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关键词： Asymmetric supercapacitor devices   Ion transport enhancement   Lithium-substituted cobalt ferrite   Magnetic field-assisted supercapacitors   Magneto-electrochemical coupling   Spinel ferrite electrodes  

摘要： Supercapacitors are essential energy-storage devices because of their high-power density, rapid charge/discharge capabilities, and long cycle life. Magnetic field-assisted supercapacitors offer a promising method to improve charge transport and electrochemical performance. Among others, spinel ferrites possess intrinsic magnetic moments, making them promising electrode candidates. This study investigates how non-stoichiometric lithium substitution affects the structural, magnetic, and electrochemical properties of cobalt ferrite (CoFe₂O₄) to enhance its suitability for supercapacitor applications. The substitution of Li⁺ ions for Co²⁺ ions alters the spinel framework, leading to significant magnetic changes. Magnetic measurements showed that the saturation magnetization decreased gradually with increasing lithium content, while the Co_0.25Li_0.75Fe₂O4 composition exhibited a significant reduction in coercivity, confirming its soft-magnetic behavior. The observed effects are linked to reduced particle size (≈28 nm) and the modulation of exchange interactions and magnetic anisotropy. The supercapacitive performance was systematically investigated in both three- and two-electrode configurations in Li₂SO₄. A remarkable improvement in capacitance was achieved in the presence of an external magnetic field, with Co ferrite delivering 550 F/g, compared to 255 F/g without the field. Moreover, Asymmetric supercapacitors utilizing Co ferrite for the positive electrode and graphene oxide nanoribbons (GONRs) for the negative electrode demonstrated good cycling stability, maintaining 85–95% of their capacitance after 10,000 cycles, with Coulombic efficiencies of 96–97%, demonstrating stable long-term performance at a high current density of 10 A/g. The devices also functioned efficiently across a wide potential range of 1.9 V. The results clearly show that lithium-substituted

关键词： Bis(2-amino-3-nitro-4-methylpyridinium) 1,5-naphthalenedisulfonate dihydrate   Crystal structure   DFT   Vibrational spectroscopy  

摘要： Single crystals of Bis(2-amino-3-nitro-4-methylpyridinium) 1,5-naphthalenedisulfonate Dihydrate (hereafter named as crystal I) were grown by the slow evaporation technique. Single crystal X-ray diffraction confirms a monoclinic system with centrosymmetric space group P2₁/n. Vibrational spectroscopic studies identify the characteristic functional groups present in the crystal. Hirshfeld surface analysis reveals that H···H (37.6%) and O···H/H···O (31.7%) interactions dominate the crystal packing, emphasizing the role of hydrogen bonding and van der Waals forces. Molecular electrostatic potential mapping highlights electron-rich regions over NO₂ and SO₃ groups and electron-deficient regions around NH₂ hydrogen atoms. TD-DFT calculations indicate weak π→π* and n→π* transitions in the 405–663 nm range with a HOMO–LUMO gap of 3.3097 eV, reflecting the electronic stability of the system. The NBO analysis shows a highest stabilization energy of 392.71 kcal/mol between the lone pair of one atom LP(1)N47 & LP(1)N25 to the antibonding orbital of another atom LP*(1)H48 and LP*(1)H26 respectively followed by next highest stabilization energy of 190.97 kcal/mol for the transition LP(1)C52 to π*(N47-C54) & LP(1)C30 to π*(N25-C32) respectively. The total hyperpolarizability of crystal I is 0.1237 × 10 ̶ 31 e.s.u which indicates that the first-order hyperpolarizability is 3.3 times that of urea. Natural bond orbital, ELF, LOL, and RDG-NCI analyses further confirm the presence of strong covalent bonding along with weak noncovalent interactions. Overall, the combined experimental and theoretical investigations provide a comprehensive understanding of the structural and electronic features of crystal I.

关键词： Dirac equation   Dirac semimetals   Finite-differences   Numerical scheme   Runge-Kutta methods   Symplectic integrator   Tilted Dirac cones  

摘要： Owing to their increased electron mobility compared to conventional semiconductors, three-dimensional (3D) Dirac semimetals are considered to be promising candidates for integration into next-generation electronic devices. In these materials, the low-energy dynamics of the charge carriers are governed by an effective tilted Dirac equation, in which a mass term appears when strain is applied to the crystal lattice. In this work, we present a novel finite-difference scheme capable of numerically solving the 3D tilted Dirac equation in the time domain. The method employs fourth-order accurate finite differences to discretize the spatial derivatives and a symplectic partitioned Runge-Kutta (PRK) integrator to propagate the Dirac spinor in time. To this end, a careful separation of the complex-valued spinor into two real-valued parts is performed to ensure compatibility with the PRK technique. Moreover, to account for the additional term in the Hamiltonian arising from the tilt of the Dirac cones, fourth-order accurate averaging operators are incorporated into the spatial discretization, without compromising the key properties of the scheme. The resulting numerical method is explicit and is shown to conserve the norm, energy, and momentum of the system. Its stability condition is derived, and the numerical dispersion is thoroughly investigated. Illustrative numerical experiments are performed, demonstrating the excellent properties of the proposed method and its applicability to a more realistic scenario in which retroreflection is predicted to occur in the Dirac semimetal Cd₃As₂, as a result of its tilted dispersion relation.

关键词： Angiopoietin-2 (ANGPT2)   Vascular remodeling   Extracellular matrix   Endothelial cell stability   Angiogenesis  

摘要： Pulmonary arterial hypertension (PAH) is a progressive disorder characterized by pulmonary vascular remodeling and right heart failure, in which endothelial dysfunction plays a central role. Angiopoietin-2 (ANGPT2) has been implicated in endothelial injury and vascular remodeling in multiple diseases; however, its role in hypoxic PAH remains incompletely understood. This study investigated the role and underlying mechanisms of ANGPT2 in PAH, with a particular focus on endothelial integrity, permeability, and vascular remodeling. Gene expression profiling was performed using lung tissues from patients with PAH, and ANGPT2 expression was further evaluated in plasma and lung tissues. Its functional role was examined in hypoxia-induced and Sugen/hypoxia (SuHx)-induced animal models of PAH. The effects of ANGPT2 inhibition by AAV-shANGPT2 delivery on hemodynamics, right ventricular function, and vascular remodeling were assessed. In vitro, pulmonary artery endothelial cells (PAECs) were used to evaluate the effects of ANGPT2 on proliferation, migration, and extracellular matrix remodeling. ANGPT2 expression was significantly increased in patients with PAH and in experimental models, and its levels correlated with indices of disease severity. Inhibition of ANGPT2 attenuated pulmonary hypertension, reduced right ventricular hypertrophy, and ameliorated pulmonary vascular remodeling, including collagen deposition and small-vessel muscularization. In PAECs, ANGPT2 inhibition restored impaired migration and tube formation and attenuated hypoxia-induced cell cycle progression. Mechanistically, ANGPT2 regulated integrin expression and activated focal adhesion kinase (FAK) signaling, thereby influencing endothelial adhesion, migration, and extracellular matrix remodeling. Collectively, these findings identify ANGPT2 as an important mediator of pulmonary vascular remodeling in experimental PAH and support ANGPT2 inhibition as a potential therapeutic approach warranting further pr

关键词： Anti-neuroinflammation activity   Clerodane diterpenoids and acetophenones   DP4+ statistical analysis   Electronic circular dichroism calculation   NLRP3 and IL-1β   Solidago canadensis  

摘要： Neuroinflammation is a key pathogenic factor in neurodegenerative diseases, while the anti-neuroinflammatory effects of Solidago canadensis L. have not been reported to date. This study aimed to identify the anti-neuroinflammatory active components of S. canadensis and elucidate their regulatory effects on neuroinflammation-related protein expression. A total of 20 compounds, including 17 clerodane diterpenoids (1–7 and 10–19) and 3 acetophenone derivatives (8, 9, and 20) were isolated from S. canadensis. Seven clerodane diterpenoids (1–7) and two acetophenone compounds (8 and 9) are previously unreported, and their structures were were elucidated via a comprehensive approach integrating spectroscopic data analysis, empirical stereochemical rules, DP4+ probability analysis using GFN2NMR, and ECD calculations. Compounds 1–5 are novel 1,2-seco-(3 → 1)-abeo-clerodane diterpenoids, which expand the chemical diversities of the genus Solidago. The anti-neuroinflammatory activity of all isolated compounds was evaluated in LPS-stimulated BV2 microglial cells. The results revealed that compounds 3, 10, 11, 12, 17, and 18 exhibited potent activity, yielding IC₅₀ values of 14.54, 12.35, 14.32, 16.42, 13.86, and 15.64 μM, respectively. Western Blot analysis demonstrated that these compounds decreased NLRP3 and IL-1β protein expressions to display anti-neuroprotective effects. These results support the potential of clerodane diterpenoids from S. canadensis as anti-neuroinflammatory agents for treating neurodegenerative diseases.

关键词： Crystal structure   Cu2+ion   Dye adsorption   Metal-organic framework  

摘要： A porous metal-organic framework (MOF), {[Cu₂(bpy)_1.5(MTPCA)₂]·4CH₃OH·H₂O}_n (Cu-MTPCA), was synthesized through a solvothermal reaction between Cu(NO₃)₂·6H₂O and 6-methyl-4-(1H-1,2,4-triazol-1-yl)pyridine carboxylic acid (MTPCA) in the presence of linear linker 4,4′-bipyridine. Cu-MTPCA exhibits as a (3, 3, 6-c net) skeleton with numerous Lewis basic sites present on the inner walls of the pores. UV–vis studies confirmed that Cu-MTPCA exhibited remarkable adsorption efficiency towards anionic dyes such as methyl orange (MO^–), congo red (CR^2–), and titan yellow (TY^2–), achieving removal rates of 91.51%, 97.85%, and 58.5%, respectively. In addition, Cu-MTPCA also demonstrated good adsorption performance for methyl orange in mixed anionic and cationic dyes of MB⁺/ MO^–. More importantly, Cu-MTPCA holds potential for recycling after adsorption.

关键词： ion channel   channelrhodopsin   gating mechanism   proton transfer   ion transport  

摘要： Light-gated anion channelrhodopsins are widely used as optogenetic silencers, yet the molecular events underlying gate opening and closing remain unclear. Here we show that gate closure in Guillardia theta anion channelrhodopsin 1 (GtACR1) is tightly coupled to coordinated proton-transfer reactions. Time-resolved spectroscopic and electrochemical analyses reveal that formation of the M-intermediate, which governs gate closure, involves not only deprotonation of the retinal Schiff base but also proton release from Asp234 to the extracellular side. We further demonstrate that residues Tyr207 and Cys237 participate in a hydrogen-bond network that modulates retinal Schiff base deprotonation, with Cys237 undergoing deprotonation during M-intermediate formation. In addition, analyses of the dark state provide new experimental evidence regarding the protonation states of functionally important residues in GtACR1, while characterization of the L-intermediate reveals hydrogen-bond rearrangements associated with channel activation. Together, these findings support a mechanistic model in which proton transfer reactions involving Asp234, Tyr207, and Cys237 coordinate retinal Schiff base deprotonation, thereby driving gate closure in GtACR1.

关键词： Pain   S1P   S1PR1   Ozanimod   Corticotropin releasing hormone   Central amygdala   Central lateral amygdala   slice electrophysiology  

摘要： A key brain structure in the processing of chronic pain is the central nucleus of the amygdala (CeA), which has justifiably been termed the “nociceptive amygdala.” Prior work shows that a major subclass of neurons in the lateral region of the CeA (CeL) expressing corticotropin-releasing hormone (CRH; CeL^CRH + neurons) is sensitized in the acute, but not chronic, stage of neuropathic pain. However, the signal transduction regulation of synaptic activity in CeL^CRH + neurons remains poorly understood. The goal of this work was to elucidate the modulation of CeL^CRH + neuron synaptic activity by sphingosine-1-phosphate receptor 1 (S1PR₁) signaling in neuropathic pain. Here we performed whole-cell patch-clamp electrophysiological recordings in acute brain slices from male mice subjected to the spared nerve injury (SNI) model of neuropathic pain to measure how pharmacological modulation of S1PR₁ alters synaptic properties of CeL^CRH + neurons. In sham, but not SNI mouse, we found S1PR₁ agonism reduced the frequency of excitatory input onto CeL^CRH + neurons, while S1PR₁ antagonism had no effect on either surgical group. We also show SNI increased the frequency of inhibitory input onto CeL^CRH + neurons which was normalized by both an S1PR₁ agonist and antagonist, as well as the clinically relevant S1PR_1,5 agonist, Ozanimod. Together, our data suggest SNI alters excitatory and inhibitory inputs onto CeL^CRH + neurons, and each type of input is differentially modulated by S1PR₁ signaling, highlighting CeL^CRH + neurons as key nodes in neuropathic pain circuitry and identifying S1PR₁s as a potential target for the development of new analgesic pharmacotherapies.

关键词： Doping   Electrode materials   Medium-entropy   NiCo2O4   Supercapacitors  

摘要： To enhance the high-temperature stability and electrochemical performance of spinel-type NC, medium-entropy spinel electrode materials, NCMC and NCMCE2, were synthesized using a coprecipitation method.¹ This synthesis involved the introduction of a Co-Mn-Cr ternary system at the B-site, along with a strategy of partially substituting Cr with Eu. For comparative purposes, NC was also prepared via the same method. FETEM and TEM analyses reveal that both NCMC and NCMCE2 synthesized at 500 °C exhibited particle agglomeration, with primary spherical grains measuring 6.72 and 8.42 nm in diameter, respectively. At this temperature, XRD analysis revealed that NC decomposed, while the synthesized medium-entropy NCMC and NCMCE2 maintained a single-phase spinel structure, demonstrating superior high-temperature structural stability compared to NC. Electrochemical tests indicated that the NCMCE2 electrode exhibited a specific capacitance of 350.91 F g⁻¹ at a current density of 1 A g⁻¹ in a 2 M KOH electrolyte, outperforming the NCMC electrode, which showed a specific capacitance of 318.18 F g⁻¹. After 3000 cycles at 10 A g⁻¹, the specific capacitance remains at 100%. Additionally, ASC was constructed using NCMCE2 as the positive electrode and activated carbon as the negative electrode. This device delivered an energy density of 32.82 Wh kg⁻¹ at a power density of 0.8 kW kg⁻¹ and retained 100% of the capacitance after 12,000 charge–discharge cycles.

关键词： 1,2,3-Triazoles   4,5-Dichloropyridazinone   Anticancer MDA-MB-231   CuAAC   Cytotoxicity   Molecular docking  

摘要： An environmentally sustainable “Click green atmosphere” of CuAAC protocol in water was solicitly executed for the green synthesis of 4,5-dichloropyridazin-3(2H)-one linked 1,2,3-triazole hybrids in high purity and yield with a prospective safer and selective anticancer potency. Fully characterized triazole hybrids upon anticancer potency screening against breast (MDA-MB-231), colorectal (HCT-116), prostate (PC-3) cancer cell lines, and normal kidney (HEK-293) cell lines exhibited strong anti-proliferative potency with minimal cytotoxicity against normal cells as inferred by 4′,6-Di-Amidino-2-PhenylIndole (DAPI), Mitochondrial Membrane Potential (MMP) and Sulfo- Rhodamine B (SRB) assay. Compound 4b with IC₅₀ value of 1.60, 4.01, 3.73, and 21.27 μM, found better and safer than respective precursor alkyne 2 with IC₅₀ value of 2.52, 7.58, 7.81, and 20.10 μM, respectively. The in vitro inhibitory effect of 4b on MDA-MB-231 showed cells adhesion, invasion, and migration, which was fairly supported by in silico molecular docking with Epidermal Growth Factor Receptor (EGFR) tyrosine kinase domain (PDB ID: 1m17) and ADMET predictions.