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  • 1
    Electronic Resource
    Electronic Resource
    Evidence for no relationship of the pineal activity with the neonatal shrinkage of Leydig cells in the rat (1984)
    Springer
    Cellular and molecular life sciences 40 (1984), S. 1155-1157 
    Details
    ISSN: 1420-9071
    Keywords: Leydig cell ; pineal gland ; neonate ; fetus, rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The collective volume of Leydig cells in prenatally pinealectomized newborn rats declined as sharply as in intact newborn rats. Also, the collective volume in pups born in the dark declined in a fashion similar to that in pups born in the light. The results indicate that neither the pineal gland nor the light is responsible for the neonatal shrinkage of Leydig cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01971470
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  • 2
    Electronic Resource
    Electronic Resource
    Studies on the fissure of cholesterol-pigment-calcium stone (multiple faceted stone) (1982)
    Springer
    Cellular and molecular life sciences 38 (1982), S. 1321-1322 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Multiple faceted gallstones with an internal fissure have been examined by gas chromatography-mass spectrometry. In vivo. the fissures probably contain only water vapor. The fissure may be produced by dehydration or water trapping during the stone formation process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01954927
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  • 3
    Electronic Resource
    Electronic Resource
    Fractionation of sulfur isotopes and selenium between coexisting sulfide minerals from the Besshi deposit, Central Shikoku, Japan (1984)
    Springer
    Mineralium deposita 19 (1984), S. 237-242 
    Details
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Fractionation of sulfur isotopes and selenium was measured between coexisting pyrite and chalcopyrite and between coexisting pyrrhotite and chalcopyrite from the Besshi deposit of Kieslager-type, Central Shikoku, Japan. In all the pyrite-chalcopyrite pairs studied, 34S is enriched in pyrite relative to chalcopyrite, while selenium is enriched conversely in chalcopyrite relative to pyrite. The mean △34Spy-cp value is +0.53±0.36 per mil, and the mean value of the distribution coefficient of selenium, Dcp-py, is 2.58±0.64. In all the pyrrhotite-chalcopyrite pairs studied, the two minerals are very close to each other both in sulfur isotope and Se/S ratios. The mean △34Spo-cp value is −0.08±0.16 per mil and the mean Dcp-po value is 0.99±0.05. The results have been discussed in comparison with similar data obtained for the Hitachi deposits of Kieslager-type, Japan (Yamamoto et al. 1983).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00199790
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  • 4
    Electronic Resource
    Electronic Resource
    Dimensional measurement of high aspect ratio micro structures with a resonating micro cantilever probe (2000)
    Springer
    Microsystem technologies 6 (2000), S. 179-183 
    Details
    ISSN: 1432-1858
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Technology
    Notes: Abstract  In non-destructive dimensional measurement of high aspect ratio micro structures (HARMS), optical methods cannot offer full three dimensional information due to the lack of observation light. Again, conventional mechanical measurement, such as a surface profiler or a coordinate measurement machine, cannot be applied because their stylus is too large. Furthermore, the AFM, though popular among the semiconductor industry, is also limited in terms of dimensional measurement, because its system is usually designed for planar samples. Thus, we have developed a new sensor-integrated micro resonating cantilever probe and a new dimensional measurement machine, which allows the probe's vertical access to microstructures in a sample. The new probe is made of tungsten carbide super hard alloy and possesses design flexibility according to its intended application. Validity of the system is confirmed through the measurement experiment of EDM drilled and chemically etched micro holes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005429900037
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  • 5
    Electronic Resource
    Electronic Resource
    Relationship between Se/S and sulfur isotope ratios of hydrothermal sulfide minerals (1976)
    Springer
    Mineralium deposita 11 (1976), S. 197-209 
    Details
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The pH and fO 2 dependences of the [Se2−]/[S2−] ratio in chloride solutions at 100°, 200° and 300°C are predicted thermodynamically. Under the high fO 2 conditions where sulfate species are dominant in solution, the [Se2−]/[S2−] ratio always increases with increasing pH and/or fO 2. Under the low fO 2 conditions where sulfide species are dominant in solution, the pH and fO 2 dependences of the [Se2−]/[S2−] ratio are seriously affected by the presence of native selenium. With native selenium present, the [Se2−]/[S2−] ratio decreases with increasing fO 2, but almost independent of pH in geologically important pH regions. When native selenium is absent, the [Se2−]/[S2−] ratio is solely a function of pH and independent of fO 2. Combining the above with the pH and fO 2 dependences of δ34S value of aqueous sulfur species, we discuss the possible influences of the pH and fO 2 of ore-forming solutions on the relationship between the Se/S ratio and δ34S value of hydrothermal sulfide minerals. The results are applied to some Japanese sulfide ore deposits.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00204481
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  • 6
    Electronic Resource
    Electronic Resource
    Simulation study on dynamics transition in neuronal activity during sleep cycle by using asynchronous and symmetry neural network model (1990)
    Springer
    Biological cybernetics 63 (1990), S. 243-250 
    Details
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Notes: Abstract We have found that single neuronal activities in different regions in the brain commonly exhibit the distinct dynamics transition during sleep-waking cycle in cats. Especially, power spectral densities of single neuronal activities change their profiles from the white to the 1/f along with sleep cycle from slow wave sleep (SWS) to paradoxical sleep (PS). Each region has different neural network structure and physiological function. This suggests a globally working mechanism may be underlying the dynamics transition we concern. Pharmacological studies have shown that a change in a wide-spread serotonergic input to these regions possibly causes the neuronal dynamics transition during sleep cycle. In this paper, based on these experimental results, an asynchronous and symmetry neural network model including inhibitory input, which represents the role of the serotonergic system, is utilized to examine the reality of our idea that the inhibitory input level varying during sleep cycle induce that transition. Simulation results show that the globally applied inhibitory input can control the dynamics of single neuronal state evolution in the artificial neural network: 1/f-like power spectral density profiles result under weak inhibition, which possibly corresponds to PS, and white profiles under strong inhibition, which possibly corresponds to SWS. An asynchronous neural network is known to change its state according to its energy function. The geometrical structure of network energy function is thought to vary along with the change in inhibitory level, which is expected to cause the dynamics transition of neuronal state evolution in the network model. These simulation results support the possibility that the serotonergic system is essential for the dynamics transition of single neuronal activities during sleep cycle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00203447
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  • 7
    Electronic Resource
    Electronic Resource
    Further study on 1/f fluctuations observed in central single neurons during REM sleep (1993)
    Springer
    Biological cybernetics 68 (1993), S. 193-198 
    Details
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Notes: Abstract Recently, 1/f fluctuations have been discovered in the single-unit activity of mesencephalic reticular formation (MRF) neurons during REM sleep. In a previous paper, such behavior could satisfyingly be interpreted on the basis of the clustering Poisson process. The question of applicability of this model to other MRF neurons remained unanswered. The present paper reports on 1/f fluctuations in 12 MRF neurons all of which can satisfyingly be modeled by the clustering Poisson process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00224851
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  • 8
    Electronic Resource
    Electronic Resource
    Statistical dependency as a measure to evaluate Markov properties of stochastic point processes (1975)
    Springer
    Biological cybernetics 18 (1975), S. 191-208 
    Details
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Notes: Abstract Neuronal spike trains are regarded as stochastic point processes. To estimate the order and value of Markov processes of the interspike interval sequences with small number of samples, we have proposed a new measure of simplified statistical dependencyd m. This measure is derived from statistical dependencyd m (T=τ) in the case of Gaussian process, and is obtained by the standard deviation and the matrices of the serial correlation coefficients. Sinced m is a parametric measure, it is calculated from the interval sequence transformed into the aormal distribution. We designate this as normalized simplified statistical dependencyNd m. The order and value of the maintained spike sequences recorded from the mesencephalic reticular formation, red nucleus, optic tract, and lateral geniculate nucleus neurons in cats have been estimated. It is indicated that there is a considerable correspondence between the value ofNd m and that ofd m (T=τ). This suggests thatNd m is useful in practice to estimate the order and value of Markov process with small number of samples.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00326689
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  • 9
    Electronic Resource
    Electronic Resource
    Dependency as a measure to estimate the order and the values of Markov processes (1977)
    Springer
    Biological cybernetics 25 (1977), S. 209-226 
    Details
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Notes: Abstract To evaluate the order and the values of Markov properties of the time series of events, we have proposed a statistical measure “dependency”:D m = (H 0 −H m )/H 0 , whereH 0 andH m are Shannon's entropy and them-th order conditional entropy, respectively. It is indicated that $$\tilde D_m = \sum\limits_{v = 1}^m {(\hat D_v - \bar D_v^{sh} } )$$ is a better point estimator ofD m, giving a total value of them-th order Markov process. Here $$\hat D_m $$ and $$\bar D_m^{sh} $$ are the estimate ofD m and the arithmetic mean of $$\hat D_m^{sh} $$ when them-th order shuffling is made many times for a given observed series, respectively. The value $$\hat D_m - \bar D_m^{sh} = d_m $$ represents Markov value of the orderm. Under the assumption that the series has continuous variables and the normal distribution, simplified dependency is defined by , where |S m | is the determinant of serial correlation coefficients. It is shown that is practically useful for the estimation of the order and the values of Markov processes with small sample size. It is also indicated that analysis is basically equivalent to the least mean-square analysis of autoregressive models.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01885639
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  • 10
    Electronic Resource
    Electronic Resource
    An interpretation of 1/f fluctuations in neuronal spike trains during dream sleep (1989)
    Springer
    Biological cybernetics 60 (1989), S. 161-169 
    Details
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Notes: Abstract The mesencephalic reticular formation (MRF) neurons are regarded as contributing to the activation of the cerebral cortex. We have investigated the statistical characteristics of the single neuronal activity in the MRF of cat during two activated states: paradoxical sleep (PS) and state in which the animal is watching birds (BW). 1/f-like spectra are observed for both PS and BW states, being more pronounced for PS state. For the interpretation of these findings, we have applied the clustering Poisson process, which not only gives rise to a 1/f spectrum but also suggests a generation mechanism. The MRF neuronal activities in PS and BW are closely fitted by the clustering Poisson process, both in terms of power spectral density and counting statistics. These results strongly suggest that the activities of MRF neurons in PS and BW can be interpreted as the superpositions of randomly occurring clusters which consist of various number of impulses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00207284
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