Sources of negative tunneling magneto-resistance in multilevel quantum dots with ferromagnetic contacts

We analyze distinct sources of spin-dependent energy level shifts and their impact on the tunneling magnetoresistance (TMR) of interacting quantum dots coupled to collinearly polarized ferromagnetic leads. Level shifts due to virtual charge fluctuations can be quantitatively evaluated within a diagrammatic representation of our transport theory. The theory is valid for multilevel quantum dot systems and we exemplarily apply it to carbon nanotube quantum dots, where we show that the presence of many levels can qualitatively influence the TMR effect.Comment: 4 pages, 2 figures, supplemental materia

Novel Approaches towards Highly Selective Self-Powered Gas Sensors

The prevailing design approaches of semiconductor gas sensors struggle to overcome most of their current limitations such as poor selectivity, and high power consumption. Herein, a new sensing concept based on devices that are capable of detecting gases without the need of any external power sources required to activate interaction of gases with sensor or to generate the sensor read out signal. Based on the integration of complementary functionalities (namely; powering and sensing) in a singular nanostructure, self-sustained gas sensors will be demonstrated. Moreover, a rational methodology to design organic surface functionalization that provide high selectivity towards single gas species will also be discussed. Specifically, theoretical results, confirmed experimentally, indicate that precisely tuning of the sterical and electronic structure of sensor material/organic interfaces can lead to unprecedented selectivity values, comparable to those typical of bioselective processes. Finally, an integrated gas sensor that combine both the self-powering and selective detection strategies in one single device will also be presented. © 2015 Published by Elsevier Ltd.Peer ReviewedPostprint (published version

The low energy spectrum of finite size metallic SWNTs

The electronic spectrum of metallic finite-size single-wall carbon nanotubes at low energies is derived. It is based on a tight-binding description for the interacting p_{z} electrons. Not only the forward scattering parts of the Coulomb interaction, which are diagonalized by bosonization, are considered, but also all other processes becoming relevant for small diameter tubes. As a consequence of the substructure of the underlying lattice, a spin 1 triplet is found as ground state if the exchange splitting is larger than the branch mismatch, a spin 0 singlet otherwise. Moreover the excitation spectrum is calculated

World caf\ue9 method to engage smart energy-district project partners in assessing urban co-benefits

Urban energy-district projects introduce outstanding technological innovation in buildings and energy systems increasing sustainability in city neighborhoods. Such projects generate additional co-benefits for the city beyond changes in physical elements and development of social and institutional relationships (e.g. local employment, environmental quality, public health, property values, innovation attitude, etc.). Since exceeding main declared goals or not always clearly foreseen in the early project phase, these co-benefits are often not properly understood and considered. However, only their explicit recognition will make possible their inclusion in the assessment of the whole project\u2019s performance. From these considerations, this study faces the issue of engaging project partners in assessing co-benefits in order to consider a broad spectrum of relevant, positive effects in the evaluation process. Group knowledge and group thinking of this complex topic are investigated through the world caf\ue9 method, providing an atmosphere of trust and open discussions among participants. This empirical work lays the foundations to go beyond the mere economic measure as the sole criterion for assessing project effects, also including changes in end-user behavior and intangible asset

Could hair-lichens of high-elevation forests help detect the impact of global change in the Alps?

Climate change and the anthropic emission of pollutants are likely to have an accelerated impact in high-elevation mountain areas. This phenomenon could have negative consequences on alpine habitats and for species of conservation in relative proximity to dense human populations. This premise implies that the crucial task is in the early detection of warning signals of ecological changes. In alpine landscapes, high-elevation forests provide a unique environment for taking full advantage of epiphytic lichens as sensitive indicators of climate change and air pollution. This literature reviewis intended to provide a starting point for developing practical biomonitoring tools that elucidate the potential of hair-lichens, associated with high-elevation forests, as ecological indicators of global change in the European Alps. We found support for the practical use of hair-lichens to detect the impact of climate change and nitrogen pollution in high-elevation forest habitats. The use of these organisms as ecological indicators presents an opportunity to expand monitoring activities and develop predictive tools that support decisions on how to mitigate the effects of global change in the Alps

A synthesis: what works to deliver optimal health outcomes for uk care home residents

The detailed reviews, interviews and subsequent longitudinal case studies structured around a unifying realist analytical framework allowed us to establish a theory of commissioning for health care provision to care homes which proposes health services will work better when: staff are explicitly tasked to work with care homes at an institutional level as well as individual residents; healthcare and care home staff are empowered to co-design their working models; where explicit expertise in dementia care is available; the role of GP as a medical care provider is supported by access to a wider array of services; and they incorporate care management. There was no evidence from our study that a short term focus on avoiding admissions to acute hospitals from care homes added any value to service specification or care delivery

Young onset dementia: Public involvement in co-designing community-based support

Whilst the support requirements of people diagnosed with young onset dementia are well-documented, less is known about what needs to be in place to provide age-appropriate care. To understand priorities for service planning and commissioning and to inform the design of a future study of community-based service delivery models, we held two rounds of discussions with four groups of people affected by young onset dementia (n = 31) and interviewed memory services (n = 3) and non-profit service providers (n = 7) in two sites in England. Discussions confirmed published evidence on support requirements, but also reframed priorities for support and suggested new approaches to dementia care at the community level. This paper argues that involving people with young onset dementia in the assessment of research findings in terms of what is important to them, and inviting suggestions for solutions, provides a way for co-designing services that address the challenges of accessing support for people affected by young onset dementia

Division of Giardia isolates from humans into two genetically distinct assemblages by electrophoretic analysis of enzyme encoded at 27 loci in comparison with Giardia muris

Giardia that infect humans are known to be heterogeneous but they are assigned currently to a single species, Giardia intestinalis (syn. G. lamblia). The genetic differences that exist within G. intestinalis have not yet been assessed quantitatively and neither have they been compared in magnitude with those that exist between G. intestinalis and species that are morphologically similar (G. duodenalis) or morphologically distinct (e.g. G. muris). In this study, 60 Australian isolates of G. intestinalis were analysed electrophoretically at 27 enzyme loci and compared with G. muris and a feline isolate of G. duodenalis. Isolates of G. intestinalis were distinct genetically from both G. muris (approximately 80% fixed allelic differences) and the feline G. duodenalis isolate (approximately 75% fixed allelic differences). The G. intestinalis isolates were extremely heterogeneous but they fell into 2 major genetic assemblages, separated by fixed allelic differences at approximately 60% of loci examined. The magnitude of the genetic differences between the G. intestinalis assemblages approached the level that distinguished the G. duodenalis isolate from the morphologically distinct G. muris. This raises important questions about the evolutionary relationships of the assemblages with Homo sapiens, the possibility of ancient or contemporary transmission from animal hosts to humans and the biogeographical origins of the two clusters.G. Mayrhofer, R. H. Andrews, P. L. Ey and N. B. Chilto