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Periphyton spamles from the reed-belt and phytoplankton samples were taken in November 1996 and in January, April, July 1997 at the upper part of  the Soroksár-Danube (the second largest side arm of river Danube in Hungary) at Taksony, and in July, November 1998, January, April 1999 at the middle part of the side arm at Ráckeve. The aim of this study was to investigate the seasonal and vertical distribution of periphyton growing on old and green reed stemps at both parts of the side arm, focussed on taxonomic composition, abundance and chlorophyll a content.             Based on the chloropyll a content of the phytoplankton the upper part of the side arm at Taksony was oligotrophic in November an July (in July caused by a flood), mesotrophic in Januray and eutrophic in April. The middle part of the Soroksár-Danube was eutrophic in April and July, oligotrophic in November and January at Ráckeve             The values of abundance and chlorophyll a of periphyton were the highest at the middle part of Soroksár-Danube, while that of phytoplankton was the highest at the upper part.             A few diamonts showed the same distribution along the reed stems. Relative abudance of Amphora libyca, Cocconeis placentula and Eunotia arcus increased close to the bottom, while that of Fomphonema minutum, G. paravulum, Navicula capitatoradiata and Nitzschia dissipata decreased.

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Benthic diatom investigations of some Hungarian streams have been carried out in order to find reference sites in assistance to the ecological quality analysis of the different river types according to the Hungarian river typology. On the basis of the coevaluation of biological and chemical parameters, among the investigated streams, some part of Kemence stream seems to be the appropriate reference site for the classification of the highland, siliceous rivers of Hungary. However, further invastigations are needed for the selection of reference sites for the other types of Hungarian river typology. This is the most difficult in the case of lowland rivers, which are exposed to more severe anthropogenic impacts. Important is the question which biological parameters should be investigated and considered when assessing the ecological condition of our waters. In the United States, e.g. the assessment of the relative abundance of Achnanthidium minutissimum is quite widespread (Stevenson and Bahls 1999), the extent of which indicates the level of disturbance. The use of this method is hampered, on one hand, by the fact that A. minutissimum is an early coloniser species which means that if we do not take samples from mature periphyton, we might find it dominant simply because of that, and, on the other hand, that distinguishing between the species varieties is not always unambiguous under light microscope because of its small size, and these can have different ecological needs. It is also recommended to calculate species richness, diversity and evenness (Stevenson and Bahls 1999), but based on our investigations these parameters are not in correlation with water quality. Investigation of other diatom features such as tolerance and sensitivity, some autecological parameters (as it was applied and recommended by Fore and Grafe 2002 for investigating the reaction of diatom associations to anthropogenic disturbances) might also be useful in completing the water quality analysis of rivers, however, these methods need further investigations. Some of the indices (EPI-D, IPS, IBD) calculated with the software Omnidia are suitable for the classification of our rivers, but the investigation of more rivers, flowing through different types of stone are necessary to choose the appropriate indices. The reason for this is that the different indices work with a different register of species and obviously those indices will prove to be suitable the species register of which shows the highest similarity to the diatom associations of the certain water type.

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Plankton samples collected from a yellow watered bog pool of the mesotrophic “Călăţele Pădurii” peat bog (Romanian Western Mountains, Transylvania), exhibited an outstandingly rich Mallomonas population. The observations carried out by light and scanning electron microscopy revealed that the population belongs to Mallomonas intermedia Kisselev. Based on the presence of lance head bristles, distributed all over the cell armour (except few anterior collar, unilaterally serrated ones), it became evident that the population belong to the nominate variety (var. intermedia). Mallomonas intermedia var. saliceaensis formerly described from Transylvania differs by the type variety by the presence of exclusively serrated bristles. The present finding proved that Mallomonas intermedia could not be properly identified at infraspecific level solely based on the ultra structure of scales, without knowing the structure of bristles, too.

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DSC studies on the polymorphism and pseudopolymorphism of pharmaceutical substances

A complex system for studying physico-chemical behaviour of binary mixtures

Authors: K. Marthi, M. Ács, G. Pokol, K. Tomor and K. Eröss-Kiss

A complex system including thermoanalytical methods, infrared spectroscopy and X-ray powder diffraction for studying physico-chemical behaviour of binary mixtures is described. This system has been tested by investigating binary mixtures of amphetamine hydrochloride salts.

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The suitability of benthic diatoms in the biological monitoring program of the water quality of Lake Velence was tested. Diatom indices were calculated with the aid of the software Omnidia based on reed periphyton samples collected between 1988 and 1990, and 1999 to 2004. We have pointed out which indices are appropriate for indicating the water quality changes of Lake Velence. The correlation between the indices IBD, IPS, IDG, and the total nitrogen, total phosphorus content of the water and chlorophyll-a content of the periphyton was calculated. Significant negative correlation was found between the indices and the total phosphorus content of the water. Moreover, we concluded that the chlorophyll-a content of the periphyton related to surface area can also provide information about the water quality. Based on these results the index IBD seems to be the most suitable for the water quality analysis of Lake Velence. Recommendations are provided here concerning the ecological status classification of Lake Velence based on epiphytic diatoms; unaccounted questions and future assignments are also outlined in connection with this.

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Authors: F. Békés, K. Ács, Gy. Gell, Cs. Lantos, A-M. Kovács, Zs. Birinyi and J. Pauk

Consumption of “gluten-containing” diet causes disease for a significant minority of people who consume foods derived from wheat, rye, barley, and possibly oat. The fact is, however, that in several types of diseases related to the consumption of “gluten-containing” cereals, the trigger compounds are not components of gluten. The current view of medical experts is that, excluding people suffering from celiac disease, the majority of individuals who are feeling better on the “wheat-free” or “gluten-free” diet could select a food containing much healthier, low level of fermentable oligosaccharides (often called as FODMAP). To satisfy the specific health related demands of certain consumer groups, the challenge is in front of cereal breeding to develop new, “healthier” germplasms, suitable to produce such products by the food industry. This report aims to give an overview of some aspects of recent developments in this booming area, (i) summarizing the up-to-date knowledge on cereals-related health disorders; (ii) reporting on the status of developing celiac-safe cereals, and finally (iii) highlighting the potential of developing “healthier” spelt-based cereal products through the progress in an ongoing spelt breeding program.

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Authors: István Nász, Éva Ádám, ANNA Lengyel, K. Ács, Zs. Kasza, M. Vastag and Cs. Vágvölgyi
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Authors: Q. Riaz, K. Ács, F. Békés, R.F. Eastwood, A. Farahnaky, M. Majzoobi and C.L. Blanchard

Grain fructans play an important role in the physiology of wheat plants and also impact on the health of consumers of wheat-based products. Given the potential economic importance of fructan levels, if genetic variability could be identified for this trait, it may be a potentially useful breeding target for developing climate-resilient and nutritionally enhanced wheat varieties. The aim of the current study was to screen 78 genetically diverse Australian wheat varieties released between 1860 and 2015 to determine if historic breeding targets have resulted in changes in fructan levels and to identify potential breeding parents for the development of varieties with specific fructan levels. The impact of seasonal conditions on grain fructan levels were also investigated. Analysis of the varieties in this study indicated that historic breeding targets have not impacted on grain fructan levels. Fructan content in flours varied between 1.01 to 2.27%, showing some variation among the varieties. However, a significant variation in fructan levels was observed between different harvest years (mean values for 2015 and 2016 samples were 1.38 and 1.74%, respectively). While large variations in fructan contents of different varieties were not found, there were some varieties with consistently higher or lower fructan contents which could be used to breed varieties with specific fructan levels.

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Authors: A. Lugasi, K. Neszlényi, J. Hóvári, K. V. Lebovics, A. Hermán, T. Ács, J. Gundel and I. Bodó

Fat content and fatty acid composition were investigated in Musculus gluteus medius of pigs from two different breeds: traditional Hungarian Mangalica and a crossbreed of Hungarian Large White and Dutch Landrace. Animals of both varieties were divided into two groups and were kept individually on control or experimental mixtures of feeds. Experimental feed contained significantly higher amount of linoleic and linolenic acid than the control one. Significantly higher fat content was detected in meat of Mangalica pigs kept on both feed mixtures than in those of crossbred. The proportion of saturated fatty acids was nearly the same in the meat of both genotypes. More monounsaturated fatty acids were detected in Mangalica meat than in crossbred ones expressed in percent of total fatty acids and absolute amount, as well. As a result of experimental diet, percentage and absolute amount of oleic acid decreased significantly in both genotypes. Less polyunsaturated fatty acids expressed as percent of total acids were observed in the muscle of Mangalica than in those of crossbred ones. Absolute amount and the proportion of total polyunsaturated fatty acids (especially linoleic and linolenic acids) increased significantly as a result experimental diets. The ratio of n-6 and n-3 fatty acids changed beneficially in both genotypes consuming a diet containing 20% full-fat soy from 13.6:1 to 10.0:1 in Mangalica and from 15.4:1 to 10.3:1 in crossbred genotype. According to present results, it has became clear that the fatty acid composition of the meat of the traditional Hungarian Mangalica can be successfully modified by the diet, and this manipulation can make the meat healthier in spite of its high fat content.

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Authors: A Muller, N Gal, J Betlehem, N Fuller, P Acs, GL Kovacs, K Fusz, R Jozsa and A Olah

We examined the effects of different shift work schedules and chronic mild stress (CMS) on mood using animal model. The most common international shift work schedules in nursing were applied by three groups of Wistar-rats and a control group with normal light—dark cycle. One subgroup from each group was subjected to CMS. Levels of anxiety and emotional life were evaluated in light—dark box. Differences between the groups according to independent and dependent variables were examined with one- and two-way analysis of variance, with a significance level defined at p < 0.05. Interaction of lighting regimen and CMS was proved to be significant according to time spent in the light compartment and the average number of changes between the light and dark compartments. Results of our examination confirm that the changes of lighting conditions evocate anxiety more prominently than CMS. No significant differences were found between the results of the low rotating group and the control group, supposing that this schedule is the least harmful to health. Our results on the association between the use of lighting regimens and the level of CMS provide evidence that the fast rotating shift work schedule puts the heaviest load on the organism of animals.

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