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The purpose of this study is to investigate differences between women and men in chemistry, as reflected in their responses to a global gender gap survey. The survey was conducted in 2018; responses from 1,343 valid participants across the globe were collected and analyzed. The main results show that first, women were more likely to list their parents and themselves as important influences in their university studies than men. This result was consistent regardless of the Human Development Index (HDI, an index developed by the United Nations assessing the development of a country) and employment sectors. Also, men students reported more positive relationships and support from their advisors or supervisors than women. More women than men indicated that they had personally encountered sexual harassment at school or work. Also, in general, more men than women indicated that they had never experienced discrimination in the assessment or evaluation of their achievement across different HDI regions and in different employment sectors. Men reported having more research resources than women. More women than men indicated that their careers had influenced their decisions about their children, marriage, or long-term partnership across high and low HDI regions and employment sectors. Finally, women submitted fewer journal articles than men in the past five years, and this gender difference was also seen in respondents from both high and low HDI regions and working in industry. In contrast, by employment sector, the gender differences were relatively small.

Although research suggests a relationship among personal characteristics, behaviors, and performance, there has been limited examination of these influences in the context of intelligence tests using eye movement techniques. Thus, this study explored the roles of personal characteristics (i.e., visual/verbal cognitive styles, self-efficacy) and reading behaviors in the reasoning performance of Raven's Advanced Progressive Matrices test based on social cognitive perspectives using eye movement techniques, in order to provide more authentic information about individuals' actual behaviors. A total of 53 undergraduate and graduate students participated. Thirty participants were classified as visual style and the others were classified as verbal style learners. Regarding the role of cognitive styles in reading behaviors and reasoning performance, the results indicated a marginal difference in dispersion reading behavior between participants with visual and verbal cognitive style, and a significant relationship between visual style and dispersion reading behavior. However, no difference was found in performance between these two styles. As for the role of self-efficacy, the results showed that it was positively related to horizontal reading and APM-short performance. Mediation analyses revealed that self-efficacy not only directly impacted reasoning performance, but also had an indirect effect on performance through horizontal and tilted reading. On the other hand, cognitive style had no direct or indirect effect on reasoning performance. Moreover, the results showed that horizontal, vertical and tilted reading significantly predicted reasoning performance. The findings suggest that educators could enhance learners' self-efficacy through goal setting, feedback, and strategy instruction, which would help facilitate their learning behaviors and performance.

Abstract Background H2A.X is an H2A variant histone in eukaryotes, unique for its ability to respond to DNA damage, initiating the DNA repair pathway. H2A.X replacement within the histone octamer is mediated by the FAcilitates Chromatin Transactions (FACT) complex, a key chromatin remodeler. FACT is required for DEMETER (DME)-mediated DNA demethylation at certain loci in Arabidopsis thaliana female gametophytes during reproduction. Here, we sought to investigate whether H2A.X is involved in DME- and FACT-mediated DNA demethylation during reproduction. Results H2A.X is encoded by two genes in Arabidopsis genome, HTA3 and HTA5. We generated h2a.x double mutants, which displayed a normal growth profile, whereby flowering time, seed development, and root tip organization, S-phase progression and proliferation were all normal. However, h2a.x mutants were more sensitive to genotoxic stress, consistent with previous reports. H2A.X fused to Green Fluorescent Protein (GFP) under the H2A.X promoter was highly expressed especially in newly developing Arabidopsis tissues, including in male and female gametophytes, where DME is also expressed. We examined DNA methylation in h2a.x developing seeds and seedlings using whole genome bisulfite sequencing, and found that CG DNA methylation is decreased genome-wide in h2a.x mutant endosperm. Hypomethylation was most striking in transposon bodies, and occurred on both parental alleles in the developing endosperm, but not the embryo or seedling. h2a.x-mediated hypomethylated sites overlapped DME targets, but also included other loci, predominately located in heterochromatic transposons and intergenic DNA. Conclusions Our genome-wide methylation analyses suggest that H2A.X could function in preventing access of the DME demethylase to non-canonical sites. Overall, our data suggest that H2A.X is required to maintain DNA methylation homeostasis in the unique chromatin environment of the Arabidopsis endosperm.

Abstract Background To study whether oral presentation (OP) assessment could reflect the novice learners’ interpretation skills and reading behaviour on brain computed tomography (CT) reading. Methods Eighty fifth-year medical students were recruited, received a 2-hour interactive workshop on how to read brain CT, and were assigned to read two brain CT images before and after instruction. We evaluated their image reading behaviour in terms of overall OP post-test rating, the lesion identification, and competency in systematic image reading after instruction. Students’ reading behaviour in searching for the target lesions were recorded by the eye-tracking technique and were used to validate the accuracy of lesion reports. Statistical analyses, including lag sequential analysis (LSA), linear mixed models, and transition entropy (TE) were conducted to reveal temporal relations and spatial complexity of systematic image reading from the eye movement perspective. Results The overall OP ratings [pre-test vs. post-test: 0 vs. 1 in case 1, 0 vs. 1 in case 2, p

Abstract Background Over 2021, COVID-19 vaccination programs worldwide focused on raising population immunity through the primary COVID-19 vaccine series. In Singapore, two mRNA vaccines (BNT162b2 and mRNA-1273) and the inactivated vaccine CoronaVac are currently authorized under the National Vaccination Programme for use as the primary vaccination series. More than 90% of the Singapore population has received at least one dose of a COVID-19 vaccine as of December 2021. With the demonstration that vaccine effectiveness wanes in the months after vaccination, and the emergence of Omicron which evades host immunity from prior infection and/or vaccination, attention in many countries has shifted to how best to maintain immunity through booster vaccinations. Methods The objectives of this phase 3, randomized, subject-blinded, controlled clinical trial are to assess the safety and immunogenicity of heterologous boost COVID-19 vaccine regimens (intervention groups 1–4) compared with a homologous boost regimen (control arm) in up to 600 adult volunteers. As non-mRNA vaccine candidates may enter the study at different time points depending on vaccine availability and local regulatory approval, participants will be randomized at equal probability to the available intervention arms at the time of randomization. Eligible participants will have received two doses of a homologous mRNA vaccine series with BNT162b2 or mRNA-1273 at least 6 months prior to enrolment. Participants will be excluded if they have a history of confirmed SARS or SARS-CoV-2 infection, are immunocompromised, or are pregnant. Participants will be monitored for adverse events and serious adverse events by physical examinations, laboratory tests and self-reporting. Blood samples will be collected at serial time points [pre-vaccination/screening (day − 14 to day 0), day 7, day 28, day 180, day 360 post-vaccination] for assessment of antibody and cellular immune parameters. Primary endpoint is the level of anti-SARS-CoV-2 spike immunoglobulins at day 28 post-booster and will be measured against wildtype SARS-CoV-2 and variants of concern. Comprehensive immune profiling of the humoral and cellular immune response to vaccination will be performed. Discussion This study will provide necessary data to understand the quantity, quality, and persistence of the immune response to a homologous and heterologous third booster dose of COVID-19 vaccines. This is an important step in developing COVID-19 vaccination programs beyond the primary series. Trial registration ClinicalTrials.gov NCT05142319 . Registered on 2 Dec 2021.

This study utilized international, large-scale assessment data to compare science motivational beliefs of adolescents within and between countries and genders. The study focused on the beliefs about science of eighth graders, including their self-concept in science, the intrinsic value they ascribed to science, and their beliefs about the utility of the subject. The study data were derived from the Trends in International Mathematics and Science Study in 2019 (TIMSS) that was conducted in Taiwan, Australia, and the United States. To ensure the validity of mean cross-group comparisons, the measurement invariance (MI) of the constructs was first assessed. The multiple-group confirmatory factor analysis and latent factor mean comparisons were applied to the data. The results indicated that the MI of science motivational beliefs across the three countries attained only metric invariance, rendering a latent mean comparison implausible. However, the cross-gender MI within each country attained scalar invariance, supporting the comparison of means across genders. The science motivational beliefs of females were significantly lower than those of males, with the exception of beliefs of US students about their utility value. The findings of this study raise concerns about the validity of current international comparisons of science motivational beliefs of the students while supporting the use of TIMSS data to identify gender differences in science motivation within each country. The implications of MI across countries and genders are discussed, and the importance of establishing MI is highlighted. The findings affirm that gender disparities in science motivational beliefs can be compared using constructs with sound psychometric properties.

Toll mediates a robust and effective innate immune response across vertebrates and invertebrates. In Drosophila melanogaster, activation of Toll by systemic infection drives the accumulation of a rich repertoire of immune effectors in hemolymph, including the recently characterized Bomanins, as well as the classical antimicrobial peptides (AMPs). Here we report the functional characterization of a Toll-induced hemolymph protein encoded by the bombardier (CG18067) gene. Using the CRISPR/Cas9 system to generate a precise deletion of the bombardier transcriptional unit, we found that Bombardier is required for Toll-mediated defense against fungi and Gram-positive bacteria. Assaying cell-free hemolymph, we found that the Bomanin-dependent candidacidal activity is also dependent on Bombardier, but is independent of the antifungal AMPs Drosomycin and Metchnikowin. Using mass spectrometry, we demonstrated that deletion of bombardier results in the specific absence of short-form Bomanins from hemolymph. In addition, flies lacking Bombardier exhibited a defect in pathogen tolerance that we trace to an aberrant condition triggered by Toll activation. These results lead us to a model in which the presence of Bombardier in wild-type flies enables the proper folding, secretion, or intermolecular associations of short-form Bomanins, and the absence of Bombardier disrupts one or more of these steps, resulting in defects in both immune resistance and tolerance.

Fungal infections, widespread throughout the world, affect a broad range of life forms, including agriculturally relevant plants, humans, and insects. In defending against fungal infections, the fruit fly Drosophila melanogaster employs the Toll pathway to induce a large number of immune peptides. Some have been investigated, such as the antimicrobial peptides (AMPs) and Bomanins (Boms); many, however, remain uncharacterized. Here, we examine the role in innate immunity of two related peptides, Daisho1 and Daisho2 (formerly IM4 and IM14, respectively), found in hemolymph following Toll pathway activation. By generating a CRISPR/Cas9 knockout of both genes, Δdaisho, we find that the Daisho peptides are required for defense against a subset of filamentous fungi, including Fusarium oxysporum, but not other Toll-inducible pathogens, such as Enterococcus faecalis and Candida glabrata. Analysis of null alleles and transgenes revealed that the two daisho genes are each required for defense, although their functions partially overlap. Generating and assaying a genomic epitope-tagged Daisho2 construct, we detected interaction in vitro of Daisho2 peptide in hemolymph with the hyphae of F. oxysporum. Together, these results identify the Daisho peptides as a new class of innate immune effectors with humoral activity against a select set of filamentous fungi.

To construct CFA, MCFA, and maximum MCFA with LISREL v.8 and below, we provide iMCFA (integrated Multilevel Confirmatory Analysis) to examine the potential multilevel factorial structure in the complex survey data. Modeling multilevel structure for complex survey data is complicated because building a multilevel model is not an infallible statistical strategy unless the hypothesized model is close to the real data structure. Methodologists have suggested using different modeling techniques to investigate potential multilevel structure of survey data. Using iMCFA, researchers can visually set the between- and within-level factorial structure to fit MCFA, CFA and/or MAX MCFA models for complex survey data. iMCFA can then yield between- and within-level variance-covariance matrices, calculate intraclass correlations, perform the analyses and generate the outputs for respective models. The summary of the analytical outputs from LISREL is gathered and tabulated for further model comparison and interpretation. iMCFA also provides LISREL syntax of different models for researchers' future use. An empirical and a simulated multilevel dataset with complex and simple structures in the within or between level was used to illustrate the usability and the effectiveness of the iMCFA procedure on analyzing complex survey data. The analytic results of iMCFA using Muthen's limited information estimator were compared with those of Mplus using Full Information Maximum Likelihood regarding the effectiveness of different estimation methods.

Chronic systemic inflammation and repetitive damage of vascular endothelia by incompatible dialysis system are probable causes of cardiovascular disease in patients on dialysis. The present study aimed to assess in vitro biocompatibility and anti-inflammatory effect of hemodialysis fluid supplemented with rosmarinic acid (RA) using human umbilical vein endothelial cells (HUVEC). HUVECs (5×106 cells/mL) were pre-exposed to 1 μg/mL of lipopolysaccharides (LPS) and incubated with RA-supplemented hemodialysis fluid (HDF). Cytotoxicity was assessed qualitatively by morphologic assessment and quantitatively by MTT assay. Expressions of proinflammatory mediators were assessed using quantitative real-time PCR and production of NO was quantified. Phosphorylation of AKT and nuclear localization of nuclear factor kappa B (NF-κB) were examined using western blotting. Exposure of HUVECs to RA-supplemented HDF had no influence on morphology and viability. Inhibition of proinflammatory mediator production in HUVECs by RA supplementation to HDF was significant in a dose-dependent manner. Exposure to RA-supplemented HDF resulted in a decrease in nitric oxide synthase expression and reduction of NO production in LPS-stimulated HUVECs. RA supplementation of HDF suppressed Akt activation in LPS-stimulated HUVECs. In addition, the level of cellular IκB was increased in parallel to a reduced nuclear translocation of NF-κB in LPS-induced endothelial cells. Our results suggest that RA-supplemented HDF is biocompatible and significantly suppressed inflammation induced in endothelial cells. In this respect, the use of HDF supplemented with RA could alleviate inflammation and improve long-term treatment of patients with renal failure on dialysis. Further clinical studies are required to confirm the effects.

The issue of equality in the between-and within-level structures in Multilevel Confirmatory Factor Analysis (MCFA) models has been influential for obtaining unbiased parameter estimates and statistical inferences. A commonly seen condition is the inequality of factor loadings under equal level-varying structures. With mathematical investigation and Monte Carlo simulation, this study compared the robustness of five statistical models including two model-based (a true and a mis-specified models), one design-based, and two maximum models (two models where the full rank of variance-covariance matrix is estimated in between level and within level, respectively) in analyzing complex survey measurement data with level-varying factor loadings. The empirical data of 120 3rd graders' (from 40 classrooms) perceived Harter competence scale were modeled using MCFA and the parameter estimates were used as true parameters to perform the Monte Carlo simulation study. Results showed maximum models was robust to unequal factor loadings while the design-based and the miss-specified model-based approaches produced conflated results and spurious statistical inferences. We recommend the use of maximum models if researchers have limited information about the pattern of factor loadings and measurement structures. Measurement models are key components of Structural Equation Modeling (SEM); therefore, the findings can be generalized to multilevel SEM and CFA models. Mplus codes are provided for maximum models and other analytical models.

The present study investigated the following issues: (1) whether differences are evident in the eye movement measures of successful and unsuccessful problem-solvers; (2) what is the relationship between perceived difficulty and eye movement measures; and (3) whether eye movements in various AOIs differ when solving problems. Sixty-three 11th grade students solved five geometry problems about the properties of similar triangles. A digital drawing tablet and sensitive pressure pen were used to record the responses. The results indicated that unsuccessful solvers tended to have more fixation counts, run counts, and longer dwell time on the problem area, whereas successful solvers focused more on the calculation area. In addition, fixation counts, dwell time, and run counts in the diagram area were positively correlated with the perceived difficulty, suggesting that understanding similar triangles may require translation or mental rotation. We argue that three eye movement measures (i.e., fixation counts, dwell time, and run counts) are appropriate for use in examining problem solving given that they differentiate successful from unsuccessful solvers and correlate with perceived difficulty. Furthermore, the eye-tracking technique provides objective measures of students’ cognitive load for instructional designers.