Efficacy of UVC-treated, pathogen-reduced platelets versus untreated platelets: a randomized controlled non-inferiority trial

Pathogen reduction (PR) technologies for blood components have been established to reduce the residual risk of known and emerging infectious agents. THERAFLEX UVPlatelets, a novel UVC light-based PR technology for platelet concentrates, works without photoactive substances. This randomized, controlled, double-blind, multicenter, noninferiority trial was designed to compare the efficacy and safety of UVC-treated platelets to that of untreated platelets in thrombocytopenic patients with hematologic-oncologic diseases. Primary objective was to determine non-inferiority of UVC-treated platelets, assessed by the 1-hour corrected count increment (CCI) in up to eight per-protocol platelet transfusion episodes. Analysis of the 171 eligible patients showed that the defined non-inferiority margin of 30% of UVC-treated platelets was narrowly missed as the mean differences in 1-hour CCI between standard platelets versus UVC-treated platelets for intention-to-treat and perprotocol analyses were 18.2% (95% confidence interval [CI]: 6.4%; 30.1) and 18.7% (95% CI: 6.3%; 31.1%), respectively. In comparison to the control, the UVC group had a 19.2% lower mean 24-hour CCI and was treated with an about 25% higher number of platelet units, but the average number of days to next platelet transfusion did not differ significantly between both treatment groups. The frequency of low-grade adverse events was slightly higher in the UVC group and the frequencies of refractoriness to platelet transfusion, platelet alloimmunization, severe bleeding events, and red blood cell transfusions were comparable between groups. Our study suggests that transfusion of pathogen-reduced platelets produced with the UVC technology is safe but non-inferiority was not demonstrated. (The German Clinical Trials Register number: DRKS00011156)

Experience with a framework for developing heuristics for solving rich vehicle routing problems

According to Cordeau et al. (J Oper Res Soc 53(5):512-522, 2002) a good VRP heuristic should fulfill four criteria: accuracy, speed, simplicity, and flexibility. In this paper we report experience with a heuristic framework for solving rich vehicle routing problems (RVRP), which is based on rather simple heuristics. This heuristic framework has been implemented as flexible software framework. The user-friendly design enables flexible customization of problem-specific solvers. Our computational study on five RVRP reveals that the heuristic approach is rather robust with respect to parameterization and that the solvers which have been customized from the framework can compete with state-of-the-art special purpose developments

A computational study comparing different multiple neighbourhood strategies for solving rich vehicle routing problems

In this paper we report the results of an extensive computational study on a variety of rich vehicle routing problems in which two fundamentally different paradigms or strategies of applying (the same set of) different neighbourhoods are assessed with respect to effectivity (solution quality) and efficiency (speed). We especially compare the structured approach known from variable neighbourhood search where neighbourhoods are applied in some fixed sequential order with an approach where neighbourhoods are applied concurrently. Since all approaches are implemented using the same basic modules, differences can be attributed to this strategic difference. We can show that, first, the application of large neighbourhoods is essential for quality, and, second, that the concurrent strategy outperforms the sequential strategy

Solving Multitrip Vehicle Routing Under Order Incompatibilities: A VRP Arising in Supply Chain Management

In this study, we introduce a new class of vehicle routing problems (VRP): the multidepot multitrip VRP with order incompatibilities. The problem is motivated by a specific two-echelon distribution system arising in supply chain management, where products come to the depots from different factories by semitrailers and these semitrailers are also used for short-haul distribution, that is, the load from different factories is not consolidated at the depots. This VRP is rather challenging as it combines several synchronisation constraints occurring in other well-known standard VRP. In this article, we describe several problem variants, we model the problem as a set partitioning problem, and we show how the heuristic concept of concurrent (LS/LNS) neighborhood search which has shown to be rather effective for other complex VRP-classes can be customized. Our computational study shows that this approach is effective and efficient for this VRP-class, too. (C) 2014 Wiley Periodicals, Inc

Review and analysis of current Shariah-compliant equity screening practice

Purpose – The purpose of this paper is to analyze the impact of applying alternative Shariah screens on the resulting universe of halal assets and to show that Shariah screening procedures currently used in practice are inconsistent with respect to discriminating between halal and haram. Design/methodology/approach – An empirical data analysis of the different asset universes obtained when applying the criteria specified by the most prominent Shariah-compliant funds and indexes to a common standard asset universe, the assets contained in the S&P 500 index. Findings – Analysis reveals that the asset universes are significantly different in size as well as constituents, i.e. for every index there is a substantial number of assets which are specified as halal or haram but classified the opposite way for other indexes. This indicates that, so far, there is no universal or generally accepted understanding of how to transform the descriptive Shariah rules into a system of checkable investment guidelines. Research limitations/implications – The results presented in this paper could motivate the development of a standardized screening framework which, taking into account the existing Shariah guidelines, produces a controlled, unified and understandable classification of assets, by which the credibility and consistency of Islamic equity products is enriched. Practical implications – Islamic institutions and Shariah scholars are guided to set up a common and standardized Shariah screening norm based on which computer-based management systems for Shariah compatible portfolios could be developed. Originality/value – This paper is believed to be the first empirical comparative analysis identifying the impact of using different Shariah screens on the composition of the compliant asset universe. The sensitization of Shariah scholars, fund managers and Islamic investors for the consequences of this so far undiscovered relation will certainly contribute to an enrichment of the credibility and consistency of Islamic equity products.Classification schemes, Equity capital, Financial management, Fund management, Islam

Solving a real-world vehicle routing problem with multiple use of tractors and trailers and EU-regulations for drivers arising in air cargo road feeder services

In this paper we present two approaches for solving a real-world vehicle routing problem arising in the air cargo road feeder service business. The problem is to combine transportation tasks from a given timetable to trips which have to be assigned to tractors and which can be operated by tractor drivers respecting the restrictive rules on driving times from EC Regulation No. 561/2006. Tractor trips which start and end at the hub can be combined to multiple-trips which are operated by the same tractor. Also, to each trip a trailer has to be assigned which is compatible with all tasks in the trip. The primary objective is to minimize the number of required tractors, i.e. the number of multiple-trips. The methods developed are currently applied in practice.Vehicle routing Air cargo services EU-regulation Multiple-trips

New strategies and a new paradigm for Shariah-compliant portfolio optimization

In this paper we analyze the effects of different strategies to construct Shariah compatible financial portfolios. The difference between conventional and current Shariah portfolio management is the application of sector screens and financial screens by which the asset universe is reduced. Yet, here different schools of scholars define different screening rules leading to significant differences with respect to compliance, but also with respect to performance. After analyzing this discrepancy we propose several new strategies to apply the inconsistent rule systems and a new paradigm for defining Shariah-compliance. Under this new paradigm compliance is attributed to the portfolio and not to the individual assets of the universe. We report results of an empirical study analyzing the potentials of these strategies and of the paradigm. We can show that under the proposed concepts Shariah-compliant portfolios can be realized which have return and risk profiles comparable to the conventional non-constrained portfolios.Shariah guidelines Islamic funds Portfolio models Empirical analysis