Silage Making and Silage Additives

Silage formation should be considered a self-preservation of a feedstuff by fermentation of some of its nutrients by enzymes present in and/or organisms already present on the feedstuff. The resulting product has been defined as a feedstuff resulting from anaerobic fermentation of moist forage or other feedstuff and by preservation with the formation of acids. Even under ideal conditions of silage formation, nutrient losses will occur during the fermentation process. The discussion which follows will include suggestions and criteria for making high quality silage with minimum loss of nutrients

Performance of a commercial wine store with insulated concrete walls

The internal environment within an unconditioned wine barrel store, constructed from insulated concrete panels and located in south-eastern Australia, has been investigated during a summer and winter month. Average temperatures inside the store were found to be 13.7&deg;C and 22.8&deg;C in the winter and summer month respectively. A validated mathematical model of the store was used to investigate the contribution of the concrete walls, insulation and the wine itself to the internal thermal environment. The concrete walls were found to be the least influential.<br /

Ground state phases of the Half-Filled One-Dimensional Extended Hubbard Model

Using quantum Monte Carlo simulations, results of a strong-coupling expansion, and Luttinger liquid theory, we determine quantitatively the ground state phase diagram of the one-dimensional extended Hubbard model with on-site and nearest-neighbor repulsions U and V. We show that spin frustration stabilizes a bond-ordered (dimerized) state for U appr. V/2 up to U/t appr. 9, where t is the nearest-neighbor hopping. The transition from the dimerized state to the staggered charge-density-wave state for large V/U is continuous for U up to appr. 5.5 and first-order for higher U.Comment: 4 pages, 4 figure

Direct observation of the multiple spin gap excitations in two-dimensional dimer system SrCu2(BO3)2

Various spin gap excitations have been observed in the two-dimensional dimer system SrCu_2(BO_3)_2 by means of submillimeter wave ESR. The zero-field energy gap of the lowest spin gap excitation shows a splitting into two triplet modes and the energy splitting clearly depends on the magnetic field orientation when a field is rotated in the {\mib {ac}}-plane. A zero-field splitting is also found between the S(_z)=+1 and S(_z)=-1 branches of each triplet. These behaviors are qualitatively explained by considering the anisotropic exchange coupling of inter-dimer and intra-dimer, respectively. The averaged value of the lowest spin gap energy is determined to be 722 \pm 2 GHz(34.7 K). We have also found the second spin gap excitation at 1140 GHz(54.7 K), which indicates that the inter-dimer coupling is significantly strong. Besides these modes, a number of gapped ESR absorption are found and we propose that these multiple magnetic excitations are caused by the localized nature of the excited state in the present system.Comment: 4pages 4figure

Numerical Evidence for Multiplicative Logarithmic Corrections from Marginal Operators

Field theory calculations predict multiplicative logarithmic corrections to correlation functions from marginally irrelevant operators. However, for the numerically most suitable model - the spin-1/2 chain - these corrections have been controversial. In this paper, the spin-spin correlation function of the antiferromagnetic spin-1/2 chain is calculated numerically in the presence of a next nearest neighbor coupling J2 for chains of up to 32 sites. By varying the coupling strength J2 we can control the effect of the marginal operator, and our results unambiguously confirm the field theory predictions. The critical value at which the marginal operator vanishes has been determined to be at J2 = 0.241167 +/- 0.000005J.Comment: revised paper with extended data-analysis. 5 pages, using revtex with 4 embedded figures (included with macro). A complete postscript file with all figures + text (5 pages) is available from http://FY.CHALMERS.SE/~eggert/marginal.ps or by request from [email protected]

Disorder Induced Quantum Phase Transition in Random-Exchange Spin-1/2 Chains

We investigate the effect of quenched bond-disorder on the anisotropic spin-1/2 (XXZ) chain as a model for disorder induced quantum phase transitions. We find non-universal behavior of the average correlation functions for weak disorder, followed by a quantum phase transition into a strongly disordered phase with only short-range xy-correlations. We find no evidence for the universal strong-disorder fixed point predicted by the real-space renormalization group, suggesting a qualitatively different view of the relationship between quantum fluctuations and disorder.Comment: 4 pages, 4 postscript figures, needs RevTeX

Kleptoparasitic melees--modelling food stealing featuring contests with multiple individuals

Kleptoparasitism is the stealing of food by one animal from another. This has been modelled in various ways before, but all previous models have only allowed contests between two individuals. We investigate a model of kleptoparasitism where individuals are allowed to fight in groups of more than two, as often occurs in real populations. We find the equilibrium distribution of the population amongst various behavioural states, conditional upon the strategies played and environmental parameters, and then find evolutionarily stable challenging strategies. We find that there is always at least one ESS, but sometimes there are two or more, and discuss the circumstances when particular ESSs occur, and when there are likely to be multiple ESSs

Higher Daptomycin Dose Associated with Improved Survival in Methicillin-Resistant Staphylococcus aureus Bacteremia

Study Objective: Current guidelines recommend higher daptomycin doses than the daptomycin label dose of 6 mg/kg for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia; however, the evidence supporting this recommendation is from in vitro and case series studies. This study evaluated the comparative effectiveness of the daptomycin label dose versus higher daptomycin doses in patients with MRSA bacteremia. Design: Retrospective national cohort study. Setting: Veterans Affairs medical centers. Patients: A total of 371 adults with MRSA bacteremia who were admitted between 2002 and 2015 and treated initially with vancomycin within 24 hours of initial culture collection and then switched to daptomycin therapy within 7 days; 138 patients (37.2%) received daptomycin doses higher than the daptomycin label dose (7 mg/kg or greater), and 233 (62.8%) received the daptomycin label dose (6 mg/kg). Measurements and Main Results: Clinical outcomes were compared among those who received the daptomycin label dose and those who received the higher dose using propensity score–matched Cox proportional hazards regression models. To identify dose partitioning associated with optimal survival, classification and regression tree (CART) analysis was used among patients, controlling for confounding with a 30-day mortality disease risk score. Propensity score–matched 30-day mortality was 8.6% (6/70 patients) among the higher dose group versus 18.6% (13/70 patients) among the label dose group (hazard ratio 0.31, 95% confidence interval 0.10–0.94). No significant differences were observed in inpatient mortality, length of stay, 30-day readmission, or 30-day S. aureus reinfection between groups. CART analysis resulted in doses of 7 mg/kg or greater providing benefit only among patients with higher (more than 51%) predicted probabilities of 30-day mortality (p\u3c0.001). Conclusion: To our knowledge, this is the first comparative effectiveness study of daptomycin doses in patients with MRSA bacteremia. Survival benefits were observed with doses higher than the daptomycin label dose (7 mg/kg or greater) for the treatment of MRSA bacteremia. These data suggest that higher doses than the daptomycin label dose may be preferred over the label dose for improving clinical outcomes in patients with MRSA bacteremia

Antiferromagnetic Heisenberg chains with bond alternation and quenched disorder

We consider S=1/2 antiferromagnetic Heisenberg chains with alternating bonds and quenched disorder, which represents a theoretical model of the compound CuCl_{2x}Br_{2(1-x)}(\gamma-{pic})_2. Using a numerical implementation of the strong disorder renormalization group method we study the low-energy properties of the system as a function of the concentration, x, and the type of correlations in the disorder. For perfect correlation of disorder the system is in the random dimer (Griffiths) phase having a concentration dependent dynamical exponent. For weak or vanishing disorder correlations the system is in the random singlet phase, in which the dynamical exponent is formally infinity. We discuss consequences of our results for the experimentally measured low-temperature susceptibility of CuCl_{2x}Br_{2(1-x)}(\gamma-{pic})_2