Building an atom from scratch using student participation on the lecture theatre stage

Background The concept of the atom is one of the first models and ideas presented to students in many chemistry courses. Indeed the introduction provides the foundation for numerous concepts such as reactivity and nuclear transformations. Commonly the concept of the atom is introduced by a visual representation and/or animation or video describing the various sub components (elementary particles) and their properties. Thus the introduction lends itself to various forms of blended learning and a variety of presentation formats addressing many types of student/teacher learning styles (Lockie, van Lanen and McGannon, 2013 & Salamonson et al., 2013 & Oskay et al., 2010). As well, as an introductory topic to chemistry, this is a critical time for many students and may even influence their future engagement, development and success in the course. We have adopted a simultaneous visual representation of the atom illustrating properties in combination with a demonstrative approach on the lecture theatre stage where we use student volunteers to represent fundamental particles. Aims Our aim was to develop, implement and refine a novel introduction to the atom illustrating its fundamental components as well as the concepts associated with these fundamental particles such as: • Electron energy levels • Size of atoms • Electron shielding/effective nuclear charge • Reactivity of atoms • Nuclear chemistry Design and methods We build up an atom from scratch starting with the capture of an electron by a proton using students to represent the fundamental particles on the lecture floor. We sequentially incorporate more students/particles to illustrate the various interactions which take place. Visual representations (Lecture slides) link the demonstration to atomic properties and highlight key aspects such as force distance relationships. Results Initial feedback from students was positive in relation to understanding the aspects listed in the aims. Conclusions A contemporary and novel approach to introducing the concept of the atom and its fundamental particles and properties which is suitable for students with varying subject knowledge has been incorporated into the first year chemistry course (currently in its fourth iteration and delivery for first year students). References Lockie, N. M., van Lanen, R. J., & McGannon, T. (2013). Educational implications of nursing students’ learning styles, success in chemistry, and supplemental instruction participation on national council licensure examination-registered nurses performance, Journal of Professional Nursing, 29: 49-58. Oskay, Ö. Ö., Erden, E., Akkoyunlu, B., & Yilmaz, A. (2010). Prospective chemistry teachers’ learning styles and learning preferences, Procedia Social and Behavioral Sciences, 2: 1362-1367. Salamonson, Y., Weaver, R., Chang, S., Koch, J., Bhathal, R., Khoo, C., & Wilson, I. (2013). Learning approaches as predictors of academic performance in first year health and science students, Nurse Education Today, 33: 729-733

A non-historical introduction for students to the periodic table

Background In many Universities there is a growing population of first year students who enter the system with very little prior knowledge of the subject. This, coupled with preconceived ideas of subject difficulty, necessitates that the introduction of key concepts is carried out in a non-threatening, engaging and simplistic manner. To this end, we have introduced a number of strategies to address this first contact situation with key concepts for first year chemistry students. One of the most important tools that a chemistry educator has at their disposal is the periodic table and this provides an important foundation for all aspects of chemistry. Indeed the periodic table is a fundamental classificatory system which underpins the whole realm of chemistry (Rouvray, 2004) and has even managed to transmute beyond the chemistry domain (e.g., Pugno, Marino and Carpinteri, 2005 & Brooks 2015). Traditionally this chemistry resource is introduced in a historical manner which identifies various aspects and builds up the table through time often highlighting key individuals. Numerous alternatives to this traditional approach also exist such as a context-based introductions (Demircioglu, 2009). We have adopted a novel non-historical approach for introducing the periodic table to our first year chemistry students beginning with the periodic table of super heroes (important historical components/aspects are introduced in other parts of the course and or in other chemistry courses). Aims Our aim was to develop, implement and refine a novel introduction to the periodic table for students which is based on key features of the periodic table including; Grouping using blocks and colour, Numbering, Use of Abbreviations, Combining individual objects/elements together, Transitioning across and down the Periodic table e.g., Size changes across and down the table. Design and methods We presented the key framework of the periodic table using a variety of illustrative ‘Tables’ with objects and components already familiar to the student. This included the periodic table of iPad apps, fruit and nuts, meat and super heroes. Each table is used to illustrate a key feature or features which is transferable to aspects relating to the periodic table of elements. Results Initial feedback from students was positive in relation to understanding the key aspects listed in the aims. Conclusions A contemporary and novel approach to introducing the periodic table, suitable for students of varying subject knowledge has been incorporated into the first year chemistry course (currently in its fourth iteration and delivery for first year students). References Brooks, C. (2015). The Periodic Table of the Electric Utiligy Landscape: A Series of Visual Tools for Enhanced Policy Analysis, The Electricity Journal, 28: 82-95. Demircioglu, H., Demircioglu, G., & Calik, M. (2009). Investigating the effectiveness of storylines embedded within a context-based approach: the case for the Periodic Table, Chemistry Education Research and Practice, 10: 241-249. Pugno, N., Marino, F., & Carpinteri, A. (2006). Towards a periodic table for the nanomechanical properties of the elements, International Journal of Solids and Structures, 43: 5647-5657. Rouvray, D. H. (2004). Elements in the history of the Periodic Table, Endeavour, 28: 69-74

Contrasting Micro/Nano Architecture on Termite Wings: Two Divergent Strategies for Optimising Success of Colonisation Flights

Many termite species typically fly during or shortly after rain periods. Local precipitation will ensure water will be present when establishing a new colony after the initial flight. Here we show how different species of termite utilise two distinct and contrasting strategies for optimising the success of the colonisation flight. Nasutitermes sp. and Microcerotermes sp. fly during rain periods and adopt hydrophobic structuring/‘technologies’ on their wings to contend with a moving canvas of droplets in daylight hours. Schedorhinotermes sp. fly after rain periods (typically at night) and thus do not come into contact with mobile droplets. These termites, in contrast, display hydrophilic structuring on their wings with a small scale roughness which is not dimensionally sufficient to introduce an increase in hydrophobicity. The lack of hydrophobicity allows the termite to be hydrophilicly captured at locations where water may be present in large quantities; sufficient for the initial colonization period. The high wettability of the termite cuticle (Schedorhinotermes sp.) indicates that the membrane has a high surface energy and thus will also have strong attractions with solid particles. To investigate this the termite wings were also interacted with both artificial and natural contaminants in the form of hydrophilic silicon beads of various sizes, 4 µm C18 beads and three differently structured pollens. These were compared to the superhydrophobic surface of the planthopper (Desudaba psittacus) and a native Si wafer surface. The termite cuticle demonstrated higher adhesive interactions with all particles in comparison to those measured on the plant hopper

Common Genetic Variation And Age at Onset Of Anorexia Nervosa

Background Genetics and biology may influence the age at onset of anorexia nervosa (AN). The aims of this study were to determine whether common genetic variation contributes to AN age at onset and to investigate the genetic associations between age at onset of AN and age at menarche. Methods A secondary analysis of the Psychiatric Genomics Consortium genome-wide association study (GWAS) of AN was performed which included 9,335 cases and 31,981 screened controls, all from European ancestries. We conducted GWASs of age at onset, early-onset AN (< 13 years), and typical-onset AN, and genetic correlation, genetic risk score, and Mendelian randomization analyses. Results Two loci were genome-wide significant in the typical-onset AN GWAS. Heritability estimates (SNP-h2) were 0.01-0.04 for age at onset, 0.16-0.25 for early-onset AN, and 0.17-0.25 for typical-onset AN. Early- and typical-onset AN showed distinct genetic correlation patterns with putative risk factors for AN. Specifically, early-onset AN was significantly genetically correlated with younger age at menarche, and typical-onset AN was significantly negatively genetically correlated with anthropometric traits. Genetic risk scores for age at onset and early-onset AN estimated from independent GWASs significantly predicted age at onset. Mendelian randomization analysis suggested a causal link between younger age at menarche and early-onset AN. Conclusions Our results provide evidence consistent with a common variant genetic basis for age at onset and implicate biological pathways regulating menarche and reproduction.Peer reviewe

Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders

Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyper-activity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.Peer reviewe

Shared genetic risk between eating disorder- and substance-use-related phenotypes:Evidence from genome-wide association studies

First published: 16 February 202

Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors

Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe

Genetic Overlap Between Alzheimer’s Disease and Bipolar Disorder Implicates the MARK2 and VAC14 Genes

Background: Alzheimer's disease (AD) and bipolar disorder (BIP) are complex traits influenced by numerous common genetic variants, most of which remain to be detected. Clinical and epidemiological evidence suggest that AD and BIP are related. However, it is not established if this relation is of genetic origin. Here, we applied statistical methods based on the conditional false discovery rate (FDR) framework to detect genetic overlap between AD and BIP and utilized this overlap to increase the power to identify common genetic variants associated with either or both traits. Methods: We obtained genome wide association studies data from the International Genomics of Alzheimer's Project part 1 (17,008 AD cases and 37,154 controls) and the Psychiatric Genetic Consortium Bipolar Disorder Working Group (20,352 BIP cases and 31,358 controls). We used conditional QQ-plots to assess overlap in common genetic variants between AD and BIP. We exploited the genetic overlap to re-rank test-statistics for AD and BIP and improve detection of genetic variants using the conditional FDR framework. Results: Conditional QQ-plots demonstrated a polygenic overlap between AD and BIP. Using conditional FDR, we identified one novel genomic locus associated with AD, and nine novel loci associated with BIP. Further, we identified two novel loci jointly associated with AD and BIP implicating the MARK2 gene (lead SNP rs10792421, conjunctional FDR=0.030, same direction of effect) and the VAC14 gene (lead SNP rs11649476, conjunctional FDR=0.022, opposite direction of effect). Conclusions: We found polygenic overlap between AD and BIP and identified novel loci for each trait and two jointly associated loci. Further studies should examine if the shared loci implicating the MARK2 and VAC14 genes could explain parts of the shared and distinct features of AD and BIP

Bipolar multiplex families have an increased burden of common risk variants for psychiatric disorders.

Multiplex families with a high prevalence of a psychiatric disorder are often examined to identify rare genetic variants with large effect sizes. In the present study, we analysed whether the risk for bipolar disorder (BD) in BD multiplex families is influenced by common genetic variants. Furthermore, we investigated whether this risk is conferred mainly by BD-specific risk variants or by variants also associated with the susceptibility to schizophrenia or major depression. In total, 395 individuals from 33 Andalusian BD multiplex families (166 BD, 78 major depressive disorder, 151 unaffected) as well as 438 subjects from an independent, BD case/control cohort (161 unrelated BD, 277 unrelated controls) were analysed. Polygenic risk scores (PRS) for BD, schizophrenia (SCZ), and major depression were calculated and compared between the cohorts. Both the familial BD cases and unaffected family members had higher PRS for all three psychiatric disorders than the independent controls, with BD and SCZ being significant after correction for multiple testing, suggesting a high baseline risk for several psychiatric disorders in the families. Moreover, familial BD cases showed significantly higher BD PRS than unaffected family members and unrelated BD cases. A plausible hypothesis is that, in multiplex families with a general increase in risk for psychiatric disease, BD development is attributable to a high burden of common variants that confer a specific risk for BD. The present analyses demonstrated that common genetic risk variants for psychiatric disorders are likely to contribute to the high incidence of affective psychiatric disorders in the multiplex families. However, the PRS explained only part of the observed phenotypic variance, and rare variants might have also contributed to disease development