129 research outputs found

    Learning and Mining Player Motion Profiles in Physically Interactive Robogames

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    Physically-Interactive RoboGames (PIRG) are an emerging application whose aim is to develop robotic agents able to interact and engage humans in a game situation. In this framework, learning a model of players’ activity is relevant both to understand their engagement, as well as to understand specific strategies they adopted, which in turn can foster game adaptation. Following such directions and given the lack of quantitative methods for player modeling in PIRG, we propose a methodology for representing players as a mixture of existing player’s types uncovered from data. This is done by dealing both with the intrinsic uncertainty associated with the setting and with the agent necessity to act in real time to support the game interaction. Our methodology first focuses on encoding time series data generated from player-robot interaction into images, in particular Gramian angular field images, to represent continuous data. To these, we apply latent Dirichlet allocation to summarize the player’s motion style as a probabilistic mixture of different styles discovered from data. This approach has been tested in a dataset collected from a real, physical robot game, where activity patterns are extracted by using a custom three-axis accelerometer sensor module. The obtained results suggest that the proposed system is able to provide a robust description for the player interaction

    Activity recognition in a Physical Interactive RoboGame

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    In this paper, we investigate the possibility of human physical activity recognition in a robot game scenario. Being able to recognize types of activity is essential to enable robot behavior adaptation to support player engagement. Also, the introduction of this recognition system will allow for development of better models for prediction, planning and problem solving in PIRGs that can foster human-robot interaction. The experiments reported on this paper were performed on data collected from real in-game activity, where a human player faces a mobile robot. We use a custom single tri-axial accelerometer module attached to the player’s chest in order to capture motion information. The main characteristic of our approach is the extraction of features from patterns found on the motion variance rather than on raw data. Furthermore, we allow for the recognition of unconstrained motion given that we do not ask the players to perform target activities before hand: all detectable activities are derived from the free player motion during the game itself. To the best of our knowledge, this is the first paper to consider activity recognition in a physical interactive robogame

    Lineamenti morfologici e cartografia dei popolamenti bentonici di Rada della Reale nell'isola dell’Asinara (Sardegna NW)= Morphological elements and cartography of benthic community in Rada della Reale, Asinara Island (Sardinia NW)

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    A detailed investigation of bottom types in Rada della Reale has been carried out in 1998 as part of resources study of Asinara National Park. The study area, along 23 km of coastline between Punta Barbatossa and Punta Trabucato, has a surface of 15 km2. Detailed informattin on biotic communities in the area has been recorded and transferred in a thematic map together with geomorphological features. The main benthic community is represented by the Posidonia oceanica meadow, wlth a denslty up to 700-800 shootslm2. Other seagrasses like Cymodocea nodosa and Caulerpa prolifera are also present. In the mediolittoral zone assemblages of Patella ferruginea are of main importance. Considering the great value of the area, in the future an integrated management strategy that improves conservation and enhances the value of the resources must be developed

    Core-shell nano-architectures: the incorporation mechanism of hydrophobic nanoparticles into the aqueous core of a microemulsion

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    This work presents an in-depth investigation of the molecular interactions in the incorporation mechanism of colloidal hydrophobic-capped nanoparticles into the hydrophilic core of reverse microemulsions. 1H Nuclear Magnetic Resonance (NMR) was employed to obtain molecular level details of the interaction between the nanoparticles capping amphiphiles and the microemulsion surfactants. The model system of choice involved oleic acid (OAC) and oleylamine (OAM) as capping molecules, while igepal-CO520 was the surfactant. The former were studied both in their ‘‘free’’ state and ‘‘ligated’’ one, i.e., bound to nanoparticles. The latter was investigated either in cyclohexane (micellar solution) or in water/cyclohexane microemulsions. The approach was extremely useful to gain a deeper understanding of the equilibria involved in this complex system (oleic acid capped-Bi2S3 in igepal/water/cyclohexane microemulsions). In difference to previously proposed mechanisms, the experimental data showed that the high affinity of the capping ligands for the reverse micelle interior was the driving force for the incorporation of the nanoparticles. A simple ligand-exchange mechanism could be ruled out. The collected information about the nanoparticle incorporation mechanism is extremely useful to develop new synthetic routes with an improved/tuned coating efficiency, in order to tailor the core–shell structure preparation

    Mitochondria Morphology and DNA Content upon Sublethal Exposure to Beta-Amyloid1–42 Peptide

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    Brains affected by Alzheimer’s disease (AD) show a large spectrum of mitochondrial alterations at both morphological and genetic level. The causal link between amyloid beta peptides (Ab) and mitochondrial dysfunction has been established in cellular models of AD using Ab concentrations capable of triggering massive neuronal death. However, mitochondrial changes related to sublethal exposure to Ab are less known. Here we show that subtoxic, 1 mMAb1–42 exposure does not change the mitochondrial shape of living cells, as visualized upon the uptake of the non-potentiometric fluorescent probe Mitotracker Green and enhanced yellow fluorescent protein (EYFP)-tagged cytochrome c oxidase expression. Immunolocalization of oxidative adducts 8-hydroxy-2’-deoxyguanosine, 8-hydroxyguanine and 8-hydroxyguanosine demonstrates that one-micromolar concentration of Ab1–42 is also not sufficient to elicit dramatic qualitative changes in the RNA/DNA oxidative products. However, in comparison with controls, semi-quantitative analysis of the overall mitochondrial mass by integrated fluorescence intensity reveals an ongoing down-regulation in mitochondrial biosynthesis or, conversely, an enhanced autophagic demise of Ab treated cells. Furthermore, a significant increase of the full-length mitochondrial DNA (mtDNA) from Ab-treated versus control cells is found, as measured by long range polymerase chain reaction (PCR). Such up-regulation is accompanied by extensive fragmentation of the unamplified mtDNA, probably due to the detrimental effect of Ab. We interpret these results as a sequence of compensatory responses induced by mtDNA damage, which are devoted to repression of oxidative burst. In conclusion, our findings suggest that early therapeutic interventions aimed at prevention of mitochondrial oxidative damage may delay AD progression and help in treating AD patients

    Fatty Acid Profile and Antimicrobial Activity of Rubus ulmifolius Schott Extracts Against Cariogenic Bacterium Streptococcus mutans

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    Abstract: The wild edible species Rubus ulmifolius is normally known as a source of several functional- natural compounds used in the traditional diet in several parts of the world. At present, few data are available in the literature about the biological property of its leaves, normally rich in phenolic acids, fatty acids, and other organic compounds with potential antimicrobial activity. Following this hypothesis, we have investigated the antibacterial activity of different dried leaved extracts against the main cariogenic bacterium, Streptococcus mutans. Standard antimicrobial-antibiofilm methods (MIC, MBC, MBIC) were performed to evaluate each extract's antimicrobial profile. In addition, the fatty acids (FA) quali-quantitative profile of R. ulmifolius leave extracts was assessed by reversed-phase HPLC-DAD/ELSD analysis. The results showed that the behavior of this bacterium with different extracts was strictly related to extraction method type, even though it was not related to fatty acid amount and composition, in fact, all the extracts showed similar, qualitative FA patterns, characterized by a concentration in the range from (25 to 36) % of saturated compounds. The methanolic extract showed the better result as antibacterial MIC 6.25 %. These preliminary results encourage further studies for the use of R. ulmifolius in mouthwashes or toothpaste with great anticaries activity

    Human-like problem-solving abilities in large language models using ChatGPT

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    BackgroundsThe field of Artificial Intelligence (AI) has seen a major shift in recent years due to the development of new Machine Learning (ML) models such as Generative Pre-trained Transformer (GPT). GPT has achieved previously unheard-of levels of accuracy in most computerized language processing tasks and their chat-based variations.AimThe aim of this study was to investigate the problem-solving abilities of ChatGPT using two sets of verbal insight problems, with a known performance level established by a sample of human participants.Materials and methodsA total of 30 problems labeled as “practice problems” and “transfer problems” were administered to ChatGPT. ChatGPT's answers received a score of “0” for each incorrectly answered problem and a score of “1” for each correct response. The highest possible score for both the practice and transfer problems was 15 out of 15. The solution rate for each problem (based on a sample of 20 subjects) was used to assess and compare the performance of ChatGPT with that of human subjects.ResultsThe study highlighted that ChatGPT can be trained in out-of-the-box thinking and demonstrated potential in solving verbal insight problems. The global performance of ChatGPT equalled the most probable outcome for the human sample in both practice problems and transfer problems as well as upon their combination. Additionally, ChatGPT answer combinations were among the 5% of most probable outcomes for the human sample both when considering practice problems and pooled problem sets. These findings demonstrate that ChatGPT performance on both set of problems was in line with the mean rate of success of human subjects, indicating that it performed reasonably well.ConclusionsThe use of transformer architecture and self-attention in ChatGPT may have helped to prioritize inputs while predicting, contributing to its potential in verbal insight problem-solving. ChatGPT has shown potential in solving insight problems, thus highlighting the importance of incorporating AI into psychological research. However, it is acknowledged that there are still open challenges. Indeed, further research is required to fully understand AI's capabilities and limitations in verbal problem-solving

    Cyanobacterial dynamics and toxins concentrations in Lake Alto Flumendosa, Sardinia, Italy

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    Seasonal blooms of cyanobacteria (CB) are a typical feature of Lake Alto Flumendosa (Sardinia, Italy). The waters of this lake are used for drinking water supply, for agricultural and industrial uses, and fish farming activities. Since cyanotoxins are not monitored in edible organisms, diet could be a relevant route of human exposure. CB also represent a threat for the health of wild and domestic animals that use lake water for beverage. Therefore, to characterize the CB community and assess the risk for human and animal population, CB dynamic, mcyB+ fraction, and microcystins (MCs) concentration have been followed monthly for 18 months, in three stations. Results confirmed the presence of several toxigenic species. Planktothrix rubescens dominated between August 2011 and April 2012 (3.5×106 cells L-1), alternating with Woronichinia naegeliana (8×106 cells L-1) and Microcystis botrys (9×105 cells L-1). Dolichospermum planctonicum was always present at low densities (104 cells L-1). MCs were detected, at values well below the 1 µg L-1 threshold of WHO for drinking water. The molecular analysis of mcyB gene for P. rubescens indicated the presence of a persistent toxic population (average 0.45 mcyB/16S rDNA). Highly significant linear regressions were found between P. rubescens and the sum of the demethylated MC variants, and between M. botrys and the sum of MC-LR and MC-LA, also when co-occurring, suggesting that these two species were responsible for different MC patterns production. The regression lines indicated a quite stable MC cell quota. However, in some spotted samples very different values were obtained for both MC concentrations and cell quota (from 10-fold lower to 30-40-fold higher than the 'average') showing an unexpected significant variability in the rate of toxin production. The relatively low cell densities during the monitoring period is consistent with the low-to absent MC contamination level found in trout muscle; however, the analytical method was affected by low recovery, probably due to MC-protein binding. Our results show that, during the study period, no risk of exposure for the human and animal population occurred. However, the persistence of a complex CB community characterised by a significant toxic fraction suggests the need for periodic monitoring activity. Particularly, the hidden deep summer P. rubescens blooms, located where water is taken for drinking water supply, and M. botrys, able to produce the most toxic MC variants with high cell quota, should be kept under control. The documentation and interpretation of sudden changes in toxins concentrations deserve special attention. This is particularly relevant in proximity of fish farming plants and water catchment sites

    Distinct Mechanisms Are Responsible for Nrf2-Keap1 Pathway Activation at Different Stages of Rat Hepatocarcinogenesis

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    Activation of the Nrf2-Keap1 pathway, the main intracellular defense against environmental stress, has been observed in several human cancers, including hepatocellular carcinoma (HCC). Here, we assessed whether distinct mechanisms of activation may be involved at different stages of hepatocarcinogenesis. We adopted an experimental model consisting of treatment with diethylnitrosamine (DENA) followed by a choline-devoid methionine-deficient (CMD) diet for 4 months. The CMD diet was then replaced with a basal diet, and the animals were killed at 6, 10 or 13 months after DENA injection. Nrf2 activation occurred at early steps of hepatocarcinogenesis and persisted throughout the tumorigenic process. WhileNrf2mutations were extremely frequent at early steps (90%), their incidence diminished with the progression to malignancy (25%). Conversely, while p62 was almost undetectable in early nodules, its accumulation occurred in HCCs, suggesting that Nrf2 pathway activation at late stages is mainly due to Keap1 sequestration by p62. We demonstrate that, in a model of hepatocarcinogenesis resembling human non-alcoholic fatty liver disease,Nrf2mutations are the earliest molecular changes responsible for the activation of the Nrf2-Keap1 pathway. The progressive loss of mutations associated with a concomitant p62 accumulation implies that distinct mechanisms are responsible for Nrf2-Keap1 pathway activation at different stages of hepatocarcinogenesis
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