A Study on Frame Prediction Method based on Operation Probability Map

동영상내에서 손상에 의해 소실된 프레임을 복원하거나 연속적인 새로운 프레임을 생성하는 기법인 프레임 예측은 객체들의 동작 예측이 필요한 자율주행, 보안 등의 미래 주요 기술로서 주목받고 있다. 최근 이 기술은 딥러닝 기술과 결합하여 예측 정확도가 많이 향상되고 있으나 많은 학습데이터와 연산량이 수반되기 때문에 실질적인 적용에는 어려움이 존재한다. 기존의 딥러닝 기반 예측 모델은 새로운 프레임 생성 과정에서 예측에 의해 생성된 프레임을 피드백하기 때문에 누적오차가 많이 발생하여 시간이 지남에 따라 예측 정확도가 감소한다. 따라서 본 논문에서는 convolution neural network (CNN)와 long short-term memory (LSTM)으로 구성된 네트워크를 통해 프레임들의 동작 특징들을 추출하고 패턴을 학습하여 동작 확률 지도를 생성하여 움직임이 발생한 영역에 대하여 deconvolution neural network(DNN)를 통해 이후 프레임을 생성하는 새로운 프레임 예측 모델을 제안한다. 제안한 모델은 CNN과 LSTM을 통해 프레임들의 동작 특징들을 추출하고 패턴을 학습하여 동작 확률 지도를 생성한다. 이를 통해 임의의 한 프레임에서 동작이 발생하는 영역를 판별하고 이 영역만 DNN을 통해 새로운 프레임을 획득한다. 이때 학습 난이도가 높은 DNN의 효율적인 학습을 위해 generative adversarial nets(GAN) 기법을 적용한다. 제안된 새로운 모델의 학습과 검증을 위하여 무작위로 일부 프레임이 제거된 로봇 움직임 영상을 기반으로 생성된 영상과 원본 영상을 PSNR로 비교 분석하였다. 그 결과, 제안한 프레임 예측 모델의 PSNR은 35.16으로 비교한 3개의 다른 모델에 비해 최대 14.06이 향상되었다. 또한 생성된 프레임에 따른 PSNR의 감소도 4번째 프레임 이전에는 2, 이후에는 7로 평균 5가 개선되었다.|Frame prediction, which is a technique to reconstruct frames lost due to damage or to generate new consecutive frames in the video, is attracting attention as a main technology which is indispensable for the autonomous vehicle and the artificial intelligence based security system that require motion prediction of objects. Recently, this technology has improved prediction accuracy in combination with deep learning technology, but it is difficulties in practical application because it involves a lot of learning data and computation amount. The existing deep learning based prediction model, since the frame generated by the prediction is feedback in the new frame generation process, is decreased the prediction accuracy over time. Therefore, in this paper, we propose an operation probability map based new frame prediction model using convolution neural network (CNN), long short-term, memory (LSTM) and deconvolution neural network(DNN) to minimize unnecessary computation regions in the frame and prediction error. The proposed model extracts the operating characteristics of the frames through CNN and LSTM and learns the patterns to generate the operation probability map. Through this process, a region in which an operation occurs is determined in one frame, and a new frame is obtained through DNN only in this region. At this time, the generative adversarial nets(GAN) technique is applied for efficient learning of DNN with the high learning complexity. For the learning and verification of the proposed new model, we compared and analyzed the generated frame and the original frame based on robotic motion images with some frames removed randomly using PSNR. As a result, the PSNR of the proposed frame prediction model is 35.16, which is 14.06 higher than the other three models. Also, the decrease of the PSNR according to the generated frame is decreased to 2 before the 4th frame and then to 7 thereafter, and is improved by 5 on the average.Chapter 1 Introduction 01 Chapter 2 Related Works 06 2.1 Convolution Neural Network 06 2.2 Long Short-Term Memory 09 2.3 Generative Adversarial Nets 12 Chapter 3 The Proposed Prediction Model 15 3.1 Structure of the proposed model 17 3.2 Model for feature extraction and operation probability estimation 21 3.3 Model for generating and combining images 24 3.4 Model for learning of generative model 27 Chapter 4 Experiment and Result 29 4.1 Dataset for learning and testing 29 4.2 Analysis of experimental results 30 Chapter 5 Conclusion 37 Reference 38Maste

Awakening in extracorporeal membrane oxygenation as a bridge to lung transplantation

Although the rate of lung transplantation (LTx), the last treatment option for end-stage lung disease, is increasing, some patients waiting for LTx need a bridging strategy for LTx due to the limited number of available donor lungs. For a long time, mechanical ventilation has been employed as a bridge to LTx because the outcome of using extracorporeal membrane oxygenation (ECMO) as a bridging strategy has been poor. However, the outcome after mechanical ventilation as a bridge to LTx was poor compared with that in patients without bridges. With advances in technology and the accumulation of experience, the outcome of ECMO as a bridge to LTx has improved, and the rate of ECMO use as a bridging strategy has increased over time. However, whether the use of ECMO as a bridge to LTx can achieve survival rates similar to those of non-bridged LTx patients remains controversial. In 2010, one center introduced awake ECMO strategy for LTx bridging, and its use as a bridge to LTx has been showing favorable outcomes to date. Awake ECMO has several advantages, such as maintenance of physical activity, spontaneous breathing, avoidance of endotracheal intubation, and reduced use of sedatives and analgesics, but it may cause serious problems. Nonetheless, several studies have shown that awake ECMO performed by a multidisciplinary team is safe. In cases where ECMO or mechanical ventilation is required due to unavoidable exacerbation in patients awaiting LTx, the application of awake ECMO performed by an appropriately trained ECMO multi-disciplinary team can be useful.ope

Early short course of neuromuscular blocking agents in patients with COVID-19 ARDS: a propensity score analysis

Background: The role of neuromuscular blocking agents (NMBAs) in coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) is not fully elucidated. Therefore, we aimed to investigate in COVID-19 patients with moderate-to-severe ARDS the impact of early use of NMBAs on 90-day mortality, through propensity score (PS) matching analysis. Methods: We analyzed a convenience sample of patients with COVID-19 and moderate-to-severe ARDS, admitted to 244 intensive care units within the COVID-19 Critical Care Consortium, from February 1, 2020, through October 31, 2021. Patients undergoing at least 2 days and up to 3 consecutive days of NMBAs (NMBA treatment), within 48 h from commencement of IMV were compared with subjects who did not receive NMBAs or only upon commencement of IMV (control). The primary objective in the PS-matched cohort was comparison between groups in 90-day in-hospital mortality, assessed through Cox proportional hazard modeling. Secondary objectives were comparisons in the numbers of ventilator-free days (VFD) between day 1 and day 28 and between day 1 and 90 through competing risk regression. Results: Data from 1953 patients were included. After propensity score matching, 210 cases from each group were well matched. In the PS-matched cohort, mean (± SD) age was 60.3 ± 13.2 years and 296 (70.5%) were male and the most common comorbidities were hypertension (56.9%), obesity (41.1%), and diabetes (30.0%). The unadjusted hazard ratio (HR) for death at 90 days in the NMBA treatment vs control group was 1.12 (95% CI 0.79, 1.59, p = 0.534). After adjustment for smoking habit and critical therapeutic covariates, the HR was 1.07 (95% CI 0.72, 1.61, p = 0.729). At 28 days, VFD were 16 (IQR 0-25) and 25 (IQR 7-26) in the NMBA treatment and control groups, respectively (sub-hazard ratio 0.82, 95% CI 0.67, 1.00, p = 0.055). At 90 days, VFD were 77 (IQR 0-87) and 87 (IQR 0-88) (sub-hazard ratio 0.86 (95% CI 0.69, 1.07; p = 0.177). Conclusions: In patients with COVID-19 and moderate-to-severe ARDS, short course of NMBA treatment, applied early, did not significantly improve 90-day mortality and VFD. In the absence of definitive data from clinical trials, NMBAs should be indicated cautiously in this setting.ope

Hemoptysis requiring bronchial artery embolization in patients with nontuberculous mycobacterial lung disease

BACKGROUND: Although infections caused by nontuberculous mycobacteria (NTM) are increasing in prevalence, there are few data about hemoptysis in patients with NTM lung disease. This study investigated the characteristics and prognosis of hemoptysis secondary to NTM infection. METHODS: Following a retrospective review of cases managed between 2006 and 2016, 183 patients with NTM lung disease were enrolled and analyzed. RESULTS: Among 183 patients with NTM lung disease, Mycobacterium intracellulare (n = 64, 35%) was the major cause of NTM infection, followed by M. avium (n = 59, 32.2%) and M. abscessus complex (n = 40, 21.9%). Hemoptysis developed in 78 patients (42.6%), among whom 33 (42.3%) required bronchial artery embolization (BAE). Between patients with and without hemoptysis, there were no significant differences with respect to sex, radiographic manifestations, distribution over 3 lobes on chest computed tomography, history of pulmonary tuberculosis, antiplatelet or anticoagulation therapy, and species of NTM. However, mean age at diagnosis was significantly lower in the hemoptysis group in univariate and multivariate analyses (65.7 ± 12.8 vs. 59.7 ± 11.8, P = 0.002, odds ratio: 0.969, 95% confidence interval: 0.944-0.996). Among patients with hemoptysis, those requiring medical therapy and those requiring BAE were not significantly different in terms of demographic characteristics, radiographic manifestations, and distribution over 3 lobes. All patients who received BAE showed immediate clinical improvement, no procedure-related complications, and none of them died during the period under review. CONCLUSIONS: NTM lung disease patients commonly experienced hemoptysis without specific risk factors except for relatively young age. Although some patients with hemoptysis needed BAE, the success rate of BAE was high, and there were no serious complications associated with BAE.ope

The Relationship between Platelet Count and Host Gut Microbiota: A Population-Based Retrospective Cross-Sectional Study

Platelet count reflects the severity and prognosis of multiple diseases. Additionally, alterations in gut microbiota have been linked to several chronic diseases. The purpose of this study was to investigate the association between gut microbiota and platelet count. We selected 1268 subjects with fecal 16S RNA gene sequencing data from a Healthcare Screening Center cohort. Based on the third quartile of platelets (277 × 10⁸/L), we compared the gut microbiota between the upper quartile (n = 321) and lower three quartiles groups (n = 947). The upper quartile group had lower alpha diversity based on observed amplicon sequence variants (q = 0.004) and phylogenetic index (q < 0.001) than the lower three quartiles group. Significant differences were also found in the weighted UniFrac distance (q = 0.001) and Jaccard dissimilarity (q = 0.047) beta diversity measures between the two groups. Compared with the lower three quartiles group, the upper quartile group exhibited decreased relative abundances of the genus Faecalibacterium, which was also inversely correlated with the platelet count. Increased platelet count was associated with reduced diversity in gut microbiota and lower abundances of Faecalibacterium with beneficial gut bacteria spices F. prausnitzii, suggesting that an increased platelet count, even within normal range, may adversely affect gut microbial diversity and composition.ope

Impact of right ventricular systolic pressure in elderly patients admitted to intensive care unit after femur fracture surgery: A retrospective observational study

The number of femoral fractures is expected to continue to increase as the size of the older population rapidly grows. However, old age is accompanied by various comorbidities and is an important postoperative risk factor in itself, meaning that patients who undergo surgery for a femur fracture may require admission to an ICU. We investigated pulmonary complications in patients over the age of 65 admitted to the ICU after femur fracture surgery.In this single-center retrospective observational study, 289 patients over 65 years who admitted to the ICU after femur fracture surgery between June 2008 and December 2016 were investigated.Pulmonary complications occurred in 97 of these patients (33.6%) after surgery. Mean hospitalization days (34.1 ± 25.7 vs 23.1 ± 15.7, P 35 mm Hg, which is a marker for pulmonary hypertension (55.2% vs 76.3% for patients without and with pulmonary complications, P 35 mm Hg during preoperative echocardiography was associated with pulmonary complications after femur fracture surgery (OR, 2.6; 95% CI, 1.45-4.53).In conclusion, Pulmonary complications in older patients admitted to the ICU after femur fracture surgery was associated with longer hospitalization and ICU stays. Preoperative RVSP measurement could identify those older patients with a high risk of pulmonary complications following transferal to the ICU after femur fracture surgery.ope

The Profile of Early Sedation Depth and Clinical Outcomes of Mechanically Ventilated Patients in Korea

Background: Current international guidelines recommend against deep sedation as it is associated with worse outcomes in the intensive care unit (ICU). However, in Korea the prevalence of deep sedation and its impact on patients in the ICU are not well known. Methods: From April 2020 to July 2021, a multicenter, prospective, longitudinal, noninterventional cohort study was performed in 20 Korean ICUs. Sedation depth extent was divided into light and deep using a mean Richmond Agitation–Sedation Scale value within the first 48 hours. Propensity score matching was used to balance covariables; the outcomes were compared between the two groups. Results: Overall, 631 patients (418 [66.2%] and 213 [33.8%] in the deep and light sedation groups, respectively) were included. Mortality rates were 14.1% and 8.4% in the deep and light sedation groups (P = 0.039), respectively. Kaplan-Meier estimates showed that time to extubation (P < 0.001), ICU length of stay (P = 0.005), and death (P = 0.041) differed between the groups. After adjusting for confounders, early deep sedation was only associated with delayed time to extubation (hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.55–0.80; P < 0.001). In the matched cohort, deep sedation remained significantly associated with delayed time to extubation (HR, 0.68; 95% CI, 0.56–0.83; P < 0.001) but was not associated with ICU length of stay (HR, 0.94; 95% CI, 0.79–1.13; P = 0.500) and in-hospital mortality (HR, 1.19; 95% CI, 0.65–2.17; P = 0.582). Conclusion: In many Korean ICUs, early deep sedation was highly prevalent in mechanically ventilated patients and was associated with delayed extubation, but not prolonged ICU stay or in-hospital death.ope

Metallic Component Preserving Algorithm Based on the Cerebral Computed Tomography Angiography in Aneurysm Surgery

The purpose of this study was to investigate the viability of the proposed method in preventing the loss of metallic components including the clip and coil in cerebral computed tomography angiography (CTA). Forty patients undergoing surgery for aneurysms carried metallic materials. The proposed method is based on conventional bone subtraction CTA (BS-CTA) system. Briefly, the position of metal components was determined using the threshold value and a region of interest (ROI). An appropriate threshold was used to separate the background from the target materials based on the Otsu method. A three-dimensional (3D) rendering was performed from the proposed BS-CTA data carrying the extracted target information. The accuracy of clip and coil region measured using the dice similarity coefficient (DSC) and bidirectional Hausdorff distance (HD) is reported. The metallic components of the proposed BS-CTA were significantly visualized in various patient cases. Quantitative evaluation using the proposed method is based on the mean DSC of 0.93 with a standard deviation (SD) of ±0.05 (e.g., maximum value = 0.99, minimum value = 0.75, 95% confidence interval (CI) = 0.91 to 0.95, and all p < 0.05). The mean HD was 1.50 voxels with an SD of ± 0.58 (e.g., maximum value = 5.95, minimum value = 0.12, 95% CI = 1.10 to 1.90, and all p < 0.05). The proposed method demonstrates effective segmentation of the metallic component and application to the existing conventional BS-CTA system.ope

Clinical Associations between Serial Electrocardiography Measurements and Sudden Cardiac Death in Patients with End-Stage Renal Disease Undergoing Hemodialysis

The rate of sudden cardiac death (SCD) for hemodialysis (HD) patients is significantly higher than that observed in the general population and have the highest risk for arrhythmogenic death. In this multi-center study, patients starting hemodialysis in each hospital were enrolled; they underwent regular check-ups in an open-patient clinic. We examined serial electrocardiography (ECG) data in patients undergoing HD and determined their associations with the occurrence of SCD. Of 678 enrolled subjects who underwent serial ECG before and after hemodialysis, 291 died and 39 developed SCD. In all subjects, the QT peak-to-end (QTpe) interval at all leads and QRS duration were shortened after hemodialysis. The SCD group showed a significant change in the QTpe interval of the inferior, anterior, and lateral leads before and after hemodialysis compared with the survivor group (p < 0.001). In the pre-hemodialysis ECG, SCD patients had significantly longer QTpe intervals in all leads (p < 0.001) and a longer QRS duration (92.6 ± 14.0 vs. 100.6 ± 14.9 ms, p = 0.015) than survivors. In conclusion, patients with a longer QTpe interval before hemodialysis and large changes in ECG parameters after hemodialysis might be at a higher risk of SCD. Therefore, changes in the ECG before and after hemodialysis could help to predict SCD.ope

Impact of Intensivist and Nursing Staff on Critically Ill Patient Mortality: A Retrospective Analysis of the Korean NHIS Cohort Data, 2011-2015

Purpose: Critical care medicine continues to evolve. However, critical care cases require increasing amount of medical resources. Intensive care unit (ICU) mortality significantly impacts the overall efficiency of healthcare resources within a system of limited medical resources. This study investigated the factors related to ICU mortality using long-term nationwide cohort data in South Korea. Materials and methods: This retrospective cohort study used data of 14905721 patients who submitted reimbursement claims to the Korean Health Insurance Service between January 1, 2011 and December 31, 2015. A total of 1498102 patients who were admitted to all ICU types, except neonatal and long-term acute care hospitals, were enrolled. Results: Of the total 1498102 participants, 861397 (57.5%) were male and 636705 (42.5%) were female. The mean age at admission was 63.4±18.2 years; most of the subjects were aged over 60 years. During the 5-year period, in-hospital mortality rate was 12.9%. In Cox analysis, both in-hospital and 28-day mortality rates were significantly higher in male patients and those of lower socioeconomic status. As age increased and the number of nursing staff decreased, the mortality risk increased significantly by two or three times. The mortality risk was lower in patients admitted to an ICU of a tertiary university hospital and an ICU where intensivists worked. Conclusion: The number of nursing staff and the presence of an intensivist in ICU were associated with the ICU mortality rate. Also, increasing the number of nursing staff and the presence of intensivist might reduce the mortality rate among ICU patients.ope