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  • Author or Editor: Z. Kovács x
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Abstract  

Pseudoconnections (or quasi connections) were defined as a generalization of linear connections by Y.-C. Wong in [14], and were developed mainly by Italian and Rumanian mathematicians. The purpose of this paper is to study some properties of a special type of pseudoconnections: the so-called associated pseudoconnections oginirating from linear connections in a very simple manner. In 1 we give a necessary and sufficient condition for a pseudoconnection to be associated, the in 2 we study the geodesics of an associated pseudoconnection. This notion has an immediate application in Finsler geometry, this is the theme of 3. Some questions connecting the curvature of associated pseudoconnections were studied by the author in [7].

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Abstract  

Volatilization and thermochromatographic separation of ultramicro amounts of Mo and Tc from AgCl melt irradiated with 6 60 MeV protons have been studied in vacuum at 600 °C. It has been found that in quartz apparatus Tc, and while using graphite, Mo can be separated from the other leaving elements. On the basis of the experimental results an ion source can be contructed for the on-line nuclear spectroscopic studies of Mo and Tc isotopes.

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Discovering the relationships among plant morphological and quantitative features is very important in maize breeding and production, particularly if they can be altered by selection or agro-technical methods. We examined tassel characteristics (tassel weight, tassel stalk diameter, number of primary branches, total length of branches, tassel length from lower and upper branches, Tassel Area Index) and several quantitative features (plant height, ear height, LAI, number of leaf, yield, 1000-kernel weight, test weight) of 12 hybrids in randomized block design during two subsequent years on two locations. Our aim was to find correlation between traits. Tassel weight was positively correlated with total number of branches (0.59**), number of primary branches (0.53**) and tassel area index (0.63**), and negatively correlated with plant height (−0.45**) and yield (−0.39**). Tassel area index was negatively correlated with plant height (−0.63**) and yield (−0.55**), as were number of branches and Leaf Area Index (0.39**). Number of primary branches showed medium correlation with plant height (−0.43**). Test weight correlated negatively with plant height, ear height, yield, leaf area index (LAI) and 1000-kernel weight. Because a number of these traits are highly heritable, these correlations could be used as a basis for indirect selection of special features in maize breeding programs.

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The aim of the research is to reveal the most important influencing factors that lead to consumers’ acceptance of personalised nutrition based on genetic testing. A nationwide representative questionnaire-based consumer survey was carried out involving 500 people in Hungary in 2014. The results show that consumers are divided over the new technology. Only 27.0% of the respondents have a positive attitude toward the new possibility, and they would be glad to use this new service in order to stay healthy. The rate of those who would have a genetic test because they want to follow a diet tailored to their needs is very low (16.0%). Our result suggested that the most important factors in consumer preference on personalised nutrition are positive health message and perceived risk/benefits, gender, and educational level. The most important factors regarding the attitude toward genetic testing are easy usage, benefits, the agreement among experts, and educational level.

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Seven traits of twelve hybrids derived from direct and reciprocal crosses of four parental lines were examined during three years in Hungary. No significant differences were found between the direct and reciprocal crosses for stalk diameter or leaf number over the average of three years in any of the hybrids. Significant differences in the number of primary tassel branches were observed between UDH5 and its reciprocal UDH8, and between UDH6 and its reciprocal UDH11. It was evident in both instances that the degree of heterosis in the reciprocal crosses far exceeded that in the direct ones. A high number of tassel branches was dominant over a low number, so this trait was preferentially inherited in the hybrids. A positive correlation was observed between plant height and main ear attachment height (r = 0.67**). A positive correlation (r = 0.89**) was also found between the length of the main tassel axis above the lowest and above the uppermost side-branch. A medium correlation was observed between the number of primary tassel branches and the plant height (r = −0.42**). The number of primary tassel branches exhibited the highest heterosis. These results can be utilized in practical selection and seed production.

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The role of special corns in human diets is increasing as a result of their favourable nutritional values. Little is known about mineral contents of different red and blue corns, although they may help to inhibit deficiency diseases mainly in the developing countries. During this study, mineral contents (15 elements) of 3 red and 9 blue corn varieties were examined with ICP-OES and ICP-MS. Highest contents of macroelements were as follows: P (3859.5±562.1 mg kg −1 ), K (4325.0±469.5 mg kg −1 ) and Mg (1450.0±104.6 mg kg −1 ) in the variety Black Mexican, S (1555.0±128.6 mg kg −1 ) in Santo Domingo Blue. In case of microelements, iron, zinc and selenium were highlighted. Except one genotype, iron contents were above 30 mg kg −1 . Blaumais, Hopi Turquoise and Hopi Blue contained more than 40 mg kg −1 (41.0–46.3), which were above values published in the literature (10.0 mg kg −1 in average). For zinc, we measured 15.2–31.5 mg kg −1 . Selenium contents (0.1–0.2 mg kg −1 ) were also higher than in the literature (0.08 mg kg −1 ). Plant selection could utilize variability of special element contents in enhancing these phenomena.

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Abstract  

Volatilization of ultramicroamounts of spallogenic products (Mo, Tc, Ru, Re and Os) from the melts of irradiated Ag and Au metals under dynamic vacuum conditions at 10−3–10−2 torr O2 and H2O vapours and their separation in a thermochromatographic column are studied. The influence of the time of sublimation, the gas phase parameters and the materials of the crucible and the column are investigated. Possible reactions and chemical forms of volatile spallogenic products are discussed. Diffusion coefficients are defined for an Ag-melt case. The conditions of Re/Os and Mo/Tc/Ru separation are found. The possibility of using the Ag and Au melts in the ISOL-system is considered.

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Abstract  

Diffusion of the ultramicro amounts of elements, obtained by irradiation with 660 MeV protons in silver, has been studied in molten silver at 1080±20°C. Concentration distribution of the elements has been determined by a fractional layer dissolution method. Diffusion coefficients, the knowledge of which seems to be important for “on-line” isotope production, have been determined by means of relationships obtained from the theoretical evaluation of the processes.

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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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