Background: Chief complaint of patients attending dental clinic represents the first step towards treatment plan. However, most of patients are not aware but the extent and severity of periodontal disease, which could be also, misdiagnose by the dentist. Aim of the study: To investigate whether reported chief complaint(s) are consistent with oral hygiene status Materials and methods: Records of 1102 patients, attending periodontics clinics in the college of dentistry/ university of Baghdad, were used to determine ten most commonly reported chief complaints. Sample of patients was further subdivided according to gender and age. In addition, plaque and gingival index were recorded to determine oral hygiene status. Results: Patients mostly attend clinic of periodontics in response to motivation by dental students or staff members or referred from other department. Further, removal of stain or deposits from their teeth represented the highest chief complaint (32%). Other true periodontal signs were seldom reported in spite of significantly high plaque and gingival index (P<0.05) with increasing age. Conclusion: Nation-wide educational programs are needed due to discrepancy between reported chief and periodontal health status. In addition, the actual need of patients, which was mainly oriented towards scaling, reflects ignorance and lack of knowledge about nature and alarming signs of disease.
This work included synthesis of several new polymers of polyacryloyl chloride in two steps . The first step the included the reaction of N-( sub. or un sub. benzoyl and sub. or un sub. acetyl ) amidyl sub. 2,6- diamino -4-methyl-1,3,5-triazine (1-5) by condensation of many substituted acid chlorides with 2,6- diamino -4-methyl-1,3,5-triazine . While the second step included the reaction of polyacryloyl chloride with the produced compounds (1-5) in step (1) in the presence amount triethyl amine (Et3N) to obtain new polyimides (6-10). The prepared compounds were characterized by UV. , FT-IR, and some of them by 1H-NMR and 13C- NMR spectroscopy.
The current study aims to produce cellulase enzyme from Streptomyces spp. isolates and study the effect of some cultural conditions on cellulase production; biofuel production from cellulotic waste through enzymatic and acids hydrolysis. Out of 74 isolates of Streptomyces sp. were screened for cellulse production in solid and liquid media. Results showed higher capability of isolate Streptomyces sp. B 167 for cellulase production and bioconversion of cellulose, therefore selected for further studies. The results of optimization revealed that the cellulase enzyme productivity by the selected isolate reached 2.1 and 2.28 U/ml after 48 h of incubation time and pH 7 respectively. Cellulase productions in tested isolate improved (2.57 U/ml) b
... Show MoreBiosorption of cadmium ions from simulated wastewater using rice husk was studied with initial concentration of 25 mg/l. Equilibrium isotherm was studied using Langmuir, Freundlich, BET and Timken models. The results show that the Freundlich isotherm is the best fit model to describe this process with high determination coefficient equals to 0.983. There was a good compliance between the experimental and theoretical results. Highest removal efficiency 97% was obtained at 2.5g of adsorbent, pH 6 and contact time 100 min.
Many studies have been published to address the growing issues in wireless communication systems. Space-Time Block Coding (STBC) is an effective and practical MIMO-OFDM application that can address such issues. It is a powerful tool for increasing wireless performance by coding data symbols and transmitting diversity using several antennas. The most significant challenge is to recover the transmitted signal through a time-varying multipath fading channel and obtain a precise channel estimation to recover the transmitted information symbols. This work considers different pilot patterns for channel estimation and equalization in MIMO-OFDM systems. The pilot patterns fall under two general types: comb and block types, with
... Show MoreA hybrid nanoparticles light emitting diode (NPs-LED) was fabricated as layers of ITO/TPD:PMMA/ Eu2O3 / Alq3 / Al, by phase segregation method using spin coating technique. The NPs-LED hybrid device emitted light and consisted of three layers in a definite order placed on the transparent conducting oxide as an ITO substrate; the first layer was made of (N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) benzidine) (TPD) and polymethyl methacrylate (PMMA) polymers combined together. The second layer consisted of Europium (III) oxide (Eu2O3), while the third layer was Alq3, one of the most frequently-used electron transport layers.
The electroluminescence (EL) of N
... Show MoreThe main purpose of this work is the construction of an optical parametric amplifier (OPA) to generate a 629 nm pulsed laser. KTP nonlinear crystals were used for both parametric oscillation and amplification. A singly resonant parametric oscillator (OPO) is constructed to generate a signal of 1.54 μm and idler of 3.4 μm when the OPO system is pumped by 1.064 μm Q – switched Nd: YAG laser. The signal was then mixed with the pumping beam in OPA system to form the wanted wavelength. The obtained optical conversion efficiency was 60%.
The presence of dyes in wastewater has become a major issue all over the world. The discharge of dyes in the environment is concerned for both toxicological and esthetical reasons. In this study, the removal of dyes from aqueous solution by electrocoagulation using aluminum electrodes as cathode and anode were investigated with the electrocoagulation cell of 1litter. The study included: the impact of various operating parameters on the dyes removal efficiency like pH, NaCl concentration, distance between electrodes, voltage, initial dyes concentration and type of electrodes. The dye (congo red) concentrations were (50, 100, 150, and 200 ppm), stirring speed was 120 rpm at room temperature. pH used was maintained constant
... Show MoreABSTRACT
Critical buckling temperature of angle-ply laminated plate is developed using a higher-order displacement field. This displacement field used by Mantari et al based on a constant ‘‘m’’, which is determined to give results closest to the three dimensions elasticity (3-D) theory. Equations of motion based on higher-order theory angle ply plates are derived through Hamilton, s principle, and solved using Navier-type solution to obtain critical buckling temperature for simply supported laminated plates. Changing (α2/ α1) ratios, number of layers, aspect ratios, E1/E2 ratios for thick and thin plates and their effect on thermal
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