Garnet‐type electrolytes suffer from unstable chemistry against air exposure, which generates contaminants on electrolyte surface and accounts for poor interfacial contact with the Li metal. Thermal ...treatment of the garnet at >700 °C could remove the surface contaminants, yet it regenerates the contaminants in the air, and aggravates the Li dendrite issue as more electron‐conducting defective sites are exposed. In a departure from the removal approach, here we report a new surface chemistry that converts the contaminants into a fluorinated interface at moderate temperature <180 °C. The modified interface shows a high electron tunneling barrier and a low energy barrier for Li+ surface diffusion, so that it enables dendrite‐proof Li plating/stripping at a high critical current density of 1.4 mA cm−2. Moreover, the modified interface exhibits high chemical and electrochemical stability against air exposure, which prevents regeneration of contaminants and keeps high critical current density of 1.1 mA cm−2. The new chemistry presents a practical solution for realization of high‐energy solid‐state Li metal batteries.
The detrimental contaminants on a garnet surface are converted into an air‐stable fluorinated interface by a facile chemical approach at moderate temperature (<180 °C). The modified interface shows a high electron tunneling barrier and a low energy barrier for Li+ surface diffusion, enabling a high critical current density of 1.4 mA cm−2.
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Summary
Aims
To explore the role and underlying mechanism of miR‐124 in stroke.
Methods
miR‐124 expression was determined by real‐time PCR. The effect of miR‐124 on infarct area was assessed in ...middle cerebral artery occlusion (MCAO) mice. The influence of miR‐124 on oxygen and glucose deprivation (OGD) induced neuron apoptosis and death was examined by immunofluorescence. The effect of miR‐124 on apoptosis‐related proteins was determined by Western blot.
Results
The level of miR‐124 is significantly increased in ischemic penumbra as compared with that in nonischemic area of MACO mice. Brain tissue of stroke‐prone spontaneously hypertensive rats (SHR‐SP) also showed higher level of miR‐124 as compared with that of spontaneously hypertensive rats (SHR). Consistently, OGD treatment obviously increased miR‐124 level in primary neurons. In vivo, miR‐124 overexpression significantly decreased, while miR‐124 knockdown significantly increased, the infarct area of MCAO mice. In vitro, gain or loss of miR‐124 function resulted in reduced or increased neuron apoptosis and death induced by OGD, and increased or reduced antiapoptosis protein, Bcl‐2 and Bcl‐xl, respectively.
Conclusions
miR‐124 plays a neurons‐protective role via apoptosis‐inhibiting pathway in ischemic stroke.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Mesenchymal stem cell (MSC) transplantation is a promising treatment strategy for spinal cord injury, but immunological rejection and possible tumor formation limit its application. The therapeutic ...effects of MSCs mainly depend on their release of soluble paracrine factors. Exosomes are essential for the secretion of these paracrine effectors. Bone marrow mesenchymal stem cell-derived exosomes (BMSC-EXOs) can be substituted for BMSCs in cell transplantation. However, the underlying mechanisms remain unclear. In this study, a rat model of T10 spinal cord injury was established using the impact method. Then, 30 minutes and 1 day after spinal cord injury, the rats were administered 200 μL exosomes via the tail vein (200 μg/mL; approximately 1 × 106 BMSCs). Treatment with BMSC-EXOs greatly reduced neuronal cell death, improved myelin arrangement and reduced myelin loss, increased pericyte/endothelial cell coverage on the vascular wall, decreased blood-spinal cord barrier leakage, reduced caspase 1 expression, inhibited interleukin-1β release, and accelerated locomotor functional recovery in rats with spinal cord injury. In the cell culture experiment, pericytes were treated with interferon-γ and tumor necrosis factor-α. Then, Lipofectamine 3000 was used to deliver lipopolysaccharide into the cells, and the cells were co-incubated with adenosine triphosphate to simulate injury in vitro. Pre-treatment with BMSC-EXOs for 8 hours greatly reduced pericyte pyroptosis and increased pericyte survival rate. These findings suggest that BMSC-EXOs may protect pericytes by inhibiting pyroptosis and by improving blood-spinal cord barrier integrity, thereby promoting the survival of neurons and the extension of nerve fibers, and ultimately improving motor function in rats with spinal cord injury. All protocols were conducted with the approval of the Animal Ethics Committee of Zhengzhou University on March 16, 2019.
A synthetic strategy based on biogenetic building blocks for the collective and divergent biomimetic synthesis of cleistoperlones A−F, a cinnamoylphloroglucinol collection discovered from ...Cleistocalyx operculatus, has been developed. These syntheses proceeded successfully in only six to seven steps starting from commercially available 1,3,5‐benzenetriol and involving oxidative activation of stable biogenetic building blocks as a crucial step. Key features of the syntheses include a unique Michael addition/ketalization/1,6‐addition/enol‐keto tautomerism cascade reaction for the construction of the dihydropyrano3,2‐dxanthene tetracyclic core of cleistoperlones A and B, and a rare inverse‐electron‐demand hetero‐Diels–Alder cycloaddition for the establishment of benzopyran ring in cleistoperlones D−F. Moreover, cleistoperlone A exhibited significant antiviral activity against acyclovir‐resistant strains of herpes simplex virus type 1 (HSV‐1/Blue and HSV‐1/153).
Four novel cinnamoylphloroglucinol dimers were discovered from C. operculatus. Biomimetic syntheses of these and two known dimers were developed through a strategy in which the activation of stable biogenetic building blocks was a crucial step and key features included a unique cascade reaction and a rare inverse‐electron‐demand Diels–Alder reaction. One of the dimers showed activity against herpes simplex virus type 1 through a new mode of action.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The hybrid flowshop scheduling (HFS) problem with the objective of minimising the makespan has important applications in a variety of industrial systems. This paper presents an effective discrete ...artificial bee colony (DABC) algorithm that has a hybrid representation and a combination of forward decoding and backward decoding methods for solving the problem. Based on the dispatching rules, the well-known NEH heuristic, and the two decoding methods, we first provide a total of 24 heuristics. Next, an initial population is generated with a high level of quality and diversity based on the presented heuristics. A new control parameter is introduced to conduct the search of employed bees and onlooker bees with the intention of balancing the global exploration and local exploitation, and an enhanced strategy is proposed for the scout bee phase to prevent the algorithm from searching in poor regions of the solution space. A problem-specific local refinement procedure is developed to search for solution space that is unexplored by the honey bees. Afterward, the parameters and operators of the proposed DABC are calibrated by means of a design of experiments approach. Finally, a comparative evaluation is conducted, with the best performing algorithms presented for the HFS problem under consideration, and with adaptations of some state-of-the-art metaheuristics that were originally designed for other HFS problems. The results show that the proposed DABC performs much better than the other algorithms in solving the HFS problem with the makespan criterion.
•We present a novel discrete artificial bee colony algorithm to minimize makespan for the hybrid flowshop scheduling problem.•A total of 24 heuristics are provided to generate a good initial population.•A new hybrid representation combining the forward decoding and backward decoding method are proposed.•A new control parameter is introduced to balance the global exploration and local exploitation.•Computational and statistical analyses show the superiority of the presented approach.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Viral-encoded auxiliary metabolic genes (AMGs) are important toolkits for modulating their hosts' metabolisms and the microbial-driven biogeochemical cycles. Although the functions of AMGs have been ...extensively reported in numerous environments, we still know little about the drivers that shape the viral community-wide AMG compositions in natural ecosystems. Exploring the drivers of viral community-wide AMG compositions is critical for a deeper understanding of the complex interplays among viruses, hosts, and the environments.
Here, we investigated the impact of viral lifestyles (i.e., lytic and lysogenic), habitats (i.e., water, particle, and sediment), and prokaryotic hosts on viral AMG profiles by utilizing metagenomic and metatranscriptomic techniques. We found that viral lifestyles were the most important drivers, followed by habitats and host identities. Specifically, irrespective of what habitats viruses came from, lytic viruses exhibited greater AMG diversity and tended to encode AMGs for chaperone biosynthesis, signaling proteins, and lipid metabolism, which could boost progeny reproduction, whereas temperate viruses were apt to encode AMGs for host survivability. Moreover, the lytic and temperate viral communities tended to mediate the microbial-driven biogeochemical cycles, especially nitrogen metabolism, in different manners via AMGs. When focusing on each lifestyle, we further found clear dissimilarity in AMG compositions between water and sediment, as well the divergent AMGs encoded by viruses infecting different host orders.
Overall, our study provides a first systematic characterization of the drivers of viral community-wide AMG compositions and further expands our knowledge of the distinct interactions of lytic and temperate viruses with their prokaryotic hosts from an AMG perspective, which is critical for understanding virus-host-environment interactions in natural conditions. Video Abstract.
The development of high energy electrode materials for lithium ion batteries is challenged by their inherent instabilities, which become more aggravated as the energy densities continue to climb, ...accordingly causing increasing concerns on battery safety and reliability. Here, taking the high voltage cathode of LiNi0.5Mn1.5O4 as an example, we demonstrate a protocol to stabilize this cathode through a systematic phase modulating on its particle surface. We are able to transfer the spinel surface into a 30 nm shell composed of two functional phases including a rock-salt one and a layered one. The former is electrochemically inert for surface stabilization while the latter is designated to provide necessary electrochemical activity. The precise synthesis control enables us to tune the ratio of these two phases, and achieve an optimized balance between improved stability against structural degradation without sacrificing its capacity. This study highlights the critical importance of well-tailored surface phase property for the cathode stabilization of high energy lithium ion batteries.
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The conductive framework is generating considerable interest for lithium metal anodes to accommodate Li+ deposition, due to its ability to reduce electrode current density by increasing the ...deposition area. However, in most cases, the electroactive surface area is not fully utilized for the nucleation of Li in 3D current collectors, especially under high current densities. Herein, uniform nucleation of Li in the conductive skeleton is achieved by a two-step synergetic process arising from CuBr- and Br-doped graphene-like film. The modified electrode regulates Li nucleating in uniform pancake-like seeds and growing into a granular Li metal ascribed to the excellent lithiophilicity of CuBr- and Br-doping sites and the low Li diffusion barrier on the surface of generated LiBr, as confirmed by the experimental and computational results. Therefore, the modified anode endows small nucleation overpotential, a high-reversibility Li plating/stripping process, and excellent performance in full batteries with industrially significant cathode loading. This work suggests that a two-step cooperative strategy opens a viable route to the development of a Li anode with high reversibility for stable cycling Li metal batteries.
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Hollow nanostructures of metal oxides have found broad applications in different fields. Here, we reported a facile and versatile synthetic protocol to prepare hollow metal oxide nanospheres by ...modulating the chemical properties in solid nanoparticles. Our synthesis design starts with the precipitation of urea-containing metal oxalate, which is soluble in water but exists as solid nanospheres in ethanol. A controlled particle hydrolysis is achieved through the heating-induced urea decomposition, which transforms the particle composition in an outside-to-inside style: The reaction starts from the surface and then proceeds inward to gradually form a water-insoluble shell of basic metal oxalate. Such a reaction-induced solubility difference inside nanospheres becomes highly efficient to create a hollow structure through a simple water wash process. A following high temperature treatment forms hollow nanospheres of different metal oxides with structural features suited to their applications. For example, a high performance anode for Li-ion intercalation pseudocapacitor was demonstrated with the hollow and mesoporous Nb2O5 nanospheres.
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•The electronic and optical properties of multi-layer Bi2O2X (X = S, Se, Te) are systematically studied by the first principles calculations.•The Z-Bi2O2X and H-Bi2O2X always maintain ...direct and indirect band gap respectively with the increasing layer numbers.•The imaginary part of the dielectric function and the absorption spectrum of the H-Bi2O2S shift to low-energy (redshift) with the increasing layer numbers.•The Bi2O2X is a promising tunable photoelectric material by changing the layer numbers and strain modulation.
Two-dimensional (2D) Bi2O2X (X = S, Se, Te) have been reported to be promising optoelectronic materials, which have attracted immense attention from researchers. Adjustable optoelectronic materials are very important for the design and application of the device, but how to design its electronic and optical properties is rarely studied. In this research, we have systematically investigated the electronic and optical properties of 2D Bi2O2X (X = S, Se, Te), especially the response based on the number of layers and the strength of strain. We have found the lattice constants and the band gaps of the H-Bi2O2X and Z-Bi2O2X decrease as the number of layers increases, and finally approach the values of the bulk phase. Moreover, the adjustment of the number of layers can change the range of H-Bi2O2S band gap very much, and can even be adjusted from blue light energy to infrared light energy. As the layer numbers increase, the peaks of the imaginary part of the dielectric function and the absorption spectrum of H-Bi2O2S shift to low-energy region (redshift). Furthermore, the band gaps of H-Bi2O2X (X = S, Se, Te), Z-Bi2O2S, and Z-Bi2O2Se increase first and decrease with the increasing compress strain, and that decrease linearly with the increasing tensile strain. Surprisingly, with the increase of tensile strain, the band gap of Z-Bi2O2Te increases first and then decreases instead of the linear decrease like other materials, which may be due to the heavier Te atoms. Our HSE06 calculation results show that the Bi2O2X is a promising tunable photodetector with a broadband photoresponse in the visible light range.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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