1,706 research outputs found
Automatic Construction of Accurate Image Processing using AdaBoost
Image processing and recognition technologies are required to solve various problems. We have already proposed the system which automatically constructs image processing
with Genetic Programming (GP), Automatic Construction of
Tree-structural Image Transformation (ACTIT). However, it is difficult to construct an accurate image processing for all training image sets if they have various characteristics. In this paper, we propose ACTIT-Boost which automatically constructs an accurate image processing by employing Adaptive Boosting (AdaBoost) to ACTIT. It learns training image sets and their areas which are difficultly approximated to target images in particular. We show experimentally that ACTIT-Boost is more effective in comparison with ordinary ACTIT
An optimal finite-dimensional modeling in heat conduction and diffusion equations with partially known eigenstructure
An optimal finite-dimensional modeling technique is presented for a standard class of distributed parameter systems for heat and diffusion equations. A finite-dimensional nominal model with minimum error bounds in frequency domain is established for spectral systems with partially known eigenvalues and eigenfunctions. The result is derived from a completely characterized geometric figure upon complex plane, of all the frequency responses of the systems that have (i) a finite number of given time constants T/sub i/'s and modal coefficients k/sub i/'s, (ii) an upper bound /spl rho/ to the infinite sum of the absolute values of all the modal coefficients k/sub i/'s, (iii) an upper bound T to the unknown T/sub i/'s, and (iv) a given dc gain G(0). Discussions are made on how each parameter mentioned above makes contribution to bounding error or uncertainty, and we stress that steady state analysis for dc input is used effectively in reduced order modeling and bounding errors. The feasibility of the presented scheme is demonstrated by a simple example of heat conduction in ideal copper rod. </p
Optical trapping and surgery of living yeast cells using a single laser
We present optical trapping and surgery of living yeast cells using two operational modes of a single laser. We used a focused laser beam operating in continuous-wave mode for noninvasive optical trapping and manipulation of single yeast cell. We verified that such operational mode of the laser does not cause any destructive effect on yeast cell wall. By changing the operation of the laser to femtosecond-pulsed mode, we show that a tightly focused beam dissects the yeast cell walls via nonlinear absorption. Lastly, using the combined technique of optical microsurgery and trapping, we demonstrate intracellular organelle extraction and manipulation from a yeast cell. The technique established here will be useful as an efficient method for both surgery and manipulation of living cells using a single laser beam.The project has been funded by the Philippine Council
for Advanced Science and Technology Research and Development
PCASTRD. J. Ando acknowledges the support of
the Japan Student Services Organization JASSO for the
short-term student exchange promotion program
Selection and characterization of promoters based on genomic approach for the molecular breeding of oleaginous fungus Mortierella alpina 1S-4.
To express a foreign gene effectively, a good expression system is required. In this study, we investigated various promoters as useful tools for gene manipulation in oleaginous fungus Mortierella alpina 1S-4. We selected and cloned the promoter regions of 28 genes in M. alpina 1S-4 on the basis of expression sequence tag abundance data. The activity of each promoter was evaluated using the β-glucuronidase (GUS) reporter gene. Eight of these promoters were shown to enhance GUS expression more efficiently than a histone promoter, which is conventionally used for the gene manipulation in M. alpina. Especially, the predicted protein 3 and the predicted protein 6 promoters demonstrated approximately fivefold higher activity than the histone promoter. The activity of some promoters changed along with the cultivation phase of M. alpina 1S-4. Seven promoters with constitutive or time-dependent, high-level expression activity were selected, and deletion analysis was carried out to determine the promoter regions required to retain activity. This is the first report of comprehensive promoter analysis based on a genomic approach for M. alpina. The promoters described here will be useful tools for gene manipulation in this strain
Raman Spectroscopy of magneto-phonon resonances in Graphene and Graphite
The magneto-phonon resonance or MPR occurs in semiconductor materials when
the energy spacing between Landau levels is continuously tuned to cross the
energy of an optical phonon mode. MPRs have been largely explored in bulk
semiconductors, in two-dimensional systems and in quantum dots. Recently there
has been significant interest in the MPR interactions of the Dirac fermion
magnetoexcitons in graphene, and a rich splitting and anti-crossing phenomena
of the even parity E2g long wavelength optical phonon mode have been
theoretically proposed and experimentally observed. The MPR has been found to
crucially depend on disorder in the graphene layer. This is a feature that
creates new venues for the study of interplays between disorder and
interactions in the atomic layers. We review here the fundamentals of MRP in
graphene and the experimental Raman scattering works that have led to the
observation of these phenomena in graphene and graphite
Characterization of galactose-dependent promoters from an oleaginous fungus Mortierella alpina 1S-4.
An inducible promoter is a useful tool for the controlled expression of a given gene. In this report, we describe galactose-dependent promoters for potential use in an oleaginous fungus Mortierella alpina. We cloned the putative promoter regions of two genes encoding galactose metabolic enzymes, GAL1 and GAL10, from the genome of M. alpina 1S-4. The β-glucuronidase (GUS) reporter gene assay in M. alpina 1S-4 revealed that regulation of these promoters was dependent on the presence of galactose in the medium both with and without other sugars. With the GAL10 promoter, an approximately 50-fold increase of GUS activity was demonstrated by addition of galactose into the culture media at any cultivation phase. The 5' deletion analysis of the GAL10 promoter revealed that a promoter region of over 2, 000 bp length was required for its high-level activity and sufficient inducible response. Significantly, this is the first report of inducible promoters of zygomycetes. The GAL10 promoter will be a valuable tool for gene manipulation in M. alpina 1S-4
Conductance fluctuations in the presence of spin scattering
Electron transport through disordered systems that include spin scatterers is
studied numerically. We consider three kinds of magnetic impurities: the Ising,
the XY and the Heisenberg. By extending the transfer matrix method to include
the spin degree of freedom, the two terminal conductance is calculated. The
variance of conductance is halved as the number of spin components of the
magnetic impurities increases. Application of the Zeeman field in the lead
causes a further halving of the variance under certain conditions.Comment: to be published in Phys. Rev.
A search for ferromagnetism in transition-metal-doped piezoelectric ZnO
We present the results of a computational study of ZnO in the presence of Co
and Mn substitutional impurities. The goal of our work is to identify potential
ferromagnetic ground states within the (Zn,Co)O or (Zn,Mn)O material systems
that are also good candidates for piezoelectricity. We find that, in contrast
to previous results, robust ferromagnetism is not obtained by substitution of
Co or Mn on the Zn site, unless additional carriers (holes) are also
incorporated. We propose a practical scheme for achieving such -type doping
in ZnO
Effective healing of endoscopic submucosal dissection-induced ulcers by a single week of proton pump inhibitor treatment: a retrospective study
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