سمیه قاضی

The purpose of this research was to develop and validate a tool to measure the effectiveness of the teaching process of student teachers in the 4th internship course.Content analysis was used to design the tool.First, the existing rubrics and textbooks of internship 4 in Farhangian University were analyzed and the semantic codes that included the concept of teaching effectiveness in its various fields(design, implementation, evaluation) were selected.66 semantic codes were extracted and after obtaining experts' opinions and making corrections, 66 items were reduced to 56 items.In the pilot implementation, the intended tool was implemented among a sample of 42 student teachers and the questions that needed to be revised were modified and finally, in the next step, 384 student teachers completed the questionnaire.The content validity of the research was confirmed by ten expert professors and its construct validity was investigated by factor analysis. Based on exploratory factor analysis with Varimax rotation, 56 items were placed in 4 factors, and these four factors in total explain 61.574% of the variance of the total scores. the results of the first and second confirmatory factor analysis and Cronbach's alpha coefficients supported the 4-factor structure of 56 items and confirmed its validity and reliability.

Simultaneous development of technology is composed with environmental hazardous with heavy-metals and organic solvents and thus toxic catalysts/organic solvents must be replaced with biocatalysts and water. Urease is a hydrolase enzyme and urease-urea can be considered a safe source of toxic ammonia in synthesis of nifedipine. Nifedipine is an antihypertensive drug synthesized by four–component reaction of 2 mmol methyl acetoacetate, 2–nitro-benzaldehyde, and ammonia using catalysts and organic solvents. The object of this research is replacement of toxic ammonia with urease-urea and organic solvents with water and study of heavy-metals and organic-solvent inhibition of urease on the synthesis of nifedipine.
In this experimental work, by controlling of yield and time of nifedipine synthesis via reaction of methyl acetoacetate, 2–nitro-benzaldehyde, and urease/urea in water, optimum urease/urea concentration, temperature, and pH for maximum yield were determined. Then, the effect of heavy-metal/organic solvent inhibitors on the production of ammonia and urease-catalyzed synthesis of nifedipine have been investigated.
Based on the yield of nifedipine, the activity of urease for ammonia production depends on parameters such as urease/urea amount, temperature, pH, and kind or concentration of inhibitors. The results accorded urease specificity for maximum dissociation of urea in experiment with 10 mg/mL urease, pH=7, and 70 C° in water, while heavy-metal ion/organic solvent inhibitory of urease showed trends of Hg2>Ag>Cu2>Pb2>Cd2 and acetonitrile>chloroform>dichloromethane to reduce in ammonia concentration and nifedipine.
Urease-urea makes a biocompatible source of ammonia for synthesis of anti–hypertension drug of nifedipine, while inhibitors such as heavy metal cations especially Hg2, organic solvents, and sulfuric acid decrease the reaction rate. Biocompatibility, use of water and no organic solvent/catalyst, high yield and selectivity are advantages of this green method in comparison to previous reported methods.