3,303 research outputs found

    The interplay between habitat structure and chemical contaminants on biotic responses of benthic organisms

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    Habitat structure influences the diversity and distribution of organisms, potentially affecting their response to disturbances by either affecting their ‘susceptibility’ or through the provision of resources that can mitigate impacts of disturbances. Chemical disturbances due to contamination are associated with decreases in diversity and functioning of systems and are also likely to increase due to coastal urbanisation. Understanding how habitat structure interacts with contaminants is essential to predict and therefore manage such effects, minimising their consequences to marine systems. Here, we manipulated two structurally different habitats and exposed them to different types of contaminants. The effects of contamination and habitat structure interacted, affecting species richness. More complex experimental habitats were colonized by a greater diversity of organisms than the less complex habitats. These differences disappeared, however, when habitats were exposed to contaminants, suggesting that contaminants can override effects of habitats structure at small spatial scales. These results provide insight into the complex ways that habitat structure and contamination interact and the need to incorporate evidence of biotic responses from individual disturbances to multiple stressors. Such effects need to be taken into account when designing and planning management and conservation strategies to natural systems

    Can transplanting enhance mobile marine invertebrates in ecologically engineered rock pools?

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    © 2018 Elsevier Ltd The field of eco-engineering has burgeoned in recent years in response to the proliferation of artificial structures. Adding water-retaining features to seawalls has been successful in increasing biodiversity relative to the surrounding structure. Artificial rock pools may not, however, completely mimic natural rock pools. Here, we compared natural colonisation, through dispersal and recruitment, of intertidal mobile species to water-retaining flowerpots on seawalls with that into rock pools. This represents the more usual ‘passive’ approach to eco-engineering where features are built to enhance biodiversity and are allowed to colonise naturally, as opposed to seeding or transplanting organisms to features. While flowerpots supported some mobile species not found on the seawall, other species common on natural shores did not recruit to flowerpots. Thus, in a second experiment we tested the effectiveness of an ‘active’ approach through transplanting mobile organisms to flowerpots to expedite the colonisation process. For the species examined, however, most individuals did not stay in the flowerpots for more than 24 h after being transplanted. Further understanding of the processes (e.g. dispersal distances, recruitment) influencing colonisation of eco-engineered habitats is needed to effectively inform management of marine infrastructure, particularly for projects targeted at restoration rather than enhancement

    A Genetic Analysis of the Relationship Between Life-history Variation and Heat-shock Tolerance in Drosophila buzzatii

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    Although exposure to environmental stress is common in most populations, and the physiological effects of stress on individuals are well studied, the evolutionary importance of stress to populations is not well understood. To address multitrait responses to environmental change and potential constraints on character evolution, we analysed, in 100 isofemale lines of Drosophila buzzatii, the genetic relationships between resistance to a short heat shock and several life-history traits: survival in benign conditions, larval developmental time, fecundity and longevity. Estimates of heritability of larval thermotolerance were low, but significant, and all life-history traits varied significantly among isofemale lines. Several of these traits covaried significantly. Most correlations indicated positive life-history relationships, but males and females from lines where female fecundity was higher developed more slowly in the absence of stress, which is a negative life-history relationship. The stress reduced or negated many trait associations, and showed one additional relationship; more larvae from lines that developed fast at 25°C survived to adult after stress than did larvae from slow developing lines. These shifts in fitness relationships, when a single stress bout is applied, suggest that even small increases in environmental stress can have profound effects on evolutionary relationships among life-history traits

    A network-based dynamical ranking system for competitive sports

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    From the viewpoint of networks, a ranking system for players or teams in sports is equivalent to a centrality measure for sports networks, whereby a directed link represents the result of a single game. Previously proposed network-based ranking systems are derived from static networks, i.e., aggregation of the results of games over time. However, the score of a player (or team) fluctuates over time. Defeating a renowned player in the peak performance is intuitively more rewarding than defeating the same player in other periods. To account for this factor, we propose a dynamic variant of such a network-based ranking system and apply it to professional men's tennis data. We derive a set of linear online update equations for the score of each player. The proposed ranking system predicts the outcome of the future games with a higher accuracy than the static counterparts.Comment: 6 figure

    Omnivorousness in sport: The importance of social capital and networks

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    There has been for some time a significant and growing body of research around the relationship between sport and social capital. Similarly, within sociology there has been a corpus of work that has acknowledged the emergence of the omnivore–univore relationship. Surprisingly, relatively few studies examining sport and social capital have taken the omnivore–univore framework as a basis for understanding the relationship between sport and social capital. This gap in the sociology of sport literature and knowledge is rectified by this study that takes not Putnam, Coleman or Bourdieu, but Lin’s social network approach to social capital. The implications of this article are that researchers investigating sport and social capital need to understand more about how social networks and places for sport work to create social capital and, in particular, influence participating in sporting activities. The results indicate that social networks both facilitate and constrain sports participation; whilst family and friendship networks are central in active lifestyles, those who are less active have limited networks

    Social problems in oncology

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    A study was undertaken to describe, evaluate and categorise the social problems experienced by cancer patients. Ninety-six adult cancer patients at all stages of disease participated in either a telephone focus group discussion, a face to face focus group or an individual interview which were tape recorded and transcribed. Six experts analysed the transcripts. A total of 32 social problems were identified categorized under eight headings plus four single items. The categories were: problems with (1) managing in the home, (2) health and welfare services, (3) finances, (4) employment, (5) legal matters, (6) relationships, (7) sexuality and body image and (8) recreation. Problems with relationships and communication were the most frequently reported with financial, employment, body image and domestic problems also being widely endorsed. Female groups, younger patient groups and groups where the aim of treatment was palliative reported more social problems than other groups. Social problems are common and important to cancer patients. The social problems identified in this study will contribute to an item pool generated for developing a Social Problems Inventory that may be included in patient centred assessment as part of routine oncology practice

    Neutral lipid storage diseases as cellular model to study lipid droplet function

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    Neutral lipid storage disease with myopathy (NLSDM) and with ichthyosis (NLSDI) are rare autosomal recessive disorders caused by mutations in the PNPLA2 and in the ABHD5/CGI58 genes, respectively. These genes encode the adipose triglyceride lipase (ATGL) and \u3b1-\u3b2 hydrolase domain 5 (ABHD5) proteins, which play key roles in the function of lipid droplets (LDs). LDs, the main cellular storage sites of triacylglycerols and sterol esters, are highly dynamic organelles. Indeed, LDs are critical for both lipid metabolism and energy homeostasis. Partial or total PNPLA2 or ABHD5/CGI58 knockdown is characteristic of the cells of NLSD patients; thus, these cells are natural models with which one can unravel LD function. In this review we firstly summarize genetic and clinical data collected from NLSD patients, focusing particularly on muscle, skin, heart, and liver damage due to impaired LD function. Then, we discuss how NLSD cells were used to investigate and expand the current structural and functional knowledge of LD

    Evaluation of two interaction techniques for visualization of dynamic graphs

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    Several techniques for visualization of dynamic graphs are based on different spatial arrangements of a temporal sequence of node-link diagrams. Many studies in the literature have investigated the importance of maintaining the user's mental map across this temporal sequence, but usually each layout is considered as a static graph drawing and the effect of user interaction is disregarded. We conducted a task-based controlled experiment to assess the effectiveness of two basic interaction techniques: the adjustment of the layout stability and the highlighting of adjacent nodes and edges. We found that generally both interaction techniques increase accuracy, sometimes at the cost of longer completion times, and that the highlighting outclasses the stability adjustment for many tasks except the most complex ones.Comment: Appears in the Proceedings of the 24th International Symposium on Graph Drawing and Network Visualization (GD 2016

    Protocol for the Smoking, Nicotine and Pregnancy (SNAP) trial: double-blind, placebo-randomised, controlled trial of nicotine replacement therapy in pregnancy

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    Background: Smoking in pregnancy remains a public health challenge. Nicotine replacement therapy (NRT) is effective for smoking cessation in non-pregnant people, but because women metabolise nicotine and cotinine much faster in pregnancy, it is unclear whether this will be effective for smoking cessation in pregnancy. The NHS Health Technology Assessment Programme (HTA)-funded smoking, nicotine and pregnancy ( SNAP) trial will investigate whether or not nicotine replacement therapy ( NRT) is effective, cost-effective and safe when used for smoking cessation by pregnant women. Methods/Design: Over two years, in 5 trial centres, 1050 pregnant women who are between 12 and 24 weeks pregnant will be randomised as they attend hospital for ante-natal ultrasound scans. Women will receive either nicotine or placebo transdermal patches with behavioural support. The primary outcome measure is biochemically-validated, self-reported, prolonged and total abstinence from smoking between a quit date ( defined before randomisation and set within two weeks of this) and delivery. At six months after childbirth self-reported maternal smoking status will be ascertained and two years after childbirth, self-reported maternal smoking status and the behaviour, cognitive development and respiratory symptoms of children born in the trial will be compared in both groups. Discussion: This trial is designed to ascertain whether or not standard doses of NRT ( as transdermal patches) are effective and safe when used for smoking cessation during pregnancy

    Dapsone-induced agranulocytosis leading to perianal abscess and death: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Dapsone (diaminodiphenylsulfone) is used for the treatment of intractable skin diseases such as pemphigus and leprosy. The side effects of Dapsone are anemia, leukopenia, and liver dysfunction. Here, we present a case of agranulocytosis-induced septic shock, which was a side effect of Dapsone.</p> <p>Case presentation</p> <p>An 82-year-old Japanese woman was transferred to our hospital with fever, leucopenia, and respiratory arrest. At the previous hospital, she had been administered Dapsone for linear IgA bullous dermatosis. At the time of admission, she presented with methemoglobinemia and septic shock, which was due to immunosuppression caused by the normal dose of Dapsone. Although her overall health initially improved, her condition deteriorated because of septic shock caused by an anal fistula. She died of sepsis on hospital day 80.</p> <p>Conclusion</p> <p>One of the side effects of Dapsone is agranulocytosis. Patients with agranulocytosis may be in danger of developing anal fistula. Therefore, care must be taken if a patient with agranulocytosis develops a decubitus ulcer in the sacral region, since it could develop into a fistula-in-ano.</p
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