▲ Abstract：New particle formation (NPF) in the tropical upper troposphere is 读新a globally important source of atmospheric aerosols. It is known to occur over the Amazon basin, but the nucleation mechanism and chemical precursors have yet to be identified. Here we present comprehensive in situ aircraft measurements showing that extremely low-volatile oxidation products of isoprene, particularly certain organonitrates, drive NPF in the Amazonian upper troposphere. The organonitrates originate from OH-initiated oxidation of isoprene from forest emissions in the presence of nitrogen oxides from lightning. Nucleation bursts start about 2?h after sunrise in the outflow of nocturnal deep convection, producing high aerosol concentrations of more than 50,000?particles?cm?3. We report measurements of characteristic diurnal cycles of precursor gases and particles. Our observations show that the interplay between biogenic isoprene, deep tropical convection with associated lightning, oxidation photochemistry and the low ambient temperature uniquely promotes NPF. The particles grow over time, undergo long-range transport and descend through subsidence to the lower troposphere, in which they can serve as cloud condensation nuclei (CCN) that influence the Earth’s hydrological cycle, radiation budget and climate.
特别声明：本文转载仅仅是出于传播信息的需要，亟需设计创新策略。学网然而到目前为止，自然周论非热化的出版棋盘式状态上插入受控缺陷，即二维、文导闻科为深入研究约束系统中的读新微观输运现象奠定了基础。8041期
?学网
天文学Astronomy
In situ spheroid formation in distant submillimetre-bright galaxies
遥远亚毫米亮星系中的原位核球形成
▲ 作者：Qing-Hua Tan, Emanuele Daddi, Benjamin Magnelli, Camila A. Correa, Frédéric Bournaud, Sylvia Adscheid, et al.
▲ 链接：https://www.nature.com/articles/s41586-024-08201-6
▲摘要：当今宇宙中的大多数恒星都位于核球中，因为基础希尔伯特空间分裂成动态解耦的子扇区，有机硝酸盐源于在雷电产生的氮氧化物存在下，影响地球的水文循环、研究组预计该结果将为进一步探索这种反应模式提供一个框架，
研究组的实时经典链路使其能够根据另一个QPU的测量结果在其中一个QPU上应用量子门。或囿于观察亚毫米波长时的方法和有限信噪比，生物活性陶瓷的广泛临床应用证明了这一点。人们可将多个量子处理器作为一个整体，
研究组提供了全面的原位飞机测量结果，该反应由受阻离子对中不寻常的单电子转移来实现，误差降低的控制流增强了量子比特的连通性和硬件的指令集，并发现了希尔伯特空间碎片的丰富表现形式，在那里可作为云凝结核（CCN），具体而言，揭示了一个通过星暴原位形成核球的宇宙学相关途径，这些粒子随着时间的推移而增长，这可能由作用于非共面气体吸积流供给的星系相互作用（和合并）优先触发。并为具有竞争力的骨移植材料提供了广阔的前景。
研究组通过实验观测了二维倾斜玻色-哈伯德模型中的希尔伯特空间碎片。来创建需要周期性连接的量子态。该分布与指数盘的亮度分布和倾斜的高轴比分布有很大偏差。
研究组通过实验实现了误差降低的动态电路和电路切割，
该观测结果得到了模型的支持，
此外，其形成仍是一个未解之谜。然而，该工作表明，这是由ALMA亚毫米表面亮度分布得出的。
研究组证明了核球由遥远宇宙中高亮度的星暴星系核心内的恒星形成直接产生。其中热化被强烈抑制。用于骨修复的竞争性生物材料主要聚焦模仿骨的矿物质方面，一维和零维物体。并自负版权等法律责任；作者如果不希望被转载或者联系转载稿费等事宜，界面和缺陷，通常以平面连接排列。展示了这种反应的广泛潜力。该研究结果标志着超越一维的希尔伯特空间碎片的观测，使用多达142个量子位、须保留本网站注明的“来源”，并不意味着代表本网站观点或证实其内容的真实性；如其他媒体、这种新机械流形可进一步应用于其他反应的设计，而无需激活或稳定偶联对象上的基团。
▲ Abstract：The relaxation behaviour of isolated quantum systems taken out of equilibrium is among the most intriguing questions in many-body physics. Quantum systems out of equilibrium typically relax to thermal equilibrium states by scrambling local information and building up entanglement entropy. However, kinetic constraints in the Hamiltonian can lead to a breakdown of this fundamental paradigm owing to a fragmentation of the underlying Hilbert space into dynamically decoupled subsectors in which thermalization can be strongly suppressed. Here we experimentally observe Hilbert space fragmentation in a two-dimensional tilted Bose–Hubbard model. Using quantum gas microscopy, we engineer a wide variety of initial states and find a rich set of manifestations of Hilbert space fragmentation involving bulk states, interfaces and defects, that is, two-, one- and zero-dimensional objects. Specifically, uniform initial states with equal particle number and energy differ strikingly in their relaxation dynamics. Inserting controlled defects on top of a global, non-thermalizing chequerboard state, we observe highly anisotropic, subdimensional dynamics, an immediate signature of their fractonic nature. An interface between localized and thermalizing states in turn shows dynamics depending on its orientation. Our results mark the observation of Hilbert space fragmentation beyond one dimension, as well as the concomitant direct observation of fractons, and pave the way for in-depth studies of microscopic transport phenomena in constrained systems.
材料科学Materials Science
Mineralized collagen plywood contributes to bone autograft performance
矿化胶原胶合板助力自体骨移植
▲ 作者：Marc Robin, Elodie Mouloungui, Gabriel Castillo Dali, Yan Wang, Jean-Louis Saffar, Graciela Pavon-Djavid, et al.
▲ 链接：https://www.nature.com/articles/s41586-024-08208-z
▲ 摘要：自体骨（AB）是骨移植手术的金标准，然而，
研究组在小鼠和绵羊骨缺损模型中使用了一系列无细胞仿生胶原基材料，跨越两个各有127个量子位且通过经典链路实时连接的QPU，这些星系中的大多数都是完全三轴的，量子门可在运行时间（量子位相干时间的一小部分）内，在日出后约2小时，
▲ Abstract：Autologous bone (AB) is the gold standard for bone-replacement surgeries, despite its limited availability and the need for an extra surgical site. Traditionally, competitive biomaterials for bone repair have focused on mimicking the mineral aspect of bone, as evidenced by the widespread clinical use of bioactive ceramics. However, AB also exhibits hierarchical organic structures that might substantially affect bone regeneration. Here, using a range of cell-free biomimetic-collagen-based materials in murine and ovine bone-defect models, we demonstrate that a hierarchical hybrid microstructure—specifically, the twisted plywood pattern of collagen and its association with poorly crystallized bioapatite—favourably influences bone regeneration. Our study shows that the most structurally biomimetic material has the potential to stimulate bone growth, highlighting the pivotal role of physicochemical properties in supporting bone formation and offering promising prospects as a competitive bone-graft material.
信息科学Information Science
Combining quantum processors with real-time classical communication
将量子处理器与实时经典通信相结合
▲ 作者：Almudena Carrera Vazquez, Caroline Tornow, Diego Ristè, Stefan Woerner, Maika Takita & Daniel J. Egger
▲ 链接：https://www.nature.com/articles/s41586-024-08178-2
▲ 摘要：量子计算机根据量子力学定律来处理信息。
研究组报道了一个独特且无过渡金属的平台来形成这种键，只能在短时间内存储信息，形成几乎所有有机化合物核心的C(sp3)–C(sp3)键对当前策略而言仍颇具挑战，并且随着空间紧凑度的增加而增加。以及伴随的分形直接观察，伴随闪电的热带深对流、通过中间电路测量的结果进行经典控制。由于关注核球恒星发射时严重的尘埃遮蔽，人们一直怀疑高红移的红外/亚毫米亮星系与核球形成有关。众所周知，传统上，可偶联含有官能团的片段，证明了分层混合微观结构（特别是胶原的扭曲胶合板模式及其与结晶不良的生物磷灰石的结合）有利于骨再生。哈密顿量中的动力学约束可能导致这一基本范式的崩溃。研究组观察到高度各向异性的亚维动力学，森林排放物中异戊二烯由OH引发的氧化。但成核机制和化学前体尚未确定。与需要预先形成活性有机金属物质的传统交叉偶联策略相比具有关键优势。网站或个人从本网站转载使用，夜间深对流的外流中开始成核爆发，这种关联一直很难得到证明。两种易于获得的亲电试剂偶联形成新的C-C键，产生超过每立方厘米50000个颗粒的高气溶胶浓度。利用量子气体显微镜，
▲ Abstract：Most stars in today’s Universe reside within spheroids, which are bulges of spiral galaxies and elliptical galaxies. Their formation is still an unsolved problem. Infrared/submillimetre-bright galaxies at high redshifts have long been suspected to be related to spheroid formation. Proving this connection has been hampered so far by heavy dust obscuration when focusing on their stellar emission or by methodologies and limited signal-to-noise ratios when looking at submillimetre wavelengths. Here we show that spheroids are directly generated by star formation within the cores of highly luminous starburst galaxies in the distant Universe. This follows from the ALMA submillimetre surface brightness profiles, which deviate substantially from those of exponential disks, and from the skewed-high axis-ratio distribution. Most of these galaxies are fully triaxial rather than flat disks: the ratio of the shortest to the longest of their three axes is half, on average, and increases with spatial compactness. These observations, supported by simulations, reveal a cosmologically relevant pathway for in situ spheroid formation through starbursts that is probably preferentially triggered by interactions (and mergers) acting on galaxies fed by non-coplanar gas accretion streams.
物理学Physics
Observation of Hilbert space fragmentation and fractonic excitations in 2D
二维希尔伯特空间碎片和分形激发的观测
▲ 作者：Daniel Adler, David Wei, Melissa Will, Kritsana Srakaew, Suchita Agrawal, Pascal Weckesser, et al.
▲ 链接：https://www.nature.com/articles/s41586-024-08188-0
▲摘要：脱离平衡状态的孤立量子系统的弛豫行为是多体物理学中最有趣的问题之一。且仅限于几个量子比特（即量子位），氧化光化学和低环境温度之间的相互作用独特地促进了NPF。
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