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Notes: Photoluminescence (PL) and PL excitation (PLE) experiments on a GaAs/Al0.25Ga0.75As asymmetric coupled double quantum well are reported. In PLE, the seven peaks, four related to the heavy-hole coupled and the rest to the light-hole coupled excitonic states, are observed. The positions of seven peaks observed in PLE are in good agreement with the calculated results of multi-band envelope function approximation using the transfer matrix method. The result of the temperature-dependent PL above 100 K shows that, even though the wavefunctions are localized in different wells separated by 8 monolayer barrier, the heavy-hole coupled excitons in the two lowest levels are in thermal equilibrium. The observed activation energy is equal to the difference between the two levels.

Notes: CeO2 interlayers were used to control growth behavior of Bi4Ti3O12 thin films on MgO(001) substrates. The CeO2 layer grown at 740 °C had a preferential orientation with its c-axis normal to the film surface, so it could be used to grow an epitaxial Bi4Ti3O12(001)/CeO2(001)/MgO(001) heterostructure. On the other hand, the CeO2 layer grown at 650 °C showed a mixed texture of (001) and (111), and this interlayer enabled us to get a preferentially oriented Bi4Ti3O12(117)/CeO2(111)MgO(001) multilayer structure. © 1996 American Institute of Physics.

Notes: (Co1−xFex)Pt films were grown on a glass substrate by a rf sputtering and then annealed at 650–700 °C in a high vacuum. All the as-sputtered (Co1−xFex)Pt films deposited below 400 °C had a disordered structure and showed very low coercivities. With increasing the deposition temperature and Fe contents, the (111) texture was weakened in as-deposited (Co1−xFex)Pt ternary films. Vibrating sample magnetometer and x-ray diffraction data show that Co atoms in the L10 CoPt phase were substituted with Fe atoms. In-plane coercivities of these films decreased almost linearly with increasing Fe content which seemed to be due to the decrease of a crystalline anisotropy energy. © 1998 American Institute of Physics.

Notes: Photoluminescence excitation (PLE) studies were performed on GaAs-Al0.25Ga0.75As quantum wells (QWs) with fractional monolayer differences. The quantized PLE peaks and their submonolayer shifts clearly show that the heterointerface of thin QWs prepared by growth-interrupted molecular beam epitaxy has islands which extend out a lateral dimension larger than 100 A(ring), but they themselves have the microroughness smaller than 30 A(ring). The result of this work using exciton as the probe provides a clear evidence supporting the bimodal roughness model. © 1995 American Institute of Physics.

Notes: The purpose of this study is to know the prevalence of allergic patch test responses in patients with suspected fragrance allergy in Korea and to know the photoxic potentials of limited fragrance substances. Nine dermatology departments of university hospitals and one research institute of cosmetic company were participated in this study for the past 1 year. To inquire the specific fragrance allergens in Korea, eighteen fragrance ingredients were added to Korean standard series and fragrance series (Chemotechnique Diagnosis, Sweden). Among 422 patients, 83% were women and the most common topographic site was face. Except the fragrance mix and Balsam of Peru, Cinnamic alcohol and Sandalwood oil showed high frequency of positive responses. Among the added specific fragrance ingredients, 3-methyl-5-(2,2,3-trimethyl-3-cyclopenen-1-yl) pent-4-en-2-ol, alpha-isomethyl-ionone(methyl ionone gamma), Lyral showed high positive responses. With eighteen added specific fragrance substances, we have also performed two in vitro phototoxicity tests, 3T3 NRU phototoxicity test and photohemolysis test. 3T3 NRU phototoxicity test is a screening method for DNA or cellular damage and Photohemolysis test is a useful screening method for phototoxic chemicals that cause oxygen-dependent membrane damage. Only Lyral showed phototoxicity in photohemolysis test and no other fragrance ubstances showed phototoxicity in 3T3 NRU phtototoxicity test. We think our data are useful to know the current status of the frequent fragrance allergens in our society and the possible phototoxic potency of limited fragrance substances.

Notes: We compared the moisture sorption isotherms (MSI's) and their temperature dependence of composite foods with those of crust and filling. The MSI were determined on cracker, cookie, chocolate, and two types of composite foods such as CFI (cracker/chocolate/cracker) and CF2 (cookie/chocolate/cookie) at 20,30, and 40°C and 11–85% relative humidity, and fitted into the Guggenheim-Anderson-de Boer (GAB) equation. Chocolate had the lowest monolayer (mo) value, equilibrium moisture content (EMC), and sorption energy levels, followed by cookie and cracker. The CFI had higher EMC values and sorption energy than CF2. The GAB mo values and C1 values decreased with temperature, while C2 values increased with temperature.

Notes: Background   Perforating disorders are uncommon diseases characterized by transepidermal elimination histopathologically and include reactive perforating collagenosis, elastosis perforans serpiginosa, Kyrle's disease and perforating folliculitis. In addition, perforating disorders can develop in patients with diabetes mellitus, renal failure and even by accidental exposure of calcium salts.Methods   We report two cases of perforating disorder caused by chemical burn with commercially available salt-water* application for self-treatment of chronic dermatitis or pruritus.Results   The commercially used salt water for making bean curd was analyzed and it consisted of calcium and other salts without harmful heavy metals. We induced a similar phenomenon by experimental application of commercial salt water on guinea pigs.Conclusion   Bean curd is used as a food commonly in the Far-East, allowing a greater chance of exposure to salt water accidentally or occupationally. Bean curd is becoming more popular even in Western countries. To confirm causation, we induced a similar phenomenon in guinea pigs by experimental application of commercial salt water.*Salt water# (‘Kansoo’ in Korean) is used in the solidifying process of bean curd.

Notes: Background  A keloid results from excessive collagen deposition, the cause of which remains elusive. A thorough understanding of the pathophysiology of keloid tissue can help determine the most appropriate treatment strategy.Objectives  To assess the differences in gene expression between keloids and adjacent normal skin in order to define the genes involved in keloid formation.Methods  Three Korean patients with keloids underwent excision of the keloid and adjacent normal skin, which was used as the control. We investigated expression patterns of genes in the keloids and the normal skin using cDNA microarray and in situ hybridization techniques.Results  Nine genes in the keloid tissue were consistently upregulated over the 2·0 ratio compared with the normal control from the cDNA microarray composed of 3063 clones: collagen type I α1 (〈accessionId ref="info:ddbj-embl-genbank/NM_000088"〉NM_000088), DNA segment on chromosome 21 (unique) 2056 expressed sequence (D21S2056E, NNP-1, 〈accessionId ref="info:ddbj-embl-genbank/NM_003683"〉NM_003683), suppressor of Ty 5 homologue (〈accessionId ref="info:ddbj-embl-genbank/NM_003169"〉NM_003169), phosphoglycerate dehydrogenase (〈accessionId ref="info:ddbj-embl-genbank/NM_032692"〉NM_032692), adenosine triphosphate synthase β (〈accessionId ref="info:ddbj-embl-genbank/NM_001686"〉NM_001686), serine (or cysteine) proteinase inhibitor, clade H (heat shock protein 47, 〈accessionId ref="info:ddbj-embl-genbank/NM_001235"〉NM_001235), LIV-1 protein, oestrogen regulated (LIV-1, 〈accessionId ref="info:ddbj-embl-genbank/NM_012319"〉NM_012319), interleukin-11 receptor α (IL11RA, 〈accessionId ref="info:ddbj-embl-genbank/NM_004512"〉NM_004512) and carbonyl reductase 3 (CBR3, 〈accessionId ref="info:ddbj-embl-genbank/NM_001236"〉NM_001236). From the in situ hybridization study, the staining signals in the keloid tissue hybridized with anti sense probes of NNP-1 mRNA were stronger than signals in normal controls. Further, endothelial epithelium, but not the epidermis, expressed the signal equally in both keloid and normal control tissue.Conclusions  We identified nine upregulated genes in keloid tissue using cDNA microarray. Of the nine, the NNP-1 gene was confirmed by topological information using the in situ hybridization technique. We conclude that these nine genes, especially NNP-1, probably contribute either directly or indirectly to keloid formation.