among 880 studied feet of 7-14 years old children 6.9% suffered mild and severe flat foot. 53.8% of the affected children were symptomatic. as 40.1% of the general population experiences symptoms, in a small proportion of affected persons, symptoms are due to flat foot. the prevalence of symptoms rises with increasing severity of the disorder. in this article, reviewing general aspects of flat ...

An adaptive quantization algorithm for MPEG-2 video coding using neural network is presented in this paper. The proposed algorithm uses BP neural network to divide the macroblock activity into one of four categories: flat. edge. texture. fine-texture. and thus the macroblock can be quantized adaptively according to the human vision system (HVS) sensitivity. Experiment results show that this met...

Cell migration in a cultured neuronal network presents an obstacle to selectively measuring the activity of the same neuron over a long period of time. Here we report the use of nanopillar arrays to pin the position of neurons in a noninvasive manner. Vertical nanopillars protruding from the surface serve as geometrically better focal adhesion points for cell attachment than a flat surface. The...

By a combination of analytical and numerical techniques, we demonstrate the existence of spherical, asymptotically flat traversable wormholes supported by exotic matter whose stress tensor relative to the orthonormal frame of Killing observers takes the form of a perfect fluid possessing anisotropic pressures and subject to linear equations of state: τ = λρc, P = μρc. We show that there exists ...

By subjecting DNA aqueous solution to evaporate in a curve-on-flat geometry that was composed of either a spherical lens or a cylindrical lens situated on a flat substrate, a set of highly aligned DNA nanowires in the forms of spokes and parallel stripes over a macroscopic area (i.e., millimeter scale) were successfully created. The DNA molecules were stretched and aligned on polymer-coated sub...

Circular domains in phase-separated lipid vesicles with symmetric leaflet composition commonly exhibit three stable morphologies: flat, dimpled, and budded. However, stable dimples (i.e., partially budded domains) present a puzzle since simple elastic theories of domain shape predict that only flat and spherical budded domains are mechanically stable in the absence of spontaneous curvature. We ...

We study configurations of intersecting domain walls in a Wess-Zumino model with three vacua. We introduce a volume-preserving flow and show that its static solutions are configurations of intersecting domain walls that form double bubbles, that is, minimal area surfaces which enclose and separate two prescribed volumes. To illustrate this field theory approach to double bubbles, we use domain ...

In the colon of F344 rats treated with 2 x 15 mg/kg body weight of azoxymethane (AOM), the density (number of lesions/cm2/rat) of flat aberrant crypt foci (ACF) was 13-fold higher (p < 0.05) in the surface area of mucosa immediately adjacent to lymphoid follicles compared with the density of these lesions in the rest of the mucosa. A similar prevalent location near lymphoid follicles was observ...

Electrode contact impedance is a crucial factor in physiological measurements and can be an accuracy-limiting factor when performing electroencephalography and electrical impedance tomography. In this work, standard flat electrodes and micromachined multipoint spiked electrodes are characterized with a finite-element method electromagnetic solver and the dependence of the contact impedance on g...

Although a small point ultrasound transducer has a wide acceptance angle, its small active area leads to a high thermal-noise-induced electric voltage in the transducer, thus the sensitivity is low. By contrast, a finite-size flat transducer has high sensitivity, but the acceptance angle is small, which limits its application in reconstruction-based photoacoustic tomography (PAT). Here, we prop...