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简介：《飞屋环游记》中美丽神秘的“天堂瀑布”真的存在吗？其实它的原型就是世界最高的瀑布——位于南美洲委内瑞拉的天使瀑布！

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简介：Thesemightyfallsareoneofthegreatnaturalwondersoftheworldalthoughtheyarenot,infact,nearlythehighestintheworld-theKaieteurFalls,forinstance,inBritishGuianabeingfivetimesashigh.TheyarepartlyinCanadaandpartlyintheUnitedStates,astheboundarybetweenthetwocountriesfollowstheRiverNiagara.ThisflowsfromLakeErieintoLakeOntario,andinitscourse

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简介：一、学区概况MenomoneeFalls学区位于美国威斯康星州密尔沃基市(Milwaukee)西北的一个效区.整个学区共有学生4300名,350多位教师.学区现有各级学校7所,其中小学4所,中间学校1所(笔者注:美国在1960年代始用的一种学校类型,目的是改进从初等教育向中等教育的过渡,通常包括5/6-8年级,强调课程的试探作用和逐渐增强学生的独立性.宗旨是为10-14岁的早期青年期的学生的特殊需要服务),初级中学1所,高中1所.

简介：AbstractWe reported two cases of jockeys who sustained fracture/dislocation of the mid-thoracic spine due to traumatic falls during horse racing. We examined the injury mechanism based upon the patients’ diagnostic images and video footage of races, in which the accidents occurred. Admission imaging of patient 1 (a 42 years old male) revealed T5 burst fracture with bony retropulsion of 7 mm causing complete paralysis below T5/6. There existed 22° focal kyphosis at T5/6, anterolisthesis of T5 relative to T6, T5/6 disc herniation, cord edema and epidural hemorrhage from T4 through T6, and cord injury from C3 through C6. Admission imaging of patient 2 (a 23 years old male) revealed T4/5 fracture/dislocation causing incomplete paralysis below spinal level. There existed compression fractures at T5, T6, and T7; 4 mm anterior subluxation of T4 on T5; diffuse cord swelling from T3 through T5; comminuted fracture of the C1 right lateral mass; right frontal traumatic subarachnoid hemorrhage; and extensive diffuse axonal injury. The injuries were caused by high energy flexion-compression of the mid-thoracic spine with a flexed posture upon impact. Our results suggest that substantially greater cord compression occurred transiently during trauma as compared to that documented from admission imaging. Video footage of the accidents indicated that the spine buckled and failed due to abrupt pocketing and deceleration of the head, neck and shoulders upon impact with the ground combined with continued forward and downward momentum of the torso and lower extremities. While a similar mechanism is well known to cause fracture/dislocation of the cervical spine, it is less common and less understood for mid-thoracic spine injuries. Our study provides insight into the etiology of fracture/dislocation patterns of the mid-thoracic spine due to falls during horse racing.

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