Personas revisited: Extending the use of personas to enhance participatory design

Personas are a well-established tool in interactive system development, largely used with designers and developers. They can also be included in work with potential and actual users, particularly in eliciting user needs and concerns. We present three case studies in which personas are part of the research with potential users of interactive systems. Blind participants in research on assistive technologies often spontaneously generated personas who would benefit more from the technology than they themselves would. This was a way of being able to discuss potential needs and concerns, without admitting to having them oneself. Older participants exploring the potential of indoor drones generated personas who were older than themselves and would need the system more. Finally, personas were created to aid discussions with forestry workers about fatigue and safety issues that they might not want to admit to having themselves. From these case studies we draw recommendations for how personas can be deployed in working with potential and actual users of interactive systems in a variety of ways

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Altered white matter microstructural organization in posttraumatic stress disorder across 3047 adults: results from the PGC-ENIGMA PTSD consortium

A growing number of studies have examined alterations in white matter organization in people with posttraumatic stress disorder (PTSD) using diffusion MRI (dMRI), but the results have been mixed which may be partially due to relatively small sample sizes among studies. Altered structural connectivity may be both a neurobiological vulnerability for, and a result of, PTSD. In an effort to find reliable effects, we present a multi-cohort analysis of dMRI metrics across 3047 individuals from 28 cohorts currently participating in the PGC-ENIGMA PTSD working group (a joint partnership between the Psychiatric Genomics Consortium and the Enhancing NeuroImaging Genetics through Meta-Analysis consortium). Comparing regional white matter metrics across the full brain in 1426 individuals with PTSD and 1621 controls (2174 males/873 females) between ages 18-83, 92% of whom were trauma-exposed, we report associations between PTSD and disrupted white matter organization measured by lower fractional anisotropy (FA) in the tapetum region of the corpus callosum (Cohen's d = -0.11, p = 0.0055). The tapetum connects the left and right hippocampus, for which structure and function have been consistently implicated in PTSD. Results were consistent even after accounting for the effects of multiple potentially confounding variables: childhood trauma exposure, comorbid depression, history of traumatic brain injury, current alcohol abuse or dependence, and current use of psychotropic medications. Our results show that PTSD may be associated with alterations in the broader hippocampal network.New methods for child psychiatric diagnosis and treatment outcome evaluatio

Neuroimaging-based classification of PTSD using data-driven computational approaches: a multisite big data study from the ENIGMA-PGC PTSD consortium

Background: Recent advances in data-driven computational approaches have been helpful in devising tools to objectively diagnose psychiatric disorders. However, current machine learning studies limited to small homogeneous samples, different methodologies, and different imaging collection protocols, limit the ability to directly compare and generalize their results. Here we aimed to classify individuals with PTSD versus controls and assess the generalizability using a large heterogeneous brain datasets from the ENIGMA-PGC PTSD Working group. Methods: We analyzed brain MRI data from 3,477 structural-MRI; 2,495 resting state-fMRI; and 1,952 diffusion-MRI. First, we identified the brain features that best distinguish individuals with PTSD from controls using traditional machine learning methods. Second, we assessed the utility of the denoising variational autoencoder (DVAE) and evaluated its classification performance. Third, we assessed the generalizability and reproducibility of both models using leave-one-site-out cross-validation procedure for each modality. Results: We found lower performance in classifying PTSD vs. controls with data from over 20 sites (60 % test AUC for s-MRI, 59 % for rs-fMRI and 56 % for D-MRI), as compared to other studies run on single-site data. The performance increased when classifying PTSD from HC without trauma history in each modality (75 % AUC). The classification performance remained intact when applying the DVAE framework, which reduced the number of features. Finally, we found that the DVAE framework achieved better generalization to unseen datasets compared with the traditional machine learning frameworks, albeit performance was slightly above chance. Conclusion: These results have the potential to provide a baseline classification performance for PTSD when using large scale neuroimaging datasets. Our findings show that the control group used can heavily affect classification performance. The DVAE framework provided better generalizability for the multi-site data. This may be more significant in clinical practice since the neuroimaging-based diagnostic DVAE classification models are much less site-specific, rendering them more generalizable.Stress-related psychiatric disorders across the life spa

Characterization of the polyphenolic composition of purple loosestrife (Lythrum salicaria)

Phenolic compounds of purple loosestrife (Lythrum salicaria L.) were analysed by the use of liquid chromatography - mass spectrometry (LC/MS) equipped with atmospheric pressure chemical ionisation (APCI) and electrospray ionisation (ESI). The presence of vitexin and orientin as well as their isomers, isovitexin and isoorientin, were confirmed using ion trap multiple stage LC/MS3 analysis. Several phenolic acids and tannins were also detected. Ellagitannins, vescalagin and pedunculagin, are reported from the plant for the first time

In vitro fermentation of browse species using goat rumen fluid in relation to browse polyphenol content and composition

The effect of browse species tannins (using polyethylene glycol, PEG 6000) on in vitro gas production (GP), methane (CH 4 ), ammonia (NH 3 ), volatile fatty acids (VFA) and in vitro organic matter digestibility (IVOMD) were studied. Approximately 0.5 g of air-dried A. etbaica, C. farinosa, C. tomentosa, D. angustifolia, D. cinerea, E. racemosa, M. angolensis, M. senegalensis, R. natalensis and S. singueana leaves were used as substrates in an automated in vitro system. Proanthocyanidin (PA) contents were quantified using the modified HCl-butanol method and the PA composition analysed by ultra performance liquid chromatography using a diode array detector coupled with electrospray ionization mass spectrometry (UPLC-DAD-ESI–MS/MS). Substrates were inoculated for 72 h in buffered rumen fluid (2:1, v/v), pooled from three goats fed a grass silage and concentrate diet, on three separate occasions. Each substrate was incubated in triplicate with or without inclusion of PEG 6000 and GP measured. During incubation, head space gas samples were taken at 0, 3, 6, 9, 12, 24, 30, 48, 54, and 72 h and analysed for CH 4 . Volatile fatty acids, NH 3 and IVOMD were determined after 72 h of incubation. Data from three runs were averaged for analysis. Addition of PEG increased (P < 0.0001) GP, CH 4 , NH 3 and total VFA indicating that PA were mainly involved in reducing methanogenesis but also digestibility. Prodelphinidins were found to be the major PA affecting fermentation. Also the contribution of quercetin, myricetin and kaempferol derivatives in CH 4 reduction were evident. Changes in the molar proportions of VFA with PEG addition indicated that PA affected fermentation pathways. The absence of PEG effect on IVOMD was due to artefacts from the tannin-PEG complexes interfering with the incubation residue measurement. Overall, the effect of tannin-containing browse on in vitro fermentation characteristics was mainly due to PA with the possible minor effects of other phenolic and non-phenolic compounds

Seasonal variation in the phenol content of Eugenia uniflora L. leaves Variação sazonal nos teores de fenóis de folhas de Eugenia uniflora L

Hydrolysable tannins, total phenols and flavonoids in Eugenia uniflora leaves were monthly analysed for one year. The results were correlated with climate conditions (rainfall, humidity, cloudiness and mean temperature) through chemometric methods. Principal component analysis revealed high levels of hydrolysable tannins in the rainy season, whereas flavonoids were mainly produced in the dry season. These facts suggest that climatic changes may be one of the factors affecting phenol levels in Eugenia uniflora.<br>Taninos hidrolisáveis, fenóis totais e flavonóides presentes em folhas de Eugenia uniflora foram quantificados mensalmente durante um ano. Os resultados foram correlacionados com as condições climáticas (pluviosidade, umidade, nebulosidade e temperatura média) através de métodos quimiométricos. Análise de componentes principais revelou a ocorrência de altos teores de taninos hidrolisáveis durante a estação de chuvas, enquanto os flavonóides foram produzidos principalmente na estação seca. Estes fatos sugerem que mudanças climáticas podem ser um dos fatores que afetam os níveis de fenóis em Eugenia uniflora