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Monolayer MoS2 is an emerging two-dimensional semiconductor that has seen wide applications in optoelectronic and light-emitting devices. Here we report on the antenna-enhanced spontaneous emission of monolayer MoS2, which has weak absorbance and low intrinsic quantum yield. The ultrathin silver platelet antennas we use can both increase the absorption cross-section and improve the transmission efficiency via controlling the optical field at nanometer scale. Experimental results indicate the photoluminescence enhancement can reach 4 times, which is also supported by numerical analysis of both excitation and emission processes with respect to the thickness of spacer layer. This ultrathin structure can facilitate the development of on-chip emitters and valley-based devices, especially in cases of large area sample or flexible substrate.
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We demonstrate an unexpectedly strong surface-plasmonic absorption at the interface of silver and high-index dielectrics based on electron and photon spectroscopy. The measured bandwidth and intensity of absorption deviate significantly from the classical theory. Our density-functional calculation well predicts the occurrence of this phenomenon. It reveals that due to the low metal-to-dielectric work function at such interfaces, conduction electrons can display a drastic quantum spillover, causing the interfacial electron-hole pair production to dominate the decay of surface plasmons. This finding can be of fundamental importance in understanding and designing quantum nanoplasmonic devices that utilize noble metals and high-index dielectrics.
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INTRODUCTION: Chronic diabetic wounds pose a significant threat to the health of diabetic patients, representing severe and enduring complications. Globally, an estimated 2.5% to 15% of the annual health budget is associated with diabetes, with diabetic wounds accounting for a substantial share. Exploring new therapeutic agents and approaches to address delayed and impaired wound healing in diabetes becomes imperative. Traditional Chinese medicine (TCM) has a long history and remarkable efficacy in treating chronic wound healing. In this study, all topically applied proprietary Chinese medicines (pCMs) for wound healing officially approved by the National Medical Products Administration (NMPA) were collected from the NMPA TCM database. Data mining was employed to obtain a high-frequency TCM ingredients pair, Pearl-Borneol (1:1). METHOD: This study investigated the effect and molecular mechanism of the Pearl-Borneol pair on the healing of diabetic wounds by animal experiments and metabolomics. The results from animal experiments showed that the Pearl-Borneol pair significantly accelerated diabetic wound healing, exhibiting a more potent effect than the Pearl or Borneol treatment alone. Meanwhile, the metabolomics analysis identified significant differences in metabolic profiles in wounds between the model and normal groups, indicating that diabetic wounds had distinct metabolic characteristics from normal wounds. Moreover, Vaseline-treated wounds exhibited similar metabolic profiles to the wounds from the model group, suggesting that Vaseline might have a negligible impact on diabetic wound metabolism. In addition, wounds treated with Pearl, Borneol, and Pearl-Borneol pair displayed significantly different metabolic profiles from Vaseline-treated wounds, signifying the influence of these treatments on wound metabolism. Subsequent enrichment analysis of the metabolic pathway highlighted the involvement of the arginine metabolic pathway, closely associated with diabetic wounds, in the healing process under Pearl- Borneol pair treatment. Further analysis revealed elevated levels of arginine and citrulline, coupled with reduced nitric oxide (NO) in both the model and Vaseline-treated wounds compared to normal wounds, pointing to impaired arginine utilization in diabetic wounds. Interestingly, treatment with Pearl and Pearl-Borneol pair lowered arginine and citrulline levels while increasing NO content, suggesting that these treatments may promote the catabolism of arginine to generate NO, thereby facilitating faster wound closure. Additionally, borneol alone significantly elevated NO content in wounds, potentially due to its ability to directly reduce nitrates/nitrites to NO. Oxidative stress is a defining characteristic of impaired metabolism in diabetic wounds. RESULTS: The result showed that both Pearl and Pearl-Borneol pair decreased the oxidative stress biomarker methionine sulfoxide level in diabetic wounds compared to those treated with Vaseline, indicating that Pearl alone or combined with Borneol may enhance the oxidative stress microenvironment in diabetic wounds. CONCLUSION: In summary, the findings validate the effectiveness of the Pearl-Borneol pair in accelerating the healing of diabetic wounds, with effects on reducing oxidative stress, enhancing arginine metabolism, and increasing NO generation, providing a mechanistic basis for this therapeutic approach.
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In the title compound, [Cu(3)(CN)(3)(C(12)H(12)N(2))(2)], two 2,2'-bipyridine N,N'-chelated Cu(I) atoms are linked by a cyanide bridge that lies about a center of inversion; the Cu(I) atom exists in a tetra-hedral coordination geometry. This dinuclear entity is linked to another Cu(I) atom that lies on a twofold rotation axis by another cyanide bridge, these bridges giving rise to the formation of a linear chain motif.
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A new method has been developed for the determination of DNA by resonance light scattering with dodecyl dimethyl betaine (BS-12) in aqueous solution as a new probe. At pH 9.3, the interactions of BS-12 and DNA gave strong RLS signals at 388.0 nm. Linear relationships were found between the enhanced intensity of RLS and the concentration of DNAs in the range 0.25-12.0 microg x mL(-1) for fsDNA and 0.25-11.0 microg x mL(-1) for ctDNA. The limits of detection were 0.15 ng x mL(-1) and 0.16 ng x mL(-1) for fsDNA and ctDNA, respectively. The method was applied to the determination of synthetic samples with satisfactory results.