Publications by authors named "H Ramsden"

Article Synopsis
  • Atomic defects, particularly chalcogen vacancies, in monolayer transition metal dichalcogenides (TMDs) like MoS have significant effects on their properties.
  • A reproducible method involving annealing MoS at 600 °C in an argon/hydrogen atmosphere successfully induces these vacancies, leading to observable changes in photoluminescence and other spectra.
  • The study demonstrates that the defect peak seen at room temperature is due to excitons trapped in defect-induced states, revealing insights into how sulfur vacancies impact excitonic behavior in MoS at different temperatures.
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van der Waals heterostructures (vdW-HSs) integrate dissimilar materials to form complex devices. These rely on the manipulation of charges at multiple interfaces. However, at present, submicrometer variations in strain, doping, or electrical breakages may exist undetected within a device, adversely affecting macroscale performance.

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Neural circuits in the medial entorhinal cortex (MEC) encode an animal's position and orientation in space. Within the MEC spatial representations, including grid and directional firing fields, have a laminar and dorsoventral organization that corresponds to a similar topography of neuronal connectivity and cellular properties. Yet, in part due to the challenges of integrating anatomical data at the resolution of cortical layers and borders, we know little about the molecular components underlying this organization.

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The medial entorhinal cortex (MEC) is an increasingly important focus for investigation of mechanisms for spatial representation. Grid cells found in layer II of the MEC are likely to be stellate cells, which form a major projection to the dentate gyrus. Entorhinal stellate cells are distinguished by distinct intrinsic electrophysiological properties, but how these properties contribute to representation of space is not yet clear.

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The chromatographic separation of four proteins, cytochrome c, alpha 1-acid glycoprotein, ovalbumin, and beta-lactoglobulin, was achieved on a 4.6 X 250-mm wide-pore polyethyleneimine (PEI)-silica gel column (5-micron particles, 330-A pore size) with essentially baseline resolution using a 20-min linear gradient from 0.025 M potassium phosphate, pH 6.

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