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Abstract: The use of online courses on college campuses has grown substantially in recent years, despite limited information on how these courses are perceived by faculty and students, compared to traditional (classroom) classes. In this study, two separate, but equivalent, surveys were developed to compare the perceptions of faculty and students. Comparisons were made between the perceptions of faculty who have taught the same course using online and traditional formats to the perceptions of students who have taken online and traditional courses using a series of 7-point Likert scales. Both surveys measured: 1) perceptions of online versus traditional courses, 2) perceptions of students who take online courses and students' motivations for taking online courses, 3) perceptions of faculty members who teach online courses; and 4) demographic characteristics. Analysis of data included the comparison of mean values between faculty and students and Pearson correlation analysis to determine relationships between questions. Of the 25 questions investigated in this study, 12 showed significant differences in means between faulty and student perceptions (p<0.001). Significant findings from this research showed that compared to faculty perceptions, students tend to see online courses as more self-directed and believe that online students must be more willing to teach themselves. Students in online courses feel more disconnected from professors and fellow students than professors believe them to be. In addition, faculty tend to see the role of the professor as more critical to the success of online courses than students do. [Copyright &y& Elsevier]

Abstract: Zebrafish (Danio rerio) are model organisms for testing developmental toxicity at the morphological level. In this study, influence of temperature (24.5–28.5°C) and silver nanoparticles on developmental staging, ear–eye distance, and ratio of ear–eye distance to inner ear diameter was investigated. As temperature decreased, all endpoints showed developmental delay, with differences between endpoints in amount and type of delay measured. Differences in developmental delay patterns were observed, with rate delays increasing over time when staging endpoints were utilized and rates remaining constant when using ear–eye measurements. Integrated predictive equations were created to normalize each endpoint for temperature. Influence of image rotation on ear–eye distance accuracy showed that more than 75% eye overlap during analysis is necessary to minimize error. Exposure to silver nanoparticles demonstrated a lack of consistency between developmental endpoints and highlighted the usefulness of a multi-endpoint approach when measuring changes to developmental timing. [Copyright &y& Elsevier]

Abstract: Many laboratory studies have documented that mercury can be toxic to fish, but it is largely unknown if mercury is toxic to fish in their natural environments. The objective of our study was to investigate the toxic effects of mercury on northern pike (Esox lucius) at Isle Royale, Michigan. In 124 northern pike from eight inland lakes, concentrations of total mercury in skin-on fillets ranged from 0.069 to 0.622 μg/g wet mass (wet wt). Concentrations of total mercury in livers increased exponentially compared with concentrations in fillets, to a maximum of 3.1 μg/g wet wt. Methylmercury constituted a majority of the mercury in livers with total mercury concentrations <0.5 μg/g wet wt, but declined to 28–51% of the mercury in livers with total mercury concentrations >0.5 μg/g wet wt. Liver color (absorbance at 400 nm) varied among northern pike and was positively related to liver total mercury concentration. The pigment causing variation in liver color was identified as lipofuscin, which results from lipid peroxidation of membranous organelles. An analysis of covariance revealed lipofuscin accumulation was primarily associated with mercury exposure, and this association obscured any normal accumulation from aging. We also documented decreased lipid reserves in livers and poor condition factors of northern pike with high liver total mercury concentrations. Our results suggest (i) northern pike at Isle Royale are experiencing toxicity at concentrations of total mercury common for northern pike and other piscivorous fish elsewhere in North America and (ii) liver color may be useful for indicating mercury exposure and effects in northern pike at Isle Royale and possibly other aquatic ecosystems and other fish species. [Copyright &y& Elsevier]