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      • KCI등재

        파 에너지 (자외선, 초음파)/과황산나트륨을 이용한 이부프로펜 분해특성 연구

        나승민 ( Seung Min Na ),안윤경 ( Yungyong Ahn ),손영규 ( Ming Can Cui ),김지형 ( Young Gu Son ),( Jeeh Yeong Kim ) 한국환경과학회 2014 한국환경과학회지 Vol.23 No.5

        In this study, ibuprofen(IBP) degradation by the photochemical (UV/S2O82-) and sonochemical (US/S2O82-) processes was examined under various parameters, such as UV (10~40±5 W/L) and US (50~90±5 W/L) power density, optimum dosage of persulfate ion (S2O82-), temperature (20~60℃) and anions effect (Cl-, HCO3-, CO32-). The pseudo?first?order degradation rate constants were in the order of 10-1 to 10-5 min-1 depending on each processes. The synergistic effect of IBP degradation in UV/S2O82- and US/S2O82- processes could investigated, due to the generation of SO4- radical. This result can confirm from the produced H2O2 and SO42- concentration in each processes. IBP degradation rate affected by the S2O82- dosage, temperature, power and anion existence parameters. In particular, IBP degradation rate increased with the increase of the temperature (60℃) and applied power density (UV:40±5 W/L, US:90±5 W/L). On the other hand, anions effect on the IBP degradation was negative, due to the anion play as a the scavenger of radical.

      • KCI등재

        초음파 (US)와 다양한 파장범위의 자외선 (UV) 조사에 따른 DEP 분해특성에 관한 연구

        나승민 ( Seung Min Na ),( Jin Hua Cai ),신동훈 ( Dong Hoon Shin ),( Ming Can Cui ),김지형 ( Jee Hyeong Khim ) 한국환경과학회 2012 한국환경과학회지 Vol.21 No.7

        Diethyl phthalate (DEP) is widely spread in the natural environment as an endocrine disruption chemicals (EDs). Therefore, in this study, ultrasound (US) and ultraviolet (UVC), including various applied power density (10-40 W/L), UV wavelengths (365 nm, 254 nm and 185 nm) and frequencies (283 kHz, 935 kHz) were applied to a DEP contaminated solution. The pseudo-first order degradation rate constants were in the order of 10-1 to 10-4 min-1 depending on the processes. Photolytic and sonophotolytic DEP degradation rate also were high at shortest UV wavelength (VUV) due to the higher energy of photons, higher molar absorption coefficient of DEP and increased hydroxyl radical generation from homolysis of water. Sonolytic DEP degradation rate increased with increase of applied input power and the dominant reaction mechanism of DEP in sonolysis was estimated as hydroxyl radical reaction by the addition of t-BuOH, which is a common hydroxyl radical scavenger. Moreover, synergistic effect of were also observed for sonophotolytic degradation with various UV irradiation.

      • KCI등재

        수지상세포의 방사선 저항성에 대한 연구

        김은실,김종순,이명호,범희승,민정준,정환정,김성민,허영준,송호천,이제중 대한핵의학회 2003 핵의학 분자영상 Vol.37 No.3

        목적 : 림프구와 비교되는 수지상 세포의 방사선 민감성을 보기 위하여 본 연구를 시행하였다. 대상 및 방법 : 말초혈액에서 분리한 T 림프구에 0 Gy, 10 Gy, 30 Gy의 방사선을 조사하고 4시간 후에 유세포 분석기를 이용하여 선량별 세포고사 빈도를 관찰하였다. 또한 조혈모세포에서 미성숙 및 성숙 수지상 세포를 단계적으로 분리 배양하여 각각 0 Gy, 10 Gy, 30 Gy, 100 Gy의 방사선을 조사하고 4시간, 24시간 그리고 48 시간 후에 선량별 세포고사 빈도를 관찰하였다. 사이토스핀(cytospin)슬라이드에 림프구와 미성숙 및 성숙 수지상세포를 3×104개 씩 분주하고 May Grunwald-Giemsa 염색한 후, 광학 현미경 하에서 각각의 세포군 당 100개의 세포에서 세포 면적당 핵의 면적 비를 측정하였다. 결과 : 림프구에서는 방사선조사 선량별로 세포고사 빈도가 유의하게 증가하였으나, 수지상 세포에서는 그 분화정도나 방사선조사 선량에 따른 세포고사의 빈도차이가 없었다. 또한 수지상 세포는 방사선선량과 관계없이 용량에 의존적으로 강력한 T-세포 자극능을 보였다. 림프구의 세포에 대한 핵의 면적 비는 미성숙 및 성숙 수지상세포의 세포에 대한 핵의 면적 비보다 현저히 큰 반면, 두 가지 수지상세포간에 유의한 차이는 없었다. 결론 : 수지상세포는 그 분화도와 상관없이 림프구에 비하여 방사선 저항성을 나타내었고, 이는 세포의 형태적 차이에 따른 표적의 크기와 관련이 있을 것으로 생각되며, 향후 분자 생물학적인 연구의 기초 자료로 활용할 수 있을 것으로 생각된다. Purpose : To evaluate radiation sensitivity of dendritic cells in comparison with lymphocytes. Materials and methods : T lymphocytes captured from peripheral blood were irradiated by 0 Gy, 10 Gy, 30Gy. Apoptosis was measured by flowcytometry for staining of Annexin V 4 hours after irradiation. Immature and mature dendritic cells processed from blood hematopoietic stern cell were irradiated by 0 Gy, 10 Gy, 30 Gy, 100 Gy respectively and apoptosis was measured by flowcytometry with time difference as 4h, 24h and 48h after irradiation. Morphometric analysis by percent nucleus was measured in three cell groups, also. Results : Lymphocytes showed radiation sensitivity by increasing apoptotic fraction according to radiation dose. However, both mature and immature dendritic cells showed consistent fraction of apoptosis in spite of increasing radiation dose. Percent nucleus ratio is significantly higher in lymphocytes than that of mature or immature dendritic cells. Stimulation of T-cell by dendritic cells was not changed after irradiation. Conclusion : Dendritic cells showed radioresistance which was associated with small size of nucleus in comparison with lymphocytes and this result would be used as a basal data of radio-labelling for the cellular trafficking studies in nuclear medicine fields.

      • KCI등재

        물리학 선량법을 이용한 갑상선암의 개인별 최대안전용량 I-131 치료법 개발과 유용성 평가

        김정철,윤정한,범희승,제갈영종,송호천,민정준,정환정,김성민,허영준,이명호,박영규,정준기 대한핵의학회 2003 핵의학 분자영상 Vol.37 No.2

        목적 : 분화갑상선암 환자에 대한 방사성옥소(I-131) 치료는 재발율과 사망률을 감소시키는 효과적인 치료법이지만, 치료용량을 증가시킴으로써 치료율을 향상시킬 수 있는지에 대해서는 아직 논란이 있다. 본 연구에서는 최대허용선량 치료법의 효용성을 검증하고자 하였다. 대상 및 방법 : 임상적 병기가 제3, 4병기이고, 6개월 이후에 I-131 전신스캔(이하 IWBS)과 혈중 thyroglobulin (이하 Tg), anti-thyroglobulin antibody (이하 ATA), 초음파검사 (이하 US) 및 F-18 FDG PET 등을 통해 치료여부를 확인할 수 있었던 58명(남:여=9:49, 평균연령 50±11세)의 유두상갑상선암 환자를 대상으로 하였다. 이중 11명은 제4병기, 47명은 제3병기였으며, 43명(남:여=4:39), 평균연령 50±11세)은 7.4 GBq 이하의 고식적인 저용량치료법으로 치료하였고, 9.25 GBq 이상의 고용량 치료를 받은 환자는 15명(남:여=5:10, 평균연령 50±12세)으로 고용량군에서 남자가 더 많았으나 연령의 차이는 없었다. 고용량군 환자 모두에서 추적용량의 방사성옥소(평균 77±3 MBq)를 경구 투여한 후 혈중 방사능소실곡선을 통해 최대허용선량(maximum permissible dose, 이하 MPD)을 계산하였으며, 7명에서는 말초혈액림프구의 중기염색체분석법에 의해 생물학적으로 MPD를 계산하였다. 14명에서는 치료용량의 방사성옥소를 투여한 후 혈중 방사능소실곡선을 통해 MPD를 계사하였다. 완전치유(complete response, 이하 CR)는 IWBS에서 병소가 없어지고, 혈중 Tg치가 1 ng/mL 이하로 감소한 경우로 정의하였으며, 부분치유(partial response, 이하 PR)는 IWBS에서 병소가 없어졌더라도 혈중 Tg, ATA치가 높거나, US 또는 PET 검사에서 병소가 남아있는 경우로 정의하였다. 치료후 IWBS에서 병소가 오히려 증가하거나 변함없는 경우는 없었다. 방사성옥소 치료에 의한 부작용은 입원기간 중 타액선이 현저하게 붓고 통증이 있거나, 구토를 심하게 하는 경우, 그리고 퇴원후 1개월째 백혈구수가 20% 이상 감소한 경우로 정의하였다. 결과 : 양 군간에 연속적인 수치변화를 비교하는 경우는 paired t-test를 이용하였으며, 대상군간 치료효과와 부작용의 비교는 chi-square test를 이용하였다. p값 0.05 미만을 통계적으로 유의한 차이로 인정하였다. 고용량군 환자 모두에서 추적용량과 치료용량의 방사성옥소 투여 후 혈액의 피폭선량은 각각 0.012±0.3 Gy, 1.66±25 Gy였으며, 방사성옥소 투여 후 혈액에 전달되는 피폭선량은 추적용량보다 치료용량에서 더 많았고 (1.21: 166 rad, p<0.001), 방사성옥소 1 mCi당 혈액에 전달되는 피폭선량은 차이가 없었다(0.58±0.1 vs. 0.56±0.1 rad/37 MBq, p=0.34). 추적용량 방사성옥소 투여 후 구한 MPD는 평균 13.3±1.9 GBq (9.7 ~ 16 GBq) 이였고, 치료용량 방사성옥소 투여 후 구한 MPD는 평균 13.8±2.1 GBq (10.4 ~ 16.3 GBq)로 유의한 차이가 없었으며 (p=0.20), 두 수치간에는 유의한 상관 관계가 있었다(r=0.8, p<0.0001). 7명의 환자에서 말초혈액림프구 중기염색체 분석법으로 MPD를 측정하였는데 혈액의 피폭선량은 1.78±0.03 G였으며, 같은 환자에서 혈중 방사능소실곡선으로부터 구한 피폭선량은 1.54±0.03 G로 유의하게 낮았으나 (p=0.01), 두 측정치 간에는 유의한 상관관계(r=0.86, p=0.01)가 있었다. 저용량 치료군 43명 중 22명(51.2%)에서 완전치유를 보였고 21명(48.8%)에서는 부분치유를 보인 반면 고용량 치료군 15명 중 12명(80%)에서 완전치유를 보였고 3명(20%)에서만 부분치유를 보여 고용량 치료군에서 유의하게 높은 완전치유를 얻을 수 있었다(p=0.05). 한편 부작용 발생빈도는 저용량 치료군 43명 중 13(30.2%), 고용량 치료군 15명 중 6명(40%)로 양군간에 유의한 차이가 없었다(p=0.46). 임상적인 병기, 연령 및 성별에 따라서는 치유의 차이가 없었다(p>0.05). 결론 : 혈중소실곡선으로부터 MPD를 결정하고 이를 토대로 환자 개개인별로 적절한 선량을 선택하여 치료하는 방법은 부작용을 최소화하면서도 치료효과를 높일 수 있는 매우 유용한 치료법이며, 고위험군 분화갑상선 암 환자에게 가장 적절한 치료법이라고 사료되었다. Purpose: Radioiodine (1-131) therapy is an effective modality to reduce both recurrence and mortality rates in differentiated thyroid cancer. Whether higher doses shows higher therapeutic responses was still debatable. The purpose of this study was to validate curve-fitting (CF) method measuring maximum permissible dose (MPD) by a biological dosimetry using metaphase analysis of peripheral blood lymphocytes. Materials and Methods: Therapeutic effects of MPD was evaluated in 58 patients (49 females and 9 males, mean age 50±11 years) of papillary thyroid cancer. Among them 43 patients were treated with ≤7.4 GBq, while 15 patients with ≥9.25 GBq. The former was defined as low-dose group, and the latter high-dose group. Therapeutic response was defined as complete response when complete disappearance of lesions on follow-up 1-131 scan and undetectable serum thyroglobulin levels were found. Statistical comparison between groups were done using chi-square test. P value less than 0.05 was regarded as statistically significant. Results: MPD measured by CF method using tracer and therapeutic doses were 13.3±1.9 and 13.8±2.1 GBq, respectively (p=0.20). They showed a significant correlation (r=0.8, p<0.0001). Exposed doses to blood measured by CF and biological methods were 1.54±0.03 and 1.78±0.03 Gy (p=0.01). They also showed a significant correlation (r=0.86, p=0.01). High-does group showed a significantly higher rate of complete response (12/15, 80%) as compared to the low-dose group (22/43, 51.2%) (p=0.05). While occurrence of side effects was not different between two groups (40% vs. 30.2%, p=0.46). Conclusion: Measurement of MPD using CF method is reliable, and the high-dose 1-131 therapy using MPD gains significantly higher therapeutic effects as compared with low-dose therapy.

      • KCI등재

        Model Prediction Control Design for Inverse Multiplicative Structure Based Feedforward Hysteresis Compensation of a Piezo Nanopositioning Stage

        Min Ming,Jie Ling,Zhao Feng,Xiaohui Xiao 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.11

        The inherent hysteresis nonlinearity of piezoelectric actuators seriously deteriorates the tracking performance of piezo-actuated nanopositioning stage, especially in large stroke applications. Usually, the model of piezo-actuated stage is given by cascading a rateindependent hysteresis submodel with a linear dynamics submodel. This paper develops a composite model predictive control (MPC) with feedforward hysteresis compensation based on the inverse multiplicative structure. The feedforward controller has the merit of non-inverse requirement. The linear MPC is utilized as a feedback controller with the feature of simple solution for the feedforward compensation system. Experimental tracking results of sinusoidal signals at different frequencies as well as complex signals show that the proposed method can improve the tracking performance of the piezo-actuated stage, verifying its effectiveness.

      • KCI등재

        HMGB1 regulates autophagy through increasing transcriptional activities of JNK and ERK in human myeloid Leukemia cells

        ( Ming Yi Zhao ),( Ming Hua Yang ),( Liang Chun Yang ),( Yan Yu ),( Min Xie ),( Shan Zhu ),( Rui Kang ),( Dao Lin Tang ),( Zhi Gang Jiang ),( Wu Zhou Yuan ),( Xiu Shan Wu ),( Li Zhi Cao ) 생화학분자생물학회(구 한국생화학분자생물학회) 2011 BMB Reports Vol.44 No.9

        HMGB1 is associated with human cancers and is an activator of autophagy which mediates chemotherapy resistance. We here show that the mRNA levels of HMGB1 are high in leukemia cells and it is involved in the progression of childhood chronic myeloid leukemia (CML). HMGB1 decreases the sensitivity of human myeloid leukemia cells K562 to anti-cancer drug induced death through up-regulating the autophagy pathway, which is confirmed by the observation with an increase in fusion of autophagosomes and autophagolysosomes. When overexpressing HMGB1, both mRNA levels of Beclin-1, VSP34 and UVRAG which are key genes involved in mammalian autophagy and protein levels of p-Bcl-2 and LC3-II are increased. Luciferase assays document that over-expression of HMGB1 increases the transcriptional activity of JNK and ERK, which may be silenced by siRNA. The results suggest that HMGB1 regulates JNK and ERK required for autophagy, which provides a potential drug target for therapeutic interventions in childhood CML. [BMB reports 2011; 44(9): 601-606]

      • Surfactant-Assisted Synthesis of Fe<sub>2</sub>O<sub>3</sub> Nanoparticles and F-Doped Carbon Modification toward an Improved Fe<sub>3</sub>O<sub>4</sub>@CF<sub><i>x</i></sub>/LiNi<sub>0.5</sub>Mn<sub>1.5</sub>O<sub>4</sub> Battery

        Ming, Hai,Ming, Jun,Oh, Seung-Min,Tian, Shu,Zhou, Qun,Huang, Hui,Sun, Yang-Kook,Zheng, Junwei American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.17

        <P>A simple surfactant-assisted reflux method was used in this study for the synthesis of cocklebur-shaped Fe<SUB>2</SUB>O<SUB>3</SUB> nanoparticles (NPs). With this strategy, a series of nanostructured Fe<SUB>2</SUB>O<SUB>3</SUB> NPs with a size distribution ranging from 20 to 120 nm and a tunable surface area were readily controlled by varying reflux temperature and the type of surfactant. Surfactants such as cetyltrimethylammonium bromide (CTAB), polyvinylpyrrolidone (PVP), poly(ethylene glycol)-<I>block</I>-poly(propylene glycol)-<I>block</I>-poly(ethylene glycol) (F127) and sodium dodecyl benzenesulfonate (SDBS) were used to achieve large-scale synthesis of uniform Fe<SUB>2</SUB>O<SUB>3</SUB> NPs with a relatively low cost. A new composite of Fe<SUB>3</SUB>O<SUB>4</SUB>@CF<SUB><I>x</I></SUB> was prepared by coating the primary Fe<SUB>2</SUB>O<SUB>3</SUB> NPs with a layer of F-doped carbon (CF<SUB><I>x</I></SUB>) with a one-step carbonization process. The Fe<SUB>3</SUB>O<SUB>4</SUB>@CF<SUB><I>x</I></SUB> composite was utilized as the anode in a lithium ion battery and exhibited a high reversible capacity of 900 mAh g<SUP>–1</SUP> at a current density of 100 mA g<SUP>–1</SUP> over 100 cycles with 95% capacity retention. In addition, a new Fe<SUB>3</SUB>O<SUB>4</SUB>@CF<SUB><I>x</I></SUB>/LiNi<SUB>0.5</SUB>Mn<SUB>1.5</SUB>O<SUB>4</SUB> battery with a high energy density of 371 Wh kg<SUP>–1</SUP> (vs cathode) was successfully assembled, and more than 300 cycles were easily completed with 66.8% capacity retention at 100 mA g<SUP>–1</SUP>. Even cycled at the high temperature of 45 °C, this full cell also exhibited a relatively high capacity of 91.6 mAh g<SUP>–1</SUP> (vs cathode) at 100 mA g<SUP>–1</SUP> and retained 54.6% of its reversible capacity over 50 cycles. Introducing CF<SUB><I>x</I></SUB> chemicals to modify metal oxide anodes and/or any other cathode is of great interest for advanced energy storage and conversion devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-17/am504144d/production/images/medium/am-2014-04144d_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am504144d'>ACS Electronic Supporting Info</A></P>

      • High-Speed PIV Evaluation of Fuel Sprays under Superheated Conditions

        ( Ming Zhang ),( Min Xu ),( Yu Yin Zhang ),( Gao Ming Zhang ) 한국액체미립화학회 2010 한국액체미립화학회 학술강연회 논문집 Vol.2010 No.-

        Spray structure, distribution, and atomization process of the superheated sprays are dramatically influenced by the degree of the fuel superheating. The fuel spray flow field can provide detailed information about such influence due to the fuel superheating. It is anticipated that the fuel spray flow field depends on the superheat degree, which is carefully examined using high-speed PIV in this study. The fuel droplet velocities are measured within the lower number density regions of the spray generated from a multi-hole injector. The spray structure is characterized by spray penetration, maximum spray width and spray angle derived from the spray laser-sheet images. These characteristics are correlated with the spray velocity vector field to analyze the driving force of the spray transformation. The results illustrate that, as the superheat degree increases, the spray velocities in both radial and axial directions vary dramatically accompanied by the unexpected transformations of the spray structure, such as transforming from separate plumes to a collapsed form. The superheat degree is the predominant factor influencing break-up, atomization, and structure of the superheated sprays.

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