A study into the effect of cleat demineralisation by hydrochloric acid on the permeability of coal

Mineral occlusions in cleats are known to considerably reduce coal permeability. Sequential steady state core flooding experiments with aqueous hydrochloric acid (HCl) solutions were conducted on whole core samples from the Bowen Basin, Australia, to assess the effect of mineral dissolution on core permeability. Cleat minerals were characterised by scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM-EDS). Generally, the cleats contained kaolinite and carbonates which were present in various proportions as either single phases or mixed. An immediate increase in permeability was obtained after HCl was flooded through for the majority of tests. This increase coincided with heightened concentrations of Ca and Fe in the effluent and is attributed to the dissolution of acid soluble minerals, mainly calcite and siderite. In some cases the increase in permeability was very high (200 times increase) and sustained whilst in other cases there was a gradual decrease after the initial increase, resulting in either a small overall increase in permeability of about 20–30% or a decline in permeability relative to the original level of about 20–30%. A possible reason for permeability decline is that although dissolution of minerals allows more liquid into the core, it is not enhancing flow paths, i.e. restrictions to flow in the cleats still exist. Another reason could be destabilisation of insoluble minerals, causing them to become mobile fines in the liquid which migrate toward restrictions in the flow and then jam. High and sustained permeability increases are attributed to cleats containing solely calcite in addition to having high connectivity. This investigation has shown that cleat demineralisation using HCl can be an effective means to overcome low permeability provided cleat connectivity and mineralogy are characterised

Time, spatial, and spectral resolution of the Halpha line-formation region of Deneb and Rigel with the VEGA/CHARA interferometer

BA-type supergiants are amongst the most optically-bright stars. They are observable in extragalactic environments, hence potential accurate distance indicators. Emission activity in the Halpha line of the BA supergiants Rigel (B8Ia) and Deneb (A2Ia) is indicative of presence of localized time-dependent mass ejections. Here, we employ optical interferometry to study the Halpha line-formation region in these stellar environments. High spatial- (0.001 arcsec) and spectral- (R=30 000) resolution observations of Halpha were obtained with the visible recombiner VEGA installed on the CHARA interferometer, using the S1S2 array-baseline (34m). Six independent observations were done on Deneb over the years 2008 and 2009, and two on Rigel in 2009. We analyze this dataset with the 1D non-LTE radiative-transfer code CMFGEN, and assess the impact of the wind on the visible and near-IR interferometric signatures, using both Balmer-line and continuum photons. We observe a visibility decrease in Halpha for both Rigel and Deneb, suggesting that the line-formation region is extended (1.5-1.75 R*). We observe a significant visibility decrease for Deneb in the SiII6371 line. We witness time variations in the differential phase for Deneb, implying an inhomogeneous and unsteady circumstellar environment, while no such variability is seen in differential visibilities. Radiative-transfer modeling of Deneb, with allowance for stellar-wind mass loss, accounts fairly well for the observed decrease in the Halpha visibility. Based on the observed differential visibilities, we estimate that the mass-loss rate of Deneb has changed by less than 5%

The Two-Phase, Two-Velocity Ionized Absorber in the Seyfert 1 Galaxy NGC 5548

We present an analysis of X-ray high quality grating spectra of the Seyfert 1 galaxy NGC 5548 using archival Chandra HETGS and LETGS observations for a total exposure time of 800ks. The continuum emission is well represented by a powerlaw plus a black-body component. We find that the well known X-ray warm absorber in this source consists of two different outflow velocity systems. Recognizing the presence of these kinematically distinct components allows each system to be fitted independently, each with two absorption components with different ionization levels. The high velocity system consists of a component with temperature of 2.7X10^6K and another component with temperature of 5.8X10^5K. The low-velocity system required also two absorbing components, one with temperature of 5.8X10^5K; the other with lower temperature (3.5X10^4K). Once these components are considered, the data do not require any further absorbers. In particular, a model consisting of a continuous radial range of ionization structures is not required. The two absorbing components in each velocity system are in pressure equilibrium with each other. This suggests that each velocity system consists of a multi-phase medium. This is the first time that different outflow velocity systems have been modelled independently in the X-ray band for this source. The kinematic components and column densities found from the X-rays are in agreement with the main kinematic components found in the UV absorber. This supports the idea that the UV and X-ray absorbing gas is part of the same phenomenon. NGC 5548 can now be seen to fit in a pattern established for other warm absorbers: 2 or 3 discrete phases in pressure equilibrium. There are no remaining cases of a well studied warm absorber in which a model consisting of a multi-phase medium is not viable.Comment: To appear on The Astrophysical Journal March 1, 201

Effect of Parent Training on Adaptive Behavior in Children With Autism Spectrum Disorder and Disruptive Behavior: Results of a Randomized Trial

Objective This study examined the impact of parent training on adaptive behavior in children with autism spectrum disorder (ASD) and disruptive behavior. Methods This was a 24-week, 6-site, randomized trial of parent training versus parent education in 180 children with ASD (aged 3−7 years; 158 boys and 22 girls) and moderate or greater behavioral problems. Parent training included specific strategies to manage disruptive behavior over 11 to 13 sessions, 2 telephone boosters, and 2 home visits. Parent education provided useful information about autism but no behavior management strategies over 12 core sessions and 1 home visit. In a previous report, we showed that parent training was superior to parent education in reducing disruptive behavior in young children with ASD. Here, we test whether parent training is superior to parent education in improving daily living skills as measured by the parent-rated Vineland Adaptive Behavior Scales II. The long-term impact of parent training on adaptive functioning is also presented. Results At week 24, the parent training group showed a 5.7-point improvement from baseline on the Daily Living domain compared to no change in parent education (p = .004; effect size = 0.36). On the Socialization domain, there was a 5.9-point improvement in parent training versus a 3.1-point improvement in parent education (p = .11; effect size = 0.29). Gains in the Communication domain were similar across treatment groups. The gain in Daily Living was greater in children with IQ of >70. However, the interaction of treatment-by-IQ was not significant. Gains in Daily Living at week 24 were maintained upon re-evaluation at 24 weeks posttreatment. Conclusion These results support the model that reduction in disruptive behavior can lead to improvement in activities of daily living. By contrast, the expected trajectory for adaptive behavior in children with ASD is often flat and predictably declines in children with intellectual disability. In the parent training group, higher-functioning children achieved significant gains in daily living skills. Children with intellectual disability kept pace with time

Mechanisms Models and Biomarkers in Amyotrophic Lateral Sclerosis

The last 30 years have seen a major advance in the understanding of the clinical and pathological heterogeneity of amyotrophic lateral sclerosis (ALS), and its overlap with frontotemporal dementia. Multiple, seemingly disparate biochemical pathways converge on a common clinical syndrome characterized by progressive loss of upper and lower motor neurons. Pathogenic themes in ALS include excitotoxicity, oxidative stress, mitochondrial dysfunction, neuroinflammation, altered energy metabolism, and most recently RNA mis-processing. The transgenic rodent, overexpressing mutant superoxide dismutase-1, is now only one of several models of ALS pathogenesis. The nematode, fruit fly and zebrafish all offer fresh insight, and the development of induced pluripotent stem cell-derived motor neurons holds promise for the screening of candidate therapeutics. The lack of useful biomarkers in ALS contributes to diagnostic delay, and the inability to stratify patients by prognosis may be an important factor in the failure of therapeutic trials. Biomarkers sensitive to disease activity might lessen reliance on clinical measures and survival as trial endpoints and reduce study length. Emerging proteomic markers of neuronal loss and glial activity in cerebrospinal fluid, a cortical signature derived from advanced structural and functional MRI, and the development of more sensitive measurements of lower motor neuron physiology are leading a new phase of biomarker-driven therapeutic discovery

Midgut microbiota of the malaria mosquito vector Anopheles gambiae and Interactions with plasmodium falciparum Infection

The susceptibility of Anopheles mosquitoes to Plasmodium infections relies on complex interactions between the insect vector and the malaria parasite. A number of studies have shown that the mosquito innate immune responses play an important role in controlling the malaria infection and that the strength of parasite clearance is under genetic control, but little is known about the influence of environmental factors on the transmission success. We present here evidence that the composition of the vector gut microbiota is one of the major components that determine the outcome of mosquito infections. A. gambiae mosquitoes collected in natural breeding sites from Cameroon were experimentally challenged with a wild P. falciparum isolate, and their gut bacterial content was submitted for pyrosequencing analysis. The meta-taxogenomic approach revealed a broader richness of the midgut bacterial flora than previously described. Unexpectedly, the majority of bacterial species were found in only a small proportion of mosquitoes, and only 20 genera were shared by 80% of individuals. We show that observed differences in gut bacterial flora of adult mosquitoes is a result of breeding in distinct sites, suggesting that the native aquatic source where larvae were grown determines the composition of the midgut microbiota. Importantly, the abundance of Enterobacteriaceae in the mosquito midgut correlates significantly with the Plasmodium infection status. This striking relationship highlights the role of natural gut environment in parasite transmission. Deciphering microbe-pathogen interactions offers new perspectives to control disease transmission.Institut de Recherche pour le Developpement (IRD); French Agence Nationale pour la Recherche [ANR-11-BSV7-009-01]; European Community [242095, 223601]info:eu-repo/semantics/publishedVersio

Comparative in vitro activity of Meropenem, Imipenem and Piperacillin/tazobactam against 1071 clinical isolates using 2 different methods: a French multicentre study

<p>Abstract</p> <p>Background</p> <p>Meropenem is a carbapenem that has an excellent activity against many gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria. The major objective of the present study was to assess the <it>in vitro </it>activity of meropenem compared to imipenem and piperacillin/tazobactam, against 1071 non-repetitive isolates collected from patients with bacteremia (55%), pneumonia (29%), peritonitis (12%) and wound infections (3%), in 15 French hospitals in 2006. The secondary aim of the study was to compare the results of routinely testings and those obtained by a referent laboratory.</p> <p>Method</p> <p>Susceptibility testing and Minimum Inhibitory Concentrations (MICs) of meropenem, imipenem and piperacillin/tazobactam were determined locally by Etest method. Susceptibility to meropenem was confirmed at a central laboratory by disc diffusion method and MICs determined by agar dilution method for meropenem, imipenem and piperacillin/tazobactam.</p> <p>Results</p> <p>Cumulative susceptibility rates against <it>Escherichia coli </it>were, meropenem and imipenem: 100% and piperacillin/tazobactam: 90%. Against other <it>Enterobacteriaceae</it>, the rates were meropenem: 99%, imipenem: 98% and piperacillin/tazobactam: 90%. All <it>Staphylococci</it>, <it>Streptococci </it>and anaerobes were susceptible to the three antibiotics. Against non fermeters, meropenem was active on 84-94% of the strains, imipenem on 84-98% of the strains and piperacillin/tazobactam on 90-100% of the strains.</p> <p>Conclusions</p> <p>Compared to imipenem, meropenem displays lower MICs against <it>Enterobacteriaceae</it>, <it>Escherichia coli </it>and <it>Pseudomonas aeruginosa</it>. Except for non fermenters, MICs90 of carbapenems were <4 mg/L. Piperacillin/tazobactam was less active against <it>Enterobacteriaceae </it>and <it>Acinetobacter </it>but not <it>P. aeruginosa</it>. Some discrepancies were noted between MICs determined by Etest accross centres and MICs determined by agar dilution method at the central laboratory. Discrepancies were more common for imipenem testing and more frequently related to a few centres. Overall MICs determined by Etest were in general higher (0.5 log to 1 log fold) than MICs by agar dilution.</p

Investigation of the international comparability of population-based routine hospital data set derived comorbidity scores for patients with lung cancer

Introduction: The International Cancer Benchmarking Partnership (ICBP) identified significant international differences in lung cancer survival. Differing levels of comorbid disease across ICBP countries has been suggested as a potential explanation of this variation but, to date, no studies have quantified its impact. This study investigated whether comparable, robust comorbidity scores can be derived from the different routine population-based cancer data sets available in the ICBP jurisdictions and, if so, use them to quantify international variation in comorbidity and determine its influence on outcome. Methods: Linked population-based lung cancer registry and hospital discharge data sets were acquired from nine ICBP jurisdictions in Australia, Canada, Norway and the UK providing a study population of 233 981 individuals. For each person in this cohort Charlson, Elixhauser and inpatient bed day Comorbidity Scores were derived relating to the 4–36 months prior to their lung cancer diagnosis. The scores were then compared to assess their validity and feasibility of use in international survival comparisons. Results: It was feasible to generate the three comorbidity scores for each jurisdiction, which were found to have good content, face and concurrent validity. Predictive validity was limited and there was evidence that the reliability was questionable. Conclusion: The results presented here indicate that interjurisdictional comparability of recorded comorbidity was limited due to probable differences in coding and hospital admission practices in each area. Before the contribution of comorbidity on international differences in cancer survival can be investigated an internationally harmonised comorbidity index is required

(En)gendering the political: Citizenship from marginal spaces

This introduction sets out the central concerns of this special issue, the relationship between marginality and the political. In doing so it makes the argument that the process of marginalisation, the sites and experiences of ‘marginality’ provide a different lens through which to understand citizenship. Viewing the political as the struggle over belonging it considers how recent studies of citizenship have understood political agency. It argues that marginality can help us understand multiple scales, struggles and solidarities both within and beyond citizenship. Whilst there is a radical potential in much of the existing literature in citizenship studies it is also important to consider political subjectivities and acts which are not subsumed by right claims. Exploring marginality in this way means understanding how subjects are disenfranchised by regimes of citizenship and at the same how time this also (en)genders new political possibilities which are not always orientated towards 'inclusion'. The introduction then sets out how each article contributes to this project