MILP approaches to sustainable production and distribution of meal elements

This paper studies the production and distribution system forprofessionally prepared meals, in which a new innovative concept is applied. Theconcept aims to improve the sustainability of the system by distributing mealelements super-chilled in the conventional cold chain. Here, sustainabilitycomprises economic, environmental and social aspects. The impacts on andtrade-offs between the different dimensions of sustainability are discussed, andcombined with aspect of product quality. Furthermore, we identify the importantplanning decisions in relation to production and distribution and organisethese in a decision hierarchy. Based on these discussions, decision supportmodels based on mixed-integer linear programming are developed for the planningtasks on the tactical level, including decision-making on packaging options anddelivery structures. The resulting models can be used to support production anddistribution planning, and also evaluate the performance of and quantify thetrade-offs between the different sustainability dimensions.</p

Simulation in manufacturing and business: A review

Copyright @ 2009 Elsevier B.V.This paper reports the results of a review of simulation applications published within peer-reviewed literature between 1997 and 2006 to provide an up-to-date picture of the role of simulation techniques within manufacturing and business. The review is characterised by three factors: wide coverage, broad scope of the simulation techniques, and a focus on real-world applications. A structured methodology was followed to narrow down the search from around 20,000 papers to 281. Results include interesting trends and patterns. For instance, although discrete event simulation is the most popular technique, it has lower stakeholder engagement than other techniques, such as system dynamics or gaming. This is highly correlated with modelling lead time and purpose. Considering application areas, modelling is mostly used in scheduling. Finally, this review shows an increasing interest in hybrid modelling as an approach to cope with complex enterprise-wide systems

Strengthening the United Nations Secretary-General’s Mechanism to an alleged use of bioweapons through a quality-assured laboratory response

The cascade of innovations in biotechnology opens new pathways for biological warfare. The international laboratory network being developed under the UN Secretary-General’s Mechanism could provide vital evidence in case of an alleged biological attack.Peer Reviewe

Mobilisation of critically ill patients receiving norepinephrine: a retrospective cohort study

Background: Mobilisation and exercise intervention in general are safe and feasible in critically ill patients. For patients requiring catecholamines, however, doses of norepinephrine safe for mobilisation in the intensive care unit (ICU) are not defined. This study aimed to describe mobilisation practice in our hospital and identify doses of norepinephrine that allowed a safe mobilisation. Methods: We conducted a retrospective single-centre cohort study of 16 ICUs at a university hospital in Germany with patients admitted between March 2018 and November 2021. Data were collected from our patient data management system. We analysed the effect of norepinephrine on level (ICU Mobility Scale) and frequency (units per day) of mobilisation, early mobilisation (within 72 h of ICU admission), mortality, and rate of adverse events. Data were extracted from free-text mobilisation entries using supervised machine learning (support vector machine). Statistical analyses were done using (generalised) linear (mixed-effect) models, as well as chi-square tests and ANOVAs. Results: A total of 12,462 patients were analysed in this study. They received a total of 59,415 mobilisation units. Of these patients, 842 (6.8%) received mobilisation under continuous norepinephrine administration. Norepinephrine administration was negatively associated with the frequency of mobilisation (adjusted difference -0.07 mobilisations per day; 95% CI - 0.09, - 0.05; p 0.1). Higher compared to lower doses of norepinephrine did not lead to a significant increase in adverse events in our practice (p > 0.1). We identified that mobilisation was safe with up to 0.20 mu g/kg/min norepinephrine for out-of-bed (IMS >= 2) and 0.33 mu g/kg/min for in-bed (IMS 0-1) mobilisation. Conclusions: Mobilisation with norepinephrine can be done safely when considering the status of the patient and safety guidelines. We demonstrated that safe mobilisation was possible with norepinephrine doses up to 0.20 mu g/kg/min for out-of-bed (IMS >= 2) and 0.33 mu g/kg/min for in-bed (IMS 0-1) mobilisation