337 research outputs found

    Low Temperature Synthesis, Chemical and Electrochemical Characterization of LiNi(x)Co(1-x)O2 (0 less than x less than 1)

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    A new method of synthesis for the solid solution cathode materials LiNi(x)Co(1-x)O2 (0 less than x less than 1) involving enhanced reactions at temperatures less than or equal to 700 deg. C, between metal oxy-hydroxide precursors MOOH (M = Ni, Co) and Li-salts (Li2CO3, LiOH, and LiNO3) has been investigated. The effects of synthesis conditions and sources of Li, on phase purity, microstructure, and theoretical electrochemical capacity (total M(3+) content) are characterized by powder X-ray diffraction analysis, scanning electron microscopy, chemical analysis and room temperature magnetic susceptibility. An attempt has been made to correlate the electrochemical properties with the synthesis conditions and microstructure

    Party control, party competition and public service performance

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    publication-status: Acceptedtypes: ArticleThis article assesses party effects on the performance of public services. A policy-seeking model, hypothesizing that left and right party control affects performance, and an instrumental model, where all parties strive to raise performance, are presented. The framework also suggests a mixed model in which party effects are contingent on party competition, with parties raising performance as increasing party competition places their control of government at increasing risk. These models are tested against panel data on English local governments’ party control and public service performance. The results question the traditional account of left and right parties, showing a positive relationship between rightwing party control and performance that is contingent on a sufficiently high level of party competition. The findings suggest left–right models should be reframed for the contemporary context

    Mesophilic mineral-weathering bacteria inhabit the critical-zone of a perennially cold basaltic environment

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    The weathering of silicate in the world’s critical-zone (rock-soil interface) is a natural mechanism providing a feedback on atmospheric CO2 concentrations through the carbonate-silicate cycle. We examined culturable bacterial communities from a critical-zone in western Iceland to determine the optimum growth temperature, ability to solubilise phosphate-containing minerals, which are abundant within the critical-zone area examined here. The majority of isolated bacteria were able to solubilize mineral-state phosphate. Almost all bacterial isolates were mesophilic (growth optima of 20-45°C), despite critical-zone temperatures that were continuously below 15°C, although all isolates could grow at temperatures associated with the critical-zone (-2.8 – 13.1°C). Only three isolates were shown to have thermal optima for growth that were within temperatures experienced at the critical-zone. These findings show that the bacteria that inhabit the western Icelandic critical-zone have temperature growth optima suboptimally adapted to their environment, implying that other adaptations may be more important for their long-term persistence in this environment. Moreover, our study showed that the cold basaltic critical-zone is a region of active phosphate mineral-weathering

    Additive-Free, Low-Temperature Crystallization of Stable α-FAPbI3 Perovskite

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    Formamidinium lead triiodide (FAPbI3) is attractive for photovoltaic devices due to its optimal bandgap at around 1.45 eV and improved thermal stability compared with methylammonium‐based perovskites. Crystallization of phase‐pure α‐FAPbI3 conventionally requires high‐temperature thermal annealing at 150 °C whilst the obtained α‐FAPbI3 is metastable at room temperature. Here, aerosol‐assisted crystallization (AAC) is reported, which converts yellow δ‐FAPbI3 into black α‐FAPbI3 at only 100 °C using precursor solutions containing only lead iodide and formamidinium iodide with no chemical additives. The obtained α‐FAPbI3 exhibits remarkably enhanced stability compared to the 150 °C annealed counterparts, in combination with improvements in film crystallinity and photoluminescence yield. Using X‐ray diffraction, X‐ray scattering, and density functional theory simulation, it is identified that relaxation of residual tensile strains, achieved through the lower annealing temperature and post‐crystallization crystal growth during AAC, is the key factor that facilitates the formation of phase‐stable α‐FAPbI3. This overcomes the strain‐induced lattice expansion that is known to cause the metastability of α‐FAPbI3. Accordingly, pure FAPbI3 p–i–n solar cells are reported, facilitated by the low‐temperature (≤100 °C) AAC processing, which demonstrates increases of both power conversion efficiency and operational stability compared to devices fabricated using 150 °C annealed films

    Expression quantitative trait loci are highly sensitive to cellular differentiation state

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    Blood cell development from multipotent hematopoietic stem cells to specialized blood cells is accompanied by drastic changes in gene expression for which the triggers remain mostly unknown. Genetical genomics is an approach linking natural genetic variation to gene expression variation, thereby allowing the identification of genomic loci containing gene expression modulators (eQTLs). In this paper, we used a genetical genomics approach to analyze gene expression across four developmentally close blood cell types collected from a large number of genetically different but related mouse strains. We found that, while a significant number of eQTLs (365) had a consistent “static” regulatory effect on gene expression, an even larger number were found to be very sensitive to cell stage. As many as 1,283 eQTLs exhibited a “dynamic” behavior across cell types. By looking more closely at these dynamic eQTLs, we show that the sensitivity of eQTLs to cell stage is largely associated with gene expression changes in target genes. These results stress the importance of studying gene expression variation in well-defined cell populations. Only such studies will be able to reveal the important differences in gene regulation between different ce

    Understanding and Challenging Populist Negativity towards Politics: The Perspectives of British Citizens

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    This article adapts and develops the idea of a cynical or ‘stealth’ understanding of politics to explore how citizens’ estrangement from formal politics is processed cognitively through a populist lens. Earlier work has shown the widespread presence of stealth attitudes in the United States and Finland. We show that stealth attitudes are also well established in Britain, demonstrate their populist character and reveal that age, newspaper readership and concerns about governing practices help predict their adoption by individuals. Yet our survey findings also reveal a larger body of positive attitudes towards the practice of democracy suggesting that there is scope for challenging populist cynicism. We explore these so-called ‘sunshine’ attitudes and connect them to the reform options favoured by British citizens. If we are to challenge populist negativity towards politics, we conclude that improving the operation of representative politics is more important than offering citizens new forms of more deliberative participation

    Personalised asthma action plans for adults with asthma

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    BACKGROUND: A key aim of asthma care is to empower each person to take control of his or her own condition. A personalised asthma action plan (PAAP), also known as a written action plan, an individualised action plan, or a self-management action plan, contributes to this endeavour. A PAAP includes individualised self-management instructions devised collaboratively with the patient to help maintain asthma control and regain control in the event of an exacerbation. A PAAP includes baseline characteristics (such as lung function), maintenance medication and instructions on how to respond to increasing symptoms and when to seek medical help. OBJECTIVES: To evaluate the effectiveness of PAAPs used alone or in combination with education, for patient-reported outcomes, resource use and safety among adults with asthma. SEARCH METHODS: We searched the Cochrane Airways Group Specialised Register of trials, clinical trial registers, reference lists of included studies and review articles, and relevant manufacturers' websites up to 14 September 2016. SELECTION CRITERIA: We included parallel randomised controlled trials (RCTs), both blinded and unblinded, that evaluated written PAAPs in adults with asthma. Included studies compared PAAP alone versus no PAAP, and/or PAAP plus education versus education alone. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted study characteristics and outcome data and assessed risk of bias for each included study. Primary outcomes were number of participants reporting at least one exacerbation requiring an emergency department (ED) visit or hospitalisation, asthma symptom scores on a validated scale and adverse events (all causes). Secondary outcomes were quality of life measured on a validated scale, number of participants reporting at least one exacerbation requiring systemic corticosteroids, respiratory function and days lost from work or study. We used a random-effects model for all analyses and standard Cochrane methods throughout. MAIN RESULTS: We identified 15 studies described in 27 articles that met our inclusion criteria. These 15 included studies randomised a total of 3062 participants (PAAP vs no PAAP: 2602 participants; PAAP plus education vs education alone: 460 participants). Ten studies (eight PAAP vs no PAAP; two PAAP plus education vs education alone) provided outcome data that contributed to quantitative analyses. The overall quality of evidence was rated as low or very low.Fourteen studies lasted six months or longer, and the remaining study lasted for 14 weeks. When reported, mean age ranged from 22 to 49 years and asthma severity ranged from mild to severe/high risk. PAAP alone compared with no PAAPResults showed no clear benefit or harm associated with PAAPs in terms of the number of participants requiring an ED visit or hospitalisation for an exacerbation (odds ratio (OR) 0.75, 95% confidence interval (CI) 0.45 to 1.24; 1385 participants; five studies; low-quality evidence), change from baseline in asthma symptoms (mean difference (MD) -0.16, 95% CI -0.25 to - 0.07; 141 participants; one study; low-quality evidence) or the number of serious adverse events, including death (OR 3.26, 95% CI 0.33 to 32.21; 125 participants; one study; very low-quality evidence). Data revealed a statistically significant improvement in quality of life scores for those receiving PAAP compared with no PAAP (MD 0.18, 95% CI 0.05 to 0.30; 441 participants; three studies; low-quality evidence), but this was below the threshold for a minimum clinically important difference (MCID). Results also showed no clear benefit or harm associated with PAAPs on the number of participants reporting at least one exacerbation requiring oral corticosteroids (OR 1.45, 95% CI 0.84 to 2.48; 1136 participants; three studies; very low-quality evidence) nor on respiratory function (change from baseline forced expiratory volume in one second (FEV1): MD -0.04 L, 95% CI -0.25L to 0.17 L; 392 participants; three studies; low-quality evidence). In one study, PAAPs were associated with significantly fewer days lost from work or study (MD -6.20, 95% CI -7.32 to - 5.08; 74 participants; low-quality evidence). PAAP plus education compared with education aloneResults showed no clear benefit or harm associated with adding a PAAP to education in terms of the number of participants requiring an ED visit or hospitalisation for an exacerbation (OR 1.08, 95% CI 0.27 to 4.32; 70 participants; one study; very low-quality evidence), change from baseline in asthma symptoms (MD -0.10, 95% CI -0.54 to 0.34; 70 participants; one study; low-quality evidence), change in quality of life scores from baseline (MD 0.13, 95% CI -0.13 to 0.39; 174 participants; one study; low-quality evidence) and number of participants requiring oral corticosteroids for an exacerbation (OR 0.28, 95% CI 0.07 to 1.12; 70 participants; one study; very low-quality evidence). No studies reported serious adverse events, respiratory function or days lost from work or study. AUTHORS' CONCLUSIONS: Analysis of available studies was limited by variable reporting of primary and secondary outcomes; therefore, it is difficult to draw firm conclusions related to the effectiveness of PAAPs in the management of adult asthma. We found no evidence from randomised controlled trials of additional benefit or harm associated with use of PAAP versus no PAAP, or PAAP plus education versus education alone, but we considered the quality of the evidence to be low or very low, meaning that we cannot be confident in the magnitude or direction of reported treatment effects. In the context of this caveat, we found no observable effect on the primary outcomes of hospital attendance with an asthma exacerbation, asthma symptom scores or adverse events. We recommend further research with a particular focus on key patient-relevant outcomes, including exacerbation frequency and quality of life, in a broad spectrum of adults, including those over 60 years of age

    Some Like It Fat: Comparative Ultrastructure of the Embryo in Two Demosponges of the Genus Mycale (Order Poecilosclerida) from Antarctica and the Caribbean

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    0000-0002-7993-1523© 2015 Riesgo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License [4.0], which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

    Molecular Adaptations for Sensing and Securing Prey and Insight into Amniote Genome Diversity from the Garter Snake Genome

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    Colubridae represents the most phenotypically diverse and speciose family of snakes, yet no well-assembled and annotated genome exists for this lineage. Here, we report and analyze the genome of the garter snake, Thamnophis sirtalis, a colubrid snake that is an important model species for research in evolutionary biology, physiology, genomics, behavior, and the evolution of toxin resistance. Using the garter snake genome, we show how snakes have evolved numerous adaptations for sensing and securing prey, and identify features of snake genome structure that provide insight into the evolution of amniote genomes. Analyses of the garter snake and other squamate reptile genomes highlight shifts in repeat element abundance and expansion within snakes, uncover evidence of genes under positive selection, and provide revised neutral substitution rate estimates for squamates. Our identification of Z and W sex chromosome-specific scaffolds provides evidence for multiple origins of sex chromosome systems in snakes and demonstrates the value of this genome for studying sex chromosome evolution. Analysis of gene duplication and loss in visual and olfactory gene families supports a dim-light ancestral condition in snakes and indicates that olfactory receptor repertoires underwent an expansion early in snake evolution. Additionally, we provide some of the first links between secreted venom proteins, the genes that encode them, and their evolutionary origins in a rear-fanged colubrid snake, together with new genomic insight into the coevolutionary arms race between garter snakes and highly toxic newt prey that led to toxin resistance in garter snakes

    Transmural Ultrasound-based Visualization of Patterns of Action Potential Wave Propagation in Cardiac Tissue

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    The pattern of action potential propagation during various tachyarrhythmias is strongly suspected to be composed of multiple re-entrant waves, but has never been imaged in detail deep within myocardial tissue. An understanding of the nature and dynamics of these waves is important in the development of appropriate electrical or pharmacological treatments for these pathological conditions. We propose a new imaging modality that uses ultrasound to visualize the patterns of propagation of these waves through the mechanical deformations they induce. The new method would have the distinct advantage of being able to visualize these waves deep within cardiac tissue. In this article, we describe one step that would be necessary in this imaging process—the conversion of these deformations into the action potential induced active stresses that produced them. We demonstrate that, because the active stress induced by an action potential is, to a good approximation, only nonzero along the local fiber direction, the problem in our case is actually overdetermined, allowing us to obtain a complete solution. Use of two- rather than three-dimensional displacement data, noise in these displacements, and/or errors in the measurements of the fiber orientations all produce substantial but acceptable errors in the solution. We conclude that the reconstruction of action potential-induced active stress from the deformation it causes appears possible, and that, therefore, the path is open to the development of the new imaging modality
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