The management of segmental tibial shaft fractures: A systematic review.

INTRODUCTION: Segmental tibial fractures are complex injuries associated with significant soft tissue damage that are difficult to treat. This study aimed to identify the most effective method of treating segmental tibial fractures. METHOD: A PRISMA compliant systematic review was conducted. Studies investigating the management of segmental tibial fractures with intramedullary nail fixation (IMN), open reduction and internal fixation (ORIF) or circular external fixation (CEF) were included for review. The primary outcome measure was time to fracture union. Secondary outcomes were complications and functional outcome. A narrative analysis was undertaken as meta-analysis was inappropriate due to heterogeneity of the data. RESULTS: Thirteen studies were eligible and included. No randomised controlled trials were identified. Fixation with an intramedullary nail provided the fastest time to union, followed by open reduction and internal fixation and then CEF. The rate of deep infection was highest after IMN (5/162 [3%]), followed by open reduction and internal fixation (2/78 [2.5%]) and CEF (1/54 [2%]). However, some studies reported particularly high rates of infection following IMN for open segmental tibial fractures. There was limited reporting of postoperative deformities. From the studies that did include such data, there was a higher rate of deformity following ORIF (8/53 [15%]), compared to IMN (13/138 [9%]), and CEF (4/44 [9%]). Three studies, not including IMN, described patient reported outcome measures with results ranging from 'excellent' to 'fair'. DISCUSSION: The available evidence was of poor quality, dominated by retrospective case series. This prevented statistical analysis, and precludes firm conclusions being drawn from the results available. CONCLUSION: IMN has the fastest time to fracture union, however there are concerns regarding an increased deep infection rate in open segmental tibial fractures. In this subgroup, the data suggests CEF provides the most satisfactory results. However, the available literature does not provide sufficient detail to make this statement with certainty. We recommend a randomised controlled study to further investigate this challenging problem

Decoupling of morphological disparity and taxic diversity during the adaptive radiation of anomodont therapsids

Adaptive radiations are central to macroevolutionary theory. Whether triggered by acquisition of new traits or ecological opportunities arising from mass extinctions, it is debated whether adaptive radiations are marked by initial expansion of taxic diversity or of morphological disparity (the range of anatomical form). If a group rediversifies following a mass extinction, it is said to have passed through a macroevolutionary bottleneck, and the loss of taxic or phylogenetic diversity may limit the amount of morphological novelty that it can subsequently generate. Anomodont therapsids, a diverse clade of Permian and Triassic herbivorous tetrapods, passed through a bottleneck during the end-Permian mass extinction. Their taxic diversity increased during the Permian, declined significantly at the Permo–Triassic boundary and rebounded during the Middle Triassic before the clade's final extinction at the end of the Triassic. By sharp contrast, disparity declined steadily during most of anomodont history. Our results highlight three main aspects of adaptive radiations: (i) diversity and disparity are generally decoupled; (ii) models of radiations following mass extinctions may differ from those triggered by other causes (e.g. trait acquisition); and (iii) the bottleneck caused by a mass extinction means that a clade can emerge lacking its original potential for generating morphological variety

A bibliometric analysis assessing temporal changes in publication and authorship characteristics in The Knee from 1996 to 2016.

BACKGROUND: Evidence-based practice is a foundation to clinical excellence. However there remains little evidence on the characteristics of authors who contribute to the evidence-base and whether these have changed over time. The purpose of this study was to explore these characteristics by undertaking a bibliometric analysis to explore publication and authorship characteristics in a leading sub-speciality orthopaedic journal (The Knee) over a 20-year period. METHODS: All articles published in The Knee in 1996, 2006 and 2016 were identified. For each article, data collected included: highest academic award; profession; gender; continent of first and last author; total number of authors; the level of evidence; and funding source. We analysed temporal changes in these variables using appropriate statistical models. RESULTS: A total of 413 papers were analysed. Between 1996 to 2016 there has been a significant increase in the overall number of authors, the number of paper submitted from Asia, the proportion of Level 1 or 2 tiered evidence, the proportion of people with Bachelor or Master-level degrees as their highest level of educational award and the proportion of non-medically qualified authors (P<0.001). From 2006 to 2016 there was a significant increase in the proportion of articles whose first author was female (P=0.03), but no significant change in the number of females as last author (P=0.43). CONCLUSION: The findings indicate that there have been changes in publication and authorship characteristics in this sub-speciality orthopaedic journal during the past 20years. This provides encouraging indication of greater diversification and internationalisation of orthopaedic research

Duration of shedding of respiratory syncytial virus in a community study of Kenyan children

Background: Our understanding of the transmission dynamics of respiratory syncytial virus (RSV) infection will be better informed with improved data on the patterns of shedding in cases not limited only to hospital admissions. Methods: In a household study, children testing RSV positive by direct immunofluorescent antibody test (DFA) were enrolled. Nasal washings were scheduled right away, then every three days until day 14, every 7 days until day 28 and every 2 weeks until a maximum of 16 weeks, or until the first DFA negative RSV specimen. The relationship between host factors, illness severity and viral shedding was investigated using Cox regression methods. Results: From 151 families a total of 193 children were enrolled with a median age of 21 months (range 1-164 months), 10% infants and 46% male. The rate of recovery from infection was 0.22/person/day (95% CI 0.19-0.25) equivalent to a mean duration of shedding of 4.5 days (95%CI 4.0-5.3), with a median duration of shedding of 4 days (IQR 2-6, range 1-14). Children with a history of RSV infection had a 40% increased rate of recovery i.e. shorter duration of viral shedding (hazard ratio 1.4, 95% CI 1.01-1.86). The rate of cessation of shedding did not differ significantly between males and females, by severity of infection or by age. Conclusion: We provide evidence of a relationship between the duration of shedding and history of infection, which may have a bearing on the relative role of primary versus re-infections in RSV transmission in the community

Stable isotope evidence for crustal recycling as recorded by superdeep diamonds

© 2015 Elsevier B.V. Sub-lithospheric diamonds from the Juina-5 and Collier-4 kimberlites and the Machado River alluvial deposit in Brazil have carbon isotopic compositions that co-vary with the oxygen isotopic compositions of their inclusions, which implies that they formed by a mixing process. The proposed model for this mixing process, based on interaction of slab-derived carbonate melt with reduced (carbide- or metal-bearing) ambient mantle, explains these isotopic observations. It is also consistent with the observed trace element chemistries of diamond inclusions from these localities and with the experimental phase relations of carbonated subducted crust. The 18O-enriched nature of the inclusions demonstrates that they incorporate material from crustal protoliths that previously interacted with seawater, thus confirming the subduction-related origin of superdeep diamonds. These samples also provide direct evidence of an isotopically anomalous reservoir in the deep (≥350 km) mantle

Invited Review: IPCC, Agriculture and Food - A Case of Shifting Cultivation and History.

Since 1990 the Intergovernmental Panel on Climate Change (IPCC) has produced five Assessment Reports (ARs), in which agriculture as the production of food for humans via crops and livestock have featured in one form or another. A constructed data base of the ca. 2,100 cited experiments and simulations in the five ARs were analysed with respect to impacts on yields via crop type, region and whether or not adaptation was included. Quantitative data on impacts and adaptation in livestock farming have been extremely scarce in the ARs. The main conclusions from impact and adaptation are that crop yields will decline but that responses have large statistical variation. Mitigation assessments in the ARs have used both bottom-up and top-down methods but need better to link emissions and their mitigation with food production and security. Relevant policy options have become broader in later ARs and included more of the social and non-production aspects of food security. Our overall conclusion is that agriculture and food security, which are two of the most central, critical and imminent issues in climate change, have been dealt with in an unfocussed and inconsistent manner between the IPCC five ARs. This is partly a result of agriculture spanning two IPCC working groups but also the very strong focus on projections from computer crop simulation modelling. For the future, we suggest a need to examine interactions between themes such as crop resource use efficiencies and to include all production and non-production aspects of food security in future roles for integrated assessment models

Seeking the Real Adam Smith and Milton Friedman

In this paper we will analyze the relationship between free market principles and ethics through an exploration of how too many business managers often approach the ideas of Adam Smith and Milton Friedman. In doing so, we aim to provide a thoughtful foundation for future discussions of how we ought to navigate this intersection. We briefly examine questions such as: What is the relationship between the “best” economy in terms of efficiency and the common good for society? Is pursuing one’s individual economic advantage the same as promoting the general interest? As we analyze and discuss these questions, specifically in the context of Smith and Friedman, we also make some alternative normative assertions, grounded in social welfare, about adopting a broader societal perspective for the purpose of business

Regularity of solutions to higher-order integrals of the calculus of variations

We obtain new regularity conditions for problems of calculus of variations with higher-order derivatives. As a corollary, we get non-occurrence of the Lavrentiev phenomenon. Our main regularity result asserts that autonomous integral functionals with a Lagrangian having coercive partial derivatives with respect to the higher-order derivatives admit only minimizers with essentially bounded derivatives