9,369 research outputs found
Offenders' Crime Narratives across Different Types of Crimes
The current study explores the roles offenders see themselves playing during an offence and their relationship to different crime types. One hundred and twenty incarcerated offenders indicated the narrative roles they acted out whilst committing a specific crime they remembered well. The data were subjected to Smallest Space Analysis (SSA) and four
themes were identified: Hero, Professional, Revenger and Victim in line with the recent theoretical framework posited for Narrative Offence Roles (Youngs & Canter, 2012). Further analysis showed that different subsets of crimes were more like to be associated with different narrative offence roles. Hero and Professional were found to be associated with property offences (theft, burglary and shoplifting), drug offences and robbery and Revenger
and Victim were found to be associated with violence, sexual offences and murder. The theoretical implications for understanding crime on the basis of offenders' narrative roles as well as practical implications are discussed
Statistical mixing and aggregation in Feller diffusion
We consider Feller mean-reverting square-root diffusion, which has been
applied to model a wide variety of processes with linearly state-dependent
diffusion, such as stochastic volatility and interest rates in finance, and
neuronal and populations dynamics in natural sciences. We focus on the
statistical mixing (or superstatistical) process in which the parameter related
to the mean value can fluctuate - a plausible mechanism for the emergence of
heavy-tailed distributions. We obtain analytical results for the associated
probability density function (both stationary and time dependent), its
correlation structure and aggregation properties. Our results are applied to
explain the statistics of stock traded volume at different aggregation scales.Comment: 16 pages, 3 figures. To be published in Journal of Statistical
Mechanics: Theory and Experimen
Can biological quantum networks solve NP-hard problems?
There is a widespread view that the human brain is so complex that it cannot
be efficiently simulated by universal Turing machines. During the last decades
the question has therefore been raised whether we need to consider quantum
effects to explain the imagined cognitive power of a conscious mind.
This paper presents a personal view of several fields of philosophy and
computational neurobiology in an attempt to suggest a realistic picture of how
the brain might work as a basis for perception, consciousness and cognition.
The purpose is to be able to identify and evaluate instances where quantum
effects might play a significant role in cognitive processes.
Not surprisingly, the conclusion is that quantum-enhanced cognition and
intelligence are very unlikely to be found in biological brains. Quantum
effects may certainly influence the functionality of various components and
signalling pathways at the molecular level in the brain network, like ion
ports, synapses, sensors, and enzymes. This might evidently influence the
functionality of some nodes and perhaps even the overall intelligence of the
brain network, but hardly give it any dramatically enhanced functionality. So,
the conclusion is that biological quantum networks can only approximately solve
small instances of NP-hard problems.
On the other hand, artificial intelligence and machine learning implemented
in complex dynamical systems based on genuine quantum networks can certainly be
expected to show enhanced performance and quantum advantage compared with
classical networks. Nevertheless, even quantum networks can only be expected to
efficiently solve NP-hard problems approximately. In the end it is a question
of precision - Nature is approximate.Comment: 38 page
PESSTO monitoring of SN 2012hn: further heterogeneity among faint type I supernovae
We present optical and infrared monitoring data of SN 2012hn collected by the
Public ESO Spectroscopic Survey for Transient Objects (PESSTO). We show that SN
2012hn has a faint peak magnitude (MR ~ -15.7) and shows no hydrogen and no
clear evidence for helium in its spectral evolution. Instead, we detect
prominent Ca II lines at all epochs, which relates this transient to previously
described 'Ca-rich' or 'gap' transients. However, the photospheric spectra
(from -3 to +32 d with respect to peak) of SN 2012hn show a series of
absorption lines which are unique, and a red continuum that is likely intrinsic
rather than due to extinction. Lines of Ti II and Cr II are visible. This may
be a temperature effect, which could also explain the red photospheric colour.
A nebular spectrum at +150d shows prominent CaII, OI, CI and possibly MgI lines
which appear similar in strength to those displayed by core-collapse SNe. To
add to the puzzle, SN 2012hn is located at a projected distance of 6 kpc from
an E/S0 host and is not close to any obvious starforming region. Overall SN
2012hn resembles a group of faint H-poor SNe that have been discovered recently
and for which a convincing and consistent physical explanation is still
missing. They all appear to explode preferentially in remote locations offset
from a massive host galaxy with deep limits on any dwarf host galaxies,
favouring old progenitor systems. SN 2012hn adds heterogeneity to this sample
of objects. We discuss potential explosion channels including He-shell
detonations and double detonations of white dwarfs as well as peculiar
core-collapse SNe.Comment: 14 pages, 14 figures, accepted to MNRAS on 14/10/201
The progenitor and early evolution of the Type IIb SN 2016gkg
We report initial observations and analysis on the Type IIb SN~2016gkg in the
nearby galaxy NGC~613. SN~2016gkg exhibited a clear double-peaked light curve
during its early evolution, as evidenced by our intensive photometric follow-up
campaign. SN~2016gkg shows strong similarities with other Type IIb SNe, in
particular with respect to the \he~emission features observed in both the
optical and near infrared. SN~2016gkg evolved faster than the prototypical
Type~IIb SN~1993J, with a decline similar to that of SN~2011dh after the first
peak. The analysis of archival {\it Hubble Space Telescope} images indicate a
pre-explosion source at SN~2016gkg's position, suggesting a progenitor star
with a mid F spectral type and initial mass \msun, depending on
the distance modulus adopted for NGC~613. Modeling the temperature evolution
within of explosion, we obtain a progenitor radius of
\rsun, smaller than that obtained from the analysis of the
pre-explosion images (\rsun).Comment: 7 pages, 5 figures. Submitted to ApJ Letter
Back Pay in Employment Discrimination Cases
This Special Project examines the back pay decisions and analyzes the problems that have confronted the courts dealing with this remedy for employment discrimination in the context of Title VII and section 1981. Because of the enormity of the issues that have arisen in Stage I of the proceedings, however, and the extensive coverage given those problems by the courts and commentators, the Special Project will deal only with the recovery stage, or Stage II, of the litigation. Consequently, the reader should assume that liability for employment discrimination has already been established in each of the cases discussed below. Before reaching the various procedural and substantive issues surrounding back pay awards, however, the Project, in part II, presents an over-view of the statutory authority for back pay including the legislative history of Title VII and section 1981. Part II also discusses the development of the appropriate standard for the exercise of judicial discretion in awarding back pay. Part III examines the parties liable for the payment of back pay. In part IV the Project explores presumptive eligibility for back pay and in part V considers possible grounds on which a defendant may seek to rebut the presumption. Parts VI and VII discuss the proof-of-claim procedure that must be followed by discriminatees claiming back pay and the procedure for determining individual awards. Part VIII then identifies and analyzes the various problems facing courts in allocating the burdens of proof that plaintiffs and defendants must meet before the court can determine individual awards. Following the discussion of the order and allocation of the burdens of proof, part IX outlines the various methods used by the courts to compute individual back pay awards and also discusses other issues such as the elements includable and deductible, the mitigation requirement,and the limitation periods for back pay. In part X the Special Project examines the problems that may arise when the parties agree to a settlement of back pay claims
Light curves of hydrogen-poor Superluminous Supernovae from the Palomar Transient Factory
We investigate the light-curve properties of a sample of 26 spectroscopically
confirmed hydrogen-poor superluminous supernovae (SLSNe-I) in the Palomar
Transient Factory (PTF) survey. These events are brighter than SNe Ib/c and SNe
Ic-BL, on average, by about 4 and 2~mag, respectively. The peak absolute
magnitudes of SLSNe-I in rest-frame band span ~mag, and these peaks are not powered by radioactive Ni,
unless strong asymmetries are at play. The rise timescales are longer for SLSNe
than for normal SNe Ib/c, by roughly 10 days, for events with similar decay
times. Thus, SLSNe-I can be considered as a separate population based on
photometric properties. After peak, SLSNe-I decay with a wide range of slopes,
with no obvious gap between rapidly declining and slowly declining events. The
latter events show more irregularities (bumps) in the light curves at all
times. At late times, the SLSN-I light curves slow down and cluster around the
Co radioactive decay rate. Powering the late-time light curves with
radioactive decay would require between 1 and 10 of Ni masses.
Alternatively, a simple magnetar model can reasonably fit the majority of
SLSNe-I light curves, with four exceptions, and can mimic the radioactive decay
of Co, up to days from explosion. The resulting spin values do
not correlate with the host-galaxy metallicities. Finally, the analysis of our
sample cannot strengthen the case for using SLSNe-I for cosmology.Comment: 120 pages, 48 figures, 78 tables. ApJ in pres
SNe 2013K and 2013am: observed and physical properties of two slow, normal Type IIP events
We present one year of optical and near-infrared photometry and spectroscopy
of the Type IIP SNe 2013K and 2013am. Both objects are affected by significant
extinction, due to their location in dusty regions of their respective host
galaxies, ESO 009-10 and NGC 3623 (M65). From the photospheric to nebular
phases, these objects display spectra congruent with those of underluminous
Type IIP SNe (i.e. the archetypal SNe 1997D or 2005cs), showing low
photospheric velocities (~2 X 10**3 km/s at 50d) together with features arising
from Ba II which are particularly prominent in faint SNe IIP. The peak V-band
magnitudes of SN 2013K (-15.6 mag) and SN 2013am (-16.2 mag) are fainter than
standard-luminosity Type IIP SNe. The ejected Nickel masses are 0.012+-0.010
and 0.015+-0.006 Msol for SN 2013K and SN 2013am, respectively. The physical
properties of the progenitors at the time of explosion are derived through
hydrodynamical modelling. Fitting the bolometric curves, the expansion velocity
and the temperature evolution, we infer total ejected masses of 12 and 11.5
Msol, pre-SN radii of ~460 and ~360 Rsol, and explosion energies of 0.34 foe
and 0.40 foe for SN 2013K and SN 2013am. Late time spectra are used to estimate
the progenitor masses from the strength of nebular emission lines, which turn
out to be consistent with red supergiant progenitors of ~15 Msol. For both SNe,
a low-energy explosion of a moderate-mass red supergiant star is therefore the
favoured scenario.Comment: accepted for publication MNRA
Fractional urinary fluoride excretion of 6-7-year-old children attending schools in low-fluoride and naturally fluoridated areas in the UK
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