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The Useful Field of View task (UFOV) is a strong and reliable predictor of crash risk in older drivers. However, while the functional domain of attention is clearly implicated in UFOV performance, the potential role of one specific attentional process remains unclear: attentional breadth (the spatial extent of the attended region around the point of visual fixation). The goal of the present study was to systematically test the role of two distinct aspects of attentional breadth, maintaining a specific breadth of attention and resizing the attended region, in UFOV performance. To this end, 135 older adults completed the UFOV and modified Navon tasks to measure their efficiency in maintaining, contracting, and expanding the breadth of attention. We then examined individual-difference associations between these aspects of attentional breadth deployment and UFOV performance. We found that performance on UFOV Subtask 2 was associated with efficient contraction of attentional breadth (i.e., resizing the attended region to a smaller area), while Subtask 3 performance was associated with the efficiency of expanding attentional breadth (i.e., resizing the attended region to a larger area). The selectivity of these relationships appears to implicate these specific deployments of attentional breadth in how people complete the task, as it suggests that these relationships are not simply attributable to shared variance in a broader domain of cognitive functioning. The implications of these results for our understanding of UFOV, as well as future research directions that test the relative contributions of different cognitive processes in predicting task performance, are discussed.

Trachoma, caused by ocular Chlamydia trachomatis infection, is targeted for global elimination as a public health problem by 2030. To provide evidence for use of antibodies to monitor C. trachomatis transmission, we collated IgG responses to Pgp3 antigen, PCR positivity, and clinical observations from 19,811 children aged 1-9 years in 14 populations. We demonstrate that age-seroprevalence curves consistently shift along a gradient of transmission intensity: rising steeply in populations with high levels of infection and active trachoma and becoming flat in populations near elimination. Seroprevalence (range: 0-54%) and seroconversion rates (range: 0-15 per 100 person-years) correlate with PCR prevalence (r: 0.87, 95% CI: 0.57, 0.97). A seroprevalence threshold of 13.5% (seroconversion rate 2.75 per 100 person-years) identifies clusters with any PCR-identified infection at high sensitivity ( >90%) and moderate specificity (69-75%). Antibody responses in young children provide a robust, generalizable approach to monitor population progress toward and beyond trachoma elimination.

Physics Education Research has a rich history of identifying common student ideas about specific physics topics. In the context of electric circuits, existing research on students’ ideas has primarily focused on misconceptions, misunderstandings, and difficulties. In this paper, we take a resource-oriented approach to identifying common student ideas about circuits by characterizing ideas we see as generative “seeds of science” that could form the basis of more sophisticated understandings. Based on our analysis of 1557 university physics student responses to five conceptual questions, we identify four common resources for understanding circuits.

[This paper is part of the Focused Collection on Qualitative Methods in PER: A Critical Examination.] Identifying student ideas about particular physics topics is one of the earliest and longest-standing foci of physics education research. This paper presents a method for identifying common conceptual resources for understanding physics, using large numbers of written student responses to conceptual questions. We walk researchers step by step through how we have done this ourselves, from collecting data, to identifying candidate resources, to turning our lists of candidate resources into a coding scheme that can then be applied to datasets of >200 responses. The outcome of these methods are lists of common conceptual resources for understanding particular topics in physics, such as forces, energy, circuits, and heat and temperature.

The MORDOR trial in Niger, Malawi, and Tanzania found that biannual mass distribution of azithromycin to children younger than 5 years led to a 13.5% reduction in all-cause mortality (NCT02048007). To help elucidate the mechanism for mortality reduction, we report IgG responses to 11 malaria, bacterial, and protozoan pathogens using a multiplex bead assay in pre-specified substudy of 30 communities in the rural Niger placebo-controlled trial over a three-year period (n = 5642 blood specimens, n = 3814 children ages 1-59 months). Mass azithromycin reduces Campylobacter spp. force of infection by 29% (hazard ratio = 0.71, 95% CI: 0.56, 0.89; P = 0.004) but serological measures show no significant differences between groups for other pathogens against a backdrop of high transmission. Results align with a recent microbiome study in the communities. Given significant sequelae of Campylobacter infection among preschool aged children, our results support an important mechanism through which biannual mass distribution of azithromycin likely reduces mortality in Niger.

Abstract The tree-level wavefunction coefficient for four gravitons in de Sitter space was recently bootstrapped using the Cosmological Optical Theorem, flat space limit, and Manifestly Local Test [1]. Inspired by the double copy for scattering amplitudes, we derive a compact new expression for this quantity starting from the wavefunction coefficient for gluons.

Mastering construction times is of paramount importance in making vernacular earth construction techniques attractive to modern clients. The work presented here is a contribution towards the optimization of the construction time of cob buildings. Therefore, this paper follows the evolution of a cob’s mechanical properties during its drying process in the case of a double-walling CobBauge system. Laboratory tests and in situ measurements were performed, and further results were described. Volumetric water content sensors were immersed in the walls of a CobBauge prototype building during its construction. The evolution of the cob layer’s compressive strength and Clegg Impact Value (CIV) as a function of its water content has been experimentally studied and discussed. These studies showed that compressive strength and CIV are correlated with water content, and both properties decrease exponentially with time. In this study, a new tool to evaluate cob’s mechanical performances in situ has been proposed, Clegg Impact Soil Tester. This was linked to compressive strength, and a linear relationship between these two properties was found. Finally, appropriate values of compressive strength and CIV to satisfy before formwork stripping and re-lifting were proposed. For this study’s conditions, these values are reached after approximately 27 days.

Perhaps the most commonly cited student idea about forces in the literature is the notion of an impetus force, defined as the "belief that there is a force inside a moving object that keeps it going and causes it to have some speed," that can then "fade away as the object moves along." According to the literature, even after physics instruction students use impetus force reasoning to argue that forces are necessary to sustain motion or that motion implies force. For example, many students drew an upward arrow to indicate a force on a coin that was moving upward after being tossed. The coin was halfway between the point of its release and its turnaround point. Interviews with students in the course indicate that the arrow was meant to indicate "the 'force of the throw,' the 'upward original force,'" and so on. Clement interprets these results to mean that students "believe that continuing motion implies the presence of a continuing force in the same direction, as a necessary cause of the motion."

Abstract We compute the tree-level late-time graviton four-point correlation function, and the related quartic wavefunction coefficient, for Einstein gravity in de Sitter spacetime. We derive this result in several ways: by direct calculation, using the in-in formalism and the wavefunction of the universe; by a heuristic derivation leveraging the flat space wave-function coefficient; and by using the boostless cosmological bootstrap, in particular the combination of the cosmological optical theorem, the amplitude limit, and the manifestly local test. We find agreement among the different methods.

Abstract Trachoma, caused by ocular Chlamydia trachomatis infection, is targeted for global elimination as a public health problem by 2030. To provide evidence for use of antibodies to monitor C. trachomatis transmission, we collated IgG responses to Pgp3 antigen, PCR positivity, and clinical observations from 19,811 children aged 1–9 years in 14 populations. We demonstrate that age-seroprevalence curves consistently shift along a gradient of transmission intensity: rising steeply in populations with high levels of infection and active trachoma and becoming flat in populations near elimination. Seroprevalence (range: 0–54%) and seroconversion rates (range: 0–15 per 100 person-years) correlate with PCR prevalence (r: 0.87, 95% CI: 0.57, 0.97). A seroprevalence threshold of 13.5% (seroconversion rate 2.75 per 100 person-years) identifies clusters with any PCR-identified infection at high sensitivity ( >90%) and moderate specificity (69–75%). Antibody responses in young children provide a robust, generalizable approach to monitor population progress toward and beyond trachoma elimination.

Abstract Seroepidemiology, or measuring antibodies to pathogens to estimate population-level exposure, can provide useful public health data. The tests used, however, often lack sufficient validation data due to absence of a gold standard. For many pathogens, serum antibodies can be detected long after resolution of infection, but infection status is often used as a gold standard for antibody positivity. To ensure that recently developed antibody tests for seroepidemiology of Chlamydia trachomatis (Ct), the causative agent of urogenital chlamydia and the blinding eye disease trachoma, have high performance, we generated a chimeric antibody to the immunodominant Ct antigen Pgp3. Two clones were selected to evaluate the test performance of three assays to measure antibodies to Pgp3: multiplex bead assay (MBA), enzyme-linked immunosorbent assay (ELISA), and lateral flow assay (LFA). Overall, each assay demonstrated high accuracy and precision when tested using either clone, and the clones were stable when stored at − 20 °C and 4 °C for almost 2 years. The limit of detection was similar for MBA and LFA, but almost a log-fold higher (i.e. less sensitive) using ELISA. Overall, the chimeric antibodies represent stable control reagents for tests with robust performance and will facilitate deployment of these tests to other laboratories.

Internationally, lead agencies and consumer movements emphasise the need for high-level research participation in mental health. However, evidence suggests that people with lived experience tend to be recruited as subjects rather than as active agents in research, or are consulted in tokenistic ways. Although participatory research has the potential to rectify epistemic disparities, few studies have grappled with how to move from exclusion and tokenism to high-level research participation. This paper describes a qualitative co-evaluation of a co-produced model of research partnership, Raising the Bar , which involved deliberate establishment and facilitation of six participatory research teams, comprising 28 lived experience and ‘conventional' mental health researchers. Findings indicate that the theoretical elements of the model set the bar high from the outset, supporting research teams to address inconsistencies in knowledge about participation. It also provided researchers with the competencies and resources to undertake participatory research in egalitarian team structures, and to negotiate new forms of non-traditional research outputs - thereby challenging whom research might be for and how it might be made accessible. Finally, the model shifted collective meanings about research, lending credibility to participatory practices, which came to be seen as essential for meeting the needs of affected communities. Nonetheless, systemic barriers to participatory research remain, and need to be recognised and acted upon to promote a culture that supports high-level research participation.

Baseline mapping in the two major population centers of Kiribati showed that trachoma was a public health problem in need of programmatic interventions. After conducting two annual rounds of antibiotic mass drug administration (MDA), Kiribati undertook trachoma impact surveys in 2019, using standardized two-stage cluster surveys in the evaluation units of Kiritimati Island and Tarawa. In Kiritimati, 516 households were visited and in Tarawa, 772 households were visited. Nearly all households had a drinking water source and access to an improved latrine. The prevalence of trachomatous trichiasis remained above the elimination threshold (0.2% in ≥15-year-olds) and was virtually unchanged from baseline. The prevalence of trachomatous inflammation-follicular (TF) in 1-9-year-olds decreased by approximately 40% from baseline in both evaluation units but remained above the 5% TF prevalence threshold for stopping MDA. TF prevalence at impact survey was 11.5% in Kiritimati and 17.9% in Tarawa. Infection prevalence in 1-9-year-olds by PCR was 0.96% in Kiritimati and 3.3% in Tarawa. Using a multiplex bead assay to measure antibodies to the C. trachomatis antigen Pgp3, seroprevalence in 1-9-year-olds was 30.2% in Kiritimati and 31.4% in Tarawa. The seroconversion rate, in seroconversion events/100 children/year, was 9.0 in Kiritimati and 9.2 in Tarawa. Seroprevalence and seroconversion rates were both assessed by four different assays, with strong agreement between tests. These results show that, despite decreases in indicators associated with infection at impact survey, trachoma remains a public health problem in Kiribati, and provide additional information about changes in serological indicators after MDA.

This study focuses on the drying kinetics of cob and light-earth layers comprising a hybrid walling system. Volumetric water content sensors are immersed and placed at different positions on the walls of a building to measure the drying kinetics. In addition, an experimental analysis of the effect of temperature, relative humidity (RH), and wind velocity variations on thermal conductivity in a climatic chamber under winter and summer conditions was conducted. The analysis of samples in laboratory aims to investigate the hygrothermal properties of cob and light-earth materials, and their dependency on the aforementioned parameters. The in situ drying kinetics of both materials involves water content reduction and stabilization; however, in the laboratory, although the water content of materials decreases, the drying is incomplete. Which may be due to the limited wind speed. The hydrothermal properties show that open porosity affects water vapor permeability and modifies the RH of cob and light-earth. At 23 °C, when the relative humidity (RH) range was 10–30%, the absorbed water vapor of cob and light earth was 0–2%. However, when the RH is 40–90%, the absorbed water vapor of light earth (2–9%) exceeds that of cob (0.5–2%). Moreover, the response to relative humidity (RH) with regard to the mixing law of components and samples differs. The resistance factor to water vapor diffusion values for cob and light-earth are 12.9 and 8.2, respectively. In this study, the thermal conductivity measurements under summer and winter conditions provide the relationship between the thermal conductivity, density, and water content of cob and light-earth materials.

We report the serendipitous discovery of a bow-shock nebula around the cataclysmic variable (CV) SY Cancri. In addition, SY Cnc lies near the edge of a faint H α -emitting nebula with a diameter of about $15^{\prime} $ . The orientation of the bow shock is consistent with the direction of SY Cnc’s proper motion. Nebulae are extremely rare around CVs, apart from those known to have undergone classical-nova (CN) outbursts; bow shocks and off-center nebulae are even more unusual. Nevertheless, the properties of SY Cnc and its nebulosity are strikingly similar to those of V341 Ara, another CV that is also associated with a bow shock and is likewise off-center with respect to its faint H α nebula. Both stars are binaries with optically thick accretion disks, belonging to the classes of Z Cam CVs or nova-like variables. We discuss three scenarios to explain their properties. They may have resulted from chance encounters with interstellar gas clouds, with the stars leaving in their wakes material that is recombining after being photoionized by ultraviolet radiation from the CVs. Alternatively, the large nebulae could be ejecta from unobserved CN outbursts in the recent past, which have been decelerated through collisions with the interstellar medium (ISM), while the stars continue to snowplow through the gas. Or the faint H α nebulae may be ambient ISM that was flash-ionized by a CN outburst in the past and is now recombining.

The population of developed nations spends a significant amount of time indoors, and the implications of poor indoor air quality (IAQ) on human health are substantial. Many premature deaths attributed to exposure to indoor air pollutants result from diseases exacerbated by poor indoor air. CO2, one of these pollutants, is the most prevalent and often serves as an indicator of IAQ. Indoor CO2 concentrations can be significantly higher than outdoor levels due to human respiration and activity. The primary objective of this research was to numerically investigate the indoor relative humidity and CO2 in cob buildings through the CobBauge prototype, particularly during the first months following the building delivery. Both in situ experimental studies and numerical predictions using an artificial neural network were conducted for this purpose. The study presented the use of a piecewise autoregressive exogenous model (PWARX) for indoor relative humidity (RH) and CO2 content in a building constructed with a double walling system consisting of cob and light earth. The model was validated using experimental data collected over a 27-day period, during which indoor RH and CO2 levels were measured alongside external conditions. The results indicate that the PWARX model accurately predicted RH levels and categorized them into distinct states based on moisture content within materials and external conditions. However, while the model accurately predicted indoor CO2 levels, it faced challenges in finely classifying them due to the complex interplay of factors influencing CO2 levels in indoor environments.

Little is known about enteropathogen seroepidemiology among children in low-resource settings. We measured serological IgG responses to eight enteropathogens (Giardia intestinalis, Cryptosporidium parvum, Entamoeba histolytica, Salmonella enterica, enterotoxigenic Escherichia coli, Vibrio cholerae, Campylobacter jejuni, norovirus) in cohorts from Haiti, Kenya, and Tanzania. We studied antibody dynamics and force of infection across pathogens and cohorts. Enteropathogens shared common seroepidemiologic features that enabled between-pathogen comparisons of transmission. Overall, exposure was intense: for most pathogens the window of primary infection was

Among the student ideas about forces discussed in the literature, perhaps the most commonly reported is the notion of an impetus force, or the "belief that there is a force inside a moving object that keeps it going and causes it to have some speed." For example, Clement asked university students taking introductory mechanics to draw a free-body diagram for a coin that has been tossed upward. He found that students often drew an arrow in the direction of the coin's motion, at a point midway between the initial toss and the turnaround point, sometimes providing reasoning that suggested that the arrow corresponds to a "force from your hand" or the "force of the throw." Clement interpreted these responses as indicating that "student[s] may believe that continuing motion implies the presence of a continuing force in the same direction, as a necessary cause of the motion." As another example, in a study conducted with undergraduate students at Johns Hopkins University, McCloskey, Caramazza, and Green asked students to draw the path a ball will follow after it exits the curved tubes pictured in Fig. 1. The authors found that students often drew curved trajectories for the ball exiting each tube, and they coined the term "curvilinear impetus principle" to describe students' reasoning. They write that students reasoned as though "an object constrained to move in a curved path acquires a curvilinear impetus that causes it to continue in a curved trajectory for some time after the constraints on its motion are removed."

Resources theory assumes that resource activation is context sensitive, and that an important dimension of context is the question students are answering. The context sensitivity of resource activation has been demonstrated empirically by case studies that show students using different resources to answer questions that are similar in focus. In this paper, we further substantiate and add specificity to the field's understanding of the context sensitivity of resource use by demonstrating a pattern in resource activation for questions about mechanical pulse propagation, superposition, and reflection. In particular, our analysis shows a pattern in the kinds of resources students use to answer different "styles" of questions about the same physics topic. Questions that ask for a prediction tend to elicit rules or procedures, while questions that ask students to explain an observation elicit these "plus" ideas about force, energy, and motion. Our results call both researchers' and instructors' attention to the style of question that they ask and the impact it has on the resources commonly cued for students.

Existing research identifying common student ideas about forces focuses on students' misunderstandings, misconceptions, and difficulties. In this paper, we characterize student thinking in terms of resources, framing student thinking as continuous with formal physics. Based on our analysis of 2048 written responses to conceptual questions, we identify six common conceptual resources for understanding forces. We document context-sensitive patterns in resource activation, and we discuss limitations of our research based on the demographics of our sample.

Knowledge of indoor air quality (IAQ) in cob buildings during the first few months following their delivery is of vital importance in preventing occupants’ health problems. The present research focuses on evaluating IAQ in cob buildings through a prototype built in Normandy, France. To achieve this, the prototype was equipped with a set of sensors to monitor various parameters that determine indoor and outdoor air quality. These parameters include relative humidity (RH), carbon dioxide (CO2), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM1 and PM10), and volatile organic compounds (VOCs). The obtained experimental results indicate that, overall, there is good indoor air quality in the prototype building. However, there are some noteworthy findings, including high indoor RH and occasional spikes in CO2, PM1, PM10, and VOCs concentrations. The high RH is believed to be a result of the ongoing drying process of the cob walls, while the peaks in pollutants are likely to be attributed to human presence and the earthen floor deterioration. To ensure consistent good air quality, this study recommends the use of a properly sized Controlled Mechanical Ventilation system. Additionally, this study explored IAQ in the cob building from a numerical perspective. A Long Short-Term Memory (LSTM) model was developed and trained to predict pollutant concentrations inside the building. A validation test was conducted on the CO2 concentration data collected on-site, and the results indicated that the LSTM model has accurately predicted the evolution of CO2 concentration within the prototype building over an extended period.

In a randomized placebo-controlled trial in rural Niger, biannual azithromycin distribution to children 1-59 months reduced all-cause mortality. Based on serology, Arzika et al. here report a reduction of Campylobacter infection, supporting one mechanism for the intervention’s impact on mortality.