Abstract The endocannabinoid system (ECS) is a widespread neuromodulatory system that plays important roles in central nervous system development, synaptic plasticity, and the response to endogenous ...and environmental insults. The ECS comprises cannabinoid receptors, endogenous cannabinoids (endocannabinoids), and the enzymes responsible for the synthesis and degradation of the endocannabinoids. The most abundant cannabinoid receptors are the CB1 cannabinoid receptors; however, CB2 cannabinoid receptors, transient receptor potential channels, and peroxisome proliferator activated receptors are also engaged by some cannabinoids. Exogenous cannabinoids, such as tetrahydrocannabinol, produce their biological effects through their interactions with cannabinoid receptors. The best-studied endogenous cannabinoids are 2-arachidonoyl glycerol and arachidonoyl ethanolamide (anandamide). Despite similarities in chemical structure, 2-arachidonoyl glycerol and anandamide are synthesized and degraded by distinct enzymatic pathways, which impart fundamentally different physiologic and pathophysiologic roles to these two endocannabinoids. As a result of the pervasive social use of cannabis and the involvement of endocannabinoids in a multitude of biological processes, much has been learned about the physiologic and pathophysiologic roles of the ECS. This review provides an introduction to the ECS with an emphasis on its role in synaptic plasticity and how the ECS is perturbed in schizophrenia.
1,2,3,5-Tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) is a typical donor-acceptor fluorophore, with carbazolyl as an electron donor and dicyanobenzene as an electron acceptor. It has emerged as ...a powerful organophotocatalyst since 2016. Excellent redox window, good chemical stability and broad applicability make 4CzIPN an attractive metal-free photocatalyst. In this review, the recent advances of the application of 4CzIPN as a photoredox catalyst in the past three years (2016-2018) for various organic reactions are summarized.
In this review, the recent advances of the application of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as a photoredox catalyst in the past three years (2016-2018) for various organic reactions are summarized.
Hexagonal boron nitride (h‐BN) has lately received great attention in the oxidative dehydrogenation (ODH) reaction of propane to propylene for its extraordinary olefin selectivity in contrast to ...metal oxides. However, high crystallinity of commercial h‐BN and elusive cognition of active sites hindered the enhancement of utilization efficiency. Herein, four kinds of plasmas (N2, O2, H2, Ar) were accordingly employed to regulate the local chemical environment of h‐BN. N2‐treated BN exhibited a remarkable activity, i.e., 26.0 % propane conversion with 89.4 % selectivity toward olefins at 520 °C. Spectroscopy demonstrated that “three‐boron center” N‐defects in the catalyst played a pivotal role in facilitating the conversion of propane. While the sintering effect of the “BOx” species in O2‐treated BN, led to the suppressed catalytic performance (12.4 % conversion at 520 °C).
Plasma (N2, O2, H2, Ar) regulated h‐BN with distinct local environment were obtained and employed for ODH of propane: N2 treated BN containing more three‐boron center nitrogen‐defects exhibited remarkable propane conversion of 26.0 % with olefin selectivity of 89.4 % at 520 °C. O2 treated BN showed deactivation due to the sintering effect of “BOx”. N‐H and B‐H generated during H2 treatment, may be unable to facilitate the reaction activity.
Topological insulators with unique edge states have revolutionized the understanding of solid-state materials. Recently, higher-order topological insulators (HOTIs), which host both gapped edge ...states and in-gap corner/hinge states, protected concurrently by band topology, were predicted and observed in experiments, unveiling a new horizon beyond the conventional bulk-edge correspondence. However, the control and manifestation of band topology in a hierarchy of dimensions, which is at the heart of HOTIs, have not yet been witnessed. Here, we propose theoretically and observe experimentally that tunable two-dimensional sonic crystals can be versatile systems to visualize and harness higher-order topology. In our systems, the two-dimensional acoustic bands mimic the quantum spin Hall effect, while the resultant one-dimensional helical edge states are gapped due to broken space-symmetry and carry quantized Zak phases, which then lead to zero-dimensional topological corner states. We demonstrate that topological transitions in the bulk and edges can be triggered independently by tuning the geometry of the sonic crystals. With complementary experiments and theories, our study reveals rich physics in HOTIs, opening a new route towards tunable topological metamaterials where novel applications, such as the topological transfer of acoustic energy among two-, one- and zero-dimensional modes, can be achieved.By tuning the geometry of a two-dimensional sonic crystal, its one-dimensional helical edge states become gapped and zero-dimensional topological corner states emerge. The band topology is thus manifested in a hierarchy of dimensions.
Pre‐eclampsia (PE) is a leading cause of maternal and perinatal morbidity and mortality; however, the aetiology of PE still remains unclear. It has been widely accepted that the disease results from ...insufficient spiral artery remodelling, leading to placental ischaemia and the release of a variety of factors. In recent decades, a large number of studies have observed an abnormal immune response in preeclamptic women and studies of both patients and animal models have shown alterations in the function or the number of immune agents. Thus, researchers believe that alterations in the immune system may contribute to the genesis and pathophysiology of PE. Therefore, identifying the role of the immune system can not only shed light on the nature of PE but also contribute to the development of diagnostic and therapeutic methods for PE. This review focuses on the current knowledge of the immune system including both innate and adaptive immunity and sheds light on their role in PE. Additionally, advances in potential therapeutic measures are discussed.
Hydrogen has attracted much attention as a globally accepted clean energy carrier. Currently, the search for safe and efficient hydrogen storage materials is one of the most difficult challenges for ...the upcoming hydrogen economy. Boron- and nitrogen-based hydrides, such as metal borohydrides (
e.g.
NaBH
4
), ammonia borane (NH
3
BH
3
), ammonia (NH
3
), hydrous hydrazine (N
2
H
4
·H
2
O), and hydrazine borane (N
2
H
4
BH
3
), have received much attention as potential chemical hydrogen storage materials because of their high hydrogen contents and the advantage of CO-free H
2
produced. In recent years, substantial efforts have been devoted to research highly efficient catalysts to significantly improve the kinetic properties for hydrogen evolution from the hydrolysis of sodium borohydride and ammonia borane, and selective decomposition of ammonia, hydrous hydrazine and hydrazine borane. Among them, non-noble metal catalysts have been widely considered as potential candidates due to their low cost, abundant reserves, and relatively high catalytic activities. In this review, we focus on the recent advances in non-noble metal catalyst design, synthesis and applications in hydrogen generation from boron- and nitrogen-based hydrides.
We focus on the recent advances in non-noble metal catalyst design, synthesis and applications in dehydrogenation of chemical hydrides (
e.g.
NaBH
4
, NH
3
BH
3
, NH
3
, N
2
H
4
, N
2
H
4
BH
3
) due to their high hydrogen contents and CO-free H
2
production.
Beyond the scope of Hermitian physics, non-Hermiticity fundamentally changes the topological band theory, leading to interesting phenomena, e.g., non-Hermitian skin effect, as confirmed in ...one-dimensional systems. However, in higher dimensions, these effects remain elusive. Here, we demonstrate the spin-polarized, higher-order non-Hermitian skin effect in two-dimensional acoustic higher-order topological insulators. We find that non-Hermiticity drives wave localizations toward opposite edges upon different spin polarizations. More interestingly, for finite systems with both edges and corners, the higher-order non-Hermitian skin effect leads to wave localizations toward two opposite corners for all the bulk, edge and corner states in a spin-dependent manner. We further show that such a skin effect enables rich wave manipulation by configuring the non-Hermiticity. Our study reveals the intriguing interplay between higher-order topology and non-Hermiticity, which is further enriched by the pseudospin degree of freedom, unveiling a horizon in the study of non-Hermitian physics.
Hard carbon attracts considerable attention as an anode material for sodium‐ion batteries; however, their poor rate capability and low realistic capacity have motivated intense research effort toward ...exploiting nanostructured carbons in order to boost their comprehensive performance. Ultramicropores are considered essential for attaining high‐rate capacity as well as initial Coulombic efficiency by allowing the rapid diffusion of Na+ and inhibiting the contact of the electrolyte with the inner carbon surfaces. Herein, hard carbon nanosheets with centralized ultramicropores (≈0.5 nm) and easily accessible carbonyl groups (CO)/hydroxy groups (OH) are synthesized via interfacial assembly and carbonization strategies, delivering a large capacity (318 mA h g−1 at 0.02 A g−1), superior rate capability (145 mA h g−1 at 5.00 A g−1), and approximately 95% of reversible capacity below 1.00 V. Notably, a new charge model favoring fast capacitive sodium storage with dual potential plateaus is proposed. That is, the deintercalation of Na+ from graphitic layers is manifested as the low‐potential plateau region (0.01−0.10 V), contributing to stable insertion capacity; meanwhile, the surface desodiation process of the CO and OH groups corresponds to the high‐potential plateau region (0.40−0.70 V), contributing to a fast capacitive storage.
Hard carbon nanosheets with centralized ultramicropores (≈0.5 nm), accessible functional CO/OH groups, and large graphitic layer spacings exhibit excellent sodium‐storage properties. The desodiation process from graphitic layers and CO/OH groups results in a new sodium‐storage characteristic with dual‐potential plateaus during the charge process, which favors a high output of 95%, realistic capacity, and rapidly capacitive sodium storage.
Precise control of solid-state elastic waves' mode content and coherence is of great use nowadays in reinforcing mechanical energy harvesting/storage, nondestructive material testing, wave-matter ...interaction, high sensitivity sensing, and information processing, etc. Its efficacy is highly dependent on having elastic transmission channels with lower loss and higher degree of freedom. Here, we demonstrate experimentally an elastic analog of the quantum spin Hall effects in a monolithically scalable configuration, which opens up a route in manipulating elastic waves represented by elastic pseudospins with spin-momentum locking. Their unique features including robustness and negligible propagation loss may enhance elastic planar-integrated circuit-level and system-level performance. Our approach promotes topological materials that can interact with solid-state phonons in both static and time-dependent regimes. It thus can be immediately applied to multifarious chip-scale topological phononic devices, such as path-arbitrary elastic wave-guiding, elastic splitters and elastic resonators with high-quality factors.
While lithium-sulfur batteries are poised to be the next-generation high-density energy storage devices, the intrinsic polysulfide shuttle has limited their practical applications. Many recent ...investigations have focused on the development of methods to wrap the sulfur material with a diffusion barrier layer. However, there is a trade-off between a perfect preassembled wrapping layer and electrolyte infiltration into the wrapped sulfur cathode. Here, we demonstrate an in situ wrapping approach to construct a compact layer on carbon/sulfur composite particles with an imperfect wrapping layer. This special configuration suppresses the shuttle effect while allowing polysulfide diffusion within the interior of the wrapped composite particles. As a result, the wrapped cathode for lithium-sulfur batteries greatly improves the Coulombic efficiency and cycle life. Importantly, the capacity decay of the cell at 1000 cycles is as small as 0.03% per cycle at 1672 mA g
.To suppress the polysulfide shuttling effect in Li-S batteries, here the authors report a carbon/sulfur composite cathode with a wrapping layer that overcomes the trade-off between limiting polysulfide diffusion and allowing electrolyte infiltration, and affords extraordinary cycling stability.
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