Enzymes are nature's catalysts, mediating chemical processes in living systems. The study of enzyme function and mechanism includes defining the maximum catalytic rate and affinity for substrate/s (among other factors), referred to as enzyme kinetics. Enzyme kinetics is a staple of biochemistry curricula and other disciplines, from molecular and…

This presentation highlights the challenges of establishing a consistent application of the two terms, "threats" and "hazards," in academic courses and professional training, designed for emergency, disaster, and humanitarian management programs offered by public and private higher education, government agencies, and…

The process of turning a doctoral student into an independent researcher is usually guided by a professor. In this work, the supervisor-supervisee relationship is represented by a scheme inspired by Michaelis-Menten kinetics, which has been used to determine the rate of enzyme-catalysed reactions. Here, the time evolution of the number of…

The basic SIR (susceptible-infectious-removed) model of epidemiology is presented in chemical kinetic terms with a simple two-reaction mechanism. The conditions for the development of epidemics, the course of a simple closed epidemic, and the bases of several mitigation strategies are described in terms of the underlying first- and second-order…

This paper presents MATLAB user interfaces for two multiphase kinetic models: the kinetic double-layer model of aerosol surface chemistry and gas--particle interactions (K2-SURF) and the kinetic multilayer model of aerosol surface and bulk chemistry (KM-SUB). Each interface has simple and user-friendly features that allow undergraduate and…

Kinetic energy is usually the entry point for the study of energy in physics and is often perceived as unproblematic. We present evidence, however, that some learners who seem to have accepted the concept, from elementary school students to college physics majors and in-service teachers, nevertheless do not consistently attribute kinetic energy to…

Purpose: Laryngeal high-speed videoendoscopy (LHSV) has been recognized as a highly valuable modality for the scientific investigations of vocal fold (VF) vibrations. In contrast to stroboscopic imaging, LHSV enables visualizing aperiodic VF vibrations. However, the technique is less well established in the clinical care of disordered voices,…

The modeling of rates of biochemical reactions--fluxes--in metabolic networks is widely used for both basic biological research and biotechnological applications. A number of different modeling methods have been developed to estimate and predict fluxes, including kinetic and constraint-based (Metabolic Flux Analysis and flux balance analysis)…

The Gaussian gun is an arrangement of magnets and ball bearings (pictured in Fig. 1) such that--when the leftmost ball is released--the rightmost ball is ejected at high speeds. The device has been described in several articles on energy education. The sudden appearance of kinetic energy offers a productive context for considering a range of…

A physical chemistry lab for undergraduate students described in this report is about applying kinetic models to analyze the spread of COVID-19 in the United States and obtain the reproduction numbers. The susceptible-infectious-recovery (SIR) model and the SIR-vaccinated (SIRV) model are explained to the students and are used to analyze the…

The reaction rate and rate law are chemical kinetics concepts that undergraduate students have difficulty understanding and applying in real life. A further challenge is the overall reaction rate of consecutive reactions. Herein we present a creative teaching practice using the analogy-based approach to exploit the similarities between the…

Kinematic models are often very useful. The back and forth throw of a ball between two ice skaters may help us appreciate the meson exchange theory of Yukawa. If the skaters throw the balls at each other, they move backward, which is equivalent to a repulsive force between them. On the other hand, if they snatch the ball from each other, the…

Most biochemical transformations involve more than one substrate. Bisubstrate enzymes catalyze multiple chemical reactions in living systems and include members of the transferase, oxidoreductase, and ligase enzyme classes. Working knowledge of bisubstrate enzyme kinetic models is thus of clear importance to the practicing biochemist. However,…

An application for visualizing the dynamic properties of an equimolar binary mixture of isotropic reactive particles is presented. By introducing a user selectable choice for the activation energy, the application is useful to demonstrate qualitatively that the reaction rate depends on the above choice and on temperature. The application is based…

Models that are used to predict and explain phenomena related to molecular vibration and rotation are ubiquitous in physical chemistry, and are of importance in many related fields. Yet, little work has been done to characterize student use and application of these models. We describe the results of a multi-year, multi-institutional qualitative…