725 research outputs found
Effect of Winter Canola Cultivar on Seed Yield, Oil, and Protein Content
Canola (Brassica napus L.) is an oilseed crop that can produce healthy cooking oil and animal feed byproducts. Although it is a relatively new crop, approved for human consumption less than 40 yr ago, advances in breeding have allowed for its production as a winter crop in the southeastern United States. There is little published research, however, related to its performance and quality in this region. Therefore, a study was conducted during the 2014–2015 (Year 1) and 2015–2016 (Year 2) seasons in Tennessee. Twenty-three varieties were planted in a randomized complete block design with four replications across both years to determine seed yield, seed oil, and seed protein content. Differences in fertilizer application rates, planting, and harvest management and differences in weather conditions probably led to significant interactions between years. Cultivar yields ranged from 1269 to 2647 and 1494 to 4199 kg ha−1, seed oil content ranged from 44 to 48% and from 43 to 46%, and seed protein content ranged from 20 to 24% and from 19 to 23% for Years 1 and 2, respectively. In each year, open-pollinated cultivars had significantly lower yield and oil content but significantly greater protein content than hybrid cultivars. There was also a strong negative correlation between seed oil and seed protein and the linear models were significant (r = 0.88, p \u3c 0.0001 for Year 1; r = 0.85, p \u3c 0.0001 for Year 2). Recommended winter canola cultivars include Exp1302 and Hekip
Observation of the first gravitational microlensing event in a sparse stellar field : the Tago event
We report the observation of the first gravitational microlensing event in a
sparse stellar field, involving the brightest (V=11.4 mag) andclosest (~ 1 kpc)
source star to date. This event was discovered by an amateurastronomer, A.
Tago, on 2006 October 31 as a transient brightening, by ~4.5 mag during a ~15
day period, of a normal A-type star (GSC 3656-1328) in the Cassiopeia
constellation. Analysis of both spectroscopic observations and the light curve
indicates that this event was caused by gravitational microlensing rather than
an intrinsically variable star. Discovery of this single event over a 30 year
period is roughly consistent with the expected microlensing rate for the whole
sky down to V = 12 mag stars. However, the probability for finding events with
such a high magnification (~ 50) is much smaller, by a factor ~1/50, which
implies that the true event rate may be higher than expected. This discovery
indicates the potential of all sky variability surveys, employing frequent
sampling by telescopes with small apertures and wide fields of view, for
finding such rare transient events, and using the observations to explore
galactic disk structure and search for exo-planets.Comment: 13 pages, 2 tables, 3 figures, accepted by Ap
The inner kiloparsec of the jet in 3C264
We present new multi-frequency EVN, MERLIN and VLA observations of the radio
source 3C264, sensitive to linear scales ranging from the parsec to several
kiloparsecs. The observations confirm the existence of regions with different
properties in the first kiloparsec of the jet. The most remarkable feature is
the transition between a well collimated narrow jet at distances from the core
below 80 pc, to a conical-shaped wide jet, with an opening angle of 20 degrees.
Another change of properties, consisting of an apparent deflection of the jet
ridge line and a diminution of the surface brightness, occurs at a distance of
300 pc from the core, coincident with the radius of a ring observed at optical
wavelengths. Our observations add new pieces of information on the spectrum of
the radio-optical jet of 3C264, with results consistent with a synchrotron
emission mechanism and a spectrum break frequency in the infrared. Brightness
profiles taken perpendicularly to the jet of 3C264 are consistent with a spine
brightened jet at distances below 100 pc from the core, and an edge-brightened
jet beyond, which can be interpreted as evidence of a transverse jet velocity
structure. Our observations do not allow us to distinguish between the presence
of a face--on dust and gas disk at the center of the host galaxy of 3C264, or
rather an evacuated bubble. However, the properties of the jet structure, the
changes in the polarization angle, and the plausible jet orientation can be
naturally brought into agreement in the bubble scenario.Comment: 10 pages, 9 figures, accepted in A&
Design of Cationic Multi-Walled Carbon Nanotubes as Efficient siRNA Vectors for Lung Cancer Xenograft Eradication
Polo-Like Kinase (PLK1) has been identified as a potential target in cancer gene therapy via chemical or genetic inhibitory approaches. The biomedical applications of chemically functionalized carbon nanotubes (f-CNTs) in cancer therapy have been studied due to their ability to efficiently deliver siRNA intracellularly. In this study, we established the capacity of cationic MWNT-NH3+ to deliver the apoptotic siRNA against PLK1 (siPLK1) in Calu6 tumor xenografts by direct intratumoural injections. A direct comparison with cationic liposomes was made. This study validates the PLK1 gene as a potential target in cancer gene therapy including lung cancer, as demonstrated by the therapeutic efficacy of siPLK1:MWNT-NH3+ complexes and their ability to significantly improve animal survival. Biological analysis of the siPLK1:MWNT-NH3+ treated tumors by RT-PCR and Western blot, in addition to TUNEL staining confirmed the biological functionality of the siRNA intratumourally, suggesting that tumor eradication was due to PLK1 knockdown. Furthermore, by using a fluorescently labelled, non-coding siRNA sequence complexed with MWNT-NH3+, we established for the first time that the improved therapeutic efficacy observed in f-CNT-based siRNA delivery is directly proportional to the enhanced siRNA retention in the solid tumor and subsequent uptake by tumor cells after local administration in vivo
S021-06 OA. Potent and broad neutralizing antibodies from HIV-1 non-clade B infected donor reveal a new HIV-1 vaccine target
Large-scale gas disk around the radio galaxy Coma A
We present WSRT and VLA radio observations of the neutral hydrogen in the
radio galaxy Coma A. We detect extended HI absorption against both radio lobes
of Coma A, at distances of about 30 kpc from the centre. Coma A is the first
radio galaxy in which HI is seen in absorption at such large distances from the
nucleus. The match between the velocities of the neutral hydrogen and those of
the extended ionized gas suggests that they are part of the same disk-like
structure of at least 60 kpc in diameter. Most likely, this gas disk is partly
ionised by the bulk motion of the radio lobes expanding into it. The gas mass
of this disk is at least 10^9 Msun. The relatively regular structure of the gas
disk suggests that a merger occurred involving at least one large gas-rich
galaxy, at least a few times 10^8 yr ago.Comment: Accepted for publication in A&A, 8 pages, 8 figure
3C459: A highly asymmetric radio galaxy with a starburst
Multifrequency radio observations of the radio galaxy 3C459 using MERLIN, VLA
and the EVN, and an optical HST image using the F702W filter are presented. The
galaxy has a very asymmetric radio structure, a high infrared luminosity and a
young stellar population. The eastern component of the double-lobed structure
is brighter, much closer to the nucleus and is significantly less polarized
than the western one. This is consistent with the jet on the eastern side
interacting with dense gas, which could be due to a merged companion or dense
cloud of gas. The HST image of the galaxy presented here exhibits filamentary
structures, and is compared with the MERLIN 5-GHz radio map. EVN observations
of the prominent central component, which has a steep radio spectrum, show a
strongly curved structure suggesing a bent or helical radio jet. The radio
structure of 3C459 is compared with other highly asymmetric, Fanaroff-Riley II
radio sources, which are also good candidates for studying jet-cloud
interactions. Such sources are usually of small linear size and it is possible
that the jets are interacting with clouds of infalling gas that fuel the radio
source.Comment: 10 pages, 6 figures, 2 table
The helium-rich cataclysmic variable SBSS 1108+574
We present time-resolved spectroscopy and photometry of the dwarf nova SBSS 1108+574, obtained during the 2012 outburst. Its quiescent spectrum is unusually rich in helium, showing broad, double-peaked emission lines from the accretion disc. We measure a line flux ratio He I 5875/Hα = 0.81 ± 0.04, a much higher ratio than typically observed in cataclysmic variable stars (CVs). The outburst spectrum shows hydrogen and helium in absorption, with weak emission of Hα and He I 6678, as well as strong He II emission.
From our photometry, we find the superhump period to be 56.34 ± 0.18 min, in agreement with the previously published result. The spectroscopic period, derived from the radial velocities of the emission lines, is found to be 55.3 ± 0.8 min, consistent with a previously identified photometric orbital period, and significantly below the normal CV period minimum. This indicates that the donor in SBSS 1108+574 is highly evolved. The superhump excess derived from our photometry implies a mass ratio of q = 0.086 ± 0.014. Our spectroscopy reveals a grazing eclipse of the large outbursting disc. As the disc is significantly larger during outburst, it is unlikely that an eclipse will be detectable in quiescence. The relatively high accretion rate implied by the detection of outbursts, together with the large mass ratio, suggests that SBSS 1108+574 is still evolving towards its period minimum
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