124 research outputs found
Recommended from our members
Deep Learning for Single-Molecule Science
Exploring and making predictions based on single-molecule data can be challenging, not only due to the sheer size of the datasets, but also because a priori knowledge about the signal characteristics is typically limited and poor signal-to-noise ratio. For example, hypothesis-driven data exploration, informed by an expectation of the signal characteristics, can lead to interpretation bias or loss of information. Equally, even when the different data categories are known, e.g., the four bases in DNA sequencing, it is often difficult to know how to make best use of the available information content. The latest developments in Machine Learning (ML), so-called Deep Learning (DL) offers an interesting, new avenues to address such challenges. In some applications, such as speech and image recognition, DL has been able to outperform conventional Machine Learning strategies and even human performance. However, to date DL has not been applied much in single-molecule science, presumably in part because relatively little is known about the 'internal workings' of such DL tools within single-molecule science as a field. In this Tutorial, we make an attempt to illustrate in a step-by-step guide how one of those, a Convolutional Neural Network, may be used for base calling in DNA sequencing applications. We compare it with a Support Vector Machine as a more conventional ML method, and and discuss some of the strengths and weaknesses of the approach. In particular, a 'deep' neural network has many features of a 'black box', which has important implications on how we look at and interpret data
LSST Science Book, Version 2.0
A survey that can cover the sky in optical bands over wide fields to faint
magnitudes with a fast cadence will enable many of the exciting science
opportunities of the next decade. The Large Synoptic Survey Telescope (LSST)
will have an effective aperture of 6.7 meters and an imaging camera with field
of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over
20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with
fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a
total point-source depth of r~27.5. The LSST Science Book describes the basic
parameters of the LSST hardware, software, and observing plans. The book
discusses educational and outreach opportunities, then goes on to describe a
broad range of science that LSST will revolutionize: mapping the inner and
outer Solar System, stellar populations in the Milky Way and nearby galaxies,
the structure of the Milky Way disk and halo and other objects in the Local
Volume, transient and variable objects both at low and high redshift, and the
properties of normal and active galaxies at low and high redshift. It then
turns to far-field cosmological topics, exploring properties of supernovae to
z~1, strong and weak lensing, the large-scale distribution of galaxies and
baryon oscillations, and how these different probes may be combined to
constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at
http://www.lsst.org/lsst/sciboo
Rapid Eye Movements in Sleep Furnish a Unique Probe Into Consciousness
The neural correlates of rapid eye movements (REMs) in sleep are extraordinarily robust;
including REM-locked multisensory-motor integration and accompanying activation
in the retrosplenial cortex, the supplementary eye field and areas encompassing
cholinergic basal nucleus (Hong et al., 2009). The phenomenology of REMs speaks
to the notion that perceptual experience in both sleep and wakefulness is a constructive
process – in which we generate predictions of sensory inputs and then test those
predictions through actively sampling the sensorium with eye movements. On this view,
REMs during sleep may index an internalized active sampling or ‘scanning’ of selfgenerated
visual constructs that are released from the constraints of visual input. If this
view is correct, it renders REMs an ideal probe to study consciousness as “an exclusively
internal affair” (Metzinger, 2009). In other words, REMs offer a probe of active inference –
in the sense of predictive coding – when the brain is isolated from the sensorium
in virtue of the natural blockade of sensory afferents during REM sleep. Crucially,
REMs are temporally precise events that enable powerful inferences based on time
series analyses. As a natural, task-free probe, (REMs) could be used in non-compliant
subjects, including infants and animals. In short, REMs constitute a promising probe
to study the ontogenetic and phylogenetic development of consciousness and perhaps
the psychopathology of schizophrenia and autism, which have been considered in terms
of aberrant predictive coding
Fraud, banking crisis, and regulatory enforcement: Evidence from micro-level transactions data
Banking crises, Regulatory enforcement, Related lending, Looting, Turkey,
- …