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Over the past decades, the utilization of Li-ion batteries has provided the benefits of high energy and power density and can be used in a variety of applications, including electric vehicles, large-scale energy storage, and the power grid.

The goal of this study was to evaluate the interrelationship between different magnetic resonance (MR) imaging measures and their validity in assessing the severity of acute traumatic spinal cord injury (tSCI) and predicting neurological outcomes.We performed a preoperative multicenter cohort study of 89 patients with acute tSCI and preoperative MR imaging within 24 h after injury. We assessed several MR imaging measures of injury, including axial grade (Brain and Spinal Injury Center [BASIC] score), sagittal grade, length of injury, maximum canal compromise (MCC), and maximum spinal cord compression (MSCC). Principal component analysis (PCA) was applied to evaluate the interrelationship between different MR imaging measures. Spearman correlation and regression analyses were applied to assess injury severity and predict neurological impairment. The severity was assessed by the American Spinal Injury Association Impairment Scale (AIS) at admission, while neurological outcome was defined by AIS grade change at 6 weeks, AIS grade and SCIM score at 1 year after surgery.The PCA identified 2 clusters of MR imaging variables related to 1) measures of intrinsic cord signal abnormality (BASIC score, sagittal grade and length of injury) and 2) measures of extrinsic cord compression (MCC and MSCC). Neurological outcome and injury severity were best accounted for by MR imaging measures of intrinsic cord signal abnormalities, with the BASIC score representing the most accurate predictor of short-term and long-term neurological outcomes.We determined the superior significance of the BASIC score in assessing injury severity, predicting early AIS improvement, AIS grade and SCIM score at 1 year compared with other MR imaging measures.

Aims The morphology of medial malleolar fracture is highly variable and difficult to characterize without 3D reconstruction. There is also no universally accepeted classification system. Thus, we aimed to characterize fracture patterns of the medial malleolus and propose a classification scheme based on 3D CT reconstruction. Methods We retrospectively reviewed 537 consecutive cases of ankle fractures involving the medial malleolus treated in our institution. 3D fracture maps were produced by superimposing all the fracture lines onto a standard template. We sliced fracture fragments and the standard template based on selected sagittal and coronal planes to create 2D fracture maps, where angles α and β were measured. Angles α and β were defined as the acute angles formed by the fracture line and the horizontal line on the selected planes. Results A total of 121 ankle fractures were included. We revealed several important fracture features, such as a high correlation between posterior collicular fractures and posteromedial fragments. Moreover, we generalized the fracture geometry into three recurrent patterns on the coronal view of 3D maps (transverse, vertical, and irregular) and five recurrent patterns on the lateral view (transverse, oblique, vertical, Y-shaped, and irregular). According to the fracture geometry on the coronal and lateral view of 3D maps, we subsequently categorized medial malleolar fractures into six types based on the recurrent patterns: anterior collicular fracture (27 type I, 22.3%), posterior collicular fracture (12 type II, 9.9%), concurrent fracture of anterior and posterior colliculus (16 type III, 13.2%), and supra-intercollicular groove fracture (66 type IV, 54.5%). Therewere three variants of type IV fractures: transverse (type IVa), vertical (type IVb), and comminuted fracture (type IVc). The angles α and β varied accordingly. Conclusion Our findings yield insight into the characteristics and recurrent patterns of medial malleolar fractures. The proposed classification system is helpful in understanding injury mechanisms and guiding diagnosis, as well as surgical strategies. Cite this article: Bone Joint J 2021;103-B(5):931–938.

Purpose: We aimed to construct a nonlinear regression model through Extreme Gradient Boost (XGBoost) to predict functional outcome 1 year after surgical decompression for patients with acute spinal cord injury (SCI).Methods: We prospectively enrolled 249 patients with acute SCI from 5 primary orthopedic centers from June 1, 2016, to June 1, 2020. We identified a total of 6 predictors with three aspects: 1) clinical characteristics, including age, American Spinal Injury Association (ASIA) Impairment Scale (AIS) at admission, level of injury and baseline ASIA motor score (AMS); 2) MR imaging, mainly including Brain and Spinal Injury Center (BASIC) score; 3) surgical timing, specifically comparing whether surgical decompression was received within 24 hours or not. We assessed the SCIM score at 1 year after the operation as the functional outcome index. XGBoost was used to build a nonlinear regression prediction model through the method of boosting integrated learning.Results: We successfully constructed a nonlinear regression prediction model through XGBoost and verified the credibility. The average absolute value of the difference between the predicted value and the actual value is 3.72 (t=1.29, P=0.203), ranging from 0 to 8.44. AMS and age ranked first and second in predicting the functional outcome.Conclusion: We verified the feasibility of using XGBoost to construct a nonlinear regression prediction model for the functional outcome of patients with acute SCI, and we found that age and AMS play the most important role in predicting the functional outcome.Trial registration: ClinicalTrials.gov identifier: NCT03103516.

Purpose We designed a prospective cohort study based on magnetic resonance angiography (MRA) to identify whether the degree of Kummell disease (KD) vertebral artery occlusion is more severe than that of simple vertebral compression fractures. Methods We enrolled elderly patients with VCFs who met the established criteria from January 2019. MRA was used to determine the degree of vertebral artery occlusion. We defined the lesion segmental occlusion rate (LSOR) as the sum of the ischemic values of the bilateral vertebral segmental arteries (0 means expedite, 1 means stenosis, 2 means occlusion; range from 0–4). The average LSOR is the sum of LSORs divided by the number of vertebrae. Follow-up outcomes included VAS and ODI scores after surgery. X-rays were re-examined at 1 year after surgery to determine whether the vertebral body had recollapsed. Results 25 cases of KD segments and 37 cases of non-KD segments were included. The average LSOR in KD segments was significantly higher than that in non-KD segments (1.44 vs 0.32, P

Background: Hallux valgus is one of the most common foot deformities. Surgical treatment is the optimal choice for moderate to severe hallux valgus deformity. Rotation scarf with Akin osteotomy has become increasingly popular. The purpose of our study is to evaluate the long-term outcomes of rotation scarf with Akin osteotomy on severe hallux valgus. Methods: We conducted a retrospective study of patients with hallux valgus who underwent surgery using rotation scarf with Akin osteotomy in our hospital between June 2014 and January 2020. Anteroposterior and lateral weightbearing X-ray were performed before and after the operation. The parameters evaluated include (1) the hallux valgus angle (HVA), (2) intermetatarsal angle (IMA), (3) distal metatarsal articular angle (DMAA) and (4) tibial sesamoid position (TSP). A visual analog scale (VAS) was used to evaluate the pain level before and at the last follow-up after the operation. American Orthopaedic Foot & Ankle Society (AOFAS) Forefoot Score were assessed before and at the last follow-up after the operation. Patient satisfaction assessment was also conducted at the time. Results: A total of 42 patients with 50 feet met our inclusion criteria. Average age at the time of surgery was 61 ± 9 years. Follow-up data were obtained in all 42 patients. The average follow-up time was 47.4 ± 20 months. All radiological parameteres including HVA, IMA, DMAA and TSP had statistically significant improvement (p < 0.001). The VAS score and AOFAS score was also statistically significant before operation and at the last follow-up after the operation (p < 0.001). There are 41 (82%) feet in patients were very satisfied or satisfied. Conclusion: Rotation scarf with Akin osteotomy is demonstrated to be safe, effective, and feasible for correcting severe hallux valgus. It can obtain good long-term correction with a low incidence of recurrence and metatarsalgia. Postoperative satisfaction and functional recovery of patients are significantly improved.

The morphology of medial malleolar fracture is highly variable and difficult to characterize without 3D reconstruction. There is also no universally accepeted classification system. Thus, we aimed to characterize fracture patterns of the medial malleolus and propose a classification scheme based on 3D CT reconstruction.We retrospectively reviewed 537 consecutive cases of ankle fractures involving the medial malleolus treated in our institution. 3D fracture maps were produced by superimposing all the fracture lines onto a standard template. We sliced fracture fragments and the standard template based on selected sagittal and coronal planes to create 2D fracture maps, where angles α and β were measured. Angles α and β were defined as the acute angles formed by the fracture line and the horizontal line on the selected planes.A total of 121 ankle fractures were included. We revealed several important fracture features, such as a high correlation between posterior collicular fractures and posteromedial fragments. Moreover, we generalized the fracture geometry into three recurrent patterns on the coronal view of 3D maps (transverse, vertical, and irregular) and five recurrent patterns on the lateral view (transverse, oblique, vertical, Y-shaped, and irregular). According to the fracture geometry on the coronal and lateral view of 3D maps, we subsequently categorized medial malleolar fractures into six types based on the recurrent patterns: anterior collicular fracture (27 type I, 22.3%), posterior collicular fracture (12 type II, 9.9%), concurrent fracture of anterior and posterior colliculus (16 type III, 13.2%), and supra-intercollicular groove fracture (66 type IV, 54.5%). Therewere three variants of type IV fractures: transverse (type IVa), vertical (type IVb), and comminuted fracture (type IVc). The angles α and β varied accordingly.Our findings yield insight into the characteristics and recurrent patterns of medial malleolar fractures. The proposed classification system is helpful in understanding injury mechanisms and guiding diagnosis, as well as surgical strategies. Cite this article

An intra-articular impacted fragment (IAIF) could lead to articular incongruity and malreduction in ankle fractures with posterior malleolar fractures (PMFs). No studies have been conducted to determine whether the presence of IAIF affects the outcome of ankle fractures with PMF. The aim of our retrospective study was to evaluate the effect of IAIF on postoperative outcomes in PMF and analyze the relationship between area of IAIF and outcomes. We conducted a retrospective study of patients with a posterior malleolar fractures between June 2012 and January 2019 with a minimum follow-up of 2 years. Results of the Olerud–Molander ankle score (OMAS), EuroQol-5D (EQ-5D) index, EQ-5D visual analog scale (VAS), AOFAS (American orthopedic foot and ankle society ankle-hindfoot scale), visual analog scale (VAS) pain score and overall patient satisfaction scale were recorded. Outcomes of the PMF with IAIF group and PMF without IAIF group were compared. Sub-group analysis was given emphasis on the AIAIF > 40 mm2 group and AIAIF 1, ≤ 1), the differences werestatistically significant between the two groups (P = 0.044). The risk of articular malreduction was higher in the PMF with IAIF group than in the PMF without IAIF group (P = 0.035). Osteoarthritis grade (> 1, ≤ 1) was closely related to articular malreduction (P 40 mm2 group and 35 patients in the AIAIF 1, ≤ 1; P = 0.027), EQ-5D VAS score (P = 0.031), and AOFAS score (P = 0.047) between the subgroups. The incidence of IAIF is associated with the area of the posterior malleolar fragment. Articular malreduction can lead to post-traumatic osteoarthritis, while IAIF is an important element for the quality of reduction, which is more likely to lead to articular malreduction. IAIF should be reduced if AIAIF is over 40 mm2. Otherwise, the patient will suffer a poor prognosis and post-traumatic osteoarthritis. Therefore, ankle fractures with PMF should undergo a CT scan preoperatively in order for providers to optimal treatment protocols. Level III.

Background: The morphology and classification of posterior malleolus (PM) fractures remain controversial. An increasing number of studies have found that merely focusing on the fragment size does not lead to a satisfactory prognosis. This study aimed to demonstrate the fracture line and comminution zones of PM fractures using computed tomography (CT), in order to provide insights into the injury mechanism of PM fractures. Methods: We retrospectively reviewed the data of 95 patients with PM fractures between 2013 and 2018 at a level 1 trauma center. The CT data of the PM of the patients were reconstructed using software. Images of all patients were superimposed together, and drawn as a heat map of the fragments and line distributions of PM fractures. Results: Our study included 66 type I, 19 type II, and 10 type III PM fractures according to the classification of Haraguchi. In the single-fragment fracture group, the fracture lines were mainly concentrated in the posterolateral tibial tubercle area (Volkmann’s tubercle) and a larger tubercle area involving the tibialis posterior groove. In the multifragment fracture group, there were 10 (43.5%) patients with a 2-fragment pattern and 13 (56.5%) patients with a compressive-fragment pattern. Conclusion: According to the fracture map and previous studies on the syndesmosis, our study provides a different understanding of the pathomechanisms of ankle injuries compared with previous classifications of PM fractures. Level of Evidence: Level III, retrospective study.

As a chemical detection technology for analysis of in-situ, real time and multiple materials, Laser Raman Spectroscopy is competent to take quantitative research for ingredients in ocean environment, and achieve long-term in-situ supervision of acid radical ionic concentration in seawater. Due to the inevitable interference in the actual detection environment, the spectral data often contains some outliers, the existence of which has a significant impact on the performance of the quantitative analysis model. In order to remove the outliers accurately in the in-situ detection and online analysis, the MMD algorithm was combined with the PLS quantitative analysis model (PLS-MMD model) to detect and remove the outliers in the calibration set. It was demonstrated that the PLS-MMD method can effectively eliminate the abnormal spectra in the calibration data. After removing outliers the accuracy of the measured seawater sample concentration was improved with the relative error decreasing from 1.468% to 1.160%. Correspondingly, the prediction stability of in-situ seawater is also improved.

Panax notoginseng(P.notoginseng), also known as Tianqi in Chinese, is a rare medicinal herb. Panax notoginseng with different quality grades have distinct variance of medicinal values. In this paper, the near-infrared spectroscopy (NIRs) measurement technology is used to collect the spectral information of different grades. The quality identification model of Panax notoginsen is established by multi-classification correlation vector machine (mRVM). And three dimensionality reduction methods, the competitive adaptive reweighted algorithm (CARS) and the firefly algorithm (FA) and successive projections algorithm (SPA), are used to simplify the mRVM model. The results show that FA-mRVM, CARS-mRVM and SPA-mRVM can eliminate a large number of feature variables and filter out the effective feature variables. While FA-mRVM has better performance, with less numbers of feature variables and the highest accuracy. The correct identification rate, root mean square error and average cross-entropy error of the correction set and the prediction set are 100%, 0.0048, 0.0143 and 100%, 0.0046, 0.0141, respectively. Hence, NIRS combined with mRVM can be a useful, rapid, and nondestructive tool to discriminate quality grade of Panax notoginseng.

Nowadays, internet is becoming a suitable way of accessing the databases. Such data are exposed to various types of attack with the aim to confuse the ownership proofing or the content protection. In this paper, we propose a new approach based on fragile zero watermarking for the authentication of numeric relational data. Contrary to some previous databases watermarking techniques which cause some distortions in the original database and may not preserve the data usability constraints, our approach simply seeks to generate the watermark from the original database. First, the adopted method partitions the database relation into independent square matrix groups. Then, group-based watermarks are securely generated and registered in a trusted third party. The integrity verification is performed by computing the determinant and the diagonal’s minor for each group. As a result, tampering can be localized up to attribute group level. Theoretical and experimental results demonstrate that the proposed technique is resilient against tuples insertion, tuples deletion, and attributes values modification attacks. Furthermore, comparison with recent related effort shows that our scheme performs better in detecting multifaceted attacks.