Machine Learning for Aggregate Computing: a Research Roadmap

Aggregate computing is a macro-approach for programming collective intelligence and self-organisation in distributed systems. In this paradigm, a single 'aggregate program' drives the collective behaviour of the system, provided that the agents follow an execution protocol consisting of asynchronous sense-compute-act rounds. For actual execution, a proper aggregate computing middleware or platform has to be deployed across the nodes of the target distributed system, to support the services needed for the execution of applications. Overall, the engineering of aggregate computing applications is a rich activity that spans multiple concerns including designing the aggregate program, developing reusable algorithms, detailing the execution model, and choosing a deployment based on available infrastructure. Traditionally, these activities have been carried out through ad-hoc designs and implementations tailored to specific contexts and goals. To overcome the complexity and cost of manually tailoring or fixing algorithms, execution details, and deployments, we propose to use machine learning techniques, to automatically create policies for applications and their management. To support such a goal, we detail a rich research roadmap, showing opportunities and challenges of integrating aggregate computing and learning

Towards Reinforcement Learning-based Aggregate Computing

Recent trends in pervasive computing promote the vision of Collective Adaptive Systems (CASs): large-scale collections of relatively simple agents that act and coordinate with no central orchestrator to support distributed applications. Engineering global behaviour out of local activity and interaction, however, is a difficult task, typically addressed by try-and-error approaches in simulation environments. In the context of Aggregate Computing (AC), a prominent functional programming approach for CASs based on field-based coordination, this difficulty is reflected in the design of versatile algorithms preserving efficiency in a variety of environments. To deal with this complexity, in this work we propose to apply Machine Learning techniques to automatically devise local actions to improve over manually-defined AC algorithms specifications. Most specifically, we adopt a Reinforcement Learning-based approach to let a collective learn local policies to improve over the standard gradient algorithm—a cornerstone brick of several higher-level self-organisation algorithms. Our evaluation shows that the learned policies can speed up the self-stabilisation of the gradient to external perturbations

Matrix factorizations for quantum complete intersections

We introduce twisted matrix factorizations for quantum complete intersections of codimension two. For such an algebra, we show that in a given dimension, almost all the indecomposable modules with bounded minimal projective resolutions correspond to such matrix factorizations.Comment: 13 page

Spontaneous internal desynchronization of locomotor activity and body temperature rhythms from plasma melatonin rhythm in rats exposed to constant dim light

BACKGROUND: We have recently reported that spontaneous internal desynchronization between the locomotor activity rhythm and the melatonin rhythm may occur in rats (30% of tested animals) when they are maintained in constant dim red light (LL(dim)) for 60 days. Previous work has also shown that melatonin plays an important role in the modulation of the circadian rhythms of running wheel activity (R(w)) and body temperature (T(b)). The aim of the present study was to investigate the effect that desynchronization of the melatonin rhythm may have on the coupling and expression of circadian rhythms in R(w )and T(b). METHODS: Rats were maintained in a temperature controlled (23–24°C) ventilated lightproof room under LL(dim )(red dim light 1 μW/cm(2 )[5 Lux], lower wavelength cutoff at 640 nm). Animals were individually housed in cages equipped with a running wheel and a magnetic sensor system to detect wheel rotation; T(b )was monitored by telemetry. T(b )and R(w )data were recorded in 5-min bins and saved on disk. For each animal, we determined the mesor and the amplitude of the R(w )and T(b )rhythm using waveform analysis on 7-day segments of the data. After sixty days of LL(dim )exposure, blood samples (80–100 μM) were collected every 4 hours over a 24-hrs period from the tail artery, and serum melatonin levels were measured by radioimmunoassay. RESULTS: Twenty-one animals showed clear circadian rhythms R(w )and T(b), whereas one animal was arrhythmic. R(w )and T(b )rhythms were always strictly associated and we did not observe desynchronization between these two rhythms. Plasma melatonin levels showed marked variations among individuals in the peak levels and in the night-to-day ratio. In six rats, the night-to-day ratio was less than 2, whereas in the rat that showed arrhythmicity in R(w )and T(b )melatonin levels were high and rhythmic with a large night-to-day ratio. In seven animals, serum melatonin levels peaked during the subjective day (from CT0 to CT8), thus suggesting that in these animals the circadian rhythm of serum melatonin desynchronized from the circadian rhythms of R(w )and T(b). No significant correlation was observed between the amplitude (or the levels) of the melatonin profile and the amplitude and mesor of the R(w )and T(b )rhythms. CONCLUSION: Our data indicate that the free-running periods (τ) and the amplitude of R(w )and T(b )were not different between desynchronized and non-desynchronized rats, thus suggesting that the circadian rhythm of serum melatonin plays a marginal role in the regulation of the R(w )and T(b )rhythms. The present study also supports the notion that in the rat the circadian rhythms of locomotor activity and body temperature are controlled by a single circadian pacemaker

Video monitoring of Sparidae temporal rhythms: three-year study by OBSEA cabled observatory

The abundance and composition of fish assemblages varies at different temporal scales as a product of diel and annual rhythms. In this study, we used a video-wired observatory (OBSEA, www.obsea.es) to monitor annual rhythms in a coastal fish assemblage with a 3-year data set (2012-2014). The photographs were acquired at 30 min frequency. Five species of the family Sparidae were studied (i.e. Dentex dentex, Diplodus sargus, Diplodus vulgaris, Diplodus annularis and Diplodus puntazzo) together with water temperature and daylength. The results of the annual rhythmicity analysis indicated that most of the peaks of abundance occured in the autumn months. Results suggest differentially temporal use of the reproductive or trophic niche.Peer ReviewedPostprint (published version

A field-based computing approach to sensing-driven clustering in robot swarms

Swarm intelligence leverages collective behaviours emerging from interaction and activity of several “simple” agents to solve problems in various environments. One problem of interest in large swarms featuring a variety of sub-goals is swarm clustering, where the individuals of a swarm are assigned or choose to belong to zero or more groups, also called clusters. In this work, we address the sensing-based swarm clustering problem, where clusters are defined based on both the values sensed from the environment and the spatial distribution of the values and the agents. Moreover, we address it in a setting characterised by decentralisation of computation and interaction, and dynamicity of values and mobility of agents. For the solution, we propose to use the field-based computing paradigm, where computation and interaction are expressed in terms of a functional manipulation of fields, distributed and evolving data structures mapping each individual of the system to values over time. We devise a solution to sensing-based swarm clustering leveraging multiple concurrent field computations with limited domain and evaluate the approach experimentally by means of simulations, showing that the programmed swarms form clusters that well reflect the underlying environmental phenomena dynamics

Evaluation of anti-inflammatory and immunoregulatory activities of Stimunex® and Stimunex D3® in human monocytes/macrophages stimulated with LPS or IL-4/IL-13

Macrophages exert an important role in maintaining and/or ameliorating the inflammatory response. They are involved in the activation of an immune response to pathogens, with a balance between the immunomodulatory role and tissue integrity maintenance, however, excessive macrophage activity promotes tissue injury and chronic disease pathogenesis. There is a high interest in evaluating the anti-inflammatory properties of new botanical preparations. Stimunex® and Stimunex D3® are two food supplements formulated as syrups, containing the extract of elderflower (Sambucus nigra, Caprifoliaceae), standardized in polyphenol (6%) and anthocyanins (4%), associated with wellmune WGP® β-glucan, with the addiction of vitamin D3 (in Stimunex D3® formulation). The aim of the work was the evaluation of Stimunex® and Stimunex D3® activity in human polarized-macrophages, in order to support their use as supplement for preventing and reducing the inflammatory processes. In primary human stimulated macrophages, both syrups were able to revert LPS- and IL-4/IL-13-mediated response, reducing the release of several pro-inflammatory cytokines. Results support that these standardized botanical preparations fortified with β-glucan, may have a potential use in the prevention and coadjuvant management of inflammatory process as respiratory recurrent infections and other similar conditions. Moreover, the addition of vitamin D3 revealed to be an advantage in Stimunex D3® for its important role in maintaining and enhancing the innate immune response

Diseño de una guía de prácticas de laboratorio de acuerdo con las orientaciones del EEES

La adaptación de la docencia universitaria al Espacio Europeo de Educación Superior (EEES) supone un cambio en los sistemas de enseñanza actual. En este sentido el desarrollo de guías de laboratorio capaces de informar al alumnado, y normalizar la confección y presentación de las prácticas de laboratorio, asegurando una mejor calidad de la docencia y coordinación entre grupos, viene a cumplir con algunos de los objetivos pretendidos en el contexto de la Convergencia Europea. La Guía que se presenta, destinada a su empleo en la docencia práctica de una asignatura troncal de la licenciatura en Farmacia en la Universidad de Granada, recoge las indicaciones necesarias para llevar a cabo un trabajo seguro y eficiente en los laboratorios