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This paper presents the results of soil research in Austrian pine (Pinus nigra Arn.) forest communities in the Višegrad area, carried out to determine the basic soil characteristics and eco-production potential of forest habitats as an important basis and framework for the successful management of these forests on the principles of sustainable development. Austrian pine forests in this region are an important and ecologically valuable community. The complexity of the geological structure and relief dynamics are dominant environmental factors that condition the expressed variability of soils in the study area. Forest communities of Austrian pine are formed on the peridotites and serpentinites, eutric ranker (haplic leptosol), eutric cambisol (haplic cambisols) and pseudogley (haplic planosol), dense granular and marl limestones calcomelanosol (mollic leptosol), rendzina (rendzic leptosol) and calcocambisol (leptic cambisol). The productivity of these soils is highly correlated with depth and texture composition, and the impact of these factors is linked with soil type, climate and other site conditions. In the research area, soil types with low production potential such as rankers, rendzinas, limestone and dolomite calcomelanosol are dominant. Deeper variants of eutric cambisol, pseudogley and calcocambisol can be classified as soils with moderate to high production potential. [ABSTRACT FROM AUTHOR]

We studied a model of semi-directed percolation on finite strips of the square and triangular lattices. Using the transfer-matrix method, combined with phenomenological renormalization group approach, we obtain good numerical estimates for critical probabilities and correlation lengths critical exponents. Our results confirm the conjecture that semi-directed percolation belongs to the universality class of the usual fully-directed percolation model. [ABSTRACT FROM AUTHOR]

We studied distribution of zeros of the partition function of the ferromagnetic Ising model near the Yang-Lee edge on a family of Sierpinski gasket lattices whose members are labeled by an integer b (2 < b < oo). The obtained exact results on the first seven members of this family show that, for b 4, associated correlation length diverges more slowly than any power law when distance Sh from the edge tends to zero, IYL ∼ exp [ln(b)(8h) ln(λo)] ln(λ0)], λo being a decreasing function of b. We suggest a possible scenario for the emergence of the usual power-law behavior in the limit of very large b when fractal lattices become almost compact. [ABSTRACT FROM AUTHOR]

Backgraund/Aim. Gene p53, or "cell genome keeper", has a preventive effect on the occurrence of genetic aberrations and prevents abnormal expansion of (tumor) cells. In gastric cancer cells in most cases we register high expression of mutated p53 gene, which correlates with prognosis and specific clinical-pathological characteristics of gastric cancer. Methods. Using the imunohistochemical method we determined the level of expression of p53 protein in 62 gastric cancers and 30 precancerous conditions (intestinal metaplasia of the stomach). We analyzed the relationship of the level of p53 expression and clinical pathological characteristics of gastric cancer. Results. Expression of p53 was positive in 42 (67.7%) tumor cases and in 7 (14.3%) cases of intestinal metaplasia. Expression of P53 and stomach cancer were in direct correlation (p = 0.000). Sensitivity for p53 in stomach cancer cases was 67.7% (42/62), and specifility was 76.7% (23/30). Expression of mutated p53 protein was in direct correlation with the invasion of lymph nodes (p = 0.034) and with invasion of blood vessels by carcinoma cells (p = 0.042). Conclusion. There is a direct correlation between p53 expression and gastric cancer and it indicates the ability of carcinoma cells to invade blood vessels. [ABSTRACT FROM AUTHOR]

Abstract: We studied distribution of zeros of the partition function of ferromagnetic Ising model near the Yang–Lee edge on two self-similar structures. We have shown that the nature of associated critical behavior crucially depends on the local lattice structure: If the sites of higher coordination number make an infinite connected cluster then we find an usual power-law behavior, while a logarithmic divergence of the correlation length develops near the edge in the case that these sites make only finite islands. We reveal also a close connection between Yang–Lee edge critical behavior and critical behavior of a simple zero-field Gaussian model on the same structures. [Copyright &y& Elsevier]

By using transfer-matrix method we compute survival probabilities for the directed percolation problem on strips of a square lattice, and get very precise estimates of their Yang-Lee zeros lying closest to the real axis in the complex plane of occupation probability. This allows us to get accurate values for transverse-size critical exponent and percolation threshold. [ABSTRACT FROM AUTHOR]

We present a numerical analysis of spanning avalanches in a two-dimensional (2D) nonequilibrium zero-temperature random field Ising model. Finite-size scaling analysis, performed for distribution of the average number of spanning avalanches per single run, spanning avalanche size distribution, average size of spanning avalanche, and contribution of spanning avalanches to magnetization jump, is augmented by analysis of spanning field (i.e., field triggering spanning avalanche), which enabled us to collapse averaged magnetization curves below critical disorder. Our study, based on extensive simulations of sufficiently large systems, reveals the dominant role of subcritical 2D-spanning avalanches in model behavior below and at the critical disorder. Other types of avalanches influence finite systems, but their contribution for large systems remains small or vanish. [ABSTRACT FROM AUTHOR]

We present in detail the scaling analysis and data collapse of avalanche distributions and joint distributions that characterize the recently evidenced critical behavior of the two-dimensional nonequilibrium zero-temperature random field Ising model. The distributions are collected in extensive simulations of systems with linear sizes up to L = 131072. [ABSTRACT FROM AUTHOR]

Non-Hodgkin lymphomas (NHL) often show up in an extranodal pattern, especially in the head and neck. Intraoral locations are much less frequent, particularly when they are single. This, in turn, can lead to a prolonged diagnosis and even to inadequate treatment. Different patients with initial extranodal location of NHL which were not previously diagnosed and in which it was manifested only intraoraly are presented in this paper. These cases are presented together with the additional examinations used for the early diagnosis and with the corresponding clinical pictures, as well as with the overview of other cases from the available literature. [ABSTRACT FROM AUTHOR]

After the excavation of the canals of the main canal network (MCN) of the Danube-Tisza-Danube (DTD) hydro system, specific technological schemes were used to form deposited materials. In 1958 an experiment with forest plantings was set up on the deposols of the Odžaci-Sombor Canal. Its purpose was the protection and reclamation of the newly-formed dikes. The main aim of this paper is to point to the speed of the process of reclamation and changes in soil properties in the course of a 54-year-long experiment, on the basis of a years-long study of the experimental area. [ABSTRACT FROM AUTHOR]

Heavy metals are the substances that indicate environmental pollution. The plants polluted with heavy metals may endanger natural environment and cause health problems in humans. In our multidisciplinary research of the concentrations of pollutants in forest ecosystems and natural environment in Belgrade, we examined the contents of heavy metals essential for plants but harmful in greater concentrations on a long-term basis. The fact that heavy metals manganese and iron are accumulated in plants to the greatest extent focused our work on determination of the level of concentrations of Mn and Fe in the vegetative parts of 8 plant types on three locations on the Avala Mountain and one location in the centre of the city of Belgrade. The analyses of heavy metals contents in plants were performed by the method of flame atomic absorption spectrophotometry. The examination of the existence of important differences between the average values was performed by implementation of Duncans test for the level of significance of 95%. The current contents of heavy metals in plants in the area of the protected natural resource Avala do not represent danger that would presently cause notable damage to forests but show the tendency of the increase of concentrations. Therefore, this issue should be constantly monitored. [ABSTRACT FROM AUTHOR]