Background: This study was performed to determine the effect of aging of different types of composite material restorations on: Shear bond strength (SBS) to light cure and no mix chemical cure orthodontic adhesives with sapphire bracket and the debonding failure sites. Materials and methods: One hundred forty four composite disks were made from three different composite resin materials which are: 3M Filtek Z250, 3M filtek Z350 and 3M Valux plus, each group with (48) disks each, then according to the duration of storage each group was subdivided into two equal groups one of them stored for one day and the other was stored for one month, then each group was further subdivided into two equal subgroups with (12) disks each one bonded with light cure orthodontic adhesive and the other with no mix chemical cure adhesive. The sample was tested for bond strength using the universal testing machine and the Adhesive Remnant Index (ARI) was inspected under the stereomicroscope. Results: The results revealed that there was a highly significant difference among the three types of composite materials bonded with light cure orthodontic adhesive as showed by ANOVA test, while the T test showed that there was no significant difference between the two storage durations and also between the two orthodontic adhesives for both Filtek Z250 and Valux plus. Conclusions: The highest (SBS) values were obtained from Filtek Z350 samples than other two types of composite. All the samples stored for one day showed higher values of (SBS) than those stored for one month.
The poor hole cleaning efficiency could causes many problems such as high torque, drag, poor hydraulics and pipe stuck. These inherent problems result in an avoidable high operation cost which this study tried to address. In this study, the effect of cutting density on hole cleaning efficiency in deviated and horizontal wells was investigated. Experiments were conducted using 40 feet (12 m) long of flow loop made from iron and PVC. However, the test section was made from PVC with (5.1m) long and (4” ID) for outer pipe and (2” OD) inner pipe. The cutting transport ratio (CTR) was determined from weight measurements for each test. Cutting Transport Ratio has been investigated for effects of the following parameters; flow rate, cu
... Show MoreThe need for Dewatering is very important in construction workshops field and sometimes it needs to pay more attention as a result of its impacts on causing additional settlement of nearby pile foundations. Dewatering construction may become a costly topic if ignored during project planning and designing .In this paper a simplified procedure maybe adopted to calculate the foundation settlement induced by using dewatering system which is required to lower the water table level to reach a dry condition during construction. Synthesized case study adopted at a specified location in Baghdad city and analysis are computed for two types of piles both of them are submerged with water. Results shows the effect of dewatering on pile foundatio
... Show MoreThe blade pitch angle (BPA) in wind turbine (WT) is controlled to maximize output power generation above the rated wind speed (WS). In this paper, four types of controllers are suggested and compared for BPA controller in WT: PID controller (PIDC), type-1 fuzzy logic controller (T1-FLC), type-2 fuzzy logic controller (T2-FLC), and hybrid fuzzy-PID controller (FPIDC). The Mamdani and Sugeno fuzzy inference systems (FIS) have been compared to find the best inference system used in FLC. Genetic algorithm (GA) and Particle swarm optimization algorithm (PSO) are used to find the optimal tuning of the PID parameter. The results of500-kw horizontal-axis wind turbine show that PIDC based on PSO can reduced 2.81% in summation error of power
... Show MoreBackground & objective: Difficult intubation remains a risk for patients undergoing general anesthesia (GA) or mechanical ventilation in an intensive care unit (ICU). Macroglossia is a known factor for difficult intubation. But it is not routine to assess the tongue size to predict difficult intubation. Studies are found deficient in comparing usefulness of measuring thyromental distance and the tongue thickness (TT) measured by ultrasonography to estimate difficult intubation. We compared tongue thickness measured by ultrasonography and thyromental distance as a means to anticipate difficult intubation. Methodology: A convenient sample of 60 patients; 32 males and 28 females, who were undergoing elective surgery with GA were i
... Show MoreThe contractual imbalance is perceived today by the majority of the doctrine as being one of the pitfalls to the execution of the contracts. As a result, most legislations grant judges the power to intervene to restore it. Granting the judge the power to complete the contract raises the question of the extent to which the judge can obtain such power. Is it an absolute authority that is not limited? If so, is it a broad discretion in which the judge operates in his conscience, or is it a power of limited scope by specific legal texts and conventions? This is what we will try to answer in this research.
Wireless sensor networks (WSNs) represent one of the key technologies in internet of things (IoTs) networks. Since WSNs have finite energy sources, there is ongoing research work to develop new strategies for minimizing power consumption or enhancing traditional techniques. In this paper, a novel Gaussian mixture models (GMMs) algorithm is proposed for mobile wireless sensor networks (MWSNs) for energy saving. Performance evaluation of the clustering process with the GMM algorithm shows a remarkable energy saving in the network of up to 92%. In addition, a comparison with another clustering strategy that uses the K-means algorithm has been made, and the developed method has outperformed K-means with superior performance, saving ener
... Show MoreThe present research was conducted to investigate the effectiveness of a training program to improve some aspects of sensory integration disorder and its effect on self-direction among a sample of children with intellectual disabilities. The study sample consists of (10 subjects as an experimental group) were exposed to the training program، and the control group consists of (10 subjects as a control group) were not exposed to the training program. The study included the following tools: A scale of self-direction for intellectual disability (prepared by the researcher). Training program (prepared by the researcher). The Results of the study showed the following: There are no statistically significant differences between the means ranks
... Show MoreThis study aimed to determine the effect of varicocelectomy on sperm parameters, oxidant- antioxidant status and chromatin maturity percent. The current study has been conducted on 154 infertile patients complaining from varicocele and varicocelomized men in addition to 25 fertile men as control. The results revealed significant decrease (P<0.05) in sperm concentration, progressive motile sperm percent, normal sperm morphology percent, GSH, SOD1, CAT levels and chromatin maturity percent and significant increase (P<0.05) in MDA and ROS concentrations in infertile patients with varicocele when compared to fertile men. The results revealed improvement (P<0.05) of sperm parameters quality, GSH, SOD1, CAT, MDA, ROS concentration and chromatin m
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