Classical plan recognition approaches require restrictive assumptions and are generally off-line. However, many real-world plan recognition applications must deal with real-time constraints, noisy ...information, temporal relations in actions, agent preferences, and so on. Many existing approaches have tried to relax assumptions, but none can deal with the above-cited needs. This paper proposes an extension of previous works on plan recognition based on plan tree grammar. Our anytime topdown approach uses a particle filter. This approach manages to give a quick reliable solution to the plan recognition problem while dealing with noisy observations and without reducing the expressiveness of plan libraries. Empirical results on simulated problems show the efficiency of our approach.
Mobile robot assistants have many applications, such as helping people in their daily living activities. These robots have to detect and recognize the actions and goals of the humans they are ...assisting. While there are several wide-spread plan and activity recognition solutions for controlled environments with many built-in sensors, like smart-homes, there is a lack of such systems for mobile robots operating in open settings, such as an apartment. We propose a module for the recognition of activities and goals for daily living by mobile robots, in real time and for complex activities. Our approach recognizes human-object interaction using an RGB-D camera to infer low-level actions which are sent to a goal recognition algorithm. Results show that our approach is both in real time and requires little computational resources, which facilitates its deployment on a mobile and low-cost robotics platform.
In a previous paper, we proposed a serious game architecture allowing automatic generation of pedagogical scenarios. The player module of our architecture tracks players' knowledge progression, and ...the adaptation module can optimize pedagogical scenarios to enhance skill acquisition taught by the game. In Game of Homes, the player has to become the best real estate agent in a city. In the present study, we hypothesized that automatically generated scenarios lead to better learning as opposed to scripted-based scenarios. We used two Game of Homes configurations: one based on our architecture, which automatically generated pedagogical scenarios, and one in which pedagogical scenarios were scripted. In both versions, the player module was activated to trace skill acquisition. Both configurations targeted the same two essential skills linked to house sales. After rounds of player testing, we analyzed logs files of games of both configurations to be able to compare them. Eighteen adults (10 women and 8 men) played Game of Homes for 80 minutes. Each of them was randomly assigned either the scripted-based or automatically generated version. In our analysis, we focused on (1) knowledge progression data and skills acquisition provided by the player module, (2) the amount of hints and help messages displayed and (3) the pedagogical scenarios proceedings. We also developed a processing tool that allowed us to analyze the game logs and visualize the learning rate of specific strategies taught in the game. The main results of the qualitative analysis highlighted the originality of generated pedagogical scenarios and, more specifically, the optimization of the guidance and presentation of contents to be learned in the game. Generated scenarios were composed of less pedagogical actions of the game system than scripted-based scenarios, leading to faster skill acquisition by the players.
La voie ERK/MAPK est impliquée dans plusieurs processus biologiques dont la prolifération cellulaire, la différenciation, l'apoptose et la migration. Les protéines kinases MEK1 et MEK2 sont les seuls ...activateurs connus d'ERKl et ERK2. Les mutations inactivant les gènes Mekl et Mek2 ont été développées chez la souris pour étudier les fonctions des ces deux activateurs lors du développement embryonnaire. L'analyse phénotypique des mutants Mekl" montre une diminution de la prolifération et une augmentation de l'apoptose des populations trophoblastiques. Les embryons Mekïf~ meurent à mi-gestation d'une sous-vascularisation du labyrinthe placentaire qui normalement permet les échanges gazeux et nutritiormels foeto-maternels. Des analyses histologiques suggèrent également un problème de migration lors des processus d'invagination du réseau vasculaire. Ces résultats montrent que MEK1 est impliqué spécifiquement dans certaines fonctions des trophoblastes et que son absence induit une dysmorphogénèse létale du placenta murin. Pour étudier l'implication spécifique de MEK1 dans ces populations trophoblastiques, des modèles cellulaires ont été établis.
REDUCING INEQUALITIES AMONG UNEQUALS Faure, Mathieu; Gravel, Nicolas
International economic review (Philadelphia),
February 2021, 2021-02-00, 20210201, 2021-02, Letnik:
62, Številka:
1
Journal Article
Recenzirano
Odprti dostop
This article establishes an equivalence between four incomplete rankings of distributions of income among agents who are vertically differentiated with respect to some nonincome characteristic ...(health, household size, etc.). The first ranking is the possibility of going from one distribution to the other by a finite sequence of income transfers from richer and more highly ranked agents to poorer and less highly ranked ones. The second ranking is the unanimity among utilitarian planners who assume that agents' marginal utility of income is decreasing with respect to both income and the source of vertical differentiation. The third ranking is the Bourguignon (Journal of Econometrics, 42 (1989), 67–80) Ordered Poverty Gap dominance criterion. The fourth ranking is a new dominance criterion based on cumulative lowest incomes.
Adult neuronal precursors retain the remarkable capacity to migrate long distances from the posterior (subventricular zone) to the most anterior olfactory bulb (OB) parts of the brain. The knowledge ...about the mechanisms that keep neuronal precursors in the migratory stream and organize this long-distance migration is incomplete. Here we show that blood vessels precisely outline the migratory stream for new neurons in the adult mammalian forebrain. Real-time video imaging of cell migration in the acute slices demonstrate that neuronal precursors are retained in the migratory stream and guided into the OB by blood vessels that serve as a physical substrate for migrating neuroblasts. Our data suggest that endothelial cells of blood vessels synthesize brain-derived neurotrophic factor (BDNF) that fosters neuronal migration via p75NTR expressed on neuroblasts. Interestingly, GABA released from neuroblasts induces Ca(2+)-dependent insertion of high-affinity TrkB receptors on the plasma membrane of astrocytes that trap extracellular BDNF. We hypothesize that this renders BDNF unavailable for p75NTR-expressing migrating cells and leads to their entrance into the stationary period. Our findings provide new insights into the functional organization of substrates that facilitate the long-distance journey of adult neuronal precursors.
Abstract
Recent reports have identified differences in the mutational spectra across human populations. Although some of these reports have been replicated in other cohorts, most have been reported ...only in the 1000 Genomes Project (1kGP) data. While investigating an intriguing putative population stratification within the Japanese population, we identified a previously unreported batch effect leading to spurious mutation calls in the 1kGP data and to the apparent population stratification. Because the 1kGP data are used extensively, we find that the batch effects also lead to incorrect imputation by leading imputation servers and a small number of suspicious GWAS associations. Lower quality data from the early phases of the 1kGP thus continue to contaminate modern studies in hidden ways. It may be time to retire or upgrade such legacy sequencing data.
Human herpesvirus 6B (HHV-6B) is a ubiquitous pathogen causing lifelong infections in approximately 95% of humans worldwide. To persist within its host, HHV-6B has developed several immune evasion ...mechanisms, such as latency, during which minimal proteins are expressed, and the ability to disturb innate and adaptive immune responses. The primary cellular targets of HHV-6B are CD4(+) T cells. Previous studies by Flamand et al. (L. Flamand, J. Gosselin, I. Stefanescu, D. Ablashi, and J. Menezes, Blood 85:1263-1271, 1995) reported on the capacity of HHV-6A as well as UV-irradiated HHV-6A to inhibit interleukin-2 (IL-2) synthesis in CD4(+) lymphocytes, suggesting that viral structural components could be responsible for this effect. In the present study, we identified the HHV-6B U54 tegument protein (U54) as being capable of inhibiting IL-2 expression. U54 binds the calcineurin (CaN) phosphatase enzyme, causing improper dephosphorylation and nuclear translocation of NFAT (nuclear factor of activated T cells) proteins, resulting in suboptimal IL-2 gene transcription. The U54 GISIT motif (amino acids 293 to 297), analogous to the NFAT PXIXIT motif, contributed to the inhibition of NFAT activation. IMPORTANCE Human herpesvirus 6A (HHV-6A) and HHV-6B are associated with an increasing number of pathologies. These viruses have developed strategies to avoid the immune response allowing them to persist in the host. Several studies have illustrated mechanisms by which HHV-6A and HHV-6B are able to disrupt host defenses (reviewed in L. Dagna, J. C. Pritchett, and P. Lusso, Future Virol. 8:273-287, 2013, doi:10.2217/fvl.13.7). Previous work informed us that HHV-6A is able to suppress synthesis of interleukin-2 (IL-2), a key immune growth factor essential for adequate T lymphocyte proliferation and expansion. We obtained evidence that HHV-6B also inhibits IL-2 gene expression and identified the mechanisms by which it does so. Our work led us to the identification of U54, a virion-associated tegument protein, as being responsible for suppression of IL-2. Consequently, we have identified HHV-6B U54 protein as playing a role in immune evasion. These results further contribute to our understanding of HHV-6 interactions with its human host and the efforts deployed to ensure its long-term persistence.
Nuclear factor of activated T cell (NFAT) proteins are key regulators involved in multiple physiological mechanisms, such as immune response and cell growth. The capacity of selective ...calcineurin/NFAT inhibitors to decrease NFAT-dependent cancer cell progression, particularly in breast cancer, has already been demonstrated. In this study, we report a role for the human herpesvirus 6B (HHV-6B) U54 tegument protein in inhibiting MCF-7 breast cancer cell proliferation by inhibiting NFAT activation.
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