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4,380 results on '"Rahier A"'

1. Logarithmic Regret for Unconstrained Submodular Maximization Stochastic Bandit

Author

Zhou, Julien, Gaillard, Pierre, Rahier, Thibaud, and Arbel, Julyan

Subjects
Computer Science - Machine Learning, Mathematics - Combinatorics, Mathematics - Optimization and Control, Statistics - Machine Learning
Abstract

We address the online unconstrained submodular maximization problem (Online USM), in a setting with stochastic bandit feedback. In this framework, a decision-maker receives noisy rewards from a nonmonotone submodular function, taking values in a known bounded interval. This paper proposes Double-Greedy - Explore-then-Commit (DG-ETC), adapting the Double-Greedy approach from the offline and online full-information settings. DG-ETC satisfies a O(d log(dT)) problemdependent upper bound for the 1/2-approximate pseudo-regret, as well as a O(dT^{2/3}log(dT)^{1/3}) problem-free one at the same time, outperforming existing approaches. To that end, we introduce a notion of hardness for submodular functions, characterizing how difficult it is to maximize them with this type of strategy.

Published
2024

3. Towards Efficient and Optimal Covariance-Adaptive Algorithms for Combinatorial Semi-Bandits

Author

Zhou, Julien, Gaillard, Pierre, Rahier, Thibaud, Zenati, Houssam, and Arbel, Julyan

Subjects
Computer Science - Machine Learning, Mathematics - Statistics Theory, Statistics - Machine Learning
Abstract

We address the problem of stochastic combinatorial semi-bandits, where a player selects among $P$ actions from the power set of a set containing $d$ base items. Adaptivity to the problem's structure is essential in order to obtain optimal regret upper bounds. As estimating the coefficients of a covariance matrix can be manageable in practice, leveraging them should improve the regret. We design ``optimistic'' covariance-adaptive algorithms relying on online estimations of the covariance structure, called OLSUCBC and COSV (only the variances for the latter). They both yields improved gap-free regret. Although COSV can be slightly suboptimal, it improves on computational complexity by taking inspiration from Thompson Sampling approaches. It is the first sampling-based algorithm satisfying a $\sqrt{T}$ gap-free regret (up to poly-logs). We also show that in some cases, our approach efficiently leverages the semi-bandit feedback and outperforms bandit feedback approaches, not only in exponential regimes where $P\gg d$ but also when $P\leq d$, which is not covered by existing analyses.

Published
2024

4. Maximizing the Success Probability of Policy Allocations in Online Systems

Author

Betlei, Artem, Vladimirova, Mariia, Sebbar, Mehdi, Urien, Nicolas, Rahier, Thibaud, and Heymann, Benjamin

Subjects
Computer Science - Information Retrieval, Computer Science - Computer Science and Game Theory, Computer Science - Machine Learning, Statistics - Machine Learning
Abstract

The effectiveness of advertising in e-commerce largely depends on the ability of merchants to bid on and win impressions for their targeted users. The bidding procedure is highly complex due to various factors such as market competition, user behavior, and the diverse objectives of advertisers. In this paper we consider the problem at the level of user timelines instead of individual bid requests, manipulating full policies (i.e. pre-defined bidding strategies) and not bid values. In order to optimally allocate policies to users, typical multiple treatments allocation methods solve knapsack-like problems which aim at maximizing an expected value under constraints. In the industrial contexts such as online advertising, we argue that optimizing for the probability of success is a more suited objective than expected value maximization, and we introduce the SuccessProbaMax algorithm that aims at finding the policy allocation which is the most likely to outperform a fixed reference policy. Finally, we conduct comprehensive experiments both on synthetic and real-world data to evaluate its performance. The results demonstrate that our proposed algorithm outperforms conventional expected-value maximization algorithms in terms of success rate., Comment: accepted to AAAI 2024, 7 pages main text, 9 pages references and appendix, 22 figures

Published
2023

5. Vibration Analysis in Mining: The Technology Spectrum

Author

Rahier, Ryan

Subjects
Mineral industry, Mining industry, Mines and mineral resources, Business, Engineering and manufacturing industries, Petroleum, energy and mining industries
Abstract

Recently, a mining company with an operation in the initial production stages inquired about collecting baseline vibration readings. While they understood this practice had value, their knowledge of it was [...]

Published
2024

7. Nested bandits

Author

Martin, Matthieu, Mertikopoulos, Panayotis, Rahier, Thibaud, and Zenati, Houssam

Subjects
Computer Science - Machine Learning, Computer Science - Computer Science and Game Theory, Mathematics - Optimization and Control, Primary 68Q32, secondary 91B06
Abstract

In many online decision processes, the optimizing agent is called to choose between large numbers of alternatives with many inherent similarities; in turn, these similarities imply closely correlated losses that may confound standard discrete choice models and bandit algorithms. We study this question in the context of nested bandits, a class of adversarial multi-armed bandit problems where the learner seeks to minimize their regret in the presence of a large number of distinct alternatives with a hierarchy of embedded (non-combinatorial) similarities. In this setting, optimal algorithms based on the exponential weights blueprint (like Hedge, EXP3, and their variants) may incur significant regret because they tend to spend excessive amounts of time exploring irrelevant alternatives with similar, suboptimal costs. To account for this, we propose a nested exponential weights (NEW) algorithm that performs a layered exploration of the learner's set of alternatives based on a nested, step-by-step selection method. In so doing, we obtain a series of tight bounds for the learner's regret showing that online learning problems with a high degree of similarity between alternatives can be resolved efficiently, without a red bus / blue bus paradox occurring., Comment: 35 pages, 14 figures; to appear in ICML 2022

Published
2022

8. Diverse Weight Averaging for Out-of-Distribution Generalization

Author

Ramé, Alexandre, Kirchmeyer, Matthieu, Rahier, Thibaud, Rakotomamonjy, Alain, Gallinari, Patrick, and Cord, Matthieu

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Artificial Intelligence, Computer Science - Machine Learning
Abstract

Standard neural networks struggle to generalize under distribution shifts in computer vision. Fortunately, combining multiple networks can consistently improve out-of-distribution generalization. In particular, weight averaging (WA) strategies were shown to perform best on the competitive DomainBed benchmark; they directly average the weights of multiple networks despite their nonlinearities. In this paper, we propose Diverse Weight Averaging (DiWA), a new WA strategy whose main motivation is to increase the functional diversity across averaged models. To this end, DiWA averages weights obtained from several independent training runs: indeed, models obtained from different runs are more diverse than those collected along a single run thanks to differences in hyperparameters and training procedures. We motivate the need for diversity by a new bias-variance-covariance-locality decomposition of the expected error, exploiting similarities between WA and standard functional ensembling. Moreover, this decomposition highlights that WA succeeds when the variance term dominates, which we show occurs when the marginal distribution changes at test time. Experimentally, DiWA consistently improves the state of the art on DomainBed without inference overhead., Comment: 36 pages, 16 figures, 15 tables

Published
2022

9. A Large Scale Benchmark for Individual Treatment Effect Prediction and Uplift Modeling

Author

Diemert, Eustache, Betlei, Artem, Renaudin, Christophe, Amini, Massih-Reza, Gregoir, Théophane, and Rahier, Thibaud

Subjects
Statistics - Machine Learning, Computer Science - Artificial Intelligence, Computer Science - Machine Learning, Statistics - Applications
Abstract

Individual Treatment Effect (ITE) prediction is an important area of research in machine learning which aims at explaining and estimating the causal impact of an action at the granular level. It represents a problem of growing interest in multiple sectors of application such as healthcare, online advertising or socioeconomics. To foster research on this topic we release a publicly available collection of 13.9 million samples collected from several randomized control trials, scaling up previously available datasets by a healthy 210x factor. We provide details on the data collection and perform sanity checks to validate the use of this data for causal inference tasks. First, we formalize the task of uplift modeling (UM) that can be performed with this data, along with the relevant evaluation metrics. Then, we propose synthetic response surfaces and heterogeneous treatment assignment providing a general set-up for ITE prediction. Finally, we report experiments to validate key characteristics of the dataset leveraging its size to evaluate and compare - with high statistical significance - a selection of baseline UM and ITE prediction methods.

Published
2021

10. Zeroth-order non-convex learning via hierarchical dual averaging

Author

Héliou, Amélie, Martin, Matthieu, Mertikopoulos, Panayotis, and Rahier, Thibaud

Subjects
Computer Science - Machine Learning, Mathematics - Optimization and Control, Primary 68Q32, 90C56, secondary 90C15, 90C26
Abstract

We propose a hierarchical version of dual averaging for zeroth-order online non-convex optimization - i.e., learning processes where, at each stage, the optimizer is facing an unknown non-convex loss function and only receives the incurred loss as feedback. The proposed class of policies relies on the construction of an online model that aggregates loss information as it arrives, and it consists of two principal components: (a) a regularizer adapted to the Fisher information metric (as opposed to the metric norm of the ambient space); and (b) a principled exploration of the problem's state space based on an adapted hierarchical schedule. This construction enables sharper control of the model's bias and variance, and allows us to derive tight bounds for both the learner's static and dynamic regret - i.e., the regret incurred against the best dynamic policy in hindsight over the horizon of play., Comment: 40 pages, 14 figures

Published
2021

11. Development of calcium sulfoaluminate cements from rich‐alumina bauxite and marble wastes: Physicochemical and microstructural characterization

Author

Gaëlle Annick Nyonda Yanze, Achile Nana, Patrick Ninla Lemougna, Rodrigue Cyriaque Kaze, Sylvain Tome, Hubert Rahier, Elie Kamseu, and Florence Uphie Chinje

Subjects
calcium sulfoaluminate cement, gypsum, microstructure, mintom limestone, rich alumina bauxite, Clay industries. Ceramics. Glass, TP785-869
Abstract

Abstract This work discusses the effect of rich alumina bauxite on the mineralogical composition of calcium sulfoaluminate (CSA) clinker cement on their performances. After preparation of different local raw materials (rich alumina bauxite and marble), they were mixed with 15 wt% of commercial gypsum and pressed at 2 MPa. The obtained pellets were thermally treated at 1200°C to produce clinker, which is use to synthesize the CSA cements. The raw materials as well as products were characterized by many analyses, such as FT‐IR, X‐ray fluorescence, X‐ray diffraction, differential scanning calorimetry (DSC)/thermogravimetry analysis (TGA), isothermal calorimetry (ICC), scanning electron microscope, and physico‐mechanical tests. ICC analysis of the powder of clinker cement showed that the reactions are strongly affected by gypsum content. XRD results revealed that clinker and cement present a strong intensity of ye'elimite as main mineral phase. Moreover, the hydrated cement exhibited ettringite and monosulfate as the new phases formed. The compressive strength of hydrated cement reached ∼21 and 28 MPa after 1 and 28 days of curing, respectively. From the aforementioned results, this local rich alumina bauxite can be used to produce high‐strength cement for self‐leveling materials, which allow their use in engineering and building applications.

Published
2024
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12. Encapsulation of Trichoderma reesei and Neurospora crassa in calcium alginate capsules for fungi-mediated self-healing concrete: An explorative study on the protocol, survival of the organisms and CaCO3 biomineralization

Author

Aurélie Van Wylick, Emmeline Brouwers, Hubert Rahier, Eveline Peeters, and Lars De Laet

Subjects
Encapsulation, Biomineralization, Calcium carbonate, Self-healing concrete, Trichoderma reesei, Neurospora crassa, Engineering (General). Civil engineering (General), TA1-2040, Building construction, TH1-9745
Abstract

Concrete, a predominant building material, is known for its material degradation due to crack formation. The associated durability concerns initiated the use of microorganisms to self-heal concrete cracks by promoting CaCO3 precipitation on their cell walls. Filamentous fungi grow in mycelial networks that provide abundant nucleation sites for the precipitation. As demonstrated by the research on bacteria, protection of the microorganism in the concrete mix is crucial to safeguard its survival. In this work, an encapsulation method based on sodium alginate and calcium lactate was identified in the bacteria-based literature and adapted to the fungi Trichoderma reesei and Neurospora crassa. Results showed spore survival after the encapsulation procedure, however survival was negated when immersed in concrete-relevant conditions. Simultaneously, biomass formation and CaCO3 biomineralization were quantified in liquid media. This study features possibilities to optimize the encapsulation procedure and aids the identification of optimal biomineralization conditions.

Published
2024
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15. A Pre-screening Approach for Faster Bayesian Network Structure Learning

Author

Rahier, Thibaud, Marié, Sylvain, Forbes, Florence, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Amini, Massih-Reza, editor, Canu, Stéphane, editor, Fischer, Asja, editor, Guns, Tias, editor, Kralj Novak, Petra, editor, and Tsoumakas, Grigorios, editor

Published
2023
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18. Conditions for CaCO3 Biomineralization by Trichoderma Reesei with the Perspective of Developing Fungi‐Mediated Self‐Healing Concrete

Author

Aurélie Van Wylick, Hubert Rahier, Lars De Laet, and Eveline Peeters

Subjects
biomineralization, calcium carbonate, fungi, self‐healing concrete, trichoderma reesei, Technology, Environmental sciences, GE1-350
Abstract

Abstract Concrete, a widely used building material, often suffers from cracks that lead to corrosion and degradation. A promising solution to enhance its durability is the use of fungi as self‐healing agents, specifically by harnessing their ability to promote calcium carbonate (CaCO3) precipitation on their cell walls. However, the ideal conditions for CaCO3 precipitation by the filamentous fungal species Trichoderma reesei are still unclear. In this study, the biomineralization properties of T. reesei in liquid media are investigated. Two different calcium sources, calcium chloride (CaCl2) and calcium lactate are tested, at varying concentrations and in the presence of different nutritional sources that support growth of T. reesei. This study also explores the effects on fungal growth upon adding cement to the medium. Calcium lactate promotes greater fungal biomass production, although less crystals are formed as compared to samples with CaCl2. An increasing calcium concentration positively influences fungal growth and precipitation, but this effect is hindered upon the addition of cement. The highest amounts of biomass and calcium carbonate precipitation are achieved with potato dextrose broth as a nutritional source. By identifying the optimal conditions for CaCO3 precipitation by T. reesei, this study highlights its potential as a self‐healing agent in concrete.

Published
2024
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19. Online non-convex optimization with imperfect feedback

Author

Héliou, Amélie, Martin, Matthieu, Mertikopoulos, Panayotis, and Rahier, Thibaud

Subjects
Computer Science - Machine Learning, Mathematics - Optimization and Control, Primary 68Q32, secondary 90C26, 91A26
Abstract

We consider the problem of online learning with non-convex losses. In terms of feedback, we assume that the learner observes - or otherwise constructs - an inexact model for the loss function encountered at each stage, and we propose a mixed-strategy learning policy based on dual averaging. In this general context, we derive a series of tight regret minimization guarantees, both for the learner's static (external) regret, as well as the regret incurred against the best dynamic policy in hindsight. Subsequently, we apply this general template to the case where the learner only has access to the actual loss incurred at each stage of the process. This is achieved by means of a kernel-based estimator which generates an inexact model for each round's loss function using only the learner's realized losses as input., Comment: 30 pages, 2 figures, 1 table

Published
2020

20. Individual Treatment Prescription Effect Estimation in a Low Compliance Setting

Author

Rahier, Thibaud, Héliou, Amélie, Martin, Matthieu, Renaudin, Christophe, and Diemert, Eustache

Subjects
Statistics - Machine Learning, Computer Science - Machine Learning, Statistics - Methodology
Abstract

Individual Treatment Effect (ITE) estimation is an extensively researched problem, with applications in various domains. We model the case where there exists heterogeneous non-compliance to a randomly assigned treatment, a typical situation in health (because of non-compliance to prescription) or digital advertising (because of competition and ad blockers for instance). The lower the compliance, the more the effect of treatment prescription, or individual prescription effect (IPE), signal fades away and becomes hard to estimate. We propose a new approach for the estimation of the IPE that takes advantage of observed compliance information to prevent signal fading. Using the Structural Causal Model framework and do-calculus, we define a general mediated causal effect setting and propose a corresponding estimator which consistently recovers the IPE with asymptotic variance guarantees. Finally, we conduct experiments on both synthetic and real-world datasets that highlight the benefit of the approach, which consistently improves state-of-the-art in low compliance settings, Comment: 28 pages, 10 figures

Published
2020

21. Tasting 'kienyeji': gustatory explorations of city futures in Nakuru, Kenya

Author

Rahier, Nick

Subjects
Nakuru, Kenya -- Food and nutrition, City planning -- Forecasts and trends, Food habits -- Forecasts and trends, Market trend/market analysis, History
Abstract

Abstract In Nakuru, a secondary city in Kenya, the city's future is explored multi-sensorially. In this article, I argue that Nakuru residents explore urban futures through the taste of different [...]

Published
2023
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22. HLA-DP on Epithelial Cells Enables Tissue Damage by NKp44+ Natural Killer Cells in Ulcerative Colitis

Author

Akar, Alaa, Flemming, Cornelius, Felix, Flomm, Flosbach, Markus, Jäger, Julia, Jeromin, Niklas, Jung, Johannes, Ohms, Mareike, Reinshagen, Konrad, Rische, Johann, Sagebiel, Adrian, Sandfort, Deborah, Steinert, Fenja, Tomuschat, Christian, Wesche, Jasmin, Shifteh Abedian, Abraham, Clara, Achkar, Jean-Paul, Ahmad, Tariq, Alberts, Rudi, Alizadeh, Behrooz, Amininejad, Leila, Ananthakrishnan, Ashwin N., Andersen, Vibeke, Anderson, Carl A., Andrews, Jane M., Annese, Vito, Aumais, Guy, Baidoo, Leonard, Baldassano, Robert N., Bampton, Peter A., Barclay, Murray, Barrett, Jeffrey C., Bethge, Johannes, Bewshea, Claire, Bis, Joshua C., Bitton, Alain, BK, Thelma, Boucher, Gabrielle, Brain, Oliver, Brand, Stephan, Brant, Steven R., Cheon, Jae Hee, Chew, Angela, Cho, Judy H., Cleynen, Isabelle, Cohain, Ariella, Cooney, Rachel, Croft, Anthony, Daly, Mark J., D'Amato, Mauro, Danese, Silvio, Daryani, Naser Ebrahim, Datta, Lisa Wu, Degenhardt, Frauke, Denapiene, Goda, Denson, Lee A., Devaney, Kathy L., Dewit, Olivier, D'Inca, Renata, Drummond, Hazel E., Dubinsky, Marla, Duerr, Richard H., Edwards, Cathryn, Ellinghaus, David, Ellul, Pierre, Esaki, Motohiro, Essers, Jonah, Ferguson, Lynnette R., Festen, Eleonora A., Fleshner, Philip, Florin, Tim, Franchimont, Denis, Franke, Andre, Fuyuno, Yuta, Gearry, Richard, Georges, Michel, Gieger, Christian, Glas, Jürgen, Goyette, Philippe, Green, Todd, Griffiths, Anne M., Guthery, Stephen L., Hakonarson, Hakon, Halfvarson, Jonas, Hanigan, Katherine, Haritunians, Talin, Hart, Ailsa, Hawkey, Chris, Hayward, Nicholas K., Hedl, Matija, Henderson, Paul, Hold, Georgina L., Hong, Myhunghee, Hu, Xinli, Huang, Hailiang, Hugot, Jean-Pierre, Hui, Ken Y., Imielinski, Marcin, Jazayeri, Omid, Jonaitis, Laimas, Jostins, Luke, Juyal, Garima, Chandra Juyal, Ramesh, Kalla, Rahul, Karlsen, Tom H., Kennedy, Nicholas A., Khan, Mohammed Azam, Kim, Won Ho, Kitazono, Takanari, Kiudelis, Gediminas, Kubo, Michiaki, Kugathasan, Subra, Kupcinskas, Limas, Lamb, Christopher A., de Lange, Katrina M., Latiano, Anna, Laukens, Debby, Lawrance, Ian C., Lee, James C., Lees, Charlie W., Leja, Marcis, Lewis, Nina, Van Limbergen, Johan, Lionetti, Paolo, Liu, Jimmy Z., Louis, Edouard, Luo, Yang, Mahy, Gillian, Malekzadeh, Masoud Mohammad, Malekzadeh, Reza, Mansfield, John, Marriott, Suzie, Massey, Dunecan, Mathew, Christopher G., Matsui, Toshiyuki, McGovern, Dermot P.B., van der Meulen, Andrea, Midha, Vandana, Milgrom, Raquel, Mirzaei, Samaneh, Mitrovic, Mitja, Montgomery, Grant W., Mowat, Craig, Müller, Christoph, Newman, William G., Ng, Aylwin, Ng, Siew C., Evelyn Ng, Sok Meng, Nikolaus, Susanna, Ning, Kaida, Nöthen, Markus, Oikonomou, Ioannis, Okou, David, Orchard, Timothy R., Palmieri, Orazio, Parkes, Miles, Phillips, Anne, Ponsioen, Cyriel Y., Potocnik, Urõs, Poustchi, Hossein, Prescott, Natalie J., Proctor, Deborah D., Radford-Smith, Graham, Rahier, Jean- Francois, Regueiro, Miguel, Reinisch, Walter, Rieder, Florian, Rioux, John D., Roberts, Rebecca, Rogler, Gerhard, Russell, Richard K., Sanderson, Jeremy D., Sans, Miquel, Satsangi, Jack, Schadt, Eric E., Scharl, Michael, Schembri, John, Schreiber, Stefan, Schumm, L. Philip, Scott, Regan, Seielstad, Mark, Shah, Tejas, Sharma, Yashoda, Silverberg, Mark S., Simmons, Alison, Simms, Lisa A., Singh, Abhey, Skieceviciene, Jurgita, van Sommeren, Suzanne, Song, Kyuyoung, Sood, Ajit, Spain, Sarah L., Steinhart, A. Hillary, Stempak, Joanne M., Stronati, Laura, Sung, Joseph J.Y., Targan, Stephan R., Taylor, Kirstin M., Theatre, Emilie, Torkvist, Leif, Torres, Esther A., Tremelling, Mark, Uhlig, Holm H., Umeno, Junji, Vahedi, Homayon, Vasiliauskas, Eric, Velde, Anje ter, Ventham, Nicholas T., Vermeire, Severine, Verspaget, Hein W., De Vos, Martine, Walters, Thomas, Wang, Kai, Wang, Ming-Hsi, Weersma, Rinse K., Wei, Zhi, Whiteman, David, Wijmenga, Cisca, Wilson, David C., Winkelmann, Juliane, Wong, Sunny H., Xavier, Ramnik J., Yamazaki, Keiko, Yang, Suk-Kyun, Ye, Byong Duk, Zeissig, Sebastian, Zhang, Bin, Zhang, Clarence K., Zhang, Hu, Zhang, Wei, Zhao, Hongyu, Zhao, Zhen Z., Baumdick, Martin E., Niehrs, Annika, Schwerk, Maria, Hinrichs, Ole, Jordan-Paiz, Ana, Padoan, Benedetta, Wegner, Lucy H.M., Schloer, Sebastian, Zecher, Britta F., Malsy, Jakob, Joshi, Vinita R., Illig, Christin, Schröder-Schwarz, Jennifer, Möller, Kimberly J., Martin, Maureen P., Yuki, Yuko, Ozawa, Mikki, Sauter, Jürgen, Schmidt, Alexander H., Perez, Daniel, Giannou, Anastasios D., Carrington, Mary, Davis, Randall S., Schumacher, Udo, Sauter, Guido, Huber, Samuel, Puelles, Victor G., Melling, Nathaniel, Altfeld, Marcus, and Bunders, Madeleine J.

Published
2023
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24. Hourglass Bladder Deformity Induced by Chronic Ketamine Abuse

Author

Kevin Badran, Olivier Rahier, and Emmanuel Agneessens

Subjects
bladder, ketamine, hourglass, ct scan, ultrasound, Medical physics. Medical radiology. Nuclear medicine, R895-920
Abstract

Regular and chronic use of ketamine causes inflammatory changes in the urinary tract. Imaging has a crucial role in the assessment of this pathology. A particular imaging characteristic of an hourglass-shaped bladder is highlighted in three cases of ketamine intoxication. Teaching point: Three cases of ketamine intoxication with a characteristic bladder deformation are reported.

Published
2024
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25. Thermal Reactivation of Hydrated Cement Paste: Properties and Impact on Cement Hydration

Author

Asghar Gholizadeh-Vayghan, Guillermo Meza Hernandez, Felicite Kingne Kingne, Jun Gu, Nicole Dilissen, Michael El Kadi, Tine Tysmans, Jef Vleugels, Hubert Rahier, and Ruben Snellings

Subjects
recycled cement paste, thermal activation, reactivity, supplementary cementitious material, blended cement, hydration, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, QC120-168.85
Abstract

In this research, the properties and cementitious performance of thermally activated cement pastes (referred to as DCPs) are investigated. Hydrated pastes prepared from Portland cement and slag blended cement were subjected to different thermal treatments: 350 °C for 2 h, 550 °C for 2 h, 550 °C for 24 h and 750 °C for 2 h. The properties and the reactivity as SCM of the DCPs were characterised as well as their effect on the mechanical performance and hydration of new blended cements incorporating the DCPs as supplementary cementitious materials (SCMs). It was observed that the temperature and duration of the thermal treatment increased the grindability and BET specific surface area of the DCP, as well as the formation of C2S phases and the reactivity as SCM. In contrast, the mechanical strength results for the blended cements indicated that thermal treatment at 350 °C for 2 h provided better performance. The hydration study results showed that highly reactive DCP interfered with the early hydration of the main clinker phases in Portland cement, leading to early setting and slow strength gain. The effect on blended cement hydration was most marked for binary Portland cement–DCP blends. In contrast, in the case of ternary slag cement–DCP blends the use of reactive DCP as SCM enabled to significantly increase early age strength.

Published
2024
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26. Avulsion of the Ossification Center of the Iliac Crest in a Sporty Teenager: Multimodal Imaging Approach with Emphasis on the Role of the oZTEo MRI Pseudo-CT Sequence

Author

Quentin Rahier, Géraldine Debehogne, and Frédéric E. Lecouvet

Subjects
apophysis, avulsion, sport injuries, mri, zte sequence, zero echo time, Medical physics. Medical radiology. Nuclear medicine, R895-920
Abstract

Teaching point: The appearance of an avulsion of the ossification center of the iliac crest is reported on ultrasound, radiographs, and magnetic resonance imaging (MRI), with emphasis on the role of the “pseudo-CT” zero echo time (oZTEo) sequence to highlight the lesion.

Published
2024
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27. Alkali-Activated Copper Slag with Carbon Reinforcement: Effects of Metakaolinite, OPC and Surfactants

Author

Patrick Ninla Lemougna, Guillermo Meza Hernandez, Nicole Dilissen, Felicite Kingne, Jun Gu, and Hubert Rahier

Subjects
copper slag, alkali-activated materials, laminate composite, elastic modulus, flexural strength, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, QD1-999
Abstract

Copper slag is an industrial residue with a large unutilized fraction. This study presents the development of alkali-activated composites from a copper slag named Koranel®. The effects of metakaolinite, ordinary Portland cement (OPC) and surfactants were investigated. The reactivity of Koranel with potassium silicate solutions with molar ratio R = SiO2/K2O varying from 1 to 2.75, with 0.25 intervals, was investigated using isothermal calorimetry. The reactivity was relatively low at 20 °C; the reaction started after a few hours with a low silica modulus, to several weeks with the highest silica modulus. The substitution of Koranel by OPC (5 wt.%) or by metakaolinite (10–20 wt.%), both led to higher reaction heat and rate; meanwhile, the addition of 2 wt.% polyethylene glycol/2-methyl 2,4 pentanediol delayed the reaction time in the system containing metakaolinite. Raising the curing temperature from 20 °C to 80 °C shortened the setting time of the low reactive systems, from several days to almost instantaneous, opening perspectives for their application in the production of prepreg composite materials. The use of carbon fabric as reinforcement in the alkali-activated matrix led to composite materials with flexural strength reaching 88 MPa and elastic modulus of about 19 GPa—interesting for engineering applications such as high-strength lightweight panels.

Published
2024
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29. Withdrawal of infliximab or concomitant immunosuppressant therapy in patients with Crohn's disease on combination therapy (SPARE): a multicentre, open-label, randomised controlled trial

Author

Andrews, Jane, Sparrow, Miles, Leong, Rupert, Connor, Susan, Radforth-Smith, Graham, De Cruz, Peter, Preiss, Jan, Stallmach, Andrea, Liceni, Thomas, Grip, Olaf, Halfvarson, Jonas, Durai, Dharmaraj, Cummings, Fraser, Seilinger, Christian, Parkes, Miles, Lindsay, James, Lambrecht, Guy, Van Hootegem, Philippe, Rahier, Jean-François, Dewitte, Marie, Hebuterne, Xavier, Chanteloup, Elise, Altwegg, Romain, Nancey, Stephane, Bouguen, Guillaume, Pineton de Chambrun, Guillaume, Poullenot, Floriant, Roblin, Xavier, Louis, Edouard, Resche-Rigon, Matthieu, Laharie, David, Satsangi, Jack, Ding, Nik, Siegmund, Britta, D'Haens, Geert, Picon, Laurence, Bossuyt, Peter, Vuitton, Lucine, Irving, Peter, Viennot, Stephanie, Lamb, Christopher A, Pollok, Richard, Baert, Filip, Nachury, Maria, Fumery, Mathurin, Gilletta, Cyrielle, Almer, Sven, Ben-Horin, Shomron, Bouhnik, Yoram, Colombel, Jean-Frederic, and Hertervig, Erik

Published
2023
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30. I-CARE, a European Prospective Cohort Study Assessing Safety and Effectiveness of Biologics in Inflammatory Bowel Disease

Author

Gornet, Jean-Marc, Beaugerie, Laurent, Shaji, Sebastian, Peyrin-Biroulet, Laurent, Reimund, Jean-Marie, Hebuterne, Xavier, Amiot, Aurélien, Armelao, Franco, Blanc, Pierre, Papi, Claudio, De Chambrun, Guillaume Pineton, Roblin, Xavier, Chu, Karmiris, Konstantinos, Shariq, Sohail, Viazis, Nikolaos, Limdi, Jimmy, Eder H, Piotr, Michalopoulos, Georgios, Bell, Andrew, Biancone, Livia, Dewitte, Marie, Mazhar, Zia, Franchimont, Denis, Nancey, Stephane, Macaigne, Gilles, Principi, Maria Beatrice, Fumery, Mathurin, Parkes, Gareth, Valats, Jean-Christophe, Doherty, Glen, Bouguen, Guillaume, Molnar, Tamás, Tsai, Hersin, Gangi, Mohsin, Pedersen, Natalia, Heluwaert, Frédéric, Shenderey, Richard, Zeissig, Sebastian, Butterworth, Jeffrey, Castiglione, Fabiana, Corless, Lynsey, Zallot, Camille, Baert, Filip, Singh, Salil, Sonwalkar, Sunil, Clayton, Elizabeth, Rahier, Jean-François, Vani, Deven, Bellaiche, Guy, De Vos, Martine, Kirchgesner, Julien, Kopylov, Uri, Lobaton, Triana, Locher, Christophe, Mantzaris, Gerassimos, Abouda, George, Smith, Katie, Sprakes, Michael, Theodoropoulou, Angeliki, Wesley, Emma, Bonnet, Joëlle, Elphick, David, Gilletta, Cyrielle, Gordon, John, Laharie, David, Nakad, Antoine, Orlando, Ambrogio, Dubois, Patrick, Hasselblatt, Peter, Michiels, Christophe, Preston, Cathryn, Staicu, Anca, Vuitton, Lucine, Kaassis, Mehdi, Speight, Ally, Ghosh, Deb, Löwenberg, Mark, Mathieu, Nicolas, Pelletier, Anne-Laure, Phillips, Anne, Magro, Fernando, Altwegg, Romain, Avni, Irit, biron, Landy, Jonathon, Nachury, Maria, Shenoy, Achuth, Trang, Caroline, Abitbol, Vered, Bamias, Georgios, Farkas, Klaudia, Maaser, Christian, Shitrit, Ariella, Siegmund, Britta, Filippi, Jérôme, O'morain, Colm, Yanai, Henit, Costes, Laurent, Hobday, David, Szepes, Zoltán, Calabrese, Emma, Dallal, Helen, Fung, Michael, Ramadas, Arvind, Baburajan, Bijay, Koss, Konrad, Barberis, Christophe, Buisson, Anthony, Amil, Morgane, Balestrieri, Paola, Johnson, Matthew, Tzouvala, Maria, Viennot, Stéphanie, Nagy, Ferenc, Thompson, Nick, Alric, Laurent, Samuel, Sunil, Bourrier, Anne, Chanteloup, Elise, Del Tedesco, Emilie, Harbord, Marcus, Lobo, Alan, Myers, Sally, Pollok, Richard, Ahmad, Tariq, Chaudhary, Rakesh, Karakoidas, Christos, Soliman, Ashraf, Stefanescu, Carmen, Theocharis, Georgios, Branden, Stijn Vanden, Beltran, Belén, Bouhnik, Yoram, Bourreille, Arnaud, Branco, Joana, Colleypriest, Ben, Eliakim, Rami, Knight, Paul, O'toole, Aoibhlinn, Robles, Virgina, Triantafyllou, Konstantinos, Bosca, Marta Maia, Lambrecht, Guy, Mosquera, Lucia Marquez, Panter, Simon, Pappa, Aikaterini, Simon, Marion, Sivaji, Ganesh, Bellanger, Christophe, Belle, Arthur, Borruel, Natalia, Egan, Laurence, Peeters, Harald, Sharpstone, Daniel, Arasaradnam, Ramesh, Benitez, José Manuel, Dahlerup, Jens Frederik, Giouleme, Olga, Gisbert, Javier P., Helwig, Ulf, Minguez, Miguel, Tsironi, Eftychia, Variola, Angela, Allen, Patrick, Boivineau, Lucille, Cole, Andy, Dib, Nina, Gomollon, Fernando, Johnston, Richard, Katsanos, Konstantinos, Kennedy, Nick, Kiszka-Kanowitz, Marianne, Marin-Jimenez, Ignacio, Miheller, Pál, Nos, Pilar, Saraj, Othman, Vinter-Jensen, Lars, Zittan, Eran, Baudry, Clotilde, Calvet, Xavier, Cazelles-Boudier, Marie-Christine, Coenegrachts, Jean-Louis, Cullen, Garret, Daperno, Marco, Dhar, Anjan, Gerard, Romain, Jensen, Nanna, Maharshak, Nitsan, Mcalindon, Mark, Mcloughlin, Simon, Parkes, Miles, Patel, Kamal, Peixoto, Armando, Polymeros, Dimitrios, Portela, Francisco, Rocca, Rodolfo, Seksik, Philippe, Subramanian, Sreedhar, Tennenbaum, Ruth, Atreya, Raja, Bachmann, Oliver, Berger, Arthur, Bor, Renáta, Buckley, Maire, Carpio, Daniel, Chaparro, María, Costa, Francesco, Domenech, Eugeni, Esteve, Maria, Foley, Stephen, Guardiola, Jordi, Koutroubakis, Ioannis, Kuehbacher, Tanja, Landman, Cécilia, Lavagna, Alessandro, Manceñido, Noemí, Mañosa, Míriam, Martín-Arranz, Maria Dolores, Plastaras, Laurianne, Scribano, Maria Lia, Sengupta, Subhasish, Teich, Nils, Tran-Minh, My-Linh, Zampeli, Evanthia, Amininejad, Leila, Arroyo, Teresa, Attar, Alain, Backman, Ann-Sofie, Bálint, Anita, Beckly, John, Ben Horin, Shomron, Bernardo, Sónia, Caillo, Ludovic, Caron, Bénédicte, Shanika de Silva, María, FábiáN, Anna, Fiorino, Gionata, Gutierrez, Ana, Lahat, Adi, Masmoudi, Mohamed, Mendolaro, Marco, Muls, Vinciane, Poullenot, Florian, Probert, Christopher, Reenaers, Catherine, Rutka, Mariann, Sarwari, Zaman, Sayer, Joanne, Sicilia, Beatriz, Sousa, Helena, van Kemseke, Catherine, Zabana, Yamile, Astegiano, Marco, Banim, Paul, Bettenworth, Dominik, Boualit, Médina, Brodersen, Jacob Broder, Christidou, Angeliki, Cooney, Rachel, Pinto, João Cortez, Cravo, Portugal Marília, Cremer, Anneline, Danese, Silvio, di Sabatino, Antonio, Fallingborg, Jan, Ferronato, Antonio, Planella, Esther Garcia, Gupta, Sanjay, Halfvarson, Jonas, Israeli, Eran, Kestenbaum, Samantha, Larsen, Lone, Macken, Elisabeth, Mathou, Nicoletta, Milassin, Ágnes, Pofelski, Joanna, Ricci, Chiara, Rodriguez-Moranta, Francisco, Schmidt-Lauber, Martin, Shaw, Ian, Soares, Marta, Soliman, Heithem, Triantos, Christos, Zografos, Konstantinos, Agrawal, Anurag, Armuzzi, Alessandro, Aubourg, Alexandre, Acosta, Manuel Barreiro-de, Barrio, Jesús, Bergemalm, Daniel, Bermejo, Fernando, Bodini, Giorgia, Bohr, Johan, Bossuyt, Peter, Christodoulou, Dimitrios, Claessens, Christophe, Collins, Paul, de Francisco, Ruth, Garcia, Santiago, Georgopoulos, Sotirios, Goutorbe, Felix, Kalantzis, Chrisostomos, Kourikou, Anastasia, Mace, Vincent, Malamut, Georgia, Ministro, Paula, Larmurier, Isabelle Nion, Ricart, Elena, Serrero, Mélanie, Sheridan, Juliette, Weimers, Petra, Andersen, Vibeke, Arroja, Bruno, Bokemeyer, Bernd, Bujanda, Luis, Degand, Thibault, Eriksson, Carl, Garceau, Cécile, Glerup, Henning, Goren, Idan, Jackson, Lucina, Koch, Stéphane, Mesonero, Francisco, Ordas, Ingrid, Riviere, Pauline, Saibeni, Simone, Soares, João, Tavernier, Noémie, Theede, Klaus, Ungar, Bella, Bästlein, Elke, Gasbarrini, Antonio, Protopapas, Andreas, Reindl, Wolfgang, Bossa, Fabrizio, Hart, Ailsa, Heil, Franz-Josef, O'Connor, Anthony, Oldenburg, Bas, Pastorelli, Luca, Stephen patchett, Ramakrishnan, Subramaniam, de Caestecker, John, Echarri, Ana, Kevans, David, Büning, Jürgen, Coelho, Rosa, Jansen, Jeroen, Koslowski, Benjamin, Wells, Christopher, Ceballos, Daniel, König, Ingrid, Padmanabhan, Hari, Patani, Timi, Qureshi, Raheel, Zagorowicz, Edyta, Allez, Matthieu, Archavlis, Emmanouil, Bonnet, Delphine, Guidi, Luisa, Mcnamara, Deirdre, Vernia, Piero, Weidenhiller, Michael, Alon, Lang, Boysen, Trine, Delattre, Charlotte, Farrell, Richard, Krüger, Rolf-Achim, Paupard, Thierry, Vind, Ida, Caprioli, Flavio, Gancho, Vladimir, Quentin, Vincent, Avidan, Benjamin, D’Haens, Geert, Mccarthy, Jane, Snook, Jonathon, Soufleris, Konstantinos, Zerbib, Frank, Carter, Dan, Depla, Annekatrien, Eisenbach, Thomas, Fries, Walter, Grammatikos, Nikolaos, Ilegems, Saskia, Lopez-Sanroman, Antonio, Moreau, Jacques, Riegler, Gabriele, Rietdijk, Svend, Rocha, Marta, Rosa, Isabelle, Ryan, Barbara, Yeremenko, Yelena, Boruchowicz, Arnaud, Damião, Filipe, Laoudi, Foteini, Lügering, Andreas, Macarri, Giampiero, Thomopoulos, Konstantinos, Barros, Luísa, Blixt, Thomas, Garros, Aurélien, Khorrami, Sam, Sokol, Harry, Sturm, Andreas, Livovsky, Dan, Maul, Jochen, Miks, Heinrich, Papadopoulos, Vasileios, Schmidt, Carsten, Snir, Yifat, Svenningsen, Lise, Ahmed, Wafaa, Broitman, Yelena, Cuillerier, Emmanuel, Kant, Prashant, Leyden, Jan, Lichtenstein, Lev, Lopes, Susana, Martineau, Chloé, Mulcahy, Hugh, Schweitzer, Axel, Van Schaik, Fiona, Banai, Hagar, Danion, Pauline, Dulery, Charlotte, Fidder, Herma, Gay, Claire, Hagege, Hervé, Harnois, Florence, Jørgensen, Søren Peter, Müller-Ziehm, Jens, Oikonomou, Michail, Palmela, Carolina, Schulze/Röske, Jörg, Smith, Mark, Thurm, Tamar, Bresso, Francesca, Brixi, Hedia, Jones, John, Macmathuna, Padraig, Painchart, Claire, Ron, Yulia, Vester-Andersen, Marianne, Alexandrino, Gonçalo, Börner, Norbert, Cardoso, Mariana, Chagas, Cristina, Dignaß, Axel, Dotan, Iris, Hedin, Charlotte, Karatzas, Pantelis, Kasapidis, Panagiotis, Palatka, Károly, Sakizlis, Georgios, Wilson, Ana, Bosanko, Nick, Caldeira, Paulo, Gagniere, Charlotte, Libier, Louise, Meunier, Camille, Moog, Gero, Pasquion, Audrey, Pica, Roberta, Akbar, Ayesha, Arab, Nadia, Cadiot, Guillaume, Carvalho, João, Charpignon, Claire, Fellermann, Laus, Fishman, Sigal, Fraser, Gerald, Gluck, Nathan, Hoesl, Mark, Kierkus, Jarosław, Klopocka, Maria, Arranz, Eduardo Martin, Menchen, Luis, Nikolaus, Susanna, Petrache, Anca, Ponsioen, Cyriel, Riestra, Sabino, Robledo, Pilar, Rodriguez, Cristina, Samer, Misheal, Tischer, Matthias, Wypych, Joanna, Baudon, Julien, Bezzio, Cristina, Boschetti, Gilles, Burisch, Johan, Creed, Tom, Demarzo, Maria Giulia, Festa, Stefano, Figueroa, Andrés, Julsgaard, Mette, Navarro, Pablo, Perez-Galindo, Pablo, Rouillon, Cléa, Sablich, Emanuele, Tosca, Joan, Vidon, Mathias, Vidon, Marine, Vitte, René-Louis, Wampach, Anne, Baumann, Cédric, Urmes, Isabelle Clerc, Rousseau, Hélène, Borie, Marc, Uzzan, Mathieu, Chatten, Kelly, Peter, Rimmer, Tariq, Iqbal, Cossignani, Marta, Cañete, Fiorella, Holvoet, Tom, Krasz, Susanne, Dias, Sandra, Abalia, Hadas, Abaza, Aziza, Abramovich, Gal, Ackzell, Ingrid, Adams, Carol, Addleton, Catherine, Alfambra, Erika, Algaba, Alicia, Allcock, Clare, Allison, Joanna, Amouriaux, Karine, Anderson, Julie, Anderson, Emma, Appelmans, Saskia, Armstrong, Lisa, Atkins, Stacey, Attaran-Bandarabadi, Masoumeh, Bailey, Yvonne, Bardot, Stephanie, Beck, Natasha, Bennett, Lillie, Bergfeld, Jonathan Phil, Berkane, Ramdane, Boey, Hanne, Bowlas, Louise, Bradley-Potts, Joanne, Brear, Tracy, Bretlander-Peters, Nicole, Brown, Ellen, Brown, Johanna, Buckingham, Elizabeth, Buellens, Katrien, Bull, Rhian, Burke, Maura, Burns, Leighanne, Burton, Julie, Bwalya, Agness, Cabanas, Karine, Callaghan, Muriel, Camou, Océane, Campbell, Debbie, Capoferro, Elvira, Carnahan, Mandy, Carnio, Cornelia, Carter, Anne, Clack, Concetta Casali, Chedouba, Leïla, Cipriano, Bessie, Claeys, Sophie, Closset, Manon, Coban, Dilek, Cococcia, Sara, Coe, Carolann, Cole, Helen, Collet, Emilie, Collins, Kayleigh, Combes, Isabelle, Connor, Emma, Constantin, Kathryn, Cooke, Susan, Cornet, Nathanaëlle, Corrihons, Estelle, Corsino, Pilar, Cortaville, Rosie, Cotterill, Donna, Cowton, Amanda, Cox, Harriet, Cripps, Viktoria, Crowder, Amanda, Cukier, Tzufit, Daniel, Amelia, Dawe, Chris, de Haan, Jose, Croix, Rosanna de la, Dejonckheere, Evva, Villanegro, Juan Delare, Delaval, Guillaume, Delliponti, Mariangela, Delommez, Aude, Detry, Emilie, Dhanaratne, Melanie, Galan, Laura Diez, Dodel, Marie, Dooks, Emma, Du Cheyron, Joseph, Duane, Linda, Vulgo Cochran, Jennifer Dulling, Dyer, Simona, Dymond, Harvey, Ekblad, Charlotte, Elliott, Kerry, Emmerson, Ingrid, Eugene-Jolchine, Irène, Fleming, Lorna, Fletcher, Eve, Ford, Sarah, Forshaw, Greg, Foulds, Angela, Francois, Caroline, Fuge, Nicole, Gafni, Gal, Ganon, Miri, Nuñez, Olga Garcia, Ramirez, Laura Garcia, Gelder, Sophie, Gettkowski, Raimonda, Gilardi, Daniela, Giuffrida, Paolo, Gobert, Vincent, Godden, Jo, Godwin, Nuala, Goulden, Kay, Graham, Sharon, Green, Charlotte, Green, Marie, Gueye, Aboubakar, Guler, Tuba, Gustavsson, Ida, Hadjisavvas, Helena, Hammonds, Fiona, Hantzi, Christina, Hauke, Marion, Haydock, Julie, Hayes, Orla, Nislev, Lizette Helbo, Hochstodter, Jessica, Hogg, Ashleigh, Hölbing, Manuela, Holland, Maureen, Holsbergen, Maartje, Howard, Linda, Hoyda, Aviya, Hull, Robert, Irish, Jane, Jackson, Wendy, Janssen, Wendy, Jeffrey, Lesley, Jourdan, Sofia, Jutrowska, Izabela, Kaniel, Chava, Karezos, Theofilos, Kelly, Niamh, Kelly, Jessica, Kennedy, Mary, Kennedy, Una, Kibaru, Joyce, Kirkman, Gemma, Klaproth, Janine, Kneese, Corinna, Koch, Andrea, Kokke, Kathleen, Koppelow, Martha, Krause, Sabine, Krauspe, Sabine, Kwakkenbos, Petra, Labarile, Nunzia, Lang, Hannah, Lassailly, Marianne, Leconte, Martine, Lepczynski, Linda, Levell, Emma, Levhar, Nina, Lindhort, Kerstin, Lisle, Jessica, Cauce, Beatriz Lopez, Lorenz, Gabriele, Lovati, Ambra, Lowry, Tracey, Lund, Margareta, Vorderbrügge, Anne Lutz, Maansson, Suzanne, Madapathage, Videsheka, Cheviakoff, Maelys, Magness, Alison, Manley, Orla, Manyoni, Catherine, Marg, Ingke, Marra, Antonella, Martins, Carole, Massella, Arianna, Mathias, Aurore, Mervyn, Danielle, Minsart, Charlotte, Mitchell, Sally, Monks, Kathleen, Montero, Mélanie, Moore, Alson, Moser, Maren, Moss, Alison, Mullen, Angela, Murciano, M. Francisca, Naylor, Deanna, Nehus, Ansgar, Nicholson, Anne, Nöding, Sarah, Nolan, Sinead, Nörenberg, Janet, Northcott, Clare, O'Connell, Jim, O’Kelly, Alison, Orbach-Zingboim, Noam, Orobitg, Judit, Otieno, Charlene, Owen, Charlotte, Patch, Sarah, Pauker, Maor, Pauli, Renate, Pearson, Harriet, Peggy, Falgon, Petit, Séverine, Petrissans, Christine, Piergallini, Simona, Pippard, Lucy, Pitt, Laura, Pócsik, Gabriella, Poher, Yoann, Pomes, Chloé, Pritchard, Lucy, Puchades, Laura, Quaid, Sheena, Rana, Aleem, Raynard, Dana, Reilly, Mykla, Reinert, Sonja, Reinknecht, Manuela, Renner, Baerbel, Reynolds, Rob, Rizzuto, Giulia, Robinson, Matthew, Robrechts, Joke, Rodriguez, Eva M., Rosenblum, Efrat, Russel, Tamlyn, Sadare, Ibiyemi, Salama, Noa, Schakel, Toos, Schauer, Anja, Schiavoni, Elisa, Shaw, Caroline, Shelton, Sarah, Sicart, Virginie, Siouville, Elodie, Smith, Orla, Soude, Théo, Stephenson, Sophie, Stephenson, Elaine, Steppe, Marjan, Sterkx, An, Stickley, Jo, Sugrue, Kathleen, Swietec, Natalia, Tasiaux, Charlotte, Thamu, Bhavneet, Thomas, Susane, Tobi, Ogwa, Touabi, Kahina, Tovi, Shifra, Tregonning, Julie, Turchini, Laura, Unkhoff, Julia, Unruh, Olesya, Uzun, Nurcan, Van Aert, Frauke, Bergh, Sandrine Vanden, Vandenbroucke, Louise, Vansteenkiste, Laura, Vardit, Shay, Vergriete, Valentin, Walker, Elaine, Warner, Eleanor, Watchorn, Olivia, Watson, Ekaterina, Wauthier, Marie-Claire, Weetman, Belgium Maria, Weston, Margaret, West-Petroschka, Wiebke, Wienecke, Susann, Wierling, Kerstin, Wiestler, Miriam, Wilcox, Rebecca, Wilhelmsen, Elva, Williams, Angharad, Williamson, Georgina, Wilson, Deborah, Wistance, Kate, Wortmann, Nicolas, Wurie, Subie, Yadgar, Karin, Young, Gail, Young, Megan, Aucouturier, Julien, Bertin, Marie- Jo, Bougrine, Hasnae, Coisnon, Marie, Defrance, Antoine, Gutierrez, Kati, Harouz, Amel, Jerber, Laure, Khlifi, Aida, Kirati, Amina, Liworo, Nasaladjine, Logoltat, Maude, Mailhat, Charlotte, M'Bayi, Chancely, Medane, Yasmina, Merkhoufa, Dalal, Elhad, Saouda Mohamed, Monthe, Bertille, Moyon, Fanny, Rabiega, Pascaline, Sekela, Jennifer, Thilloy, Charlotte, Hamamouche, Naima, Partisotti, Frederic, Blandin, Patrick, Mokhtari, Hocine, Coutard, Laure, and Doherty, Glen A.

Published
2023
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33. Nested Bandits.

Author

Matthieu Martin, Panayotis Mertikopoulos, Thibaud Rahier, and Houssam Zenati

Published
2022

40. Kidney function monitoring in inflammatory bowel disease: The MONITORED consensus

Author

Guillo, Lucas, Delanaye, Pierre, Flamant, Martin, Figueres, Lucile, Karam, Sabine, Lemoine, Sandrine, Benezech, Alban, Pelletier, Anne-Laure, Amiot, Aurélien, Caron, Bénédicte, Stefanescu, Carmen, Boschetti, Gilles, Bouguen, Guillaume, Rahier, Jean-François, Gornet, Jean-Marc, Hugot, Jean-Pierre, Bonnet, Joëlle, Vuitton, Lucine, Nachury, Maria, Vidon, Mathias, Uzzan, Mathieu, Serrero, Mélanie, Dib, Nina, Seksik, Philippe, Hebuterne, Xavier, Bertocchio, Jean-Philippe, Mariat, Christophe, and Peyrin-Biroulet, Laurent

Published
2022
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42. Crystallization of Amorphous N‐Doped Ge‐Rich GST Layers Deposited on a Polycrystalline GST Template.

Author

Luong, Minh‐Anh, Rahier, Eloïse, Ran, Sijia, and Claverie, Alain

Subjects
*TRANSMISSION electron microscopes, *SCANNING electron microscopes, *ANALYTICAL chemistry, *PHASE separation, *CRYSTALLIZATION
Abstract

Herein, a detailed experimental study of the crystallization of amorphous N‐doped Ge‐rich GeSbTe layers (GGSTN) when in contact with a polycrystalline GeSbTe (GST template is reported on. By combining in situ annealing in the transmission electron microscope and ex situ chemical analysis, it is shown that, as observed in many materials, the layer in contact with the crystalline template crystallizes at a lower temperature than needed for bulk crystallization. At surprise, this characteristic is not due to the solid‐phase epitaxy of the GGSTN on the crystalline GST template but to a decrease of the Ge content in the GGSTN layer. Indeed, during annealing, Ge diffuses from the amorphous layer into the crystalline GST layer where it gets trapped and forms grains which grow, eventually leading to the formation of a pure crystalline Ge layer. As a result of this Ge depletion, the thermal budget necessary to drive the phase separation limiting the crystallization of the remaining GGSTN alloy is smaller. [ABSTRACT FROM AUTHOR]

Published
2024
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43. The Influence of the Thermal Treatment of Copper Slag on the Microstructure and Performance of Phosphate Cements

Author

Rania Derouiche, Patrick Ninla Lemougna, Guillermo Meza Hernandez, Jun Gu, Samir Baklouti, and Hubert Rahier

Subjects
copper slag, thermal treatment, fayalite, acid-activated, phosphate cement, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, QC120-168.85
Abstract

In general, phosphate cements have a very rapid setting reaction at room temperature. The same holds for copper slag-based phosphate cements. This means that using them as a binder, for instance as mortar, is always possible on a small scale, but very difficult on a large scale. In this paper, the heat treatment of the copper slag was shown to be an effective way to increase the setting time and keep the mix workable for an adequate period. The main objective of this research was to examine the changes in the phase composition of quenched copper slag after exposure to 500 °C and to evaluate the impact of these changes on the reactivity of the material in an acidic environment, as well as on the mechanical properties, microstructure, and structure of the produced phosphate cement materials. Various experimental methods were utilized to characterize the raw materials and the obtained phosphate cementitious materials, including isothermal microcalorimetry (TAM Air), thermogravimetric analysis (TGA), infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), as well as the determination of the chemical composition using X-ray fluorescence (XRF) and the particle size distribution. Furthermore, compressive strength tests were conducted to gauge the mechanical resistance of the materials. The main findings of this work revealed that subjecting the copper slag to a thermal treatment of 500 °C induced a partial transformation in its structure. The high temperature caused the oxidation of some of the divalent iron oxide in the slag, leading to the formation of hematite. This treatment increased the setting time and reduced the reactivity of the copper slag with phosphoric acid, ultimately enabling the production of a dense phosphate-based cementitious material with outstanding mechanical properties. The compressive strength of the newly developed cement was recorded to be greater than 78.9 MPa after 7 days, and this strength continued to increase, reaching 82.5 MPa after 28 days.

Published
2023
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47. I/O Post- and Co-Processing for High-Order Methods

Author

Rasquin, M., Hillewaert, K., Bassi, F., Colombo, A., Massa, F., Rahier, G., Martin, E., Renac, F., Hirschel, Ernst Heinrich, Founding Editor, Schröder, Wolfgang, Series Editor, Boersma, Bendiks Jan, Editorial Board Member, Fujii, Kozo, Editorial Board Member, Haase, Werner, Editorial Board Member, Leschziner, Michael A., Editorial Board Member, Periaux, Jacques, Editorial Board Member, Pirozzoli, Sergio, Editorial Board Member, Rizzi, Arthur, Editorial Board Member, Roux, Bernard, Editorial Board Member, Shokin, Yurii I., Editorial Board Member, Mäteling, Esther, Managing Editor, Hirsch, Charles, editor, Hillewaert, Koen, editor, Hartmann, Ralf, editor, Couaillier, Vincent, editor, Boussuge, Jean-Francois, editor, Chalot, Frederic, editor, and Bosniakov, Sergey, editor

Published
2021
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