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Compartment models are a widely used class of models that are useful when considering the flow of objects, people, or energy between different labeled states, referred to as compartments. Classic examples include SIR models in epidemiology and many pharmacokinetic models used in pharmacology. These models are formulated as sets of coupled ordinary differential equations, but in recent years there has been increasing interest in generalizations involving fractional differential equations. The majority of such generalizations have been performed in an ad hoc manner by replacing integer order derivatives with fractional derivatives. Such an approach does allow for the incorporation of history effects into the models, but may be problematic in a number of ways, such as breaking conservation of matter. To overcome these problems we have developed a systematic approach for the inclusion of fractional derivatives into compartment models by deriving the deterministic governing equations from an underlying physical stochastic process. This derivation also reveals the connection between these fractional order models and age-structured models. Unlike the ad hoc addition of fractional derivatives, our approach ensures that the model remains physically reasonable at all times and provides for an easy interpretation of all the parameters in the model. Illustrative examples, drawn from epidemiology, pharmacokinetics, and in-host virus dynamics, are provided. [ABSTRACT FROM AUTHOR]

Compartment models have been used to describe the time evolution of a system undergoing reactions between populations in different compartments. The governing equations are a set of coupled ordinary differential equations. In recent years fractional order derivatives have been introduced in compartment models in an ad hoc way, replacing ordinary derivatives with fractional derivatives. This has been motivated by the utility of fractional derivatives in incorporating history effects, but the ad hoc inclusion can be problematic for flux balance. To overcome these problems we have derived fractional order compartment models from an underlying physical stochastic process. In general, our fractional compartment models differ from ad hoc fractional models and our derivation ensures that the fractional derivatives have a physical basis in our models. Some illustrative examples, drawn from epidemiology, pharmacokinetics, and in-host virus dynamics, are provided. [ABSTRACT FROM AUTHOR]

Marine nematodes, which play an important role in many ecosystems, include a number of apparently cosmopolitan taxa that exhibit broad biogeographic ranges even though there is no obvious dispersal phase in their lifecycle. In this study, standard taxonomic approaches to marine nematode identification in conjunction with multivariate statistical analysis of morphometric data were compared with molecular techniques. Specimens of the marine nematode Terschellingia longicaudata that had been identified by their morphological features were investigated from a range of localities (East and West Atlantic, Bahrain, Malaysia) and habitats (estuarine, intertidal, subtidal) using molecular approaches based on the amplification and sequencing of the small subunit ribosomal RNA (18S rRNA). The study revealed that the majority of the morphologically defined T. longicaudata specimens share a single 18S rRNA sequence and apparently belong to a single taxon distributed from the British Isles to Malaysia. In addition, 18S rRNA analysis also revealed two additional sequences. One of these sequences was found in both the British Isles and Mexico, the other was recorded only from British waters. Individuals collected in Bahrain and identified from their morphology as T. longicaudata had two highly divergent 18S rRNA sequences. Separate morphological and morphometric approaches to identification of specimens from the same sites that had been formalin-preserved did not support evidence of multiple genotypes revealed previously by molecular analysis. Current taxonomy based on morphological characters detected using light-microscopy may be unable to discriminate possible species complexes. Biodiversity of marine nematodes may often be underestimated due to the presence of morphologically cryptic species complexes. High-throughput techniques such as DNA barcoding would aid in species identification but may require thorough analysis of multiple nuclear and mitochondrial molecular markers. [ABSTRACT FROM AUTHOR]

Small metazoans such as marine nematodes are increasingly identified using both molecular and morphological techniques. Formalin is the preferred fixative for morphological analysis but specimens become unsuitable for molecular study due to formalin-induced modification of DNA. Nematodes fixed in ethanol work well for molecular studies but become unsuitable for taxonomy due to shrinkage. Here we show for the first time that formalin can be used as a short-term fixative (≤ 7 days) for marine nematodes, allowing both morphological and molecular work to be conducted on the same individual. No sequence ambiguities were detected in polymerase chain reaction (PCR) amplifications of 18S ribosomal DNA (rDNA) following short-term formalin preservation. [ABSTRACT FROM AUTHOR]

Despite a growing interest in interdisciplinary research, systematic ways of how to integrate data from different disciplines are still scarce. We argue that successful resource management relies on two key data sources: natural science data, which represents ecosystem structure and processes, and social science data, which describes people's perceptions and understanding. Both are vital, mutually complementing information sources that can underpin the development of feasible and effective policies and management interventions. To harvest the added value of combined knowledge, a uniform scaling system is needed. In this paper, we propose a standardized methodology to connect and explore different types of quantitative data from the natural and social sciences reflecting temporal trends in ecosystem quality. We demonstrate this methodology with different types of data such as fisheries stocks and mangrove cover on the one hand and community's perceptions on the other. The example data are collected from three United Nations Educational Scientific and Cultural Organization (UNESCO) Biosphere reserves and one marine park in Southeast Asia. To easily identify patterns of convergence or divergence among the datasets, we propose heat maps using colour codes and icons for language- and education-independent understandability. Finally, we discuss the limitations as well as potential implications for resource management and the accompanying communication strategies. This article is part of the theme issue 'Nurturing resilient marine ecosystems'. [ABSTRACT FROM AUTHOR]

The European Marine Board recently published a position paper on linking oceans and human health as a strategic research priority for Europe. With this position paper as a reference, the March 2014 Cornwall Oceans and Human Health Workshop brought together key scientists, policy makers, funders, business, and non governmental organisations from Europe and the US to review the recent interdisciplinary and cutting edge research in oceans and human health specifically the growing evidence of the impacts of oceans and seas on human health and wellbeing (and the effects of humans on the oceans). These impacts are a complex mixture of negative influences (e.g. from climate change and extreme weather to harmful algal blooms and chemical pollution) and beneficial factors (e.g. from natural products including seafood to marine renewable energy and wellbeing from interactions with coastal environments). Integrated approaches across disciplines, institutions, and nations in science and policy are needed to protect both the oceans and human health and wellbeing now and in the future. [ABSTRACT FROM AUTHOR]

To examine the effect of prior exercise on the postprandial lipid response to a high-carbohydrate meal in normal-weight (NW = BMI <25) and overweight (OW = BMI ≥25) women (age 18-25), 10 NW and 10 OW participants completed 2 conditions separated by 1 month. In the morning, the day after control (CT = no exercise) or exercise conditions (EX = 60 min cycling at 60% VO2peak), participants consumed a high-carbohydrate meal (80% CHO, 15% protein, 5% fat; 75 kJ/kg BM) followed by 6 hr of hourly blood sampling. Blood was analyzed for triglycerides (TG), blood glucose (BG), and insulin (IN). TG levels over the 6-hr period were lower in NW than OW (p = .021) and lower in EX than in CT (p = .006). Area under the curve (AUC) for TG was lower in NW than OW (p = .016) and EX than CT (p = .003). There were nonsignificant tendencies for reduced BG over time (p = .053) and AUC (p = .083), and IN AUC was lower in EX than in CT (p = .040) for both groups and lower in NW than in OW (p = .039). Prior exercise improved TG levels after a high-carbohydrate meal in both groups, and OW women demonstrated a greater postprandial lipemic response than NW regardless of condition. There were tendencies for improved glucose removal with prior exercise in NW vs. OW. Acute exercise can improve postprandial TG responses and might also improve postprandial BG and IN after a large meal in NW and OW young women. [ABSTRACT FROM AUTHOR]

Scientific investigations have progressively refined our understanding of the influence of the environment on human health, and the many adverse impacts that human activities exert on the environment, from the local to the planetary level. Nonetheless, throughout the modern public health era, health has been pursued as though our lives and lifestyles are disconnected from ecosystems and their component organisms. The inadequacy of the societal and public health response to obesity, health inequities, and especially global environmental and climate change now calls for an ecological approach which addresses human activity in all its social, economic and cultural complexity. The new approach must be integral to, and interactive, with the natural environment. We see the continuing failure to truly integrate human health and environmental impact analysis as deeply damaging, and we propose a new conceptual model, the ecosystems- enriched Drivers, Pressures, State, Exposure, Ejects, Actions or 'eDPSEEA' model, to address this shortcoming. The model recognizes convergence between the concept of ecosystems services which provides a human health and well-being slant to the value of ecosystems while equally emphasizing the health of the environment, and the growing calls for 'ecological public health' as a response to global environmental concerns now suffusing the discourse in public health. More revolution than evolution, ecological public health will demand new perspectives regarding the interconnections among society, the economy, the environment and our health and well-being. Success must be built on collaborations between the disparate scientific communities of the environmental sciences and public health as well as interactions with social scientists, economists and the legal profession. It will require outreach to political and other stakeholders including a currently largely disengaged general public. The need for an effective and robust science-policy interface has never been more pressing. Conceptual models can facilitate this by providing theoretical frameworks and supporting stakeholder engagement process simplifications for inherently complex situations involving environment and human health and well-being. They can be tools to think with, to engage, to communicate and to help navigate in a sea of complexity. We believe models such as eDPSEEA can help frame many of the issues which have become the challenges of the new public health era and can provide the essential platforms necessary for progress. [ABSTRACT FROM AUTHOR]

Background and context: Lung cancer is estimated to be the fifth most commonly diagnosed cancer and leading cause of cancer death in Australia, representing 9.2% of all new cancer cases (n = 138,321) diagnosed and 18.9% of all cancer deaths (n = 48,586). The 5-year survival rate for those with lung cancer is 16%, compared with 68% for all cancers combined (between 2009 and 2013). Lung cancer is also the leading cause of cancer burden in Australia and patients affected by lung cancer may experience high levels of unmet need with associated psychological distress and decreased quality of life. Cancer Australia, Australia's national cancer control agency, developed the national Lung Cancer Framework: Principles for Best Practice Lung Cancer Care (Framework) to provide evidence-based, best practice information, strategies, tools and resources to support local adoption of the 5 principles for best practice management of lung cancer (principles): patient-centered care; multidisciplinary care; timely access to evidence-based care; coordination, communication and continuity of care; and data-driven improvements. Aim: The framework aims to improve the outcomes and experiences of people affected by lung cancer in Australia by supporting national uptake of the principles. Strategy/Tactics: Cancer Australia: • established a Lung Cancer Advisory Group to advise on strategies for national implementation of the framework and its principles • conducted a national lung cancer demonstration project, with advice from an Expert Steering Group, to demonstrate the delivery of lung cancer care according to the principles across a range of service delivery settings, and identify key factors contributing to ongoing delivery of best practice cancer care • completed systematic reviews for each principle to determine the effectiveness of the principles in improving lung cancer care processes and outcomes. Program/Policy process: To support national adoption of the framework and its principles, Cancer Australia: • developed a promotion and communication strategy for widespread national dissemination • convened a National Summit to bring together policy makers, clinical stakeholders and consumers to support local application of the principles, and drive optimal care for people affected by lung cancer • identified and communicated consumer, service, and system-level approaches to aid sustainable use of the principles. Outcomes: The evidence-based approach to the development of the framework and its principles identified ways to improve the healthcare system to achieve better outcomes for those affected by lung cancer in Australia. A coordinated approach to the delivery of the National Summit supported those involved in lung cancer care to share and adopt innovative and multilevel strategies for best practice care. What was learned: Embedding strategies to support implementation of the principles, responsive to local context, was key to enabling sustainable improvements in national lung cancer control. [ABSTRACT FROM AUTHOR]