David Lim

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Biological cells are highly sensitive to variation in local pressure because cellular membranes are not rigid. Unlike microbeads, cells deform under pressure or even lyse. In isolating or enriching cells by mechanical filtration, pressure-induced lysis is exacerbated when high local fluidic velocity is present or when a filter reaches its intended capacity.(More)
Microfluidic systems can conveniently be used for rapid analysis of biological samples. Here we describe a single re-circulating flow, or microvortex, that can generate a maximum fluid rotational velocity of up to 12 m s(-1) and a corresponding radial acceleration in excess of 10(6)g. Such microvortices may be exploited in centrifugal microdevices to(More)
Not merely a drop in the ocean: The integration of capillary electrophoresis (CE) with droplet generation driven by electroosmotic flow enabled the compartimentalization of molecular components separated by CE in a series of droplets (see picture; the green bars represent the separated analytes). The droplet-confined bands can be docked and studied on a(More)
As microfluidic systems transition from research tools to disposable clinical-diagnostic devices, new substrate materials are needed to meet both the regulatory requirement as well as the economics of disposable devices. This paper introduces a UV-curable polyurethane-methacrylate (PUMA) substrate that has been qualified for medical use and meets all of the(More)
BACKGROUND Phototherapy is effective for many dermatoses in adults, but there is a paucity of data for its use in children. OBJECTIVES To review the efficacy and tolerability of narrowband UVB phototherapy in children at a tertiary centre in New Zealand, and determine if there were any factors that differentiated responders from non-responders. METHODS(More)
BACKGROUND/OBJECTIVES A virtual lesion clinic (VLC) using store-and-forward teledermoscopy was introduced to reduce waiting times and improve access for skin lesion assessment by dermatologists. We aimed to review the efficiency and patient acceptance of a new community-based teledermoscopy service by comparing it to hospital-based face-to-face (FTF) skin(More)
This paper presents a compact length-dependent saturation current (I dsat) model for deep-submicron MOSFET's based on accurate modeling of the threshold voltage (V th). The proposed unified model has considered all the important two-dimensional (2-D) short-channel effects, such as V th roll-up and roll-off, drain-induced barrier lowering (DIBL),(More)
We recently reported a new UV-curable polyurethane-methacrylate (PUMA) resin that has excellent qualities as a disposable microfluidic substrate for clinical diagnostic applications. This article discusses strategies to improve the production yield of PUMA chips that contain dense and high-aspect-ratio features, which presents unique challenges in demolding(More)