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This study examined the activities of aspartate aminotransferase (ASAT), alanine aminotrans-ferase (ALAT), alkaline phosphatase (ALP), acid phosphatase (ACP), albumin (Alb), total protein (TP), creatin-phosphokinase (CPK), total lipid (TL), calcium (Ca) in the plasma of 304 dairy Holstein breed cows and their calves. The cows were held in an intensive farm breeding premises. Their meal consisted of ordinary alfalfa, silage, hay and concentrates with energy and protein supplements. The Student t-test showed significant difference (P < 0.05) in mean of the ASAT, ALAT, ALP, ACP, Alb, TP, TL, Ca between cows and calves of the breed. Mean values of the ASAT, ALAT, Alb, TP, TL and Ca was higher in cow group than in calves group (P < 0.05), while ALP and ACP was lower in cow in comparison to the calves group (P < 0.05).

ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗ ΣΤΑ ΕΛΛΗΝΙΚΑ, Avian embryos have been gaining an increasing scientific interest as a valuable model system for the experimental cancer research that could contribute to a significant reduction of the number of laboratory animals. In the present study, the liver lesions induced by N-nitrosodimethylamine and N-nitrosodiethylamine in 15I line, White Leghorn embryos were identified and studied by routine histopathological method s. Foci of altered hepatocytes with basophilic and eosinophilic phenotype, well known as preneoplastic alterations were identified in the avian embryonal livers after in ovo exposure to both N-nitroso compounds. These studies were further extended by histopathological, haematological and biochemical examinations on the effects of N-nitrosodimethylamine in chickens hatched from carcinogen-inoculated eggs. In addition to the preneoplastic lesions observed in the avian livers, proliferations of oval and hepatocellular carcinoma cells, with clearly expressed signs of malignancy were found. The in ovo application of the chemical carcinogen was found to affect both hematological and blood biochemistry parameters measured in experimental birds. The established conditions such as thrombocytopenia and increased levels of liver enzymes, as an essential part of the paraneoplastic syndrome, were associated with the process of hepatocarcinogenesis. The results of this study confirm the preneoplastic nature of the focal lesions in embryonal avian liver and their progression to liver neoplastic alterations after a single in ovo application of known hepatocarcinogens. Moreover, the results indicate that 15I line, White Leghorn embryos are anew, valuable in ovo model for studies on hepatocarcinogenicity of chemical compounds and underline the importance of research on the development of different avian models of carcinogenicity.

We present new results towards the construction of the most general black hole solutions in four-dimensional Fayet-Iliopoulos gauged supergravities. In these theories black holes can be asymptotically AdS and have arbitrary mass, angular momentum, electric and magnetic charges and NUT charge. Furthermore, a wide range of horizon topologies is allowed (compact and noncompact) and the complex scalar fields have a nontrivial radial and angular profile. We construct a large class of solutions in the simplest single scalar model with prepotential $F = -i X^0 X^1$ and discuss their thermodynamics. Moreover, various approaches and calculational tools for facing this problem with more general prepotentials are presented., Comment: 37 pages, 1 figure

We determine the thermodynamic properties of a class of spherically symmetric and static black holes in AdS4 with magnetic charges and scalar hair. These black holes are solutions in 4d N=2 gauged supergravity that can arise from eleven-dimensional supergravity compactified on S^7. At zero temperature, they preserve supersymmetry and hence are stable. At non-zero temperatures, we explore in detail the canonical ensemble and stability of solutions and find a first order phase transition between small and large hairy black holes. The transition emerges as a liquid-gas phase transition in the dual three-dimensional field theory on R x S^2 with magnetic flux through S^2., 5 pages, v2: misprints corrected and references added, published version

This thesis is devoted to a study of supersymmetry preserving background solutions of N=2 supergravity in 4 dimensions. These models include arbitrary electric gaugings in the vector- and hypermultiplet sectors introduced in the beginning of the thesis. The main contents are divided into three major parts. In part 1 we consider vacua that can be fully analyzed by requiring preserved supersymmetry. We determine and analyze maximally supersymmetric configurations, preserving eight supercharges. We present several examples of such solutions and connect some of them to vacuum solutions of flux compactifications in string theory. We also provide a consistent truncation of the gauged theory based on integrating out massive supermultiplets of the gauged theory. The second part is devoted to the topic of supersymmetric black holes. These can be asymptotically flat or asymptotically AdS, and we analyze both cases in detail. We construct BPS black hole solutions in Minkowski space with charged hypermultiplets. We find solutions with vanishing scalar hair that resemble already known black holes, while the genuinely new solutions with hair that we find contain ghost modes. We also elaborate further on the static supersymmetric AdS black holes found in arXiv:0911.4926, investigating thoroughly the BPS constraints for spherical symmetry in N = 2 gauged supergravity. We find Killing spinors that preserve two of the original eight supercharges and investigate the conditions for genuine black holes free of naked singularities. The existence of a horizon is intimately related with the requirement that the scalars are not constant, but given in terms of harmonic functions in analogy to the attractor flow in ungauged supergravity. The third major topic of this thesis is BPS bounds, where we discuss asymptotically Minkowski and AdS solutions in full generality. We concentrate on asymptotically anti-de Sitter (AdS) spacetimes, and find that there exist two disconnected BPS ground states of the theory, depending on the presence of magnetic charge. Each of these ground states comes with a different superalgebra and a different BPS bound, which we derive. As a byproduct, we also demonstrate how the supersymmetry algebra has a built-in holographic renormalization method to define finite conserved charges. We derive the general form of the charges for all asymptotically flat, anti-de Sitter, and magnetic anti-de Sitter spacetimes. Some particular black hole examples from part 2 are considered to explicitly demonstrate how AdS and mAdS masses differ when solutions with non-trivial scalar profiles are considered

We focus on black branes and toroidal black holes in N = 2 gauged supergravities that asymptote to AdS4, and derive formulas for the mass and central charge densities. We derive the corresponding BPS bound from the superalgebra of the asymptotic vacuum and illustrate our procedure with explicit examples of genuine black brane solutions with non-trivial scalars.

We determine the BPS bounds in minimal gauged supergravity in four spacetime dimensions. We concentrate on asymptotically anti-de Sitter (AdS) spacetimes, and find that there exist two disconnected BPS ground states of the theory, depending on the presence of magnetic charge. Each of these ground states comes with a different superalgebra and a different BPS bound, which we derive. As a byproduct, we also demonstrate how the supersymmetry algebra has a built-in holographic renormalization method to define finite conserved charges., Comment: 23 pages; v2 typos corrected, published version; v3 typos in Eqs. (3.6) and (3.31) corrected

We determine the BPS bounds in minimal gauged supergravity in four space- time dimensions. We concentrate on asymptotically anti-de Sitter (AdS) spacetimes, and find that there exist two disconnected BPS ground states of the theory, depending on the presence of magnetic charge. Each of these ground states comes with a different superal-gebra and a different BPS bound, which we derive. As a byproduct, we also demonstrate how the supersymmetry algebra has a built-in holographic renormalization method to define finite conserved charges.

We determine and analyze maximally supersymmetric configurations in four-dimensional gauged N = 2 supergravity, preserving eight supercharges. These models include arbitrary electric gaugings in the vector- and hypermultiplet sectors. We present several examples of such solutions and connect some of them to vacuum solutions of flux compactifications in string theory.

A scenario for stabilization of axionic moduli fields in the context of type IIB Calabi-Yau flux compactifications is discussed in detail. We consider the case of a Calabi-Yau orientifold with h1,1−≠0 which allows for the presence of B2 and C2-moduli. In an attempt to generalize the KKLT and the Large Volume Scenario, we show that these axions can also be stabilized - some already at tree level, and others when we include perturbative α'-corrections to the Kähler potential K and nonperturbative D3-instanton contributions to the superpotential W. At last, we comment on the possible influence of worldsheet instantons on the process of moduli stabilization.

London

March Issue

The study was performed on testes, obtained from 14 vipers (Vipera ammodytes), inhabiting various regions of Bulgaria, collected during the four seasons of the period 1996-1999 inclusive. The weight and the macrometric parameters of testes were measured. The outer diameter of seminiferous tubules and season-related microstructural features were determined via light microscopy. Data from weight, metric and micrometric measurements were statistically processed. Their analysis showed that from winter to the end of spring (when the breding period of vipers in Bulgaria occurs), the weight of testes increased more than thrice, the diameter of seminiferous tubules - more than twice and afterwards the values of both parameters decreased gradually and reached the highest values for the winter season by the end of the autumn. The seasonal variations in both weight and diameter correlated with the histological status of testes. The involution processes within seminiferous tubules, starting by the beginning of winter, were still active also in the middle or end of spring, when vipers were ready again for another reproductive period.

Universitat de Valencia; Papers Transitio, Unitat d'Investigatio Formacions Socials en Transicio n°2, 25p.

Bulgarian Academy of Sciences

Sofia

We construct and analyze BPS black hole solutions in gauged N=2, D=4 supergravity with charged hypermultiplets. A class of solutions can be found through spontaneous symmetry breaking in vacua that preserve maximal supersymmetry. The resulting black holes do not carry any hair for the scalars. We demonstrate this with explicit examples of both asymptotically flat and anti-de Sitter black holes. Next, we analyze the BPS conditions for asymptotically flat black holes with scalar hair and spherical or axial symmetry. We find solutions only in cases when the metric contains ripples and the vector multiplet scalars become ghost-like. We give explicit examples that can be analyzed numerically. Finally, we comment on a way to circumvent the ghost-problem by introducing also fermionic hair., 40 pages, 2 figures; v2 references added; v3 minor changes, published version