433 research outputs found

    Alien Registration- Richard, Staley F. (Brunswick, Cumberland County)

    Get PDF
    https://digitalmaine.com/alien_docs/31657/thumbnail.jp

    “Beyond the conventional boundaries of physics”: On relating Ernst Mach’s philosophy to his teaching and research in the 1870s and 80s

    Get PDF
    Ernst Mach’s most well known critiques of mechanics concern mass, inertia and space and time. Conceptually motivated towards avoiding unnecessary assumptions and basing physical concepts on measured relations, they were first published in the years around 1870 (for mass and inertia) and in his well known 1883 book Die Mechanik in ihrer Entwickelung historisch-kritisch dargestellt, later translated as The Science of Mechanics: A Critical and Historical Account of its Development. Philosophical discussion of Mach’s critiques has reflected these conceptual concerns, connecting them to Mach’s account of science as the economical description of phenomena. Yet manuscript records of his teaching in the 1870s show that Mach was also animated by psychophysics and the relations between inner and outer worlds. His publications attest to these broader interests as well. In the 1870s, for example, Mach developed physiological studies of the sense of motion. Soon after completing his critical history of mechanics he took up the relations between physiology and psychology in his 1886 Beiträge zur Analyse der Empfindungen. By investigating Mach’s research across subject matter that has usually been treated separately, and integrating his teaching with his research, this chapter aims to offer a study of Mach’s philosophy as it is revealed in practice. Mach presents a highly unusual example of someone whose primary aim was to reform his own discipline of physics through the concerns of other disciplines, something he alluded to in 1886 when stating that he expected the next great enlightenments of the foundations of physics to come at the hands of biology

    Effects of Prior Success on Elicitation of the Fear of Failure Motive

    Get PDF
    Educational Psycholog

    Hedgerow rejuvenation management affects invertebrate communities through changes to habitat structure

    Get PDF
    Hedgerows are an important semi-natural habitat for invertebrates and other wildlife within agricultural landscapes. Hedgerow quality can be greatly affected either by over- or under-management. Neglect of hedgerows is an increasingly important issue as traditional management techniques such as hedgelaying become economically unviable. In the UK, funding for hedge management is available under agri-environment schemes but relatively little is known about how this impacts on wider biodiversity. We used a randomised block experiment to investigate how habitat structural change, arising from a range of techniques to rejuvenate hedgerows (including more economic/mechanised alternatives to traditional hedgelaying), affected invertebrate abundance and diversity. We combined digital image analysis with estimates of foliage biomass and quality to show which aspects of hedge structure were most affected by the rejuvenation treatments. All investigated aspects of habitat structure varied considerably with management type, though the abundance of herbivores and predators was affected primarily by foliage density. Detritivore abundance was most strongly correlated with variation in hedge gap size. The results suggest that habitat structure is an important organising force in invertebrate community interactions and that management technique may affect trophic groups differently. Specifically we find that alternative methods of hedgerow rejuvenation could support abundances of invertebrates comparable or even higher than traditional hedgelaying, with positive implications for the restoration of a larger area of hedgerow habitat on a limited budget

    Microbes in beach sands : integrating environment, ecology and public health

    Get PDF
    Author Posting. © The Author(s), 2014. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Reviews in Environmental Science and Bio/Technology 13 (2014): 329-368, doi:10.1007/s11157-014-9340-8.Beach sand is a habitat that supports many microbes, including viruses, bacteria, fungi and protozoa (micropsammon). The apparently inhospitable conditions of beach sand environments belie the thriving communities found there. Physical factors, such as water availability and protection from insolation; biological factors, such as competition, predation, and biofilm formation; and nutrient availability all contribute to the characteristics of the micropsammon. Sand microbial communities include autochthonous species/phylotypes indigenous to the environment. Allochthonous microbes, including fecal indicator bacteria (FIB) and waterborne pathogens, are deposited via waves, runoff, air, or animals. The fate of these microbes ranges from death, to transient persistence and/or replication, to establishment of thriving populations (naturalization) and integration in the autochthonous community. Transport of the micropsammon within the habitat occurs both horizontally across the beach, and vertically from the sand surface and ground water table, as well as at various scales including interstitial flow within sand pores, sediment transport for particle-associated microbes, and the large-scale processes of wave action and terrestrial runoff. The concept of beach sand as a microbial habitat and reservoir of FIB and pathogens has begun to influence our thinking about human health effects associated with sand exposure and recreational water use. A variety of pathogens have been reported from beach sands, and recent epidemiology studies have found some evidence of health risks associated with sand exposure. Persistent or replicating populations of FIB and enteric pathogens have consequences for watershed/beach management strategies and regulatory standards for safe beaches. This review summarizes our understanding of the community structure, ecology, fate, transport, and public health implications of microbes in beach sand. It concludes with recommendations for future work in this vastly under-studied area.2015-05-0

    Re-structuring hedges: rejuvenation management can improve the long term quality of hedgerow habitats for wildlife in the UK

    Get PDF
    Hedgerows provide key wildlife habitat in intensive agricultural landscapes, but are declining in length and structural condition due to a lack of rejuvenation management, neglect and over-frequent trimming with mechanised flails. Here, we test cheaper, alternative methods to traditional hedge laying methods using a multi-site manipulative field experiment. In the first quantitative test of new approaches to hedge rejuvenation management, hedge regrowth, structure, berry provision for over-wintering wildlife and cost of rejuvenation were assessed in response to five methods, for three years following rejuvenation. Three ‘laying’ methods and coppicing were effective at improving hedgerow condition by stimulating basal regrowth, thus increasing the density of woody material at the base and reducing gap size. The pros and cons of coppicing are discussed in relation to its impact on different wildlife groups, and it is recommended in limited circumstances. Differences between the three ‘laying’ methods reduced over time, so a cheaper conservation hedging method is recommended as an alternative to traditional hedge laying. This new approach to hedge management offers the potential to restore twice the length of hedgerow currently rejuvenated under agri-environment schemes

    Phylum Verrucomicrobia representatives share a compartmentalized cell plan with members of bacterial phylum Planctomycetes

    Get PDF
    BACKGROUND: The phylum Verrucomicrobia is a divergent phylum within domain Bacteria including members of the microbial communities of soil and fresh and marine waters; recently extremely acidophilic members from hot springs have been found to oxidize methane. At least one genus, Prosthecobacter, includes species with genes homologous to those encoding eukaryotic tubulins. A significant superphylum relationship of Verrucomicrobia with members of phylum Planctomycetes possessing a unique compartmentalized cell plan, and members of the phylum Chlamydiae including human pathogens with a complex intracellular life cycle, has been proposed. Based on the postulated superphylum relationship, we hypothesized that members of the two separate phyla Planctomycetes and Verrucomicrobia might share a similar ultrastructure plan differing from classical prokaryote organization. RESULTS: The ultrastructure of cells of four members of phylum Verrucomicrobia – Verrucomicrobium spinosum, Prosthecobacter dejongeii, Chthoniobacter flavus, and strain Ellin514 – was examined using electron microscopy incorporating high-pressure freezing and cryosubstitution. These four members of phylum Verrucomicrobia, representing 3 class-level subdivisions within the phylum, were found to possess a compartmentalized cell plan analogous to that found in phylum Planctomycetes. Like all planctomycetes investigated, they possess a major pirellulosome compartment containing a condensed nucleoid and ribosomes surrounded by an intracytoplasmic membrane (ICM), as well as a ribosome-free paryphoplasm compartment between the ICM and cytoplasmic membrane. CONCLUSION: A unique compartmentalized cell plan so far found among Domain Bacteria only within phylum Planctomycetes, and challenging our concept of prokaryote cell plans, has now been found in a second phylum of the Domain Bacteria, in members of phylum Verrucomicrobia. The planctomycete cell plan thus occurs in at least two distinct phyla of the Bacteria, phyla which have been suggested from other evidence to be related phylogenetically in the proposed PVC (Planctomycetes-Verrucomicrobia-Chlamydiae) superphylum. This planctomycete cell plan is present in at least 3 of 6 subdivisions of Verrucomicrobia, suggesting that the common ancestor of the verrucomicrobial phylum was also compartmentalized and possessed such a plan. The presence of this compartmentalized cell plan in both phylum Planctomycetes and phylum Verrucomicrobia suggest that the last common ancestor of these phyla was also compartmentalized
    corecore