Detection of Impact Damage in Composite Plates Using Surface Contact Method

Chun, Heoung Jae,Kim, Dang Won,Byun, Joon Hyung Trans Tech Publications, Ltd. 2006 Key Engineering Materials Vol.326 No.-

<P>It is a well known fact that the fundamental causes of most failures in composite structures are in the forms of incipient damages such as delaminations and cracks which usually remain undetected until they grow to levels large enough to cause failure. In this study, unidirectional carbon/epoxy composite plates with known defects are investigated. The known defects are generated by impacting the composite specimens simulating external collision. A pair of transmitter and receiver was used for generation of Lamb waves and reception of signals. The received signals were monitored by scanning the receiver toward internal defect or by scanning both transmitter and receiver with confined distance over the surface of the composite plates which have known defects lie beneath them. The proper selection of incident angle and frequency are also considered. The characteristics of received signals such as amplitude, energy and wave form are analyzed. The acquired information is used to locate and to measure the size of the impact damage. The suggested method is very effective if the internal damage is presented closed to surface of the plate where the conventional pulse-echo method has problems. The proposed technique can be used widely for the real time and online monitoring of composite structures.</P>

An Evaluation of the Neonatal Immune System Using a <i>Listeria</i> Infection Model

Byun, Hyun-Jung,Jung, Woon-Won,Lee, Jong-Bae,Chung, Hee Yong,Sul, Donggeun,Kim, Sang Joon,Park, Chung-Gyu,Choi, Inho,Hwang, Kwang Woo,Chun, Taehoon S. Karger AG 2007 NEONATOLOGY Vol.92 No.2

<P><I>Background:</I> T helper 1 (Th1)/T helper 2 (Th2)-biased cytokine regulation may be another reason that neonates are much more susceptible to infectious disease than are adults. <I>Objectives:</I> We attempted to determine the ability of neonatal mice to direct the Th1 phenotype against <I>Listeria monocytogenes</I> (LM), because LM, an intracellular Gram-positive bacterium, induces profound cellular immunity by Th1 cells in vivo. <I>Methods:</I> In order to determine whether neonatal mice evidence strong Th1 activity during LM infection, neonatal mice were compared with adult mice with regard to susceptibility to LM, cytotoxic T lymphocyte activity, and cytokine profiles. Neonatal gene profiles relevant to Th1 and Th2 differentiation during LM infection were also compared between neonatal and adult mice, via real-time PCR and RT-PCR. <I>Results:</I> Neonatal mice were found to be far more susceptible to LM infection than adult mice, due to a lack in the induction of cytotoxic T cell activity, coupled with poor IFN-γ secretion. Further, LM-infected neonatal mice evidenced much lower levels of expression of Th1-type immune components, including IL-12, IFN-γ, Delta-4 and T-bet, as compared to those features in adult mice. These results may be due to the comparably lower expressions of mannose-bind lectins and some of toll-like receptors (TLRs) such as TLR-5, -6 and -9, necessary mediators to develop Th1 immune responses. <I>Conclusions:</I> Neonatal mice may not mount an adequate Th1 type immune response due to a significantly lower expression of Th1-type immune components as compared to adult mice, even when forced into a Th1-prone environment.</P><P>Copyright © 2007 S. Karger AG, Basel</P>

Distribution of Malassezia Species on the Scalp in Korean Seborrheic Dermatitis Patients

( Yang Won Lee ),( Hee Jin Byun ),( Beom Joon Kim ),( Dong Ha Kim ),( Yun Young Lim ),( Jin Woong Lee ),( Myeung Nam Kim ),( Dong Hak Kim ),( Young Jin Chun ),( Seog Kyun Mun ),( Chan Woong Kim ),( Su 대한피부과학회 2011 Annals of Dermatology Vol.23 No.2

Background: Malassezia species play an important role in the pathogenesis of seborrheic dermatitis. In particular, M. restricta and M. globosa are considered to be the predominant organisms in seborrheic dermatitis of Western countries. However, species distribution of Malassezia in seborrheic dermatitis has not been clearly determined yet in Asia. Objective: To identify the distribution of Malassezia species on the scalp of seborrheic dermatitis patients in Korea using 26S rDNA PCR-RFLP analysis. Methods: A total of 40 seborrheic dermatitis patients and 100 normal healthy volunteers were included in this study. For the identification of Malassezia species, the scalp scales of the subjects were analyzed by 26S rDNA PCR-RFLP analysis. Results: The most commonly identified Malassezia species were M. restricta in the seborrheic dermatitis patients, and M. globosa in the normal controls. In the seborrheic dermatitis group, M. restricta was identified in 47.5%, M. globosa in 27.5%, M. furfur in 7.5%, and M. sympodialis in 2.5% of patients. In the healthy control group, M. globosa was identified in 32.0%, M. restricta in 25.0%, M. furfur in 8.0%, M. obtusa in 6.0%, M. slooffiae in 6.0%, and M. sympodialis in 4.0% of subjects. Conclusion: M. restricta is considered to be the most im portant Malassezia species in Korean seborrheic dermatitis patients. (Ann Dermatol 23(2) 156∼161, 2011)

Sperm Fertility of Transgenic Boar Harboring hEPO Gene is Decreased

Park Chun-Gyu,Kim Sung-Woo,Lee Poong-Yeon,Han Joo-Hee,Lee Hyun-Gi,Byun Sung-June,Yang Boh-Suk,Lee Chang-Hyung,Lee Hoon-Taek,Chang Won-Kyong,Park Jin-Ki 한국동물생명공학회(구 한국동물번식학회) 2006 Reproductive & developmental biology Vol.30 No.1

This study was conducted to compare the reproduction ability of the wild type boar and recombinant human erythropoietin (hEPO) transgenic boar semen. Ejaculated boar semen was analyzed by flow cytometry, Elisa and IVF methods. In experiment 1, flow cytometric analysis showed that the live sperm ratio of transgenic boar sperm significantly lower (P<0.05) than that of wild type boar after incubation at 20, 22, 24 and 26 hr. In experiment 2, the presence and levels of various cytokines (IL-6, IL-10 and TNF-α) to related animal reproduction in the seminal and blood plasma were examined using specific enzyme immunoassay. There was no significant difference between both groups. In experiment 3, the fertilizing capacity and developmental ability of both boar sperm were compared. The transgenic boar sperm had a significantly low capacity of penetration, sperm-zona binding, embryo development, and blastocyst formation compared to wild type sperm (P<0.05). These results suggest that transgenic boar sperm harboring hEPO gene has low sperm viability than wild type boar, and it is a reason to decrease of fertility and litter size.

Effect of Angiotensin I-Converting Enzyme (ACE) Inhibitory Peptide Purified from Enzymatic Hydrolysates of Styela plicata

Seok-Chun Ko,Min Cheol Kang,Jung-Kwon Lee,Hee-Guk Byun,Se-Kwon Kim,Seung-Cheol Lee,Byong-Tae Jeon,Pyo-Jam Park,Won-Kyo Jung,You-Jin Jeon 한국식품영양과학회 2011 한국식품영양과학회 학술대회발표집 Vol.2011 No.10

Volume and size effects of intermetallic compounds on the high-temperature oxidation behavior of Mo-Si-B alloys

Choi, Won June,Park, Chun Woong,Park, Jung Hyo,Kim, Young Do,Byun, Jong Min Elsevier 2019 INTERNATIONAL JOURNAL OF REFRACTORY METALS AND HAR Vol.81 No.-

<P><B>Abstract</B></P> <P>In this study, we investigated the high-temperature oxidation behavior of Mo-Si-B alloys with different volume fractions or sizes of intermetallic compound phases. Mo-Si-B alloys with uniformly dispersed intermetallic compound phases (Mo<SUB>5</SUB>SIB<SUB>2</SUB> and Mo<SUB>3</SUB>Si) in Mo solid solution matrix phase were fabricated using a novel powder metallurgical route, as introduced in our previous study. An isothermal oxidation test was conducted at 1300 °C for up to 10 h. The high-temperature oxidation resistance of Mo-Si-B alloys improved by increasing the volume fraction of intermetallic compound phases; this was a result of the increased amount of protective oxidized layers, which protect the Mo<SUB>ss</SUB> phase from oxidation by covering the surface. In addition, Mo-Si-B alloy with smaller intermetallic compound phases pulverized by high-energy ball milling had better high-temperature oxidation resistance compared to Mo-Si-B alloy with as-synthesized intermetallic compound phases.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The volume and size effects on intermetallic compound phases on high-temperature of Mo-Si-B alloys were investigated. </LI> <LI> Mo-Si-B alloys with different volume fractions or sizes of intermetallic compounds were fabricated by powder metallurgy. </LI> <LI> The oxidation resistance of Mo-Si-B alloys was improved with an increasing volume fraction of intermetallic compounds. </LI> <LI> The A3-P specimen had excellent oxidation property compared with the A3 specimen due to formation of oxide layer quickly. </LI> </UL> </P>

P131 Nail abnormalities shown in atopic dermatitis

( Yong Won Choi ),( Jee Hee Son ),( Yong Se Cho ),( Yun Sun Byun ),( Bo Young Chung ),( Hye One Kim ),( Hee Jin Cho ),( Chun Wook Park ) 대한피부과학회 2016 대한피부과학회 학술발표대회집 Vol.68 No.2

<div style="display:none">fiogf49gjkf0d</div><div style="display:none">fiogf49gjkf0d</div><div style="display:none">fiogf49gjkf0d</div><div style="display:none">fiogf49gjkf0d</div><div style="display:none">fiogf49gjkf0d</div><div style="display:none">fiogf49gjkf0d</div><div style="display:none">fiogf49gjkf0d</div> Background: Nail dystrophy arises from various inflammatory dermatologic diseases. However, there has been no report on the prevalence of nail abnormality in atopic dermatitis (AD) and it’s relation with severity of the disease. Objectives: This study is conducted to determine the prevalence and types of nail abnormalities in AD and evaluate the relation between nail abnormalities and the severity of AD. Methods: AD patients who visited outpatient clinic were thoroughly examined for nail abnormalities. Demographic information was collected and eczema area and severity index (EASI) score for severity of AD was checked. For statistical analysis, the chi-square test for nominal variables and the student’s t-test for continuous variables were used. And relative frequency of risk factors was analyzed by logistic regression using backward model Results: Total 235 atopic dermatitis patients aged 2 to 19 were investigated. Average age was 7.41 ± 5.00. There were 24 patients had nail abnormalities. The average EASI score of total patients was 9.81 ± 8.75. There was no statistically significant difference of total EASI score and development of nail abnormalities (p = 0.236). But EASI score confined to lower extremities showed relation to the prevalence of toe nail dystrophy (Odds ratio, 1.115; 95% confidence interval, 1.01 . 1.32; p=0.03) Conclusion: Nail abnormalities in AD can be caused by eczematous change in nail matrix, and EASI score confined to lower limb is associated with toe nail change.

Immunologic Changes After Treatment with Thymopentin in Atopic Dermatitis

Lee, Dong-Won,Park, Chun-Wook,byun, Dae-Gyoo,Kim, Chung-Won Catholic Medical Center 1991 Bulletin of the Clinical Research Institute Vol.19 No.1

Synchronous Occurrence of Papillary Thyroid Carcinoma and Mucosa-Associated Lymphoid Tissue Lymphoma: a Single Case Report

Jun Suk Byun,Hye Yoon Lee,Ki Won Chun,윤대성 대한갑상선학회 2016 International Journal of Thyroidology Vol.9 No.2

Papillary thyroid carcinoma (PTC) is a common lesion, accounting for 70-80% of all thyroid cancers, whereas mucosa-associated lymphoid tissue (MALT) lymphoma of thyroid gland is rare. A simultaneous occurrence of both malignancies is extremely rare. 57 years old Korean woman diagnosed with Hashimoto’s thyroiditis at left lobe of thyroid gland where atypical cells of undetermined significance at right lobe. Later, left lobe was confirmed with malignant lymphoma during series of fine-needle aspiration biopsy. Right lobe was interpreted as malignant lesions, such as papillary thyroid carcinoma based on ultrasonography images and previous biopsy results. Total thyroidectomy was performed. Pathology reported papillary thyroid carcinoma at right lobe and MALT lymphoma at left lobe. There were no post-operative complications and no recurrence yet reported. Since an association between Hashimoto’s thyroiditis and development of MALT lymphoma has been reported previously, a history of Hashimoto thyroiditis should be suspected MALT lymphoma.

Renal outcomes and clinical course of nondiabetic renal diseases in patients with type 2 diabetes

( Ja Min Byun ),( Cheol Hyun Lee ),( Sul Ra Lee ),( Ju Young Moon ),( Sang Ho Lee ),( Tae Won Lee ),( Chun Gyoo Ihm ),( Kyung Hwan Jeong ) 대한내과학회 2013 The Korean Journal of Internal Medicine Vol.28 No.5

Background/Aims: In several recent studies, renal biopsies in patients with type 2 diabetes and renal disease have revealed a heterogeneous group of disease entities. Our aim was to study the prognosis and clinical course of nondiabetic renal disease (NDRD) and to determine risk factors for NDRD in patients with type 2 diabetes. Methods: Renal biopsy reports of 110 patients with type 2 diabetes who were seen at Kyung Hee University Medical Center and Kyung Hee University Hospital at Gangdong, Seoul, Korea between January 2000 and December 2011 were retrospectively analyzed. Results: Of 110 patients with type 2 diabetes, 41 (37.3%) had diabetic nephropathy (DN), 59 (53.6%) had NDRD, and 10 (9.1%) had NDRD superimposed on DN. Immunoglobulin A nephropathy (43.5%) was the most common NDRD. Patients with NDRD had a shorter duration of diabetes, lower frequency of diabetic retinopathy, and better renal outcomes, which might have resulted from the use of aggressive disease-specific treatments such as steroids and immunosuppressants in patients with NDRD. Conclusions: Compared with DN, NDRD was associated with better renal outcomes in patients with type 2 diabetes, as evidenced by a higher cumulative renal survival rate and lower rate of end-stage renal disease (ESRD). Shorter duration of diabetes and absence of retinopathy were independent predictors of NDRD in patients with type 2 diabetes and renal involvement. Renal biopsy is recommended for patients with type 2 diabetes and risk factors for NDRD, to obtain an accurate diagnosis, prompt initiation of disease-specific treatment, and ultimately better renal outcomes with the avoidance of ESRD.