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71.
Hilairet N Reynard B Wang Y Daniel I Merkel S Nishiyama N Petitgirard S 《Science (New York, N.Y.)》2007,318(5858):1910-1913
The supposed low viscosity of serpentine may strongly influence subduction-zone dynamics at all time scales, but until now its role could not be quantified because measurements relevant to intermediate-depth settings were lacking. Deformation experiments on the serpentine antigorite at high pressures and temperatures (1 to 4 gigapascals, 200 degrees to 500 degrees C) showed that the viscosity of serpentine is much lower than that of the major mantle-forming minerals. Regardless of the temperature, low-viscosity serpentinized mantle at the slab surface can localize deformation, impede stress buildup, and limit the downdip propagation of large earthquakes at subduction zones. Antigorite enables viscous relaxation with characteristic times comparable to those of long-term postseismic deformations after large earthquakes and slow earthquakes. Antigorite viscosity is sufficiently low to make serpentinized faults in the oceanic lithosphere a site for subduction initiation. 相似文献
72.
Miyuki KITAOKA Shuichi HIRAI Hayato TERAYAMA Munekazu NAITO Ning QU Naoyuki HATAYAMA Hidenobu MIYASO Yoshiharu MATSUNO Masatoshi KOMIYAMA Masahiro ITOH Chisato MORI 《The Journal of reproduction and development》2013,59(5):485-490
Exposure to di-(2-ethylhexyl) phthalate (DEHP) has been reported to induce
spermatogenic disturbance through oxidant stress and affect the immune system as an
adjuvant. However, the effect of DEHP on the testicular immune microenvironment has
not yet been investigated. In the present study, we examined the testicular immune
microenvironment after exposure to doses of DEHP, previously identified as
no-observed-adverse-effect levels. Adult male mice were administered food containing
0%, 0.01% or 0.1% DEHP and then testes were analyzed. The results showed that a
slight but significant spermatogenic disturbance appeared in the 0.1% DEHP group but
not in the 0.01% DEHP group at 8 weeks. It was also demonstrated that lymphocytes and
F4/80- and MHC class II- positive cells were significantly increased with the
elevation of IL-10 and IFN-γ mRNA expressions in the testes of not only the 0.1% DEHP
group but also the 0.01% DEHP group at 8 weeks. Histochemical analyses involving
horseradish peroxidase (HRP) as a tracer showed that a little blood-borne HRP had
infiltrated into the lumen of a few seminiferous tubules beyond the
blood-testis-barrier in both the 0.1% and 0.01% DEHP groups at 8 weeks. This
indicates that a dose of DEHP that has little effects on spermatogenesis can change
the testicular immune microenvironment with functional damage of the blood-testis
barrier. 相似文献
73.
Chisato YONEMOCHI Hirokazu FUJISAKI Chisato HARADA Toyoko KUSAMA Michito HANAZUMI 《Animal Science Journal》2002,73(3):221-228
The influence of transgenic event CBH 351 (StarLink; SL)-derived hybrid corn on the growth performance, health condition and physiological function in broiler chicks, as well as the possible transfer of the cry9C gene and Cry9C protein to blood, liver and muscle were examined in comparison with chicks fed on a diet with non-transgenic corn (SL-F). Bodyweight gain and feed conversion ratio in the chicks fed on a diet with SL were significantly greater than in chicks fed on a diet with SL-F during the starter phase (0–3 weeks of age), but this significant difference disappeared during the finisher phase (4–7 weeks of age). No abnormalities in health condition in either SL or SL-F groups were observed, and livability did not differ significantly between SL and SL-F groups. Moreover, no significant differences in serum biochemical and hematological values, histopathological observation and necropsy findings were observed between SL and SL-F groups at the end of the experiment. The cry9C gene and Cry9C protein were not detected in blood, liver and muscle of chicks at 3, 5 or 7 weeks of age. The results indicate that feeding SL does not influence growth performance, health condition or physiological function in broiler chicks, and the cry9C gene and Cry9C protein are not transferred to the blood, liver and muscles of broilers. 相似文献
74.
The immunoglobulin G (IgG)-containing B lymphocyte antigen receptor (IgG-BCR) transmits a signal distinct from that of IgM-BCR or IgD-BCR, although all three use the same signal-transducing component, Igalpha/Igbeta. Here we demonstrate that the inhibitory coreceptor CD22 down-modulates signaling through IgM-BCR and IgD-BCR, but not that through IgG-BCR, because of the IgG cytoplasmic tail, which prevents CD22 phosphorylation. These results suggest that the cytoplasmic tail of IgG specifically enhances IgG-BCR signaling by preventing CD22-mediated signal inhibition. Enhanced signaling through IgG-BCR may be involved in efficient IgG production, which is crucial for immunity to pathogens. 相似文献
75.
Abul Kalam Mohammad Azmal Takuya Marumoto Haruo Shindo Masaya Nishiyama 《Soil Science and Plant Nutrition》2013,59(3):463-473
A model experiment was carried out at 15, 25, and 35°C to investigate the changes in microbial biomass and the pattern of mineralization in upland soil during 8 weeks following the addition of 8 organic materials including 6 tropical plant residues, ipil ipil (Leucaena leucocephala), azolla (Azolla pinnata), water hyacinth (Eichhornia crassipes), dhaincha (Sesbania rostrata), cowpea (Vigna unguiculata), and sunhemp (Crotalaria juncea). The amounts of CO2-C evolved and inorganic N produced at 35°C were about 2 times larger than those at 15°C. At any temperature, the flush decomposition of C was observed within the first week and thereafter the rate of mineralization became relatively slow. A negative correlation was observed between inorganic N and C/N ratios of the added organic materials. The relationships between the amounts of cellulose or cellulose plus hemicellulose and the amount of mineralized N of the added organic materials were also negative. The changes in the microbial biomass were affected by temperatures. The amount of biomass C and N was maximum after 42 d of incubation at 15°C, and after 7 d at 25 and 35°C, and thereafter decreased. The rate of biomass decline was slower at 15°C and faster at 35°C than at 25°C. Regardless of the temperatures, the addition of organic materials enhanced microbial biomass formation throughout the incubation periods. 相似文献
76.
Yoshio Aikawa Iwao Nagano Shunjiro Sakamoto Masaya Nishiyama Satoshi Matsumoto 《Soil Science and Plant Nutrition》2013,59(4):835-842
Scopelophila ligulata (Spruce) Spruce, S. cataractae (Mitt.) Broth., and Mielichhoferia japonica Besch. (Mielichhoferia mielichhoferi (Hook.) Wijk et Marg. var. japonica (Besch.) Wijk et Marg.) are well known “copper mossess” which show peculiar ecological characteristics consisting of a preference for metal-rich soils, lithosols, rocks, etc. as their substrates. The total and water-soluble element contents in the substrates and heavy metal contents in the moss body were analyzed in this study. The results of these chemical analyses were as follows: The iron contents in the moss body and substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary the copper contents of the former were lower than those of the latter. The pH values of substrate of S. ligulata were lower than those of S. cataractae and M. japonica. The concentrations of water-soluble iron and sulfate in the substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary, the water-soluble copper concentrations in the substrate of S. ligulata were lower than those of the others. Although in the substrate of S. cataractae the iron content was several times higher than the copper content, in the moss body the copper content was higher than iron content. 相似文献
77.
A simplified method has been developed for designing and calculating sprinkling systems by cutting lines across laterals at
points next to the first sprinkler with a view to divide the system into two separate parts; field and basic. Equations of
lateral pressure heads were used to express the relationship between inlet pressure head and velocity of the flow pumped to
laterals on the field part. The above equations were then used to set up calculating conditions for the Basic part by unsteady
flow method in order to define head and discharge at downstream end of the pipe in the Basic part. The forward step method
was used for determining distributions of the pressure head and the emitter discharge along each lateral. A calculating schema
on computer has been carried out in order to apply the method to any sprinkling system. The procedure of analysis and calculation
showed that this method is generally accurate, simple and rapid. 相似文献
78.
This paper examines the increasingly popular chisan-chisho movement that has promoted the localization of food consumption in Japan since the late-1990s. Chisan-chisho emerged in the
context of a perceived crisis in the Japanese food system, particularly the long-term decline of agriculture and rural community
and more recent episodes of food scandals. Although initially started as a grassroots movement, many chisan-chisho initiatives
are now organized by governments and farmers’ cooperatives. Acknowledging that the chisan-chisho movement has added some important
resources and a conceptual framework, we nonetheless point out that chisan-chisho has been refashioned as a producer movement
by government as well as the Japan Agricultural Cooperative, capitalizing on local food’s marketing appeal. Chisan-chisho
to date has not been able to become a full-fledged citizen-based political mobilization nor address the issue of marginality
in the food system.
相似文献
Aya Hirata KimuraEmail: |
79.
Tadashi Ogawa Chisato Matsumoto Chisato Takenaka Takafumi Tezuka 《Journal of Forest Research》2000,5(2):81-85
The effect of CA(NO3)2 on the active oxygen scavenging system in hinoki cypress (Chamaecyparis obtusa) seedlings cultured in a nutrient solution containing aluminum was examined. The hinoki cypress seedlings were transferred
to nutrient solutions containing 5 mM AlCl3 together with various concentrations of Ca(NO3)2 in pots containing glass beads and Teflon tips. The growth in height and dry matter allocation to each organ was little influenced
over a period of 12 weeks by either Al or the concentration of Ca(NO3)2. The activity of superoxide dismutase (SOD) in the needles was stimulated by Al, and the effect of Al was lowered significantly
by simultaneous application of 25 mM Ca(NO3)2. At week 1, the activity of catalase (CAT) in the needles was increased by Al, but the effect was no longer observed at week
12. The Al concentration in the roots was increased by treatment with Al, whereas the Al concentration in needles was not.
These results indicate that rhizospheric Al stress stimulates antioxidative enzyme activities in hinoki cypress needles and
the activation of the enzymes is suppressed by addition of Ca. The transmission of Al stress to the needles, which induced
a change in the enzyme activity, is not caused by the transfer of the Al ion itself from roots to needles.
This work was supported in part by funding from the Japan Science and Technology Corporation, the CREST program 1996–2001,
and the Center for Forest Decline Studies. 相似文献
80.
Wataru Ohkawa Yoshinori KanayamaNaoko Daibo Takahiro SatoManabu Nishiyama Koki Kanahama 《Scientia Horticulturae》2010
Studies on the metabolic process of photoassimilates and enhancement of sugar accumulation into fruit are important in fruit crop production. The metabolic process of the 14C-photoassimilates in cucumber plants was analyzed with respect to the vascular system. At 4 h after the start of 14CO2 feeding, the 14C-photoassimilates synthesized in a selected leaf on the main shoot were translocated to the vascular bundles of the internode just below the 14CO2-fed leaf. The radioactivity of 14C-stachyose was as high as that of 14C-sucrose in the vascular bundles of petiole and internode just below the 14CO2-fed leaf as well as in the midrib, while the radioactivity of 14C-stachyose was lower than that of 14C-sucrose in the mesophyll. The 14C-photoassimilates appeared to have been translocated without any metabolic change in the translocation pathways between the petiole and internode just below the 14CO2-fed leaf, because the ratio of 14C-stachyose radioactivity in the two parts was similar. At 8 h after the start of 14CO2 feeding, the 14C-photoassimilates were translocated to the fruit. In the vascular bundles of the peduncle, the ratios of the radioactivity of 14C-stachyose and 14C-raffinose were lower, and the ratio of the radioactivity of 14C-sucrose was higher, than that at the petiole and internode just below the 14CO2-fed leaf at 8 h after the start of 14CO2 feeding. Therefore, it seemed that 14C-stachyose and 14C-raffinose were hydrolyzed to 14C-sucrose in the peduncle. 相似文献