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The increasing desire for aesthetically pleasing teeth has resulted in the widespread use of tooth whitening treatments. Clinical tooth whitening products currently rely on hydrogen peroxide formulations to degrade dental pigments through oxidative processes. However, they usually cause side effects such as tooth sensitivity and gingival irritation due to the use of high concentrations of hydrogen peroxide or long-time contact. In recent years, various novel materials and reaction patterns have been developed to tackle the issues related to H2O2-based tooth whitening. These can be broadly classified as advanced oxidation processes (AOPs). AOPs generate free radicals that have potent oxidizing properties, which can thereby increase the oxidation power and/or reduce the exposure time and can probably minimize the side effects of tooth bleaching. While there have been several reviews on clinical tooth whitening and the application of novel nanomaterials, a review based on the concept of AOPs in tooth bleaching application has not yet been conducted. This review describes the common types and mechanisms of AOPs, summarizes the latest research progress of new tooth bleaching materials based on AOPs, and proposes a model for tooth bleaching and a rate control step at the molecular level. The paper also reviews the shortcomings and suggests future development directions. [ABSTRACT FROM AUTHOR]

Renewable energy is an important means of addressing climate change and achieving carbon peaking and carbon neutrality goals. However, the uncertainty and randomness of renewable energy also have a certain impact on the flexibility, reliability, and transient voltage stability of the power system. These effects also pose great challenges to power system planning. In order to address the impact of renewable energy on power system planning, this paper proposes a two-layer optimization model for power sources and network planning which takes into account both reliability and transient voltage stability requirements. The upper-layer grid planning problem is formulated with consideration of the system reliability index, and the transient stability requirements and construction and operation costs are included in the lower-layer problem to determine a construction scheme for power generation and energy storage units. To solve the complex nonlinear problem efficiently, a two-layer iterative algorithm utilizing the adaptive particle swarm optimization (PSO) technique is proposed. The effectiveness of the proposed method is demonstrated via its application to the IEEE 33 test system. The results show that the proposed optimization approach effectively addresses the power system transmission and generation planning problem while improving the efficiency and reliability of the system's operation. The findings can guide the design and implementation of future power system planning and operation strategies. [ABSTRACT FROM AUTHOR]

Human leukocyte antigen (HLA) can encode the human major histocompatibility complex (MHC) proteins and play a key role in adaptive and innate immunity. Emerging clinical evidences suggest that the presentation of tumor neoantigens and neoantigen-specific T cell response associated with MHC class I molecules are of key importance to activate the adaptive immune systemin cancer immunotherapy. Therefore, accurate HLA typing is very essential for the clinical application of immunotherapy. In this study, we conducted performance evaluations of 4 widely used HLA typing tools (OptiType, Phlat, Polysolver and seq2hla) for predicting HLA class Ia genes from WES and RNA-seq data of 28 cancer patients. HLA genotyping data using PCR-SBT method was firstly obtained as the golden standard and was subsequently compared with HLA typing data by using NGS techniques. For both WES data and RNA-seq data, OptiType showed the highest accuracy for HLA-Ia typing than the other 3 programs at 2-digit and 4-digit resolution. Additionally, HLA typing accuracy from WES data was higher than from RNA-seq data (99.11% for WES data versus 96.42% for RNA-seq data). The accuracy of HLA-Ia typing by OptiType can reach 100% with the average depth of HLA gene regions >20x. Besides, the accuracy of 2-digit and 4-digit HLA-Ia typing based on control samples was higher than tumor tissues. In conclusion, OptiType by using WES data from control samples with the high average depth (>20x) of HLA gene regions can present a probably superior performance for HLA-Ia typing, enabling its application in cancer immunotherapy. [ABSTRACT FROM AUTHOR]

The aims of the current study were to examine the signaling mechanisms for transforming growth factor‐β1 (TGF‐β1)‐induced rat airway smooth muscle cell (ASMC) proliferation and to determine the effect of activation of peroxisome proliferation–activated receptor‐γ (PPAR‐γ) on TGF‐β1‐induced rat ASMC proliferation and its underlying mechanisms. TGF‐β1 upregulated microRNA 21 (miR‐21) expression by activating Smad2/3, and this in turn downregulated forkhead box O1 (FOXO1) mRNA expression. In addition, TGF‐β1–Smad–miR‐21 signaling also downregulated phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression and thus de‐repressed the PI3K–Akt pathway. Depletion of PTEN reduced the nuclear FOXO1 protein level without affecting its mRNA level. Inhibition of the PI3K–Akt pathway or proteasome function reversed PTEN knockdown‐induced nuclear FOXO1 protein reduction. Our study further showed that loss of FOXO1 increased cyclin D1 expression, leading to rat ASMC proliferation. Preincubation of rat ASMCs with pioglitazone, a PPAR‐γ activator, blocked TGF‐β1‐induced activation of Smad2/3 and its downstream targets changes of miR‐21, PTEN, Akt, FOXO1, and cyclin D1, resulting in the inhibition of rat ASMC proliferation. Our study suggests that the activation of PPAR‐γ inhibits rat ASMC proliferation by suppressing Smad–miR‐21 signaling and therefore has a potential value in the prevention and treatment of asthma by negatively modulating airway remodeling. TGF‐β1 stimulates rat ASMC proliferation by the Smad2/3‐mediated induction of miR‐21, which consequently reduces PTEN, de‐represses Akt activity, downregulates FOXO1 expression, and upregulates cyclin D1. [ABSTRACT FROM AUTHOR]

As a new smart material,dielectric electroactive polymer can be used to transforming mechanical energy such as wind power and water power into electrical energy. The energy harvesting mechanisms and working cycles of DEAP transducer were investigated. Three different cycles including constant charges,constant electrical voltage and constant electrical field were compared. Based on the working cycles,the energy conversion between mechanical energy inputted and electrical energy generated have been studied. With the proposed model of DEAP transducer,the force-stroke of generator in the stretching process with voltage on and the retracting process with voltage off were determined. With the force-stroke of generator,the energy generated and energy conversion efficiency were calculated. It is demonstrated that the stretch displacement and bias voltage are the main factors influencing the amount of electrical energy generated and the efficiency of energy conversion. In addition,the theoretical analysis results were validated by the experiments.

A novel sustained chlorine-releasing polydimethylsiloxane/Ca(ClO) 2 (PDMS/Ca(ClO) 2 ) material was fabricated by encapsulating Ca(ClO) 2 in a PDMS matrix due to its high hydrophobicity and high chemical stability, which showed immediate-responsive and long-lasting antibacterial capabilities in aqueous conditions. Free chlorine could be released from the PDMS/Ca(ClO) 2 after immersion in water for 2 min and could also be sustainedly released for 2 weeks, while the released concentration is negatively related to the duration time and positively with the initial Ca(ClO) 2 contents. Additionally, Ca(ClO) 2 powder as a filler significantly affects the crosslinking and pore size of PDMS. The PDMS/Ca(ClO) 2 materials exhibited enduring antibacterial performance against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) in both planktonic and multispecies-biofilm status. It is expected that this PDMS/Ca(ClO) 2 material and its similar composite would be promising candidates for wide sustainable disinfection applications in biomedical and industrial fields., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Purpose: A synergistic antibacterial system employing photocatalytic performance and low-temperature photothermal effect (LT-PTT) with the potential for infectious skin wound healing promotion was developed., Methods: Ag/Ag 2 O was synthesized with a two-step method, and its physicochemical properties were characterized. After its photocatalytic performance and photothermal effect were evaluated under 0.5 W/cm 2 808 nm NIR laser irradiation, its antibacterial activities in both planktonic and biofilm forms were then studied in vitro targeting Staphylococcus Aureus (S. aureus) , and the biocompatibility was tested with L-929 cell lines afterward. Finally, the animal model of dorsal skin wound infection was established on Sprague-Dawley rats and was used to assess infectious wound healing promotion of Ag/Ag 2 O in vivo., Results: Ag/Ag 2 O showed boosted photocatalytic performance and local temperature accumulation compared with Ag 2 O when exposed to 0.5 W/cm 2 808 nm NIR irradiation, which therefore endowed Ag/Ag 2 O with the ability to kill pathogens rapidly and cleavage bacterial biofilm in vitro. Furthermore, after treatment with Ag/Ag 2 O and 0.5 W/cm 2 808 nm NIR irradiation, infectious wounds of rats realized skin tissue regeneration from a histochemical level., Conclusion: By exhibiting excellent NIR-triggered photocatalytic sterilization ability enhanced by low-temperature photothermal effect, Ag/Ag 2 O was promising to be a novel, photo-responsive antibacterial agent., Competing Interests: The authors report no conflicts of interest in this work., (© 2023 Qian et al.)