2,670 research outputs found

    Patients flow: a mixed-effects modelling approach to predicting discharge probabilities

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    A mixed effects approach hereby introduced to patients flow and length of stay modelling. In, particular, a class of generalized linear mixed models has been used to demonstrate the usefulness of this approach. This modelling technique is used to capture individual patients experience during the process of care as represented by their pathways through the system. The approach could predict the probability of discharge from the system, as well as detect where the system may be going wrong

    Role of proton irradiation and relative air humidity on iron corrosion

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    This paper presents a study of the effects of proton irradiation on iron corrosion. Since it is known that in humid atmospheres, iron corrosion is enhanced by the double influence of air and humidity, we studied the iron corrosion under irradiation with a 45% relative humidity. Three proton beam intensities (5, 10 and 20 nA) were used. To characterise the corrosion layer, we used ion beam methods (Rutherford Backscattering Spectrometry (RBS), Elastic Recoil Detection Analysis (ERDA)) and X-ray Diffraction (XRD) analysis. The corrosion kinetics are plotted for each proton flux. A diffusion model of the oxidant species is proposed, taking into account the fact that the flux through the surface is dependent on the kinetic factor K. This model provides evidence for the dependence of the diffusion coefficient, D, and the kinetic factor, K, on the proton beam intensity. Comparison of the values for D with the diffusion coefficients for thermal oxygen diffusion in iron at 300 K suggests an enhancement due to irradiation of 6 orders of magnitude

    Investigating bacteriophages targeting the opportunistic pathogen Acinetobacter baumannii

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    The multi-drug resistance of the opportunistic pathogen Acinetobacter baumannii is of growing concern, with many clinical isolates proving to be resistant to last resort as well as front line antibiotic treatments. The use of bacteriophages is an attractive alternative to controlling and treating this emerging nosocomial pathogen. In this study, we have investigated bacteriophages collected from hospital wastewater in Thailand and we have explored their activity against clinical isolates of A. baumannii. Bacteriophage vB_AbaM_PhT2 showed 28% host range against 150 multidrug resistant (MDR) isolates and whole genome sequencing did not detect any known virulence factors or antibiotic resistance genes. Purified vB_AbaM_PhT2 samples had endotoxin levels below those recommended for preclinical trials and were not shown to be directly cytotoxic to human cell lines in vitro. The treatment of human brain and bladder cell lines grown in the presence of A. baumannii with this bacteriophage released significantly less lactate dehydrogenase compared to samples with no bacteriophage treatment, indicating that vB_AbaM_PhT2 can protect from A. baumannii induced cellular damage. Our results have also indicated that there is synergy between this bacteriophage and the end line antibiotic colistin. We therefore propose bacteriophage vB_AbaM_PhT2 as a good candidate for future research and for its potential development into a surface antimicrobial for use in hospitals. View Full-Tex

    MePrints: Building User Centred Repositories

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    Over the last few years we have been working to reinvent Teaching and Learning Repositories learning from the best practices of Web 2.0. Over this time we have successfully deployed a number of innovative repositories, including Southampton University EdShare, The Language Box, The HumBox, Open University’s LORO and Worcester Learning Box

    Resonances in rotationally inelastic scattering of OH(X2ΠX^2\Pi) with helium and neon

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    We present detailed calculations on resonances in rotationally and spin-orbit inelastic scattering of OH (X\,^2\Pi, j=3/2, F_1, f) radicals with He and Ne atoms. We calculate new \emph{ab initio} potential energy surfaces for OH-He, and the cross sections derived from these surfaces compare favorably with the recent crossed beam scattering experiment of Kirste \emph{et al.} [Phys. Rev. A \textbf{82}, 042717 (2010)]. We identify both shape and Feshbach resonances in the integral and differential state-to-state scattering cross sections, and we discuss the prospects for experimentally observing scattering resonances using Stark decelerated beams of OH radicals.Comment: 14 pages, 15 Figure

    Fragment-based identification of determinants of conformational and spectroscopic change at the ricin active site

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    <p>Abstract</p> <p>Background</p> <p>Ricin is a potent toxin and known bioterrorism threat with no available antidote. The ricin A-chain (RTA) acts enzymatically to cleave a specific adenine base from ribosomal RNA, thereby blocking translation. To understand better the relationship between ligand binding and RTA active site conformational change, we used a fragment-based approach to find a minimal set of bonding interactions able to induce rearrangements in critical side-chain positions.</p> <p>Results</p> <p>We found that the smallest ligand stabilizing an open conformer of the RTA active site pocket was an amide group, bound weakly by only a few hydrogen bonds to the protein. Complexes with small amide-containing molecules also revealed a switch in geometry from a parallel towards a splayed arrangement of an arginine-tryptophan cation-pi interaction that was associated with an increase and red-shift in tryptophan fluorescence upon ligand binding. Using the observed fluorescence signal, we determined the thermodynamic changes of adenine binding to the RTA active site, as well as the site-specific binding of urea. Urea binding had a favorable enthalpy change and unfavorable entropy change, with a ΔH of -13 ± 2 kJ/mol and a ΔS of -0.04 ± 0.01 kJ/(K*mol). The side-chain position of residue Tyr80 in a complex with adenine was found not to involve as large an overlap of rings with the purine as previously considered, suggesting a smaller role for aromatic stacking at the RTA active site.</p> <p>Conclusion</p> <p>We found that amide ligands can bind weakly but specifically to the ricin active site, producing significant shifts in positions of the critical active site residues Arg180 and Tyr80. These results indicate that fragment-based drug discovery methods are capable of identifying minimal bonding determinants of active-site side-chain rearrangements and the mechanistic origins of spectroscopic shifts. Our results suggest that tryptophan fluorescence provides a sensitive probe for the geometric relationship of arginine-tryptophan pairs, which often have significant roles in protein function. Using the unusual characteristics of the RTA system, we measured the still controversial thermodynamic changes of site-specific urea binding to a protein, results that are relevant to understanding the physical mechanisms of protein denaturation.</p

    Regional policy spillovers : the national impact of demand-side policy in an interregional model of the UK economy

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    UK regional policy has been advocated as a means of reducing regional disparities and stimulating national growth. However, there is limited understanding of the interregional and national effects of such a policy. This paper uses an interregional computable general equilibrium model to identify the national impact of a policy-induced regional demand shock under alternative labour market closures. Our simulation results suggest that regional policy operating solely on the demand side has significant national impacts. Furthermore, the effects on the nontarget region are particularly sensitive to the treatment of the regional labour market

    Reduction en-masse of inguinal hernia with strangulated obstruction

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    “Reduction en masse of inguinal hernia” means reduction/migration of a hernial sac into the properitoneal space. We report the CT findings in a case of reduction en masse with strangulated obstruction. CT scan demonstrated a hernial sac with fibrous constriction band at the neck, situated in the properitoneal space superior to the inguinal region, causing closed-loop obstruction. The hernial sac contained thickened bowel loop with wall enhancement and fluid suggestive of incarceration/strangulation. We propose to call this, ‘The properitoneal hernial sac sign’, defined as “Presence of a hernial sac in the properitoneal space (and not in the inguinal/femoral canal) containing an obstructed/incarcerated bowel loop and causing small bowel obstruction” to identify “reduction en masse of inguinal hernia”

    Maturation of the gastric microvasculature in Xenopus laevis (Lissamphibia, Anura) occurs at the transition from the herbivorous to the carnivorous lifestyle, predominantly by intussuceptive microvascular growth (IMG): a scanning electron microscope study of microvascular corrosion casts and correlative light microscopy

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    The microvascular bed of the stomach of Xenopus laevis and the changes it undergoes when the herbivorous tadpole becomes a carnivorous adult were studied by scanning electron microscopy of vascular corrosion casts and light microscopy of stained tissue sections. In tadpoles an upper and a lower gastric artery supplied, and upper, middle and lower medial and lateral gastric veins drained the vertically extending stomach. During metamorphosis, the stomach gained a horizontal cranio-caudal extension and vessels accordingly become dorsal and ventral gastric arteries, and anterior, middle and posterior gastric veins, respectively. Up to stage 64 (late climax) mucosal capillaries formed a polygonal network of wide immature-looking capillaries ensheathing gastric glands in a basket-like manner. From stage 64 onwards, blood vessels of the stomach appeared mature, revealed a clear hierarchy and were correlated closely with the histomorphology of the stomach, which had also gained the adult pattern. Within the gastric mucosa, ascending arterioles branched in a fountain-like pattern into wide subepithelial capillaries establishing a centripetal blood flow along the gastric glands, which makes an ultrashort control loop of glandular cells within the branched tubular gastric glands very unlikely. Formation of the stomach external muscular layer started at stage 57 when smooth muscle cells locally formed a single longitudinal and one-to-two single circular layers. Abundant signs of intussusceptive microvascular growth and rare vascular sprouts in vascular corrosion casts indicated that the larval-to-adult microvascular pattern formation of the stomach of Xenopus laevis Daudin occurs predominantly by non-sprouting angiogenesis

    Multivisceral intestinal transplantation: Surgical pathology

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    We report the diagnostic surgical pathology of two children who underwent multivisceral abdominal transplantation and survived for 1 month and 6 months. There is little relevant literature, and diagnostic criteria for the various clinical possibilities are not established; this is made more complicated by the simultaneous occurrence of more than one process. We based our interpretations on conventional histology, augmented with immunohistology, including HLA staining that distinguished graft from host cells in situ. In some instances functional analysis of T cells propagated from the same biopsies was available and was used to corroborate morphological interpretations. A wide spectrum of changes was encountered. Graft-versus-host disease, a prime concern before surgery, was not seen. Rejection was severe in 1 patient, not present in the other, and both had evidence of lymphoproliferative disease, which was related to Epstein-Barr virus. Bacterial translocation through the gut wall was also a feature in both children. This paper documents and illustrates the various diagnostic possibilities.. © 1989 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted
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