• Applied Microscopy
• /
• 제29권4호
• /
• pp.479-491
• /
• 1999

출생후 0일, 7일, 14일, 17일, 21일, 28일, 35일 그리고 성체의 흰쥐 전뇌 기저부의 Meynert 기저핵에서 ChAT 면역반응 신경세포의 분화를 면역조직화학적 및 전자현미경적 방법을 이용하여 조사하였다. 출생후 7일에서 성체까지 신경세포의 세포질에서 ChAT면역반응이 확인되었다. 특히 ChAT면역반응은 세포체의 세포질과 수상돌기에 고루 분포하였다. 전뇌 기저부의 ChAT면역반응 신경세포들은 발생에 따른 뇌 크기의 증대와 뇌조직의 분화에 따라 점차 수적 증가를 보였다. ChAT면역반응 신경세포들은 세포의 모양과 세포체의 장 단축의 비에 따라 6가지 형으로 분류되었다. 성체의 Meynert기저핵에서 원형은 9.4%, 난원형은 35.5%, 세장형은 32.1%, 방추형은 5.9%, 삼각형은 9.1% 그리고 다각형은 8.0%의 출현율을 보였다. 원형과 난원형 신경세포들의 출현율은 출생후 14일에서 가장 높아 각각 18.7%, 55.5%였고, 성체로 되면서 점차적으로 감소되었다. 또한, 세장형과 삼각형 신경세포들의 출현율은 출생후 21일에 가장 높아 각각 30.4%, 10.1%였고, 성체로 되면서 원형과 난원형 세포에서와 같이 점차적으로 감소하였다. 그러나 이들과는 다르게 방추형과 다각형 신경세포들의 출현율은 출생후 발생이 진행됨에 따라 점진적으로 증가하는 현상을 보였다. ChAT면역반응 신경세포체의 부피는 출생후 7일에 $1,083{\mu}m^3$로 제일 작았으나, 출생후 21일에서는 $5,045{\mu}m^3$로 최대치를 보였다. 그후 성체로 되면서 $2,731{\mu}m^3$로 감소되었다. 전자현미경적 관찰에서 출생후 21일의 경우 ChAT면역반응은 신경세포의 ribosome, polysome 그리고 RER에서 관찰되었으며, 대칭 및 비대칭 신경연접이 관찰되었다. 이상의 결과들로 미루어 흰쥐 전뇌 기저부 Meynert 기저핵에서의 ChAT면역반응 신경세포들은 출생후 발생과정에서 세포소기관과 신경돌기들의 분화에 따른 세포체부피의 증가, 분화된 세포형들의 출현율의 증가 및 세포의 손실이 없는 상태에서의 세포 응축 등의 과정을 통하여 세포들이 분화한다고 생각된다. 또한, Golgi체와는 다르게 ribosome, polysome그리고 RER들이 ChAT의 세포내 분포 및 생합성과 밀접한 관계를 같는 것으로 생각된다.

• 한국재료학회지
• /
• 제21권9호
• /
• pp.486-490
• /
• 2011

Nano-indium-coated ZnO:In thick films were prepared by a hydrothermal method. ZnO:In gas sensors were fabricated by a screen printing method on alumina substrates. The gas sensing properties of the gas sensors were investigated for hydrocarbon gas. The effects of the indium concentration of the ZnO:In gas sensors on the structural and morphological properties were investigated by X-ray diffraction and scanning electron microscopy. XRD patterns revealed that the ZnO:In with wurtzite structure was grown with (1 0 0), (0 0 2), and (1 0 1) peaks. The quantity of In coating on the ZnO surface increased with increasing In concentration. The sensitivity of the ZnO:In sensors was measured for 5 ppm $CH_4$ gas and $CH_3CH_2CH_3$ gas at room temperature by comparing the resistance in air with that in target gases. The highest sensitivity to $CH_4$ gas and $CH_3CH_2CH_3$ gas of the ZnO:In sensors was observed at the In 6 wt%. The response and recovery times of the 6 wt% indiumcoated ZnO:In gas sensors were 19 s and 12 s, respectively.

• Bulletin of the Korean Chemical Society
• /
• 제8권4호
• /
• pp.324-328
• /
• 1987

Reaction of Rh $(ClO_4)(CO)(PPh_3)_2$ (1) with trans-$C_6H_5CH = CHCH_2OH$ (2) produces a new cationic rhodium(Ⅰ) complex, $[Rh(trans-C_6H_5CH = CHCHO)(CO)(PPh_3)_2]ClO_4$ (3) where 2 is coordinated through the oxygen atom but not through the olefinic group. At room temperature under nitrogen, complex 1 catalyzes dehydrogenation, hydrogenolysis, and isomerization of 2 to give $trans-C_6H_5CH$ = CHCHO (4), trans-$C_6H_5CH = CHCH_3$ (5) and $C_6H_5CH_2CH_2CHO$ (6), respectively, and oligomerization of 2 whereas under hydrogen, complex 1 catalyzes hydrogenation of 2 to give $C_6H_5CH_2CH_2CH_2OH$ (7) and hydrogenolysis of 2 to 5 which is further hydrogenated to $C_6H_5CH_2CH_2CH_3$ (8). The dehydrogenation and hydrogenolysis of 2 with 1 suggest an interaction between the rhodium and the oxygen atom of 2, whereas the isomerization and hydrogenation of 2 with 1 indicate an interaction between the rhodium and the olefinic system of 2.

• Journal of Ginseng Research
• /
• 제47권4호
• /
• pp.561-571
• /
• 2023

Background: Escalating evidence shows that ginseng possesses an antiaging potential with cognitive enhancing activity. As mountain cultivated ginseng (MCG) is cultivated without agricultural chemicals, MCG has emerged as a popular herb medicine. However, little is known about the MCG-mediated pharmacological mechanism on brain aging. Methods: As we demonstrated that glutathione peroxidase (GPx) is important for enhancing memory function in the animal model of aging, we investigated the role of MCG as a GPx inducer using GPx-1 (a major type of GPx) knockout (KO) mice. We assessed whether MCG modulates redox and cholinergic parameters, and memory function in aged GPx-1 knockout KOmice. Results: Redox burden of aged GPx-1 KO mice was more evident than that of aged wild-type (WT) mice. Alteration of Nrf2 DNA binding activity appeared to be more evident than that of NFκB DNA binding activity in aged GPx-1 KO mice. Alteration in choline acetyltransferase (ChAT) activity was more evident than that in acetylcholine esterase activity. MCG significantly attenuated reductions in Nrf2 system and ChAT level. MCG significantly enhanced the co-localization of Nrf2-immunoreactivity and ChAT-immunoreactivity in the same cell population. Nrf2 inhibitor brusatol significantly counteracted MCG-mediated up-regulation in ChAT level and ChAT inhibition (by k252a) significantly reduced ERK phosphorylation by MCG, suggesting that MCG might require signal cascade of Nrf2/ChAT/ERK to enhance cognition. Conclusion: GPx-1 depletion might be a prerequisite for cognitive impairment in aged animals. MCG-mediated cognition enhancement might be associated with the activations of Nrf2, ChAT, and ERK signaling cascade.

• 복식
• /
• 제34권
• /
• pp.79-89
• /
• 1997

Comparison of Korean shroud with Chinese shroud are as follows. 1. Taetae Simeui P'oo Hansam Ko, Mal, Nukpaek, Kwatu, Ch'ungi Po-kkon Myokmok Ri Aksu Mo and Om were used the most inchina. However Mangkon Tapho Tanko Sotae Ri and Kop'o were used more widely in Korea. 2. The cloths of Chinese shroud were p'o, Paek and Kyun but those of the orean were paek Chu Chung and P'o The colors of the chinese and Koean shroud was Hyun Hun and white. 3. The size of the Cinese shroud is as follows. The size of the Ch ungi ws si-milar tothe size of jujube kernel the len-gth of Myokmok was one Ch'ok two Ch'on or one Ch'ok five Ch'on the length of Aksu was one Ch'ok two Ch'on and its width was five Ch'on. The chil of Mo reached the hands and the length of Sw-ae was three Ch'ok and the length of Om ws five Ch'on. the size of the Korean shroud was the same as Chinese shroud except that the size fo Myokmok and the lenth of Chil and Swae was seven Ch'ok respectively,. 4. In Korean and Chinese shroud Aksu was tied by the strings at two corners Myokmok was teid by the strings of four corners. The tip of the Om was divided and Mo wrapped the shole body. 5. The clothes of Soryom was nineteen Ch'ing in Korean and chinese shroud. The clothes of Taeryom in Kun were one hundred Ch'ing in the chinese and ninety Ch'ing in the Korean shroud. The imple-ment of Soryom were Kum Kyo Sangeui Saneui Ch'im Yok and Kyon in the Chinese shroud and were Kum Kyo Sangeui Saneui Ch'im Yok Kyonand Sinmyon in the Korean shroud. In the case of the implement of Taeryom the Chinese shroud had Kum Kyo Sangeui Saneui Ch'im and Yok the same as Korean shroud.

• Bulletin of the Korean Chemical Society
• /
• 제8권3호
• /
• pp.179-183
• /
• 1987

Reactions of $Rh(ClO_4)(CO)(AsPh_3)_2$ with unsaturated nitriles and aldehyde, L, produce a series of new cationic rhodium (I) complexes, $[RhL(CO)(AsPh_3)_2]ClO_4$ (L = $CH_2$ = CHCN, $CH_2$ = C($CH_3$)CN, trans-$CH_3CH$ = CHCN, $CH_2$ = CH$CH_2$CN, trans-$C_6H_5CH$ = CHCN, and trans-$C_6H_5CH$ = CHCHD) where L are coordinated through the nitrogen and oxygen, respectively but not through the ${\pi}$-system of the olefinic group. Dissociation constants for the reaction, $[RhL(CO)(AsPh_3)_2]ClO_4$ $\rightleftharpoons$ $Rh(ClO_4)(CO)(AsPh_3)_2$ + L, have been measured to be $1.20{\times}10^{-4}$ M (L = $CH_2$ = CHCN), $1.05{\times}10^{-4}$ M (L = $CH_2$ = C($CH_3$)CN, $3.26{\times}10^{-5}$ M (L = trans-$CH_3$CH = CHCN) and $6.45{\times}10^{-5}$ M (L = $CH_2$ = CH$CH_2$CN) in chlorobenzene at $25^{\circ}C, and higher than those of triphenylphosphine complexes, $[RhL(CO)(AsPh_3)_2]ClO_4$ where L are the corresponding nitriles that are coordinated through the nitrogen atom. The differences in dissociation constants seem to be predominantly due to the differences in ${\Delta}H$ (not due to the differences in ${\Delta}S$). The weaker Rh-N (unsaturated nitriles) bonding in $AsPh_3$ complexes than in $PPh_3$ complexes (based on ${\Delta}H$ values) suggests that the unsaturated nitriles in 2∼5 are good ${\sigma}$-donor and poor ${\pi}$-acceptor.

• Korea-Australia Rheology Journal
• /
• 제20권3호
• /
• pp.175-184
• /
• 2008

Chemical engineering (ChE) was conceived at the close of the 19th century as a new discipline which was designed to support then the newly-emerging industries, oil and petrochemical, by supplying the competent engineers equipped with the pertinent engineering fundamentals and skills. It helped the said industries meet the various demands and ramifications of the new pattern of the human civilization spurred by the advent of automobile transportation at the turn of the 20th century. Now ChE once again is ready to fulfill its societal responsibility as probably the most important discipline and profession in sustaining the $21^{st}$ century human civilization providing the needed engineers (ChErs) and technologies. In this study, it is attempted to analyze the role of ChE and ChErs in this context, focusing on the macroeconomic connections embedded in the discipline that allow us to envision the big pictures of the 21st century civilization where the wellbeing of the mankind invariably hinges on five essential industries, i.e., medical, pharmaceutical, energy, environment and materials. It can be argued that ChE is the only discipline that can encompass simultaneously all those five industries indispensable to sustain the 21 st century human civilization that can be termed the era of "enjoy-healthy-living-longer". It is also believed that the historical mission ChE and ChErs are supposed to fulfill now is even bigger than that they took on a hundred years ago and subsequently accomplished with remarkable success in food, clothing, shelter and entertainment industries introducing various technological innovations. The macroeconomic viewpoints are called upon in this study as were in the 2006 article (Hyun, 2006) but focusing on ChE and ChErs this time to view the connections embedded in ChE as the essential components in understanding the historical nature of the role and responsibility of ChE and ChErs. The new paradigm for ChE is also pondered over together with the frequently-cited technology concepts such as IT, BT, NT, ET and ST which are regarded intimately germane to the characteristics and perspectives of the $21^{st}$ century civilization.

• 한국환경과학회지
• /
• 제20권10호
• /
• pp.1233-1241
• /
• 2011

The main objective of this experimental investigation was $CH_4$ recovery from biogas generated in municipal and wastewater treatment plant. The polysulfone hollow fiber membrane was prepared in order to investigate the permeation properties of $CH_4$ and $CO_2$. Permeability of $CO_2$ in Polysulfone membrane was 11-fold higher than of $CH_4$ gas. A membrane pilot plant for upgrading biogas was constructed and operated at a municipal wastewater treatment plant. The raw biogas contained 66 ~ 68 Vol % $CH_4$, the balance being mainly $CO_2$. The effect of the operating pressure of feed and permeate side and feed flowrate on $CH_4$ recovery concentration and efficiency were investigated with double stage membrane pilot plant. The $CH_4$ concentration in the retentate stream was raised in these tests to 93 Vol % $CH_4$.

• Bulletin of the Korean Chemical Society
• /
• 제9권3호
• /
• pp.161-164
• /
• 1988

Infrared multiphoton decompositions (IRMPD) of $BrCH_2CH_2CH_2CH_2Cl$ were studied by using the pulsed $CO_2$laser. At 0.3 J laser energy the experimentally observed product ratios could be reasonably explained by the RRKM calculation with initial excitation energy of ca. 80 Kcal/mol. The pressure dependence of product yields led us to conclude that the collisional deactivation by the inert gas decreased the yield of low energy dissociation channel more significantly.

• Transactions on Electrical and Electronic Materials
• /
• 제11권1호
• /
• pp.11-14
• /
• 2010

The interaction of -$Al(CH_3)_2$ with -OH on a fully OH-terminated Si (001) surface was studied using density functional theory. Two sites for $Al(CH_3)_3$ to react with the -OH on the surface were identified. The $-Al(CH_3)_2$ product energetically favored the dimer-row site rather than the inter-row site because the Al atom of $-Al(CH_3)_2$ at the dimer-row site was attracted by the lone pair electrons of the O atom in the neighboring -OH. The energy barrier for the transfer of the $-Al(CH_3)_2$ between the two sites was 0.11 eV, and therefore, the $-Al(CH_3)_2$ at the inter-row site can easily transfer to the dimer-row site at room temperature.