Functionality screening to help design effective materials for radioiodine abatement

This paper is part of a growing body of research work looking at the synthesis of an optimal adsorbent for the capture and containment of aqueous radioiodine from nuclear fuel reprocessing waste. 32 metalated commercial ion exchange resins were subjected to a two-tier screening assessment for their capabilities in the uptake of iodide from aqueous solutions. The first stage determined that there was appreciable iodide capacity across the adsorbent range (12–220 mg·g−1). Candidates with loading capacities above 40 mg·g−1 were progressed to the second stage of testing, which was a fractional factorial experimental approach. The different adsorbents were treated as discrete variables and concentrations of iodide, co-contaminants and protons (pH) as continuous variables. This gave rise to a range of extreme conditions, which were representative of the industrial challenges of radioiodine abatement. Results were fitted to linear regression models, both for the whole dataset (R2 = 59%) and for individual materials (R2 = 18–82%). The overall model determined that iodide concentration, nitrate concentration, pH and interactions between these factors had significant influences on the uptake. From these results, the top six materials were selected for project progression, with others discounted due to either poor uptake or noticeable iodide salt precipitation behaviour. These candidates exhibited reasonable iodide uptake in most experimental conditions (average of >20 mg·g−1 hydrated mass), comparing favourably with literature values for metallated adsorbents. Ag-loaded Purolite S914 (thiourea functionality) was the overall best-performing material, although some salt precipitation was observed in basic conditions. Matrix effects not withstanding it is recommended that metalated thiourea, bispicolylamine, and aminomethylphosphonic acid functionalized silicas warrant further exploration

Shape abnormalities of the caudate nucleus correlate with poorer gait and balance : results from a subset of the ladis study

Objective Functional deficits seen in several neurodegenerative disorders have been linked with dysfunction in frontostriatal circuits and with associated shape alterations in striatal structures. The severity of visible white matter hyperintensities (WMHs) on magnetic resonance imaging has been found to correlate with poorer performance on measures of gait and balance. This study aimed to determine whether striatal volume and shape changes were correlated with gait dysfunction. Methods Magnetic resonance imaging scans and clinical gait/balance data (scores from the Short Physical Performance Battery [SPPB]) were sourced from 66 subjects in the previously published LADIS trial, performed in nondisabled individuals older than age 65 years with WMHs at study entry. Data were obtained at study entry and at 3-year follow-up. Caudate nuclei and putamina were manually traced using a previously published method and volumes calculated. The relationships between volume and physical performance on the SPPB were investigated with shape analysis using the spherical harmonic shape description toolkit. Results There was no correlation between the severity of WMHs and striatal volumes. Caudate nuclei volume correlated with performance on the SPPB at baseline but not at follow-up, with subsequent shape analysis showing left caudate changes occurred in areas corresponding to inputs of the dorsolateral prefrontal, premotor, and motor cortex. There was no correlation between putamen volumes and performance on the SPPB. Conclusion Disruption in frontostriatal circuits may play a role in mediating poorer physical performance in individuals with WMHs. Striatal volume and shape changes may be suitable biomarkers for functional changes in this population

Congestion pricing schemes controlled by the gMFD: A comprehensive design and appraisal to bridge the engineering and economic perspective

Charging drivers for the congestion they cause is a well-known concept among economists, traffic engineers and transport professionals. Many studies have been performed to explore and better address this issue during the history of transport economics and in recent years the first congestion pricing schemes have been finally implemented in some cities (Singapore, London, Stockholm). Nonetheless, several theoretical and practical problems still restrain this measure from being widely adopted. The lack of consistency with the traffic engineering perspective and limited degree of realism represent the main theoretical limitations of traditional congestion pricing models. The public resistance and fair distribution of gains and losses are the major practical barriers to the implementation of congestion pricing schemes. In this thesis, we discuss congestion pricing models controlled by the gMFD within agent-based simulation (MATSim). With this approach we seek efficient tolling schemes from an economic and traffic perspective. Furthermore, by means of investigations of the distributional effects of the proposed schemes we look for the strategy that maximizes the social welfare and with the highest potential acceptability. In the first phase of this study, through a review of theoretical studies and real experiences we identify the main reasons behind and factors influencing public resistance to the introduction of congestion pricing measures. Particularly, the question of equity is discussed in order to derive the necessary background for the evaluation of distributional effects. A thorough review of the major congestion pricing models proposed to date is made to construct our model. The survey goes from the traditional approaches like Marginal Cost Pricing and the bottleneck model to the most recent approaches based on macroscopic traffic models. During the review we discuss the main advantages and drawbacks of each approach. In the end, we describe the concept of Macroscopic Fundamental Diagram (MFD) and introduce important issues like the distribution of traffic and the phenomenon of hysteresis. The experiment is set up with MATSim to study the metropolitan area of Zurich. First, we test the consistency of simulation outputs with the traffic flow theory by playing with different parameters of the traffic model in order to obtain the most reliable result. Then, we derive and explore the main macroscopic traffic relations of the network defined by the cordon. This analysis shows the influence of distribution of traffic, expressed by the spatial spread of density, on the performance of the network. Furthermore, this property can be associated to the phenomenon of hysteresis loops. In order to account for this additional complexity, a generalized macroscopic fundamental diagram (gMFD) is experimentally derived to express the relationship between accumulation, production and spread of density. Finally, three tolling schemes differently controlled by the gMFD are designed: a uniform toll (Flat Toll) that allows the system working below the critical accumulation threshold; a time-varying toll (Step Toll) that charges drivers according to the total delay inside the cordon estimated through the gMFD; the Spread Toll that explicitly considers the question of spatial distribution of traffic inside the cordon. In particular, the Step Toll applies a charge in order to completely eliminate delay, whereas the Spread Toll penalizes users only for actual delays due to the overall increase of demand rather than clustering of congestion. By integrating different aspects like the traffic performance improvements, travel behavior responses and economic impacts we carry out a comprehensive evaluation of the schemes. In this broad appraisal framework the typical traffic enhancement measurements (heaviness of congestion, delays etc.) are combined with economic indicators such as the variation of agents’ utility. An analysis of travel behavior responses is carried out to identify the major trends associated with the tolling schemes and possible relationships with the traffic and economic impacts. Different socio-demographic groups are defined in order to evaluate the distributional impacts on inhabitants of different neighborhoods and areas, and on different trip purposes (work, home, education, shopping and leisure). Finally, considerations on the potential levels of public acceptance of the schemes are made on the basis of some indicators such as the share of winners, the average gain and loss, and the benefit-cost ratio. The proposed schemes have shown to perform differently from each other. While the Step Toll and the Flat Toll determine comparable traffic enhancements, the first one outperforms the second one in terms of economic impacts and distributional effects. The smoother adaptation of demand determined by the Step Toll is probably its strong point. The Spread Toll, which was conceived as the fairest scheme, does not produce any considerable traffic improvement and it is even detrimental from the economic perspective. As to the question of public acceptance, although the slightly lower share of winners, the Step Toll determines higher gains than the other two schemes. Hence, from a social welfare perspective (combination of efficiency and distributional impacts), the Step Toll is the best performing scheme, followed by the Flat Toll and Spread Toll. Besides these results, the investigations of macroscopic traffic properties of networks have shed light on important aspects of the traffic flow theory. First, the distribution of congestion expressed as spatial spread of density has considerable influence on the network performance. This property could be modeled in heterogeneous networks by introducing the spread as additional variable in the gMFD. Second, hysteresis loops in the MFD plane occur in presence of congestion and their pattern can be identified with the spread. Furthermore, the decrease of performance seems to be related to the frequency of loading-unloading cycles.Transport and PlanningTransport & PlanningCivil Engineering and Geoscience

Congestion pricing based on dynamic features of the Macroscopic Fundamental Diagram

Studies into optimal congestion pricing are typically based on analytical representations of travel choices and network traffic flows. In this paper we show how congestion pricing schemes (or more precisely, cordon tolls) can be derived from the concept of the Macroscopic Fundamental Diagram (MFD). This approach is consistent with the transport economic notion of marginal cost pricing, while it also enables to realistically account for the dynamics and heterogeneity in the (aggregated) network traffic flow conditions. To this end, we first analyze the hysterical dynamic relations between the macroscopic fundamental traffic variables of network speed, network production, network accumulation, and spatial variance in the network accumulation. Subsequently, we show how through these relations captured by the generalized MFD one can compute the marginal costs of a surplus of traffic inside the cordon area, which is then used as a basis to design a flat toll and step toll pricing scheme. Furthermore, a third tolling scheme is designed to explicitly account for the temporal hysteresis loops in the MFD and the influence of the spatial variance in network accumulation. The pricing framework is implemented in the agent-based simulation model MATSim and applied to a case study of the city of Zurich. The alternative tolling schemes are evaluated against a number of traffic performance indicators to show how these deal with the hysteresis and spatial variance in the network accumulation

Decarbonising the lime industry : state-of-the-art

The thermal treatment of limestone (mainly CaCO3) to produce lime (CaO) is a major contributor to CO2 emissions and the literature on decarbonising the lime industry is scarce. Subsequent hydration of lime would lead to the synthesis of slaked/hydrated lime Ca(OH)2; the production of a tonne of Ca(OH)2 emits ∼1.2 tonnes of CO2 arising mainly from the process chemistry and fossil fuel combustion. Carbon Capture & Storage (CCS) technologies are currently believed to have the highest potential to mitigate these CO2 emissions, assuming that the thermal calcination of CaCO3 is unavoidable. Despite intensive research efforts and development, CCS technologies cannot be industrially applied yet due to their limited efficiency and the associated capital and operational costs. In this review, the current state of the lime industry and its processing configurations is visualised. This is followed by a detailed description of the current status of the relevant CCS technologies (including their CO2 avoidance costs) and eco-efficient alternative fuels. This work then gives voice to two novel and potentially more sustainable decarbonisation routes that do not involve the thermal calcination of CaCO3, one of which involves simultaneous mineralisation leading to permanent storage of CO2. These technologies are particularly interesting especially if high temperature lime kilns, as we know them, are phased out to meet climate goals. It is revealed that the energy shift to green electricity might lead to a no-carbon lime industry and subsequent carbon neutrality (or negativity) of other hard-to-abate sectors

Introducing competition in urban consolidation center freight allocation modeling

Urban consolidation center (UCC) represents in many cities the most chosen solution by the local governments to reduce the negative impacts of city freight distribution. In order to achieve successful results, it is important to consider also the perspective of carriers with respect to the choice of facility location and the evaluation of costs. Therefore, in this paper we propose a simple approach to investigate the problem of flow distribution and choice of UCCs locations in situations of competition or cooperation among freight operators. In the first part of the paper, after presenting a brief explanation of the concept UCC, an overview of UCCs critical success factors is provided. This paper considers the modeling of competitive behavior among freight transport carriers into the optimization of urban freight distribution centers considering their incoming and outgoing flows. Three different types of scenarios are developed in order to represent different market situations of monopoly and duopoly competition in Cournot and von Stackelberg equilibriums. The outcomes of the model in terms of optimal configuration of UCCs, optimal distribution of freight flows, overall costs of the system and costs of carriers seem to be influenced by phenomena of competition, particularly in situations where a new competitor attempts to enter the market.Transport and PlanningCivil Engineering and Geoscience

Heart-fatty acid-binding and tau proteins relate to brain injury severity and long-term outcome in subarachnoid haemorrhage patients

BackgroundVasospasm and other secondary neurological insults may follow subarachnoid haemorrhage (SAH). Biomarkers have the potential to stratify patient risk and perhaps serve as an early warning sign of delayed ischaemic injury.MethodsSerial cerebrospinal fluid (CSF) samples were collected from 38 consecutive patients with aneurysmal SAH admitted to the neurosurgical intensive care unit. We measured heart-fatty acid-binding protein (H-FABP) and tau protein (\u3c4) levels in the CSF to evaluate their association with brain damage, and their potential as predictors of the long-term outcome. H-FABP and \u3c4 were analysed in relation to acute clinical status, assessed by the World Federation of Neurological Surgeons (WFNS) scale, radiological findings, clinical vasospasm, and 6-month outcome.ResultsH-FABP and \u3c4 increased after SAH. H-FABP and \u3c4 were higher in patients in poor clinical status on admission (WFNS 4-5) compared with milder patients (WFNS 1-3). Elevated H-FABP and \u3c4 levels were also observed in patients with early cerebral ischaemia, defined as a CT scan hypodense lesion visible within the first 3 days after SAH. After the acute phase, H-FABP, and \u3c4 showed a delayed increase with the occurrence of clinical vasospasm. Finally, patients with the unfavourable outcome (death, vegetative state, or severe disability) had higher peak levels of both proteins compared with patients with good recovery or moderate disability.ConclusionsH-FABP and \u3c4 show promise as biomarkers of brain injury after SAH. They may help to identify the occurrence of vasospasm and predict the long-term outcome. \ua9 The Author [2013]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved

Heart-fatty acid-binding and tau proteins relate to brain injury severity and long-term outcome in subarachnoid haemorrhage patients.

Background: Vasospasm and other secondary neurological insults may follow subarachnoid haemorrhage (SAH). Biomarkers have the potential to stratify patient risk and perhaps serve as an early warning sign of delayed ischaemic injury. Methods: Serial cerebrospinal fluid (CSF) samples were collected from 38 consecutive patients with aneurysmal SAH admitted to the neurosurgical intensive care unit. We measured heart-fatty acid-binding protein (H-FABP) and tau protein (\u3c4) levels in the CSF to evaluate their association with brain damage, and their potential as predictors of the long-term outcome. H-FABP and \u3c4 were analysed in relation to acute clinical status, assessed by the World Federation of Neurological Surgeons (WFNS) scale, radiological findings, clinical vasospasm, and 6-month outcome. Results: H-FABP and \u3c4 increased after SAH. H-FABP and \u3c4 were higher in patients in poor clinical status on admission (WFNS 4\u20135) compared with milder patients (WFNS 1\u20133). Elevated H-FABP and \u3c4 levels were also observed in patients with early cerebral ischaemia, defined as a CT scan hypodense lesion visible within the first 3 days after SAH. After the acute phase, H-FABP, and \u3c4 showed a delayed increase with the occurrence of clinical vasospasm. Finally, patients with the unfavourable outcome (death, vegetative state, or severe disability) had higher peak levels of both proteins compared with patients with good recovery or moderate disability. Conclusions: H-FABP and \u3c4 show promise as biomarkers of brain injury after SAH. They may help to identify the occurrence of vasospasm and predict the long-term outcome

Psycopatologycal status and coping strategies in psoriatic patient: objectives and methodology of the psoriasis survey for the control of anxiety and depression (PSYCHAE) study.

Psoriasis: SurveY for the Control of Anxiety and dEpression (PSYCHAE) is a multicentric, observational, prospective study for evaluation of the psychological impact and strategies for coping with psoriasis in Italian patients. A cohort of 1 580 patients was enrolled in 39 University Dermatological Departments in Italy. A total of 3 follow-up visits were programmed after enrollment. Psychological status was evaluated using specific psychometric scales (general health questionnaire [GHQ- 12], brief symptoms inventory [BSI], and Brief-Cope). GHQ- 12 was chosen due to its easy use and rapid clinical assessment of general psychological status. The BSI scale provides a structured and more in-depth analysis of psychological symptoms. Brief-Cope permits the analysis of cognitive stress regarding psoriasis. On the basis of the methodology chosen and the large number of patients enrolled, it is expected that the study will provide a realistic assessment of the psychopathologicalstatus of patients with psoriasis in Italy. The rationale behind the choice of the methodology utilized for obtaining objective results is discussed