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The Effects of Intrapatient Variability in Tacrolimus Concentration on Clinical Outcomes Immediately After Liver Transplantation (Tacrolimus의 혈중농도 변동성이 간이식 예후에 미치는 영향)

  • Kim, Eunji;Kim, Boram;Cho, Jungwon;Lee, Jung Hwa;Lee, Eunsook;Yu, Yun Mi;Cho, Jai Young;Lee, Euni;Choi, YoungRok
    • Korean Journal of Clinical Pharmacy
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    • v.30 no.1
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    • pp.36-43
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    • 2020
  • Background: Tacrolimus, a calcineurin inhibitor, is an immunosuppressant used in post-transplantation maintenance therapy. The drug has a narrow therapeutic range and requires periodic therapeutic drug monitoring. Although many studies have reported the effects of intrapatient variability of tacrolimus on survival, rejection, and complications in renal transplant recipients, very few studies have reported these effects in liver transplant recipients. The purpose of this study was to evaluate the effect of intrapatient variability of tacrolimus on clinical outcomes after liver transplantation. Methods: Intrapatient variability was calculated using individual, averaged tacrolimus concentrations. Patients were divided into two groups according to their median variability value: high-variability and low-variability groups. The rate of deviation from the therapeutic range, incidence of acute rejection, post-transplant diabetes, incidence of infection, and estimated glomerular filtration rate (eGFR) after transplantation were compared between the groups. Results: Of the total patients (n=82), the high-variability group (n=41) exhibited significantly greater deviation from the therapeutic range (65.92% vs. 56.84%; p<0.001). There was no significant difference in acute rejection or post-transplantation diabetes incidence or eGFR; however, the number of infection in the first 6 months was significantly lower in the low-variability group (0.4 vs. 0.9 times; p=0.039). Multiple linear regression analysis showed that the number of infection significantly increased as intrapatient variability increased (p=0.015). Conclusion: High intrapatient variability in tacrolimus concentrations was strongly associated with an increased frequency of deviation from the suggested therapeutic range and an increased number of infection.

3D Measurement Method Based on Point Cloud and Solid Model for Urban SingleTrees (Point cloud와 solid model을 기반으로 한 단일수목 입체적 정량화기법 연구)

  • Park, Haekyung
    • Korean Journal of Remote Sensing
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    • v.33 no.6_2
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    • pp.1139-1149
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    • 2017
  • Measuring tree's volume is very important input data of various environmental analysis modeling However, It's difficult to use economical and equipment to measure a fragmented small green space in the city. In addition, Trees are sensitive to seasons, so we need new and easier equipment and quantification methods for measuring trees than lidar for high frequency monitoring. In particular, the tree's size in a city affect management costs, ecosystem services, safety, and so need to be managed and informed on the individual tree-based. In this study, we aim to acquire image data with UAV(Unmanned Aerial Vehicle), which can be operated at low cost and frequently, and quickly and easily quantify a single tree using SfM-MVS(Structure from Motion-Multi View Stereo), and we evaluate the impact of reducing number of images on the point density of point clouds generated from SfM-MVS and the quantification of single trees. Also, We used the Watertight model to estimate the volume of a single tree and to shape it into a 3D structure and compare it with the quantification results of 3 different type of 3D models. The results of the analysis show that UAV, SfM-MVS and solid model can quantify and shape a single tree with low cost and high time resolution easily. This study is only for a single tree, Therefore, in order to apply it to a larger scale, it is necessary to follow up research to develop it, such as convergence with various spatial information data, improvement of quantification technique and flight plan for enlarging green space.

A Study on the development of a decision model on free flow and congested traffic conditions to determine the optimal ventilation capacity in highway tunnels (고속도로 터널의 적정 환기용량 계획을 위한 원활 및 지체조건 판별모델 개발에 대한 연구)

  • Kim, Hyo-Gyu;Yoo, Ji-Oh;Lee, Chang-Woo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.4
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    • pp.375-395
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    • 2012
  • According to the local highway tunnel ventilation guideline, ventilation capacity calculation should be performed at the speed ranging from 10 km/h to 80 km/h. This is so reasonable method considering uncongested and congested traffic conditions in urban tunnels. But recently due to low traffic volume and very low congestion frequency in rural highway tunnels, it seems to be an inadequate way to apply the guideline. Therefore the calculation should be performed separately for the free flow and congested traffic cases classified by the appropriate decision model. This paper aims at determining unnecessary running speed range for reasonable tunnel ventilation design, considering free flow and congested traffic conditions. Firstly, traffic volumes in highway tunnels were collected and if any, the causes of congestion were investigated. And with concept of 'margin speed'($u-u_m$), the decision model on traffic congestion was developed. Applicability of the decision model was also analyzed with case study. According to the results, when design speed is 100 km/h, with V/C less than 0.1, then the range of unnecessary speed in tunnel ventilation design is less than 40 km/h; for $V/C{\leqq}0.35$, $V/C{\leqq}0.6$ and $V/C{\leqq}0.75$, the unnecessary speed ranges are found to be ${\leqq}30$, ${\leqq}20$ and ${\leqq}10km/h$, respectively.

Fabrication and characterization of the 0.25 ${\mu}m$ T-shaped gate P-HEMT and its application for MMIC low noise amplifier (0.25 ${\mu}m$ T형 게이트 P-HEMT 제작 및 특성 평가와 MMIC 저잡음 증폭기에 응용)

  • Kim, Byung-Gyu;Kim, Young-Jin;Jeong, Yoon-Ha
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.1
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    • pp.38-46
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    • 1999
  • o.25${\mu}m$ T-shaped gate P-HEMT is fabricated and used for design of X0band three stage monolithic microwave integrated circuit(MMIC) low noise amplifier(LNA). The fabricated P-HEMT exhibits an extrinsis transconductance of 400mS/mm and a drain current of 400mA/mm. The RF and noise characteristics show that the current gain cut off frequency is 65GHz and minimum noise figure(NFmin) of 0.7dB with an associated gain of 14.8dB at 9GHz. In the design of the three stage LNA, we have used the inductive series feedback circuit topology with the short stub. The effects of series feedback to the noise figure, the gain, and the stability have been investigated to find the optimal short stub length. The designed three staage LNA showed a gain of above 33dB, a noise figure of under 1.2dB, and ainput/output return loss of under 15dB and 14dB, respectively. The results show that the fabricated P-HEMT is very suitable for a X-band LNA with high gain.

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Cold Tolerance Assessment of Lagerstroemia indica and Pyracantha angustifolia with Dormant Branches (배롱나무와 피라칸사 겨울 휴면지의 내한성 평가)

  • Shin, Chang-Seob
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.6
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    • pp.118-125
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    • 2011
  • This study was conducted to check danger of the cold injury by reviewing the lowest temperature by regions and the cold tolerance of Lagerstroemia indica and Pyracantha angustifolia. The cold tolerance of the samples treated at low temperature was evaluated by measuring electrical conductivity and observing browning of the cambium. It was proved that the lethal temperature of L. indica is below $-17.1^{\circ}C$, and that of P. angustifolia is below $-18.9^{\circ}C$. The frequency of the lowest temperature went down below $-17.1^{\circ}C$, was 7 times in Daejeon, 55 times in Cheongju and 72 times in Suwon for the last 45 years. In Daejeon, it has happened only once since 1975. The temperature dropped below $-18.9^{\circ}C$ 45 times in Cheongju and 32 times in Suwon during the same period, but it has not happened at all since 1991. It appears that the rising coefficient of the lowest temperature increases, as the latitude gets higher. As a result, L. indica and P. angustifolia which were planted in the central region of Korea, are considered in danger from freezing injury because the temperature can get very low intermittently in winter. But, the risk of freezing has reduced gradually as the lowest temperature raises each year.

Correlation between Patterns of Mdm2 SNIP 309 and Histopathological Severity of Helicobacter pylori Associated Gastritis in Thailand

  • Tongtawee, Taweesak;Dechsukhum, Chavaboon;Talabnin, Krajang;Leeanansaksiri, Wilairat;Kaewpitoon, Soraya;Kaewpitoon, Natthawut;Loyd, Ryan A;Matrakool, Likit;Panpimanmas, Sukij
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.17
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    • pp.7781-7784
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    • 2015
  • Background: The commonly held view of the tumor suppressor p53 is as a regulator of cell proliferation, apoptosis and many other biological processes as well as external and internal stress responses. Mdm2 SNIP309 is a negative regulator of p 53. Therefore, this study aimed to determine the correlation between the patterns of Mdm2 SNIP 309 and the inflammation grading of Helicobacter pylori associated gastritis in a Thai population. Materials and Methods: A cross-sectional study was carried out from November 2014 through June 2015. Biopsy specimens were obtained from infected patients and infection was proved by positive histology. The gastric mucosa specimens were sent to the Molecular Genetic Unit, Institute of Medicine, Suranaree University of Technology where they were tested by molecular methods to detect the patterns of Mdm2 SNIP 309 using the real-time PCR hybridization probe method. The results were analyzed and compared with the Updated Sydney classification. Results: A total of 100 infected patients were interviewed and gastric mucosa specimens were collected. In this study the percentage of Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygous was 78% and 19 % respectively whereas Mdm2 SNIP309 G/G homozygous was 3%. Mdm2 SNIP 309 T/T homozygous and Mdm2 SNIP309 G/T heterozygous correlated with mild to moderate inflammation (P<0.01) whereas Mdm2 SNIP309 G/G homozygous correlated with severe inflammation (P<0.01). Conclusions: Our study found the frequency of Mdm2 SNP309 G/G in our Thai population to be very low, and suggests that this can explain to some extent the low incidence of severe inflammation and gastric cancer changes in the Thai population. Mild to moderate inflammation are the most common pathologic gradings due to the unique genetic polymorphism of Mdm2 SNIP 309 in the Thai population.

Magnetoresistance of Bi Nanowires Grown by On-Film Formation of Nanowires for In-situ Self-assembled Interconnection

  • Ham, Jin-Hee;Kang, Joo-Hoon;Noh, Jin-Seo;Lee, Woo-Young
    • Proceedings of the Korean Magnestics Society Conference
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    • 2010.06a
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    • pp.79-79
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    • 2010
  • Semimetallic bismuth (Bi) has been extensively investigated over the last decade since it exhibits very intriguing transport properties due to their highly anisotropic Fermi surface, low carrier concentration, long carrier mean free path l, and small effective carrier mass $m^*$. In particular, the great interest in Bi nanowires lies in the development of nanowire fabrication methods and the opportunity for exploring novel low-dimensional phenomena as well as practical application such as thermoelectricity[1]. In this work, we introduce a self-assembled interconnection of nanostructures produced by an on-film formation of nanowires (OFF-ON) method in order to form a highly ohmic Bi nanobridge. A Bi thin film was first deposited on a thermally oxidized Si (100) substrate at a rate of $40\;{\AA}/s$ by radio frequency (RF) sputtering at 300 K. The sputter system was kept in an ultra high vacuum (UHV) of $10^{-6}$ Torr before deposition, and sputtering was performed under an Ar gas pressure of 2m Torr for 180s. For the lateral growth of Bi nanowires, we sputtered a thin Cr (or $SiO_2$) layer on top of the Bi film. The Bi thin films were subsequently put into a custom-made vacuum furnace for thermal annealing to grow Bi nanowires by the OFF-ON method. After thermal annealing, the Bi nanowires cannot be pushed out from the topside of the Bi films due to the Cr (or $SiO_2$) layer. Instead, Bi nanowires grow laterally as a mean s of releasing the compressive stress. We fabricated a self-assembled Bi nanobridge (d=192 nm) device in-situ using OFF-ON through annealing at $250^{\circ}C$ for 10hours. From I-V measurements taken on the Bi nanobridge device, contacts to the nanobridge were found highly ohmic. The quality of the Bi nanobridge was also proved by the high MR of 123% obtained from transverse MR measurements. These results manifest the possibility of self-assembled nanowire interconnection between various nanostructures for a variety of applications and provide a simple device fabrication method to investigate transport properties on nanowires without complex patterning and etching processes.

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The Effect of Science Teaching Efficacy Belief of Secondary School Teachers on Astronomy Topics: Based on Grounded Theories (중등 교사의 과학 교수 효능감이 천문 수업에 미치는 영향 : 근거이론을 중심으로)

  • Bae, Sunghee;Kim, Hyoungbum
    • The Journal of the Korea Contents Association
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    • v.16 no.3
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    • pp.607-616
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    • 2016
  • The purpose of this study was to confirm how the students have responded to their class according to STEB (science teaching efficacy belief) of secondary science teacher in astronomy classes. Middle school teachers in charge of 'The Solar System' and 'The Exosphere and Space Development' in the 2009 Revision Science Curriculum content system is selected as an object of study through random sampling method. Twenty-nine teachers were taken STEB questionnaire and asked to make it out. Twenty-seven completed a questionnaire of them is selected for this study. In addition, the top and bottom 5% selected through frequency analysis with the total score from the questionnaire were regarded as high and low STEB teachers. For data collection, this study was used methods such as semi-structured interviews, recording, participant observation. The results were as follows: First, science teachers of high STEB had a high accessibility about excellent professional knowledge and content of the curriculum relating to astronomical field. Second, high STEB teachers were prepared by the appropriate teaching strategies adequate to student-centered learning, whereas the low STEB teachers totally have had teacher-centered learning. Third, high STEB teachers had been provided as the idea that you can take advantage of a variety of instruments, as well as scientific knowledge through the Astronomical Society. Therefore, confidence in astronomical class and teaching strategies through content of the curriculum were very important variables to predict the STEB as well as astronomy-related class activities such as astronomical observations.

[ $8{\sim}10.9$ ]-GHz-Band New LC Oscillator with Low Phase-Noise and Wide Tuning Range for SONET communication (SONET 통신 시스템을 위한 $8{\sim}10.9$ GHz 저 위상 잡음과 넓은 튜닝 범위를 갖는 새로운 구조의 LC VCO 설계)

  • Kim, Seung-Hoon;Cho, Hyo-Moon;Cho, Sang-Bock
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.1
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    • pp.50-55
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    • 2008
  • In this paper, New LC VCO with $8{\sim}10.9$ GHz Band has been designed using commercial $0.35-{\mu}m$ CMOS technology. This proposed circuit is consisted of the parallel construction of the typical NMOS and PMOS cross-coupled pair which is based on the LC tank, MOS cross-coupled pair which has same tail current of complementary NMOS and PMOS, and output buffer. The designed LC VCO, which is according to proposed structure in this paper, takes a 29% improvement of the wide tuning range as 8 GHz to 10.9 GHz, and a 6.48mW of low power dissipation. Its core size is $270{\mu}m{\times}340{\mu}m$ and its phase noise is as -117dBc Hz and -137dBc Hz at 1-MHz and 10-MHz offset, respectively. FOM of the new proposed LC VCO gets -189dBc/Hz at a 1-MHz offset from a 10GHz center frequency. This design is very useful for the 10Gb/s clock generator and data recovery integrated circuit(IC) and SONET communication applications.

A study on the Characteristics of the Adult Men Sound as by Sasang Constitution Analysed with PSSC-2004 (사상체질음성분석기(四象體質音聲分析機)(PSSC-2004)를 통한 성인남성(成人男性)의 체질별(體質別) 음향특성(音響特性))

  • Kim, Dong-Jun;Jung, Woon-Ki;Choi, Jae-Wan;Kim, Dal-Rae;Jeon, Jong-Weon
    • Journal of Sasang Constitutional Medicine
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    • v.17 no.1
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    • pp.67-83
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    • 2005
  • 1. Objectives The purpose of this study lies on the objectification of the Sasang Constitutional diagnosis. This study was analyzing the constitutional characteristic of adult men voices by PSSC-2004. 2. Methods The study was conducted on the subjects inputted /a/ 2.5-3 sec of 231 adult men voices to PSSC-2004. The statistical analyses are applied to three groups: total group, under 55 year-old group, over 55 year-old group. The group of total 231 was composed with 5 Taeyangins, 32 Soyangins, 102 Taeumins and 92 Soeumins. The under 55 years old group was composed with 4 Taeyangins, 23 Soyangins, 83 Taeumins and 77 Soeumins. The over 55 year-old group was composed with 1 Taeyangin, 9 Soyangins, 19 Taeumins and 15 Soeumins. 3. Results 1) In total group, the Soeumin's mean value of center pitch(4)$(1,000{\sim}2,000Hz)$ was significantly high compared with the others (P=0.034). 2) In total group, the Soeumin's group 3 APQ was significantly low compared with the others (P=0.042). 3) In under 55 year-old group, the Soeumin's center value of center pitch 4$(1,000{\sim}2,000Hz)$ was significantly high compared with the others (P=0.025) 4) In over 55 year-old group, no statistical significance was found between the Taeyangin, Soyangin, Taeumin and Soeumin. 4. Conclusions In under 55 year-old group, Soeumin's voice showed high pitched sound (clearness) at the low frequency (1000-2000Hz). In over 55 year-old group, there is no significant differences. This fits in with that 'Soeumin's voice is 'Yu-tone' born by 'Shang-tone', very short and high.' 'Yu-tone' corresponds to 'Ra' and witch is highest among Gong, Shang, Gao, Chi and Yu. This is related with the appearance that the Soeumin's voice is weak, thin and high tone. Therefore it is supposed that Soeumin adult men's voices are thick, and there are vibrations of the ending. It is accepted one of the Soeumin's characters like as a mild tremor of limbs and deep breath caused by Soeumin's Qi-deficiency. This outcome accords with the theory that Soeumin's Qi is less than the Other constitutions.

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