【推荐1】Egypt is home to more than 100 pyramids, including the landmark Giza pyramid which is the last-standing ancient wonder of the world. It is an example of the wisdom and skills of ancient development. The Great Pyramid of Giza has stood tall since the 26th Century BC, and took 27years to build, with around 2.3 million blocks of stone weighing 6 million tons.

Giza is actually made up of three pyramids, Khufu, Khafre, and Menkaure—each one is named after a pharaoh (法老). Now, scientists are using High Energy Physics to scan (扫描) the Khufu structure at Giza. The new technology scans deeper into the pyramid than before, and then maps its inside structure.

What we see now is only the central structure of the Great Pyramid. Although the pyramid has been studied closely for centuries, there are two mysterious holes that have kept archaeologists puzzled.

One is around 98 feet long and 20 feet high and could be one large space or several rooms, according to scans of the pyramid, while the other is much smaller, just beyond the north face of the pyramid. Archaeologists are not sure what either space functioned as; the most exciting possibility is that the larger space is the hidden room to keep Khufu, who governed from around 2551BC to 2528BC.

Finding holes in pyramids isn’t unusual, though. Nowadays, though, we have the technology to find out, compared to days gone by when examinations would have to blow up the pyramids to explore.

“Since the instruments that are used are very large, they cannot be placed inside the pyramid, and therefore our approach is to put them outside and meticulously move them along the base. In this way, we can build up the required data set,” the team wrote in the paper. The technology is so precise that scientists may be able to even tell objects within the hole.

【推荐2】Droughts are one of a farmer’s most feared threats. And in our warming climate, the risk of drought has been climbing. Anticipating a drier future, two American teen engineers have been investigating how to help farmers keep their crops from getting dangerously thirsty.

John Benedict, 16, has seen lots of droughts. As a sophomore at Clovis North High School, he wanted to help farmers save their plants from being dried. To measure a plant's drought stress more directly, he built a small robotic arm and used it to measure the light reflecting off of bell peppers. As plants get dry, the way they reflect sunlight changes very slightly. It’s not something that our eyes can see. But it is something a robot could detect. At the same time, his robot measured soil moisture and temperature. With these data, he built a computer model. It predicts which plants will be suffering from thirst faster.

It’s also important to make sure that no irrigation water is wasted. That’s why Arya Tschand, 17, has been launching his drone into the sky. This senior at High Technology High School, aims to help poor farmers like the ones he saw while traveling in India. The teen’s drone hovers over plants and measures their color. Using a computer model, Arya taught the drone to predict how thirsty a plant was based on the color of its leaves. According to that color, the drone then sends a signal to an irrigation system on the ground, which adjusts how much water it sends out to plants.

In areas with drought, where every drop matters, farmers can’t afford to waste any moisture. Just like John, his next step is to scale up his project. In the meantime, he has applied for a patent on his system.

【推荐3】The 31,000-year-old skeleton (骨骼) of a young adult found in Indonesia reveals the oldest known evidence of an amputation (截肢), according to a new study.

“We were exploring a cave in Borneo, in a rainforest region, for some of the earliest rock art in the world, when we came across the burial site and the skeleton, which then excited our curiosity,” said Tim Maloney, the study’s lead researcher. Though much of the skeleton was complete, it missed its left foot and the lower part of its left leg, he explained. After examining the remains, the researchers concluded the foot bones weren’t lost in the site or in an accident — they were carefully removed. The remaining leg bone showed a clean cut.

Researchers believed the find presents a remarkable deed. It’s tricky and demanding to prevent infection in amputations, even to this day. Yet more than 30,000 years ago someone was able to handle it. Researchers didn’t know what tool was used to cut the body parts, but they assumed a sharp stone tool may have made the cut. What seems certain is that the patient enjoyed great post-operative care for considerable time, for the person appeared to have lived for around six to nine more years after being disabled.

The operation’s good end result is not pure chance. It implies that the person who performed the operation had some understanding of antimicrobial (抗菌的) medicine. In this respect, their lifestyle and forest environment might have proved to be advantages. “Given these people lived in an area with many medicinal plants, there is a strong case to guess that adapting to this environment may have boosted the development of advanced medical knowledge,” Maloney said.

The surgery rewrites the history of human medical developments. Before this find, the earliest example of amputation had been in a French farmer from almost 7,000 years ago. Researchers had believed advanced medical practice developed around 10,000 years ago, as humans settled down into agricultural societies. But this study adds to evidence that humans started caring for each other’s health long before that.