Improving the applicability of radar rainfall estimates for urban pluvial flood modelling and forecasting

This work explores the possibility of improving the applicability of radar rainfall estimates (whose accuracy is generally insufficient) to the verification and operation of urban storm-water drainage models by employing a number of local gauge-based radar rainfall adjustment techniques. The adjustment techniques tested in this work include a simple mean-field bias (MFB) adjustment, as well as a more complex Bayesian radar-raingauge data merging method which aims at better preserving the spatial structure of rainfall fields. In addition, a novel technique (namely, local singularity analysis) is introduced and shown to improve the Bayesian method by better capturing and reproducing storm patterns and peaks. Two urban catchments were used as case studies in this work: the Cranbrook catchment (9 km2) in North-East London, and the Portobello catchment (53 km2) in the East of Edinburgh. In the former, the potential benefits of gauge-based adjusted radar rainfall estimates in an operational context were analysed, whereas in the latter the potential benefits of adjusted estimates for model verification purposes were explored. Different rainfall inputs, including raingauge, original radar and the aforementioned merged estimates were fed into the urban drainage models of the two catchments. The hydraulic outputs were compared against available flow and depth records. On the whole, the tested adjustment techniques proved to improve the applicability of radar rainfall estimates to urban hydrological applications, with the Bayesian-based methods, in particular the singularity sensitive one, providing more realistic and accurate rainfall fields which result in better reproduction of the urban drainage system’s dynamics. Further testing is still necessary in order to better assess the benefits of these adjustment methods, identify their shortcomings and improve them accordingly

Superconductivity in NdFe1-xCoxAsO (0.05 < x < 0.20) and rare-earth magnetic ordering in NdCoAsO

The phase diagram of NdFe1-xCoxAsO for low cobalt substitution consists of a superconducting dome (0.05 < x < 0.20) with a maximum critical temperature of 16.5(2) K for x = 0.12. The x = 1 end member, NdCoAsO, is an itinerant ferromagnet (TC = 85 K) with an ordered moment of 0.30(1) BM at 15 K. Below TN = 9 K, Nd spin-ordering results in the antiferromagnetic coupling of the existing ferromagnetic planes. Rietveld analysis reveals that the electronically important two-fold tetrahedral angle increases from 111.4 to 115.9 deg. in this series. Underdoped samples with x = 0.046(2) and x = 0.065(2) show distortions to the orthorhombic Cmma structure at 72(2) and 64(2) K, respectively. The temperature dependences of the critical fields Hc2(T) near Tc are linear with almost identical slopes of 2.3(1) T K-1 for x = 0.065(2), x = 0.118(2) and x = 0.172(2). The estimated critical field Hc2(0) and correlation length for optimally doped samples are 26(1) T and 36(1) Angstrom. A comparison of the maximum reported critical temperatures of well-characterized cobalt doped 122- and 1111-type superconductors is presented.Comment: accepted to PR

Kv2 dysfunction after peripheral axotomy enhances sensory neuron responsiveness to sustained input

AbstractPeripheral nerve injuries caused by trauma are associated with increased sensory neuron excitability and debilitating chronic pain symptoms. Axotomy-induced alterations in the function of ion channels are thought to largely underlie the pathophysiology of these phenotypes. Here, we characterise the mRNA distribution of Kv2 family members in rat dorsal root ganglia (DRG) and describe a link between Kv2 function and modulation of sensory neuron excitability. Kv2.1 and Kv2.2 were amply expressed in cells of all sizes, being particularly abundant in medium-large neurons also immunoreactive for neurofilament-200. Peripheral axotomy led to a rapid, robust and long-lasting transcriptional Kv2 downregulation in the DRG, correlated with the onset of mechanical and thermal hypersensitivity. The consequences of Kv2 loss-of-function were subsequently investigated in myelinated neurons using intracellular recordings on ex vivo DRG preparations. In naïve neurons, pharmacological Kv2.1/Kv2.2 inhibition by stromatoxin-1 (ScTx) resulted in shortening of action potential (AP) after-hyperpolarization (AHP). In contrast, ScTx application on axotomized neurons did not alter AHP duration, consistent with the injury-induced Kv2 downregulation. In accordance with a shortened AHP, ScTx treatment also reduced the refractory period and improved AP conduction to the cell soma during high frequency stimulation. These results suggest that Kv2 downregulation following traumatic nerve lesion facilitates greater fidelity of repetitive firing during prolonged input and thus normal Kv2 function is postulated to limit neuronal excitability. In summary, we have profiled Kv2 expression in sensory neurons and provide evidence for the contribution of Kv2 dysfunction in the generation of hyperexcitable phenotypes encountered in chronic pain states

Seasonal variability of the warm Atlantic Water layer in the vicinity of the Greenland shelf break

The warmest water reaching the east and west coast of Greenland is found between 200?m and 600?m. Whilst important for melting Greenland's outlet glaciers, limited winter observations of this layer prohibit determination of its seasonality. To address this, temperature data from Argo profiling floats, a range of sources within the World Ocean Database and unprecedented coverage from marine-mammal borne sensors have been analysed for the period 2002-2011. A significant seasonal range in temperature (~1-2?°C) is found in the warm layer, in contrast to most of the surrounding ocean. The phase of the seasonal cycle exhibits considerable spatial variability, with the warmest water found near the eastern and southwestern shelf-break towards the end of the calendar year. High-resolution ocean model trajectory analysis suggest the timing of the arrival of the year's warmest water is a function of advection time from the subduction site in the Irminger Basin

Feasibility of metabolic imaging of hyperpolarized 13C-pyruvate in human breast cancer

Introduction Imaging of the breast with hyperpolarized 13C yields new challenges compared to imaging the prostate [1]. E.g. large anteroposterior B0 gradients [2] require correction and the anatomy and patient positioning need a new, highly optimized RF coil array for achieving sufficient SNR/spatial resolution. As a first step, we have investigated single-breast imaging in the coronal plane. Methods A BRCA gene carrier with a 38-mm diameter grade 3 triple-negative invasive ductal carcinoma was studied on a 3T MRI (GE Healthcare) using a prototype 8-channel 13C breast coil (Rapid Biomedical), containing 2 transmit/receive coils and 6 receive-only covering both breasts in a prone position. 1H imaging was performed with the body coil. Following injection of 40ml of 250mM 13C-pyruvate, polarized to c. 25%, a 1-minute time series of spirals with IDEAL encoding (3) was collected (flip angle 10°, TR=260ms, 8-step cycle, time resolution 2.08s, 3 x 3-cm thick slices, 3mm gap, 40-pt spiral, 24cm coronal FOV, real pixel size 12 x 12 x 30mm). IDEAL reconstruction of images was optimized separately for each slice to enable independent frequency offsets to be applied. Kinetic modelling was performed in MATLAB, with automated tumour segmentation. Results Tumour pixels were identified by the segmentation algorithm only in the tumour-containing slice 2, and the average estimated flux from pyruvate to lactate kPL within this ROI was 0.022 s-1 (Fig. 1). The frequency shift of pyruvate relative to slice 2 was +6 Hz in slice 3 and -34 Hz in slice 1, confirming a sharp gradient in B0 approaching the nipple, which was corrected by optimizing slices separately (Fig 2). Images of lactate and pyruvate summed over the time course (Fig 3) showed strong signal of both metabolites over the tumour in slice 2, lower pyruvate in the slice toward the chest wall, and no consistent signal in slice 1. Conclusion This first-in-Europe study in breast cancer established the feasibility of obtaining metabolite images with high temporal and moderate spatial resolution in humans in vivo following administration of hyperpolarized 13C-pyruvate. Coronal image orientation allowed application of significant corrections for a known limitation, the anteroposterior B0 gradient, as well as a small FOV to improve spatial resolution. Kinetic rate constants within the tumour were found to be consistent with previous reports in human prostate cancer (1). References 1) Nelson SJ et al. Sci Transl Med 5, 198ra108 (2013). 2) Maril N, et al. Magn. Reson. Med. 2005; 54:1139-1145. 3) Wiesinger F, et al. Magn Reson Med 2012; 68:8-16

Epidemic space

The aim of this article is to highlight the importance of 'spatiality' in understanding the materialization of risk society and cultivation of risk sensibilities. More specifically it provides a cultural analysis of pathogen virulence (as a social phenomenon) by means of tracing and mapping the spatial flows that operate in the uncharted zones between the microphysics of infection and the macrophysics of epidemics. It will be argued that epidemic space consists of three types of forces: the vector, the index and the vortex. It will draw on Latour's Actor Network Theory to argue that epidemic space is geared towards instability when the vortex (of expanding associations and concerns) displaces the index (of finding a single cause)

CONservative TReatment of Appendicitis in Children – a randomised controlled feasibility Trial (CONTRACT)

Objective To establish the feasibility of a multicentre randomised controlled trial to assess the effectiveness and cost-effectiveness of a non-operative treatment pathway compared with appendicectomy in children with uncomplicated acute appendicitis.Design Feasibility randomised controlled trial with embedded qualitative study to inform recruiter training to optimise recruitment and the design of a future definitive trial.Setting Three specialist paediatric surgery centres in the UK.Patients Children (aged 4–15 years) with a clinical diagnosis of uncomplicated acute appendicitis.Interventions Appendicectomy or a non-operative treatment pathway (comprising broad-spectrum antibiotics and active observation).Main outcome measures Primary outcome measure was the proportion of eligible patients recruited. Secondary outcomes evaluated adherence to interventions, data collection during follow-up, safety of treatment pathways and clinical course.Results Fifty per cent of eligible participants (95% CI 40 to 59) approached about the trial agreed to participate and were randomised. Repeated bespoke recruiter training was associated with an increase in recruitment rate over the course of the trial from 38% to 72%. There was high acceptance of randomisation, good patient and surgeon adherence to trial procedures and satisfactory completion of follow-up. Although more participants had perforated appendicitis than had been anticipated, treatment pathways were found to be safe and adverse event profiles acceptable.Conclusion Recruitment to a randomised controlled trial examining the effectiveness and cost-effectiveness of a non-operative treatment pathway compared with appendicectomy for the treatment of uncomplicated acute appendicitis in children is feasible.Trial registration number ISRCTN15830435

Copy number architectures define treatment-mediated selection of lethal prostate cancer clones

Despite initial responses to hormone treatment, metastatic prostate cancer invariably evolves to a lethal state. To characterize the intra-patient evolutionary relationships of metastases that evade treatment, we perform genome-wide copy number profiling and bespoke approaches targeting the androgen receptor (AR) on 167 metastatic regions from 11 organs harvested post-mortem from 10 men who died from prostate cancer. We identify diverse and patient-unique alterations clustering around the AR in metastases from every patient with evidence of independent acquisition of related genomic changes within an individual and, in some patients, the co-existence of AR-neutral clones. Using the genomic boundaries of pan-autosome copy number changes, we confirm a common clone of origin across metastases and diagnostic biopsies, and identified in individual patients, clusters of metastases occupied by dominant clones with diverged autosomal copy number alterations. These autosome-defined clusters are characterized by cluster-specific AR gene architectures, and in two index cases are topologically more congruent than by chance (p-values 3.07 × 10-8 and 6.4 × 10-4). Integration with anatomical sites suggests patterns of spread and points of genomic divergence. Here, we show that copy number boundaries identify treatment-selected clones with putatively distinct lethal trajectories

Conservative treatment for uncomplicated appendicitis in children:the CONTRACT feasibility study, including feasibility RCT

Background Whilst non-operative treatment is known to be effective for the treatment of uncomplicated acute appendicitis in children, comparative randomised trial data reporting important outcomes compared to appendicectomy are lacking.ObjectivesTo ascertain the feasibility of conducting a multi-centre randomised controlled trial (RCT) testing the effectiveness and cost-effectiveness of a non-operative treatment pathway compared to appendicectomy for the treatment of uncomplicated acute appendicitis in children.•DesignMixed methods study including: a feasibility RCT; embedded and parallel qualitative and survey studies; parallel health economic feasibility study; development of a core outcome set.Setting Three specialist NHS Paediatric Surgical Units in EnglandParticipants Children (aged 4-15 years) clinically diagnosed with uncomplicated acute appendicitis participated in the feasibility RCT. Children, their families, recruiting clinicians and other healthcare professionals involved in caring for children with appendicitis took part in the qualitative study. UK Specialist Paediatric Surgeons took part in the survey. Specialist Paediatric Surgeons, Adult General Surgeons who treat children, and children and young people who previously had appendicitis along with their families took part in the core outcomes set development.Interventions Participants in the feasibility RCT were randomised to a non-operative treatment pathway (broad-spectrum antibiotics and active observation) or appendicectomy.Main outcome measures Primary outcome measure was the proportion of eligible patients recruited to the feasibility trial.Data sourcesNHS casenotes, questionnaire responses, transcribed audio recordings of recruitment discussions and qualitative interviewsResults Overall, 50% (95%CI 40-59) of 115 eligible participants approached about the trial agreed to participate and were randomised. There was high acceptance of randomisation and good adherence to trial procedures and follow-up (follow rates of 89%, 85% and 85% at six weeks, three months and six months respectively). More participants had perforated appendicitis than had been anticipated.Qualitative work enabled us to: communicate about the trial effectively with patients and families; design and deliver bespoke training to optimise recruitment; and understand how to optimise design and delivery of a future trial.The health economic study, indicated that the main cost drivers are the ward stay cost and the cost of the operation, and has informed quality of life assessment methods for future work.A core outcome set for the treatment of uncomplicated acute appendicitis in children and young people was developed, containing 14 outcomes.There is adequate surgeon interest to justify proceeding to an effectiveness trial with 51% of those surveyed expressing a willingness to recruit with an unchanged trial protocol.LimitationsSince the feasibility RCT was only performed in three centres we cannot guarantee successful recruitment across a larger number of sites. However, our qualitative work has informed a bespoke training package to facilitate this. Although survey results suggest adequate clinician interest to make a larger trial possible, actual participation may differ, and equipoise may have moved over time.Conclusions A future effectiveness trial is feasible following limited additional preparation to establish appropriate outcome measures and case identification. We recommend a limited package of qualitative work be included to optimise recruitment at new centres in particular.Future work Prior to proceeding to an effectiveness trial we need to: develop a robust method for distinguishing children with uncomplicated acute appendicitis from those with more advanced appendicitis; reach agreement on a primary outcome measure and effect size that is acceptable to all stakeholder groups involved.Study registration ISRCTN15830435.Funding detailsNIHR HTA programm