Je rozdiel v sérovej hladine retinol-binding proteinu 4 (RBP4) medzi obéznymi s inzulínovou rezistenciou (IR) bez diabetu voči obéznym s diabetom 2. typu (DM2T) liečených metformínom a neobéznymi zdravými? Metodika: 28 obéznym s inzulínovou rezistenciou, 11 diabetikom 2. typu liečených metformínom a 17 kontrolám sa metódou RIA vyšetrila sérová hladina retinol-binding proteinu 4. Výsledky sa porovnali v rámci skupín a RBP4 sa v skupine s IR a v kontrolnej skupine koreloval s inzulínom. Výsledky: Najvyššiu hladinu RBP4 (561,6 ? 209 ng/ml) mali obézni s IR (IR HOMA 3,9) a najnižšiu obézni diabetici typu 2 liečení metformínom (391,1 ? 133,5 ng/ml; p < 0,01). Kontrolná skupina mala signifikantne nižšiu hladinu RBP4 voči obéznym s IR (452,8 ? 104,6 ng/ml; p < 0,05), ale nesignifikantne vyššiu voči obéznym jedincom s DM2T liečených metformínom (391,1 ? 133,5 ng/ml). RBP4 v sledovanej skupine koreloval s inzulínom r = 0,46 (p < 0,03). Záver: Zvýšenie RBP4 u obéznych cestou spätnej regulácie GLUT4 v adipocytoch prispieva k rozvoju a k zhoršeniu systémovej IR metformín vplyvom na expresiu RBP4 v adipocytoch môže u obéznych aj s MS zlepšovať celkovú inzulínovú senzitivitu a spomaliť nástup manifestného DM. RBP4 by mohol slúžiť aj ako marker zhoršujúcej sa tolerancie glukózy u obéznych., Mária Tajtáková, Z. Semanová, G. Ivančová, and Lit. 26
The paper deals with selected procedures used to calculate the shape of compact nappe during free overfall from a smooth horizontal channel with rectangular cross section. Calculated and measured water surface and velocity conditions in the end section, the level of water surface upstream in front of the end section and the shape of the compact part of an overfall nappe are described for a particular compared case.
Despite the increasing interest in applying composts as soil amendments worldwide, there is a lack of knowledge on short-term effects of compost amendments on soil structural and hydraulic properties. Our goal was to study the effect of compost and vermicompost-based soil amendments on soil structure, soil water retention characteristics, aggregate stability and plant water use efficiency compared to that of mineral fertilizers and food-waste digestate and examine if these effects are evident within a short time after application. We set up a pot experiment with spring wheat using a sandy and a loamy soil receiving either mineral fertilizer (MF); dewatered digestate from anaerobic digestion of food waste (DG), vermicomposted digestate (VC_DG); sewage sludge-based compost (C_SS) and sewage sludge-based vermicompost (VC_SS). We then monitored and calculated the soil water balance components (irrigation, outflow, evaporation, transpiration, and soil water content). At harvest, we measured shoot biomass, soil texture, bulk density, water retention characteristics and aggregate stability. The irrigation use efficiency (IE) and the plant water use efficiency (WUE) were calculated for each treatment by dividing the transpiration and the dry shoot biomass with the amount of water used for irrigation, respectively. For the sandy soil, we used X-Ray computed tomography to visualise the pore system after applying organic amendments and to derive metrics of the pore-network such as its fractal dimension, imaged macroporosity and critical pore diameter. X-Ray tomography indicated that composting and vermicomposting resulted in more complex and diverse porous system and increased soil macroporosity. The increased fractal dimensions also indicated that compost and vermicompost can contribute to structure formation and stabilization within a short time after their application. Despite the small application rate and short incubation time, the application of organic amendments to the two different soil types resulted in improved soil water holding capacity and water use efficiency. Composting and vermicomposting appeared to have the best effect at reducing the irrigation demand and evaporation losses and increasing the water use efficiency of the plant, likely through their effect on soil structure and the pore-size distribution.
Open area rainfall and throughfall measurements in the Western Tatra Mountains (altitude about 1500 m a.s.l.) made by tipping bucket gauges were used to estimate the usefulness of the short-time data in analysis of spruce interception. The 10-minute data from period 13 May-13 October 2009 did not reveal meaningful correlations between the open area rainfall and throughfall. Aggregated measurements representing individual rainfall events were more useful. They showed linear relationship between open area rainfall and throughfall for events with total rainfall depth in the open area exceeding 5 mm. Correlation between open area rainfall and throughfall for rainfall events with duration above 120 minutes was significantly better than for the shorter ones. Mean values of interception (percentage of open area rainfall which did not appear in throughfall) of individual rainfall events was high. When we excluded events for which throughfall was higher than the open area rainfall, mean interception for larger and longer rainfall events was 46% and 48%, respectively. For smaller (runoff depth below 5 mm) and shorter events (duration below 2 hours) the mean interception was 70% and 72%, respectively. However, the data revealed very high variability of interception. and Príspevok sa zaoberá hodnotením užitočnosti krátkodobých meraní zrážok na otvorenej ploche a v smrekovom lese pri určovaní intercepcie. Vychádza z merania zrážok preklápacími zrážkomermi v Západných Tatrách v nadmorskej výške okolo 1500 m n.m. Desaťminútové údaje merané v období 13.5.- 13.10.2009 neposkytli použiteľné korelácie medzi dažďom na otvorenej ploche a v lese. Lepšie výsledky boli získané pre sumárne úhrny zrážok pre jednotlivé dažde. Ak úhrn dažďa na voľnej ploche prekročil približne 5 mm, veľkosť podkorunových zrážok rástla lineárne s veľkosťou zrážok na voľnej ploche. Korelácia medzi zrážkami na voľnej ploche a v lese pre dažde s dĺžkou trvania nad 120 minút bola podstatne lepšia, ako pre kratšie dažde. Priemerná hodnota intercepcie (vyjadrenej ako percento zrážok na voľnej ploche, ktoré sa neobjavilo v lese) pre jednotlivé zrážkové udalosti bola vysoká. Po vylúčení udalostí, pre ktoré bol v lese nameraný vyšší úhrn zrážok ako na voľnej ploche, bola priemerná intercepcia pre väčšie dažďe 46 % a pre dlhšie dažde 48 %. Pre menšie (úhrn pod 5 mm) a kratšie (trvanie pod 2 hodiny) dažde bola priemerná intercepcia 70 % a 72%. Hodnoty intercepcie pre jednotlivé udalosti však mali veľkú variabilitu.
The paper summarises experience with runoff modelling in mountain catchment of the Jalovecky creek, Western Tatra Mountains, Slovakia, using TOPMODEL. The work was focused on runoff reproduction and estimation of areal extent of saturated areas, both with different time steps of input meteorological data (hourly or daily) and grid size of input digital elevation model (DEM). Simulations with the daily data from summer months 1988-1993 provided slightly overestimated runoff and saturated areas reached up to 5-19% of catchment area (for the DEM grid size of 10 m). Model parameters for each season were invariant. Hourly input data provided more heterogeneous results. Runoff reproduction was best for single long flood events and model parameters for different events varied. Saturated areas for the DEM grid size of 10 m varied between 1.1 and 10.8% of catchment area. The grid size did not influence runoff reproduction. The change of DEM resolution affected only the surface/subsurface flow ratio and, consequently areal extent of saturated areas. Modelled saturated areas cumulated along the main stream network. High modelled contribution of subsurface runoff to total catchment runoff was in accordance with the results of hydrograph separations. Field measurements of soil moisture in the upper soil layer indicated important role of vegetation (forest) which was not considered by the model. and V príspevku sme zhrnuli skúsenosti s matematickým zrážkovoodtokovým modelom TOPMODEL pri modelovaní odtoku v horskom povodí Jaloveckého potoka v Západných Tatrách. Zaujímala nás najmä schopnosť modelu reprodukovať odtok z horského povodia a predpovedať plošný rozsah nasýtených oblastí pri rôznom časovom kroku vstupných údajov a rôznej veľkosti štvorca siete digitálneho modelu reliéfu. Pri simulácii odtoku s dennými vstupnými údajmi za letné mesiace rokov 1988-1993 bol modelovaný odtok mierne nadhodnotený a nasýtené oblasti pri štvorci siete 10 m predstavovali maximálne 5-19 % plochy povodia. Parametre modelu v jednotlivých rokoch nebolo potrebné meniť. Pri práci s hodinovými údajmi boli výsledky rôznorodejšie. Lepšia zhoda meraného a simulovaného odtoku bola dosiahnutá pri dlhšie trvajúcich vlnách a parametre modelu boli pre rôzne vlny rôzne. Pre rôzne vlny kolísal maximálny rozsah nasýtených oblastí pri štvorci siete 10 m od 1,1 do 10,8 % plochy povodia. Veľkosť štvorca siete nemala vplyv na simuláciu celkového odtoku z povodia a prejavila sa len na pomere povrchového a podpovrchového odtoku a následne na rozsahu nasýtených oblasti. Modelované nasýtené oblasti sa vyskytujú v blízkosti riečnej siete. Vyhodnotenie meraní vlhkostí pôdy v povodí poukazuje na značný vplyv vegetácie. Keďže v predkladanej práci bola použitá verzia modelu, ktorá neobsahuje simulácie procesov v nadzemných častiach prostredia, bolo simulované rozdelenie nasýtených oblastí v lesnatých častiach povodia modelom odlišné od rozdelenia zisteného priamym pozorovaním v povodí. Vysoký podiel modelovaného podpovrchového odtoku v celkovom odtoku bol potvrdený aj separáciou odtoku pomocou prírodných izotopov.
In this study, the simulation results of four vertical flow wetland systems using the HYDRUS Wetland Module are presented. The four wetland systems comprise three single-stage pilot scale systems and one full-scale two-stage system. The main difference between these systems is the filter media used, referred to as fine media, i.e., sand with a grain size distribution 0.063–4 mm, or coarse media, i.e., sand with grain size distributions between 1–4 mm, respectively. The water-flow simulation of each system is carried out using the single porosity van Genuchten-Mualem model. A good match between measured and simulated volumetric effluent flow rates could be achieved for all wetland systems. For reactive transport simulations, the CW2D biokinetic model was applied. First, simulations were run using the standard CW2D parameter set. For some systems, adjustments of the parameter set were needed in order to avoid unlimited bacteria growth. To better fit measured COD, NH4-N, and NO3-N effluent concentrations, adjustments of few parameters of the standard parameter set were required. The results show that for the VF wetlands with fine sand, no adjustments of the CW2D standard parameter set were needed, while for systems with coarser filter media as the main layer, the standard parameter set had to be adjusted to match simulated and measured effluent concentrations.
Extensive lowland floodplains cover substantial parts of the glacially formed landscape of Northern Germany. Stream power is recognized as a force of formation and development of the river morphology and an interaction system between channel and floodplain. In order to understand the effects of the river power and flood power, HEC-RAS models were set up for ten river sections in the Upper Stör catchment, based on a 1 m digital elevation model and field data, sampled during a moderate water level period (September, 2011), flood season (January, 2012) and dry season (April, 2012). The models were proven to be highly efficient and accurate through the seasonal roughness modification. The coefficients of determination (R2 ) of the calibrated models were 0.90, 0.90, 0.93 and 0.95 respectively. Combined with the continuous and long-term data support from SWAT model, the stream power both in-channel and on the floodplain was analysed. Results show that the 10-year-averaged discharge and unit stream power were around 1/3 of bankfull discharge and unit power, and the 10-year-peak discharge and unit stream power were nearly 1.6 times the bankfull conditions. Unit stream power was proportional to the increase of stream discharge, while the increase rate of unit in-channel stream power was 3 times higher than that of unit stream power on the floodplain. Finally, the distribution of the hydraulic parameters under 10-years-peak discharge conditions was shown, indicating that only 1-10% of flow stream was generated by floodplain flow, but 40-75% volume of water was located on the floodplain. The variation of the increasing rate of the stream power was dominated by the local roughness height, while the stream power distributed on the floodplain mainly depended on the local slope of the sub-catchment.
The potential impact of climate change on the mean monthly runoff in the upper Hron River basin, which was chosen as a representative mountainous region in Central Slovakia, was evaluated. A conceptual hydrological balance model calibrated with data from the period 1971-2000 was used for modelling changes in runoff with monthly time steps. Changes in climate variables in the future were expressed by two different climate change scenarios developed within the framework of the CECILIA (Central and Eastern Europe Climate Change Impact and Vulnerability Assessment) project. The climate change scenarios were constructed using the pattern scaling method from the outputs of transient simulations made by 2 GCMs - ECHAM4/OPYC3 and HadCM2 (Dubrovský et al., 2005). The runoff change scenarios for the selected basin in the future time horizons of 2025, 2050 and 2100 show changes in the runoff distribution within a year. Changes in the seasonal runoff distribution were compared with previous results (Danihlík et al., 2004), which were achieved with climate change scenarios developed from the outputs of the CCCM97 and GISS98 global circulation models. and Článok sa zaoberá skúmaním vplyvu možnej zmeny klímy na sezónne rozdelenie odtoku na povodí horného Hrona. Na modelovanie priemerných mesačných prietokov bol použitý koncepčný model hydrologickej bilancie v mesačnom kroku, s parametrami kalibrovanými na referenčné obdobie 1971-2000. Zmeny klimatických charakteristík boli vyjadrené podľa 2 klimatických scenárov, spracovaných pre povodie horného Hrona v rámci projektu 6 RP CECILIA (Central and Eastern Europe Climate Change Impact and Vulnerability Assessment). Klimatické scenáre boli spracované na základe výstupov tranzietných simulácií 2 globálnych cirkulačných modelov ECHAM4/OPYC3 a HadCM2 (Dubrovský et al., 2005) pre budúce časové horizonty 2025, 2050 a 2100. Podľa hydrologických scenárov priemerných mesačných prietokov možno v budúcnosti na povodí horného Hrona predpokladať zmeny sezónneho rozdelenia odtoku. Predpokladané zmeny sezónneho rozdelenia odtoku sú konzistentné s výsledkami dosiahnutými v predchádzajúcich prácach (Danihlík et al., 2004), v ktorých boli hydrologické scenáre odtoku na povodí horného Hrona spracované na základe klimatických scenárov, založených na výstupoch globálnych cirkulačných modelov CCCM97 a GISS98.