1,132 research outputs found

    Growth and yield responses to amending the sugarcane monoculture: interactions between break history and nitrogen fertiliser

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    Experiments were established in the Burdekin Irrigation Area in North Queensland, Australia, to measure whether yield improvements from breaking the sugarcane monoculture or fumigating the soil could be modified by the application of different rates of nitrogen (N) fertiliser. Experiments were conducted in consecutive crop cycles (phase 1, planted 1998; phase 2, planted 2001) using the variety Q117, with the interaction between N applications and rotation histories discussed for the two plant crops. Histories consisted of alternate crop, bare fallow or mixed grass-legume pastures for periods of 42-66 months, compared with continuous cane as plough-out replant without (PORP) or with (PORP-F) soil fumigation. The N strategies involved combinations of N rates (0-180kgN/ha) and application times (at planting, 90 days after planting (DAP) or split between these times) in phase 1 and N rates (0-300kgN/ha) in phase 2. Histories had differing effects on N available to the cane crop and hence on response to N fertiliser. Some combinations of history and N rate were N-limited and strong linear relationships between biomass production or cane yield and crop N content could be developed. Critical N contents for biomass production (R2≤0.93) and fresh-weight cane yield (R2≤0.88) were 1.42 and 0.57kgN/t, respectively. Application of N fertiliser was shown to have significant impacts on both tiller addition and the retention of tillers to produce harvestable stalks. However, the application of fertiliser N had limited (phase 1) or no (phase 2) capacity to provide the quantum of yield response in soil health benefits associated with breaking the sugarcane monoculture. Increasing N application rates above that required to optimise crop yield resulted in significant decreases in sugar content of cane and thus lower sugar yields. Yield increases solely from improved soil health (i.e. exclusive of N response) constituted advantages averaging 15% (phase 1) to 20% (phase 2) compared with PORP. These effects were manifest early in the establishment of primary shoots in the plant crops, although the longevity of these benefits was limited. Replanting cane after a 3-year crop cycle (plant, 1st and 2nd ratoon) on land that had been under pasture, crop, bare fallow or PORP-F histories (phase 2, cycle 2) showed carryover effects of histories on N availability and fertiliser N responsiveness, but limited yield impacts attributable to residual soil health benefits. These results reinforce the importance of crop rotation during breaks between sugarcane cycles to maintain soil health and improve crop productivity

    A Study of the Structure and Associated Features of Sheep Mountain Anticline Big Horn County, Wyoming

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    A study was made of the joint sets developed within two stratigraphic units of significantly different ages in the Sheep Mountain region, Bighorn County, Wyoming, in an attempt to determine if any pre-Laramide orogeny existed in the area. The field methods used and the relationships exhibited between joint sets are discussed. From the data presented, no significant support of the premise is concluded

    A qualitative synthesis of diabetes self-management strategies for long term medical outcomes and quality of life in the UK

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    Open access article available from the publisher via doi: 10.1186/1472-6963-14-348BACKGROUND: Qualitative research on self-management for people with Type 2 Diabetes Mellitus (T2DM) has typically reported one-off retrospective accounts of individuals' strategies. The aim of this research was to identify the ways in which self-management strategies are perceived by people with T2DM as being either supportive or unsupportive over time, by using qualitative findings from both longitudinal intervention studies and usual care. METHODS: A systematic review of qualitative literature, published between 2000 and 2013, was conducted using a range of searching techniques. 1374 prospective qualitative papers describing patients' experiences of self-management strategies for T2DM were identified and screened. Of the 98 papers describing qualitative research conducted in the UK, we identified 4 longitudinal studies (3 intervention studies, 1 study of usual care). Key concepts and themes were extracted, reviewed and synthesised using meta-ethnography techniques. RESULTS: Aspects of self-management strategies in clinical trials (e.g. supported exercise regimens) can be perceived as enabling the control of biomarkers and facilitative of quality of life. In contrast, aspects of self-management strategies outwith trial conditions (e.g. self-monitoring) can be perceived of as negative influences on quality of life. For self-management strategies to be sustainable in the long term, patients require a sense of having a stake in their management that is appropriate for their beliefs and perceptions, timely information and support, and an overall sense of empowerment in managing their diabetes in relation to other aspects of their life. This enables participants to develop flexible diabetes management strategies that facilitate quality of life and long term medical outcomes. CONCLUSIONS: This synthesis has explored how patients give meaning to the experiences of interventions for T2DM and subsequent attempts to balance biomarkers with quality of life in the long term. People with T2DM both construct and draw upon causal accounts as a resource, and a means to counter their inability to balance medical outcomes and quality of life. These accounts can be mediated by the provision of timely and tailored information and support over time, which can allow people to develop a flexible regimen that can facilitate both quality of life and medical outcomes.National Institute for Health Research (NIHR

    Affine configurations and pure braids

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    We show that the fundamental group of the space of ordered affine-equivalent configurations of at least five points in the real plane is isomorphic to the pure braid group modulo its centre. In the case of four points this fundamental group is free with eleven generators.Comment: 5 pages, 1 figure, final version; to appear in Discrete & Computational Geometry, available from the publishers at http://www.springerlink.com/content/384516n7q24811ph

    Semiautomated text analytics for qualitative data synthesis

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    Approaches to synthesizing qualitative data have, to date, largely focused on integrating the findings from published reports. However, developments in text mining software offer the potential for efficient analysis of large pooled primary qualitative datasets. This case study aimed to (a) provide a step‐by‐step guide to using one software application, Leximancer, and (b) interrogate opportunities and limitations of the software for qualitative data synthesis. We applied Leximancer v4.5 to a pool of five qualitative, UK‐based studies on transportation such as walking, cycling, and driving, and displayed the findings of the automated content analysis as intertopic distance maps. Leximancer enabled us to “zoom out” to familiarize ourselves with, and gain a broad perspective of, the pooled data. It indicated which studies clustered around dominant topics such as “people.” The software also enabled us to “zoom in” to narrow the perspective to specific subgroups and lines of enquiry. For example, “people” featured in men's and women's narratives but were talked about differently, with men mentioning “kids” and “old,” whereas women mentioned “things” and “stuff.” The approach provided us with a fresh lens for the initial inductive step in the analysis process and could guide further exploration. The limitations of using Leximancer were the substantial data preparation time involved and the contextual knowledge required from the researcher to turn lines of inquiry into meaningful insights. In summary, Leximancer is a useful tool for contributing to qualitative data synthesis, facilitating comprehensive and transparent data coding but can only inform, not replace, researcher‐led interpretive work

    Preventing unintentional injuries to children under 15 years in the outdoors: a systematic review of the effectiveness of educational programs.

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    This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.Unintentional injuries to children in the outdoors have a significant impact on child mortality, development and healthcare costs. This paper presents the findings of a systematic review about the effectiveness of programs that provided information, advice or education about the prevention of unintentional injuries to children under 15 years during outdoor play and leisure.Centre for Public Health Excellence, National Institute for Health and Clinical Excellence (UK

    "It has no meaning to me". How do researchers understand the effectiveness of literature searches? A qualitative analysis and preliminary typology of understandings

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    This study aimed to address the question: what does “effectiveness” mean to researchers in the context of literature searching for systematic reviews? We conducted a thematic analysis of responses to an e‐mail survey. Eighty‐nine study authors, whose studies met inclusion in a recent review (2018), were contacted via e‐mail and asked three questions; one directly asking the question: in literature searching, what does effective (or effectiveness in) literature searching mean to you? Thirty‐eight (46%) responses were received from diverse professional groups, including: literature searchers, systematic reviewers, clinicians and researchers. A shared understanding of what effectiveness means was not identified. Instead, five themes were developed from data: 1) effectiveness is described as a metric; 2) effectiveness is a balance between metrics; 3) effectiveness can be categorised by search purpose; 4) effectiveness is an outcome; and, 5) effectiveness is an experimental concept. We propose that these themes constitute a preliminary typology of understandings. No single definition of effectiveness was identified. The proposed typology suggests that different researchers have differing understandings of effectiveness. This could lead to uncertainty as to the aim and the purpose of literature searches and confusion about the outcomes. The typology offers a potential route for further exploration

    A novel cellular pathway of antigen presentation and CD4 T cell activation in vivo

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    Dendritic cell activation of CD4 T cells in the lymph node draining a site of infection or vaccination is widely considered the central event in initiating adaptive immunity. The accepted dogma is that this occurs by stimulating local activation and antigen acquisition by dendritic cells, with subsequent lymph node migration, however the generalizability of this mechanism is unclear. Here we show that in some circumstances antigen can bypass the injection site inflammatory response, draining freely and rapidly to the lymph nodes where it interacts with subcapsular sinus (SCS) macrophages resulting in their death. Debris from these dying SCS macrophages is internalized by monocytes recruited from the circulation. This coordinated response leads to antigen presentation by monocytes and interactions with naïve CD4 T cells that can drive the initiation of T cell and B cell responses. These studies demonstrate an entirely novel pathway leading to initiation of adaptive immune responses in vivo
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