Two groundbreaking publications by Bar-Ilan University investigators and their US colleagues – one from nearly 20 years ago and a second published in 2010 – continue to top the list of the “most read articles” in two of the world’s most prestigious scientific journals in chemistry.
The first article, “NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities,” was published on October 17, 1997 in the Journal of Organic Chemistry. In the article, Dr. Hugo Gottlieb, Dr. Vadim Kotlyar and Prof. Abraham Nudelman of BIU’s chemistry department presented useful data for solving a day-to-day problem – the identification of trace residues of organic solvents in the routine use of nuclear magnetic resonance (NMR) as an aid for organic chemistry.
The data presented in the article are downloaded daily by many scientists and have become invaluable to organic chemists worldwide and anyone experimenting with NMR analysis. Furthermore, the data have been attached to large numbers of NMR instruments worldwide and incorporated into major catalogs and manuals by the manufacturers of NMR instruments.
In addition, a second article expanding on the data was published in the journal Organometallics
in 2010. The article, entitled “NMR Chemical Shifts of Trace Impurities: Common Laboratory Solvents, Organics, and Gases in Deuterated Solvents Relevant to the Organometallics,” was a joint publication of investigators from the University of Washington and California Institute of Technology (Caltech), in collaboration with Gottlieb and Nudelman.
The authors believe the data will continue to be of value to future students and all those involved in NMR, and is therefore expected to remain in “most-read” status for years to come. Both journals are published by the American Chemical Society and are considered top journals in their field.GECKO-LIKE GRIPPER TO CLEAN UP SPACE DEBRIS
Right now, about 500,000 pieces of human-produced debris are whizzing around in space, orbiting our planet at incredible speeds and posing a threat to satellites, space vehicles and astronauts aboard those vehicles. What makes tidying up especially challenging is that the debris exists in space.
Suction cups don’t work in a vacuum and conventional sticky substances like tape are largely useless because the chemicals they rely on can’t withstand the extreme temperature swings. Magnets work only on objects that are magnetic.
Most proposed solutions, including debris harpoons, either require or cause forceful interaction with the debris, which could push those objects in unintended, unpredictable directions.
To tackle the mess, researchers from Stanford University and NASA’s Jet Propulsion Laboratory (JPL) have designed a new kind of robotic gripper to grab and dispose of the debris, featured recently in the journal Science Robotics
“What we’ve developed is a gripper that uses gecko-inspired adhesives,” said mechanical engineering Prof. Mark Cutkosky, the senior author of the paper. “It’s an outgrowth of work we started about 10 years ago on climbing robots that used adhesives inspired by how geckos stick to walls.”
The group tested their gripper and smaller versions of it in their lab and in multiple zero-gravity experimental spaces, including the International Space Station. Promising results from those early tests have led the researchers to wonder how their grippers would fare outside the station, a likely next step.
“There are many missions that would benefit from this, like rendezvous and docking and orbital debris m i t i g a t i o n , said Dr. Aaron Parness of JPL. “We could also eventually develop a climbing robot assistant that could crawl around on the spacecraft, doing repairs, filming and checking for defects.”
The adhesives developed by the Cutkosky lab have previously been used in climbing robots and even a system that allowed humans to climb up certain surfaces. They were inspired by geckos, which can climb walls because their feet have microscopic flaps that, when in full contact with a surface, create weak intermolecular forces between the feet and the surface resulting from subtle differences in the positions of electrons on the outsides of molecules.
Like a gecko’s foot, the gripper is sticky only if the flaps are pushed in a specific direction – but making it stick only requires a light push in the right direction. This is a helpful feature for the kinds of tasks a space gripper would perform.
The group first tested the gripper in the Cutkosky lab. They closely measured how much load the gripper could handle, what happened when different forces and torques were applied and how many times it could be stuck and unstuck. Through their partnership with JPL, the researchers also tested the gripper in zero-gravity environments.
Next steps for the gripper involve readying it for testing outside the space station, including creating a version made of longer-lasting materials able to hold up to high levels of radiation and extreme temperatures. The current prototype is made of laser-cut plywood and includes rubber bands, which would become brittle in space. The researchers will have to make something sturdier for testing outside the ISS, likely designed to attach to the end of a robot arm.
Cutkosky also hopes that they can manufacture larger quantities of the adhesive at a lower cost. He imagines that someday the gecko-inspired adhesive could be as common as Velcro.DOGS ARE GENEROUS WITH THEIR FOOD
Generosity, even among family members, had long been considered to be a specifically human characteristic. Yet rats, chimpanzees and other animals also exhibit similar behavior. Rachel Dale and colleagues in Vienna had already shown that dogs also share food rewards with other dogs. Using a bar-pulling task, the dogs delivered the treats to partner dogs – especially if these were already familiar to them. A new study by the research team now used a more complex task set-up to confirm dogs’ prosocial behavior.
The increased complexity of the task influenced the readiness with which the dogs delivered a food reward to another animals. Unfamiliar dogs were rewarded nearly three times less often than familiar ones. The higher level of complexity, however, impacted the general frequency of the food delivery.
The behavioral biologists found another significant difference regarding the question whether the presence of a partner was important for the motivation of the test dog. Even when a second dog was present in the testing room without being in the other enclosure, the donor dogs were more motivated to give a food reward. When the test dogs were alone in the room, the number of food deliveries went down.