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Historically, men have dominated the field of behavior analysis; however, recent trends have indicated increased participation by women. As a result of these recent changes to the field of behavior analysis, the inaugural Women in Behavior Analysis Conference (WIBA) was hosted in 2017. WIBA was initially established to highlight the accomplishments of women in the field of behavior analysis, to provide opportunities for early career behavior analysts to obtain mentorship, and to encourage meaningful discourse about gender issues in the field. Since the inaugural conference, WIBA has attempted to establish a platform for promoting gender equality but most recently has incorporated efforts related to the needs surrounding social justice and inclusiveness in the field of behavior analysis. The goal of this paper is to provide an overview of the WIBA conference. The history of WIBA is discussed, including the impetus for establishing the conference. This paper highlights existing issues on gender equality in the field of behavior analysis and the larger community, serves to demonstrate how WIBA is part of the solution, and shares accomplishments to date. Furthermore, future directions and goals are presented.

Summary In pressure predictions for early Stabroek exploration wells, minimum stress was calculated using the Terzaghi soil mechanics method (Matthews and Kelly, 1967) and a standard range of effective stress ratios according to Shmin=K0(Sv-Pp)+Pp, where Shmin is minimum stress, Sv is the overburden, PP is the pore fluid pressure and K0 is the effective stress ratio. These calculated profiles were compared to minimum stress estimates obtained from leak-off tests, pressure integrity tests, and lost return events. In several cases, the well data suggested significantly higher minimum stresses than predicted, with most tests in the deeper MTDs approaching the estimated overburden stress. To address the applicability of these estimates for minimum stress to future well planning, several interpreted mechanisms for these elevated stresses were proposed and investigated.

Vascular endothelial growth factor (VEGF) is thought to provide neuroprotection to the traumatically injured spinal cord. We examined whether supplementing the injured environment with VEGF(165) via direct intraspinal injection into the lesion epicenter during the acute phase of spinal cord injury (SCI) results in improved outcome. The effect of treatment was investigated using longitudinal multi-modal magnetic resonance imaging (MRI), neurobehavioral assays, and end-point immunohistochemistry. We observed on MRI that rats treated with VEGF(165) after SCI had increased tissue sparing compared to vehicle-treated animals at the earlier time points. However, these favorable effects were not maintained into the chronic phase. Histology revealed that VEGF(165) treatment resulted in increased oligodendrogenesis and/or white matter sparing, and therefore may eventually lead to improved functional outcome. The increase in spared tissue as demonstrated by MRI, coupled with the possible remyelination and increased neurosensory sensitivity, suggests that VEGF(165) treatment may play a role in promoting plasticity in the sensory pathways following SCI. However, VEGF-treated animals also demonstrated an increased incidence of persistent allodynia, as indicated on the von Frey filament test.

Vascular endothelial growth factor (VEGF)-A mRNA was previously identified as one of the significantly upregulated transcripts in spinal cord injured tissue from adult rats that developed allodynia. To characterize the role of VEGF-A in the development of pain in spinal cord injury (SCI), we analyzed mechanical allodynia in SCI rats that were treated with either vehicle, VEGF-A isoform 165 (VEGF(165)), or neutralizing VEGF(165)-specific antibody. We have observed that exogenous administration of VEGF(165) increased both the number of SCI rats that develop persistent mechanical allodynia, and the level of hypersensitivity to mechanical stimuli. Our analysis identified excessive and aberrant growth of myelinated axons in dorsal horns and dorsal columns of chronically injured spinal cords as possible mechanisms for both SCI pain and VEGF(165)-induced amplification of SCI pain, suggesting that elevated endogenous VEGF(165) may have a role in the development of allodynia after SCI. However, the neutralizing VEGF(165) antibody showed no effect on allodynia or axonal sprouting after SCI. It is possible that another endogenous VEGF isoform activates the same signaling pathway as the exogenously-administered 165 isoform and contributes to SCI pain. Our transcriptional analysis revealed that endogenous VEGF(188) is likely to be the isoform involved in the development of allodynia after SCI. To the best of our knowledge, this is the first study to suggest a possible link between VEGF, nonspecific sprouting of myelinated axons, and mechanical allodynia following SCI.

Summary Background Dog dander is an important cause of respiratory allergy but its content of allergenic components is still incompletely known. While Can f 1, 2, 3 and 5 have been studied in detail, only fragmentary information is available on the lipocalin Can f 4. Objective To purify, clone and characterize dog dander allergen Can f 4. Methods Can f 4 was purified from dog dander extract by size exclusion, ion exchange and reverse phase chromatography. A cDNA encoding Can f 4 was cloned and used to produce recombinant Can f 4 in Escherichia coli. A 23 kDa protein from cow dander, displaying cross-reactivity with Can f 4, was purified and identified by amino acid sequencing and mass spectrometry. IgE antibody binding to dog and cow dander extract and to individual dog allergens among 37 dog allergic subjects and 44 pollen allergic controls was studied using ImmunoCAP. Results A dog genome segment containing the Can f 4 gene was bioinformatically identified and enabled the cloning of Can f 4 cDNA. Recombinant Can f 4 displayed close immunological and biochemical similarity to purified natural Can f 4 and bound IgE antibodies from 13/37 (35%) sera of dog allergic subjects. Can f 4 reactive sera showed IgE binding to a 23 kDa protein present in cow dander extract, related to a family of odorant-binding proteins. The dog and cow proteins shared 37% sequence identity and their cross-reactivity was demonstrated by IgE inhibition experiments. Conclusion Recombinant Can f 4 brings the panel of available dog allergens closer to completion and will be important in component-resolved diagnostics in allergy to animal epithelial allergens. Cite this as: L. Mattsson, T. Lundgren, P. Olsson, M. Sundberg and J. Lidholm, Clinical & Experimental Allergy, 2010 (40) 1276–1287.

After a primary traumatic injury, spinal cord tissue undergoes a series of pathobiological changes, including compromised blood-spinal cord barrier (BSCB) integrity. These vascular changes occur over both time and space. In an experimental model of spinal cord injury (SCI), longitudinal dynamic contrast-enhanced MRI (DCE-MRI) studies were performed up to 56 days after SCI to quantify spatial and temporal changes in the BSCB permeability in tissue that did not show any visible enhancement on the post-contrast MRI (non-enhancing tissue). DCE-MRI data were analyzed using a two-compartment pharmacokinetic model. These studies demonstrate gradual restoration of BSCB with post-SCI time. However, on the basis of DCE-MRI, and confirmed by immunohistochemistry, the BSCB remained compromised even at 56 days after SCI. In addition, open-field locomotion was evaluated using the 21-point Basso-Beattie-Bresnahan scale. A significant correlation between decreased BSCB permeability and improved locomotor recovery was observed.

Intestinal obstruction due to intussusception, although rare, is a complication that can cause small bowel obstruction after Roux-en-Y gastric bypass. Possible causes include disordered intestinal motility, the presence of staple lines and other lead points in the intestinal wall, and the anatomic peculiarities of the enteroenterostomy. In the case of antegrade intussusception, the lead point is usually identifiable and can involve either limb. Retrograde intussusception is more common but usually has a featureless entry point beginning a few inches below the intestinal anastomosis, with the intussusceptum traversing the enteroenterostomy into either the biliary or Roux limb. Abdominal computed tomography scan is necessary for diagnosis, and early exploration is recommended to avoid ischemia and bowel resection.

Aluminium containing heat-resistant silicides and ternary carbides (Maxthal ® ), have been evaluated in terms of their high temperature behaviour in various atmospheres including vacuum. The novelty of these materials is in their ability to form a stable and adherent protective alumina scale at low partial pressures of oxygen as well as in air. Recently developed heating elements, for oxidising and reducing atmospheres, made of molybdenum aluminosilicide (Kanthal Super ER) have been evaluated by thermogravimetric analysis (TGA) studies in air and other atmospheres. The performance up to 1575 °C has been evaluated at vacuum levels down to 10 −4 mbar. In addition to its remarkable thermal shock resistance, damage tolerance and machinability, Ti 2 AlC (Maxthal ® ) showed a parabolic and stable oxide growth rate up to 1400 °C in air. Cyclic testing confirmed that the oxide layer is adherent to the bulk. It has been concluded that both Maxthal ® and Kanthal Super ER are capable of operating in air, up to 1400 and 1575 °C, respectively.

The C40 Mo(Si0.75Al0.25)2 and Mo(Si0.75Al0.25)2/SiC materials containing micro-, nano-scale structure and Mo/Mo5Si3 phases have been prepared by spark plasma sintering (SPS) of mechanically alloyed (MA) powders. Sintered composites have hardness around 14 GPa. The 1.84 MPa m1/2 toughness of C40 Mo(Si,Al)2 can be 30% improved by addition of 20 vol.% SiC.

The inflammatory bowel diseases (IBD) ulcerative colitis (UC) and Crohn disease (CD) affect a person's health-related quality of life (HRQOL). IBD patients report high levels of anxiety, which correlates with the degree of perceived dissatisfaction with the information on disease-related themes provided in routine health care. The aim of this study was to evaluate changes in anxiety after participation in a group-based educational intervention for IBD patients screened for high anxiety.The programme consisted of 8 sessions, and 49 patients participated. Anxiety was assessed using the Hospital Anxiety and Depression (HAD) Scale at baseline and 6 months after intervention. HRQOL was assessed with the Inflammatory Bowel Disease Questionnaire (IBDQ) and the SF-36 health survey. Participant satisfaction with education was measured using a study-specific questionnaire.No significant change on the HAD anxiety score was found at the 6-month follow-up for those who participated in the education programme despite the fact that the participants reported they had gained better knowledge of disease-related items. Furthermore, there were no significant changes over time regarding bowel symptoms, systemic symptoms, emotional functioning and social functioning of the IBDQ or generic HRQOL (SF-36).IBD patients with a high anxiety level reported improved satisfaction with information about disease-related items, but did not indicate any benefits in terms of reduced anxiety or improved HRQOL after participating in the education programme, not at least in the short-term perspective. In this selected group of patients, psychosocial problems other than disease-related concerns were found that warrant other approaches.

Spinal cord injury (SCI) results in immediate disruption of the spinal vascular network, triggering an ischemic environment and initiating secondary degeneration. Promoting angiogenesis and vascular stability through the induction of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1), respectively, provides a possible therapeutic approach in treating SCI. We examined whether supplementing the injured environment with these two factors, which are significantly reduced following injury, has an effect on lesion size and functional outcome. Sustained delivery of both VEGF(165) and Ang-1 was realized using viral vectors based on the adeno-associated virus (AAV), which were injected directly into the lesion epicenter immediately after injury. Our results indicate that the combined treatment with VEGF and Ang-1 resulted in both reduced hyperintense lesion volume and vascular stabilization, as determined by magnetic resonance imaging (MRI). Western blot analysis indicated that the viral vector expression was maintained into the chronic phase of injury, and that the use of the AAV vectors did not exacerbate infiltration of microglia into the lesion epicenter. The combined treatment with AAV-VEGF and AAV-Ang-1 improved locomotor recovery in the chronic phase of injury. These results indicate that combining angiogenesis with vascular stabilization may have potential therapeutic applications following SCI.

This article contributes to the characterization of low temperature oxidation behavior of a MoSi 2 composite for heating elements. The initial silica growth kinetics, its oxygen partial pressure dependence, MoO 3 evaporation rate and the microstructural evolution during oxidation have been examined. The oxidation exposure was carried out in the temperature range from 673 to 873 K in flowing oxygen or mixtures of argon and oxygen gases. The major analytical techniques include X-ray powder diffractometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy, scanning electron microscopy and BET method. It is shown that silica growth rate at 773 K decreases with time and the square of silica thickness increases with the oxygen partial pressure. Evaporation rate of MoO 3 powder increases exponentially with increasing temperature in the range from 823 to 973 K in flowing O 2 . Accumulation of Mo-rich phase, presumably MoO 3 , in the thick silica layer was readily seen at 723 K.

A new type of twinning occurring in intergrowth tungsten bronzes (ITB) is described, revealed by high-resolution electron microscopy. Across the twin boundary the two structure elements of hexagonal tungsten bronze- and tetragonally distorted ReO3-types are interchanged and grow in strict geometrical relationship to each other. The structure is thus `inverted' and in the general case the two `twin' parts represent different members of the structure family. Some members remain invariant upon inversion, however. This defect is most often seen as ribbons in an ITB matrix in Mo-doped samples Cs x Mo y Wl−y O3, which require a lower synthesis temperature than pure tungsten bronzes. They may be frozen-in stages of a slow ordering process. A similar type of twinning might be found in other intergrowth structures.

The structures of two high-pressure tungsten oxides, previously studied by high-resolution electron microscopy, were confirmed by Rietveld refinement based on X-ray powder diffraction data. The phases have identical stoichiometry, W3O8, and extremely narrow 00l reflections in common. The microstructure of the dominant phase was investigated by means of X-ray powder diffraction pattern decomposition. A Williamson–Hall plot revealed that all lines, except the 00l reflections, were broadened solely due to the crystallite size effect. A cylindrical model is used to describe the average form of the coherently diffracting domains. The height of the cylinder, whose axis is colinear with the crystallographic c parameter of both phases, is considered “infinite,” and the average diameter of the cylinder model is 655(22) Å. A quantitative confirmation is obtained from electron microscopy.

It has been shown that chronic consumption of ethanol can impair myocardial function and result in morphological changes of the heart. The purpose of this work was to evaluate relations between changes in energy metabolism and changes of cell morphology.Long-term effects of moderate ethanol consumption on the heart were examined in isolated cardiomyocytes from rats fed a pellet with low-protein content for 6 months. Digitonin treatment of the cardiomyocytes was used to separate mitochondrial and cytosolic fractions.A greater fraction of contracted myocytes was isolated from ethanol- and glucose-treated rats, than from rats fed only glucose and/or water as liquid supplement. There were changes of the ultrastructure of myocytes from ethanol and glucose-treated rats, which included mitochondrial degeneration, accumulation of fat droplets and depletion of the glycogen content. An elevated cytosolic level of nucleotides (ATP, ADP and NAD) and disappearance of magnesium from the mitochondrial fraction were observed in myocytes from rats fed ethanol and glucose. The release of adenosine was also found to be inhibited in these cells.Our results show that moderate ethanol consumption by rats during protein-restricted conditions produces subclinical changes of cardiomyocyte ultrastructure and alteration of cell morphology. Furthermore, the results indicate that changes of the energy homeostasis in myocytes and inhibition of sarcolemmal adenosine transport are early events that appear to precede the histological alterations.

A high-pressure modification of tungsten dioxide (hp-WO2) was synthesized at 80 kbar and 1120 K. The structure was determined from X-ray powder diffraction data: hp-WO2, M = 215.85, space group Pnma, a = 9.7164(3) Å, b = 8.4380(3) Å, c = 4.7564(2) Å, Z = 12, D x = 11.03 g cm−3, Rwp = 0.12 and RB = 0.078 from Rietveld refinement. Although the heavy atom structure may be reasonably well described in space group Cmcm, the total structure can only be described in Pnma. The important information contained in non observable and very weak reflections is discussed. In the hp-WO2, modification the W atoms occupy half of the octahedral interstices of an hcp arrangement of oxygen atoms. It can be described as a distorted rutile structure which is twinned at the unit cell level. An essential feature is that groups of three edge-sharing WO6 octahedra are formed at twin planes. The relation between the ambient-pressure (distorted rutile type) and the high pressure modifications is discussed.

The ontogeny of staminate tassels and pistillate ears in the maize mutant Fascicled ear was examined using scanning electron microscopy. The normal pattern of inflorescence development is perturbed by the Fascicled ear mutation at the transition stage. The Fascicled ear mutation promotes the development of an abnormal transition stage axis that is both shorter and broader than the wild type. The inflorescence apical meristem then undergoes a bifurcation, and two inflorescence axes arise in place of a single axis. Each derived inflorescence apical meristem may undergo a similar perturbation sequence. This expression of the Fascicled ear mutation may be repeated one to several times, which leads to the development of a fascicled pistillate inflorescence and a fascicled central spike in the staminate inflorescence. The apical meristems of some tassel branches are also bifurcated. Subsequent organogenesis during paired-spikelet and floral development in Fascicled ear plants follows the pattern of normal maize. However, triplet spikelets are occasionally observed. The organogenic disruption by the Fascicled ear mutation that we describe will aid genetic and molecular analysis on the regulation of inflorescence development in maize and other members of the genus Zea.

Comprehensive in vivo longitudinal studies that include multi-modal magnetic resonance imaging (MRI) and a battery of behavioral assays to assess functional outcome were performed at multiple time points up to 56 days post-traumatic spinal cord injury (SCI) in rodents. The MRI studies included high-resolution structural imaging for lesion volumetry, and diffusion tensor imaging (DTI) for probing the white matter integrity. The behavioral assays included open-field locomotion, grid walking, inclined plane, computerized activity box performance, and von Frey filament tests. Additionally, end-point histology was assessed for correlation with both the MRI and behavioral data. The temporal patterns of the lesions were documented on structural MRI. DTI studies showed significant changes in white matter that is proximal to the injury epicenter and persisted to day 56. White matter in regions up to 1 cm away from the injury epicenter that appeared normal on conventional MRI also exhibited changes that were indicative of tissue damage, suggesting that DTI is a more sensitive measure of the evolving injury. Correlations between DTI and histology after SCI could not be firmly established, suggesting that injury causes complex pathological changes in multiple tissue components that affect the DTI measures. Histological evidence confirmed a significant decrease in myelin and oligodendrocyte presence 56 days post-SCI. Multiple assays to evaluate aspects of functional recovery correlated with histology and DTI measures, suggesting that damage to specific white matter tracts can be assessed and tracked longitudinally after SCI.

Dog dander is an important cause of respiratory allergy but its content of allergenic components is still incompletely known. While Can f 1, 2, 3 and 5 have been studied in detail, only fragmentary information is available on the lipocalin Can f 4.To purify, clone and characterize dog dander allergen Can f 4.Can f 4 was purified from dog dander extract by size exclusion, ion exchange and reverse phase chromatography. A cDNA encoding Can f 4 was cloned and used to produce recombinant Can f 4 in Escherichia coli. A 23 kDa protein from cow dander, displaying cross-reactivity with Can f 4, was purified and identified by amino acid sequencing and mass spectrometry. IgE antibody binding to dog and cow dander extract and to individual dog allergens among 37 dog allergic subjects and 44 pollen allergic controls was studied using ImmunoCAP.A dog genome segment containing the Can f 4 gene was bioinformatically identified and enabled the cloning of Can f 4 cDNA. Recombinant Can f 4 displayed close immunological and biochemical similarity to purified natural Can f 4 and bound IgE antibodies from 13/37 (35%) sera of dog allergic subjects. Can f 4 reactive sera showed IgE binding to a 23 kDa protein present in cow dander extract, related to a family of odorant-binding proteins. The dog and cow proteins shared 37% sequence identity and their cross-reactivity was demonstrated by IgE inhibition experiments.Recombinant Can f 4 brings the panel of available dog allergens closer to completion and will be important in component-resolved diagnostics in allergy to animal epithelial allergens.

Compromised blood-spinal cord barrier (BSCB) is a factor in the outcome following traumatic spinal cord injury (SCI). Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis and vascular permeability. The role of VEGF in SCI is controversial. Relatively little is known about the spatial and temporal changes in the BSCB permeability following administration of VEGF in experimental SCI. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) studies were performed to noninvasively follow spatial and temporal changes in the BSCB permeability following acute administration of VEGF in experimental SCI over a post-injury period of 56 days. The DCE-MRI data was analyzed using a two-compartment pharmacokinetic model. Animals were assessed for open field locomotion using the Basso-Beattie-Bresnahan score. These studies demonstrate that the BSCB permeability was greater at all time points in the VEGF-treated animals compared to saline controls, most significantly in the epicenter region of injury. Although a significant temporal reduction in the BSCB permeability was observed in the VEGF-treated animals, BSCB permeability remained elevated even during the chronic phase. VEGF treatment resulted in earlier improvement in locomotor ability during the chronic phase of SCI. This study suggests a beneficial role of acutely administered VEGF in hastening neurobehavioral recovery after SCI.

Steel reinforced concrete is a widely used construction material. It is often the material of choice in bridges, parking garages, and marine structures because of its good durability and resistance to corrosion. However, over time, even well designed concrete is susceptible to chloride intrusion from deicing or marine salts or both, resulting in corrosion of embedded steel. By the time corrosion of steel in concrete is readily noticeable, major repairs are often required. A nondestructive means of determining the corrosion rate of inaccessible steel is thus needed. Electrochemical techniques such as polarization resistance are useful, however resistivities of concrete range from 1000 to greater than 30 000 ohm-cm. Furthermore, reference electrodes are usually greater than 25 mm from the working electrode (rebars). Thus, large ohmic electrolyte resistance is present, even at the low current densities associated with steel in concrete, and must be accounted for to accurately measure corrosion rates. In this paper we compare the use of current interruption correction for ohmic resistance to an electrochemical impedance measurement at 20 KHz. In general, we find a good correlation between the two techniques, and demonstrate that substantial ohmic resistances are present.

Rectifying contacts between poly(3-hexylthiophene) and Indium-Tin oxide or Aluminum have been studied by means of current-voltage measurements and capacitance-voltage measurements. The results show that the current transport through these contacts is not well described by conventional thermionic emission theory. Furthermore, the dopant distribution is not homogeneous in the polymer. Dopants accumulate near the polymer/metal interface. This accumulation can be enhanced by means of an electric field applied across the structure.

Following the primary traumatic injury, spinal cord tissue undergoes a series of pathobiological changes, including compromised blood-spinal cord-barrier (BSCB) integrity. These vascular changes occur over both time and space. In an experimental model of spinal cord injury (SCI), longitudinal dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)studies were performed up to 56 days post-SCI to quantify spatial and temporal changes in the BSCB permeability in tissue that did not show any visible enhancement on the post-contrast MRI(non-enhancing tissue). DCE-MRI data was analyzed using a two-compartment pharmacokinetic model. These studies demonstrate gradual restoration of BSCB with post-SCI time. But, based on DCE-MRI, and confirmed by immunohistochemistry, the BSCB remained compromised even at 56 days post-SCI. In addition, open-field locomotion was evaluated using the 21 point Basso-Beattie-Bresnahan scale. A significant correlation between decreased BSCB permeability and improved locomotor recovery was observed.

Two previously purified esterases of Trichoderma reesei were used to study the deacetylation of polymeric, oligomeric and dimeric acetylated xylan fragments. For the first time nearly complete enzymatic deacetylation of polymeric xylan with purified acetyl xylan esterase was demonstrated, resulting in precipitation of the remaining polymer structure. The esterases had very different substrate specifities, one having a preference for high molecular weight substrates and the other showing high activity only towards acetyl xylobiose. The latter enzyme was also regioselective, cleaving off the acetyl substituent only from the C-3 position of the xylopyranose ring. The highest xylose yield from acetylated xylan was obtained by the synergistic action of xylanase, \-xylosidase and acetyl xylan esterase.

The regional pattern of insulin-dependent diabetes mellitus (IDDM) incidence among children in Finland was analysed applying several methods attempting to describe the geographical variation in occurrence of IDDM. From 1987 to 1991 the number of newly diagnosed cases aged 14 years or less at diagnosis was 1728. The incidence, the incidence rate ratio and the Bayes relative risk (RR) for IDDM were calculated by municipality, by functional area (an urban centre with a subordinated surrounding area) and by area with a population of equal size at risk employing the Geographical Information Systems. The association of IDDM incidence with the degree of urbanization was assessed using the population density as a criterion for the degree of urbanization. The overall mean of the IDDM incidence was 35 per 100000 persons per year. Between municipalities the incidence varied from 4 to 245 per 100000 persons per year, whereas a clear regional pattern was seen among the functional areas and the incidence varied from 26 to 43 per 100000 persons per year. The RR for IDDM among the municipalities ranged from 0.82 to 1.34 and from 0.73 to 1.27 among the functional areas. The incidence determined in four zones with the same size of population was the highest in the middle part of the country. There was a strong inverse correlation between population density and the incidence of IDDM and this also applied to the relationship between child population density and incidence.

Rectifying contacts between aluminum, indium, or titanium and a solution and melt processable conducting polymer, poly(3‐octylthiophene) have been formed by melt processing. The contacts are formed by heating a metal/polymer/metal structure to the melting point of the polymer and then pressing the metals to the melted polymer until adhesion is achieved, whereupon the whole structure is cooled to room temperature. Comparison of the current‐voltage and capacitance‐voltage characteristics of a melt processed device and a device manufactured by metal sputtering shows that no significant differences exist between these structures.

The defects in the zinc selenide crystals with zinc blende structure grown from the melt by the Bridgman method under argon pressure are examined by electron microscopy. The microscopical observations are performed using high voltage, high resolution, and conventional microscopes. Results of investigations of twins, stacking faults, dislocations, precipitates, and pores in ZnSe crystals are presented and discussed. Mittels Elektronenmikroskopie werden die Defekte in Zinkselenidkristallen mit Zinkbleudestruktur, die mit der Bridgmanmethode unter Argondruck aus der Schmelze gezogen werden, untersucht. Die mikroskopischen Beobachtungen werden mittels Hochspannungs-, Hochauflosungsund konventioneller Mikroskopie durchgefuhrt. Ergebnisse von Untersuchungen an Zwillingen, Stapelfehlern, Versetzungen, Prazipitaten und Poren in ZnSe-Kristallen werden mitgeteilt und diskutiert.

K 2 Nb 10 W 7 O 47 cristallise dans le systeme monoclinique avec le groupe d'espace P2/m. La structure a ete confirmee par calculs d'images de simulation et diffraction RX. Le squelette polyedrique se compose de colonnes d'octaedres et de pentaedres qui forment des tunnels de quatre, cinq et six cotes. La structure a les caracteristiques des structures types W 18 O 49 et bronze tungstene quadratique

The influence of alloying with aluminium, manganese, silicon, tin and iron on the wear properties of special brass has been investigated, mainly in the region of severe wear. The surface layer developed during dry sliding against steel was characterized with respect to structure, composition and hardness. Irrespective of original structure and composition, a superficial extremely fine-grained layer of α phase is formed. Oxidation of β-phase-promoting elements causes the transition to the α phase. The grain size of this α phase is approximately 0.1 μm; the layer is much harder than the bulk material and has very special wear properties. Beneath there is a second layer mainly consisting of β phase with a fine grain size (2–5 μm) and an increased hardness relative to the bulk material. Additions of solution- and precipitation-hardening elements like tin, aluminium, manganese, silicon or iron have a positive effect on the resistance against wear, both in the mild and the severe regime. A comparison is made with a service-tested synchronizing ring with respect to the wear mechanisms and the resulting surface layer.

Large crystals of WO3 have been reduced to a composition of approximately WO2.91 at 3 different temperatures, 950, 1000, and 1070°C. After reduction the crystals were examined by optical microscopy and transmission electron microscopy. The crystals were faulted in a variety of ways and rarely perfectly ordered. Large crystals heated at 1070°C supported oxygen loss by formation of {103} CS planes while crystals heated at 950°C contained {102} CS planes. At 1000°C {102} and {103} CS planes coexisted. It was found that the way in which the WO3 structure accommodated oxygen loss was a function of composition and of temperature. In all experiments, some vapour transport also took place, resulting in the growth of needle shaped crystals. These were always members of the WxO3n−2 homologous series of oxides, and contained {103} CS planes, irrespective of the formation temperature.

The reduction of oxygen on rotating disk glassy carbon electrodes was studied in 0.1M HCl. Reproducible single waves with constant limiting currents over a potential range of 0.5V were obtained after the samples were electrochemically treated: anodic polarization at 2.0V vs. SCE and subsequent cathodic reduction. The number of electrons transferred in the oxygen reduction reaction was calculated to be 2.3. The surface of the glassy carbon was examined by XPS at different stages of the electrochemical treatment. After the anodic treatment, the ratio of oxidized carbon vs. graphitic carbon was higher than 1. The predominant oxygen species were carbonyl groups. Following reduction, the surface had an oxidized vs. graphitic carbon ratio below 0.5 with the oxygen distributed between phenolic and carboxylic groups. The role of the chloride ion in the formation of the carbonyl groups is discussed.