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Private pension funds were thought to be an important pillar of old-age provision when they were introduced throughout (Emerging) Europe. As different as these funds are in different countries with regards to their regulation, their ownership structure and operation, none were immune to the sub-prime led financial crisis. The Hungarian private pension funds are unique amongst the defined contribution (DC) funds. With their decade old recent history, they are maturing to the payout period in a few years’ time; however, their demise appears ever more realistic by means of political decision. This makes uncovering their investment policy during the crises very timely. Examining such a period is of importance in shedding light on the behaviour of traditional financial concepts in periods of stress. In this paper, we assess the optimality of diversification, hedging and short sales decision possibilities of the Hungarian pension funds in the equity investments environment. Was the net asset value (NAV) erosion suffered by the Hungarian private pension funds a result of their investment decision? We examine this question of diversification through a hypothetical simulation of model investment portfolios. Our results show that international diversification yields better risk-adjusted returns only in case of perfect hindsight of future market movements. The high correlation of the stock indices globally in times of crises limits the benefits of diversification.

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Sweet cherry fruits ( Prunus avium cv. Vera, Carmen, Linda and Krupnoplodnaja) were harvested in different ripeness stages after anthesis 39, 42, 49, 56 days (Carmen); 37, 40, 47, 52, 59 days (Krupnoplodnaja); 32, 36, 44, 53, 58 days (Linda); 38, 42, 50, 52, 57 days (Vera). The colour, total soluble solids, dry matter content, β-galactosidase and polygalacturonase activity were determined. The dry matter content and total soluble solids content (Brix o ) increased during development. The L* values significantly decreased as a function of ripening while a* values increased up to 3 rd harvest, then they decreased, b* values continuously decreased as a function of development. The a*/b* values linearly increased as a function of development, indicating reddening of fruits. Hue angle (h o ) increased rapidly between harvest one and two. The measured (a*, b*, L*) and calculated parameters (h o , a*/b*, chroma) well represented the colour development of sweet cherries. Linear and strong correlation was found between a*/b*, L* values and the Brix o , exponential correlation was found between h o , chroma and Brix o . Activity of β-galactosidase was different among cultivars and as a function of development. The two maximums might β-galactosidase isoenzymes. The role of PG (polygalacturonase) could not be explained clearly enough, further investigations are needed to find the exact role of the enzyme in the cell wall metabolism of sweet cherry.

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Authors give a report on four eriophyoid species which were new for the Hungarian fauna (Aculops berochensis Keifer and Delley; Aculops parakarensis Bagdasarian; Aculus ligustri Keifer; Aculus? crataegumplicans Cotte). Three of them were found on new host-plants.

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The phase changes in the solid state in E AlMgSi alloy are discussed. The dissolution and precipitation processes are investigated by DTA, and the results can be applied to control the technological parameters of dissolution heat treatments.

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Acta Alimentaria
Authors: E. Kovács, P. Merész, Z. Kristóf, and E. Németh-Szerdahelyi

Colour, texture, pectin autolysis, membrane permeability and microstructure (SEM, TEM), β-galactosidase and polygalacturonase were studied in apricots (cv. Magyar kajszi) harvested in mature green, straw yellow, bright orange and deep orange stages. The L* increased from mature green to straw yellow then decreased from straw yellow to deep orange state. The a* values increased with ripening. The bright and deep orange apricots were significantly softer than the mature green and straw yellow ones and the membrane permeability increased with ripening. The presence of β-galactosidase enzyme was proved by immunoblotting analysis using monoclonal anti-β-galactosidase clone GAL-13 (Sigma) in all ripening stages. The enzyme activity was very low in mature green stage and increased significantly (P>95%) with increasing ripeness and during storage. The PG activity was very low in the mature green apricot. A significant (P>95%) increase was observed in the straw yellow apricot and in the riper fruits. The mature green apricot showed a regular, the straw yellow and bright orange samples showed a moderately regular tissue structure, while the tissue of the deep orange apricot collapsed (SEM). The cell wall and the middle lamella of the green apricot (TEM) were intact. Generally, there were intact cytoplasm membranes with some damaged parts. In the straw yellow apricot, the cell wall started to loosen, the middle lamella lost pectic polysaccharides. The structure of the cytoplasm was not recognisable, the tonoplast and the cytoplasm membrane were injured. The cell wall of the bright orange apricot was similar to that of the straw yellow ones. The middle lamella dissolved and hairy, fibrillar structure of cell wall was found in the deep orange samples.

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Community Ecology
Authors: E. Lellei-Kovács, E. Kovács-Láng, T. Kalapos, Z. Botta-Dukát, S. Barabás, and C. Beier

The influence of simulated climate change on soil respiration was studied in a field experiment on 4 m × 5 m plots in the semiarid temperate Pannonian sand forest-steppe. This ecosystem type has low productivity and soil organic matter content, and covers large areas, yet data on soil carbon fluxes are still limited. Soil respiration rate — measured monthly between April and November from 2003 to 2006 — remained very low (0.09 — 1.53 μmol CO 2 m −2 s −1 ) in accordance with the moderate biological activity and low humus content of the nutrient poor, coarse sandy soil. Specific soil respiration rate (calculated for unit soil organic matter content), however, was relatively high (0.36–7.92 μmol CO 2 g −1 C org h −1 ) suggesting substrate limitation for soil biological activity. During the day, soil respiration rate was significantly lower at dawn than at midday, while seasonally clear temperature limitation in winter and water limitation in summer were detected. Between years, annual precipitation appeared to be important in determining soil carbon efflux intensity. Nocturnal warming increased soil temperature in 1 cm depth at dawn by 1.6°C on the average, and decreased topsoil (0–11 cm) moisture content by 0.45 vol%. Drought treatment decreased soil moisture content by an average of 0.81 vol%. Soil respiration rate tended to decrease by 7–15% and 13–15% in response to heat and drought treatment, respectively, although the changes were not statistically significant. Nocturnal warming usually prevented dew formation, and that probably also influenced soil respiration. Based on these results, we expect a reduction in the volume and rate of organic matter turnover in this ecosystem in response to the anticipated climate change in the region.

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Acta Alimentaria
Authors: E. Szabó, É. Gelencsér, E. Kovács, A. Jánosi, K. Takács, and E. Kiss

In our research we studied the occurrence of the main apple allergen coding gene-families (Mal d 1, Mal d 2, Mal d 3, Mal d 4) in 16 different and most preferably consumed apple varieties. After the DNA isolation by Wizard method the simple PCR reaction was used to examine the apple allergen-coding genes. To identify the presence of the four allergenic protein-coding genes two primer pairs were chosen. The presence of these allergens in most apple varieties could be confirmed. According to our results two varieties — Jonathan and Granny Smith — were found to contain the lowest amount of the coding genes of the allergenic apple proteins studied by us. Besides this, polymorph pattern was obtained by the use of Mal d 1 primer, which may lead to determine apple varieties with small amount of Mal d 1 allergens.The confirmation study of the presence of potential apple allergens by RNA and protein techniques is our plan in the near future.

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Volatile flavour substances were isolated from the minced pulp of half ripe and full ripe fruits of guava (Psidium guajava L.) cv. Lucknow-49 by simultaneous steam distillation extraction (SDE) with diethyl ether as extracting solvent. The concentrate was analysed by GC-MS. Acetic, butyric and hexanoic acids were the predominant acids, trans-2-hexenal and hexanal the predominant aldehydes and ethyl propanoate, methyl butyrate, ethyl butyrate, methyl hexanoate, ethyl hexanoate, cis-3-hexen-1-yl acetate, hexyl acetate, methyl benzoate, methyl octanoate, ethyl benzoate, phenylpropyl acetate and cinnamyl acetate, the esters responsible for the characteristic guava flavour were also present. The amount of total volatile substances was about 20% higher in full ripe fruits. The concentration of acids and most esters increased and that of C6 aldehydes decreased during ripening. The enzyme analysis showed that the polygalacturonase (PG) activity was lower in the ripe fruit, than in the half ripe one, while the β -galactosidase activity was not influenced by maturity stage. The surface and the cell walls of full ripe guava became wrinkled, and parenchyma cells were empty (SEM).

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In this study, we examined the relationship between levels of lactoferrin (LF) and IL-17 in human serum and breast milk and the development of allergy in children. LF and IL-17 levels were determined by ELISA in healthy (n=19) and allergic mothers (n=21) on the 5th day after delivery. Two years later, information on breastfeeding and allergic outcomes was collected by questionnaires from parents of both groups and district child care nurses. Significantly higher concentrations of LF were found in the breast milk of allergic mothers compared to the healthy controls. At 2 years of age, only those three infants became allergic from the atopic group in whose starting breast milk samples a very high LF level (306 μg mg–1 protein) or simultaneously elevated concentrations of LF and IL-17 were measured. These findings indicate that the very early measurement of LF and IL-17 levels in the breast milk of allergic mothers may help to predict the allergy development in their infants.

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