Ab-initio theory of metal-insulator interfaces in a finite electric field

We present a novel technique for calculating the dielectric response of metal/insulator heterostructures. This scheme allows, for the first time, the fully first-principles calculation of the microscopic properties of thin-film capacitors at finite bias potential. The method can be readily applied to pure insulators, where it provides an interesting alternative to conventional finite-field techniques based on the Berry-phase formalism. We demonstrate the effectiveness of our method by performing comprehensive numerical tests on a model Ag/MgO/Ag heterostructure.Comment: 10 pages, 5 figures, major revisio

Italophilia meets Albanophobia: paradoxes of asymmetric assimilation and identity processes amongst Albanian immigrants in Italy

This paper discusses what we call the 'Albanian assimilation paradox'. Since arrival in 1991, Albanians have become one of the most 'integrated' of all non-EU immigrant groups in Italy, based on their knowledge of Italian, geographical dispersion, balanced demography, employment progress, and desire to remain in Italy. Yet they are the nationality most rejected and stigmatised by Italians – stereotyped as criminals, prostitutes and uncivilised people. Based on 97 interviews with Albanians in three cities in Italy, we explore the multifaceted dimensions of their patchy assimilation. Although the hegemonic negative framing of Albanians by Italian media and public discourse plays a major role, other elements of the picture relate to Albanians' complexly shifting identities, framed both against and within this discourse (and hence both resisting and internalising it), and against changing concepts of Albanian national and diasporic identities derived from ambiguous perceptions of the national homeland

Accurate polarization within a unified Wannier function formalism

We present an alternative formalism for calculating the maximally localized Wannier functions in crystalline solids, obtaining an expression which is extremely simple and general. In particular, our scheme is exactly invariant under Brillouin zone folding, and therefore it extends trivially to the Gamma-point case. We study the convergence properties of the Wannier functions, their quadratic spread and centers as obtained by our simplified technique. We show how this convergence can be drastically improved by a simple and inexpensive ``refinement'' step, which allows for very efficient and accurate calculations of the polarization in zero external field.Comment: 9 pages, 4 figure

A textile-based platform for real-time sweat collection and analysis

The ability to perform real-time chemical measurements of body fluids is an exciting concept for the healthcare sector and the sports industry. This work is part of the BIOTEX project, an EU FP6 project which involved the development of textile-based sensors to measure the chemical composition of sweat. This is a challenging task involving the collection of sweat samples, delivery to an active surface and the removal of waste products. A textile based platform which would be in immediate contact with the skin was developed for this purpose. The system uses capillary action and exhibits a passive pumping mechanism. This is achieved by using a combination of moisture wicking fabric and a highly absorbent material. A fabric channel is created for the integration of sensors. The channel is produced using a mask and screen-printing hydrophobic material onto the fabric. Different channel lengths and widths affect the flow rate of the system. The channel dimensions were designed based on typical sweat rates and also to accommodate sensor placement. A textile patch was developed and integrated into a waistband for collection of sweat on the lower back. Real-time measurements of sweat pH, sodium concentration, conductivity and temperature were measured during exercise using the textile patch

Informing and improving policy and practice for carers through research and evaluation

Carers Week took place last week to raise awareness and improve the lives of carers and the people they care for. Much has been said about the need for a robust evidence base to support this aim. Last year a seminar series funded by the Economic and Social Care Research Council explored some of the evidence and next steps; and there is a growing body of studies exploring different aspects of carers’ lives. Here PSSRU at LSE colleagues Valentina Zigante, Nicola Brimblecombe, and Derek King reflect on a joint workshop by the Social Services Research Group and the NIHR School for Social Care Research on how research and evaluation could inform and improve policy and practice in relation to informal carers

Influence of strain and oxygen vacancies on the magnetoelectric properties of multiferroic bismuth ferrite

The dependencies on strain and oxygen vacancies of the ferroelectric polarization and the weak ferromagnetic magnetization in the multiferroic material bismuth ferrite, BiFeO_3, are investigated using first principles density functional theory calculations. The electric polarization is found to be rather independent of strain, in striking contrast to most conventional perovskite ferroelectrics. It is also not significantly affected by oxygen vacancies, or by the combined presence of strain and oxygen vacancies. The magnetization is also unaffected by strain, however the incorporation of oxygen vacancies can alter the magnetization slightly, and also leads to the formation of Fe^{2+}. These results are discussed in light of recent experiments on epitaxial films of BiFeO_3 which reported a strong thickness dependence of both magnetization and polarization.Comment: 9 pages, 3 figure

Barriers to receipt of social care services for working carers and the people they care for in times of austerity

Reconciliation of unpaid care and employment is an increasingly important societal, economic and policy issue, both in the UK and internationally. Previous research shows the effectiveness of formal social care services in enabling carers to remain in employment. Using quantitative and qualitative data collected from carers and the person they care for in 2013 and 2015, during a period of cuts to adult social care in England, we explore barriers experienced to receipt of social care services. The main barriers to receipt of services identified in our study were availability, characteristics of services such as quality, and attitudes of carer and care-recipient to receiving services. These barriers have particular implications for carers' ability to reconcile care and employment

Perceptions of unmet needs for community social care services in England. A comparison of working carers and the people they care for

Previous UK research has found expressed unmet need for services by unpaid working carers and among disabled and older people. There are, however, suggestions from research that views on unmet needs for services differ between carers and care-recipients. Working carers in the UK say that the care-recipient is sometimes reluctant to accept services and the few international comparative dyad studies that have been carried out find that carers perceive higher unmet need than care-recipients. Recent policy discussions in England have also recognised that there may be differences of opinion. We collected data in 2013 from working carer/care-recipient dyads in England about perceived need for services for the care-recipient, disability, unpaid care hour provision and individual and socio-demographic characteristics. We find that care-recipients as well as their carers perceive high unmet need for services, although carers perceive higher unmet need. For carers, unmet need is associated with the disability of the carer-recipient and being the daughter or son of the care-recipient; for care recipients it is associated with unpaid care hours, carers’ employment status and carers’ health. The majority of dyads agree on need for services, and agreement is higher when the working carer provides care for 10 hours or more hours a week. Services for care-recipients may enable working carers to remain in employment so agreement on needs for services supports the implementation of legislation, policy and practice that has a duty to, or aims to, support carer’s employment

Numbers of working carers whose employment is 'at risk' in England

Recent evidence suggests that a key threshold at which carers in England are at risk of leaving employment occurs when unpaid care is provided for 10 or more hours a week, a lower threshold than previously thought. Previous studies had shown that providing care for 20 or more hours a week had a negative effect on employment. One implication is that there are more working carers whose employment is at risk than previously thought. This paper aims to estimate the numbers of working carers whose employment is at risk because they provide care for 10 or more hours a week. A subsidiary aim is to estimate the numbers of working carers providing care for 10 or more hours a week to someone in a private household. Using the 2011 Population Census, Understanding Society (2010/11) and the Survey of Carers in Households (2009/10), we find that there are approximately 790,000 working carers aged 16-64 whose employment is at risk because they provide care for 10 or more hours a week. Of these, approximately 735,000 provide care to someone in a private household. There are nearly a quarter of a million more carers whose employment is at risk than previously thought