Publications by authors named "Kosuke Iwai"

Article Synopsis
  • The study investigates behavioral problems in foster children in Japan using the Eyberg Child Behavior Inventory (ECBI) to collect data from foster and non-foster families.
  • Results indicate that foster children had significantly higher intensity scores for behavioral problems, but there was no notable difference in perceived difficulties between foster and non-foster families.
  • Findings suggest that severe behavioral issues in foster children may be linked to factors like neurological disorders and histories of abuse, while foster parents might adopt a more lenient approach due to these backgrounds.
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We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip. The microfluidic device contains a 10 × 10 element array, and each element contains sets of electrodes for two electric field-actuated operations: electrowetting for merging droplets to mix reagents and electroporation for transformation. This device can perform up to 100 genetic modification reactions in parallel, providing a scalable platform for generating the large number of engineered strains required for the combinatorial optimization of genetic pathways and predictable bioengineering.

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Synthetic biology is an interdisciplinary field that aims to engineer biological systems for useful purposes. Organism engineering often requires the optimization of individual genes and/or entire biological pathways (consisting of multiple genes). Advances in DNA sequencing and synthesis have recently begun to enable the possibility of evaluating thousands of gene variants and hundreds of thousands of gene combinations.

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Real-time detection of basic physiological parameters such as blood pressure and heart rate is an important target in wearable smart devices for healthcare. Among these, the core body temperature is one of the most important basic medical indicators of fever, insomnia, fatigue, metabolic functionality, and depression. However, traditional wearable temperature sensors are based upon the measurement of skin temperature, which can vary dramatically from the true core body temperature.

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Point-of-care (POC) and disposable biomedical applications demand low-power microfluidic systems with pumping components that provide controlled pressure sources. Unfortunately, external pumps have hindered the implementation of such microfluidic systems due to limitations associated with portability and power requirements. Here, we propose and demonstrate a 'finger-powered' integrated pumping system as a modular element to provide pressure head for a variety of advanced microfluidic applications, including finger-powered on-chip microdroplet generation.

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Self-regulating fluidic components are critical to the advancement of microfluidic processors for chemical and biological applications, such as sample preparation on chip, point-of-care molecular diagnostics, and implantable drug delivery devices. Although researchers have developed a wide range of components to enable flow rectification in fluidic systems, engineering microfluidic diodes that function at the low Reynolds number (Re) flows and smaller scales of emerging micro/nanofluidic platforms has remained a considerable challenge. Recently, researchers have demonstrated microfluidic diodes that utilize high numbers of suspended microbeads as dynamic resistive elements; however, using spherical particles to block fluid flow through rectangular microchannels is inherently limited.

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Continuous flow particulate-based microfluidic processors are in critical demand for emerging applications in chemistry and biology, such as point-of-care molecular diagnostics. Challenges remain, however, for accomplishing biochemical assays in which microparticle immobilization is desired or required during intermediate stages of fluidic reaction processes. Here we present a dual-mode microfluidic reactor that functions autonomously under continuous flow conditions to: (i) execute multi-stage particulate-based fluidic mixing routines, and (ii) array select numbers of microparticles during each reaction stage (e.

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This paper describes a simple reusable device that hydrodynamically traps a large number of beads in an array. Guiding pillars allow us to release the trapped beads by simply reversing the flow direction. The trap and reset operations are extremely simple, robust and highly efficient.

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In this study, we have developed a meander-shaped dynamic microfluidic technology that allows us to pair two different types of microbeads in a trapping site. The dynamic microfluidic technology comprises implemented modifications of a conventional dynamic microarray design such as: (i) the combination of a meander-shaped by-pass channel and a trapping channel with a hydrodynamic trapping site and (ii) line-symmetrical formation of the by-pass and trapping channels. Using these modifications, we have successfully trapped different types of sample in one trapping site, and constructed an array of paired beads of different type such as polystyrene beads or hydrogel beads made of agarose, collagen or alginate.

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