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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Adsorption 1 (1995), S. 165-173 
    ISSN: 1572-8757
    Keywords: He adsorption ; micropore ; ultramicroporosity ; N2 adsorption ; zeolite
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The density of He adsorbed in the cylindrical micropores of zeolites NaY and KL has been determined by He adsorption at 4.2K. He adsorption isotherms were then compared with N2 adsorption isotherms at 77K. Crystallographic considerations of the micropore volumes gave the density of the He adsorbed layer, which is necessary for assessment of ultramicroporosity of less-crystalline microporous solids, such as activated carbons. The determined density of He adsorbed in the cylindrical micropores of the zeolite was in the range 0.22 to 0.26 gml−1, greater than that of He adsorbed on a flat surface (0.202 gml−1). A value for the density of He between 0.20 to 0.22 gml−1 is recommended for evaluation of ultramicroporosity of a slit-shaped microporous system such as activated carbon.
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  • 2
    ISSN: 1432-1254
    Keywords: Heart rate ; Oxygen saturation ; Recovery stage ; Hypoxia ; HRmax
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Abstract Physiological changes were investigated in the cardio-respiratory function of competitors in a bicycle race which involved not a flat course but ascending a mountain, from 1400m to 2800m. Heart rate throughout the race, arterial oxygen saturation and pulmonary function before and after the race of well trained competitors were measured. The individual's maximal heart rate during the race was designated as HRmax for the calculations. (1) There were significant correlations between the age and the mean %HRmax during the race, between mean %HRmax and time, and between age and time (n=15); the mean %HRmax had a 3.90 times greater effect on time than did age. (2) The individuals who performed best had lower values of oxygen saturation just after finishing the race (n=51). (3) At 1 min after reaching the finishing line, oxygen saturation levels had recovered to the value of 20 min after finishing the race, whereas the heart rate was still in the process of recovery (n=18). (4) Maximum expiratory flow at 50% vital capacity measured 30 min after reaching the finishing line was significantly higher than at the starting point. The intensity of the load on the cardiac system produced by completion of this course was estimated to be almost the same as that of a full marathon on a flat course. The time depended on both the youth of the cyclist and on his ability to maintain a high value of %HRmax during the race.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    International journal of game theory 24 (1995), S. 127-145 
    ISSN: 1432-1270
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Abstract When perfect recall is not satisfied, the informational contents of mixed and behavior strategies differ and are more than what the information partition describes. First, we consider two kinds of additional information strategies may carry, and show that such information leads to theperfect recall refinement of a given information partition. This does not, however, imply that the strategies compensate fully for the lack of perfect recall. We give a necessary and sufficient condition on an information partition, calledA-loss, for the informational content of mixed strategies to fully compensate for the lack of perfect recall. The informational content of behavior strategies never fully compensates.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Shock waves 5 (1995), S. 127-138 
    ISSN: 1432-2153
    Keywords: Impulsive pressure wave ; Piston problem ; Perforated wall ; Railway tunnel ; Shock wave generation ; Sonic boom
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics , Technology
    Notes: Abstract Upon the entrance of a high-speed train into a relatively long train tunnel, compression waves are generated in front of the train. These compression waves subsequently coalesce into a weak shock wave so that a unpleasant sonic boom is emitted from the tunnel exit. In order to investigate the generation of the weak shock wave in train tunnels and the emission of the resulting sonic boom from the train tunnel exit and to search for methods for the reduction of these sonic booms, a 1∶300 scaled train tunnel simulator was constructed and simulation experiments were carried out using this facility. In the train tunnel simulator, an 18 mm dia. and 200 mm long plastic piston moves along a 40 mm dia. and 25 m long test section with speed ranging from 60 to 100 m/s. The tunnel simulator was tilted 8° to the floor so that the attenuation of the piston speed was not more than 10 % of its entrance speed. Pressure measurements along the tunnel simulator and holographic interferometric optical flow visualization of weak shock waves in the tunnel simulator clearly showed that compression waves, with propagation, coalesced into a weak shock wave. Although, for reduction of the sonic boom in prototype train tunnels, the installation of a hood at the entrance of the tunnels was known to be useful for their suppression, this effect was confirmed in the present experiment and found to be effective particularly for low piston speeds. The installation of a partially perforated wall at the exit of the tunnel simulator was found to smear pressure gradients at the shock. This effect is significant for higher piston speeds. Throughout the series of train tunnel simulator experiments, the combination of both the entrance hood and the perforated wall significantly reduces shock overpressures for piston speeds ofu p ranging from 60 to 100 m/s. These experimental findings were then applied to a real train tunnel and good agreement was obtained between the tunnel simulator result and the real tunnel measurements.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Marine biology 122 (1995), S. 165-170 
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To evaluate the osmoregulatory ability of eyedstage embryos of laboratory-reared chum salmon, Oncorhynchus keta, we examined changes in osmolality of the perivitelline fluid and blood following transfer to 50 and 100% seawater (SW), together with morphological changes in chloride cells present in the yolk sac membrane. Transfer to SW did not cause any significant change in the whole egg weight. However, the embryos shrank when the eggs were transferred to SW, whereas the perivitelline space increased at the expense of the embryo. Osmolality of the perivitelline fluid increased rapidly to reach environmental levels 3 h after transfer, indicating that the egg shell is permeable to ions and water. Blood osmolality increased after transfer to SW, reached a peak level at 3 h, and then decreased gradually. The chloride cells in the yolk sac membrane became activated following transfer, as shown by increased cell size and frequent appearance of apical openings. These results indicate that the eyed-stage embryos of chum salmon possess hypoosmoregulatory ability and that chloride cells in the yolk sac membrane may be involved in salt extrusion, in place of gill chloride cells, during the late embryonic stage.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Few body systems 18 (1995), S. 1-24 
    ISSN: 1432-5411
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. The multi-configuration resonating-group method is employed to study the properties of the three-nucleon system. The model space is spanned by p+d, p+d', n+ 2p, and a large number of their associated pseudo-inelastic configurations. The nucleon-nucleon potential used is the Minnesota potential which contains nuclear central, Coulomb, and spin-orbit components. The results show that the calculated p+d complex phase shifts agree well with the values obtained by an empirical analysis of experimental data. Differential scattering and total reaction cross sections in the p+d system are calculated at centre-of-mass energies up to 32 MeV. Without adjusting any parameter, it is found that the agreement between calculation and experiment is quite satisfactory. The effects of successively enlarging the model space have also been examined. Here the finding is that, in order to obtain reliable results, all three types of cluster configurations must be included in the calculation.
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  • 7
    ISSN: 1432-2048
    Keywords: Chaetomorpha ; Cold treatment ; Cortical microtubule ; Immunofluorescence ; Microtubule assembly
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of cold treatment on the cortical microtubules (MTs) of Chaetomorpha moniligera Kjellman were investigated by immunofluorescence microscopy. Cortical MTs in Chaetomorpha thallus are arranged longitudinally. In this study, 70–75% of MTs disassembled within 4 h on ice while the others remained stable under these conditions. Reticulate background immunofluorescence, assumed to indicate the presence of a tubulin monomer, was distributed about the stable MTs. Immunofluorescence was prominent in only 50% of the cells. Tubulin polymerization was noted where the background and MT immunofluorescence was strong. New MTs grew transversely as single strings or clusters from the sides of MTs after cold treatment for 4 h and elongated with time to take on a reticulate form at 24 h. The significance of this tubulin polymerization under cold treatment is discussed.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Planta 196 (1995), S. 477-484 
    ISSN: 1432-2048
    Keywords: Amyloplast ; Endosperm ; Immunolocalization ; Metabolite transport ; Starch Synthesis ; Zea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A chimeric protein, formed of 56 amino acids from the carboxy terminus of the maize (Zea mays L.) wild-type Brittle1 (Bt1) protein fused to the glutathione-S-transferase gene, was synthesized in Escherichia coli, and used to raise antibodies. Following affinity purification, the antibodies recognized a set of 38-to 42-kDa proteins in endosperm from wild-type Bt1 plants, as well as from brittle2, shrunken2 and sugary1 plants, but not in mutant bt1 endosperm. Bt1 proteins were not detected with the preimmune antibodies. A low level of Bt1-specific proteins was detected at 10 d after pollination (DAP) and increased to a plateau at 16 DAP. At the same time, the ratio of slow to fast-migrating forms of the protein decreased. During endosperm fractionation by differential centrifugation and membrane sedimentation in sucrose gradients, the Bt1 proteins co-purified with the carotenoid-containing plastid membranes. They were localized to amyloplasts by electron-microscopic immunocytochemistry; most of the signal was detected at the plastid periphery. These results are consistent with predictions made from the deduced amino-acid sequence and previous in-vitro experiments that the bt1 locus encodes amyloplast membrane proteins.
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  • 9
    ISSN: 1432-0878
    Keywords: Pineal organ ; Neuron-specific enolase ; Immunohistochemistry ; Three-dimensional reconstruction ; Post-hatching development ; Domestic fowl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Immunohistochemistry for neuron-specific enolase (NSE) revealed that NSE is localized in both a limited number of pinealocytes and intrinsic afferent neurons in the pineal organ of the domestic fowl. Furthermore, a computer-assisted three-dimensional imaging technique allowed to clarify the reverse distributional pattern of both elements: NSE-positive pinealocytes displayed a dense distribution especially in the vesicular portion of the gland, whereas NSE-immunoreactive nerve cells were mainly found in the pineal stalk. The number of NSE-positive intrinsic neurons in the pineal organ of chickens decreased rapidly after hatching, with a concentration of these elements in the basal portion (stalk) of the pineal organ. On the other hand, immunoreactive pinealocytes increased remarkably in the end-vesicle of the organ with age, followed by a gradual expansion toward the proximal portion. Thus, the spectacular increase in NSE-positive pinealocytes and the progressive reduction of reactive neurons occurred in parallel during the course of post-hatching development. NSE-immunoreactive pinealocytes displayed morphological characteristics of bipolar elements, endowed with an apical protrusion into the pineal lumen and a short basal process at younger stages, whereas multipolar types of NSE-positive pinealocytes were predominantly found in the adult domestic fowl. These results indicate that in the pineal organ of the domestic fowl (1) the ontogenetic expansion of NSE-immunoreactive pinealocytes is paralleled by a regressive afferent innervation, (2) the NSE-positive pinealocytes transform from a bipolar (columnar) type to a multipolar type during post-hatching development, and (3) these ontogenetic changes in the NSE-immunoreactivity and morphology of pinealocytes may reflect the development of a neurosecretory-like capacity of the organ.
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  • 10
    ISSN: 1432-0878
    Keywords: Osteoclasts ; Bone resorption ; Acid phosphatase ; Capillary network ; Rainbow trout, Oncohynchus mykiss (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Mineral-containing bone particles (BPs) were implanted intramuscularly into rainbow trout (Oncorhynchus mykiss) to investigate the sequence of appearance of bone-resorbing cells. A fibrous substance first surrounded the implanted BPs and was gradually replaced by connective tissue containing capillaries. Two weeks after BP implantation, relatively small multinucleated cells (type-1 cells), whose cytoplasm stained deeply with hematoxylin, appeared along the surfaces of the BPs. At later stages (after 4–8 weeks), the majority of cells which appeared to be resorbing the BPs were multinucleated cells whose cytoplasm stained deeply with eosin (type-2 cells). Type-2 cells contained more nuclei than type-1 cells. Electron-microscopical observations revealed that type-2 cells had the characteristic features of osteoclasts: the presence of numerous mitochondria, vacuoles and granules, and a differentiation of the cell membrane and cytoplasm into a ruffled border and clear zone, respectively. A tartrate-resistant acid phosphatase activity, which is an established characteristic of osteoclasts in terrestrial vertebrates, but which had not previously been examined in teleosts, was demonstrated histochemically in the type-2 cells. Development of type-2 cells was closely correlated with the development of connective tissue. These findings suggest that the development of a capillary network around the implanted BPs enables circulating osteoclast-progenitors to reach the surface of the BPs.
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