The Impact of Interface Quality on Trust in Web Retailers

Web retailing is expected to grow at aggressive rates in future years. One of the most important factors that is slowing down this growth is the lack of trust of potential customers. So, as transactions through the internet develop and mature, success will largely be dependent on gaining and0501ntaining this trust. It has been suggested that the quality of the user interface of the Web site is a determinant of the initial establishment of trust. In this article, we describe a study where 66 subjects were asked to perform some predefined book purchasing task in a series of sites with varying interface quality. We found a strong relationship between interface quality and trust. We also found some components of user interface quality to be more important than others and discuss the implications for Web site design. Le manque de confiance constitue une des barrières les plus importantes à l'adoption et au développement du commerce électronique. Centré sur le commerce électronique de détail, ce travail présente un modèle permettant d'analyser le développement de la confiance du consommateur en fonction des caractéristiques de ce dernier - sa propension - et de la perception qu'il a de certaines caractéristiques du commerçant, soit l'intégrité, l'habilité et la bienveillance de ce dernier. L'utilisabilité de l'interface graphique a été retenue comme étant le facteur-clé en ce qui concerne la perception de ces caractéristiques. Le rôle de chacune des dimensions composant l'utilisabilité a donc été étudié et mis en évidence relativement à la confiance développée par le consommateur.User interface, laboratory experiment, trust, usability, electronic retailing, web design, Interface utilisateur, expérimentation en laboratoire, confiance, b2c, commerce électronique (détail), design de site web

A universal constraint between charge and rotation rate for degenerate black holes surrounded by matter

We consider stationary, axially and equatorially symmetric systems consisting of a central rotating and charged degenerate black hole and surrounding matter. We show that $a^2+Q^2=M^2$ always holds provided that a continuous sequence of spacetimes can be identified, leading from the Kerr-Newman solution in electrovacuum to the solution in question. The quantity $a=J/M$ is the black hole's intrinsic angular momentum per unit mass, $Q$ its electric charge and $M$ the well known black hole mass parameter introduced by Christodoulou and Ruffini.Comment: 19 pages, 2 figures, replaced with published versio

Interoceptive conditioning with nicotine using extinction and re-extinction to assess stimulus similarity with bupropion

Bupropion is an atypical antidepressant that increases long-term quit rates of tobacco smokers. A better understanding of the relation between nicotine and this first-line medication may provide insight into improving treatment. For all experiments, rats first had nicotine (0.4 mg base/kg) and saline session intermixed; intermittent access to sucrose only occurred on nicotine session. Nicotine in this protocol comes to differentially control “anticipatory” dipper entries. To more closely examine the overlap in the interoceptive stimulus effects of nicotine and bupropion, we assessed whether subsequent prolonged and repeated non-reinforced (extinction) sessions with the bupropion stimulus could weaken responding to nicotine (i.e., transfer of extinction). We also examined whether retraining the discrimination after initial extinction and then conducting extinction again (i.e., re-extinction) with bupropion would affect responding. We found that bupropion (20 and 30 mg/kg) fully substituted for the nicotine stimulus in repeated 20-min extinction sessions. The extent of substitution in extinction did not necessarily predict performance in the transfer test (e.g., nicotine responding unchanged after extinction with 20 mg/kg bupropion). Generalization of extinction back to nicotine was not seen with 20 mg/kg bupropion even after increasing the number of extinction session from 6 to 24. Finally, there was evidence that learning in the initial extinction phase was retained in the re-extinction phase for nicotine and bupropion. These findings indicate that learning involving the nicotine stimuli are complex and that assessment approach for stimulus similarity changes conclusions regarding substitution by bupropion. Further research will be needed to identify whether such differences may be related to different facets of nicotine dependence and/or its treatment

Interoceptive conditioning with nicotine using extinction and re-extinction to assess stimulus similarity with bupropion

Bupropion is an atypical antidepressant that increases long-term quit rates of tobacco smokers. A better understanding of the relation between nicotine and this first-line medication may provide insight into improving treatment. For all experiments, rats first had nicotine (0.4 mg base/kg) and saline session intermixed; intermittent access to sucrose only occurred on nicotine session. Nicotine in this protocol comes to differentially control “anticipatory” dipper entries. To more closely examine the overlap in the interoceptive stimulus effects of nicotine and bupropion, we assessed whether subsequent prolonged and repeated non-reinforced (extinction) sessions with the bupropion stimulus could weaken responding to nicotine (i.e., transfer of extinction). We also examined whether retraining the discrimination after initial extinction and then conducting extinction again (i.e., re-extinction) with bupropion would affect responding. We found that bupropion (20 and 30 mg/kg) fully substituted for the nicotine stimulus in repeated 20-min extinction sessions. The extent of substitution in extinction did not necessarily predict performance in the transfer test (e.g., nicotine responding unchanged after extinction with 20 mg/kg bupropion). Generalization of extinction back to nicotine was not seen with 20 mg/kg bupropion even after increasing the number of extinction session from 6 to 24. Finally, there was evidence that learning in the initial extinction phase was retained in the re-extinction phase for nicotine and bupropion. These findings indicate that learning involving the nicotine stimuli are complex and that assessment approach for stimulus similarity changes conclusions regarding substitution by bupropion. Further research will be needed to identify whether such differences may be related to different facets of nicotine dependence and/or its treatment

Towards the grain boundary phonon scattering problem: an evidence for a low-temperature crossover

The problem of phonon scattering by grain boundaries is studied within the wedge disclination dipole (WDD) model. It is shown that a specific q-dependence of the phonon mean free path for biaxial WDD results in a low-temperature crossover of the thermal conductivity, $\kappa$. The obtained results allow to explain the experimentally observed deviation of $\kappa$ from a $T^3$ dependence below $0.1K$ in $LiF$ and $NaCl$.Comment: 4 pages, 2 figures, submitted to J.Phys.:Condens.Matte

Synthesis of Self-Immolative Monomers and Their Applications in Polymeric Materials

Self-immolative spacers are a unique class of molecules employed in a variety of applications, particularly in the biomedical field. Most commonly, they are molecules containing two reactive termini with a capping group at one terminus and a substrate of interest at the other. Upon removal of the capping group, the spacer undergoes an intramolecular reaction that results in its removal from the molecule and liberation of the substrate. These spacers have been extensively studied in monomeric form within prodrugs, as well as to form dendrimers that have been used for applications such as signal amplification, molecular logic gates and amplified drug release. Their use to form polymeric systems, however, remains largely unexplored and undeveloped. The work described in this thesis serves to expand this particular area of research, exploring the use of amine-based self-immolative spacers in the context of self-immolative polymers. Two new polymeric systems were developed using N,N-dimethylethylenediamine in conjunction with first 4-hydroxybenzyl alcohol and then 2-mercaptoethanol. In the first example, when a poly(ethylene glycol) end cap was used a block copolymer was formed that self-assembled in an aqueous environment and was capable of encapsulating a hydrophobic molecule and releasing it upon polymer degradation. The second polymeric system was the first fully aliphatic self-immolative polymer, and when a disulfide end cap was employed polymer degradation could be triggered by the addition of dithiothreitol. Following this work, a series of novel self-immolative spacers derived from 4-aminobutyric acid were developed in efforts to gain access to more rapidly cyclizing amine-based spacers. Carrying out modifications to the N and a positions, a series of spacers were developed with half-lives of cyclization ranging from 2 – 39 s. Lastly, these spacers were then combined with 4-hydroxybenzyl alcohol and 2’-hydroxyhydrocinnamic acid in efforts to develop novel 4-aminobutyric acid-based self-immolative polymers

Ramond-Ramond Central Charges in the Supersymmetry Algebra of the Superstring

The free action for the massless sector of the Type II superstring was recently constructed using closed RNS superstring field theory. The supersymmetry transformations of this action are shown to satisfy an N=2 D=10 SUSY algebra with Ramond-Ramond central charges.Comment: 10 pages harvmac te

Social isolation, loneliness & older people: The case of Iranians

The purpose of this paper is to study a group of elderly people in relation to social isolation and loneliness in older people and the effects it has on a person's well being. Social isolation and loneliness occurs in people of all ages but may be a particular problem in the older generation. The emphasis of this paper is placed upon social isolation and loneliness of a group of elderly Iranians living in metropolitan Sydney. The results showed that all the elderly participants of this study felt isolated and lonely in Australia. The causes had to do with their level of proficiency in the English language, loss and grief due to leaving their homeland and losing friends, political conflict in the Iranian community and the need for meaningful social support networks