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  • Author or Editor: Á. Halász x
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Almond [Prunus dulcis (Mill.) D.A. Webb.] is cultivated for its nuts and is one of the oldest domesticated plants. Due to the genetically controlled self-incompatibility system that operates in this species, almond is characterized by great genetic diversity, the estimation of which has benefited from a range of marker techniques, including morphological characteristics, isoenzyme detection and molecular markers. Among the DNA-based molecular markers, simple sequence repeats (SSR) have been used most widely, although analyses have ranged from restriction fragment length polymorphism to the most recent single nucleotide polymorphism detection methods. Molecular markers have also been used to trace specific agronomic traits, e.g. self-(in)compatibility or kernel bitterness. Genetic diversity studies in almond have not revealed a direct relationship between the level of diversity and the origin of the germplasm. This might be explained by the relatively recent occurrence of self-compatibility in almond, which has not yet caused a serious loss of genetic diversity. The markers reviewed will be useful in monitoring and maintaining genetic diversity in almond breeding programmes, while others may permit marker-assisted selection for favourable agronomic traits. The cultivation, breeding and conservation of wild-growing almonds may equally benefit from the genetic diversity studies (especially those applying molecular markers).

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The aim of this study was to adapt MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] colorimetric assay (MCA) (Wang et al., 2010) for determination of lactic acid bacteria cell count. Our study is helpful in developing protocols for measuring the viability of other lactic acid bacteria. We determined the cell concentration range which gives linear regression of CFU (colony forming units) and formazan production. In our experiment three authentic lactic acid bacteria strains were investigated: Lactobacillus rhamnosus VT1, L. plantarum 2142, and L. sakei DSM 2001. As data show beside the strain also the growth medium has influence on the MTT reduction activity, this means that for each special case separate calibration curve has to be prepared. Based on MTT reduction we also developed an improved microtiter plate assay which proved to be reliable for a rapid cell count determination. So our methods are only applicable for estimate cell number with fixed parameters, but under given circumstances they are fast and sensitive methods. With the modified methods we can rapidly measure the dehydrogenase enzyme activity of the lactic acid bacteria cells. With the microplate assay we can measure many conditions and strains at the same time.

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The aim of this study was to develop an accurate, fast and safe routine diagnostic method based on protein studies for differentiating between T. caries and T. controversa at species level. Since import of wheat contaminated with T. controversa is restricted by several countries, differentiation of T. controversa from the more prevalent T. caries is of economic interest. The newly developed method is based on distilled water washing followed by the rupturing of the teliospore walls in PBS extraction medium, and an SDS electrophoresis (10% resolving gel). The electrophoretic pattern showed consistent species-related differences in a 106 kDa polypeptide that appeared in each extract of T. controversa, but was not present in the protein extracts of T. caries. The newly developed method could be of value for the authorities performing routine monitoring of T. controversa as an up-to-date diagnostic assay in wheat shipments.

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Thermogravimetric investigation

Solid-state ion-exchange procedure of Cu2+, Co2+, Ni2+ and Fe2+ ions into montmorillonite

Journal of Thermal Analysis and Calorimetry
Authors: Á. Fudala, J. Halász and I. Kiricsi

Ion-exchange of transition metal ions into montmorillonite was investigated using two different ion-exchange procedures. Performing ion-exchange from aqueous solution of the respective metal ion leads to material possessing measurable BrØnsted acidity, while the solid-state exchange materials show predominantly Lewis acidity.

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Abstract  

The total area of the57Fe Mössbauer spectra of the EuBa2 (Cu0.98 119Sn0.01 57Fe0.01)3O7- superconductor exhibited a highly usual anomalous temperature dependence, i.e. it increased monotonously with increasing temperature between 120 and 300 K. We found also anomalous changes in the57Fe Mössbauer parameters around Tc. These latter changes could be associated with phonon softening and low temperature phase transformation.

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Scientometrics
Authors: J. Jiménez, P. Hunya, M. Bayona and A. Halász

Abstract  

Mexico and Hungary carried out a survey of their national S & T potential in 1985–86, under the framework of the UNESCO International Comparative Study on the Organization and Performance of Research Units (ICSOPRU). A set of questionnaires were administered to heads of research institutions, heads of research units, and core members of research units. Comparison between both S & T systems shows that science is in a more advanced development stage in Hungary than in Mexico. The Hungarian scientific infrastructure is larger than the Mexican one by a factor of four. Also, science as an organized body of researchers is older in Hungary than in Mexico. Science in Hungary is more practically oriented than in Mexico. The S & T system in Hungary has strong links with the productive sector and hance gets substantial support from it. Mexican science, in contrast, is not strongly related to the productive sector, and does not get much financial support from it. Hungarian science is more internationally oriented. Hungarian researchers publish more than Mexican researchers, although a fraction of Mexican units have a publication rate comparable to highly productive Hungarian units. Both S & T systems have many needs in terms of human and material resources for work over the next four to six years. In-depth analysis of available data will shed more light about the S & T potential of both countries.

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The solid-state ion-exchange procedures of zeolites with Cu2+, Ni2+, Fe2+ and Co2+ salts can be resulted in prosperous catalysts for NO decomposition. Reactions taking place in solid-state between four transition metal cholirides and H-ZS-5 zeolite were investigated by means of a derivatograph. The results showed that irreversible consumption of surface -OH groups occurred with simultaneous bonding of the transition metal in the zeolite channel structure.

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