• Journal of Advanced Marine Engineering and Technology
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• 제23권2호
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• pp.192-200
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• 1999

This paper describes experimental investigations of helium-air exchange flow through parti-tioned opening. Such exchange flow may occur following rupture accident of stand pipe in high temperature gas cooled reactor. A test vessel with a opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. Flow measurements are made with partitioned opening for parti-tion rations $H_p/H_1$ in the range 0 to 1 where $H_p$ and $H_1$ are partition length and height of the open-ing respecticely. In the case of $H_p/H_1$ of 0 flow passages of upward flow of the helium and down-ward flow of the air within the opening are unseparated (bidirectional) and the two flows interact exchange flow rate is minimum through range of the partition ratios, Two flow zones i.e. separat-ed(unidirectional)flow zone and unseparated(bidirectional) flow zone exist with increasing the partition. length, The exchange flow rate increases with increasing the separated flow zone. It is found that a maximum exchange flow rate exists at $H_p/H_1$ of 1. As a result fo comparison of the exchange flow rates by changing the partition ration the fluids interaction in the unseparated zone is found to be an important factor on the helium-air exchange flow rate.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.211-216
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• 2003

The objective of this study was to determine the degradability of cassava chip (CC), cassava waste (CW), yellow sweet potato (YP), white sweet potato (WP), purple sweet potato (PP), corn meal (CM), and rice bran (RB) using in situ technique. Two ruminally fistulated steers with an average weight of $303{\pm}10kg$ were used to determine in situ degradabilities of DM and OM. Seven feed sources were weighted in nylon bags ($38{\mu}m$ pore size) and incubated ruminally for 1, 2, 4, 6, 8, 12, 24, and 48 h. The results showed that asymptote (a+b) and effective degradability (ED) of DM of energy sources ranked from the highest to the lowest; CC, YP, WP, PP, RB, CW, and CM (99.3, 92.5; 97.6, 87.9; 97.5, 87.9; 97.2, 87.8; 87.5, 63.6; 78.6, 63.0 and 81.7; 59.3, respectively) and for OM asymptote (a+b) and effective degradability (ED) were similar to those of degradation of DM (99.4, 93.4; 98.8, 89.8; 98.5, 89.4; 98.4, 88.1; 92.4, 65.8; 85.1, 66.9 and 83.6, 63.3, respectively). It was concluded that disappearance characteristic of CC was the highest and it may potentially facilitate the achievement of optimal ruminal availability of energy: protein especially with NPN for microbial protein synthesis.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권4호
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• pp.344-350
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• 2006

Thermoplasma acidophilum is a thermoacidophilic archaeon that grows optimally at $59^{\circ}C$ and pH 2. Along with another thermoacidophilic archaeon, Sulfolobus solfataricus, it is known to metabolize glucose by the non-phosphorylated Entner-Doudoroff (nED) pathway. In the course of these studies, the specific activities of glyceraldehyde dehydrogenase and glycerate kinase, two enzymes that are involved in the downstream part of the nED pathway, were found to be much higher in T. acidophilum than in S. solfataricus. To characterize glycerate kinase, the enzyme was purified to homogeneity from T. acidophilum cell extracts. The N-terminal sequence of the purified enzyme was in exact agreement with that of Ta0453m in the genome database, with the removal of the initiator methionine. Furthermore, the enzyme was a monomer with a molecular weight of 49kDa and followed Michaelis-Menten kinetics with $K_m$ values of 0.56 and 0.32mM for DL-glycerate and ATP, respectively. The enzyme also exhibited excellent thermal stability at $70^{\circ}C$. Of the seven sugars and four phosphate donors tested, only DL-glycerate and ATP were utilized by glycerate kinase as substrates. In addition, a coupled enzyme assay indicated that 2-phosphoglycerate was produced as a product. When divalent metal ions, such as $Mn^{2+},\;CO^{2+},\;Ni^{2+},\;Zn^{2+},\;Ca^{2+},\;and\;Sr^{2+}$, were substituted for $Mg^{2+}$ the enzyme activities were less than 10% of that obtained in the presence of $Mg^{2+}$. The amino acid sequence of T. acidophilum glycerate kinase showed no similarity with E. coli glycerate kinases, which belong to the first glycerate kinase family. This is the first report on the biochemical characterization of an enzyme which belongs to a member of the second glycerate kinase family.

• 한국초지조사료학회지
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• 제20권4호
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• pp.295-302
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• 2000

The quality of the rice straw silage added with apple pomace was investigated in this study and the amount of apple pomace added in different treatments were 0, 20, 40 and 60%, respectively. Crude protein contents (6.4-7.5%) of rice straw silage added with apple pomace were significantly (P<0.05) higher than that of 100%. rice straw silage (5.3%), however, crude ash contents were lower (P<0.05) in supplementation of apple pomace. The trends of changing chemical composition between raw materials and end products of silages particularly in the contents of crude protein and crude ash were more apparent in the silages added with apple pomace by 40-60%. Values of pH and the contents of lactic acid and total acid in 40-60% apple pomace added silages were 3.9-4.1, 1.0- 1.5% and 2.7-4.5%, respectively which were significantly (P<0.05) higher than those of 4.6, 0.02% and 0.34% in 100% rice straw silage, respectively. In situ dry matter (DM) and neutral detergent fiber (NDF) disappearance rates in the rumen in the treatments of 40- 60% apple pomace added silages were significantly (P<0.05) higher than those of 100% rice straw silage particularly since after 3 and 24 hour incubation on DM and NDF disappearance, respectively. Although quickly degraded fraction (a) among the treatments were not significantly different, 28.4-28.5% of slowly degraded fraction (b) and 27.2-27.4% of effective degradability (ED, k=0.08) for DM were significantly (P<0.05) higher than those of 100% rice straw silage (12.5 and 24.6% respectively). NDF was in the same trend as in DM. 31.6-63.2% of NDF for b fraction and 18.7- 19.4% for ED in 40-60% apple pomace added silages were significantly (P<0.05) higher than those of 100% rice straw silage (12.4 and 17.6% respectively). (Key words : Rice straw silage, Apple pomace, Lactic acid, In situ digestibility, Effective degradability)

• Archives of Pharmacal Research
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• 제27권2호
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• pp.151-155
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• 2004

In our previous studies for the development of new anticonvulsant of broad spectrum, we found that N-cbz-$\alpha$-aminoglutarimides showed significant anticonvulsant activities of broad spectrum enough to be recommended for the new anticonvulsants and their anticonvulsant activities were dependent on their imide substituent groups. Based on these results, various N-cbz--$\alpha$-amino-N-alkoxyglutarimides, where the imide N-H was substituted with the hydroxy and alkoxy group, were prepared and evaluated for their anticonvulsant activities using the Maximal electroshock seizure (MES) and Pentylenetetrazole induced seizure (PTZ) tests and also the rotorod test. A series of (R) or (S)-N-cbz--$\alpha$-amino-N-alkoxyglutarimides could be prepared from the corresponding (R) or (S)-N-cbz-glutamic acid following the usual synthetic procedure. Among them, (R)-N-cbz--$\alpha$-amino-N-hydroxyglutarimide ($ED_{50}$=86.25 mg/kg) was most active in the MES test. In the case of the PTZ test, (R)-N-cbz--$\alpha$-amino-N-benzyloxyglutarimide ($ED_{50}$= 62.5 mg/kg) was most active. Among the tested compounds, 2a-c, 3a, and 3b showed anticonvulsant activities in the MES and PTZ test. All of the tested compounds, except 2f and 3f, showed significant anticonvulsant activities in the MES or PTZ test. In addition, the neurotoxicities of these compounds were comparable to other anticonvulsant drugs.

• Archives of Pharmacal Research
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• 제22권2호
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• pp.157-164
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• 1999

LB50016 was characterized as a selective and potent$ 5-HT_{1A}$ receptor agonist and evaluate it anxiolytic and antidepressant activities. It shows high affinity for $ 5-HT_{1A}$receptor, moderate affinity for $\alpha$2 adrenergic and $ 5-HT_{2A}$receptors and no significant affinity for other receptors tested. Hypothermia and increased serum corticosterone level were observed in LB50016-treated rats, which are mediated mostly by post synaptic $ 5-HT_{1A}$ receptor activation. In the mouse forced swim model for depression, LB50016-elicited dose-dependent reductions in immobility time, showing $ED_{50}$ of approximately 3 mg/kg i.p., which was blocked by pretreatment of NAN-190, $ 5-HT_{1A}$antagonist. In face-to-face test for anxiolytic activity in mice, estimated $ED_{50}$ was 2 mg/kg, i.p.. In isolation-induced aggression test with mice, fifty-fold increases in latency to attack were observed at 30 min and last up to 4 h after LB50016 treatment (3 mg/kg, i.p.). Taken together, LB50016-induced pharmacological activities are mediated by activation of $ 5-HT_{1A}$receptors, offering an effective therapeutic candidate in the management of anxiety and depression in humans.

• Journal of Trauma and Injury
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• 제31권3호
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• pp.135-142
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• 2018

Purpose: When hemodynamically unstable patients with blunt major trauma arrive at the emergency department (ED), the safety of performing early whole-body computed tomography (WBCT) is concerning. Some clinicians perform central venous catheterization (CVC) before WBCT (pre-computed tomography [CT] group) for hemodynamic stabilization. However, as no study has reported the factors affecting this decision, we compared clinical characteristics and outcomes of the pre- and post-CT groups and determined factors affecting this decision. Methods: This retrospective study included 70 hemodynamically unstable patients with chest or/and abdominal blunt injury who underwent WBCT and CVC between March 2013 and November 2017. Results: Univariate analysis revealed that the injury severity score, intubation, pulse pressure, focused assessment with sonography in trauma positivity score, and pH were different between the pre-CT (34 patients, 48.6%) and post-CT (all, p<0.05) groups. Multivariate analysis revealed that injury severity score (ISS) and intubation were factors affecting the decision to perform CVC before CT (p=0.003 and p=0.043). Regarding clinical outcomes, the interval from ED arrival to CT (p=0.011) and definite bleeding control (p=0.038), and hospital and intensive care unit lengths of stay (p=0.018 and p=0.053) were longer in the pre-CT group than in the post-CT group. Although not significant, the pre-CT group had lower survival rates at 24 hours and 28 days than the post-CT group (p=0.168 and p=0.226). Conclusions: Clinicians have a tendency to perform CVC before CT in patients with blunt major trauma and high ISS and intubation.

• 자원리싸이클링
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• 제7권1호
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• pp.50-56
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• 1998

분말도 2.0mm이하인 전로슬래그는 토양산도 중화능이 $CaCO_3$의 1/3수준이지만 Ca와 Mg를 함유하고 있어 CaMgCO$_3$를 대체할 수 있는 토양산도 중화제이며 이의 liming 효과는 속효성이면서 지속적이었다. 우리나라 일반 농경지 토양을 작물생육의 적정 토양산도인 pH 6.5로 개량하기 위한 전로슬래그 시용량은 $7~8{Mgha}^{-1}$이었다. 농경지 토양에 전로슬래그를 시용하였을 때 토양 pH 상승과 Ca, Mg, P, Fe, Si 함량이 유의적으로 증가하였으며 전로 슬래그 처리구에서 재배한 벼의 엽조직체내에는 Ca, P, Fe, Si 함량이 그리고 콩 조직체내에는 P 함량이 대조구에서 보다 높았다. 수량 증가효과는 전로슬래그 $8{Mgha}^{-1}$시용시 벼와 콩 모두 가장 높았으며 증수율은 간척지답에서 14.2%, 추락답에서 6.9%, 그리고 보통답에서는 4.3%이었으며 콩의 경우에는 36.6%로 벼 증수율보다 훨씬 높았다.

• Korean Chemical Engineering Research
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• 제47권6호
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• pp.788-794
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• 2009

황화수소 및 메틸머캡탄($CH_3SH$) 또는 DMS($CH_3SCH_3$)와 같은 황화합물들의 악취를 효율적으로 처리하기 위하여 축분으로 오염된 토양으로부터 sodium thiosulfate 또는 유리황과 같은 기질을 이용하여 미생물의 분리 및 동정을 하고 분리된 미생물들의 여러 가지 pH, 배양온도, 산소조건, 기질(황화합물) 농도, 질소원 및 탄소원의 농도 및 배양기 교반속도 등의 배양조건 하에서의 배양특성을 관찰하고 적정배양조건을 구축하였다. KD-1212와 DAH-1056 균주의 최적 pH는 각각 7.0 및 4.0이었으며 최적배양온도는 $30{\sim}35^{\circ}C$ 범위였다. 또한 독립영양미생물인 ED-1138 균주를 다른 오염된 토양에서 분리하였다. 균주를 고정한 바이오필터의 악취처리에 있어서 균주 DAH-1056이 기존 균주 Thiobacillus sp. IW보다 황화수소 제거능이 우수하였다. KD-1212 균주를 이용하여 황화합물의 농도 및 질소원 및 탄소원에 대한 성장특성을 조사한 결과, KD-1212는 sodium thiosulfate의 25 mM 농도에서 성장이 가장 잘되었고, 탄소원으로는 glucose와 maltose를 잘 이용하는 것으로 나타났다. 그리고 질소원으로는 yeast extract를 잘 이용하였으며 0.5% 농도에서 성장이 가장 잘 되었다.

• 대한임상독성학회지
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• 제18권2호
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• pp.110-115
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• 2020

Purpose: Acute kidney injury (AKI) in patients with glyphosate poisoning has a poor prognosis. This study aimed to predict the risk factors for AKI in patients with glyphosate poisoning at the emergency department (ED). Methods: Clinical data on glyphosate poisoning patients at ED who were older than 18 years were collected retrospectively between January 2013 and December 2019. The clinical characteristics and clinical outcomes of the AKI group in patients with glyphosate poisoning were compared with the non-AKI (NAKI) group. Results: Of 63 glyphosate poisoning patients, AKI was observed in 15 (23.8%). The AKI patients group showed the following: old age (p=0.038), low systolic blood pressure (p=0.021), large amount of ingestion (p=0.026), delayed hospital visits (p=0.009), high white blood cells (WBC) (p<0.001), high neutrophil counts (p<0.001), high neutrophil-lymphocyte (LN) ratios (p<0.001), high serum potassium (p=0.005), low arterial blood pH (p=0.015), and low pO2 (p=0.021), low bicarbonate (p=0.009), and high Poisoning Severity Score (PSS) (p<0.001). AKI patients required hemodialysis, ventilator care (p<0.001, p=0.002), and inotropics (p<0.001). They also showed more intensive care unit admission (p<0.001), longer hospitalization (p<0.001), and high mortality (p<0.001). Logistic multivariate regression analysis showed that high WBCs (OR, 1.223) and increased LN ratios (OR, 1.414) were independently associated with the occurrence of AKI. Conclusion: In patients with glyphosate poisoning at ED, high WBCs and increased LN ratios can help predict the occurrence of AKI.