33659 research outputs found
Sort by
The complex associations between adiposity, fitness, mental wellbeing and neurocognitive function after exercise: A randomized crossover trial in preadolescent children
No full textThe aim of the present study was to examine the associations of adiposity and fitness on the preadolescent brain\u27s response to acute exercise. In a sample of 58 children (ages 8–10; 19 females), demographic measures of age, sex, IQ, puberty, and socioeconomic status were considered. Children participated in a randomized crossover study, whereby they completed two different interventions; seated rest or treadmill walking, counterbalanced across participants. Associations between adiposity measures (standardized body mass index [BMI-Z], whole body percent fat [%Fat], visceral adipose tissue [VAT]), cardiorespiratory fitness measures (VO2max and Fat-Free VO2) were assessed on self-reported measures of mental wellbeing, and cognitive performance (response accuracy, reaction time) and neuroelectric (P3 amplitude and latency) indices of a Go/NoGo task following both exercise and rest interventions. Higher adiposity (whole-body percent fat, BMI-Z) was associated with higher trait anxiety (P\u27s ≤ 0.05) and disordered eating (P\u27s ≤ 0.05) scores. Higher fitness (VO2max) was associated with lower childhood depression scores (P = 0.02). Regression analyses yielded specific post-exercise neurocognitive associations with adiposity-related (VAT, BMI-Z), and fitness-related (FF-VO2) outcomes, after controlling for post-rest neurocognitive outcomes. VAT was positively associated with post-exercise P3 ERP Latency for the Go task (P ≤ 0.001); BMI-Z was negatively associated with P3 ERP amplitudes for the Go task (P\u27s ≤ 0.005); FF-VO2 was negatively associated with P3 ERP latency for the Go/NoGo task (P\u27s ≤ 0.05), and positively associated with NoGo task accuracy (P ≤ 0.001). Overall, adiposity and fat-free fitness measures yield sensitive and differential associations with neurocognitive performance after exercise and after rest interventions
Fatigue Analysis of a Jacket-Supported Offshore Wind Turbine at Block Island Wind Farm
No full textOffshore wind-turbine (OWT) support structures are subjected to cyclic dynamic loads with variations in loadings from wind and waves as well as the rotation of blades throughout their lifetime. The magnitude and extent of the cyclic loading can create a fatigue limit state controlling the design of support structures. In this paper, the remaining fatigue life of the support structure for a GE Haliade 6 MW fixed-bottom jacket offshore wind turbine within the Block Island Wind Farm (BIWF) is assessed. The fatigue damage to the tower and the jacket support structure using stress time histories at instrumented and non-instrumented locations are processed. Two validated finite-element models are utilized for assessing the stress cycles. The modal expansion method and a simplified approach using static calculations of the responses are employed to estimate the stress at the non-instrumented locations—known as virtual sensors. It is found that the hotspots at the base of the tower have longer service lives than the jacket. The fatigue damage to the jacket leg joints is less than 20% and 40% of its fatigue capacity during the 25-year design lifetime of the BIWF OWT, using the modal expansion method and the simplified static approach, respectively
Silk in New England: From Sericulture to Status Symbol
Get PDFMadelyn Shaw is an independent curator and textile historian. She traced the rich legacy of silk in New England from its 17th-century origins to its rise as a driver of regional industry. The production of silk began with home-based sericulture in Virginia and Connecticut and later evolved into mill-based manufacturing. The 1830s saw a silk craze in New England that faded when a disease killed the mulberry trees whose leaves fed the silkworms. Later, imported raw silk from China became more affordable for the middle class, and American mills helped popularize silk garments. Although silk declined in the 20th century due to the war between China and Japan and the rise of synthetic alternatives like rayon, the silk industry’s impact on textile production in New England was considerable
Salvation and Scandal at Michigan’s House of David
No full textIn 1903, preachers Mary and Benjamin Purnell moved to Benton Harbor, Michigan, to found a commune called the House of David. Its members were Christian Israelites, who sought to assemble the remnants of the lost tribes of Israel in a new Jerusalem and believed this ingathering of 144,000 would never die. They relinquished all assets, practiced celibacy, and renounced meat, hair-cutting, and traditional family ties — in exchange for community, economic security, and the promise of immortality. The Israelites sought refuge from the abuses of industrial capitalism even as they embraced modern popular culture by running a successful amusement park, performing in the colony’s touring musical groups, and playing on barnstorming baseball teams. The commune thrived into the 1960s – and lingers on as a tiny remnant today — despite a steady stream of financial and sexual scandals, a torrent of litigation, and obsessive coverage in the press. It defied the odds to become one of the longest lasting intentional communities in United States history.
This talk – based on Evelyn Sterne’s forthcoming book (The House of David: Salvation, Scandal and Survival in a Modern American Commune, Oxford University Press, 2025) – analyzes why critics were determined to discredit the House of David and what that reveals about limits to religious toleration, and debates over what constituted “religion,” at a pivotal moment in U.S. history
Evaluation of Multimodal Analgesia Utilization in Patients Admitted to General Medicine at VA Providence Healthcare System with Acute Pain Receiving Oral Opioids
Get PDFPoster presented by Sydney Story, PharmD, at the 2024 American Society of Health-Systems Pharmacists Midyear Clinical Meeting
Ambient Temperature Phase Change Launcher
Get PDFThe Naval Undersea Warfare Center has presented a project to our group, Team 07, that studies the methodology of launch of an underwater payload using the phase change of an inert compound from liquid to gas. The designed system must use the energy generated from the phase change to push the payload through the water and away from its original source.
NUWC tasked the team with fulfilling several requirements through the course of the design process. This list included such parameters as the volume of liquid used to launch the payload must be less than one-quarter the volume of the launch cylinder, the acceleration of the payload must be under 8 g’s, and the payload length must be seven-times greater than its diameter. The team took the list of requirements and created engineering and customer requirements to apply to the conceptual designs. These designs were compared not only to one another, but also previous work to further derive potential ideas. The concepts that demonstrated the highest viability were put together into three distinct final designs that would be compared using modeling and testing.
During the fall semester a prototype of the final chosen design was created to test feasibility. The prototype was made primarily of PVC pipe and utilized manufactured carbon dioxide canisters to propel the payload. Data extraction and analysis were used to analyze the feasibility of the design and future changes that need to occur.
In the following spring semester the team used all the data collected to improve upon the prior design and manufacture a final prototype of the design. This design included a solenoid for remote launch, a galvanized steel launch tube to withstand the high pressure of the system, and a custom CO2 canister that eliminated the prior problems with head loss
Gas Turbine Tube Driver and Control System
Get PDFThis project, spearheaded by Team 21H under the guidance of Professor Nassersharif, and NASA, aims to design and develop an innovative turbine system for a Centrifugal Thermal Rocket (CNTR), capable of supporting a 420-day manned space mission. The primary objective was to create a gas turbine and control system that could spin the fuel cell at speeds ranging from 5000 to 7000 RPM, using hydrogen propellant as the working fluid, and withstand extreme temperature variations from the cold of space up to 5500 Kelvin. The team\u27s approach involved extensive research, design, and testing, with a focus on maximizing speed and selecting appropriate materials. The key to this project was the development of a prototype that could operate efficiently under dynamic fluid motion, and high rotation speeds. This involved creating CAD models of the moderator block as well as a turbine created around gas turbine theory. A 3D printed prototype was built for proof of concept, accompanied by CFD simulations and computational calculations to verify the design\u27s efficacy in terms of speed, thermodynamics, fluid dynamics, blade interaction, vibration, and pressure. The scalded model was placed into a wind tunnel where it was placed under conditions and asset to view its performance and have data collected.
Innovations in the project included conceptualizing a control system that allows for variable gas flow and turbine velocity, from zero to maximum. This was complemented by a backup system inspired by the NERVA design, featuring four fuel tanks for enhanced redundancy. The turbine\u27s design and functionality were tested in a wind tunnel, confirming its ability to achieve desired top speeds with minimal vibrations. As the project progresses, Team 21H will continue to refine and iterate our turbine design, focusing on the construction and assembly improvements. This approach ensures the turbine not only meets NASA\u27s stringent requirements for space missions but also advances the field of aerospace engineering through practical innovation and rigorous testing
A data-driven global flood forecasting system for medium to large rivers
No full textLosses from catastrophic floods are driving intense efforts to increase preparedness and improve response to disastrous flood events by providing early warnings. Yet accurate flood forecasting remains a challenge due to uncertainty in modeling, calibrating, and validating a useful early warning system. This paper presents the Requisitely Simple (ReqSim) flood forecasting system that includes key variables and processes of basin hydrology and atmospheric forcing in a data-driven modeling framework. The simplicity of the modeling structure and data requirements of the system allows for customization and implementation in any medium to large rain-fed river basin globally, provided there are water level or discharge measurements at the forecast locations. The proposed system\u27s efficacy is demonstrated in this paper through providing useful forecasts for various river basins around the world. This include 3–10-day forecasts for the Ganges and Brahmaputra rivers in South Asia, 2–3-day forecast for the Amur and Yangtze rivers in East Asia, 5–10-day forecasts for the Niger, Congo and Zambezi rivers in West and Central Africa, 6–8-day forecasts for the Danube River in Europe, 2–5-day forecasts for the Parana River in South America, and 2–7-day forecasts for the Mississippi, Missouri, Ohio, and Arkansas rivers in the USA. The study also quantifies the effect of basin size, topography, hydrometeorology, and river flow controls on forecast accuracy and lead times. Results indicate that ReqSim\u27s forecasts perform better in river systems with moderate slopes, high flow persistence, and less flow controls. The simple structure, minimal data requirements, ease of operation, and useful operational accuracy make ReqSim an attractive option for effective real-time flood forecasting in medium and large river basins worldwide
Meso-structural degradation and mechanical property evolution in cementitious mortars containing microencapsulated phase change materials under extended freeze-thaw cycles
No full textThis paper explores the influence of incorporating microencapsulated Phase Change Materials (MPCM) on the evolution of both mechanical behavior and meso-structural damage in mortars in response to prolonged freeze-thaw conditions, employing Differential Scanning Calorimetry (DSC) for thermal analysis, comprehensive mechanical performance experiments, and high-resolution X-ray Tomography (XRT) to assess internal damage evolution. The DSC results highlight the thermoregulatory effect of MPCM, which influences the performance of the mortars under freeze-thaw conditions. Mechanical experiments show a trade-off between initial strength and long-term durability, with MPCM-enhanced mortars demonstrating significantly reduced strength loss when exposed to extended freeze-thaw cycles compared to control mortars. XRT images further corroborate these outcomes, illustrating less pronounced meso-structural degradation in MPCM-containing samples when exposed to extended freeze-thaw cycles. Overall, the findings in this paper reveal that MPCM-infused mortars, particularly those with higher MPCM concentrations, exhibit significantly reduced internal damage and maintain better mechanical integrity compared to control samples. Collectively, these insights suggest that MPCM integration could be a pivotal strategy for designing more resilient and durable cementitious composites, paving the way for future advancements in construction practices tailored to withstand the challenges of freeze-thaw conditions