The interference modulated transmission spectra T( lambda ) at normal incidence for amorphous arsenic sulphide semiconducting films deposited by thermal evaporation were obtained in the spectral region from 300 nm up to 2000 nm. The straightforward analysis proposed by Swanepoel (1983), which is based on the use of the extremes of the interference fringes, has been applied in order to derive the real and imaginary parts of the complex index of refraction and also the film thickness. Thickness measurements made by a surface profiling stylus have also been carried out to cross check the results obtained by the method employing only T( lambda ). In addition, the optical band gap Egopt has been determined from the absorption coefficient values using Tauc's procedure, i.e. from the relationship alpha (h nu )=K(h nu -Egopt)2/h nu , where K is a constant. Finally, it is emphasised that accurate results were achieved not only with the above mentioned glass composition As2S3, but also in the case of the non-stoichiometric composition As30S70.

Writing Committee on behalf of the COM99 Study Group* Background-Medication nonadherence is common and results in preventable disease complications. This study assessed the effectiveness of a multifactorial intervention to improve both medication adherence and blood pressure control and to reduce cardiovascular events. Methods and Results-In this multicenter, cluster-randomized trial, physicians from hospital-based hypertension clinics and primary care centers across Spain were randomized to receive and provide the intervention to their high-risk patients. Eligible patients were Ն50 years of age, had uncontrolled hypertension, and had an estimated 10-year cardiovascular risk greater than 30%. Physicians randomized to the intervention group counted patients' pills, designated a family member to support adherence behavior, and provided educational information to patients. The primary outcome was blood pressure control at 6 months. Secondary outcomes included both medication adherence and a composite end point of all-cause mortality and cardiovascular-related hospitalizations. Seventy-nine physicians and 877 patients participated in the trial. The mean duration of follow-up was 39 months. Intervention patients were less likely to have an uncontrolled systolic blood pressure (odds ratio 0.62, 95% confidence interval 0.50 to 0.78) and were more likely to be adherent (odds ratio 1.91, 95% confidence interval 1.19 to 3.05) than control group patients at 6 months. After 5 years, 16% of the patients in the intervention group and 19% in the control group met the composite end point (hazard ratio 0.97, 95% confidence interval 0.67 to 1.39). Conclusions-A multifactorial intervention to improve adherence to antihypertensive medication was effective in improving both adherence and blood pressure control, but it did not appear to improve long-term cardiovascular events. Clinical Trial Registration-URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35208258. Key Words: hypertension Ⅲ medication adherence Ⅲ blood pressure Ⅲ intervention studies H ypertension is a major but modifiable contributory factor to cardiovascular diseases such as stroke and coronary heart disease. 1,2 According to the Seventh Report of the Joint National Committee on Prevention, Detection, and Treatment of High Blood Pressure in the United States, the percentage of patients whose blood pressure (BP) is under control (ie, Ͻ140/90 mm Hg) increased from 10% in 1976 -1980 to 34% in the period 1999 -2000.Continuing medical education (CME) credit is available for this article. Go to http://cme.ahajournals.org to take the quiz. Received October 30, 2009; accepted July 14, 2010 Editorial see p 1141 Clinical Perspective on p 1191A major modifiable reason for the lack of BP control is medication nonadherence, where adherence is defined as the extent to which a person's behavior corresponds with the recommendations of their healthcare provider. 7 In general, poor adherence to medications is associated with the development of complications, disease pr...

The role played by a glass substrate on the accurate determination of the optical constants and the thickness of a thin dielectric film deposited on it, when well-known envelope methods are used, is discussed. Analytical expressions for the two envelopes of the optical transmission spectra corresponding to film. with both uniform and nonuniform thicknesses are derived, assuming the substrate to be a weakly absorbing layer. It is shown that accurate determination of the refractive index and the film thickness is notably improved when the absorption of the substrate is considered. The analytical expressions for the upper and lower envelope, are used to characterize optically and geometrically both uniform and nonuniform amorphous chalcogenide films. The results obtained are compared with those derived by use of expressions for the envelopes that neglect the substrate absorption. The comparison shows that overestimated refractive indexes and underestimated thicknesses are obtained when the conventional approach, in which the substrate absorption is neglected, is used.

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Optical-transmission spectra are very sensitive to inhomogeneities in thin ®lms. In particular, a non-uniform thickness produces a clear shrinking in the transmission spectrum at normal incidence. If this deformation is not taken into account, it may lead to serious errors in the calculated values of the refractive index and ®lm thickness. In this paper, a method ®rst applied by Swanepoel for enabling the transformation of an optical-transmission spectrum of a thin ®lm of wedge-shaped thickness into the spectrum of a uniform ®lm, whose thickness is equal to the average thickness of the non-uniform layer, has been employed. This leads subsequently to the accurate derivation of the refractive index in the subgap region (0.1±1.8 eV), the average thickness, as well as a parameter indicating the degree of ®lmthickness uniformity. This optical procedure is applied to the particular case of freshly-prepared ®lms of the Ge 10 As 15 Se 75 ternary chalcogenide glassy alloy. The dispersion of the refractive index is discussed in terms of the Wemple±DiDomenico single-oscillator model. The optical-absorption edge is described using the`non-direct transition' model proposed by Tauc, and the optical energy gap is calculated by Tauc's extrapolation. Finally, the photo-induced and thermally induced changes in the optical properties of the aGe 10 As 15 Se 75 layers are also studied.