Long subcutaneous tunnelling reduces infection rates in paediatric external ventricular drains

Purpose The aim of this study is to report the efficacy of long subcutaneous tunnelling of external ventricular drains in reducing rates of infection and catheter displacement in a paediatric population. Methods In children requiring external ventricular drainage, a long-tunnelled drain was placed and managed according to a locally agreed guideline. End points were novel CSF infection incurred during the time of drainage and re-operation to re-site displaced catheters. Data were compared to other published series. Results One hundred eighty-one long-tunnelled external ventricular drains (LTEVDs) were inserted. The mean age was 6.6 years (range 0-15.5 years). Reasons for insertion included intraventricular haemorrhage (47 %), infection (27 %), tumour-related hydrocephalus (7.2 %), as a temporising measure (17 %) and trauma (2.2 %). The overall new infection rate for LTEVD was 2.76 %. If the 48 cases where LTEVDs were inserted to treat an existing infection are excluded, the infection rate was 3.8 % (5/133). The mean duration of insertion was 10 days (range 0-42 days). Four LTEVDs (2.2 %) were inadvertently dislodged, requiring reinsertion. Thirteen patients required removal of EVD alone.There was a significant difference (p < 0.05) when comparing our infection rate to 14 publications of infection rates in short-tunnelled EVDs; however, there was no difference when comparing our data to three publications using LTEVDs. Conclusion The use of an antibiotic-impregnated LTEVD, managed according to a predefined guideline, is associated with significantly reduced infection and displacement rates when compared with contemporary series. It is suggested that this reduction is of both clinical and economic benefits

An Axiomatic Analysis of Diversity Evaluation Metrics: Introducing the Rank-Biased Utility Metric

Many evaluation metrics have been defined to evaluate the effectiveness ad-hoc retrieval and search result diversification systems. However, it is often unclear which evaluation metric should be used to analyze the performance of retrieval systems given a specific task. Axiomatic analysis is an informative mechanism to understand the fundamentals of metrics and their suitability for particular scenarios. In this paper, we define a constraint-based axiomatic framework to study the suitability of existing metrics in search result diversification scenarios. The analysis informed the definition of Rank-Biased Utility (RBU) -- an adaptation of the well-known Rank-Biased Precision metric -- that takes into account redundancy and the user effort associated to the inspection of documents in the ranking. Our experiments over standard diversity evaluation campaigns show that the proposed metric captures quality criteria reflected by different metrics, being suitable in the absence of knowledge about particular features of the scenario under study.Comment: Original version: 10 pages. Preprint of full paper to appear at SIGIR'18: The 41st International ACM SIGIR Conference on Research & Development in Information Retrieval, July 8-12, 2018, Ann Arbor, MI, USA. ACM, New York, NY, US

Independent evolution of sexual dimorphism and female-limited mimicry in swallowtail butterflies (Papilio dardanus and Papilio phorcas)

Several species of Swallowtail butterflies (genus Papilio) are Batesian mimics that express multiple mimetic female forms, while the males are monomorphic and non-mimetic. The evolution of such sex-limited mimicry may involve sexual dimorphism arising first and mimicry subsequently. Such a stepwise scenario through a non-mimetic, sexually dimorphic stage has been proposed for two closely related sexually dimorphic species; P. phorcas, a non-mimetic species with two female forms, and P. dardanus, a female-limited polymorphic mimetic species. Their close relationship indicates that female-limited polymorphism could be a shared derived character of the two species. Here we present a phylogenomic analysis of the dardanus group using 3964 nuclear loci and whole mitochondrial genomes showing that they are not sister species, and thus that the sexually-dimorphic state has arisen independently in the two species. Non-homology of the female polymorphism in both species is supported by population genetic analysis of engrailed, the presumed mimicry switch locus in P. dardanus. McDonald-Kreitman tests performed on SNPs in engrailed showed the signature of balancing selection in a polymorphic population of P. dardanus, but not in monomorphic populations, nor in the non-mimetic P. phorcas. Hence the wing polymorphism does not balance polymorphisms in engrailed in P. phorcas. Equally, unlike in P. dardanus, none of the SNPs in P. phorcas engrailed were associated with either female morph. We conclude that sexual dimorphism due to female polymorphism evolved independently in both species from monomorphic, non-mimetic states. While sexual selection may drive male-female dimorphism in non-mimetic species, in mimetic Papilios natural selection for protection from predators in females is an alternative route to sexual dimorphism

Materials Classification Using Multichannel Radiographs

This work aims to validate previous exploratory work done to characterize materials by matching their attenuation profiles using a multichannel radiograph given an initial energy spectrum. The experiment was performed in order to evaluate the effects of noise on the resulting attenuation profiles, which was ignored in simulation. Spectrum measurements have also been collected from various materials of interest. Additionally, a MATLAB optimization algorithm has been applied to these candidate spectrum measurements in order to extract an estimate of the attenuation profile. Being able to characterize materials through this nondestructive method has an extensive range of applications for national security

Take a walk on the wild side: Exploring, identifying, and developing consultancy expertise with elite performance team leaders

Objectives: Stemming from sport psychology’s recent shift to examine the effective management of elite sports team organizations, the extensive, significant, and complex challenges faced by those with responsibility for team performance have been emphasized. Recognizing that most work in this budding area has been theoretical in nature, our contribution to this special issue consequently identifies and critically evaluates some implications for excellence in practitioners who support leaders of elite sport performance teams. Method: Narrative review and commentary. Results and Conclusions: To survive and succeed, leaders of elite teams must: (a) negotiate complex and contested socio-political dynamics both within and outside their performance department; (b) make impactful and consistent real-time decisions; and (c) continually reinforce and protect their programme. To provide an optimally impactful and valued service, sport psychologists must therefore be able to advise on a broad and politically-astute leadership style and, most critically for consultancy excellence: (a) work within a professional judgment and decision making model; (b) facilitate the leader’s adaptive expertise and nested decision making; and (c) operate a proactive, forthright, and straight approach to ethical considerations. Based on these implications, we conclude by providing suggestions for the training and development of applied consultants