Browse Articles

Cathodal Galvanotaxis: The Effect of Voltage on the distribution of Tetrahymena pyriformis

Zheng et al. | Jun 10, 2019

Cathodal Galvanotaxis: The Effect of Voltage on the distribution of <em>Tetrahymena pyriformis</em>

The surface of the unicellular eukaryote, Tetrahymena pyriformis, is covered with thousands of hair-like cilia. These cilia are very similar to cilia of the human olfactory and respiratory tracts making them model organisms for studying cilia function and pathology. The authors of this study investigated the effect of voltage on T. pyriformis galvanotaxis, the movement towards an electrical stimulus. They observed galvanotaxis towards the cathode at voltages over 4V which plateau, indicating opening of voltage gated-ion channels to trigger movement.

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Redesigning an Experiment to Determine the Coefficient of Friction

Hu et al. | Jun 27, 2016

Redesigning an Experiment to Determine the Coefficient of Friction

In a common high school experiment to measure friction coefficients, a weighted mass attached to a spring scale is dragged across a surface at a constant velocity. While the constant velocity is necessary for an accurate measurement, it can be difficult to maintain and this can lead to large errors. Here, the authors designed a new experiment to measure friction coefficients in the classroom using only static force and show that their method has a lower standard deviation than the traditional experiment.

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Converting SiO2 wafers to hydrophobic using chlorotrimethylsilane

Lee et al. | Aug 20, 2024

Converting SiO<sub>2</sub> wafers to hydrophobic using chlorotrimethylsilane

Semiconductors are the center of the fourth industrial revolution as they are key components for all electronics. Exposed wafers made of silicon (Si), which can easily oxidize, convert to silicon dioxide (SiO2). The surface of SiO2 wafers consists of many Si-OH bonds, allowing them to easily bond with water, resulting in a “wet” or hydrophilic condition. We sought to determine a way to modify the surface of SiO2 wafers to become hydrophobic to ensure safe wet cleaning.

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The most efficient position of magnets

Shin et al. | Mar 28, 2024

The most efficient position of magnets
Image credit: immo RENOVATION

Here, the authors investigated the most efficient way to position magnets to hold the most pieces of paper on the surface of a refrigerator. They used a regression model along with an artificial neural network to identify the most efficient positions of four magnets to be at the vertices of a rectangle.

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Formation and sticking of air bubbles in water in d-block containers

Gupta et al. | Jun 21, 2021

Formation and sticking of air bubbles in water in d-block containers

Bubbles! In this study, the authors investigate the effects that different materials, temperature, and distance have on the formation of water bubbles on the surface of copper and steel. They calculated mathematical relations based on the outcomes to better understand whether interstitial hydrogen present in the d-block metals form hydrogen bonds with the water bubbles to account for the structural and mechanical stability.

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Harvesting Atmospheric Water

Greenwald et al. | Jul 10, 2020

Harvesting Atmospheric Water

The objective of this project was to test various materials to determine which ones collect the most atmospheric water when exposed to the same environmental factors. The experiment observed the effect of weather conditions, a material’s surface area and hydrophilicity on atmospheric water collection. The initial hypothesis was that hydrophobic materials with the greatest surface area would collect the most water. The materials were placed in the same outside location each night for twelve trials. The following day, the materials were weighed to see how much water each had collected. On average, ribbed plastic collected 10.8 mL of water per trial, which was over 20% more than any other material. This result partially supported the hypothesis because although hydrophobic materials collected more water, surface area did not have a significant effect on water collection.

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