264 research outputs found
Evolution of faint radio sources in the VIDEO-XMM3 field
© 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical SocietyIt has been speculated that low-luminosity radio-loud active galactic nuclei (AGN) have the potential to serve as an important source of AGN feedback, and may be responsible for suppressing star formation activity in massive elliptical galaxies at late times. As such the cosmic evolution of these sources is vitally important to understand the significance of such AGN feedback processes and their influence on the global star formation history of the Universe. In this paper, we present a new investigation of the evolution of faint radio sources out to z ~ 2.5. We combine a 1 square degree Very Large Array radio survey, complete to a depth of 100 μJy, with accurate 10 band photometric redshifts from the following surveys: Visible and Infrared Survey Telescope for Astronomy Deep Extragalactic Observations and Canada-France-Hawaii Telescope Legacy Survey. The results indicate that the radio population experiences mild positive evolution out to z ~ 1.2 increasing their space density by a factor of ~3, consistent with results of several previous studies. Beyond z = 1.2, there is evidence of a slowing down of this evolution. Star-forming galaxies drive the more rapid evolution at low redshifts, z 1.2. The evolution is best fitted by pure luminosity evolution with star-forming galaxies evolving as (1 + z)2.47 ± 0.12 and AGN as (1 + z)1.18 ± 0.21M.Peer reviewe
Study of evaluation of groundwater in Gadilam basin using hydrogeochemical and isotope data
Gadilam river basin has gained its importance due to the presence of Neyveli Lignite open cast mines and other industrial complexes. It is also due to extensive depressurization of Cuddalore aquifer, and bore wells for New Veeranam Scheme are constructed downstream of the basin. Geochemical indicators of groundwater were used to identify the chemical processes that control hydrogeochemistry. Chemical parameters of groundwater such as pH, electrical conductivity, total dissolved solids, sodium (Na+), potassium (K+), calcium (Ca+), magnesium (Mg+), bicarbonate (HCO-3 ), sulfate (SO-4 ),phosphate (PO-4 ), and silica (H4SiO4) were determined. Interpretation of hydrogeochemical data suggests that leaching of ions followed by weathering and anthropogenic impact controls the chemistry of the groundwater. Isotopic study reveals that recharge from meteoric source in sedimentary terrain and rock-water interaction with significant evaporation prevails in hard rock region
Cross-site comparison of ribosomal depletion kits for Illumina RNAseq library construction
Background
Ribosomal RNA (rRNA) comprises at least 90% of total RNA extracted from mammalian tissue or cell line samples. Informative transcriptional profiling using massively parallel sequencing technologies requires either enrichment of mature poly-adenylated transcripts or targeted depletion of the rRNA fraction. The latter method is of particular interest because it is compatible with degraded samples such as those extracted from FFPE and also captures transcripts that are not poly-adenylated such as some non-coding RNAs. Here we provide a cross-site study that evaluates the performance of ribosomal RNA removal kits from Illumina, Takara/Clontech, Kapa Biosystems, Lexogen, New England Biolabs and Qiagen on intact and degraded RNA samples.
Results
We find that all of the kits are capable of performing significant ribosomal depletion, though there are differences in their ease of use. All kits were able to remove ribosomal RNA to below 20% with intact RNA and identify ~ 14,000 protein coding genes from the Universal Human Reference RNA sample at >1FPKM. Analysis of differentially detected genes between kits suggests that transcript length may be a key factor in library production efficiency.
Conclusions
These results provide a roadmap for labs on the strengths of each of these methods and how best to utilize them. Keywords: RNAseqr; RNA depletion; Illumina; NGS; ABRF; TranscriptomicsNational Cancer Institute (U.S.) (Grant P30-CA14051)National Institute of Environmental Health Sciences (Grant P30-ES002109
Star formation in high-redshift quasars: excess [O II] emission in the radio-loud population
We investigate the [O II] emission line properties of 18,508 quasars at z<1.6
drawn from the Sloan Digital Sky Survey (SDSS) quasar sample. The quasar sample
has been separated into 1,692 radio-loud and 16,816 radio-quiet quasars (RLQs
and RQQs hereafter) matched in both redshift and i'-band absolute magnitude.
We use the [O II]\lambda3726+3729 line as an indicator of star formation.
Based on these measurements we find evidence that star-formation activity is
higher in the RLQ population. The mean equivalent widths (EW) for [O II] are
EW([O II])_RL=7.80\pm0.30 \AA, and EW([O II])_RQ=4.77\pm0.06 \AA, for the RLQ
and RQQ samples respectively. The mean [O II] luminosities are \log[L([O
II])_RL/W]=34.31\pm0.01 and \log[L([O II])_RQ/W]=34.192\pm0.004 for the samples
of RLQs and RQQs respectively. Finally, to overcome possible biases in the EW
measurements due to the continuum emission below the [O II] line being
contaminated by young stars in the host galaxy, we use the ratio of the [O II]
luminosity to rest-frame i'-band luminosity, in this case, we find for the RLQs
\log[L([O II])_RL/L_opt]=-3.89\pm0.01 and \log[L([O
II])_RQ/L_opt]=-4.011\pm0.004 for RQQs. However the results depend upon the
optical luminosity of the quasar. RLQs and RQQs with the same high optical
luminosity \log(L_opt/W)>38.6, tend to have the same level of [O II] emission.
On the other hand, at lower optical luminosities \log(L_opt/W)<38.6, there is a
clear [O II] emission excess for the RLQs. As an additional check of our
results we use the [O III] emission line as a tracer of the bolometric
accretion luminosity, instead of the i'-band absolute magnitude, and we obtain
similar results.
Radio jets appear to be the main reason for the [O II] emission excess in the
case of RLQs. In contrast, we suggest AGN feedback ensures that the two
populations acquire the same [O II] emission at higher optical luminosities.Comment: 12 pages, 9 figures, accepted for publication in MNRA
Crop Updates 2006 - Katanning
This session covers sixteen papers from different authors
2006 SEASONAL OUTLOOK, David Stephens and Michael Meuleners, Department of Agriculture
Review of climate model summaries reported in the Department of Agriculture’s growing season outlooks, Meredith Fairbanks, Department of Agriculture
Farmers commodity outlook 2006, Thomas Schulz, Department of Agriculture
Why is salinity such a difficult problem for plant breeders? T J Flowers, TD Colmer, University of Western Australia
Matching nitrogen supply to wheat demand in 2005, Narelle Simpson, Ron McTaggart, Wal Anderson, Lionel Martin and Dave Allen, Department of Agriculture
Wheat varieties in 2006, Brenda Shackley, Department of Agriculture
Performance of dwarf potential milling oat varieties in Western Australian environments, Raj Malik and Kellie Winfield, Department of Agriculture
Field pea lessons for 2006, Rodger Beermir, Department of Agriculture
Better returns from Durum wheat, Shahahan Miyan, Department of Agriculture
Summer weeds can reduce grain yield and protein, Dr. Abul Hashem, Department of Agriculture, Dr Shahab Pathan, Department of Agriculture, Vikki Osten, Queensland Department of Primary Industries and Fisheries
Management of Summer Weeds, Alex Douglas, Department of Agriculture
Frost or Friction, Garren Knell, Steve Curtin, Wade Longmuir, Consult Ag Pty Ltd
PROFITING FROM MARGINAL LAND SEMINAR
Producing Bio-Diesel and rubber from marginal land?? Dr Henry Brockman, Department of Agriculture
SGSL Producer network – on ground implementation of saltbush based pastures, Justin Hardy, Arjen Ryder, John Paul Collins and Jessica Johns, Department of Agriculture
Enhancing the profitability of “Edenia” using saltbush and perenials, SGSL Producer case study, John Pepall, Jinka’s Hill LCDC
Investment in saltland pastures, Allan Herbert, Department of Agricultur
The effect of multiple internal representations on context rich instruction
This paper presents n-coding, a theoretical model of multiple internal mental
representations. The n-coding construct is developed from a review of cognitive
and imaging studies suggesting the independence of information processing along
different modalities: verbal, visual, kinesthetic, social, etc. A study testing
the effectiveness of the n-coding construct in an algebra-based mechanics
course is presented. Four sections differing in the level of n-coding
opportunities were compared. Besides a traditional instruction section used as
a control group, each of the remaining three treatment sections were given
context rich problems following the 'cooperative group problem solving'
approach which differed by the level of n-coding opportunities designed into
their laboratory environment. To measure the effectiveness of the construct,
problem solving skills were assessed as was conceptual learning using the Force
Concept Inventory. However, a number of new measures taking into account
students' confidence in concepts were developed to complete the picture of
student learning. Results suggest that using the developed n-coding construct
to design context rich environments can generate learning gains in problem
solving, conceptual knowledge and concept-confidence.Comment: Submitted to the American Journal of Physic
Universal WBC reduction
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75583/1/j.1537-2995.2000.40060751.x.pd
The Structural Complexity of the Human BORIS Gene in Gametogenesis and Cancer
BORIS/CTCFL is a paralogue of CTCF, the major epigenetic regulator of vertebrate genomes. BORIS is normally expressed only in germ cells but is aberrantly activated in numerous cancers. While recent studies demonstrated that BORIS is a transcriptional activator of testis-specific genes, little is generally known about its biological and molecular functions.Here we show that BORIS is expressed as 23 isoforms in germline and cancer cells. The isoforms are comprised of alternative N- and C-termini combined with varying numbers of zinc fingers (ZF) in the DNA binding domain. The patterns of BORIS isoform expression are distinct in germ and cancer cells. Isoform expression is activated by downregulation of CTCF, upregulated by reduction in CpG methylation caused by inactivation of DNMT1 or DNMT3b, and repressed by activation of p53. Studies of ectopically expressed isoforms showed that all are translated and localized to the nucleus. Using the testis-specific cerebroside sulfotransferase (CST) promoter and the IGF2/H19 imprinting control region (ICR), it was shown that binding of BORIS isoforms to DNA targets in vitro is methylation-sensitive and depends on the number and specific composition of ZF. The ability to bind target DNA and the presence of a specific long amino terminus (N258) in different isoforms are necessary and sufficient to activate CST transcription. Comparative sequence analyses revealed an evolutionary burst in mammals with strong conservation of BORIS isoproteins among primates.The extensive repertoire of spliced BORIS variants in humans that confer distinct DNA binding and transcriptional activation properties, and their differential patterns of expression among germ cells and neoplastic cells suggest that the gene is involved in a range of functionally important aspects of both normal gametogenesis and cancer development. In addition, a burst in isoform diversification may be evolutionarily tied to unique aspects of primate speciation
Herschel-ATLAS/GAMA: What determines the far-infrared properties of radio galaxies?
We perform a stacking analysis of Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) data in order to obtain isothermal dust temperatures and rest-frame luminosities at 250 μm (L_250), for a well-defined sample of 1599 radio sources over the H-ATLAS Phase 1/Galaxy and Mass Assembly (GAMA) area. The radio sample is generated using a combination of NRAO VLA Sky Survey data and K-band United Kingdom Infrared Telescope Deep Sky Survey–Large Area Survey data, over the redshift range 0.01 < z < 0.8. The far-infrared (FIR) properties of the sample are investigated as a function of 1.4-GHz luminosity, redshift, projected radio-source size and radio spectral index. In order to search for stellar-mass-dependent relations, we split the parent sample into those sources which are below and above 1.5 L∗_(K).
After correcting for stellar mass and redshift, we find no relation between the 250-μm luminosity and the 1.4-GHz radio luminosity of radio active galactic nuclei. This implies that a galaxy's nominal radio luminosity has little or no bearing on the star formation rate (SFR) and/or dust mass content of the host system, although this does not mean that other variables (e.g. radio source size) related to the jets do not have an effect. The L_250 of both the radio detected and non-radio-detected galaxies (defined as those sources not detected at 1.4 GHz but detected in the Sloan Digital Sky Survey with r′ 30 kpc) counterparts. The higher dust temperature suggests that this may be attributed to enhanced SFRs in compact radio galaxies, but whether this is directly or indirectly due to radio activity (e.g. jet-induced or merger-driven star formation) is as yet unknown.
For matched samples in L_K and g′–r′, sub-1.5 L∗_K and super-1.5 L∗_K radio-detected galaxies have 0.89±0.18 and 0.49±0.12 times the 250 μm luminosity of their non-radio-detected counterparts. Thus, while no difference in L_250 is observed in sub-1.5 L∗_K radio-detected galaxies, a strong deficit is observed in super-1.5 L∗_K radio-detected galaxies. We explain these results in terms of the hotter, denser and richer halo environments massive radio galaxies maintain and are embedded in. These environments are expected to quench the cold gas and dust supply needed for further star formation and therefore dust production. Our results indicate that all massive radio galaxies (>1.5 L∗_K) may have systematically lower FIR luminosities (∼25 per cent) than their colour-matched non-radio-detected counterparts. Finally, no relation between radio spectral index and L_250 is found for the subset of 1.4-GHz radio sources with detections at 330 MHz
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Microfoundations
This paper argues that the microfoundations programme can be understood as an implementation of an underlying methodological principle—methodological individualism—and that it therefore shares a fundamental ambiguity with that principle, viz, whether the macro must be derived from and therefore reducible to, or rather consistent with, micro-level behaviours. The pluralist conclusion of the paper is not that research guided by the principle of microfoundations is necessarily wrong, but that the exclusion of approaches not guided by that principle is indeed necessarily wrong. The argument is made via an examination of the advantages claimed for dynamic stochastic general equilibrium models, the relationship between parts and wholes in social science, and the concepts of reduction, substrate neutrality, the intentional stance, and hypostatisation
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