Background: To investigate the effect of different types of storage media on enamel surface microstructure of avulsed teeth by using atomic force microscope.Materials and methods : Twelve teeth blocks from freshly extracted premolars for orthodontic treatment were selected . The study samples were divided into three groups according to type of storage media :A-egg white , B- probiotic yogurt , and C-bovine milk . All the samples were examined for changes in surface roughness and surface granularity distribution using atomic force microscope, at two periods: baseline, and after 8 hours of immersing in the three types of storage media. Results: Milk group had showed a significant increase in the mean of the roughness values at the test period, while the egg white and the probiotic yogurt groups showed decrease in the surface roughness at the test period. No significant changes was found in the grain size of enamel surface of the avulsed tooth in any types of three storage media at eight hours interval. The use of egg white and probiotic yogurt to store the samples may be beneficial in that they contain various ions and proteins that fill up enamel valleys, while the longer periods of milk exposure encourage the bacteria to continue fermenting lactose, resulting in continual acid generation and increased demineralization. Conclusion : Milk group demonstrated the highest roughness values, while the egg white group demonstrated the lowest roughness values of the teeth. No significant changes in the grain size of enamel surface of the tested teeth in any types of three storage media at eight hours interval .
تم في هذه الدراسة ، تزيين رقائق أكسيد الجرافين (GO) بجسيمات كوبلتيت النيكل النانوية NiCo2O4(NC) عن طريق الترسيب في الموقع ، وتم استخدام المتراكب المحضر (NC: GO) كسطح ماز لإزالة صبغة الميثيل الخضراء ( MG) من المحاليل المائية. تم التحقق من التغطية الناجحة لأوكسيد الجرافين بجزيئات كوبلتيت النيكل النانوية (NC) باستخدام دراسات FT-IR وحيود الأشعة السينية (XRD). كانت أحجام الجسيم
... Show MoreZeolite Y nanoparticles were synthesized by sol - gel method. Dffirent samples using two silica sources were prepared.
Sodium metasilicate (Na2SiO3) (48% silica) and silicic acid silica (H2SiO3) (75% silica) were employed as silica
source and aluminum nitrate (Al(NO3)3.9H2O) was the aluminum source with tetrapropylammonium hydroxide
(TPAOH) as templating agent.
The synihesized-samples were characterized by X-ray diffraction, showed the requirement of diffirent aging time for
complete crystallization to be achieved. Transmission Electronic Microscope (TEM) images, showed the particles were
in the same range of 30 - 75 nm. FT-IR spectroscory, showed the synthesized samples having the zeolite Y crystal
properties. The i
Staphylococcal enterotoxin B (SEB) is a potent superantigen produced by
In this paper, an exact stiffness matrix and fixed-end load vector for nonprismatic beams having parabolic varying depth are derived. The principle of strain energy is used in the derivation of the stiffness matrix.
The effect of both shear deformation and the coupling between axial force and the bending moment are considered in the derivation of stiffness matrix. The fixed-end load vector for elements under uniformly distributed or concentrated loads is also derived. The correctness of the derived matrices is verified by numerical examples. It is found that the coupling effect between axial force and bending moment is significant for elements having axial end restraint. It was found that the decrease in bending moment was
in the
The study examines Julia Alvarez's role as a Dominican American author, poet, and essayist. Despite being born in New York City in 1950, she was raised in the Dominican Republic by a family with Dominican heritage. Her residence in her ancestral homeland significantly influenced her subsequent literary works. Upon her father's implication in a conspiracy against Dominican President, he departed from the Dominican Republic. Alvarez encountered the challenge of the English language. They were compelled to acquire proficiency in English due to the prevailing perception that anyone who spoke a language other than English were deemed "un-American" during that period. Alvarez recounted her initial encounters in the United States and the subseque
... Show MoreThe research deals with the lyrical introduction in the commentary of Tarfa bin al-Abd as a formative system characterized by flexibility and richness of imagination, which achieved a formative treatment and a unique construction within the structures of the structural and semantic language. I dealt with the poetic verses represented by the lyrical introduction as a formative hypothesis, basing its goal on a methodological framework distributed on the problem that was summarized by the following question: Is it possible to look at the poetic pattern within the pre-Islamic poem / hanging blinking as a model, in its plastic dimensions and to identify the stylistic treatment that achieves the formation space within the poetic text. The rese
... Show MoreThis study proposes a hybrid predictive maintenance framework that integrates the Kolmogorov-Arnold Network (KAN) with Short-Time Fourier Transform (STFT) for intelligent fault diagnosis in industrial rotating machinery. The method is designed to address challenges posed by non-linear and non-stationary vibration signals under varying operational conditions. Experimental validation using the FALEX multispecimen test bench demonstrated a high classification accuracy of 97.5%, outperforming traditional models such as SVM, Random Forest, and XGBoost. The approach maintained robust performance across dynamic load scenarios and noisy environments, with precision and recall exceeding 95%. Key contributions include a hardware-accelerated K
... Show MoreAvascular necrosis have always presented great challenges to orthopedic surgeons and patients, remain in many ways today the unsolved dilemma. Varieties of non-vascularized bone grafting techniques preceded by core decompression have been proposed with varying degrees of success. O bb j ee cc t i vv ee ss : The aim of this study is to review the the value of core decompression and non-vascularized tibial bone strip graft treatment for early stages of non-traumatic osteonecrosis stage II & III according to stein burg staging . M ee t hh oo dd ss : prospectively reviewed 26 patients (32 hips) with osteonecrosis of the femoral head between June 2006 and December 2013 at Imam Ali hospital in Sader city & Al-Wasity teaching hosp
... Show MoreThe research aims for the study about Ibn Tulun's personal and scientific biography to the
scholar, scientist and historian Ibn Tulun Shams Id- Din Mohammad Ibn Ali al-Dimashqi al-
Salihi (953 A.H. / 1546 A.D.) Ibn Tulun was a prominent Muslim historian in Blad al-
Sham.
At the first deals with Ibn Tulun's personal biography, author's name, Lineage, and
nickname, his nativity; his upbringing, and edification, his moral character, Finally, his death.
As to Ibn Tulun's scientific biography, at the first deals with his initiation into education
and learning , sheds light on his tutors and his authorities , scientific stations and travels , his
scholarly status , and Ibn Tulun's alumni or his students .