迪拜的奇迹

迪拜是一个充满奇迹的地方，虽然它只是阿联酋的第二大城市，但奇迹却使它的知名度远在首都阿布扎比之上。这里出现了无数“第一”：世界上最高的楼，最昂贵的人工高尔夫球场，最大的室内滑雪场，被称为“世界第八大奇迹”的人工海岛……     

电影院、停车场、高尔夫球场，甚至监狱在美国都能做REITs!

REITs的发展，早已偏离美国国会制定规则的初衷。它原想通过地产的证券化，让投资人在更广泛的领域，享受到房地产增值带来的收益，现在反而使房地产开发与各行业的地产需求结合起来，使他们得以摆脱物业投入的负担，快速发展。[编者按]     

Agrobacterium-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass ( Agrostis palustris Huds. ) cv. Regent and colonial bentgrass ( Agrostis Tenuis Sibth. F1. Oxen. ) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4-7 days and then co-cultivated with Agrobacterium tumefaciens, LBA4404,which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR) . After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12-15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2-3 months of selection, the actively growing calli of ‘Regent‘ and ‘Ti-ger‘ were transferred to MS medium with 12-15 mg/L PPT and 250 mg/L cefotaxime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4 % of herbi-cide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.