The sound wave displacement-based ultrasonic meter dependence on various atmospheric factors

The dependence of speed of ultrasound in air on various climatic factors operating in the atmosphere has a significant impact on the accuracy of the ultrasonic flow measurement method. The article examines how to analyse, calculate and form mathematical formulas for air speed dependencies on all foreseen atmospheric factors that can affect the accuracy and results of measurements. The results obtained will be used for creating a mathematical model in MATLAB environment. The examination of a great number of sources suggests that a mathematical model of the speed of sound evaluating various influencing factors in a wide range has not been created until now. The article provides a partial analysis on this issue that would be applicable only for a partial application of the model used for an acoustic impulse mete

The sound wave displacement-based ultrasonic meter dependence on various atmospheric factors

The dependence of speed of ultrasound in air on various climatic factors operating in the atmosphere has a significant impact on the accuracy of the ultrasonic flow measurement method. The article examines how to analyse, calculate and form mathematical formulas for air speed dependencies on all foreseen atmospheric factors that can affect the accuracy and results of measurements. The results obtained will be used for creating a mathematical model in MATLAB environment. The examination of a great number of sources suggests that a mathematical model of the speed of sound evaluating various influencing factors in a wide range has not been created until now. The article provides a partial analysis on this issue that would be applicable only for a partial application of the model used for an acoustic impulse mete

Formalization of the observations of the sea level variations using XML data schemas and scalable vector graphics format

XML (Extended Markup Language) Data Schemas as the format for information exchange in graphical SVG (Scalable Vector Graphics) format is presented in the paper. SVG file format is a language for two-dimensional graphics and is based on XML. It is suggested to apply it as the advanced version of previous data exchange format TGINEX (Tide Gauge Independent Exchange Format), which contains the plain ASCII data. SVG graphics are formatted from the observations of sea level observations by the tide gauges. As an example, the formalization of data is shown on the base of the sea level observing station KLPD, which is a part of the European Sea Level Service network. XML Data Schemas, in addition, adds header’s information about the marine measurements' site, sensors and any additional necessary information. The correct header formation and the advantages of such data exchange format are analysed. Header is important for exchange between different sites from different countries as so it would be information standartization. Visual appearance of the SVG file, the source, headers and formation of the file in script are described in this paper als

Formalization of the observations of the sea level variations using XML data schemas and scalable vector graphics format

XML (Extended Markup Language) Data Schemas as the format for information exchange in graphical SVG (Scalable Vector Graphics) format is presented in the paper. SVG file format is a language for two-dimensional graphics and is based on XML. It is suggested to apply it as the advanced version of previous data exchange format TGINEX (Tide Gauge Independent Exchange Format), which contains the plain ASCII data. SVG graphics are formatted from the observations of sea level observations by the tide gauges. As an example, the formalization of data is shown on the base of the sea level observing station KLPD, which is a part of the European Sea Level Service network. XML Data Schemas, in addition, adds header’s information about the marine measurements' site, sensors and any additional necessary information. The correct header formation and the advantages of such data exchange format are analysed. Header is important for exchange between different sites from different countries as so it would be information standartization. Visual appearance of the SVG file, the source, headers and formation of the file in script are described in this paper als

Linearly polarized photoluminescence of InGaN quantum disks embedded in GaN nanorods

We have investigated the emission from InGaN/GaN quantum disks grown on the tip of GaN nanorods. The emission at 3.21 eV from the InGaN quantum disk doesn't show a Stark shift, and it is linearly polarized when excited perpendicular to the growth direction. The degree of linear polarization is about 39.3% due to the anisotropy of the nanostructures. In order to characterize a single nanostructure, the quantum disks were dispersed on a SiO2 substrate patterned with a metal reference grid. By rotating the excitation polarization angle from parallel to perpendicular relative to the nanorods, the variation of overall PL for the 3.21 eV peak was recorded and it clearly showed the degree of linear polarization (DLP) of 51.5%

Dynamic microtubules produce an asymmetric E-cadherin-Bazooka complex to maintain segment boundaries.

Distributing junctional components around the cell periphery is key for epithelial tissue morphogenesis and homeostasis. We discovered that positioning of dynamic microtubules controls the asymmetric accumulation of E-cadherin. Microtubules are oriented preferentially along the dorso-ventral axis in Drosophila melanogaster embryonic epidermal cells, and thus more frequently contact E-cadherin at dorso-ventral cell-cell borders. This inhibits RhoGEF2, reducing membrane recruitment of Rho-kinase, and increasing a specific E-cadherin pool that is mobile when assayed by fluorescence recovery after photobleaching. This mobile E-cadherin is complexed with Bazooka/Par-3, which in turn is required for normal levels of mobile E-cadherin. Mobile E-cadherin-Bazooka prevents formation of multicellular rosette structures and cell motility across the segment border in Drosophila embryos. Altogether, the combined action of dynamic microtubules and Rho signaling determines the level and asymmetric distribution of a mobile E-cadherin-Bazooka complex, which regulates cell behavior during the generation of a patterned epithelium

Ensemble interactions in strained semiconductor quantum dots

Large variations in InxGa1-xAs quantum dot concentrations were obtained with simultaneous growths on vicinal GaAs [001] substrates with different surface step densities. It was found that decreasing dot-dot separation blueshifts all levels, narrows intersublevel transition energies, shortens luminescence decay times for excited states, and increases inhomogeneous photoluminescence broadening. These changes in optical properties are attributed to a progressive strain deformation of the confining potentials and to the increasing effects of positional disorder in denser dot ensembles

Unbound states in quantum heterostructures

We report in this review on the electronic continuum states of semiconductor Quantum Wells and Quantum Dots and highlight the decisive part played by the virtual bound states in the optical properties of these structures. The two particles continuum states of Quantum Dots control the decoherence of the excited electron – hole states. The part played by Auger scattering in Quantum Dots is also discussed

FoxO and Stress Responses in the Cnidarian Hydra vulgaris

Background: In the face of changing environmental conditions, the mechanisms underlying stress responses in diverse organisms are of increasing interest. In vertebrates, Drosophila, and Caenorhabditis elegans, FoxO transcription factors mediate cellular responses to stress, including oxidative stress and dietary restriction. Although FoxO genes have been identified in early-arising animal lineages including sponges and cnidarians, little is known about their roles in these organisms. Methods/Principal Findings: We have examined the regulation of FoxO activity in members of the well-studied cnidarian genus Hydra. We find that Hydra FoxO is expressed at high levels in cells of the interstitial lineage, a cell lineage that includes multipotent stem cells that give rise to neurons, stinging cells, secretory cells and gametes. Using transgenic Hydra that express a FoxO-GFP fusion protein in cells of the interstitial lineage, we have determined that heat shock causes localization of the fusion protein to the nucleus. Our results also provide evidence that, as in bilaterian animals, Hydra FoxO activity is regulated by both Akt and JNK kinases. Conclusions: These findings imply that basic mechanisms of FoxO regulation arose before the evolution of bilaterians an