248 research outputs found

    Effect of starch level and roughage intake on animal perfomance, rumen wall characteristics and liver abscesses in intensively fed Frisian bulls

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    Organic dairy cows in Denmark has a higher frequency of liver abscesses, which is probably due to higher starch levels in the feed rations to high yielding cows compaired to conventional cows. Following abstract is based on experiments on young bulls and demonstrates whether replacing high-starch feeds with low-starch feed, such as dried grass pellets and sugar beet pulp, can reduce the problems with liver abscessation without reducing the performance level. The low-starch feed would be relevant to organic dairy production. In total, 41 Danish Friesian bulls (154±20 kg LW) were allocated into four treatment groups in a 2x2 factorial design fed either a high starch (N) or a high fibrous concentrate (F) and either chopped barley straw (S) or a mixture of 75% chopped barley straw and 25% sugar beet molasses (Sm). In the F ration, 25% of the wheat from N was replaced by dried sugar beet pulp and grass pellets giving a starch level of 24.3% and 39.1% (wt) and an energy content of 0.99 and 1.04 Scandinavian Feed Units/kg feed, respectively. The ad libitum fed bulls were slaughtered at 11.5±0.2 mo. weighing 429±41 kg LW on average. Feed intake was higher for F than N (p=0.005) (7.1 vs. 6.4 kg/d), whereas the addition of molasses increased straw intake from 0.5 to 0.9 kg/d (p<0.001). The higher intake of Sm compared with S reduced concentrate intake (p<0.05), but did not affect total net energy intake. The average daily gain (1370 g/d) did not differ between groups. The rumen wall was more severely damaged with N compared with F (p<0.05) and with S compared with Sm (p<0.003). The higher straw intake prevented rumen wall damage, but did not reduce the number of animals with liver abscesses, like the lower starch level did (1 vs. 9 animals, p<0.005)

    Herbage intake in Danish Jersey and Danish Holstein steers on perennial ryegrass/white clover pasture

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    The objective of this study was to estimate herbage intake in Danish Friesian and Danish Jersey steers at an age of 8-9 months on ryegrass / white clover pasture. The steers were turned out on pasture in late April and herbage intake was estimated in June in steers of a mean live weight (± S.D.) of 264 ± 14 kg and 185 ± 25 kg for Danish Friesian and Danish Jersey respectively. Faeces and herbage samples were analysed for alkanes to estimate herbage dry matter intake, dry matter digestibility (DMD) and botanical composition of intake. The weight gains at the time of herbage intake estimation in June (kg/day) were 1.142 ± 265 kg/day and 0.927 ± 168 kg/day for Danish Friesian and Danish Jersey respectively. Daily herbage intake (kg dry matter (DM)) estimated by alkanes C32 /C33 was 8.33 ± 0.97 and 6.28 ± 0.61 per day (P<0.001) and 3.15 ± 0.32 and 3.43 ± 0.30 per 100 kg liveweight (LW) (P<0.05) for Danish Friesian and Danish Jersey respectively. The botanical composition of the diet was the same for Danish Friesian and Danish Jersey with about half of the diet being grass leaves and the other half clover leaves. It is concluded that Danish Jersey steers have higher herbage intake per 100 kg LW than Danish Friesian steers of the same age, but herbage intake per kg metabolic LW is not different between the two breeds

    Beyond the binary collision approximation for the large-qq response of liquid 4^4He

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    We discuss corrections to the linear response of a many-body system beyond the binary collision approximation. We first derive for smooth pair interactions an exact expression of the response 1/q2\propto 1/q^2, considerably simplifying existing forms and present also the generalization for interactions with a strong, short-range repulsion. We then apply the latter to the case of liquid 4^4He. We display the numerical influence of the 1/q21/q^2 correction around the quasi-elastic peak and in the low-intensity wings of the response, far from that peak. Finally we resolve an apparent contradiction in previous discussions around the fourth order cumulant expansion coefficient. Our results prove that the large-qq response of liquid 4^4He can be accurately understood on the basis of a dynamical theory.Comment: 19 p. Figs. available on reques

    Effects of chicory roots on finishing performance and CLA and fatty acid composition in longissimus muscle of Friesian steers

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    Low profitability is believed to be the greatest hindrance profitability is believed to be the greatest hindrance for a more extensive use of dairy breed bull calves in for a more extensive use of dairy breed bull calves in organic beef production systems organic beef production systems Among certain consumers, there is an increasing interest Among certain consumers, there is an increasing interest for organic beef production for organic beef production However, there is a need for reliable information about However, there is a need for reliable information about and documentation for production parameters, methods and documentation for production parameters, methods for rearing and housing, feeding strategies etc. to be able for rearing and housing, feeding strategies etc. to be able to increase the consumption of beef meat based on dairy to increase the consumption of beef meat based on dairy calves in Denmark calves in Denmark. Specifically, we believe there will be increased focus on Specifically, we believe there will be increased focus on improving animal health and welfare and product quality in improving animal health and welfare and product quality in the steer production systems the steer production systems There will also be a wish from the society and EU to use There will also be a wish from the society and EU to use and preserve the biodiversity of the marginal grazing and preserve the biodiversity of the marginal grazing areas areas The project reported here arises from a larger project The project reported here arises from a larger project investigating the effects of grazing system (set investigating the effects of grazing system (set stocking vs. two stocking vs. two-paddock rotation) for steers and the paddock rotation) for steers and the use of bioactive crops (especially chicory) use of bioactive crops (especially chicory). Chicory is used because of the possible positive Chicory is used because of the possible positive influence on animal health, i.e., parasite control, meat influence on animal health, i.e., parasite control, meat quality and sensory quality of meat from both steers quality and sensory quality of meat from both steers and pigs (including CLA content, selenium and and pigs (including CLA content, selenium and antioxidative antioxidative status, drip loss and boar status, drip loss and boar taint/ taint/androstenone androstenone levels) levels). The overall objective of the entire project was to The overall objective of the entire project was to develop production methods/strategies that could develop production methods/strategies that could improve the quality aspects of organic meat improve the quality aspects of organic meat

    Computing the output distribution and selection probabilities of a stack filter from the DNF of its positive Boolean function

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    Many nonlinear filters used in practise are stack filters. An algorithm is presented which calculates the output distribution of an arbitrary stack filter S from the disjunctive normal form (DNF) of its underlying positive Boolean function. The so called selection probabilities can be computed along the way.Comment: This is the version published in Journal of Mathematical Imaging and Vision, online first, 1 august 201

    A batch-service queueing model with a discrete batch Markovian arrival process

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    Queueing systems with batch service have been investigated extensively during the past decades. However, nearly all the studied models share the common feature that an uncorrelated arrival process is considered, which is unrealistic in several real-life situations. In this paper, we study a discrete-time queueing model, with a server that only initiates service when the amount of customers in system (system content) reaches or exceeds a threshold. Correlation is taken into account by assuming a discrete batch Markovian arrival process (D-BMAP), i.e. the distribution of the number of customer arrivals per slot depends on a background state which is determined by a first-order Markov chain. We deduce the probability generating function of the system content at random slot marks and we examine the influence of correlation in the arrival process on the behavior of the system. We show that correlation merely has a small impact on the threshold that minimizes the mean system content. In addition, we demonstrate that correlation might have a significant influence on the system content and therefore has to be included in the model

    Stability of the doped antiferromagnetic state of the t-t'-Hubbard model

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    The next-nearest-neighbour hopping term t' is shown to stabilize the AF state of the doped Hubbard model with respect to transverse perturbations in the order- parameter by strongly suppressing the intraband particle-hole processes. For a fixed sign of t', this stabilization is found to be significantly different for electron and hole doping, which qualitatively explains the observed difference in the degree of robustness of the AF state in the electron-doped (Nd_{2-x}Ce_{x}CuO_{4}) and hole-doped (La_{2-x}Sr_{x}CuO_{4}) cuprates. The t'-U phase diagram is obtained for both signs of the t' term, showing the different regions of stability and instability of the doped antiferromagnet. Doping is shown to suppress the t'-induced frustration due to the competing interaction J'. A study of transverse spin fluctuations in the metallic AF state reveals that the decay of magnons into particle-hole excitations yields an interesting low-energy result \Gamma \sim \omega for magnon damping.Comment: 10 pages, 8 figure

    The heritability of coronal and sagittal phenotype in idiopathic scoliosis: a report of 12 monozygotic twin pairs

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    Purpose: One of the pathways through which genetics may act in the causation of idiopathic scoliosis is inheritance of a specific sagittal profile that predisposes for its development. In this study, coronal and sagittal parameters were compared in an international collection of monozygotic twins with idiopathic scoliosis. Methods: Twelve monozygotic twin pairs who underwent biplanar radiography for idiopathic scoliosis were systematically identified in existing scoliosis databases in The Netherlands, Sweden, and Denmark. On the first available radiographs, the coronal and sagittal curve parameters (Roussouly and Abelin types, thoracic kyphosis, lumbar lordosis and length of the posteriorly inclined segment) were determined. Results: In all 12 monozygotic twin pairs, both twins were affected by AIS. Four (33%) twin pairs had similar coronal and sagittal spinal phenotype, whereas two (17%) had different coronal phenotype and similar sagittal profiles, and six (50%) pairs had different coronal as well as sagittal phenotype. Conclusions: Analysis of biplanar curve characteristics in monozygotic twins showed that all twin pairs were affected by idiopathic scoliosis. However, only 33% of the pairs had similar coronal and sagittal spinal phenotypes. Based on this limited dataset, the hypothesis can be formulated that besides genetic pre-disposition, the individual (inherited) sagittal profile plays a role in the development of different coronal curve type

    Natural Orbitals and BEC in traps, a diffusion Monte Carlo analysis

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    We investigate the properties of hard core Bosons in harmonic traps over a wide range of densities. Bose-Einstein condensation is formulated using the one-body Density Matrix (OBDM) which is equally valid at low and high densities. The OBDM is calculated using diffusion Monte Carlo methods and it is diagonalized to obtain the "natural" single particle orbitals and their occupation, including the condensate fraction. At low Boson density, na3<105na^3 < 10^{-5}, where n=N/Vn = N/V and aa is the hard core diameter, the condensate is localized at the center of the trap. As na3na^3 increases, the condensate moves to the edges of the trap. At high density it is localized at the edges of the trap. At na3104na^3 \leq 10^{-4} the Gross-Pitaevskii theory of the condensate describes the whole system within 1%. At na3103na^3 \approx 10^{-3} corrections are 3% to the GP energy but 30% to the Bogoliubov prediction of the condensate depletion. At na3102na^3 \gtrsim 10^{-2}, mean field theory fails. At na30.1na^3 \gtrsim 0.1, the Bosons behave more like a liquid 4^4He droplet than a trapped Boson gas.Comment: 13 pages, 14 figures, submitted Phys. Rev.

    The Non-linear Dynamics of Meaning-Processing in Social Systems

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    Social order cannot be considered as a stable phenomenon because it contains an order of reproduced expectations. When the expectations operate upon one another, they generate a non-linear dynamics that processes meaning. Specific meaning can be stabilized, for example, in social institutions, but all meaning arises from a horizon of possible meanings. Using Luhmann's (1984) social systems theory and Rosen's (1985) theory of anticipatory systems, I submit equations for modeling the processing of meaning in inter-human communication. First, a self-referential system can use a model of itself for the anticipation. Under the condition of functional differentiation, the social system can be expected to entertain a set of models; each model can also contain a model of the other models. Two anticipatory mechanisms are then possible: one transversal between the models, and a longitudinal one providing the modeled systems with meaning from the perspective of hindsight. A system containing two anticipatory mechanisms can become hyper-incursive. Without making decisions, however, a hyper-incursive system would be overloaded with uncertainty. Under this pressure, informed decisions tend to replace the "natural preferences" of agents and an order of cultural expectations can increasingly be shaped
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