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Rechargeable lithium-ion batteries with high energy density that can be safely charged and discharged at high rates are desirable for electrified transportation and other applications1-3. However, the sub-optimal intercalation potentials of current anodes result in a trade-off between energy density, power and safety. Here we report that disordered rock salt4,5 Li3+xV2O5 can be used as a fast-charging anode that can reversibly cycle two lithium ions at an average voltage of about 0.6 volts versus a Li/Li+ reference electrode. The increased potential compared to graphite6,7 reduces the likelihood of lithium metal plating if proper charging controls are used, alleviating a major safety concern (short-circuiting related to Li dendrite growth). In addition, a lithium-ion battery with a disordered rock salt Li3V2O5 anode yields a cell voltage much higher than does a battery using a commercial fast-charging lithium titanate anode or other intercalation anode candidates (Li3VO4 and LiV0.5Ti0.5S2)8,9. Further, disordered rock salt Li3V2O5 can perform over 1,000 charge-discharge cycles with negligible capacity decay and exhibits exceptional rate capability, delivering over 40 per cent of its capacity in 20 seconds. We attribute the low voltage and high rate capability of disordered rock salt Li3V2O5 to a redistributive lithium intercalation mechanism with low energy barriers revealed via ab initio calculations. This low-potential, high-rate intercalation reaction can be used to identify other metal oxide anodes for fast-charging, long-life lithium-ion batteries.
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Neuroblastoma (NB), a common solid tumour in young children originating from the sympathetic nervous system during embryonic development, poses challenges despite therapeutic advances like high-dose chemotherapy and immunotherapy. Some survivors still grapple with severe side effects and drug resistance. The role of lncRNA NUTM2A-AS1 has been explored in various cancers, but its function in drug-resistant NB progression is unclear. Our study found that NUTM2A-AS1 expression in cisplatin-resistant NB cells increased in a time- and dose-dependent manner. Knockdown of NUTM2A-AS1 significantly improved NB cell sensitivity to cisplatin and inhibited metastatic abilities. Additionally, we identified B7-H3, an immune checkpoint-related protein, as a NUTM2A-AS1-associated protein in NB cells. NUTM2A-AS1 was shown to inhibit the protein degradation of B7-H3. Moreover, NUTM2A-AS1 modulated immune evasion in cisplatin-resistant NB cells through B7-H3. Furthermore, NUTM2A-AS1 expression in cisplatin-resistant NB cells was transactivated by NR1D1. In summary, our results unveil the molecular or biological relationship within the NR1D1/NUTM2A-AS1/B7-H3 axis in NB cells under cisplatin treatment, providing an intriguing avenue for fundamental research into cisplatin-resistant NB.
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Antígenos B7 , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neuroblastoma , RNA Longo não Codificante , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Antígenos B7/metabolismo , Antígenos B7/genética , RNA Longo não Codificante/genética , Cisplatino/farmacologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Evasão da Resposta Imune , Animais , Proteólise/efeitos dos fármacos , CamundongosRESUMO
Prelithiation is an essential technology to compensate for the initial lithium loss of lithium-ion batteries due to the formation of solid electrolyte interphase (SEI) and irreversible structure change. However, the prelithiated materials/electrodes become more reactive with air and electrolyte resulting in unwanted side reactions and contaminations, which makes it difficult for the practical application of prelithiation technology. To address this problem, herein, interphase engineering through a simple solution treatment after chemical prelithiation is proposed to protect the prelithiated electrode. The used solutions are carefully selected, and the composition and nanostructure of the as-formed artificial SEIs are revealed by cryogenic electron microscopy and X-ray photoelectron spectroscopy. The electrochemical evaluation demonstrates the unique merits of this artificial SEI, especially for the fluorinated interphase, which not only enhances the interfacial ion transport but also increases the tolerance of the prelithiated electrode to the air. The treated graphite electrode shows an initial Coulombic efficiency of 129.4%, a high capacity of 170 mAh g-1 at 3 C, and negligible capacity decay after 200 cycles at 1 C. These findings not only provide a facile, universal, and controllable method to construct an artificial SEI but also enlighten the upgrade of battery fabrication and the alternative use of advanced electrolytes.
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Lithium metal has been considered an ideal anode for high-energy rechargeable Li batteries, although its nucleation and growth process remains mysterious, especially at the nanoscale. Here, cryogenic transmission electron microscopy was used to reveal the evolving nanostructure of Li metal deposits at various transient states in the nucleation and growth process, in which a disorder-order phase transition was observed as a function of current density and deposition time. The atomic interaction over wide spatial and temporal scales was depicted by reactive molecular dynamics simulations to assist in understanding the kinetics. Compared to crystalline Li, glassy Li outperforms in electrochemical reversibility, and it has a desired structure for high-energy rechargeable Li batteries. Our findings correlate the crystallinity of the nuclei with the subsequent growth of the nanostructure and morphology, and provide strategies to control and shape the mesostructure of Li metal to achieve high performance in rechargeable Li batteries.
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Lithium metal is an ideal anode material due to its high specific capacity and low redox potential. However, issues such as dendritic growth and low Coulombic efficiency prevent its application in secondary lithium batteries. The use of three-dimensional (3D) porous current collector is an effective strategy to solve these problems. Herein, commercial carbon nanotube (CNT) sponge is used as a 3D current collector for dendrite-free lithium metal deposition to improve the Coulombic efficiency and the cycle stability of the lithium metal batteries. The high specific surface area of the CNT increases the density of the lithium nucleation sites and ensures the uniform lithium deposition while the "pre-lithiation" behavior of the porous CNT enhances its affinity with the deposited lithium. Meanwhile, the lithium plating/stripping on the sponge maintains high Coulombic efficiency and high cycling stability due to the robust structure of graphitic-amorphous carbon composite in the ether-based electrolyte. Our findings exhibit the feasibility of using CNT sponge as a 3D porous current collector for lithium deposition. They shed light on designing and developing advanced current collectors for the lithium metal electrode and will promote the commercialization of the secondary lithium batteries.
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Low storage capacity and poor cycling stability are the main drawbacks of the electrode materials for sodium-ion (Na-ion) batteries, due to the large radius of the Na ion. Here we show that micro-structured molybdenum disulfide (MoS2 ) can exhibit high storage capacity and excellent cycling and rate performances as an anode material for Na-ion batteries by controlling its intercalation depth and optimizing the binder. The former method is to preserve the layered structure of MoS2 , whereas the latter maintains the integrity of the electrode during cycling. A reversible capacity of 90 mAh g(-1) is obtained on a potential plateau feature when less than 0.5 Na per formula unit is intercalated into micro-MoS2 . The fully discharged electrode with sodium alginate (NaAlg) binder delivers a high reversible capacity of 420 mAh g(-1) . Both cells show excellent cycling performance. These findings indicate that metal chalcogenides, for example, MoS2 , can be promising Na-storage materials if their operation potential range and the binder can be appropriately optimized.
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The interaction between the photosensitive antitumour drug, 2(3),9(10),16(17),23(24)-tetra-(((2-aminoethylamino)methyl)phenoxy)phthalocyaninato-zinc(II) (ZnPc) and bovine serum albumin (BSA) has been investigated using various spectroscopic methods. This work may provide some useful information for understanding the interaction mechanism of anticancer drug-albumin binding and gain insight into the biological activity and metabolism of the drug in blood. Based on analysis of the fluorescence spectra, ZnPc could quench the intrinsic fluorescence of BSA and the quenching mechanism was static by forming a ground state complex. Meanwhile, the Stern-Volmer quenching constant (KSV), binding constant (Kb), number of binding sites (n) and thermodynamic parameters were obtained. Results showed that the interaction of ZnPc with BSA occurred spontaneously via hydrogen bond and van der Waal's force. According to Foster's non-radioactive energy transfer theory, the energy transfer from BSA to ZnPc occurred with high possibility. Synchronous fluorescence and circular dichroism (CD) spectra also demonstrated that ZnPc induced the secondary structure of and conformation changes in BSA, especially α helix.
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Indóis/química , Compostos Organometálicos/química , Soroalbumina Bovina/química , Animais , Sítios de Ligação , Bovinos , Dicroísmo Circular , Transferência de Energia , Isoindóis , Estrutura Secundária de Proteína , Termodinâmica , Compostos de ZincoRESUMO
Fast-charging lithium-ion batteries are highly required, especially in reducing the mileage anxiety of the widespread electric vehicles. One of the biggest bottlenecks lies in the sluggish kinetics of the Li+ intercalation into the graphite anode; slow intercalation will lead to lithium metal plating, severe side reactions, and safety concerns. The premise to solve these problems is to fully understand the reaction pathways and rate-determining steps of graphite during fast Li+ intercalation. Herein, we compare the Li+ diffusion through the graphite particle, interface, and electrode, uncover the structure of the lithiated graphite at high current densities, and correlate them with the reaction kinetics and electrochemical performances. It is found that the rate-determining steps are highly dependent on the particle size, interphase property, and electrode configuration. Insufficient Li+ diffusion leads to high polarization, incomplete intercalation, and the coexistence of several staging structures. Interfacial Li+ diffusion and electrode transportation are the main rate-determining steps if the particle size is less than 10 µm. The former is highly dependent on the electrolyte chemistry and can be enhanced by constructing a fluorinated interphase. Our findings enrich the understanding of the graphite structural evolution during rapid Li+ intercalation, decipher the bottleneck for the sluggish reaction kinetics, and provide strategic guidelines to boost the fast-charging performance of graphite anode.
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High-performance Li-ion/metal batteries working at a low temperature (i.e., <-20 °C) are desired but hindered by the sluggish kinetics associated with Li+ transport and charge transfer. Herein, the temperature-dependent Li+ behavior during Li plating is profiled by various characterization techniques, suggesting that Li+ diffusion through the solid electrolyte interface (SEI) layer is the key rate-determining step. Lowering the temperature not only slows down Li+ transport, but also alters the thermodynamic reaction of electrolyte decomposition, resulting in different reaction pathways and forming an SEI layer consisting of intermediate products rich in organic species. Such an SEI layer is metastable and unsuitable for efficient Li+ transport. By tuning the solvation structure of the electrolyte with a lower lowest unoccupied molecular orbital (LUMO) energy level and polar groups, such as fluorinated electrolytes like 1 mol L-1 lithium bis(fluorosulfonyl)imide (LiFSI) in methyl trifluoroacetate (MTFA): fluoroethylene carbonate (FEC) (8:2, weight ratio), an inorganic-rich SEI layer more readily forms, which exhibits enhanced tolerance to a change of working temperature (thermodynamics) and improved Li+ transport (kinetics). Our findings uncover the kinetic bottleneck for Li+ transport at low temperature and provide directions to enhance the reaction kinetics/thermodynamics and low-temperature performance by constructing inorganic-rich interphases.
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The anode plays a critical role relating to the energy density in all-solid-state lithium batteries (ASLBs). Silicon (Si) and lithium (Li) metal are two of the most attractive anodes because of their ultrahigh theoretical capacities. However, most investigations focus on Li metal, leaving the great potential of Si underrated. This work investigates the stability, processability, and cost of Si anodes in ASLBs and compares them with Li metal. Moreover, single-crystal LiNi0.8 Mn0.1 Co0.1 O2 is stabilized with lithium silicate (Li2 SiOx ) through a scalable sol-gel method. ASLBs with a cell-level energy density of 285 Wh kg-1 are obtained by sandwiching the Si anode, the thin sulfide solid-state electrolyte membrane, and the interface stabilized LiNi0.8 Mn0.1 Co0.1 O2 . The full cell delivers a high capacity of 145 mAh g-1 at C/3 and maintains stability for 1000 cycles. This work inspires commercialization of ASLBs on a large scale with exciting manufacturing lines for large-scale, safe, and economical energy storage.
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The emerging cryogenic electron microscopy (cryo-EM) has demonstrated its power and essential role in probing the beam-sensitive battery materials and delivering new insights. With the increasing interest in cryo-EM for battery materials and interfaces, herein we provide the strategies of obtaining fresh and native structural information with minimal artifacts, including sample preparation, transferring, imaging, and data interpretation. We summarize the recent achievements enabled by cryo-EM and point out some unsolved/potential questions in terms of the bulk materials, solid-solid interface, and solid-liquid interfaces of batteries. Finally, we conclude with perspectives on the future developments and applications of cryo-EM in battery materials and interfaces.
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This study is to elucidate the functions of miR-100 in hepatocellular carcinoma progression and to explore the underlying mechanisms. Expression levels of miR-100 in normal-cancer hepatocellular carcinoma tissues were measured using quantitative real-time PCR (qRT-PCR). The invasive and proliferative abilities of hepatocellular carcinoma cell lines transfected with mimic-NC or mimic-miR-100 were measured using transwell, CCK-8, and colony formation assays. The binding sites between CXCR7 and miR-100 were determined using luciferase reporter assays. The correlation of CXCR7 and miR-100 in hepatocellular carcinoma progression was further confirmed by cotransfection assays. Our results showed that miR-100 was significantly lower expressed in hepatocellular carcinoma tissues and negatively associated with CXCR7 expression. Cell functional assays' results found that upregulation of miR-100 inhibited the proliferative, invasive, and migrative abilities in hepatocellular carcinoma cells. Luciferase reporter assay suggested that CXCR7 mRNA and miR-100 bound one another. Increasing CXCR7 expression reversed the inhibitive effects of upregulated miR-100 in hepatocellular carcinoma cells. Further study showed that miR-100/CXCR7 played a role in hepatocellular carcinoma progression by regulating metalloproteinase-2 (MMP2) and vascular endothelial growth factor (VEGF). Conclusively, miR-100 exerts antitumor effects on hepatocellular carcinoma. Overexpression of miR-100 attenuates the invasive and proliferative abilities of hepatocellular carcinoma cells by targeting CXCR7.
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Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/metabolismo , Receptores CXCR/genética , Animais , Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/cirurgia , Estudos de Casos e Controles , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células Hep G2 , Hepatectomia , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Camundongos , Invasividade Neoplásica/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Recent works into sulfide-type solid electrolyte materials have attracted much attention among the battery community. Specifically, the oxidative decomposition of phosphorus and sulfur based solid state electrolyte has been considered one of the main hurdles towards practical application. Here we demonstrate that this phenomenon can be leveraged when lithium thiophosphate is applied as an electrochemically "switched-on" functional redox mediator-generator for the activation of commercial bulk lithium sulfide at up to 70 wt.% lithium sulfide electrode content. X-ray adsorption near-edge spectroscopy coupled with electrochemical impedance spectroscopy and Raman indicate a catalytic effect of generated redox mediators on the first charge of lithium sulfide. In contrast to pre-solvated redox mediator species, this design decouples the lithium sulfide activation process from the constraints of low electrolyte content cell operation stemming from pre-solvated redox mediators. Reasonable performance is demonstrated at strict testing conditions.
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The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of I. subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. subelongatus from all the six tested populations responded strongly to (S)-(-)-ipsenol (100% detection; 0.35-0.73 mV) in gas chromatography (GC)-electroantennographic detection (EAD) analyses, while its antipode, (R)-(+)-ipsenol was antennally inactive. I. subelongatus populations varied in their responses to (R)-(-)- and (S)-(+)-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that (S)-(-)-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of I. subelongatus, whereas (S)-(+)-ipsdienol was inactive alone. Adding (S)-(+)-ipsdienol to (S)-(-)-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, (S)-(+)-ipsdienol showed a strong synergistic effect on (S)-(-)-ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mitochondrial haplotypes were found among the 13 populations (intraspecific nucleotide divergence, 0.1%-1.1%). Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend of racemic ipsenol and (S)-(+)-ipsdienol might have a potential for monitoring or even mass-trapping of I. subelongatus across northeastern China, even though some populations only use (S)-(-)-ipsenol alone as their active pheromone component.
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Álcoois/farmacologia , Monoterpenos/farmacologia , Octanóis/farmacologia , Feromônios/farmacologia , Gorgulhos/genética , Monoterpenos Acíclicos , Animais , Antenas de Artrópodes/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , China , DNA Mitocondrial/genética , Feminino , Masculino , Feromônios/genética , Gorgulhos/efeitos dos fármacosRESUMO
Different guest species, including amorphous carbon, polyvinyl pyrrolidone (PVP), ethylene diaminetrimolybdate (EDA) derived small molecules, have been successfully intercalated into a nano-scaled MoS2 (nano-MoS2). These guest species bridge the MoS2 slabs through chemical bonding and their host-guest interactions influence the structure and electrochemical performance of the nano-MoS2. When applied in lithium (Li) and sodium (Na) ion batteries, these MoS2 nanostructures exhibit distinguished intercalation thermodynamics and cycling performances. These findings shed light on the design of MoS2 nanostructures and other two-dimensional layer-structured materials.
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In this paper, to minimize the effects of different structure, three alanine-based zinc phthalocyanines (Pcs) of differing charges were engineered and synthesized with the same basic structure. On this premise, the relationship between nature of charge and photodynamic activity was studied. Besides, further verification and explanation of some inconsistent results were also carried out. The results showed that charge can influence the aggregation state, singlet oxygen generation ability and cellular uptake of Pcs, thereby affecting their photodynamic activity. In addition, the biomolecules inside cells may interact with Pcs of differing charges, which can also influence the aggregation state and singlet oxygen generation of the Pcs, and then influence the relationship between nature of charge and photodynamic activity.