Calibration of colour gradient bias in shear measurement using HST/CANDELS data

Accurate shape measurements are essential to infer cosmological parameters from large area weak gravitational lensing studies. The compact diffraction-limited point-spread function (PSF) in space-based observations is greatly beneficial, but its chromaticity for a broad band observation can lead to new subtle effects that could hitherto be ignored: the PSF of a galaxy is no longer uniquely defined and spatial variations in the colours of galaxies result in biases in the inferred lensing signal. Taking Euclid as a reference, we show that this colourgradient bias (CG bias) can be quantified with high accuracy using available multi-colour Hubble Space Telescope (HST) data. In particular we study how noise in the HST observations might impact such measurements and find this to be negligible. We determine the CG bias using HST observations in the F606W and F814W filters and observe a correlation with the colour, in line with expectations, whereas the dependence with redshift is weak. The biases for individual galaxies are generally well below 1%, which may be reduced further using morphological information from the Euclid data. Our results demonstrate that CG bias should not be ignored, but it is possible to determine its amplitude with sufficient precision, so that it will not significantly bias the weak lensing measurements using Euclid data

The “Eyeballing” technique : an emerging and alerting trend of alcohol misuse

Alternative methods of alcohol consumption have recently emerged among adolescents and young adults, including the alcohol “eyeballing”, which consist in the direct pouring of alcoholic substances on the ocular surface epithelium. In a context of drug and behavioural addictions change, “eyeballing” can be seen as one of the latest and potentially highly risky new trends. We aimed to analyze the existing medical literature as well as online material on this emerging trend of alcohol misusePeer reviewedFinal Published versio

Coordination in gait: Demonstration of a spectral approach

Many important notions in Life Sciences are linked with the idea of cycles, periodicity, fluctuations and transitions. The aim of this paper is to use spectral analysis in a unique way to study and quantify whole body coordination during gait. A participant walked at 3 km/h and ran at 15 km/h on a treadmill for 2 minutes. Position of the approximate center of rotation of the toe, ankle, knee, hip, shoulder, elbow and wrist, and heel, PSIS and head were collected at 100 Hz using CODAmotion analysis system. Fast Fourier Transform was performed on x-coordinate data of the 1) knee marker; 2) 4 markers attached to the free lower limb (toe, ankle, heel and knee); 3) left and right free lower limbs; 4) whole body (all markers). Gait is described by a largely harmonic and resonant oscillator that operates unilateral free limbs at the stride frequency, and axial regions at the step frequency. Running is described by a more harmonic and resonant oscillating structure than walking, with a 3 times higher Q factor and 47% lower Inharmonicity Index. This method is presented as a way to capture global dynamics of our complex multi-segment system, and presents a novel application of spectral analysis to study coordination in multiple oscillators

Lifecycle environmental impact assessment of an overtopping wave energy converter embedded in breakwater systems

Overtopping breakwater systems are among the most promising technologies for exploiting wave energy to generate electricity. They consist in water reservoirs, embedded in piers, placed on top of ramps, higher than sea-level. Pushed by wave energy, seawater fills up the reservoirs and produces electricity by flowing back down through low headhydro turbines. Different overtopping breakwater systems have been tested worldwide in recent years. This study focuses on the Overtopping BReakwater for Energy Conversion (OBREC) system that has been implemented and tested in the harbor of Naples (Italy). The Life Cycle Assessment of a single replicable module of OBREC has been performed for analyzing potential environmental impacts, in terms of Greenhouse Gas Emissions, considering construction, installation, maintenance, and the operational phases. The Carbon Footprint (i.e., mass of CO2eq) to build wave energy converters integrated in breakwater systems has been estimated, more specifically the "environmental investment" (i.e., the share of Carbon Footprint due to the integration of wave energy converter) needed to generate renewable electricity has been assessed. The Carbon Intensity of Electricity (i.e., the ratio between the CO2eq emitted and the electricity produced) has been then assessed in order to demonstrate the profitability and the opportunity to foster innovation in the field of blue energy. Considering the impact for implementing an operational OBREC module (Carbon Footprint = 1.08 t CO2eq; Environmental Investment = 0.48 t CO2eq) and the electricity production (12.6 MWh/year per module), environmental benefits (avoided emissions) would compensate environmental costs (i.e., Carbon Footprint; Environmental Investment) those provided within a range of 25 and 13 months respectively

HEP Applications Evaluation of the EDG Testbed and Middleware

Workpackage 8 of the European Datagrid project was formed in January 2001 with representatives from the four LHC experiments, and with experiment independent people from five of the six main EDG partners. In September 2002 WP8 was strengthened by the addition of effort from BaBar and D0. The original mandate of WP8 was, following the definition of short- and long-term requirements, to port experiment software to the EDG middleware and testbed environment. A major additional activity has been testing the basic functionality and performance of this environment. This paper reviews experiences and evaluations in the areas of job submission, data management, mass storage handling, information systems and monitoring. It also comments on the problems of remote debugging, the portability of code, and scaling problems with increasing numbers of jobs, sites and nodes. Reference is made to the pioneeering work of Atlas and CMS in integrating the use of the EDG Testbed into their data challenges. A forward look is made to essential software developments within EDG and to the necessary cooperation between EDG and LCG for the LCG prototype due in mid 2003.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics Conference (CHEP03), La Jolla, CA, USA, March 2003, 7 pages. PSN THCT00

Disease-relevant proteostasis regulation of cystic fibrosis transmembrane conductance regulator

Mismanaged protein trafficking by the proteostasis network contributes to several conformational diseases, including cystic fibrosis, the most frequent lethal inherited disease in Caucasians. Proteostasis regulators, as cystamine, enable the beneficial action of cystic fibrosis transmembrane conductance regulator (CFTR) potentiators in \u394F508-CFTR airways beyond drug washout. Here we tested the hypothesis that functional CFTR protein can sustain its own plasma membrane (PM) stability. Depletion or inhibition of wild-type CFTR present in bronchial epithelial cells reduced the availability of the small GTPase Rab5 by causing Rab5 sequestration within the detergent-insoluble protein fraction together with its accumulation in aggresomes. CFTR depletion decreased the recruitment of the Rab5 effector early endosome antigen 1 to endosomes, thus reducing the local generation of phosphatidylinositol-3-phosphate. This diverts recycling of surface proteins, including transferrin receptor and CFTR itself. Inhibiting CFTR function also resulted in its ubiquitination and interaction with SQSTM1/p62 at the PM, favoring its disposal. Addition of cystamine prevented the recycling defect of CFTR by enhancing BECN1 expression and reducing SQSTM1 accumulation. Our results unravel an unexpected link between CFTR protein and function, the latter regulating the levels of CFTR surface expression in a positive feed-forward loop, and highlight CFTR as a pivot of proteostasis in bronchial epithelial cells

Attractor dynamics of elite performance: the high bar longswing

Combining biomechanics and motor control, the aim of this study was to investigate the limit cycle dynamics during the high bar longswing across the UK elite gymnastics pathway age groupings. Senior, junior and development gymnasts (N = 30) performed three sets of eight consecutive longswings on the high bar. The centre of mass motion was examined through Poincaré plots and recurrence quantification analysis exploring the limit cycle dynamics of the longswing. Close to one-dimensional limit cycles were displayed for the senior (correlation dimension (CD) = 1.17 ± .08), junior (CD = 1.26 ± .08) and development gymnasts (CD = 1.33 ± .14). Senior elite gymnasts displayed increased recurrence characteristics in addition to longer longswing duration (p < .01) and lower radial angular velocity of the mass centre (p < .01). All groups of gymnasts had highly recurrent and predictable limit cycle characteristics. The findings of this research support the postulation that the further practice, experience and individual development associated with the senior gymnasts contribute to the refinement of the longswing from a nonlinear dynamics perspective. These findings support the idea of functional task decomposition informing the understanding of skill and influencing coaches’ decisions around skill development and physical preparation

Bidirectional causal control in the dynamics of handstand balance

The aim of this study was to identify motor control solutions associated with the ability to maintain handstand balance. Using a novel approach, we investigated the dynamical interactions between centre of pressure (CoP) and centre of mass (CoM) motion. A gymnastics cohort was divided into a ‘less skilled’ group, who held handstands for 4–6 s, and a ‘more skilled’ group, who held handstands in excess of 10 s. CoP–CoM causality was investigated in anterior–posterior (AP) and medio-lateral (ML) directions, in addition to time–space, time–frequency and Hurst Exponent (H) analyses. Lower AP CoP to CoM causal drive and lower H values (> 0.6) indicated the more skilled gymnasts were less reliant on CoP mechanics to drive CoM motion. More skilled performance demonstrated greater adaptability through use of reactive, as opposed to anticipatory, control strategies. Skilled performers additionally exploited mechanical advantages in ML (e.g. a wider base of support), compared to the less skilled athletes. A multiple regression analysis revealed H and frequency domain measures to be better predictors of handstand balance duration than time–space domain measures. The study findings highlight the advantage of an adaptable motor control system with a directional profile, and provide new insight into the clear, measurable footprint of CoP on the dynamics of CoM