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71.
72.
Travel and Activity Choices for Transit Travelers at Terminals with Dynamic Information Provision 下载免费PDF全文
This study explores the impacts of providing dynamic information on travelers' behavior and the induced demand for terminal‐surrounding activities. A nested logit model was used to identify the important factors, and a questionnaire was designed to explore the preference of travelers regarding activities and travel choices. Adopting dynamic information was found to have a significant influence on travel decisions. The results show that an increased duration of activity participation may accompany an alteration of departure time or mode choice. The results also show that the use of dynamic information for travelers is related to induced activity participation and travelers' socioeconomic characteristics. The content of the dynamic information should be designed in accordance with the preference of travelers to encourage travelers participating in terminal‐surrounding activities. 相似文献
73.
Multiplex PCR genotyping for five bacterial blight resistance genes applied to marker‐assisted selection in rice (Oryza sativa) 下载免费PDF全文
Bacterial blight (BB) is the most economically damaging disease of rice in Asia and other parts of the world. In this study, a multiplex PCR genotyping method was developed to simultaneously identify genotypes of five BB resistance genes, Xa4, xa5, Xa7, xa13 and Xa21. The resistance R alleles were amplified using five functional markers (FMs) to generate amplicons of 217, 103, 179, 381 and 595 bp in IRBB66. Amplicons of 198, 107, 87, 391 and 467 bp corresponded to susceptible alleles in Taiwanese japonica rice cultivars. In backcross breeding programmes, the multiplex PCR assay was integrated into selection from a population using BB resistance donor IRBB66 crossed to rice cultivar ‘Tainung82’. Two plants with homozygosity for Xa4, xa5, Xa7, xa13 and Xa21 were selected from 1100 BC2F2 plants. In addition, the five BB resistance genes were also accurately identified in F2 populations. This multiplex PCR method provides a rapid and efficient method for detecting various BB resistance genes, which will assist in pyramiding genes to improve durability of BB resistance in Taiwanese elite rice cultivars. 相似文献
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75.
The collection of epididymal sperm may be a valuable tool for canine reproduction especially since it can enable collection of cells after death of a valuable dog. The aim of the present study was to evaluate the viability of epididymal sperm after freeze-thawing. Epididymides were obtained from four adult dogs by elective orchiectomy. The caudal portion of the epididymides and part of the deferential ducts were squeezed by means of an anatomic clamp into a Petri dish containing either 0.9% saline solution (Group 1) or Ringer solution without lactate (Group 2). Samples were centrifuged at 800 × g for 10 min, the supernatant was removed and the pellet was diluted in one step with a Tris/citric acid/OEP (Orvus Es Paste) extender containing 7% glycerol and subjected to semen freezing. Oocytes were obtained from canine ovaries, after ovariohysterectomy. Only oocytes that were approximately 100 μm in diameter, with a dark ooplasm surrounded by three- or four-well formed cumulus cell layers were used for sperm testing. Frozen semen samples were thawed in a water bath at 70°C for 8 s and analysed at room temperature for sperm motility and velocity. Oocytes were incubated with spermatozoa in humidified atmosphere containing 5% CO2 at 38°C for 18 h. Morphological and functional characteristics of spermatozoa were similar in both groups. However, the percentage of sperm cells bound to oocytes was significantly higher in Group 2 than in Group 1. This result suggests that the Ringer solution without lactate was a more suitable medium for collecting epididymal canine sperm than 0.9% saline. 相似文献
76.
南通棉花枯萎病菌对22个棉花品种致病性的田間和盆栽試驗说明:中棉品种如辽阳一号、鶯湖棉、长丰黑籽、常紫一号、南通白花鸡脚桠鈴果、云南布沼土棉等抗病性比較強,以中棉为母本的中印杂交棉的抗病性也較強;陆地棉和海島棉一般感病程度都較高,但四川选育的陆地棉品种52—128則具有一定的抗病性。将枯萎病菌接种到甘藷等27种作物上,均未感病。五个地区的棉花枯萎病菌致病性的盆栽試驗说明:四川、陝西、辽宁的病原菌致病力較強,江苏的其次,安徽的最弱。以葡萄糖、果糖、半乳糖、甘露糖、乳糖、蔗糖、菊糖、溶解淀粉、阿拉伯糖醇等九种糖和糖醇为碳素营养料时,除四川的病原菌在以半乳糖为碳素营养料时生长中等外,其他都生长旺盛。不同地区病原菌的色素形成、小型孢子、大型孢子和厚膜孢子的产生,随碳素营养料的不同而有所差異。 相似文献
77.
Our earlier studies indicated the high expression of a UV-damaged-DNA binding activity in zebrafish (Danio rerio) embryos at 12?h postfertilization (hpf). Two 30- to 35-kDa polypeptides homologous to the N-terminal lipovitellin 1 (Lv1) domain of the 150-kDa zebrafish vitellogenin 1 (zfVg1) were identified as the damage recognition factors in zebrafish extracts, and the metal-chelating agent 1,10-phenanthroline (OP) was found to inhibit the embryonic UV-damaged-DNA binding activity. This study further explored the DNA damage-sensing components in 12 hpf zebrafish extracts. UV-damaged-DNA binding proteins were enriched from zebrafish extracts by isoelectrofocusing. Both OP-sensitive and OP-stimulated, UV-damaged-DNA binding activities were detected in fractionated zebrafish extracts. Two-dimensional gel electrophoresis of proteins captured by an immobilized oligonucleotide carrying a UV-induced (6-4)photoproduct (6-4PP) revealed a 25-kDa polypeptide as the major 6-4PP-binding factor in an OP-stimulated fraction. Three 25-kDa factors that bound weakly to 6-4PPs were also isolated. The four polypeptides having pIs between 7.0 and 7.3 were unreactive to an anti-zfVg1 antibody targeting the Lv1 domain. Mass spectral analysis showed the appearance of amino acid sequences LPIIVTTYAK and IPEITMSK in all 25-kDa polypeptides and sequences exactly matching those contained in the four factors exist only in the C-terminal Lv2 domain of zfVg1, reflecting the origination of these factors from enzymatic cleavage of the Lv2 domain at slightly different positions. The OP-stimulated fraction produced a much stronger UV-dependent DNA incision activity in the presence than in the absence of OP, suggesting the association of these factors with DNA damage repair under metal-deficient conditions. 相似文献
78.
Chih-Wei Hsu Shu-Chuan Tsai Shu Chane Shen Su Mei Wu 《Fish physiology and biochemistry》2014,40(5):1587-1599
The aims of the present study are to determine whether triiodothyronine (T3) and/or thyroxine (T4) in tilapia larvae is gifted through the mother, and to investigate the change profiles of thyrotropin (TSH), thyroid follicular cells and type I deiodinase (D1) gene expression following larval development. T3 and T4 contents were measured using radioimmunoassay, thyrotropin was observed using immunocytochemistry, and the D1 gene was cloned and measured using real-time PCR. Results indicated that the β-TSH-immunoreactive cells (thyrotropin ICC) signals were detected at 9 dph (i.e., 9 days of post-hatching). Thyroid follicular cells were observed first at 3 dph, while the T3 contents of the whole body gradually decreased before 11 dph. T4 contents were detected until 13 dph, with higher secretion during 19–21 dph. In addition, the T3 synthesis was not inhibited by thiourea (TU) before 13 dph, but the TU response in the larvae appeared after 13 dph. Type I deiodinase (D1: GenBank accession number KC591724) was found to contain 2444 bases and encoded 248 amino acids. The D1 mRNA expression began to increase at 13 dph, with a higher expression during 15–19 dph. These results suggested that the T3 contents were maternally derived before 13 dph. Both thyroid hormonal changes and some parameters related to thyroid hormone synthesis in ontogenetic tilapia are discussed. 相似文献
79.
Eucalypt plantations are expanding rapidly in Australia, and their value for native fauna requires investigation. The relative conservation value of young eucalypt plantations was investigated through assessment of avifauna richness, abundance and composition using transect surveys incorporating point counts in five broad habitat types—dryland forests, riparian forests, dryland plantations, riparian plantations, and riparian pastures (strips of riparian vegetation surrounded by pastures). A total of 73 species were recorded during formal surveys. Species richness and abundance were comparable among all habitat types except dryland plantations, which supported fewer species and in lower numbers. The avifauna assemblage differed according to broad habitat types. Forest habitats (dryland and riparian) harboured more forest- and woodland-dependent species, and a greater abundance of nectarivores and insectivores. Riparian plantations supported a similar number of forest- and woodland-dependent species to forest habitats, but also retained some open-country species. Riparian pastures had the highest cumulative species richness, reflecting a diverse mix of forest- and woodland-dependent birds and open-country species. It was the preferred habitat type for granivores and vertebrate eaters. Dryland plantations were dominated by common species and omnivores, and supported fewer forest- and woodland-dependent birds, insectivores and frugivores compared with other habitat types. The presence of riparian strips increased avifauna diversity and abundance in plantations and pastures to a greater extent than predicted by the proportional area of riparian habitat. The importance of riparian habitats needs to be recognised and incorporated into management policies if biodiversity conservation is to be an objective of plantation establishment. 相似文献
80.
The successful development of phenology models from field studies depends on many factors, some of which are entirely under the control of pest managers. For example, one such factor is the choice of method for calculating thermal units. In this study, we have demonstrated that four methods for calculating thermal units provided for acceptable predictions of one phenological event of one insect species, while another method for calculating thermal units did not. The measure of central tendency (mean or median) that is used to estimate lower developmental temperatures and required thermal summations is another factor that pest managers can control when developing phenology models from field studies. Here, we show that predictions that were made when using phenology models based on median lower developmental temperatures and median required thermal summations were superior to predictions that were made when using phenology models based on mean lower developmental temperatures and mean required thermal summations. The use of bootstrap vs. non-bootstrap estimates of lower developmental temperatures and required thermal summations is yet another factor that pest managers can control when developing phenology models from field studies. In this study, we found that calculating and using bootstrap estimates of lower developmental temperatures and required thermal summations in phenology models did not improve the predictions of one phenological event for one insect species. The implications of these and other findings are discussed. 相似文献