OBJECTIVE To analyze variation in tonsillectomy procedure rates between health care system types around the world. STUDY DESIGN International database analysis. METHODS The 2015 Organization for Economic Co-operation and Development (OECD) Health Statistics surgical procedures database was used to ascertain tonsillectomy procedure volumes for 31 countries. Each country's health system type ...

This international comparison investigates students’ knowledge structure coherence in physics across five countries. In particular, this study investigates two possible hypotheses explaining the conflicting results obtained by Ioannides and Vosniadou (2002) and diSessa, Gillespie, and Esterly (2004) about students’ understandings of force in Greece and the United States. Ioannides and Vosniadou...

The behavior of international stock market returns in terms of rate of return, unconditional volatility, skewness, excess kurtosis, serial dependence and long-memory is examined. A factor analysis approach is employed to identify the underlying dimensions of stock market returns. In our approach, the factors are estimated not from the observed historical returns but from their empirical propert...

In the title compound, C16H20Si, a geometry different from an ideal tetra-hedron can be observed at the Si atom. The bonds from Si to the benzylic C atoms [Si-C = 1.884 (1) and 1.883 (1) Å] are slightly elongated compared to the Si-Cmeth-yl bonds [Si-C = 1.856 (1) and 1.853 (1) Å]. The Cbenz-yl-Si-Cbenz-yl bond angle [C-Si-C = 107.60 (6)°] is decreased from the ideal tetra-hedral angle by 1.9°....

Trends in the growth of extended interstitial defects are extracted from extensive tight-binding and ab inito local density approximation simulations. With an increasing number of interstitials, the stable defect shape evolves from compact to chainlike to rodlike. The rodlike 311 defect, formed from (011) interstitial chains, is stabilized as it grows, elongating in the chain direction. Accurat...

The relations between production and perception in 4-year-old children were examined in a study of compensation strategies for a lip-tube perturbation. Acoustic and perceptual analyses of the rounded vowel [u] produced by twelve 4-year-old French speakers were conducted under two conditions: normal and with a 15-mm-diam tube inserted between the lips. Recordings of isolated vowels were made in ...

this paper describes an optimal design for multivariable pi controller with a high gain structure for an irregular system by genetic algorithm. pi controllers with a high gain structure leads to the asymptotic decomposition of the fast and slow modes in the closed loop system that have unique characteristics. the slow modes are asymptotically uncontrollable and unobservable; therefore, they hav...

Nine isomers of Ge6, Ge6 , Ge6 , and Ge6 6have been searched for by the MP2/6-31+G(d), B3LYP/6-311+G(d), and B3LYP/ LANL2DZ electronic structure calculations. Totally 16 isomers are found: six Ge6, three Ge6 , five Ge6 , and two Ge6 . We discovered that the predicted stable shapes of Ge6 , Ge6 , and Ge6 6are octahedral, pentagonal pyramidal, and hexagonal, respectively, which agrees well with t...