Native and Non-native Reactions to ESL Compositions

This study investigated how English native speakers (ENSs) and Japanese native speakers (JNSs) of professorial, graduate, and undergraduate levels evaluate and edit ESL compositions written by Japanese college students. A total of 274 subjects first evaluated each of two compositions in terms of grammaticality, clarity of meaning, naturalness, and organization, using 10- point scales. ENSs were more strict about grammaticality and naturalness than were JNSs. Among the ENSs, the higher the academic status of the group, the more positive evaluation they made. The subjects then edited the composition, correcting everything that seemed ungrammatical, unacceptable or unnatural. ENSs provided far more corrections and corrected errors more accurately than did the JNSs. In both L1 groups, the higher the academic status, the more accurately the group corrected errors. JNSs left many errors uncorrected, especially errors involving articles, number, prepositions, and lexical items which occur in Japanese as loan words from English

Surface Roughness Control Based on Digital Copy Milling Concept to Achieve Autonomous Milling Operation

AbstractIn order to develop an autonomous and intelligent machine tool, a system named Digital Copy Milling (DCM) was developed in our previous studies. The DCM generates tool paths in real time based on the principle of copy milling. In the DCM, the cutting tool is controlled dynamically to follow the surface of CAD model corresponding to the machined shape without any NC program. In this study, surface roughness control of finished surface is performed as an enhanced function of DCM. From rough-cut to semi-finish-cut and finish-cut operations, the DCM selects cutting conditions and generates tool paths dynamically to satisfy instructed surface roughness Ra. The experimental verification was performed successfully

Melanin Reduces Ultraviolet-Induced DNA Damage Formation and Killing Rate in Cultured Human Melanoma Cells

Epidermal melanin pigment is believed to prevent development of ultraviolet (UV)–induced skin cancer by shielding cell nuclei and reducing DNA damage formation. It has not been experimentally proved, however, whether melanin reduces UV-induced DNA damage, because published experiments have been inconclusive. The present study was carried out to determine whether intracellular melanin protected cultured cells against UV-induced DNA damage and killing. Three human melanoma cell lines containing different amounts of melanin were used. Absorption spectrum, subcellular localization of melanin, and melanin concentration were examined in the three cell lines. Two types of DNA damages cyclobutane pyrimidine dimers and (6-4)photoproducts, were detected by an enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies specific for these photolesions. We found that melanin reduced the induction rates of both types of DNA damage in pigmented cells irradiated with low doses of UV in a melanin concentration-dependent manner. Almost no differences in repair capacity for the two types of photolesions were observed among the three melanoma cell lines. We also found that the more highly melanotic melanoma cell lines were more UV resistant than the less melanotic melanoma cell lines. These results suggest that intracellular melanin plays an important role in preventing UV-induced cell killing by reducing the formation of two types of DNA damage