Underdetermined instantaneous audio source separation via local Gaussian modeling

International audienceUnderdetermined source separation is often carried out by modeling time-frequency source coefficients via a fixed sparse prior. This approach fails when the number of active sources in one time-frequency bin is larger than the number of channels or when active sources lie on both sides of an inactive source. In this article, we partially address these issues by modeling time-frequency source coefficients via Gaussian priors with free variances. We study the resulting maximum likelihood criterion and derive a fast non-iterative optimization algorithm that finds the global minimum. We show that this algorithm outperforms state-of-the- art approaches over stereo instantaneous speech mixtures

Magnetic fields in the early universe in the string approach to MHD

There is a reformulation of magnetohydrodynamics in which the fundamental dynamical quantities are the positions and velocities of the lines of magnetic flux in the plasma, which turn out to obey equations of motion very much like ideal strings. We use this approach to study the evolution of a primordial magnetic field generated during the radiation-dominated era in the early Universe. Causality dictates that the field lines form a tangled random network, and the string-like equations of motion, plus the assumption of perfect reconnection, inevitably lead to a self-similar solution for the magnetic field power spectrum. We present the predicted form of the power spectrum, and discuss insights gained from the string approximation, in particular the implications for the existence or not of an inverse cascade.Comment: 12 pages, 2 figure

Validity of the independence assumption for the separation of instantaneous and convolutive mixtures of speech and music sources

International audienceIn this paper, we study the validity of the assumption that speech source signals exhibit lower dependency and therefore better separability with Independent Component Analysis algorithms than music sources. In particular, we investigate some dependency measures in the temporal and the time-frequency domains, resp. in the framework of instantaneous and convolutive mixtures. Moreover, we test several ICA methods, based on the above dependency measures, on the same source signals. We experimentally show that speech and music sources tend to have the same mean behaviour for excerpt durations above 20~ms, but music signals provide more spread dependency measures and SIR values. Lastly, we experimentally show that Gaussian nonstationary mutual information is better suited to audio signals than mutual information

Parity-Violating Interaction Effects I: the Longitudinal Asymmetry in pp Elastic Scattering

The proton-proton parity-violating longitudinal asymmetry is calculated in the lab-energy range 0--350 MeV, using a number of different, latest-generation strong-interaction potentials--Argonne V18, Bonn-2000, and Nijmegen-I--in combination with a weak-interaction potential consisting of rho- and omega-meson exchanges--the model known as DDH. The complete scattering problem in the presence of parity-conserving, including Coulomb, and parity-violating potentials is solved in both configuration- and momentum-space. The predicted parity-violating asymmetries are found to be only weakly dependent upon the input strong-interaction potential adopted in the calculation. Values for the rho- and omega-meson weak coupling constants $h^{pp}_\rho$ and $h^{pp}_\omega$ are determined by reproducing the measured asymmetries at 13.6 MeV, 45 MeV, and 221 MeV.Comment: 24 pages, 8 figures, submitted to Physical Review

Neoadjuvant pazopanib and molecular analysis of tissue response in renal cell carcinoma

BACKGROUND. Surgery remains the frontline therapy for patients with localized clear cell renal cell carcinoma (ccRCC); however, 20%–40% recur. Angiogenesis inhibitors have improved survival in metastatic patients and may result in responses in the neoadjuvant setting. The impact of these agents on the tumor genetic heterogeneity or the immune milieu is largely unknown. This phase II study was designed to evaluate safety, response, and effect on tumor tissue of neoadjuvant pazopanib. METHODS. ccRCC patients with localized disease received pazopanib (800 mg daily; median 8 weeks), followed by nephrectomy. Five tumors were examined for mutations by whole exome sequencing from samples collected before therapy and at nephrectomy. These samples underwent RNA sequencing; 17 samples were available for posttreatment assessment. RESULTS. Twenty-one patients were enrolled. The overall response rate was 8 of 21 (38%). No patients with progressive disease. At 1-year, response-free survival and overall survival was 83% and 89%, respectively. The most frequent grade 3 toxicity was hypertension (33%, 7 of 21). Sequencing revealed strong concordance between pre- and posttreatment samples within individual tumors, suggesting tumors harbor stable core profiles. However, a reduction in private mutations followed treatment, suggesting a selective process favoring enrichment of driver mutations. CONCLUSION. Neoadjuvant pazopanib is safe and active in ccRCC. Future genomic analyses may enable the segregation of driver and passenger mutations. Furthermore, tumor infiltrating immune cells persist during therapy, suggesting that pazopanib can be combined with immune checkpoint inhibitors without dampening the immune response. FUNDING. Support was provided by Novartis and GlaxoSmithKline as part of an investigator-initiated study

An Uncertain Dominion: Irish Psychiatry, Methadone, and the Treatment of Opiate Abuse

This paper investigates some productive ambiguities around the medical administration of methadone in the Republic of Ireland. The tensions surrounding methadone maintenance therapy (MMT) are outlined, as well as the sociohistorical context in which a serious heroin addiction problem in Ireland developed. Irish psychiatry intervened in this situation, during a time of institutional change, debates concerning the nature of addiction, moral panics concerning heroin addiction in Irish society and the recent boom in the Irish economy, known popularly as the Celtic Tiger. A particular history of this sort illuminates how technologies like MMT become cosmopolitan, settling into, while changing, local contexts

Low-lying T=0 states in the odd-odd N=Z nucleus ⁶² Ga

AbstractNew, low-lying levels in the odd–odd, N=Z nucleus 62Ga have been identified using a sensitive technique, where in-beam γ rays from short-lived nuclei are tagged with β decays following recoil mass identification. A comparison of the results with shell-model and IBM-4 calculations demonstrates good agreement between theory and experiment, with the majority of predicted low-lying, low-spin T=0 states now identified. There is a dramatic change in the level density at low excitation energies for the N=Z nucleus 62Ga when compared with neighbouring odd–odd Ga isotopes where, in contrast, the low-lying level structure is dominated by configurations with T=1 pairing interactions between excess neutrons. This illustrates the distinctively different aspects of nuclear structure exhibited by nuclei with N=Z

Evaluating the efficacy of a priming dose of cyclophosphamide prior to pembrolizumab to treat metastatic triple negative breast cancer

PurposeTriple negative breast cancer (TNBC) is characterized by the presence of immune cells in the tumor microenvironment, however, the response to single-agent immune checkpoint inhibitor (ICI) therapy is modest. Preclinical models have demonstrated that intratumoral regulatory T cells (Tregs) dampen the antitumor response to ICI. We performed a single-arm phase II trial to evaluate the efficacy of a single low dose of cyclophosphamide (Cy) to deplete Tregs administered before initiating pembrolizumab.Patients and methods40 patients with pretreated metastatic TNBC were enrolled. The primary endpoints were progression-free survival (PFS) and change in peripheral blood Tregs after Cy. Secondary endpoints included overall response rate (ORR), duration of response, overall survival, treatment-related adverse events (AEs), and correlative evaluations.ResultsMedian PFS was 1.8 months, and the ORR was 21%. Tregs were not significantly decreased after Cy prior to ICI (−3.3%, p=0.19), and increased significantly after the first cycle of therapy (+21% between cycles 1 and 2, p=0.005). Immune-related AEs were similar to historical pembrolizumab monotherapy, and were associated with response to therapy (p=0.02). Patients with pretreatment tumors harboring increased expression of B cell metagene signatures and increased circulating B cell receptor repertoire diversity were associated with clinical response and immune-related toxicity (IRT).ConclusionsAmong patients with heavily pretreated TNBC, Cy prior to pembrolizumab did not significantly deplete Tregs, and in those with decreased numbers there was rapid recovery following therapy. Increased B cell gene expression in baseline samples was associated with clinical response and IRT

Repeatability and reproducibility of the measurement of prepreg tack following ASTM D8336: Results of a round-robin study

This study reports the findings from a round robin test exercise investigating ASTM D8336, a method for the measurement of tack of prepregs applicable to automated material placement technologies. Twelve participants tested two prepreg materials in a core study of three temperature and deposition/peel rate combinations, and five participants conducted an extended study based on a test matrix of four temperatures and four rates. In the core study, the repeatability coefficient of variation of obtained tack values ranged from 6.06 % to 15.08 %, while the reproducibility coefficient of variation ranged from 12.37 % to 32.37 %. The probable dominant causes for the observed variability are the limited accuracy of control and measurement of specimen temperature, of compaction force, and of humidity. Using time-temperature superposition, tack mastercurves were constructed from the extended study, identifying values of peak tack, the rate at peak tack and the width of the tack mastercurve, as well as the 95 % confidence and prediction bands. Across all materials and participants, 93.3 % of the repeats from the core study lay within the 95 % prediction bands, supporting the view 2 that a mastercurve provides a greater degree of useful information at a comparable effort for data acquisition

RANTES/CCL5 and risk for coronary events: Results from the MONICA/KORA Augsburg case-cohort, Athero-express and CARDIoGRAM studies

Background: The chemokine RANTES (regulated on activation, normal T-cell expressed and secreted)/CCL5 is involved in the pathogenesis of cardiovascular disease in mice, whereas less is known in humans. We hypothesised that its relevance for atherosclerosis should be reflected by associations between CCL5 gene variants, RANTES serum concentrations and protein levels in atherosclerotic plaques and risk for coronary events. Methods and Findings: We conducted a case-cohort study within the population-based MONICA/KORA Augsburg studies. Baseline RANTES serum levels were measured in 363 individuals with incident coronary events and 1,908 non-cases (mean follow-up: 10.2±