836 research outputs found
Economic aspects of the production and marketing of hardy nursery stock
End of Project ReportA census of the Nursery Stock industry, carried out in autumn 1997, valued the sales of plants
produced by the industry in 1996 at £18.8m. In the period since a previous census in 1994
field production of nursery stock expanded by 17% while the production of container plants
shifted towards the greater use of protected cultivation. Employment in the industry rose by
28% to 912 full time equivalent jobs.
Kildare was predominant in the production of containerised plants while Tipperary was the
most important county for field production. Together, these two counties produced nearly half
the value of the industry. Together with Cork, Dublin, Kilkenny and Wicklow they accounted
for three quarters of the value of the industry.
The industry was concentrated in that the largest 10% of the nurseries produced 59% of the
value of the industry. As nursery size increased, the value of sales output per person rose
sharply. Larger nurseries were also more productive per unit area.
Exports were valued at £3.45m and imports at £2.22m. The main lines exported were
ornamental shrubs followed by liners and deciduous trees. Two thirds of the exports were
destined for Great Britain with the remainder going to Northern Ireland. Exporting was even
more concentrated than production with the largest 10% of the nurseries providing 83% of the
exports. The main imports were deciduous trees and liners. Two thirds of the imports
originated from the continent and the remainder were from Great Britain.
Small nurseries reported that capital and profitability were the principal factors limiting
expansion of their nurseries. Larger nurseries however placed the availability of suitable staff
as the main limiting factor. The most common difficulty reported by exporters was the cost of
transport and a number of problems relating to the difficulties that individual nurseries or
small groups have in supplying a large, discerning and relatively distant market. This
underlined the need for increased co-ordination and co-operation in the future
X-ray photoelectron spectroscopy study of the passive films formed on thermally sprayed and wrought Inconel 625
There is a well known performance gap in corrosion resistance between thermally sprayed corrosion resistant coatings and the equivalent bulk materials. Interconnected porosity has an important and well known effect, however there are additional relevant microstructural effects. Previous work has shown that a compositional difference exists between the regions of resolidified and non-melted material that exist in the as-sprayed coatings. The resolidified regions are depleted in oxide forming elements due to formation of oxides during coating deposition. Formation of galvanic cells between these different regions is believed to decrease the corrosion resistance of the coating. In order to increase understanding of the details of this effect, this work uses X-ray photoelectron spectroscopy (XPS) to study the passive films formed on thermally sprayed coatings (HVOF) and bulk Inconel 625, a commercially available corrosion resistant Ni-Cr-Mo-Nb alloy. Passive films produced by potentiodynamic scanning to 400mV in 0.5M sulphuric acid were compared with air formed films. The poorer corrosion performance of the thermally sprayed coatings was attributed to Ni(OH)2, which forms a loose, non-adherent and therefore non-protective film. The good corrosion resistance of wrought Inconel 625 is due to formation of Cr, Mo and Nb oxides.
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Six-year body composition change in male elite senior rugby league players
This study investigated the change in body composition and bone mineral content (BMC) of senior rugby league (RL) players between 2008 and 2014. Twelve male professional RL players (age, 24.6 ± 4.0 years; stature, 183.4 ± 8.4 cm) received a dual-energy X-ray absorptiometry scan during preseason in 2008 and 2014. Between 2008 and 2014, very likely increases in leg lean mass (LM), total trunk and leg BMC, and a likely increase in arm BMC and possible increases in body mass (BM), total and trunk fat mass (FM), and total, trunk and arm LM were observed. Unlikely decreases and unclear changes in leg and arm FM were also found. Large negative correlations were observed between age and BM (r = −0.72), LM (r = −0.70), FM (r = −0.61) and BMC (r = −0.84) change. Three participants (19.1 ± 1.6 years) increased LM by 7.0–9.3 kg. Younger players had the largest increases in LM during this period, although an older player (30-year old) still increased LM. Differences in body composition change were also observed for participants of the same age, thus contextual factors should be considered. This study demonstrates the individuality of body composition changes in senior professional rugby players, while considering the potential change in young athletes
The Question of Questions: What is a Gene? Comments on Rolston and Griffths & Stotz
If the question “What is a gene?” proves to be worth asking it must be able to elicit an answer which both recognizes and address the reasons why the concept of the gene ever seemed to be something worth getting excited about in the first place as well analyzing and evaluating the latest develops in the molecular biology of DNA. Each of the preceding papers fails to do one of these and sufferrs the consequences. Where Rolston responds to the apparent failure of molecular biology to make good on the desideratum of the classical gene by veering off into fanciful talk about “cybernetic genes,” Griffiths and Stotz lose themselves in the molecular fine print and forget to ask themselves why “genes” should be of any special interst anyway
Spinodal Decomposition in a Binary Polymer Mixture: Dynamic Self Consistent Field Theory and Monte Carlo Simulations
We investigate how the dynamics of a single chain influences the kinetics of
early stage phase separation in a symmetric binary polymer mixture. We consider
quenches from the disordered phase into the region of spinodal instability. On
a mean field level we approach this problem with two methods: a dynamical
extension of the self consistent field theory for Gaussian chains, with the
density variables evolving in time, and the method of the external potential
dynamics where the effective external fields are propagated in time. Different
wave vector dependencies of the kinetic coefficient are taken into account.
These early stages of spinodal decomposition are also studied through Monte
Carlo simulations employing the bond fluctuation model that maps the chains --
in our case with 64 effective segments -- on a coarse grained lattice. The
results obtained through self consistent field calculations and Monte Carlo
simulations can be compared because the time, length, and temperature scales
are mapped onto each other through the diffusion constant, the chain extension,
and the energy of mixing. The quantitative comparison of the relaxation rate of
the global structure factor shows that a kinetic coefficient according to the
Rouse model gives a much better agreement than a local, i.e. wave vector
independent, kinetic factor. Including fluctuations in the self consistent
field calculations leads to a shorter time span of spinodal behaviour and a
reduction of the relaxation rate for smaller wave vectors and prevents the
relaxation rate from becoming negative for larger values of the wave vector.
This is also in agreement with the simulation results.Comment: Phys.Rev.E in prin
the WAF method for non-homogeneous SWE with pollutant
This paper deals with the extension of the WAF method to discretize Shallow Water Equations with pollutants. We consider two different versions of the WAF method, by approximating the intermediate waves using the flux of HLL or the direct approach of HLLC solver. It is seen that both versions can be written under the same form with different definitions for the approximation of the velocity waves. We also propose an extension of the method to non-homogeneous systems. In the case of homogeneous systems it is seen that we can rewrite the third component of the numerical flux in terms of an intermediate wave speed approximation. We conclude that – in order to have the same relation for non-homogeneous systems – the approximation of the intermediate wave speed must be modified. The proposed extension of the WAF method preserves all stationary solutions, up to second order accuracy, and water at rest in an exact way, even with arbitrary pollutant concentration. Finally, we perform several numerical tests, by comparing it with HLLC solver, reference solutions and analytical solutions
First Observation of Coherent Production in Neutrino Nucleus Interactions with 2 GeV
The MiniBooNE experiment at Fermilab has amassed the largest sample to date
of s produced in neutral current (NC) neutrino-nucleus interactions at
low energy. This paper reports a measurement of the momentum distribution of
s produced in mineral oil (CH) and the first observation of coherent
production below 2 GeV. In the forward direction, the yield of events
observed above the expectation for resonant production is attributed primarily
to coherent production off carbon, but may also include a small contribution
from diffractive production on hydrogen. Integrated over the MiniBooNE neutrino
flux, the sum of the NC coherent and diffractive modes is found to be (19.5
1.1 (stat) 2.5 (sys))% of all exclusive NC production at
MiniBooNE. These measurements are of immediate utility because they quantify an
important background to MiniBooNE's search for
oscillations.Comment: Submitted to Phys. Lett.
Risk Categorization Using New American College of Cardiology/American Heart Association Guidelines for Cholesterol Management and Its Relation to Alirocumab Treatment Following Acute Coronary Syndromes
BACKGROUND: The 2018 US cholesterol management guidelines recommend
additional lipid-lowering therapies for secondary prevention in patients with lowdensity lipoprotein cholesterol ≥70 mg/dL or non−high-density lipoprotein cholesterol
≥100 mg/dL despite maximum tolerated statin therapy. Such patients are considered
at very high risk (VHR) based on a history of >1 major atherosclerotic cardiovascular
disease (ASCVD) event or a single ASCVD event and multiple high-risk conditions.
We investigated the association of US guideline-defined risk categories with the
occurrence of ischemic events after acute coronary syndrome and reduction of
those events by alirocumab, a PCSK9 (proprotein convertase subtilisin/kexin type 9)
inhibitor.
METHODS: In the ODYSSEY OUTCOMES trial (Evaluation of Cardiovascular
Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab),
patients with recent acute coronary syndrome and residual dyslipidemia despite
optimal statin therapy were randomly assigned to alirocumab or placebo. The primary
trial outcome (major adverse cardiovascular events, ie, coronary heart disease death,
nonfatal myocardial infarction, is
What killed Frame Lake? A precautionary tale for urban planners
Frame Lake, located within the city of Yellowknife, Northwest Territories, Canada, has been identified as requiring significant remediation due to its steadily declining water quality and inability to support fish by the 1970s. Former gold mining operations and urbanization around the lake have been suspected as probable causes for the decline in water quality. While these land-use activities are well documented, li
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