83 research outputs found

    Manipulating Pesticide Use to Increase the Production of Wild Game Birds in Britain

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    We describe a management technique whereby the adverse effects of pesticides on game-bird chick production were alleviated following selective use or selective avoidance of pesticides on the edges of cereal crops. This technique (known as Conservation Headlands) provided increased amounts of food resources necessary for young gray partridge (Perdix perdix) and ring-necked pheasant (Phasianus colchicus) chicks. The use of Conservation Headlands has consistently increased average numbers of chicks per brood of both species via increases in the densities of arthropods and weed plants. These findings are discussed in the context of the other prerequisites of wild game-bird production in the UK and how these may be altered by recent Government policies to reduce cereal surpluses

    SWCam: the short wavelength camera for the CCAT Observatory

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    We describe the Short Wavelength Camera (SWCam) for the CCAT observatory including the primary science drivers, the coupling of the science drivers to the instrument requirements, the resulting implementation of the design, and its performance expectations at first light. CCAT is a 25 m submillimeter telescope planned to operate at 5600 meters, near the summit of Cerro Chajnantor in the Atacama Desert in northern Chile. CCAT is designed to give a total wave front error of 12.5 μm rms, so that combined with its high and exceptionally dry site, the facility will provide unsurpassed point source sensitivity deep into the short submillimeter bands to wavelengths as short as the 200 μm telluric window. The SWCam system consists of 7 sub-cameras that address 4 different telluric windows: 4 subcameras at 350 μm, 1 at 450 μm, 1 at 850 μm, and 1 at 2 mm wavelength. Each sub-camera has a 6’ diameter field of view, so that the total instantaneous field of view for SWCam is equivalent to a 16’ diameter circle. Each focal plane is populated with near unit filling factor arrays of Lumped Element Kinetic Inductance Detectors (LEKIDs) with pixels scaled to subtend an solid angle of (λ/D)2 on the sky. The total pixel count is 57,160. We expect background limited performance at each wavelength, and to be able to map < 35(°)2 of sky to 5 σ on the confusion noise at each wavelength per year with this first light instrument. Our primary science goal is to resolve the Cosmic Far-IR Background (CIRB) in our four colors so that we may explore the star and galaxy formation history of the Universe extending to within 500 million years of the Big Bang. CCAT's large and high-accuracy aperture, its fast slewing speed, use of instruments with large format arrays, and being located at a superb site enables mapping speeds of up to three orders of magnitude larger than contemporary or near future facilities and makes it uniquely sensitive, especially in the short submm bands

    HI clouds in the proximity of M33

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    Neutral hydrogen clouds are found in the Milky Way and Andromeda halo both as large complexes and smaller isolated clouds. Here we present a search for Hi clouds in the halo of M33, the third spiral galaxy of the Local Group. We have used two complementary data sets: a 3^o x 3^o map of the area provided by the Arecibo Legacy Fast ALFA (ALFALFA) survey and deeper pointed observations carried out with the Arecibo telescope in two fields that permit sampling of the north eastern and south-western edges of the HI disc. The total amount of Hi around M33 detected by our survey is ∼107\sim 10^7 M⊙_{\odot}. At least 50% of this mass is made of HI clouds that are related both in space and velocity to the galaxy. We discuss several scenarios for the origin of these clouds focusing on the two most interesting ones: (a)(a) dark-matter dominated gaseous satellites, (b)(b) debris from filaments flowing into M33 from the intergalactic medium or generated by a previous interaction with M31. Both scenarios seem to fit with the observed cloud properties. Some structures are found at anomalous velocities, particularly an extended HI complex previously detected by Thilker et al. (2002). Even though the ALFALFA observations seem to indicate that this cloud is possibly connected to M33 by a faint gas bridge, we cannot firmly establish its extragalactic nature or its relation to M33. Taking into account that the clouds associated with M33 are likely to be highly ionised by the extragalactic UV radiation, we predict that the total gas mass associated with them is > 5 x 10^7 M⊙_{\odot}. If the gas is steadily falling towards the M33 disc it can provide the fuel needed to sustain a current star formation rate of 0.5 M⊙_{\odot} yr−1^{-1}.Comment: 16 pages, 19 figures. Accepted for publication in A&

    The magnetic field in the Flame nebula

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    Star formation is essential in galaxy evolution and the cycling of matter. The support of interstellar clouds against gravitational collapse by magnetic (B-) fields has been proposed to explain the low observed star formation efficiency in galaxies and the Milky Way. Despite the Planck satellite providing a 5-15' all-sky map of the B-field geometry in the diffuse interstellar medium, higher spatial resolution observations are required to understand the transition from diffuse gas to gravitationally unstable filaments. NGC 2024, the Flame Nebula, in the nearby Orion B molecular cloud, contains a young, expanding HII region and a dense filament that harbors embedded protostellar objects. Therefore, NGC 2024 is an excellent opportunity to study the role of B-fields in the formation, evolution, and collapse of filaments, as well as the dynamics and effects of young HII regions on the surrounding molecular gas. We combine new 154 and 216 micron dust polarization measurements carried out using the HAWC+ instrument aboard SOFIA with molecular line observations of 12CN(1-0) and HCO+(1-0) from the IRAM 30-meter telescope to determine the B-field geometry and to estimate the plane of the sky magnetic field strength across the NGC 2024. The HAWC+ observations show an ordered B-field geometry in NGC 2024 that follows the morphology of the expanding HII region and the direction of the main filament. The derived plane of the sky B-field strength is moderate, ranging from 30 to 80 micro G. The strongest B-field is found at the northern-west edge of the HII region, characterized by the highest gas densities and molecular line widths. In contrast, the weakest field is found toward the filament in NGC 2024. The B-field has a non-negligible influence on the gas stability at the edges of the expanding HII shell (gas impacted by the stellar feedback) and the filament (site of the current star formation).Comment: 36 pages, 26 figures Accepted for publication in Astronomy & Astrophysic

    The impact of sex on severe asthma: a cross-sectional retrospective analysis of UK primary and specialist care:a cross-sectional retrospective analysis of UK primary and specialist care

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    After puberty, females are more likely to develop asthma and in a more severe form than males. The associations between asthma and sex are complex with multiple intrinsic and external factors. To evaluate the sex differences in the characteristics and treatment of patients with severe asthma (SA) in a real-world setting. Demographic, clinical and treatment characteristics for patients with SA in the UK Severe Asthma Registry (UKSAR) and Optimum Patient Care Research Database (OPCRD) were retrospectively analysed by sex using univariable and multivariable logistic regression analyses adjusted for year, age and hospital/practice. 3679 (60.9% female) patients from UKSAR and 18 369 patients (67.9% female) from OPCRD with SA were included. Females were more likely to be symptomatic with increased Asthma Control Questionnaire-6 (UKSAR adjusted OR (aOR) 1.14, 95% CI 1.09 to 1.18) and Royal College of Physicians-3 Question scores (OPCRD aOR 1.29, 95% CI 1.13 to 1.47). However, they had a higher forced expiratory volume in 1 second per cent (FEV %) predicted (UKSAR 68.7% vs 64.8%,

    SWCam: the short wavelength camera for the CCAT Observatory

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    We describe the Short Wavelength Camera (SWCam) for the CCAT observatory including the primary science drivers, the coupling of the science drivers to the instrument requirements, the resulting implementation of the design, and its performance expectations at first light. CCAT is a 25 m submillimeter telescope planned to operate at 5600 meters, near the summit of Cerro Chajnantor in the Atacama Desert in northern Chile. CCAT is designed to give a total wave front error of 12.5 μm rms, so that combined with its high and exceptionally dry site, the facility will provide unsurpassed point source sensitivity deep into the short submillimeter bands to wavelengths as short as the 200 μm telluric window. The SWCam system consists of 7 sub-cameras that address 4 different telluric windows: 4 subcameras at 350 μm, 1 at 450 μm, 1 at 850 μm, and 1 at 2 mm wavelength. Each sub-camera has a 6’ diameter field of view, so that the total instantaneous field of view for SWCam is equivalent to a 16’ diameter circle. Each focal plane is populated with near unit filling factor arrays of Lumped Element Kinetic Inductance Detectors (LEKIDs) with pixels scaled to subtend an solid angle of (λ/D)2 on the sky. The total pixel count is 57,160. We expect background limited performance at each wavelength, and to be able to map < 35(°)2 of sky to 5 σ on the confusion noise at each wavelength per year with this first light instrument. Our primary science goal is to resolve the Cosmic Far-IR Background (CIRB) in our four colors so that we may explore the star and galaxy formation history of the Universe extending to within 500 million years of the Big Bang. CCAT's large and high-accuracy aperture, its fast slewing speed, use of instruments with large format arrays, and being located at a superb site enables mapping speeds of up to three orders of magnitude larger than contemporary or near future facilities and makes it uniquely sensitive, especially in the short submm bands

    A qualitative study of cardiac rehabilitation patients’ perspectives on taking medicines: implications for the ‘medicines-resistance’ model of medicine-taking

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    Background The appropriate use of medicines continues to be an important area of inter-disciplinary research activity both in the UK and beyond. Key qualitative work in this area in the last decade has included the ‘medicines resistance’ model of medicine-taking, which was based on a meta-ethnography of 37 qualitative studies. This model proposed that patients approach medicine-taking as ‘passive accepters’, ‘active accepters’, ‘active modifiers’ or ‘complete rejecters’, of which the latter two categories were considered to show ‘resistance’ to medicines. However, critical assessment of the model appears to be currently lacking, particularly in terms of its use in clinical practice. This paper seeks to contribute to the literature in this area by critically examining the practical application of the model in light of the findings from a qualitative, follow-up study of cardiac rehabilitation patients’ perspectives and experiences of using medicines. Methods Following ethical approval, in-depth, audiotaped, qualitative interviews were conducted with fifteen patients who had completed a UK hospital-based cardiac rehabilitation programme. Participants were aged 42–65, white British and from a variety of socioeconomic backgrounds. Interview topics included perspectives on coronary heart disease, medicine-taking and lifestyle changes. Follow-up interviews with ten patients approximately nine months later explored whether their perspectives had changed. Results The findings suggest that the active/passive and accepter/modifier distinctions may not allow for clear determination of which profile a patient fits into at any given point, and that definitions such as ‘accepter’ and ‘resistance’ may be insufficiently discerning to categorise patients’ use of medicines in practice. These problems appear to arise when the issue of patients’ accounts about medicines adherence are considered, since patients may have concerns or disquiet about medicines whether or not they are adherent and the model does not consider disquiet in isolation from adherence. Conclusions Practical application of the ‘medicines resistance’ model of medicine-taking may be problematic in this patient group. Dissociation of disquiet about medicines from medicines adherence may allow for a focus on helping patients to resolve their disquiet, if possible, without this necessarily having to be viewed in terms of its potential effect on adherence

    BrAPI-an application programming interface for plant breeding applications

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    Motivation: Modern genomic breeding methods rely heavily on very large amounts of phenotyping and genotyping data, presenting new challenges in effective data management and integration. Recently, the size and complexity of datasets have increased significantly, with the result that data are often stored on multiple systems. As analyses of interest increasingly require aggregation of datasets from diverse sources, data exchange between disparate systems becomes a challenge. Results: To facilitate interoperability among breeding applications, we present the public plant Breeding Application Programming Interface (BrAPI). BrAPI is a standardized web service API specification. The development of BrAPI is a collaborative, community-based initiative involving a growing global community of over a hundred participants representing several dozen institutions and companies. Development of such a standard is recognized as critical to a number of important large breeding system initiatives as a foundational technology. The focus of the first version of the API is on providing services for connecting systems and retrieving basic breeding data including germplasm, study, observation, and marker data. A number of BrAPI-enabled applications, termed BrAPPs, have been written, that take advantage of the emerging support of BrAPI by many databases
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