251 research outputs found

    KY-CTDS Kentucky Contract Time Determination System (KYSPR 99-195-lF)

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    This paper reports on the results of research that was funded by the Kentucky Transportation Cabinet (KyTC) to develop a new method for determining construction contract time for its highway construction contracts. The current and other DOT systems were analyzed to determine how a new system could provide better estimated duration. It was pre-determined that a PC computer based system was best suited. The development of the system input was developed from KyTC engineers with construction experience. The study advisory committee worked with Kentucky Transportation Center research engineers to develop the basis for the new contract time determination system, called KY-CTDS. The KY-CTDS program provides a conceptual estimating tool for predicting construction contract time for the Kentucky Department of Highways. It uses the pre-determined project classifications with only the major activities that control the project duration. Production rates and activity relationships were determined and are included in the program. Final adjustments in the project can be easily made by KyTC engineers. This system utilizes Microsoft Project® 98 and Microsoft Excel® Version 7.0 software operating on a personal computer. System outputs include a graphical bar chart schedule for estimating the contract time for bidding purposes. System output may also help in resolving construction disputes. The program is not suitable for detailed scheduling of construction operations

    The Paris to Lexington Road Reconstruction Project

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    This report summarizes the effort to provide the Kentucky Transportation Cabinet with an evaluation of the results obtained for the Paris to Lexington Road Reconstruction Project from 1997 to 2001. A unique pre-qualification process was used for the project to select a fixed pool of contractor to provide input to the design and to bid on the work. The research started in 1996 during the design process and continued following construction until September of 2001. Input was received from the Cabinet personnel working on the project, from the design firms, from the contractors, from the property owners involved, and from the citizen\u27s advisory committee overseeing the project. This was an environmentally sensitive project requiring special design and construction practices to meet the project objectives. An evaluation was done on 15 key project attributes and the project cost. Although more expensive than traditional highway projects the project was very successful. It is an example of how a highway department can successfully partner with the other stakeholders in a historic and environmentally sensitive project. Several observations and conclusions are included in the report

    Evaluation of Working Capacity for Disadvantaged Business Enterprises (DBE) For Highway Construction in Kentucky, FY 2004 Update

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    The Kentucky Transportation Center gathered the appropriate information, performed a series of computations and analyses, prepared the attached documentation, and makes the following recommendations to the Kentucky Transportation Cabinet for their DBE goal for Federal Fiscal year 2004 (October 1, 2003 - September 30, 2004). KTC recommends an overall DBE goal of 9.26%, of which 1.931% is anticipated to be satisfied by race/gender neutral prime contracts, and the resultant 7.33% should established as race/gender conscious subcontracts. The overall DBE goal figures stated here addresses an adjustment of 1.326% for the positive historical goal variance observed for the past eight years

    Development of a Critical Path Method Specification and a Training Program for use of CPM for KyTC

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    The Critical Path Method scheduling technique is outlined as it applies to KYTC projects. Special Provision 82 (94) and its requirements are outlined

    The Transcriptome of Human Endometrial Mesenchymal Stem Cells Under TGFβR Inhibition Reveals Improved Potential for Cell-Based Therapies

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    Mesenchymal stem/stromal cells (MSCs) are multipotent cells with favorable properties for cell therapies and regenerative medicine. Human endometrium harbors a small population of perivascular, clonogenic MSCs (eMSCs) identified by the SUSD2 marker. As for other MSCs, eMSCs require extensive in vitro expansion to generate clinically relevant numbers of cells, resulting in spontaneous differentiation, replicative senescence and cell death, decreasing therapeutic potency. We previously demonstrated that A83-01, a TGF-β receptor inhibitor, maintained eMSC clonogenicity, promoted proliferation, prevented apoptosis and maintained MSC function in vitro. Here we compare the transcriptome of passaged eMSCs from six women cultured with and without A83-01 for 7 days. We identified 1206 differentially expressed genes (DEG) using a false discovery rate cut-off at 0.01 and fold change >2. Significant enrichment of genes involved in anti-inflammatory responses, angiogenesis, cell migration and proliferation, and collagen fibril and extracellular matrix organization were revealed. TGF-β, Wnt and Akt signaling pathways were decreased. Anti-fibrotic and anti-apoptotic genes were induced, and fibroblast proliferation and myofibroblast related genes were downregulated. We found increased MSC potency genes (TWIST1, TWIST2, JAG1, LIFR, and SLIT2) validating the enhanced potency of A83-01-treated eMSCs, and importantly no pluripotency gene expression. We also identified eMSCs’ potential for secreting exosomes, possibly explaining their paracrine properties. Angiogenic and cytokine protein arrays confirmed the angiogenic, anti-fibrotic and immunomodulatory phenotype of A83-01-treated eMSCs, and increased angiogenic activity was functionally demonstrated in vitro. eMSCs culture expanded with A83-01 have enhanced clinically relevant properties, suggesting their potential for cell-therapies and regenerative medicine applications

    Direct observation of nuclear reorganization driven by ultrafast spin transitions

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    One of the most basic molecular photophysical processes is that of spin transitions and intersystem crossing between excited states surfaces. The change in spin states affects the spatial distribution of electron density through the spin orbit coupling interaction. The subsequent nuclear reorganization reports on the full extent of the spin induced change in electron distribution, which can be treated similarly to intramolecular charge transfer with effective reaction coordinates depicting the spin transition. Here, single-crystal [FeII(bpy)3] (PF6)2, a prototypical system for spin crossover (SCO) dynamics, is studied using ultrafast electron diffraction in the single-photon excitation regime. The photoinduced SCO dynamics are resolved, revealing two distinct processes with a (450 ± 20)-fs fast component and a (2.4 ± 0.4)-ps slow component. Using principal component analysis, we uncover the key structural modes, ultrafast Fe–N bond elongations coupled with ligand motions, that define the effective reaction coordinate to fully capture the relevant molecular reorganization

    The HARE chip for efficient time-resolved serial synchrotron crystallography

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    Serial synchrotron crystallography (SSX) is an emerging technique for static and time-resolved protein structure determination. Using specifically patterned silicon chips for sample delivery, the `hit-and-return' (HARE) protocol allows for efficient time-resolved data collection. The specific pattern of the crystal wells in the HARE chip provides direct access to many discrete time points. HARE chips allow for optical excitation as well as on-chip mixing for reaction initiation, making a large number of protein systems amenable to time-resolved studies. Loading of protein microcrystals onto the HARE chip is streamlined by a novel vacuum loading platform that allows fine-tuning of suction strength while maintaining a humid environment to prevent crystal dehydration. To enable the widespread use of time-resolved serial synchrotron crystallography (TR-SSX), detailed technical descriptions of a set of accessories that facilitate TR-SSX workflows are provided
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