• The Journal of Advanced Prosthodontics
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• v.1 no.2
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• pp.107-112
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• 2009

STATEMENT OF PROBLEM. Macroscopic and especially microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Dental implants with modified surfaces have shown stronger osseointegration than implants which are only turned (machined). Advanced surface modification techniques such as anodic oxidation and Ca-P application have been developed to achieve faster and stronger bonding between the host bone and the implant. PURPOSE. The purpose of this study was to investigate the effect of surface treatment of titanium dental implant on implant stability after insertion using the rabbit tibia model. MATERIAL AND METHODS. Three test groups were prepared: sandblasted, large-grit and acid-etched (SLA) implants, anodic oxidized implants, and anodized implants with Ca-P immersion. The turned implants served as control. Twenty rabbits received 80 implants in the tibia. Resonance frequencies were measured at the time of implant insertion, 2 weeks and 4 weeks of healing. Removal torque values (RTV) were measured 2 and 4 weeks after insertion. RESULTS. The implant stability quotient (ISQ) values of implants for resonance frequency analysis (RFA) increased significantly (P <. 05) during 2 weeks of healing period although there were no significant differences among the test and control groups (P >. 05). The test and control implants also showed significantly higher ISQ values during 4 weeks of healing period (P < .05). No significant differences, however, were found among all the groups. All the groups showed no significant differences in ISQ values between 2 and 4 weeks after implant insertion (P >. 05). The SLA, anodized and Ca-P immersed implants showed higher RTVs at 2 and 4 weeks of healing than the machined one (P < .05). However, there was no significant difference among the experimental groups. CONCLUSION. The surface-modified implants appear to provide superior implant stability to the turned one. Under the limitation of this study, however, we suggest that neither anodic oxidation nor Ca-P immersion techniques have any advantage over the conventional SLA technique with respect to implant stability.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.141-145
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• 2008

Oxidative stabilities of sesame oil prepared from black sesame flour and white sesame flour, and commercial sesame oil prepared from whole white sesame were compared by measuring oxidation induction periods, peroxide values and electron donating abilities of each oil. Oxidation induction period (12.25 hr) of sesame oil prepared from black sesame flour was longer than those (4.37 and 9.1 hr, respectively) of sesame oil from white sesame flour and commercial sesame oil. Peroxide values of sesame oil prepared from black sesame flour, sesame oil prepared from white sesame flour and commercial sesame oil were 1.3, 18.2 and 1.7 meq/kg oil, respectively. We ascertained that the oxidative stability of sesame oil prepared from black sesame flour was superior than sesame oil from white sesame flour as well as ommercial sesame oil. This was based on the fact that electron donating ability of sesame oil prepared from black sesame flour was 9% higher than that of sesame oil prepared from white sesame flour at the same concentration. The superior oxidative stability of sesame oil prepared from black sesame flour was expected, not only because only it had lignans such as sesamol and sesamolin, but also because of its brownish coloring compounds such as tannin which were not contained in white sesame flour.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.421-427
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• 2009

A mixture of three dietary medicinal herb extracts (MHE, mulberry leaf:Japanese honeysuckle:goldthread = 48.5: 48.5:3.0) was prepared as an additive of hen's feed. One hundred-eight, 28-wk-old Lohmann Brown hens were assigned randomly with three levels of MHE in the diet (0, 0.3, and 1%). Hens were fed for 6 wks and eggs were collected in the 6th week, and stored at $4^{\circ}C$ for 14 days to investigate the effect of MHE on the quality and oxidative stability of eggs. Internal quality of the egg including weight, shell color, albumen height, yolk color, shell weight, shell thickness, and Haugh units was not different among the dietary treatments. The oxidation stability of raw and cooked egg was determined by 2-thiobarbituric acid reactive substances (TBARS) value, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2'-azinobis(3-ethylbenzonthianoline-6-sulfonic acid) ($ABTS^{+}$) radical reducing ability. Results indicated that TBARS value at day 0 and $ABTS^{+}$ radical reducing ability of eggs from hens fed MHE were higher than from the control group. However, DPPH radical scavenging activity showed no difference in both raw and cooked samples. Results of the present study indicate that dietary MHE may slightly enhance the oxidative stability of eggs.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.288-293
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• 1999

Postabsorptive serum iron level was determined after oral administration of the compounds to human. In serum and whole blood, $Fe^{3+}$ was measured by ion chromatography (IC) using a pyridine-2,6-dicarboxylic acid (PDCA) as an eluent. The serum sample solutions were pretreated with I N HCI and 50% TCA. The whole blood sample solutions were treated with 3 N HCI for 30 min at $125^{\circ}C$. The limit of detection (LOD) of the IC technique is $0.2 {\mu}M$ for$Fe^{2+}$and 0.1 $\mu$M for $Fe^{3+}$. The area under concentration (AUC) can be obtained by the above analytical condition. In addition, to compare the stability of $Fe^{2+}$ to that of $Fe^{3+}$ in pharamaceutical preparations, accelerated stability test was carried out. After storing the samples under $40^{\circ}C$, 75%RH in light-resistant container for various time intervals, the contents of iron of different valencies were determined separately by the IC technique and the change and/or the interchange of among those iron species in preparations was investigated. Iron raw materials are stable, but $Fe^{2+}$ in$Fe^{3+}$ source materials was slightly converted to $Fe^{3+}$ by oxidation. $Fe^{2+}$ in$Fe^{3+}$ source raw materials and $Fe^{3+}$ in $Fe^{2+}$ raw materials are determined as impurities. Therefore, IC technique is found to be an appropriate method for comparative evaluation of dissimilar bioavailability of $Fe^{2+}$ and $Fe^{3+}$, stability of $Fe^{2+}$ and $Fe^{3+}$ raw materials and preparations.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.601-612
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• 2020

The study assessed the stability for fresh beef patties with the inclusion of clove extract (CE) as a natural antioxidant in comparison to butylated hydroxytoluene (BHT) and ascorbic acid (AA) at frozen storage. Four different patties were made dependent on the added antioxidants: control (added no antioxidants), added with 0.02% BHT, 0.05% AA, and 0.1% CE. Inclusion of BHT, AA, and CE resulted in a significant reduction of thiobarbituric acid reactive substances (TBARS) and hue angle (h°) value and increase of redness (CIE a*) and chroma (C*) values (p<0.05). BHT, AA, and CE were observed effectively to retard lipid oxidation and increase color stability. BHT and AA revealed significantly (p<0.05) higher thiol content than the control and CE. However, the reduction percentage for thiol content in CE treated patties was lower than the control and AA-treated patties from first to last time of storage. Moreover, inclusion of AA and CE led to significantly (p<0.05) increased heme iron content when compared to BHT and the control. In conclusion, CE can replace the application of AA and BHT while improving lipid stability, heme iron content, and color stableness of fresh beef patties throughout frozen storage.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.376-376
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• 2012

Semiconductor nanowires (NWs) are future building block for nano-scale devices. Especially, Ge NWs are fascinated material due to the high electrical conductivity with high carrier mobility. It is strong candidate material for post-CMOS technology. However, thermal stability of Ge NWs are poor than conventional semiconductor material such as Si. Especially, when it reduced size as small as nano-scale it will be melted around CMOS process temperature due to the melting point depression. Recently, Graphene have been intensively interested since it has high carrier mobility with single atomic thickness. In addition, it is chemically very stable due to the $sp^2$ hybridization. Graphene films shows good protecting layer for oxidation resistance and corrosion resistance of metal surface using its chemical properties. Recently, we successfully demonstrated CVD growth of monolayer graphene using Ge catalyst. Using our growth method, we synthesized Ge/graphene core/shell (Ge@G) NW and conducted it for highly thermal stability required devices. We confirm the existence of graphene shell and morphology of NWs using SEM, TEM and Raman spectra. SEM and TEM images clearly show very thin graphene shell. We annealed NWs in vacuum at high temperature. Our results indicated that surface melting phenomena of Ge NWs due to the high surface energy from curvature of NWs start around $550^{\circ}C$ which is $270^{\circ}C$ lower than bulk melting point. When we increases annealing temperature, tip of Ge NWs start to make sphere shape in order to reduce its surface energy. On the contrary, Ge@G NWs prevent surface melting of Ge NWs and no Ge spheres generated. Furthermore, we fabricated filed emission devices using pure Ge NWs and Ge@G NWs. Compare with pure Ge NWs, graphene protected Ge NWs show enhancement of reliability. This growth approach serves a thermal stability enhancement of semiconductor NWs.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.711-716
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• 2010

New electroluminescent polymers with fluoro groups in vinylene units, poly(m-silylphenyl-p-phenylene-difluorovinylene) (m-SiP-PPDFV) have been synthesized by GILCH polymerization. These polymers have been used as the electroluminescent (EL) layers in single layer light-emitting diodes (LEDs) (ITO/PEDOT/polymer/Ca:Al). m-SiP-PPDFV shows PL around $\lambda_{max}$ = 452 nm and green EL around $\lambda_{max}$ = 497 nm. The current-voltage-luminance (I-V-L) characteristics of the polymers show turn-on voltages of 4.0 V approximately. Two fluoro groups were introduced on every vinylene units of m-SiP-PPV to give m-SiP-PPDFV in an attempt to increase the electron affinity of the parent polymer, and the devices show an increased color stability even with vinylene units. The color stability is attributed to the electron-withdrawing effect of the fluoro groups, which protect vinylene units from oxidation in PPV derivatives. We believe that fluoro groups can be introduced in vinylene units in order to attain excellent stability of PPV derivatives.

• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.597-606
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• 2019

Cellulose nanocrystals (CNCs) were successfully isolated from oil palm fronds (OPFs) using different concentrations of ammonium persulfate (APS), and their characteristics were analyzed by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, and thermogravimetric analysis (TGA). APS oxidation effectively isolated CNCs with rod-like morphology in nanometer scale. The dimensions of the CNCs decreased with increasing APS concentration. FTIR and XRD analyses revealed that all the CNCs showed crystals in the form of cellulose I without crystal transformation occurring during APS treatment. The relative crystallinity of the CNCs increased with increasing APS concentration, whereas their thermal stability decreased. An APS concentration of 2 M was found to be optimal for isolating the CNCs.

• Food Science of Animal Resources
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• v.39 no.5
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• pp.742-755
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• 2019

Cacao bean husk (Theobroma cacao L.) contains a high level of dietary fiber and therefore can be used as raw material in food processing. The objective of the present study was to measure the physicochemical properties and sensory traits of emulsion-type pork sausages with various levels of cacao bean husk powder (0.25%, 0.5%, 0.75%, 1%, and 2%). The moisture content in cooked sausages increased as the level of cacao bean husk power increased, whereas the protein content decreased (p<0.05). With respect to color, as the level of cacao bean husk power increased, there was a decrease in lightness and yellowness, but there was a considerable increase in redness (p<0.05). Cacao bean husk powder exhibited a positive effect on emulsion stability and apparent viscosity. In the sensory evaluation, increased level of cacao bean husk increased flavor acceptability; the 0.75% and 1% treatment groups showed significantly high overall acceptability (p<0.05). The thiobarbituric acid reactive species content of cooked sausages indicated that with the addition of cacao bean husk powder significantly inhibited lipid oxidation in the sausages during refrigerated storage (p<0.05). Overall, the findings of the present study suggest that adding 0.75% and 1% cacao bean husk powder as a natural ingredient in sausages can help develop meat products with excellent qualities.

• Journal of Animal Science and Technology
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• v.56 no.6
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• pp.21.1-21.7
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• 2014

This study was performed to investigate the physicochemical and microbiological properties of isoflavone-treated dry cured sausage from sulfur fed pork (0.3%) during storage at $15^{\circ}C$ for 45 days. Groups were divided into three treatments: dry-cured sausages produced with pork fed general diet as the control group (CON), sulfur-fed pork (SUL) and isoflavone-(0.25%) treated sulfur-fed pork (ISO). Moisture content in all groups decreased dramatically from 55-57% to 10-11% during storage, whereas crude protein, crude fat, and ash content increased (P < 0.05). The ISO group showed excellent antioxidant effect compared to CON during storage. Redness and lightness of ISO was higher than that of CON during storage. VBN in the ISO group was significantly lower than that in the CON and SUL treatments during 30 and 45 days of storage (P < 0.05). A total plate count of ISO was significantly lower than that of CON at 45 days (P < 0.05). In this study, adding isoflavone to meat products indicated prevention of lipid oxidation and improved color stability in meat products.