• Title/Summary/Keyword: Modulation

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Development of Irreversible Micro-size Ferromagnetic Structures by Hydrogenation and Electron-beam Lithography (수소화 및 전자빔 사진식각 기술에 의한 비가역적 마이크로 크기의 강자성 구조체 개발)

  • Yun Eui-Jung
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.1 s.343
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    • pp.7-12
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    • 2006
  • In this study, we developed irreversible and stable micro-size ferromagnetic structures utilizing hydrogenation and electron-beam lithography processes. The compositionally modulated (CM) Fe-Zr thin films that had average compositions $Fe_XZr_{100-x}$ with $x=65-85\%$ modulation periods of similar to 1 nm, and total thicknesses of similar to 100 m were prepared. The magnetic properties of CM Fe-Zr thin films were measured using a SQUID magnetometer, VSM and B-H loop tracer. After hydrogenation, the CM films exhibited larger magnetic moment increases than similar homogeneous alloy films for all compositions and かey showed largest increase in $Fe_{80}Zr_{20}$ composition. After aging in air at $300^{\circ}K$ the hydrogenated $Fe_{80}Zr_{20}$ CM films showed much larger magnetic moment increases, indicating that they relax to a stable, irreversible, soft magnetic state. The selective hydrogenation through electron-beam lithographed windows were performed after the circle shaped windows were prepared on $Fe_{80}Zr_{20}$ CM films by electron beam lithography. The hydrogenation through electron-beam resist and W lithographic techniques give a $49\%$ magnetic moment increase. This method can be applied to nano scale structures.

Modulation of Bone Mass, Strength and Turnover by a Cervi Pantotrichum Cornu Herbal Acupuncture in adjuvant-Induced Arthritic Rats (Adjuvant로 유발된 관절염 실험용쥐에서 골체, 골강도 및 골대체율의 변화에 대한 녹용 약침의 효과)

  • Choi, Byeong-joon;Kim, Min-jeong;Park, Sang-dong;Lee, A-ram;Jang, Jun-hyouk;Kim, Kyung-ho
    • Journal of Acupuncture Research
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    • v.19 no.5
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    • pp.219-233
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    • 2002
  • 면역억제활성이 알려진 Cerves korean TEMMINCK var. manchur-icus Swinhoe(Nokyong) 약침(CPH)은 다모 뿔의 녹용을 열수추출한 용액이다. 본 연구에서는 녹용 약침의 효과를 adjuvant 유발 관절염 실험용쥐를 이용하여 골체, 골강도 및 골대체율의 감소를 평가하였다. 위의 골 대사 관련 검정실험을 위하여 6주령의 암컷 실험용쥐에 20일간 약물투여를 실시하였다. 실험적인 관절염유발은 실험용쥐의 뒤쪽 다리에 Adjuvant를 주사하여 유발시킨 결과, 요부의 골 무기질함량과 밀도(BMC, BMD) 그리고 압축강도는 관절염 실험용쥐에서 감소되었다. 10일 경과 후 골형성도(BFR/BS, BFR/BV)의 조직형태학적 기준척도인 혈청 osteocalcin 수가 정상대조군과 비교해 볼 때 현저하게 감소되었다. 그러나, 몸무게로 나눈 BMC치는 관절염 유발군과 정상군 사이에 큰 차이가 보이지 않았다. 그리고 골무기질 함량은 정상군에 비해 감소하지 않았다. 20일 경과후 몸무게로 나누거나 나누지 않은 BMC치 모두, 관절염 군에서 요부 몸체의 골무기질 함량과 강도가 정상군과 비교해 볼 때 현저하게 감소되었다. 잔존 소주(小柱)의 무기질 침착 표면은 현저하게 감소하였으며 파골 세포의 수는 증가하였다. 초기부터 매일 Shinsu(B23)에 CPH 약침 투여(10, 20, $50{\mu}g/kg$)는 20일 경과후 만성적인 다리 부종을 현저하게 방지하였으며, 골 무기질함량, 골강도 및 소주골 형성등의 감소와 파골세포수 증가도 완화하였다. Adjuvant주사로 장애를 받았던 연령대비 요부 길이 증가도 유지되었다. 이러한 결과는 Adjuvant에 의한 관절염 실험용쥐의 2차적인 골관절염에서 충분히 요추 몸체뼈와 강도 감소를 나타내기 위해서는 적어도 20일이 필요하다는 것을 제시하였다. 본 결과로부터 CPH가 실험용쥐의 관절염에 대한 골체, 골강도 및 골대체율을 조절하는데 유효하게 작용하고 있음을 알 수 있었다.

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Effects of Mume Fructus on the Rat Hypothyroidism Induced by PTU(6-n-propyl-2-thiouracil) (PTU(6-n-propyl-2-thiouracil)로 유발된 Rat 갑상선 기능저하증에 미치는 烏梅의 효과)

  • Choi, Jae Young;Roh, Seong Soo;Park, Ji Ha;Koo, Jin Suk;Seo, Bu Il
    • The Korea Journal of Herbology
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    • v.30 no.4
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    • pp.109-119
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    • 2015
  • Objectives : The aim of this study was to evaluate the effect of aqueous extracts of Mume Fructus(MF) on the 6-n-propyl-2-thiouracil(PTU)-induced rat hypothyroidism.Methods : Aqueous extracts of MF(yield = 19.38%) were administered, once per day for 42 days from 2 weeks before starting of PTU treatment as an oral dose of 300 and 150 ㎎/㎏(body weight), and hypothyroidism was induced by daily subcutaneous treatment of PTU 10 ㎎/㎏ for 28 days. The changes in the body weight, thyroid gland weights, liver weight, serum levels of thyroid hormone-thyroid stimulating hormone(TSH), tri-iodothyronine(T3) and thyroxine(T4), total cholesterol, low density lipoprotein(LDL), high density lipoprotein(HDL) and triglyceride (TG), aspartate aminotransferase(AST), alanine aminotransferase(ALT), liver antioxidant defense system-lipid peroxidation, H2O2, superoxide dismutase(SOD) and catalase(CAT) were examined with histopathology of thyroid glands and liver.Results : Results were compared with LevoT40.5 ㎎/㎏ treated rats. MF extracts recovered from the decreases in the body weight, liver weight, T3and T4, TG, liver CAT activities as results of PTU treatment. And MF extracts recovered from the increases of thyroid gland weights, TSH, HDL contents, liver H2O2, AST as results of PTU treatment. In addition, these PTU-induced histopathological changes in thyroid glands and liver related to hypothyroidism were dramatically decreased by treatment of both different dosages of MF extract, respectively.Conclusions : According to the above results, it is suggested that MF extracts have advantageous effects on the thyroid hormone productions with beneficial effects on the hypothyroidism related liver injuries mediated by the modulation on the antioxidant system.

Molecular Target Therapy of AKT and NF-kB Signaling Pathways and Multidrug Resistance by Specific Cell Penetrating Inhibitor Peptides in HL-60 Cells

  • Davoudi, Zahra;Akbarzadeh, Abolfazl;Rahmatiyamchi, Mohammad;Movassaghpour, Ali Akbar;Alipour, Mohsen;Nejati-Koshki, Kazem;Sadeghi, Zohre;Dariushnejad, Hassan;Zarghami, Nosratollah
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4353-4358
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    • 2014
  • Background: PI3/AKT and NF-kB signaling pathways are constitutively active in acute myeloid leukemia and cross-talk between the two has been shown in various cancers. However, their role in acute myeloid leukemia has not been completely explored. We therefore used cell penetrating inhibitor peptides to define the contributions of AKT and NF-kB to survival and multi drug resistance (MDR) in HL-60 cells. Materials and Methods: Inhibition of AKT and NF-kB activity by AKT inhibitor peptide and NBD inhibitor peptide, respectively, resulted in decreased expression of mRNA for the MDR1 gene as assessed by real time PCR. In addition, treatment of HL-60 cells with AKT and NBD inhibitor peptides led to inhibition of cell viability and induction of apoptosis in a dose dependent manner as detected by flow cytometer. Results: Finally, co-treatment of HL-60 cells with sub-optimal doses of AKT and NBD inhibitor peptides led to synergistic apoptotic responses in AML cells. Conclusions: These data support a strong biological link between NF-kB and PI3-kinase/AKT pathways in the modulation of antiapoptotic and multi drug resistant effects in AML cells. Synergistic targeting of these pathways using NF-kB and PI3-kinase/AK inhibitor peptides may have a therapeutic potential for AML and possibly other malignancies with constitutive activation of these pathways.

Local Cervical Immunity in Women with Low-grade Squamous Intraepithelial Lesions and Immune Responses After Abrasion

  • Ekalaksananan, Tipaya;Malat, Praphatson;Pientong, Chamsai;Kongyingyoes, Bunkerd;Chumworathayi, Bandit;Kleebkaow, Pilaiwan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.10
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    • pp.4197-4201
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    • 2014
  • Minor trauma to the uterine cervix is supposed to induce local immunity to prevent cervical lesions caused by human papillomavirus (HPV) infection. This study aimed to investigate the local cervical immunity in women with low grade squamous intraepithelial lesion (LSIL) and effects of abrasion after cryosurgery or Pap smear. One hundred women with LSIL and known results of HPV detection were recruited. HPV positive women were randomly divided according to abrasion into cryotherapy and Pap smear observation groups. Cervical tissues and cervico-vaginal lavage (CVL) were collected at 6 and 12 months after allocation. The levels of cytokines at first recruitment were compared with cytokine levels at 6 months after abrasions. The mRNA of IFN-${\gamma}$, TNF-${\alpha}$ and IL-10 in cervical tissues and these cytokines secreted in CVL were determined using real time PCR and ELISA, respectively. Anti-HPV16 IgG and IgA antibodies in CVL were assessed by western blotting. At first recruitment of women with LSIL (100 cases), IL-10 mRNA and cytokine in HPV positive group (60 cases) was significantly higher than negative group (40 cases). IFN-${\gamma}$ and TNF-${\alpha}$ mRNA level in both groups were comparable but their secretions in CVL were significantly increased in HPV negative group. After abrasion for 6 months in HPV-positive women, all mRNA and secreted cytokines were changed, but no significant difference was observed between cryotherapy and observation groups. When individuals were compared between first recruitment and after abrasion for 6 months, IFN-${\gamma}$ mRNA and anti-HPV16 L1 IgA antibodies were significantly increased in the cryotherapy group. The results suggest that modulation of local cervical immunities by abrasion might promote different effects in clearance of HPV-related cytological abnormalities.

The Effects of Vitex rotundifolia Linne fil. Extract on the Inflammatory and Allergic Reactions (만형자 추출물이 염증 및 알레르기 반응에 미치는 영향)

  • Yeon, Kyoung-Jin;Jung, Hyun-A;Roh, Seok-Seon
    • Journal of Haehwa Medicine
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    • v.22 no.1
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    • pp.145-170
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    • 2013
  • Objectives : This study was carried out to investigate the anti inflammatory and anti allergy effects of Vitex rotundifolia Linne fil. extract(VRE). Results : 1. In vitro test, VRE was used to determine the modulation of cytokine secretion, the activation of inflammatory and allergic factor and the inhibition of gene expression. The cell survival rate of Raw 264.7 and Jurkat T cells didn't decrease and accordingly cytotoxicity wasn't observed. In anti-allergic assay, the secretion of IL-2, TNF-${\alpha}$, IL-4, IL-5 and IFN-${\gamma}$ were suppressed on Jurkat T cells induced by dust mites. And the gene expression of COX-2 was suppressed in HMC-1 stimulated by calcium ionophore A23187. In anti-inflammatory assay, the gene expression of TNF-${\alpha}$, COX-2 were suppressed on LPS-activated Raw 264.7 cells. And the secretion of IL-6 and IL-8 were suppressed on EoL-1 cells induced by dust mites. P38 and ERK activation of MAPK decreased generally. VRE showed potent inhibitory activity of NO production. 2. In vivo test, we used NC/Nga mouse induced by atopic dermatitis to observe the effects of VRE on the weight, water and feed, blood test, weight of organs, total IgE and histological change of main organs. Quantity of water and feed were not changed, therefore it didn't affect the weight directly, and no change was observed in related main organs, thus maybe there is no organ toxicity by test substances. And the symptoms were decreased significantly, and the thickness of epithelial cell layer and the number of mast cells were inhibited significantly by the difference of dosage. The number of total complete blood cells and IgE in serum were not changed significantly. Conclusion : These results suggest that VRE has anti-inflammatory and anti-allergic effects. Therefore VRE could be used effectively on improvement or treatment of atopic dermatitis. However, further study is needed to prove which component of VRE indicates effective pharmacological action.

A Study on a Phase-encoded Multiplexing Method in Holographic Memory System (홀로그래픽 메모리시스템에서 위상 다중화 인코딩에 관한 연구)

  • Cho, Byung-Chul;Kim, Kyu-Tae;Gil, Sang-Keun;Kim, Eun-Soo
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.10
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    • pp.51-60
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    • 1999
  • For an effective phase-multiplexing in holographic memory system, four types of phase code used as reference beam are generated. In case of $32 {\times} 32$ address beam, a phase error with 0%, 5%, 10% 15%, 20%, and 25% error rate, is purposely added to the real phase values in order to consider the practical SLM's nonlinear characteristics of phase modulation in computer simulation, cross talks and SNRs are comparatively analysed for these phase-codes by the auto and cross-correlation. Pseudo-Random(PSR) Phase Code has the lowest cross-correlation mean value of 0.067 among four types of Phase Code, which means the SNR of the PSR is higher than other Phase Codes. Also, the standard deviation of the PSR phase code indicating the degree of recalled data degradation is the lowest value of 0.0113.

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A Study of Noncontact Heartbeat and Respiration Detection Using the Doppler Radar (도플러 레이더를 이용한 비접촉 방식의 심박 및 호흡 검출에 관한 연구)

  • Shin, Jae-Yeon;Cho, Sung-Pil;Jang, Byung-Jun;Park, Ho-Dong;Lee, Yun-Soo;Lee, Kyoung-Joung
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.46 no.1
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    • pp.1-9
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    • 2009
  • In this paper, a 2.4 GHz doppler radar system consisting of a doppler radar sensor and a baseband module were designed to detect heart beat and respiration signal without direct skin contact. The doppler radar system emits RF signal of 2.4 GHz toward human chest, and then detects phase modulation of the reflected signal so as to investigate cardiopulmonary activities. The heartbeat and respiration signals acquired from I/Q channels of the doppler radar system are applied to the pre-processing circuit, the amplification circuit, and the offset circuit of the baseband module. The designed system was tested on mouse, rabbit and mankind, which have different range of heart rates and respiration signals, to evaluate detection accuracy of the system. ECG acquisition system and respiration transducer were used to generate the reference signal. In our experiments, a performance of detection were found to be high in the case that the subject stays still. In this paper, we confirmed that non-contact heart beat and respiration detection using the doppler radar has the possibility and limitation according to distance, cardiopulmonary activities, range of heart rates and respiration.

New SNR Estimation Algorithm using Preamble and Performance Analysis (프리앰블을 이용한 새로운 SNR 추정 알고리즘 제안 및 성능 분석)

  • Seo, Chang-Woo;Yoon, Gil-Sang;Portugal, Sherlie;Hwang, In-Tae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.48 no.3
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    • pp.6-12
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    • 2011
  • The fast growing of the number of users requires the development of reliable communication systems able to provide higher data rates. In order to meet those requirements, techniques such as Multiple Input Multiple Out (MIMO) and Orthogonal Frequency Division multiplexing (OFDM) have been developed in the recent years. In order to combine the benefits of both techniques, the research activity is currently focused on MIMO-OFDM systems. In addition, for a fast wireless channel environment, the data rate and reliability can be optimized by setting the modulation and coding adaptively according to the channel conditions; and using sub-carrier frequency, and power allocation techniques. Depending on how accurate the feedback-based system obtain the channel state information (CSI) and feed it back to the transmitter without delay, the overall system performance would be poor or optimal. In this paper, we propose a Signal to Noise Ratio (SNR) estimation algorithm where the preamble is known for both sides of the transciever. Through simulations made over several channel environments, we prove that our proposed SNR estimation algorithm is more accurate compared with the traditional SNR estimation.

Performance Analysis of Adaptive Channel Estimation Scheme in V2V Environments (V2V 환경에서 적응적 채널 추정 기법에 대한 성능 분석)

  • Lee, Jihye;Moon, Sangmi;Kwon, Soonho;Chu, Myeonghun;Bae, Sara;Kim, Hanjong;Kim, Cheolsung;Kim, Daejin;Hwang, Intae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.8
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    • pp.26-33
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    • 2017
  • Vehicle communication can facilitate efficient coordination among vehicles on the road and enable future vehicular applications such as vehicle safety enhancement, infotainment, or even autonomous driving. In the $3^{rd}$ Generation Partnership Project (3GPP), many studies focus on long term evolution (LTE)-based vehicle communication. Because vehicle speed is high enough to cause severe channel distortion in vehicle-to-vehicle (V2V) environments. We can utilize channel estimation methods to approach a reliable vehicle communication systems. Conventional channel estimation schemes can be categorized as least-squares (LS), decision-directed channel estimation (DDCE), spectral temporal averaging (STA), and smoothing methods. In this study, we propose a smart channel estimation scheme in LTE-based V2V environments. The channel estimation scheme, based on an LTE uplink system, uses a demodulation reference signal (DMRS) as the pilot symbol. Unlike conventional channel estimation schemes, we propose an adaptive smoothing channel estimation scheme (ASCE) using quadratic smoothing (QS) of the pilot symbols, which estimates a channel with greater accuracy and adaptively estimates channels in data symbols. In simulation results, the proposed ASCE scheme shows improved overall performance in terms of the normalized mean square error (NMSE) and bit error rate (BER) relative to conventional schemes.