14,198 research outputs found
Understanding jumping to conclusions in patients with persecutory delusions: working memory and intolerance of uncertainty
Background. Persecutory delusions are a key psychotic experience. A reasoning style known as âjumping to conclusionsâ (JTC) â limited information gathering before reaching certainty in decision making â has been identified as a contributory factor in the occurrence of delusions. The cognitive processes that underpin JTC need to be determined in order to develop effective interventions for delusions. In the current study two alternative perspectives were tested: that JTC partially results from impairment in information-processing capabilities and that JTC is a motivated strategy to avoid uncertainty.Method. A group of 123 patients with persistent persecutory delusions completed assessments of JTC (the 60:40 beads task), IQ, working memory, intolerance of uncertainty, and psychiatric symptoms. Patients showing JTC were compared with patients not showing JTC.Results. A total of 30 (24%) patients with delusions showed JTC. There were no differences between patients who did and did not jump to conclusions in overall psychopathology. Patients who jumped to conclusions had poorer working memory performance, lower IQ, lower intolerance of uncertainty and lower levels of worry.Working memory and worry independently predicted the presence of JTC.Conclusions. Hasty decision making in patients with delusions may partly arise from difficulties in keeping information in mind. Interventions for JTC are likely to benefit from addressing working memory performance, while in vivo techniques for patients with delusions will benefit from limiting the demands on working memory. The study provides little evidence for a contribution to JTC from top down motivational beliefs about uncertainty
The application of active controls technology to a generic hypersonic aircraft configuration
Analytical methods are described for the prediction of aerothermoelastic stability of hypersonic aircraft including active control systems. Thermal loads due to aerodynamic heating were applied to the finite element model of the aircraft structure and the thermal effects on flutter were determined. An iterative static aeroelastic trim analysis procedure was developed including thermal effects. And active control technology was assessed for flutter suppression, ride quality improvement, and gust load alleviation to overcome any potential adverse aeroelastic stability or response problems due to aerodynamic heating. A generic hypersonic aircraft configuration was selected which incorporates wing flaps, ailerons, and all moveable fins to be used for active control purposes. The active control system would use onboard sensors in a feedback loop through the aircraft flight control computers to move the surfaces for improved structural dynamic response as the aircraft encounters atmospheric turbulence
Troubles with Bayesianism: An introduction to the psychological immune system
A Bayesian mind is, at its core, a rational mind. Bayesianism is thus well-suited to predict and explain mental processes that best exemplify our ability to be rational. However, evidence from belief acquisition and change appears to show that we do not acquire and update information in a Bayesian way. Instead, the principles of belief acquisition and updating seem grounded in maintaining a psychological immune system rather than in approximating
a Bayesian processor
Avatars:the other side of Proteus's mirror : a study into avatar choice regarding perception
The trend for online interactions, can be regarded as being âanti-so-cially socialâ, meaning that a great deal of time is spent playing, working and socializing with the internet serving as the communication conduit. Within that Virtual Social Environment very deep relationships are formed and maintained without the parties ever having met each other face-to-face. Raising the question how much does the physical appearance of an avatar influence the perception of the person behind it? Are relationships informed by appearance even in the vir-tual world and what implications does that have for second language acquisition? This paper leads to a small-scale research project where a selection of avatars with various racially identifiable characteristics were used to identify which av-atars a second language speaker would feel more at ease interacting with in the target language. The resultant research aims to test three hypotheses regarding preferred avatar choice for second language users based solely on perceptions
Perfectionism and achievement goals in young Finnish ice-hockey players aspiring to make the Under-16 national team
Research on perfectionism suggests that is it useful to differentiate between perfectionistic strivings and perfectionistic concerns. Regarding the 2 x 2 achievement goal framework, the usefulness of this differentiation was recently demonstrated in a study with university student athletes (Stoeber, Stoll, Pescheck, & Otto, 2008, Study 2), in which it was found that perfectionistic strivings were associated with mastery-approach and performance-approach goals and perfectionistic concerns with mastery-avoidance, performance-approach, and performance-avoidance goals. Because the study was largely exploratory and only used non-elite athletes, the aim of the present research was to replicate and extend these findings by investigating a sample of 138 young, elite ice-hockey players, while adding further measures of perfectionism and using structural equation modelling (SEM) to confirm the relationships between perfectionistic strivings, perfectionistic concerns,and the 2 x 2 achievement goals. The SEM results showed that, in elite athletes also, perfectionistic strivings are associated with mastery-approach and performance-approach goals, whereas perfectionistic concerns are associated with masteryavoidance,
performance-approach, and performance-avoidance goals. Our findings corroborate the importance of differentiating between perfectionistic strivings and perfectionistic concerns when studying perfectionism in sports, because
only perfectionistic concerns (and not perfectionistic strivings) are associated with maladaptive patterns of achievement goals
AGN-Induced Cavities in NGC 1399 and NGC 4649
We present an analysis of archival Chandra and VLA observations of the E0
galaxy NGC 1399 and the E2 galaxy NGC 4649 in which we investigate cavities in
the surrounding X-ray emitting medium caused by the central AGN. We calculate
the jet power required for the AGN to evacuate these cavities and find values
of ~8x10^{41} erg/s and ~14x10^{41} erg/s for the lobes of NGC 1399 and
~7x10^{41} erg/s and ~6x10^{41} erg/s for those of NGC 4649. We also calculate
the k/f values for each cavity, where k is the ratio of the total particle
energy to that of electrons radiating in the range of 10 MHz to 10 GHz, and f
is the volume filling factor of the plasma in the cavity. We find that the
values of k/f for the lobes of NGC 1399 are ~93 and ~190, and those of the
lobes of NGC 4649 are ~15000 and ~12000. We conclude that the assumed spectrum
describes the electron distribution in the lobes of NGC 1399 reasonably well,
and that there are few entrained particles. For NGC 4649, either there are many
entrained particles or the model spectrum does not accurately describe the
population of electrons.Comment: 8 pages, 2 figures, accepted for publication in MNRA
Collagen Deposition During Wound Repair
Collagen fiber diameters, amount of birefringent collagen (brightness) and birefringence retardation were measured in implanted collagen-based sponges containing hyaluronic acid (HA) and fibronectin (FN). In the presence of HA and FN, increased number of fibroblasts and brightness were observed 6 days after wounding. Increased brightness in the presence of HA and FN reflected increased deposition of oriented collagen fibers. From days 9 to 12, increased fiber diameters were similar in implanted collagen-based sponges with or without HA and FN. Increased birefringence retardation in sponges containing HA and FN was consistent with increased packing density of collagen fibers observed by scanning electron microscopy.
Our results suggest that HA and FN are effective in promoting fibroblast movement into a collagen sponge and deposition of collagen fibers during the early phases of wound healing. Use of a collagen-based sponge containing HA and FN may enhance collagen deposition in situations where healing is compromised as in the case of dermal ulcers
Cancellation of vorticity in steady-state non-isentropic flows of complex fluids
In steady-state non-isentropic flows of perfect fluids there is always
thermodynamic generation of vorticity when the difference between the product
of the temperature with the gradient of the entropy and the gradient of total
enthalpy is different from zero. We note that this property does not hold in
general for complex fluids for which the prominent influence of the material
substructure on the gross motion may cancel the thermodynamic vorticity. We
indicate the explicit condition for this cancellation (topological transition
from vortex sheet to shear flow) for general complex fluids described by
coarse-grained order parameters and extended forms of Ginzburg-Landau energies.
As a prominent sample case we treat first Korteweg's fluid, used commonly as a
model of capillary motion or phase transitions characterized by diffused
interfaces. Then we discuss general complex fluids. We show also that, when the
entropy and the total enthalpy are constant throughout the flow, vorticity may
be generated by the inhomogeneous character of the distribution of material
substructures, and indicate the explicit condition for such a generation. We
discuss also some aspects of unsteady motion and show that in two-dimensional
flows of incompressible perfect complex fluids the vorticity is in general not
conserved, due to a mechanism of transfer of energy between different levels.Comment: 12 page
- âŠ