Background: With the increase in composite material use in posterior teeth, the concerns about the polymerization shrinkage has increased with the concerns about the formation of marginal gaps in the oral cavity environment. New generation of adhesives called universal adhesive have been introduced to the market in order to reduce the technique sensitive bonding procedures to give the advantage of using the bonding system in any etching protocol without compromising the bonding strength. The aim of the study was to study marginal adaptation of two universal adhesives (Single bond™ Universal and Prime and Bond elect) using 3 etching techniques under thermal cycling aging. Materials and Methods: Forty-eight sound maxillary first premolar teeth were included in the study. Teeth were divided into two groups according to the universal adhesive used then each group was subdivided into 3 subgroups according to the etching protocol used. Standardized class I cavities were prepared in the teeth followed by the restoration of teeth using Filtek™ Bulk Fill Posterior Restorative composite material. After finishing and polishing, teeth were subjected to 500 thermal cycles in 55º-5ºC bath with dwell time of 30 seconds. Teeth then were examined using SEM to measure the marginal gap at 12 points. Data obtained were analyzed using one-way ANOVA and LSD test for each group and with student t-test to compare the two adhesives. Results: The result of this study the showed that etch and rinse technique showed significantly the least marginal gap width for both adhesive types. The selective etch technique showed lower gaps compared to the self-etch technique with no significant difference. The result showed that single bond universal showed significantly the least marginal gap for the all etching techniques compared to Prime and bond elect. Conclusion: The etch and rinse technique remains the most suitable technique for adhesive restoration. The type of adhesive plays an important role in adhesion.
The earth's surface comprises different kinds of land cover, water resources, and soil, which create environmental factors for varied animals, plants, and humans. Knowing the significant effects of land cover is crucial for long-term development, climate change modeling, and preserving ecosystems. In this research, the Google Earth Engine platform and freely available Landsat imagery were used to investigate the impact of the expansion and degradation in urbanized areas, watersheds, and vegetative cover on the land surface temperature in Baghdad from 2004 to 2021. Land cover indices such as the Normalized Difference Vegetation Index, Normalized Difference Water Index, and Normalized Difference Built-up Index (NDVI, NDWI, an
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preparation process of performance evaluation in organizations is of extreme importance, and under development in organizations and the opening of markets and technological developments in the industry and heightened competition among industrial organizations imposed systems are built for performance give a clear picture about performance and competition, And centered research problem in answering the following questions: Is performance evaluation system is available in Wasit State Company for Textile Industries(Research sample ), This research aims to assess the performance of policies and programs in the company, according to guide performance evaluation of programs and policies prepared by the Dutch Cou
... Show MoreThe UN organization is considered one of the most important organizations at the international level. It has accomplished multiple tasks and roles of many different issues and events that hit the developing and advanced world countries. It has performed a series of procedures and laws that have had an impact on ending the wars and conflicts that plagued some countries and continued for a period of time in the past. Moreover, it has improved the level of the international relations between a number of countries due to the problems and incidents took place between them. It has relied on finding solutions and treatments for humanitarian problems such as the preservation of the environment, preventing the spread of epidemics and diseases Thi
... Show MoreIron , Cobalt , and Nickel powders with different particle sizes were subjected to sieving and He-Ne laser system to determine the particle size . 1wt% from each powders was blended carefully with 99wt% from Iraqi oil . Microscopic examination were carried for all samples to reveal the particle size distribution . A Siemens type SRS sequential wavelength dispersive(WDS) X-ray spectrometer was used to analyze all samples , and the XRF intensity were determined experimentally and theoretically for all suspended samples , Good agreement between theoretical and experimental results were found .
Nowadays, the worldwide issue of the environment occupies the minds not only of ecological experts and politicians but also is addressed in cultural fields and literature in particular. The conceptualization of ecocriticism, whether in the ecological field or cultural studies, has come as a response to the increasing public awareness of numerous environmental crises. Most ecocritics regard John Clare (1793-1864) as a 'proto-ecological' British poet since his poetry incorporates ecological issues which were not then categorized as they are now. The study offers a precise illustration of ecocriticism coupled with a number of the most significant ecological concepts proven in selected poems by John Clare. The ecocritical reading of Clare's po
... Show MoreThe adequacy of diagnostic tests, together with trichomoniasis associated clinical symptoms, were investigated in females suffering vaginitis, and they were referred to the Gynecology Department, Al-Yarmouk Teaching Hospital during the period December 2004 – June 2005. The total number of patients was 250 cases (age range: 18 - 52 years), and each patient was examined using a sterile speculum to obtain vaginal swabs for examination. The diagnosis with T. vaginalis was done in many methods. The direct methods included wet and stained (Leishman's stain) examinations and cultivation in different culture media (Kupferberg Trichomonas Broth Base;, Trichomonas Agar Base; TAB and Trichomonas Modified CPLM), while the indirect methods were serol
... Show MoreThree hundred samples of washing water of vegetables were collected from women aged ( 15- 6o) years from different area in Baghdad governorate and its suburbs include two rural area ( Jaddria in Baghdad university and Al –Wagif in Rashdia) and two urbane area (Mansoure and Escan) . The samples were examined by precipitation method and then by staining method ( Lugols –Iodine stain) . The percentage of infection of intestinal parasites 36.3% include 15.3% for urban area and 57.3% in rural area and a significant difference was found between those groups . .The results showed also increased in the prevalence of parasitic infection in group age (15 -30) year .Also the results showed only 109 sample infected with eight specie
... Show MoreThe change in the optical band gap and optical activation energy have been investigated for pure Poly (vinyl alcohol)and Poly (vinyl alcohol) doped with Aluminum sulphate to proper films from their optical absorption spectra. The absorption spectra were measured in the wave range from (200-700) nm at temperature range (25-140) 0C. The optical band gap (Eg) for allowed direct transition decrease with increase the concentration of Aluminum sulphate. The optical activation energy for allowed direct transition band gap was evaluated using Urbach- edges method. It was found that ?E increases with increasing the concentration of Al2 (SO4)3 and decreases when temperature increases.
The centers of cities and historical quarter are exposed to a severe threat to the values of the physical and legal urban environment as a result of the value deterioration and the emergence, emergence and spread of new values on the intellectual and urban context, which generates the loss of the urban environment for its spatio-temporal continuity, flexibility, adaptation and continuity, and thus urban obsolescence, Hence the problem of the research in “the lack of comprehensiveness of studies on the phenomenon of urban obsolescence and its impact on the decline in the values of the quality of the built environment in historic
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