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Abstract Background Risk factors for local recurrence in patients with metastatic spinal cord compression (MSCC) has not been clearly investigated. So, the purpose of this study was to identify risk factors causing local recurrence following surgeries in patients with MSCC. Methods We conducted a retrospective comparative study on 304 patients who underwent surgery for MSCC between March 2014 and February 2020. Local recurrence rate (LRR) was analyzed according to demographic variables, radiological variables such as level of spinal metastasis, number of non-spinal bone metastases, degree of spinal cord compression, spinal instability, and pathological fracture, and treatment-related variables such as origin of tumor, surgical treatment methods, and pre- and post- operative radiation therapy. Univariate and multivariate logistic regression analyses were performed to reveal the risk factors for local recurrence. Results Among 304 patients with MSCC, 50 patients (16.4%) experienced local recurrence after surgery. Of the surgical methods, decompression alone (26/50, 52.0%) showed higher LRR compared to decompression with fixation (9/177, 5.1%) or corpectomy (11/89, 12.4%), (P = 0.002 and P = 0.018, respectively). Patients with renal cell carcinoma revealed higher LRR compared to other types (P = 0.014). It was found that the 3 or more level of spinal metastasis (P = 0.001), the 3 or more of extraspinal bone metastases (P = 0.028), and pathologic fracture (P = 0.003) were related with higher LRR. Smoking is also an independent risk factor for local recurrence in patients who underwent fixation (P = 0.026). Conclusions Symptomatic local recurrence may be influenced by several factors, including the extent of spinal and extraspinal bone metastasis, pathologic fractures, surgical approach, and tumor origin (RCC). These factors should be carefully considered by surgeons when evaluating the risk of symptomatic local recurrence after surgery.

The current study aims to investigate a prediction model from reflection values and the spectral angle mapper (SAM) obtained from hyperspectral imaging (HSI) technology for the detection of three types of foreign materials – a branch, a knife, and rubber – that are associated with the various fruit-processed products. The study found that the maximum and minimum reflection values in the 900 to 1700 nm range for juices (apple, grape, tomato) and jams (strawberry, peach, tomato) differed depending on the presence or absence of physical hazards. The presence of physical hazards was also confirmed by the color difference in the SAM image. The partial least squares discriminant analysis model (PLS-DA) and logistic regression implemented on the Jupyter Notebook platform through the Anaconda prompt provided accuracy, F1 score, specificity, and sensitivity based on the confusion matrix. The maximum value was 100.0 %, while the minimum value was 97.6 % of the result of the PLS-DA modeling in the testing set. Logistic regression modeling also had a similar result: the maximum value was 100.0 %, while the minimum value was 97.8 % in the testing set. The sensitivity value in the testing set, which is a meaningful result for detecting physical hazards, was a maximum of 100.0 % for both PLS-DA and logistic regression. Results from the current study suggest that the reflection value and SAM data obtained through hyperspectral imaging could build a big data platform for early determination of physical hazards during agricultural product processing.

Abstract Endoscopic submucosal dissection (ESD) is technically challenging and requires a high level of skill. However, there is no effective method of exposing the submucosal plane during dissection. In this study, the efficacy of robot arm-assisted tissue traction for gastric ESD was evaluated using an in vivo porcine model. The stomach of each pig was divided into eight locations. In the conventional ESD (C-ESD) group, one ESD was performed at each location (N = 8). In the robot arm-assisted ESD (R-ESD) group, two ESDs were performed at each location (N = 16). The primary endpoint was the submucosal dissection speed (mm2/s). The robot arm could apply tissue traction in the desired direction and successfully expose the submucosal plane during submucosal dissection in all lesion locations. The submucosal dissection speed was significantly faster in the R-ESD group than in the C-ESD group (p = 0.005). The blind dissection rate was significantly lower in the R-ESD group (P = 0.000). The robotic arm-assisted traction in ESD enabled a significant improvement in submucosal dissection speed, blind dissection rate which suggests the potential for making ESD easier and enhancing procedural efficiency and safety.

IntroductionAssisted reproductive technologies (ARTs), such as intracytoplasmic sperm injection and embryo transfer, are essential for generating genetically edited monkeys. Despite their importance, ARTs face challenges in recipient selection in terms of time and the number of animals required. The potential of superovulated monkeys, commonly used as oocyte donors, to serve as surrogate mothers, remains underexplored. The study aimed to compare the efficacy of superovulated and uterine-embryo synchronized recipients of embryo transfer in cynomolgus monkeys (Macaca fascicularis).MethodsThis study involved 23 cynomolgus monkeys divided into two groups–12 superovulated recipients and 11 synchronized recipients. The evaluation criteria included measuring endometrial thickness on the day of embryo transfer and calculating pregnancy and implantation rates to compare outcomes between groups.ResultsThe study found no statistically significant differences in endometrial thickness (superovulated: 4.48 ± 1.36 mm, synchronized: 5.15 ± 1.58 mm), pregnancy rates (superovulated: 30.8%, synchronized: 41.7%), and implantation rates (superovulated: 14.3%, synchronized: 21.9%) between the groups (p > 0.05).ConclusionThe observations indicate that superovulated recipients are as effective as synchronized recipients for embryo transfer in cynomolgus monkeys. This suggests that superovulated recipients can serve as viable options, offering an efficient and practical approach to facilitate the generation of gene-edited models in this species.

Degenerative cervical myelopathy (DCM) is a leading cause of disability, and its surgical management is crucial for improving patient neurological outcomes. Given the varied presentations and severities of DCM, treatment options are diverse. Surgeons often face challenges in selecting the most appropriate surgical approach because there is no universally correct answer. This narrative review aimed to aid the decision-making process in treating DCM by presenting a structured treatment algorithm. The authors categorized surgical scenarios based on an algorithm, outlining suitable treatment methods for each case. Four primary scenarios were identified based on the number of levels requiring surgery and K-line status: (1) K-line (+) and ≤3 levels, (2) K-line (+) and ≥3 levels, (3) K-line (−) and ≤3 levels, and (4) K-line (−) and ≥3 levels. This categorization aids in determining the appropriateness of anterior or posterior approaches and the necessity for fusion, considering the surgical level and K-line status. The complexity of surgical situations and diversity of treatment methods for DCM can be effectively managed using an algorithmic approach. Furthermore, surgical techniques that minimize the stages and address challenging conditions could enhance treatment outcomes in DCM.

Study Design Retrospective study. Purpose This study aimed to evaluate how osteoporosis affected the clinical and radiological outcomes of patients who underwent anterior cervical discectomy and fusion (ACDF) with plating. Overview of Literature The incidence of complications associated with implants is high when ACDF is performed in patients with poor bone quality. Methods In total, 101 patients without (T-score ≥1.0, group A) and 25 with (T-score ≤−2.5, group B) osteoporosis who underwent single-level ACDF with plating were followed up for >2 years. The clinical and radiological outcomes were compared between the two groups. The fusion rate and implant-related complications were evaluated. Results Although clinical outcomes such as visual analog scale scores for the arm (2.0±2.3 vs. 2.4±2.9, p=0.490) and neck pain (1.4±1.9 vs. 1.8±2.2, p=0.343) and neck disability index (7.7±7.1 vs. 9.9±7.5, p=0.225) were slightly higher in group B, no statistically significant difference was noted. Cage subsidence (13.9% vs. 16.0%, p=0.755) and plate migration (7.9% vs. 8.0%, p=1.000) rates did not differ between the two groups. The fusion rate at 1 year postoperatively was higher in group A than in group B (80.3% vs. 68.2%, p=0.139) and slightly increased in both groups (94.6% vs. 86.4%, p=0.178) at the final follow-up. Conclusions Osteoporosis did not significantly affect the rate of cage subsidence or plate migration after cervical fusion. After ACDF, increased cage subsidence and implant migration rates had no significant effect on clinical outcomes.

Objective Even minor sacral slanting can influence T1 tilt and shoulder balance. Yet, the relationship between sacral slanting and postoperative shoulder imbalance (PSI) has not been previously explored. To determine risk factors for PSI in Lenke 2A adolescent idiopathic scoliosis (AIS) patients, with an emphasis on sacral slanting. Methods The study encompassed 96 consecutive patients who had undergone posterior correction and fusion surgery for Lenke type 2A AIS. Patients were grouped into PSI(+) and PSI(-) based on postoperative outcomes. Additionally, they were classified into left-sided slanting, no slanting, and right-sided slanting groups according to the degree of sacral slanting. Various radiological measures were compared. Results Patients in the PSI(+) group exhibited a smaller preoperative proximal thoracic curve and a higher main thoracic curve correction rate than those in the PSI(-) group. The presence or absence of sacral slanting did not exhibit a significant variation in PSI occurrence. However, the right-sided sacral slanting group showed a larger delta radiologic shoulder height compared to the other 2 groups (7.1 mm vs. 1.5 & 3.3 mm). Conclusion Sacral slanting was not directly linked to the development of PSI. Despite the common postoperative elevation of the left shoulder, the shoulder height differences decreased over the follow-up period. Especially in cases with a right-sided tilted sacrum, the PSI demonstrated progressive improvement, with an associated increase in the rightward distal wedging angle, leading to distal adding-on.

Background and Objective: The modified prone position, which is an alteration of the standard prone position, reduces cardiac preload. Dynamic variables including stroke volume variation (SVV), pulse pressure variation (PPV), and pleth variability index (PVI) are reliable predictors for fluid responsiveness during surgery. To the best of our knowledge, no studies assessing dynamic variables for fluid responsiveness have been conducted in the modified prone position. This study aimed to evaluate the ability of PVI to predict fluid responsiveness in the modified prone position during cervical spine surgery. Materials and Methods: PVI, SVV, and PPV were recorded at the following times: before and after a 4 mL/kg crystalloid load in the supine position (T1, T2); after placement in the modified prone position (T3); and before and after a 4 mL/kg crystalloid administration in the modified prone position (T4, T5). Fluid responsiveness was defined as stroke volume (SV) ≥ 15%, assessed by the FloTrac/Vigileo™ (Edwards Lifesciences Corp, Irvine, CA, USA). Receiver operating characteristic (ROC) curves were analyzed to identify changes in each dynamic variable that could predict fluid responsiveness in the modified prone position. Results: Data from a total of 43 subjects were analyzed. In the supine position, 21 subjects were responders. After subjects were placed in the modified prone position, SV significantly decreased, while PVI, SVV, and PPV significantly increased (p < 0.001 for all). In the modified prone position, 13 subjects were responders, and the areas under the ROC curves for ΔPVI, ΔSVV, and ΔPPV after fluid loading were 0.524 (95% confidence interval [CI] 0.329–0.730, p = 0.476), 0.749 (95% CI 0.566–0.931, p = 0.004), and 0.790 (95% CI 0.641–0.938, p < 0.001), respectively. Conclusions: Crystalloid pre-loading could not mitigate the decrease in SV caused by the modified prone position. Changes in PVI were less reliable in predicting fluid responsiveness in the modified prone position.

Abstract Background Cynomolgus monkeys (Macaca fascicularis) are essential in biomedical research, including reproductive studies. However, the application of human estimated foetal weight (EFW) formulas using ultrasonography (USG) in these non‐human primates is not well established. Objectives This study aims to evaluate the applicability of human EFW formulas for estimating foetal weight in cynomolgus monkeys at approximately 130 days of gestation. Methods Our study involved nine pregnant cynomolgus monkeys. We measured foetal parameters, including biparietal diameter, head circumference, abdominal circumference and femur length using USG. The EFW was calculated using 11 human EFW formulas. The actual birthweight (ABW) was recorded following Cesarean section, the day after the EFW calculation. For comparing EFW and ABW, we employed statistical methods such as mean absolute percentage error (APE) and Bland–Altman analysis. Results The ABW ranged between 200.36 and 291.33 g. Among the 11 formulas, the Combs formula showed the lowest APE (4.3%) and highest correlation with ABW (p

We demonstrate that the shorter channel self-aligned top-gate (SA TG) coplanar indiumgallium- zinc oxide (IGZO) thin-film transistors (TFTs), with negative voltage applied to the back-gate, exhibit superior characteristics as driving transistors in organic light-emitting diode (OLED) pixels compared to their longer channel counterparts. The shorter channel IGZO TFTs (with a channel length (L) of 3 μm) biased with a back gate voltage of −3.5 V showed a larger subthreshold swing (SS = 0.21 V/dec) than the longer channel ones (with L = 5 μm, SS = 0.16 V/dec) with a similar threshold value (VTH = 0.7–0.8 V). A large SS is beneficial for controlling grayscale levels, especially at low gray levels, when IGZO TFTs are used as driving transistors in OLED pixels. Furthermore, the negatively back-gate-biased shorter channel SA TG coplanar IGZO TFTs exhibited significantly enhanced electrical stability compared to the longer channel ones under both positive gate bias and hot carrier stresses. The findings of this study are expected to be useful in expanding the utility of IGZO TFTs in OLED displays.

Background and Objectives: Posterior cervical foraminotomy (PCF) aims to resolve cervical radiculopathy while preserving range of motion (ROM). However, its effectiveness in maintaining ROM is uncertain. This study investigates the changes in ROM after PCF and identifies preoperative factors that influence ROM reduction post surgery. Materials and Methods: This retrospective cohort study included patients treated at our hospital from August 2016 to September 2021. Clinical outcomes were assessed using the visual analog scale (VAS) for neck and arm pain and the neck disability index (NDI). Radiological outcomes included the segmental angle (SA), cervical angle (CA), C2–C7 SVA, Pfirrmann grade, extent of facetectomy, foraminal stenosis, and ROM. Patients were categorized into two groups based on segmental ROM changes: decreased (Group D) and maintained (Group M). Radiological and clinical outcomes were compared between the groups. Univariate and multivariate regression analyses were performed to identify risk factors for ROM loss after PCF. Results: 76 patients were included: 34 in Group D and 42 in Group M, with no demographic differences. Preoperatively, Group D had significantly larger flexion segmental and cervical angles than Group M (segmental, p < 0.001; cervical, p = 0.001). Group D also had a higher Pfirrmann grade (p = 0.014) and more bony bridge formations (p = 0.004). While no significant differences were observed in arm pain VAS and NDI scores, Group D exhibited worse neck pain VAS at the last follow-up (p = 0.03). Univariate linear regression indicated that preoperative segmental ROM (p < 0.001, B = 0.82) and bony bridge formation (p = 0.046, B = 5.33) were significant predictors of ROM loss post PCF. Conclusions: Patients with higher preoperative flexion angles and Pfirrmann grades at the operative level are at an increased risk for ROM loss and neck pain and often exhibit bony bridge formation. Accounting for these factors can improve surgical planning and patient outcomes.

The accurate and timely prediction of Napa cabbage fresh weight is essential for optimizing harvest timing, crop management, and supply chain logistics, which ultimately contributes to food security and price stabilization. Traditional manual sampling methods are labor-intensive and lack precision. This study introduces an artificial intelligence (AI)-powered model that utilizes unmanned aerial systems (UAS)-based multi-sensor data to predict Napa cabbage fresh weight. The model was developed using high-resolution RGB, multispectral (MSP), and thermal infrared (TIR) imagery collected throughout the 2020 growing season. The imagery was used to extract various vegetation indices, crop features (vegetation fraction, crop height model), and a water stress indicator (CWSI). The deep neural network (DNN) model consistently outperformed support vector machine (SVM) and random forest (RF) models, achieving the highest accuracy (R2 = 0.82, RMSE = 0.47 kg) during the mid-to-late rosette growth stage (35–42 days after planting, DAP). The model’s accuracy improved with cabbage maturity, emphasizing the importance of the heading stage for fresh weight estimation. The model slightly underestimated the weight of Napa cabbages exceeding 5 kg, potentially due to limited samples and saturation effects of vegetation indices. The overall error rate was less than 5%, demonstrating the feasibility of this approach. Spatial analysis further revealed that the model accurately captured variability in Napa cabbage growth across different soil types and irrigation conditions, particularly reflecting the positive impact of drip irrigation. This study highlights the potential of UAS-based multi-sensor data and AI for accurate and non-invasive prediction of Napa cabbage fresh weight, providing a valuable tool for optimizing harvest timing and crop management. Future research should focus on refining the model for specific weight ranges and diverse environmental conditions, and extending its application to other crops.

Study Design Retrospective comparative study. Purpose This study aimed to investigate the effects of the lordotic angle of cages on sagittal alignment in patients who underwent 1- or 2-level posterior lumbar interbody fusion (PLIF), including the L5–S1 level. Overview of Literature Few studies have addressed the effects of the lordotic angle of cages on regional and global sagittal balance in patients undergoing PLIF at the L5–S1 level. Methods Sixty-one patients who underwent 1- or 2-level PLIF, including the L5–S1 level, were divided into two groups based on the lordotic angle of cages (4° and 8° in 41 and 20 patients, respectively). Clinical and radiological parameters were compared. Correlation analyzes were performed to reveal the effect of flexibility and position of cages on the regional sagittal parameters. Results Pre- and postoperative clinical and radiological parameters were not different between the two groups. Although clinical outcomes improved postoperatively, sagittal parameters did not improve postoperatively in both groups. Patients who underwent 1-level PLIF at the L5–S1 level with the use of 8° cages showed no postoperative improvement (segmental angle: 16.1°–15.9°, p=0.140; lumbar lordosis: 44.8°–47.8°, p=0.740) of regional sagittal parameters. The degree of anterior location of cages showed a positive correlation with the postoperative restoration of the segmental angle (p=0.012 and p=0.050 at 1 and 2 years postoperatively, respectively). Conclusions Clinical and radiological outcomes based on the lordotic angle of cages were not different. Even with the use of 8° cages and regardless of the more anterior position of cages, sagittal alignment did not improve in cases involving the L5–S1 level. PLIF at the L5–S1 level should be used with caution because improvement in sagittal alignment did not occur.

Occasionally, ossification of the posterior longitudinal ligament (OPLL) causes cord compression, resulting in cervical myelopathy. OPLL differs from other causes of cervical spondylotic myelopathy in several ways, and the surgical strategy should be chosen with OPLL’s characteristics in mind. Although both the anterior and posterior approaches are effective surgical methods for the treatment of OPLL cervical myelopathy, they each have their own set of benefits and drawbacks. Anterior decompression and fusion (ADF) may improve neurological recovery, restore lordosis, and prevent OPLL mass progression. The benefits can be seen in patients with a high canal occupying ratio or kyphotic alignment. We discussed the benefits, limitations, indications, and surgical techniques of ADF for the treatment of OPLL-induced cervical myelopathy in this narrative.

Objective This retrospective cohort study has been aimed at evaluating the incidence of complications after vertebral body sliding osteotomy (VBSO) and analyzing some cases. Furthermore, the complications of VBSO were compared with those of anterior cervical corpectomy and fusion (ACCF). Methods This study included 154 patients who underwent VBSO (n = 109) or ACCF (n = 45) for cervical myelopathy and were followed up for > 2 years. Surgical complications, clinical and radiological outcomes were analyzed. Results The most common surgical complications after VBSO were dysphagia (n = 8, 7.3%) and significant subsidence (n = 6, 5.5%). There were 5 cases of C5 palsy (4.6%), followed by dysphonia (n = 4, 3.7%), implant failure (n = 3, 2.8%), pseudoarthrosis (n = 3, 2.8%), dural tears (n = 2, 1.8%), and reoperation (n = 2, 1.8%). C5 palsy and dysphagia did not require additional treatment and spontaneously resolved. The rates of reoperation (VBSO, 1.8%; ACCF, 11.1%; p = 0.02) and subsidence (VBSO, 5.5%; ACCF, 40%; p < 0.01) were significantly lower in VBSO than in ACCF. VBSO restored more C2–7 lordosis (VBSO, 13.9°±7.5°; ACCF, 10.1°±8.0°; p = 0.02) and segmental lordosis (VBSO, 15.7°±7.1°; ACCF, 6.6°±10.2°; p < 0.01) than ACCF. The clinical outcomes did not significantly differ between both groups. Conclusion VBSO has advantages over ACCF in terms of low rate of surgical complications related to reoperation and significant subsidence. However, dural tears may still occur despite the lessened need for ossified posterior longitudinal ligament lesion manipulation in VBSO; hence, caution is warranted.

Abstract Leiomyosarcoma, a malignant tumour originating from smooth muscle cells, has rarely been documented in non‐human primates. In this case study, a 7‐year‐old female cynomolgus macaque (Macaca fascicularis) presented with a rapidly growing mass overlying the left elbow joint. Radiographs indicated the presence of a soft tissue neoplasm without any associated bone involvement. The mass was surgically resected. Histological and immunohistochemical analyses revealed spindle‐shaped cells with eosinophilic cytoplasm that resembled smooth muscle cells, exhibiting positive immunoreactions for vimentin, desmin and smooth muscle actin and a negative reaction for pan‐cytokeratin. This is the first reported case of subcutaneous leiomyosarcoma in a cynomolgus macaque and provides important insights into the incidence and characteristics of this condition in this species.

Objectives To confirm both efficiency and sustainability of algal growth inhibition, various laboratory-scale experiments were conducted and the growth inhibitory effect of Microcystis aeruginosa (M. aeruginosa) was investigated through ultrasonic re-irradiation during the regrowth period after the first ultrasound irradiation. Methods Experiments with different times of irradiation [i.e., control group A (0 hr), experimental group B (2 hr) applied with only the first ultrasound irradiation, and experimental group C (0.5 hr), D (1 hr), and E (1.5 hr) applied with both first and second irradiations] were performed. Results and Discussion As a result of both Chlorophyll-a (Chl-a) concentration and cell number of M. aeruginosa, the experimental group (B) with only first ultrasound irradiation (2 hr) displayed rapid regrowth of algae after initial decrease whereas the experimental group (C, D, and E) with both first ultrasound irradiation (2 hr) and second ultrasound irradiation (0.5 hr, 1 hr, and 1.5 hr) confirmed the delay of algae regrowth. Based on the specific growth rate constant (µ) and first order decay rate constant (k), algal growth from the experimental groups (C, D, E) with the secondary ultrasound irradiation was more significantly inhibited due to repetitive inactivation of algae growth. According to the SEM and TEM results, damages to algae cells were clearly observed under the influence of ultrasound, and both decrease in gas vesicles and rupture of cell membrane in M. aeruginosa were also monitored. Conclusion Through this study, the algae growth inhibitory effect by ultrasonic irradiations was confirmed, and the re-irradiation of ultrasound contributed to the repetitive inactivation of algae growth, indicating that the second ultrasonic irradiation time required to inhibit algal regrowth can be reduced compared to the first irradiation. Therefore, periodic ultrasonic irradiation is required for long-term inhibition of algae growth in stagnant waters, but the appropriate frequency of ultrasonic irradiation may vary depending on the influence of various complex factors such as the size of the stagnant waters, the frequency of algal blooms, water temperature, light irradiation, nutrients, flow rate, etc. Finally, many field studies under various conditions are warranted to establish an optimized ultrasound irradiation protocol.

Grade schoolers and teenagers wonder how tall they will be, as there is a tendency to prefer taller stature for many years. Child’s height growth is one of the continuous interests of the parents from the past to the present for many reasons, not only their children’s outer beauty but also health status of children. Pediatricians also want to make sure a child is growing as expected because the height growth of children is an important indicator for monitoring a child’s nutrition and diseases. In many previous studies, adult height prediction method using growth curves is used widely. Unfortunately, growth curves are based on longitudinal cohort studies which are very challenging to conduct. That’s why it is hard to find the related studies for certain ethnic group. In this study, we collected 2,687 Korean height data including parental heights and children’s heights by ourselves in the same format as Galton’s Height data at 1880s in the United Kingdom. Then, we focus on the influence of parental height on child’s height conducting various analysis comparing Galton’s and Korean height data. Especially, we find out the linearity of child’s height varies depending on the combination of each parental height through visualization analysis. Finally, we propose our method of deploying the best among various machine learning techniques according to the combination of parental height. The combination is based on distribution of each parental height. And it outperforms achieving RMSE under 3.5 compared to single machine learning models which cannot achieve RMSE even under 4.0. It will be a simple and good application for many of pediatricians and parents who care a lot about their children’s height growth.

Abstract The characteristics of animal distribution are determined by interactions between the resource requirements of animals and ecological factors. This study sought to evaluate the effects of diverse ecological factors on the home range and core area of red-backed voles (Myodes regulus) in a natural deciduous forest located on Mt. Gariwang, Pyeongchang and Jeongseon, South Korea. Our study focused on four types of ecological factors: topography, climate, cover, and demography. A total of 29 voles were radio-tracked from August to September 2021. Home range (95% utilization distribution; UD) and core area (50% UD) were calculated using the kernel density estimator (KDE). The home range (1659.49 m2) and core area (317.08 m2) were negatively affected by altitude. The lunar phase and temperature negatively and positively influenced the home range and core area, respectively. The home range was positively affected by understory vegetation, whereas the core area was not. The core area increased within microhabitats with a high density of conspecific individuals, with males having a larger home range (2006.19 m2) and core area (375.40 m2) than females (1043.13 m2 and 213.39 m2, respectively). These findings provide a deeper understanding of the diverse ecological factors affecting the distributions of animals, especially small rodents.

During outbreaks of infectious diseases, such as COVID-19, it is critical to rapidly determine treatment priorities and identify patients requiring hospitalization based on clinical severity. Although various machine learning models have been developed to predict COVID-19 severity, most have limitations, such as small dataset sizes, the limited availability of clinical variables, or a constrained classification of severity levels by a single classifier. In this paper, we propose an adaptive stacking ensemble technique that identifies various COVID-19 patient severity levels and separates them into three formats: Type 1 (low or high severity), Type 2 (mild, severe, critical), and Type 3 (asymptomatic, mild, moderate, severe, fatal). To enhance the model’s generalizability, we utilized a nationwide dataset from the South Korean government, comprising data from 5644 patients across over 100 hospitals. To address the limited availability of clinical variables, our technique employs data-driven strategies and a proposed feature selection method. This ensures the availability of clinical variables across diverse hospital environments. To construct optimal stacking ensemble models, our technique adaptively selects candidate base classifiers by analyzing the correlation between their predicted outcomes and performance. It then automatically determines the optimal multi-layer combination of base and meta-classifiers using a greedy search algorithm. To further improve the performance, we applied various techniques, including imputation of missing values and oversampling. The experimental results demonstrate that our stacking ensemble models significantly outperform existing single classifiers and AutoML approaches, with improvements of 6.42% and 8.86% in F1 and AUC scores for Type 1, 9.59% and 6.68% for Type 2, and 11.94% and 9.24% for Type 3, respectively. Consequently, our approach improves the prediction of COVID-19 severity levels and potentially assists frontline healthcare providers in making informed decisions.

Abstract Background Although several studies on the Mg-Zn-Ca system have focused on alloy compositions that are restricted to solid solutions, the influence of the solid solution component of Ca on Mg-Zn alloys is unknown. Therefore, to broaden its utility in orthopedic applications, studies on the influence of the addition of Ca on the microstructural, mechanical, and corrosion properties of Mg-Zn alloys should be conducted. In this study, an in-depth investigation of the effect of Ca on the mechanical and bio-corrosion characteristics of the Mg-Zn alloy was performed for the optimization of a clinically approved Mg alloy system comprising Ca and Zn. Methods The Mg alloy was fabricated by gravitational melting of high purity Mg, Ca, and Zn metal grains under an Ar gas environment. The surface and cross-section were observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to analyze their crystallographic structures. Electrochemical and immersion tests in Hank’s balanced salt solution were used to analyze their corrosion resistance. Tensile testing was performed with universal testing equipment to investigate the impact of Ca addition. The examination of cytotoxicity for biometric determination was in line with the ISO10993 standard. Results In this study, the 0.1% Ca alloy had significantly retarded grain growth due to the formation of the tiny and well-dispersed Ca2Mg6Zn3 phase. In addition, the yield strength and elongation of the 0.1% Ca alloy were more than 50% greater than the 2% Zn alloy. The limited cell viability of the 0.3% Ca alloy could be attributed to its high corrosion rate, whereas the 0.1% Ca alloy demonstrated cell viability of greater than 80% during the entire experimental period. Conclusion The effect of the addition of Ca on the microstructure, mechanical, and corrosion characteristics of Mg-Zn alloys was analyzed in this work. The findings imply that the Mg-Zn alloy system could be optimized by adding a small amount of Ca, improving mechanical properties while maintaining corrosion rate, thus opening the door to a wide range of applications in orthopedic surgery.

Study Design Retrospective review of prospectively collected cases. Purpose To report bowel injury cases and determine the incidence and risk factors of insidious pneumoperitoneum after lateral lumbar interbody fusion (LLIF). Overview of Literature Minimally invasive LLIF is considered a safe surgical approach with a low risk of complications. Visceral injury after LLIF is rare and, to our knowledge, no studies on pneumoperitoneum after LLIF have been performed. Bowel injury is a catastrophic complication, but the clinical signs may not be apparent. After we encountered two cases of bowel injury after LLIF, we decided to perform computed tomography of the abdomen and pelvis (APCT) after surgery for all patients who underwent LLIF. Methods A total of 90 patients underwent APCT within 48 hours of surgery. Medical records were reviewed to determine each patient’s age, sex, body mass index, medical and surgical histories, characteristics of LLIF procedures, and subjective symptoms and abnormal findings in the physical examination related to acute abdomen after surgery. Various parameters were compared between patients with and without pneumoperitoneum. Results Bowel injuries were identified in the first two patients and five patients (5.5%) were diagnosed with pneumoperitoneum only on APCT. We found that the greater the number of fused segments, the higher the incidence of postoperative bowel injury and/or pneumoperitoneum. The incidence was significantly high when the L2–3 level was included in the LLIF surgery. Conclusions Pneumoperitoneum after LLIF indicates damage to the peritoneum and the presence of bowel injury that may lead to peritonitis. However, it is difficult to distinguish pneumoperitoneum and/or bowel injury from general abdominal pain after surgery because patients may present with a wide range of symptoms. We recommend that APCT be routinely performed after LLIF surgery in order to promptly identify pneumoperitoneum and bowel injury.

Objective To determine whether double transverse incisions could provide superior cosmetic and functional outcomes, including rates of dysphagia and dysphonia, compared with longitudinal incisions in patients undergoing anterior cervical spine surgery (ACSS) involving ≥ 3 levels. Methods A total of 62 consecutive patients who underwent ACSS involving ≥ 3 levels were included in this study. They consist of 33 with longitudinal incisions (L group) and 29 with double transverse incisions (DT group). We recorded functional outcome measures including the Bazaz score for postoperative dysphagia and the Voice Handicap Index-10 (VHI-10) for postoperative dysphonia. The Vancouver Scar Scale (VSS) and the patient and observer scar assessment scale (POSAS) were used to evaluate postoperative skin scarring. Results Cosmetic results, as assessed using the VSS and POSAS, were significantly better in the DT than in the L group at most follow-up time points (p < 0.01 each). Dysphagia rates were significantly lower in the DT group than in the L group during the late postoperative period from 6 months until final 2 years of follow-up (p < 0.01 each). There were no significant different results between the 2 groups in terms of dysphonia. Conclusion A double transverse incision can be a feasible option when performing ACSS involving ≥ 3 levels, providing better cosmesis and lower rates of persistent dysphagia than with a longitudinal incision.

BackgroundThere is a paucity of data on artificial intelligence-estimated biological electrocardiography (ECG) heart age (AI ECG-heart age) for predicting cardiovascular outcomes, distinct from the chronological age (CA). We developed a deep learning-based algorithm to estimate the AI ECG-heart age using standard 12-lead ECGs and evaluated whether it predicted mortality and cardiovascular outcomes.MethodsWe trained and validated a deep neural network using the raw ECG digital data from 425,051 12-lead ECGs acquired between January 2006 and December 2021. The network performed a holdout test using a separate set of 97,058 ECGs. The deep neural network was trained to estimate the AI ECG-heart age [mean absolute error, 5.8 ± 3.9 years; R-squared, 0.7 (r = 0.84, p

A liquid permittivity sensing method is proposed, which is based on measuring the S21 of an on-chip capacitor submerged in a material under test (MUT). The real part of permittivity can be estimated from ɛ′ – |S21| fitted relation in the frequency range of 100 MHz–5 GHz, which are pre-calibrated with four kinds of known materials. The on-chip capacitor is realized with a top metal in a complementary metal oxide semiconductor (CMOS) process, which has an inter-digitized structure featuring a small size of 150 μm × 195 μm. A simple circuit model of the capacitor is used to develop ɛ′ – |S21| relation with a fitting parameter. It shows less than 6.4% root-mean-square (rms) error of ɛ′ for propanol (C3H8O) at 100 MHz–5 GHz.

Objective To introduce a new surgical technique - double dome laminoplasty for decompression of the entire C2 lamina and preservation of an extensor muscle insertion. Methods Eleven consecutive cervical myelopathy patients due to ossification of the posterior longitudinal ligament involving the Axis (C2) area were contained at this study. Direct decompression was evaluated as an increasing rate in space available cord (%) and posterior cord shift (mm) at C2 level. The Japanese Orthopaedic Association (JOA) score, visual analogue scale, and C2–7 Cobb angle in a neutral lateral x-ray were analyzed. Results The mean increase in space available for spinal cord at the C2 level, average posterior cord shift, and JOA recovery rate were 69.7%, 5.3±0.15 mm, and 58.0%, respectively. Cervical lordotic angle was maintained in all patients. One patient reported neck pain (visual analogue scale 6) postoperatively. No specific complications such as C2 laminar fracture or insufficient decompression were observed. Conclusion We recommend double dome laminoplasty for treating patients with cervical myelopathy involving the C2 area to avoid C2 laminectomy, reduce postoperative neck pain, and maintain lordotic cervical spine alignment.

Digital fitness has become a widely used tool for remote exercise guidance, leveraging artificial intelligence to analyze exercise videos and support self-training. This paper introduces a method for self-training in golf, a sport where automated posture analysis can significantly reduce the costs associated with professional coaching. Our system utilizes a pose refinement methodology and an explainable golf swing embedding for analyzing the swing motions of learners and professional golfers. By leveraging sequential coordinate information, we detect biased pose joints and refine the 2D and 3D human pose estimation results. Furthermore, we propose a swing embedding method that considers geometric information extracted from the swing pose. This approach enables not only the comparison of the similarity between two golf swing poses but also the visualization of different points, providing learners with specific and intuitive feedback on areas that require correction. Our experimental results demonstrate the effectiveness of our swing guide system in identifying specific body points that need adjustment to align more closely with a professional golfer’s swing. This research contributes to the digital fitness domain by enhancing the accuracy of posture analysis and providing a specialized and interpretable golf swing analysis system. Our proposed system offers a low-cost and time-efficient approach for users who wish to improve their golf swing, paving the way for broader applications of digital fitness technologies in self-training contexts.

Abstract Background Although the original technique involves inserting two cages bilaterally, there could be situations that only allow for insertion of one cage unilaterally. However, only a few studies have compared the outcomes between unilateral and bilateral cage insertion. The purpose of this study was to compare the clinical and radiological outcomes in patients who underwent posterior lumbar interbody fusion (PLIF) between unilaterally and bilaterally inserted cages. Methods Among 206 eligible patients who underwent 1- or 2-level PLIF, 78 patients were 1:3 cohort-matched by age, sex, and operation level (group U, 19 patients with unilateral cages; and group B, 57 patients with bilateral cages). Fusion status was evaluated by computed tomography (CT) scans at postoperative 1 year. Clinical outcomes were measured by visual analog scale (VAS), Oswestry Disability Index (ODI), and EQ-5D. Radiological and clinical parameters were compared between the two groups. Risk factors for pseudarthrosis were also analyzed by multivariate analysis. Results The demographic data were not significantly different between the two groups. However, previous laminectomy, asymmetric disc collapse, and fusion at L5-S1 level were more frequently found in group U (P = 0.003, P = 0.014, and P = 0.014, respectively). Furthermore, pseudarthrosis was more frequently observed in group U (36.8%) than in group B (7.0%) (P = 0.004). Back pain VAS was higher in group U at postoperative 1 year (P = 0.033). Lower general activity function of EQ-5D was observed in group U at postoperative 1 year (P = 0.035). Older age (P = 0.028), unilateral cage (P = 0.007), and higher bone mineral density (P = 0.033) were positively correlated with pseudarthrosis. Conclusions Unilaterally inserted cage might be a possible risk factor for pseudarthrosis when performing PLIF, which could be related with the difficult working conditions such as scars due to previous laminectomy or asymmetric disc collapse. Furthermore, suboptimal clinical outcomes are expected following PLIF with unilateral cage insertion at postoperative 1 year regardless of similar clinical outcomes at postoperative 2 year. Therefore, caution is advised when inserting cages unilaterally, especially under above-mentioned conditions in terms of its possible relationship with symptomatic pseudarthrosis.

This study was conducted to evaluate the effects of a toy on the behaviour and body weight of weaned pigs after mixing. Two groups (192 pigs in total, control: without toy; treatment: with toy placed on the floor) of weaned pigs housed in pens (1.8 m × 1.4 m, 4 pigs/pen) were This study was conducted to evaluate the effects of a toy on the behaviour and body weight of weaned pigs after mixing. Two were observed with the aid of video technology for nine consecutive hours in the early (days 1 and 2) and late (days 38 and 39) period after mixing. Bodyweight of pigs at the end of the study (Mann-Whitney U-test, Z = -2.46, P = 0.01) and the average daily gain (Z = -2.75, P < 0.01) were 10% higher in the treatment group than in the control group. The presence of the toy in the pen influenced the pig behaviours. In pens enriched with toys, there was an increase in feeding behaviour and a decrease in agonistic and belly nosing behaviours. Toy supply reduced negative social behaviours and thereby improved the bodyweight of weaned pigs. The results of this study suggest that toys used as environmental enrichment are useful for enhancing pig welfare and effective for farmers.

Abstract This study aimed to evaluate the subclinical gait abnormalities and the postoperative gait improvements in patients with degenerative cervical myelopathy using three-dimensional gait analysis. We reviewed the gait analysis of 62 patients who underwent surgical treatment for degenerative cervical myelopathy. The asymptomatic gait group included 30 patients and the gait disturbance group included 32 patients who can walk on their own slowly or need assistive device on stairs. The step width (17.2 cm vs. 15.9 cm, P = 0.003), stride length (105.2 cm vs. 109.1 cm, P = 0.015), and double-limb support duration (13.4% vs. 11.7%, P = 0.027) improved only in the asymptomatic gait group. Preoperatively, the asymptomatic gait group exhibited better maximum knee flexion angle (60.5° vs. 54.8°, P = 0.001) and ankle plantarflexion angle at push-off (− 12.2° vs. − 6.5°, P = 0.001) compared to the gait disturbance group. Postoperatively, maximum knee flexion angle (62.3° vs. 58.2°, P = 0.004) and ankle plantarflexion angle at push-off (− 12.8° vs. − 8.3°, P = 0.002) were still better in the asymptomatic gait group, although both parameters improved in the gait disturbance group (P = 0.005, 0.039, respectively). Kinematic parameters could improve in patients with gait disturbance. However, temporospatial parameters improvement may be expected when the operative treatment is performed before apparent gait disturbance.

A novel approximation-free differentiator-based output-feedback controller for uncertain large-scale systems (LSSs) is proposed. The considered LSS has nonautonomous and nonaffine-in-the-control subsystems which is yet to be tackled for decentralized output-feedback controller in the previous researches. The controller adopts a higher-order switching differentiator that can track the time-derivatives of a time-varying signal asymptotically. Through the differentiators, time-derivatives of output tracking errors are estimated and unstructured uncertainties in the controlled subsystems are compensated. The proposed decentralized output-feedback control formulae and the stability analysis are relatively simple in comparison to the previously proposed decentralized controllers. In this case, approximators such as fuzzy systems or neural networks are not required. The proposed controller guarantees that the tracking errors of the subsystems are asymptotically convergent to zeros and all the signals involved in the closed-loop systems are bounded.

Cervical spondylotic myelopathy is surgically demanding when associated with rigid kyphosis. Posterior surgery cannot restore cervical lordosis, and adequate decompression is not possible with rigid kyphosis. Vertebral body sliding osteotomy (VBSO) is a safe and novel technique for anterior decompression in patients with multilevel cervical spondylotic myelopathy. It is safe in terms of dural tear, pseudarthrosis, and graft dislodgement, which are demonstrated at high rates in anterior cervical corpectomy and fusion. In addition, VBSO is a powerful method for restoring cervical lordosis through multilevel anterior cervical discectomy and fusion above and below the osteotomy level. It may be a feasible treatment option for patients with cervical spondylotic myelopathy and kyphotic deformity. This is a technical note and literature review that describes the procedures involved in VBSO.

Study Design Retrospective case analyses. Purpose To investigate the causes, diagnosis, and management of esophageal perforation, depending on the time of diagnosis. Overview of Literature To date, few studies have addressed these issues. Methods A total of seven patients were included in this study. The patients were classified into three groups based on esophageal perforation diagnosis time: intraoperative (diagnosed during surgery), perioperative (diagnosed within 30 days postoperatively), and delayed (diagnosed >30 days postoperatively) groups. Results In the intraoperative group (N=2), infectious spondylitis was the main cause of esophageal perforation. Anterior plate and screw removal, followed by posterior instrumentation, was performed. The injured esophagus was managed by omentum flap repair in one patient and primary repair in one patient. In the perioperative group (N=2), revision surgery for infection and metal failure were the main causes of esophageal perforation. In both cases, food residue was drained on the third postoperative day. The injured esophagus was managed conservatively. In the delayed group (N=3), chronic irritation caused by metal failure was the main cause of esophageal perforation. In all patients, there was no associated infection. The anterior instrumentation was removed, and the two patients were treated by primary repair, and one patient was treated using sternocleidomastoid muscle flap. One patient in intraoperative group died of sepsis. Conclusions The main cause of intraoperative esophageal perforation was esophageal adhesions because of infectious spondylitis. However, perioperative and delayed esophageal perforations were caused by chronic irritation because of metal failure. Anterior plate and screw removal was necessary, and posterior instrumentation and fusion may be considered, depending on the fusion status.

Abstract Nonhuman primate models are valuable in biomedical research. However, reference data for clinical pathology parameters in cynomolgus and rhesus monkeys are limited. In the present study, we established hematologic and biochemical reference intervals for healthy cynomolgus and rhesus monkeys anesthetized with ketamine hydrochloride. A total of 142 cynomolgus monkeys (28 males and 114 females) and 42 rhesus monkeys (22 males and 20 females) were selected and analyzed in order to examine reference intervals of 20 hematological and 16 biochemical parameters. The effects of sex were also investigated. Reference intervals for hematological and biochemical parameters were separately established by species (cynomolgus and rhesus) and sex (male and female). No sex-related differences were determined in erythrocyte-related parameters for cynomolgus and rhesus monkey housed in indoor laboratory conditions. Alkaline phosphatase and gamma glutamyltransferase were significantly lower in females than males in both cynomolgus and rhesus monkeys aged 48–96 months. The reference values for hematological and biochemical parameters established herein might provide valuable information for researchers using cynomolgus and rhesus monkeys in experimental conditions for biomedical studies.

In laser-plasma interactions (LPI), the laser beam mode is a critical parameter when trying to explore new physical phenomena. Of the various spatial beam modes, the Laguerre-Gaussian (LG) mode with vortex phase has attracted considerable attention due to its unique features, including the ability to carry an orbital angular momentum. Due to this, it has been actively applied to LPI, which mainly utilize ultrashort intense laser pulses. However, existing transmissive phase-manipulating optical elements have several limitations when applied in LPI due to critical issues such as pulse broadening, attenuation, and beam shape–all of which have an influence on the beam quality, as well as, geometry, size, simplicity, and cost–all of which are related to processing technologies. In this paper, we present a series of procedures to obtain high-quality low-order (l = 1 and 2) LG vortex beams from large-sized off-axis reflective spiral phase plates (ORSPPs). The geometric designs for various surface structures, electromagnetic wave simulations in the extra-large domain, hybrid-mechanical processing technique attempted newly, and experimental demonstrations are involved. Experimental observations of LG intensity distributions and interference fringes were verified with the simulation results of Poynting vector, phase, and angular momentum densities. The beam quality of LG intensity distributions was analyzed quantitatively through the investigation of an annular zone formed from the uniformity of the stepped and continuous surface structures of ORSPPs. Furthermore, we numerically investigated the physical phenomena on the high-intensity angular momentum transfer from light to matter, considering ORSPP–driven low-order LG vortex laser pulses, by performing 3D particle-in-cell simulations.

Particulate matter (PM) is a general atmospheric pollutant released into the air by an anthropogenic and naturally derived mixture of substances. Current studies indicate that fine dust can result in different health defects, including endothelial dysfunction, asthma, lung cancer, cardiovascular diseases, uterine leiomyoma, deterioration in sperm quality, and overall birth impairment. However, the most prominent effects of PM10 (diameter < 10 μM) exposure on the female reproductive system, especially with respect to oocyte maturation, remain unclear. In the present study, maturing mouse oocytes were treated with PM10 and the phenotypes of the resulting toxic effects were investigated. Exposure to PM10 led to impairment of maturation capacity by inducing cell cycle arrest and blocking normal polar body extrusion during in vitro maturation and activation of fertilization of mouse oocytes. Additionally, defects in tubulin formation and DNA alignment were observed in PM10-treated oocytes during metaphase I to anaphase/telophase I transition. Moreover, PM10 induced reactive oxygen species generation, mitochondrial dysfunction, DNA damage, and early apoptosis. Taken together, these results indicate that PM10 exposure leads to a decline in oocyte quality and affects the subsequent embryonic development potential of mammalian oocytes.

Chungkookjang is a beneficial fermented soybean food with anticancer, anti-inflammatory, and antioxidant activities. High oleic acid (HO)-containing diets are known to help in preventing cardiovascular disease (CVD). In the present study, we assessed functional quality characteristics of Chungkookjang made from soybean seeds differing in oleic acid concentration. Chungkookjang made from HO and normal oleic acid (NO) soybeans did not differ significantly in moisture content, pH, viable cell number, protease activity, amino type nitrogen, and polyphenol activity. However, the diphenylpicrylhydrazyl (DPPH)-scavenging activity and flavonoid contents of Chungkookjang made from HO soybeans were lower than those from NO soybeans. The oleic acid concentrations were not significantly altered by fermentation. Additionally, Chungkookjang from the HO soybean cultivar ‘Hosim’ affected the vascular relaxation of endothelium-intact rat aortic rings at concentrations as low as 0.03 mg/mL. The results showed that Chungkookjang from HO soybeans possesses characteristics that might be potentially helpful in reducing the risk of CVD.

Growing interest in healthcare has promoted the use of symptom checkers, which are online health applications that provide diagnostic information on users' health. However, their diagnostic accuracy remains low because the existing symptom checkers rely on manually constructed knowledge models through labor-intensive processes or perform diagnoses based on simple pairwise relationships between diseases and symptoms without considering personal health conditions. In this paper, we propose an intelligent health diagnosis technique that exploits automatically generated ontology and Web-based personal health record services. The proposed technique first automatically generates a human disease diagnosis ontology by exploiting two well-established ontologies for diseases and symptoms: a large-scale medical bibliographic database and an open biomedical repository. When a user enters the symptom-based queries, possible diagnoses are identified by analyzing the user's queries and their health record data via semantic inferences of the automatically generated ontology. Subsequently, the ranked diagnostic results are provided to the user via ranking methods that consider the user's symptoms, personal health attributes, and multi-level diagnosis. The proposed technique also provides the user's diagnostic progress information, which can be used to track or monitor the progress of diseases by considering changes in symptoms over time. The proposed technique was evaluated through a comparison with the existing well-known symptom checkers and other related approaches. The evaluation results show that the proposed technique can feasibly help to improve diagnostic accuracy and deliver appropriate diagnostic information for healthcare action by users.

Common quantum algorithms make heavy use of ancillae: scratch qubits that are initialized at some state and later returned to that state and discarded. Existing quantum circuit languages let programmers assert that a qubit has been returned to the |0> state before it is discarded, allowing for a range of optimizations. However, existing languages do not provide the tools to verify these assertions, introducing a potential source of errors. In this paper we present methods for verifying that ancillae are discarded in the desired state, and use these methods to implement a verified compiler from classical functions to quantum oracles.

This paper presents an image interpolation method that provides superior performance with low complexity. Applying a simple linear method achieves time-efficient interpolation, but often produces artifacts; however, applying other complex methods reduce unwanted artifacts at the cost of high computation time. The proposed interpolation scheme is based on the improvement of an algorithm called “Edge Slope Tracing (EST)” that predicts the slope based on the information of the adjacent slopes. Predicted slopes are used in slope-based line averaging to perform the interpolation. Slope-based line averaging is followed by post-processing of an interpolated image using two-way interpolation and thin edge correction to avoid the production of unwanted artifacts at the cost of low complexity. The proposed algorithm is very simple and simulation results indicate that it provides better or nearly equal results compared to conventional state-of-the-art algorithms and that it also reduces complexity to a great extent compared to conventional methods.

With an increase in the size and shape complexity of optical surfaces, the periodic structure on the optical surface can have significant effects on the beam profile, which propagates in the optical system. This necessitates a quantitative analysis of the interference between diffracted beam modes formed on the propagating beam profile after the reflection on the optical surfaces with periodic structures. Herein, a generalized equation, which determines the period of the constructive interference formed by Bragg scattering, is presented for the only two diffracted beam modes given by the mth and nth order. Two theoretical calculations, one being an analytical calculation based on the interference equation, and the other being a numerical simulation based on Fourier optics, are conducted for all the diffracted beam modes to reflect the effects of higher-order diffraction. Furthermore, the simulation results based on the Fourier optics are much closer to real phenomena because the boundary conditions are exactly considered. As the aspect ratio of the periodic structure on the optical surface increases, the period of constructive interference decreases, and its intensity is remarkably increased from the two theoretical calculations. Our results will be extensively applied as a novel theoretical tool to analyze quantitatively the effects of periodic structures on the propagating beam profile by providing a deep understanding about the interference formed by Bragg scattering.

Cultivation soil is the basis for cabbage growth, and it is important to assess not only to provide information on how it affects the growth of vegetable crops but also for cultivation management. Until now, field cabbage surveys have measured size and growth variations in the field, and this method requires a lot of time and effort. Drones and sensors provide opportunities to accurately capture and utilize cabbage growth and variation data. This study aims to determine the growth stages based on drone remote estimation of the cabbage height and evaluate the impact of the soil texture on cabbage height. Time series variation according to the growth of Kimchi cabbage exhibits an S-shaped sigmoid curve. The logistic model of the growth curve indicates the height and growth variation of Kimchi cabbage, and the growth rate and growth acceleration formula of Kimchi cabbage can thus be derived. The curvature of the growth parameter can be used to identify variations in Kimchi cabbage height and its stages of growth. The main research results are as follows. (1) According to the growth curve, Kimchi cabbage growth can be divided into four stages: initial slow growth stage (seedling), growth acceleration stage (transplant and cupping), heading through slow growth, and final maturity. The three boundary points of the Kimchi cabbage growth curve are 0.2113 Gmax, 0.5 Gmax, and 0.7887 Gmax, where Gmax is the maximum height of Kimchi cabbage. The growth rate of cabbage reaches its peak at 0.5 Gmax. The growth acceleration of cabbage forms inflection points at 0.2113 Gmax and 0.7887 Gmax, and shows a variation characteristic. (2) The produced logistic growth model expresses the variation in the cabbage surface model value for each date of cabbage observation under each soil texture condition, with a high degree of accuracy. The accuracy evaluation showed that R2 was at least 0.89, and the normalized root-mean-square error (nRMSE) was 0.09 for clay loam, 0.06 for loam, and 0.07 for sandy loam, indicating a very strong regression relationship. It can be concluded that the logistic model is an important model for the phase division of cabbage growth and height variation based on cabbage growth parameters. The results obtained in this study provide a new method for understanding the characteristics and mechanisms of the growth phase transition of cabbage, and this study will be useful in the future to extract various types of information using drones and sensors from field vegetable crops.

Abstract A new impulsive noise removal filter, adaptive dynamically weighted median filter (ADWMF), is proposed. A popular method for removing impulsive noise is a median filter whereas the weighted median filter and center weighted median filter were also investigated. ADWMF is based on weighted median filter. In ADWMF, instead of fixed weights, weightages of the filter are dynamically assigned with the results of noise detection. A simple and efficient noise detection method is also used to detect noise candidates and dynamically assign zero or small weights to the noise candidates in the window. This paper proposes an adaptive method which increases the window size according to the amounts of impulsive noise. Simulation results show that the AMWMF works better for both images with low and high density of impulsive noise than existing methods work.

South Korea’s agriculture is characterized by a mixture of various cultivated crops. In such an agricultural environment, convergence technology for ICT (information, communications, and technology) and AI (artificial intelligence) as well as agriculture is required to classify objects and predict yields. In general, the classification of paddy fields and field boundaries takes a lot of time and effort. The Farm Map was developed to clearly demarcate and classify the boundaries of paddy fields and fields in Korea. Therefore, this study tried to minimize the time and effort required to divide paddy fields and fields through the application of the Farm Map. To improve the fact that UAV image processing for a wide area requires a lot of time and effort to classify objects, we suggest a method for optimizing cultivated crop recognition. This study aimed to evaluate the applicability and effectiveness of machine learning classification techniques using a Farm Map in object-based mapping of agricultural land using unmanned aerial vehicles (UAVs). In this study, the advanced function selection method for object classification is to improve classification accuracy by using two types of classifiers, support vector machine (SVM) and random forest (RF). As a result of classification by applying a Farm Map-based SVM algorithm to wide-area UAV images, producer’s accuracy (PA) was 81.68%, user’s accuracy (UA) was 75.09%, the Kappa coefficient was 0.77, and the F-measure was 0.78. The results of classification by the Farm Map-based RF algorithm were as follows: PA of 96.58%, UA of 92.27%, a Kappa coefficient of 0.94, and the F-measure of 0.94. In the cultivation environment in which various crops were mixed, the corn cultivation area was estimated to be 96.54 ha by SVM, showing an accuracy of 90.27%. RF provided an estimate of 98.77 ha and showed an accuracy of 92.36%, which was higher than that of SVM. As a result of using the Farm Map for the object-based classification method, the agricultural land classification showed a higher efficiency in terms of time than the existing object classification method. Most importantly, it was confirmed that the efficiency of data processing can be increased by minimizing the possibility of misclassification in the obtained results. The obtained results confirmed that rapid and reliable analysis is possible when the cultivated area of crops is identified using UAV images, a Farm Map, and machine learning.

Study DesignRetrospective case series.PurposeThe purpose of this study was to examine the incidence of neural axis abnormalities and the relevant risk factors in patients with adolescent idiopathic scoliosis (AIS).Overview of LiteratureThe use of preoperative magnetic resonance imaging (MRI) to assess the whole spine in patients with idiopathic scoliosis is controversial, and indications for such MRI evaluations have not been definitively established. However, we routinely use whole-spine MRI in patients with scoliosis who are scheduled to undergo surgical correction.MethodsA total of 378 consecutive patients with presumed AIS who were admitted for spinal surgery were examined for neural axis abnormalities using MRI. To differentiate patients with normal and abnormal MRI findings, the following clinical parameters were evaluated: age, sex, menarcheal status, rotation angle (using a scoliometer), coronal balance, shoulder height difference, and low back pain. We radiographically evaluated curve type, thoracic or thoracolumbar curve direction, curve magnitude and flexibility, apical vertebral rotation, curve length, coronal balance, sagittal balance, shoulder height difference, thoracic kyphosis, and the Risser sign.ResultsNeural axis abnormalities were detected in 24 patients (6.3%). Abnormal MRI findings were significantly more common in males than in females and were associated with increased thoracic kyphosis. However, there were no significant differences in terms of the other measured parameters.ConclusionsAmong the patients with presumed AIS who received preoperative whole-spine MRI, 6.3% had neural axis abnormalities. Males and patients with increased thoracic kyphosis were at a higher risk.

Objective: We investigated causes and results of revision surgeries after artificial disc replacement of cervical spine (C-ADR). Methods: Twenty-one patients (mean age: 52.8) who underwent revision surgery after C-ADR and who had a minimum 2-year of follow-up were included into this study. The mean time between the primary and revision surgeries was 21 months. During their primary surgeries, 14 patients underwent single level C-ADR, 2 two-level C-ADR, and 5 two-level hybrid surgery for 16 radiculopathy, 3 myelopathy, and 2 adjacent segment diseases. Causes for revision surgeries were at least one of the followings: 17 poor patient selections, 7 insufficient decompressions, 7 malpositions, 6 subsidences, 3 osteolysis, and 1 postoperative infection. Results: Sixteen patients underwent anterior removal of C-ADR, one-level discectomy and fusion (N = 11), two-level discectomy (N = 3) or one-level corpectomy (N = 2) and fusion. Three patients of keel type C-ADR with heterotopic ossification underwent posterior laminoforaminotomy and fusion. Two patients underwent combined procedures due to infection or severe subsidence and osteolysis. At the 2-year follow-up, neck (7.3 vs 1.6) and arm (7.0 vs 1.3) visual analog scales and Neck Disability Index score (46.7 vs 16.32) were improved (all, p

Study DesignSurvey based study.PurposeTo assess the degree of agreement in level selection of laminoplasty (LP) for the selected cervical myeloradiculopathy cases between experienced spine surgeons.Overview of LiteratureAlthough, cervical LP is a widely used surgical technique for multi-level spinal cord compression, until now there is no consensus about how many segments or which segments should be opened to achieve a satisfactory decompression.MethodsThorough clinical and radiographic data (plain X-ray, computed tomography, and magnetic resonance imaging) of 30 patients who had cervical myelopathy were prepared. The data were provided to three independent spine surgeons with over 10 years experience in operation of their own practices. They were questioned about the most preferable surgical method and suitable decompression levels. The second survey was carried out after 6 months with the same cases. If the level difference between respondents was a half level or below, agreement was considered acceptable. The intraobserver and interobserver agreements in level selection were assessed by kappa statistics.ResultsThree respondents selected LP as an option for 6, 8, and 22 cases in the first survey and 10, 21, and 24 cases in the second survey. The reasons for selection of LP were levels of ossification of the posterior longitudinal ligament (p=0.004), segmental kyphotic deformity (p=0.036) and mean compression score (p=0.041). Intraobserver agreement showed variable results. Interobserver agreement was poor to fair by perfect matching (kappa=0.111–0.304) and fair to moderate by acceptable matching (kappa=0.308–0.625).ConclusionsThe degree of agreement for level selection of LP was not high even though experienced surgeons would choose the opening segments on the basis of same criteria. These results suggest that more specific guidelines in determination of levels for LP should be required to decrease unnecessary wide decompression according to individual variance.

Kimchi cabbage grows in South Korea and is an essential ingredient for making kimchi with the kimjang method. The technique of accurately managing and monitoring crops such as kimchi cabbage plays an important role in stabilizing consumer prices. Unmanned aerial vehicles (UAVs) are expected to be used more widely in global and local agriculture. The agricultural sites at which kimchi cabbages are cultivated are affected by various climatic, terrain, and soil conditions, requiring technologies that can accurately and quickly acquire such information. UAVs and sensors are able to provide some of these data. In this study, we set up a cultivation environment for kimchi cabbage and investigated the correlation between a UAV-attached multispectral sensor and a field-portable spectroradiometer. Reflectance measurement using a spectroradiometer was performed on 99 kimchi cabbages in a Mt. Maebong testbed. We aimed to find a method for obtaining accurate vegetation information by combining the high spatial and temporal resolution information of the UAV observation with the spectral resolution of the spectroradiometer. Spectral analysis was used to identify the difference between healthy and poorly growing cabbage and to find the wavelength that most affected the growth. The hyperspectrum of the spectroradiometer reflected the accurate vegetation characteristics and contributed greatly to the identification of vegetation indices. A method for correcting the errors that occurred in the ground and UAV monitoring and the difference arising from the application of the broadband wavelength of the UAV and the single wavelength of the spectroradiometer through correlation analysis is presented. The calibration equation method was applied to UAV spatial information and was used to create a precise normalized distribution vegetation index (p-NDVI) map. The p-NDVI map was organized into four categories for the selection of cabbages with healthy (good) growth. Our results show that (1) the merged spectral analysis method was found to be more accurate and distinct than conventional methods, and (2) methods for estimating cabbage growth status showed a higher significant correlation than the UAV-based NDVI. At the maturity stage, high accuracy (R2 = 0.7816, RMSE = 0.06) was achieved for NDVI. Although this map is the result of the limited vegetation monitoring of UAV images taken during the maturity stage, it could be of great help for managing the quality and production of cabbage. However, the efficient management of highland kimchi cabbage requires continuous research under various conditions to enable periodic and systematic monitoring using UAVs and sensors.