Equilibrium in a two-agent assignment problem

In this paper we address a particular generalisation of the Assignment Problem (AP) in a Multi-Agent setting, where distributed agents share common resources. We consider the problem of determining Pareto-optimal solutions that satisfy a fairness criterion (equilibrium). We show that the solution obtained is equivalent to a Kalai Smorodinsky solution of a suitably defined bargaining problem and characterise the computational complexity of finding such an equilibrium. Additionally, we propose an exact solution algorithm based on a branch-and-bound scheme that exploits bounds obtained by suitably rounding the solutions of the corresponding linear relaxation, and give the results of extensive computational experiments. Copyright © 2009, Inderscience Publishers

Methods for conducting international Delphi surveys to optimise global participation in core outcome set development: a case study in gastric cancer informed by a comprehensive literature review

Copyright © 2021, The Author(s) Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.Background: Core outcome sets (COS) should be relevant to key stakeholders and widely applicable and usable. Ideally, they are developed for international use to allow optimal data synthesis from trials. Electronic Delphi surveys are commonly used to facilitate global participation; however, this has limitations. It is common for these surveys to be conducted in a single language potentially excluding those not fluent in that tongue. The aim of this study is to summarise current approaches for optimising international participation in Delphi studies and make recommendations for future practice. Methods: A comprehensive literature review of current approaches to translating Delphi surveys for COS development was undertaken. A standardised methodology adapted from international guidance derived from 12 major sets of translation guidelines in the field of outcome reporting was developed. As a case study, this was applied to a COS project for surgical trials in gastric cancer to translate a Delphi survey into 7 target languages from regions active in gastric cancer research. Results: Three hundred thirty-two abstracts were screened and four studies addressing COS development in rheumatoid and osteoarthritis, vascular malformations and polypharmacy were eligible for inclusion. There was wide variation in methodological approaches to translation, including the number of forward translations, the inclusion of back translation, the employment of cognitive debriefing and how discrepancies and disagreements were handled. Important considerations were identified during the development of the gastric cancer survey including establishing translation groups, timelines, understanding financial implications, strategies to maximise recruitment and regulatory approvals. The methodological approach to translating the Delphi surveys was easily reproducible by local collaborators and resulted in an additional 637 participants to the 315 recruited to complete the source language survey. Ninety-nine per cent of patients and 97% of healthcare professionals from non-English-speaking regions used translated surveys. Conclusion: Consideration of the issues described will improve planning by other COS developers and can be used to widen international participation from both patients and healthcare professionals.This study is funded by the National Institute for Health Research (NIHR) Doctoral Research Fellowship Grant (DRF-2015-08-023). JMB is partially funded by the NIHR Bristol Biomedical Research Centre and the MRC ConDUCT-II Hub for Trials Methodology Research. PRW was funded by the MRC North West Hub for Trials Methodology Research (Grant ref: MR/K025635/01).info:eu-repo/semantics/publishedVersio

Current management of the gastrointestinal complications of systemic sclerosis.

Systemic sclerosis is a multisystem autoimmune disorder that involves the gastrointestinal tract in more than 90% of patients. This involvement can extend from the mouth to the anus, with the oesophagus and anorectum most frequently affected. Gut complications result in a plethora of presentations that impair oral intake and faecal continence and, consequently, have an adverse effect on patient quality of life, resulting in referral to gastroenterologists. The cornerstones of gastrointestinal symptom management are to optimize symptom relief and monitor for complications, in particular anaemia and malabsorption. Early intervention in patients who develop these complications is critical to minimize disease progression and improve prognosis. In the future, enhanced therapeutic strategies should be developed, based on an ever-improving understanding of the intestinal pathophysiology of systemic sclerosis. This Review describes the most commonly occurring clinical scenarios of gastrointestinal involvement in patients with systemic sclerosis as they present to the gastroenterologist, with recommendations for the suggested assessment protocol and therapy in each situation

Modelling human travel patterns to evaluate intervention strategies for mosquito-borne disease

The aim of this paper is to evaluate the effectiveness of control strategies for diseases transmitted by the Aedes albopictus mosquito (the “Asian tiger”) and spread by human travel. This mosquito, which has become established in southern Europe in recent years, is a vector for many diseases. For example, an outbreak of chikungunya, hitherto regarded as a tropical disease, occurred in Italy in 2007. The initial case was a person who had acquired the disease overseas. Mosquito-borne infections can only be spread over large distances by human travel, as the flight range of mosquitos is very limited. A system dynamics model has been developed which describes the mosquito life-cycle, the natural history of mosquito-borne disease in humans and mosquitos, and human behaviour including travel. Potential disease control strategies include chemical treatments to destroy either larvae or adult mosquitos, campaigns to influence human behaviour, or quarantine of infectious people. In this paper, which is based on the Italian chikungunya outbreak, this model is used to study and compare the effect of different control strategies, where the various actions are combined in different ways and implemented for different time period

System dynamics models to assess the risk of mosquito-borne diseases and to evaluate control policies

This paper describes the development of a System Dynamics model to study the diffusion and control of disease transmitted by the mosquito Aedes albopictus in Italy. This insect is one of the world’s most invasive species, due to the global trade in used tyres, an efficient means of transport of mosquito eggs because they frequently contain small deposits of water. Ae. albopictus is very adaptable to climate change and is spreading rapidly into temperate zones. An outbreak of the “tropical” disease Chikungunya in Italy in 2007 proved that Europe is definitely at risk for Aedes-borne diseases. Although the work described in this paper concerns an application in Italy, it can be adapted to tackle other mosquito-borne diseases in other European countrie