Highly Ordered Microscale-Pyramidal-Structure-Arrayed Silicon Membranes for Filter Applications

Hwang, Shinae,Lee, Seongjae,Ko, Jaehyeon,Jang, Moongyu American Scientific Publishers 2018 Journal of Nanoscience and Nanotechnology Vol.18 No.9

Micro-pyramidal structure fabrication by Si (100) KOH wet etching

Shinae Hwang,Kyungsuk Lim,Hyeseon Shin,Ilki Han,Seongjae Lee,Moongyu Jang 한국진공학회 2017 한국진공학회 학술발표회초록집 Vol.2017 No.2

Development of Blue Light Cut Films Using a Roll-to-Roll Nano Micro Coating System

Hwang, Joong Kook,Shina, Hoon-Kyu,Chang, Sang-Mok The Korean Institute of Electrical and Electronic 2016 Transactions on Electrical and Electronic Material Vol.17 No.3

In this study a coating experiment was performed to fabricate blue light cut films, which represent a 390~430 nm cut off rate of more than 40% and a transmittance rate of more than 90%, using a roll-to-roll nano micro coating system. The study also analyzed the characteristics of the blue light cut films. Thus, the hardness, which is more than 3H, is ensured through fabricating films using a Sol-Gel process that will determine the proper hardness level. Also, the experiment shows excellent results by cutting blue light through a mixing blue light powder.

The relationship between immediately afterbirth oral suction matrix metalloproteinase-8 and acute histologic chorioamnionitis in preterm birth

( Shina Jang ),( Su Gyung Jung ),( Hwoa Yeon Choi ),( Eun Ae Jo ),( Hyung Eun Choi ),( Sung Ook Hwang ),( Soo Ran Choi ) 대한산부인과학회 2019 대한산부인과학회 학술대회 Vol.105 No.-

Objective: Acute histologic chorioamnionitis (HCA) is frequently observed after preterm birth and is associated with the risk of neonatal morbidity and mortality. We aimed to evaluate the relationship between immediately afterbirth oral suction matrix metalloproteinase-8 (MMP-8) and acute HCA in preterm birth. Methods: 93 consecutive patients who delivered preterm neonates (gestational age, from 24+0 weeks to 36+6 weeks) were included. The concentrations of immediately afterbirth oral suction MMP-8 and interleukin-8 (IL-8) were measured by ELISA. Acute HCA was defined as the presence of neutrophils infiltration into the fetal membranes. Logistic regression analysis was used for analysis. Results: Immediately afterbirth oral suction MMP-8 concentrations were significantly higher in patients with acute HCA than in those without acute HCA (median [range]; 65.3ng/ml [0.03-12479.6] versus 9.86ng/ml [0.02-1808.2], p=0.027). There was a strong association between MMP-8 and IL-8 (p<0.001). The diagnostic indices of MMP-8 (cutoff, 39.7ng/ml) in the identification of acute HCA were: sensitivity of 57.7% specificity of 83.6%. Based on a multivariable logistic regression analysis, immediately afterbirth oral suction MMP-8 (p=0.008, odds ratio [OR]=5.36, 95% confidence interval [CI]=1.56-18.37) was associated acute HCA. Conclusion: There is a significantly association between increased levels of immediately afterbirth oral suction MMP-8 and acute HCA.

The Evaluation of Hole Mobility Characteristics with Surface Roughness

Shin, Hyeseon,Lim, Kyungsuk,Hwang, Shinae,Han, Il-Ki,Jang, Moongyu American Scientific Publishers 2017 Journal of Nanoscience and Nanotechnology Vol.17 No.10

<P>Hole mobility characteristics were investigated as a function of the temperature and effective field with surface roughness. The temperature varied from 80 K to 340 K and from 93 K to 533 K in Hall effect measurement and variable temperature probe station measurement, respectively. From the Hall effect measurement in bulk silicon, there was no difference of hole mobility in either the roughness controlled or the roughened samples. In SOI substrate, the hole mobility measured by transconductance showed dominant phonon scattering dependence at high effective field. In addition, the hole mobility was severely decreased at the roughened sample with the increase of temperature due to the increased phonon and surface roughness scattering. Surface roughness scattering was dominant at high effective field and was expected to be dominant at low temperature.</P>

The Characteristics of Temperature/Impedance Integrated Sensors

Lim, Kyungsuk,Shin, Hyeseon,Hwang, Shinae,Jang, Moongyu American Scientific Publishers 2017 Journal of Nanoscience and Nanotechnology Vol.17 No.11

<P>Temperature/impedance integrated sensors are manufactured using a semiconductor process for the simultaneous monitoring of the temperature and impedance variations. The temperature Coefficient of Resistance (TCR) value of a temperature sensor is evaluated as 1982.91 ppm/C from 34 to 40 C and 1957.98 ppm/C from 57 to 63 C, respectively, giving the temperature inaccuracy less than +0.05 'C. Using a temperature/impedance integrated sensor, the volatilization rates of acetone, methanol and isopropyl alcohol are measured simultaneously. The temperature changed from 1 to 3 C and capacitance changed from 10% to 90% depending on the type of solvents. Moreover, the electrocatalysis phenomenon between platinum and methanol is monitored from impedance measurement.</P>

L-trans-pyrrolidine-2,4-dicarboxylate (PDC) induces Excitotoxic and Oxidative Neuronal Death in Cultured Cortical Neurons

Choi, Seung Joon,Hwang, Shinae,Kim, Do Kyung,Kim, Jong-Keun KOREAN ACADAMY OF ORAL BIOLOGY 2009 International Journal of Oral Biology Vol.34 No.2

L-trans-pyrrolidine-2,4-dicarboxy1ate (PDC) is a potent inhibitor of glutamate transporters. In our current study, we investigated whether the neuronal death induced by PDC involves mechanisms other than excitotoxicity in mixed mouse cortical cultures. Cortical cultures at 13-14days in vitro were used and cell death was assessed by measuring the lactate dehydrogenase efflux into bathing media. Glutamate and PDC both induced neuronal death in a concentration-dependent manner but the neurotoxic effects of glutamate were found to be more potent than those of PDC. Treatment with 10,100 and 200 μM PDC equally potentiated 50 μM glutamate-induced neuronal death. The neuronal death induced by 75 μM glutamate was almost abolished by treatment with the NMDA antagonists, MK-801 and AP-5, but was unaffected by NBQX (an AMPA antagonist), trolox (antioxidant), BDNF or ZVAD-FMK (a pan-caspase inhibitor). However, the neuronal death induced by 200 μM PDC was partially but significantly attenuated by single treatments with MK-801, AP-5, trolox, BDNF or ZVAD-FMK but not NBQX. Combined treatments with MK-801 plus trolox, MK-801 plus ZVAD-FMK or MK-801 plus BDNF almost abolished neuronal death, whereas combined treatments with trolox plus ZVAD-FMK, trolox plus BDNF or ZVAD-FMK plus BDNF did not enhance the inhibitory action of any single treatment with these drugs. These results demonstrate that the neuronal death induced by PDC involves not only in the excitotoxicity induced by the accumulation of glutamate but also the oxidative stress induced by free radical generation. This suggests that apoptotic neuronal death plays a role in PDC-induced oxidative neuronal injury.

Effects of (⁣)-Epigallocatechin-3-gallate on Brain Infarction and the Activity Change of Matrix Metalloproteinase-9 Induced by Middle Cerebral Artery Occlusion in Mice

Yong Ri Qian,Ji Hyun Kook,Shinae Hwang,Do Kyung Kim,Jong-Keun Kim 대한생리학회-대한약리학회 2007 The Korean Journal of Physiology & Pharmacology Vol.11 No.3

Matrix metalloproteinases (MMPs) can degrade a wide range of extracellular matrix components. It has been reported that MMP-9 are activated after focal ischemia in experimental animals. (⁣)-Epigallocatechin-3-gallate (EGCG), a major constituent of green tea polyphenols, is a potent free radical scavenger and reduces the neuronal damage caused by oxygen free radicals. And it has been known that EGCG could reduce the infarction volume in focal brain ischemia and inhibit MMP-9 activity. To delineate the relationship between the anti-ischemic action and the MMP-9-inhibiting action of EGCG, we investigated the effect of EGCG on brain infarction and the activity of matrix metalloproteinase-9 induced by permanent middle cerebral artery occlusion (pMCAO) in ICR mice. EGCG (40 mg/kg, i.p. 15∼30 min prior to MCAO) significantly decreased infarction volume at 24 hr after MCAO. GM 6001 (50 mg/kg, i.p. 15∼30 min prior to MCAO), a MMP inhibitor, also significantly reduced infarction volume. In zymogram, MMP-9 activities began to increase at ipsilateral cortex at 2 hr after MCAO, and the increments of MMP-9 activities were attenuated by EGCG treatment. Western blot for MMP-9 also showed patterns similar to that of zymogram. These findings demonstrate that the anti-ischemic action of EGCG in mouse focal cerebral ischemia involves its inhibitory effect on MMP-9.

전기전도도를 이용한 하천 수질특성 평가방법 연구

장신요(Shinyo Chang),황광호(Kwangho Hwang),이희진(Heejin Lee),정유진(Yujin Jeung),김신아(Shina Kim),조우현(Woohyun Joe),이상미(Sangmi Lee) 대한환경공학회 2022 대한환경공학회 학술발표논문집 Vol.2022 No.11

생쥐에서 Pilocarpine에 의한 경련이 해마의 신경세포사멸, 이끼섬유발아 및 신경발생에 미치는 영향

이상현(Sang-Hyeon Lee),국지현(Ji-Hyun Kook),황신애(Shinae Hwang),김종근(Jong-Keun Kim),배춘상(Choon-Sang Bae) 대한체질인류학회 2011 해부·생물인류학 (Anat Biol Anthropol) Vol.24 No.4

해마 치아이랑은 지속적인 경련 후 이끼섬유발아(mossy fiber sprouting)가 일어나는 부위일 뿐만 아니라 성체 뇌의 신경발생(neurogenesis)이 일어나는 부위로 많은 연구의 대상이 되고 있다. 본 논문은 pilocarpine에 의한 발작을 이용한 해마 및 치아이랑에서 신경세포사멸, 이끼섬유발아 및 신경발생의 변동을 조사하여 이들 3자간의 상관관계를 규명하고자 하였다. 수컷 ICR 생쥐와 C57BL/6 생쥐에 pilocarpine을 처리하여 발작을 유발하였으며 처음 4시간 동안 발작양상을 관찰하여 Racine의 5등급 scale에 중 적어도 3등급 이상인 동물을 실험에 사용하였다. 신경세포사멸은 Fluoro-Jade C(FJC) 염색으로, 이끼섬유발아는 NeoTimm 염색으로, 신경발생은 bromodeoxyuridine(BrdU) 주사 후 이에 대한 면역조직염색으로 평가하였다. 본 실험에서 사용한 모든 동물에서 pilocarpine(300 mg/kg, ip) 투여에 의해 3등급 이상의 발작을 일으켰으며 발작 반응은 ICR 생쥐에서 C57BL/6 생쥐에서 보다 더 강하게 나타났다. 즉 ICR 생쥐의 평균 발작 등급이 4.37로 C57BL/6 생쥐의 3.22보다 유의하게 강하였다. 그러나 3등급 이상의 발작이 시작하는데 걸린 시간은 15~20분 사이로 차이가 없었다. 약물주입 4시간 후 ICR 생쥐에서는 FJC염색 상 해마 문(hilus)에서 사멸세포가 관찰되었으나, C57BL/6 생쥐에서는 관찰되지 않았다. 24시간 이후부터는 두 strain 모두에서 CA1 및 CA3 피라밋세포의 사멸도 관찰되었다. 이 세포사멸은 약물투여 후 3일에 가장 강하였으며 l주일 후에는 거의 관찰할 수 없었다. 신경발생을 나타내는 해마의 BrdU 양성세포수는 대조동물의 경우 C57BL/6 생쥐가 ICR 생쥐보다 유의하게 많았다. BrdU 양성세포수는 약물투여 2일 후에 대조군에 비해 유의하게 증가하였으며, 8일 후에는 더 큰 증가를 보인 후 15일 후에는 대조군 수준으로 돌아왔다. 두 strain 모두에서 약물투여 후 해마 신경발생의 증가를 보였으나 대조동물과의 비로 비교하면 ICR 생쥐가 C57BL/6 생쥐에 비해 더 큰 증가를 보였다. 이끼섬유발아는 약물투여 2주 후에 약하게 나타나서 4주 후에는 더 강해졌으며 두 strain 간에 차이는 관찰 할 수 없었다. 이상의 성적은 pilocarpine에 의한 발작의 정도와 신경세포사멸 및 신경발생 간에는 서로 상관관계가 있지만 이들과 이끼섬유발아 간에는 직접적인 상관관계가 없음을 시사한다. Present study was performed to delineate the inter-relationship among neuronal death, mossy fiber sprouting (MFS) and neurogenesis in hippocampal formation of pilocarpine-treated mice. Status epilepticus was induced by intraperitoneal administration of 300 mg/kg pilocarpine in male ICR and C57BL/6 mouse. The severity of seizure was evaluated using 5 grades of Racine scales for first 4 hr after pilocarpine injection. Fluro-Jade C (FJC) staing, NeoTimm"s staining and immunohistochemistry for BrdU were employed to evaluate neuronal cell death, MFS and neurogenesis, respectively. All animals in the present study induced seizures over grade 3 of Racine scale by pilocarpine injection. ICR mice show higher seizure severity (mean Racine scale; 4.37) than C57BL/6 mice do (mean Racine scale; 3.22), while the latency times for the first seizure over Racine scale grade 3 are from 15 min to 20 min and showed no difference between the 2 strains. In ICR mouse, numerous FJC-positive cells in hilus of hippocampus were detected at 4 h after pilocarpine injection, while they were not detected at that time in C57BL/6 mouse. The number of FJC-positive neuronal cells, which were densely found in the pyramidal layer of CA1, CA3 and hilus polymorphic regions of hippocampus, reached peak at 3 days after injection and then few cells were found at 7 days after injection in both strains. In control animals, BrdU positive cells in dentate subgranular layer which represent the hippocampal neurogenesis were more numerous in C57BL/6 than in ICR. The number of BrdU positive cells significantly increased at 2 days after pilocarpine injection and reached the peak at 8 days after injection and returned to control level at 15 day after injection in both strains. The percent increase of the BrdU positive cell was more prominent in ICR mouse. MFS was found at 2 weeks after the injection and the intensity of MFS was getting strong at 4 weeks after injection. There was no differences in MFS grading between 2 strains. These results suggest that there are some inter-relationships among the seizure severity, hippocampal neuronal cell death and hippocampal neurogenesis, but they don"t have any significant relationships with the mossy fiber sprouting from dentate granule cells.