• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1070-1083
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• 2015

A gene (GT-SM3B) encoding a thermostable secreted oligoendopeptidase (GT-SM3B) was cloned from the thermophile Geobacillus thermoleovorans DSM 15325. GT-SM3B is 1,857 bp in length and encodes a single-domain protein of 618 amino acids with a 23-residue signal peptide having a calculated mass of 67.7 kDa after signal cleavage. The deduced amino acid sequence of GT-SM3B contains a conservative zinc metallopeptidase motif (His⁴⁰⁰-Glu⁴⁰¹-X-XHis⁴⁰⁴). The described oligopeptidase belongs to the M3B subfamily of metallopeptidases and displays the highest amino acid sequence identity (40.3%) to the oligopeptidase PepF_Ba from mesophilic Bacillus amyloliquefaciens 23-7A among the characterized oligopeptidases. Secretory production of GT-SM3B was used, exploiting successful oligopeptidase signal peptide recognition by Escherichia coli BL21 (DE3). The recombinant enzyme was purified from the culture fluid. Homodimerization of GT-SM3B was determined by SDS-PAGE. Both the homodimer and monomer were catalytically active within a pH range of 5.0–8.0, at pH 7.3 and 40℃, showing the K_m, V_max, and k_cat values for carbobenzoxy-Gly-Pro-Gly-Gly-Pro-Ala-OH peptidolysis to be 2.17 ± 0.04 × 10^-6 M, 2.65 ± 0.03 × 10^-3 µM/min, and 5.99 ± 0.07 s^-1, respectively. Peptidase remained stable at a broad pH range of 5.0–8.0. GT-SM3B was thermoactive, demonstrating 84% and 64% of maximum activity at 50℃ and 60℃, respectively. The recombinant oligopeptidase is one of the most thermostable M3B peptidase, retaining 71% residual activity after incubation at 60℃ for 1 h. GT-SM3B was shown to hydrolyze a collagenous peptide mixture derived from various types of collagen, but less preferentially than synthetic hexapeptide. This study is the first report on an extracellular thermostable metallo-oligopeptidase.

• Analytical Science and Technology
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• v.12 no.1
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• pp.28-33
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• 1999

Glutathione(GSH) in biological samples was determined by high performance liquid chromatographic(HPLC) method with fluorescence detector(FLD) after monobromobimane(MBB) or 4-fluoro-7-sulfobenzofurazan(SBD-F) derivatization. The detection limit of $0.03{\mu}g/mL$ was obtained after MBB derivatization, derivative of MBB was about 200 times more sensitive than that of SBD-F. N-acetylcysteine was used as internal standard and tetrabutylammonium ion as counter ion for better separation. The determination by ion-pairing chromatography after MBB derivatization was characterized by linearity in the range between $0.08{\sim}8.33{\mu}g/mL$ with a good correlation coefficient of 0.998. By precision test appeared relative standard deviation at less than 5% at three different concentrations. This method can be used for the analysis of GSH in plasma and tissue.

• Wind and Structures
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• v.11 no.4
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• pp.275-289
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• 2008

Large eddy simulations have been performed within and over different types of urban building arrays. This paper adopted three dimensionless parameters, building frontal area density (${\lambda}_f$) the variation degree of building height (${\sigma}_h$), and the staggered degree of building range ($r_s$), to study the systematic influence of building spacing, height and layout on wind and turbulent characteristics. The following results have been achieved: (1) As ${\lambda}_f$ decrease from 0.25 to 0.18, the mean flow patterns transfer from "skimming" flow to "wake interference" flow, and as ${\lambda}_f$ decrease from 0.06 to 0.04, the mean flow patterns transfer from "wake interference" flow to "isolated roughness" flow. With increasing ${\lambda}_f$, wind velocity within arrays increases, and the vortexes in front of low buildings would break, even disappear, whereas the vortexes in front of tall buildings would strengthen and expand. Tall buildings have greater disturbance on wind than low buildings do. (2) All the wind velocity profiles and the upstream profile converge at the height of 2.5H approximately. The decay of wind velocity within the building canopy was in positive correlation with ${\lambda}_f$ and $r_s$. If the height of building arrays is variable, Macdonald's wind velocity model should be modified through introducing ${\sigma}_h$, because wind velocity decreases at the upper layers of the canopy and increases at the lower layers of the canopy. (3) The maximum of turbulence kinetic energy (TKE) always locates at 1.2 times as high as the buildings. TKE within the canopy decreases with increasing ${\lambda}_f$ and $r_s$ but the maximum of TKE are very close though ${\sigma}_h$ varies. (4) Wind velocity profile follows the logarithmic law approximately above the building canopy. The Zero-plane displacement $z_d$ heighten with increasing ${\lambda}_f$, whereas the maximum of and Roughness length $z_0$ occurs when ${\lambda}_f$ is about 0.14. $z_d$ and $z_0$ heighten linearly with ${\sigma}_h$ and $r_s$, If ${\sigma}_h$ is large enough, $z_d$ may become higher than the average height of buildings.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.1
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• pp.96-107
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• 2001

An unsteady numerical simulation was performed to analyze flow structures behind a local suction/blowing in a flat-plate turbulent boundary layer. The local forcing was given to the boundary layer flow by means of sinusoidally oscillating jet. A version of the unsteady $\kappa$-$\xi$-f(sub)u model (Rhee and Sung 2000) was employed. The Reynolds number based on the momentum thickness was about Re(sub)$\theta$=1700. The forcing frequency was varied in the range 0.011$\leq$f(sup)+$\leq$0.044 with a fixed forcing amplitude A(sub)o=0.4. The predicted results were compared and validated with the experimental data. It was shown that the unsteady locally-forced boundary layer flow is predicted well by the $\kappa$-$\xi$-f(sub)u model. The effect of the pitch angle of local forcing on the reduction of skin friction was also examined.

• Phonetics and Speech Sciences
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• v.11 no.4
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• pp.63-70
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• 2019

This study investigated individual variability of L2 learners' categorical judgments of L2 stops by exploring English learners' perceptual processing of two acoustic cues (voice onset time [VOT] and f0) and working memory capacity as sources of variation. As prior research has reported that English speakers' greater use of the redundant cue f0 was responsible for gradient processing of native stops, we examined whether the same processing characteristics would be observed in L2 learners' perception of Korean stops (/t/-/t^h/). 22 English learners of L2 Korean with a range of L2 proficiency participated in a visual analogue scaling task and demonstrated variable manners of judging the L2 Korean stops: Some were more gradient than others in performing the task. Correlation analysis revealed that L2 learners' categorical responses were modestly related to individuals' utilizations of a primary cue for the stop contrast (VOT for L1 English stops and f0 for L2 Korean stops), and were also related to better working memory capacity. Together, the current experimental evidence demonstrates adult L2 learners' top-down processing of stop consonants where linguistic and cognitive resources are devoted to a process of determining abstract phonemic identity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.1
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• pp.120-139
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• 1996

Experiment was performed to study the heat transfer characteristics in 27 kinds of 15 : 1 scale models of multi-louverred fin heat exchangers with a wide range of variables(R $e_{Lp}$ =100~1, 800, $L_p$/F$p$=0.3~0.9, $\theta$=20$^{\circ}$~40$^{\circ}$). Thermofoil heaters were used to heat the louver fins and the local average Nusselt number for each louver in the louver array was obtained at constant wall temperature conditions. Correlations are developed to predict the heat transfer characteristics and drag coefficients. Generally, the heat transfer characteristics in the multi-louvered fins is shown to be similar to those of the laminar heat transfer on a flat plate. As the Reynolds number, the louver pitch to fin pitch ratio$L_p$/F$p$and the louver angle($\theta$) increase respectively, the average Nusselt number increases, but the variation of average Nusselt number as a function of the louver angle is smaller than that as a function of the louver pitch to fin pitch ratio. In case of$L_p$/F$p$ <0.5, the average Nusselt number of the 3rd louver is especially lower than the others, it is expected that it is due to the flow structure such as a recirculation flow and a flow separation.

• Phonetics and Speech Sciences
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• v.15 no.3
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• pp.1-7
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• 2023

This study investigates how the phonological and phonetic information of vowels influences prosodic prominence among linguistically untrained listeners using public speech in American English. We first examined the speech material's phonetic realization of vowels (i.e., maximum F0, F0 range, phone rate [as a measure of duration considering the speech rate of the utterance], and mean intensity). Results showed that the high vowels /i/ and /u/ likely had the highest max F0, while the low vowels /æ/ and /ɑ/ tended to have the highest mean intensity. Both high and low vowels had similarly high phone rates. Next, we examined the effects of the vowels' phonological and phonetic information on listeners' perceptions of prosodic prominence. The results showed that vowels significantly affected the likelihood of perceived prominence independent of acoustic cues. The high and low vowels affected probability of perceived prominence less than the mid vowels /ɛ/ and /ʌ/, although the former two were more likely to be phonetically enhanced in the speech than the latter. Overall, these results suggest that perceptions of prosodic prominence in English are not directly influenced by signal-driven factors (i.e., vowels' acoustic information) but are mediated by expectation-driven factors (e.g., vowels' phonological information).

• Archives of design research
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• v.16 no.2
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• pp.415-424
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• 2003

People store information not only in their Drain but also material things. Norman called it knowledge in the world. The general way to store the information is to paste labels. 4 burner gas range force user to make conceptual model between burner and switch to see labels. but those are cognitive stress. Norman suggested spatial analogies for natural mapping between display and control. However the way of his methods in spatial analogies was not compatible with kitchen atmosphere. To solve those problems 1 suggested color coding . This study hypothesized that the mapping between burner and switch is realized by color coding. To testy the hypothesis 1 compared A group using general gas range with B group using color coded gas range. The result showed difference between A and B in accuracy ( F (1, 38) = 17.892, p < 0.01) and response time ( F (1, 38) = 6.726 p < 0.05). The result of this test is to certify that color coding affect peoples by presenting the difference accuracy and response time. As result this study presents that color coding can be compatible the product having importance to certify in the design process.

• Research in Community and Public Health Nursing
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• v.8 no.2
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• pp.262-276
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• 1997

This study evaluates the relationship between health belief. self-efficacy and exercise and diet compliance in coronary heart disease patients. The study subjects were 96 CHD patients who visited the outpatient clinic at 3 general hospitals in Taegu city from April 3, 1997 to May 3, 1997. Data was collected by the researcher and two registered nurses who work at a cardiac outpatient clinic. Face-to-face interview was conducted. Moon's health belief scale(l990) and Hicky and others' Cardiac Diet Self-Efficacy Instrument (CDSEI, 1992), Cardiac Exercise Self-Efficacy Instrument (CESEI, 1992) were used. The instrument developed by the researcher based on the reference review was used to measure exercise and diet compliance. The data were analyzed by using descriptive statistics, Pearson correlation coefficient, t-test, ANOVA, Tukey verification and Stepwise multiple regression with the SAS program. The results of this study were as follows; 1. The degree of health belief(score range: 1-4) perceived benefit: 3.06 barrier: 2.04 severity: 2.93 2. The degree of self-efficacy(score range: 1-5) exercise self-efficacy: 2.91 diet self-efficacy: 3.32 3. The degree of compliance (score range: 1-4) exercise compliance: 2.34 diet compliance: 2.95 4. The exercise compliance had a positive correlation with perceived benefit(r=0.5327, p=0. 0001), severity(r=0.2780, p=0.0061), exercise self-efficacy(r=0.6675, p=0.0001), and a negative correlation with barrier{r= -0.4236, p=0.0001). The diet compliance had a positive correlation with perceived benefit (r=0.6439, p=0.0001), severity(r=0.4244, p=0.0001), diet self-efficacy(r=0.6629, p=0.0001), and a negative correlation with barrier{r= -0.5098, p=0.0001). 5. According to pt's education level, (F=3.02, p=0.0336), received massage from mass media on exercise and diet(t=3.81, p=0.0002), presence of cardiac patients in the family members or friends(t=2.00, p=0.0478), created significant differences in exercise compliance. According to occuption(F=3.03, p=0.0215), hospitalized experience(t=4.59, p=0.0000), presence of chest pain(t=3.63, p=0.0005), there was also a significant difference in diet compliance. 6. The combination of exercise self-efficacy, perceived benefit and pt's education level explained 50.18% of the variance in exercise compliance. The combination of diet self-efficacy, perceived benefit and barrier explained 56.76% of the variance in diet compliance. On the basis of the above findings, the follow ing recommendations are suggested: 1. To promote the exercise. diet compliance for CHD patients, a well organized health teaching and nursing intervention program should be developed. 2. More research is needed to investigate other variables affecting exercise and diet compliance of CHD patients. 3. To promote self-efficacy and a positive health belief in CHD patients, a well organized and an approachable nursing intervention program should be developed. 4. Factors other than diet. exercise compliance should be evaluated to discover the impact on CHD patients.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.3
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• pp.423-431
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• 2002

An experimental study is conducted to investigate the effect of two-frequency forcing on turbulent flow behind a backward-facing step at the Reynolds number of 27000 based on the step height. The forcing is provided from a thin slit located at the edge of the backward-facing step to increase mixing behind the backward-facing step and consequently to reduce the reattachment length. With single frequency forcing, the minimum reattachment length is obtained at the non-dimensional forcing frequency (F) of St$\_$h/ = 0.29. With two-frequency forcing, a subharmonic frequency (F/2) or biharmonic frequency (2F) is combined with the fundamental frequency (F), i.e. (F, F/2) or (F, 2F) forcing is applied. In the case of (F, F/2) forcing, the reattachment length is not much sensitive to the phase difference between F and F/2. However, the reattachment length significantly depends on the phase difference between F and 2F in the case of (F, 2F) forcing. At a certain range of the phase difference, the reattachment length becomes smaller than that of the single frequency forcing.