Although the G+C content of Thermus aquaticus YT-1 chromosomal DNA is 67.4%, regions with lower G+C content have also been observed. AT-rich DNA-binding proteins may contribute to the thermostability and biological functions of these DNA regions at Thermus growth temperatures. Using double-stranded DNA (dsDNA)-cellulose chromatography, a T.aquaticus YT-1 protein, designated as p25, was identified to bind preferentially to AT-rich DNA. The gene encoding p25 was cloned and sequenced after immunoscreening T.aquaticus YT-1 expression libraries. The deduced primary structure of p25 is 211 amino acids in length with a molecular weight of 23 225 Da. Native p25 was purified and characterized as a homodimer with modification possibly at lysine and arginine residues. Its preferential and temperature-dependent binding to AT-rich DNA was confirmed with mobility-shift DNA-binding assays. The protein was demonstrated to bind preferentially to dsDNA instead of single-stranded DNA. The binding of p25 to dsDNA also improved the thermotolerence of this protein. Overexpression study of fusion p25 suggested that the N-terminus of the protein might form the DNA-binding domain or be closely involved in DNA-binding activity.

Flow-focusing is used in microfluidics to generate droplets that are smaller than the characteristic length scale of the flow geometry. Conventionally, flow-focusing takes place inside micrometer-sized channels due to capillary effects. In this study, we demonstrate that the transient meniscus profile created with Faraday waves on liquid films can enable flow-focusing. Using a magnetic shaker, we generate Faraday waves on a liquid film leading to flow-focusing which increases the resolution of a nozzle-less, jet-based printing technique called blister-actuated laser-induced forward transfer (BA-LIFT). We perform experiments to demonstrate how transient meniscus formation enables jetting at lower laser pulse energies than the threshold, and use numerical modeling to examine this process at smaller length scales relevant to printing applications.

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Abstract. Demands for small-scale and low-cost robots have witnessed a great increase in recent years [1][2][3][4][5]. This paper introduces the design and fabrication of a novel, simple, low-cost and designer-friendly locomotive robot. The materials and tools to build the robot originate from everyday life. The robot is pneumatically powered and manually controlled by simply pumping and vacuuming the syringe repeatedly, which realizes reliable locomotion by folding and opening of the planes. In order to realize this complicated motion, a "3D Sticky Actuator" is developed. The motion and force analysis of actuator are then modelled by the numerical method to develop the relations between design parameters. This suggests a systematic and user interactive way of manufacturing various shapes of the actuator, depending on user-defined road condition (e.g. obstacles and slopes) and other constraints. One key advantage of the paper-based robot is suggested by its high feasibility.

Fast and versatile alteration of focal positions is critical for applications including selective volumetric modification and parallel laser processing. In this Letter, we implement and characterize an ultrafast, variable focal system using a tunable acoustic gradient of index lens to achieve multi-focal laser processing. We apply our method to the femtosecond laser-induced intra-volumetric modification in glass to show the flexibility in controlling focal positions. Based on this understanding, we exploit the multi-focal nature of the system to demonstrate laser machining on both surfaces of a transparent glass slide in a single lateral scan.