Breaking the Contrast Limit in Single-Pass Fabry-Pérot Spectrometers

The development of high-resolution Fabry-Pérot interferometers has enabled a wide range of scientific and technological advances—ranging from the characterization of material properties to the more fundamental studies of quasi particles in condensed matter. Spectral contrast is key to measuring weak signals and can reach a 103 peak-to-background ratio in a single-pass assembly.At its heart, this limit is a consequence of an unbalanced field amplitude across multiple interfering paths, with an ensuing reduced fringe visibility. Using a high-resolution, high-throughput virtually imaged phased array spectrometer, we demonstrate an intensity-equalization method to achieve an unprecedented 1000-fold increase in spectral contrast in a single-stage, single-pass configuration. To validate the system, we obtain the Brillouin spectrum of water at high scattering concentrations where, unlike with the standard scheme, the inelastic peaks are highly resolved. Our method brings the interferometer close to its ultimate limits and allows rapid high-resolution spectral analysis in a wide range of fields, including Brillouin spectroscopy, mechanical imaging, and molecular fingerprinting

Phase- and Stage-Related Proportions of T Cells Bearing the Transcription Factor FOXP3 Infiltrate Primary Melanoma

Although tumor-infiltrating lymphocytes (TILs) of primary cutaneous melanoma (PCM) include cytolytic T cells able to exert anti-PCM immunity, progression of PCM most frequently occurs, raising the hypothesis that the PCM microenvironment may also exert suppressive forces, for example, possibly developed by regulatory T (TREG) lymphocytes. The aim of this study was to investigate whether TILs of PCMs include lymphocytes bearing the transcription factor forkhead box protein P3 (FOXP3), which is the TREG lineage specification molecule in mice, and is debated to have a similar role in humans. Fourteen patients with PCM were selected, of which four had radial growth phase (RGP) stage I melanoma, five had vertical growth phase (VGP) stage I melanoma, and five had VGP stage III–IV melanoma. Formalin-fixed, paraffin-embedded sections were utilized for immunohistochemical single and double stainings. TILs of PCMs included FOXP3-bearing lymphocytes, which predominantly were CD20- and CD8-negative, but CD3-, CD4-, and CD25-positive, thus consistent with the standard immunophenotypical characteristics of “natural” TREG cells. Further, the proportions of FOXP3-bearing lymphocytes were higher in vertical than in RGP (P=0.001), as well as in late than in early melanoma stages (P<0.001). Should these FOXP3-bearing lymphocytes actually exert regulatory capabilities within the PCM microenvironment, they may suppress “in vivo” the local anti-PCM immune response, thus favoring melanoma progression

The association between insight and depressive symptoms in schizophrenia: Undirected and Bayesian network analyses

Background. Greater levels of insight may be linked with depressive symptoms among patients with schizophrenia, however, it would be useful to characterize this association at symptom-level, in order to inform research on interventions. Methods. Data on depressive symptoms (Calgary Depression Scale for Schizophrenia) and insight (G12 item from the Positive and Negative Syndrome Scale) were obtained from 921 community-dwelling, clinically-stable individuals with a DSM-IV diagnosis of schizophrenia, recruited in a nationwide multicenter study. Network analysis was used to explore the most relevant connections between insight and depressive symptoms, including potential confounders in the model (neurocognitive and social-cognitive functioning, positive, negative and disorganization symptoms, extrapyramidal symptoms, hostility, internalized stigma, and perceived discrimination). Bayesian network analysis was used to estimate a directed acyclic graph (DAG) while investigating the most likely direction of the putative causal association between insight and depression. Results. After adjusting for confounders, better levels of insight were associated with greater self-depreciation, pathological guilt, morning depression and suicidal ideation. No difference in global network structure was detected for socioeconomic status, service engagement or illness severity. The DAG confirmed the presence of an association between greater insight and self-depreciation, suggesting the more probable causal direction was from insight to depressive symptoms. Conclusions. In schizophrenia, better levels of insight may cause self-depreciation and, possibly, other depressive symptoms. Person-centered and narrative psychotherapeutic approaches may be particularly fit to improve patient insight without dampening self-esteem