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Crystal Structure of an Acetylene Sorption Complex of Vacuum Dehydrated Fully Cadmiumfiil-Exchanged Zeolite A (완전히 카드뮴 이온으로 교환된 제올라이트 A를 진공 탈수한 후 아세틸렌 기체로 흡착한 결정구조)

  • Koh, Kwang-Nak;Han, Young-Wook;Kim, Yang
    • Korean Journal of Crystallography
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    • v.2 no.1
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    • pp.17-22
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    • 1991
  • The crystal structure of an acetylene sorption complex of vacuum dehydrated fully Cda+ _exchanged zeolite A has been determined from three-dimensional X-ray diffraction data gathered by counter method. The structure was solved and refined in the cubic space group Pm3m at 294(1) K, a=12.202(3) A and Z=1. We crystal was prepared by dehydration at 723 K and 2.67×104 Pa for 2 days, followed by exposure to 1.60×104 Pa of acetylene gas at 298(1) K. All six Cd2+ions per unit cell are associated with 6-oxgen rings of the aluminosilicate framework. They are distributed over two distinguished threefold axes of unit cell; two of these Cd2+ ions are recessed 0.694 into the sodalite unit from (111) plane of three 0(3)'s and each approaches three framework oxides; the other four Cd2+ ions extend approximately 0.586A into the large cavity. The four Cd2+ ions are in a near tetrahedral environment, 2.220(9)A from·three framework oxide ions and 2.74(7) A from each carbon atom of an acetylene molecule(which is here counted as a monodentate ligand). Full matrix least squares refinement converged to the final error indices R1=0.093 and R2=0.105 using the 292 independent reflections for which I>3σ(I).

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The bifunctional effect of propofol on thromboxane agonist (U46619)-induced vasoconstriction in isolated human pulmonary artery

  • Hao, Ning;Wang, Zhaojun;Kuang, Sujuan;Zhang, Guangyan;Deng, Chunyu;Ma, Jue;Cui, Jianxiu
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.6
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    • pp.591-598
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    • 2017
  • Propofol is known to cause vasorelaxation of several systemic vascular beds. However, its effect on the pulmonary vasculature remains controversial. In the present study, we investigated the effects of propofol on human pulmonary arteries obtained from patients who had undergone surgery. Arterial rings were mounted in a Multi-Myograph system for measurement of isometric forces. U46619 was used to induce sustained contraction of the intrapulmonary arteries, and propofol was then applied (in increments from $10-300{\mu}m$). Arteries denuded of endothelium, preincubated or not with indomethacin, were used to investigate the effects of propofol on isolated arteries. Propofol exhibited a bifunctional effect on isolated human pulmonary arteries contracted by U46619, evoking constriction at low concentrations ($10-100{\mu}m$) followed by secondary relaxation (at $100-300{\mu}m$). The extent of constriction induced by propofol was higher in an endothelium-denuded group than in an endothelium-intact group. Preincubation with indomethacin abolished constriction and potentiated relaxation. The maximal relaxation was greater in the endothelium-intact than the endothelium-denuded group. Propofol also suppressed $CaCl_2$-induced constriction in the 60 mM $K^+$-containing $Ca^{2+}$-free solution in a dose-dependent manner. Fluorescent imaging of $Ca^{2+}$ using fluo-4 showed that a 10 min incubation with propofol ($10-300{\mu}m$) inhibited the $Ca^{2+}$ influx into human pulmonary arterial smooth muscle cells induced by a 60 mM $K^+$-containing $Ca^{2+}$-free solution. In conclusion, propofol-induced arterial constriction appears to involve prostaglandin production by cyclooxygenase in pulmonary artery smooth muscle cells and the relaxation depends in part on endothelial function, principally on the inhibition of calcium influx through L-type voltage-operated calcium channels.

Studies on the Structure and Production Processes of Biotic Communities in the Coastal Shallow Waters of Korea 3. Age and Growth of Spisula sachalinensis from the Eastern Waters of Korea (한국연안천해생물군집의 구조와 생산 3. 동해산 북방대합 (Spisula sachalinensis)의 연령과 성장)

  • KANG Yong Joo;KIM Chong Kawn
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.2
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    • pp.82-87
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    • 1983
  • The aging and growth of Spisula sachalinensis from Ingu over the period from December 1981 through November 1982 were studied. The rings on the shell were used as the character for age determination. The ring where the translucent zone shifts to the opaque one was regarded as an annulus. The time of its formation was estimated by monthly variations of marginal growth rate in the shell. It was formed once a year over the period from August through September. The shell length at the formation of the annulus was estimated by taking the mean shell length corresponding to each of the annual ring. From analysis of mean shell length at the formation of the annulus, von Bertalanffy's growth equation was estimated as follows; $l_t=126.38(1-e^{-0.262(t-0.656)})\;W_t=485.85(1-e^{-0.262(t-0.656)})^3$ Back-calculated shell lengths estimated from this equation was quite consistent with actual shell lengths.

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Age and Growth of Small Yellow Croaker, Larimichthys polyactis in the South Sea of Korea (한국 남해 참조기의 연령과 성장)

  • Kim, Yeong Hye;Lee, Sun Kil;Lee, Jae Bong;Lee, Dong Woo;Kim, Young Seop
    • Korean Journal of Ichthyology
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    • v.18 no.1
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    • pp.45-54
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    • 2006
  • Age and growth of the small yellow croaker, Larimichthys polyactis were estimated using right sagittal otoliths of 506 fish specimens from March to December, 2002 and from January to February, 2005 in the South Sea, part of the East China Sea of Korea. Examination of outer margins of the otolith showed that the opaque zone was formed once a year. Marginal increment of the otolith formed annual rings from May and June at the beginning of spawning season. In the relationship between total length and body weight, a multiplicative error structure was assumed because variability in growth increased as a function of the length, and the estimated equation was $BW=0.0044TL^{3.2502}$ ($R^2=0.97$). The relative growth as body weight at total length has significant difference between females and males (P<0.05). For describing growth of the small yellow croaker, Larimichthys polyactis a von Bertalanffy growth model was adopted. The von Bertalanffy growth curve had an additive error structure and the growth parameters estimated from non-linear regression were $L_{\infty}=33.88cm$, K=0.20/year and $t_0=-2.39year$. Growth at age of males and females shows no significant difference (P>0.05). Most examined fish were 1, 2 and 3 years old, although the oldest fish were 7 old for males and 8 for females.

Study on the Reproduction and Growth of Iksookimia koreensis Kim (Pisces: Cobitidae) in the Namdae Stream, Cheorwon-gun, Gangwon-do Korea (강원도 철원군 남대천에 서식하는 참종개의 성장과 번식에 관한 연구)

  • Kim, Dohong;Cho, Hae-Young;Lee, Ho-Sa
    • Korean Journal of Ichthyology
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    • v.20 no.1
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    • pp.21-27
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    • 2008
  • A total sample of 215 specimens of the Iksookimia koreensis was collected monthly from June 2004 to June 2005 in the Namdae stream, Cheorwon-gun, Gangwon-do, Korea. The age of every individual sample was estimated by the number of annual rings on the scales. A significant decrease of gonadosomatic index was noted between May and June reflecting the reproduction during this period. I. koreensis exhibited a strong bias to female (female : male, 1 : 0.56). The maximum age observed was 3 years old for male & female, both. The von Bertalanffy growth curves were expressed as $L_t=126.30[1-\exp\{-0.576(t+0.940)\}]$ for females and $L_t=100.19[1-\exp\{-1.119(t+0.695)\}]$ for males.Growth curve of weight was expressed as $W_t=11.567[1-\exp\{-0.576(t+0.940)\}]^{3.199}$ for females, $W_t=5.514[1-\exp\{-1.119(t+0.695)\}]^{3.199}$ for males. On the other hand, a significant difference in the growth rate between both sexes was found(i.e. females grew faster than males).

Optimum Concentration of Alizarin Complexone (ALC) for Otolith Marking of Pacific Cod Gadus macrocephalus (대구 Gadus macrocephalus 이석 표지를 위한 Alizarin Complexone의 최적 농도)

  • Kim, Tae Jin;Lee, So Gwang;Gwak, Woo Seok
    • Korean Journal of Ichthyology
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    • v.20 no.4
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    • pp.272-278
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    • 2008
  • Optimum concentration of alizarine complexone (ALC) for staining of otoliths for Pacific cod was determined by examination of stained quality, growth and survival rates. Small juveniles ($34.1{\pm}1.8mm$ TL, $mean{\pm}SD$) were immersed in four different concentrations (20, 40, 60, 80 mg/L) and large ones ($73.8{\pm}1.2mm$ TL, $mean{\pm}SD$) in five different concentrations (1, 5, 10, 20, 40 mg/L) of ALC for 24 hrs. The fish were then reared and observed for 14 days. The stained quality of otoliths was evaluated by dividing them into four grades by the presence of fluorescent stains on the otoliths under G-excited UV light. The small juveniles stained with the different ALC concentrations had 100% staining success, and their growth rate and body weight did not differ significantly between treatments. Optimal ALC concentration for the smaller juveniles was 20 mg/L in the present experiment. On the other hand, distinct fluorescent rings were confirmed on otoliths of larger juveniles in the 10 mg/L treatment with high survival rate. These results suggest that ALC staining at concentrations of 10 mg/L with larger juveniles will be helpful for release-recapture experiments for stock enhancement of Pacific cod.

Synthesis and Single-crystal Structure of Fully Dehydrated Fully Ca2+exchanged Zeolite Y (FAU), |Ca35.5|[Si121Al71O384]-FAU

  • Seo, Sung-Man;Choi, Sik-Young;Suh, Jeong-Min;Jung, Ki-Jin;Heo, Nam-Ho;Lim, Woo-Taik
    • Bulletin of the Korean Chemical Society
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    • v.30 no.8
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    • pp.1703-1710
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    • 2009
  • The single-crystal structure of |$Ca_{35.5}$|[$Si_{121}Al_{71}O_{384}$]-FAU, $Ca_{35.5}Si_{121}Al_{71}O_{384}$ per unit cell, a = 24.9020(10) $\AA$, dehydrated at 673 K and 2 ${\times}\;10^{-6}$Torr, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd$\overline{3}$m at 294 K. The large single crystals of zeolite Y (Si/Al = 1.70) were synthesized up to diameters of ${\mu}m\;and\;Ca^{2+}$-exchanged zeolite Y were prepared by ion exchange in a batch method of 0.05 M aqueous Ca($NO_3)_2$ for 4 hrs at 294 K. The structure was refined using all intensities to the final error indices (using only the 971 reflections for which $F_o\;>\;4{\sigma}(F_o))\;R_1$ = 0.038 (based on F) and $R_2$ = 0.172 (based on $F^2$). About 35.5 $Ca^{2+}$ ions per unit cell are found at an unusually large number of crystallographically distinct positions, four. Nearly filling site I (at the centers of the double 6-rings), 14.5 octahedrally coordinated $Ca^{2+}$ ions (Ca-O = 2.4194(24) $\AA$ and O-Ca-O = 87.00(8) and 93.00($8^o$) are found per unit cell. One $Ca^{2+}$ ion per unit cell is located at site II’ in the sodalite cavity and extends 0.50 $\AA$ into the sodalite cavity from its 3-oxygen plane (Ca-O = 2.324(13) $\AA$ and O-Ca-O = 115.5(10)o). The remaining twenty $Ca^{2+}$ ions are found at two nonequivalent sites II (in the supercages) with occupancies of 10 and 10 ions, respectively. Each of these $Ca^{2+}$ ions coordinates to three framework oxygens, either at 2.283(3) or 2.333(5) $\AA$, respectively, and extends either 0.24 or 0.54 $\AA$, respectively, into the supercage from the three oxygens to which it is bound. In this crystal, site I is the most populated; sites II’ and II are only sparsely occupied.$Ca^{2+}$+ appears to fit the octahedral site I best. No cations are found at sites III or III’, which are clearly less favorable for $Ca^{2+}$ ions in dehydrated zeolite Y.

A Survey on the Performance of Surgical Hand Scrubs (의사와 간호사의 외과적 손씻기에 관한 지식, 태도 및 실천에 대한 조사 연구)

  • 윤혜상
    • Journal of Korean Academy of Nursing
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    • v.26 no.3
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    • pp.591-604
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    • 1996
  • The surgical hand scrub (SHS) is the single most important procedure in the prevention of post-operative wound infections and yet it remains the most violated of all infection control procedures. The purpose of this study was to gain an overview of SHS habits in operative th atre personnel and to determine knowledge and attitudes to identify whether there is a need for improvement. The subjects for this study included 79 doctors and 94 nurses working in the operative th atres of four hospitals in Incheon City and Kyungki Province. Related data were collected from July 25 to August 10, 1995 by the author. The data were analyzed using descriptive stat-istics and Chi-squre test. The results of the study are summarized as follows : 1. Nurses felt that they conducted SHS for a longer period of time than doctors did(X=20.1, P=.005). 2. Nurses and doctors had some knowledge of slip-ping rings off fingers and the length of nails, but they lacked knowledge on the duration of SHS, handwashing after an operation and on manicure. 3. There were many reasons given for insufficient SHS included : 1) because they were so busy (38%). 2) brushes were too harsh(19.7%). 3) operations were very simple(18.7%). 4) surgical latex gloves provide functional barrier(11.6%). 5) SHSs were troublesome(7.4%) 6) there were no clocks near the sinks(2.5%) and 7) the operative patients were administered antibiotics after operartion(2.1%). 4. Most of nurses and doctors considered SHS to be important in prevention against post operative infections. 5. Nurses were found to do a thorough SHS, but residents were found to neglect SHS. 6. Considering prevention against postoperative infections, most nurses and doctors considered aseptic techniques, environment-sanitary management and SHS more important than the use of antibiotics, the resistance of patients or the method of operation. 7. Half of the nurses and doctors(54.3%) considered surgical latex gloves to function well as a barrier. 8. Half of the nurses (56.4%) and doctors(51.9%) learned SHS as part of the curriculum in their school education and the rest(nurses : 95.7%, doctors : 74.7%) learned SHS as part of their In Service Education. In conclusion, these findings suggest a need to develop an educational program on surgical hand scrub and hospital infection control for surgical personnels, to install clocks near the hand scrub sinks, to consider a violation report for negligent surgical hand scrubs, and to develop a soft brush for hand scrubs in order to increase performance of the surgical hand scrub.

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A Study on the Effect of Microwave Heating on Starch Food -1. The Physico-chemical Property of the Effect of Microwave Heating on Potato Starch and Purified Potato Starch- (Micro파(波) 가열(加熱)이 전분질(澱粉質) 식품(食品)에 미치는 영향(影響)에 관(關)한 연구(硏究) -1. Micro파(波) 가열이 감자전분(澱粉) 조성(組成)에 미치는 이화학적(理化學的) 성질(性質)에 관하여-)

  • Choi, Ock-Ja;Ko, Moo-Seok
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.13 no.3
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    • pp.268-274
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    • 1984
  • The purpose of this study was to investigate the physico-chemical effects of a potato starch and a purified potato starch under the condition of the microwave heating. They were exposed to the microwave energy in a 950 W, 2,450 MHz oven for 30 through 120 seconds. As the microwave heating time was increased, the contents of moisture and the crude fat of the samples were remarkably decreased irrespective of the starch composition, but on the other hand the contents of crude ash was slightly decreased and the crude protein was almost unchanged. The rings of crystallinity come to gradually changed in the X-ray diffraction pattern, and then the only 1 ring, of which interplanner spacing is wide, is changed strikingly. As the microwave heating time is increased, the starch granules which observed by a scanning electron microscope were broken partially with a special form, and the granules of purified potato starch were broken faster than those of potato starch. With the same condition that the microwave heating time was increased, while the gelatinization temperature comes to fall, the swelling power and the solubility were increased. Besides these, while the gelatinization temperature of the purified potato starch was lower than that of the potato starch, both the swelling power and the solubility of the purified potato starch is higher than those of the potato starch.

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Synthesis of Tellurium Sorption Complexes in Fully Dehydrated and Fully Ca2+-exchanged Zeolites A and X and their Single-crystal Structures

  • Lim, Woo-Taik;Park, Jong-Sam;Lee, Sang-Hoon;Jung, Ki-Jin;Heo, Nam-Ho
    • Bulletin of the Korean Chemical Society
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    • v.30 no.6
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    • pp.1274-1284
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    • 2009
  • Single crystals of fully dehydrated and fully $Ca^{2+}$-exchanged zeolites A (|$Ca_6$|[$Si_{12}Al_{12}O_{48}$]-LTA) and X (|$Ca_{46}$| [$Si_{100}Al_{92}O_{384}$]-FAU) were brought into contact with Te in fine pyrex capillaries at 623 K and 673 K, respectively, for 5 days. Crystal structures of Te-sorbed $Ca^{2+}$-exchanged zeolites A and X have been determined by single-crystal X-ray diffraction techniques at 294 K in the cubic space group Pm$\overline{3}$ m (a = 12.288(2) $\AA$) and Fd $\overline{3}$ (a = 25.012(1) $\AA$), respectively. The crystal structures of pale red-brown |$Ca_6Te_3$|[$Si_{12}Al_{12}O_{48}$]-LTA and black coloured |$Ca_{46}Te_8$| [$Si_{100}Al_{92}O_{384}$]-FAU have been refined to the final error indices of $R_1/wR_2\;=\;0.1096/0.2768\;and\;R_1/wR_2$ = 0.1054/ 0.2979 with 204 and 282 reflections for which $F_o\;>\;4{\sigma}(F_o)$, respectively. In the structure of |Ca6Te3|[$Si_{12}Al_{12}O_{48}$]- LTA, 6 $Ca^{2+}$ ions per unit cell were found at one crystallographic positions, on 3-fold axes equipoints of opposite 6-rings. In |$Ca_{46}Te_8$|[$Si_{100}Al_{92}O_{384}$]-FAU, 46 $Ca^{2+}$ ions per unit cell were found at four crystallographically distinct positions: 3 $Ca^{2+}$ ions at Ca(1) fill the 16 equivalent positions of site I, 21 $Ca^{2+}$ ions at Ca(2) fill the 32 equivalent positions of site I’, 10 and 12 $Ca^{2+}$ ions at Ca(3) and Ca(4), respectively, fill the 32 equivalent positions of site II. The Te clusters are stabilized by interaction with cations and framework oxygen. In sodalite units, Te-Te distances of 2.86(10) and 2.69(4) $\AA$ in zeolites A and X, respectively exhibited strong covalent properties due to their interaction with $Ca^{2+}$ ions. On the other hand, in large cavity and supercage, those of 2.99(3) and 2.76(11) $\AA$ in zeolites A and X, respectively, showed ionic properties because alternative ionic interaction was formed through framework oxygen at one end and $Ca^{2+}$ cations at the other end.