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Recent research progress on magnesium alloys in Korea:A review

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Journal of Magnesium and Alloys 2023年第10期11卷 3545-3584页

作者： Sung Hyuk Park Ye Jin kim Hyun Ji kim Sang-Cheol Jin Jong Un Lee Alexander Komissarov Kwang seon Shin School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Laboratory of Hybrid Nanostructured Materials National University of Science and TechnologyMoscow 119049Russia Laboratory of Medical Bioresorption and Bioresistance Moscow State University of Medicine and DentistryMoscow 127473Russia Magnesium Technology Innovation Center School of Materials Science and EngineeringSeoul National UniversitySeoul 08826Republic of Korea

This review highlights the recent advancements in Mg research in South Korea with a prime focus on high-speed-extrudable Mg–Bi-based alloys for high productivity and strength,innovative techniques utilizing{10–12}twinning for improved mechanical properties,and alloying and processing methods for enhanced corrosion ***-alloyed Mg–Bi-based alloys possess thermally stableα-Mg matrix and secondary phase,which ensures high-speed extrusion of these alloys at elevated temperatures without hot ***,they exhibit outstanding extrudability with a maximum extrusion speed of up to 70 m/***,their high alloying contents offer excellent strength even after high-speed extrusion through strong solid solution hardening and particle hardening effects,making them suitable for high-performance extruded Mg *** pre-twinning process utilizing{10–12}twinning and the combined process of pre-twinning and subsequent annealing have shown promise in controlling microstructure and texture of wrought Mg alloys and thus enhancing their mechanical *** pre-twinning process enhances tensile strength,fatigue properties,and age-hardening rate of Mg ***,the combined processes of pre-twinning and subsequent annealing considerably improve their ductility,stretch formability,bending formability,and damping *** have been made to improve the corrosion resistance of Mg alloys through alloying additions,process treatments,and surface *** elements like Ca,Sc,and Sm alter the microstructural features(such as secondary phases and grain size)that affect the corrosion *** treatments such as multidirectional forging,screw rolling,and pulse electron beam can also improve the corrosion resistance by refining the ***,advanced surface coating technologies can create durable and corrosion-resistant layers for effectively protecting the Mg *** these research activities conducted

关键词： South Korea Mg–Bi alloys {10–12}twinning Corrosion Mechanical properties

Association of low muscle strength with metabolic dysfunctionassociated fatty liver disease:A nationwide study

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World Journal of Gastroenterology 2023年第45期29卷 5962-5973页

作者： Gyu Bae Lee Youn Huh Sang Hyun Lee Byoungduck Han Yang-Hyun kim Do-Hoon kim seon Mee kim Youn seon Choi Kyung Hwan Cho Ga Eun Nam Department of Family Medicine Korea University College of MedicineSeoul 02841South Korea Department of Family Medicine Uijeongbu Eulji Medical CenterEULJI UniversityDaejeon 11759South Korea School of Electrical Engineering Korea UniversitySeoul 02841South Korea

BACKGROUND There is limited evidence regarding the association between muscle strength and metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the association between muscle strength and MAFLD in the general population in *** This nationwide representative cross-sectional study included 31649 individuals aged≥19 years who participated in the Korea National Health and Nutrition Examination Survey between 2015 and *** ratios(ORs)and 95%confidence intervals(95%CIs)for MAFLD according to sex-specific quartiles of muscle strength,defined by relative handgrip strength,were calculated using multivariable logistic regression ***,multivariable logistic regression analysis was used to assess the association between muscle strength and probable liver fibrosis in patients with *** Of all the participants,29.3%had *** prevalence of MAFLD was significantly higher in the lower muscle strength quartile groups for all participants,sexes,and age groups(P<0.001).A 1.92-fold(OR=1.92,95%CI:1.70–2.16)and 3.12-fold(OR=3.12,95%CI:2.64–3.69)higher risk of MAFLD was observed in the lowest quartile(Q1)group than in the other groups(Q2–Q4)and the highest quartile(Q4)group,*** ORs of MAFLD were significantly increased in the lower muscle strength quartile groups in a dose-dependent manner(P for trend<0.001).These associations persisted in both *** inverse association between muscle strength and the risk of MAFLD was observed in all subgroups according to age,obesity,and diabetes *** patients with MAFLD,the odds of severe liver fibrosis were higher in Q1(OR=1.83,95%CI:1.25–2.69)than in other groups(Q2–Q4).CONCLUSION Among Korean adults,low muscle strength was associated with an increased risk of MAFLD and liver fibrosis in patients with MAFLD.

关键词： Muscle strength Handgrip strength Metabolic dysfunction-associated fatty liver disease Liver fibrosis Korea National Health and Nutrition Examination Survey

Enhancement parameters of contrast-enhanced computed tomography for pancreatic ductal adenocarcinoma: Correlation with pathologic grading

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World Journal of Gastroenterology 2020年第28期26卷 4151-4158页

作者： Woorim Seo Young Chul kim seon Jeong Min Sang Min Lee Department of Radiology Hallym University Dongtan Sacred Heart HospitalGyeonggi-do 18450South Korea Department of Radiology Hallym University Sacred Heart HospitalGyeonggido 14068South Korea

BACKGROUND Pancreatic ductal adenocarcinoma(PDA)is a malignancy with a high mortality rate and short survival *** conventional computed tomography(CT)has been worldwide used as a modality for diagnosis of PDA,as CT enhancement pattern has been thought to be related to tumor angiogenesis and pathologic grade of *** To evaluate the relationship between the pathologic grade of pancreatic ductal adenocarcinoma and the enhancement parameters of contrast-enhanced *** In this retrospective study,42 patients(Age,mean±SD:62.43±11.42 years)with PDA who underwent surgery after preoperative CT were *** radiologists evaluated the CT images and calculated the value of attenuation at the aorta in the arterial phase and the pancreatic phase(VAarterial and VApancreatic)and of the tumor(VTarterial and VTpancreatic)by finding out four regions of *** between the tumor and the aorta enhancement on the arterial phase and the pancreatic phase(TARarterial and TARpancreatic)was figured out through dividing VT arterial by VAarterial and VTpancreatic by ***-to-aortic enhancement fraction(TAF)was expressed as the ratio of the difference between attenuation of the tumor on arterial and parenchymal images to that between attenuation of the aorta on arterial and pancreatic *** Kruskal-Wallis analysis of variance and Mann-Whitney U test for statistical analysis were *** Forty-two PDAs(23 men and 19 women)were divided into three groups:Welldifferentiated(n=13),moderately differentiated(n=21),and poorly differentiated(n=8).TAF differed significantly between the three groups(P=0.034)but TARarterial(P=0.164)and TARpancreatic(P=0.339)did *** median value of TAF for poorly differentiated PDAs(0.1011;95%CI:0.01100-0.1796)was significantly higher than that for well-differentiated PDAs(0.1941;95%CI:0.1463-0.3194).CONCLUSION Calculation of TAF might be useful in predicting the pathologic grade of PDA.

关键词： Computed tomography Pancreatic ductal carcinoma Diagnostic imaging Clinical pathology Neoplasm grading Prognosis

Bile-derived circulating extracellular mi R-30d-5p and mi R-92a-3p as potential biomarkers for cholangiocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 41-50页

作者： Hye Sook Han Mi Jin kim Joung-Ho Han Jieun Yun Hee Kyung kim Yaewon Yang Ki Bae kim seon Mee Park Department of Internal Medicine Chungbuk National University HospitalCheongju 28644Korea Departments of Internal Medicine Chungbuk National University College of MedicineCheongju 28644Korea Department of Pharmaceutical Engineering College of Science EngineeringCheongju UniversityCheongju 28644Korea

Background: Cholangiocarcinoma (CCA) is from cholangiocytes, and therefore bile is a potentially rich source of biomarkers for CCA. The aim of the study was to identify and validate microRNAs (miRNAs) in bile samples that are differentially expressed between benign biliary disease (BBD) and CCA. Methods: Bile samples from 106 patients with obstructive biliary disease were allocated consecutively to a discovery set (10 patients with BBD and 11 with CCA) and then a validation set (48 patients with BBD and 37 with CCA). An miRNA microarray platform was used to screen 1209 miRNAs in the discovery set. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the pro ling results in the discovery and validation sets. In addition, the levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were determined from patient serum samples. Results: Microarray pro ling showed that miR-30d-5p and miR-92a-3p were signi cantly upregulated in bile from the CCA group compared with those from the BBD group. qRT-PCR results indicated that the expression levels of miR-30d-5p and of miR-92a-3p were signi cantly upregulated in the CCA group compared to the BBD group, validating the miRNA microarray results. Pathway analysis suggested that putative target genes of miR-30d-5p and of miR-92a-3p were involved in CCA-associated signalling path- ways, such as Hippo, Wnt, p53, MAPK, and EGFR. Receiver operating curve analysis revealed that the areas under the curve for bile miR-30d-5p, miR-92a-3p, serum CA19-9, and CEA were 0.730, 0.652, 0.675, and 0.603, respectively, and bile miR-30d-5p showed the best diagnostic performance with a sensitivity of 81.1% and a speci city of 60.5%. Conclusions: The levels of extracellular miR-30d-5p and miR-92a-3p in bile were signi cantly higher in patients with CCA than those in patients with BBD. Bile-derived circulating extracellular miR-30d-5p and miR-92a-3p are potential biomarkers for discr

关键词： Bile Biomarkers Cholangiocarcinoma MicroRNA

Predicting Bitcoin Trends Through Machine Learning Using Sentiment Analysis with Technical Indicators

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Computer Systems Science & Engineering 2023年第8期46卷 2231-2246页

作者： Hae Sun Jung seon Hong Lee Haein Lee Jang Hyun kim Department of Applied Artificial Intelligence/Department of Human-Artificial Intelligence Interaction Sungkyunkwan UniversitySeoul03063Korea Department of Interaction Science/Department of Human-Artificial Intelligence Interaction Sungkyunkwan UniversitySeoul03063Korea

Predicting Bitcoin price trends is necessary because they represent the overall trend of the cryptocurrency *** the history of the Bitcoin market is short and price volatility is high,studies have been conducted on the factors affecting changes in Bitcoin *** have been conducted to predict Bitcoin prices using Twitter ***,the amount of data was limited,and prices were predicted for only a short period(less than two years).In this study,data from Reddit and LexisNexis,covering a period of more than four years,were *** data were utilized to estimate and compare the performance of the six machine learning techniques by adding technical and sentiment indicators to the price data along with the volume of *** accuracy of 90.57%and an area under the receiver operating characteristic curve value(AUC)of 97.48%were obtained using the extreme gradient boosting(XGBoost).It was shown that the use of both sentiment index using valence aware dictionary and sentiment reasoner(VADER)and 11 technical indicators utilizing moving average,relative strength index(RSI),stochastic oscillators in predicting Bitcoin price trends can produce significant ***,the input features used in the paper can be applied on Bitcoin price ***,this approach allows investors to make better decisions regarding Bitcoin-related investments.

关键词： Bitcoin cryptocurrency sentiment analysis price trends prediction natural language processing machine learning

A case study of environmental characteristics on urban road-surface and air temperatures during heat-wave days in Seoul

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Atmospheric and Oceanic Science Letters 2019年第4期12卷 261-269页

作者： kim Yoo-Jun kim Baek-Jo SHIN Yoon-Sook kim Hui-Won kim Geon-Tae kim seon-Jeong High Impact Weather Research Center National Institute of Meteorological Sciences

High road-surface temperature due to heat waves can lead to dangerous driving conditions such as tire blowouts and deformation induced by thermal stress on the roads. In this study, a Mobile Observation Vehicle dataset, with high spatial and temporal resolutions for the heat-wave episode that occurred on 16–17 August 2018, is used to understand environmental characteristics on urban road-surface and air temperatures in Seoul. This study demonstrates that the magnitude of urban road-surface temperature is dependent on the differences in incoming solar radiation due to screening of high-rise buildings in the Gangnam area, and is associated with the topographical features in the Gangbuk area. The road-surface temperature in the section of darker-colored asphalts was higher than that of lighter-colored asphalts, with a mean difference of 6.8°C, and both surface and air temperatures on the iron plate were highest, with means of 51.7°C and 35.1°C,respectively. In addition, during the water-sprinkling period, road-surface temperature was cooled by about 8.7°C(19%) compared with that in the period without water-sprinkling, but there was no significant change in air temperature. The current results could be practically used to improve roadsurface temperature prediction models for civil engineers or road managers.

关键词： Heat wave road-surface temperature mobile observation vehicle Seoul

Underwater endoscopic mucosal resection for neoplasms in the pyloric ring of the stomach: Four case reports

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World Journal of Clinical Cases 2020年第14期8卷 3050-3056页

作者： Dong Hyun kim seon-Young Park Chang Hwan Park Hyun Soo kim Sung Kyu Choi Division of Gastroenterology Department of Internal MedicineChonnam National University Hospital and Medical SchoolGwangju 61469South Korea

BACKGROUND Tumors located in the pylorus are technically more complex to resect by endoscopic resection,as the anatomical characteristics of this region can affect the adequate assessment of margins and performance of the *** reported the results of underwater endoscopic mucosal resection(UEMR)of benign mucosal neoplasms located in the pyloric *** SUMMARY This case series describes 4 patients with 4 mucosal neoplasms located in the pyloric *** diameter of each neoplasm was less than 15 *** performed UEMR for the *** immersion enabled slight floating of the lesions,resulting in easy *** achieved en bloc resection with a snare and electrosurgical *** procedure were performed within 3 min without adverse *** examination showed low-grade dysplasia with clear resection margins in one case and hyperplastic polyps in three *** UEMR can be an effective and safe treatment method for neoplasms in the gastric pyloric ring.

关键词： Duodenoscopy Endoscopic mucosal resection Neoplasm Pylorus Stomach Case report

Diagnostic accuracy of administrative database for bile duct cancer by ICD-10 code in a tertiary institute in Korea

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Hepatobiliary & Pancreatic Diseases International 2020年第6期19卷 575-580页

作者： Young-Jae Hwang seon Mee Park Soomin Ahn Jongchan Lee Young Soo Park Nayoung kim Department of Internal Medicine Seoul National University Bundang HospitalSeongnamKorea Department of Internal Medicine Chungbuk National University College of Medicine and Medical Research InstituteCheongjuKorea Department of Pathology Seoul National University Bundang HospitalSeoungnamKorea Department of Internal Medicine and Institute of Liver Research Seoul National University College of MedicineSeoulKorea Tumor Microenvironment Global Core Research Center Seoul National UniversitySeoulKorea

Background:Administrative database provides valuable information for large cohort studies,especially when tissue diagnosis is rather difficult such as the diagnosis for bile duct cancer(BDC).The aim of this study was to evaluate the diagnostic accuracy of administrative database for BDC by International Classification of Diseases(ICD)-10 codes in a tertiary ***:BDC and control groups were collected from 2003 to 2016 at Seoul National University Bundang *** of BDC were identified in the National Health Insurance Service(NHIS)database by ICD 10-code supported by V *** control group was selected from cases without ICD-10 codes for BDC.A definite or possible diagnosis was defined according to pathologic *** records,images,and pathology reports were analyzed to evaluate ICD-10 codes for ***,specificity,positive predictive value,and negative predictive value for BDC were analyzed according to diagnostic criteria and cancer ***:A total of 1707 patients with BDC and 1707 controls were *** those with BDC,1320(77.3%)were diagnosed by definite ***(99.4%)of them had *** of definite diagnosis was the highest for ampulla of Vater(88.9%),followed by that for extrahepatic(84.9%)and intrahepatic(68.3%)*** positive cases commonly had hepatocellular *** overall diagnosis of BDC,sensitivity,specificity,positive predictive value,and negative predictive value were 99.94%,98.33%,98.30%,and 99.94%,*** accuracies were similar regardless of diagnostic criteria or tumor ***:Administrative database for BDC collected according to ICD-10 code with V code shows good accuracy.

关键词： National Health Insurance Service Bile duct cancer ICD-10

Effect of organic mineral supplementation in reducing oxidative stress in Holstein calves during short‑term heat stress and recovery conditions

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Journal of Animal Science and Biotechnology 2024年第2期15卷 812-825页

作者： A-Rang Son seon-Ho kim Mahfuzul Islam Michelle Miguel Ye Pyae Naing Sang-Suk Lee Ruminant Nutrition and Anaerobe Laboratory Department of Animal Science and TechnologySunchon National UniversitySuncheon 57922Korea Department of Microbiology and Parasitology Sher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh

Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)during short-term heat stress(HS)and recovery *** Holstein calves were randomly assigned to four treatment groups:no mineral supplementation(Con),inorganic minerals(IM),organic minerals(OM),and high-concentration organic minerals(HOM)and two thermal environments(HS and recovery)using 4×2 factorial arrangement in a crossover design of four periods of 35 *** were maintained in a temperature-controlled *** experimental period consisted of 14 d of HS,14 d of recovery condititon,and a 7-d washing *** Body temperature and respiration rate were higher in HS than in the recovery conditions(P0.05).The principal coordinate analysis represented that the overall rumen microbiota was not influenced by mineral supplementation;however,temperature-induced microbial structure shifts were indicated(PERMANOVA:P<0.05).At the phylum level,Firmicutes and Actinobacteria decreased,whereas Fibrobacteres,Spirochaetes,and Tenericutes increased(P<0.05),under HS *** genus Treponema increased under HS conditions,while Christensenella was higher in recovery conditions(P<0.05).Conc

关键词： Antioxidant status Heat stress Holstein bull calves Organic mineral supplementation Oxidative stress