Yuba College

Oil from seeds of Citrus sinensis and M. barteri were extracted by solvent extraction using n-hexane. The percentage yield of the oil from seeds of Citrus sinensis and M. barteri was ascertained as 36.21 % and 12.56 % respectively. Physicochemical properties of the seed oils of Citrus sinensis and M. barteri were determined using standard methods. The extracted oils were further examined for antimicrobial studies. Nonetheless, oil extracted from Citrus sinensis and M. barteri seeds exhibits notable antimicrobial activity against every tested organism, including fungi and bacteria. However, at a concentration of 200 mg/ml, the oil from Citrus sinensis seeds showed more remarkable and excellent antimicrobial activity against E. coli, S. typhi, and C. albicans than the oil from M. barteri seeds. Therefore, Utilization of these seeds for residential and industrial usage in cosmetics and pharmaceutical will reduce environmental wastes and enrich their commercial value. Additionally, they offer legitimate channels for the pharmaceutical and cosmetic industries to channel these underutilized bio-resources (seeds) into medicines, soaps, and creams.

Passing the introductory calculus sequence is critical to undergraduate students’ retention in STEM programs. This study examines the relations between three interrelated processes found to influence mathematics learning and achievement: spatial skills, spatial anxiety, and math anxiety. Additionally, it examines the role of gender on these relations and if and how they help explain precalculus achievement. Findings revealed that spatial skills, spatial anxiety, and gender were linked to math anxiety. Furthermore, spatial anxiety and math anxiety were related to strong final exam performance, but spatial skills and gender were not related to achievement. The presented evidence is in accordance with prior research and corroborates the existence of these relational patterns in a postsecondary academic context in addition to the laboratory context. These findings have broad implications for the development and implementation of efforts aimed at improving postsecondary mathematics outcomes, and subsequent persistence, retention, and representation in STEM programs.

ABSTRACT Many students, when they take an elementary differential equations course for the first time, bring with them misconceptions from numerical methods that they had learnt in their calculus courses, most notable of which concerns the mesh width in using a numerical method. It is important that we strive to dispel any of these misconceptions as well as to make students aware that there is often a trade-off between the complexity of a numerical method and its computational cost. In this note, we provide examples to do that.