《科学》(20221104出版)一周论文导读

编译 | 冯维维

Science, 4 November 2022, Volume 378 Issue 6619

《科学》2022年11月4日,第378卷6619期


物理学Physics


Evidence for neutrino emission from the nearby active galaxy NGC 1068

来自附近活动星系NGC 1068的中微子发射证据

▲ 作者:ICECUBE COLLABORATION, R. ABBASIM. ACKERMANNJ. ADAMSJ. A. AGUILARM. AHLERSM. AHRENSJ. M. ALAMEDDINEC. ALISPACH, P. ZHELNIN Authors Info & Affiliations, etc.

▲ 链接:

https://www.science.org/doi/10.1126/science.abg3395

▲ 摘要:

科学观测证明了高能中微子的弥散背景,它们已被确认于河外起源。但很难确定造成这一背景的个别来源。“冰立方”合作项目重新分析了天体物理中微子的到达方向,然后寻找点源。

他们从附近的活动星系NGC 1068(即Messier 77)中发现了中微子发射的证据。它的性质与2018年发现的中微子源TXS 0506+056有很大不同,这使得研究人员认为,可能有不止一个种群对中微子背景做出了贡献。

▲ Abstract:

Observations have shown a diffuse background of high-energy neutrinos, which is known to be of extragalactic origin. However, it has been difficult to identify inpidual sources that contribute to this background. The IceCube Collaboration reanalyzed the arrival directions of astrophysical neutrinos and then searched for point sources. They identified evidence for neutrino emission from NGC 1068 (also known as Messier 77), a nearby active galaxy. Its properties are quite different from TXS 0506+056, which was found to be a neutrino source in 2018, leading the investigators to suggest that there might be more than one population contributing to the neutrino background.


Robust multi-qubit quantum network node with integrated error detection

具有集成错误检测性能的鲁棒多量子比特量子网络节点

▲ 作者:P. -J. STAS, Y. Q. HUAN, B. MACHIELSE, E. N. KNALL, A. SULEYMANZADE, B. PINGAULTM. SUTULA, S. W. DING, C. M. KNAUT, M. D. LUKIN, etc

▲ 链接:

https://www.science.org/doi/10.1126/science.add9771

▲ 摘要:

开发量子网络和长距离通信量子信息的能力需要具有高效光接口和长存储时间的量子存储节点。金刚石色中心具有较长的相干时间和高效的光学界面,是实现这一目标的理想材料。作者利用金刚石中的硅空位,并将这些特性集成到单个器件中。

他们演示了种寿命超过2秒的量子存储器和双量子位寄存器量子态的全光学控制。该平台具有内置的错误检测能力,为可扩展量子网络的发展提供了广阔的前景。

▲ Abstract:

The ability to develop quantum networks and communicate quantum information over long distances requires quantum memory nodes with efficient optical interfaces and long memory times. Because of their long coherence times and efficient optical interface, color centers in diamond are promising candidates to achieve this goal. Stas et al. use silicon vacancies in diamond and integrated the properties into a single device (see the Perspective by Gangloff). The authors demonstrate a quantum memory with a lifetime exceeding 2 seconds and full optical control of the quantum states of the two-qubit register. With the capability of built-in error detection, such a platform is promising for the development of scalable quantum networks. —


气候Climate


Unprecedented fire activity above the Arctic Circle linked to rising temperatures

北极圈上空前所未有的火灾活动与气温上升有关

作者:ADRIÀ DESCALS, DAVID L. A. GAVEAU, ALEIXANDRE VERGER, DOUGLAS SHEIL, DAISUKE NAITO, AND JOSEP PE?UELAS

▲ 链接:

https://www.science.org/doi/10.1126/science.abn9768

▲ 摘要:

北极的火灾可以从永久冻土泥炭地释放出大量的碳。卫星观测显示,2019年和2020年大火烧毁了约470万公顷泥炭地,占整个1982-2020年期间西伯利亚北极地区烧毁总面积的44%。

2020年的夏天是四十年来最温暖的夏天,大火烧毁了前所未有的大面积富含碳的土壤。研究表明,近几十年来与温度相关的火灾因素有所增加,并确定了这些因素与年燃烧面积之间的近指数关系。

在本世纪中叶之前,随着气候变暖,北极的大火可能会再次发生,因为温度趋势正在达到一个阈值,即温度的小幅上升与燃烧面积的指数增长相关。

▲ Abstract:

Arctic fires can release large amounts of carbon from permafrost peatlands. Satellite observations reveal that fires burned ~4.7 million hectares in 2019 and 2020, accounting for 44% of the total burned area in the Siberian Arctic for the entire 1982–2020 period. The summer of 2020 was the warmest in four decades, with fires burning an unprecedentedly large area of carbon-rich soils. We show that factors of fire associated with temperature have increased in recent decades and identified a near-exponential relationship between these factors and annual burned area. Large fires in the Arctic are likely to recur with climatic warming before mid-century, because the temperature trend is reaching a threshold in which small increases in temperature are associated with exponential increases in the area burned.


The January 2022 eruption of Hunga Tonga-Hunga Ha’apai volcano reached the mesosphere

汤加火山喷发物质到达中间层

▲ 作者:SIMON R. PROUD, ANDREW T. PRATA, AND SIMEON SCHMAUS

▲ 链接:

https://www.science.org/doi/10.1126/science.abo4076

▲ 摘要:

大规模、爆炸性的火山爆发可以将火山灰、气体和水等物质抛入平流层,对大气成分和气候产生可测量的影响。作者使用了2022年1月汤加火山喷发的地球同步卫星图像,这是有记录以来最大的喷发之一,显示其火山云达到了57公里的高度,远远超过平流层,进入中间层,高于之前记录的任何火山羽流。这是第一次看到羽流穿透平流层顶。

▲ Abstract:

Large, explosive volcanic eruptions can loft material such as ash, gases, and water all the way into the stratosphere, with measurable impacts on atmospheric composition and climate. Proud et al. used geostationary satellite images of the January 2022 Hunga-Tonga volcano eruption, one of the largest eruptions ever recorded, to show that its volcanic cloud reached an altitude of 57 kilometers, well past the stratosphere and into the mesosphere and higher than any volcanic plume previously recorded. This is the first time a plume has been seen to penetrate the stratopause.


生命科学Life Science


On-demand cell-autonomous gene therapy for brain circuit disorders

细胞自主基因按需治疗脑回路紊乱

▲ 作者:YICHEN QIU, NATHANAEL O’NEILL, BENITO MAFFEICLARA ZOURRAY, AMANDA ALMACELLAS-BARBANOJ, JENNA C. CARPENTER, GABRIELE LIGNANI, etc.

▲ 链接:

https://www.science.org/doi/10.1126/science.abq6656

▲ 摘要:

近三分之一的癫痫患者对目前可用的抗癫痫药物没有反应。科学家已经提出了几种基因治疗方法,但这些方法往往不加区别地针对特定大脑区域的所有神经元。

作者开发了一种基因治疗策略,可以自我选择在病理上过度活跃的神经元,并在闭环中下调它们的兴奋性。他们将编码钾通道的KCNA1基因置于一种即时早期基因启动子的控制之下,该启动子的活性由强烈的神经元放电启动。

一旦大脑回路活动恢复到基线水平,治疗就会自动关闭。这种方法原则上可以用于治疗任何神经精神障碍,其中只有一个神经元亚群在病理上过度活跃。

▲ Abstract:

Nearly one-third of epilepsy patients do not respond to currently available anti-epileptic drugs. Several gene therapy approaches have been suggested, but these methods tend to indiscriminately target all neurons in a given brain region. Qiu et al. developed a gene therapy strategy that self-selects neurons that are pathologically overactive and down-regulates their excitability in a closed loop. They put the KCNA1 gene, which encodes a potassium channel, under the control of an immediate early gene promoter with activity that is switched on by intense neuronal firing. The treatment switches itself off once brain circuit activity has returned to baseline. This approach could in principle be used to treat any neuropsychiatric disorder in which only a subpopulation of neurons is pathologically overactive.


The control of carpel determinacy pathway leads to sex determination in cucurbits

心皮决定通路的控制决定瓜类性别选择

▲ 作者:SIQI ZHANG, FENG-QUAN TAN, XCHING-HUI CHUNGFILIP SLAVKOVICRAVI SURESHBHAI DEVANI, CHRISTELLE TROADEC, FABIEN MARCEL, HALIMA MORINC?LINE CAMPS, ABDELHAFID

▲ 链接:

https://www.science.org/doi/10.1126/science.add4250

▲ 摘要:

在瓜类中,花最初是双性性发育的,但进一步的发育导致心皮或雄蕊发育的停滞,使成熟的花细化为雄性或雌性。只有雌花才会出瓜。Zhang等人已经确定了参与两性原始花变成雄性或雌性花的基因。锌指转录因子WIP1会干扰心皮的发育,使雄花得以继续发育。相反,一种与产生激素乙烯有关的酶的表达,可能是由生长素信号支持的,支持和促进雌花的发育。

研究结果表明,性别基因的进化干扰了花的分生功能,导致了单性花的发育。

▲ Abstract:

In melons, flowers initially develop bisexually, but further development brings arrest of either carpel or stamen development, refining mature flowers into male or female. Only the female flowers produce melons. Zhang et al. have identified the genes involved in turning the bisexual primordial flower into either a male or female flower. The zinc finger transcription factor WIP1 interferes with carpel development, allowing male flower development to proceed. Conversely, expression of an enzyme involved in producing the hormone ethylene, perhaps supported by auxin signaling, supports and promotes female flower development. The findings suggest that sex genes evolved to interfere with flower meristematic function, leading to unisexual flower development.

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