Status of NEMO: results from the NEMO Phase-1 detector

The NEMO Collaboration installed an underwater detector including most of the critical elements of a possible km$^3$ neutrino telescope: a four-floor tower (called Mini-Tower) and a Junction Box, including the data transmission, the power distribution, the timing calibration and the acoustic positioning systems. These technical solutions will be evaluated, among others proposed for the construction of the km$^3$ detector, within the KM3NeT Consortium. The main test of this test experiment was the validation of the proposed design solutions mentioned above. We present results of the analysis of data collected with the NEMO Mini-Tower. The position of PMTs is determined through the acoustic position system; signals detected with PMTs are used to reconstruct the tracks of atmospheric muons. The angular distribution of atmospheric muons was measured and results were compared with Monte Carlo simulations.Comment: Proc. of CRIS 200

Contributors

Biographical information on contributors to volume 40, and a list of benefactors and donor

Dynamical Properties of Heavy-Ion Collisions from the Photon-Photon Intensity Correlations

We consider here the bremsstrahlung emission of photons at low and intermediate energies $E_{lab}\le 1000 MeV/u$ of the projectile. and derive expressions more general than previous results obtained by Neuhauser which were limited to the case of isotropic systems. We find that the two-photon correlation function strongly depends not only on the space-time properties of the collision region but also on the dynamics of the proton-neutron scattering process in nuclear matter. As a consequence of polarisation correlations it turns out that for a purely chaotic source the intercept of the correlation function of photons can reach the value $3$ (as compared with the maximum value $2$ for isotropic systems). Furthermore even for ``hard" photons ($E_{\gamma} > 25 MeV$) the maximum of the correlation function can reach the value of $2$ in contrast with the value of $1.5$ derived by Neuhauser for this case. The formulae obtained in this paper which include also the possible presence of a coherent component can be used as a basis for a systematic analysis of photon intensity-interferometry experiments.Comment: 12 pages, LaTeX, DMR-THEP-93-2/

Table of Contents and Prologue

Editorial board, table of contents, and a prologue from the editor

Intermolecular interaction and solid state characterization of abietic acid/chitosan solid dispersions possessing antimicrobial and antioxidant properties

The aim of this work was to prepare and characterize solid dispersions of abietic acid (AB) and chitosan (CS) to investigate how formulation of the mixture may help in the battle against microbial colonization in different areas, such as the biomedical field or the food industry. Solid dispersions were characterized by differential scanning calorimetry, infrared spectroscopy, Raman spectroscopy, polarized optical microscopy, zeta potential and size analysis. The data showed that the dispersion/solvent evaporation method formed solid dispersions in which abietic acid was molecularly dispersed in the carrier. A synergistic effect between the two components in terms of antioxidant and antimicrobial properties was found, especially in the formulations obtained with 1/1 AB/CS molar ratio. Interestingly, the aggregation state (amorphous/crystalline) of AB seemed to affect the antimicrobial activity of the formulation, suggesting increased bioactivity when the drug was in the amorphous state. These findings, together with the demonstrated biocompatibility of the formulations, seem to open promising perspectives for a successful application of the developed AB/CS formulations in the biomedical field or in the food industry

Underwater Laboratories for Astroparticle Physics and Deep Sea Science

The exploration of deep sea environments is presently at the dawn of a new era: underwater laboratories, permanently installed on the sea floor and offering power and on-line data transmission links to the shore, will allow to continuously monitor oceanographical properties. An important boost in this direction has been provided by the high energy physics scientific community, that aims at the realization of an underwater detector for cosmic high energy neutrinos. Neutrinos are considered a very promising probe for high energy astrophysics and many indications suggest that some of the most energetic sources known in the universe could also be high energy neutrino sources. The expected neutrino fluxes indicate that a km3-scale detector must be realised to achieve this ambitious aim. The quest for the realization of such a detector in the Mediterranean Sea has already started

A guided walk through the world of mesoporous bioactive glasses (MBGs): Fundamentals, processing, and applications

Bioactive glasses (BGs) are traditionally known to be able to bond to living bone and stimulate bone regeneration. The production of such materials in a mesoporous form allowed scientists to dramatically expand the versatility of oxide-based glass systems as well as their applications in biomedicine. These nanostructured materials, called mesoporous bioactive glasses (MBGs), not only exhibit an ultrafast mineralization rate but can be used as vehicles for the sustained delivery of drugs, which are hosted inside the mesopores, and therapeutic ions, which are released during material dissolution in contact with biological fluids. This review paper summarizes the main strategies for the preparation of MBGs, as well as their properties and applications in the biomedical field, with an emphasis on the methodological aspects and the promise of hierarchical systems with multiscale porosity

Progress and latest results from Baikal, Nestor, NEMO and KM3NeT

Neutrinos are considered promising probes for high energy astrophysics. Deep water/ice Cerenkov technique was proposed to detect high energy neutrinos. According to present estimates, km3 scale detectors are needed to detect high energy neutrinos from cosmos. IceCube neutrino telescope is under construction in the South Pole. For a full sky observation, a second km3 telescope is required. In this paper progress and latest results from Baikal, NESTOR and NEMO experiments, operating in the Northern hemisphere are reviewed. KM3NeT status and activities toward a km3 telescope in the Mediterranean Sea is also presented

Comparison between bioactive sol-gel and melt-derived glasses/glass-ceramics based on the multicomponent SiO2-P2O5-CaO-MgO-Na2O-K2O System

Bioactive sol-gel glasses are attractive biomaterials from both technological and functional viewpoints as they require lower processing temperatures compared to their melt-derived counterparts and exhibit a high specific surface area due to inherent nanoporosity. However, most of these materials are based on relatively simple binary or ternary oxide systems since the synthesis of multicomponent glasses via sol-gel still is a challenge. This work reports for the first time the production and characterization of sol-gel materials based on a six-oxide basic system (SiO2-P2O5-CaO-MgO-Na2O-K2O). It was shown that calcination played a role in inducing the formation of crystalline phases, thus generating glass-ceramic materials. The thermal, microstructural and textural properties, as well as the in vitro bioactivity, of these sol-gel materials were assessed and compared to those of the melt-derived counterpart glass with the same nominal composition. In spite of their glass-ceramic nature, these materials retained an excellent apatite-forming ability, which is key in bone repair applications