3,617 research outputs found

    Absolute absorption and fluorescence measurements over a dynamic range of 106^6 with cavity-enhanced laser-induced fluorescence

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    We describe a novel experimental setup that combines the advantages of both laser-induced fluorescence and cavity ring-down techniques. The simultaneous and correlated measurement of the ring-down and fluorescence signals yields absolute absorption coefficients for the fluorescence measurement. The combined measurement is conducted with the same sample in a single, pulsed laser beam. The fluorescence measurement extends the dynamic range of a stand-alone cavity ring-down setup from typically three to at least six orders of magnitude. The presence of the cavity improves the quality of the signal, in particular the signal-to-noise ratio. The methodology, dubbed cavity-enhanced laser-induced fluorescence (CELIF), is developed and rigorously tested against the spectroscopy of 1,4-bis(phenylethynyl)benzene in a molecular beam and density measurements in a cell. We outline how the method can be utilised to determine absolute quantities: absorption cross sections, sample densities and fluorescence quantum yields.Comment: 12 pages, 6 figures, submitted to J. Chem. Phy

    Absolute fluorescence and absorption measurements over a dynamic range of 106 with cavity-enhanced laser-induced fluorescence

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    We present a novel spectroscopic technique that exhibits high sensitivity and a large dynamic range for the measurement of absolute absorption coefficients. We perform a simultaneous and correlated laser-induced fluorescence and cavity ring-down measurement of the same sample in a single pulsed laser beam. The combined measurement offers a large dynamic range and a lower limit of detection than either technique on its own. The methodology, dubbed cavity-enhanced laser-induced fluorescence, is developed and rigorously tested against the electronic spectroscopy of 1,4-bis(phenylethynyl)benzene in a molecular beam and density measurements in a cell. We outline how the method can be used to determine absolute quantities, such as sample densities, absorption cross sections, and fluorescence quantum yields, particularly in spatially confined samples

    The impact of privatisation on union membership and density: A Western Australian case study

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    Falling membership numbers and declining union density are issues of concern for many Australian unions. Australian Bureau of Statistics figures show that between 2005 and 2008, trade union membership declined from 22.4% to 18.9% of the workforce. Studies and statistics consistently show that union membership and density are lowest in Western Australia, despite trend reversals elsewhere. Using the Western Australian branches of two 'blue-collar' unions - the Australian Rail, Tram and Bus Industry Union, Western Australian Branch and the Australian Manufacturing Workers' Union, covering a range of transport, metal working, printing and manufacturing trades - as examples, this article examines whether privatisation has contributed significantly to falling trade union density and membership in this state. These unions represented large public sector workforces. In order to test the hypothesis that privatisation has adversely affected union membership and density, the article examines three areas: changing policies in the Australian Labor Party, the breaking down of union culture and changes in trade training, and concludes that privatisation is a significant factor in the recent decline of these two unions

    Success stories and emerging themes in conservation physiology

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    The potential benefits of physiology for conservation are well established and include greater specificity of management techniques, determination of cause–effect relationships, increased sensitivity of health and disturbance monitoring and greater capacity for predicting future change. While descriptions of the specific avenues in which conservation and physiology can be integrated are readily available and important to the continuing expansion of the discipline of ‘conservation physiology’, to date there has been no assessment of how the field has specifically contributed to conservation success. However, the goal of conservation physiology is to foster conservation solutions and it is therefore important to assess whether physiological approaches contribute to downstream conservation outcomes and management decisions. Here, we present eight areas of conservation concern, ranging from chemical contamination to invasive species to ecotourism, where physiological approaches have led to beneficial changes in human behaviour, management or policy. We also discuss the shared characteristics of these successes, identifying emerging themes in the discipline. Specifically, we conclude that conservation physiology: (i) goes beyond documenting change to provide solutions; (ii) offers a diversity of physiological metrics beyond glucocorticoids (stress hormones); (iii) includes approaches that are transferable among species, locations and times; (iv) simultaneously allows for human use and benefits to wildlife; and (v) is characterized by successes that can be difficult to find in the primary literature. Overall, we submit that the field of conservation physiology has a strong foundation of achievements characterized by a diversity of conservation issues, taxa, physiological traits, ecosystem types and spatial scales. We hope that these concrete successes will encourage the continued evolution and use of physiological tools within conservation-based research and management plans."This work was supported by the Society for Integrative and Comparative Biology; the University of Windsor, Ontario, Canada; Dalhousie University, Nova Scotia, Canada; and the Canadian Society of Zoologists. C.L.M. was supported by a Natural Sciences and Engineering Research Council of Canada PGS-D (427552). S.J.C. and O.P.L. are supported by the Canada Research Chairs program. E.J.C. was supported by a grant from the National Science Foundation (BCS-1134687). K.R.H. was supported by grants from the National Science Foundation’s MacroSystems Biology program (award no. 1340856) and the US Department of Agriculture (NRI 2015-67013-23138). J.R.R. was supported by grants from the National Science Foundation (EF-1241889), National Institutes of Health (R01GM109499, R01TW010286), US Department of Agriculture (NRI 2006-01370, 2009-35102-0543) and US Environmental Protection Agency (CAREER 83518801)."https://academic.oup.com/conphys/article/4/1/cov057/295129

    From inclusion to independence – Training consumers to review research

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    Health and medical research invariably impacts on the lives of everyday people. Organisations in the developed world are increasingly involving the public in health research projects, and research governance structures and processes. The form the involvement takes varies, as does the level of involvement, from individuals, to groups, to the wider community. Lay community members can be trained to independently review health and medical research, and wider societal involvement in funding decisions, can be effectively fostered. The theoretical foundation, design and development of a task based consumer-training program, including a number of enabling factors to support the success of such training are presented. This work is likely to be of value to those planning to train consumers in technical or complex areas

    Success stories and emerging themes in conservation physiology

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    The potential benefits of physiology for conservation are well established and include greater specificity of management techniques, determination of cause-effect relationships, increased sensitivity of health and disturbance monitoring and greater capacity for predicting future change. While descriptions of the specific avenues in which conservation and physiology can be integrated are readily available and important to the continuing expansion of the discipline of \u27conservation physiology\u27, to date there has been no assessment of how the field has specifically contributed to conservation success. However, the goal of conservation physiology is to foster conservation solutions and it is therefore important to assess whether physiological approaches contribute to downstream conservation outcomes and management decisions. Here, we present eight areas of conservation concern, ranging from chemical contamination to invasive species to ecotourism, where physiological approaches have led to beneficial changes in human behaviour, management or policy. We also discuss the shared characteristics of these successes, identifying emerging themes in the discipline. Specifically, we conclude that conservation physiology: (i) goes beyond documenting change to provide solutions; (ii) offers a diversity of physiological metrics beyond glucocorticoids (stress hormones); (iii) includes approaches that are transferable among species, locations and times; (iv) simultaneously allows for human use and benefits to wildlife; and (v) is characterized by successes that can be difficult to find in the primary literature. Overall, we submit that the field of conservation physiology has a strong foundation of achievements characterized by a diversity of conservation issues, taxa, physiological traits, ecosystem types and spatial scales. We hope that these concrete successes will encourage the continued evolution and use of physiological tools within conservation-based research and management plans

    The Impact of Global Warming and Anoxia on Marine Benthic Community Dynamics: an Example from the Toarcian (Early Jurassic)

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    The Pliensbachian-Toarcian (Early Jurassic) fossil record is an archive of natural data of benthic community response to global warming and marine long-term hypoxia and anoxia. In the early Toarcian mean temperatures increased by the same order of magnitude as that predicted for the near future; laminated, organic-rich, black shales were deposited in many shallow water epicontinental basins; and a biotic crisis occurred in the marine realm, with the extinction of approximately 5% of families and 26% of genera. High-resolution quantitative abundance data of benthic invertebrates were collected from the Cleveland Basin (North Yorkshire, UK), and analysed with multivariate statistical methods to detect how the fauna responded to environmental changes during the early Toarcian. Twelve biofacies were identified. Their changes through time closely resemble the pattern of faunal degradation and recovery observed in modern habitats affected by anoxia. All four successional stages of community structure recorded in modern studies are recognised in the fossil data (i.e. Stage III: climax; II: transitional; I: pioneer; 0: highly disturbed). Two main faunal turnover events occurred: (i) at the onset of anoxia, with the extinction of most benthic species and the survival of a few adapted to thrive in low-oxygen conditions (Stages I to 0) and (ii) in the recovery, when newly evolved species colonized the re-oxygenated soft sediments and the path of recovery did not retrace of pattern of ecological degradation (Stages I to II). The ordination of samples coupled with sedimentological and palaeotemperature proxy data indicate that the onset of anoxia and the extinction horizon coincide with both a rise in temperature and sea level. Our study of how faunal associations co-vary with long and short term sea level and temperature changes has implications for predicting the long-term effects of “dead zones” in modern oceans

    Embedded Research::a promising way to create evidence-informed impact in public health?

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    Background Embedded research (ER) is recognized as one way to strengthen the integration of evidence into public health (PH) practice. In this paper, we outline a promising example of the co-production of research evidence between Fuse, the UKCRC Centre for Translational Research in Public Health and a local authority (LA) in north east England. Methods We critically examine attempts to share and use research findings to influence decision-making in a LA setting, drawing on insights from PH practitioners, managers, commissioners and academic partners involved in this organizational case study. We highlight what can be achieved as a co-located embedded researcher. Results The benefits and risks of ER are explored, alongside our reflections on the added value of this approach and the institutional prerequisites necessary for it to work. We argue that while this is not a new methodological approach, its application in PH as a way to facilitate evidence use is novel, and raises pragmatic and theoretical questions about the nature of impact and the extent to which it can be engineered. Conclusion With increased situated understanding of organizational culture and norms and greater awareness of the socio-political realities of PH, ER enables new co-produced solutions to become possible

    First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

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    Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

    Codesigning a Measure of Person-Centred Coordinated Care to Capture the Experience of the Patient: The Development of the P3CEQ

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    Background: Person-centred coordinated care (P3C) is a priority for stakeholders (ie, patients, carers, professionals, policy makers). As a part of the development of an evaluation framework for P3C, we set out to identify patient-reported experience measures (PREMs) suitable for routine measurement and feedback during the development of services. Methods: A rapid review of the literature was undertaken to identity existing PREMs suitable for the probing person-centred and/or coordinated care. Of 74 measures identified, 7 met our inclusion criteria. We critically examined these against core domains and subdomains of P3C. Measures were then presented to stakeholders in codesign workshops to explore acceptability, utility, and their strengths/weaknesses. Results: The Long-Term Condition 6 questionnaire was preferred for its short length, utility, and tone. However, it lacked key questions in each core domain, and in response to requests from our codesign group, new questions were added to cover consideration as a whole person, coordination, care plans, carer involvement, and a single coordinator. Cognitive interviews, on-going codesign, and mapping to core P3C domains resulted in the refinement of the questionnaire to 11 items with 1 trigger question. The 11-item modified version was renamed the P3C Experiences Questionnaire. Conclusions: Due to a dearth of brief measures available to capture people’s experience of P3C for routine practice, an existing measure was modified using an iterative process of adaption and validation through codesign workshops. Next steps include psychometric validation and modification for people with dementia and learning difficulties.</p
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