Sugarcane can’t be sweet at both ends… So which end is sweet? ｜ Expo Daily

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Sugarcane cannot be sweet at both ends...then which end is sweet?

Generally in production, when sugarcane matures, relevant inspectors will use a plummeter to measure the density of juice in different internodes at the top, middle and bottom of the sugarcane, and convert it into sugar content.

If the upper part has much less sugar than the lower part, the sugarcane is not fully mature yet and you need to wait for some time; if the difference between the upper and lower parts is not big, the sugarcane has completed sugar accumulation and is fully mature and can be used for sugar making.

So generally speaking, the bottom of the sugar cane is sweeter than the top. This is because during the growth of the sugar cane, sugar is produced through photosynthesis and transported and stored from the top downward. Therefore, the bottom sugar cane near the root accumulates more sugar and tastes sweeter.

In addition, if sugarcane cannot be harvested in time after maturity, or is not processed in time after harvest, the sugarcane will experience "sugar deterioration", that is, the sugar content of the sugarcane will decrease.

This is because there are buds on the nodes of sugarcane, and each bud can grow into a new sugarcane seedling. This is also the main way of asexual reproduction of sugarcane. If not handled in time, the sugar stored in the sugarcane stems will be used for the growth of sugarcane buds, and the sugarcane stems will naturally not be as sweet as before.

Sugarcane and sugar Image source: veer gallery

Toad: You make me sick!

Once the yapple beetle is swallowed into the toad's stomach, it does not quietly wait for its fate to come, but instead launches a wonderful self-rescue operation.

The beetle releases a high-temperature chemical spray, a "breathing fire" effect that is not only self-protective, but also enough to make the toad feel extremely uncomfortable. For the next few minutes, the toad tries to endure the irritation in its stomach, but is often forced to make a shocking choice - vomiting.

The success rate of bombardier beetles' life-or-death escapes is not completely random. The study found that the larger the beetle, the more chemicals it released and the higher its chance of escaping successfully. For toads, the smaller they are, the lower their chemical tolerance is, making it easier for them to spit out beetles.

It's a battle between big and small, so to speak: the small toad can't withstand the beetle's chemical counterattack, while the large beetle has a better chance of escaping in style.

If you are eaten, don't panic, there is always a way out, provided you eat it whole and alive...

Image source: Shinji Sugiura and Takuya Sato

Scientists confirm the origin of the Japanese through genetic comparison

Recently, a joint research team led by the University of Tokyo found that most of the immigrants in Japan's Yayoi period (starting around 3000 BC) and Kofun period (starting around 300 AD) came from the Korean Peninsula. The researchers analyzed the complete genomes of individuals in the Yayoi period and found that the results were most similar to those of the Korean Peninsula population.

From the time when prehistoric civilizations emerged in the Japanese archipelago until 3000 BC, the Japanese archipelago remained isolated from the outside world. During this period, there were few large-scale immigrants from the outside world, except for the indigenous people of the archipelago.

However, among the current Japanese population, people with East Asian and Northeast Asian ancestry account for more than 80% of the total population. This shows that the Japanese archipelago has undergone a very long process of immigration and racial integration.

There is a lot of evidence that after the Yayoi period, a large number of immigrants entered the Japanese archipelago. For example, rice cultivation was brought in by immigrants from China, and the characteristic buildings of the Kofun period in Japan, "Kofun", have also been found on the Korean Peninsula, indicating that immigrants from the Korean Peninsula may have entered Japan as well.

In order to understand how the Japanese population acquired its genetic ancestry and clarify the origins of immigrants, researchers proposed two hypotheses: the "two-source theory" and the "three-source theory."

The two-source theory holds that the current Japanese population is a mixture of aborigines and immigrants from a single source. The three-source theory holds that there are two main sources of immigrants, who migrated to Japan during the Yayoi period and the Kofun period.

To investigate which model was more appropriate, the researchers analyzed the complete nuclear genome of an individual from the Toigahama site, an archaeological site of a Yayoi period cemetery in Yamaguchi Prefecture, Japan.

The researchers found that the genome of this Yayoi period individual had great similarities with the genome of individuals from the later Kofun period, and both had significant genetic similarities with the current population of the Korean Peninsula.

This suggests that between the Yayoi and Kofun periods, immigrants to the Japanese archipelago came mainly from the Korean Peninsula.

The researchers say their next goal is to examine more Yayoi genomes to clarify why more than 80 percent of the genome composition of the modern Japanese population comes from immigrants rather than indigenous Japanese.

The research results were recently published in the Journal of Human Genetics.

The protagonist of this experiment - an ancient human remains from the Yayoi period in Japan. Image source: Jonghyun Kim, Fuzuki Mizuno, Takayuki Matsushita, Masami Matsushita, Saki Aoto, Koji Ishiya, Mami Kamio, Izumi Naka, Michiko Hayashi, Kunihiko Kurosaki, Shintaroh Ueda & Jun Ohashi. Genetic analysis of a Yayoi individual from the Doigahama site provides insights into the origins of immigrants to the Japanese Archipelago. Journal of Human Genetics, 2024 DOI: 10.1038/s10038-024-01295-w

Carrot breeding: equip carrots with a “Chinese core”!

my country is the world's largest carrot producer, but hybrid seeds used in large-scale planting have long relied on imports. The importance of seeds is like the chips of electronic products. In order to achieve independence, we urgently need to forge a strong and hot "Chinese core" for carrots...

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