First year student experience

The application was made on behalf of the undergraduate courses team who sought to enhance the first year experience by engaging students in the practice of business. The intention was to develop and signpost enterprising qualities and characteristics in first year learners and develop confidence as well as competence. The undergraduate review for FBL commenced in September 2009. This offered an opportunity to innovate and build good practice in enterprise learning as a pilot to inform the undergraduate review. The team sought to provide a coherent and relevant set of learning experiences that could be achieved outside structured curriculum that would enable learning through live projects

EVALUATING A STUDENT CENTRED APPROACH TO TEACHING AND LEARNING ON A POST-GRADUATE PROFESSIONAL MODULE

The paper explores the impact of embedding a student centred approach to teaching and learning on a post-graduate professional module with a mixed cohort in terms of previous academic experience and cultural background. It was the first module on the programme and student performance was assessed by summative examination. The student-centred approach was characterised by interactive discussion based delivery, group work and formative assessment and feedback on a weekly basis. In addition students were invited to undertake a mock exam as independent study and formative audio feedback was provided. Student views on the process were surveyed and responses were highly positive. As assessment data suggests that students who engage with the formative process do better at summative assessment, the next step for the tutors will be to explore ways of engaging the students who do not currently participate

Dietary aflatoxin exposure and impaired growth in young children from Benin and Togo: cross sectional study

Fetal and early childhood environment, including the nutritional status of the pregnant mother and the infant, are considered critical for growth and risk of disease in later life. Many people in developing coun­ tries are not only malnourished but also chronically exposed to high levels of toxic fungal metabolites (mycotoxins). One family of mycotoxins, the aflatoxins, are carcinogenic and immunotoxic and cause growth retardation in animals. Aflatoxins contaminate staple foods in West Africa, particularly maize and ground­ nuts, as a result of hot, humid storage conditions that promote fungal growth. High exposure to aflatoxins occurs throughout childhood in the region, suggest­ ing that growth and development could be critically affected.We assessed exposure to aflatoxins in relation to anthropometric measures in children in Benin and Togo

Probabilistic Model Counting with Short XORs

The idea of counting the number of satisfying truth assignments (models) of a formula by adding random parity constraints can be traced back to the seminal work of Valiant and Vazirani, showing that NP is as easy as detecting unique solutions. While theoretically sound, the random parity constraints in that construction have the following drawback: each constraint, on average, involves half of all variables. As a result, the branching factor associated with searching for models that also satisfy the parity constraints quickly gets out of hand. In this work we prove that one can work with much shorter parity constraints and still get rigorous mathematical guarantees, especially when the number of models is large so that many constraints need to be added. Our work is based on the realization that the essential feature for random systems of parity constraints to be useful in probabilistic model counting is that the geometry of their set of solutions resembles an error-correcting code.Comment: To appear in SAT 1

Similar biodiversity of ectomycorrhizal fungi in set-aside plantations and ancient old-growth broadleaved forests

Setting aside overmature planted forests is currently seen as an option for preserving species associated with old-growth forests, such as those with dispersal limitation. Few data exist, however, on the utility of set-aside plantations for this purpose, or the value of this habitat type for biodiversity relative to old-growth semi-natural ecosystems. Here, we evaluate the contribution of forest type relative to habitat characteristics in determining species richness and composition in seven forest blocks, each containing an ancient old-growth stand (> 1000 yrs) paired with a set-aside even-aged planted stand (ca. 180 yrs). We investigated the functionally important yet relatively neglected ectomycorrhizal fungi (EMF), a group for which the importance of forest age has not been assessed in broadleaved forests. We found that forest type was not an important determinant of EMF species richness or composition, demonstrating that set-aside can be an effective option for conserving ancient EMF communities. Species richness of above-ground EMF fruiting bodies was principally related to the basal area of the stand (a correlate of canopy cover) and tree species diversity, whilst richness of below-ground ectomycorrhizae was driven only by tree diversity. Our results suggest that overmature planted forest stands, particularly those that are mixed-woods with high basal area, are an effective means to connect and expand ecological networks of ancient old-growth forests in historically deforested and fragmented landscapes for ectomycorrhizal fungi

Fungal infections in liver transplant recipients

Sixty-two adults who underwent orthotopic liver transplantations between February 1981 and June 1983 were followed for a mean of 170 days after the operation. Twenty-six patients developed 30 episodes of significant fungal infection. Candida species and Torulopsis glabrata were responsible for 22 episodes and Aspergillus species for 6. Most fungal infections occurred in the first month after transplantation. In the first 8 weeks after transplantation, death occurred in 69% (18/26) of patients with fungal infection but in only 8% (3/36) of patients without fungal infection (P<0.0005). The cause of death, however, was usually multifactorial, and not solely due to the fungal infection. Fungal infections were associated with the following clinical factors: administration of preoperative steroids (P<0.05) and antibiotics (P<0.05), longer transplant operative time (P<0.02), longer posttransplant operative time (P<0.01), duration of antibiotic use after transplant surgery (P<0.001), and the number of steroid boluses administered to control rejection in the first 2 posttransplant months (P<0.01). Patients with primary biliary cirrhosis had fewer fungal infections than patients with other underlying liver diseases (P<0.05). A total of 41% (9/22) of Candida infections resolved, but all Aspergillus infections ended in death. © 1985 by The Williams & Wilkins Co

Early time dynamics of laser-ablated silicon using ultrafast grazing incidence X-ray scattering

Controlling the morphology of laser-derived nanomaterials is dependent on developing a better understanding of the particle nucleation dynamics in the ablation plume. Here, we utilize the femtosecond-length pulses from an x-ray free electron laser to perform time-resolved grazing incidence x-ray scattering measurements on a laser-produced silicon plasma plume. At 20 ps we observe a dramatic increase in the scattering amplitude at small scattering vectors, which we attribute to incipient formation of liquid silicon droplets. These results demonstrate the utility of XFELs as a tool for characterizing the formation dynamics of nanomaterials in laser-produced plasma plumes on ultrafast timescales

Shear Modes, Criticality and Extremal Black Holes

We consider a (2+1)-dimensional field theory, assumed to be holographically dual to the extremal Reissner-Nordstrom AdS(4) black hole background, and calculate the retarded correlators of charge (vector) current and energy-momentum (tensor) operators at finite momentum and frequency. We show that, similar to what was observed previously for the correlators of scalar and spinor operators, these correlators exhibit emergent scaling behavior at low frequency. We numerically compute the electromagnetic and gravitational quasinormal frequencies (in the shear channel) of the extremal Reissner-Nordstrom AdS(4) black hole corresponding to the spectrum of poles in the retarded correlators. The picture that emerges is quite simple: there is a branch cut along the negative imaginary frequency axis, and a series of isolated poles corresponding to damped excitations. All of these poles are always in the lower half complex frequency plane, indicating stability. We show that this analytic structure can be understood as the proper limit of finite temperature results as T is taken to zero holding the chemical potential fixed.Comment: 28 pages, 7 figures, added reference

Holographic non-relativistic fermionic fixed point and bulk dipole coupling

Inspired by the recently discovered non-relativistic fermionic fixed points, we investigate how the presence of bulk dipole coupling modifies the spectral function at one of these novel fixed points. As a result, although the infinite flat band is always visible in the presence of the bulk dipole coupling as well as chemical potential, the band is modified in a remarkable way at small momenta up to the order of magnitude of bulk dipole coupling. On the other hand, like a phoenix, a new Fermi surface sprouts from the formed gap when the bulk dipole coupling is pushed up further such as to overshadow the charge parameter, which is obviously different from what is found at the relativistic fixed points.Comment: JHEP style, 1+17 pages, 9 figures, 1 table, typos corrected, references added, version to appear in JHE

New Constraints (and Motivations) for Abelian Gauge Bosons in the MeV-TeV Mass Range

We survey the phenomenological constraints on abelian gauge bosons having masses in the MeV to multi-GeV mass range (using precision electroweak measurements, neutrino-electron and neutrino-nucleon scattering, electron and muon anomalous magnetic moments, upsilon decay, beam dump experiments, atomic parity violation, low-energy neutron scattering and primordial nucleosynthesis). We compute their implications for the three parameters that in general describe the low-energy properties of such bosons: their mass and their two possible types of dimensionless couplings (direct couplings to ordinary fermions and kinetic mixing with Standard Model hypercharge). We argue that gauge bosons with very small couplings to ordinary fermions in this mass range are natural in string compactifications and are likely to be generic in theories for which the gravity scale is systematically smaller than the Planck mass - such as in extra-dimensional models - because of the necessity to suppress proton decay. Furthermore, because its couplings are weak, in the low-energy theory relevant to experiments at and below TeV scales the charge gauged by the new boson can appear to be broken, both by classical effects and by anomalies. In particular, if the new gauge charge appears to be anomalous, anomaly cancellation does not also require the introduction of new light fermions in the low-energy theory. Furthermore, the charge can appear to be conserved in the low-energy theory, despite the corresponding gauge boson having a mass. Our results reduce to those of other authors in the special cases where there is no kinetic mixing or there is no direct coupling to ordinary fermions, such as for recently proposed dark-matter scenarios.Comment: 49 pages + appendix, 21 figures. This is the final version which appears in JHE