Influence of balanced application of N, P and S fertilizers on forage yield and quality of timothy in northeastern Saskatchewan

Non-Peer Reviewe

Tumbleweeds and airborne gravitational noise sources for LIGO

Gravitational-wave detectors are sensitive not only to astrophysical gravitational waves, but also to the fluctuating Newtonian gravitational forces of moving masses in the ground and air around the detector. This paper studies the gravitational effects of density perturbations in the atmosphere, and from massive airborne objects near the detector. These effects were previously considered by Saulson; in this paper I revisit these phenomena, considering transient atmospheric shocks, and the effects of sound waves or objects colliding with the ground or buildings around the test masses. I also consider temperature perturbations advected past the detector as a source of gravitational noise. I find that the gravitational noise background is below the expected noise floor even of advanced interferometric detectors, although only by an order of magnitude for temperature perturbations carried along turbulent streamlines. I also find that transient shockwaves in the atmosphere could potentially produce large spurious signals, with signal-to-noise ratios in the hundreds in an advanced interferometric detector. These signals could be vetoed by means of acoustic sensors outside of the buildings. Massive wind-borne objects such as tumbleweeds could also produce gravitational signals with signal-to-noise ratios in the hundreds if they collide with the interferometer buildings, so it may be necessary to build fences preventing such objects from approaching within about 30m of the test masses.Comment: 15 pages, 10 PostScript figures, uses REVTeX4.cls and epsfig.st

Arthropods, Silvertop, and Grass Seed Yields

High numbers of various arthropods early in the season, especially thrips, mites, and grass plant bugs, were associated with silvertop injury in six grass seed fields in Saskatchewan in 995. Insect numbers in sweep samples were frequently suppressed for one or two weeks in plots sprayed with an insecticide. Four fields had low levels of arthropods early in the season andoelow incidence of silvertop later on. In a field of Russian wildrye grass with high arthropod populations, seed yield was highest in plots that had been sprayed with insecticide prior to the boot stage of grass growth. In one field of Kentucky bluegrass with moderate silvertop levels, plots that had been burned the previous autumn had higher yields than those that had been scalped (closely mowed) and the residue removed, or that had been mowed and the residue left on the plots

A New Strategy for Deep Wide-Field High Resolution Optical Imaging

We propose a new strategy for obtaining enhanced resolution (FWHM = 0.12 arcsec) deep optical images over a wide field of view. As is well known, this type of image quality can be obtained in principle simply by fast guiding on a small (D = 1.5m) telescope at a good site, but only for target objects which lie within a limited angular distance of a suitably bright guide star. For high altitude turbulence this 'isokinetic angle' is approximately 1 arcminute. With a 1 degree field say one would need to track and correct the motions of thousands of isokinetic patches, yet there are typically too few sufficiently bright guide stars to provide the necessary guiding information. Our proposed solution to these problems has two novel features. The first is to use orthogonal transfer charge-coupled device (OTCCD) technology to effectively implement a wide field 'rubber focal plane' detector composed of an array of cells which can be guided independently. The second is to combine measured motions of a set of guide stars made with an array of telescopes to provide the extra information needed to fully determine the deflection field. We discuss the performance, feasibility and design constraints on a system which would provide the collecting area equivalent to a single 9m telescope, a 1 degree square field and 0.12 arcsec FWHM image quality.Comment: 46 pages, 22 figures, submitted to PASP, a version with higher resolution images and other supplementary material can be found at http://www.ifa.hawaii.edu/~kaiser/wfhr

Patients’ experiences of life after bariatric surgery and follow-up care:A qualitative study

ObjectivesBariatric surgery is the most clinically effective treatment for people with severe and complex obesity, however, the psychosocial outcomes are less clear. Follow-up care after bariatric surgery is known to be important, but limited guidance exists on what this should entail, particularly related to psychological and social well-being. Patients’ perspectives are valuable to inform the design of follow-up care. This study investigated patients’ experiences of life after bariatric surgery including important aspects of follow-up care, in the long term.DesignA qualitative study using semistructured individual interviews. A constant comparative approach was used to code data and identify themes and overarching concepts.SettingBariatric surgery units of two publicly funded hospitals in the South of England.ParticipantsSeventeen adults (10 women) who underwent a primary operation for obesity (mean time since surgery 3.11 years, range 4 months to 9 years), including Roux-en-Y gastric bypass, adjustable gastric band and sleeve gastrectomy, agreed to participate in the interviews.ResultsExperiences of adapting to life following surgery were characterised by the concepts of ‘normality’ and ‘ambivalence’, while experiences of ‘abandonment’ and ‘isolation’ dominated participants’ experiences of follow-up care. Patients highlighted the need for more flexible, longer-term follow-up care that addresses social and psychological difficulties postsurgery and integrates peer support.ConclusionsThis research highlights unmet patient need for more accessible and holistic follow-up care that addresses the long-term multidimensional impact of bariatric surgery. Future research should investigate effective and acceptable follow-up care packages for patients undergoing bariatric surgery

The Impact of Atmospheric Fluctuations on Degree-scale Imaging of the Cosmic Microwave Background

Fluctuations in the brightness of the Earth's atmosphere originating from water vapor are an important source of noise for ground-based instruments attempting to measure anisotropy in the Cosmic Microwave Background. This paper presents a model for the atmospheric fluctuations and derives simple expressions to predict the contribution of the atmosphere to experimental measurements. Data from the South Pole and from the Atacama Desert in Chile, two of the driest places on Earth, are used to assess the level of fluctuations at each site.Comment: 29 pages, 7 figures, 1 table, appears in The Astrophysical Journa

Adsorption induced reconstruction of the Cu(110) surface

The formation of the O/Cu(110)-(2 × 1) and H/Cu(110)-(1 × 2) superstructures has been investigated by a LEED beam profile analysis. The oxygen induced reconstruction proceeds at later stages by creation of holes on flat terraces. This could not be observed at the hydrogen induced missing row reconstruction. The formation of the missing row structure proceeds most probably via nucleation at steps and subsequent growth of (1 × 2) islands. The influence of different distributions of steps and islands on beam profiles is discussed

Induction of Mutants with Ectopic Expression of Condensed Tannins

Leaves of 47,000 Lotus japonicus plants were screened using a butanol:HCl histochemical test to select “gain of function” mutants. These plants were progeny from L. japonicus lines which were transformed with T-DNA constructs containing either the maize Ds or Ac transposon (Thykjaer et al., 1995). Among 21 putative leaf tannin mutants, five (tan1-5) were characterized for synthesis of condensed tannins, leucocyanidin reductase activity and the presence of Ac and the selectable marker gene, nptII . A range of leaf tannin content among other Lotus species was also characterized