Conjugated polymeric molecules have been heralded as promising electrode materials for the next-generation energy-storage technologies owing to their chemical flexibility at the molecular level, ...environmental benefit, and cost advantage. However, before any practical implementation takes place, the low capacity, poor structural stability, and sluggish ion/electron diffusion kinetics remain the obstacles that have to be overcome. Here, we report the synthesis of a few-layered two-dimensional covalent organic framework trapped by carbon nanotubes as the anode of lithium-ion batteries. Remarkably, upon activation, this organic electrode delivers a large reversible capacity of 1536 mAh g
and can sustain 500 cycles at 100 mA g
. Aided by theoretical calculations and electrochemical probing of the electrochemical behavior at different stages of cycling, the storage mechanism is revealed to be governed by 14-electron redox chemistry for a covalent organic framework monomer with one lithium ion per C=N group and six lithium ions per benzene ring. This work may pave the way to the development of high-capacity electrodes for organic rechargeable batteries.
Yolk–shell NiO microspheres are modified by two types of functionalized graphene quantum dots (denoted as NiO/GQDs) via a facile solvothermal treatment. The modification of GQDs on the surface of NiO ...greatly boosts the stability of the NiO/GQD electrode during long‐term cycling. Specifically, the NiO with carboxyl‐functionalized GQDs (NiO/GQDsCOOH) exhibits better performances than NiO with amino‐functionalized GQDs (NiO/GQDsNH2). It delivers a capacity of ≈1081 mAh g−1 (NiO contribution: ≈1182 mAh g−1) after 250 cycles at 0.1 A g−1. In comparison, NiO/GQDsNH2 electrode holds ≈834 mAh g−1 of capacity, while the bald NiO exhibits an obvious decline in capacity with ≈396 mAh g−1 retained after cycling. Except for the yolk–shell and mesoporous merits, the superior performances of the NiO/GQD electrode are mainly ascribed to the assistance of GQDs. The GQD modification can support as a buffer alleviating the volume change, improve the electronic conductivity, and act as a reservoir for electrolytes to facilitate the transportation of Li+. Moreover, the enrichment of carboxyl/amino groups on GQDs can further donate more active sites for the diffusion of Li+ and facilitate the electrochemical redox kinetics of the electrode, thus together leading to the superior lithium storage performance.
Metal–organic frameworks–derived yolk–shell NiO microspheres are modified by two types of functionalized graphene quantum dots (NiO/GQDs) via a facile solvothermal treatment. The modification of GQDs on the surface of NiO greatly boosts the stability of the NiO/GQD electrode with a superior lithium storage performance during long‐term cycling.
The existence of breast cancer stem cells (BCSCs) is a major reason underlying cancer metastasis and recurrence after chemotherapy and radiotherapy. Targeting BCSCs may ameliorate breast cancer ...relapse and therapy resistance. Here we report that expression of the pseudokinase Tribble 3 (TRIB3) positively associates with breast cancer stemness and progression. Elevated TRIB3 expression supports BCSCs by interacting with AKT to interfere with the FOXO1-AKT interaction and suppress FOXO1 phosphorylation, ubiquitination, and degradation by E3 ligases SKP2 and NEDD4L. The accumulated FOXO1 promotes transcriptional expression of SOX2, a transcriptional factor for cancer stemness, which in turn, activates FOXO1 transcription and forms a positive regulatory loop. Disturbing the TRIB3-AKT interaction suppresses BCSCs by accelerating FOXO1 degradation and reducing SOX2 expression in mouse models of breast cancer. Our study provides insights into breast cancer development and confers a potential therapeutic strategy against TRIB3-overexpressed breast cancer.
In this work, hydroxyl‐functionalized Mo2C‐based MXene nanosheets are synthesized by facilely removing the Sn layer of Mo2SnC. The hydroxyl‐functionalized surface of Mo2C suppresses the shuttle ...effect of lithium polysulfides (LiPSs) through strong interaction between Mo atoms on the MXenes surface and LiPSs. Carbon nanotubes (CNTs) are further introduced into Mo2C phase to enlarge the specific surface area of the composite, improve its electronic conductivity, and alleviate the volume change during discharging/charging. The strong surface‐bound sulfur in the hierarchical Mo2C‐CNTs host can lead to a superior electrochemical performance in lithium–sulfur batteries. A large reversible capacity of ≈925 mAh g−1 is observed after 250 cycles at a current density of 0.1 C (1 C = 1675 mAh g−1) with good rate capability. Notably, the electrodes with high loading amounts of sulfur can also deliver good electrochemical performances, i.e., initial reversible capacities of ≈1314 mAh g−1 (2.4 mAh cm−2), ≈1068 mAh g−1 (3.7 mAh cm−2), and ≈959 mAh g−1 (5.3 mAh cm−2) at various areal loading amounts of sulfur (1.8, 3.5, and 5.6 mg cm−2) are also observed, respectively.
Mo2C‐based MXene nanosheets composited with carbon nanotubes are synthesized and used as sulfur host in lithium–sulfur (Li–S) batteries. The hydroxyl‐functionalized surface of Mo2C suppresses the shuttle effect of lithium polysulfides (LiPSs) through strong interaction between Mo atoms on the MXenes surface and LiPSs, leading to a superior electrochemical performance in Li–S batteries.
Polycystic ovary syndrome (PCOS) is one of the most prevalent reproductive disorders in women worldwide. Despite rigorous research, the exact molecular mechanism that governs PCOS pathogenesis ...remains unclear. To investigate the potential roles of circular RNAs (circRNAs), this study sequenced ribosomal RNA‐depleted total RNA from exosomes of follicle fluids obtained from PCOS patients using non‐PCOS samples as controls. Bioinformatic analysis identified 167 upregulated and 245 downregulated circRNAs from a total of 16,771 detected candidates. Functional analysis suggests that pathways related to bacterial infection, associated chronic inflammation, and oxidative stress could be targeted by the differential circRNAs in PCOS patients. The obtained sequencing results were further validated by quantitative reverse‐transcription polymerase chain reaction and a circRNA–microRNA interaction network was constructed. The obtained results provide a valuable addition to the published studies on the mechanism of PCOS pathogenesis by revealing a wide variety of new circRNAs, miRNA, and gene targets that merit further investigation.
We have provided the first study on the dysregulation of circRNAs in patients with polycystic ovary syndrome using RNA sequencing and bioinformatic analysis. We identified over 16,771 differentially expressed circRNA candidates, many of which showed implication in pathological processes such as bacterial infection, oxidative stress, and autophagy.
Nationwide nonpharmaceutical interventions (NPIs) have been effective at mitigating the spread of the novel coronavirus disease (COVID-19), but their broad impact on other diseases remains ...under-investigated. Here we report an ecological analysis comparing the incidence of 31 major notifiable infectious diseases in China in 2020 to the average level during 2014-2019, controlling for temporal phases defined by NPI intensity levels. Respiratory diseases and gastrointestinal or enteroviral diseases declined more than sexually transmitted or bloodborne diseases and vector-borne or zoonotic diseases. Early pandemic phases with more stringent NPIs were associated with greater reductions in disease incidence. Non-respiratory diseases, such as hand, foot and mouth disease, rebounded substantially towards the end of the year 2020 as the NPIs were relaxed. Statistical modeling analyses confirm that strong NPIs were associated with a broad mitigation effect on communicable diseases, but resurgence of non-respiratory diseases should be expected when the NPIs, especially restrictions of human movement and gathering, become less stringent.
The metal–organic-framework (MOF) approach is demonstrated as an effective strategy for the morphology evolution control of MIL-53(Fe) with assistance of microwave irradiation. Owing to the ...homogeneous nucleation offered by microwave irradiation and confined porosity and skeleton by MOF templates, various porous Fe2O3 nanostructures including spindle, concave octahedron, solid octahedron, yolk–shell octahedron, and nanorod with porosity control are derived by simply adjusting the irradiation time. The formation mechanism for the MOF precursors and their derived iron oxides with morphology control is investigated. The main product of the mesoporous yolk–shell octahedron-in-octahedron Fe2O3 nanostructure is also found to be a promising anode material for lithium-ion batteries due to its excellent Li-storage performance. It can deliver a reversible larger-than-theoretical capacity of 1176 mAh g–1 after 200 cycles at 100 mA g–1 and good high-rate performance (744 mAh g–1 after 500 cycles at 1 A g–1).
Detrimental dendritic lithium (Li) growth, infinite volume expansion of Li deposition and inevitable excess electrolyte consumption have always impeded the successful application of Li metal anodes. ...Herein, a unique lithiophilic vertical cactus‐like framework (LVCF) derived from a Zn/Cu‐based coordination polymer through in situ chemical etching of Cu foam is proposed to enhance the safety and electrochemical performance of Li metal anodes. An ingenious strategy of releasing Cu ions from Cu foam in the presence of organic ligands is implemented successfully to achieve the coordination polymer precursor, resulting in the coexistence of massive lithiophilic nitrogen‐containing functional groups, ZnO quantum dots and in situ grown carbon nanotubes (CNTs) in the LVCF, which is beneficial to avoiding the generation of harmful Li dendrites. Benefiting from the positive effects of the improved lithiophilicity, decreased local current density and relieved volume expansion, LVCF delivers an ultrastable Coulombic efficiency of 98.6% for 600 cycles at 1 mA cm–2 and an improved cycling lifespan of 1800 h for symmetric cells. Full cells comprising LVCF@Li anodes and LiFePO4 cathodes can deliver an ultrahigh capacity of 101.8 mAh g–1 (capacity retention ratio: 77.9%) after 900 cycles at 1 C and excellent rate performance.
A 3D free‐standing and lithiophilic vertical cactus‐like framework, commercial Cu foam covered by an annealed Zn/Cu‐based precursor, is proposed as the current collector of Li metal anode. Massive lithiophilic sites (ZnO quantum dots and nitrogen containing groups) and in situ grown carbon nanotubes play a significant role in the suppression of Li dendrites.
Covalent organic framework, as an emerging porous nano‐frame structure with pre‐designed structure and custom properties, has been demonstrated as a prospective electrode for rechargeable Li‐ion ...batteries. For improving the reversible capacity and long‐term cycle stability of COF materials, we propose a GQDs modified COF material (COF‐GQDs) and apply it as the anode for LIBs for the first time. This COF‐GQDs electrode delivers enhanced long‐term cycling performance with a large capacity of ∼820 mAh g−1 after 300 cycles at 100 mA g−1 and an improved rate performance. The enhanced lithium‐storage performance, in terms of obvious‐shortened activation process and high reversible capacities, can be attributed to the modification of carboxyl GQDs, which would activate more active sites (activated C=C groups from benzene rings) for lithium‐storage, and provide fast lithium‐ion transportation kinetic. Besides, the decreased interphase resistance, enhanced electronic conductivity, and prevented aggregation of needle‐flake COF structure, originated from the addition of GQDs, which lead to the enhanced improved cycling stability of the COF‐GQDs electrode. This manuscript can promote the further exploration on the design of COF‐related materials with modification of functionalized carbonaceous materials to achieve enhanced lithium‐storage properties for next‐generation energy storage.
Functionalized graphene quantum dots (GQDs) modified dioxin‐linked covalent organic frameworks (COF) are fabricated and applied as anode material of lithium‐ion battery for the first time. The modification of carboxyl GQDs leads to more active sites, fast lithium‐ion transportation kinetics, and enhanced electronic conductivity, resulting in enhanced lithium‐storage properties for the graphene quantum dots modified covalent organic frameworks (COF‐GQDs) electrode
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