1,558 research outputs found

    Hemoglobin genotype has minimal influence on the physiological response of juvenile atlantic cod (Gadus morhua) to environmental challenges

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    Hemoglobin (Hb) polymorphism in cod is associated with temperature‐related differences in biogeographical distribution, and several authors have suggested that functional characteristics of the various hemoglobin isoforms (HbIs) directly influence phenotypic traits such as growth rate. However, no study has directly examined whether Hb genotype translates into physiological differences at the whole animal level. Thus, we generated a family of juvenile Atlantic cod consisting of all three main Hb genotypes (HbI‐1/1, HbI‐2/2, and HbI‐1/2) by crossing a single pair of heterozygous parents, and we compared their metabolic and cortisol responses to an acute thermal challenge (10&deg;C to their critical thermal maximum [CTM] or 22&deg;C, respectively) and tolerance of graded hypoxia. There were no differences in routine metabolism (at 10&deg;C), maximum metabolic rate, metabolic scope, CTM (overall mean 22.9&deg; &plusmn; 0.2&deg;C), or resting and poststress plasma cortisol levels among Hb genotypes. Further, although the HbI‐1/1 fish grew more (by 15%&ndash;30% during the first 9 mo) when reared at 10&deg; &plusmn; 1&deg;C and had a slightly enhanced hypoxia tolerance at 10&deg;C (e.g., the critical O2 levels for HbI‐1/1, HbI‐2/2, and HbI‐1/2 cod were 35.56% &plusmn; 1.24%, and 40.20% &plusmn; 1.99% air saturation, respectively), these results are contradictory to expectations based on HbI functional properties. Thus, our findings (1) do not support previous assumptions that growth rate differences among cod Hb genotypes result from a more efficient use of the oxygen supply&mdash;that is, reduced standard metabolic rates and/or increased metabolic capacity&mdash;and (2) suggest that in juvenile cod, there is no selective advantage to having a particular Hb genotype with regards to the capacity to withstand ecologically relevant environmental challenges.<br /

    The temperature of Britain's coalfields

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    Low temperature heat recovery, cooling and storage schemes, using abandoned flooded mine workings are a viable option for low carbon heating solutions within many abandoned British coalfields. The temperature of mine water is a useful parameter, coupled with depth to water, sustainable yield and recharge potential, to identify suitable locations and calculate the likely performance of heat recovery schemes. This paper aims to provide the first mapping and synthesis of the temperature of Britain's coalfields to support this emerging technology. Using the best available evidence, a median geothermal gradient of 24.1 °C/km was calculated for the British coalfields. However, geothermal gradients between separate coalfields can vary from 17.3 to 34.3 °C/km. The North East, Cumbria and Yorkshire coalfields all have mean geothermal gradients generally >30 °C/km, whilst geothermal gradients of generally <23 °C/km are measured in the Warwickshire, South Wales, Staffordshire, Douglas and Fife coalfields. Active dewatering schemes are shown to locally increase the apparent measured geothermal gradient by ingress and mixing of deeper water into the pumping shafts. This baseline spatial mapping and synthesis of coalfield temperatures offers significant benefit to those planning, designing and regulating heat recovery and storage in Britain's abandoned coalfields

    Global Governance Behind Closed Doors : The IMF Boardroom, the Enhanced Structural Adjustment Facility, and the Intersection of Material Power and Norm Change in Global Politics

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    Up on the 12th floor of its 19th Street Headquarters, the IMF Board sits in active session for an average of 7 hours per week. Although key matters of policy are decided on in the venue, the rules governing Boardroom interactions remain opaque, resting on an uneasy combination of consensual decision-making and weighted voting. Through a detailed analysis of IMF Board discussions surrounding the Enhanced Structural Adjustment Facility (ESAF), this article sheds light on the mechanics of power in this often overlooked venue of global economic governance. By exploring the key issues of default liability and loan conditionality, I demonstrate that whilst the Boardroom is a more active site of contestation than has hitherto been recognized, material power is a prime determinant of both Executive Directors’ preferences and outcomes reached from discussions. And as the decisions reached form the backbone of the ‘instruction sheet’ used by Fund staff to guide their everyday operational decisions, these outcomes—and the processes through which they were reached—were factors of primary importance in stabilizing the operational norms at the heart of a controversial phase in the contemporary history of IMF concessional lending

    Critical perspectives on ‘consumer involvement’ in health research: epistemological dissonance and the know-do gap

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    Researchers in the area of health and social care (both in Australia and internationally) are encouraged to involve consumers throughout the research process, often on ethical, political and methodological grounds, or simply as ‘good practice’. This paper presents findings from a qualitative study in the UK of researchers’ experiences and views of consumer involvement in health research. Two main themes are presented in the paper. Firstly, we explore the ‘know-do gap’ which relates to the tensions between researchers’ perceptions of the potential benefits of, and their actual practices in relation to, consumer involvement. Secondly, we focus on one of the reasons for this ‘know-do gap’, namely epistemological dissonance. Findings are linked to issues around consumerism in research, lay/professional knowledges, the (re)production of professional and consumer identities and the maintenance of boundaries between consumers and researchers

    Limits on Gravitational-Wave Emission from Selected Pulsars Using LIGO Data

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    We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10^(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10^(-5) for the four closest pulsars
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