6,151 research outputs found
The impairing effect of acute stress on suppression-induced forgetting of future fears and its moderation by working memory capacity
Unwanted imaginations of future fears can, to some extent, be avoided. This is achieved by control mechanisms similar to those engaged to suppress and forget unwanted memories. Suppression-induced forgetting relies on the executive control network, whose functioning is impaired after exposure to acute stress. This study investigates whether acute stress affects the ability to intentionally control future fears and, furthermore, whether individual differences in executive control predict a susceptibility to these effects. The study ran over two consecutive days. On day 1, the working memory capacity of one hundred participants was assessed. Thereafter, participants provided descriptions and details of fearful episodes that they imagined might happen in their future. On day 2, participants were exposed to either the stress or no-stress version of the Maastricht Acute Stress Test, after which participants performed the Imagine/No-Imagine task. Here, participants repeatedly imagined some future fears and suppressed imaginings of others. Results demonstrated that, in unstressed participants, suppression successfully induced forgetting of the episodes’ details compared to a baseline condition. However, anxiety toward these events did not differ. Acute stress was found to selectively impair suppression-induced forgetting and, further, this effect was moderated by working memory capacity. Specifically, lower working memory predicted a susceptibility to these detrimental effects. These findings provide novel insights into conditions under which our capacity to actively control future fears is reduced, which may have considerable implications for understanding stress-related psychopathologies and symptomatologies characterized by unwanted apprehensive thoughts
Missing Mechanisms of Manipulation in the EU AI Act
The European Union Artificial Intelligence (AI) Act proposes to ban AI systems that ”manipulate persons through subliminal techniques or exploit the fragility of vulnerable individuals, and could potentially harm the manipulated individual or third person”. This article takes the perspective of cognitive psychology to analyze and understand what algorithmic manipulation consists of, who vulnerable individuals may be, and what is considered as harm. Subliminal techniques are expanded with concepts from behavioral science and the study of preference change. Individual psychometric differences which can be exploited are used to expand the concept of vulnerable individuals. The concept of harm is explored beyond physical and psychological harm to consider harm to one’s time and right to an un-manipulated opinion. The paper offers policy recommendations that extend from the paper’s analyses
Spectral analysis for compressible quantum fluids
Turbulent fluid dynamics typically involves excitations on many different
length scales. Classical incompressible fluids can be cleanly represented in
Fourier space enabling spectral analysis of energy cascades and other
turbulence phenomena. In quantum fluids, additional phase information and
singular behaviour near vortex cores thwarts the direct extension of standard
spectral techniques. We develop a formal and numerical spectral analysis for
symmetry-breaking quantum fluids suitable for analyzing turbulent flows,
with specific application to the Gross-Pitaevskii fluid. Our analysis builds
naturally on the canonical approach to spectral analysis of velocity fields in
compressible quantum fluids, and establishes a clear correspondence between
energy spectral densities, power spectral densities, and autocorrelation
functions, applicable to energy residing in velocity, quantum pressure,
interaction, and potential energy of the fluid. Our formulation includes all
quantum phase information and also enables arbitrary resolution spectral
analysis, a valuable feature for numerical analysis. A central vortex in a
trapped planar Bose-Einstein condensate provides an analytically tractable
example with spectral features of interest in both the infrared and ultraviolet
regimes. Sampled distributions modelling the dipole gas, plasma, and clustered
regimes exhibit velocity correlation length increasing with vortex energy,
consistent with known qualitative behaviour across the vortex clustering
transition. The spectral analysis of compressible quantum fluids presented here
offers a rigorous tool for analysing quantum features of superfluid turbulence
in atomic or polariton condensates.Comment: 17 pages. Fixed error in appendix C presentation, added references.
Results and conclusions unchange
SYSTEMS-2: a randomised phase II study of radiotherapy dose escalation for pain control in malignant pleural mesothelioma
SYSTEMS-2 is a randomised study of radiotherapy dose escalation for pain control in 112 patients with malignant pleural mesothelioma (MPM). Standard palliative (20Gy/5#) or dose escalated treatment (36Gy/6#) will be delivered using advanced radiotherapy techniques and pain responses will be compared at week 5. Data will guide optimal palliative radiotherapy in MPM
Diffractive Contribution to the Elasticity and the Nucleonic Flux in the Atmosphere
We calculate the average elasticity considering non-diffractive and single
diffractive interactions and perform an analysis of the cosmic-ray flux by
means of an analytical solution for the nucleonic diffusion equation. We show
that the diffractive contribution is important for the adequate description of
the nucleonic and hadronic fluxes in the atmosphere.Comment: 10 pages, latex, 2 figures (uuencoded PostScript
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The Palaeolithic record of Warsash, Hampshire, UK: implications for late Lower and early Middle Palaeolithic occupation history of Southern Britain
This paper presents new work on the Lower and Middle Palaeolithic assemblages recovered from Pleistocene gravels of the River Test at Warsash, Hampshire. Historic map and artefact analyses enable the geological context to be established for substantial portions of the Warsash Palaeolithic record, which, when combined with new data relating to regional terrace stratigraphy and chronology, enables Warsash to be incorporated within regional and national Palaeolithic frameworks. Three key assemblages
are identified: (1) a handaxe-dominated assemblage associated with gravels of the Lower Warsash Terrace that is likely to relate to hominin occupation during MIS 9; (2) a Levallois assemblage probably related to sediments overlying the Lower Warsash Terrace and likely to represent occupation in late MIS 8 and/or MIS 7; (3) a handaxe-dominated assemblage recovered from gravels of the Hamble Terrace, which is likely to have been reworked from older terrace fragments. The presence at Warsash of ficrons, cleavers and plano-convex handaxes is confirmed and their potential chronological significance considered. The Levallois record of the Solent Basin is discussed, highlighting its impoverished nature relative to the rich Levallois record of the Thames Valley. It is argued that preservation bias and/or collection history have not played a major role in creating these differences. Instead, it is likely to represent the limited dispersal of Neanderthal populations further into Britain from an entry point in the southern North Sea Basin
Ex Vivo Modeling of Chemical Synergy in Prenatal Kidney Cystogenesis
Cyclic adenosine monophosphate (cAMP) drives genetic polycystic kidney disease (PKD) cystogenesis. Yet within certain PKD families, striking differences in disease severity exist between affected individuals, and genomic and/or environmental modifying factors have been evoked to explain these observations. We hypothesized that PKD cystogenesis is accentuated by an aberrant fetal milieu, specifically by glucocorticoids. The extent and nature of cystogenesis was assessed in explanted wild-type mouse embryonic metanephroi, using 8-Br-cAMP as a chemical to mimic genetic PKD and the glucocorticoid dexamethasone as the environmental modulator. Cysts and glomeruli were quantified by an observer blinded to culture conditions, and tubules were phenotyped using specific markers. Dexamethasone or 8-Br-cAMP applied on their own produced cysts predominantly arising in proximal tubules and descending limbs of loops of Henle. When applied together, however, dexamethasone over a wide concentration range synergized with 8-Br-cAMP to generate a more severe, glomerulocystic, phenotype; we note that prominent glomerular cysts have been reported in autosomal dominant PKD fetal kidneys. Our data support the idea that an adverse antenatal environment exacerbates renal cystogenesis
Vortex generation in stirred binary Bose-Einstein condensates
The dynamical vortex production, with a trap-confining time-dependent stirred
potential, is studied by using mass-imbalanced cold-atom coupled Bose-Einstein
condensates (BEC). The vortex formation is explored by considering that both
coupled species are confined by a pancake-like harmonic trap, slightly modified
elliptically by a time-dependent periodic potential, with the characteristic
frequency enough larger than the transversal trap frequency. The approach is
applied to the experimentally accessible binary mixtures Rb-Cs
and Rb-Rb, which allow us to verify the effect of mass
differences in the dynamics. For both species, the time evolutions of the
respective energy contributions, together with associated velocities, are
studied in order to distinguish turbulent from non-turbulent flows. By using
the angular momentum and moment of inertia mean values, effective classical
rotation frequencies are suggested, which are further considered within
simulations in the rotating frame without the stirring potential. Spectral
analysis is also provided for both species, with the main focus being the
incompressible kinetic energies. In the transient turbulent regime, before
stable vortex patterns are produced, the characteristic Kolmogorov
behavior is clearly identified for both species at intermediate momenta
above the inverse Thomas-Fermi radial positions, further modified by the
universal scaling at momenta higher than the inverse of the respective
healing lengths.
Emerging from the mass-imbalanced comparison, relevant is to observe that, as
larger is the mass difference, much faster is the dynamical production of
stable vortices.Comment: 17 pages, 16 figure
Activity of different desoximetasone preparations compared to other topical corticosteroids in the vasoconstriction assay
Introduction: We report on a double-blind, vehicle-controlled, single-center confirmatory study with random assignment. The purpose of the study was to investigate the topical bioavailability of different topical corticosteroid formulations in healthy human beings focussing on desoximetasone (DM). Materials and Methods: Two DM 0.25% formulations {[}ointment (DM-o) and fatty ointment (DM-fo, water-free); class III corticosteroids], the corresponding active ingredient-free vehicles and three comparators of different strength {[}clobetasol propionate 0.05% (CP 0.05%), fatty ointment, class IV; hydrocortisone (HC) 1%, fatty ointment, class I, and betamethasone (BM) 0.05%, fatty ointment, class III] were tested using the vasoconstriction assay. The degree of vasoconstriction (blanching) in the treatment field was compared to the one found in untreated control fields using chromametric measurements and clinical assessment. Results/Conclusion: DM-o 0.25%, DM-fo 0.25% and BM 0.05% showed similar vasoconstrictive potential, i.e., clear blanching. In fact, both DM preparations were proven to be non-inferior to BM 0.05%, while CP 0.05% was found a little less active. HC 1.0% and the DM vehicles showed no clear-cut vasoconstrictive effect. No adverse events related to the study medications were observed. Good topical bioavailability of both DM formulations was detected by chromametric measurement and clinical assessment. Copyright (C) 2008 S. Karger AG, Basel
Screening men for abdominal aortic aneurysm: 10 year mortality and cost effectiveness results from the randomised Multicentre Aneurysm Screening Study
Objectives To assess whether the mortality benefit from screening men aged 65-74 for abdominal aortic aneurysm decreases over time, and to estimate the long term cost effectiveness of screening
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