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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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Abstract

Ageing is a common problem in modern societies. Due to sophisticated new methods in medicine, the average life expectancy significantly increased in recent years. 70 is the new 50. The new principles of food intake and processing, more exercise, and less smoking contributed to a health benefits and a longer life span of human kind. Nevertheless, there are the special problems of ageing. Numerous dysfunctions of the body may arise affecting a broad range of organs and the musculoskeletal system. The eye can also be severely affected by ageing. Vision gained more importance recently especially during the COVID-19 pandemic. Elderly people who never used computers before, had to learn computer technology in order to communicate with their family and to accomplish their everyday tasks or pay their bills. Therefore, good near vision has become crucial for elderly people. In this review article the most common ageing problems of the eye, therapies and pathophysiology of ageing processes will be reviewed and discussed. There are physiological problems of ageing and there are ocular pathologies which can be treated efficiently in time to preserve near and far visual acuity.

Open access

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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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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Abstract

Purpose

The aim of this study was to assess longitudinal changes in retinal vessel density in diabetic patients using optical coherence tomography angiography (OCTA) to identify the most sensitive parameter for detecting retinopathy progression.

Methods

Patients with diabetes mellitus were enrolled in this study. Each study subject underwent two imaging sessions, during which three OCTA images of the macular area and three images of the optic nerve head were obtained. The two sessions took place one year apart. The OCTA imaging was performed using an AngioVue device. Superficial vessel density was evaluated in the central 3 mm and parafoveal area, and the nonflow area was measured using the built-in automated AngioAnalytics software of the Optovue system.

Results

This study included 78 eyes of 39 diabetic patients (age: 55.16 ± 13.73 years) with a mean of 7.70 ± 1.07 mmol L−1 HgA1c level at baseline. At the one-year visit, the eyes of the diabetic subjects had significantly lower superficial vessel density in the parafoveal macula compared to corresponding values at baseline (p < 0.05). There was no statistically significant difference between the baseline and one-year results for the other vascular density parameters and the foveal avascular zone (p > 0.05).

Conclusion

At the one-year follow-up, we found that vessel density had decreased in the parafoveal ring in these patients, while there was no significant change in other vascular parameters. This result suggests that superficial parafoveal capillary density is the most sensitive OCTA parameter that can be used as a biomarker for diabetic retinopathy progression. None of the other vascular density parameters nor the foveal avascular zone were able to indicate the subtle changes in retinal microcirculation due to the progression of diabetic microvasculopathy.

Open access

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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The changes of cell surface hydrophilicity in Bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, pH-shock, phosphate- and carbon-limitation.  Although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions.  An observed drop in intracellular GTP and/or ATP may be an element of the signal transduction pathway leading to an increase in surface hydrophilicity in response to environmental stresses.  Attachment of cells to soil particles under salt stress conditions is strongly influenced by the degS/degU two-component system, which thereby provides a mechanism for the bacteria to escape from the hostile environment.

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