Abstract Altered flow fields around submarine pipelines cause sediment scour beneath them, and the changing sediment profile is likely to feed back to fluid fields. However, the feedback mechanisms during and after the scour process as well as its impacts on hydrodynamic forcing on the pipeline remain unclear. This work applies two-dimensional fluid–sediment coupled modeling based on computational fluid dynamics (CFD) to study hydrodynamic coefficients of submarine pipelines, vortex shedding, and scour profiles at high Reynolds number. Results indicate that vortex shedding is dominant on the upper side of the pipeline at high flow velocities, while vortices on the underside gradually dissipate due to sediment accumulation downstream of the pipeline. This asymmetric vortex shedding leads to a net downward lifting force on the pipeline, resulting in negative lifting coefficients. Furthermore, scour initiated at high flow velocities can lead to sustained vortex shedding that imposes dynamic loading on the pipeline even under subsequently moderate flow conditions.
One in 12 children in the United States is diagnosed with asthma, making it a leading chronic health condition among school-aged youth. Poorly controlled symptoms can negatively impact children's social, emotional, and academic functioning. Given the central role of schools in children's daily lives, school-based supports and policies are critical for asthma management. This study surveyed 574 elementary and middle school teachers in Georgia and Kentucky regarding their perceptions of asthma-related medication policies, support plans (e.g., AAPs, 504 plans, IEPs), and student outcomes. Most teachers believed students were medically supported and had well-controlled symptoms, though many were unsure whether students had individualized plans. Teacher awareness of medication self-carry laws was linked with more positive perceptions of student academic performance. Findings highlight the need for greater teacher awareness and transparency to better support students with asthma in schools. Further, school psychologists can assist in supporting asthma management by facilitating interprofessional communication about individualized asthma plans and strengthening opportunities for medication administration in schools to better support symptom control to prompt better academic outcomes for youth with asthma.
This study investigates the efficacy of biochar derived from Southern Yellow Pine for the removal of polystyrene (PS) microplastics (0.2 µm) from aqueous solutions. Raw biochar was produced via carbonization and subsequently activated using CO2 at temperatures ranging from 550 to 850°C for activation times of 1–4 h, and was sieved into uniform-sized adsorbents between 300 and 425 μm. The effects of these activation parameters on the biochar's physicochemical properties and microplastic adsorption performance were systematically evaluated. Surface characterization through N2 adsorption, ultimate and proximate analyses, and FTIR revealed that activation significantly enhanced the specific surface area and porosity. The Brunauer–Emmett–Teller (BET) surface area increased from 235.6 m2/g for raw biochar to a maximum of 600.2 m2/g for biochar activated at 850°C for 1h. Batch adsorption experiments demonstrated a strong correlation between surface area and adsorption capacity. The biochar activated at 850°C exhibited the highest microplastic removal efficiency of 99
Outdoor play offers unique opportunities, making it critical to young children’s health and development. Yet many of today’s children spend very little time outdoors. Given the significant number of American children aged 3 to 5 who attend center-based early education programs, preschool teachers are uniquely positioned to promote the importance of outdoor play and facilitate young children’s interaction with the natural world. This study was designed to gain a deeper understanding of preschool teachers’ cognition about outdoor play. We collected data through an open-ended questionnaire from Montessori (n = 4), nature-based (n = 4), and public (n = 4) preschool teachers. Data revealed seven themes. Overall, teachers were knowledgeable about outdoor play and believed that it is connected to learning in a variety of domains. Teachers also supported interaction with nature and natural elements. Small subcategories were present between the types of early childhood programs and their relationship to outdoor play.
Household wealth from the stock market is unevenly concentrated among higher-income groups, and its distribution may be affected by stock market volatility. This paper investigates the relationship between stock market volatility and consumer spending through the lens of wealth distribution, with particular attention to different monetary policy environments. Using quarterly U.S. data from 1989 to 2024 within a state-dependent econometric framework, the study finds that stock market volatility significantly increases wealth inequality and lowers real per capita spending on durable goods, nondurable goods, and services during periods of easy monetary policy. Conversely, no significant effects are found under tight monetary policy, highlighting the state-dependent nature of the volatility-consumption relationship. This state dependency indicates a nonlinear dynamic relationship between stock market volatility and consumer spending. Additionally, results show that stock market volatility has a temporary effect on economic uncertainty and a smaller impact on consumption behavior than consumer sentiment. Policy recommendations include stabilization of stock market volatility and implementing confidence-building measures to sustain consumer spending and promote steady economic growth.
