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The electron-doped cuprates are usually characterized by a more robust antiferromagnetic phase and a much narrower superconducting (SC) dome than those of the hole-doped counterparts. Recently, bulk single crystals of Pr_{1.3−x}La_{0.7}Ce_{x}CuO_{4−δ} (PLCCO) prepared by the protect annealing method have been studied extensively and revealed many intriguing properties that were different from those obtained from samples annealed by the conventional methods. Here we report on a systematic angle-resolved photoemission spectroscopy study of PLCCO single crystals after protect annealing. The results indicate that the actual electron concentration (n_{FS}) estimated from the Fermi-surface area is significantly larger than the Ce concentration x and the new n_{FS}-based SC dome of PLCCO is more extended towards the overdoped side than the x-based SC dome derived for samples prepared using the conventional annealing method.

In cuprates, superconductivity exists in a narrow window at high electron doping concentration with strong antiferromagnetic correlations. Here, the authors demonstrate superconductivity with no effect of antiferromagnetic order in a cuprate for a wide electron doping range following a protect anneal process.

We compute the contribution from the twist-3 fragmentation function for light hadron production in collisions between transversely and longitudinally polarized protons, i.e., p↑p→→hX, which can cause a double-spin asymmetry (DSA) ALT. This is a naïve T-even twist-3 observable that we analyze in collinear factorization using both Feynman gauge and lightcone gauge as well as give a general proof of color gauge invariance. So far only twist-3 effects in the transversely polarized proton have been studied for ALT in p↑p→→hX. However, there are indications that the naïve T-odd transverse single-spin asymmetry (SSA) AN in p↑p→hX is dominated not by such distribution effects but rather by a fragmentation mechanism. Therefore, one may expect similarly that the fragmentation contribution is important for ALT. Given possible plans at RHIC to measure this observable, it is timely to provide a calculation of this term.

Mirrorless graded-index polymer optical fibers doped with the organic dye rhodamine 6G result in very compact broadband fiber lasers in the visible region when pumped from the side. The emission spectrum, threshold, and efficiency obtained on both fiber ends depend on the lengths of the directly illuminated region and of the non-excited ones. The paper analyzes such parameters both experimentally and theoretically for the first time.

We present results for transverse single-spin asymmetries in proton-proton collisions at kinematics relevant for AFTER, a proposed fixed-target experiment at the Large Hadron Collider. These include predictions for pion, jet, and direct photon production from analytical formulas already available in the literature. We also discuss specific measurements that will benefit from the higher luminosity of AFTER, which could help resolve an almost 40-year puzzle of what causes transverse single-spin asymmetries in proton-proton collisions.

The aim of this paper is to design a human–interface system, using EMG signals elicited by various wrist movements, to control a robot. EMG signals are normalized and based on joint torque. A three-layer neural network is used to estimate posture of the wrist and forearm from EMG signals. After training the neural network and obtaining appropriate weights, the subject was able to control the robot in real time using wrist and forearm movements.

Abstract Genetic transformation was carried out with wild-type strains of Agrobacterium rhizogenes for introducing a dwarf trait into the Scrophulariaceous ornamental plant, angelonia (Angelonia salicariifolia). Leaf segments of two angelonia genotypes (Ang.1 and Ang.2) were co-cultivated with mikimopine-type strains of A. rhizogenes. Adventitious roots that showed vigorous growth and increased lateral branching when cultured on half-strength Murashige and Skoog's (MS) basal salts medium lacking plant growth regulators (PGRs) after co-cultivation were selected as putatively transformed lines. All of these selected lines produced mikimopine. Adventitious shoots were efficiently induced from putatively transformed root segments on half-strength MS basal salts medium containing 1 mg l-1 benzyladenine (BA) under continuous illumination (24-h photoperiod), and the shoots easily rooted following their transfer to half-strength MS basal salts medium lacking PGRs. The transgenic nature of regenerated plants was confirmed by Southern hybridization. Transformed plants frequently died during their acclimatization, and acclimatized plants of eight transformed lines grew very slowly for 1-5 months after transplantation to the greenhouse. Plants of two transformed lines of Ang.2 flowered 4-6 months after transplantation. These transformed plants exhibited phenotypic alterations such as dwarfness and smaller leaves. There were no apparent alterations observed in the number, shape, and size of the flowers. Pollen fertility of the transformed plants was 60-80% based on aceto-carmine staining. These results indicate the possibility of applying A. rhizogenes-mediated transformation for introducing a dwarf trait into angelonia. [ABSTRACT FROM AUTHOR]

Abstract We have investigated in detail dependence on p (the hole concentration per Cu) of the transport properties and Tc in the excess-oxygen-doped La2-xAxCuO4+d (A=Nd, Bi, Pr), where the phase separation of the excess oxygen is suppressed. The so-called 1/8 anomaly has been found in La1.8Nd0.2CuO4+d. The 1/8 anomaly has become marked through the 1% substitution of Zn for Cu. The µSR measurements have revealed that the magnetic correlation develops at low temperatures below about 40 K in both Zn-free and 1% Zn-substituted samples with p=1/8 and that a long-range magnetic order is formed below 1 K in the 1% Zn-substituted sample with p=1/8. These results support the stripe-pinning model. Neither La2-xBixCuO4+d nor La2-xPrxCuO4+d has exhibited the clear 1/8 anomaly. [ABSTRACT FROM AUTHOR]

Abstract Muon-spin-relaxation (µSR) and magnetic susceptibility measurements have been carried out in La2-xSrxCu1-yZnyO4 with x=0.13 changing y finely up to 0.10, with the aim at clarifying effects of the non-magnetic impurity Zn on the Cu-spin dynamics and superconductivity. It has been found that the y dependence of the volume fraction of the superconducting region estimated from susceptibility measurements highly correlates with that of the magnetically ordered region estimated from the µSR results. The rapid decrease in the superconducting region and the rapid increase in the magnetically ordered region by the doping of a small amount of Zn can be interpreted as follows; Zn pins the dynamical spin correlation or the dynamical stripe correlations and hence the superconductivity is destroyed around itself. [ABSTRACT FROM AUTHOR]

Objectives: To elucidate the factors associated with severity of cardiac sympathetic nerve involvement in idiopathic Parkinson's disease (PD). Methods: 123I-metaiodobenzylguanidine uptake was examined in 88 patients with PD. The ratio of the uptake in the heart (H) to that in the mediastinum (M) (the H/M ratio) was calculated and correlated with age at onset, age at examination, and disease severity and duration. Twenty five healthy people were also examined as a control. Results: There was a mild but significant negative correlation between H/M ratio and age at onset (early, r = -0.33, p = 0.002; delayed, r = -0.34, p = 0.001) and between Hoehn and Yahr (H-Y) stage (early, r = -0.30, p = 0.006; delayed, r = -0.32, p = 0.003). There was no significant correlation between disease duration and H/M ratio. When patients with PD were classified into four subgroups on the basis of age at onset (> 62 or < 62 years) and disease severity (H-Y > III or H-Y ≤ II), the median H/M ratio of the older and more severe group was significantly lower than that of the younger and less severe group (p = 0.005). Conclusion: This study suggests that late onset, high severity PD is associated with myocardial sympathetic dysfunction. [ABSTRACT FROM AUTHOR]

We investigated the way to reduce the mode coupling (the energy transfer among the propagating modes) in a multimode fiber. It strongly influences the bandwidth in the graded-index plastic optical fiber (GI POF), and it was found that the mode-coupling strength in the GI POF depended on the numerical aperture of the fiber. Moreover, we propose a new optimum waveguiding design of GI POFs when only small mode groups are launched [under filled launch condition (UFL)], which is expected in a real high-speed GI POF link. We demonstrate greater than 1-GHz transmission by a 250-m polymethylmethacrylate (PMMA-d8)-based GI POF under the UFL condition. [ABSTRACT FROM PUBLISHER]

A plastic optical fiber having a W-shaped refractive index profile [W-shaped plastic optical fiber (POF)] was prepared for the first time to realize a higher bit rate transmission than those of the conventional silica-based multimode fiber and graded-index (GI) POF links. Since the W-shaped POF has a valley of the refractive index at the boundary of the core and cladding of the conventional GI POF, the group delay of higher order modes is strongly influenced, thus compensating the modal dispersion that exists in the GI POF. The modal dispersion compensation effect by the W-shaped index profile was theoretically and experimentally confirmed. [ABSTRACT FROM PUBLISHER]

A full-duplex data link at 10 Gbit/s per channel (two upstream and two downstream) between two compact bidirectional optical sub-assemblies is presented. Each sub-assembly is based on the authors' optoelectronic ferrule and carries both laser diodes and photodiodes while maintaining a compact form factor of less than 20 mm3. The authors use plastic optical fibres with 50 μm graded-index cores and thin 125 μm claddings bundled in a four-channel ribbon but split the ribbon in order to reach both laser diodes and photodiodes within the optoelectronic ferrule, hence directly butt-coupling each channel with its own optical fibre. This method keeps both assembly form factor and complexity at a minimum and performance high. Eventually error-free signal transmission at 10 Gbit/s per channel over 5 m with 0.67 unit intervals eye opening is confirmed. [ABSTRACT FROM AUTHOR]

We have investigated the electronic structure of superconducting (SC) and nonsuperconducting (non-SC) KxFe2-ySe2 using x-ray photoemission spectroscopy (XPS). The spectral shape of the Fe 2p XPS is found to depend on the amount of Fe vacancies. The Fe 2p3/2 peak of the SC and non-SC Fe-rich samples is accompanied by a shoulder structure on the lower binding energy side, which can be attributed to the metallic phase embedded in the Fe2+ insulating phase. The absence of the shoulder structure in the non-SC Fe-poor sample allows us to analyze the Fe 2p spectra using a FeSe4 cluster model. The Fe 3d-Se Ap charge-transfer energy of the Fe2- insulating phase is found to be ∼2.3 eV which is smaller than the Fe 3d-Fe 3d Coulomb interaction of ∼3.5 eV. This indicates that the Fe2+ insulating state is the charge-transfer type in the Zaanen-Sawatzky-Allen scheme. We also find a substantial change in the valence-band XPS as a function of Fe content and temperature. The metallic state at the Fermi level is seen in the SC and non-SC Fe-rich samples and tends to be enhanced with cooling in the SC sample. [ABSTRACT FROM AUTHOR]