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41.
Kenji UCHIDA Masahiro HIRATA Hidemasa MOTOSHIMA Tadasu URASHIMA Ikichi ARAI 《Animal Science Journal》2007,78(6):650-658
The traditional fermented dairy products were collected from three nomadic families in Donto‐Govi prefecture in Mongolia (central Mongolia), and those microbiota were analyzed. These samples consist three of ‘airag’, two of ‘tarag’, two of ‘isgelen tarag’ and ‘qoormog’, and some cheeses. In airag, Lactobacillus (L.) helveticus, L. kefiri, and Saccharomyces (S.) dairensis were common, and L. paracasei, L. plantarum, L. farciminis, S. cerevisiae, Issachenkia (I.) orientalis, Kluyveromyces (K.) wickerhamii were also found. In tarag, isgelen tarag and qoormog, L. helveticus, L. kefiri, L. fermentum, L. paracasei and L. acetotolerance were found. L. delbrueckii subsp. bulgaricus was also found in one tarag and one qoormog samples. Randomly amplified polymorphic DNA (RAPD) analysis showed that there were diversity in each L. helveticus family and products, and there were common strains found in airag and tarag in the same family. 相似文献
42.
Nobuhito Mitani Shozo Kobayashi Yoko Nishizawa Takeshi Kuniga Ryoji Matsumoto 《Scientia Horticulturae》2006
RCC2, cDNA clone encoding rice class-I chitinase, was introduced into trifoliate orange (Poncirus trifoliata Raf.). Chitinase activity of the transformed plants was higher than that of the non-transformed plants. The introduced gene was not detected in the scions grafted onto the transformed plants. The effect of the introduction of foreign gene into rootstocks on the scions was discussed. 相似文献
43.
Japanese red pine (Pinus densiflora) seedlings taken from a nursery were grown in liquid culture with all roots entirely submerged in water. The aims of the present study were to observe the reactions of preformed ectomycorrhizae to liquid culture and to examine new infections by ectomycorrhizal fungi on newly formed root tips in liquid culture. Inoculation levels were controlled by trimming the ectomycorrhizal roots to one of three selected root lengths. The results showed that the mantles of pre-formed ectomycorrhizae were lost during the 8 weeks of the liquid culture and that these preformed root tips became blackish and wrinkled, but Hartig nets remained in these blackish root tips. On the newly formed lateral root tips, no ectomycorrhizal mantles were formed, although Hartig nets were found. In addition, the level of inoculum did not affect the frequency of Hartig nets in newly formed root tips, suggesting that the density of inoculum was more important than the amount of inoculum for new infection. In conclusion, ectomycorrhizal fungi endured and infected new roots while submerged; however, only Hartig nets were formed and not mantles. 相似文献
44.
Kenji Ono Motohiro Hasegawa Makoto Araki Masahiro Amari Masakazu Hiraide 《Journal of Forest Research》2007,12(4):255-261
We examined the relationships between the absorptional characteristics in the near infrared region and the chemical changes
of decomposing beech (Fagus crenata) and pine (Pinus densiflora) litters. Spectra as well as the concentrations of chemical substances approached each other and converged with decomposition,
although both initial characteristics differed markedly between beech and pine. This indicated that the fundamental chemical
structures were almost the same, although their organochemical composition differed. Specific absorption bands for lignin,
polysaccharide, and protein were identified at 2,140 and 1,670 nm, 2,270, 1,720, 1,590, and 1,216 nm, and 2,350 nm, respectively.
Absorbance at 1,670 nm, peculiar band of aromatics, showed a positive correlation with lignin concentration, which suggested
the relative increment of aromatics due to condensed lignin in decomposing litters. Absorbance at 2,140 nm, characterized
as the C–H bond in HRC = CHR, showed a negative correlation with lignin concentration, which suggested the decrements of some
structures such as side-chains in lignin polymers unrelated to aromatics. Absorbance at 2,270, 1,720, and 1,216 nm, specified
to O–H/C–O/C–H bonds in saccharide, might reflect the change of polysaccharide during decomposition because they showed a
positive correlation to polysaccharide concentration. In the same way, absorbance at 2,350 nm, identified to the C–H/CH2 bonds in protein, showed a negative correlation to nitrogen concentration in decomposing litters, which might indicate that
the C–H/CH2 bonds in protein decreased with decomposition due to microbial consumption of carbon in protein. Our findings suggested the
possibility that the spectral changes indicate the litter digestibility during decomposition and that also explain the compositional
change in decomposing litters. 相似文献
45.
Dede Hermawan Toshimitsu Hata Kenji Umemura Shuichi Kawai Wakatsu Nagadomi Yasuo Kuroki 《Journal of Wood Science》2001,47(4):294-300
This study deals with the effects of curing treatment with gaseous and supercritical carbon dioxide on the properties of cement-bonded particleboard (CBP) manufactured by the conventional cold-pressing method. The hydration of cement and the mechanism of improvement were examined using X-ray diffractometry (XRD), thermal gravimetry (TG-DTG), and scanning electron microscopy (SEM) observations. The results are as follows: (1) The curing of cement was accelerated concomitantly with the improvement in mechanical and dimensional properties of CBP significantly by curing with gaseous or supercritical carbon dioxide. (2) Supercritical carbon dioxide curing imparted boards optimal properties at a faster rate than did gaseous curing. (3) Accelerated formation of calcium silicate hydrate and calcium carbonate and the interlocking of those hydration products on the wood surface are potentially the main reasons for the superior strength of carbon dioxide-cured boards. 相似文献
46.
Toshihiro Hata Kenji Umemura Hidefumi Yamauchi Akihiro Nakayama Shuichi Kawai Hikaru Sasaki 《Journal of Wood Science》2001,47(2):115-123
A new spiral-winder was developed for continuous manufacturing of cylindrical laminated veneer lumber (LVL), and a suitable resin adhesive for this cylindrical LVL manufacturing system was investigated. This phase was followed by trial manufacturing and evaluation of cylindrical LVL with the optimum resin adhesive identified. The results are summarized as follows. (1) The shortest gelation time was recorded with a mixture of two commercial resorcinol based resins (DF-1000 and D-33) at a weight ratio of 2575. (2) Bath temperature had a remarkable effect on the gelation time of the adhesive mix. (3) High bonding strength was recorded by 2575 DF-1000/D-33 adhesive mix at a high press temperature despite a short pressing duration. Based on the results of items (1) to (3), 2575 DF-1000/ D-33 is recommended for use in the new spiral-winder. (4) The mechanical properties of cylindrical LVL could be improved by using 2575 DF-1000/D-33 with wider veneer width and longer pressing time. (5) The mechanical properties, especially the modulus of rupture, of the cylindrical LVL manufactured require further improvement for practical structural application. 相似文献
47.
Kenaf (Hibiscus cannabinus) plants are widely known for their contribution to the global and regional environment because of their ability to fix CO2. On the other hand, some scientists have doubts about CO2 fixation by kenaf and have misgivings about the effect of kenaf on the ecosystem. We have characterized the structural characteristics
of cell walls of bast fibers, cores, roots, and leaves of kenaf during the maturation of plants and investigated the rate
of photosynthesis. During maturation of the kenaf plant the cellulose (bast fiber 52–59%, core 44–46%) and lignin (bast fiber
9.3–13.2%, core 18.3–23.2%) contents increased significantly. The aromatic composition of the lignin of bast fiber was significantly
different from that of the core lignin and of other plants. The lignin of bast fiber appears similar to pure syringyl lignin.
Fixation of CO2 by kenaf plants and their contribution to the global environment are discussed. A significatly high rate of photosynthesis
of kenaf plants was observed compared to that of woody plants in Japan, but the amount of CO2 fixation depends on the characteristics of the plantation. If the kenaf was planted in high density, about twice as much
CO2 was fixed as was fixed by trees in a tropical rain forest.
Received: April 22, 2002 / Accepted: July 24, 2002
Acknowledgments This project was supported by the Science and Technology Agency (STA) fellowship of the Japan International Science and Technology
Exchange Center (JISTEC), which has been successfully applied by Dr. Shuji Hosoya, Forestry and Forest Products Research Institute.
We thank Dr. Toshio Sumizono and Mr. Masao Sakurai, Forestry and Forest Products Research Institute, for their kind help in
determining the rate of photosynthesis and cultivating the kenaf plants, respectively. We also express our appreciation to
Dr. Quang Hung Le, College of Agriculture and Forestry, Ho Chi Minh City, Vietnam for offering information about the cultivation
of kenaf at Thu Duc District, Ho Chi Minh City. 相似文献
48.
Rei NAKANO Kazuya EDAMURA Tomohiro NAKAYAMA Kenji TESHIMA Kazushi ASANO Takanori NARITA Ken OKABAYASHI Hiroshi SUGIYA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):27-35
We investigated the in
vitro differentiation of canine bone marrow stromal cells (BMSCs) into voltage-
and glutamate-responsive neuron-like cells. BMSCs were obtained from the bone marrow of
healthy beagle dogs. Canine BMSCs were incubated with the basal medium for neurons
containing recombinant human basic fibroblast growth factor (bFGF; 100
ng/ml). The viability of the bFGF-treated cells was
assessed by a trypan blue exclusion assay, and the morphology was monitored. Real-time
RT-PCR was performed to evaluate mRNA expression of neuronal, neural stem cell and glial
markers. Western blotting and immunocytochemical analysis for the neuronal markers were
performed to evaluate the protein expression and localization. The Ca2+
mobilization of the cells was evaluated using the Ca2+ indicator Fluo3 to
monitor Ca2+ influx. To investigate the mechanism of bFGF-induced neuronal
differentiation, the fibroblast growth factor receptor inhibitor, the phosphoinositide
3-kinase inhibitor or the Akt inhibitor was tested. The bFGF treatment resulted in the
maintenance of the viability of canine BMSCs for 10 days, in the expression of neuronal
marker mRNAs and proteins and in the manifestation of neuron-like morphology. Furthermore,
in the bFGF-treated BMSCs, a high concentration of KCl and L-glutamate induced an increase
in intracellular Ca2+ levels. Each inhibitor significantly attenuated the
bFGF-induced increase in neuronal marker mRNA expression. These results suggest that bFGF
contributes to the differentiation of canine BMSCs into voltage- and glutamate-responsive
neuron-like cells and may lead to the development of new cell-based treatments for
neuronal diseases. 相似文献
49.
Kazuyuki SUZUKI Toshio SHIMAMORI Ayano SATO Kenji TSUKANO Masakazu TSUCHIYA Jeffrey LAKRITZ 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):977-979
The aim of the present study was to compare the ability of the commercially available portable test system (PTSTM) to detect endotoxin activity in bovine serum, with that of the traditional LAL-kinetic turbidimetric (KT) and chromogenic (KC) assays. Prior to testing, serum samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTSTM was not significantly different from that of the traditional LAL-based assays. The results using PTSTM correlated with those using KT (r2=0.963, P<0.001) or KC assays (r2=0.982, P<0.001). Based on these findings, the PTSTM could be applied as a simplified system to assess endotoxin activity in bovine serum. 相似文献