162 research outputs found

    Assembly of Miscible Supramolecular Network Blends Using DDA·AAD Hydrogen-Bonding Interactions of Pendant Side-Chains

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    The formation of polymer blends can result in materials with superior properties through combination of homo- or co-polymers with divergent functionalities. However, the contrasting physical properties of different polymers often result in phase separation. Herein we induce miscible blend formation of immiscible poly(methyl methacrylate) and polystyrene polymers through triple donor–donor–acceptor and acceptor–acceptor–donor (DDA·AAD) hydrogen bonding between complementary heterodimers on pendent side-chains. RAFT polymerization is used to synthesize a series of poly (methylmethacrylate) and polystyrene co-polymers bearing complementary side-chain hydrogen bonding motifs. Mixing of these polymers promoted miscible blend formation as demonstrated by atomic force microscopy and differential scanning calorimetry. The effectiveness of blend formation was shown to depend upon the extent of incorporation of hydrogen-bonding motif bearing co-monomer; lower degrees of incorporation lead to ineffective blending, whereas higher degree of incorporation, suppress phase separation and promote miscibility

    Spatially Explicit Data: Stewardship and Ethical Challenges in Science

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    Scholarly communication is at an unprecedented turning point created in part by the increasing saliency of data stewardship and data sharing. Formal data management plans represent a new emphasis in research, enabling access to data at higher volumes and more quickly, and the potential for replication and augmentation of existing research. Data sharing has recently transformed the practice, scope, content, and applicability of research in several disciplines, in particular in relation to spatially specific data. This lends exciting potentiality, but the most effective ways in which to implement such changes, particularly for disciplines involving human subjects and other sensitive information, demand consideration. Data management plans, stewardship, and sharing, impart distinctive technical, sociological, and ethical challenges that remain to be adequately identified and remedied. Here, we consider these and propose potential solutions for their amelioration

    A study of tuberculosis in road traffic-killed badgers on the edge of the British bovine TB epidemic area

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    The role of badgers in the geographic expansion of the bovine tuberculosis (bTB) epidemic in England is unknown: indeed there have been few published studies of bTB in badgers outside of the Southwest of England where the infection is now endemic in cattle. Cheshire is now on the edge of the expanding area of England in which bTB is considered endemic in cattle. Previous studies, over a decade ago when bovine infection was rare in Cheshire, found no or only few infected badgers in the south eastern area of the county. In this study, carried out in 2014, road-killed badgers were collected through a network of local stakeholders (farmers, veterinarians, wildlife groups, government agencies), and Mycobacterium bovis was isolated from 21% (20/94) badger carcasses. Furthermore, there was strong evidence for co-localisation of M. bovis SB0129 (genotype 25) infection in both badgers and cattle herds at a county scale. While these findings suggest that both badgers and cattle are part of the same geographically expanding epidemic, the direction of any cross-species transmission and the drivers of this expansion cannot be determined. The study also demonstrated the utility of using road-killed badgers collected by stakeholders as a means of wildlife TB surveillance

    Impaired psychological recovery in the elderly after the Niigata-Chuetsu Earthquake in Japan:a population-based study

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    BACKGROUND: An earthquake measuring 6.8 on the Richter scale struck the Niigata-Chuetsu region of Japan at 5.56 P.M. on the 23rd of October, 2004. The earthquake was followed by sustained occurrence of numerous aftershocks, which delayed reconstruction of community lifelines. Even one year after the earthquake, 9,160 people were living in temporary housing. Such a devastating earthquake and life after the earthquake in an unfamiliar environment should cause psychological distress, especially among the elderly. METHODS: Psychological distress was measured using the 12-item General Health Questionnaire (GHQ-12) in 2,083 subjects (69% response rate) who were living in transient housing five months after the earthquake. GHQ-12 was scored using the original method, Likert scoring and corrected method. The subjects were asked to assess their psychological status before the earthquake, their psychological status at the most stressful time after the earthquake and their psychological status at five months after the earthquake. Exploratory and confirmatory factor analysis was used to reveal the factor structure of GHQ12. Multiple regression analysis was performed to analyze the relationship between various background factors and GHQ-12 score and its subscale. RESULTS: GHQ-12 scores were significantly elevated at the most stressful time and they were significantly high even at five months after the earthquake. Factor analysis revealed that a model consisting of two factors (social dysfunction and dysphoria) using corrected GHQ scoring showed a high level of goodness-of-fit. Multiple regression analysis revealed that age of subjects affected GHQ-12 scores. GHQ-12 score as well as its factor 'social dysfunction' scale were increased with increasing age of subjects at five months after the earthquake. CONCLUSION: Impaired psychological recovery was observed even at five months after the Niigata-Chuetsu Earthquake in the elderly. The elderly were more affected by matters relating to coping with daily problems

    Citizen science for observing and understanding the Earth

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    Citizen Science, or the participation of non-professional scientists in a scientific project, has a long history—in many ways, the modern scientific revolution is thanks to the effort of citizen scientists. Like science itself, citizen science is influenced by technological and societal advances, such as the rapid increase in levels of education during the latter part of the twentieth century, or the very recent growth of the bidirectional social web (Web 2.0), cloud services and smartphones. These transitions have ushered in, over the past decade, a rapid growth in the involvement of many millions of people in data collection and analysis of information as part of scientific projects. This chapter provides an overview of the field of citizen science and its contribution to the observation of the Earth, often not through remote sensing but a much closer relationship with the local environment. The chapter suggests that, together with remote Earth Observations, citizen science can play a critical role in understanding and addressing local and global challenges

    Description of Hymenolepis microstoma (Nottingham strain): a classical tapeworm model for research in the genomic era

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    <p>Abstract</p> <p>Background</p> <p><it>Hymenolepis microstoma </it>(Dujardin, 1845) Blanchard, 1891, the mouse bile duct tapeworm, is a rodent/beetle-hosted laboratory model that has been used in research and teaching since its domestication in the 1950s. Recent characterization of its genome has prompted us to describe the specific strain that underpins these data, anchoring its identity and bringing the 150+ year-old original description up-to-date.</p> <p>Results</p> <p>Morphometric and ultrastructural analyses were carried out on laboratory-reared specimens of the 'Nottingham' strain of <it>Hymenolepis microstoma </it>used for genome characterization. A contemporary description of the species is provided including detailed illustration of adult anatomy and elucidation of its taxonomy and the history of the specific laboratory isolate.</p> <p>Conclusions</p> <p>Our work acts to anchor the specific strain from which the <it>H. microstoma </it>genome has been characterized and provides an anatomical reference for researchers needing to employ a model tapeworm system that enables easy access to all stages of the life cycle. We review its classification, life history and development, and briefly discuss the genome and other model systems being employed at the beginning of a genomic era in cestodology.</p

    Timbre from Sound Synthesis and High-level Control Perspectives

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    International audienceExploring the many surprising facets of timbre through sound manipulations has been a common practice among composers and instrument makers of all times. The digital era radically changed the approach to sounds thanks to the unlimited possibilities offered by computers that made it possible to investigate sounds without physical constraints. In this chapter we describe investigations on timbre based on the analysis by synthesis approach that consists in using digital synthesis algorithms to reproduce sounds and further modify the parameters of the algorithms to investigate their perceptual relevance. In the first part of the chapter timbre is investigated in a musical context. An examination of the sound quality of different wood species for xylophone making is first presented. Then the influence of instrumental control on timbre is described in the case of clarinet and cello performances. In the second part of the chapter, we mainly focus on the identification of sound morphologies, so called invariant sound structures responsible for the evocations induced by environmental sounds by relating basic signal descriptors and timbre descriptors to evocations in the case of car door noises, motor noises, solid objects, and their interactions

    Investigation of the midgut structure and ultrastructure in Cimex lectularius and Cimex pipistrelli (Hemiptera, Cimicidae)

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    Cimicidae are temporary ectoparasites, which means that they cannot obtain food continuously. Both Cimex species examined here, Cimex lectularius (Linnaeus 1758) and Cimex pipistrelli (Jenyns 1839), can feed on a non-natal host, C. lectularius from humans on bats, C. pipistrelli on humans, but never naturally. The midgut of C. lectularius and C. pipistrelli is composed of three distinct regions—the anterior midgut (AMG), which has a sack-like shape, the long tube-shaped middle midgut (MMG), and the posterior midgut (PMG). The different ultrastructures of the AMG, MMG, and PMG in both of the species examined suggest that these regions must fulfill different functions in the digestive system. Ultrastructural analysis showed that the AMG fulfills the role of storing food and synthesizing and secreting enzymes, while the MMG is the main organ for the synthesis of enzymes, secretion, and the storage of the reserve material. Additionally, both regions, the AMG and MMG, are involved in water absorption in the digestive system of both Cimex species. The PMG is the part of the midgut in which spherites accumulate. The results of our studies confirm the suggestion of former authors that the structure of the digestive tract of insects is not attributed solely to diet but to the basic adaptation of an ancestor
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