The flowers of Coreopsis lanceolata were extracted with 80% aqueous MeOH and the concentrates were partitioned into EtOAc, n-BuOH, and H 2 O fractions. The repeated silica gel (SiO 2) and octadecyl silica gel column chromatographies for the EtOAc fraction led to isolation of one flavonol and one benzoyl compounds. The chemical structures of the compounds were respectively determined as melanoxetin (1) and protocatechuic acid methyl ester (2) based on spectroscopic analyses including NMR, IR, and MS. These two compounds were isolated for the first time from C. lanceolata flowers in this study. All fractions and the isolated compounds were evaluated for 2,2-diphenyl-1picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activities.

Scaffolds of tissue engineering should be biocompatible and biodegradable for cell attachment, proliferation and differentiation. In the various scaffold fabrication, 3D printing technique can make the three dimensional scaffold with interconnected pores for cell ingrowth. Polycaprolactone (PCL) is biodegradable polyester with a low melting temperature and has been approved by the Food and Drug Administration (FDA). In this study, PCL scaffold was fabricated by 3D bioprinting system and surface modification of PCL scaffold was controlled by NaOH treatment. Morphological change and wetability of NaOH-treated scaffold were observed by SEM and contact angle measurement system. The remnant of PCL treated with NaOH was measured by ATR-FTIR. In vitro study of scaffolds was evaluated with WST-1 and ALP activity assay. NaOH treatment of PCL scaffolds increased surface roughness, hydrophilicity, cell proliferation and osteogenic differentiation. These results indicate that NaOH-treated PCL scaffold made by 3D bioprinting has tissue engineered potential for the development of biocompatible material.

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The whole plants of Loranthus tanakae were repeatedly extracted with 80% aqueous MeOH and the concentrate was partitioned into ethyl acetate (EtOAc), n-butyl alcohol (n-BuOH) and H 2 O fractions. The repeated silica gel (SiO 2 ), octadecyl SiO 2

Although a use of hearing aids improves speech audibility, it is known that elderly hearing-impaired listeners often exhibit difficulty understanding speech in background noise. The purpose of this study was to examine a short-term (8-week) auditory training in word-recognition performance of 24 old hearing aid users. Twelve aged listeners (M=76.2 yrs) participated as auditory training group (ATG), and other twelve old listeners (M=74.0 yrs) served as non-training group (NTG). The ATG received forty-minute auditory training twice a week across the entire 8 weeks of training. During the training, the target monosyllabic words (Korean monosyllabic words) were presented in both open-set and closed-set aided conditions. All the words were presented at the most comfortable level of each participant with four different signal-to-noise ratios (SNRs of-5, 0, +5, +10 dB). To check the training benefit, word-recognition performance of ATG was tested after 1-, 4-, 8-week trainings. Results showed that word recognition performance of NTG did not improve as expected. Word recognition score of ATG was, however, significantly increased after 8-week training. Even though 4-week training results revealed a tendency of increment in word-recognition performance, a positive change after 4-week training was not significant. The amount of improvement after 8-week auditory training was the greatest at +10 dB SNR and the least at-5 dB SNR. The results indicate that the short-term (8-week) auditory training would be beneficial for old listeners to recognize speech in the background noise yet the training effect would depend on the SNRs. Therefore, at least 8 weeks of training in various listening conditions should be considered for elderly hearing aid users who want training benefit in daily listening and communication. KEY WORDS：Auditory training•Elderly hearing impaired•Hearing aid•Signal-to-noise (SNR)•Word recognition score.