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81.
Saito T Furuta T Hwang JH Kuramoto S Nishino K Suzuki N Chen R Yamada A Ito K Seno Y Nonaka T Ikehata H Nagasako N Iwamoto C Ikuhara Y Sakuma T 《Science (New York, N.Y.)》2003,300(5618):464-467
We describe a group of alloys that exhibit "super" properties, such as ultralow elastic modulus, ultrahigh strength, super elasticity, and super plasticity, at room temperature and that show Elinvar and Invar behavior. These "super" properties are attributable to a dislocation-free plastic deformation mechanism. In cold-worked alloys, this mechanism forms elastic strain fields of hierarchical structure that range in size from the nanometer scale to several tens of micrometers. The resultant elastic strain energy leads to a number of enhanced material properties. 相似文献
82.
Individuals of four species of Leporinus were captured in the floodplain of the Upper Paraná River and their metazoan parasites were collected. Fifty-eight taxa of ectoparasites and endoparasites were recorded: 31 in Leporinus lacustris, 32 in Leporinus friderici, 28 in Leporinus obtusidens and 25 in Leporinus elongatus. The aim of this paper was to study the relationship between the host's condition and the parameters of infrapopulations and infracommunities. The health of the host was represented by the relative condition factor (Kn). Richness and number of individuals in the infracommunities of ectoparasites covariated with the Kn of the hosts in one species of fish. Some infrapopulations of ectoparasites covariated negatively and/or the mean Kn of parasitized individuals was lower than those without parasites. The abundance in some infrapopulations of endoparasites covariated positively with the Kn and/or the mean Kn of parasitized fish was better. These results may be related to different transmission strategies used by ecto and endoparasites. 相似文献
83.
Jinu Eo Shuhei Takemoto Kazunori Otobe 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(2):231-237
We investigated if rates of propagation and migration were related with the level of virulence in the pinewood nematode Bursaphelenchus xylophilus using 17 offspring lines from the F2 crosses between virulent and avirulent isolates. Virulence was tested by inoculating seedlings of Pinus thunbergii with the nematodes. The proportion of dead seedlings ranged from 13.3% to 77.8%, 20 weeks after inoculation. Migration rate
of the nematodes was estimated by measuring their migration distance per unit time in an artificial substrate that imitated
pathways in pine trees. Migration rate varied from 0.85 to 3.53 mm min−1. Propagation rate was determined based on population growth on the fungus Botrytis cinerea, and it ranged between 103.88 and 104.99 per 12 days. Statistical analyses revealed that virulence was not correlated with migration rate, but was negatively correlated
with propagation rate on Botrytis cinerea, suggesting that the nematodes paid some cost for virulence. Also, there was no relationship between rates of migration and
propagation. Cluster analysis showed that the biological parameters varied between crossbred lines, with no kinship bias,
suggesting the absence of sex-linked inheritance in virulence and rates of propagation and migration. 相似文献
84.
Eustoma grandiflorum is one of the leading cut‐flowers in Japan. There are market demands for cultivars with deep‐yellow flowers, but they have never been bred successfully. By investigating the carotenoid accumulation and carotenogenic gene expressions, this study attempted to explore the reasons that block the formation of deep‐yellow colour in Eustoma. High performance liquid chromatography analysis showed that the carotenoid compositions in petals were similar to those in leaves, accumulating mainly lutein, violaxanthin and β‐carotene. The total carotenoid contents decreased as the petals matured in all the cultivars tested. Quantitative real‐time PCR analysis showed that the expression levels of PSY, LCYB, ZDS and LCYE showed significant differences between white and pale‐yellow petals or between petals and leaves, indicating that these enzymes may play a key role in the carotenoid biosynthesis in E. grandiflorum. The expression levels of CCD4 were high in both pale‐yellow and white petals during development, suggesting that carotenoid degradation activity is high in the petals. We then conclude that the total carotenoid accumulation level could be determined by the balance between carotenoid biosynthesis and degradation activities. 相似文献
85.
为筛选羊尤氏泰勒虫裂殖子功能基因,用羊尤氏泰勒虫裂殖子提取物免疫BALB/c小鼠,将小鼠脾脏细胞与鼠骨髓瘤SP2/0-Ag14细胞融合,融合细胞培养上清用酶联免疫吸附法和免疫印记法检测。提取羊尤氏泰勒虫裂殖子mRNA后,进行cDNA合成与文库构建。文库在免疫学噬斑筛选后,将阳性克隆进行测序和序列BLAST搜索。筛选结果显示有两个阳性克隆。所得序列BLAST搜索结果显示,它与12类寄生虫新生多态相关复合物α多肽基因的同源性在39%到78%之间。结果提示,所筛选的序列为羊尤氏泰勒虫裂殖子新生多态相关复合物α多肽基因不完全序列。该研究为今后使用单克隆抗体筛选羊泰勒虫功能性基因提供了参考。 相似文献
86.
The complete nucleotide sequence of the mitochondrial genome of long-finned squid Loligo edulis forma kensaki (L. edulis f. kensaki, Teuthida: Myopsida) was determined. It contains 13 protein-coding genes, 12SrRNA, 16SrRNA, and the 22 tRNA genes, and three long noncoding regions. We also determined the mitochondrial genome nucleotide sequence of seasonal brood samples of L. edulis f. budo collected from the western part of the Sea of Japan in the autumn to winter seasons, which showed morphologic discrepancies with L. edulis f. kensaki. Comparison of the two complete sets of mitochondrial DNA data showed that the similarity of the two sequences was as high as 99.9?%, with only eight nucleotide substitutions in coding regions. The complete mitochondrial genome of Loligo edulis f. kensaki from Nagasaki Pref. is 17360?bp and L. edulis f. budo from the Shimane Pref. is 17351?bp. The nucleotide sequences and haplotype patterns in ND1 suggest that L. edulis f. kensaki and L. edulis f. budo share a single genetic background. 相似文献
87.
Yoko Yamashita Toru Takeuchi Masataka Okuyama Jun Sasaki Kakumasa Onodera Mikako Sato Chihiro Souma Shigehiko Ebe 《Breeding Science》2014,64(4):404-408
The yellowing strain of Soybean dwarf virus (SbDV-YS) causes yellowing and yield loss in common bean (Phaseolus vulgaris). The most effective control is achieved through breeding for resistance. An indeterminate climbing cultivar with a white seed coat, ‘Oofuku’, is resistant to SbDV-YS in inoculation tests. We crossed ‘Oofuku’ with an elite cultivar, ‘Taisho-Kintoki’, which is SbDV-YS-susceptible, determinate dwarf with a red-purple seed coat, and performed amplified-fragment-length polymorphism analysis of F3 lines. From nucleotide sequences of the resistant-specific fragments and their flanking regions, we developed five DNA markers, of which DV86, DV386, and DV398 were closely linked to Sdvy-1, a resistance gene. Using the markers, we developed ‘Toiku-B79’ and ‘Toiku-B80’, the near-isogenic lines (NILs) incorporating Sdvy-1 in the background of ‘Taisho-Kintoki’. The NILs had similar growth habit, maturity date and seed shape to those of ‘Taisho-Kintoki’. The quality of boiled beans was also similar, except that the NILs had more seed coat cracking than ‘Taisho-Kintoki’. The NILs showed no SbDV-YS infection in inoculation tests. We suggest that Sdvy-1 is a useful source of SbDV-YS resistance in common bean. 相似文献
88.
To clarify the socioeconomic factors influencing global paper and paperboard demand, a panel data analysis was conducted covering the period 1961–2014. This study used paper and paperboard demand as the dependent variable, and a country’s economic level, Internet usage rate, plastic packaging demand, and time trend as the explanatory variables. An inverse U-shaped quadratic relationship, such as an environmental Kuznets curve, was found between economic level and paper and paperboard demand, which saturates and begins to decline as economic level increases. The economic level representing the turning point differs significantly with the use, ranging from around 37,000 US$/person for newsprint paper to around 66,000 US$/person for printing and writing paper. For both newsprint paper and printing and writing paper, demand declines owing to the spread of the Internet as the economic level rises, although this reductive effect is greater for printing and writing paper than for newsprint paper. A substitution relationship is not found between wrapping paper and corrugated cardboard on the one hand and plastic packaging on the other hand as the economic level becomes higher. 相似文献
89.
Yasumasa Ogawa Kento Sakakibara Tsugumi Seki Chihiro Inoue 《Water, air, and soil pollution》2018,229(11):359
We previously reported that a simple treatment—addition of only small amounts of water to coal fly ash (CFA) to form CFA paste followed by aging for 1–4 weeks—is advantageous for the immobilization of highly soluble B, F, Cr, and As. In this study, we investigated the leachability of Ca, SO4, B, and As over time from non-aged and aged CFA samples to elucidate a possible immobilization mechanism. For this purpose, two types of CFA samples, one showing effective immobilization of B and As by water addition and aging (sample A) and the other showing less or no immobilization (sample B), were examined. Calcium and SO4, B, and As in non-aged sample A dissolved immediately after the start of the leaching test, indicating that these elements existed in highly soluble particles. After the rapid dissolution, their concentrations in the leachate gradually increased, possibly due to the dissolution of glassy phases. During the 1-week leaching test, the B and As concentrations in the leachate finally decreased. The addition of only small amounts of water to CFA (Sample A) for aging produce both alkaline and supersaturation conditions for the formation of several types of Ca-bearing secondary minerals such as calcite and ettringite, which are formed under alkaline conditions. Boron and As originally existing as highly soluble particles in CFA are expected to be incorporated into and/or sorbed on these secondary minerals as water-insoluble phases. Compared to non-aged CFA, their leachability from the aged sample A remained lower throughout the entire leaching test. Possibly due to these secondary minerals being formed on the CFA surface, B and As dissolutions associated with glassy phases are also prevented. In contrast, the pH of the leachate from CFA (sample B) at the beginning of the leaching test was acidic and then abruptly became alkaline. This means that water-soluble particles that can produce acidic conditions are also contained in these alkaline CFAs. Dissolution of these substances during aging makes it difficult to generate alkaline conditions in the CFA paste. Consequently, the formation of secondary minerals and the concomitant immobilization of toxic elements are prevented. 相似文献
90.