3,769 research outputs found
The Effectiveness of State and Local Regulation of Handguns: A Statistical Analysis
One aspect of the continuing debate over weapons control, apart from Constitutional issues, is whether legislation is inherently capable of reducing crime and deaths by shooting. The opponents of increased control, tacitly admitting that empirical evidence is one means for measuring the effect of weapons regulation, have contended that [e]xpert opinion and compelling evidence seem to indicate that the amount or kind of crime in a community is not substantially affected by the relative ease with which a person can obtain a firearm. National Rifle Association of America, The Gun Law Problem 10. In the following study the authors employ data analysis techniques to examine the efficacy of state and municipal controls on handguns. They conclude that many lives would be saved if all states increased their level of control to that of New Jersey, the state having the most stringent gun control laws
The Effectiveness of State and Local Regulation of Handguns: A Statistical Analysis
One aspect of the continuing debate over weapons control, apart from Constitutional issues, is whether legislation is inherently capable of reducing crime and deaths by shooting. The opponents of increased control, tacitly admitting that empirical evidence is one means for measuring the effect of weapons regulation, have contended that [e]xpert opinion and compelling evidence seem to indicate that the amount or kind of crime in a community is not substantially affected by the relative ease with which a person can obtain a firearm. National Rifle Association of America, The Gun Law Problem 10. In the following study the authors employ data analysis techniques to examine the efficacy of state and municipal controls on handguns. They conclude that many lives would be saved if all states increased their level of control to that of New Jersey, the state having the most stringent gun control laws
Cross-sectional study assessing HIV related knowledge, attitudes and behavior in Namibian public sector employees in capital and regional settings
The study objective was to assess the current status of HIV knowledge, attitudes and behavior (KAB) among employees of Namibian ministries. As most HIV campaigning takes place in the capital of Windhoek, an additional aim was to compare Windhoek to four regions (Hardap, Erongo, Oshana, and Caprivi). Between January and March 2011 a cross-sectional survey was conducted in two Namibian ministries, with participants selected randomly from the workforce. Data collection was based on questionnaires. 832 participants were included in the study (51.6% male). Nearly 90% of participants reported to have been tested for HIV before. Knowledge about HIV transmission ranged from 67% to 95% of correct answers, with few differences between the capital and regions. However, a knowledge gap regarding HIV transmission and prevention was seen. In particular, we found significantly lower knowledge regarding transmission from mother-to-child during pregnancy and higher rate of belief in a supernatural role in HIV transmission. In addition, despite many years of HIV prevention activities, a substantial proportion of employees had well-known HIV risk factors including multiple concurrent partnership rates (21%), intergenerational sex (19%), and lower testing rates for men (82% compared to women with 91%)
Species–area relationships always overestimate extinction rates from habitat loss : comment
Author Posting. © Ecological Society of America, 2013. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecology 94 (2013): 761–763, doi:10.1890/12-0047.1.The species–area relationship summarizes the relationship
between the average number of species in a
region and its area. This relationship provides a basis for
predicting the loss of species associated with loss of
habitat (e.g., Pimm and Raven 2000). The approach
involves two steps. First, as discussed in more detail
below, the species–area relationship is used to predict the
number of species that are endemic to the habitat at risk
based on its area. Second, these endemic species are
assumed to become extinct should this habitat be lost. In
a controversial paper, He and Hubbell (2011) argued
that the way in which the species–area relationship is
used to predict the number of endemic species is incorrect
when individual organisms are aggregated in space and
argued that this explains a discrepancy between predicted
and observed extinction rates associated with habitat
loss. The controversy surrounding the paper focused
primarily on the second part of their argument (Brooks
2011, Evans et al. 2011, He and Hubbell 2012, Pereira et
al. 2012, Thomas and Williamson 2012). Here, we focus
on the details underlying the first part.U. Roll is
supported by the Adams Fellowship Program of the Israel
Academy of Sciences and Humanities. L. Stone is supported by
the Israeli Science Foundation
Surveying the Inner Halo of the Galaxy with 2MASS-Selected Horizontal Branch Candidates
We use 2MASS photometry to select blue horizontal branch (BHB) candidates
covering the sky |b|>15 deg. A 12.5<J<15.5 sample of BHB stars traces the thick
disk and inner halo to d<9 kpc, with a density comparable to that of M giant
stars. We base our sample selection strategy on the Century Survey Galactic
Halo Project, a survey that provides a complete, spectroscopically-identified
sample of blue stars to a similar depth as the 2MASS catalog. We show that a
-0.20<(J-H)_0<0.10, -0.10<(H-K)_0<0.10 color-selected sample of stars is 65%
complete for BHB stars, and is composed of 47% BHB stars. We apply this
photometric selection to the full 2MASS catalog, and see no spatial
overdensities of BHB candidates at high Galactic latitude |b|>50 deg. We insert
simulated star streams into the data and conclude that the high Galactic
latitude BHB candidates are consistent with having no ~5 deg wide star stream
with density greater than 0.33 objects deg^-2 at the 95% confidence level. The
absence of structure suggests there have been no major accretion events in the
inner halo in the last few Gyr. However, at low Galactic latitudes a two-point
angular correlation analysis reveals structure on angular scales <1 deg. This
structure is apparently associated with stars in the thick disk, and has a
physical scale of 10-100 pc. Interestingly, such structures are expected by
cosmological simulations that predict the majority of the thick disk may arise
from accretion and disruption of satellite mergers.Comment: 11 pages, including figures. Accepted by AJ with minor revision
Government Misconduct and Convicting the Innocent: The Role of Prosecutors, Police and Other Law Enforcement
This is a report about the role of official misconduct in the conviction of innocent people. We discuss cases that are listed in the National Registry of Exonerations, an ongoing online archive that includes all known exonerations in the United States since 1989, 2,663 as of this writing. This Report describes official misconduct in the first 2,400 exonerations in the Registry, those posted by February 27, 2019.
In general, we classify a case as an “exoneration” if a person who was convicted of a crime is officially and completely cleared based on new evidence of innocence.
The Report is limited to misconduct by government officials that contributed to the false convictions of defendants who were later exonerated—misconduct that distorts the evidence used to determine guilt or innocence. Concretely, that means misconduct that produces unreliable, misleading or false evidence of guilt, or that conceals, distorts or undercuts true evidence of innocence
Temperature dependence of the energy dissipation in dynamic force microscopy
The dissipation of energy in dynamic force microscopy is usually described in
terms of an adhesion hysteresis mechanism. This mechanism should become less
efficient with increasing temperature. To verify this prediction we have
measured topography and dissipation data with dynamic force microscopy in the
temperature range from 100 K up to 300 K. We used
3,4,9,10-perylenetetracarboxylic-dianhydride (PTCDA) grown on KBr(001), both
materials exhibiting a strong dissipation signal at large frequency shifts. At
room temperature, the energy dissipated into the sample (or tip) is 1.9
eV/cycle for PTCDA and 2.7 eV/cycle for KBr, respectively, and is in good
agreement with an adhesion hysteresis mechanism. The energy dissipation over
the PTCDA surface decreases with increasing temperature yielding a negative
temperature coefficient. For the KBr substrate, we find the opposite behaviour:
an increase of dissipated energy with increasing temperature. While the
negative temperature coefficient in case of PTCDA agrees rather well with the
adhesion hysteresis model, the positive slope found for KBr points to a
hitherto unknown dissipation mechanism
Refund to Savings 2015-2016: Field Experiments to Promote Tax-Time Saving in Low- and Moderate-Income Households
This report covers the design and impacts of the R2S experiments in the 2015 and 2016 tax seasons (which include the 2014 and 2015 tax years), and also includes results from a 6-month follow-up survey conducted in 2015 to assess how the impacts of R2S interventions persist over time. These interventions reached a large number of tax filers in both of these years; 646,116 in 2015 and 284,125 in 2016
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Beagle 2: Mission to Mars — current status
Beagle 2, developed in the UK, was launched on June 2, 2003. It landed on Mars on December 25th, 2003 in Isidis Planitia, a large sedimentary basin. To date, the team is awaiting signals from the Beagle 2 lander. Current status of the mission will be reported
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