3,006 research outputs found
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
()% 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
Muon Spin Relaxation Studies of Superconductivity in a Crystalline Array of Weakly Coupled Metal Nanoparticles
We report Muon Spin Relaxation studies in weak transverse fields of the
superconductivity in the metal cluster compound,
Ga[N(SiMe)]-LiBr(thf)2toluene. The temperature and field dependence of the muon spin relaxation
rate and Knight shift clearly evidence type II bulk superconductivity below
K, with T,
T, and weak flux pinning. The data
are well described by the s-wave BCS model with weak electron-phonon coupling
in the clean limit. A qualitative explanation for the conduction mechanism in
this novel type of narrow band superconductor is presented.Comment: 4 figures, 5 page
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
Superconductivity in a Molecular Metal Cluster Compound
Compelling evidence for band-type conductivity and even bulk
superconductivity below K has been found in
Ga-NMR experiments in crystalline ordered, giant Ga
cluster-compounds. This material appears to represent the first realization of
a theoretical model proposed by Friedel in 1992 for superconductivity in
ordered arrays of weakly coupled, identical metal nanoparticles.Comment: 5 pages, 4 figure
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
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
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
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