• Journal of Radiation Industry
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• v.10 no.4
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• pp.189-192
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• 2016

$^{68}Ga$ has emerged as a promising candidate for non-invasive diagnostic imaging within Positron Emission Tomography (PET) because of its advantageous radiochemical characteristics ($t_{1/2}=68min$, ${\beta}^+$ yield ~89%). $^{68}Ga$ forms a stable chelation with various ligands and it is possible to be quickly and easily study using a $^{68}Ge/^{68}Ga$ generator. Commercial $^{68}Ge/^{68}Ga$ generators are chromatographic system using the inorganic materials such as alumina and tin dioxide which are employed as column matrixes for $^{68}Ge$. In this study, we tried out to make $^{68}Ge/^{68}Ga$ generator system with the $^{68}GeO_2$ microstructures for column matrix. $^{68}Ge$ tends to have stable bond with oxide as $^{68}GeO_2$ microstructures. The $^{68}GeO_2$ has been synthesized by hydrolysis of $GeCl_4$ (sol-gel method) and characterized by X-ray diffraction and scanning electron microscope for geometrical analysis. The stability of $GeO_2$ was tested using eluents with diverse solvents(water, ethanol and 0.1 N HCl). The radioactivity of $^{68}Ga^{3+}$ in eluate through $GeO_2$ was measured to prove a function as column material for a generator.

• Journal of dental hygiene science
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• v.13 no.2
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• pp.135-141
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• 2013

One factor for successful prognosis of finished dental prosthesis is good marginal fit. The purpose of this study in vitro investigation was to compare the marginal fit of all-ceramic crown before and after porcelain veneering, to evaluate the influence of high temperature of the porcelain firing on the fit. For this experiment, model of abutment tooth of maxillary right central incisor was prepared. Ten working models were produced. Ten zirconia cores were made by dental computer aided design/computer aided manufacturing system. The marginal fit of specimens were examined using silicone replica technique. Silicone replicas were sectioned four times and were measured through a digital microscope (${\times}160$). Marginal fit is a distance connected between edge end part of specimen and abutment margin. Each specimens was measured twice, the first measurement was done prior to veneering porcelain firing, while the second measurement was done after the porcelain firing to evaluate this process. Statistical analyses were performed with paired t-test. $Mean{\pm}SD$ marginal fit was $60.8{\pm}14.2{\mu}m$ for zirconia core and $86.1{\pm}13.3{\mu}m$ for all-ceramic crown. They were statistically significant differences (p<0.001). But all specimens showed a marginal fit where the gap widths ranged within the clinical recommendation ($120{\mu}m$), all-ceramic crown production using the zirconia core was adequate.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.928-935
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• 2008

The myostatin gene of seven important meat (Beltex (Australia), Beltex$\times$Huyang (F1), Meat and Multi-Prolific Chinese Merino Fine Wool, Meat Chinese Merino Fine Wool and Dorper (South Africa)) and non-meat (Huyang and Kazak) sheep breeds was analyzed to study the genetic basis of muscular hypertrophy (double muscling) phenotype in sheep. SNPs, four in regulatory regions and several in the introns in the myostatin gene, were identified, and the former four SNPs were used for further studies. Twelve haplotypes were predicted by PHASE program, of which four main haplotypes (1, 3, 7, 9) were present in 90% of the 364 sheep in the study. Haplotypes 1-4 were mainly present in meat breeds while haplotypes 7 and 9 dominated the non-meat breeds. The association between haplotypes and average daily gain (ADG) was analyzed among 116 sheep with production data, Haplo2 (CGAA) and Haplo8 (TGAA) were identified to have significant (p<0.05) effect on ADG by the model (JMP5.1 software) taking into account the effects of breed, family background, haplotype, birth weight and sex. ADG of these haplotype groups also correlated well (r = 0.82) with hypertrophic phenotype scores. In conclusion, the mutations -956 (T$\rightarrow$C), -41 (C$\rightarrow$A) and 6223 (G$\rightarrow$A) involved in Haplo2 and 8 may be associated with the double-muscling trait by influencing myostatin function and be suitable markers in selecting meat sheep.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.5
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• pp.602-610
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• 2013

This study was aimed to evaluate the cavernosal relaxation effect of Crataegii fructus(CF) in the contracted rabbit penile corpus cavernosum by agonists.In order to study the effect of CF on the vasoconstriction of rabbit penile corpus cavernosum, isolated rabbit penile corpus cavernosum tissues were used for the experiment using organ baths containing Krebs solution.To investigate the cavernosal relaxation of CF, CF extract at $0.01{\sim}3.0mg/m{\ell}$ was added after penile corpus cavernosum were contracted by norepinephrine(NE) $1{\mu}M$. To analyze the mechanism of CF's vasorelaxation, CF extract infused into contracted penile tissues by NE after each treatment of indomethacin(IM), $N{\omega}$-nitro-L-arginine(L-NNA), methylene blue(MB), tetraethylammonium chloride(TEA).To study the effect of CF on influx of extracellular calcium chloride($Ca^{2+}$) in penile tissues, in $Ca^{2+}$-free krebs solution, $Ca^{2+}$ 1 mM infused into contracted penile tissues by NE after pretreatment of CF. Cytotoxic activity of CF on human umbilical vein endothelial cell(HUVEC) was measured by MTT assay, and nitric oxide(NO) prodution was measured by Griess reagent. CF relaxed cavernosal strip with endothelium contracted by NE, but in the strips without endothelium, CF-induced relaxation was significantly inhibited. The pretreatment of L-NNA, MB, TEA decreased significantly on the cavernosal relaxation than not-treatment of them. But the pretreatment of IM had no significant effect on the cavernosal relaxation. In $Ca^{2+}$-free krebs solution, when $Ca^{2+}$ infused into contracted penile tissues by NE, pretreatment of CF inhibit contraction induced by adding $Ca^{2+}$.NO production wasn't increased by treatment of CF on HUVEC. This findings showed that CF is effective for the relaxation of rabbit penile corpus cavernosum, and we suggest that CF relax rabbit corpus cavernosal smooth muscle through multiple action mechanisms that include increasing the release of nitric oxide from corporal sinusoidal endothelium, inhibition of $Ca^{2+}$ mobilization into cytosol from the extracellular fluid, and maybe a hyperpolarizing action.

• Journal of Microbiology and Biotechnology
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• v.30 no.6
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• pp.937-945
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• 2020

N-acyl-homoserine lactone (AHL)-mediated quorum sensing (QS) plays a major role in development of biofilms, which contribute to rise in infections and biofouling in water-related industries. Interference in QS, called quorum quenching (QQ), has recieved a lot of attention in recent years. Rhodococcus spp. are known to have prominent quorum quenching activity and in previous reports it was suggested that this genus possesses multiple QQ enzymes, but only one gene, qsdA, which encodes an AHL-lactonase belonging to phosphotriesterase family, has been identified. Therefore, we conducted a whole genome sequencing and analysis of Rhodococcus sp. BH4 isolated from a wastewater treatment plant. The sequencing revealed another gene encoding a QQ enzyme (named jydB) that exhibited a high AHL degrading activity. This QQ enzyme had a 46% amino acid sequence similarity with the AHL-lactonase (AidH) of Ochrobactrum sp. T63. HPLC analysis and AHL restoration experiments by acidification revealed that the jydB gene encodes an AHL-lactonase which shares the known characteristics of the α/β hydrolase family. Purified recombinant JydB demonstrated a high hydrolytic activity against various AHLs. Kinetic analysis of JydB revealed a high catalytic efficiency (k_cat/K_M) against C4-HSL and 3-oxo-C6 HSL, ranging from 1.88 x 10⁶ to 1.45 x 10⁶ M^-1 s^-1, with distinctly low K_M values (0.16-0.24 mM). This study affirms that the AHL degrading activity and biofilm inhibition ability of Rhodococcus sp. BH4 may be due to the presence of multiple quorum quenching enzymes, including two types of AHL-lactonases, in addition to AHL-acylase and oxidoreductase, for which the genes have yet to be described.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1425-1429
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• 2005

Megaspahera elsdenii YJ-4, which was previously isolated as a producer of trans-10, cis-12 CLA, was studied for its carbon source on the CLA production. M. elsdenii YJ-4, was incubated with glucose and lactose, and cultured in batch and continuous culture systems with linoleic acid at various pHs to investigate CLA production. Batch cultures of the ruminal bacterium, M. elsdenii YJ-4, were resistant to stearic acid and linoleic acid, and little growth inhibition was observed even when the fatty acid concentration in the culture was as much as 4 mg $ml^{-1}$. Stationary phase batch cultures (0.25 mg bacterial protein $ml^{-1}$) that had been grown on lactate and incubated with linoleic acid (0.20 mg $ml^{-1}$) produced approximately 12 ${\mu}g$ trans-10, cis-12 CLA mg $protein^{-1}$ and little cis-9, trans-11 CLA was detected. Some linoleic acid was converted to hydrogenated products (chiefly stearic acid), but these fatty acids were less than 5 ${\mu}g$ mg bacterial $protein^{-1}$. Stationary phase batch cultures that had been grown on glucose produced at least 3-fold less trans-10, cis-12 CLA than ones grown on lactate. Cells from lactate-limited continuous cultures produced less trans-10, cis-12 CLA than those from batch culture, but only if the pH was greater than 6.4. When the pH of the lactate-limited continuous cultures was lower than 6.4, trans-10, cis-12 CLA and hydrogenated products declined. Cells from glucose-limited continuous cultures produced less trans-10, cis-12 CLA and hydrogenated products than the cells that had been limited by lactate, but pH had little impact on this production. These results support the idea that M. elsdenii YJ-4 could be one of the major producers of trans-10, cis-12 CLA which causes cows to produce milk with a low fat content.

• Korean Journal of Optics and Photonics
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• v.10 no.6
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• pp.500-506
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• 1999

We designed and fabricated a bidirectional optical transceiver module for low cost access network. An integrated chip forming a pin-PD on an 1.3 urn FP-LD was assembled by flip-chip bonding on a Si optical bench, a single mode fiber with an angled end facet was aligned passively with the integrated chip on V-groove of Si-optical bench. Gaussian beam theory was applied to evaluate the coupling coefficients as a function of some parameters such as alignment distance, angle of fiber end facet, vertical alignment error. The theory is also used to search the bottle-neck between transmittance and receiving coupling efficiency in the bi-directional optical system. Tn this paper, we confirmed that reduction of coupling efficiency by the vertical alignment error between laser beam and fiber core axis can be compensated by controlling the fiber facet angle. In the fabrication of sub-module, a'||'&'||' we made such that the fiber facet have a corn shape with an angled facet only core part, the reflection of transmitted laser beam from the fiber facet could be minimized below -35 dE in alignment distance of 2: 30 /J.m. In the same condition, transmitted output power of -12.1 dEm and responsivity of 0.2. AIW were obtained.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.362-362
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• 2014

Atomic layer deposition (ALD) can be regarded as a special variation of the chemical vapor deposition method for reducing film thickness. ALD is based on sequential self-limiting reactions from the gas phase to produce thin films and over-layers in the nanometer scale with perfect conformality and process controllability. These characteristics make ALD an important film deposition technique for nanoelectronics. Tantalum pentoxide ($Ta_2O_5$) has a number of applications in optics and electronics due to its superior properties, such as thermal and chemical stability, high refractive index (>2.0), low absorption in near-UV to IR regions, and high-k. In particular, the dielectric constant of amorphous $Ta_2O_5$ is typically close to 25. Accordingly, $Ta_2O_5$ has been extensively studied in various electronics such as metal oxide semiconductor field-effect transistors (FET), organic FET, dynamic random access memories (RAM), resistance RAM, etc. In this experiment, the variations of chemical and interfacial state during the growth of $Ta_2O_5$ films on the Si substrate by ALD was investigated using in-situ synchrotron radiation photoemission spectroscopy. A newly synthesized liquid precursor $Ta(N^tBu)(dmamp)_2$ Me was used as the metal precursor, with Ar as a purging gas and $H_2O$ as the oxidant source. The core-level spectra of Si 2p, Ta 4f, and O 1s revealed that Ta suboxide and Si dioxide were formed at the initial stages of $Ta_2O_5$ growth. However, the Ta suboxide states almost disappeared as the ALD cycles progressed. Consequently, the $Ta^{5+}$ state, which corresponds with the stoichiometric $Ta_2O_5$, only appeared after 4.0 cycles. Additionally, tantalum silicide was not detected at the interfacial states between $Ta_2O_5$ and Si. The measured valence band offset value between $Ta_2O_5$ and the Si substrate was 3.08 eV after 2.5 cycles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.392-402
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• 1987

To know the effect of presowing seed soaking with some growth substances (kinetin, IAA, ethrel and salicylic acid) on vegetative growth and yield contributing parameters in soybean [Glycine max (L.) Merrill] the investigation was undertaken. The salient features from the study are;-All the treatments showed the enhancement effect on vegetative growth, viz. seediling emergence, germination percentage, plant height, number of leaves and branches per plant as compared with control, whereas salicylic acid delayed the seedling emergence process and lowered the germination percentage.-Nodule initiation, number of nodules and nodule weight were hastened and increased respectively under all the treatments whereas IAA showed an opposite effect on all the parameters at the early stages of nodule development.-Kinetin, IAA and ethrel showed the significant enhancement effect on the levels of biochemical parameters throughout the time of seed development whereas salicylic acid and water showed the tendency similar to that of control.-Yield and its components, viz. number of flowers, pods and seeds per plant were significant increased under all the treatments but they didn't show any significant enhancement effect on number of seeds per pod and pod setting rate. One hundred seed weight was lower under all the treatments, indicating the dilution effect resulting from incapability of increased number and size of source to provide the increased size of sink with assimilates.

• 한국노년학
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• v.31 no.3
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• pp.607-621
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• 2011

Purpose The purpose of this study was to examine the relationship between physical activities, sleep disturbance, and health related quality of life (HRQOL) in patients with chronic obstructive pulmonary disease (COPD). Methods A descriptive survey design used pretest dataset of COPD symptom management intervention study (N=245). Measures included the international physical activity questionnaire, the COPD and asthma sleep impact scale, and the St. George's respiratory questionnaire of HRQOL. The data were analyzed using descriptive analysis, t-test, ANOVA, Pearson correlation coefficients, and simultaneous multiple regression by the SPSS WIN 18.0 program. Results The mean scores (SD) of HRQOL and sleep disturbance were 36.04 (19.43) and 14.33 (6.20), respectively. About 32% of participants were physically inactive. The multivariate approach showed the patients who have more sleep disturbance (β=.27), lower levels of FEV1 % predicted (β=-.23), lower physical activities (β=-.19), lower household income (β=-.16), and diagnosed longer than 5 years (β=.14) reported lower HRQOL (R²=.34). Conclusion The findings of this study suggest that improving the quality of sleep and physical activities can be efficient strategies for HRQOL in patients with COPD. Future research in enhancing HRQOL through improving sleep quality and physical activities is needed.