The Ability of Cyanobacterial Cells to Restore UV-B Radiation Induced Damage to Photosystem II is Influenced by Photolyase Dependent DNA Repair

Damage of DNA and Photosystem-II are among the most significant effects of UV-B irradiation in photosynthetic organisms. Both damaged DNA and Photosystem-II can be repaired, which represent important defense mechanisms against detrimental UV-B effects. Correlation of Photosystem-II damage and repair with the concurrent DNA damage and repair was investigated in the cyanobacterium Synechocystis PCC6803 using its wild type and a photolyase deficient mutant, which is unable to repair UV-B induced DNA damages. A significant amount of damaged DNA accumulated during UV-B exposure in the photolyase mutant concomitant with decreased Photosystem-II activity and D1 protein amount. The transcript level of psbA3, which is a UV-responsive copy of the psbA gene family encoding the D1 subunit of the Photosystem-II reaction center, is also decreased in the photolyase mutant. The wild-type cells, however, did not accumulate damaged DNA during UV-B exposure, suffered smaller losses of Photosystem-II activity and D1 protein, and maintained higher level of psbA3 transcripts than the photolyase mutant. It is concluded that the repair capacity of Photosystem-II depends on the ability of cells to repair UV-B-damaged DNA through maintaining the transcription of genes, which are essential for protein synthesis-dependent repair of the Photosystem-II reaction center

Inversion-Based Fourier Transform as a New Tool for Noise Rejection

In this study, a new inversion method is presented for performing two-dimensional (2D) Fourier transform. The discretization of the continuous Fourier spectra is given by a series expansion with the scaled Hermite functions as square-integrable set of basis functions. The expansion coefficients are determined by solving an overdetermined inverse problem. In order to define a quick algorithm in calculating the Jacobian matrix of the problem, the special feature that the Hermite functions are eigenfunctions of the Fourier transformation is used. In the field of inverse problem theory, there are numerous procedures for noise rejection, so if the Fourier transformation is formulated as an inverse problem, these tools can be used to reduce the noise sensitivity. It was demonstrated in many case studies that the use of Cauchy-Steiner weights could increase the noise rejection capability of geophysical inversion methods. Following this idea, the two-dimensional Fourier transform is formulated as an iteratively reweighted least squares (IRLS) problem using Cauchy-Steiner weights. The new procedure is numerically tested using synthetic data

Módszerfejlesztés mélyfúrási geofizikai adatok integrált intervallum-inverziójára földtani szerkezetek morfológiájának meghatározása céljából = New method for the determination of morphology of the geological structures using integrated interval inversion of well log data

A mélyfúrási geofizikai adatok inverziójának irodalmi feldolgozását ill. a mélységpontonkénti- és az intervalluminverziós algoritmusok fejlesztésében elért legfontosabb nemzetközi és hazai eredmények áttekintését az egyik közreműködő kutató elvégezte és 2005-ben megvédett PhD értekezésében közölte. Az eredetileg egyetlen fúrásban mért adatok értelmezésére kidolgozott intervallum inverziós módszert továbbfejlesztettük, ezáltal lehetővé vált több fúrás adatainak együttes inverziója, mely az ismeretlen petrofizkai paramétereken túl a réteghatárok laterális (2-D) elhelyezkedését is szimultán módon meghatározza. Az optimalizáció oldaláról modern, véletlen-keresésen alapuló globális szélsőérték-kereső eljárást (Simulated Annealing) alkalmaztunk, emellett a valós számábrázolású Genetikus Algoritmust is bevontuk vizsgálataink körébe. Az utolsó lépésben lineáris módszerrel kiegészítve (a kovariancia mátrix megadásával) lehetővé vált a becsült paraméterek hibájának meghatározása. Összefoglalásul megállapíthatjuk, hogy a tesztelési eredmények alapján az új módszer alkalmazható terepi adatok inverziójára. Az eljárást alkalmazva végül egy valós hazai CH-tárolón mért adatrendszert dolgoztunk fel. A 2D közelítésben tárgyalt CH-tároló morfológiájára kapott eredmény meggyőzően igazolta az algoritmus gyakorlati használhatóságát. | Most important domestic and international results accomplished by the review of relevant scientific literature and development of local (point-by-point) and interval inversion algorithms were outlined and published in a PhD thesis defended by a researcher participating in the project in 2005. The interval inversion method originally developed for the interpretation of single-well data was further developed by us for supporting the joint inversion of multi-well data giving a simultaneous estimate for petrophysical parameters and lateral (2D) position of layer-boundaries. As for the part of optimization, a modern global optimization method called Simulated Annealing based on random optimum seeking technique was used. A Genetic Algorithm as a float-encoded implementation was applied in the research work, too. The determination of model estimation error was feasible by using a linear step (by specifying the covariance matrix) at the end of the inversion procedure. In conclusion, we can state from the test results that the new method is applicable to the inversion of field data. As an application, we processed a well-logging data set, which was measured in a domestic hydrocarbon field. The result obtained for the morphology of the hydrocarbon reservoir as a 2D approximation proved to be convincing in practical usability

Statistical Analysis of the Hydrological and Hydrometeorological Characteristics of the Upper Tisza Basin

Tisza is the largest water base in the eastern part of Szabolcs-Szatmár-Bereg County, in north-eastern Hungary, and its indirect use is mainly associated with agriculture. Our work investigates the hypothesis that decrease in water levels and water discharges of the Upper Tisza in recent decades, together with the incision of the riverbed and the precipitation falling in the area, have an impact on the groundwater level of the Szatmár-Bereg Plain. In our study, data from three water gauges located between the settlements of Tiszaújlak and Vásárosnamény and data from groundwater level monitoring wells (MW) and Hydrometeorological (HMS) stations on the Szatmár-Bereg Plain were compared using statistical methods in Past 4.11 software. The aim of the current study was to identify the strategic steps that need to be taken by the organisations responsible for water management in the Upper Tisza basin in the light of the changes in hydrological, hydrometeorological, and meteorological factors. To ensure that the region has sufficient water supplies for the next decade, appropriate water management and agricultural strategies could be the solution