105 research outputs found
Musculoskeletal MRI protocol
The authors propose a musculoskeletal (MSK) magnetic resonance imaging (MRI) protocol using selected sequences for common orthopaedic indications. Selected sequences allow optimal visualisation of the indicated pathology while screening for other common conditions. The authors emphasise the need for standard positioning of the patient and standard orientation of scan planes to facilitate comparison with follow-up scans
Analysis of a Metal Matrix Composites Automotive Component
This study presents an implementation of concurrent engineering (CE) and an analytical network process to form a new rating method as part of the manufacturing process and
material analysis in the product development environment. The proposed procedure is referred to as a concurrent network (CN). It is planned for CN to carry out simultaneous
analysis of all aspects of product elements by using CE strategy. Furthermore, CN enables interdependence and interrelationship analysis between product elements by
implementing ANP. In this study, CN is utilized for the manufacturing process and material analysis of a metal matrix composites (MMCs) automotive component which is
the brake disc. The results show that by using CN, all the product parameters can be analyzed comprehensively and the importance weights of the product parameters with regard to the MMCs brake disc performance are obtained. It is concluded that in the manufacturing process cluster the primary process parameter has the highest score, while in the material cluster the ranking is dominated by mechanical properties. This means that these sub-conceptual parameters are the most important ones to consider in order to achieve the required performance of the product
Identification of potential biomarkers in donor cows for in vitro embryo production by granulosa cell transcriptomics
<div><p>The Ovum Pick Up-<i>In vitro</i> Production (OPU-IVP) of embryos is an advanced reproductive technology used in cattle production but the complex biological mechanisms behind IVP outcomes are not fully understood. In this study we sequenced RNA of granulosa cells collected from Holstein cows at oocyte aspiration prior to IVP, to identify candidate genes and biological mechanisms for favourable IVP-related traits in donor cows where IVP was performed separately for each animal. We identified 56 genes significantly associated with IVP scores (BL rate, kinetic and morphology). Among these, <i>BEX2</i>, <i>HEY2</i>, <i>RGN</i>, <i>TNFAIP6</i> and <i>TXNDC11</i> were negatively associated while <i>Mx1</i> and <i>STC1</i> were positively associated with all IVP scores. Functional analysis highlighted a wide range of biological mechanisms including apoptosis, cell development and proliferation and four key upstream regulators (COX2, IL1, PRL, TRIM24) involved in these mechanisms. We found a range of evidence that good IVP outcome is positively correlated with early follicular atresia. Furthermore we showed that high genetic index bulls can be used in breeding without reducing the IVP performances. These findings can contribute to the development of biomarkers from follicular fluid content and to improving Genomic Selection (GS) methods that utilize functional information in cattle breeding, allowing a widespread large scale application of GS-IVP.</p></div
Effect of fibre coating and geometry on the tensile properties of hybrid carbon nanotube coated carbon fibre reinforced composite
Hierarchically structured hybrid composites are ideal engineered materials to carry loads and stresses due to their high in-plane specific mechanical properties. Growing carbon nanotubes (CNTs) on the surface of high performance carbon fibres (CFs) provides a means to tailor the mechanical properties of the fibre-resin interface of a composite. The growth of CNT on CF was conducted via floating catalyst chemical vapor deposition (CVD). The mechanical properties of the resultant fibres, carbon nanotube (CNT) density and alignment morphology were shown to depend on the CNT growth temperature, growth time, carrier gas flow rate, catalyst amount, and atmospheric conditions within the CVD chamber. Carbon nanotube coated carbon fibre reinforced polypropylene (CNT-CF/PP) composites were fabricated and characterized. A combination of Halpin-Tsai equations, Voigt-Reuss model, rule of mixture and Krenchel approach were used in hierarchy to predict the mechanical properties of randomly oriented short fibre reinforced composite. A fractographic analysis was carried out in which the fibre orientation distribution has been analyzed on the composite fracture surfaces with Scanning Electron Microscope (SEM) and image processing software. Finally, the discrepancies between the predicted and experimental values are explained. (C) 2013 Elsevier Ltd. All rights reserved
Effects of two CIDR-based oestrus synchronization protocols on oestrus response in boer goats.
Sixty fertile and healthy female Boer goats were divided equally and randomly into two groups (n=30). The first group received CIDR treatment for 14 days (T14) with 400 IU PMSG and 0.05 mg cloprostenol injection (i.m.) prior to CIDR removal and the second group received CIDR treatment for 9 days (T9) with 0.05 mg cloprostenol injection (i.m.) 24 hours before CIDR removal. The number of does with oestrus and the time of oestrus sign were recorded every 6-hour interval and the observation was conducted from 24 hours after CIDR removal and terminated 66 hours after CIDR removal. Blood samples were taken from all of the does before CIDR insertion and 48 hours after CIDR removal. The results showed all 30 does (100%) in T14 and 28 does (93.3%) in T9 came to oestrus. The mean time of does showing signs of oestrus for both treatments were significantly different in tail flagging and standing to be mounted (P0.05). The current study suggests that CIDR treatment for 14 days with 400 IU PMSG and 0.05 mg cloprostenol prior to CIDR removal gave better result in oestrus synchronisation compared to CIDR treatment for 9 days with 0.05 mg cloprostenol given 24 hours before CIDR removal
Second M-3 muscarinic receptor binding site contributes to bronchoprotection by tiotropium
Background and Purpose The bronchodilator tiotropium binds not only to its main binding site on the M-3 muscarinic receptor but also to an allosteric site. Here, we have investigated the functional relevance of this allosteric binding and the potential contribution of this behaviour to interactions with long-acting beta-adrenoceptor agonists, as combination therapy with anticholinergic agents and beta-adrenoceptor agonists improves lung function in chronic obstructive pulmonary disease. Experimental Approach ACh, tiotropium, and atropine binding to M-3 receptors were modelled using molecular dynamics simulations. Contractions of bovine and human tracheal smooth muscle strips were studied. Key Results Molecular dynamics simulation revealed extracellular vestibule binding of tiotropium, and not atropine, to M-3 receptors as a secondary low affinity binding site, preventing ACh entry into the orthosteric binding pocket. This resulted in a low (allosteric binding) and high (orthosteric binding) functional affinity of tiotropium in protecting against methacholine-induced contractions of airway smooth muscle, which was not observed for atropine and glycopyrrolate. Moreover, antagonism by tiotropium was insurmountable in nature. This behaviour facilitated functional interactions of tiotropium with the beta-agonist olodaterol, which synergistically enhanced bronchoprotective effects of tiotropium. This was not seen for glycopyrrolate and olodaterol or indacaterol but was mimicked by the interaction of tiotropium and forskolin, indicating no direct beta-adrenoceptor-M-3 receptor crosstalk in this effect. Conclusions and Implications We propose that tiotropium has two binding sites at the M-3 receptor that prevent ACh action, which, together with slow dissociation kinetics, may contribute to insurmountable antagonism and enhanced functional interactions with beta-adrenoceptor agonists
Reduced graphene oxide decorated with polypyrrole nanoparticles layer for detection of pyrene using surface plasmon resonance technique
A reduced graphene oxide layer was decorated with polypyrrole nanoparticles (PPy-NPs), and nanocomposite layers were deposited using the electro-chemical technique. The nanocomposite layer was used to detect pyrene using the surface plasmon resonance technique and the results were compared with the polypyrrole layer. The layers were characterized using a field emission scanning electron microscope (FE-SEM), Fourier transfer infrared spectroscopy (FT-IR) and X-Ray diffraction (XRD). Variations in shift of the resonance angle with time were registered to evaluate the sensing layers. It was found that the sensitivity of polypyrrole nanoparticles and reduced graphene oxide nanocomposite layer was higher than that of the polypyrrole layer. The limitation of the nanocomposite sensing layer was about 0.01 ppm which was larger than that of the polypyrrole sensing layer
Comparative health systems research in a context of HIV/AIDS: lessons from a multi-country study in South Africa, Tanzania and Zambia
Comparative, multi-country research has been underutilised as a means to inform health system development. South-south collaboration has been particularly poor, even though there have been clearly identified benefits of such endeavours. This commentary argues that in a context of HIV/AIDS, the need for regional learning has become even greater. This is because of the regional nature of the problem and the unique challenges that it creates for health systems. We draw on the experience of doing comparative research in South Africa, Tanzania and Zambia, to demonstrate that it can be useful for determining preconditions for the success of health care reforms, for affirming common issues faced by countries in the region, and for developing research capacity. Furthermore, these benefits can be derived by all countries participating in such research, irrespective of differences in capacity or socio-economic development
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