosel valley, young (1- to 4-years) and old (35- to 38-years after the plantation) vineyards were selected to assess soil and water losses by using two-paired Gerlach troughs over three years (2013–2015). In the young vineyard, the overland flow was 107 L m–1 and soil loss 1000 g m–1 in the year of the plantation, and decreased drastically over the two subsequent years (19 L m–1; 428 g m–1). In the old vineyard, soil (from 1081 g m–1 to 1308 g m–1) and water (from 67 L m–1 to 102 L m–1) losses were 1.2 and 1.63 times higher, respectively, than in the young vineyard.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
29149. Temporal changes in the abundance of barbel, Barbus barbus in the Jihlava River, Czech Republic
- Creator:
- Peňáz, Milan, Pivnička, Karel, Baruš, Vlastimil, and Prokeš, Miroslav
- Type:
- article and TEXT
- Subject:
- capture-recapture, electrofishing, aurvival, and tagging
- Language:
- English
- Description:
- A four-year experiment with a total of 993 individually-tagged barbel, Barbus barbus, resulted in the assessment of survival and abundance. The mean annual survival rate was 0.862, but the partial values assessed separately for seasons (spring – autumn and autumn – spring) differed considerably and the possible reasons for this phenomenon are discussed. On the basis of known survival rate, the abundance was subsequently estimated (for the entire studied stretch and per hectare) using the Petersen capture-recapture method for the period spring 1999 to autumn 2002, and the mean value reached 303 ± 110 ind.ha-1 (minimum 195, maximum 498 ind.ha-1). The Jolly-Seber method was also used to estimate abundance from autumn 1999 to spring 2001 and gave a mean 425 ± 120 ind.ha-1 and a range 233–563 ind.ha1. These results were in autumn 2001 supported by another simultaneously conducted census following the removal method by Zippin (316 ind.ha-1). The abundance showed a significant tendency to increase during the four-year survey, which is in an accordance with the long-term changes observed in the dynamics of the fish community in this stream.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
29150. Temporal characteristics of chlorophyll fluorescence quenching and dissolved oxygen concentration as indicators of photosynthetic activity in Chlorella emersonii
- Creator:
- El Khachia, N.-E., O'Mongain, E., and Collins, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- algal blooms, DCMU, non-photochemical quenching, photosystem 2, and zero oxygen tablets
- Language:
- Multiple languages
- Description:
- A simple chlorophyll fluorescence (CF) measuring system has been implemented to study temporal characteristics of chlorophyll fluorescence induction (CFI) in dark-adapted freshwater algal cultures of Chlorella emersonii. There were two different decay time constants describing the CF quenching: τ0 (the faster) and τ1 (the slower) with amplitudes A0 and A1, respectively. The relative amplitude of the faster quenching component decreased once the sample was subject to deprivation from dissolved oxygen (DO). The DO concentration of samples was monitored to validate the effects of deprivation from air contact for up to 7 d and to the effect of adding DCMU to the culture (herbicide for blocking electron transport of photosystem 2). CFI analysis and DO measurements showed that the relative amplitude of A0 to (A0 + A1) and the DO concentration can be used as an indication of relative photosynthetic activity, thus allowing for the possibility to classify the physiological state of algal blooms into active and inactive states. and N. E. El Khachia, E. O'Mongain, A. Collins.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public