Reactive ion etching of gallium nitride using hydrogen bromide plasmas

The characteristics of the reactive ion etching (RIE) of gallium nitride (GaN) have been investigated using HBr, 1:1 HBr:Ar, and 1:1 HBr:H2 plasmas. Etch rates were found to increase with plasma self-bias voltage for all gas mixtures exceeding 60 nm/min at -400V for pure HBr. Higher etch rates were obtained for pure HBr than for HBr mixtures with Ar and H2. Chamber pressure was also found to slightly affect etch rates for the pressure ranges investigated. The anisotropy of etched profiles was found to improve with increasing pressure. Smooth etched surfaces are also demonstrated.link_to_subscribed_fulltex

Intermuscular adipose tissue and its relationship to metabolic risk factors

Artículo 1°: Aplicar la sanción de expulsión para el estudiante xxxx xxxx

Adipose tissue in muscle: a novel depot similar in size to visceral adipose tissue

BACKGROUND: The manner in which fat depot volumes and distributions, particularly the adipose tissue (AT) between the muscles, vary by race is unknown. OBJECTIVE: The objective was to quantify a previously unstudied and novel intermuscular AT (IMAT) depot and subcutaneous AT, visceral AT (VAT), and total-body skeletal muscle mass in healthy sedentary African American (AA), Asian, and white adults by whole-body magnetic resonance imaging. IMAT is the AT between muscles and within the boundary of the muscle fascia. DESIGN: Analyses were conducted on 227 women [AA (n = 79): body mass index (BMI; in kg/m(2)), 29.0 +/- 5.5; age, 45.7 +/- 16.9 y; Asian (n = 38): BMI, 21.7 +/- 2.9; age, 47.2 +/- 19.9 y; whites (n = 110): BMI, 24.9 +/- 5.4; age, 43.7 +/- 16.2 y]) and 111 men [AA (n = 39): BMI, 25.6 +/- 3.2; age, 45.5 +/- 18.8 y; Asian (n = 13): BMI, 24.9 +/- 2.5; age, 45.6 +/- 25.0 y; white (n = 59): BMI, 25.8 +/- 3.8; age 44.5 +/- 16.3 y]. RESULTS: IMAT depots were not significantly different in size between race groups at low levels of adiposity; however, with increasing adiposity, AAs had a significantly greater increment in the proportion of total AT (TAT) than did the whites and Asians (58, 46, and 44 g IMAT/kg TAT, respectively; P = 0.001). VAT depots were not significantly different in size at low levels of adiposity but, with increasing adiposity, VAT accumulation was greater than IMAT accumulation in the Asians and whites; no significant differences were observed in AAs. CONCLUSION: Race differences in AT distribution extend to IMAT, a depot that may influence race-ethnicity differences in dysglycemi

Modeling and Simulation of Fiber Image Guide Multi-Chip Modules for MOEMS Applications

Densely integrated systems in the future will incorporate device and communication technologies that span the domains of digital and analog electronics, optics, micro-mechanics, and micro-fluidics. Given the fundamental differences in substrate materials, feature scale and processing requirements between integrated devices in these domains, it is likely that multi-chip, system-in-package, integration solutions will be required for the foreseeable future. The multi-domain nature of these systems necessitates design tools that span multiple energy domains, time and length scales, as well as abstraction levels. This paper describes a case study of the modeling of a photonic/multi-technology system based on a 3D volumetric packaging technology implemented with Fiber Image Guide (FIG) based technology. It is 64x64 fiber crossbar switch implementation using three Silicon-on-Sapphire mixed signal switch die with flip-chip bonded VCSEL and detector arrays. We show a single end-to-end system simulation of the O/E crossbar working across the domains of free-space and guided wave optical propagation, GaAs O/E and E/O devices, analog drivers and receivers and integrated digital control