Arkitettura u ambjent : “Burning down the house to stay warm”

Nirringrazzjakom ta' din l-istedina għal dan id-dibattitu tassew importanti. Nispera li f'dawn il-ftit minuti jirnexxili nurikom perspettiva arkitettonika ta' konċerni li jien personali għandi għaII-futur tal-pajjiż għażiż tagħna. Meta wieħed iħares 'iI quddiem, ħafna drabi l-ewwel kelma li tiġi f'moħħu hija l-kelma "Progress". F'diversi films tal-futur, id-diretturi jirnexxilhom jagħtu impressjoni bil-progress u l-ħajja moderna tal-bniedem tal-futur. Fuq in-naħa l-oħra nsibu dawk il-kittieba illi jbeżżgħuna mill-futur, bħaII-awtur George OrweII fil-ktieb tiegħu "1984". Ħadd ma għandu jibża' miII-futur, imma wieħed irid joqgħod ferm attent biex fil-preżent nagħmlu deċiżjonijiet tajbin biex ma nagħmlux ħerba għaII-futur.peer-reviewe

Circulating cell-free DNA: Translating prostate cancer genomics into clinical care.

Only in the past decade tremendous advances have been made in understanding prostate cancer genomics and consequently in applying new treatment strategies. As options regarding treatments are increasing so are the challenges in selecting the right treatment option for each patient and not the least, understanding the optimal time-point and sequence of applying available treatments. Critically, without reliable methods that enable sequential monitoring of evolving genotypes in individual patients, we will never reach effective personalised driven treatment approaches. This review focuses on the clinical implications of prostate cancer genomics and the potential of cfDNA in facilitating treatment management

Cepheid Mass-loss and the Pulsation -- Evolutionary Mass Discrepancy

I investigate the discrepancy between the evolution and pulsation masses for Cepheid variables. A number of recent works have proposed that non-canonical mass-loss can account for the mass discrepancy. This mass-loss would be such that a 5Mo star loses approximately 20% of its mass by arriving at the Cepheid instability strip; a 14Mo star, none. Such findings would pose a serious challenge to our understanding of mass-loss. I revisit these results in light of the Padova stellar evolutionary models and find evolutionary masses are ($17\pm5$)% greater than pulsation masses for Cepheids between 5<M/Mo<14. I find that mild internal mixing in the main-sequence progenitor of the Cepheid are able to account for this mass discrepancy.Comment: 15 pages, 3 figures, ApJ accepte

Particle breakage criteria in discrete-element modelling

Previous work by the authors, using the discrete element method (DEM) has used the octahedral shear stress within a sphere together with a Weibull distribution of strengths and a size effect on average strength, to determine whether fracture occurs or not. This leads to fractal particle size distributions and a normal compression line which are consistent with experimental data. However there is no agreement in the literature as to what the fracture criterion should be and as yet it is not clear whether other criteria could lead to the correct evolution of voids ratio and particle size distribution under increasing stress. Various possibilities for the criterion have been studied in detail here to ascertain whether these other criteria may give the correct behaviour under normal compression. The use of the major principal stress within a particle, the mean stress, and the stress calculated from the maximum contact force on a particle are each investigated as alternatives to the octahedral shear stress. Only the criterion based on the maximum contact force is shown to give behaviour observed experimentally and the simulations shed further insight into the micro mechanics of normal compression

Validation of the log e–log σ normal compression law using particle strength data

This note is a study of experimental data on particle strength and normal compression, to establish whether the recently proposed normal compression law by McDowell and de Bono (2013) is supported and confirmed. A number of different sands are examined and found to support the hypothesis. In addition, some new simulations on sand mixtures are used to explain experimental results for quartz-feldspar mixtures. It would appear that the proposed compression law is also supported by the data for the sand mixtures

Spotting the diffusion of New Psychoactive Substances over the Internet

Online availability and diffusion of New Psychoactive Substances (NPS) represent an emerging threat to healthcare systems. In this work, we analyse drugs forums, online shops, and Twitter. By mining the data from these sources, it is possible to understand the dynamics of drugs diffusion and their endorsement, as well as timely detecting new substances. We propose a set of visual analytics tools to support analysts in tackling NPS spreading and provide a better insight about drugs market and analysis

Constraints on the Formation of the Globular Cluster IC 4499 from Multi-Wavelength Photometry

We present new multiband photometry for the Galactic globular cluster IC 4499 extending well past the main sequence turn-off in the U, B, V, R, I, and DDO51 bands. This photometry is used to determine that IC4499 has an age of 12 pm 1 Gyr and a cluster reddening of E(B-V) = 0.22 pm 0.02. Hence, IC 4499 is coeval with the majority of Galactic GCs, in contrast to suggestions of a younger age. The density profile of the cluster is observed to not flatten out to at least r~800 arcsec, implying that either the tidal radius of this cluster is larger than previously estimated, or that IC 4499 is surrounded by a halo. Unlike the situation in some other, more massive, globular clusters, no anomalous color spreads in the UV are detected among the red giant branch stars. The small uncertainties in our photometry should allow the detection of such signatures apparently associated with variations of light elements within the cluster, suggesting that IC 4499 consists of a single stellar population.Comment: accepted to MNRA

On the metallicity gradient of the Galactic disk

Aims: The iron abundance gradient in the Galactic stellar disk provides fundamental constraints on the chemical evolution of this important Galaxy component. However the spread around the mean slope is, at fixed Galactocentric distance, larger than estimated uncertainties. Methods: To provide quantitative constraints on these trends we adopted iron abundances for 265 classical Cepheids (more than 50% of the currently known sample) based either on high-resolution spectra or on photometric metallicity indices. Homogeneous distances were estimated using near-infrared Period-Luminosity relations. The sample covers the four disk quadrants and their Galactocentric distances range from ~5 to ~17 kpc. Results: A linear regression over the entire sample provides an iron gradient of -0.051+/-0.004 dex/kpc. The above slope agrees quite well, within the errors, with previous estimates based either on Cepheids or on open clusters covering similar Galactocentric distances. However, once we split the sample in inner (Rg < 8 kpc) and outer disk Cepheids we found that the slope (-0.130+/-0.015 dex/kpc) in the former region is ~3 times steeper than the slope in the latter one (-0.042+/-0.004 dex/kpc). We found that in the outer disk the radial distribution of metal-poor (MP, [Fe/H]<-0.02 dex) and metal-rich (MR) Cepheids across the four disk quadrants does not show a clear trend when moving from the innermost to the external disk regions. We also found that the relative fractions of MP and MR Cepheids in the 1st and in the 3rd quadrant differ at 8 sigma (MP) and 15 sigma (MR) level.Comment: 6 pages, 6 figures, A&A accepte