Dietary exposure assessment of infants to bisphenol A from the use of polycarbonate baby milk bottles

The residual bisphenol A (BPA) levels in 28 different brands of polycarbonate (PC) baby milk bottles available in the Singapore market were measured. With a detection limit of 3 mg/kg, BPA residues were detected in 19 out of the 28 PC baby milk bottles at levels between 4.01 and 141 mg/kg, with a mean of 28.1 ± 31.4 mg/kg and a median of 17.2 mg/kg. The potential migration of BPA from each of the 28 PC milk bottles was also measured using food-simulating solvents and time conditions recommended by the US Food and Drug Administration (US FDA), but using temperatures more severe than actual use. The highest upper-bound mean BPA migration levels of 0.64 ± 0.48 µg/in² in 10% ethanol at 70°C and 0.43 ± 1.25 µg/in² in corn oil at 100°C were observed after incubating cut portions of the milk bottles for 240 h. With this migration data and using US FDA's procedure for estimation of dietary exposure, the worst-case dietary exposure assessment for the intake of BPA by infants between birth and three months of age was below the oral Reference Dose of 0.05 mg/kg bw/day established by the US Environmental Protection Agency. This study showed that the dietary exposure to BPA from actual uses of PC milk bottles is unlikely to pose a health risk in infants.     

Real-time computation of photic extremum lines (PELs)

Photic extremum lines (PELs) are view-dependent, object-space feature lines that characterize the significant changes of surface illumination. Though very effective for conveying 3D shapes, PELs are computationally expensive due to the heavy involvement of the third- and fourth-order derivatives. Also, they require the user to manually place a few auxiliary lights to depict the model details, which is usually tedious work. To overcome these challenges, we present a novel computational framework that improves both the speed and quality of PELs. First, we derive a simple, closed-form formula of gradient operator such that various orders of derivatives can be computed efficiently and in parallel using graphics processing units (GPUs). The GPU-based PEL extraction algorithm is one order of magnitude faster than the original one. Second, we propose to extract PELs from various non-photorealistic shadings that not only depict the overall shape but also bring out the details at different frequencies simultaneously. As a result, the user can easily control the relative emphasis to different scales and obtain the desired line drawing results. We demonstrate the improved PELs on a wide range of real-world objects.     

Modelling of surface nanoparticle inclusions for nanomechanical measurements by an AFM or nanoindenter: spatial issues

Finite element analysis (FEA) is used to model nanoindentation by a rigid, spherically shaped indenter, axially indenting an elastic two phase polymer system comprised of a cylindrical nanoparticle of compliant polymer set in a semi-infinite matrix of stiffer polymer. The cylindrical nanoparticle is normal to the sample surface. An axisymmetric finite element model is used to determine the reduced modulus measured as a function of the indentation depth for various nanoparticle radii and extensions below the surface. We show how the previous simple analytical equations may be extended to describe these situations with accuracy. This gives excellent agreement with the FEA and provides a clear guide to the maximum indentation depth as a function of both the nanoparticle radius and its thickness consistent with a choice of either computation from the analytical equations or direct measurement with a maximum of 10% error in the measured reduced modulus.     

Modeling of the body current in a Bi-MOS hybrid-mode environment

The body current I_B of deep submicron lightly doped drain pMOSFETs has been investigated. Based on the experimental results, an analytical I_B model, applicable for devices operating in a Bi-MOS hybrid-mode environment, has been developed for the first time. The proposed model is able to effectively characterize the measured I_B results over a wide range of independently applied biases (gate, drain and body) and gate lengths (from 1 μm down to 0.25 μm). The possibility of minimizing or even eliminating the undesired I_B is also explored and discussed for the first time.     

Computer-assisted coloring by matching line drawings

An approach to automatically color line drawings based on feature matching is proposed. The motivation is that coloring 2D animation is still a labor-intensive process in current cartoon film production. The objective of our work is to investigate how to automatically color an image in a cartoon sequence on the basis of the previous frame. Our method first establishes the matching relationship of two images, after which it automatically paints one of them with the color information of the other using a region-matching algorithm. The region-matching algorithm is based on feature correspondences. The results show that the proposed algorithm can straightforwardly and robustly realize our objective and has a promising future for our next step to further automate conventional animation.     

Random polling scheme with priority

A random polling scheme which has an inherent priority structure is proposed. The priority structure is implemented by appropriate choice of the polling table. Numerical results for the case of no load show that the priority scheme is effective and the mean no-load token cycle time can be tailored to the priority of the station.<>     

Rendering fireworks displays

A particle system technique to model, render, and animate realistic fireworks displays is presented. The attributes of the fireworks display that the particle system models are color, brightness, shape, trial, size, particle dynamics, blinking, mousing, star effect, spinning, and elasticity. A rendering engine that consists of various modules which individually handle a particular property of the particle is described     

Measurement‐based link scheduling for maritime mesh networks with directional antennas

The proliferation of wireless transceivers and the availability of the unlicensed band has given a boost to the deployment of wireless networks, with IEEE802.11/WiFi being the major driver in this arena. In this research, we consider a wireless mesh network designed for long‐distance communication with a typical deployment scenario of a maritime mesh network. This network uses an antenna system made up of multiple fixed‐beamwidth antennas. Compared to most other directional antenna schemes which use directional antenna for transmission and omni‐directional antenna for reception, our system uses directional antennas for both transmission and reception where a pair of transmitter–receiver antennas needs to be aligned and have an acceptable channel quality before transmission can take place. Through efficient use of directional antennas for both transmission and reception, and spatial reuse in transmission, we are able to realize a high‐capacity mesh network. In this paper, we present a practical approach to achieve contention‐free medium access, namely, a measurement‐based link‐scheduling algorithm. We evaluate the performance of the link‐scheduling algorithm using simulations and show that it is able to exploit the spatial diversity provided by the directional antennas to outperform comparable schemes for wireless mesh networks. We also briefly discuss implementation issues to demonstrate the viability of the approach. Copyright © 2010 John Wiley & Sons, Ltd.     

In-Situ X-Ray Studies of Cocoa Butter Droplets Undergoing Simulated Spray Freezing

Spray freezing offers a novel manufacturing route to fine powders with controlled crystalline structures. Here we simulate this process by freezing (using a cold dry air flow) suspended 2-mm diameter droplets of cocoa butter such that X-ray diffraction observation of the droplet’s evolving crystalline structure is possible in situ. Initially the Form I polymorph is observed in the droplets: this transforms to Form II over a few minutes and then to Form III over a few hours, even at 0 °C. If the droplet is then warmed to 24 °C, further transformation to Form IV and then Form V occur over approximately 2 h. These phase transformations are similar to those which would be expected in a bulk cocoa butter sample, but occur significantly faster in the droplets. Small crystal sizes in the frozen droplet, resulting from the droplet’s low Biot number (and thus even temperature distribution), is postulated as being the cause for the unexpectedly rapid evolution in the crystal habit.     

Feature- and region-based auto painting for 2D animation

This paper presents a novel approach to automating the entire coloring process in traditional cel animation production. A feature-based region-matching algorithm is proposed. It first matches a set of master frames to construct correspondences between regions in the master frames and extract a stable topology. The first frame of each scene is then colored based on the set of master frames. With the painted first frame and established stable topology, each region in subsequent frames is matched with regions in the previous frames and colored. Compared with other algorithms, our approach is able to handle bigger changes between frames and automatically color the first frame of each sequence.