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Ultrahigh-performance concrete (UHPC) is a new class of concrete with far superior mechanical and durability properties compared to conventional concrete. Recently, its use has been growing in both civil and architectural applications, especially in the precast industry. This paper presents the application of UHPC to the production of precast concrete sandwich wall panels commonly used in Northern regions and known as insulated wall panels. Using UHPC in the panel wythes allows for a significant reduction in wythe thickness and, consequently, panel weight, in addition to the elimination of longitudinal and transverse reinforcement, which simplifies production. In this study, four 2.44 m × 1.22 m × 203 mm composite UHPC sandwich wall panels were fabricated by a local precast producer using a nonproprietary UHPC mixture. Panels were tested in flexure to evaluate the degree of composite action when wythe thickness of 32 mm and glass fiber–reinforced polymer (GFRP) shear connectors are used. These panels do not contain any conventional rebars or prestressing strands as they are fully dependent on the presence of random steel fibers in UHPC to provide the tensile resistance. Test results have shown that this new system can achieve a flexural capacity of 92% of that of a fully composite panel while being more flexible and lighter than conventional concrete sandwich wall panels. The composite UHPC sandwich wall panels have a great potential in architectural and structural applications, such as exterior load-bearing walls and cladding panels. This paper investigates the structural behavior of a new system of sandwich wall panels utilizing reduced wythe thicknesses made of ultrahigh-performance concrete (UHPC) and achieving high degree of composite action. Structural performance and production efficiency of this system can have significant impacts on energy-efficient building construction. This new system can achieve a degree of composite action up to 92%, which makes the design efficient for large cladding panels and load bearing exterior walls. A design example is presented comparing a conventional concrete sandwich wall panel made of two 76-mm-thick concrete wythes and 51-mm-thick insulation to a UHPC panel with the same overall thickness of 203 mm but with 32-mm-thick concrete wythes and 140-mm-thick insulation. Both panels are 2.44-m wide and 9.14-m tall and subjected to unfactored wind pressure of 1.44-kPa, which is considerably higher than the typical values used in wall design for midwest states. The significant increase in the insulation thickness of the UHPC panel results in significantly less weight and higher R-value than those of the conventional concrete panel. In addition, the UHPC panel does not have either longitudinal prestressing strands or transverse reinforcing bars, which simplifies panel fabrication. [ABSTRACT FROM AUTHOR]

As previous research has observed, medical students and physicians alike confront vast amounts of knowledge in their education and practice, such that no one clinician can know everything there is to know about biomedicine. Even before clerkships, medical students learn to cope with this impossibility by prioritizing certain information based on its perceived utility for exams and clinical practice. Many factors can shape this process, including teamwork, wherein individual medical students rely on one another to address gaps in knowledge at the level of the group. This paper will draw on qualitative data from two allopathic medical schools in the American Midwest to demonstrate that peer-to-peer learning, a widely utilized pedagogical modality in North American medical schools, is amongst the earliest places where future physicians learn how to rely on their peers in the profession as they make choices about what to know and what not to know about biomedicine: cultivating a culture of "intraprofessionalism" between students with different knowledges and values, as they prepare to enter the same profession. The paper will also consider how differences in the student populations at two field sites impact intraprofessional development. Drawing on scholarship of peer-based learning strategies and the sociology and anthropology of medical education, the authors argue that peer-to-peer learning is a key site in the professional socialization of medical students toward the effective management of medical knowledge. [ABSTRACT FROM AUTHOR]

Zen Buddhists take the bodhisattva vow to save all beings. At Clouds in Water Zen Center in St. Paul, Minnesota, this means engaging in specific activities geared toward eliminating social and systemic injustice while also working to eliminate the causes and conditions of suffering within oneself. At Ryumonji Zen Monastery in Dorchester, Iowa, the bodhisattva vow to save all beings means to wholeheartedly engage in everyday activities, such as doing the dishes, without attachment or aversion; Ryumonji sees no need to engage specifically in socio-political activities. Clouds has a robust program of workshops and retreats on social engagement and participates locally in socio-political activism as part of its Buddhist practice. On the contrary, Ryumonji does not have a distinct program for social engagement but contextualizes every activity as already having a socio-political effect. Ryumonji Zen Monastery and Clouds in Water Zen Center are less than a hundred miles away in the American Midwest and both follow the same Sōtō Zen lineage of the Japanese priest Dainin Katagiri. Yet, they offer two different ways of responding to the world’s suffering. This paper analyzes the differing views and practices for social engagement at Ryumonji and Clouds, revealing differing interpretations of the central Buddhist teachings of interdependence, the bodhisattva vow, and the inseparability of individual and social liberation. It situates the divergent interpretations in their respective rural and urban contexts, regional Midwestern context, and within the larger context of development of Buddhism in America. [ABSTRACT FROM AUTHOR]

Background: While the effectiveness of tutoring‐style videos has been reported in previous studies conducted in laboratories, how these types of videos facilitate students' learning experiences and achievement has not been much explored in prior studies, which prevents discussion on how to design such tutoring‐style videos. Objectives: In this study, we addressed the limitations reported in studies conducted in authentic classes and attempted to explore students' learning patterns and experiences with tutoring‐style videos involving interactions between the instructor and agents. In addition, we attempted to reveal what instructional strategies can be used in tutoring‐style videos to enhance students' engagement and achievement. Methods: The study took place in an undergraduate introductory biology class offered at a university located in the Midwest of the United States. The same instructor taught two sections of this course which lasted for 15 weeks during a Spring semester. The two sections were randomly assigned to an experimental group in which participants watched tutoring‐style videos and a control group with participants watching traditional videos. The experiment was administered in a module lasting two and a half weeks focused on microbiology. Surveys and tests were conducted to determine whether the tutoring‐style videos had a positive impact on student engagement and achievement. In addition, a video content analysis was carried out to elicit insights on how to design effective tutoring‐style videos. Results: For students' emotional engagement and perceived usefulness, no significant difference was found between the two groups, even though the descriptive statistics indicated slightly higher scores from the experimental group than the control group on both subscales. In terms of achievement, the participants reported significantly more learned concepts from watching rich‐interactions in the tutoring‐style videos than the participants in the control group; and they also reported a significantly smaller number of learned concepts from watching one‐interactions in the videos than the control group participants. We also found that instruction in the tutoring‐style videos used effective strategies for facilitating students' participation and cognitive processing. Conclusions: Our findings indicate that tutoring‐style videos can be effective learning materials by allowing students to engage in interactions between instructors and agents in the videos. The more instructional strategies used to facilitate the interactions between the instructor and the agents, the higher engagement can be expected from viewers. Our study would inform the design and development of effective tutoring‐style videos. Lay Description: What is already known about this topic: One‐on‐one tutoring is the gold standard in teaching.Tutoring‐style videos are found to be effective in teaching as well. What this paper adds: Tutoring‐style videos that film rich interactions lead to better learning.Tutoring‐style videos that film limited interactions are ineffective.Students who see agents in tutoring‐style videos as helpful perform better. Implications for practice and/or policy: Tutoring‐style videos should film rich interactions of tutoring sessions.Strategies should be used in videos to facilitate perceived agents' usefulness.Tutoring sessions filmed in videos should encourage a participatory atmosphere. [ABSTRACT FROM AUTHOR]

Background or Context: Dual language education aims to foster the development of bilingualism, biliteracy, sociocultural competence, and academic skills in all school subjects. Early correlational research suggests that participation in dual language education is associated with higher achievement. Recent studies leveraged more comprehensive sets of baseline characteristics and found that dual language students improved their achievement status more than other students. A major limitation to these studies is their lack of ability to model within-student growth. Thus, we lack evidence on the relationship between dual language education and growth trajectories within and across grades. Purpose: This paper reports academic achievement and growth in grades 2 through 8 for Hispanic participants and nonparticipants of a Spanish–English dual language program. It extends the literature by providing novel evidence on seasonal patterns of learning for multilingual students across the elementary and middle grades. Research Design: Applying a piecewise multilevel model to rich assessment data on a large sample of Hispanic students in a district in the Midwest, I compare the math and English reading growth rates of participants to nonparticipants of a dual language (DL) program. By separately specifying growth terms for each school year and summer, I test whether any differences in growth rates between DL and non-DL students expand, stay the same, or diminish across grade levels. Conclusion: Dual language participants started second grade with lower achievement than nonparticipants. In math, dual language participants grew more than nonparticipants during each year in grades 2 to 5 but lost more learning during summers. In English reading, dual language participants grew more during some school years. These findings suggest summer learning opportunities are crucial for addressing achievement disparities. [ABSTRACT FROM AUTHOR]

College students have high rates of post-traumatic stress disorder (PTSD) symptoms as well as high rates of sexual assault. What is less clear, however, is whether different sexual assault types (e.g. coercive, physically forced, and incapacitation) are associated with greater PTSD symptoms. Moreover, understanding early familial and mental health histories of college students is important for explaining PTSD symptoms. As such, we use a social stress framework to examine the relationships between early familial risk (i.e. child abuse, perceived maternal rejection), borderline personality (BP) symptoms, and three sexual assault types with PTSD symptoms among college students. A total of 783 undergraduate students (65.4% female) completed paper and pencil surveys in fall 2019 and spring 2020 at a large public university. Results revealed that females were more likely to experience child sexual abuse and all three forms of sexual assault, while males experienced higher rates of child physical abuse. OLS regression results showed positive associations between child sexual abuse, perceived maternal rejection, BP symptoms and all three types of sexual assault with PTSD symptoms. Females also experienced more PTSD symptoms compared to males. Findings have implications for targeted interventions to improve mental health outcomes. [ABSTRACT FROM AUTHOR]

• Integrating ESSD into the socio-ecological systems framework. • Building a Socio-ecological indicators framework to analyze the drivers of ESSD. • The surging demand for public-good contributed to a significant increase in ESV. • The maximum explanatory power of factor interaction for ESV was 99%. The balance between the supply and demand of ecosystem services (ESSD) is important for sustainable regional development. The hilly regions of south China have rich natural resources and are rapidly being urbanized, which significantly impacts sustainable development in the region. Therefore, how to analyze ESSD from the perspective of social ecology is imperative. Ganzhou region, which is a typical hilly region in southern China, as an example, this paper creatively integrated ESSD into the social-ecological system (SES) framework, analyzed the spatial and temporal changes of ESSD in 2005, 2010, 2015, and 2020, and constructed a system of indicators from the SES, and analyzed the driving factors of ESSD, so as to provide a reference for balancing ESSD. Based on the classical SES framework proposed by Ostrom, this study first analyses the social-ecological system profile of the Ganzhou region at the macro-scale and constructs an SES indicator system. The innovation of combining the SES framework and ecosystem services lies in integrating the social and ecosystem perspectives and merging these two concepts to understand better and manage the relationship between humans and the natural environment. It provides a comprehensive analytical approach and decision support tool for achieving sustainable development. Our results demonstrate that: (1) From 2005 to 2020, ecosystem services in the study area were highly valued, lower areas had homogeneous distribution characteristics, total demand displayed spatial differentiation, there were high-value areas in the midwest, and low-value areas were concentrated in the region's boundary. (2) There are obvious supply and demand deficits in the southeast and east of the study area, while supply–demand is equal in the north and supply exceeds demand in other regions. From 2005 to 2020, the overall coupling coordination degree of ESSD in the study area was lower than 0.5, indicating a mild to moderate imbalance. (3) The supply of ecosystem services (ESS) was primarily driven by carbon storage, habitat quality, and water yield, while the demand was primarily driven by forest and grassland areas. Factors related to the ecosystem, resource unit, resource system, social system, governance system, and actor all have experienced two-factor interactions, which can explain up to 99% of ESSD. Based on the SES framework, this paper studies the relationship between ESSD in typical areas of the southern hills to provide a reference for research on ESSD in relevant areas and provide a scientific basis for the Chinese government to evaluate ecological protections and improve compensation policies, which is important for ensuring China's ecological security. [ABSTRACT FROM AUTHOR]

Future changes in land use/land cover (LULC) and climate (CC) affect watershed hydrology. Despite past research on estimating such changes, studies on the impacts of both these nonstationary stressors on urban watersheds have been limited. Urban watersheds have several important details such as hydraulic infrastructure that call for fine-scale models to predict the impacts of LULC and CC on watershed hydrology. In this paper, a fine-scale hydrologic model—Personal Computer Storm Water Management Model (PCSWMM)—was applied to predict the individual and joint impacts of LULC changes and CC on surface runoff attributes (peak and volume) in 3800 urban subwatersheds in Midwest Florida. The subwatersheds a range of characteristics in terms of drainage area, surface imperviousness, ground slope and LULC distribution. The PCSWMM also represented several hydraulic structures (e.g., ponds and pipes) across the subwatersheds. We analyzed changes in the runoff attributes to determine which stressor is most responsible for the changes and what subwatersheds are mostly sensitive to such changes. Six 24-h design rainfall events (5- to 200-year recurrence intervals) were studied under historical (2010) and future (year 2070) climate and LULC. We evaluated the response of the subwatersheds in terms of runoff peak and volume to the design rainfall events using the PCSWMM. The results indicated that, overall, CC has a greater impact on the runoff attributes than LULC change. We also found that LULC and climate induced changes in runoff are generally more pronounced in greater recurrence intervals and subwatersheds with smaller drainage areas and milder slopes. However, no relationship was found between the changes in runoff and original subwatershed imperviousness; this can be due to the small increase in urban land cover projected for the study area. This research helps urban planners and floodplain managers identify the required strategies to protect urban watersheds against future LULC change and CC. [Display omitted] • Changes in runoff attributes due to CC and LULC change in 3800 urban watersheds. • Greater changes for runoff peak than volume. • Greater changes in both runoff attributes for milder slope and smaller watersheds. • Dominant impacts of CC over LULC change for both runoff attribute. [ABSTRACT FROM AUTHOR]

• An attempt is made towards treatment of urban runoff using tire derived aggregates. • Role of biofilms in TDA-based treatment systems was analyzed using batch studies. • Phosphorous concentration is reduced below USEPA recommended disposal limit. • TDA-based stormwater treatment systems can work roughly up to 8–9 years. • Biofilm was seen to limit the leaching of metals from tire-derived aggregates. The importance of biofilm in tire derived aggregates (TDA) based underground systems has been investigated in this paper, to assess the utilization of tire waste as a cost-effective and sustainable resource for stormwater treatment. The primary objective of this study is to look into the role of biofilms in preventing metal leaching from a TDA based stormwater treatment system and to estimate the life span of a TDA based stormwater treatment system. TDA subjected to different influents to promote or limit the growth of biofilms were analyzed for their leaching and adsorption potential for fifteen different metals through 72 flushes, which is representative of roughly 9 years of TDA exposure to storm events in the upper Midwest USA. Biofilm growth on a manufacturing byproduct (wire exposed-TDA) was higher than on the traditional TDA. The presence of biofilm on TDA had a minor impact on orthophosphate adsorption as observed in a previous study conducted by the authors. However, metals such as iron, zinc and copper, which were previously a concern, had substantially lower leaching into the stored runoff. In addition, the orthophosphate removal from runoff by TDA with a biofilm through 72 flushes indicates that TDA based underground systems can have orthophosphate removal life span beyond 8–9 years. Thus, TDA with biofilms in an underground storage/infiltration chamber has the potential to establish itself as a sustainable, cost-effective, and long life-span alternative for stormwater remediation of orthophosphate pollution without leaching of metals. [ABSTRACT FROM AUTHOR]

Effective ways to promote healthful food intake in rural areas are understudied. The paper evaluated whether a two-component, in-store intervention designed to encourage healthy food purchases was associated with improved healthfulness scores of food items purchased by shoppers in rural food deserts. One component introduced a point-of-sales label that assigned a single numerical score to each food item facilitating direct comparisons of the product's nutrition with those of other products shelved around it. The other component was a one-day nutrition education workshop promoted within the store. Interventions took place in 2015 at two stores in rural counties in the U.S. Midwest. Four stores in similar communities were selected as the control group. We applied a difference-in-difference model to estimate changes in the healthfulness of food items purchased attributable to the intervention among shoppers at the treatment stores (n = 486) and control stores (n = 10,759) using store transaction data. Healthfulness of food items was measured in terms of food scores published by the Environmental Working Group on a 1–10 scale. Both components had minimal impacts on the scores, although 0.2 and 0.1 points increases in the score per item and score per dollar were statistically significant at the 1% level respectively. A year after the intervention, these small effects of the intervention further diminished compared to the immediately after implementation. Results suggest the average effects of intervention across the study communities had limited practical significance but benefited some rural residents who were exposed to the intervention. [ABSTRACT FROM AUTHOR]