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Detection of anomalous cells such as cancer cells from normal blood cells has the potential to contribute greatly to cancer diagnosis and therapy. Conventional methods for the detection of cancer cells are usually tedious and cumbersome. Herein, we report on the use of a particle size analyzer for the convenient size-based differentiation of cancer cells from normal cells. Measurements made using a particle size analyzer revealed that size parameters for cancer cells are significantly greater (e.g., inner diameter and width) than the corresponding values for normal cells (white blood cells (WBC), lymphocytes and splenocytes), with no significant difference in shape parameters (e.g., circularity and convexity). The inner diameter of many cancer cell lines is greater than 10 µm, in contrast to normal cells. For the detection of WBC having similar size to that of cancer cells, we developed a PC software "Cancer Cell Finder" that differentiates them from cancer cells based on brightness stationary points on a cell surface. Furthermore, the aforementioned method was validated for cancer cell/clusters detection in spiked mouse blood samples (a B16 melanoma mouse xenograft model) and circulating tumor cell cluster-like particles in the cat and dog (diagnosed with cancer) blood samples. These results provide insights into the possible applicability of the use of a particle size analyzer in conjunction with PC software for the convenient detection of cancer cells in experimental and clinical samples for theranostics.

The present paper describes a closed-form transfer function of low-delay band-pass maximally flat FIR digital differentiators. Band-pass maximally flat FIR digital differentiators provide extremely high-accuracy differentiation around the center frequency which is adjusted arbitrarily. At the same time, they can reduce noise in the frequency except around the center frequency. However, the conventional method for designing band-pass maximally flat FIR digital differentiators requires linear phase characteristics. In contrast, the proposed method can realize low-delay characteristics as well as linear phase characteristics and, therefore, is a general expression of band-pass maximally flat FIR digital differentiators. The proposed transfer function is achieved as the sum of two maximally flat complex FIR digital differentiators, the coefficients of which are complex conjugates of each other. The transfer functions of these complex differentiators are derived as closed-form solutions, so that the proposed transfer function is also described as a closed-form solution. Through design examples, the effectiveness of the proposed method is confirmed.

2-D maximally flat diamond-shaped half-band linear phase FIR digital filters are used in sampling structure conversion. In some cases, this filter is expected to have different filter order for each dimension. However, the conventional methods can realize such filters only if difference between each order is 2, 4 and 6. In this paper, we proposed a closed-form transfer function of 2-D low-pass maximally flat diamond-shaped half-band FIR digital filters with arbitrary filter orders. The constraints to treat arbitrary filter orders are firstly proposed. Then, a closed-form transfer function is achieved by using Bernstein polynomial.

Objective. The aim of this study was to evaluate the usefulness of reconstructed computed tomography (CT) images using OsiriX software in detecting wooden and bamboo foreign bodies. Methods. Four sizes of wet and dry wooden and bamboo foreign bodies were selected to be analyzed. Those in the air and in the head of edible swine were scanned with a multidetector row CT scanner. The images were evaluated with OsiriX software in the bone and the abdomen window setting as unprocessed images. Three-dimensional rendered images assigned colors and opacity by a 16-bit color look-up table (CLUT) editor in OsiriX software were evaluated as processed images. Results. In the unprocessed images, dry and wet foreign bodies in the air were not detected except a part of wet wooden foreign bodies, and all the dry and wet foreign bodies in the swine’s head mimicked air with linear shapes. In the processed images, all the dry and wet foreign bodies in the air were detected clearly, and all the wooden and some of the bamboo foreign bodies in the swine’s head were detected clearly. Conclusions. CT images processed using OsiriX software, especially with a CLUT editor, were useful in detecting wooden and bamboo foreign bodies.

This paper presents a quadratic kernel with four variable parameters for image enlargement. The proposed kernel can generate peak and valley information of the signals by considering the characteristics of the image and by changing these parameters. Moreover, as the proposed kernel is the extension of the linear interpolation and the nearest-neighbor interpolation, the forms of the proposed kernel are also used selectively depending on the characteristics of signal points which are used for parameter estimation. The various standard images are enlarged using the proposed kernel, and the performance of the proposed kernel is evaluated with MSE of the enlarged images. It has been shown that the performance of the proposed kernel is better than the other methods, such as the cubic interpolations that are often used in image processing.

Variable digital filters are useful for various signal processing and communication applications where the frequency characteristics, such as fractional delays and cutoff frequencies, can be varied. In this paper, we propose a design method of variable FIR digital filters with an approximate linear phase characteristic in the passband. The proposed variable FIR filters have some large attenuation in stopband and their large attenuation can be varied by spectrum parameters. In the proposed design method, a quasi-equiripple characteristic can be obtained by using an iterative weighted least square method. The usefulness of the proposed design method is verified through some examples., {"references":["C. K. S. Pun, S. C. Chan, K. S. Yeung, and K. L. Ho, \"On the design\nand implementation of FIR and IIR digital filters with variable frequency\ncharactericstics,\" IEEE Trans. Circuits Syst. II, Analog Digit. Signal\nProcess., vol. 49, no. 11, pp. 689.703, Nov. 2002.","L. R. Rabiner and B. GoldÔÇó ÔÇó\"Theory and application of digital signal\nprocessing,\" Prentice-HallÔÇó ÔÇóNew JerseyÔÇó ÔÇó1975.","T. Shinbo, Y. Sugita, N. Aikawa, T. Kimura, Y. Wakasa, and T. Morichi,\n\"Design Method of FIR Filters with Variable Piecewise Stopband,\"\nIEICE Trans. Fundamentals (Japanese Edition), Vol. J87-A, No. 12,\npp.1511-1517, Dec. 2007.","S. Takahashi, N. Aikawa, Y. Wakasa, and M. Nakatani, \"FIR Filters with\nVariable Stopbands,\" IEICE Trans. Fundamentals (Japanese Edition),\nVol. J90-A, No. 10, pp.767-770, Oct. 2007.","T. Takahashi, T. Miyata, and N. Aikawa, \"An Iterative WLS Chebyshev\nApproximation method for the Design of FIR Digital Filters with\nVariable Stopbands,\" IEICE DSP Symposium, B3-1, Nov. 2008.","J. -C. Liu and S. -J. You, \"Weighted Least Squares Near-equiripple\nApproximation of Variable Fractional Delay FIR Filters,\" IET Signal\nProcessing, Vol. 1, no. 2, June 2007.","T. B. Deng, \"An improved method for designing variavle recursive\ndigital filters with guaranteed stability,\" Signal Processing, vol. 81, pp.\n439-446, 2001.","W. R. Lee, L. Caccetta, and V. Rehbock, \"Optimal Design of All-Pass\nVariable Fractional-Delay Digital Filters,\" IEEE Transaction on Circuits\nand Syatems-I: Regular Papers, Vol. 55, no. 5, June 2008.","L. J. Karam and J. H. McClellan, Complex approximation for FIR filter\ndesign, IEEE Trans. Circuits and Systems, vol. CAS-42, no.3, pp.207-\n244, April 1995.\n[10] W.-S. Lu, Minimax design of nonlinear-phase FIR filters: A least-pth\napproach, Proc. of 2002 IEEE International Symposium on Circuits and\nSystems, vol. 1, pp. 409-412, May 2002.\n[11] Yong Ching LimÔÇó ÔÇóJu-Hong LeeÔÇó ÔÇóC.K. Chen, and Rong-Huan YangÔÇó ÔÇó\"A\nWeighted Least Squares Algorithm for Quasi-Equiripple FIR and IIR\nDigital Filter Design,\" IEEE Trans. Signal Processing, Vol.40, No. 3,\npp.551-558, Mar., 1992.\n[12] S. -C. Pei and J. -J. Shyu, \"Design of Arbitrary Complex Coefficient FIR\nDigital Filters by Complex Weighted Least Squares Approximation,\"\nIEEE Trans. on Circuits and Systems-II: Analog and Digital Signal\nProcessing, vol. 41, no. 12, pp. 817-820, Dec. 1994.\n[13] T. B. Deng, \"Weighted least-squares method for designing arbitrarily\n1-D FIR digital filters,\" Signal Processing, vol. 80, pp. 597-613, 2000.\n[14] C. Sidney, J. A. Barreto, and I. W. Selesnick, \"Iterative Reweighted\nLeast-Squares Design of FIR Filters,\" IEEE Trans. on Signal Processing,\nvol. 42, no. 11, pp. 2926-2936, Nov. 1994.\n[15] A. S. Rukhlenko, \"Iterative WLS Design of SAW Bandpass Filters,\"\nIEEE Trans. on Ultrasonics, Ferroelectrics, and Frequency Control, vol.\n54, no. 10, pp. 1930-1935, Oct. 2007."]}

We have investigated the microstructure and the coercivity of Nd10Fe77.5B12.5−xMx (M=Zr, Nb, x=0~3) bulk nanocomposite magnets in order to obtain insight into the factors responsible for the coercivity increase by the addition of Zr and Nb. The volume fraction of the Nd2Fe14B phase is found to increase appreciably with the Zr and Nb addition, indicating that the Zr/Nb addition is effective in the suppression of a second phase. The increase of the coercivity in both alloys is understood to be due to the increase of the volume fraction of the Nd2Fe14B hard phase.