生命科学Life Science Engineered deletions of HIV replicate conditionally to reduce disease in nonhuman primates 在非人类灵长类动物中，有前提地复制艾滋病病毒基因工程缺掉以削减疾病 ▲ 作者：FATHIMA N. NAGOOR PITCHAI, ELIZABETH J. TANNER, NEHA KHETAN, GUSTAVO VASEN, CLARA LEVREL, ARJUN J. KUMAR, SHILPI PANDEY, TRACY ORDONEZ, PHILIP BARNETTE, AND LEOR S. WEINBERGER ▲链接： https://www.science.org/doi/10.1126/science.adn5866 ▲摘要： 在复制进程中，RNA病毒常常发生出缺陷的颗粒，这些颗粒寄生并干扰完全病毒的复制和包装。这些出缺陷的颗粒也可能刺激宿主的免疫反映。Pitchai等人开辟了一种持续培育方式，此中将缺掉克隆到艾滋病病毒（HIV）中以发生医治性干扰粒子（TIPs）。 起首，他们发现具有转导能力的病毒样颗粒是有前提地在完全的HIV和削减的HIV载量的转运中发生的。测序没有检测到随后的年夜缺掉或重排。然后在捐赠的HIV传染的人类细胞、人源化小鼠和传染HIV的非人灵长类动物中打针一剂量的工程化TIPS进行测试。这些尝试证实了血清转化、按捺HIV复制和TIP延续最少30周。 ▲ Abstract： During replication, RNA viruses frequently generate defective particles that parasitize and interfere with the replication and packaging of intact virus. Such defective particles may also stimulate host immune responses. Pitchai et al. developed a continuous culture method in which deletions were cloned into HIV to generate therapeutic interfering particles (TIPs). First, they showed that transduction-competent viral-like particles were produced conditionally in trans with intact HIV and reduced HIV load. Sequencing did not detect subsequent large deletions or rearrangements. Engineered TIPS were then tested with one injected dose in donated HIV-infected human cells, humanized mice, and nonhuman primates infected with HIV. These experiments verified seroconversion, suppression of HIV replication, and TIP persistence for at least 30 weeks. Brain region specific action of ketamine as a rapid antidepressant 氯胺酮作为快速抗抑郁药的脑区域特异性感化 ▲ 作者：MIN CHEN, SHUANGSHUANG MA, HANXIAO LIU, YIYAN DONG, JINGXIANG TANG, ZHEYI NI, YI TAN, CHENCHI DUAN, HUI LI, AND HAILAN HU ▲链接： https://www.science.org/doi/10.1126/science.ado7010 ▲摘要： 氯胺酮抗抑郁感化的发现是心理健康医治的主要进展。但是，其潜伏机制仍未完全领会。Chen等人发现，在近似抑郁的动物中，氯胺酮选择性地按捺了侧缰核神经元的NMDA受体反映，但对海马锥体神经元没有感化。 研究者发现，与海马神经元比拟，侧缰核神经元在抑郁状况下具有更高的内涵活性，而且突触外的NMDA受体库要小很多。经由过程增添海马神经元的内涵活性或下降外侧缰核神经元的活性，可以互换NMDA受体对氯胺酮阻断反映的敏感性。去除侧缰中强迫性NMDA受体亚基NR1可禁止氯胺酮的抗抑郁感化。 ▲ Abstract： The discovery of the antidepressant effects of ketamine is an important advance in mental health therapy. However, the underlying mechanisms are still not fully understood. Chen et al. found that in depressive-like animals, ketamine selectively inhibited NMDA receptor responses in lateral habenula neurons, but not in hippocampal pyramidal neurons. Compared with hippocampal neurons, lateral habenula neurons have much higher intrinsic activity in the depressive state and a much smaller extrasynaptic reservoir pool of NMDA receptors. By increasing the intrinsic activity of hippocampal neurons or decreasing the activity of lateral habenula neurons, the sensitivity of their NMDA receptor responses to ketamine blockade雷竞技 could be swapped. Removal of the obligatory NMDA receptor subunit NR1 in the lateral habenula prevented ketamine s antidepressant effects. 物理学Physics High-temperature quantum valley Hall effect with quantized resistance and a topological switch 具有量子化电阻和拓扑开关的高温量子谷霍尔效应 ▲ 作者：KE HUANG, HAILONG FU, KENJI WATANABE, TAKASHI TANIGUCHI, AND JUN ZHU ▲链接： https://www.science.org/doi/10.1126/science.adj3742 ▲摘要： 在某些环境下，拓扑固态器件中的电子活动能以近似量子光学的体例进行节制。这个概念的焦点是拓扑边沿状况，抱负环境下，它应当没有后向散射，也不需要外加磁场。Huang等人不雅察到，在零磁场下，双层石墨烯中的一种称为扭结态的螺旋边沿态与电阻的很是切确的量化有关。 当温度增添到50K摆布时，量子化仅表示出稍微的恶化，注解对后向散射的庇护。研究者演示了拓扑节制开关的电气操作，其通/关比为200。这些成果证实了扭结态的鲁棒性和可调性，和它在构建电子量子光学器件方面的前景。 ▲ Abstract： The motion of electrons in topological solid-state devices can be controlled in a manner analogous to quantum optics under certain circumstances. Central to this concept are topological edge states, which ideally should exhibit no backscattering and should not require an applied magnetic field. Huang et al. observed a very precise quantization of resistance associated with a type of helical edge states called kink states in bilayer graphene at zero magnetic field. The quantization exhibited only a slight deterioration as the temperature was increased to about 50 K, indicating protection against backscattering. Toward liquid cell quantum sensing: Ytterbium complexes with ultranarrow absorption 液体电池量子传感：具有超窄接收的镱化合物 ▲ 作者：ASHLEY J. SHIN, CHANGLING ZHAO, YI SHEN, CLAIRE E. DICKERSON, BARRY LI, HOOTAN ROSHANDEL, DANIEL B M, TIMOTHY L. ATALLAH, PAUL H. OYALA, AND JUSTIN R. CARAM ▲链接： https://www.science.org/doi/10.1126/science.adf7577 ▲摘要： 蒸汽电池中的碱原子调集是检测电磁场最通用的系统之一，并用在制造最活络的磁力计。但是，这类原子蒸汽电池的低密度限制了它们的活络度。Shin等人提出了一种液体摹拟物，可以供给更高的密度数和更高的化学可调性，从而有可能降服该手艺的局限性。 作者报导了一种二茂铁负载的镱共同物，在室温下在溶液中表示出超窄的接收线宽。该研究展现了定制份子在基在液体的切确量子传感中的潜力，这将有助在将来利用。 ▲ Abstract： Alkali atom ensembles in vapor cells are among the most versatile systems for detecting electromagnetic fields and are used to manufacture the most sensitive magnetometers. However, low number densities in such atomic vapor cells limit their sensitivity. Shin et al. proposed a liquid analog that can offer higher density numbers and higher chemical tunability, thus potentially overcoming the limitations of this technology. The authors reported a ferrocene-supported ytterbium complex that exhibits an ultranarrow absorption linewidth in solution at room temperature. Their work showcases the potential of tailor-designed molecules in liquid-based precision quantum sensing, which may spark future applications. 地质学和材料学 Geology Materials Science A long section of serpentinized depleted mantle peridotite 一长段蛇纹石化的枯竭地幔橄榄岩 ▲ 作者：C. JOHAN LISSENBERG, ANDREW M. MCCAIG, SUSAN Q. LANG, PETER BLUM, NATSUE ABE, WILLIAM J. BRAZELTON, R MI COLTAT, JEREMY R. DEANS, KRISTIN L. DICKERSON, AND SARAH TREADWELL ▲链接： https://www.science.org/doi/10.1126/science.adp1058 ▲摘要： 地球的地幔很难取样，其年夜部门直接信息来自从海底挖出的岩石，或来自以蛇绿岩的情势被推到地壳上的古代地幔。Lissenberg等人展现了国际海洋钻探项目远征399的船上不雅测成果，该项目在海底地幔下钻了1268米深。 岩石剖面是从年夜西洋中脊四周的热液活跃区恢复的，应当有助在我们更好地舆解地幔岩石的化学成份，这些岩石是由四周岩浆提取进程构成的，构成了新的海洋地壳。 ▲ Abstract： The mantle of the Earth is hard to sample, with most of our direct information about it coming from rocks dredged off the ocean floor or from ancient mantle thrust up onto the crust in the form of ophiolites. Lissenberg et al. present the shipboard observations from the International Ocean Drilling Project Expedition 399, which drilled 1268 meters deep into the mantle under the seafloor. The rock section was recovered from a hydrothermally active region near the mid-Atlantic ridge and should help us better understand the chemistry of mantle rocks shaped by the nearby magma extraction process that forms new ocean crust. Strengthening gold with dispersed nanovoids 分离纳米孔洞强化金 ▲ 作者：JIA-JI CHEN, HUI XIE, LING-ZHI LIU, HUAI GUAN, ZESHENG YOU, LIJIE ZOU, AND HAI-JUN JIN ▲链接： https://www.science.org/doi/10.1126/science.abo7579 ▲摘要： 材料在含有空地的环境下，常常在载荷感化下过早或灾害性地掉效，这对材料制造提出了挑战。Chen等人发现，当孔洞缩小到亚微米或纳米标准时，含有高达10%球形孔洞的金不会在张力下过早断裂。相反，分离的纳米空地增添了材料的强度和延展性，同时减轻了材料的重量。 除按捺应力或应变集中外，这类布局供给了庞大的概况积，增进了概况位错的彼此感化，从而实现了强化和额外的应变硬化，从而实现了增韧。将近似裂纹的有害缺点中的浮泛转化为有益的 成份 ，为开辟新型轻质高机能材料供给了一种便宜且环保的方式。 ▲ Abstract： Materials often fail prematurely or catastrophically under load while containing voids, posing a challenge to materials manufacturing. We found that a metal (gold) containing spherical voids with a fraction of up to 10% does not fracture prematurely in tension when the voids are shrunk to the submicron or nanometer scale. Instead, the dispersed nanovoids increase the strength and ductility of the material while simultaneously reducing its weight. Apart from the suppressed stress or strain concentration, such structure provides enormous surface area and promotes surface-dislocation interactions, which enable strengthening and additional strain hardening and thus toughening. Transforming voids from crack-like detrimental defects into a beneficial ingredient provides an inexpensive and environmentally friendly approach for the development of a new class of lightweight, high-performance materials.特殊声明：本文转载仅仅是出在传布信息的需要，其实不意味着代表本网站不雅点或证实其内容的真实性；如其他媒体、网站或小我从本网站转载利用，须保存本网站注明的“来历”，并自大版权等法令责任；作者假如不但愿被转载或联系转载稿费等事宜，请与我们联系。
