S4ND: Single-Shot Single-Scale Lung Nodule Detection

The state of the art lung nodule detection studies rely on computationally expensive multi-stage frameworks to detect nodules from CT scans. To address this computational challenge and provide better performance, in this paper we propose S4ND, a new deep learning based method for lung nodule detection. Our approach uses a single feed forward pass of a single network for detection and provides better performance when compared to the current literature. The whole detection pipeline is designed as a single $3D$ Convolutional Neural Network (CNN) with dense connections, trained in an end-to-end manner. S4ND does not require any further post-processing or user guidance to refine detection results. Experimentally, we compared our network with the current state-of-the-art object detection network (SSD) in computer vision as well as the state-of-the-art published method for lung nodule detection (3D DCNN). We used publically available $888$ CT scans from LUNA challenge dataset and showed that the proposed method outperforms the current literature both in terms of efficiency and accuracy by achieving an average FROC-score of $0.897$. We also provide an in-depth analysis of our proposed network to shed light on the unclear paradigms of tiny object detection.Comment: Accepted for publication at MICCAI 2018 (21st International Conference on Medical Image Computing and Computer Assisted Intervention

High-Energy Astrophysics in the 2020s and Beyond

With each passing decade, we gain new appreciation for the dynamic, connected, and often violent nature of the Universe. This reality necessarily places the study of high-energy processes at the very heart of modern astrophysics. This White Paper illustrates the central role of high-energy astrophysics to some of the most pressing astrophysical problems of our time, the formation/evolution of galaxies, the origin of the heavy elements, star and planet formation, the emergence of life on exoplanets, and the search for new physics. We also highlight the new connections that are growing between astrophysicists and plasma physicists. We end with a discussion of the challenges that must be addressed to realize the potential of these connections, including the need for integrated planning across physics and astronomy programs in multiple agencies, and the need to foster the creativity and career aspirations of individual scientists in this era of large projects.Comment: Astro2020 White Paper submissio

Direct generation of a multi-transverse mode non-classical state of light

Quantum computation and communication protocols require quantum resources which are in the continuous variable regime squeezed and/or quadrature entangled optical modes. To perform more and more complex and robust protocols, one needs sources that can produce in a controlled way highly multimode quantum states of light. One possibility is to mix different single mode quantum resources. Another is to directly use a multimode device, either in the spatial or in the frequency domain. We present here the first experimental demonstration of a device capable of producing simultanuously several squeezed transverse modes of the same frequency and which is potentially scalable. We show that this device, which is an Optical Parametric Oscillator using a self-imaging cavity, produces a multimode quantum resource made of three squeezed transverse modes

Fast and Accurate Simulation of Multithreaded Sparse Linear Algebra Solvers

International audienceThe ever growing complexity and scale of parallel architectures imposes to rewrite classical monolithic HPC scientific applications and libraries as their portability and performance optimization only comes at a prohibitive cost. There is thus a recent and general trend in using instead a modular approach where numerical algorithms are written at a high level independently of the hardware architecture as Directed Acyclic Graphs (DAG) of tasks. A task-based runtime system then dynamically schedules the resulting DAG on the different computing resources, automatically taking care of data movement and taking into account the possible speed heterogeneity and variability. Evaluating the performance of such complex and dynamic systems is extremely challenging especially for irregular codes. In this article, we explain how we crafted a faithful simulation, both in terms of performance and memory usage, of the behavior of qr_mumps, a fully-featured sparse linear algebra library, on multi-core architectures. In our approach, the target high-end machines are calibrated only once to derive sound performance models. These models can then be used at will to quickly predict and study in a reproducible way the performance of such irregular and resource-demanding applications using solely a commodity laptop

Exploring the antimicrobial properties of dark-operating ceramic-based nanocomposite materials for the disinfection of indoor air

International audienceAs people spend more and more time inside, the quality of indoor air becomes crucial matter. This study explores the germicidal potential of two dark-operating germicidal composite materials designed to be applied for the indoor air disinfection under flow conditions. The first material, MnO 2 /AlPO 4 /γ-Al 2 O 3 beads, is a donor-acceptor interactive composite capable of creating hydroxyl radicals HO.. The second one is a ZnO/γ-Al 2 O 3 material with inter-cropped hexagons on its surface. To determine the antimicrobial efficiency of these materials in lifelike conditions, a pilot device was constructed that allows the test of the materials in dynamic conditions and agar diffusion inhibitory tests were also conducted. The results of the tests showed that the MnO 2 /AlPO 4 /γ-Al 2 O 3 material has a germicidal effect in static conditions whereas ZnO/γ-Al 2 O 3 does not. In dynamic conditions, the oxidizing MnO 2 / AlPO 4 /γ-Al 2 O 3 material is the most efficient when using low air speed whereas the ZnO/γ-Al 2 O 3 one becomes more efficient than the other materials when increasing the air linear speed. This ZnO/γ-Al 2 O 3 dark-operating germicidal material manifests the ability to proceed the mechanical destruction of bacterial cells. Actually, the antimicrobial efficiency of materials in dynamic conditions varies regarding the air speed through the materials and that static tests are not representative of the behavior of the material for air disinfection. Depending on the conditions, the best strategy to inactivate microorganisms changes and abrasive structures are a field that needs further exploration as they are in most of the conditions tested the best way to quickly decrease the number of microorganisms

Injectable Magnetic-Responsive Short-Peptide Supramolecular Hydrogels: Ex Vivo and In Vivo Evaluation

This study was supported by project FIS2017-85954-R funded by MCIN/AEI/10.13039/501100011033/FEDER "Una manera de hacer Europa", Spain, grants FIS PI20/0317 and ICI19/00024 (BIOCLEFT) (MINECO, Instituto de Salud Carlos III, Spain, cofinanced by FEDER funds, European Union), grant PE-0395-2019 (Consejeri ' a de Salud y Familias, Junta de Andalucia ', Spain), and project PPJIB2020.07 (Universidad de Granada, Spain). M.C.M.-T. acknowledges grant PRE2018-083773 funded by MCIN/AEI/10.13039/501100011033 and FSE "El FSE invierte en tu futuro", Spain. C.G.-V. acknowledges grant FPU17/00491 funded by MCIN/AEI/10.13039/501100011033 and FSE "El FSE invierte en tu futuro", Spain. P.K., D.M., and J.-C.S. acknowledge the French Agence Nationale de la Recherche, Project Future Investments UCA JEDI no. ANR-15-IDEX-01 (project RheoGels) for financial support. Funding for open access charge: Universidad de Granada/CBUA.The inclusion of magnetic nanoparticles (MNP) in a hydrogel matrix to produce magnetic hydrogels has broadened the scope of these materials in biomedical research. Embedded MNP offer the possibility to modulate the physical properties of the hydrogel remotely and on demand by applying an external magnetic field. Moreover, they enable permanent changes in the mechanical properties of the hydrogel, as well as alterations in the micro- and macroporosity of its threedimensional (3D) structure, with the associated potential to induce anisotropy. In this work, the behavior of biocompatible and biodegradable hydrogels made with Fmoc-diphenylalanine (Fmoc-FF) (Fmoc = fluorenylmethoxycarbonyl) and Fmoc−arginine−glycine− aspartic acid (Fmoc-RGD) short peptides to which MNP were incorporated was studied in detail with physicochemical, mechanical, and biological methods. The resulting hybrid hydrogels showed enhance mechanical properties and withstood injection without phase disruption. In mice, the hydrogels showed faster and improved self-healing properties compared to their nonmagnetic counterparts. Thanks to these superior physical properties and stability during culture, they can be used as 3D scaffolds for cell growth. Additionally, magnetic short-peptide hydrogels showed good biocompatibility and the absence of toxicity, which together with their enhanced mechanical stability and excellent injectability make them ideal biomaterials for in vivo biomedical applications with minimally invasive surgery. This study presents a new approach to improving the physical and mechanical properties of supramolecular hydrogels by incorporating MNP, which confer structural reinforcement and stability, remote actuation by magnetic fields, and better injectability. Our approach is a potential catalyst for expanding the biomedical applications of supramolecular short-peptide hydrogels.Instituto de Salud Carlos III FIS PI20/0317 ICI19/00024European CommissionFSE "El FSE invierte en tu futuro", SpainFrench National Research Agency (ANR) ANR-15-IDEX-01Universidad de Granada/CBUAFIS2017-85954-R MCIN/AEI/10.13039/501100011033/FEDER PE-0395-2019 PPJIB2020.07 PRE2018-083773 MCIN/AEI/10.13039/501100011033 FPU17/0049

Elemental Abundances in the Possible Type Ia Supernova Remnant G344.7-0.1

Recent studies on the Galactic supernova remnant (SNR) G344.7-0.1 have commonly claimed its origin to be a core-collapse supernova (SN) explosion, based on its highly asymmetric morphology and/or proximity to a star forming region. In this paper, however, we present an X-ray spectroscopic study of this SNR using Suzaku, which is supportive of a Type Ia origin. Strong K-shell emission from lowly ionized Fe has clearly been detected, and its origin is determined, for the first time, to be the Fe-rich SN ejecta. The abundance pattern is highly consistent with that expected for a somewhat-evolved Type Ia SNR. It is suggested, therefore, that the X-ray point-like source CXOU J170357.8-414302 located at the SNR's geometrical center is not associated with the SNR but is likely to be a foreground object. Our result further indicates that G344.7-0.1 is the first possible Type Ia SNR categorized as a member of the so-called "mixed-morphology" class. In addition, we have detected emission from He-like Al at ~1.6 keV, the first clear detection of this element in the spectrum of an extended X-ray source. The possible enhancement of the Al/Mg abundance ratio from the solar value suggests that the ambient interstellar medium has a relatively high metallicity (not less than 10% of the solar value), if this SNR has indeed a Type Ia origin. We also report marginal detection of Cr and Mn, although the measured fluxes have large statistical and systematic uncertainties.Comment: ApJ in pres

Issues in joint SZ and optical cluster finding

We apply simple optical and SZ cluster finders to mock galaxy catalogues and SZ flux maps created from dark matter halos in a (1 Gpc/h)^3 dark matter simulation, at redshifts 0.5 and 0.9. At each redshift, the two catalogues are then combined to assess how well they can improve each other, and compared to several variants of catalogues made using SZ flux and galaxy information simultaneously. We use several different criteria to compare the catalogues, and illustrate some of the tradeoffs which arise in tuning the galaxy cluster finders with respect to these criteria. We detail many of the resulting improvements and issues which arise in comparing and combining these two types of data sets.Comment: 14 pages, added information thanks to helpful suggestions from refere