A modified exponential model was used to describe light-response curves of Nicotiana tabacum L. The accuracies of an exponential model, a nonrectangular hyperbola model, a rectangular hyperbola model, a modified rectangular hyperbola model and the modified exponential model were evaluated by Mean square error (MSE) and Mean absolute error (MAE). The tests MSE and MAE of the modified exponential model were the lowest among the five models. The light saturation point (LSP) obtained by the exponential model, the nonrectangular hyperbola model and the rectangular hyperbola model were much lower than the measured values, and the maximum net photosynthetic rates (Pmax) calculated from these models, were greater than the measured values. Pmax at LSP of 1,077 μmol m-2 s-1 calculated by the modified exponential model was 12.34 μmol(CO2) m-2 s-1, which was more accurate than the values obtained from the modified rectangular hyperbola model. The results show that the modified exponential model is superior to other models for describing light-response curves. and Z. Y. Chen ... [et al.].
In this paper a model for the recovery of human and economic activities in a region, which underwent a serious disaster, is proposed. The model treats the case that the disaster region has an industrial collaboration with a non-disaster region in the production system and, especially, depends upon each other in technological development. The economic growth model is based on the classical theory of R. M. Solow (1956), and the full model is described as a nonlinear system of ordinary differential equations.
In this paper, we present a novel quantitative description of intracellular and t-tubular Ca2+ dynamics in a model of rat cardiac ventricular myocyte. In order to simulate recently published data, the model incorporates t-tubular and peripheral dyads and intracellular subspaces, segmentation of the t-tubular luminal volume, reformulation of the inactivation properties of t-tubular land peripheral L-type calcium current (ICa) and a description of exogenous Ca2q+ buffer function in the intracellular space. The model is used to explore activity-induced changes of ion concentration in the intracellular and t-tubular spaces and their role in excitation - contraction coupling in ventricular myocytes. and Obsahuje Appendix se seznamy literatury, užitých zkratek a symbolů
In this paper we show that the measure generated by the indefinite Henstock-Kurzweil integral is $F_{\sigma \delta }$ regular. As a result, we give a shorter proof of the measure-theoretic characterization of the Henstock-Kurzweil integral.
The general author‘s mesomechanical model with tensorial internal variables is applied to creep of steel 0,5Cr0,5Mo0,3V under different loading levels. It is shown that the creep process can be described by the mesomechanical model in its whole course up to rupture. However, the model parameters can be influenced at the very beginning by the application of the applied load if it is high enough to cause changes in the internal structure. This problem is specific for creep at high temperatures and significant differences in the loading levels (contrary to the small-strain plasticity studied usually at low temperatures, where the model parameters can be considered the same for different loadings). and Obsahuje seznam literatury
Steroid profiling helps various pathologies to be rapidly
diagnosed. Results from analyses investigating steroidogenic
pathways may be used as a tool for uncovering pathology
causations and proposals of new therapeutic approaches. The
purpose of this study was to address still underutilized application
of the advanced GC-MS/MS platform for the multicomponent
quantification of endogenous steroids. We developed and
validated a GC-MS/MS method for the quantification of
58 unconjugated steroids and 42 polar conjugates of steroids
(after hydrolysis) in human blood. The present method was
validated not only for blood of men and non-pregnant women
but also for blood of pregnant women and for mixed umbilical
cord blood. The spectrum of analytes includes common
hormones operating via nuclear receptors as well as other
bioactive substances like immunomodulatory and neuroactive
steroids. Our present results are comparable with those from our
previously published GC-MS method as well as the results of
others. The present method was extended for corticoids and
17α-hydroxylated 5α/β-reduced pregnanes, which are useful for
the investigation of alternative “backdoor” pathway. When
comparing the analytical characteristics of the present and
previous method, the first exhibit by far higher selectivity, and
generally higher sensitivity and better precision particularly for
17α-hydroxysteroids.
The paper introduces the test of aggregation as a simple, inexpensive method of evaluating suspension quality during drinking water treatment, suitable for use in both laboratory and operation conditions. The procedure and derivation of the aggregation test is described. The method is used for a demonstration of the influence of mean velocity gradient and mixing time on floc properties formed during the aggregation in a Couette reactor. It was proved that with increasing velocity gradient, the size of the aggregates present in the suspension decreases, and the suspension is substantially more homogeneous than with use of lower gradients. Further, it was confirmed that the size of aggregates reaches the steady state after a specific mixing time, which becomes shorter with increasing value of velocity gradient. and Příspěvek představuje test agregace jako jednoduchou a levnou metodu stanovení kvality suspenze při úpravě vody vhodnou pro použití v laboratorních i provozních podmínkách. Je popsán metodický postup i odvození testu agregace. Metoda je použita pro hodnocení vlivu středního gradientu rychlosti a doby míchání na vlastnosti vytvářených agregátů (vloček) při agregaci v Couettově reaktoru. Bylo prokázáno, že se vzrůstajícím gradientem se snižuje velikost agregátů přítomných v suspenzi a suspenze je značně více homogenní než při použití nízkých gradientů rychlosti. Dále bylo potvrzeno, že velikost agregátů dosahuje po určité době míchání stabilní hodnoty. Čas pro dosažení tohoto ustáleného stavu se zkracuje s rostoucí hodnotou použitého gradientu.
This paper describes an invented method for direct measurement of coalbed methane content in situ. In contrast to known procedures, this method does not need to place a rock or drilling cuts into an airtight canister, and does not involve sealing of the hole. Moreover, the new method is monitoring methane content in situ continuously and synchronously during drilling the hole not losing any portion of the gas. These positive features are a sequel of new approach based on injection of known portion of neutral gas into the hole. Methane content was determined from concentration of the mixture ‘methane-neutral gas´ at the hole´s mouth. New method is applicable for commercial recovery application of coalbed methane and forecast of dangerous gas and coal bursts. FLAC3D computer simulation helped to investigate dynamics of methane outflow from the hole to account for the effect of drilling speed on the rate of gas emanation.
A simple method of a bicolor (multicolor), fast-Fourier, PAM chlorophyll fluorometry has been developed to obtain fluorescence induction curves. Quantum yields of PSII photochemistry were determined with blue and red simultaneously applied pulsed measuring lights for three subsequent 20-min periods of dark-, light-adaptation under actinic light and dark recovery. Measuring lights were cross-combined with blue and red actinic lights and saturation pulses. Coefficients of chromatic divergence were calculated as a ratio of the quantum yields obtained by red measuring light to that obtained by blue measuring light. Adaptation of Ficus benjamina and Hordeum vulgare leaves under blue (but not red) actinic light resulted in the sufficient increase of chromatic divergence. In addition, fraction of active, non(photo)inhibited, PSII centers was shown to be dependent on the color of measuring light. Thus, color of the light sources should be considered when reporting results of parameters evaluated from fluorescence induction curves., V. Lysenko, D. Lazár, T. Varduny., and Obsahuje bibliografii
Text sentiment analysis plays an important role in social network information mining. It is also the theoretical foundation and basis of personalized recommendation, circle of interest classification and public opinion analysis. In view of the existing algorithms for feature extraction and weight calculation, we find that they fail to fully take into account the in fluence of sentiment words. Therefore, this paper proposed a fine-grained short text sentiment analysis method based on machine learning. To improve the calculation method of feature selection and weighting and proposed a more suitable sentiment analysis algorithm for features extraction named N-CHI and weight calculation named W-TF-IDF, increasing the proportion and weight of sentiment words in the feature words Through experimental analysis and comparison, the classification accuracy of this method is obviously improved compared with other methods.