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In this paper we provide a comprehensive summary about the practical results of the OTKA project K49604. 1. We calculated the consequences of incorrect positioning of the electrodes for various multielectrode systems. In practice these effects were found to be negligible. The only exception is the case of rocky surface, where it is impossible to put the electrodes in the desired positions. The errors can however be kept within an acceptable range, if the electrodes of the linear arrays are put off-set, at right angles from the measuring line. A five-six times larger off-set has less effect than a certain mis-position along the line, connecting the electrodes. 2. We carried out tensorial geoelectric measurements around the Cistercian Monastery at Pilisszentkereszt. Areal measurements provide much more detailed and unambiguous anomalies than 2D profile measurements, and the tensor invariant representation of apparent resistivity anomalies provides a realistic picture about the lateral variation of the subsurface resistivity, even in field circumstances. 3. We tested the applicability of 3D electrical resistivity tomography (ERT) technique to detect landmines in different soil conditions and at various depths. Metallic and non-metallic landmines buried in wet and dry soils had been synthetically modeled. According to the inverted resistivity data using the dipole axial array in wet environment, it was possible to locate the metallic and non-metallic landmines as long as the noise level was about 5%. 4. We elaborated moreover a geoelectrical procedure which is able to map multidirectional fissure systems by combining geoelectrical profiling and geoelectrical azimuthal measurements. Results received by using both the so-called null-, and traditional arrays were jointly interpreted. The humidity of the fissures affects the measured results significantly, and in a meaningful way. 5. We presented the socalled standardized pricking probe (PP) surveying technique and demonstrated its usefulness in an archaeological study. The PP images proved to be definitely more close to the realistic shape of the buried chapel than the geoelectric and magnetic measurements, and they also revealed more details about the subsurface than the georadar. The optimum PP parameters: horizontal interval, pricking depth, observable quantity and its way of presentation were optimized through field experiments. For more details see the cited publications. The figures ever published in Hungarian journals are not reproduced here.

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Current wisdom describes the immune system as a defense against microbial pathogens. It is claimed that the virgin immune system has a capacity to produce antibodies against the entire antigenic universe. We assume, by contrast, that the responding capacity of the immune system is limited. Thus it cannot stand in readiness to deal with a practi- cally endless diversity and abundance of microbes. Axioms and theorems are suggested for a mathematician audience delineating how the immune system could use its limited resources economically. It is suggested that the task of the immune system is twofold: (i) It sustains homeostasis to preserve the genome by constant surveillance of the intracellular antigenic milieu. This is achieved by standardization of the T cell repertoire through a positive selection. The driving force of positive selection is immune cell survival. T cells must constantly seek contact with complementary MHC structures to survive. Such contact is based on molecular complementarity between immune cell receptors and MHC/self-peptide complexes. At the highest level of complementarity a local free energy minimum is achieved, thus a homeostatic system is created. Homeostatic interactions happen at intermediate afinity and are reversible. Alteration in the presented peptides typically decreases complementarity. That pushes the system away from the free energy minimum, which activates T cells. Complementarity is restored when cytotoxic T cells destroy altered (mutated/infected) host cells. (ii) B cells carry out an immune response to foreign proteins what requires a change in the genome. B cells raised under the antigenic in uence of the normal intestinal micro o- ra, self-proteins and alimentary antigens must go through a hypermutation process to be able to produce specific antibodies. It has a certain probability that hypermutation will successfully change the genome in some clones to switch from low afinity IgM antibody production to high afinity IgG production. Interactions (typically antibody antigen reac- tions) in an immune response happen at high afinity and are irreversible. High afinity clones will be selected, stimulated and enriched by the invading microbes. A complete account of the course of an infectious disease must also include a descrip- tion of the ecology of the immune response. It is therefore suggested that during prolonged interaction between host and infectious organism, carried on across many generations, the adaptive antibody population may facilitate the evolution of the natural antibody reper- toire, in accordance with the Baldwin effect in the evolution of instinct (see Appendix 6).

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The anthocyanin content of spring and winter wheat cultivars and their hybrids with purple and blue coloured grains was evaluated under Hungarian growing conditions. In all 3 years the anthocyanin content of blue grained wheats was significantly higher than that of purple ones. Anthocyanin content was influenced by environmental factors. In the progenies of crosses between Hungarian hard red winter wheat cultivars and blue-grained varieties, the anthocyanin content of the grind was 21–157 mg/kg, while that of the flour was 5.3–17.4 mg/kg. Consequently, most of the anthocyanin content was in the bran. The high anthocyanin content of blue and purple wheat varieties can be applied successfully for elevating the anthocyanin content of bakery products if whole-meal flour or bran is used.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
L. Varga
,
L. Liszkay
,
Zs. Kajcsos
,
K. Lázár
,
H. Beyer
,
G. Onestyák
,
E. Kótai
, and
L. Lohonyai

Abstract  

In many sorts of zeolites long-living positron components are manifested, connected presumably with Ps-formation in various kinds of free space in the zeolite structure. Literature values demonstrate, however, a broad scasttr of data obtained for assumedly on the same composition of zeolite indicating the possible influence of tehnology, adsorbates, impurities, water content, etc. In the present work spectral changes of the 511 keV annihilation peak and its vicinity are evaluated, applying for the first time a combination of theS and W parameters and the 3-specific left plateau region measured in zeolites. To ensure reproducible experimental conditions, evaluated samples were measured. The data show individual temperature behaviours of the annihilation parameters in the studied temperature range of 90–450 K for each kind of samples. The temperature dependence becomes reproducible after the first heating run. The results are discussed with respect to the evolution of long-living positron and positronium components.

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Clinical, bacteriological and serological examination of 35 calves from the age of 5 to 26 days was performed in a Holstein-Friesian dairy herd endemically infected with Mycoplasma bovis. M. bovis was isolated from 48.6% of nasal swabs taken from the calves at the age of 5 days, and from 91.4% of the same calves at the age of 26 days, indicating the gradual spread of infection. The isolation rate of Pasteurella multocida did not change much, and varied from 28.6 to 25.7%. No P. haemolytica could be detected. In addition to M. bovis and P. multocida, the herd was also infected with different viruses (including bovine viral diarrhoea virus, infectious bovine rhinotracheitis virus, bovine adenoviruses, parainfluenza-3 virus, and bovine respiratory syncytial virus) as a large proportion of the sera of newborn calves contained colostral antibodies against these viruses. In most of the newborn calves severe clinical signs (fever, depression, inappetence, hyperventilation, dyspnoea, nasal discharge and coughing) due to M. bovis infection developed. The clinical signs appeared already on the fifth day of life, and their incidence was the highest at the age of 10 to 15 days. Three calves (8.6%) died as a result of severe serofibrinous pneumonia. The surviving calves showed very poor weight gain (ranging from 1.5 to 3.5 kg) during the first two weeks of life.

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Thirty-three varieties of dairy products were analysed for fat and cholesterol contents, and a high correlation (r=0.983) was found between these two compositional attributes. Cholesterol concentration was independent of processing factors such as heat-treatment of the raw material, use of starter culture, type of the starter organisms employed and whipping or flavouring of the product. The non-fat varieties of fluid, fermented and dried milks showed significantly increased cholesterol-to-fat ratios compared to the other products tested because they contained considerable amounts of small fat globules and, therefore, had a large surface area with cholesterol bound to the fat globule membranes. The results of this study may be useful when establishing dietary guidelines for the general public according to health concerns, when formulating diets for population groups with special requirements or when assessing fat and cholesterol intakes in epidemiological studies aimed at investigating the relationship between diet and health.

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Abstract

In this study, a systematic study of the effect of the temperature on the density and surface tension of HMT (hexamethylentetramine) in water was developed. The density and surface tension were determined at temperatures of 288.15, 293.15, 298.15, 303.15, and 308.15 K. Precise data of surface tension have not been reported previously in literature. From the density measurements, the apparent molar and partial molar volumes were calculated. The apparent molar volume decreases with concentration, the molar partial volume increases with temperature. The surface tension of the aqueous solutions of HMT decreases with concentration. The excess surface concentration was calculated, the values increase with concentration, indicating that the amount of HMT that goes to the interface gas liquid increases at higher concentrations of HMT.

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Abstract

Immersion enthalpies of activated carbon samples obtained by activation with steam at temperatures between 600 and 900 °C and activation times between 1 and 10 h were determined. The calorimetric liquids of immersion are CCl4, water, NaOH, and HCl 2 M solutions, and the values of the immersion enthalpies are related to other properties of the activated carbons such as the surface area B.E.T., the micropore volume, the content of acid, and basic surface groups. The highest values for the immersion enthalpies take place for the polar solvent CCl4 and for HCl solution, with values between 4.0 and 75.2 J g−1 and 9.15 and 48.3 J g−1, respectively.

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Basket willow (Salix viminalis L.) was grown in open-field experiment. The brown forest soil (sand texture, pHKCl 7.7, humus 1.6%, CEC 11.5 cmolc/kg; Cd-0.11, Cu-7.1, Pb-8.1, Zn-25.0 mg/kg in aqua regia extract) was treated with municipal sewage sludge compost (MSSC) (25 t/ha wet weight, 12.8 t/ha dry weight in 2009; 50 and 100 t/ha wet weight, 25.4 t/ha and 50.8 t/ha dry weight in 2008). The MSSC was moderately contaminated with toxic metals (Cd-<0.5, Cu-140, Pb-19, Zn-440 mg/kg in aqua regia extract in 2008, and Cd-<0.5, Cu-299, Pb-69, Zn-865 mg/kg in aqua regia extract in 2009). Accumulation of Zn in treated willow leaves doubled 4 months after 25 t/ha MSSC application, while in treated twig tips 30% less Zn was found than in control. Zn (max. 133 mg/kg d.w.), Cd (max. 1.15 mg/kg d.w.) and Cu (max. 7.73 mg/kg d.w.) accumulations in leaves or twig tips of basket willow were 16 months after 50 or 100 t/ha MSSC application. Twenty months after MSSC application in the harvested twigs (shoots without leaves) of 50 or 100 t/ha MSSC-treated cultures the Zn concentrations were only 9.8–14.3% higher than in controls. We suppose that there is not a direct danger of considerable Zn accumulation in the bioash after incineration of MSSC-treated willow shoots in biomass power plants.

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Biofertilizers are used to improve soil fertility and plant production in sustainable agriculture. However, their applicability depends on several environmental parameters. The aim of our study was to evaluate the effect of free-living bacteria containing fertilizer on the growth of cucumber (Cucumis sativus L. cvs. Delicates) under aluminium (Al) stress. Different responses to Al stress of cucumber growth parameters were examined in terms of root elongation and physiological traits, such as Spad index (relative chlorophyll value), biomass accumulation of root and shoot, Al uptake and selected element contents (Fe, Mn, Zn, Mg) of leaves and root. The applied bacteria containing biofertilizer contains Azotobacter chroococcum and Bacillus megaterium. The dry weights of cucumber shoots and roots decreased in line with the increasing Al concentration. Due to different Al treatments (10−3 M, 10−4 M) higher Al concentration was observed in the leaves, while the amounts of other elements (Fe, Mn, Zn, Mg) decreased. This high Al content of the leaves decreased below the control value when biofertilizer was applied. In the case of the roots the additional biofertilizer treatments compensated the effect of Al. The relative chlorophyll content was reduced during Al-stress in older plants and the biofertilizer moderated this effect. The root/shoot ratio was decreased in all the Al-treatments in comparison to the control. The living bacteria containing fertilizer also had a modifying effect. The root/shoot ratio increased at the 10−4 M Al2(SO4)2 + biofertilizer and 10−4 M Al(NO3)3 + biofertilizer treatments compared to the control and Al-treatments. According to our results the biofertilizer is an alternative nutrient supply for replacing chemical fertilizers because it enhances dry matter production. Biofertilizer usage is also offered under Al polluted environmental conditions. Although, the nutrient solution is a clean system where we can examine the main processes without other effects of natural soils. The soil can modify the results, e.g. the soil-born microorganisms affect nutrient availability, and also can modify the harmful effects of different heavy metals. The understanding of basic processes will help us to know more about the soil behaviour.

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