Individual differences in susceptibility to inattentional blindness.

Inattentional blindness refers to the finding that people do not always see what appears in their gaze. Though inattentional blindness affects large percentages of people, it is unclear if there are individual differences in susceptibility. The present study addressed whether individual differences in attentional control, as reflected by variability in working memory capacity, modulate susceptibility to inattentional blindness. Participants watched a classic inattentional blindness video (Simons & Chabris, 1999) and were instructed to count passes among basketball players, wherein 58% noticed the unexpected: a person wearing a gorilla suit. When participants were accurate with their pass counts, individuals with higher working memory capacity were more likely to report seeing the gorilla (67%) than those with lesser working memory capacity (36%). These results suggest that variability in attentional control is a potential mechanism underlying the apparent modulation of inattentional blindness across individuals. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Effect of processing technique on the transport and mechanical properties of vapour grown carbon nanofibre/rubbery epoxy composites for electronic packaging applications

Vapour grown carbon nanofibre (VGCNF)/rubbery epoxy (RE) composites were produced, by either mechanical mixing, three-roll milling (RM) or combined ultrasonication/mechanical mixing. Incorporation of VGCNFs resulted in significant enhancements in the thermal and electrical conductivities of the material. Appropriate selection of processing technique and parameters can help to maximise the potential of VGCNF additions by improving their dispersion in the matrix. The composites produced by RM have superior transport properties compared with those produced by other techniques. The thermal conductivity of such composites at 40 wt.% VGCNFs reached 1.845 W/m K, a 10-fold increase compared to RE alone. The thermal conductivity data of VGCNF/RE composites best fits to the Hatta–Taya model. The lowest electrical percolation threshold is at 2 wt.%, obtained for composites produced by RM. The thermal conductivity of VGCNF/glassy epoxy (GE) composites at 12 wt.% is 10% lower than the corresponding RE composite but its electrical conductivity is 2 orders of magnitude higher than the corresponding RE composite. VGCNFs at 40 wt.% increase the compressive strength of rubbery epoxy by ～5× but the compressive modulus of 40 wt.% VGCNF/RE composite is 12 times lower than that of 12 wt.% VGCNF/GE composite, demonstrating highly compliant nature of RE composites.     

Carbon black/graphite nanoplatelet/rubbery epoxy hybrid composites for thermal interface applications

Hybrid composites were developed by dispersing carbon black (CB) nanoparticles and graphite nanoplatelets (GNPs) at 4–6 and 12–14 wt%, respectively, into rubbery epoxy resin. SEM analysis showed that CB particles improved the dispersion of GNPs in the hybrid composite. The thermal conductivity of 4 wt% CB/14 wt% GNP-15/rubbery epoxy hybrid composite, 0.81 W/m K, is ca. four times higher than that of rubbery epoxy. When silane-functionalised, the fillers reduced the viscosity of the hybrid dispersion and made the hybrid composite highly electrically insulating. Nevertheless, filler functionalisation decreased the composite’s thermal conductivity by only 16.6%. Compression testing showed that the hybrid fillers increased the compressive modulus and strength of rubbery epoxy by nearly two and three times, respectively. Overall, the hybrid composites with their thermal paste-type morphology, low viscosity, high compliance, improved thermal conductivity and, when fillers are functionalised, low electrical conductivity makes them promising materials as thermal interface adhesives.     

Test–retest reliability of the lifetime items on the Addiction Severity Index.

Longer interval (M =50.6, SD =13.1 days) test–retest reliability of the lifetime items on the Addiction Severity Index (ASI), a semistructured interview, was evaluated in 108 alcohol and/or cocaine dependent patients. They were administered the ASI at admission to an intensive outpatient rehabilitation treatment program and again after completion of this intervention and randomization into an aftercare study. Results demonstrated good to excellent reliability for participants' reports for most lifetime items in the medical, employment, drug, alcohol, and legal problem areas. Two of the ASI areas, family/social and psychiatric, had numerous items that did not achieve acceptable levels of reliability. Within these two problem areas, the more subjective and less operationally defined constructs had the poorest reliability. This study, in general, supports the longer interval test–retest reliability of the ASI lifetime items as well as the notion that alcohol and cocaine dependent patients under certain conditions can and do reliably report personal information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Discontinuous modelling of masonry bridges

 Computational modelling frameworks for masonry bridges range from highly simplified methods to complex nonlinear finite element or discrete elements. In majority of cases the macro level nonlinear finite element models¹ and homogenisation techniques are adopted. Attention has also been given to assessment methodologies (discrete element method, rigid block spring method, lattice modelling, discontinuous deformation analysis, combined discrete/finite elements), which deal more directly with the discontinuous nature of structural masonry in a simplified micro modeling manner. These methods model an inherently discontinuous medium, but are also applied to problems where the transition from a continuum to discontinuum is important. Principal computational issue is the treatment of large number of distinct interacting domains, where the contact conditions are continuously updated and enforced as the solution progresses. Modelling of masonry arches requires a consideration of deformable multi-bodies and their contact nonlinearity, which is here realised in the context of the discontinuous deformation analysis, based on an assumed deformation field within distinct domains of arbitrary shapes with a rigorous imposition of contact constraints. Dedicated to the memory of Prof. Mike Crisfield, for his cheerfulness and cooperation as a colleague and friend over many years.     

Children's Perceived Illness Uncertainty as a Moderator in the Parent-Child Distress Relation in Juvenile Rheumatic Diseases.

Objective: Examine children's perceived illness uncertainty as a potential moderator in the parent-distress/child-depressive-symptom relation in youths with juvenile rheumatic disease (JRD). Participants and Study Design: 50 youths between the ages of 9 and 17 and their parents completed self-report measures. Main Outcome Measures: Parents completed the Brief Symptom Inventory (L. R. Derogatis & N. Melisaratos, 1983); youths completed the Children's Depression Inventory (M. Kovacs, 1992) and the Children's Uncertainty in Illness Scale (L. L. Mullins & V. L. Hartman, 1995). Results: Children's perceived illness uncertainty moderated the parent-distress/child-depressive-symptom relation. Parent distress was associated with child depressive symptoms only under conditions of high child-perceived uncertainty; under conditions of low illness uncertainty, parent distress was unrelated to child depressive symptoms. Conclusions: Results highlight the role of children's cognitive appraisals in parent-child adjustment relations in JRD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance Study of Proactive Flow Handoff for Mobile Ad Hoc Networks

A Mobile Ad hoc Network (MANET) is a collection of wireless mobile computers forming a temporary network without any existing wire line infrastructure. Searching for feasible paths, or routing, is very challenging in mobile ad hoc networks because of frequent topology changes caused by users' mobility. Location information is required by some applications and can be used to facilitate routing implementation. In this paper, we propose a proactive flow handoff method based on nodes' location information. In summary, location information is utilised to reduce the control overhead in route discovery phase, to search quickly for a feasible path upon link breakage, and to hand off a flow to a stable path if the active one breaks based on predication. Keeping “always-on” end-to-end connectivity once a flow is established is the main advantage of this routing method. A thorough simulation study is performed to demonstrate the efficiency of this method. This research was supported by a grant from the Canadian Institute for Telecommunications Research under the NCE program of the Government of Canada. Kui Wu received his Ph.D in Computing Science from the University of Alberta, Canada, in 2002. He joined the Department of Computer Science at the University of Victoria, Canada in the same year and is currently an Assistant Professor there. His research interests include mobile and wireless networks, network performance evaluation, and network security. Janelle Harms received her Ph.D. in Computer Science from the University of Waterloo, Ontario, Canada working in the area of performance analysis of resource allocation mechanisms. She joined the Department of Computing Science at the University of Alberta in 1991 and is currently an Associate Professor there. Her research interests include performance aspects of network resource allocation, routing and design problems.     

Thalidomide. A surprising recovery

The epidemic of birth defects in Europe in the early 1960s attributed to thalidomide led to stringent and unprecedented drug safety requirements in many countries. No definitive mechanism of action has been determined for the biological activities associated with thalidomide. Food and Drug Administration and congressional concerns about the handling of clinical investigations of thalidomide led to sweeping new regulations for clinical trials. Thalidomide is currently being used clinically to treat such conditions as cachexia associated with HIV and cancer, mycobacterial disease, and autoimmune diseases.