Background: Ceramic veneers represent the treatment of choice in minimally invasive esthetic dentistry; one of the critical factors in their long term success is marginal adaptation. The aim of the present study is to evaluate the marginal gap of ceramic veneers by using two different fabrication techniques and two different designs of preparation. Material and methods: A typodont maxillary central incisor used in the preparation from which metal dies were fabricated, which were in turn used to make forty stone dies. The dies divided into four experimental groups, each group had ten samples: A1: prepared with butt-joint incisal reduction and restored with IPS e.max CAD, A2: prepared with overlapped incisal reduction and restored with IPS e.max CAD. B1: prepared with butt-joint incisal reduction restored with IPS e.max press. B2: prepared with overlapped incisal reduction and restored with IPS e.max press. The marginal gap was measured with direct view technique using digital microscope at a magnification of 230x. Measurements were recorded for four surfaces for each sample and the maximum value was taken to represent that sample. Results: The data were analyzed with two-way ANOVA and independent samples t-tests. These tests revealed highly significant effects of both the preparation design and the technique of fabrication on the marginal gap (p=0.00), with CAD/CAM veneers, group A1 recorded the least marginal gap and pressing group, B2 showed the highest gap values. There was no significant effect of the interaction between the two parameters on the marginal gap. Conclusion: the CAD/CAM veneers with butt joint incisal reduction produced the most accurate margins while the least favorable combination was the pressable ceramic veneers with overlapped incisal reduction.
This paper describes a number of new interleaving strategies based on the golden section. The new interleavers are called golden relative prime interleavers, golden interleavers, and dithered golden interleavers. The latter two approaches involve sorting a real-valued vector derived from the golden section. Random and so-called “spread” interleavers are also considered. Turbo-code performance results are presented and compared for the various interleaving strategies. Of the interleavers considered, the dithered golden interleaver typically provides the best performance, especially for low code rates and large block sizes. The golden relative prime interleaver is shown to work surprisingly well for high puncture rates. These interleav
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Simple, sensitive and economical spectrophotometric methods have been developed for the determination of cefixime in pure form. This method is based on the reaction of cefixime as n-electron donor with chloranil to give highly colored complex in ethanol which is absorb maximally at 550 nm. Beer's law is obeyed in the concentration ranges 5-250 µg ml-1 with high apparent molar absorptivities of 1.52×103 L.mole-1. cm-1.
MB Mahmood, BN Dhannoon
The efficiency of attapulgite liners as anti-seepage for crude oil is examined. Consideration is given to the potential use of raw attapulgite and mixture attapulgite with prairie hay and coconut husk as liners to prevent crude oil seepage. Attapulgite clay used in this study was brought from Injana formation /Western Desert of Iraq. Two types of Crude oil brought from Iraqi oil fields were used in experiments; heavy crude oil from East-Baghdad oil field and light crude oil from Nassiriya oil field. Initially the basic properties of attapulgite and crude oils were determined. The attapulgite clay was subjected to mineralogical, chemical and scanning electron microscope analyses. Raw Attapulgite 150µm, 75µm, and 53µm were tested
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In this paper, we derive and prove the stability bounds of the momentum coefficient µ and the learning rate ? of the back propagation updating rule in Artificial Neural Networks .The theoretical upper bound of learning rate ? is derived and its practical approximation is obtained
Objective: The aim of the study is to assess the personal hygiene of adult patients with
diabetic foot.
Methodology: A descriptive study was carried out in Baghdad teaching hospital, Al-Karama teaching hospital
and Al-Kindey teaching hospital for the period of 10/1/2006 to 1/9/2006. A purposive "non probability" sample
of (100) patient.
Questionnaire was constructed for achieving the purpose of the study. Data were collected through the
application of the questionnaire and interview technique. Data were analyzed through descriptive statistical
approach (frequency & percentage) and inferential statistical approach (chi-square & correlation) by using of
SPSS.
Results: The study results indicated that the
David Hare (b.1947) is one of the most critically acclaimed, contemporary British dramatists. A playwright, director and filmmaker, he has written more than thirty plays for the stage and seven original screen plays for cinema and TV (Susan Emerling, p.1). He began his dramatic career in the late sixties. Along with such dramatists as Howard Brenton and Trevor Griffiths, he writes in the aftermath of the "Angry Young Men" tradition of John Osborne. It is a well-known fact that the element of anger continued in the drama of the 1960s and became even more radicalized after the social, cultural and political unrests of 1968 by the dramatists of the "second wave" to whom Hare belongs (John Russell Taylor, p.14). Setting his plays in a variet
... Show MoreSpider veins are a common aesthetic problem mainly in females , the conventional method of treatment is by microsclerotherapy (injections) but laser therapy has become increasingly efficacious and a convenient method for treatment. The present study was performed to investigate the effectiveness and safety of pulsed diode laser (810nm) by doing thermal photocoagulation. Ten patients with lower limbs spider veins were included in this prospective study. They were treated with a repetitive pulsed diode laser in non contact technique using the following laser parameters (wave length 810nm,power 1 W ,pulse duration 0.1 s., pulse interval 0.5 s, spot diameter 4mm ,power density 7.9 W/cm2). Laser therapy was performed on day zero and day fourt
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