Dispersion interactions between semiconducting wires

The dispersion energy between extended molecular chains (or equivalently infinite wires) with non-zero band gaps is generally assumed to be expressible as a pair-wise sum of atom-atom terms which decay as $R^{-6}$. Using a model system of two parallel wires with a variable band gap, we show that this is not the case. The dispersion interaction scales as $z^{-5}$ for large interwire separations $z$, as expected for an insulator, but as the band gap decreases the interaction is greatly enhanced; while at shorter (but non-overlapping) separations it approaches a power-law scaling given by $z^{-2}$, \emph{i.e.} the dispersion interaction expected between \emph{metallic} wires. We demonstrate that these effects can be understood from the increasing length scale of the plasmon modes (charge fluctuations), and their increasing contribution to the molecular dipole polarizability and the dispersion interaction, as the band gaps are reduced. This result calls into question methods which invoke locality assumptions in deriving dispersion interactions between extended small-gap systems.Comment: 8 pages, 5 figure

The Role of Technology Support Centres in stimulating Entrepreneurship and Innovation in SME Clusters

The Innovative Product Development Centre (IPDC) was established at the University of Wolverhampton in the West Midlands region of the UK with a mission “to help small and medium sized companies improve their business, secure jobs and contribute to the economic regeneration of the West Midlands Region”. Since 2000, the IPDC has helped several hundred enterprises to develop their businesses through innovation and new product development. Demand for help is high, which reflects a healthy desire by the SMEs to innovate. The assistance given is time limited, but its impact on the business is extremely varied. This paper will discuss the role that a university based product development and technology centre can play in supporting a regional agenda for developing entrepreneurship and innovation in SMEs. Using case studies drawn from the experiences of working with SMEs from the West Midlands region, the paper will consider key issues such as: • Entrepreneurial leadership in SMEs • Formalised approaches for managing NPD • Technology support for innovation • Product innovation • Business networks and entrepreneurial clusters The paper will conclude that university based centres like IPDC can play a vital role in regional development programmes by helping minimise the risks for entrepreneurs to develop new products or adopt new process technologies. Importantly, investments in such centres by regional development agencies can be pivotal for stimulating access to new technology for the exploitation of entrepreneurial clusters and creating attractive inward investment opportunities

Completing NLO QCD Corrections for Tree Level Non-Leptonic Delta F = 1 Decays Beyond the Standard Model

In various extensions of the Standard Model (SM) tree level non-leptonic decays of hadrons receive contributions from new heavy gauge bosons and scalars. Prominent examples are the right-handed W' bosons in left-right symmetric models and charged Higgs (H^\pm) particles in models with extended scalar sector like two Higgs doublet models and supersymmetric models. Even in the case of decays with four different quark flavours involved, to which penguin operators cannot contribute, twenty linearly independent operators, instead of two in the SM, have to be considered. Anticipating the important role of such decays at the LHCb, KEKB and Super-B in Rome and having in mind future improved lattice computations, we complete the existing NLO QCD formulae for these processes by calculating O(alpha_s) corrections to matching conditions for the Wilson coefficients of all contributing operators in the NDR-\bar{MS} scheme. This allows to reduce certain unphysical scale and renormalization scheme dependences in the existing NLO calculations. Our results can also be applied to models with tree-level heavy neutral gauge boson and scalar exchanges in Delta F = 1 transitions and constitute an important part of NLO analyses of those non-leptonic decays to which also penguin operators contribute.Comment: 24 pages, 6 figure

Sport as a privilege in Spain

The reduction of Physical Education hours in the Spanish curriculum originates from a false premise: families are already aware of the importance of physical activity, and attempt to compensate for the lack of it at school with an extra schedule. It seems then, that there is an assumption that classes that are available after school are only related to physical activity: this is not the case. Furthermore, only those families that are fully aware of the consequences of their children’s inactivity, and who can (and want to) invest in those extra classes and engage in some kind of physical activity after school. But the reality is that Physical activity only is important for some families

Breast tumor kinase (Brk/PTK6) plays a role in the differentiation of primary keratinocytes

This work was supported by a project grant from the Biotechnology and Biological Sciences Research Council, UKBreast Tumor Kinase (Brk/PTK6) has a relatively limited expression profile in normal tissue. Its expression is restricted to epithelial cells that are differentiating such as those in the epidermis, and Brk expression appears to be absent from proliferating cells in normal tissue. Also, there is now some evidence to suggest that Brk plays a functional role in the differentiation of the keratinocytes in the epidermis. We have, therefore, investigated the role that Brk/PTK6 plays in normal human primary keratinocytes by suppressing protein levels using RNA interference. We show that as primary human keratinocytes are induced to differentiate in vitro, Brk levels decrease. Decreasing Brk protein levels lead to an increase in the number of cells with a permeable plasma membrane, a decrease in epidermal growth factor receptor (EGFR) and a parallel increase in keratin 10 levels, but classical markers of apoptosis or terminal differentiation are not affected. We propose Brk, Keratin 10 and EGFR are co-regulated during differentiation and that manipulating Brk expression can influence the differentiation of normal primary human keratinocytes.This article is available through the Brunel University Open Access Publishing Fund

Effects of chlorpyrifos and chlorpyrifos-methyl on the outgrowth of axon-like processes, tubulin, and GAP-43 in N2a cells

The aim of this work was to study the neurodegenerative effects of the organophosphate (OP) pesticides chlorpyrifos (CPF) and chlorpyrifos-methyl (CHM) on cultured mouse N2a neuroblastoma cells. CPF or CHM, at a subcytotoxic concentration of 3 μM, were added to the cells either at the time of the induction of cell differentiation (codifferentiation) or 16 h after the induction of differentiation (postdifferentiation). CPF and CHM were similar in inhibiting significantly the outgrowth of axon-like processes from N2a cells after only 4 h exposure under both co- and postdifferentiation exposure conditions. Densitometric scanning of Western blots of extracts of cells treated with CPF or CHM for 4 h revealed significantly decreased cross-reactivity with a monoclonal antibody recognizing the protein GAP-43 under post- but not under codifferentiation exposure conditions. Exposure to CPF or CHM for 4 h under postdifferentiation conditions also resulted in reduced fluorescence of N2a cell body staining with anti-GAP-43. Cross-reactivity of Western blots with a monoclonal antibody recognizing -tubulin was not significantly affected by OP treatment. These data indicate that a disturbance in GAP-43 may be important in the retraction of axons in predifferentiated N2a cells and support the notion that the mechanisms involved in CPF-and CHM-induced inhibition of axonal outgrowth may be different under co- and postdifferentiation exposure conditions

The Cone Dysfunction Syndromes

The cone dysfunction syndromes are a heterogeneous group of inherited, predominantly stationary retinal disorders characterised by reduced central vision, and varying degrees of colour vision abnormalities, nystagmus and photophobia. This review details the following conditions: complete and incomplete achromatopsia, blue-cone monochromatism, oligocone trichromacy, bradyopsia, and Bornholm eye disease. We describe the clinical, psychophysical, electrophysiological and imaging findings that are characteristic to each condition, in order to aid their accurate diagnosis, as well as highlight some classically held notions about these diseases that have come to be challenged over recent years. The latest data regarding the genetic aetiology and pathological changes observed in the cone dysfunction syndromes are discussed, and, where relevant, translational avenues of research, including completed and anticipated interventional clinical trials, for some of the diseases described herein will be presented. Finally, we briefly review the current management of these disorders

An exploratory investigation examining male and female students' initial impressions and expectancies of lecturers

The aim of this study was to examine the informational cues that male and female students perceive to be influential when developing initial impressions and expectancies of a lecturer. University students (n 752) rated the extent to which 30 informational cues influence their initial perceptions of a lecturer. Following exploratory factor analysis (EFA), a five-factor model (i.e. appearance (APP), accessories (ACC), third-party reports (TPR), communication skills (CS) and nationality/ethnicity (NE)) was extracted for male students and a five-factor model (i.e. ACC, TPR, APP, interpersonal skills (IPS) and engagement (ENG)) extracted for female students. Inspection of mean scores identified that male students rated CS (e.g. clarity of voice) and TPR (e.g. qualifications) and female students IPS (e.g. control of class), ENG (e.g. eye contact) and TPR to be influential factors in forming initial impressions and expectancies of a lecturer. The findings further identify the potential for expectancy effects within student lecturer interactions