• Title/Summary/Keyword: left-handed

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The Performance Comparison of The Harmonic Generators using Nonlinear Transmission Lines (비선형 전송선로를 이용한 고조파 발생기 성능 비교)

  • Park, Soonwoo;Kim, Hongjoon;Yoo, Hyoungsuk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.8
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    • pp.1212-1216
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    • 2015
  • In this paper, we compared the performance of the Right Handed Nonlinear Transmission Line (RH-NLTL) and Left Handed Nonlinear Transmission Line (LH-NLTL) as a harmonic generator. For a performance comparison, we fabricated both a RH-NLTL and a LH-NLTL harmonic generator whose operational bandwidth is from 0.5 GHz to 1.5 GHz. Under the each condition for the RH-NLTL and the LH-NLTL to maximize second harmonic, the output power of the second harmonic was 9.33 dB lower than the input power for the RH-NLTL and 12.67 dB lower than the input power for the LH-NLTL. Under the each condition for the RH-NLTL and the LH-NLTL to maximize third harmonic, the output power of the third harmonic was 13.33 dB lower than the input power for the RH-NLTL and 14.83dB lower than the input power for the LH-NLTL. Also, we have observed that, generatlly, a RH-NLTL is useful in generating various multiple harmonics and a LH-NLTL is useful in generating a specific order of harmonic by adjusting a proper DC vias, input frequency and input power. These tendencies could be a good guideline to use NLTLs as a frequency multiplier.

The Formation of Rope- and Pebbles-Type Aggregation from the Micro-End-to-End and -Side-by-Side Aggregates in Poly(L-proline) Solutions

  • 김현돈
    • Bulletin of the Korean Chemical Society
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    • v.18 no.9
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    • pp.929-933
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    • 1997
  • Morphological studies in the micro-end-to-end (m-E-E) and micro-side-by-side (m-S-S) aggregations were conducted by using of scanning electron microscope (SEM) for the samples precipitated by heating of the end-products of the transition of FormⅡ (left-handed helix, three peptides per turn, 31) Form Ⅰ (right-handed helix, 3.3 peptides per turn, 103) in poly(L-proline) (PLP) in acetic acid(water)-propanol (1:9 v/v) solvent. The observed morphology for the solide state shows a rope (or super helical) type and pebbles type aggregate for the (m-E-E) and (m-S-S) aggregate respectively. The viscosities were also measured during the heat-precipitation in order to elucidate the process of formation of the rope- and pebbles-type aggregates. The result for the (m-E-E) aggregations exhibit two steps, i.e., at first, the viscosity increases with time (step 1), thereafter it decrease until attain the last value (step 2). But the (m-S-S) aggregations show only one step in the decreases in viscosity. On the bases of all experimental results it is possible to propose a reasonable mechanism for the formation of the two types of aggregates of the (m-E-E) and (m-S-S).

Z-DNA-Containing Long Terminal Repeats of Human Endogenous Retrovirus Families Provide Alternative Promoters for Human Functional Genes

  • Lee, Du Hyeong;Bae, Woo Hyeon;Ha, Hongseok;Park, Eun Gyung;Lee, Yun Ju;Kim, Woo Ryung;Kim, Heui-Soo
    • Molecules and Cells
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    • v.45 no.8
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    • pp.522-530
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    • 2022
  • Transposable elements (TEs) account for approximately 45% of the human genome. TEs have proliferated randomly and integrated into functional genes during hominoid radiation. They appear as right-handed B-DNA double helices and slightly elongated left-handed Z-DNAs. Human endogenous retrovirus (HERV) families are widely distributed in human chromosomes at a ratio of 8%. They contain a 5'-long terminal repeat (LTR)-gag-pol-env-3'-LTR structure. LTRs contain the U3 enhancer and promoter region, transcribed R region, and U5 region. LTRs can influence host gene expression by acting as regulatory elements. In this review, we describe the alternative promoters derived from LTR elements that overlap Z-DNA by comparing Z-hunt and DeepZ data for human functional genes. We also present evidence showing the regulatory activity of LTR elements containing Z-DNA in GSDML. Taken together, the regulatory activity of LTR elements with Z-DNA allows us to understand gene function in relation to various human diseases.

The Change of Mu Rhythm according to Familiarity of Observation Stimulus in Stroke Patients (관찰 자극의 친숙도에 따른 뇌졸중 환자의 뮤리듬 변화)

  • Yun, Tae-Won;Lee, Moon-Kyu
    • PNF and Movement
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    • v.9 no.4
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    • pp.33-40
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    • 2011
  • Purpose : The aims of this study was to identify changes mu rhythm according to familiarity with a stimulus in people with stroke. Methods : Seventeen right-handed participants were asked to observe 2 different stimulus; a non-familiarity stimulus condition (NFSC), and a familiarity stimulus condition (FSC). Electroencephalogram (EEG) signals from electrodes on the participant's scalp were recorded during action observation. The activation of the mirror neuron system was compaired between FSC and NFSC by a paired t-test. An independent t-test was used to compare the difference between right and left hemispheres for the activation of the mirror neuron system during action observation of performing a task with the right hand. Results : The result of paired t-test showed no significantly difference between NFSC and FSC in the activation of the mirror neuron system. The Result of independent t-test also showed no significantly difference in the activation of mirror neuron system between the right and left hemispheres. Conclusion : The familiarity with a stimulus had no signigicant effect on the activation of the mirror neuron system according to the familiarity and in either the right or left hemispheres in people with chronic stroke.

Acupuncture for Attenuating Frontal Lobe α Band Asymmetry Induced by Anger: a pilot study

  • Sung-A Kim;Yujin Choi;Seung-Hun Cho
    • Journal of Pharmacopuncture
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    • v.26 no.3
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    • pp.276-284
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    • 2023
  • Objectives: Previous studies have shown that anger can lead to frontal lobe α (8-13 Hz) band asymmetry (FAA) in electroencephalogram (EEG), in accordance with motivational direction. This pilot study aimed to investigate the impact of acupuncture on FAA elicited by anger. Methods: Thirty-four right-handed participants scoring above 75 points on the Novaco Anger Scale were included. Baseline EEG signals were recorded for eight minutes using a 32-channel cap under comfortable conditions. Anger was induced through a nine-minute sequence of Articulated Thoughts in Simulated Situations (ATSS) task. Following that, participants received acupuncture at GB20 and GB21 for 10 minutes. Fast Fourier transform was employed for frequency analysis, and repeated measure ANOVA was conducted for statistical analysis. Results: The results revealed that participants exhibited significantly higher FAA (p = 0.026), particularly in the left hemisphere, after the ATSS task sequence compared to the baseline. During acupuncture treatment, the greater left-sided FAA was significantly reduced (p = 0.027) and reversed. Upon the cessation of acupuncture, FAA returned to a value between the baseline and the anger-evoked stage (p = 0.046). Conclusion: The EEG results of this study revealed that anger stimulation induced an increase in left-sided FAA, which was effectively alleviated by acupuncture. This led to an immediate restoration of FAA asymmetry induced by anger. These findings suggest the potential of acupuncture as a treatment option for reducing FAA associated with anger.

Analysis of Sports Biomechanical Variable on the Motions of Left and Right Spikes of Volleyball (배구 레프트 스파이크와 라이트 스파이크 동작에 대한 운동역학적 변인 비교 분석)

  • Cho, Ju-Hang;Ju, Myung-Duck
    • Korean Journal of Applied Biomechanics
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    • v.16 no.4
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    • pp.125-134
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    • 2006
  • The purpose of this study was to analyze the Biomechanical elements by looking at the differences on the motions of the right and left spikes of right-handed offense volleyball players, using 3D image analysis and force platform. For that purpose, spike motions of six male university volleyball players were recorded three times each using two 16mm high speed cameras and the speed of recording was set at 60 frames/sec. The coordinated raw data was leveled as 6Hz using low pass filtering method and the calculation of 3D coordinates was done by using a DLT (Direct Linear Transformation) method. Also KWON 3D program was used to analyze the variables. Through the experiments and research, the following results were found: That is, in case of the right spike, the required time from the toss to the impact, which affected the success rate of offense showed as longer and on the take-off, the exact timing to touch the ball was longer because the pace between right and left feet was wider, and also after the jump, the distance between the feet indicated shorter, than the left. In addition, the degree of somersault and horizontal adduction of shoulder joint was smaller and the degree of medial rotation of shoulder joint showed bigger than the left, so it indicated that it was not centered on the body, but by the arm with an axis of shoulder using a swing motion. After the impact, the speed of the ball indicated slower compared to the left spike.

Low Phase Noise VCO Using Novel Harmonic Control Circuit Based on Composite Right/Left-Handed Transmission Line (혼합 우좌향 전송 선로 기반의 새로운 고조파 조절 회로를 이용한 저위상 잡음 전압 제어 발진기)

  • Choi, Jae-Won;Seo, Chul-Hun
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.1
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    • pp.84-90
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    • 2010
  • In this paper, a novel voltage-controlled oscillator (VCO) using the harmonic control circuit based on the composite right/left-handed (CRLH) transmission lines (TLs) is presented to reduce the phase noise without the reduction of the frequency tuning range and miniaturize the circuit size. The phase noise is reduced by the novel harmonic control circuit having the short impedances for the second- and third-harmonic components. The proposed harmonic control circuit is designed by using the CRLH TLs with the dual-band characteristic by the frequency offset and phase slope of the CRLH TLs. The high-Q resonator has been used to reduce the phase noise, but has the problem of the frequency tuning range reduction. However, the frequency tuning range of the proposed VCO has not been reduced because the phase noise has been reduced without the high-Q resonator. The miniaturization of the circuit size is achieved by using the CRLH TLs instead of the conventional right-handed (RH) TLs. The phase noise of VCO is -119.17 ~ -117.50 dBc/Hz at 100 kHz in the tuning range of 5.731 ~ 5.938 GHz.

Functional MRI of Language Area (언어영역의 기능적 자기공명영상)

  • 유재욱;나동규;변홍식;노덕우;조재민;문찬홍;나덕렬;장기현
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.1
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    • pp.53-59
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    • 1999
  • Purpose : To evaluate the usefulness of functional MR imaging (fMRI) for language mapping and determination of language lateralization. Materials and Methods : Functional maps of the language area were obtained during word generation tasks and decision task in ten volunteers (7 right handed, 3 left-handed). MR examinations were performed at 1.5T scanner with EPI BOLD technique. Each task consisted of three resting periods and two activation periods with each period of 30 seconds. Total acquisition time was 162 sec. SPM program was used for the postprocessing of images. Statistical comparisons were performed by using t-statistics on a pixel-by- pixel basis after global normalization by ANCOVA. Activation areas were topographically analyzed (p>0.001) and activated pixels in each hemisphere were compared quantitatively by lateralization index. Results : Significant activation signals were demonstrated in 9 of 10 volunteers. Activation signals were found in the premotor and motor cortices, the inferior frontal, inferior parietal, and mid-temporal lobes during stimulation tasks. In the right handed seven volunteers, activation of language areas was lateralized to the left side. Verb generation task produced stronger activation in the language areas and higher value of lateralization index than noun generation task or decision task. Conclusion : fMRI could be a useful non-invasive method for language mapping and determination of language dominance.

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Effects of Culture Temperatures and Media on Morphological Changes of Leptospira interrogans Isolated in Korea (한국에서 분리된 Leptospira의 배양조건에 따른 형태변화)

  • Lee, Tae-Yoon;Park, Jeon-Han;Uhm, Jeong-Ran;Lee, Bong-Ki;Lee, Won-Young;Kim, Joo-Deuk;Youn, Jung-Koo;Hahn, Kyu-Woung
    • The Journal of the Korean Society for Microbiology
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    • v.22 no.3
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    • pp.209-218
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    • 1987
  • Leptospira interrogans, the causative organism of leptospirosis, is characterized by a fine helical morphology, and the helix is almost always right-handed. However, one of the striking features of recent isolates of L. interrogans in Korea was the heterogeneity in their morphology. Even under optimal culture conditions($30^{\circ}C$, EMJH medium), rods, spiral forms with right or left-handed helices, and even spherical forms of L. interrogans were present. Although the literature notes the presence of left-handed helices, long rods, and spherical forms in cultures of L. interrogans isolates, little is known about the cause of this morphologic heterogeneity. In an attempt to answer this question, this study was initiated to examine the effects of culture conditions, especially temperature and medium, on the morphology of L. interrogans. Four temperatures($5^{\circ}C$, $15^{\circ}C$, $30^{\circ}C$, and $37^{\circ}C$) and two types of media(Fletcher and EMJH) were used; one strain from Korean isolates and L. interrogans serovar canicola obtained from the Pasteur Institute(Paris, France) were employed throughout the study. The findings are as follows: 1. The L. interrogans isolated in Korea(UM-19) had a larger cell diameter($0.25{\sim}0.30\;{\mu}m$: $0.10{\sim}0.15\;{\mu}m$), and helix diameter($0.10{\sim}0.60\;{\mu}m$: $0.10{\sim}0.15\;{\mu}m$) than that obtained from the Pasteur Institute, but they varied in their distances between the helices($0.31{\sim}1.00\;{\mu}m$: $0.50{\sim}0.70\;{\mu}m$). 2, When UM-19 was grown at $37^{\circ}C$ after months or longer preincubation at $5^{\circ}C$ or $15^{\circ}C$, the majority of the organisms were spiral forms; however, they became rods when subcultured at $30^{\circ}C$ or $37^{\circ}C$. No significant morphological differences were found between Fletcher and EMJH media. 3. When L. interrogans serovar canicola was subcultured more than ten times at $37^{\circ}C$, some of the organism lost their motility as well as the hooks at either one or both ends, but only in Fletcher medium. The number of variants increased with the frequency of subculturing. These findings suggested that L. interrogans strain (UM-19) is different, in their morphology, from that of the Pasteur Institute, and its various morphologies may represent stages of the life cycle and vary with incubation temperature.

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A study of the Korean Inclination to visual equivocality (시각적 등가성에 대한 한국인의 성향 연구)

  • 오근재
    • Archives of design research
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    • v.15 no.4
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    • pp.359-368
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    • 2002
  • This study was conducted to analyze the Korean inclination to visual equivocality. Similar studies conducted by several psychologists were reviewed in order to determine whether we can put equal value on the visual equivocality which is often shown in natural appearance. This Korean inclination was also investigated with the help of a public survey. The following conclusions were derived from the study. - In reality, there is no visual equivocality for Koreans except in some specific cases. - It is true that, on a screen, a diagonal line from the lower right to the upper left produces a stronger feeling of upward tendency than one from the lower left to the upper right. - The idea that the right side of a screen looks heavier than the left one was not supported and should be rejected for Koreans. - It was discovered that the user interface is working when a person is describing a natural appearance or looking at a description. This fact is generally accepted for Koreans, the majority of whom are right-handed. - Until now, the idea of a Korean superiority toward the left side in visual expression has been found in our culture. In short, it was uncovered that Korean people generally do not have visual equivocality but, instead, have an inclination to left side rather than the right from various aspects.

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