In this work, the authors investigate the accuracy with which two different population growth models can predict population growth over time. They apply the Malthusian law or Logistic law to US population from 1951 until 2019. To assess how closely the growth model fits actual population data, a least-squared curve fit was applied and revealed that the Logistic law of population growth resulted in smaller sum of squared residuals. These findings are important for ensuring optimal population growth models are implemented to data as population forecasting affects a country's economic and social structure.
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Testing Epoxy Strength: The High Strength Claims of Selleys’s Araldite Epoxy Glues
Understanding the techniques used to improve the adhesion strength of the epoxy resin is important especially for consumer applications such as repairing car parts, bonding aluminum sheeting, and repairing furniture or applications within the aviation or civil industry. Selleys Araldite epoxy makes specific strength claims emphasizing that the load or weight that can be supported by the adhesive is 72 kg/cm2. Nguyen and Clarke aimed to test the strength claims of Selley’s Araldite Epoxy by gluing two steel adhesion surfaces: a steel tube and bracket. Results showed that there is a lack of consideration by Selleys for adhesion loss mechanisms and environmental factors when accounting for consumer use of the product leading to disputable claims.
Read More...Antibacterial Effects of Copper Surfaces
This study examined the ability of copper and copper alloy surfaces to inhibit bacterial growth, which may be help prevent healthcare-associated infections. The authors exposed two non-pathogenic strains of bacteria to different metal plates for varying degrees of time and measured bacterial growth.
Read More...A Temperature-Based Comparison of Compounds Found in Bao Chong Tea, Green Tea, and Black Tea
While tea has a complex history, recently the health benefits of this beverage have come into focus. In this study, researchers sought to compare the levels of caffeine, catechins and L-theanine between different types of tea using NMR spectroscopy. Further, the impact of brewing temperature on the release of these compounds was also assessed. Of those tested, Bao Chong tea had the highest levels of these compounds. Brewing temperatures between 45ºC and 75ºC were found to be optimal for compound release. These results can help consumers make informed choices about their tea preparation and intake.
Read More...Breaking the Ice: A Scientific Take on the Ice Melting Abilities of Household Salts
The use of salt to melt ice is a common and important practice to keep roadways safe during winter months. However, various subtypes of salt differ in their chemical and physical properties, as well as their environmental impact. In this study, the authors measure the effectiveness of different salts at disrupting ice structures and identify calcium chloride as the most effective.
Read More...Contrast-Enhanced Magnetic Resonance Imaging at Earth’s Magnetic Field Using Trace Gd3+ and Ho3+ Salts
In this study, the authors explore contrast-enhanced magnetic resonance imaging at Earth's field.
Read More...Slowing ice melting from thermal radiation using sustainable, eco-friendly eggshells
The authors looked at the ability of eggshells to slow ice melting. They found that eggshells were able to increase ice melting time when crushed showing that they were an effective thermal barrier.
Read More...Creating a drought prediction model using convolutional neural networks
Droughts kill over 45,000 people yearly and affect the livelihoods of 55 million others worldwide, with climate change likely to worsen these effects. However, unlike other natural disasters (hurricanes, etc.), there is no early detection system that can predict droughts far enough in advance to be useful. Bora, Caulkins, and Joycutty tackle this issue by creating a drought prediction model.
Read More...Digestion products of bread and cheese cause addictive behavior in a planaria model
The authors looked at two peptides, gluteomorphin and casomorphin, that are present after the digestion of bread and cheese. As these peptides can bind opioid receptors the authors want to know if they could be addictive in the same way as conventional opioids (i.e., morphine) are known to be. Their results in a planaria model suggest that both of these peptides are addictive.
Read More...Solubility of graphite and the efficacy of using its dissolved form as a conductive paste
This study explored the use of graphite's conductivity for circuit boards by creating a conductive paste through exfoliation with organic solvents and sonication. The combination of acetone and sonication was found to be the most effective, producing a high-conductivity paste with desirable properties such as a low boiling point. While not a replacement for wires, this conductive paste has potential applications in electronics and infrastructure, provided that key engineering challenges are addressed.
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