Influence of Al2O3 Content and Cooling Rate on Crystallization in Fe2O3–CaO–SiO2–Al2O3 Systems

Tae Jun Park,Joon Sung Choi,Dong Joon Min 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.9

The behavior of silico-ferrite of calcium and aluminum (SFCA) phases and the influence of sintered ore quality were investigatedusing a confocal laser scanning microscope to understand how the Al2O3content of iron ore affects the sintered orestructure and the crystallization behavior of SFCA in a Fe2O3–CaO–Al2O3–SiO2 pseudo-quaternary system. The experimentalresults were used to inform simulations of the heterogeneous dynamic behavior in response to the rapid temperature changesand various chemical compositions typically encountered in actual sintering processes. Increasing the Al2O3content in theFe2O3–CaO–Al2O3–SiO2 pseudo-quaternary system led to the hematite content decreasing, which affects the reducibilityof the sintered ore. The correlation between the creation of SFCA and the cooling effect associated with varying the Al2O3is discussed in detail.

단기간의 금연과 일회성 유산소 운동이 흡연자의 심혈관 반응에 미치는 영향

송준경(Jun Kyung·choi),최현민(Hyun Min Choi),김종경(Jong Kyung Kim),노호성(Ho Sung Nho) 한국사회체육학회 2012 한국사회체육학회지 Vol.0 No.48

The purpose of this study was to investigate cardiovascular responses to a bout of aerobic exercise and acute smoking cessation in smoker. nine collegiate male smoker who have been smoking(duration of smoking: 7.5 ± 0.9yrs; number of cigarettes per day: 15.5 ± 1.5) participated in this study. All subjects performed PEI to stimulate Group IV metaboreceptor at immediately after smoking, 24hours after smoking cessation and smoking after a bout of aerobic exercise. they were measured SBP, DBP, HR, SV, CO, TVC using by finometer(FMS co, Netherland). As a result, compared to immediately after smoking, SBP, DBP, and MAP were significantly decreased 24-hours after smoking cessation at rest and PEI(p<0.05). In addition, smoking after a bout of aerobic exercise caused by post-exercise hypotension indicated that SBP was significantly decreased compared to immediately after smoking(p<0.05). also, the changes in DBP and MAP at rest and handgrip exercise were significantly smaller compared to immediately after smoking(p<0.05). Thus, the results showed that smoking cessation during 24-hours and a bout of aerobic exercise relieve excess blood pressure response and enhanced arterial baroreflex in collegiate male smoker. It is concluded that caused exercise pressor reflex by stimulated Group IV may be effective to improve excess blood pressure responses.

The prediction of the tooth size in the mixed dentition for Korean

Moon, Sung-Hwan,Kim, Seong-Oh,Yu, Hyung-Seong,Choi, Byung-Jai,Choi, Hyung-Jun,Lee, Jae-Ho 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.2

이번 연구의 목적은 혼합치열기 아동에서 미맹출된 견치와 소구치의 크기를 예측하는데 있어서 한국인에 맞는 방정식을 만들기 위함이다. 미맹출 치아의 크기를 예측하는 것은 혼합치열기 교정 진단과 치료계획 수립에 있어서 매우 중요하다. 미맹출된 견치와 소구치 크기를 예측하는 방법은 몇가지가 있지만 그중에서도 가장 흔하게 쓰이는 것이 모이어의 예측표와 다나카와 존스턴의 방정식이 있다. 하지만 그것들은 백인을 위해서 제작된 것이고 치아 크기는 인종에 따라서 다르다고 알려져 있다. 이번 연구에서는 치아크기를 측정하여 하악 영구 절치의 크기 합과 견치 및 소구치의 크기 합 사이의 상관관계를 구하고 회귀방정식을 이용해서 한국인에 맞는 예측표를 만들었다. 연세대학교 치과대학에 재학중인 178명의 한국 학생(남 108명, 여 70명, 평균연령 21.63)을 대상으로 실험하였다. 영구치의 근원심 폭경을 석고모형상에서 calipers를 이용해서 측정하였다. 성별간의 치아 크기는 차이가 있었다(p<0.05). Correlation coefficient는 0.57에서 0.64의 범위였고, standard errors of the estimates 는 여성에서 0.6으로써 남성보다 우수하였다. r^(2)값은 0.27에서 0.41의 범위를 나타내었다. Estimating the size of unerupted teeth is an essential aspect of orthodontic diagnosis and treatment planning in the mixed dentition. Several methods were introduced and used for the prediction. The most common methods among these would be Moyers probability chart and Tanaka and Johnston equations. These are currently used widely, but they were developed for Caucasians. Because there are clear racial differences in teeth size, the objectives of this study were to produce correlation coefficients between the combined mesiodistal widths of the permanent mandibular incisors and those of the canines and premolars for each quadrant, and prediction tables with regression equations, specifically for Korean. 178 young adults (70 women, 108 men, mean age 21.63 years) were selected from the College of Dentistry, Yonsei University, Seoul, Korea. The mesiodistal crown diameters of the permanent teeth were measured with calipers. Significant sexual dimorphism was found in tooth sizes. The correlation coefficients between the total mesiodistal width of the mandibular permanent incisors and those of the maxillary and mandibular canines and premolars were found to be between 0.52 and 0.64. The standard error of the estimatation was better (0.60) for women and the r^(2) values ranged from 0.27 to 0.41 for both sexes, Prediction tables were prepared for Korean. This study showed larger canine and premolar diameters than Tanaka and Johnston's and Moyers' studies which might be due to the racial differences. Further investigations with a larger sample size will be needed for more representative data on the Korean population.

The effect of neuropeptides on secretion of Interleukin-8(IL-8)

Kim, Kyung-Jun,Park, Sang-Hyuk,Choi, Kyoung-Kyu,Park, Sang-Jin 大韓齒科保存學會 2006 Restorative Dentistry & Endodontics Vol.31 No.3

본 연구는 치수조직, 치은, 치주인대로부터 배양된 조직을 SP (Substance P)로 4시간, SP, CGRP (Calcitonin Gene-related Peptide), Tumor necrosis factor-α (TNF-α)로 8시간 자극 후 RNase Protection Assay를 시행하고, IL-8의 분비량을 측정해 다음 결과를 얻었다. 1. IL-8 mRNA는 모든세포에서 발현됐다. 2. IL-8 mRNA 발현은 SP (10^(-5)M)와 SP (10^(-8)M)로 4시간 자극 시 증가되지 않았다. 3. IL-8 mRNA 발현은 SP (10^(-4)M)와 CGRP (10^(-6)M)로 8시간 자극 시 증가되지 않았다. 4. TNF-α (2 ng/㎖) 자극 시, IL-8 mRNA 발현이 증가됐다. 5. 치은 세포를 CGRP (10^(-6)M)로 8시간 자극 시, IL-8 분비량이 증가했다 (p < 0.05). 6. 치주인대 세포를 SP (10^(-4)M)로 8시간 자극 시 IL-8 분비량이 증가했다 (p < 0.05). We investigated the secretion of Interleukin-8 (IL-8) from ginviva and periodontal ligament stimulated with Substance P (SP) and Calcitonin Gene-related Peptide (CGRP). Gingiva (GF), periodontal ligament (PDLF) and pulp (PF) tissues were collected from extracted instact 3rd molars. Cultured cells were stimulated with different concentrations of SP for 4 hrs, and stimulated with SP, CGRP and Tumor Necrosis Factor-α (TNF-α) for 8 hrs. Then RNase Protection Assay was carried out. ELISA was performed using supernatants of stimulated cells for quantitative analysis of IL-8. Results were assessed using supernatants of stimulated cells for quantitative analysis of IL-8. Results were assessed using student t-test with significance of P < 0.05. According to this study, the results were as follows: 1. IL-8 mRNA was detected in all type of cells studied (PF, GF and PDLF). 2. IL-8 mRNA expression was not increased after stimulating 4 hrs with SP (10^(-5)M) and SP (10^(-8)M) compared with Mock stimulation in all type of cells studied. 3. IL-8 mRNA expression was not increased after stimulating 8 hrs with SP (10^(-4)M) and CGRP (10^(-6)M) compared with Mock stimulation in all type of cells studied. 4. TNF-α (2 ng/㎖) increased the expression of IL-8 mRNA in all kind of cells studied. 5. The secretion of IL-8 from GF was increased 8 hrs after the stimulation with CGRP (10^(-6)M) (p < 0.05). 6. The secretion of IL-8 from PDLF was increased 8 hrs after the stimulation with SP (10^(-4)M) (p < 0.05). Calcitonin Gene-related Peptide (CGRP) increased Interleukin-8 (IL-8) which plays an important role in chemotaxis of neutrophil in Calcitonin Gene-related Peptide (CGRP) gingival tissue, whereas Substance P increased the secretion of IL-8 from periodontal ligament.

최씨 훅을 이용한 복강경 버찌씨 수술

김영혜 ( Young Hye Kim ),박준선 ( Jun Seon Park ),최상준 ( Sang Joon Choi ),송창훈 ( Chang Hoon Song ),한세준 ( Sei Jun Han ),정혁 ( Hyuk Jung ) 대한산부인과학회 2006 Obstetrics & Gynecology Science Vol.49 No.6

목적: 버찌씨 수술은 복압성 요실금 수술에 효과적인 수술로 여겨져 왔다. 요실금의 원인이 내인성 요도 괄약근의 결손소견 없이 요도의 과운동성으로 인한 경우 버찌씨 수술이 일반적으로 추천되어진다. 본 연구에서는 복강경 버찌씨 수술에서 최씨 훅의 유용성에 대해 알아보고자 하였다. 연구방법: 2000년 10월부터 2005년 3월까지 본원에서 복강경 버찌씨 수술을 시행받은 47명의 환자를 대상으로 하였다. 27명은 고전적 복강경 버찌씨 수술을 시행하였고 20명은 내골반 근막을 Cooper 인대를 부착하는데 유용한 본원에서 고안한 최씨 훅을 이용하여 복강경 버찌씨 수술을 시행하였다. 결과: 고전적 복강경 버찌씨 수술을 시행한 군과 최씨 훅을 이용한 복강경 버찌씨 수술을 시행한 군의 평균 나이, 분만력, 폐경률, BMI는 두 군간에 통계학적으로 유의한 차이를 보이지 않았다 (p>0.05). 수술 시간은 고전적 복강경 버찌씨 수술은 90.52±15.32분, 최씨 훅을 이용한 복강경 버찌씨 수술은 38.50±10.14분으로 최씨 훅을 이용한 경우 수술시간이 통계적으로 유의하게 짧았다 (p<0.05). 두 군간에 재발률 및 합병증 발생은 통계적 유의성을 보이지 않았다 (p>0.05). 결론: 본 연구에서 본원에서 고안한 최씨 훅을 이용하여 복강경 버찌씨 수술을 시행한 결과 수술 시간을 단축시킬 수 있었으며 수술 효과는 기존 방법과 동일하게 관찰되었다. 이에 최씨 훅은 복강경 버찌씨 수술에서 사용할 때 집도자의 봉합 과정을 단순화시켜 수술 시간을 단축시키므로 복강경 버찌씨 수술에 용이한 기구이다. Objective: Burch operation has been effective method for the treatment of stress incontinence. Burch operation is a well-accepted procedure for treating stress urinary incontinence secondary to urethral hypermobility without intrinsic sphincter deficiency and is the reference standard with which other procedures are compared. This study is to evaluate the effectiveness of the Choi`s hook in laparoscopic Burch operation. Methods: This study included 47 patients who had undergone laparoscopic Burch operation from October 2000 through March 2005. Of these 47 patients, 27 patients underwent traditional laparoscopic Burch operation (Group 1) and 20 patients underwent laparoscopic Burch operation with Choi`s Hook on anchoring the endopelvic fascia to the Cooper`s ligament (Group 2). Results: The mean age of patients of Group 1 was 55.6±9.37 years of age and that of Group 2 was 56.0±5.93 years of age. There is no difference in the mean age of patients (P>0.05). The mean operating time was 90.5±15.32 minutes for Group 1 and 38.5±10.14 minute for Group 2. The mean operating time was shorter in Group 2 than Group 1 (P<0.05). There was no difference in recurrence rate and complication rate between Group 1 and Group 2 (P>0.05). Conclusion: We performed laparoscopic Burch operation with the Choi`s Hook on anchoring the endopelvic fascia to the Cooper`s ligament. When we compared traditional laparoscopic Burch operation with laparoscopic Burch operation with Choi`s Hook, we could shorten the operation time using the Choi`s Hook.

실용음악 전공 학생들의 발성치료 전후 성대 및 음성 특성 비교

황연신,심미란,김철준,최용석,김상연,최찬호,선동일,Hwang, Yeon Shin,Shim, Mi Ran,Kim, Chul Jun,Choi, Yong Suk,Kim, Sang Yeon,Choi, Chan Ho,Sun, Dong Il 대한후두음성언어의학회 2016 대한후두음성언어의학회지 Vol.27 No.2

Background and Objectives : Many students major in applied music singing have various difficulties in phonation when they sing or perform. But the studies about this cause are lack. The purpose of this study is whether singing voice therapy based on vocal music is effective or not to applied music singing students that have difficulties in phonation. Materials and Methods : Singing voice therapy program had been done to 8 students major in applied music singing during 7 weeks. We did laryngeal stroboscope, perceptual, acoustic and aerodynamic examination before and after singing voice therapy to this students. And we studied post examination results have differences or improvements compared to pre examination results. Results : Four male students don't have effective improvement after singing voice therapy but they shows slight improvement in aerodynamic examination values compared to pre examination values. Four female students shows improvement in aerodynamic examination values and pitch range increasing. Above all, one student's vocal nodules disappeared after singing voice therapy. Conclusion : Singing voice therapy based on music singing is very effective to the students major in applied music singing. Above all, their curriculum in applied music singing should include phonation training based on music singing before training perform and technic practices.

배추의 형질전환용 선발항생제로서 Paromomycin의 이용

조미애,민성란,고석민,유장렬,이준행,최필선,Cho, Mi-Ae,Min, Sung-Ran,Ko, Suck-Min,Liu, Jang-Ryol,Lee, Jun-Haeng,Choi, Pil-Son 한국식물생명공학회 2006 식물생명공학회지 Vol.33 No.4

정상' 배추와 '서울' 배추의 배축절편을 선발마커로서 hygromycin 저항성유전자를 갖고 있는 pCAMBIA1301와 paromomycin저항성유전자를 갖고 있는 pPTN290으로 각각 형질 전환된 LBA4404 또는 EHA101균주와 공동배양한 후 선발배지에서 배양하면서 형질전환체를 선발하였다. 형질전환빈도는 사용된 항생제와 품종에 따라서 현저하게 차이가 있었으며, 특히 paromomycin은 hygromycin보다 효과적이었고 정상 배추는 서울배추보다 양호하였다. 가장 높은 형질전환빈도는 (0.70%) 100mg/L paromomycin이 첨가된 선발배지에서 정상배추의배축을 배양할 경우 얻어졌다. GUS양성반응으로 확인 한 결과 정상배추에서 9개체와 서울배추에서 3개체를 각각 얻었으며, 온실에서 생장한 후 $T_1$종자를 수확하였다. $T_1$ 종자를 다시 발아시켜 유식물체를 얻은 후 GUS양성반응을 확인함으로서 외래유전자가 안정적으로 발현하고 있음을 확인하였다. Hypocotyl explants of Chinese cabbage (us. 'Jeong Sang' and 'Seoul') produced adventitious shoots on Murashige and Skoog (MS) basal medium supplemented with 4mg/L $AgNO_3$, 5 mg/L acetosyringone, 4 mg/L 6-benzyladenine and 3mg/L alpha-naphthaleneacetic acid (SI) after cocoultivation with strains of Agrobacterium tumefaciens (LBA4404) harboring the pCAMBIA1301 and the $_PPTN290$ containing hygromycin-resistance gene and paromomycin-resistance gene as a selectable marker genes, respectively. There was a significant difference in the frequency of transgenic plants depending on antibiotics and cultivars used. Paromomycin was better than hygromycin, and cultivar 'Jeong-sang' was higher than 'c.v. Seoul' in the frequency of transgenic plants. In particular, the highest frequency (0.70%) of transgenic plants was obtained from selection medium (SI) containing 100mg/L paromomycin in c.v., 'Jeong-sang' GUS positive response were obtained 9 plants and 3 plants from the cultivars, 'Jeong-sang' and 'Seoul', respectively. They were grown to maturity in a greenhouse and normally produced $T_1$ seeds. GUS histochemical assay for progeny $(T_1)$ revealed that the transgenes were expressed in the plant genome.

Application of spirobiindane-based microporous poly(ether sulfone)s as polymeric binder on solid alkaline exchange membrane fuel cells

Choi, Jieun,Kim, Man-Ho,Han, Jun Young,Chae, Ji Eon,Lee, Won Hee,Lee, Young Moo,Lee, So Young,Jang, Jong Hyun,Kim, Jin Young,Henkensmeier, Dirk,Yoo, Sung Jong,Sung, Yung-Eun,Kim, Hyoung-Juhn Elsevier 2018 Journal of membrane science Vol.568 No.-

<P><B>Abstract</B></P> <P>In this report, we introduced spirobiindane group to poly(arylene ether sulfone) (PES) to build the structure of polymers with intrinsic microporosity (PIMs). A novel PESs (QOH-SBIs), which have spirobiindane and tetra(quaternary ammonium) hydroxide pendant moieties, were synthesized for anion-conducting binder material in membrane electrode assembly (MEA) of solid alkaline exchange membrane fuel cell (SAEMFC). The time-lag method was used to check the high gas permeability of the polymers. The high permeability is due to the micro-pores at the molecular level that is formed by the difference in chain thicknesses between two alternating units, thick spirobiindane group and thin arylene ether sulfone group. QOH-SBIs shows a semi-rigid chain conformation in a solution. The inter-chain spacing and chain conformation were measured with wide angle X-ray diffraction (WAXD) and small angle neutron scattering (SANS), respectively. High gas permeability directly affected the performance of SAEMFC. The MEA with spirobiindane-modified PES shows much higher maximum power density than that of spirobiindane-free PESs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Spiro moieties were introduced to PESs to design polymers of intrinsic microporosity. </LI> <LI> Difference in chain thickness create microporous channels for gas diffusion. </LI> <LI> Inter-chain spacing and chain conformation were calculated from with WAXD and SANS. </LI> <LI> Enhancing gas permeability of the electrode binder improved the cell performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Implementing an artificial synapse and neuron using a Si nanowire ion-sensitive field-effect transistor and indium-gallium-zinc-oxide memristors

Choi, Sungju,Kim, Seohyeon,Jang, Jungkyu,Ahn, Gumho,Jang, Jun Tae,Yoon, Jinsu,Park, Tae Jung,Park, Byung-Gook,Kim, Dong Myong,Choi, Sung-Jin,Lee, Seung Min,Kim, Eun Young,Mo, Hyun Sun,Kim, Dae Hwan Elsevier Sequoia 2019 Sensors and actuators. B Chemical Vol.296 No.-

<P><B>Abstract</B></P> <P>In this study, we implement an artificial synapse and neuron in a single platform by combining a silicon nanowire (SiNW) ion-sensitive field-effect transistor (ISFET), an indium-gallium-zinc-oxide (IGZO) memristor, and a voltage-controlled oscillator (VCO). The chemical and electrical operations of the synapse are emulated using the pH sensor operation of the ISFET and long-term potentiation/short-term plasticity of the IGZO memristor, respectively. The concentration of hydrogen ions in an electrolyte is successfully transformed via a VCO-based neuron into modulation of synaptic strength, i.e., the current of the memristor. It mimics the strength of the synaptic connection modulated by the concentration of the neurotransmitter. Thus, the chemical-electrical signal conversion in chemical synapses is clearly demonstrated. Furthermore, the proposed artificial platform can discriminate the chemical synapse from the electrical synapse and the path of the neuro-signal propagation and that of memorization/update of synaptic strength. This can potentially provide a new insight into the principles of brain-inspired computing that can overcome the bottleneck of the state-of-the-art von-Neumann computing systems.</P>

Effect of Korean Red Ginseng on metabolic syndrome

Sang Jun Yoon,Seul Ki Kim,Na Young Lee,Ye Rin Choi,Hyeong Seob Kim,Haripriya Gupta,Gi Soo Youn,Hotaik Sung,Min Jea Shin,Ki Tae Suk 고려인삼학회 2021 Journal of Ginseng Research Vol.45 No.3

Metabolic syndrome (MS) refers to a clustering of at least three of the following medical conditions: high blood pressure, abdominal obesity, hyperglycemia, low high-density lipoprotein level, and high serum triglycerides. MS is related to a wide range of diseases which includes obesity, diabetes, insulin resistance, cardiovascular disease, dyslipidemia, or non-alcoholic fatty liver disease. There remains an ongoing need for improved treatment strategies for MS. The most important risk factors are dietary pattern, genetics, old age, lack of exercise, disrupted biology, medication usage, and excessive alcohol consumption, but pathophysiology of MS has not been completely identified. Korean Red Ginseng (KRG) refers to steamed/dried ginseng, traditionally associated with beneficial effects such as anti-inflammation, anti-fatigue, anti-obesity, anti-oxidant, and anti-cancer effects. KRG has been often used in traditional medicine to treat multiple metabolic conditions. This paper summarizes the effects of KRG in MS and related diseases such as obesity, cardiovascular disease, insulin resistance, diabetes, dyslipidemia, or non-alcoholic fatty liver disease based on experimental research and clinical studies.