A new set of liquid-handling robots—made from the Lego Mindstorms robotics kit and a cheap, easy-to-find syringe—can transfer precise amounts of fluids among flasks, test tubes, and experimental dishes.
The robot approaches the performance of automation systems found at university at biotech labs.
“We really want kids to learn by doing,” says Ingmar Riedel-Kruse, assistant professor of bioengineering at Stanford University, who led the team that reports its work in the journal PLOS Biology.
“We show that with a few relatively inexpensive parts, a little training, and some imagination, students can create their own liquid-handling robots and then run experiments on it—so they learn about engineering, coding and the wet sciences at the same time,” says Riedel-Kruse, who is also a member of Stanford Bio-X.
The ‘wet sciences’
These robots are designed to pipette fluids from and into cuvettes and multiple-well plates—types of plastic containers commonly used in laboratories. Depending on the specific design, the robot can handle liquid volumes far smaller than one microliter, a droplet about the size of a single coarse grain of salt. Riedel-Kruse believes that these Lego designs might even be useful for specific professional or academic liquid-handling tasks where related robots cost many thousands of dollars.
His overarching idea is to enable students to learn the basics of robotics and the wet sciences (biology, chemistry, medicine) in an integrated way. Students learn STEM skills like mechanical engineering, computer programming, and collaboration while gaining a deeper appreciation of the value of robots in life sciences experiments.Kids are ‘natural scientists’ with live fish in class
Riedel-Kruse says he drew inspiration from the so-called constructionist learning theories, which advocate project-based discovery learning where students make tangible objects, connect different ideas, and areas of knowledge and thereby construct mental models to understand the world around them. One of the leading theorists in the field was Seymour Papert, whose 1980 book Mindstorms was the inspiration for the Lego Mindstorms sets.
“I saw how students and teachers were already using Lego robotics in and outside school, usually to build and program moving car-type robots, and I was excited by that—and the kids obviously as well,” he says. “But I saw a vacuum for bioengineers like me. I wanted to bring this kind of constructionist, hands-on learning with robots to the life sciences.”‘It’s kind of easy’
In their paper, the team offers step-by-step building plans and several fundamental experiments targeted to elementary, middle, and high school students. They also offer experiments that students can conduct using common household products like food coloring, yeast, or sugar. In one experiment, colored liquids with distinct salt concentrations are layered atop one another to teach about liquid density. Other tests measure whether liquids are acids like vinegar or bases like baking soda, or which sugar concentration is best for yeast. Yet another experiment uses color-sensing light meters to align color-coded cuvettes.
The coding aspect of the robot is elementary, Riedel-Kruse says. A simple programming language allows students to place symbols telling the robot what to do: Start. Turn motor on. Do a loop. And so forth. The robots can be programmed and operated in different ways. In some experiments, students push buttons to actuate individual motors. In other experiments, students preprogram all motor actions to watch their experiments executed automatically.Students interact with live cells in online bio lab
“It’s kind of easy. Just define a few parameters and the system works,” he says, adding, “These robots can support a range of educational experiments and they provide a bridge between mechanical engineering, programming, life sciences, and chemistry. They would be great as part of in-school and afterschool STEM programs.”Open-source instructions
Riedel-Kruse says these activities meet several important goals for promoting multidisciplinary STEM learning as outlined by the Next Generation Science Standards (NGSS) and other national initiatives. He stresses the cross-disciplinary instruction value that integrates robotics, biology, chemistry, programming, and hands-on learning in a single project.
The team has co-developed these activities with summer high school students and a science teacher, and then tested them with elementary and middle school students over the course of several weeks of instruction. These robots are now ready for wider dissemination to an open-access community that can expand upon the plans, capabilities, and experiments for this new breed of fluid-handling robots, and they might even be suitable to support certain research applications.
“We would love it if more students, do-it-yourself learners, STEM teachers, and researchers would embrace this type of work, get excited, and then develop additional open-source instructions and lesson plans for others to use,” Riedel-Kruse says.
See the PLOS Biology paper and Riedel-Kruse’s lab website for materials and instructions.
Source: Stanford University
Scientists are challenging the prevailing theory that the unique nature of Earth’s iron was the result of how its core formed billions of years ago.
Certain heavy forms of iron, known as isotopes, are higher on Earth than in other bodies in the solar system.
A new study, published in Nature Communications, suggests that the iron’s isotopic signature developed later in Earth’s history, possibly created when Earth and another planetary body collided with enough force to vaporize the lighter iron isotopes, drawing a disproportionate amount of heavy iron isotopes to Earth’s crust from its mantle.
Iron is one of the most abundant elements in the solar system, and researchers say understanding it is key to figuring out how Earth and other celestial bodies formed.
“The Earth’s core formation was probably the biggest event affecting the Earth’s history.”
Researchers compared the ratio of the heavier iron isotope Fe-56 to the lighter Fe-54 for Earth and extraterrestrial rocks, including those from the moon, Mars, and ancient meteorites. The ratio is significantly higher for Earth rocks than for extraterrestrial rocks, all of which have an identical ratio. The new study attempts to explain how that happened.
“The Earth’s core formation was probably the biggest event affecting the Earth’s history,” says Jung-Fu Lin, professor of geosciences at the University of Texas at Austin and coauthor of the paper. “In this study we say that there must be other origins than the Earth’s formation for this iron isotopic anomaly.”Heat from Earth’s core may drive plate tectonics
Scientists re-created the high pressure that characterized the conditions on Earth during the formation of its core by using a diamond anvil cell—a device capable of recreating pressures that exist deep inside planets—to synthesize processes that would not be discernible otherwise.
The authors recreated the high pressure that characterized the conditions on Earth during the formation of its core. To do this, the researchers used a diamond anvil cell—a device capable of recreating pressures that exist deep inside planets—and were able to synthesize processes that would not be discernible otherwise.
“The diamond anvil cell has been used in this way before, but the difficulty is getting correct numbers,” says coauthor Nicolas Dauphas, professor of geophysical sciences at the University of Chicago.Did molten iron ‘percolate’ to form Earth’s core?
“That requires great care in data acquisition and treatment because the signal the diamond anvil gives off is very small. One has to use sophisticated mathematical techniques to make sense of the measurements.”
The experiment sought to show that the high levels of heavy iron isotopes in Earth’s mantle likely occurred during the formation of Earth’s core. But the measurements show that the theory doesn’t work, “so the solution to this mystery must be sought elsewhere,” Dauphas says.
Other researchers from the University of Chicago, Argonne National Laboratory, Sorbonne University and the Museum National d’Histoire Naturelle in France, the Center for High Pressure Science and Technology Advanced Research in China, and the University of Illinois at Urbana-Champaign are coauthors of the study.
The National Science Foundation, Center for High Pressure Science and Technology Advanced Research, Department of Energy, and National Aeronautics and Space Administration funded the work.
Source: University of Chicago
The post Did a collision leave Earth with its iron anomaly? appeared first on Futurity.