Yoko Yamanishi

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Cell stiffness could be an index for evaluating its activity. Although various systems measuring cell stiffness have been proposed so far, they are slow for adaptively connecting to cell sorters capable of handling more than 1000 [cells/sec]. This paper proposes a new approach that can indirectly evaluate the cell stiffness by measuring the passing time for(More)
This paper presents the high speed microrobot actuation driven by permanent magnets in a microfluidic chip. The riblet surface, which is regularly arrayed V groove reduces the fluid friction and enables stable actuation in high speed. The comprehensive analysis of fluid force, the optimum design and its fabrication were conducted and proved the friction(More)
In this paper we describe a novel fabrication method of three dimensional polymeric magnetically driven microtools (MMT) for non-intrusive and no contamination experiments on a chip. In order to obtain precise and complicated three dimensional patterns of magnetically driven 3D microtools, a grayscale photolithography technique has been applied by making(More)
In this paper we describe novel magnetically driven polymeric microtool for non-intrusive and no contamination experiments on a chip. The composite is formed by suspending magnetite particles (Fe<sub>3</sub>O<sub>4</sub>) in polydimethylsiloxane (PDMS). In order to obtain precise and complicated pattern of micromagnetic tools, a photolithography techniques(More)
Species richness in local communities has been considered an important factor determining the success of invasion by exotic species (the biotic resistance hypothesis). However, the detailed mechanisms, especially the role of predator communities, are not well understood. We studied biotic resistance to an invasive freshwater snail, Pomacea canaliculata, at(More)
In this paper, we introduce an untethered type of magnetically driven microtool (MMT) with a force sensing function to investigate the stimulus characteristics of aquatic microorganisms in a microfluidic chip. The microchip is composed of the proposed MMTs, which have a Si-Ni hybrid structure, a transparent cover made of polydimethylsiloxane (PDMS), a glass(More)
In this paper, on-chip particle loading and dispensing modules are presented with their results for the automation of a single particle retrieving from a microfluidic channel. Our proposed microfluidic chip has several modules. Each one of them has important functions as (a) loading micro-particles singly to main microfluidic flow by the aid of magnetically(More)
We have developed magnetically modified polymeric soft microactuators in microchip as replacement of conventional manual cell manipulations such as pipetting and centrifugation. In the past papers in Yamanishi, Y., et al, (2007) we have reported novel magnetically driven polymeric microtools for non-intrusive and no contamination experiments on a chip. The(More)