The KM3NeT Project

The KM3NeT research infrastructure in the deep Mediterranean Sea will host a multi-cubic-kilometre neutrino telescope and provide connectivity for continuous, long-term earth and sea science measurements. The KM3NeT neutrino telescope will complement the IceCube telescope at the South Pole in its field of view and surpass it substantially in sensitivity. In this paper the status of the KM3NeT activities is presented

Ghost cells in compound odontoma: a study of undemineralized material

Calcifications and ghost cells at the enamel surface or in the ameloblastic epithelium were studied in twelve odontomas using undemineralized material.Calcified material formed focally in the intercellular portion of the enamel epithelium: this material showed a concentric layers arrangement.Ghost cells were present in most of the odontomas.These ghost cells were epithelial cells which enlarged, became eosiniphilic and underwent an aberrant type of keratinization with the formation of large masses of keratin, that didn’t stain as deeply as normal keratin. These cells often showed karyolysis of the nucleus as keratinization progressed. Frequent was the appearance of dystrophic calcifications in individual cells or clusters of cells, characterized by extremely fine basophilic granularity. The outlines of these keratinized cells could often still be discerned, even if with some difficulty.Les calcifications et les cellules fantômes à la surface de l’émail ou dans l’épithélium améloblastique ont été étudiées dans 12 odontomes en utilisant du matériel non décaldfié.Le matériel calcifié est formé focalement dans les portions intercellulaires de l'épithélium de l'émail: ce matériel montre un agencement en couches concentriques.Les cellules fantômes sont présentes dans la plupart des odontomes. Ces cellules fantômes sont des cellules épithéliales qui augmentent de taille, deviennent éosinophiles et subissent un type aberrant de kératinisation avec formation de larges masses de kératine qui ne se colorent pas aussi intensément que la kératine normale. Ces cellules montrent souvent une karyolyse du noyau au fur et à mesure de la progression de la kératinisation. Il était fréquent de rencontrer l’apparition de calcifications dystrophiques dans des cellules isolées ou en îlots, caractérisées par des granulations basophiles extrêmement fines. Les contours de ces cellules kératinisées peuvent être encore souvent discernés, quoique avec certaines difficultés

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

Light and Laser Scanning Microscopy analysis of hydroxyapatite used in periodontal osseous defects in man: evidence of a different resorption pattern in bone and soft tissues

Hydroxyapatite (HA) is a highly biocompatible material that recently has been shown to undergo biodegradation. The mechanisms of this phenomenon are unclear, and humoral and cellular events have been thought to be implicated. In the present study HA particles were put into infraosseous defects on teeth that were to be extracted for prosthetic reasons and then retrieved after a 1 year period. The specimens were processed with the cutting grinding system. Results show a very sharp difference of the biodegradation processes, related to the tissues that surround the HA particles. HA in tight contact with mineralized bone showed no evidence of degradation or resorption, while on the contrary, in the areas where bone loose connective tissue was present, it was possible to observe HA crystals detached and scattered in cells cytoplasm or extracellular fluids. This dissolution and resorption phenomenon were observed also by Laser Scanning Microscope (LSM) in fluorescent mode. These differences in degrees of degradation between bone and loose connective tissue could be due to the small amount of interstitial fluid present in mineralized bone and the greater flow of fluid through connective tissue.L’hydroxyapatite (HA) est un matériel hautement biocompatible qui s’est révélé récemment capable de subir une biodégradation. Le mécanisme de ce phénomène n’est pas clair, et semble impliquer une particination humorale et cellulaire. Notre recherche a porté sur la mise en place de particules d’HA dans des défects intraosseux en rapport avec des dents qui doivent être extraites pour des raisons prothésiques, et sur leur etude suite à leur ablation un an après. Les résultats ont démontré des différences marquées dans le processus de dégradation en rapport avec les tissus qui entourent l’HA. Les particules d’HA qui sont en contact avec l’os minéralisé ne présentent pas de signes de dégradation ou de résorption, tandis que dans les régions où du tissu conjonctif était présent, il est possible d’observer des cristaux d’HA détachés et dispersés dans le cytoplasme des cellules et dans le liquide extracellulaire. Ces phénomènes de dissolution et de résorption ont été également étudiés au Microscope Electronique à Balayage au Laser en fluorescence. Ces différences dans le degré de dégradation observés dans l’os et dans le tissu conjonctif lâche pourraient être dues à la faible quantité de liquide interstitiel dans l’os minéralisé et à la quantité plus grande de flux liquidien dans le tissu conjonctif

Randomised study for the 1-year crestal bone maintenance around modified diameter implants with different loading protocols: a radiographic evaluation.

This study evaluated by standardised digitised periapical radiography the crestal bone maintenance around modified diameter internal hex implants with variable thread design and narrow neck loaded with different procedures. Forty implants were placed in 25 patients. Twenty implants were conventionally loaded, 20 ones immediately loaded. Radiographs were taken with a customised bite record and processed with software. Measurements of bone from the fixture–abutment junction to mesial and distal marginal bone levels were made. Student’s t test statistical analysis was adopted. Baseline data were variable; at 1-year follow-up, there were no significant differences for marginal bone loss between immediately and conventionally loaded maxillary implants (p=0.1031), whilst there were slight significant differences between immediately and conventionally loaded implants in the mandible (p=0.0141). Crestal bone maintenance around conventionally and immediately loaded modified diameter implants was similar, with slight significant differences in mandible where a lower marginal bone loss was observed

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

Strong enhancement of extremely energetic proton production in central heavy ion collisions at intermediate energy

The energetic proton emission has been investigated as a function of the reaction centrality for the system 58Ni + 58Ni at 30A MeV. Extremely energetic protons (EpNN > 130 MeV) were measured and their multiplicity is found to increase almost quadratically with the number of participant nucleons thus indicating the onset of a mechanism beyond one and two-body dynamics.Comment: 5 pages, 2 figures, submitted to Physical Review Letter

Prompt dipole radiation in fusion reactions

The prompt gamma ray emission was investigated in the 16A MeV energy region by means of the 36,40Ar+96,92Zr fusion reactions leading to a compound nucleus in the vicinity of 132Ce. We show that the prompt radiation, which appears to be still effective at such a high beam energy, has an angular distribution pattern consistent with a dipole oscillation along the symmetry axis of the dinuclear system. The data are compared with calculations based on a collective bremsstrahlung analysis of the reaction dynamics

Dark matter searches using superheated liquids

Direct detection of dark matter is one of the most important topics in modern physics. It is estimated that 22% of universe matter is composed by dark matter in front of 0.4% of ordinary matter like stars, galaxies planets and all kind of known astrophysical objects. Several kinds of experiments are nowadays involved in detection of one of the more accepted particle candidates to be dark matter: WIMPs (Weakly Interacting Massive Particles). These detectors, using several kinds of techniques: Cryogenic semiconductors, scintillation materials like I Na or noble gas chambers among others, are reporting very interesting but inconclusive results. In this paper a review of detectors that are using the superheated liquid technique in bubble chambers in order to detect WIMPs is reported. Basically, we will report about Coupp (Chicagoland observatory for underground particle physics), PICO that is composed by Coupp and Picasso researchers having the aim to build a ton experiment and also about a new detector named MOSCAB (Materia oscura a bolle) that recently published a first results of a test chamber that uses also superheated liquid technique but as a Geyser chamber.Bou Cabo, M.; Ardid Ramírez, M.; Felis-Enguix, I. (2016). Dark matter searches using superheated liquids. EPJ Web of Conferences. 121(06007):1-8. doi:10.1051/epjconf/201612106007S1812106007Rayleigh L., On the pressure developed in a liquid during the collapse of a spherical cavity (Philos. Mag34, 94, 1917)Plesset M.S., The growth of vapor bubbles in superheated liquid (J. Appl. Phys.25, 9493, 1954)Forster H.K., Growth of vapor bubbles in superheated liquid (J. Appl. Phys.05, 474, 1954)Seitz F. (Phys. Fluids1, 2, 1958)Behnke E. et al., Coupp Collaboration, First dark matter search results from a 4-kg CF3I bubble chamber operated in a deep underground site (Phys. Rev. D86, 2012)Behnke et al., Coupp Collaboration, Direct measurement of the bubble-nucleation energy threshold in a CF3I bubble chamber (Phys. Rev. D88, 2013)Archambault S., Picasso Collaboration, Dark Matter Spin-Dependent Limits for WIMPs Interactions on19F by PICASSO(Phys. Lett. B, 2009)Bertoni R. et al., A new technique for direct investigation of dark matter (Nuclear Instruments and Methods in Physics Research, A, 61–68, 2014)Bou-Cabo M. et al., LOW Radioactivity Techniques 2013 (LRT 2013): Proceedings of the IV International Workshop in Low Radioactivity Techniques, V:1549, 142 – 147Ardid M. et al., MOSCAB: Direct dark matter search using the Geyser technique, Proc. ICHEP 2014 Conf., Nucl. Phys. B: Proc. Supp. (in press

Measuring diffuse neutrino fluxes with IceCube

In this paper the sensitivity of a future kilometer-sized neutrino detector to detect and measure the diffuse flux of high energy neutrinos is evaluated. Event rates in established detection channels, such as muon events from charged current muon neutrino interactions or cascade events from electron neutrino and tau neutrino interactions, are calculated using a detailed Monte Carlo simulation. Neutrino fluxes as expected from prompt charm decay in the atmosphere or from astrophysical sources such as Active Galactic Nuclei are modeled assuming power laws. The ability to measure the normalization and slope of these spectra is then analyzed. It is found that the cascade channel generally has a high sensitivity for the detection and characterization of the diffuse flux, when compared to what is expected for the upgoing- and downgoing-muon channels. A flux at the level of the Waxman-Bahcall upper bound should be detectable in all channels separately while a combination of the information of the different channels will allow detection of a flux more than one order of magnitude lower. Neutrinos from the prompt decay of charmed mesons in the atmosphere should be detectable in future measurements for all but the lowest predictions.Comment: 12 pages, 3 figure