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Geometric diodes (GDs) represent a relatively unconventional class of diode that produces an asymmetric current response through carrier transport in an asymmetric geometry. Synthesized from the bottom up, Si nanowire‐based GDs are three‐dimensional, cylindrically symmetric nanoscale versions capable of room‐temperature rectification at GHz‐THz frequencies with near zero‐bias turn‐on voltages. Here, by fabricating three‐terminal n‐type Si nanowire GDs with axial contacts and an omega‐gate electrode, a distinct class of reconfigurable self‐switching geometric diodes (SSGDs) is reported. Single‐nanowire SSGD device measurements demonstrate a significant dependence of diode current and polarity on gate potential, where the diode polarity reverses at a gate potential of ≈−1 V under specific grounding conditions. Finite‐element modeling reproduces the experimental results and reveals that the gate potential—in combination with the morphology and dopant profile—produces an asymmetric potential along the nanowire axis that changes asymmetrically with axial bias, altering the effective conductive channel within the nanowire to yield diode behavior. The self‐switching effect is retained in two‐terminal SSGD devices, and modeling demonstrates that both three‐terminal and two‐terminal devices support rectification through THz frequencies. The results reveal a new mechanism of operation for nanowire‐based GDs and characterize a new type of self‐switching diode with reconfigurable polarity. [ABSTRACT FROM AUTHOR]

Introduction: Past studies have shown mixed results about the accuracy of store-and-forward (SAF) teledermatology in the evaluation of skin lesions. The objective of this study is to determine the accuracy of SAF teledermatology in the diagnosis of skin lesions and biopsy decision compared to in-person clinical evaluation. Methods: Histories and photographs of skin lesions gathered at clinic visits were sent as SAF consults to teledermatologists, whose diagnoses and biopsy decisions were recorded and compared statistically to the clinic data. Results and Discussion: We enrolled 206 patients with 308 lesions in the study. The study population was composed of 50% males (n = 104), and most patients were white (n = 179, 87%) and not Hispanic/Latino (n = 167, 81%). There was good concordance for biopsy decision between the clinic dermatologist (CD) and teledermatologist (TD) (Cohen's kappa (κ) = 0.51), which did not significantly differ when melanocytic lesions were excluded (κ = 0.54). The sensitivity and specificity of teledermatology based on biopsy decision was 0.71 and 0.85, respectively. Overall concordance in first diagnosis between the CD and TD was good (κ = 0.60). While there was no difference between CD and TD in proportion of correct diagnoses compared to histopathology, two skin cancers presentations were missed by TD. Study limitations included sample size, enrolment bias and differing amounts of teledermatologist case experience. Teledermatology has good concordance in diagnosis and biopsy decision when compared to clinic dermatology. Teledermatology may be utilized in the evaluation of skin lesions to expand access to dermatologic care. [ABSTRACT FROM AUTHOR]

Background: Oropharyngeal cancers associated with high-risk human papillomavirus (HR-HPV) infection are increasing in the United States, especially among men. We evaluated the prevalence and predictors of concurrent (genital and oral) and concordant (same-type) HR-HPV infections in the United States.Methods: We used the National Health and Nutrition Examination Survey from 2009 to 2016. Predictors were assessed via multivariable logistic regression.Results: Among 10 334 respondents, 172 (2.1%) had concurrent infections (109 [3.5%] men and 63 [0.76%] women]. Ninety-three (1.0%) had concordant infections (54 [1.6%] men and 39 [0.5%] women). Predictors of concurrence in men included the following: no longer married versus married (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.3-4.9), living with a partner versus married (3.0; 1.2-7.5), and having 2-5 lifetime oral sex partners (3.0; 1.2-7.5). In women they included the following: no longer married versus married (3.6; 1.3-10.3), ≥2 recent sex partners (4.6; 1.4-15.6 for 2-5 partners and 3.9; 1.1-14.3 for ≥6 partners), and marijuana use (2.2; 1.0-4.5). The predictor of concordance in men and women was no longer married versus married (3.5; 1.2-9.9 in men and 3.2; 1.1-9.4 in women).Conclusions: Concurrent and concordant HR-HPV infections occur at a high rate, especially among men, and are associated with behavioral factors. This underscores the importance of HPV vaccination, screening, and education in men. [ABSTRACT FROM AUTHOR]