In an ever-changing environment, survival depends on learning which stimuli represent threat, and also on updating such associations when circumstances shift. It has been claimed that humans can acquire physiological responses to threat-associated stimuli even when they are unaware of them, but the role of awareness in updating threat…

Water electrolysis, a well-known and simple experiment, confirms that a water molecule comprises hydrogen and oxygen atoms. In this experiment, hydroxide or hydrogen ions generated from each electrode were identified using an indicator based on the assumption that electrodes, electrolytes, and indicators do not participate in the water…

We have expanded Stein's "Sweetness of Aspartame" laboratory project (Stein, P. J. "J. Chem. Educ." 1997, 74, 1112, DOI: 10.1021/ed074p1112) to include extensive use of statistical testing. Students test the statistical significance of a nonzero intercept in a linear regression, bias in comparison to a true value, and…

Cell size is an important variable in the study of cellular growth, metabolism, and the cell cycle. The large size of "Amoeba proteus" and the ease with which it can be collected and cultured have made it a star in biology education--and it was a model for research on cell biology before the introduction of molecular genetic methods.…

A simple method is described for measuring liquid density based on stretching of the spring and equilibrium of weight and elastic force. The method involves placing a container with liquid under test on the spring causing a stretch of the spring that is directly proportional to the weight of the liquid. With this technique, the liquid density can…

A solar eclipse provides a well-characterized reduction in solar radiation. Solar radiation is a driving factor in meteorological and climate models. Hence, solar eclipses provide a unique opportunity to do large-scale meteorological experiments by measuring the effects on temperature, pressure, and wind while the atmospheric conditions stay…

The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of…

This study proposes a lab experiment consisting of three consecutive steps designed to expose undergraduate students to the fundamental aspects of nanoscience. Two different procedures for the reduction of silver ions were provided: Th was obtained. Next, the students explored the aggregation process of silver nanoparticles by converting one…

Studying the dynamics of beams is considered an indispensable field for mechanical and civil engineering students. This paper describes, in detail, the use of smartphones in educational practical works to determine and examine the dynamic characteristics of beams subjected to free vibration. Where the smartphone is equipped with a mobile…

Although it originates from the ancient Greeks, optics still arouses a lot of scientific interest, mainly due to the technological innovation associated with it. One of its most interesting applications is related to optical metrology and the characterization of materials through optical techniques. While some of these processes can be explained…

Protein engineering represents a modern approach to generate novel proteins for the different fields of biotechnology. Here, we report about an 8-day laboratory activity in which students generate enzyme variants to degrade the herbicide glyphosate. The students conduct a true research experiment in an important field (bioremediation by novel,…

An upper-division undergraduate- or graduate-level laboratory experiment, challenging students to identify bovine serum albumin, equine myoglobin, bovine calmodulin, and bovine cytochrome c, uses four methods of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS): linear positive, in-source decay, peptide…

The Leidenfrost nanochemistry synthesis of gold colloids was introduced in this "Journal" as an advanced method to synthesize gold nanoparticles during an undergraduate nanochemistry research project. When trying to repeat these experiments in the laboratory, we experienced difficulties in the synthesis of the gold nanoparticles since…

In a classical electronic laboratory, there is an experiment where a diode is connected in a series with a resistor and a variable DC voltage source in order to draw the characteristic I-V curve of the diode. Input voltage is gradually increased starting from 0 V, and the potential difference between the diode's terminals is read by using a…

BYOL (Bring Your Own Lime), a novel laboratory experiment, is introduced in this paper. Students are encouraged to bring affordable household and grocery store chemicals into the classroom. The Bring Your Own Chemical (BYOC) concept demonstrates to students that food and household products are chemicals too. Citruses are often used to highlight…