The effect of different remineralizing agents on caries-like lesions – a pilot study

Poster apresentado no XXV Congresso da Ordem dos Médicos Dentistas, 10-12 Novembro 2016, Porto, PortugalSob uma licença CC-BY-NC - http://creativecommons.org/licenses/by-nc/4.0/Aim: To quantify the surface microhardness of enamel when using different remineralizing agents, after the induction of artificial dental caries.N/

Coding binary local features extracted from video sequences

Local features represent a powerful tool which is exploited in several applications such as visual search, object recognition and tracking, etc. In this context, binary descriptors provide an efficient alternative to real-valued descriptors, due to low computational complexity, limited memory footprint and fast matching algorithms. The descriptor consists of a binary vector, in which each bit is the result of a pairwise comparison between smoothed pixel intensities. In several cases, visual features need to be transmitted over a bandwidth-limited network. To this end, it is useful to compress the descriptor to reduce the required rate, while attaining a target accuracy for the task at hand. The past literature thoroughly addressed the problem of coding visual features extracted from still images and, only very recently, the problem of coding real-valued features (e.g., SIFT, SURF) extracted from video sequences. In this paper we propose a coding architecture specifically designed for binary local features extracted from video content. We exploit both spatial and temporal redundancy by means of intra-frame and inter-frame coding modes, showing that significant coding gains can be attained for a target level of accuracy of the visual analysis task

Making music for mental health: how group drumming mediates recovery

BACKGROUND: While music-making interventions are increasingly recognised as enhancing mental health, little is known of why music may engender such benefit. The objective of this article is to elucidate the features of a programme of group drumming known to enable mental health recovery. METHODS: Qualitative research was conducted with 39 mental health patients and carers who had demonstrated recovery following engagement with a programme of group djembe drumming in the UK. Data were collected through semi-structured individual interviews and focus group interviews designed to understand the connection between drumming and recovery and analysed using Interpretative Phenomenological Analysis (IPA). RESULTS: Results revealed three overarching features of the drumming intervention: (1) the specific features of drumming, including drumming as a form of non-verbal communication, as a connection with life through rhythm, and as a grounding experience that both generates and liberates energy; (2) the specific features of the group, including the group as a space of connection in and through the rhythmic features of the drumming, as well as facilitating feelings of belonging, acceptance, safety and care, and new social interactions; (3) the specific features of the learning, including learning as an inclusive activity in which the concept of mistakes is dissolved and in which there is musical freedom, supported by an embodied learning process expedited by the musical facilitator. CONCLUSION: The findings provide support for the conceptual notion of 'creative practice as mutual recovery', demonstrating that group drumming provides a creative and mutual learning space in which mental health recovery can take place

The Answer is Blowing in the Wind

A 'News & Views' article -- no abstract

Imaging the dense stellar cluster R136 with VLT-MAD

We evaluate the performance of the Multi-conjugate Adaptive optics Demonstrator (MAD) from H and Ks imaging of 30 Doradus in the Large Magellanic Cloud. Maps of the full-width half maximum (FWHM) of point sources in the H and Ks images are presented, together with maps of the Strehl ratio achieved in the Ks-band observations. Each of the three natural guide stars was at the edge of the MAD field-of-view, and the observations were obtained at relatively large airmass (1.4-1.6). Even so, the Strehl ratio achieved in the second pointing (best-placed compared to the reference stars) ranged from 15% to an impressive 30%. Preliminary photometric calibration of the first pointing indicates 5 sigma sensitivities of Ks=21.75 and H=22.25 (from 22 and 12 min exposures, respectively).Comment: 9 pages, 9 figures, to appear in "Adaptive Optics Systems", SPIE conference, Marseille, 23-28 June 2008. Full resolution version can be downloaded from http://www.roe.ac.uk/~mac/MAD.htm

The low-mass content of the massive young star cluster RCW 38

KM acknowledges funding by the Joint Committee of ESO/Government of Chile, and by the Science and Technology Foundation of Portugal (FCT), grant no. IF/00194/2015. Part of the research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no. [614922]. RJ acknowledges support from NSERC grants. JA acknowledges funding by the Science and Technology Foundation of Portugal (FCT), grant no. SFRH/BPD/101562/2014.RCW 38 is a deeply embedded young (∼1 Myr), massive star cluster located at a distance of 1.7 kpc. Twice as dense as the Orion nebula cluster, orders of magnitude denser than other nearby star-forming regions and rich in massive stars, RCW 38 is an ideal place to look for potential differences in brown dwarf formation efficiency as a function of environment. We present deep, high-resolution adaptive optics data of the central ∼0.5 × 0.5 pc2 obtained with NACO at the Very Large Telescope. Through comparison with evolutionary models, we determine masses and extinction for ∼480 candidate members, and derive the first initial mass function (IMF) of the cluster extending into the substellar regime. Representing the IMF as a set of power laws in the form dN/dM ∝ M−α, we derive the slope α = 1.60 ± 0.13 for the mass range 0.5–20 M⊙,which is shallower than the Salpeter slope, but in agreement with results in several other young massive clusters. At the low-mass side, we find α = 0.71 ± 0.11 for masses between 0.02 and 0.5 M⊙, or α = 0.81 ± 0.08 for masses between 0.02 and 1 M⊙. Our result is in agreement with the values found in other young star-forming regions, revealing no evidence that a combination of high stellar densities and the presence of numerous massive stars affects the formation efficiency of brown dwarfs and very-low-mass stars. We estimate that the Milky Way galaxy contains between 25 and 100 billion brown dwarfs (with masses >0.03 M⊙).Publisher PDFPeer reviewe