Search

Hydroden reduction of TiCl4 and BC13 causes the CO2 laser-induced chemical vapor deposition of titanium diboride. The dendritic growth on alumina at high temperatures is caused by the heat diffusion limitation, and mass diffusion regulates the deposition on the mullites. The mass diffusion is accompanied by heat diffusion limitation, while the growth rate and morphology are affected by hydrogen concentration variation.

Background: Dutch patients with an implantable cardioverter defibrillator (ICD) are restricted from driving for two months after implantation or shocks. This requires significant lifestyle adjustments and is one of the primary concerns of ICD patients. Previous studies indicated that compliance with the driving restrictions is poor, but insight in socio-demographic, clinical and psychological factors associated with compliance is limited. Hence, this study aimed to explore compliance with the driving restrictions and associated factors in a large sample of Dutch ICD patients. Method: Dutch ICD patients ( N = 313) completed an elaborative set of questionnaires at time of implantation and at four months after implantation, assessing socio-demographic, psychological and driving-related characteristics. Clinical data were collected from the patients' medical records. Results: A substantial subgroup (28%) of the patient sample (median age 64 (interquartile range = 55-71), 81% male) reported to have been noncompliant with the driving restrictions. Univariate analysis indicated that noncompliant patients more often considered refusing the ICD due to the restrictions, compared to compliant patients (19% versus 10%, p = 0.02). Multivariate analysis showed that the feeling of understanding the reason behind the driving restrictions was associated with better compliance (odds ratio = 2.16, 95% confidence interval 1.02-4.56, p = 0.04). No other socio-demographic, clinical, psychological or driving-related factors were associated with compliance. Conclusion: A large number of ICD patients does not comply with the driving restrictions after implantation. This study emphasised the importance of the patient's feeling of understanding the reason behind the restrictions. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. OBJECTIVE: In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated. METHODS: Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18 years were retrospectively collected from patients undergoing chronic ventricular pacing (>1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics. RESULTS: From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n = 147), RV endocardium (RVendo, n = 113) or LV epicardium (LVepi, n = 37). LVFS was significantly affected by pacing site (p = 0.001), and not by maternal autoantibody status (p = 0.266). LVFS in LVepi (39 ± 5%) was significantly higher than in RVendo (33 ± 7%, p < 0.001) and RVepi (35 ± 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS < 28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS >= 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was >= 50% in 17/18 (94%) LVepi-paced patients. CONCLUSION: In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing. [ABSTRACT FROM AUTHOR]

A series of downhole magnetometric resistivity (DHMMR) and downhole electromagnetic (DHEM) surveys were conducted near Broken Hill, New South Wales, Australia, and at Zinkgruvan, Sweden, to determine how probe and receiver equipment choices affect the amount of noise visible in borehole MMR and EM data. Noise analyses performed on the data, using the standard deviation to gauge the relative noise levels between different probes and receiver systems, indicate that high noise levels in MMR data result primarily from the use of a three-component EM probe, which has a reduced effective area and hence a higher noise floor compared with a single-component EM probe. High noise, attributable to cultural sources such as nearby power lines, in either MMR or EM data can be reduced through the use of full-waveform, multipurpose receiver systems. These systems allow for the use of tapered stacking, which is a more effective method of eliminating coherent noise associated with power-line transients than the boxcar-stacking method used by traditional receiver systems. [ABSTRACT FROM AUTHOR]