科研
科研
编译 | 李言
Science, 8 Nov 2024, Volume 386 Issue 6722
《科学》2024年11月8日，第386卷，6722期
材料科学Materials Science
Janus channel of membranes enables concurrent oil and water recovery from emulsions
“两面神”膜从乳液中同时回收油和水
▲ 作者：Xin-Yu Guo, Lei Zhao et al.
▲链接：
https://www.science.org/doi/10.1126/science.adq6329
▲摘要：
我们提出了一种“两面神”膜通道（JCM），其特点是由一对亲水性和疏水性膜构成的封闭结构。这种材料可以同时从表面活性剂稳定的乳液中高效地回收油和水。
受限的“两面神”膜可以通过一个包括富集和破乳的反馈回路放大膜对的相互作用。我们的JCM的油和水回收率分别高达97%和75%，纯度接近99.9%。
此外，它在处理各种乳剂方面的通用性可以使一系列分离的液体排放接近于零。
▲ Abstract：
We present a Janus channel of membranes (JCM) that features a confined architecture constructed of a pair of hydrophilic and hydrophobic membranes, which allows for concurrent, highly efficient recovery of oil and water from surfactant-stabilized emulsions. The confined Janus channel can amplify the interplay of the membrane pair through a feedback loop that involves enrichment and demulsification. Our JCM achieves exceptional oil and water recoveries of up to 97 and 75%, respectively, with near 99.9% purities. Moreover, its versatility in handling diverse emulsions may enable near-zero liquid discharge for a range of separations.
Ultrahigh–surface area covalent organic frameworks for methane adsorption
用于甲烷吸附的超高表面积共价有机框架
▲ 作者：Ying Yin, Ya Zhang et al.
▲链接：
https://www.science.org/doi/10.1126/science.adr0936
▲摘要：
在此，我们报告两种具有罕见的自链alb-3,6-Ccc2拓扑结构和孔径为1.1纳米的三维共价有机框架（COFs）。
值得注意的是，这些亚胺连接的微孔COFs具有高重量的BET比表面积（每克约4400平方米）和体积BET比表面积（每立方厘米约1900平方米）。
此外，在100 bar和298开尔文条件下，它们的体积甲烷吸收量高达264立方厘米（标准温度和压力）/立方厘米[cm3 (STP) cm?3]，在5至100 bar和298开尔文条件下，它们的体积容量最高，为237 cm3 (STP) cm?3。
▲ Abstract：
Here, we report two isostructural three-dimensional covalent organic frameworks (COFs) with a rare self-catenated alb-3,6-Ccc2 topology and a pore size of 1.1 nanometer. Notably, these imine-linked microporous COFs show both high gravimetric Brunauer–Emmett–Teller (BET) surface areas (~4400 square meters per gram) and volumetric BET surface areas (~1900 square meters per cubic centimeter). Moreover, their volumetric methane uptake reaches up to 264 cubic centimeter (standard temperature and pressure) per cubic centimeter [cm3 (STP) cm?3] at 100 bar and 298 kelvin, and they exhibit the highest volumetric working capacity of 237 cm3 (STP) cm?3 at 5 to 100 bar and 298 kelvin among all reported porous crystalline materials.
生物学Biology
C-LTMRs evoke wet dog shakes via the spinoparabrachial pathway
C-LTMRs通过脊髓旁臂通路引起身上湿了的狗抖动
▲ 作者：Dawei Zhang, Josef Turecek, Seungwon Choi et al.
▲链接：
https://www.science.org/doi/10.1126/science.adq8834
▲摘要：
许多多毛哺乳动物会进行身体的快速摆动，称为“湿狗抖水”，以清除背部皮肤上的水分和刺激物。这种行为背后的体感机制尚不明晰。
我们报道了压电依赖的机械感觉介导了水或油滴应用于小鼠背部毛状皮肤引起的“湿狗抖水”。无髓鞘C-纤维低阈值机械感受器（C-LTMRs）被油滴激活，其光遗传学激活引起“湿狗抖水”。C-LTMRs的消融减弱了这种行为。
此外，C-LTMRs与脊髓旁臂神经元突触偶联，光遗传抑制脊髓旁臂神经元突触和臂旁核兴奋性神经元对油滴和C-LTMRs诱发的“湿狗抖水”均有抑制。因此，C-LTMRs脊髓旁臂通路促进湿狗摇动以去除背部毛状皮肤上的水分和机械刺激物。
▲ Abstract：
Many hairy mammals perform rapid oscillations of their body, called wet dog shakes, to remove water and irritants from their back hairy skin. The somatosensory mechanisms that underlie this behavior are unclear. We report that Piezo2-dependent mechanosensation mediates wet dog shakes evoked by water or oil droplets applied to back hairy skin of mice. Unmyelinated C-fiber low-threshold mechanoreceptors (C-LTMRs) were activated by oil droplets, and their optogenetic activation elicited wet dog shakes. Ablation of C-LTMRs attenuated this behavior. Moreover, C-LTMRs synaptically couple to spinoparabrachial neurons, and optogenetically inhibiting spinoparabrachial neuron synapses and excitatory neurons in the parabrachial nucleus impaired both oil droplet– and C-LTMR–evoked wet dog shakes. Thus, a C-LTMR–spinoparabrachial pathway promotes wet dog shakes for removal of water and mechanical irritants from back hairy skin.
A trade-off between investment in molecular defense repertoires and growth in plants
在分子防御库的投资和植物生长之间的权衡
▲ 作者：Michael Giolai and Anna-Liisa Laine
▲链接：
https://www.science.org/doi/10.1126/science.adn2779
▲摘要：
鉴于病原体对宿主的负面适应性效应，抗性的好处应该是普遍的。
然而，在不同的植物物种之间，核苷酸结合的富含亮氨酸的重复受体的数量存在显著差异，这是防御的基石。“增长—防御权衡”假说预测了与防御投资相关的成本，以产生这些特征的变化。
我们将187种植物的细胞内免疫受体库的特征与性状数据进行比较，结果表明，在野生植物中，分子防御库的大小与生长呈负相关。
相比之下，我们没有在农业植物中发现“生长—防御权衡”的证据。我们的跨物种方法强调了防御投资在塑造生态性状变异及其对驯化的敏感性方面的核心作用。
▲ Abstract：
Given the negative fitness effects that pathogens impose on their hosts, the benefits of resistance should be universal. However, there is marked variation across plant species in the number of nucleotide-binding leucine-rich repeat receptors, which form a cornerstone of defense. The growth–defense trade-off hypothesis predicts costs associated with defense investment to generate variation in these traits. Our analysis comparing features of the intracellular immune-receptor repertoires with trait data of 187 species shows that in wild plants, the size of the molecular defense repertoire correlates negatively with growth. By contrast, we do not find evidence for a growth–defense trade-off in agricultural plants. Our cross-species approach highlights the central role of defense investment in shaping ecological trait variation and its sensitivity to domestication.
医学Medicine
Hepatic vagal afferents convey clock-dependent signals to regulate circadian food intake
肝迷走神经传入传递时钟依赖性信号以调节昼夜食物摄入
▲ 作者：Lauren N. Woodie, Lily C. Melink et al.
▲链接：
https://www.science.org/doi/10.1126/science.adn2786
▲摘要：
倒班或时差引起的昼夜节律不同步对代谢健康有害，但是否同步信号是如何在组织间的传递尚不清楚。
我们报道肝脏分子钟功能障碍是通过肝迷走传入神经（HVAN）向大脑发出信号，导致食物摄入模式改变。肝支迷走神经切开术还可以防止高脂肪饮食引起的食物摄入中断，减少体重增加。
我们的研究结果揭示了一种稳态反馈信号，它依赖于肝脏和大脑之间的交流来控制昼夜节律的食物摄入模式。这就确定了肝迷走神经作为一种潜在的治疗肥胖症的目标。
▲ Abstract：
Circadian desynchrony induced by shiftwork or jet lag is detrimental to metabolic health, but how synchronous or desynchronous signals are transmitted among tissues is unknown. We report that liver molecular clock dysfunction is signaled to the brain through the hepatic vagal afferent nerve (HVAN), leading to altered food intake patterns that are corrected by ablation of the HVAN. Hepatic branch vagotomy also prevents food intake disruptions induced by high-fat diet feeding and reduces body weight gain. Our findings reveal a homeostatic feedback signal that relies on communication between the liver and the brain to control circadian food intake patterns. This identifies the hepatic vagus nerve as a potential therapeutic target for obesity in the setting of chronodisruption.
地球科学Earth Science
Revisiting the mid-Pleistocene transition ocean circulation crisis
重新审视中更新世过渡时期的海洋环流危机
▲ 作者：Sophia K. V. Hines, Christopher D. Charles et al.
▲链接：
https://www.science.org/doi/10.1126/science.adn4154
▲摘要：
中更新世过渡（MPT）标志着冰期—间冰期气候特征的转变。关于MPT起源的一个普遍假设是，冰川深海环流发生了根本性的变化，其标志是在约90万年（海洋同位素阶段24至22）发生环流“危机”。
利用来自南大西洋（开普盆地）横跨MPT的高分辨率配对钕、碳和氧同位素数据，我们没有发现深海环流发生实质性变化的证据。
在MPT早期（约130万至112万年）之前和期间，冰川深海变率与最近一次冰旋回非常相似。通过在MPT上发展深海分层促进的碳储存只需要适度的环流调整。
▲ Abstract：
The mid-Pleistocene transition (MPT) [~1.25 to 0.85 million years ago (Ma)] marks a shift in the character of glacial-interglacial climate. One prevailing hypothesis for the origin of the MPT is that glacial deep ocean circulation fundamentally changed, marked by a circulation “crisis” at ~0.90 Ma (marine isotope stages 24 to 22). Using high-resolution paired neodymium, carbon, and oxygen isotope data from the South Atlantic Ocean (Cape Basin) across the MPT, we find no evidence of a substantial change in deep ocean circulation. Before and during the early MPT (~1.30 to 1.12 Ma), the glacial deep ocean variability closely resembled that of the most recent glacial cycle. The carbon storage facilitated by developing deep ocean stratification across the MPT required only modest circulation adjustments.
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