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A letter to the editor is presented regarding a report of two sisters that carry identical compound heterozygous mutations in IL36RN, an encoding interleukin 36 receptor antagonist (IL-36Ra).

Decoherence of the 795 nm 3H6 to 3H4 transition in l%Tm3+:Tm3+:Y3Ga5O12 (Tm:YGG) is studied at temperatures as low as 1.2 K. The temperature, magnetic field, frequency, and time scale (spectral diffusion) dependence of the optical coherence lifetime is measured. Our results show that the coherence lifetime is impacted less by spectral diffusion than other known thulium-doped materials. Photon echo excitation and spectral hole burning methods reveal uniform decoherence properties and the possibility to produce full transparency for persistent spectral holes across the entire 56 GHz inhomogeneous bandwidth of the optical transition. Temperature-dependent decoherence is well described by elastic Raman scattering of phonons with an additional weaker component that may arise from a low density of glass-like dynamic disorder modes (two-level systems). Analysis of the observed behavior suggests that an optical coherence lifetime approaching 1 ms may be possible in this system at temperatures below 1 K for crystals grown with optimized properties. Overall, we find that Tm: YGG has superior decoherence properties compared to other Tm-doped crystals and is a promising candidate for applications that rely on long coherence lifetimes, such as optical quantum memories and photonic signal processing. [ABSTRACT FROM AUTHOR]

We investigate the relevant spectroscopic properties of the 795 nm 3H6↔3H4 transition in 1% Tm3+: Y3Ga5O12 at temperatures as low as 1.2 K for optical quantum memories based on persistent spectral tailoring of narrow absorption features. Our measurements reveal that this transition has uniform coherence properties over a 56 GHz bandwidth, and a simple hyperfine structure split by ±44 MHz/T with lifetimes of up to hours. Furthermore, we find a 3F4 population lifetime of 64 ms--one of the longest lifetimes observed for an electronic level in a solid-and an exceptionally long coherence lifetime of 490 αs-the longest ever observed for optical transitions of Tm3+ ions in a crystal. Our results suggest that this material allows realizing broadband quantum memories that enable spectrally multiplexed quantum repeaters. [ABSTRACT FROM AUTHOR]

Aims: To highlight the long-lasting benefit of 2-0 Prolene brow suspension for congenital ptosis. Methods: Retrospective case review of 38 paediatric cases at two centres in the United Kingdom. Results: Six cases continue to have a successful functional and cosmetic result ranging from 6 to 10 years. Conclusions: Brow suspension with 2-0 Prolene can be long-lasting in some patients. [ABSTRACT FROM AUTHOR]

Researching sensitive topics, such as the treatment of men with intellectual disabilities and sexually abusive behaviour, present a number of ethical issues for researchers. This paper describes our experiences in working with Multi-Centre Research Ethics Committees on a research proposal designed to assess the efficacy of cognitive behaviour therapy for men with intellectual disabilities who are at risk of sexual offending. After submitting to three Multi-Centre Research Ethics Committees and spending a year trying to get ethical approval, we questioned whether: * the issue of study design should be part of the Multi-Centre Research Ethics Committees remit;* Multi-Centre Research Ethics Committees were sufficiently responsive to concerns raised by researchers;* Multi-Centre Research Ethics Committees always understood the research; and* the Central Office for Research Ethics Committees should disallow re-submission after rejection by two Multi-Centre Research Ethics Committees ('two strikes and you're out'). [ABSTRACT FROM AUTHOR]

Concomitant ligation of antigen receptors with Fc-receptors negatively signals B cells. Antibodies to the Fc portion of IgG prevent this negative Fc-signalling, provided that these antibodies do not emit Fc signals. Prevention of Fc signals leads to augmented antibody responses to self and foreign antigens, and reduces the requirement for T cells by 10- to 100-fold in T cell-dependent antibody responses. In HLISA assays, peptides from conserved portions of the glycoproteins, HIV-1 gp120 or gp41 from HIV-1 and HIV-2 bind to the Fc portion of IgG, but do not bind the F(ab')2 portion of IgG. HIV-derived peptides. which bind to the Fc portion of IgG. augment the antibody-forming cell response to single-stranded (ss)DNA, The spontaneous response to ssDNA using spleen cells from young mice, and the response in the presence of exogenous DNA using spleen cells from old mice, are augmented to the greatest extent. These results demonstrate that HIV peptides bind to the Fc portion of IgG and augment immune responses to DNA; they suggest the possibility that blockade of the Fc portion of IgG antibodies is associated with a reduction in Fc-mediated regulation of anti-self responses. Blockade of regulatory Fc-signalling may account for increased circulating immunoglobulins and autoantibodies in clinical AIDS. [ABSTRACT FROM AUTHOR]

The performance of pooled superannuation funds is analysed within a framework that recognises that risk management or 'market timing' is an important aspect of the fund manager's decision-making. Two broad appraoches to the issue of 'market timing' are adopted: first, the performance evaluation model developed by Henriksson and Merton [1981] which allows for return differentials to arise from both security selection and market timing; and second, the recursive residuals methodology of Brown, Durbin and Evans [1975] which identifies points in chronological time when the risks of the funds underwent a change. The results indicate that only 5 out of 16 funds had significant shifts in their risk over the period of the study, all of which occurred in late 1986 to early 1987. It follows that the usual Jensen measure of performance is inappropriate for these funds since one component of their performance is due to market timing activities. The return performance of these market timing activities is significantly negative for 15 to 16 funds indicating that their timing ability is perverse. To some extent this is an artifact of the market crash of October 1987 and that all funds had a positive exposure to equities. However, due to their asset allocation policies all funds are assigned significantly positive security selection performance. [ABSTRACT FROM AUTHOR]

This paper contributes to the empirical literature which documents the existence of a positive association between unexpected earnings and/or dividend announcements and abnormal returns to equity. The paper addresses some of the methodological limitations evident in the literature. In particular, one methodological difficulty encountered by previous studies is that since earnings and dividend announcements are usually made contemporaneously it is difficult to assess the marginal effect of either announcement on security returns. This problem is dealt with by constructing portfolios of securities which are randomized with respect to unexpected earnings (dividends), but which are systematically ranked on unexpected dividends (earnings). The results indicate that unexpected earnings announcements have a significant marginal impact on abnormal returns. In addition, there is evidence of an impact of unexpected dividends on returns, but it is weaker than unexpected earnings. [ABSTRACT FROM AUTHOR]

Since the early 1960s, the mean-variance Capital Asset Pricing Model (CAPM) has been a dominant paradigm in modern finance. Recently, the accumulation of anomalous evidence, and a realisation that empirical tests of the model are tautologically related to the efficiency of the market index, have pushed that paradigm to a point of crisis. This paper reviews alternative asset pricing models which coexisted with the CAPM and may provide plausible substitutes. The major distinguishing feature of these models is that they predict multiple risk factors and, with the exception of the Arbitrage Pricing Theory (APT), are extensions of the CAPM. [ABSTRACT FROM AUTHOR]