Solid dispersion (SD) formulation has attracted much attention due to its potential in enhancing dissolution performances of poorly soluble active pharmaceutical ingredients (API). Recently, a review on dissolution performances of SDs classifies the improvement into 3 categories, where 82 % of the studies showed improved bioavailability, 8 % showed reduced bioavailability and 10 % revealed similar bioavailability as compared to pure APIs. This indicates the inconsistent degrees of dissolution improvement of poorly soluble APIs in SD. Although a few factors related to the choice of carriers have been suggested to contribute to the dissolution improvement, however, the underlying factor determining the discrepancy in the degree of dissolution improvement remains in vague. It is hypothesized that the API contributes to the degree of dissolution improvement of SD. Hence, the factor of amorphous solubility advantage of API which leads to the different degrees of dissolution enhancement of SD is investigated in this research. Polyvinylpyrrolidone vinyl acetate (PVPVA)-based SD is prepared with three poorly soluble APIs. Physicochemical properties of SD were characterized using infrared spectroscopy, differential scanning calorimetry (DSC) and X-ray powder diffraction. The dissolution efficiency of each SD was calculated and compared to physical mixture and pure API. Theoretical amorphous solubility advantage for each API was calculated using the thermal properties obtained from DSC. The calculated values were found to be correlating well with the dissolution enhancement of the respective SDs. Hence, this theoretical approach can be utilized as an initial screening tool of API candidates in SD formulation during early pharmaceutical development.
The purpose of this research is to identify
the effect of the translation of poetic poem into an artistic picture in the achievement of retention among fifth grade students.
In order to verify the research goal, the first two hypotheses were determined. There are no statistically significant differences between the average scores of the experimental group who study (according to the technical picture) ) And the control group (according to the traditional method of art education) at the level of significance (0,05). The second is that there are no statistically significant differences between the average of the experimental group who study (according to the technical picture) and the control group who study (On According to the trad
A field study investigated the degree of need for managers working in the directories of education to develop their skills for the exercise of administrative empowerment, and it adopted the descriptive analytical approach. The research community, was determined which consisted of 126 principals, and the sample was selected with arte of randomly Statistics and by (100%) of the research community, as the number of respondents was (126) of managers working in the directories of education. A questionnaire was built which included 40 items distributed among the fields of study. Researchers verified its validity and reliability. The research data were analyzed using software (SPSS), the questionnaire was applied in the second semester of the a
... Show MoreThe development taking place on the sports field at the general level and in the game of football at the private level, being the most popular game in the world, has reached very advanced stages. The use of modern aids and technology has contributed greatly to this development from the collective and individual aspects, as the goalkeeper is the most important position in the team, the use of devices gave objective readings about the goalkeeper’s ability in terms of skill and physical aspects, as the importance of the research lies in designing an electronic device to measure the degree of bending of the knee angle because of its great importance in developing the skill of catching and dimensions of the high ball for football goalkeepers.
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Pollutants generation is strongly dependant on the firing temperature and reaction rates of the gaseous reactants in the gas turbine combustion chamber. An experimental study is conducted on a two-shaft T200D micro-gas turbine engine in order to evaluate the impact of injecting ethanol directly into the compressor inlet air on the exhaust emissions. The study is carried out in constant speed and constant load engine tests. Generally, the results showed that when ethanol was added in a concentration of 20% by volume of fuel flow; NOx emission was reduced by the half, while CO and UHC emissions were almost doubled with respect to their levels when burning conventional LPG fuel alone.
The study aimed to identify the degree of academic leaders practices at the University of Northern Border for creative leadership, which attribute to different variables (nature of work, employer, gender, years of experience in administrative work at the university). To achieve the goal of the study, the researcher used the descriptive approach survey. Therefore, the researcher used a questionnaire as a study tool, which consisted of (40) items that included dimensions (sensitivity to problems, initiative, originality, flexibility). The study sample consisted of (240) participants included (agents of colleges, and supporting deanships, and their employees) during the second semester of the academic year 1439/1440 AH. The results showed t
... Show MoreThis study was carried out to prepare and characterize domperidone nanoparticles to enhance solubility and the release rate. Domperidone is practically insoluble in water and has low and an erratic bioavailability range from 13%-17%. The domperidone nanoparticles were prepared by solvent/antisolvent precipitation method at different polymer:drug ratios of 1:1 and 2:1 using different polymers and grades of poly vinyl pyrolidone, hydroxy propyl methyl cellulose and sodium carboxymethyl cellulose as stabilizers. The effect of polymer type, ratio of polymer:drug, solvent:antisolvent ratio, stirring rate and stirring time on the particle size, were investigated and found to have a significant (p? 0.05) effect on particle size. The best formul
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In this work, an experimental investigation has been done for heat transfer by natural-convection through a horizontal concentric annulus with porous media effects. The porous structure in gap spacing consists of a glass balls and replaced by plastic (PVC) balls with different sizes. The outer surface of outer tube is isothermally cooled while the outer surface of inner tube is heated with constant heat flux condition. The inner tube is heated with different supplied electrical power levels. Four different radius ratios of annulus are used. The effects of porous media material, particles size and annulus radius ratio on heat dissipation in terms of average Nusselt number have been analyzed. |