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Atraumatic splenic rupture is a complex surgical pathology owing to its rarity, non-specificity of symptoms and gravity of possible outcomes. This case outlines the investigation and management of a patient with atraumatic splenic rupture secondary to undiagnosed hairy cell leukaemia. While the patient was initially managed conservatively, they went on to have a splenectomy owing to ongoing transfusion requirements. A review of the literature has also been performed and presented to highlight the potential causes of atraumatic splenic rupture and the various options for confirming diagnosis and definitive management. [ABSTRACT FROM AUTHOR]

Iatrogenic diaphragmatic herniation is rare. This case is an example of herniation of the liver into the pericardial space post-transdiaphragmatic pericardial window formation for recurrent pericarditis. This case highlights that transdiaphragmatic herniation of intra-abdominal organs should be considered in patients presenting with gastrointestinal or cardiorespiratory symptoms with history of iatrogenic diaphragmatic defect. [ABSTRACT FROM AUTHOR]

The ability to manipulate rheological and electrical properties of colloidal carbon black gels makes them attractive in composites for energy applications such as batteries and fuel cells, where they conduct electricity and prevent sedimentation of 'granular' active components. While it is commonly assumed that granular fillers have a simple additive effect on the composite properties, new phenomena can emerge unexpectedly, with some composites exhibiting a unique rheological bi-stability between high-yield-stress and low-yield-stress states. Here we report such bi-stability in suspensions of non-Brownian graphite and colloidal carbon black in oil, a model system to mimic composite suspensions for energy applications. Steady shear below a critical stress elicits a transition to a persistent mechanically weak and poorly conducting state, which must be 'rejuvenated' using high-stress shear to recover a stronger, high-conductivity state. Our findings highlight the highly tunable nature of binary granular/gel composite suspensions and present new possibilities for optimising mixing and processing conditions for Li-ion battery slurries. [ABSTRACT FROM AUTHOR]

The p-ketoimine HC[MeC(O)][MeC(NHt-Bu)] (1H) (Me = methyl) was used as a ligand in the synthesis of organo-aluminium and gallium compounds. With Al, the NH functionality was deprotonated to form the N,O-chelating β-ketoiminate ligand in Al{HC[MeC(O)][MeC(Nt-Bu)]}Me[sub 2] (3) (t-Bu = tertiary butyl), whereas the neutral form coordinated to trimethylgallium via the oxygen atom to form the adduct GaMe[sub 3].{HC[MeC(O)][MeC(NHt-Bu)]} (4). Reaction of 1H with Ar†NH[sub 2] (Ar†- 2-t-BuC6H4) afforded the new N-aryl β-ketoimine HC[MeC(O)][MeC(NHAr†)] (2H), which reacted with Pd(OAc)[sub 2] (OAc = acetate = CH[sub 3]CO[sub 2][sup -]) to afford the heteroleptic dimer {Pd[HC(MeC(O))(MeC (NAr†))](μ-OAc)}[sub 2] ([5][sub 2]). The homoleptic bis(β-ketoiminate) Pd{HC[MeC(O)][MeC(NAr†)]}[sub 2] (6) was isolated as a minor product of this reaction. The crystal structures of compounds 3, 4, [5][sub 2], and 6 are reported. [ABSTRACT FROM AUTHOR]

Many global and national conservation initiatives have objectives relating to reducing or reversing the rate of biodiversity decline but few have specific targets. In 2015, the Australian Government implemented a Threatened Species Strategy that aimed to improve the population trajectory of a set of 71 species (20 mammals, 21 birds and 30 plants) by 2020, relative to the trajectory before 2015. To assess the extent to which this objective had been achieved, and because there was no or limited monitoring for many of the species, we used structured expert elicitation to estimate population size for every species at 2005, 2015, 2020, and predict population size at 2025, 2035 and 2045. Elicitation was informed by a consistent collation of information for every species, including on threats, management actions, and available monitoring. Experts estimated that the population trajectories of 15 species had improved significantly (at p < 0.05, or 24 species at p < 0.1) over the period 2015–20 (the period coinciding with priority attention under the Threatened Species Strategy) relative to 2005–15, and 13 species had deteriorated significantly (at p < 0.05, or 15 at p < 0.1). The lack of recovery for a substantial component of the set of priority species was likely due to the short (5-year) period considered over which deeply ingrained threats may not be ameliorated, the impacts of drought and wildfire in this period, and the relative ineffectiveness of some management actions to mitigate the most important threats. Assessment of population trajectories was least confident and most inconsistent among experts for species with least monitoring effort. Experts predicted ongoing future declines with cessation of conservation management actions, but some longer-term recovery for most plant and mammal species with ongoing conservation management. Elicitation helped provide a consistent approach towards inferring population trends, but more ideal would be to monitor populations for all threatened species. [ABSTRACT FROM AUTHOR]

Reilly, T., Fraser, H. M., Fryer, R. J., Clarke, J., and Greenstreet, S. P. R. 2014. Interpreting variation in fish-based food web indicators: the importance of “bottom-up limitation” and “top-down control” processes. – ICES Journal of Marine Science, 71: 406–416.Proposed indicators for the Marine Strategy Framework Directive (MSFD) food webs Descriptor focus on structural elements of food webs, and in particular on the abundance and productivity of top predators. However, the inferences that can be drawn from such indicators depend on whether or not the predators are “bottom-up limited” by the availability of their prey. Many seabird populations appear to be “bottom-up limited” so that variation in their reproductive success and/or abundance reflects changes in lower trophic levels. Here we find that gadoid fish predators off the Firth of Forth, southeast Scotland, do not appear to be “bottom-up limited” by the biomass of their main prey, 0-group sandeels; gadoid biomass and feeding performance was independent of sandeel biomass. Variability in food web indicators based on these gadoid predators seems to impart little insight into underlying processes occurring at lower trophic levels in the local food web. The implications of this in terms of how the currently proposed MSFD food web indicators should be used and interpreted are considered, and the ramifications in terms of setting targets representing good environmental status for both fish and seabird communities are discussed. [ABSTRACT FROM PUBLISHER]

We present near-infrared spectroscopic observations of 19 molecular clouds made using the AKARI satellite, and the data reduction pipeline written to analyze those observations. The 2.5-5 μm spectra of 30 objects—22 field stars behind quiescent molecular clouds and 8 low-mass young stellar objects in cores—were successfully extracted using the pipeline. Those spectra are further analyzed to calculate the column densities of key solid phase molecular species, including H2O, CO2, CO, and OCN–. The profile of the H2O ice band is seen to vary across the objects observed and we suggest that the extended red wing may be an evolutionary indicator of both dust and ice mantle properties. The observation of 22 spectra with fluxes as low as < 5 mJy toward background stars, including 15 where the column densities of H2O, CO, and CO2 were calculated, provides valuable data that could help to benchmark the initial conditions in star-forming regions prior to the onset of star formation. [ABSTRACT FROM AUTHOR]

Although questions about why so many women 'love to love' and why some stay with abusive lovers may seem clichéd, they are questions over which many people still muse. Using a collage of ideas drawn from a wide range of sources, including 83 narrative feminist interviews that were conducted from 2000 to 2004, I respond to these questions, trying to show some of the inducements that are made to women to love others. The simulated diary entries of one (composite) woman suggest that as many women enter monogamous coupledom, there are unexpected (but all too common) problems of intimacy. [ABSTRACT FROM AUTHOR]

This article seeks to contribute to discussions about how narrative analysis might be undertaken. I do this by exploring one method of narrative approach to analyse personal stories. Before considering some of the issues associated with narrative research, I comment on the rise of the 'narrative moment'. I then provide ways to conceptualize narrative research. In the final part of the discussion, I discuss ways to conduct narrative research. In so doing, I provide concrete details about how personal stories might be analysed line by line. [ABSTRACT FROM AUTHOR]

Recent advances in manufacturing technology have led to the development of a new breed of advanced materials. These new materials are process dependent and would be difficult, if not impossible, to produce using conventional methods. Laser direct manufacturing (LDM) is a solid freeform fabrication process that enables the production of these advanced materials. LDM utilizes a high energy density heat source, powdered metal feedstock, and computer driven machine controls to produce bulk materials in near-net shape form. The combination of powdered metallurgy (P/M) and rapid solidification processing (RSP) allow bulk structures to be made with novel compositions and unique properties. In addition, near-net shape production eliminates the need for thermomechanical post-processing that can nullify some of the metallurgical advantages gained through RSP and P/M. These advantages have led to the development of alloys specifically tailored to the LDM process. This paper describes a dispersion hardened erbium-bearing titanium alloy developed to couple with the processing advantages found in the laser direct manufacturing process. [ABSTRACT FROM AUTHOR]

Abstract Interactions between interstitial impurities and dislocations in gamma-TiAl have been observed by transmission electron microscopy. Diffraction contrast images showed evidence of the decoration of ordinary dislocations with Burgers vectors ] b , given by b = 1 110 , present both in subgrain boundaries and isolated in the 2 grain interiors, by small precipitates. Electron-energy-loss spectroscopy indicated that these precipitates are enriched in oxygen with respect to the TiAl matrix and may have formed oxides. Based on the contrast exhibited by these decorated defects in suitable weak-beam images a maximum diameter of about 10 nm has been determined for these precipitates. Furthermore, a model for the nature of the interaction between interstitial solute atoms and dislocations in gamma-TiAl has been proposed. The implications of these findings for the mechanical behaviour of gamma-TiAl-based alloys have been discussed. [ABSTRACT FROM AUTHOR]

Planet formation is strongly influenced by the composition and distribution of volatiles within protoplanetary disks. With JWST, it is now possible to obtain direct observational constraints on disk ices, as recently demonstrated by the detection of ice absorption features toward the edge-on HH 48 NE disk as part of the Ice Age Early Release Science program. Here, we introduce a new radiative transfer modeling framework designed to retrieve the composition and mixing status of disk ices using their band profiles, and apply it to interpret the H2O, CO2, and CO ice bands observed toward the HH 48 NE disk. We show that the ices are largely present as mixtures, with strong evidence for CO trapping in both H2O and CO2 ice. The HH 48 NE disk ice composition (pure versus polar versus apolar fractions) is markedly different from earlier protostellar stages, implying thermal and/or chemical reprocessing during the formation or evolution of the disk. We infer low ice-phase C/O ratios around 0.1 throughout the disk, and also demonstrate that the mixing and entrapment of disk ices can dramatically affect the radial dependence of the C/O ratio. It is therefore imperative that realistic disk ice compositions are considered when comparing planetary compositions with potential formation scenarios, which will fortunately be possible for an increasing number of disks with JWST. [ABSTRACT FROM AUTHOR]

The document delves into genetic studies on Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) in various countries, including New Zealand, China, and Japan. It discusses the identification of genetic variants in MND-linked genes, ALS pathogenic genes in juvenile patients, and genes affecting age at onset in Japanese ALS patients. The text also covers genetic testing for ALS, the impact of genetic results on patients and families, and the development of educational resources on genetic counseling and testing for ALS. Additionally, it explores studies on SOD1 variants, the role of FUS in ALS pathogenesis, and the importance of collaborative efforts like Project MinE and the New York Genome Center ALS Consortium in advancing ALS research. [Extracted from the article]

It is shown that local tetragonal distortion in a Si Ge0.05Si0.95 strained-layered structure can be detected and quantified from analyses of the high-order Laue zone lines which are present in the bright-field disks of [001] convergent-beam electron diffraction patterns. The detection of a tetragonal distortion is based on symmetry arguments, whereas the quantification requires a detailed analysis which is based on computer simulated patterns, assuming a kinematical approximation of the scattering process and including surface relaxation. The result of this quantitative analysis is in good agreement with the tetragonal distortion which is predicted by isotropic elasticity theory. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented that discussed the role of randomised badger culling trial for the control of bovine tuberculosis in Great Britain.

The present paper reports on the electrochemical properties of a wide range of high entropy alloys (HEAs) in a 0.6 M NaCl solution. A consolidated treatise of the topic has to date been lacking, and the purpose of the work herein is to present a primitive galvanic series for numerous HEAs, along with a broad survey of results typifying their electrochemical characteristics, passivity and comparative electrochemistry. The results are coupled with microstructural characterisation. The range of potentials for HEAs is comparable to or nobler than austenitic stainless steel, with a number of HEAs displaying higher pitting potential (Epit) values than stainless steels, in spite of possessing heterogeneous microstructures. [ABSTRACT FROM AUTHOR]

Thoraco-abdominal aneurysms (TAAA) represents a particularly lethal vascular disease that without surgical repair carries a dismal prognosis. However, there is an inherent risk from surgical repair of spinal cord ischaemia that can result in paraplegia. One method of reducing this risk is cerebrospinal fluid (CSF) drainage. We believe that the CSF contains clinically significant biomarkers that can indicate impending spinal cord ischaemia. This work therefore presents a novel measurement method for proteins, namely albumin, as a precursor to further work in this area. The work uses an interdigitated electrode (IDE) sensor and shows that it is capable of detecting various concentrations of albumin (from 0 to 100 g/L) with a high degree of repeatability at 200 MHz (R = 0.991) and 4 GHz (R = 0.975). [ABSTRACT FROM AUTHOR]

We present an experimental instrument that performs laboratory-based gas-phase Terahertz Desorption Emission Spectroscopy (THz-DES) experiments in support of astrochemistry. The measurement system combines a terahertz heterodyne radiometer that uses room temperature semiconductor mixer diode technology previously developed for the purposes of Earth observation, with a high-vacuum desorption gas cell and high-speed digital sampling circuitry to enable high spectral and temporal resolution spectroscopy of molecular species with thermal discrimination. During use, molecules are condensed on to a liquid nitrogen cooled metal finger to emulate ice structures that may be present in space. Following deposition, thermal desorption is controlled and initiated by means of a heater and monitored via a temperature sensor. The 'rest frequency' spectral signatures of molecules released into the vacuum cell environment are detected by the heterodyne radiometer in real-time and characterized with high spectral resolution. To demonstrate the viability of the instrument, we have studied Nitrous Oxide (N2O). This molecule strongly emits within the terahertz (sub-millimetre wavelength) range and provide a suitable test gas and we compare the results obtained with more traditional techniques such as quadrupole mass spectrometry. The results obtained allow us to fully characterize the measurement method and we discuss its potential use as a laboratory tool in support of astrochemical observations of molecular species in the interstellar medium and the Solar System. [ABSTRACT FROM AUTHOR]

During β-processing of α/β and β titanium alloys, variant selection (VS) of grain boundary α (GBα) is one of the key factors in determining the final transformation texture and mechanical properties. It has been observed frequently that GBα prefers its 〈0 0 0 1〉α pole to be parallel to a common 〈1 1 0〉β pole of the two adjacent β grains and results in a micro-textured region across the grain boundary (GB) and, as a consequence, slip transmission may take place more easily across that GB. In order to investigate how such a special prior β GB contributes to VS of GBα, we develop a crystallographic model based on the Burgers orientation relationship (BOR) between GBα and one of the two β grains. The model predicts all possible special β grain boundaries at which GBα is able to maintain BOR with both β grains. A new measure for VS of GBα, (β Δ J β BOR), i.e., a measure of the deviation of the actual OR between the GBα and the non-Burgers grain from the BOR, is proposed. For the particular alloy chosen for experimental observations, Ti-5553, it is found that when the misorientation angle θ m of (β Δ J β BOR) (instead of the closeness between two closet {110} β poles between two β grains widely used in literature) is less than 15 °, misorientation between the two β grains dominates the VS of GBα and, in particular, the variant with minimum θ m is always selected for GBα. A possible effect due to grain boundary plane inclination on VS is also discussed. [ABSTRACT FROM AUTHOR]

We study the temperature dependence of the generation of terahertz (THz) waves by photomixing in GaAs based antennas, grown at low-temperatures. For excitation with 780 nm light, the generated photocurrent increases by 15%, if the temperature is increased from 18 °C to 60 °C, whereas the generated THz power increases by 28%. The results show that the operation of THz antennas is robust with respect to changes in the ambient temperature and thus support the possibility of robust, potentially mobile devices without the need for a careful temperature control of the antenna structure. [ABSTRACT FROM AUTHOR]

Halyomorpha halys has recently established in countries outside of its Asian area of origin. In the North Eastern USA, this pest causes severe economic loss in agricultural crops. Breeding populations have been confirmed in Switzerland and Canada; however, their pathways of entry and genetic diversity remain unknown. To determine invasion pathways and source population(s), the diversity of specimens from Asia, North America, and Europe was investigated. Genetic diversity in Asia was higher than that in the Canada and Switzerland. Although three haplotypes were detected among Canadian H. halys, one haplotype dominated. In contrast, two out of three haplotypes were found frequently among Swiss samples. Based on molecular data and interception records it appears likely that H. halys in Canada is derived from the movement of established US populations. Further, North American populations likely originated from the Hebei/Beijing regions of China. The area of origin of the Swiss samples remains unclear. Although the dominant haplotype in Switzerland was consistent with Asian samples collected in the Hebei and Beijing provinces, it was not the dominant haplotype in these regions and further sampling is necessary to its confirm the distribution and abundance in the area of origin. The remaining two haplotypes were unique to Switzerland and no matches were found among our Asian samples. Interestingly, no haplotypes were shared between the North American and Swiss samples, indicating that the two invasions were separate and distinct events and did not result from the movement of goods and materials between USA and Europe. [ABSTRACT FROM AUTHOR]

The article focuses on a study on the distribution of Zaprionus indianus, Drosophilidae, in southern Ontario and Quebec, as of January 2013. topics include the impact of Z. indianus on damages caused to rotting fruit, examination of Ontario specimens, which were collected by the Ontario Ministry of Agriculture and Food and Ministry of Rural Affairs, by the researchers M. Miller and S. A. Marshall and identification of Zaprionus indianus as the only member of Zaprionus in Canada.

Abstract: The tensile properties obtained using an electrothermal mechanical tester (ETMT) and sub-scale specimens have been rigorously evaluated by comparing the results with those obtained using ASTM Standards over a controlled range of microstructures and temperatures (up to 300°C) for both (α+β)- and β-processed Ti–6Al–4V. These comparisons of the ETMT results, including yield strength (YS), ultimate tensile strength (UTS), Young''s modulus (E), total elongation, and reduction in area, have been made for six different microstructures producing controlled variations in properties. It has been shown that the ETMT may be used to successfully measure yield and ultimate tensile strength for (α+β)-processed Ti alloys. [Copyright &y& Elsevier]

Abstract: Recent work on hydrogen isotope retention in tungsten has shown a substantial fraction of the retained hydrogen to be in the form of molecules. It can be expected that hydrogen permeating through a material such as tungsten, that has a very low solubility for hydrogen, would come out of solution and combine into molecules at voids located throughout the bulk. The purpose of this report is to determine the type of voids responsible for the molecular retention. High purity tungsten provided by Plansee Aktiengesellschaft was first polished, annealed at 1273K in vacuum for one hour, and then exposed to high fluxes and high fluences of deuterium in the PISCES facility. High resolution Transmission Electron Microscopy was then used to examine the samples for voids. The results of these experiments were used to interpret the expected behavior of tungsten to be used as the divertor of the ITER fusion device. [Copyright &y& Elsevier]

This article investigates the intra-granular precipitation of nanometer-scale α platelets in the β matrix of a complex quaternary β titanium alloy, Ti-35Nb-7Zr-5Ta (all in wt%), for orthopedic implant applications, during β-solutionizing/quenching/aging type heat-treatments. The role of metastable ω precipitates on the nucleation and growth of these α precipitates, has been specifically addressed by coupling transmission electron microscopy (TEM) and 3D atom probe (3DAP) tomography studies on this alloy. Athermal ω precipitates form in this alloy on quenching from above the β-transus temperature. On isothermal annealing at low temperatures (~400 °C), these ω precipitates coarsen, rejecting Zr into the adjacent β matrix as determined by 3DAP studies. Concurrently, the nucleation and growth of α precipitates is initiated at or near the ω/β interfaces, as determined by TEM studies. In addition to coherency strains induced by the ω precipitates, the local enrichment of Zr adjacent to these precipitates appears to play an important role in aiding the nucleation and growth of Zr-rich α precipitates in this alloy. [ABSTRACT FROM AUTHOR]

Background: We aim to assess whether social deprivation independently predicts case fatality after a stroke patient has been admitted to hospital, and to assess whether social deprivation affected duration of hospital stay. Methods: Cohort study in a tertiary teaching hospital included consecutive patients admitted to hospital within 48 h of their stroke between 1988 and 1994. Outcome measures were case fatality at 1 year and length of hospital stay. The socioeconomic category was derived from the postcode sector of residence for the patients (Carstairs index). Cause of death was determined by data linkage to the Registrar General data for Scotland. Results: 2,042 stroke patients were included. A significant age difference existed between the deprivation categories (76.0 ± 10.9 years in the affluent cohort vs. 71.4 ± 10.7 years in the deprived cohort). Smoking was more common in the deprived group. ECG findings and neurological score on admission were similar between the groups. No difference existed between groups for length of hospital stay p = 0.793), and in the proportions remaining alive at 1 year (p = 0.416). When entered into a multivariate Cox regression analysis, the deprivation categories did not predict mortality. Age, sex, Philadelphia Geriatric Center Instrumental Activities of Daily Living (IADL) Scale Score, Orgogozo neurological score on admission, and ECG abnormalities were the significant predictors. Conclusions: Stroke patients living in more socially deprived areas had their strokes at an earlier age but were not at a greater risk of dying or longer hospital stay once they had been admitted to hospital. [ABSTRACT FROM AUTHOR]

Pathological conditions linked to imbalances in oxygen supply and demand (for example, ischaemia, hypoxia and heart failure) are associated with disruptions in intracellular sodium ([Na+]i) and calcium ([Ca2+]i) concentration homeostasis of myocardial cells. A decreased efflux or increased influx of sodium may cause cellular sodium overload. Sodium overload is followed by an increased influx of calcium through sodium–calcium exchange. Failure to maintain the homeostasis of [Na+)i and [Ca2+]i leads to electrical instability (arrhythmias), mechanical dysfunction (reduced contractility and increased diastolic tension) and mitochondrial dysfunction. These events increase ATP hydrolysis and decrease ATP formation and, if left uncorrected, they cause cell injury and death. The relative contributions of various pathways (sodium channels, exchangers and transporters) to the rise in [Na+]i remain a mailer of debate. Nevertheless, both the sodium-hydrogen exchanger and abnormal sodium channel conductance (that is, increased late sodium current (`INa)) are likely to contribute to the rise in [Na+]i. The focus of this review is on the role of the late (sustained/persistent) INa in the ionic disturbances associated with ischaemia/hypoxia and heart failure, the consequences of these ionic disturbances, and the cardioprotective effects of the antianginal and anti-ischaemic drug ranolazine. Ranolazine selectively inhibits late INa, reduces [Na+]i-dependent calcium overload and attenuates the abnormalities of ventricular repolarisation and contractility that are associated with ischaemia/ reperfusion and heart failure. Thus, inhibition of late INa can reduce [Na+]i-dependent calcium overload and its detrimental effects on myocardial function. [ABSTRACT FROM AUTHOR]

Structured protocols offer a transparent and systematic way to elicit and combine/aggregate, probabilistic predictions from multiple experts. These judgements can be aggregated behaviourally or mathematically to derive a final group prediction. Mathematical rules (e.g., weighted linear combinations of judgments) provide an objective approach to aggregation. The quality of this aggregation can be defined in terms of accuracy, calibration and informativeness. These measures can be used to compare different aggregation approaches and help decide on which aggregation produces the "best" final prediction. When experts' performance can be scored on similar questions ahead of time, these scores can be translated into performance-based weights, and a performance-based weighted aggregation can then be used. When this is not possible though, several other aggregation methods, informed by measurable proxies for good performance, can be formulated and compared. Here, we develop a suite of aggregation methods, informed by previous experience and the available literature. We differentially weight our experts' estimates by measures of reasoning, engagement, openness to changing their mind, informativeness, prior knowledge, and extremity, asymmetry or granularity of estimates. Next, we investigate the relative performance of these aggregation methods using three datasets. The main goal of this research is to explore how measures of knowledge and behaviour of individuals can be leveraged to produce a better performing combined group judgment. Although the accuracy, calibration, and informativeness of the majority of methods are very similar, a couple of the aggregation methods consistently distinguish themselves as among the best or worst. Moreover, the majority of methods outperform the usual benchmarks provided by the simple average or the median of estimates. [ABSTRACT FROM AUTHOR]

Sr2FeMoO6 (SFMO) films were grown on SrTiO3 (100)- and (111)-oriented substrates via pulsed laser deposition (PLD). In order to study the fundamental characteristics of deposition, films were grown in two different PLD chambers. In chamber I, the best films were grown with a relatively long substrate-to-target distance (89 mm), high substrate temperature (850 °C), and low pressure (50 mTorr) in a 95% Ar/5% H2 atmosphere. Although X-ray diffraction (XRD) measurements indicate these films are single phase, Rutherford Backscattering (RBS) measurements reveal considerable non-stoichiometry, corresponding to a Sr2+yFe1+xMo1-xO6 composition with x≅0.2-0.3. This level of non-stoichiometry results in inferior magnetic properties. In chamber II, the best films were grown with a much shorter substrate-to-target distance (38 mm), lower temperature (680 °C), and higher pressure (225 mTorr). XRD measurements show that the films are single phase, and RBS measurements indicate that they are nearly stoichiometric. The degree of ordering between Fe and Mo was dependent on both the temperature and pressure used during deposition, reaching a maximum order parameter of 85%. The saturation magnetization increases as the Fe/Mo ordering increases, reaching a maximum of 2.4 μB/f.u. Based on prior studies of bulk samples, one would expect a higher saturation magnetization for this degree of Fe/Mo order. The presence of extra strontium oxide layers in the form of Ruddlesden-Popper intergrowths appears to be responsible for the lower than expected saturation magnetization of these films. [ABSTRACT FROM AUTHOR]

Context. The interaction between dust, ice, and gas during the formation of stars produces complex organic molecules. While observations indicate that several species are formed on ice-covered dust grains and are released into the gas phase, the exact chemical interplay between solid and gas phases and their relative importance remain unclear. Aims. Our goal is to study the interplay between dust, ice, and gas in regions of low-mass star formation through ice- and gas-mapping and by directly measuring gas-to-ice ratios. This provides constraints on the routes that lead to the chemical complexity that is observed in solid and gas phases. Methods. We present observations of gas-phase methanol (CH3OH) and carbon monoxide (13CO and C18O) at 1.3 mm towards ten low-mass young protostars in the Serpens SVS 4 cluster from the SubMillimeter Array (SMA) and the Atacama Pathfinder EXperiment (APEX) telescope. We used archival data from the Very Large Telescope (VLT) to derive abundances of ice H2O, CO, and CH3OH towards the same region. Finally, we constructed gas-ice maps of SVS 4 and directly measured CO and CH3OH gas-to-ice ratios. Results. The SVS 4 cluster is characterised by a global temperature of 15 ± 5 K. At this temperature, the chemical behaviours of CH3OH and CO are anti-correlated: larger variations are observed for CH3OH gas than for CH3OH ice, whereas the opposite is seen for CO. The gas-to-ice ratios (Ngas/Nice) range from 1–6 for CO and 1.4 × 10−4–3.7 × 10−3 for CH3OH. The CO gas-maps trace an extended gaseous component that is not sensitive to the effect of freeze-out. Because of temperature variations and dust heating around 20 K, the frozen CO is efficiently desorbed. The CH3OH gas-maps, in contrast, probe regions where methanol is predominantly formed and present in ices and is released into the gas phase through non-thermal desorption mechanisms. Conclusions. Combining gas- and ice-mapping techniques, we measure gas-to-ice ratios of CO and CH3OH in the SVS 4 cluster. The CH3OH gas-to-ice ratio agrees with values that were previously reported for embedded Class 0/I low-mass protostars. We find that there is no straightforward correlation between CO and CH3OH gas with their ice counterparts in the cluster. This is likely related to the complex morphology of SVS 4: the Class 0 protostar SMM 4 and its envelope lie in the vicinity, and the outflow associated with SMM 4 intersects the cluster. This study serves as a pathfinder for future observations with ALMA and the James Webb Space Telescope (JWST) that will provide high-sensitivity gas-ice maps of molecules more complex than methanol. Such comparative maps will be essential to constrain the chemical routes that regulate the chemical complexity in star-forming regions. [ABSTRACT FROM AUTHOR]

The generation of cw Terahertz radiation from photomixing in low-temperature grown GaAs is limited by the thermal load for single emitters. We propose a new heat sinking scheme based on high thermal conductivity, transparent crystalline heat spreaders as diamond in direct contact with the active zone. A first working device based on recessed electrodes is demonstrated and has a significant power dissipation capability of more than 0.75 W (average). The electrical and terahertz characteristics are analyzed. [ABSTRACT FROM AUTHOR]

The effect of strains on the local crystallographic symmetry and structure of a Si/GexSi1-x model heterostructure grown on a (100) silicon substate was studied using convergent beam electron diffraction techniques and a cross-sectional specimen geometry. The alloy layers are seen to distort into relaxed tetragonal and monoclinic structures which are dependent on position and/or alloy composition. These observations can be explained in terms of strain relaxation in a thin-film specimen and deviations of the substrate from a perfect (100) orientation. The results have implications not only for the use of cross-sectioned specimens in the characterization of strained-layer heterostructures, but also for the band engineering of Si/GexSi1-x strained-layer superlattices and other materials which are grown on vicinal (100) and other low-symmetry substrate orientations. In particular relaxed tetragonal and monoclinic structures may be quite relevant to the emerging science of strain-induced lateral confinement of carriers in quantum well semiconductors. [ABSTRACT FROM AUTHOR]

Morphological and compositional evolution of omega (ω) precipitates in a model Titanium-20 wt%Vanadium (or 19 at.%V) alloy has been systematically investigated by coupling transmission electron microscopy and atom probe tomography with atomistic ab initio and continuum microelasticity computations. The initial water quenched microstructure comprised of a fine scale distribution of athermal ω precipitates, which form congruently from the β phase via a complete displacive collapse of {222} β planes, that has been rationalized based on DFT computations. Subsequent annealing at 300 °C, over progressively increasing time periods, resulted in isothermal evolution of the ω precipitates, whose morphology changes from ellipsoidal to cuboidal, accompanied with V rejection. The highly V-enriched β matrix consisted of short V V bond lengths, further distorting the bcc lattice, and increasing the β/ω misfit. This facilitates the change in the morphology of omega precipitates from ellipsoidal to cuboidal resulting in a {001} β habit plane for these precipitates. The coupled experimental and computational approach permits rationalizing the evolution of ω precipitate morphology and composition in such high β−ω misfit β-Ti alloys. [ABSTRACT FROM AUTHOR]

Plotkin et al. reply - The criticisms of our results by Hahn et al., Nielsen and Hubisz, and Chen, Emerson and Martin fall into three categories: the formal justification for our method, the potential for confounding factors, and the interpretation of our empirical results. [ABSTRACT FROM AUTHOR]

Themicrostructure of a high entropy alloy with composition ofMo0.5Al1Nb1Ta0.5Ti1Zr1 (the digits refer to molar volumes) has been characterised directly in three dimensions using TEM dark field (DF) imaging and by recording tilt pairmicrographs using STEMhigh angle annular DF (HAADF) imaging. The microstructure contains disordered bcc precipitates that appeared as orthogonal stacks of plate-like features. A tapered needle sample was prepared in a focused ion beam/SEM and was used to acquire a 180° tomographic dataset of STEM/HAADF images in 2° increments. The tilt series images were registered, and the algebraic reconstruction technique was used to reconstruct the three-dimensional microstructure. Thebccprecipitates were segmented using acombinative approach involving two threshold techniques. The precipitates were then visualised using commercial software, which revealed surprisingly the existence of both cuboidal and plate-like morphologies. Colouring each precipitate according to its morphology (determined using the omega-2 moment invariant) revealed a precipitate arrangement where plate-like features appeared parallel to each cuboid face. [ABSTRACT FROM AUTHOR]

The present paper describes the morphology, chemistry and crystallography of the phases observed in the silicide coatings produced by pack cementation technique on Nb based alloys. Cross-sectional microstructures examined by transmission electron microscopy and scanning electron microscopy techniques have shown that the coating has two silicide layers: NbSi 2 and Nb 5 Si 3 . NbSi 2 formed at the surface of the sample and Nb 5 Si 3 formed in between the substrate (Nb alloy) and NbSi 2 coating layer. Electron diffraction analyses revealed that NbSi 2 has hexagonal crystal structure with lattice parameters as a = 0.48 nm and c = 0.66 nm and Nb 5 Si 3 has tetragonal crystal structure with lattice parameters as a = 0.65 nm and c = 1.19 nm. Nb 5 Si 3 showed fine equiaxed grains, whereas, NbSi 2 exhibited duplex morphology having columnar grain morphology near to the Nb 5 Si 3 layer and large equiaxed grains at the surface of the coating sample. The presence of duplex morphology was explained by estimating diffusion of various species and it was shown that columnar morphology of grains could be attributed to outward diffusion of Nb and equiaxed grains to inward diffusion of Si. In the case of Nb 5 Si 3 , growth takes place due to single element Si diffusion, leading to development of single equiaxed grain morphology of the Nb 5 Si 3 phase. [ABSTRACT FROM AUTHOR]

Context. Understanding the collisional properties of ice is important for understanding both the early stages of planet formation and the evolution of planetary ring systems. Simple chemicals such as methanol and formic acid are known to be present in cold protostellar regions alongside the dominant water ice; they are also likely to be incorporated into planets which form in protoplanetary disks, and planetary ring systems. However, the effect of the chemical composition of the ice on its collisional properties has not yet been studied. Aims. Collisions of 1.5 cm ice spheres composed of pure crystalline water ice, water with 5% methanol, and water with 5% formic acid were investigated to determine the effect of the ice composition on the collisional outcomes. Methods. The collisions were conducted in a dedicated experimental instrument, operated under microgravity conditions, at relative particle impact velocities between 0.01 and 0.19 m s-1, temperatures between 131 and 160 K and a pressure of around 10-5 mbar. Results. A range of coefficients of restitution were found, with no correlation between this and the chemical composition, relative impact velocity, or temperature. Conclusions. We conclude that the chemical composition of the ice (at the level of 95% water ice and 5% methanol or formic acid) does not affect the collisional properties at these temperatures and pressures due to the inability of surface wetting to take place. At a level of 5% methanol or formic acid, the structure is likely to be dominated by crystalline water ice, leading to no change in collisional properties. The surface roughness of the particles is the dominant factor in explaining the range of coefficients of restitution. [ABSTRACT FROM AUTHOR]

Context. Planetisimals are thought to be formed from the solid material of a protoplanetary disk by a process of dust aggregation. It is not known how growth proceeds to kilometre sizes, but it has been proposed that water ice beyond the snowline might affect this process. Aims. To better understand collisional processes in protoplanetary disks leading to planet formation, the individual low velocity collisions of small ice particles were investigated. Methods. The particles were collided under microgravity conditions on a parabolic flight campaign using a purpose-built, cryogenically cooled experimental setup. The setup was capable of colliding pairs of small ice particles (between 4.7 and 10.8 mm in diameter) together at relative collision velocities of between 0.27 and 0.51 ms-1 at temperatures between 131 and 160 K. Two types of ice particle were used: ice spheres and irregularly shaped ice fragments. Results. Bouncing was observed in the majority of cases with a few cases of fragmentation. A full range of normalised impact parameters (b/R = 0.0-1.0) was realised with this apparatus. Coefficients of restitution were evenly spread between 0.08 and 0.65 with an average value of 0.36, leading to a minimum of 58% of translational energy being lost in the collision. The range of coefficients of restitution is attributed to the surface roughness of the particles used in the study. Analysis of particle rotation shows that up to 17% of the energy of the particles before the collision was converted into rotational energy. Temperature did not affect the coefficients of restitution over the range studied. [ABSTRACT FROM AUTHOR]

The formation of CO2 in quiescent molecular cores has long been of interest to astrochemists as CO2 is one of the most abundant solid phase molecules present in the interstellar medium. Previous studies have concentrated, for the most part, on formation mechanisms involving high energy particle or UV bombardment of ices, to mimic the influence of cosmic rays on solid phase species in the outer, lower density regions of molecular clouds. However, condensed phase CO2 is also observed in the inner, denser regions of clouds, where less UV radiation penetrates. To date, very few studies have been made of CO2 formation in the absence of energetic particles. Low-energy routes to the formation of CO2 are crucial to explain the high abundances of this molecule observed in quiescent regions. We discuss recent experimental results of a study of the low-energy reaction CO + OH. A simple model, developed to describe the kinetics of the system, suggests that the various reactions of the OH radical are key in characterising the production of CO2 and other species. Our results indicate that some CO2 forms concurrently with H2O in molecular clouds, in line with both previous observations and theory. The results of this research are published in Noble et al. (2011). [ABSTRACT FROM AUTHOR]

The development of a functional vascular tree within the primate ovary is critical for reproductive health. To determine the efficacy of contrast agents to image the microvascular environment within the primate ovary, contrast ultrasonography was performed in six reproductive-aged female common marmosets ( Callithrix jacchus) during the late luteal phase of the cycle, following injection of Sonovue™. Regions of interest ( ROIs), representing the corpus luteum ( CL) and noncorpus luteum ovarian tissue ( NCLOT), were selected during gray-scale B-mode ultrasound imaging. The magnitude of backscatter intensity of CL and NCLOT ROIs were calculated in Xn View, post hoc: subsequent gamma-variate modeling was implemented in Matlab to determine perfusion parameters. Histological analysis of these ovaries revealed a total of 11 CL, nine of which were identified during contrast ultrasonography. The median enhancement ratio was significantly increased in the CL (5.54 AU; 95% CI −2.21-68.71) compared to the NCLOT (2.82 AU; 95% CI 2.73-15.06; P < 0.05). There was no difference in time parameters between the CL and NCLOT. An additional avascular ROI was identified in the ovary of Animal 5, both histologically and by ultrasonography. This cystic ROI displayed a markedly lower enhancement ratio (0.79 AU) and higher time parameters than mean CL and NCLOT, including time to peak and time to wash out. These data demonstrate, for the first time, the ability of commercially available contrast agents, to differentiate structures within the nonhuman primate ovary. Contrast-enhanced ultrasonography has a promising future in reproductive medicine. Am. J. Primatol. 74:1088-1096, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Electron energy-loss spectroscopy (EELS) and energy dispersive x-ray (EDX) analysis in scanning transmission electron microscopy (STEM) have the ability to produce elemental maps of a specimen at atomic resolution. In this paper we present EELS and EDX maps for the oxygen K shell in (001) strontium titanate. The results initially seem to be anomalous since substantially more signal is obtained when the STEM probe is above the columns containing both titanium and oxygen than when it is above those containing only oxygen. This is at variance with the stoichiometry: the density of oxygen in both types of columns is the same. Using theory, we show that an understanding of the direct contribution to the recorded signal from electrons which have been thermally scattered is the key to understanding these results. We contrast these results with elemental maps of (110) strontium titanate. While the experimental results are not directly interpretable, they are in concert with simulations from first principles such as those presented in this paper. [ABSTRACT FROM AUTHOR]

Stroke is the most common cause of complex disability in the community. Physical fitness is often reduced after stroke, but training can improve fitness and function. UK and international stroke clinical guidelines recommend long-term exercise participation for stroke survivors. However, there has been no previous research into what services are available to support this. In 2009, we conducted the first European survey of community Exercise after Stroke services. A link to our web-based survey was emailed to health, leisure service and stroke charity contacts in Scotland with email and telephone follow-up to non-respondents. The overall response rate was 64% (230/361). A total of 14 Exercise after Stroke services were identified, the majority of which were run by charity collaborations (7/14), followed by leisure centre services (4/14) and health services (3/14). We sought information on session content, referral and assessment processes, and the qualifications of exercise instructors. This information was cross-referenced with current clinical and exercise guidelines to determine whether existing resources were sufficient to meet stroke survivors' needs for safe, effective and sustainable access to exercise. The results indicated a shortage of stroke-specific community exercise programmes. Further service development is required to ensure appropriate instructor training and referral pathways are in place to enable stroke survivors to access exercise services in accordance with current guidelines. [ABSTRACT FROM AUTHOR]

We report growth of Sr2CrRe06 epitaxial films with 99% Cr/Re ordering and crystalline perfection comparable to those of high-quality semiconductor films. The Sr2CrReO6 films show a Curie temperature of 508 Κ and a saturation magnetization of 1.29 µΒ per formula unit, which confirms the presence of strong spin-orbit coupling. Unexpectedly, electrical transport and optical absorption measurements indicate that Sr2CrRe06 is a semiconductor with a band gap of 0.21 eV. The unique combination of high temperature ferrimagnetism and semiconductivity is both scientifically interesting and highly attractive for applications. [ABSTRACT FROM AUTHOR]

ABSTRACT The desorption characteristics of molecules on interstellar dust grains are important for modelling the behaviour of molecules in icy mantles and, critically, in describing the solid-gas interface. In this study, a series of laboratory experiments exploring the desorption of three small molecules from three astrophysically relevant surfaces is presented. The desorption of CO, O2 and CO2 at both submonolayer and multilayer coverages was investigated from non-porous water, crystalline water and silicate surfaces. Experimental data were modelled using the Polanyi-Wigner equation to produce a mathematical description of the desorption of each molecular species from each type of surface, uniquely describing both the monolayer and multilayer desorption in a single combined model. The implications of desorption behaviour over astrophysically relevant time-scales are discussed. [ABSTRACT FROM AUTHOR]

Context. Circumstellar disks and envelopes of low-mass young stellar objects (YSOs) contain significant amounts of ice. Such icy material will evolve to become volatile components of planetary systems, such as comets in our solar system. Aims. To investigate the composition and evolution of circumstellar ice around low-mass young stellar objects (YSOs), we observed ice absorption bands in the near infrared (NIR) towards eight YSOs ranging from class 0 to class II, among which seven are associated with edge-on disks. Methods. We performed slit-less spectroscopic observations using the grism mode of the InfraRed Camera (IRC) on board AKARI, which enables us to obtain full NIR spectra from 2.5 μm to 5 μm, including the CO2 band and the blue wing of the H2O band, which are inaccessible from the ground. We developed procedures to carefully process the spectra of targets with nebulosity. The spectra were fitted with polynomial baselines to derive the absorption spectra. The molecular absorption bands were then fitted with the laboratory database of ice absorption bands, considering the instrumental line profile and the spectral resolution of the grism dispersion element. Results. Towards the class 0-I sources (L1527, IRC-L1041-2, and IRAS 04302), absorption bands of H2O, CO2, CO, and XCN are clearly detected. Column density ratios of CO2 ice and CO ice relative to H2O ice are 21-28% and 1346%, respectively. If XCN is OCN, its column density is as high as 2-6% relative to H2O ice. The HDO ice feature at 4.1 μm is tentatively detected towards the class 0-I sources and HV Tau. Non-detections of the CH-stretching mode features around 3.5 μm provide upper limits to the CH3OH abundance of 26% (L1527) and 42% (IRAS 04302) relative to H2O. We tentatively detect OCS ice absorption towards IRC-L1041-2. Towards class 0-I sources, the detected features should mostly originate in the cold envelope, while CO gas and OCN- could originate in the region close to the protostar, where there are warm temperatures and UV radiation. We detect H2O ice band towards ASR41 and 2MASSJ 1628137-243139, which are edge-on class II disks. We also detect H2O ice and CO2 ice towards HV Tau, HK Tau, and UY Aur, and tentatively detect CO gas features towards HK Tau and UY Aur [ABSTRACT FROM AUTHOR]

The formation of CO2 in quiescent regions of molecular clouds is not yet fully understood, despite CO2 having an abundance of around 10%-34% H2O. We present a study of the formation of CO2 via the nonenergetic route CO + OH on nonporous H2O and amorphous silicate surfaces. Our results are in the form of temperature-programmed desorption spectra of CO2 produced via two experimental routes: O2 + CO + H and O3 + CO + H. The maximum yield of CO2 is around 8% with respect to the starting quantity of CO, suggesting a barrier to CO + OH. The rate of reaction, based on modeling results, is 24 times slower than O2 + H. Our model suggests that competition between CO2 formation via CO + OH and other surface reactions of OH is a key factor in the low yields of CO2 obtained experimentally, with relative reaction rates of kCO+H ⪡ kCO+OH < kH2O2+H < kOH+H, kO2+H. Astrophysically, the presence of CO2 in low AV regions of molecular clouds could be explained by the reaction CO + OH occurring concurrently with the formation of H2O via the route OH + H. [ABSTRACT FROM AUTHOR]

Background: WEQAS, one of the largest EQA (External Quality Assessment) providers in the UK, offers a bile acid EQA scheme, with linear serum pools containing cholic acid, deoxycholic acid and chenodeoxycholic acid, reflecting levels observed in obstructive cholestasis. Total bile acids are currently measured routinely by non-specific enzymatic methods. Traceability of results to the SI unit utilizing reference target values is the preferred method of comparison of returned results where available, ensuring the transfer of accuracy from definitive methods to routine methods. Methods: Target values have been assigned to EQA material utilizing isotope dilution gas chromatography mass spectrometry (ID-GCMS). The methodology was based on published routine methods and adapted for use as a ID-GCMS target method. The total bile acid target value was reported as the sum of the three major bile acids measured: cholic acid, deoxycholic acid and chenodeoxycholic acid. Results: The produced target values have been used to assess the performance of total bile acid methods. A degree of variability was observed between the third-generation enzyme-formazan methods and the fifth-generation thio-NADH methods. Additionally, the Sentinel results showed a positive bias in comparison to their peer formazan method group. Conclusion: The use of ID-GCMS target results provides a common comparison for resumed results in EQA schemes, highlighting any method differences. Thus can then aid in the harmonisation of results observed for each of the different methods. [ABSTRACT FROM AUTHOR]