8,767 research outputs found
How does investor sentiment affect stock market crises? Evidence from panel data
We test the impact of investor sentiment on a panel of international stock markets. Specifically, we examine the influence of investor sentiment on the probability of stock market crises. We find that investor sentiment increases the probability of occurrence of stock market crises within a one-year horizon. The impact of investor sentiment on stock markets is more pronounced in countries that are culturally more prone to herd-like behavior and overreaction or in countries with low institutional involvement. Results also suggest that investors' sentiment is not a reliable predictor of stock market reversal pointsInvestor sentiment ; stock market crises ; reversal points
Collaboration and teamwork: immersion and presence in an online learning environment
In the world of OTIS, an online Internet School for occupational therapists, students from four European countries were encouraged to work collaboratively through problem-based learning by interacting with each other in a virtual semi-immersive environment. This paper describes, often in their own words, the experience of European occupational therapy students working together across national and cultural boundaries. Collaboration and teamwork were facilitated exclusively through an online environment, since the students never met each other physically during the OTIS pilot course. The aim of the paper is to explore the observations that here was little interaction between students from different tutorial groups and virtual teamwork developed in each of the cross-cultural tutorial groups. Synchronous data from the students was captured during tutorial sessions and peer-booked meetings and analysed using the qualitative constructs of âimmersionâ, âpresenceâ and âreflection in learningâ. The findings indicate that âimmersionâ was experienced only to a certain extent. However, both âpresenceâ and shared presence were found by the students, within their tutorial groups, to help collaboration and teamwork. Other evidence suggests that communities of interest were established. Further study is proposed to support group work in an online learning environment. It is possible to conclude that collaborative systems can be designed, which encourage students to build trust and teamwork in a cross cultural online learning environment.</p
Attractor Metadynamics in Adapting Neural Networks
Slow adaption processes, like synaptic and intrinsic plasticity, abound in
the brain and shape the landscape for the neural dynamics occurring on
substantially faster timescales. At any given time the network is characterized
by a set of internal parameters, which are adapting continuously, albeit
slowly. This set of parameters defines the number and the location of the
respective adiabatic attractors. The slow evolution of network parameters hence
induces an evolving attractor landscape, a process which we term attractor
metadynamics. We study the nature of the metadynamics of the attractor
landscape for several continuous-time autonomous model networks. We find both
first- and second-order changes in the location of adiabatic attractors and
argue that the study of the continuously evolving attractor landscape
constitutes a powerful tool for understanding the overall development of the
neural dynamics
Excitons in Electrostatic Traps
We consider in-plane electrostatic traps for indirect excitons in coupled
quantum wells, where the traps are formed by a laterally modulated gate
voltage. An intrinsic obstacle for exciton confinement in electrostatic traps
is an in-plane electric field that can lead to exciton dissociation. We propose
a design to suppress the in-plane electric field and, at the same time, to
effectively confine excitons in the electrostatic traps. We present
calculations for various classes of electrostatic traps and experimental proof
of principle for trapping of indirect excitons in electrostatic traps.Comment: 4 pages, 3 figure
Evaluation of role of concentration and molecular weight of oat β-glucan in determining effect of viscosity on plasma glucose and insulin following an oral glucose load
Data from clinical studies established that there was an inverse linear relationship between measures of postprandial blood glucose and insulin responses to an oral glucose load, consumed in a drink, and the logarithm of viscosity of the drink. These data have been re-analysed using concentration and molecular weight as the dependent variables. Molecular weight (M) of the β-glucans used was determined using high-performance size exclusion chromatography equipped with a triple detector system of right angle light scattering, viscometry and refractive index. A significant relationship between changes in peak blood glucose and a combination of logarithm of the concentration and logarithm of M was foun
Long-term evaluation of patients with free tissue transfer to the lower leg in terms of functional, socioeconomic, and esthetic aspects
A retrospective, quantitative, long-term evaluation of patients with a free flap transfer to the lower extremity was carried out with respect to functional, socioeconomic, and esthetic outcome. The study included 57 patients who were examined by questionnaire filled out by both an examiner and the patients themselves. Indications for the free flaps were acute trauma or osteomyelitis and unstable scars arising from a previous trauma to the lower leg. The flap success rate was 94.7%. The period between the operation and evaluation was at least 3years. A local, flap-specific functional impairment was found in 17 patients (30%) and a general impairment of the lower extremity in 56% of the subjects. With respect to the socioeconomic outcome more than two-thirds of the patients returned to their previous occupation with no restrictions; approximately 20% of subjects had to switch to a less strenuous job. Although from the viewpoint of the examiner the esthetic appearance was satisfactory in 44 free flaps (77%), the majority of the patients were conscious of pigmental, textural, or contour changes which produced a subjective esthetic compromise in 56% of cases. In conclusion, despite a considerably high rate of local functional impairment the majority of patients (89%) were satisfied and judged the application of a free flap as having been beneficial in preventing a loss in socioeconomic status. The high rate of esthetic problems demonstrates the importance of including esthetic considerations in designing the free flap, in particular with regard to (a) meticulously tailoring the flap, (b) aiming at a homogeneous skin surface, and (c) thoroughly shaping the affected lower extremit
Component importance measures for complex repairable system
In recent years, the system signature has been recognized as an important tool to quantify the reliability of systems consist of independent and identically distributed (iid) or exchangeable components with respect the random failure times. System signature separates the system structure from the component probabilistic failure distribution. However, when it is adopted to solve a complex system with more than one component type, it requires the computation of the probabilities of all possible different ordering statistics of each component failure lifetime distributions, which is often an intractable procedure
Direct neutron capture of 48Ca at kT = 52 keV
The neutron capture cross section of 48Ca was measured relative to the known
gold cross section at kT = 52 keV using the fast cyclic activation technique.
The experiment was performed at the Van-de-Graaff accelerator, Universitaet
Tuebingen. The new experimental result is in good agreement with a calculation
using the direct capture model. The 1/v behaviour of the capture cross section
at thermonuclear energies is confirmed, and the adopted reaction rate which is
based on several previous experimental investigations remains unchanged.Comment: 9 pages (uses Revtex), 2 postscript figures, accepted for publication
as Brief Report in Phys. Rev.
Spectra of Homologous Series of Monosubstituted Amides
Infrared spectra of the pure liquid and of dilute solution were observed for Nâmethyl, Nâethyl, Nâpropyl, and Nâbutyl acetamides and propionamides and of Nâdeuterated Nâbutylacetamide. Also infrared spectra of N15âbutylacetamide and Nâdeuterated N15âbutylacetamide and the Raman spectra of Nâbutylacetamide and Nâdeuterated Nâbutylacetamide were observed. In each series a band in the higher members was related to each band of the Nâmethyl compound on the basis of similarity in frequency, intensity, band width, and the influence of dilution. In Nâmethylacetamide and Nâbutylacetamide bands thus related were found to have also similar Raman activities and similar shifts on replacing the peptide hydrogen by deuterium. The extra bands could be related systematically to the extra CH2 groups. The implications of these results in protein spectroscopy and in the spectroscopic study of homologous series is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70627/2/JCPSA6-29-5-1097-1.pd
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