If a human can get an artificial limb, why not an animal? Easier said than done however, as while there is a tremendous amount of ongoing research for human artificial limbs, there is hardly any for animals.

But Dr Tapesh Mathur, a vet living in Jaipur, did not want to wait around anymore. He is credited with making the “Krishna Limb”, India’s first artificial limb for animals. Tapesh has been designing artificial limbs for animals since 2015 and to date, has helped 90 animals adapt to using an artificial limb.

From design to production, Tapesh does all the work by himself at his home-workshop. He provides the artificial limbs for free. Tapesh said, “I could not bear to see their (the cattle’s) pain in shelters. These animals could not voice their anxiety as humans can, but they felt the pain all the same. They waited helplessly for food or for someone to clean them. And I kept thinking if we can help humans walk again, why can’t something similar be done for these animals? Thus I began my research.”

Tapesh designed his first artificial limb for a two-year-old cow named Krishna, who learnt to walk using the limb. Producing these artificial limbs wasn’t an easy task initially, and Tapesh required raw material, which was expensive. Polypropylene, which is used for manufacturing artificial limbs, is only supplied in large quantities by suppliers, and Tapesh had to source it from Mumbai using his own savings.

Now, Tapesh designs customisable artificial limbs for different animals. “We generally work with cows, horses, and dogs, but have started receiving applications for other animals as well. Recently, we got a request for a limb for a pet parrot. We are still working on the design.”

There are certain steps involved in designing. First, Tapesh takes the necessary measurements, based on which the artificial limb is shaped. The real challenge comes when Tapesh has to visit animals living in remote areas as his patients often cannot be brought to him. Once the artificial limb is ready, Tapesh has to visit the animal and attach it for free.

“If you look up in the sky, you probably see, at some point, a plane. And behind that plane are white lines. And that’s what we call contrails(航迹云),” said Mare Stettler, an Imperial College London engineer. It’s believed that planes account for about 3 percent of the climate-changing carbon dioxide release we add to the atmosphere and are warming the planet in another way.

Contrails are made up of ice crystals(冰晶) that form when plane engines release exhaust that hits the cold air. The ice crystals reflect incoming light from the sun back into space, which has a cooling effect on the atmosphere. But contrails also stop heat coming up from the ground from escaping into space. It’s reflected back down toward the ground. And so that’s a warming effect.

Stettler said, “On balance, contrails warm the atmosphere more than they cool it. And that’s primarily because the cooling effect due to reflecting of sunlight can only happen during the day when the sun’s shining, while the warming effect due to trapping of outgoing heat happens all of the time. Some contrails can form clouds that last for up to 18 hours. During that time, they spread out, trapping even more heat. This process allows contrails to warm the earth about as much as the carbon dioxide release from planes.”

“By changing the altitude only by a couple of thousand feet, either up or down, it would no longer form a contrail. And so what we found in the study was that by changing the altitude of less than 2 percent of flights, we could actually eliminate just under 60 percent of the warming effect due to contrails,” added Stettler. This improved understanding of how to manage contrails presents an opportunity for the airline industry to reduce its global environmental impact.