3,018 research outputs found
Finding bright <i>z</i> ā„ 6.6 Ly <i>Ī±</i> emitters with lensing: prospects for <i>Euclid</i>
We model the Ly luminosity function to estimate the
number of lensed high Ly emitters that may be detected by the
Euclid Deep Survey. To span the whole range of possible predictions we exploit
two Ly luminosity function models and two strong gravitational lensing
models from the literature. We show that the planned Euclid Deep Survey
observing 40 deg over the 920-1850 nm wavelength range down to a flux limit
of erg scm will enable us to find
between and deg lensed Ly emitters at depending on the adopted Ly luminosity function and strong
gravitational lensing model. The obvious [OII], [OIII] and H
contaminants of the Ly lensed population will be identified with the
help of Euclid's spectral resolving power, while the SKA will enable the
identification of the interloper population of H emitters. By combining
Euclid and the SKA, we will thus be able to identify, for the first time, a
sample of to lensed Ly emitters at .Comment: Accepted for publication in MNRAS on 20 June 2017. (NEW: Amended
Latex
High-intensity interval training: optimizing oxygen consumption and time to exhaustion taking advantage of the exponential reconstitution behaviour of Dā
Purpose: Accumulating the time near maximum aerobic power (V Ė O 2max) is considered to be the most effective way to improve aerobic capacity. The aims of this study were: (1) to verify whether postponing the first recovery interval improves time to exhaustion during a high-intensity interval training (HIIT) test, and (2) to verify whether a HIIT protocol with decreasing interval duration (HIDIT) is more effective in accumulating time near V Ė O 2max compared with two classical protocols with short intervals (SIHIIT) and long intervals (LIHIIT). Methods: Nine active males (35 Ā± 11Ā years, V Ė O 2max 52 Ā± 5Ā mLĀ·minā1Ā·kgā1) performed a graded exercise test on an athletic track. Critical velocity and Dā were estimated from three to five high-intensity trials to exhaustion. Then, the subjects performed three trials with a single recovery interval after 30Ā s (Rec30s), after 3Ā min (Rec3min) and after exhaustion (RecTlim) to verify whether postponing the first recovery interval enhances the time to exhaustion. Finally, the subjects performed the three HIIT protocols mentioned above. Results: The time to exhaustion was significantly greater in RecTlim (464 Ā± 67Ā s) than in Rec3min (388 Ā± 48Ā s) (p 0.0001). Additionally, it was significantly greater in Rec3min than in Rec30s (p = 0.0247). Furthermore, the time accumulated near V Ė O 2max was significantly longer in HIDIT (998 Ā± 129Ā s) than in SIHIIT (678 Ā± 116Ā s) (p = 0.003) and LIHIIT (673 Ā± 115Ā s) (p < 0.031). Conclusions: During the trials, postponing the first recovery interval was effective in improving the time to exhaustion. Moreover, HIDIT was effective in prolonging the time near V Ė O 2max
The Stripe 82 1-2 GHz Very Large Array Snapshot Survey: Multiwavelength Counterparts
We have combined spectrosopic and photometric data from the Sloan Digital Sky
Survey (SDSS) with GHz radio observations, conducted as part of the
Stripe 82 GHz Snapshot Survey using the Karl G. Jansky Very Large Array
(VLA), which covers sq degrees, to a flux limit of 88 Jy rms.
Cross-matching the radio source components with optical data via
visual inspection results in a final sample of cross-matched objects,
of which have spectroscopic redshifts and objects have
photometric redshifts. Three previously undiscovered Giant Radio Galaxies
(GRGs) were found during the cross-matching process, which would have been
missed using automated techniques. For the objects with spectroscopy we
separate radio-loud Active Galactic Nuclei (AGN) and star-forming galaxies
(SFGs) using three diagnostics and then further divide our radio-loud AGN into
the HERG and LERG populations. A control matched sample of HERGs and LERGs,
matched on stellar mass, redshift and radio luminosity, reveals that the host
galaxies of LERGs are redder and more concentrated than HERGs. By combining
with near-infrared data, we demonstrate that LERGs also follow a tight
relationship. These results imply the LERG population are hosted by population
of massive, passively evolving early-type galaxies. We go on to show that
HERGs, LERGs, QSOs and star-forming galaxies in our sample all reside in
different regions of a WISE colour-colour diagram. This cross-matched sample
bridges the gap between previous `wide but shallow' and `deep but narrow'
samples and will be useful for a number of future investigations.Comment: 17 pages, 19 figures. Resubmitted to MNRAS after the initial comment
Fe(II) and Mn(II) removal from contaminated groundwater by adsorption. A comparison of activated carbon and pine bark
This paper aims to compare the adsorption performance of activated carbon and pine bark for iron and manganese removal from contaminated groundwater. Moreover, their environmental compatibility was checked for their possible use as reactive media in a permeable reactive barrier for in situ remediation. Batch tests were carried out with different iron and manganese concentrations and different particle-size distributions, in order to evaluate the effectiveness of the activated carbon and pine bark on removal depending on both the initial pollutant concentration and the surface area of the adsorbent. High removal efficiencies were reached by both of the reactive media. However, faster removal at higher concentration was observed only for iron adsorption by activated carbon. The particle-size distribution did not significantly influence the process in the experimental conditions tested. The immobilization process on the reactive media can be considered almost irreversible since the quantities of iron and manganese released during the desorption tests were negligible
Global Opportunities to Increase Agricultural Independence Through Phosphorus Recycling
Food production hinges largely upon access to phosphorus (P) fertilizer. Most fertilizer P used in the global agricultural system comes from mining of nonrenewable phosphate rock deposits located within few countries. However, P contained in livestock manure or urban wastes represents a recyclable source of P. To inform development of P recycling technologies and policies, we examined subnational, national, and global spatial patterns for two intersections of land use affording high P recycling potential: (a) manureārich cultivated areas and (b) populous cultivated areas. In turn, we examined overlap between P recycling potential and nationālevel P fertilizer import dependency. Populous cultivated areas were less abundant globally than manureārich cultivated areas, reflecting greater segregation between crops and people compared to crops and livestock, especially in the Americas. Based on a global hexagonal grid (290ākm2 grid cell area), disproportionately large shares of subnational āhot spotsā for P recycling potential occurred in India, China, Southeast Asia, Europe, and parts of Africa. Outside of China, most of the remaining manureārich or populous cultivated areas occurred within nations that had relatively high imports of P fertilizer (net P import:consumption ratios ā„0.4) or substantial increases in fertilizer demand between the 2000s (2002ā2006) and 2010s (2010ā2014). Manureārich cultivated grid cells (those above the 75th percentiles for both manure and cropland extent) represented 12% of the global grid after excluding cropless cells. Annually, the global sum of animal manure P was at least 5 times that contained in human excreta, and among cultivated cells the ratio was frequently higher (median = 8.9). The abundance of potential P recycling hot spots within nations that have depended on fertilizer imports or experienced rising fertilizer demand could prove useful for developing local P sources and maintaining agricultural independence
Accidental exposure to politics on social media as online participation equalizer in Germany, Italy, and the United Kingdom
We assess whether and how accidental exposure to political information on social
media contributes to citizens\u2019 online political participation in comparative perspective.
Based on three online surveys of samples representative of German, Italian, and British
Internet users in the aftermath of the 2014 European Parliament elections, we find that
accidental exposure to political information on social media is positively and significantly
correlated with online participation in all three countries, particularly so in Germany
where overall levels of participation were lower. We also find that interest in politics
moderates this relationship so that the correlation is stronger among the less interested
than among the highly interested. These findings suggest that inadvertent encounters
with political content on social media are likely to reduce the gap in online engagement
between citizens with high and low interest in politics, potentially broadening the range
of voices that make themselves heard
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