Genomic epidemiology of SARS-CoV-2 in a UK university identifies dynamics of transmission

AbstractUnderstanding SARS-CoV-2 transmission in higher education settings is important to limit spread between students, and into at-risk populations. In this study, we sequenced 482 SARS-CoV-2 isolates from the University of Cambridge from 5 October to 6 December 2020. We perform a detailed phylogenetic comparison with 972 isolates from the surrounding community, complemented with epidemiological and contact tracing data, to determine transmission dynamics. We observe limited viral introductions into the university; the majority of student cases were linked to a single genetic cluster, likely following social gatherings at a venue outside the university. We identify considerable onward transmission associated with student accommodation and courses; this was effectively contained using local infection control measures and following a national lockdown. Transmission clusters were largely segregated within the university or the community. Our study highlights key determinants of SARS-CoV-2 transmission and effective interventions in a higher education setting that will inform public health policy during pandemics.</jats:p

Effects of a demonstration laboratory on student learning

Abstract Laboratory and demonstration have long been used to supplement lecture in chemistry education. Current research indicates that students are better served by laboratories which exercise the higher-order cognitive skills, such as inquiry-based laboratories. However, the time and the resources available to perform these recommended types of laboratories are continually shrinking. Due to these factors, a demonstration-laboratory was designed to allow students to make observations through demonstration rather then through hands-on laboratory. For this study, the hands-on procedures of an inquiry style laboratory were replaced by an instructor demonstration of these same procedures. A significant difference was found between student conceptual understanding before and after the experiment, indicating that students performing the laboratory experiment and students viewing the demonstrationlaboratory had an increase in conceptual understanding. However, no significant difference was found between the conceptual understanding of the two groups after the experiment, indicating that students learn roughly the same from both methods and that the demonstration-laboratory at least does no harm to the students conceptually. Longterm effects on student understanding were not measured. Student opinions comparing the demonstration laboratory to a hands-on laboratory were also collected and analyzed

The use of video demonstrations and particulate animation in general chemistry

Different visualization techniques have been used for teaching chemistry concepts. Previous studies have shown that when molecular animations and video demonstrations are used, students seem to better correlate all three levels of representation: macroscopic, submicroscopic, and symbolic. This thinking process allows the students to improve their conceptual understanding and ability to create dynamic mental models. In this study, general chemistry students viewed three experiments involving dynamic fluid equilibrium in a graphic design, a video demonstration, and a molecular animation. The study investigated whether video demonstrations or particulate animations helped the students' conceptual understanding, and if the order of visualizations (video or animation first) produced any differences. Students showed improvement after each visualization. Surprisingly, there was significant improvement in responses between the first and second visualization. This work shows the importance of combining both types of visualizations, but it does not indicate a preference toward a specific order

The effect of viewing order of macroscopic and particulate visualizations on students particulate explanations

A prior study showed that students best make predictions about the outcome of opening a valve between two flasks containing a fluid or vacuum when they view both a demonstration video and a particulate animation, but the study showed no influence from the order in which these visualizations were used. The purpose of this current research was to study the effect of the order of visualization on students particulate-level explanations. For this study, first-year general chemistry students in a south-central university in the United States were asked to choose, or type in their own explanations, for three experiments involving diffusion-effusion. Student ability to focus on particulate explanations was investigated after viewing either a macroscopic demonstration or an animated particle view. Students were directed to a Web site where they received one of two randomly assigned treatments. One group of students was shown the particulate animation first, followed by the macroscopic demonstration. For the other group, the order was reversed. Student explanations were assessed after each view. Finally, both groups were shown a side-by-side view of the animation and demonstration and their explanation was assessed one final time. Results showed that the order of visualizations did make a difference, with the macroscopic view followed by the particle view yielding significantly more particulate explanations

Chronic Physiologic Effects of Stress Among Lesbian, Gay, and Bisexual Adults: Results From the National Health and Nutrition Examination Survey.

ObjectiveSocial disadvantage is associated with markers of physiological dysregulation, which is linked to disease trajectories. Chronic experiences with discrimination are thought to result in the accumulation of physiological "wear and tear" known as allostatic load (AL) among socially marginalized populations such as sexual minorities. Using a nationally representative US sample, we examined whether (1) people who self-identified as homosexual or bisexual display higher levels of AL than heterosexual individuals and (2) subgroups of sexual identity would further differ from each other as a consequence of distinct experiences of marginalization.MethodsWe use data from the 2001-2010 National Health and Nutrition Examination Survey. Employing multivariate regression methods with sex-specific analyses, we examined AL score differences among lesbian/gay (n = 211), bisexual (n = 307), homosexually experienced (n = 424), and exclusively heterosexual (n = 12,969) individuals, adjusting for possible confounding due to demographics, health indicators, and, among men, HIV infection status.ResultsResults indicate that elevated AL was more common in bisexual men compared with exclusively heterosexual men (adjusted β = 0.25, 95% confidence interval [CI] = 0.05 to 0.44), with significantly higher levels of glycosylated hemoglobin A1c (adjusted odd ratio = 3.51, 95% CI = 1.46-7.92) and systolic blood pressure (adjusted odd ratio = 2.07, 95% CI = 1.02 to 4.18). Gay-identified men evidenced significantly lower AL (adjusted β = -0.22, 95% CI = -0.41 to -0.04). No significant differences in AL were observed among women.ConclusionsThese findings indicate that physiological dysregulation is more common in bisexual males compared with all other men. The results are discussed with regard to differences in health outcomes between individuals with different sexual orientations

Importance of Academic Legacy on Student Success in First- and Second-Semester General Chemistry

This investigation sought to elucidate the influence of students' academic legacy on their prior knowledge and course outcomes providing crucial insights for educators who teach general chemistry. This six-semester analysis involved 6,914 students enrolled in classes across nine Texas universities. Explored were personal circumstances associated with students' successes and failures that influenced performance in on- and off-sequence, first- and second-semester general chemistry (Chem 1 and Chem 2). Students' academic legacy based on their categorization as first generation (neither grandparent nor parent/guardian with a 4-year bachelor's degree), second generation (at least one grandparent or parent/guardian with a bachelor's degree), or third generation (at least one grandparent and at least one parent/guardian hold a bachelor's degree) was investigated. Of the students in the dataset 33.8% (n = 2,340) self-identified as Hispanic. Results for Hispanic and non-Hispanic students indicated that first-generation students struggled more with Chem 1 and Chem 2 than students in the other two legacy groups. As students' academic legacy extended, they were more apt to succeed in general chemistry. Second- and third-generation students demonstrated stronger prior high-school chemistry backgrounds and were enrolled in more advanced mathematics courses. As expected, students with stronger academic backgrounds in chemistry and mathematics scored higher on the diagnostic MUST (Math-Up Skills Test), had greater self-efficacy relative to their preparation to succeed, and reported fewer paid work hours. First-generation students on the average entered with lower diagnostic MUST scores, felt less prepared to succeed, and disclosed a greater need to be employed

MUST-Know Pilot—Math Preparation Study from Texas

Since 2007, the reported SAT (reading + math) scores for the state of Texas have steadily fallen from a high of 999 to an all-time low of 944. Solving this problem requires a multifaceted approach. For our part as instructors of a known gateway course, general chemistry, we chose to focus on the most fundamental crosscutting topic in STEM: arithmetic. Hence, the MUST Know (Mathematics: Underlying Skills and Thinking) study was conceived and implemented. General chemistry is widely considered a gateway course because students\u27 success in general chemistry provides entry into several STEM and some non-STEM careers. Failure to succeed in general chemistry has been linked to students\u27 mathematics fluency that other researchers have attributed to poor algebra skills. However, is it possible that this relationship should really be attributed to students\u27 lack of must-know arithmetic skills? In Fall 2016-Spring 2017, a team of 11 chemical educators investigated the relationships between solving simple arithmetic problems and course grades for 2,127 students (60.3% female) enrolled in general chemistry I and II at six post-secondary institutions (3, large public research universities; 2 Hispanic Serving Institutions; and 1, 4-year private university) from varied geographic locations in the heart of the state of Texas overlaying 32,000 square miles. The arithmetic concepts evaluated for this study are introduced to most Texas students starting at the 4th-grade level. The selected concepts include multiplication, division, fractions, scientific notation, exponential notation, logarithms, square roots and balancing chemical equations. Results support that students, without the aid of a calculator, succeeded at the 40%-correct level (Chem I) and 60%-correct level (Chem II). Students\u27 algebra skills might be a better predictor of overall success, but the initiator of the problem we posit starts with lack of automaticity and fluency with basic arithmetic skills. Correlations between final course grades and mathematics fluency ranged from 0.2-0.5 with the Hispanic-serving classes being among the weakest correlations and the research universities exhibiting the strongest. Building a strong profile of a successful general chemistry student is beginning to form from this continuing investigation. Future plans include implementation of High-Impact Practices (HIPs) to increase numeracy followed by dissemination of outcomes and expansion of the study to include other needed success-producing skills like logical thinking, spatial ability, and quantitative reasoning ability

Is the STEM Gender Gap Closing?

The Networking for Science Advancement (NSA) team's institutions consist of nine universities located in one large southwestern US state. This study evaluated students enrolled from Spring 2017 to Fall 2019 in firstand second-semester general chemistry. Over 90% of the students (n = 6,694) have been exposed to a secondary school isomorphic curriculum. The population studied, Chem I (n = 4,619) and Chem II (n = 2,075), met entry-level criteria and are therefore expected to succeed (i.e., earn grades of A, B or C). This study's focus is to disaggregate data based on binary gender (M/F) in hopes of revealing patterns that might remain hidden when studying an undivided population. In Chem I, the female population was 59.6% and increased to 64.5% for Chem II. The 15- min., diagnostic Math-Up Skills Test’s (MUST) scores identified about half of all students who were unsuccessful (grades of D and F). Results from the study support that males enter Chem I and II with better automaticity skills (what can be done without using a calculator) than females. However, females outperformed males on course averages in Chem I but not Chem II. Our data provide supporting evidence that the gender gap may be closing