9,083 research outputs found

    Helminths in the hygiene hypothesis:Sooner or later?

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    There is increasing recognition that exposures to infectious agents evoke fundamental effects on the development and behaviour of the immune system. Moreover, where infections (especially parasitic infections) have declined, immune responses appear to be increasingly prone to hyperactivity. For example, epidemiological studies of parasite-endemic areas indicate that prenatal or early-life experience of infections can imprint an individual's immunological reactivity. However, the ability of helminths to dampen pathology in established inflammatory diseases implies that they can have therapeutic effects even if the immune system has developed in a low-infection setting. With recent investigations of how parasites are able to modulate host immune pathology at the level of individual parasite molecules and host cell populations, we are now able to dissect the nature of the host–parasite interaction at both the initiation and recall phases of the immune response. Thus the question remains – is the influence of parasites on immunity one that acts primarily in early life, and at initiation of the immune response, or in adulthood and when recall responses occur? In short, parasite immunosuppression – sooner or later

    Serial Position Effects in Short-term Visual Memory: A SIMPLE Explanation?

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    A version of Sternberg’s (1966) short-term, visual memory recognition paradigm with pictures of unfamiliar faces as stimuli was used in three experiments to assess the applicability of the distinctiveness based SIMPLE model proposed by Brown, Neath & Chater (2002). Initial simulations indicated that the amount of recency predicted increased as the parameter measuring the psychological distinctiveness of the stimulus material (c) increased, and that the amount of primacy was dependent on the extent of proactive interference from previously presented stimuli. The data from experiment 1, which used memory lists of four and five faces varying in visual similarity confirmed the predicted, extended recency effect. However, changes in visual similarity were not found to produce changes in c. In Experiments 2 and 3, the conditions that influence the magnitude of c were explored. These revealed that both the familiarity of the stimulus class before testing, and changes in familiarity due to perceptual learning, influenced distinctiveness as indexed by the parameter c. Overall the empirical data from all three experiments were well-fit by SIMPLE

    Nursing assistants’ experiences of administering manual restraint for compulsory nasogastric feeding of young persons with anorexia nervosa

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    Manual restraint, a type of physical restraint, is a common practice in inpatient mental health settings linked to adverse physical and psychological staff and patient outcomes. However, little is known about the use of manual restraint for compulsory nasogastric feeding of patients with anorexia nervosa within inpatient eating disorder settings. The present phenomenological study aimed to explore nursing assistants’ experiences of administering manual restraint for compulsory nasogastric feeding of young persons with anorexia nervosa. The study followed COREQ guidelines. Eight semi-structured interviews were conducted with eight nursing assistants from one UK inpatient child and adolescent eating disorder service. Interviews were transcribed verbatim and analysed using Thematic Analysis. Three themes were extracted: An unpleasant practice, Importance of coping, and Becoming desensitised and sensitised. Nursing assistants commonly experienced emotional distress, physical exhaustion, physical injury and physical aggression as a result of their manual restraint use. Nursing assistants appeared to cope with their distress by talking with colleagues and young persons who were further in their recovery, and by detaching themselves during manual restraint incidents. The findings highlight that the use of manual restraint for compulsory nasogastric feeding of young persons with anorexia nervosa in the UK, is a highly distressing practice for nursing assistants. It is therefore important that sufficient supervision, support and training is made available to staff working in these settings

    STOL aircraft transient ground effects. Part 1: Fundamental analytical study

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    The first phases of a fundamental analytical study of STOL ground effects were presented. Ground effects were studied in two dimensions to establish the importance of nonlinear effects, to examine transient aspects of ascent and descent near the ground, and to study the modelling of the jet impingement on the ground. Powered lift system effects were treated using the jet-flap analogy. The status of a three-dimensional jet-wing ground effect method was presented. It was shown, for two-dimensional unblown airfoils, that the transient effects are small and are primarily due to airfoil/freestream/ground orientation rather than to unsteady effects. The three-dimensional study showed phenomena similar to the two-dimensional results. For unblown wings, the wing/freestream/ground orientation effects were shown to be of the same order of magnitude as for unblown airfoils. This may be used to study the nonplanar, nonlinear, jet-wing ground effect

    Immediate replacement of fishing with dairying by the earliest farmers of the NE Atlantic archipelagos

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    The appearance of farming, from its inception in the Near East around 12 000 years ago, finally reached the northwestern extremes of Europe by the fourth millennium BC or shortly thereafter. Various models have been invoked to explain the Neolithization of northern Europe; however, resolving these different scenarios has proved problematic due to poor faunal preservation and the lack of specificity achievable for commonly applied proxies. Here, we present new multi-proxy evidence, which qualitatively and quantitatively maps subsistence change in the northeast Atlantic archipelagos from the Late Mesolithic into the Neolithic and beyond. A model involving significant retention of hunter–gatherer–fisher influences was tested against one of the dominant adoptions of farming using a novel suite of lipid biomarkers, including dihydroxy fatty acids, ω-(o-alkylphenyl)alkanoic acids and stable carbon isotope signatures of individual fatty acids preserved in cooking vessels. These new findings, together with archaeozoological and human skeletal collagen bulk stable carbon isotope proxies, unequivocally confirm rejection of marine resources by early farmers coinciding with the adoption of intensive dairy farming. This pattern of Neolithization contrasts markedly to that occurring contemporaneously in the Baltic, suggesting that geographically distinct ecological and cultural influences dictated the evolution of subsistence practices at this critical phase of European prehistory

    Phosphorus fertilizer placement and profitability.

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