The aim of this study is to compare the effects of three methods: problem-based learning (PBL), PBL with lecture method, and conventional teaching on the understanding of thermodynamics, group work and self-directed learning skills among physics undergraduates. The actual sample size comprises of 122 students, who were selected randomly from the Physics Department, College of Education in Iraq, for academic year 2011-2012. In this study, the pre and posttest were done and the instruments were administered to the students for data collection. Inferential statistics were employed to analyze data. The independent variables were the PBL, the PBL with lecture method, and the conventional teaching. Dependent variables of statistical analysis were posttest scores on the understanding of thermodynamics, group work skills, and self-directed learning skills. Covariates of statistical analysis were pretest scores of the understanding of thermodynamics, group work skills, and self-directed learning skills. The data were analyzed using statistical package social sciences (SPSS) version 19. Overall, the statistical results rejected all null hypotheses of this study. Thus, the use of PBL with lecture method enhances the understanding of thermodynamics better than using the PBL alone or using conventional teaching method. Using the PBL without or with lecture method promotes the skills of group work, and self-directed learning better than using the conventional teaching, among physics undergraduate.
The aim of this study is to provide an overview of various models to study drug diffusion for a sustained period into and within the human body. Emphasized the mathematical compartment models using fractional derivative (Caputo model) approach to investigate the change in sustained drug concentration in different compartments of the human body system through the oral route or the intravenous route. Law of mass action, first-order kinetics, and Fick's perfusion principle were used to develop mathematical compartment models representing sustained drug diffusion throughout the human body. To adequately predict the sustained drug diffusion into various compartments of the human body, consider fractional derivative (Caputo model) to investiga
... Show Morecurrent research aims to build an intellectual framework for concept of organizational forgetting, which is considered one of the most important topics in contemporary management thought, which is gain the consideration of most scholars and researchers in field of organizational behavior, which is to be a loss of intentional or unintentional knowledge of any organizational level. It turned out that just as organizations should learn and acquire knowledge, they must also forget, especially knowledge obsolete and worn out. And represented the research problem in the absence of Arab research dealing with organizational forgetting, and highlights the supporting infrastructure core, and show a close relationship with organizational le
... Show MoreBackground: The effect of garlic extracton fungal
growth and keratinolytic activity was studied in
Trichophytonmentagrophytes as one of the major
etiologic agents of human and animal dermatophytosis
in Baghdad and other parts of the World.
Objective: To investigated an alternative
antidermatophyte with minimum side effects which is
plant based and biodegradable natural product
Methods: Culture conditions for 30 isolates of T.
mentagrophytes isolated from human dermatophytosis
from both sexes with ages of 5-63 years in Central
Medical city for the period July 2009 to October 2009
were cultured on specific solid medium.
Results: The aqueous extract of garlic at various
concentrations inhibited the
Experimental and numerical investigations of the centrifugal pump performance at non-cavitating and cavitating flow conditions were carried out in the present study. Experiments were performed by applying a vacuum to a closed-loop system to investigate the effects of the net positive suction head available (NPSHa), flow rate, water temperature and pump speed on the centrifugal pump performance. Accordingly, many of the important parameters concerning cavitation phenomenon were calculated. Also, the noise which is accompanied by cavitation was measured. Numerical analysis was implemented for two phase flow (the water and its vapor) using a 2-D simulation by ANSYS FLUENT software to investigate the internal flow of centrifugal pump under c
... Show MoreThis takes research idea representations body in the works of artist Lisa Fattah al -Turk, and the qualities that represent them in the configuration and method of performance in order to achieve an important element in the development of the concepts of knowledge and cultural rights within the surface of the artwork including the body shape of his presence authority dominant in the history of art so it was for this audience motives Self , cultural , and part of the confirmation of the human side, and serves as a conveyor of ideas and diagnostic her.Search theme is determined to attend the address of the body in the works of artist Lisa Fattah al -Turk , a comparison in how the audience and what it will be , so Researcher seeks drilling
... Show MoreInvestment in Human is one of the best and most important investments as it is renewed and developed resource over time in comparison with depleted material resources. Human resources is considered the part of the population that could be employed economically to contribute in increasing production energies as it is the support pillar of the society and have great energies that construct the society and raise of nations as well as he is distinguished with characteristics of ambitions to freedom.
Iraq is one of the countries that has large number of population in age of work and production and reduce in age dependent classes (children and old people).This dynamic in population led to step
... Show MoreCadmium sulfide (CdS) nanocrystalline thin films have been prepared by chemical bath deposition (CBD) technique on commercial glass substrates at 70ºC temperature. Cadmium chloride (CdCl2) as a source of cadmium (Cd), thiourea (CS(NH2)2) as a source of sulfur and ammonia solution (NH4OH) were added to maintain the pH value of the solution at 10. The characterization of thin films was carried out through the structural and optical properties by X-ray diffraction (XRD) and UV-VIS spectroscopy. A UV-VIS optical spectroscopy study was carried out to determine the band gap of the nanocrystalline CdS thin film and it showed a blue shift with respect to the bulk value (from 3.9 - 2.4eV). In present w
... Show MoreBackground: This study aimed to apply a high-power pulsed alexandrite laser in vitro, the researchers tested different exposure periods, pulse lengths, and laser fluencies to see which dosage was most successful against S. aureus bacteria, which had developed resistance to many antibiotics. Method: Three bacteria samples were exposed to laser beams for 30 seconds with a 5ms pulse duration and a laser fluency of 5J/cm2. The process was repeated with laser fluencies of 10, 15, and 20. Results: The study was carried out by using different doses of Alexandrite laser. Results: There are significant differences (p = 0.05) in the mean number of bacteria colonies exposed for 30 and 60 seconds at any laser fluencies utilized in the present i
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