The channel network at this region was built up for drainage and also to provide irrigation water. The water level in the whole channel network system affect groundwater level and viceverse. From the view of mutual interaction between channel network and groundwater it has been necessary to assess impact of channel network silting on this interaction. The measurements of thickness of silts along three main channels were carried out in 1993. Then in 2004 there were done measurements in selected profiles along three channels: Aszód, Gabčíkovo-Topoľníky and Komárňanský channel. The paper shows changes in measured thickness and volume of silt in particular channels. It was shown the channel silting up has not been changed significantly during the monitored period. This fact is documented by graphical presentation of silt thicknesses of channels. The differences between silt top and channel bottom levels are presented. and Obsahom príspevku je hodnotenie zmien stavu kanálovej siete Žitného Ostrova z hľadiska zanesenia kanálov dnovými nánosmi v období rokov 1993 až 2004. Kanálová sieť bola vybudovaná v tomto regióne v priebehu 19. storočia jednak na čiastočné odvodnenie územia a zároveň na zabezpečenie závlah. Hladina vody v kanáloch ovplyvňuje výšku hladiny podzemnej vody v ich okolí a naopak. Z hľadiska procesu vzájomnej interakcie kanálovej siete s okolitou podzemnou vodou je nevyhnutné venovať pozornosť vplyvu zanášania kanálov dnovými nánosmi, keďže tieto môžu v značnej miere tento proces ovplyvňovať. V roku 1993 boli merané zanesenia kanálovej siete ŽO na vopred stanovených priečnych profiloch niektorých hlavných kanálov. V priebehu rokov 2004 boli vykonané kontrolné merania zanesenia vo vybraných profiloch kanálov Aszód, Gabčíkovo-Topoľníky a Komárňanského kanála. Tieto kontrolné merania sa robili vždy v úseku na začiatku, v strede a na konci jednotlivých kanálov, pretože sa uvažovalo s predpokladom lineárnych zmien hrúbok nánosov pozdĺž kanálov. Grafickými prílohami príspevok dokumentuje skutočnosť, že v priebehu sledovaného obdobia nedošlo k podstatným zmenám zanesenia kanálovej siete. Keďže pre účely príspevku sú dôležité hrúbky nánosov (teda rozdiely medzi dnom kanála a vrchom nánosovej vrstvy), bolo postačujúce, aby kontrolné merania boli robené od hladiny a neboli vztiahnuté na nadmorské výšky.
In the paper a sequential monitoring scheme is proposed to detect instability of parameters in a multivariate autoregressive process. The proposed monitoring procedure is based on the quasi-likelihood scores and the quasi-maximum likelihood estimators of the respective parameters computed from a training sample, and it is designed so that the sequential test has a small probability of a false alarm and asymptotic power one as the size of the training sample is sufficiently large. The asymptotic distribution of the detector statistic is established under both the null hypothesis of no change as well as under the alternative that a change occurs.
This paper deals with the changeover from the decision tree (bivalent logic) approach to the fuzzy logic approach to highway traffic control, particularly to variable speed limit displays. The usage of existing knowledge from decision tree control is one of the most suitable methods for identification of the new fuzzy model. However, such method introduces several difficulties. These difficulties are described and possible measures are proposed. Several fuzzy logic algorithms were developed and tested by a~microsimulation model. The results are presented and the finest algorithm is recommended for testing on the Prague City Ring Road in real conditions. This paper provides a~guidance for researchers and practitioners dealing with similar problem formulation.
Matrix metalloproteinases (MMPs) play an important role in the pathogenesis of heart failure (HF). Our aim was to determine the activities of circulating MMP-2 and MMP-9 in patients with HF in respect of gender, comorbidities and treatment (n=51). We did not reveal any differences in circulating pro-MMP-2 and pro-MMP-9 activities between the patients with HF and without it. However, there was a decrease in activity of pro-MMP-2 in treated hypertensive participants versus healthy ones. In contrast, we observed increased pro-MMP-2 activity in hypertensive participants with coexistent HF versus hypertensive participants without HF. In addition, a decrease in pro-MMP-2 activity was shown in women suffering from HF versus men suffering from HF. In conclusion, potential inhibitory effect of antihypertensive treatment on pro-MMP-2 activity was found. Coexistent HF with hypertension probably reduces the inhibitory effect of antihypertensive treatment on pro-MMP-2 activity. Our data also suggest the role of potential cardioprotective factors influencing the activity of pro-MMP-2 in women., E. Giannakos, E. Vardali, M. Bartekova, M. Fogarassyova, M. Barancik, J. Radosinska., and Obsahuje bibliografii
Acute phase proteins and markers of proteosynthetic activity reflect the clinical activity in Crohn´s disease (CD). The impact of anti-tumor necrosis factor antibody (anti-TNF) therapy on serum levels of acute phase proteins and proteosynthetic markers was studied. Fourteen patients with active CD were treated with 5 mg per kg of anti-TNF in intravenous infusion. Clinical activity (assessed by Crohn´s disease activity index - CDAI), α-1-acid glycoprotein, haptoglobin, cholinesterase and prealbumin were assessed before and in months 1 and 5 after treatment. A sustained decrease in CDAI was observed. This was accompanied by a significant decrease in α-1-acid glycoprotein and haptoglobin in month 1 (p=0.005 and p=0.01, respectively) while in month 5 the levels of both acute phase proteins rose significantly (p=0.003 for α-1-acid glycoprotein and p=0.02 for haptoglobin). Cholinesterase and prealbumin significantly increased in month 1 after the treatment (p=0.02 and p=0.0006, respectively), the increase was sustained in cholinesterase while prealbumin levels diminished in month 5. We conclude that the clinical improvement after anti-TNF therapy for CD is accompanied by changes of acute phase proteins and proteosynthetic markers. The assessment of these laboratory markers may be useful in the management of CD patients treated with anti-TNF., V. Kupčová, L. Turecký, Z. Detková, M. Príkazská, A. Keleov., and Obsahuje bibliografii
Performances and reliability of a human operator are influenced by
fatigue. Influence of fatigue on the human operátor - car driver as a controller in the steering control loop is discussed. Demonstrated are possibilities of fatigue identification from small compensatory movernents of the steering wheel. Preliminary results of using a fatigue indicator based on the analysis of compensatory movernents of the steering wheel are introduced.
Its high oxidant capacity and ability to generate reactive oxygen species cause ozone toxicity. We studied the effect of ambient ozone on chlorophyll (Chl) a fluorescence, antioxidant enzymes, ascorbate contents, and lipid peroxidation in potatoes grown in open-top chambers in the field. In plants grown in non-filtered air (NFA), the development of non-photochemical quenching brought about a decrease in photosystem 2 (PS2) photochemical efficiency. Also the ability of PS2 to reduce the primary acceptor QA was lower than in charcoal-filtered, ozone-free air (CFA). Changes in Chl fluorescence yield were associated with changes in the thylakoid membrane. Ozone altered chloroplast membrane properties, as indicated by an increase in membrane lipid peroxidation in FNA-leaves compared to CFA plants. The ascorbate pool and activities of antioxidant enzymes were used for an indication of the detoxification system state in NFA and CFA leaves, whereby ozone affects the ascorbate concentration and decreases the antioxidant enzymes activities. The capacity of both detoxifying systems together was not high enough to protect potato plants against ambient ozone concentrations which reduced the photosynthetic yield in this potato cultivar. and A. Calatayud, J. W. Alvarado, E. Barreno.
The effects of drought and the diurnal changes in photosynthetic electron transport were studied in non-nodulated plants of Casuarina equisetifolia. The induction of fluorescence showed a slightly higher I step in water-stressed than control plants, and the time from the start of irradiation to the P step of induction was significantly shortened by drought. The quantum efficiency of photosystem 2 (PS2) in the dark-adapted state (Fv/Fm) was generally not affected by drought, whereas it decreased during the central hours of the day. The decrease in quantum yield of PS2 electron transport (Φ2) in water-stressed plants was associated with decreases in the photochemical efficiency of open (oxidised) PS2 centres (Fv'/Fm') and increases in non-photochemical quenching (qN) rather than with increased closure of PS2 centres (lowered photochemical quenching, qP). In contrast, the changes in quantum yield of electron transport during the day were related to changes in qP rather than in Fv'/Fm'. When chlorophyll fluorescence was measured at the same irradiance during the day, a greater qN was observed at the end of the drying cycle than after watering, and early and late in the photoperiod than in the central hours of the day. The greater qN at the beginning and end of the day did not prevent an increase in energy not used photochemically nor dissipated non-photochemically. Drought did not affect this excess of photon energy. and R. Martínez-Carrasco, J. Sánchez-Rodriguez, P. Pérez.
The size, shape, and number of chloroplasts in the palisade and spongy parenchyma layers of Haberlea rhodopensis leaves changed significantly during desiccation and following rehydration. The chloroplasts became smaller and more rounded during desiccation, and aggregated in the middle of the cell. The size and number of chloroplasts in the palisade parenchyma cells were higher than in spongy parenchyma. The good correlation observed between the size or number of chloroplasts and the cross-sectional area of mesophyll cells, the cross-sectional width of the leaf and its water content suggested that the palisade cells were more responsive to water availability than the spongy cells. Changes in chloroplast number during desiccation and rehydration process are characteristic features for desiccation-tolerant plants (especially in homoiochlorophyllous strategy). and H. Nagy-Déri ... [et al.].
Chloroplasts are commonly the site of the earliest abiotic injury visible in plant ultrastructure. In this study, six inbred lines of maize (Zea mays L.) were used to analyze changes in the ultrastructure of chloroplasts and related physiological parameters under conditions of drought stress simulated by 20% polyethylene glycol 6000 (-0.6 MPa) for two days. Chloroplasts of three maize lines proved to be more sensitive. They showed changes in the ultrastructure in response to drought, including damage of thylakoid membranes, an increase in the number and size of plastoglobuli, swelling of thylakoid membranes both stromal and granal, disorganization of the thylakoid membrane system, an obvious increase in the intrathylakoid space, and a decrease in the
length-to-width ratio and area of chloroplasts. In addition, the contents of malondialdehyde increased markedly in the sensitive lines. Contrary to the sensitive lines, stable structures and shapes of chloroplasts were observed in the drought-resistant lines; it could be considered as an advantage contributing to drought tolerance in the plants. In addition, the drought index of leaf fresh mass (LMDI) in the drought-sensitive lines was ≤ 0.5, which was also associated with a lower content of leaf chlorophyll. In contrast, drought tolerance coincided with lesser growth reduction, and higher LMDI and leaf chlorophyll content., R. X. Shao, L. F. Xin, H. F. Zheng, L. L. Li, W. L. Ran, J. Mao, Q. H. Yang., and Obsahuje seznam literatury