Altering a material's catalytic properties would require identifying structural features that deliver electrochemically active surfaces. Single‐crystalline porous materials, combining the advantages ...of long‐range ordering of bulk crystals and large surface areas of porous materials, would create sufficient active surfaces by stabilizing 2D active moieties confined in lattice and may provide an alternative way to create high‐energy surfaces for electrocatalysis that are kinetically trapped. Here, a radical concept of building active metal–nitrogen moieties with unsaturated nitrogen coordination on a porous surface by directly growing metallic porous metal nitride (Fe3N and Ta5N6) single crystals at unprecedented 2 cm scale is reported. These porous single crystals demonstrate exceptionally high conductivity of 0.1–1.0 × 105 S cm−1, while the atomic surface layers of the porous crystals are confirmed to be an Fe termination layer for Fe3N and a Ta termination layer for Ta5N6. The unsaturated metal–nitrogen moieties (Fe6–N and Ta5–N3) with unique electronic structures demonstrate enhanced electrocatalysis performance and durability.
Metallic porous metal nitride (Fe3N and Ta5N6) single crystals with high conductivity and an atomic metal termination layer are grown at unprecedented 2 cm scale. The unsaturated metal–nitrogen moieties (Fe6–N and Ta5–N3) with unique electronic structures exhibit enhanced electrocatalysis performance and durability for CO2 reduction and H2 generation.
In this work, a simple strategy is developed to synthesize hierarchical tubular structures (HTS) of Mn‐based (Co‐Mn, Ni‐Mn, Cu‐Mn, Zn‐Mn) mixed metal oxides. The first step in the synthesis involves ...redox reaction mediated growth of nanoflakes on carbon nanofibers under hydrothermal conditions. After calcination in air, carbon nanofibers are removed and HTS of mixed metal oxides can be obtained with little structural deterioration. The resultant HTS are advantageous as electrodes for electrochemical energy storage. As an example, it is shown that the Co‐Mn‐HTS sample exhibits outstanding electrochemical performance as electrode materials for hybrid supercapacitors and lithium ion batteries.
A general strategy is developed for the synthesis of hierarchical tubular structures of Mn‐based mixed metal oxides. The derived Co‐Mn mixed oxide hierarchical tubular structures manifest enhanced electrochemical properties as electrodes for both hybrid supercapacitors and lithium ion batteries.
Top-down attention is crucial for meaningful behaviors and impaired in various mental disorders. However, its underpinning regulatory mechanisms are poorly understood. We demonstrate that the ...hippocampal-prefrontal synchrony associates with levels of top-down attention. Both attention and synchrony are reduced in mutant mice of ErbB4, a receptor of neuregulin-1. We used chemical genetic and optogenetic approaches to inactivate ErbB4 kinase and ErbB4+ interneurons, respectively, both of which reduce gamma-aminobutyric acid (GABA) activity. Such inhibitions in the hippocampus impair both hippocampal-prefrontal synchrony and top-down attention, whereas those in the prefrontal cortex alter attention, but not synchrony. These observations identify a role of ErbB4-dependent GABA activity in the hippocampus in synchronizing the hippocampal-prefrontal pathway and demonstrate that acute, dynamic ErbB4 signaling is required to command top-down attention. Because both neuregulin-1 and ErbB4 are susceptibility genes of schizophrenia and major depression, our study contributes to a better understanding of these disorders.
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•Hippocampal-prefrontal synchrony positively correlates with top-down attention level•Acute ErbB4 signaling regulates top-down attention•ErbB4-dependent GABA activity in hippocampus synchronizes PFC neurons in attention
Top-down attention is important for cognitive function, but its underpinning mechanisms are not well understood. Tan et al. demonstrate that attention correlates with hippocampal-prefrontal synchrony, both of which require acute, dynamic activity of ErbB4.
Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept ...in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health.
The neuromuscular junction (NMJ) is a tripartite synapse that is formed by motor nerve terminals, postjunctional muscle membranes, and terminal Schwann cells (TSCs) that cover the nerve-muscle ...contact. NMJ formation requires intimate communications among the three different components. Unlike nerve-muscle interaction, which has been well characterized, less is known about the role of SCs in NMJ formation and maintenance. We show that SCs in mice lead nerve terminals to prepatterned AChRs. Ablating SCs at E8.5 (i.e., prior nerve arrival at the clusters) had little effect on aneural AChR clusters at E13.5, suggesting that SCs may not be necessary for aneural clusters. SC ablation at E12.5, a time when phrenic nerves approach muscle fibers, resulted in smaller and fewer nerve-induced AChR clusters; however, SC ablation at E15.5 reduced AChR cluster size but had no effect on cluster density, suggesting that SCs are involved in AChR cluster maturation. Miniature endplate potential amplitude, but not frequency, was reduced when SCs were ablated at E15.5, suggesting that postsynaptic alterations may occur ahead of presynaptic deficits. Finally, ablation of SCs at P30, after NMJ maturation, led to NMJ fragmentation and neuromuscular transmission deficits. Miniature endplate potential amplitude was reduced 3 d after SC ablation, but both amplitude and frequency were reduced 6 d after. Together, these results indicate that SCs are not only required for NMJ formation, but also necessary for its maintenance; and postsynaptic function and structure appeared to be more sensitive to SC ablation.
Neuromuscular junctions (NMJs) are critical for survival and daily functioning. Defects in NMJ formation during development or maintenance in adulthood result in debilitating neuromuscular disorders. The role of Schwann cells (SCs) in NMJ formation and maintenance was not well understood. We genetically ablated SCs during development and after NMJ formation to investigate the consequences of the ablation. This study reveals a critical role of SCs in NMJ formation as well as maintenance.
This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized ...cultivation in Southeast China. Based on the constant total nitrogen application amounts (225.00 kg ha−1) in the main crop, an experiment with different ratios of basal and topdressing nitrogen fertilizer (the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4 (N1), 3:2:1:4 (N2), 3:3:0:4 (N3), and 4:3:0:3 (N4), respectively, and a control without nitrogen treatment (N0)) was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test materials. The results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment, more nitrogen fertilizer applied in late growth stage of the main crop, and its effective tillering percentage of the main crop was the highest at up to 70.18%, which was 9.15% higher than that of conventional fertilization treatment (N4), more nitrogen fertilizer applied in early growth stage of the main crop. The same tendency was observed in leaf area index (LAI) value of the main crop and its subsequent ratoon rice, which were 16.52 and 29.87% higher, respectively, in the N1 treatment than that in the N4 treatment at the full heading stage. The same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon crops. The transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57% compared with N4 treatment. The canopy light interception rate of N1 treatment increased by 5.07% compared with N4 treatment at the full heading stage of the ratoon crop. Therefore, the total actual yield was the highest in the main and its ratoon crops under N1 treatment, averaging 17 351.23 kg ha−1 in two-year trials, which was 23.00% higher than that in the conventional fertilization treatment (N4). The results showed that appropriate nitrogen treatment was able to produce a good crop stand in the main crop, which was essential for producing a good ratoon crop population and high yield especially under mechanized cultivation with low stubble height of the main crop. The study suggested that shifting the proper nitrogen application amounts to the late growth stage of the main crop, such as N1 treatment, not only had a higher productive effect on ensuring the yield of the main crop, but also had a positive effect on the axillary bud sprouts from the stubbles for ratoon rice, resulting in an increased percentage of productive panicles and achieving the goal of one planting with two good harvests under the conditions of our study.
To determine if patients with myasthenia gravis (MG) have antibodies to agrin, a proteoglycan released by motor neurons and is critical for neuromuscular junction (NMJ) formation, we collected serum ...samples from 93 patients with MG with known status of antibodies to acetylcholine receptor (AChR), muscle specific kinase (MuSK) and lipoprotein-related 4 (LRP4) and samples from control subjects (healthy individuals and individuals with other diseases). Sera were assayed for antibodies to agrin. We found antibodies to agrin in 7 serum samples of MG patients. None of the 25 healthy controls and none of the 55 control neurological patients had agrin antibodies. Two of the four triple negative MG patients (i.e., no detectable AChR, MuSK or LRP4 antibodies, AChR-/MuSK-/LRP4-) had antibodies against agrin. In addition, agrin antibodies were detected in 5 out of 83 AChR+/MuSK-/LRP4- patients but were not found in the 6 patients with MuSK antibodies (AChR-/MuSK+/LRP4-). Sera from MG patients with agrin antibodies were able to recognize recombinant agrin in conditioned media and in transfected HEK293 cells. These sera also inhibited the agrin-induced MuSK phosphorylation and AChR clustering in muscle cells. Together, these observations indicate that agrin is another autoantigen in patients with MG and agrin autoantibodies may be pathogenic through inhibition of agrin/LRP4/MuSK signaling at the NMJ.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Excessive mitophagy for anxiety Wang, Hongsheng; Xiong, Wen-Cheng; Mei, Lin
Neuron (Cambridge, Mass.),
12/2021, Letnik:
109, Številka:
23
Journal Article
Recenzirano
In this issue of Neuron, Duan et al. (2021) identified excessive mitophagy in BLA neurons synapsing onto adBNST neurons as a mechanism for reduced neurotransmission and social defeat-induced ...anxiety-like behaviors.