114 research outputs found
Proof Rolling of Foundation Soil and Prepared Subgrade During Construction
Proof rolling provides a method to examine the entire subgrade surface as a compliment to standard random acceptance testing. Proof rolling requires established criteria that account for the interplay of equipment parameters and soil characteristics, technique, and other specifics of the project to allow for proper interpretation. The researchers concluded that proof rolling is not appropriate for determining soil elastic properties, while it can reveal in situ strength properties. No information from state highway agencies (SHA) publications or interviews reports using proof rolling other than for the evaluation of the subgrade. Only eight SHA’s have notable specifications or other supporting documents containing significant guidance or criteria. The requirements provided for use of either of two equipment types—tandem-axle rear dump trucks and chariot-style rollers—and a range of evaluation criteria based on soil type and whether the project is new construction or re-construction. Recommendations provided fall within parameters practiced by states that have the most well-developed specifications and practices for proof rolling. The recommendations include: evaluation is of the subgrade only and the equipment shall be either a tandem-axle rear dump truck or a tri-axle rear dump truck (with raised third axle) loaded to a minimum gross weight of 20 tons. The chariot-style roller loaded to a minimum gross weight of 40 tons could be alternatively specified. The test shall be a single pass in each traffic lane with the passing criteria of a 1″ deflection for new construction and ½″ deflection for re-constructed or stabilized subgrade, as well as the absence of pumping and cracking
A Synthesis Study on Collecting, Managing, and Sharing Road Construction Asset Data
Accurate and complete construction records and as-built data are the key prerequisites to the effective management of transportation infrastructure assets throughout their life cycle. The construction phase is the best time to collect such data. Assets such as underground drainage and culverts are visible and physically accessible only during construction. For assets such as guardrails, signals, and pavement, it is safer and more efficient to collect data during construction than after construction when the road segment is open to traffic.
The purpose of this project was to conduct a synthesis study to 1) assess the current status at INDOT regarding the collection of asset data during the construction phase and the use of such data in the operation and maintenance (O&M) phase, and 2) develop a framework for INDOT to leverage the construction inspection and documentation process to collect data for assets. Data needs during O&M were identified through rounds of meetings with relevant INDOT business units. The current practice in construction documentation was investigated in detail. A survey of state highway agencies (SHAs) was conducted to assess the state-of-the-practice.
A practical framework was developed to leverage the construction inspection and documentation practice to collect asset data that are needed in O&M. The framework uses specific pay items—construction activities that result in physical structures—as the bridge to connect plan assets (i.e. physical structures specified in the design documents) to their corresponding counterparts in the asset management systems. The framework is composed of 1) a data needs component for determining the information requirements from the O&M perspective, 2) a construction documentation module, and 3) a mapping mechanism to link data items to be collected during the construction documentation to data items in the asset management systems. The mapping mechanism was tested and validated using four priority asset classes—underdrains, guardrails, attenuators, and small culverts—from an INDOT construction project. The testing results show that the newly developed framework is viable and solid to collect asset data during the construction phase for O&M use in the future, without adding extra workload to construction crews. The framework can reduce/eliminate the duplicate data collection efforts at INDOT, leading to savings and efficiency gains in the long term
Video: No, You Can’t Touch My Hair: The Importance, Necessity, and Controversy of the CROWN Act
The Black Law Students Association welcomes you to our Fall 2020 panel event, which focuses on the 2019 CROWN Act. The CROWN Act, which stands for “Creating a Respectful and Open World for Natural Hair,” is a law that prohibits race-based hair discrimination, which is the denial of employment and educational opportunities because of hair texture or protective hairstyles including braids, locs, twists or bantu knots.This panel focuses on the legal perspective from different vantage points. Attendees will learn more about the Act, how it was handled, and the current political climate surrounding the Act. National CROWN Act and Dove Research Study Full details on panelists and presenters here: https://bit.ly/CROWN_Ac
The future of diets and hunger in South East Asia under climate change and alternative investment scenarios
Despite enjoying strong economic growth in the last few decades, Southeast Asia still faces challenges to food security, with high levels of stunting across countries in the region. Agricultural production is likely to see large impacts from climate change, including sea-level rise, droughts, and floods. The climate threat compounds pressures onto the food systems coming from the rapid demographic and income trends. Population across the region may grow by 25% between 2010 and 2050, and average income per capita may see a fourfold increase in the same period. In absence of climate impacts, growth in agricultural productivity is estimated to bring about an increase in production of over 50% between 2020 and 2050, with positive effects on the availability of kilocalories, and increased consumption of animal products. However, the projected climate impacts are expected to hit most of the crops in the region, especially cereals. Per capita income in 2050 may be negatively affected compared to a scenario without climate shocks. The resulting decrease in total calories availability translates into an increase in population at risk of hunger across the region and by country. We show that enhanced investments in public international agricultural R&D have the potential to improve yields despite the long-term negative effects of climate shocks, and when combined with increased research efficiency they may even offset climate impacts on food security across the region
Meta-analysis of genome-wide association studies of asthma in ethnically diverse North American populations.
Asthma is a common disease with a complex risk architecture including both genetic and environmental factors. We performed a meta-analysis of North American genome-wide association studies of asthma in 5,416 individuals with asthma (cases) including individuals of European American, African American or African Caribbean, and Latino ancestry, with replication in an additional 12,649 individuals from the same ethnic groups. We identified five susceptibility loci. Four were at previously reported loci on 17q21, near IL1RL1, TSLP and IL33, but we report for the first time, to our knowledge, that these loci are associated with asthma risk in three ethnic groups. In addition, we identified a new asthma susceptibility locus at PYHIN1, with the association being specific to individuals of African descent (P = 3.9 Ă— 10(-9)). These results suggest that some asthma susceptibility loci are robust to differences in ancestry when sufficiently large samples sizes are investigated, and that ancestry-specific associations also contribute to the complex genetic architecture of asthma
Validation of the Tetracycline Regulatable Gene Expression System for the Study of the Pathogenesis of Infectious Disease
Understanding the pathogenesis of infectious disease requires the examination and successful integration of parameters related to both microbial virulence and host responses. As a practical and powerful method to control microbial gene expression, including in vivo, the tetracycline-regulatable system has recently gained the favor of many investigative groups. However, some immunomodulatory effects of the tetracyclines, including doxycycline, could potentially limit its use to evaluate host responses during infection. Here we have used a well-established murine model of disseminated candidiasis, which is highly dependent on both the virulence displayed by the fungal cells and on the host immune status, to validate the use of this system. We demonstrate that the pathogenesis of the wild type C. albicans CAF2-1 strain, which does not contain any tet-regulatable element, is not affected by the presence of doxycycline. Moreover levels of key cytokines, chemokines and many other biomarkers, as determined by multi-analyte profiling, remain essentially unaltered by the presence of the antibiotic during infection. Our results indicate that the levels of doxycycline needed to control the tetracycline regulatable promoter gene expression system have no detectable effect on global host responses during candidiasis. Because tet-regulatable systems are now being increasingly used in a variety of pathogenic microorganisms, these observations have wide implications in the field of infectious diseases
Exploring African lion (Panthera leo) behavioural phenotypes: individual differences and correlations between sociality, boldness and behaviour
Psychosocial factors and early childhood caries among low-income African–American children in Detroit
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75540/1/j.1600-0528.2006.00352.x.pd
Agricultural Investments and Hunger in Africa Modelling Potential Contributions to SDG 2 - Zero Hunger
We use IFPRI’s IMPACT framework of linked biophysical and structural economic models to examine developments in global agricultural production systems, climate change, and food security. Building on related work on how increased investment in agricultural research, resource management, and infrastructure can address the challenges of meeting future food demand, we explore the costs and implications of these investments for reducing hunger in Africa by 2030. This analysis is coupled with a new investment estimation model, based on the perpetual inventory methodology (PIM), which allows for a better assessment of the costs of achieving projected agricultural improvements. We find that climate change will continue to slow projected reductions in hunger in the coming decades—increasing the number of people
at risk of hunger in 2030 by 16 million in Africa compared to a scenario without climate change. Investments to increase agricultural productivity can offset the adverse impacts of climate change and help reduce the share of people at risk of hunger in 2030 to five percent or less in Northern, Western, and Southern Africa, but the share is projected to remain at ten percent or more in Eastern and Central Africa. Investments in Africa to achieve these results are estimated to cost about 15 billion USD per year between 2015 and 2030, as part of a larger package of investments costing around 52 billion USD in developing countries
The International HapMap Project
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62838/1/nature02168.pd
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