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121.
The diversity of glutelin acidic polypeptides in rice cultivars collected from Northern Vietnam was characterized via sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS‐PAGE) and isoelectric focusing (IEF) electrophoresis. Glutelin acidic subunits were separated into four bands by molecular mass, as α‐1 (39 kDa), α‐2 (38 kDa), α‐3 (37.5 or 37 kDa) and α‐4 (34 or 33 kDa). One hundred and eighty‐five Vietnamese rice cultivars were divided into three types, based on differences in staining intensity and the molecular size of the α‐3 and α‐4 polypeptides derived from SDS‐PAGE analysis. Wide variation was also observed in the isoelectric point (pI) staining intensity, in addition to the absence/presence of pI bands detected via IEF analysis. A total of 16 pI bands, ranging from pI 6.30 to pI 7.52, were identified in the various local rice cultivars. The maximum and minimum of IEF bands detected were 14 and 10, respectively. The genetic variability index (H′) ranged from 0.280 to 0.820, which confirms that local rice cultivars from Northern Vietnam have diverse glutelin seed storage units.  相似文献   
122.
The potential of microsatellite markers for use in genetic studies has been evaluated in Allium cultivated species (Allium cepa, A. fistulosum) and its allied species (A. altaicum, A. galanthum, A. roylei, A. vavilovii). A total of 77 polymerase chain reaction (PCR) primer pairs were employed, 76 of which amplified a single product or several products in either of the species. The 29 AMS primer pairs derived from A. cepa and 46 microsatellites primer pairs from A. fistulosum revealed a lot of polymorphic amplicons between seven Allium species. Some of the microsatellite markers were effective not only for identifying an intraspecific F1 hybrid between shallot and bulb onion but also for applying to segregation analyses in its F2 population. All of the microsatellite markers can be used for interspecific taxonomic analyses among two cultivated and four wild species of sections Cepa and Phyllodolon in Allium. Generally, our data support the results obtained from recently performed analyses using molecular and morphological markers. However, the phylogeny of A. roylei, a threatened species with several favorable genes, was still ambiguous due to its different positions in each dendrogram generated from the two primer sets originated from A. cepa and A. fistulosum.  相似文献   
123.
A bovine myeloid antimicrobial peptide antimicrobial peptide (BMAP‐28) is a member of the cathelicidin family and acts as a component of innate immunity. There are few reports of susceptibility difference of methicillin‐resistant Staphylococcus aureus (MRSA) and susceptible strains (MSSA) against BMAP‐28. This study aims to clarify how a few amino acid substitutions of BMAP‐28 are related to its antimicrobial activity using four analog peptides of BMAP‐28. We also compared cellular fatty acid components of MSSA and MRSA using gas chromatography. We found that a few amino acid substitutions of BMAP‐28 do not change antimicrobial activity. It was also revealed that the percentage of cis‐11‐eicosenoic acid in total detected fatty acids of MRSA was significantly higher than that of MSSA. In addition, the percentage of palmitic acid in total detected fatty acids of MRSA tended to be lower than that of MSSA. Our results will provide new information to deal with the question of differences in bacterial susceptibility against BMAP‐28.  相似文献   
124.
To gain better understanding of rates of decay of wooden check dams with different structures under different climate conditions, several dams of this type were examined under different environmental conditions over a 3 to 5-year period post-construction. Because a linear relationship was found between the mean (μ) and standard deviation (σ) of pilodyn penetration depth, mean penetration depth was taken as the indicator of deterioration, and relationships with check dam structural features and climate data recorded by AMEDAS were investigated. Multiple linear regression analysis revealed that temperature, climate index (CI) computed from rain days, warmth index computed from daily and annual mean air temperature, and altitude were the climate variables with the most effect on the rate of decay. With regard to dam structural features, factors such as specific discharge rate, water through width, dam length, and dam height had the most effect. Accordingly, in an effort to summarize the effects of climatic conditions and structural features, CI, altitude, and dam height were extracted as the most significant explanatory variables, and a formula for prediction of μ was obtained for each factor for up to 5 years post construction. The results showed that by taking into consideration regional conditions and calculating CI values from AMEDAS data, it is possible to predict the extent of decay of wooden check dams.  相似文献   
125.
Decadal change in abundance of surface migratory myctophid fishes was examined in the Kuroshio region of the western North Pacific for the 35 yr from 1957 to 1994 in relation to the Kuroshio regime shift, indicated by changes in its transport volume and sea surface temperature in the early 1970s. Each year, samples were collected from the 0‐ to 1‐m depth layer at night, from January to March, at 83 stations on average. Ten species belonging to five genera occurred. Juveniles [standard length (SL) ≤ 40 mm] and adults (SL > 40 mm) of each species were analysed. In juveniles, Myctophum asperum, M. nitidulum, Symbolophorus evermanni and Centrobranchus brevirostris accounted for 91.1% of the total catch (7419 individuals), while M. nitidulum contributed 82.4% of the total adult catch (494 individuals). The abundance of juvenile S. evermanni, C. brevirostris and M. nitidulum showed prominent peaks in 1971, together with adult M. nitidulum. These peaks corresponded to extraordinarily high zooplankton abundance in the Kuroshio region in 1971, suggesting high recruitment success and low adult mortality in surface migratory myctophids. Smaller changes in abundance in other years were species‐specific, and the fluctuation patterns were mainly explained by year‐to‐year fluctuations in the strength of the Kuroshio and the geographical distribution of each species, i.e. an increased Kuroshio flow volume resulted in an increase in tropical species and a decrease in temperate species, but no change in the pan‐Kuroshio species.  相似文献   
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晋西不同林地状况对糙率系数n值影响的研究   总被引:13,自引:0,他引:13       下载免费PDF全文
在野外小区径流实验基础上,通过经转换的曼宁公式,对不同坡地地表的糙率系数n值进行了定量研究,结果表明,林地上的糙率系数n值与林地地表残存的枯落物量和生长的草量呈正相关关系,不同土地利用现状的地表糙率系数n值按由低到高的顺序排列,依次为土质路面,农耕地、核桃果园、人工剌槐林地、灌木林和人工油松林地,该还探讨了糙率系数n值与地表水分渗透量的关系。初步结果表明:糙率系数n值较大的地表其水分渗透能力地较  相似文献   
129.
Several iron-rich wood samples were investigated using Mössbauer spectroscopy to obtain information on the chemical state of the iron species contained in them. The Mössbauer spectrum of Japanese cedar (Cryptomeria japonica D. Don) wood containing iron species that originated from rusted nails exhibited a symmetrical doublet from a high-spin Fe(III) species, which is expected to be γ-FeOOH (lepidocrocite). Mössbauer absorption attributable to high-spin Fe(III) was observed for ancient buried wood samples of both Japanese cedar and Japanese cypress (Chamaecyparis obtusa Endlicher). Moreover, Mössbauer measurement indicated that the ancient buried Japanese cedar also possessed high-spin Fe(II) species.  相似文献   
130.
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