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Recently, topical products advertising cannabinoid ingredients have gained popularity. Consumers are seeing an increase of commercial products containing ingredients from hemp oil to cannabidiol (CBD) due to health benefit claims. Cosmetic products containing cannabinoids are currently not regulated at the federal level. A laboratory experiment for undergraduate students in analytical and organic chemistry courses was developed utilizing high-performance liquid chromatography (HPLC) analysis to identify and quantify cannabinoid compounds present in commercially available topical products. Students used calibration curves of a cannabinoid standard to quantify cannabinoids present in the CBD products. By comparing relative retention times of the cannabinoids present in the standard, students were able to identify the cannabinoids present in their lotion sample. Responsibilities and assignments suit students ranging from introductory to advanced chemistry courses. Students are provided the opportunity to extract and experimentally calculate the amount of CBD and compare to the amounts advertised on product labels. Results showed that the average CBD amounts were higher than advertised for all lotions except CBDFx when analyzed using HPLC. This experiment can be modified to incorporate a variety of different topical water-based products including hair products, shampoo, and other cosmetics. Furthermore, an analysis of samples using gas chromatography mass spectrometry (GC-MS) was also developed to adapt to instrument availability.

With the advancements in broad-spectrum sunscreens and the recent bans on benzene-based sunscreens due to their environmental toxicity, there has been a push toward broad-spectrum sunscreens containing in organic active ingredients. In this study, a procedure was developed to analyze the particle size and size distribution of inorganic active ingredients, titanium dioxide (TiO2) and/or zinc oxide(ZnO), of sunscreens with sun protection factor (SPF) values ranging from 15 to 50 using dynamic light scattering (DLS). These inorganic components are often engineered as nanoparticles in order to reduce visibility on the skin and retain UV scattering. Research suggests that the use of smaller nanoparticles to increase the efficacy of the inorganic filters may also be toxic to humans if it becomes permeable to the skin. This methodology allowed undergraduate students to workhands-on with particle sizing and compare sunscreen samples to nanopowder and dispersion standards using the effect of the hydrodynamic diameter. Students found that, due to agglomeration, the particle sizes for the nanopowder standards could exceed the manufacture's labeled size when dispersed in solution, which they then compared with their sunscreen data. The results also showed that some sunscreens had two distinct layers at the end of sample preparation, which could be correlated to the matrix components within the sunscreens. This study is intended for undergraduate analytical students and can be altered using the potential variations and scanning electron microscopy (SEM) with electron dispersive spectroscopy (EDS) to create a more challenging upper-level lab and allow for instrumentation comparisons.

This paper seeks to explain why the subject media studies looks and sounds the way it does today through the production of a genealogy of the subject. The questions addressed are first, why was this subject introduced into the curriculum in the 1970s? Secondly, how has knowledge in the subject been defined and contested, how and why has it changed in the course of the subject's history? Thirdly, which knowledge attains the status of truth and becomes the accepted definition of what the subject is about? The theoretical perspective adopted in this study draws from both postmodernist critiques and sociologies of subject knowledge. It presents a critical sociology of knowledge that draws insights from both social historians of school subjects and the work of Michel Foucault. The study draws a distinction between knowledge as defined by formal educational authorities (articulated in syllabuses) and knowledge defined by those practising the subject (teachers and curriculum advisors).

A series of undergraduate laboratory experiments that utilize reversed-phase HPLC separation, inductively coupled plasma spectroscopy (ICP), and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) are described for the analysis of commercial sunscreens. The active ingredients of many sunscreen brands include zinc or titanium oxide in addition to organic acids. Students determine the zinc content using ICP, and the chemical composition as well as particle sizes using SEM-EDS. The organic UV absorbers octocrylene and oxybenzone are quantified using HPLC. With the incorporation of these interesting characterization techniques in second or fourth-year chemistry courses, and by having students analyze sunscreen samples that are medically relevant in terms of health effects, students engage in timely research and at the same time gain exposure to a variety of instruments in the analysis of a familiar household product.

An assignment incorporating posters into a second-year analytical chemistry lab is described. Students work in groups and are assigned one of the application-themed weekly laboratories as a topic. Course data acquired for these weekly laboratories are compiled into spreadsheets that the poster group then analyzes to present in an on-campus poster session. Visual design with the use of minimal text is emphasized, and statistical analysis and spreadsheet usage are incorporated. This assignment provides the majority of students in the course with their first poster experience. By making the students revisit a previous lab and reconsider the topic using course-wide data, a simple lab of the week becomes an in-depth project culminating in a poster presentation. Student satisfaction with this assignment has been high both in terms of group work experience and the resulting poster.

Despite consensus regarding the civic shortcomings of American citizens, no such scholarly consensus exists regarding the effectiveness of civic education addressing political apathy and ignorance. Accordingly, we report the results of a detailed study of students enrolled in introductory American politics courses on the campuses of two large research universities. The study provides pre- and postmeasures for a broad range of political attitudes and behaviors and includes additional long-term observations in survey waves fielded 6, 12, and 18 months after the conclusion of the class. Long-term observation provides leverage absent in many prior studies and enables us to compare the changes we observe during the semester to those that take place beyond the confines of the classroom and during important political events, such as the 2012 presidential election. Also embedded in the study is an experiment designed to assess whether students' enthusiasm for "new media" (e.g., blogs) can be harnessed in American politics courses to stimulate long-lasting political engagement. We find evidence that civic education matters for some, but not all, measures of political engagement. Moreover, we find evidence that what one does in the classroom also matters. For some dimensions of political engagement, this study finds evidence of lasting civic education effects and the experimental manipulation compellingly locates the source of some engagement variation in the classroom.

Fluency with poroelastic theory is prerequisite to advanced study of material and mass transport properties in a wide range of contexts. Often the greatest challenge in introducing students to the subject is to help them visualize the fluid flows and deformations that accompany phenomena such as creep and stress relaxation. We have developed a simple physical model of poroelastic materials that provides an effective classroom demonstration. Parameters of the model can be altered to mimic changes in material elastic modulus, hydraulic permeability and thickness in order to demonstrate the effects of these variables on the kinetics of creep and stress relaxation. Since the apparatus highlights phenomena governed by the diffusion equation, it can also be used as an aid for visualization of solute diffusion and conductive heat transfer processes. Feedback from students has been very positive, indicating that this demonstration apparatus enhances their ability to visualize poroelastic mechanics at an introductory stage of learning.

Describes the Nuffield project that served as a resource for science centers across England and as a vehicle for the European Collaborative for Science, Industry, and Technology Exhibitions. Discusses the network of contacts extending from the BBC and British Association to science centers worldwide following the inception of the project by the Committee on the Public Understanding of Science. (JJK)