Efficacy and influential factors of hematoporphyrin monomethyl ether mediated photodynamic therapy in the treatment for port-wine stains.

BACKGROUNDS: Hematoporphyrin monomethyl ether mediated photodynamic therapy (HMME-PDT) has emerged as an alternative approach for port-wine stain (PWS), which was primarily treated with pulsed dye laser (PDL). This study was aimed to evaluate the efficacy and safety of HMME-PDT for PWS and to explore influential factors on the efficacy. METHODS: A total of 254 patients were enrolled. Patients received an intravenous injection of HMME at 5 mg/kg. Lesion areas were irradiated with 532-nm light for 20-25 min. Efficacy was assessed according to fading of lesions and graded as excellent (≥90 %), good (60 %-89 %), fair (20 %-59 %), or poor (<20 %). Adverse events were recorded. Clinical data were analyzed including gender, age, lesion sub-type, lesion location and number of treatments. RESULTS: Overall, 72.4 % of patients achieved an effective response, with 27.6% showing excellent efficacy, 24.8 % showing good efficacy and 20.1 % showing fair efficacy. Only 27.6 % showed poor efficacy. Patients under the age of 18 obtained a better efficacy than adults. Lesions in face showed a better therapeutic outcome than those in neck or trunk and extremities. A more effective response was seen in pink type compared with nodular thickening type. Multiple HMME-PDT treatments could improve the clinical response. Lesion location, lesion sub-type, number of treatments were independent influential factors on efficacy. Adverse events included edema, blister, crust, hypopigmentation, hyperpigmentation, pain, itch and burning sensation. No severe systemic side events were observed. CONCLUSIONS: HMME-PDT was effective for treating PWS and was safe and well-tolerated by patients. It is worth further investigation in efficacy and safety involving more patients from medical institutions in different regions in China. The optimal treatment parameters and treatment protocols are still being explored in the clinical treatment for PWS.

Enhanced Catalytic Mechanism of Twin-Structured BiVO4.

Twin engineering is an efficient strategy to improve the photocatalytic activity of semiconductors (e.g., BiVO4). A systematic study that combines theory and experiments is conducted to reveal the underlying enhanced catalytic mechanism of twin-structured BiVO4. The key characteristic of twinned structures is the partial strain introduced by twin boundaries. Lattice distortion introduced by the twin boundaries leads to charge redistribution and built-in electronic fields between the twin boundaries and the bulk. The generated homojunctions possess a staggered band alignment structure, and their band offsets are increased by the Fermi-level pinning effect. The series of homojunctions in twinned structures is beneficial for facilitating charge separation. Additionally, lattice distortion around twin boundaries leads to the broken geometric symmetry of metal-oxygen polyhedrons in twinned crystals. The adsorption energies of adsorbates decrease significantly, resulting in reduction of the overpotential. The reduced overpotential favors acceleration of the oxygen evolution reaction on twinned structures.

Electronic excitation in graphene under single-particle irradiation.

Single-particle irradiation is a typical condition in space applications, which could be detrimental for electronic devices through processes such as single-event upset or latch-up. For functional devices made of few-atom-thick monolayers that are entirely exposed to the environment, the irradiation effects could be manifested through localized or delocalized electronic excitation, in addition to lattice defect creation. In this work, we explore the single-H irradiation effects on bare or coated graphene monolayers. Real-time time-dependent density functional theory-based first-principles calculation results elucidate the evolution of charge densities in the composite system, showing notable charge excitation but negligible charge deposition. A hexagonal boron nitride coating layer does not protect graphene from these processes. Principal component analysis demonstrates the dominance of localized excitation accompanied by nuclear motion, bond distortion and vibration, as well as a minor contribution from delocalized plasmonic excitation. The significance of coupled electron-ion dynamics in modulating the irradiation processes is identified from comparative studies on the spatial and temporal patterns of excitation for unconstrained and constrained lattices. The stopping power or energy deposition is also calculated, quantifying the dissipative nature of charge density excitation. This study offers fundamental understandings of the single-particle irradiation effects on optoelectronic devices constructed from low-dimensional materials, and inspires unconventional techniques to excite the electrons and ions in a controllable way.

In situ growth of large-area and self-aligned graphene nanoribbon arrays on liquid metal.

Intrinsic graphene features semi-metallic characteristics that limit its applications in electronic devices, whereas graphene nanoribbons (GNRs) are promising semiconductors because of their bandgap-opening feature. However, the controllable mass-fabrication of high-quality GNR arrays remains a major challenge. In particular, the in situ growth of GNR arrays through template-free chemical vapor deposition (CVD) has not been realized. Herein, we report a template-free CVD strategy to grow large-area, high-quality and self-aligned GNR arrays on liquid copper surface. The width of as-grown GNR could be optimized to sub-10 nm with aspect ratio up to 387, which is higher than those of reported CVD-GNRs. The study of the growth mechanism indicates that a unique comb-like etching-regulated growth process caused by a trace hydrogen flow guides the formation of the mass-produced self-aligned GNR arrays. Our approach is operationally simple and efficient, offering an assurance for the use of GNR arrays in integrated circuits.