1,734 research outputs found
Seed phosphorus in wheat and lupins
Trial 90NO119
Seed P in wheat.
Location: Greenhills.
Design: 2 applied P x 3 seed P x 4 replicates, sowing wheat (cv. Aroona) seed from 89N33 at 70 kg/ha on May 15, 1990.
Trial 90NO120
Seed P in wheat.
Location: York
Design: 2 applied from P x 3 seed P x 4 replicates, 89N33 at 70 kg/ha on May 25, 1990.
Trial 90NO117
Seed P in lupins
Location: Greenhills.
Design: 2 applied P x 3 seed P x 4 replicates, sowing lupins (cv. Gungurru) from 85BA35 at 100 kg/ha on May 15, 1990.
Trial 90NO118
Seed P in lupins.
Location: York
Design: 3 applied P x 3 seed P x 4 replicates, sowing lupins (cv. Gungurru) from 85BA35 at 100 kg/ha on May 25, 1990.
Trial 90MD9
Phosphorus placement and seed P.
Aim: To measure the effects of phosphate fertilizer placement on the response of lupins to varying seed P levels
A new population of recently quenched elliptical galaxies in the SDSS
We use the Sloan Digital Sky Survey to investigate the properties of massive
elliptical galaxies in the local Universe (z\leq0.08) that have unusually blue
optical colors. Through careful inspection, we distinguish elliptical from
non-elliptical morphologies among a large sample of similarly blue galaxies
with high central light concentrations (c_r\geq2.6). These blue ellipticals
comprise 3.7 per cent of all c_r\geq2.6 galaxies with stellar masses between
10^10 and 10^11 h^{-2} {\rm M}_{\sun}. Using published fiber spectra
diagnostics, we identify a unique subset of 172 non-star-forming ellipticals
with distinctly blue urz colors and young (< 3 Gyr) light-weighted stellar
ages. These recently quenched ellipticals (RQEs) have a number density of
2.7-4.7\times 10^{-5}\,h^3\,{\rm Mpc}^{-3} and sufficient numbers above
2.5\times10^{10} h^{-2} {\rm M}_{\sun} to account for more than half of the
expected quiescent growth at late cosmic time assuming this phase lasts 0.5
Gyr. RQEs have properties that are consistent with a recent merger origin
(i.e., they are strong `first-generation' elliptical candidates), yet few
involved a starburst strong enough to produce an E+A signature. The preferred
environment of RQEs (90 per cent reside at the centers of < 3\times
10^{12}\,h^{-1}{\rm M}_{\sun} groups) agrees well with the `small group scale'
predicted for maximally efficient spiral merging onto their halo center and
rules out satellite-specific quenching processes. The high incidence of Seyfert
and LINER activity in RQEs and their plausible descendents may heat the
atmospheres of small host halos sufficiently to maintain quenching.Comment: 26 pages, 9 figures. Revised version; accepted for publication in
MNRA
Crystallographic and magnetic identification of secondary phase in orientated Bi5Fe0.5Co0.5Ti3O15 ceramics
Oxide materials which exhibit both ferroelectricity
and ferromagnetism are of great interest for sensors and memory
applications. Layered bismuth titanates with an Aurivillius
structure, (BiFeO3)nBi4Ti3O12, can possess ferroelectric and
ferromagnetic order parameters simultaneously. It has recently
been demonstrated that one such example,
Bi5Fe0.5Co0.5Ti3O15,where n = 1 with half the Fe3+ sites substituted
by Co3+ ions, exhibits both ferroelectric and ferromagnetic
properties at room temperature. Here we report the fabrication
of highly-oriented polycrystalline ceramics of this material,
prepared via molten salt synthesis and uniaxial pressing of high
aspect ratio platelets. Electron backscatter images showed that
there is a secondary phase within the ceramic matrix which is
rich in cobalt and iron, hence this secondary phase could
contribute in the main phase ferromagnetic property. The
concentration of the secondary phase obtained from secondary
electron microscopy is estimated at less than 2.5 %, below the
detection limit of XRD. TEM was used to identify the
crystallographic structure of the secondary phase, which was
shown to be cobalt ferrite, CoFe2O4. It is inferred from the data
that the resultant ferromagnetic response identified using VSM
measurements was due to the presence of the minor secondary
phase. The Remanent magnetization at room temperature was
Mr â 76 memu/g which dropped down to almost zero (Mr â 0.8
memu/g) at 460 oC, far lower than the anticipated for CoFe2O4
New discoveries at Woolsey Mound, MC118, northern Gulf of Mexico
Woolsey Mound, a 1km-diameter carbonate-gas hydrate complex in the northern Gulf of Mexico, is the site of the Gulfâs only seafloor monitoring station-observatory in its only research reserve, Mississippi Canyon 118. Active venting, outcropping hydrate, and a thriving chemosynthetic community recommend the site for study. Since 2005, the Gulf of Mexico Hydrates Research Consortium has been conducting multidisciplinary studies to 1. Characterize the site, 2. Establish a facility for real-time monitoring-observing of gas hydrates in a natural setting, 3. Study the effects of gas hydrates on seafloor stability, 4. Establish fluid migration routes and estimates of fluid-flux at the site, 5. Establish the interrelationships between the
organisms at the vent site and the association-dissociation of hydrates. A variety of novel geological, geophysical, geochemical and biological studies has been designed and
conducted, some in survey mode, others in monitoring mode. Geophysical studies involving merging multiple seismic data acquisition systems accompanied by the application of custom processing techniques verify communication of surface features with deep structures. Supporting geological data derive from innovative recovery techniques. Geochemical sensors, used experimentally in survey mode, including aboard an AUV, double as monitoring devices. A suite of pore-fluid sampling devices has returned data that capture change at the site in daily increments; using only noise as an energy source, hydrophones have
returned daily fluctuations in physical properties. Ever-expanding capabilities of a custom-ROV have been determined by research needs. Processing of new as well as conventional data via unconventional means
has resulted in the discovery of new featuresâŠ..vents, faults, benthic faunaâŠ..and modification of others including pockmarks, hydrate outcrops, vent activity, and water-column chemical plumes.
Though real-time monitoring awaits communications and power link to land, periodic data-collection reveals a carbonate-hydrate mound, part of an immensely complex hydrocarbon system
Rest-Frame Near-Infrared Radial Light Profiles up to z=3 from JWST/NIRCam: Wavelength Dependence of the S\'ersic Index
We examine the wavelength dependence of radial light profiles based on
S\'ersic index measurements of 1067 galaxies with M
10M and in the redshift range . The sample and
rest-frame optical light profiles are drawn from CANDELS3D-HST; rest-frame
near-infrared light profiles are inferred from CEERS JWST/NIRCam imaging.
shows only weak dependence on wavelength, regardless of redshift, galaxy mass
and type: on average, star-forming galaxies have and quiescent
galaxies have in the rest-frame optical and near-infrared. The strong
correlation at all wavelengths between and star-formation activity implies
a physical connection between the radial stellar mass profile and
star-formation activity. The main caveat is that the current sample is too
small to discern trends for the most massive galaxies (M).Comment: 15 pages, 7 figures, Submitted to ApJ. Comments welcom
The uptake of soluble and nanoparticulate imaging isotope in model liver tumours after intra-venous and intra-arterial administration
Delivery of chemotherapeutic drugs to tumours by reformulation as nanoparticles has often been proposed as a means of facilitating increased selective uptake, exploiting the increased permeability of the tumour vasculature. However realisation of this improvement in drug delivery in cancer patients has met with limited success. We have compared tumour uptake of soluble Tc99m-pertechnetate and a colloid of nanoparticles with a Tc99m core, using both intra-venous and intra-arterial routes of administration in a rabbit liver VX2 tumour model. The radiolabelled nanoparticles were tested both in untreated and cationised form. The results from this tumour model in an internal organ show a marked advantage in intra-arterial administration over the intra-venous route, even for the soluble isotope. Tumour accumulation of nanoparticles from arterial administration was augmented by cationisation of the nanoparticle surface with histone proteins, which consistently facilitated selective accumulation within microvessels at the periphery of tumours.Sources of support for this research: Sirtex Medical Ltd, Sydney
Australia
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Evaluation of an emergency department lean process improvement program to reduce length of stay
Study objective
In recent years, lean principles have been applied to improve wait times in the emergency department (ED). In 2009, an ED process improvement program based on lean methods was introduced in Ontario as part of a broad strategy to reduce ED length of stay and improve patient flow. This study seeks to determine the effect of this program on ED wait times and quality of care.
Methods
We conducted a retrospective cohort study of all ED visits at program and control sites during 3 program waves from April 1, 2007, to June 30, 2011, in Ontario, Canada. Time series analyses of outcomes before and after the program and difference-in-differences analyses comparing changes in program sites with control sites were conducted.
Results
In before-after models among program sites alone, 90th percentile ED length of stay did not change in wave 1 (â14 minutes [95% confidence interval {CI} â47 to 20]) but decreased after wave 2 (â87 [95% CI â108 to â66]) and wave 3 (â33 [95% CI â50 to â17]); median ED length of stay decreased after wave 1 (â18 [95% CI â24 to â12]), wave 2 (â23 [95% CI â27 to â19]), and wave 3 (â15 [95% CI â18 to â12]). In all waves, decreases were observed in time to physician assessment, left-without-being-seen rates, and 72-hour ED revisit rates. In the difference-in-difference models, in which changes in program sites were compared with controls, the program was associated with no change in 90th percentile ED length of stay in wave 2 (17 [95% CI â0.2 to 33]) and increases in wave 1 (23 [95% CI 0.9 to 45]) and wave 3 (31 [95% CI 10 to 51]), modest reductions in median ED length of stay in waves 2 and 3 alone, and a decrease in time to physician assessment in wave 3 alone.
Conclusion
Although the program reduced ED waiting times, it appeared that its benefits were diminished or disappeared when compared with that of control sites, which were exposed to system-wide initiatives such as public reporting and pay for performance. This study suggests that further evaluation of the effectiveness of lean methods in the ED is warranted before widespread implementation
Gene expression in American lobster (Homarus americanus) with epizootic shell disease
Author Posting. © National Shellfisheries Association, 2012. This article is posted here by permission of National Shellfisheries Association for personal use, not for redistribution. The definitive version was published in Journal of Shellfish Research 31 (2012): 505-513, doi:10.2983/035.031.0210.Epizootic shell disease (ESD) has been reported widely in American lobster (Homarus americanus, Milne Edwards) in southern New England. The appearance of irregular, deep lesionsâcharacteristic of ESDâhas been associated previously with elevated levels of ecdysteroids and premature molting, but the underlying molecular and physiological changes associated with ESD remain poorly understood. Previously, we identified several genes, including arginine kinase and hemocyanin, that were expressed differentially in lobsters exhibiting signs of ESD (diseased) versus those lobsters exhibiting no signs of ESD (assumed healthy), and quantified their expression. In this study, we extend these findings and measure expression of a suite of 12 genes in tissues from 36 female lobsters of varying disease condition. In addition, molt stage is evaluated as a possible confounding factor in the expression of the selected genes. The expression of several genes changed significantly with disease stage. Arginine kinase expression decreased significantly in thoracic muscle of lobsters with signs of ESD. Ecdysteroid receptor expression was elevated significantly in both muscle and hepatopancreas of lobsters with signs of ESD. CYP45, a cytochrome P450 form that was shown previously to covary with ecdysteroid levels and to be inducible by some xenobiotics, showed significantly increased expression in hepatopancreas of lobsters with signs of ESD. Together, these results demonstrate that the expression of several genes is altered in lobsters showing signs of ESD, even when accounting for variation in molt stage. Given the observed changes in ecdysteroid receptor, arginine kinase, and CYP45 expression, further investigations of the association, if any, between molting, muscular function and xenobiotic metabolism and ESD are warranted.This work was supported by the National Marine
Fisheries Service as the New England Lobster Research
Initiative: Lobster Shell Disease under NOAA grant
NA06NMF4720100 to the University of Rhode Island Fisheries
Center
Improving the representativeness of UKâs national COVID-19 Infection Survey through spatio-temporal regression and post-stratification
Population-representative estimates of SARS-CoV-2 infection prevalence and antibody levels in specific geographic areas at different time points are needed to optimise policy responses. However, even population-wide surveys are potentially impacted by biases arising from differences in participation rates across key groups. Here, we used spatio-temporal regression and post-stratification models to UKâs national COVID-19 Infection Survey (CIS) to obtain representative estimates of PCR positivity (6,496,052 tests) and antibody prevalence (1,941,333 tests) for different regions, ages and ethnicities (7-December-2020 to 4-May-2022). Not accounting for vaccination status through post-stratification led to small underestimation of PCR positivity, but more substantial overestimations of antibody levels in the population (up to 21 percentage points), particularly in groups with low vaccine uptake in the general population. There was marked variation in the relative contribution of different areas and age-groups to each wave. Future analyses of infectious disease surveys should take into account major drivers of outcomes of interest that may also influence participation, with vaccination being an important factor to consider
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