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"Needham, Paul"
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Institutional repositories and the item and research data metrics landscape
by
Lambert, Jo
,
Needham, Paul
in
COUNTER
,
Information management
,
Information storage and retrieval systems
2019
The success of COUNTER in supporting adoption of a standard to measure e-resource usage over the past 15 years is apparent within the scholarly communications community. The prevalence of global OA policies and mandates, and the role of institutional repositories within this context, prompts demand for more granular metrics. It also raises the profile of data sharing of item-level usage and research data metrics. The need for reliable and authoritative measures is paramount. This burgeoning interest is complemented by a number of initiatives to explore the measurement and tracking of usage of a broad range of objects outside traditional publisher platforms. Drawing on examples such as OpenAIRE, IRUS-UK, Crossref's Distributed Usage Logging and Event Data service and COAR Next Generation Repositories, this article provides a brief introduction and overview of developments in this area.
Journal Article
Thermodynamics of an Empty Box
by
Schmitz, Georg J.
,
Ellingsen, Lodin
,
Needham, Paul
in
Algebra
,
Analysis
,
anisotropic Hubble parameter
2023
A gas in a box is perhaps the most important model system studied in thermodynamics and statistical mechanics. Usually, studies focus on the gas, whereas the box merely serves as an idealized confinement. The present article focuses on the box as the central object and develops a thermodynamic theory by treating the geometric degrees of freedom of the box as the degrees of freedom of a thermodynamic system. Applying standard mathematical methods to the thermodynamics of an empty box allows equations with the same structure as those of cosmology and classical and quantum mechanics to be derived. The simple model system of an empty box is shown to have interesting connections to classical mechanics, special relativity, and quantum field theory.
Journal Article
Hyperspectral Imaging Sorting of Refurbishment Plasterboard Waste
2023
Post-consumer plasterboard waste sorting is carried out manually by operators, which is time-consuming and costly. In this work, a laboratory-scale hyperspectral imaging (HSI) system was evaluated for automatic refurbishment plasterboard waste sorting. The HSI system was trained to differentiate between plasterboard (gypsum core between two lining papers) and contaminants (e.g., wood, plastics, mortar or ceramics). Segregated plasterboard samples were crushed and sieved to obtain gypsum particles of less than 250 microns, which were characterized through X-ray fluorescence to determine their chemical purity levels. Refurbishment plasterboard waste particles <10 mm in size were not processed with the HSI-based sorting system because the manual processing of these particles at a laboratory scale would have been very time-consuming. Gypsum from refurbishment plasterboard waste particles <10 mm in size contained very small amounts of undesirable chemical impurities for plasterboard manufacturing (chloride, magnesium, sodium, potassium and phosphorus salts), and its chemical purity was similar to that of the gypsum from HSI-sorted plasterboard (96 wt%). The combination of unprocessed refurbishment plasterboard waste <10 mm with HSI-sorted plasterboard ≥10 mm in size led to a plasterboard recovery yield >98 wt%. These findings underpin the potential implementation of an industrial-scale HSI system for plasterboard waste sorting.
Journal Article
Determining Sameness of Substance
2017
The idea that the extension of a chemical substance is fixed by determining what stands in the relation of being the same substance to a paradigm sample plays a substantial role in chemistry, and procedures of identification that don't make direct use of the method can be traced back to ones that do. But paradigm samples are not typically selected by ostension, as in Putnam's version of this procedure. The relevance of ostension is questioned after a discussion of the establishment of paradigm specimens in the analysis of some contents of crude oil and an examination of the general features of the samesubstance relation that takes into account the temporal dependency and the consequent role of characteristic features of substances.
Journal Article
Microessentialism: What is the Argument?
2011
According to microessentialism, it is necessary to resort to microstructure in order to adequately characterise chemical substances such as water. But the thesis has never been properly supported by argument. Kripke and Putnam, who originally proposed the thesis, suggest that a so-called stereotypical characterisation is not possible, whereas one in terms of microstructure is. However, the sketchy outlines given of stereotypical descriptions hardly support the impossibility claim. On the other hand, what naturally stands in contrast to microscopic description is description in macroscopic terms, and macroscopic characterisations of water are certainly possible. This suffices to counter the claim that microdescriptions are necessary. Whether it counters the impossibility claim depends on whether all macroscopic descriptions are stereotypical (stereotypical descriptions presumably being macroscopic). In so far as systematic import of \"stereotypical\" can be determined, it would seem not. But some macroscopic characterisations have definite affinity with everyday knowledge, which presumably stands in conflict with the spirit of the impossibility claim. Since what is characterised are properties expressed by predicates like \"is water\", the necessity of identity has no bearing here, and matters of interpretation pose problems for claims to the effect that science fixes the extension of \"water\" as ordinarily understood.
Journal Article
IRUS-UK: making scholarly statistics count in UK repositories
2012
IRUS-UK is a new national standards-based statistics aggregation service for institutional repositories in the UK. The service processes raw usage data from repositories, consolidating those data into COUNTER-compliant statistics by following the rules of the COUNTER Code of Practice – the same code adhered to by the majority of scholarly publishers. This will, for the first time, enable UK repositories to provide consistent, comparable and trustworthy usage data as well as supporting opportunities for benchmarking at a national level. This article provides some context to development, benefits and opportunities offered by the service, an institutional repository perspective and future plans.
Journal Article
Predicting the difficult laparoscopic cholecystectomy: development and validation of a pre-operative risk score using an objective operative difficulty grading system
2020
BackgroundThe prediction of a difficult cholecystectomy has traditionally been based on certain pre-operative clinical and imaging factors. Most of the previous literature reported small patient cohorts and have not used an objective measure of operative difficulty. The aim of this study was to develop a pre-operative score to predict difficult cholecystectomy, as defined by a validated intra-operative difficulty grading scale.MethodTwo cohorts from prospectively maintained databases of patients who underwent laparoscopic cholecystectomy were analysed: the CholeS Study (8755 patients) and a single surgeon series (4089 patients). Factors potentially predictive of difficulty were correlated to the Nassar intra-operative difficulty scale. A multivariable binary logistic regression analysis was then used to identify factors that were independently associated with difficult laparoscopic cholecystectomy, defined as operative difficulty grades 3 to 5. The resulting model was then converted to a risk score, and validated on both internal and external datasets.ResultIncreasing age and ASA classification, male gender, diagnosis of CBD stone or cholecystitis, thick-walled gallbladders, CBD dilation, use of pre-operative ERCP and non-elective operations were found to be significant independent predictors of difficult cases. A risk score based on these factors returned an area under the ROC curve of 0.789 (95% CI 0.773–0.806, p < 0.001) on external validation, with 11.0% versus 80.0% of patients classified as low versus high risk having difficult surgeries.ConclusionWe have developed and validated a pre-operative scoring system that uses easily available pre-operative variables to predict difficult laparoscopic cholecystectomies. This scoring system should assist in patient selection for day case surgery, optimising pre-operative surgical planning (e.g. allocation of the procedure to a suitably trained surgeon) and counselling patients during the consent process. The score could also be used to risk adjust outcomes in future research.
Journal Article
Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy
2019
BackgroundA reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets.MethodsPatient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis.ResultsA higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001).ConclusionWe have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty.
Journal Article
Nineteenth-century chemical theory: correction of a misunderstanding
2014
I reply in this short note to some criticisms that Alan Rocke has recently made in this journal.
Journal Article
Substance and Time
2010
‘Water is H2O’ is naturally construed as an equivalence. What are the things to which the two predicates ‘is water’ and ‘is H2O’ apply? The equivalence presupposes that substance properties are distinguished from phase properties. A substance like water (H2O) exhibits various phases (solid, liquid, gas) under appropriate conditions, and a given (say liquid) phase may comprise several substances. What general features distinguish substance from phase properties? I tackle these questions on the basis of an interpretation of a theorem of thermodynamics known as Gibbs' phase rule which systematically relates these two kinds of feature of matter. The interpretation develops the idea that the things substance and phase predicates apply to are quantities of matter which sustain mereological relations and operations and exploits these mereological features in distinguishing the two kinds of property. Gibbs' phase rule is a macroscopic principle applicable for macroscopic intervals of time. Bringing intervals of time into the picture calls for a more detailed consideration of the relation between macroscopic equilibria and the corresponding dynamic equilibria at the microlevel and throws into question the simple idea that quantities can always be regarded as collections of molecules. The account provides some insight into how the continuous, macroscopic conception of matter (‘gunk’) is reconciled with the discrete microscopic conception and illuminates the interpretation of substances present in mixtures. Introduction Time Dependence Microentities Criteria of Purity and the Notion of Substance Derivation and Further Illustrations of the Phase Rule Microscopic Species in Water Dynamic Equilibria and the Phase Rule The Time of Predication Independent Substances The General Conception of a Mixture Conclusion
Journal Article