• Title/Summary/Keyword: shock formation

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Detonation Characteristics of L. P. G /$O_2$Gas Mixture and the Self-Ignition Condition for the Formation of Detonative Wave (액화석유 가스 (L. P. G) 와 산소 혼합물의 폭발특성 및 점화조건에 관한 연구)

  • Sung Nak Choi;Kyu Sun Shim;Un Sik Kim;Sock Sung Yun;Ung Kim
    • Journal of the Korean Chemical Society
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    • v.30 no.4
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    • pp.394-402
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    • 1986
  • Detonation reaction in L.P.G./$O_2$ mixture gas has been investigated over the L.P.G. concentration range of 3∼45 volume%. The variation of detonation velocity with mixture ratio is very interesting as it shows and inflection point near at the stoichiometric ratio. This might be ascribed to the fact that the detonation reactions at fuel-rich condition and fuel-lean condition proceed via different mechanisms. The maximum detonation velocity of 2.65km/sec occurs not at stoichiometric ratio(${\phi}$=1) but at fuel-rich condition (${\phi}$=1.57). Assuming that a stable detonation wave must propagates with the constant velocity, The upper and lower limit of detonation were determined and found to be 40.0 and 3.40 L.P.G. volume% respectively. The shock-heating technique was also utilized for the measurement of self-ignition temperature onsetting a stable detonation wave at varous mixture ratios. The self-ignition temperature at stoichiometric ratio is $742{\pm}3{\circ}K$ and the self-ignition temperature increases as the mixture ratio deviates from the stoichiometric condition.

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Separation of Ferrous Materials from Municipal Solid waste Incineration Bottom Ash (생활폐기물(生活廢棄物) 소각(燒却) 바닥재의 자력선별(磁力選別)에 따른 ferrous material의 분리(分離) 특성(特性))

  • Um, Nam-Il;Han, Gi-Chun;You, Kwang-Suk;Cho, Hee-Chan;Ahn, Ji-Whan
    • Resources Recycling
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    • v.16 no.3 s.77
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    • pp.19-26
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    • 2007
  • The bottom ash of municipal solid waste incineration generated during incineration of municipal solid waste in metropolitan area consists of ceramics, glasses, ferrous materials, combustible materials and food waste and so on. Although the ferrous material was separated by the magnetic separation before the incineration process, of which content accounts for about $3{\sim}11%$ in bottom ash. The formation of a $Fe_3O_4-Fe_2O_3$ double layer(similar to pure Fe) on the iron surface was found during air-annealing in the incinerator at $1000^{\circ}C$. A strong thermal shock, such as that takes place during water-cooling of bottom ash, leads to the breakdown of this oxidation layer, facilitating the degradation of ferrous metals and the formation of corrosion products and it existed as $Fe_2O_3,\;Fe_3O_4\;and\;FeS_2$. So, many problems could occur in the use of bottom ash as an aggregate substitutes in construction field. Therefore, in this study, the separation of ferrous materials from municipal solid waste incineration bottom ash was investigated. In the result, the ferrous product(such as $Fe_2O_3,\;Fe_3O_4,\;FeS_2$ and iron) by magnetic separator at 3800 gauss per total bottom ash(w/w.%) accounted for about 18.7%, and 87.7% of the ferrous product was in the size over 1.18 mm. Also the iron per total bottom ash accounted for about 3.8% and the majority of it was in the size over 1.18 mm.

Hsp90 Inhibitor Induces Cell Cycle Arrest and Apoptosis of Early Embryos and Primary Cells in Pigs

  • Son, Myeong-Ju;Park, Jin-Mo;Min, Sung-Hun;Hong, Joo-Hee;Park, Hum-Dai;Koo, Deog-Bon
    • Reproductive and Developmental Biology
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    • v.35 no.1
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    • pp.33-45
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    • 2011
  • Heat shock protein 90 (Hsp90) is ATPase-directed molecular chaperon and affects survival of cancer cell. Inhibitory effect of Hsp90 by inducing cell cycle arrest and apoptosis in the cancer cell was reported. However, its role during oocyte maturation and early embryo development is very insufficient. In this study, we traced the effects of Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), on meiotic maturation and early embryonic development in pigs. We also investigated several indicators of developmental potential, including structural integrity, gene expression (Hsp90-, cell cycle-, and apoptosis-related genes), and apoptosis, which are affected by 17-AAG. Then, we examined the roles of Hsp90 inhibitor on viability of primary cells in pigs. Porcine oocytes were cultured in the NCSU-23 medium with or without 17-AAG for 44 h. The proportion of GV arrested oocytes was significantly different between the 17-AAG treated and untreated group (78.2 vs 34.8%, p<0.05). After completion of meiotic maturation, the proportion of MII oocytes was lower in the 17-AAG treated group than in the control group (27.9 vs 71.0%, p<0.05). After IVF, the percentage of penetrated oocytes was significantly lower in the 17-AAG treated group (25.2%), resulting in lower normal pronucleus formation (2PN of 14.6%). Therefore, the inhibition of meiotic progression by Hsp90 inhibitor played a critical role in fertilization status. Porcine embryo were cultured in the PZM-3 medium with or without 17-AAG for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without 17-AAG. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) showed that the number of containing fragmented DNA at the blastocyst stage increased in the 17-AAG treated group compared with control (7.5 vs 4.4, respectively). Blastocysts that developed in the 17-AAG treated group had low structural integrity and high apoptotic nuclei than those of the untreated control, resulting in decrease the embryonic qualities of preimplantation porcine blastocysts. The mRNA expressions of cell cycle-related genes were down-regulated in the 17-AAG treated group compared with control. Also, the expression of the pro-apoptotic gene Bax increased in 17-AAG treated group, whereas expression of the anti-apoptotic gene Bel-XL decreased. However, the expression of ER stress-related genes did not changed by 17-AAG. Cultured pESF cells were treated with or without 17-AAG and used for MIT assay. The results showed that viability of pESF cells were decreased by treatment of 17-AAG ($2{\mu}M$) for 24 hr. These results indicated that 17-AAG decreased cell proliferation and increased cell death. Expression patterns Hsp90 complex genes (Hsp70 and p23), cell cycle-related genes (cdc2 and cdc25c) and apoptosis-related genes (Bax and Bcl-XL) were significantly changed by using RT-PCR analysis. The spliced form of pXbp-1 product (pXbp-1s) was detected in the tunicamycin (TM) treated cells, but it is not detected in 17-AAG treated cells. In conclusion, Hsp90 appears to play a direct role in porcine early embryo developmental competence including structural integrity of blastocysts. Also, these results indicate that Hsp90 is closely associated with cell cycle- and apoptosis-related genes expression in developing porcine embryos.

The Effect of Exercise Training on Aβ-42, BDNF, GLUT-1 and HSP-70 Proteins in a NSE/ APPsw-transgenic Model for Alzheimer's Disease. (지구성 운동이 NSE/APPsw 알츠하이머 질환 생쥐의 인지능력, Aβ-42, BDNF, GLUT-1과 HSP-70 단백질 발현에 미치는 영향)

  • Eum, Hyun-Sub;Kang, Eun-Bum;Lim, Yea-Hyun;Lee, Jong-Rok;Cho, In-Ho;Kim, Young-Soo;Chae, Kab-Ryoung;Hwang, Dae-Yean;Kwak, Yi-Sub;Oh, Yoo-Sung;Cho, Joon-Yong
    • Journal of Life Science
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    • v.18 no.6
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    • pp.796-803
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    • 2008
  • Mutations in the APP gene lead to enhanced cleavage by ${\beta}-$ and ${\gamma}-secretase$, and increased $A{\beta}$ formation, which are closely associated with Alzheimer's disease (AD)-like neuropathological changes. Recent studies have shown that exercise training can ameliorate pathogenic phenotypes ($A{\beta}-42$, BDNF, GLUT-1 and HSP70) in experimental models of Alzheimer's disease. Here, we have used NSE/APPsw transgenic mice to investigate directly whether exercise training ameliorates pathogenic phenotypes within Alzheimer's brains. Sixteen weeks of exercise training resulted in a reduction of $A{\beta}-42$ peptides and also facilitated improvement of cognitive function. Furthermore, GLUT -1 and BDNF proteins produced by exercise training may protect brain neurons by inducing the concomitant expression of genes that encode proteins (HSP-70) which suppress stress induced neuron cell damages from APPsw transgenic mice. Thus, the improved cognitive function by exercise training may be mechanistically linked to a reduction of $A{\beta}-42$ peptides, possibly via activation of BDNF, GLUT-1, and HSP-70 proteins. On the basis of the evidences presented in this study, exercise training may represent a practical therapeutic management strategy for human subjects suffering from Alzheimer's disease.

Clinical Outcome of Emergency Coronary Artery Bypass Grafting after Failed Percutaneous Transluminal Coronary Angioplasty (경피적 관상동맥 성형술의 실패에 의해 발생한 응급환자의 임상경과)

  • Kim, Do-Kyun;Yoo, Kyung-Jong;Youn, Young-Nam;Yi, Gi-Jong;Lee, Sak;Chang, Byung-Chul;Kang, Meyun-Shick
    • Journal of Chest Surgery
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    • v.40 no.3 s.272
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    • pp.209-214
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    • 2007
  • Background: Failed percutaneous transluminal coronary angioplasty (PTCA) is occasionally required for emergency coronary artery bypass grafting (CABG). The aim of this study was to assess the outcome of patients receiving emergency CABG after failed PTCA. Material and Method: Between May 1988 and May 2005, 5712 patients underwent PTCA, where 84 (1.4%) failed. 27 patients underwent emergency CABG after failed PTCA. The mean age was $63.7{\pm}8.9\;(46{\sim}80)$ years, with 14 male patients (51.9%). Result: All patients underwent emergent surgical revascularization within 6 hours. 22 patients underwent conventional CABG and 5 underwent off-pump CABG. The causes of PTCA failure were coronary obstruction due to new thrombi formation during the procedure (n=4), coronary dissection (n=17), coronary artery rupture (n=3) and 3 due to other causes. The rate of in-hospital operative mortality after emergent operation was 18.5% (5/27). A univariate analysis revealed that patients who died more often had left anterior descending artery disease, a preprocedural shock status, postoperative use of multiple isotropics and postoperative use of intra-aortic balloon pump. The mean follow up duration was $53.6{\pm}63.4$ months. Conclusion: Although PTCA is known to be life saving, there is still a high risk for morbidity and mortality following emergency CABG after failed PTCA, despite the advancement in PTCA techniques. This result will help identify and more effectively treat patients selected for PTCA when emergency CABG is required.

Characteristics and pedigree selection of a shortened cultivation period strain in Lepista nuda (재배기간이 짧은 민자주방망이버섯 우량계통 선발 및 특성)

  • Jeon, Jong-Ock;Lee, Kwan-Woo;Lee, Kyoung-Jun;Kim, Min-Ja;Kim, In-Jae;Kim, Young-Ho
    • Journal of Mushroom
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    • v.18 no.4
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    • pp.331-338
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    • 2020
  • This study was conducted to cultivate new Lepista nuda varieties with shorter cultivation period and better fruiting body compared to that of wild strains, for mass production and commercial application. Eighteen genetic resources of L. nuda were collected and grown in boxes using rice straw-fermented growth medium. Four lines with fruiting bodies were formed and selected as cross-breeding lines. Although 657 combinations were crossed through monospore crossing, only 17 combinations were bred between the 'CBMLN-19' line and the 'CBMLN-30' line. Among them, 8 lines with fast mycelial growth and high density were selected. After inoculating the rice straw-fermented growth medium with 14 genetic resources and 8 cross-breeding lines, their incubation period was investigated. Six of the cross-breeding lines completed their incubation in 20 days, while 7 of the 14 genetic resources took more than 40 days to complete their incubation, reducing the incubation period by more than 20 days in most cross-breeding lines. After the incubations were completed, the clay loam soil was covered with for post-cultivation, and when the mycelial cultivation was complete, the formation of fruiting bodies was induced after scraping the mycelial bodies under these environmental conditions: 14℃, 95% relative humidity or higher, and 1,500 to 2,000 ppm CO2 concentration. The temperature was reduced to 6℃ at night, resulting in a low temperature shock. Thus, 4 lines of fruiting bodies occurred from two genetic resources 'CBMLN-31' and 'CBMLN-44' and two cross-bred lines 'CBMLN-96' and 'CBMLN-103'. After inoculation, the longest period for fruiting bodies to occur was 100 days for the control:, the genetic resource 'CBMLN-31', and the shortest period (45 days) was observed for the cross-breeding line 'CBMLN-103'. The result of the investigation of the fruiting body characteristics shows that the cross-bred line 'CBMLN-103' showed a small form with 1.9 g of individual weight and 123validstipes per box, which was the highest incidence among the four lines. Another cross-bred line, 'CBMLN-96', had an individual weight of 5.5 g, which is larger than that of 'CBMLN-103'; however, the number of valid stipes per box was 30 less than that of 'CBMLN-103'. Quantity analysis showed that the control, 'CBMLN-31', had the highest quantity of 783 g per box, followed by the cross-bred line, 'CBMLN-96' with 165 g per box, and then the 'CBMLN-103' with 232 g. The quantity of the two crossbred lines was lower than that of the control 'CBMLN-31'; however, the amount of fruiting bodies was higher, and the cultivation period was shortened by 32 to 33 days. Therefore, these two lines would be selected as superior lines.

The influence of the four noted physicians of Geum-Won era on the completion of the medicine in the Chosun dynasty (금원사대가의학(金元四大家醫學)이 조선조의학(朝鮮朝醫學) 형성(形成)에 미친 영향(影響))

  • Cheong, Myeon;Hong, Won Sik
    • Journal of Korean Medical classics
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    • v.9
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    • pp.432-552
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    • 1996
  • The influence of the four noted physicians of Geum-Won era(金元代) on the completion of the medicine in the Chosun dynasty(朝鮮朝) can be summarized as follows. 1. The four noted physicians of Geum-Won era were Yoo-Wan-So(劉完素), Jang-Jong-Jung(張從正), Lee-Go(李杲), Ju-Jin-Heung(朱震亨). 2. Yoo-Wan-So(劉完索) made his theory on the basic of Nae-Kyung("內經") and Sane-Han-Lon("傷寒論"), his idea of medicine was characterized in his books, for exemple, application of O-Oon-Yuk-Ki(五運六氣), Ju-Wha theory(主火論) and hang-hae-seng-je theory(亢害承制論). from his theory and method of study, many deviations of oriental medicine occurred. He made an effort for study of Nae-Kyung, which had been depressed for many years, on the contrary of the way old study that Nae-Kyung had been only explained or revised, he applied the theory of Nae-Kyung to clinical care. The theory of Yuk-Gi-Byung-Gi(六氣病機) and On-Yeul-Byung(溫熱病) had much influenced on his students and posterities, not to mention Jang-Ja-Wha and Ju-Jin-Heung, who were among the four noted physicians therefore he became the father of Yuk-Gi(六氣) and On-Yeul(溫熱) schools. 3. Jang-Jong-Jung(張從正) emulated Yoo-Wan-So as a model, and followed his Yuk-Gi-Chi-Byung(六氣致病) theory, but he insisted on the use of the chiaphoretic, the emetic and the paregoric to get rid of the causes, specially he insisted on the use of the paregoric, so they called him Gong-Ha-Pa(攻下派). He insisted on the theory that if we would strenthen ourselves we should use food, id get rid of cause, should use the paregoric, emetic and diaphoretic. Jang-Jong-Jung'S Gang-Sim-Wha(降心火) theory, which he improved Yoo-Wan-So's Han-Ryang(寒凉) theory influenced to originate Ju-Jin-Heung'S Ja-Eum-Gang-Wha(滋陰降火) theory. 4. Lee-Go(李杲) insisted on the theory that Bi-Wi(脾胃) played a loading role in the physiological function and pathological change, and that the internal disease was originated by the need of Gi(氣) came from the disorder of digestive organs, and that the causes of internal disease were the irregular meal, the overwork, and mental shock. Lee-Go made an effort for study about the struggle of Jung-Sa(正邪) and in the theory of the prescription he asserted the method of Seung-Yang-Bo-Gi(升陽補氣), but he also used the method of Go-Han-Gang-Wha(苦寒降火). 5. The authors of Eui-Hak-Jung-Jun("醫學正傳"), Eui-Hak-Ib-Moon("醫學入門"), and Man-Byung-Whoi-Choon("萬病回春") analyzed the medical theory of the four noted physicians and added their own experiences. They helped organizing existing complicated theories of the four noted physicians imported in our country, and affected the formation of medical science in the Choson dynasty largely. Eui-Hak-Jung-Jun("醫學正傳") was written by Woo-Dan(虞槫), in this book, he quoted the theories of Yoo-Wan-So, Jang-Jong-Jung, Lee-Go, Ju-Jin-Heung, especially, Ju-Jin-Heung was respected by him, it affected the writing of Eui-Lim-Choal-Yo("醫林撮要"). Eui-Hak-ib-Moon("醫學入門"), written by Lee-Chun(李杲), followed the medical science of Lee-Go and ju-jin-heung from the four noted physicians of Geum-Won era. Its characteristics of Taoism, idea of caring of health, and organization affected Dong-Eui-Bo-Kham("東醫寶鑑"). Gong-Jung-Hyun(龔延賢) wrote Man-Byung-Whoi-Choon("萬病回春") using the best part of the theories of Yoo-Wan-So, Jang-Jong-Jung, Lee-Go, Ju-Jin-Heung, this book affected Dong-Eui-Soo-Se-Bo-Won("東醫壽世保元") partly. 6. our medical science was developed from the experience of the treatment of disease obtained from human life, these medical knowledge was arranged and organized in Hyang-Yak-Jib-Sung-Bang("鄕藥集成方"), medical books imported from China was organized in Eui-Bang-Yoo-Chwi("醫方類聚"), which formed the base of medical development in the Chosun dynasty. 7. Eui-Lim-Choal-Yo("醫林撮要") was written by Jung-Kyung-Sun(鄭敬先) and revised by Yang-Yui-Soo(楊禮壽). It was written on the base of Woo-Dan's Eui-Jung-Jun, which compiled the medical science of the four noted physicians of Geum-Won era. It contained confusing theories of the four noted physicians of Geum-Won era and organized medical books of Myung era, therefore it completed the basic form of Byun-Geung-Non-Chi (辨證論治) influenced the writing of Dong-Eui-Bo-Kham("東醫寶鑑"). 8. Dong-Eui-Bo-Kham("東醫寶鑑") was written on the base of basic theory of Eum-Yang-O-Haeng(陰陽五行) and the theory of respondence of heaven and man(天人相應說) in Nae-Kyung. It contained several theories and knowledge, such as the theory of Essence(精), vitalforce(氣), and spirit(神) of Taoism, medical science of geum-won era, our original medical knowledge and experience. It had established the basic organization of our medical science and completed the Byun-Geung-Non-Chi (辨證論治). Dong-Eui-Bo-Kham developed medical science from simple medical treatment to protective medical science by caring of health. And it also discussed human cultivation and Huh-Joon's(許浚) own view of human life through the book. Dong-Eui-Bo-Kham adopted most part of Lee-Go(李杲) and Ju-Jin-Heung's(朱震亨) theory and new theory of "The kidney is the basis of apriority. The spleen is the basis of posterior", so it emphasized the role of spleen and kidney(脾腎) for Jang-Boo-Byung-Gi(臟腑病機). It contained Ju-Jin-Heung's theory of the cause and treatment of disease by colour or fatness of man(black or white, fat or thin). It also contained Ju-Jin-Heung's theory of "phlegm break out fever, fever break out palsy"(痰生熱 熱生風) and the theory of Sang-Wha(相火論). Dong-Eui-Bo-Kham contained Lee-Go's theory of Wha-Yu-Won-Bool-Yang-Lib (火與元氣不兩立論) quoted the theory of Bi-Wi(脾胃論) and the theory of Nae-Oi-Sang-Byun(內外傷辨). For the use of medicine, it followed the theory by Lee-Go. lt used Yoo-Wan-So'S theory of Oh-Gi-Kwa-Keug-Gae-Wi-Yul-Byung(五志過極皆爲熱病) for the treatment of hurt-spirit(傷神) because fever was considered as the cause of disease. It also used Jang-Jons-Jung's theory of Saeng-Keug-Je-Seung(生克制勝) for the treatment of mental disease. 9. Lee-je-ma's Dong-Eui-Soo-Se-Bo-Won("東醫壽世保元") adopted medical theories of Song-Won-Myung era and analyzed these theories using the physical constitutional theory of Sa-Sang-In(四象人). It added Dong-Mu's main idea to complete the theory and clinics of Sa-Sang-Eui-Hak(四象醫學). Lee-Je-Ma didn't quote the four noted physicians of Geum-Won era to discuss that the physical constitutional theory of disease and medicine from Tae-Eum-In(太陰人), So-Yang-In(少陽人), So-Eum-In(少陰人), and Tae-Yang-In(太陽人) was invented from their theories.

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