Direct measurements of mid-depth circulation in the Shikoku basin by tracking SOFAR floats   总被引：1，自引：0，他引：1  

Keisuke Taira  Shoji Kitagawa  Katsuto Uehara  Hiroshi Ichikawa  Hiroyuki Hachiya  Toshihiko Teramoto 《Journal of Oceanography》1990,46(6):296-306

Mid-depth circulation of the Shikoku Basin was measured by tracking four SOFAR floats drifting at the 1,500 m layer. Two floats were released on 17 April 1988 at 30°N, 135°59E and tracked for 433 days. Another two were released on 3 November 1988 at 29°52N and 133°25E, and tracked for 234 days. Two floats flowed clockwise around the Shikoku Warm Water Mass with a diameter of 400 km centered at 31°N and 136°E and a mean drift speed of 4.5 cm sec^–1. One of the floats showed about ten counterclockwise rotations with a period of about 8 days and a maximum speed of 80 cm sec^–1 in the sea area west to the Izu Ridge. In the east to Kyushu, a southward flow was observed under the northward flowing Kuroshio. The southward flow of 4 cm sec^–1 drift speed was considered to be a part of the counterclockwise circulation at deep layers along the perimeter of the Shikoku Basin. One float remained for 234 days in a limited area of 100 km by 150 km in the western part of the basin.  相似文献   

真鲷脂蛋白脂肪酶基因顺式元件PPRE及在肝脏活体调控作用   总被引：7，自引：0，他引：7  

梁旭方  李月琴  李贵生  白俊杰  劳海华  Hiromi Oku  Hiroshi Y.OGATA 《热带海洋学报》2004,23(4):49-55

从血液提取总DNA并构建基因组文库,克隆海水鱼真鲷(Pagrosomusmajor)脂蛋白脂肪酶(LPL)基因5′侧翼区序列,再通过竞争性聚合酶链式反应(PCR)方法,定量研究饲料中添加不同饱和度脂肪酸对其肝脏LPL基因mRNA表达水平的影响。结果表明,真鲷LPL基因5′侧翼区序列中存在顺式元件过氧化物酶体增殖物反应元件,其序列为TGAAGA TGACAT,与TATA(CATAA)盒序列相隔211bp;与喂饲料对照组比较,添加10%油酸可增加真鲷肝脏LPL基因表达水平,但差异并不显著(p>0.05)。用亚油酸或n 3高不饱和脂肪酸混合物取代添加油酸的一半(占饲料添加量的5%)后,导致真鲷肝脏LPL基因表达水平升高并出现显著性变化(p<0.05)。对真鲷肝脏LPL基因诱导表达随饲料中的脂肪酸不饱和度增加而增加,表明在活体条件下脂肪酸对真鲷肝脏LPL基因表达的诱导作用可能与脂肪酸的氧化代谢有关。n 3高不饱和脂肪酸通过过氧化物酶体增殖物激活受体诱导真鲷肝脏LPL基因表达,使真鲷食物脂质供应水平与其肝脏脂肪酸氧化代谢强度调控偶联起来,可能是真鲷对高脂食物(特别是富含n 3高不饱和脂肪酸食物)的一种适应。  相似文献   

Analytical expansions of torque-free motions for short and long axis modes     

Hiroshi Kinoshita 《Celestial Mechanics and Dynamical Astronomy》1992,53(4):365-375

Torque-free motion of a rigid body is integrable and its solution is expressed in terms of elliptic functions and elliptic integrals. The conventional analytical expression of the solution, however, is complicated and not suitable for hand-calculation. Recently the rotational motions of small celestial bodies in the solar system are frequently investigated by numerically integrating the equations of motion instead of using the analytical solution, since the numerical evaluation of the analytical and exact solution is a little bit difficult. As the observational accuracy of the rotational motions of the small bodies in the solar system is quite low, what we need for the reduction of these observations are rough estimates of the period of Eulerian motion ( or the free precession period) and the amplitudes of the main periodic terms. Here we give simple analytical expansions of torque-free motions for short- and long-axis modes, which are correct up to the second-order of a small parameter. These expressions include only trigonometric functions and are easily evaluated by hand calculation for estimates of the essential quantities from which we can determine a global rotational motion of the torque-free motion. They can also be used as the zero-th order solution in a perturbation method, when the motion is perturbed by external torques.  相似文献