bluuebunny/crossref_metadata_2025 huggingface dataset:
Solitary quotients of finite groups
Authors: Tărnăuceanu Marius
Published: January 2012

We introduce and study the lattice of normal subgroups of a group G that determine solitary quotients. It is closely connected to the well-known lattice of solitary subgroups of G, see [Kaplan G., Levy D., Solitary subgroups, Comm. Algebra, 2009, 37(6), 1873–1883]. A precise description of this lattice is given for some particular classes of finite groups.
On the structure vector field of a real hypersurface in complex two-plane Grassmannians
Authors: Machado Carlos , Pérez Juan
Published: January 2012

Considering the notion of Jacobi type vector fields for a real hypersurface in a complex two-plane Grassmannian, we prove that if a structure vector field is of Jacobi type it is Killing. As a consequence we classify real hypersurfaces whose structure vector field is of Jacobi type.
Approximate κ-state solutions to the Dirac-Yukawa problem based on the spin and pseudospin symmetry
Authors: Ikhdair Sameer
Published: January 2012

Using an approximation scheme to deal with the centrifugal (pseudo-centrifugal) term, we solve the Dirac equation with the screened Coulomb (Yukawa) potential for any arbitrary spin-orbit quantum number κ. Based on the spin and pseudospin symmetry, analytic bound state energy spectrum formulas and their corresponding upper- and lower-spinor components of two Dirac particles are obtained using a shortcut of the Nikiforov-Uvarov method. We find a wide range of permissible values for the spin symmetry constant C
s from the valence energy spectrum of particle and also for pseudospin symmetry constant C
ps from the hole energy spectrum of antiparticle. Further, we show that the present potential interaction becomes less (more) attractive for a long (short) range screening parameter α. To remove the degeneracies in energy levels we consider the spin and pseudospin solution of Dirac equation for Yukawa potential plus a centrifugal-like term. A few special cases such as the exact spin (pseudospin) symmetry Dirac-Yukawa, the Yukawa plus centrifugal-like potentials, the limit when α becomes zero (Coulomb potential field) and the non-relativistic limit of our solution are studied. The nonrelativistic solutions are compared with those obtained by other methods.
Neutrophil to lymphocyte count ratio as a biomarker of bacterial infections
Authors: Holub Michal , Beran Ondřej , Kaspříková Nikola , Chalupa Pavel
Published: January 2012

The implementation of new markers of bacterial infection into clinical practice is hindered by their costs. We assessed the potential use of the neutrophil to lymphocyte count ratio (NLCR) to discriminate between bacterial and viral infections. NLCR was evaluated in 45 patients with bacterial infections: 24 patients with viral infections and 18 healthy adults. The medians of NLCR were 11.73 in bacterial infections, 2.86 in viral infections and 1.86 in controls. The NLCR cut-off value of 6.2 exhibited a sensitivity value of 0.91 and a specificity value of 0.96 for bacterial infection. These results suggest a diagnostic potential for NLCR.
Musculoskeletal manifestations of mucopolysaccharidosis type VI and effects of enzyme replacement therapy
Authors: Marucha Jolanta , Jurecka Agnieszka , Różdżyńska-Świątkowska Agnieszka , Tylki-Szymańska Anna
Published: January 2012

The aim of this study was to describe the musculoskeletal manifestations of mucopolysaccharidosis VI and to assess the effectiveness of enzyme replacement therapy (ERT) with recombinant human arylsulfatase B on the bone and joint involvement in a patient with a severe phenotype of the disease. Before the initiation of ERT, the patient presented with significant range of motion (ROM) limitations at multiple joints. Flexion contractures were noticeable in all joints. After 48 weeks of ERT, improvement in active and passive shoulder flexion, as well as passive elbow and wrist flexion, was noticed. ROM improvements were reflected in patient’s enhanced self-care.
An Experimental and Numerical Study of Tip Vortex Cavitation
Authors: Szantyr J. , Flaszyński P. , Tesch K. , Suchecki W. , Alabrudziński S.
Published: January 2012

An Experimental and Numerical Study of Tip Vortex Cavitation

The article presents the results of the research project concerning tip vortex cavitation. This form of cavitation is very important in operation of many types of rotary hydraulic machines, including pumps, turbines and marine propellers. Tip vortex cavitation generates noise, vibration and erosion. It should be eliminated or significantly limited during the design of these types of machines. The objective of the project was to develop an accurate and reliable method for numerical prediction of tip vortex cavitation, which could serve this purpose. The project consisted of the laboratory experiments and numerical calculations. In the laboratory experiments tip vortex cavitation was generated behind a hydrofoil in the cavitation tunnel and the velocity field around the cavitating kernel was measured using the Particle Image Velocimetry method. Measurements were conducted in three cross-sections of the cavitating tip vortex for a number of angles of attack of the hydrofoil and for several values of the cavitation index. In the course of numerical calculations two commercial CFD codes were used: Fluent and CFX. Several available approaches to numerical modeling of tip vortex cavitation were applied and tested, attempting to reproduce the experimental conditions. The results of calculations were compared with the collected experimental data. The most promising computational approach was identified.
Vibration Analysis of Grid-Stiffened Circular Cylindrical Shells with Full Free Edges
Authors: Jam J. , Zadeh M. , Taghavian H. , Eftari B.
Published: January 2012

Vibration Analysis of Grid-Stiffened Circular Cylindrical Shells with Full Free Edges

Free vibration of grid stiffened circular cylindrical shells is investigated based on the first Love's approximation theory using Galerkin method. Full free edges are considered for boundary conditions. An equivalent stiffness model (ESM) is used to develop the analytical solution of the grid stiffened circular cylindrical shell. The effect of helical stiffeners orientation and some of the geometric parameters of the structure have been shown. The accuracy of the analysis has been examined by comparing results with those available in the literature and finite element approach.
Comparing combined gas tubrine/steam turbine and marine low speed piston engine/steam turbine systems in naval applications
Authors: Dzida Marek , Olszewski Wojciech
Published: January 2012

Comparing combined gas tubrine/steam turbine and marine low speed piston engine/steam turbine systems in naval applications

The article compares combined systems in naval applications. The object of the analysis is the combined gas turbine/steam turbine system which is compared to the combined marine low-speed Diesel engine/steam turbine system. The comparison refers to the additional power and efficiency increase resulting from the use of the heat in the exhaust gas leaving the piston engine or the gas turbine. In the analysis a number of types of gas turbines with different exhaust gas temperatures and two large-power low-speed piston engines have been taken into account. The comparison bases on the assumption about comparable power ranges of the main engine.
Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines
Authors: Korczewski Zbigniew
Published: January 2012

Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines

The third part of the article presents a method for detecting failures of the automatic engine control system with the aid of an exhaust gas temperature setter, specially designed and machined for this purpose. It also presents a procedure of identifying the operating tolerances and determining the diagnostic tolerances for the exhaust gas temperature recorded in the naval turbine engine during the start-up and acceleration processes. The diagnostic tolerances were determined using the statistic inference, based on the hypothesis about the normal distribution of the starting exhaust gas temperature dispersion at the initial time of engine operation. The above hypothesis was verified using the non-parametric statistic test χ2 for examining the consistency of the empirical distribution with the assumed normal distribution. As a result of the examination, satisfactory convergence of the compared distributions was obtained which made the basis for assuming the three-sigma limits of the diagnostic tolerance for the analysed engine control parameter.
The Effect of Beauveria Bassiana on Brazilian Poplar Moth Condylorrhiza Vestigialis (Lepidoptera: Crambidae)
Authors: do Amaral Dal Pogetto Mário , Wilcken Carlos
Published: January 2012

The Effect ofBeauveria Bassianaon Brazilian Poplar MothCondylorrhiza Vestigialis(Lepidoptera: Crambidae)

The Brazilian poplar moth is the most important pest of poplar plantations in Brazil. This research evaluated the effect ofBeauveria bassianaBals. (Vuill.) on the mortality and development ofCondylorrhiza vestigialisGuen. (Lepidoptera: Crambidae). The aim was to develop alternative methods for management of this pest. The pathogens were sprayed on poplar leaves and consequently, the pathogens reached the caterpillars.Bacillus thuringiensisvar.kurstakiBerliner was sprayed as the standard treatment. The spray for the control was distilled water. Both pathogensB. bassianaandB. thuringiensisaffected insect development with increase mortality at each stage of the insect cycle, reaching a satisfactory control level. Microbial control of Brazilian poplar moth withB. bassianais promising. Tests with other strains and species of pathogens, mainly under field conditions, were also encouraging. This is the first report about the action ofB. bassianaagainstC. vestigialis.
Influences of Botanical Pesticides and Biological Agents on Orius Laevigatus - Frankliniella Occidentalis Dynamics Under Greenhouse Conditions
Authors: Bonsignore Carmelo , Vacante Vincenzo
Published: January 2012

Influences of Botanical Pesticides and Biological Agents onOrius Laevigatus - Frankliniella OccidentalisDynamics Under Greenhouse Conditions

We assessed the influence of nine biopesticides on adults and larvae of western flower thrips (WFT),Frankliniella occidentalis(Pergande) and its predator, the anthocoridOrius laevigatus(Fieber) under Mediterranean greenhouse conditions. Trials were carried out in a strawberry crop where both species had naturally established. Foliar sprays were applied weekly for one month. Treatments did not provide sufficient control of larval and adultF. occidentalis. The negative effects on the dynamics of the predator were evident only with the use of some specific products. The botanical insecticides rotenone and neem, and the nematodeSteinernema feltiae(Filipjev) reducedO. laevigatusnumbers, and these effect are evident in the adult stage ofO. laevigatus. Such products have determined a reduction of the population of the predator from the first treatments even if the incidence was not very high. We conclude that the use of some botanical pesticides and nematodes against WFT is uneconomical and possibly disadvantageous where there is an established predator-prey population.
The Integration Between Trichogramma Evanescens West. (Hymenoptera: Trichogrammatidae) and Selected Bioinsecticides for Controlling the Potato Tuber Moth Phthorimaea Operculella (Zell.) (Lepidoptera: Gelechiidae) of Stored Potatoes
Authors: Mandour Nasser , Sarhan Awad , Atwa Dina
Published: January 2012

The Integration BetweenTrichogramma EvanescensWest. (Hymenoptera: Trichogrammatidae) and Selected Bioinsecticides for Controlling the Potato Tuber MothPhthorimaea Operculella(Zell.) (Lepidoptera: Gelechiidae) of Stored Potatoes

The efficacy of the egg-egg parasitoidTrichogramma evanescens(Hymenoptera: Trichogrammatidae) and certain bioinsecticides (e.g., Neemix, Virotecto, Agerin, Dipel 2x and Spinosad) for controlling the potato tuber moth (PTM),Phthorimaea operculella(Zeller) (Lepidoptera: Gelechiidae) under storage conditions was studied. Single and combined treatments ofT. evanescensand the bioinsecticides were tested. Neemix and spinosad were evaluated as spray treatments. Virotecto, Agerin and Dipel 2x were evaluated as dust and spray treatments. Data were recorded in terms of rate of infestation, reduction of infestation, number ofP. operculellapupae, and number of mines per 20 tubers as well as percentage of edible parts. Data revealed that the percentage of infestation in the control treatment was as high as in the Neemix treatment being 96.67 and 90% after one and two months of storage, respectively. Obviously, Spinosad and Dipel 2x were the most effective bioinsecticides in reducing tuber infestation and number ofP. operculellarecovered pupae. Virotecto and Agerin reduced rate of infestation and number of recoveredP. operculellapupae over that of the control, but their effect was significantly lower than that of Spinosad or Dipel 2x. Moreover, there were significant differences among treatments in the form of the number ofP. operculellatunnels and percentages of edible parts after two months in storage. Data further indicated that the integration between the tested bioinsecticides andT. evanescensenhanced the control ofP. operculella.Significant differences in percentages of infestation, edible parts, number of recovered pupae as well as number of mines in stored potatoes existed between individual treatments (withoutTrichogramma) and combined treatments.
Prevalence of Races and Biotypes of Ralstonia Solanacearum in India
Authors: Chandrashekara Krishnappa , Prasannakumar Mothukapalli , Deepa Manthirachalam , Vani Akella , Khan Abdul
Published: January 2012

Prevalence of Races and Biotypes ofRalstonia Solanacearumin India

Bacterial wilt caused byRalstonia solanacearumis the most destructive disease of plants. Fifty-seven isolates ofR. solanacearumcausing wilt on different host plantsviz., tomato (Solanum lycopersicum), brinjal (S. melongena), potato (S. tuberosum), bird of paradise (Strelitzia reginae), ginger (Zingiber officinale), chili (Capsicum annuum), capsicum (Capsicum annuum), davana (Artemisia pallens) and coleus (Coleus forskohlii) were collected from the different agro climatic zones of Karnataka and other parts of India. In this study, 57 isolates were differentiated into race on the basis of their pathogenicity and their ability to infect different host. The isolates were established as race-1. None of the isolates infected mulberry and banana. Fifty-four isolates oxidized and utilized both the disaccharides and sugar alcohols. These isolates were positioned as biovars-3 according to Haywards classification system. Three isolates from Kerala, two ginger, and one tomato strain were not able to utilize dulcitol and lactose. Hence, they were categorized into a new taxo group within the system and designated as biovar-3B for the first time in India. There were 54 isolates which were confirmed as race-1, biovar-3, and 3 isolates were confirmed as race-1, biovar-3B by morphological, physiological, biochemical and pathogenicity studies. Two sets of primers (OLI1 & Y2 and Y1 & Y2) were used in this study to authenticate the organism. Furthermore, the identity of the isolates was confirmed by a serological diagnostic kit obtained from the International Potato Research Center, Lima, Peru, and single chain variable fragment antibody specific toR. solanacearum.
The Significance of Alien and Invasive Slug Species for Plant Communities in Agrocenoses
Authors: Kozłowski Jan
Published: January 2012

The Significance of Alien and Invasive Slug Species for Plant Communities in Agrocenoses

This paper lists alien invasive species of slugs occurring on crops grown in the ground and under covers, as well as in adjacent habitats. It gives a description of their origin, distribution within Poland, frequency of occurrence in different habitats, and an evaluation of the danger to cultivated plants posed by particular slug species. Based on reports in the literature and the results of original research, basic data is presented concerning the biology and harmfulness of these slugs on crops. The potential risk of the spreading of invasive slug species is evaluated, as well as their adverse impact on crop plants. It has been concluded that a major risk to the biodiversity of agrocenoses and to cultivated plants is currently posed by the slugsArion lusitanicus, A. rufusandA. distinctus. These slugs are spreading rapidly within Poland, often occur in large numbers, and do significant damage to various species of plant.
Echinochloa Colonum Resistance to Bispyribac-Soduim in Egypt - Occurrence and Identification
Authors: El-Nady Mohamed , Hamza Amany , Derbalah Aly
Published: January 2012

Echinochloa ColonumResistance to Bispyribac-Soduim in Egypt - Occurrence and Identification

Identification and mechanism ofEchinochloa colonum(L.) resistance to bispyribac-soduim via physiological and anatomical differences between susceptible and resistant biotypes was investigated. The physiological and anatomical differences that were take into account were growth reduction, chlorophyll content reduction, protein analysis, lamina thickness and xylem vessel diameter in both susceptible and resistant biotypes ofE. colonum.The results showed the growth reduction fifty (GR50) of resistant biotype was 10.2 times higher than that of the susceptible biotypeE. colonumtreated with bispyribac-soduim. The chlorophyll content was highly reduced in the susceptible biotype relative to the resistant one ofE. colonumtreated with bispyribac-soduim. An anatomical test showed significant differences in the cytology of susceptible and resistant biotypes ofE. colonumtreated with bispyribac-soduim with respect to lamina thickness and xylem vessel diameter. Furthermore, leaf protein analysis showed significant differences between the susceptible and resistant biotypes ofE. colonumin the number and the density of protein bands. The resistance ofE. colonumto bispyribac-soduim may be due to the faster metabolism of bispyribac-soduim below the physiologically active concentration or the insensitivity of its target enzyme, (acetolactate synthase). These results implied the occurrence ofE. colonumresistance to bispyribac-soduim in Egypt and provide conclusive evidence that a single resistance mechanism alone cannot explain insensitivity inE. colonumto bispyribac-soduim.
Temporal variability of the selected flood parameters in the Biebrza River valley
Authors: Ignar Stefan , Maksymiuk-Dziuban Anna , Mirosław-Świątek Dorota , Chormański Jarosław , Okruszko Tomasz , Wysocki Paweł
Published: January 2012

Temporal variability of the selected flood parameters in the Biebrza River valley

The paper presents the application of the hydrodynamic one-dimensional model of river flow based on St Venant equations for calculation of annual floods characteristics in the Lower Biebrza River Basin situated in the Northeast of Poland. This model was combined with the Digital Elevation Model (DEM) for determining of area of flooding, its mean depth and flood volume. The model was calibrated using measurements of flood extent and verified comparing calculated flood extent to satellite images. The water level values calculated with the numerical model of flood-flow for cross-sections were next used to determine the digital model of the floodwater table in the valley. Then, inundation extent maps and water depth maps were calculated for whole area of the valley by overlaying the DEM and water table layers. This procedure, flood simulations with the hydrodynamic model and GIS analysis for determinations of inundation extent, was repeated for each day of the analyzed period of 1966-2000. A set of each year maximum calculated areas of flooding with related mean water depths and flood volumes was created and it was submitted to the trend analysis in order to determine possible change tendencies. Statistical analysis of three above described time series of annual flood characteristics was conducted with the use of moving average technique and linear regression method. Moving averages were calculate in two variants: with time step of 5 years and of 10 years. Next, linear trends were calculated by linear regression method. The results indicate that the developed hydrodynamic model of river flow combined with the DEM was useful for the calculation of annual maximum floods in the Lower Biebrza Valley and their parameters. Analysis of calculated flood parameters variability within the analyzed time period of 1961-2000 show decreasing trends for investigated area. This means that results of climate changes are perceptible in investigated area and they form serious danger to riparian wetlands.
BOD measuring and modelling methods - review
Authors: Siwiec Tadeusz , Kiedryńska Lidia , Abramowicz Klaudia , Rewicka Aleksandra , Nowak Piotr
Published: January 2012

BOD measuring and modelling methods - review

The article presents the method of measuring BOD in wastewater and characteristic different models which can by used for describing changes of BOD in next days. In the paper described eight models: Moore et al. (1950), Thomas (1950), Navone (1960), Fujimoto (1964), Hewitt et al. (1979), Adrian and Sanders (1992-1993) as well as Young and Clark (1965) used by Adrian and Sanders (1998), Borsuk and Stow (2000) and Manson et al. (2006). Comparison the models suggests that changing of BOD during the time are better describes by models second order or double exponential model (Manson et al. 2006) than models the first order.
Wear Resistance of Aluminized Steel Plates
Authors: Żaba K.
Published: January 2012

Wear Resistance of Aluminized Steel Plates

The results of the abrasion resistance measurements of aluminized steel strips are presented in the hereby paper. Steel strips of DX52D+AS120 grade, before and after a heat treatment at temperatures of 200-1000°C for 1 - 5760 minutes, were tested. Tests of the abrasion resistance were carried on in a specially built device: rotating disk - sample performing a plane-rotary motion, with an application of a lubricating medium. Examinations of the abrasion resistance were also performed by means of the block-on-ring tester. Estimations of a coating mass loss, roughness and thickness changes were carried on. The obtained results are illustrated by diagrams and macro- and micro-observations. Phase analysis investigations were also performed on samples selected after the abrasibility testing. The range of the heat treatment parameters - after which the Al-Si coating increased its abrasion resistance - was estimated.
Composite Layers with Ceramic Matrix Modified with Glassy Carbon Destined for Oil-Less Sliding Pairings
Authors: Posmyk A. , Wistuba H.
Published: January 2012

Composite Layers with Ceramic Matrix Modified with Glassy Carbon Destined for Oil-Less Sliding Pairings

The paper presents basic knowledge about producing and some results of tribological and metallographical research on composite layers with porous, anodic hard coating matrix which were modified with glassy carbon nanotubes. These composite layers were formed as surface layers of machine parts operating under conditions of sparse lubrication (limited lubrication) and friction in air. The layers were tested at sliding mating with EN-GJL-350 cast iron used for piston rings in combustion engines and air compressors. On the basis of the metallographical tests was the structure of the composite layer described. It was fount that on the surface of the oxide is a glassy carbon layer and in the pores of oxide are regullary carbon nanotubes. On the basis of the obtained results of tribological tests it was found that glassy carbon layer on the oxide surface shorts the wering-in time, and the glassy carbon nanotubes formed inside the pores of anodic hard coating upon EN-AW-6061 aluminum alloy prove to be effective solid lubricants and complement lubrication function of the graphite in cast iron. Consequently the coefficient of friction was lower than in case of nanotubes-free oxide layers.
Effect of the Gmaw and the Gmaw-P Welding Processes on Microstructure, Hardness, Tensile and Impact Strength of Aisi 1030 Steel Joints Fabricated by ASP316L Austenitic Stainless Steel Filler Metal
Authors: Kurşun T.
Published: January 2012

Effect of the Gmaw and the Gmaw-P Welding Processes on Microstructure, Hardness, Tensile and Impact Strength of Aisi 1030 Steel Joints Fabricated by ASP316L Austenitic Stainless Steel Filler Metal

In this study, medium-carbon steel (AISI 1030) plates of 10 mm thickness, were welded by using the synergic controlled pulsed (GMAW-P) and manual gas metal arc (GMAW) welding techniques. Constant wire feed speed, voltage, welding speed and gas flow rates (3.2 m/min, 22.5 V, 4 mm/s, 16 1/min) and ASP316L austenitic stainless steel filler metal were used in these techniques. The interface appearances of the welded samples were examined by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-Ray diffraction (X-RD). In order to determine mechanical properties of samples, the tensile, impact and microhardness tests were conducted. The GMAW-P joints of AISI 1030 steel couples showed superior tensile strength, less grain growth and narrower heat affected zone (HAZ) when compared with GMAW joints, and this was mainly due to lower heat input, fine fusion zone grain and higher fusion hardness.
Modeling of Oxide Precipitates Chemical Composition During Steel Deoxidization
Authors: Iwanciw J. , Podorska D. , Wypartowicz J.
Published: January 2012

Modeling of Oxide Precipitates Chemical Composition During Steel Deoxidization

The work analyses the possibilities of modeling the process of steel deoxidization from the view-point of thermodynamic equilibrium between liquid steel and oxide precipitates. Two calculation procedures were employed, which make use of WYK_STAL authors' program and commercial software FactSage. Two kinds of steel were taken into account, one with considerable titanium addition and the second without titanium. The variation of chemical composition of non-metallic precipitates with titanium concentration, aluminum addition and temperature was determined. The apparent influence of assumed thermodynamic model on the composition of non-metallic precipitate was stated.
Application of Mechanical Activation in Synthesizing Multiferroic Pb(Fe1/2Nb1/2)O3 Powders
Authors: Bochenek D. , Dercz G. , Oleszak D.
Published: January 2012

Application of Mechanical Activation in Synthesizing Multiferroic Pb(Fe1/2Nb1/2)O3 Powders

In the study, the method of high-energy powder milling - mechanical activation (MA) was used for synthesizing Pb(Fe1/2Nb1/2)O3 (PFN) powders. For the purpose of comparing the influence of high-energy milling on PFN synthesis, two groups of powder samples were used. The first mixture consisting of simple oxide powders; the second one consisting of compound oxide powders. The obtained powders were subjected to structural analysis with the use of XRD and Mőssbauer spectroscopy. Tests revealed that during the process of high-energy milling of initial constituents a partial synthesis of PFN material phases occurs. By comparing the two methods of PFN synthesizing it may be stated that mechanical activation in the case of a simple oxide mixture (PFN1) is equally effective as for a compound oxide mixture (PFN2).
Anomaly of the Work Hardening of Zn-Cu Single Crystals Oriented for Slip in Secondary Systems
Authors: Pieła K.
Published: January 2012

Anomaly of the Work Hardening of Zn-Cu Single Crystals Oriented for Slip in Secondary Systems

The copper alloyed (up to 1.5%) zinc single crystals oriented for slip in non-basal systems (orientation close to < 1120 >) were subjected to compression test within a range of temperatures of 77-293K. It has been stated, that Zn-Cu crystals exhibit characteristic anomalies of the thermal dependence of yield stress and of the strain hardening exponent. Both of them are related to the change in type and sequence of active non-basal slip systems: pyramidal of the 1storder {1011} < 1123 > (Py-1) and pyramidal of the 2ndorder {1122} < 1123 > (Py-2). The temperature anomaly of the yield stress results from the change of the slip from Py-2 systems to simultaneous slip in the Py-2 and Py-1 (Py-2 + Py-1) systems, occurring in the preyielding stage. On the other hand, sequential activation of pyramidal systems taking place in advanced plastic stage (i.e. the first Py-2 and next Py-2 + Py-1 systems) is responsible for temperature anomaly of strain hardening exponent. Increase in copper addition favors the activity of Py-2 systems at the expense of Py-1 slip, what leads to a drastic differences in plastic behavior of zinc single crystals.
Surface Properties of Nanoceramic Powders
Authors: Danelska A. , Szafran M.
Published: January 2012

Surface Properties of Nanoceramic Powders

The paper focuses on selected fragment of nanopowders surface studies made by author. The studies presented consist of viscosity measurements of ceramic slurries and ionic conductivity and pH determination of supernatants obtained by using of nanozirconia suspensions centrifugation. Three different nanozirconia powders were chosen to compare the influence of D-fructose on the viscosity of nano-ZrO2suspensions. Then the powders were centrifuged with water to leach soluble counter-ions. It was proved that the leaching has a SIGNIFICANT effect on the viscosity of nano-ZrO2suspension.
Fabrication, Structural and AC Impedance Studies of Layer-Structured Bi4Ti3O12 Ceramics
Authors: Bernard H. , Lisińska-Czekaj A. , Dzik J. , Osińska K. , Czekaj D.
Published: January 2012

Fabrication, Structural and AC Impedance Studies of Layer-Structured Bi4Ti3O12 Ceramics

In the present research bismuth titanate Bi4Ti3O12 (BiT) ceramics was synthesized by the standard solid-state reaction method from the mixture of oxides, followed by free sintering at temperature T=1000°C. BiT ceramics was studied in terms of its chemical composition (EDS), crystalline structure (X-ray), microstructure (SEM) and dielectric properties (ac technique of complex impedance spectroscopy) over a range of frequency (ƒ=100Hz to ƒ=1MHz) and temperature (T=200-500°C). Experimental results confirmed the phase formation. It was found that BiT ceramics crystallized in orthorhombic symmetry, best described with Fmmm space group and the following elementary cell parameters: a=5.409(6)°A, b=5.449(2)°A and c=32.816(2)°A. It was also found that BiT ceramics exhibited the plate-like microstructure and stoichiometric chemical composition. Impedance spectroscopy measurements showed contribution of three overlapping relaxation processes (three semicircles in the complex impedance diagrams were observed) ascribed to bulk, grain boundary and electrode/interface polarization phenomena. Impedance data were fitted to the corresponding equivalent circuit using the complex nonlinear least squares (CNLS) method. The ac conductivity for grains, grain boundaries and electrode processes was calculated from CNLS fit of the impedance data and thus the activation energy of ac conductivity (σAC) and relaxation (τ) was calculated for the three revealed components of the impedance spectra from the slopes of σAC and τ versus 1000/T plots (semi log scale) in the range of ΔT=200-500°C.
The Analysis of Laser Thermosplitting of Fragile Materials by Using of Special Geometry Beams
Authors: Shalupaev S. , Aleksiejuk M. , Nikitjuk Y. , Sereda A.
Published: January 2012

The Analysis of Laser Thermosplitting of Fragile Materials by Using of Special Geometry Beams

In this paper the numerical modeling of allocation of thermoelastic fields which are formed during controllable laser thermosplitting in fragile nonmetallic materials is executed within the limits of theory of elasticity. Modeling is executed for laser beams with a cross-section in the form of an ellipse, a circle, and the semi-ring and theirs combination. The classical circuit of realization of the given method consists of the superficial heating of a material by a laser beam and the aftercooling of this zone by means of a refrigerating medium. Thus the crack which is organized in the zone of refrigerating medium supply follows a laser beam along a treatment line. On the basis of thermoelastic fields allocation shown, that application of the classical circuit of the given method realization with the use of elliptic beams possesses a number of the disadvantages, one of which is the quick deflection of a crack from a line of influence of a laser beam and refrigerating fluid at treatment close to collateral border of the sample. Thus the crack is progressed in a direction to collateral border of the sample. It is displayed, that application of special geometry beams allows to diminish degree of effects of a treatment line closeness to boundary line of the sample on crack development. The positive effect is attained by forming a compression stress zone not only ahead and under field of a refrigerating medium effects where the crack is initialized and explicated, but also on each side of zone of a refrigerating medium effects, that in one's turn does not allow a crack to be deflected aside.
Fabrication of Light Ceramic Aggregate by Authothermal Sintering of Power Plant Ashes in the Rotary Furnace
Authors: Sokołowski J. , Łuczaj K. , Urbańska P.
Published: January 2012

Fabrication of Light Ceramic Aggregate by Authothermal Sintering of Power Plant Ashes in the Rotary Furnace

The inexpensive and reliable technology of the production of ceramic aggregate from coal ash, coal dust and mineral cement (clay, bentonite) optionally organic cement has been developed. The tecchnology is based on the method of sintering in high temperature. The conception of workings and the way of performance of the dryer of the humid aggregate and the rotary furnace in which the process will be carried on with no addition of the external fuel have been also developed. The implementation studies, partly granted by European Union, have been continued. The studies consisted ass follows: the laboratory research into the drying of coal ash granules, the compilation of technical parameters for the performance of a new shaft dryer by building semi-commercial model and defining parameters of working, the studyon the sintering in modernized semi-commercial rotary furnace. Currently process desing for final technical installation are being developed.
The Dispersion of Strong Field Dielectric Permittivity in (1-x)PMN-(x)PT Ceramics
Authors: Wawrzała P. , Skulski R.
Published: January 2012

The Dispersion of Strong Field Dielectric Permittivity in (1-x)PMN-(x)PT Ceramics

We propose the method of analysis of the dielectric permittivity measured in very strong electric fields. The method is based on the numeric calculations of derivative fromP - Ehysteresis loop. Such investigations have been performed for PMN-PT ceramics at various temperatures and frequencies. As a result we analyze the low frequency dispersion of the strong field dielectric permittivity.
Characterizations and Evaluations on the Bonding Quality of Molybdenum Disilicides
Authors: Lu L. , Qin W.
Published: January 2012

Characterizations and Evaluations on the Bonding Quality of Molybdenum Disilicides

In this study, we proposed a new method using the spark plasma sintering technique to bond ceramics to alloys. MoSi2and 316L stainless steel were chosen as sample materials and can be welded well with graded interlayers. We found that dense uniformed bondings were achieved because of the comparable coefficient of thermal expansion of the interlayers. Furthermore, such a compatibility between the graded interlayers prevented MoSi2with low toughness from the occurrence of microcracks resulted from the residual stresses formed during cooling of the bondings.
Alexandr Pavlovich Rasnitsyn - 75th birthday
Authors: Węgierek Piotr
Published: January 2012

Alexandr Pavlovich Rasnitsyn - 75th birthday
New Aleyrodidae (Hemiptera: Sternorrhyncha: Aleyrodomorpha) from Eocene Baltic amber
Authors: Drohojowska Jowita , Szwedo Jacek
Published: January 2012

New Aleyrodidae (Hemiptera: Sternorrhyncha: Aleyrodomorpha) from Eocene Baltic amber

A new genus and species of whitefly from Eocene Baltic amber is described.Paernis gregoriusgen. et sp. n. is placed in the subfamily Aleurodicinae. Other findings of Aleyrodidae including‘Aleyrodes’ aculeatusMenge, 1856 from Baltic amber are discussed.
Review of true bugs (Insecta: Hemiptera, Heteroptera) from the amber collection of the Museum of the Earth of PAS in Warsaw with some remarks on heteropteran insects from Eocene European amber
Authors: Popov Yuri , Kosmowska-Ceranowicz Barbara , Herczek Aleksander , Kupryjanowicz Janusz
Published: January 2012

Review of true bugs (Insecta: Hemiptera, Heteroptera) from the amber collection of the Museum of the Earth of PAS in Warsaw with some remarks on heteropteran insects from Eocene European amber

From all the information available on Heteroptera in the Palaeogene (European Eocene) amber found in the amber deposits of the Baltic and the Ukrainian (Rovno amber) regions, Central France (Oise), and also the Leipzig area (Saxonian amber), we can conclude that many representatives of true bugs (mainly Miridae, Microphysidae, Anthocoridae and Aradidae) known to us were associated mainly with coniferous vegetation (Early Tertiary European amber forests) and, consequently, were in constant contact with resin. The main findings regarding the taxonomy, number of species, a brief biology, palaeogeography and palaeontology, as well as a review of current literature sources, are given for every family contained in the amber collection of the Museum of the Earth of PAS in Warsaw. A summary table is also included. So far, over 160 genera and more than 240 species belonging to 41 families from all known ambers have been described. About 160 species and 100 genera from 25 modern heteropteran families, described from succinite - Baltic and Ukrainian (Rovno, Klesov) ambers - belong mostly to Miridae, Anthocoridae, Cimicoidea (Electrocoris), Microphysidae, Nabidae, Tingidae and Reduviidae. 12 families (120 inclusions) are represented in the collection of the Museum of the Earth: Saldidae (1), Ceratocombidae (1), Anthocoridae (9), Microphysidae (4), Miridae (73), Reduviidae (2), Nabidae (5), Thaumastocoridae (1), Tingidae (4), Aradidae (2), Piesmatidae (1), Lygaeidae (2), Cimicoidea (7) and Heteroptera incertae sedis (9). About 70% of fossils belong to the plant bugs (Miridae): 26.5% of these are represented by the Isometopinae and 43% by the Cylapinae subfamilies.
The oldest representatives of the subfamilies Meligethinae (Coleoptera: Nitidulidae) and Brontinae (Coleoptera: Silvanidae) from Baltic amber and some evolutionary notes
Authors: Kirejtshuk Alexandr
Published: January 2012

The oldest representatives of the subfamilies Meligethinae (Coleoptera: Nitidulidae) and Brontinae (Coleoptera: Silvanidae) from Baltic amber and some evolutionary notes

The paper describes Melipriopsis rasnitsyni gen. et sp. n. (Nitidulidae, Meligethinae) and Dendrobrontes popovi gen. et sp. n. (Silvanidae, Brontinae) from Baltic amber. The systematic position and phylogenetic significance of the new genera and species are discussed. A review of the fossils of the families Nitidulidae and Silvanidae is given. The genus Sinisilvana HONG, 2002, for which the family Sinisilvanidae HONG, 2002 was proposed, is considered as a genus with an unclear position within Silvanidae.
Revision of the genus Palaeopoecilostola Meunier, 1899 (Diptera: Limoniidae) from Baltic amber (Upper Eocene)
Authors: Kania Iwona , Krzemiński Wiesław , Gil Anna
Published: January 2012

Revision of the genus Palaeopoecilostola Meunier, 1899 (Diptera: Limoniidae) from Baltic amber (Upper Eocene)

A revision of the genus Palaeopoecilostola Meunier, 1899 (Diptera: Limoniidae) from Baltic amber (Upper Eocene) is presented. Redescriptions of four species of this genus are given and documented with photographs and drawings. The taxonomic ranks of two subspecies - Palaeopoecilostola longicornis longicornis Meunier, 1906 and Palaeopoecilostola longicornis parallela Alexander, 1931 - are elevated to species: P. longicornis stat. n. and P. parallela stat. n. Anepsiomyia atterraneus Nazarov, 1994 is recognized as new junior synonym of Palaeopoecilostola speciosa Meunier, 1906.
Biting midges (Diptera: Ceratopogonidae) in Eocene Baltic amber from the Rovno region (Ukraine)
Authors: Sontag Elżbieta , Szadziewski Ryszard
Published: January 2012

Biting midges (Diptera: Ceratopogonidae) in Eocene Baltic amber from the Rovno region (Ukraine)

The paper presents the results of an examination of 714 biting midges (Diptera: Ceratopogonidae) preserved in Baltic amber from the Rovno deposits in Ukraine. A new species - Leptoconops rovnensis sp. n. - is described and illustrated. 29 of the fossil species reported here have already been described from other deposits of Baltic amber: 26 of these were also found in amber from the Gulf of Gdańsk and 18 in amber from Bitterfeld (Saxony). The most common genera of biting midges in Ukrainian amber are also found in amber from Bitterfeld and the Gulf of Gdańsk, and with very much the same frequencies. The results indicate that the faunas of Ceratopogonidae enclosed in amber from Rovno, Bitterfeld and the Baltic are very similar, showing that they inhabited similar palaeoenvironments in the same palaeogeographic region.
Vibration-Induced Motor Responses of Infants With and Without Myelomeningocele
Authors: Saavedra Sandra L. , Teulier Caroline , Smith Beth A. , Kim Byungji , Beutler Benjamin D. , Martin Bernard J. , Ulrich Beverly D.
Published: January 2012

Background

The severity of myelomeningocele (MMC) stems both from a loss of neurons due to neural tube defect and a loss of function in viable neurons due to reduced movement experience during the first year after birth. In young infants with MMC, the challenge is to reinforce excitability and voluntary control of all available neurons. Muscle vibration paired with voluntary movement may increase motoneuron excitability and contribute to improvements in neural organization, responsiveness, and control.

Objectives

This study examined whether infants with or without MMC respond to vibration by altering their step or stance behavior when supported upright on a treadmill.

Design

This was a cross-sectional study.

Methods

Twenty-four 2- to 10-month-old infants, 12 with typical development (TD) and 12 with MMC (lumbar and sacral lesions), were tested. Infants were supported upright with their feet in contact with a stationary or moving treadmill during 30-second trials. Rhythmic alternating vibrations were applied to the right and left rectus femoris muscles, the lateral gastrocnemius muscle, or the sole of the foot. Two cameras and behavior coding were used to determine step count, step type, and motor response to vibration onset.

Results

Step count decreased and swing duration increased in infants with TD during vibration of the sole of the foot on a moving treadmill (FT-M trials). Across all groups the percentage of single steps increased during vibration of the lateral gastrocnemius muscle on a moving treadmill. Infants with MMC and younger infants with TD responded to onset of vibration with leg straightening during rectus femoris muscle stimulation and by stepping during FT-M trials more often than older infants with TD.

Conclusions

Vibration seems a viable option for increasing motor responsiveness in infants with MMC. Follow-up studies are needed to identify optimal methods of administering vibration to maximize step and stance behavior in infants.
Use of Quality Indicators in Physical Therapist Practice: An Observational Study
Authors: Jette Diane U. , Jewell Dianne V.
Published: January 2012

Background

The Patient Protection and Affordable Care Act and the Health Care and Education Reconciliation Act of 2010 contain provisions specific to health care quality that apply to physical therapists. Published evidence examining gaps in the quality of physical therapy services is limited.

Objective

The primary purpose of this study was to determine the use of quality indicators in physical therapist practice.

Design

This was an observational study.

Methods

All members of the Orthopaedic and Private Practice sections of the American Physical Therapy Association were invited to participate by completing an electronic survey. The survey included 22 brief patient descriptions, each followed by questions regarding the use of examinations and interventions based on the 2009 list of Medicare-approved quality measures. Separate multivariate logistic regression models were used to determine the odds ratios related to the performance of each examination and intervention on more than 90% of patients, given perceptions of its importance to care, the burden of performing it, and the level of evidence supporting its use.

Results

Participants (n=2,544) reported a relatively low frequency of performing examinations and interventions supporting primary and secondary prevention (3.6%–51.3%) and use of standardized measures (5.5%–35.8%). Perceptions of high importance and low burden were associated with greater odds of performing an examination or intervention. Importance and burden were more influential factors than the perceived availability of evidence to support use of identified techniques.

Limitations

The survey was not assessed for test-retest reliability. A low response rate was a source of potential bias.

Conclusion

The study findings suggest that physical therapists may not see themselves as providers of primary or secondary prevention services. Patient management strategies associated with these types of services also may be perceived as relatively unimportant or burdensome.
Constraint-Induced Therapy With Trunk Restraint for Improving Functional Outcomes and Trunk-Arm Control After Stroke: A Randomized Controlled Trial
Authors: Wu Ching-yi , Chen Yi-an , Lin Keh-chung , Chao Ching-ping , Chen Yu-ting
Published: January 2012

Background

Studies have suggested that constraint-induced therapy combined with trunk restraint (CIT-TR) improves arm movement and reduces trunk compensation. Whether participants who receive CIT-TR can translate the benefits to real-life circumstances awaits further investigation.

Objective

The effects of distributed CIT-TR (dCIT-TR) on motor function, daily function, quality of life (QOL), and arm-trunk control were investigated.

Design

The study was a single-blind, randomized controlled trial.

Setting

The study took place at 4 hospitals.

Participants

Participants were 57 people who had had a stroke 6 to 55 months earlier.

Intervention

Participants received a dose-matched intervention (2 hours per day, 5 days per week, for 3 weeks) of dCIT-TR, distributed constraint-induced therapy (dCIT), or control therapy.

Measurements

The Action Research Arm Test (ARAT), Motor Activity Log, Frenchay Activities Index (FAI), and Stroke Impact Scale (SIS) were used to evaluate motor function, daily function, and QOL. Data for reaching kinematics were recorded.

Results

Participants receiving dCIT-TR and dCIT exhibited higher overall scores on the ARAT, FAI, and hand function domain of the SIS and better quality of movement and larger amount of use (of the affected arm) on the Motor Activity Log than participants in the control group. Participants receiving dCIT-TR further demonstrated greater improvements on the ARAT grip subscale and FAI outdoor activities scale than participants receiving dCIT or participants in the control group. However, participants receiving dCIT showed greater improvements on the strength domain of the SIS after training than participants receiving dCIT-TR or participants in the control group.

Limitations

Research with a larger sample size is needed.

Conclusions

Participants who received dCIT-TR were able to translate gains in arm-trunk control into functional performance and QOL, specifically in grip function and outdoor activities. A long-term study to examine the recovery course for force output may be needed to evaluate people's perception of less improvement in strength after dCIT-TR.