• Title/Summary/Keyword: p-$\Delta$ effect

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Effect of Sintering Temperature on Electrical and Dielectric Behavior of Pr6O1-Based ZnO Varistors with DC Accelerated Aging Stress (Pr6O1계 ZnO 바리스터의 DC 가속열화 스트레스에 따른 전기적, 유전적 거동에 미치는 소결온도의 영향)

  • 남춘우;정영철;김향숙
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.3
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    • pp.244-252
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    • 2002
  • The electrical and dielectric behavior fort DC accelerated aging stress of P $r_{6}$ $O_{11}$-based Zno varistors cnsisting of ZnO-P $r_{6}$ $O_{11}$-CoO-C $r_2$ $O_3$-E $r_2$ $O_3$ were investigated with sintering temperature in the range of 1325~1345$^{\circ}C$. The varistor ceramics with increasing sintering temperature were more densified. A more densified varistors leaded to high stability for DC accelerated aging stress. Furthermore, the stability for DC accelerated aging stress was increased with the leakage current and dtan $\delta$/dV decreasing in order of 1325longrightarrow1335longrightarrow1345longrightarrow134$0^{\circ}C$ in sintering temperature. It was found that the stability for DC stress is affected more greatly by the leakage current and dtan $\delta$/dV than the densification. It is considered that the stability of varistors for DC stress can be estimated by considering the factors, such as the densification, leakage current, and dtan $\delta$/dV. As a result, the varistor sintered at 134$0^{\circ}C$ exhibited the highest stability, with %$\Delta$ $V_{lmA}$=-1.54%, %$\Delta$$\alpha$=-2.49%, %$\Delta$ $I_{\ell}$=+240.68%, 5%$\Delta$tan$\delta$=+29.96%.96%.96%.%.

Effect of Different Coagulants on Quality of Tofu Incorporated with Persimmon Fruit Powder (응고제 종류가 감 분말 첨가 두부의 품질과 저장성에 미치는 영향)

  • Lee, Yun-Rae;Chung, Hun-Sik;Seong, Jong-Hwan;Moon, Kwang-Deog
    • Food Science and Preservation
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    • v.18 no.5
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    • pp.678-683
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    • 2011
  • The effects of coagulant types (magnesium chloride, calcium chloride, calcium sulfate, glucono-${\delta}$-lactone) on yield, quality properties and storability of astringent persimmon powder added tofu were investigated. Yield, hardness, chewness, crispness, and overall acceptability of tofu coagulated by glucono-${\delta}$-lactone were higher than those coagulated by the others. L value, a value, pH, soaking-solution turbidity, and total aerobic bacteria of glucono-${\delta}$-lactone coagulated tofu were lower than those coagulated by the others. Calcium sulfate and calcium chloride coagulated tofu showed relatively high L and b values. Magnesium chloride coagulated tofu had higher sensory score for firmness, taste, overall acceptability than calcium chloride and calcium sulfate coagulated tofu, but there was no significant difference between magnesium chloride and glucono-${\delta}$-lactone. The results suggested that glucono-${\delta}$-lactone and magnesium chloride were found to be the suitable coagulants for processing of the persimmon powder added tofu.

A Study on the Effect of Moxibustion at Shinmun(H7) according to Cold or Heat Tendency (한열성향(寒熱性向)에 따른 신문혈(神門穴) 애구(艾灸) 효능(效能)의 비교(比較) 연구(硏究))

  • Kim, Dong-hoon;Kim, Jong-deog;Kim, Eun-jung;Kim, Kyung-tae;Rhu, Seong-ryong;Jung, Ji-chul;Park, Young-bae
    • Journal of Acupuncture Research
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    • v.21 no.4
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    • pp.135-147
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    • 2004
  • Objective: Moxibustion is one of major healing technique in oriental medicine. It has been widely used in many disease. There is an text which suggest moxibustion is more efficient to the situation of han(寒) and heo(虛) than yeal(熱) and sil(實) in Huangdineijing <黃帝內經>. The aim of this study is to research the effect of moxibustion at Shinmun(H7) is different according to cold or heat tendendy man by analyzing the electroencephalogram(EEG). Methods: We classified objects by their cold or heat tendency using questionnare for cold - heat patternization. (12 cold tendency man, 19 heat tendency man) Before and after moxibustion at Shinmun(H7), EEG raw data were measured during 5 minutes. The correlation dimension(D2), the correlation dimension variability rate(${\Delta}D2$), largest lyapunov exponent(L1) and largest lyapunov exponent variability rate(${\Delta}L1$) were calculated. We analyzed D2, ${\Delta}D2$, L1, ${\Delta}L1$ to see the effect of moxibustion at Shinmun(H7) was statistically different according to Cold or Heat tendendy man. Results : Paired t-test showed significant differences between before and after moxibustion at Shinmun(H7) on the Fp2 in D2(p<0.05), on the Fp2, F3 and F4 in ${\Delta}L1$(p<0.05). Student Hest showed significant differences between cold and heat tendendy man on the F3 in ${\Delta}L1$(p<0.05). Conclusion: These results suggest that moxibustion at Shinmun has an effect on stabilizing mind and it is more efficient to the cold tendendy man than the heat tendendy man.

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The Overexpression of Subtilisin Enzyme Using Mutations on Transition State Regulatory Proteins of AprE Promoter and Development of Bacillus subtilis Host System (AprE Promoter전이상태 조절인자 변이주를 이용한 공업적 효소의 과발현과 고초균 숙주계의 개발)

  • 류성호;박승환김병기
    • KSBB Journal
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    • v.11 no.1
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    • pp.8-14
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    • 1996
  • Bacillus subtillis strains with transition state regulator mutations and a spore mutation were developed for the overexpression of apsE and for the enhancement of expression level. Among the many regulator genes, degU and hpr were chosen as a representative positive and negative regulator for the aprE, respectively. Spo II G was used for the construction of asporogeneous strains. All the mutants were constructed from two protease-deleted strain DB104 and the apsE gene was transformed with an integration vector pMK101. DB104(deg$U^h$(32) $his^+$)::pMK101(Cm) and DB104($\Delta$her(Em))::pMKl01(Cm) show 7-fold and about 2-fold increase in aprE expression level, respectively. But the effect of transition state regulator mutation on the aprE expression was diminished when the integrated aprE gene was amplified by the high concentration of chloramphenicol, i. e. 30 $\mu\textrm{g}$/ml. DB104($\Delta$spoIIG(Pm) degUh(32) his+)::pMK101(Cm) and DB104($\Delta$spoIIG(Pm) $\Delta$hpr(Em))::pMK101 double mutant show 10-fold and 3-fold increase in aprE expression level, respectively. The results suggest that sporulation mutation and transition state regulator mutation have independent and additive effect on the aprE expression, and the same gene dosage effect on the transition state regulator mutation was also identified.

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The Effect of Freshwater Inflow on the Spatio-temporal Variation of water Qualify of Yeongil Bay (영일만 수질의 시ㆍ공간 변동에 미치는 담수유입의 효과)

  • 김영숙;김영섭
    • Korean Journal of Environmental Biology
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    • v.22 no.1
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    • pp.57-65
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    • 2004
  • In order to determine the effect of fresh water inflow from the Heongsan river on the changes of water quality in the Yeongil Bay (Korea), the seasonal changes of water temperature, salinity, chemical oxygen demand (COD), dissolved inorganic nitrogen(DIN) and phosphate phosphorus ($PO_4$-P) concentrations were examined using the data set obtained five fixed points of Yeongil Bay from 1998 to 2000. The distributions and changes of COD and concentrations of total inorganic phosphorous (TIP) and nitrogen (TIN) at three points Heongsan river, were also compared with those of Yeongil Bay. Based on the correlations of DIN and $PO_4$-P, it was found that the inflow of freshwater affected on the water quality of Yeongil Bay. Such a complicacy was confirmed by the prominent differences in n few water quality measures between Site 1(the innermost area) and Site 5 (the mouth of the bay). The negative correlations in $\Delta N/\Delta P $ at sites 1, 2 and 3 of the inner-part of the bay also indicated a large effect of freshwater inflow on the water quality of the bay. The extremely low atomic ratio of an average of 6.4 in $\Delta N/\Delta P $ compared to the Redfild ratio suggested that the DIN was depleted in the overall bay system. In contrast, it was inferred that the excessive PO$_4$-P concentration was due to the inflow of freshwater from the Heongsan river.

Thermochemical Behaviour of Some Salicylaldehyde G-P Complexes of Fe(Ⅲ), Co(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ)

  • Hafez, M.A.H.;Moussa, M.N.H.
    • Bulletin of the Korean Chemical Society
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    • v.13 no.3
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    • pp.334-336
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    • 1992
  • Through two different techniques TGA and DSC the thermal decomposition processes of salicyaldehyde G-P complexes having the general formula: $$[MCl_2(L)_2]^{2+}$2Cl^-$; where L = salicyaldehyde carbohydrazone pyridinum cation, and M= Fe(III), Co(II), Cu(II) and Zn(II), have been studied. From the obtained thermogravimetric curves the following parameters n, $E_{\alpha}$, A, ${\Delta}S^{\neq}$, ${\Delta}H^{\neq}$ and ${\Delta}G^{\neq}$ were evaluated. The effect of the nature of the metal ions present in the complexes studied upon the calculated thermodynamic parameters was reported. A suitable mechanism for the thermal decomposition process was suggested.

Convergence Study on Remineralization Effect of fTCP and CPP-ACP using QLF-D (QLF-D를 이용한 fTCP와 CPP-ACP의 재광화 효과에 관한 융합 연구)

  • Kang, Yong-Ju;Lee, Su-Young
    • Journal of the Korea Convergence Society
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    • v.7 no.6
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    • pp.133-139
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    • 2016
  • This study was to evaluate the change of mineral loss of fTCP and CPP-ACP in artificial caries lesions using QLF-D to compare the remineralization effect of recently developed fTCP and CPP-ACP, which is widely used as a remineralization cream in current dental clinics. Bovine specimens used in this study formed the artificial caries lesion immersing in demineralization solution for 10 days and were divided randomly into the following two groups; Group 1- Tooth Mousse containing 10% CPP-ACP, Group 2- Clinpro Tooth Creme containing 950ppm NaF and fTCP. Two tooth paste were applied to the artificial caries lesion of specimens and they were immersed in artificial saliva for 1 week. Mineral loss of artificial caries lesion was evaluated by fluorescence loss (${\Delta}F$) values using QLF-D. QLF-D analysis showed that the ${\Delta}F$ and ${\Delta}Fmax$ value increased 2.65 and 6.63, respectively, in the Tooth Mousse group, and the mineral loss decreased statistically significantly(p<0.05). However, Clinpro Tooth Creme group had no statistically significant difference. ${\Delta}Fmax$ value of Tooth Mousse group was statistically significant difference compared to the Clinpro Tooth Creme. Therefore, the Tooth Mousse containing 10% CPP-ACP is more effective than Clinpro Tooth Creme containing fTCP in the treatment of remineralization of artificial caries lesions.

Characterization of the Wild-Type and Truncated Forms of a Neutral GH10 Xylanase from Coprinus cinereus: Roles of C-Terminal Basic Amino Acid-Rich Extension in Its SDS Resistance, Thermostability, and Activity

  • Hu, Hang;Chen, Kaixiang;Li, Lulu;Long, Liangkun;Ding, Shaojun
    • Journal of Microbiology and Biotechnology
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    • v.27 no.4
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    • pp.775-784
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    • 2017
  • A neutral xylanase (CcXyn) was identified from Coprinus cinereus. It has a single GH10 catalytic domain with a basic amino acid-rich extension (PVRRK) at the C-terminus. In this study, the wild-type (CcXyn) and C-terminus-truncated xylanase ($CcXyn-{\Delta}5C$) were heterologously expressed in Pichia pastoris and their characteristics were comparatively analyzed with aims to examine the effect of this extension on the enzyme function. The circular dichorism analysis indicated that both enzymes in general had a similar structure, but $CcXyn-{\Delta}5C$ contained less ${\alpha}-helices$ (42.9%) and more random coil contents (35.5%) than CcXyn (47.0% and 32.8%, respectively). Both enzymes had the same pH (7.0) and temperature ($45^{\circ}C$) optima, and similar substrate specificity on different xylans. They all hydrolyzed beechwood xylan primarily to xylobiose and xylotriose. The amounts of xylobiose and xylotriose accounted for 91.5% and 92.2% (w/w) of total xylooligosaccharides (XOS) generated from beechwood by CcXyn and $CcXyn-{\Delta}5C$, respectively. However, truncation of the C-terminal 5-amino-acids extension significantly improved the thermostability, SDS resistance, and pH stability at pH 6.0-9.0. Furthermore, $CcXyn-{\Delta}5C$ exhibited a much lower $K_m$ value than CcXyn (0.27 mg/ml vs 0.83 mg/ml), and therefore, the catalytic efficiency of $CcXyn-{\Delta}5C$ was 2.4-times higher than that of CcXyn. These properties make $CcXyn-{\Delta}5C$ a good model for the structure-function study of $({\alpha}/{\beta})_8$-barrel-folded enzymes and a promising candidate for various applications, especially in the detergent industry and XOS production.

Effect of Overcorrection (-)Lens on Stereo-acuity and Angle of Deviation in Intermittent Exotropia (간헐외사시에서 과교정 (-)렌즈가 입체시 및 사시각에 미치는 영향)

  • Kim, Young Cheong;Park, Sang Woo
    • Journal of Korean Ophthalmic Optics Society
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    • v.18 no.3
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    • pp.305-311
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    • 2013
  • Purpose: This study was conducted to evaluate the effect of prescription of overcorrection (-) lens, which is the one of the non-surgical treatments, on stereo-acuity and angle of deviation in intermittent exotropia. Methods: Twenty four children with intermittent exotropia were enrolled from October 2011 to December 2011. The angle of deviation(${\Delta}$), stereo-acuity (arcsec), monocular and binocular visual acuity (BVA, LogMAR), control of exodeviation and fusional ability using Worth 4 dot test were evaluated at near (33 cm) and far (6 m), under the overcorrecting (-)lens of -1.00, -.00, and -.00 D. Results: As a baseline finding, the angle of exodeviation was $20.9{\pm}9.7$ at near and $23.0{\pm}7.5$ at far. The angle of exodeviation at near decreased to $18.5{\pm}10.0$ (p<0.01), $15.8{\pm}9.0$ (p<0.01), $14.0{\pm}9.1$ (p<0.01) compared with baseline angle of exodeviation at near, as increasing diopters of (-) lens from -.00 D, -2.00 D and -.00 D, respectively. The angle of exodeviation at far also decreased to $21.4{\pm}5.2$ (p=0.01), $19.6{\pm}6.3$ (p<0.01) compared with baseline, as increasing minus lens from -2.00 D and -3.00 D, respectively. However, BVA, control of exodeviation, fusional ability and stereo-acuity showed no significant decrease despite of increasing diopters of (-)lens. Conclusions: The prescription of overcorrection (-)lens is an effective therapeutic method in intermittent exotropia which can reduce the near and far angle of exodeviation, and binocular visual acuity and stereo-acuity maintained without significant decrease despite of application of overcorrection (-)lens.

How Does Yoga Breathing Affect Prefrontal QEEG Quotients?

  • Kim, Eunmi
    • Science of Emotion and Sensibility
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    • v.16 no.1
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    • pp.75-84
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    • 2013
  • The underlying changes in biological processes that are associated with reported changes in mental and physical health in response to yoga breathing ($pr{\bar{a}}n{\bar{a}}y{\bar{a}}ma$) have not been systematically explored yet. In this study, the effects of a yoga breathing program on prefrontal EEG were tested with middle-aged women. Participants were collected as volunteers and controlled into two groups. Two channel EEG was recorded in the prefrontal region (Fp1, Fp2) from the yoga breathing group (n=17) and control group (n=17). QEEG quotients were transformed from the EEGs and analyzed by the ANOVAs on gain scores. As a result, ${\alpha}/{\delta}$ (left, right) and CQ (correlation quotient) for yoga breathing participants were significantly decreased compared to control group (p<.05). ${\alpha}/{\beta}_H+{\alpha}/{\delta}$ (left, right) were increased significantly (p<.05). For those significantly changed QEEG quotients, the interaction effects of Group x prefrontal alpha (${\alpha}$) and beta (${\beta}$) asymmetry were tested. Only the ${\alpha}$ asymmetry showed main effect on the gain score of ${\alpha}/{\beta}_H+{\alpha}/{\delta}$ (right) with F (1, 34)=5.694 (p<.05). Pearson's correlation coefficient between ${\alpha}$ asymmetry and gain score of ${\alpha}/{\beta}_H+{\alpha}/{\delta}$ (right) was .374 (p<.05). The gain score of ${\alpha}/{\beta}_H+{\alpha}/{\delta}$ (right) was increased for the right ${\alpha}$ dominance of yoga breathing group. On the contrary it was decreased for the left ${\alpha}$ dominance of yoga breathing group as well as the control regardless of the dominance. The result of this study implies that yoga breathing increases stress resistance and is effective in the management of physical stress. Emotionally relaxed people may have greater instantaneous stress reduction after yoga breathing. Moreover, yoga breathing could be also beneficial for depressed who may be more vulnerable to stress.

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