Simple Local Computation Algorithms for the General Lovasz Local Lemma

We consider the task of designing Local Computation Algorithms (LCA) for applications of the Lov\'{a}sz Local Lemma (LLL). LCA is a class of sublinear algorithms proposed by Rubinfeld et al.~\cite{Ronitt} that have received a lot of attention in recent years. The LLL is an existential, sufficient condition for a collection of sets to have non-empty intersection (in applications, often, each set comprises all objects having a certain property). The ground-breaking algorithm of Moser and Tardos~\cite{MT} made the LLL fully constructive, following earlier results by Beck~\cite{beck_lll} and Alon~\cite{alon_lll} giving algorithms under significantly stronger LLL-like conditions. LCAs under those stronger conditions were given in~\cite{Ronitt}, where it was asked if the Moser-Tardos algorithm can be used to design LCAs under the standard LLL condition. The main contribution of this paper is to answer this question affirmatively. In fact, our techniques yield LCAs for settings beyond the standard LLL condition

Multicenter Validation of the Vasoactive-Ventilation-Renal Score as a Predictor of Prolonged Mechanical Ventilation After Neonatal Cardiac Surgery

Objectives: We sought to validate the Vasoactive-Ventilation-Renal score, a novel disease severity index, as a predictor of outcome in a multicenter cohort of neonates who underwent cardiac surgery. Design: Retrospective chart review. Setting: Seven tertiary-care referral centers. Patients: Neonates defined as age less than or equal to 30 days at the time of cardiac surgery. Interventions: Ventilation index, Vasoactive-Inotrope Score, serum lactate, and Vasoactive-Ventilation-Renal score were recorded for three postoperative time points: ICU admission, 6 hours, and 12 hours. Peak values, defined as the highest of the three measurements, were also noted. Vasoactive-Ventilation-Renal was calculated as follows: ventilation index + Vasoactive-Inotrope Score + Δ creatinine (change in creatinine from baseline × 10). Primary outcome was prolonged duration of mechanical ventilation, defined as greater than 96 hours. Receiver operative characteristic curves were generated, and abilities of variables to correctly classify prolonged duration of mechanical ventilation were compared using area under the curve values. Multivariable logistic regression modeling was also performed. Measurements and Main Results: We reviewed 275 neonates. Median age at surgery was 7 days (25th–75th percentile, 5–12 d), 86 (31%) had single ventricle anatomy, and 183 (67%) were classified as Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery Congenital Heart Surgery Mortality Category 4 or 5. Prolonged duration of mechanical ventilation occurred in 89 patients (32%). At each postoperative time point, the area under the curve for prolonged duration of mechanical ventilation was significantly greater for the Vasoactive-Ventilation-Renal score as compared to the ventilation index, Vasoactive-Inotrope Score, and serum lactate, with an area under the curve for peak Vasoactive-Ventilation-Renal score of 0.82 (95% CI, 0.77–0.88). On multivariable analysis, peak Vasoactive-Ventilation-Renal score was independently associated with prolonged duration of mechanical ventilation, odds ratio (per 1 unit increase): 1.08 (95% CI, 1.04–1.12). Conclusions: In this multicenter cohort of neonates who underwent cardiac surgery, the Vasoactive-Ventilation-Renal score was a reliable predictor of postoperative outcome and outperformed more traditional measures of disease complexity and severity

Variational Approach to Gaussian Approximate Coherent States: Quantum Mechanics and Minisuperspace Field Theory

This paper has a dual purpose. One aim is to study the evolution of coherent states in ordinary quantum mechanics. This is done by means of a Hamiltonian approach to the evolution of the parameters that define the state. The stability of the solutions is studied. The second aim is to apply these techniques to the study of the stability of minisuperspace solutions in field theory. For a $\lambda \varphi^4$ theory we show, both by means of perturbation theory and rigorously by means of theorems of the K.A.M. type, that the homogeneous minisuperspace sector is indeed stable for positive values of the parameters that define the field theory.Comment: 26 pages, Plain TeX, no figure

Time Evolution of Spin Waves

A rigorous derivation of macroscopic spin-wave equations is demonstrated. We introduce a macroscopic mean-field limit and derive the so-called Landau-Lifshitz equations for spin waves. We first discuss the ferromagnetic Heisenberg model at T=0 and finally extend our analysis to general spin hamiltonians for the same class of ferromagnetic ground states.Comment: 4 pages, to appear in PR

Effects of branched chain amino acids on sow and litter performance

Three hundred-six sows were used to evaluate effects of the interrelationship among valine, isoleucine, and leucine on sow and litter performance. Eight dietary treatments were arranged as a 2x2x2 factorial with two levels of valine (.80 and 1.20%), isoleucine (.68 and 1.08%), and leucine (1.57 and 1.97%). Litter weaning weight, litter weight gain from d 2 to weaning, and sow backfat loss increased as dietary valine increased but were not affected by dietary isoleucine or leucine. Increasing dietary valine, isoleucine, or leucine did not affect milk fat, DM, CP, or lactose. These results confirm the importance of dietary valine for increased litter weaning weight, independent of either additional dietary isoleucine or leucine.; Swine Day, Manhattan, KS, November 19, 199

Effects of branched chain amino acids on sow and litter performance

Three hundred-six sows were used to evaluate effects of the interrelationship among valine, isoleucine, and leucine on sow and litter performance. Eight dietary treatments were arranged as a 2x2x2 factorial with two levels of valine (.80 and 1.20%), isoleucine (.68 and 1.08%), and leucine (1.57 and 1.97%). Litter weaning weight, litter weight gain from d 2 to weaning, and sow backfat loss increased as dietary valine increased but were not affected by dietary isoleucine or leucine. Increasing dietary valine, isoleucine, or leucine did not affect milk fat, DM, CP, or lactose. These results confirm the importance of dietary valine for increased litter weaning weight, independent of either additional dietary isoleucine or leucine.; Swine Day, Manhattan, KS, November 19, 199

Non-universal exponents in interface growth

We report on an extensive numerical investigation of the Kardar-Parisi-Zhang equation describing non-equilibrium interfaces. Attention is paid to the dependence of the growth exponents on the details of the distribution of the noise. All distributions considered are delta-correlated in space and time, and have finite cumulants. We find that the exponents become progressively more sensitive to details of the distribution with increasing dimensionality. We discuss the implications of these results for the universality hypothesis.Comment: 12 pages, 5 figures; to appear in Phys. Rev. Let