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PurposeTo describe the differences in a range of quantitative OCT angiography (OCTA) metrics across early stages of diabetic retinopathy (DR), providing robust effect estimates as well as sensitivity and specificity.DesignCross-sectional study with population-based sampling.ParticipantsFour hundred forty-one eyes from 296 individuals: 328 control eyes (no diabetes mellitus [DM] and no DR), 55 eyes with DM and no DR, and 58 eyes with early nonproliferative DR.MethodsMultimodal retinal imaging included color fundus photography, color Optomap ultra-widefield imaging, and spectral-domain OCT (Spectralis OCT2; Heidelberg Engineering GmbH) with the OCTA module. All images were graded for the presence and severity of DR features. OCTA images were assessed manually for inclusion based on quality. Binary OCTA metrics were assessed after 3-dimensional projection artifact removal including from the nerve fiber layer vascular plexus, superficial vascular plexus (SVC), and deep vascular plexus (DVC) by Early Treatment Diabetic Retinopathy Study (ETDRS) grid, foveal avascular zone (FAZ) area, FAZ minimum and maximum diameter, perimeter length, and circularity.Main Outcome MeasuresDiabetes mellitus and DR status and presence or absence of DR in the retinal periphery.ResultsThe reduction in vessel densities in participants with DM and manifest DR compared with control participants tended to be twice that of those with DM, but no DR, compared with control participants. Some evidence of spatial heterogeneity in vessel reductions was found in those yet to develop DR, whereas those with manifest DR had significant reductions across the ETDRS grid. The FAZ perimeter and circularity were impacted most significantly by DM, and those with DR showed decreased multispectral fractal dimensions compared with control participants. Eyes with peripheral DR had reduced vessel density compared with those with DM and no DR only in the superior outer, temporal inner, and temporal outer regions in the DVC and SVC. The area under the receiver operating characteristic curve ranged between 0.48 and 0.73.ConclusionsSignificant differences in OCTA metrics can be found in those with DM before manifest DR using commercially available equipment with minimal image postprocessing. Although diagnostic performance was poor, these metrics may be useful for measuring change over time in clinical trials.

A simple passive capacitance model has been optimized to predict breakdown in a stacked SOI FET. Specifically, as the number of FETs in a switch increases, an equivalent increase in breakdown is not seen in hardware; instead, the breakdown performance saturates as the number of stacks in the FET increases. This phenomenon is not predicted by the FET foundry model. This work is focused on FETs for RF switches in flip chip topologies. As a result of this work, the different components that contribute to off-state capacitances were also described which is important for model development and accuracy.

INTRODUCTION Cataract surgery is the most frequently performed surgery in the Veterans Health Administration (VHA). A well-known complication is a transient but potentially harmful elevation in intraocular pressure (IOP) within the 24-h postoperative period. The purpose of this study is to investigate the risk factors for IOP elevation 1 d after cataract surgery in a cohort of United States (US) veterans. MATERIALS AND METHODS The study included 784 patients who underwent cataract surgery between April 2013 and April 2016 at a single Veterans Affairs medical center in Providence, RI. One thousand one hundred thirty-seven cataract surgeries were considered in total. Institutional Review Board (IRB) approval was obtained through the Providence Veterans Affairs Medical Center (PVAMC). Logistic regression, adjusted for patients with bilateral surgeries, was used to evaluate risk factors for first postoperative day IOP elevation (≥28 mmHg). The main outcome measure was elevated IOP on postoperative day 1 (POD1) after cataract surgery. RESULTS The average patient age was 74 yr. Ninety-eight percent (1,110/1,137) of cases involved male patients; 75.3% (856/1,137) of the cataract surgeries were performed by resident surgeons. Type II diabetes mellitus (DM) was present in 41% (461/1,137), alpha-1 blocker use in 31% (358/1,137), ocular hypertension (ocular HTN) in 4% (44/1,137), and glaucoma in 11% (126/1,137) of cases. Twenty-two percent (232/1,137) of eyes had elevated IOP. Independent risk factors were a history of ocular HTN (OR: 8.74 [4.03-18.9]), glaucoma (OR: 3.54 [2.17-5.75]), a preoperative IOP ≥22 mmHg (OR: 2.51 [1.12-5.62]), and complicated cataract surgery (OR: 2.45 [1.18-5.08]), defined as vitreous loss, anterior capsular tear (ACT), posterior capsular tear (PCT), or presence of zonular lysis. CONCLUSION These findings suggest that cataract surgery patients with ocular HTN, glaucoma, a preoperative IOP ≥22 mmHg, or significant intraocular complications may benefit from prophylactic ocular anti-hypertensive medication.

In this paper, parallel plate varactor based phase shifter circuits using Barium Strontium Titanate (BST) thin films are presented. A cascade of 10, 15 and 20 parallel plate varactors were able to produce (150°, 258°, 297°), (218°, 381°,443°) and (227°, 402°, 464°) phase shift at (5, 10, 12 GHz) respectively. The 360° phase shift is achieved with small device size, low bias voltages (0-8 V), low leakage currents, low insertion loss and high figure of merit (FOM). FOM of 40, 33, 24 Degrees/dB is achieved with 10, 15 and 20 shunt varactors at 12 GHz respectively. The proposed circuit is very easy to fabricate which uses a CPW transmission line configuration and can be easily integrated with other circuits on chip.

In environmental epidemiology, measurements of exposure biomarkers often fall below the assay's limit of detection. Existing methods for handling this problem, including deletion, substitution, parametric regression, and multiple imputation, can perform poorly if the proportion of "nondetects" is high or parametric models are mis-specified. We propose an approach that treats the measured analyte as the modeled outcome, implying a role reversal when the analyte is a putative cause of a health outcome. Following a scale reversal as well, our approach uses Cox regression to model the analyte, with confounder adjustment. The method makes full use of quantifiable analyte measures, while appropriately treating nondetects as censored. Under the proportional hazards assumption, the hazard ratio for a binary health outcome is interpretable as an adjusted odds ratio: the odds for the outcome at any particular analyte concentration divided by the odds given a lower concentration. Our approach is broadly applicable to cohort studies, case-control studies (frequency matched or not), and cross-sectional studies conducted to identify determinants of exposure. We illustrate the method with cross-sectional survey data to assess sex as a determinant of 2,3,7,8-tetrachlorodibenzo-p-dioxin concentration and with prospective cohort data to assess the association between 2,4,4'-trichlorobiphenyl exposure and psychomotor development.

Due to their excellent electrical, optical, and mechanical properties, nanosized single wall carbon nanotubes (SWNTs) have attracted significant attention as a transducing element in nano-bio sensor research. Controlled assembly, device fabrication, and bio-functionalization of the SWNTs are crucial in creating the sensors. In this study, working biosensor platforms were created using dielectrophoretic assembly of single wall carbon nanotubes (SWNTs) as a bridge between two gold electrodes. SWNTs in a commercial SDS surfactant solution were dispensed in the gap between the two gold electrodes, followed by applying an ac voltage across the two electrodes. The dielectrophoresis aligns the CNTs and forms a bridge between the two electrodes. A copious washing and a subsequent annealing of the devices at 200 ᵒC remove the surfactants and create an excellent semiconducting (p-type) bridge between the two electrodes. A liquid gated field effect transistor (LGFET) was built using DI water as the gate dielectric and the SWNT bridge as the channel. Negative gate voltages of the FET increased the drain current and applying a positive gate voltage of +0.5V depleted the channel of charges and turned the device off. The biosensor was verified using both the two terminal and three terminal devices. Genomic salmon DNA dissolved in DI water was applied on the SWNT bridge in both type of devices. In the two terminal device, the conductance of the bridge dropped by 65x after the binding of the DNA. In the LGFET, the transconductance of the device decreased 2X after the binding of the DNA. The binding of the DNA also suppressed hysteresis in the Drain Current vs Gate Voltage characteristics of the LGFET.