Background: One common undesirable side effect of orthodontic treatment with fixed appliances is the development of incipient caries lesions around brackets, particularly in patients with poor oral hygiene. Different methods have been used to prevent demineralization; the recent effort to improve the resistance against the demineralization is by the application of lasers. Materials and method: Thirty human premolars extracted for orthodontic purposes were used to test the effect of two energy level of ER-YAG laser on enamel resistance to demineralization. The brackets were bonded on the teeth and all the labial surface excluding 2 mm area gingival to the brackets were painted with acid resistance varnish. Three groups were generated. The first group was the control group (A), with no treatment was performed. In group II (B)and groups III (C); teeth were irradiated by ER-YAG laser of 200, 60 mj energy respectively. All the teeth were individually subjected to acid challenge cycle for 30 days. After debonding longitudinal sections were taken and examined under stereomicroscope. The enamel demineralization evaluation was done by taking the average of three depths at the centre of the artificial lesion. Also the enamel surface was classified by an experienced investigator according to acid etch pattern. Comparisons of the average depth values of the groups were performed with ANOVA and LSD tests. The statistical significance level was set at p ≤ 0.05. Results: The results revealed that average lesion depth was significantly deeper at the control group than the laser groups, and its significantly deeper in group (B) 200 mj than in group (C) 60 mj, enamel surfaces showed deeper pits and craters than in control group. Conclusions: the decrease in artificial caries lesion depth associated with use of the two laser energy level support the ER-YAG laser as a tool to increase enamel resistance to demineralization and white spot lesion prevention. Key words: Demineralization, ER-YAG, laser.
This study aims to study some morphological and reproductional characteristics in eleven species of two genera belonging to the family of Asparagaceae, which are Bellevalia Lapeyrouse, 1808 and Ornithogalum Linnaeus, 1753 and the species are: Bellevalia chrisii Yildirim and Sahin, 2014; Bellevalia flexuosa Boissier, 1854; Bellevalia kurdistanica Feinbrun, 1940; Bellevalia longipes Post, 1895; Bellevalia macrobotrys Boissier, 1853; Bellevalia paradoxa Boissier, 1882; Bellevalia parva Wendelbo, 1973; Bellevalia saviczii Woronow, 1927; Ornithogalum brachystachys C. Koch, 1849; Ornithogalum neurostegium Boissier, 1882 and Ornithogalum pyrenaicum Linnaeus, 1753. These species were identified and compared with each other; the results showed th
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The aim of this research is to measure the effect of Adey- Shire model in the achievement and critical thinking of first intermediate female students in mathematics. The researcher adopted the experimental method with a post-test, the research of sample consists of (60) female students, divided into two groups with (30) students in the experimental group, that studied with Adey- Shire model, and (30) students in the control group who studied in the usual way. The two groups are equivalent in many variables. The researcher makes two tests of multiple choices, the first one is an achievement test consists (30) items and another test was for a critical thinking test with (25) items. The statistical analysis make to both tests is made with s
... Show MoreBackground: Acute lung injury (ALI) is among the most serious conditions characterized by an exacerbation of inflammatory response that can result from a persistent lung infection. Carvone is chiral monoterpenoid ketone present in the essential oils of dill, caraway, and spearmint. It shows antioxidant, anti-inflammatory, and antimicrobial effects among others. In this study, the lung anti-inflammatory and protective effects and potential mechanism of action of carvone were investigated in ALI induced by Lipopolysaccharide (LPS).
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This research aim at finding out the impact of using the strategy of shape V on the achievement of the students of the Department of Artistic Education in the subject of "Principles of scientific Research ". This strategy is one of the cognitive strategies used in this topic . To verify the aim of the research ,the two researchers have put the following null hypothesis:-There are no significant differences on the level of 0,05 among the average degrees of the students of the experimental group in their answers on the topics of the pre and post cognitive achievement tests of the subject of "principles of scientific Research " . The two researchers have adopted the experimental approach which consists of one group . the population of the r
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Diabetic kidney disease is an illness of the glomerulus that interferes with the glomerular filtration barrier (GFB), which is worked to enable kidney to selective purification of water and solutes in addition to limiting the movement of large macromolecules such as albumin. In the glomerular endothelium, mesangial cells, foot cells, and the brush border of the proximal tubules, ACE-2 is expressed and that the kidneys represent the highest-expressing region of this enzyme. Thus, the current study aimed to evaluate ACE-2 level in this case compared to healthy condition. The study Conducted with 120 male and female ranging in age (30-65) years old. Ninety patients with type 2 diabetes subdivided into three groups on the basis of A
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The researchers reached many conclusions, the most important of which was the distinction of practitioners of sports activity with high degrees in the trait (social). At the same time, it was low in the trait (aggression –restraint-desisting) and non-practitioners were distinguished by sports activity with high degrees in the trait (aggression –restraint-desisting). In contrast, the degree was low in the trait (social), and there were significant differences in favor of practitioners of the activity of the athlete, Through the conclusions, the researchers recommend the need for university students to practice sports activities because of their positive impact on their health in general and on the deve
... Show MoreGas sensors are essential for detecting noxious gases that have a detrimental effect on people's health and welfare. Carbon quantum dots (CQDs) are the fundamental component of gas detectors. CQDs and graphene (Gr) were prepared using the electrochemical method. The gas sensitivity of these materials was evaluated at different temperatures (150, 200, 250 °C) to assess their effectiveness. Subsequently, experiments were conducted at different temperatures to ascertain that the combination of CQDs and Gr, with various percentages of Gr and CQDs, exhibited superior gas sensitization properties compared to CQDs alone. This was evaluated based on criteria such as sensitivity, recovery time, and reaction time. Interestingly, the combination was
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The polymeric complexes were obtained from the reaction of polymeric Schiff base.N-crotonyl-2-hydroxyphenylazomethine (HL), with divalent metals Pt (II), Cr (II). The modes of bonding and overall geometry of the complexes were determine through spectroscopic methods and compared with that reported from analogous monomeric ligand. This study revealed square planer geometry around the metal center for [Pt(L)Cl] and distorted octahedral geometry for Cr complex [Cr(L)Cl(H2O)2].
In this research Bi2S3 thin films have been prepared on glass substrates using chemical spray pyrolysis method at substrate temperature (300oC) and molarity (0.015) mol. Structural and optical properties of the thin films above have been studied; XRD analysis demonstrated that the Bi2S3 films are polycrystalline with (031) orientation and with Orthorhombic structure. The optical properties were studied using the spectral of the absorbance and transmission of films in wavelength ranging (300-1100) nm. The study showed that the films have high transmission within the range of the visible spectrum. Also absorption coefficient, extinction coefficient and the optical energy gap (Eg) was calculated, found that the film have direct ener
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The study aimed to describe the anatomical, histological, and histochemical structure of the proventriculuc of adult male Eurasian marsh harrier, Circus aeruginosus (Linnaeus, 1766) (Accipitriformes, Accipitridae). Six birds were used for this study. The histological sections of proventriculus were stained with hematoxylin and eosin, periodic acid Schiff, and alcain blue. The proventriculus, representing the upper stomach, appeared as a conical structure with a thick wall connecting the caudal end of the thoracic esophagus to the gizzard. It had a light brown color. Microscopic examination revealed that the proventriculus wall consists of the outer tunica serosa, the tunica muscularis, tunica sub mucosa, and the inner tunica mucosa.
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