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Radiotherapy Technique of High Energy Electron (고에너지 전자선의 방사선 치료 기술)

  • SUH M.W.;PARK J.I.;CHOI H.S.;KIM W.Y.
    • The Journal of Korean Society for Radiation Therapy
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    • v.1 no.1
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    • pp.63-69
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    • 1985
  • High energy electron beams took effect for tumor radio-therapy, however, had a lot of problems in clinical application because of various conversion factors and complication of physical reactions. Therefore, we had experimentally studied the important properties of high energy electron beams from the linear accelerator, LMR-13, installed in Yonsei Cancer Center. The results of experimental studies on the problems in the 8, 10, 12 Mev electron beam therapy were reported as following. 1. On the measurements of the outputs and absorbed does, the ionization type dosimeters that had calibrated by $^{90}Sr$ standard source were suitable as under $3\%$ errors for high energy electrons to measure, but measuring doses in small field sizes and the regions of rapid fall off dose with ionization chambers were difficult. 2. The electron energy were measured precisely with energy spectrometer consisted of magnet analyzer and tele-control detector and the practical electron energy was calculated under $5\%$ errors by maximum range of high energy electron beam in the water. 3. The correcting factors of perturbated dose distributions owing to radiation field, energy and material of the treatment cone were checked and described systematically and variation of dose distributions due to inhomogeneous tissues and sloping skin surfaces were completely compensated. 4. The electron beams, using the scatters; i.e., gold, tin, copper, lead, aluminium foils, were adequately diffused and minimizing the bremsstrahlung X-ray induced by the electron energy, irradiation field size and material of scatterers, respectively. 5. Inproving of the dose distribution from the methods of pendulum, slit, grid and focusing irradiations, the therapeutic capacity with limited electron energy could be extended.

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Evaporative Self-Assembly of Single-Walled Carbon Nanotubes for Field Effect Transistor (용매증발기반 자기조립을 이용한 단일벽 탄소나노튜브 정렬 및 트랜지스터 응용)

  • Kang, Seok Hee;Jeong, Do Young;Eom, Seong Un;Hwang, Cheong Seok;Hong, Suck Won
    • Korean Journal of Materials Research
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    • v.23 no.8
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    • pp.453-461
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    • 2013
  • Controlling the stick and slip motions of the contact lines in a confined geometry comprised of a spherical lens with a flat substrate is useful for manufacturing polymer ring patterns. We used a sphere on a flat geometry, by which we could control the interfaces of the solution, vapor and substrate. By this method, hundreds of concentric ring-pattern formations of a linear conjugated polymer, poly [2-methoxy-5-(2-thylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), were generated with excellent regularity over large areas after complete solvent evaporation. Subsequently, the MEH-PPV ring patterns played a role as a directed template to organize highly regular concentric rings of single-walled carbon nanotubes(SWCNTs); when a droplet of the SWCNT suspension in water was casted onto the prepared substrate, hydrophobic polymer patterns confined the water dispersed SWCNTs in between the hydrophilicized $SiO_2/Si$ substrate. As the solvent evaporated, SWCNT-rings were formed in between MEH-PPV rings with controlled density. Finally, we used a lift-off process to produce SWCNT patterns by the removal of a sacrificial polymer template with organic solvent. We also fabricated a field effect transistor using self-assembled SWCNT networks on a $SiO_2/Si$ substrate.

Relations of Serum Visfatin and Resistin Levels with Endometrial Cancer and Factors Associated with its Prognosis

  • Ilhan, Tolgay Tuyan;Kebapcilar, Aysegul;Yilmaz, Setenay Arzu;Ilhan, Turkan;Kerimoglu, Ozlem Secilmis;Pekin, Aybuke Tazegul;Akyurek, Fikret;Unlu, Ali;Celik, Cetin
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.11
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    • pp.4503-4508
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    • 2015
  • Background: The aims of this study were compare the serum visfatin and resistin levels between endometrial cancer (EC) patients and controls and evaluate their power to predict prognosis. Materials and Methods: This prospective study was conducted between March 2013 to June 2014 on the Gynecologic Oncology Department of the University of Selcuk, Konya, Turkey. A total of 42 EC patients and 42 controls were included and assessed for differences in serum visfatin and resistin levels, along with prognostic factors. Results: Endometrial cancer patients had significantly higher visfatin levels than control s (p: 0.011), associated with deep myometrial invasion (p: 0.019). In contrast the serum level of resistin did not significantly differ between EC patients and controls (p: 0.362). However, high resistin level in EC patients was associated with increase lymph node metastasis (p: 0.009). On logistic regression analysis, we found that serum visfatin elevation was associated with risk of myometrial invasion (OR: 1,091; 95%CI: 1.021-1.166; p: 0.010) and serum resistin with risk of lymph node metastasis (OR: 1.018; 95%CI: 1.000-1.035; p: 0.046). For myometrial invasion prediction, a serum visfatin level greater than 26.8 ng/mL demonstrated a sensitivity and specificity of 66.6 % and 96.4%, respectively. For lymph node metastasis prediction, the best cut-off for serum resistin level was 599ng/mL. A serum resistin level greater than this demonstrated a sensitivity and specificity of 87.5% and 77.1%, respectively. Conclusions: Our data suggest that serum visfatin is elevated in patients with EC and serum visfatin and resistin levels could be used to predict the risk of advance stage lesions.

Quality of Breast Cancer Early Detection Services Conducted by Well Woman Clinics in the District of Gampaha, Sri Lanka

  • Vithana, Palatiyana Vithanage Sajeewanie Chiranthika;Ariyaratne, M.A.Y.;Jayawardana, P.L.
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.75-80
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    • 2013
  • Background: Breast cancer is the most common cancer diagnosed in females in Sri Lanka and early detection can lead to reduction in morbidity and mortality. Aim: To evaluate selected aspects of breast cancer early detection services implemented through well woman clinics (WWCs) in the Gampaha District. Methods: The study consisted of two components. A retrospective descriptive arm assessed clinical breast examination (CBE) coverage of target age group women (TGW) of 35-59 years in all the WWCs in Gampaha district over 2003-2007. A cross sectional descriptive study additionally assessed quality of breast cancer early detection services. The Lot Quality Assurance Sampling (LQAS) technique was used to decide on the lot size and threshold values, which were computed as twenty and six clinics. Checklists were employed in assessing coverage, physical facilities and clinic activities. Client satisfaction on WWC services was assessed among 200 TGW attending 20 WWCs using an interviewer-administered questionnaire. Results: CBE coverage in the Gampaha district increased only from 1.1-2.2% over 2003-2007. With regard to physical facilities, the number of clinics that were rated substandard varied between 7-18 (35-90%). The items that were lacking included dust bins, notice boards, stationary, furniture and linen, and cleanliness of outside premises and toilets. With regard to clinic activities, punctuality of staff, late commencement of clinics, provision of health education, supervision, CBE and breast self-examination (BSE) were substandard in 7-20 clinics (35-100%). Client satisfaction for WWC services was 45.2% (IQR: 38.7-54.8%) and only 11% had a score of ${\geq}70%$, the cut off set for satisfaction. Conclusions: Breast cancer early detection service coverage in the Gampaha district remained low (2.2%) in 2007, 11 years after commencing WWCs. All 20 clinics were substandard for overall CBE and BSE.

User Association and Base Station Sleep Management in Dense Heterogeneous Cellular Networks

  • Su, Gongchao;Chen, Bin;Lin, Xiaohui;Wang, Hui;Li, Lemin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.4
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    • pp.2058-2074
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    • 2017
  • Dense Heterogeneous Cellular Networks(HCNs) offer a promising approach to meet the target of 1000x increase in aggregate data rates in 5G wireless communication systems. However how to best utilize the available radio resources at densely deployed small cells remains an open problem as those small cells are typically unplanned. In this paper we focus on balancing loads across macro cells and small cells by offloading users to small cells, as well as dynamically switching off underutilized small cells. We propose a joint user association and base station(BS) sleep mangement(UA-BSM) scheme that proactively offloads users to a fraction of the densely deployed small cells. We propose a heuristic algorithm that iteratively solves the user association problem and puts BSs with low loads into sleep. An interference relation matrix(IRM) is constructed to help us identify the candidate BSs that can be put into sleep. User associations are then aggregated to selected small cells that remain active. Simulation results show that our proposed approach achieves load balancing across macro and small cells and reduces the number of active BSs. Numerical results show user signal to interference ratio(SINR) can be improved by small cell sleep control.

Design and Implementation of Standby Power Cutoff System for Smart Home Environment Based on Zigbee-MQTT (Zigbee-MQTT 기반 스마트 홈 환경에 적합한 대기전력 차단 시스템 설계 및 구현)

  • Jang, Young-Hwan;Yang, Seung-Su;Park, Seok-Cheon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.4
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    • pp.129-135
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    • 2017
  • Recently, with the development of IoT technology, there has been an increase in interest in the power consumption of the devices used by the internal devices. Especially, the standby power consumption during the main function of the devices is about 11% of the power energy and the problem of standby power interruption is suggested. However, there is a problem that the plug must be unplugged in order to substantially shut off standby power. Therefore, in this paper, we design and implement a standby power cutoff algorithm that can automatically control and manage users' participation in order to solve there problems. As a result of evaluating the implemented system, it was confirmed that the standby power interruption rate improved by about 5.89Wh on average compared to the existing system.

Diagnostic Values of the Measurement of Fungiform Papillae in Patients with Burning Mouth Syndrome (구강작열감증후군 환자에서 심상유두 수 측정의 진단적 가치)

  • Lee, Eom-jee;Park, Jae-woo;Kim, Jin-sung
    • The Journal of Internal Korean Medicine
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    • v.37 no.6
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    • pp.978-989
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    • 2016
  • Objectives: This study evaluated the diagnostic values of measuring the number of fungiform papillae in patients with burning mouth syndrome (BMS). Methods: Seventy participants (35 BMS patients and 35 Healthy control) participated in this study. The number of fungiform papillae (FP) was measured on the anterior part of the tongue within an area of $9mm^2$ using a digital camera. The subjects were evaluated on their yin deficiency and blood stasis conditions using the Yin-Deficiency Questionnaire (YDQ) and Blood Stasis Questionnaire (BSQ). Moreover, the severities of subjective tongue pain in the BMS patients were assessed using Visual Analog Scale. Results: There were significant differences in the number of FP and the YDQ and BSQ scores between the two groups. The number of FP and the YDQ scores in the BMS group showed statistically significant correlations with the VAS score of tongue pain. In the bivariate logistic regression analysis, the factor that most strongly contributed to BMS was the number of FP. The optimal cut-off value of the number of fungiform papillae was calculated as 5.5 with 71.4% sensitivity and 82.9% specificity. There was no statistically significant correlation between the number of FP and the YDQ or BSQ score. Conclusions: According to these findings, measuring the number of FP could be a valuable evaluation indicator of BMS.

Effects of Psychrotrophic Bacteria, Serratia liquefaciens and Acinetobacter genomospecies 10 on Yogurt Quality

  • Shin, Yong Kook;Oh, Nam Su;Lee, Hyun Ah;Choi, Jong-Woo;Nam, Myoung Soo
    • Food Science of Animal Resources
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    • v.34 no.4
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    • pp.543-551
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    • 2014
  • The aim of this study was to evaluate the effect of proteolytic (Serratia liquefaciens, match %: 99.39) or lipolytic (Acinetobacter genomospecies 10, match %: 99.90) psychrotrophic bacteria (bacterial counts, analysis of free fatty acids (FFA) and analysis of free amino acids) on the microbial and chemical properties (yogurt composition), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of yogurt during storage. Yogurts were prepared with raw milk preinoculated with each psychrotrophic bacteria. The total solid, fat, and protein content were not affected by preinoculation, but the pH of yogurt preinoculated with psychrotrophic bacteria was higher than in control. There was a dramatic increase in short chain free fatty acids among FFA in yogurt with Acinetobacter genomospecies 10. For 14 d of cold storage condition, SCFFA was 25.3 mg/kg to 34.4 mg/kg (1.36 times increased), MCFFA was 20.4 mg/kg to 25.7 mg/kg (1.26 times increased), and LCFFA was 240.2 mg/kg to 322.8 mg/kg (1.34 times increased). Serratia liquefaciens (match %: 99.39) in yogurt caused a greater accumulation of free amino acids (FAA), especially bitter peptides such as leucine, valine, arginine, and tyrosine, but SDS-PAGE showed that the inoculation of Serratia liquefaciens did not affect the degree of casein degradation during storage. Taken together, the excessive peptides and FFA in yogurt generated from psychrotrophic bacteria could develop off-flavors that degrade the quality of commercial yogurt products.

Microarray and Quantitative PCR Analysis of Gene Expression Profiles in Response to Treatment with Tomato Leaf Extract in MCF-7 Breast Cancer Cells

  • Amid, Azura;Chik, Wan Dalila Wan;Jamal, Parveen;Hashim, Yumi Zuhanis Has-Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6319-6325
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    • 2012
  • We previously found cytotoxic effects of tomato leaf extract (TLE) on the MCF-7 breast cancer cell line. The aim of this study was to ascertain the molecular mechanisms associated with the usage of TLE as an anticancer agent by microarray analysis using mRNA from MCF-7 breast cancer cells after treatment with TLE for 1 hr and 48 hrs. Approximately 991 genes out of the 30,000 genes in the human genome were significantly (p<0.05) changed after the treatment. Within this gene set, 88 were significantly changed between the TLE treated cells and the untreated MCF-7 cells (control cells) with a cut-off fold change >2.00. In order to focus on genes that were involved in cancer cell growth, only twenty-nine genes were selected, either down-regulated or up-regulated after treatment with TLE. Microarray assay results were confirmed by analyzing 10 of the most up and down regulated genes related to cancer cells progression using real-time PCR. Treatment with TLE induced significant up-regulation in the expression of the CRYAB, PIM1, BTG1, CYR61, HIF1-${\alpha}$ and CEBP-${\beta}$ genes after 1 hr and 48 hrs, whereas the TXNIP and THBS1 genes were up-regulated after 1 hr of treatment but down-regulated after 48 hrs. In addition both the HMG1L1 and HIST2H3D genes were down-regulated after 1 hr and 48 hrs of treatment. These results demonstrate the potent activity of TLE as an anticancer agent.

A Packet Collision Avoidance Technique in IEEE1609.4 Based Time Synchronization Multi-channel Environment (IEEE1609.4 기반 시간 동기 멀티채널 환경에서의 패킷 충돌 회피 기법)

  • Jin, Seong-Keun;Lim, Ki-Taeg;Shin, Dae-Kyo;Yoon, Sang-Hun;Jung, Han-Gyun
    • Journal of IKEEE
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    • v.19 no.3
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    • pp.385-391
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    • 2015
  • In this paper, we analyze the communication performance in a time synchronous multi-channel environment and deal with a packet collision avoidance technique to improve it based on IEEE1609.4 for increasing the efficiency of the control channel IEEE802.11p WAVE communication system. In previous works, they tried to solve this problem by message scheduling method on application layer software or changing the value of the random back-off optionally Contention Window. In this paper, we propose a method for adjusting the Channel Guard Interval for packet collision avoidance. The performance was evaluated by the actual vehicle test. The result was confirmed performance over 90% PDR(Packet Delivery Ratio).