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State and federal agencies regulate fecal indicator bacteria (FIB), such as E. coli or Enterococcus, in order to manage public health risks at swimming beaches. Despite these goals, watershed managers are challenged in terms of how to best clean up sources of FIB because concentrations frequently exceed water quality objectives, and sources—both human and nonhuman sources of FIB—appear to be everywhere. Since most nonhuman fecal sources represent substantially lower public health risks than human sources do, this study utilizes the human fecal source marker HF183 to better define watershed managers’ riskiest sites and times in order to prioritize remediation actions. A total of 117 samples were collected and analyzed for both FIB and HF183 from 26 sites during multiple sampling campaigns between 2019 and 2021 along the mainstem in addition to major tributaries in a highly urbanized watershed. The results indicated that the vast majority of samples (96%) quantified HF183 during wet weather, ranging from 99 to 44,768 gene copies/100 mL. Similar to HF183, the FIB results exceeded water quality objectives for 100% of the samples in wet weather; however, HF183 was rarely quantified in dry weather, with 3 of 72 samples (4%) exceeding 500 gene copies/100 mL, while two-thirds of samples (67%) exceeded FIB water quality objectives during dry weather. Where HF183 was detected in dry weather, isolated and unpredictable events explained human fecal pollution. It is more challenging in wet weather to identify and quantify the source(s) of human fecal pollution.

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. For example, bacterial pathogens from both marine and terrestrial sources concentrate in oysters and can cause human illness when oysters are consumed raw. 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 oyster hosts and the microbial ecology of pathogenic bacteria 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 fecal indicators,Vibrio parahaemolyticus, andVibrio vulnificus. Site-specific environmental conditions significantly influenced the composition and diversity of water microbial communities, which were linked to the highest concentrations of bothVibriospp. and fecal indicator bacteria. Oyster microbial communities, however, were less impacted by environmental variability and exhibited less variability in microbial community diversity and accumulation of target bacteria. Instead, changes in specific microbial taxa in oyster and water samples, particularly in oyster digestive glands, were linked to elevated potential pathogens in oysters, especiallyV. parahaemolyticus. This included an increase in cyanobacteria in both water and oyster digestive gland microbial communities, which could represent an environmental vector forVibriospp. transport and decreased relative abundance ofMycoplasmaand 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.

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.

Social support is closely linked to health, but little is known about United States (U.S.) veterans' social support over time and factors that may influence their support trajectories. This study investigates social support over time for U.S. men and women Post-9/11 veterans in relation to trauma history and gender. A secondary analysis of longitudinal cohort data from the Survey of Experiences of Returning Veterans (SERV), which employed a repeated-measures longitudinal design using five waves of data (baseline, 3, 6, 9, 12 months) with 672 combat veterans. Results from random intercept multilevel models found no significant gender differences in social support over time. Veterans with complex trauma histories were at risk for lower social support across waves. A stability trend was also observed; specifically, at baseline, veterans who started with high support maintained their level over time whereas veterans who started with deficits in social support remained low over time. Veterans identifying as African American or Latinx, and those with lower annual incomes, reported lower support compared to White and higher-income veterans. Furthermore, low social support was significantly associated with severe posttraumatic stress symptoms and active suicidal ideation across 12 months. SERV utilized a nonrandom sampling method that may reduce generalizability of findings. There is also potential for residual confounding by factors related to both social support levels and time since discharge that were not available in this data set. Findings have implications for developing clinical and community interventions intended to support veterans as they transition back to the community. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The present study examined revictimization, defined as sexual or physical assault in adulthood that followed a history of childhood maltreatment. We aimed to identify factors associated with revictimization over time in a group of U.S. military veterans deployed following the September 11, 2001, terrorist attacks (9/11). As revictimization is associated with multiple negative mental health outcomes in the literature, identifying risk and protective factors can aid in the prevention of revictimization and associated poor health outcomes among veterans. In this sample, the proportion of adult revictimization was 2.7% for men, 95% CI [2.0, 3.6] and 22.9% for women, 95% CI [20.5, 25.8]. Using multilevel logistic models, we found that women, β = 2.2, p .001; Navy veterans, β = 1.5, p .001; and participants who reported posttraumatic stress symptoms, β = 0.2, p = .028, were at significantly higher risk of revictimization across time compared to nonrevictimized counterparts. Social support while in the military was protective, β = -0.1, p .001, against revictimization. In addition, childhood abuse experiences combined with characteristics such as female gender were related to an increased risk of revictimization during and following military service. The findings highlight opportunities for intervention and areas of strength within this population; social connection garnered during military service may serve as a protective factor against revictimization. Future research is needed to examine the role of social support in possibly lowering veterans' risk of revictimization over time, particularly for post-9/11 veterans struggling with transitioning from military to civilian life.

Research shows that though some students can easily find the correct solutions to the problem(s) at hand, the algorithms that these students create are not always ones that would, when implemented, produce the correct solution(s). Towards shedding light on this phenomenon, the present study explicates a mechanism—accounting for features of the solution—by which students create algorithms. Via this mechanism, students notice particular features of the solution they found, then create specific rules (instructions) within their algorithm, which guarantee that the algorithm outputs an object that possesses the noticed features. Thus, an algorithm can produce the solution only if the object it outputs has all the features of the solution. In this paper, I explicate the accounting for mechanism within the collaborative work of two groups of students on a contextualised graph theory task, which invited the groups to create an algorithm for finding an optimal seating arrangement. Both groups found an optimal seating arrangement and seemingly employed the accounting for mechanism to create their respective algorithms. However, only one group’s algorithm could actually produce the optimal arrangement. The questions explored in this study are: (1) What sorts of features of their solutions did the two groups account for? and (2) What differences (if any) between the features accounted for by the respective groups, might explain why only one group’s algorithm could produce the optimal arrangement?

Summary Background Radical surgery via total mesorectal excision might not be the optimal first-line treatment for early-stage rectal cancer. An organ-preserving strategy with selective total mesorectal excision could reduce the adverse effects of treatment without substantially compromising oncological outcomes. We investigated the feasibility of recruiting patients to a randomised trial comparing an organ-preserving strategy with total mesorectal excision. Methods TREC was a randomised, open-label feasibility study done at 21 tertiary referral centres in the UK. Eligible participants were aged 18 years or older with rectal adenocarcinoma, staged T2 or lower, with a maximum diameter of 30 mm or less; patients with lymph node involvement or metastases were excluded. Patients were randomly allocated (1:1) by use of a computer-based randomisation service to undergo organ preservation with short-course radiotherapy followed by transanal endoscopic microsurgery after 8–10 weeks, or total mesorectal excision. Where the transanal endoscopic microsurgery specimen showed histopathological features associated with an increased risk of local recurrence, patients were considered for planned early conversion to total mesorectal excision. A non-randomised prospective registry captured patients for whom randomisation was considered inappropriate, because of a strong clinical indication for one treatment group. The primary endpoint was cumulative randomisation at 12, 18, and 24 months. Secondary outcomes evaluated safety, efficacy, and health-related quality of life assessed with the European Organisation for Research and Treatment of Cancer (EORTC) QLQ C30 and CR29 in the intention-to-treat population. This trial is registered with the ISRCTN Registry, ISRCTN14422743. Findings Between Feb 22, 2012, and Dec 19, 2014, 55 patients were randomly assigned at 15 sites; 27 to organ preservation and 28 to radical surgery. Cumulatively, 18 patients had been randomly assigned at 12 months, 31 at 18 months, and 39 at 24 months. No patients died within 30 days of initial treatment, but one patient randomly assigned to organ preservation died within 6 months following conversion to total mesorectal excision with anastomotic leakage. Eight (30%) of 27 patients randomly assigned to organ preservation were converted to total mesorectal excision. Serious adverse events were reported in four (15%) of 27 patients randomly assigned to organ preservation versus 11 (39%) of 28 randomly assigned to total mesorectal excision (p=0·04, χ2 test). Serious adverse events associated with organ preservation were most commonly due to rectal bleeding or pain following transanal endoscopic microsurgery (reported in three cases). Radical total mesorectal excision was associated with medical and surgical complications including anastomotic leakage (two patients), kidney injury (two patients), cardiac arrest (one patient), and pneumonia (two patients). Histopathological features that would be considered to be associated with increased risk of tumour recurrence if observed after transanal endoscopic microsurgery alone were present in 16 (59%) of 27 patients randomly assigned to organ preservation, versus 24 (86%) of 28 randomly assigned to total mesorectal excision (p=0·03, χ2 test). Eight (30%) of 27 patients assigned to organ preservation achieved a complete response to radiotherapy. Patients who were randomly assigned to organ preservation showed improvements in patient-reported bowel toxicities and quality of life and function scores in multiple items compared to those who were randomly assigned to total mesorectal excision, which were sustained over 36 months’ follow-up. The non-randomised registry comprised 61 patients who underwent organ preservation and seven who underwent radical surgery. Non-randomised patients who underwent organ preservation were older than randomised patients and more likely to have life-limiting comorbidities. Serious adverse events occurred in ten (16%) of 61 non-randomised patients who underwent organ preservation versus one (14%) of seven who underwent total mesorectal excision. 24 (39%) of 61 non-randomised patients who underwent organ preservation had high-risk histopathological features, while 25 (41%) of 61 achieved a complete response. Overall, organ preservation was achieved in 19 (70%) of 27 randomised patients and 56 (92%) of 61 non-randomised patients. Interpretation Short-course radiotherapy followed by transanal endoscopic microsurgery achieves high levels of organ preservation, with relatively low morbidity and indications of improved quality of life. These data support the use of organ preservation for patients considered unsuitable for primary total mesorectal excision due to the short-term risks associated with this surgery, and support further evaluation of short-course radiotherapy to achieve organ preservation in patients considered fit for total mesorectal excision. Larger randomised studies, such as the ongoing STAR-TREC study, are needed to more precisely determine oncological outcomes following different organ preservation treatment schedules. Funding Cancer Research UK.

Our project seeks to draw attention to the rich mathematical thinking that is generated when students work on contextual mathematising tasks. We use a design-based research approach to create ways of reporting that raise the visibility of this rich mathematical thinking while retaining and respecting its complexity. These reports will be aimed for three classroom stakeholders: (1) students, who wish to reflect on and enhance their mathematical learning; (2) teachers, who wish to integrate contextual mathematising tasks into their teaching practice and (3) researchers, who seek rich tasks for generating observable instances of mathematical thinking and learning. We anticipate that these reports and the underlying theoretical framework for creating them will contribute to greater awareness of and appreciation for the mathematical value of contextual mathematising tasks in learning, teaching and research.

Summary Background Emergency abdominal surgery is associated with poor patient outcomes. We studied the effectiveness of a national quality improvement (QI) programme to implement a care pathway to improve survival for these patients. Methods We did a stepped-wedge cluster-randomised trial of patients aged 40 years or older undergoing emergency open major abdominal surgery. Eligible UK National Health Service (NHS) hospitals (those that had an emergency general surgical service, a substantial volume of emergency abdominal surgery cases, and contributed data to the National Emergency Laparotomy Audit) were organised into 15 geographical clusters and commenced the QI programme in a random order, based on a computer-generated random sequence, over an 85-week period with one geographical cluster commencing the intervention every 5 weeks from the second to the 16th time period. Patients were masked to the study group, but it was not possible to mask hospital staff or investigators. The primary outcome measure was mortality within 90 days of surgery. Analyses were done on an intention-to-treat basis. This study is registered with the ISRCTN registry, number ISRCTN80682973. Findings Treatment took place between March 3, 2014, and Oct 19, 2015. 22 754 patients were assessed for elegibility. Of 15 873 eligible patients from 93 NHS hospitals, primary outcome data were analysed for 8482 patients in the usual care group and 7374 in the QI group. Eight patients in the usual care group and nine patients in the QI group were not included in the analysis because of missing primary outcome data. The primary outcome of 90-day mortality occurred in 1210 (16%) patients in the QI group compared with 1393 (16%) patients in the usual care group (HR 1·11, 0·96–1·28). Interpretation No survival benefit was observed from this QI programme to implement a care pathway for patients undergoing emergency abdominal surgery. Future QI programmes should ensure that teams have both the time and resources needed to improve patient care. Funding National Institute for Health Research Health Services and Delivery Research Programme.