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The north-south striking landform perpendicular to the dominant collision zone between the Indian and Eurasian plates was constructed in east-southern Tibet (EST) during the Late Miocene. The building processes remain ambiguous, partly owing to the lack of recognition of crustal-scale architecture. Here we deployed an east-west-oriented 120 km-long short-period dense array across the northwestern corner of EST. Results from P-wave receiver functions show a mid-crustal ductile detachment atop the crystalline basement of the eastern Lhasa terrane that has displaced the overlying crust including the upper part of the Yardong-Gulu Rift (YGR) eastward for about 100 km and an offset Moho geometry left behind beneath the Nyainqentanghla Range. Combined previous studies on the vertical heterogeneity in crustal strength beneath the YGR, a synthetic view implies a decoupled crustal architecture of EST to respond the dynamic interactions between the eastward extrusion of the Tibetan Plateau and the northward penetration of the Indian plate that constitutes the Eastern Himalayan Syntaxis. The integrated processes eventually brought active landform construction in the plateau’s interior and partly contributing to the contemporaneous intensification of monsoon in SE Asia.

Although the Himalayan-Tibetan orogen is a result of compressional tectonics, the orogen also hosts active rifts accommodating east-west extension orthogonal to the north-south India-Asia convergence. In this study we address the question of how the north-trending rifts were formed by conducting high-resolution seismic imaging survey across southeastern Tibet where the Cona rift is exposed. Our work shows that the crustal structures of this youngest rift in southern Tibet was constructed by multiple-scale structures that are decoupled with depth and long rift trend. We suggest this deformation style to have resulted from eastward extrusion of the middle and upper crust with increasing speeds to the north towards the Yarlunbg-Zangpo suture. The differential eastward extrusion in turn may have contributed to the formation and evolution of the eastern Himalayan syntaxis.

Mechanism driving continental growth on modern Earth has long been debated. By interpreting the long deep seismic reflection data across the ongoing India-Eurasia collision zone, the authors report crustal-scale magma accretion onto the south of central Lhasa terrane produced net continental growth.

β-Hydrogen elimination is a fundamental reaction in palladium catalysis, however, the eliminated β-hydrogen is usually attached to a sp 3 -carbon. Here, the authors report a palladium-catalyzed cross-coupling reaction involving a β-vinylic hydrogen elimination from an allylic palladium intermediate.

Transannular construction of medium-sized lactones is entropically unfavoured. Herein, the authors describe a strategy for valuable medium-sized lactone synthesis from available benzaldehydes by selective C-H bond functionalization via palladium carbene migratory insertion-enabled 1,4-palladium shift.

Summary: The Heck reaction, along with other cross-coupling reactions, led to a revolution in organic chemistry. In the last 50 years, metal-catalyzed, photo-induced, or base-mediated Heck and Heck-type reactions have been elegantly developed. Brønsted acid-catalyzed Heck (or Heck-type) reactions are still unknown, however. By introducing alkyl peroxides as the key intermediates, primary, secondary, and tertiary aliphatic carboxylic acids are therefore applied here in a one-pot Brønsted acid-catalyzed Heck-type reaction, to deliver E-alkenes exclusively in most cases. The use of HOTf is vital to the reaction, whose mechanism is supported by both experimental and computational results. This method can be expanded to the direct alkylation of complex natural products. : Organic Synthesis; Organic Chemistry Methods; Natural Product Synthesis Subject Areas: Organic Synthesis, Organic Chemistry Methods, Natural Product Synthesis

Carbon dioxide electrolysers are promising for chemical storage of renewable electricity; however, achieving effective adsorption/activation of CO2 is still an issue. Here the authors make a perovskite titanate cathode where non-stoichiometry and chemical doping are used to tune the surface structures, facilitating CO2reduction.

Abstract Cutting-edge mid-wavelength infrared (MWIR) sensing technologies leverage infrared photodetectors, memory units, and computing units to enhance machine vision. Real-time processing and decision-making challenges emerge with the increasing number of intelligent pixels. However, current operations are limited to in-sensor computing capabilities for near-infrared technology, and high-performance MWIR detectors for multi-state switching functions are lacking. Here, we demonstrate a non-volatile MoS2/black phosphorus (BP) heterojunction MWIR photovoltaic detector featuring a semi-floating gate structure design, integrating near- to mid-infrared photodetection, memory and computing (PMC) functionalities. The PMC device exhibits the property of being able to store a stable responsivity, which varies linearly with the stored conductance state. Significantly, device weights (stable responsivity) can be programmed with power consumption as low as 1.8 fJ, and the blackbody peak responsivity can reach 1.68 A/W for the MWIR band. In the simulation of Faster Region with convolution neural network (CNN) based on the FLIR dataset, the PMC hardware responsivity weights can reach 89% mean Average Precision index of the feature extraction network software weights. This MWIR photovoltaic detector, with its versatile functionalities, holds significant promise for applications in advanced infrared object detection and recognition systems.

Abstract In-sensor processing has the potential to reduce the energy consumption and hardware complexity of motion detection and recognition. However, the state-of-the-art all-in-one array integration technologies with simultaneous broadband spectrum image capture (sensory), image memory (storage) and image processing (computation) functions are still insufficient. Here, macroscale (2 × 2 mm2) integration of a rippled-assisted optoelectronic array (18 × 18 pixels) for all-day motion detection and recognition. The rippled-assisted optoelectronic array exhibits remarkable uniformity in the memory window, optically stimulated non-volatile positive and negative photoconductance. Importantly, the array achieves an extensive optical storage dynamic range exceeding 106, and exceptionally high room-temperature mobility up to 406.7 cm2 V−1 s−1, four times higher than the International Roadmap for Device and Systems 2028 target. Additionally, the spectral range of each rippled-assisted optoelectronic processor covers visible to near-infrared (405 nm–940 nm), achieving function of motion detection and recognition.

Abstract Inflammation, caused by accumulation of inflammatory cytokines from immunocytes, is prevalent in a variety of diseases. Electro-stimulation emerges as a promising candidate for inflammatory inhibition. Although electroacupuncture is free from surgical injury, it faces the challenges of imprecise pathways/current spikes, and insufficiently defined mechanisms, while non-optimal pathway or spike would require high current amplitude, which makes electro-stimulation usually accompanied by damage and complications. Here, we propose a neuromorphic electro-stimulation based on atomically thin semiconductor floating-gate memory interdigital circuit. Direct stimulation is achieved by wrapping sympathetic chain with flexible electrodes and floating-gate memory are programmable to fire bionic spikes, thus minimizing nerve damage. A substantial decrease (73.5%) in inflammatory cytokine IL-6 occurred, which also enabled better efficacy than commercial stimulator at record-low currents with damage-free to sympathetic neurons. Additionally, using transgenic mice, the anti-inflammation effect is determined by β2 adrenergic signaling from myeloid cell lineage (monocytes/macrophages and granulocytes).

Abstract Neuromorphic computing can efficiently handle data‐intensive tasks and address the redundant interaction required by von Neumann architectures. Synaptic devices are essential components for neuromorphic computation. 2D phosphorene, such as violet phosphorene, show great potential in optoelectronics due to their strong light‐matter interactions, while current research is mainly focused on synthesis and characterization, its application in photoelectric devices is vacant. Here, the authors combined violet phosphorene and molybdenum disulfide to demonstrate an optoelectronic synapse with a light‐to‐dark ratio of 106, benefiting from a significant threshold shift due to charge transfer and trapping in the heterostructure. Remarkable synaptic properties are demonstrated, including a dynamic range (DR) of > 60 dB, 128 (7‐bit) distinguishable conductance states, electro‐optical dependent plasticity, short‐term paired‐pulse facilitation, and long‐term potentiation/depression. Thanks to the excellent DR and multi‐states, high‐precision image classification with accuracies of 95.23% and 79.65% is achieved for the MNIST and complex Fashion‐MNIST datasets, which is close to the ideal device (95.47%, 79.95%). This work opens the way for the use of emerging phosphorene in optoelectronics and provides a new strategy for building synaptic devices for high‐precision neuromorphic computing.

Summary: As the size of the transistor scales down, this strategy has confronted challenges because of the fundamental limits of silicon materials. Besides, more and more energy and time are consumed by the data transmission out of transistor computing because of the speed mismatching between the computing and memory. To meet the energy efficiency demands of big data computing, the transistor should have a smaller feature size and store data faster to overcome the energy burden of computing and data transfer. Electron transport in two-dimensional (2D) materials is constrained within a 2D plane and different materials are assembled by the van der Waals force. Owning to the atomic thickness and dangling-bond-free surface, 2D materials have demonstrated advantages in transistor scaling-down and heterogeneous structure innovation. In this review, from the performance breakthrough of 2D transistors, we discuss the opportunities, progress and challenges of 2D materials in transistor applications.

Reducing circuit redundancy represents a priority for the scalability of parallel computing hardware. Here, the authors report the realization of pixel processing units consisting of single 2D WSe2 transistors implementing electrically-switchable logic functions. This strategy enables the fabrication of an image processing array with ~16% transistor consumption compared to traditional circuits.

Abstract To meet the demands of future intelligent application scenarios, the time‐efficient information acquisition and energy‐efficient data processing capabilities of terminal electronic systems are indispensable. However, in current commercial visual systems, the visible information is collected by image sensors, converted into digital format data, and transferred to memory units and processors for subsequent processing tasks. As a result, most of the time and energy are wasted in the data conversion and movement, which leads to large time latency and low energy efficiency. Here, based on 2D semiconductor WSe2, a logic‐memory transistor that integrates visible information sensing‐memory‐processing capabilities is successfully demonstrated. Furthermore, based on 3 × 3 fabricated devices, an artificial visible information sensing‐memory‐processing system is proposed to perform image distinction tasks, in which the time latency and energy consumption caused by data conversion and movement can be avoided. On the other hand, the logic‐memory transistor can also execute digital logic processing (logic) and logic results storage (memory) at the same time, such as AND logic function. Such a logic‐memory transistor could provide a compact approach to develop next‐generation efficient visual systems.

Abstract The human memory system plays an indispensable role in oblivion, learning, and memorization. Implementing a memory system within electronic devices contributes an important step toward constructing a neuromorphic system that emulates advanced mental functions of the human brain. Given the complex time‐tailoring requirement, integrating a human memory system into one system is a great challenge. Here, one van der Waals heterostructure with flexible time‐tailoring ability is demonstrated, which can meet the high requirement of human memory system programming. By stacking volatile and nonvolatile function layers, all basic memory types, including sensory memory, short‐term and long‐term memory are integrated into the device and the transition between these memory types are flexible. Moreover, decision‐making action and in situ result storage are also demonstrated. It is anticipated that the demonstrated time‐tailoring system will support the model of a human memory system.