Measurement of Skull Size on Computed Tomography Images for Developing a Bone Conduction Headset Suitable for the Korean Standard Head Size.

BACKGROUND AND OBJECTIVES: We aimed to measure the head dimensions on computed tomography (CT) images, to compare them to directly measured head dimensions, and to predict a new parameter of bone thickness for aiding bone conduction implant (BCI) placement. SUBJECTS AND METHODS: We reviewed the facial and mandibular bone CT images of 406 patients. Their head sizes were analyzed using five parameters included in the 6th Size Korea project, and they were divided into age groups (ranging from the 10s to the 80s). We compared the head length, head width, sagittal arc, bitragion arc, and head circumference in the CT and Size Korea groups. We also added the parameter bone thickness for aiding BCI placement. RESULTS: All the head size parameters measured using CT were significantly smaller than those measured directly, with head length showing the smallest difference at 7.85 mm. The differences in the other four parameters between the two groups according to patient age were not statistically significantly different. Bone thickness had the highest value of 4.89±0.93 mm in the 70s and the lowest value of 4.10±0.99 mm in the 10s. Bone thickness also significantly correlated with head width (p=0.038). CONCLUSIONS: Our findings suggested that the CT and direct measurements yielded consistent data. Moreover, CT enabled the measurement of bone sizes, including bone thickness, that are impossible to measure directly. CT measurements may complement direct measurements in the Size Korea data when used for developing bone conduction hearing devices (BCIs and headsets) for the Korean population.

Design of wavelet-based ECG detector for implantable cardiac pacemakers.

A wavelet Electrocardiogram (ECG) detector for low-power implantable cardiac pacemakers is presented in this paper. The proposed wavelet-based ECG detector consists of a wavelet decomposer with wavelet filter banks, a QRS complex detector of hypothesis testing with wavelet-demodulated ECG signals, and a noise detector with zero-crossing points. In order to achieve high detection accuracy with low power consumption, a multi-scaled product algorithm and soft-threshold algorithm are efficiently exploited in our ECG detector implementation. Our algorithmic and architectural level approaches have been implemented and fabricated in a standard 0.35 µm CMOS technology. The testchip including a low-power analog-to-digital converter (ADC) shows a low detection error-rate of 0.196% and low power consumption of 19.02 µW with a 3 V supply voltage.

Effect of ashing conditions and optimization of nano process integration in copper/porous low-k nano-interconnects.

We report the optimization of ashing conditions and the process integration of a chemical vapor deposition (CVD) ultra low-k (k = 2.2) organosilicate (OSG) dielectric in a top hard mask damascene structure. The N2/H2 ash showed the lowest resistance-capacitance (RC) product and a dual top hard mask approach for dual damascene processing was built, using 200 nm SiC/50 nm SiO2 as the hard mask. This CVD low-k material had no low-k voiding, unlike other spin-on dielectric (SOD) low-k materials. The presence of the densified layer around the trench during the ashing process could improve the precursor penetration during the CVD barrier metal deposition process.

Development of bio-nanowire networks using phage-enabled assembly for biological sensor application.

This paper proposes a new approach to detect an electrochemical reaction using a working area consisting of bio-nanowires from genetically modified filamentous phages and nanoparticles. Use of the nanomaterials on the working electrode is a vital consideration in biological sensor development, because the biosensor sensitivity heavily depends on the material used. Here we use that fd-tet p8MMM filamentous phages displaying the MMM peptide on the major coat protein pVIII (designated p8MMM phages) were immobilized on the active area of an electrochemical sensor through chemical binding. The bio-nanowires composed of p8MMM phages and silver nanoparticles facilitated sensitive, rapid detection of particular molecules. We performed the experiment for observing electrochemical glucose detection to estimate the possibility of using one or other characterized-biological sensor. The current response of the bio-nanowire sensor reached sufficiently high signals at various glucose concentrations (10(-7) to 10(-4)M). The cyclic voltammetry peak current I(p) and peak potential E(p) were 689microA/cm(2) and 280mV, respectively. The filamentous nanophage-based electrode displayed a high sensitivity and good stability under various pH and temperature in enzyme determination. As a result, it may have wide application in analytical systems, label-free detection and biological sensors.