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We present a method for improving the lithographic resolution of digital micromirror devices for flow-lithography using a wobulation technique. While maintaining the area of UV exposure, the lithographic resolution was improved using a wobulation technique, which is a large screen display technique that enhances resolution via overlapping pixels by half a pixel. The edges of a diagonal pattern in a microstructure were smoothly generated with additional sub-patterns compared to conventional single pattern-exposure. In addition, the surface roughness of the microstructure was improved because the gaps between pixels were filled by the overlapping patterns. [ABSTRACT FROM AUTHOR]

In order to match the controllability of traditional pipetting with the advantages of microfluidics, we introduce the concept of polymer based chemical delivery to multichannel capillary patterned cells. Here we demonstrate that UV polymerized hydrogel can be used as a miniature pipet to deliver picolitre chemical quantities to multichannel capillary patterned cells. [ABSTRACT FROM AUTHOR]

We present a simple and high-throughput method for fabricating free-floating hydrogel cell microcarriers using single exposure UV patterning. We also demonstrate magnetic manipulation of the free-floating cell microcarriers using a magnetic nanoparticle-embedded structure for an active agitation and a solution exchange. [ABSTRACT FROM AUTHOR]

Encoded particles have a demonstrated value for multiplexed high-throughput bioassays such as drug discovery and clinical diagnostics. In diverse samples, the ability to use a large number of distinct identification codes on assay particles is important to increase throughput. Proper handling schemes are also needed to readout these codes on free-floating probe microparticles. Here we create vivid, free-floating structural coloured particles with multi-axis rotational control using a colour-tunable magnetic material and a new printing method. Our colour-barcoded magnetic microparticles offer a coding capacity easily into the billions with distinct magnetic handling capabilities including active positioning for code readouts and active stirring for improved reaction kinetics in microscale environments. A DNA hybridization assay is done using the colour-barcoded magnetic microparticles to demonstrate multiplexing capabilities. [ABSTRACT FROM AUTHOR]

Many creatures in nature, such as butterflies and peacocks, display unique brilliant colours, known as ‘structural colours’, which result from the interaction of light with periodic nanostructures on their surfaces. Mimicking such nanostructures found in nature, however, requires state-of-the-art nanofabrication techniques that are slow, expensive and not scalable. Herein, we demonstrate high-resolution patterning of multiple structural colours within seconds, based on successive tuning and fixing of colour using a single material along with a maskless lithography system. We have invented a material called ‘M-Ink’, the colour of which is tunable by magnetically changing the periodicity of the nanostructure and fixable by photochemically immobilizing those structures in a polymer network. We also demonstrate a flexible photonic crystal for the realization of structural colour printing. The simple, controllable and scalable structural colour printing scheme presented may have a significant impact on colour production for general consumer goods. [ABSTRACT FROM AUTHOR]

We demonstrate the microfluidic sorting of directionally oriented (anisotropic) microstructures by their orientational state in solution using the concept of railed microfluidics. After being injected into a microfluidic channel, the microstructures rotate and flip in various directions. In order to sort microstructures in an organized way, we designed the microstructures and the microchannel to allow for orientation-based control of microstructure movement. In order to sort microstructures based on their rotation, we used a wedge shaped fin on the microstructures and a Y-shaped railed microfluidic channel. For sorting flipped particles, we use a double-railed microfluidic channel that has grooves on both its top and bottom surfaces. By integrating the two sorting methods we demonstrated high throughput, autonomous sorting into four different orientational states: unrotated–unflipped, rotated–unflipped, unrotated–flipped, and rotated–flipped. Here we not only demonstrate orientational assembly of directionally dependent microstructures, but also present design considerations for future work. [ABSTRACT FROM AUTHOR]

We introduce a backside island isolation method for silicon-on-insulator (SOI)-based microelectromechanical systems technology and demonstrate vertical comb drive-based two-dimensional gimbaled micromirrors with large static rotation using the isolation method. The proposed isolation method provides electrical isolation and mechanical coupling of SOI structures without additional dielectric backfill and planarization by utilizing timed etched backside handle wafer structures. The backside island is a hidden layer beneath the gimbal and allows independent application of actuation potentials to the gimbal and inner mirror. We developed the fabrication process that accommodates the backside island isolation structures into an established vertical comb drive process, thereby allowing implementation of two-axis gimbaled structures. The maximum static optical deflections of the gimbal and mirror are 46° and 15°, respectively. [ABSTRACT FROM PUBLISHER]

We have investigated the focusing and dynamics of non-spherical polymeric particles in microfluidic flows at finite Reynolds number. The rotational diameter, Dmax, of a particle, regardless of its cross-sectional shape, was found to determine the final focused position, except for the case of asymmetric disks. Additionally, elongated particles with larger Dmax exhibited longer residence times in a horizontal orientation than those with smaller Dmax. These findings inform approaches to hydrodynamically control shaped and barcoded particles for multiplexed biochemical assays. [ABSTRACT FROM AUTHOR]

The article explores the direct two dimensional-to three dimensional transformation of pen drawings. It mentions that pen drawing as a method that allows simple, inexpensive, and intuitive two-dimensional (2D) fabrication. It discusses the freestyle rapid prototyping via pen drawing, as well as mass production of 3D objects via roll-to-roll processing.

Despite the many successes of genome-wide association studies (GWAS), the known susceptibility variants identified by GWAS have modest effect sizes, leading to notable skepticism about the effectiveness of building a risk prediction model from large-scale genetic data. However, in contrast to genetic variants, the family history of diseases has been largely accepted as an important risk factor in clinical diagnosis and risk prediction. Nevertheless, the complicated structures of the family history of diseases have limited their application in clinical practice. Here, we developed a new method that enables incorporation of the general family history of diseases with a liability threshold model, and propose a new analysis strategy for risk prediction with penalized regression analysis that incorporates both large numbers of genetic variants and clinical risk factors. Application of our model to type 2 diabetes in the Korean population (1846 cases and 1846 controls) demonstrated that single-nucleotide polymorphisms accounted for 32.5% of the variation explained by the predicted risk scores in the test data set, and incorporation of family history led to an additional 6.3% improvement in prediction. Our results illustrate that family medical history provides valuable information on the variation of complex diseases and improves prediction performance. [ABSTRACT FROM AUTHOR]