Purpose. The aim of the paper was to determine the effect of respiration on body balance in quiet standing. Basic procedures. Postural performance during quiet standing was compared in 37 young healthy subjects in two trials on a force plate: first with natural breathing, and then with accelerated high-volume breathing at the rate of 1 Hz. Each trial included 20 s quiet standing with eyes open, and the center of pressure (COP) was recorded with the sampling rate of 20 Hz in both anterior-posterior (AP) and mediallateral (ML) planes. Based on the recorded signals the COP dispersion measures and postural frequency were calculated. Main findings. The forced respiration contributed significantly to the increase in all COP stability measures in the AP plane: dispersion (p < 0.01), range (p < 0.001) and mean velocity and frequency (p < 0.00001). In the ML plane only mean velocity (p < 0.001) and frequency (p < 0.01) were affected. Conclusions. In view of the evidence provided by other authors that stress tests increase the amplitude- and frequency-based stability measures, our results indicate that the contribution of natural accelerated breathing after strenuous physical exercise will bias the results of stabilographic studies, rendering them worthless in understanding the role of neuromuscular fatigue in stability deterioration. Such studies must use data collected after the respiration returns to normal rate. However, if the study aims at overall assessment of postural stability post-fatigue, the postural testing may be performed immediately after the stress test.
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The main focus of this research was to apply Metabolic Control Analysis to quantitative investigation of the regulation of respiration by components of the Mitochondrial Interactosome (MI, a supercomplex consisting of ATP Synthasome, mitochondrial creatine kinase (MtCK), voltage dependent anion channel (VDAC), and tubulin) in permeabilized cardiomyocytes. Flux control coefficients (FCC) were measured using two protocols: 1) with direct ADP activation, and 2) with MtCK activation by creatine (Cr) in the presence of ATP and pyruvate kinase-phosphoenolpyruvate system. The results show that the metabolic control is much stronger in the latter case: the sum of the measured FCC is 2.7 versus 0.74 (ADP activation). This is consistent with previous data showing recycling of ADP and ATP inside the MI due to the functional coupling between MtCK and ANT and limited permeability of VDAC for these compounds, PCr being the major energy carrier between the mitochondria and ATPases. In physiological conditions, when the MI is activated, the key sites of regulation of respiration in mitochondria are MtCK (FCC = 0.93), adenine nucleotide translocase ANT (FCC = 0.95) and CoQ cytochrome c oxidoreductase (FCC = 0.4). These results show clearly that under the physiological conditions the energy transfer from mitochondria to the cytoplasm is regulated by the MI supercomplex and is very sensitive to metabolic signals.
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The organic matter production/respiration balance in the coastal water column was examined, both the primary production and community respiration being measured with the oxygen light-and-dark bottle method. Community respiration (CR) was always lower than the gross primary production (GPP) measured at a standard light intensity of 390 žE m-2 s-1, which amounted, on average, to 30% of GPP. During most of the in situ sampling period, the coastal system (6-7 m depth) was found to be autotrophic, with depth-integrated GPP ranging from 6.7 mmoles O2 m-2 d-1 in December to 214.2 mmoles O2 m-2 d-1 in August, and CR ranging correspondingly from 6.0 to 177.7 mmoles O2 m-2 d-1. However, on some occasions heterotrophic conditions were recorded: depth-integrated GPP
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Plant respiratory chain branches at the level of ubiquinone from where the electrons flow through the cytochrome pathway or to alternative oxidase. Transfer of electrons from ubiquinone to oxygen by alternative oxidase has a non-protonmotive character and, by bypassing two sites of H+ pumping in complexes III and IV, lowers the energy efficiency of respiration. In this paper we review theoretical and experimental studies about the structure and possible function of alternative oxidase. The evidence for specific gene expression dependent on the physiological, developmental and environmental conditions is also described. We underline the physiological role of alternative oxidase as a "survival" protein that allows plants to cope with the stressful environment.
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A facility of BaPS (Barometric Process Separation) and indoor incubation experiments were used to determine the effect of soil salinity on soil respiration and nitrogen transformation. The rates of soil respiration, gross nitrification, denitrification, ammonium and nitrate nitrogen concentrations and relevant soil parameters were measured. Results showed that soil respiration and nitrification and denitrification rates were all affected by soil salinity. Furthermore, the effect of soil salinity level on nitrification and denitrification rates had a threshold value (EC1:5 = 1.13 dS/m). When soil salinity level was smaller to this threshold value, the rates of nitrification and denitrification increased with soil salinity while they were reduced when soil salinity level was larger than the threshold value. Moreover, the changing law of soil respiration rate with soil salinity was similar with the nitrification and denitrification rates while the variation tendency was opposite. In addition, the transformation form urea to ammonium and nitrate nitrogen was also reduced with the increase of soil salinity and the reduced effect could be expressed by exponential functions.
PL
Proces BaPS (Ciśnieniowy Proces Separacji) oraz inkubacja pokojowa zostały wykorzystane do określenia wpływu zasolenia gleby na jej oddychanie i transformację azotu. Mierzono szybkości: respiracji gleby, całkowitej nitryfikacji i denitryfikacji, a także stężenie azotu amonowego i azotanowego oraz wartości odpowiednich parametrów gleby. Wyniki wykazały, że respiracja glebowa oraz szybkości nitryfikacji i denitryfikacji były uzależnione od zasolenia gleby. Ponadto stwierdzono, że wpływ poziomu zasolenia gleby na szybkość nitryfikacji i denitryfikacji miał wartość progową (EC1:5 = 1,13 dS/m). Gdy poziom zasolenia gleby był mniejszy od tej wartości progowej, szybkości nitryfikacji i denitryfikacji rosły wraz ze wzrostem zasolenia gleby. Jeżeli zasolenie gleby był większe od progowego, to szybkości te malały. Co więcej, zmiany charakteru zależności szybkości respiracji gleby od jej zasolenia były porównywalne z szybkością nitryfikacji i denitryfikacji, podczas gdy tendencja zmian była odwrotna. Ponadto, transformacja mocznika do amoniaku i azotu azotanowego również zmniejszała się przy wzroście zasolenia gleby, a efekt takiego zmniejszania może być wyrażony funkcją wykładniczą.
The effect of toxic metal - cadmium on twa representants, the medicinal plant Hypericum perforatum L. and green alga Chlorella vulgaris Beijer bas been studied. We investigated the effect of cadmium (12 [mu]M Cd(N03)2; pH = 5.5) on growth, plant biomass (root and shoot) and root dark respiration rate of H. perforatum as well as cadmium accumulation in all plant organs. The highest Cd concentration was found in the root (1792 [mu]g g^-1 d.w.) which was 8-times higher concentration that in the stem and 6-times higher than in the leaves. The effect of cadmium treatment on the content of iron, manganese and carrer in individual plant organs bas been also determined. Cd administration did not affect the growth and dry biomass of the shoot and root and the root : shoot ratio. However, the root dark respiration rate of the Cd-treated plants was faster than those of the control plants. The interaction of cadmium with chlorophyll a situated in pigmentprotein complexes of photosynthetic centres of H. perforatum chloroplasts bas been confirmed by fluorescence spectroscopy. Cadmium inhibited the growth, łatał chlorophyll and carotenoids content in statically cultivated Chlorella vulgaris (7d, 16h light/8h dark). The production of chlorophyll a in algae was affected more pronouncedly than that of chlorophyll b and consequently the ratio of Chl a : Chl b showed a decrease with the increasing of cadmium concentration.
PL
Zbadano wpływ toksycznego metalu - kadmu na dwie rośliny: roślinę leczniczą - Hypericum perforatum L. i algę zieloną - Chlorella vulgaris Beijer. Badano wpływ kadmu (12 [mu]M Cd(N03)2; pH = 5,5) na wzrost, biomasę roślin (korzenia i pędu) oraz tempo ciemnej respiracji korzenia H. perforatum, jak również akumulacje kadmu we wszystkich organach roślinnych. Największe stężenie kadmu stwierdzono w korzeniu (1792 [mu]g g^-1 s.m.) i było ono 8 razy większe niż stężenie w łodydze i 6 razy większe niż w liściach. Oznaczano także wpływ traktowania kadmem na zawartość żelaza, manganu i miedzi w poszczególnych organach. Traktowanie kadmem nie miało wpływu na rozrost i suchą biomasę pędu i korzenia oraz na stosunek masy korzenia do pędu. Jednakże szybkość ciemnej respiracji korzenia roślin traktowanych kadmem było szybsze niż miało to miejsce w przypadku roślin kontrolnych. Potwierdzono także, za pomocą spektroskopii fluorescencyjnej, interakcje pomiędzy kadmem a chlorofilem a znajdującym się w białku pigmentowym kompleksów centrów fotosyntetycznych chloroplastów H. perforatum. Kadm inhibował wzrost, zawartość całkowitą chlorofilu i karotenoidów w statycznie hodowanych Chlorella vulgaris (7d, 16 h światła/8 h ciemności). Oddziaływanie kadmu na produkcję chlorofilu a w algach było znacznie wyraźniejsze niż na produkcję chlorofilu b i w rezultacie stosunek Chl a : Chl b malał wraz ze wzrostem stężenia kadmu.
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The study was conducted on an experiment established in the area of the former Sulphur Mine “Jeziorko.” The remediation was applied to a soil-less formation with particle size distribution of weakly loamy sand, strongly acidified and with bad sorptive properties (Corg. - 2.0 g kg−1; pHKCl - 4.3; T - 7.0 cmol(+) kg−1). In the particular treatments of the experiment the following were applied to the soil-less formation: flotation lime and NPK; lime and sewage sludge; sewage sludge; mineral wool (5 cm 50 cm−1), lime and NPK; mineral wool (5 cm 50 cm−1), lime and sewage sludge; mineral wool (500 m3 ha−1), lime and NPK; mineral wool (500 m3 ha−1), lime and sewage sludge. Plots prepared in that manner were then sown with a mix of grasses. The control was the soil with no amendments. The analyses of the soil material comprised assays of the numbers of particular groups of bacteria and fungi, and of their biochemical and enzymatic activities. The study revealed that all the wastes applied for the remediation caused an increase in the numbers of the bacterial groups studied (copiotrophic, oligotrophic, cellulolytic, lipolytic), as well as in the respiration activity and rate of mineralisation of cellulose. That effect was the most pronounced in the case of sewage sludge. In treatments in which sewage sludge was applied, an increase was also observed in the numbers of the studied fungi (fungi on Martin medium, cellulolytic fungi, lipolytic fungi) and in lipase activity. Whereas, the application of the remaining wastes resulted in a slight decrease in the numbers of the fungal groups under analysis. Comparing the mean annual values of the analysed biological, physical, chemical and physicochemical properties it was found that the biological properties were as sensitive, and in the case of certain tests (numbers of cellulolytic and lipolytic bacteria, rate of cellulose mineralisation) even more sensitive indicators of positive changes taking place in the remediated soil.
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