The role of cleaning conditions and epitaxial layer structure on reliability of Sc2O3 and MgO passivation on AlGaN/GaN HEMTS

2002 ◽  
Vol 46 (12) ◽  
pp. 2185-2190 ◽  
Author(s):  
B Luo ◽  
R.M Mehandru ◽  
Jihyun Kim ◽  
F Ren ◽  
B.P Gila ◽  
...  
Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2152
Author(s):  
Fernando C. Baltanás ◽  
Cynthia Mucientes-Valdivieso ◽  
L. Francisco Lorenzo-Martín ◽  
Natalia Fernández-Parejo ◽  
Rósula García-Navas ◽  
...  

Prior reports showed the critical requirement of Sos1 for epithelial carcinogenesis, but the specific functionalities of the homologous Sos1 and Sos2 GEFs in skin homeostasis and tumorigenesis remain unclear. Here, we characterize specific mechanistic roles played by Sos1 or Sos2 in primary mouse keratinocytes (a prevalent skin cell lineage) under different experimental conditions. Functional analyses of actively growing primary keratinocytes of relevant genotypes—WT, Sos1-KO, Sos2-KO, and Sos1/2-DKO—revealed a prevalent role of Sos1 regarding transcriptional regulation and control of RAS activation and mechanistic overlapping of Sos1 and Sos2 regarding cell proliferation and survival, with dominant contribution of Sos1 to the RAS-ERK axis and Sos2 to the RAS-PI3K/AKT axis. Sos1/2-DKO keratinocytes could not grow under 3D culture conditions, but single Sos1-KO and Sos2-KO keratinocytes were able to form pseudoepidermis structures that showed disorganized layer structure, reduced proliferation, and increased apoptosis in comparison with WT 3D cultures. Remarkably, analysis of the skin of both newborn and adult Sos2-KO mice uncovered a significant reduction of the population of stem cells located in hair follicles. These data confirm that Sos1 and Sos2 play specific, cell-autonomous functions in primary keratinocytes and reveal a novel, essential role of Sos2 in control of epidermal stem cell homeostasis.


Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 784
Author(s):  
Shinji Okaniwa

The most important role of ultrasound (US) in the management of gallbladder (GB) lesions is to detect lesions earlier and differentiate them from GB carcinoma (GBC). To avoid overlooking lesions, postural changes and high-frequency transducers with magnified images should be employed. GB lesions are divided into polypoid lesions (GPLs) and wall thickening (GWT). For GPLs, classification into pedunculated and sessile types should be done first. This classification is useful not only for the differential diagnosis but also for the depth diagnosis, as pedunculated carcinomas are confined to the mucosa. Both rapid GB wall blood flow (GWBF) and the irregularity of color signal patterns on Doppler imaging, and heterogeneous enhancement in the venous phase on contrast-enhanced ultrasound (CEUS) suggest GBC. Since GWT occurs in various conditions, subdividing into diffuse and focal forms is important. Unlike diffuse GWT, focal GWT is specific for GB and has a higher incidence of GBC. The discontinuity and irregularity of the innermost hyperechoic layer and irregular or disrupted GB wall layer structure suggest GBC. Rapid GWBF is also useful for the diagnosis of wall-thickened type GBC and pancreaticobiliary maljunction. Detailed B-mode evaluation using high-frequency transducers, combined with Doppler imaging and CEUS, enables a more accurate diagnosis.


1991 ◽  
Vol 66 (1-4) ◽  
pp. 287-294 ◽  
Author(s):  
S. Duhalde ◽  
B. Arcondo ◽  
H. Sirkin

2017 ◽  
Vol 74 (1) ◽  
pp. 133-149 ◽  
Author(s):  
Sarah D. Ditchek ◽  
John Molinari ◽  
David Vollaro

Abstract The ERA-Interim is used to generate azimuthally averaged composites of Atlantic basin tropical cyclones from 1979 to 2014. Both the mean state and the eddy forcing terms exhibited similar radial–vertical structure for all storm intensities, varying only in magnitude. Thus, only major hurricanes are described in detail. Radial inflow and outflow extended beyond the 2000-km radius. Warm anomalies reached 2000 km in the outflow layer. Composite eddy momentum fluxes within the outflow layer were 2.5 times larger than mean momentum fluxes, highlighting the importance of outflow–environment interactions. A balanced vortex equation was applied to understand the role of eddy heat and momentum fluxes. Dominant terms were the lateral eddy heat flux convergence, lateral eddy momentum flux, and eddy Coriolis torque. Each acted to enhance the secondary circulation. The eddy momentum flux terms produced about twice the response of heat flux terms. The circulation created by the eddy Coriolis torque arises from a vertical gradient of mean storm-relative meridional wind in the upper troposphere at outer radii. It is produced by background inertial stability variations that allow stronger outflow on the equatorward side. Overall, the fluxes drive a strengthened secondary circulation that extends to outer radii. Balanced vertical motion is strongest in the upper troposphere in the storm core. A method is proposed for evaluating the role of environmental interaction on tropical cyclone intensity change.


ACS Omega ◽  
2018 ◽  
Vol 3 (9) ◽  
pp. 11340-11353 ◽  
Author(s):  
Inderbir S. Sidhu ◽  
Amalie L. Frischknecht ◽  
Paul J. Atzberger

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