Enabling QM-accurate simulation of dislocation motion in γ−Ni and α−Fe using a hybrid multiscale approach

We present an extension of the ‘learn on the fly’ method to the study of the motion of dislocations in metallic systems, developed with the aim of producing information-efficient force models that can be systematically validated against reference QM calculations. Nye tensor analysis is used to dynamically track the quantum region centered at the core of a dislocation, thus enabling quantum mechanics/molecular mechanics simulations. The technique is used to study the motion of screw dislocations in Ni-Al systems, relevant to plastic deformation in Ni-based alloys, at a variety of temperature/strain conditions. These simulations reveal only a moderate spacing ( ∼ 5 Å ) between Shockley partial dislocations, at variance with the predictions of traditional molecular dynamics (MD) simulation using interatomic potentials, which yields a much larger spacing in the high stress regime. The discrepancy can be rationalized in terms of the elastic properties of an hcp crystal, which influence the behavior of the stacking fault region between Shockley partial dislocations. The transferability of this technique to more challenging systems is addressed, focusing on the expected accuracy of such calculations. The bcc α − Fe phase is a prime example, as its magnetic properties at the open surfaces make it particularly challenging for embedding-based QM/MM techniques. Our tests reveal that high accuracy can still be obtained at the core of a dislocation, albeit at a significant computational cost for fully converged results. However, we find this cost can be reduced by using a machine learning approach to progressively reduce the rate of expensive QM calculations required during the dynamical simulations, as the size of the QM database increases

Community beliefs about treatments and outcomes of mental disorders: A mental health literacy survey in a rural area of Maharashtra, India

Objectives: Mental health remains a neglected issue in most developing countries, especially in rural areas where access to effective mental health services is limited. The integration of mental health into primary health care is being promoted as a strategy to address this problem. Consequently, there is an urgent need to enhance mental health awareness among communities, and to provide mental health training for primary healthcare staff. In order to do this effectively, it is important to understand and take account of local views on mental health and illness. As such, a mental health literacy (MHL) assessment was undertaken in a poor, rural area of Maharashtra, India to inform the development of a mental health training programme. Study design: A cross-sectional MHL survey was undertaken in late 2007. Methods: Data were collected from 240 systematically sampled community members and 60 purposively sampled village health workers (VHWs) using an interviewer-administered questionnaire. Participants were presented with two vignettes describing people experiencing symptoms of mental disorders (depression, psychosis), and were asked to name the problems, and to identify the treatments and people that were most likely to be helpful (or otherwise), and the likely outcomes for people with such problems. Results: Most participants recognized that the people in the vignettes were experiencing a mental health problem. 'Depression' was the most common label for the problems experienced in the depression vignette, and 'a mind/brain problem' was the most common label in the case of the psychosis vignette. Socio-economic interventions provided by family, friends and neighbours were considered to be most helpful. Local VHWs and doctors were also viewed as potentially helpful, but psychiatrists less so. Approximately half of the sample thought that dealing with the problem alone would be helpful. Special diets, tonics, appetite stimulants and sleeping pills were also strongly endorsed, but awareness of psychiatric medications was negligible. Conclusion: The findings from this study highlight the need to enhance MHL in this community. Additionally, there is a need to build the capacity of the primary healthcare staff, including the VHWs, so that they are equipped to provide an effective local response for people experiencing mental health problems

Attitudes to people with mental disorders: a mental health literacy survey in a rural area of Maharashtra, India

Introduction: People with mental disorders experience discrimination as a consequence of stigmatising attitudes that are largely socio-culturally constructed. Thus, there is a need to understand local contexts in order to develop effective programs to change such attitudes. We undertook a mental health literacy survey in rural Maharashtra, India, prior to developing a mental health training program for village health workers (VHWs) in a primary health care setting. Methods: A cross-sectional mental health literacy survey was undertaken in late 2007, which involved interviewer-administration of a questionnaire to 240 systematically sampled community members, and 60 purposively sampled VHWs. Participants were presented with two vignettes describing people experiencing symptoms of mental disorders (depression, psychosis), and were asked about attitudes towards, and desired social distance from, the people in the vignettes (the latter being a proxy measure for stigma). Linear regression modelling was undertaken to identify predictors of social distance. Results: Although the community was relatively accepting of people with mental disorders, false beliefs and negative attitudes were still evident. Desired social distance was consistently greater for the person depicted in the psychosis vignette compared to the depression vignette. For both vignettes, the main predictor of greater social distance was perceiving the person as dangerous, and the predictors of reduced social distance were being a VHW, and seeing the problem as a sign of personal weakness. For depression, believing the cause to be family tensions also reduced social distance. For psychosis, labelling the disorder as a mind/brain problem, and believing the cause to be lack of control over life or genetic factors increased social distance. The vast majority did not agree that the problems experienced in the vignettes were 'a real medical illness'. Conclusion: Promoting bio-medical explanations for mental disorders in this setting may exacerbate discriminatory attitudes. Provision of contextually relevant mental health training for the VHWs so that they are able to communicate, model and shape more positive attitudes is the next step

A mental health training program for community health workers in India: impact on knowledge and attitudes

<p>Abstract</p> <p>Background</p> <p>Unmet needs for mental health treatment in low income countries are pervasive. If mental health is to be effectively integrated into primary health care in low income countries like India then grass-roots workers need to acquire relevant knowledge and skills to be able to recognise, refer and support people experiencing mental disorders in their own communities. This study aims to provide a mental health training intervention to community health workers in Bangalore Rural District, Karnataka, India, and to evaluate the impact of this training on mental health literacy.</p> <p>Methods</p> <p>A pre-test post-test study design was undertaken with assessment of mental health literacy at three time points; baseline, completion of the training, and three month follow-up. Mental health literacy was assessed using the interviewer-administered Mental Health Literacy Survey. The training intervention was a four day course based on a facilitator's manual developed specifically for community health workers in India.</p> <p>Results</p> <p>70 community health workers from Doddaballapur, Bangalore Rural District were recuited for the study. The training course improved participants' ability to recognize a mental disorder in a vignette, and reduced participants' faith in unhelpful and potentially harmful pharmacological interventions. There was evidence of a minor reduction in stigmatizing attitudes, and it was unclear if the training resulted in a change in participants' faith in recovery following treatment.</p> <p>Conclusion</p> <p>The findings from this study indicate that the training course demonstrated potential to be an effective way to improve some aspects of mental health literacy, and highlights strategies for strengthening the training course.</p

Understanding and mitigating hydrogen embrittlement of steels: a review of experimental, modelling and design progress from atomistic to continuum

Hydrogen embrittlement is a complex phenomenon, involving several length- and timescales, that affects a large class of metals. It can significantly reduce the ductility and load-bearing capacity and cause cracking and catastrophic brittle failures at stresses below the yield stress of susceptible materials. Despite a large research effort in attempting to understand the mechanisms of failure and in developing potential mitigating solutions, hydrogen embrittlement mechanisms are still not completely understood. There are controversial opinions in the literature regarding the underlying mechanisms and related experimental evidence supporting each of these theories. The aim of this paper is to provide a detailed review up to the current state of the art on the effect of hydrogen on the degradation of metals, with a particular focus on steels. Here, we describe the effect of hydrogen in steels from the atomistic to the continuum scale by reporting theoretical evidence supported by quantum calculation and modern experimental characterisation methods, macroscopic effects that influence the mechanical properties of steels and established damaging mechanisms for the embrittlement of steels. Furthermore, we give an insight into current approaches and new mitigation strategies used to design new steels resistant to hydrogen embrittlement

IgG 3 + B cells are associated with the development of multiple sclerosis

Objectives Disease‐modifying therapies (DMTs) targeting B cells are amongst the most effective for preventing multiple sclerosis (MS) progression. IgG3 antibodies and their uncharacterised B‐cell clones are predicted to play a pathogenic role in MS. Identifying subsets of IgG3+ B cells involved in MS progression could improve diagnosis, could inform timely disease intervention and may lead to new DMTs that target B cells more specifically. Methods We designed a 31‐parameter B‐cell‐focused mass cytometry panel to interrogate the role of peripheral blood IgG3+ B cells in MS progression of two different patient cohorts: one to investigate the B‐cell subsets involved in conversion from clinically isolated syndrome (CIS) to MS; and another to compare MS patients with inactive or active stages of disease. Each independent cohort included a group of non‐MS controls. Results Nine distinct CD20+IgD−IgG3+ B‐cell subsets were identified. Significant changes in the proportion of CD21+CD24+CD27−CD38− and CD27+CD38hiCD71hi memory B‐cell subsets correlated with changes in serum IgG3 levels and time to conversion from CIS to MS. The same CD38− double‐negative B‐cell subset was significantly elevated in MS patients with active forms of the disease. A third CD21+CD24+CD27+CD38− subset was elevated in patients with active MS, whilst narrowband UVB significantly reduced the proportion of this switched‐memory B‐cell subset. Conclusion We have identified previously uncharacterised subsets of IgG3+ B cells and shown them to correlate with autoimmune attacks on the central nervous system (CNS). These results highlight the potential for therapies that specifically target IgG3+ B cells to impact MS progression

Narrative and Interpretation on Twitter: Reading tweets by telling stories

Existing research on communication on Twitter has largely ignored the question of how users make sense of the fragmentary tweets with which they are presented. Focusing on the use of Twitter for political reporting in post-revolutionary Egypt, this article argues that the production of mental stories provides readers with a mechanism for interpreting the meaning of individual tweets in terms of their relationships to other material. Drawing on contemporary narratology, it argues that Twitter exhibits key elements of narrativity, but that a creative reading process is nonetheless required to transform this incipient narrativity into coherent, sense-making mental narratives. This foregrounding of the reader’s creative role makes stories on Twitter highly fluid and dynamic. Through reference to classic critical theory, I propose that this nonetheless represents an evolution rather than a radical break from earlier forms of narrative reception, which in many cases demanded similarly creative reading practices

Global social theory: building resources

There has been an intensification of student protests around the world addressing issues of racial exclusion and racialised hierarchy within the university, including its teaching and research practices. These movements point to urgent concerns about what and how we teach and research, and how the resources of universities might be used to support the amelioration of injustice rather than its reproduction. This short piece focuses on the curriculum and points to actions that we can take to build resources for a more dynamic and adequate curriculum within our universities. In particular, it discusses one collaborative initiative that all the authors have been involved in, the website Global Social Theory. This site provides resources for the diversification and expansion of the curriculum for those teaching and studying social theory

Tapping culture collections for fungal endophytes: first genome assemblies for three genera and five species in the Ascomycota

The Ascomycota form the largest phylum in the fungal kingdom and show a wide diversity of lifestyles, some involving associations with plants. Genomic data are available for many ascomycetes that are pathogenic to plants, but endophytes, which are asymptomatic inhabitants of plants, are relatively understudied. Here, using short- and long-read technologies, we have sequenced and assembled genomes for 15 endophytic ascomycete strains from CABI’s culture collections. We used phylogenetic analysis to refine the classification of taxa, which revealed that 7 of our 15 genome assemblies are the first for the genus and/or species. We also demonstrated that cytometric genome size estimates can act as a valuable metric for assessing assembly “completeness”, which can easily be overestimated when using BUSCOs alone and has broader implications for genome assembly initiatives. In producing these new genome resources, we emphasise the value of mining existing culture collections to produce data that can help to address major research questions relating to plant–fungal interactions