In-vitro Approaches to Investigate the Detrimental Effect of Light on Dopaminergic Neurons.

Our recent study revealed that fluorescent lamp light can penetrate deep into the brain of mice and rats leading to the development of typical histological characteristics associated with Parkinson's disease such as the loss of dopamine neurons in the substantia nigra. Monochromatic LED lights were thus used in this work to deepen our knowledge on the effects of the major wavelength peaks of fluorescent light on mouse and human dopaminergic cells. In particular, we exposed immortalized dopaminergic MN9D neuronal cells, primary cultures of mouse mesencephalic dopaminergic cells and human dopaminergic neurons differentiated from induced pluripotent stem cells (hiPSC) to different LED light wavelengths.

Bidimensional Engineered Amorphous -SnO Interfaces: Synthesis and Gas Sensing Response to HS and Humidity.

Two-dimensional (2D) transition metal dichalcogenides (TMDs) and metal chalcogenides (MCs), despite their excellent gas sensing properties, are subjected to spontaneous oxidation in ambient air, negatively affecting the sensor's signal reproducibility in the long run. Taking advantage of spontaneous oxidation, we synthesized fully amorphous -SnO 2D flakes (≈30 nm thick) by annealing in air 2D SnSe for two weeks at temperatures below the crystallization temperature of SnO ( < 280 °C). These engineered -SnO interfaces, preserving all the precursor's 2D surface-to-volume features, are stable in dry/wet air up to 250 °C, with excellent baseline and sensor's signal reproducibility to HS (400 ppb to 1.

Formation of a two-dimensional oxide oxidation of a layered material.

We investigate the oxidation mechanism of the layered model system GeAs. X-ray photoelectron spectroscopy experiments performed by irradiating an individual flake with synchrotron radiation in the presence of oxygen show that while As leaves the GeAs surface upon oxidation, a Ge-rich ultrathin oxide film is being formed in the topmost layer of the flake. We develop a theoretical model that supports the layer-by-layer oxidation of GeAs, with a logarithmic kinetics.

Emerging oxidized and defective phases in low-dimensional CrCl.

Two-dimensional (2D) magnets such as chromium trihalides CrX (X = I, Br, Cl) represent a frontier for spintronics applications and, in particular, CrCl has attracted research interest due its relative stability under ambient conditions without rapid degradation, as opposed to CrI. Herein, mechanically exfoliated CrCl flakes are characterized at the atomic scale and the electronic structures of pristine, oxidized, and defective monolayer CrCl phases are investigated employing density functional theory (DFT) calculations, scanning tunneling spectroscopy (STS), core level X-ray photoemission spectroscopy (XPS), and valence band XPS and ultraviolet photoemission spectroscopy (UPS). As revealed by atomically resolved transmission electron microscopy (TEM) and energy dispersive X-ray (EDX) analysis, the CrCl flakes show spontaneous surface oxidation upon air exposure with an extrinsic long-range ordered oxidized O-CrCl structure and amorphous chromium oxide formation on the edges of the flakes.