Clinical Competence of Undergraduate Dental Students in Pediatric Dentistry at a Saudi Dental School

Objective: To assess the clinical competence of undergraduate dental students in pediatric dentistry at Qassim University dental school. Material and Methods: A retrospective audit of students' clinical competency sheets of fourth and fifth-year students (n= 102) over two years was performed. Mean competency scores for each clinical procedure as well as overall scores of the students were compared according to their academic level and gender. Also, the percentage of competent students was compared according to the academic level. Chi-square and t-tests were used to analyze the data (p<0.05). Results: Compared to fifth-year students, fourth-year students were significantly more competent in pediatric dentistry (100% scored >50% overall compared to 86.9 % of fifth-year students). They had significantly higher mean overall scores (84.63 ± 9.15 compared to 67.68 ± 13.83) as well as individual scores in performing an examination, diagnosis, and treatment planning of a child patient, restorations, and stainless steel crowns than fifth-year students. In addition, females had significantly higher mean scores in the aforementioned procedures and in placing esthetic crowns (p<0.05). Conclusion: Fourth-year dental students at Qassim University were more competent clinically than fifth-year students in pediatric dentistry. Also, in most of the shared procedures, females were more competent than males. A deficiency in the competence of fifth-year students was noted in pulp therapy, stainless steel and esthetic crowns procedures, and these are currently being addressed

Inhibition of cyclophosphomide mutagenicity using Glycyrrihza glabra root extract

The aims of the studying is using methanolic - water extract of the Glycyrrihza glabra root for inhibition the mutagenicity of anticancer drug by cytogenetic assays in vivo in three interaction between the drug and extract. The result shows that the extract is bioantimutagenesis. The treatment by extract after drug causes increase mitotic index and decrease chromosome aberration and sperm head abnormalities. The thin layer chromatography of the extract show that is contains different polar compounds

Synthesis, Mesomorphic and Molar Conductivity Studies of some Macrocyclic Phthalocyanine Palladium (II)

Two series of Macrocyclic Phthalocyanine Palladium(II) namely 4,4,4,4-RnPcPd and 3,3,3,3-RnPcPd were prepared and characterized. The mesomorphic investigation by hot stage polarizing microscope for these series was carried out. This investigation revealed that the 4,4,4,4-RnPcPd series exhibited columner mesophases while the second series 3,3,3,3-RnPcPd did not show any liquid crystalline properties.The molar conductivity measurments carried out in dimethyl sulfoxide and N,N-dimethyl formamide solvents for all prepared compounds at room temperature indicate that these compounds behave as weak electrolytes . Keywords: Macrocyclic compounds, Macrocyclic complexes, Liquid Crystals, Conductivity

Cytotoxic and Genotoxic Effect of Aflatoxin B1

The aims of study is to determine cytogenetic and genotoxic effect of aflatoxin B1 in vivo, cytogenetic tests are used in studying include chromosome malformation, cell proliferation and plast index test in bone marrow cell in Wight albino rats, the results show that toxin causes Varity in chromosome malformation and increased the rate of it, so it increased in cell proliferation and plast index value compare with negative control

Effect of Cucumber mosaic virus (CMV) on the Content of Some Cucumber Genotypes of Nitrogen, Protein, Phenols, and Flavonoids

This study was carried out to secreen the response of ten cucumber genotypes (AH-38، HA-37،HA-2160 ،HA2114 ، HA-2122 ،HA-12 ،HA-16 ،HA-41 ،CU-O719 , and CU-2102) against Cucumber mosaic virus (CMV) and to know the effect of infection on some of the plant contents of nitrogen, protein, phenols, and flavonoids. This study was carried out in the laboratory of Plant Virology and plastic houses of the College of Agriculture, University of Kerbala. The results showed that all cucumber genotypes tested in this study are susceptibe to CMV with severity infection ranged from 15-100%. It was also proved that the viral infection had a clear effect on reducing the content of the plant of nitrogen and protein in the genotypes and the most affected genotype was HA-2122 that was a significantly different from the content of nitrogen and protein in the non-infected plants. CMV was also found to have an effect in increasing the plant content of phenols and flavonoids in all genotypes infected with the virus (CMV) and the most affected genotypes were HA-37 and HA-41 (2.51 and 2.42 mg g-1 dry weight, respectively) and significantly different from the content of the same non-infected genotypes that gave rates of 1.66, 1.78 and 1.71 mg g-1 dry weight, respectively

Implementation of Crumb Rubber Modified Binder for Qatar Local Roads Construction Projects

The continuous increase in the pile up of used vehicle tires in Qatar poses a challenge contributing to potential environmental pollution problems. The magnitude of this problem can be drastically reduced by processing and recycling these tire wastes into crumb rubber, obtained from grinding up whole scrap tires, and incorporating into conventional asphalt binder to produce Crumb Rubber Modified Binder (CRMB) for asphalt mixes used in pavement construction. Asphalt mixtures which incorporates crumb rubber have been used in different parts of the world, notably USA since the 1960s, ostensibly to solve the associated environmental problems, but with added advantages of improving the overall performance of the asphalt pavement in terms of rutting and crack resistance, increased flexibility and durability. In 2018, the Roads Project Department (RPD) in collaboration with the Quality and Safety Department (QSD) of the Public Works Authority (PWA) in Qatar, undertook a demonstration project which utilized CRMB in the wearing course, in lieu of Polymer Modified Binder (PMB) originally proposed. Preliminary results from this project showed an encouraging prospect for adopting Crumb Rubber Modified Binder technology on local road projects, and eventually on all other roads in Qatar. Consequently, it became imperative for a tentative specification to be quickly put together for use by suppliers and contractors to achieve this goal. The preliminary results of this demonstration project are promising and the ensuing crumb rubber and CRMB guidelines have been useful

Preparation and Characterization of Antimicrobial PVA/ZnO Nanocomposite for Biomaterial Applications

السيطرة على العدوى الميكروبية هي قضية بالغة الأهمية في المستشفيات. البوليمرات المضادة للميكروبات هي أنواع جديدة من المعقمات، والتي يمكن استخدامها كبدائل للمطهرات في بعض الأحيان. تم في هذا البحث تكوين متراكب نانوي من بوليمر بولي فنيل الكحول مع الجسيمات النانوية لأوكسيد الزنك بحجم (90 نانو متر) بطريقة ذوبان المنصهر. حبيبيات أوكسيد الزنك النانوية تم تعديل سطحها بواسطة مادة الداي مثيل سلفوكسايد (DMSO) وذلك للحصول تشتيت جيد ضمن المادة الأساس ومن ثم تقليل التكتل. والغرض من هذه الدراسة هو تحديد النشاط المضاد للميكروبات للمادة المركبة النانوية (بولي فنيل الكحول\اوكسيد الزنك) ضد بكتيريا غرام-موجب (Pseudomonas aeruginosa;Escherichia coli) وغرام-سالبة (Staphylococcus aureus;Staphylococcus epidermidis)    والفطريات Candida. تم دراسة تأثير تركيز وحجم الجسيمات على النشاط المضاد للبكتيريا لجسيمات أوكسيد الزنك النانوية باستخدام اختبار اقل تركيز يثبط البكتيريا (MIC) وتم دراسة النشاط المضاد للميكروبات للمادة المركبة بواسطة اختبار Agar well diffusion. وأظهرت النتائج أن النشاط المضاد للميكروبات من الجسيمات ZnO مع PVA يزداد مع انخفاض حجم الجسيمات وزيادة تركيز .ZnO.Control of microbial infections is a highly important issue in hospitals. Antimicrobial polymers are new kinds of antiseptics, which can be used as alternatives to disinfectants in sometimes. Zinc oxide nanoparticles (90 nm) with polyvinyl-alcohol (PVA) generated by melting route. ZnO NPs was modified by dimethyl sulfoxide (DMSO) to get on uniform distribution within the matrix and then reduce agglomeration. The purpose of this study is to determine the antimicrobial activity of PVA ̸ ZnO nanoparticles against Gram-negative bacteria (Pseudomonas aeruginosa; Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus; Staphylococcus epidermidis) and fungi (Candida albicans,). The effects of concentration and particle size on the antibacterial activity of ZnO nanoparticles was studied using minimum inhibitory concentration (MIC) test and the antimicrobial activity of PVA/ZnO nanocomposite was studied using agar well diffusion method. Results showed that the antimicrobial activity of ZnO nanoparticles with PVA increased with decreasing particle size and increasing concentration of ZnO NPs. Results showed that all microbes were fully inhibited at 3.7 μg / ml concentration for ZnO NPs, but activity against bacteria was not observed at 1.8 μm / ml