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Costa CAS, Oliveira MF, Giro EMA, Hebling J. Biocompatibility of resin-based materials used as pulp-capping agents. International Endodontic Journal, 36, 831–839, 2003. To evaluate and compare the response of pulps of rats capped with resin-modified glass-ionomer cement (RMGIC) or self-etching adhesive system. Class I cavities were prepared on the occlusal surface of 54 maxillary first molars of 27 rats. Pulp exposure was performed on the cavity floor. The following resin-based materials were applied as pulp-capping agents: G1, Clearfil Liner Bond 2V (CLB 2V; Kuraray Co., Japan); G2, Vitrebond (VIT; 3M/ESPE, USA). In group 3 (control group), a calcium hydroxide/saline paste (CH; Labsynth, Brazil) was used. The cavities were restored with amalgam. After 7, 30 and 60 days, the animals were sacrificed and the jaws were processed for microscopic evaluation. Despite the inflammatory response caused by the experimental and the control materials at 7 days, pulpal healing associated with calcified barrier formation was observed at 60 days following the pulp therapy. Both resin-based materials promoted a large zone of cell-rich fibrodentine matrix deposition on the pulp horn related to the pulp exposure site, which was larger to VIT than to CLB 2V specimens. Tertiary dentine underneath the fibrodentine matrix was deposited by a layer of elongated pulpal cells. The remaining pulpal tissue exhibited normal histological characteristics. In the control group, healing and dentine-bridge formation was observed at 30 days. Pulpal breakdown occurred only when bacterial infection occurred. Both experimental pulp-capping agents allowed pulpal healing characterized by cell-rich fibrodentine and tertiary dentine deposition as well as calcified barrier formation. [ABSTRACT FROM AUTHOR]

In the last decade the Osservatorio Astronomico di Brera of the Italain Institute for Astrophysics, INAF, got deeply involved in Cherenkov optics manufacturing and testing, contributing to the realization of mirrors for MAGIC and CTA projects. In this contribution we review the characterization facilities that INAF-OAB developed to qualify the performance of Cherenkov mirrors. The design of these facilities was driven by the general Cherenkov optics configuration, realized with a large number of mirrors with arc-minutes resolution. The capability to obtain arc-minutes resolution characterization in a short measuring time is hence a driving concept for an efficient Cherenkov mirror qualification facility. The first facility implemented by INAF-OAB for Cherenkov optics is an outdoor 2f optical bench. Nevertheless, the 2f optical method permits to manage exclusively focusing optics. On the other hand, the introduction of novel optical design for Cherenkov telescopes, like the Schwarzschild–Couder design, creates the necessity to qualify free-form non-focusing optics. For this reason the INAF-OAB developed a flexible deflectometry setup capable to qualify any kind of Cherenkov optics. In this contribution we will describe these facilities, present some measurement results and discuss the wide range of possible applications they offer. • Qualification facilities developed at INAF-OAB for Cherenkov mirrors qualification. • Optical facility working in 2f configuration for the study of spherical mirrors PSF. • Deflectometry facility for free-form mirrors surface metrology. [ABSTRACT FROM AUTHOR]

Periodontal disease (PD) is induced by a complex microbiota, such as Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola (together called the red complex), which triggers intense inflammatory reaction. Down syndrome (DS) individuals demonstrate a high prevalence of PD compared with those who are otherwise chromosomally normal (euploids). This pilot study aimed to evaluate the effect of non-surgical periodontal treatment in DS chronic periodontitis patients on clinical and microbiological parameters. Patients with chronic periodontitis, 23 DS and 12 euploids (control group), were submitted to non-surgical mechanical periodontal treatment, followed by maintenance for 45 days. Clinical parameters after periodontal treatment were similar in diseased and healthy sites, independent of the genetic background. Diseased sites of DS and control patients harbored similar levels of P. gingivalis and T. forsythia at baseline, but significantly higher levels of T. denticola were found in DS patients. Increased levels of P. gingivalis at healthy sites were found in DS individuals. Non-surgical periodontal therapy decreased the levels of red complex microorganisms and improved the tested clinical parameters of diseased sites in both groups. However, the levels of red complex bacteria were higher in diseased sites of DS patients after the periodontal treatment. We conclude in this pilot study that, although the mechanical periodontal treatment seemed to be effective in DS subjects over a short-term period, the red complex bacteria levels did not decrease significantly in diseased sites, as occurred in controls. Therefore, for DS patients, it seems that the conventional non-surgical periodontal therapy should be improved by utilizing adjuvants to reduce the presence of periodontopathogens. [ABSTRACT FROM AUTHOR]

We describe a new polarimetric facility available at the Istituto Nazionale di AstroFisica / Telescopio Nazionale Galileo at La Palma, Canary islands. This facility, PAOLO (Polarimetric Add-On for the LRS Optics), is located at a Nasmyth focus of an alt-az telescope and requires a specific modeling in order to remove the time- and pointing position-dependent instrumental polarization. We also describe the opto-mechanical structure of the instrument and its calibration and present early examples of applications. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The Antarctic Multi-band Infrared Camera is a NIR/MIR double armed camera operating in the K, L, M, N, Q photometrical bands that will be mounted at one of the F/21.65 IRAIT Nasmyth foci (Tosti et al. 2006; Dolci et al. 2009). AMICA will host two detectors: the short wavelength radiation, 1 - 5.5 μm NIR band, is sensed by a Raytheon CRC-463 InSb 256×256 detector, while the long wavelengths 7 - 25 μm MIR band - is served by a DRS Technologies BIB Si:As 128 × 128 pixels array optimized for moderate photon flux. A fully reflective optical system, composed of two off-axis parabolic mirrors and one fixed 45? flat mirror, achieves a common, optimized, focal ratio reduction to F/14.73 at the detectors focal plane. Taking advantage from the large difference in pixel size between the NIR/MIR detectors, the resulting field-of-view will be 2.29 × 2.29 arcmin2 and 2.87 × 2.87 arcmin2 on the NIR and MIR array, respectively. In the present paper we report on the successful tests of the NIR/ MIR multiplexers functionality at the maximum required readout frequency. [ABSTRACT FROM AUTHOR]

This paper describes the results obtained so far with AquEYE, a single photon counting, fixed aperture photometer for the Asiago 182 cm telescope. AquEYE has been conceived as a prototype of a truly 'quantum' photometer for future Extremely Large Telescopes of 30-50 m aperture. This prototype is characterized by four independent channels equipped with single photon avalanche diodes (SPADs) as detectors. The counts from the four channels are acquired by a TDC board which has a nominal 25 ps time tagging capability. Taking into account the 35 ps jitter in the SPAD itself, the overall precision of the time tags is of the order of 50 ps. The internal oscillator is locked to an external rubidium clock; a GPS pulse per second is collected by the TDC itself to obtain a UTC reference. The maximum photon count rate which the present system can sustain is 12 MHz. [ABSTRACT FROM AUTHOR]

Abstract: The atmospheric Cherenkov telescope MAGIC for ground-based gamma-ray astronomy is operating since late 2003 on the Canary island of La Palma. Its 17m diameter mirror is composed of 964 square all-aluminum mirrors of side, making up a parabola of 236m2 area. Each mirror is composed of a sandwich of two thin aluminum layers interspaced by a honeycomb structure that ensures rigidity, high temperature conductivity and low weight. The surface of each raw blank is diamond milled to provide high reflectivity and a slightly different focal length to fit the overall parabolic shape of the reflector. We report about the stability and performance of the surface exposed to the atmosphere for over 3 years. For the construction of the clone of the first telescope, dubbed MAGIC II, major improvements of the design and performance of the reflective surface were required. Given the good experience with aluminum mirrors, a similar assembly was tested, but the area was increased to 1m2, which allowed to skip the inter-alignment of four mirrors within a panel and to reduce substantially the weight. The increased rigidity of the mirror unit resulted in an improved focussing quality. In addition, a second class of mirrors will be installed in the outermost part of the reflector, namely glass mirrors obtained by cold-slumping replica technique. Details on the construction of both type MAGIC II new mirrors and the 17m reflector will be presented. [Copyright &y& Elsevier]

Objective: The aim of this in vivo study was to evaluate the response of the pulp-dentin complex following application of resin-modified glass-ionomer cement, calcium hydroxide hard-setting cement and EDTA-soluble preparation of dentine matrix proteins (ESDP) in deep cavities prepared in non-human primate teeth. Methods: Eighteen deep Class V buccal cavities were prepared in premolars of four capuccin monkeys. In Groups 1 and 2, the cavity floor was lined with ESDP or a resin-modified glass-ionomer cement (Vitrebond - 3M ESPE), respectively. In Group 3 (control), the cavity was lined with a hard setting calcium hydroxide cement (Dycal - Dentsply). The cavities were subsequently filled with amalgam. After 6 months, the animals were sacrificed and the teeth were prepared for microscopic assessment. Six-micron thick serial sections were stained with H/E, Masson's trichrome and Brown & Brenn techniques. Results: No inflammatory pulpal response was observed for all experimental and control Groups. However, the amount of reactionary dentin deposition differed between groups in the rank order ESDP (Group 1) > calcium hydroxide (Group 3) > resin-modified glass-ionomer (Group 2). These differences were statistically significant. Conclusions: All materials were biocompatible when applied in deep cavities. ESDP stimulated higher deposition of reactionary dentin matrix than Vitrebond and Dycal. [ABSTRACT FROM AUTHOR]

The photochromic properties of transparent/opaque transition and the change of the refractive index (?n) have been exploited to develop devices for astronomical spectrographs, both as focal plane masks and as dispersive elements (volume phase holographic gratings, VPHGs), respectively. In both cases the possibility to write and erase with suitable irradiation has revealed a new perspective for non-disposable and fully customisable items for spectroscopy. High contrast focal plane masks based on the photochromism of poly-1,2-bis(2-methyl-3-thienyl)perfluorocyclopentene have been obtained. Concerning the use of photochromic molecules as dispersing elements, low molecular weight diarylethenes and diarylethenes polymers have been considered and ellipsometric measurements were carried out to determine the refractive index change which accompanies the photochromic process. [ABSTRACT FROM AUTHOR]

We report on a spectropolarimetric analysis of four southern ultraluminous infrared galaxies (ULIRGs), aimed at constraining the presence of hidden broad active galactic nucleus (AGN) lines. For IRAS 19254-7245 (The Superantennae) we find evidence for a significant level of polarized light in the Hα line with FWHM > 2300 km s[sup -1]. Some degree of polarization is also detected in IRAS 20551-4250, though with lower significance. In the two other sources (IRAS 20100-4156 and IRAS 22491-1808) no polarized signals are detected. Although it is unclear from the present data if the origin of polarization is due to reflected light from an AGN or more simply to dichroic transmission by a dust slab, we find interesting correlation between the presence of polarized components in the optical spectra and independent evidence for AGN emissions in hard X-rays and the far-IR. [ABSTRACT FROM AUTHOR]