275 research outputs found

    Design of Quantum error correcting code for biased error on heavy-hexagon structure

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    Surface code is an error-correcting method that can be applied to the implementation of a usable quantum computer. At present, a promising candidate for a usable quantum computer is based on superconductor-specifically transmon. Because errors in transmon-based quantum computers appear biasedly as Z type errors, tailored surface and XZZX codes have been developed to deal with the type errors. Even though these surface codes have been suggested for lattice structures, since transmons-based quantum computers, developed by IBM, have a heavy-hexagon structure, it is natural to ask how tailored surface code and XZZX code can be implemented on the heavy-hexagon structure. In this study, we provide a method for implementing tailored surface code and XZZX code on a heavy-hexagon structure. Even when there is no bias, we obtain 0.231779% 0.231779 \% as the threshold of the tailored surface code, which is much better than 0.210064% 0.210064 \% and 0.209214% 0.209214 \% as the thresholds of the surface code and XZZX code, respectively. Furthermore, we can see that even though a decoder, which is not the best of the syndromes, is used, the thresholds of the tailored surface code and XZZX code increase as the bias of the Z error increases. Finally, we show that in the case of infinite bias, the threshold of the surface code is 0.264852% 0.264852\%, but the thresholds of the tailored surface code and XZZX code are 0.296157% 0.296157 \% and 0.328127% 0.328127 \% respectively

    Vapor liquid equilibrium measurements for clean fuel processes

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    This thesis is based on seven publications dealing with the Vapor Liquid Equilibrium (VLE) measurements which are necessary for pure components process. Two VLE measurements sections were comprised in this thesis. Firstly, VLE runs were conducted with a circulation still at both atmospheric pressure and isothermal conditions under low atmospheric pressure. Secondly, the static apparatus has been used in isothermal VLE for six binary pairs of C4 hydrocarbons and 2-propanone in a range from 69.6 kPa to 610.9 kPa. In addition, the VLE modeling was considered to determine the parameters in thermodynamic models. The selected components are in area of great industrial interest in view of developing gasoline additives to replace MTBE (2-methoxy-2-methylpropane), such as transform old MTBE plants to produce isooctene. Especially ETBE (2-Ethoxy-2-methylpropane) has emerged as an alternative to MTBE, because ETBE can be produced from ethanol made of renewable resources. The experimental data were correlated using activity coefficient models for the liquid phase and equation of state (EOS) for the vapor phase. These models were also compared with a predictive activity coefficient models. The estimations made with various different predictive coefficient models gave worse description of the measurements than by fitting the data with the Wilson equation. The experimental apparatus and the procedure presented were shown to be reliable, particularly the computer-controlled static apparatus. Moreover, these results seem to be reliable since they passed thermodynamic consistency tests. Most VLE and excess enthalpy measurements in this thesis are for binary systems that have not been measured previously.reviewe

    マキシマムエントロピー法による静電ポテンシャルフラグメント解析法の強誘電分極解析への応用

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    学位の種別: 課程博士審査委員会委員 : (主査)東京大学客員教授 高田 昌樹, 東京大学教授 雨宮 慶幸, 東京大学教授 木村 薫, 東京大学教授 有馬 孝尚, 東京大学教授 岩佐 義宏, 東京大学教授 佐々木 裕次University of Tokyo(東京大学

    Glycogen synthase kinase 3 beta suppresses polyglutamine aggregation by inhibiting Vaccinia-related kinase 2 activity

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    Huntington's disease (HD) is a neurodegenerative disorder caused by an abnormal expansion of polyglutamine repeats in the N-terminal of huntingtin. The amount of aggregate-prone protein is controlled by various mechanisms, including molecular chaperones. Vaccinia-related kinase 2 (VRK2) is known to negatively regulate chaperonin TRiC, and VRK2-facilitated degradation of TRiC increases polyQ protein aggregation, which is involved in HD. We found that VRK2 activity was negatively controlled by glycogen synthase kinase 3 beta (GSK3 beta). GSK3 beta directly bound to VRK2 and inhibited the catalytic activity of VRK2 in a kinase activity-independent manner. Furthermore, GSK3 beta increased the stability of TRiC and decreased the formation of HttQ103-GFP aggregates by inhibiting VRK2. These results indicate that GSK3 beta signaling may be a regulatory mechanism of HD progression and suggest targets for further therapeutic trials for HD.1131Ysciescopu

    Kondo-like behaviors in magnetic and thermal properties of single crystal Tm5Si2Ge2

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    We grew the single crystal of stoichiometric Tm5Si2.0Ge2.0 using a Bridgeman method and performed XRD, EDS, magnetization, ac and dc magnetic susceptibilities, specific heat, electrical resistivity and XPS experiments. It crystallizes in orthorhombic Sm5Ge4-type structure. The mean valence of Tm ions in Tm5Si2.0Ge2.0 is almost trivalent. The 4f states is split by the crystalline electric field. The ground state exhibits the long range antiferromagnetic order with the ferromagnetically coupled magnetic moments in the ac plane below 8.01 K, while the exited states exhibit the reduction of magnetic moment and magnetic entropy and -log T-behaviors observed in Kondo materials.Comment: 8 pages, 13 figure

    Biological Responses to Diesel Exhaust Particles (DEPs) Depend on the Physicochemical Properties of the DEPs

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    Diesel exhaust particles (DEPs) are the main components of ambient particulate materials, including polyaromatic hydrocarbons (PAHs), n-PAHs, heavy metals, and gaseous materials. Many epidemiological, clinical, and toxicological studies have shown that ambient particles, including DEPs, are associated with respiratory disorders, such as asthma, allergic rhinitis, and lung cancer. However, the relationship between the biological response to DEPs and their chemical composition remains unclear. In this study, we investigated the physicochemical properties of DEPs before toxicological studies, and then administered a single intratracheal instillation of DEPs to mice. The mice were then killed 1, 7, 14 and 28 days after DEP exposure to observe the biological responses induced by DEPs over time. Our findings suggest that DEPs engulfed into cells induced a Th2-type inflammatory response followed by DNA damage, whereas DEPs not engulfed into cells induced a Th1-type inflammatory response. Further, the physicochemical properties, including surface charge, particle size, and chemical composition, of DEPs play a crucial role in determining the biological responses to DEPs. Consequently, we suggest that the biological response to DEPs depend on cell-particle interaction and the physicochemical properties of the particles

    Biological Toxicity and Inflammatory Response of Semi-Single-Walled Carbon Nanotubes

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    The toxicological studies on carbon nanotubes (CNTs) have been urgently needed from the emerging diverse applications of CNTs. Physicochemical properties such as shape, diameter, conductance, surface charge and surface chemistry of CNTs gained during manufacturing processes play a key role in the toxicity. In this study, we separated the semi-conductive components of SWCNTs (semi-SWCNTs) and evaluated the toxicity on days 1, 7, 14 and 28 after intratracheal instillation in order to determine the role of conductance. Exposure to semi-SWCNTs significantly increased the growth of mice and significantly decreased the relative ratio of brain weight to body weight. Recruitment of monocytes into the bloodstream increased in a time-dependent manner, and significant hematological changes were observed 28 days after exposure. In the bronchoalveolar lavage (BAL) fluid, secretion of Th2-type cytokines, particularly IL-10, was more predominant than Th1-type cytokines, and expression of regulated on activation normal T cell expressed and secreted (RANTES), p53, transforming growth factor (TGF)-β, and inducible nitric oxide synthase (iNOS) increased in a time-dependent manner. Fibrotic histopathological changes peaked on day 7 and decreased 14 days after exposure. Expression of cyclooxygenase-2 (COX-2), mesothelin, and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) also peaked on day 7, while that of TGF-β peaked on days 7 and 14. Secretion of histamine in BAL fluid decreased in a time-dependent manner. Consequently, we suggest that the brain is the target organ of semi-SWCNTs brought into the lung, and conductance as well as length may be critical factors affecting the intensity and duration of the inflammatory response following SWCNT exposure

    Deleterious effects in reproduction and developmental immunity elicited by pulmonary iron oxide nanoparticles

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    With the extensive application of iron oxide nanoparticles (FeNPs), attention about their potential risks to human health is also rapidly raising, particularly in sensitive subgroups such as pregnant women and babies. In this study, we a single instilled intratracheally FeNPs (1, 2, and 4 mg/kg) to the male and female parent mice, mated, then assessed reproductive toxicity according to the modified OECD TG 421. During the pre-mating period (14 days), two female parent mice died at 4 mg/kg dose, and the body weight gain dose-dependently decreased in male and female parent mice exposed to FeNPs. Additionally, iron accumulation and the enhanced expression of MHC class II molecules were observed in the ovary and the testis of parent mice exposed to the highest dose of FeNPs, and the total sex ratio (male/female) of the offspring mice increased in the groups exposed to FeNPs. Following, we a single instilled intratracheally to their offspring mice with the same doses and evaluated the immunotoxic response on day 28. The increased mortality and significant hematological- and biochemical- changes were observed in offspring mice exposed at 4 mg/kg dose, especially in female mice. More interestingly, balance of the immune response was shifted to a different direction in male and female offspring mice. Taken together, we conclude that the NOAEL for reproductive and developmental toxicity of FeNPs may be lower than 2 mg/kg, and that female mice may show more sensitive response to FeNPs exposure than male mice. Furthermore, we suggest that further studies are necessary to identify causes of both the alteration in sex ratio of offspring mice and different immune response in male and female offspring mice.
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