化学Chemistry Growth of complete ammonia oxidizers on guanidine 完全氨氧化剂在胍上的发展 ▲ 作者：Marton Palatinszky, Craig W. Herbold et al. ▲链接： https://www.nature.com/articles/s41586-024-07832-z ▲摘要： 在此，我们证实了完全氨氧化剂硝化螺旋菌和年夜大都其他comammox微生物可以以胍为独一的能量、还原剂和氮源发展。卵白质组学、酶动力学和晶体布局的研究注解，它是一种真实的胍酶。含comammox的农业泥土和污水处置厂微生物组的培育尝试注解，胍是情况中硝化感化的底物。胍作为comammox发展底物的判定显示了这些全球主要硝化菌的出乎料想的生态位，并为它们的分手供给了机遇。 ▲ Abstract： Here we show that the complete ammonia oxidizer (comammox) Nitrospira inopinata and probably most other comammox microorganisms can grow on guanidine as the sole source of energy, reductant and nitrogen. Proteomics, enzyme kinetics and the crystal structure of a N. inopinata guanidinase homologue demonstrated that it is a bona fide guanidinase. Incubation experiments with comammox-containing agricultural soil and wastewater treatment plant microbiomes suggested that guanidine serves as substrate for nitrification in the environment. The identification of guanidine as a growth substrate for comammox shows an unexpected niche of these globally important nitrifiers and offers opportunities for their isolation. 物理学Physics Dynamic transition and Galilean relativity of current-driven skyrmions 电流驱动斯格明子的动态跃迁和伽利略相对性 ▲ 作者：Max T. Birch, Ilya Belopolski et al. ▲链接： https://www.nature.com/articles/s41586-024-07859-2 ▲摘要： 在这里，我们陈述了Gd2PdSi3中由其显著的拓扑霍尔效应（THE）所增进的斯格明子晶格（SkL）活动激发的新兴电动力学现象。跟着电流鼓励的增添，我们不雅察到SkL活动从钉住状况到蠕变状况，最后到活动状况的动态改变，此中THE完全被按捺。 我们认为，即便在如今朝的化合物的复杂多带系统中，也能够在活动状况中恢复完全抵消所需要的伽利略相对性。另外，我们不雅察到的电压足够年夜，可以及时丈量SkL的速度 电流曲线。该曲线显示SkL在蠕变状况下的惯性活动，表示为斯格明子速度的电流滞后现象。 ▲ Abstract： Here we report the emergent electrodynamics induced by SkL motion in Gd2PdSi3, facilitated by its giant THE. With increasing current excitation, we observe the dynamic transition of the SkL motion from the pinned to creep regime and finally to the flow regime, in which the THE is totally suppressed. We argue that the Galilean relativity required for the total cancellation of the THE may be generically recovered in the flow regime, even in complex multiband systems such as the present compound. Moreover, the observed THE voltages are large enough to enable real-time measurement of the SkL velocity current profile, which shows the inertial-like motion of the SkL in the creep regime, appearing as the current hysteresis of the skyrmion velocity. 医学Medicine Frontostriatal salience network expansion in individuals in depression 抑郁症患者的额纹状体显著收集扩大 ▲ 作者：Charles J. Lynch, Immanuel G. Elbau et al. ▲链接： https://www.nature.com/articles/s41586-024-07805-2 ▲摘要： 在此，利用切确的函数映照和几个深度采样的个别样本，我们发现年夜大都抑郁症患者的额纹状体显著性收集在皮质中扩大了近两倍。这类效应在几个样本中是可复制的，首要是由收集鸿沟移动引发的，在分歧的个别中产生了三种分歧的入侵模式。 跟着时候的推移，显著性收集扩大是不变的，不受情感状况的影响，在芳华期后期抑郁爆发前的儿童中可以检测到。在1.5年的时候里，我们对患者进行了多达62次的纵向阐发，发现了额纹状体回路的连通性转变，追踪了特定症状的波动，并猜测了将来的快感缺少症状。 总之，这些发现肯定了一种特点样的年夜脑收集拓扑布局。它可能带来抑郁症的风险，和额纹状体回路中情感状况依靠性毗连的转变，这些转变可以猜测抑郁症状随时候的呈现缓和解。 ▲ Abstract： Here, using precision functional mapping and several samples of deeply sampled individuals, we found that the frontostriatal salience network is expanded nearly twofold in the cortex of most individuals with depression. This effect was replicable in several samples and caused primarily by network border shifts, with three distinct modes of encroachment occurring in different individuals. Salience network expansion was stable over time, unaffected by mood state and detectable in children before the onset of depression later in adolescence. Longitudinal analyses of individuals scanned up to 62 times over 1.5 years identified connectivity changes in frontostriatal circuits that tracked fluctuations in specific symptoms and predicted future anhedonia symptoms. Together, these findings identify a trait-like brain network topology that may confer risk for depression and mood-state-dependent connectivity changes in frontostriatal circuits that predict the emergence and remission of depressive symptoms over time. 地球科学Earth Science Decoding drivers of carbon flux attenuation in the oceanic biological pump 解码海洋生物泵中碳通量衰减的驱动身分 ▲ 作者：M. Bressac, E. C. Laurenceau-Cornec et al. ▲链接： https://www.nature.com/articles/s41586-024-07850-x ▲摘要： 在此，我们展现了C-RESPIRE的原位尝试成果。C-RESPIRE是一种摆设在多个中层深度的双粒子阻挡器和培育箱，用在丈量微生物介导的颗粒有机碳（POC）通量衰减。 我们发现，在6个分歧的海洋系统中，即POC通量的30倍规模内，颗粒附着微生物的降解为通量衰减的7% 29%，这意味着浮游动物在通量衰减中阐扬了更年夜的影响感化。微生物再矿化，尺度化到POC通量，在分歧的地址和深度规模20倍，在高POC通量下速度最低。 高达三倍转变的垂直趋向与低纬度地域强烈的温度梯度有关。与之相反，在中高纬度地域，温度的影响较小，而垂直趋向可能由颗粒生物化学、破裂化和微生物生态心理配合决议。马丁曲线的解构揭露了驱动微生物介导的POC通量衰减的根基机制。 ▲ Abstract： Here we present in situ experimental findings from C-RESPIRE, a dual particle interceptor and incubator deployed at multiple mesopelagic depths, measuring microbially mediated POC flux attenuation. We find that across six contrasting oceanic regimes, representing a 30-fold range in POC flux, degradation by particle-attached microbes comprised 7 29 per cent of flux attenuation, implying a more influential role for zooplankton in flux attenuation. Microbial remineralization, normalized to POC flux, ranged by 20-fold across sites and depths, with the lowest rates at high POC fluxes. Vertical trends, of up to threefold changes, were linked to strong temperature gradients at low-latitude sites. In contrast, temperature played a lesser role at mid- and high-latitude sites, where vertical trends may be set jointly by particle biochemistry, fragmentation and microbial ecophysiology. This deconstruction of the Martin curve reveals the underpinning mechanisms that drive microbially mediated POC flux attenuation across oceanic provinces. Observation-constrained projections reveal longer-than-expected dry spells 猜测显示干旱期将擅长预期 ▲ 作者：Irina Y. Petrova, Diego G. Miralles et al. ▲链接： https://www.nature.com/articles/s41586-024-07887-y ▲摘要： 在此，我们注解利用新提出的告急束缚（EC）来束缚模子猜测，可以在全球规模内将焦点干旱指标 最终年度干旱期（LAD） 猜测的不肯定性下降10% 26%。经EC校订后的猜测成果显示，与今朝猜测的将来感化力情形比拟，LAD的平均增幅将超出跨越42% 44%。这些成果注解，到本世纪末，全球平均仅陆地的LAD可能比今朝估计的要长10天。 操纵两代天气模式，我们进一步揭露了汗青LAD误差影响预估LAD增添幅度的全球区域，并切磋了陆地 年夜气反馈在此中的感化。我们的研究成果揭露了一些地域的社会和生态系统可能面对比预期更高、更早的干旱风险，并指出了当前一代天气模子中存在误差的可能机制。 ▲ Abstract： Here we show that constraining model projections with observations using a newly proposed emergent constraint (EC) reduces the uncertainty in predictions of a core drought indicator, the longest annual dry spell (LAD), by 10 26% globally. Our EC-corrected projections reveal that the increase in LAD will be 42 44% greater, on average, than mid-range or high-end future forcing scenarios currently indicate. These results imply that by the end of this century, the global mean land-only LAD could be 10 days longer than currently expected. Using two generations of climate models, we further uncover global regions for which historical LAD biases affect the magnitude of projected LAD increases, and we explore the role of land atmosphere feedbacks therein. Our findings reveal regions with potentially higher- and earlier-than-expected drought risks for societies and ecosystems, and they point to possible mechanisms underlying the biases in the current generation of climate models. A climate threshold for ocean deoxygenation during the Early Cretaceous 白垩纪初期海洋脱氧的天气阈值 ▲ 作者：Kohen W. Bauer, N. Ryan McKenzie et al. ▲链接： https://www.nature.com/articles/s41586-024-07876-1 ▲摘要： 在此，我们的研究显示，在白垩纪年夜洋缺氧事务（OAE1a）时代海洋快速脱氧与火山二氧化碳排放和相干天气阈值的逾越有关。尔后，硅酸盐风化反馈和蔼候恢复的迟缓程序将再氧化的延迟事务年夜在1百万年。在OAE1a竣事时，从头超出这个阈值并使得海洋再氧化。 但是，在OAE1a以后，地球系统连结足够的暖和，以致在轨道驱动的天气动力学致使海洋在年夜约10亿年的时候标准上继续轮回脱氧，并延续了1百万年。是以，我们的成果暗示了火山感化、风化感化和海洋氧含量之间的慎密耦合，这类耦合以天气阈值为特点。 ▲ Abstract： Here we show that rapid ocean deoxygenation during OAE1a is linked to volcanic CO2emissions and the crossing of an associated climate threshold,开云体育app after which the sluggish pace of the silicate-weathering feedback and climate recovery delayed reoxygenation for 1 Myr. At the end of OAE1a, recrossing this threshold allowed for ocean reoxygenation. Following OAE1a, however, the Earth system remained sufficiently warm such that orbitally forced climate dynamics led to continued cyclic ocean deoxygenation on approximately 100-kyr timescales for another 1 Myr. Our results thus imply a tight coupling between volcanism, weathering and ocean oxygen content that is characterized by a climate threshold.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。
