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Thin films of lanthanum monosulfide (LaS) have been deposited on Si (100) substrates by pulsed laser deposition. The films are golden yellow in appearance with a mirrorlike surface morphology and a sheet resistance around 0.1 Ω/□, as measured using a four-probe measurement technique. The thin films are characterized by atomic force microscopy (AFM), x-ray diffraction (XRD) analysis, high resolution transmission electron microscopy (HRTEM), ellipsometry, and Raman spectroscopy. The root-mean-square variation of (1 μm thick) film surface roughness measured over a 1 μm2 area by AFM was found to be 1.74 nm. XRD analysis of fairly thick films (micrometer size) reveals the growth of the cubic rocksalt structure with a lattice constant of 5.863(7) Å, which is close to the bulk LaS value. HRTEM images reveal that the films are comprised of nanocrystals separated by regions of amorphous material. Two beam bright field TEM images show that there is a strain contrast in the Si substrate right under the interface with the LaS film and penetrating into the Si substrate. This suggests that there is an initial epitaxial-like growth of the LaS film on the Si substrate that introduces a strain as a result of the 8% lattice mismatch between the film and substrate. Ellipsometry measurements of the LaS films are well characterized by a Drude-Lorentz model from which an electron concentration of about 2.52×1022 cm-3 and a mobility around 8.5 cm2/V s are derived. Typical crystalline LaS features were evident in Raman spectra of the films, but the spectra also revealed their disordered (polycrystalline) nature. [ABSTRACT FROM AUTHOR]

Slow correlated growth mode in energetic cluster vapor deposited organic light emissive material tris(8-hydroquinoline) aluminum is described. Phase modulated atomic force microscopy has shown very slow grain growth with thickness, with very small phase differences within the film, and fractal dimension calculated from correlation function has shown growth process consistent with diffusion-limited aggregation.

We report slow correlated growth mode in energetic cluster vapor deposited organic light emissive material tris(8-hydroxyquinoline) aluminum from 5 to 100 nm. Phase modulated atomic force microscopy shows very slow grain growth with thickness, with very small phase differences within the film. Fractal dimension calculated from correlation function shows growth process above 10 nm consistent with diffusion-limited aggregation. For low thickness (5 nm), photoluminescence measurement shows the emission peak is shifted by ∼0.4 eV toward lower wavelength. [ABSTRACT FROM AUTHOR]

Objective: To compare the effects of two postmenopausal regimens on menopausal symptoms, bleeding episodes, side effects and acceptability., Design: Double-blind, randomised controlled trial., Setting: Twenty-nine sites in Denmark, nine in Norway and six in Sweden., Participants: Four hundred and thirty-seven postmenopausal women with menopausal complaints. None of these women had had a hysterectomy., Interventions: Daily treatment with tibolone 2.5 mg (n = 218) or 17beta-oestradiol 2 mg plus norethisterone acetate 1 mg (E2/NETA) (n = 219)., Main Outcome Measures: Hot flushes, sweating episodes, vaginal dryness, assessment of sexual life and bleeding patterns; at baseline and after 4, 12, 24 and 48 weeks., Results: Treatment with either preparation significantly reduced mean scores for hot flushes, sweating episodes and vaginal dryness. The overall discontinuation rate was 28% (tibolone 25%, E2/NETA 31%; P = 0.14), mostly during the first six months. There was a markedly lower cumulative incidence of bleeding or spotting episodes with tibolone compared with E2/NETA (P < 0.0001), mainly during the first six treatment cycles., Conclusions: Both tibolone and E2/NETA effectively alleviate menopausal symptoms. However, tibolone caused significantly fewer bleeding or spotting episodes, which were reflected by lower overall rates of bleeding, as well as lower drop-out rates due to bleeding.

The antihypertensive treatment schedules were investigated in 1,153 consecutive patients in 65 general practices. Treatment consisted mainly of diuretics or betablockers singly or combined. In a sample of 303 of these patients, treatment was altered in a randomised, single-blind, cross-over design to consist of a single daily dose of metoprolol, or a single daily dose of metoprolol plus a single dose of a placebo. The effect of multiple dosages on the quality of life was investigated simultaneously with investigation of the efficacy of single drug treatment with a beta-blocker on blood-pressure control as compared with the previous treatment. A slight increase in side-effects was observed which might be ascribed to increased awareness by the patient and also by the doctor. The more simplified regimen with a single daily dose of the betablocker showed the same blood-pressure levels as in the previous more complicated regimen.

For decades, atrial fibrillation was treated exclusively with digoxin. The introduction of Ca-antagonists and beta-blockers has, however, produced valuable alternatives as ventricular function can now be controlled both at rest and during exercise whereas, with digoxin, ventricular function could only be controlled at rest. This review deals with the etiology and electrophysiology of atrial fibrillation together with the effects of Ca-antagonists and beta-blockers on conduction and control of the heart rate during exercise. Documentation of the effects of the different drugs, separately and combined, in the treatment of atrial fibrillation during rest and exercise is presented. It is concluded that alteration in the therapeutic strategy appears reasonable in favour of a combination of digoxin and also Ca-antagonists/beta-blocker.

The quality of life has become an important element in assessment of medicinal treatment. As an independent expression, the quality of life covers the human disappointments which a medical disease may involve ("discomfort") whereas the clinical dysfunction caused by the disease is covered by the expression "disability". In the treatment of essential arterial hypertension, the clinical symptoms of the disease are few or none ("asymptomatic hypertension"). In an investigation of 303 patients in general practice for arterial hypertension, the significance of the frequency of dosage of metoprolol (Seloken) was assessed by means of measurement of the quality of life by the General Health Questionnaire (GHQ), a questionnaire which contains components such as fatigue, sleep, anxiety and depression. No advantages in the quality of life were found in administering antihypertensive drugs once or twice daily. From the methological point of view, the following conditions were found which should be taken into consideration in future investigations in this field: The GHQ was found to be easy for the patients to employ. This is important as the quality of life is a personally experienced dimension. The questionnaire correlated adequately with the visual analogue scales. Approximately 1/3 of the patients had reduced quality of life at the commencement of the investigation as assessed by GHQ. A multiple regression analysis revealed that the reduced well-being was due to social, life events and side effects. It is therefore recommended that these aspects should be described when patients commence a course of medicinal treatment i.e. the social life events and side effects of the medicine in connection with the actual subjective dimension of quality of life.