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Widely acknowledged that the capacity of Li‐O2 batteries (LOBs) should be strongly determined by growth behaviors of the discharge product of lithium peroxide (Li2O2) that follows both coexisting surface and solution pathways. However until now, it remains still challenging to achieve dynamic modulation on Li2O2 morphologies. Herein, the photo‐responsive Au nanoparticles (NPs) supported on reduced oxide graphene (Au/rGO) have been utilized as cathode to manipulate oxygen reduction reaction (ORR) kinetics by aid of surface plasmon resonance (SPR) effects. Thus, we can experimentally reveal the importance of matching ORR kinetics with Li+ migration towards battery performance. Moreover, it is found that Li+ concentration polarization caused "sudden death" of LOBs is supposed to be just a form of suspended animation that could timely recover under irradiation. This work provides us an in‐depth explanation on the working mechanism of LOBs from a kinetic perspective, offering valuable insights for the future battery design. [ABSTRACT FROM AUTHOR]

To assess the water resource carrying capacity of Guyuan City, an analysis was conducted using the load index method, principal component analysis, and ecological water footprint method. A comprehensive analysis was carried out using these three methods to evaluate the current state of water resource carrying capacity in Guyuan City. The results indicate that the water resource carrying capacity in Guyuan City is mainly influenced by economic development factors, water supply–demand balance factors, and natural factors. During the period from 2002 to 2016, the water resource carrying capacity fluctuated in response to changes in the total water resources. However, from 2016 to 2021, it exhibited an increasing trend due to improvements in water resource utilization efficiency and effective water conservation measures. However, the water resource carrying capacity remains at a relatively low level, and it has consistently been in an overloaded state, with the development and utilization of water resources approaching their limits. Water scarcity in Guyuan City is a pressing concern, characterized by severe limitations on its potential for development and utilization. The persistent supply–demand imbalance is anticipated to impede the region's pursuit of high-quality economic development in the foreseeable future. [ABSTRACT FROM AUTHOR]

The theoretically high‐energy‐density lithium–sulfur batteries (LSBs) are seriously limited by the disadvantages including the shuttle effect of soluble lithium polysulfides (LiPSs) and the sluggish sulfur redox kinetics, especially for the most difficult solid–solid conversion of Li2S2 to Li2S. Herein, a multifunctional catalytic interlayer to improve the performance of LSBs is tried to introduce, in which Fe1–xS/Fe3C nanoparticles are embedded in the N/S dual‐doped carbon network (NSC) composed by nanosheets and nanotubes (the final product is named as FeSC@NSC). The well‐designed 3D NSC network endows the interlayer with a satisfactory LiPSs capture‐catalytic ability, thus ensuring fast redox reaction kinetics and suppressing LiPSs shuttling. The density functional theory calculations disclose the catalytic mechanisms that FeSC@NSC greatly improves the liquid–solid (LiPSs to Li2S2) conversion and unexpectedly the solid–solid (Li2S2 to Li2S) one. As a result, the LSBs based on the FeSC@NSC interlayer can achieve a high specific capacity of 1118 mAh g−1 at a current density of 0.2 C, and a relatively stable capacity of 415 mAh g−1 at a large current density of 2.0 C after 700 cycles as well as superior rate performance. [ABSTRACT FROM AUTHOR]

In this work, we have successfully triggered the aqueous auto‐redox reactions between reductive Ce(OH)3 and oxidative MnO4−/Pd2+ ions to form PdO/Mn3O4/CeO2 (PMC) nanocomposites. PMC could spontaneously self‐assemble into compact encapsulation on the surface of halloysite nanotubes (HNTs) to form the final one dimensional HNTs supported PMCs (HPMC). It is identified that there exists strong synergistic effects among the components of PdO, Mn3O4, and CeO2, and hence HPMC could show excellent performance on photoassisted thermal catalytic CH4 combustion that its light‐off temperature was sharply reduced to be 180 °C under visible light irradiation. Based on detailed studies, it is found that the catalytic reaction process well follows the classic MVK mechanism, and adsorption/activation of O2 into active oxygen species (O*) should be the rate‐determining step for CH4 conversion. [ABSTRACT FROM AUTHOR]

Resin-based pit-and-fissure sealants are often used to form a barrier on the occlusal surface of molars to treat caries lesions; however, bacteria can remain in the pit and fissures without detection, increasing the risk of secondary caries. Sealants with antimicrobial properties or microbial repellent actions might be advantageous. The aim of this study was to assess the inhibitory effect of a 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB)-incorporated sealant against Streptococcus mutans. MAE-DB (4% wt) was incorporated into a commercially available sealant, Eco-S resin-based pit-and-fissure sealant (Vericom Co., Ltd., Korea); a sealant without MAE-DB served as a negative control, and Clinpro™ Sealant (3M™ ESPE™), a fluoride-releasing resin, was used as a commercial control. The effects of the cured sealants and their eluents on the growth of S. mutans were determined according to colony-forming unit counts and metabolic tests. The effects of the cured sealants on the adherence and membrane integrity of S. mutans were investigated using confocal laser-scanning microscopy (CLSM) in conjunction with fluorescent indicators. Compared with the negative control and commercial control, the cured MAE-DB-incorporated pit-and-fissure sealant exhibited a significant inhibitory effect on the growth of S. mutans (P < 0.05), whereas the eluents did not show any detectable antibacterial activity. The commercial control also showed no detectable bactericidal activity. Moreover, the aged experimental material retained its property of contact inhibition of biofilm formation. The fluorescence analysis of CLSM images demonstrated that the cured MAE-DB-incorporated sealant could hamper the adherence of S. mutans and exert a detrimental effect on bacterial membrane integrity. The incorporation of MAE-DB can render a pit-and-fissure sealant with contact antibacterial activity after polymerization via influencing the growth, adherence, and membrane integrity of S. mutans. Therefore, MAE-DB-containing pit-and-fissure sealant shows promise for preventing or controlling dental caries on occlusal pit and fissures of molars. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the involvement of intrinsic mitochondrial apoptosis in dental monomer-induced cytotoxicity and the influences of N-acetyl cysteine (NAC) on this process. Methods: Human dental pulp cells (hDPCs) were exposed to several dental monomers in the absence or presence of NAC, and cell viability, intracellular redox balance, morphology and function of mitochondria and key indicators of intrinsic mitochondrial apoptosis were evaluated using various commercial kits. Results: Dental monomers exerted dose-dependent cytotoxic effects on hDPCs. Concomitant to the over-production of reactive oxygen species (ROS) and depletion of glutathione (GSH), differential changes in activities of superoxide dismutase, glutathione peroxidase, and catalase were detected. Apoptosis, as indicated by positive Annexin V/propidium iodide (PI) staining and activation of caspase-3, was observed after dental monomer treatment. Dental monomers impaired the morphology and function of mitochondria, and induced intrinsic mitochondrial apoptosis in hDPCs via up-regulation of p53, Bax and cleaved caspase-3, and down-regulation of Bcl-2. NAC restored cell viability, relieved oxidative stress and blocked the apoptotic effects of dental monomers. Conclusions: Dental monomers induced oxidative stress and mitochondrial intrinsic apoptosis in hDPCs. NAC could reduce the oxidative stress and thus protect hDPCs against dental monomer-induced apoptosis. [ABSTRACT FROM AUTHOR]

Objectives This study was aimed to evaluate the anti-matrix metalloproteinases (MMPs) ability of active components from citrus fruits (hesperetin: Hst, hesperidin: Hsd and naringenin: Nge). Methods Inactivation effects of citrus flavonoids (Hst, Hsd, Nge) at different concentrations on soluble collagenase were measured using a fluorometric assay. Matrix-bound endogenous MMPs activity was evaluated via dry mass loss and hydroxyproline (HYP) release of demineralized human dentin. Demineralized dentin beams were pretreated with 500 μg/mL citrus flavonoids for 10 min. Chlorhexidine (CHX) was used as inhibitor control. Beams pretreated with distilled water served as blank control. Dentin slabs were used for in situ zymography and evaluated under confocal microscopy. Ultrastructure of demineralized collagen fibers was exhibited by Transmission Electron Microscopy (TEM). Results Citrus flavonoids exhibited inactivation function on soluble MMPs and the extent of inactivation increased in a dose-dependent manner. The inactivation percent of citrus flavonoids reached above 90% at the concentration of 500 μg/mL. Compared with control group, citrus flavonoids pretreated demineralized dentin beams exhibited less dry mass loss, lower hydroxyproline release and more intact collagen architecture after 15 days storage. Dentin samples pretreated with citrus flavonoids showed lower enzymes activities in in situ zymography. Conclusions Hst, Hsd or Nge have anti-MMPs ability and can preserve dentin collagen from degradation. Clinical Significance: Hst, Hsd and Nge may have the potential to be used in dentin bonding systems and improve the resin-dentin bonding durability. [ABSTRACT FROM AUTHOR]