Two teak (Tectona grandis L.f.) phenotypes differing in their leaf length/breadth ratios were subjected to water stress by withholding water supply for three weeks. Growth rates of whole plants, developing leaves (1st and 2nd from shoot apices), and 2nd and 3rd internodes were higher in broad leaved (BL) phenotype than in narrow leaved (NL) phenotype before and after imposing water stress treatment. However, the effect of water stress on these parameters was higher in the BL phenotype than in the NL one. Diurnal course of net photosynthetic rate (PN) of 3rd or 4th leaves from shoot apices measured under well-watered conditions was higher for the NL than BL phenotype. PN, stomatal conductance (gs), and transpiration rate (E) in both phenotypes were negatively affected by water stress and their decline under water stress was significantly higher in the BL than NL plants. and G. Rajendrudu, C. V. Naidu, K. Mallikarjuna.
Three-month-old mulberry (Morus alba L.) cultivars (drought tolerant S13 and drought sensitive S54) were subjected to water stress for 15 d. Water stress decreased the leaf water potential, net photosynthetic rate (PN), and stomatal conductance (gs) in both the cultivars. However, the magnitude of decline was comparatively greater in the sensitive cultivar (S54). Intercellular CO2 concentration (Ci) was unaltered during mild stress, but significantly increased at severe stress in both cultivars. The photosystem 2 activity significantly declined only at a severe stress in both cultivars. The Ci/gs ratio representing the mesophyll efficiency was greater in the tolerant cultivar S13. Involvement of stomatal and/or non-stomatal components in declining PN depended on the severity and duration of stress. However, the degree of non-stomatal limitations was relatively less in the drought tolerant cultivar. and S. Ramanjulu, N. Sreenivasulu, C. Sudhakar.
In order to evaluate effect of weedy rice on the photosynthesis and grain filling of cultivated rice, cultivated rice ‘Nanjing 44‘ was planted in the field under different densities of weedy rice ‘JS-Y1‘ for two years. The results showed that net photosynthetic rate (PN), net assimilation rate, grain filling rate, and the grain yield of cultivated rice all decreased with increasing weedy rice density. Furthermore, yield component analysis revealed that increasing weedy rice density had the most significant effect on the percentage of filled grains and the number of rice panicles. The correlation analyses indicated that the yield of cultivated rice was highly correlated with the net photosynthetic rate and the net assimilation rate. Our results illustrated that high density of weedy rice might cause yield losses in cultivated rice by inhibition of photosynthesis and grain filling., X. M. Xu, G. Li, Y. Su, X. L. Wang., and Obsahuje bibliografii
The aim of this study was to assess the influence of regular daily consumption of white wine on oxidative stress and cardiovascular risk markers. Forty-two healthy male volunteers consumed 375 ml of white wine daily. Each participant provided three venous blood samples (before wine consumption, following the wine consumption period and again a month later). Levels of superoxide dismutase, glutathione peroxidase, reduced glutathione, total antioxidant capacity, total cholesterol, HDL-cholesterol, apolipoprotein A I, apolipoprotein B, triglycerides, paraoxonase 1, C-reactive protein, homocysteine, thiobarbituric acid reactive substances (TBARS) and advanced oxidation protein products (AOPP) were measured. Immediately following the month of white wine consumption there was a significant increase in HDL-cholesterol (p<0.0001), paraoxonase 1 (p<0.001), glutathione peroxidase (p<0.001) and reduced glutathione (p<0.01) levels, a decrease in superoxide dismutase activities (p<0.0001), and a decrease in oxidation protein products (p<0.001) and TBARS (p<0.05) concentrations. However, there was also a clear increase in homocysteine (p<0.0001) after a month of white wine consumption. The results of our non-placebo controlled trial suggest that regular daily white wine consumption is associated not only with both antioxidative and antiatherogenic effects but also with a potentially proatherogenic increase of homocysteine concentrations. and D. Rajdl, J. Racek, L. Trefil, K. Siala.
Time delay in the mediation of ventilation (VE) by arterial CO2 pressure (PaCO2) was studied during recovery from short impulse-like exercises with different work loads of recovery. Subjects performed two tests including 10-s impulse like exercise with work load of 200 watts and 15-min recovery with 25 watts in test one and 50 watts in test two. V . E, end tidal CO2 pressure (PETCO2) and heart rate (HR) were measured continuously during rest, warming up, exercise and recovery. PaCO2 was estimated from PETCO2 and tidal volume (VT). Results showed that predicted arterial CO2 pressure (PaCO2 pre) increased during recovery in both tests. In both tests, VE increased and peaked at the end of exercise. VE decreased in the first few seconds of recovery but started to increase again. The highest correlation coefficient between PaCO2 pre and V . E was obtained in the time delay of 7 s (r=0.854) in test one and in time delays of 6 s (r=0.451) and 31 s (r=0.567) in test two. HR was significantly higher in test two than in test one. These results indicate that PaCO2 pre drives VE with a time delay and that higher work intensity induces a shorter time delay., R. Afroundeh, T. Arimitsu, R. Yamanaka, C. S. Lian, K. Shirakawa, T. Yunoki, T. Yano., and Obsahuje bibliografii
We evaluated the effects of exercise on the vascular constrictor responses to α-adrenergic stimulation in the db/db mice. Twenty male db/db and their age-matched wild-type (WT) mice were exercised (1 hour/day, five days a week). Mice were anesthetized 7 weeks later, thoracic aortae were mounted in wire myograph and constrictor responses to phenylephrine (PE, 1 nM-10 μM) were obtained. Citrate synthase activity measured in the thigh adductor muscle was significantly increased in db/db mice that were exercise trained. Maximal force generated by PE was markedly greater in db/db aortae and exercise did not attenuate this augmented contractile response. Vessels were incubated with inhibitors of nitric oxide synthase (L-NAME, 200 μM), endothelin receptors (bosentan, 10 μM), protein kinase C (PKC) (calphostin C, 5 μM), cyclooxygenase (indomethacin, 10 μM) or Rho-kinase (Y-27632, 0.1 μM). Only calphostin-C normalized the augmented PE-induced constriction in db/db and db/db- exercised mice to that observed in WT (p<0.05). Cumulative additions of indolactam, a PKC activator, induced significantly greater constrictor responses in aortic rings of db/db mice compared to WT and exercise did not affect this response. Our data suggest that the augmented vasoconstriction observed in the aorta of db/db mice is likely due to increased PKC activity and that exercise do not ameliorate this increased PKC-mediated vasoconstriction., M. Khazaei, F. Moien-Afshari, T. J. Kieffer, I. Laher., and Obsahuje bibliografii a bibliiografické odkazy
With increasing opportunities for analyzing large data sources, we have noticed a lack of effective processing in datamining tasks working with large sparse datasets of high dimensions. This work focuses on this issue and on effective clustering using models of artificial intelligence.
The authors of this article propose an effective clustering algorithm to exploit the features of neural networks, and especially Self Organizing Maps (SOM), for the reduction of data dimensionality. The issue of computational complexity is resolved by using a parallelization of the standard SOM algorithm. The authors have focused on the acceleration of the presented algorithm using a version suitable for data collections with a certain level of sparsity. Effective acceleration is achieved by improving the winning neuron finding phase and the weight actualization phase. The output presented here demonstrates sufficient acceleration of the standard SOM algorithm while preserving the appropriate accuracy.
We introduce a new way of computation of time dependent partial differential equations using hybrid method FEM in space and FDM in time domain and explicit computational scheme. The key idea is quick transformation of standard basis functions into new simple basis functions. This new way is used for better computational efficiency. We explain this way of computation on an example of elastodynamic equation using quadrilateral elements. However, the method can be used for more types of elements and equations.
The physiological response of plants to triple foliar biofertilization with cyanobacteria and green algae under the conditions of limited use of chemical fertilizers was investigated. Triple foliar biofertilization with intact cells of Microcystis aeruginosa MKR 0105, Anabaena sp. PCC 7120, and Chlorella sp. significantly enhanced physiological performance and growth of plants fertilized with a synthetic fertilizer YaraMila Complex (1.0, 0.5, and 0.0 g per plant). This biofertilization increased the stability of cytomembranes, chlorophyll content, intensity of net photosynthesis, transpiration, stomatal conductance, and decreased intercellular CO2 concentration. Applied monocultures augmented the quantity of N, P, K in plants, the activity of enzymes, such as dehydrogenases, RNase, acid or alkaline phosphatase and nitrate reductase. They also improved the growth of willow plants. This study revealed that the applied nontoxic cyanobacteria and green algae monocultures have a very useful potential to increase production of willow, and needed doses of chemical fertilizers can be reduced., M. Grzesik, Z. Romanowska-Duda, H. M. Kalaji., and Obsahuje bibliografii
Effects of root treatment with 5-aminolevulinic acid (ALA) on leaf photosynthesis in strawberry (Fragaria ananassa Duch.) plants were investigated by rapid chlorophyll fluorescence and modulated 820 nm reflection using 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) and methyl viologen (MV). Our results showed that ALA treatments increased the net photosynthetic rate and decreased the intercelluar CO2 concentration in strawberry leaves. Under DCMU treatment, trapping energy for QA reduction per PSII reaction center increased greatly, indicating DCMU inhibited electron transfer from QA−. The maximum photochemical efficiency of PSII (Fv/Fm) decreased under the DCMU treatment, while a higher Fv/Fm remained in the ALA-pretreated plants. Not only the parameters related to a photochemical phase, but also that one related to a heat phase remained lower after the ALA pretreatment, compared to the sole DCMU treatment. The MV treatment decreased PSI photochemical capacity. The results of modulated 820 nm reflection analysis showed that DCMU and MV treatments had low
re-reduction of P700 and plastocyanin (PSI). However, the strawberry leaf discs pretreated with ALA exhibited high re-reduction of PSI under DCMU and MV treatments. The results of this study suggest that the improvement of photosynthesis by ALA in strawberry was not only related to PSII, but also to PSI and electron transfer chain., Y. P. Sun, J. Liu, R. X. Cao, Y. J. Huang, A. M. Hall, C. B. Guo, L. J. Wang., and Obsahuje bibliografii