• Journal of Photoscience
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• v.9 no.2
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• pp.373-375
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• 2002

Lhcb genes encoding light-harvesting chlorophyll-a/b binding (LHC) proteins of photosystem (PS) II were comprehensively characterized using the expressed sequence tag (EST) databases in the green alga, Chlamydomonas reinhardtii. The gene family was composed of eight Lhcb genes including four new genes, which were isolated and sequenced. The effects of light intensity on the levels of mRNAs accumulation of multiple Lhcb genes were studied under various conditions. The results indicate that Lhcb genes are coordinately regulated in response to light conditions, and repressed when the input light energy exceeded the requirement for $CO_2$ assimilation. The effects of high light on the expression of the Lhcb genes observed in the presence of an electron transport inhibitor, DCMU, and in mutants deficient in photosynthetic reaction centers suggest the presence of two alternative mechanisms for regulating the genes expression under high-light conditions.

• Proceedings of the Korean Society of Potoscience Conference
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• 2005.06a
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• pp.74-75
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• 2005

• Journal of Photoscience
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• v.9 no.2
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• pp.379-381
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• 2002

The major electron transfer cofactors in photosystem II have been studied by pulsed EPR, pulsed electron electron double resonance (PELDOR) and laser excited spin polarized electron spin echo envelope modulation (ESEEM) methods, in non-oriented and oriented photosystem II membranes. Distances between radical pairs were determined trom the observed dipole interaction constants to be 27.3 A for P680-QA, 30 A, etc. with the error within 1 A. Angles between the distance vector and membrane normal was determined by orientation dependence of oriented membranes with the accuracy of 5˚ The results were compared with the recent structural data by X-ray analysis.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.10-10
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• 1999

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1547-1550
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• 2013

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1675-1679
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• 2003

The photodynamics of excited-state intramolecular proton transfer reaction of 1-hydroxyanthraquinone (1-HAQ) and 1-deuterioanthraquinone was investigated in toluene with time-resolved emission and femtosecond transient transmittance techniques at room temperature. The temporal profiles of transient transmittance of 1-HAQ could be well described with multi-decaying time constants. The ultrafast time constant within ca. 260 fs reflects the dynamics of proton transfer. The decay component of 2 ps is assigned to an additional proton translocation process induced by the intramolecular vibrational relaxation, whereas the decay component of 18 ps is assigned to the vibrational cooling process, while the long component (200 ps) can be explained in terms of the relaxation from excited-state keto-tautomer to its ground state. Time-resolved anisotropy decay dynamics and isotope effects on the photodynamics reveals that the ESIPT from enol-tautomer to keto-one of 1-HAQ is barrierless reaction and coupled to a vibrational relaxation process.

• Journal of Photoscience
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• v.8 no.2
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• pp.75-77
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• 2001

The Grignard reaction of methyl pyropheophorbide-a (MPP-a) was performed to introduce lengthy alkyl chain for improving lipophilicity. After the introduction of alkyl chain to the both of carbonyls, peripheral aldehyde and cyclopentanone, the obtained diol 3 was subjected to dehydration to give monodehydrate product 4 selectively. The Qy band of prepared compounds were affected by the substituents on the Qy axis (N$\sub$21/-N$\sub$23/).

• Rapid Communication in Photoscience
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• v.2 no.3
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• pp.72-75
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• 2013

Bulk nanobubble is one of the nanoscopic gaseous state found in the solution. We measured transient absorption spectra of eosin Y in the excited triplet state ($^3EY^{2-*}$) to elucidate differences in the dissipation process of the bulk nanobubble of oxygen molecule at air pressure. The time dependence of the oxygen dissipation process was classified three time domains (P1, P2 and P3). The comparison of ordinary bubbling method gave different results at P3 in contrast to similar results at P1 and P2, indicating the existence of characteristic dissolving state in the case of nanobubble.

• Progress in Medical Physics
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• v.16 no.2
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• pp.104-109
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• 2005

Photodynamic therapy (PDT) is one of the expectable current cure operation methods. Tumor tissue is treated by abundant oxygen in a body and generated singlet or free radical from exterior laser diode and photosensitizer. Current problem of PDT is the low penetration power of the light beam in a deep seated large tumor and solid tumor thus results in low treatment outcome. In the study, we tried to develop interstitial photodynamics therapy treatment to solve this problem. As the accurate determination of light dosimetry in biological tissue is one of the most important factors affecting the effectiveness of PDT, parameters used in this study are the optical property of biological tissue. Since biological tissues have large scattering coefficient to visible light the penetration depth of a biological tissue in visible light region is only $15\~20$ mm. We showed that it is possible to measure fluence rate and penetration depth within the biological tissues by Monte Carlo simulation very well. Based on the MC simulation study, the effectiveness of interstitial photodynamic therapy on tumor control in solid tumor was proved through in vivo animal experiment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3131-3138
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• 2015

At a dermatology during the skin care, photodynamic therapy(PDT) is carried after 5-aminolevulinic acid(ALA), light sensitive material, is applied. At a skin care shop, using drug is prohibited. Thus, the aim of this research was to see the effect of the acne skin by irradiating PDT to the skin without applying ALA. The research method was that 24 female undergraduates who had acne on their face at the level of mild or comedonal, and the participants were divided into four groups(group1: no treatment, group 2: 420 nm of blue visible light, group 3: 660 nm of red visible light and group 4: blue and red visible light). The participants of group 2, 3 and 4 were irradiated with visible light for 20 minutes per week for 6 weeks, and they were compared to group 1. As a result of the research, the number of erythema, sebum, papules and pustules of those who were irradiated with visible light decreased, and the pore size of those also decreased while the amount of moisture increased. If an skin care shop applies PDT to the existing acne skin care, that PDT will influence on the program of a skin care shop is expected.