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This study aimed to examine the vertical stratification of the soil seed bank in wet grasslands, with a special emphasis on seeds in deeper soil layers that are generally not considered in seed bank studies. We studied the soil seed bank at four depths: 0–10 cm, 10–30 cm, 30–50 cm, 50–70 cm in five study sites in Central Hungary. The seedling emergence method was used to detect viable seeds. The relationship between the vertical stratification of the seed bank and species traits was studied using generalized linear mixed models. We also sampled the aboveground vegetation and applied non-metric multidimensional scaling to evaluate the species composition of the seed bank and vegetation. The species richness and the seed density of different layers were significantly different; both decreasing with increasing depth. Although most viable seeds were found in 0–10 cm depth (22,632 seeds/m2), an unexpected large number of seeds germinated also from the deepest soil layer (50–70 cm; 4170 seeds/m2). Species without morphological specializations for spatial seed dispersal (i.e., Allium dispersal type), lower water requirements, and heavier seeds occurred in great abundance in the deeper soil layers. The dominance of species without specialized spatial dispersal suggests that they invest more in temporal dispersal by the soil seed bank. Forbs and perennial species dominated both the seed bank and the aboveground vegetation; however, the dominant species in the seed bank did not correspond to the dominant species in the aboveground vegetation. Our results suggest that the seed bank of wet grasslands does not contain the full habitat-specific species pool despite its high seed density and species richness. The restoration of the studied wet grasslands cannot rely solely on the local seed banks.

In electric vehicles battery life can be prolonged by using hybrid energy storage systems (HESS ), which combine high energy density batteries with supercapacitors, characterized by high power density. This paper deals with the control of electronic power converters from an active parallel HESS. The load of the HESS is the electrical motor drive of an electric vehicle. The interfaces between the DC-link and the power sources are four-phase bidirectional DC-DC converters driven in current control mode, based on the current references supplied by an active parallel HESS power distribution algorithm. We present a rule-based fuzzy energy management algorithm for a HESS powered electric vehicle and its simulation in MATLAB/Simulink®environment using the Quasi-Static Simulation (QSS ) and Fuzzy Logic toolboxes. Also, simulation results in driving and regenerative braking operation modes of the electric vehicle are presented.

We have tested the stability of interrater reliability of psychiatric symptoms over a quarter of century using 2 rating scales. Interrater reliabilities of items of 2 psychiatric rating scales employed by 2 consecutive follow-ups were compared. Interrater reliabilites proved to be by and large stable. Interrater reliability depends on the standard deviation of the items scores. In addition to the traditional approach, a new statistical method for unifying the assessments from multiple raters is also presented. Using this method, we demonstrated that probabilities of correct ratings are higher in the absence of manifest symptoms, or in the presence of symptoms, as compared with cases characterized by middle scores. To interpret the relationships revealed in the setting of the experiment, we introduce for its theoretical designation the term “validity of reliability.” It is recommended for evaluation of results of rating scales in the context of psychiatric nosology.

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