Apurinic/apyrimidinic (AP or abasic) sites are deoxyribonucleic acid (DNA) lesions that result from the loss of a nucleobase by hydrolysis of the "N"-glycosyl bond. AP sites are the most frequent lesions in cells and are caused by environmental and cancer therapeutic genotoxins. Herein, the bicinchoninic colorimetric assay, typically…

Quantitative analysis in analytical chemistry is divided into semi-,relative, and absolute analysis. An example of each analysis is pH test paper, internal standard, and standard addition, respectively. However, their definition and differences have not yet been explained to students sufficiently in classes as well as textbooks. Polymerase chain…

"Ulysses" by James Joyce (1882-1941) has a surprising amount of 19th-century, classical physics. The physics community is familiar with the name James Joyce mainly through the word "quark" (onomatopoeic for the sound of a duck or seagull), which Murray Gell-Mann (1929-2019 -- Physics Nobel Prize 1969) sourced from Joyce's…

Determination of enzyme activity is crucial for discovery, research, and development in life sciences. The activity of enzymes is routinely determined using spectrophotometric assays that measure rates of substrate consumption or product formation. Though colorimetric-based detection systems are simple, rapid, and economical to perform, the…

We have developed new rotors that can be classified into three groups by changing the rotors used in simple motors into various types. Group I has a semicircular shape rather than a perfect circle or square shape, group II has a structure consisting of several closed circles on one plane, and group III has a three-dimensional shape. We wanted to…

The novelty of the COVID-19 disease has paved the way to numerous scientific studies that aim to further understand its biology, and to different strategies that disseminate this information to promote public awareness. One of the strategies that the academe can employ is the inclusion of COVID-19 as a topic in a basic biotechnology course. This…

The trajectory of a ball rolling across an inclined plane was recorded on video film to determine if it followed a parabolic path as others have suggested. The challenges in this case were (a) to determine the magnitude and direction of the friction force on the ball, (b) to determine the effect of the friction force on the trajectory and (c) to…

A comprehensive laboratory work that allows students to gain hands-on skills in energy-efficient mechanochemistry is described. Standard university curricula are paying very little attention to mechanochemistry, although skills in this discipline are highly demanded among chemistry graduates. In this study, a comprehensive description of…

While visual representations are generally thought to help students learn chemistry, they can pose conceptual challenges. Arrows are a common visual feature used prominently across various visuals, such as energy diagrams. Although energy diagrams are widely used, research on what challenges arise in the context of energy diagrams is limited. To…

Blue (B), yellow (Y), red (R), and green (G) color-changing dye was used in a general chemistry course for first-year undergraduate students with nonscience majors to highlight the redox reactions written as the gain and loss of hydrogen. The first experiment is a vibrant color variation using a synthetic dye of indigo carmine. The second…

At the undergraduate level, the composite motion of simple harmonic vibrations has always been the main content of physics as well as several other scientific disciplines. Many textbooks tell us clearly that when the frequency ratio [omega][subscript 1]/[omega][subscript 2] of two perpendicular vibrations is simple integer ratio n[subscript…

When authoring physics problems, professors may develop an intuition for how much information they need to provide such that the problem has a unique answer and is not over constrained. It is an open question as to whether using intuition leads to a sufficiently broad range of problems. In this paper we discuss a systematic way of authoring…

The purpose of this study was to investigate undergraduate students' conceptions of Earth scientists, using drawing as a tool, during introductory Earth science courses. We explored two research questions: 1) What student conceptions are evident in undergraduate students' drawings of Earth scientists? and 2) How do undergraduate students'…

Literature on student ideas about circuits largely focuses on misunderstandings and difficulties, with seminal papers framing student thinking as stable, difficult to change, and connected to incorrect ontological categorizations of current as a thing rather than a process. In this paper, we analyzed 417 student responses to a conceptual question…

Many students find introductory general chemistry courses difficult because they feel alienated by traditional approaches to teaching and learning. This can become particularly problematic in laboratory sessions where students simply follow processes and procedures that students can view as being mundane and lacking creativity. Contextualised…