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Effectiveness of Transcranial Direct Current Stimulation(tDCS) on Upper Extremity Function in Stroke Patients : A Systematic Review and Meta-Analysis (뇌졸중 환자의 상지기능에 대한 경두개 직류자극술 효과 : 체계적 고찰 및 메타분석)

  • Won, Kyung-A;Yang, Min Ah;Park, Hae Yean;Park, Ji-Hyuk
    • Therapeutic Science for Rehabilitation
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    • v.9 no.1
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    • pp.7-23
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    • 2020
  • Objective : The purpose of this article was to analyze the effects of tDCS on the recovery of upper limb function in stroke patients. Methods : We searched for papers published in journals between 2009 to 2018, using NDSL and RISS. A total 14 experimental research papers were selected for analysis. The quality of the 14 articles was evaluated using the PEDro scale and 12 articles were analyzed through the Comprehensive Meta Analysis 3.0 program. Results : All of the 14 articles that were systematically reviewed in this study were published in foreign journals. The effect sizes for upper extremity(U/Ex) strength and U/Ex motion were 0.19(small size effect) and 0.49(medium size effect) respectively. Furthermore, the effect sizes of anode mode and cathode mode were 0.71(large size effect) and 0.41(medium size effect), respectively. The effect size of U/Ex motion and the anode mode were statistically significant(p<0.05). Conclusion : We identified that tDCS can be a useful rehabilitation technique for stroke patients with limited upper body function. These findings are expected to help with suggestions for basic data on new rehabilitation techniques for stroke patients and the planning of effective interventions.

Reconstructed Adeno-Associated Virus with the Extracellular Domain of Murine PD-1 Induces Antitumor Immunity

  • Elhag, Osama A.O.;Hu, Xiao-Jing;Wen-Ying, Zhang;Li, Xiong;Yuan, Yong-Ze;Deng, Ling-Feng;Liu, De-Li;Liu, Ying-Le;Hui, Geng
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.4031-4036
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    • 2012
  • Background: The negative signaling provided by interactions of the co-inhibitory molecule, programmed death-1 (PD-1), and its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), is a critical mechanism contributing to tumor evasion; blockade of this pathway has been proven to enhance cytotoxic activity and mediate antitumor therapy. Here we evaluated the anti-tumor efficacy of AAV-mediated delivery of the extracellular domain of murine PD-1 (sPD-1) to a tumor site. Material and Methods: An rAAV vector was constructed in which the expression of sPD-1, a known negative regulator of TCR signals, is driven by human cytomegalovirus immediate early promoter (CMV-P), using a triple plasmid transfection system. Tumor-bearing mice were then treated with the AAV/sPD1 construct and expression of sPD-1 in tumor tissues was determined by semi quantitative RT-PCR, and tumor weights and cytotoxic activity of splenocytes were measured. Results: Analysis of tumor homogenates revealed sPD-1 mRNA to be significantly overexpressed in rAAV/sPD-1 treated mice as compared with control levels. Its use for local gene therapy at the inoculation site of H22 hepatoma cells could inhibit tumor growth, also enhancing lysis of tumor cells by lymphocytes stimulated specifically with an antigen. In addition, PD-1 was also found expressed on the surfaces of activated CD8+ T cells. Conclusion: This study confirmed that expression of the soluble extracellular domain of PD-1 molecule could reduce tumor microenvironment inhibitory effects on T cells and enhance cytotoxicity. This suggests that it might be a potential target for development of therapies to augment T-cell responses in patients with malignancies.

Implementation of Analog Signal Processing ASIC for Vibratory Angular Velocity Detection Sensor (진동형 각속도 검출 센서를 위한 애널로그 신호처리 ASIC의 구현)

  • 김청월;이병렬;이상우;최준혁
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.40 no.4
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    • pp.65-73
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    • 2003
  • This paper presents the implementation of an analog signal-processing ASIS to detect an angular velocity signal from a vibrator angular velocity detection sensor. The output of the sensor to be charge appeared as the variation of the capacitance value in the structure of the sensor was detected using charge amplifiers and a self oscillation circuit for driving the sensor was implemented with a sinusoidal self oscillation circuit using the resonance characteristics of the sensor. Specially an automatic gain control circuit was utilized to prevent the deterioration of self-oscillation characteristics due to the external elements such as the characteristic variation of the sensor process and the temperature variation. The angular velocity signal, amplitude-mod)Hated in the operation characteristics of the sensor, was demodulated using a synchronous detection circuit. A switching multiplication circuit was used in the synchronous detection circuit to prevent the magnitude variation of detected signal caused by the amplitude variation of the carrier signal. The ASIC was designed and implemented using 0.5${\mu}{\textrm}{m}$ CMOS process. The chip size was 1.2mm x 1mm. In the experiment under the supply voltage of 3V, the ASIC consumed the supply current of 3.6mA and noise spectrum density from dc to 50Hz was in the range of -95 dBrms/√Hz and -100 dBrms/√Hz when the ASIC, coupled with the sensor, was in normal operation.

Digital watermarking algorithm for authentication and detection of manipulated positions in MPEG-2 bit-stream (MPEG-2비트열에서의 인증 및 조작위치 검출을 위한 디지털 워터마킹 기법)

  • 박재연;임재혁;원치선
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.5
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    • pp.378-387
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    • 2003
  • Digital watermarking is the technique that embeds invisible signalsincluding owner identification information, specific code, or pattern into multimedia data such as image, video and audio. Watermarking techniques can be classified into two groups; robust watermarking and fragile(semi-fragile) watermarking. The main purpose of the robust watermarking is the protection of copyright, whereas fragile(semi-fragile) watermarking prevents image or video data from illegal modifications. To achieve this goal watermark should survive from unintentional modifications such as random noise or compression, but it should be fragile for malicious manipulations. In this paper, an invertible semi-fragile watermarkingalgorithm for authentication and detection of manipulated location in MPEG-2 bit-stream is proposed. The proposed algorithm embeds two kinds of watermarks, which are embedded into quantized DCT coefficients. So it can be applied directly to the compressed bit-stream. The first watermark is used for authentication of video data. The second one is used for detection of malicious manipulations. It can distinguish transcodingin bit-stream domain from malicious manipulation and detect the block-wise locations of manipulations in video data. Also, since the proposed algorithm has an invertible property, recovering original video data is possible if the watermarked video is authentic.

High-performance 94 GHz Single Balanced Mixer Based On 70 nm MHEMT And DAML Technology (70 nm MHEMT와 DAML 기술을 이용한 우수한 성능의 94 GHz 단일 평형 혼합기)

  • Kim Sung-Chan;An Dan;Lim Byeong-Ok;Beak Tae-Jong;Shin Dong-Hoon;Rhee Jin-Koo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.4 s.346
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    • pp.8-15
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    • 2006
  • In this paper, the 94 GHz, low conversion loss, and high isolation single balanced mixer is designed and fabricated using GaAs-based metamorphic high electron mobility transistors (MHEMTs) with 70 nm gate length and the hybrid ring coupler with the micromachined transmission lines, dielectric-supported air-gapped microstrip lines (DAMLs). The 70 nm MHEMT devices exhibit DC characteristics with a drain current density of 607 mA/mm an extrinsic transconductance of 1015 mS/mm. The current gain cutoff frequency ($f_T$) and maximum oscillation frequency ($f_{max}$) are 320 GHz and 430 GHz, respectively. The fabricated hybrid ring coupler shows wideband characteristics of the coupling loss of $3.57{\pm}0.22dB$ and the transmission loss of $3.80{\pm}0.08dB$ in the measured frequency range of 85 GHz to 105 GHz. This mixer shows that the conversion loss and isolation characteristics are $2.5dB{\sim}>2.8dB$ and under -30 dB, respectively, in the range of $93.65GHz{\sim}94.25GHz$. At the center frequency of 94 GHz, this mixer shows the minimum conversion loss of 2.5 dB at a LO power of 6 dBm To our knowledge, these results are the best performances demonstrated from 94 GHz single balanced mixer utilizing GaAs-based HEMTs in terms of conversion loss as well as isolation characteristics.

Size-sorting of Micron-sized Particles using Two Gravitational SPLITT Fractionation (GSF) Connected in a Series (Tandem GSF)

  • Kwon, Min-Hyuk;Moon, Yoon-Jung;Jung, Euo-Chang;Lee, Kyou-Ho;Lee, Seung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.32 no.2
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    • pp.681-686
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    • 2011
  • SPLITT Fractionation (SF) provides separation of sample into two subpopulations. Separation into more than two subpopulations requires repeated SF operations. In this study, two Gravitation SF (GSF) channels were connected in a series (Tandem GSF) to obtain a separation into three subpopulations and to improve the fractionation efficiency (FE) of the fraction-b in the full-feed depletion (FFD) mode. In a single channel FFD-GSF operation, the fraction-a contained mostly the beads smaller than the cutoff diameter ($d_c$), while the fraction-b contained beads smaller than $d_c$ as well as those larger than dc, as expected. The measured FE's of the fraction-b are much lower than those of the fraction-a in all cases. The FE's of the fraction-a are higher than 84% with the average of about 91%, while those of the fraction-b are lower than 60% with the average of about 43%. No particular trends were found between FE and $d_c$, indicating the performance of FFD-GSF does not change with $d_c$ in the range where tested. Also no clear trends were observed between the FE and the sample-feeding flow rate, indicating higher sample-feeding rate can be used to increase the sample throughput without losing resolution. When two GSF channels were connected so that the flow stream emerging from the outlet-b of the channel-1 is fed directly into the channel-2, all three FE's measured for the fraction-1a were high with the average value of 99%, indicating it contains almost purely the beads smaller than $d_c$. The FE's measured for the fraction-2a are still good with the average value of 92%. The FE's measured for the fraction-2b are 64% in average, which is about 20% improvement from those obtained in a single channel FFD-GSF at the same conditions.

A Study on the filtering bed of porous sintering-product and hydrophytes for sewage treatment (오·폐수처리를 위한 수생식물 다공성 소결체여상의 기초연구)

  • Kim, Ju-Hyung;Yun, Chan;Oh, Joon-Seong
    • Clean Technology
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    • v.7 no.2
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    • pp.89-97
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    • 2001
  • The purpose of this study was to find the optimum condition of the high removal efficiency of water pollutant as sewage treatment technology using a filtering bed charged with porous sintering-pellet which was planted with hydrophytes. Experiment was carried out by changing concentration of water pollutants(COD, T-N, T-P), kind of hydrophyte, kinds of filtering material and size, and HRT. The result of removal efficiency was obtained as following: COD removal 73.8~87.1% for input concentration range of 50~450mg/L, T-N removal 61.3~77.3% for input concentration range of 7~124mg/L, T-P removal 89.5~99.1% for input concentration ranger of 3~27mg/L. In a comparative experiment of three kinds of hydrophyte(Iris pseudoacorus, Phragmites communis $T_{RIN}$., Oenanthe javanica Dc.), the best removal efficiency of COD and T-N was gained with Iris pse-udoacorus, and Phragmites communis $T_{RIN}$ showed better result than two hydrophytes for the removal efficiency of T-P. In a comparative experiment of four kinds of filtering-materials, the removal efficiencies were in the order of porous sintering-pellet, gravel, nonused-tire and nonused-concrete. It was found that for the porous sintering-pellet, the smaller its diameter, the better its result. In the filtering bed in which was charged with porous sintering-pellets of 5mm diameter and planted with Iris pseudoacorus, the removal efficiency of COD, T-N and T-P were over 80%, 70% and 90% under the concentration of COD 250mg/L, T-N 70mg/L and T-P 15mg/L for 24hrs treatment. Thus, we concluded that a filtering bed charged with porous sintering-pellet and planted with hydrophytes will be suitable for treatment of sewage water as a pro-natural treatment technology.

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A molecular systematic study of Korean Iris (Iridaceae) based on RAPD analysis (RAPD에 의한 한국산 붓꽃속(Iris)의 계통분류학적 연구)

  • Park, Seon-Joo;Sim, Jeong-Ki;Park, Hong-Duok
    • Korean Journal of Plant Taxonomy
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    • v.32 no.4
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    • pp.383-396
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    • 2002
  • RAPD analyses were compared for 17 taxa of Korean Iris including the subgenus Sisyrinchium and Belamcanda. Eighty scorable RAPD markers were formed from the PCR reactions using 10 random oligoprimers. In this systematic analyses which used neighbor-joining methods including bootstrapping analyses with genetic coefficients, the Korean Iris were divided into three subgenera (Limniris, Crossiris, Pardanthopsis), or two genera (Limniris, Pardanthopsis). The molecular data agree with the previous classification system that recognized two sections and six series for the subgenus Limniris because the subgenus is comprised of four clades in the RAPD analyses. According to the molecula data, the series Chinensis should be divided into two groups. The minutoaurea group is composed of I. koreana, I. odaesanensis, and I. minitoaurea, while the rossi group is comprised of two varieties of I. rossi. The series Tripetalae is closely allied with the series Sibiricae, whereas the series Ensatae is recognized as a sister group to the series Ruthencae. The molecular phylogeny, which was based on RAPD analysis, for the most part agreed with the data proposed by previous authors. This is because the basis of morphological and ITS sequence data suggests that the RAPD markers should be very useful in addressing phylogenetic questions about the genus Iris.

4-D Inversion of Geophysical Data Acquired over Dynamically Changing Subsurface Model (시간에 대해 변화하는 지하구조에서 획득한 물리탐사 자료의 역산)

  • Kim, Jung-Ho;Yi, Myeong-Jong
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.117-122
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    • 2006
  • In the geophysical monitoring to understand the change of subsurface material properties with time, the time-invariant static subsurface model is commonly adopted to reconstruct a time-lapse image. This assumption of static model, however, can be invalid particularly when fluid migrates very quickly in highly permeable medium in the brine injection experiment. In such case, the resultant subsurface images may be severely distorted. In order to alleviate this problem, we develop a new least-squares inversion algorithm under the assumption that the subsurface model will change continuously in time. Instead of sampling a time-space model into numerous space models with a regular time interval, a few reference models in space domain at different times pre-selected are used to describe the subsurface structure continuously changing in time; the material property at a certain space coordinate are assumed to change linearly in time. Consequently, finding a space-time model can be simplified into obtaining several reference space models. In order to stabilize iterative inversion and to calculate meaningful subsurface images varying with time, the regularization along time axis is introduced assuming that the subsurface model will not change significantly during the data acquisition. The performance of the proposed algorithm is demonstrated by the numerical experiments using the synthetic data of crosshole dc resistivity tomography.

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An efficient 2.5D inversion of loop-loop electromagnetic data (루프-루프 전자탐사자료의 효과적인 2.5차원 역산)

  • Song, Yoon-Ho;Kim, Jung-Ho
    • Geophysics and Geophysical Exploration
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    • v.11 no.1
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    • pp.68-77
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    • 2008
  • We have developed an inversion algorithm for loop-loop electromagnetic (EM) data, based on the localised non-linear or extended Born approximation to the solution of the 2.5D integral equation describing an EM scattering problem. Source and receiver configuration may be horizontal co-planar (HCP) or vertical co-planar (VCP). Both multi-frequency and multi-separation data can be incorporated. Our inversion code runs on a PC platform without heavy computational load. For the sake of stable and high-resolution performance of the inversion, we implemented an algorithm determining an optimum spatially varying Lagrangian multiplier as a function of sensitivity distribution, through parameter resolution matrix and Backus-Gilbert spread function analysis. Considering that the different source-receiver orientation characteristics cause inconsistent sensitivities to the resistivity structure in simultaneous inversion of HCP and VCP data, which affects the stability and resolution of the inversion result, we adapted a weighting scheme based on the variances of misfits between the measured and calculated datasets. The accuracy of the modelling code that we have developed has been proven over the frequency, conductivity, and geometric ranges typically used in a loop-loop EM system through comparison with 2.5D finite-element modelling results. We first applied the inversion to synthetic data, from a model with resistive as well as conductive inhomogeneities embedded in a homogeneous half-space, to validate its performance. Applying the inversion to field data and comparing the result with that of dc resistivity data, we conclude that the newly developed algorithm provides a reasonable image of the subsurface.