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Network of interactions between ciliates and phytoplankton during spring
Get PDFThe annually recurrent spring phytoplankton blooms in freshwater lakes initiate pronounced successions of planktonic ciliate species. Although there is considerable knowledge on the taxonomic diversity of these ciliates, their species-specific interactions with other microorganisms are still not well understood. Here we present the succession patterns of 20 morphotypes of ciliates during spring in Lake Zurich, Switzerland, and we relate their abundances to phytoplankton genera, flagellates, heterotrophic bacteria, and abiotic parameters. Interspecific relationships were analyzed by contemporaneous correlations and time-lagged co-occurrence and visualized as association networks. The contemporaneous network pointed to the pivotal role of distinct ciliate species (e.g., Balanion planctonicum, Rimostrombidium humile) as primary consumers of cryptomonads, revealed a clear overclustering of mixotrophic/omnivorous species, and highlighted the role of Halteria/Pelagohalteria as important bacterivores. By contrast, time-lagged statistical approaches (like local similarity analyses, LSA) proved to be inadequate for the evaluation of high-frequency sampling data. LSA led to a conspicuous inflation of significant associations, making it difficult to establish ecologically plausible interactions between ciliates and other microorganisms. Nevertheless, if adequate statistical procedures are selected, association networks can be powerful tools to formulate testable hypotheses about the autecology of only recently described ciliate species
Patterns of taxonomic diversity among terrestrial isopods
Get PDFThe publication of the world catalog of terrestrial isopods some ten years ago by Schmalfuss has facilitated research on isopod diversity patterns at a global scale. Furthermore, even though we still lack a comprehensive and robust phylogeny of Oniscidea, we do have some useful approaches to phylogenetic relationships among major clades which can offer additional insights into isopod evolutionary dynamics. Taxonomic diversity is one of many approaches to biodiversity and, despite its sensitiveness to biases in taxonomic practice, has proved useful in exploring diversification dynamics of various taxa. In the present work, we attempt an analysis of taxonomic diversity patterns among Oniscidea based on an updated world list of species containing 3,710 species belonging to 527 genera and 37 families (data till April 2014). The analysis explores species diversity at the genus and family level, as well as the relationships between species per genera, species per families, and genera per families. In addition, we consider the structure of isopod taxonomic system under the fractal perspective that has been proposed as a measure of a taxon\u27s diversification. Finally, we check whether there is any phylogenetic signal behind taxonomic diversity patterns. The results can be useful in a more detailed elaboration of Oniscidea systematics
Ecological active vision: four bio-inspired principles to integrate bottom-up and adaptive top-down attention tested with a simple camera-arm robot
Get PDFVision gives primates a wealth of information useful to manipulate the environment, but at the same time it can easily overwhelm their computational resources. Active vision is a key solution found by nature to solve this problem: a limited fovea actively displaced in space to collect only relevant information. Here we highlight that in ecological conditions this solution encounters four problems: 1) the agent needs to learn where to look based on its goals; 2) manipulation causes learning feedback in areas of space possibly outside the attention focus; 3) good visual actions are needed to guide manipulation actions, but only these can generate learning feedback; and 4) a limited fovea causes aliasing problems. We then propose a computational architecture ("BITPIC") to overcome the four problems, integrating four bioinspired key ingredients: 1) reinforcement-learning fovea-based top-down attention; 2) a strong vision-manipulation coupling; 3) bottom-up periphery-based attention; and 4) a novel action-oriented memory. The system is tested with a simple simulated camera-arm robot solving a class of search-and-reach tasks involving color-blob "objects." The results show that the architecture solves the problems, and hence the tasks, very ef?ciently, and highlight how the architecture principles can contribute to a full exploitation of the advantages of active vision in ecological conditions
Generalisation, decision making, and embodiment effects in mental rotation: A neurorobotic architecture tested with a humanoid robot
Get PDFMental rotation, a classic experimental paradigm of cognitive psychology, tests the capacity of humans to mentally rotate a seen object to decide if it matches a target object. In recent years, mental rotation has been investigated with brain imaging techniques to identify the brain areas involved. Mental rotation has also been investigated through the development of neural-network models, used to identify the specific mechanisms that underlie its process, and with neurorobotics models to investigate its embodied nature. Current models, however, have limited capacities to relate to neuro-scientific evidence, to generalise mental rotation to new objects, to suitably represent decision making mechanisms, and to allow the study of the effects of overt gestures on mental rotation. The work presented in this study overcomes these limitations by proposing a novel neurorobotic model that has a macro-architecture constrained by knowledge held on brain, encompasses a rather general mental rotation mechanism, and incorporates a biologically plausible decision making mechanism. The model was tested using the humanoid robot iCub in tasks requiring the robot to mentally rotate 2D geometrical images appearing on a computer screen. The results show that the robot gained an enhanced capacity to generalise mental rotation to new objects and to express the possible effects of overt movements of the wrist on mental rotation. The model also represents a further step in the identification of the embodied neural mechanisms that may underlie mental rotation in humans and might also give hints to enhance robots\u27 planning capabilities
L?identit? digitale: dalle nuove frontiere del Sistema Pubblico di Identificazione (SPID) alle problematiche legate al web
Get PDFL\u27emergere del concetto di identit? online ha generato un ampio dibattito nel mondo accademico. L?identit? digitale pu? essere vista sotto un duplice aspetto. Da un lato le credenziali che ognuno possiede, e ci? trova il suo fondamento nel nuovissimo Sistema Pubblico per la gestione dell?Identit? Digitale di cittadini e imprese (SPID). Dall\u27altro lato, l?identit? digitale ? la rappresentazione virtuale dell?identit? reale, che pu? essere usata durante interazioni elettroniche con persone o macchine. L\u27identit? ? piuttosto mutevole, in continua evoluzione e trasformazione, sulla base delle esperienze che ogni individuo vive. In questo modo, il diritto all?identit? personale implica una serie di corollari quali: il diritto a un nome, il diritto di replica, il diritto alla protezione dei dati personali e il diritto di un?immagine. Se traduciamo il diritto all?identit? personale alla nostra epoca digitalizzata, con il suo uso massiccio dei social network, ? necessario aggiungere al relativo decalogo dei diritti, il diritto all\u27oblio, ugualmente chiamato diritto di essere dimenticati. Sar? quindi possibile identificare le protezioni che le persone possono mettere in atto per difendere la propria identit? e il diritto all\u27oblio
Modeling urban-level impact of a shared taxi market
Get PDFTaxi systems are being challenged by alternative, emerging services like Uber, Lyft, and Sidecar, which increasingly offer the option of ride sharing. While the enormous potential of ride sharing has been unveiled in a number of recent papers, it also raised legitimate concerns about the potentially disruptive impact on other transportation modes. In this paper, we introduce a framework for estimating the urban-level impact of ride sharing applied to the current taxicab service. First, we extend a representative economic model of regulated taxi markets to include ride sharing. The model allows predicting the interactions between demand and supply of a shared taxi service based on a few representative parameters, and is rooted on data analytical results. Then, we apply our model to the case study of the New York taxi market. The analysis highlights the dramatic impact of the pricing policy and taxi fleet management on the urban-level, systemic outcomes of a shared taxi system
Visual Detection Of Singularities In Review Platforms
Get PDFProduct and service reviews can markedly influence consumer purchase decisions, leading to financial gains or losses for businesses. Therefore, there is a growing interest towards techniques for bringing out reviews that could negatively or positively bias new customers. To this goal, we propose a visual analysis of reviews that enables quick elicitation of interesting patterns and singularities. The proposed approach is based on a theoretically sound framework, while its effectiveness and viability is demonstrated by its application to real data extracted from Tripadvisor and Booking.com
1st IEEE/ACM International Workshop on TEchnical and LEgal aspects of data pRIvacy and SEcurity, TELERISE 2015, Florence, Italy, May 18, 2015.
No full textThis paper is the report on the 1st International Workshop on TEchnical and LEgal aspects of data pRIvacy and SEcurity (TELERISE 2015) at the 37th International Conference on Software Engineering (ICSE 2015). TELERISE investigates privacy and security issues in data sharing from a technical and legal perspective. Keynote speech as well as selected papers presented at the event fit the topics of the workshop. This report gives the rationale of TELERISE and it provides a provisional program
ALPHA: an eAsy inteLligent service Platform for Healthy Ageing
Get PDFDementia is one of the biggest global public health challenges facing our generation. Alzheimers disease (AD) is the most frequent cause of dementia in elderly people over 65 years of age. The typical characteristic of AD is impairment of memory. As the disease progresses, other cognitive domains such as language, praxis, visuo-spatial and executive functions become involved, eventually resulting in global cognitive decline. Behavioral Psychological Symptoms of Dementia (BPSD) problems are constant in AD and have highly negative impact on the quality of life of patients and their families. ALPHA project aims at developing an intelligent situation-aware system to collect and process information about Alzheimer Disease patients? life style. Starting from various data provided by caregivers and a set of non-invasive sensors and devices. ALPHA will provide clinicians with new quantitative and qualitative information about patients? abnormal behavior which, along with medical data, will enhance the accuracy and reliability of monitoring and assessing the patient?s health status. Clinicians will be supported by a suite of specifically designed tools and interfaces to analyze the metadata captured, improve management of personalized care plans and better interact with patients and caregivers. Studies of antique records of former psychiatric hospital will enable us towiden the knowledge of behavioral disorders thus allowing to compare the ancient ones and the curcurrent and to probabilistically determine relation between type of dementia and behavioral disorders
Semantic Web and the Future of Health Care Data in Family Practice
No full textNew tools in data management have emerged in the last decade, which are going to revolutionize electronic health records and health information systems. Family practitioners are the first, main and continuous contact with the patient. They are the source and endpoint of the circle of information, generated by judicious medical documentation and smart secondary use of medical data. This article is an introduction to health terminologies, ontologies, semantic data, and linked open data, all expressions used by computer scientists, preparing themselves for the next step: semantic web for health care data