B 첨가 고탄소강의 흑연화에 미치는 냉간압연의 영향

박영구,우기도,이창희,류재화,나종필 한국열처리공학회 1999 熱處理工學會誌 Vol.12 No.2

The graphitization is affected by the addition of small amount of the elements(such as Si, Al, Ni, B, Cr and Mn etc.) and the pre-treatment(such as cold rolling). Boron is well known element to accelerate the graphitization of cementite in high carbon steels. Also, cold rolling is known to accelerate the graphitization. But the graphitization nucleation mechanism by cold rolling is few reported. Therefore the effect of cold rolling in Fe-0.5%C-1.0%Si-0.47%Mn-0.005%B steel on the graphitization is investigated quantitatively using hardness test, optical microscope and scanning electron microscope, neutron induced microscopic radiography. The nucleation of graphite in cold-rolled Fe-0.5%C-1.0%Si-0.47%Mn-0.005%B steel is formed at void which is formed at pearlite/pearlite boundary by cold rolling. But the effect of cold rolling on graphitization in boron addition steel is more effective than that of no boron addition steel due to segregation of BN at void in boron addition steel.

사료내 아미노산비가 흰쥐의 성장 , 도체성분 , 조직 유리아미노산 농도 및 뇨내 질소배설량에 미치는 영향

신종서,라창식,김창혁,김병완,송영한 한국영양사료학회 1999 韓國營養飼料學會誌 Vol.23 No.4

본 논문에서는 아미노산 혼합사료를 이용하여 사료내 질소 수준을 1.6N%로 일정하게 조절한 후 ET%의 단계적 변화(30, 50, 70ET%)가 휜쥐의 성장, 체성분, 혈중요소태 질소, 조직내 유리아미노산 농도 및 뇨중 질소량 변화에 미치는 영향을 검토하였다. 그 결과는 다음과 같이 요약되었다. 1. 증체량은 30ET%구에서 유의적으로 낮게(P<0.05) 나타났으나 사료섭취량은 50ET%구에서 유의적으로 높게 나타났으며(P<0.05), 증체량과 사료섭취량간에는 높은 상관이 인정되었다. 2. 도체 및 간장의 성분은 사료내 ET%의 변화에 의한 영향이 없는 것으로 나타났다. 3. 혈중 유리아미노산의 농도는 사료내 ET%의 변화에 민감하게 반응하였으며 특히 threonine 농도는 30ET%구에 비하여 70ET%구가 약 35배 정도로 유의적으로 높게 나타났다(P<0.05). 또한 총 필수아미노산의 농도는 사료내 ET%의 증가에 따라 유의적으로 증가하였으나 비필수아미노산 농도는 유의적으로 감소하였다(P<0.05). 간장 및 근육내 총필수아미노산과 비필수아미노산의 농도도 혈중 아미노산의 농도 변화와 비슷한 경향을 보였다. 4. 사료내 ET%에 따른 질소 배설량은 저 ET%구에 비하여 고 ET%구에서 높게 나타났으며 사육초기 보다 사육후기에 높은 질소 배설량을 보였다. 이와 같은 결과로 미루어 사료내 아미노산 조성은 중체량과 사료섭취량에 영향을 미칠 뿐만 아니라 조직내 아미노산 농도 및 질소 배설량에도 영향을 주기 때문에 정제 아미노산을 사료에 첨가할 때에는 비필수아미노산의 함량도 고려함으로서 효율적으로 사료의 이용성을 중진시키는 방향을 모색하는 것이 바람직 할 것으로 사료된다. The objective of this study was to investigate the effect of ET(essential amino acid/total amino acid) ratio variations (30, 50, 70 ET%) in the feeds on growth, body composition, blood urinary nitrogen, concentration of free amino acids in tissues and urinary nitrogen of rats. The nitrogen level in feed was constantly maintained at 1.6% with a purified amino acid, despite the difference in ET ratios. The results obtained are summarized as follows; 1. Body weight gain and feed intake was significantly lower and higher in 30 and 50 ET% than in other groups, respectively(P<0.05), and body weight gain was highly correlated with feed intake. 2. No ET% ratio effects on composition of carcass and liver were observed. 3. The concentration of plasma free amino acids varied with ET% ratios in the feeds, especially the concentration of threonine in 70 ET% was 35 times higher than that in 30 ET%. The concentration of total essential amino acids was significantly elevated by increasing ET% ratios in the feeds. In liver and muscle, the patterns of total essential amino acids and nonessential amino acids were similar to that of plasma amino acids. 4. Urinary nitrogen concentration increased with higher ratios of ET% in the feeds, and was higher in early growth stage than in late growth stage. These results indicate that the amino acid composition in the feeds influence the concentration of amino acids in tissue and urinary nitrogen as well as body weight and feed intake.

과공정 Al-Si 합금의 분무성형-압출에 따른 미세조직 변화

라형용,이호인,김상균,석현광,이재철,신돈수 대한금속재료학회(대한금속학회) 1998 대한금속·재료학회지 Vol.36 No.10

Microstructural evolutions of both Si particles and matrix grains of hypereutectic Al-Si alloy were investigated by calculating temperature profiles within the preform during spray forming. Based on calculations, the cooling rates were observed to be relatively higher both at the bottom and the top than the inner regions of the preform along the rotation axis of rod. Such trends in temperatures resulted in size variations of Si particles within the preform. The size of Si particles varies from 3㎛ to 13.5㎛ with distance from the surface to the inner of the preform along the rotation axis of rod. Larger Si particles observed from the inner regions of the preform were found to be poly-crystals having irregular surface boundaries. However, such Si particles were fractured after extrusion, indicating a possibile means for fabricating hypereutectic Al-Si alloys with fine Si particles. In addition, the methodology for predicting the matrix grain size in the presence of small Si particles was also demonstrated.

7075 Al 합금/SiCP 복합재료의 마멸특성 (1) : 상온 및 고온 마멸거동 Wear behaviour at room and elevated temperature

라형용,오창선,이영근 대한금속재료학회(대한금속학회) 1999 대한금속·재료학회지 Vol.37 No.2

Wear characteristics of 7075 Al/SiC_p composites fabricated by spray forming and extrusion process are studied. This study shows a wear transition from mild to severe wear as a function of applied load, sliding velocity and friction temperature with wear mapping approach. 7075 Al/SiC_p composites exhibit the transition from mild to severe wear when a load, sliding velocity or temperature reaches a critical value respectively. In mild wear regime; wear rate increases with increasing applied load. But wear rate decreases with increasing sliding velocity. At constant load and velocity in mild wear conditions, wear rate decreases with increasing friction temperature. The reasons are that the worn surface of disk was covered with much more iron oxides at elevated temperatures than at room temperature which played a role as solid lubricant. But in severe wean regime, this oxide layer is not stable and fractured, leading to increase wear rate and friction coefficient. Wear transition map of 7075 Al/SiC_p composites is constructed on applied load and sliding velocity axes with elevated temperatures. Severe wear regime is enlarged with increasing temperature on the wear transition map and wear transition conditions move to lower load and velocity at elevated temperatures than at room temperature. Therefore safe operating range of aluminum metal matrix composite parts is reduced at elevated temperatures.

페르시아어 ra 연구 : 격 표지와 주제화 표지로서의 역할을 중심으로

곽새라 ( Sae Ra Kwak ) 한국외국어대학교 중동연구소 2010 중동연구 Vol.29 No.2

This paper is to show how Persian "ra" functions in sentences both in grammatical Level and pragmatical level. In Persian traditional grammar, and even in the recent grammar books, "ra" has been introduced as a direct object marker, later as a definite direct object marker. However, several linguistic data show that this element can go with Persian indefinite marker "ye(k)" and "-i", which is the counter example of a definite direct object marker. We witness that Persian "ra" follows nouns or pronouns which are specific. All nouns which are definite are specific. Moreover, for indefinite nouns, if the nouns are only familiar to speakers, not to hearers, the nouns are specific. In sum, ra" can occur following specific direct objects. Another function of "ra" is its pragmatical function, which is topicalization marker. Topicalization is the strategy which expresses given information. Again, this topicalization also implies specificity. However, I argue that even though both functions imply one coommon characteristic, we cannot see "ra" in both cases as a functional marker, which is a specific marker. The facts that "ra" cannot follow subject position and this element is not a necessary condition for topicalization proves the argument. To sum up, Persian "ra" has two functions - one as a specific object marker, and the other as a topicalization marker, and thess two functions cannot be considered as one marker, such as specificity marker.

Retinoic acid induces expression of Ig germ line α transcript, an IgA isotype switching indicative, through retinoic acid receptor

Mi-Hee Park,박석래,Mi-Ra Lee,Young-Ha Kim,Pyeung-Hyeun Kim 한국유전학회 2011 Genes & Genomics Vol.33 No.1

Retinoic acid (RA) is considered to possess an activity of IgA isotype switching. Thus far, TGF-β1 is known to be the most powerful IgA isotype switch factor. To elucidate the molecular mechanisms underlying the Ig germ line (GL) α transcriptional regulation by RA, we constructed three different sizes of mouse GLα promoter reporters; short-GLα(-130/+14), middle-GLα(-448/+72) and long-GLα(-3028/+72). Based on luciferase assay, RA increased the activity of all three GLα promoter reporters by approximately 2-fold and the effect was further enhanced by TGF-β1. Overexpression of Smad3/4 increased TGF-β1-induced GLα promoter activities but had no effect on RA-induced GLα promoter activities. In order to analyze the characteristics of the RA-inducible GLα promoter region,we also constructed two mutant reporters: Smad3 binding elements (SBEs)-substituted short-GLα (short-GLα mSBE)and Runx3 binding elements (RBEs)-substituted short-GLα(short-GLα mRBE) promoter reporters. Promoter activities of the two mutant reporters to RA were comparable to that of wild type reporter, while those of the two mutant reporters to TGF-β1 were markedly diminished as compared to that of WT short-GLα. Finally, RA-induced GLα transcription was virtually disappeared by LE540, an antagonist of RA receptor (RAR). Taken together, these results suggest that RA induces GLα transcription mainly through RAR pathway, where neither Smad3/4 nor Runx3 is involved.

류마티스관절염 환자의 인슐린 저항성 결정인자

이정욱 ( Joung Wook Lee ),박영은 ( Young Eun Park ),조미라 ( Mi Ra Cho ),백승훈 ( Seung Hoon Baek ),김근태 ( Geun Tae Kim ),이준희 ( Jun Hee Lee ),김성일 ( Sung Il Kim ) 대한류마티스학회 2009 대한류마티스학회지 Vol.16 No.2

Objective: Rheumatoid arthritis (RA) is associated with an increased cardiovascular events. These may be related to insulin resistance (IR). We evaluated status of IR and analyzed the relationship between IR and clinical and laboratory characteristics in patients with RA. Methods: We examined 52 RA patients (43 females) and 52 age and sex matched healthy controls. We measured Homeostasis model assessment (HOMA) IR, calculated according to fasting serum glucose and insulin. Results: In patients, age was 50.8±10.2 years old, disease duration was 42.1±30.9 months. In controls, HOMA IR was 0.62±0.30 and in patients, it was 1.28±0.50. This difference was highly significant (p<0.001). Patients with early RA (disease duration is less than 36 months) were 28, and established RA (more than 36 months) were 24. HOMA IR was significantly higher in patients with established RA (1.42±0.45) than those with early RA (1.16±0.45) (p=0.03), and significantly correlated with disease duration (r=0.36, p=0.01), BMI (r=0.36, p<0.001), total cumulative prednisolon dose (r=0.34, p=0.01). Disease duration and BMI were independent predictors for HOMA IR (p<0.01, p=0.03). Conclusion: In patients with RA, IR measured by HOMA IR was more significantly increased than that of healthy control and significantly correlated with disease duration, BMI, and total cumulative prednisolon dose; however, the determinants of HOMA IR in RA patients were disease duration and BMI.

Retinoic acid enhances lactoferrin-induced IgA responses by increasing betaglycan expression

Lee, Jeong-Min,Jang, Young-Saeng,Jin, Bo-Ra,Kim, Sun-Jin,Kim, Hyeon-Jin,Kwon, Bo-Eun,Ko, Hyun-Jeong,Yoon, Sung-il,Lee, Geun-Shik,Kim, Woan-Sub,Seo, Goo-Young,Kim, Pyeung-Hyeun CHINESE SOCIETY OF IMMUNOLOGY 2016 CELLULAR AND MOLECULAR IMMUNOLOGY Vol.13 No.6

<P>Lactoferrin (LF) and retinoic acid (RA) are enriched in colostrum, milk, and mucosal tissues. We recently showed that LF-induced IgA class switching through binding to betaglycan (transforming growth factor-beta receptor III, T beta RIII) and activation of canonical TGF-beta signaling. We investigated the combined effect of LF and RA on the overall IgA response. An increase in IgA production by LF was further augmented by RA. This combination effect was also evident in Ig germ-line alpha (GL alpha) transcription and GLa promoter activity, indicating that LF in cooperation with RA increased IgA isotype switching. We subsequently found that RA enhanced T beta RIII expression and that this increase contributed to LF-stimulated IgA production. In addition to the IgA response, LF and RA in combination also enhanced the expression of the gut-homing molecules C-C chemokine receptor 9 (CCR9) and alpha 4 beta 7 on B cells. Finally, peroral administration of LF and RA enhanced the frequency of CCR9(+)IgA(+) plasma cells in the lamina propria. Taken together, these results suggest that LF in cooperation with RA can contribute to the establishment of gut IgA responses.</P>

류마티스관절염과 만성 호산구성 폐렴에 동반된 호산구성 흉막삼출

지용관 ( Yong Gwan Jee ),라상호 ( Sang Ho Ra ),박유미 ( Yu Mi Park ),차재황 ( Jae Whang Cha ),강용석 ( Yong Seok Kang ),박정하 ( Jeong Ha Park ),강태영 ( Tae Young Kang ) 대한류마티스학회 2013 대한류마티스학회지 Vol.20 No.5

We describe a 48-year-old man with family history of rheumatoid arthritis (RA) affected by chronic eosinophilic pneumonia (CEP) with severe peripheral eosinophilia. CEP might develop as a complication of longstanding active RA. The patient with 5 months history of seropositive RA and chronic respiratory symptoms, alveolar and blood eosinophilia, peripheral pulmonary infiltrates and pleural effusion on chest imaging. The lung may be involved as an extraarticular manifestation of RA. However, CEP is not recognized as a typical lung manifestation of RA, and the two diseases rarely coexist. The effusion was an eosinophil predominant exudates and was characterized by low pH, and glucose level and high lactic dehydrogenase. The patient responded rapidly to combination of steroids and disease modifying anti-rheumatic drugs.

Poster Session : PS 0691 ; Rheumatology ; A Randomized, Double-Blind, Phase 3 Equivalence Trial Comparing the Etanercept Biosimilar, Hd203, to Reference Etanercept, in Combination with Methotrexate (MTX) in Korean Patients with Rheumatoid Arthritis (RA)

( Sang Cheol Bae ),( Jinseok Kim ),( Jung Yoon Choe ),( Won Park ),( So Ra Lee ),( Yong Ho Ahn ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Etanercept is a recombinant fusion protein that blocks TNF. HD203 is a biosimilar of etanercept with demonstrated comparability across pharmacokinetics, safety and tolerability. The objectives of this study were to evaluate equivalence in effi cacy and compare safety of HD203 with reference etanercept, in combination with MTX in patients with RA. (ClinicalTrials. gov NCT01270997). Methods: Korean patients (male or female aged =20 years) with active RA were randomized (1:1) to 25 mg HD203 or reference etanercept, administered subcutaneously twice weekly with MTX for 48 weeks. The primary endpoint was the proportion of patients achieving ACR20 at week 24. Secondary endpoints included ACRn, DAS28, andEULAR response at week 24 and 48, safety and immunogenicity. Results: In total, 294 patients were randomized: HD203, n=147; reference etanercept, n=147. The proportion of patients achieving ACR20 at week 24 was not signifi cantly different between HD203 and reference etanercept. Equivalent effi cacy was demonstrated within predefined margins. There were no significant differences between proportions achieving ACR20 at week 12 and 48. ACR50 and ACR70 displayed similar trends. There were no signifi cant differences between groups for ACRn, DAS28, and EULAR response. Safety set analysis (HD203, n=147; reference etanercept, n=146) revealed no signifi cant difference for treatment-emergent (all-causality) adverse events (AEs): HD203 76. 87% vs. reference etanercept 78. 08% (p=0. 8040). No significant differences between HD203 and reference etanercept were observed for adverse drug reactions, serious AEs, or discontinuations due to AEs. Few patients tested positive for anti-drug antibodies. Conclusions: The study met the primary endpoint of demonstrating equivalent effi cacy of HD203 compared to reference etanercept. HD203 was well tolerated, with a safety profi le comparable to reference etanercept in this population of patients with RA.