400 research outputs found

    A note on the effect of the composition of barley produced at different locations on performance of growing pigs.

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    peer-reviewedLocation of production has been shown to affect the nutritive value of barley for growing pigs, but there is a lack of information regarding the effect of this factor on pig performance. The barley variety “Riviera” was produced at nine different locations in Northern Ireland and formulated into diets (barley, soyabean meal and tallow at 650, 283 and 30 g/kg, respectively) for growing pigs. Diets were offered ad libitum to a total of 72 individually housed pigs from 8 to 11 weeks of age. Average start and end weights were 19 and 34 kg, respectively. Location of production had no significant effect on animal performance although a wide range was observed, which may be important under commercial conditions. Barley specific weight was not strongly correlated (r2 < 0.10) with any performance trait indicating that an alternative means of predicting the nutritive value of barely for pigs is required. A significant positive relationship was observed between barley β-glucan concentration and feed conversion ratio (r2 = 0.65).The authors acknowledge the Trustees of the Thomas Henry Scholarship, The Queen’s University of Belfast (QUB) and the Department of Agriculture and Rural Development for Northern Ireland (DARD), for the financial support which enabled this research to be undertaken

    Potential impact of group 2 (ALS inhibitor) herbicide residue on winter wheat survival – early reconnaissance

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    Non-Peer ReviewedNext to the coinciding harvest of spring crops, the biggest challenge winter wheat seeding faces is finding early matured and harvested crop land for seeding at the optimum window from late August to early September. Pulse stubble provides an opportunity to get winter wheat seeded in a timely basis. Growing winter wheat on pulse stubble is commonly discouraged due to the very limited residue and potential for snow trap. As overwinter success is connected to snow cover and subsequent insulation against cold temperatures. We propose another challenge that may be limiting success on pulse stubble. The repeated use ALS inhibiting (Group 2) herbicides and soil residual that can inhibit root growth, nutrient uptake and subsequent fall seedling establishment. A reconnaissance study was conducted on two locations, each with pulse stubble but with differing Group 2 herbicide residue. Soil temperature monitoring showed that of the three winter wheat cultivars examined, all should have easily survived the winter of 2010-11. Significant impact on stand survival and yield was observed on the soil having Group 2 residues. A cultivar interaction was also noted. Further investigation would facilitate identifying potential crop nutrition management techniques to overcome agronomic challenges of successfully growing winter wheat on pulse stubble. Investigation of winter wheat cultivar tolerance to ALS inhibiting herbicide residues would also be of value

    Applications of Hilbert Module Approach to Multivariable Operator Theory

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    A commuting nn-tuple (T1,,Tn)(T_1, \ldots, T_n) of bounded linear operators on a Hilbert space \clh associate a Hilbert module H\mathcal{H} over C[z1,,zn]\mathbb{C}[z_1, \ldots, z_n] in the following sense: C[z1,,zn]×HH,(p,h)p(T1,,Tn)h,\mathbb{C}[z_1, \ldots, z_n] \times \mathcal{H} \rightarrow \mathcal{H}, \quad \quad (p, h) \mapsto p(T_1, \ldots, T_n)h,where pC[z1,,zn]p \in \mathbb{C}[z_1, \ldots, z_n] and hHh \in \mathcal{H}. A companion survey provides an introduction to the theory of Hilbert modules and some (Hilbert) module point of view to multivariable operator theory. The purpose of this survey is to emphasize algebraic and geometric aspects of Hilbert module approach to operator theory and to survey several applications of the theory of Hilbert modules in multivariable operator theory. The topics which are studied include: generalized canonical models and Cowen-Douglas class, dilations and factorization of reproducing kernel Hilbert spaces, a class of simple submodules and quotient modules of the Hardy modules over polydisc, commutant lifting theorem, similarity and free Hilbert modules, left invertible multipliers, inner resolutions, essentially normal Hilbert modules, localizations of free resolutions and rigidity phenomenon. This article is a companion paper to "An Introduction to Hilbert Module Approach to Multivariable Operator Theory".Comment: 46 pages. This is a companion paper to arXiv:1308.6103. To appear in Handbook of Operator Theory, Springe

    An Institutional Theory perspective on sustainable practices across the dairy supply chain

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    AbstractThe need for sustainable practices in the food supply chain, particularly in the area of energy reduction, is becoming acute. The food industry currently has to contend with multiple competing pressures alongside the new challenges of sustainable production. We applied Institutional Theory to explore the role of supermarkets in the development of legitimate sustainable practices across the dairy supply chains. The paper focuses on dairy supply chain organizations and their consumption of energy. We conducted 70 semi-structured telephone interviews with various stakeholders across the supply chain. Findings revealed that the majority of actors in the supply chain identified supermarkets as the dominant player, and that the supermarkets exert pressure on other smaller organizations across the supply chain. Although some organizations wished to pursue a sustainable agenda through integrating new rules and legitimate practices within their own organization, the dominant logic appeared to be one of cost reduction and profit maximization. There was also evidence that supermarkets and other large organizations attempt to replicate publicly available information on green successes for image purposes. We conclude that the dominant logic of cost reduction is so well established that challenging the dominant logic may prove difficult. The challenge is therefore to complement the dominant logic with sustainable practices across the whole supply chain, a role Government needs to play. This will require a broader more systemic approach to encouraging sustainable practices including investment and financing practices, so that all members of the dairy supply chain can co-operate and contribute to energy reduction

    Measurement of three-jet differential cross sections d sigma-3jet / d M-3jet in p anti-p collisions at sqrt(s)=1.96 TeV

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    We present the first measurement of the inclusive three-jet differential cross section as a function of the invariant mass of the three jets with the largest transverse momenta in an event in p anti-p collisions at sqrt(s) = 1.96 TeV. The measurement is made in different rapidity regions and for different jet transverse momentum requirements and is based on a data set corresponding to an integrated luminosity of 0.7 fb^{-1} collected with the D0 detector at the Fermilab Tevatron Collider. The results are used to test the three-jet matrix elements in perturbative QCD calculations at next-to-leading order in the strong coupling constant. The data allow discrimination between parametrizations of the parton distribution functions of the proton.Comment: 10 pages, 4 figures, 2 tables, submitted to Phys. Lett. B, corrected chi2 values for NNPD

    A measurement of the tau mass and the first CPT test with tau leptons

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    We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV using tau pairs from Z0 decays. To test CPT invariance we compare the masses of the positively and negatively charged tau leptons. The relative mass difference is found to be smaller than 3.0 10^-3 at the 90% confidence level.Comment: 10 pages, 4 figures, Submitted to Phys. Letts.

    Measurement of the B0 Lifetime and Oscillation Frequency using B0->D*+l-v decays

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    The lifetime and oscillation frequency of the B0 meson has been measured using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP. The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the production flavour of the B0 mesons was determined using a combination of tags from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d = 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first error is statistical and the second systematic.Comment: 17 pages, 4 figures, submitted to Phys. Lett.

    First Measurement of Z/gamma* Production in Compton Scattering of Quasi-real Photons

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    We report the first observation of Z/gamma* production in Compton scattering of quasi-real photons. This is a subprocess of the reaction e+e- to e+e-Z/gamma*, where one of the final state electrons is undetected. Approximately 55 pb-1 of data collected in the year 1997 at an e+e- centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been analysed. The Z/gamma* from Compton scattering has been detected in the hadronic decay channel. Within well defined kinematic bounds, we measure the product of cross-section and Z/gamma* branching ratio to hadrons to be (0.9+-0.3+-0.1) pb for events with a hadronic mass larger than 60 GeV, dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60 GeV, dominated by (e)egamma* production, this product is found to be (4.1+-1.6+-0.6) pb. Our results agree with the predictions of two Monte Carlo event generators, grc4f and PYTHIA.Comment: 18 pages, LaTeX, 5 eps figures included, submitted to Physics Letters

    Search for Higgs Bosons in e+e- Collisions at 183 GeV

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    The data collected by the OPAL experiment at sqrts=183 GeV were used to search for Higgs bosons which are predicted by the Standard Model and various extensions, such as general models with two Higgs field doublets and the Minimal Supersymmetric Standard Model (MSSM). The data correspond to an integrated luminosity of approximately 54pb-1. None of the searches for neutral and charged Higgs bosons have revealed an excess of events beyond the expected background. This negative outcome, in combination with similar results from searches at lower energies, leads to new limits for the Higgs boson masses and other model parameters. In particular, the 95% confidence level lower limit for the mass of the Standard Model Higgs boson is 88.3 GeV. Charged Higgs bosons can be excluded for masses up to 59.5 GeV. In the MSSM, mh > 70.5 GeV and mA > 72.0 GeV are obtained for tan{beta}>1, no and maximal scalar top mixing and soft SUSY-breaking masses of 1 TeV. The range 0.8 < tanb < 1.9 is excluded for minimal scalar top mixing and m{top} < 175 GeV. More general scans of the MSSM parameter space are also considered.Comment: 49 pages. LaTeX, including 33 eps figures, submitted to European Physical Journal
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