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Science should provide students an accurate and contemporary education on genetic influence, particularly how it impacts trait variability and developmental norms. Stories involving familial, racial, and sexual differences routinely appear in the popular media and sales of over-the-counter genetic tests are mounting. Unfortunately, research suggests genetic curricula in secondary education and university courses have little impact on genetic literacy; instead they appear to amplify genetic essentialism. This position paper reports on genetic essentialism, the impact of three components of science education (teachers, students, curriculum), and critiques existing genetic lessons in two prevalent scientific disciplines, biology and psychology. Two entrenched 19th century genetic paradigms (e.g., Mendelian inheritance and behavioral genetics) are specifically examined. The paper closes with specific recommendations for improving students' genetic literacy including important contemporary genetic science (e.g., epigenetics) and instructional approaches (e.g., learning progression, refutational teaching).

Abstract: This paper focuses on the impact of elevated temperatures on the adsorptive and capillarity water retention mechanisms of unsaturated soils under constrained (constant volume) conditions. This topic is critical for simulating the thermo-hydraulic behavior of soils in hydrogeological or geotechnical applications, including climate change effects on near surface soils, energy piles or soil borehole thermal energy storage systems in unsaturated soil layers, and buffers for geological nuclear waste repositories. A nonisothermal soil water retention curve (SWRC) that separately considers the temperature-dependency of the key parameters governing adsorptive and capillarity water retention mechanisms and soil physical parameters (e.g., surface tension, contact angle, adsorption capacity, cation exchange capacity, mean cavitation suction, air entry value and equilibrium film thickness) was developed to provide insights into the impact of temperature on water retention over the full suction range. The nonisothermal SWRC was validated using experimental data on high plasticity clays, with a good prediction of temperature effects on adsorption and capillarity water retention mechanisms in constrained unsaturated soils.

Learning to read primary scientific literature (PSL) is an important part of developing scientific literacy skills. First-year students entering college often have little previous exposure to PSL and therefore face initial barriers in learning how to engage with PSL. Annotations have been shown to be a useful tool in undergraduate education and have potential for guiding students in developing higher-level reading strategies. In this study, we collected both qualitative and quantitative data to test the hypothesis of whether annotated PSL aids in the development of reading strategies for novice students learning to read PSL. Our qualitative results showed that annotations help students (i) break down PSL into manageable pieces, (ii) summarize the text, (iii) identify key information, and (iv) distinguish between different sections of PSL. Quantitatively, we saw no significant influence of annotations on the development of reading strategies for students learning to read PSL. Overall, our study provides a window into better understanding of specific strategies that students employ in reading PSL. Collectively, we suggest incorporating annotated PSL with some scaffolding social activities as an effective strategy to bring novice readers up the on-ramp of scientific literacy.

The 2019 coronavirus disease pandemic and distrust for popular media have highlighted the need for effective methods of direct communication of biomedical science to the public. It is presently unclear how well nonexperts can learn from primary scientific sources and what factors predict such learning in the general public. The present study examined three modalities for learning about biomedical science directly from study investigators: primary scientific articles, annotated primary scientific articles presented online with interactive learning features, and TEDTalks about scientific studies presented by a study investigator. Each modality presented the same study, "Sleep Drives Metabolite Clearance from the Adult Brain" (L. Xie, H. Kang, Q. Chen, Y. Liao, et al., Science 342:373--377, 2013, https://doi.org/10.1126/science.1241224). Knowledge about the study's scientific content was assessed before and after the randomly assigned learning modality using multiple-choice questions. Participants included a sample of college psychology students and a sample of community-dwelling older adults. Cognitive tests were used to assess individual differences in working memory, processing speed, science literacy, and semantic knowledge. Surveys were used to assess trust in science and scientists, attitudes toward science, and attitudes toward cognitive tasks. Results indicated that both younger and older adults can learn basic biomedical science from a primary source. Knowledge gains were observed in all three learning modalities with no evidence of age group differences. Notably, the largest learning gains for undergraduates and older adults were observed in the primary scientific article condition, followed by the TEDTalk, and the annotated paper. Baseline knowledge about the science study topic and adoption of "scientific attitudes" (e.g., open-mindedness) predicted learning across age groups and learning modalities. These findings suggest that science educators, communicators, and outreach professionals should consider methods of promoting science literacy in the general public through direct access to primary scientific sources.

In recent years, there has been a focus on improving geotechnical systems by implementing and constructing new deep foundation such as helical and expanded piles. This study examined the effects of parameters such as embedment depth, pile geometry, and axial loading direction on the load-displacement behaviour of these piles. To conduct the research, a database was compiled consisting of 80 axial loading test records for different piles. The embedment depth of the piles ranged from 2.4 to 36.8 m, and the diameter of helices or expanded parts ranged from 254 to 1500 mm. The ultimate load of the piles was determined using the 2.5% and 5% displacement ratio criteria and the Brinch-Hansen 80% method. Additionally, hyperbolic functions were fitted to the load-displacement curves, allowing for consistent estimation of the limit load and the initial tangent modulus. Analysis of the results from the database revealed that the dominant factors influencing the ultimate load, limit load, maximum measured load, initial stiffness, and load-displacement behaviour were the ratio of helices or expanded part diameter to shaft diameter, shaft and toe surface area, and load direction. Correlations derived from the database were validated using measurements from eight full-scale helical and expanded piles.

This study investigates the quasi-static bearing stress-settlement response of shallow foundations in monolithic tire derived aggregate (TDA) layers having a total thickness of 3 m using a large-scale container and loading system. Tests were performed on footings having a range of widths, embedment depths, shapes, and loading inclinations. In tests where tilting was restricted, a clear bearing capacity was not observed for settlements up to 1.2B, where B is the footing width, but in tests where tilting was permitted bearing capacity was observed between settlements of 0.2B to 0.7B. Surface settlements indicate a dragdown response of the TDA adjacent to the footing extending out to more than 3B from the footing center, while settlement plates beneath the footing indicate a zone of influence of induced settlements of 14% at a depth of 4B. While bearing capacity theories for frictional geomaterials provided a reasonable prediction of the bearing capacity of footings in TDA for most tests, the corresponding settlements may be excessive for engineering applications. Accordingly, a correlation was developed between the theoretical bearing capacity and bearing stress at a settlement of 0.1B. A test with sustained loading indicates slight creep settlements with some stress dependency with magnitudes consistent with past studies.

Discrete time models, one linear and one non-linear, are investigated, both with a herbivore species that consumes a basal food source species. Results are presented for coexistence of the species and to illustrate chaotic behaviour as parameters are varied in the non-linear model. The results indicate the benefit of fertilization in terms of the region of parameter space for which coexistence occurs. Possible extensions from these models for independent investigations are provided alongside classroom exercises.

Using the sawtooth map as the basis of a coupled map lattice enables simple analytic results to be obtained for the global Lyapunov spectra of a number of standard lattice networks. The results presented can be used to enrich a course on chaos or dynamical systems by providing tractable examples of higher dimensional maps and links to a number of standard results in matrices. A number of suggestions for classroom use are given.

Consultation evenings, also known as parent-teacher conferences, are important opportunities for teachers to strengthen their relationships with caregivers. Many teachers, however, are unprepared, having had few opportunities to build skills and participate in real consultations during teacher training. To provide student teachers with more practice opportunities, some teacher educators have begun supplementing students teachers' real-world consultations with simulations. Our goal in this study was to use findings on students' strengths and challenges in a simulated consultation to inform the design of future practice opportunities. Using factor analysis and descriptive statistics, we analysed 206 transcripts from 106 student teachers' simulations to uncover patterns in their consultations. We found that students were consistently good at sharing positive information about the pupil. Student teachers had more challenges finding the balance between facilitating a productive meeting and a collaborative one. Students also varied in how well they created and maintained a welcoming meeting environment when challenged by the caregiver or presented with a personal disclosure. Based on these findings, we propose designing targeted approximations of practice for consultations, in addition to more holistic ones, so that students can build skills in areas such as finding the balance between productivity and collaboration in a meeting.

Infection of airway epithelial cells with severe acute respiratory coronavirus 2 (SARS-CoV-2) can lead to severe respiratory tract damage and lung injury with hypoxia. It is challenging to sample the lower airways non-invasively and the capability to identify a highly representative specimen that can be collected in a non-invasive way would provide opportunities to investigate metabolomic consequences of COVID-19 disease. In the present study, we performed a targeted metabolomic approach using liquid chromatography coupled with high resolution chromatography (LC-MS) on exhaled breath condensate (EBC) collected from hospitalized COVID-19 patients (COVID+) and negative controls, both non-hospitalized and hospitalized for other reasons (COVID-). We were able to noninvasively identify and quantify inflammatory oxylipin shifts and dysregulation that may ultimately be used to monitor COVID-19 disease progression or severity and response to therapy. We also expected EBC-based biochemical oxylipin changes associated with COVID-19 host response to infection. The results indicated ten targeted oxylipins showing significative differences between SAR-CoV-2 infected EBC samples and negative control subjects. These compounds were prostaglandins A2 and D2, LXA4, 5-HETE, 12-HETE, 15-HETE, 5-HEPE, 9-HODE, 13-oxoODE and 19(20)-EpDPA, which are associated with specific pathways (i.e. P450, COX, 15-LOX) related to inflammatory and oxidative stress processes. Moreover, all these compounds were up-regulated by COVID+, meaning their concentrations were higher in subjects with SAR-CoV-2 infection. Given that many COVID-19 symptoms are inflammatory in nature, this is interesting insight into the pathophysiology of the disease. Breath monitoring of these and other EBC metabolites presents an interesting opportunity to monitor key indicators of disease progression and severity.

Abstract Background Fusarium head blight (FHB), caused by Fusarium graminearum, is a major disease of wheat in North America. FHB infection causes fusarium damaged kernels (FDKs), accumulation of deoxynivalenol (DON) in the grain, and a reduction in quality and grain yield. Inheritance of FHB resistance is complex and involves multiple genes. The objective of this research was to identify QTL associated with native FHB and DON resistance in a ‘D8006W’/’Superior’, soft white winter wheat population. Results Phenotyping was conducted in replicated FHB field disease nurseries across multiple environments and included assessments of morphological and FHB related traits. Parental lines had moderate FHB resistance, however, the population showed transgressive segregation. A 1913.2 cM linkage map for the population was developed with SNP markers from the wheat 90 K Infinium iSelect SNP array. QTL analysis detected major FHB resistance QTL on chromosomes 2D, 4B, 5A, and 7A across multiple environments, with resistance from both parents. Trait specific unique QTL were detected on chromosomes 1A (visual traits), 5D (FDK), 6B (FDK and DON), and 7D (DON). The plant height and days to anthesis QTL on chromosome 2D coincided with Ppd-D1 and were linked with FHB traits. The plant height QTL on chromosome 4B was also linked with FHB traits; however, the Rht-B1 locus did not segregate in the population. Conclusions This study identified several QTL, including on chromosome 2D linked with Ppd-D1, for FHB resistance in a native winter wheat germplasm.

Abstract Background Plasma growth differentiation factor 15 (GDF15) and N‐terminal proB‐type natriuretic peptide (NT‐proBNP) are cardiovascular biomarkers that associate with a range of diseases. Epigenetic scores (EpiScores) for GDF15 and NT-proBNP may provide new routes for risk stratification. Results In the Generation Scotland cohort (N ≥ 16,963), GDF15 levels were associated with incident dementia, ischaemic stroke and type 2 diabetes, whereas NT-proBNP levels were associated with incident ischaemic heart disease, ischaemic stroke and type 2 diabetes (all PFDR 95%) with levels of GDF15 and NT-proBNP, respectively. EpiScores for GDF15 and NT-proBNP were trained in a subset of the population. The GDF15 EpiScore replicated protein associations with incident dementia, type 2 diabetes and ischaemic stroke in the Generation Scotland test set (hazard ratios (HR) range 1.36–1.41, PFDR

Prolonged exposure to hyperbaric hyperoxia can lead to pulmonary oxygen toxicity (PO2tox). PO2tox is a mission limiting factor for special operations forces divers using closed-circuit rebreathing apparatus and a potential side effect for patients undergoing hyperbaric oxygen (HBO) treatment. In this study, we aim to determine if there is a specific breath profile of compounds in exhaled breath condensate (EBC) that is indicative of the early stages of pulmonary hyperoxic stress/PO2tox. Using a double-blind, randomized 'sham' controlled, cross-over design 14 U.S. Navy trained diver volunteers breathed two different gas mixtures at an ambient pressure of 2 ATA (33 fsw, 10 msw) for 6.5 h. One test gas consisted of 100% O2(HBO) and the other was a gas mixture containing 30.6% O2with the balance N2(Nitrox). The high O2stress dive (HBO) and low O2stress dive (Nitrox) were separated by at least seven days and were conducted dry and at rest inside a hyperbaric chamber. EBC samples were taken immediately before and after each dive and subsequently underwent a targeted and untargeted metabolomics analysis using liquid chromatography coupled to mass spectrometry (LC-MS). Following the HBO dive, 10 out of 14 subjects reported symptoms of the early stages of PO2tox and one subject terminated the dive early due to severe symptoms of PO2tox. No symptoms of PO2tox were reported following the nitrox dive. A partial least-squares discriminant analysis of the normalized (relative to pre-dive) untargeted data gave good classification abilities between the HBO and nitrox EBC with an AUC of 0.99 (±2%) and sensitivity and specificity of 0.93 (±10%) and 0.94 (±10%), respectively. The resulting classifications identified specific biomarkers that included human metabolites and lipids and their derivatives from different metabolic pathways that may explain metabolomic changes resulting from prolonged HBO exposure.

A growing body of literature shows that primary scientific literature (PSL) is a valuable and useful tool for science, technology, engineering, and math education. We currently have a relatively limited understanding of how skills relating to reading PSL progress through academic careers, i.e., the process by which expertise in reading PSL develops. In this study, we built on previous work showing clear differences in strategies that experts use to read PSL that are not often available to or documented with novice PSL readers. Using the five core concepts (5CCs) of biology, outlined in "Vision and Change in Undergraduate Biology," as a framework for student engagement with PSL, we investigated whether the 5CCs can be used to (i) increase student engagement with PSL, (ii) provide a context for PSL, and (iii) integrate student prior knowledge when reading PSL. Second, we investigated whether a 5CCs-based, semester-long intervention could shift student reading habits to be more expert-like. As no direct assessment for this exists, we instead measured student motivation for reading PSL, their Biology identity, and their perceived learning gains in science. We found that, through the use of the 5CCs as a framework for reading PSL, students were able to integrate previous knowledge and engaged with PSL constructively. Additionally, we saw positive shifts in student motivation for reading PSL, student Biology identity, and student self-reported learning gains in Biology. Taken together, the 5CCs, as a disciplinary framework, have great potential as a pedagogical tool for increasing student engagement with PSL in Biology classrooms.

Primary Scientific Literature (PSL) has been used in undergraduate classrooms as a way to engage students with the research process and to increase science literacy. Most curricula lack any formal training for undergraduates to critically read PSL even though most undergraduate science courses require students to engage with PSL at some level. In addition, there are limited studies exploring the process by which expertise in reading PSL develops in undergraduates. In this study, we adapted behaviors that expert and novice PSL readers exhibit into a quantitative assessment tool, the PSL Reading Strategies Assessment, to evaluate undergraduates' development of reading strategies when learning to read PSL. Factor analysis and reliability measures were implemented to determine the structure of our assessment tool. Our results show the PSL Reading Strategies Assessment is sensitive enough to measure differences among student populations, suggesting that it can be used as a diagnostic tool to guide instructors and researchers as they change curricula, implement new teaching strategies, and strive to develop students' science literacy. Moreover, our data show that developing expert-like reading strategies in students learning to read PSL is not easy. Simply reading a PDF does little to promote the development of reading strategies in students learning to read PSL.

Abstract Polygenic scores (PGSs) offer the ability to predict genetic risk for complex diseases across the life course; a key benefit over short-term prediction models. To produce risk estimates relevant to clinical and public health decision-making, it is important to account for varying effects due to age and sex. Here, we develop a novel framework to estimate country-, age-, and sex-specific estimates of cumulative incidence stratified by PGS for 18 high-burden diseases. We integrate PGS associations from seven studies in four countries (N = 1,197,129) with disease incidences from the Global Burden of Disease. PGS has a significant sex-specific effect for asthma, hip osteoarthritis, gout, coronary heart disease and type 2 diabetes (T2D), with all but T2D exhibiting a larger effect in men. PGS has a larger effect in younger individuals for 13 diseases, with effects decreasing linearly with age. We show for breast cancer that, relative to individuals in the bottom 20% of polygenic risk, the top 5% attain an absolute risk for screening eligibility 16.3 years earlier. Our framework increases the generalizability of results from biobank studies and the accuracy of absolute risk estimates by appropriately accounting for age- and sex-specific PGS effects. Our results highlight the potential of PGS as a screening tool which may assist in the early prevention of common diseases.

Abstract Background Exercise is known to improve health. However, it can be unpleasant, often inducing negative feelings, or ‘affect’. Cannabidiol (CBD), a non-intoxicating constituent of the cannabis plant, has been reported to enhance the subjective experience of exercise; specifically, in trained individuals performing fixed-intensity endurance activity. Here, we investigated the effects of CBD on subjective responses to exercise under more ecologically valid conditions; namely, in recreationally active individuals performing self-paced endurance activity. Methods A randomised, double-blind, placebo-controlled, crossover trial was conducted at Griffith University between July 17 and August 28, 2023. Griffith University students studying sports nutrition were invited to take part, with eligible volunteers ≥ 18 years of age and able to perform endurance exercise. Participants ingested placebo or 150 mg CBD in two soft-gel capsules 90 min before completing a self-paced 25-lap (10 km) run around an outdoor athletics track (400 m, synthetic). The primary outcomes were affective valence during exercise, assessed on completion of laps 6, 12, 18 and 24 using the ‘Feelings Scale’, and positive and negative affect, assessed at baseline, pre-run and post-run using the ‘Positive and Negative Affect Schedule’. Exercise enjoyment, motivation and self-efficacy, the core features of the ‘runner’s high’ (i.e., euphoria, pain, anxiety, sedation), perceived exertion and run time were also assessed. Results Fifty-two participants were randomised and 51 were included in the final sample (n = 22 female; 22 [21–25] years). Exercise induced negative affect (i.e., at the time of undertaking) and increased pain. CBD did not counteract either response. In fact, CBD had no significant effects on any of the outcomes measured. In contrast, exercise, once completed, increased positive affect, and decreased negative affect and anxiety. Conclusions CBD (150 mg, oral) does not appear to enhance the subjective experience of self-paced endurance exercise in recreationally active individuals. Nor, however, does it appear to compromise it. These findings suggest that CBD use is safe under exercise conditions and unlikely to impede physical activity participation. Our study also reaffirms the powerful mood-enhancing effects of exercise. Trial Registration Registered with the Australian New Zealand Clinical Trials Registry ( www.anzctr.org.au ) on May 31, 2023 (Trial ID: ACTRN12623000593639).

In high-level radioactive waste geological repositories, compacted bentonite undergoes coupled thermo-hydraulic processes due to heat released from a central waste canister and groundwater imbibition from the surrounding host rock. An understanding of these processes is essential for long-term simulations radionuclide migration and canister corrosion, which requires an understanding temperature effects on the coupled thermo-hydraulic properties governing these processes. In this study, a tank-scale radial infiltration test was used to investigate water imbibition processes in compacted bentonite under a central heater temperature of 200°C that simulates high thermal gradients in a repository. Interpretation of this test focuses on evaluation of the liquid water wetting front during hydration and the interpretation of the temperature-dependent transient soil water retention curve (SWRC), thermal conductivity function (TCF), and hydraulic conductivity function (HCF). The SWRC during imbibition follows a temperature-dependent wetting path. Temperature effects on the hydraulic conductivity of bentonite in saturated conditions had the greatest effect on the shape of the HCF, with minimal temperature effects at higher suctions. The transient thermal conductivity data matched well with a new TCF linked with the SWRC shape. Although the bentonite layer was restrained, local deformations during hydration may have affected the shapes of the TCF and HCF.

Here the Human Pangenome Reference Consortium presents a first draft of the human pangenome reference. The pangenome contains 47 phased, diploid assemblies from a cohort of genetically diverse individuals1. These assemblies cover more than 99% of the expected sequence in each genome and are more than 99% accurate at the structural and base pair levels. Based on alignments of the assemblies, we generate a draft pangenome that captures known variants and haplotypes and reveals new alleles at structurally complex loci. We also add 119 million base pairs of euchromatic polymorphic sequences and 1,115 gene duplications relative to the existing reference GRCh38. Roughly 90 million of the additional base pairs are derived from structural variation. Using our draft pangenome to analyse short-read data reduced small variant discovery errors by 34% and increased the number of structural variants detected per haplotype by 104% compared with GRCh38-based workflows, which enabled the typing of the vast majority of structural variant alleles per sample.

There has been tremendous progress in phased genome assembly production by combining long-read data with parental information or linked-read data. Nevertheless, a typical phased genome assembly generated by trio-hifiasm still generates more than 140 gaps. We perform a detailed analysis of gaps, assembly breaks, and misorientations from 182 haploid assemblies obtained from a diversity panel of 77 unique human samples. Although trio-based approaches using HiFi are the current gold standard, chromosome-wide phasing accuracy is comparable when using Strand-seq instead of parental data. Importantly, the majority of assembly gaps cluster near the largest and most identical repeats (including segmental duplications [35.4%], satellite DNA [22.3%], or regions enriched in GA/AT-rich DNA [27.4%]). Consequently, 1513 protein-coding genes overlap assembly gaps in at least one haplotype, and 231 are recurrently disrupted or missing from five or more haplotypes. Furthermore, we estimate that 6-7 Mbp of DNA are misorientated per haplotype irrespective of whether trio-free or trio-based approaches are used. Of these misorientations, 81% correspond to bona fide large inversion polymorphisms in the human species, most of which are flanked by large segmental duplications. We also identify large-scale alignment discontinuities consistent with 11.9 Mbp of deletions and 161.4 Mbp of insertions per haploid genome. Although 99% of this variation corresponds to satellite DNA, we identify 230 regions of euchromatic DNA with frequent expansions and contractions, nearly half of which overlap with 197 protein-coding genes. Such variable and incompletely assembled regions are important targets for future algorithmic development and pangenome representation.