YOUNG TABLEAUX, CANONICAL BASES, AND THE GINDIKIN-KARPELEVICH FORMULA

Lee, Kyu-Hwan,Salisbury, Ben Korean Mathematical Society 2014 대한수학회지 Vol.51 No.2

A combinatorial description of the crystal $\mathcal{B}({\infty})$ for finite-dimensional simple Lie algebras in terms of certain Young tableaux was developed by J. Hong and H. Lee. We establish an explicit bijection between these Young tableaux and canonical bases indexed by Lusztig's parametrization, and obtain a combinatorial rule for expressing the Gindikin-Karpelevich formula as a sum over the set of Young tableaux.

A Report on a Nationwide Surveillance System for Pediatric Acute Hepatitis of Unknown Etiology in Korea

Lee Kyung Jae,Ko Jae Sung,Park Kie Young,Kang Ki Soo,Lee Kunsong,Hong Jeana,Kim Soon Chul,Lee Yoon,Kang Ben,Kim Yu Bin,Kim Hyun Jin,Eun Byung Wook,Cho Hye-Kyung,Kim Yae-Jean,Kim Mi Jin,Lee Jin,Lee Tae 대한의학회 2023 Journal of Korean medical science Vol.38 No.47

Background: Several cases of pediatric acute hepatitis of unknown etiology related to adenoviral infections have been reported in Europe since January 2022. The aim of this study was to compare the incidence, severity, possible etiology, and prognosis of the disease with those in the past in Korea. Methods: The surveillance group collected data between May and November 2022 using a surveillance system. Acute hepatitis of unknown etiology was defined in patients aged < 16 years with a serum transaminase level > 500 IU/L, not due to hepatitis A-E or other underlying causes. For comparison, data from 18 university hospitals were retrospectively collected as a control group between January 2021 and April 2022. Results: We enrolled 270 patients (mean age, 5 years). The most common symptom was fever. However, the incidence was similar between 2021 and 2022. Liver function test results, number of patients with acute liver failure (ALF), liver transplantation (LT), death, and adenovirus detection rates did not differ between the two groups. None of the adenoviruspositive patients in either group experienced ALF, LT, or death. In the surveillance group, adenovirus-associated virus-2 was detected in four patients, one of whom underwent LT. Patients with an unknown etiology showed significantly higher bilirubin levels, a lower platelet count, and a higher LT rate than patients with a possible etiology. Conclusion: The incidence of pediatric acute hepatitis of unknown etiology and adenovirus detection rate have not increased in Korea.

Korean Children and Adolescents with Crohn's Disease Are More Likely to Present with Perianal Fistulizing Disease at Diagnosis Compared to Their European Counterparts

Kang, Ben,Kim, Jung Eun,Jung, Jae Hun,Choe, Jae Young,Kim, Mi Jin,Choe, Yon Ho,Kim, Seung,Koh, Hong,Lee, Yoo Min,Lee, Jee Hyun,Lee, Yoon,Lee, Ji-Hyuk,Lee, Hae Jeong,Jang, Hyo-Jeong,Choi, Youjin,Choi, The Korean Society of Pediatric Gastroenterology 2020 Pediatric gastroenterology, hepatology & nutrition Vol.23 No.1

Purpose: We aimed to investigate the disease phenotype of Korean pediatric Crohn's disease (CD) patients at diagnosis according to the Paris classification by comparison with patients from the European multicenter 5-years recruitment of children with newly developed IBD (EUROKIDS registry). Methods: Korean children and adolescents who had been newly diagnosed with CD at the age of <18 years during 2013-2016 were included in this multicenter retrospective study. Disease phenotype at diagnosis was classified according to the Paris classification, and compared with the published data from the EUROKIDS study. Results: A total of 255 patients were included. The median diagnosis age was 14.7 years (range, 0.8-17.9 years). No significant difference was observed in male-to-female ratio with EUROKIDS (1.9:1 vs. 1.45:1, p=0.062). The proportion of children aged <10 years was significantly lower in Koreans (7.1% vs. 19.6%, p<0.001). Colonic disease was less prominent (10.0% vs. 27.3%, p<0.001), while upper GI involvement was more prominent in Korean children (59.3% vs. 46.2%, p<0.001). The proportion with perianal fistulizing disease at diagnosis was significantly higher in Korean patients (44.8% vs. 8.2%, p<0.001). A separate analysis of Korean patients revealed that perianal fistulizing disease at diagnosis was positively associated with male sex and body mass index z-score (odds ratio [OR]=2.12, 95% confidence interval [CI]=1.20-3.76, p=0.010; and OR=1.29, 95% CI=1.05-1.58, p=0.015, respectively). Conclusion: Approximately half of pediatric CD patients in Korea present with perianal fistulas and/or abscesses at diagnosis, which is a distinct feature of CD in Korean children and adolescents compared to their European counterparts. An underlying genetic difference between ethnicities may play a role in this expression of different phenotypes in pediatric CD.

OEFMON: An open evaluation framework for multimedia over networks

Chunho Lee,Myungchul Kim,Hyun, S. J.,Sooyong Lee,Ben Lee,Kyounghee Lee IEEE 2011 IEEE communications magazine Vol.49 No.9

<P>As various types of networks are proliferating with greater capacity, the demand for multimedia services, such as videoconferencing, VoIP, and IPTV, over underlying networks has been increasing. This demand has increased the need for an evaluation framework to analyze the quality of such multimedia services and network performances for the related research areas. This article proposes OEFMON, an open framework for evaluating the quality of multimedia transmissions over networks. OEFMON integrates a multimedia module and a network simulator. The major advantages of OEFMON compared to other existing work are support for any number of multimedia codecs, adaptive coding based on network feedback, on-the-fly observation of multimedia transmission, and easy extension for other tools. A couple of case studies are performed to demonstrate the applicability and usefulness of our framework.</P>

Nationwide “Pediatric Nutrition Day” survey on the nutritional status of hospitalized children in South Korea

Yoo Min Lee,Eell Ryoo,Jeana Hong,Ben Kang,Byung-Ho Choe,Ji-Hyun Seo,Ji Sook Park,Hyo-Jeong Jang,Yoon Lee,Eun Jae Chang,Ju Young Chang,Hae Jeong Lee,Ju Young Kim,Eun Hye Lee,Hyun Jin Kim,Ju-Young Chung 한국영양학회 2021 Nutrition Research and Practice Vol.15 No.2

BACKGROUND/OBJECTIVES: To evaluate the nutritional status and prevalence of malnutrition in hospitalized children at admission and during hospitalization in South Korea. SUBJECTS/METHODS: This first cross-sectional nationwide “Pediatric Nutrition Day (pNday)” survey was conducted among 872 hospitalized children (504 boys, 368 girls; 686 medical, 186 surgical) from 23 hospitals in South Korea. Malnutrition risk was screened using the Pediatric Yorkhill Malnutrition Score (PYMS) and the Screening Tool Risk on Nutritional status and Growth. Nutritional status was assessed by z-scores of weight-for-age for underweight, weight-for-height for wasting, and height-for-age for stunting as well as laboratory tests. RESULTS: At admission, of the 872 hospitalized children, 17.2% were underweight, and the prevalence of wasting and stunting was 20.2% and 17.3%, respectively. During hospitalization till pNday, 10.8% and 19.6% experienced weight loss and decreased oral intake, respectively. During the aforementioned period, fasting was more prevalent in surgical patients (7.5%) than in medical patients (1.6%) (P < 0.001). According to the PYMS, 34.3% and 30% of the children at admission and on pNday, respectively, had a high-risk of malnutrition, requiring consultation with the nutritional support team (NST). However, only 4% were actually referred to the NST during hospitalization. CONCLUSIONS: Malnutrition was prevalent at admission and during hospitalization in pediatric patients, with many children experiencing weight loss and poor oral intake. To improve the nutritional status of hospitalized children, it is important to screen and identify all children at risk of malnutrition and refer malnourished patients to the multidisciplinary NST for proper nutritional interventions.

네트워크 상 멀티미디어를 위한 개방형 평가 프레임워크

이춘호(Chunho Lee),김명철(Myungchul Kim),윤요한(Yohaan Yoon),이일범(Ben Lee),현순주(Soon Joo Hyun),이경희(Kyunghee Lee),이수용(Sooyong Lee) 한국정보과학회 2011 한국정보과학회 학술발표논문집 Vol.38 No.1A

다양한 멀티미디어 서비스의 등장으로, 네트워크를 통한 멀티미디어의 원활한 전송에 대한 요구가 높아지고 있다. 이에 따라 이러한 기술 들을 검증하고 실험하기 위한 멀티미디어와 네트워크의 통합 프레임워크의 필요성은 높아졌다. 따라서, 이 논문에서는 멀티미디어의 네트워크 전송에 관한 연구를 위한 새로운 프레임워크를 제안한다. 본 프레임워크는 멀티미디어 프레임워크를 네트워크 시뮬레이터에 통합하여 멀티미디어 프레임워크에서 지원되는 다양한 멀티미디어 코덱을 시뮬레이터와 연동하여 사용하게 하고 네트워크 상태를 피드백으로 멀티미디어 프레임워크에 주어 수용하게 한다. 이 프레임워크는 기존 연구에 비해 다양한 코덱 지원, 네트워크 피드백기반 멀티미디어 코딩, 실시간 비디오 전송 관찰 등의 장점이 있다. 또한 제안된 프레임워크의개별 연구를 수행하여 그 효용성을 입증하였다.

A Nationwide Survey on Gastrointestinal Endoscopy Practice Patterns among Pediatric Endoscopists in South Korea

Yoo Min Lee,Yoon Lee,So Yoon Choi,Hyun Jin Kim,Suk Jin Hong,Yunkoo Kang,Eun Hye Lee,Kyung Jae Lee,Youjin Choi,Dae Yong Yi,Seung Kim,Ben Kang 대한소아소화기영양학회 2023 Pediatric gastroenterology, hepatology & nutrition Vol.26 No.2

Purpose: Gastrointestinal (GI) endoscopy is an important tool for diagnosing and treating GI diseases in children. This study aimed to analyze the current GI endoscopy practice patterns among South Korean pediatric endoscopists. Methods: Twelve members of the Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition developed a questionnaire. The questionnaire was emailed to pediatric gastroenterologists attending general and tertiary hospitals in South Korea. Results: The response rate was 86.7% (52/60), and 49 of the respondents (94.2%) were currently performing endoscopy. All respondents were performing esophagogastroduodenoscopy, and 43 (87.8%) were performing colonoscopy. Relatively rare procedures for children, such as double-balloon enteroscopy (DBE) (4.1%), endoscopic retrograde cholangiopancreatography (ERCP) (2.0%), and endoscopic ultrasound (EUS) (2.0%), were only performed by pediatric gastroenterologists at very few centers, but were performed by adult endoscopists in most of the centers; of all the respondents, 83.7% (41/49) performed emergency endoscopy. In most centers, the majority of the endoscopies were performed under sedation, with midazolam (100.0%) and ketamine (67.3%) as the most frequently used sedatives. Conclusion: While most pediatric GI endoscopists perform common GI endoscopic procedures, rare procedures, such as DBE, ERCP, and EUS, are only performed by pediatric gastroenterologists at very few centers, and by adult GI endoscopists at most of the centers. For such rare procedures, close communication and cooperation with adult GI endoscopists are required.

Complete sequence-based screening of TPMT variants in the Korean population

Kim, Hyun-Young,Lee, Soo Hyun,Lee, Mi-Na,Kim, Jong-Won,Kim, Young-Ho,Kim, Mi Jin,Lee, Yoo Min,Kang, Ben,Choe, Yon Ho,Lee, Na Hee,Kim, Dong Hwan,Yoo, Keon Hee,Sung, Ki Woong,Lee, Soo-Youn,Koo, Hong Hoe Wolters Kluwer Health, Inc. All rights reserved. 2015 PHARMACOGENETICS AND GENOMICS Vol.25 No.3

Thiopurine S-methyltransferase (TPMT) is a cytoplasmic enzyme involved in the metabolism of thiopurine drugs and its activity is largely influenced by polymorphisms of the TPMT gene. To date, more than 35 TPMT variants are known to be associated with reduced enzyme activity, but most studies on the TPMT genotype have included only common nonfunctional variants, such as TPMT*2 and TPMT*3. In this study, we carried out a complete sequencing analysis to screen all TPMT variants in Korean patients. A total of 900 Korean patients were genotyped for TPMT and 30 patients (3.3%) had the known TPMT variant alleles. TPMT*3C was found in 25 patients (2.8%): 24 patients with TPMT*1/*3 and one with TPMT*3/*3. Rare TPMT variants including TPMT*6, TPMT*16, and TPMT*32 were detected in five patients (0.6%) and a novel variant, TPMT*38 (c.514T>C, p.S172P), was identified in two patients. This is the first complete sequence-based screening study evaluating all TPMT variants in Asian populations.

LAN 패킷 분석을 통한 WWW 이 통신상에 끼치는 영향

(Ben Lee),(Andreas Schmid),고진광(Jin Gwang Koh),곽한탁(Han Tak Kwak) 한국정보처리학회 1999 정보처리학회논문지 Vol.6 No.11

We present new methods for an efficient retrieval of SGML documents. We define IDDL (index database description language) which is able to describe various information such as meta data, an indexing range, and the creation and mainpulation of a database. In addition, we design IDQL (index database query language) that can deal with querying meta data as well as logical structure. Especially, the retrieval system based on IDDL and IDQL has been developed and implemented, and has been experimented on large number of documents. Experimental result show that the proposed method provides the dynamic creation of an index database and a convenient retrieval environment.

Outcome of Alagille Syndrome Patients Who Had Previously Received Kasai Operation during Infancy: A Single Center Study

Lee, Hwa Pyung,Kang, Ben,Choi, So Yoon,Lee, Sanghoon,Lee, Suk-Koo,Choe, Yon Ho The Korean Society of Pediatric Gastroenterology 2015 Pediatric gastroenterology, hepatology & nutrition Vol.18 No.3

Purpose: Infants with Alagille syndrome (AGS) are occasionally misdiagnosed as biliary atresia and subsequently undergo Kasai operation. The purpose of this study was to investigate the outcome of patients with AGS who had previously received Kasai operation during infancy. Methods: This retrospective study was conducted at the Department of Pediatrics, Samsung Medical Center. We compared the prognosis and mortality between those who had undergone Kasai operation during infancy (Kasai group) and those who had not (non-Kasai group). Results: Among the 15 children with AGS, five had received Kasai operation, while 10 had not. All subjects in the Kasai group revealed neonatal cholestasis, while 70% of the non-Kasai group showed neonatal cholestasis. Liver transplantation was performed in 100% (5/5) among the Kasai group, and 20.0% (2/10) among the non-Kasai group (p=0.007). Mortality was observed in 60.0% (3/5) among the Kasai group, and 10.0% (1/10) among the non-Kasai group (p=0.077). Conclusion: Although overall mortality rate did not significantly differ between the two groups, the proportion of patients receiving liver transplantation was significantly higher in the non-Kasai group. The relatively worse outcome in AGS patients who had received Kasai operation may be due to the unfavorable influences of Kasai operation on the clinical course of AGS, or maybe due to neonatal cholestasis, irrespective of the Kasai operation.