203,284 research outputs found
Truth-telling and Trust in Sender-receiver Games with Intervention
No full textRecent experimental studies find excessive truth-telling in strategic information transmission games with conflictive preferences. In this paper, we show that this phenomenon is more pronounced in sender-receiver games where a truthful regulator randomly intervenes. We also establish that intervention significantly increases the excessive trust of receivers.Strategic information transmission, truth-telling, trust, sender-receiver game.
Probing Structure and Mobility of Proteins in the Amorphous State at Low Hydration
No full textThe characterization of proteins in the dry state has implications for the pharmaceutical industry, since it provides deeper understanding of the effect of lyophilisation on the stability and biological activity of bio-macromolecular drugs. We have performed structural and dynamical analyses on a series of lyophilised and hydrated bio-macromolecules with varying degrees of structural complexity by means of Molecular Dynamics (MD) simulations; the simulated dynamical results being compared to experimental findings obtained from neutron scattering.
Atomistic simulation of lyophilised proteins is still a challenge since the available force fields, and water molecule topology, used for the modelling have to be carefully correlated with experiment. Fortunately, the outputs from MD simulations, and the time and length scales probed, align directly with those accessed by neutron scattering. In particular, the method of Quasi-Elastic Neutron Scattering (QENS) can explore picosecond to nanosecond dynamics of macromolecular species and thus help validate the efficacy of the MD protocols applied.
Here we report on the simulated effect of temperature and hydration on the structural features of the proteins, focusing particularly on the predicted changes in secondary structure and radial distribution. We also present a comparison of the temperature dependence of the mean squared displacement parameter, obtained by analysing the MD trajectories, with those resulting from QENS measurements
Telling stories through space: The Mindstage Project
No full textMindstage is a real-time multi-user 3D virtual environment used to explore the relationships between a linear story and the virtual world in which it unfolds. The prototype uses as its narrative spine an illustrated lecture on film design by Christopher Hobbs. It provides a stage for interaction featuring a customized 3D environment based on this material, with the necessary actors and objects in it. The main design issues were mapping the linear talk onto the virtual space, and the implementation of various interactive features within it. We argue that a careful use of spatial design supports a degree of non-linear story-telling without compromising the core linear content
Hydration-induced dynamical changes in lyophilised and weakly hydrated apoferritin: insights from molecular dynamics simulation
No full textThe dynamics and functionality of proteins are significantly influenced by their interaction with water. For
lyophilised (i.e. h ≤ 0.05 where h = g of H2O/g of protein) and weakly hydrated systems (i.e. h ≤ 0.38) hydration
generally enhances protein mobility above the so-called ’dynamical transition’ temperature (Td > 220 K).
However, a water-induced mobility hindrance at low temperatures (T<175 K), has been reported in various
proteins of varying secondary structure; namely Green Fluorescent Protein (GFP), pig liver esterase, lysozyme,
Ribonuclease A (RNAse A) and apoferritin. By focussing on the dynamical behaviour of the apoferritin molecule,
this study proposes mechanisms driving these hydration-induced mobility changes, particularly the less
understood hindrance at low temperatures. Using atomistic Molecular Dynamics (MD) simulations of horse
spleen apoferritin in the lyophilised (h=0.05) and weakly hydrated (h=0.31) states, we report here the impact of
water on protein dynamics as a function of temperature. Through residue-specific mean squared displacement
(MSD), radial distribution function (RDF), solvent accessible surface area (SASA), local hydration degree and
hydrogen bonding analyses, we demonstrate that while water proximity directly correlates with mobility
enhancement at high temperatures, the hydration-induced mobility reduction observed at temperatures below
175 K is primarily propagated through the protein backbone
Polymer and water dynamics in Poly(vinyl alcohol)/Poly(methacrylate) networks. A molecular dynamics simulation and incoherent neutron scattering investigation
No full textChemically cross-linked polymer networks of poly(vinyl alcohol)/poly(methacrylate)
form monolitic hydrogels and microgels suitable for biomedical applications, such as
in situ tissue replacement and drug delivery. In this work, molecular dynamics (MD)
simulation and incoherent neutron scattering methods are used to study the local polymer
dynamics and the polymer induced modification of water properties in poly(vinyl
alcohol)/poly(methacrylate) hydrogels. This information is particularly relevant when the
diffusion of metabolites and drugs is a requirement for the polymer microgel functionality.
MD simulations of an atomic detailed model of the junction domain at the experimental
hydration degree were carried out at 283, 293 and 313 K. The polymer-water interaction,
the polymer connectivity and the water dynamics were investigated as a function of
temperature. Simulation results are compared with findings of elastic and quasi-elastic incoherent neutron scattering measurements, experimental approaches which sample the
same space-time window of MD simulations. This combined analysis shows a supercooled
water component and a temperature dependant increase of both hydrophilicity and mobility
in these amphiphilic polymer networks
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Children's moral evaluations of lie-telling and truth-telling in modesty contexts
No full textA thesis submitted in partial fulfillment of the requirements for the Degree of MASTER of ARTS in PSYCHOLOGY from Texas A&M University-Corpus Christi in Corpus Christi, Texas.Children’s moral evaluations of lie-telling and truth-telling, are influenced by culture (Lee, Cameron, Xu, Fu, & Board, 1997; Lee, Xu, Fu, Cameron, & Chen, 2001). Compared with Canadian children, eleven year olds Chinese children tend to rate modest lie-telling (lies about a good deed you have done) more positively than immodest truth-telling (admit a good deed you have done) (Lee et al., 1997; Lee et al., 2001). Additionally, older Chinese children (11 year olds) were more likely to rate modest lie-telling positively than younger children (7 and 9 year olds) (Lee et al., 2001). However, research suggested that specific social context could also influence people’s moral evaluations (Sweester, 1987). Previous research centered on this topic never considered a collaborative context in which children tend to show more modesty to their partner (Banerjee, 2000).
The present study bridges this gap by investigating American children’s moral evaluations of lie-telling and truth-telling involving a collaborative context. All the children were recruited from an elementary lab school located in South Texas where the student body is comprised of 60 percent Hispanic population.
We found that even American children tended to rate modest lie-telling more positively than immodest truth-telling in a pro-social situation when a collaborative context was involved. Also, there was a tendency for older (10-11 year olds) children to rate the modest lie-telling more positively than younger (7-8 year olds) children. Lastly, children spent more time in making a corresponding moral evaluation when lie-telling occurred in a pro-social context. This study suggests that the explanation of the modesty effect built on cultural factors might not be complete. Specific social contexts may also have an important effect.Psychology & SociologyCollege of Liberal Art
Thermo-physical investigation of low melting HFT and HSM containing calcium nitrate
No full textDespite its large interesting as component for low melting HTF and HSM, very few thermodynamics information is available regarding calcium nitrate and its mixtures. In this paper the binaries between Ca(NO3)2 and both NaNO3 and KNO3 are experimentally investigate by DSC and Neutron scattering. The results show that the solid phase of the binaries is composed by a solid solution of single nitrates. The DSC pattern and the eutectic point were modeled by the regular solution theory and the fitting parameters are reported. © 2019 Author(s)
Structural fluctuations in cross-linked matrices with narrow pore size distribution
No full textThe interplay between water and hydrophilic polymer matrices is object of study in many papers. Incoherent elastic, quasielastic neutron scattering and NMR low resolution relaxometry are among the most informative approaches for the understanding of the behaviour of water in confining media. A problem often occurring in these studies is the structural heterogeneity of systems such as hydrogels. As a consequence, all the investigated features are smeared in their values and the analysis of the related distributions is not an easy task to match. For this reasons, we present here an incoherent elastic neutron scattering study of hydrated polymer matrices with a narrow distribution of the pore size. The availability of such samples allows to study the relationship between the static and dynamic properties of the polymer network interacting with water. In this paper also, we propose a correlation of the parameters obtained by the analysis of incoherent elastic neutron scattering results by means of a simplified two well potential model with distinctive structural elements of the polymeric chains. © 2004 Elsevier B.V. All rights reserved
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