Experience and side effects of COVID-19 vaccine uptake among university students: a cross-sectional survey study.

Introduction: Many people expressed concern over coronavirus vaccinations' reliability and side effects. This research aimed to assess university students' perceptions and experiences regarding the side effects of the COVID-19 vaccines in Bangladesh. Method: We conducted an online cross-sectional survey to collect responses from university students vaccinated with any vaccines administered in Bangladesh between November 2021 to April 2022. Bangladeshi university students over the age of 18 and having an internet connection was included in the study. A binary logistic regression analysis along with Pearson's Chi-square test were used to identify COVID-19 vaccine-related side effects predictors after receiving the first dose. Results: A total of 1,176 participants responded voluntarily to the online study, and most were vaccinated. More than half of the participants received the Sinopharm vaccine (56.5%), while others received Covishield (8.9%), Moderna (7.3%), and Pfizer (5.8%) vaccine. Around 32% of the participants reported side effects after receiving the first dose of the vaccine, including pain and edema (78.4%), body temperature (20.3%), and headache (14.5%), while a few experienced allergy, anxiety, and uneasy feelings. About 17% of the participants reported experiencing side effects after the second dose of the vaccine, including pain and edema (7.5%), body temperature (8.8%), and headache (7.3%). Most side effects were significantly associated with the Moderna vaccine (p < 0.001). Female students and those previously infected with COVID-19 were significantly associated with the side effects after taking the first dose of the vaccine. Conclusion: We found that side effects are mild and did not pose a significant challenge to Bangladesh's effort in managing and reducing the risk associated with the COVID-19 pandemic.

Synthesis, characterization and application of a novel polyazo dye as a universal acid-base indicator.

A novel organic polyazo dye is synthesized by the diazotization of aromatic aniline, followed by coupling it with sulfanilic acid and N,N-dimethylaniline. Characterization was done by 1H-NMR, 13C-NMR, and FTIR spectroscopy. Differential scanning calorimetry (DSC) reveals that phase transition for this molecule is exothermic. The optical band gap is estimated from the absorption cutoff point using UV-Visible spectroscopy. Thermal gravimetric analysis (TGA) addresses the thermal stability of the molecule and is found to be at ∼250 °C. The structure of the synthesized molecule is analogous to that of methyl orange and contains three azo groups. These three azo groups help accept more than two protons and provide two pK a values when diprotic acid or a mixture of acids is used in different titrations. Specifically, when a polybasic acid is in strong base titration, the pK a values were found to be 3.5 and 9.1. Moreover, for strong base and (strong + weak) acid mixture titration, the pK a values are found to be 9.2 and 3.3. Furthermore, the pK a values are found to be 8.6 and 2.8 for (strong and weak) base mixture and (strong and weak) acid mixture titration, respectively. Owing to its increased proton accepting capacity, it can be found in the two pH ranges of 2.1-3.8 for orange color and 8.2-9.8 for yellow color, thus indicating a unique property as a universal indicator for acid-base titration. The dissociation constant of this dye is found to be 3.4 × 10-6, determined in a mixed aqueous solution of 10 wt% ethanol, and a linear relationship between pK a and pH is observed in this solvent system.