This work investigates the use of oxygen plasma (O 2 ) treatment, applied as an inductively coupled plasma, to control the thickness and work function of a MoS 2 layer. Plasma-etched MoS 2 exhibited a surface roughness similar to that of the pristine MoS 2 . The MoS 2 field effect transistors fabricated using the plasma-etched MoS 2 displayed a higher n-type doping concentration than that of pristine MoS 2 . The x-ray photoelectron spectroscopy was performed to analyze chemical composition to demonstrate the minimum level of chemical reactions occurred upon plasma treatment. Moreover, Kelvin probe force microscopy measurements were conducted to probe the changes in the work function that could be attributed to the changes in the surface potential. The measured work functions suggest the modification of a band structure and n-doping effect after plasma treatments that depended on the number of MoS 2 layers. This study suggests that the O 2 plasma can control the layer number of the MoS 2 as well as the electronic properties of a MoS 2 film.

Paranasal sinus drainage is mediated by mucociliary transport and gravity.However, human orthograde posture, along with the superior positioning of the maxillary sinus (MS) ostium, increases reliance on the mucociliary system.Previous research has thus suggested that differences in MS size and shape may impede mucociliary clearance, potentially contributing to disparities in sinusitis susceptibility. To further investigate this hypothesis, this study collected 29 three-dimensional (3D) coordinate landmarks and seven linear measurements of MS morphology from 167 computed tomography (CT) scans of crania of European, East Asian, or Equatorial African ancestry. MANOVA results reveal the Asian-derived individuals are characterized by both a significantly taller MS (F = 14.15, p < 0.0001) and a significantly greater distance from the MS floor to the ostium (F = 17.22, p < 0.0001) compared to those of European and African ancestry. A canonical variate (CV) analysis conducted on 3D landmark data provides corroborative results, distinguishing Asianderived individuals predominantly on the basis of a relatively lower MS floor.As a greater distance between the MS floor and ostium may impede mucociliary clearance, our results suggest MS anatomy may be a more prominent factor in chronic sinusitis among individuals of Asian ancestry compared to those of European and African ancestries. This provides tentative evidence of an anatomical etiology for chronic sinusitis even in the absence of anatomical variants/abnormalities (e.g., nasal polyps, concha bullosa, Haller's cells, and Agger nasi cells). Further research into the relationship between MS anatomy and sinusitis, in addition to socioeconomic inequalities of healthcare, is warranted to continue evaluating possible contributions to health disparities.

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Objectives: Although research into human maxillary sinus (MS) morphology has overwhelmingly focused on sinus volume, other aspects of morphology (e.g., overall shape, mucosal surface area) factor prominently in hypotheses regarding MS form and function. Here, we investigate MS volume in conjunction with measures of MS shape and surface area in a large, diverse sample of modern humans. We test whether variation in MS volume is associated with predictable changes in MS shape (i.e., allometry) and investigate the influence of MS size-shape scaling on mucosal surface area dynamics.Materials and Methods: Measures of MS volume and surface area were obtained from computed tomographic (CT) scans of 162 modern human crania from three ancestral backgrounds-Equatorial Africa, Europe, and East Asia. 3D coordinate landmarks and linear measurements were also collected. Multivariate analyses were employed to test for associations between MS volume and other morphological variables.Results: Significant associations between MS volume and 3D shape were identified both across and within the subsamples. Variation in MS volume was found to predominantly relate to differences in MS height and width dimensions relative to MS length. This pattern of allometric scaling was found to differentially influence total mucosal surface area and the SAV ratio. Conclusion:This study suggests that variation in MS volume is disproportionately mediated by MS width and height dimensions. This finding has implications for hypotheses which structurally link MS morphology to craniofacial ontogeny and those which suggest that MS morphology may perform adaptive physiological functions.