285 research outputs found
On Loops in Inflation II: IR Effects in Single Clock Inflation
In single clock models of inflation the coupling between modes of very
different scales does not have any significant dynamical effect during
inflation. It leads to interesting projection effects. Larger and smaller modes
change the relation between the scale a mode of interest will appear in the
post-inflationary universe and will also change the time of horizon crossing of
that mode. We argue that there are no infrared projection effects in physical
questions, that there are no effects from modes of longer wavelength than the
one of interest. These potential effects cancel when computing fluctuations as
a function of physically measurable scales. Modes on scales smaller than the
one of interest change the mapping between horizon crossing time and scale. The
correction to the mapping computed in the absence of fluctuations is enhanced
by a factor N_e, the number of e-folds of inflation between horizon crossing
and reheating. The new mapping is stochastic in nature but its variance is not
enhanced by N_e.Comment: 13 pages, 1 figure; v2: JHEP published version, added minor comments
and reference
On Loops in Inflation III: Time Independence of zeta in Single Clock Inflation
Studying loop corrections to inflationary perturbations, with particular
emphasis on infrared factors, is important to understand the consistency of the
inflationary theory, its predictivity and to establish the existence of the
slow-roll eternal inflation phenomena and its recently found volume bound. In
this paper we prove that the zeta correlation function is time-independent at
one-loop level in single clock inflation. While many of the one-loop diagrams
lead to a time-dependence when considered individually, the time-dependence
beautifully cancels out in the overall sum. We identify two subsets of diagrams
that cancel separately due to different physical reasons. The first
cancellation is related to the change of the background cosmology due to the
renormalization of the stress tensor. It results in a cancellation between the
non-1PI diagrams and some of the diagrams made with quartic vertices. The
second subset of diagrams that cancel is made up of cubic operators, plus the
remaining quartic ones. We are able to write the sum of these diagrams as the
integral over a specific three-point function between two very short
wavelengths and one very long one. We then apply the consistency condition for
this three-point function in the squeezed limit to show that the sum of these
diagrams cannot give rise to a time dependence. This second cancellation is
thus a consequence of the fact that in single clock inflation the attractor
nature of the solution implies that a long wavelength zeta perturbation is
indistinguishable from a trivial rescaling of the background, and so results in
no physical effect on short wavelength modes.Comment: 47 pages, 7 figures; v2: JHEP published version, typos and minor
correction
Towards multi-scale dynamics on the baryonic branch of Klebanov-Strassler
We construct explicitly a new class of backgrounds in type-IIB supergravity
which generalize the baryonic branch of Klebanov-Strassler. We apply a
solution-generating technique that, starting from a large class of solutions of
the wrapped-D5 system, yields the new solutions, and then proceed to study in
detail their properties, both in the IR and in the UV. We propose a simple
intuitive field theory interpretation of the rotation procedure and of the
meaning of our new solutions within the Papadopoulos-Tseytlin ansatz, in
particular in relation to the duality cascade in the Klebanov-Strassler
solution. The presence in the field theory of different VEVs for operators of
dimensions 2, 3 and 6 suggests that this is an important step towards the
construction of the string dual of a genuinely multi-scale (strongly coupled)
dynamical model.Comment: 37 pages, 7 figures. References added, version to appear in JHE
How do you say âhelloâ? Personality impressions from brief novel voices
On hearing a novel voice, listeners readily form personality impressions of that speaker. Accurate or not, these impressions are known to affect subsequent interactions; yet the underlying psychological and acoustical bases remain poorly understood. Furthermore, hitherto studies have focussed on extended speech as opposed to analysing the instantaneous impressions we obtain from first experience. In this paper, through a mass online rating experiment, 320 participants rated 64 sub-second vocal utterances of the word âhelloâ on one of 10 personality traits. We show that: (1) personality judgements of brief utterances from unfamiliar speakers are consistent across listeners; (2) a two-dimensional âsocial voice spaceâ with axes mapping Valence (Trust, Likeability) and Dominance, each driven by differing combinations of vocal acoustics, adequately summarises ratings in both male and female voices; and (3) a positive combination of Valence and Dominance results in increased perceived male vocal Attractiveness, whereas perceived female vocal Attractiveness is largely controlled by increasing Valence. Results are discussed in relation to the rapid evaluation of personality and, in turn, the intent of others, as being driven by survival mechanisms via approach or avoidance behaviours. These findings provide empirical bases for predicting personality impressions from acoustical analyses of short utterances and for generating desired personality impressions in artificial voices
Social inequalities and correlates of psychotropic drug use among young adults: a population-based questionnaire study
<p>Abstract</p> <p>Background</p> <p>Use of psychotropic drugs is widespread in Europe, and is markedly more common in France than elsewhere. Young adults often fare less well than adolescents on health indicators (injury, homicide, and substance use). This population-based study assessed disparities in psychotropic drug use among people aged 18â29 from different socio-occupational groups and determined whether they were mediated by educational level, health status, income, health-related behaviours, family support, personality traits, or disability.</p> <p>Methods</p> <p>A total of 1,257 people aged 18â29, randomly selected in north-eastern France completed a post-mailed questionnaire covering sex, date of birth, height, weight, educational level, occupation, smoking habit, alcohol abuse, income, health-status, diseases, reported disabilities, self-reported personality traits, family support, and frequent psychotropic medication for tiredness, nervousness/anxiety or insomnia. The data were analyzed using the adjusted odds ratios (ORa) computed with logistic models.</p> <p>Results</p> <p>Use of psychotropic drugs was common (33.2%). Compared with upper/intermediate professionals, markedly high odds ratios adjusted for sex were found for manual workers (2.57, 95% CI 1.02â6.44), employees (2.58, 1.11â5.98), farmers/craftsmen/tradesmen (4.97, 1.13â21.8), students (2.40, 1.06â5.40), and housewives (3.82, 1.39â10.5). Adjusting for all the confounders considered reduced the estimates to a pronounced degree for manual workers (adjusted OR 1.49, non-significant) but only slightly for the other socio-occupational groups. The odds ratio for unemployed people did not reach statistical significance. The significant confounders were: sex, not-good health status, musculoskeletal disorders and other diseases, being worried, nervous or sad, and lack of family support (adjusted odds ratios between 1.60 and 2.50).</p> <p>Conclusion</p> <p>There were marked disparities among young adults from different socio-occupational groups. Sex, health status, musculoskeletal diseases, family support, and personality traits were related to use of psychotropic drugs. These factors mediated the higher risk strongly among manual workers and slightly among the other groups.</p
The everpresent eta-problem: knowledge of all hidden sectors required
We argue that the eta-problem in supergravity inflation cannot be solved
without knowledge of the ground state of hidden sectors that are
gravitationally coupled to the inflaton. If the hidden sector breaks
supersymmetry independently, its fields cannot be stabilized during
cosmological evolution of the inflaton. We show that both the subsequent
dynamical mixing between sectors as well as the lightest mass of the hidden
sector are set by the scale of supersymmetry breaking in the hidden sector. The
true cosmological eta-parameter arises from a linear combination of the
lightest mode of the hidden sector with the inflaton. Generically, either the
true eta deviates considerably from the na\"ive eta implied by the inflaton
sector alone, or one has to consider a multifield model. Only if the lightest
mass in the hidden sector is much larger than the inflaton mass and if the
inflaton mass is much larger than the scale of hidden sector supersymmetry
breaking, is the effect of the hidden sector on the slow-roll dynamics of the
inflaton negligible.Comment: 27 pages, 6 figures; v2, published version, minor adjustments to the
introduction, minor corrections to section 2.2 for improved clarity,
references adde
Drivers of grassland loss in Hungary during the post-socialist transformation (1987â1999)
The increase in the speed of land-cover change experienced worldwide is becoming a growing
concern. Major socio-economic transitions, such as the breakdown of socialism in Europe, may
lead to particularly high rates of landscape transformations. In this paper we examined the loss of semi-natural grasslands in Hungary between 1987 and 1999. We studied the relationship between 9
potential driving forces and the fate of grasslands using logistic GLMs.
Grassland loss was found to be very high (1.31 % per year), which is far higher than either before
or after this period. The most influential predictors of grassland loss were environmental and
landscape characteristics (soil type, area of remnant grassland patches), and the socio-economic context (distance to paved road, and nearest settlement, human population density). Several
processes and relationships can only be understood from a historical perspective (e.g. large extent
of afforestation, strong decrease of soil water table). Grassland loss during the study period
emerged as a consequence of survival strategies of individual farmers seeking adaptation to the
changing environmental and socio-economic conditions, and not urbanization and agricultural intensification which are the main underlying drivers for the ongoing landscape transformations in
most parts of the developed world.
Though globalization increasingly influences local land use decisions , reconstructing and
modelling recent landscape changes cannot be done without a proper understanding of local history
and culture. Our analysis shows the importance of large-area yet high resolution landscape change research, which may reveal unexpected patterns of land cover change, undetected at coarser scales
Cardiac afferent activity modulates the expression of racial stereotypes
Negative racial stereotypes tend to associate Black people with threat. This often leads to the misidentification of harmless objects as weapons held by a Black individual. Yet, little is known about how bodily states impact the expression of racial stereotyping. By tapping into the phasic activation of arterial baroreceptors, known to be associated with changes in the neural processing of fearful stimuli, we show activation of race-threat stereotypes synchronized with the cardiovascular cycle. Across two established tasks, stimuli depicting Black or White individuals were presented to coincide with either the cardiac systole or diastole. Results show increased race-driven misidentification of weapons during systole, when baroreceptor afferent firing is maximal, relative to diastole. Importantly, a third study examining the positive Black-athletic stereotypical association fails to demonstrate similar modulations by cardiac cycle. We identify a bodyâbrain interaction wherein interoceptive cues can modulate threat appraisal and racially biased behaviour in context-dependent ways
Interactions of Cathinone NPS with Human Transporters and Receptors in Transfected Cells
Pharmacological assays carried out in transfected cells have been very useful for describing the mechanism of action of cathinone new psychoactive substances (NPS). These in vitro characterizations provide fast and reliable information on psychoactive substances soon after they emerge for recreational use. Well-investigated comparator compounds, such as methamphetamine, 3,4-methylenedioxymethamphetamine, cocaine, and lysergic acid diethylamide, should always be included in the characterization to enhance the translation of the in vitro data into clinically useful information. We classified cathinone NPS according to their pharmacology at monoamine transporters and receptors. Cathinone NPS are monoamine uptake inhibitors and most induce transporter-mediated monoamine efflux with weak to no activity at pre- or postsynaptic receptors. Cathinones with a nitrogen-containing pyrrolidine ring emerged as NPS that are extremely potent transporter inhibitors but not monoamine releasers. Cathinones exhibit clinically relevant differences in relative potencies at serotonin vs. dopamine transporters. Additionally, cathinone NPS have more dopaminergic vs. serotonergic properties compared with their non-ÎČ-keto amphetamine analogs, suggesting more stimulant and reinforcing properties. In conclusion, in vitro pharmacological assays in heterologous expression systems help to predict the psychoactive and toxicological effects of NPS
Health-related quality of life in French adolescents and adults: norms for the DUKE Health Profile
<p>Abstract</p> <p>Background</p> <p>The continual monitoring of population health-related quality of life (HRQoL) with validated instruments helps public health agencies assess, protect, and promote population health. This study aimed to determine norms for the French adolescent and adult general population for the Duke Health Profile (DUKE) questionnaire in a large representative community sample.</p> <p>Methods</p> <p>We randomly selected 17,733 French people aged 12 to 75 years old in 2 steps, by households and individuals, from the National Health Barometer 2005, a periodic population study by the French National Institute for Prevention and Health Education. Quality of life and other data were collected by computer-assisted telephone interview.</p> <p>Results</p> <p>Normative data for the French population were analyzed by age, gender and self-reported chronic disease. Globally, function scores (best HRQoL=100) for physical, mental, social, and general health, as well as perceived health and self-esteem, were 72.3 (SEM 0.2), 74.6 (0.2), 66.8 (0.1), 71.3 (0.1), 71.3 (0.3), 76.5 (0.1), respectively. Dysfunction scores (worst HRQoL=100) for anxiety, depression, pain and disability domains were 30.9 (0.1), 27.6 (0.2), 34.3 (0.3), 3.1 (0.1), respectively.</p> <p>Conclusion</p> <p>The French norms for adolescents and adults for the DUKE could be used as a reference for other studies assessing HRQoL, for specific illnesses, in France and for international comparisons.</p
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