241 research outputs found
Conducta antisocial adolescente bajo un enfoque integrador de tres teorías criminológicas
In order to test the theories of Differential Association, Social Control and General Crime, the
relationship between antisocial behavior and key constructs of the theories was analyzed, namely, “favourable definitions” (differential association), “attachment” (social control) and “self-control”. The propositional integrated side-by-side approach of Tibbets and Hemmens (2010) was used to determine the weight
of said constructs in the prediction of antisocial behavior with a binary logistic regression model entering the
explanatory variables in blocks. Sociodemographic variables such as sex and the size of the city were included. A total of 2,395 adolescents were surveyed in schools located in three cities (large, medium and small) in Venezuela. The results show that, of the three variables derived from differential association theory, the favourable
definitions of friends towards participation in criminal acts served as predictors of antisocial behavior at
the individual level. Of the ten variables derived from social control theory, attachment to school and participation in
activities without family supervision predict antisocial behaviour. Self-control (from the general theory of crime) also predicts antisocial behavior
Autocontrol y conducta desviada: Una exploración con datos Venezolanos. (Self control and deviant behaviour: An exploration with Venezuelan data)
Gottfredson and Hirschi’s self-control theory is tested with
adolescent Venezuelan students (n = 2354), examining the relationship between deviant behavior, self-control, age, sex, socioeconomic status, and size of settlement. The hypothesis that “low self-control increases the probability of individual and group deviance” is supported, except for drug-related behaviors. Males with low self-control show a greater probability of engaging in individual and group deviant behaviors
Reconstruction of the pose of uncalibrated cameras via user-generated videos
Extraction of 3D geometry from hand-held unsteady uncalibrated cameras faces multiple difficulties: finding usable frames, feature-matching and unknown variable focal length to name three. We have built a prototype system to allow a user to spatially navigate playback viewpoints of an event of interest, using geometry automatically recovered from casually captured videos. The system, whose workings we present in this paper, necessarily estimates not only scene geometry, but also relative viewpoint position, overcoming the mentioned difficulties in the process. The only inputs required are video sequences from various viewpoints of a common scene, as are readily available online from sporting and music events. Our methods make no assumption of the synchronization of the input and do not require file metadata, instead exploiting the video to self-calibrate. The footage need only contain some camera rotation with little translation—for hand-held event footage a likely occurrence.This is the author accepted manuscript. The final version is available from IEEE via http://dx.doi.org/10.1145/2659021.265902
The Scottish Nephrops Survey Phase I: The Factors During Capture, Post-Capture Handling, Delivery and Factory Processing of Nephrops Tails that Affect Product Freshness and Quality
The Scottish Nephrops Survey Phase II: The Processes that Underlie Quality Loss in the Whole Animal Compared to the Tailed Product
Imaging resonant dissipation from individual atomic defects in graphene
Conversion of electric current into heat involves microscopic processes that
operate on nanometer length-scales and release minute amounts of power. While
central to our understanding of the electrical properties of materials,
individual mediators of energy dissipation have so far eluded direct
observation. Using scanning nano-thermometry with sub-micro K sensitivity we
visualize and control phonon emission from individual atomic defects in
graphene. The inferred electron-phonon 'cooling power spectrum' exhibits sharp
peaks when the Fermi level comes into resonance with electronic quasi-bound
states at such defects, a hitherto uncharted process. Rare in the bulk but
abundant at graphene's edges, switchable atomic-scale phonon emitters define
the dominant dissipation mechanism. Our work offers new insights for addressing
key materials challenges in modern electronics and engineering dissipation at
the nanoscale
A universally applicable method of operon map prediction on minimally annotated genomes using conserved genomic context.
An important step in understanding the regulation of a prokaryotic genome is the generation of its transcription unit map. The current strongest operon predictor depends on the distributions of intergenic distances (IGD) separating adjacent genes within and between operons. Unfortunately, experimental data on these distance distributions are limited to Escherichia coli and Bacillus subtilis. We suggest a new graph algorithmic approach based on comparative genomics to identify clusters of conserved genes independent of IGD and conservation of gene order. As a consequence, distance distributions of operon pairs for any arbitrary prokaryotic genome can be inferred. For E.coli, the algorithm predicts 854 conserved adjacent pairs with a precision of 85%. The IGD distribution for these pairs is virtually identical to the E.coli operon pair distribution. Statistical analysis of the predicted pair IGD distribution allows estimation of a genome-specific operon IGD cut-off, obviating the requirement for a training set in IGD-based operon prediction. We apply the method to a representative set of eight genomes, and show that these genome-specific IGD distributions differ considerably from each other and from the distribution in E.coli
Extensions of vector bundles on the Fargues-Fontaine curve
We completely classify the possible extensions between semistable vector bundles on the Fargues-Fontaine curve (over an algebraically closed perfectoid field), in terms of a simple condition on Harder-Narasimhan polygons. Our arguments rely on a careful study of various moduli spaces of bundle maps, which we define and analyze using Scholze's language of diamonds. This analysis reduces our main results to a somewhat involved combinatorial problem, which we then solve via a reinterpretation in terms of the euclidean geometry of Harder-Narasimhan polygons
Micromagnetometry of two-dimensional ferromagnets
The study of atomically thin ferromagnetic crystals has led to the discovery
of unusual magnetic behaviour and provided insight into the magnetic properties
of bulk materials. However, the experimental techniques that have been used to
explore ferromagnetism in such materials cannot probe the magnetic field
directly. Here, we show that ballistic Hall micromagnetometry can be used to
measure the magnetization of individual two-dimensional ferromagnets. Our
devices are made by van der Waals assembly in such a way that the investigated
ferromagnetic crystal is placed on top of a multi-terminal Hall bar made from
encapsulated graphene. We use the micromagnetometry technique to study
atomically thin chromium tribromide (CrBr3). We find that the material remains
ferromagnetic down to monolayer thickness and exhibits strong out-of-plane
anisotropy. We also find that the magnetic response of CrBr3 varies little with
the number of layers and its temperature dependence cannot be described by the
simple Ising model of two-dimensional ferromagnetism.Comment: 19 pages, 12 figure
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