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Abstract Background The purpose of this study was to find the factors influencing successful bone union for isolated subtalar arthrodesis in posttraumatic subtalar arthritis following calcaneal fracture. Material and methods We retrospectively analyzed the rate of successful bone union of 119 cases of isolated subtalar arthrodesis for posttraumatic subtalar arthritis performed at five university hospitals between January 2010 and December 2019. Multivariate logistic regression analysis was used to find the factors associated with successful bone union. Successful bone union was defined as resolution of hindfoot pain with the presence of osseous trabecular bridging involving more than 50% of the posterior facet within 6 months postoperatively. Results There were 77 (64.7%) cases of successful bone union, 11 (9.2%) cases of delayed union, 8 (6.7%) cases of questionable union, and 23 (19.3%) cases of nonunion. Use of fully threaded screws was 5.90 times [odds ratio (OR) = 5.90, 95% confidence interval (CI) = 1.42–24.49, p = 0.02] more likely to achieve successful bone union compared to the use of partially threaded screws. Use of two parallel screws or the two divergent screws were 3.71 times (OR = 3.71, 95% CI = 1.05–13.14, p = 0.04) and 4.65 times (OR = 4.65, 95% CI = 1.23–17.53, p = 0.02) more likely to achieve successful bone union compared to the use of a single screw. Use of cancellous autograft or structural autograft was 4.72 times (OR = 4.72, 95% CI = 1.17–19.06, p = 0.03) and 7.12 times (OR = 7.12, 95% CI = 1.46–34.68, p = 0.02) more likely to achieve successful bone union compared to no graft use. Conclusion Use of fully threaded screws, autograft, and two screws compared to a single screw were the factors associated with successful bone union within six postoperative months after subtalar arthrodesis for the posttraumatic arthritis.

Accurate battery state-of-charge (SOC) estimation is important for the efficient and reliable operation of battery application systems. The extended Kalman filter (EKF), which is based on the battery model, is widely used as a real-time SOC estimation algorithm; furthermore, its accuracy depends on the model accuracy. However, the conventional EKF uses one value for each battery parameter ( $R_{i}$ , $R_{d}$ and $C_{d}$ ) regardless of the SOC, even though their values change according to the SOC. To address this problem, this study proposes an improved EKF that applies battery parameters that change according to the SOC of a battery model. In the proposed method, the entire SOC was divided into several sections considering the deviation of the parameter values according to the SOC. Subsequently, the average values for each SOC Section were calculated, and the values of the battery parameters were updated with the average values according to the SOC. To verify the performance of the proposed EKF, the parameters of commercial Li-ion batteries were extracted with dis-charge currents of 1C- and 2C-rates at ambient temperatures of 0 °C, 25 °C, and 45 °C, and MATLAB simulations were performed. Compared to the conventional EKF, the proposed EKF estimated the SOC more accurately under all the simulation conditions. Compared to the conventional EKF, the maximum reduced root-mean-square error and maximum error of the proposed method were 49.37% and 56.41%, respectively.

Objective To compare the parameters associated with the normal ankle syndesmosis between the hindfoot alignment view (HAV) and anteroposterior (AP) view and determine which view is more accurate for comparing the left and right ankles. Methods This study involved 61 subjects without syndesmosis injury who had radiographs of both ankles. The tibiofibular clear space (TFCS), tibiofibular overlap (TFO), and medial clear space (MCS) were measured in each view. Intraclass correlation coefficients were used to assess the agreement between the two ankles. Difference ratios for the measured parameters between the ankles were also compared. Results The agreement for TFCS showed wide disparity between the two ankles (AP view, 0.576; HAV, 0.858). The highest degree of agreement was seen for TFO (AP view, 0.733; HAV, 0.926). The agreement for MCS was low in both groups. The mean difference ratio for TFCS was also lower in the HAV group (9.9%) than in the AP view group (16.4%); a similar result was observed for TFO (16.4% vs. 25.8%). Conclusions For evaluation of the syndesmosis, use of the HAV showed increased accuracy and few measurement errors when comparing the left and right ankles relative to use of the AP view.

Abstract High strength SiC whisker-reinforced Ti3SiC2 composites (SiCw/Ti3SiC2) with an improved thermal conductivity and mechanical properties were fabricated by spark plasma sintering. The bending strength of 10 wt% SiCw/Ti3SiC2 was 635 MPa, which was approximately 50% higher than that of the monolithic Ti3SiC2 (428 MPa). The Vickers hardness and thermal conductivity (k) also increased by 36% and 25%, respectively, from the monolithic Ti3SiC2 by the incorporation of 10 wt% SiCw. This remarkable improvement both in mechanical and thermal properties was attributed to the fine-grained uniform composite microstructure along with the effects of incorporated SiCw. The SiCw/Ti3SiC2 can be a feasible candidate for the in-core structural application in nuclear reactors due to the excellent mechanical and thermal properties.

Nowadays, the steady-state somatosensory evoked potential (SSSEP)-based brain-computer interfaces (BCIs) has been developed for improving the quality of daily life for people with physical disabilities. However, due to its poor performance of recognizing selective attention tasks and inattention(rest)-state, the SSSEP-based BCI has not been widely used for practical interfaces. In this paper, we propose a mutual information-based spatio-spectral feature selection method for recognizing selective attention tasks and inattention(rest)-state using dry electrodes considering a real-life application, when vibration stimuli were applied to both index fingers. In our methods, the filter-bank common spatial pattern (FBCSP) was used for extracting spatio-spectral features of the SSSEP. Then, discriminative features were selected using a mutual information-based best individual feature (MIBIF) algorithm. The regularized linear discriminant analysis (RLDA) used as the classifier. The feasibility of the proposed method was demonstrated through eight healthy subjects using the vibration stimuli induced SSSEP with spatially clear and distinguishable patterns for SSSEP-based BCI. From our study, the proposed method showed the best classification accuracy with a kappa value of 0.35±0.17. Furthermore, based on the ANOVA with posthoc tests, the proposed method showed significantly higher accuracy as 57.9% in decoding three classes (p -value

Automated driving technologies have advanced remarkably and are expected to be a part of our lives soon. Because automated driving technology does not require a driver, a significant change in future mobility services is expected. Automated driving technology is closely related to the development of public transit services as it can significantly reduce driver labor costs and provide a more comfortable in-vehicle environment. In particular, the preference for automated mobility-on-demand services that can respond in real time to the dynamic demand through automated driving technology is growing. Previous studies have compared passengers’ preferences for automated mobility-on-demand services and other transportation modes and proposed a way to enable more passengers to use automated mobility-on-demand services. However, as the number of pilot operations increases, future research will focus on ways to improve competitiveness among automated mobility-on-demand services. This study conducts a passenger preference survey based on the characteristics of automated mobility-on-demand services. In particular, changes in the in-vehicle environment and seat selection system, which differ from existing mobility-on-demand services due to automated driving technology, are investigated. The latent class modeling approach is used to classify passengers based on stated preference data collected from the survey. The estimation results show that vehicle type and seat choice system have a significant impact on passengers’ preference for automated mobility-on-demand services. In addition, considering that a high percentage of passengers do not prefer to improve autonomy in seat reservation and the in-vehicle environment, this study suggests that cost-consuming service improvement strategies are not always appropriate.

Deep learning approaches are widely employed for forecasting short-term travel demand to respond to real-time demand. Although it is critical for demand forecasting to be evenly distributed in the spatial and temporal views to support real-time mobility service operations, in related studies, the predictive performance of models has been evaluated only in terms of aggregated errors. Therefore, the present study was conducted to investigate the distribution of errors to explore spatiotemporal correlations. Six deep learning models with the same architecture, except for the base module, consisting of three stacked layers, were constructed. These models were used to forecast demands for a station-based bike-sharing service in Seoul, South Korea. To attain our goals, global and local Moran’s I of the errors was introduced to evaluate the spatial and temporal performances of the deep learning approaches. The results showed that the model with convolutional long short-term memory layers, which are effective at predicting spatiotemporal data, outperformed the other models in terms of aggregated performance. However, the global Moran’s I of the errors in the model reflects spatial dependency over the regions. This suggests that the best predictive performance of the model does not necessarily imply that it performs well in demand forecasting in all regions. Furthermore, cluster and outlier analyses of the errors indicated that excessive or insufficient predictions were clustered or dispersed throughout the regions. These results can be used to enhance the model by introducing the spatial correlation index into the loss function or by incorporating additional features for handling spatial correlations.

Unintended acceleration car accident which is hard to be regarded as human errors is examined. We investigated the accident car to determine the cause upon being requested to investigate by the police. From the car black box, we could narrow down the reason of the acceleration. As one of the causes of unintended acceleration we assumed that the restoration failure of the pedal interfered with by improper use of a floor mat and could reconstruct this. We discussed the acceleration values ​​of the accident vehicle and paid attention to the floor mat used in it. The results indicate that the negligible physical interference in the accelerator linkage could cause a devastating accident.

Category: Trauma; Ankle Introduction/Purpose: Isolated lateral malleolus fracture is one of the most common fractures. However, there is controversy regarding the rehabilitation protocols used after surgery. In particular, the initiation point for the weight bearing has not been standardized. In the present study, we investigated the prognostic difference between the immediate and delayed weight bearing on isolated lateral malleolus fractures. Methods: Retrospectively, the medical records of matched 50 and 41patients in the immediate and delayed weight-bearing groups were reviewed. All patients were treated with open reduction and internal fixation using an anatomical locking compression plate. In the immediate weight-bearing group (IWB), tolerable weight bearing (i.e., that can be endured immediately after surgery with crutches) was permitted. In the delayed weight-bearing group (DWB), weight bearing was completely restricted for 4 weeks after surgery. Ankle motion exercise were permitted in both groups since postoperative day. Radiographic assessment data and the clinical outcomes were reviewed. Results: There were no significant differences noted in the radiographic assessments and complications between the two groups. Significant differences of shortening the return to work and hospital stays of IWB rehabilitation protocol were confirmed(5.7 vs. 8.0 days, 6.0 vs. 8.0 days in the IBW and DWB groups, respectively). In FAOS, there was a significant difference in the sport factor evaluated at postoperative 3 months(75.5 vs 68.5, respectively). Conclusion: There were no significant differences between the two groups in the postoperative radiological outcome and complications. And benefits of shortening the return to work and hospital stays of IWB rehabilitation protocol were confirmed. Conclusively, immediate weight bearing is recommended in patients with isolated lateral malleolus fracture, following anatomical reduction and firm fixation through surgery.

Category: Ankle; Sports; Trauma Introduction/Purpose: There are numerous studies recommending fibular groove deepening in the surgical treatment of peroneal tendon dislocation; however, there are some disadvantages to fibular groove deepening procedures. In this study, we evaluated the results of anatomic reattachment of the peroneal retinaculum without fibular groove deepening as a treatment for traumatic peroneal tendon dislocation. Methods: Thirty six patients with recurrent peroneal tendon dislocation, who underwent retinaculum repair without a fibular groove deepening procedure performed by two surgeons between March 2004 and March 2017, were enrolled in this study. Resubluxation of tendon, pain on inversion and eversion power of the ankle were monitored. The range of motion of inversion and eversion were measured and then compared to that of the contralateral side. AOFAS, VAS, FFI scores were obtained for all patients preoperatively and at the final follow-up. Postoperative complications such as infection, sural nerve injury, and recurrence were monitored. Results: Thirty four patients fully recovered without resubluxation of tendon. Two patients were injured again while playing soccer 6 months after the surgery and fast running 20 months after the surgery respectively. One patient had sural nerve injury. But the symptom was relieved at 6 months after the surgery. None of the patients had weakness of evertor. None of the patients had limited ankle motion. Mean AOFAS, VAS, FFI score improved significantly. Conclusion: In conclusion, for the treatment of recurrent dislocation of the peroneal tendon reattachment of the superior retinaculum only without groove deepening followed by proper rehabilitation is sufficient.

Neuroblastoma is a malignant tumor usually occurring in children, which most commonly develops in the abdomen. Primary cervical neuroblastoma has rarely been reported. We present a case of primary retropharyngeal neuroblastoma with an ipsilateral lymph node metastasis, manifesting as a growing neck mass in the retropharyngeal space, in an 11-month old infant.

Mesenteric fibromatosis is a rare benign fibroblastic tumor; moreover, cases that occur in the mesocolon are even rarer. In some cases, mesenteric fibromatosis is difficult to differentiate from a malignant tumor that shows an infiltrative growth pattern or forms intussusception similar to lymphoma or adenocarcinoma. In this study, we reported a case of mesenteric fibromatosis represented as a colo-colic type intussusception adjacent to the ascending colon mimicking malignant tumors such as lymphoma or adenocarcinoma.

Traditionally, adult intussusception has required a bowel resection because of the malignancy risk. A patient with anorexia, weight loss, and abdominal pain visited our clinic. A physical exam and imaging study revealed no acute peritoneal signs. A colonoscopy for biopsy and bowel reduction was attempted. The tissue sample was consistent with intestinal tuberculosis. We report intestinal tuberculosis complicating intussusception which was treated without surgical intervention.

In this paper, an innovative modeling approach for Li-ion battery packs is proposed by considering intrinsic cell unbalances and packaging elements. The proposed modeling method shows that the accurate battery pack model can be achieved if the overall influences of intrinsic cell unbalances and packaging elements are taken account. Concurrently, the proposed method takes a practical model structure, resulting in the reduction of computational burden in a battery management system. Furthermore, because the proposed method utilizes cell information without a manufactured battery pack, it can be helpful to design optimal battery packs. The proposed method is verified through simulation and experimental results of the Li-ion battery pack along with the battery cycler. In three test profiles, the mean absolute percentage errors and root mean square errors of the proposed pack model do not exceed 0.5% and 0.07 V, respectively.

Objective : To evaluate the effectiveness and long-term outcome predictors of percutaneous sacroplasty (PSP). Methods : This single-center study assessed 40 patients with sacral insufficiency fractures using the short-axis technique under C-arm flat-panel detector computed tomography (CT). Two radiologists reviewed the patients’ magnetic resonance and CT images to obtain imaging findings before PSP and determine technical success, respectively. The short-term outcomes were visual analog scale score changes and opioid usage reductions. Long-term outcomes were determined using telephone interviews and the North American Spine Society (NASS) patient-satisfaction index at least one year after PSP. Results : Technical success was achieved without any significant complications in 39 patients (97.5%). Telephone interviews were possible with 12 patients and failed in 10 patients; death was confirmed in 18 patients. Fifteen patients (50%) re-visited the hospital and received conservative treatment, including spinal injections. Nine patients reported positive satisfaction (NASS patientsatisfaction index 1 or 2), while the negative satisfaction group (NASS patient-satisfaction index 3 or 4, n=3) showed a higher incidence of compression fractures at the thoracolumbar spine level (66.7% vs. 22.2%) and previous spinal injection history (66.7% vs. 33.3%). The poor response group also showed higher incidences of facet joint arthrosis (100% vs. 55.6%), central canal stenosis (100% vs. 22.2%), neural foraminal stenosis (33.3% vs. 22.2%), scoliosis (100% vs. 33.3%), and sagittal malalignment (100% vs. 44.4%). Conclusion : PSP was effective for sacral insufficiency fractures and showed good long-term outcomes. Combined compression fractures in the thoracolumbar spine and degenerative lumbar pathologies could be possible poor outcome predictors. [ABSTRACT FROM AUTHOR]

In this study, HIV-1 Rev response element (RRE) RNA was detected via an Au-coated vertical silicon nanowire electrode array (VSNEA). The VSNEA was fabricated by combining bottom-up and top-down approaches and then immobilized by artificial peptides for the recognition of HIV-1 RRE. Differential pulse voltammetry (DPV) analysis was used to measure the electrochemical response of the peptide-immobilized VSNEA to the concentration and types of HIV-1 RRE RNA. DPV peaks showed linearity to the concentration of RNA with a detection limit down to 1.513 fM. It also showed the clear different peaks to the mutated HIV-1 RRE RNA. The high sensitivity and selectivity of VSNEA for the detection of HIV-1 RRE RNA may be attributed to the high surface-to-volume ratio and total overlap diffusion mode of ions of the one-dimensional nanowire electrodes. [ABSTRACT FROM AUTHOR]

Mesenteric fibromatosis is a rare benign fibroblastic tumor; moreover, cases that occur in the mesocolon are even rarer. In some cases, mesenteric fibromatosis is difficult to differentiate from a malignant tumor that shows an infiltrative growth pattern or forms intussusception similar to lymphoma or adenocarcinoma. In this study, we reported a case of mesenteric fibromatosis represented as a colo-colic type intussusception adjacent to the ascending colon mimicking malignant tumors such as lymphoma or adenocarcinoma. [ABSTRACT FROM AUTHOR]

This letter looks at the physics behind sensory data by identifying the parameters that govern the physical system and estimating them from sensory observations. We extend Takens's delay-embedding theorem to the dynamical systems controlled by parameters. An embedding of the product space of the phase and the parameter spaces of the dynamical system can be obtained by the delay-embedding map, provided that the parameter of the dynamical system changes slowly. The reconstruction error is bounded for slowly varying parameters. A manifold learning technique is applied to the embedding obtained to extract a low-dimensional global coordinate system representing the product space. The phase space of the deterministic dynamics can be contracted by using the adjacency relationship in time, which enables recovery of only the parameter space. As examples, the manifolds of synthetic and real-world vowels with time-varying fundamental frequency (F0) are analyzed, and the F0 contours are extracted by an unsupervised algorithm. Experimental results show that the proposed method leads to robust performance under various noise conditions and rapid changes of F0 compared with the current state-of-the-art F0 estimation algorithms. [ABSTRACT FROM AUTHOR]

Transmission control protocols have to overcome common problems in wireless networks. TCP employing both packet loss discrimination mechanism and available bandwidth estimation algorithm, known as the good existing solution, shows significant performance enhancement in wireless networks. For instance, TCP New Jersey which exhibits high throughput in wireless networks intends to improve TCP performance by using available bandwidth estimation and congestion warning. Even though it achieves 17% and 85% improvements in terms of goodput over TCP Westwood and TCP Reno, respectively, we further improve it by exploring maximized available bandwidth estimation, handling bit-error-rate error recovery, and effective adjustment of sending rate for retransmission timeout. Hence, we propose TCP NJ+, showing that for up to 5% packet loss rate, it outperforms other TCP variants by 19% to 104% in terms of goodput when the network is in bi-directional background traffic. [ABSTRACT FROM AUTHOR]

Background: Nonnegative matrix factorization (NMF) is a feature extraction method that has the property of intuitive part-based representation of the original features. This unique ability makes NMF a potentially promising method for biological sequence analysis. Here, we apply NMF to fold recognition and remote homolog detection problems. Recent studies have shown that combining support vector machines (SVM) with profile-profile alignments improves performance of fold recognition and remote homolog detection remarkably. However, it is not clear which parts of sequences are essential for the performance improvement. Results: The performance of fold recognition and remote homolog detection using NMF features is compared to that of the unmodified profile-profile alignment (PPA) features by estimating Receiver Operating Characteristic (ROC) scores. The overall performance is noticeably improved. For fold recognition at the fold level, SVM with NMF features recognize 30% of homolog proteins at > 0.99 ROC scores, while original PPA feature, HHsearch, and PSI-BLAST recognize almost none. For detecting remote homologs that are related at the superfamily level, NMF features also achieve higher performance than the original PPA features. At > 0.90 ROC50 scores, 25% of proteins with NMF features correctly detects remotely related proteins, whereas using original PPA features only 1% of proteins detect remote homologs. In addition, we investigate the effect of number of positive training examples and the number of basis vectors on performance improvement. We also analyze the ability of NMF to extract essential features by comparing NMF basis vectors with functionally important sites and structurally conserved regions of proteins. The results show that NMF basis vectors have significant overlap with functional sites from PROSITE and with structurally conserved regions from the multiple structural alignments generated by MUSTANG. The correlation between NMF basis vectors and biologically essential parts of proteins supports our conjecture that NMF basis vectors can explicitly represent important sites of proteins. Conclusion: The present work demonstrates that applying NMF to profile-profile alignments can reveal essential features of proteins and that these features significantly improve the performance of fold recognition and remote homolog detection. [ABSTRACT FROM AUTHOR]

A high-performance fundamental frequency estimator inspired by the human auditory system is presented, it uses a cubic-root transform and contrast enhancement on the spectral domain to enhance weak harmonics and suppress noise. The proposed weighted unbiasing process reduces multiple or submultiple pitch errors efficiently. Evaluation is performed under the presence of white noise, babble noise, and telephone channel distortion. The results show that the proposed method performs equivalent to or better than previous state-of-the-art methods in the majority of the noise and channel conditions. [ABSTRACT FROM AUTHOR]

R-curve behavior of Si3N4-BN composites and monolithic Si3N4 for comparison was investigated. Si3N4-BN composites showed a slowly rising R-curve behavior in contrast with a steep R-curve of monolithic Si3N4. BN platelets in the composites seem to decrease the crack bridging effects of rod-shaped Si3N4 grains for small cracks, but enhanced the toughness for long cracks as they increased the crack bridging scale. Therefore, fracture toughness of the composites was relatively low for the small cracks, but it increased significantly to ∼8 MPa·m½ when the crack grew longer than 700 μm, becoming even higher than that of the monolithic Si3N4. [ABSTRACT FROM AUTHOR]

This paper presents a new vehicle model to estimate vehicle yaw rate. This model is improved from the conventional two-degree-of-freedom vehicle model, so-called bicycle model, taking nonlinear effects into account. This model is still linear, although nonlinear effects are included. Nonlinear effects are expressed as a time variant system. These nonlinear effects are: (i) tyre nonlinearity; (ii) lateral load transfer during cornering; (iii) variable gear ratio with respect to vehicle velocity. Kalman filter equation was derived from the proposed model. Estimation results are validated with the experimental results. [ABSTRACT FROM AUTHOR]

Presents a modelling method to analyze the frequency characteristics of a suspension system. Employment of the superelement and lumped methods; Incorporation of the methods with a multibidy dynamics formulation; Results of the computer simulation and test.