Overview on new psychoactive substances in Portugal

This working paper provides an overview of the phenomenon of new psychoactive substances (NPS) in Portugal, including suggested definitions of NPS, a review of drug policy in Portugal, NPS markets, NPS demand and supply, prevention strategies and insights from expert interviews. NPS emerged in Portugal in 2007, and despite the closure of NPS physical selling points in 2013 and decreasing rates of NPS consumption, the market seems to be continuing with new particularities: a rise in unintentional consumers and the increasing association with problematic drug use. The new trends in users and consumption patterns as well as new forms of communication, acquisition, and production of substances have challenged conventional mechanisms of drug control in Portugal

Beyond Correlation Filters: Learning Continuous Convolution Operators for Visual Tracking

Discriminative Correlation Filters (DCF) have demonstrated excellent performance for visual object tracking. The key to their success is the ability to efficiently exploit available negative data by including all shifted versions of a training sample. However, the underlying DCF formulation is restricted to single-resolution feature maps, significantly limiting its potential. In this paper, we go beyond the conventional DCF framework and introduce a novel formulation for training continuous convolution filters. We employ an implicit interpolation model to pose the learning problem in the continuous spatial domain. Our proposed formulation enables efficient integration of multi-resolution deep feature maps, leading to superior results on three object tracking benchmarks: OTB-2015 (+5.1% in mean OP), Temple-Color (+4.6% in mean OP), and VOT2015 (20% relative reduction in failure rate). Additionally, our approach is capable of sub-pixel localization, crucial for the task of accurate feature point tracking. We also demonstrate the effectiveness of our learning formulation in extensive feature point tracking experiments. Code and supplementary material are available at http://www.cvl.isy.liu.se/research/objrec/visualtracking/conttrack/index.html.Comment: Accepted at ECCV 201

Galaxy formation in the Planck cosmology - II. Star-formation histories and post-processing magnitude reconstruction

We adapt the L-Galaxies semi-analytic model to follow the star-formation histories (SFH) of galaxies -- by which we mean a record of the formation time and metallicities of the stars that are present in each galaxy at a given time. We use these to construct stellar spectra in post-processing, which offers large efficiency savings and allows user-defined spectral bands and dust models to be applied to data stored in the Millennium data repository. We contrast model SFHs from the Millennium Simulation with observed ones from the VESPA algorithm as applied to the SDSS-7 catalogue. The overall agreement is good, with both simulated and SDSS galaxies showing a steeper SFH with increased stellar mass. The SFHs of blue and red galaxies, however, show poor agreement between data and simulations, which may indicate that the termination of star formation is too abrupt in the models. The mean star-formation rate (SFR) of model galaxies is well-defined and is accurately modelled by a double power law at all redshifts: SFR proportional to $1/(x^{-1.39}+x^{1.33})$, where $x=(t_a-t)/3.0\,$Gyr, $t$ is the age of the stars and $t_a$ is the loopback time to the onset of galaxy formation; above a redshift of unity, this is well approximated by a gamma function: SFR proportional to $x^{1.5}e^{-x}$, where $x=(t_a-t)/2.0\,$Gyr. Individual galaxies, however, show a wide dispersion about this mean. When split by mass, the SFR peaks earlier for high-mass galaxies than for lower-mass ones, and we interpret this downsizing as a mass-dependence in the evolution of the quenched fraction: the SFHs of star-forming galaxies show only a weak mass dependence.Comment: Accepted version of the paper, to appear in MNRAS. Compared to the original version, contains more detail on the post-processing of magnitudes, including a table of rms magnitude errors. SFHs available on Millennium database http://gavo.mpa-garching.mpg.de/MyMillennium

Street space allocation – new tools and methods, with a Lisbon application [Full paper]

The allocation of space to different uses in busy city streets is a complex and conten-tious process. Decisions to reallocate streetspace are usually based on public consulta-tion and modelling of a few street redesign options, but results are not compared sys-tematically. In addition, the set of options considered is usually incomplete. This paper proposes a new process for streetspace reallocation, including option generation (with online and physical tools), estimation of performance indicators (with microsimula-tion), and comparison of options (with a new appraisal tool). The process was applied to the redesign of a busy street in Lisbon. Several options were generated, all involving reducing the space allocated to general motorised traffic. Microsimulation showed that allocating more space to some street uses also bring benefits to other uses. The option to allocate more space to both bus users and pedestrians does not deteriorate move-ment by other modes. However, appraisal showed that some redesign options go against technical/design standards or political priorities

Measurement of miniband parameters of a doped superlattice by photoluminescence in high magnetic fields

We have studied a 50/50\AA superlattice of GaAs/Al$_{0.21}$Ga$_{0.79}$As composition, modulation-doped with Si, to produce $n=1.4\times 10^{12}$ cm$^{-2}$ electrons per superlattice period. The modulation-doping was tailored to avoid the formation of Tamm states, and photoluminescence due to interband transitions from extended superlattice states was detected. By studying the effects of a quantizing magnetic field on the superlattice photoluminescence, the miniband energy width, the reduced effective mass of the electron-hole pair, and the band gap renormalization could be deduced.Comment: minor typing errors (minus sign in eq. (5)

NPS use in Portugal

Novas Substâncias Psicoativas (NSP) representam um grupo de substâncias que tem crescido rapidamente e cujos mercados têm beneficiado do desenvolvimento tecnológico. EMCDDA define-as como “substâncias naturais ou sintéticas que não são controladas pelos organismos oficiais e frequentemente visam mimetizar os efeitos das substâncias controladas”. Na metodologia usou-se um questionário aplicado presencialmente em contextos recreativos e online, em sítios e fóruns com temática relacionada com substâncias psicoativas. Aqui caracterizamos os consumidores portugueses de NSP quanto às substâncias, padrões de uso e contextos de consumo. Os resultados demonstram que os alucinogénicos, os estimulantes e os canabinoides são os tipos de NSP mais consumidos. Os principais contextos de consumo são os contextos recreativos, a própria casa ou a de amigos. Concluindo destacamse alguns aspetos relacionados com as particularidades destes consumos, especialmente no que se relaciona com o papel das tecnologias na relação com as substâncias, entre consumidores e com os mercados.info:eu-repo/semantics/publishedVersio

O mercado emergente das novas drogas: o novo desafio social e político

O presente artigo pretende dar continuidade e suporte à comunicação realizada no âmbito do Congresso Nacional de Adictologia. O fenómeno das Novas Substâncias Psicoativas (NSP) é uma problemática emergente e em constante evolução, que se traduz no aparecimento de novos compostos químicos ou de produtos naturais habitualmente não destinados ao consumo humano, com efeitos semelhantes aos das drogas ilícitas mais tradicionais, mas não controlados. Em Portugal, desde 2007 que nos deparamos com este novo desafio. Com mais ou menos destaque, o debate público e os factos políticos e institucionais associados ao tema foram acontecendo e sendo marcados por um conjunto considerável de ações, polémicas e discussões ao longo dos últimos tempos, sugerindo uma mudança significativa no paradigma das drogas e abrindo um novo leque de oportunidades no mercado de estupefacientes. As novas tendências de consumo, bem como as novas formas de comunicação, aquisição e produção de substâncias, acabam por definir e pôr à prova os mecanismos mais convencionais de ação e controlo de drogas, tornando-os insuficientes e pouco eficazes nos seus resultados. É neste contexto que surge um novo quadro legislativo que aqui apresentamos e discutimos, tendo em conta o seu enquadramento e implicações.info:eu-repo/semantics/publishedVersio

Superlattice Magnetophonon Resonances in Strongly Coupled InAs/GaSb Superlattices

We report an experimental study of miniband magnetoconduction in semiconducting InAs/GaSb superlattices. For samples with miniband widths below the longitudinal optical phonon energy we identify a new superlattice magnetophonon resonance (SLMPR) caused by resonant scattering of electrons across the mini-Brillouin zone. This new resonant feature arises directly from the drift velocity characteristics of the superlattice dispersion and total magnetic quantisation of the superlattice Landau level minibands.Comment: 9 pages, 8 figures, submitted to Phys. Rev.