18 results on '"H. Benhabiles"'
Search Results
2. γ -ray emission in α -particle interactions with C, Mg, Si, and Fe at Eα=50–90 MeV
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H. Benhabiles, C. Hamadache, I. Deloncle, A. Gostojic, R. Mezhoud, I. Bourgaoub, Andrea Denker, Fairouz Hammache, Vincent Tatischeff, Jürgen Bundesmann, Jörg Röhrich, Jürgen Kiener, J. Peyré, and A. Coc
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Nuclear reaction ,Physics ,Solar flare ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Center (category theory) ,7. Clean energy ,01 natural sciences ,Base (group theory) ,Excited state ,0103 physical sciences ,Production (computer science) ,Emission spectrum ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Energy (signal processing) - Abstract
Nuclear deexcitation lines are regularly observed in the $\ensuremath{\gamma}$-ray emission spectra of strong solar flares. The most prominent lines are produced by interactions of protons and $\ensuremath{\alpha}$ particles, accelerated up to hundreds of MeV, with abundant nuclei of the solar atmosphere. Analysis and interpretation of these lines, which carry valuable information on the solar flare properties, need cross-section data for the $\ensuremath{\gamma}$-ray line emission in these interactions for a wide particle energy range. To this purpose, we measured the $\ensuremath{\gamma}$-ray emission in interactions of $\ensuremath{\alpha}$-particle beams of ${E}_{\ensuremath{\alpha}}=50\text{--}90$ MeV with target foils of C, Mg, Si, and Fe at the center for proton therapy of the Helmholtz-Zentrum Berlin. Setups of three high-purity Ge detectors and one $\mathrm{La}{\mathrm{Br}}_{3}$:Ce detector have been employed to detect the $\ensuremath{\gamma}$ rays in two experiment campaigns. Relatively large distances of the detectors from the target and pulsed beams with sub-ns-wide pulses allowed the separation of beam-induced prompt $\ensuremath{\gamma}$-ray emission from the targets from other $\ensuremath{\gamma}$ rays and neutron-induced background. $\ensuremath{\gamma}$-ray production cross sections for about 60 deexcitation lines from excited target nuclei or reaction products have been determined. For the strongest deexcitation lines from the major target isotopes, $^{12}\mathrm{C}$, $^{24}\mathrm{Mg}$, $^{28}\mathrm{Si}$, $^{56}\mathrm{Fe}$, there are now measured cross-section data from reaction threshold to ${E}_{\ensuremath{\alpha}}=90$ MeV that can be directly used for astrophysical applications like solar flares. Comparison of the results with a cross-section compilation for strong $\ensuremath{\gamma}$-ray lines in solar flare emissions and the predictions of the talys nuclear reaction code were done. They underline the importance of cross-section determinations at accelerator laboratories for the establishment of an accurate cross-section data base in a wide projectile energy range.
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- 2021
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3. Measurement and analysis of nuclear γ -ray production cross sections in proton interactions with Mg, Si, and Fe nuclei abundant in astrophysical sites over the incident energy range E=30–66 MeV
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S. P. Noncolela, P. Papka, J. Kiener, J. L. Conradie, A. Belhout, D. Moussa, S. Damache, W. Yahia-Chérif, J. L. Easton, E. A. Lawrie, Vincent Tatischeff, A. Chafa, J. J. Lawrie, Dinesh Negi, T. Lamula, S. N. T. Majola, N. de Sereville, F. Hammache, J. Ndayishimye, M. Wiedeking, M. Debabi, N. A. Khumalo, C. Hamadache, T. D. Bucher, J.F. Sharpey-Schafer, B. V. Kheswa, O. Shirinda, H. Benhabiles-Mezhoud, S. M. Wyngaardt, I. Deloncle, Peter B. Jones, and S. Ouichaoui
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Nuclear reaction ,Physics ,Range (particle radiation) ,Proton ,010308 nuclear & particles physics ,Scattering ,Cyclotron ,01 natural sciences ,law.invention ,Semiconductor detector ,Nuclear physics ,law ,0103 physical sciences ,Nuclear Experiment ,Nucleon ,010303 astronomy & astrophysics ,Excitation - Abstract
Gamma-ray production cross section excitation functions have been measured for $30$, $42$, $54$ and $66$ MeV proton beams accelerated onto targets of astrophysical interest, $^{nat}$C, C + O (Mylar), $^{nat}$Mg, $^{nat}$Si and $^{56}$Fe, at the Sector Separated Cyclotron (SSC) of iThemba LABS (near Cape Town, South Africa). The AFRODITE array equipped with 8 Compton suppressed HPGe clover detectors was used to record $\gamma$-ray data. For known, intense $\gamma$-ray lines the previously reported experimental data measured up to $E_{p}\simeq$ $25$ MeV at the Washington and Orsay tandem accelerators were extended to higher proton energies. Our experimental data for the last 3 targets are reported here and discussed with respect to previous data and the Murphy \textit{et al.} compilation [ApJS 183, 142 (2009)], as well as to predictions of the nuclear reaction code TALYS. The overall agreement between theory and experiment obtained in first-approach calculations using default input parameters of TALYS has been appreciably improved by using modified optical model potential (OMP), deformation, and level density parameters. The OMP parameters have been extracted from theoretical fits to available experimental elastic/inelastic nucleon scattering angular distribution data by means of the coupled-channels reaction code OPTMAN. Experimental data for several new $\gamma$-ray lines are also reported and discussed. The astrophysical implications of our results are emphasised.
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- 2020
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4. Gamma ray emission in alpha particle reactions with C, Mg, Si, Fe
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Jörg Röhrich, H. Benhabiles, Andrea Denker, I. Deloncle, Jürgen Bundesmann, J. Kiener, R. Mezhoud, C. Hamadache, V. Tatischeff, I. Bourgaoub, A. Gostojic, J. Peyré, F. Hammache, A. Coc, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Institut de Physique Nucléaire d'Orsay (IPNO)
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Nuclear reaction ,History ,Materials science ,Astrophysics::High Energy Astrophysical Phenomena ,Analytical chemistry ,FOS: Physical sciences ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,7. Clean energy ,01 natural sciences ,Education ,Cross section (physics) ,0103 physical sciences ,Emission spectrum ,Nuclear Experiment (nucl-ex) ,010306 general physics ,Nuclear Experiment ,Line (formation) ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Range (particle radiation) ,Solar flare ,010308 nuclear & particles physics ,Accelerator research and development ,Gamma ray ,Alpha particle ,Computer Science Applications ,Astrophysics - High Energy Astrophysical Phenomena ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Cross sections for the strongest gamma-ray emission lines produced in alpha-particle reactions with C, Mg, Si, Fe have been measured in the range E_alpha = 50 - 90 MeV at the center for proton therapy at the Helmholtz-Zentrum Berlin. Data for more than 60 different gamma-ray lines were determined, with particular efforts for lines that are in cross section compilations/evaluations with astrophysical purpose, and where data exist at lower projectile energies. The data are compared with predictions of a modern nuclear reaction code and cross-section curves of the latest evaluation for gamma-ray line emission in accelerated-particle interactions in solar flares., Comment: 5 pages, 5 figures, contribution to the XXIII International School on Nuclear Physics, Neutron Physics and Applications, Varna, Bulgaria, September 22-28, 2019
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- 2020
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5. Measurements of nuclearγ-ray line emission in interactions of protons andαparticles with N, O, Ne, and Si
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J.-P. Thibaud, J. C. Dalouzy, N. de Séréville, Vincent Tatischeff, S. Ouichaoui, H. Benhabiles-Mezhoud, Jürgen Kiener, A. Coc, F. Dayras, I. Deloncle, F. de Grancey, Livio Lamia, M. G. Pellegriti, J. Duprat, A. Lefebvre-Schuhl, C. Hamadache, and F. de Oliveira
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Nuclear reaction ,Physics ,Nuclear and High Energy Physics ,Proton ,010308 nuclear & particles physics ,Alpha particle ,Coupling (probability) ,01 natural sciences ,7. Clean energy ,Nuclear physics ,0103 physical sciences ,Production (computer science) ,Isotopes of silicon ,Atomic physics ,Nuclear Experiment ,010303 astronomy & astrophysics ,Energy (signal processing) ,Oxygen-16 - Abstract
$\ensuremath{\gamma}$-ray production cross sections have been measured in proton irradiations of N, Ne, and Si and $\ensuremath{\alpha}$-particle irradiations of N and Ne. In the same experiment we extracted also line shapes for strong $\ensuremath{\gamma}$-ray lines of $^{16}\mathrm{O}$ produced in proton and $\ensuremath{\alpha}$-particle irradiations of O. For the measurements gas targets were used for N, O, and Ne and a thick foil for Si. All targets were of natural isotopic composition. Beams in the energy range up to 26 MeV for protons and 39 MeV for $\ensuremath{\alpha}$ particles were delivered by the Institut de Physique Nucl\'eaire--Orsay tandem accelerator. The $\ensuremath{\gamma}$ rays were detected with four high-purity Ge detectors in the angular range ${30}^{\ifmmode^\circ\else\textdegree\fi{}}$ to ${135}^{\ifmmode^\circ\else\textdegree\fi{}}$. We extracted 36 cross-section excitation functions for proton reactions and 14 for $\ensuremath{\alpha}$-particle reactions. For the majority of the excitation functions no other data exist to our knowledge. Where comparison with existing data was possible, usually a very good agreement was found. It is shown that these data are very interesting for constraining nuclear reaction models. In particular, the agreement of cross section calculations in the nuclear reaction code talys with the measured data could be improved by adjusting the coupling schemes of collective levels in the target nuclei $^{14}\mathrm{N}$, $^{20,22}\mathrm{Ne}$, and $^{28}\mathrm{Si}$. The importance of these results for the modeling of nuclear $\ensuremath{\gamma}$-ray line emission in astrophysical sites is discussed.
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- 2011
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6. Discovery of a New Broad Resonance inNe19: Implications for the Destruction of the Cosmicγ-Ray EmitterF18
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A. Coc, M. Stanoiu, I. Stefan, F. Negoita, R. Borcea, Jürgen Kiener, J. C. Dalouzy, F. de Oliveira Santos, A. M. Sánchez-Benítez, P. J. Woods, N. de Séréville, C. Borcea, H. Benhabiles, P. Bourgault, A. Damman, A. Buta, Marialuisa Aliotta, O. Sorlin, L. Achouri, M. G. Pellegriti, Carmen Angulo, F. de Grancey, and Thomas Davinson
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Physics ,Degree (graph theory) ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Zero (complex analysis) ,General Physics and Astronomy ,Resonance ,Inelastic scattering ,01 natural sciences ,Angular correlation ,0103 physical sciences ,Atomic physics ,Proton emission ,Nuclear Experiment ,010306 general physics ,Spin-½ - Abstract
Six proton-emitting states in $^{19}\mathrm{Ne}$ were studied through the inelastic scattering reaction $\mathrm{H}(^{19}\mathrm{Ne},p)^{19}\mathrm{Ne}^{*}(p)^{18}\mathrm{F}$. Their energies and widths were derived from the protons detected at zero degree, while proton-proton angular correlations between the detector at zero degree and a segmented annular detector were used to determine their spin value. In addition to the known states, a new broad $J=\frac{1}{2}$ resonance has been evidenced at ${E}_{x}\ensuremath{\approx}7.9\text{ }\text{ }\mathrm{MeV}$, $\ensuremath{\approx}1.45\text{ }\text{ }\mathrm{MeV}$ above the proton emission threshold. By introducing this resonance, the $^{18}\mathrm{F}(p,\ensuremath{\alpha})^{15}\mathrm{O}$ destruction rate in novae is significantly enhanced. This reduces the chance to observe the cosmic $\ensuremath{\gamma}$-ray emission of $^{18}\mathrm{F}$ from novae in space telescopes.
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- 2009
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7. γ-ray production by proton and α-particle induced reactions onC12,O16,Mg24, and Fe
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J.-P. Thibaud, H. Benhabiles-Mezhoud, M. Gounelle, J. Duprat, A. Lefebvre-Schuhl, Marin Chabot, N. de Séréville, Cécile Engrand, Fairouz Hammache, Vincent Tatischeff, Jürgen Kiener, C. Fitoussi, A. Belhout, and A. Coc
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Physics ,Nuclear reaction ,Nuclear and High Energy Physics ,Range (particle radiation) ,Proton ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Analytical chemistry ,Inelastic scattering ,7. Clean energy ,01 natural sciences ,Bismuth germanate ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,Physics::Accelerator Physics ,Spallation ,Gamma spectroscopy ,Nuclear Experiment ,010303 astronomy & astrophysics ,Energy (signal processing) - Abstract
{gamma}-ray production cross sections for proton and {alpha}-particle interactions with {sup 12}C, {sup 16}O, {sup 24}Mg, and Fe have been measured in the energy range 5-25 MeV with proton beams and 5-40 MeV with {alpha}-particle beams. Isotopically pure foils of {sup 24}Mg and foils of natural isotopical composition of C, MgO, and Fe have been used. {gamma}-ray angular distributions were obtained with five high-purity Ge detectors with bismuth germanate Compton shields placed at angles of 45 deg. to 157.5 deg. Cross sections for more than 50 different {gamma}-ray transitions were extracted, and for many of them no data have been published before. Comparison of present data with data available in the literature shows mostly good to excellent agreement. In addition to the production cross sections, high-statistics, low-background line shapes of the 4.438 MeV {sup 12}C {gamma} ray from inelastic scattering off {sup 12}C and spallation of {sup 16}O were obtained. Comparison with nuclear reaction calculations shows that these data place interesting constraints on nuclear reaction models.
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- 2007
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8. ERRATUM: 'DEEXCITATION NUCLEAR GAMMA-RAY LINE EMISSION FROM LOW-ENERGY COSMIC RAYS IN THE INNER GALAXY' (2013, ApJ, 763, 98)
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Andrew W. Strong, Jürgen Kiener, H. Benhabiles-Mezhoud, and Vincent Tatischeff
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Physics ,Low energy ,Space and Planetary Science ,Gamma ray ,Astronomy ,Astronomy and Astrophysics ,Cosmic ray ,Astrophysics ,Galaxy ,Line (formation) - Published
- 2013
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9. DE-EXCITATION NUCLEAR GAMMA-RAY LINE EMISSION FROM LOW-ENERGY COSMIC RAYS IN THE INNER GALAXY
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Jürgen Kiener, Andrew W. Strong, Vincent Tatischeff, and H. Benhabiles-Mezhoud
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Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Interstellar cloud ,Gamma ray ,Astronomy and Astrophysics ,Cosmic ray ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Galaxy ,Spectral line ,Interstellar medium ,Space and Planetary Science ,Emission spectrum ,Nuclear Experiment ,Nucleon ,Astrophysics::Galaxy Astrophysics - Abstract
Recent observations of high ionization rates of molecular hydrogen in diffuse interstellar clouds point to a distinct low-energy cosmic-ray component. Supposing that this component is made of nuclei, two models for the origin of such particles are explored and low-energy cosmic-ray spectra are calculated, which, added to the standard cosmic-ray spectra, produce the observed ionization rates. The clearest evidence of the presence of such low-energy nuclei between a few MeV nucleon{sup -1} and several hundred MeV nucleon{sup -1} in the interstellar medium would be a detection of nuclear {gamma}-ray line emission in the range E {sub {gamma}} {approx} 0.1-10 MeV, which is strongly produced in their collisions with the interstellar gas and dust. Using a recent {gamma}-ray cross section compilation for nuclear collisions, {gamma}-ray line emission spectra are calculated alongside the high-energy {gamma}-ray emission due to {pi}{sup 0} decay, the latter providing normalization of the absolute fluxes by comparison with Fermi-LAT observations of the diffuse emission above E {sub {gamma}} = 0.1 GeV. Our predicted fluxes of strong nuclear {gamma}-ray lines from the inner Galaxy are well below the detection sensitivities of the International Gamma-Ray Astrophysics Laboratory, but a detection, especially of the 4.4 MeV line, seems possible with new-generationmore » {gamma}-ray telescopes based on available technology. We also predict strong {gamma}-ray continuum emission in the 1-8 MeV range, which, in a large part of our model space for low-energy cosmic rays, considerably exceeds the estimated instrument sensitivities of future telescopes.« less
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- 2013
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10. A Vision Transformer-Based Framework for Knowledge Transfer From Multi-Modal to Mono-Modal Lymphoma Subtyping Models.
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Guetarni B, Windal F, Benhabiles H, Petit M, Dubois R, Leteurtre E, and Collard D
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- Humans, Lymphoma, Algorithms, Deep Learning, Image Interpretation, Computer-Assisted methods, Lymphoma, Large B-Cell, Diffuse
- Abstract
Determining lymphoma subtypes is a crucial step for better patient treatment targeting to potentially increase their survival chances. In this context, the existing gold standard diagnosis method, which relies on gene expression technology, is highly expensive and time-consuming, making it less accessibility. Although alternative diagnosis methods based on IHC (immunohistochemistry) technologies exist (recommended by the WHO), they still suffer from similar limitations and are less accurate. Whole Slide Image (WSI) analysis using deep learning models has shown promising potential for cancer diagnosis, that could offer cost-effective and faster alternatives to existing methods. In this work, we propose a vision transformer-based framework for distinguishing DLBCL (Diffuse Large B-Cell Lymphoma) cancer subtypes from high-resolution WSIs. To this end, we introduce a multi-modal architecture to train a classifier model from various WSI modalities. We then leverage this model through a knowledge distillation process to efficiently guide the learning of a mono-modal classifier. Our experimental study conducted on a lymphoma dataset of 157 patients shows the promising performance of our mono-modal classification model, outperforming six recent state-of-the-art methods. In addition, the power-law curve, estimated on our experimental data, suggests that with more training data from a reasonable number of additional patients, our model could achieve competitive diagnosis accuracy with IHC technologies. Furthermore, the efficiency of our framework is confirmed through an additional experimental study on an external breast cancer dataset (BCI dataset).
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- 2024
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11. SuperpixelGridMasks Data Augmentation: Application to Precision Health and Other Real-world Data.
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Hammoudi K, Cabani A, Slika B, Benhabiles H, Dornaika F, and Melkemi M
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A novel approach of data augmentation based on irregular superpixel decomposition is proposed. This approach called SuperpixelGridMasks permits to extend original image datasets that are required by training stages of machine learning-related analysis architectures towards increasing their performances. Three variants named SuperpixelGridCut , SuperpixelGridMean , and SuperpixelGridMix are presented. These grid-based methods produce a new style of image transformations using the dropping and fusing of information. Extensive experiments using various image classification models as well as precision health and surrounding real-world datasets show that baseline performances can be significantly outperformed using our methods. The comparative study also shows that our methods can overpass the performances of other data augmentations. SuperpixelGridCut , SuperpixelGridMean , and SuperpixelGridMix codes are publicly available at https://github.com/hammoudiproject/SuperpixelGridMasks., Competing Interests: Competing InterestsThe authors declare no competing interests., (© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)
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- 2023
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12. Surface-based protein domains retrieval methods from a SHREC2021 challenge.
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Langenfeld F, Aderinwale T, Christoffer C, Shin WH, Terashi G, Wang X, Kihara D, Benhabiles H, Hammoudi K, Cabani A, Windal F, Melkemi M, Otu E, Zwiggelaar R, Hunter D, Liu Y, Sirugue L, Nguyen HH, Nguyen TH, Nguyen-Truong VT, Le D, Nguyen HD, Tran MT, and Montès M
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- Ligands, Models, Molecular, Protein Domains, Static Electricity, Proteins
- Abstract
Proteins are essential to nearly all cellular mechanism and the effectors of the cells activities. As such, they often interact through their surface with other proteins or other cellular ligands such as ions or organic molecules. The evolution generates plenty of different proteins, with unique abilities, but also proteins with related functions hence similar 3D surface properties (shape, physico-chemical properties, …). The protein surfaces are therefore of primary importance for their activity. In the present work, we assess the ability of different methods to detect such similarities based on the geometry of the protein surfaces (described as 3D meshes), using either their shape only, or their shape and the electrostatic potential (a biologically relevant property of proteins surface). Five different groups participated in this contest using the shape-only dataset, and one group extended its pre-existing method to handle the electrostatic potential. Our comparative study reveals both the ability of the methods to detect related proteins and their difficulties to distinguish between highly related proteins. Our study allows also to analyze the putative influence of electrostatic information in addition to the one of protein shapes alone. Finally, the discussion permits to expose the results with respect to ones obtained in the previous contests for the extended method. The source codes of each presented method have been made available online., (Copyright © 2021. Published by Elsevier Inc.)
- Published
- 2022
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13. An Evaluation of Computational Learning-based Methods for the Segmentation of Nuclei in Cervical Cancer Cells from Microscopic Images.
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Maylaa T, Windal F, Benhabiles H, Maubon G, Maubon N, Vandenhaute E, and Collard D
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- Algorithms, Cellular Structures, Female, Humans, Machine Learning, Image Processing, Computer-Assisted methods, Uterine Cervical Neoplasms
- Abstract
Background: The manual segmentation of cellular structures on Z-stack microscopic images is time-consuming and often inaccurate, highlighting the need to develop auto-segmentation tools to facilitate this process., Objective: This study aimed to compare the performance of three different machine learning architectures, including random forest (RF), AdaBoost, and multi-layer perceptron (MLP), for the autosegmentation of nuclei in proliferating cervical cancer cells on Z-Stack cellular microscopy proliferation images provided by the HCS Pharma. The impact of using post-processing techniques, such as the StarDist plugin and majority voting, was also evaluated., Methods: The RF, AdaBoost, and MLP algorithms were used to auto-segment the nuclei of cervical cancer cells on microscopic images at different Z-stack positions. Post-processing techniques were then applied to each algorithm. The performance of all algorithms was compared by an expert to globally generated ground truth by calculating the accuracy detection rate, the Dice coefficient, and the Jaccard index., Results: RF achieved the best accuracy, followed by the AdaBoost and then the MLP. All algorithms achieved good pixel classifications except in regions whereby the nuclei overlapped. The majority voting and StarDist plugin improved the accuracy of the segmentation but did not resolve the nuclei overlap issue. The Z-Stack analysis revealed similar segmentation results to the Z-stack layer used to train the image. However, a worse performance was noted for segmentations performed on different Z-stack positions, which were not used to train the algorithms., Conclusion: All machine learning architectures provided a good segmentation of nuclei in cervical cancer cells but did not resolve the problem of overlapping nuclei and Z-stack segmentation. Further research should therefore evaluate the combined segmentation techniques and deep learning architectures to resolve these issues., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
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- 2022
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14. Deep Learning on Chest X-ray Images to Detect and Evaluate Pneumonia Cases at the Era of COVID-19.
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Hammoudi K, Benhabiles H, Melkemi M, Dornaika F, Arganda-Carreras I, Collard D, and Scherpereel A
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- Algorithms, Humans, Neural Networks, Computer, X-Rays, COVID-19 diagnostic imaging, Deep Learning, Pneumonia, Viral diagnostic imaging, Radiography, Thoracic
- Abstract
Coronavirus disease 2019 (COVID-19) is an infectious disease with first symptoms similar to the flu. COVID-19 appeared first in China and very quickly spreads to the rest of the world, causing then the 2019-20 coronavirus pandemic. In many cases, this disease causes pneumonia. Since pulmonary infections can be observed through radiography images, this paper investigates deep learning methods for automatically analyzing query chest X-ray images with the hope to bring precision tools to health professionals towards screening the COVID-19 and diagnosing confirmed patients. In this context, training datasets, deep learning architectures and analysis strategies have been experimented from publicly open sets of chest X-ray images. Tailored deep learning models are proposed to detect pneumonia infection cases, notably viral cases. It is assumed that viral pneumonia cases detected during an epidemic COVID-19 context have a high probability to presume COVID-19 infections. Moreover, easy-to-apply health indicators are proposed for estimating infection status and predicting patient status from the detected pneumonia cases. Experimental results show possibilities of training deep learning models over publicly open sets of chest X-ray images towards screening viral pneumonia. Chest X-ray test images of COVID-19 infected patients are successfully diagnosed through detection models retained for their performances. The efficiency of proposed health indicators is highlighted through simulated scenarios of patients presenting infections and health problems by combining real and synthetic health data.
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- 2021
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15. MaskedFace-Net - A dataset of correctly/incorrectly masked face images in the context of COVID-19.
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Cabani A, Hammoudi K, Benhabiles H, and Melkemi M
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Wearing face masks appears as a solution for limiting the spread of COVID-19. In this context, efficient recognition systems are expected for checking that people faces are masked in regulated areas. Hence, a large dataset of masked faces is necessary for training deep learning models towards detecting people wearing masks and those not wearing masks. Currently, there are no available large dataset of masked face images that permits to check if faces are correctly masked or not. Indeed, many people are not correctly wearing their masks due to bad practices, bad behaviors or vulnerability of individuals (e.g., children, old people). For these reasons, several mask wearing campaigns intend to sensitize people about this problem and good practices. In this sense, this work proposes an image editing approach and three types of masked face detection dataset; namely, the Correctly Masked Face Dataset (CMFD), the Incorrectly Masked Face Dataset (IMFD) and their combination for the global masked face detection (MaskedFace-Net). Realistic masked face datasets are proposed with a twofold objective: i) detecting people having their faces masked or not masked, ii) detecting faces having their masks correctly worn or incorrectly worn (e.g.; at airport portals or in crowds). To the best of our knowledge, no large dataset of masked faces provides such a granularity of classification towards mask wearing analysis. Moreover, this work globally presents the applied mask-to-face deformable model for permitting the generation of other masked face images, notably with specific masks. Our datasets of masked faces (137,016 images) are available at https://github.com/cabani/MaskedFace-Net. The dataset of face images Flickr-Faces-HQ3 (FFHQ), publicly made available online by NVIDIA Corporation, has been used for generating MaskedFace-Net., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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16. 2,6-Diaminopurine as a highly potent corrector of UGA nonsense mutations.
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Trzaska C, Amand S, Bailly C, Leroy C, Marchand V, Duvernois-Berthet E, Saliou JM, Benhabiles H, Werkmeister E, Chassat T, Guilbert R, Hannebique D, Mouray A, Copin MC, Moreau PA, Adriaenssens E, Kulozik A, Westhof E, Tulasne D, Motorin Y, Rebuffat S, and Lejeune F
- Subjects
- Animals, Disease Models, Animal, Gene Expression Regulation, Neoplastic drug effects, Genes, p53 genetics, HEK293 Cells, HeLa Cells, Humans, Lepisma chemistry, Mice, Mice, Nude, RNA, Transfer genetics, tRNA Methyltransferases metabolism, 2-Aminopurine analogs & derivatives, 2-Aminopurine pharmacology, Codon, Nonsense drug effects, Drug Discovery, Drug Screening Assays, Antitumor, Mutation drug effects
- Abstract
Nonsense mutations cause about 10% of genetic disease cases, and no treatments are available. Nonsense mutations can be corrected by molecules with nonsense mutation readthrough activity. An extract of the mushroom Lepista inversa has recently shown high-efficiency correction of UGA and UAA nonsense mutations. One active constituent of this extract is 2,6-diaminopurine (DAP). In Calu-6 cancer cells, in which TP53 gene has a UGA nonsense mutation, DAP treatment increases p53 level. It also decreases the growth of tumors arising from Calu-6 cells injected into immunodeficient nude mice. DAP acts by interfering with the activity of a tRNA-specific 2'-O-methyltransferase (FTSJ1) responsible for cytosine 34 modification in tRNA
Trp . Low-toxicity and high-efficiency UGA nonsense mutation correction make DAP a good candidate for the development of treatments for genetic diseases caused by nonsense mutations.- Published
- 2020
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17. Optimized approach for the identification of highly efficient correctors of nonsense mutations in human diseases.
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Benhabiles H, Gonzalez-Hilarion S, Amand S, Bailly C, Prévotat A, Reix P, Hubert D, Adriaenssens E, Rebuffat S, Tulasne D, and Lejeune F
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- Base Sequence, Codon, Terminator, Cystic Fibrosis genetics, Cystic Fibrosis therapy, HeLa Cells, Humans, Nonsense Mediated mRNA Decay, RNA, Messenger genetics, Codon, Nonsense, Genetic Predisposition to Disease
- Abstract
About 10% of patients with a genetic disease carry a nonsense mutation causing their pathology. A strategy for correcting nonsense mutations is premature termination codon (PTC) readthrough, i.e. incorporation of an amino acid at the PTC position during translation. PTC-readthrough-activating molecules appear as promising therapeutic tools for these patients. Unfortunately, the molecules shown to induce PTC readthrough show low efficacy, probably because the mRNAs carrying a nonsense mutation are scarce, as they are also substrates of the quality control mechanism called nonsense-mediated mRNA decay (NMD). The screening systems previously developed to identify readthrough-promoting molecules used cDNA constructs encoding mRNAs immune to NMD. As the molecules identified were not selected for the ability to correct nonsense mutations on NMD-prone PTC-mRNAs, they could be unsuitable for the context of nonsense-mutation-linked human pathologies. Here, a screening system based on an NMD-prone mRNA is described. It should be suitable for identifying molecules capable of efficiently rescuing the expression of human genes harboring a nonsense mutation. This system should favor the discovery of candidate drugs for treating genetic diseases caused by nonsense mutations. One hit selected with this screening system is presented and validated on cells from three cystic fibrosis patients.
- Published
- 2017
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18. Discovery of a new broad resonance in 19Ne: implications for the destruction of the cosmic gamma-ray emitter 18F.
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Dalouzy JC, Achouri L, Aliotta M, Angulo C, Benhabiles H, Borcea C, Borcea R, Bourgault P, Buta A, Coc A, Damman A, Davinson T, de Grancey F, de Oliveira Santos F, de Séréville N, Kiener J, Pellegriti MG, Negoita F, Sánchez-Benítez AM, Sorlin O, Stanoiu M, Stefan I, and Woods PJ
- Abstract
Six proton-emitting states in 19Ne were studied through the inelastic scattering reaction H(19Ne,p);{19}Ne; (p)18F. Their energies and widths were derived from the protons detected at zero degree, while proton-proton angular correlations between the detector at zero degree and a segmented annular detector were used to determine their spin value. In addition to the known states, a new broad J=1/2 resonance has been evidenced at E_{x} approximately 7.9 MeV, approximately 1.45 MeV above the proton emission threshold. By introducing this resonance, the 18F(p,alpha)15O destruction rate in novae is significantly enhanced. This reduces the chance to observe the cosmic gamma-ray emission of 18F from novae in space telescopes.
- Published
- 2009
- Full Text
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