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A chemistry concept inventory (Chemical Concept Inventory 3.0/CCI 3.0) has been developed for assessing students learning and identifying the alternative conceptions that students may have in general chemistry. The conceptions in question are assumed to be mainly learned in school and to a less degree in student's daily life. The inventory presented here aims at functioning as a tool for adjusting teaching practices in chemistry and is mainly designed for assessing the learning outcome during university general chemistry courses. Used as a pre-test the inventory may also give information about student's starting point when entering university's first year chemistry courses.The inventory also aims at functioning as a tool for adjusting teaching practices in chemistry. It has been administered as a pre- and post-test in general chemistry courses at the Norwegian University of Science and Technology (NTNU), and evaluated using different statistical tests, focusing both on item analysis and the on the entire test. The results indicate that the concept inventory is a reliable and discriminating tool in the present context.

Proactive interference (PI) appears when familiar information interferes with newly acquired information and is a major cause of forgetting in working memory. It has been proposed that encoding of item–context associations might help mitigate familiarity-based PI. Here, we investigate whether encoding-related brain activation could predict subsequent level of PI at retrieval using trial-specific parametric modulation. Participants were scanned with event-related fMRI while performing a 2-back working memory task with embedded 3-back lures designed to induce PI. We found that the ability to control interference in working memory was modulated by level of activation in the left inferior frontal gyrus, left hippocampus, and bilateral caudate nucleus during encoding. These results provide insight to the processes underlying control of PI in working memory and suggest that encoding of temporal context details support subsequent interference control. [ABSTRACT FROM AUTHOR]

Semantic judgements involve the use of general knowledge about the world in specific situations. Such judgements are typically associated with activity in a number of brain regions that include the left inferior frontal gyrus (IFG). However, previous studies showed activity in brain regions associated with mentalizing, including the right temporoparietal junction (TPJ), in semantic judgements that involved social knowledge. The aim of the present study was to investigate if social and non‐social semantic judgements are dissociated using a combination of fMRI and repetitive TMS. To study this, we asked participants to estimate the percentage of exemplars in a given category that shared a specified attribute. Categories could be either social (i.e., stereotypes) or non‐social (i.e., object categories). As expected, fMRI results (n = 26) showed enhanced activity in the left IFG that was specific to non‐social semantic judgements. However, statistical evidence did not support that repetitive TMS stimulation (n = 19) to this brain region specifically disrupted non‐social semantic judgements. Also as expected, the right TPJ showed enhanced activity to social semantic judgements. However, statistical evidence did not support that repetitive TMS stimulation to this brain region specifically disrupted social semantic judgements. It is possible that the causal networks involved in social and non‐social semantic judgements may be more complex than expected. [ABSTRACT FROM AUTHOR]

Introduction: Gamma-aminobutyric acid (GABA) deficiency is suggested in depressive disorders, along with alterations in cortical excitability. However, whether these excitability changes are related to GABAA receptor availability is largely unknown. Our aim was to assess the correlation between these measures in depressed patients and healthy controls. Methods: Twenty-eight patients with a major depressive episode, measured before and after participating in a clinical trial with repetitive transcranial magnetic stimulation (TMS), and 15 controls underwent [11C]flumazenil positron emission tomography to assess GABAA receptor availability and paired pulse TMS (ppTMS) to evaluate cortical excitability. Both whole-brain voxel-wise GABAA receptor availability and mean values from left hand motor cortex and left paracentral lobule were correlated to the ppTMS outcomes: short-interval intracortical inhibition reflecting GABAA receptor activity, long-interval intracortical inhibition representing GABAB receptor activity, intracortical facilitation reflecting glutamate N-methyl-D-aspartate-receptor activity, as well as the resting motor threshold (rMT), considered a global measure of corticospinal excitability. Results: No significant differences in baseline GABAA receptor availability or cortical excitability were found between patients and controls. Additionally, no correlations were observed between baseline measurements of GABAA receptor availability and TMS outcomes. Changes in GABAA receptor availability in the hand motor cortex, between pre- and post-assessments, were inversely related to pre-post changes in hand rMT. Conclusion: We found that a change in GABAA receptor availability was inversely related to a change in rMT, suggesting a link between GABA deficiency and increased rMT previously observed in depressive episodes. The results highlight the complex mechanisms governing cortical excitability measures and offer new insight into their properties during the depressive state. [ABSTRACT FROM AUTHOR]

Recent advancements in studying long chains of unstable nuclei have revitalised interest in investigating the hyperfine anomaly. Hyperfine anomaly is particularly relevant for determining nuclear magnetic dipole moments using hyperfine structures where it limits the accuracy. This research paper focuses on the calculation of the differential Breit-Rosenthal effect for the 6 p 2 3 P 1 , 2 , 1 D 2 and 6 p 7 s 3 P 1 states in Pb, utilising the multi-configurational Dirac-Hartree-Fock code, GRASP2018. The findings show that the differential Breit-Rosenthal effect is typically less than 0.1 / f m 2 , which is often much smaller than the Bohr-Weisskopf effect. The differential Breit-Rosenthal effect for the 6 p 2 3 P 2 state is one order of magnitude smaller than the rest, which is why this state seems to be insensible to the hyperfine anomaly. [ABSTRACT FROM AUTHOR]

Background and Objectives We examined the extent to which externalizing behaviors such as violent and nonviolent criminal behavior, and substance use disorders (SUD) are associate with the onset of Alzheimer's disease (AD) and any dementia in prior generations. Research Design and Methods A nationwide cohort of 2,463,033 individuals born between 1973 and 1997 (index persons) were linked to their biological relatives (parents, grandparents, and uncles/aunts) using Swedish national registers. Cox regression models were used to examine the association between each measure of externalizing behaviors with AD and any dementia in each of the relative cohorts. Results Parents of index persons with externalizing behaviors had an increased risk for AD compared with parents of index persons without externalizing behaviors—nonviolent criminal behavior: Hazard Ratio (HR) = 1.16, 95% Confidence Intervals (CI) 1.10–1.22; violent criminal behavior: HR = 1.32 (95% CI: 1.19–1.45); SUD: HR = 1.28 (95% CI: 1.17, 1.40). The associations attenuated with decreasing familial relatedness. Relatives of individuals with externalizing behaviors compared with relatives of individuals without, showed an increased risk of having both early-onset and late-onset AD but the strength of the associations was higher for early-onset AD than for late-onset AD. A similar pattern of results was observed for the association with any dementia. Discussion and Implications Externalizing behaviors are associated with AD and any dementia in prior generations. The associations were stronger for parents in comparison with grandparents and uncles/aunts, suggesting shared familial risks between conditions. This warrants further studies examining common genetic and family-wide environmental factors that may contribute to identifying common underlying mechanisms to the development of externalizing behaviors, AD, and any dementia. [ABSTRACT FROM AUTHOR]

Background: Platelet-derived growth factor receptor beta (PDGFRβ) is a receptor overexpressed on activated hepatic stellate cells (aHSCs). Positron emission tomography (PET) imaging of PDGFRβ could potentially allow the quantification of fibrogenesis in fibrotic livers. This study aims to evaluate a fluorine-18 radiolabeled Affibody molecule ([18F]TZ-Z09591) as a PET tracer for imaging liver fibrogenesis. Results: In vitro specificity studies demonstrated that the trans-Cyclooctenes (TCO) conjugated Z09591 Affibody molecule had a picomolar affinity for human PDGFRβ. Biodistribution performed on healthy rats showed rapid clearance of [18F]TZ-Z09591 through the kidneys and low liver background uptake. Autoradiography (ARG) studies on fibrotic livers from mice or humans correlated with histopathology results. Ex vivo biodistribution and ARG revealed that [18F]TZ-Z09591 binding in the liver was increased in fibrotic livers (p = 0.02) and corresponded to binding in fibrotic scars. Conclusions: Our study highlights [18F]TZ-Z09591 as a specific tracer for fibrogenic cells in the fibrotic liver, thus offering the potential to assess fibrogenesis clearly. [ABSTRACT FROM AUTHOR]