UNTAG: Learning Generic Features for Unsupervised Type-Agnostic Deepfake Detection

in IEEE International Conference on Acoustics, Speech and Signal Processing. Proceedings (2023)

This paper introduces a novel framework for unsupervised type-agnostic deepfake detection called UNTAG. Existing methods are generally trained in a supervised manner at the classification level, focusing ... [more ▼]

This paper introduces a novel framework for unsupervised type-agnostic deepfake detection called UNTAG. Existing methods are generally trained in a supervised manner at the classification level, focusing on detecting at most two types of forgeries; thus, limiting their generalization capability across different deepfake types. To handle that, we reformulate the deepfake detection problem as a one-class classification supported by a self-supervision mechanism. Our intuition is that by estimating the distribution of real data in a discriminative feature space, deepfakes can be detected as outliers regardless of their type. UNTAG involves two sequential steps. First, deep representations are learned based on a self-supervised pretext task focusing on manipulated regions. Second, a one-class classifier fitted on authentic image embeddings is used to detect deepfakes. The results reported on several datasets show the effectiveness of UNTAG and the relevance of the proposed new paradigm. The code is publicly available. [less ▲]

Le long chemin de la réglementation européenne du travail sur plateforme

in Nicod, Cécile; Miranda Boto, José Maria; Brameshuber, Elisabeth (Eds.) et al Négociation collective et plateformes numériques (2023)

Public family firms and economic inequality across societies

in Journal of Business Venturing Insights (2023), e00376

Research and public interest on economic inequality have grown over the last years. Family firms and the concentration of wealth and power in the hands of a few wealthy entrepreneurial families have been ... [more ▼]

Research and public interest on economic inequality have grown over the last years. Family firms and the concentration of wealth and power in the hands of a few wealthy entrepreneurial families have been discussed as both a cause and a consequence of economic inequality. Yet, so far, we lack knowledge about the relationship between economic inequality and the prevalence of family firms in an economy. Our study investigates how the share of family-controlled public firms correlates with various measures of income and wealth inequality. The results show that a higher share of public family-controlled firms leads to more income inequality in a country. This effect is particularly pronounced for the middle of the income distribution as opposed to the top quantiles. Redistribution only mitigates this effect to some extent, as the effect is significant for market income and disposable income. We also find that a higher share of family-controlled firms contributes to an increase in wealth inequality. Our results are of economic relevance as, for instance, a one standard deviation change in the share of family-controlled firms leads to an increase of around 1.3–1.5 percentage points in the Gini coefficients for market income, disposable income, and wealth. [less ▲]

Ambra1 modulates the tumor immune microenvironment and response to PD-1 blockade in melanoma.

in Journal for immunotherapy of cancer (2023), 11(3),

BACKGROUND: Loss of Ambra1 (autophagy and beclin 1 regulator 1), a multifunctional scaffold protein, promotes the formation of nevi and contributes to several phases of melanoma development. The ... [more ▼]

BACKGROUND: Loss of Ambra1 (autophagy and beclin 1 regulator 1), a multifunctional scaffold protein, promotes the formation of nevi and contributes to several phases of melanoma development. The suppressive functions of Ambra1 in melanoma are mediated by negative regulation of cell proliferation and invasion; however, evidence suggests that loss of Ambra1 may also affect the melanoma microenvironment. Here, we investigate the possible impact of Ambra1 on antitumor immunity and response to immunotherapy. METHODS: This study was performed using an Ambra1-depleted Braf(V600E) /Pten(-/) (-) genetically engineered mouse (GEM) model of melanoma, as well as GEM-derived allografts of Braf(V600E) /Pten(-/) (-) and Braf(V600E) /Pten(-/) (-)/Cdkn2a(-/) (-) tumors with Ambra1 knockdown. The effects of Ambra1 loss on the tumor immune microenvironment (TIME) were analyzed using NanoString technology, multiplex immunohistochemistry, and flow cytometry. Transcriptome and CIBERSORT digital cytometry analyses of murine melanoma samples and human melanoma patients (The Cancer Genome Atlas) were applied to determine the immune cell populations in null or low-expressing AMBRA1 melanoma. The contribution of Ambra1 on T-cell migration was evaluated using a cytokine array and flow cytometry. Tumor growth kinetics and overall survival analysis in Braf(V600E) /Pten(-/) (-)/Cdkn2a(-/) (-) mice with Ambra1 knockdown were evaluated prior to and after administration of a programmed cell death protein-1 (PD-1) inhibitor. RESULTS: Loss of Ambra1 was associated with altered expression of a wide range of cytokines and chemokines as well as decreased infiltration of tumors by regulatory T cells, a subpopulation of T cells with potent immune-suppressive properties. These changes in TIME composition were associated with the autophagic function of Ambra1. In the Braf(V600E) /Pten(-/) (-)/Cdkn2a(-/) (-) model inherently resistant to immune checkpoint blockade, knockdown of Ambra1 led to accelerated tumor growth and reduced overall survival, but at the same time conferred sensitivity to anti-PD-1 treatment. CONCLUSIONS: This study shows that loss of Ambra1 affects the TIME and the antitumor immune response in melanoma, highlighting new functions of Ambra1 in the regulation of melanoma biology. [less ▲]

Of swords and shields: due process and crime control in times of globalization - Liber amicorum prof. dr. J.A.E. Vervaele

Book published by Eleven (2023)

The Europeanization of Parliamentary Administrations

in Christiansen, Thomas; Griglio, Elena; Lupo, Nicola (Eds.) The Routledge Hanbook of Parliamentary Administrations (2023)

How to deal with rule of law-concerns in surrender procedures?

in Luchtman, Michiel; Ligeti, Katalin; Tosza, Stanislaw (Eds.) Of swords and shields: due process and crime control in times of globalization - Liber amicorum prof. dr. J.A.E. Vervaele (2023)

Schedulability Analysis of CAN and CAN FD Authentication

Scientific Conference (2023)

Ensuring the data integrity of messages transmitted over the Controller Area Network (CAN) bus and other vehicular networks is achieved through the implementation of cryptographic authentication protocols ... [more ▼]

Ensuring the data integrity of messages transmitted over the Controller Area Network (CAN) bus and other vehicular networks is achieved through the implementation of cryptographic authentication protocols. However, these protocols raise concerns about a significant increase in response time due to the restrictions on CAN frame size and bandwidth. This paper presents a comprehensive analysis of the impact on response time of CAN and CAN Flexible Data-rate (CAN FD) messages with the implementation of cryptographic message authentication codes (MACs) and the periodic transmission of these codes. Our evaluation is based on a randomized schedulability experiment to provide insights into the overhead incurred by adding authentication to the frame payloads. [less ▲]

ADDRESSING THE IMPACT OF MAINTENANCE IN SHUNTING OPERATIONS THROUGH SHUNT-IN POLICIES FOR FREIGHT TRAINS OPERATIONS.

Scientific Conference (2023)

Scalable Coercion-Resistant E-Voting under Weaker Trust Assumptions

in Proceedings of ACM SAC Conference (SAC'23) (2023)

Electronic voting (e-voting) is regularly used in many countries and organizations for legally binding elections. In order to conduct such elections securely, numerous e-voting systems have been proposed ... [more ▼]

Electronic voting (e-voting) is regularly used in many countries and organizations for legally binding elections. In order to conduct such elections securely, numerous e-voting systems have been proposed over the last few decades. Notably, some of these systems were designed to provide coercion-resistance. This property protects against potential adversaries trying to swing an election by coercing voters. Despite the multitude of existing coercion-resistant e-voting systems, to date, only few of them can handle large-scale Internet elections efficiently. One of these systems, VoteAgain (USENIX Security 2020), was originally claimed secure under similar trust assumptions to state-of-the-art e-voting systems without coercion-resistance. In this work, we review VoteAgain's security properties. We discover that, unlike originally claimed, VoteAgain is no more secure than a trivial voting system with a completely trusted election authority. In order to mitigate this issue, we propose a variant of VoteAgain which effectively mitigates trust on the election authorities and, at the same time, preserves VoteAgain's usability and efficiency. Altogether, our findings bring the state of science one step closer to the goal of scalable coercion-resistant e-voting being secure under reasonable trust assumptions. [less ▲]