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Effects of Construction and Operation of Nuclear Power Plants on Benthic Marine Algae (원자력발전소의 건설과 가동이 저서 해조류에 미치는 영향)

  • 김영환
    • Korean Journal of Environmental Biology
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    • v.17 no.4
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    • pp.379-387
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    • 1999
  • During the past several decades, electricity generating plant increased with remarkable rapidity in Korea. Recently the increase has been much more rapid as the rate of industrialization has accelerated. Construction of nuclear power plants in coastal areas inevitably caused the perturbation of critical coastal habitats and thus influenced marine algal species composition. Particularly, an increase in the building of nuclear power plants led the amounts of heat discharged to increase exponentially. As far as the effects of cooling water and thermal discharges are concerned, benthic marine algae are likely to be vulnerable to a discharge. Heated effluents from nuclear power plants, with the temperature rises of 7~12$^{\circ}C$ under normal operating and design conditions, are discharged through the discharge canal and into natural water bodies. It is clear that the characteristic marine algal community is developed in the area affected by the thermal discharges; i.e. low species richness and low species diversity. Nevertheless, it is worthwhile to note that elevated temperatures exert differential effects depending on the algal populations. Benthic marine algae grown at the discharge canal can be regarded as warm tolerant species. 35 species (4 blue-green, 9 green, 8 brown and 14 red algae) of marine algae occurred more than 20eye frequency at discharge canal of three nuclear power plants in the east coast during 1992 ~ 1998 and thus can be categorized as warm tolerant species in Korea. To minimize the ecological impacts of waste heat on benthic marine algae, it is recommended that, in the future, nuclear power plants will have to employ some form of closed-cycle cooling for the condensers.

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Feasibility of Photodynamic Diagnosis for Challenging TUR-Bt Cases Including Muscle Invasive Bladder Cancer, BCG Failure or 2nd-TUR

  • Takai, Tomoaki;Inamoto, Teruo;Komura, Kazumasa;Yoshikawa, Yuki;Uchimoto, Taizo;Saito, Kenkichi;Tanda, Naoki;Kouno, Junko;Minami, Koichiro;Uehara, Hirofumi;Takahara, Kiyoshi;Hirano, Hajime;Nomi, Hayahito;Kiyama, Satoshi;Azuma, Haruhito
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.6
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    • pp.2297-2301
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    • 2015
  • Background: Despite widely adopted standard methods for follow-up including cystoscopy plus cytology, recurrence rates of non muscle-invasive bladder cancer (NMIBC) have not improved over the past decades, still ranging from 60% through 70%. Hence, widely acceptable surveillance strategies with excellent sensitivity are needed. Early recurrence has led to the development of a novel cystoscopy technique utilizing photodynamic diagnosis (PDD). Although, no studies have evaluated the efficacy of PDD for patients of MIBC, BCG failure or 2nd-transurethelial resection (TUR). Materials and Methods: The present study was performed from October 2012 through May 2013. IRB approved 25 patients initially underwent a cystoscopy examination of white light and blue light followed by the resection of tumors identified. Resections were performed from bladder mucosa areas considered suspicious at PDD, along with PDD negative normal bladder mucosa area resected by random biopsy. Specimens were divided into two groups, PDD positive and negative. Primary endpoints were sensitivity and specificity. Results: A total of 147 specimens extracted from 25 patients were included in the analysis. Some 45 out of 92 PDD-positive specimens were confirmed to have bladder cancer, and 51 out of PDD-negative 55 specimens were confirmed to be cancer negative. The sensitivity of PDD was 91.8% (45/49) and specificity was 52.0% (51/98). The sensitivity:specificity was 89.5% (17/19) : 47.6% (30/63) in 12 2nd-TUR patients, 90.5% (19/21) : 61.1% (11/18) in seven MIBC patients, and 95.0% (19/20) : 48.5% (16/33) in eight failed BCG cases. Conclusions: PDD-TURBT has high sensitivity to diagnose BC even for 2nd-TUR, MIBC or BCG failure cases.

Antioxidant and Tyrosinase Inhibition Activity Promoting Effects of Perilla by the Light Emitting Plasma (발광플라즈마 처리에 의한 들깨 부위별 항산화 및 Tyrosinase 저해 활성 효과)

  • Yoo, Ji Hye;Choi, Jae Hoo;Kang, Byeong Ju;Jeon, Mi Ran;Lee, Chan Ok;Kim, Chang Heum;Seong, Eun Soo;Heo, Kweon;Yu, Chang Yeon;Choi, Seon Kang
    • Korean Journal of Medicinal Crop Science
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    • v.25 no.1
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    • pp.37-44
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    • 2017
  • Background: The light emitting plasma (LEP) has recently attracted attention as a novel artificial light source for plant growth and functional component enhancement. We investigated the effects of LEP on whitening and antioxidant activities of the plant parts of perilla. Methods and Results: Previously germianted seeds of perilla were cultivated under different light conditions (fluoresce lamp, LED red, blue, white, green, and LEP) in a culture room for 2 months. Parts of perilla were harvested and extracted in 70% EtOH. The extracts were used to detect total phenolic contents, total flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), reducing power and tyrosinase inhibition activity as indicators of biological activity. Biological activity was highest in seedlings grown under LEP. The total phenolic content was highest in the stems and the total flavonoid content was highest in the roots of perilla exposed to LEP. The DPPH and ABTS radical activity in all the parts of perilla exposed to LEP were higher by approximately three-fold compared to that in the control (fluoresce lamp). The reducing power values of perilla significantly increased after treatment with LEP. In addition, all the extract of perilla plants exposed to LEP promoted the tyrosinase inhibitory activity. These results suggest that LEP can be an important artificial light source for enhancement of biological activity. Conclusions: LEP could promote whitening and antioxidant activity of perilla.

Synthesis of TiO2/active carbon composites via hydrothermal process and their photocatalytic performance (수열합성법에 의한 TiO2/active carbon 복합체의 제조 및 광촉매특성)

  • Kim, Dong Jin;Lee, Jin Hee;Lee, Byeong Woo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.5
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    • pp.241-245
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    • 2013
  • Granular bamboo-derived active carbons (AC) were impregnated (or coated) with $TiO_2$ nano crystalline powders. The photocatalytic activity of the $TiO_2$-impregnated active carbons ($TiO_2$/AC) were determined on the basis of the degradation rate of methylene-blue aqueous solution under UV irradiation. The active compounds of $TiO_2$ were impregnated onto the AC under moderate hydrothermal conditions (${\leq}200^{\circ}C$, pH 11). The mean size of $TiO_2$ particles calculated from BET surface area were found to be as 50 nm. The $TiO_2$ precipitates were coated on the cavities or pores on the surfaces of highly activated carbons. Since the hydrothermal process led to a lowering of the on-set temperature of the anatase-to-rutile transition of $TiO_2$ as low as $200^{\circ}C$, $TiO_2$ crystallites of a pure anatase or a mixed form with rutile were successfully coated on the AC depending on the synthesis temperatures.

A Study on the Costume of The Korean-Chinese Women in Yanbian, China - Focusing on 1990′s -

  • Zhang, Shun-Ai;Kim, Jin-Goo
    • The International Journal of Costume Culture
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    • v.4 no.1
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    • pp.25-33
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    • 2001
  • This study is to analyze Korean-Chinese women's Costume in Yabian with factors such as reform opening-up, economic growth, change of social values, development of technology, more education opportunities and influence of mass media. It divides the 1990's into two halves. Photos, interview, observation and relevant literature were used for this study. Even though economy grew rapidly, they needed to purchase daily goods other than clothes. In a way that they preferred practicality, it showed somewhat it was still developing. The trend in the first half of the 1990's was characterized : first, Synthetic or artificial fibers and ready-made suits were popular ; second, there still remained the men's style ; third, they wore Tanrikoo(彈力袴), Tisingkoo(體型袴), Jiaotakoo(脚袴) because of its properties of activeness and comfort ; fourth, shoulders looked ore prominent with pads as they were used in Chungsanfoo(中山服) ; fifth, clothes in grey and dark blue was in fashion ; sixth, they wore hand-made knit vests and sweaters and often mountain-climbing gears for its light and warm quality ; seventh, along with opening-up, various materials and colorful clothes were in style, which satisfied women's desire for beauty. They decorated Hanbok(韓服), using sleeves with colors, golden ornaments, flower patterns embroidery, materials of different color in collar and tie and dyes of sleeves and skirts. In the first half of the 1990's when the opening-up was beginning, there were diverse styles and colors in fashion, yet not close to good quality. As the economy grew, the second half of the 1990's was characterized by good palate, individuality, favouritism on foreign goods, rapid change of fashion. For instance, fur coat and woolen fabric were favored. Economic growth led to abundance of cloth, dyes and decorative materials. In addition, people possessed more clothing and it was possible for them to wear both Hanbok and wedding dress in wedding ceremony. People placed their standards on competency and financial ability rather than ideology. Worship disappeared and individuality arose. Therefore, apparel functioned not only as protection but as suits with aesthetic purpose. This resulted in introduction of bold style, imitation of western countries and extension of use of Hanbok. With the help of mass media, transportation, telecommunication, contact with Korean company and civilians, Korean and western cultures, through Korea, were accepted. Change in structure of economic status caused excessive spending and more educational opportunities that enabled people to accept foreign culture quickly. Values moved onto new, beautiful and better characteristics. it was possible to have suits ready-made due to improvement of mass production and cotten, wool, linen, silk became popular owing to technology. New technology, the bases of mass consumption, increased possession of clothing and accelerated change of fashion. In summary, women's Costume in Yanbian were affected by the factors in economy, politics, culture contact as well as change of society and technology.

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Effects of Thickness on Structural and Optical Properties of ZnO Thin Films Fabricated by Spin Coating Method (스핀코팅 방법으로 제작된 ZnO 박막의 두께에 따른 구조적 및 광학적 특성)

  • Yim, Kwang-Gug;Kim, Min-Su;Kim, Ghun-Sik;Choi, Hyun-Young;Jeon, Su-Min;Cho, Min-Young;Kim, Hyeoung-Geun;Lee, Dong-Yul;Kim, Jin-Soo;Kim, Jong-Su;Lee, Joo-In;Leem, Jae-Young
    • Journal of the Korean Vacuum Society
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    • v.19 no.4
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    • pp.281-286
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    • 2010
  • Thickness effects on the structural and optical properties of ZnO thin films fabricated by spin coating method have been carried out. With increase in the thickness of the ZnO thin films, the width and density of striation shape are increased. The ZnO thin film with thickness of 450 nm has a smooth surface morphology. For the ZnO thin film with a smooth surface, orientation factor ${\alpha}_{(002)}$ is sharply increased and FWHM of (002) diffraction peak is decreased compared to the ZnO thin films with a striation shape surface. Thickness and surface morphology of the ZnO thin films hardly affect the NBE peak position. However, the DLE peak position is blue-shifted as the surface morphology is changed from striation to smooth surface. The PL intensity ratio of the NBE to DLE is increased and the FWHM of NBE peak is decreased as the thickness of the ZnO thin films is increased.

Reflecting on the History and Future of Republic of Korea Navy (대한민국 해군창설 : 회고와 당부)

  • Hahm, Myung-Soo
    • Strategy21
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    • s.37
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    • pp.5-31
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    • 2015
  • The Republic of Korean Navy (ROKN) started from scratch. However, ROKN demonstrated its Blue Navy capabilities successfully to the entire world by conducting "Operation Early Dawn" at the Aden Bay, Yemen in Jan 2011. On the event of the 70th anniversary of the ROKN, I would like to retrospect past gleaning from voyages and challenges we had in the past. At the very inception of the ROKN, Korean government as well as senior military leaders recognized that it had no time to spare to clean up military those were insinuated deeply by communist agents. It was the top priority of the government. The Mongumpo Operation which was not well known, conducted by ROKN was one of the clean-up drive. The Korean War sometimes called as "a fire from land put-off at the sea". The world famous "Incheon Landing" which reversed war situation from the Nakdong Perimeter also done by Sea Power. ROKN conducted various maritime operations including not only Incheon Landing, but amphibious operation at Hungnam, mine sweeping, sea convoy, Wonsan Withdrawal. On the same day of the Korean War started, 25th June 1950, unless the victory of the ROKNS Baekdusan (PC 701) at the Korean Strait, the waning lamp light of Korea could not be rekindled by the participation of the U.N. The ROKN rescued the 17th regiment of Korean Army from the isolation at the Ongjin Peninsular and transported gold and silver bars stored at the Bank of Korea to the Navy supply deposit in Jinhae safely. ROKN special intelligence unit conducted critical HUMINT which led Incheon Landing success. One of important mission ROKN conducted successfully was not only transporting war fighting materials but also U.S. provided grains to starving Koreans. ROKN participated Vietnam campaign from 1960s and conducted numerous maritime transportation operations supplying materials to Vietnam military forces along the long coastal lines. Experienced Naval Officers and enlisted men who discharged and acquired as merchant marine certificate supported most of the U.S. sea lift operations throughout the Vietnam campaign. ROK-US Combined Forces which had been honed and improved its war fighting capabilities through the Korean War and out of Vietnam jungle playing key deterrent against threat from north Korea. However, those threat level will be completely different when north Korea finish its nuclear weapon ambition. In order to stand firm against north Korean nuclear threat, I would like to expect strong political leadership supporting nuclear submarine for ROKN.

Characteristics of Halophosphate Phosphor for Long-wavelength UV Prepared by Spray Pyrolysis (분무열분해법에 의해 합성된 장파장 자외선용 할로포스페이트계 형광체의 특성)

  • Sohn, Jong-Rak;Kang, Yun-Chan;Park, Hee-Dong;Yoon, Soon-Gil
    • Korean Journal of Materials Research
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    • v.12 no.7
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    • pp.555-559
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    • 2002
  • Blue-emitting $Sr_{10}$($PO$)$_{6}$ $Cl_2$:$Eu^{2+}$ and $_{(Sr,Mg) }$ 10/($PO_4$)$_{6}$ $Cl_2$:$Eu^{2+}$ phosphor particles for application of long-wavelength UV LED were prepared by ultrasonic spray pyrolysis. The luminescence characteristics under long- wave-length ultraviolet of the $Sr_{10}$ ($PO_4$)$_{6}$ $Cl_2$:$Eu^{2+}$ and (Sr,Mg)$_{10}$ ($PO_4$)$_{6}$ $Cl_2$:$^Eu{2+}$ phosphor particles prepared by the spray pyrolysis were compared with that of the commercial product. The PL intensity of the $Sr_{10}$ ($PO_4$)$_{6}$ $Cl_2$:$Eu^{2+}$ particles prepared by the spray pyrolysis was lower than that of the commercial $Sr_{10}$ ($PO_4$)$_{6}$ $Cl_2$:$Eu^{2+}$ particles because prepared $Sr_{10}$ ($PO_4$)$_{6}$ $Cl_2$:$Eu^{2+}$ phosphor particles had porous structure and hollow morphology. However, the PL intensity of the (Sr,Mg)$_{10}$($PO_4$)$_{6}$ $Cl_2$:$Eu^{2+}$ phosphor particles prepared by the spray pyrolysis was 8% higher than that of the commercial one. The high brightness of $(Sr,Mg)_{10}$ ($PO_4$)$_{6}$ $Cl_2$:Eu$^{2+}$ phosphor particles prepared by spray pyrolysis is due to the dense structure and high crystallinity of particles. The TEX>$(Sr,Mg)<_{10}$ ($PO_4$)$_{6}$ /$Cl_2$:$Eu^{ 2+}$ phosphor particles had main emission peak t 448 nm under long- wavelength ultraviolet.

An efficient protocol for the production of transgenic Alstroemeria plants via particle bombardment

  • Kim, Jong Bo
    • Journal of Plant Biotechnology
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    • v.47 no.1
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    • pp.66-72
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    • 2020
  • Alstroemeria plants were transformed by using an improved particle-gun-mediated transformation system. Friable embryogenic callus (FEC) induced from the leaves with axil tissues of Alstroemeria plant was used as the target tissue. Also, FEC was transformed with the bar gene was used as a selectable marker. In the case of plasmid pAHC25, 7.5% of the twice-bombarded FEC clumps showed blue foci, whereas the clumps with single bombardment showed only 2.3%. Additionally, a 90° rotation with double bombardment led to a higher frequency (6 times) of luciferase gene expression in PBL9780 than the control treatment. After 8 weeks of bombardment, more than 60 independent transgenic lines were obtained for pAHC25 and nearly 150 independent transgenic lines were obtained for PBL9780, all of which were resistant to PPT and demonstrated either GUS or luciferase activity. Regarding effect of osmotic treatment (0.2 M mannitol) with 7 different periods, the highest transient gene expression was obtained in 8 h before and 16 h after transformation in both pAHC25 and PBL9780. Compared with the control, at least three times more GUS foci and photons were observed in this treatment. With respect to different combinations of mannitol and sorbitol with 8 h before and 16 h after transformation, high numbers of transient and stable transgene expressions were observed in both 0.2 M mannitol and 0.2 M sorbitol used in the osmotic pre-culture. This combination showed the highest transformation efficiency in both pAHC25 (8.5%) and PBL9780 (14.5%). In the control treatment, only 10% of the FEC clumps produced somatic embryos. However, by using 0.2 M mannitol and 0.2 M sorbitol, the frequency of somatic embryos increased to 36.5% (pAHC25) and 22.9% (PBL9780). Of the somatic embryos produced, at least 60% germinated. Approximately 100 somatic embryos from these 210 independent transgenic lines from 2 plasmids developed into shoots, which were then transferred to the greenhouse. PCR analysis confirmed the presence of the bar gene. This is the report on the production of transgenic Alstroemeria plants by using particle bombardment with a high efficiency, thereby providing a new alternative for the transferring of gene of interests in Alstroemeria in the breeding program in the future.

Optical Simulation Study of the Improvement of Color-rendering Characteristics of White Light-emitting Diodes by Using Red Quantum-dot Films (적색 양자점 필름을 이용한 백색 발광 다이오드의 연색성 개선에 대한 광학 시뮬레이션 연구)

  • Lee, Gi Jung;Hong, Seung Chan;Lee, Jung-Gyun;Ko, Jae-Hyeon
    • Korean Journal of Optics and Photonics
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    • v.32 no.4
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    • pp.163-171
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    • 2021
  • Conventional white light-emitting diodes (LEDs) for lighting applications consist of blue LEDs and yellow phosphors, the spectrum of which lacks deep red. To improve the color-rendering characteristics of white LEDs, a red quantum-dot film was applied to the diffuser plate of LED lighting. The mean free paths of the quantum dots and the concentration of the TiO2 particles in the diffuser plate were adjusted to optimize the optical structure of the lighting. The color-rendering index (CRI) was greater than 90 for most conditions, which demonstrates that adoption of the red quantum-dot film is an effective way for improving the color-rendering properties of conventional white LEDs. The angular dispersion of color coordinates could be removed by utilizing the optical cavity formed between the diffuser plate and the reflector on the bottom of the lighting, where multiple passages of the light through the quantum-dot film reduced the differences in optical path length depending on the viewing angle.