Using event-related fMRI to examine sustained attention processes and effects of APOE ε4 in young adults

In this study we investigated effects of the APOE ε4 allele (which confers an enhanced risk of poorer cognitive ageing, and Alzheimer’s Disease) on sustained attention (vigilance) performance in young adults using the Rapid Visual Information Processing (RVIP) task and event-related fMRI. Previous fMRI work with this task has used block designs: this study is the first to image an extended (6-minute) RVIP task. Participants were 26 carriers of the APOE ε4 allele, and 26 non carriers (aged 18–28). Pupil diameter was measured throughout, as an index of cognitive effort. We compared activity to RVIP task hits to hits on a control task (with similar visual parameters and response requirements but no working memory load): this contrast showed activity in medial frontal, inferior and superior parietal, temporal and visual cortices, consistent with previous work, demonstrating that meaningful neural data can be extracted from the RVIP task over an extended interval and using an event-related design. Behavioural performance was not affected by genotype; however, a genotype by condition (experimental task/control task) interaction on pupil diameter suggested that ε4 carriers deployed more effort to the experimental compared to the control task. fMRI results showed a condition by genotype interaction in the right hippocampal formation: only ε4 carriers showed downregulation of this region to experimental task hits versus control task hits. Experimental task beta values were correlated against hit rate: parietal correlations were seen in ε4 carriers only, frontal correlations in non-carriers only. The data indicate that, in the absence of behavioural differences, young adult ε4 carriers already show a different linkage between functional brain activity and behaviour, as well as aberrant hippocampal recruitment patterns. This may have relevance for genotype differences in cognitive ageing trajectories

A Conceptual Framework for a Building Integrated Photovoltaics (BIPV) Educative-Communication Approach

Global interest in Building Integrated Photovoltaics (BIPV) has grown following forecasts of a compound annual growth rate of 18.7% and a total of 5.4 GW installed worldwide from 2013 to 2019. Although the BIPV technology has been in the public domain for the last three decades, its adoption has been hindered. Existing literature asserts that proper information and education at the proposal or early design stage is an important way of addressing adoption barriers. However, there is a lack of BIPV communication approaches for research, and market proposals that focus on clear information about its benefits. This has limited the adoption of BIPV.. Based on this, the present study aims to develop a conceptual framework for an educative-communication approach for presenting BIPV proposals to encourage its adoption. This is aimed at developing holistic research and market proposals which justify scholarly investigation and financial investment. Using a multiple case study investigation and Design Research Methodology (DRM) principles, the study developed an approach which combines core communication requirements, the pillars of sustainability and a hierarchical description of BIPV alongside its unique advantages. A two-step evaluation strategy involving an online pilot survey and a literature-based checklist, was used to validate the effectiveness of the developed approach. Our results show that understanding environmental and economic benefits was found to be significantly important to people who are likely adopters of BIPV (p < 0.05), making these benefits crucial drivers of adoption. Statistical significance was also found between those who do not know the benefits of using solar energy for electricity, and interest in knowing these benefits (p < 0.05). We thus conclude that proper communication of these benefits can safely be advanced as important facilitators of BIPV adoption. In general, this study elaborates the need and strategies for appropriate dissemination of innovative ideas to encourage and promote adoption of technological advancement for a sustainable global future

Anticholinesterase and Antioxidant Activities of Spilanthes filicaulis Whole Plant Extracts for the Management of Alzheimer’s Disease

Background: Spilanthes filicaulis is a tropical herb implicated as a memory enhancer in ethnomedicine. Objective: The study investigated acetyl/butyryl cholinesterase inhibitory and antioxidant activities of different extracts of S. filicaulis whole plant and correlated them to its phytochemical constituents. Methods: The powdered whole plant was successively extracted with n-hexane, ethyl acetate and methanol. Acetyl cholinesterase (AChE) and Butyryl cholinesterase (BuChE) inhibitory activity were evaluated by Ellman colorimetry assay. Antioxidant activity was tested using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing power and nitric oxide scavenging assays. Total phenolic, flavonoid and tannin were estimated using standard methods. Correlation was determined using Quest Graph™ Regression Calculator. Results: Various extracts exhibited concentration-dependent AChE and BuChE inhibitory activity with ethyl acetate extract being the highest with IC50 of 0.77 μg/mL and 0.92 μg/mL for AChE and BuChE respectively. The ethyl acetate extract also showed the highest reducing power when compared with the other extracts. The methanol extract had slightly higher phenolic and flavonoid content and showed the highest DPPH radical scavenging effect. DPPH scavenging, AChE and BuChE inhibition had high correlation with the total flavonoid content with R2 values of 1.00, 0.800 and 0.992 respectively while nitric oxide scavenging had high correlation with phenolics and tannins with R2 = 0.942 and 0.806 respectively. Conclusion: These results show that the extracts of the whole plant of S. filicaulis possess significant AChE/BuChE inhibitory and antioxidant properties, mostly due to its flavonoid content, suggesting the possible use of the plant in neurodegenerative diseases such as AD

Improved Process for Preparation of <i>tert</i>-Butanesulfinyl Ketimines of Hindered Ketones under Nitrogen Flow

An improved process for <i>tert</i>-butanesulfinyl ketimines formation using titanium­(IV) alkoxides is described. This new protocol gives better results especially for sterically hindered ketones compared to classical conditions where titanium­(IV) isopropoxide is found to be only moderately effective. We found that removal of isopropanol or ethanol from the reaction mixture either under a nitrogen flow or under vacuum dramatically increased reaction rate, extent of conversion, and yield of the reaction. This methodology has been exemplified on several substrates reported in the literature to be difficult

Using event-related fMRI to examine sustained attention processes and e?ects of APOE e4 in young adults

In this study we investigated effects of the APOE e4 allele (which confers an enhanced risk of poorer cognitive ageing, and Alzheimer’s Disease) on sustained attention (vigilance) performance in young adults using the Rapid Visual Information Processing (RVIP) task and event-related fMRI. Previous fMRI work with this task has used block designs: this study is the first to image an extended (6-minute) RVIP task. Participants were 26 carriers of the APOE e4 allele, and 26 non carriers (aged 18–28). Pupil diameter was measured throughout, as an index of cognitive effort. We compared activity to RVIP task hits to hits on a control task (with similar visual parameters and response requirements but no working memory load): this contrast showed activity in medial frontal, inferior and superior parietal, temporal and visual cortices, consistent with previous work, demonstrating that meaningful neural data can be extracted from the RVIP task over an extended interval and using an event-related design. Behavioural performance was not affected by genotype; however, a genotype by condition (experimental task/control task) interaction on pupil diameter suggested that e4 carriers deployed more effort to the experimental compared to the control task. fMRI results showed a condition by genotype interaction in the right hippocampal formation: only e4 carriers showed downregulation of this region to experimental task hits versus control task hits. Experimental task beta values were correlated against hit rate: parietal correlations were seen in e4 carriers only, frontal correlations in non-carriers only. The data indicate that, in the absence of behavioural differences, young adult e4 carriers already show a different linkage between functional brain activity and behaviour, as well as aberrant hippocampal recruitment patterns. This may have relevance for genotype differences in cognitive ageing trajectories

Modular Integration of Hydrogel Neural Interfaces

Thermal drawing has been recently leveraged to yield multifunctional, fiber-based neural probes at near kilometer length scales. Despite its promise, the widespread adoption of this approach has been impeded by (1) material compatibility requirements and (2) labor-intensive interfacing of functional features to external hardware. Furthermore, in multifunctional fibers, significant volume is occupied by passive polymer cladding that so far has only served structural or electrical insulation purposes. In this article, we report a rapid, robust, and modular approach to creating multifunctional fiber-based neural interfaces using a solvent evaporation or entrapment-driven (SEED) integration process. This process brings together electrical, optical, and microfluidic modalities all encased within a copolymer comprised of water-soluble poly(ethylene glycol) tethered to water-insoluble poly(urethane) (PU-PEG). We employ these devices for simultaneous optogenetics and electrophysiology and demonstrate that multifunctional neural probes can be used to deliver cellular cargo with high viability. Upon exposure to water, PU-PEG cladding spontaneously forms a hydrogel, which in addition to enabling integration of modalities, can harbor small molecules and nanomaterials that can be released into local tissue following implantation. We also synthesized a custom nanodroplet forming block polymer and demonstrated that embedding such materials within the hydrogel cladding of our probes enables delivery of hydrophobic small molecules in vitro and in vivo. Our approach widens the chemical toolbox and expands the capabilities of multifunctional neural interfaces

RVIP task performance.

<p>RVIP task performance.</p

Number of hits, by minute, for experimental and control tasks.

<p>F and p values for comparison between groups.</p