6,080 research outputs found
Constraining the extra heating of the Diffuse Ionized Gas in the Milky Way
The detailed observations of the diffuse ionized gas through the emission
lines H, [NII], and [SII] in the Perseus Arm of our Galaxy by the
Wisconsin H Mapper (WHAM)--survey challenge photoionization models.
They have to explain the observed rise in the line ratios [NII]/H and
[SII]/H. The models described here consider for the first time the
detailed observational geometry toward the Perseus Arm. The models address the
vertical variation of the line ratios up to height of 2 kpc above the midplane.
The rising trends of the line ratios are matched. The increase in the line
ratios is reflected in a rise of the temperature of the gas layer. This is due
to the progressive hardening of the radiation going through the gas. However an
extra heating above photoionization is needed to explain the absolute values.
Two different extra heating rates are investigated which are proportional to
and . The models show that a combination of both are best to explain
the data, where the extra heating independent of density is dominant for z
0.8 kpc.Comment: accepted for publication in Ap
Correlated charge polarization in a chain of coupled quantum dots
Coherent charge transfer in a linear array of tunnel-coupled quantum dots,
electrostatically coupled to external gates, is investigated using the Bethe
ansatz for a symmetrically biased Hubbard chain. Charge polarization in this
correlated system is shown to proceed via two distinct processes: formation of
bound states in the metallic phase, and charge transfer processes corresponding
to a superposition of antibound states at opposite ends of the chain in the
Mott-insulating phase. The polarizability in the insulating phase of the chain
exhibits a universal scaling behavior, while the polarization charge in the
metallic phase of the model is shown to be quantized in units of .Comment: 9 pages, 3 figures, 1 tabl
Simple model for decay of superdeformed nuclei
Recent theoretical investigations of the decay mechanism out of a
superdeformed nuclear band have yielded qualitatively different results,
depending on the relative values of the relevant decay widths. We present a
simple two-level model for the dynamics of the tunneling between the
superdeformed and normal-deformed bands, which treats decay and tunneling
processes on an equal footing. The previous theoretical results are shown to
correspond to coherent and incoherent limits of the full tunneling dynamics.
Our model accounts for experimental data in both the A~150 mass region, where
the tunneling dynamics is coherent, and in the A~190 mass region, where the
tunneling dynamics is incoherent.Comment: 4 page
Technology and Regional Development in the American Context
Many large cities in the developed countries have recently experienced a slow-down of growth, and in some cases, absolute contraction of their population size. These trends pertain in particular to old industrial agglomerations which often fail to adapt to the changing demands and locational requirements of modern production facilities and to differentiate their employment structure.
Interrelations between industrial restructuring and urban regional change were among topics studied in the former Human Settlements and Services Area at IIASA. They are also of current research interest to the Regional and Urban Development Group. The paper by J. Rees, H. Stafford, R. Briggs and R. Oakey touches on several aspects of those interdependencies, especially the question of how do high-technology complexes develop over space.
Part II of the paper has been done within a framework of an international collaboration project involving similar studies in the U.K. and F.R.G. and coordinated by Professor John Goddard of Newcastle, U.K
Effect of vasopressin 1b receptor blockade on the hypothalamic-pituitary-adrenal response of chronically stressed rats to a heterotypic stressor
Exposure to chronic restraint (CR) modifies the hypothalamic–pituitary–adrenal (HPA) axis response to subsequent acute stressors with adaptation of the response to a homotypic and sensitization of the response to a heterotypic stressor. Since vasopressin (AVP) activity has been reported to change during chronic stress, we investigated whether this was an important factor in HPA facilitation. We therefore tested whether vasopressin 1b receptor (AVPR1B) blockade altered the ACTH and corticosterone response to heterotypic stressors following CR stress. Adult male rats were exposed to CR, single restraint, or were left undisturbed in the home cage. Twenty-four hours after the last restraint, rats were injected with either a AVPR1B antagonist (Org, 30 mg/kg, s.c.) or vehicle (5% mulgofen in saline, 0.2/kg, s.c.) and then exposed to either restraint, lipopolysaccharide (LPS) or white noise. CR resulted in the adaptation of the ACTH and corticosterone response to restraint and this effect was not prevented by pretreatment with Org. Although we found no effect of CR on LPS-induced ACTH and corticosterone secretion, both repeated and single episodes of restraint induced the sensitization of the ACTH, but not corticosterone response to acute noise. Pretreatment with Org reduced the exaggerated ACTH response to noise after both single and repeated exposure to restraint
Preliminary analysis of a wake trailing a spacecraft
Using void regions trailing orbiting bodies to conserve propellant of untethered modules flying in formation with mother spacecraf
To blame? The effects of moralized feedback on implicit racial bias
Implicit bias training (IBT) is now frequently provided by employers, in order to raise awareness of the problems related to implicit biases, and of how to safeguard against discrimination that may result. However, as Atewologun et al (2018) have noted, there is very little systematicity in IBT, and there are many unknowns about what constitutes good IBT. One important issue concerns the tone of information provided regarding implicit bias. This paper engages this question, focusing in particular on the observation that much bias training is delivered in exculpatory tone, emphasising that individuals are not to blame for possessing implicit biases. Normative guidance around IBT exhorts
practitioners to adopt this strategy (Moss-Racusin et al 2014). However, existing evidence about the effects of moralized feedback about implicit bias is equivocal (Legault et al 2011; Czopp et al 2006). Through a series of studies, culminating in an experiment with a pre-registered analysis plan, we develop a paradigm for evaluating the impact of moralized feedback on participants’ implicit racial bias scores. We also conducted exploratory analyses of the impact on their moods, and behavioural intentions. Our results indicated that an exculpatory tone, rather than a blaming or neutral tone, did not make participants less resistant to changing their attitudes and behaviours. In fact, participants in the blame condition had significantly stronger explicit intentions to change future behaviour than those in the ‘no feedback’ condition (see experiment 3). These results indicate that considerations of
efficacy do not support the need for implicit bias feedback to be exculpatory. We tease out the implications of these findings, and directions for future research
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