• 한국식품영양학회지
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• 제16권4호
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• pp.379-387
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• 2003

동결건조 녹용을 물과 단백질 가수분해 효소로 추출하였다. 동결건조녹용을 물추출하는 경우, 추출효율은 5% 농도로 5$0^{\circ}C$에서 6시간 추출하는 것이 가장 높았다. 추출물을 HPLC 분석한 결과, 물추출액에 존재하던 고분자 단백질은 단백질 가수분해 효소에 의해 저분자화되었다. 저분자화율은 세균 protease를 사용한 경우가 가장 높고 다음 pepsin인데, papain의 효과는 적었다. 생녹용에 단백질 가수분해 효소를 5시간 작용시켜서 얻은 추출액의 추출율은 세균 protease는 33.4% (280nm의 흡광도 13.25), papain은 22.4%(흡광도 10.06), pepsin은 30.2%(흡광도 11.34)였다. 30분 동안 끓인 녹용에 단백질 가수분해 효소를 5시간 작용시킨 용액의 추출율은 세균 protease는 47.6%(흡광도 12.54), papain은 26.4%(흡광도 7.48), pepsin은 45.6%(흡광도 7.23)였다. 단백질함량은 물추출액은 52.1%, 세균 protease 추출액은 37.8%였고, 아미노산 함량은 물추출액은 16.3%, 세균 protease 추출액은 31.9%였다. 회분함량은 물추출액은 8.8%, 세균 protease 추출액은 5.6%였다. 무기물 함량은 물추출액의 경우 Ca 3.6%, P 8.6%, Mg0.01%, Na 1.4%, F 0.02%, 세균 pretense의 경우 Ca 2.5%, P 11.8%, Mg 0.046%, Na 2.1%, F 0.018%였다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1210-1218
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• 2000

Four experiments were conducted to evaluate the effect of temperature and humidity on biochemical indices of Arbor Acres broilers at different weeks of age. The alkaline phosphatase (AKP), acid phosphatase (ACP), lactic dehydrogenase (LD), creatine kinase (CK), plasma glucose (Glu), calcium (Ca), potassium (K), chloride (Cl), urea nitrogen (UN), uric acid (UA), plasma thyroxin (T4), triiodothyronine (T3) and insulin levels were determined in all the four experiments. In experiment 1, the plasma Glu, LD and CK levels were increased by heat exposure ($35{^{\circ}C}$ and 35, 60, or 85% RH, 2 h) and this effect was aggravated by longer exposure (24 h). No significant changes (p>0.05) were found in Ca concentration, activity of AKP and ACP. In experiment 2, temperature (10, 20, 30, $33{^{\circ}C}$) had significant effect on the levels of K, Cl, UN, UA levels and the activity of LD (p<0.01), but had no significant influence on the activity of CK (p>0.05). The UN, UK and LD levels were elevated by low temperature $(10{^{\circ}C})$ (p<0.01), Cl content was increased by high temperature ($(33{^{\circ}C})$ (p<0.01), and K level was decreased by high ($(33{^{\circ}C})$ or low $(10{^{\circ}C})$ temperature and increased by medium temperature $(30{^{\circ}C})$ (p<0.01). The humidity (35, 85% RH) only had significant effect on Cl concentration which was decreased by high humidity (p<0.01). In experiment 3, the result showed that only the LD and CK activity were significantly increased (p<0.01) by high temperature (7, 24, 28, $32{^{\circ}C}$) or high humidity (35, 85% RH). Temperature and humidity had no significant effect on K, Cl, UA, UN and Glu levels (p>0.05). In experiment 4 (24, 27, 30, $33{^{\circ}C}$; 30, 45, 60, 75, 90% RH), plasma T3 level was declined by high temperature $(33{^{\circ}C})$, and this phenomena disappeared in birds under high temperature and high humidity environment. T4 concentration in plasma was not affected by temperature (p>0.05), but was increased by high or low humidity (p<0.01). Neither temperature nor humidity had significant effect on plasma insulin concentration (p>0.05). The results of the four experiments suggested that broilers at different growth periods might have different thermal requirements and would response differently to heat exposure. The plasma biochemical indices themselves had big variation; the reaction of the indices to thermal exposure treatment differed with the age of broilers. The big variation of biochemical indices themselves might cover the response of indices to temperature and humidity treatments.

• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.353-360
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• 1998

A bacterial strain PN33 producing large amounts of extracellular pectin lyase (PNL, EC 4.2.2.10) was isolated from soil. The isolated bacterium was identified as a strain of Bacillus sp. Production of PNL by the strain was induced only by pectins, with a higher degree of esterification, which had been added to the culture medium as a sole carbon source. The optimal medium for PNL production was determined to consist of 10 g pectin, 2 g yeast extract, 4 g $K_2HPO_4{\cdot}3H_2O$, 0.6 g $MgSO_4$, and 0.11 g $CaCl_2$ per liter (pH 7.0). The PNL activity in the culture supernatant reached the highest level of 132 mU/ml after 32 h cultivation at $37^{\circ}C$ in the optimal medium. The PNL produced was purified to homogeneity by ammonium sulfate fractionation (50~80%), and cation exchange and size exclusion chromatographies. The molecular mass of the enzyme was estimated to be approximately 52 kDa by SDS-PAGE. Almost the same mass was determined by nondenaturing PAGE, indicating that the functional enzyme had a monomeric structure. As expected, the PNL exhibited higher activities on the highly esterified pectins whereas it gave no detectable activity on polygalacturonic acid. The enzyme showed the highest activity at the acidic pH of 6.0, exceptional for a bacterial PNL. Maximum activity was measured at $40^{\circ}C$, although the stability f the purified enzyme was poor at this temperature. alcium (1 mM) was found to activate the PNL activity by $50\%$, and also remarkably increased the thermal stability f the enzyme. Phenylmethylsulfonylfluoride (PMSF) and iethylpyrocarbonate (DEPC) inhibited the PNL activity lmost completely at the concentration of 5 mM. This result ndicates that some serine and histidine residues of the nzyme may play an essential role for catalytic function of he enzyme.

• Bulletin of the Korean Chemical Society
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• 제15권1호
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• pp.33-36
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• 1994

The x values of nonstoichiometric chemical formula, $Tb_4O_{7-{\delta}}\;or\;TbO_{1.5+x}$, have been determined in temperature range from 600$^{\circ}$C to 1000$^{\circ}$C under oxygen partial pressure of 2 ${\times}$ 10$^{-1}$ to 1 ${\times}$ 10$^{-5}$ atm by using quartz microbalance. The x values varied from 0.0478 to 0.1964 in the above conditions. The enthalpy of formation for x' in TbO$_{1.5+(0.25-xo-x')}$, ${\delta}H_f$, was 4.93-3.40 kcal mol$^{-1}$ and the oxygen partial pressure dependence was -1/8.80∼-1/11.8 under these conditions. The electrical conductivity of the $TbO_{1.5+x}$ was measured under the same conditions and the values varied from about 10$^{-3}$ to 10$^{-6}\;{\Omega}^{-1}cm^{-1}$ within semiconductor range. The activation energies for the conduction increase with oxygen partial pressure from 0.83 to 0.89 eV under the above conditions. The l/n values obtained from the oxygen pressure dependence of the conductivity are 1/4.4-1/5.2. The conduction mechanism, defect structure, and other physical properties of the oxides are dicussed with the x values, the electrical conductivity values, and the thermodynamic data.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.926-933
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• 2012

일반적으로 비료용 인산은 황산과 인광석의 분해반응에 의해 생산되는데 이 반응은 발열반응으로써 온도가 상승하게 되면 생산수율 저하의 문제점이 따른다. 이를 해결하기 위해 인산제조공정에서는 불산(HF)과 사불화규소(SiF4)가 함유된 증기(vapor, $80^{\circ}C$)를 배출시키는 진공냉각기(vacuum cooler)를 운영하고 있으나, 이 과정에서 냉매 및 폴리실리콘 원료로 활용가능한 귀중한 자원(불소 & 규소)들이 버려지고 있다. 본 연구는 인산제조공정 부산물인 규불산(H2SiF6)으로 회수하기 위한 기초 실험연구로서, 불소회수 후 인산슬러리 내 불소 농도변화를 분석하여 규불산 회수가능량을 예측하였다. 회수 후 불소농도는 약 0.12wt% 감소하였고, 대상 비료공장의 생산규모를 고려할 경우 불소 회수가능량은 약 5,509 톤/년이었다. 한편 현장에서, 규불산의 농도는 0.35wt%에서 7.33wt%까지 농축되었고, 진공냉각기로부터 배출되는 증기유량은 $51,000m^3/hr$이었다. 또한 Pilot실험을 통한 불소 회수효율은 76.74%로 나타나, 실제 회수할 수 있는 규불산량은 5,340 톤/년으로 추정되었다.

• Journal of Korean Biological Nursing Science
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• 제18권1호
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• pp.43-50
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• 2016

Purpose: This study aimed to identify the relationship among knowledge, attitudes and prevention behaviors (PB) on tuberculosis (Tb) infection in nursing students. Methods: 268 subjects were recruited from two universities located in C D cities of Korea and data were collected utilizing self-reported questionnaires. Results: The mean scores of knowledge, attitudes and PB on Tb infection were 64.83, 3.18 and 2.97. The knowledge differed according to gender (t=-3.16, p=.002), grades (F=32.19, p<.001), educational experience about Tb (EETb) (F=10.59, p<.001), learning information about Tb (t=3.08, p=.002) and getting Tb: self or others (t=2.78, p=.006). The attitudes differed according to grades (F=7.71, p<.001) and EETb (F=2.68, p=.047). The PB differed according to grades (F=7.02, p<.001) and EETb (F=4.55, p=.004). Significant correlations were found between knowledge and PB (r=.20, p=001), attitudes and PB (r=.33, p<.001). The most significant factor influencing PB was attitudes with R2 value of 13.9% (F=11.81, p<.001). Conclusion: These findings indicate that knowledge and attitude adjustment may be necessary to improve PB for Tb infection in nursing students. Moreover further study is necessary to find out the ways to reinforce the level of attitudes. The results of the study can be utilized in educational programs for preventing Tb infection in nursing students.

• Applied Science and Convergence Technology
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• 제26권4호
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• pp.70-73
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• 2017

The dielectric constant and loss of poling/non-poling was measured in the $Pb_{1-3x/2}La_x[(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ samples. The addition of $La^{3+}$ to the $Pb_{1-3x/2}La_x[(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ did not cause a large change in grain size. But the addition of $La^{3+}$ did show transition temperature, which shifted toward low temperature in the $Pb[(Mg_{1/3}Ta_{2/3})Zr]O_3$ systems. In addition, the dielectric and pyroelectric properties (${\varepsilon}{\sim}20000$, $p{\sim}0.03C/m^2K$) of this system using $La^{3+}$ have been greatly improved. Pyroelectrics $Pb_{0.97}La_{0.02}(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ system was found to have a relatively high ferroelectric FOMs ($F_V{\sim}0.035m^2/C$, $F_D{\sim}0.52{\times}10^{-4}Pa^{-1/2}$) at room temperature. Spontaneous polarization showed a value of $0.27{\sim}0.35C/m^2$ in the composition added to $La^{3+}$. The piezoelectric constant ($d_{33}=350{\sim}490pC/N$) and electromechanical coupling factor ($k_P=0.25{\sim}0.35$) are obtained in $Pb_{1-3x/2}La_x[(Mg_{1/3}Ta_{2/3})_{0.66}Zr_{0.34}]O_3$ compositions with $La^{3+}$ dopant.

• 대한치과의사협회지
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• 제10권12호
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• pp.831-834
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• 1972

The authors have measured and analyzed the values of Point C from roentgenocephalograms of Korean adults, 51 males and 53 females, with normal occlusion. The results were as follows. 1. The position of Point C was -4.73mm. in male and -4.74mm. in female. 2. In samples of harmonious maxillary and mandibular basal bones, the position of Point C was -4.02mm. in male, while that was -5.33mm. in female, respectively. 3. When N.F.-M.P.A. was become larger, the position of Point C was moved more upward; while M.R.P. was increased larger, it was moved more downward. 4. The position of Point C was depended on the distance form the cross point with nasal floor and mandibular plane to the points A and B.

• 한국어류학회지
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• 제33권1호
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• pp.1-7
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• 2021

본 연구는 우리나라 서해의 모래와 암반 조간대에 서식하는 별망둑 Chaenogobius gulosus 후각기관의 해부 및 조직학적 구조를 확인하고 그 특징을 동소종(미끈망둑 Luciogobius guttatus, 날개망둑 Favonigobius gymnauchen)들과 비교하였다. 별망둑은 튜브형 전비공, 표면과 평행하는 후비공, 세로배열의 한 개 후판, 두 개 비낭, 후상피 하부에 풍부한 림프구, 호산구, 후감각뉴런에서 후돌기 직경의 1/4의 섬모 길이의 일반적 결과를 보여 주었다. 이러한 특징들 중 1) 0.5~1.0 mm의 전비공 직경, 0.2~0.5 mm의 후비공 직경(vs. 미끈망둑의 0.2~0.3 mm, 0.2~0.3 mm; 날개망둑의 0.2~0.4 mm, 0.1~0.3 mm의 전비공과 후비공 직경), 2) 감각상피에서의 상대적으로 풍부한 림프구, 3) 비감각섬모의 부재(vs. 미끈망둑에서 높은 분포; 날개망둑에서 낮은 분포), 4) 후감각뉴런의 후돌기 대비 1/4의 섬모 길이(vs. 미끈망둑의 1/4에서 1 : 1 비율 혼재; 날개망둑의 2~3배)는 두 동소종들과 비교되는 특이적인 결과였다. 결론적으로, 별망둑 후각기관의 해부 및 조직학적 특징들은 모래와 암반 조간대에서 다른 동소종들 보다 더 적극적인 면역반응과 활동적인 움직임에 적응된 결과로 간주된다.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1470-1474
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• 2012

The pharmacokinetics of prunasin after oral administration of amygdalin or a decoction of peach seeds was determined and compared in rats. A $C_{18}$ column was used for separation at a column temperature of $25^{\circ}C$. The mobile phase consisted of 20% aqueous acetonitrile, and the flow rate was 0.5 mL/min. After oral administration of a decoction of peach seeds, prunasin was absorbed rapidly, reaching a maximum plasma concentration ($C_{max}$) of 62.1 mg/L within 45 min. After oral administration of amygdalin, the absorption of prunasin was delayed. The $C_{max}$ of prunasin was 42.9 mg/L and was reached at 60 min. Values for the pharmacokinetic parameters of prunasin, including $T_{max}$, $C_{max}$, AUC, $T_{1/2}$, CL/F, and V1/F, were significantly different for the oral administration of amygdalin compared with that of a decoction of peach seeds.