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High-quality K(Fe1-xCox)2As2 single crystals have been grown by using the KAs flux method. Instead of increasing the superconducting transition temperature Tc through electron doping, we find that Co impurities rapidly suppress Tc down to zero at only x ≈ 0.04. Such an effective suppression of Tc by impurities is quite different from that observed in Ba0.5K0.5Fe2As2 with multiple nodeless superconducting gaps. Thermal conductivity measurements in zero field show that the residual linear term K0/T only changes slightly with 3.4% Co doping, despite the sharp increase in the scattering rate. The implications of these anomalous impurity effects are discussed. [ABSTRACT FROM AUTHOR]

The thermal conductivity κ of the superconductor Ir1−xPtxTe2 (x = 0.05) single crystal with strong spin-orbital coupling was measured down to 50 mK. The residual linear term is negligible in zero magnetic field. In low magnetic field, shows a slow field dependence. These results demonstrate that the superconducting gap of Ir1−xPtxTe2 is nodeless, and the pairing symmetry is likely a conventional s-wave, despite the existence of strong spin-orbital coupling and a quantum critical point. [ABSTRACT FROM AUTHOR]

We report resistivity ρ and thermal conductivity K measurements on Ca³Ir4Sn13 single crystals, in which superconductivity with Tc ≈ 7 K was claimed to coexist with ferromagnetic spin fluctuations. Among three crystals, only one crystal shows a small hump in resistivity near 20 K, which was previously attributed to the ferromagnetic spin fluctuations. The other two crystals show the ρ ~ T² Fermi-liquid behavior at low temperature. For both single crystals with and without the resistivity anomaly, the residual linear term K0/ T is negligible in zero magnetic field. In low fields, K0(H)/T shows a slow field dependence. These results demonstrate that the superconducting gap of Ca3lr4Sn13 is nodeless and thus rule out a nodal gap caused by ferromagnetic spin fluctuations. [ABSTRACT FROM AUTHOR]

The in-plane thermal conductivity κ of electron-doped iron-arsenide superconductor BaFe1.9Ni0.1As2 (Tc = 20.3 K) single crystal was measured down to 70 mK. In zero field, the absence of a residual linear term κ0/T at T → 0 is strong evidence for a nodeless superconducting gap. In magnetic field, κ0/T shows a slow field dependence up to H = 14.5 T (≈30% Hc2 ). This is consistent with the superconducting gap structure demonstrated by angle-resolved photoemission spectroscopy experiments in BaFe1.85Co0.15As2 (Tc = 25.5 K), where isotropic superconducting gaps with similar size on hole and electron pockets were observed. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to observe the efficacy and toxicity of etoposide at two dose levels for peripheral blood stem cell (PBSC) mobilization and disease debulking in patients with malignancy. Simultaneously, factors affecting the yield of CD34+ cells were explored. Methods Thirty-eight patients received etoposide 1.0 g/m2 (group A) or 1.5 g/m2 (group B) followed by granulocyte colony-stimulating factor (G-CSF) 300 µg/day for PBSC mobilization in a non-randomized manner. Each group had 19 patients. Results The median number of CD34+ cells collected was 17.33×106/kg (range 4.85-89.00×106/kg) in group A and 26.54×106/kg (range 1.85-108.00×106/kg) in group B. Altogether, 34/38 (89.5%) patients obtained the target total collection of at least 4×106 CD34+ cells/kg by a single leukapheresis. Vomiting was the most common grade 3/4 non-hematologic toxicity. For 19 evaluable patients, partial response was achieved in four (21.1%), stable disease in 11 (57.8%) and progressive disease in four (21.1%) patients. All parameters between the two groups did not reach a significant level. With multivariate analysis, the most predictive factor for CD34+ yield of the first leukapheresis was the percentage of CD34+ CD38- cells in peripheral blood. Conclusion These results indicate that etoposide combined with G-CSF is an effective and tolerable regimen for PBSC mobilization, given at a dose of either 1.0 g/m2 or 1.5 g/m2. [ABSTRACT FROM AUTHOR]

AimTo investigate the association between chronic hepatitis C virus (HCV) infection and Mooren's ulcer.MethodsEight patients from different parts of China who were diagnosed with Mooren's ulcer at the Zhongshan Ophthalmic Center, Guangzhou (China) were screened for chronic HCV infection. Mooren's ulcer was diagnosed by the typical ulcer morphology, detailed case history, physical examination, and comprehensive laboratory tests. All patients had serological screening for HCV infection.ResultsSix male and two female patients were enrolled in the study. Their ages ranged from 31 to 65 years (mean 43.6±13.7). None of them was reported to have any clinical evidence of chronic HCV infection before enrolment and all were negative for HCV serology.ConclusionThere was no association between chronic HCV infection and Mooren's ulcer in this limited case series study.Eye (2008) 22, 697–700; doi:10.1038/sj.eye.6702788; published online 6 July 2007 [ABSTRACT FROM AUTHOR]

High quality epitaxial thin films of FeSe1-xTe_x (x=0–1) have been successfully fabricated. Their superconducting transition temperatures are around 8–13 K. Microwave properties of a film (x=0.7) was studied by a sapphire dielectric cavity at 9.315 GHz. The cavity, which has a quality factor of 45000 in room temperature with TE011-mode, is specially designed for the measurement of small samples with the sapphire cylinder having a small hole in the center. Thin film samples with dimension of 1–2 mm can be put in the middle of the hole, supported by a very thin sapphire rod. The cavity is sealed in a vacuum chamber soaked in the liquid ^4He and the temperature of the thin sapphire rod (hence the sample) can be controlled from 1.6 K to 60 K with a stability about \pm1 mK. Temperature dependence of transmission response and Q-factors were measured by a network analyser (Agilent N5230C). The results showed a clear signature of multi-gap superconductivity. No evidences of existence of node in the energy gap were found as the normalized change in the surface reactance and the corresponding normalized change in the in-plane penetration depth have flat dependence at low temperatures. [ABSTRACT FROM AUTHOR]