Volumetric studies of mica spatial distribution inside samples of Westerly and Czech granites (Mrakotin, Liberec, and Brno syenite) were performed using a neutron tomography method. A significant difference in the neutron attenuation coefficients of mica and other rock-forming minerals of the granites studied yielded a large neutron radiography contrast and, as a result, allowed us to perform a detailed analysis of three-dimension structural data based on the neutron tomography reconstruction procedure. The morphology and spatial distribution of the mica phase within studied granites were obtained. Tomography data were compared to results provided by other experimental methods commonly used in rock mechanics research such as optical and electron microscopy, as well as ultrasonic shear-wave measurements. The benefits and limitations for application of the neutron tomography method for studies of granite like rocks are discussed.
The presence of terminal carbohydrate residues in Enteromyxum leei (Diamant, Lom et Dyková, 1994) Palenzuela, Redondo et Álvarez-Pellitero, 2002 stages in gilthead seabream intestines was studied at light microscopy (LM) and transmission electron microscopy (TEM) level using lectin histochemical techniques. Abundant mannose and/or glucose residues were demonstrated by the intense staining caused by binding of biotinylated concanavalin A (Con A), at both LM and TEM. A clear positivity was also obtained with Ulex europaeus (UEA I) agglutinin specific for fucose residues. Both lectins stained E. leei proliferative and sporogonic stages, though glycan patterns varied between these developmental stages. Wheat germ agglutinin (WGA) and Bandeiraea simplicifolia lectin I (BSL I) recognised only structures in the sporogonic stages. Faint labelling occurred with Glycine max (SBA) lectin. No staining was obtained with Sambucus nigra (SNA) agglutinin. The TEM studies demonstrated a restricted presence of N‑acetyl-D-galactosamine and α-D-galactose, whereas glucose/mannose and fucose, the dominant structures, were also present at the parasite membranes and host-parasite interface, suggesting a role in host-parasite interaction.
In the course of more than one hundred years of its existence, the sound recording became not only an important tool of ethnomusicological research, but also the factor of influence for the folk music. Forms of this relationship change together with the changes of the technical form of recording and reproduction and also with the changes of the attitude of society to these technologies. Roughly stated, there are three basic forms of relationship of folk music and sound recording. In the initial phase the sound recording - first on wax rolls - had been used for archivation of acoustic manifestations of folk music. Relatively early, however, folk music had been also spread and popularized by this means. This brought about also the influence of sound recording on mutual influencing of specific cultures and regions. The more and more accessible technologies of sound recording causes changes of the processes by which music is being passed down and taught. In the last decades, the sound recording had become also the means of music creation, a fact that manifests itself especially in various genres of contemporary electronic dance music.
The long-term impact of elevated concentration of CO2 on assimilation activity of sun-exposed (E) versus shaded (S) foliage was investigated in a Norway spruce stand [Picea abies (L.) Karst, age 14 years] after three years of cultivation in two domes with adjustable windows (DAW). One DAW was supplied with ambient air [AC, ca. 350 µmol(CO2) mol-1) and the second with elevated CO2 concentration [EC = AC plus 350 µmol(CO2) mol-1]. The pronounced vertical profile of the photosynthetic photon flux density (PPFD) led to the typical differentiation of the photosynthetic apparatus between the shaded and sun needles. Namely, photon-saturated values of maximal net photosynthetic rate (PNmax) and apparent quantum yield (α) were significantly higher/lower for E-needles as compared with the S-ones. The prolonged exposure to EC was responsible for the apparent assimilatory activity stimulation observed mainly in deeply shaded needles. The degree of this stimulation decreases in the order: S-needles dense part > S-needles sparse part > E-needles dense part > E-needles sparse part. In exposed needles some signals on a manifestation of the acclimation depression of the photosynthetic activity were found. The long-term effect of EC was responsible for the decrease of nitrogen content of needles and for its smoother gradient between E- and S-needles. The obtained results indicate that the E- and S-foliage respond differently to the long-term impact of EC. and M. V. Marek ... [et al.].
The paper deals with problems concerning power gyroscopes for stabilization of vibro-izolation system. Two variants of gyro support with air drive were designed, namely with gas bearings and precision rolling bearings. Precession frame of the gyro is supported in aerostatic journal bearings to achieve minimum passive resistance. Some special phenomena, such as pneumatic instalibity, were found in some test regimes both at aerostatic thrust bearing of gyro support and aerostatic journal bearings of the frame support. However, with air inlet pressure level limited to value required for proper function of bearings, no instability was encountered.
In 1986 P. Šeba in the classic paper considered one-dimensional pseudo-Hamiltonians containing the first derivative of the Dirac delta function. Although the paper contained some inaccuracy, it was one of the starting points in approximating one-dimension self-adjoint couplings. In the present paper we develop the above results to the case of quantum systems with complex geometry.