156 research outputs found

    Experimental and theoretical investigation of the effect of rotating circular cylinder speed on the lift and drag forces

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    Flow past a circular cylinder is a problem for understanding flow around bluff bodies. This flow has been studied both experimentally and numerically of laminar infinite flow of viscous incompressible fluid around a rotating circular cylinder at Reynolds number 80,120,160 and dimensionless rotation rate, α , (ratio of cylinder surface speed to the free stream velocity) varying from 0 to 6 has been carried out. Navier–Stokes and continuity equations were solved numerically by using finite volume technique is conducted with ANSYS CFX 15 package program. High Speed Photography and LDV, present new experimental results for correlation purposes, captured the flow profile. Rotation can be used as a drag reduction technique. Comparison with previous studies showed good agreement

    Modeling of Pollutants Prediction from Fuel Burning in Oil and Gas Refineries

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    Oxides of nitrogen (NO + NO2 , (NOx)) are emitted from refineries, not only contribute to the production of photochemical smog at ground level but also cause damage to plant life and add to the problem of acid rain. The small amounts of prompt NO produced in the furnace chambers and oil refineries because the formation of NOx can be attributed to four distinct chemical kinetic processes: thermal NOx formation, prompt NOx formation, fuel NOx formation, and intermediate N2O. In this paper, the portions of pollutants that resulted in fuel burning (liquid or gas) in oil and gas refinery were studied by modeling of emitted gases in furnace chamber. The case study at Nassiriya power plant with different loads (70 – 210) MW was studied. The method of finite volume was studied to predict the pollutant portions by using FLUENT computer code (FLUENT is one of largest codes of computer programs which solve thousands of flow and combustion cases. The case study was drawn graphically then imported to solve by FLUENT). These types of pollution species are NOx and SOx as the important air pollutant influenced the human health. The numerical analysis in calculating the pollutants of chamber gave the findings of crude oil emission in combustion is higher than that at using gaseous fuel.So, the methods of decreasing NOx and SOx pollution by water injection and exhaust gas recirculation are used in refinery operation were presente

    Supported online self-management versus care as usual for symptoms of fatigue, pain and urgency/incontinence in adults with inflammatory bowel disease (IBD-BOOST): study protocol for a randomised controlled trial.

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    BACKGROUND: Despite being in clinical remission, many people with inflammatory bowel disease (IBD) live with fatigue, chronic abdominal pain and bowel urgency or incontinence that limit their quality of life. We aim to test the effectiveness of an online self-management programme (BOOST), developed using cognitive behavioural principles and a theoretically informed logic model, and delivered with facilitator support. PRIMARY RESEARCH QUESTION: In people with IBD who report symptoms of fatigue, pain or urgency and express a desire for intervention, does a facilitator-supported tailored (to patient needs) online self-management programme for fatigue, pain and faecal urgency/incontinence improve IBD-related quality of life (measured using the UK-IBDQ) and global rating of symptom relief (0-10 scale) compared with care as usual? METHODS: A pragmatic two-arm, parallel group randomised controlled trial (RCT), of a 12-session facilitator-supported online cognitive behavioural self-management programme versus care as usual to manage symptoms of fatigue, pain and faecal urgency/incontinence in IBD. Patients will be recruited through a previous large-scale survey of unselected people with inflammatory bowel disease. The UK Inflammatory Bowel Disease Questionnaire and global rating of symptom relief at 6 months are the co-primary outcomes, with multiple secondary outcomes measured also at 6 and 12 months post randomisation to assess maintenance. The RCT has an embedded pilot study, health economics evaluation and process evaluation. We will randomise 680 patients, 340 in each group. Demographic characteristics and outcome measures will be presented for both study groups at baseline. The UK-IBDQ and global rating of symptom relief at 6 and 12 months post randomisation will be compared between the study groups. DISCUSSION: The BOOST online self-management programme for people with IBD-related symptoms of fatigue, pain and urgency has been designed to be easily scalable and implemented. If it is shown to improve patients' quality of life, this trial will enable clinicians and patients to make informed management decisions. This is the first trial, to our knowledge, focused on multiple symptoms prioritised by both people with IBD and health professionals. TRIAL REGISTRATION: ISRCTN71618461 . Registered on 9 September 2019

    Kdm3a lysine demethylase is an Hsp90 client required for cytoskeletal rearrangements during spermatogenesis

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    The lysine demethylase Kdm3a (Jhdm2a, Jmjd1a) is required for male fertility, sex determination, and metabolic homeostasis through its nuclear role in chromatin remodeling. Many histone-modifying enzymes have additional nonhistone substrates, as well as nonenzymatic functions, contributing to the full spectrum of events underlying their biological roles. We present two Kdm3a mouse models that exhibit cytoplasmic defects that may account in part for the globozoospermia phenotype reported previously. Electron microscopy revealed abnormal acrosome and manchette and the absence of implantation fossa at the caudal end of the nucleus in mice without Kdm3a demethylase activity, which affected cytoplasmic structures required to elongate the sperm head. We describe an enzymatically active new Kdm3a isoform and show that subcellular distribution, protein levels, and lysine demethylation activity of Kdm3a depended on Hsp90. We show that Kdm3a localizes to cytoplasmic structures of maturing spermatids affected in Kdm3a mutant mice, which in turn display altered fractionation of beta-actin and gamma-tubulin. Kdm3a is therefore a multifunctional Hsp90 client protein that participates directly in the regulation of cytoskeletal components.Publisher PDFPeer reviewe
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