Strategies of actin reorganisation in plant cells

Spatial-temporal flexibility of the actin filament network (F-actin) is essential for all basic cellular functions and is governed by a stochastic dynamic model. In this model, actin filaments that randomly polymerise from a pool of free actin are bundled with other filaments and severed by ADF/cofilin. The fate of the severed fragments is not known. It has been proposed that the fragments are disassembled and the monomeric actin recycled for the polymerisation of new filaments. Here, we have generated tobacco cell lines and Arabidopsis plants expressing the actin marker Lifeact to address the mechanisms of F-actin reorganisation in vivo. We found that F-actin is more dynamic in isotropically expanding cells and that the density of the network changes with a periodicity of 70 seconds. The depolymerisation rate, but not the polymerisation rate, of F-actin increases when microtubules are destabilised. New filaments can be assembled from shorter free cytoplasmic fragments, from the products of F-actin severing and by polymerisation from the ends of extant filaments. Thus, remodelling of F-actin might not require bulk depolymerisation of the entire network, but could occur via severing and end-joining of existing polymers.

Cosmic-ray acceleration and escape from supernova remnants

Galactic cosmic-ray (CR) acceleration to the knee in the spectrum at a few PeV is only possible if the magnetic field ahead of a supernova remnant (SNR) shock is strongly amplified by CRs escaping the SNR. A model formulated in terms of the electric charge carried by escaping CRs predicts the maximum CR energy and the energy spectrum of CRs released into the surrounding medium. We find that historical SNRs such as Cas A, Tycho and Kepler may be expanding too slowly to accelerate CRs to the knee at the present time.

GIANT LOBES OF CENTAURUS A RADIO GALAXY OBSERVED WITH THE SUZAKU X-RAY SATELLITE

We report on Suzaku observations of selected regions within the southern giant lobe of the radio galaxy Centaurus A. In our analysis we focus on distinct X-ray features detected with the X-ray Imaging Spectrometer within the range 0.5-10 keV, some of which are likely associated with fine structure of the lobe revealed by recent high-quality radio intensity and polarization maps. With the available photon statistics, we find that the spectral properties of the detected X-ray features are equally consistent with thermal emission from hot gas with temperatures kT > 1 keV, or with a power-law radiation continuum characterized by photon indices Gamma similar to 2.0 +/- 0.5. However, the plasma parameters implied by these different models favor a synchrotron origin for the analyzed X-ray spots, indicating that a very efficient acceleration of electrons up to greater than or similar to 10 TeV energies is taking place within the giant structure of Centaurus A, albeit only in isolated and compact regions associated with extended and highly polarized radio filaments. We also present a detailed analysis of the diffuse X-ray emission filling the whole field of view of the instrument, resulting in a tentative detection of a soft excess component best fitted by a thermal model with a temperature of kT similar to 0.5 keV. The exact origin of the observed excess remains uncertain, although energetic considerations point to thermal gas filling the bulk of the volume of the lobe and mixed with the non-thermal plasma, rather than to the alternative scenario involving a condensation of the hot intergalactic medium around the edges of the expanding radio structure. If correct, this would be the first detection of the thermal content of the extended lobes of a radio galaxy in X-rays. The corresponding number density of the thermal gas in such a case is n(g) similar to 10(-4) cm(-3), while its pressure appears to be in almost exact equipartition with the volume-averaged non-thermal pressure provided by the radio-emitting electrons and the lobes' magnetic field. A prominent large-scale fluctuation of the Galactic foreground emission, resulting in excess foreground X-ray emission aligned with the lobe, cannot be ruled out. Although tentative, our findings potentially imply that the structure of the extended lobes in active galaxies is likely to be highly inhomogeneous and non-uniform, with magnetic reconnection and turbulent acceleration processes continuously converting magnetic energy to internal energy of the plasma particles, leading to possibly significant spatial and temporal variations in the plasma beta parameter around the volume-averaged equilibrium condition beta similar to 1.

Energy: lessons from devolution

Geraint Ellis and Richard Cowell explain the findings of the ‘Delivering renewable energy under devolution’ project, including some reasons for Scotland’s lead.

The UK has seen massive increases in renewable energy since 1998, with installed capacity growing from 2,600 MW to 12,300 MW in 2011. This has coincided with devolution and it is within Northern Ireland, Scotland and Wales that the greatest increases have been seen.

As devolved administrations now host half of the UK’s renewable energy capacity, their policies are critical to achieving the broader UK targets. This also provides a fascinating insight into what sort of approach works best, and why. This has been the focus of a two-year study, funded by the Economic and Social Research Council, involving universities from across the UK, which indicates that Scotland is leading the way on renewable energy.

All devolved governments have offered significant support to renewable energy but have different degrees of powers in relation to energy. Scotland’s success seems to be based on the centrality of energy issues to current political aspirations, particularly the SNP, but also has cross-party support. The research suggests that the consensus on the importance of renewable energy amongst élite interests in Scotland helps to explain why Scottish governments have been empowered and enabled to make robust use of the powers available.

As it has achieved successful growth in the sector, this too helps cultivate credibility among key business interests and gives increased leverage to its position in policy discussions with the UK Government. Scotland has been more consistent over time in presenting the expansion of renewable energy as a national economic agenda, rather than just an environmental or rural development agenda. The availability of larger, windy, but relatively less contested sites for onshore wind in Scotland has meant that more projects went through central consenting procedures rather than local planning authorities. Its enhanced support for wave and tidal power technologies is also notable. These political conditions have been harder to find in the rest of the UK, making progress a little more uncertain.

Northern Ireland has used its powers (which are more extensive than Scotland’s) to facilitate small-scale renewables and bio-fuel processes, with its liberalised planning regime offering an initial boost to expanding capacity.

This has contrasted with the position in Wales, which has least control over energy but the Welsh Government has adopted a more innovative approach to strategic spatial zoning; this appears to have pulled in a larger volume of onshore wind development interest than could be expected in a comparable region of England. A downside of the Welsh approach appears to be the fact that the concentration of these wind projects in these zones has triggered public opposition and political conflict.

It therefore appears that the powers available to the devolved governments do not seem to determine which country has been able to make greatest headway, with broader political commitments being more significant. Despite this, the research does not conclude that the actions and activities undertaken by the devolved governments are necessarily the most important factors in shaping the development of renewable energy in the UK. This is because devolution is still a relatively new dimension of energy governance in the UK and decisions affecting key drivers for renewable energy investment are still made mainly in Westminster, with the Treasury exercising close budgetary control. In all areas of the UK, grid capacity expansion remains slow to achieve. The major growth in offshore wind to date has been driven mainly by Westminster and cross-UK bodies with the most significant capacity growth being in English territorial waters.

When our thoughts are not our own: Investigating agency misattributions using the Mind-to-Mind paradigm

At the core ofthe sense ofagency for self-produced action is the sense that I, and not some other agent, am producing and directing those actions. While there is an ever-expanding body of empirical research investigating the sense of agency for bodily action, there has, to date, been little empirical investigation of the sense ofagency for thought.The present study uses the novel Mind-to-Mind paradigm, in which the agentive source of a target thought is ambiguous, to measure misattributions of agency. Seventy-two percent of participants made at least one misattribution of agency during a 5-min trial. Misattributions were significantly more frequent when the target thought was an arousing negative thought as compared to a neutral control.The findings establish a novel protocol for measuring the sense of agency for thought, and suggest that both contextual factors and emotional experience play a role in its generation.

Advances in joint modelling: A review of recent developments with application to the survival of end stage renal disease patients

The use of joint modelling approaches is becoming increasingly popular when an association exists between survival and longitudinal processes. Widely recognized for their gain in efficiency, joint models also offer a reduction in bias compared with naïve methods. With the increasing popularity comes a constantly expanding literature on joint modelling approaches. The aim of this paper is to give an overview of recent literature relating to joint models, in particular those that focus on the time-to-event survival process. A discussion is provided on the range of survival submodels that have been implemented in a joint modelling framework. A particular focus is given to the recent advancements in software used to build these models. Illustrated through the use of two different real-life data examples that focus on the survival of end-stage renal disease patients, the use of the JM and joineR packages within R are demonstrated. The possible future direction for this field of research is also discussed. © 2013 International Statistical Institute.

Environmental Affordances and Children in Post-conflict Belfast

This paper examines the experiences of children in post-conflict Belfast as peace and social change afford new opportunities at the same time as they regulate behaviours and spatial practices. Theoretically and empirically it draws on the concept of environmental affordances in order to map the experiences of 11-year-old children in separate inner-city segregated and middle-class communities. Whilst the recession has affected the pace of urban restructuring, children in the expanding mixed and largely middleclass city extract multiple advantages from their area in ways not available to segregated communities. The paper concludes by highlighting the implications for effective listening strategies in the management of divided communities. © 2011 Taylor & Francis.

Support for a possible schizophrenia vulnerability locus in region 5q22-31 in Irish families

In our genome scan for schizophrenia genes in 265 Irish pedigrees, marker D5S818 in 5q22 produced the second best result of the first 223 markers tested (P = 0.002). We then tested an additional 13 markers and the evidence suggests the presence of a vulnerability locus for schizophrenia in region 5q22-31. This region appears to be distinct from those chromosome 5 regions studied in two prior reports, but the same as that producing positive results in the report by Wildenauer and colleagues found elsewhere in this issue. The largest pairwise heterogeneity LOD (H-LOD) score was found with marker D5S393 (max 3.04, P = 0.0005), assuming a narrow phenotypic category, and a genetic model with intermediate heterozygotic liability. In marked contrast to the H-LOD scores from our sample with markers from the regions of interest on chromosomes 6p and 8p, expanding the disease definition to include schizophrenia spectrum or nonspectrum disorders produced substantially smaller scores, with a number of markers failing to yield positive values at any recombination fraction. Using multipoint H-LODS, the strongest evidence for linkage occurs under the narrow phenotypic definition and recessive genetic model, with a peak at marker D5S804 (max 3.35, P = 0.0002). Multipoint nonparametric linkage analysis produced a peak in the same location (max z = 2.84, P = 0.002) with the narrow phenotypic definition. This putative vulnerability locus appears to be segregating in 10-25% of the families studied, but this estimate is tentative. Comparison of individual family multipoint H-LOD scores at the regions of interest on chromosomes 6p, 8p and 5q showed that only a minority of families yield high lod scores in two or three regions.

Models of Mental Health

A good understanding of the different theoretical models is essential when working in the field of mental health. Not only does it help with understanding experiences of mental health difficulties and to find meaning, but it also provides a framework for expanding our knowledge of the field.

As part of the Foundations of Mental Health Practice series, this book provides a critical overview of the theoretical perspectives relevant to mental health practice. At the core of this book is the idea that no single theory is comprehensive on its own and each theory has its limitations. Divided in to two parts, Part I explores traditional models of mental health and covers the key areas: bio-medical perspectives, psychological perspectives and social perspectives, whilst Part II looks at contemporary ideas that challenge and push these traditional views. The contributions, strengths and limitations of each model are explored and, as a result, the book encourages a more holistic, open approach to understanding and responding to mental health issues.

Together, these different approaches offer students and practitioners a powerful set of perspectives from which to approach their study and careers. Each model is covered in a clear and structured way with supporting exercises and case studies. It is an essential text for anyone studying or practising in the field of mental health, including social workers, nurses and psychologists.

Aerobic oxidation catalysis with stable radicals

Selective oxidation reactions are challenging when carried out on an industrial scale. Many traditional methods are undesirable from an environmental or safety point of view. There is a need to develop sustainable catalytic approaches that use molecular oxygen as the terminal oxidant. This review will discuss the use of stable radicals (primarily nitroxyl radicals) in aerobic oxidation catalysis. We will discuss the important advances that have occurred in recent years, highlighting the catalytic performance, mechanistic insights and the expanding synthetic utility of these catalytic systems.

SN 2009N: linking normal and subluminous Type II-P Sne

We present ultraviolet, optical, near-infrared photometry and spectroscopy of SN 2009N in NGC 4487. This object is a Type II-P supernova with spectra resembling those of subluminous II-P supernovae, while its bolometric luminosity is similar to that of the intermediate-luminosity SN 2008in. We created SYNOW models of the plateau phase spectra for line identification and to measure the expansion velocity. In the near-infrared spectra we find signs indicating possible weak interaction between the supernova ejecta and the pre-existing circumstellar material. These signs are also present in the previously unpublished near-infrared spectra of SN 2008in. The distance to SN 2009N is determined via the expanding photosphere method and the standard candle method as D = 21.6 ± 1.1 Mpc. The produced nickel-mass is estimated to be ∼0.020 ± 0.004 M⊙. We infer the physical properties of the progenitor at the explosion through hydrodynamical modelling of the observables. We find the values of the total energy as ∼0.48 × 1051 erg, the ejected mass as ∼11.5 M⊙, and the initial radius as ∼287 R⊙.

Microbial community of the deep-sea brine Lake Kryos seawater-brine interface is active below the chaotropicity limit of life as revealed by recovery of mRNA

Within the complex of deep, hypersaline anoxic lakes (DHALs) of the Mediterranean Ridge, we identified a new, unexplored DHAL and named it ‘Lake Kryos’ after a nearby depression. This lake is filled with magnesium chloride (MgCl2)-rich, athalassohaline brine (salinity > 470 practical salinity units), presumably formed by the dissolution of Messinian bischofite. Compared with the DHAL Discovery, it contains elevated concentrations of kosmotropic sodium and sulfate ions, which are capable of reducing the net chaotropicily of MgCl2-rich solutions. The brine of Lake Kryos may therefore be biologically permissive at MgCl2 concentrations previously considered incompatible with life. We characterized the microbiology of the seawater–Kryos brine interface and managed to recover mRNA from the 2.27–3.03 MMgCl2 layer (equivalent to 0.747–0.631 water activity), thereby expanding the established chaotropicity window-for-life. The primary bacterial taxa present there were Kebrit Deep Bacteria 1 candidate division and DHAL-specific group of organisms, distantly related toDesulfohalobium. Two euryarchaeal candidate divisions, Mediterranean Sea Brine Lakes group 1 and halophilic cluster 1, accounted for > 85% of the rRNA-containing archaeal clones derived from the 2.27–3.03 M MgCl2 layer, but were minority community-members in the overlying interface-layers. These findings shed light on the plausibility of life in highly chaotropic environments, geochemical windows for microbial extremophiles, and have implications for habitability elsewhere in the Solar System.

The Work of Sisyphus: Squaring the Circle of Roma Recognition

Most special issues on Roma minorities want to alert readers to the devastating consequences of racist public attitudes and misdirected public policy. Here we don't shy away from such issues, but we also want to challenge our own scholarship and ask some fundamental questions about how we, as academics, are approaching such research. In this introduction the context of the special issue is explored, both in terms of the historic backdrop of an expanding European Union and the academic theoretical framework of minority integration. Major critical questioning – such as broader questions around migration, race and ethnicity discourses – are still lacking when it comes to research on or with Roma minorities. Our main aim is to move debates on from continually describing who Roma people are and what they are doing, to questioning: who defines who is Roma, when and why? What happens in policy-making, research, everyday interactions? This approach sees an understanding of recognition, representations and power dynamics as fundamental to understanding the positionings of minorities who can also be marginalised or feel disenfranchised. This introduction to the special issue highlights the importance of deeply conceptualising issues around minority integration alongside empirical knowledge of how Roma identities become implicated in and through different modalities of mobilisation. Contributions to this special issue speak to debates in minority politics and identity studies along with migration and race/ethnicity discourses. This indicates that the experiences of, and discourses surrounding Roma minorities reflect the fundamental concerns of social science research about identity, ethnicity, cohesion and change.

Accountability and its Metaphors: From Forum to Agora and Bazaar

In this paper we seek to develop a ‘relational’ perspective on accountability and on so-called ‘unaccountability.’. We focus on Mark Bovens’s use of the forum metaphor in his accountability model, arguing that his relational perspective is too narrow. We advocate instead a far broader and more fundamental engagement with the idea of relational accountability. Expanding the metaphors, we point to two other accountability spaces: ‘agora,’ a primordial accountability space and ‘bazaar,’ an emergent accountability space rooted in ground-level exchange between different actors. Assertions about ‘unaccountability,’ we argue, very often reflect a failure to appreciate the fundamentally relational nature of accountability: those who use such assertions as bases for action aimed at making situations, processes or people ‘more accountable’ in fact seek to assert or impose a certain form of relationship – one that is hierarchical and monopolistic – and reflect therefore a drive to power and domination.

STOPP/START criteria for potentially inappropriate prescribing in older people: version 2

PURPOSE: screening tool of older people's prescriptions (STOPP) and screening tool to alert to right treatment (START) criteria were first published in 2008. Due to an expanding therapeutics evidence base, updating of the criteria was required.

METHODS: we reviewed the 2008 STOPP/START criteria to add new evidence-based criteria and remove any obsolete criteria. A thorough literature review was performed to reassess the evidence base of the 2008 criteria and the proposed new criteria. Nineteen experts from 13 European countries reviewed a new draft of STOPP & START criteria including proposed new criteria. These experts were also asked to propose additional criteria they considered important to include in the revised STOPP & START criteria and to highlight any criteria from the 2008 list they considered less important or lacking an evidence base. The revised list of criteria was then validated using the Delphi consensus methodology.

RESULTS: the expert panel agreed a final list of 114 criteria after two Delphi validation rounds, i.e. 80 STOPP criteria and 34 START criteria. This represents an overall 31% increase in STOPP/START criteria compared with version 1. Several new STOPP categories were created in version 2, namely antiplatelet/anticoagulant drugs, drugs affecting, or affected by, renal function and drugs that increase anticholinergic burden; new START categories include urogenital system drugs, analgesics and vaccines.

CONCLUSION: STOPP/START version 2 criteria have been expanded and updated for the purpose of minimizing inappropriate prescribing in older people. These criteria are based on an up-to-date literature review and consensus validation among a European panel of experts.