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The food industry is in the crossfire of increasing pressure of competition, consumer demands, and growing importance of ecological sustainability considerations. Life cycle analysis is one of the most important methods for evaluation of environmental effects of food industrial technologies and packaging systems. During the last decades there have been an intense work to collect pieces of information on different environmental aspects of food packaging systems all over the world, but there is a considerable gap between the amount of knowledge and its practical application in decision making on the level of enterprises as well as in the process of determination of environmental protection fee. Application of modern, freely available software frameworks for life cycle analysis offers a favourable possibility for integration of environmental information into managerial and governmental decision making processes. Based on case studies, the article demonstrates the possibilities of utilisation of cumulative environmental burden indicators as well as expert decision-support systems for optimisation of product-portfolio, based on environmental considerations.

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Changes in the chemical contents of the kernels of maize hybrids were analysed in three consecutive years (one dry, one arid and one wet) in samples originating from irrigation and fertilisation experiments. The results indicated that while irrigation and wet years had a protein-decreasing effect, the water supply did not influence the starch and oil contents. Under the influence of fertilization, the calcium and zinc contents of maize kernels decreased to varying degrees depending on the hybrid, while the sulphur contents changed parallel to the protein contents. Based on these data and on the use of more modern measuring equipment, tables giving recommendations for chemical contents should be revised.

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In field screening tests conducted on selected pest scarabaeids in Hungary, Epicometis (Tropinota) hirta (subfamily Cetoniinae) was attracted to traps baited with either cinnamyl alcohol or trans-anethol. In some tests attraction was also detected to phenethyl alcohol or cinnamyl acetate. In other tests, adults of Cetonia aurata aurata and Oxythyrea funesta (subfamily Cetoniinae) also were attracted to trans-anethol, while the ternary mixture of phenethyl propionate, eugenol and geraniol attracted Potosia cuprea (subfamily Cetoniinae). Some attraction of Valgus hemipterus (subfamily Valginae) to cinnamyl alcohol also was observed. All of the above species are pests of more or less economic importance in Hungary. The attractant chemicals discovered in the present study will form a starting point for the development of effective attractants for the respective pest scarab species.

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Acta Agronomica Hungarica
Authors: Z. Hegyi, Z. Zsubori-Tóth, J. Pintér, and C. Marton

Experiments have been underway in Martonvásár for many years to develop leafy silage hybrids, which have a greater aboveground mass than conventional silage hybrids. The best hybrids for biogas production would be those that produce a large quantity of biomass and are rich in starch. The chief characteristic of leafy hybrids is that they have more leaves than normal hybrids. Due to this enhanced leaf area above the ear, the vegetative period of leafy genotypes is shorter, while the grain-filling period is longer, which has a positive effect on both yield and grain quality. The results of the present experiment show that during the anaerobic fermentation of the silage, leafy hybrids produced more biogas (640 l per 1000 g dry matter) than conventional hybrids (606 l per 1000 g dry matter). There were no significant differences between the methane contents of the leafy and non-leafy hybrids tested in the experiment. A strong positive correlation was found between biogas yield and the starch content of the silage, and a moderate positive correlation between biogas yield and the sugar content. The correlation between biogas yield and the lignin and protein contents was negative, in accordance with other literary data.

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The ubiquitin (Ub)- proteasome proteolytic system is highly selective, and the specific proteins involved in cell division, growth, activation, signaling and transcription are degraded at different rate depending on the physio-pathological state of the cell. Ubiquitination serves first of all as a signal for protein degra- dation of short-lived and abnormal proteins under several stressful conditions. The immunocytochemical localization of Ub in some malignant tumours has recently been presented and differences in Ub expres- sion has been observed during malignant transformation. Change in the level of Ub and Ub-conjugated proteins might reflect a higher metabolic-catabolic ratio in neoplastic cells. Most studies have been focused on the malignant stage of tumour progression, and only a few papers have dealt with the change in Ub and Ub-protein conjugates level during the whole progression. To address this problem, we applied an azaserine-induced pancreatic carcinogenesis model, in which premalignant and malignant stages were investigated throughout the progression. The level of Ub immunoreactivity was measured in nucleus and cytoplasm by electron microscopic immunocytochemical and morphometrical methods. We found a sig- nificant increase of Ub level in the nucleus and the cytoplasmic area in premalignant atypical acinar cell nodule (AACN) cells and in malignant adenocarcinoma in situ (CIS) cells at month 20 after initiation.

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Growth regulation is a crucial event in tumour progression. Surprisingly, relatively few papers have dealt with the catabolic side of regulation, and there are practically no data regarding the autophagic process during tumour development. We approach this problem by morphometrical investigation into the possi- ble changes of autophagic activity during the progression of rat pancreatic adenocarcinoma induced by azaserine. In the present study, autophagic capacity of the azaserine-induced premalignant and malignant cells were characterised and compared to the respective host tissue cells of the rat pancreas and to the acinar cells in other stages of tumour development. Using vinblastine (VBL) as an enhancer, and cyclo- heximide (CHI) as an inhibitor of autophagic segregation we observed that autophagic capacity of pre- malignant cells (month 6 and 10 after initiation) is much higher than in the host tissue cells. We found a sharp decrease in self-digesting capacity in adenocarcinoma cells (month 20) where VBL induced a min- imal accumulation of autophagic vacuoles which was, surprisingly, not inhibited by CHI, i.e. the CHI- sensitive regulatory step was lost. The changes in autophagic capacity are probably associated to specif- ic steps of tumour progression in our system.

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The effect of four NPK fertilizer rates (NPK[1:1:1]: 0, 300, 600, 900 kg active ingredients·ha -1 ) was studied on the growth of maize and on weed infestation - bio-mass production and nutrient uptake of weeds - in four replications in a 35-year old long-term maize continuous cropping field experiment (Keszthely, Hungary). The weed flora was recorded on 1 June, 2003 in the 6-8-leaf development stage of maize. The effect of the increasing rates of fertilizers was analyzed and evaluated from the results of biomass production as well as the nutrient uptake of weeds and maize, respectively. On the experimental plots 9 weed species were registered at the date of sampling, from which 4 species were perennial and 5 species were annual ones. All the weeds were collected from 1 m² areas of each plot and the different weed species were separated from each other. The fresh and dry weights of the canopy of maize and the different weed species were measured. The nutrient (NPK) contents of maize and weed samples were measured in the laboratory. Total and species scale nutrient concentration, as well as per-unit nutrient uptake of maize and weeds were compared. The increasing rates of mineral fertilizers had a significant effect on the biomass production and on the nutrient uptake of weeds. Significant differences were also found between the biomass production and nutrient uptake of the different weed species.

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Western corn rootworm (WCR) ( Diabrotica v. virgifera Le Conte) (Coleoptera, Chrysomelidae) adults were attracted only during daytime hours and showed a bimodal diel activity pattern when responding to the synthetic floral bait in the field. On the other hand, to the synthetic pheromone bait, good responses were recorded apart from daytime hours also well into the night. The present results suggest that in WCR the pheromonal communication channel and the channel connected with feeding (= floral lure) are separated.

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Several synthetic floral lures have been described for the cetoniin scarabs Cetonia aurata aurata L. and Potosia cuprea Fabr. (Coleoptera, Scarabaeidae), exploiting their olfaction-guided behavioural preference for a wide range of flower volatiles.

A ternary mixture of 3-methyl eugenol, 1-phenylethanol and (E)-anethol has previously been described as a powerful synthetic floral attractant for both C. a. aurata and P. cuprea. The first objective of the present research was to test whether isoeugenol and eugenol, with a very similar molecular structure to 3-methyl eugenol, can substitute 3-methyl eugenol in the ternary blend. All baited traps caught significantly more of both species than unbaited control traps, however, traps containing 3-methyl eugenol caught significantly more than those with either isoeugenol or eugenol. This indicates a fine tuning in behavioural response to 3-methyl eugenol.

The second objective was to devise simpler attractant combinations for C. a. aurata and P. cuprea, based on previous field studies with synthetic floral compounds. Both C. a. aurata and P. cuprea showed strong attraction to the combination of 2-phenylethanol and 4-methoxyphenethyl alcohol, while the combination of 2-phenylethanol and 1,2,4-trimethoxybenzene resulted in medium-size catches, however, mostly catching P. cuprea. This level of selectivity may lead to the development of more selective lures for P. cuprea, and provide a better understanding of the feeding-related olfactory ecology of the two important pest chafer species.

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Low velocity surface layers can significantly increase ground accelerations during earthquakes. When saturated sandy sediments are present, because of pore pressure increase, decrease of soil strength or even liquefaction can occur. Some volume change follows the dissipation of excess pore pressure after the earthquake resulting surface settlements. To determine the liquefaction probability and post-liquefaction settlement is very important for critical facilities e.g. for the site of Paks Nuclear Power Plant, Hungary. Pore pressure increase and so the liquefaction and surface settlements depend on the characteristics of seismic loading and soil parameters. To quantify the extent of these phenomena is rather difficult. Uncertainties arise both from the probabilistic nature of the earthquake loading and from the simplifications of soil models as well. In the paper, the most important semi-empirical and dynamical effective stress methods for liquefaction and post-liquefaction settlement assessment are summarized. Most significant contributors to the uncertainties are highlighted, and particular examples through the investigation of Paks NPP site are given. Finally, a probabilistic procedure is proposed where the uncertainties will be taken into account by applying a logic tree methodology. At the same time, the uncertainties are reduced by the use of site-specific UHRS and stress reduction factors.

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