725 research outputs found

    Constitutive equations in two-dimensional flow Final report, Sep. 1964 - Aug. 1969

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    Stress-strain equations for viscoelastic materials with emphasis on two dimensional flow

    Congestion-clearing payments to passengers

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    This paper reports on a project that considers whether the goals of (de)congestion pricing could be achieved in whole or in part by incentivizing mode-shift rather than using charging to force it: buying rather than selling decongestion. The project developed a method for estimating the net present value of the costs and benefits of a permanent ITS-enabled program of paying people to travel as passengers rather than as drivers-to reduce existing congestion in a target corridor to a target maximum level of delay-taking into account the mix of the traffic and the potential impact of latent demand and induced trips. This is relevant for making better use of existing infrastructure (a build nothing alternative to expansion, but not a do nothing one), for decarbonizing transport, and in the run up to automated vehicles where the possibility exists that new infrastructure investments in the 1-20-year timeframe will become stranded assets under some future scenarios. The project incorporated: a thorough review of the literature; focus groups; and a survey in a case study corridor in California to test the theory, develop the method, and determine the likely costs and benefits. The main insights include 1) the significance of an \u27intra-peak demand shift\u27 that would occur if congestion was removed; 2) the need for four major components in a congestion-clearing payments program: a) incentives to switch from driving to being a passenger, b) incentives to travel at less preferred times, c) park and ride/pool facilities near the bottleneck to ease the passenger switch, and d) some limitation on single-occupant vehicle travel in the peak-of-the-peak in order to reserve space for vehicles carrying passengers; and 3) the possible need for different land-use regulations in a successful payments to passengers environment where the amount of traffic might no longer be an obvious constraint for expanding the local economy. The case study benefit cost analysis delivers a benefit cost ratio of 4.5 to 1

    Thyroid-specific transcription factors control Hex promoter activity

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    The homeobox-containing gene Hex is expressed in several cell types, including thyroid follicular cells, in which it regulates the transcription of tissue-specific genes. In this study the regulation of Hex promoter activity was investigated. Using co-transfection experiments, we demonstrated that the transcriptional activity of the Hex gene promoter in rat thyroid FRTL-5 cells is ∼10-fold greater than that observed in HeLa and NIH 3T3 cell lines (which do not normally express the Hex gene). To identify the molecular mechanisms underlying these differences, we evaluated the effect of the thyroid-specific transcription factor TTF-1 on the Hex promoter activity. TTF-1 produced 3-4-fold increases in the Hex promoter activity. Gel-retardation assays and mutagenesis experiments revealed the presence of functionally relevant TTF-1 binding sites in the Hex promoter region. These in vitro data may also have functional relevance in vivo, since a positive correlation between TTF-1 and Hex mRNAs was demonstrated in human thyroid tissues by means of RT-PCR analysis. The TTF-1 effect, however, is not sufficient to explain the difference in Hex promoter activity between FRTL-5 and cells that do not express the Hex gene. For this reason, we tested whether Hex protein is able to activate the Hex promoter. Indeed, co-transfection experiments indicate that Hex protein is able to increase the activity of its own promoter in HeLa cells ∼4-fold. TTF-1 and Hex effects are additive: when transfected together in HeLa cells, the Hex promoter activity is increased 6-7-fold. Thus, the contemporary presence of both TTF-1 and Hex could be sufficient to explain the higher transcriptional activity of the Hex promoter in thyroid cells with respect to cell lines that do not express the Hex gene. These findings demonstrate the existence of direct cross-regulation between thyroid-specific transcription factors

    Congestion-Clearing Payments to Passengers

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    Peak period motor vehicle traffic volume congests roads all over the world. This project hypothesizes implementing congestion- clearing payments to passengers as a permanent congestion-management solution. Ongoing congestion-free travel would be achieved by removing existing congestion, and absorbing (re)generated demand, at costs that would be expected to increase as the total number of travelers increases over time. The project develops a comprehensive, step-by-step methodology to calculate the benefits and costs of paying for drivers to become passengers at a congestion-clearing level and to maintain this level over time. The method is derived from the literature, analysis by the project team, and development of a case study. The case study, based on a long-standing bottleneck location in California, enabled the project team to think through the real challenges of developing and evaluating such a solution. The project finds that the conceptual underpinning of the solution is sound. Based on a survey, the case study finds that there is a level of payment that could clear congestion and maintain free-flow for twenty years, with benefits that outweigh costs on a net present value basis by about four to one—though calibration is required. After the initial reward clears the queue at the bottleneck, a significant intra-peak demand shift would occur as existing and new travelers depart home at times that are more to their liking, potentially causing the queue to re-form. A second incentive manages time of travel, rewarding people for traveling as passengers earlier (or later) than the preferred high demand peak-of-the-peak. In the case study, the high proportion of people who say they will only drive alone would eventually result in some periods of single-occupant-vehicle-only traffic during peak, which is an unintended and undesirable consequence. For the case study route, a limit on single-occupant-vehicle travel during the peak- of-the-peak would ensure that high-occupancy-vehicle travel is given preference and would reduce the overall cost of the solution. For the case study, the cost of the congestion-clearing payments-to-passengers solution on a net present value basis is within the estimated range of costs of the alternative of expanding the facility, and the benefits are expected to be greater than for facility expansion. Congestion-clearing payments to passengers can be implemented much sooner and will have greater positive long-term economic impacts. Facility expansion would provide lower and shorter-term benefits and would be expected to return to congested conditions within a year. The project team proposes a pilot project on the case study route to test and calibrate the solution, as well as recommending development of further case study routes to find out how different routes vary and determine the causes of any variations

    Method for forming a pallet with deep drawn legs

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    A method for molding articles such as pallets from flake-like wood particles mixed with binder, the pallets housing a deck and integral molding legs. A loosely fitted mat of wood flakes is formed by depositing a first plurality of layers of wood flakes onto a supporting surface with a flake aligners provided for causing alignment of those flakes which will form legs of the pallet. A second plurality of layers are formed with a flake aligner provided for causing alignment of flakes which will form the legs of the pallet and in a direction transverse to the direction of alignment of the flakes of the first layers.https://digitalcommons.mtu.edu/patents/1097/thumbnail.jp

    Pallet and apparatus for forming a pallet with deep drawn legs

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    A method and apparatus for molding articles such as pallets from flake-like wood particles mixed with binder, the pallets housing a deck and integral molding legs. A loosly fitted mat of wood flakes is formed by depositing a first plurality of layers of wood flakes onto a supporting surface with a flake aligners provided for causing alignment of those flakes which will form legs of the pallet. A second plurality of layers are formed with a flake aligner provided for causing alignment of flakes which will form the legs of the pallet and in a direction transverse to the direction of alignment of the flakes of the first layers.https://digitalcommons.mtu.edu/patents/1081/thumbnail.jp

    The impact of a ward‐based pharmacy technician service in an Irish hospital

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    Introduction: Pharmacy technicians have been employed in hospital settings for many years, but only recently have their role been reviewed for potential expansion. Hospitals across Australia, the United Kingdom, and many other countries have implemented a ward‐based pharmacy technician service (1, 2), but this is yet to become common practice in Ireland. At present, there is only one published study on the development of the clinical role of pharmacy technicians in Ireland (3). Aim: The aim of this study was to determine if the expanded role of the ward‐based pharmacy technician role could have a positive impact on medicine management systems within a hospital ward. Methods: This study was carried out over 8 weeks in an Irish hospital. Sixteen wards were studied; four “intervention wards” which have the ward‐based technician service in situ, and 12 “control ward” which currently do not. Medicine management systems were assessed within these wards with respect to (1) the presence of excess non‐ward stock on drug trolleys, (2) the presence of expired medication on drug trolleys, and (3) the time taken by nurses to complete drug rounds. Results: The total cost value of the excess non‐stock items found on the intervention wards was €97.51 (the average cost per ward was €24.38). The total cost value of the excess non‐stock items found on the control wards was €13,767.76 (the average cost per ward was €1,147.31). Eight expired medications were found on the control wards; none were present on intervention wards. The ward‐based technician service reduced the average nursing time to complete drug rounds on a per‐patient basis by 28%. Conclusion: This study has demonstrated that the expanded role of the ward‐based pharmacy technician has had a positive impact in several ways; a reduction in the cost of non‐stock items present on the ward along with a reduction in expired stock present. Time taken to complete drug rounds was less on the intervention wards compared to control wards, thus, freeing up time for nurses to engage in other patient activities. Further studies should consider the full economic costing of the ward‐based pharmacy technician service

    The impact of a ward-based pharmacy technician service

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    Background: Pharmacy technicians have been employed in hospital settings for many years, but only recently has the potential for service expansion been explored. There is a paucity of research on the impact of a ward-based pharmacy technician service (WBPTS) in this country. Purpose: To determine the impact of a WBPTS on medicine management systems, patient safety and healthcare costs. Methods: Sixteen wards were studied over 8 weeks; four ‘intervention’ wards (already assigned a WBPTS prior to the study) and 12 ‘control’ wards (whereby technicians provide a stock ‘top-up’ service). The ‘intervention’ wards comprised mainly of medical patients; a WBPT had been assigned to each of these wards as they were considered high activity wards. The control wards comprised both medical and surgical patients. The medication management systems were inspected by the research team for the presence of excess non-stock medicines and expired medication. Nurses were observed by the research team to calculate time taken to complete drug rounds. Patient drug charts were analysed to calculate the duration to pharmacist review of high-risk medications. Nursing staff were surveyed on their opinions of the service. Results: The total value of excess non-stock on intervention wards was €97.51 (mean cost per ward: €24.38) compared with €13,767.76 on the control wards (mean cost per ward: €1,147.31). Eight expired medications were found on control wards; none were present on intervention wards. The mean time to complete drug rounds on a per-patient basis was 28% lower on intervention wards. The median time taken for pharmacist review of high-risk medications was shorter on intervention wards (0.67 days vs 4.2 days). 100% of respondents agreed that the WBPTS should continue. Conclusion: More widespread investment in the WBPTS has the potential to reduce healthcare expenditure due to excess medicines, increase nursing time spent on direct care of patients, and reduce the potential for patient harm from high-risk medicines. The current study did not consider the costs associated with providing this service (e.g. personnel costs, additional time spent by the technician/ time saved by nurses etc.) and so further studies should consider the full economic costing of the service

    Dialectics and difference: against Harvey's dialectical post-Marxism

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    David Harvey`s recent book, Justice, nature and the geography of difference (JNGD), engages with a central philosophical debate that continues to dominate human geography: the tension between the radical Marxist project of recent decades and the apparently disempowering relativism and `play of difference' of postmodern thought. In this book, Harvey continues to argue for a revised `post-Marxist' approach in human geography which remains based on Hegelian-Marxian principles of dialectical thought. This article develops a critique of that stance, drawing on the work of Jacques Derrida, Gilles Deleuze and Felix Guattari. I argue that dialectical thinking, as well as Harvey's version of `post-Marxism', has been undermined by the wide-ranging `post-' critique. I suggest that Harvey has failed to appreciate the full force of this critique and the implications it has for `post-Marxist' ontology and epistemology. I argue that `post-Marxism', along with much contemporary human geography, is constrained by an inflexible ontology which excessively prioritizes space in the theory produced, and which implements inflexible concepts. Instead, using the insights of several `post-' writers, I contend there is a need to develop an ontology of `context' leading to the production of `contextual theories'. Such theories utilize flexible concepts in a multilayered understanding of ontology and epistemology. I compare how an approach which produces a `contextual theory' might lead to more politically empowering theory than `post-Marxism' with reference to one of Harvey's case studies in JNGD
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