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Abstract: Following Efron (2014), we propose an algorithm for estimating treatment effects for use by researchers employing a regression-discontinuity (RD) design. This algorithm generates a set of estimates of the treatment effect from bootstrapped samples, wherein the polynomial-selection algorithm developed by Pei, Lee, Card, and Weber (2021) is applied to each sample, the average of these RD treatment effect (RDTE) estimates is computed and serves as the overall estimate of the RDTE. Effectively, this procedure estimates a set of plausible RD estimates and weights the estimates by their likelihood of being the best estimate to form a weighted-average estimate. We discuss why this procedure may lower the estimate’s root mean squared error (RMSE). In simulation results, we show that this better performance is achieved, yielding up to a 5% reduction in RMSE relative to PLCW’s method and a 16% reduction in RMSE relative to Calonico, Cattaneo, and Titiunik’s (2014) method for bandwidth selection (with default settings).

Background: It is widely recognised that policymakers use research deemed relevant, yet little is understood about ways to enhance perceived relevance of research evidence. Observing policymakers' access of research online provides a pragmatic way to investigate predictors of relevance. Aims and objectives: This study investigates a range of relevance indicators including committee assignments, public statements, issue prevalence, or the policymaker's name or district. Methods: In a series of four rapid-cycle randomised control trials (RCTs), the present work systematically explores science communication strategies by studying indicators of perceived relevance. State legislators, state staffers, and federal staffers were emailed fact sheets on issues of COVID (Trial 1, N = 3403), exploitation (Trial 2, N = 6846), police violence (Trial 3, N = 3488), and domestic violence (Trial 4, N = 3888). Findings: Across these trials, personalising the subject line to the legislator's name or district and targeting recipients based on committee assignment consistently improved engagement. Mentions of subject matter in public statements was inconsistently associated, and state-level prevalence of the issue was largely not associated with email engagement behaviour. Discussion and conclusions: Together, these results indicate a benefit of targeting legislators based on committee assignments and of personalising the subject line with legislator information. This work further operationalises practical indicators of personal relevance and demonstrates a novel method of how to test science communication strategies among policymakers. Building enduring capacity for testing science communication will improve tactics to cut through the noise during times of political crisis.

Dengue virus (DENV) transmission from humans to mosquitoes is a poorly documented, but critical component of DENV epidemiology. Magnitude of viremia is the primary determinant of successful human-to-mosquito DENV transmission. People with the same level of viremia, however, can vary in their infectiousness to mosquitoes as a function of other factors that remain to be elucidated. Here, we report on a field-based study in the city of Iquitos, Peru, where we conducted direct mosquito feedings on people naturally infected with DENV and that experienced mild illness. We also enrolled people naturally infected with Zika virus (ZIKV) after the introduction of ZIKV in Iquitos during the study period. Of the 54 study participants involved in direct mosquito feedings, 43 were infected with DENV-2, two with DENV-3, and nine with ZIKV. Our analysis excluded participants whose viremia was detectable at enrollment but undetectable at the time of mosquito feeding, which was the case for all participants with DENV-3 and ZIKV infections. We analyzed the probability of onward transmission during 50 feeding events involving 27 participants infected with DENV-2 based on the presence of infectious virus in mosquito saliva 7-16 days post blood meal. Transmission probability was positively associated with the level of viremia and duration of extrinsic incubation in the mosquito. In addition, transmission probability was influenced by the day of illness in a non-monotonic fashion; i.e., transmission probability increased until 2 days after symptom onset and decreased thereafter. We conclude that mildly ill DENV-infected humans with similar levels of viremia during the first two days after symptom onset will be most infectious to mosquitoes on the second day of their illness. Quantifying variation within and between people in their contribution to DENV transmission is essential to better understand the biological determinants of human infectiousness, parametrize epidemiological models, and improve disease surveillance and prevention strategies.

Net-zero greenhouse gas (GHG) emissions targets are driving interest in opportunities for biomass-based negative emissions and bioenergy, including from marine sources such as seaweed. Yet the biophysical and economic limits to farming seaweed at scales relevant to the global carbon budget have not been assessed in detail. We use coupled seaweed growth and technoeconomic models to estimate the costs of global seaweed production and related climate benefits, systematically testing the relative importance of model parameters. Under our most optimistic assumptions, sinking farmed seaweed to the deep sea to sequester a gigaton of CO2 per year costs as little as US$480 per tCO2 on average, while using farmed seaweed for products that avoid a gigaton of CO2-equivalent GHG emissions annually could return a profit of $50 per tCO2-eq. However, these costs depend on low farming costs, high seaweed yields, and assumptions that almost all carbon in seaweed is removed from the atmosphere (that is, competition between phytoplankton and seaweed is negligible) and that seaweed products can displace products with substantial embodied non-CO2 GHG emissions. Moreover, the gigaton-scale climate benefits we model would require farming very large areas (>90,000 km2)-a >30-fold increase in the area currently farmed. Our results therefore suggest that seaweed-based climate benefits may be feasible, but targeted research and demonstrations are needed to further reduce economic and biophysical uncertainties.

Current knowledge of dengue virus (DENV) transmission provides only a partial understanding of a complex and dynamic system yielding a public health track record that has more failures than successes. An important part of the problem is that the foundation for contemporary interventions includes a series of longstanding, but untested, assumptions based on a relatively small portion of the human population; i.e., people who are convenient to study because they manifest clinically apparent disease. Approaching dengue from the perspective of people with overt illness has produced an extensive body of useful literature. It has not, however, fully embraced heterogeneities in virus transmission dynamics that are increasingly recognized as key information still missing in the struggle to control the most important insect-transmitted viral infection of humans. Only in the last 20 years have there been significant efforts to carry out comprehensive longitudinal dengue studies. This manuscript provides the rationale and comprehensive, integrated description of the methodology for a five-year longitudinal cohort study based in the tropical city of Iquitos, in the heart of the Peruvian Amazon. Primary data collection for this study was completed in 2019. Although some manuscripts have been published to date, our principal objective here is to support subsequent publications by describing in detail the structure, methodology, and significance of a specific research program. Our project was designed to study people across the entire continuum of disease, with the ultimate goal of quantifying heterogeneities in human variables that affect DENV transmission dynamics and prevention. Because our study design is applicable to other Aedes transmitted viruses, we used it to gain insights into Zika virus (ZIKV) transmission when during the project period ZIKV was introduced and circulated in Iquitos. Our prospective contact cluster investigation design was initiated by detecttion of a person with a symptomatic DENV infection and then followed that person's immediate contacts. This allowed us to monitor individuals at high risk of DENV infection, including people with clinically inapparent and mild infections that are otherwise difficult to detect. We aimed to fill knowledge gaps by defining the contribution to DENV transmission dynamics of (1) the understudied majority of DENV-infected people with inapparent and mild infections and (2) epidemiological, entomological, and socio-behavioral sources of heterogeneity. By accounting for factors underlying variation in each person's contribution to transmission we sought to better determine the type and extent of effort needed to better prevent virus transmission and disease.

Given the individual and systemic stress endured by children and families during the COVID-19 pandemic, research examining culturally responsive school experiences and supports to enhance resilience is critical. This study examined the relationship between caregivers' perceptions of COVID-19 impact, mental health distress among children and caregivers, and school-based sociocultural protective factors, including culturally responsive practices in schools and the relationships between teachers and caregivers, concurrently and longitudinally. Data were collected from caregivers of elementary-aged children at two-time points from March to April 2020 (N = 174) and one year later in 2021 (N = 114). Regression analyses revealed that COVID-19 impact positively predicted and parent-teacher joining negatively predicted mental health concerns among children and families, concurrently and longitudinally. Furthermore, there was a positive relationship between caregivers' perceptions of teachers' social awareness and justice practices and mental health symptoms for children in 2020. Parent-teacher joining longitudinally moderated the relationship between COVID-19 impact and caregivers' mental health concerns. This study provides implications regarding sociocultural resilience factors that should be considered in schools amidst the COVID-19 pandemic.

The 2020-2021 academic year brought numerous challenges to teachers across the country as they worked to educate students amidst the COVID-19 pandemic. The current study is a secondary data analysis of qualitative responses collected as part of a teacher survey to evaluate a social emotional learning curriculum implemented during the 2020-2021 academic year. The lived experiences of teachers (N = 52) across 11 elementary schools in the Great Plains region were captured through open-ended questions as the teachers transitioned from in-person to remote learning. A phenomenological approach was utilized to analyze the challenges expressed by teachers as they faced instability and additional professional demands. Given that stress and other factors that strain mental health exist within multiple layers of an individual's social ecology, a modified social-ecological framework was used to organize the results and themes. Findings suggest that during the academic year, teachers experienced stressors related to their personal and professional roles, concerns for students' well-being which extended beyond academics, and frustrations with administration and other institutional entities around COVID safety measures. Without adequate support and inclusion of teacher perspectives, job-related stress may lead to teacher shortages, deterioration of teacher mental health, and ultimately worse outcomes for students. Implications for policy, research, and practice are discussed.

Indiana, Oklahoma, and Washington each have programs designed to address college enrollment gaps by offering a promise of state-based college financial aid to low-income middle school students in exchange for making a pledge to do well in high school, be a good citizen, not be convicted of a felony, and apply for financial aid to college. Using a triple-difference specification, we estimate the effects of Washington's College Bound Scholarship program on students' high school grades, high school graduation, juvenile detention and rehabilitation, and incarceration in state prison during high school or early adulthood. We find insignificant and substantively small or negative effects on these outcomes. These results call into question the rationale for such early commitment programs.

To evaluate how Advanced Placement (AP) courses affect college-going, we randomly assigned the offer of enrollment into an AP science course to over 1,800 students in twenty-three schools that had not previously offered the course. We find no AP course effects on students' college entrance exam scores (SAT/ACT). As expected, AP course-takers are substantially more likely to take the AP exam than their control group counterparts. At the same time, treatment group students opt out of the exam at very high rates and most do not earn a passing score on the AP exam. Though less precisely estimated, the results also suggest that taking the AP course increases students' aspirations to attend higher-quality colleges but does not lead to enrollment in such institutions.

Children with intellectual disability experience significant challenges in accessing and receiving high-quality healthcare leading to poorer health outcomes and negative patient experiences. Families of these children often report a need for healthcare staff to better understand, communicate, and collaborate for better care while staff acknowledge a lack of training. To address this, we utilised an action research framework with a pre- and post-survey to evaluate an integrated continuing professional development and quality improvement program combining strategies from education, behavioural psychology and quality improvement that was delivered in two departments within a tertiary children's Hospital in Metropolitan Sydney in 2019-2020. Parents reported noticeable changes in the clinical practice of staff, and staff acknowledged and attributed their shift in behaviour to raising awareness and discussions around necessary adaptations. The program demonstrates a novel method for knowledge translation to practice and systems improvements.

To the Editor.--Congenital rubella can cause significant morbidity and mortality but is rare in countries with vaccination and immune status verification programs. Testing for anti-rubella virus immunoglobulin G (IgG) and [...]