stable crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reactionbetween hydantoins or thiohydantoins and dialkyl acetylenedicarboxylates in the presence oftriphenylphosphine. these phosphoranes undergo smooth intramolecular wittig reaction followedby an electrocyclic ring opening to produce dialkyl (e)-2-(2,5-dihydro-5,5-diaryl-2-thioxo-1h-imidazol-4-yl)fum...

In 1969, Roger Penrose proposed a mechanism to extract rotational energy from Kerr black hole. With this, he inspired two lines of investigation in the years after. On one side, process, as it became known, allowed comparison between black-hole mechanics and thermodynamics. other, opened path quantum description those objects. This paper provides novel take on events that led rise thermodynamic...

The ability to determine one's location is fundamental to spatial navigation. Here, it is shown that localization is theoretically possible without the use of external cues, and without knowledge of initial position or orientation. With only error-prone self-motion estimates as input, a fully disoriented agent can, in principle, determine its location in familiar spaces with 1-fold rotational s...

Microwave and far-infrared spectra of the H, N-HOH dimer have been recorded from 36 to 86 GHz and 520 to 800 GHz with a planar supersonic jet/tunable laser sideband spectrometer. The a-type pure rotational microwave data extend the previous m = 0, K = 0 A symmetry manifold measurements of Herbine and Dyke [J. Chem. Phys. 83, 3768 ( 1980) ] to higher frequency and also provide an additional set ...

Thousands of cardiac failure patients per year in the United States could benefit from long-term mechanical circulatory support as destination therapy. To provide an improvement over currently available devices, we have designed a fully implantable axial-flow ventricular assist device with a magnetically levitated impeller (LEV-VAD). In contrast to currently available devices, the LEV-VAD has a...

We consider a two-dimensional convection model augmented with the rotational Coriolis forcing, Ut + U · ∇xU = 2kU, with a fixed 2k being the inverse Rossby number. We ask whether the action of dispersive rotational forcing alone, U, prevents the generic finite time breakdown of the free nonlinear convection. The answer provided in this work is a conditional yes. Namely, we show that the rotatin...

A detailed study of the three-dimensional sound fields around a monopole point source in subsonic and supersonic rotation is investigated. We calculate pressure, acoustic velocity, as well instantaneous time-averaged intensity with advanced time approach. The approach applied for sources at yield comparable results those obtained from spherical harmonic series expansion method or solution retar...

Study Design We present a patient-specific computer model created to translate two-dimensional (2D) fluoroscopic motion data into three-dimensional (3D) in vivo biomechanical motion data. Objective The aim of this study is to determine the in vivo biomechanical differences in patients with and without acute low back pain. Current dynamic imaging of the lumbar spine consists of flexion-extension...

The objective of this lecture is to review the basic building blocks of lumped parameter rotational mechanical systems and to build the foundations that will enable you to model more complex dynamic systems consisting of translation and rotational elements. Corresponding to the translational elements mass, spring and damper, are the rotational inertia, rotational spring and rotational damper, r...

In this paper, we first introduce the definition of rotational sets for cellular automata ∞ using Misiurewicz’s rotational sets. After that, we define rotational entropy functions for cellular automata ∞ from Bowen’s definiton of rotational entropy. Finally, we compare rotational entropy function with topologic entropy function for cellular automata ∞.