• 한국식품조리과학회지
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• 제9권1호
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• pp.43-51
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• 1993

Buckwheat protein isolate was tested for the effects of pH, addition of sodium chloride and heat treatment on solubility, emulsion capacities, emulsion stability, surface hydrophobicity, foam capacities and foam stability. The solubility of buckwheat protein isolate was affected by pH and showed the lowest value at pH 4.5, the isoelectric point of buckwheat protein isolate. The solubility significantly as the pH value reached closer to either ends of the pH, i.e., pH 1.0 and 11.0. The effects of NaCl concentration on solubility were as follows; at pH 2.0, the solubility significantly decreased when NaCl was added; at pH 4.5, it increased above 0.6 M; at pH 7.0 it increased; and at pH 9.0 it decreased. The solubility increased above $80^{\circ}C$, at all pH ranges. The emulsion capacity was the lowest at pH 4.5. It significantly increased as the pH approached higher acidic or alkalic regions. At pH 2.0, when NaCl was added, the emulsion capacity decreased, but it increased at pH 4.5 and showed the maximum value at pH 7.0 and 9.0 with 0.6 M and 0.8 M NaCl concentrations. Upon heating, the emulsion capacity decreased at acidic pH's but was maximised at pH 7.0 and 9.0 on $60^{\circ}C$ heat treatment. The emulsion stability was the lowest at pH 4.5 but increased with heat treatment. At acidic pH, the emulsion stability increased with the increase in NaCl concentration but decreased at pH 7.0 and 9.0. Generally, at other pH ranges, the emulsion stability was decreased with increased heating temperature. The surface hydrophobicity showed the highest value at pH 2.0 and the lowest value at pH 11.0. As NaCl concentrationed, the surface hydrophobicity decreased at acidic pH. The NaCl concentration had no significant effects on surface hydrophobicity at pH 7.0, 9.0 except for the highest value observed at 0.8 M and 0.4 M. At all pH ranges, the surface hydrophobicity was increased, when the temperature increased. The foam capacity decreased, with increased in pH value. At acidic pH, the foam capacity was decreased with the increased in NaCl concentration. The highest value was observed upon adding 0.2 M or 0.4 M NaCl at pH 7.0 and 9.0. Heat treatments of $60^{\circ}C$ and $40^{\circ}C$ showed the highest foam capacity values at pH 2.0 and 4.5, respectively. At pH 7.0 and 9.0, the foam capacity decreased with the increased in temperature. The foam stability was not significantly related to different pH values. The addition of 0.4 M NaCl at pH 2.0, 7.0 and 9.0 showed the highest stability and the addition of 1.0 M at pH 4.5 showed the lowest. The higher the heating temperature, the lower the foam stability at pH 2.0 and 9.0. However, the foam stability increased at pH 4.5 and 7.0 before reaching $80^{\circ}C$.

• 한국해양학회지
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• 제3권1호
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• pp.1-7
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• 1968

Two major processes that affect the vertical distribution of apparent pH in the Subarctic region of the Northeastern Pacific Ocean are (1) apparent oxygen utilization by marine organisms and (2) carbonate dissolution. Simplified mathematical approximations show that, in the pH ravge of 7.2 to 8.3, the utilization of 0.1 mM of oxygen (2.24 ml/liter) lowers the pH by 0.20 units and 0.1 mM of carbonate dissolution increases the pH by 0.25 units. Since Oxygen utilization exceeds 0.3 mM while the carbonate dissolution, with respect to the surface, is about 0.05mM, the effect of oxygen utilization is much greater than the dissolution effect of carbonate on the pH of seawater.

• 한국식품저장유통학회지
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• 제2권2호
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• pp.225-232
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• 1995

In order to study the effect of modified atmosphere packaging(M.A.P.) and controlled atmosphere(C. A.) storage on keeping freshness of mushrooms (Agricus-bisporus). Mushrooms was packaged with polyethylene(P.E.) film (40${\mu}{\textrm}{m}$, 60${\mu}{\textrm}{m}$, 80${\mu}{\textrm}{m}$) and C.A. conditions(CO2 concentration of 2%, O2 concentration of 2%) and storage at 0$\pm$1$^{\circ}C$, RH(relative hummidity) 92$\pm$1%. Gas composition in film was changed rapidly at early of storage, but it kept a constant level after 14 days of storage, and then kept at the level of 6~9% CO2 and 2~5% O2. Weight loss was 5% in non-packed mushrooms after 3 days of storage, but P.E. film, CO2 treated, C.A. conditions were 5% after 21 days of storage. Flesh firmness of the mushrooms was continuously decreased throughout storage period and the lowest of flesh firmness changed was 80${\mu}{\textrm}{m}$-P.E. film packing. Discoloration of the piteous of mushrooms appears to be the most Important factors to determine its marketability, L value of it appears to be of the high values at P.E. film packing and C.A. conditions during period. Large amount of ethanol and acetaldehyde were produced from the 7 days during storage, large contents of mannitol and trehalose were at the 14 days and 7 days during storage.

• 한국식생활문화학회지
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• 제5권4호
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• pp.443-448
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• 1990

The object of this study was to investigate the characteristics of pectinesterase(PE), polygalacturonase(PG) and Peroxidase(POD) in Kimchi materials. The results were as follows : 1. The specific activities of PEs in Korean cabbage, Korean raddish, garlic and ginger were 200 unit/mg protein, 23.1 unit/mg protein, 0.8 unit/mg protein and 32 unit/mg protein, respectively. The optimum pHs of PEs in all materials were between 7 to 8. The concentrations of NaCl, $CaCl_2$ which showed the highest activities of PEs were $0.2{\sim}0.3M$ NaCl, 50 mM $CaCl_2$ in Korean cabbage and raddish, 0.05 M NaCl, 20 mM $CaCl_2$ in garlic and 0.2 M NaCl, 20 mM $CaCl_2$ in ginger. 2. The specific activities and the optimum pHs of PGs were 1.5 unit/mg protein and pH 4.5 in Korean cabbage, 1.6 unit/mg protein and $pH\;4.5{\sim}5.5M$ in Korean raddish, 0.06 unit/mg protein and $pH\;3.0{\sim}3.5M$ in garlic, and 0.06 unit/mg protein and $CaCl_2$ in ginger. The concentrations of NaCl, $CaCl_2$ which showed the highest activities of PGs were $0.1{\sim}0.2M$ NaCl and $0.15{\sim}0.2mM$ mM $CaCl_2$ in all materials. 3. The specific activities and the optimum pHs of PODs in Korean cabbage, Korean raddish, garlic and ginger were 71.3 unit/mg protein ; pH 6.0. 769 unit/mg protein ; pH 5.5, 1.09 unit/mg protein ; pH 4.5 and 12.7 unit/mg protein ; $pH\;5.0{\sim}5.5M$, respectively. POD activities were not decreased in Korean cabbage, but decreased in Korean raddish by the increase of NaCl, $CaCl_2$ concentrations. In garlic and ginger, POD activities were a little slightly affected by the increase of NaCl, $CaCl_2$ concentrations.

• Annals of Clinical Neurophysiology
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• 제25권2호
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• pp.84-92
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• 2023

Background: Clinical spectrum of immunoglobulin M (IgM) monoclonal gammopathy varies from IgM monoclonal gammopathy of unknown significance (IgM-MGUS) to hematological malignancies. We evaluated the clinical features, electrophysiological characteristics, and prognosis of patients with peripheral neuropathy associated with IgM monoclonal gammopathy (PN-IgM MG). Methods: We retrospectively evaluated 25 patients with PN-IgM MG. Peripheral neuropathy was classified as axonal, demyelinating, or undetermined, based on electrophysiological studies. We classified the enrolled patients into the IgM-MGUS and malignancy groups, and compared the clinical and electrophysiological features between the groups. Results: Fifteen patients had IgM-MGUS and 10 had hematologic malignancies (Waldenström's macroglobulinemia: two and B-cell non-Hodgkin's lymphoma: eight). In the electrophysiological evaluation, the nerve conduction study (NCS) criteria for demyelination were met in 86.7% of the IgM-MGUS group and 10.0% of the malignancy group. In particular, the distal latencies of the motor NCS in the IgM-MGUS group were significantly prolonged compared to those in the malignancy group (median, 9.1 ± 5.1 [IgM-MGUS], 4.2 ± 1.3 [malignancy], p = 0.003; ulnar, 5.4 ± 1.9 [IgM-MGUS], 2.9 ± 0.9 [malignancy], p = 0.001; fibular, 9.3 ± 5.1 [IgM-MGUS], 3.8 ± 0.3 [malignancy], p = 0.01; P-posterior tibial, 8.3 ± 5.4 [IgM-MGUS], 4.4 ± 1.0 [malignancy], p = 0.04). Overall treatment responses were significantly worse in the malignancy group than in the IgM-MGUS group (p = 0.004), and the modified Rankin Scale score at the last visit was higher in the malignancy group than in the IgM-MGUS group (2.0 ± 1.1 [IgM-MGUS], 4.2 ± 1.7 [malignancy], p = 0.001), although there was no significant difference at the initial assessment. Conclusions: The risk of hematological malignancy should be carefully assessed in patients with PN-IgM MG without electrophysiological demyelination features.

• 대한수학회보
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• 제55권5호
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• pp.1441-1462
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• 2018

In this paper, we investigate the fractional p&q-Kirchhoff type system $$\{M_1([u]^p_{s,p})(-{\Delta})^s_pu+V_1(x){\mid}u{\mid}^{p-2}u\\{\hfill{10}}={\ell}k^{-1}F_u(x,\;u,\;v)+{\lambda}{\alpha}(x){\mid}u{\mid}^{m-2}u,\;x{\in}{\Omega}\\M_2([u]^q_{s,q})(-{\Delta})^s_qv+V_2(x){\mid}v{\mid}^{q-2}v\\{\hfill{10}}={\ell}k^{-1}F_v(x,u,v)+{\mu}{\alpha}(x){\mid}v{\mid}^{m-2}v,\;x{\in}{\Omega},\\u=v=0,\;x{\in}{\partial}{\Omega},$$ where ${\Omega}{\subset}{\mathbb{R}}^N$ is an unbounded domain with smooth boundary ${\partial}{\Omega}$, and $0<s<1<p{\leq}q$ and sq < N, ${\lambda},{\mu}>0$, $1<m{\leq}k<p^*_s$, ${\ell}{\in}R$, while $[u]^t_{s,t}$ denotes the Gagliardo semi-norm given in (1.2) below. $V_1(x)$, $V_2(x)$, $a(x):{\mathbb{R}}^N{\rightarrow}(0,\;{\infty})$ are three positive weights, $M_1$, $M_2$ are continuous and positive functions in ${\mathbb{R}}^+$. Using variational methods, we prove existence of infinitely many high-energy solutions for the above system.

• 대한간호학회지
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• 제23권2호
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• pp.284-298
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• 1993

This study was carried out to compare perceptions about nursing activities in oriental medical hospital settings. Data were collected from 47 patients hospitalized in an oriental medical hospital, and 41 nurses and 47 oriental medical doctors working in four oriental medical hospitals from July 10th to Sept.20th, 1991. The findings of this study are as follows. 1. There were significant differences in the perceptions about physical nursing activities between patients ( M=44.07) and nurses (M=48.44) (t=-3.09. p=0.003) , and between nurses and oriental medical doctors (M=41.47) (t=-5,20. p=0.000). 2. There were no differences in perceptions about psychological and emotional nursing activities between patients ( M=27.64) and nurses (M=28.52) (t=-1.02, p=0.310), but there were differences between nurses and oriental medical doctors ( M=24. 31) (t=-5.31, p=0.000). 3. There were differences in perceptions about observation, recording and implemention of medical care activities between patients (M=53.65) and nurses (M=57.08) (t=-2.15, p=0.034), but there were no differences between nurses and oriental medical doctors (M=57.28) (t=0.14, p=0.892). 4. There were no differences in perceptions about nursing management activities between patients (M=24.88) and nurses (M=26.42) (t=-1.91, p=0.059), but there were differences between nurses and oriental medical doctors (M=24.25) (t=-3.24, p=0.002).

• 한국미생물·생명공학회지
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• 제44권2호
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• pp.130-139
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• 2016

지렁이의 장내로부터 분리한 미생물 중에서 지질을 가수분해하는 활성이 높은 미생물을 선발하였으며, 동정하여 Aeromonas hydrophila PL43으로 명명하였다. A. hydrophila PL43이 생산하는 지질분해 효소의 정제는 황산암모늄 침전, DEAE-sepharose FF 이온교환 크로마토그래피, Sepharose S-300HR 겔 크로마토그래피 단계로 수행하였으며 최종적으로 정제한 지질분해 효소는 p-nitrophenyl butyrate (pNPB)를 기질로 사용했을 때, 84.5배로 정제되었고 효소 활성의 회수율은 3.7%이었다. p-nitrophenyl palmitate (pNPP)를 기질로 사용했을 때에는 56.6배로 정제되었고 효소 활성의 회수율은 2.5%이었다. SDS-PAGE를 수행한 결과, A. hydrophila PL43이 생산하는 지질분해효소의 분자량은 약 74 kDa으로 추정되었다. 지질분해 효소의 pH에 대한 영향은 pNPB와 pNPP 기질에서 pH 8.0에서 최대활성이 보였고 pH 7.0−10.0에서 안정하였다. pNPB를 기질로 사용한 경우에는 50℃에서 pNPP를 기질로 사용한 경우는 60℃에서 최대 활성을 나타냈으며, 정제한 지질분해 효소는 20−60℃에서 안정성을 나타내었다. 정제한 지질분해효소는 금속이온 Co²⁺, Cu²⁺, Fe²⁺에 의해서 효소활성이 억제되었으며, EDTA의 metal chelating에 의해 활성이 회복되었다. Inhibitor에 의한 저해는 효소 활성부위의 serine 잔기와 결합하여 효소 활성을 억제하는 PMSF에서 가장 우수하였으며 효소 활성부위의 aspatyl 잔기에 결합하여 효소활성을 억제하는 pepstatin A는 농도가 높아짐에 따라 효소활성을 저해하였다. 따라서 정제한 지질분해 효소는 활성부위에 serine 잔기와 aspartyl 잔기가 있는 것으로 사료되었다. 정제한 지질분해 효소의 K_m 값과 V_max 값은 pNPB를 기질로 사용 했을 때 K_m 값과 V_max 값은 1.07 mM과 7.27 mM/min이고, 기질이 pNPP일 때 K_m 값과 V_max 값은 1.43 mM 과 2.72 mM/min이었다.

• 미생물학회지
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• 제30권4호
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• pp.305-309
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• 1992

Bacillus stearothermophilus 의 cytosine deaminase (EC 3. 5. 4.1 )를 수율 52.7% 로 7.2배 부분정제했다. 부분정제된 cytosine deaminase 는 cytosine 을 유일한 기질로 이용하였으머 5-methylcytosine 과 5-fluorocytosine 은 기질고 이용되지 못햇으며 cytosine 에 대한 Michaelis 정수 Km 값은 5.9 mM 이었다. 본효소는 pH 4.0 에서 7.0 까지의 폭 넓은 pH 영역에서 안정했으며 80.deg.C 에서 10 분간 열처리하여도 75% 이상의 효소활성이 잔존하여 높은 내열성 효소였다. 본 효소의 반응최적 pH 는 7.0-7.5 였으며 반응 최적 온도는 35. 37.deg.C 였다. 그리고 Arrhenium plot 에 의하여 계산된 활성화 에너지 값(Ea value) 은 26 Kcal/mol 이었다. 본 효소는 중금속인 1 mM의 $Cd^{2+}$ , $Hg^{2+}$ 및 $Cu^{2+}$ 에 의하여 완정히 실활되었으며 GMP 와 CMP 에 의해서는 효소활성이 촉진되었다. 특히 본 효소는 p-chloromercuribenzoate 에 의하여 효소 활성이 강하게 저해되어 thiol 효소임을 추정할 수 있었다.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제23권2호
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• pp.201-201
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• 2016