Publications by authors named "Donghyun Kim"

259 Publications

Analysis of mouse male germ cell-specific or -predominant Tex13 family genes encoding proteins with transcriptional repressor activity.

Mol Biol Rep 2021 Apr 3. Epub 2021 Apr 3.

School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea.

Mammalian spermatogenesis is a highly organized process with successive mitotic, meiotic, and postmeiotic phases. This unique developmental process is characterized by the involvement of spermatogenic cell-specific genes. In this study, we identified and investigated testis expressed gene 13 (Tex13) family genes, consisting of Tex13a, Tex13b, Tex13c1, and Tex13d, in mice. All of these genes were transcribed specifically or predominantly in male germ cells, and their transcription was developmentally regulated. Proteins encoded by the Tex13 genes were predicted to have a conserved domain of ~ 145 amino acids. Tex13a, Tex13c1, and Tex13d encode additional C-terminal regions containing a short conserved sequence termed a zinc finger-RAN binding protein 2 (zf-RanBP2) or zf-RanBP2-like domain. As TEX13B reportedly has transcriptional repressor activity, we examined the effect of the TEX13 proteins on transcriptional regulation using a reporter assay. All of the TEX13 proteins exhibited transcriptional repressor activity. This activity was revealed to reside in the TEX13B-corresponding regions of TEX13A, TEX13C1, and TEX13D. Further, we found that the C-terminal regions of TEX13A, TEX13C1, and TEX13D also have inhibitory activities. These results suggest that male germ cell-specific or -predominant TEX13 proteins commonly function in transcriptional repression as transcription cofactors and/or RNA binding proteins.
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http://dx.doi.org/10.1007/s11033-021-06265-5DOI Listing
April 2021

Association of Dietary Total Antioxidant Capacity with Bone Mass and Osteoporosis Risk in Korean Women: Analysis of the Korea National Health and Nutrition Examination Survey 2008-2011.

Nutrients 2021 Mar 31;13(4). Epub 2021 Mar 31.

Department of Food and Nutrition, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Korea.

Antioxidant intake has been suggested to be associated with a reduced osteoporosis risk, but the effect of dietary total antioxidant capacity (TAC) on bone health and the risk of osteoporosis remains unclear. We aimed to assess the hypothesis that dietary TAC is positively associated with bone mass and negatively related to the risk of osteoporosis in Korean women. This cross-sectional study was performed using data from the Korea National Health and Nutrition Examination Survey. Dietary TAC was estimated using task automation and an algorithm with 24-h recall data. In total, 8230 pre- and postmenopausal women were divided into four groups according to quartiles of dietary TAC. Dietary TAC was negatively associated with the risk of osteoporosis (odds ratio, 0.73; 95% confidence interval, 0.54-0.99; -value = 0.045) in postmenopausal women, but not in premenopausal women. Dietary TAC was positively associated with bone mineral content (BMC) and bone mineral density of the femoral neck and lumbar spine in postmenopausal women and BMC of the total femur and lumbar spine in premenopausal women. Our study suggests that dietary TAC is inversely associated with the risk of osteoporosis in postmenopausal women and positively associated with bone mass in both pre- and postmenopausal women.
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http://dx.doi.org/10.3390/nu13041149DOI Listing
March 2021

A Commonly Used Biocide 2-N-octyl-4-isothiazolin-3-oneInduces Blood-Brain Barrier Dysfunction via Cellular Thiol Modification and Mitochondrial Damage.

Int J Mol Sci 2021 Mar 4;22(5). Epub 2021 Mar 4.

College of Pharmacy Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan 15588, Korea.

Isothiazolinone (IT) biocides are potent antibacterial substances commonly used as preservatives or disinfectants, and 2-n-Octyl-4-isothiazolin-3-one (OIT; octhilinone) is a common IT biocide that is present in leather products, glue, paints, and cleaning products. Although humans are exposed to OIT through personal and industrial use, the potentially deleterious effects of OIT on human health are still unknown. To investigate the effects of OIT on the vascular system, which is continuously exposed to xenobiotics through systemic circulation, we treated brain endothelial cells with OIT. OIT treatment significantly activated caspase-3-mediated apoptosis and reduced the bioenergetic function of mitochondria in a bEnd.3 cell-based in vitro blood-brain barrier (BBB) model. Interestingly, OIT significantly altered the thiol redox status, as evidenced by reduced glutathione levels and protein S-nitrosylation. The endothelial barrier function of bEnd.3 cells was significantly impaired by OIT treatment. OIT affected mitochondrial dynamics through mitophagy and altered mitochondrial morphology in bEnd.3 cells. N-acetyl cysteine significantly reversed the effects of OIT on the metabolic capacity and endothelial function of bEnd.3 cells. Taken together, we demonstrated that the alteration of the thiol redox status and mitochondrial damage contributed to OIT-induced BBB dysfunction, and we hope that our findings will improve our understanding of the potential hazardous health effects of IT biocides.
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http://dx.doi.org/10.3390/ijms22052563DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7975974PMC
March 2021

Quality of Recovery after Laparoscopic Cholecystectomy Following Neuromuscular Blockade Reversal with Neostigmine or Sugammadex: A Prospective, Randomized, Controlled Trial.

J Clin Med 2021 Mar 1;10(5). Epub 2021 Mar 1.

Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Gumi-ro, Bundang-gu, Seongnam-si 13620, Korea.

The risk of neuromuscular blockade is certainly minimized by sugammadex in combination with monitoring. However, the effect of sugammadex-aided recovery on patients' satisfaction is unclear. This study compared the Quality of Recovery (QoR)-15 score, which is a patient-reported outcome, in patients undergoing laparoscopic cholecystectomy. Eighty patients were randomly assigned to the neostigmine or sugammadex groups. At the end of surgery, neostigmine or sugammadex was administered, and tracheal extubation was performed after confirmation of a train of four ratio ≥ 0.9. The QoR-15 questionnaire was administered at 1 day before surgery and on post-operative days (POD) 1 and 2. The primary outcome was the QoR-15 score on POD 1. The secondary outcomes were the QoR-15 score on POD 2, modified Aldrete score, length of post-anesthetic care unit stay, post-operative pain, administration of anti-emetics, urinary retention, and length of hospital stay. No significant differences were found in QoR-15 scores on POD 1 (94.4 vs. 95.5, = 0.87) or 2 (116.3 vs. 122, = 0.33). Secondary outcomes were also comparable, with the exception of urinary retention (15.8% neostigmine vs. 2.6% sugammadex, = 0.04). This study demonstrated that the quality of recovery was comparable between the neostigmine and sugammadex groups when reversal and tracheal extubation were performed in accordance with the current guidelines.
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http://dx.doi.org/10.3390/jcm10050938DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7957716PMC
March 2021

rt269I Type of Hepatitis B Virus (HBV) Polymerase versus rt269L Is More Prone to Mutations within HBV Genome in Chronic Patients Infected with Genotype C2: Evidence from Analysis of Full HBV Genotype C2 Genome.

Microorganisms 2021 Mar 15;9(3). Epub 2021 Mar 15.

Department of Biomedical Sciences, Microbiology and Immunology, and Liver Institute, College of Medicine, Seoul National University, Seoul 03080, Korea.

Recently, it has been reported that the rt269I type of hepatitis B virus (HBV) polymerase (Pol) versus the rt269L type is more significantly related to lower viral replication and HBeAg negative infections in chronic hepatitis B (CHB) patients of genotype C2. In this study, we compared mutation rates within HBV genomes between rt269L and rt269I using a total of 234 HBV genotype C2 full genome sequences randomly selected from the HBV database (115 of rt269L and 119 of rt269I type). When we applied the Benjamini and Hochberg procedure for multiple comparisons, two parameters, dN and d, at the amino acids level in the Pol region were significantly higher in the rt269I type than in the rt269L type. Although it could not reach statistical significance from the Benjamini and Hochberg procedure, nonsynonymous (NS) mutations in the major hydrophilic region (MHR) or "a" determinant in the surface antigens (HBsAg ORF) related to host immune escape or vaccine escape are more frequently generated in rt269I strains than in rt269L. We also found that there are a total of 19 signature single nucleotide polymorphisms (SNPs), of which 2 and 17 nonsynonymous mutation types were specific to rt269L and rt269I, respectively: Of these, most are HBeAg negative infections (preC-W28*, X-V5M and V131I), lowered HBV DNA or virion production (C-I97F/L, rtM204I/V) or preexisting nucleot(s)ide analog resistance (NAr) (rtN139K/H, rtM204I/V and rtI224V) or disease severity (preC-W28*, C-I97F/L, C-Q182K/*, preS2-F141L, S-L213I/S, V/L5M, T36P/S/A, V131I, rtN139K/H, rtM204I/V and rtI224V). In conclusion, our data showed that rt269I types versus rt269L types are more prone to overall genome mutations, particularly in the Pol region and in the MHR or "a" determinant in genotype C2 infections and are more prevalent in signature NS mutations related to lowered HBV DNA replication, HBsAg and HBeAg secretion and potential NAr variants and hepatocellular carcinoma (HCC), possibly via type I interferon (IFN-I)-mediated enhanced inflammation. Our data suggest that rt269L types could contribute to liver disease progression via the generation of immune escape or enhanced persistent infection in chronic patients of genotype C2.
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http://dx.doi.org/10.3390/microorganisms9030601DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7999911PMC
March 2021

Atomic-Layer-Deposition-Based 2D Transition Metal Chalcogenides: Synthesis, Modulation, and Applications.

Adv Mater 2021 Mar 21:e2005907. Epub 2021 Mar 21.

School of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722, Republic of Korea.

Transition metal chalcogenides (TMCs) are a large family of 2D materials with different properties, and are promising candidates for a wide range of applications such as nanoelectronics, sensors, energy conversion, and energy storage. In the research of new materials, the development and investigation of industry-compatible synthesis techniques is of key importance. In this respect, it is important to study 2D TMC materials synthesized by the atomic layer deposition (ALD) technique, which is widely applied in industries. In addition to the synthesis of 2D TMCs, ALD is used to modulate the characteristic of 2D TMCs such as their carrier density and morphology. So far, the improvement of thin film uniformity without oxidation and the synthesis of low-dimensional nanomaterials on 2D TMCs have been the research focus. Herein, the synthesis and modulation of 2D TMCs by ALD is described, and the characteristics of ALD-based TMCs used in nanoelectronics, sensors, and energy applications are discussed.
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http://dx.doi.org/10.1002/adma.202005907DOI Listing
March 2021

MXene-Graphene Field-Effect Transistor Sensing of Influenza Virus and SARS-CoV-2.

ACS Omega 2021 Mar 2;6(10):6643-6653. Epub 2021 Mar 2.

Department of Civil, Architectural, and Environmental Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States.

An MXene-graphene field-effect transistor (FET) sensor for both influenza virus and 2019-nCoV sensing was developed and characterized. The developed sensor combines the high chemical sensitivity of MXene and the continuity of large-area high-quality graphene to form an ultra-sensitive virus-sensing transduction material (VSTM). Through polymer linking, we are able to utilize antibody-antigen binding to achieve electrochemical signal transduction when viruses are deposited onto the VSTM surface. The MXene-graphene VSTM was integrated into a microfluidic channel that can directly receive viruses in solution. The developed sensor was tested with various concentrations of antigens from two viruses: inactivated influenza A (H1N1) HA virus ranging from 125 to 250,000 copies/mL and a recombinant 2019-nCoV spike protein ranging from 1 fg/mL to 10 pg/mL. The average response time was about ∼50 ms, which is significantly faster than the existing real-time reverse transcription-polymerase chain reaction method (>3 h). The low limit of detection (125 copies/mL for the influenza virus and 1 fg/mL for the recombinant 2019-nCoV spike protein) has demonstrated the sensitivity of the MXene-graphene VSTM on the FET platform to virus sensing. Especially, the high signal-to-viral load ratio (∼10% change in source-drain current and gate voltage) also demonstrates the ultra-sensitivity of the developed MXene-graphene FET sensor. In addition, the specificity of the sensor was also demonstrated by depositing the inactivated influenza A (H1N1) HA virus and the recombinant 2019-nCoV spike protein onto microfluidic channels with opposite antibodies, producing signal differences that are about 10 times lower. Thus, we have successfully fabricated a relatively low-cost, ultrasensitive, fast-responding, and specific inactivated influenza A (H1N1) and 2019-nCoV sensor with the MXene-graphene VSTM.
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http://dx.doi.org/10.1021/acsomega.0c05421DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7944395PMC
March 2021

Shock Resistive Flexure-Based Anthropomorphic Hand with Enhanced Payload.

Soft Robot 2021 Mar 5. Epub 2021 Mar 5.

Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea.

In this study, a Crossed Flexural Hinge (CFH) structure was used for the design of a humanoid robot hand that can absorb any abrupt external force and that has a large payload, giving it the advantages of both rigid and compliant robots. Structural problems were identified through a 6 × 6 stiffness matrix to analyze whether CFH is suitable for use as an anthropomorphic robot hand. To reinforce the weak stiffness, a paired CFH (p-CFH) structure was proposed for the robot hand joints. In addition, it was verified through theoretical and experimental methods that p-CFH has superior stiffness characteristics compared to conventional CFH. When designing the anthropomorphic robot hand, p-CFH was appropriately deformed and applied. Using an underactuated wire mechanism suitable for the structure of the robot hand, it was possible to grasp objects of various shapes in a shape-adaptive manner. It was confirmed that the final anthropomorphic robot hand was able to stably hold an object of an unspecified shape without precisely controlling the motor. And the robot hand can also hold a heavy object due to the increased rigidity of the p-CFH. In addition, by conducting the qualitative impact test in which the robot was subjected to an impact in an arbitrary direction, it was confirmed that the robot, due to compliance of the joints, can absorb impact without incurring damage. Finally, a quantitative impact test was conducted in all directions, and the shock absorbing capability of anthropomorphic robot hand was verified through numerical comparison with the control model.
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http://dx.doi.org/10.1089/soro.2020.0067DOI Listing
March 2021

Skin tactile surface restoration using deep learning from a mobile image: An application for virtual skincare.

Skin Res Technol 2021 Mar 2. Epub 2021 Mar 2.

Haptic Engineering Research Laboratory, Department of Information and Telecommunication Engineering, Incheon National University, Incheon, Republic of Korea.

Background: For virtual skincare using a touch feedback interface, reconstructing a 3D skin tactile surface from a mobile skin image is imperative for a dermatologist to palpate the skin surface that presents tactile characteristics of the subcutaneous tissues. However, the precise tactile reconstruction from a single view image is a challenging research problem due to varying illumination conditions.

Methods: In this study, a deep learning-based tactile reconstruction scheme is proposed to restore tactile properties from light distortion and reconstruct the 3D tactile surface from a mobile skin image. Our method consists of light distortion removal using deep learning, cGAN, and 3D tactile surface generation based on image gradients.

Results: The proposed method was tested by conducting two evaluation experiments in terms of removing light distortion and reconstructing 3D skin tactile surface in comparison with other well-known methods. The results demonstrated that our method outperforms existing other methods in both illumination-free image restoration and 3D surface reconstruction.

Conclusion: The proposed method is a promising approach in that tactile property distorted by illuminations can be completely restored using deep learning with a smaller training set and the precise reconstruction of 3D skin tactile surface can be achieved to be ready for a remotely touchable interface for virtual skincare applications.
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http://dx.doi.org/10.1111/srt.13009DOI Listing
March 2021

Exploratory study on the spatial relationship between emerging infectious diseases and urban characteristics: Cases from Korea.

Authors:
Donghyun Kim

Sustain Cities Soc 2021 Mar 28;66:102672. Epub 2020 Dec 28.

Department of Urban Planning and Engineering, Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-Gu, Busan, 46241, Republic of Korea.

In the modern global context of interconnected populations, the recent emergence of infectious diseases involves complex interactions. The purpose of this study is to investigate the spatial correlations between urban characteristics, taking into account the socio-ecological aspects, and the emergence of infectious diseases. Using exploratory spatial data analysis and spatial regression between the infectious disease emergence data and 14 urban characteristics, we analyzed 225 spatial units in South Korea, where there was a re-emergence of measles and a 2015 outbreak of Middle East Respiratory Syndrome. As results of exploratory spatial data analysis, the emerging infectious diseases had spatial dependence and showed spatial clusters. Spatial regression models showed that urban characteristic factors had different effects according to the type of infectious disease. Common factors were characteristics related to low socioeconomic status in water or food-borne diseases and manageable infectious diseases. Intermittent infections disease epidemics are related to high-quality residential environments and the response capacity of the local government. New infectious diseases are different than other infectious diseases, which are related to the ecological environment. This study suggests spatial policies for preventing infectious diseases considering the spatial relationships between urban characteristics and infectious diseases as well as the management of public health.
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http://dx.doi.org/10.1016/j.scs.2020.102672DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7828747PMC
March 2021

Anti-Obesity Effects of Extract in Zucker Fatty Rats and High-Fat Diet Sprague Dawley Rats through Upregulation of Uncoupling Protein 1.

J Obes Metab Syndr 2021 Mar;30(1):32-43

Sungkyun Biotech Co., Ltd., Suwon, Korea.

Background: Obesity is a widespread disease and is caused mainly by excessive adipocyte differentiation and fat accumulation. Peroxisome proliferation-activated receptor γ (PPARγ) and CCAAT/enhancer-binding proteins (C/EBP) are major components for regulating adipocyte differentiation. Uncoupling protein 1 (UCP1) is a transmembrane protein that can convert white fat to brown adipose tissue. L. has long been used in East Asia as an herbal drug for anti-oxidant, anti-bacterial, and anti-obesity purposes.

Methods: We investigated the effects of water extracts of (WEAA) in C3H10T1/2, a mesenchymal stem cell line, by measuring the level of intracellular fat accumulation and the expression of genes associated with adipocyte differentiation. We also evaluated anti-obesity effects of WEAA in Zucker rats, a genetic model for the study of obesity, and in Sprague Dawley rats with high-fat diet (HFD)-induced obesity.

Results: In this study, WEAA reduced the expression levels of PPARγ and C/EBPα in C3H10T1/2 cells, as well as the expression of enzymes that regulate fatty acid metabolism. In the Zucker fatty rat model and the HFD-induced obesity rat model, WEAA significantly decreased adipogenic differentiation and white fat accumulation between the scapulae, in contrast to the brown fat that remained unchanged between the groups. suppressed the expression of the adipocyte differentiation-promoting genes, while increasing the expression of UCP1.

Conclusion: These results indicated that WEAA could reduce adipocyte differentiation and fat accumulation in and model systems, resulting in suppression of obesity and the occurrence of fatty liver due to a HFD.
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http://dx.doi.org/10.7570/jomes20097DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8017327PMC
March 2021

Compressed sensing time-of-flight magnetic resonance angiography with high spatial resolution for evaluating intracranial aneurysms: comparison with digital subtraction angiography.

Neuroradiol J 2021 Jan 18:1971400920988099. Epub 2021 Jan 18.

Siemens Healthineers, Korea.

Background And Purpose: Compressed sensing is used for accelerated acquisitions with incoherently under-sampled k-space data, and intracranial time-of-flight magnetic resonance angiography is suitable for compressed sensing. Compressed sensing time-of-flight is beneficial in decreasing acquisition time and increasing spatial resolution while maintaining acquisition time. In this retrospective study, we aimed to evaluate the image quality and diagnostic performance of compressed sensing time-of-flight with high spatial resolution and compare with parallel imaging time-of-flight using digital subtraction angiography as a reference.

Material And Methods: In total, 39 patients with 46 intracranial aneurysms underwent parallel imaging and compressed sensing time-of-flight in the same imaging session and digital subtraction angiography before or after magnetic resonance angiography. The overall image quality, artefacts and diagnostic confidence were assessed by two observers. The contrast ratio, maximal aneurysm diameters and diagnostic performance were evaluated.

Results: Compressed sensing time-of-flight showed significantly better overall image quality, degree of artefacts and diagnostic confidence in both observers, with better inter-observer agreement. The contrast ratio was significantly higher for compressed sensing time-of-flight than for parallel imaging time-of-flight in both observers (source images,  0.001; maximum intensity projection images,  < 0.05 for both observers); however, the measured maximal diameters of aneurysms were not significantly different. Compressed sensing time-of-flight showed higher sensitivity, specificity, accuracy and positive and negative predictive values for detecting aneurysms than parallel imaging time-of-flight in both observers, with better inter-observer agreement. Compressed sensing time-of-flight was preferred over parallel imaging time-of-flight by both observers; however, parallel imaging time-of-flight was preferred in cases of giant and large aneurysms.

Conclusions: Compressed sensing-time-of-flight provides better image quality and diagnostic performance than parallel imaging time-of-flight. However, neuroradiologists should be aware of under-sampling artefacts caused by compressed sensing.
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http://dx.doi.org/10.1177/1971400920988099DOI Listing
January 2021

In vitro hepatic steatosis model based on gut-liver-on-a-chip.

Biotechnol Prog 2021 Jan 3:e3121. Epub 2021 Jan 3.

Department of Chemical Engineering, Hongik University, Seoul, Republic of Korea.

Hepatic steatosis, also known as fatty liver disease, occurs due to abnormal lipid accumulation in the liver. It has been known that gut absorption also plays an important role in the mechanism underlying hepatic steatosis. Conventional in vitro cell culture models have limitations in recapitulating the mechanisms of hepatic steatosis because it does not include the gut absorption process. Previously, we reported development of a microfluidic gut-liver chip that can recapitulate the gut absorption of fatty acids and subsequent lipid accumulation in liver cells. In this study, we performed a series of experiments to verify that our gut-liver chip reproduces various aspects of hepatic steatosis. The absorption of fatty acids was evaluated under various culture conditions. The anti-steatotic effect of turofexorate isopropyl (XL-335) and metformin was tested, and both drugs showed different action mechanisms. In addition, the oxidative stress induced by lipid absorption was evaluated. Our results demonstrate the potential of the gut-liver chip for use as a novel, physiologically realistic in vitro model to study fatty liver disease.
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http://dx.doi.org/10.1002/btpr.3121DOI Listing
January 2021

CORM-2-entrapped ultradeformable liposomes ameliorate acute skin inflammation in an ear edema model effective CO delivery.

Acta Pharm Sin B 2020 Dec 10;10(12):2362-2373. Epub 2020 Jun 10.

College of Pharmacy, Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan 15588, Republic of Korea.

The short release half-life of carbon monoxide (CO) is a major obstacle to the effective therapeutic use of carbon monoxide-releasing molecule-2 (CORM-2). The potential of CORM-2-entrapped ultradeformable liposomes (CORM-2-UDLs) to enhance the release half-life of CO and alleviate skin inflammation was investigated in the present study. CORM-2-UDLs were prepared by using soy phosphatidylcholine to form lipid bilayers and Tween 80 as an edge activator. The deformability of CORM-2-UDLs was measured and compared with that of conventional liposomes by passing formulations through a filter device at a constant pressure. The release profile of CO from CORM-2-UDLs was evaluated by myoglobin assay. and anti-inflammatory effects of CORM-2-UDLs were assessed in lipopolysaccharide-stimulated macrophages and TPA-induced ear edema model, respectively. The deformability of the optimized CORM-2-UDLs was 2.3 times higher than conventional liposomes. CORM-2-UDLs significantly prolonged the release half-life of CO from 30 s in a CORM-2 solution to 21.6 min. CORM-2-UDLs demonstrated anti-inflammatory activity by decreasing nitrite production and pro-inflammatory cytokine levels. Furthermore, CORM-2-UDLs successfully ameliorated skin inflammation by reducing ear edema, pathological scores, neutrophil accumulation, and inflammatory cytokines expression. The results demonstrate that CORM-2-UDLs could be used as promising therapeutics against acute skin inflammation.
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http://dx.doi.org/10.1016/j.apsb.2020.05.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7745126PMC
December 2020

An Ensemble-Based Approach to Anomaly Detection in Marine Engine Sensor Streams for Efficient Condition Monitoring and Analysis.

Sensors (Basel) 2020 Dec 18;20(24). Epub 2020 Dec 18.

Department of Industrial Data Engineering, Industrial Data Science and Engineering, Pukyong National University, Busan 48513, Korea.

This study proposes an unsupervised anomaly detection method using sensor streams from the marine engine to detect the anomalous system behavior, which may be a possible sign of system failure. Previous works on marine engine anomaly detection proposed a clustering-based or statistical control chart-based approach that is unstable according to the choice of hyperparameters, or cannot fit well to the high-dimensional dataset. As a remedy to this limitation, this study adopts an ensemble-based approach to anomaly detection. The idea is to train several anomaly detectors with varying hyperparameters in parallel and then combine its result in the anomaly detection phase. Because the anomaly is detected by the combination of different detectors, it is robust to the choice of hyperparameters without loss of accuracy. To demonstrate our methodology, an actual dataset obtained from a 200,000-ton cargo vessel from a Korean shipping company that uses two-stroke diesel engine is analyzed. As a result, anomalies were successfully detected from the high-dimensional and large-scale dataset. After detecting the anomaly, clustering analysis was conducted to the anomalous observation to examine anomaly patterns. By investigating each cluster's feature distribution, several common patterns of abnormal behavior were successfully visualized. Although we analyzed the data from two-stroke diesel engine, our method can be applied to various types of marine engine.
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http://dx.doi.org/10.3390/s20247285DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7765970PMC
December 2020

Comparison of local recurrence after mastectomy for pure ductal carcinoma with close or positive margins: A meta-analysis.

J Cancer Res Ther 2020 Oct-Dec;16(6):1197-1202

Department of Radiation Oncology, Biomedical Research Institute, Pusan National University Hospital and Pusan National University School of Medicine, Busan, Korea.

Background: There is controversy regarding the relationship between margin status and risk of local recurrence (LR) in patients with Ductal carcinoma in situ(DCIS) treated by mastectomy.

Purpose: We sought to assess the LR rates for patients with DCIS breast cancer treated by mastectomy with respect to the resection margin (RM) status.

Materials And Methods: Systematic search of MEDLINE, EMBASE, and Cochrane library published was performed. Studies of pure DCIS breast cancer with treatment of mastectomy and studies that reported surgical RM and LR were included.

Results: A total of 12 retrospective studies were included, encompassing 2902 patients with a mean follow-up of 86.4 months. Overall LR rates were 5.3% (27/508) for positive or close margins and 1.6% (37/2367) for negative margin, and most of the recurrences (93.7%) are invasive cancers. Patients with positive or close margins showed a 3.72-fold (95% confidence interval [CI] = 2.30-6.01,P < 0.01, I = 11%) higher risk of LR than patients with negative margin. Patients with positive margin showed a 2.91-fold (95% CI = 1.14-7.41,P = 0.03, I = 0%) higher risk of LR than patients with close margin. Postmastectomy radiation therapy (RT) was not associated with a decreased risk of LR (Risk ratio 0.50; 95% CI = 0.06-4.08,P= 0.52, I = 0%) in patients with positive or close margins.

Conclusions: The RM status after mastectomy has a great impact on LR. However, the recurrence rate was insufficient to warrant a recommendation for postmastectomy RT in patients with close or positive margins.
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http://dx.doi.org/10.4103/jcrt.JCRT_160_19DOI Listing
February 2021

Metabolomic understanding of pod removal effect in soybean plants and potential association with their health benefit.

Food Res Int 2020 12 16;138(Pt B):109797. Epub 2020 Oct 16.

Division of Food and Nutrition, Chonnam National University, Gwangju 61186, Republic of Korea. Electronic address:

Since natural materials, such as phytochemicals in plants, are increasingly being used for foods and skincare due to their beneficial functions, it is important for developing the cultivation practices to increase the contents of phytochemicals. We here explored metabolite perturbations in the leaves of soybean plants when their pods were removed during growth through H NMR-based metabolomics approach. There were obvious metabolic differences in the leaves between normal and pod-removed soybean plants. High amounts of primary metabolites in pod-removed soybean leaves, including amino acids, sugars, and fatty acids, reflected a delay of leaf senescence caused by pod removal. In particular, amounts of isoflavones, coumestrol, and apigenin derivatives in pod-removed soybean leaves were substantially increased. These were considered as distinct metabolic influences of pod removal in soybean plants. These results indicate that pod removal of soybean plants can induce significant perturbations of various metabolites in their soybean leaves, providing useful information to improve the quality of soybean leaves by increasing amounts of bioactive components.
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http://dx.doi.org/10.1016/j.foodres.2020.109797DOI Listing
December 2020

Water Extract of L. Exhibits Hepatoprotective Effects Through Improvement of Lipid Accumulation and Oxidative Stress-Induced Cytotoxicity.

J Med Food 2020 Dec 17;23(12):1312-1322. Epub 2020 Nov 17.

Department of Biomedical Sciences and Seoul National University College of Medicine, Seoul, Korea.

Nonalcoholic fatty liver disease (NAFLD) is a metabolic liver disease with a complex underlying mechanism that has not been completely understood. Thus, effective and safe drugs for this disease are not yet available. L. is a medicinal plant with potent antimicrobial and antioxidant activities. In this study, we prepared a water extract of (WEAA) and examined its potential for NAFLD treatment. First, we pretreated HepG2 cells (human hepatocarcinoma cell line) with WEAA and then treated the cells with oleic acid or -butylhydroperoxide to examine the effect of WEAA on the lipid accumulation and the cytotoxicity, respectively. WEAA not only inhibited lipid accumulation within HepG2 cells but also protected cells from oxidative stress-mediated damage through the activation of antioxidant enzymes (such as activation of superoxide dismutase and production of glutathione) and its own scavenging activity. Next, to confirm protective effect of the WEAA in , mice were intragastrically administered with WEAA, extract of or water once a day, and simultaneously provided with high-fat diet to induce fatty liver and hepatic steatosis. Oral administration of WEAA ameliorated weight gain and hepatic lipid accumulation in high-fat diet-fed mice. Moreover, the plasma levels of triglyceride, aspartate aminotransferase, and alanine aminotransferase were reduced in the WEAA-treated group. Our findings indicated that WEAA may be a potential intervention for preventing or treating hepatic lipid accumulation and liver damage.
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http://dx.doi.org/10.1089/jmf.2020.4696DOI Listing
December 2020

Surface Plasmon Localization-Based Super-resolved Raman Microscopy.

Nano Lett 2020 12 13;20(12):8951-8958. Epub 2020 Nov 13.

School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, South Korea.

We investigate label-free measurement of molecular distribution by super-resolved Raman microscopy using surface plasmon (SP) localization. Localized SP was formed with plasmonic nanopost arrays (PNAs) for measurement of the molecular distribution in HeLa cells. Compared with conventional Raman microscopy on gold thin films, PNAs induce a localized near-field, which allows for the enhancement of the peak signal-to-noise ratio by as much as 4.5 dB in the Raman shifts. Super-resolved distributions of aromatic amino acids and lipids (C-C stretching and C-H twist mode) as targets in HeLa cells were obtained after image reconstruction. Results show almost 4-fold improvement on average in the lateral precision over conventional diffraction-limited Raman microscopy images. Combined with axial imaging in an evanescent field, the results suggest an improvement in optical resolution due to superlocalized light volume by more than an order of magnitude over that of conventional diffraction-limited Raman microscopy.
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http://dx.doi.org/10.1021/acs.nanolett.0c04219DOI Listing
December 2020

Low Temperature Sealing of Anodized Aluminum Alloy for Enhancing Corrosion Resistance.

Materials (Basel) 2020 Oct 31;13(21). Epub 2020 Oct 31.

Department of Metallurgical Engineering, Pukyong National University, 45, Yongso-ro, Nam-Gu, Busan 48513, Korea.

Sealing as a post treatment of anodized aluminum is required to enhance the corrosion resistance by filling nanopores, which allow the penetration of corrosive media toward the base aluminum. We designed a mixed sealing solution with nickel acetate and ammonium fluoride by modifying traditional nickel fluoride cold sealing. The concentration of mixed sealing solution affected the reaction rate of sealing and corrosion current density of anodized aluminum alloy. The higher concentration of mixed sealing solution improved the sealing rate, which was represented by a decrease of corrosion current density of anodized aluminum alloy. However, a mixed sealing solution with 2/3 concentration of general nickel fluoride sealing solution operated at room temperature showed the lowest corrosion current density compared to traditional methods (e.g., nickel fluoride cold sealing (NFCS) and nickel acetate hot sealing) and other mixed sealing solutions. Moreover, the mixed sealing solution with 2/3 concentration of general NFCS had a lower risk for over sealing, which increases the corrosion current density by excessive dissolution of anodic oxide. Therefore, the mixed sealing solution with optimized conditions designed in this work possibly provides a new method for enhancing the corrosion resistance of anodized aluminum alloys.
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http://dx.doi.org/10.3390/ma13214904DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7662489PMC
October 2020

Exercise Preconditioning Attenuates the Response to Experimental Colitis and Modifies Composition of Gut Microbiota in Wild-Type Mice.

Life (Basel) 2020 Sep 14;10(9). Epub 2020 Sep 14.

College of Sport Science, Sungkyunkwan University, Suwon 16419, Korea.

This study investigated the suppressive effect of exercise preconditioning against colitis induced by high-fat diet (HF) plus dextran sulfate sodium (DSS) in wild-type mice. Male mice (C57BL/6) aged 6 weeks were assigned to standard chow (SC, = 10) or HF ( = 10) or HF followed by DSS (HF+DSS, = 10) or exercise preconditioning (EX) followed by HF+DSS (EX+HF+DSS, = 10) for a total of 15 weeks. After 12 weeks of dietary treatments and/or exercise preconditioning, mice in the DSS groups were subjected to administration of 2 cycles of 5-day DSS (2% w/v) with a 7-day interval between cycles. HF resulted in colitis symptoms and histological changes, infiltration of immunity cells, decreased gut barrier proteins, increased pro-inflammatory and chemotactic cytokines and decreased anti-inflammatory cytokine such as adiponectin, which deteriorated after administration of DSS. Exercise preconditioning alleviated HF+DSS-induced colitis and caused significant modifications in gut microbiota: decreased ( = 0.050) and increased ( = 0.050). The current findings suggest that exercise preconditioning attenuates the severity of HF+DSS-induced colitis in C57BL/6 mice.
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http://dx.doi.org/10.3390/life10090200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7555193PMC
September 2020

Methylglyoxal-Induced Dysfunction in Brain Endothelial Cells via the Suppression of Akt/HIF-1α Pathway and Activation of Mitophagy Associated with Increased Reactive Oxygen Species.

Antioxidants (Basel) 2020 Sep 3;9(9). Epub 2020 Sep 3.

College of Pharmacy Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan 15588, Korea.

Methylglyoxal (MG) is a dicarbonyl compound, the level of which is increased in the blood of diabetes patients. MG is reported to be involved in the development of cerebrovascular complications in diabetes, but the exact mechanisms need to be elucidated. Here, we investigated the possible roles of oxidative stress and mitophagy in MG-induced functional damage in brain endothelial cells (ECs). Treatment of MG significantly altered metabolic stress as observed by the oxygen-consumption rate and barrier-integrity as found in impaired trans-endothelial electrical resistance in brain ECs. The accumulation of MG adducts and the disturbance of the glyoxalase system, which are major detoxification enzymes of MG, occurred concurrently. Reactive oxygen species (ROS)-triggered oxidative damage was observed with increased mitochondrial ROS production and the suppressed Akt/hypoxia-inducible factor 1 alpha (HIF-1α) pathway. Along with the disturbance of mitochondrial bioenergetic function, parkin-1-mediated mitophagy was increased by MG. Treatment of N-acetyl cysteine significantly reversed mitochondrial damage and mitophagy. Notably, MG induced dysregulation of tight junction proteins including occludin, claudin-5, and zonula occluden-1 in brain ECs. Here, we propose that diabetic metabolite MG-associated oxidative stress may contribute to mitochondrial damage and autophagy in brain ECs, resulting in the dysregulation of tight junction proteins and the impairment of permeability.
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http://dx.doi.org/10.3390/antiox9090820DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7554889PMC
September 2020

Diagnostic performance of neuromelanin-sensitive magnetic resonance imaging for patients with Parkinson's disease and factor analysis for its heterogeneity: a systematic review and meta-analysis.

Eur Radiol 2021 Mar 4;31(3):1268-1280. Epub 2020 Sep 4.

Department of Radiology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, 82, Gumi-ro 173beon-gil, Bundang-gu, Seongnam, Gyeonggi, 13620, Republic of Korea.

Objective: To determine the diagnostic performance of neuromelanin-sensitive magnetic resonance imaging discriminating between patients with Parkinson's disease and normal healthy controls and to identify factors causing heterogeneity influencing the diagnostic performance.

Methods: A systematic literature search in the Ovid-MEDLINE and EMBASE databases was performed for studies reporting the relevant topic before February 17, 2020. The pooled sensitivity and specificity values with their 95% confidence intervals were calculated using bivariate random-effects modeling. Subgroup and meta-regression analyses were also performed to determine factors influencing heterogeneity.

Results: Twelve articles including 403 patients with Parkinson's disease and 298 control participants were included in this systematic review and meta-analysis. Neuromelanin-sensitive magnetic resonance imaging showed a pooled sensitivity of 89% (95% confidence interval, 86-92%) and a pooled specificity of 83% (95% confidence interval, 76-88%). In the subgroup and meta-regression analysis, a disease duration longer than 5 and 10 years, comparisons using measured volumes instead of signal intensities, a slice thickness in terms of magnetic resonance imaging parameters of more than 2 mm, and semi-/automated segmentation methods instead of manual segmentation improved the diagnostic performance.

Conclusion: Neuromelanin-sensitive magnetic resonance imaging had a favorable diagnostic performance in discriminating patients with Parkinson's disease from healthy controls. To improve diagnostic accuracy, further investigations directly comparing these heterogeneity-affecting factors and optimizing these parameters are necessary.

Key Points: • Neuromelanin-sensitive MRI favorably discriminates patients with Parkinson's disease from healthy controls. • Disease duration, parameters used for comparison, magnetic resonance imaging slice thickness, and segmentation methods affected heterogeneity across the studies.
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http://dx.doi.org/10.1007/s00330-020-07240-7DOI Listing
March 2021

Usefulness of pointwise encoding time reduction with radial acquisition sequence in subtraction-based magnetic resonance angiography for follow-up of the Neuroform Atlas stent-assisted coil embolization for cerebral aneurysms.

Acta Radiol 2020 Aug 31:284185120952784. Epub 2020 Aug 31.

Department of Neurosurgery, Inje University Haeundae Paik Hospital, Busan, Republic of Korea.

Background: Although time-of-flight magnetic resonance angiography (TOF-MRA) is widely used, it has limited usefulness for follow-up after stent-assisted coil embolization. Contrast-enhanced MRA (CE-MRA) and ultrashort echo time MRA have been suggested as alternative methods for visualization after this procedure.

Purpose: To compare efficacy and usefulness of pointwise encoding time reduction with radial acquisition (PETRA) sequence in subtraction-based MRA (qMRA), TOF-MRA, and CE-MRA during the follow-up after Neuroform Atlas stent-assisted coil embolization for intracranial aneurysms.

Material And Methods: This retrospective study included 23 patients with 24 aneurysms who underwent Neuroform Atlas stent-assisted coil embolization for intracranial aneurysms. All patients were evaluated with PETRA qMRA, TOF-MRA, and CE-MRA at the same follow-up session. The flow within stents, occlusion status, and presence of pseudo-stenosis were evaluated; inter-observer and intermodality agreements for the three methods were also graded.

Results: The mean score for flow visualization within the stents was significantly higher for PETRA qMRA and CE-MRA than for TOF-MRA (although no significant difference was found between PETRA qMRA and CE-MRA). Good inter-observer agreement was observed for each modality. PETRA qMRA and CE-MRA were more consistent with digital subtraction angiography (DSA) than TOF-MRA for aneurysm occlusion status. The intermodality agreement was better between PETRA qMRA and DSA, and between CE-MRA and DSA, than between DSA and TOF-MRA. Pseudo-stenosis was most frequently observed in TOF-MRA, followed by CE-MRA and PETRA qMRA.

Conclusion: PETRA qMRA is useful for evaluating the parent artery patency and occlusion status of aneurysms after Neuroform Atlas stent-assisted coil embolization.
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http://dx.doi.org/10.1177/0284185120952784DOI Listing
August 2020

Analysis of circulating-microRNA expression in lactating Holstein cows under summer heat stress.

PLoS One 2020 31;15(8):e0231125. Epub 2020 Aug 31.

Department of Animal and Dairy Sciences, Chungnam National University, Daejeon, Republic of Korea.

Korean peninsula weather is rapidly becoming subtropical due to global warming. In summer 2018, South Korea experienced the highest temperatures since the meteorological observations recorded in 1907. Heat stress has a negative effect on Holstein cows, the most popular breed of dairy cattle in South Korea, which is susceptible to heat. To examine physiological changes in dairy cows under heat stress conditions, we analyzed the profiles circulating microRNAs isolated from whole blood samples collected under heat stress and non-heat stress conditions using small RNA sequencing. We compared the expression profiles in lactating cows under heat stress and non-heat stress conditions to understand the regulation of biological processes in heat-stressed cows. Moreover, we measured several heat stress indicators, such as rectal temperature, milk yield, and average daily gain. All these assessments showed that pregnant cows were more susceptible to heat stress than non-pregnant cows. In addition, we found the differential expression of 11 miRNAs (bta-miR-19a, bta-miR-19b, bta-miR-30a-5p, and several from the bta-miR-2284 family) in both pregnant and non-pregnant cows under heat stress conditions. In target gene prediction and gene set enrichment analysis, these miRNAs were found to be associated with the cytoskeleton, cell junction, vasculogenesis, cell proliferation, ATP synthesis, oxidative stress, and immune responses involved in heat response. These miRNAs can be used as potential biomarkers for heat stress.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0231125PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7458322PMC
September 2020

Direct replication of a glass micro Fresnel zone plate array by laser irradiation using an infrared transmissive mold.

Opt Express 2020 Jun;28(12):17468-17480

It is not yet possible to fabricate micrometer-scale, glass optical components with nanometer-scale precision. Glass thermal imprinting enhances production efficiency. However, dimensional changes caused by shrinkage are inevitable because of phase transitions. Replication is very difficult when high-level pitch precision is essential. We used an infrared-transparent silicon mold and a CO laser to perform replica-type, thermal surface texturing at the nanoscale level; we analyzed a glass Fresnel zone plate array to this end. The Fresnel zone plate array was 10 × 10 mm in area and featured a 20 × 20 array. The individual Fresnel zone plate diameter was 500 µm and had 21 rings of minimum linewidth 2.9 µm and height 737 nm.
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http://dx.doi.org/10.1364/OE.387213DOI Listing
June 2020

Assessing the efficacy of dissolved air and flash-pressurized flotations using low energy for the removal of organic precursors and disinfection byproducts: a pilot-scale study.

Environ Sci Pollut Res Int 2020 Jun 25. Epub 2020 Jun 25.

Department of Civil and Environmental Engineering, Dankook University, 152, Jukjeon-ro, Suji-gu, Yongin-si, Gyeonggi-do, 16890, Republic of Korea.

Dissolved air flotation (DAF) is a widely used treatment process in drinking water and wastewater treatment plants despite high energy cost associated with operation and maintenance (accounts 50% of the total annual operation cost). In recent years, the focus has been diverted to optimizing or reducing energy, and a microbubble generation without a saturator was developed and used in small treatment facilities because of its simple structure. Thus, in this study, DAF and low-energy flash-pressurized flotation (FPF) efficacies were investigated in a pilot plant based on organic precursors, different molecular weight (MW) fractions, and disinfection byproduct reduction. The organic fractions with different MW was analyzed by liquid chromatography-organic carbon detector. Both DAF (550 kPa) and FPF (300 kPa) showed similar removal of dissolved organic carbon (DOC) and chromatographic DOC; however, the removal tendency of different MW fractions found was different. There was no significant difference in the removal of biopolymers, building blocks, and low molecular weight (LMW) neutrals for both DAF and FPF. Interestingly, the removal of LMW acids was found to be higher (93.8%) for DAF, whereas only 35.8% removal was observed for FPF. The total trihalomethanes concentration in a DAF-treated water sample was found to be 10% lower than that of FPF. Also, the reduction in haloacetonitriles was found to be slightly higher for a water sample treated by using DAF than by using FPF (1.5 and 1.8 μg L, respectively). Moreover, the formation of chloral hydrate was observed to be the same (1.9 μg L) for DAF- and FPF-treated water, with a total reduction of 40.6%. FPF with low pressure enabled a reduction in energy of around 55% when compared with DAF. Thus, FPF with low-pressure energy provides an alternative to DAF by reducing the annual operation cost and carbon footprint.
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http://dx.doi.org/10.1007/s11356-020-09820-yDOI Listing
June 2020

Reduction of random telegraph noise by high-pressure deuterium annealing for p-type omega-gate nanowire FET.

Nanotechnology 2020 Oct 19;31(41):415201. Epub 2020 Jun 19.

ICT Convergence Technology for Health & Safety and Department of Electronics and Information Engineering, Korea University, 2511 Sejong-ro, Sejong, Korea (the Republic of.

In this work, we studied the effect of high-pressure deuterium annealing (HPDA) on a p-type omega-gate nanowire field effect transistor by random telegraph noise (RTN) signal analysis. After HPDA under conditions of 400 °C and 10 atm for 30 min, I decreases by 41.2% and I increases by up to 5.4%. Also, subthreshold swing (SS) is reduced from 72 mV dec to 70 mV dec. In RTN analysis, multi-level RTN is reduced to single-level RTN due to the passivation of a fast trap site by HPDA. ΔI/I is also decreased 1.3 and 1.1 times at |V| = 0.2 V and 0.4 V, respectively. From the low-frequency noise analysis, the reduction of trap density is observed by 86% at |V| = 0.4 V after HPDA. Through these results, we found that the HPDA reduces traps of gate dielectric and improves the quality of the interface between gate dielectric and NW channel in p-type OGNW FET.
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http://dx.doi.org/10.1088/1361-6528/ab9e90DOI Listing
October 2020

Machine learning-based design of meta-plasmonic biosensors with negative index metamaterials.

Biosens Bioelectron 2020 Sep 30;164:112335. Epub 2020 May 30.

School of Electrical and Electronic Engineering, Yonsei University, Seoul, 03722, Republic of Korea. Electronic address:

In this work, we explore the performance of plasmonic biosensor designs that integrate metamaterials based on machine learning algorithms. The meta-plasmonic biosensors were designed for optimized detection of DNA with a layer of double negative metamaterial modeled by an effective medium. An iterative transfer matrix approach was employed to generate training and test sets of resonance characteristics in the parameter space for machine learning. As a machine learning-based prediction of optical characteristics of a meta-plasmonic biosensor, multilayer perceptron and autoencoder (AE) were used as an algorithm, while the clustering algorithm was constructed by dimensional reduction based on AE and t-Stochastic Neighbor Embedding (t-SNE) as well as k-means clustering. Use of meta-plasmonic structure with analysis based on machine learning has found that enhancement of detection sensitivity by more than 13 times over conventional detection should be achievable with excellent reflectance curves. Further enhancement may be attained by expanding the parameter space.
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http://dx.doi.org/10.1016/j.bios.2020.112335DOI Listing
September 2020

Involuntary Weight Loss and Late-Life Depression in Korean Older Adults.

Iran J Public Health 2020 Apr;49(4):637-644

College of Sport Science, Sungkyunkwan University, Suwon, Republic of Korea.

Background: To investigate the association between involuntary weight loss (IWL) and late-life depression (LLD) in a population-based cohort study.

Methods: Data (N=6945) obtained from the 2008 baseline and 2011 follow-up assessments of the Living Profiles of Older People Survey in Korea were used. Changed body weight between the 2008 and 2011 was classified into stable weight (<-5% ∼ <+5%), lightweight loss (≥ -5% ∼ <-10%), moderate weight loss (≥ -10%), lightweight gain (+≥5 ∼ <+10%), and moderate weight gain (≥+10%).

Results: Compared to the stable weight group, the moderate weight loss group had a higher risk of LLD (odds ratio=1.99, 95% confidence interval=1.61-2.46, <0.001) even after adjustments for covariates, including age, BMI, education, income, life of solitude, smoking, physical activity, dependent aging, comorbidity, and cognitive function.

Conclusion: IWL is significantly associated with LLD in Korean older adults, implying the prognostic importance of IWL for presenting mental health issues later in life.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7283192PMC
April 2020