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The oxidation of benzylic alcohols is an important transformation in modern organic synthesis. A plethora of photoredox protocols have been developed to achieve the aerobic oxidation of alcohols into carbonyls. Recently, several groups described that ultraviolet (UV) or purple light can initiate the aerobic oxidation of benzylic alcohols in the absence of an external catalyst, and depicted different mechanisms involving the photoinduction of •O2− as a critical reactive oxygen species (ROS). However, based on comprehensive mechanistic investigations, including control experiments, radical quenching experiments, EPR studies, UV–vis spectroscopy, kinetics studies, and density functional theory calculations (DFT), we elucidate here that HOO•, which is released via the H2O2 elimination of α-hydroxyl peroxyl radicals [ArCR(OH)OO•], serves as the real chain carrier for the autocatalytic photooxidation of benzylic alcohols. The mechanistic ambiguities depicted in the precedent literature are clarified, in terms of the crucial ROS and its evolution, the rate-limiting step, and the primary radical cascade. This work highlights the necessity of stricter mechanistic analyses on UV-driven oxidative reactions that involve aldehydes’ (or ketones) generation.

As typical transition metal dichalcogenides (TMDC), tungsten selenide (WSe2) nanosheets (nano-WSe2) are widely used in various fields due to their layered structures and highly tunable electronic and magnetic properties, which results in the unwanted release of tungsten (W) and selenium (Se) into the environment. However, the environmental effects of nano-WSe2 in plants are still unclear. Herein, we evaluated the impacts and fate of nano-WSe2 and micro-WSe2 in rice plants (Oryza sativa L.). It was found that both nano-WSe2 and micro-WSe2 did not affect the germination of rice seeds up to 5000 mg/L but nano-WSe2 affected the growth of rice seedlings with shortened root lengths. The uptake and transportation of WSe2 was found to be size-dependent. Moreover, W in WSe2 was oxidized to tungstate while Se was transformed to selenocysteine, selenomethionine, SeIV and SeVI in the roots of rice when exposed to nano-WSe2, suggesting the transformation of nano-WSe2 in rice plants. The exposure to nano-WSe2 brought lipid peroxidative damage to rice seedlings. However, Se in nano-WSe2 did not contribute to the synthesis of glutathione peroxidase (GSH-Px) since the latter did not change when exposed to nano-WSe2. This is the first report on the impacts and fate of nano-WSe2 in rice plants, which has raised environmental safety concerns about the wide application of TMDCs, such as WSe2 nanosheets.

1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. UV-Vis spectra and fluorescence spectra were measured. Density functional theory calculations on the structure of the title compound were performed at the B3LYP/6-311G** level of theory. NPA atomic charge distributions indicate that, although the S atom in the thienyl ring loses coordination capacity, the title compound still may be used as a potential multi-dentate ligand to coordinate with metallic ions. The calculation of the second order optical nonlinearity was carried out. Natural bond orbital analyses indicate that the electronic absorption bands are mainly derived from the contribution of n → π* and π → π* transitions. Fluorescence spectra determination shows that the title compound is a potential orange-light emitting material.

Proteomic profiling of extracellular vesicles (EVs) represents a promising approach for early detection and therapeutic monitoring of diseases such as cancer. The focus of this study was to apply robust EV isolation and subsequent data-independent acquisition mass spectrometry (DIA-MS) for urinary EV proteomics of prostate cancer and prostate inflammation patients. Urinary EVs were isolated by functionalized magnetic beads through chemical affinity on an automatic station, and EV proteins were analyzed by integrating three library-base analyses (Direct-DIA, GPF-DIA, and Fractionated DDA-base DIA) to improve the coverage and quantitation. We assessed the levels of urinary EV-associated proteins based on 40 samples consisting of 20 cases and 20 controls, where 18 EV proteins were identified to be differentiated in prostate cancer outcome, of which three (i.e., SERPINA3, LRG1, and SCGB3A1) were shown to be consistently upregulated. We also observed 6 out of the 18 (33%) EV proteins that had been developed as drug targets, while some of them showed protein-protein interactions. Moreover, the potential mechanistic pathways of 18 significantly different EV proteins were enriched in metabolic, immune, and inflammatory activities. These results showed consistency in an independent cohort with 20 participants. Using a random forest algorithm for classification assessment, including the identified EV proteins, we found that SERPINA3, LRG1, or SCGB3A1 add predictable value in addition to age, prostate size, body mass index (BMI), and prostate-specific antigen (PSA). In summary, the current study demonstrates a translational workflow to identify EV proteins as molecular markers to improve the clinical diagnosis of prostate cancer.

A novel sensing system has been designed for the detection of cupric ions. It is based on the quenched fluorescence signal of carbon dots (CDs), which were carbonized from poly(vinylpyrrolidone) (PVP) and L-Cysteine (CYS). Cupric ions interact with the nitrogen and sulfur atoms on surface of the CDs to form an absorbed complex; this results in strong quenching of the fluorescence of the CDs via a fast metal-to-ligand binding affinity. The synthesized water-soluble CDs also exhibited a quantum yield of 7.6%, with favorable photoluminescent properties and good photostability. The fluorescence intensity of the CDs was very stable in high ionic strength (up to 1.0 M NaCl) and over a wide range of pH levels (2.0−12.0). This facile method can therefore develop a sensor that offers reliable, fast, and selective detection of cupric ions with a detection limit down to 0.15 μM and a linear range from 0.5 to 7.0 μM (R2 = 0.980). The CDs were used for cell imaging, observed that they were low toxicity to Tramp C1 cells and exhibited blue and green and red fluorescence under a fluorescence microscope. In summary, the CDs exhibited excellent fluorescence properties, and could be applied to the selective and sensitive detection of cupric ion and multicolor cell imaging.