Wiener filter reloaded: fast signal reconstruction without preconditioning

We present a high performance solution to the Wiener filtering problem via a formulation that is dual to the recently developed messenger technique. This new dual messenger algorithm, like its predecessor, efficiently calculates the Wiener filter solution of large and complex data sets without preconditioning and can account for inhomogeneous noise distributions and arbitrary mask geometries. We demonstrate the capabilities of this scheme in signal reconstruction by applying it on a simulated cosmic microwave background (CMB) temperature data set. The performance of this new method is compared to that of the standard messenger algorithm and the preconditioned conjugate gradient (PCG) approach, using a series of well-known convergence diagnostics and their processing times, for the particular problem under consideration. This variant of the messenger algorithm matches the performance of the PCG method in terms of the effectiveness of reconstruction of the input angular power spectrum and converges smoothly to the final solution. The dual messenger algorithm outperforms the standard messenger and PCG methods in terms of execution time, as it runs to completion around 2 and 3-4 times faster than the respective methods, for the specific problem considered.Comment: 13 pages, 10 figures. Accepted for publication in MNRAS main journa

Complete lung agenesis caused by complex genomic rearrangements with neo-TAD formation at the SHH locus

During human organogenesis, lung development is a timely and tightly regulated developmental process under the control of a large number of signaling molecules. Understanding how genetic variants can disturb normal lung development causing different lung malformations is a major goal for dissecting molecular mechanisms during embryogenesis. Here, through exome sequencing (ES), array CGH, genome sequencing (GS) and Hi-C, we aimed at elucidating the molecular basis of bilateral isolated lung agenesis in three fetuses born to a non-consanguineous family. We detected a complex genomic rearrangement containing duplicated, triplicated and deleted fragments involving the SHH locus in fetuses presenting complete agenesis of both lungs and near-complete agenesis of the trachea, diagnosed by ultrasound screening and confirmed at autopsy following termination. The rearrangement did not include SHH itself, but several regulatory elements for lung development, such as MACS1, a major SHH lung enhancer, and the neighboring genes MNX1 and NOM1. The rearrangement incorporated parts of two topologically associating domains (TADs) including their boundaries. Hi-C of cells from one of the affected fetuses showed the formation of two novel TADs each containing SHH enhancers and the MNX1 and NOM1 genes. Hi-C together with GS indicate that the new 3D conformation is likely causative for this condition by an inappropriate activation of MNX1 included in the neo-TADs by MACS1 enhancer, further highlighting the importance of the 3D chromatin conformation in human disease

The Young Supernova Experiment: Survey Goals, Overview, and Operations

Time domain science has undergone a revolution over the past decade, with tens of thousands of new supernovae (SNe) discovered each year. However, several observational domains, including SNe within days or hours of explosion and faint, red transients, are just beginning to be explored. Here, we present the Young Supernova Experiment (YSE), a novel optical time-domain survey on the Pan-STARRS telescopes. Our survey is designed to obtain well-sampled $griz$ light curves for thousands of transient events up to $z \approx 0.2$. This large sample of transients with 4-band light curves will lay the foundation for the Vera C. Rubin Observatory and the Nancy Grace Roman Space Telescope, providing a critical training set in similar filters and a well-calibrated low-redshift anchor of cosmologically useful SNe Ia to benefit dark energy science. As the name suggests, YSE complements and extends other ongoing time-domain surveys by discovering fast-rising SNe within a few hours to days of explosion. YSE is the only current four-band time-domain survey and is able to discover transients as faint $\sim$21.5 mag in $gri$ and $\sim$20.5 mag in $z$, depths that allow us to probe the earliest epochs of stellar explosions. YSE is currently observing approximately 750 square degrees of sky every three days and we plan to increase the area to 1500 square degrees in the near future. When operating at full capacity, survey simulations show that YSE will find $\sim$5000 new SNe per year and at least two SNe within three days of explosion per month. To date, YSE has discovered or observed 8.3% of the transient candidates reported to the International Astronomical Union in 2020. We present an overview of YSE, including science goals, survey characteristics and a summary of our transient discoveries to date.Comment: ApJ, in press; more information at https://yse.ucsc.edu

The quijote simulations

The Quijote simulations are a set of 44,100 full N-body simulations spanning more than 7000 cosmological models in the hyperplane. At a single redshift, the simulations contain more than 8.5 trillion particles over a combined volume of 44,100 each simulation follows the evolution of 2563, 5123, or 10243 particles in a box of 1 h -1 Gpc length. Billions of dark matter halos and cosmic voids have been identified in the simulations, whose runs required more than 35 million core hours. The Quijote simulations have been designed for two main purposes: (1) to quantify the information content on cosmological observables and (2) to provide enough data to train machine-learning algorithms. In this paper, we describe the simulations and show a few of their applications. We also release the petabyte of data generated, comprising hundreds of thousands of simulation snapshots at multiple redshifts; halo and void catalogs; and millions of summary statistics, such as power spectra, bispectra, correlation functions, marked power spectra, and estimated probability density functions

Scramjet flow visualization using background oriented schlieren in hypersonic impulse facilities

The Background Oriented Schlieren (BOS) technique is a method that has been developed recently for easily and inexpensively visualizing density gradient variations in compressible flows. In this paper, the application of this technique in the T4 free-piston reflected shock tunnel is presented. The BOS technique was used during three test campaigns to qualitatively visualize the flow over scramjet models and components of scramjets. The results demonstrate that a simple optical arrangement, that does not include high quality windows in the test section and model, can be used to detect the locations of shock waves, expansion fans and shear layers. At present, the resolution and quality of the images is not as high as can be achieved using conventional schlieren techniques

Wiener filtering and pure E/B\mathcal {E}/\mathcal {B} decomposition of CMB maps with anisotropic correlated noise

International audienceWe present an augmented version of our dual messenger algorithm for spin field reconstruction on the sphere, while accounting for highly non-trivial and realistic noise models such as modulated correlated noise. We also describe an optimization method for the estimation of noise covariance from Monte Carlo simulations. Using simulated Planck polarized cosmic microwave background (CMB) maps as a showcase, we demonstrate the capabilities of the algorithm in reconstructing pure |$\mathcal {E}$| and |$\mathcal {B}$| maps, guaranteed to be free from ambiguous modes resulting from the leakage or coupling issue that plagues conventional methods of |$\mathcal {E}/\mathcal {B}$| separation. Due to its high speed execution, coupled with lenient memory requirements, the algorithm can be optimized in exact global Bayesian analyses of state-of-the-art CMB data for a statistically optimal separation of pure |$\mathcal {E}$| and |$\mathcal {B}$| modes. Our algorithm, therefore, has a potentially key role in the data analysis of high-resolution and high-sensitivity CMB data, especially with the range of upcoming CMB experiments tailored for the detection of the elusive primordial |$\mathcal {B}$|-mode signal

Optimal and fast E/B\mathcal {E}/\mathcal {B} separation with a dual messenger field

International audienceWe adapt our recently proposed dual messenger algorithm for spin field reconstruction and showcase its efficiency and effectiveness in Wiener filtering polarized cosmic microwave background (CMB) maps. Unlike conventional preconditioned conjugate gradient (PCG) solvers, our preconditioner-free technique can deal with high-resolution joint temperature and polarization maps with inhomogeneous noise distributions and arbitrary mask geometries with relative ease. Various convergence diagnostics illustrate the high quality of the dual messenger reconstruction. In contrast, the PCG implementation fails to converge to a reasonable solution for the specific problem considered. The implementation of the dual messenger method is straightforward and guarantees numerical stability and convergence. We show how the algorithm can be modified to generate fluctuation maps, which, combined with the Wiener filter solution, yield unbiased constrained signal realizations, consistent with observed data. This algorithm presents a pathway to exact global analyses of high-resolution and high-sensitivity CMB data for a statistically optimal separation of $$\mathcal {E}$$ and $$\mathcal {B}$$ modes. It is therefore relevant for current and next-generation CMB experiments, in the quest for the elusive primordial $$\mathcal {B}$$-mode signal

[Integrating HPV testing for primary screening?]

International audienceCervical cancer, the second most common cancer in young women in France, is still today imperfectly screened even with the advent of primary prevention for this cancer in the form of prophylactic HPV vaccination. Indeed, the cervical Pap smear and its cytologic analysis, both operator and reader dependent, have limited sensitivities requiring repeated samplings and above all, producing a high rate of falsely negative tests. Although most cancers occur in women who are either not or insufficiently screened, the problem with cervical smears is the fact that cancers are also often diagnosed in young women having follow-ups in accordance with professional guidelines. The absence of an organized screening in France results in an inadequate female population coverage. Nowadays, it is unanimously recognized that high-risk papillomaviruses (HR HPV) represent the only independent risk factor for cervical cancer and that there cannot be any disease without this virus. It is therefore this strong association between a viral agent and the cervical cancer which opened the door firstly, to the notion of prophylactic vaccination and secondly, to the integration of HR HPV testing in the screening for precancerous lesions. Molecular biological techniques based on the HR HPV genome detection within the female genital tract have shown a very high sensitivity without any inter and intraobserver variability and an excellent negative predictive value. Their integration in the primary screening for cervical cancer would improve the relevance of the latter and would suit the need for a wider population coverage and even for an organized screening thanks to the possibility for self-sampling. The specificity of these tests is inferior to that of the cervical smear, but the management of the falsely positive HPV tests has proved to be efficient by sorting residual cells obtained from liquid-based cytology. What is urgent in France is the need for an organized screening programme in order to improve population coverage and, this does not go against neither a vaccination promotion nor the integration of new technologies. Moreover, the last three randomized trials published in October 2007 have shown that it was quite safely possible to extend the time interval between two consecutive viral testing and thus improving the cost-effectiveness of cervical cancer screening. The aim of this work was to analyze publications on the subject in order to conclude, according to proof levels obtained by different studies, on its usefulness in the secondary prevention of cervical cancer

[Vacuum extractors: description, mechanics, indications and contra-indications]

International audienceThe vacuum extractor, as opposed to other instruments, does not increase the fetal head diameter for vaginal delivery. Introduced half a century ago, this device is today widely used in many countries probably because of a learning-curve which is acquired quicker than for the forceps. Major benefits obtained are the flexion of the fetal head provided that the cup is correctly placed, and the compulsory rotation induced that is most useful in the conversion of occiput posterior or transverse to anterior positions. The limitations reside in the need for maternal effort at expulsion and in the fact that it is unsuitable for face presentations. Moreover, like other instruments, the vacuum extractor can be harmful and even dangerous to the mother and her fetus. Therefore, its indications and contra-indications must be respected, and its operative use mastered with as much precision as for the forceps