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Utilization of algae includes both macroalgae for human consumption dating back to thousands of years, as well as the application of microalgae in health promoting dietary supplements. The autotrophic growth of microalgae is slow, but can be accelerated by optimizing their cultivation conditions. Efficiency optimizations for time and economy should be performed in many parallel experiments. A new high-throughput microalgae cultivation method is presented here, applying 24-low-well microplate with varying illumination, in which the cell growth is followed via evaluation of scanned images. A strain of the genus Nannochloropsis and two Chlorella vulgaris species have been chosen as well described and frequently applied model organisms in order to test the recently developed cultivation system. In these scaled down experiments, the custom design lighting panel was tested by studying the effect of the colour of illumination on cell growth kinetics. RGB LEDs (i.e. light emitting diodes, red: 622 nm, green: 528 nm, and blue: 467 nm) were used individually or together providing red, green, blue, and white colours. While the effect of light’s colour on algae growth was evaluated, also the new system was proven to be suitable for comparing maximal growth rates for different microalgae strains. While the tested two Chlorella isolates reached 1.2–1.4 g l–1 concentrations, the Nannochloropsis strain reached 1.4 g l–1 final cell dry weight, and specific growth rates were observed between 0.58–0.62 day–1.

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A new preconditioned conjugate gradient (PCG)-based domain decomposition method is given for the solution of linear equations arising in the finite element method applied to the elliptic Neumann problem. The novelty of the proposed method is in the recommended preconditioner which is constructed by using cyclic matrix. The resulting preconditioned algorithms are well suited to parallel computation.

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In Hungary rice ( Oryza sativa L.) is cultivated under flooded conditions. Direct seeding into the soil is applied usually. The optimal sowing date is a key factor necessary to the success of this annual crop because of the relatively short growing season. The main objective of this research was to: (1) analyse duration of period from sowing to emergence at different temperature values, (2) determine base temperature of this phenophase and (3) establish a thermal time model for rice emergence. To do this, growth chamber experiments with 5 Hungarian cultivars were conducted to determine the time to median emergence (E 50 ) at constant temperature of 14 to 34 °C in 2 °C steps. The sowing depth was 2 cm, and moisture was not a limiting factor. It was found that the critical thermal zone, which is of highest practical importance, is between 14 and 16 °C. At these values the E 50 is 23.9 and 13.4 days, respectively, showing a border between unfavourable and acceptable conditions. In the temperature interval between 26 and 34 °C the time needed for emergence was only 3.3 to 4.4 days. Variety differences were also detected. Base temperature was found between 9.8 and 10.9 °C. The thermal time requirements of 4 cultivars varied between 69 and 73 °C day. Data of field experiment with 9 sowing dates and a pot experiment with 3 sowings confirmed that our thermal time model can successfully simulate the emergence of rice.

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Building life cycle assessment is getting more and more attention within the topic of environmental impact caused by the built environment. Although more and more research focus on the embodied impact of buildings, the investigation of the operational energy use still needs attention. The majority of the building stock still does not comply with the nearly zero energy requirements. Also, in case of retrofitting, when most of the embodied impact is already spent on the existing structures (and so immutable), the importance of the operational energy rises. There are several methods to calculate the energy performance of buildings covering the range from simplified seasonal methods to detailed hourly energy simulations. Not only the accuracy of the calculations, but the computational time can be significantly different within the methods. The latter is especially important in case of optimization, when there is limited time to perform one calculation. Our research shows that the use of different calculation techniques can lead to different optima for environmental impacts in case of retrofitting. In this paper we compare these calculation methods with focus on computational time, accuracy and applicability to environmental optimization of buildings. We present the results in a case study of the retrofitting of a middle-sized apartment house in Hungary.

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Plant sucking aphids cause both quantitative and qualitative yield losses in cereals; moreover aphid-transmitted viruses are responsible for other quantitative and qualitative damages, thus direct or indirect effects of aphid infection are in focus of interest. Bread-making quality of wheat flour is determined primarily by the protein content and composition, the gluten proteins (glutenins, gliadins) being the prime factors. Allelic composition of the gliadin- and glutenin loci as well as the absolute amount and/or the relative ratio of gliadins to glutenins are very important in dough making and in determining baking quality. Wheat plants were caged at the beginning of stem elongation. Cages were treated with 0.1% methyl parathion. One week later, the caged plants were artificially infected with 5 alata individuals of Metopolophium dirhodum, Diuraphis noxia, Sitobion avenae and Rhopalosiphum padi. Flour from grains originating from plants infected artificially with cereal aphids were analyzed for glutenin and gliadin and total protein content, using Size Exclusion HPLC. It was found that aphid infection had significant effect on the glutenin and gliadin content, the total protein content and the gliadin/glutenin ratio. Both the glutenin and gliadin content was significantly higher in the seeds harvested from aphid infected plants. However, the gliadin/glutenin ratio was significantly lower in wheat flour prepared from aphid infected plants than in those from uninfected control. The most significant decrease in gliadin/glutenin ratio was caused by M. dirhodum, D. noxia, S. avenae infection followed by R. padi at high-abundance and low-abundance, respectively. As the gliadin/glutenin ratio was significantly lower in flours made from aphid infected wheat seeds, it may be suggested that aphid feeding results in decreased bread making quality of wheat flour.

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Winery wastewater treatment plants generally face severe nutrient deficiency, and therefore conventional technologies and supplementary nutrient dosing strategies may fail. The purpose of the paper is to show how traditional way of dosing N-source for marginal availability to nutrient deficient influents results in poorly settling activated sludge regardless of the application of aerated or non-aerated selectors. External N-source calculated for marginal availability resulted in nutrient deficiency due to the relatively high yield experienced (0.7 g biomass COD/g substrate COD). In the fully aerated system with overall N-deficiency, rapidly increasing overproduction of extracellular polysaccharide was experienced, leading to SVI (Sludge Volume Index) values up to 600 cm3 g−1. In the system with the non-aerated selector, initial nutrient deficiency could only be detected in the second reactor. Since neither overgrowth of floc-forming GAOs (Glycogen Accumulating Organisms) nor denitrification could be experienced, the non-aerated reactor operated as low-DO (Dissolved Oxygen) basin, attributing to the drastic overgrowth of filamentous bacteria leading to SVI values >1000 cm3 g−1. Since dosing external N-source for marginal availability is likely to cause severe biomass separability problems in activated sludge winery wastewater treatment, either pronounced N-overdosing and pre-denitrification or severe nutrient deficiency and GAO cultivation can rather be recommended.

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Authors: B. Bolla, G. Fehér and K. Kiss
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Two wheat-infecting isolates of WDV-WDV-B and WDV-F- were collected in the field of Martonvásár and Nagykovácsi. The complete genomes were amplified by PCR, cloned into pBKS+ plasmid and sequenced. The nucleotide divergence in the total genome of the five isolates-WDV- Fra, WDV-Cz, WDV-Swe, WDV-B and WDV-F-originating from different part of Europe were found to be 0.44-1.69%. The four genes- MP, CP, RepA and Rep-and two non-coding region-LIR and SIR- were compared and a phylogenetic tree was constructed.

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Flour from grains originating from plants infected artificially with cereal aphids were analyzed for glutenin and gliadin and total protein content, using Size Exclusion HPLC. Wheat plants were caged at the beginning of stem elongation. Cages were treated with 0.1 % methyl parathion. One week later, the caged plants were artificially infected with 5 aptera individuals of Metopolophium dirhodum, Diuraphis noxia, Sitobion avenae and Rhopalosiphum padi . It was found that aphid infection had significant effect on the glutenin and gliadin content, the total protein content and the gliadin/glutenin ratio. Both the glutenin and gliadin content was significantly higher in the seeds harvested from aphid infected plants. However, the gliadin/glutenin ratio was significantly lower in wheat flour prepared from aphid infected plants than in those from uninfected control. The most significant decrease in gliadin/glutenin ratio was caused by M. dirhodum, D. noxia, S. avenae infection followed by R. padi at high-abundance. As the gliadin/glutenin ratio was significantly lower in flours made from aphid infected wheat seeds, it may be suggested, that aphid feeding results in decreased bread making quality of wheat flour.

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