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Hitoshi Kanamori - One of the best experts on this subject based on the ideXlab platform.

  • Proportionality between Wiener spectra of quantum Mottle and the squares of modulation transfer functions.
    Physics in medicine and biology, 1999
    Co-Authors: Hidetaka Arimura, Masao Matsumoto, Hideaki Kubota, Hitoshi Kanamori
    Abstract:

    Rossmann proposed that the Wiener spectra of the quantum Mottle of radiographs made using screen-film systems were proportional to the squares of the modulation transfer functions (MTFs) of the screen-film systems. On the other hand, Lubberts theoretically pointed out that the shape of the Wiener spectrum of the quantum Mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e. the square of the MTF of the screen-film systems. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectra of the quantum Mottle and the squares of the MTFs of screen-film systems using two screen-film systems having different screen thicknesses. For this purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum Mottle at each spatial frequency when the Wiener spectral values of the screen Mottle were separated into those of the quantum Mottle and structure Mottle. The correction factor is the ratio of the normalized Wiener spectrum of the quantum Mottle to the square of the MTF of the screen-film system. As a result, for a thin screen, the correction factors were unity for all spatial frequencies; on the contrary, for a thick screen, the factor increased with spatial frequency. By calculating the theoretical correction factors using the models for the MTF and Wiener spectrum of the quantum Mottle of Nishikawa and Yaffe based on Lubberts' theory, we verified that our experimental results agreed with Lubberts' theory. Furthermore, by obtaining the screen thickness dependence of the theoretical correction factors for the two screens, we showed that, for screens thinner than 0.02 mm, Rossmann's theory can be applied to the relationship between the Wiener spectrum of the quantum Mottle and the MTF of the screen-film system, whereas for screens thicker than 0.02 mm, Lubberts' theory should be applied.

  • Relation between radiographic Mottle for double and single emulsions
    Medical physics, 1998
    Co-Authors: Hidetaka Arimura, T. Ikari, M. Okamoto, N. Nakamori, Atsushi Takigawa, Masao Matsumoto, Hideaki Kubota, Tomohiko Okawa, Hitoshi Kanamori
    Abstract:

    The radiographic density fluctuations produced by using dual screen-film systems are designated as the radiographic Mottle. The density fluctuation of the radiographic Mottle for the double emulsions at a density of the double emulsions consists of those for the front and back emulsions on a radiograph. However, the relation between the Wiener spectra of the radiographic Mottle for the double and single emulsions had not been studied. Hence we compared the Wiener spectra of the radiographic Mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs and with the sum of those for the emulsions at the same densities. At all densities of more than 0.62 for lower spatial frequencies (< or = 1 mm-1), the Wiener spectral values of the radiographic Mottle for the double emulsions were greater than the sum of those for the front and back emulsions for both comparisons on the same radiographs and at the same densities. In order to investigate the reason of the above phenomena, we separated the Wiener spectral values of the radiographic Mottle for various densities into those of the three factors, i.e., quantum Mottle, structure Mottle, and film granularity, and performed the same comparisons as the radiographic Mottle. Also, to explain the results for the three factors, we obtained the Wiener spectral values of the spatial fluctuations of the light exposure or the fluorescence intensity and the gradients of the characteristic curves of the film for the double and single emulsions of the x-ray film. As a result of the investigation, we found that the phenomena on the radiographic Mottle were caused by that (1) on the same radiographs the squares of the gradients of the characteristic curves for the double emulsions were about 5.3 times as great as those for the single emulsion at densities of more than 0.62 of the double emulsions, and (2) at the same density of more than 0.62 those were more than about 2.2 times as great as those for the single emulsion.

  • Comparison of Wiener spectra of quantum Mottle for screen-film systems with modulation transfer functions
    Medical Imaging 1998: Physics of Medical Imaging, 1998
    Co-Authors: Hidetaka Arimura, Masao Matsumoto, Hideaki Kubota, Tomohiko Okawa, Hitoshi Kanamori
    Abstract:

    Rossmann proposed that the Wiener spectrum of the quantum Mottle was proportional to the square of the modulation transfer function (MTF) of the screen-film system. On the other hand, Lubberts pointed out that the shape of the Wiener spectrum of the quantum Mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e., the square of the MTF of the screen-film system. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectrum of the quantum Mottle and the square of the MTF of the screen-film system using two screen-film systems having different screen thicknesses. For the purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum Mottle, that is, the ratios of the sums of the squares of the MTFs for different depths to the squares of the MTFs of the screen-film systems so that the theoretical Wiener spectral values of the screen Mottle fitted the experimental values. For the thin screen, the correction factors were unity for all spatial frequencies, that is, the Wiener spectra of the quantum Mottle were proportional to the square of the MTF of the screen-film system. On the contrary, for the thick screen, the factor increased with the spatial frequency, that is, the Wiener spectra were proportional to the sum of the squares of the MTFs. Therefore, we can conclude that the relation between the Wiener spectrum of the quantum Mottle and the MTF of the screen-film system, for thin screen, agrees with Rossmann's theory, whereas, for thick screen, agrees with Lubberts' theory.

  • X-ray tube voltage dependence of three factors of radiographic Mottle for single and double emulsions
    Medical Imaging 1996: Physics of Medical Imaging, 1996
    Co-Authors: Hidetaka Arimura, T. Ikari, M. Okamoto, N. Nakamori, Atsushi Takigawa, Masao Matsumoto, Hideaki Kubota, Hitoshi Kanamori
    Abstract:

    We have obtained the density or x-ray tube voltage dependence of the Wiener spectra of the three factors of radiographic Mottle, i.e., quantum Mottle, structure Mottle, and film granularity, for the double emulsions of the x-ray film. For the purpose, we proposed a method for obtaining the Wiener spectrum of each of the three factors for the double emulsions. To investigate the relation between the Wiener spectra of the quantum Mottle for the double and single emulsions, we compared the Wiener spectra of the quantum Mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs. The Wiener spectral values of the quantum Mottle for the double emulsions at 0 mm-1 were greater than the sums of the Wiener spectral values of the quantum Mottle for the front and back emulsions at tube voltages of 50 to 100 kV. We found that this was the result which originated from the following phenomena: (1) the noise-equivalent numbers of quanta (NEQ) of the dual screens were roughly equal to the sum of the NEQ of the front and back screens; (2) the squares of the gradients for the double emulsions were more than four times on an average as great as those for the front and back emulsions.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

  • Influence of the Crossover Effect on X-Ray Tube Voltage Dependence of Quantum Mottle
    The Journal of Photographic Science, 1996
    Co-Authors: Hidetaka Arimura, M. Okamoto, N. Nakamori, Masao Matsumoto, Hideaki Kubota, T. Okatoa, T. Lkari, A. Takigatoa, Hitoshi Kanamori
    Abstract:

    AbstractThe influence of the crossover effect on the tube voltage dependence of the quantum Mottle for the front and back emulsion has been investigated. A new method is proposed for separating the Wiener spectra of the screen Mottle for the front and back emulsions with the crossover effect into those of the quantum Mottle and the structure Mottle and a method for obtaining the detective quantum efficiency (DQE) and the noise-equivalent number of quanta (NEQ).The numbers of incident X-ray photons with the crossover effect were smaller than those without the effect for all tube voltages studied. However, at tube voltages below about 75 or 80 kV, the Wiener spectral values of the quantum Mottle with the crossover effect at 0 mm 1 were smaller than those without the effect. The Wiener spectral value increased with the tube voltage and, at tube voltages above about 75 or 80 kV, exceeded that without the effect. Because the Wiener spectrum of the quantum Mottle is proportional to the reciprocal of the NEQ, th...

Hidetaka Arimura - One of the best experts on this subject based on the ideXlab platform.

  • Proportionality between Wiener spectra of quantum Mottle and the squares of modulation transfer functions.
    Physics in medicine and biology, 1999
    Co-Authors: Hidetaka Arimura, Masao Matsumoto, Hideaki Kubota, Hitoshi Kanamori
    Abstract:

    Rossmann proposed that the Wiener spectra of the quantum Mottle of radiographs made using screen-film systems were proportional to the squares of the modulation transfer functions (MTFs) of the screen-film systems. On the other hand, Lubberts theoretically pointed out that the shape of the Wiener spectrum of the quantum Mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e. the square of the MTF of the screen-film systems. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectra of the quantum Mottle and the squares of the MTFs of screen-film systems using two screen-film systems having different screen thicknesses. For this purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum Mottle at each spatial frequency when the Wiener spectral values of the screen Mottle were separated into those of the quantum Mottle and structure Mottle. The correction factor is the ratio of the normalized Wiener spectrum of the quantum Mottle to the square of the MTF of the screen-film system. As a result, for a thin screen, the correction factors were unity for all spatial frequencies; on the contrary, for a thick screen, the factor increased with spatial frequency. By calculating the theoretical correction factors using the models for the MTF and Wiener spectrum of the quantum Mottle of Nishikawa and Yaffe based on Lubberts' theory, we verified that our experimental results agreed with Lubberts' theory. Furthermore, by obtaining the screen thickness dependence of the theoretical correction factors for the two screens, we showed that, for screens thinner than 0.02 mm, Rossmann's theory can be applied to the relationship between the Wiener spectrum of the quantum Mottle and the MTF of the screen-film system, whereas for screens thicker than 0.02 mm, Lubberts' theory should be applied.

  • Relation between radiographic Mottle for double and single emulsions
    Medical physics, 1998
    Co-Authors: Hidetaka Arimura, T. Ikari, M. Okamoto, N. Nakamori, Atsushi Takigawa, Masao Matsumoto, Hideaki Kubota, Tomohiko Okawa, Hitoshi Kanamori
    Abstract:

    The radiographic density fluctuations produced by using dual screen-film systems are designated as the radiographic Mottle. The density fluctuation of the radiographic Mottle for the double emulsions at a density of the double emulsions consists of those for the front and back emulsions on a radiograph. However, the relation between the Wiener spectra of the radiographic Mottle for the double and single emulsions had not been studied. Hence we compared the Wiener spectra of the radiographic Mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs and with the sum of those for the emulsions at the same densities. At all densities of more than 0.62 for lower spatial frequencies (< or = 1 mm-1), the Wiener spectral values of the radiographic Mottle for the double emulsions were greater than the sum of those for the front and back emulsions for both comparisons on the same radiographs and at the same densities. In order to investigate the reason of the above phenomena, we separated the Wiener spectral values of the radiographic Mottle for various densities into those of the three factors, i.e., quantum Mottle, structure Mottle, and film granularity, and performed the same comparisons as the radiographic Mottle. Also, to explain the results for the three factors, we obtained the Wiener spectral values of the spatial fluctuations of the light exposure or the fluorescence intensity and the gradients of the characteristic curves of the film for the double and single emulsions of the x-ray film. As a result of the investigation, we found that the phenomena on the radiographic Mottle were caused by that (1) on the same radiographs the squares of the gradients of the characteristic curves for the double emulsions were about 5.3 times as great as those for the single emulsion at densities of more than 0.62 of the double emulsions, and (2) at the same density of more than 0.62 those were more than about 2.2 times as great as those for the single emulsion.

  • Comparison of Wiener spectra of quantum Mottle for screen-film systems with modulation transfer functions
    Medical Imaging 1998: Physics of Medical Imaging, 1998
    Co-Authors: Hidetaka Arimura, Masao Matsumoto, Hideaki Kubota, Tomohiko Okawa, Hitoshi Kanamori
    Abstract:

    Rossmann proposed that the Wiener spectrum of the quantum Mottle was proportional to the square of the modulation transfer function (MTF) of the screen-film system. On the other hand, Lubberts pointed out that the shape of the Wiener spectrum of the quantum Mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e., the square of the MTF of the screen-film system. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectrum of the quantum Mottle and the square of the MTF of the screen-film system using two screen-film systems having different screen thicknesses. For the purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum Mottle, that is, the ratios of the sums of the squares of the MTFs for different depths to the squares of the MTFs of the screen-film systems so that the theoretical Wiener spectral values of the screen Mottle fitted the experimental values. For the thin screen, the correction factors were unity for all spatial frequencies, that is, the Wiener spectra of the quantum Mottle were proportional to the square of the MTF of the screen-film system. On the contrary, for the thick screen, the factor increased with the spatial frequency, that is, the Wiener spectra were proportional to the sum of the squares of the MTFs. Therefore, we can conclude that the relation between the Wiener spectrum of the quantum Mottle and the MTF of the screen-film system, for thin screen, agrees with Rossmann's theory, whereas, for thick screen, agrees with Lubberts' theory.

  • X-ray tube voltage dependence of three factors of radiographic Mottle for single and double emulsions
    Medical Imaging 1996: Physics of Medical Imaging, 1996
    Co-Authors: Hidetaka Arimura, T. Ikari, M. Okamoto, N. Nakamori, Atsushi Takigawa, Masao Matsumoto, Hideaki Kubota, Hitoshi Kanamori
    Abstract:

    We have obtained the density or x-ray tube voltage dependence of the Wiener spectra of the three factors of radiographic Mottle, i.e., quantum Mottle, structure Mottle, and film granularity, for the double emulsions of the x-ray film. For the purpose, we proposed a method for obtaining the Wiener spectrum of each of the three factors for the double emulsions. To investigate the relation between the Wiener spectra of the quantum Mottle for the double and single emulsions, we compared the Wiener spectra of the quantum Mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs. The Wiener spectral values of the quantum Mottle for the double emulsions at 0 mm-1 were greater than the sums of the Wiener spectral values of the quantum Mottle for the front and back emulsions at tube voltages of 50 to 100 kV. We found that this was the result which originated from the following phenomena: (1) the noise-equivalent numbers of quanta (NEQ) of the dual screens were roughly equal to the sum of the NEQ of the front and back screens; (2) the squares of the gradients for the double emulsions were more than four times on an average as great as those for the front and back emulsions.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

  • Influence of the Crossover Effect on X-Ray Tube Voltage Dependence of Quantum Mottle
    The Journal of Photographic Science, 1996
    Co-Authors: Hidetaka Arimura, M. Okamoto, N. Nakamori, Masao Matsumoto, Hideaki Kubota, T. Okatoa, T. Lkari, A. Takigatoa, Hitoshi Kanamori
    Abstract:

    AbstractThe influence of the crossover effect on the tube voltage dependence of the quantum Mottle for the front and back emulsion has been investigated. A new method is proposed for separating the Wiener spectra of the screen Mottle for the front and back emulsions with the crossover effect into those of the quantum Mottle and the structure Mottle and a method for obtaining the detective quantum efficiency (DQE) and the noise-equivalent number of quanta (NEQ).The numbers of incident X-ray photons with the crossover effect were smaller than those without the effect for all tube voltages studied. However, at tube voltages below about 75 or 80 kV, the Wiener spectral values of the quantum Mottle with the crossover effect at 0 mm 1 were smaller than those without the effect. The Wiener spectral value increased with the tube voltage and, at tube voltages above about 75 or 80 kV, exceeded that without the effect. Because the Wiener spectrum of the quantum Mottle is proportional to the reciprocal of the NEQ, th...

E W Kitajima - One of the best experts on this subject based on the ideXlab platform.

  • Brugmansia suaveolens Mottle virus, a novel potyvirus causing leaf mottling of Brugmansia suaveolens in Brazil.
    Archives of Virology, 2008
    Co-Authors: Natalia Lucinda, Renato B. Salaroli, Tatsuya Nagata, Alice Kazuko Inoue-nagata, E W Kitajima
    Abstract:

    A potyvirus was isolated from Brugmansia suaveolens showing leaf mottling and tentatively named Brugmansia suaveolens Mottle virus (BsMoV). The virus (isolate Bs-Campinas) could infect some solanaceous plants and two Chenopodium species, and was transmitted by aphids. Symptomatic leaves contained flexuous particles and cylindrical inclusions. RT-PCR amplification using potyvirus universal primers produced a DNA fragment of 1851 nt (3′ terminal genomic region), which shared 71% nucleotide identity with Pepper Mottle virus, the best-matched potyvirus sequence. Since this identity value is below the threshold currently used to discriminate Potyvirus species, Brugmansia suaveolens Mottle virus most likely represents a new Potyvirus species.

Masao Matsumoto - One of the best experts on this subject based on the ideXlab platform.

  • Proportionality between Wiener spectra of quantum Mottle and the squares of modulation transfer functions.
    Physics in medicine and biology, 1999
    Co-Authors: Hidetaka Arimura, Masao Matsumoto, Hideaki Kubota, Hitoshi Kanamori
    Abstract:

    Rossmann proposed that the Wiener spectra of the quantum Mottle of radiographs made using screen-film systems were proportional to the squares of the modulation transfer functions (MTFs) of the screen-film systems. On the other hand, Lubberts theoretically pointed out that the shape of the Wiener spectrum of the quantum Mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e. the square of the MTF of the screen-film systems. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectra of the quantum Mottle and the squares of the MTFs of screen-film systems using two screen-film systems having different screen thicknesses. For this purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum Mottle at each spatial frequency when the Wiener spectral values of the screen Mottle were separated into those of the quantum Mottle and structure Mottle. The correction factor is the ratio of the normalized Wiener spectrum of the quantum Mottle to the square of the MTF of the screen-film system. As a result, for a thin screen, the correction factors were unity for all spatial frequencies; on the contrary, for a thick screen, the factor increased with spatial frequency. By calculating the theoretical correction factors using the models for the MTF and Wiener spectrum of the quantum Mottle of Nishikawa and Yaffe based on Lubberts' theory, we verified that our experimental results agreed with Lubberts' theory. Furthermore, by obtaining the screen thickness dependence of the theoretical correction factors for the two screens, we showed that, for screens thinner than 0.02 mm, Rossmann's theory can be applied to the relationship between the Wiener spectrum of the quantum Mottle and the MTF of the screen-film system, whereas for screens thicker than 0.02 mm, Lubberts' theory should be applied.

  • Relation between radiographic Mottle for double and single emulsions
    Medical physics, 1998
    Co-Authors: Hidetaka Arimura, T. Ikari, M. Okamoto, N. Nakamori, Atsushi Takigawa, Masao Matsumoto, Hideaki Kubota, Tomohiko Okawa, Hitoshi Kanamori
    Abstract:

    The radiographic density fluctuations produced by using dual screen-film systems are designated as the radiographic Mottle. The density fluctuation of the radiographic Mottle for the double emulsions at a density of the double emulsions consists of those for the front and back emulsions on a radiograph. However, the relation between the Wiener spectra of the radiographic Mottle for the double and single emulsions had not been studied. Hence we compared the Wiener spectra of the radiographic Mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs and with the sum of those for the emulsions at the same densities. At all densities of more than 0.62 for lower spatial frequencies (< or = 1 mm-1), the Wiener spectral values of the radiographic Mottle for the double emulsions were greater than the sum of those for the front and back emulsions for both comparisons on the same radiographs and at the same densities. In order to investigate the reason of the above phenomena, we separated the Wiener spectral values of the radiographic Mottle for various densities into those of the three factors, i.e., quantum Mottle, structure Mottle, and film granularity, and performed the same comparisons as the radiographic Mottle. Also, to explain the results for the three factors, we obtained the Wiener spectral values of the spatial fluctuations of the light exposure or the fluorescence intensity and the gradients of the characteristic curves of the film for the double and single emulsions of the x-ray film. As a result of the investigation, we found that the phenomena on the radiographic Mottle were caused by that (1) on the same radiographs the squares of the gradients of the characteristic curves for the double emulsions were about 5.3 times as great as those for the single emulsion at densities of more than 0.62 of the double emulsions, and (2) at the same density of more than 0.62 those were more than about 2.2 times as great as those for the single emulsion.

  • Comparison of Wiener spectra of quantum Mottle for screen-film systems with modulation transfer functions
    Medical Imaging 1998: Physics of Medical Imaging, 1998
    Co-Authors: Hidetaka Arimura, Masao Matsumoto, Hideaki Kubota, Tomohiko Okawa, Hitoshi Kanamori
    Abstract:

    Rossmann proposed that the Wiener spectrum of the quantum Mottle was proportional to the square of the modulation transfer function (MTF) of the screen-film system. On the other hand, Lubberts pointed out that the shape of the Wiener spectrum of the quantum Mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e., the square of the MTF of the screen-film system. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectrum of the quantum Mottle and the square of the MTF of the screen-film system using two screen-film systems having different screen thicknesses. For the purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum Mottle, that is, the ratios of the sums of the squares of the MTFs for different depths to the squares of the MTFs of the screen-film systems so that the theoretical Wiener spectral values of the screen Mottle fitted the experimental values. For the thin screen, the correction factors were unity for all spatial frequencies, that is, the Wiener spectra of the quantum Mottle were proportional to the square of the MTF of the screen-film system. On the contrary, for the thick screen, the factor increased with the spatial frequency, that is, the Wiener spectra were proportional to the sum of the squares of the MTFs. Therefore, we can conclude that the relation between the Wiener spectrum of the quantum Mottle and the MTF of the screen-film system, for thin screen, agrees with Rossmann's theory, whereas, for thick screen, agrees with Lubberts' theory.

  • X-ray tube voltage dependence of three factors of radiographic Mottle for single and double emulsions
    Medical Imaging 1996: Physics of Medical Imaging, 1996
    Co-Authors: Hidetaka Arimura, T. Ikari, M. Okamoto, N. Nakamori, Atsushi Takigawa, Masao Matsumoto, Hideaki Kubota, Hitoshi Kanamori
    Abstract:

    We have obtained the density or x-ray tube voltage dependence of the Wiener spectra of the three factors of radiographic Mottle, i.e., quantum Mottle, structure Mottle, and film granularity, for the double emulsions of the x-ray film. For the purpose, we proposed a method for obtaining the Wiener spectrum of each of the three factors for the double emulsions. To investigate the relation between the Wiener spectra of the quantum Mottle for the double and single emulsions, we compared the Wiener spectra of the quantum Mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs. The Wiener spectral values of the quantum Mottle for the double emulsions at 0 mm-1 were greater than the sums of the Wiener spectral values of the quantum Mottle for the front and back emulsions at tube voltages of 50 to 100 kV. We found that this was the result which originated from the following phenomena: (1) the noise-equivalent numbers of quanta (NEQ) of the dual screens were roughly equal to the sum of the NEQ of the front and back screens; (2) the squares of the gradients for the double emulsions were more than four times on an average as great as those for the front and back emulsions.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

  • Influence of the Crossover Effect on X-Ray Tube Voltage Dependence of Quantum Mottle
    The Journal of Photographic Science, 1996
    Co-Authors: Hidetaka Arimura, M. Okamoto, N. Nakamori, Masao Matsumoto, Hideaki Kubota, T. Okatoa, T. Lkari, A. Takigatoa, Hitoshi Kanamori
    Abstract:

    AbstractThe influence of the crossover effect on the tube voltage dependence of the quantum Mottle for the front and back emulsion has been investigated. A new method is proposed for separating the Wiener spectra of the screen Mottle for the front and back emulsions with the crossover effect into those of the quantum Mottle and the structure Mottle and a method for obtaining the detective quantum efficiency (DQE) and the noise-equivalent number of quanta (NEQ).The numbers of incident X-ray photons with the crossover effect were smaller than those without the effect for all tube voltages studied. However, at tube voltages below about 75 or 80 kV, the Wiener spectral values of the quantum Mottle with the crossover effect at 0 mm 1 were smaller than those without the effect. The Wiener spectral value increased with the tube voltage and, at tube voltages above about 75 or 80 kV, exceeded that without the effect. Because the Wiener spectrum of the quantum Mottle is proportional to the reciprocal of the NEQ, th...

Wilhelm Jelkmann - One of the best experts on this subject based on the ideXlab platform.

  • Development of PCR primer pairs for the characterization and detection of several related filamentous viruses of cherry
    Acta Horticulturae, 2001
    Co-Authors: M.e. Rott, Wilhelm Jelkmann
    Abstract:

    Cherry can be infected by a number of mottling diseases caused by either filamentous viruses or suspected of being caused by filamentous viruses. The causal agents for two of these diseases have been previously described, Cherry green ring Mottle virus (CGRMV) a tentative member of the foveaviruses, and Cherry Mottle leaf virus (CMLV) a member of the trichoviruses. In a separate article we also present the complete nucleotide sequence of Cherry necrotic rusty Mottle virus (CNRMV). For the mottling diseases, cherry rusty Mottle (CRM) and cherry necrotic mottling (CNM), data is presented identifying viruses associated with each disease. Viruses associated with European isolates of cherry Mottle leaf (CML) CRM, CNRM and CNM all appear to be closely related to CGRMV and can be tentatively included in the foveavirus genus. An additional, related virus, was discovered during the course of these studies and would appear to be a fairly common latent virus of cherry. It is currently unclear whether this virus is associated with cherry mottling disease (CMot), or is a previously undescribed virus. Several RT-PCR primers are presented for the detection of the different viruses.

  • Characterization and Detection of Several Filamentous Viruses of Cherry: Adaptation of an Alternative Cloning Method (DOP-PCR), and Modification of an RNA Extraction Protocol
    European Journal of Plant Pathology, 2001
    Co-Authors: M.e. Rott, Wilhelm Jelkmann
    Abstract:

    For the identification and analysis of new RNA plant viruses infecting fruit trees, an initial step often involves the laborious procedure of isolation and cDNA synthesis and cloning from purified viral dsRNA. For subsequent RT-PCR detection of these and other viruses from tissue with high phenolic and polysaccharide concentrations, a simple and efficient extraction protocol for viral nucleic acid is also important. A method for rapid cDNA cloning from small amounts of purified dsRNA using a modification of degenerate oligo primed polymerase chain reaction mbox(DOP-PCR), and a modification of a protocol for effective extraction of viral RNA for use in RT-PCR are presented. Both methods were used to analyze a number of mottling diseases described in cherry. The causal agents for two of these diseases have been previously described, Cherry green ring Mottle virus, a tentative member of the foveaviruses, and Cherry Mottle leaf virus , a member of the trichoviruses. For the diseases cherry rusty Mottle and cherry necrotic rusty Mottle, data are presented identifying viruses associated with each disease. Viruses associated with cherry rusty Mottle, cherry necrotic rusty Mottle and European isolates of cherry Mottle leaf diseases, are closely related to Cherry green ring Mottle virus and can be tentatively included in the foveavirus genus. An additional virus, related to cherry green ring Mottle virus, was discovered by RT-PCR cloning and appears to be a common latent virus of cherry. Finally, isolates of cherry necrotic Mottle disease could be assayed positive by RT-PCR for a virus

  • Characterization and Detection of Several Filamentous Viruses of Cherry: Adaptation of an Alternative Cloning Method (DOP-PCR), and Modification of an RNA Extraction Protocol
    European Journal of Plant Pathology, 2001
    Co-Authors: M.e. Rott, Wilhelm Jelkmann
    Abstract:

    For the identification and analysis of new RNA plant viruses infecting fruit trees, an initial step often involves the laborious procedure of isolation and cDNA synthesis and cloning from purified viral dsRNA. For subsequent RT-PCR detection of these and other viruses from tissue with high phenolic and polysaccharide concentrations, a simple and efficient extraction protocol for viral nucleic acid is also important. A method for rapid cDNA cloning from small amounts of purified dsRNA using a modification of degenerate oligo primed polymerase chain reaction mbox(DOP-PCR), and a modification of a protocol for effective extraction of viral RNA for use in RT-PCR are presented. Both methods were used to analyze a number of mottling diseases described in cherry. The causal agents for two of these diseases have been previously described, Cherry green ring Mottle virus, a tentative member of the foveaviruses, and Cherry Mottle leaf virus , a member of the trichoviruses. For the diseases cherry rusty Mottle and cherry necrotic rusty Mottle, data are presented identifying viruses associated with each disease. Viruses associated with cherry rusty Mottle, cherry necrotic rusty Mottle and European isolates of cherry Mottle leaf diseases, are closely related to Cherry green ring Mottle virus and can be tentatively included in the foveavirus genus. An additional virus, related to cherry green ring Mottle virus, was discovered by RT-PCR cloning and appears to be a common latent virus of cherry. Finally, isolates of cherry necrotic Mottle disease could be assayed positive by RT-PCR for a virus