Annual Daylight Condition in Bratislava

To compute energy demand based on the reference years hourly averages of external variables are often generated in the smooth form. On the other hand, daylight should be evaluated in a shorter interval because human eyes perceive light in the moment of its occurrence. This study shows alternative to the description of annual daylight conditions based on statistic characteristics mean and median to create Daylight Standard Reference Year for Bratislava. Both methods are presented as contribution to the development of daylighting engineering. Authors are interested in lighting engineering to ensure satisfactory luminous environment at workplaces and in buildings for housing and recreation. Good daylighting in interiors is also related to the reduction of electricity consumption for lighting. This paper presents method for generation of daylight standard reference year DSRY based on one minute data measured at CIE IDMP stations. This reference year can be applied for evaluation of daylighting in the specific locality.

A new species of Casmaria H. Adams & A. Adams, 1853 (Gastropoda, Cassidae) from the Philippines identified by molecular data

The genus Casmaria H. Adams & A. Adams, 1853 (family Cassidae) is widespread in the tropical Indo-Pacific and has been documented from some Atlantic localities as well. Two Casmaria species, C. erinaceus (Linnaeus, 1758) and C. ponderosa (Gmelin, 1791), are common in Indo-Pacific shallow-water sandy bottom communities and are characterized by high morphological variability; both species encompass multiple, often sympatric forms of uncertain status. In the present study we carry out a phylogenetic analysis of some Philippine Casmaria morphs and demonstrate that one of the distinctive morphs earlier assigned to Casmaria ponderosa is in fact a different species, which we describe as Casmaria boblehmani sp. nov. The smooth form of Casmaria ponderosa, C. ponderosa ponderosa, and the solid nodulose form, widely called “form nodulosa” despite being strikingly different in shell morphology, are shown to be conspecific. Studied specimens of these two morphs even from different localities share the same haplotype of the CO1 gene. In light of these new data on the morphological variability of Casmaria species, we discuss criteria of species delimitation in the genus Casmaria and possible affinities of Casmaria boblehmani sp. nov. within the genus.

Microhardness and microstructure of deciduous enamel with different types of amelogenesis imperfecta

Amelogenesis imperfecta (AI) is an inherited tooth disorder with widely varying phenotypes. The aim of this study was to determine the microhardness and microstructure characteristics of the enamel in AI teeth. The AI phenotypes examined were hypoplastic (pitted and smooth form), hypomaturated, and hypocalcified. Six AI patients were diagnosed according to clinical characteristics. The microhardness of the enamel was measured on axial cuts of AI teeth acquired from the patients. The measurements were done on several sites from the enamel surface towards the dentine-enamel junction using the Vickers scale. Values of microhardness were compared to corresponding control teeth. The microstructure of AI enamel types was evaluated using scanning electron microscopy. The values of microhardness in pitted hypoplastic AI samples were, on average, lower compared to the control enamel and dropped markedly towards the dentine-enamel junction. The smooth hypoplastic enamel was not only extremely thin but also much softer than control enamel. The values for hypomaturated AI fluctuated, but the palatal sites were markedly softer than in the control tooth. Hypocalcified enamel was the softest, with values resembling those of dentin. Microstructural changes varied from altered orientation of enamel prisms in pitted hypoplastic AI to lack of normal prismatic structure and severe porosity in hypocalcified AI. The present results suggest different microhardness profiles and microstructures in each phenotype. Variations among phenotypes are expected with larger case selection in this genetically heterogeneous disease.

Analysis of the Role of recA in Phenotypic Switching of Pseudomonas tolaasii

ABSTRACT Switching between the pathogenic smooth (1116S) and nonpathogenic rough (1116R) forms of Pseudomonas tolaasii occurs due to the reversible duplication of a 661-bp element within thepheN locus. Disruption of the chromosomal recAlocus of 1116S and 1116R produced strains 1116SrecAand 1116RrecA, respectively, which showed typical loss of UV resistance. Switching from the smooth to the rough form was virtually eliminated in the 1116SrecA strain, whereas the extent of switching from the rough to the smooth form was almost identical in 1116R and 1116RrecA. It is concluded that phenotypic switching from 1116S to 1116R is recAdependent whereas that from 1116R to 1116S is recAindependent.