Competitive Coordination of Sodium Ions for High-Voltage Sodium Metal Batteries with Fast Reaction Speed.

The unstable electrode-electrolyte interface and the narrow electrochemical window of normal electrolytes hinder the potential application of high-voltage sodium metal batteries. These problems are actually related to the solvation structure of the electrolyte, which is determined by the competition between cations coordinated with anions or solvent molecules. Herein, we design an electrolyte incorporating ethyl (2,2,2-trifluoroethyl) carbonate and fluoroethylene carbonate, which facilitates a pronounced level of cation-anion coordination within the solvation sheath by enthalpy changes to reduce the overall coordination of cation-solvents and increase sensitivity to salt concentration. Such an electrolyte regulated by competitive coordination leads to highly reversible sodium plating/stripping with extended cycle life and a high Coulombic efficiency of 98.0%, which is the highest reported so far in Na||Cu cells with ester-based electrolytes. Moreover, 4.5 V high-voltage Na||Na3V2(PO4)2F3 cells exhibit a high rate capability up to 20 C and an impressive cycling stability with an 87.1% capacity retention after 250 cycles with limited Na. The proposed strategy of solvation structure modification by regulating the competitive coordination of the cation provides a new direction to achieve stable sodium metal batteries with high energy density and can be further extended to other battery systems by controlling enthalpy changes of the solvation structure.

α-Lipoic acid improves mitochondrial biogenesis and dynamics by enhancing antioxidant and inhibiting Wnt/Ca2+ pathway to relieve fluoride-induced hepatotoxic injury.

Fluoride (F), widely present in water and food, poses a serious threat to liver health, and oxidative damage and mitochondrial damage are its main causes. As a natural mitochondrial protector and antioxidant, α-lipoic acid (ALA)'s alleviating effect on fluorosis liver injury and its underlying mechanism are still unclear. Therefore, this study established a fluorosis ALA intervention mice model to explore the mechanism of mitochondrial biogenesis, mitochondrial dynamics, and Wnt/Ca2+ pathway in ALA attenuating fluorosis liver injury. The results showed that ALA mitigated F-induced weight loss, hepatic structural and functional damage, hepatocytes mitochondrial damage, and decreased antioxidant levels. However, ALA did not reduce F accumulation in the femur. Further mRNA and protein detection results showed that F increased the expression levels of key genes in the mitochondrial fission (Drp1, Mff, and Fis1), mitophagy (Parkin, Pink1, and Prdx3), Wnt/Ca2+ pathway (Wnt5a and CaMK2), and rised the number and intensity of fluorescent spots of Drp1, but decreased the expression levels of key genes in the mitochondrial biogenesis (Sirt1, Sirt3, and PGC-1α) and fusion (OPA1, Mfn2, and Mfn1), and reduced the number and intensity of fluorescent spots of PGC-1α in the liver. However, the intervention of ALA relieved the F-induced changes in the expressions of the above genes. In conclusion, ALA mitigated F-induced hepatic injury through enhancing antioxidant capacity and inhibiting Wnt/Ca2+ pathway to improve mitochondrial biogenesis and dynamics disturbance. This study further reveals the hepatotoxic mechanism of F and the protective mechanism of ALA, and provides a theoretical basis for ALA as a potential preventive and palliative agent for F-induced hepatotoxic injury.

Dopant- and Surfactant-Tuned Electrode-Electrolyte Interface Enabling Efficient Alkynol Semi-Hydrogenation.

Electrochemical alkynol semi-hydrogenation has emerged as a sustainable and environmentally benign route for the production of high-value alkenols, featuring water as the hydrogen source instead of H2. It is highly challenging to design the electrode-electrolyte interface with efficient electrocatalysts and their matched electrolytes to break the selectivity-activity stereotype. Here, boron-doped Pd catalysts (PdB) and surfactant-modified interface are proposed to enable the simultaneous increase in alkenol selectivity and alkynol conversion. Typically, compared to pure Pd and commercial Pd/C catalysts, the PdB catalyst achieves both higher turnover frequency (139.8 h-1) and specific selectivity (above 90%) for the semi-hydrogenation of 2-methyl-3-butyn-2-ol (MBY). Quaternary ammonium cationic surfactants that are employed as electrolyte additives are assembled at the electrified interface in response to applied bias potential, establishing an interfacial microenvironment that can facilitate alkynol transfer and hinder water transfer suitably. Eventually the hydrogen evolution reaction is inhibited and alkynol semi-hydrogenation is promoted, without inducing the decrease of alkenol selectivity. This work offers a distinct perspective on creating a suitable electrode-electrolyte interface for electrosynthesis.

Tunable Ordered Nanostructured Phases by Co-assembly of Amphiphilic Polyoxometalates and Pluronic Block Copolymers.

The assembly of polyoxometalate (POM) metal-oxygen clusters into ordered nanostructures is attracting a growing interest for catalytic and sensing applications. However, assembly of ordered nanostructured POMs from solution can be impaired by aggregation, and the structural diversity is poorly understood. Here, we present a time-resolved small-angle X-ray scattering (SAXS) study of the co-assembly in aqueous solutions of amphiphilic organo-functionalized Wells-Dawson-type POMs with a Pluronic block copolymer over a wide concentration range in levitating droplets. SAXS analysis revealed the formation and subsequent transformation with increasing concentration of large vesicles, a lamellar phase, a mixture of two cubic phases that evolved into one dominating cubic phase, and eventually a hexagonal phase formed at concentrations above 110 mM. The structural versatility of co-assembled amphiphilic POMs and Pluronic block copolymers was supported by dissipative particle dynamics simulations and cryo-TEM.

Effects of skin flap grafting combined with vacuum sealing drainage on ulcer area, pain level, and serum inflammation in diabetic foot patients.

OBJECTIVE: To study the effects of skin flap grafting combined with vacuum sealing drainage (VSD) on ulcer area, pain level and serum inflammation in patients with diabetic foot (DF). METHODS: In this retrospective study, 121 patients with DF who were treated in the Affiliated Hospital of Xinyang Vocational and Technical College between April 2018 and April 2022 were included as study subjects, including 50 cases receiving skin flap grafting (control group) and 71 cases receiving skin flap grafting combined with VSD (research group). Information on clinical efficacy, survival rate of the grafted flap, amputation and complications, ulcer area, rehabilitation (granulation tissue formation time, ulcer wound healing time), pain level (Visual Analogue Scale [VAS]), and serum inflammatory factors (interleukin [IL]-6, tumor necrosis factor [TNF]-α, and C-reactive protein [CRP]) were collected for comparative analyses. Univariate and multivariate analyses were conducted to screen the risk factors for patients' prognosis. RESULTS: The overall response rate and the survival rate of the grafted flap in the research group were markedly higher compared with the control group, while the amputation rate was significantly lower (all P<0.05). Besides, the research group exhibited an evidently smaller post-treatment ulcer area, lower VAS, IL-6, TNF-α and CRP levels, and shorter granulation tissue formation time and ulcer wound healing time than the control group (all P<0.05). Neither group of patients experienced significant complications. The use of skin flap grafting + VSD was a protective factor for postoperative outcome. CONCLUSIONS: Skin flap grafting combined with VSD is effective in treating DF patients, which can validly reduce ulcer area and inhibit serum inflammation after treatment, thus accelerating rehabilitation.

Indefinite Graphene Nanocavities with Ultra-Compressed Mode Volumes.

Explorations of indefinite nanocavities have attracted surging interest in the past few years as such cavities enable light confinement to exceptionally small dimensions, relying on the hyperbolic dispersion of their consisting medium. Here, we propose and study indefinite graphene nanocavities, which support ultra-compressed mode volumes with confinement factors up to 109. Moreover, the nanocavities we propose manifest anomalous scaling laws of resonances and can be effectively excited from the far field. The indefinite graphene cavities, based on low dimensional materials, present a novel rout to squeeze light down to the nanoscale, rendering a more versatile platform for investigations into ultra-strong light-matter interactions at mid-infrared to terahertz spectral ranges.

Multiomics Analysis Revealed the Molecular Mechanism of miRNAs in Fluoride-Induced Hepatic Glucose and Lipid Metabolism Disorders.

Fluoride-induced liver injury seriously endangers human and animal health and animal food safety, but the underlying mechanism remains unclear. This study aims to explore the mechanism of miRNAs in fluoride-induced hepatic glycolipid metabolism disorders. C57 male mice were used to establish the fluorosis model (22.62 mg/L F-, 12 weeks). The results indicated that fluoride increased fluoride levels, impaired the structure and function, and disrupted the glycolipid metabolism in the liver. Furthermore, the sequencing results showed that fluoride exposure resulted in the differential expression of 35 miRNAs and 480 mRNAs, of which 23 miRNAs were related to glycolipid metabolism. miRNA-mRNA network analyses and RT-PCR revealed that miRNAs mediated fluoride-induced disturbances in the hepatic glycolipid metabolism. Its possible mechanism was to regulate the insulin pathway, PPAR pathway, and FOXO pathway, which in turn affected the bile secretion, the metabolic processes of glucose, the decomposition of lipids, and the synthesis of unsaturated fatty acids in the liver. This study provides a theoretical basis for miRNAs as diagnostic indicators and target drugs for the treatment of fluoride-induced liver injury.

High-Efficiency CO2 /N2 Separation Enabled by Rotation of Electrostatically Anchored Flexible Ligands in Metal-Organic Framework.

Metal organic frameworks (MOF) are of great potential for molecular separation, but the ligand rotation flexibility makes them remain challenging in the construction of fixed nanochannels for precise sieving. Here we report an electrostatic-anchoring strategy to fix the rotation of 2-methylimidazole (2-MIM) ligand in ZIF-8. Electrostatic inducer trifluoroacetate anchored at and blocked the six-membered windows of ZIF-8, and meanwhile induced the positive 2-MIM rotated from initial 49° to 68°, thus opening neighbored four-membered windows with a constant size of 3.4 Å. The obtained ZIF-8 significantly enhanced the CO2 /N2 adsorption selectivity from 14.02 to 332.86. Further membrane-based separation exhibited an outstanding CO2 /N2 selectivity of up to 137 with a desired permeability of 286 Barrer, which exceeded the 2019 upper bound. This strategy provides a new inspiration for fixing the ligand rotation in soft MOF for desired precise molecular sieving.

Suppressing Vanadium Dissolution in "Water-in-Salt" Electrolytes for 3.2 V Aqueous Sodium-Ion Pseudocapacitors.

Low-cost sodium-ion-based electrochemical energy storage devices, especially vanadium-based sodium-ion pseudocapacitors, are receiving increasing attention. However, the inevitable dissolution of vanadium in aqueous electrolytes usually leads to poor cycling stability and a narrow electrochemical stability window (ESW). In this study, we prepared layered (NH4)2V10O25·8H2O with a hierarchical flower-like structure and an ultralarge layer spacing and evaluated its potential as a sodium-ion pseudocapacitive material. Ex situ X-ray diffraction (XRD) measurement and kinetic analysis demonstrate the reversible intercalation and deintercalation of Na+ in (NH4)2V10O25·8H2O in NaClO4 electrolytes. Significantly improved durability and a large voltage window of 3.2 V are achieved in the high-concentration NaClO4 electrolyte. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis and molecular dynamics (MD) simulations reveal that the dissolution of vanadium in the high-concentration NaClO4 electrolyte can be effectively suppressed. An asymmetric sodium-ion capacitor with a wide voltage window of 3.2 V was successfully assembled, and it delivered a high energy density of 53.1 Wh kg-1 at a power density of 3.2 kW kg-1.

Electrostatic-Induced Crystal-Rearrangement of Porous Organic Cage Membrane for CO2 Capture.

Porous Organic Cages (POCs) with tunable tailoring chemistry properties and polymer-like processing conditions are of great potential for molecular selective membranes, but it remains challenging in the assembly of high crystalline POCs with regular nanochannels for effective molecular sieving. Here we report an electrostatic-induced crystal-rearrangement strategy for the design of a POC membrane with heterostructure. Due to electrostatic attraction, ionic liquid molecules induced cage molecules to rearrange into a sub-10 nm uniform and defect-free crystal layer, which displayed competitive CO2 separation performance. The optimized hetero-structured membrane exhibited an attractive CO2 /N2 separation selectivity of over 130, which was superior to the state-of-the-art membranes, accompanied with excellent long-term and thermal shock stability. This strategy provides a new inspiration for the preparation of crystal-rearranged membranes with regular channels for gas molecule sieving.

Millimeter-scale ultrathin suspended metasurface integrated high-finesse optomechanical cavity.

A typical optomechanical system is a cavity with one movable mirror and one fixed mirror. However, this configuration has been considered incapable of integrating sensitive mechanical elements while maintaining high cavity finesse. Although the membrane-in-the-middle solution seems to be able to overcome this contradiction, it introduces additional components that will lead to unexpected insertion loss, resulting in reduced cavity quality. Here we propose a Fabry-Perot optomechanical cavity composed of an ultrathin suspended Si3N4 metasurface and a fixed Bragg grating mirror, with a measured finesse up to 1100. Transmission loss of this cavity is very low as the reflectivity of this suspended metasurface tends to unity around 1550 nm. Meanwhile, the metasurface has a millimeter-scale transverse dimension and a thickness of only 110 nm, which guarantees a sensitive mechanical response and low cavity diffraction loss. Our metasurface-based high-finesse optomechanical cavity has a compact structure, which facilitates the development of quantum and integrated optomechanical devices.

Silicon nitride waveguides with directly grown WS2 for efficient second-harmonic generation.

Different functions can be directly realized by silicon (Si) in integrated electronic circuits. Although Si and silicon nitride (Si3N4) photonics have shown great potential in integrated optoelectronic devices, different functions, such as light generation, transparency for guided light, and light detection, cannot be simultaneously achieved only by Si or Si3N4. Second-order nonlinearity is another optical property they do not possess due to their centrosymmetric properties. Several kinds of 2D materials emerged recently and were transferred to specified photonic devices aimed at improving their nonlinear performance. However, the transferring methods are time-consuming, unable to achieve large-scale production, and will inevitably cause materials damage and introduce impurities at the interface. Herein, we demonstrate the direct growth of large-area homogeneous monolayer WS2via a physical vapor deposition method onto Si3N4 waveguides. The WS2 growth can be controlled mainly along the Si3N4 waveguides and the waveguides show an obvious enhancement of second-harmonic generation with the elongated WS2 coverage. The direct growth of WS2 endows Si3N4 integrated photonics with new nonlinear optical properties. As an alternative method of transferring 2D materials, the method we present here is compatible with large-scale integrated photonic fabrication, which lays the foundation for on-chip integrated optical fabrication and applications.

A suspended metasurface achieves complete light absorption: a 50 nm-thick optical nanomicrophone.

Considerably subtle vibrations can be detected by light signals. Commonly, this is achieved based on the phase change of light that can be attributed to the vibration of a movable mirror, which has been used in gravitational wave detection. For a homogeneous dielectric membrane, the thinner the membrane, the greater the membrane vibration amplitude will be with respect to the sound pressure. However, if the membrane is too thin, most of the light will transmit through the membrane and the sensitivity will be reduced. To resolve this contradiction, we have developed a metasurface membrane with a thickness of only 50 nm but a considerably high reflectivity. This membrane is integrated with a 100-nm-thick gold membrane to form a cavity that can achieve perfect absorption of light. The vibration of the metasurface, which records the sound wave information, can change the light absorption. The noise equivalent pressure of the proposed structure is several orders lower than those of the recently reported optoacoustic detectors, and the alternating current signal response can be enhanced by approximately 1500 times compared with that of a membrane without a metasurface. The integration of nanomechanical oscillators and ultrathin membranes with a metasurface may facilitate future ultrasensitive sound and ultrasonic detection and benefit optomechanic design.