On the Strengthening Effects Affecting Tensile and Low Cycle Fatigue Properties of Low-Alloyed Seismic/Fire-Resistant Structural Steels

Jung‑Ho Sim,Tae‑Yeong Kim,Jun‑Yeon Kim,Chi‑Won Kim,Jun‑Ho Chung,Joonoh Moon,Chang‑Hoon Lee,Hyun‑Uk Hong 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.2

In the present study, low carbon ferritic and bainitic steels with different contents of Mo, Ti, and Nb were designed for bothseismic and fire-resistant applications. The microstructure of steels containing 0.3 wt% Mo–0.02 wt% Nb (‘A’ hereinafter)was mainly composed of bainite. By contrast, the microstructure of steels with 0.2 wt% Mo–0.13 wt% Ti (‘B’ hereinafter)consisted of ferrite with a high density of nano-sized (Ti,Mo)-rich MX precipitates. The results showed that the bainiticmicrostructure (‘A’ steel) was quite favorable to high-temperature strength and thermal stability. The yield strength of ‘A’ steelat both room and 600 °C temperatures increased consistently with increasing thermal exposure time (600 °C/200–1000 h),since the precipitation of NbC particles occurred while maintaining bainitic ferrite platelets with a high density of dislocationsduring exposure. In the ‘B’ steel, the formation of nano-sized (Ti,Mo)-rich MX particles was effective to impededislocation movement, leading to excellent plasticity (lower yield ratio) at room temperature. However, their contributionto precipitation hardening was not so much at 600 °C, as compared to the bainitic strengthening. During low cycle fatiguetests at room temperature, the main different feature between the two steels is that the ‘A’ steel showed cyclic softeningwhile cyclic hardening was evident in the ‘B’ steel. The bainitic microstructure showed a better fatigue life due to increasedductility manifested by cyclic softening, by which dislocation cell was developed.

정신분열병과 Glutathione S-Transferase M1유전자 다형성

배치운,조자현,김연주,김태석,김정진,이창욱,이수정,전태연,이철,백인호 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.5

Objectives : This study aimed to test the possible association between Glutathione S-Transferase Ml gene (GSTMl) variants and schizophrenia. Methods : One hundred and eleven inpatients with schizophrenia and 130 healthy controls were recruited. Genotyping was performed by polymerase chain reaction-based method. Results : The GSTMl null genotype was significantly more frequent in patients with schizophrenia than in controls (p=0.014, odd ratio=1.93, 95% confidence interva1=1.115-3.351), while GSTMl genotype vahants were not associated with either tardive dyskinesia (TD) or total Abnormal Involuntary Movement Scale (AIMS) scores. Conclusion : The present study suggests that the GSTMl polymorphism may confer susceptibility to the development of schizophrenia but not to TD, at least in Korean population.

단백질-다당질 복합겔의 용해도 및 전기영동 특성에 미치는 몇가지 첨가제의 영향

정경임,이동선,하정옥 경남대학교 신소재연구소 1996 論文集 Vol.6 No.-

본 연구에서는 닭고기에서 조제한 근원섬유 단백질(MP)과 MP와 유청 단백질 분리물(WPI)의 혼합물, MP와 대두 단백질 분리물(SPI)의 혼합물 등의 3가지 종류의 단백질과 다당질로서 methyl cellulose, sodium alginate, xanthan gum을 택하여 단백질-다당질의 복합겔을 만들고 NaCl, NaSCN, propylene glycol, 2-mercaptoethanol들의 처리에 의해 단백질-다당질간의 상호작용에 기인하는 겔의 용해도 및 전기영동에 의한 겔 용해에 따른 상징액의 변화 등을 조사함으로써 단백질 식품의 기능적 특성에 미치는 영향을 고찰해 보았다. 겔 용해도는 대체로 모든 다당질에 대해 낮은 용해도를 나타냈으나 세 가지 단백질 시료에 대해 2-mercaptoethanol 처리시 가장 많은 단백질이 용해되어 나온 것으로 나타났다. 2-mercaptoethanol은 단백질간 상호작용, 즉 겔 망상구조를 이루는 sdisulfide 결합을 크게 방해함으로써 가장 높은 용해도를 나타낸 것으로 생각된다. 모든 시료에 대해 NaCl과 NaSCN 용액에 대해서는 아주 낮은 용해도를 보였는데, 이것은 NaCl과 NaSCN은 저 농도일 경우, 단백질 구조를 안정화함으로써 단백질간의 상호작용이 크게 증가되어 용해되는 단백질의 양이 극히 낮아진 것으로 보인다. Xanthan gum은 가장 겔 용해도가 낮았고, 특히 MP와 xanthan gum으로 이루어진 겔에서는 아주 극소량의 단백질이 용해되었다. Methyl cellulose 겔의 경우, 모든 용액에서 단백질이 거의 용해되어 나오지 않았다. 그러나, 1% WPI를 혼합한 경우 역시 겔 용해도가 낮았으며 여전히 MP의 단백질 성분은 용해되어 나오지 않았고 WPI의 주요성분인 α-lactalbumin과 β-latcoblobulin이 많이 용해되어 나왔다. 1% SPI을 혼합한 겔은 셀 용해도도 여전히 낮았으며 전기영동 결과에서도 SPI 성분의 단백질 band가 아주 미약하게 나타났다. 이것으로 보아 WPI는 다소 불안정한 겔을 형성하여 용해도를 증가 시키고 반대로 SPI는 겔을 안정화하여 단백질 용해도를 감소시켰으리라 짐작된다. Sodium alginate 겔의 경우, 단백질 용해도는 아주 낮았으나 3 가지 단백질 시료 모두 용해되어 나왔다. 이것으로 sodium alginate는 단백질과 다소 불안정한 겔을 형성한다는 것을 알 수 있다. X무소무 gum 겔에서도 역시 MP와 MP+SPI 혼합겔은 아주 낮은 겔 용해도를 뒷받침하듯 단백질 band를 거의 확인할 수 없었으나 WPI를 혼합한 겔만이 WPI의 주요성분인 α-lactalbumin과 β-latcoblobulin 성분이 용해되어 나왔다. 즉, methyl cellulose와 xsanthan gum 겔의 경우, 근원섬유 단백질은 거의 용해되어 나오지 않았고 유청 단백질 분리물의 성분이 많이 용해되어 나왔으며 대두 단백질 분리물은 단백질과의 결합력이 커 용해된 단백질 성분이 아주 미약했다. Sodium alginate 겔의 경우 모든 단백질 성분이 용해되어 나온 것으로 보아 sodium alginate는 단백질과 결합하여 불안정한 겔을 형성하는 것으로 나타났다. Interactions between polysaccharides and proteins occur widely in biological system. Their interaction in food system often plays a role in determining the functional properties of these systems. The effects of various reagents such as NaCl. NaSCN. propylene glycol and 2-mercaptoethanol on the gel solubility of heat-induced gels of protein and polysaccharide were studied. Protein samples were myofibrillar proteins(MP) extracted from chicken breast muscle and the combinations of MP plus whey protein isolate(WP1) and MP plus soybean protein isolate(SP1). As polysaccharides in preparation of gels, methyl cellulose, sodium alginate and xanthan gum were used. Protein- polysaccharide composite gels were formed by heating at 80 C for 30 min. In the effects of reagents on gel solubility, 2-mercaptoethanol had higher solubility than other reagents. indicating that 2-mercaptoethanol cleaved disulfide bonds in the protein-polysaccharide composite gels. In order to indicate the composition of protein solubilized from gels by the treatment of various reagents such as 0.1 M NaC1. 0.1 M NaSCN. 20% propylene glycol, 0.04 M 2-mercaptoethanol, the solubilized proteins were analyzed by SDS-PAGE. In methyl cellulose and xanthan gum gels. less protein was solubilized by reagents, but MP gels with WPI was solubilized more abundantly than SPI.

수입각증후군에 의한 급성 복증 1례

정은욱,지삼룡,이영태,박지훈,김동기,제인수,채두근,박성재,박은택,이연재,이상혁,설상영,정정명 白中央醫療院 2005 仁濟醫學 Vol.26 No.1

Afferent loop syndrome is an uncommon complication of a gastrectomy and Billroth Ⅱ reconstruction. It may cause symtoms at any time from the first postoperative day to many years after the gastrectomy. Afferent loop syndrome is characterized by abdominal pain, vomiting and elevation of serum amylase. Thus, it is difficult to differentiate afferent loop syndrome from other cause of acute pancreatitis. However, the history of gastrectomy can be an important clue for diagnosing afferent loop syndrome. We experienced one case of chronic afferent loop syndrome with acute pancreatitis. After appropriate management, the abdominal pain disappeared and serum amylase level decreased. We report this case with a review of relevant literatures.

酸棗仁이 CT105에 의한 신경세포 상해 및 白鼠의 기억에 미치는 영향

정정욱,박창국,박치상,이소연,윤현덕,신오철 대한본초학회 2005 大韓本草學會誌 Vol.20 No.1

Objective: This study was designed to research whether demonstrate neuroprotective and memory enhancing effects of Z1BU, suggesting its beneficial actions for the treatment of AD. Methods: The present study investigated effects of the dichloromethane extract of Semen Zizyphi Spinosae(ZIBU) on neurotoxicity and reactive oxygen species(ROS) and nitric oxide(NO) formation in PC 12 cell line overexpressed with carboxyl-terminal 105 amino acid peptide fragment of amyloid precursor protein(CT105). In addition, the present study evaluated its radical scavenging activity and effects on acetylcholinesterase(AChE) activity. Furthermore, effects on neuronal loss in CAl area and cognitive deficits induced by scopolamine treatment were also evaluated in rats. Result: we found in this study that ZIBU significantly inhibited apoptotic neuronal death induced by CT105 overexpression in PC12 cells, with the IC_(50) value of 23 ㎍/ml. Based on phase-contrast and fluorescence microscopic examinations, ZIBU reversed morphological changes of CT105-expressed PC-12 cells. It was also found that Z1BU significantly induced neurite outgrowth and inhibited formation of ROS and NO.Z1BU scavenged DPPH radicals and inhibited AChE activity. Furthermore, it attenuated memory impairment induced by the injection of scopolamine in rats, based on passive avoidance test. Crystal violet staining of rat brain slices exhibited increase in the viability of pyramidal neurons in hippocampal CAI area. Conclusion: these results demonstrate neuroprotective and memory enhancing effects of ZIBU, suggesting its beneficial actions for the treatment of AD.

비스판 변이주인 Bacillus polyfermenticus KD21의 주요 생균제 특성

정민용,정황영,하정욱,백현동 慶南大學校 附設 基礎科學硏究所 2002 硏究論文集 Vol.16 No.-

Bacillus polyfermenticus SCD which is commonly called as Bispan strain are being used for functional foods using the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine in both humans and animals. B. polyfermenticus KD21 was obtained for higher sporulation through the NTG mutagenesis. The cells of B. polyfermenticus KD21 was treated for 24 h in artificial bile after incubation for 2 h in artificial gastric juice and final number of the strain was reached to around 10^8 CFU/㎖. In test of API ZYM kit, β-glucuronidase or β-glucosidase were not produced by B. polyfermenticus KD21. B. polyfermenticus KD21 was resistant to antibiotics such as nisin, tetracyclin, streptomycin, and rifamycin. B. polyfermenticus KD21 was shown to inhibit the growth of Listeria monocytogenes ATCC 19111 completely within 24 h of incubation, which indicates its bactericidal nature.

교원의 노동조합 설립 및 운영 등에 관한 법률과 교원노조 활동에 대한 교원의 인식 연구

정회욱,송정우 木浦大學校 敎育硏究所 2004 교육연구 Vol.16/17 No.-

이 연구는 교원의 노동조합 설립 및 운영 등에 관한 법률과 교원노조 활동에 대한 교원의 인식 연구이다. 본 연구에 따르면, 다수의 교사들은 다음과 같이 인식하고 있다. 교원들의 쟁의행위 허용 주장은 「정상적인 업무를 저해하지 않는」 집단행동 허용을 원하고 있기 때문에 법리적으로는 노조법상 쟁의행위가 아닌 국가공무원법 또는 교육공무원법상 단체행동 허용을 의미한다. 교원노조법에 단체 교섭의 대상에 대한 명문의 규정이 없으므로 인사제도, 교육정책·교육과정에 관한 사항이라고 하더라도 교원의 고용과 밀접불가분의 관계가 있는 사항은 단체교섭의 대상이 되어야 한다. 교원노조의 단체협약은 조합원에게만 적용되는 것이 협약의 본래의 성격이나 사용자가 형평성의 원리에 입각하여 임의로 비조합원에게도 적용하기 때문에 교원노조는 단체협약 체결에서 전체교사의 의견을 반드시 수렴하여야 한다. 그리고 교원노조의 가장 중요한 과제는 이념투쟁이 아니라 단체교섭을 통한 현장교육문제의 해결이라는 의견이 지배적이었다. This study has analysed the teacher's understanding of the 'Law for the Teacher's Union, activities and collective bargaining and showed their claims for the desirable activities from Korean Teachers and Educational Workers' Union. This study proposed studying assignments to achieve this kind of studying purpose as follows. First, how do the teachers think of 'Law for the Teacher's Union' and what's its problem? Second, how do the teachers think of teachers' union system and what's its improvement? The sample of this study was 342 teachers who work at an elementary, middle and high schools in Tae-baek City, Kang-won Province. Of 342 questionnaires distributed, 308 were returned (response rate was 90.1%), but of 308 questionnaires unreliable 18 were exempt from the application of these samples. This questionnaire data were composed of 32 questions. This statistical methods for data processing were frequencies analysis and Chi-sqare tests by SPSS to find a correlation between individual variation and each questions. This study was analysed as p<.05 within a significant level The conclusion that resulted from the data analysis were as follow. First, the admission of teachers' union of school unit should be decided through full discussion and profound debate, but in reality, the establishment of school unit is impossible because of conflict problems among the teachers' position Second, the permission of both a collective action and political activities of Korean Teachers and Educational Workers' Union also has to be profoundly discussed because it can be different from teachers' position, their career, or a member of union whether or not. If it is permissible, its permission should only be approved within its limit without a bad influence on study right and teaching-learning, therefore such results are undesirable. Third, according to the law now in force, agenda of collective bargaining is subjected to restriction in elevation of economical and social position of teacher. In spite of being an educational policy now, however, it is necessary for the teachers to expand that as the agenda of collective bargaining as to employment. The dual collective bargaining system of KTEU(Korean Teachers and Educational Workers' Union) and KFTA(Korean Federation of Teachers' Associations) can have an effect of checks and balances. Fourth, a member of union has to act within the limit of the law and manager should reciprocally endeavor to form democratical administration because a conflict between manager and a member of union in school causes a schism between two parts. Finally, collective agreement between the superintendent of education and teachers' union should be entered into an agreement through procedures of collecting sufficient public opinion. the problem which confronts teachers' union should try to find a solution to the problem without being split in teachers' profession. Moreover teachers' union should be in search of a better solution. It is necessary for pressure group, and to act through playing careful attention to the tends of public opinion and policy-making.

산후에 발병한 특발성 부갑상선 기능저하증 I 예

김정인,김상용,신병철,김경남,서영욱,이범주,김진화,배학연 朝鮮大學校 附設 醫學硏究所 2002 The Medical Journal of Chosun University Vol.27 No.2

Hypoparathyroidism is usually the result of an inadvertent surgical removal of all the parathyroid glands, In some instances, not all the tissues are removed, but the remainder undergoes vascular supply compromise secondary to the fibrotic changes in the neck after surgery, Previously, the surgery for hyperthyroidism was the most frequent cause of acquired hypoparathyroidism. Idiopathic hypoparathyroidism is a relatively rare disease that is characterized by hypocalcemia and hyperphosphatemia due to a parathyroid hormone deficiency of an unknown cause, It usually develops at a young age, and shows various clinical symptoms and signs accompanied with hypocalcemia. In addition, it is rarely associated with polyglandular autoimmune syndrome during the follow-up. Hypocalcemia and idiopathic hypoparathyroidism associated with labor and lactation are rarely reported condition previously. We here describe a case of a woman in whom the symptomatic severe hypocalcemia appeared after her delivery. We reviewed all the previously reported cases and suggest a possible physiological explanation for the association between pregnancy, lactation, and the appearance of symptomatic hypocalcemia.

주둥치, Leiognathus nuchalis(Temminck et Schlegel)의 仔稚魚期의 形態

明正求,金容億 釜山水産大學校 1984 釜山水産大學 硏究報告 Vol.24 No.1

南海昌善海峽에서 採集된 주둥치의 仔稚魚期에 있어서의 成長에 따른 外部形態, 體形 및 內部形態의 變化를 調査한 결과는 다음과 같다. 1. 주둥치는 後期仔魚期를 경과하는 동안 體長 4.1∼6.0㎜ 範圍에서 급격한 形態變化를 나타내고 體長 12. 3㎜에서 稚魚期에 도달한다. 2. 變態期인 體長 6.0㎜가지는 體長에 비해 꼬리부분이 가장 빨리 成長하며, 그 이후는 體高가 가장 빠른 속도로 成長하고 꼬리 부분은 가장 成長이 늦어진다. 3. 대부분의 骨格은 6.0㎜까지 骨化되며, 지느러미줄기는 體長12.3㎜에서 정수에 달한다. 4. 턱니는 거의 일정하게 증가하나 咽頭齒는 體長 6.0㎜경에 급격히 증가한다. 5. 消化管은 처음에 한번 廻轉되어 있으나, 體長6.0㎜부터 곧창자 앞부분이 굽어지기 시작하여, 體長 25.2㎜에는 한번 廻轉되고 두 번 銳角形으로 굽어진 形態가 된다. The morphological changes with growth Leiognathus nuchalis were investigated. Two hundred twenty one individuals were utilized for this study and its body length varied from 1.5 to 25.2㎜. These specimens were collected in changson channel, Namhae during the summer season (June-July) in 1982 and 1983. The metamorphosis was recognized in the post larval stage between ca. 4.1㎜ and 6.0㎜ in body length. Up to metamorphosis, the tail developed faster than any other body part. However, after metamorphosis the body height developed the fastest and the tail the slowest. Metamorphosis brought about not only ossification of many elements, but also exchange of larval features to adult ones. The latter happened typically to jaw bones and preopercles. The unpaired fins developed earlier than the paired fins. the dorsal and anal fin rays were at first formed when the body length was ca. 4.1㎜, and as it attained ca. 5.8㎜, the number of the fin rays reached of the adult's ones. In The unpaired fins, the development of the caudal fin preceded that of the dorsal and anal fins. Each fin formation was completed when the body length was ca. 12.3㎜, and this post larva entered juvenile stage. Upper jaw teeth were formed only on the premaxillary. While the numbers of teeth on the jaw increased almost constantly, those on the upper and lower pharyngeal bones increased in proportion to body length with a more or less conspicuous leap when the ./body length was ca. 6.0㎜. The alimentary canal of L.nuchalis had a single winding form until the body length was 6.0㎜, and the thereafter, it became to develop a sharp bend followed by a outward second bend.

정신분열병 환자에서 얼굴 영상의 작동기억 장애 : 기능자기공명영상연구

이창욱,김태석,주라형,박주미,박여진,김종진,전신수,배치운,김정진,이수정,이철,백인호 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.2

Objectives : Impaired processing of facial information is one of the broad ranges of cognitive deficits seen in patients with Schi-zophrenia. We aimed to elucidate the differences in brain activities involved in the process of facial working memory between schizophrenic patients and healthy comparison subjects. Methods : Twelve patients with schizophrenia were recruited along with twelve demographically matched healthy volunteers as a comparison group. Functional magnetic resonance imaging (fMRI) was used to assess cortical activities during the Perfor-mance of a 2-back working memory paradigm using images of neutral faces as mnemonic content. Rcsults : The patient group performed the tasks with reduced accuracy. Group analysis revealed that the left fusiform gyrus, the right superior frontal gyrus, the bilateral middle frontal gyri/insula, the left middle temporal gyrus, the precuneus, the quadrangular lobules and the vermis of cerebellum showed decreased cortical activities in the patient group. On the other hand, an increased level of activation in the lateral prefrontal cortex and the pahetal lobule was observed from the patient group, all in the right hemisphere. Conulusion : A decreased level of activity in the left fusiform gyrus among the patient group implicates inefficient processing of facial information. An increased level of activation in prefrontal and parietal neural networks from the patient group confirms earlier findings on the impaired working memory of patients with schizophrenia.