Hyperbolic chaos in self-oscillating systems based on mechanical triple linkage: Testing absence of tangencies of stable and unstable manifolds for phase trajectories

Dynamical equations are formulated and a numerical study is provided for self-oscillatory model systems based on the triple linkage hinge mechanism of Thurston -- Weeks -- Hunt -- MacKay. We consider systems with holonomic mechanical constraint of three rotators as well as systems, where three rotators interact by potential forces. We present and discuss some quantitative characteristics of the chaotic regimes (Lyapunov exponents, power spectrum). Chaotic dynamics of the models we consider are associated with hyperbolic attractors, at least, at relatively small supercriticality of the self-oscillating modes; that follows from numerical analysis of the distribution for angles of intersection of stable and unstable manifolds of phase trajectories on the attractors. In systems based on rotators with interacting potential the hyperbolicity is violated starting from a certain level of excitation.Comment: 30 pages, 18 figure

Validity of numerical trajectories in the synchronization transition of complex systems

We investigate the relationship between the loss of synchronization and the onset of shadowing breakdown {\it via} unstable dimension variability in complex systems. In the neighborhood of the critical transition to strongly non-hyperbolic behavior, the system undergoes on-off intermittency with respect to the synchronization state. There are potentially severe consequences of these facts on the validity of the computer-generated trajectories obtained from dynamical systems whose synchronization manifolds share the same non-hyperbolic properties.Comment: 4 pages, 4 figure

The CCFM Monte Carlo generator CASCADE 2.2.0

CASCADE is a full hadron level Monte Carlo event generator for ep, \gamma p and p\bar{p} and pp processes, which uses the CCFM evolution equation for the initial state cascade in a backward evolution approach supplemented with off - shell matrix elements for the hard scattering. A detailed program description is given, with emphasis on parameters the user wants to change and variables which completely specify the generated events

Rising drug allergy alert overrides in electronic health records: an observational retrospective study of a decade of experience

Objective There have been growing concerns about the impact of drug allergy alerts on patient safety and provider alert fatigue. The authors aimed to explore the common drug allergy alerts over the last 10 years and the reasons why providers tend to override these alerts. Design: Retrospective observational cross-sectional study (2004–2013). Materials and Methods Drug allergy alert data (n = 611,192) were collected from two large academic hospitals in Boston, MA (USA). Results Overall, the authors found an increase in the rate of drug allergy alert overrides, from 83.3% in 2004 to 87.6% in 2013 (P < .001). Alarmingly, alerts for immune mediated and life threatening reactions with definite allergen and prescribed medication matches were overridden 72.8% and 74.1% of the time, respectively. However, providers were less likely to override these alerts compared to possible (cross-sensitivity) or probable (allergen group) matches (P < .001). The most common drug allergy alerts were triggered by allergies to narcotics (48%) and other analgesics (6%), antibiotics (10%), and statins (2%). Only slightly more than one-third of the reactions (34.2%) were potentially immune mediated. Finally, more than half of the overrides reasons pointed to irrelevant alerts (i.e., patient has tolerated the medication before, 50.9%) and providers were significantly more likely to override repeated alerts (89.7%) rather than first time alerts (77.4%, P < .001). Discussion and Conclusions These findings underline the urgent need for more efforts to provide more accurate and relevant drug allergy alerts to help reduce alert override rates and improve alert fatigue

Limits on Production of Magnetic Monopoles Utilizing Samples from the DO and CDF Detectors at the Tevatron

We present 90% confidence level limits on magnetic monopole production at the Fermilab Tevatron from three sets of samples obtained from the D0 and CDF detectors each exposed to a proton-antiproton luminosity of $\sim175 {pb}^{-1}$ (experiment E-882). Limits are obtained for the production cross-sections and masses for low-mass accelerator-produced pointlike Dirac monopoles trapped and bound in material surrounding the D0 and CDF collision regions. In the absence of a complete quantum field theory of magnetic charge, we estimate these limits on the basis of a Drell-Yan model. These results (for magnetic charge values of 1, 2, 3, and 6 times the minimum Dirac charge) extend and improve previously published bounds.Comment: 18 pages, 17 figures, REVTeX

Heavy quark production via leptoquarks at a neutrino factory

The proposed neutrino factory (NF) based on a muon storage ring (MSR) is an ideal place to look for heavy quark production via neutral current (NC) and charged current (CC) interactions. In this article, we address the issue of contribution coming from mediating leptoquarks (LQ) in $\nu_\mu (\bar\nu_e)-{\rm N}$ interactions leading to the production of $b(\bar b)$ at a MSR and investigate the region where LQ interactions are significant in the near-site experiments.Comment: 12 pages latex, 10 ps figures, uses axocolour.sty, Slightly revised version to appear in PR

Optimization of the Microstructure and Mechanical Properties of a Laves Phase-Strengthened Hypoeutectic NiAl/Cr(Mo,W) Alloy by Suction Casting

A niobium (Nb)-doped NiAl/Cr(Mo,W) hypoeutectic alloy was prepared by conventional and suction casting methods. Its microstructure and compression properties were studied to evaluate the effect of a manufacturing process. A coarse primary NiAl phase and NiAl/Cr(Mo) eutectic cell are demonstrated to be the main components of a NiAl/Cr(Mo,W)–Nb hypoeutectic alloy.Отримано легований ніобієм (Nb) доевтектичний сплав NiAl/Cr(Mo,W) при звичайному литті і литті методом вакуумного всмоктування. Вивчено його мікроструктура і механічні властивості при стиску для оцінки впливу процесу виробництва. Показано, що велика первинна фаза NiAl і евтектична комірка NiAl/Cr(Mo) є основними компонентами сплаву NiAl/Cr(Mo,W) Nb.Получен легированный ниобием (Nb) доэвтектический сплав NiAl/Cr(Mo,W) обычным литьем и литьем методом вакуумного всасывания. Изучены его микроструктура и механические свойства при сжатии для оценки влияния процесса производства. Показано, что крупная первичная фаза NiAl и эвтектическая ячейка NiAl/Cr(Mo) являются основными компонентами сплава NiAl/Cr(Mo,W) Nb

Thermal and viscosity properties of medium- and long-chain triacylglycerol blends

The physical properties of medium- and long-chain triacylglycerol (MLCT) blends were characterized in this study. Blending MLCT oil with either palm olein or soybean oil changed the distribution of fatty acid groups, the crystallization and melting behavior of oil samples, and oil cloudiness. The crystallization and melting curves of both palm olein- and soybean-based MLCT blends showed that the peaks shift to different transition temperatures depending on the percent of MLCT oil added. Viscosity analysis revealed that the oil viscosity was dependent on the temperature and triacylglycerol composition of the oil samples. Blending MLCT oil with either 50% palm olein or 50% soybean oil could assist in preventing crystal growth for the first 8 h of storage at 5 and 0C, respectively

Direct J/psi and psi' hadroproduction via fragmentation in the collinear parton model and k_T-factorization approach

The p_T-spectra for direct J/psi and psi' in hadroproduction at Tevatron energy have been calculated based on NRQCD formalism and fragmentation approximation in the collinear parton model and k_T-factorization approach. We have described the CDF data and obtained a good agreement between the predictions obtained in the parton model and k_T-factorization approach. We performed the calculations using the relevant leading order in alpha_s hard amplitudes and the equal values of the color-octet long-distance matrix elements for the both models.Comment: 10 pages, Latex, 4 eps figures, epsfig.sty, graphics.st