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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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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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Functional morphology of Helix pomatia salivary gland cells was studied at light microscopic level by using different histochemical methods. Three cell types could be demonstrated in the salivary gland: mucocytes, granular and vacuolated cells. The distribution and the number of the different cell types were different in active and inactive snails. In active feeding animals, dilatated interlobular salivary ducts were observed, which were never present in inactive ones. In active animals an additional cell type, the cystic cell could also be observed. Periodic acid Schiff staining revealed both mucuos and serous elements in the salivary gland. Furthermore, hematoxyline-eosin staining indicated the occurrence of a cell layer with high mitotic activity in the acini. Applying immunohistochemical methods with monoclonal mouse anti-human Ki-67 clone, B56 and polyclonal rabbit anti-human Ki-67 antibodies, we also were able to demonstrate the occurrence of dividing cells in the salivary gland. Analysis of 1-2 µm semi-thin Araldite sections stained with toluidine-blue showed that the saliva can be released, in addition to possible exocytosis, by the lysis of cystic cells. Using an apoptosis kit, we could also establish that this process was due to rather an apoptotic than a necrotic mechanism. In the salivary gland of active snails, where an intensive salivation takes place, significantly more apoptotic cells occurred, if compared to that of inactive animals. It is suggested that programmed cell death may also be involved in the saliva release.

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Acta Alimentaria
Authors:
Zs. Kiss
,
Sz. Kertész
,
C. Hodúr
,
G. Keszthelyi-Szabó
, and
Zs. László

Nowadays, the membrane filtration technique is a commonly used method for the separation of whey. The most significant limitation of membrane applications is fouling, which causes flux decline. During this work, regenerated cellulose membranes covered by TiO2-nanoparticles were investigated and applied to the separation of whey solution. Experiments were carried out in a dead-end ultrafiltration cell, and the changes in filtration parameters and the photocatalytic effects of the UV irradiated TiO2 modified membrane surface on the membrane fouling were examined. Our results showed that the water flux decreased with increasing TiO2 layer thickness, but the retention of turbidity and of COD increased. After separation, the membrane surface was cleaned by UV irradiation by means of photocatalytic oxidation. It was found that the original flux was recoverable, while the retention of the membrane decreased after cleaning.

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Acta Botanica Hungarica
Authors:
K. T. Kiss
,
Zs Trábert
, and
M. Duleba
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Acta Botanica Hungarica
Authors:
K. T. Kiss
,
Zs. Trábert
, and
M. Duleba
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The pot experiment - carried out in 2000 under greenhouse conditions - was set up with seven soils differing in Cd and Pb contents and three test plants ( Lolium perenne L. cv. Georgikon), lettuce ( Lactuca sativa L. cv. Balatonzöld) and white mustard ( Sinapis alba L. cv. Sirola) with four replicates. From the seven experimental soils five samples (S1-S5) were collected from agricultural areas (arable sites) and two (S6-S7) from spoil-earth, with extremely high Cd and Pb contents.  The pots, each containing 1 kg air-dry soil, were kept at constant soil moisture (60% of maximum water capacity of the experimental soils) by daily watering, while pots were watered to weight once weekly. Before sowing the test plants: 50-50-50 mg N, P 2 O 5 and K 2 O was applied to the experimental soils to maintain the same nutrient supply. The above-soil plant parts were cut after four weeks. Fresh and dry weights of plants were determined after harvest. The aim of the experiment was to obtain results of Cd and Pb uptake by different plant species in relation to the heavy metal content and different characteristics of soils. The following conclusions were drawn: No definite correlation was found between the biomass production of the three test plants and the heavy metal content of the soils at early growth stage. The heavy metal concentration range in the soils and plants differed. In the case of Pb the soil concentration interval was broader than that of the plants'. The opposite was observed for Cd, where the plants had a wider concentration interval. Comparing the Pb and Cd concentrations of above-ground plant parts, Pb concentrations varied in a narrower interval. The maximum values of Pb content exceeded the Cd content levels, although the mobility of Pb in the soil-plant system is significantly lower. The comparison of Cd and Pb concentrations of plants and soils proved these differences. The Cd concentration of plants was 8-231% of the total Cd content of soils. The Pb concentration of plants was the 0.8-28% of the total Pb content of the soils, respectively. Comparing the three plants in respect of Cd concentrations the order found was as follows: ryegrass < white mustard < lettuce. In case of Pb, the order depended on the Pb content level (lower or higher) of the experimental soil. Symptoms of phytotoxicity were observed only on lettuce plants grown on the contaminated soils (S6, S7).

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Abstract  

The purpose of the present work was to study the compatibility of metronidazole with different pharmaceutical excipients (hydroxypropyl methylcellulose, poly(ethylene oxide), microcrystalline cellulose, dicalcium phosphate dihydrate, and anhydrous dicalcium phosphate) using differential scanning calorimetry and diffuse reflectance spectroscopy. Dicalcium phosphate dihydrate was the only excipient that showed interaction with metronidazole even before storage. Changes referring to a possible transition to dihydrate form were observed in the thermal curves of anhydrous dicalcium phosphate after four weeks of storage. Although dicalcium phosphate dihydrate can be replaced by the anhydrous form in pharmaceutical formulations, the observed transition might negatively influence the stability of dosage forms.

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