Under the background of “carbon peaking” and “carbon neutralization”, the green transformation of iron and steel enterprises is imminent. The hydrogen-rich smelting technology of blast furnaces is very important for reducing energy consumption and CO2 emission in ironmaking systems, and it is one of the important directions of green and low-carbon development of iron and steel enterprises. In this paper, the research status of the thermal state, reduction mechanism of iron-bearing burden, coke degradation behavior, and formation of the cohesive zone in various areas of blast furnace after hydrogen-rich smelting is summarized, which can make a more clear and comprehensive understanding for the effect of H2 on blast furnace ironmaking. Meanwhile, based on the current research situation, it is proposed that the following aspects should be further studied in the hydrogen-rich smelting of blast furnaces: (1) the utilization rate of hydrogen and degree of substitution for direct reduction, (2) combustion behavior of fuel in raceway, (3) control of gas flow distribution in the blast furnace, (4) operation optimization of the blast furnace.

Achieving optimal behavior requires animals to flexibly retrieve prior knowledge. Here we show that adult newborn granule cells (anbGCs) mediate emotional-state-dependent plasticity of memory retrieval. We find that acute social reward (aSR) enhances memory retrieval by increasing the reactivation of engram cells, while acute social stress (aSS) weakens retrieval and reduces the reactivation. Such bidirectional regulation relies on the activation of distinct populations of anbGCs by aSR and aSS, triggering opposing modifications of dDG activity, which is sufficient to regulate and predict the performance of memory retrieval. Concordantly, in emotional disorder models, aSR-dependent memory plasticity is impaired, while the effect of aSS remains intact. Together, our data revealed that anbGCs mediate plasticity of memory retrieval, allowing animals to flexibly retrieve memory according to the current emotional state, and suggested the essential roles of anbGCs in translating emotional information to the regulation of memory expression.

Achieving optimal behavior requires animals to flexibly retrieve prior knowledge. Here, we show that adult newborn granule cells (anbGCs) mediate emotional state–dependent adaptability of memory retrieval. We find that acute social reward (aSR) enhances memory retrieval by increasing the reactivation of engram cells, while acute social stress (aSS) weakens retrieval and reduces the reactivation. Such bidirectional regulation relies on the activation of distinct populations of anbGCs by aSR and aSS, triggering opposing modifications of dDG activity, which is sufficient to regulate and predict the performance of memory retrieval. Concordantly, in emotional disorder models, aSR-dependent memory adaptability is impaired, while the effect of aSS remains intact. Together, our data revealed that anbGCs mediate adaptability of memory retrieval, allowing animals to flexibly retrieve memory according to the current emotional state, and suggested the essential roles of anbGCs in translating emotional information to the regulation of memory expression.

The interrogation of functional neural circuits is crucial for uncovering how the brain works during diverse behaviors. Multi-area neurophysiological measurement systems with high temporal resolution are indispensable, especially for dissecting inter-region functional connectivity. Here, we develop a cross-region all-optical physiology system (CRAOP) that enables the simultaneous recording and manipulation of single-neuron activities in multiple brain areas. Based on spatiotemporal multiplexing, our system enables all-optical analysis in the cortex and hippocampus with a high frame rate and minimal time delay in inter-layer imaging and photostimulation. Combined with behavioral experiments, CRAOP provides all-optical evidence linking behavioral responses to neuronal connectivity in the primary visual cortex (V1) in live mice. Furthermore, we demonstrate that CRAOP can perturb the activity response of interregional cortical neurons to sensory stimuli according to their functional signatures. Overall, CRAOP provides an optical approach for mapping interlayer connectivity at the single-neuron level and for modifying neuronal responses in behaving animals.