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Background: Since the era of “thyroid cancer epidemic,” many Korean academic societies discouraged the use of ultrasonography in healthy individuals and revised the Korean Thyroid Imaging Reporting and Data System to address the overscreening and overdiagnosis issues. This study aimed to evaluate the change in the diagnostic effectiveness of thyroid cancer screening over the last decade.Methods: This single-center, retrospective observational study analyzed the data of 125,962 thyroid nodules obtained during cancer screening at the health promotion center of Seoul National University Bundang Hospital from 2010 to 2019. Only 327 thyroid cancer cases pathologically confirmed by fine-needle aspiration (FNA) were included in the study. The strength of the association between the number of FNA and (1) the number of thyroid cancer diagnoses, (2) the positive predictive values (PPVs), and (3) the difference in PPV from the previous year were evaluated using Pearson’s correlation analysis.Results: The number of thyroid FNA biopsies as well as the thyroid cancer diagnoses decreased from 2010 to 2019 (166 to 48 [-71.1%] vs. 43 to 22 [-48.8%]). The PPV of FNA biopsies increased from 25.9% to 45.8% (+76.8%) and was negatively correlated with the number of FNA biopsies performed (R=-0.87, P

Age-related vision loss (ARVL) has been shown to interfere with older adults’ occupational engagement. The primary purpose was to examine the role social networks play in facilitating/constraining engagement in desired occupations for older adults with ARVL. This study adopted a constructivist narrative methodology. Five older adults, ≥ 60 years of age with ARVL, participated in three virtual interviews, which were coded using thematic analysis. Three overarching themes were identified: (a) Diverse Social Networks Fulfill Different Occupational and Psychosocial Needs, (b) Retaining a Sense of Independence through Seeking Reciprocity in Social Relationships, and (c) Community Mobility and Technology Support as Essential for Preserving Social Relationships. Findings broaden understandings of how informal/formal social networks are involved in shaping visually-impaired older adults’ adaptation to ARVL and related occupational changes. Findings may help improve the quality and delivery of low-vision rehabilitation services to optimize their contribution to occupational engagement.

During the recent several decades, lateral flow immunoassay (LFIA) constructed with gold nanoparticle (AuNP) has been widely utilized to conveniently detect target analyte. However, AuNP-based LFIA has limitations, such as limited detection sensitivity and quantification capability. Herein, to overcome these constraints, we have developed cerium oxide nanoparticle (nanoceria)-based LFIA for C-reactive protein (CRP) detection in human serum samples. It was fabricated with nanoceria, a notable nanozyme that shows an oxidase activity to quickly oxidize organic substrate, such as 3,3',5,5'-tetramethylbenzidine (TMB), to produce colored product without any oxidizing agent (e.g., hydrogen peroxide), which is advantageous for realizing point-of-care testing (POCT) applications. By employing human blood serum spiked with CRP, the nanoceria-based LFIA showed two blue-colored lines on the test and control region within 3 min via TMB oxidation, by the captured nanoceria through antigen-antibody interaction. The produced blue-colored lines were distinguished by naked eyes and quantitated with real images acquired by a conventional smartphone with the ImageJ software. With this strategy, target CRP was specifically determined down to 117 ng mL

This study aimed to assess the effects of remote ischemic preconditioning (RIPC) on liver function in donors and recipients after living donor liver transplantation (LDLT).Ischemia reperfusion injury (IRI) is known to be associated with graft dysfunction after liver transplantation. RIPC is used to lessen the harmful effects of IRI.A total of 148 donors were randomly assigned to RIPC (n = 75) and control (n = 73) groups. RIPC involves 3 cycles of 5-minute inflation of a blood pressure cuff to 200 mm Hg to the upper arm, followed by 5-minute reperfusion with cuff deflation. The primary aim was to assess postoperative liver function in donors and recipients and the incidence of early allograft dysfunction and graft failure in recipients.RIPC was not associated with any differences in postoperative aspartate aminotransferase (AST) and alanine aminotransferase levels after living donor hepatectomy, and it did not decrease the incidence of delayed graft hepatic function (6.7% vs 0.0%, P = 0.074) in donors. AST level on postoperative day 1 [217.0 (158.0, 288.0) vs 259.5 (182.0, 340.0), P = 0.033] and maximal AST level within 7 postoperative days [244.0 (167.0, 334.0) vs 296.0 (206.0, 395.5), P = 0.029) were significantly lower in recipients who received a preconditioned graft. No differences were found in the incidence of early allograft dysfunction (4.1% vs 5.6%, P = 0.955) or graft failure (1.4% vs 5.6%, P = 0.346) among recipients.RIPC did not improve liver function in living donor hepatectomy. However, RIPC performed in liver donors may be beneficial for postoperative liver function in recipients after living donor liver transplantation.

Some research suggests social isolation and loneliness are important risk factors for reduced successful aging and cognitive health. However, findings are inconsistent and no prior systematic review has investigated whether social isolation and loneliness are associated with the memory domain of cognition. This review examined whether social isolation and loneliness individually and jointly affected the memory of middle- and older-aged adults.We used PubMed, PsycInfo, and Scopus to search for comparative studies that examined the impact of both loneliness and social isolation (e.g., social activity, social networks) on memory (including all subtypes) in populations aged ≥ 45 years. Three raters performed data extraction and risk of bias assessment using the Joanna Briggs Institute checklist. Data were synthesized narratively following the Synthesis without Meta-Analysis guideline.In 12 included articles, higher levels of loneliness and social isolation (combining a range of different indicators) were associated with lower memory performance, where the interaction between loneliness and social isolation had the largest adverse effect on memory, followed by social isolation alone, and followed by loneliness alone. However, substantial heterogeneity was observed in the composition of the two most common indicators of social isolation (social network size, social activity participation), with the magnitude of most results being clinically non-important. Most articles had moderate risk of bias.This review found an inverse association between social isolation/loneliness and memory, and outlines future steps to systematically combine the two constructs and measure social isolation in a consistent, multi-modal format.

We propose a new learning and inferring model that generates digital holograms using deep neural networks (DNNs). This DNN uses a generative adversarial network, trained to infer a complex two-dimensional fringe pattern from a single object point. The intensity and fringe patterns inferred for each object point were multiplied, and all the fringe patterns were accumulated to generate a perfect hologram. This method can achieve generality by recording holograms for two spaces (16 Space and 32 Space). The reconstruction results of both spaces proved to be almost the same as numerical computer-generated holograms by showing the performance at 44.56 and 35.11 dB, respectively. Through displaying the generated hologram in the optical equipment, we proved that the holograms generated by the proposed DNN can be optically reconstructed.

The purpose of this study is to help teachers of AR-based education by reviewing the literature on the types, learning effects and limitations of AR technology used in Korean AR-based education. Therefore, this thesis examines the literature focusing on thesis and articles of Korean thesis, and defines the definition of AR, technical elements, implementation method, utilization media, usage and trends, educational status, and educational effects and limitations. As a result, the classes using AR-based education could be easily immersed by learners and the presence of learning occurred. In addition, it is possible to take advantage of the AR, enabling immediate training using GPS and collaborative training using the network. AR-based education is becoming increasingly popular according to the use of digital textbooks through AR technology and AR education contents using mobile devices. However, there are limitations to AR implementation media such as qualitative differences in AR educational contents, high price, motion sickness and dizziness of HMD devices. Therefore, in order to achieve AR-based education in educational institutions and educational sites, this paper presents the development of AR implementation media suitable for the level of learners, provides flexible AR curriculum guidelines, industry-academic cooperation between companies for technology development, and inspection / censorship of educational contents. It suggests that a procedure should be provided.

Background: Percutaneous atrial septal defect (ASD) device closure is usually performed under general anesthesia (GA) because it can ensure protection of the airway from the effects of insertion of the transesophageal echocardiogram probe insertion. However, recent studies have suggested that this procedure can be performed safely under deep sedation also. Thus, we compared the efficacy of using monitored anesthesia care (MAC) with deep sedation versus GA to perform this procedure and the post-procedural outcomes and incidence of complications associated with these two methods of anesthesia. Methods: We retrospectively analyzed cases involving 311 patients who underwent ASD device closures from January 2011 to December 2015. The demographics, laboratory values, echocardiographic findings, and intraoperative data of these patients were assessed. GA was induced with a continuous infusion of propofol and remifentanil using a target control infusion pump. MAC with deep sedation was performed by using a continuous infusion of dexmedetomidine and remifentanil. The primary outcome of the study was the overall complication rate that included the incidence of aspiration pneumonia, sore throat, dysphagia, vocal cord palsy, neurologic complication, device-related complications, and other minor complications during the procedure; and the secondary outcomes were the turnover time, procedure time, and duration of hospital stay. Results: No significant differences were observed in the complication rate and length of the hospital stay between the MAC group and the GA group. However, the turnover time was significantly longer in the GA group than in the MAC group (56.2±13.3 vs . 51.0±15.4 min, P=0.004). Conclusions: MAC under deep sedation is an effective and safe anesthetic option comparable to GA for performing percutaneous ASD device closures.

In this paper, we propose a new method for coding a full complex hologram with random phase. Since holograms with random phase have very unique spatial and frequency characteristics, a new compression method suitable for such holograms is required. We analyze the frequency characteristics of holograms with random phases and propose a new adaptive discrete wavelet transform (aDWT). Next, we propose a new modified zerotree alogrithm (mZTA) suitable for the subband configuration generated by the modified wavelet transform method. The results of the compression using the proposed method showed higher efficiency than the previous method, and the reconstructed images showed visually superior results.

In this paper, we propose a new method for generating volumetric holograms using point cloud and mesh. Traditional digital holograms only record information about specific viewpoints. In this paper, we propose a method to store real objects in the form of omnidirectional 3D point cloud and mesh, and to generate holograms of various views of the stored point cloud. In order to record a better-quality hologram, a method of weighting the brightness of a light source according to the direction of light is proposed.

Ha, H.K.; Seo, J.Y.; Jung, Y.H.; Ha. H.J.; Kim, S.B.; Kang, J.W.; Kim, Y.H., and Ryu, J., 2018. Dynamics of sediment resuspension in the inner harbor under different forcing conditions: A case study of Ulsan, Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 451–455. Coconut Creek (Florida), ISSN 0749-0208.Bottom mooring data of currents and backscatter strength derived from a 1200-kHz acoustic Doppler current profiler were collected in the inner Onsan Harbor, Ulsan during the summer season (July 5 to August 5, 2016). The mean volume backscattering strength (MVBS), which is a proxy of suspended sediment concentration (SSC), continued to exhibit distinct signatures of sediment erosion (or resuspension) under different forcing conditions such as tides, winds, and precipitation. Results exhibit the different patterns of sediment resuspension between spring and neap tides. During spring tide, the extensive tidal forcing provided a favorable condition to resuspend sediments trapped near the bed. The MVBS with high SSC was consistently recorded. During neap tide, on the other hand, the MVBS with high SSC was intermittently recorded, which was related to the strong wind events. While the flow was being intensified by winds, the short-lasting (2–4 hours) sharp spikes of MVBS were observed. The stratification developed by increased precipitation might cause to block the upward transport of sediments near the bed, even though the strong winds (>13.6 m s−1) lasted over 4 days. These outcomes could give insight into the complexity of hydrodynamics and sediment transport occurring in the harbor where various natural and artificial forcings are combined.

High-throughput plant phenotyping has revealed its importance by illuminating complex questions about plant growth, development, and response to the environment. Recently emerging technologies including un-maned vehicle as an image acquiring technology and machine learning as image analyzing technology have enabled the use of high-throughput phenotyping of plants for basic and applied sciences. Digital image analysis is one of methods for high throughput phenotyping. However, those techniques are not accessible because of high costs in general and the lack of man power to efficiently operate them. Here, we propose an easily accessible high-throughput phenotyping tool for biomass for many researchers. Four sorghum cultivars were evaluated for their height, a variable well documented for its high correlation with biomass, with both hand-collection and image taking in order to determine if image analysis for biomass in sorghum could replace hand data collection of plant height. Vertical plant images were obtained using a digital camera at one-week interval for 5 weeks. Plant height and node height were hand-collected at the same time. Images were analyzed using a tool, called Canopeo ( http://www.canopeoapp.com ). Biomass was measured indirectly as percentage units by counting the green pixels in each image. Strong and significant correlations between the percentage of green color and plant height and between the percentage of green color and node height were found for each cultivar and measurement. The results of this proof-of-concept study strongly indicate that digital image analysis could replace the intense labor needed to collect data related to biomass.

Background Only few studies have assessed variability in the results obtained by the readers with different experience levels in comparison with automated volumetric breast density measurements. Purpose To examine the variations in breast density assessment according to BI-RADS categories among readers with different experience levels and to compare it with the results of automated quantitative measurements. Material and Methods Density assignment was done for 1000 screening mammograms by six readers with three different experience levels (breast-imaging experts, general radiologists, and students). Agreement level between the results obtained by the readers and the Volpara automated volumetric breast density measurements was assessed. The agreement analysis using two categories—non-dense and dense breast tissue—was also performed. Results Intra-reader agreement for experts, general radiologists, and students were almost perfect or substantial (k = 0.74–0.95). The agreement between visual assessments of the breast-imaging experts and volumetric assessments by Volpara was substantial (k = 0.77). The agreement was moderate between the experts and general radiologists (k = 0.67) and slight between the students and Volpara (k = 0.01). The agreement for the two category groups (nondense and dense) was almost perfect between the experts and Volpara (k = 0.83). The agreement was substantial between the experts and general radiologists (k = 0.78). Conclusion We observed similar high agreement levels between visual assessments of breast density performed by radiologists and the volumetric assessments. However, agreement levels were substantially lower for the untrained readers.

To assess the diagnostic performance of unenhanced abbreviated protocol (AP) comprising fused diffusion-weighted imaging (DWI) using T1-weighted imaging (T1WI) with DWI maximum-intensity projections (DWI MIPs) for screening patients with a personal history of breast cancer (PHBC). This institutional review board-approved retrospective observational study included 343 patients with PHBC who underwent 3T breast magnetic resonance imaging (MRI) between November 2013 and September 2015. Three breast radiologists reviewed the DWI MIPs of the AP to identify lesions, and the remaining axial AP images to characterize the detected lesions and establish the breast imaging reporting and data system final assessment. The conventional protocol (CP) images were also evaluated in the same way. The decision-making times were recorded. MRI acquisition time was approximately 5 min for AP. The mean times to read MIPs and remaining images were shorter in AP than in CP (5.5 and 22.1 s vs. 7.8 and 29.6 s). On DWI MIPs, the readers detected 9, 8, and 9 of 9 pathologically proven cancers, with negative predictive values (NPVs) of 100.0, 99.6, and 100.0%. Complete AP showed sensitivities of 88.9, 100.0, and 88.9% and specificities of 94.8, 93.4, and 95.1%. Complete CP showed sensitivities of 100.0, 100.0, and 88.9% and specificities of 93.4, 94.0, and 96.3%. An unenhanced AP had a short acquisition time of 5 min, and DWI MIPs showed NPVs greater than 99% across readers. The diagnostic performance of complete AP was equivalent to that of CP for screening patients with PHBC.

This study set out to investigate the effects of multiple roles on depressive symptoms in women. The role of women was divided into worker, household worker, spouse, parent, and caregiver roles to identify the differences in depressive symptoms according to the number of roles, role-fulfillment, and role-combination. Using the sixth raw data of the 2016 Korean Longitudinal Survey of Women and Families for analysis, the data had 6198 respondents who did not have missing values in the major variables. There are three main findings of this study: (1) as the number of roles increased, depressive symptoms of women was decreased. In addition, role-combination was a more meaningful element, (2) women who did not have any roles tended to be more depressed, (3) the caregiver role showed a negative effect on depressive symptoms of women. This study was to include the various aspects of women&rsquo, s roles and to determine the effects of multi-roles on depressive symptoms in women.

Optical alignment of the mirror components in a space telescope is an important process for obtaining high optical resolution and performance of the camera system. The alignment of mirrors depends on the external coordinate frame using a cube mirror, and a relative coordinate mapping between the mirror and the cube mirror before optical system integration is a prerequisite step. Therefore, in order to align the spacecraft camera mirrors, the relative coordinates of the vertex of each mirror and the corresponding cube mirror must be accurately measured. This paper proposes a new method for finding the vertex position of a primary mirror by using an optical fiber and alignment segments of the computer-generated hologram (CGH). The measurement system is composed of an optical testing interferometer, a multimode optical fiber. We used 2 theodolites to measure the relative coordinates of the optical fiber located at the mirror vertex with respect to the cube mirror, and achieved a measurement precision of less than 25um.

In this paper, we propose a new method to generate interference patterns by using deep learning based on GAN. And we suggest how to obtain the interference pattern of cosine and sine in a hologram modelling equation corresponding to the point source by training them into different GAN model.

This paper deals with Modulation Index (MI) of Voltage Source Converter (VSC) HVDC System based on Modular Multilevel Converter (MMC). In the 2-level converter, the purpose of the MI is to maximize the AC voltage reference at the fixed DC voltage. Unlike 2-level converter, MMC topology is to make the converter a voltage source using capacitor. And the AC voltage reference is distorted by the circulating current, so this circulating current affects the MI. Also, the AC Network conditions such as AC voltage variation, reactive power etc., also affect the MI. It is necessary to optimize modulation index according to internal and external conditions. This paper deals with the optimization method for MI of MMC HVDC System.