A rice heading-date-related mutant was isolated from a ^60Co-y-ray-induced mutation pool of Zhejing 22, a conventional japonica cultivar in Zhejiang Province, China. The mutant was characterized by a delayed heading d...A rice heading-date-related mutant was isolated from a ^60Co-y-ray-induced mutation pool of Zhejing 22, a conventional japonica cultivar in Zhejiang Province, China. The mutant was characterized by a delayed heading date of almost 20 d longer than the wild type plant. Genetic analysis revealed that the mutation was controlled by a single nuclear-encoded recessive gene that was designed as HD（t） （heading date tentatively）. To isolate the HD（t） gene, a map-based cloning approach was employed using 479 F2 mutant individual plants derived from the cross between the hd（t） mutant （japonica） x Zhenshan 97 （indica）. Finally, the HD（t） gene was mapped to an approximate 53 kb region between the insertion and deletion （InDel） markers of 10-61W and 10-66W on chromosome 10. According to the genome sequence of Nipponbare, the target region contains 11 annotated genes. It is helpful for future cloning of HD（t） gene based on this fine mapping results.展开更多
AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic...AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic cancer patients had their first EUS-FNA between February 2001 and December 2017. Among them, 201 who underwent EUS-FNA for pancreatic head lesions were included in this study. EUS-FNA was performed by the push method in 85 patients, the pull method in 101 patients and both the push and pull methods in 15 patients. After propensity score matching(age, sex, tumor diameter, and FNA needle), 85 patients each were stratified into the push and pull groups. Patient characteristics and EUSFNA-related factors were compared between the two groups.RESULTS Patient characteristics were not significantly different between the two groups. The distance to lesion was significantly longer in the push group than in the pull group(13.9 ± 4.9 mm vs 7.0 ± 4.9 mm, P < 0.01). The push method was a significant factor influencing the distance to lesion(≥ median 10 mm)(P < 0.01). Additionally, tumor diameter ≥ 25 mm(OR = 1.91, 95%CI: 1.02-3.58, P = 0.043) and the push method(OR = 1.91, 95%CI: 1.03-3.55, P = 0.04) were significant factors contributing to the histological diagnosis of malignancy.CONCLUSION The pull method shortened the distance between the endoscope and the lesion and facilitated EUS-FNA of pancreatic head cancer. The push method contributed to the histological diagnosis of pancreatic head cancer using EUS-FNA specimens.展开更多
从常规粳稻常优94后代中筛选到一份自然突变的抽穗期延迟的类树稻突变体lhd3(leafy head 3)。在短日照条件下,与野生型比较,lhd3突变体在生长后期,上部节间会继续长出叶片(一般为3片)和高位分蘖,类似于树的侧枝生长,抽穗期延迟,但基部...从常规粳稻常优94后代中筛选到一份自然突变的抽穗期延迟的类树稻突变体lhd3(leafy head 3)。在短日照条件下,与野生型比较,lhd3突变体在生长后期,上部节间会继续长出叶片(一般为3片)和高位分蘖,类似于树的侧枝生长,抽穗期延迟,但基部分蘖数不受影响。经典遗传分析表明,lhd3与籼稻南京6号的F2群体中,正常植株与类树稻植株的分离比符合3∶1,说明此性状受单隐性基因控制。利用该群体进行图位克隆,将LHD3基因定位在水稻第1染色体短臂的两个新发展的STS标记wpla3和wpla25之间。再利用5个新发展的STS和CAPS标记,最终将该基因精细定位在WX6和CAPS1两个标记之间,物理距离约为60 kb。通过水稻基因组注释系统共预测到10个开放阅读框(ORF)。对该基因的进一步克隆将有助于阐明水稻生育期和叶原基发育调控机理。展开更多
Full face rock tunnel boring machine（TBM） has been widely used in hard rock tunnels, however, there are few published theory about cutter-head design, and the design criteria of cutter-head under complex geological ...Full face rock tunnel boring machine（TBM） has been widely used in hard rock tunnels, however, there are few published theory about cutter-head design, and the design criteria of cutter-head under complex geological is not clear yet. To deal with the complex relationship among geological parameters, cutter parameters, and operating parameters during tunneling processes, a cutter-head load model is established by using CSM（Colorado school of mines） prediction model. Force distribution on cutter-head under a certain geology is calculated with the new established load model, and result shows that inner cutters bear more force than outer cutters, combining with disc cutters abrasion; a general principle of disc cutters＇ layout design is proposed. Within the model, the relationship among rock uniaxial compressive strength（UCS）, penetration and thrust on cutter-head are analyzed, and the results shows that with increasing penetration, cutter thrust increases, but the growth rate slows and higher penetration makes lower special energy（SE）. Finally, a fitting mathematical model of ZT（ratio of cutter-head torque and thrust） and penetration is established, and verified by TB880 E, which can be used to direct how to set thrust and torque on cutter-head. When penetration is small, the cutter-head thrust is the main limiting factor in tunneling; when the penetration is large, cutter-head torque is the major limiting factor in tunneling. Based on the new cutter-head load model, thrust and torque characteristics of TBM further are researched and a new way for cutter-head layout design and TBM tunneling operations is proposed.展开更多
Heading date(flowering time)determines the adaptability of cultivars to different environments.We report the fine mapping and candidate gene analysis of qHD1b,a quantitative trait locus(QTL)responsible for early flowe...Heading date(flowering time)determines the adaptability of cultivars to different environments.We report the fine mapping and candidate gene analysis of qHD1b,a quantitative trait locus(QTL)responsible for early flowering that was derived from common wild rice(O.rufipogon)under both short-day and longday conditions.The introgression line IL7391,which carried segments from common wild rice in a Zhonghui 8015(ZH8015)background,exhibited early heading compared to the background and was crossed with ZH8015 to generate BC_(5)F_(2:3) families for QTL analysis.This enabled the identification of two heading-date QTL,named qHD1b and qHD7,of which the first was selected for further research.High-resolution linkage analysis was performed in BC_(5)F_(4:5) and BC_(5)F_(6) populations,and the location of qHD1b was confined to a 112.7-kb interval containing 17 predicted genes.Five of these genes contained polymorphisms in the promoter or coding regions and were thus considered as candidates.Expression analysis revealed a positive association between LOC_Os01g11940 expression and early heading.This locus was annotated as OsFTL1,which encodes an ortholog of Arabidopsis Flowering Locus T and was the most likely candidate gene for qHD1b.Our study revealed that qHD1b acts as a floral activator that promotes flowering by up-regulating Ehd1,Hd3a,RFT1,OsMADS14,and OsMADS15 under both shortday and long-day conditions.Field experiments showed that qHD1b affected several yield-related agronomic traits including 1000-grain weight and grain length.qHD1b could be useful for marker-assisted selection and breeding of early-maturing cultivars.展开更多
基金supported by the Chinese Ministry of Agriculture(Grant Nos.200803034 and 2011ZX08001001)the Zhejiang Provincial and the National Natural Science Foundation of China(Grant Nos.Y3080361 and 31071207)+2 种基金the Science and Technology Department of Zhejiang Province,China(Grant No.2004C12020)the Special Fund for Agro-scientific Research in the Public Interest(Grant No.201103007)the Special Fund of Zhejiang Academy of Agricultural Science,China
文摘A rice heading-date-related mutant was isolated from a ^60Co-y-ray-induced mutation pool of Zhejing 22, a conventional japonica cultivar in Zhejiang Province, China. The mutant was characterized by a delayed heading date of almost 20 d longer than the wild type plant. Genetic analysis revealed that the mutation was controlled by a single nuclear-encoded recessive gene that was designed as HD（t） （heading date tentatively）. To isolate the HD（t） gene, a map-based cloning approach was employed using 479 F2 mutant individual plants derived from the cross between the hd（t） mutant （japonica） x Zhenshan 97 （indica）. Finally, the HD（t） gene was mapped to an approximate 53 kb region between the insertion and deletion （InDel） markers of 10-61W and 10-66W on chromosome 10. According to the genome sequence of Nipponbare, the target region contains 11 annotated genes. It is helpful for future cloning of HD（t） gene based on this fine mapping results.
文摘AIM To evaluate the efficacy of endoscopic ultrasoundguided fine needle aspiration(EUS-FNA) of pancreatic head cancer when pushing(push method) or pulling the echoendoscope(pull method).METHODS Overall, 566 pancreatic cancer patients had their first EUS-FNA between February 2001 and December 2017. Among them, 201 who underwent EUS-FNA for pancreatic head lesions were included in this study. EUS-FNA was performed by the push method in 85 patients, the pull method in 101 patients and both the push and pull methods in 15 patients. After propensity score matching(age, sex, tumor diameter, and FNA needle), 85 patients each were stratified into the push and pull groups. Patient characteristics and EUSFNA-related factors were compared between the two groups.RESULTS Patient characteristics were not significantly different between the two groups. The distance to lesion was significantly longer in the push group than in the pull group(13.9 ± 4.9 mm vs 7.0 ± 4.9 mm, P < 0.01). The push method was a significant factor influencing the distance to lesion(≥ median 10 mm)(P < 0.01). Additionally, tumor diameter ≥ 25 mm(OR = 1.91, 95%CI: 1.02-3.58, P = 0.043) and the push method(OR = 1.91, 95%CI: 1.03-3.55, P = 0.04) were significant factors contributing to the histological diagnosis of malignancy.CONCLUSION The pull method shortened the distance between the endoscope and the lesion and facilitated EUS-FNA of pancreatic head cancer. The push method contributed to the histological diagnosis of pancreatic head cancer using EUS-FNA specimens.
文摘从常规粳稻常优94后代中筛选到一份自然突变的抽穗期延迟的类树稻突变体lhd3(leafy head 3)。在短日照条件下,与野生型比较,lhd3突变体在生长后期,上部节间会继续长出叶片(一般为3片)和高位分蘖,类似于树的侧枝生长,抽穗期延迟,但基部分蘖数不受影响。经典遗传分析表明,lhd3与籼稻南京6号的F2群体中,正常植株与类树稻植株的分离比符合3∶1,说明此性状受单隐性基因控制。利用该群体进行图位克隆,将LHD3基因定位在水稻第1染色体短臂的两个新发展的STS标记wpla3和wpla25之间。再利用5个新发展的STS和CAPS标记,最终将该基因精细定位在WX6和CAPS1两个标记之间,物理距离约为60 kb。通过水稻基因组注释系统共预测到10个开放阅读框(ORF)。对该基因的进一步克隆将有助于阐明水稻生育期和叶原基发育调控机理。
基金Supported by National Natural Science Foundation of China(Grant No.51275339)National Basic Research Program of China(973 Program,Grant No.2013CB035402)
文摘Full face rock tunnel boring machine（TBM） has been widely used in hard rock tunnels, however, there are few published theory about cutter-head design, and the design criteria of cutter-head under complex geological is not clear yet. To deal with the complex relationship among geological parameters, cutter parameters, and operating parameters during tunneling processes, a cutter-head load model is established by using CSM（Colorado school of mines） prediction model. Force distribution on cutter-head under a certain geology is calculated with the new established load model, and result shows that inner cutters bear more force than outer cutters, combining with disc cutters abrasion; a general principle of disc cutters＇ layout design is proposed. Within the model, the relationship among rock uniaxial compressive strength（UCS）, penetration and thrust on cutter-head are analyzed, and the results shows that with increasing penetration, cutter thrust increases, but the growth rate slows and higher penetration makes lower special energy（SE）. Finally, a fitting mathematical model of ZT（ratio of cutter-head torque and thrust） and penetration is established, and verified by TB880 E, which can be used to direct how to set thrust and torque on cutter-head. When penetration is small, the cutter-head thrust is the main limiting factor in tunneling; when the penetration is large, cutter-head torque is the major limiting factor in tunneling. Based on the new cutter-head load model, thrust and torque characteristics of TBM further are researched and a new way for cutter-head layout design and TBM tunneling operations is proposed.
基金supported by the National Natural Science Foundation of China(31871604,32071996,and 31961143016)the National Key Research and Development Program of China(2020YFE0202300)+1 种基金the Fundamental Research Funds of Central Public Welfare Research Institutions(CPSIBRFCNRRI-202102)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP2013-CNRRI).
文摘Heading date(flowering time)determines the adaptability of cultivars to different environments.We report the fine mapping and candidate gene analysis of qHD1b,a quantitative trait locus(QTL)responsible for early flowering that was derived from common wild rice(O.rufipogon)under both short-day and longday conditions.The introgression line IL7391,which carried segments from common wild rice in a Zhonghui 8015(ZH8015)background,exhibited early heading compared to the background and was crossed with ZH8015 to generate BC_(5)F_(2:3) families for QTL analysis.This enabled the identification of two heading-date QTL,named qHD1b and qHD7,of which the first was selected for further research.High-resolution linkage analysis was performed in BC_(5)F_(4:5) and BC_(5)F_(6) populations,and the location of qHD1b was confined to a 112.7-kb interval containing 17 predicted genes.Five of these genes contained polymorphisms in the promoter or coding regions and were thus considered as candidates.Expression analysis revealed a positive association between LOC_Os01g11940 expression and early heading.This locus was annotated as OsFTL1,which encodes an ortholog of Arabidopsis Flowering Locus T and was the most likely candidate gene for qHD1b.Our study revealed that qHD1b acts as a floral activator that promotes flowering by up-regulating Ehd1,Hd3a,RFT1,OsMADS14,and OsMADS15 under both shortday and long-day conditions.Field experiments showed that qHD1b affected several yield-related agronomic traits including 1000-grain weight and grain length.qHD1b could be useful for marker-assisted selection and breeding of early-maturing cultivars.
