401 research outputs found
Application of electron beam technology in improving sewage water quality: An advance technique
The use of electron beam to disinfect sewage water is gaining importance. The current problem on environmental health in relation to water pollution insists for the safe disposal of sewage water. In general, sewage water comprises of heterogeneous organic based chemicals as well as pathogens. EB (electron beam) treatment of the wastewater was found to be very effective in reducing the pathogens as well as organic load. EB dose of 1.5 kGy was sufficient for complete elimination of total coli forms. The experimental results elucidated that the reduction of biological oxygen demand (BOD) (30.38 and 51.7%) in both inlet and outlet sewage samples. Similarly, reduction of chemical oxygen demand (COD) was observed (37.54 and 52.32%) both sewage samples with respect to increasing of irradiation doses (0.45 to 6 kGy). The present study demonstrated the potential of ionizing radiation for disinfection of sewage and to increase the water quality of the wastewater by decreasing BOD and COD. So, the irradiation sewage water can find its application either in agriculture for irrigation or in industry sector for cooling purpose or in both the sectors.Key words: Disinfection, electron beam accelerator, organic matter, sewage water quality
Mapping the rotational diffusion of fluorophores in cells with time-resolved wide-field fluorescence anisotropy imaging
CLEO/EUROPE ; EQEC European Quantum Electronics Conference, Munich ICM, Germany, 22-27 June, 2003N
Real-world performance and accuracy of stress echocardiography: The EVAREST observational multi-centre study
Aims - Stress echocardiography is widely used to identify obstructive coronary artery disease. High accuracy is reported in expert hands but is dependent on operator training and image quality. The EVAREST study provides UK-wide data to evaluate real-world performance and accuracy of stress echocardiography.
Methods and Results - Participants undergoing stress echocardiography for coronary artery disease were recruited from 31 hospitals. Participants were followed up through health records which underwent expert adjudication. Cardiac outcome was defined as anatomically or functionally-significant stenosis on angiography, revascularisation, medical management of ischaemia, acute coronary syndrome or cardiac-related death within six months. 5131 patients (55% male) participated with a median age of 65 years (IQR 57 – 74). 72.9% of studies used dobutamine and 68.5% were contrast studies. Inducible ischaemia was present in 19.3% of scans. Sensitivity and specificity for prediction of a cardiac outcome were 95.4% and 96.0%, respectively, with an accuracy of 95.9%. Sub-group analysis revealed high levels of predictive accuracy across a wide range of patient and protocol sub-groups, with the presence of a resting regional wall motion abnormalitiy significantly reducing the performance of both dobutamine (p<0.01) and exercise (p<0.05) stress echocardiography (p<0.05). Overall accuracy remained consistently high across all participating hospitals.
Conclusion – Stress echocardiography has high accuracy across UK-based hospitals and thus indicates stress echocardiography is being delivered effectively in real-world practice, reinforcing its role as a first-line investigation in the assessment of patients with stable chest pain
Numerical loop quantum cosmology: an overview
A brief review of various numerical techniques used in loop quantum cosmology
and results is presented. These include the way extensive numerical simulations
shed insights on the resolution of classical singularities, resulting in the
key prediction of the bounce at the Planck scale in different models, and the
numerical methods used to analyze the properties of the quantum difference
operator and the von Neumann stability issues. Using the quantization of a
massless scalar field in an isotropic spacetime as a template, an attempt is
made to highlight the complementarity of different methods to gain
understanding of the new physics emerging from the quantum theory. Open
directions which need to be explored with more refined numerical methods are
discussed.Comment: 33 Pages, 4 figures. Invited contribution to appear in Classical and
Quantum Gravity special issue on Non-Astrophysical Numerical Relativit
Development of a risk score for early saphenous vein graft failure: An individual patient data meta-analysis
Objectives: Early saphenous vein graft (SVG) occlusion is typically attributed to technical factors. We aimed at exploring clinical, anatomical, and operative factors associated with the risk of early SVG occlusion (within 12 months postsurgery). Methods: Published literature in MEDLINE was searched for studies reporting the incidence of early SVG occlusion. Individual patient data (IPD) on early SVG occlusion were used from the SAFINOUS-CABG Consortium. A derivation (n = 1492 patients) and validation (n = 372 patients) cohort were used for model training (with 10-fold cross-validation) and external validation respectively. Results: In aggregate data meta-analysis (48 studies, 41,530 SVGs) the pooled estimate for early SVG occlusion was 11%. The developed IPD model for early SVG occlusion, which included clinical, anatomical, and operative characteristics (age, sex, dyslipidemia, diabetes mellitus, smoking, serum creatinine, endoscopic vein harvesting, use of complex grafts, grafted target vessel, and number of SVGs), had good performance in the derivation (c-index = 0.744; 95% confidence interval [CI], 0.701-0.774) and validation cohort (c-index = 0.734; 95% CI, 0.659-0.809). Based on this model. we constructed a simplified 12-variable risk score system (SAFINOUS score) with good performance for early SVG occlusion (c-index = 0.700, 95% CI, 0.684-0.716). Conclusions: From a large international IPD collaboration, we developed a novel risk score to assess the individualized risk for early SVG occlusion. The SAFINOUS risk score could be used to identify patients that are more likely to benefit from aggressive treatment strategies
Structural analysis of underivatized neutral human milk oligosaccharides in the negative ion mode by nano-electrospray MSn (Part 2: Application to isomeric mixtures)
Fermions in Loop Quantum Cosmology and the Role of Parity
Fermions play a special role in homogeneous models of quantum cosmology
because the exclusion principle prevents them from forming sizable matter
contributions. They can thus describe the matter ingredients only truly
microscopically and it is not possible to avoid strong quantum regimes by
positing a large matter content. Moreover, possible parity violating effects
are important especially in loop quantum cosmology whose basic object is a
difference equation for the wave function of the universe defined on a discrete
space of triads. The two orientations of a triad are interchanged by a parity
transformation, which leaves the difference equation invariant for ordinary
matter. Here, we revisit and extend loop quantum cosmology by introducing
fermions and the gravitational torsion they imply, which renders the parity
issue non-trivial. A treatable locally rotationally symmetric Bianchi model is
introduced which clearly shows the role of parity. General wave functions
cannot be parity-even or odd, and parity violating effects in matter influence
the microscopic big bang transition which replaces the classical singularity in
loop quantum cosmology.Comment: 17 page
Development and characterization of a microfluidic model of the tumour microenvironment
The physical microenvironment of tumours is characterized by heterotypic cell interactions and physiological gradients of nutrients, waste products and oxygen. This tumour microenvironment has a major impact on the biology of cancer cells and their response to chemotherapeutic agents. Despite this, most in vitro cancer research still relies primarily on cells grown in 2D and in isolation in nutrient- and oxygen-rich conditions. Here, a microfluidic device is presented that is easy to use and enables modelling and study of the tumour microenvironment in real-time. The versatility of this microfluidic platform allows for different aspects of the microenvironment to be monitored and dissected. This is exemplified here by real-time profiling of oxygen and glucose concentrations inside the device as well as effects on cell proliferation and growth, ROS generation and apoptosis. Heterotypic cell interactions were also studied. The device provides a live ‘window’ into the microenvironment and could be used to study cancer cells for which it is difficult to generate tumour spheroids. Another major application of the device is the study of effects of the microenvironment on cellular drug responses. Some data is presented for this indicating the device’s potential to enable more physiological in vitro drug screening
Energy-efficient precoding in multicell networks with full-duplex base stations
© 2017, The Author(s). This paper considers multi-input multi-output (MIMO) multicell networks, where the base stations (BSs) are full-duplex transceivers, while uplink and downlink users are equipped with multiple antennas and operate in a half-duplex mode. The problem of interest is to design linear precoders for BSs and users to optimize the network’s energy efficiency. Given that the energy efficiency objective is not a ratio of concave and convex functions, the commonly used Dinkelbach-type algorithms are not applicable. We develop a low-complexity path-following algorithm that only invokes one simple convex quadratic program at each iteration, which converges at least to the local optimum. Numerical results demonstrate the performance advantage of our proposed algorithm in terms of energy efficiency
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