Hepatitis B virus (HBV) infection in the US is the most common among Asians followed by non-Hispanic blacks. However, there have been few studies that describe HBV infection and immunity by racial group. Our study aims to assess racial/ethnic disparities in the prevalence and awareness of HBV infection and immunity using nationally representative data. In the National Health and Nutrition Examination Survey 2011–2014, 14,722 persons had HBV serology testing. We estimated the prevalence of HBV infection, past exposure, and immunity by selected characteristics and calculated adjusted odds ratios using survey-weighted generalized logistic regression. Awareness of infection and vaccination history was also investigated. The overall prevalence of chronic HBV infection, past exposure, and vaccine-induced immunity was 0.34% [95%CI 0.24–0.43], 4.30% [95%CI 3.80–4.81], and 24.4% [95%CI 23.4–25.4], respectively. The prevalence of chronic infection was 2.74% [95% CI 1.72–3.76] in Asians, 0.64% [95% CI 0.35–0.92] in non-Hispanic blacks, and 0.15% [95% CI 0.06–0.24] in non-Asian, non-blacks. Only 26.2% of those with chronic infection were aware of their infection. The prevalence of the past exposure was 21.5% [95%CI 19.3–23.7] in Asians, 8.92% [95%CI 7.84–9.99] in non-Hispanic blacks, 2.05% [95%CI 1.49–2.63] in non-Hispanic whites, and 4.47% [95%CI 3.25–5.70] in Hispanics. Prevalence of vaccine-induced immunity by each race was 34.1% [95%CI: 32.0–36.2] in Asians, 25.5% [95%CI: 24.0–27.0] in non-Hispanic blacks, 24.0% [95%CI: 22.6–25.4] in non-Hispanic whites, and 22.2% [95%CI: 21.3–23.3] in Hispanics. There are considerable racial/ethnic disparities in HBV infection, exposure, and immunity. More active and sophisticated healthcare policies on HBV management may be warranted.

Non-obese NAFLD is more prevalent in women with polycystic ovary syndrome than in those without. In non-obese patients with polycystic ovary syndrome, hyperandrogenemia may be an independent risk factor for non-obese NAFLD.

The endorectal coil is being increasingly used in magnetic resonance imaging (MRI) and MR spectroscopic imaging (MRSI) to obtain anatomic and metabolic images of the prostate with high signal-to-noise ratio (SNR). In practice, however, the use of endorectal probe inevitably distorts the prostate and other soft tissue organs, making the analysis and the use of the acquired image data in treatment planning difficult. The purpose of this work is to develop a deformable image registration algorithm to map the MRI/MRSI information obtained using an endorectal probe onto CT images and to verify the accuracy of the registration by phantom and patient studies. A mapping procedure involved using a thin plate spline (TPS) transformation was implemented to establish voxel-to-voxel correspondence between a reference image and a floating image with deformation. An elastic phantom with a number of implanted fiducial markers was designed for the validation of the quality of the registration. Radiographic images of the phantom were obtained before and after a series of intentionally introduced distortions. After mapping the distorted phantom to the original one, the displacements of the implanted markers were measured with respect to their ideal positions and the mean error was calculated. In patient studies, CT images of three prostate patients were acquired, followed by 3 Tesla (3 T) MR images with a rigid endorectal coil. Registration quality was estimated by the centroid position displacement and image coincidence index (CI). Phantom and patient studies show that TPS-based registration has achieved significantly higher accuracy than the previously reported method based on a rigid-body transformation and scaling. The technique should be useful to map the MR spectroscopic dataset acquired with ER probe onto the treatment planning CT dataset to guide radiotherapy planning.

This work reports on the design and performance evaluation of a miniature direct methanol fuel cell ͑DMFC͒ integrated with an electro-osmotic ͑EO͒ pump for methanol delivery. Electro-osmotic pumps require minimal parasitic power while boasting no moving parts and simple fuel cell integration. Here, an electro-osmotic pump is realized from a commercially available porous glass frit. We characterize a custom-fabricated DMFC with a free convection cathode and coupled to an external electro-osmotic pump operated at applied potentials of 4.0, 7.0, and 10 V. Maximum gross power density of our free convection DMFC ͑operated at 50°C͒ is 55 mW/cm 2 using 4.0 mol/L concentration methanol solution supplied by the EO pump. Experimental results show that electro-osmotic pumps can deliver 2.0, 4.0, and 8.0 mol/L methanol/water mixtures to DMFCs while utilizing ϳ5.0% of the fuel cell power. Furthermore, we discuss pertinent design considerations when using electro-osmotic pumps with DMFCs and areas of future study.

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For the first time, the tradeoffs between drive current (I on ), intrinsic delay (τ), band-to-band tunneling (BTBT) leakage and short channel effects (SCE) have been systematically compared in futuristic high mobility channel materials, like strained-Si (0-100%), strained-SiGe (0-100%) and relaxed-Ge. The optimal channel materials and device structures for nanoscale p-MOSFETs are discussed through detailed BTBT (including band structure and quantum effects), Full-Band Monte-Carlo, 1-D Poisson-Schrodinger Simulations and Experiments on ultra-thin (<10nm) SOI FETs.Introduction High mobility channel materials like strained-Si, Ge and strained Si x Ge 1-x are very promising as future channel materials [1]- [8]. Currently, strained-Si is the dominant technology for high performance p-MOSFETs and increasing the strain provides a viable solution to scaling. However, looking into future nanoscale pMOSFETs, it becomes important to look at novel channel materials, like Ge or strained-SiGe, and device structures which may perform better than even very highly (100%) strained-Si. Most high mobility materials have a significantly smaller bandgap compared to Si and suffer from higher BTBT leakage, which may ultimately limit their scalability. In this work, through detailed detailed BTBT (including band structure and quantum effects), Full-Band Monte-Carlo and 1-D Poisson-Schrodinger simulations, and experiments performed on ultra-thin (<10nm) SOI FETs, we systematically compare different double-gate (DG) geometries and high mobility channel materials.Device Structures And Channel Materials A common terminology used in this paper is a channel material (x,y) where, x denotes the Ge content in the channel material and y denotes the Ge content in an imaginary relaxed (r) substrate to which the channel is strained (s). E.g. (0.3,0) is a s-SiGe (with 30% Ge content) channel strained to an underlying Si substrate. (0,0.6) is a sSi channel strained to a r-SiGe (60% Ge content) substrate. In this work, the s-Si was varied from (0,0) r-Si to (0,1) s-Si (100%) and the s-SiGe was varied from (1,1) r-Ge to (1,0) s-Ge (100%). Fig. 1(a)-(c) show the schematic of the device structures and materials that are investigated. 1(c) is a heterostructure device with a strained-SiGe channel that is sandwiched between two thin Si caps. The bandstructure for a (1,0) s-Ge heterostructure is shown in Fig. 2. The bandgaps (E G ), ladders and effective masses used in this work are taken from [9]-[10] and are tabulated in Table 1.BTBT Leakage Fig. 3 shows a typical Id-Vg characteristic of a p-MOSFET. The minimum achievable standby leakage (I OFF,MIN ) is at the intersection of the BTBT leakage with the subthreshold leakage. To accurately estimate I OFF,MIN for different materials, we performed detailed BTBT simulations, which take into account bandstructure information, quantum mechanical (QM) effects and the direct-indirect valley transitions. As seen in Fig. 4, the I OFF,MIN increases monotonically with increasing strain due to the rapid reduction in the E ...

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