Toughening of a carbon-fibre composite using electrospun poly(Hydroxyether of Bisphenol A) nanofibrous membranes through inverse phase separation and inter-domain etherification

The interlaminar toughening of a carbon fibre reinforced composite by interleaving a thin layer (~20 microns) of poly(hydroxyether of bisphenol A) (phenoxy) nanofibres was explored in this work. Nanofibres, free of defect and averaging several hundred nanometres, were produced by electrospinning directly onto a pre-impregnated carbon fibre material (Toray G83C) at various concentrations between 0.5 wt % and 2 wt %. During curing at 150 °C, phenoxy diffuses through the epoxy resin to form a semi interpenetrating network with an inverse phase type of morphology where the epoxy became the co-continuous phase with a nodular morphology. This type of morphology improved the fracture toughness in mode I (opening failure) and mode II (in-plane shear failure) by up to 150% and 30%, respectively. Interlaminar shear stress test results showed that the interleaving did not negatively affect the effective in-plane strength of the composites. Furthermore, there was some evidence from DMTA and FT-IR analysis to suggest that inter-domain etherification between the residual epoxide groups with the pendant hydroxyl groups of the phenoxy occurred, also leading to an increase in glass transition temperature (~7.5 °C).

Genetic changes, intra- and inter-specific introgression in farmed Nile tilapia (Oreochromis niloticus) in Thailand

Fourteen microsatellite loci were used to examine genetic changes of four strains in Nile tilapia (Oreochromis niloticus) derived from genetically improved farmed tilapia (GIFT) and two strains derived from a local Chitralada strain of Nile tilapia in Thailand. Reference populations, including the ninth generation of GIFT strain, the original Chitralada strain, two conspecific reference populations from Ivory Coast and Uganda, and one population each of Oreochromis mossambicus and Oreochromis aureus, were also examined. Despite minor genetic changes, three of the four GIFT-derived populations retained their purity as GIFT while genetic variation did not decline. One of the GIFT-derived populations showed high levels of introgression from the Chitralada strain. Likewise, introgression from GIFT to the Chitralada-derived populations was seen. Inter-specific introgression from O. mossambicus was observed in the GIFT reference population and one of the Chitralada-derived strains. Introgression from O. aureus was detected in one of the GIFT-derived populations with a history of intensive inter-strain crossing. However, the introgression resulted in elevated genetic variation relative to the Chitralada original strains.

A framework for inter-organizational knowledge sharing : managerial influences

The purpose of this paper is to determine whether an existing organizational knowledge management framework could be utilized in an inter-organizational domain. We selected the threefold KM framework developed by Holsapple and Joshi (2000; 2002). This framework has been well tested and provides clearly defined elements to examine the influences on knowledge management and knowledge sharing in an organizational context. We report the results of testing the framework in three inter-organizational case studies and propose some adaptations to the managerial influences for inter-organizational analysis.

Inter-firm knowledge diffusion, market power, and welfare

We propose an infinite-horizon quantity-setting differential game with learning spillovers and organizational forgetting to analyze the optimal management decisions affecting the evolution of the stock of know-how, and, in turn, the dynamics of productive efficiency. Specifically, we study the long run impact of inter-firm knowledge diffusion on market power, i.e. the ability of a firm to raise the price above the marginal cost, and welfare. We consider two types of processes through which knowledge is acquired: (i) passive learning, or learning-by-doing, where managers do not actively invest in information and (ii) active learning, or learning-by-investing, where managers acquire new and additional information through specific investments in human capital. We show that: under (i), knowledge diffusion reduces market power; under (ii), knowledge diffusion reduces market power as long as learning spillovers are sufficiently important. From a welfare viewpoint, we also show that: under (i), knowledge diffusion is always welfare-enhancing; under (ii), weak spillovers are required in order for knowledge diffusion to be welfare-enhancing.

Carbon nanofibers with inter-bonded fibrous structure for supercapacitor application

In this study, we have improved carbon nanofiber interconnection by using two electrospinning methods: conventional electrospinning and side-by-side bicomponent electrospinning to produce polyvinylpyrrolidone (PVP)/polyacrylonitrile (PAN) blend nanofibers and PVP/PAN side-by-side bicomponent nanofibers respectively. Upon carbonization, the nanofibers showed inter-bonded morphologies. PVP here functioned to bind nanofibers during carbonization. The inter-boned fibrous morphology was highly affected by the PVP/PAN ratio and the electrospinning method. Carbon nanofibers prepared by the bicomponent electrospinning were found to have larger capacitances compared to those prepared by the conventional electrospinning. The influence of electrospinning method, PAN/PVP ratio on the crystallinity of carbon nanofibers, their surface morphology and capacitor performance were examined. The influence mechanism was elucidated as well.

Dissemination of therapist-assisted internet cognitive behaviour therapy : development and open pilot study of a workshop

There is considerable research suggesting that therapist-assisted Internet cognitive behaviour therapy (ICBT) is efficacious in the treatment of depression and anxiety. Given this research, there is a growing interest in training students in therapist-assisted ICBT in order to assist with the dissemination of this emerging modality into routine clinical practice. In this study, we developed, delivered, and evaluated a therapist-assisted ICBT workshop for clinical psychology graduate students (n = 20). The workshop provided both research evidence and practical information related to the delivery of therapist-assisted ICBT. The workshop also incorporated an experiential component with students working on and discussing responses to client e-mails. Before and after the workshop, we measured knowledge of therapist-assisted ICBT research and professional practice issues, as well as attitudes towards and confidence in delivering therapist-assisted ICBT. Statistically significant changes were observed in all areas. Eighty-five per cent of students are now offering therapist-assisted ICBT under supervision. We conclude by discussing future research directions related to disseminating therapist-assisted ICBT.

A therapist‐assisted internet‐based CBT intervention for posttraumatic stress disorder : preliminary results

Posttraumatic stress disorder (PTSD) is a debilitating mental health condition frequently associated with psychiatric comorbidity and diminished quality of life, and it typically follows a chronic, often lifelong, course. Previous research has shown that trauma‐related psychopathology (but not necessarily clinical PTSD) can be effectively treated via the Internet. This study is the first of its kind to report on the online treatment of patients with a Diagnostic and Statistical Manual of Mental Disorders (fourth edition) clinical diagnosis of PTSD with therapist support by e‐mail only. Preliminary findings are presented of an open trial involving a 10‐week Internet‐based therapist‐assisted cognitive behavioural treatment for PTSD (PTSD Online). Pre and posttreatment measures of PTSD and related symptomatology were compared for 16 participants with a variety of trauma experiences. Participants showed clinically significant reductions in PTSD severity and symptomatology, moderate tolerance of the program content, and high therapeutic alliance ratings. No significant change was found on measures of more general psychological symptoms. The results suggest that PTSD Online appears to be an effective and accessible clinical treatment for people with a confirmed PTSD diagnosis.