• 제목/요약/키워드: High-$T_{c}$

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Folate intake, Methylenetetrahydrofolate Reductase Polymorphisms in Association with the Prognosis of Esophageal Squamous Cell Carcinoma

  • Jing, Chen;Huang, Zhijie;Duan, Yuqin;Xiao, Xinrong;Zhang, Ru;Jiang, Jianqing
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권2호
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    • pp.647-651
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    • 2012
  • Aim: An epidemiological study was conducted based on an esophageal cancer patient's cohort to investigate the association of folate intake and MTHFR C677T polymorphism with the prognosis of esophageal cancer in a Chinese population. Methods: 167 patients aged 37-75 years who had histological confirmed diagnosis of esophageal squamous cell cancer were collected from Jan. 2006 to Jan. 2008. MTHFR genotypes at the C677T site were analyzed by PCR-based RFLP methods, and the folate intake was computed by multiplying the food intake (in grams) and the folate content (per gram) of food in our questionnaire. Results: We found associations between the prognosis of esophageal cancer and smoking status, T and N stages. Individuals carrying the MTHFR 677CT and TT genotypes showed a shorter survival time than with the CC genotype, with adjusted HRs (95% CI) of 1.20 (0.56-2.15) and 2.29 (1.30-4.28), respectively. Similarly, those carrying MTHFR 677T allele had a 1.86-fold risk of death. A higher folate concentration showed a significant decreased risk of death, with an HR (95% CI) of 0.45 (0.18-0.87). Individuals with high folate intake and the MTHFR 677CC genotype showed a significant decreased risk of esophageal cancer (0.43, 0.25-0.89).Conclusion: Our findings supports the hypothesis that high folate intake and active MTHFR C677T polymorphism may exert protective roles in the prognosis of esophageal cancer in the Chinese population.

긴기저선을 가진 단일층 고온초전도 SQUID 2차미분기 (Long-baseline single-layer 2nd-order $high-T_c$ SQUID gradiometer)

  • 이순걸;강찬석;김인선;김상재
    • Progress in Superconductivity
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    • 제7권1호
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    • pp.6-10
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    • 2005
  • We have studied feasibility of single-layer second-order $high-T_c$ SQUID gradiometers in magnetocardiography. We have measured human cardiomagnetic signals using a short-baseline (5.8 mm) single-layer second-order YBCO gradiometer in partially shielded environments. The gradiometer has an overall size of $17.6\;mm{\times}6\;mm$ and contains three parallel-connected pickup coils which are directly coupled to a step-edge junction SQUID. The gradiometer showed an unshielded gradient noise of $0.84\;pT/cm^2/Hz^{1/2}$ at 1 Hz, which corresponds to an equivalent field noise of $280\;fT/Hz^{1/2}$. The balancing factor was $10^3$. Based on the same design rules as the short-baseline devices, we have studied fabrication of 30 mm-long baseline gradiometers. The devices had an overall size of $70.2\;mm{\times}10.6\;mm$ with each pickup coil of $10\;mm{\times}10\;mm$ in outer size. As Josephson elements we made two types of submicron bridges, which are variable thickness bridge (VTB) and constant thickness bridge (CTB), from $3\;{\mu}m-wide$ and 300 nm-thick YBCO lines with a thin layer of Au on top by using a focused ion beam (FIB) patterning method. VTB was 300 nm wide, 200 nm thick, 30 nm long with Au removed and CTB 100 nm wide and 30 nm long. In temperature-dependent critical currents, $I_c(T)$, VTB showed an nonmetallic barrier-type behavior and CTB an SNS behavior. We believe that those characteristics are ascribed to naturally formed grain boundaries crossing the bridges.

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In0.8Ga0.2As HEMT 소자에서 Output-conductance가 차단 주파수에 미치는 영향에 대한 연구 (Effect of Output-conductance on Current-gain Cut-off frequency in In0.8Ga0.2As High-Electron-mobility Transistors)

  • 노태범;김대현
    • 센서학회지
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    • 제29권5호
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    • pp.324-327
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    • 2020
  • The impact of output conductance (go) on the short-circuit current-gain cut-off frequency (fT) in In0.8Ga0.2As high-electron-mobility transistors (HEMTs) on an InP substrate was investigated. An attempted was made to extract the values of fT in a simplified small-signal model (SSM) of the HEMTs, derive an analytical formula for fT in terms of the extrinsic model parameters of the simplified SSM, which are related to the intrinsic model parameters of a general SSM, and verify its validity for devices with Lg from 260 to 25 nm. In long-channel devices, the effect of the intrinsic output conductance (goi) on fT was negligible. This was because, from the simplified SSM perspective, three model parameters, such as gm_ext, Cgs_ext and Cgd_ext, were weakly dependent on goi. However, in short-channel devices, goi was found to play a significant role in degrading fT as Lg was scaled down. The increase in goi in short-channel devices caused a considerable reduction in gm_ext and an overall increase in the total extrinsic gate capacitance, yielding a decrease in fT with goi. Finally, the results were used to infer how fT is influenced by goi in HEMTs, emphasizing that improving electrostatic integrity is also critical importance to benefit fully from scaling down Lg.

Genetic Diversity of Taenia asiatica from Thailand and Other Geographical Locations as Revealed by Cytochrome c Oxidase Subunit 1 Sequences

  • Anantaphruti, Malinee Thairungroj;Thaenkham, Urusa;Watthanakulpanich, Dorn;Phuphisut, Orawan;Maipanich, Wanna;Yoonuan, Tippayarat;Nuamtanong, Supaporn;Pubampen, Somjit;Sanguankiat, Surapol
    • Parasites, Hosts and Diseases
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    • 제51권1호
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    • pp.55-59
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    • 2013
  • Twelve 924 bp cytochrome c oxidase subunit 1 (cox1) mitochondrial DNA sequences from Taenia asiatica isolates from Thailand were aligned and compared with multiple sequence isolates from Thailand and 6 other countries from the GenBank database. The genetic divergence of T. asiatica was also compared with Taenia saginata database sequences from 6 different countries in Asia, including Thailand, and 3 countries from other continents. The results showed that there were minor genetic variations within T. asiatica species, while high intraspecies variation was found in T. saginata. There were only 2 haplotypes and 1 polymorphic site found in T. asiatica, but 8 haplotypes and 9 polymorphic sites in T.saginata. Haplotype diversity was very low, 0.067, in T. asiatica and high, 0.700, in T. saginata. The very low genetic diversity suggested that T. asiatica may be at a risk due to the loss of potential adaptive alleles, resulting in reduced viability and decreased responses to environmental changes, which may endanger the species.

고혈압 전단계 대학생들의 단순 일회성 유산소 운동이 혈압, 혈중지질과 섬유소 용해 인자에 미치는 영향 (Effects of Acute Aerobic Exercise on Blood Pressure, Blood Lipids and Fibrinolytic Markers in Pre-hypertension College-aged Males)

  • 김대열;백경엽;박혁;이하얀;김동희
    • 한국산학기술학회논문지
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    • 제18권7호
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    • pp.140-148
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    • 2017
  • 본 연구는 고혈압전단계 남자 대학생들이 단순 일회성 유산소 운동을 운동강도를 달리하여 혈압, 혈중지질, 섬유소용해 인자에 미치는 영향에 대하여 연구하였다. 총 6명이 최종 실험 참가자로 선정되어 일회성 달리기 운동을 저강도(50-60% 여유심박수(Heart rate reserve(HRR)), 중강도(60-70%HRR), 고강도(70-80%HRR)로 실시하였다. 혈압(수축기와 이완기), 혈중지질(총 콜레스테롤(total cholesterol(TC), 고밀도단백질 콜레스테롤(high-density lipoprotein cholesterol(HDL-C)), 섬유소 용해인자(tissue plasminogen activator(tPA) and plasminogen activator inhibitor-1(PAI-1))는 운동 전과 후 그리고 운동 후 60분 각각의 강도마다 측정되었다. 실험결과는 저강도 그룹의 수축기 혈압은 운동 후에 유의하게 상승하였다(p=0.013). 하지만 중강도와 고강도 그룹의 수축기 혈압은 유의미하지는 않았으나 효과크기로 분석시 운동 후 60분에 -1.33과 -1.23으로 큰 효과를 보이며 낮아졌다. HDL-C는 중강도(p=0.003)와 고강도 그룹(p=0.002)에서 운동 후 60분에 유의하게 증하였다. tPA는 중강(p=0.021)와 고강도 그룹이(p=0.042) 운동 후에 유의하게 증가하였다. 그리하여 일회성 중강도와 고강도 운동을 했을 때 운동 후 저혈압이 나타나고 HDL-C가 높아지고 또한 tPA 농도가 높아져서 고혈압 전 단계 젊은 남자들이 지속적인 중강도 이상의 운동을 하게 되면 고혈압과 심혈관질환을 예방하고 지연시킬 것이다.