1,271 research outputs found
Elastic and Raman scattering of 9.0 and 11.4 MeV photons from Au, Dy and In
Monoenergetic photons between 8.8 and 11.4 MeV were scattered elastically and
in elastically (Raman) from natural targets of Au, Dy and In.15 new cross
sections were measured. Evidence is presented for a slight deformation in the
197Au nucleus, generally believed to be spherical. It is predicted, on the
basis of these measurements, that the Giant Dipole Resonance of Dy is very
similar to that of 160Gd. A narrow isolated resonance at 9.0 MeV is observed in
In.Comment: 31 pages, 11 figure
The Value of Sex in Procreative Reasons
Copyright Taylor and Francis Group, LLC. This is an open access article distributed under the Supplemental Terms and Conditions for iOpenAccess articles published in Taylor & Francis journals, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Functional neuroimaging and withdrawal of life-sustaining treatment from vegetative patients
Recent studies using functional magnetic resonance imaging of patients in a vegetative state have raised the possibility that such patients retain some degree of consciousness. In this paper, the ethical implications of such findings are outlined, in particular in relation to decisions about withdrawing life-sustaining treatment. It is sometimes assumed that if there is evidence of consciousness, treatment should not be withdrawn. But, paradoxically, the discovery of consciousness in very severely brain-damaged patients may provide more reason to let them die. Although functional neuroimaging is likely to play an increasing role in the assessment of patients in a vegetative state, caution is needed in the interpretation of neuroimaging findings
Estimates in Beurling--Helson type theorems. Multidimensional case
We consider the spaces of functions on the
-dimensional torus such that the sequence of the Fourier
coefficients belongs to
. The norm on is defined by
. We study the rate of
growth of the norms as
for -smooth real
functions on (the one-dimensional case was investigated
by the author earlier). The lower estimates that we obtain have direct
analogues for the spaces
Weak radiative corrections to the Drell-Yan process for large invariant mass of a dilepton pair
The weak radiative corrections to the Drell-Yan process above the Z-peak have
been studied. The compact asymptotic expression for the two heavy boson
exchange - one of the significant contributions to the investigated process -
has been obtained, the results expand in the powers of the Sudakov electroweak
logarithms. At the quark level we compare the weak radiative corrections to the
total cross section and forward-backward asymmetry with the existing results
and achieve a rather good coincidence at \sqrt{s}>= 0.5 TeV. The numerical
analysis has been performed in the high energy region corresponding to the
future experiments at the CERN Large Hadron Collider (LHC). To simulate the
detector acceptance we used the standard CMS detector cuts. It was shown that
double Sudakov logarithms of the WW boxes are the dominant contributions in
hadronic cross section. The considered radiative corrections are significant at
high dilepton mass M and change the dilepton mass distribution up to ~+3(-12)%
at the LHC energies and M=1(5) TeV.Comment: Changed content; 13 pp, 4 fig, 1 tabl
Doing good by doing nothing? The role of social norms in explaining default effects in altruistic contexts
We explore whether the known preference for default options in choice contexts—default effects—occur in altruistic contexts and the extent to which this can be explained through appeal to social norms. In four experiments, we found that (i) participants were more likely to donate money to charity when this was the default option in an altruistic choice context; (ii) participants perceived the default option to be the socially normative option; (iii) perceptions of social norms mediated the relationship between default status and charitable donations; and (iv) a transfer effect, whereby participants translated social norms they inferred from the default option in one domain into behavior in a second, related domain. Theoretically, our analysis situates default effects within a comprehensive body of social psychological research concerning social norms and the attitude‐behavior relationship, providing novel empirical predictions. Practically, these findings highlight that the way donation policies are framed can have an important impact on donation behavior: in our third study, we found that 81% donated half of their earnings for taking part in the experiment to charity when this was the default option, compared with only 19% when keeping the money was the default. Our work suggests that making use of default effects could be an effective tool to increase altruistic behavior without compromising freedo
Concern for others leads to vicarious optimism
An optimistic learning bias leads people to update their beliefs in response to better-than-expected good news but neglect worse-than-expected bad news. Because evidence suggests that this bias arises from self-concern, we hypothesized that a similar bias may affect beliefs about other people’s futures, to the extent that people care about others. Here, we demonstrated the phenomenon of vicarious optimism and showed that it arises from concern for others. Participants predicted the likelihood of unpleasant future events that could happen to either themselves or others. In addition to showing an optimistic learning bias for events affecting themselves, people showed vicarious optimism when learning about events affecting friends and strangers. Vicarious optimism for strangers correlated with generosity toward strangers, and experimentally increasing concern for strangers amplified vicarious optimism for them. These findings suggest that concern for others can bias beliefs about their future welfare and that optimism in learning is not restricted to oneself
Propranolol reduces implicit negative racial bias.
BACKGROUND: Implicit negative attitudes towards other races are important in certain kinds of prejudicial social behaviour. Emotional mechanisms are thought to be involved in mediating implicit "outgroup" bias but there is little evidence concerning the underlying neurobiology. The aim of the present study was to examine the role of noradrenergic mechanisms in the generation of implicit racial attitudes. METHODS: Healthy volunteers (n = 36) of white ethnic origin, received a single oral dose of the β-adrenoceptor antagonist, propranolol (40 mg), in a randomised, double-blind, parallel group, placebo-controlled, design. Participants completed an explicit measure of prejudice and the racial implicit association test (IAT), 1-2 h after propranolol administration. RESULTS: Relative to placebo, propranolol significantly lowered heart rate and abolished implicit racial bias, without affecting the measure of explicit racial prejudice. Propranolol did not affect subjective mood. CONCLUSIONS: Our results indicate that β-adrenoceptors play a role in the expression of implicit racial attitudes suggesting that noradrenaline-related emotional mechanisms may mediate negative racial bias. Our findings may also have practical importance given that propranolol is a widely used drug. However, further studies will be needed to examine whether a similar effect can be demonstrated in the course of clinical treatment
Galactic interstellar 18O/17O ratios - a radial gradient?
(Abridged) Our aim is to determine 18O/17O abundance ratios across the entire
Galaxy. These provide a measure of the amount of enrichment by high-mass versus
intermediate-mass stars. Such ratios, derived from the C18O and C17O J=1-0
lines alone, may be affected by systematic errors. Therefore, the C18O and C17O
(1-0), (2-1), and (3-2), as well as the 13CO (1-0) and (2-1) lines, were
observed towards 18 prominent galactic targets (a total of 25 positions). The
combined dataset was analysed with an LVG model, accounting for optical depth
effects. The data cover galactocentric radii R between 0.1 and 16.9 kpc (solar
circle at 8.5 kpc). Near the centre of the Galaxy, 18O/17O = 2.88 +/- 0.11. For
the galactic disc out to an R of ca. 10 kpc, 18O/17O = 4.16 +/- 0.09. At ca. R
= 16.5 kpc, 18O/17O = 5.03 +/- 0.46. Assuming that 18O is synthesised
predominantly in high-mass stars (M > 8 Msun), while C17O is mainly a product
of lower-mass stars, the ratio from the inner Galaxy indicates a dominance of
CNO-hydrogen burning products that is also apparent in the C- and N-isotope
ratios. The high 18O/17O value of the solar system (5.5) relative to that of
the ambient ISM suggests contamination by nearby high-mass stars during its
formation. High values in the metal-poor environment of the outer Galaxy are
not matched by the low values observed towards the even more metal-poor LMC.
Apparently, the outer Galaxy cannot be considered as an intermediate
environment between the solar neighbourhood and the ISM of small metal-poor
galaxies. The apparent 18O/17O gradient along the galactic disc and the
discrepancy between outer disc and LMC isotope ratios may be explained by
different ages of the respective stellar populations.Comment: Accepted by Astron. & Astroph.; 10 pages + 4 pages on-line material
(figs
Uncertainty about the impact of social decisions increases prosocial behaviour
Uncertainty about how our choices will affect others infuses social life. Past research suggests uncertainty has a negative effect on prosocialbehaviour by enabling people to adopt self-serving narratives about their actions. We show that uncertainty does not always promote selfishness. We introduce a distinction between two types of uncertainty that have opposite effects on prosocial behaviour. Previous work focused on outcome uncertainty (uncertainty about whether or not a decision will lead to a particular outcome). However, as soon as people’s decisions might have negative consequences for others, there is also impact uncertainty (uncertainty about how others’ well-being will be impacted by the negative outcome). Consistent with past research, we found decreased prosocial behaviour under outcome uncertainty. In contrast, prosocial behaviour was increased under impact uncertainty in incentivized economic decisions and hypothetical decisions about infectious disease threats. Perceptions of social norms paralleled the behavioural effects. The effect of impact uncertainty on prosocial behaviour did not depend on the individuation of others or the mere mention of harm, and was stronger when impact uncertainty was made more salient. Our findings offer insights into communicating uncertainty, especially in contexts where prosocial behaviour is paramount, such as responding to infectious disease threats
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