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981.
This study investigated the behavior of piezoelectric, dielectric, and elastic constants and the crystallinity in wood cellulose by repeated measurements (n = 42) between 100°C and 220°C. There was an insignificant change in the piezoelectric constant during repeated measurements in this temperature range. On the other hand, thermal decomposition of the amorphous region contributed to the decreasing trend of dielectric and elastic constants, although only a small increase in the elastic constant was found at the time of the initial measurements. The increase in the repeated measurements in this temperature range resulted in an increase in the piezoelectric loss modulus constantd
25, which is closely related to energy loss. Thed
25 peak shifted to a higher temperature with increasing measurements, which might be due not to the increase in rigidity of the wood specimen but to the increase in total peak area, which was observed during the later measurements. At the same time, variations of piezoelectric loss modulusd
25 ande
25 at advanced stages of the measurements suggested damage and structural changes in the wood. 相似文献
982.
Vegetation cover types on Changbai Mountain, a natural biosphere reserve (2,000 km2) in northeast China, were derived by using multisensor satellite imagery fused with Landsat TM and SPOT HRV-XS. DEM data
were used for improving classification accuracy. Cover types were classified into 20 groups. Bands 4 and 5 of Landsat TM image
acquired on July 18, 1997, and band 1 of SPOT HRV-XS image acquired on Oct. 19, 1992, were fused to a false color image, and
maximum likelihood supervised classification was performed. Data fusion showed high accuracy of identification, compared to
individual images. The overall accuracy of classification of individual images by SPOT HRV-XS reached 56%, and TM 66%, while
the fused data set provided accuracy of about 78%, which was raised to 81% after recoding by using DEM. There were five vegetation
zones on the mountain, from the base to the peak: hardwood forest zone, mixed forest zone, conifer forest zone, birch forest
zone, and tundra zone. Spruce-fir dominated conifer forest was the most prevalent (nearly 50%) vegetation type, followed by
Korean pine and mixed forest (17%) and larch forest (5%). HRV image taken in leaf-off season is useful for discriminating
forest from non-forest, and evergreen forest from hardwood forest, while the summer image (TM) provides detailed information
on the difference in similar vegetation types, like hardwood forest with different compositions. 相似文献
983.
Takuyuki Yoshioka Kazuhiro Aruga Hideo Sakai Hiroshi Kobayashi Toshio Nitami 《Journal of Forest Research》2002,7(3):157-163
The purpose of this study is to examine the feasibility of a system to harvest logging residues (or slashes) as a new resource
for energy in Japan. A harvesting and transporting system for residual forest biomass was constructed with reference to some
European countries where the utilization of bioenergy is making steady progress and examined on the basis of field experiments
in Japanese forestry. The feasibility of the system is discussed from the standpoints of cost and energy, and the system is
compared with those of the European countries. With respect to the system proposed in this study, it is desirable that the
process of chipper comminuting is incorporated into the system as early as possible, considering the trends of harvesting
cost and fuel consumption per unit weight of residual forest biomass. Such a system is not particularly feasible in Japan
from the standpoint of the harvesting cost per MWh of bioenergy. However, no specific problems are found from the point of
view of the energy input rate, and it is clarified that it is possible for Japan to reduce domestic carbon dioxide emissions
by utilizing biomass as an energy resource. A comparison with the European countries and a preliminary sensitivity analysis
of the system demonstrate that the technical development to reduce the harvesting cost,e.g., improving the forwarding and transporting efficiency, and support from the government are essential for realizing bioenergy
utilization in Japan.
A part of this paper was orally presented at the 111th Annual Meeting of the Japanese Forestry Society (2000).
JSPS Research Fellow.
This study was supported in part by a Grant-in-Aid for Scientific Research from the Japan Ministry of Education, Science and
Culture (No. 10460061). 相似文献
984.
Yuki Monden Takuya Hara Yoshihiro Okada Osamu Jahana Akira Kobayashi Hiroaki Tabuchi Shoko Onaga Makoto Tahara 《Breeding Science》2015,65(2):145-153
Sweetpotato (Ipomoea batatas L.) is an outcrossing hexaploid species with a large number of chromosomes (2n = 6x = 90). Although sweetpotato is one of the world’s most important crops, genetic analysis of the species has been hindered by its genetic complexity combined with the lack of a whole genome sequence. In the present study, we constructed a genetic linkage map based on retrotransposon insertion polymorphisms using a mapping population derived from a cross between ‘Purple Sweet Lord’ (PSL) and ‘90IDN-47’ cultivars. High-throughput sequencing and subsequent data analyses identified many Rtsp-1 retrotransposon insertion sites, and their allele dosages (simplex, duplex, triplex, or double-simplex) were determined based on segregation ratios in the mapping population. Using a pseudo-testcross strategy, 43 and 47 linkage groups were generated for PSL and 90IDN-47, respectively. Interestingly, most of these insertions (~90%) were present in a simplex manner, indicating their utility for linkage map construction in polyploid species. Additionally, our approach led to savings of time and labor for genotyping. Although the number of markers herein was insufficient for map-based cloning, our trial analysis exhibited the utility of retrotransposon-based markers for linkage map construction in sweetpotato. 相似文献
985.
Yamada O Kobayashi M Sugisaki O Ishii N Ito K Kuroki S Sasaki Y Isotani M Ono K Washizu T Bonkobara M 《Veterinary immunology and immunopathology》2011,142(1-2):101-106
Target therapy using the tyrosine kinase inhibitor imatinib is one of the new therapeutic approaches for canine mast cell tumors (MCTs). In the present report, we demonstrate a clinical response to imatinib in a dog with MCT carrying a c-kit c.1523A>T mutation. Moreover, the effect of this mutation on the phosphorylation status of KIT and the inhibitory potency of imatinib on the phosphorylation of the mutant KIT were examined in vitro. A dog with a MCT tumor mass on the right forelimb sole with lymph node metastasis and mastocytemia was treated with imatinib. The MCT mass markedly shrank and mastocytemia became undetectable with 2 weeks of treatment. The lymph node enlarged by metastasis became normal in size with 5 weeks of treatment. From the sequencing analysis of c-kit in tumor cells, a substitution mutation c.1523A>T that alters the amino acid composition (p.Asn508Ile) within the extracellular domain of KIT was identified. The mutant KIT expressed on 293 cells showed ligand-independent phosphorylation and imatinib suppressed this phosphorylation in a dose-dependent manner. From these findings, imatinib was considered to elicit a clinical response in a canine case of MCT via inhibition of the constitutively activated KIT caused by a c-kit c.1523A>T mutation. 相似文献
986.
987.
Effect of trehalose coating on basic fibroblast growth factor release from tailor-made bone implants
Choi S Lee J Igawa K Suzuki S Mochizuki M Nishimura R Chung UI Sasaki N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(12):1547-1552
Artificial bone implants are often incorporated with osteoinductive factors to facilitate early bone regeneration. Calcium phosphate, the main component in artificial bone implants, strongly binds these factors, and in a few cases, the incorporated proteins are not released from the implant under conditions of physiological pH, thereby leading to reduction in their osteoinductivity. In this study, we coated tailor-made bone implants with trehalose to facilitate the release of basic fibroblast growth factor (bFGF). In an in vitro study, mouse osteoblastic cells were separately cultured for 48 hr in a medium with a untreated implant (T-), trehalose-coated implant (T+), bFGF-incorporated implant (FT-), and bFGF-incorporated implant with trehalose coating (FT+). In the FT+ group, cell viability was significantly higher than that in the other groups (P<0.05). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that trehalose effectively covered the surface of the artificial bone implant without affecting the crystallinity or the mechanical strength of the artificial bone implant. These results suggest that coating artificial bone implants with trehalose could limit the binding of bFGF to calcium phosphate. 相似文献
988.
Wang M Mominoki K Kinutani M Wang Z Kobayashi N Shimokawa T Nabeka H Fujiwara T Matsuda S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):447-452
Spina bifida aperta (SBA) is a congenital malformation of the spinal cord with complications such as spinal ataxia and bowel and bladder dysfunction. We have developed a chick model with surgery-induced SBA that shows spinal ataxia after hatching. In the present study, motor neurons in the early stages in chicks with and without SBA were observed by immunohistochemical staining with a monoclonal antibody against Islet-1, a motor neuron marker. Delay in migration and maturation of motor neurons was observed in SBA. Although the final numbers of Islet-1-positive neurons in these two groups were not different, a defect in the production and elimination of excess motor neurons in the early developmental stages in the SBA group may be involved in the pathological mechanism of the motor complications of this disease. 相似文献
989.
Inaba Y Aikawa Y Hirai T Hashiyada Y Yamanouchi T Misumi K Ohtake M Somfai T Kobayashi S Saito N Matoba S Konishi K Imai K 《The Journal of reproduction and development》2011,57(4):437-443
The aim of this study was to develop an in-straw dilution method suitable for 1-step bovine embryo transfer of vitrified embryos using the Cryotop vitrification-straw dilution (CVSD) method. The development of embryos vitrified using the CVSD method was compared with those of embryos cryopreserved using in-straw vitrification-dilution (ISVD) and conventional slow freezing, outside dilution of straw (SFODS) methods. In Experiment 1, in vitro-produced (IVP) embryos cryopreserved using the CVSD method were diluted, warmed and exposed to the dilution solution at various times. When vitrified IVP embryos were exposed to the dilution solution for 30 min after warming, the rates of embryos developing to the hatched blastocyst stage after 72 h of culture (62.0-72.5%) were significantly lower (P<0.05) than those of embryos exposed to the solution for 5 and 10 min (82.4-94.3%), irrespective of supplementation with 0.3 M sucrose in the dilution solution. In Experiment 2, the rate of embryos developing to the hatching blastocyst stage after 48 h of culture in IVP embryos cryopreserved using the SFODS method (75.0%) was significantly (P<0.05) lower than those of embryos cryopreserved using the CVSD and ISVD methods (93.2 and 97.3%, respectively). In Experiment 3, when in vivo-produced embryos that had been cryopreserved using the CVSD, ISVD and SFODS methods and fresh embryos were transferred to recipient animals, no significant differences were observed in the conception and delivery rates among groups. In Experiment 4, when IVP embryos derived from oocytes collected by ovum pick-up that had been cryopreserved using the CVSD and ISVD methods and fresh embryos were transferred to recipient animals, no significant differences were observed in the conception rates among groups. Our results indicate that this simplified regimen of warming and diluting Cryotop-vitrified embryos may enable 1-step bovine embryo transfer without the requirement of a microscope or other laboratory equipment. 相似文献
990.
Kobayashi S Murakami K Sasaki S Okubo H Hirota N Notsu A Fukui M Date C 《Public health nutrition》2011,14(7):1200-1211