In recent years the possibility of observing by microscopy the dynamic activity of living cells has been largely pursued. We have developed a low-cost (~ 260 euros) on-stage cell incubator for inverted optical microscopes. This device allows to keep cells in good conditions for their survival and proliferation. The device is based on the use of…

A video of darkening scenery during the 15 min prior to totality of the 21 August 2017 total solar eclipse is presented and discussed. The luminances of the scenes at 1 min intervals are obtained by averaging pixel data of stills from the video. The experimental results are compared to the theoretical model of uniform radiance from the exposed…

This paper shows how a freely downloadable and powerful software package, "SMath Studio," can be used to model physical systems in physics teaching. The software can form the basis of lecture demonstrations by teachers or can be used individually by students working in an educational environment or on their own home computers.

The excessive "jargon" load in biology may be a hurdle for developing conceptual understanding as well as achieving core competencies such as scientific literacy and communication. Little work has been done to characterize student understanding of biology-specific jargon. To address this issue, we aimed to determine the types of biology…

This quasi-experimental mixed-methods design examined the effects of a Modified Argument-Driven Inquiry (MADI) on elementary school boys' and girls' engagement in learning science (ELS) and performance of argumentation. Thirty-two children were randomly selected to participate in a two-semester 24-h intervention, forming an experimental group (EG,…

A homologous pair of stereospecific NAD-dependent enzymes, (R)- and (S)-hydroxypropyl-coenzyme M dehydrogenase, are part of a bacterial pathway of short-chain alkene and epoxide metabolism. Their discovery and study, which spans multiple publications over more than a decade, is a data rich story that combines both classical and contemporary…

Microbiology as an academic discipline that does not have a long history, but the knowledge accumulated over the past three centuries is rather considerable, and courses in microbiology are commonly taught in colleges and universities throughout the world. In this article, many of the methods that can be used for teaching microbiology in a…

Many physics textbooks describe the way in which a capacitor in an RC circuit charges and discharges over time. A circuit that consists of a capacitor that is connected to a voltage divider as shown in Fig. 1 is commonly addressed, but the textbooks limit the discussion to the time immediately after the switch is closed and a long time after the…

The enzymatic determination of glucose in soft drinks, based on the glucose concentration measurement by means of the coupled reactions of glucose oxidase and peroxidase, has been implemented at the University of Malaga and optimized according to the Biochemistry and Chemistry undergraduate students' results and feedback throughout the last few…

Water can exhibit many different colors due to a variety of physical properties. Here, we focus on some observable colors within very pure freshwater. We only treat the absorption of light due to electronic and ro-vibrational excitations and scattering due to refractive index fluctuations of the water and the respective consequences for the…

A green laboratory experiment has been developed in which students perform an aqueous oxidation/cycloaddition reaction to convert salicyl alcohol into a pentacyclic diepoxydione that is readily isolated by filtration. Drawing on their knowledge of periodate-mediated 1,2-diol cleavage, students propose a mechanism for the oxidation of salicyl…

An undergraduate organic chemistry laboratory experiment involving the breakage of amide C-N bonds is reported. Whereas amides are typically considered stable species due to well-established resonance effects, this experiment allows students to cleave the amide C-N bond in a nickel-catalyzed esterification process. Moreover, students perform the…

The reduction of alkenes usually involves a hydrogen source and a catalyst. This process is both expensive and not well-suited for a large teaching laboratory. This paper presents an alternative procedure using a mixture of cobalt chloride and sodium borohydride to achieve the reduction of methyl oleate to methyl stearate. This procedure is safe,…

We herein report an efficient aerobic oxidative cleavage of meso-hydrobenzoin to benzaldehyde using a heterogeneous earth-abundant metal oxide catalyst. The reaction can be carried out at 70 °C in ethanol and uses a balloon filled with O2 as oxidant. Reagents are simple and have long shelf lives, and the whole laboratory exercise can be done in…

Students often find the study of electrostatics to be abstract, heavily mathematical, and non-intuitive. This paper describes an inquiry-based approach to teaching electrostatics in an introductory calculus-based physics class that emphasizes the primacy of student conceptual understanding.