Diversifying assessment across the ‘Two Cultures’: student-produced podcasts in Geography

Since 2008, following growing collective interest in learning technologies and pedagogy, Geography and History departments at Northumbria and Newcastle Universities have successfully incorporated student-generated podcasting into a mixture of science, humanities and social science modules across all undergraduate levels. This paper presents a number of innovative examples using this approach, with the aim of promoting student creativity and analytical skills in ways different from traditional report- or essay-based assessments. It goes on to consider some of the advantages and challenges of this alternative assessment mode, from both student and tutor perspectives, across the science-humanities divide

Non-contact low-frequency ultrasound therapy compared with UK standard of care for venous leg ulcers: a single-centre, assessor-blinded, randomised controlled trial

‘Hard-to-heal’ wounds are those which fail to heal with standard therapy in an orderly and timely manner and may warrant the use of advanced treatments such as non-contact low-frequency ultrasound (NLFU) therapy. This evaluator-blinded, single-site, randomised controlled trial, compared NLFU in addition to UK standard of care [SOC: (NLFU + SOC)] three times a week, with SOC alone at least once a week. Patients with chronic venous leg ulcers were eligible to participate. All 36 randomised patients completed treatment (17 NLFU + SOC, 19 SOC), and baseline demographics were comparable between groups. NLFU + SOC patients showed a −47% (SD: 38%) change in wound area; SOC, −39% (38%) change; and difference, −7·4% [95% confidence intervals (CIs) −33·4–18·6; P = 0·565]. The median number of infections per patient was two in both arms of the study and change in quality of life (QoL) scores was not significant (P = 0·490). NLFU + SOC patients reported a substantial mean (SD) reduction in pain score of −14·4 (14·9) points, SOC patients' pain scores reduced by −5·3 (14·8); the difference was −9·1 (P = 0·078). Results demonstrated the importance of high-quality wound care. Outcome measures favoured NLFU + SOC over SOC, but the differences were not statistically significant. A larger sample size and longer follow-up may reveal NLFU-related improvements not identified in this study

AlGaInN laser diode technology for GHz high-speed visible light communication through plastic optical fiber and water

AlGaInN ridge waveguide laser diodes are fabricated to achieve single-mode operation with optical powers up to 100 mW at ∼420  nm∼420  nm for visible free-space, underwater, and plastic optical fiber communication. We report high-frequency operation of AlGaInN laser diodes with data transmission up to 2.5 GHz for free-space and underwater communication and up to 1.38 GHz through 10 m of plastic optical fiber

Lensed CMB power spectra from all-sky correlation functions

Weak lensing of the CMB changes the unlensed temperature anisotropy and polarization power spectra. Accounting for the lensing effect will be crucial to obtain accurate parameter constraints from sensitive CMB observations. Methods for computing the lensed power spectra using a low-order perturbative expansion are not good enough for percent-level accuracy. Non-perturbative flat-sky methods are more accurate, but curvature effects change the spectra at the 0.3-1% level. We describe a new, accurate and fast, full-sky correlation-function method for computing the lensing effect on CMB power spectra to better than 0.1% at l<2500 (within the approximation that the lensing potential is linear and Gaussian). We also discuss the effect of non-linear evolution of the gravitational potential on the lensed power spectra. Our fast numerical code is publicly available.Comment: 16 pages, 4 figures. Changes to match PRD version including new section on non-linear corrections. CAMB code available at http://camb.info

A simple scheme for allocating capital in a foreign exchange proprietary trading firm

We present a model of capital allocation in a foreign exchange proprietary trading firm. The owner allocates capital to individual traders, who operate within strict risk limits. Traders specialize in individual currencies, but are given discretion over their choice of trading rule. The owner provides the simple formula that determines position sizes – a formula that does not require estimation of the firm-level covariance matrix. We provide supporting empirical evidence of excess risk-adjusted returns to the firm-level portfolio, and we discuss a modification of the model in which the owner dictates the choice of trading rule

Metabolic Abnormalities of Chronic High-Dose Glucocorticoids Are Not Mediated by Hypothalamic AgRP in Male Mice.

Glucocorticoids are potent and widely used medicines but often cause metabolic side effects. A murine model of corticosterone treatment resulted in increased hypothalamic expression of the melanocortin antagonist AgRP in parallel with obesity and hyperglycemia. We investigated how these adverse effects develop over time, with particular emphasis on hypothalamic involvement. Wild-type and Agrp-/- male mice were treated with corticosterone for 3 weeks. Phenotypic, biochemical, protein, and mRNA analyses were undertaken on central and peripheral tissues, including white and brown adipose tissue, liver, and muscle, to determine the metabolic consequences. Corticosterone treatment induced hyperphagia within 1 day in wild-type mice, which persisted for 3 weeks. Despite this early increase in food intake, the body weight only started to increase after 10 days. Hyperinsulinemia occurred at day 1. Also, although after 2 days, alterations were present in the genes often associated with insulin resistance in several peripheral tissues, hyperglycemia only developed at 3 weeks. Throughout, sustained elevation in hypothalamic Agrp expression was present. Mice with Agrp deleted [using clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9, Agrp-/-] were partially protected against corticosterone-induced hyperphagia. However, Agrp-/- mice still had corticosterone-induced increases in body weight and adiposity similar to those of the Agrp+/+ mice. Loss of Agrp did not diminish corticosterone-induced hyperinsulinemia or correct changes in hepatic gluconeogenic genes. Chronic glucocorticoid treatment in mice mimics many of the metabolic side effects seen in patients and leads to a robust increase in Agrp. However, AgRP does not appear to be responsible for most of the glucocorticoid-induced adverse metabolic effects.MR

The intervertebral disc contains intrinsic circadian clocks that are regulated by age and cytokines and linked to degeneration

ObjectivesThe circadian clocks are internal timing mechanisms that drive ∼24-hour rhythms in a tissue-specific manner. Many aspects of the physiology of the intervertebral disc (IVD) show clear diurnal rhythms. However, it is unknown whether IVD tissue contains functional circadian clocks and if so, how their dysregulation is implicated in IVD degeneration.MethodsClock gene dynamics in ex vivo IVD explants (from PER2:: luciferase (LUC) reporter mice) and human disc cells (transduced with lentivirus containingPer2::luc reporters) were monitored in real time by bioluminescence photon counting and imaging. Temporal gene expression changes were studied by RNAseq and quantitative reverse transcription (qRT)-PCR. IVD pathology was evaluated by histology in a mouse model with tissue-specific deletion of the core clock geneBmal1.ResultsHere we show the existence of the circadian rhythm in mouse IVD tissue and human disc cells. This rhythm is dampened with ageing in mice and can be abolished by treatment with interleukin-1β but not tumour necrosis factor α. Time-series RNAseq revealed 607 genes with 24-hour patterns of expression representing several essential pathways in IVD physiology. Mice with conditional knockout ofBmal1in their disc cells demonstrated age-related degeneration of IVDs.ConclusionsWe have established autonomous circadian clocks in mouse and human IVD cells which respond to age and cytokines, and control key pathways involved in the homeostasis of IVDs. Genetic disruption to the mouse IVD molecular clock predisposes to IVD degeneration. These results support the concept that disruptions to circadian rhythms may be a risk factor for degenerative IVD disease and low back pain.</jats:sec

Transcription factor Pit-1 affects transcriptional timing in the dual-promoter human prolactin gene

Gene transcription occurs in short bursts interspersed with silent periods, and these kinetics can be altered by promoter structure. The effect of alternate promoter architecture on transcription bursting is not known. We studied the human prolactin (hPRL) gene that contains two promoters, a pituitary-specific promoter that requires the transcription factor Pit-1, and displays dramatic transcriptional bursting activity, and an alternate upstream promoter that is active in non-pituitary tissues. We studied large hPRL genomic fragments with luciferase reporters, and used bacterial artificial chromosome (BAC) recombineering to manipulate critical promoter regions. Stochastic switch mathematical modelling of single-cell time-lapse luminescence image data revealed that the Pit-1-dependent promoter showed longer, higher-amplitude transcriptional bursts. Knockdown studies confirmed that the presence of Pit-1 stabilised and prolonged periods of active transcription. Pit-1 therefore plays an active role in establishing the timing of transcription cycles, in addition to its cell-specific functions

Recovering 3D clustering information with angular correlations

We study how to recover the full 3D clustering information of P(\vec{k},z), including redshift space distortions (RSD), from 2D tomography using the angular auto and cross spectra of different redshift bins C_\ell(z,z'). We focus on quasilinear scales where the minimum scale \lambda_{min} or corresponding maximum wavenumber k_{max}= 2\pi/\lambda_{min} is targeted to be between k_{max}={0.05-0.2} h/Mpc. For spectroscopic surveys, we find that we can recover the full 3D clustering information when the redshift bin width \Delta z used in the 2D tomography is similar to the targeted minimum scale, i.e. \Delta z ~ {0.6-0.8} \lambda_{min} H(z)/c which corresponds to \Delta z ~ 0.01-0.05 for z<1. This value of \Delta z is optimal in the sense that larger values of \Delta z lose information, while smaller values violate our minimum scale requirement. For a narrow-band photometric survey, with photo-z error \sigma_z=0.004, we find almost identical results to the spectroscopic survey because the photo-z error is smaller than the optimal bin width \sigma_z<\Delta z. For a typical broad-band photometric survey with \sigma_z=0.1, we have that \sigma_z>\Delta z and most radial information is intrinsically lost. The remaining information can be recovered from the 2D tomography if we use \Delta z ~ 2\sigma_z. While 3D and 2D analysis are shown here to be equivalent, the advantage of using angular positions and redshifts is that we do not need a fiducial cosmology to convert to 3D coordinates. This avoids assumptions and marginalization over the fiducial model. In addition, it becomes straight forward to combine RSD, clustering and weak lensing in 2D space.Comment: 13 pages, 6 figures. Minor changes included to match the version accepted for publication in MNRA