Out of the Box: Diagnosing Concussions With a Smartphone

Two Purdue University students founded brightlamp, LLC, a company designed to produce consumer-ready software for medical diagnostics, which is currently focused on immediate concussion detection

Environmental controls on benthic food web functions and carbon resource use in subarctic lakes

Climate warming and consequent greening of subarctic landscapes increase the availability of organic carbon to the detrital food webs in aquatic ecosystems. This may cause important shifts in ecosystem functioning through the functional feeding patterns of benthic organisms that rely differently on climatically altered carbon resources. Twenty-five subarctic lakes in Finnish Lapland across a tree line ecotone were analysed for limnological and optical variables, carbon (delta C-13) and nitrogen (delta N-15) stable isotope (SI) composition of surface sediment organic matter (OM) and fossil Chironomidae (Diptera) remains to examine environmental controls behind chironomid functional feeding group (FFG) structure and their isotopic associations for assessing ecosystem functioning and carbon utilisation. We hypothesise that the chironomid SI signatures reflect increased allochthony with increasing allochthonous input, but the resource use may be altered by the functional characteristics of the assemblage. Multivariate analyses indicated that carbon geochemistry in the sediments (delta C-13, delta N-15, C/N), nutrients, indices of productivity (chlorophyll-a) and lake water optical properties, related to increasing presence of OM, played a key role in defining the chironomid FFG composition and isotopic signatures. Response modelling was used to examine how individual FFGs respond to environmental gradients. They showed divergent responses for OM quantity, dissolved organic carbon and nutrients between feeding strategies, suggesting that detritivores and filter feeders prefer contrasting carbon and nutrient conditions, and may thus hold paleoecological indicator potential to identify changes between different carbon fluxes. Benthic production was the primary carbon source for the chironomid assemblages according to a three-source SI mixing model, whereas pelagic and terrestrial components contributed less. Between-lake variability in source utilisation was high and controlled primarily by allochthonous OM inputs. Combination of biogeochemical modelling and functional classification is useful to widen our understanding of subarctic lake ecosystem functions and responses to climate-driven changes in limnology and catchment characteristics for long-term environmental change assessments and functional paleoecology.Peer reviewe

Youth social behaviour and network therapy (Y-SBNT) : adaptation of a family and social network intervention for young people who misuse alcohol and drugs – a randomised controlled feasibility trial

Background: Family interventions appear to be effective at treating young people’s substance misuse. However, implementation of family approaches in UK services is low. This study aimed to demonstrate the feasibility of recruiting young people to an intervention based on an adaptation of adult social behaviour and network therapy. It also sought to involve young people with experience of using substance misuse services in the research process. Objectives: To demonstrate the feasibility of recruiting young people to family and social network therapy and to explore ways in which young people with experience of using substance misuse services could be involved in a study of this nature. Design: A pragmatic, two-armed, randomised controlled open feasibility trial. Setting: Two UK-based treatment services for young people with substance use problems, with recruitment taking place from May to November 2014. Participants: Young people aged 12–18 years, newly referred and accepted for structured interventions for drug and/or alcohol problems. Interventions: A remote, web-based computer randomisation system allocated young people to adapted youth social behaviour and network therapy (Y-SBNT) or treatment as usual (TAU). Y-SBNT participants were intended to receive up to six 50-minute sessions over a maximum of 12 weeks. TAU participants continued to receive usual care delivered by their service. Main outcome measures: Feasibility was measured by recruitment rates, retention in treatment and follow-up completion rates. The main clinical outcome was the proportion of days on which the main problem substance was used in the preceding 90-day period as captured by the Timeline Follow-Back interview at 3 and 12 months. Results: In total, 53 young people were randomised (Y-SBNT, n = 26; TAU, n = 27) against a target of 60 (88.3%). Forty-two young people attended at least one treatment session [Y-SBNT 22/26 (84.6%); TAU 20/27 (74.1%)]; follow-up rates were 77.4% at month 3 and 73.6% at month 12. Data for nine young people were missing at both months 3 and 12, so the main clinical outcome analysis was based on 24 young people (92.3%) in the Y-SBNT group and 20 young people (74.1%) in the TAU group. At month 12, the average proportion of days that the main problem substance was used in the preceding 90 days was higher in the Y-SBNT group than in the TAU group (0.54 vs. 0.41; adjusted mean difference 0.13, 95% confidence interval –0.12 to 0.39; p = 0.30). No adverse events were reported. Seventeen young people with experience of substance misuse services were actively involved throughout the study. They informed key elements of the intervention and research process, ensuring that the intervention was acceptable and relevant to our target groups; contributing to the design of key trial documents, ideas for a new model of public involvement and this report. Two parents were also involved. Conclusions: The adapted intervention could be delivered in young people’s services, and qualitative interviews found that Y-SBNT was acceptable to young people, family members and staff. Engagement of family and network members proved difficult within the intervention and research aspects. The study proved the feasibility of this work in routine services but outcome measurement based on narrow substance use variables may be limited and may fail to capture other important changes in wider areas of functioning for young people. Validation of the EuroQol-5 Dimensions for young people aged 12–18 years should be considered and flexible models for involvement of young people in research are required to achieve inclusive representation throughout all aspects of the research process. Although recommendation of a full trial of the Y-SBNT intervention compared with TAU is not supported, this study can inform future intervention development and UK research within routine addiction services. Trial registration: Current Controlled Trials ISRCTN93446265. Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 15. See the NIHR Journals Library website for further project information

Methods for Echocardiographic Biomechanical Measurements

Heart Failure, a life-threatening condition in which the heart does not pump enough oxygenated blood to meet the needs of the body, affects more than 6 million children and adults in America alone. The failure which occurs is characterized as diastolic dysfunction when the ventricles cannot fill sufficiently, or as systolic dysfunction when the ventricles are too weak to pump. Heart failure remains difficult to detect, with one in three patients going undiagnosed during initial hospital visits with acute symptoms, as the heart remodels to compensate for insufficient pumping. Currently the most widely used non-invasive imaging method for assessing heart function is echocardiography. While echocardiography technology has advanced over the past 50 years, many of the image-based measurements performed are unable take advantage of these new capabilities. This work presents the development of several new methods to extract clinically relevant biomechanics measurements from echocardiography and demonstrates how these quantities can provide insight into understanding as well as detecting abnormal heart function. A new framework for echocardiographic particle image velocimetry (echoPIV) for the first time enables the technique to be reliably used on patient data collected during routine examination. A novel method for reconstructing the underlying two-dimensional, two-component blood velocity vector field from Color Doppler echocardiograms provides a fully non-invasive modality for visualizing flow in the heart and enables the quantification of the flow physics robustly. Global deformation of the heart chambers is quantified using a novel framework based on the seldom used logarithm-scaled Fourier correlation kernel. These methods are each presented with a test dataset. These tools are utilized to demonstrate the functional changes of cardiac biomechanics that occur in utero versus ex uterofor healthy children and those with hypoplastic left heart syndrome (HLHS). Quantities characterizing the deformation, shape, and hemodynamics of the left and right ventricle show how the heart adapts to self-sustained breathing in normal individuals and the challenges that arise from this in HLHS patients. Finally, methods of machine learning are employed to train a model to predict patients at high risk of heart failure based on fundamental cardiac function parameters. This tool shows a 30% improvement in correctly determining patients at high risk versus current guidelines and recommendations used widely by clinicians

Colour-Doppler echocardiography flow field velocity reconstruction using a streamfunction–vorticity formulation

We introduce a new method (Doppler Velocity Reconstruction or DoVeR), for reconstructing two-component velocity fields from colour Doppler scans. DoVeR employs the streamfunction-vorticity equation, which satisfies mass conservation while accurately approximating the flow rate of rotation. We validated DoVeR using artificial colour Doppler images generated from computational fluid dynamics models of left ventricle (LV) flow. We compare DoVeR against the conventional intraventricular vector flow mapping (iVFM(1D)) and reformulated iVFM (iVFM(2D)). LV model error analysis showed that DoVeR is more robust to noise and probe placement, with noise RMS errors (nRMSE) between 3.81% and 6.67%, while the iVFM methods delivered 4.16-24.17% for iVFM(1D) and 4.06-400.21% for iVFM(2D). We test the DoVeR and iVFM methods using in vivo mouse LV ultrasound scans. DoVeR yielded more haemodynamically accurate reconstructions, suggesting that it can provide a more reliable approach for robust quantification of cardiac flow