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121.
Characterization of Treatment Processes and Mechanisms of COD, Phosphorus and Nitrogen Removal in a Multi-Soil-Layering System 总被引:3,自引:0,他引:3
Kuniaki Sato Tsugiyuki Masunaga Toshiyuki Wakatsuki 《Soil Science and Plant Nutrition》2005,51(2):213-221
Characteristics of the treatment processes inside a MSL system were investigated by using a laboratory-scale MSL system, which was set up in a D 10 × W 50 × H 73 cm acrylic box enclosing "soil mixture blocks" alternating with permeable zeolite layers. For the study of the treatment processes inside the system, wastewater, with mean concentrations (mg L−1 ) of COD: 70, T-N: 12, T-P: 0.9, was introduced into the system at a loading rate of 1,000 L m−2 d−1 . Treatment processes in the MSL system were different for the COD, P and N pollutants. Eighty percent of COD was removed in the 1st soil layer among the 6 layers, and the removal rate increased as water moved down and finally reached 90% in the last layer of the system. Phosphorus concentration was lower under the soil mixture layers than under the permeable layers, presumably because P was adsorbed mainly by soil and mixed iron particles. The P concentration in water gradually decreased in the lower layers of the system. The concentration of PO4 3- -P was generally lower in the aerated MSL system than in the non-aerated one. NH4 + -N was adsorbed and nitrified in the upper part of the system. The NO3 − -N concentration was lower in water under the soil mixture layers than under the permeable layers, indicating that denitrification mainly occurred in the soil mixture layers. 相似文献
122.
Phenotypic and functional analysis of bovine peripheral blood dendritic cells before parturition by a novel purification method 下载免费PDF全文
Tao Zhuang Megumi Urakawa Hidetoshi Sato Yuko Sato Teruaki Taguchi Tsuyoshi Umino Shiro Katto Koutaro Tanaka Kozue Yoshimura Naokazu Takada Hiroko Kobayashi Megumi Ito Michael T. Rose Yoshio Kiku Yuya Nagasawa Haruki Kitazawa Kouichi Watanabe Tomonori Nochi Tomohito Hayashi Hisashi Aso 《Animal Science Journal》2018,89(7):1011-1019
Dendritic cells (DCs) are specialized antigen presenting cells specializing in antigen uptake and processing, and play an important role in the innate and adaptive immune response. A subset of bovine peripheral blood DCs was identified as CD172a+/CD11c+/MHC (major histocompatibility complex) class II+ cells. Although DCs are identified at 0.1%–0.7% of peripheral blood mononuclear cells (PBMC), the phenotype and function of DCs remain poorly understood with regard to maintaining tolerance during the pregnancy. All cattle used in this study were 1 month before parturition. We have established a novel method for the purification of DCs from PBMC using magnetic‐activated cell sorting, and purified the CD172a+/CD11c+ DCs, with high expression of MHC class II and CD40, at 84.8% purity. There were individual differences in the expressions of CD205 and co‐stimulatory molecules CD80 and CD86 on DCs. There were positive correlations between expression of cytokine and co‐stimulatory molecules in DCs, and the DCs maintained their immune tolerance, evidenced by their low expressions of the co‐stimulatory molecules and cytokine production. These results suggest that before parturition a half of DCs may be immature and tend to maintain tolerance based on the low cytokine production, and the other DCs with high co‐stimulatory molecules may already have the ability of modulating the T‐cell linage. 相似文献
123.
Akira Shigematsu Nobuya Mizoue Kumiko Ide Kakada Khun Muthavy Pheng Shigejiro Yoshida Katsuhisa Kohroki Noriko Sato 《New Forests》2011,42(2):149-162
We estimated the production of rubberwood from 1996 to 2011 in Cambodia. We employed data from interview surveys with three
rubberwood processing companies and statistics from estate rubber plantations and wood retailing companies. The result was
that the end use of rubberwood in Cambodia was the sawntimber products, being exported to Vietnam and China. The yield rate
from rubberwood stumpage into sawn timber was between 11.6 and 14.9%, closely matching the rates of Malaysia and Thailand.
The average production of rubberwood roundwood from 1996 to 2011 was 254,697 m3/year, of which sawn timber as well as residuals in secondary processing was 84,559 and 170,138 m3/year, respectively. Although the timber production of Cambodia has declined sharply due to the strict restriction of natural
forest logging, rubberwood could explain more than 60% of the domestic industrial roundwood production from 2000. We suggest
the necessity of monitoring the expansion of rubber plantations in new rubber producing countries and linking the rubberwood
production with the regional wood resource management. 相似文献
124.
D.?H.?Xu S.?Wahyuni Y.?Sato M.?Yamaguchi H.?Tsunematsu T.?BanEmail author 《Genetic Resources and Crop Evolution》2006,53(5):883-889
To evaluate the genetic diversity and to clarify the genetic relationships of Japanese peach cultivars, we analyzed the amplified
fragment length polymorphism (AFLP) and traced the pedigree of 17 Japanese commercial peach cultivars and six traditional
accessions. Sixteen AFLP primer combinations produced a total of 837 fragments and 146 polymorphic bands with a polymorphism
percentage of 17.5%. All of the peach accessions could be identified from differences in at least 10 polymorphic bands. A
cluster analysis showed that all the Japanese commercial peach cultivars, except ‘Kiyomi’ and ‘Jichigetsuto’, formed a major
group consisting of three sub-groups. Of the six traditional accessions, four were genetically distant from the Japanese commercial
peach cultivars while two accessions from China were classified into the Japanese commercial peach cultivars group. Both the
AFLP analysis and pedigree tracing suggested that Japanese commercial peach cultivars are mainly derived from ‘Shanhai Suimitsuto’,
one of the traditional accessions from China. Although the genetic relationships revealed by AFLP were generally in agreement
with those shown by the pedigree information, some contradictions were found. Combining the AFLP results and pedigree information
can provide a better understanding of the genetic relationships of Japanese peach cultivars. 相似文献
125.
Mishra B Kizaki K Koshi K Ushizawa K Takahashi T Hosoe M Sato T Ito A Hashizume K 《Domestic animal endocrinology》2012,42(2):63-73
Extracellular matrix metalloproteinase inducer (EMMPRIN) and its induced matrix metalloproteinases (MMPs) play a crucial role in tissue remodeling during the peri-implantation period. However, the role of EMMPRIN in the bovine placenta is still unclear. We have postulated that EMMPRIN might play a regulatory role in trophoblastic cell functions during gestation by itself or through the regulation of MMP expression. In this study, EMMPRIN mRNA was detected in the bovine placentome and interplacentome throughout gestation, and its expression was significantly higher in the cotyledon during late gestation. In situ hybridization showed that EMMPRIN mRNA was expressed in the caruncular epithelium and the cotyledonary epithelium, including binucleate cells. Western blot analysis detected a band representing a protein of approximately 65 kDa in the caruncular and cotyledonary tissues, and the intensity of its expression was increased in both of these tissues during late gestation. The expression levels of MMP-2 and MMP-14 in the bovine placenta were higher during late gestation, as was observed for EMMPRIN. Therefore, EMMPRIN might regulate trophoblastic cell functions, especially those of binucleate cells, through MMP expression in the bovine placenta. 相似文献
126.
Nakamura Y Yoshimoto M Murata Y Shimoishi Y Asai Y Park EY Sato K Nakamura Y 《Journal of agricultural and food chemistry》2007,55(11):4407-4413
In the present study, papaya (Carica papaya) seed and edible pulp were carefully separated and then the contents of benzyl isothiocyanate and the corresponding glucosinolate (benzyl glucosinolate, glucotropaeolin) quantified in each part. The papaya seed with myrosinase inactivation contained >1 mmol of benzyl glucosinolate in 100 g of fresh seed. This content is equivalent to that of Karami daikon (the hottest Japanese white radish) or that of cress. The papaya seed extract also showed a very high activity of myrosinase and, without myrosinase inactivation, produced 460 micromol of benzyl isothiocyanate in 100 g of seed. In contrast, papaya pulp contained an undetectable amount of benzyl glucosinolate and showed no significant myrosinase activity. The n-hexane extract of the papaya seed homogenate was highly effective in inhibiting superoxide generation and apoptosis induction in HL-60 cells, the activities of which are comparable to those of authentic benzyl isothiocyanate. 相似文献
127.
R. Ishikawa S. Yamanaka Y. Fukuta S. Chitrakon C. Bounphanousay K. Kanyavong L.-H. Tang I. Nakamura T. Sato Y.-I. Sato 《Genetic Resources and Crop Evolution》2006,53(2):245-252
The purpose of this study was to assess the extent of genetic erosion of traditional upland germplasm in northern Thailand
as a result of gene-flow from distinct strains carrying different genotypes. Even modern variety specific markers have not
been developed, there is a comparative population in Laos. Thus, both populations were compared with various characters to
evaluate gene-flow from modern variety to landraces. Glutinous and glabrous strains are predominated in Laos. However, such
strains were drastically decreased in north–east Thailand. Gene diversity is higher in Thailand, compared to Laos at seven
isozyme loci. This was a result of the higher frequencies of Indica strains and heterozygotes in Thailand. Plastid type was
also determined by using an INDEL marker. Nearly half of Indica strains carried the Japonica plastid. Heterozygotes also tended
to carry Japonica cytoplasm. Such nuclear–cytoplasm substituted strains and heterozygotes were probably generated by natural
hybridization. Japonica strains tended to be a maternal donor rather than Indica ones. Or Indica strains would easily release
pollens, which grow outside of upland fields. 相似文献
128.
Tetsuya Suzuki Jun Itakura Masumi Watanabe Mari Ohta Yuri Sato Yuko Yamaya 《Journal of agricultural and food chemistry》2002,50(1):230-234
Electrolyzed anodic NaCl solutions [EW+], prepared by the electrolysis of 0.1% NaCl, have been shown to instantly inactivate most pathogens that cause food-borne disease. Elimination of food-borne pathogens does not necessarily guarantee food safety because enterotoxins produced by pathogens may remain active. We have tested whether EW+ can inactivate Staphylococcal enterotoxin A (SEA), one of the major enterotoxins responsible for food poisoning. Fixed quantities of SEA were mixed with increasing molar ratios of EW+, and SEA was evaluated by reversed-phase passive latex agglutination (RPLA) test, immunoassay, native polyacrylamide gel electrophoresis (PAGE), and amino acid analysis after 30 min incubations. Exposure of 70 ng, or 2.6 pmol, of SEA in 25 microL of PBS to a 10-fold volume of EW+, or ca. 64.6 x 10(3)-fold molar excess of HOCl in EW+, caused a loss of immuno-reactivity between SEA and a specific anti-SEA antibody. Native PAGE indicated that EW+ caused fragmentation of SEA, and amino acid analysis indicated a loss in amino acid content, in particular Met, Tyr, Ile, Asn, and Asp. Staphylococcal enterotoxin-A excreted into culture broth was also inactivated by exposure to an excess molar ratio of EW+. Thus, EW+ may be a useful management tool to ensure food hygiene by food processing industries. 相似文献
129.
Hisashi Sato Akihiko Ito Akinori Ito Takashi Ise Etsushi Kato 《Soil Science and Plant Nutrition》2013,59(1):34-47
Although climate conditions primarily determine the distribution and functioning of vegetation, vegetation also influences climate via biophysical and biogeochemical features such as evapotranspiration, albedo, carbon cycling, trace gas emissions and the roughness of the land surface. Forecasts of rapid climate change during the next 100~200 years, fueled by an increase in greenhouse gases, have motivated the development of land surface models (LSMs) that predict changes in vegetation functions. Here, we review how these models have been developed and used to simulate interactive processes between climate and the land surface. Current limitations and future perspectives of the LSMs are also presented. 相似文献
130.
Iwai K Hasegawa T Taguchi Y Morimatsu F Sato K Nakamura Y Higashi A Kido Y Nakabo Y Ohtsuki K 《Journal of agricultural and food chemistry》2005,53(16):6531-6536
In the present study, we identified several food-derived collagen peptides in human blood after oral ingestion of some gelatin hydrolysates. Healthy human volunteers ingested the gelatin hydrolysates (9.4-23 g) from porcine skin, chicken feet, and cartilage after 12 h of fasting. Negligible amounts of the peptide form of hydroxyproline (Hyp) were observed in human blood before the ingestion. After the oral ingestion, the peptide form of Hyp significantly increased and reached a maximum level (20-60 nmol/mL of plasma) after 1-2 h and then decreased to half of the maximum level at 4 h after the ingestion. Major constituents of food-derived collagen peptides in human serum and plasma were identified as Pro-Hyp. In addition, small but significant amounts of Ala-Hyp, Ala-Hyp-Gly, Pro-Hyp-Gly, Leu-Hyp, Ile-Hyp, and Phe-Hyp were contained. 相似文献