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Presentation on Hierarchical Optimal Sampling: a tool for managing and manipulating wide-field imaging datasets. Powerful recording techniques and increasing anatomical knowledge provided by atlases allow studying the brain at a new level with unprecedented spatial resolution as that achieved with wide-field calcium imaging data. One of the the main issues related to the increase of the spatial resolution is to find the optimal condition which allows to obtain an appropriate signal-to-noise ratio for each channel, relative to the phenomenon of interest. Hierarchical Optimal Sampling (HOS) provides a data-driven inhomogeneous gridding of the field of view with the optimal spatial resolution that preserves and emphasizes the majority of the information from the high number of native signal sources.

Flash talk presented at the workshop "Brain Activity across Scales and Species: Analysis of Experiments and Simulations"

The brain exhibits capabilities of fast incremental learning from a few noisy examples, as well as the ability to associate similar memories in autonomously-created categories and to combine contextual hints with sensory perceptions. Together with sleep, these mechanisms are thought to be key components of many high-level cognitive functions. Yet, little is known about the underlying processes and the specific roles of different brain states. In this work, we exploited the combination of context and perception in a thalamo-cortical model based on a soft winner-take-all circuit of excitatory and inhibitory spiking neurons. After calibrating this model to express awake and deep-sleep states with features comparable with biological measures, we demonstrate the model capability of fast incremental learning from few examples, its resilience when proposed with noisy perceptions and contextual signals, and an improvement in visual classification after sleep due to induced synaptic homeostasis and association of similar memories., This work has been supported by the European Union Horizon 2020 Research and Innovation program under the FET Flagship Human Brain Project (grant agreement SGA3 n. 945539 and grant agreement SGA2 n. 785907) and by the INFN APE Parallel/Distributed Computing laboratory.

Wakefulness and sleep are brain-states that are essential for cognitive performances. During wakefulness, our perceptual system is continuously subjected to sensory inputs from different sources and modalities. The involved brain areas process the input in a framework set by previous knowledge (acquired through individual and evolutionary experience) with a crucial role played by the exchange of signals with other brain areas. The ability of the brain to integrate and segregate this information by building a coherent and complete representation of the environment is impressive. Despite there is plenty of empirical evidence suggesting that the nervous system uses a statistically optimal approach in combining external information, little is known about how the brain implements these strategies. Moreover, recent studies have shown that sleep plays a central role in storing and reorganizing information gained while awake and in the optimization of the energetic post-sleeping rates. Starting from these results and a recent simplified single area thalamo-cortical model, our work focuses on two main issues. First, we aim to simulate the ability of the awake brain to combine different kinds of information, throughout multisensory perception, with contextual information starting from the case of the integration of the two visual hemicampi that in the brain are processed by areas placed in two different hemispheres. Second, we study the beneficial effects of a deep-sleep-like biologically plausible slow oscillation activity on the classification accuracy. In summary, in this work, we create a simplified thalamo-cortical multi-area simulation model trained to learn, sleep and perform a classification task on handwritten digits., {"references":["Capone, C., Pastorelli, E., Golosio, B., and Paolucci, P. S. \"Sleep-like slow oscillations improve visual classification through synaptic homeostasis and memory association in a thalamo-cortical model.\" Scientific Reports, 9 (2019), 8990.","Larkum, M. E. \"A cellular mechanism for cortical associations: an organizing principle for the cerebral cortex.\", Trends in Neurosciences, 36 (2013), 141"]}

The discovery of cosmic neutrinos of astrophysical origin by IceCube has started a new chapter in the field of Neutrino Astronomy. Noticeably, a small accumulation of events in the region near the Galactic Centre has been observed: a telescope in the Mediterranean Sea constitutes a great opportunity for the physics quest, since it offers a perfect complementarity to IceCube and, in particular, a better visibility of the Galactic Centre. ANTARES (Astronomy with a Neutrino Telescope and Abyss Environmental RESearch) is the first operational Cherenkov neutrino telescope in the Mediterranean Sea and the largest neutrino detector in the Northern hemisphere, covering an area of about 0.1 km2; located 40 km offshore Toulon, France, at a depth of 2475 m, it has been completed in June 2008 and it is currently taking data. It consists of a tri-dimensional array of 885 photo-multipliers tubes (PMTs), distributed in 12 lines. ANTARES has recently performed a search for an excess of high energy neutrinos in the direction of the Galactic Centre, close to the accumulation of the IceCube events, assuming both the hypotheses of a point-like and an extended neutrino source. The results of this search will be discussed in this contribution, together with other recent achievements of the experiment, as the search for point-like sources, the results on the diffuse flux of cosmic neutrino signal and the search for neutrino emission from the Fermi bubbles. ANTARES offers a first view of the Neutrino Sky from the Northern hemisphere; its successful operation and its promising results make more compelling the expectations for KM3NeT, the next generation neutrino experiment in the Mediterranean Sea.

In the framework of Horizon 2020, the European Commission approved the ASTERICS initiative (ASTronomy ESFRI and Research Infrastructure CluSter) to collect knowledge and experiences from astronomy, astrophysics and particle physics and foster synergies among existing research infrastructures and scientific communities, hence paving the way for future ones. ASTERICS aims at producing a common set of tools and strategies to be applied in Astronomy ESFRI facilities. In particular, it will target the so-called multi-messenger approach to combine information from optical and radio telescopes, photon counters and neutrino telescopes. pLISA is a software tool under development in ASTERICS to help and promote machine learning as a unified approach to multivariate analysis of astrophysical data and signals. The library will offer a collection of classification parameters, estimators, classes and methods to be linked and used in reconstruction programs (and possibly also extended), to characterize events in terms of particle identification and energy. The pLISA library aims at offering the software infras tructure for applications developed inside different experiments and has been designed with an effort to extrapolate general, physics-related estimators from the specific features of the data model related to each particular experiment. pLISA is oriented towards parallel computing architectures, with awareness of the opportunity of using GPUs as accelerators demanding specifically optimized algorithms and to reduce the costs of pro cessing hardware requested for the reconstruction tasks. Indeed, a fast (ideally, real-time) reconstruction can open the way for the development or improvement of alert systems, typically required by multi-messenger search programmes among the different experi mental facilities involved in ASTERICS.

Huge sensitive volumes will be required to identify interactions of U.H.E. cosmic neutrinos with energy above 1016eV. New detectors and new techniques have to be developed to open this future field of H.E. astrophysics. We report on the study of acoustic signals induced by the interaction in water of a high intensity low energy proton beam (ITEP, Moscow). Acoustic signals have been collected by means of high sensitivity deep-sea hydrophones, for proton energy deposition close to 0.1 Joule. Hydrophones sensitivity has been previously characterized at the acoustic test facilities of IDAC-CNR (Rome). Results show a good linearity between the proton beam intensity and the hydrophones signal amplitude. Results are encouraging for the future detection of highenergy neutrino-induced showers developing in deep-sea water.

A 13-inch Optical Module (OM) containing a large-area (10-inch) photomultiplier was designed as part of Phase-2 of the NEMO project. An intense R&D activity on the photomultipliers, the voltage supply boards, the optical coupling as well as the study of the influences of the Earth's magnetic field has driven the choice of each single component of the OM. Following a well-established production procedure, 32 OMs were assembled and their functionality tested. The design, the testing and the production phases are thoroughly described in this paper. © 2013 IOP Publishing Ltd and Sissa Medialab srl.

The NEMO (NEutrino Mediterranean Observatory) Collaboration installed, 25 km E offshore the port of Catania (Sicily) at 2000 m depth, an underwater laboratory to perform long-term tests of prototypes and new technologies for an underwater high energy neutrino km 3 -scale detector in the Mediterranean Sea. In this framework the Collaboration deployed and successfully operated for about two years, starting from January 2005, an experimental apparatus for on-line monitoring of deep-sea noise. The station was equipped with four hydrophones and it is operational in the range 30 Hz–43 kHz. This interval of frequencies matches the range suitable for the proposed acoustic detection technique of high energy neutrinos. Hydrophone signals were digitized underwater at 96 kHz sampling frequency and 24 bits resolution. The stored data library, consisting of more than 2000 h of recordings, is a unique tool to model underwater acoustic noise at large depth, to characterize its variations as a function of environmental parameters, biological sources and human activities (ship traffic, etc.), and to determine the presence of cetaceans in the area.

The first implementation of the KM3NeT-IT neutrino telescope consists in the installation of 24 Strings and 8 Towers. Focusing on the Towers, the idea behind this work is to exploit the LED sources mounted in the OMs to develop a complementary system, on shore and before the deployment, for the determination of time delays, aiming at the characterizations of the time response of the different elements of the detector. During the assembling of the first tower, a set of measurements has been carried out; the test set-up and the measurement procedure are described, together with preliminary results of the calibration system. Lesson learnt is quite encouraging: uncertainties of the order of 400 ps are reached with very few cautions taken during the short calibration session, and with large room for improvement, making this system feasible and effective for the KM3NeT-IT experiment.

One of the tasks of an electronic system designed to monitor environmental parameters is to provide the user with a point-to-point connection to several remotely located instruments and probes. In this paper, we describe in detail the electronics developed to fulfill this task. Environmental parameters generally vary slowly in time such that the overall data rate needed to monitor their time dependency do not exceed few tens of kb/s. For this reason, we called the electronic board devoted to their monitoring ‘Slow Control Interface’.

The ANTARES neutrino telescope is currently the largest operating water Cherenkov detector and the largest neutrino detector in the Northern Hemisphere. Its main scientific target is the detection of high-energy (TeV and beyond) neutrinos from cosmic accelerators, as predicted by hadronic interaction models, and the measurement of the diffuse neutrino flux. Its location allows for surveying a large part of the Galactic Plane, including the Galactic Centre. In addition to the standalone searches for point-like and diffuse high-energy neutrino signals, ANTARES has developed a range of multi-messenger strategies to exploit the close connection between neutrinos and other cosmic messengers such as gamma-rays, charged cosmic rays and gravitational waves. This contribution provides an overview of the recently conducted analyses, including a search for neutrinos from the Fermi bubbles region, searches for optical counterparts with the TAToO program, and searches for neutrinos in correlation with gamma-ray bursts, blazars, and microquasars. Further topics of investigation, covering e.g. the search for neutrinos from dark matter annihilation, searches for exotic particles and the measurement of neutrino oscillations, are also reviewed., Comment: 8 pages, 9 figures. Prepared for the Proceedings of RICAP-13 Roma International Conference on Astroparticle Physics (Rome, 22-24 May 2013); to appear in Nucl. Instr. Meth. A Procs. Suppl