236 research outputs found

    Thermodynamic properties of Aharonov-Bohm (AB) and magnetic fields with screened Kratzer potential

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    In this study, the Schrodinger equation (SE) with screened Kratzer potential (SKP) in the presence of external magnetic and AB-flux fields is investigated using the factorization method. The eigenvalue and eigenfunction for the system are obtained in closed form. It is found that the present of the magnetic field partially removes the degeneracy when the screening parameter of the potential was small but the addition of the AB field removed the degeneracy faster and better. The magnetization and magnetic susceptibility of the system are evaluated at zero and finite temperatures and other thermodynamic properties of the system are discussed. More so, the presence of the AB-flux field makes the system to exhibit a both a paramagnetic and diamagnetic behavior. A straight forward extension of these results to three dimension shows that the present result is consistent with those obtained in literature.Comment: 30 pages, 9 figures. arXiv admin note: text overlap with arXiv:1911.0199

    Mechanical characteristics of groundnut shell particle reinforced polylactide nano fibre

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    ABSTRACT The PLA-groundnut shell solution is electrospun to produce nanocomposite fibre. The spinneret containing the composite solution was placed 24.7 cm away from the aluminium collector, tilted at an angle of 30 °, and the solution flow rate kept at 1 mL/min. Groundnut Shell particle (GSP) weight fraction used was varied from 3 - 8 wt. %. Particle reinforced nanofibres were formed on the collector from the composite solution at 26 kV. These nanofibres were subjected to tensile test and the result indicates that at 6 wt. % untreated GSP reinforced fibre possessed the best tensile stiffness of 24.62 MPa. This corresponds to 2.201 % increase in Modulus of Elasticity over the unreinforced PLA (1.07 MPa). The 7 wt. % treated GSP fibre showed the least stiffness (0.33 MPa), which is 69 % reduction over that of unreinforced fibre. PLA fibre reinforced with 5 wt. % untreated GSP displayed best blend of properties over the unreinforced with increase of 286 % (4.43 x 10-4 HB), 1,502 % (1.07 MPa), 286 % (0.22 MPa), 6.8 % (0.05 J) and 1,081 % (~ 0.15 MPa) in hardness, stiffness, UTS, energy at break and stress at break respectively. However, ductility decreased by ~33.3 % when compared to the unreinforced (18.27). The 5 wt. % untreated GSP PLA reinforced fibre showed the highest UTS (0.855 MPa). The micrographs showed beads on reinforced fibres, while the virgin PLA showed no beads

    Prevalence and outcomes of atrial fibrillation in older people living in care homes in Wales:a routine data linkage study 2003-2018

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    OBJECTIVE: To determine atrial fibrillation (AF) prevalence and temporal trends, and examine associations between AF and risk of adverse health outcomes in older care home residents. METHODS: Retrospective cohort study using anonymised linked data from the Secure Anonymised Information Linkage Databank on CARE home residents in Wales with AF (SAIL CARE-AF) between 2003 and 2018. Fine-Gray competing risk models were used to estimate the risk of health outcomes with mortality as a competing risk. Cox regression analyses were used to estimate the risk of mortality. RESULTS: There were 86,602 older care home residents (median age 86.0 years [interquartile range 80.8–90.6]) who entered a care home between 2003 and 2018. When the pre-care home entry data extraction was standardised, the overall prevalence of AF was 17.4% (95% confidence interval 17.1–17.8) between 2010 and 2018. There was no significant change in the age- and sex-standardised prevalence of AF from 16.8% (15.9–17.9) in 2010 to 17.0% (16.1–18.0) in 2018. Residents with AF had a significantly higher risk of cardiovascular mortality (adjusted hazard ratio [HR] 1.27 [1.17–1.37], P < 0.001), all-cause mortality (adjusted HR 1.14 [1.11–1.17], P < 0.001), ischaemic stroke (adjusted sub-distribution HR 1.55 [1.36–1.76], P < 0.001) and cardiovascular hospitalisation (adjusted sub-distribution HR 1.28 [1.22–1.34], P < 0.001). CONCLUSIONS: Older care home residents with AF have an increased risk of adverse health outcomes, even when higher mortality rates and other confounders are accounted for. This re-iterates the need for appropriate oral anticoagulant prescription and optimal management of cardiovascular co-morbidities, irrespective of frailty status and predicted life expectancy

    Standard set of health outcome measures for older persons

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    Background: The International Consortium for Health Outcomes Measurement (ICHOM) was founded in 2012 to propose consensus-based measurement tools and documentation for different conditions and populations.This article describes how the ICHOM Older Person Working Group followed a consensus-driven modified Delphi technique to develop multiple global outcome measures in older persons. The standard set of outcome measures developed by this group will support the ability of healthcare systems to improve their care pathways and quality of care. An additional benefit will be the opportunity to compare variations in outcomes which encourages and supports learning between different health care systems that drives quality improvement. These outcome measures were not developed for use in research. They are aimed at non researchers in healthcare provision and those who pay for these services. Methods: A modified Delphi technique utilising a value based healthcare framework was applied by an international panel to arrive at consensus decisions.To inform the panel meetings, information was sought from literature reviews, longitudinal ageing surveys and a focus group. Results: The outcome measures developed and recommended were participation in decision making, autonomy and control, mood and emotional health, loneliness and isolation, pain, activities of daily living, frailty, time spent in hospital, overall survival, carer burden, polypharmacy, falls and place of death mapped to a three tier value based healthcare framework. Conclusions: The first global health standard set of outcome measures in older persons has been developed to enable health care systems improve the quality of care provided to older persons

    Postnatal PPARδ Activation and Myostatin Inhibition Exert Distinct yet Complimentary Effects on the Metabolic Profile of Obese Insulin-Resistant Mice

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    BACKGROUND: Interventions for T2DM have in part aimed to mimic exercise. Here, we have compared the independent and combined effects of a PPARdelta agonist and endurance training mimetic (GW501516) and a myostatin antibody and resistance training mimetic (PF-879) on metabolic and performance outcomes in obese insulin resistant mice. METHODOLOGY/PRINCIPAL FINDINGS: Male ob/ob mice were treated for 6 weeks with vehicle, GW501516, PF-879, or GW501516 in combination with PF-879. The effects of the interventions on body composition, glucose homeostasis, glucose tolerance, energy expenditure, exercise capacity and metabolic gene expression were compared at the end of study. GW501516 attenuated body weight and fat mass accumulation and increased the expression of genes of oxidative metabolism. In contrast, PF-879 increased body weight by driving muscle growth and altered the expression of genes involved in insulin signaling and glucose metabolism. Despite their differences, both interventions alone improved glucose homeostasis. Moreover, GW501516 more effectively improved serum lipids, and PF-879 uniquely increased energy expenditure, exercise capacity and adiponectin levels. When combined the robust effects of GW501516 and/or PF-879 on body weight, adiposity, muscle mass, glycemia, serum lipids, energy expenditure and exercise capacity were highly conserved. CONCLUSIONS/SIGNIFICANCE: The data, for the first time, demonstrate postnatal inhibition of myostatin not only promotes gains in muscle mass similar to resistance training,but improves metabolic homeostasis. In several instances, these effects were either distinct from or complimentary to those of GW501516. The data further suggest that strategies to increase muscle mass, and not necessarily oxidative capacity, may effectively counter insulin resistance and T2DM

    Long-term correction of diabetes in rats after lentiviral hepatic insulin gene therapy

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    Aims/hypothesis: Type 1 diabetes results from the autoimmune destruction of pancreatic beta cells. Exogenous insulin therapy cannot achieve precise physiological control of blood glucose concentrations, and debilitating complications develop. Lentiviral vectors are promising tools for liver-directed gene therapy. However, to date, transduction rates in vivo remain low in hepatocytes, without the induction of cell cycling. We investigated long-term transgene expression in quiescent hepatocytes in vitro and determined whether the lentiviral delivery of furin-cleavable insulin to the liver could reverse diabetes in rats. Materials and methods: To improve transduction efficiency in vitro, we optimised hepatocyte isolation and maintenance protocols and, using an improved surgical delivery method, delivered furin-cleavable insulin alone or empty vector to the livers of streptozotocin-induced diabetic rats by means of a lentiviral vector. Rats were monitored for changes in body weight and blood glucose, and intravenous glucose tolerance tests were performed. Expression of insulin was determined by RT-PCR, immunohistochemistry and electron microscopy. Results: We achieved long-term transgene expression in quiescent hepatocytes in vitro (87 ± 1.2% transduction efficiency), with up to 60 ± 3.2% transduction in vivo. We normalised blood glucose for 500 days-a significantly longer period than previously reported-making this the first successful study using a lentiviral vector. This procedure resulted in the expression of genes encoding several beta cell transcription factors, some pancreatic endocrine transdifferentiation, hepatic insulin storage in granules, and restoration of glucose tolerance. Liver function tests remained normal. Importantly, pancreatic exocrine transdifferentiation did not occur. Conclusions/interpretation: Our data suggest that this regimen may ultimately be employed for the treatment of type 1 diabetes

    The complex genetic landscape of familial MDS and AML reveals pathogenic germline variants.

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    The inclusion of familial myeloid malignancies as a separate disease entity in the revised WHO classification has renewed efforts to improve the recognition and management of this group of at risk individuals. Here we report a cohort of 86 acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) families with 49 harboring germline variants in 16 previously defined loci (57%). Whole exome sequencing in a further 37 uncharacterized families (43%) allowed us to rationalize 65 new candidate loci, including genes mutated in rare hematological syndromes (ADA, GP6, IL17RA, PRF1 and SEC23B), reported in prior MDS/AML or inherited bone marrow failure series (DNAH9, NAPRT1 and SH2B3) or variants at novel loci (DHX34) that appear specific to inherited forms of myeloid malignancies. Altogether, our series of MDS/AML families offer novel insights into the etiology of myeloid malignancies and provide a framework to prioritize variants for inclusion into routine diagnostics and patient management
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