1,314 research outputs found

    Breakfast Dietary Patterns among Mexican Children Are Related to Total-Day Diet Quality

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    Background: Mexico has experienced shifts in food availability and consumption patterns over the past few decades from traditional diets to those containing more high-energy density foods, resulting in the development of unhealthful dietary patterns among children and adults. However, to our knowledge it is not known whether breakfast consumption patterns contribute to the overall daily diet of Mexican children.Objective: We examined total-day diet among breakfast consumers compared with breakfast skippers, identified and investigated breakfast dietary patterns in relation to energy and nutrient intakes at breakfast and across the day, and examined these patterns in relation to sociodemographic characteristics.Methods: With the use of nationally representative dietary data (one 24-h recall) from the 2012 Mexican National Health and Nutrition Survey, 3760 children aged 4-13 y were categorized into mutually exclusive breakfast patterns with the use of cluster analysis. The association between breakfast patterns and breakfast skippers with dietary intake at breakfast and for the total day was investigated with the use of multivariate linear regression.Results: Most children (83%) consumed breakfast. Six breakfast dietary patterns were identified (milk and sweetened breads, tortillas and beans, sweetened beverages, sandwiches and quesadillas, eggs, and cereal and milk) and reflected both traditional and more Westernized dietary patterns. Sugar-sweetened beverages were consumed across all patterns. Compared with all breakfast dietary patterns, breakfast skippers had the lowest intake of several nutrients of public health concern. Nutrients to limit that were high at breakfast tended to be high for the total day and vice versa for nutrients to encourage.Conclusions: There was not a single pattern that complied perfectly with the Mexican School Breakfast Guidelines, but changes such as increasing dietary fiber by encouraging more whole grains, fruits, vegetables, and beans and reducing sodium and sugar-sweetened beverages could support compliance with these targets and improve overall diet quality

    The Spatial Clustering of ROSAT All-Sky Survey AGNs II. Halo Occupation Distribution Modeling of the Cross Correlation Function

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    This is the second paper of a series that reports on our investigation of the clustering properties of AGNs in the ROSAT All-Sky Survey (RASS) through cross-correlation functions (CCFs) with Sloan Digital Sky Survey (SDSS) galaxies. In this paper, we apply the Halo Occupation Distribution (HOD) model to the CCFs between the RASS Broad-line AGNs with SDSS Luminous Red Galaxies (LRGs) in the redshift range 0.16<z<0.36 that was calculated in paper I. In our HOD modeling approach, we use the known HOD of LRGs and constrain the HOD of the AGNs by a model fit to the CCF. For the first time, we are able to go beyond quoting merely a `typical' AGN host halo mass, M_h, and model the full distribution function of AGN host dark matter halos. In addition, we are able to determine the large-scale bias and the mean M_h more accurately. We explore the behavior of three simple HOD models. Our first model (Model A) is a truncated power-law HOD model in which all AGNs are satellites. With this model, we find an upper limit to the slope (\alpha) of the AGN HOD that is far below unity. The other two models have a central component, which has a step function form, where the HOD is constant above a minimum mass, without (Model B) or with (Model C) an upper mass cutoff, in addition to the truncated power-law satellite component, similar to the HOD that is found for galaxies. In these two models we find the upper limits of \alpha < 0.95 and \alpha < 0.84 for Model B and C respectively. Our analysis suggests that the satellite AGN occupation increases slower than, or may even decrease with, M_h, in contrast to the satellite's HODs of luminosity-threshold samples of galaxies, which, in contrast, grow approximately as \propto M_h^\alpha with \alpha\approx 1. These results are consistent with observations that the AGN fraction in groups and clusters decreases with richness.Comment: 15 pages, 9 figures. ApJ in pres

    The physical scale of the far-infrared emission in the most luminous submillimetre galaxies II: evidence for merger-driven star formation

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    We present high-resolution 345 GHz interferometric observations of two extreme luminous (L_{IR}>10^{13} L_sun), submillimetre-selected galaxies (SMGs) in the COSMOS field with the Submillimeter Array (SMA). Both targets were previously detected as unresolved point-sources by the SMA in its compact configuration, also at 345 GHz. These new data, which provide a factor of ~3 improvement in resolution, allow us to measure the physical scale of the far-infrared in the submillimetre directly. The visibility functions of both targets show significant evidence for structure on 0.5-1 arcsec scales, which at z=1.5 translates into a physical scale of 5-8 kpc. Our results are consistent with the angular and physical scales of two comparably luminous objects with high-resolution SMA followup, as well as radio continuum and CO sizes. These relatively compact sizes (<5-10 kpc) argue strongly for merger-driven starbursts, rather than extended gas-rich disks, as the preferred channel for forming SMGs. For the most luminous objects, the derived sizes may also have important physical consequences; under a series of simplifying assumptions, we find that these two objects in particular are forming stars close to or at the Eddington limit for a starburst.Comment: 9 pages, 3 Figures, submitted to MNRA

    Calibrating the Star Formation Rate at z=1 from Optical Data

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    We present a star-formation rate calibration based on optical data that is consistent with average observed rates in both the red and blue galaxy populations at z~1. The motivation for this study is to calculate SFRs for DEEP2 Redshift Survey galaxies in the 0.7<z<1.4 redshift range, but our results are generally applicable to similar optically-selected galaxy samples without requiring UV or IR data. Using SFRs fit from UV/optical SEDs in the AEGIS survey, we explore the behavior of restframe B-band magnitude, observed [OII] luminosity, and restframe (U-B) color with SED-fit SFR for both red sequence and blue cloud galaxies. We find that a SFR calibration can be calculated for all z~1 DEEP2 galaxies using a simultaneous fit in M_B and restframe colors with residual errors that are within the SFR measurement error. The resulting SFR calibration produces fit residual errors of 0.3 dex RMS scatter for the full color-independent sample with minimal correlated residual error in L[OII] or stellar mass. We then compare the calibrated z~1 SFRs to two diagnostics that use L[OII] as a tracer in local galaxies and correct for dust extinction at intermediate redshifts through either galaxy B-band luminosity or stellar mass. We find that a L[OII] - M_B SFR calibration commonly used in the literature agrees well with our calculated SFRs after correcting for the average B-band luminosity evolution in L* galaxies. However, we find better agreement with a local L[OII]-based SFR calibration that includes stellar mass to correct for reddening effects, indicating that stellar mass is a better tracer of dust extinction for all galaxy types and less affected by systematic evolution than galaxy luminosity from z=1 to the current epoch.Comment: 16 pages, 15 figures, emulateapj format, to be submitted to Ap

    The Persistence of Cool Galactic Winds in High Stellar Mass Galaxies Between z~1.4 and ~1

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    We present an analysis of the MgII 2796, 2803 and FeII 2586, 2600 absorption line profiles in coadded spectra of 468 galaxies at 0.7 < z < 1.5. The galaxy sample, drawn from the Team Keck Treasury Redshift Survey of the GOODS-N field, has a range in stellar mass (M_*) comparable to that of the sample at z~1.4 analyzed in a similar manner by Weiner et al. (2009; W09), but extends to lower redshifts and has specific star formation rates which are lower by ~0.6 dex. We identify outflows of cool gas from the Doppler shift of the MgII absorption lines and find that the equivalent width (EW) of absorption due to outflowing gas increases on average with M_* and star formation rate (SFR). We attribute the large EWs measured in spectra of the more massive, higher-SFR galaxies to optically thick absorbing clouds having large velocity widths. The outflows have hydrogen column densities N(H) > 10^19.3 cm^-2, and extend to velocities of ~500 km/s. While galaxies with SFR > 10 Msun/yr host strong outflows in both this and the W09 sample, we do not detect outflows in lower-SFR (i.e., log M_*/Msun < 10.5) galaxies at lower redshifts. Using a simple galaxy evolution model which assumes exponentially declining SFRs, we infer that strong outflows persist in galaxies with log M_*/Msun > 10.5 as they age between z=1.4 and z~1, presumably because of their high absolute SFRs. Finally, using high resolution HST/ACS imaging in tandem with our spectral analysis, we find evidence for a weak trend (at 1 sigma significance) of increasing outflow absorption strength with increasing galaxy SFR surface density.Comment: Submitted to ApJ. 25 pages, 19 figures, Figure 2 reduced in resolution. Uses emulateapj forma

    A pilot study investigating the effects of a manuka honey sinus rinse compared to a standard sinus rinse on sino-nasal outcome test scores in cystic fibrosis patients

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    Background: People with cystic fibrosis (CF) are prone to bacterial respiratory infections; these are often antibiotic resistant, are difficult to treat, and impact on the quality of life and lung function. The upper respiratory tract can act as a reservoir for these pathogens, and as part of clinical care, sinus rinses are used to alleviate symptoms in the upper airway. We have developed a sinus rinse containing manuka honey, to identify whether it can help improve symptoms or reduce the bacterial load. Methods: We will undertake a randomised controlled trial where 30 adults with CF will be recruited and randomised to either the control or intervention group. Both groups will follow a sinus rinse protocol for 30 days (± 7 days); the control group will use the standard of care rinse, and the intervention group will use a manuka honey rinse. Both groups will provide samples at day 0 and day 30. The primary outcome measure will be a change in the 22-item Sino-Nasal Outcome Test (SNOT-22) score. Secondary outcomes will include changes to quality of life (questionnaire), bacterial load/community composition, and sputum viscosity. Discussion: This trial will look at the use of a manuka honey-infused sinus rinse solution on patients diagnosed with cystic fibrosis (CF) suffering with sinusitis; it will allow us to determine the efficacy of the manuka honey sinus rinse compared to standard rinse and will allow us to determine if molecular bacterial diversity analysis will provide in-depth information beyond the usual conventional microbiological. It will allow us to determine the feasibility of recruiting participants to this type of trial, allow us to check participant compliance with the protocol, and inform future studies. Trial registration: Approval was obtained from the Research Ethics Committee Wales REC7 reference 18/WA/0319. Results of this study will be published at international conferences and in peer-reviewed journals; they will also be presented to the relevant stakeholders and research networks

    Effect of ocean acidification and elevated fCO2 on trace gas production from the Baltic Sea summer phytoplankton community.

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    The Baltic Sea is a unique environment as the largest body of brackish water in the world. Acidification of the surface oceans due to absorption of anthropogenic CO2 emissions is an additional stressor facing the pelagic community of the already challenging Baltic Sea. To investigate its impact on trace gas biogeochemistry, a large-scale mesocosm experiment was performed off Tvärminne Research Station, Finland, in summer 2012. During the second half of the experiment, dimethylsulfide (DMS) concentrations in the highest-fCO2 mesocosms (1075–1333 µatm) were 34 % lower than at ambient CO2 (350 µatm). However, the net production (as measured by concentration change) of seven halocarbons analysed was not significantly affected by even the highest CO2 levels after 5 weeks' exposure. Methyl iodide (CH3I) and diiodomethane (CH2I2) showed 15 and 57 % increases in mean mesocosm concentration (3.8 ± 0.6 increasing to 4.3 ± 0.4 pmol L−1 and 87.4 ± 14.9 increasing to 134.4 ± 24.1 pmol L−1 respectively) during Phase II of the experiment, which were unrelated to CO2 and corresponded to 30 % lower Chl a concentrations compared to Phase I. No other iodocarbons increased or showed a peak, with mean chloroiodomethane (CH2ClI) concentrations measured at 5.3 (±0.9) pmol L−1 and iodoethane (C2H5I) at 0.5 (±0.1) pmol L−1. Of the concentrations of bromoform (CHBr3; mean 88.1 ± 13.2 pmol L−1), dibromomethane (CH2Br2; mean 5.3 ± 0.8 pmol L−1), and dibromochloromethane (CHBr2Cl, mean 3.0 ± 0.5 pmol L−1), only CH2Br2 showed a decrease of 17 % between Phases I and II, with CHBr3 and CHBr2Cl showing similar mean concentrations in both phases. Outside the mesocosms, an upwelling event was responsible for bringing colder, high-CO2, low-pH water to the surface starting on day t16 of the experiment; this variable CO2 system with frequent upwelling events implies that the community of the Baltic Sea is acclimated to regular significant declines in pH caused by up to 800 µatm fCO2. After this upwelling, DMS concentrations declined, but halocarbon concentrations remained similar or increased compared to measurements prior to the change in conditions. Based on our findings, with future acidification of Baltic Sea waters, biogenic halocarbon emissions are likely to remain at similar values to today; however, emissions of biogenic sulfur could significantly decrease in this region

    Sheep Updates 2008 - part 2

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    This session covers eleven papers from different authors: The Sheep Room 1. Analgesia for Surgical Husbandry Procedures in Sheep and Other Livestock, Dr Meredith L. Sheil, Animal Ethics Pty Ltd, Associate Sydney University Faculty of Veterinary Science The Wool Enterprise 2. Unmulsed sheep - implications for chemical use, Di Evans & Brown Besier, Department of Agriculture and Food WA 3. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Growth rates, Tim Scanlon1, Andre Martinho de Almeida2, Johan Greeff1, Tanya Kilminster1, John Milton3, Chris Oldham1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, Lisbon, Portugal2, University of Western Australia3 4. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Carcass attributes, Tanya Kilminster1, Andre Martinho de Almeida2, Johan Greeff1, John Milton3, Chris Oldham1, Tim Scanlon1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, Lisbon, Portugal2, University of Western Australia3 The Beef Room 5. Benefits of matching animal requirements with pasture feed supply and animal supply market requirements, B.L. McIntyre, Department of Agriculture and Food Western Australia, 6. Optimal grazing for beef, Alison Wheatley, Beef farmer Winnejup, John Lucey, Department of Agriculture and Food, Western Australia 7. Grain Introduction in commercial cattle feedlots, Fiona Jones1,2, Nick Costa2, 1 Department of Agriculture and Food WA and 2 Murdoch University. Mixed Systems 8. Confinement feeding stock in mixed enterprises, John Milton, The University of Western Australia & Independent Lab Services The Sheep Enterprise 9. Making More than Sheep, Ed Riggall, Australian Wool Innovation and Meat & Livestock Australia 10. Sheep Cost of Production - the enemy is at the gate!, JRL (Bob) Hall, JRL Hall & Co 11. Australian lamb - high yielding good to eat, Robin Jacob1, Dave Pethick2, Dave Hopkins3 and Graham Gardner2, 1Department of Agrcultre and Food WA, 2Murdoch University, 3NSW Department of Primary Industrie

    Variability and Multiwavelength Detected AGN in the GOODS Fields

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    We identify 85 variable galaxies in the GOODS North and South fields using 5 epochs of HST ACS V-band (F606W) images spanning 6 months. The variables are identified through significant flux changes in the galaxy's nucleus and represent ~2% of the survey galaxies. With the aim of studying the active galaxy population in the GOODS fields, we compare the variability-selected sample with X-ray and mid-IR AGN candidates. Forty-nine percent of the variables are associated with X-ray sources identified in the 2Ms Chandra surveys. Twenty-four percent of X-ray sources likely to be AGN are optical variables and this percentage increases with decreasing hardness ratio of the X-ray emission. Stacking of the non-X-ray detected variables reveals marginally significant soft X-ray emission. Forty-eight percent of mid-IR power-law sources are optical variables, all but one of which are also X-ray detected. Thus, about half of the optical variables are associated with either X-ray or mid-IR power-law emission. The slope of the power-law fit through the Spitzer IRAC bands indicates that two-thirds of the variables have BLAGN-like SEDs. Among those galaxies spectroscopically identified as AGN, we observe variability in 74% of broad-line AGNs and 15% of NLAGNs. The variables are found in galaxies extending to z~3.6. We compare the variable galaxy colors and magnitudes to the X-ray and mid-IR sample and find that the non-X-ray detected variable hosts extend to bluer colors and fainter intrinsic magnitudes. The variable AGN candidates have Eddington ratios similar to those of X-ray selected AGN.Comment: 36 pages, 12 figures, ApJ accepte

    The Co-Formation of Spheroids and Quasars Traced in their Clustering

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    We compare observed clustering of quasars and galaxies as a function of redshift, mass, luminosity, & color/morphology, to constrain models of quasar fueling and spheroid-BH co-evolution. High redshift quasars are shown to be drawn from progenitors of local early-type galaxies, with the characteristic quasar luminosity L* reflecting a characteristic mass of 'active' BH/host populations at each redshift. Evolving observed high-z quasar clustering to z=0 predicts a trend of clustering in 'quasar remnants' as a function of stellar mass identical to that observed for early-types. However, quasar clustering does not simply reflect observed early (or late)-type populations; at each redshift, quasars cluster as an 'intermediate' population. Comparing with the age of elliptical stellar populations reveals that this 'intermediate' population represents those ellipticals undergoing or terminating their final significant star formation at each epoch. Assuming that quasar triggering is associated with the formation/termination epoch of ellipticals predicts quasar clustering at all observed redshifts without any model dependence or assumptions about quasar light curves, lifetimes, or accretion rates. This is not true for disks or quasar halos: i.e. quasars do not generically trace star formation, disks, or halo assembly. Quasar clustering at all z is consistent with a constant halo mass ~4x10^{12} M_sun, similar to local 'group scales.' The observations support a scenario in which major mergers trigger quasar activity and dominate bright, high-z quasar populations. We show that measurements of quasar clustering versus luminosity at z~1 can be used to constrain different lower-luminosity AGN fueling mechanisms, and that high-z clustering is sensitive to whether or not systems 'shut down' growth at z>3.Comment: 21 pages, 14 figures. Accepted to ApJ. Minor revisions to match published versio
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