Application of Response Surface Method for Preparation, Optimization, and Characterization of Nicotinamide Loaded Solid Lipid Nanoparticles

Purpose: Solid lipid nanoparticles (SLNs) have been proven to possess pharmaceutical advantages. They have the ability to deliver hydrophilic drugs through lipid membranes of the body. However, the loading of such drugs into SLNs is challenging. Hydrophilic nicotinamide, a histone deacetylase inhibitor, is used to establish SLNs with enhanced encapsulation efficiency by using statistical design. Methods: The possible effective parameters of these particles’ characteristics were determined using pre-formulation studies and preliminary tests. Afterwards, the Response Surface Method (RSM) was utilized to optimize the preparation condition of SLNs. The effect of the amount of lipid, drug, surfactant, and the mixing apparatus were studied on particle size, zeta potential, and encapsulation efficiency of the obtained particles. The acquired particles were characterized in respect of their morphology, in vitro release profile, and cytotoxicity. Results: According to this study, all the dependant variables could be fitted into quadratic models. Particles of 107 nm with zeta potential of about -40.9 and encapsulation efficiency of about 36% were obtained under optimized preparation conditions; i.e. with stearic acid to phospholipon® 90G ratio of 7.5 and nicotinamide to sodium taurocholate ratio of 14.74 using probe sonication. The validation test confirmed the model’s suitability. The release profile demonstrated the controlled release profile following the initial burst release. Neither the nicotinamide nor the SLNs showed toxicity under the evaluated concentrations. Conclusion: The acquired results suggested the suitability of the model for designing the delivery system with a highly encapsulated water soluble drug for controlling its delivery

Sismik kaynak modeli paramatrelerinin olasılıksal sismik tehlike analizi sonuçları üzerindeki etkisi.

The inputs to the Probabilistic Seismic Hazard Analysis (PSHA) contain large uncertainties regarding the seismic source model parameters; therefore, the results may vary significantly due to subjective judgment and interpretation of the limited data. The objective of this study is to show the effect of seismic source model on the hazard results by quantifying the difference in the design ground motions for different risk levels at different locations around an active tectonic structure. Analysis showed that the variances in the hazard results obtained by different seismic source models are closely correlated with the location and hazard level. Additionally, sensitivity of the hazard results to the uncertainties involved in each source parameter, especially the source zone boundaries, annual slip rate, maximum and minimum magnitudes, fault width, b-value and scenario weights are analyzed and presented to provide insight on the relative contribution of source or fault parameters to the PSHA results. Finally, design ground motions for other spectral periods obtained by different seismic source models are compared with the Turkish Earthquake Code (TEC, 2007) requirements. The calculated uniform hazard spectrum (UHS) for almost all sites is lower than the TEC-2007 design spectrum, except for the near field sites. Results indicated that the difference between the spectra decreases as the distance between the site and source increases.M.S. - Master of Scienc

Effect of Seismic Source Model Parameters on the Probabilistic Seismic-Hazard Assessment Results: A Case Study for the North Anatolian Fault Zone

The inputs to the probabilistic seismic-hazard analysis (PSHA) contain large uncertainties regarding the seismic source model parameters; therefore, results may vary significantly due to subjective judgment and interpretation of the limited data. The objective of this study is to show the effect of seismic source models on the hazard results by quantifying the differences in the design ground motions for different hazard levels at different locations around the North Anatolian fault. Analysis showed the variances in the hazard results obtained by different seismic source models are closely correlated with the location of the site and hazard level. Additionally, sensitivity of the hazard results to the uncertainties involved in each source parameter, especially the source zone boundaries, annual slip rate, maximum and minimum magnitudes, fault width, b-value, and scenario weights are analyzed and presented to provide insight on the relative contribution of source or fault parameters to the PSHA results

Analysis of the attitude towards architecture major in two stages: major selection and after graduation

<p>ABSTRACT</p><p>In recent years, the desire for studying architectural engineering in Iran has been increased despite the decrease in the mathematics-physics volunteers. This article seeks to analyze the change in attitudes and perceptions towards selecting architecture as a major before and after graduation. To achieve the purpose of the research, qualitative research method and semi-structured interview tools with students in different levels, professional architects and university professors are used to collect data. The results of the study show that almost all the interviewers had chosen this major intentionally and not randomly based on their "interest". "Having both scientific-artistic dimensions", "growing in the artistic family context" and "gaining social prestige" have been the other main reasons for selecting this major. However, most graduates do not recommend selecting this major due to market downturn, lack of job opportunities, and low income. Meanwhile, the income issue was not generally considered when selecting the major. In this study, selecting architecture major for the second time was questioned in case of going back to the past, and a significant difference was observed between the students' group and the graduates. According to the results, while the majority of graduates, including postgraduate and doctoral students, professional architects and instructors, did not select architecture again due to the undesirable market and conditions for studying or working abroad, the majority of the student group will select architecture again. The results of this study indicate that students had selected architecture major by interest and with sufficient knowledge about the nature of the major, but still there is no accurate picture of the realities in professional market and for continuing education abroad. Therefore, it is necessary to provide more detailed knowledge for students interested in architecture with focus on income, professional market in the country and abroad and also chances for continuing education abroad.</p><p>Keywords: Architectural Engineering, Architecture Market, Field of Study, Major Selection.</p><p> </p&gt

BSHAP seismic source characterization models for the Western Balkan region

This manuscript presents the seismic source characterization models that were developed and used for the Western Balkan region in the framework of Harmonization of Seismic Hazard Maps in the Western Balkan Countries Project (BSHAP II) funded by NATO-Science for Peace and Security Program. Relevant knowledge about the geological and seismotectonic structure of Western Balkans and surrounding region was collected and utilized along with the BSHAP focal mechanism database and the BSHAP earthquake catalogue (Markusic et al. in Bull Earthq Eng 14(2): 321-343, 2016. doi: 10.1007/s10518015- 9833-z) to delineate seismic source models for different purposes. The super zone model of large zones bounds the regions with similar seismotectonic characteristics and catalogue completeness levels and was used for calculating the regional b-value of the magnitude recurrence relationship. Additionally, two models of smaller zones that represent the epistemic uncertainty in source geometry, maximum magnitude and style-of-faulting, were developed to be employed in the two-stage (circular and elliptical) smoothing procedure. Sets of sensitivity analyses are performed to support final estimates of some models' parameters affecting the smoothed seismicity rate. The seismic source models and the logic-tree presented here are to be implemented in the probabilistic seismic hazard assessment for the seismic hazard maps of the Western Balkan region