21,789 research outputs found

    Theoretical studies of the local structures and EPR parameters for Cu2+^{2+} center in Cd2_{2}(NH4_{4})2_{2}(SO4_{4})3_{3} single crystal

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    The electron paramagnetic resonance (EPR) parameters (gg factors gig_{i} and the hyperfine structure constants Ai{{A}}_{{i}}, i=x,y,z{i} = {x}, {y}, {z}) are interpreted by using the perturbation formulae for a 3d93{d}^{9} ion in rhombically ({D}2h_{2h}) elongated octahedra. In the calculated formulae, the crystal field parameters are set up from the superposition model, and the contribution to the EPR parameters from the admixture of dd-orbitals in the ground state wave function of the Cu2+^{2+} ion was taken into account. Based on the calculation, local structural parameters of the impurity Cu2+^{2+} center in Cd2_{2}(NH4_{4})2_{2}(SO4_{4})3_{3} (CAS) crystal were obtained (i.e., Rx2.05{R}_{{x}}\approx 2.05 {\AA}, Ry1.91{R}_{{y}} \approx 1.91 {\AA}, Rz2.32{R}_{{z}} \approx 2.32 {\AA}). The theoretical EPR parameters based on the above Cu2+^{2+}-O2^{2-} bond lengths in CAS crystal show a good agreement with the observed values. The results are discussed.Comment: 5 page

    Hooge's Constant of Carbon Nanotube Field Effect Transistors

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    The 1/f noise in individual semiconducting carbon nanotubes (s-CNT) in a field effect transistor configuration has been measured in ultra-high vacuum and following exposure to air. The amplitude of the normalized current spectral noise density is independent of source-drain current, indicating the noise is due to mobility rather than number fluctuations. Hooge's constant for s-CNT is found to be 9.3 plus minus 0.4x10^-3. The magnitude of the 1/f noise is substantially degreased by exposing the devices to air

    Integrability of the critical point of the Kagom\'e three-state Potts mode

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    The vicinity of the critical point of the three-state Potts model on a Kagom\'e lattice is studied by mean of Random Matrix Theory. Strong evidence that the critical point is integrable is given.Comment: 1 LaTex file + 3 eps files 7 page

    Examining the role of socioeconomic deprivation in ethnic differences in sexually transmitted infection diagnosis rates in England: evidence from surveillance data

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    Differences by ethnic group in STI diagnosis rates have long been recognized in England. We investigated whether these may be explained by ethnic disparities in socioeconomic deprivation (SED). Data on all diagnoses made in sexual health clinics in England in 2013 were obtained from the mandatory STI surveillance system. Poisson regression was used to calculate incidence rate ratios (IRRs) of STIs, by ethnicity, with and without adjustment for index of multiple deprivation (IMD) a measure of area-level deprivation. Unadjusted IRRs (95% confidence intervals) were highest for gonorrhoea [8·18 (7·77-8·61) and 5·76 (5·28-6·29)] and genital herpes [4·24 (3·99-4·51) and 3·58 (3·23-3·98)] for people of black Caribbean and non-Caribbean/non-African black ethnicity and IRRs were highest for syphilis [8·76 (7·97-9·63)] and genital warts [2·23 (2·17-2·29)] for people of non-British/non-Irish white ethnicity compared to white British ethnicity. After adjustment for IMD, IRRs for gonorrhoea [5·76 (5·47-6·07)] and genital herpes [3·73 (3·50-3·97)] declined but remained highest for black Caribbeans and IRRs for syphilis [7·35 (6·68-8·09)] and genital warts [2·10 (2·04-2·16)] declined but remained highest for non-British/non-Irish white compared to white British. In England, ethnic disparities in STI diagnosis rates are partially explained by SED, but behavioural and contextual factors likely contribute. Clinic and community-based interventions should involve social peer networks to ensure they are targeted and culturally sensitive

    A study on nitrogen removal efficiency of Pseudomonas stutzeri strains isolated from an anaerobic/anoxic/oxic wastewater treatment process

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    In order to improve the nitrogen removal efficiency in an anaerobic/anoxic/oxic treatment plant, a strain with high nitrification and denitrification capability was isolated from a specific anaerobic/anoxic/oxic treatment process. The characteristics of isolate were experimentally analyzed. By using the nitrogen balance method, the total nitrogen loss was calculated to be 40.1% (w/w) when the carbon source was citric acid with a C/N ratio of 5. Meanwhile, the isolated strain was identified by 16S rDNA to be a Pseudomonas stutzeri with a similarity of 99%. Varying the initial TN, the C/N, the pH value and the ambient temperature in the reaction system, the efficiency of nitrogen removal was studied. The results showed that the highest efficiency occurred when the C/N was 12, the pH value was 7 and the temperature was 32°C. The results were also compared to the practically monitoring data coming with a good agreement. Consequently, it is viable to improve the nitrogen removal efficiency by varying the reaction conditions

    Quantum Lightning Never Strikes the Same State Twice

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    Public key quantum money can be seen as a version of the quantum no-cloning theorem that holds even when the quantum states can be verified by the adversary. In this work, investigate quantum lightning, a formalization of "collision-free quantum money" defined by Lutomirski et al. [ICS'10], where no-cloning holds even when the adversary herself generates the quantum state to be cloned. We then study quantum money and quantum lightning, showing the following results: - We demonstrate the usefulness of quantum lightning by showing several potential applications, such as generating random strings with a proof of entropy, to completely decentralized cryptocurrency without a block-chain, where transactions is instant and local. - We give win-win results for quantum money/lightning, showing that either signatures/hash functions/commitment schemes meet very strong recently proposed notions of security, or they yield quantum money or lightning. - We construct quantum lightning under the assumed multi-collision resistance of random degree-2 systems of polynomials. - We show that instantiating the quantum money scheme of Aaronson and Christiano [STOC'12] with indistinguishability obfuscation that is secure against quantum computers yields a secure quantum money schem

    PCN36 COST-MINIMIZATION ANALYSIS OF CAPECITABINE FOR ADVANCED GASTRIC CANCER IN TAIWAN

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    Sliding charge density wave in manganites

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    The so-called stripe phase of the manganites is an important example of the complex behaviour of metal oxides, and has long been interpreted as the localisation of charge at atomic sites. Here, we demonstrate via resistance measurements on La_{0.50}Ca_{0.50}MnO_3 that this state is in fact a prototypical charge density wave (CDW) which undergoes collective transport. Dramatic resistance hysteresis effects and broadband noise properties are observed, both of which are typical of sliding CDW systems. Moreover, the high levels of disorder typical of manganites result in behaviour similar to that of well-known disordered CDW materials. Our discovery that the manganite superstructure is a CDW shows that unusual transport and structural properties do not require exotic physics, but can emerge when a well-understood phase (the CDW) coexists with disorder.Comment: 13 pages; 4 figure

    Effect of nonstationarities on detrended fluctuation analysis

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    Detrended fluctuation analysis (DFA) is a scaling analysis method used to quantify long-range power-law correlations in signals. Many physical and biological signals are ``noisy'', heterogeneous and exhibit different types of nonstationarities, which can affect the correlation properties of these signals. We systematically study the effects of three types of nonstationarities often encountered in real data. Specifically, we consider nonstationary sequences formed in three ways: (i) stitching together segments of data obtained from discontinuous experimental recordings, or removing some noisy and unreliable parts from continuous recordings and stitching together the remaining parts -- a ``cutting'' procedure commonly used in preparing data prior to signal analysis; (ii) adding to a signal with known correlations a tunable concentration of random outliers or spikes with different amplitude, and (iii) generating a signal comprised of segments with different properties -- e.g. different standard deviations or different correlation exponents. We compare the difference between the scaling results obtained for stationary correlated signals and correlated signals with these three types of nonstationarities.Comment: 17 pages, 10 figures, corrected some typos, added one referenc

    Temperature dependence of Vortex Charges in High Temperature Superconductors

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    Using a model Hamiltonian with d-wave superconductivity and competing antiferromagnetic (AF) interactions, the temperature (T) dependence of the vortex charge in high T_c superconductors is investigated by numerically solving the Bogoliubov-de Gennes equations. The strength of the induced AF order inside the vortex core is T dependent. The vortex charge could be negative when the AF order with sufficient strength is present at low temperatures. At higher temperatures, the AF order may be completely suppressed and the vortex charge becomes positive. A first order like transition in the T dependent vortex charge is seen near the critical temperature T_{AF}. For underdoped sample, the spatial profiles of the induced spin-density wave and charge-density wave orders could have stripe like structures at T < T_s, and change to two-dimensional isotropic ones at T > T_s. As a result, a vortex charge discontinuity occurs at T_s.Comment: 5 pages, 5 figure
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