Laboratory Exercise For Students Research Articles

Fresnel–Arago laws: an easily feasible demonstration and laboratory exercise for students

The basic premise of this work was to create a simple experimental setup for the demonstration of Fresnel–Arago laws and the realization of an experimental exercise. An Iceland calcite is used as a beam splitter, and by adding a diverging lens (commonly used to magnify the image), a large image of overlapping spots is obtained at a short distance, visible to a wide audience. Additionally, by placing a diverging lens at different distances from the calcite, the level of the spots overlapping can be changed. The interference image is photographed by a smartphone and processed by one of the available applications for quantitative image processing. The experiment was carried out using red and green laser light. The same setup, with a diverging lens, also allows the reconstruction of the original Fresnel and Arago experiment with a thin metal cylinder. Quick and easy construction, relatively simple processing of the interference image, without the use of expensive devices (CCD camera, beam splitter, beam expander), and the good agreement between the nominal and measured laser light wavelengths, make this setup very suitable for realization as a student exercise for undergraduate and master’s students.

Characterization of proteinous coagulant in Moringa tree seeds for water purification: Stepwise laboratory exercise for high-school students.

Coagulation is an important process in the context of water purification; and the seed protein of the moringa tree (Moringa oleifera) is a remarkably effective coagulant. The laboratory course described here is designed to provide high-school students with a stepwise, hands-on experience in investigating the protein-rich coagulant found in Moringa seeds. First, the seed powder was applied to model polluted water containing fine clay, food dyes, copper sulfate, and bacteria. This treatment changed the polluted water into clear water via coagulation; all students were convinced that the coagulation-inducing agent was a thermostable cationic protein. Finally, basic biochemical techniques (e.g., chromatographic separation and electrophoresis) were used to show that the target coagulant is a dimeric protein composed of 6.5 and 4.5 kDa subunits. Overall, this made it possible for the students to gain a deeper understanding (more comprehensive than the information taught in formal classes) of protein structure and its real-world implications. This stepwise exercise can be applied to research-based learning programs in high school, as it is an effective learning tool.

Teaching Innovation in STEM Education Using an Unmanned Aerial Vehicle (UAV)

The use of unmanned aerial vehicles (UAVs) has increased in the science, technology, engineering, and mathematics (STEM) professions. This means there is a growing need to integrate UAV training into STEM education. This study aimed to develop and evaluate a UAV education module and laboratory exercise for natural resource science students. The study used a series of reusable learning objects (RLOs) to assess students’ prior knowledge of remote sensing and UAVs. Students were taught the steps of UAV data acquisition and processing through lectures and UAV simulation videos. Students applied this knowledge by completing a laboratory exercise that used previously collected UAV data. Student knowledge retention and understanding were evaluated using an online quiz to determine the effectiveness of the education module. The average quiz score was 92%, indicating that the UAV laboratory exercise effectively taught students about UAV data acquisition and processing for natural resource research. Overall, students expressed positive opinions about the UAV education module. Student feedback indicated that the laboratory exercise was engaging, but some students would have preferred a hands-on experience for some parts of the exercise. However, in-person UAV instruction may not be accessible for all educators because of UAV cost or lack of instructor training. This study provides educators with crucial recommendations for designing UAV exercises to improve access to UAV-related educational content. This study indicates that online training can effectively introduce students to UAVs. Given the wide range of UAV uses across STEM fields, students in many STEM disciplines would benefit from UAV education.

RMIT University’s practical space weather prediction laboratory

Space weather is a key component in the daily operation of many technological systems and applications, including large-scale power grids, high-frequency radio systems, and satellite systems. As the international space sector continues to boom, accessible space weather products, tools and education are increasingly important to ensure that space actors (both old and new) are equipped with the knowledge of how space weather influences their activities and applications. At RMIT University, the initiative was taken to develop a Space Weather Prediction Laboratory exercise for students as part of its new offering of a Bachelor’s Degree in Space Science in 2020. This new Space Weather Prediction Lab exercise is offered as part of an undergraduate course on “Space Exploration”, which has a diverse student in-take, including students with no background in physics; a key detail in the design of the Lab. The aims of the Space Weather Prediction Lab were to: (1) provide a short and intense introduction to the near-Earth space environment and its impact on various human technologies; (2) give students “hands-on” training in data analysis, interpretation and communication; and (3) create an immersive space science experience for students that encourages learning, scientific transparency and teamwork. The format of the lab that was developed can be easily scaled in difficulty to suit the students’ technical level, either by including more/less space weather datasets in the analysis or by analyzing more/less complicated space weather events. The details of the Space Weather Prediction Lab developed and taught at RMIT in 2020, in both face-to-face and online formats, are presented.

How much water is in a mouthful, and how many mouthfuls should I drink? A laboratory exercise to help students understand developing a hydration plan

Preventing impairments in athletic performance is an important concept for students that are preparing for careers that involve working with athletes. Gaining hands on, laboratory-based experience in measuring exercise induced dehydration can help students understand how to help athletes prevent dehydration induced impairment in performance. This article describes a laboratory exercise for junior and senior students in a sports nutrition class, in which the students measure changes in body mass (as a measure of dehydration) due to 40 min of moderate-intensity exercise and 40 min of vigorous-intensity exercise. The students also measure how much water is in a mouthful from a sports bottle and from a drinking fountain. The students then calculate how many mouthfuls are necessary to replace exercise induced fluid losses. This laboratory exercise has been well received by students and has improved performance on the test regarding hydration.

Sodium carbonate versus borate buffer for lactase quenching, laboratory work.

A laboratory exercise for undergraduate advanced students of enzymology and biocatalysis is presented. Since enzyme assays can be quenched or continuous, this experiment compares the performance of two quenching agents for lactase, in a continuous setup. Enzymatic activity of β-galactosidase (Aspergillus oryzae) was determined based on the release of 4-nitrophenol from 4-nitrophenyl β-D-galactopyranoside using a microplate reader. Sodium carbonate and borate buffer were tested as quenching agents, and experimental control was the unstopped assay. Based on released 4-nitrophenol, enzyme activity, and rate constant k, the students could assess the performance of each termination agent. The experiment promotes disciplinary and transversal competencies, including research-based learning, critical thinking, and introduce the students to high-throughput techniques that are common in the research and development environment.

Decontamination of Wastewater Using Activated Biochar from Agricultural Waste: A Practical Experiment for Environmental Sciences Students

Safe and high-quality water is essential from both the health and environmental perspectives. Water quality is so important that the United Nations has included water in the 17 Sustainable Development Goals of the 2030 Agenda for Sustainable Development. Thus, the adequate control and treatment of water are necessities. These tasks must be performed by a wide variety of professionals, including chemists, technicians, environmental scientists, .... Regarding the last group, one competency that they must develop throughout their university training is the ability to implement an environmental management system. Regarding water management, in addition to its well-known positive effect on the environment, wastewater treatment allows for the acquisition of water that is suitable for human consumption and use in agriculture. The relevant wastewater treatments are not complex, but they involve the participation of practitioners of several areas of study including engineering, chemistry, microbiology, .... This paper describes a laboratory exercise for students seeking university degrees in environmental sciences that aims to instruct them about wastewater treatment. Specifically, the experiment involves the decontamination of water polluted with the common textile dye methylene blue. The experiment is performed with different samples of activated carbon of agricultural origin (sustainable), and the results are compared with those obtained vs a carbon of petrochemical origin. The characterization of the decontamination process is performed via spectrophotometric measurements of the presence of methylene blue. The results obtained following the use of different quantities of adsorbent material are also compared.

A low-cost laboratory demonstration of the effects of temperature on the metabolism of an aquatic poikilotherm

ABSTRACT While metabolism is a fundamental process in physiology, the measurement of metabolism by living animals often requires specialized and expensive equipment. In 2016, I developed a novel laboratory exercise for animal physiology students where students were able to observe the effects of temperature and long-term temperature acclimation on the physiology of the Eastern grass shrimp, Palaemonetes paludosus. In this lab, grass shrimp were housed for 1 week at one of three temperatures, 20°C, 24°C, and 28°C. While grass shrimp encounter temperatures considerably colder than this in the wild, we were limited by the temperatures we could achieve without access to aquarium chillers. The students then moved shrimp into water of different temperatures and measured metabolic rates indirectly using heart rate and oxygen consumption. The initial results showed noticeable shifts in baseline metabolic rate over a relatively short, 2 week long acclimation period. In both heart rate and oxygen consumption, metabolic rates climbed predictably with temperature, consistent with the literature on responses in ectotherms. Also, consistent with the literature, the shrimp that were acclimated to warmer temperatures downregulated their metabolism to compensate, showing the lower metabolic rate at all three temperatures.

CRISPR/Cas9 in yeast: a multi-week laboratory exercise for undergraduate students

CRISPR/Cas9 in yeast: a multi-week laboratory exercise for undergraduate students

Simple and rapid system for two-dimensional gel electrophoresis technique: A laboratory exercise for high school students.

Polyacrylamide gel electrophoresis (PAGE) is the most classical technique favored worldwide for resolution of macromolecules in many biochemistry laboratories due to its incessant advanced developments and wide modifications. These ever-growing advancements in the basic laboratory equipments lead to emergence of many expensive, complex, and tricky laboratory equipments. Practical courses of biochemistry at high school or undergraduate levels are often affected by these complications. Two dimensional gel electrophoresis technique (2D-PAGE) used for resolving thousands of proteins in a gel is a combination of isoelectric focusing (first dimension gel electrophoresis technique) and sodium-dodecylsulphate PAGE (second dimension gel electrophoresis technique or SDS-PAGE). Two different laboratory equipments are needed to carry out effective 2D-PAGE technique, which also invites extra burden to the school laboratory. Here, we describe a low cost, time saving and simple gel cassette for protein 2D-PAGE technique that uses easily fabricated components and routine off-the-shelf materials. The performance of the apparatus was verified in a practical exercise by a group of high school students with positive outcomes. © 2018 by The International Union of Biochemistry and Molecular Biology, 46(3):237-244, 2018.

Single-Step Gene Knockout of the SUC2 Gene in Saccharomyces cerevisiae : A Laboratory Exercise for Undergraduate Students.

This article describes a relatively straightforward procedure to knock out the gene that encodes the invertase enzyme in baker’s yeast. The SUC2 gene, which encodes for the invertase enzyme, is knocked out by a single-step PCR knock out method. The knockout is subsequently confirmed at the genetic level by PCR and agarose gel electrophoresis. The knockout is confirmed at the biochemical level by measuring the activity of the invertase enzyme using a colorimetric assay. This tips and tools article describes an easily scalable, inexpensive, yet challenging research project helping undergraduate students at the Bachelor level to conceptualize the effect of the deletion of a gene encoding an enzyme.

Is the Total Concentration of a Heavy Metal in Soil a Suitable Tool for Assessing the Environmental Risk? Considering the Case of Copper

National legislation concerning soil pollution by heavy metals in different countries is mostly based on the total heavy metal concentration levels allowed in different soils. As soil pollution is an issue of worldwide concern, here we develop a laboratory exercise for students in which they must check the suitability of a total metal concentration for soil pollution assessment. Undertaking two different Cu extractions promotes student discussion about soil pollution by heavy metals: Cu extracted with EDTA and Cu extracted with DTPA. These two extractions are commonly used by the soil science community to estimate the potentially available Cu for plants, which is compared with information about total Cu that is provided to the students. The results of this laboratory exercise demonstrate that the total concentration of Cu in the soil is not suitable for decision-making about whether a soil is polluted. However, establishing reference values from EDTA and DTPA extractions or EDTA/Total and DTPA/Total ratio...

New tricks with aryl Grignards

A time-honored laboratory exercise for students of organic chemistry is to make a Grignard reagent from magnesium metal turnings and an organohalide so that they can then use the resulting nucleophile to forge a new C–C bond. Chemists led by Rice University’s Laszlo Kurti and Brigham Young University’s Daniel H. Ess now report a way to use stalwart aryl Grignard reagents to fashion C–N and C–O bonds. The chemists found that when they reacted aryl Grignard reagents with a bench-stable, bulky N-H oxaziridine, the nucleophiles attacked the compound’s nitrogen group to generate anilines. Blocking the oxaziridine’s nitrogen with a benzyl group prompted the Grignard to attack the compound’s oxygen atom instead, generating a phenol compound (Nat. Chem. 2016, DOI: 10.1038/nchem.2672). “Our method is really plain and simple,” Kurti says. “You take either of these oxaziridine reagents and now you have the freedom to take the same aryl Grignard and make

Use of mushroom tyrosinase to introduce michaelis-menten enzyme kinetics to biochemistry students.

An inexpensive enzyme kinetics laboratory exercise for undergraduate biochemistry students is described utilizing tyrosinase from white button mushrooms. The exercise can be completed in one or two three-hour lab sessions. The optimal amounts of enzyme, substrate (catechol), and inhibitor (kojic acid) are first determined, and then kinetic data is collected in the absence and presence of the inhibitor. A Microsoft Excel template is used to plot the data and to fit the Michaelis-Menten equation to the data to determine the kinetic parameters Vmax and Km . The exercise is designed to clarify and reinforce concepts covered in an accompanying biochemistry lecture course. It has been used with positive results in an upper-level biochemistry laboratory course for junior/senior students majoring in chemistry or biology. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(3):270-276, 2017.

A Proboscis Extension Response Protocol for Investigating Behavioral Plasticity in Insects: Application to Basic, Biomedical, and Agricultural Research

Insects modify their responses to stimuli through experience of associating those stimuli with events important for survival (e.g., food, mates, threats). There are several behavioral mechanisms through which an insect learns salient associations and relates them to these events. It is important to understand this behavioral plasticity for programs aimed toward assisting insects that are beneficial for agriculture. This understanding can also be used for discovering solutions to biomedical and agricultural problems created by insects that act as disease vectors and pests. The Proboscis Extension Response (PER) conditioning protocol was developed for honey bees (Apis mellifera) over 50 years ago to study how they perceive and learn about floral odors, which signal the nectar and pollen resources a colony needs for survival. The PER procedure provides a robust and easy-to-employ framework for studying several different ecologically relevant mechanisms of behavioral plasticity. It is easily adaptable for use with several other insect species and other behavioral reflexes. These protocols can be readily employed in conjunction with various means for monitoring neural activity in the CNS via electrophysiology or bioimaging, or for manipulating targeted neuromodulatory pathways. It is a robust assay for rapidly detecting sub-lethal effects on behavior caused by environmental stressors, toxins or pesticides. We show how the PER protocol is straightforward to implement using two procedures. One is suitable as a laboratory exercise for students or for quick assays of the effect of an experimental treatment. The other provides more thorough control of variables, which is important for studies of behavioral conditioning. We show how several measures for the behavioral response ranging from binary yes/no to more continuous variable like latency and duration of proboscis extension can be used to test hypotheses. And, we discuss some pitfalls that researchers commonly encounter when they use the procedure for the first time.

A proboscis extension response protocol for investigating behavioral plasticity in insects: application to basic, biomedical, and agricultural research.

Insects modify their responses to stimuli through experience of associating those stimuli with events important for survival (e.g., food, mates, threats). There are several behavioral mechanisms through which an insect learns salient associations and relates them to these events. It is important to understand this behavioral plasticity for programs aimed toward assisting insects that are beneficial for agriculture. This understanding can also be used for discovering solutions to biomedical and agricultural problems created by insects that act as disease vectors and pests. The Proboscis Extension Response (PER) conditioning protocol was developed for honey bees (Apis mellifera) over 50 years ago to study how they perceive and learn about floral odors, which signal the nectar and pollen resources a colony needs for survival. The PER procedure provides a robust and easy-to-employ framework for studying several different ecologically relevant mechanisms of behavioral plasticity. It is easily adaptable for use with several other insect species and other behavioral reflexes. These protocols can be readily employed in conjunction with various means for monitoring neural activity in the CNS via electrophysiology or bioimaging, or for manipulating targeted neuromodulatory pathways. It is a robust assay for rapidly detecting sub-lethal effects on behavior caused by environmental stressors, toxins or pesticides.We show how the PER protocol is straightforward to implement using two procedures. One is suitable as a laboratory exercise for students or for quick assays of the effect of an experimental treatment. The other provides more thorough control of variables, which is important for studies of behavioral conditioning. We show how several measures for the behavioral response ranging from binary yes/no to more continuous variable like latency and duration of proboscis extension can be used to test hypotheses. And, we discuss some pitfalls that researchers commonly encounter when they use the procedure for the first time.

From a Laboratory Exercise for Students to a Pioneering Biosensing Technology.

Surface plasmon resonance (SPR) for biosensing was demonstrated 30 years ago. In the present contribution, its general background is described together with the necessary developments both in instrumentation and surface chemistry, leading to the final so-called BIAcore technology. The description is naturally colored by my personal opinion of the developments. SPR for the elucidation of organic mono- and multilayers introduced at the end of the 1970s formed the basis for the first biosensing demonstration of SPR in the beginning of the 1980s. It is pointed out how the need of an up-to-date laboratory exercise for the undergraduate students and the multidisciplinary environment at the Laboratory of Applied Physics at Linköping University led to this demonstration. The initial experiments are touched upon and the further developments at Pharmacia, which led to the BIAcore technology, are described in some details. Some of the present activities in Linköping related to optical biosensing with ubiquitous instrumentation are also described, including SPR detection with a computer screen and a web camera and most recently with a cellular phone.

Affordable hands‐on DNA sequencing and genotyping: An exercise for teaching DNA analysis to undergraduates

In this report, we describe a 5-week laboratory exercise for undergraduate biology and biochemistry students in which students learn to sequence DNA and to genotype their DNA for selected single nucleotide polymorphisms (SNPs). Students use miniaturized DNA sequencing gels that require approximately 8 min to run. The students perform G, A, T, C Sanger sequencing reactions. They prepare and run the gels, perform Southern blots (which require only 10 min), and detect sequencing ladders using a colorimetric detection system. Students enlarge their sequencing ladders from digital images of their small nylon membranes, and read the sequence manually. They compare their reads with the actual DNA sequence using BLAST2. After mastering the DNA sequencing system, students prepare their own DNA from a cheek swab, polymerase chain reaction-amplify a region of their DNA that encompasses a SNP of interest, and perform sequencing to determine their genotype at the SNP position. A family pedigree can also be constructed. The SNP chosen by the instructor was rs17822931, which is in the ABCC11 gene and is the determinant of human earwax type. Genotypes at the rs178229931 site vary in different ethnic populations.

Thermometry as a Teaching Tool for Graphing: A First-Day Introductory Chemistry Laboratory Experiment

Preparing a meaningful laboratory exercise for introductory or general chemistry students to perform, especially on the first day of class, is challenging. Introductory or general chemistry students range from being skilled in laboratory techniques and equipment usage to never having been in a laboratory setting. Subject content can be taught in the laboratory in advance of an associated lecture, but this too is not always popular or practicable. A laboratory exercise is presented that can be taught at the very beginning of the semester. The primary focus is on graphing to investigate the thermal expansion of a liquid, but students can be instructed on recording data precisely from a measuring device, be introduced to the basic physical properties of liquids, practice using a spreadsheet software program for data analysis, and learn good laboratory note-taking. The experiment is appropriate for a first-semester general chemistry course, physical science, or high-school chemistry.

Studying how plants defend themselves: a chemical weapon produced by chilli fruit

Students often prefer to study animals rather than plants, because they see plants as passive, less interesting organisms. This paper proposes a simple hands-on laboratory exercise for high-school students (grade 12) to arouse their interest in learning about plants and to demonstrate to them that plants are active organisms capable of defending themselves. In this classroom exercise, students investigate how a plant responds to an invader. As a model for study, the exercise uses three organisms: red chilli fruit, the yeast biological control agent Saccharomyces cerevisiae, and the pathogenic fungus Rhizopus stolonifer. Students gain basic knowledge about how plants defend themselves against pathogens by observing the physical changes of an infected wound site and by investigating the chemical compounds produced by plants in response to pathogen invasion; they are also encouraged to think critically about using biological control as a means to promote environmentally friendly agricultural practices.