Sung K. Ahn

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Skin, as the outermost organ in the human body, continuously confronts the external environment and serves as a primary defense system. The protective functions of skin include UV-protection, anti-oxidant and antimicrobial functions. In addition to these protections, skin also acts as a sensory organ and the primary regulator of body temperature. Within(More)
PURPOSE Various therapeutic approaches have been suggested for preventing or reducing the adverse effects of topical glucocorticoids, including skin barrier impairment. Previously, we have shown that impairment of skin barrier function by the highest potency topical glucocorticoid, clobetasol 17-propinate (CP), can be partially prevented by co-application(More)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Dear Editor: Focal acantholytic dyskeratosis (FAD)(More)
Price dynamics in Indian cities were examined using cointegration analysis. We identified and calculated a common trend for prices in 25 major cities in India. Impulse response functions were obtained to calculate the rates of convergence to the prices and we found that the half-life of any shock is very small for Indian cities. Although a close to(More)
We develop a method for directly modeling cointegrated multivariate time series that are observed in mixed frequencies. We regard lower-frequency data as regularly (or irregularly) missing and treat them with higher-frequency data by adopting a state-space model. This utilizes the structure of multivariate data as well as the available sample information(More)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Fig. 1. The patient presented with depigmented(More)
Nevus sebaceous (NS) is a type of classical nevus or congenital malformation that is often present at birth and commonly involves the scalp or face. The lesion usually presents as a linear, yellow, hairless, and verrucous plaque. It has been well-established that several benign and malignant tumors can develop from the NS; however, there have been no(More)
Focal dermal hypoplasia, caused by mutations in PORCN, is an X-linked ectodermal dysplasia, also known as Goltz syndrome. Only seven cases of unilateral or almost unilateral focal dermal hypoplasia have been reported in the English literature and there have been no previously reported cases in the Republic of Korea. A 19-year-old female presented with scalp(More)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/ licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Fig. 1. Clinical features of the patient. (A, B)(More)