Knowledge and Attitude of Undergraduate Students and Interns toward Stem Cells and Their Implications in Dentistry: A Cross-sectional Study.

AIM: The primary ideology of this research was to evaluate both the knowledge and attitude of undergraduate students and interns regarding stem cells and their use in dentistry. MATERIALS AND METHODS: A cross-sectional observatory study was conducted among 310 dental students of Jazan University by making use of a self-explanatory questionnaire, containing a set of 25 questions and was sent as e-mail through Google e-forms. RESULTS: There was a good response rate of around 81.2%, of which 80.16% were aware of the fact that stem cells are unspecialized types of cells that come with the potential to turn into any cell type. Almost 65.08% of the participants considered the possibility to continue root formation post-trauma as the fundamental use of stem cells, and a majority (71.43%) of the participants showed great interest in garnering more knowledge and training in the area of stem cells. About 50% of the participants showed strong opposition to the concept of embryonic stem cells as these are basically fetched from an aborted fetus or from an embryo. There was a major section of the participants (79.76%) who were even keen on organizing more programs to create public awareness regarding stem cells. Mean knowledge and attitude scores among the participants were reported to be 7.57 ± 3.10 and 36.04 ± 6.51 respectively. CONCLUSION: Overall, the level of knowledge and attitude of dental students and interns at Jazan University towards stem cells and their implications in dentistry can be interpreted as adequate. CLINICAL SIGNIFICANCE: Advanced training and awareness campaigns on stem cells and dentistry would improve their knowledge and attitude.

Robust Spatial Modeling of Thermodynamic Parameters in a Full-Scale Reverse Osmosis Membrane Channel.

Full-scale reverse osmosis (RO) units usually consist of a set of pressure vessels holding up to six (1 m long) membrane modules in series. Since process parameters and water composition change substantially along the filtration channel in full-scale RO units, relevant thermodynamic parameters such as the ion activities and the osmotic coefficient change as well. Understanding these changes will lead to more accurate fouling prediction and to improvement in process and equipment designs. In this article, a rigorous thermodynamic model for RO concentrates in a full-scale module is developed and presented, which is capable of accounting for such changes. The change in concentrate composition due to permeation of water and ions is predicted locally in the membrane filtration channel. The local ionic composition is used to calculate the local activity coefficient and osmotic coefficient along the membrane channel through the Pitzer model for each modeled anion and cation. The approach developed was validated against related literature data, showing that Pitzer coefficient predictions were satisfactory. The spatial variation model was verified experimentally. It was found under the modeled conditions of high recovery that individual solute activity coefficients could be diminished up to 65%, in our case for sulfate, from their initial value from the membrane inlet to the outlet, and the water osmotic coefficient increased 3% as concentrate salinity increased from the membrane inlet to the outlet. Modeled at moderate recovery, the sulfate still achieved a statistically significant drop of 34% and an opposing trend of a decrease of 0.5% for the osmotic coefficient. These variations in internal water chemistry along the channel can significantly impact predicted recovery, fouling propensity, and permeate quality. Fouling prediction with our approach was also assessed through a theoretical fouling index to demonstrate the significance of ion activity over concentration-based calculations. Additionally, data from a pilot plant RO filtration channel was used to carry out a sensitivity analysis to show the capability of the developed model.