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Brain atrophy and cortical thinning are typically observed in people with Alzheimer's disease (AD) and, to a lesser extent, in those with mild cognitive impairment. In asymptomatic middle‐aged apolipoprotein ε4 (ΑPOE4) carriers, who are at higher risk of future AD, study reports are discordant with limited evidence of brain structural differences between carriers and non‐carriers of the ε4 allele. Alternative imaging markers with higher sensitivity at the presymptomatic stage, ideally quantified using typically acquired structural MRI scans, would thus be of great benefit for the detection of early disease, disease monitoring and subject stratification. In the present cross‐sectional study, we investigated textural properties of T1‐weighted 3T MRI scans in relation to APOE4 genotype, age and sex. We pooled together data from the PREVENT‐Dementia and ALFA studies focused on midlife healthy populations with dementia risk factors (analysable cohort: 1585 participants; mean age 56.2 ± 7.4 years). Voxel‐based and texture (examined features: contrast, entropy, energy, homogeneity) based morphometry was used to identify areas of volumetric and textural differences between APOE4 carriers and non‐carriers. Textural maps were generated and were subsequently harmonised using voxel‐wise COMBAT. For all analyses, APOE4, sex, age and years of education were used as model predictors. Interactions between APOE4 and age were further examined. There were no group differences in regional brain volume or texture based on APOE4 carriership or when age × APOE4 interactions were examined. Older people tended to have a less homogeneous textural profile in grey and white matter and a more homogeneous profile in the ventricles. A more heterogeneous textural profile was observed for females in areas such as the ventricles, frontal and parietal lobes and for males in the brainstem, cerebellum, precuneus and cingulate. Overall, we have shown the absence of volumetric and textural differences between APOE4 carriers and non‐carriers at midlife and have established associations of textural features with ageing and sex. [ABSTRACT FROM AUTHOR]

Purpose: Arterial spin labeling (ASL) is a widely used contrast‐free MRI method for assessing cerebral blood flow (CBF). Despite the generally adopted ASL acquisition guidelines, there is still wide variability in ASL analysis. We explored this variability through the ISMRM‐OSIPI ASL‐MRI Challenge, aiming to establish best practices for more reproducible ASL analysis. Methods: Eight teams analyzed the challenge data, which included a high‐resolution T1‐weighted anatomical image and 10 pseudo‐continuous ASL datasets simulated using a digital reference object to generate ground‐truth CBF values in normal and pathological states. We compared the accuracy of CBF quantification from each team's analysis to the ground truth across all voxels and within predefined brain regions. Reproducibility of CBF across analysis pipelines was assessed using the intra‐class correlation coefficient (ICC), limits of agreement (LOA), and replicability of generating similar CBF estimates from different processing approaches. Results: Absolute errors in CBF estimates compared to ground‐truth synthetic data ranged from 18.36 to 48.12 mL/100 g/min. Realistic motion incorporated into three datasets produced the largest absolute error and variability between teams, with the least agreement (ICC and LOA) with ground‐truth results. Fifty percent of the submissions were replicated, and one produced three times larger CBF errors (46.59 mL/100 g/min) compared to submitted results. Conclusions: Variability in CBF measurements, influenced by differences in image processing, especially to compensate for motion, highlights the significance of standardizing ASL analysis workflows. We provide a recommendation for ASL processing based on top‐performing approaches as a step toward ASL standardization. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Entorhinal cortex (EC) is the first cortical region to exhibit neurodegeneration in Alzheimer's disease (AD), associated with EC grid cell dysfunction. Given the role of grid cells in path integration (PI)–based spatial behaviors, we predicted that PI impairment would represent the first behavioral change in adults at risk of AD. METHODS: We compared immersive virtual reality (VR) PI ability to other cognitive domains in 100 asymptomatic midlife adults stratified by hereditary and physiological AD risk factors. In some participants, behavioral data were compared to 7T magnetic resonance imaging (MRI) measures of brain structure and function. RESULTS: Midlife PI impairments predicted both hereditary and physiological AD risk, with no corresponding multi‐risk impairment in episodic memory or other spatial behaviors. Impairments associated with altered functional MRI signal in the posterior‐medial EC. DISCUSSION: Altered PI may represent the transition point from at‐risk state to disease manifestation in AD, prior to impairment in other cognitive domains. [ABSTRACT FROM AUTHOR]

Prevalence estimations for Autism Spectrum Disorder have been increasing over the past few years with rates now reported to be at 1:68. Interventions that are based on Applied Behaviour Analysis are significantly related to best outcomes and are widely considered 'treatment as usual' in North America. In Europe, this is not the case, instead a rather ill-defined 'eclectic' approach is widely promoted and in this paper we discuss some of the roots of this gulf between Europe and North America and correct some of the misconceptions that prevail about Applied Behaviour Analysis in Europe.

Objectives: Intravenous fluid (IV) therapy is an important component of care for many hospital patients, especially in perioperative and acute care settings. However, errors in fluid composition and dosing can be life-threatening. To achieve competent professional performance, i.e., accurate and fluent, it is vitally important that medical students receive effective training in IV fluid therapy. Methods: In this study, we explored how Precision Teaching (PT), a behaviour analytic teaching method, can enhance outcomes of usual medical education techniques. A total of 178 third-year medical students participated in the study during the IV fluid therapy training week. All students completed a multiple-choice test pre- and post-training. In addition to standard IV fluid therapy teaching, the experimental intervention group (n=83 students) used SAFMEDS (Say All Fast MinuteEvery Day Shuffled) cards approximately 3-5 times per day for 5 days. The other 95 students (control group) received teaching as usual, but did not undergo the additional training. Results: Results show that the SAFMEDS boosted performance of the intervention group on the MCQ by 20 percentage points when compared to the control group. Fluency (accuracy and speed) of performance on SAFMED trials increased markedly during the intervention week and there was evidence that weaker students benefitted in particular. Conclusions: Implications for medical education are outlined.

Multidisciplinary practice has become an accepted approach in many education and social and health care fields. In fact, the right to a multidisciplinary assessment is enshrined in the United Nations Convention of the Rights for Persons with Disabilities (United Nations, 2007). In order to avert a "one size fits all" response to particularly heterogeneous diagnoses, such as autism spectrum disorders (ASD), the National Institute for Clinical Excellence (NICE) recommends multidisciplinary input. Yet, multidisciplinarity lacks empirical evidence of effectiveness, is fraught with conceptual difficulties and methodological incompatibilities, and therefore there is a danger of resorting to an ill-defined eclectic "hodgepodge" of interventions. Virtually all evidence-based interventions in autism and intellectual disabilities are behaviourally based. Not surprisingly, therefore, professionals trained in behaviour analysis to international standards are increasingly becoming key personnel in multidisciplinary teams. In fact, professionals from a range of disciplines seek training in behaviour analysis. In this article we brought together a multidisciplinary group of professionals from education, health, and social care, most of whom have a dual qualification in an allied health, social care, or educational profession, as well as in behaviour analysis. Together we look at the initial training in these professions and explore how behaviour analysis can offer a common and coherent conceptual framework for true multidisciplinarity, based on sound scientific knowledge about behaviour, without resort to reifying theories. We illustrate how this unifying approach can enhance evidence-based multidisciplinary practice so that "one size" will fit all.

Root herbivory caused by larvae of the forest cockchafer (Melolontha hippocastani) enhances the impact of drought on trees, particularly in oak forest rejuvenations. In Germany, geographically distant oak stands show differences in infestation strength by the forest cockchafer. While in Southwestern Germany this insect causes severe damage, oak forests in northern Germany are rarely infested. It is known that root-released volatile organic compounds (VOCs) are perceived by soil herbivores, thus guiding the larvae toward the host roots. In this work, we exposed seedlings of two distant oak provenances to forest cockchafer larvae and studied their population genetic properties, their root-based VOC chemotypes, their attraction for larvae and terpene synthase gene expression. Based on nuclear and chloroplast marker analysis, we found both oak populations to be genetically highly variable while showing typical patterns of migration from different refugial regions. However, no clear association between genetic constitution of the different provenances and the abundance of cockchafer populations on site was observed. In contrast to observations in the field, bioassays revealed a preference of the larvae for the northeastern oak provenance. The behavior of larvae was most likely related to root-released volatile terpenes and benzenoids since their composition and quantity differed between oak populations. We assume repellent effects of these compounds because the populations attractive to insects showed low abundance of these compounds. Five different oak terpene synthase (TPS) genes were identified at the genomic level which can be responsible for biosynthesis of the released terpenes. TPS gene expression patterns in response to larval feeding revealed geographic variation rather than genotypic variation. Our results support the assumption that root-released VOC are influencing the perception of roots by herbivores.

The current study involved an evaluation of the emergence of untrained verbal relations as a function of 3 different foreign-language teaching strategies. Two Spanish-speaking adults received foreign-language (English) tact training and native-to-foreign and foreign-to-native intraverbal training. Tact training and native-to-foreign intraverbal training resulted in the emergence of a greater number of untrained responses, and may thus be more efficient than foreign-to-native intraverbal training.