436 research outputs found
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A Newly Discovered Poem by Erasmus
A previously unknown poem by Desiderius Erasmus (1466-1536) has come to light in Cambridge University Library’s copy of the first collected edition of his epigrams. The book in which it was found was printed not as a separate work, but as the third part of a collection superintended by Erasmus and mainly consisting of the writings of Thomas More. For the chief item in it was More’s Utopia, supplemented first by More’s epigrams, and then by those of Erasmus. The volume is therefore catalogued at Cambridge as De optimo reip. statu, deque noua insula Vtopia (Basel: Froben, March 1518; classmark Rel.c.51.3). It is continuously paginated, and in the final section an early Tudor hand has copied into the margins three poems, all of them expressly ascribed to Erasmus. The first of them, described as an epitaph on King Henry VII (and inserted on page 319), has hitherto been unknown to modern scholars. The other two poems (inserted on page 355) both relate to Henry VIII’s meeting with the Emperor Charles V at Calais in July 1520.This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by Leuven University Press
Enhancement of thrust reverser cascade performance using aerodynamic and structural integration
This paper focuses on the design of a cascade within a cold stream thrust reverser during the early, conceptual stage of the product development process. A reliable procedure is developed for the exchange of geometric and load data between a two dimensional aerodynamic model and a three dimensional structural model. Aerodynamic and structural simulations are carried out using realistic operating conditions, for three different design configurations with a view to minimising weight for equivalent or improved aerodynamic and structural performance. For normal operational conditions the simulations show that total reverse thrust is unaffected when the performance of the deformed vanes is compared to the un-deformed case. This shows that for the conditions tested, the minimal deformation of the cascade vanes has no significant affect on aerodynamic efficiency and that there is scope for reducing the weight of the cascade. The pressure distribution through a two dimensional thrust reverser section is determined for two additional cascade vane configurations and it is shown that with a small decrease in total reverse thrust, it is possible to reduce weight and eliminate supersonic flow regimes through the nacelle section. By increasing vane sections in high pressure areas and decreasing sections in low pressure areas the structural performance of the cascade vanes in the weight reduced designs, is improved with significantly reduced levels of vane displacement and stress
Experimental Investigation into the Influence of Backfill Types on the Vibro-acoustic Characteristics of Leaks in MDPE Pipe
Pipe leak location estimates are commonly conducted using Vibro-Acoustic Emission (VAE) based methods, usually using accelerometers or hydrophones. Successful estimation of a leak's location is dependent on a number of factors, including the speed of sound, resonance, backfill, reflections from other sources, leak shape and size. However, despite some investigation into some of the aforementioned factors, the influence of backfill type on a leak's VAE signal has still not been experimentally quantified. A limited number of studies have attempted to quantify the effects of backfill. However, all of these studies couple other variables which could be equally responsible for their observed changes in leak signal. There have been no controlled studies where one variable can be directly compared to one another (i.e. all variables remain constant, only changing backfill type). The aim of this paper is to better characterise the influence of backfill on a leak's VAE signal by individually isolating all variables. For the first time, this paper demonstrates the influence of backfill on leak VAE signal by keeping all other variables consistent. It was found that the backfill type had a strong influence on the frequency and amplitude of leak signals, which is likely to have a significant impact on the accuracy of leak location estimates
The potential to quantify polypharmacy in older adult hospital inpatients using electronic prescribing software: A feasibility study
Polypharmacy in older adults is a growing problem, as some drugs may be either unnecessary or even harmful. Admission to hospital under a Medicine for the Elderly specialist physicians represents an opportunity to review patients’ medication. The recent introduction of electronic prescribing to some hospitals in the United Kingdom allows the development of tools to measure polypharmacy in in-patients, and subsequently to assess the efficacy of interventions that aim to optimize medication prescribing. We tested the feasibility of developing an Excel-based software code that measured the number of medications a group of patients were taking at admission and how many of these were still prescribed on discharge. Electronic prescribing data was obtained from the Royal Derby Hospital, over a period of 52 weeks from April 2017 to March 2018 for all patients over the age of 65 years who were admitted onto the medicine for the elderly wards and subsequently discharged. On admission, the median number of eligible medications was 11 (interquartile range IQR 8 to 15). At the time of discharge, the median number of eligible medications retained since admission was 9 (IQR 6 to 12). This represents a median number of medications that have been removed from the current medication regimen of 2 (IQR 1 to 3, p [less than] 0.001). Electronic prescribing software in hospitals allows the development of tools to measure the burden of medications, and to examine the efficacy of future interventions that are developed to optimize drug prescribing in older adults
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Controls on inorganic nitrogen leaching from Finnish catchments assessed using a sensitivity and uncertainty analysis of the INCA -N model
The semi-distributed, dynamic INCA-N model was used to simulate the behaviour of dissolved inorganic nitrogen (DIN) in two Finnish research catchments. Parameter sensitivity and model structural uncertainty were analysed using generalized sensitivity analysis. The Mustajoki catchment is a forested upstream catchment, while the Savijoki catchment represents intensively cultivated lowlands. In general, there were more influential parameters in Savijoki than Mustajoki. Model results were sensitive to N-transformation rates, vegetation dynamics, and soil and river hydrology. Values of the sensitive parameters were based on long-term measurements covering both warm and cold years. The highest measured DIN concentrations fell between minimum and maximum values estimated during the uncertainty analysis. The lowest measured concentrations fell outside these bounds, suggesting that some retention processes may be missing from the current model structure. The lowest concentrations occurred mainly during low flow periods; so effects on total loads were small
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Parameters associated with efficacy of epidural steroid injections in the management of postherpetic neuralgia: the Mayo Clinic experience
Purpose: Thirty percent of patients with postherpetic neuralgia (PHN) receiving conservative treatment report unsatisfactory pain relief. Epidural steroid injections (ESIs) are commonly used as a therapeutic intervention in these patients. In this study, we aimed to determine if there are variables that predict the efficacy of ESI in patients with PHN. Patients and methods: We retrospectively identified patients seen at Mayo Clinic who had PHN and received ESI. From their medical records, we abstracted the demographic variables, concurrent medication use, anatomic approach and medication for ESI, and degree of pain relief at 2 and 12 weeks' postintervention. Results: None of the studied variables were significantly associated with efficacy of ESI in patients with PHN. PHN that began < 11 months before treatment was predictive of a response to ESI at 12 weeks postintervention (positive predictive value, 55%). Patients who reported poor ESI efficacy 2 weeks after the intervention had a 94% chance of still having pain at 12 weeks. Conclusion: For this cohort of patients with PHN being treated with ESI, no demographic characteristics, concurrently used medications, or type of ESI were associated with ESI treatment efficacy at 2 or 12 weeks after the intervention.Open Access JournalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Prediction of leak flow rate in plastic water distribution pipes using vibro-acoustic measurements
Leakage from water distribution systems is a worldwide issue with consequences including loss of revenue, health and environmental concerns. Leaks have typically been found through leak noise correlation by placing sensors either side of the leak and recording and analysing its vibro-acoustic emission. While this method is widely used to identify the location of the leak, the sensors also record data that could be related to the leak’s flow rate, yet no reliable method exists to predict leak flow rate in water distribution pipes using vibro-acoustic emission. The aim of this research is to predict leak flow rate in medium-density polyethylene pipe using vibro-acoustic emission signals. A novel experimental methodology is presented whereby circular holes of four sizes are tested at several leak flow rates. Following the derivation of a number of features, least squares support vector machines are used in order to predict leak flow rate. The results show a strong correlation highlighting the potential of this technique as a rapid and practical tool for water companies to assess and prioritise leak repair
Compilation and Network Analyses of Cambrian Food Webs
A rich body of empirically grounded theory has developed about food webs—the networks of feeding relationships among species within habitats. However, detailed food-web data and analyses are lacking for ancient ecosystems, largely because of the low resolution of taxa coupled with uncertain and incomplete information about feeding interactions. These impediments appear insurmountable for most fossil assemblages; however, a few assemblages with excellent soft-body preservation across trophic levels are candidates for food-web data compilation and topological analysis. Here we present plausible, detailed food webs for the Chengjiang and Burgess Shale assemblages from the Cambrian Period. Analyses of degree distributions and other structural network properties, including sensitivity analyses of the effects of uncertainty associated with Cambrian diet designations, suggest that these early Paleozoic communities share remarkably similar topology with modern food webs. Observed regularities reflect a systematic dependence of structure on the numbers of taxa and links in a web. Most aspects of Cambrian food-web structure are well-characterized by a simple “niche model,” which was developed for modern food webs and takes into account this scale dependence. However, a few aspects of topology differ between the ancient and recent webs: longer path lengths between species and more species in feeding loops in the earlier Chengjiang web, and higher variability in the number of links per species for both Cambrian webs. Our results are relatively insensitive to the exclusion of low-certainty or random links. The many similarities between Cambrian and recent food webs point toward surprisingly strong and enduring constraints on the organization of complex feeding interactions among metazoan species. The few differences could reflect a transition to more strongly integrated and constrained trophic organization within ecosystems following the rapid diversification of species, body plans, and trophic roles during the Cambrian radiation. More research is needed to explore the generality of food-web structure through deep time and across habitats, especially to investigate potential mechanisms that could give rise to similar structure, as well as any differences
The role of charge in the toxicity of polymer-coated cerium oxide nanomaterials to Caenorhabditis elegans
This study examined the impact of surface functionalization and charge on ceria nanomaterial toxicity to Caenorhabditis elegans. The examined endpoints included mortality, reproduction, protein expression, and protein oxidation profiles. Caenorhabditis elegans were exposed to identical 2–5 nm ceria nanomaterial cores which were coated with cationic (diethylaminoethyl dextran; DEAE), anionic (carboxymethyl dextran; CM), and non-ionic (dextran; DEX) polymers. Mortality and reproductive toxicity of DEAE-CeO2 was approximately two orders of magnitude higher than for CM-CeO2 or DEX-CeO2. Two-dimensional gel electrophoresis with orbitrap mass spectrometry identification revealed changes in the expression profiles of several mitochondrial-related proteins and proteins that are expressed in the C. elegans intestine. However, each type of CeO2 material exhibited a distinct protein expression profile. Increases in protein carbonyls and protein-bound 3-nitrotyrosine were also observed for some proteins, indicating oxidative and nitrosative damage. Taken together the results indicate that the magnitude of toxicity and toxicity pathways vary greatly due to surface functionalization of CeO2 nanomaterials
Does location matter? Characterisation of the anatomic locations, molecular profiles, and clinical features of gliomas
Background. Neuroanatomic locations of gliomas may influence clinical presentations, molecular profiles, and patients’ prognoses. Methods. We investigated our institutional cancer registry to include patients with glioma over a 10-year period. Statistical tests were used to compare demographic, genetic, and clinical characteristics among patients with gliomas in different locations. Survival analysis methods were then used to assess associations between location and overall survival in the full cohort, as well as in relevant subgroups. Results. 182 gliomas were identified. Of the tumours confined to a single lobe, there were 51 frontal (28.0%), 50 temporal (27.5%), 22 parietal (12.1%), and seven occipital tumours (3.8%) identified. Tumours affecting the temporal lobe were associated with reduced overall survival when compared to all other tumours (11 months vs. 13 months, log-rank p = 0.0068). In subgroup analyses, this result was significant for males [HR (95%CI) 2.05 (1.30, 3.24), p = 0.002], but not for females [HR (95%CI) 1.12 (0.65, 1.93), p = 0.691]. Out of 82 cases tested for IDH-1, 10 were mutated (5.5%). IDH-1 mutation was present in six frontal, two temporal, one thalamic, and one multifocal tumour. Out of 21 cases tested for 1p19q deletions, 12 were co-deleted, nine of which were frontal lobe tumours. MGMT methylation was assessed in 45 cases; 7/14 frontal tumours and 6/13 temporal tumours were methylated. Conclusion. Our results support the hypothesis that the anatomical locations of gliomas influence patients’ clinical courses. Temporal lobe tumours were associated with poorer survival, though this association appeared to be driven by these patients’ more aggressive tumour profiles and higher risk baseline demographics. Independently, female patients who had temporal lobe tumours fared better than males. Molecular analysis was limited by the low prevalence of genetic testing in the study sample, highlighting the importance of capturing this information for all gliomas. Importance of this study. The specific neuroanatomic location of tumours in the brain is thought to be predictive of treatment options and overall prognosis. Despite evidence for the clinical significance of this information, there is relatively little information available regarding the incidence and prevalence of tumours in the different anatomical regions of the brain. This study has more fully characterised tumour prevalence in different regions of the brain. Additionally, we have analysed how this information may affect tumours’ molecular characteristics, treatment options offered to patients, and patients’ overall survival. This information will be informative both in the clinical setting and in directing future research
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