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科學美國人:有些驅蚊劑就像隱形斗篷一樣

zlxxm 于2019-12-31發布 l 已有人瀏覽
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“所以這些以前會強烈激活嗅覺系統的氣味現在基本上沒有任何作用?!幣饉際喬眉?,比如避蚊胺,實際上就像對付蚊子的隱形斗篷。詳情發表在《當代生物學》雜志上。
    小E英語歡迎您,請點擊播放按鈕開始播放……

体育比分预测竞猜网站 www.010514.live Some Mosquito Repellents Act Like Invisibility Cloaks

有些驅蚊劑就像隱形斗篷一樣

It might seem obvious that the primary function of insect repellents like DEET is to, well, repel. But if you bring a pipette tip full of DEET right up to a mosquito, as Johns Hopkins neuroscientist Chris Potter did, "she just ignores it. So that really does demonstrate that DEET by itself is not repellent, and it's not going to make them fly away."

似乎很明顯,驅蚊劑,比如避蚊胺的主要功能是驅蚊。但如果你像約翰霍普金斯大學的神經學家克里斯·波特那樣,把一根裝滿避蚊胺的吸管直接拿去碰蚊子,“根本沒用。”所以這確實證明了避蚊胺本身并不存在驅蚊作用,也無法驅散蚊子。”

Potter's team also genetically engineered Anopheles mosquitoes to make their antennae light up when their olfactory neurons picked up on a scent. But when they spritzed the antennae with DEET and other so-called "repellents," even at 100 percent strength, "There just was no response.""So that was a surprise to us. Going into this we thought, ok they're insect repellents, they're going to activate neurons, that's how they repel mosquitoes. So then the question is, what are they actually doing?"

波特的研究小組還對按蚊進行了基因改造,使它們在嗅到氣味時,其嗅覺神經元的觸須會發光。但是當他們用驅蚊胺和其他所謂的“驅蚊劑”噴灑觸須時,即使是100%的強度,“也沒有反應。”“所以我們對此很是震驚。我們認為,這是驅蟲劑,它們會激活神經元,這就是它們驅蚊的方式。那么問題來了,它們的作用到底是什么?”

The researchers kept experimenting with those genetically modified mosquitoes to find out. A whiff of molecules commonly found on human skin made the mosquitoes' antennae light up like a Christmas tree, Potter says. So they do sense us... which you've likely experienced. But when they combined compounds from our natural human perfume with DEET and other synthetic repellents... the antennae just flickered dimly.

為了找到答案,研究人員一直在對這些轉基因蚊子進行實驗。一種常見于人類皮膚上的分子氣味使蚊子的觸角像圣誕樹一樣亮了起來,波特說道。所以蚊子確實能感覺到人類......你可能也經歷過。但是,當他們將人類天然香水中的化合物與避蚊胺和其他合成驅蚊劑混合在一起時,觸角就微弱閃爍。

So these odors which before would strongly activate the olfactory system essentially now didn't do anything. Meaning repellents like DEET actually act like an invisibility cloak against mosquitoes. The details are in the journal Current Biology.

“所以這些以前會強烈激活嗅覺系統的氣味現在基本上沒有任何作用。”意思是驅蚊劑,比如避蚊胺,實際上就像對付蚊子的隱形斗篷。詳情發表在《當代生物學》雜志上。

Natural repellents on the other hand, like lemongrass oil, strongly activated the skeeter's senses... in a negative way. And they weren't as affected by masking chemicals like DEET. So the scientists say maybe you could combine them - to both offend the mosquitoes' senses and to mask the more irresistible scent... of you.

另一方面,天然的驅蟲劑,比如檸檬草油,強烈地激活了蚊子的感官......以一種不理想的方式。它們不會受到像避蚊胺這樣的化學物質的影響。因此,科學家們建議也許可以把二者結合起來——既能刺激蚊子的感官,又能在身上留下更誘人的氣味。

- Christopher Intagliata

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