121 research outputs found

    Proof Rolling of Foundation Soil and Prepared Subgrade During Construction

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    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

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    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

    The Effect of Workplace Bullying and Organizational Support on Health and Organizational Outcomes

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    We examined support systems on the health of those bullied at work. Our findings showed that bullied victims experience more stress, worse health, less satisfaction, and higher intentions to leave while organizational support systems help to minimize this effect of bullying on victims

    Seasonal forage quality of rangelands across Kansas

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    The K-State Research and Extension Forage Task Force surveyed Kansas rangelands during the course of seasonal changes to enable producers and managers to better estimate the feed value of their pasture forage during particular times of the year. Kansas’ two distinct rangeland vegetation types, shortgrass and tallgrass prairie, were evaluated. Forage samples were collected monthly from two rangeland sites in each of 10 Kansas counties. Tallgrass vegetation was lowest in acid detergent fiber (ADF) and greatest in crude protein (CP) from May to July, and rapidly increased in ADF and declined in CP the rest of the season. Shortgrass vegetation was also lower in ADF and greater in CP from May to July, but changed less from early summer to the winter than did tallgrass vegetation. Degradable intake protein (DIP) was greatest for tallgrass vegetation in May. Otherwise DIP was similar between tallgrass and shortgrass except in February and March when shortgrass had greater DIP. DIP was greatest in May and June for both vegetation types and gradually declined from June to December. Undegradable intake protein (UIP) values were greater for tallgrass vegetation than for shortgrass vegetation from May through July, but all other months were similar. Seasonal forage quality is different between and within rangeland vegetation types, and identification of dominant vegetation is a key determinant in choosing appropriate animal nutritional management strategies

    Discovery of a Disrupting Open Cluster Far into the Milky Way Halo: A Recent Star Formation Event in the Leading Arm of the Magellanic Stream?

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    We report the discovery of a young (tau similar to 117 Myr), low-mass (M similar to 1200 M.), metal-poor ([Fe H] similar to -1.14) stellar association at a heliocentric distance D approximate to 28.7 kpc, placing it far into the Milky Way (MW) halo. At its present Galactocentric position (R, z) similar to (23, 15) kpc, the association is (on the sky) near the leading arm of the gas stream emanating from the Magellanic Cloud system, but is located approximate to 60 degrees from the Large Magellanic Cloud center on the other side of the MW disk. If the cluster is colocated with H I gas in the stream, we directly measure the distance to the leading arm of the Magellanic stream. The measured distance is inconsistent with Magellanic stream model predictions that do not account for ram pressure and gas interaction with the MW disk. The estimated age of the cluster is consistent with the time of last passage of the leading arm gas through the Galactic midplane; we therefore speculate that this star formation event was triggered by its last disk midplane passage. Most details of this idea remain a puzzle: the Magellanic stream has low column density, the MW disk at large radii has low gas density, and the relative velocity of the leading arm and MW gas is large. However it formed, the discovery of a young stellar cluster in the MW halo presents an interesting opportunity for study. This cluster was discovered with Gaia astrometry and photometry alone, but follow-up DECam photometry was crucial for measuring its properties.National Science Foundation (NSF) [AST-1813881]; Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory (NOAO) [2018A-0251]; Center for Computational AstrophysicsThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

    Alterations in T and B cell function persist in convalescent COVID-19 patients

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    BackgroundEmerging studies indicate that some COVID-19 patients suffer from persistent symptoms including breathlessness and chronic fatigue; however the long-term immune response in these patients presently remains ill-defined.MethodsHere we describe the phenotypic and functional characteristics of B and T cells in hospitalised COVID-19 patients during acute disease and at 3-6 months of convalescence.FindingsWe report that the alterations in B cell subsets observed in acute COVID-19 patients were largely recovered in convalescent patients. In contrast, T cells from convalescent patients displayed continued alterations with persistence of a cytotoxic programme evident in CD8+ T cells as well as elevated production of type-1 cytokines and IL-17. Interestingly, B cells from patients with acute COVID-19 displayed an IL-6/IL-10 cytokine imbalance in response to toll-like receptor activation, skewed towards a pro-inflammatory phenotype. Whereas the frequency of IL-6+ B cells was restored in convalescent patients irrespective of clinical outcome, recovery of IL-10+ B cells was associated with resolution of lung pathology.ConclusionsOur data detail lymphocyte alterations in previously hospitalized COVID-19 patients up to 6 months following hospital discharge and identify 3 subgroups of convalescent patients based on distinct lymphocyte phenotypes, with one subgroup associated with poorer clinical outcome. We propose that alterations in B and T cell function following hospitalisation with COVID-19 could impact longer term immunity and contribute to some persistent symptoms observed in convalescent COVID-19 patients

    The acute mania of King George III: A computational linguistic analysis.

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    We used a computational linguistic approach, exploiting machine learning techniques, to examine the letters written by King George III during mentally healthy and apparently mentally ill periods of his life. The aims of the study were: first, to establish the existence of alterations in the King's written language at the onset of his first manic episode; and secondly to identify salient sources of variation contributing to the changes. Effects on language were sought in two control conditions (politically stressful vs. politically tranquil periods and seasonal variation). We found clear differences in the letter corpus, across a range of different features, in association with the onset of mental derangement, which were driven by a combination of linguistic and information theory features that appeared to be specific to the contrast between acute mania and mental stability. The paucity of existing data relevant to changes in written language in the presence of acute mania suggests that lexical, syntactic and stylometric descriptions of written discourse produced by a cohort of patients with a diagnosis of acute mania will be necessary to support the diagnosis independently and to look for other periods of mental illness of the course of the King's life, and in other historically significant figures with similarly large archives of handwritten documents

    Allelic diversity of S‑RNase alleles in diploid potato species

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    S-ribonucleases (S-RNases) control the pistil specificity of the self-incompatibility (SI) response in the genus Solanum and several other members of the Solanaceae. The nucleotide sequences of S-RNases corresponding to a large number of S-alleles or S-haplotypes have been characterised. However, surprisingly few S-RNase sequences are available for potato species. The identification of new S-alleles in diploid potato species is desirable as these stocks are important sources of traits such as biotic and abiotic resistance. S-RNase sequences are reported here from three distinct diploid types of potato: cultivated Solanum tuberosum Group Phureja, S. tuberosum Group Stenotomum, and the wild species Solanum okadae. Partial S-RNase sequences were obtained from pistil RNA by RT-PCR or 3’RACE (Rapid Amplification of cDNA Ends) using a degenerate primer. Full length sequences were obtained for two alleles by 5’RACE. Database searches with these sequences, identified sixteen S-RNases in total, all of which are novel. The sequence analysis revealed all the expected features of functional S-RNases. Phylogenetic analysis with selected published S-RNase and S-like-RNase sequences from the Solanaceae revealed extensive trans-generic evolution of the S-RNases and a clear distinction from S-like-RNases. Pollination tests were used to confirm the self-incompatibility status and cross-compatibility relationships of the S. okadae accessions. All the S. okadae accessions were found to be self-incompatible as expected with crosses amongst them exhibiting both cross-compatibility and semi-compatibility consistent with the S-genotypes determined from the S-RNase sequence data. The progeny analysis of four semi-compatible crosses examined by allele-specific PCR provided further confirmation that these are functional S-RNases

    The Rapid ASKAP Continuum Survey III: Spectra and Polarisation In Cutouts of Extragalactic Sources (SPICE-RACS) first data release

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    The Australian SKA Pathfinder (ASKAP) radio telescope has carried out a survey of the entire Southern Sky at 887.5 MHz. The wide area, high angular resolution, and broad bandwidth provided by the low-band Rapid ASKAP Continuum Survey (RACS-low) allow the production of a next-generation rotation measure (RM) grid across the entire Southern Sky. Here we introduce this project as Spectral and Polarisation in Cutouts of Extragalactic sources from RACS (SPICE-RACS). In our first data release, we image 30 RACS-low fields in Stokes I, Q, U at 25" angular resolution, across 744-1032 MHz with 1 MHz spectral resolution. Using a bespoke, highly parallelised, software pipeline we are able to rapidly process wide-area spectro-polarimetric ASKAP observations. Notably, we use `postage stamp' cutouts to assess the polarisation properties of 105912 radio components detected in total intensity. We find that our Stokes Q and U images have an rms noise of ∼ 80 μJy PSF-1, and our correction for instrumental polarisation leakage allows us to characterise components with ≳ 1% polarisation fraction over most of the field of view. We produce a broadband polarised radio component catalogue that contains 5818 RM measurements over an area of ∼ 1300 deg2 with an average error in RM of 1.6+1.1-1.0 rad m-2, and an average linear polarisation fraction 3.4+3.0-1.6%. We determine this subset of components using the conditions that the polarised signal-to-noise ratio is > 8, the polarisation fraction is above our estimated polarised leakage, and the Stokes I spectrum has a reliable model. Our catalogue provides an areal density of 4±2 RMs deg-2; an increase of ∼ 4 times over the previous state-of-the-art (Taylor, Stil, Sunstrum 2009, ApJ, 702, 1230). Meaning that, having used just 3% of the RACS-low sky area, we have produced the 3rd largest RM catalogue to date. This catalogue has broad applications for studying astrophysical magnetic fields; notably revealing remarkable structure in the Galactic RM sky. We will explore this Galactic structure in a follow-up paper. We will also apply the techniques described here to produce an all-Southern-sky RM catalogue from RACS observations. Finally, we make our catalogue, spectra, images, and processing pipeline publicly available
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