Transforaminal lumbar interbody fusion for traumatic lumbar spondylolisthesis

To evaluate the clinical outcome, effectiveness and safety of the surgical management of traumatic lumbar spondylolisthesis with transforaminal lumbar interbody fusion (TLIF) with short segmental instrumentation fixation. A retrospective review of a consecutive series of 24 patients with traumatic lumbar spondylolisthesis treated with TLIF procedure was carried out. Intraoperative spinal cord monitoring was used to confirm the peripheral neural function intact during the reduction of the spondylolisthesis. Preoperative clinical and radiographic evaluation of all cases were originally collected prospectively. Data regarding blood loss, operative time, duration of hospital stay, radiographic fusion, instrumentation failure and clinical result were collected and observed at regular follow-up periods. All patients were engaged in high-energy accidents in the lower back and 16 patients had concomitant injuries. The mean operative time was 124 min, mean blood loss was 350 mL, and mean hospital stay was 6.5 days. There were no complications such as incision infection, cerebrospinal fluide (CSF) leakage and nerve root injury and so on. All patients demonstrated a solid lumbar interbody fusion within 4 months, and no evidence of spondylolisthesis correction loss, instrumentation failure and loosing. They all were completely asymptomatic, with normal neurologic findings, and had resumed their previous level of physical activities on the final follow-up. Meticulous clinical examination and careful imaging assessment could assist an early diagonosis in cases of traumatic lumbar spondylolisthesis. Performing open reduction and the TLIF procedure as soon as possible could restore segmental stability and painless function. The TLIF procedure was a safe, effective technique to treat traumatic lumbar spondylolisthesis.     

Access control policies without inside queues: Their properties and public policy implications

An access control policy that eliminates all queues beyond the entry points to a network has obvious benefits, which include smooth travel and predictable travel times inside the network. Yet it has never been proven, to the best of our knowledge, whether excluding inside queues yields sub-optimal network performance or, in other words, allowing inside queues can actually further reduce the system travel cost. Moreover, it is not clear whether an optimal control policy derived from efficiency considerations can also be a fair policy to all road users. This paper provide answers to these questions in the context of a monocentric network. By analyzing the structure of the access control problem considering all feasible policies (with/without inside queues), we show that the minimal system cost realizable by access control can be obtained without directly solving a non-convex optimization program, and can indeed always be achieved by a control policy excluding all of the inside queues. These optimal policies are defined by a polyhedral set and a Finite Generation Algorithm can be applied to derive the analytical form of this set. The optimal policies are not unique in general, thus making it possible to achieve both minimal system cost and fairness simultaneously.     

襄阳市内环线工程汉江三桥索塔锚固区足尺模型试验研究

襄阳汉江三桥主桥索塔上塔柱为预应力混凝土结构,斜拉索锚固区构造和受力状态均较为复杂。通过制作索塔第25节段的足尺模型进行加载试验,并结合有限元计算及理论分析,对斜拉索索塔锚固区的应力大小、应力分布、应力流方向等局部应力状态以及抗裂性、承载力进行研究,对设计的合理性进行分析评价,确保结构受力的合理性和安全性。研究结果表明,试验加载至最大荷载1.7 P时,模型结构仍然处于弹性工作状态,模型混凝土表面未出现可见裂缝,说明结构具有足够的安全度,索塔锚固区的设计是合理的。     

西南某变电站场地适宜性评估研究

西南山区山高谷深,极易发生各类地质灾害。对变电站站址地质环境条件进行了详细论述,对地质灾害的类型（危岩崩塌体）、分布进行阐述,对工程建设可能引发或加剧及工程本身遭受的灾害进行了综合评估,提出了防治措施建议。     

超偏载检测装置运用中误报的常见原因分析

从超偏载检测装置位置、设备基础变化、车号设备故障、超偏载检测装置故障、计算机病毒影响、列车编组情况等方面，分析超偏载检测装置运用中造成误报警的原因。     

安全港口的法律问题

随着国际海上运输业务的发展，各航运公司的租船营运也越来越普遍，本文是想通过对期租和程租两种情况下，有关“安全港口”的责任期间及责任归属等问题的探讨，希望能够与各位船长和同行达成共识。     

在线检验技术在重卡行业中的应用

工业2025智能智造核心之一为大规模个性化定制产品的柔性协同生产。产品的多样性、差异性给生产检验环节带来了新的课题,如何高效的检验批量差异产品。通过丰富的传感器和摄像头数据采集,系统比对、结果跟踪组成生产在线检验系统。提升了生产环节产品检验效率,保证产品质量和一致性。     

新型埋刮板式筒仓清仓机

1 引言 筒仓是散粮码头、粮库等场所最主要的粮食储备设施.早期的筒仓多为钢筋混凝土锥底结构,物料靠自流卸出筒仓.但受其自身结构的限制,筒仓底部约有30%的空间得不到利用,经济性较差.为此,近年来国内新建或改建的筒仓多采用大容量钢板式平底结构.这种结构型式的筒仓既降低了工程造价,又提高了筒仓的仓储利用率.但因其仓底均为平面,出仓时有相当一部分粮食不能自流卸出.     

冷箱干用，天使还是魔鬼

冷箱干用(N O N—O PER A TIN G R EE FER,简称N O R),是指利用正常适货的冷箱,装运非冷藏货物出口的一种特殊业务操作。业内普遍认为,这种业务既可以在舱位有限的情况下实现冷藏箱向缺箱点的调运,又有助于缓解目的港干货箱的积压状况。但是,在实际操作中会遇到较多问题,船公司