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See detailTOrPEDO: Witnessing Model Correctness with Topological Proofs
Menghi, Claudio UL; Rizzi, Alessandro Maria; Bernasconi, Anna et al

in Formal Aspects of Computing (in press)

Model design is not a linear, one-shot process. It proceeds through refinements and revisions. To effectively support developers in generating model refinements and revisions, it is desirable to have some ... [more ▼]

Model design is not a linear, one-shot process. It proceeds through refinements and revisions. To effectively support developers in generating model refinements and revisions, it is desirable to have some automated-support to verify evolvable models. To address this problem, we recently proposed to adopt topological proofs, which are slices of the original model that witness property satisfaction. We implemented TOrPEDO, a framework that provides automated support for using topological proofs during model design. Our results showed that topological proofs are significantly smaller than the original models, and that, in most of the cases, they allow the property to be re-verified by relying only on a simple syntactic check. However, our results also show that the procedure that computes topological proofs, which requires extracting unsatisfiable cores of LTL formulae, is computationally expensive. For this reason, TOrPEDO currently handles models with a small dimension. With the intent of providing practical and efficient support for flexible model design and wider adoption of our framework, in this paper, we propose an enhanced – re-engineered – version of TOrPEDO. The new version of TOrPEDO relies on a novel procedure to extract topological proofs, which has so far represented the bottleneck of TOrPEDO performances. We implemented our procedure within TOrPEDO by considering Partial Kripke Structures (PKSs) and Linear-time Temporal Logic (LTL): two widely used formalisms to express models with uncertain parts and their properties. To extract topological proofs, the new version of TOrPEDO converts the LTL formulae into an SMT instance and reuses an existing SMT solver (e.g., Microsoft Z3) to compute an unsatisfiable core. Then, the unsatisfiable core returned by the SMT solver is automatically processed to generate the topological proof. We evaluated TOrPEDO by assessing (i) how does the size of the proofs generated by TOrPEDO compares to the size of the models being analyzed; and (ii) how frequently the use of the topological proof returned by TOrPEDO avoids re-executing the model checker. Our results show that TOrPEDO provides proofs that are smaller (≈60%) than their respective initial models effectively supporting designers in creating model revisions. In a significant number of cases (≈79%), the topological proofs returned by TOrPEDO enable assessing the property satisfaction without re-running the model checker. We evaluated our new version of TOrPEDO by assessing (i) how it compares to the previous one; and (ii) how useful it is in supporting the evaluation of alternative design choices of (small) model instances in applied domains. The results show that the new version of TOrPEDO is significantly more efficient than the previous one and can compute topological proofs for models with less than 40 states within two hours. The topological proofs and counterexamples provided by TOrPEDO are useful to support the development of alternative design choices of (small) model instances in applied domains. [less ▲]

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See detailValues-Based Territorial Food Networks (VTFN): An overarching concept representing the diverse perspectives of sustainable and ethical transitions of Alternative Food Networks – be they Local Food Systems, Civic Food Networks or Short Food Supply Chains
Reckinger, Rachel UL

in Sociologia Ruralis (in press)

This article proposes a comparative literature review of the concepts Local Food Systems (LFS), Short Food Supply Chains (SFSC), Civic Food Networks (CFN) and Alternative Food Networks (AFN) – converging ... [more ▼]

This article proposes a comparative literature review of the concepts Local Food Systems (LFS), Short Food Supply Chains (SFSC), Civic Food Networks (CFN) and Alternative Food Networks (AFN) – converging into the umbrella-term Values-Based Territorial Food Networks (VTFN). Based on the analysis of the specificities and shortcomings in the four concepts, VTFN aims to enhance conceptual clarity. The current coexistence of the concepts conceals their structural and systemic commonalities – relevant for understanding pathways to ethical and sustainable food system transformations. Taking a closer look at unsolved issues and ambiguities of AFNs (subdivided into LFS, SFSC and CFNs), VTFN offers a more overarching, and pragmatic, concept. It qualifies the claimed ‘alternativeness’ of AFNs affirmatively through the dimensions of social, economic, environmental and governance ‘sustainability values’ and through varying constellations of ‘territoriality’. Thus, it fosters integrated scientific dialogue about a conceptual determination of emerging networks of food system transitions worldwide. [less ▲]

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See detailManaging talent in mission-driven organizations: A qualitative exploration
Usanova, Ksenia UL; Geraudel, Mickaël UL; D'Armagnac, Sophie et al

in International Journal of Human Resource Management (in press)

Although there is fruitful talent management (TM) literature on large private companies, little of the TM research examines mission-driven organizations (MDOs). This study addresses this gap by presenting ... [more ▼]

Although there is fruitful talent management (TM) literature on large private companies, little of the TM research examines mission-driven organizations (MDOs). This study addresses this gap by presenting TM in the context of the not-for-profit sector in Russia. Using grounded theory, we interviewed 34 top managers to understand how they define talent and how they manage such talent. The research highlights the crucial role of social values in this context. It generates a perspective on the definition of talent that differs from that of the traditional TM literature. The variety of talent definitions creates the following three different paths for TM: community-based, innovation and learning-based, and security and status-based. Then, we derive from these paths three patterns of TM practices (“managerial”, “entrepreneurial” and “amateur”) that describe the TM practices among Russian MDOs. This study contributes to the TM literature by challenging the traditional approach to TM that focuses on large private companies in Western countries. This paper links TM with social and moral values and presents three different TM patterns, which might be helpful for CEOs, executives and TM managers. [less ▲]

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See detailDBS Imaging Methods II: Electrode Localization
Husch, Andreas UL; Hertel, Frank

in Horn, Andreas (Ed.) Connectomic Deep Brain Stimulation (in press)

Connectomic Deep Brain Stimulation (DBS) covers this highly efficacious treatment option for movement disorders such as Parkinson’s Disease, Essential Tremor and Dystonia. The book examines its impact on ... [more ▼]

Connectomic Deep Brain Stimulation (DBS) covers this highly efficacious treatment option for movement disorders such as Parkinson’s Disease, Essential Tremor and Dystonia. The book examines its impact on distributed brain networks that span across the human brain in parallel with modern-day neuroimaging concepts and the connectomics of the brain. It asks several questions, including which cortical areas should DBS electrodes be connected in order to generate the highest possible clinical improvement? Which connections should be avoided? Could these connectomic insights be used to better understand the mechanism of action of DBS? How can they be transferred to individual patients, and more. This book is suitable for neuroscientists, neurologists and functional surgeons studying DBS. It provides practical advice on processing strategies and theoretical background, highlighting and reviewing the current state-of-the-art in connectomic surgery. [less ▲]

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See detailMarital Patterns and Income Inequality
Dupuy, Arnaud UL; Weber, Simon

in Economica (in press)

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See detailNIKE from Affine Determinant Programs
Barthel, Jim Jean-Pierre UL; Rosie, Razvan UL

in Qiong, Huang; Yu, Yu (Eds.) Provable and Practical Security, 15th International Conference, ProvSec 2021, Guangzhou, November 5 – November 8, 2021, Proceedings (in press)

A multi-party non-interactive key-exchange (NIKE) scheme enables N users to securely exchange a secret key K in a non-interactive manner. It is well-known that NIKE schemes can be obtained assuming the ... [more ▼]

A multi-party non-interactive key-exchange (NIKE) scheme enables N users to securely exchange a secret key K in a non-interactive manner. It is well-known that NIKE schemes can be obtained assuming the existence of indistinguishability obfuscation (iO). In this work, we revisit the original, iO-based, provably-secure NIKE construction by Boneh and Zhandry, aiming to simplify it. The core idea behind our protocol is to replace the functionality of the obfuscator with the one of an affine determinant program (ADP). Although ADPs have been designed with the purpose of attaining indistinguishability obfuscation, such implication is left open for general circuits. The ingredients enabling to prove the security of our scheme stem into a more careful analysis of the branching programs needed to build ADPs. In particular, we show: 1) An intuitive indistinguishability notion defined for ADPs of puncturable pseudorandom functions (PRFs) is sufficient to prove security for NIKE. 2) A set of simple conditions based on ADP's branching program topology that are sufficient for proving indistinguishability of ADPs. We leave open the question of finding ADPs satisfying them. [less ▲]

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See detailSISTA: Learning Optimal Transport Costs under Sparsity Constraints
Dupuy, Arnaud UL; Carlier, Guillaume; Galichon, Alfred et al

in Communications on Pure and Applied Mathematics (in press)

In this paper, we describe a novel iterative procedure called SISTA to learn the underlying cost in optimal transport problems. SISTA is a hybrid between two classical methods, coordinate descent (“S” ... [more ▼]

In this paper, we describe a novel iterative procedure called SISTA to learn the underlying cost in optimal transport problems. SISTA is a hybrid between two classical methods, coordinate descent (“S”-inkhorn) and proximal gradient descent (“ISTA”). It alternates between a phase of exact minimization over the transport potentials and a phase of proximal gradient descent over the parameters of the transport cost. We prove that this method converges linearly, and we illustrate on simulated examples that it is significantly faster than both coordinate descent and ISTA. We apply it to estimating a model of migration, which predicts the flow of migrants using country-specific characteristics and pairwise measures of dissimilarity between countries. This application demonstrates the effectiveness of machine learning in quantitative social sciences. [less ▲]

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See detailPartitioned Searchable Encryption
Barthel, Jim Jean-Pierre UL; Beunardeau, Marc; Rosie, Razvan et al

in Qiong, Huang; Yu, Yu (Eds.) Provable and Practical Security, 15th International Conference, ProvSec 2021, Guangzhou, November 5 – November 8, 2021, Proceedings (in press)

Symmetric searchable encryption (SSE) allows to outsource encrypted data to an untrusted server and retain searching capabilities. This is done without impacting the privacy of both the data and the ... [more ▼]

Symmetric searchable encryption (SSE) allows to outsource encrypted data to an untrusted server and retain searching capabilities. This is done without impacting the privacy of both the data and the search/update queries. In this work we put forth a new flavour of symmetric searchable encryption (SSE): Partitioned SSE is meant to capture the cases where the search rights must be partitioned among multiple individuals. We motivate through compelling examples the practical need for such a notion and discuss instantiations based on functional encryption and trapdoor permutations. First we leverage the power of functional encryption (FE). Our construction follows the general technique of encrypting the set of keywords and the presumably larger datafiles separately, a keyword acting as a ``pointer'' to datafiles it belongs to. To improve on the constraint factors (large ciphertext, slow encryption/decryption procedures) that are inherent in FE schemes, the keyword check is done with the help of a Bloom filter -- one per datafile: the crux idea is to split the filter into buckets, and encrypt each bucket separately under an FE scheme. Functional keys are given for binary \masks checking if relevant positions are set to 1 inside the underlying bit-vector of the Bloom filter. The second construction we present achieves forward security and stems from the scheme by Bost in CCS'16. We show that a simple tweak of the original construction gives rise to a scheme supporting updates in the partitioned setting. Moreover, the constructions take into account the possibility that some specific users are malicious while declaring their search results. [less ▲]

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See detailLehren und Lernen auf Distanz – Impulse für digitale Unterrichtsentwicklung in Luxemburg
Baumann, Isabell Eva UL; Harion, Dominic UL

in Bildungsbericht für Luxemburg 2021 (in press)

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See detailOn the (M)iNTRU assumption in the integer case
Barthel, Jim Jean-Pierre UL; Müller, Volker UL; Rosie, Razvan UL

in Provable and Practical Security, 15th International Conference, ProvSec 2021, Guangzhou, November 5 – November 8, 2021, Proceedings (in press)

In AsiaCrypt 2019, Genise, Gentry, Halevi, Li and Micciancio put forth two novel and intriguing computational hardness hypotheses: The inhomogeneous NTRU (iNTRU) assumption and its matrix version MiNTRU ... [more ▼]

In AsiaCrypt 2019, Genise, Gentry, Halevi, Li and Micciancio put forth two novel and intriguing computational hardness hypotheses: The inhomogeneous NTRU (iNTRU) assumption and its matrix version MiNTRU. In this work, we break the integer case of the iNTRU assumption through elementary lattice reduction, and we describe how the attack might be generalized to polynomial rings and to the low dimensional MiNTRU assumption with small noise. [less ▲]

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See detailA Note on the Estimation of Job Amenities and Labor Productivity
Dupuy, Arnaud UL; Galichon, Alfred

in Quantitative Economics (in press)

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See detailLife Satisfaction and the Human Development Index Across the World
Yin, Remi UL; Lepinteur, Anthony UL; Clark, Andrew et al

in Journal of Cross-Cultural Psychology (in press)

We use annual data on over 150 countries between 2005 and 2018 to look at the relationship between subjective well-being (both cognitive and affective) and the Human Development Index (HDI). The HDI ... [more ▼]

We use annual data on over 150 countries between 2005 and 2018 to look at the relationship between subjective well-being (both cognitive and affective) and the Human Development Index (HDI). The HDI appears to be more closely related to cognitive than affective well-being. We also consider the relationships between the three HDI components (the Income, Health and Education Indices) and well-being, and find that, on average, the Income Index has the strongest predictive power. Importantly, we find that the three HDI components only matter equally in Western and rich countries. Our analysis contributes to the discussion about cultural sensitivity in paradigms of societal development in two ways. We first show that differences in preferences towards development aims exist. Second, we propose a weighting procedure for a culturally-sensitive version of the HDI. [less ▲]

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See detailPrenatal exposure to endocrine disrupting chemicals is associated with altered DNA methylation in cord blood
Mattonet, Katharina; Nowack-Weyers, Nikola; Vogel, Vanessa et al

in Epigenetics (in press)

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See detailHeartbeat evoked potentials in patients with posttraumatic stress disorder: an unaltered neurobiological regulation system?
Schmitz, Marius; Müller, Laura E.; Seitz, Katja I. et al

in European Journal of Psychotraumatology (in press)

Background: Early life maltreatment is a risk factor for psychiatric disorders, including posttraumatic stress disorder (PTSD). Posttraumatic stress disorder is a severe and heterogeneous disorder with ... [more ▼]

Background: Early life maltreatment is a risk factor for psychiatric disorders, including posttraumatic stress disorder (PTSD). Posttraumatic stress disorder is a severe and heterogeneous disorder with fluctuating states of emotional over- and undermodulation including hypervigilance, dissociation, and emotion regulation deficits. The perception and regulation of emotions have been linked to interoception, the cortical representation and sensing of inner bodily processes. Although first therapeutic approaches targeting bodily sensations have been found effective in patients with PTSD, and deficits in interoceptive signal representation have been reported in other trauma-related disorders such as borderline personality disorder (BPD), the role of interoception remains largely unexplored for PTSD. Objective: The objective was to investigate the cortical representation of cardiac interoceptive signals in patients with PTSD and its associations with early life maltreatment, trait dissociation, and emotion dysregulation. Methods: Twenty-four medication-free patients with PTSD and 31 healthy controls (HC) completed a 5-min resting electrocardiogram (ECG) with parallel electroencephalogram (EEG). Heartbeat evoked potential (HEP) amplitudes as a measure for cortical representation of cardiac interoceptive signals were compared between groups and correlated with self-report questionnaires. Results: We did not find significantly different mean HEP amplitudes in patients with PTSD compared to HC, although HEPs of patients with PTSD were descriptively higher. No significant associations between mean HEP amplitudes and early life maltreatment, trait dissociation or emotion dysregulation were obtained within the groups. Conclusion: The current finding does not indicate deficits in interoceptive signal representation at rest in individuals with PTSD. Whether patients with PTSD show altered HEP modulations during emotion regulation tasks and might benefit from therapeutic approaches aiming at changing the perception of bodily signals, needs to be investigated in future studies. [less ▲]

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See detailWell-being and working from home during COVID-19
Schifano, Sonia UL; Clark, Andrew; Greiff, Samuel UL et al

in Information Technology and People (in press)

Purpose – The authors track the well-being of individuals across five European countries during the course of the coronavirus disease 2019 (COVID-19) pandemic and relate their well-being to working from ... [more ▼]

Purpose – The authors track the well-being of individuals across five European countries during the course of the coronavirus disease 2019 (COVID-19) pandemic and relate their well-being to working from home. The authors also consider the role of pandemic-policy stringency in affecting well-being in Europe. Design/methodology/approach – The authors have four waves of novel harmonised longitudinal data in France, Italy, Germany, Spain and Sweden, covering the period May–November 2020. Well-being is measured in five dimensions: life satisfaction, a worthwhile life, loneliness, depression and anxiety. A retrospective diary indicates whether the individual was working in each month since February 2020 and if so whether at home or not at home. Policy stringency is matched in per country at the daily level. The authors consider both cross- section and panel regressions and the mediating and moderating effects of control variables, including household variables and income. Findings – Well-being among workers is lower for those who work from home, and those who are not working have the lowest well-being of all. The panel results are more mitigated, with switching into working at home yielding a small drop in anxiety. The panel and cross-section difference could reflect adaptation or the selection of certain types of individuals into working at home. Policy stringency is always negatively correlated with well-being. The authors find no mediation effects. The well-being penalty from working at home is larger for the older, the better-educated, those with young children and those with more crowded housing. Originality/value – The harmonised cross-country panel data on individuals’ experiences during COVID-19 are novel. The authors relate working from home and policy stringency to multiple well-being measures. The authors emphasise the effect of working from home on not only the level of well-being but also its distribution. [less ▲]

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See detailModeling Data Protection and Privacy: Application and Experience with GDPR
Torre, Damiano UL; Alferez, Mauricio UL; Soltana, Ghanem UL et al

in Software and Systems Modeling (in press)

In Europe and indeed worldwide, the Gen- eral Data Protection Regulation (GDPR) provides pro- tection to individuals regarding their personal data in the face of new technological developments. GDPR is ... [more ▼]

In Europe and indeed worldwide, the Gen- eral Data Protection Regulation (GDPR) provides pro- tection to individuals regarding their personal data in the face of new technological developments. GDPR is widely viewed as the benchmark for data protection and privacy regulations that harmonizes data privacy laws across Europe. Although the GDPR is highly ben- e cial to individuals, it presents signi cant challenges for organizations monitoring or storing personal infor- mation. Since there is currently no automated solution with broad industrial applicability, organizations have no choice but to carry out expensive manual audits to ensure GDPR compliance. In this paper, we present a complete GDPR UML model as a rst step towards de- signing automated methods for checking GDPR compli- ance. Given that the practical application of the GDPR is infuenced by national laws of the EU Member States,we suggest a two-tiered description of the GDPR, generic and specialized. In this paper, we provide (1) the GDPR conceptual model we developed with complete trace- ability from its classes to the GDPR, (2) a glossary to help understand the model, (3) the plain-English de- scription of 35 compliance rules derived from GDPR along with their encoding in OCL, and (4) the set of 20 variations points derived from GDPR to specialize the generic model. We further present the challenges we faced in our modeling endeavor, the lessons we learned from it, and future directions for research. [less ▲]

Detailed reference viewed: 46 (5 UL)