bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decreased anticoagulant response to tissue factor pathway inhibitor type 1 in plasmas from patients with lupus anticoagulants
Authors: Liestøl Sigurd , Sandset Per Morten , Jacobsen Eva Marie , Mowinckel Marie‐Christine , Wisløff Finn 
Published: November 2006

SummaryInhibition of tissue factor pathway inhibitor type 1 (TFPI) is one of the mechanisms by which lupus anticoagulants (LA) may upregulate tissue factor (TF) activity. We wanted to examine whether purified immunoglobulin G (IgG) from patients with LA may interfere with the ability of TFPI to inhibit ex vivo TF‐induced thrombin generation. The endogenous thrombin potential (ETP) in pooled normal plasma (PNP) supplemented with IgG from either patients with LA or controls was determined in the absence or presence of recombinant TFPI (rTFPI). In the presence of a heparin neutraliser, the ETP was also determined in plasmas from patients with LA and controls before and after heparin injection in order to quantify the anticoagulant effect of heparin‐releasable TFPI in vivo. Compared with IgG from controls (n = 14), IgG from patients with LA (n = 28) induced a wide range of enhancing or inhibitory effects on the ETP in PNP. The response to rTFPI in PNP with IgG from patients with LA correlated inversely with thrombin generation (rs = 0·637, P = 0·0003). Correspondingly, the relative inhibition of ETP in postheparin plasmas was smaller for patients (n = 11) than for controls (n = 9) (32% vs. 68%, P = 0·007). Our findings support the hypothesis that TFPI anticoagulant activity is inhibited in some patients with LA.
Microstructural analysis of iron aluminide formed by self‐propagating high‐temperature synthesis mechanism in aluminium matrix composite
Authors: OLSZÓWKA‐MYALSKA ANITA , MAZIARZ WOJCIECH 
Published: November 2006

SummaryAn aluminium matrix composite with iron aluminide formed in situ as a result of self‐propagated high‐temperature synthesis was examined. The structural characteristics of the reinforcement investigated by scanning electron microscopy and transmission electron microscopy methods are presented. Iron aluminide particles with a very fine grain size and of two shapes, cubic and needle‐like, were observed. No differences in their phase composition were found by the selective electron diffraction pattern method. The composite reinforcement formed in the early stage of self‐propagating high‐temperature synthesis consisted only of the Al3Fe phase.
Evolution of rapidly solidified NiAlCu(B) alloy microstructure
Authors: CZEPPE TOMASZ , OCHIN PATRICK 
Published: November 2006

SummaryThis study concerned phase transformations observed after rapid solidification and annealing at 500, 700 and 800 °C in 56.3 Ni‐39.9 Al‐3.8 Cu‐0.06 B (E1) and 59.8 Ni‐36.0 Al‐4.3 Cu‐0.06 B (E2) alloys (composition in at.%). Injection casting led to a homogeneous structure of very small, one‐phase grains (2–4 µm in size). In both alloys, the phase observed at room temperature was martensite of L10 structure. The process of the formation of the Ni5Al3 phase by atomic reordering proceeded at 285–394 °C in the case of E1 alloy and 450–550 °C in the case of E2 alloy. Further decomposition into NiAl (β) and Ni3Al (γ′) phases, the microstructure and crystallography of the phases depended on the path of transformations, proceeding in the investigated case through the transformation of martensite crystallographic variants. This preserved precise crystallographic orientation between the subsequent phases, very stable plate‐like morphology and very small β + γ′ grains after annealing at 800 °C.
Analytical transmission electron microscopy and electron diffraction for characterization of multiphase Ni‐P‐Ti surface layer on Ti‐6Al‐4V alloy
Authors: CZYRSKA‐FILEMONOWICZ A. , BUFFAT P. A. 
Published: November 2006

SummaryThe microstructure, chemical and phase composition of the hard Ni‐P‐Ti layer formed on the Ti‐6Al‐4V alloy after duplex surface treatment were investigated by light microscopy, X‐ray diffraction, scanning electron microscopy and analytical/high‐resolution transmission electron microscopy. These investigations showed that the improved mechanical and tribological properties of the surface‐treated alloy were related to the presence of a multilayered microstructure containing several phases from the Ni‐Ti‐P‐Al system.
Microstructure evolution in age‐hardenable aluminium alloy during processing by hydrostatic extrusion
Authors: LEWANDOWSKA M. 
Published: November 2006

SummaryIn the present work, scanning and transmission electron microscopy were used to investigate the microstructural evolution occurring during the hydrostatic extrusion of an age‐hardenable aluminium alloy. It was shown that processing by hydrostatic extrusion leads to grain refinement to 95 nm in equivalent diameter. Hydrostatic extrusion also influences the geometrical parameters of two different types of particle: intermetallic inclusions and precipitates. The intermetallic inclusions slightly decrease in mean equivalent diameter, but their size remains at the micrometre level. The precipitates are fragmented to nanoscale spherical particles, and their evolution delays the process of grain refinement.
Transmission electron microscopy characterization of the erbium silicide formation process using a Pt/Er stack on a silicon‐on‐insulator substrate
Authors: ŁASZCZ A. , KĄTCKI J. , RATAJCZAK J. , TANG XIAOHUI , DUBOIS E. 
Published: November 2006

SummaryVery thin erbium silicide layers have been used as source and drain contacts to n‐type Si in low Schottky barrier MOSFETs on silicon‐on‐insulator substrates. Erbium silicide is formed by a solid‐state reaction between the metal and silicon during annealing. The influence of annealing temperature (450 °C, 525 °C and 600 °C) on the formation of an erbium silicide layer in the Pt/Er/Si/SiO2/Si structure was analysed by means of cross‐sectional transmission electron microscopy. The Si grains/interlayer formed at the interface and the presence of Si grains within the Er‐related layer constitute proof that Si reacts with Er in the presence of a Pt top layer in the temperature range 450–600 °C. The process of silicide formation in the Pt/Er/Si structure differs from that in the Er/Si structure. At 600 °C, the Pt top layer vanishes and a (Pt–Er)Six system is formed.
Structure and properties of an alumina/amorphous‐alumina/platinum catalytic system deposited on FeCrAl steel
Authors: RESZKA K. , MORGIEL J. , RESZKA J. 
Published: November 2006

SummaryWe have investigated the properties and structure of alumina films obtained as a result of thermal oxidation of 0H18J5 steel under a mixture of SO2 and O2 atmosphere and then covered with layers of magnetron‐sputtered alumina and platinum. The catalytic tests and transmission electron microscopy investigations reveal that θ‐Al2O3 films containing acidic and basic sites are distinguished by high catalytic activity, whereas amorphous and α‐Al2O3 films show neutral activity. The platinum films deposited on them contribute to the enrichment of the laminar system with basic sites, and consequently raise the catalytic activity of the system. The investigations performed indicate that the catalytic activity of the system may be tailored to the desired level by the control of the thickness of the individual layers of coating.
Wavelength‐ and energy‐dispersive Electron Probe Microanalysis (EPMA) measurements with non‐perpendicular incidence of the electron beam
Authors: BASTIN G. F. , OBERNDORFF P. J. T. L. , HEIJLIGERS H. J. M. , DIJKSTRA J. M. 
Published: November 2006

SummaryA database of 416 wavelength‐ and energy‐dispersive EPMA measurements on tilted specimens of NiAl, TiO2 and Ti3Al is presented. The analyses were performed between 10 and 30 kV and the tilt angles were varied between 0° and 60° in seven steps. The necessary hardware modifications for the specimen holder are discussed, as well as the various focusing techniques used in the measurements. A comparison between the experimental data, the calculations of our proza96t program and the results of Monte Carlo simulations shows that up to 50° tilt the predictions of our software are more than satisfactory. At larger tilt angles some deviations become noticeable. The Monte Carlo simulations appear to produce deviations at a somewhat earlier stage already, for reasons as yet unknown.
Scanning and transmission electron microscopy microstructure characterization of mechanically alloyed Nb–Ti–Al alloys
Authors: ROZMUS MAGDALENA , BLICHARSKI MAREK , DYMEK STANISŁAW 
Published: November 2006

SummaryResults are presented of an investigation of the microstructure development during mechanical alloying and following consolidation of an Nb15Ti15Al alloy. The alloy was synthesized from elemental as well as pre‐alloyed powders. The microstructure of this material was examined by transmission electron microscopy, scanning electron microscopy and X‐ray diffraction. The use of pre‐alloyed TiAl powder for synthesis of the Nb15Ti15Al alloy meant that a much shorter time was required to complete the mechanical alloying process compared with the synthesis of elemental powders. The investigation indicates that three phases were present in the consolidated materials: the Nb solid solution, the Nb3Al intermetallic phase and the dispersoid.
Scanning electron microscopy and transmission electron microscopy microstructural investigation of high‐speed tool steel after Nd:YAG pulsed laser melting
Authors: KAC S. , KUSINSKI J. , ZIELINSKALIPIEC A. , WRONSKA I. 
Published: November 2006

SummaryThis article presents the microstructure of a pulsed Nd:YAG laser‐melted high‐speed steel, namely HS6‐5‐2. The high chemical homogeneity and fine structure of the melted zone was attributed to high cooling rates due to the short duration of interaction with the Nd:YAG pulsed laser radiation and the relatively small volume of the melted material. The structure obtained in the surface layer after laser melting has a high level of hardness and shows improved wear resistance.
Cathodoluminescence in transmission electron microscopy
Authors: STRUNK H. P. , ALBRECHT M. , SCHEEL H. 
Published: November 2006

SummaryWe describe a cathodoluminescence spectrometer that is attached to an analytical transmission electron microscope. After a brief consideration of the set‐up and the peculiarities of recording spectra and of mapping defect distributions in panchromatic and monochromatic cathodoluminescence, we discuss two examples of applications. Emphasis is placed on the potential for obtaining novel information about materials and processes on a microscopic and a nanoscopic scale by combining cathodoluminescence with the structural and chemical information for the same site of the specimen. We select an example concerning the role of In distribution in light emission from InGa/GaN quantum wells and a second one concerning the analysis of the initial electron radiation damage of Cu(In,Ga)Se2 photovoltaic films.
In situelectron beam induced current measurements of the local thickness in semiconductor devices
Authors: CZERWINSKI A. , PŁUSKA M. , RATAJCZAK J. , KATCKI J. 
Published: November 2006

SummaryA quantitative electron beam induced current method is shown, applicablein situfor electron beam current measurement on a semiconductor sample without the need for a Faraday cup. As a validation technique, the measurement of top overlayer thickness in the semiconductor structure was chosen for two reasons. First, the measured thickness is easily verified using the same electron microscope in the secondary electron mode by measuring the layer thickness at the layer edges. Second, the measurement of a layer thickness and its local variations constitute an important issue in semiconductor processing and characterization. The proposed method is used in the planar view of the sample, and also for locations far from the layer edges. Quasi‐three‐dimensional maps of the thickness spatial distribution are presented.
Elimination of scanning electron microscopy image periodic distortions with digital signal‐processing methods
Authors: PŁUSKA M. , CZERWINSKI A. , RATAJCZAK J. , KĄTCKI J. , RAK R. 
Published: November 2006

SummaryElectromagnetic interference is one of the main distortion sources in scanning electron microscopy. Electromagnetic interference‐generated scanning electron microscopy image distortions are usually visible as edge blur (at low scan rates) or vibration (at high scan rates). Hardware solutions to this problem, e.g. electrostatic and magnetic shielding, are expensive and, in some cases, difficult to implement. The current investigations led to a significant decrease in the periodic distortions by a novel adaptation of software‐based digital signal processing to scanning electron microscopy problems, without any hardware modification.
Buried amorphous‐layer impact on dislocation densities in silicon
Authors: WZOREK M. , KĄTCKI J. , PŁUSKA M. , RATAJCZAK J. , JAROSZEWICZ B. , DOMAŃSKI K. , GRABIEC P. 
Published: November 2006

SummaryThe impact of amorphous layers on dislocation densities in silicon piezoresistors was investigated by means of transmission electron microscopy and chemical etching. Mechanical bevel polishing at a shallow angle and selective etching were applied to assess the dislocation depth distributions. It was found that, despite the presence of additional defects after recrystallization, the initial presence of a buried amorphous layer reduced, after annealing, the dislocation density in the depletion region of a p–n junction, compared with the case of a shallower, surface amorphous layer.
Wing scale microstructures and nanostructures in butterflies − natural photonic crystals
Authors: VÉRTESY Z. , BÁLINT Zs. , KERTÉSZ K. , VIGNERON J. P. , LOUSSE V. , BIRÓ L. P. 
Published: November 2006

SummaryThe aim of our study was to investigate the correlation between structural colour and scale morphology in butterflies. Detailed correlations between blue colour and structure were investigated in three lycaenid subfamilies, which represent a monophylum in the butterfly family Lycaenidae (Lepidoptera): the Coppers (Lycaeninae), the Hairstreaks (Theclinae) and the Blues (Polyommatinae). Complex investigations such as spectral measurements and characterization by means of light microscopy, scanning electron microscopy and transmission electron microscopy enabled us to demonstrate that: (i) a wide array of nanostructures generate blue colours; (ii) monophyletic groups use qualitatively similar structures; and (iii) the hue of the blue colour is characteristic for the microstructure and nanostructure of the body of the scales.
The structure and mechanical properties of amorphous and nanocrystalline Fe–Si–B alloys
Authors: SYPIEŃ A. , KUSIŃSKI J. 
Published: November 2006

SummaryThis article describes the results of investigations of the microstructure of failure surfaces and the mechanism of deformation of an amorphous Fe80Si11B9 alloy, nanocrystallized with the use of Nd:YAG pulsed laser heating. The research included ‘in situ’ tensile testing in a scanning electron microscope. Mechanical properties were also measured on an Instron‐type machine for the amorphous and nanocrystalline alloys. The mechanical tensile tests performed on the amorphous and nanocrystalline samples showed a ductile fracture surface with very high fracture stress. Detailed observations of the flow deformation and fractures revealed the relationship between the quenched‐in crystalline and mechanical behaviour.
Characterization of the near‐surface layers of carbon steels modified by interaction with intense pulsed plasma beams: scanning electron microscopy investigations
Authors: SARTOWSKA B. , PIEKOSZEWSKI J. , WALIŚ L. , STANISŁAWSKI J. , NOWICKI L. , RATAJCZAK R. 
Published: November 2006

SummaryModification of materials is a wide area in materials science, especially surface modification. To investigate the results of the modification process, treated and nontreated samples were compared. Intense plasma pulses of argon or nitrogen were used to irradiate the carbon steels. In all samples, the near‐surface layer was melted. Results of scanning electron microscopy investigations of the surface morphology and cross‐sections, as well as the results of tribological tests, are presented. The obtained results allowed us to draw conclusions about changes in material properties and to propose subsequent studies using other investigation techniques.
Transmission electron microscopy analysis of phase separation in GaInAsSb films grown on GaSb substrate
Authors: SZCZESZEK P. , AMARIEI A. , SCHÖNE J. , ZOULIS G. , VOUROUTZIS N. , POLYCHRONIADIS E. K. , STRÓŻ D. 
Published: November 2006

SummaryThe GaSb‐based quaternary alloys are a good choice for thermophotovoltaic applications. The thermophotovoltaic cell converts infrared radiation to electricity, using the same principles as photovoltaic devices. The aim of the present work was the microstructural study of such an alloy, namely Ga0.84In0.16As0.12Sb0.88. A thin film of the material was grown by metal organic vapour phase epitaxy on a (100)α→[111]B (α = 2°, 4°, 6°) GaSb substrate. The GaInAsSb alloy has an appropriate band gap, but suffers from a phase separation consisting of GaAs‐rich and InSb‐rich regions that is disadvantageous for cell efficiency. In this work, we employed a morphological approach to phase separation, with the use of conventional transmission electron microscopy and atomic force microscopy. The phase separation occurs in two different orientations: parallel to the growth direction (vertical) and inclined (lateral). After application of fast Fourier transformation filtering, the vertical periodicity was found to be λ = 5 nm for the pair (black and white) of layers independently of the cut‐off angle, whereas the lateral periodicity was related to it.
Investigation of Si–Au vicinal surfaces using scanning tunnelling microscopy and reflection high‐energy electron diffraction
Authors: MAZUREK P. , PAPROCKI K. , MITURA Z. 
Published: November 2006

SummarySilicon vicinal surfaces can be successfully used as substrates for the preparation of one‐dimensional nanostructures. The quality of the structures prepared may be controlled using scanning tunnelling microscopy, as shown in this work. Additionally, it is possible to obtain valuable information using reflection high‐energy electron diffraction. A typical way of employing reflection high‐energy electron diffraction is to observe patterns of scattered electrons on a screen. However, it is possible to obtain more detailed information on the arrangement of atoms at the surface if azimuthal plots are collected. Azimuthal plots are measured by recording the intensity of specularly reflected electrons during the rotation of the sample around an axis perpendicular to its surface. So far, only flat surfaces have been examined in such a way. In this work, it is shown that such data, containing interesting features, can also be collected for vicinal surfaces.
Yeast complementation reveals a role for an Arabidopsis thaliana late embryogenesis abundant (LEA)‐like protein in oxidative stress tolerance
Authors: Mowla Shaheen B. , Cuypers Ann , Driscoll Simon P. , Kiddle Guy , Thomson Jennifer , Foyer Christine H. , Theodoulou Frederica L. 
Published: November 2006

SummaryA functional cloning approach using the oxidant‐sensitive yeast mutant, Δyap1, was employed to identify plant genes involved in tolerance of oxidative stress. In this screen, we identified an Arabidopsis late embryogenesis‐abundant (LEA)‐like protein, AtLEA5, which increased the tolerance of Δyap1 cells to the oxidants H2O2, diamide, menadione and tert‐butyl hydroperoxide. Unlike canonical LEAs, AtLEA5 is constitutively expressed in roots and reproductive organs but not in seeds. In leaves of short‐day grown plants, AtLEA5 transcripts exhibited a diurnal pattern of regulation, where transcripts were repressed in the light and abundant in the dark. Expression of AtLEA5 in leaves was induced by oxidants, ABA and dehydration. Use of abi1‐1 (ABA‐insensitive) and aba1‐1 (ABA‐deficient) Arabidopsis mutants indicated that drought induction of AtLEA5 required ABA synthesis but was independent of the ABI1 gene product. Abscisic acid and H2O2 induction of AtLEA5 was also independent of the OXI1 protein kinase. Constitutive overexpression of AtLEA5 resulted in increased root growth and shoot biomass, both in optimal conditions and under H2O2 stress. However, in comparison with wild type, photosynthesis in overexpressing plants was more susceptible to drought. These features suggest that AtLEA5 has a unique function among LEA proteins in that it plays a specific role in protection against oxidative stress involving decreased photosynthesis. This protein functions as part of a complex network of defences that contribute to robustness of plants under stress by minimizing the negative effects of oxidation.
RNAi‐induced silencing of gene expression in strawberry fruit (Fragaria × ananassa) by agroinfiltration: a rapid assay for gene function analysis
Authors: Hoffmann Thomas , Kalinowski Gregor , Schwab Wilfried 
Published: November 2006

SummaryIntron‐containing constructs encoding self‐complementary ‘hairpin’ RNA (ihpRNA) have the potential to efficiently silence genes in a range of plant species. In this study we demonstrate the silencing of a ripening‐related chalcone synthase (CHS) gene in strawberry fruits (Fragaria × ananassa cv. Elsanta) by a construct (ihpRNA) containing the partial sense and corresponding antisense sequences of CHS separated by an intron obtained from a F. × ananassa quinone oxidoreductase gene. An Agrobacterium strain carrying a T‐DNA expressing the ihpRNA transgene was injected with a syringe into the receptacles of growing fruits still attached to the plant about 14 days after pollination. As a consequence of the reduced levels of CHS mRNA and enzymatic CHS activity, the levels of anthocyanins were downregulated and precursors of the flavonoid pathway were shunted to the phenylpropanoid pathway leading to a large increases in levels of (hydroxy) cinnamoyl glucose esters. We anticipate that this technique in combination with metabolite profiling analysis will be useful for studying the function of unknown genes during the development and ripening of strawberry fruit.
Hydrogen peroxide, nitric oxide and cytosolic ascorbate peroxidase at the crossroad between defence and cell death
Authors: De Pinto Maria Concetta , Paradiso Annalisa , Leonetti Paola , De Gara Laura 
Published: November 2006

SummaryAn increase in the production of reactive oxygen species (ROS) is a typical event occurring during different stress conditions and activating conflicting responses in plants. In order to investigate the relevance of different timing and amounts of ROS production, tobacco (Nicotiana tabacum) Bright Yellow‐2 (TBY‐2) cells were incubated with different amounts of glucose plus glucose oxidase, for generating H2O2during time, or directly with known amounts of H2O2. Data presented here indicate that, in TBY‐2 cells, a difference in H2O2level is a critical point for shifting metabolic responses towards strengthening of antioxidant defences, or their depletion with consequent cell death. Timing of ROS production is also critical because it can determine programmed cell death (PCD) or necrosis. Depending on the different kinds of activated cell death, ascorbate (ASC) and glutathione (GSH) pools are altered differently. Moreover, an H2O2‐dependent activation of nitric oxide synthesis is triggered only in the conditions inducing PCD. Ascorbate peroxidase (APX) has been analysed under different conditions of H2O2generation. Under a threshold value of H2O2overproduction, a transient increase in APX occurs, whereas under conditions inducing cell necrosis, the activity of APX decreases in proportion to cell death without any evident alteration in APX gene expression. Under conditions triggering PCD, the suppression of APX involves both gene expression and alteration of the kinetic characteristics of the enzyme. The changes in ASC, GSH and APX are involved in the signalling pathway leading to PCD, probably contributing to guaranteeing the cellular redox conditions required for successful PCD.