Zirconia ceramic restoration (ZCR) has a higher fracture incidence rate than metal ceramic restoration. Different surface treatments were used to improve fracture performance of ZCR such as grit blasting (GB) by aluminium oxide powder. This type of surface treatment generate residual stresses on veneering ceramic causing crack initiation and ending with a fracture. In order to overcome the stress generated by GB, zirconia surface coating is used as a surface treatment to improve fracture resistance and to accommodate stresses along the ZCR layers. Fifty zirconia ceramic crowns were fabricated and divided according to the type of surface treatment into three groups; the first group is (ZG), involving 20 cores were coated with a mixture of partially-sintered zirconia powder (PZP) and glaze ceramic powder; the second group is (ZL), including of 20 cores were coated with PZP and liner ceramic paste. The third group is grit blasting (GB), preparing of 10 fully sintered cores at 1350 °C which then abraded by 50 µm aluminium oxide powder. The groups ZG and ZL were further subdivided into ZG26, ZG47, ZL26 and ZL47 based on two PZP sizes (47 and 26 µm). Each treated core was veneered with the veneering ceramic layer. Fracture resistance (FR) was measured by the universal testing machine. Finite element analysis (FEA) was used to simulate the stress distributions on the coated and non-coated zirconia crown models. The ZG47 group had higher FR (647.92 ± 97.33 N) and a significant difference (P < 0.00) compared to GB and other coated groups. The FEA exhibited lower and evenly distributed stresses of the zirconia glaze model than the zirconia liner and the non-coated models. The ZG47 coating considered as an alternative method to GB treatment which increases the FR which significantly improved the clinical performance of the ZCR.
The inhibitory action of four lactobacilli isolates Lactobacillus bulgaricus, L. acidophilus, L. plantarum and L. fermentum, isolated from four different samples; yoghurt, vinegar, saliva and vagina respectively, on Escherichia coli and Staphylococcus aureus adhesion to uroepithelial cells were investigated. Results showed that all Lactobacillus isolates or their supernatant were able to reduce the number of the uropathogens attached to uroepithelial cells. However, inhibition level of lactobacilli cells was higher than their supernatant. Nevertheless, the human indigenous lactobacilli (L. fermentum and L. plantarum) were more competitive than food lactobacilli (L. acidophilus and L. bulgaricus).
This thesis aims to study the effect of addition polymer materials on mechanical properties of self-compacting concrete, and also to assess the influence of petroleum products (kerosene and gas oil) on mechanical properties of polymer modified self-compacting concrete (PMSCC) after different exposure periods of (30 ,60 ,90 ,and 180 days).
Two type of curing are used; 28 days in water for SCC and 2 days in water followed 26 days in air for PMSCC.
The test results show that the PMSCC (15% P/C ratio) which is exposed to oil products recorded a lower deterioration in compressive strength's values than reference concrete. The percentages of reduction in compressive strength values of PMSCC (15% P/C ratio) was
... Show MoreThis paper discusses a comparative study to relate parametric and non-parametric mode decomposition algorithms for response-only data. Three popular mode decomposition algorithms are included in this study: the Eigensystem Realization Algorithm with the Natural Excitation Technique (NExT-ERA) for the parametric algorithm, as well as the Principal Component Analysis (PCA) and the Independent Component Analysis (ICA) for the non-parametric algorithms. A comprehensive parametric study is provided for (i) different response types, (ii) excitation types, (iii) system damping, and (iv) sensor spatial resolution to compare the mode shapes and modal coordinates of using a 10-DOF building model. The mode decomposition results are also compared using
... Show MoreThe design was distinguished in Late Twenty-First Century With new and new methods Through which the ability to adapt all technical media in the formation of two-dimensional and three-dimensional figures and shapes was achieved .
Which led to the emergence of endless sets of design ideas characterized by the heterogeneity of design forms and design solutions that preceded it. The designer could not access these creations in various architectural and artistic fields only through computer programs, especially those related to the activation of mathematical logic and what is known as algorithms in the formation and construction of the form, which led to the emergence of the "parametric direction" and the problem of research is summarized
Background: Bloody diarrhea plays a major role in
morbidity and mortality especially in developing
countries, it is usually a sign of invasive enteric
infection, there is a thought that amoebic dysentery is
more common than bacillary dysentery in Iraq, and
from 1989 to 1997 amoebic dysentery increase from
20000to 550000 patients.
Objectives: This study aims to:
1. Outline the incidence of various infectious causes of
bloody diarrhea in Erbil district.
2. Assess the effect of multiple factors like age, sex,
source of water supply, etc... On the incidence of
amebic and bacillary dysentery.
3. To provide baseline data for making strategic plan to
reduce the diarrhoeal mortality and morbidity.
Met
Persuasion is a process studied by many scholars from the Greek time until the present. One persuasion strategy is metadiscourse, which refers to the writers' awareness of their text, the way they present themselves to the readers. The writers use metadiscourse markers to help the readers understand the real meaning of the text (Hyland 2005). The paper carries out a qualitative and quantitative analysis of the employment of persuasive metadiscourse markers in two English trade agreements and two Arabic agreements has provided in terms of Hyland's (2005) model of interactive and interactional markers. The aim is to find out whether all types of metadiscourse markers are used or not, and also to see whether English or Arabic employs
... Show MoreDomesticated translation has been for a long time the norm in cultural communication between nations all over the world. The texts are translated mainly into English (being the dominant language) in terms dictated principally by the requirements of the target language (English). The claim has been that fluency, readability, and immediate intelligibility can be guaranteed as far as the reader of the target language is concerned (English). The foreignness of the text (of the culture which produced it) would be not preserved. Not only this. Being the language of predominant cultures, English has become number one among languages into which texts are translated. The imbalance has been noticeable between the volumes of works translated from a
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