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131.
Papaya, a fruit crop cultivated in tropical and subtropical regions, is known for its nutritional benefits and medicinal applications. Here we report a 3x draft genome sequence of 'SunUp' papaya, the first commercial virus-resistant transgenic fruit tree to be sequenced. The papaya genome is three times the size of the Arabidopsis genome, but contains fewer genes, including significantly fewer disease-resistance gene analogues. Comparison of the five sequenced genomes suggests a minimal angiosperm gene set of 13,311. A lack of recent genome duplication, atypical of other angiosperm genomes sequenced so far, may account for the smaller papaya gene number in most functional groups. Nonetheless, striking amplifications in gene number within particular functional groups suggest roles in the evolution of tree-like habit, deposition and remobilization of starch reserves, attraction of seed dispersal agents, and adaptation to tropical daylengths. Transgenesis at three locations is closely associated with chloroplast insertions into the nuclear genome, and with topoisomerase I recognition sites. Papaya offers numerous advantages as a system for fruit-tree functional genomics, and this draft genome sequence provides the foundation for revealing the basis of Carica's distinguishing morpho-physiological, medicinal and nutritional properties.  相似文献   
132.
The recent discovery of superconductivity in the iron oxypnictide family of compounds has generated intense interest. The layered crystal structure with transition-metal ions in planar square-lattice form and the discovery of spin-density-wave order near 130 K (refs 10, 11) seem to hint at a strong similarity with the copper oxide superconductors. An important current issue is the nature of the ground state of the parent compounds. Two distinct classes of theories, distinguished by the underlying band structure, have been put forward: a local-moment antiferromagnetic ground state in the strong-coupling approach, and an itinerant ground state in the weak-coupling approach. The first approach stresses on-site correlations, proximity to a Mott-insulating state and, thus, the resemblance to the high-transition-temperature copper oxides, whereas the second approach emphasizes the itinerant-electron physics and the interplay between the competing ferromagnetic and antiferromagnetic fluctuations. The debate over the two approaches is partly due to the lack of conclusive experimental information on the electronic structures. Here we report angle-resolved photoemission spectroscopy (ARPES) of LaOFeP (superconducting transition temperature, T(c) = 5.9 K), the first-reported iron-based superconductor. Our results favour the itinerant ground state, albeit with band renormalization. In addition, our data reveal important differences between these and copper-based superconductors.  相似文献   
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Y Shi  H Zhao  Y Shi  Y Cao  D Yang  Z Li  B Zhang  X Liang  T Li  J Chen  J Shen  J Zhao  L You  X Gao  D Zhu  X Zhao  Y Yan  Y Qin  W Li  J Yan  Q Wang  J Zhao  L Geng  J Ma  Y Zhao  G He  A Zhang  S Zou  A Yang  J Liu  W Li  B Li  C Wan  Y Qin  J Shi  J Yang  H Jiang  JE Xu  X Qi  Y Sun  Y Zhang  C Hao  X Ju  D Zhao  CE Ren  X Li  W Zhang  Y Zhang  J Zhang  D Wu  C Zhang  L He  ZJ Chen 《Nature genetics》2012,44(9):1020-1025
Following a previous genome-wide association study (GWAS 1) including 744 cases and 895 controls, we analyzed genome-wide association data from a new cohort of Han Chinese (GWAS 2) with 1,510 polycystic ovary syndrome (PCOS) cases and 2,016 controls. We followed up significantly associated signals identified in the combined results of GWAS 1 and 2 in a total of 8,226 cases and 7,578 controls. In addition to confirming the three loci we previously reported, we identify eight new PCOS association signals at P < 5 × 10(-8): 9q22.32, 11q22.1, 12q13.2, 12q14.3, 16q12.1, 19p13.3, 20q13.2 and a second independent signal at 2p16.3 (the FSHR gene). These PCOS association signals show evidence of enrichment for candidate genes related to insulin signaling, sexual hormone function and type 2 diabetes (T2D). Other candidate genes were related to calcium signaling and endocytosis. Our findings provide new insight and direction for discovering the biological mechanisms of PCOS.  相似文献   
136.
文中针对高校传统网络实验室的教学资源封闭、设备利用率低、学生创新能力受限等问题,提出了一种基于Fre—eRADIUS的远程开放网络实验室管理平台的设计和实现,并结合电子科技大学中山学院远程开放实验实际教学情况,积极探讨了高校开放实验教学的管理模式和教学内容,为开放实验的研究和培养创新人才提供了有效的参考。  相似文献   
137.
This paper reports that the high pressure in situ angle dispersive x-ray diffraction and Raman scattering studies on CoPt and NiPt hollow nanospheres are performed by means of a diamond anvil cell for generating external pressure at room temperature.The crystal structures of both the CoPt and NiP hollow nanospheres keep stable up to about 41 GPa.Moreover,it shows that the hollow nanospheres possess higher bulk moduli than their bulk counterparts by using the frst-principles density functional theory.  相似文献   
138.
The Mg-chelatase H subunit is an abscisic acid receptor   总被引:3,自引:0,他引:3  
Shen YY  Wang XF  Wu FQ  Du SY  Cao Z  Shang Y  Wang XL  Peng CC  Yu XC  Zhu SY  Fan RC  Xu YH  Zhang DP 《Nature》2006,443(7113):823-826
Abscisic acid (ABA) is a vital phytohormone that regulates mainly stomatal aperture and seed development, but ABA receptors involved in these processes have yet to be determined. We previously identified from broad bean an ABA-binding protein (ABAR) potentially involved in stomatal signalling, the gene for which encodes the H subunit of Mg-chelatase (CHLH), which is a key component in both chlorophyll biosynthesis and plastid-to-nucleus signalling. Here we show that Arabidopsis ABAR/CHLH specifically binds ABA, and mediates ABA signalling as a positive regulator in seed germination, post-germination growth and stomatal movement, showing that ABAR/CHLH is an ABA receptor. We show also that ABAR/CHLH is a ubiquitous protein expressed in both green and non-green tissues, indicating that it might be able to perceive the ABA signal at the whole-plant level.  相似文献   
139.
The turnover of talents in West China enterprises seriously hinders their development. Therefore, the establishment of scientific human resource system is rather important. On the basis of survey to some West China enterprises, this paper analyzes the needs of employees, discovers that there are differences between the need hierarchy of these employees and the classic need theories, and studies the changes in need hierarchy and need strength among different employee groups.  相似文献   
140.
The shallow-water equations and pollutant convective-diffusive equation are transformed into curvilinear coordinate system. The anisotropic algebraic-stress turbulent model is introduced to simulate the turbulence items, and algebraic-stress turbulent model of planar 2-D pollutant convective-diffusive in curvilinear coordinates is build. The meandering channel with measured data of concentration in lab is adopted to validate the model, and the distribution figure of pollutant concentration field calculated through this model and that of the k - model, which show the model is superior to k -ε turbulent model in dealing with anisotropy character of flow.  相似文献   
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