Physicochemical characteristics and antioxidant activity of cold brew teas depending on different sterilization temperature

Yuri Kang,Daedong Kim,Jaehong Shin,Hyun Jung Kim 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

Sterilization is a crucial process for the safety of food products to keep their quality properties. This study investigated the effect of sterilization temperature (60, 65, 70, and 75℃ for 30 minutes) on the microbiological analysis, physicochemical characteristics, and in vitro antioxidant activities of four different cold brew teas (green tea, rooibos tea, rosemary tea, and hibiscus tea). In the microbiological assay, the count values of aerobic bacteria decreased in all sterilized cold brew teas (0-32 cfu/mL) compared with unsterilized teas (>1,700 cfu/mL). E. coli were not counted in all teas. After sterilization at 75℃, the soluble solid content of green tea was decreased and the color value increased. The total polyphenol contents of all cold brew teas were significantly reduced by sterilization at 75℃ (p<0.05). In addition, DPPH and ABTS<SUP>+</SUP> radical scavenging activity were changed after sterilization at 75℃. However, the physicochemical properties and antioxidant activities were not changed in other sterilization temperatures. This study showed that the sterilized cold brew teas were safe and their quality characteristics were not changed under 75℃.

Three-dimensional dose reconstruction-based pretreatment dosimetric verification in volumetric modulated arc therapy for prostate cancer

Yuri Jeong,Jeong Geun Oh,Jeong Ku Kang,Sun Rock Moon,Kang Kyoo Lee 대한방사선종양학회 2020 Radiation Oncology Journal Vol.38 No.1

Purpose: We performed three-dimensional (3D) dose reconstruction-based pretreatment verification to evaluate gamma analysis acceptance criteria in volumetric modulated arc therapy (VMAT) for prostate cancer. Materials and Methods: Pretreatment verification for 28 VMAT plans for prostate cancer was performed using the COMPASS system with a dolphin detector. The 3D reconstructed dose distribution of the treatment planning system calculation (TC) was compared with that of COMPASS independent calculation (CC) and COMPASS reconstruction from the dolphin detector measurement (CR). Gamma results (gamma failure rate and average gamma value [GFR and γAvg]) and dose-volume histogram (DVH) deviations, 98%, 2% and mean dose-volume difference (DD98%, DD2% and DDmean), were evaluated. Gamma analyses were performed with two acceptance criteria, 2%/2 mm and 3%/3 mm. Results: The GFR in 2%/2 mm criteria were less than 8%, and those in 3%/3 mm criteria were less than 1% for all structures in comparisons between TC, CC, and CR. In the comparison between TC and CR, GFR and γAvg in 2%/2 mm criteria were significantly higher than those in 3%/3 mm criteria. The DVH deviations were within 2%, except for DDmean (%) for rectum and bladder. Conclusions: The 3%/3 mm criteria were not strict enough to identify any discrepancies between planned and measured doses, and DVH deviations were less than 2% in most parameters. Therefore, gamma criteria of 2%/2 mm and DVH related parameters could be a useful tool for pretreatment verification for VMAT in prostate cancer.

Busbar differential protection in conjunction with a current transformer compensating algorithm

Kang, Y.C.,Yuri, J.S.,Lee, B.E.,Kang, S.H.,Jang, S.I.,Kim, Y.G. IET 2008 IET GENERATION TRANSMISSION AND DISTRIBUTION Vol.2 No.1

<P>The design, evaluation and implementation of a busbar differential protection relay that operates in conjunction with a current transformer (CT) compensating algorithm are described. Prior to saturation, the secondary current of a CT is not compensated. The compensating algorithm detects the start of first saturation on the basis of the third-difference function of the current and estimates the core flux at the first saturation start by inserting the negative value of the third- difference function of the current into the magnetisation curve of a CT. Thereafter, it calculates the core flux and then the corresponding magnetising current in conjunction with the magnetisation curve. The calculated magnetising current is added to the measured secondary current to obtain the correct secondary current. The algorithm can estimate the correct current irrespective of the level of the remanent flux. In the proposed busbar protection scheme, a current differential relay with the single-slope operating characteristic is used on the basis of the compensated current of the saturated CT. Test results indicate that the relay shows satisfactory performance for the various external and internal faults with CT saturation, particularly in the case of a progressive fault from a feeder fault to a busbar fault. The algorithm is implemented in a prototype relay based on a digital signal processor. The relay achieves greater stability on external faults, enhanced sensitivity on internal faults and fast operation on internal faults with CT saturation.</P>

전기버스 운영에 따른 경제성 평가

강유리(Yuri Kang),정문선(Moonseon Jeong),장영학(Younghak Chang),박태식(Taesik Park),문채주(Chaejoo Moon) 한국신재생에너지학회 2016 한국신재생에너지학회 학술대회논문집 Vol.2016 No.11

병렬형 전압원 능동필터의 성능개선

강유리(Yuri Kang),김원호(Wonho Kim),임근희(Geunhie Rim) 대한전기학회 1994 대한전기학회 학술대회 논문집 Vol.1994 No.7

도정 유무에 따른 제주산 보리의 항산화 활성 비교

강유리(Yuri Kang),김현정(Hyun Jung Kim) 한국식품과학회 2021 한국식품과학회지 Vol.53 No.3

본 연구에서는 제주산 쌀보리인 일반보리, 청보리, 흑보리를 이용하여 도정 유무에 따른 항산화 성분과 활성을 비교하였다. 제주산 쌀보리의 항산화 성분인 총 폴리페놀 함량은 도정하지 않은 쌀보리에서 139.99-149.90 μg GAE/g, 도정한 쌀보리는 91.14-125.45 μg GAE/g 범위로 나타나 도정하지 않은 쌀보리에서 보다 높은 총 폴리페놀 함량을 보였다. 또한 총 플라보노이드 함량도 도정하지 않은 쌀보리(0.89-1.01 μg QE/g)가 도정한 쌀보리(0.50-0.54 μg QE/g)보다 높은 함량을 나타내었다. HPLC로 분석한 제주산 쌀보리의 페놀성 화합물로 gallic, protocatechuic, vanillic, pcoumaric 및 ferulic acid가 주로 검출되었으며, 도정하지 않은 흑보리와 도정한 일반보리에서는 p-coumaric acid는 검출되지 않았다. Tocopherols 및 tocotrienols 분석 결과에서는 8가지 이성체 중 α-T3 함량이 높았고, 도정하지 않은 쌀보리의 α-T3는 20.68-33.09μg/g으로 도정한 쌀보리 8.93-14.98 μg/g보다 유의적으로 높게 검출되었다. 제주산 쌀보리의 in vitro 항산화 활성 결과에서 금속이온 제거능을 제외하고 도정하지 않은 쌀보리가 높은 항산화 활성을 나타내었고, 항산화 활성 중 SOD 소거 활성이 높게 나타내었다. In vitro 항산화 활성은 총 폴리페놀 및 총 플라보노이드 함량에 비해 총 tocopherols 및 tocotrienols 함량에 더 높은 상관관계를 보였다. 따라서 도정하지 않은 제주산 쌀보리에서 높은 항산화 성분 및 활성이 나타나 이를 천연 항산화제로 활용 가능할 것이라 생각된다. Barley contains health-beneficial compounds, such as phenolic acids, flavonoids, lignans, and tocopherols. The antioxidant activities of pearled and wholegrain hull-less, premature, and black barley harvested in Jeju were investigated by measuring total phenolic content (TPC), total flavonoid content (TFC), phenolic compounds, tocopherols (T), and tocotrienols (T3), along with their in vitro antioxidant activities. Consequently, TPC and TFC in wholegrain barley groups were higher than those in pearled barley. Gallic acid (1.55-2.98 μg/g) and protocatechuic acid (0.67-2.84 μg/g) were the predominant phenolic compounds in barley. Total T and T3 concentrations of wholegrain barley groups were significantly higher than those of pearled barley (p<0.05). Except for the metal chelating effect and reducing power, the in vitro antioxidant activities of wholegrain barley were significantly higher than those of pearled barley. These results indicate that wholegrain Jeju barley can be used as a natural antioxidant source in the food industry.

부부가족상담사의 원가족 경험이 상담사 발달 수준에 미치는 영향: 수퍼바이저와의 작업동맹 경험과 자기성찰의 매개효과

강유리(Yuri Kang),오제은(Jay Oh),김혜진(Hye Jin Kim),박은아(Euna Park) 사단법인 한국부부가족상담협회 2023 부부가족상담연구 Vol.4 No.1

This study aimed to empirically investigate the mediating effects of couple and family therapist’s working alliance experience with supervisors and self-reflection on the relationship between their family-of-origin experiences and therapist development. A total of 216 couple and family therapists participated in this study and structural equation modeling and bootstrapping techniques were utilized for data analysis. This study found that the family-of-origin experience of couple and family therapists had a direct effect on the path between working alliance experience with supervisors and self-reflection. Also, the working alliance experience of the couple and family therapists with supervisors revealed a direct effect on the path to self-reflection. In addition, the working alliance experience of the couple and family therapists with the supervisor exhibited a direct effect on the path to self-reflection. Based on the results of this study, the significance and limitations were discussed and suggestions were made for future studies.

능동필터 겸용 무정전 전원장치

강유리(Yuri Kang),김원호(Wonho Kim),김종수(Jongsoo Kim),임근희(Geunhie Rim) 대한전기학회 1994 대한전기학회 학술대회 논문집 Vol.1994 No.7

Integrative Approach toward Uncovering the Origin of Photoluminescence in Dual Heteroatom-Doped Carbon Nanodots

Choi, Yuri,Kang, Byungkyun,Lee, Jooyong,Kim, Sunghu,Kim, Gyeong Tae,Kang, Hyunju,Lee, Bo Ram,Kim, Hajin,Shim, Sang-Hee,Lee, Geunsik,Kwon, Oh-Hoon,Kim, Byeong-Su American Chemical Society 2016 Chemistry of materials Vol.28 No.19

<P>The pursuit of exceptionally high photoluminescence (PL) and stability is critical in the development of novel fluorophores for use in challenging bioimaging and optoelectronic devices. Carbon nanodots (CDs) doped with heteroatoms provide a particularly attractive means of effectively tailoring their intrinsic properties and exploiting new phenomena. Here, we report a one-step, scalable synthesis of boron-and-nitrogen co-doped CD (BN-CD) with outstanding optical properties unlike those of nitrogen-doped CD (N-CD) in solid state as well as solution. The detailed mechanistic framework was explored using a series of spectroscopic analyses and ultrafast spectroscopy coupled with density functional theory calculations, which all conclusively confirmed that the presence of more graphitic structures in the core and well-distributed surface states are responsible for the enhanced PL in BN-CD. Furthermore, single-molecule spectroscopy analysis demonstrated that a single BN-CD shows higher PL intensity and enhanced photobleaching time. We anticipate that this study will aid in uncovering the full potential of CDs in various fields.</P>

State of Forests and Biodiversity Conservation in Primorsky Krai, Russian Far East

( Yuri Ivanovich Man`ko ),( Don Koo Lee ),( Ho Sang Kang ),( Batkhuu Nyam Osor ) 한국산림과학회 2004 한국산림과학회지 Vol.93 No.6

N/A The vegetation and species composition of Primorsky Krai located in the Russian Far East are very similar to those in the Korean Peninsula and Northeastern part of China. The forests in Zapovednik(a strictly protected federal nature reserve) are unique old-growth forests without human disturbances for more than 500 years. The objectives of this study were to identify the forest resources and to understand the strategies for conservation of biodiversity and sustainable forest ecosystem management in Primorsky Krai. The total forestland comprises 11,833.3 thousand ha and is classified into 3 botanical-geographical zones; coniferous forest, coniferous-broadleaved mixed forest and forest-steppe. The total stock volume is estimated at 1,752 million ㎥, of which 66% are made up of conifers such as Picea jezoensis, Abies nephrolepis, Pinus koraiensis and Larix species. The flora contains 2,589 vascular plants and the forest plays important roles in the distribution and conservation of wildlife. The strategies for biodiversity conservation are as follows: 1) To conserve endemic and rare species of plant and wildlife with special protection, 2) To preserve the unique and original forest ecosystem without any industrial and human activities, and 3) To develop the sustainable uses and management of forest resources. The cooperative researches among Northeast Asian countries shall provide more detailed information not only on species distribution but on its biological and ecological characteristics.