• Restorative Dentistry and Endodontics
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• v.34 no.2
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• pp.145-153
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• 2009

The purpose of this study was to evaluate the effect of instrument compliance on the polymerization shrinkage stress measurements of dental composites. The contraction strain and stress of composites during light curing were measured by a custom made stress-strain analyzer, which consisted of a displacement sensor, a cantilever load cell and a negative feedback mechanism. The instrument can measure the polymerization stress by two modes: with compliance mode in which the instrument compliance is allowed, or without compliance mode in which the instrument compliance is not allowed. A flowable (Filtek Flow: FF) and two universal hybrid (Z100: Z1 and Z250: Z2) composites were studied. A silane treated metal rod with a diameter of 3.0 mm was fixed at free end of the load cell, and other metal rod was fixed on the base plate. Composite of 1.0 mm thickness was placed between the two rods and light cured. The axial shrinkage strain and stress of the composite were recorded for 10 minutes during polymerization. and the tensile modulus of the materials was also determined with the instrument. The statistical analysis was conducted by ANOVA. paired t-test and Tukey's test (${\alpha}<0.05$). There were significant differences between the two measurement modes and among materials. With compliance mode, the contraction stress of FF was the highest: 3.11 (0.13). followed by Z1: 2.91 (0.10) and Z2: 1.94 (0.09) MPa. When the instrument compliance is not allowed, the contraction stress of Z1 was the highest: 17.08 (0.89), followed by FF: 10.11 (0.29) and Z2: 9.46 (1.63) MPa. The tensile modulus for Z1, Z2 and FF was 2.31 (0.18), 2.05 (0.20), 1.41 (0.11) GPa, respectively. With compliance mode. the measured stress correlated with the axial shrinkage strain of composite: while without compliance the elastic modulus of materials played a significant role in the stress measurement.

• Journal of Microbiology
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• v.45 no.2
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• pp.158-167
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• 2007

In this study, we have cloned a novel cDNA encoding for a papain-family cysteine protease from the Uni-ZAP XR cDNA library of the polychaete, Periserrula leucophryna. This gene was expressed in Escherichia coli using the T7 promoter system, and the protease was characterized after partial purification. First, the partial DNA fragment (498 bp) was amplified from the total RNA via RT-PCR using degenerated primers derived from the conserved region of cysteine protease. The full-length cDNA of cysteine protease (PLCP) was prepared via the screening of the Uni-ZAP XR cDNA library using the $^{32}P-labeled$ partial DNA fragment. As a result, the PLCP gene was determined to consist of a 2591 bp nucleotide sequence (CDS: 173-1024 bp) which encodes for a 283-amino acid polypeptide, which is itself composed of an 59-residue signal sequence, a 6-residue propeptide, a 218-residue mature protein, and a long 3'-noncoding region encompassing 1564 bp. The predicted molecular weights of the preproprotein and the mature protein were calculated as 31.8 kDa and 25 kDa, respectively. The results of sequence analysis and alignment revealed a significant degree of sequence similarity with other eukaryotic cysteine proteases, including the conserved catalytic triad of the $Cys^{90},\;His^{226},\;and\;Asn^{250}$ residues which characterize the C1 family of papain-like cysteine protease. The nucleotide and amino acid sequences of the novel gene were deposited into the GenBank database under the accession numbers, AY390282 and AAR27011, respectively. The results of Northern blot analysis revealed the 2.5 kb size of the transcript and ubiquitous expression throughout the entirety of the body, head, gut, and skin, which suggested that the PLCP may be grouped within the cathepsin F-like proteases. The region encoding for the mature form of the protease was then subcloned into the pT7-7 expression vector following PCR amplification using the designed primers, including the initiation and termination codons. The recombinant cysteine proteases were generated in a range of 6.3 % to 12.5 % of the total cell proteins in the E. coli BL21(DE3) strain for 8 transformants. The results of SDS-PAGE and Western blot analysis indicated that a cysteine protease of approximately 25 kDa (mature form) was generated. The optimal pH and temperature of the enzyme were determined to be approximately 9.5 and $35^{\circ}C$, respectively, thereby indicating that the cysteine protease is a member of the alkaline protease group. The evaluation of substrate specificity indicated that the purified protease was more active towards Arg-X or Lys-X and did not efficiently cleave the substrates with non-polar amino acids at the P1 site. The PLCP evidenced fibrinolytic activity on the plasminogen-free fibrin plate test.

• Journal of the Korean Wood Science and Technology
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• v.44 no.1
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• pp.113-123
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• 2016

This study was to investigate the antifungal activity of A. holophylla essential oil against dermatophytes, such as Epidermophyton floccosum, Trichophyton mentagrophytes and Trichophyton rubrum, and to determine the potential effective compound as dermatitis treatment. To evaluate the potential antifungal activities of A. holophylla essential oil and its fractions, paper disc diffusion and agar dilution method tested with morphological observation. Also, their major constituents were analyzed by GC/MS. To determine synergic effects of active ingredient from A. holophylla essential oil were carried out by checkerboard microtiter plate testing. The morphological changes of the dermatophytes exposed to active fraction G4 were observed by electron microscopes. As the results, the highest activities were identified in the fraction containing ${\alpha}$-bisabolol. A mixture of ${\alpha}$-bisabolol and bornyl acetate showed the synergy effects, expressing high potential effects. Also, morphological observation using electron microscopes showed a dramatic changes of cell membrane of E. floccosum and T. rubrum exposed to fraction G4 containing ${\alpha}$-bisabolol. In conclusion, A. holophylla essential oil and its constituents were expected to be used as antifungal agent or raw material for dermatitis therapy.

• Korean Journal of Cleft Lip And Palate
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• v.2 no.1_2
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• pp.5-14
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• 1999

The aim of treatment of cleft lip and palate is to correct the cleft and associated problems surgically and thus hide the anomaly so that patients can lead normal lives. This correction involves surgically producing a face that does not attract attention, a vocal apparatus that permits intelligible speech, and a dentition that allows optimal function and esthetics. In neonatal periods, gross distortion of tissues surrounding the cleft requires considerable effort and time due to post operative functional defect and scarring and induces milk feeding problem, malocclusion of deciduous or permanent dentition, congenital missing teeth, skeletal dysplasia. The occurrence of a cleft deformity is a source of considerable shock to the parents of an afflicted baby, and the most appropriate approach is very important things. Thus we tried to analysis of dental arch, shape and size of deformity in cleft patients. The results were obtained as follows. 1. When the cast measurements of UCLP subjects at first visit it was found that the mean length was 9.29mm at the alveolar cleft width, also that was 11.7mm at the anterior width and 14mm at the posterior cleft width. 2. Comparison of UCLP group at first visit and just lip surgery, it was found that the older group showed a insignificant reduction in the width of the cleft in the alveolar, canine, and tuberosity regions. 3. The maxillary casts of the UCLP group at 6 months differ Significantly from those of the at 3 months in both length and width. but there was no statistical difference except anterior ridge length of nonclefted site. 4. Comparison at 6 months and 18 months, there was a greater change in length of the alveolar cleft width, intercanine width, and anterior cleft width. Maxillary arch became wider at both the canine region and intertuberosity region. also posterior anteroposterior length was increased but anterior AP length was decreased from 8.1mm to 7.7mm. There was meaningful increase at intertuberosity length; however, a significant reduction in width t-t'

• Journal of Aquaculture
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• v.18 no.1
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• pp.52-59
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• 2005

The productivity of cyclopoid copepod, Apocyclops royi fed by various diets (Isochrysis galbana, Tetraselmis suecica, Phaeodactylum tricornutum, concentrated freshwater Chlorella and baker's yeast) was investigated at tile different temperatures ($16-36^{\circ}C$) with different salinities (5-34 ppt). A. royi was cultured in 6 ml vessels (12 wells culture plate). Total production (188 inds.) and daily production (13.4 inds.) of nauplii by A. royi female at $32^{\circ}C$ were significantly higher than those of nauplii at the different temperatures (P<0.05). Development time from nauplii to copepodite and from nauplii to adult tended to increase with increasing water temperature up to 32. And total production (169 inds.) and daily production (9 inds.) of nauplii by A. royi female at 10 ppt were significantly higher than those of nauplii at the different salinities (P<0.05). The fastest development time from nauplii to copepodite and from nauplii to adult was observed at 10 ppt and 15 ppt, respectively (P<0.05). The highest total production of A. royi nauplii and fastest development time from nauplii to adult were obtained in females fed Isochrysis galbana (P<0.05). These results may indicate that the optimum culture temperature and salinity for A. royi are $32^{\circ}C$ and 10 ppt, respectively, and Isochrysis galbana is one of the suitable diets for this copepod.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.5
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• pp.323-334
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• 2020

Since boundary layer transition has a significant impact on the aero-thermodynamic performance of hypersonic flight vehicles, capability of accurate prediction of transition location is essential for design and performance analysis. In this study, γ-Re_θt model is improved to predict transition of hypersonic boundary layers and validated. A coefficient in the production term of the intermittency transport equation that affects the transition onset location is constructed and applied as a function of Mach number, wall temperature, and freestream stagnation temperature based on the similarity numerical solution of compressible boundary layer. To take into account a Mach number dependency of transition onset momentum thickness Reynolds number and transition length, additional correlation equations are determined as function of Mach number and applied to Re_θc and F_length correlations of the baseline model. The suggested model is implemented to a commercial CFD code in consideration of practical use. Analysis of hypersonic flat plate and circular cone boundary layers is carried out by using the model for validation purpose. An improvement of prediction capability with respect to variation of Mach number and unit Reynolds number is identified from the comparison with experimental data.

• Journal of fish pathology
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• v.6 no.1
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• pp.1-10
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• 1993

Two vibrio sp. strains were isolated from disease catfish(silurus asotus). The present isolates were identified as Vibrio ordalii based on their biological and biochemical characteristics ; they were positive for acid production from glucose, Iactose, maltose, sucrose and salicine, while negative for arabinose, galactose, inocitol and xylose. They are named KL-1 and KL-2, KL-1 and KL-2 strains were similar to physiological characteristics ; growth was observed at pH 5 to 10 and in 0% to 6.0% NaCl. Two strains did not growth at a concentration above 7.0% NaCl and pH10. This bacterium was infected into health catfish hypodermically. Such injection was found to induce haemorrhagic ulcers very similar to those observed in naturally infected fish. At 24h post-infection, the red spot developed around the injection site and grew bigger to from a red sport area. At 120h post-infection, the muscle ncerosis was extended near the ventral fin. The seventy percent lethal dosage was appeared to water temperature at $25^{\circ}C$. Two strains were tested for drug senistiveity by plate method. KL-1 and KL-2 strains were sensitive to GM. K, N, S and SxT, but resistant to CF, L and VA.

• Membrane Journal
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• v.6 no.2
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• pp.86-95
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• 1996

Rotary disc ultrafiltration module(RDM) was developed for the separation of oil e$$\mu$sions. This module was devised to reduce the gel polarization phenomenon by decoupling the operation pressure and the surface velocity of solution in ultrafiltration(UF) processes. The rotary disc membrane consists of 3mm-thick ABS plate covered with UF membrane (UOP, U.S.A.). When the angular velocity($\omega$) was increased, the pure water flux was slightly decreased due to pressure drop caused by centrifugal force and slip flow at the surface of membrane. The pressure drop was proportional to the square of linear velocity(${\omega}r$). When the angular velocity was changed from 52.36rad/s to 2.62rad/s, the flux decline for 5% cutting oil in one-shaft RDM at $25^{\circ}C$ and 0.1MPa was 30.16%. In the lower concentrations, angular velocity tends to give less effect on the flux. Flux(J; $kg/m^{2} \cdot s$) in a rotating disc module is mainly a function of the bulk concentration($C_{B}$; %), the linear velocity(${\omega}r$; m/s) and the effective transmembrane pressure($\Delta P_{T}$ ; Pa). Using a modified resistance-in-series model, the flux data of cutting oil experiments were fitted to give the following equation.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.1
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• pp.77-83
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• 2011

In this thesis, 50W Doherty amplifier was designed and implemented for Beyond 3G's repeater and base-station. Auxiliary amplifier of doherty amplifier was implemented by Gate bias control circuit. Though gate bias control circuit solved auxiliary's bias problem, output characteristics of doherty amplifier was limited. To enhance the output characteristic relativize Drain control circuit And To improve power efficiency make 3-way Doherty power amplifier. therefore, 3-way GDCD (Gate and Drain bias Control Doherty) power amplifier is embodied to drain bias circuit for General Doherty power amplifier. The 3-way GDCD power amplifier composed of matching circuit with chip capacitor and micro strip line using FR4 dielectric substance of specific inductive capacity(${\varepsilon}r$) 4.6, dielectric substance height(H) 30 Mills, and 2.68 Mills(2 oz) of copper plate thickness(T). Experiment result satisfied specification of amplifier with gains are 57.03 dB in 2.11 ~ 2.17 GHz, 3GPP frequency band, PEP output is 50.30 dBm, W-CDMA average power is 47.01 dBm, and ACLR characteristics at 5MHz offset frequency band station is -40.45 dBc. Especially, 3-way DCHD power amplifier showed excellence efficiency performance improvement in same ACLR than general doherty power amplifier.

• Journal of Life Science
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• v.19 no.3
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• pp.349-355
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• 2009

Metabolic fingerprinting of microbial communities was investigated with Biolog GN2 plates using samples of biofilm and aeration tanks from an RABC (rotating activated Bacillus contactor) system - an advanced wastewater treatment system for the food wastewater of pig slaughterhouses. Aerobic and anaerobic results revealed the following four aspects. First, simple matching and pairs t-test of daily variation showed more defined qualitative and quantitative relatedness of active microbial communities than that of mere optical densities. Second, metabolic potentials were higher in biofilm than in aeration tanks (p<0.01), meaning higher activity of biofilm. Third, two aeration tanks showed the highest similarity (78%) and similar metabolic power (p=0.287). However, actively used carbon sources were different among samples, signifying change of active communities at each wastewater treatment step. Finally, aerobic and anaerobic metabolic fingerprinting patterns were different for the same samples representing activities of microaerophilic and/or anaerobic communities. These results suggest that daily variation and anaerobic incubation would help in the comparison of metabolic fingerprintings.