A 3-year experience with guided tissue regeneration procedures

The Guided Tissue Regeneration (GTR) procedures are promoting a clinically and radiologically as well as histologically verifiably periodontal attachment gain. The objective of the study was to evaluate the clinical efficacy of these GTR techniques. In the past four years different barrier membranes (Gore-tex, Resolut and Guidor) were used around 318 teeth of 196 patients. 169 periodontal defects of 140 patients were followed up at least for two years. 54 patient had chronic adult type periodontitis, 67 suffered with rapidly progressing periodontitis and 15 had different severe mucogingival lesions. 111 vertical bony defects, 43 Class II-III furcation lesions and 15 mucogingival lesions were surgically corrected. The average preoperative probing depth (PD) and the clinical attachment loss (CAL) of the vertical bony defects were 5.3 +/- 1.7 mm and 6.2 +/- 1.9 mm respectively. The PD of the deepest Class III furcation lesion was 11 mm. The average gingival recession of the mucogingival lesions was 4.5 +/- 1.1 mm. The GTR technique provided the best results in the Class II-III furcation lesions, where an average 2.4 +/- 0.9 clinical attachment gain was observed one year postoperatively. The GTR techniques provided an average 1.8 +/- 1.2 mm attachment gain in the vertical bony crater cases. In both groups of cases a marked gingival recession followed the healing and the periodontal regeneration. In this way the average reduction in the probing depth exceeded the average attachment gain by more that 1.5 mm. 1 year after the operation the average radiologic bone fill was about 0.9-1.2 mm. The resorbable barrier membranes resulted in clinically significant root coverage and an average 3.5 +/- 1.7 mm gain in the width of keratinized gingiva. The success or failure of our cases were mainly determined by the patient's compliance, the level of the postoperative professional and individual oral hygiene and the number of periodontal recalls. These findings are also underlining the importance of the high standard of oral hygiene in the postoperative periodontal regeneration.     

An efficient design and implementation of Vedic multiplier in quantum-dot cellular automata

Telecommunication Systems - The Quantum-Dot Cellular Automata (QCA) is an incipient nanotechnology in contrast to the CMOS technology with appealing features like low power consumption, high speed...     

Sodar aspect sensitivity studies in the convective boundary layer

Measurements have been made of acoustic back-scattering intensity for the vertical and tilted sodar antennae in the convective atmosphere as a function of both zenith and azimuth. Variations in back-scattered intensity have been seen as observed earlier for nocturnal stable conditions. Small-scale anisotropic inhomogeneities in the turbulent thermal structure of the atmospheric boundary layer are considered to be reponsible for the observed anomalous behaviour in acoustic back-scattering.     

Effect of the opening aspect ratio on a buoyant pulsating exchange flow through a circular ceiling opening in a horizontal partition

An interesting transport phenomenon is observed through openings between two compartments separated by a thin, vented, horizontal partition such as those between containment areas in nuclear power systems, in other installations in the event of fire, passive cooling of heated structures, and in natural building ventilation. A heavier fluid located on the top of a lighter fluid and separated by a horizontal vent constitutes a gravitationally unstable system. Horizontal vents produce flow, which are unstable with irregular oscillatory behavior. The objective of the present work was to simulate such type of flow across a circular opening in a horizontal partition in the presence of a buoyancy force. Unsteady, axisymmetric Navier–Stokes equations were solved using the in‐house CFD code based upon the well‐established finite volume methodology. In terms of temporal differencing a second‐order accurate Crank–Nicolson scheme was used. Interpolation to cell faces for the convective terms was performed using a third‐order QUICK scheme and a second‐order central differencing was used for the viscous terms. Pressure‐velocity coupling was based on the SIMPLE procedure. The upper chamber was filled with salt water and the lower chamber with fresh water, creating a density differential between the two chambers. Opposing forces at the interface created a gravitationally unstable system, and an oscillating exchange of fluid developed. Several cases were numerically simulated and classified with respect to an aspect ratio L/D, where L represents the thickness of the partition and D represents the diameter of the opening in the partition. The flow coefficients and pulsation frequency have been determined. The effect of opening aspect ratio on frequency and flow coefficient was observed. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com /journal/htj). DOI 10.1002/htj.21023     

Unimodality and bimodality of mixed weibull distributions

The failure density function and probability density function of logarithmic lifetime are partially correlated. Normally, both patterns are either unimodal or else bimodal. This is not always the case. Quantitative criteria are introduced to check their correlation.     

Variability of sea surface salinity in the tropical Indian Ocean as inferred from Aquarius and in situ data sets

Sea surface salinity (SSS) is one of the key components of the Earth’s global water cycle. Reliable information on SSS is very important for ocean modelling, data assimilation, and ocean and climate research applications. In this study, SSS variability in the tropical Indian Ocean (TIO) was analysed using the Aquarius instrument on board the SAC-D satellite and in situ observations from the Research Moored Array for African–Asian–Australian Monsoon Analysis and Prediction (RAMA) buoys and Array for Real-Time Geostrophic Oceanography (ARGO) data sets for the period 2012–2013. Comparison of two recent versions (V2 and V3) of Aquarius-based SSS estimates to nine RAMA buoys on a daily timescale showed excellent mutual agreement. The systematic underestimation of SSS by satellite-based V2 products over the TIO shows a clear advantage for the new version product (V3). A larger root-mean-square error of the order of 0.50 psu in the satellite-based SSS was observed over the highly variable (larger standard deviation) Bay of Bengal region as compared with ARGO data sets. In the eastern equatorial Indian Ocean region, satellite-based SSS overestimated SSS below 34 psu and underestimated SSS of 34–35 psu as compared with ARGO data. However, the V3 SSS from Aquarius showed marginal improvement over V2 SSS. Monthly variation and fast Fourier analysis of the satellite-based SSS estimates are in reasonably good agreement with in situ observations which suggest that Aquarius is able to capture SSS variability in the TIO. The Aquarius-based V3 SSS showed a temporal autocorrelation of 0.6 over most parts of the TIO up to day 10, and decreased gradually with time. Overall analysis suggests that Aquarius-derived V3 SSS can detect variability in SSS satisfactorily in the TIO and is in reasonably good agreement with in situ observations.     

A simplified way of evaluating the radiation power integral

The total power from a radiating slot involves double integrals. A simple way of performing these integrations by using infinite product and series expansions within the Integrand is presented. A specific example is given to demonstrate its usefulness.     

The radiation resistance of a microstrip element

The radiation resistance of a rectangular microstrip element printed on a grounded dielectric is evaluated through the use of a bidimensional Fourier transform. The antenna is assumed to be half a guided wavelength long and to have a given width. The Q-factor of the antenna is assumed to be high so that the current in the feed at resonance is negligible. The longitudinal current distribution along the patch is assumed to resemble that of a resonant end-fed half-wavelength segment of a microstrip transmission line. The transversal current is taken to be constant. The resulting integrals are estimated in an asymptotic form using finite series and product expansions. An empirical formula replaces the former one for higher values of dielectric constants. The simple expressions thus derived lend insight into the nature of dependence of the radiation resistance on the various parameters such as width, thickness, and relative dielectric constant. In spite of their simplicity, the formulas provide quite accurate results