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Context. The problem of determining the object-oriented design (OOD) complexity of the open-source software, including Web apps created using the PHP frameworks, is important because nowadays open-source software is growing in popularity and using the PHP frameworks making app development faster. The object of the study is the process of determining the OOD complexity of the open-source Web apps created using the PHP frameworks. The subject of the study is the mathematical models to determine the OOD complexity due to the identification of classes of the open-source Web apps created using the PHP frameworks. Objective. The goal of the work is the build a mathematical model for determining the OOD complexity due to the identification of classes of the open-source Web apps created using the PHP frameworks based on the three-variate Box-Cox normalizing transformation to increase confidence in determining the OOD complexity of these apps. Method. The mathematical model for determining the OOD complexity due to the identification of classes of the open-source Web apps created using the PHP frameworks is constructed in the form of the prediction ellipsoid equation for normalized metrics WMC, DIT, and NOC at the app level. We apply the three-variate Box-Cox transformation for normalizing the above metrics. The maximum likelihood method is used to compute the parameter estimates of the three-variate Box-Cox transformation. Results. A comparison of the constructed model based on the F distribution quantile with the prediction ellipsoid equation based on the Chi-Square distribution quantile has been performed. Conclusions. The mathematical model in the form of the prediction ellipsoid equation for the normalized WMC, DIT, and NOC metrics at the app level to determine the OOD complexity due to the identification of classes of the open-source Web apps created using the PHP frameworks is firstly built based on the three-variate Box-Cox transformation. This model takes into account the correlation between the WMC, DIT, and NOC metrics at the app level. The prospects for further research may include the use of other data sets to confirm or change the prediction ellipsoid equation for determining the OOD complexity due to the identification of classes of the open-source Web apps created using the PHP frameworks. [ABSTRACT FROM AUTHOR]

Abstract  The organization of the lophophore is the main feature used for the identification of phoronid species. The structure of the lophophore and tentacles in seven phoronid species (Phoronis ovalis, P. ijimai, P. hippocrepia, P. svetlanae, P. australis, Phoronopsis harmeri, and Ph. malakhovi) collected in different areas of the World Ocean was studied. Two new patterns of the phoronid lophophore structure were found: “transition to horseshoe-shaped” (as in P. ovalis from Aniva Bay and in P. ijimai from the coast of Iturup Island, Sea of Okhotsk) and “transition to spiral” (in burrowing specimens P. hippocrepia from Aniva Bay, P. svetlanae and Ph. harmeri from Vostok Bay, Sea of Japan). For the first time it was shown that phoronid species with different types of the lophophore structure possess different kinds of tentacles. Thus, five types of phoronid tentacles were identified that vary in the shape of their cross section: rounded, oval, ellipsoid, rectangular, and skittle-shaped. A correlation was found between lophophore organization and the type of tentacles in phoronids. A table of the correlation between body size, lophophore organization, tentacle structure, and mode of life in different phoronid species is proposed. [ABSTRACT FROM AUTHOR]

Abstract Tests of V94.2 gas-turbine units (GTU) of the first PGU-450T plant of the North-West Cogeneration Plant of St. Petersburg are described. The parameters of the GTU and the regular features of their variation are determined in a wide range of operating conditions from idle running to full load. The GTU are characterized by high pressure losses in a cycle, high values of specific power and yield factor, and low concentrations of toxic gases in combustion products at operating modes ranging from 50% load to full load. Quite high efficiencies of the turbomachines are obtained under conditions close to the design ones. The maximum power of 173 MW is attained at a temperature of –10°C and GTU efficiency of 34.5%. [ABSTRACT FROM AUTHOR]

Tests of V94.2 gas-turbine units (GTU) of the first PGU-450T plant of the North-West Cogeneration Plant of St. Petersburg are described. The parameters of the GTU and the regular features of their variation are determined in a wide range of operating conditions from idle running to full load. The GTU are characterized by high pressure losses in a cycle, high values of specific power and yield factor, and low concentrations of toxic gases in combustion products at operating modes ranging from 50% load to full load. Quite high efficiencies of the turbomachines are obtained under conditions close to the design ones. The maximum power of 173 MW is attained at a temperature of –10°C and GTU efficiency of 34.5%. [ABSTRACT FROM AUTHOR]

The ultrastructure of the wall of the main blood vessels of the phoronid Phoronopsis harmeri is described. The walls of the lophophoral and left lateral vessels consist of myoepithelial cells of the coelomic lining (peritoneal cells), a thin basal lamina, and an incomplete endothelial lining. In the head region of the body, the wall of the medial vessel consists of myoepithelial cells of the coelomic lining (peritoneal cells), a basal lamina, and true muscular endothelial cells. The anterior part of the medial vessel functions as the heart. In the anterior part of the body, the medial vessel wall consists of five layers: the external nonmuscular coelothelium, a layer of the extracellular matrix, the internal muscular coelothelium, an internal layer of the extracellular matrix, and an incomplete endothelial lining. The complicated structure of the medial vessel wall may be explained by the superimposition of the lateral mesentery on the ordinary vessel wall. [ABSTRACT FROM AUTHOR]

Abstract Comparative anatomy and embryology provide impressive evidence that the ventral side of all Bilateria (except Chordata) originates from the blastoporal surface, while the mouth and anus develop, respectively, from the anterior and posterior extremities of an elongated blastopore. From the point of view of paleontology, some Vendian multicellular animals represent transitional forms between Radiata and Bilateria. Vendian Bilateria are metameric organisms with a symmetrical or asymmetrical arrangement of segments; they can be considered as bilaterally symmetrical coelenterates crawling on the oral surface. In the recent Cnidaria, homologues of the genes Brachyury, goosecoid and fork head are expressed around the mouth. In the recent Bilateria these genes are expressed along the elongated blastopore and around the mouth and anus. These data corroborate the validity of the idea of amphistomy and the homology between the ventral surface in Bilateria and oral disk in coelenterates. It is supposed that the ancestors of Bilateria were crawling on the oral surface (=ventral side) and gave rise to both Fanerozoic Cnidaria and triploblastic Bilateria. This allows us to suggest the origin of Bilateria from Vendian bilaterally symmetrical coelenterates with numerous metameric pockets of the gastral cavity. Such ancestors gave rise to both Cnidaria and Bilateria. Apparently the primary Bilateria were complicated organisms having a coelom and segmentation, which allows us to explain the great diversity of highly organized organisms (arthropods, mollusks, and others) in the Cambrian era. An idea is proposed that Ctenophora are the only group of recent Eumetazoa that retain primary axial symmetry. [ABSTRACT FROM AUTHOR]

Four types of blood capillaries of the phoronid Phoronopsis harmeri are described. These are capillaries of the tentacles, of the body, of the stomach plexus, and of the vasoperitoneal tissue. The wall of capillary consists of cells of the coelomic lining, a layer of extracellular matrix, and separate endothelial cells. Myoepithelial coelomic cells of tentacle capillaries contain cross-striated fibers. In capillaries of the body and the stomach plexus, the myofilaments are smooth. In the cells of the wall of vasoperitoneal tissue capillaries, myofilaments are lacking. The cells of the vessel wall of the tentacles, the body, and the vasoperitoneal tissue bear a single cilium. The cells of capillaries of the stomach plexus lack a cilium. The ultrastructure of erythrocytes and amebocytes is described. In the cytoplasm of erythrocytes, there is a basal body. It is assumed that erythrocytes originated from the ciliary cells of the wall of the blood vessels. [ABSTRACT FROM AUTHOR]

Power characteristics of the V94.2 gas-turbine unit operating at a PGU 470-T cogeneration plant are presented. The dependences are plotted with the use of experimental data obtained during heat tests of the gas-turbine unit. [ABSTRACT FROM AUTHOR]