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Abstract: The performance of InAlAs/InGaAs quantum well field effect transistors are subject to high impact ionization and band-to-band tunneling (BTBT) due to its narrow bandgap feature. In this work, the energy gap is engineered using strain and quantization techniques to increase the effective energy gap leading to low impact ionization and BTBT leakage current. It is shown that the impact ionization is reduced in 5 nm channel device as compared to 13 nm device with onset at approximately E geff/q. Also the band-to-band-tunneling current is reduced due to the increase in effective energy gap. We have also investigated the effects of quantum well engineering on the dc performance of InGaAs HEMTs. [Copyright &y& Elsevier]

Abstract: In this study, we report on a demonstration of hydrogen sensing at low temperature using SnO2 functionalized AlGaN/GaN high electron mobility transistors (HEMT). The SnO2 dispersion was synthesized via a hydrothermal method and selectively deposited on the gate region of a HEMT device through a photolithography process. The high electron sheet carrier concentration of nitride HEMTs provides an increased sensitivity relative to simple Schottky diodes fabricated on GaN layers. The morphology and crystalline properties of the SnO2-gate, together with the texture of the multilayer films on the device were investigated by SEM, HRTEM, EDS and XRD. The effects of annealing treatment on the crystalline properties of the SnO2-gate, and gas sensing properties of SnO2-gated HEMT sensors were studied. The SnO2-gated HEMT sensor showed fast and reversible hydrogen gas sensing response at low temperature. [Copyright &y& Elsevier]

Abstract: The effects of atomic hydrogen and polyimide passivation on R0A product of type-II InAs/GaSb superlattice photo detectors for cut-off wavelength of both 6.5μm and 12μm were investigated. Low temperature current–voltage measurement shows that the use of atomic hydrogen during molecular beam epitaxy growth can improve R0A product by 260% for 6.5μm cut-off superlattice diodes and by 50% for 12μm cut-off ones. The R0A product of polyimide-passivated diodes with 12μm cut-off is about 80% higher than those un-passivated ones. Wannier–Stark oscillations at higher reverse bias were observed for polyimide-passivated superlattice diodes with 12μm cut-off. No Wannier–Stark oscillations were observed for un-passivated superlattice diodes, indicating that surface leakage current dominates in un-passivated diodes, while intrinsic dark current mechanisms such as tunneling and diffusion current dominate in polyimide-passivated diodes. [Copyright &y& Elsevier]

The impact of electron injection on the minority carrier diffusion length was studied at various temperatures in p-type Mg-doped GaN, Al0.2Ga0.8N, and Al0.2Ga0.8N/GaN superlattices, which were homogeneously and modulation (barrier only) doped. The activation energies for the electron injection-induced effect were found to be in the range from 190 to 260 meV, which is close to the thermal ionization energy of the Mg-acceptor. The obtained results are in agreement with the previously proposed model of minority carrier transport enhancement due to charging of Mg-centers in p-(Al)GaN. The activation energy of the electron injection effect observed in Al0.2Ga0.8N is consistent with the deepening of Mg-acceptor level due to the incorporation of Al into GaN lattice. The activation energy in the Al0.2Ga0.8N/GaN superlattice, homogeneously doped with Mg, indicates that the main contribution to the effect comes from the capture of injected electrons by the wells. [Copyright &y& Elsevier]

Competing Interests: The authors declare no conflicts of interest.

Competing Interests: The authors declare no conflicts of interest.

Background: Patients who understand their diagnosis and treatment are more likely to be satisfied with their care and more compliant with treatment. Dermatologic surgery is a specialized field with associated jargon that many patients may not understand., Objective: The aim of the study was to assess patient understanding of dermatology medical terminology., Methods: This was a single-blinded study conducted with patients 18 years and older from an academic dermatology clinic surveying patients on 12 terms that are frequently used in dermatologic surgery. Participants rated their level of confidence in their understanding of each term using a 5-point Likert scale, followed by explaining the definition of the term. 3 blinded physicians graded each participant’s definition using a 5-point scale of accuracy of understanding, designed to mimic the Likert scale., Results: A total of 200 respondents completed the survey (96% response rate). The average term perceived understanding was 3.90 ±0.66, the average term accuracy was 3.26±0.93. Patients overestimated their understanding 44% of the time, and underestimated their knowledge 17% of the time. The terms with the lowest respondent confidence were the terms secondary intention, Mohs, and flaps. The terms with the lowest respondent accuracy was secondary intention, defect, and Mohs surgery., Conclusion: There is a gap in knowledge in commonly used dermatologic surgery terms among patients. Certain demographics appear to be more at risk for not understanding medical jargon or overestimating their understanding of terms. Obtaining these patient demographics may help to identify patients needing additional education regarding dermatologic surgery. J Drugs Dermatol. 2021;20(11):1252-1254. doi:10.36849/JDD.6174.

Background: Histopathologic distinction between keratoacanthoma (KA) and squamous cell carcinoma (SCC) is challenging. We surmised that a discriminatory immunostain would be clinically meaningful. Previous investigators have found CD123-positive plasmacytoid dendritic cells (PDCs) are more prominent in KA than SCC. We sought to determine if CD123 immunostaining might have value as a diagnostic test for distinguishing KA from SCC., Methods: We used blinded, semi-automated image analysis to compare CD123 expression in 66 KAs and 63 SCCs in a tissue microarray., Results: PDCs were present in both KA and SCC. Mean PDC frequency was higher in KA than SCC (14.2 vs 11.2 mean cells/0.0945 square mm) but the difference was not statistically significant (P = 0.1240). There was no significant difference in mean PDC cluster frequency, mean intratumoral PDC frequency, or the percentage of PDCs as proportion of the total mononuclear inflammatory cell infiltrate between KA and SCC., Conclusion: CD123 immunostaining is not a clinically useful test for distinguishing KA from SCC., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: The aim of this study was to apply and evaluate three ultrasound methods to measure the bladder wall in a healthy population using high-resolution applications and to establish reference points and baselines for future research into lower urinary tract diseases, specifically to understand how lower urinary tract disorders affect the bladder wall and to find objective, non-invasive diagnostic tests., Methods: The study was conducted on 116 healthy volunteers aged 19-79 years old with approximately 10 participants in each decade group., Results: The following bladder parameters were recorded and measured using a GE LOGIQ E9 XDclear 2.0 ultrasound machine (GE Healthcare, Wauwatosa, WI, USA):Full bladder wall thickness (BWT) and each of three bladder wall layers thickness (BWLT) - serosa, detrusor and mucosa;Shear Wave Velocity (SWV) in m/s, using 2D Shear Wave Elastography (2D-SWE); andBladder wall blood circulation (Resistive Index, RI), using Duplex Doppler ultrasound.All of the above measurements were recorded at three different urine filling volumes: V0 (20-50 mL), V2 (180-200 mL) and V4 (380-400 mL) with ten repeats for each measured parameter. As expected, BWT and BWLT correlated inversely with increasing bladder volume. While there are no large differences in the healthy bladders of men compared with women, or with age, some small, but statistically significant, differences revealed. BWT at V0 is greater in men, as is the detrusor thickness at VO, but there are no differences at other volumes or for other layers. There is a small, but statistically significant thickening of BWT and detrusor layer and increase in SWV with age in men at V0. SWE showed increase in SWV measured at 400 mL bladder volume across all gender and age groups. There was no change in bladder wall vessels RI with age, between gender groups or increasing bladder volume., Conclusion: We used three ultrasound applications to obtain bladder wall reference data in healthy individuals and investigated the relationships between BWT, BWLT, SWV, RI and gender, age at three bladder volumes, for further studies into identifying and diagnosing different urinary bladder disorders. With further research, ultrasound could be used as a diagnostic test to differentiate bladder pathology in clinical practice., Competing Interests: The authors report no conflicts of interest in this work., (© 2019 Volikova et al.)

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