Among patients with unstable angina or myocardial infarction without ST-segment elevation, prasugrel did not significantly reduce the frequency of the primary end point, as compared with clopidogrel, and similar risks of bleeding were observed. (Funded by Eli Lilly and Daiichi Sankyo; TRILOGY ACS ClinicalTrials.gov number, NCT00699998.).

This paper reports comprehensive and accurate measurements of the speed of sound in pure n-butane in the liquid region. The measurements were carried out by a double-path-length pulse-echo technique and cover the temperature range between 200 and 430 K with pressures up to 100 MPa. The expanded uncertainties (at the 95% confidence level) are 2.1 mK for temperature, 0.007% for pressure, and 0.016% for speed of sound. Comparisons with several equations of state and literature data demonstrate that the Helmholtz energy formulation for n-butane can be improved significantly with our accurate data.

Comprehensive and accurate measurements of the speed of sound in liquid n-pentane and isopentane were carried with a double-path-length pulse-echo instrument. The measurements cover the temperature ranges between 200 and 420 K for n-pentane and between 220 and 420 K for isopentane with pressures up to 100 MPa. The expanded uncertainties (at the 0.95 confidence level) are 2.1 mK for temperature, 0.005% for pressure, between 0.01% at low pressure and 0.008% at high pressure for the speed of sound in n-pentane, and between 0.014% at low pressure and 0.01% at high pressure for the speed of sound in isopentane. At high temperatures and low pressure, the uncertainty in the speed of sound in n-pentane increases up to 0.026% at 420 K, while for isopentane it reaches 0.04%. In isopentane, strong damping of the sound signals was observed at temperatures below 260 K, which indicated dispersion of the sound waves in the frequency range of our measurements near 8 MHz. Measured speeds of sound in this temperature range were corrected for dispersion effects to the thermodynamic speed of sound at zero frequency by using information on the sound attenuation in isopentane from the literature. Due to the high damping at low temperatures, the uncertainty in the speed of sound in isopentane amounts to 0.022% at some state points on the isotherm 220 K.

Comprehensive and accurate measurements of the speed of sound in pure ethane have been carried out in the liquid and supercritical regions by a double-path-length pulse-echo technique. The measured data cover the temperature range from 240 K to 420 K with pressures up to 100 MPa. The expanded measurement uncertainties at the 95 % confidence level amount to 2.1 mK for temperature, 0.007 % for pressure, and 0.01 % for speed of sound with the exception of a few state points in the vicinity of the critical point, where the uncertainty increases up to 0.016 %. The quality of the measurements is demonstrated by comparisons with literature data and the fundamental equation of state for ethane

Optical frequency domain imaging (OFDI) was utilized to compare the prevalence of neoatherosclerosis (NA) and morphological characteristics of the neointimal tissue in second generation drug eluting stent (G2-DES)-treated lesions between early (<1 year, E-ISR) and late (>1 year, L-ISR) in-stent restenotic phases. Data comparing NA and in vivo tissue characteristics between early and late in-stent restenosis (ISR) after implantation of G2-DES is limited. An OFDI analysis was performed in 50 G2-DESs {35 everolimus-eluting stent [22 cobalt-chromium (CoCr), 13 platinum-chromium (PtCr)], and 15 biolimus-eluting stent [BES]} ISR lesions (46 consecutive patients) undergoing target lesion revascularization, classified as E-ISR (n = 22 lesion) and L-ISR (n = 28 lesion). NA, defined as a neointima formation containing lipids or calcification was observed in fewer than half (24/50) of all ISR lesions with no significant difference between E-ISR and L-ISR lesions (50 vs. 46.4%, p = 0.8). There were also no significant differences in the morphological appearance and tissue characteristics between E-ISR and L-ISR lesions. ISR was more likely to occur earlier [median 8.6 (8.3-8.9) months] after PtCr-EES implantations (12 lesions vs. 1, p < 0.001), while 3/4 of the BES ISR lesions and more than 2/3 of the CoCr-EES ISR lesions were observed after 1 year of implantation [median 21.3 (20.7-27.5) months, p < 0.001]. Acknowledging some limitations, our observations may suggest that the prevalence of neoatherosclerosis and the morphological appearance, and tissue characteristics of G2-DESs restenotic lesions are similar between the early and late restenotic phases. Certain platforms (PtCr-EESs) may have preferentially presented with early ISR.

An eighth-order virial equation of state (VEOS) for krypton, valid for temperatures up to 5000 K, was developed using the accurate potential functions proposed by Jäger et al. [J. Chem. Phys. 144, 114304 (2016)] for the pair interactions and nonadditive three-body interactions between krypton atoms. While the second and third virial coefficients were already calculated by Jäger et al., the fourth- to eighth-order coefficients were determined in the present work. A simple analytical function was fitted individually to the calculated values of each virial coefficient to obtain the VEOS in an easy-to-use analytical form. To enable a stringent test of the quality of the new VEOS, we measured the speed of sound in krypton in the temperature range from 200 K to 420 K and at pressures up to 100 MPa with a very low uncertainty (at the 0.95 confidence level) of 0.005%–0.018% employing the pulse-echo technique. In order to verify that the isotopic composition of the krypton sample conforms to that of natural krypton in air, high-precision measurements of krypton isotope ratios using a high-sensitivity noble gas mass spectrometer were performed. The extensive comparison with the new speed-of-sound data as well as with experimental p-ρ-T and speed-of-sound data from the literature indicates that pressures and speeds of sound calculated using our new VEOS have uncertainties (at the 0.95 confidence level) of less than 0.1% at state points at which the VEOS is sufficiently converged.

This article reports comprehensive and accurate measurements of the speed of sound in liquid isobutane. The measurements were carried out by a double-path-length pulse-echo technique and cover the temperature range between 200 and 420 K with pressures of up to 100 MPa. The expanded measurement uncertainties (at the 0.95 confidence level) are 2.1 mK for temperature, 0.007% for pressure, and 0.009% for the speed of sound with the exception of a few state points at low pressures and in the vicinity of the critical point, where it increases up to 0.035%. Furthermore, densities and specific isobaric and isochoric heat capacities were derived from the speed-of-sound data in the temperature range between 200 and 340 K and up to 100 MPa by the method of thermodynamic integration. Very accurate results for the derived properties were obtained by determining values of the isobaric heat capacity on the initial isobar for the integration by a well-known thermodynamic relation among the isobaric heat capacity, density, and speed of sound from very accurate density data at low pressures of (Glos, S.; Kleinrahm, R.; Wagner, W. J. Chem. Thermodyn. 2004, 36, 1037−1059) and our speed-of-sound data. Moreover, these initial values were manually adjusted to enforce physically correct behavior of the calculated derivatives of the equation of state. Comparisons of the experimental speeds of sound and derived properties with the Helmholtz energy formulation of Bucker and Wagner for isobutane (Bucker, D.; Wagner, W. J. Phys. Chem. Ref. Data 2006Data , 35, 929−1019 and data from the literature demonstrate the high accuracy of the results and reveal potential to improve the formulation.

The method of thermodynamic integration is applied to calculate accurate data for the density and isobaric and isochoric heat capacity of toluene and n-butane from speed of sound data sets measured previously in our laboratory. Values for the density and isobaric heat capacity on the initial isobar for the integration are derived from very accurate density and speed of sound data sets using well-known thermodynamic relations. The relative expanded uncertainties (at the 0.95 confidence level) in the derived values for the density and isobaric and isochoric heat capacities are estimated to be 0.011 %, 0.3 %, and 0.4 % for toluene and 0.02 %, 0.5 %, and 0.7 % for n-butane, respectively. Comparisons with experimental data, values of other authors derived by the thermodynamic integration, and equations of state show that our values for both fluids are more accurate than most data available in the literature. Moreover, the domain of the thermodynamic integration for toluene extends down to 240 K and covers lower temperatures than recently considered by other authors. The derived values for the isobaric heat capacity of n-butane fill a gap as this property has hitherto only been measured at ambient pressure. Because of their low uncertainty, the values of the derived properties reported in this work in combination with recent data of other authors are useful for developing new and improved equations of state for both fluids.