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A proximal femoral nail using a helical blade (HB) is commonly utilized to treat proximal femoral fracture but cut through failure of the lag screws is one of the devastating complications following the surgery. While controversial, one of the potential risk factors for cut through failure is poor bone strength which can be predicted by measuring bone mineral density (BMD). In this study, we performed a biomechanical test on the fractured femoral head to validate whether the indirectly measured BMD from the contralateral hip or that measured directly from the retrieved femoral head can elucidate the structural strength of the fractured femoral head and thereby can be used to predict migration of lag screws. Our result showed that directly measured BMD has a significant correlation with the HB migration on the osteoporotic femoral head. However, while the BMDs measured from the contralateral femoral neck or total hip is the most widely used parameter to predict the bone strength of the fractured femur, this may have limited usability to predict HB migration. [ABSTRACT FROM AUTHOR]

Background and Objectives: Anterior capsulotomy is routinely performed in hip arthroscopy to improve joint visualization; however, this can partly or completely disrupt the stabilizing ligaments of the hip. This study aimed to report the effects of conventional and extensive arthroscopic capsulotomies on hip stability. Materials and Methods: Eight freshly frozen cadaveric pelvises were used in this study. The range of motion and translation were measured and compared among different capsular conditions utilized in hip arthroscopy, with a special interest in the iliofemoral ligament (IFL) and zona orbicularis (ZO). The conditions included intact capsule, interportal capsulotomy, T-capsulotomy, complete IFL disruption, and complete IFL and ZO disruption. Internal rotation at three flexion planes (−10°, 0°, and 30°) and external rotation at six flexion planes (−10°, 0°, 30°, 60°, 90°, and 110°) were measured with corresponding femoral head translation distance at the application of 2.5 Nm torque. Results: As compared to an intact capsule, a significant increase in external rotation was observed after interportal capsulotomy from −10° to 60° and after T-capsulotomy from −10° to 110° flexion. A significant translation was observed only with a T-capsulotomy, which ranged from 1.9 to 2.3 mm across the flexion angles. Compared with conventional interportal capsulotomy, disruption of the entire IFL resulted in a significant increase in external rotation in all flexion planes, and significant translation was accompanied by disruption of the ZO. Conclusions: Interportal capsulotomy can result in an increase in range of motion, and T-capsulotomy can lead to significant translation. Partial or complete tears of the IFL and ZO can result in further external rotation and translation. [ABSTRACT FROM AUTHOR]

Content delivery service has become a major traffic load on today's Internet, and this has triggered the interest of ISPs in operating their own content delivery networks (CDNs) to optimize Internet traffic considering both content delivery caching and user-network proximity. ISPs, however, are typically regionally bound or network-domain-wise isolated; hence, their CDN gain is somewhat limited. In order to enhance the gain of ISP CDN services to the level of incumbent global CDNs, a CDN interconnection (CDNI) model is introduced by IETF, where local ISP CDN services can be extended among heterogeneous CDNs across network domains. However, despite the multiple benefits of a CDNI system, it is difficult to apply a CDNI service to the current CDN market due to the platform independence. Hence, we introduced a CDNI gateway model that is standard-capable and platform-independent. With the CDNI gateway model, we design and implement a complete CDNI system and conduct a CDNI service trial with three major ISPs in South Korea. To the best of our knowledge, this is the first CDNI service trial complying with the IETF standard achieved by a multi-ISP collaboration. According to the analysis of experimental results from the service trial, we observe that CDNI can reduce content traffic by about 40 percent at the Internet exchange link compared to a legacy CDN system. [ABSTRACT FROM PUBLISHER]

Background: High-throughput three-dimensional metrology techniques for monitoring in-wafer uniformity (IWU) and in-cell uniformity (ICU) are critical for enhancing the yield of modern semiconductor manufacturing processes. However, owing to physical limitations, current metrology methods are not capable of enabling such measurements. For example, the optical critical dimension technique is not suitable for ICU measurement, because of its large spot size. In addition, it is excessively slow for IWU measurement. Aim: To overcome the aforementioned limitation, we demonstrate a line-scan hyperspectral imaging (LHSI) system, which combines spectroscopy and imaging techniques to provide sufficient information for spectral and spatial resolution, as well as high throughput. Approach: The proposed LHSI system has a 5-μm spatial resolution together with 0.25-nm spectral resolution in the broad-wavelength region covering 350 to 1100 nm. Results: The system enables the simultaneous collection of massive amounts of spectral and spatial information with an extremely large field of view of 13 × 0.6 mm2. Additionally, throughput improvement by a factor of 103 to 104 can be achieved when compared with standard ellipsometry and reflectometry tools. Conclusions: Owing to its high throughput and high spatial and spectral resolutions, the proposed LHSI system has considerable potential to be adopted for high-throughput ICU and IWU measurements of various semiconductor devices used in high-volume manufacturing. [ABSTRACT FROM AUTHOR]