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Oysters play an important role in coastal ecology and are a globally popular seafood source. However, their filter-feeding lifestyle enables coastal pathogens, toxins, and pollutants to accumulate in their tissues, potentially endangering human health. While pathogen concentrations in coastal waters are often linked to environmental conditions and runoff events, these do not always correlate with pathogen concentrations in oysters. Additional factors related to the microbial ecology of pathogenic bacteria and their relationship with oyster hosts likely play a role in accumulation but are poorly understood. In this study, we investigated whether microbial communities in water and oysters were linked to accumulation of Vibrio parahaemolyticus, Vibrio vulnificus, or fecal indicator bacteria. Site-specific environmental conditions significantly influenced microbial communities and potential pathogen concentrations in water. Oyster microbial communities, however, exhibited less variability in microbial community diversity and accumulation of target bacteria overall and were less impacted by environmental differences between sites. Instead, changes in specific microbial taxa in oyster and water samples, particularly in oyster digestive glands, were linked to elevated levels of potential pathogens. For example, increased levels of V. parahaemolyticus were associated with higher relative abundances of cyanobacteria, which could represent an environmental vector for Vibrio spp. transport, and with decreased relative abundance of Mycoplasma and other key members of the oyster digestive gland microbiota. These findings suggest that host and microbial factors, in addition to environmental variables, may influence pathogen accumulation in oysters. IMPORTANCE Bacteria in the marine environment cause thousands of human illnesses annually. Bivalves are a popular seafood source and are important in coastal ecology, but their ability to concentrate pathogens from the water can cause human illness, threatening seafood safety and security. To predict and prevent disease, it is critical to understand what causes pathogenic bacteria to accumulate in bivalves. In this study, we examined how environmental factors and host and water microbial communities were linked to potential human pathogen accumulation in oysters. Oyster microbial communities were more stable than water communities, and both contained the highest concentrations of Vibrio parahaemolyticus at sites with warmer temperatures and lower salinities. High oyster V. parahaemolyticus concentrations corresponded with abundant cyanobacteria, a potential vector for transmission, and a decrease in potentially beneficial oyster microbes. Our study suggests that poorly understood factors, including host and water microbiota, likely play a role in pathogen distribution and pathogen transmission.

Faculty have conducted many studies on the relationship between learning mode and student performance but few researchers have evaluated final grades, grade distribution, and pass rates in a sophomore introductory statistics course with a non-traditional student population who self-selected the learning mode from among different course sections. Accordingly, we examined 307 end-of-course grades from four different modes of instruction: (1) online; (2) videosynchronous learning classroom; (3) videosynchronous learning home; and (4) traditional classroom in an introductory statistics course. All data on grades, which included pass rate and grade distribution, were collected from the nine-week January 2019 term. All learning modes used the same text, syllabus, assignments, quizzes, and tests. In this study, learning mode was not significantly related to end-of-course score, final grade distribution, or pass rate. Future researchers should explore the impacts of gender, instructor quality, different term lengths, and the standardized use of textbooks and syllabi on student performance when exploring the impact of learning mode on grades, grade distribution, and pass rates.

Feedback best practices support timely, high-quality feedback with application opportunity. Multiple attempts on assessments support learning gains. A learning management system can be used to automatically provide feedback for application on a future assessment attempt. Current research has not thoroughly investigated the student impacts or opinions on this combined strategy. In this study, students took a second attempt 46% of the time, scoring an average of 10.1% higher on their second attempt. More than 60% of students who failed their first attempt completed a second attempt. Students perceived the feedback as useful in preparing for their second attempt. Future research should include investigations of why some students do not make a second quiz attempt and in what ways feedback is used (or not). This study demonstrates the effectiveness of this feedforward with multiple attempts strategy in multiple introductory science courses taught fully online.

BackgroundChildren may be at higher risk for swimming-associated illness following exposure to fecally-contaminated recreational waters. We analyzed a pooled data set of over 80,000 beachgoers from 13 beach sites across the United States to compare risks associated with the fecal indicator bacteria Enterococcus spp. (measured by colony forming units, CFU and quantitative polymerase chain reaction cell equivalents, qPCR CE) for different age groups across different exposures, sites and health endpoints.MethodsSites were categorized according to the predominant type of fecal contamination (human or non-human). Swimming exposures of varying intensity were considered according to degree of contact and time spent in the water. Health endpoints included gastrointestinal and respiratory symptoms and skin rashes. Logistic regression models were used to analyze the risk of illness as a function of fecal contamination in water as measured by Enterococcus spp. among the exposed groups. Non-swimmers (those who did not enter the water) were excluded from the models to reduce bias and facilitate comparison across groups.ResultsGastrointestinal symptoms were the most sensitive health endpoint and strongest associations were observed with Enterococcus qPCR CE at sites impacted by human fecal contamination. Under several exposure scenarios, associations between illness and Enterococcus spp. levels were significantly higher among children compared to adolescents and adults. Respiratory symptoms were also associated with Enterococcus spp. exposures among young children at sites affected by human fecal sources, although small sample sizes resulted in imprecise estimates for these associations.ConclusionUnder many exposure scenarios, children were at higher risk of illness associated with exposure to fecal contamination as measured by the indicator bacteria Enterococcus spp. The source of fecal contamination and the intensity of swimming exposure were also important factors affecting the association between Enterococcus spp. and swimming-associated illness.

Municipal wastewater provides an integrated sample of a diversity of human-associated microbes across a sewershed, including viruses. Wastewater-based epidemiology (WBE) is a promising strategy to detect pathogens and may serve as an early warning system for disease outbreaks. Notably, WBE has garnered substantial interest during the coronavirus disease 2019 (COVID-19) pandemic to track disease burden through analyses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA. Throughout the COVID-19 outbreak, tracking SARS-CoV-2 in wastewater has been an important tool for understanding the spread of the virus. Unlike traditional sequencing of SARS-CoV-2 isolated from clinical samples, which adds testing burden to the health care system, in this study, metatranscriptomics was used to sequence virus directly from wastewater. Here, we present a study in which we explored RNA viral diversity through sequencing 94 wastewater influent samples across seven wastewater treatment plants (WTPs), collected from August 2020 to January 2021, representing approximately 16 million people in Southern California. Enriched viral libraries identified a wide diversity of RNA viruses that differed between WTPs and over time, with detected viruses including coronaviruses, influenza A, and noroviruses. Furthermore, single-nucleotide variants (SNVs) of SARS-CoV-2 were identified in wastewater, and we measured proportions of overall virus and SNVs across several months. We detected several SNVs that are markers for clinically important SARS-CoV-2 variants along with SNVs of unknown function, prevalence, or epidemiological consequence. Our study shows the potential of WBE to detect viruses in wastewater and to track the diversity and spread of viral variants in urban and suburban locations, which may aid public health efforts to monitor disease outbreaks. IMPORTANCE Wastewater-based epidemiology (WBE) can detect pathogens across sewersheds, which represents the collective waste of human populations. As there is a wide diversity of RNA viruses in wastewater, monitoring the presence of these viruses is useful for public health, industry, and ecological studies. Specific to public health, WBE has proven valuable during the coronavirus disease 2019 (COVID-19) pandemic to track the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) without adding burden to health care systems. In this study, we used metatranscriptomics and reverse transcription-droplet digital PCR (RT-ddPCR) to assay RNA viruses across Southern California wastewater from August 2020 to January 2021, representing approximately 16 million people from Los Angeles, Orange, and San Diego counties. We found that SARS-CoV-2 quantification in wastewater correlates well with county-wide COVID-19 case data, and that we can detect SARS-CoV-2 single-nucleotide variants through sequencing. Likewise, wastewater treatment plants (WTPs) harbored different viromes, and we detected other human pathogens, such as noroviruses and adenoviruses, furthering our understanding of wastewater viral ecology.

Wastewater surveillance for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has garnered extensive public attention during the coronavirus disease pandemic as a proposed complement to existing disease surveillance systems. Over the past year, methods for detection and quantification of SARS-CoV-2 viral RNA in untreated sewage have advanced, and concentrations in wastewater have been shown to correlate with trends in reported cases. Despite the promise of wastewater surveillance, for these measurements to translate into useful public health tools, bridging the communication and knowledge gaps between researchers and public health responders is needed. We describe the key uses, barriers, and applicability of SARS-CoV-2 wastewater surveillance for supporting public health decisions and actions, including establishing ethics consideration for monitoring. Although wastewater surveillance to assess community infections is not a new idea, the coronavirus disease pandemic might be the initiating event to make this emerging public health tool a sustainable nationwide surveillance system, provided that these barriers are addressed.

The education community has conducted studies on failure rates and withdrawal rates between learning modalities in the past, but few studies have evaluated grade distribution between learning modes or focused specifically on English Composition. Using 2,919 student grades from the 2015-2016 academic year for an English Composition course, researchers examined failure rates, grade distribution, and withdrawal rates between In-Person learning, Online learning, and Synchronous video learning modes. In this study, learning modes and failure rates were related. Synchronous video modes of instruction had higher failure rates than traditional In-Person classes. Synchronous video classroom students failed at a higher rate than online students. Grade distributions showed significant differences based on learning mode. In-Person students earned more Bs and fewer Cs, Ds, and Fs than Online and synchronous video classroom students. In-Person students also withdrew at a significantly lower rate than online students. With these findings, we suggest that finding the root cause and alleviating the differences in student performance across learning modes should be a high priority for the educational community.

This study attempted to determine if placing videos in an asynchronous course influenced the learning experience. Data were examined for an introductory college statistics course comparing results pre and post implementation of videos in support of discussions, assignments, homework, quizzes, and exams. Frequency of external tutoring was significantly reduced 40% for the course sections that included embedded videos. This finding supports the idea that videos reduced the amount of friction or extraneous cognitive load experienced by students since using tutoring resources external to the course requires additional time and effort on the part of students and tutors. A significant majority of students agreed or strongly agreed that the videos helped them understand course concepts and how to perform course calculations. A significant majority of students also felt that course videos improved their knowledge of Microsoft Excel. However, there was not enough evidence found to support the idea that videos improved student grades or reduced tutoring time for those students who required it. Recommendations for future research includes repeating this study methodology accounting for gender, age, and ethnicity. Additionally, the methodology used in this study should be used in both traditional and non-traditional college settings.

Data from three sections of 200-level college statistics courses (student N = 85) were examined to evaluate the relationship between scaffolded assignments, time spent in the course, page views, and student performance. Strong positive correlations were noted between scaffolded assignments. Key formative and summative assignments also showed strong positive correlations indicating course effectiveness. Time students spent in the courses and their number of web page views yielded positive correlations with the end of course grades. Time spent completing key assignments such as homework preparation for the midterm and the midterm exam also showed positive correlations with student performance. However, time spent and page views failed to show strong positive correlations with short written assignments or discussions. Future research recommends using the study methodology to determine course effectiveness (relationship of formative and summative assessment scores) prior to measuring student performance in future research. The study methodology should be replicated in different university and college settings with varying term lengths. Future research should also include examining the quality of instructor/student interaction in discussion boards concerning student performance.

This study compared reported chemistry anxiety in an undergraduate chemistry course between online and classroom students. Results indicated slightly higher levels of anxiety for online students although findings were not statistically significant. However, activities resulting in high anxiety for both groups were identified. Gender was identified as a moderating variable with significantly more women than men indicating a high anxiety level when entering the lab and getting chemicals on their hands. Gender should be explored as a variable for anxiety and confidence when working with chemicals. Curriculum designers can also use the survey and methodology to evaluate their programs.

We apply the theory of collateral consequences and a social stress process framework to school discipline to examine whether exclusionary school discipline policies are associated with the mental health and wellbeing of adolescents who have never been suspended or expelled and whether this association varies across race/ethnicity. Data are from 8,878 adolescents in the National Longitudinal Study of Adolescent to Adult Health. Hierarchical linear models examined associations between discipline policies and adolescent depressive symptoms and school-connectedness, and modification by race/ethnicity. Schools had high levels of exclusionary discipline for both violent and non-violent infractions. More exclusionary policies were associated with higher levels of depressive symptoms (b = 1.03, 95% CI: 0.15, 1.91, p < 0.05). Sense of school-connectedness was not associated with disciplinary policies. Neither association was modified by race/ethnicity.

High quality feedback on assessments and deliverables is vital to student success. This pilot study sought to understand the impact of combining positive and performance-gap feedback in an immediate feedback scenario where students were provided multiple attempts to complete an assignment. 176 online undergraduate students were surveyed after completing a general inorganic chemistry course. Some students were provided performance-gap feedback, while others were provided performance-gap and positive feedback. The results suggest that type of feedback provided does not change students' perceptions and self-reported behaviors in the course. However, students who were provided both performance-gap and positive feedback received an average of an entire letter grade higher than the students who received only performance-gap feedback. These findings support the idea that a combination of feedback has a direct positive impact on students in an online setting.

This essay uses Brian Helgeland’s movie A Knight’s Tale (2001) as an example of modern medievalism and of a good choice for ESL and general studies students. Drawing on experiences from a course on films and television shows about the Middle Ages, taught at a technology university in Taiwan, I explore how this kind of class benefits Taiwanese ESL students, arguing in particular that a medievalism course can help both teachers and students to reflect on: (1) the need students have for some knowledge of medieval culture, which, entangled as it is in contemporary pop culture, they will encounter frequently in the films, TV shows, and video games that they enjoy; and (2) the need to think carefully about which texts to choose for ESL study.

Sequencing wastewater may be useful for detecting pathogens and assaying microbial water quality. We concentrated, extracted, and sequenced nucleic acids from 17 composite influent wastewater samples spanning seven southern California wastewater treatment facilities in May 2020. Bacteria were the most proportionally abundant taxonomic group present, followed by viruses and archaea.

Three years of data for 5,617 college online introductory statistics students were examined to determine if embedded course videos reduced incidences of external course tutoring. The frequency of external tutoring in course sections that used embedded videos was significantly reduced by 55% when compared to courses that did not use embedded course videos. These findings were consistent with an earlier study by Griffith & Faulconer (2022) where a statistically significant 40% reduction was found with a smaller sample size (26 months of data). Additionally, study results revealed a significant 51% reduction of tutoring hours for course sections that used embedded course videos. It was theorized that eliminating the need for students to seek external tutoring reduced cognitive load and friction for students which is particularly important in STEM courses taught in an online format. Recommendations include replicating this study methodology in traditional university settings with standard 16 week terms. Study results support the idea that faculty can use embedded course videos to reduce cognitive load and friction and reduce reliance on external tutoring by external tutoring organizations.

This article reports the development of a "course trailer" video series that communicates the professional and academic value of general education courses' core competencies and describes the results of a survey measuring the impact of those videos on student perception. Although general education programs represent a staple of U.S. undergraduate education, enrolled students frequently misunderstand the nature and value of the programs' core goals and or competencies. Universities are making increasing use of devices such as catalog descriptions, mission statements, course websites or blogs, and course trailer videos to communicate and clarify their general education competencies and values; however, little empirical research exists demonstrating the efficacy of such devices. This study's results provide statistically significant evidence that the course trailer video series improved students' understanding of how general education course fit into both their academic and professional plans.

Undergraduate research benefits students by strengthening skills, providing professional growth, and improving retention. Yet significant barriers exist, including low awareness of opportunities, restrictive cultural norms, and resource constraints. The proliferation of online education potentially increases barriers, both real and perceived. This study compared participation rates and perceived barriers between undergraduate distance and traditional students. Survey results indicated no significant differences in self-reported participation or overall interest in research. Despite inherent structural limitations of online education, there were no significant differences in the respondents' perceptions of access to opportunities, physical resources, or human resources. Significant differences were seen regarding awareness of research opportunities. Although institution-specific moderating factors may influence results, this information is valuable for strategic planning aimed at increasing opportunities and awareness for undergraduates.

The university traditionally has been the foundation for young adults' professional development, yet the proclivity toward safety culture has garnered less focus in higher education than in the workforce. A survey of faculty at a medium-sized, research-active, private institution revealed specific areas of policy noncompliance as well as specific safety attitudes that can be targeted for interventions. Albeit a snapshot view, the survey implies that safety needs better representation in the classroom, teaching laboratories, and research facilities at universities. Safety is not abandoned by any means, and there is a strong presence of safety-oriented individuals, but the data show barriers to safety do exist that need to be addressed. The implications of this small-scale study serve as a foundation for a more comprehensive multi-institutional study in the future.

Rainstorms increase levels of fecal indicator bacteria in urban coastal waters, but it is unknown whether exposure to seawater after rainstorms increases rates of acute illness. Our objective was to provide the first estimates of rates of acute illness after seawater exposure during both dry- and wet-weather periods and to determine the relationship between levels of indicator bacteria and illness among surfers, a population with a high potential for exposure after rain. We enrolled 654 surfers in San Diego, California, and followed them longitudinally during the 2013-2014 and 2014-2015 winters (33,377 days of observation, 10,081 surf sessions). We measured daily surf activities and illness symptoms (gastrointestinal illness, sinus infections, ear infections, infected wounds). Compared with no exposure, exposure to seawater during dry weather increased incidence rates of all outcomes (e.g., for earache or infection, adjusted incidence rate ratio (IRR) = 1.86, 95% confidence interval (CI): 1.27, 2.71; for infected wounds, IRR = 3.04, 95% CI: 1.54, 5.98); exposure during wet weather further increased rates (e.g., for earache or infection, IRR = 3.28, 95% CI: 1.95, 5.51; for infected wounds, IRR = 4.96, 95% CI: 2.18, 11.29). Fecal indicator bacteria measured in seawater (Enterococcus species, fecal coliforms, total coliforms) were strongly associated with incident illness only during wet weather. Urban coastal seawater exposure increases the incidence rates of many acute illnesses among surfers, with higher incidence rates after rainstorms.

BackgroundColiphages have been proposed as indicators of fecal contamination in recreational waters because they better mimic the persistence of pathogenic viruses in the environment and wastewater treatment than fecal indicator bacteria. We estimated the association between coliphages and gastrointestinal illness and compared it with the association with culturable enterococci.MethodsWe pooled data from six prospective cohort studies that enrolled coastal beachgoers in California, Alabama, and Rhode Island. Water samples were collected and gastrointestinal illness within 10 days of the beach visit was recorded. Samples were tested for enterococci and male-specific and somatic coliphages. We estimated cumulative incidence ratios (CIR) for the association between swimming in water with detectable coliphage and gastrointestinal illness when human fecal pollution was likely present, not likely present, and under all conditions combined. The reference group was unexposed swimmers. We defined continuous and threshold-based exposures (coliphage present/absent, enterococci >35 vs. ≤35 CFU/100 ml).ResultsUnder all conditions combined, there was no association between gastrointestinal illness and swimming in water with detectable coliphage or enterococci. When human fecal pollution was likely present, coliphage and enterococci were associated with increased gastrointestinal illness, and there was an association between male-specific coliphage level and illness that was somewhat stronger than the association between enterococci and illness. There were no substantial differences between male-specific and somatic coliphage.ConclusionsSomatic coliphage and enterococci had similar associations with gastrointestinal illness; there was some evidence that male-specific coliphage had a stronger association with illness than enterococci in marine waters with human fecal contamination.

ObjectivesTo provide summary estimates of gastroenteritis risks and illness burden associated with recreational water exposure and determine whether children have higher risks and burden.MethodsWe combined individual participant data from 13 prospective cohorts at marine and freshwater beaches throughout the United States (n = 84 411). We measured incident outcomes within 10 days of exposure: diarrhea, gastrointestinal illness, missed daily activity (work, school, vacation), and medical visits. We estimated the relationship between outcomes and 2 exposures: body immersion swimming and Enterococcus spp. fecal indicator bacteria levels in the water. We also estimated the population-attributable risk associated with these exposures.ResultsWater exposure accounted for 21% of diarrhea episodes and 9% of missed daily activities but was unassociated with gastroenteritis leading to medical consultation. Children aged 0 to 4 and 5 to 10 years had the most water exposure, exhibited stronger associations between levels of water quality and illness, and accounted for the largest attributable illness burden.ConclusionsThe higher gastroenteritis risk and associated burden in young children presents important new information to inform future recreational water quality guidelines designed to protect public health.

Education researchers have conducted studies on the relationship of learning mode to student performance, but few studies have evaluated pass rate, grade distribution and student withdrawal rate in an introductory research methods course. In this study, researchers examined 2,097 student grades from the 2015-2016 academic year to determine if such a relationship existed. In this study, learning mode was significantly related to failure rate, grade distribution and withdraw rate. Synchronous video home students had a significantly higher failure rate than traditional In-Person or online students. Online student grade distributions were significantly different than In-Person classroom, synchronous video home or synchronous video classroom students. Online Students tended to earn more "A"s and fewer "B"s and "D"s. Synchronous video home students also had a significantly higher withdraw rate than synchronous video classroom students. Recommendations for further research include investigating variables which may impact student performance such as faculty experience with course content and technology and how students select learning modes when taking classes. Future research should continue to employ outcome-based studies to measure the impact of learning mode on student performance. This remains a key issue from the perspective of the students and the institution.

IntroductionAdvances in molecular methods provide new opportunities for directly measuring pathogens or host-associated markers of fecal pollution instead of relying on fecal indicator bacteria (FIB) alone for beach water quality monitoring. Adoption of new indicators depends on identifying relationships between either the presence or concentration of the indicators and illness among swimmers. Here we present results from three epidemiologic studies in which a broad range of bacterial and viral indicators of fecal contamination were measured simultaneously by either culture or molecular methods along with Enterococcus to assess whether they provide better health risk prediction than current microbial indicators of recreational water quality.MethodsWe conducted prospective cohort studies at three California beaches -- Avalon Bay (Avalon), Doheny State Beach (Doheny), Surfrider State Beach (Malibu) -- during the summers of 2007, 2008 and 2009. The studies enrolled 10,785 swimmers across the beaches and recorded each swimmer's water exposure. Water and sand samples were collected several times per day at multiple locations at each beach and analyzed for up to 41 target indicators using 67 different methodologies. Interviewers contacted participants by phone 10-14 days later and recorded symptoms of gastrointestinal illness occurring after their beach visit. Regression models were used to evaluate the association between water quality indicators and gastrointestinal illness among swimmers at each beach.ResultsF+ coliphage (measured using EPA Method 1602) exhibited a stronger association with GI illness than did EPA Method 1600 at the two beaches where it was measured, while a molecular method, F+ RNA Coliphage Genotype II, was the only indicator significantly associated with GI illness at Malibu. MRSA, a known pathogen, had the strongest association with GI illness of any microbe measured at Avalon. There were two methods targeting human-associated fecal anaerobic bacteria that were more strongly associated with GI illness than EPA Method 1600, but only at Avalon. No indicator combinations consistently had a higher odds ratio than EPA Method 1600, but one composite indicator, based on the number of pathogens detected at a beach, was significantly associated with gastrointestinal illness at both Avalon and Doheny when freshwater flow was high.DiscussionWhile EPA Method1600 performed adequately at two beaches based on its consistency of association with gastrointestinal illness and the precision of its estimated associations, F+ coliphage measured by EPA Method 1602 had a stronger association with GI illness under high risk conditions at the two beaches where it was measured. One indicator, F+ Coliphage Genotype II was the only indicator significantly associated with GI illness at Malibu. Several indicators, particularly those targeting human associated bacteria, exhibited relationships with GI illness that were equal to or greater than that of EPA Method 1600 at Avalon, which has a focused human fecal source. Our results suggest that site-specific conditions at each beach determine which indicator or indicators best predict GI illness.