42 research outputs found

    Evaluation of Gateway and Low-Cost Traffic-Calming Treatments for Major Routes in Small Rural Communities

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    Many rural communities have developed around highways or major county roads; as a result, the main street through small rural communities is often part of a high-speed rural highway. Highways and county roads are characterized by high speeds outside the city limits; they then transition into a reduced speed section through the rural community. Consequently, drivers passing through the community often enter at high speeds and maintain those speeds as they travel through the community. Traffic calming in small rural communities along major roadways is common in Europe, but the U.S. does not have experience with applying traffic-calming measures outside of major urban areas. The purpose of the project was to evaluate traffic-calming treatments on the major road through small Iowa communities using either single-measure low-cost or gateway treatments. The project was partially funded by the Iowa Highway Research Board (IHRB). The focus of the IHRB portion was to evaluate single-measure, low-cost, traffic-calming measures that are appropriate to major roads through small rural communities. Seven different low-cost traffic treatments were implemented and evaluated in five rural Iowa communities. The research evaluated the use of two gateway treatments in Union and Roland; five single-measure treatments (speed table, on-pavement “SLOW” markings, a driver speed feedback sign, tubular markers, and on-pavement entrance treatments) were evaluated in Gilbert, Slater, and Dexter

    Toolbox to Assess Tradeoffs between Safety, Operations, and Air Quality for Intersection and Access Management Strategies

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    Significant transportation agency resources are allocated to meet maintenance, operations, safety, and air quality goals. Although there is a significant amount of overlap between these areas, decisions to meet agency goals in one area often do not consider goals in the others and, as a result, miss opportunities to leverage funds and make better informed decisions overall. There are a number of areas of overlap between capital improvements designed to improve operations, maintenance, safety, and air quality goals that provide a rich opportunity to leverage funds and use resources more cost-effectively while meeting agency goals in two or more of the areas. The objective of this research is to develop analytical tools that can efficiently evaluate common capital projects used to meet agency goals in one area (operations, safety, air quality, and maintenance) but that also have a significant impact on the others

    Understanding Oversize/Overweight Industry Freight Flow and Safety in Kansas Using the Kansas Truck Routing and Intelligent Permitting System (K-TRIPS) [Technical Summary]

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    The Kansas Department of Transportation (KDOT) developed an automated permitting system called the Kansas Truck Routing and Intelligent Permitting System (K-TRIPS) to issue permits for all OSOW trucks. Using four years of data from K-TRIPS (2014\u20122017), the research team developed a series of heat maps using ArcGIS to help visualize the routes OSOW trucks were using to travel through the state of Kansas. It was found that around 87 percent of the approximately 72,000 annual OSOW trips in Kansas were taken by five industries (general construction equipment, general freight, agriculture equipment/implements, wind energy, and oil and gas equipment), and that the majority of fluctuation in the consistency of routes travelled came from two industries (wind energy and oil and gas equipment)

    Task Features Change the Relation Between Math Anxiety and Number Line Estimation Performance With Rational Numbers: Two Large-Scale Online Studies

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    Math performance is negatively related to math anxiety (MA), though MA may impact certain math skills more than others.We investigated whether the relation between MA and math performance is affected by task features, such as number type (e.g., fractions, whole numbers, percentages), number format (symbolic vs. nonsymbolic), and ratio component size (small vs. large). Across two large-scale studies (combined n = 3,822), the MA-performance relation was strongest for large whole numbers and fractions, and stronger for symbolic than nonsymbolic fractions. The MA-performance relation was also stronger for smaller relative to larger components, and MA relating to specific number types may be a better predictor of performance than general MA for certain tasks. The relation between MA and estimation performance changes depending on task features, which suggests that MA may relate to certain math skills more than others, which may have implications for how people reason with numerical information and may inform future interventions

    Observational and Dynamical Characterization of Main-Belt Comet P/2010 R2 (La Sagra)

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    We present observations of comet-like main-belt object P/2010 R2 (La Sagra) obtained by Pan-STARRS 1 and the Faulkes Telescope-North on Haleakala in Hawaii, the University of Hawaii 2.2 m, Gemini-North, and Keck I telescopes on Mauna Kea, the Danish 1.54 m telescope at La Silla, and the Isaac Newton Telescope on La Palma. An antisolar dust tail is observed from August 2010 through February 2011, while a dust trail aligned with the object's orbit plane is also observed from December 2010 through August 2011. Assuming typical phase darkening behavior, P/La Sagra is seen to increase in brightness by >1 mag between August 2010 and December 2010, suggesting that dust production is ongoing over this period. These results strongly suggest that the observed activity is cometary in nature (i.e., driven by the sublimation of volatile material), and that P/La Sagra is therefore the most recent main-belt comet to be discovered. We find an approximate absolute magnitude for the nucleus of H_R=17.9+/-0.2 mag, corresponding to a nucleus radius of ~0.7 km, assuming an albedo of p=0.05. Using optical spectroscopy, we find no evidence of sublimation products (i.e., gas emission), finding an upper limit CN production rate of Q_CN<6x10^23 mol/s, from which we infer an H2O production rate of Q_H2O<10^26 mol/s. Numerical simulations indicate that P/La Sagra is dynamically stable for >100 Myr, suggesting that it is likely native to its current location and that its composition is likely representative of other objects in the same region of the main belt, though the relatively close proximity of the 13:6 mean-motion resonance with Jupiter and the (3,-2,-1) three-body mean-motion resonance with Jupiter and Saturn mean that dynamical instability on larger timescales cannot be ruled out.Comment: 23 pages, 13 figures, accepted for publication in A

    Tau-targeting antisense oligonucleotide MAPTRx in mild Alzheimer’s disease: a phase 1b, randomized, placebo-controlled trial

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    Tau plays a key role in Alzheimer’s disease (AD) pathophysiology, and accumulating evidence suggests that lowering tau may reduce this pathology. We sought to inhibit MAPT expression with a tau-targeting antisense oligonucleotide (MAPTRx) and reduce tau levels in patients with mild AD. A randomized, double-blind, placebo-controlled, multiple-ascending dose phase 1b trial evaluated the safety, pharmacokinetics and target engagement of MAPTRx. Four ascending dose cohorts were enrolled sequentially and randomized 3:1 to intrathecal bolus administrations of MAPTRx or placebo every 4 or 12 weeks during the 13-week treatment period, followed by a 23 week post-treatment period. The primary endpoint was safety. The secondary endpoint was MAPTRx pharmacokinetics in cerebrospinal fluid (CSF). The prespecified key exploratory outcome was CSF total-tau protein concentration. Forty-six patients enrolled in the trial, of whom 34 were randomized to MAPTRx and 12 to placebo. Adverse events were reported in 94% of MAPTRx-treated patients and 75% of placebo-treated patients; all were mild or moderate. No serious adverse events were reported in MAPTRx-treated patients. Dose-dependent reduction in the CSF total-tau concentration was observed with greater than 50% mean reduction from baseline at 24 weeks post-last dose in the 60 mg (four doses) and 115 mg (two doses) MAPTRx groups. Clinicaltrials.gov registration number: NCT03186989

    BMP-2 Dependent Increase of Soft Tissue Density in Arthrofibrotic TKA

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    Arthrofibrosis after total knee arthroplasty (TKA) is difficult to treat, as its aetiology remains unclear. In a previous study, we established a connection between the BMP-2 concentration in the synovial fluid and arthrofibrosis after TKA. The hypothesis of the present study was, therefore, that the limited range of motion in arthrofibrosis is caused by BMP-2 induced heterotopic ossifications, the quantity of which is dependent on the BMP-2 concentration in the synovial fluid

    Evaluation of Large Truck Crashes at Horizontal Curves on Two-Lane Rural Highways in Kansas

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    The objective of this study was to investigate the relationship between roadway and environment-related factors and truck crash severity at horizontal curves located on rural, two-lane state highways in Kansas. Single vehicle truck crashes and multi-vehicle crashes involving at least one truck were extracted from the Kansas Department of Transportation’s crash and roadway databases for the years 2006-2010, resulting in 452 crash records. Descriptive statistics and 95 percent confidence intervals were constructed for an odds ratio analysis comparing single-vehicle truck crashes to multi-vehicle crashes involving at least one truck for the variables that were included in both databases. Overall, the odds ratio analysis indicated that single vehicle truck crashes were less likely to occur on wet pavement with shoulder rumble strips present and during non-adverse weather conditions compared to multi-vehicle crashes involving at least one truck. Single-vehicle truck crashes were also more likely to result in an injury crash compared to multi-vehicle crashes involving at least one truck. The latter were more likely to result in a fatality or property damage only crash

    A Preliminary Appraisal of the Safety and Operational Effects on the Regional Transportation System Caused by New Rail- Truck Intermodal Facilities

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    Potential for impacts to a small Kansas city were evaluated in light of a planned rail to truck intermodal facility. The city of Edgerton, Kansas, was selected for an intermodal terminal in 2006 by a Class I railroad due to its regional proximity to the Kansas City market and market conditions favorable to such a facility. Through an analysis of various reports and literature along with original traffic, railroad, and environmental data, along with citizen feedback, the framework was laid to be able to compare the impacts of the facility to a snapshot in time prior to its opening
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