來源：媒體捲動
編譯｜李言
Science, 6 SEP 2024, Volume 385 Issue 6713
【科學】2024年9月6日，第385卷，6713期
物理學Physics
Achieving optical transparency in live animals with absorbing molecules
透過吸收分子實作活體動物的光學透明
▲ 作者：ZIHAO OU, YI-SHIOU DUH et al.
▲ 連結：https://www.science.org/doi/10.1126/science.adm6869
▲ 摘要：在此。我們報告一反直覺的觀察，即強吸收分子可以在活體動物中實作光學透明。我們探索了這一觀察背後的物理原理，發現當強吸收分子溶解在水中時，它們可以透過Kramers-Kronig關系改變水介質的折射率，以匹配高折射率組織成分（如脂類）的折射率。
我們已經證明，我們的直接方法可以可逆地使活體小鼠身體透明，從而使大範圍的深層結構和活動變得視覺化。這項研究表明，尋找高效能光學清除劑應該集中在強吸收分子上。
▲ Abstract：We report the counterintuitive observation that strongly absorbing molecules can achieve optical transparency in live animals. We explored the physics behind this observation and found that when strongly absorbing molecules dissolve in water, they can modify the refractive index of the aqueous medium through the Kramers-Kronig relations to match that of high-index tissue components such as lipids. We have demonstrated that our straightforward approach can reversibly render a live mouse body transparent to allow visualization of a wide range of deep-seated structures and activities. This work suggests that the search for high-performance optical clearing agents should focus on strongly absorbing molecules.
Phantom energy in the nonlinear response of a quantum many-body scar state
量子多體疤痕態非線性響應中的幽靈能量
▲ 作者：KANGNING YANG, YICHENG ZHANG et al.
▲ 連結：https://www.science.org/doi/10.1126/science.adk8978
▲摘要：在這項研究中，我們使用具有吸引交互作用的鏑瓦斯來制造疤痕狀態，這些狀態足夠穩定，可以在保持其特性的同時被驅動到強非線性狀態。我們測量了淬滅約束勢後，動能和總能量的變化。
盡管裸交互作用是有吸重力的，但原子的行為似乎是相互排斥的：它們的動能隨著瓦斯被壓縮而反常地減少。缺失的「幽靈」能量是透過將我們的實驗結果與廣義流體力學計算相比較來進行基準測試。我們提供的證據表明，缺失的動能是由未被檢測到的高動量原子攜帶的。
▲ Abstract：In this study, we used attractively interacting dysprosium gases to create scar states that are stable enough to be driven into a strongly nonlinear regime while retaining their character. We measured how the kinetic and total energies evolve after quenching the confining potential. Although the bare interactions are attractive, the atoms behave as if they repel each other: Their kinetic energy paradoxically decreases as the gas is compressed. The missing 「phantom」 energy is quantified by benchmarking our experimental results against generalized hydrodynamics calculations. We present evidence that the missing kinetic energy is carried by undetected, very high momentum atoms.
天文學Astronomy
Returned samples indicate volcanism on the Moon 120 million years ago
帶回的樣本表明1.2億年前月球上有火山活動
▲ 作者：BI-WEN WANG, QIAN W. L. ZHANG et al.
▲ 連結：https://www.science.org/doi/10.1126/science.adk6635
▲摘要：我們研究了嫦娥五號收集的月球土壤樣品中的約3000個玻璃珠，並根據它們的質地、化學成分和硫同位素確定了其中3個發源於火山活動。3個火山玻璃珠的鈾鉛測年表明它們形成於1.2（±0.15）億年前。這些火山玻璃珠中稀土元素和釷元素的豐度較高，表明這種近代火山活動可能與巖漿地幔源局部富集生熱元素有關。
▲ Abstract：We investigated ~3000 glass beads in lunar soil samples collected by the Chang’e-5 mission and identified three as having a volcanic origin on the basis of their textures, chemical compositions, and sulfur isotopes. Uranium-lead dating of the three volcanic glass beads shows that they formed 123 ± 15 million years ago. We measured high abundances of rare earth elements and thorium in these volcanic glass beads, which could indicate that such recent volcanism was related to local enrichment of heat-generating elements in the mantle sources of the magma.
地球科學Earth Science
The economic impacts of ecosystem disruptions: Costs from substituting biological pest control
生態系被破壞的經濟影響:替代生物蟲害防治的成本
▲ 作者：EYAL G. FRANK
▲ 連結：https://www.science.org/doi/10.1126/science.adg0344
▲摘要：生物多樣性損失正在加速，但我們對這些生態系的破壞如何影響人類福祉知之甚少。生態學家記錄了蝙蝠作為昆蟲的天然捕食者的重要性，以及在野生動物疾病出現後它們的數量減少，導致生物害蟲控制的潛在下降。
在這項工作中，我研究物種交互作用如何延伸到生態系之外，並影響農業和人類健康。我發現農民透過增加31.1%的殺蟲劑使用量來補償蝙蝠數量的減少。殺蟲劑的補償性增加對健康產生了不利影響——在發生蝙蝠死亡的地區，嬰兒死亡率上升了7.9%。這些發現為之前關於生態系破壞如何產生有意義的社會成本的理論預測提供了驗證。
▲ Abstract：Biodiversity loss is accelerating, yet we know little about how these ecosystem disruptions affect human well-being. Ecologists have documented both the importance of bats as natural predators of insects as well as their population declines after the emergence of a wildlife disease, resulting in a potential decline in biological pest control. In this work, I study how species interactions can extend beyond an ecosystem and affect agriculture and human health. I find that farmers compensated for bat decline by increasing their insecticide use by 31.1%. The compensatory increase in insecticide use by farmers adversely affected health—human infant mortality increased by 7.9% in the counties that experienced bat die-offs. These findings provide empirical validation to previous theoretical predictions about how ecosystem disruptions can have meaningful social costs.
動物學Zoology
Spatial cognitive ability is associated with longevity in food-caching chickadees
儲存食物的山雀的壽命與空間認知能力有關
▲ 作者：JOSEPH F. WELKLIN, BENJAMIN R. SONNENBERG et al.
▲ 連結：https://www.science.org/doi/10.1126/science.adn5633
▲摘要：我們提出的直接證據表明，個體認知能力的差異與貯藏食物的野生鳥類的壽命差異相關。我們測量了227只山雀的空間認知能力，並跟蹤了它們在自然環境中的壽命，發現具有更好的空間學習和記憶能力的個體壽命更長。這些結果證實，增強的認知能力可能與野生動物的壽命長度有關，並且增強認知能力可能導致壽命延長。
▲ Abstract：We present direct evidence that individual variation in cognitive abilities is associated with differences in life span in a wild food caching bird. We measured the spatial cognitive abilities and tracked the life span of 227 mountain chickadees (Poecile gambeli) in their natural environment and found that individuals with better spatial learning and memory abilities involved in food caching lived longer. These results confirm that enhanced cognitive abilities can be associated with longer life in wild animals and that selection on cognitive abilities can lead to increased life span.
生物學Biology
Organizing the coactivity structure of the hippocampus from robust to flexible memory
組織海馬體從穩健記憶到靈活記憶的協同活動結構
▲ 作者：GIUSEPPE P. GAVA, LAURA LEFèVRE et al.
▲ 連結：https://www.science.org/doi/10.1126/science.adk9611
▲ 摘要：在此，我們報告獲得穩健（食物環境）記憶限制了小鼠海馬在高度相關的峰值序列的群體活動空間內，從而阻止了隨後靈活（物體定位）記憶的計算。這種緊密相關的結構是在重復的助記經驗中形成的，逐漸將CA1層金字塔狀淺層的神經元與整個群體的活動耦合起來。
套用海馬體θ驅動的閉環光遺傳抑制來減輕（食物—環境）記憶形成過程中的神經元募集，放松了海馬體協同活動的拓撲限制，並恢復了隨後的靈活（物體定位）記憶。
▲ Abstract：We report that acquiring a robust (food-context) memory constrains the mouse hippocampus within a population activity space of highly correlated spike trains that prevents subsequent computation of a flexible (object-location) memory. This densely correlated firing structure developed over repeated mnemonic experience, gradually coupling neurons in the superficial sublayer of the CA1 stratum pyramidale to whole-population activity. Applying hippocampal theta-driven closed-loop optogenetic suppression to mitigate this neuronal recruitment during (food-context) memory formation relaxed the topological constraint on hippocampal coactivity and restored subsequent flexible (object-location) memory.
