Comprehensive curricula are described for middle and high school classrooms built around the synthesis of biodegradable calcium alginate capsules prepared from food-safe chemicals. Experiments and activities question whether calcium alginate capsules are a viable alternative to single-use water bottles and consider what characteristics are…

Active learning and practices are strongly encouraged or made mandatory by local, national, and European organizations. Therefore, we set up an interactive practical classroom, engaging all of the attending students of the year (n = 47). Each student was assigned a physiological role (marked on a cardboard sign) in the following events:…

Rare events meta-analyses of randomized controlled trials (RCTs) are often underpowered because the outcomes are infrequent. Real-world evidence (RWE) from non-randomized studies may provide valuable complementary evidence about the effects of rare events, and there is growing interest in including such evidence in the decision-making process.…

The purpose of this experiment was to create a simple and inexpensive flame photometer to measure the concentration of sodium in beverages, such as Gatorade. We created a nebulizer using small tubing and sprayed the sample into the base of a Bunsen burner. Adjacent to the flame was a photodiode with a filter specific for the emission of the sodium…

This case-control study investigated nutrient intake, healthy eating index with 10 items on foods and nutrients, on 3-day food diaries and anthropometric measurements in 105 children with autism spectrum disorder and 495 typically developing children (6-9 years) in Valencia (Spain). Children with autism spectrum disorder were at a higher risk for…

Background: The Healthy, Hunger-Free Kids Act of 2010 (HHFKA) directed the US Department of Agriculture (USDA) to revise school meal standards to increase healthy food offerings. A critical stakeholder in the implementation of standards is Food Service Directors (FSDs). We sought to examine FSDs' perspectives on revised school meal standards to…

The aim of this study was to assess dietary intake, breastfeeding history, weight at birth and current weight in children and adolescents with Down syndrome (DS). Therefore, a cross-sectional, controlled study with 19 DS participants and 19 controls without DS matched by gender and age was performed. Except for vitamin D, a lower or the same…

The Hofmeister series is a recurring trend that ranks ions' abilities to influence various aqueous processes in solution. Herein, a set of project-based experiments was developed for students in an upper-level physical chemistry laboratory to investigate the specific ion effects on the thermodynamics of caffeine partitioning between aqueous and…

Acid--base chemistry is an important and challenging topic for virtually all chemistry students. Recent works have focused on conceptually linking molecular and symbolic representations to experimental evidence for many chemical concepts. In this work we describe a laboratory exercise designed to address students' conceptual challenges regarding…

We present an experiment which was designed to assess the separation technique skills of the gifted high school students who attended the 50th International Chemistry Olympiad 2018. The procedure consists of two synthetic tasks and is also applicable for teaching undergraduates. The haloform reaction of 2-acetonaphthone with sodium hypochlorite in…

Despite extensive conceptualization of ions as hard spheres in most textbooks, solid-state structures are more accurately modeled as overlapping soft spheres that better reflect the size of the ions. The corresponding soft-sphere ionic radii of alkali and halide ions can be empirically established from the partial molar volume of the ions in…

In this experiment, students learn how to find the unknown concentration of sodium acetate using both the graphical treatment of standard addition and the standard addition equation. In the graphical treatment of standard addition, the peak area of the methyl peak in each of the sodium acetate standard solutions is found by integration using…

A novel smartphone microscope can be used to observe the dissolution and crystallization of sodium chloride at a microscopic level. Observation of these seemingly simple phenomena through the microscope at 100× magnification can actually reveal some surprising behavior. These experiments offer the opportunity to discuss some basic concepts such as…

This article describes a ten week long laboratory exercise designed for undergraduate students aimed at enhancing their understanding of physiological and biochemical responses of plants under dehydration stress. Hypothesis was built around previous reports which suggested that exogenous application of certain elicitors leads to transient…

This paper revisits the tie-dyeing process through a bioinspired and safer alternative to nucleophilic aromatic substitution (S[subscript N]Ar) reactions for an introductory organic chemistry laboratory. The simple and straightforward experiment provides students with an opportunity to gain practical experience in conducting a chemical reaction in…