Leggett-Garg inequalities for the statistics of electron transport

We derive a set of Leggett-Garg inequalities (temporal Bell's inequalities) for the moment generating function of charge transferred through a conductor. Violation of these inequalities demonstrates the absence of a macroscopic-real description of the transport process. We show how these inequalities can be violated by quantum-mechanical systems and consider transport through normal and superconducting single-electron transistors as examples.Comment: 5 pages; 3 figure

One-by-one trap activation in silicon nanowire transistors

Flicker or 1/f noise in metal-oxide-semiconductor field-effect transistors (MOSFETs) has been identified as the main source of noise at low frequency. It often originates from an ensemble of a huge number of charges trapping and detrapping. However, a deviation from the well-known model of 1/f noise is observed for nanoscale MOSFETs and a new model is required. Here, we report the observation of one-by-one trap activation controlled by the gate voltage in a nanowire MOSFET and we propose a new low-frequency-noise theory for nanoscale FETs. We demonstrate that the Coulomb repulsion between electronically charged trap sites avoids the activation of several traps simultaneously. This effect induces a noise reduction by more than one order of magnitude. It decreases when increasing the electron density in the channel due to the electrical screening of traps. These findings are technologically useful for any FETs with a short and narrow channel.Comment: One file with paper and supplementary informatio

Enhanced shot noise in resonant tunnelling via interacting localised states

In a variety of mesoscopic systems shot noise is seen to be suppressed in comparison with its Poisson value. In this work we observe a considerable enhancement of shot noise in the case of resonant tunnelling via localised states. We present a model of correlated transport through two localised states which provides both a qualitative and quantitative description of this effect.Comment: 4 pages, 4 figure

Peptide ligands of the cardiac ryanodine receptor as super-resolution imaging probes

To study the structural basis of pathological remodelling and altered calcium channel functional states in the heart, we sought to re-purpose high-affinity ligands of the cardiac calcium channel, the ryanodine receptor (RyR2), into super-resolution imaging probes. Imperacalcin (IpCa), a scorpion toxin peptide which induces channel sub-conduction states, and DPc10, a synthetic peptide corresponding to a sequence of the RyR2, which replicates arrhythmogenic CPVT functional changes, were used in fluorescent imaging experiments. Isolated adult rat ventricular cardiomyocytes were saponin-permeabilised and incubated with each peptide. IpCa-A546 became sequestered into the mitochondria. This was prevented by treatment of the permeabilised cells with the ionophore FCCP, revealing a striated staining pattern in confocal imaging which had weak colocalisation with RyR2 clusters. Poor specificity (as an RyR2 imaging probe) was confirmed at higher resolution with expansion microscopy (proExM) (~70 nm). DPc10-FITC labelled a striated pattern, which had moderate colocalisation with RyR2 cluster labelling in confocal and proExM. There was also widespread non-target labelling of the Z-discs, intercalated discs, and nuclei, which was unaffected by incubation times or 10 mM caffeine. The inactive peptide mut-DPc10-FITC (which causes no functional effects) displayed a similar labelling pattern. Significant labelling of structures unrelated to RyR2 by both peptide conjugates makes their use as highly specific imaging probes of RyR2 in living isolated cardiomyocytes highly challenging. We investigated the native DPc10 sequence within the RyR2 structure to understand the domain interactions and proposed mechanism of peptide binding. The native DPc10 sequence does not directly interact with another domain, and but is downstream of one such domain interface. The rabbit Arg2475 (equivalent to human Arg2474, mutated in CPVT) in the native sequence is the most accessible portion and most likely location for peptide disturbance, suggesting FITC placement does not impact peptide binding

Women take care and men take charge’: The case of leadership and gender in the Public and Commercial Services Union

This article presents the findings of a case study that aimed to understand the specific leadership styles that are valued by women and men lay representatives in the Public and Commercial Services (PCS) union and to determine the gendered implications for increasing women’s leadership and representation in trade unions. Survey responses from PCS lay representatives (reps) show the majority of women and men agreed that the leadership style they value, and makes a good union leader, is post-heroic (communal) leadership. This approach is associated with leadership characteristics such as being helpful, sensitive, and kind and are generally practised by women. This contrasts with male union leaders who are associated with a traditional, heroic (agentic) leadership style characterised by confidence, self-reliance, and decisiveness. Although some differences exist that highlight gender issues, both women and men lay reps have positive attitudes towards increasing women’s representation and participation in union leadership

Probation migration(s): Examining occupational culture in a turbulent field

In June 2014 approx. 54 per cent of the total probation service workforce in England and Wales were transferred to the newly created Community Rehabilitation Companies (CRCs) as part of the government’s plans to establish a market for offender management services. This marked the beginning of one of the largest and most significant migrations of criminal justice staff from the public to the private sector in England and Wales. This article presents findings from an ethnographic study of the formation of one of these CRCs through to the period immediately following the transfer into private ownership. The authors discuss the key features of this migration which are identified as ‘splitting and fracturing’, ‘adapting and forming’ and ‘exiting or accommodation’. It is contended that this development not only has significant implications for the future of probation services but also provides a unique example of the impact on an occupational culture of migration from the public to the private sector

Leaders’ orientations to diversity: two cases from education

This article explores two case colleges in England to consider how context, conceptualisation, orientation and action interact in relation to diversity issues in leader ship. Focus group and individual interview data are analysed. Context is perceived as influential in shaping concepts and action. In one case, the diversity and socio-economic disadvantage of the community create a perceived imperative to address diversity, resulting in multiple conceptions of diversity and systemic action. In the second case, the context of a perceived homogeneous community interacts with an equal opportunities conceptualization of diversity to justify little or no action. A tentative theoretical model is suggested to frame further enquir

Racism, anti-racist practice and social work: articulating the teaching and learning experiences of Black social workers

In the mid 1990s a Black practice teacher programme was established in Manchester and Merseyside with the primary aim to increase the number of Black practice teachers in social work organisations, and in turn provide a supportive and encouraging learning environment for Black student social workers whilst on placement. In the north‐west of England research has been undertaken, to establish the quality of the practice teaching and student learning taking place with Black practice teachers and students. This paper is an exploration of the ideas generated within the placement process that particularly focused on the discourse of racism and ant‐racist practice. Black students and practice teachers explain their understanding of racism and anti‐racist practice within social work. From the research, the paper will critique some of the ideas concerning anti‐racism. In particular, it will question whether anti‐racist social work practice needs to be re‐evaluated in the light of a context with new migrants, asylum seekers and refugees. It will concluded, by arguing that whilst the terms anti‐racism, Black and Minority Ethnic have resonance as a form of political strategic essentialism, it is important to develop more positive representations in the future

Manageable creativity

This article notes a perception in mainstream management theory and practice that creativity has shifted from being disruptive or destructive to 'manageable'. This concept of manageable creativity in business is reflected in a similar rhetoric in cultural policy, especially towards the creative industries. The article argues that the idea of 'manageable creativity' can be traced back to a 'heroic' and a 'structural' model of creativity. It is argued that the 'heroic' model of creativity is being subsumed within a 'structural' model which emphasises the systems and infrastructure around individual creativity rather than focusing on raw talent and pure content. Yet this structured approach carries problems of its own, in particular a tendency to overlook the unpredictability of creative processes, people and products. Ironically, it may be that some confusion in our policies towards creativity is inevitable, reflecting the paradoxes and transitions which characterise the creative process

Sexual harassment in an east African agribusiness supply chain

This article discusses sexual harassment in the east African cut-flower and horticultural industry, based on research on 62 farms in Ethiopia, Kenya, Tanzania and Uganda. It argues that sexual harassment is fostered both by coercive labour conditions within global value chains and by existing hierarchical gender relations. The research finds that harassment is widespread, that many lack a vocabulary to describe or discuss this, and that female casual and temporary workers are most likely to be targeted. Action research coupled with organisation of workers, however, has been effective in giving ‘voice’ to those suffering harassment: this is a first step in a feminist labour mobilisation and policy formulation. Procedures against sexual harassment are beginning to be formulated: a key concern is implementation. Addressing sexual harassment is central in ensuring the security of working people, particularly the most marginalised