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Metal organic framework (Zn-MOF)/polyvinyl alcohol (PVA) nanofibrous composite new material has been fabricated using electrospinning and is characterized by a variety of physicochemical analyses, including Fourier transmitting infrared spectroscopy, X-ray powder diffraction (XRD), scanning electron microscopy-energy dispersive spectroscopy, nitrogen adsorption surface, and thermo gravimetric-derivative of thermogravimetry. In this study, the effects of a systematic study including a fractional factorial design were studied for arsenic removal. The results showed that although conventional methods have a high level of arsenic removal, the fractional factor method results in a relatively high level of absorption of arsenic. This high level of arsenic removal allows the potential use of nano adsorbents in various environmental fields. The systematic study developed in this study can be used as a novel protocol to eradicate pollution from different areas, including water, air, and soil. KEYWORDS arsenic adsorption, fractional factorial design, systematic study, Zn-MOF/PVA nanofibrous composite, 1 | INTRODUCTION Inorganic materials with combination of functionalized polymers are very interesting way to achieve advanced properties in field of chemistry and material science. [1-7] Metal organic frameworks (MOFs) [...]

Background and Aims: Bioaerosols are airborne particles that contain bacteria, viruse, and fungi. Human show different reactions to bioaerosols. This study aimed to determine the density of bacterial particles cultivable in the inside and outside air of kindergardens in Birjand, Iran. Materials and Methods: This study was performed based on a descriptive-analytical and cross-sectional research approach. Birjand was divided into five regions based on their geographical location, and six kindergardens were randomly selected. The sampling was performed in the morning shift from all six selected kindergartens. Additionally, triptic soy agar was used as the culture medium, and the sampling was performed at a flow rate of 28.3 L/Min for 35 min at a distance of 0.8 to 1 M above the ground in the center of each class. The data were analyzed in SPSS software (version 16) through the Mann-Whitney and Kruskal-Wallis statistical tests. A p-value less than 0.05 was considered statistically significant. Results: According to the results, the highest mean bacterial and microbial load and suspended particles were obtained at 3.83±8.04 CFU/m3 and 196.13±382.54 CFU/m3 in February and March, respectively. There was no significant relationship among bacterial density, suspended particles, and temperature (P>0.05). However, a significant relationship was observed between the bacterial density and total suspended particles (P<0.05). There was also a significant relationship between the amount of suspended particles (PM1, PM2.5, PM10) and the environment inside and outside the kindergardens (P<0.05). Conclusion: It is possible to determine the concentration of bacterial contamination in terms of quantity, type of identified species, and the amount of airborne particles to prevent the adverse health effects. [ABSTRACT FROM AUTHOR]