Thirty one samples of gum swabs were collected from patients with tooth caries (5-30 years old) from the College of Science (Biology department )- University of Baghdad- Iraq for the period from October 2018 to December 2018. , The samples were transported, after inoculation in a transport media (nutrient broth), to the laboratory of the College of Science and then cultured on mannitol salt agar and blood agar). The isolates belonging to Staphylococcus spp. were identified by biochemical tests and Vitek 2 compact system, while the more antibiotic resistant isolates were identified by using Polymerase Chain Reaction(ï´¾PCR) and sequencing of 16SrRNA . The results showed sharp UV absorption peaks at 330 - 340nm and AFM at 56 nm. Transmission Electron Microscope (TEM) results showed that lemon silver nanoparticles (NPs) are spherical in shape. The results also demonstrated that the silver NPs have a higher antibacterial activity with a diameter of inhibition zone that reached 16mm as compared with the common three mouthwash and toothpaste brands (Colgate, Crest and Close up) that had inhibition zone values of 5-8mm.
ABSTRACT Background: Dental anomalies of teeth are major issue that contributes to dental problems encountered in general practice. The aim of this study is to measure the prevalence of dental anomalies and the associated etiological factors among 15 years old students in Basrah city –Iraq. Materials and methods: The total sample composed of 1000 students (435 males and 565 females) from urban area selected randomly from different high schools in the city. Diagnosis of dental anomalies were recorded by present or absent, diagnosis and recording of enamel defects were done according to the criteria of WHO (1997). Results: The prevalence of hypodontia was 4.6%, Females have higher prevalence than males (5.8% females and 3.0% males), ta
... Show MoreThis study discussed a biased estimator of the Negative Binomial Regression model known as (Liu Estimator), This estimate was used to reduce variance and overcome the problem Multicollinearity between explanatory variables, Some estimates were used such as Ridge Regression and Maximum Likelihood Estimators, This research aims at the theoretical comparisons between the new estimator (Liu Estimator) and the estimators
A series of heterogeneous basic catalysts of CaO, MgO and CaMgO2 at different calcination temperature were synthesized via solution combustion method. Different characterization techniques have been carried out to investigate the structure of the produced catalysts i.e. X-ray diffraction (XRD), particle size analyzer, morphology by atomic force microscope (AFM) and reflection using UV-VIS diffuse reflectance spectra. The particles size analyzer revealed that the mixed oxide catalysts calcined at different calcination temperature possess smaller nano size particles compared to pure CaO. Moreover, the energy band gap was calculated based on the results of diffuse reflectance spectra. The energy band gap was redu
... Show MoreIn the present study, nickel oxide nanoparticles (NiO NPs) were evaluated as an antibacterial and anticancer agent. The nanoparticles of nikel oxide were synthesized using aloe vera leaves extract and characterized with AFM (showing an average diameter of 45.11 nm), XRD and FE-SEM analyses. Three different concentrations (125, 250 and 500 µg/ml) were prepared from the synthesized NiO NPs and investigated for their potential antibacterial activity against both Enterococcus faecalis (Gram-positive bacteria) and Acinobacter baumannii (Gram-negative bacteria). While cytotoxicity and apoptotic activity were measured on both MCF-7 and AMJ13 cancer cell lines by MTT and caspase-9 luminescence assays. The results showe
... Show MoreLiquefied petroleum gas (LPG), Natural gas (NG) and hydrogen were all used to operate spark ignition internal combustion engine Ricardo E6. A comparison of CO emissions emitted from each case, with emissions emitted from engine fueled with gasoline as a fuel is conducted.
The study was accomplished when engine operated at HUCR for gasoline n(8:1), was compared with its operation at HUCR for each fuel. Compression ratio, equivalence ratio and spark timing were studied at constant speed 1500 rpm.
CO concentrations were little at lean ratios; it appeared to be effected a little with equivalence ratio in this side, at rich side its values became higher, and it appeared to be effected by equivalence ratio highly, the results s
... Show MoreBackground: Dental caries is a localized, progressive destructive, largely irreversible microbial based disease of multifactorial nature; these factors include (host, microbes and food) they influence differently on the initiation and progression of dental caries. The aims of the study: was to evaluate the effect of smoking on salivary flow rate, secretory immunoglobulin (SIgA) level and viable count of mutans streptococci (M.S) bacteria in oral cavity and their relation to dental caries experience. Material and method: The samples were collected from 80 male students ranging in ages from 18-22 years old. Where they divided in to two groups, 40 non-smokers (control group) and 40 smokers (study group). Unstimulated salivary samples were c
... Show MoreThe aim of this work is oriented to increase film cooling effectiveness value through numerical investigations for flow of Mach number not more than 0.3 around vane surface, to find the effects of inclination and compounds angles of round holes in staggered rows on adiabatic film cooling effectiveness of vane suction side. Multi cylindrical film cooling hole cases were studied with pitch ratio P/d =2 and 3, local blowing ratios M=0.382, 0.77 and 1.14, inclination angles a=30° and 45°, compound angles β= 0°, 15°, 30° and 45° and local momentum ratios I= 0.084, 0.34 and 0.756 for better cooling process.
A numerica
... Show MoreThis study was aimed to investigate the effects of Cuminum cyminum seed aqueous extract on the function and histological structure of rat kidney treated with dibutyl phthalate (DBP). Eighteen albino rats weighing 190-240g and aged 10-12 weeks were used for this study which went on for 28 days. The rats were divided into three groups (each with six animals): 1st group: control rats were given food and tap water, 2nd group was given DBP (420mg/Kg. B.W.) with tap water and diet, 3rd group were fed cumin plant orally at a daily dose of (200 mg/kg B.W.) and DBP (420mg/kg. B.W.) was given with drinking water and fed with diet daily. Kidney and liver function parameters were measured and hi
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