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The effect of microelement loads was investigated on the mobile (1 M NH 4 NO 3 soluble), mobilizable (NH 4 -acetate + EDTA soluble) and pseudo total (cc. HNO 3 + H 2 O 2 ) element concentrations of a calcareous chernozem soil in a long-term field experiment. Salts of 13 microelements were applied on four levels: 0, 90, 270 and 810 kg/ha in the spring of 1991 prior to sowing maize. The relations between the mobile, mobilizable and pseudo total fractions of a heavy metal contaminated soil were defined and quantified. According to this, Ba, Mo, Sr and Se have the greatest mobility, while Cu, Ni and Zn showed strong fixation on the examined soil. The maximum quantities of elements incorporated in the whole above-ground yield of maize were as follows (in g/ha): Al 1548, Zn 543, Mo 352, Ba 269, Cd 201, Se 153, Sr 116, Cu 64, Pb 22, Ni 15, Hg 8, Cr 4 and As <1. Transfer coefficients calculated as a quotient of different soil element fractions and maize grain and stem element contents were compared. In the case of grain the greatest accumulation was found in relation to the Ni, Cu and Se contents of the mobile fraction. The coefficient values were 3, 5 and 7, respectively. Coefficients for stem may exceed those obtained for grain. The accumulation decreases as a function of loads. The coefficients for NH 4 NO 3 extractions show the greatest standard deviation, thus this quotient indicates the heavy metal and toxic element accumulation in plants with the greatest sensitiveness.

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Bending, twitching and quivering are different types of tentacle movements observed during olfactory orientation of the snail. Three recently discovered special muscles, spanning along the length of superior tentacles from the tip to the base, seem to be responsible for the execution of these movements. In this study we have investigated the ultrastructure, contractile properties and protein composition of these muscles. Our ultrastructural studies show that smooth muscle fibers are loosely embedded in a collagen matrix and they are coupled with long sarcolemma protrusions. The muscle fibers apparently lack organized SR and transverse tubular system. Instead subsarcolemmal vesicles and mitochondria have been shown to be possible Ca2+ pools for contraction. It was shown that external Ca2+ is required for contraction elicited by high (40 mM) K+ or 10−4 M ACh. Caffeine (5 mM) induced contraction in Ca2+-free solution suggesting the presence of a substantial intracellular Ca2+ pool. High-resolution electrophoretic analysis of columellar and tentacular muscles did not reveal differences in major contractile proteins, such as actin, myosin and paramyosin. Differences were observed however in several bands representing presumably regulatory enzymes. It is concluded that, the ultrastructural, biochemical and contractile properties of the string muscles support their special physiological function.

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Summary  

The determination of transuranic (TRU) content in nuclear wastes, reactor materials, process solutions, and various other matrices is required in support of material assessment, environmental restoration, and waste processing activities. We have found that direct measurement of TRU is possible using surface passivated ion implanted planar silicon diode detectors. The performance and durability of modern silicon diodes enables direct detection of alpha-particles, with retention of some spectral information, through small air gaps or under direct contact with liquid or solid samples. We will present results on the performance of silicon diode detectors for the determination of TRU in liquids.

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An evolutionary approach to social cognition yields novel hypotheses about the perception of people belonging to specific kinds of social categories. These implications are illustrated by empirical results linking the perceived threat of physical injury to stereotypical impressions of outgroups. We review a set of studies revealing several ways in which threat-connoting cues influence perceptions of ethnic outgroups and the individuals who belong to those outgroups. We also present new results that suggest additional implications of evolved danger-avoidance mechanisms on interpersonal communication and the persistence of cultural-level stereotypes about ethnic outgroups. The conceptual utility of an evolutionary approach is further illustrated by a parallel line of research linking the threat of disease to additional kinds of social perceptions and behaviors. Evolved danger-avoidance mechanisms appear to contribute in diverse ways to individual-level cognitive processes, as well as to culturally-shared collective beliefs.

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Acta Physiologica Hungarica
Authors: Márk Váczi, É. Tékus, M. Kaj, T. Kőszegi, M. Ambrus, J. Tollár, T. Atlasz, K. Szabadfi, and I. Karsai

We hypothesized that stair-jump exercise would induce less muscle damage and greater acute metabolic responses than level-jumps.

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Background and aims

Internet gaming disorder (IGD) imposes a potential public health threat worldwide. Gaming motives are potentially salient factors of IGD, but research on Chinese gaming motives is scarce. This study empirically evaluated the psychometric properties of the Chinese version of the Motives for Online Gaming Questionnaire (C-MOGQ), the first inventory that measures seven different gaming motives applicable to all type of online games. We also investigated the associations between various gaming motives and IGD symptoms among Chinese gamers.

Methods

Three hundred and eighty-three Chinese adult online gamers (Mean age = 23.7 years) voluntarily completed our online, anonymous survey in December 2015.

Results

The confirmatory factor analysis results supported a bi-factor model with a general factor subsuming all C-MOGQ items (General Motivation) and seven uncorrelated domain-specific factors (Escape, Coping, Fantasy, Skill Development, Recreation, Competition, and Social). High internal consistencies of the overall scale and subscales were observed. The criterion-related validity of this Chinese version was also supported by the positive correlations of C-MOGQ scale scores with psychological need satisfaction and time spent gaming. Furthermore, we found that high General Motivation (coupled with high Escape motive and low Skill Development motive) was associated with more IGD symptoms reported by our Chinese participants.

Discussion and conclusions

Our findings demonstrated the utility of C-MOGQ in measuring gaming motives of Chinese online gamers, and we recommend the consideration of both its total score and subscale scores in future studies.

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Acta Physiologica Hungarica
Authors: K. Csanaky, D. Reglődi, E. Bánki, I. Tarcai, L. Márk, Zs Helyes, T. Ertl, J. Gyarmati, K. Horváth, L. Sántik, and Andrea Tamás

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with special importance in reproductive and developmental processes. PACAP is found in two bioactive forms: PACAP27 and PACAP38. Recently, we have described that PACAP38 is present in high levels in the milk of human and ruminant animals. Breastfeeding is of utmost importance in proper nutrition of the newborn, but artificial nursing with infant formulas is necessary when breastfeeding is not available. Composition of the breast milk varies during the whole period of nursing and it shows differences at the beginning (foremilk) and the end of an actual suckling (hindmilk). The aim of this study was to investigate PACAP38-like immunoreactivity (PACAP38-LI) in different milk and infant formula samples by radioimmunoassay and to prove the presence of PACAP38 in the infant formula by mass spectrometry. We found similar PACAP38-LI in human mature foremilk and hindmilk samples, in the fresh and pasteurized cow milk and also in formulas. However, we found significantly higher PACAP38-LI in the hypoantigenic formula undergoing extensive hydrolysis compared to the non-hypoantigenic ones. Our results suggest that PACAP38 is relatively stable in the milk and it can withstand the manufacturing processes.

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