Background: Relapse of previously moved teeth, is major clinical problem in orthodontics with respect to the goals of successful treatment. This study investigated the effect of orthodontic relapse on the proliferation of fibroblast and epithelial rests of Malassez cells in periodontal ligament of rat molars. Materials and Methods: Sixteen ten-week- old male Wister rats were randomly divided into four groups composed of four animals each: Group I received no orthodontic force (control). In both Group II and Group III, uniform standardized expansive springs were used for moving the maxillary first molars buccally for periods of one and three weeks respectively. The spring initially generated an average expansive force of 20 g on each side. In Group IV the springs were left for three weeks, until the maxillary first molars moved buccally, after that the springs were removed and the animals were scarified after three weeks of relapse tooth movement. After the humanly scarification of animals, each maxilla in all groups was dissected into two halves each half including the three maxillary molars and processed for histological examination. The number of both fibroblast and ERM cells in each cluster was counted in the PDL of the pressure side of the mesio-buccal roots of the maxillary right and left first molars in all groups and the surface areas of the ERM clusters were also measured in all groups. Results: The number of fibroblast was significantly increased at the end of active movement (Group III) and significantly very highly increased during the relapse period (Group IV). Regarding the ERM cells there were statistically significant increase in both the number of cells in each ERM cluster and the surface areas of the ERM clusters in Group III and highly significant increase in Group IV, while Group II showed no significant differences regarding all measurements. Conclusions: It was concluded that fibroblast and ERM cells may play an important role during orthodontic relapse
In this research, the effect of changing the flood level of Al-Shuwaija marsh was studied using the geographic information systems, specifically the QGIS program, and the STRM digital elevation model with a spatial analysis accuracy of 28 meters, was used to study the marsh. The hydraulic factors that characterize the marsh and affecting on the flooding such as the ranks of the water channels feeding the marsh and the degree of slope and flat areas in it are studied. The area of immersion water, the mean depth, and the accumulated water volume are calculated for each immersion level, thereby, this study finds the safe immersion level for this marsh was determined.
The dried fruit peel of pomegranate in Punicaceae family was fractionated chromatographically on Sephadex-LH-20 column .Gallic acid (trihydroxybenzoic acid) and its related galloyl esters such as gallotannin(i.e. β-penta-O-galloyl–D-glucose) were obtained homogenously. Different concentrations of gallic acid and gallotannin were used to determine their inhibitory effect on human serum cholinesterase. The enzyme activity was measured according to the method reported by the WHO .The inhibitory effect of these compounds on the activity of human serum cholinesterase have been studied in vitro .The inhibitory effect was remarkably clear with increasing concentration of gallic acid .Whereas galloyl ester showed n
... Show MoreThe interests toward developing accurate automatic face emotion recognition methodologies are growing vastly, and it is still one of an ever growing research field in the region of computer vision, artificial intelligent and automation. However, there is a challenge to build an automated system which equals human ability to recognize facial emotion because of the lack of an effective facial feature descriptor and the difficulty of choosing proper classification method. In this paper, a geometric based feature vector has been proposed. For the classification purpose, three different types of classification methods are tested: statistical, artificial neural network (NN) and Support Vector Machine (SVM). A modified K-Means clustering algorithm
... Show MoreThe study attempts to identify 1) the habits of playing video games among students, 2) the effect of playing video games on students’ academic achievement, 3) the statistically significant differences among students in regard of (gender, time of playing video games, number of hours). To this end, a five-likert scale questionnaire included four questions was applied to (250) male and female students chosen randomly from the second-intermediate stage at Al-Karakh side secondary schools. The findings revealed that students play games only on holidays and less than an hour daily, which means playing games does not affect their academic achievement. Additionally, the findings found there is a significant difference between male and female i
... Show MoreCadmium sulfide photodetector was fabricated. The CdS nano
powder has been prepared by a chemical method and deposited as a
thin film on both silicon and porous p- type silicon substrates by spin
coating technique. Structural, morphological, optical and electrical
properties of the prepared CdS nano powder are studied. The X-ray
analysis shows that the obtained powder is CdS with predominantly
hexagonal phase. The Hall measurements show that the nano powder
is n-type with carrier concentration of about (-5.4×1010) cm-3. The
response time of fabricated detector was measured by illuminating
the sample with visible radiation and its value was 5.25 msec. The
specific detectivity of the fabricated det
Background: Even the wide use of dental implants, still there is a proportion of implants are failed due to infection. Much considerable attention has been paid to modify the implant surface. Coating of dental implant with a biocomposite material of suitable properties can improve osseointegration. And this is the main concern of this study. The aim of present study was to evaluate the use of a biocomposite coating of dental implant with (ceramic nano Al2O3 and metalic AgNo3) on the bond strength at bone – implant interface and tissue reaction. Materials and methods: A total number of forty-eight screws, CpTi dental implant used in this study. Half of these screws were coated with a biocomposite material of nano (Al2O3and AgNo3), thi
... Show MoreThe research aims at showing the effectiveness of the existing deposit facilities in the liquidity of the Iraqi banking system for the period 2010/2017. The problem of research indicates that the Iraqi banking system enjoys high liquidity levels exceeding the standard rate set by the Central Bank of Iraq amounting to 30% For an appropriate level of liquidity remains a major challenge to the management of the bank because it is a trade-off between profitability and liquidity, and also indicates the existence of funds disabled and not available for credit and investment opportunities, and based on the research hypothesis:
The existence of a significant effect of the deposit facilities existing in the liquidity of the Iraqi banking
... Show MoreThis research aims to know the role of transformational leadership in the organizational success of the College of Education at Samarra University. The researcher adopted the analytical descriptive method in analyzing the research problem. The research included two main hypotheses that resulted in four hypotheses that were subjected to statistical tests. A sample of (54) The researcher used the survey method as a main tool for collecting data and information as well as visits and structured interviews that took place during the period of application. The research reached a set of conclusions and recommendations among the conclusions that there is an art relationship There is a strong and moral impact between transformational lead
... Show MoreCuInSe2 (CIS)thin films have been prepared by use vacuum thermal evaporation technique, of 750 nm thickness, with rate of deposition 1.8±0.1 nm/sec on glass substrate at room temperature and pressure (10-5) mbar. Heat treatment has been carried out in the range (400-600) K for all samples. The optical properties of the CIS thin films are been studied such as (absorption coefficient, refractive index, extinction coefficient, real and imaginary dielectric constant)by determined using Measurement absorption and transmission spectra. Results showed that through the optical constants we can made to control it is wide applications as an optoelectronic devices and photovoltaic applications.