Circular business advantage: what organisations need to know

This is the author accepted manuscript. The final version is available from the publisher via the link in this recor

The regenerative supply chain: a framework for developing circular economy indicators

This is the final version. Available on open access from Taylor & Francis via the DOI in this recordThere are widely differing experiences and practices in the development of indicators to monitor, report and communicate progress towards the implementation of the circular economy (CE). We present a framework for developing CE indicators which link to the core goals, principles and building blocks of a CE. To do this we utilise the Ellen MacArthur Foundation butterfly model as a coherent systems overview of key material stocks and flows, and representation of relationships between inputs, outputs, recovery processes, emissions, energy and value loops in physical and financial measures which constitute the CE supply chain. Based on nine multinational organisations and four cases of leading companies engaged with CE activity, we address the types of indicators being used and make recommendations for indicators to reflect key goals and principles of CE. Our research on the development and expansion of circular practices leads to the question of what new opportunities and challenges CE raises for such companies in terms of competitive business advantage and resultant requirements for supply chain redesign and indicator development, over and above pre-existing closed-loop production.This work was supported by Engineering and Physical Sciences Research Council [grant number EP/P008941/1 Modelling supply chain optimisation i]

Characterisation of a chimeric Phanerochaete chrysosporium cellobiohydrolase expressed from Escherichia coli

The aim of this study was to purify and analyse a Phanerochaete chrysosporium cbhI.1 gene-product expressed as an inducible, secreted, heterologous protein from an Escerichia coli pGEXcbhI.1 clone. Using glutathione Sepharose 4B affinity chromatography, the expressed protein was purified from the supernatant of an induced E. coli transformed with pGEXcbhI.1 and ran as a single band on a Sodium dodecyl sulphate-polyacrylamide gel. The glutathione S-transferase (GST) fused CBHI.1 was approx-imately 80 kDa in size, approximately 2.2 kDa smaller than the theoretically predicted size. The purified protein exhibited time dependent hydrolytic reaction against carboxy-methyl-cellulose (CMC) and Avicel. On CMC the highest hydrolytic reaction occurred at 120 min. whereas for Avicel it was at 150 min. Optimum pH and temperature for activity of the protein against these cellulose substrates were pH 6 and 55oC, respectively, and the protein remained stable under these optimum conditions for 24 h. Key Words: Phanerochaete chrysosporium, cellobiohydrolase purification, heterologus expression. African Journal of Biotechnology Vol.3(7) 2004: 349-35

Performance-based contracting in the defence industry: Exploring triadic dynamics between government, OEMs and suppliers

This study takes a rare longitudinal perspective to examine performance-based contracting (PBC) in the context of the development of a major capital defence project. It employs a triadic framework to examine changes in actors and their roles over time in fulfilling the project. The triads involve both contractors as suppliers and government entities. More specifically, using a historical narrative method the study suggests that over the 30 year span of the new warship’s development, different parties occupy the nodes of triads where the roles or functions of the principal and agents in the contract change over time. Our use of a triadic perspective enables us to trace both the withdrawal of the government customer from a position of authority and the specific strategy of one supplier to occupy the vacated role as systems integrator. The study makes three distinct contributions: firstly, to our understanding of PBC through tracing the development of the conditions that enable PBC in largescale long-term public-private contracting such as clear role delineation. Second, it adds to understanding of principal-agent behaviour in triadic public-private projects, suggesting that customer and supplier roles need to be perceived as supply network dynamics. Third, it suggests reasons why this defence acquisition underperformed, focusing on the mediation of the customer’s value requirement through powerful players seeking to extend their control. We argue PBC must be re-assessed in complex environments to include less direct financial measures such as long-term market share and adopt a more nuanced approach to contractual management than simply transferring risk.We wish to acknowledge the financial assistance provided by the Chartered Institute of Purchasing & Supply and the Institute of Supply Management

A Capability Maturity Model for the Circular Economy: An Agri-food Perspective

This is the final version. The presentation is available via the link in this recordEngineering and Physical Sciences Research Council (EPSRC

Hierarchical statistical techniques are necessary to draw reliable conclusions from analysis of isolated cardiomyocyte studies

Aims It is generally accepted that post-MI heart failure (HF) changes a variety of aspects of sarcoplasmic reticular Ca2+ fluxes but for some aspects there is disagreement over whether there is an increase or decrease. The commonest statistical approach is to treat data collected from each cell as independent, even though they are really clustered with multiple likely similar cells from each heart. In this study, we test whether this statistical assumption of independence can lead the investigator to draw conclusions that would be considered erroneous if the analysis handled clustering with specific statistical techniques (hierarchical tests). Methods and results Ca2+ transients were recorded in cells loaded with Fura-2AM and sparks were recorded in cells loaded with Fluo-4AM. Data were analysed twice, once with the common statistical approach (assumption of independence) and once with hierarchical statistical methodologies designed to allow for any clustering. The statistical tests found that there was significant hierarchical clustering. This caused the common statistical approach to underestimate the standard error and report artificially small P values. For example, this would have led to the erroneous conclusion that time to 50% peak transient amplitude was significantly prolonged in HF. Spark analysis showed clustering, both within each cell and also within each rat, for morphological variables. This means that a three-level hierarchical model is sometimes required for such measures. Standard statistical methodologies, if used instead, erroneously suggest that spark amplitude is significantly greater in HF and spark duration is reduced in HF. Conclusion Ca2+ fluxes in isolated cardiomyocytes show so much clustering that the common statistical approach that assumes independence of each data point will frequently give the false appearance of statistically significant changes. Hierarchical statistical methodologies need a little more effort, but are necessary for reliable conclusions. We present cost-free simple tools for performing these analyses

Probing elastic and inelastic breakup contributions to intermediate-energy two-proton removal reactions

The two-proton removal reaction from 28Mg projectiles has been studied at 93 MeV/u at the NSCL. First coincidence measurements of the heavy 26Ne projectile residues, the removed protons and other light charged particles enabled the relative cross sections from each of the three possible elastic and inelastic proton removal mechanisms to be determined. These more final-state-exclusive measurements are key for further interrogation of these reaction mechanisms and use of the reaction channel for quantitative spectroscopy of very neutron-rich nuclei. The relative and absolute yields of the three contributing mechanisms are compared to reaction model expectations - based on the use of eikonal dynamics and sd-shell-model structure amplitudes.Comment: Accepted for publication in Physical Review C (Rapid Communication

Elastic breakup cross sections of well-bound nucleons

The 9Be(28Mg,27Na) one-proton removal reaction with a large proton separation energy of Sp(28Mg)=16.79 MeV is studied at intermediate beam energy. Coincidences of the bound 27Na residues with protons and other light charged particles are measured. These data are analyzed to determine the percentage contributions to the proton removal cross section from the elastic and inelastic nucleon removal mechanisms. These deduced contributions are compared with the eikonal reaction model predictions and with the previously measured data for reactions involving the re- moval of more weakly-bound protons from lighter nuclei. The role of transitions of the proton between different bound single-particle configurations upon the elastic breakup cross section is also quantified in this well-bound case. The measured and calculated elastic breakup fractions are found to be in good agreement.Comment: Phys. Rev. C 2014 (accepted

Temporal trends and lesion sets for persistent atrial fibrillation ablation: a meta-analysis with trial sequential analysis and meta-regression

BACKGROUND: Ablation for persistent atrial fibrillation (PsAF) has been performed for over 20 years, although success rates have remained modest. Several adjunctive lesion sets have been studied but none have become standard of practice. We sought to describe how the efficacy of ablation for PsAF has evolved in this time period with a focus on the effect of adjunctive ablation strategies. METHODS: Databases were searched for prospective studies of PsAF ablation. We performed meta-regression and trial sequential analysis. RESULTS: A total of 99 studies (15 424 patients) were included. Ablation for PsAF achieved the primary outcome (freedom of atrial fibrillation/atrial tachycardia rate at 12 months follow-up) in 48.2% (5% CI, 44.0-52.3). Meta-regression showed freedom from atrial arrhythmia at 12 months has improved over time, while procedure time and fluoroscopy time have significantly reduced. Through the use of cumulative meta-analyses and trial sequential analysis, we show that some ablation strategies may initially seem promising, but after several randomized controlled trials may be found to be ineffective. Trial sequential analysis showed that complex fractionated atrial electrogram ablation is ineffective and further study of this treatment would be futile, while posterior wall isolation currently does not have sufficient evidence for routine use in PsAF ablation. CONCLUSIONS: Overall success rates from PsAF ablation and procedure/fluoroscopy times have improved over time. However, no adjunctive lesion set, in addition to pulmonary vein isolation, has been conclusively demonstrated to be beneficial. Through the use of trial sequential analysis, we highlight the importance of adequately powered randomized controlled trials, to avoid reaching premature conclusions, before widespread adoption of novel therapies

The Epidemiology of Lead Toxicity in Adults: Measuring Dose and Consideration of Other Methodologic Issues

We review several issues of broad relevance to the interpretation of epidemiologic evidence concerning the toxicity of lead in adults, particularly regarding cognitive function and the cardiovascular system, which are the subjects of two systematic reviews that are also part of this mini-monograph. Chief among the recent developments in methodologic advances has been the refinement of concepts and methods for measuring individual lead dose in terms of appreciating distinctions between recent versus cumulative doses and the use of biological markers to measure these parameters in epidemiologic studies of chronic disease. Attention is focused particularly on bone lead levels measured by K-shell X-ray fluorescence as a relatively new biological marker of cumulative dose that has been used in many recent epidemiologic studies to generate insights into lead’s impact on cognition and risk of hypertension, as well as the alternative method of estimating cumulative dose using available repeated measures of blood lead to calculate an individual’s cumulative blood lead index. We review the relevance and interpretation of these lead biomarkers in the context of the toxico-kinetics of lead. In addition, we also discuss methodologic challenges that arise in studies of occupationally and environmentally exposed subjects and those concerning race/ethnicity and socioeconomic status and other important covariates