A game-theoretic optimisation approach to fair customer allocation in oligopolies

Under the ever-increasing capital intensive environment that contemporary process industries face, oligopolies begin to form in mature markets where a small number of companies regulate and serve the customer base. Strategic and operational decisions are highly dependent on the firms’ customer portfolio and conventional modelling approaches neglect the rational behaviour of the decision makers, with regards to the problem of customer allocation, by assuming either static competition or a leader-follower structure. In this article, we address the fair customer allocation within oligopolies by employing the Nash bargaining approach. The overall problem is formulated as mixed integer program with linear constraints and a nonlinear objective function which is further linearised following a separable programming approach. Case studies from the industrial liquid market highlight the importance and benefits of the proposed game theoretic approach

Integrated production and inventory routing planning of oxygen supply chains

In this work, we address a production and inventory routing problem for a liquid oxygen supply chain comprising production facilities, distribution network, and distribution resources. The key decisions of the problem involve production levels of production plants, delivery schedule and routing through heterogeneous vehicles, and inventory strategies for national stock-out prevention. Due to the problem complexity, we propose a two-level hybrid solution approach that solves the problem using both exact and metaheuristic methods. At the upper level, we develop a mixed-integer linear programming (MILP) model that determines production and inventory decisions and customer allocation. In the lower level, the original problem is reduced to several multi-trip heterogeneous vehicle routing problems by fixing the optimal production, inventory, and allocation decisions and clustering customers. A well-recognised metaheuristic, guided local search method, is adapted to solve the low-level routing problems. A real-world case study in the UK illustrates the applicability and effectiveness of the proposed optimisation framework

ICI 182,780 has agonistic effects and synergizes with estradiol-17 beta in fish liver, but not in testis

BACKGROUND: ICI 182,780 (ICI) belongs to a new class of antiestrogens developed to be pure estrogen antagonists and, in addition to its therapeutic use, it has been used to knock-out estrogen and estrogen receptor (ER) actions in several mammalian species. In the present study, the effects and mechanism of action of ICI were investigated in the teleost fish, sea bream (Sparus auratus). METHODS: Three independent in vivo experiments were performed in which mature male tilapia (Oreochromis mossambicus) or sea bream received intra-peritoneal implants containing estradiol-17 beta (E2), ICI or a combination of both compounds. The effects of E2 and ICI on plasma calcium levels were measured and hepatic and testicular gene expression of the three ER subtypes, ER alpha, ER beta a and ER beta b, and the estrogen-responsive genes, vitellogenin II and choriogenin L, were analyzed by semi-quantitative RT-PCR in sea bream. RESULTS: E2 treatment caused an increase in calcium levels in tilapia, while ICI alone had no noticeable effect, as expected. However, pretreatment with ICI synergistically potentiated the effect of E2 on plasma calcium in both species. ICI mimicked some E2 actions in gene expression in sea bream liver upregulating ER alpha, vitellogenin II and choriogenin L, although, unlike E2, it did not downregulate ER beta a and ER beta b. In contrast, no effects of E2 or ICI alone were detected in the expression of ERs in testis, while vitellogenin II and choriogenin L were upregulated by E2 but not ICI. Finally, pretreatment with ICI had a synergistic effect on the hepatic E2 down-regulation of ER beta b, but apparently blocked the ER alpha up-regulation by E2. CONCLUSION: These results demonstrate that ICI has agonistic effects on several typical estrogenic responses in fish, but its actions are tissue-specific. The mechanisms for the ICI agonistic activity are still unknown; although the ICI induced up-regulation of ER alpha mRNA could be one of the factors contributing to the cellular response

Coffee certification in Brazil: compliance with social standards and its implications for social equity

© 2018, The Author(s). This paper addresses the relationship between compliance with social performance criteria (the social outcomes that must be achieved for certification) and procedural (management) criteria and this relationship’s significance for social equity at both farm and wider landscape levels. We consider social performance compliance to be pertinent to farm-level equity, and the relative compliance of small versus large farms to be pertinent to landscape-level equity. Certification’s management requirements are often deemed disproportionately burdensome for small, resource-poor producers, and hence a barrier to landscape-level equity. There is a lack of research examining how management criteria impact the ability of different sized farms to meet certification’s social performance requirements. We analysed 435 certification audits, covering all Brazilian coffee farms that sought Rainforest Alliance certification from 2006 to 2014 inclusive: 80 individual farms and 23 groups of farms. In principle, undergoing group certification permits smallholders to benefit from economies of scale. Our analysis revealed a statistically significant, positive correlation between compliance with procedural (managing sustainability plans) and social performance criteria. This correlation was stronger for groups than individual farms. Group farms’ compliance was statistically equivalent to that of individual farms, suggesting that group certification is achieving its intended purpose of socio-economic levelling of certified farmers. Over time, certified farms’ average compliances improved. Our findings suggest that management requirements play an important role in improving smallholders’ overall social sustainability performance and that group certification may help resource-poor smallholders achieve those requirements. Further work is required to understand causal mechanisms underlying the relationships we present

Multi analyte profiling and variability of inflammatory markers in blood and induced sputum in patients with stable COPD

<p>Abstract</p> <p>Background</p> <p>We analyzed serial concentrations of multiple inflammatory mediators from serum and induced sputum obtained from patients with stable COPD and controls. The objective was to determine which proteins could be used as reliable biomarkers to assess COPD disease state and severity.</p> <p>Methods</p> <p>Forty-two subjects; 21 with stable COPD and 21 controls, were studied every 2 weeks over a 6-week period. Serum and induced sputum were obtained at each of 3 visits and concentrations of 19 serum and 22 sputum proteins were serially assessed using multiplex immunoassays. We used linear mixed effects models to test the distribution of proteins for an association with COPD and disease severity. Measures of within- and between-subject coefficients of variation were calculated for each of the proteins to assess reliability of measurement.</p> <p>Results</p> <p>There was significant variability in concentrations of all inflammatory proteins over time, and variability was greater for sputum proteins (median intra-subject coefficient of variation 0.58) compared to proteins measured in serum (median intra-subject coefficient of variation 0.32, P = 0.03). Of 19 serum proteins and 22 sputum proteins tested, only serum CRP, myeloperoxidase and VEGF and sputum IL-6, IL-8, TIMP-1, and VEGF showed acceptable intra and inter-patient reliability and were significantly associated with COPD, the severity of lung function impairment, and dyspnea.</p> <p>Conclusions</p> <p>Levels of many serum and sputum biomarkers cannot be reliably ascertained based on single measurements. Multiple measurements over time can give a more reliable and precise estimate of the inflammatory burden in clinically stable COPD patients.</p

Management of the Sickle Cell Trait: An Opinion by Expert Panel Members.

The number of individuals with the sickle cell trait exceeds 300 million worldwide, making sickle cell disease one of the most common monogenetic diseases globally. Because of the high frequency of sickle cell disease, reproductive counseling is of crucial importance. In addition, unlike other carrier states, Sickle Cell Trait (SCT) seems to be a risk factor for several clinical complications, such as extreme exertional injury, chronic kidney disease, and complications during pregnancy and surgery. This expert panel believes that increasing knowledge about these clinical manifestations and their prevention and management can be a useful tool for all healthcare providers involved in this issue

Morbidity and mortality of sickle cell disease patients is unaffected by splenectomy: evidence from three decades of follow-up in a high-income setting

Sickle cell disease (SCD) is a globally widespread hereditary red cell disorder characterized by the production of pathological hemoglobin S (HbS).1 Patients with SCD include homozygous subjects for HbS (SS) and compound heterozygotes with HbS/HbC (SC) or HbS/β+/0-thalassemia (Sβ0/β+). In Italy, SCD is endemic with HbS/β+/0-thalassemia being prevalent in areas of southern Italy. In the last two decades, the number of SCD patients across Italy has increased due to migration from sub-Saharan Africa and th

House-level risk factors for triatomine infestation in Colombia.

BACKGROUND: Chagas disease, transmitted domestically by triatomine bugs, is the most important vector-borne disease in Latin America. The association between triatomine infestation and housing characteristics was investigated based on a standardized survey in 41 971 houses in 15 Departments in Colombia. METHODS: Multivariate logistic regression was used to test for associations of two highly correlated infestation measures of infestation (householders reporting having seen triatomines inside the house, and sending triatomines to the survey team), with 15 household-level risk factors. Risks were measured relative to a reference category of houses with up to three inhabitants, area up to 50 m(2), unplastered adobe walls, thatch roof and no outbuildings or domestic animals. RESULTS: The probability of seeing triatomines was highest for households with over seven inhabitants (OR = 1.24, 95% CI 1.11-1.39), overhead storage space (OR = 1.16, 95% CI 1.03-1.32), grain shed (OR = 1.25, 95% CI 1.02-1.52), cats (OR = 1.27, 95% CI 1.14-1.42) and pigs (OR = 1.16, 95% CI 1.03-1.30). Lowest risks were in houses with wooden walls (OR = 0.46, 95% CI 0.34-0.61), fully plastered walls (OR = 0.78, 95% CI 0.68-0.88), roofs made of tiles (OR = 0.51, 95% CI 0.33-0.78) and flagstone floors (OR = 0.57, 95% CI 0.42-0.76). Results for householders returning triatomines support this set of risk factors, but with wider confidence intervals. CONCLUSIONS: Surveillance of a few easily assessed household characteristics provides an accurate, rapid assessment of house-level variation in risk. Measured effect sizes for specific structural characteristics could be used to maximize the cost-effectiveness of programmes to reduce vector infestation and interrupt Chagas disease transmission by improving house quality

The Association Between Self-Reported Symptoms of Recent Airway Infection and CRP Values in a General Population: The Tromsø Study: Tromsø 6

C-reactive protein (CRP) is a much used biomarker for respiratory tract infection; however, the influence of airway infection on the CRP level in the general population has not been well described. The study aimed to evaluate the impact of recent symptoms of airway infection on the CRP level and how the predictive power of other known CRP predictors is influenced by taking respiratory symptoms into account. A total of 6,325 participants, aged 38–87 years, in the Tromsø Study, a repeated population-based survey, were examined with questionnaires, measurements of height and weight, spirometry, and high-sensitivity CRP analyses. The mean CRP value was 2.86 mg/L, and the geometric mean was 1.51 mg/L. Geometric means above 2.0 mg/L were found in the subgroups with the following characteristics: self-reported COPD, diabetes, recent symptoms of airway infection, forced expiratory volume in 1 s (FEV1) <80% predicted, body mass index (BMI) ≥30, and subjects treated with inhaled or oral corticosteroids. Among the subjects who reported recent airway infection, 10.5% had a CRP value of ≥10 mg/L, compared to 3.3% among the remaining participants. By multivariate analysis, BMI was the strongest independent predictor of the CRP level, followed by recent airway infection, FEV1% predicted, age, and current smoking. The study clearly demonstrates that a report of recent symptoms of airway infection strongly predicts the CRP level in the population. Such symptoms were shared rather equally between subgroups with increased CRP level, and the risk of being an important confounder in epidemiological studies is probably low. In the clinical setting, care should be taken when using the CRP level as a guide for medical prevention of chronic diseases