14,159 research outputs found

    An Unbiassed Census of Active Galactic Nuclei in the Two Micron All Sky Survey

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    (Abridged) We present an unbiassed near-IR selected AGN sample, covering 12.56 square degrees down to K ~ 15.5, selected from the Two Micron All Sky Survey (2MASS). Our only selection effect is a moderate color cut (J-K>1.2) designed to reduce contamination from galactic stars. We observed both point-like and extended sources. Using the brute-force capabilities of the 2dF multi-fiber spectrograph on the Anglo-Australian Telescope, we obtained spectra of 65% of the target list: an unbiassed sub-sample of 1526 sources. 80% of the 2MASS sources in our fields are galaxies, with a median redshift of 0.15. The remainder are K- and M-dwarf stars. Seyfert-2 Galaxies are roughly three times more common in this sample than in optically selected galaxy samples (once corrections have been made for the equivalent width limit and for different aperture sizes). We find 14 broad-line (Type-1) AGNs, giving a surface density down to K<15 comparable to that of optical samples down to B=18.5. Half of our Type-1 AGNs could not have been found by normal color selection techniques. In all cases this was due host galaxy light contamination rather than intrinsically red colors. We conclude that the Type-1 AGN population found in the near-IR is not dramatically different from that found in optical samples. There is no evidence for a large population of AGNs that could not be found at optical wavelengths, though we can only place very weak constraints on any population of dusty high-redshift QSOs.Comment: AJ in pres

    An Unbiassed Census of Active Galactic Nuclei in the Two Micron All Sky Survey

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    (Abridged) We present an unbiassed near-IR selected AGN sample, covering 12.56 square degrees down to K ~ 15.5, selected from the Two Micron All Sky Survey (2MASS). Our only selection effect is a moderate color cut (J-K>1.2) designed to reduce contamination from galactic stars. We observed both point-like and extended sources. Using the brute-force capabilities of the 2dF multi-fiber spectrograph on the Anglo-Australian Telescope, we obtained spectra of 65% of the target list: an unbiassed sub-sample of 1526 sources. 80% of the 2MASS sources in our fields are galaxies, with a median redshift of 0.15. The remainder are K- and M-dwarf stars. Seyfert-2 Galaxies are roughly three times more common in this sample than in optically selected galaxy samples (once corrections have been made for the equivalent width limit and for different aperture sizes). We find 14 broad-line (Type-1) AGNs, giving a surface density down to K<15 comparable to that of optical samples down to B=18.5. Half of our Type-1 AGNs could not have been found by normal color selection techniques. In all cases this was due host galaxy light contamination rather than intrinsically red colors. We conclude that the Type-1 AGN population found in the near-IR is not dramatically different from that found in optical samples. There is no evidence for a large population of AGNs that could not be found at optical wavelengths, though we can only place very weak constraints on any population of dusty high-redshift QSOs.Comment: AJ in pres

    Building consensus on interactions between population health researchers and the food industry: two-stage, online, international Delphi study and stakeholder survey

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    Abstract Key to scientific integrity is ensuring that research findings are considered credible by scientific peers, practitioners, policymakers and the public. Industry sponsorship of nutritional research can result in bias and raises significant professional, public and media concern. Yet, there is no international consensus on how to prevent or manage conflicts of interest for researchers considering engaging with the food industry. This study aimed to determine internationally agreed principles to guide interactions between population health researchers and the food industry to prevent or manage conflicts of interest. We used a two-stage, online Delphi study for researchers (n=100 in 28 countries), and an online survey for stakeholders (n=84 in 26 countries). Levels of agreement were sought with 56 principles derived from a systematic review. Respondent comments were analysed using qualitative content analysis. High levels of agreement on principles were achieved for both groups (researchers 68%; stakeholders 65%). Highest levels of agreement were with principles concerning research methods and governance. More contentious were principles that required values-based decision-making, such as determining which elements of the commercial sector are acceptable to interact with. These results provide the basis for developing internationally-agreed guidelines for population health researchers governing interactions with the food industry.The work was undertaken under the auspices of the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence which is funded by the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the National Institute for Health Research, and the Wellcome Trust

    Registration of Ten Sorghum Parental Lines

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    The Nebraska Agric. Exp. Stn. and AR-SEA-USDA released in January 1980 10 pairs of A and B (male-sterile and maintainer) Sorghum bicolor (L.) Moench inbred lines for producing grain and forage sorghum hybrids. All A-lines have milo cytoplasm

    Registration of Ten Sorghum Parental Lines

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    The Nebraska Agric. Exp. Stn. and AR-SEA-USDA released in January 1980 10 pairs of A and B (male-sterile and maintainer) Sorghum bicolor (L.) Moench inbred lines for producing grain and forage sorghum hybrids. All A-lines have milo cytoplasm

    Registration of Ten Sorghum Parental Lines

    Get PDF
    The Nebraska Agric. Exp. Stn. and AR-SEA-USDA released in January 1980 10 pairs of A and B (male-sterile and maintainer) Sorghum bicolor (L.) Moench inbred lines for producing grain and forage sorghum hybrids. All A-lines have milo cytoplasm

    Comparative analyses of the feasibility of cooling and LPS methods of milk preservation

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