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See detailAn Extended Flexible Job Shop Scheduling Problem with Parallel Operations
Tessaro Lunardi, Willian UL; Voos, Holger UL

in ACM SIGAPP Applied Computing Review (2018), 18(2), 46-56

Traditional planning and scheduling techniques still hold important roles in modern smart scheduling systems. Realistic features present in modern manufacturing systems need to be incorporated into these ... [more ▼]

Traditional planning and scheduling techniques still hold important roles in modern smart scheduling systems. Realistic features present in modern manufacturing systems need to be incorporated into these techniques. Flexible job-shop scheduling problem (FJSP) is one of the most challenging combinatorial optimization problems. FJSP is an extension of the classical job shop scheduling problem where an operation can be processed by several different machines. In this paper, we consider the FJSP with parallel operations (EFJSP) and we propose and compare a discrete firefly algorithm (FA) and a genetic algorithm (GA) for the problem. Several FJSP and EFJSP instances were used to evaluate the performance of the proposed algorithms. Comparisons among our methods and state-of-the-art algorithms are also provided. The experimental results demonstrate that the FA and GA achieved improvements in terms of efficiency and efficacy. Solutions obtained by both algorithms are comparable to those obtained by algorithms with local search. In addition, based on our initial experiments, results show that the proposed discrete firefly algorithm is feasible, more effective and efficient than our proposed genetic algorithm for the considered problem. [less ▲]

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See detailApplication of Value Stream Management to enhance product and information flows in supply chain networks - based on the example of web-based automotive retail business
Plapper, Peter UL; Oberhausen, Christof UL; Minoufekr, Meysam UL

in Management and Production Engineering Review (2018), 9(2), 13-19

Due to globalized business operations, companies in different economic sectors are part of complex supply chain networks. Their value-added processes comprise product and information flows, e.g. with a ... [more ▼]

Due to globalized business operations, companies in different economic sectors are part of complex supply chain networks. Their value-added processes comprise product and information flows, e.g. with a focus on manufacturing, service or trade. Until the final product is delivered to the end customer, it needs to pass many different processes in cooperating organizations. As a result, there a lot of business-to-business (B2B) interactions with cross-enterprise transactions, often including cross-border communications and sometimes even cross-industry trades with technological and often cultural implications. Especially the interfaces of supply chain networks are prone to inefficiencies, misunderstandings and delays due to a lack of standardized B2B transactions, which leads to waste in form of rework, errors and mistakes. In addition, new customers are hard to find for the manufacturing or trading company, since potential customers are so far limited to a regional network. The advantages of extending the customer base still need to be explored by many organizations. This paper discusses the opportunities by streamlining the communication along supply chain networks in a general fashion and then describes the application in a B2B automotive retail business. A concept of a web-based trading platform, which provides a seamless service for all steps of a convenient and efficient used vehicle remarketing business, is developed. It includes all phases, like offering and price finding in a comprehensive online platform, which also covers further activities, such as logistic services, financial transactions, and a mandatory feedback loop. The suggested B2B vehicle-trading platform enables a quick turnover of each transaction, which is analyzed and optimized based on the application of cross-enterprise Value Stream Management. [less ▲]

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See detailTask interference and distraction efficacy in patients with fibromyalgia: an experimental investigation
van Ryckeghem, Dimitri UL; Rost, Silke; Kissi, Ama et al

in Pain (2018), 159(6), 1119-1126

Pain has the capacity to interfere with daily tasks. Although task interference by pain is largely unintentional, it can be controlled to a certain extent. Such top-down control over pain has been thought ... [more ▼]

Pain has the capacity to interfere with daily tasks. Although task interference by pain is largely unintentional, it can be controlled to a certain extent. Such top-down control over pain has been thought to be reduced in fibromyalgia patients. In this study, we investigated task interference and distraction efficacy in fibromyalgia patients (FM) and a matched healthy control group. Forty-nine fibromyalgia patients and 49 heathy volunteers performed as quickly as possible (a) a visual localization task in the presence of non-painful vibrating or painful electric somatic stimuli, and (b) a somatosensory localization task (using non-painful or painful stimuli). Participants reported on their experience of the somatic stimuli on some of the trials during both localisation tasks. Results indicated that pain interferes with performance of the visual task, in both FM patients and healthy individuals. Furthermore, participants experienced the pain stimulus as less intense when directing attention away from the pain than when focusing on the pain. Overall, task performance of FM patients was slower compared to the task performance in the healthy control group. In contrast to our hypotheses, FM patients and healthy volunteers did not differ in the magnitude of the interference effect and distraction-efficacy. In conclusion, current study provides support for contemporary theories claiming that attention modulates the experience of pain and vice versa. However, no evidence was however found for an altered attentional processing of pain in fibromyalgia patients. Furthermore, results indicate that task interference and distraction-efficacy are not just two sides of the same coin. [less ▲]

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See detailLe changement de rôle des patients de maladie Chronique dans l'organisation des soins
Odero, Angela UL; Bucki, Barbara; Baumann, Michèle UL

in Pratiques et interventions en santé (2018, June)

Introduction: Les patients sont de plus en plus impliqués dans les soins qui exigent leur engagement dans la surveillance, la prévention des risques, l'auto-éducation et l'auto-traitement. Les ... [more ▼]

Introduction: Les patients sont de plus en plus impliqués dans les soins qui exigent leur engagement dans la surveillance, la prévention des risques, l'auto-éducation et l'auto-traitement. Les professionnels, quant à eux, ils sont plus enclins à adopter avec leurs patients des modèles d'interaction équitable. Sur le plan théorique, une Approche Patient Partenaire de Soins (APPS) a été proposée par des chercheurs canadiens. Pour clarifier ce que représente l’APPS, une étude qualitative a tenté d’analyser les facteurs culturels et psychosociaux qui interviennent dans la mise en place d’une APPS. Méthode : Avec l’appui des associations luxembourgeoises, six focus groupes ont été organisés avec 30 patients. A partir des retranscriptions, une analyse de contenu thématique catégorielle a été réalisée avec l’aide de N’Vivo 12 Résultats: Parmi les obstacles qui freinent une APPS, des divergences culturelles entre patients et professionnels de santé sont évoqués. Des patients préfèrent en effet rester en harmonie avec leurs valeurs et refusent de partager les prises de décision, pour eux seuls les professionnels doivent les prendre. Les échanges avec les professionnels restent compliqués car des positions dominantes et autoritaires demeurent. Parmi les facteurs favorisants APPS, on peut retenir le fait que les patients estiment avoir une connaissance de leur corps, et qu’ils ressentent l’impact que peut avoir les effets secondaires des traitements ; ceci à condition qu’ils soient capables de les verbaliser. Enfin l'accent est mis sur une confiance réciproque. Conclusion: Une éducation des patients devrait être développée pour leur permettre d’acquérir un «Capital Culturel en Santé» ; une connaissance de base favorisant la compréhension des soins et facilitant les relations avec les professionnels de santé. De même, une formation médicale et une pratique infirmière plus soutenues par des «Compétences Culturelles» permettaient aux professionnels de mieux reconnaître l'impact socioculturel que peut avoir leur identité lors de leurs relations avec les patients. [less ▲]

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See detailDer Raum ist kein empirischer Begriff. Zu Kants erstem Raumargument
Heidemann, Dietmar UL

in CON-TEXTOS KANTIANOS. International Journal of Philosophy (2018), 7

„The paper discusses Kant’s first argument from space in the „Critique of pure Reason”. It argues that, contrary to what parts of the literature have claimed, the argument provides convincing reasons for ... [more ▼]

„The paper discusses Kant’s first argument from space in the „Critique of pure Reason”. It argues that, contrary to what parts of the literature have claimed, the argument provides convincing reasons for the view that in order to locate objects in space outside us we must already presuppose the idea of space such that it cannot be borrowed from the objects perceived in space. The paper shows how the argument can be made transparent not only by clarifying Kant’s usage of “distinct from” and “ausser uns” but also by retracing its main idea back to the 1768 essay “Concerning the Ultimate Foundation of the Differentiation of Regions in Space” and its incongruent counterparts argument. [less ▲]

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See detailEventually everything connects
Lallemand, Carine UL

Speeches/Talks (2018)

If you are reading these lines, you are probably curious about the type of experience that you would have as an attendee of this talk. You might wonder whether the topic would match your interests ... [more ▼]

If you are reading these lines, you are probably curious about the type of experience that you would have as an attendee of this talk. You might wonder whether the topic would match your interests, whether the speaker will be good enough to satisfy your expectations, whether you will feel inspired, exhilarated, or whether you will have concrete tools to bring back to your work. While you are usually the ones shaping people’s experiences, you are striving for nice experiences as well. Designing for human experiences is one of the most challenging yet fascinating activities. It is a responsibility that we should embrace with humility and dedication. To face the complexity of our mission, we need to draw on theoretical knowledge, methodological skills and of course on our shared professional expertise, as a community. While UX practitioners are working hard at the front lines to design better products or services, scientists work in the shadows to develop and consolidate a myriad of novel and highly valuable UX methods. During this talk, you will discover the ever-growing UX toolbox that could greatly support you in collecting richer, insightful and more valid data. From scientific theories to pragmatic methods, from academia to industry, from Luxembourg to Puerto Rico… Eventually everything connects. [less ▲]

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See detailExperience report: How to extract security protocols’ specifications from C libraries
Vazquez Sandoval, Itzel UL; Lenzini, Gabriele UL

in 2018 IEEE 42nd Annual Computer Software and Applications Conference (COMPSAC) (2018, June)

Often, analysts have to face a challenging situation when formally verifying the implementation of a security protocol: they need to build a model of the protocol from only poorly or not documented code ... [more ▼]

Often, analysts have to face a challenging situation when formally verifying the implementation of a security protocol: they need to build a model of the protocol from only poorly or not documented code, and with little or no help from the developers to better understand it. Security protocols implementations frequently use services provided by libraries coded in the C programming language; automatic tools for codelevel reverse engineering offer good support to comprehend the behavior of code in object-oriented languages but are ineffective to deal with libraries in C. Here we propose a systematic, yet human-dependent approach, which combines the capabilities of state-of-the-art tools in order to help the analyst to retrieve, step by step, the security protocol specifications from a library in C. Those specifications can then be used to create the formal model needed to carry out the analysis. [less ▲]

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See detailA Mathematical Model and a Firefly Algorithm for an Extended Flexible Job Shop Problem with Availability Constraints
Tessaro Lunardi, Willian UL; Cherri, Luiz Henrique; Voos, Holger UL

in 17th International Conference on Artificial Intelligence and Soft Computing, Zakopane, Poland, June 3-7, 2018 (2018, June)

Manufacturing scheduling strategies have historically ignored the availability of the machines. The more realistic the schedule, more accurate the calculations and predictions. Availability of machines ... [more ▼]

Manufacturing scheduling strategies have historically ignored the availability of the machines. The more realistic the schedule, more accurate the calculations and predictions. Availability of machines will play a crucial role in the Industry 4.0 smart factories. In this paper, a mixed integer linear programming model (MILP) and a discrete firefly algorithm (DFA) are proposed for an extended multi-objective FJSP with availability constraints (FJSP-FCR). Several standard instances of FJSP have been used to evaluate the performance of the model and the algorithm. New FJSP-FCR instances are provided. Comparisons among the proposed methods and other state-of-the-art reported algorithms are also presented. Alongside the proposed MILP model, a Genetic Algorithm is implemented for the experiments with the DFA. Extensive investigations are conducted to test the performance of the proposed model and the DFA. The comparisons between DFA and other recently published algorithms shows that it is a feasible approach for the stated problem. [less ▲]

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See detailQuantum tunneling of thermal protons through pristine graphene
Poltavskyi, Igor UL; Tkatchenko, Alexandre UL; Mortazavi, Majid et al

in Journal of Chemical Physics (2018), 148(20), 204707

Engineering of atomically thin membranes for hydrogen isotope separation is an actual challenge which has a broad range of applications. Recent experiments [M. Lozada-Hidalgo et al., Science 351, 68 (2016 ... [more ▼]

Engineering of atomically thin membranes for hydrogen isotope separation is an actual challenge which has a broad range of applications. Recent experiments [M. Lozada-Hidalgo et al., Science 351, 68 (2016)] unambiguously demonstrate an order-of-magnitude difference in permeabilities of graphene-based membranes to protons and deuterons at ambient conditions, making such materials promising for novel separation technologies. Here we demonstrate that the permeability mechanism in such systems changes from quantum tunneling for protons to quasi-classical transport for heavier isotopes. Quantum nuclear effects exhibit large temperature and mass dependence, modifying the Arrhenius activation energy and Arrhenius prefactor for protons by more than 0.5 eV and by seven orders of magnitude correspondingly. Our findings not only shed light on the separation process for hydrogen isotope ions passing through pristine graphene but also offer new insights for controlling ion transport mechanisms in nanostructured separation membranes by manipulating the shape of the barrier and transport process conditions. [less ▲]

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See detailAdvanced Raman Spectroscopy of Ultrathin RNiO3 films
Schober, Alexander UL

Doctoral thesis (2018)

The present work aims at investigating the structural properties of ultrathin rare-earth nickelate films by Raman Spectroscopy. Two remarkable cases are studied: LaNiO3 deposited epitaxially on LaAlO3 ... [more ▼]

The present work aims at investigating the structural properties of ultrathin rare-earth nickelate films by Raman Spectroscopy. Two remarkable cases are studied: LaNiO3 deposited epitaxially on LaAlO3, which shows a metal-to-insulator (MIT) transition but only in the ultrathin film regime, and NdNiO3 deposited epitaxially on NdGaO3 showing an upward shift of its MIT temperature by 130 K but only when deposited along the [111]pc direction of the substrate. The extremely small size of the films and overlap of the film and substrate signatures represent an experimental challenge and require the development of ingenious measurement and analysis strategies. To overcome these limitations, we propose the creation of a multidimensional dataset through depth profile acquisitions, in combination with multivariate analysis tools that were employed to extract the signature of the films. Different analysis strategies were used in both cases to adapt to the specificities of the respective samples. For the LNO films deposited along the [001]pc orientation of LAO, Raman depth profile measurements in combination with a Principal Component Analysis (PCA) allowed us to dissociate the signals from the film and the substrate. The evolution of the LNO peaks does not suggest any phase transition, thus, suggesting that a mechanism unrelated to the MIT of other nickelates is triggering the insulating state. This was further validated by ab initio calculations and TEM imaging. All acquired data point towards the following: as LNO becomes very thin, the surface layer (≈ 2pc u.c.), which is the most rigid part of the structure, imposes its structural and insulating characteristic. In the ultrathin regime this continues to a point where the surface of the film alters the interfacial unit cells of the substrate. For the NNO films deposited along the [111]pc orientation of NGO, depth profile measurements in combination with a Non-negative Matrix Factorisation (NMF) allowed us to dissociate the signals from the film and the substrate. The dissociation was performed at room temperature and the acquired knowledge was then utilised to fit an entire temperature series from 5 to 390 K. Comparing the tendency of the Raman signatures with other rare-earth nickelate allowed to support the proposed position of the film in the phase diagram of nickelates by a structural measurement. More generally, the methodology developed in this work is applicable to other systems and opens new perspectives for application of Raman spectroscopy on ultra-thin films. [less ▲]

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See detailKey-Skeleton Based Feedback Tool for Assisting Physical Activity
Baptista, Renato UL; Ghorbel, Enjie UL; Shabayek, Abd El Rahman UL et al

in 2018 Zooming Innovation in Consumer Electronics International Conference (ZINC), 30-31 May 2018 (2018, May 31)

This paper presents an intuitive feedback tool able to implicitly guide motion with respect to a reference movement. Such a tool is important in multiple applications requiring assisting physical ... [more ▼]

This paper presents an intuitive feedback tool able to implicitly guide motion with respect to a reference movement. Such a tool is important in multiple applications requiring assisting physical activities as in sports or rehabilitation. Our proposed approach is based on detecting key skeleton frames from a reference sequence of skeletons. The feedback is based on the 3D geometry analysis of the skeletons by taking into account the key-skeletons. Finally, the feedback is illustrated by a color-coded tool, which reflects the motion accuracy. [less ▲]

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See detailAssociative, idempotent, symmetric, and order-preserving operations on chains
Devillet, Jimmy UL; Teheux, Bruno UL

E-print/Working paper (2018)

We characterize the associative, idempotent, symmetric, and order-preserving operations on (finite) chains in terms of properties of (the Hasse diagram of) their associated semilattice order. In ... [more ▼]

We characterize the associative, idempotent, symmetric, and order-preserving operations on (finite) chains in terms of properties of (the Hasse diagram of) their associated semilattice order. In particular, we prove that the number of associative, idempotent, symmetric, and order-preserving operations on an n-element chain is the nth Catalan number. [less ▲]

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See detailBlunted endocrine response to a combined physical-cognitive stressor in adults with early life adversity
Hengesch, X.; Elwenspoek, M.M.C.; Schaan, Violetta UL et al

in Child Abuse & Neglect (2018)

The negative health effects of early life adversity (ELA) continue long into adulthood. Changes in the physiological response to psychosocial stressors have been proposed to mediate this effect. However ... [more ▼]

The negative health effects of early life adversity (ELA) continue long into adulthood. Changes in the physiological response to psychosocial stressors have been proposed to mediate this effect. However, many previous studies have come to contradicting conclusions as to whether ELA induces a long-term increase or decrease in stress reactivity. Therefore, we tested the association of ELA exposure and adult stress reactivity in a sample of early life adoptees and controls.Two previously validated stressful elements (bilateral feet CPT and the Paced Auditory Serial Addition Task (PASAT)) were combined in an extended Cold Pressor Test (CPT). This test was performed on 22 participants who had experienced severe ELA (separation from biological parents, institutionalization, and adoption in early childhood), and in 22 age-matched control participants.A prior history of ELA was associated with blunted reactivity of the hypothalamic-pituitary-adrenal (HPA) axis (Cohen´s d = 0.680). Cardiovascular reactivity remained unchanged, and affective reactivity (self-report ratings) were increased in participants exposed to ELA compared to the control group (range Cohen´s d: 0.642–0.879).Our results suggest that the activity of the HPA axis reactivity was inhibited in ELA participants. Importantly, cardiovascular stress responsiveness was not affected by ELA. This separation of the HPA axis and cardiovascular stress responses may best be explained by ELA selectively enhancing central feedback-sensitivity to glucocorticoids, but preserving cardiovascular/ autonomic stress reactivity. [less ▲]

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See detailEuropean institutions and european enterprises
Paravantis, Spero UL

Presentation (2018, May 30)

Seminar on "European institutions and European enterprises" (Seminar at Catholic University of the Sacred Heart, Milan, Italy, May 30 2018. From 01:00 to 24:00. I explain the Origins of the Rules ... [more ▼]

Seminar on "European institutions and European enterprises" (Seminar at Catholic University of the Sacred Heart, Milan, Italy, May 30 2018. From 01:00 to 24:00. I explain the Origins of the Rules surrounding the freedom of establishment in the EU. NOTE: the computer crashed before the seminar, so I had to look to the large screen to my left to read the notes. This is why I am looking left throughout the video.) [less ▲]

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See detailJugendliche mit erhöhtem Förderbedarf in den Projekten von Erasmus+: Jugend in Aktion - Beschreibung und Effekte
Meyers, Christiane UL; Mayerl, Martin

Conference given outside the academic context (2018)

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See detailSTUDY OF THE INCORPORATION MECHANISMS OF ORGANIC CHEMICALS INTO HAIR
Chata, Caroline Georgette Samia UL

Doctoral thesis (2018)

Hair presents several advantages for biomonitoring the exposure to pollutants. For instance, this matrix is representative of the mid to long term exposure depending on the length of the sample. However ... [more ▼]

Hair presents several advantages for biomonitoring the exposure to pollutants. For instance, this matrix is representative of the mid to long term exposure depending on the length of the sample. However the question concerning the hair incorporation mechanism of chemicals remain partially unravelled. The subject of the present PhD was the “study of the incorporation mechanisms of organic chemicals into hair” (StICHa). Therefore we focused on the influence of biological and physicochemical parameters on the incorporation of pesticides into hair. The results presented in the project were obtained from three experiments whose two animal experiments conducted on rats. The first one allowed to link levels of exposure of pesticides to the corresponding concentrations in plasma and in hair. This also allowed to study the accumulation of pesticides in the rat body over time and to investigate the influence of the pesticide physicochemical properties on their incorporation into hair. The second one provided pharmacokinetic (PK) parameters of pesticides in blood after a single exposure and highlighted the concept of background exposure corresponding to the detectable chemicals concentration in the animals before exposure due to environmental contamination. An in vitro test was also conducted to investigate bonds between pesticides and blood components and their influence on hair incorporation. [less ▲]

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See detailHigh‐performance low bandgap thin film solar cells for tandem applications
Elanzeery, Hossam UL; Babbe, Finn UL; Melchiorre, Michele UL et al

in Progress in Photovoltaics (2018)

Thin film tandem solar cells provide a promising approach to achieve high efficiencies. These tandem cells require at least a bottom low bandgap and an upper high bandgap solar cell. In this contribution ... [more ▼]

Thin film tandem solar cells provide a promising approach to achieve high efficiencies. These tandem cells require at least a bottom low bandgap and an upper high bandgap solar cell. In this contribution, 2 high‐performance Cu(In,Ga)Se2 cells with bandgaps as low as 1.04 and 1.07 eV are presented. These cells have shown certified efficiencies of 15.7% and 16.6% respectively. Measuring these cells under a 780‐nm longpass filter, corresponding to the bandgap of a typical top cell in tandem applications (1.57 eV), they achieved efficiencies of 7.9% and 8.3%. Admittance measurements showed no recombination active deep defects. One additional high‐performance CuInSe2 thin film solar cell with bandgap of 0.95 eV and efficiency of 14.1% is presented. All 3 cells have the potential to be integrated as bottom low bandgap cells in thin film tandem applications achieving efficiencies around 24% stacked with an efficient high bandgap top cell. [less ▲]

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See detailIdentifying the Cognitive Mechanism Behind Breaks in Presence using Measures of Attention
Holl, Elisabeth UL; Huber, Kerstin; Liebold, Benny et al

Scientific Conference (2018, May 28)

Presence is the perceptual illusion of non-mediation in virtual environments with breaks in presence (BIPs) marking events where the user’s attention is shifted away from the virtual to the physical ... [more ▼]

Presence is the perceptual illusion of non-mediation in virtual environments with breaks in presence (BIPs) marking events where the user’s attention is shifted away from the virtual to the physical environment. Using the concept of BIP allows to investigate specific episodes during virtual encounters, where the state of presence is interrupted. Orienting responses have been identified as a promising cognitive mechanism behind BIPs. However, the differences of orienting to narrative stimuli versus BIPs remains to be investigated. In the current study, we combined established psychophysiological measures of orienting (ECG, GSR) with psychophysiological (pupil dilation) and behavioral measures (STRT) of attention. BIPs are considered to elicit stronger orienting responses and require more cognitive resources. In an experiment, participants navigated through a virtual environment while having to react to narrative and external (BIPs) stimuli. While the data collection has been completed, results from the analysis will be discussed at the conference. [less ▲]

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