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RATIONALE Although the structure of atomic switch Ge2Sb2Te5 (GST) thin films is well established, the composition of the clusters formed in the plasma plume during pulsed-laser deposition (PLD) is not known. Laser Desorption Ionization Time-of-Flight Mass Spectrometry (LDI-TOF MS) is an effective method for the generation and study of clusters formed by laser ablation of various solids and thus for determining their structural fragments. METHODS LDI of bulk or PLD-deposited GST thin layers and of various precursors (Ge, Sb, Te, and Ge-Te or Sb-Te mixtures) using a nitrogen laser (337 nm) was applied while the mass spectra were recorded in positive and negative ion modes using a TOF mass spectrometer equipped with a reflectron while the stoichiometry of the clusters formed was determined via isotopic envelope analysis. RESULTS The singly negatively or positively charged clusters identified from the LDI of GST were Ge, Ge2, GeTe, Ge2Te, Ten (n = 1–3), GeTe2, Ge2Te2, GeTe3, SbTe2, Sb2Te, GeSbTe2, Sb3Te and the low abundance ternary GeSbTe3, while the LDI of germanium telluride yielded GemTen+ clusters (m = 1–3, n = 1–3). Several minor Ge-H clusters were also observed for pure germanium and for germanium telluride. Sbn clusters (n = 1–3) and the formation of binary TeSb, TeSb2 and TeSb3 clusters were detected when Sb2Te3 was examined. CONCLUSIONS This is the first report that elucidates the stoichiometry of GemSbnTep clusters formed in plasma when bulk or nano-layers of GST material are ablated. The clusters were found to be fragments of the original structure. The results might facilitate the development of PLD technology for this memory phase-change material. Copyright © 2014 John Wiley & Sons, Ltd.

The electric properties of LiI containing chalcohalide glasses in the system Ga2S3–GeS2 were studied by means of impedance spectroscopy and potentiostatic chronoamperometry. Two sets of the samples were prepared by direct synthesis from elements and compounds in evacuated quartz ampoules. The prepared glasses were as follows: xLiI–xGa2S3–(100−2x)GeS2, x = 15, 20, 25 and 20LiI–xGa2S3–(80−x)GeS2, x = 0, 5, 10, 15 and 20. In the first set the concentration of LiI increased and the second set was prepared to study the influence of Ga2S3 on the properties of the glasses. Additional aim of this work was to compare the electric properties of LiI containing Ga2S3–GeS2 glasses with analogous AgI containing Ga2S3–GeS2 glasses recently studied by us. The conductivity of the LiI containing glasses in the Ga2S3–GeS2 system was higher and the activation energy was lower than in the analogous AgI containing system. The residual electronic (hole) conductivity remained similar in both systems being almost negligibly low. Raman spectroscopy proved the influence of LiI as well as Ga2S3 on glass structure, however interpretation of Raman spectra of these glasses is complicated due to small mass difference between gallium and germanium.

Thin films of AgSbS(2) are important for phase-change memory applications. This solid is deposited by various techniques, such as metal organic chemical vapour deposition or laser ablation deposition, and the structure of AgSbS(2)(s), as either amorphous or crystalline, is already well characterized. The pulsed laser ablation deposition (PLD) of solid AgSbS(2) is also used as a manufacturing process. However, the processes in plasma have not been well studied. We have studied the laser ablation of synthesized AgSbS(2)(s) using a nitrogen laser of 337 nm and the clusters formed in the laser plume were identified. The ablation leads to the formation of various single charged ternary Ag(p)Sb(q)S(r) clusters. Negatively charged AgSbS(4) (-), AgSb(2)S(3) (-), AgSb(2)S(4) (-), AgSb(2)S(5) (-) and positively charged ternary AgSbS(+), AgSb(2)S(+), AgSb(2)S(2) (+), AgSb(2)S(3) (+) clusters were identified. The formation of several singly charged Ag(+), Ag(2) (-), Ag(3) (-), Sb(3) (+), Sb(3) (-), S(8) (+) ions and binary Ag(p)S(r) clusters such as AgSb(2) (-), Ag(3)S(-), SbS(r) (-) (r = 1-5), Sb(2)S(-), Sb(2)S(2) (-), Sb(3)S(r) (-) (r = 1-4) and AgS(2) (+), SbS(+), SbS(2) (+), Sb(2)S(+), Sb(2)S(2) (+), Sb(3)S(r) (+) (r = 1-4), AgSb(2) (+) was also observed. The stoichiometry of the clusters was determined via isotopic envelope analysis and computer modeling. The relation of the composition of the clusters to the crystal structure of AgSbS(2) is discussed.

Density functional/molecular dynamics simulations have been performed to determine structural and other properties of amorphous Ag/Ge/S and Ge/S alloys. In the former, the calculations have been combined with experimental data (x-ray and neutron diffraction, extended x-ray absorption fine structure). Ag/Ge/As alloys have high ionic conductivity and are among the most promising candidates for future memristor technology. We find excellent agreement between the experimental results and large-scale (500 atoms) simulations in Ag/Ge/S, and we compare and contrast the structures of Ge/S and Ag/Ge/S. The calculated electronic structures, vibrational densities of states, ionic mobilities, and cavity distributions of the amorphous materials are discussed and compared with data on crystalline phases where available. The high mobility of Ag in solid state electrolyte applications is related to the presence of cavities and can occur via jumps to a neighbouring vacant site.

Density functional/molecular dynamics simulations and experimental data (x-ray and neutron diffraction, extended x-ray absorption fine structure) have been combined to determine structural and other properties of amorphous ${\text{AsS}}_{2}$ and $\text{Ag}{\text{AsS}}_{2}$. These semiconductors represent the two small regions of the Ag-As-S ternary diagram where homogeneous glasses form, and they have quite different properties, including ionic conductivities. We find excellent agreement between the experimental results and large-scale (over 500 atoms) simulations, and we compare and contrast the structures of ${\text{AsS}}_{2}$ and $\text{Ag}{\text{AsS}}_{2}$. The calculated electronic structures, vibrational densities of states, ionic mobilities, and cavity distributions of the amorphous materials are discussed and compared with data on crystalline phases where available. The high mobility of Ag in solid state electrolyte applications is coupled to the large cavity volume in ${\text{AsS}}_{2}$ and local modifications of the covalent As-S network in the presence of Ag.

The structure of Ag-doped GeS3 glasses (0, 15, 20, 25 at.% Ag) was investigated by diffraction techniques and extended x-ray absorption fine structure measurements. Structural models were obtained by fitting the experimental datasets simultaneously by the reverse Monte Carlo simulation technique. It is observed that Ge has mostly S neighbours in GeS3, but Ge-Ge bonds appear already at 15% Ag content. Sulfur has ~2 S/Ge neighbours over the whole concentration range, while the S-Ag coordination number increases with increasing Ag content. Ag-Ag pairs can already be found at 15% Ag. The Ag-S mean coordination number changes from 2.17 +/- 0.2 to 2.86 +/- 0.2 between 15% and 25% Ag content. Unlike the As-S network in AsS2-25Ag glass, the Ge-S network is not fragmented upon Ag-doping of GeS3 glass.

The scope of this article is focused on general analysis of errors and uncertainties possibly arising from CFD-to-schlieren pictures matching. Analysis is based on classic analytical equations. These are firstly evaluated with the presumption of constant density gradient along the ray course. In other words, the deflection of light-ray caused by density gradient is negligible in compare to the cross size of constant gradient area. It is the aim of this work to determine, whether this presumption is applicable in case of supersonic air-to-air ejector. The colour and black and white schlieren pictures are carried out and compared to CFD results. Simulations had covered various eddy viscosities. Computed pressure gradients are transformed into deflection angles and further to ray displacement. Resulting computed light- ray deflection is matched to experimental results.

In this work, we try to find the best setting of Computational Fluid Dynamic solver available for the problems in the field of supersonic internal flows. We used the supersonic air-toair ejector to represent the typical problem in focus. There are multiple oblique shock waves, shear layers, boundary layers and normal shock interacting in the supersonic ejector making this device typical in field of supersonic inner flows. Modeling of shocks in general is demanding on the physical model of fluid, because ordinary conservation equation does not conform to real conditions in the near-shock region as found in many works. From these reasons, we decided to take special care about solver setting in this article by means of experimental approach of color Schlieren pictures and pneumatic measurement. Fast pressure transducers were used to measure unsteady static pressure in regimes with normal shock in mixing chamber. Physical behavior of ejector in several regimes is discussed. Best choice of eddy-viscosity setting is discussed on the theoretical base. The final verification of the k-ω SST is done on the base of comparison between experiment and numerical results., {"references":["Breitkopf, P. and Coelho, R. F. Multidisciplinary design optimization in\ncomputational mechanics: Wiley-ISTE, 2010. ISBN-10 1848211384.","Hynek, J. Genetic algorithms and genetic programing (in Czech).\nPrague : Grada Publishing ,a. s., 2008. ISBN 978-80-247-2695-3.","Dvoř├ík, V. and Kol├íř, J. Shape optimization of supersonic ejectors with\nseveral primary nozzles. Lisboa, Portugal : In the 2nd International\nConference on Engineering Optimization, 6.-9. september 2010. ISBN\n978-989-96264-3-0.","Dvoř├ík, V. Shape optimization of supersonic ejector for supersonic\nwind tunnel. s.l. : In.: Applied and Computational Mechanics, 2010. pp.\n15-24. ISSN 1802-680X.","Kol├íř, J. and ┼áafař├¡k, P. Interaction of oblique shock wave with shear\nlayer. Plzeň : In Proceedings of the International Conference XXVII:\nMeeting of Departments of Fluid Mechanics and Thermomechanics,\n2008. pp. 163-170. ISBN 978-80-7043-666-0.","Moeckel, W. E. Interaction of oblique shock waves with regions of\nvariable pressure, entropy and energy. Washington : NACA, 1952. TN\n2725.","Shapiro, A. H. The dynamics and thermodynamics of compressible\nfluid flow. New York : The Ronald Press Company, 1953. ISBN\n0826080758.\n8] Versteeg, H. K. and Malalasekera, W. An Introduction to\nComputational fluid dynamics, The Finite Volume Method: Pearson\nEducation Limited 2007, ISBN 978-0-13-127498-3.","Wilcox, D. Reassessment of the scale determining equation for\nadvanced turbulent models. 1988. AIAA J. 26 (11),1299-1310.\n[10] Menter, F. R. Two-equations Eddy-viscosity turbulence models for\nengineering applications. 1994. AIAA J. 32(8), 1598-1605.\n[11] Inc., Fluent. Fluent user documentation. Lebanon : s.n., 2006.\nfrom the biography."]}

INTRODUCTION For many years, scientific research has considered the relationships between the landscape and human health. Increasing rates of environmental changes are dramatically altering patterns of human health at the community, regional and global scales. The emergence of tick-borne diseases (TBD) illustrates the impact that environmental changes can have on human health. Integration of modern geoinformation technologies into landscape epidemiology can contribute significantly to the development and implementation of new disease-surveillance tools. The theory of landscape epidemiology offers the opportunity to use the landscape as a key to the identification of the spatial and temporal distribution of disease risk. Key environmental elements – including elevation, temperature, rainfall and humidity – influence the presence, development, activity and longevity of pathogens, vectors and zoonotic reservoirs of infection, and their interactions with humans (Meade, Florin & Gesler, 1988). The same environmental variables influence distribution of vegetation type as landscape elements and patterns of disease. Remote sensing (RS) from aircraft and satellites can be used to describe landscape elements that influence the patterns and prevalence of disease. In addition, geographical information systems (GIS) provide tools for modelling spatially their occurrence in space and time. Ticks are ideally suited to GIS and RS applications owing to their close ties with the ecosystem. This relationship is determined by: (1) the type of host–parasite association (most important vector species are three-host ticks); (2) specific requirements of the microclimate; and (3) dependence on clearly defined types of plant associations which both reflect the microclimatic conditions of a habitat occupied by ticks, and also influence them.

Periosteal Ewing's sarcoma is an uncommon, but well documented origin of this malignant condition with radiographic signs, different from intramedullary growing tumours. Imaging modalities like CT or MRI supply proof of macroscopically intact endosteal cortical surface and free medullary cavity in long bones affected by this periosteal type of malignancy. Definite confirmation is valid after a careful microscopic investigation of the resected specimen. The prognosis of this type of Ewing's sarcoma may be more favourable than that of the central type. Early diagnosis and therapy are thus essential. A clinical survey of six observations is given.

Short-term intensity oscillations of precipitating and quasitrapped electrons ( E e > 40 keV) with characteristic periods from 5–100 s are investigated. Occurrence of such pulsations is studied in dependence on geomagnetic activity ( K p -indices), L-B coordinates, plasmapause position and other geophysical parameters.

From a number of samples of Spheron DEAE-1000 of various nominal capacities, fully quaternized derivatives TEAE of different nominal capacities were prepared. A series of derivatives quaternized to various degrees was prepared from Spheron DEAE-1000 of high nominal capacity. All these products were fully analyzed and tested by sorption of serum albumin under static and dynamic conditions and retention of chymotrypsinogen during isocratic elution. The results obtained were compared. The chromatographic properties of Spheron TEAE are illustrated by separation of an artificial mixture of proteins (lysozyme, chymotrypsinogen and serum albumin). The separation of cellulolytic enzymes on the DEAE and TEAE derivatives was compared under identical conditions. The chromatographic properties of a partially quaternized derivative of QAE-Spheron 40 were characterized by the dependence of the retention of oligogalacturonic acids on their degree of polymerization. Older types of strongly basic Spheron ion exchangers are discussed, as well as some analytical methods for the determination of quaternization degree, pH dependence of the static sorption of serum albumin on Spheron ion exchangers and the stability of strongly basic Spheron derivatives toward spontaneous loos of amines.

The resistance of pulmonary vessels rises if perfused with a solution the acidity of which is by 0·02–0·06 units pH less than that of the arterial blood. It supports the assumption that the perfusion of the particular lobules of the lung is controlled by the pH of the blood entering the pulmonary venules.

A procedure using heat inactivation and L-phenylalanine inhibition to quantitate the activities of bone, liver and intestinal alkaline phosphatase isoenzymes in human serum was confirmed by alkaline phosphatase isoenzyme analysis using an electrophoretic procedure. The results of this assay were compared with the radionuclear 85Sr test, and gamma-glutamyl transpeptidase activity in a group of patients with hepatobiliary and bone diseases.

Die Verletzungen durch den elektrischen Strom beschaftigen den Rontgenologen, trotz der steigenden Ausdehnung der elektrotechnischen Anlagen und der vielfachen Benutzung des elektrischen Stromes, nicht gerade haufig, weil die meisten im taglichen Leben vorkommenden Unfalle harmlos verlaufen und die Betroffenen uberhaupt nicht in arztliche Pflege kommen. Die anderen, bei denen die Einwirkung des elektrischen Stromes zu betrachtlichen traumatischen Veranderungen gefuhrt hat, befinden sich in der Pflege verschiedenster Anstalten, was den Uberblick uber die wirkliche Haufigkeit des Trauma electricum erschwert.