PVDF membranes containing alkyl and perfluoroalkyl-functionalized graphene nanosheets for improved membrane distillation

Polyvinylidene fluoride (PVDF) membranes containing hydrophobic graphene nanofillers were prepared and tested for membrane distillation applications. The nanofillers were obtained by a two-step process: 1st) chemical grafting of hydrophobic molecules, either octylamine (OA) or perfluoroctylamine (PFOA), to graphene oxide (GO) nanosheets, and 2nd) chemical reduction of functionalized GO (rGO) to remove unreacted oxygen-containing functional groups. This resulted in OA-functionalized reduced GO (OA-rGO) and PFOA-functionalized rGO (PFOA-rGO). The addition of these nanomaterials to PVDF membranes prepared by the phase inversion process led to an increase in the membrane contact angle, and therefore higher hydrophobicity, as well as an increase in the membrane porosity. When comparing both nanofillers, OA-rGO and PFOA-rGO, the latter was more efficient in achieving higher contact angles due to the presence of fluorine atoms, whereas OA-rGO led to a greater enhancement in membrane porosity as compared to PFOA-rGO. MMMs containing 0.7 wt% nanofiller loadings of OA-rGO and PFOA-rGO achieved the highest water fluxes of 9.1 and 8.8 L m−2 h−1, respectively and salt rejection above 99.9%, which was monitored for at least 162 h of operation for the former. In comparison with pure PVDF (flux of 5 L m−2 h−1), the addition of OA-rGO and PFOA-rGO nanofillers results in a flux increment of 82% and 76%, respectively

Neural bases of Theory of Mind in children with autism spectrum disorders and children with conduct problems and callous-unemotional traits

Individuals with autism spectrum disorders (ASD) have difficulty understanding other minds (Theory of Mind; ToM), with atypical processing evident at both behavioural and neural levels. Individuals with conduct problems and high levels of callous-unemotional (CU) traits (CP/HCU) exhibit reduced responsiveness to others' emotions and difficulties interacting with others, but nonetheless perform normally in experimental tests of ToM. The present study aimed to examine the neural underpinnings of ToM in children (aged 10-16) with ASD (N = 16), CP/HCU (N = 16) and typically developing (TD) controls (N = 16) using a non-verbal cartoon vignette task. Whilst individuals with ASD were predicted to show reduced fMRI responses across regions involved in ToM processing, CP/HCU individuals were predicted to show no differences compared with TD controls. The analyses indicated that neural responses did not differ between TD and CP/HCU groups during ToM. TD and CP/HCU children exhibited significantly greater medial prefrontal cortex responses during ToM than did the ASD group. Within the ASD group, responses in medial prefrontal cortex and right temporoparietal junction (TPJ) correlated with symptom severity as measured by the Autism Diagnostic Observation Schedule (ADOS). Findings suggest that although both ASD and CP/HCU are characterized by social difficulties, only children with ASD display atypical neural processing associated with ToM

A technology toolkit to support accessibility of formative e-assessment for disabled students

This paper illustrates how problems with accessibility and ease of use of electronic formative assessment tools can be overcome by the judicious use of assistive technologies and presentation modes to enhance teaching and learning for disabled students and those with specific learning difficulties such as dyslexia. Where formative assessments are used to enhance teaching and learning to meet the needs of students, it is important to work in an inclusive environment to support diverse personal preferences and skills. Positive responses to e-assessment can only be achieved if a toolkit of support and guidance is available to both students and developers

An experiment in online AT open innovation

Objective. To initiate an experiment to see if an online tool can facilitate creation of new Assistive Technology (AT) through open innovation that engages the public (primarily end users and carers), prescribers, innovators and manufacturers. The final results and conclusions of the funded project which focus on AT relevant to access and use of Information Technology will be included in the poster. Main content. The REALISE project has created a prototype online platform. Open innovation is not widely employed in AT and so the approach in the platform assumes AT community members will explore the use of open innovation. The platform thus needs: information (definitions, guidance, and discussion of motivations of stakeholders), inclusive human computer interfacing, and open innovation process tools. Additionally, while good communication will be fundamentally important there are several other functional broad dimensions, ergonomic, language, educating and external connections/interaction. Solutions addressing these dimensions have to suit and excite the people expected to form the community otherwise user engagement is likely to be poor. Results. The platform website design and functioning is summarized, showing the open innovation framework employed (i.e. idea, incubator and project) and the use of an open community based solution as a market place for open source assistive technology engagement. The project's one year duration allowed for only one prototype to be developed and explored, so design decisions were made largely based on drawing parallels from other contexts and adhoc consultations with stakeholders. As in change management strategies, a bias to involve those who understood and were keen to try REALISE was employed, hoping that these people could then become advocates for open innovation in general and REALISE specifically. Networking to key external organisations was used both for promotion and engagement in the study. Conclusion. Designing any completely new service where a significant number of the potential users are not usually involved in the processes is challenging. The need for open innovation novices to gain access to support is seen as essential. Due to the project constraints a more participatory involvement of stakeholders and exploration of alternative strategies was not possible. Nevertheless new knowledge was gained about the use of open innovation in the field of AT

Imaging modes for direct electron detection in TEM with column parallel CCD

Electron imaging detectors have become the main limiting factor in transmission electron microscopy (TEM). A transition is now being made from indirect scintillator-coupled cameras to directly exposed detectors, which propose imaging modes that are novel in TEM. This work uses a dataset recoded with a directly exposed column parallel charge-coupled-device (CCD) to characterize modulation transfer and detective quantum efficiency of integrating, binary and counting imaging modes. Results presented here demonstrate that counting mode produces final images with largest contrast and highest efficiency because it takes into account the large lateral displacement of beam electrons in the detector. Counting imaging mode is recommended in TEM to take advantage from the higher sensitivity of directly exposed detectors. © 2009 Elsevier B.V. All rights reserved

PIM-1 Membranes Containing POSS - Graphene Oxide for CO2 Separation

PIM-1 mixed matrix membranes (MMMs) were fabricated with polyhedral oligomeric silsesquioxane (POSS) and graphene oxide (GO) functionalized with POSS (GO-POSS), and tested for CO2/N2 (single gas) and CO2/CH4 (1:1, v:v gas mixture). The CO2 permeability of the best performing fresh MMM (containing 0.05 wt% GO-POSS) was ∼ 12000 Barrer, which is 69% higher than that of the neat PIM-1 membrane, with about the same selectivity (CO2/CH4 selectivity ∼ 12 and CO2/N2 selectivity ∼ 20). In both cases, the gas separation data surpass the 2008 Robeson upper bound. In addition to the initial CO2 permeability enhancement, the use of GO-POSS is an efficient strategy to slow down physical aging. The MMM at a filler loading of 0.75 wt% showed less than half of the reduction in CO2 permeability than the neat PIM-1 membrane 160 days after preparation (26% for the MMM vs 58% for the purely polymeric one).S. Mohsenpour thanks the University of Manchester for funding his Ph.D. studies. P. Gorgojo acknowledges the Spanish Ministry of Economy and Competitiveness and the European Social Fund through the Ramon y Cajal programme (RYC2019-027060-I/AEI/10.13039/501100011033).Peer reviewe