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Background Postoperative C5 palsy is not an uncommon complication in patients who undergo expansive open-door laminoplasty. However, the etiology is unclear and likely multifactorial. Nerve root lesions and spinal cord lesions have been previously proposed theories. Purpose To investigate the anatomical mechanism of postoperative C5 palsy after cervical expansive open-door laminoplasty. Study design A dissection-based study of 8 embalmed human cadavers. Methods The anatomy was studied in 8 whole cervical cadavers (3 females, 5males), prepared with formaldehyde, whose ages at the time of death ranged from 54 to 78 years. Dissection was performed on the intervertebral foramen and spinal canal. In the C3-C7 of the cervical vertebra, the extraforaminal ligaments and the meningovertebral ligaments were observed. The length, width, and thickness of the ligaments were measured with a vernier caliper. After an expansive open-door laminoplasty was performed, the shape of the dural sac was changed, and displacement of the nerve root was observed. In addition, the lengths of the anterior rootlets were measured. This study has been supported by grants from Science and Technology Planning Project of Guangdong Province (CN) (Grant No. 2017B020210010) without potential conflict of interest-associated biases in the text of the paper. Results One hundred seventy-seven extraforaminal ligaments were found to connect the spinal nerve to the surrounding structures. After an expansive open-door laminoplasty was performed, posterior distension of the dural sac, and movement of the spinal cord and nerve root were found. The spinal cord was closely attached to the ligamentum flavum by meningovertebral ligaments. In addition, the length of the C5 intradural rootlets (5.81-10.59 mm) was the shortest among the vulnerable segments. Conclusion Traction on and posterior movement of the extradural roots may be the main pathological mechanism of postoperative C5 palsy when expansive open-door laminoplasty is performed. The meningovertebral ligaments and EFLs might play an important role in the occurrence of postoperative C5 palsy. Clinical Significance This study provides clinicians with a more detailed understanding of the anatomic structure and potential mechanism of C5 palsy. Consideration of the meningovertebral ligaments and the intervertebral foramen may provide new directions for reducing the incidence of this complication.

The prevalence of hepatitis B virus (HBV) infection was an imbalance in different provinces of China. This study aimed to investigate the prevalence of HBV infection and evaluate the prophylactic measures in a public hospital of northeast China over the preceding 13 years. A total of 13,948 patients in 2004 and 15,256 patients in 2017 of Shengjing Hospital of China Medical University were tested of serum HBsAg, HBeAg, HBsAb, HBeAb, and HBcAb levels with Abbott MEIA Kits. In people born before 1992, HBsAg-positive rate was 5.45% and 6.47%; isolated HBsAb positive rate was 14.62% and 21.24%; HBV marker negative rate was 54.27% and 42.77% in 2004 and 2017 survey, respectively. The males had a significant higher HBsAg-positive rate than the females. In people born during 1992-2004, HBsAg positive rate was 0.58% and 0.57%, isolated HBsAb positive rate was 41.47% and 46.57%; and HBV marker negative rate was 51.97% and 46.86% in 2004 and 2017 survey, respectively. Males and females had no difference of HBsAg-positive rate. In children born after 2005, HBsAg positive rate was 0.11%, isolated HBsAb positive rate was 76.68%, and HBV marker negative rate was 18.51% in 2017 survey. No difference of HBsAg-positive rate was found between the genders. A dramatic decrease of HBsAg positive rate and a progressive increase of HBsAb-positive rate were found among people born after 1992 and progressed further in those born after 2005. Immunization of infants and timely birth dose was the key method for prevention of HBV infection. Expanded HB vaccination would be needed for people born before 2005, especially those born between 1992 and 2004.

The quad-tree plus binary-tree (QTBT) partition structures was adopted into the versatile video coding (VVC) standard. In the QTBT partition structure, a dual tree structure can be applied on intra slices where the partitioning structures for luminance and chrominance components are separate. The dual tree structure is efficient for camera captured videos. However, it may be not the case for screen content videos. Therefore, adaptive dual tree structure is proposed in this paper wherein the coding structure of each coding tree unit is switched between separate and joint coding structure to adapt the textures adaptively. The proposed scheme is implemented into the reference software of the VVC standard-VTM. Simulation results report that up to 4.5% BD bitrate saving can achieve on the typical screen content videos when compared to VTM5.

Background and objectivesThe periarticular sacroiliac joint (SIJ) technique has become an important area of focus, and the quartering of the SIJ posterior ligamentous region has been proposed as a way to refine this technique. However, detailed nerve distribution combined with the division of the SIJ posterior ligamentous region is lacking. We aimed to explore the innervation of the SIJ posteriorly based on the quartering of the SIJ posterior ligamentous region.MethodsSixteen SIJs from eight embalmed cadavers were studied. Each SIJ posterior ligamentous region was equally divided into areas 0–3 from top to bottom. The origin, distribution, quantity, transverse diameter, spatial orientation, relation with bony structures, and the number of identifiable terminal nerve branches in each area were examined.ResultsAreas 0–1 were innervated by the lateral branches of the dorsal rami of L4−L5 directly in all specimens. Areas 2–3 were innervated by that of both lumbar and sacral nerves via the posterior sacral network (PSN), with L5 contributing to the PSN in all specimens and L4 in 68.75%. The number of identifiable terminal nerve branches were significantly higher in areas 2–3 than in areas 0–1.ConclusionsThe inferior part of the SIJ posterior ligamentous region seems to be the main source of SIJ-related pain and is innervated by lumbar and sacral nerves via the PSN. However, the superior part directly innervated by lumbar nerves should not be neglected, and further clinical verification is needed.

The joint collaborative team on video coding has been developing an emerging standard for screen content coding (SCC) as an extension of HEVC known as HEVC-SCC. Intrablock copy (IBC) and palette coding are the two powerful coding tools adopted into HEVC-SCC. In this paper, a novel coding tool named inter-palette coding is proposed, which takes the advantages of both IBC and palette coding. With the inter-palette method, a new palette copy mode COPY_INTER can be applied, which enables the index samples to copy the pixels in the prediction block fetched by IBC or motion compensation. Experimental results show that the proposed scheme can achieve 3.15% BD-rate savings under all intra conditions on typical sequences containing “text and graphics with motion” averagely, with almost no complexity penalty.

The Joint Video Exploration Team (JVET) has been developing an emerging standard Versatile Video Coding (VVC), which includes screen contents as one of its requirements. Intra block copy (IBC) and palette coding are the two powerful coding tools for screen content coding. In this paper, a compound palette mode is proposed to exploit the advantages of both IBC and palette coding, which allows samples to be reconstructed by either IBC predictions or palette entries. The proposed method is evaluated with VVC reference software VTM4 on typical sequences containing "text and graphics with motion". Experimental results report significant coding gain that the proposed scheme can achieve 7.80% and 1.03% BD-rate savings under AI conditions on average when compared with VTM4 and the existing palette scheme.

With the rapid development of information technology in geo-engineering, smart management of infrastructure is becoming a trend. According to digitization techniques, integrated construction and maintenance of infrastructure, this paper is aimed to build an automated dynamic monitoring analysis system of braced excavation to realize intelligent management based on Infrastructure Smart Service System (iS3). First, the improved KJHH model is established to be suitable for the specified soft soil area by considering the system stiffness \( EI /\gamma_{w} h_{avg}^{ 4} \) into Bayes back analysis. Second, based on the improved KJHH model, an automated dynamic monitoring analysis system can make visualization of excavation, use Bayesian methodology to update stratum parameters based on remote monitoring data, and make predictions of wall deflection and ground settlement. Finally, the applicability of automated dynamic monitoring analysis system was verified by the foundation project of Qiubi station of Ningbo metro line 3. It can provide a more reliable and effective way for safety analysis and risk pre-warning in the excavation engineering.

By considering the increasing importance of screen contents, the high efficiency video coding (HEVC) standard includes screen content coding as one of its requirements. In this paper, we demonstrate that enabling frame level block searching in HEVC can significantly improve coding efficiency on screen contents. We propose a hash-based block matching scheme for the intra block copy mode and the motion estimation process, which enables frame level block searching in HEVC without changing the HEVC syntaxes. In the proposed scheme, the blocks sharing the same hash values with the current block are selected as prediction candidates. Then the hash-based block selection is employed to select the best candidates. To achieve the best coding efficiency, the rate distortion optimization is further employed to improve the proposed scheme by balancing the coding cost of motion vectors and prediction difference. Compared with HEVC, the proposed scheme achieves 21% and 37% bitrate saving with all intra and low delay configurations with encoding time reduction . Up to 59% bitrate saving can be achieved on sequences with large motions.

Screen content like cartoons, captures of typical computer screens or video with text overlay or news ticker is an important category of video, which needs new techniques beyond the existing video coding techniques. In this paper, we analyze the characteristics of screen content and coding efficiency of HEVC on screen content. We propose a new coding scheme, which adopts a non-transform representation, separating screen content into color component and structure component. Based on the proposed representation, two coding modes are designed for screen content to exploit the directional correlation and non-translational changes in screen video sequences. The proposed scheme is then seamlessly incorporated into the HEVC structure and implemented into HEVC range extension reference software HM9.0. Experimental results show that the proposed scheme achieves up to 52.6% bitrate saving compared with HM9.0. On average, 35.1%, 29.2% and 23.6% bitrate saving are achieved with intra, random-access and low-delay configurations, respectively. The visual quality of the decoded video sequences is also significantly improved by reducing ringing artifacts around sharp edges and reserving the shape of text without blur.

Motion estimation plays an important role in video coding standards, such as H.264/AVC and HEVC. In this paper, we propose a multi-stage hash based motion estimation algorithm for HEVC, which enables hash based motion estimation for natural videos. In the proposed method, the prediction blocks significantly different from the current prediction unit will be eliminated in the motion estimation process. Locality sensitive hashing functions are used to measure the difference between the input block and predicted blocks. The proposed algorithm is implemented into the HM 12.0 software, and the simulation results show that the complexity of motion estimation is significantly reduced with negligible coding performance loss.

Screen contents with complex structure contain random combination of texts, graphics and camera-captured images, which makes them difficult to be compressed efficiently by traditional video codecs. In this paper, we propose a 2-D dictionary based scheme to exploit the repeated patterns on screen content. In the proposed scheme, the current block is predicted from the reconstructed region using a hash-based block searching scheme. A hierarchical two-level hash based searching scheme is designed to find the best matching block for each block. The first-level hash function is used to search the blocks similar to the current block in the constructed 2-D dictionary. The second-level hash function is used to update the 2-D dictionary, which filters out the identical blocks from the blocks found using the first-level hash function. The proposed scheme is incorporated into HEVC framework as an additional mode. Experimental results show that the proposed scheme achieves significantly coding performance improvements on screen contents compared with HEVC.

Computer generated compound images contain not only photographic images but also text and graphics images, which makes it difficult to be efficiently compressed using exiting image and video coding standards. This paper presents a new compound image coding scheme based on the intra coding framework of the upcoming high efficiency video coding (HEVC) standard. The proposed scheme first decomposes the compound image into color components and structure components. Then two-stage prediction scheme is employed to exploit the correlation among structure components, where the first prediction is generated by directional prediction and second prediction is generated by template matching. Experimental results show that the proposed scheme achieves up to 10.2 dB coding gain on compound images compared with HEVC. And on average it achieves 42.2 percent bitrate saving compared with HEVC.

This paper first presents a brief overview of the PBB and the H-VPLS technologies, along with the shortcomings of existing H-VPLS, and then designs the solutions by deploying PBB interoperating with H-VPLS over networks with a MPLS core, which improve the standard H-VPLS.

Introduced in this paper are a technique of fiber optic dual-wavelength pyrometer and its principle, structure and characteristics. It was successfully applied under the hostile environment in hot-blast stoves to measure high-temperature. The efforts to overcome all difficulties, such as pressure, water vapor, and probe bend caused by thermal expansion, are reported in details. The resulting device is reliable, stable and accurate, and has immunity to harmful gas corrosion. The proposed pyrometer has a long lifetime. Therefore, it can replace the conventional thermo-electric-couple for temperature measurement in a blast furnace.

According to the optical electromagnetic theory, this paper demonstrates that we should not apply the usual simplified theoretical formulas of transparent dielectric (such as glass) to design semiconductor (Si) cell antireflection (AR) films. We must consider the macroscopic optical properties of semiconductor itself. We have deduced a strict formula for wide band three-layer AR coatings on semiconductor (Si) cell. By this formula, we can calculate the 'theoretical reflectance' of solar cells at any film thickness and wavelength. We have screened some type of double-layer film that increased the current gain of space solar cell effectively. For outerspace solar cells, it is necessary to have an 'optical matching system,' which is made up several layers of transparent material: AR coatings of silicon, silicon rubber adhesive and anti-radiation cover glass. For the solar cell with 'optical matching system,' we have also formulated its total reflectance Rt as a function of the reflectance Rm from AR film upon silicon, the index of refraction of cover glass ng, the index of refraction of silicon rubber adhesive nj, the transmittance of the upper surface of glass T.Rt has a parabolic type of T.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Screen content refers to image/video generated by electronic devices. Existing state-of-art image/video coding standards don't exploit the anisotropic features. This paper proposes an adaptive LZMA-based coding scheme for screen content to achieve better coding efficiency. Adaptive scanning and directional matching are incorporated into LZMA in our scheme. Both of them exploit the directional correlations in screen content to increase the matching probability of LZMA, and thus achieve better coding performance. Experimental results show that the proposed scheme significantly outperforms existing LZMA-based coding schemes on screen content coding.