797 research outputs found
Effectiveness of battlefield-ethics training during combat deployment: a programme assessment
Background Breakdowns in the ethical conduct of soldiers towards non-combatants on the battlefi eld are of grave concern in war. Evidence-based training approaches to prevent unethical conduct are scarce. We assessed the eff ectiveness of battlefi eld-ethics training and factors associated with unethical battlefi eld conduct.
Methods The training package, based on movie vignettes and leader-led discussions, was administered 7 to 8 months into a 15-month high-intensity combat deployment in Iraq, between Dec 11, 2007, and Jan 30, 2008. Soldiers from an infantry brigade combat team (total population about 3500) were randomly selected, on the basis of company and the last four digits of each soldier’s social security number, and invited to complete an anonymous survey 3 months after completion of the training. Reports of unethical behaviour and attitudes in this sample were compared with a randomly selected pre-training sample from the same brigade. The response patterns for ethical behaviour and reporting of ethical violations were analysed with chi-square analyses. We developed two logistic regression models using self-reported unethical behaviours as dependent variables. Factors associated with unethical conduct, including combat experiences and post-traumatic stress disorder (PTSD), were assessed with validated scales.
Findings Of 500 randomly selected soldiers 421 agreed to participate in the anonymous post-training survey. A total of 397 soldiers of the same brigade completed the pre-training survey. Training was associated with significantly lower rates of unethical conduct of soldiers and greater willingness to report and address misconduct than in those before training. For example, reports of unnecessary damage or destruction of private property decreased from 13·6% (54 of 397; 95% CI 10·2–17·0) before training to 5·0% (21 of 421; 2·9–7·1) after training (percent difference –63·2%; p\u3c0·0001), and willingness to report a unit member for mistreatment of a non-combatant increased from 36·0% (143 of 397; 31·3–40·7) to 58·9% (248 of 421; 54·2–63·6; percent difference 63·6; p\u3c0·0001). Nearly all participants (410 [97%]) reported that training made it clear how to respond towards non-combatants. Combat frequency and intensity was the strongest predictor of unethical behaviour; PTSD was not a significant predictor of unethical behaviour after controlling for combat experiences.
Interpretation Leader-led battlefield ethics training positively influenced soldiers’ understanding of how to interact with and treat non-combatants, and reduced reports of ethical misconduct. Unethical battlefield conduct was associated with high-intensity combat but not with PTSD
First Simultaneous Optical and EUV Observations of the Quasi-Coherent Oscillations of SS Cygni
Using EUV photometry obtained with the Extreme Ultraviolet Explorer (EUVE)
satellite and UBVR optical photometry obtained with the 2.7-m telescope at
McDonald Observatory, we have detected quasi-coherent oscillations (so-called
``dwarf nova oscillations'') in the EUV and optical flux of the dwarf nova SS
Cygni during its 1996 October outburst. There are two new results from these
observations. First, we have for the first time observed ``frequency
doubling:'' during the rising branch of the outburst, the period of the EUV
oscillation was observed to jump from 6.59 s to 2.91 s. Second, we have for the
first time observed quasi-coherent oscillations simultaneously in the optical
and EUV. We find that the period and phase of the oscillations are the same in
the two wavebands, finally confirming the long-held assumption that the periods
of the optical and EUV/soft X-ray oscillations of dwarf novae are equal. The
UBV oscillations can be simply the Rayleigh-Jeans tail of the EUV oscillations
if the boundary layer temperature kT_bb <~ 15 eV and hence the luminosity L_bb
>~ 1.2e34 (d/75 pc)^2 erg/s (comparable to that of the accretion disk).
Otherwise, the lack of a phase delay between the EUV and optical oscillations
requires that the optical reprocessing site lies within the inner third of the
accretion disk. This is strikingly different from other cataclysmic variables,
where much or all of the disk contributes to the optical oscillations.Comment: 16 pages including 3 tables and 4 encapsulated postscript figures;
LaTeX format, uses aastex.cls; accepted on 2001 August 2 for publication in
The Astrophysical Journa
Spindown of massive rotating stars
Models of rapidly rotating massive stars at low metallicities show
significantly different evolution and higher metal yields compared to
non-rotating stars. We estimate the spin-down time-scale of rapid rotating
non-convective stars supporting an alpha-Omega dynamo. The magnetic dynamo
gives rise to mass loss in a magnetically controlled stellar wind and hence
stellar spin down owing to loss of angular momentum. The dynamo is maintained
by strong horizontal rotation-driven turbulence which dominates over the Parker
instability. We calculate the spin-down time-scale and find that it could be
relatively short, a small fraction of the main-sequence lifetime. The spin-down
time-scale decreases dramatically for higher surface rotations suggesting that
rapid rotators may only exhibit such high surface velocities for a short time,
only a small fraction of their main-sequence lifetime.Comment: Accepted by MNRA
Atomic Structure and Dynamics of Single Platinum Atom Interactions with Monolayer MoS
We have studied atomic level interactions between single Pt atoms and the surface of monolayer MoS₂ using aberration-corrected annular dark field scanning transmission electron microscopy at an accelerating voltage of 60 kV. Strong contrast from single Pt atoms on the atomically resolved monolayer MoS₂ lattice enables their exact position to be determined with respect to the MoS₂ lattice, revealing stable binding sites. In regions of MoS₂ free from surface contamination, the Pt atoms are localized in S vacancy sites and exhibit dynamic hopping to nearby vacancy sites driven by the energy supplied by the electron beam. However, in areas of MoS₂ contaminated with carbon surface layers, the Pt atoms appear at various positions with respect to the underlying MoS₂ lattice, including on top of Mo and in off-axis positions. These variations are due to the Pt bonding with the surrounding amorphous carbon layer, which disrupts the intrinsic Pt-MoS₂ interactions, leading to more varied positions. Density functional theory (DFT) calculations reveal that Pt atoms on the surface of MoS₂ have a small barrier for migration and are stabilized when bound to either a single or double sulfur vacancies. DFT calculations have been used to understand how the catalytic activity of the MoS₂ basal plane for hydrogen evolution reaction is influenced by Pt dopants by variation of the hydrogen adsorption free energy. This strong dependence of catalytic effect on interfacial configurations is shown to be common for a series of dopants, which may provide a means to create and optimize reaction centers
Clergy work-related satisfactions in parochial ministry: the influence of personality and churchmanship
The aim of this study was to test several hypotheses that clergy work-related satisfaction could be better explained by a multidimensional rather than a unidimensional model. A sample of 1071 male stipendiary parochial clergy in the Church of England completed the Clergy Role Inventory, together with the short-form Revised Eysenck Personality Questionnaire. Factor analysis of the Clergy Role Inventory identified five separate clergy roles: Religious Instruction, Administration, Statutory Duties (conducting marriages and funerals), Pastoral Care, and Role Extension (including extra-parochial activities). Respondents also provided an indication of their predispositions on the catholic-evangelical and liberal-conservative dimensions. The significant associations of the satisfactions derived from each of the roles with the demographic, personality, and churchmanship variables were numerous, varied, and, with few exceptions, small in magnitude. Separate hierarchical regressions for each of the five roles indicated that the proportion of total variance explained by churchmanship was, in general, at least as great as that explained by personality, and was greater for three roles: Religious Instruction, Statutory Duties, and Role Extension. It was concluded that clergy satisfactions derived from different roles are not uniform and that churchmanship is at least as important as personality in accounting for clergy work satisfaction
Mapping nanoscale electrostatic field fluctuations around graphene dislocation cores using four-dimensional scanning transmission electron microscopy (4D-STEM)
Defects in crystalline lattices cause modulation of the atomic density, and this leads to variations in the associated electrostatics at the nanoscale. Mapping these spatially varying charge fluctuations using transmission electron microscopy has typically been challenging due to complicated contrast transfer inherent to conventional phase contrast imaging. To overcome this, we used four-dimensional scanning transmission electron microscopy (4D-STEM) to measure electrostatic fields near point dislocations in a monolayer. The asymmetry of the atomic density in a (1,0) edge dislocation core in graphene yields a local enhancement of the electric field in part of the dislocation core. Through experiment and simulation, the increased electric field magnitude is shown to arise from "long-range" interactions from beyond the nearest atomic neighbor. These results provide insights into the use of 4D-STEM to quantify electrostatics in thin materials and map out the lateral potential variations that are important for molecular and atomic bonding through Coulombic interactions
Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities
Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of American 112 (2015): 13184-13189, doi: 10.1073/pnas.1511474112
.Hundreds of organic chemicals are utilized during natural gas extraction via high volume
hydraulic fracturing (HVHF). However, it is unclear if these chemicals, injected into deep
shale horizons, reach shallow groundwater aquifers and impact local water quality, either
from deep underground injection sites or from the surface or shallow subsurface. Here,
we report detectable levels of organic compounds in shallow groundwater samples from
private residential wells overlying the Marcellus Shale in northeastern Pennsylvania.
Analyses of purgeable and extractable organic compounds from 64 groundwater samples
revealed trace levels of volatile organic compounds, well below the Environmental
Protection Agency’s maximum contaminant levels, and low levels of both gasoline range
(GRO; 0-8 ppb) and diesel range organic compounds (DRO; 0-157 ppb). A compound-specific analysis revealed the presence of bis(2-ethylhexyl)phthalate, which is a disclosed
HVHF additive, that was notably absent in a representative geogenic water sample and
field blanks. Pairing these analyses with 1) inorganic chemical fingerprinting of deep
saline groundwater, 2) characteristic noble gas isotopes, and 3) spatial relationships
between active shale gas extraction wells and wells with disclosed environmental health
and safety (EHS) violations, we differentiate between a chemical signature associated
with naturally occurring saline groundwater and a one associated with alternative
anthropogenic routes from the surface (e.g., accidental spills or leaks). The data support a
transport mechanism of DRO to groundwater via accidental release of fracturing fluid
chemicals derived from the surface rather than subsurface flow of these fluids from the
underlying shale formation.The authors thank Duke University’s Pratt School of Engineering
and the National Science Foundation’s CBET Grant Number 1336702 and NSF EAGER
(EAR-1249255) for financial support.2016-04-1
Taxing the Informal Economy: The Current State of Knowledge and Agendas for Future Research
This paper reviews the literature on taxation of the informal economy, taking stock of key debates
and drawing attention to recent innovations. Conventionally, the debate on whether to tax has frequently focused
on the limited revenue potential, high cost of collection, and potentially adverse impact on small firms. Recent
arguments have increasingly emphasised the more indirect benefits of informal taxation in relation to economic
growth, broader tax compliance, and governance. More research is needed, we argue, into the relevant costs and
benefits for all, including quasi-voluntary compliance, political and administrative incentives for reform, and
citizen-state bargaining over taxation
Arbitrarily Degenerate Helium White Dwarfs as Donors in AM CVn Binaries
We apply the Deloye & Bildsten (2003) isentropic models for donors in
ultracompact low-mass X-ray binaries to the AM CVn population of ultracompact,
interacting binaries. The mass-radius relations of these systems' donors in the
mass range of interest (M_2<0.1 \msun) are not single-valued, but
parameterized by the donor's specific entropy. This produces a range in the
relationships between system observables, such as orbital period, \Porb, and
mass transfer rate, \Mdot. For a reasonable range in donor specific entropy,
\Mdot can range over several orders of magnitude at fixed \Porb. We
determine the unique relation between \Mdot and in the AM CVn systems
with known donor to accretor mass ratios, . We use structural
arguments, as well as each system's photometric behavior, to place limits on
\Mdot and in each. Most systems allow a factor of about 3 variation in
\Mdot, although V803 Cen, if the current estimates of its are accurate,
is an exception and must have M_2 \approx 0.02 \msun and \Mdot \approx
10^{-10} \msun yr. Our donor models also constrain each donor's core
temperature, , range and correlate with . We examine how
variations in donor specific entropy across the white dwarf family
\citep{nele01a} of AM CVn systems affects this population's current galactic
distribution. Allowing for donors that are not fully degenerate produces a
shift in systems towards longer \Porb and higher \Mdot increasing the
parameter space in which these systems can be found. This shift increases the
fraction of systems whose \Porb is long enough that their gravity wave (GW)
signal is obscured by the background of detached double white dwarf binaries
that dominate the GW spectrum below a frequency mHz.Comment: 13 pages, 10 figures, uses emulateapj.cls. Accepted to Astrophysical
Journa
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