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In an attempt to better understand the reproductive cycle of adult male loggerhead sea turtles, several techniques were used to assess their reproductive activity, including plastron-softness analysis, ultrasonography, laparoscopy, testicular biopsy samples, and measuring testosterone levels. Stress levels were evaluated on a subset of turtles by measuring testosterone and corticosterone concentrations after capture and before release. A total of 40 adult males were captured in the Port Canaveral shipping channel in April of 2006 and 2007. Four turtles were classified as reproductively inactive based on laparoscopic examination, histology of the testes, and testosterone levels. The relative area of plastron softness was significantly lower for the inactive males compared to the active males. Ultrasonography proved to be a promising tool, as we were able to visualize both the testes and epididymides on the turtles examined. Furthermore, we found no statistical difference in epididymal duct diameters measured by ultrasonography and during laparoscopy, suggesting that ultrasonography could be used successfully as a substitute for laparoscopic surgery. Finally, testosterone levels separated into 2 distinct groups, with concentrations of the inactive males below 5 ng ml -1 , and concentrations of the active males reaching 188 ng ml -1. We conclude that in order to reduce stress levels due to capture and handling, especially during laparoscopy, ultrasonography and plastron analysis could be used together as a way to determine the reproductive activity of adult males in the field. The results from this study also suggest that not all adult males participate in mating activity each year.

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Female African Americans comprise an underrepresented group in physics-focused careers. Between 2002 and 2012 African-American women comprised approximately 1% of graduating physics majors in the United States. It appears that at some point in their educational careers, many female African-American students stop considering the field of physics as being a viable or attractive option. One approach to garnering a greater understanding of this phenomenon is to specifically look into the impact of their self-belief; this encompasses students’ attitudes, self-concept, and self-efficacy. Self-concept refers to how one views one’s own strengths and weaknesses, while self-efficacy refers to one’s capacity to believe in one’s own abilities to succeed in specific situations. There does not yet exist a large body of research that specifically concentrates on middle and high school-aged female African Americans, low physics representation, and its connection to self-belief related to physics. In this instance, the question is: “Do these students believe they can succeed in physics?” This research investigates the levels of physics self-belief of female African Americans who are enrolled in middle and high school physics.

As students learn physics, they are often required to reason about the behavior of macroscopic and microscopic phenomena, and to synthesize prior knowledge from several different areas of physics to construct understanding of new ideas. This can be a tremendously difficult cognitive task for novice students, especially when the unfamiliar phenomena described are potentially microscopic or abstract. Therefore, it can be very helpful for physics instructors to develop and employ pedagogical techniques that help students to visualize and to reason productively about these concepts. A particularly effective strategy uses kinesthetic learning activities (KLAs).