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Magnetotransport measurements were performed on a cross-junction made from polycrystalline graphene grown at a low temperature. The Shubnikov-de Haas oscillation is observed, from which the cyclotron mass mc can be derived varying from 0.043 to 0.055 times that of free electron. The changing rate of electron temperature is found much lower than that in pristine graphene via the universal electron heating study. Investigations on the characteristic lengths of weak localization reveal that the atomically sharp defects dominate the elastic scattering process, while studies on the coherent rate report that the Nyquist effect governs the inelastic scattering process with a little modulation from the direct Coulomb interaction. The scattering lengths in the polycrystalline graphene are comparable to that of exfoliated graphene on SiO2. These findings indicate that some key scattering parameters which characterize the excellent properties of intrinsic graphene are preserved in the polycrystalline graphene, which may find potential applications in interconnects of integrated circuit. [ABSTRACT FROM AUTHOR]

The ability of cultured peripheral-blood mononuclear cells (PBMC) to release interleukin-1 alpha and beta (IL-1 alpha, IL-1 beta) in response to concanavalin A (con A) was investigated in patients with chronic renal failure (CRF) and in renal transplant recipients. Mean IL-1 alpha level released by PBMC of healthy subjects (n = 42), CRF patients (n = 42), or transplants 2 months after operation (n = 69) was 152 +/- 103, 110 +/- 80, or 154 +/- 87 pg/5 x 10(5) cells/ml culture, respectively. IL-1 alpha release from PBMC of recipients 2 months after renal transplantation was significantly higher than that of CRF patients (p less than 0.05). Mean IL-1 beta level released by PBMC of healthy subjects (n = 34), CRF (n = 30), or transplants (n = 55) was 223 +/- 159, 135 +/- 129, or 276 +/- 155 pg/5 x 10(5) cells, respectively. Similar to IL-1 alpha, the level in CRF was significantly lower than that in healthy subjects (p less than 0.05). A time course study indicated that the ability of PBMC from transplants to release IL-1 alpha and beta promptly decreased following the operation, possibly owing to prednisolone and ciclosporin immunosuppressive therapy. However, after maintaining a low level for 2-3 weeks, IL-1 release from PBMC gradually increased thereafter. The results were consistent with known characteristics of decreased immunity in CRF states, and further suggested that the decreased ability of PBMC to release IL-1 alpha and beta in response to con A in CRF patients is recovered 2 months after renal transplantation.