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Multilevel lumbar fusion with posterior pedicle screw fixation is a widely performed surgical procedure for the management of adult spinal deformity. However, there has not been a comprehensive biomechanical study on the different types of fusion levels in terms of stability and possible complications. We aimed to investigate the biomechanical properties of multilevel lumbar fusion according to different types of upper and lower fusion levels. Six different types of fusions were performed using three-dimensional finite element models. Type A and B referred to the group of which upper fusion level was L1 and T10, respectively. Subtype 1, 2, and 3 referred to the group of which lower fusion level was L5, S1, and ilium, respectively (A1, L1-L5; A2, L1-S1; A3, L1-ilium; B1, T10-L5; B2, T10-S1; B3, T10-ilium). Flexion, extension, axial rotation, and lateral bending moments were applied, and the risk of screw loosening and failure and adjacent segment degeneration (ASD) was analyzed. Stress at the bone-screw interface of type B3 was lowest in overall motions. The risk of screw failure showed increasing pattern as the upper and lower levels extended in all motions. Proximal range of motion (ROM) increased as the lower fusion level changed from L5 to S1 and the ilium. For axial rotation, type B3 showed higher proximal ROM (16.2°) than type A3 (11.8°). In multilevel lumbar fusion surgery for adult spinal deformity, adding iliac screws and increasing the fusion level to T10-ilium may lower the risk of screw loosening. In terms of screw failure and proximal ASD, however, T10-ilium fusion has a higher potential risk compared with other fusion types. These results will contribute for surgeons to provide adequate patient education regarding screw failure and proximal ASD, when performing multilevel lumbar fusion.

In this paper, to improve the slow processing speed of the rule-based visible and NIR (near-infrared) image synthesis method, we present a fast image fusion method using DenseFuse, one of the CNN (convolutional neural network)-based image synthesis methods. The proposed method applies a raster scan algorithm to secure visible and NIR datasets for effective learning and presents a dataset classification method using luminance and variance. Additionally, in this paper, a method for synthesizing a feature map in a fusion layer is presented and compared with the method for synthesizing a feature map in other fusion layers. The proposed method learns the superior image quality of the rule-based image synthesis method and shows a clear synthesized image with better visibility than other existing learning-based image synthesis methods. Compared with the rule-based image synthesis method used as the target image, the proposed method has an advantage in processing speed by reducing the processing time to three times or more.

Mandibular fracture is one of the most frequent injuries in oral and maxillo-facial surgery. Radiologists diagnose mandibular fractures using panoramic radiography and cone-beam computed tomography (CBCT). Panoramic radiography is a conventional imaging modality, which is less complicated than CBCT. This paper proposes the diagnosis method of mandibular fractures in a panoramic radiograph based on a deep learning system without the intervention of radiologists. The deep learning system used has a one-stage detection called you only look once (YOLO). To improve detection accuracy, panoramic radiographs as input images are augmented using gamma modulation, multi-bounding boxes, single-scale luminance adaptation transform, and multi-scale luminance adaptation transform methods. Our results showed better detection performance than the conventional method using YOLO-based deep learning. Hence, it will be helpful for radiologists to double-check the diagnosis of mandibular fractures.

Crizotinib is used in the clinic for treating patients with ALK- or ROS1-positive non-small-cell lung carcinoma. The objective of the present study was to determine if crizotinib enantiomers could induce changes to the properties of cancer and cancer stem cell (CSC)-like cells at a high concentration (∼ 3 μM). While (R)-crizotinib induced changes in morphologies or sizes of cells, (S)-crizotinib did not. Pretreatment with (R)-crizotinib suppressed the proliferation of cancer or CSC-like cells in vitro and tumor growth in vivo. In vivo administration of (R)-crizotinib inhibited the growth of tumors formed from CSC-like cells by 72%. %. Along with the morphological changes induced by (R)-crizotinib, the expression levels of CD44 (NCI-H23 and HCT-15), ALDH1 (NCI-H460), nanog (PC-3), and Oct-4A (CSC-like cells), which appear to be specific marker proteins, were greatly changed, suggesting that changes in cellular properties accompanied the morphological changes in the cells. The expression levels of Snail, Slug, and E-cadherin were also greatly altered by (R)-crizotinib. Among several signal transduction molecules examined, AMPK phosphorylation appeared to be selectively inhibited by (R)-crizotinib. BML-275 (an AMPK inhibitor) and AMPKα2 siRNA efficiently induced morphological changes to all types of cells examined, suggesting that (R)-crizotinib might cause losses of characteristics of cancer or CSCs via inhibition of AMPK. These results indicate that (R)-crizotinib might be an effective anticancer agent that can cause alteration in cancer cell properties.

This study aims to develop a spatial dual-sensor module for acquiring visible and near-infrared images in the same space without time shifting and to synthesize the captured images. The proposed method synthesizes visible and near-infrared images using contourlet transform, principal component analysis, and iCAM06, while the blending method uses color information in a visible image and detailed information in an infrared image. The contourlet transform obtains detailed information and can decompose an image into directional images, making it better in obtaining detailed information than decomposition algorithms. The global tone information is enhanced by iCAM06, which is used for high-dynamic range imaging. The result of the blended images shows a clear appearance through both the compressed tone information of the visible image and the details of the infrared image.

For the image conversion from low dynamic range images to high dynamic range images, we considered the possibility of using the Generative Adversarial Network (GAN) as one of the deep neural network methods. Deep learning requires a lot of data before building a module, but once creation is done, it is convenient to use it. In this paper, we proposed a weighting map for a local luminance based learning to reconstruct locally tone-mapped images.

Purpose The purpose of this study is to investigate the effect of the cross-link position on the rod fracture phenomenon during pedicle subtraction osteotomy (PSO) surgery using finite element model (FEM). Methods A three-dimensional finite element model of a lumbar spine with sagittal imbalance was constructed using computed tomography data of a 65-year-old female patient. After simulating the standard PSO at the L4 level, we constructed four models, specifically a model without a cross-link and three models with a cross-link at three different sites. The peak von Mises stress (PVMS) of the rod around the PSO site was measured after applying physiological loads (flexion, extension, axial rotation, and lateral bending) in each model. Results The measured PVMS outcomes at the PSO site were 135.8, 135.9, 208.9, and 384.7 MPa for model 1, 2, 3, and 4 during flexion, and 180.0, 180.1, 210.1, and 445.7 MPa during extension. These results show that when the cross-link is located at the PSO site, the rod stress at the PSO site increases significantly during flexion and extension. As the cross-link moved away from the PSO site, the effect on the rod stress decreased. When the cross-link was placed two levels away from the PSO site, the rod stress was scarcely affected. Conclusion When the cross-link during PSO surgery was positioned two levels away from the PSO site, the risk of rod fracture did not increase.

Purpose This study examined whether the individual and organizational factors of ecological systems theory are associated with job satisfaction among nurses in South Korea. Background Nursing shortages and high turnover rates are a global issue in healthcare settings, and job satisfaction is significantly associated with the turnover intention of nurses. Therefore, efforts to promote job satisfaction are needed to decrease the high turnover rates among nurses as well as promote care quality and patient safety. Design A cross-sectional study was performed. This paper adhered to the STROBE guidelines. Methods A sample of 438 nurses working in five secondary or tertiary hospitals were surveyed. The study instruments included work-life balance, resilience, insomnia, and job satisfaction. Results Using multilevel analysis, both individual and organizational factors were associated significantly with job satisfaction, and variance at the group level accounted for 19.98% of the total variance of job satisfaction. Among the individual factors, marital status, and work-life balance were significantly associated with job satisfaction. At the organizational level, the group mean resilience score was significantly associated with job satisfaction (p Conclusion The psychosocial characteristics of individual nurses and their affiliated groups (nursing units) were significant in explaining the job satisfaction of nurses. Relevance to clinical practice Both individual-focused and group-focused interventions are needed to improve job satisfaction and decrease the turnover intention.

This study proposes a method of blending visible and near-infrared (NIR) images to enhance their edge details and local contrast based on the Laplacian pyramid and principal component analysis (PCA). In the proposed method, both the Laplacian pyramid and PCA are implemented to generate a radiance map. Using the PCA algorithm, the soft-mixing method and the mask-skipping filter were applied when the images were fused. The color compensation method uses the ratio between the radiance map fused by the Laplacian pyramid and the PCA algorithm and the luminance channel of the visible image to preserve the chrominance of the visible image. The results show that the proposed method improves edge details and local contrast effectively.

This research is focused on coagulation and sand filtration process as a pretreatment of RO seawater desalination. RO systems require sufficient and reliable pretreatment process to produce superior quality of RO feedwater that can mitigate RO membrane fouling. This experiment was conducted to investigate the effectiveness of coagulation and filtration process under various experimental conditions including different coagulant dose, flocculation mixing intensity and time, turbidity, and filtration rate. The experimental results showed that the optimum pretreatment conditions resulting in lower SDI value suitable for RO feedwater were coagulation pH 6.5, raw water turbidity greater than 4 NTU, and media bed depth greater than 550 mm. However, flocculation mixing intensity, coagulant dose, and filtration rate relatively affected little on the filtration efficiency.

This work was performed to investigate proper condition of coagulation treatment as UF process pretreatment that consider UF permeate flux and residual Al concentration. The coagulant used an alum as and PACl (r

Pretreatment process is the critical step of RO (Reverse Osmosis) membrane desalination plant in order to prevent RO membrane fouling. The pretreatment as a key component of RO process must be designed to produce a constant and high quality RO feedwater which has low silt density index (SDI). This experiment was conducted to assess parameters affecting SDI value, such as pH, seawater turbidity, temperature, and coagulant dose. The experimental results indicated that the source seawater turbidity did cause little effects on SDI values of filtered water. The 0.45 um hydrophilic membrane was more appropriate than the hydrophobic membrane for measuring SDI. The SDI value was increased with decreasing pH under the condition of below pH 7.0. In addition, the water temperature significantly affected the SDI values, showing higher SDI value with lower water temperature.

Silver nanoparticles coated with silica can be obtained by the reduction of with hydrazine in the presence of NaOH-stabilized, active silicic acid (polysilicic acid). The size of the silver nanoparticles and the silica shell thicknesses were affected by varying the hydrazine content, the active silicic acid content and the experimental method (e.g. hydrothermal method). Typically, silver nanoparticles sized around 40 nm were aggregated, connected by silica. The presence of peaks centered around 400 nm in UV-vis spectra corresponds to the surface plasmon resonance of silver nanoparticles. The size of the aggregated silver nanoparticles increased with increasing hydrazine concentration. Under hydrothermal conditions at the formation of individual silica particles was observed and the sizes of the silver nanoparticles were reduced. The hydrothermal treatment of silver nanoparticles at gives a well-defined Ag@ core-shell in aggregated silica sol particles. The absorption band observed at around 412 nm were red-shifted with respect to the uncoated silver nanoparticles ( = 399 nm) due to the larger refractive index of silica compared to that of water. The formation of silver nanoparticles coated with silica is confirmed by UV-visible absorption spectra, transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) data.

In borohydride-protected nanosilvers in laponite sol, the silver particles aggregate to form short chains and a dumbbell shape. The H NMR measurements in this study represent, to our knowledge, the first observation of proton resonances of borohydride-protected nanosilvers in aqueous solution. Borohydride on nanosilver can be exchanged with 11-mercaptoundecanoic acid (MUA) or trioctylphosphine (TOP). Transmission electron microscopy and UV-Vis spectroscopy data show that the number of aggregated silver nanoparticles decreases upon addition of aforementioned ligands due to the formation of silver MPCs (monolayer-protected clusters). Adsorption of MUA or TOP on nanosilver is confirmed through the observation of broad proton resonances of MPCs in 1 H NMR spectra.

Purpose: Purpose was to explore associations between sleep duration and metabolic syndrome (MS) risks, and to determine factors associated with self-rated health (SRH) of adults with MS compared to other adults. Methods: This is a secondary data analysis based on the Fifth Korea National Health and Nutrition Examination Survey KNHANES V (N=12662). Study instruments included sleep duration, MS risk factors, SRH and health-related quality of life (HRQoL). Results: Mean age of participants was 43.68±12.26 years. Fifty-eight percent were women, and 18.3% were identified as having MS. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and SRH were significantly different according to sleep duration (p

This paper proposes a system model to improve the utilization of smart appliances for smart grid demand response by expanding smart energy profile (SEP) 2.0. The original smart appliance system model was designed assuming that there exists a device with an energy service interface model in the home environment, but this is not common in the real world. Our proposed expansion of SEP 2.0 allows the use of smart appliances even without an energy service interface; thus, it can lead to an increase in the demand response participation of appliances. The effectiveness of the proposed model is verified through a field test conducted with appliance manufacturers and a utility company.

Power line communication (PLC) technology can be a viable solution for the future ubiquitous networks because it provides a cheaper alternative to other wired technology currently being used for communication. However, for the better performance of PLC-based networks, their physical layer and medium access control (MAC) protocols need to be a lot more enhanced. Recently, many physical frame encoding technologies have been developed, but the MAC protocols still need more consideration because of the unique characteristics of power line channels. In this paper, we describe an overview of the Korea Standard power line MAC protocol (called "KS-MAC"). We also report the simulation results performed with the well-known simulation tool of network simulator-2 (i.e., NS-2) and compared with the actual field test data.

For most applications in wireless sensor networks (WSNs), it is often assumed that the deployment of sensor nodes is unmanaged and random, so the density of local node may vary throughout the network. In high density areas, nodes consume more energy due to frequent packet collisions and retransmissions. One of the ways to alleviate this problem is to adjust the transmission power of each sensor node by means of efficient topology control mechanisms. In this paper, we propose an efficient topology control for energy conservation, named "k+ Neigh." In our scheme, each sensor node reduces its transmission power so that it has minimum number of k neighbor nodes. Later, we will show that the preferred value of the k is 2 by simulation. In the performance evaluation, the proposed scheme can make significant energy saving with such a topology structure, while the network connectivity is guaranteed.

In the area of wireless sensor networks, achieving minimum energy consumption is a very important research issue. A number of energy efficient protocols have been proposed, mostly based on a layered design approach, which means that they are focused on designing optimal strategies for “single” layer only. In this paper, we take an alternative approach i.e., a cross-layer design, and present a new MAC protocol named MAC-CROSS. In this new approach, the interactions between MAC and Routing layers are fully exploited to achieve energy efficiency for wireless sensor networks. More precisely, in the proposed MAC-CROSS algorithm, routing information at the network layer is utilized for the MAC layer such that it can maximize a sleep duration of each node. Through implementation on a Mica Mote platform and simulation study using the NS-2, we evaluate a performance of the presented MAC-CROSS and prove its substantial performance gains.