3,478 research outputs found

    Safety and Mobility Analysis of Rolling Slowdown for Work Zones: Comparison with Full Closure

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    There are times when the traffic lanes through a work zone must be kept clear for activities such as placing overhead beams, erecting overhead signs, and installing power lines, and other temporary roadway work activities. As an alternative to a full road closure, a rolling slowdown can typically provide up to 30 minutes to complete such activities without bringing approaching traffic to a complete halt. Using data from recent rolling slowdowns and full closures carried on the Indiana interstate network and a simulation approach, this study compares rolling slowdowns to full closures from safety and mobility standpoints. The study suggests that while rolling slowdowns are more impactful in terms of travel times, they are a safer option than full closures as they often form a forward moving shockwave causing, lower hard braking rates, and consequently a lower probability of causing a crash

    Early warning device for detection of pollutants in water

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    Due to a growing need to protect water resources from contamination, there is a requirement for the development of more reliable and cost effective devices for water quality monitoring. The aim of the AQUAWARN project is to develop and deploy a fully autonomous water quality monitoring device that can measure nitrite, nitrate, phosphate and pH colorimetrically in fresh water and wastewater, and communicate the information to stakeholders in real time

    Early warning pollution detection device for application in water quality

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    It has been well recognised that water is a valuable resource and the quality of our water systems require sampling at a higher temporal and spatial frequency than is currently taking place. The AQUAWARN project aims to meet this challenge through the development of commercially competitive water quality monitoring devices. These will be capable of performing analytical measurements in situ - primarily aimed at freshwater and wastewater systems. The analytes of interest are mainly phosphate, nitrite, nitrate, and pH. The initial focus of this project is the assessment and optimisation of appropriate colorimetric chemistries for each sensing target. These chemistries have been developed and optimised using bench-top instrumentation. Integration within microfluidic chips followed to reduce the per sample costs. Microfluidic technology uses minute amounts of reagent per sample measurement, allowing for a dramatic increase in the number of potential assays per unit volume of reagent. Moreover, the integration of LEDs and photodiodes as light sources and detectors, coupled with syringe pumps, opens the way to new generations of low-cost, portable, and autonomous devices, capable of performing multiple in-situ measurements.  For example, an analysis requiring 50 uL of reagent implies 2,000 measurements are possible per 100 mL of reagent

    Three Dimensional Measurements of Asphaltene Deposition in a Transparent Micro-Channel

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    This study describes a novel experimental approach to directly measure the thicknesses of asphaltene deposits in micro-channels. The thickness of the asphaltene deposit is estimated using a visualization technique based on 3D digital microscopy. The working fluid is a mixture of n-heptane and dead oil. Induced by the addition of n-heptane, the asphaltenes present in crude oil phase separate at ambient temperature to form aggregates of asphaltene-rich phase. Part of the asphaltene aggregates deposit on the walls of the transparent micro-channel. A two-dimensional profile of the deposit across the channel at selected axial sections is measured. The influences of injection mixture volume on the growth of the thickness of deposited asphaltenes is investigated using two experimental conditions, (i) varying elapsed time at constant flow rate and (ii) increasing the flow rate at a constant elapsed time. In both cases the deposit thickness of asphaltene (δ) increases with the total injection volume (V). The experimental results obtained in this work provide new insights into the deposition process at the micro-scale level, which can be used to facilitate the development of more accurate numerical model for this applicatio

    Tamarix minoa (Tamaricaceae), a new species from the island of Crete (Greece) based on morphological and plastid molecular sequence data

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    Tamarix minoa is described from material collected on the S Aegean island of Crete (Kriti), Greece. A morphological comparison with the species considered to be closest, T. africana and T. hampeana, is provided. An original illustration showing the main morphological characters of the new species is also given, as are photographs of the new species in its habitat. The isolated phylogenetic position of T. minoa is shown to be strongly supported by plastid molecular sequence data (trnS-trnG, trnQ-rps16 and ndhF-rpl32), thus warranting its recognition at specific rank.National Geographic Society, research project “Human recreation versus plant diversity on maritime sands in Crete” (NGS grant no. 8573-08). The FPU programme (Mº de Educación, Spain), the I+D+I project CGL2008-05056 (Mº de Educación y Ciencia, Spanish Government), the project OAPN 354-2011 (Mº de Agricultura, Alimentación y Medio Ambiente, Spanish Government) and complementary supporting funds ACIE10-01, ACIE11-05 and ACIE13-08 (University of Alicante, Spain)

    Infection importation: a key challenge to malaria elimination on Bioko Island, Equatorial Guinea.

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    BACKGROUND: The impact of importation of falciparum malaria from mainland Equatorial Guinea on malaria infection in non-travellers and travellers on Bioko Island was examined. METHODS: Malaria indicator surveys were conducted in 2013 and 2014 to assess the association between malaria infection and travel to the mainland. Infection in non-travellers was compared in neighbourhoods of high travel and neighbourhoods of low travel. Boat passengers leaving from and arriving on the island were tested for infection. RESULTS: Children who had travelled to the mainland in the previous eight weeks were at greater risk of infection than those who had not travelled (56 vs 26% in 2013; 42 vs 18% in 2014). Children who had not travelled, living in localities with the highest proportion of travellers, were significantly more likely to be infected compared to those in localities with the smallest proportion of travellers (adjusted odds ratios 7.7 (95% CI 2.3-25) and 5.3 (95% CI 2.5-11) in 2013 and 2014, respectively). Infection in arriving boat passengers was substantially higher than in those departing (70 vs 38%, p = 0.017). DISCUSSION: Malaria importation by travellers poses a serious public health challenge affecting non-travellers as well as travellers

    Different involvement of medial prefrontal cortex and dorso-lateral striatum in automatic and controlled processing of a future conditioned stimulus

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    Recent studies support the idea that stimulus processing in latent inhibition can vary during the course of preexposure. Controlled attentional mechanisms are said to be important in the early stages of preexposure, while in later stages animals adopt automatic processing of the stimulus to be used for conditioning. Given this distinction, it is possible that both types of processing are governed by different neural systems, affecting differentially the retrieval of information about the stimulus. In the present study we tested if a lesion to the dorso-lateral striatum or to the medial prefrontal cortex has a selective effect on exposure to the future conditioned stimulus (CS). With this aim, animals received different amounts of exposure to the future CS. The results showed that a lesion to the medial prefrontal cortex enhanced latent inhibition in animals receiving limited preexposure to the CS, but had no effect in animals receiving extended preexposure to the CS. The lesion of the dorso-lateral striatum produced a decrease in latent inhibition, but only in animals with an extended exposure to the future conditioned stimulus. These results suggest that the dorsal striatum and medial prefrontal cortex play essential roles in controlled and automatic processes. Automatic attentional processes appear to be impaired by a lesion to the dorso-lateral striatum and facilitated by a lesion to the prefrontal cortex.Ministerio de Economía, Industria y Competitividad PSI2015-65500-

    The calcilytic agent NPS 2143 rectifies hypocalcemia in a mouse model with an activating calcium-sensing-receptor (CaSR) mutation:relevance to autosomal dominant hypocalcemia type 1 (ADH1)

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    Autosomal dominant hypocalcemia type 1 (ADH1) is caused by germline gain-of-function mutations of the calcium-sensing receptor (CaSR) and may lead to symptomatic hypocalcemia, inappropriately low serum parathyroid hormone (PTH) concentrations and hypercalciuria. Negative allosteric CaSR modulators, known as calcilytics, have been shown to normalise the gain-of-function associated with ADH-causing CaSR mutations in vitro and represent a potential targeted therapy for ADH1. However, the effectiveness of calcilytic drugs for the treatment of ADH1-associated hypocalcemia remains to be established. We have investigated NPS 2143, a calcilytic compound, for the treatment of ADH1 by in vitro and in vivo studies involving a mouse model, known as Nuf, which harbors a gain-of-function CaSR mutation, Leu723Gln. Wild-type (Leu723) and Nuf mutant (Gln723) CaSRs were expressed in HEK293 cells and the effect of NPS 2143 on their intracellular calcium responses determined by flow cytometry. NPS 2143 was also administered as a single intraperitoneal bolus to wild-type and Nuf mice and plasma concentrations of calcium and PTH, and urinary calcium excretion measured. In vitro administration of NPS 2143 decreased the intracellular calcium responses of HEK293 cells expressing the mutant Gln723 CaSR in a dose-dependent manner, thereby rectifying the gain-of-function associated with the Nuf mouse CaSR mutation. Intraperitoneal injection of NPS 2143 in Nuf mice led to significant increases in plasma calcium and PTH without elevating urinary calcium excretion. These studies of a mouse model with an activating CaSR mutation demonstrate NPS 2143 to normalize the gain-of-function causing ADH1, and improve the hypocalcemia associated with this disorder
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