Effective mass and band nonparabolicity in remote doped Si/Si0.8Ge0.2 quantum wells

The effective masses in remote doped Si/Si0.8Ge0.2/Si quantum wells having sheet densities, Ns in the range 2 × 1011–1.1 × 1012 cm – 2 have been determined from the temperature dependencies of the Shubnikov–de Haas oscillations. The values obtained increase with magnetic field and Ns. This behavior is taken as evidence for the nonparabolicity of the valence band and accounts for the discrepancies in previously reported masses. Self-consistent band structure calculations for a triangular confinement of the carriers have also been carried out and provide confirmation of the increase in mass with Ns. Theory and experiment give extrapolated Gamma point effective masses of 0.21 and 0.20 of the free-electron mass, respectively

CD28null CD4 T-cell expansions in autoimmune disease suggest a link with cytomegalovirus infection

Immunosenescence is thought to contribute to the increase of autoimmune diseases in older people. Immunosenescence is often associated with the presence of an expanded population of CD4 T cells lacking expression of CD28 (CD28null). These highly cytotoxic CD4 T cells were isolated from disease-affected tissues in patients with rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, or other chronic inflammatory diseases and their numbers appeared to be linked to disease severity. However, we recently demonstrated that the common herpes virus, cytomegalovirus (CMV), not ageing, is the major driver of this subset of cytotoxic T cells. In this review, we discuss how CMV might potentiate and exacerbate autoimmune disease through the expansion of CD28null CD4 T cells

Valence band engineering in semiconductor lasers

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Multi-biomarker disease activity score as a predictor of disease relapse in patients with rheumatoid arthritis stopping TNF inhibitor treatment

Contains fulltext : 193043.pdf (publisher's version ) (Open Access

Measuring Disease Exacerbation and Flares in Rheumatoid Arthritis: Comparison of Commonly Used Disease Activity Indices and Individual Measures

To evaluate and compare the utility of commonly used outcome measures for assessing disease exacerbation or flare in patients with rheumatoid arthritis (RA). Data from the Dutch Potential Optimalisation of (Expediency) and Effectiveness of Tumor necrosis factor-α blockers (POET) study, in which 462 patients discontinued their tumor necrosis factor-α inhibitor, were used. The ability of different measures to discriminate between those with and without physician-reported flare or medication escalation at the 3-month visit (T2) was evaluated by calculating effect size (ES) statistics. Responsiveness to increased disease activity was compared between measures by standardizing change scores (SCS) from baseline to the 3-month visit. Finally, the incremental validity of individual outcome measures beyond the Simplified Disease Activity Score was evaluated using logistic regression analysis. The SCS were greater for disease activity indices than for any of the individual measures. The 28-joint Disease Activity Score, Clinical Disease Activity Index, and Simplified Disease Activity Index performed similarly. Pain and physician's (PGA) and patient's global assessment (PtGA) of disease activity were the most responsive individual measures. Similar results were obtained for discriminative ability, with greatest ES for disease activity indices followed by pain, PGA, and PtGA. Pain was the only measure to demonstrate incremental validity beyond SDAI in predicting 3-month flare status. These results support the use of composite disease activity indices, patient-reported pain and disease activity, and physician-reported disease activity for measuring disease exacerbation or identifying flares of RA. Physical function, acute-phase response, and the auxiliary measures fatigue, participation, and emotional well-being performed poorl