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201.
Pool‐based genome‐wide association study identified novel candidate regions on BTA9 and 14 for oleic acid percentage in Japanese Black cattle 下载免费PDF全文
Ayaka Nakajima Yuta Matsumoto Yoshinobu Uemoto Moriyuki Fukushima Emi Yoshida Eiji Iwamoto Takayuki Akiyama Namiko Kohama Eiji Kobayashi Takeshi Honda Kenji Oyama Hideyuki Mannen Shinji Sasazaki 《Animal Science Journal》2018,89(8):1060-1066
Fatty acid composition is an important indicator of beef quality. The objective of this study was to search the potential candidate region for fatty acid composition. We performed pool‐based genome‐wide association studies (GWAS) for oleic acid percentage (C18:1) in a Japanese Black cattle population from the Hyogo prefecture. GWAS analysis revealed two novel candidate regions on BTA9 and BTA14. The most significant single nucleotide polymorphisms (SNPs) in each region were genotyped in a population (n = 899) to verify their effect on C18:1. Statistical analysis revealed that both SNPs were significantly associated with C18:1 (p = .0080 and .0003), validating the quantitative trait loci (QTLs) detected in GWAS. We subsequently selected VNN1 and LYPLA1 genes as candidate genes from each region on BTA9 and BTA14, respectively. We sequenced full‐length coding sequence (CDS) of these genes in eight individuals and identified a nonsynonymous SNP T66M on VNN1 gene as a putative candidate polymorphism. The polymorphism was also significantly associated with C18:1, but the p value (p = .0162) was higher than the most significant SNP on BTA9, suggesting that it would not be responsible for the QTL. Although further investigation will be needed to determine the responsible gene and polymorphism, our findings would contribute to development of selective markers for fatty acid composition in the Japanese Black cattle of Hyogo. 相似文献
202.
Immune synergistic oligodeoxynucleotide from Lactobacillus rhamnosus GG enhances the immune response upon co‐stimulation by bacterial and fungal cell wall components 下载免费PDF全文
Shireen Nigar Yoshinari Yamamoto Takuma Okajima Takashi Sato Tasuku Ogita Takeshi Shimosato 《Animal Science Journal》2018,89(10):1504-1511
Bacterial genomic DNA has recently been shown to elicit a highly evolved immune defense. This response can be selectively triggered for a wide range of therapeutic applications, including use as a vaccine adjuvant to immunotherapies for allergy, cancer, and infectious diseases. Previously, we identified a low‐concentration immune synergistic oligodeoxynucleotide (iSN‐ODN, named iSN34) from Lactobacillus rhamnosus GG that has immunosynergistic activity upon costimulation of target cells with ligands of Toll‐like receptor 9 (TLR9). Here, we extend that observation by demonstrating the synergistic induction (in mouse splenocytes) of IL‐6 by the combination of iSN34 with cell wall components of bacteria and fungi. We observed that splenocytes pretreated with iSN34 and then costimulated with agonists for TLR1/2 (Pam3CSK4), TLR4 (lipopolysaccharide), or TLR2/6 (Zymosan) exhibited enhanced accumulation of IL‐6. These results suggested that the combination of iSN34 with TLR1/2, TLR4, or TLR2/6 agonists may permit the induction of a potent immune response. 相似文献
203.
Shin Kato Yoshitake Takada Satoshi Shimamura Kaori Hirata Takashi Sayama Fumio Taguchi-Shiobara Masao Ishimoto Akio Kikuchi Takeshi Nishio 《Breeding Science》2016,66(2):319-327
Resistance to soybean mosaic virus (SMV) is imperative for soybean (Glycine max (L.) Merr.) production in the Tohoku region. Molecular markers for SMV resistance were previously reported for U.S. SMV strains, but they cannot be applied because of the differences in strain classification between Japan and the U.S. A U.S. variety ‘Harosoy’ has been used mainly as a donor of resistance to SMV strains C and D in a Japanese breeding program, resulting in resistant varieties such as ‘Fukuibuki.’ Because ‘Harosoy’ harbors the Rsv3 gene conferring resistance to the virulent SMV strain groups, G5 through G7, it appears that the Rsv3 gene confers resistance to strains C and D. In this study, we introduced resistance to the two strains from ‘Fukuibuki’ into a leading variety ‘Ohsuzu’ by recurrent backcrossing with marker-assisted selection. All lines selected with markers near Rsv3 showed resistance to the strains, suggesting that the Rsv3 locus is responsible for the resistance. Three years of trials showed that one of the breeding lines, ‘Tohoku 169,’ was equivalent to ‘Ohsuzu’ with respect to agricultural characteristics such as seed size, maturity date, and seed yield, except for the SMV resistance. 相似文献
204.
Yoshiyuki Kiyono Yukihito Ochiai Yukihiro Chiba Hidetoshi Asai Kazuki Saito Tatsuhiko Shiraiwa Takeshi Horie Visone Songnoukhai Viengmany Navongxai Yoshio Inoue 《Journal of Forest Research》2007,12(5):371-383
In northern Lao People’s Democratic Republic, rising human population has drastically reduced the fallow period of slash-and-burn
agriculture which has led to a considerable decrease in the carbon stock in these communities. We estimated chronosequential
changes in the communities' carbon stocks, and established the relationship between the fallow period and fallow-period-average
carbon stocks in three carbon pools of bamboo-dominated communities in hilly areas of the Luang Prabang Province, northern
Lao People’s Democratic Republic. Based on measurements by destructive sampling, we devised a model and root-to-shoot ratios
for estimating bamboo biomass. In six secondary plant communities established after slash-and-burn cropping, we estimated
community biomass using the above model and others, and measured deadwood and litter stocks. The communities’ biomass and
deadwood significantly increased with time after the last cropping and the former reached about 100 Mg ha−1 after 15 years, whereas litter stocks did not show significant trends over time. Extending the fallow period from 2 to 5 years
would increase fallow-period-average carbon stock from 14.2 to 25.1 Mg C ha−1. The overstory height was significantly correlated with biomass, deadwood, and litter carbon stocks of these communities.
Based on our findings, changes in a community’s carbon stocks can be estimated using the changes in overstory height, which
should be taken into account in future studies to reduce uncertainty in estimating carbon stocks in tropical ecosystems. 相似文献
205.
Motoshi Hiratsuka Takeshi Toma Nina Mindawati Ika Heriansyah Yasushi Morikawa 《Journal of Forest Research》2005,10(6):487-491
Biomass of a mature man-made forest in West Java, Indonesia, was estimated to evaluate the carbon sequestration potential
of plantation forest in the humid tropics. Twenty plots, each 0.25 ha in area and containing one to six planted species over
40 years of age and with closed canopies, were selected. Trunk dry mass was estimated from trunk diameter, tree height, and
bulk density. Maximum trunk diameter (122 cm) was observed in a 46-year-old Khaya grandifoliola C. DC. tree, and the tallest tree (51 m) was a 46-year-old Shorea selanica (DC.) Blume. The largest trunk biomass (911 Mg ha−1) was achieved in the plot composed of two Khaya spp. Among the plots composed of indigeneous Dipterocarpaceae species, the largest trunk biomass was 635 Mg ha−1. These trunk biomasses were larger than those reported from primary rainforests in Southeast Asia (e.g., 403 Mg ha−1 in East Kalimantan, 522 and 368 Mg ha−1 in Peninsular Malaysia). The large biomass in this forest suggests that, given favorable conditions, man-made forests can
accumulate the quantities of atmospheric carbon that were lost by the logging of primary forests in the humid tropics. 相似文献
206.
Variations in the compositions of low-boilingpoint (LBP) monoterpenes in needle samples of 50 hinoki (Chamaecyparis obtusa) trees were investigated using the headspace technique. Considerable compositional variations were revealed, especially in sabinene composition. The sabinene composition varied from 4.9% to 78.0% of the total LBP monoterpenes.-Pinene, myrcene, and limonene also showed considerable variations (9.0%–32.7%, 5.5%–22.6%, 3.6%–29.0% respectively). Analysis of the monoterpene composition allowed definition of four chemotypes based on the contingency table test. No correlation was observed between tree size and LBP monoterpene composition, indicating that the compositional variation in LBP monoterpene exists genetically in this population of hinoki.Part of this paper was presented at the 11th annual meeting of the Chugoku Shikoku branch of the Japan Wood Research Society, Matsue, September 1999 相似文献
207.
The conditions for the extraction of phytosterol from masson pine raw tall oil were studied by experimenting with the procedural steps that included saponification, extraction, crystallization, and recrystallization. The influences of alkali dosage, saponifying temperature, saponifying time, and variety and dosage of extracting agent on the yield of unsaponifiables were investigated. The effects of various solvents used for removing residual soap from unsaponifiables and the effects of crystallization temperature, time, and solvent on the yield and composition of crystal in the processes of crystallization and recrystallization were examined to determine suitable technical conditions. The phytosterol obtained using optimal conditions contained 92% -sitosterol and 8% campesterol. Its melting point and yield were 135.7°–136.8°C and 0.54% (based on the weight of crude tall oil), respectively. 相似文献
208.
Shuzo?SueyoshiEmail author Yoshifumi?Miyazaki Takeshi?Morikawa 《Journal of Wood Science》2004,50(6):494-497
We investigated the physiological and psychological responses of nine normal men to the prolonged light floor-impact sounds of 60dBA and 80dBA generated by a tapping machine in a two-story wooden house. Blood pressure was measured, and a sensory evaluation was also conducted using the semantic differential method. The results obtained were as follows: (1) the increase in systolic blood pressure immediately after exposure to the light floor-impact sounds depended on the level of the sounds, (2) the variations in feelings due to the prolonged light floor-impact sounds were identified by factor analysis, and (3) the subjects showed no difference in comfortable feeling for the prolonged light floor-impact sounds of 60dBA and 80dBA, but differences in the variation of the systolic blood pressure were detected.Part of this research was presented at the 47th Annual Meeting of the Japan Wood Research Society, Kochi, April 1997 相似文献
209.
We tested the hypothesis that, in tropical pioneer tree species, vertical leaf angle contributes to high carbon gain because it minimizes damage caused by high irradiances. Diurnal changes in leaf gas exchange and chlorophyll fluorescence were measured in east-facing (EL), west-facing (WL) leaves, and in leaves artificially held horizontal (HL) in the uppermost canopy of Macaranga conifera (Zoll.) Muell. Arg. Maximum values of net photosynthetic rate (P(n)) for EL and HL reached 12 &mgr;mol m(-2) s(-1), whereas maximum P(n) for WL was only 6 &mgr;mol m(-2) s(-1). Midday depressions of P(n) and stomatal conductance occurred at high photosynthetic photon flux densities (PPFD), especially for HL. Photosystem II quantum yield (DeltaF/F(m)') of HL for a given PPFD at the leaf surface was lower in the afternoon than in the morning. Values of DeltaF/F(m)' for HL measured at dusk were lower than those measured just before dawn, suggesting that HL suffered from high light and heat load. Variations in the morphology and physiology of the canopy leaves were associated with different light environments, and there was circumstantial evidence of a transitional point at a PPFD of about 20-30% of full sunlight. Maximum P(n) and nitrogen (N) content were higher in upper canopy leaves than in lower canopy leaves, and the differences were mainly associated with differences in lamina thickness. We conclude that the vertical leaf angle and thick lamina of the top canopy leaves contributed to enhance total carbon gain of the whole plant. 相似文献
210.
Studies on the synthesis and properties of terpene-phenol-aldehyde resin with a high softening point
Synthesis conditions of terpene-phenol-aldehyde resin with a high softening point were studied based on the reactions among-pinene, phenol, and formaldehyde. A suitable catalyst system and the best processing conditions were obtained by laboratory experiments. The influence of the raw materials ratios, reaction temperature, reaction time, and catalyst dose on the softening point, yield, and color of the synthesized resin was examined. The physical and chemical characteristics of the resin were determined: softening point 140°C (ball and ring method); color value 7 (Gardner); acid value (KOH mg/g) <1; bromine value (Br2 mg/100g) <64; saponification value (KOH mg/g) <1; average molecular weight 830. The yield of resin was more than 85% (based on the total raw material). 相似文献