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This systematic review investigated the added value of intraoperative magnetic resonance imaging (iMRI)-guidance in epilepsy surgery, compared to conventional non-iMRI surgery, with respect to the rate of gross total resection (GTR), postoperative seizure freedom, neurological deficits, non-neurological complications and reoperations. A comprehensive literature search was conducted using Medline, Embase, PubMed, and Cochrane Reviews databases. Randomized control trials, case control or cohort studies, and surgical case series published from January 1993 to February 2021 that reported on iMRI-guided epilepsy surgery outcomes for either adults or children were eligible for inclusion. Studies comparing iMRI-guided epilepsy surgery to non-iMRI surgery controls were selected for meta-analysis using random-effects models. Forty-two studies matched the selection criteria and were used for qualitative synthesis and ten of these were suitable for meta-analysis. Overall, studies included various 0.2-3.0 Tesla iMRI systems, contained small numbers with heterogenous clinical characteristics, utilized subjective GTR reporting, and had variable follow-up durations. Meta-analysis demonstrated that the use of iMRI-guidance led to statistically significant higher rates of GTR (RR = 1.31 [95% CI = 1.10-1.57]) and seizure freedom (RR = 1.44 [95% CI = 1.12-1.84]), but this was undermined by moderate to significant statistical heterogeneity between studies (I2 = 55% and I2 = 71% respectively). Currently, there is only level III-2 evidence supporting the use of iMRI-guidance over conventional non-iMRI epilepsy surgery, with respect to the studied outcomes.

Four groups of toothed whales have independently evolved to produce narrowband high-frequency (NBHF) echolocation signals (i.e. clicks) with a strikingly similar waveform and centroid frequency around 125 kHz. These signals are thought to help NBHF species avoid predation by echolocating and communicating at frequencies inaudible to predators, a form of acoustic crypsis. Heaviside's dolphins produce NBHF echolocation clicks in trains and often in rapid succession in the form of buzzes. In addition, a second click type with a lower frequency and broader bandwidth was recently described, typically emitted in rapid succession in the form of burst-pulses. We investigated the relationship between buzz and burst-pulse signals and both surface behaviour (foraging, ‘interacting with the kayak’ and socializing) and group size, using a multivariable regression on the signal occurrence and signal count data. Signal occurrence and counts were not related to group size in the regression analysis. Burst-pulses were strongly linked to socializing behaviour, occurring more often and more frequently during socializing and much less during foraging. Buzz vocalizations were not strongly linked to a specific behaviour although there was some evidence of an increase in production during foraging and socializing. In addition, individual level production rates of buzzes during foraging and socializing, and burst-pulses during socializing decreased with increasing group size. Temporally patterned burst-pulse signals were also identified, often occurring within a series of burst-pulses and were directly linked to specific events such as aerial leaping, backflipping, tail slapping and potential mating. Our findings suggest Heaviside's dolphins have a more complex communication system based on pulsed vocalizations than previously understood, perhaps driven by the need to facilitate the social interactions of this species.

Carbon capture and storage (CCS) activities need to be ramped up to address the climate crisis. Abatement cost curves can help to identify low-cost starting points and formulate roadmaps for the implementation of CCS at industrial sites. In this work, we introduce the concept of energy supply cost curves to enhance the usefulness and accuracy of abatement cost curves. We use a multi-period mixed-integer linear programming (MILP) approach to find an optimal mix of heat sources considering the existing site energy system. For a Swedish refinery, we found that residual heat and existing boiler capacities can provide the heat necessary for CCS that avoids >75% of the site’s CO2 emissions. Disregarding the existing site energy system and relying on new heat supply capacities instead, would lead to capture costs that are 40–57% higher per tonne of CO2-avoided (excl. CO2 liquefaction, transport, and final storage). Furthermore, we estimated that temporal variations of heat sources (intermittent residual heat) increases the heat supply cost and emissions by 7–26% and 9–66%, respectively. The proposed method for optimization of the energy supply mix considering temporal variations of heat sources enables detailed estimates of energy supply costs for CO2 capture rates ranging from partial to full capture, and thus, improve abatement cost curves. The role of energy supply in abatement cost curves for CO2 capture from process industry – A case study of a Swedish refinery

Many studies indicate that carbon capture and storage operations need to be ramped up in the coming decades to limit global warming to well-below 2°C. Partial CO2 capture from carbon-intensive industrial processes is a promising starting point for initial CO2 transport and storage infrastructure projects, such as the Norwegian full-chain CCS project “Northern Lights”, since specific capture cost (€/t CO2) for single-stack capture can be kept low compared to full capture from all, often less suitable stacks. This work highlights the importance of utilizing existing site energy systems to avoid significant increase in marginal abatement cost when moving from partial to full capture. A systematic and comprehensive techno-economic approach is applied that identifies a mix of heat supply sources with minimum cost based on a detailed analysis of available heat and capacity within the existing site energy system. Time-dependent variations are considered via multi-period, linear optimization. For single-stack capture from the hydrogen production unit (~0.5 Mt CO2 p.a.) of a Swedish refinery in the context of the current energy system, we find avoidance cost for the capture plant (liquefaction, ship transport, and storage excluded)of 42 €/t CO2-avoided that is predominantly driven by steam raised from available process heat in existing coolers (~6 €/t steam). For full capture from all major stacks (~1.4 Mt CO2 p.a.), the avoidance cost becomes twice as high (86 €/t CO2-avoided) due to heat supply from available heat and existing boiler capacity (combustion of natural gas) at costs of ~20€/t steam. The analysis shows that very few investments in new steam capacity are required, and thus, that the utilization of existing site energy systems is important for lowering capture cost significantly, and thus the whole-chain cost for early CCS projects.

This paper presents an overview of the Preem CCS project, a co-funded Swedish-Norwegian R&D initiative. The project aims to demonstrate CO2 capture at Preem's refinery in Lysekil, Sweden and investigating the techno-economic and regulatory aspects of capturing CO2 at the refinery in Sweden and transporting the CO2 cross borders to Norway for final storage with the Northern Lights infrastructure. The Preem CCS project started in 2019 and is due to finish by the end of 2021.

The whale louse Cyamus boopis is a host-specific amphipod that parasitizes humpback whales (Megaptera novaeangliae) across the world. Humpback whales from the Southern Hemisphere are currently separated into seven breeding stocks, each with its own migration route to/from Antarctic waters. The aim of this study was to determine the population structure of C. boopis from the Southern Hemisphere using cytochrome oxydase I sequences, and compare it to that of its host species found in previous studies. High haplotype and nucleotide diversities in C. boopis were observed, and the populations from western south Atlantic (WSA: Brazil + Argentina − Breeding stock A) and western south Pacific (WSP: Australia - Breeding stock E) did not show any significant difference but were differentiated from populations of eastern south Atlantic (ESA: Namibia - Breeding stock B) and the north Pacific. The genetic homogeneity between WSA and WSP populations, might reveal a higher genetic transfer within the Southern Hemisphere, since the feeding grounds of whales which are distributed throughout the circumpolar Southern Ocean could allow inter-mixing of individuals from different breeding populations during the feeding season. The present data reinforces that population dynamics of humpback whales seem more complex than stable migration routes, which could have implications for both management of the species and cultural transmissions of behaviours. Fil: Iwasa Arai, Tammy. Universidade Federal do Rio de Janeiro; Brasil Fil: Serejo, Cristiana S.. Universidade Federal do Rio de Janeiro; Brasil Fil: Siciliano, Salvatore. Fundación Oswaldo Cruz; Brasil Fil: Ott, Paulo H.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Freire, Andrea S.. Universidade Federal de Santa Catarina; Brasil Fil: Elwen, Simon. Universiteit Van Pretoria; Sudáfrica Fil: Crespo, Enrique Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Colosio, Adriana C.. Instituto Baleia Jubarte; Brasil Fil: Carvalho, Vitor L.. Associação de Pesquisa E Preservação de Ecossistemas Aquáticos; Brasil Fil: Rodríguez Rey, Ghennie T.. Universidad de Caldas; Colombia. Universidade Federal do Rio de Janeiro; Brasil

Industry's increasing demand for liquefied natural gas could be met in the future by liquefied methane produced from biomass feedstock (LBG - liquefied biogas). This study presents results from an investigation of value chains for integrated production of LBG at a generic sawmill site, based on gasification of sawmill waste streams and forest residues. The objective was to investigate the cost for, as well as the carbon footprint reduction associated with, production and use of LBG as a fuel. Five different LBG plant sizes were investigated in combination with three different sawmill sizes. The resulting cases differ regarding biomass feedstock composition, biomass transportation distances, LBG plant sizes, how efficiently the excess heat from the LBG plant is used, and LBG distribution distances. Pinch technology was used to quantify the heat integration opportunities and to design the process steam network. The results show that efficient use of energy within the integrated process has the largest impact on the performance of the value chain in terms of carbon footprint. The fuel production cost are mainly determined by the investment cost of the plant, as well as feedstock transportation costs, which mainly affects larger plants. Production costs are shown to range from 68 to 156 EUR/MW hfuel and the carbon footprint ranges from 175 to 250 kg GHG-eq/MW hnet biomass assuming that the product is used to substitute fossil LNG fuel. The results indicate that process integration of an indirect biomass gasifier for LBG production is an effective way for a sawmill to utilize its by-products. Integration of this type of biorefinery can be done in such a way that the plant can still cover its heating needs whilst expanding its product portfolio in a competitive way, both from a carbon footprint and cost perspective. The results also indicate that the gains associated with efficient heat integration are important to achieve an efficient value chain.

Our previous studies suggest the tuber center is the seizure focus in tuberous sclerosis complex (TSC). We report findings from 5 epilepsy surgeries in 4 children with TSC and focal motor seizures from single tubers in primary sensorimotor cortex in which resection was limited to the cortex in the tuber center. Intraoperative electrocorticography showed epileptiform activity in the tuber center, with or without propagation to the tuber rim and surrounding perituberal cortex. Histopathology showed an abundance of dysmorphic neurons in the tuber center compared to the rim in four paired specimens, dysmorphic neurons being the reported epileptogenic cell line in TSC. Associated focal motor seizures were eliminated in all children (mean follow up 6.3 years) without postoperative deficits. Tuber center resections are a potential alternative to complete tuberectomy in patients with epileptogenic tubers in eloquent cortex and potentially also in children with a high tuber load and multifocal seizures.

Hypothalamic hamartoma (HH) with gelastic epilepsy is a well-recognized drug-resistant epilepsy syndrome of early life.(1) Surgical resection allows limited access to the small deep-seated lesions that cause the disease. Here, we report the results of a search for somatic mutations in paired hamartoma- and leukocyte-derived DNA samples from 38 individuals which we conducted by using whole-exome sequencing (WES), chromosomal microarray (CMA), and targeted resequencing (TRS) of candidate genes. Somatic mutations were identified in genes involving regulation of the sonic hedgehog (Shh) pathway in 14/38 individuals (37%). Three individuals had somatic mutations in PRKACA, which encodes a cAMP-dependent protein kinase that acts as a repressor protein in the Shh pathway, and four subjects had somatic mutations in GLI3, an Shh pathway gene associated with HH. In seven other individuals, we identified two recurrent and three single brain-tissue-specific, large copy-number or loss-of-heterozygosity (LOH) variants involving multiple Shh genes, as well as other genes without an obvious biological link to the Shh pathway. The Shh pathway genes in these large somatic lesions include the ligand itself (SHH and IHH), the receptor SMO, and several other Shh downstream pathway members, including CREBBP and GLI2. Taken together, our data implicate perturbation of the Shh pathway in at least 37% of individuals with the HH epilepsy syndrome, consistent with the concept of a developmental pathway brain disease.

T.G. was funded during the initial stages of this work by a NERC PhD studentship, a University of St Andrews Russell Trust Award and later the University of Pretoria Vice Chancellor's postdoctoral fellowship. Postdoctoral fellowships from the University of Pretoria and Claude Leon Foundation provided assistance to S.E. Equipment and running costs were provided by Idea Wild Fund, Professor V. Janik and the Nedbank Go Green Fund. International Master of Science in Marine Biodiversity and Conservation Programme.

Heat exchanger networks (HEN) in industrial heat recovery systems often consist of large and complex subsystems. Usually, such HENs are subject to variation in operating conditions, such as varying inlet conditions or changing heat capacity flow rates. Additionally, complexities such as stream splits and recycle loops are commonly present in industrial HENs. Therefore, extensive modelling and/or analytical calculations may be necessary when analyzing different retrofit proposals. Furthermore, retrofit opportunities in industrial heat recovery systems are often constrained by operability considerations, i.e. retrofit actions are supposed to have as little impact as possible on the production process to maintain the quality of the core product. In this work, a computational analysis tool is proposed for effective screening of HEN retrofit design proposals at an early stage in the design process. The proposed tool enables fast evaluation of the network’s response, i.e. temperatures and heat loads, when operating conditions change and/or operational settings are manipulated, and it is applicable for a wide range of HEN structures. The practical use of the analysis tool is demonstrated in a case study on the HENs of a large modern Kraft pulp mill.

Introduction Children with epilepsy report lower health-related quality of life (QOL) compared with healthy children and those with other chronic disorders. This study piloted the recently published Pediatric Quality of Life Inventory (PedsQL) Epilepsy Module (PedsQL-EM) in an ambulatory setting and studied epilepsy-related factors contributing to QOL in children with epilepsy. Methods Children with epilepsy aged 8–18 years who were ambulant and verbal were recruited from pediatric neurology clinics. Children and their caregivers completed age-appropriate versions of the PedsQL-EM (8–12 or 13–18 years) in the clinic waiting area. Treating neurologists completed medical questionnaires about their patients' epilepsy. Results We collected 151 parent-report and 127 self-report PedsQL-EMs. Administration time was 5–10 min with some children receiving assistance from the researcher. Mean age of children was 12.9+/-3.0, with 77 females (51%). Parents reported lower mean QOL scores across all subdomains compared with their children. Parents reported significantly lower QOL for children with earlier age at epilepsy onset, longer epilepsy duration, presence of seizures during the last month, more severe epilepsy, increased number of antiepileptic drugs (AEDs), and cognitive comorbidity. The same factors impacted on child self-reporting, but with more variability across subdomains. Conclusions The PedsQL-EM is an epilepsy-specific measure of QOL that is quick and easy to administer and is sensitive to the clinical factors reported to impact on QOL in pediatric epilepsy.

In Sweden, the iron and steel industry (ISI) is a major source of greenhouse gas (GHG) emissions. Most of the emissions result from the use of fossil reducing agents. Nevertheless, the use of fossi ...

TSA (total site analysis) has shown to be an efficient tool for identifying heat integration measures in industrial clusters, leading to the optimal design of utility systems and energy bill reduction. In order to justify investments, any proposed utility system must be shown to be able to operate in all configurations that an industrial cluster can encounter, especially those relating to varying heat demand. Previous TSAs have generally been carried out using yearly means of heat exchange loads or using scenarios corresponding to specific operation modes of the sites. While these have been useful for designing systems under normal conditions, they are not fit for evaluating minima and peaks in utility demand. Carrying out a TSA on each possible configuration of a cluster is not feasible from a computational and results analysis point of view. A method is therefore proposed to represent the variability of data over long periods in a reduced form in order to carry out engineering studies.A methodology is proposed to identify typical operating periods of an industrial cluster made up of several production units. This algorithm exploits a multi-objective optimisation to identify n periods that delimit typical operating modes or multiple profiles.A TSA was previously carried out on the Stenungsund petrochemical cluster in Sweden, leading to the design of a utility system to significantly reduce the overall energy consumption of the cluster. The solution proposes that a common utility system would decrease the hot utility demand from 124 MWth to 70 MWth. The multi-period analysis methodology is demonstrated by application to this case study in order to identify the resilience of the proposed solution when faced with variations in heat production and consumption. The multi-period analysis of the proposed utility system leads to the identification of a peak utility demand of 88 MWth rather than the previously identified 70 MWth. A Total Site Sensitivity Analysis leads to a better understanding of the contribution of each of the clusters units and feasibility of investments. © 2015 Elsevier Ltd.

The European process industry is facing major challenges to decrease production costs. One strategy to achieve this is by increasing energy efficiency. Single chemical processes are often well-integrated and the tools to target and design such measures are well developed. Site-wide heat integration based on total site analysis tools can be used to identify opportunities to further increase energy efficiency. However, the methodology has to be developed further in order to enable identification of practical heat integration measures in a systematic way. Designing site-wide heat recovery systems across an industrial cluster is complex and involves aspects apart from thermal process and utility flows. This work presents a method for designing a roadmap of heat integration investments based on total site analysis. The method is applied to a chemical cluster in Sweden. The results of the case study show that application of the proposed method can achieve up to 42% of the previously targeted hot utility savings of 129 MW. A roadmap of heat integration systems is suggested, ranging from less complex systems that achieve a minor share of the heat recovery potential to sophisticated, strongly interdependent systems demanding large investments and a high level of collaboration. (C) 2015 Elsevier Ltd. All rights reserved.

This study explored the impact of developmental stage on cognitive function in children with recently-diagnosed epilepsy. In keeping with a neurodevelopmental framework, skills in a critical developmental period were expected to be more vulnerable than those stable at the time of seizure onset. We studied children with early-onset (EO) symptomatic focal epilepsy (onset: 3–5 years; n = 18) and compared their performance with that of the group with late-onset (LO) epilepsy (onset: 6–8 years performance of; n = 8) on a range of cognitive tasks. Performance of both groups was compared with normative standards. ‘Critical’ and ‘stable’ classifications were based on developmental research. Nonparametric analyses revealed that skills in a critical developmental period for the group with EO epilepsy fell below normative standards (Phonological Processing: p = .007, Design Copying: p = .01, Visuomotor Precision:, p = .02) and fell below the performance of the group with LO epilepsy (Design Copying: p = .03, Visuomotor Precision: p = .03). There were no differences between the group with EO epilepsy and the group with LO epilepsy on measures of receptive vocabulary and memory, which were proposed to be in a stable developmental period across both groups. Auditory span, as measured by Word Order, was reduced for both the group with EO epilepsy (p = .02) and the group with LO epilepsy (p = .02) relative to normative standards, but the groups did not differ from each other. These results are consistent with a prolonged period of critical development for this skill. These findings support the notion that skills in a critical phase of development are particularly vulnerable following the onset of symptomatic focal epilepsy in childhood.

The present work discusses the potential and the economic feasibility of DH (district heating) delivery using industrial excess heat from a petrochemical cluster at the Swedish West Coast. Pinch Analysis was used for estimating the DH capacity targets and for estimating the cost of heat exchanger installation. A discounted cash flow rate of return of 10% was used as a criterion for identifying the minimum yearly DH delivery that should be guaranteed for a given DH capacity at different DH sales prices. The study was conducted for the current scenario in which no heat recovery is achieved between the cluster plants and for a possible future scenario in which 50% of the fuel currently used for heating purposes is saved by increasing the heat recovery at the site. The competition between excess heat export and local energy efficiency measures is also discussed in terms of CO2 emission consequences. The maximum capacity of DH delivery amounts today to around 235 MW, which reduces to 110 MW in the future scenario of increased site heat recovery. The results of our analysis show that feasible conditions exist that make DH delivery profitable in the entire capacity range.

This study investigates heat integrated production of FT (Fischer-Tropsch) crude, where excess heat from the FT crude plant is delivered to a typical Scandinavian pulp and paper mill that produces fine paper. The sizes of FT crude plants are quantified, when the amount of excess heat from the FT plant exactly matches the heating demand otherwise satisfied by the bark boiler at the mill, considering a number of development pathways at the mill, including various degrees of steam savings and biorefinery options, such as lignin extraction. Performance of integrated production is compared with that of an FT stand-alone plant on the basis of wood fuel-to-FT crude efficiency, GHG (greenhouse gas) emissions balances and FT crude production cost. The results show that there exists a heat integration opportunity for an FT crude plant ranging from 0 up to 350 MW (LHV) of wood fuel depending on the development pathway for the mill. The results indicate higher overall efficiency and a generally lower production cost for the heat integrated, co-located production. Heat integrated production has a larger potential to contribute to GHG emission mitigation, assuming a future generation of grid electricity emitting equal to or less than an NGCC (natural gas combined cycle) power plant. © 2013 Elsevier Ltd. All rights reserved.

Energy intensive industries, such as the bulk chemical industry, are facing major challenges and adopting strategies to face these challenges. This paper investigates options for clusters of chemical process plants to decrease their energy and emission footprints. There is a wide range of technologies and process integration opportunities available for achieving these objectives, including (i) decreasing fossil fuel and electricity demand by increasing heat integration within individual processes and across the total cluster site; (ii) replacing fossil feedstocks with renewables and biorefinery integration with the existing cluster; (iii) increasing external utilization of excess process heat wherever possible. This paper presents an overview of the use of process integration methods for development of chemical clusters. Process simulation, pinch analysis, Total Site Analysis (TSA) and exergy concepts are combined in a holistic approach to identify opportunities to improve energy efficiency and integrate renewable feedstocks within such clusters. The methodology is illustrated by application to a chemical cluster in Stenungsund on the West Coast of Sweden consisting of five different companies operating six process plants. The paper emphasizes and quantifies the gains that can be made by adopting a total site approach for targeting energy efficiency measures within the cluster and when investigating integration opportunities for advanced biorefinery concepts compared to restricting the analysis to the individual constituent plants. The holistic approach applied highlights the significant potential improvement to energy and emissions footprints that can be achieved when applying a total site approach.

Process cooling below ambient temperature is an energy demanding part of many chemical production processes. Compression refrigeration systems operating at very low temperatures consume a lot of high quality utility such as electricity or high pressure steam to drive the compressor units. In industrial process clusters with several processes operating at low temperatures, it is important to investigate opportunities for exchange of low-temperature energy between processes. This paper demonstrates how total site analysis and exergy analysis can be applied to target for shaft power and related hot utility savings for processes and utility systems operating below ambient temperature. Shaft power targeting by optimizing refrigerant use is conducted. In addition the methodology is extended for shaft power targeting in connection with site-wide heat recovery from cold process streams to generate sub-ambient utility. The methodology is illustrated through application to a case study of a chemical cluster. One chemical plant within the cluster operates two compression refrigeration systems at its steam cracker plant. The results of the case study indicate potential savings of 1.5 MW of shaft power by optimizing the use of refrigerant from the compression refrigeration system and additional 2.5 MW of shaft power by recovering refrigeration from two other sites located outside the cracker plant. In total this corresponds to 15% of the total shaft power consumption of the refrigeration systems. Economic evaluation of the proposed measures indicates a pay-back period of approximately 4 years.

The energy network in Luleå consists of the steel plant, heat and power production and district heating. Global system studies are necessary to avoid sub-optimization and to deliver energy and/or material efficiency. SSAB began work with global simulation models in 1978. After that several more specialized process integration tools have been tested and used: Mathematical programming using a MILP method, exergy analysis and Pinch analysis. Experiences and examples of results with the different methods are given and discussed. Mathematical programming has been useful to study problems involving the total system with streams of different types of energy and material and reaction between them. Exergy is useful to describe energy problems involving different types of energy, e.g. systematic analysis of rest energies. Pinch analysis has been used especially on local systems with streams of heat energy and heat exchange between them. Validerad; 2013; 20120413 (ysko)

In this paper performance assessment of second generation biofuel production using energy market scenarios and system-level performance indicators is proposed. During biofuel production a number of products and services can be co-generated while import of energy services (e.g. electricity and heat) in addition to the fuel supply may also be needed. This needs to be reflected by a well-defined performance indicator enabling a comparison between different process alternatives. A marginal production perspective is proposed in this study for the definition of a general energy performance indicator, recalculating all services to primary energy on a system level. The Energy Price and Carbon Balance Scenarios (ENPAC) tool developed at Chalmers is used for the definition of the energy system background. Thereby, a scenario-specific comparison of the processes’ thermodynamic, economic and carbon footprint performance is possible. The usefulness of the approach is illustrated for production of synthetic natural gas (SNG) from biomass. The shortcomings of common performance indicators are also discussed.

Blackliquorgasification (BLG) is being developed as an alternative technology for energy and chemical recovery in kraft pulp mills. This study compares BLG – with downstream production of DME (dimethyl ether) or electricity – with recovery boiler-based pulping biorefinery concepts for different types of mills. The comparison is based on profitability as well as CO2 emissions, using different future energy market scenarios. The possibility for carbon capture and storage (CCS) is considered. The results show that, if commercialised, BLG with DME production could be profitable for both market pulp mills and integrated pulp and paper mills in all energy market scenarios considered. Recovery boiler-based biorefinery concepts including extraction of lignin or solid biomass gasification with DME production could also be profitable for market and integrated mills, respectively. If the mill is located close to an infrastructure for CO2 collection and transportation, CCS significantly improves profitability in scenarios with a high CO2 emissions charge, for both combustion- and gasification-based systems. Concepts that include CCS generally show a large potential for reduction of global CO2 emissions. Few of the concepts without CCS achieve a significant reduction of CO2 emissions, especially for integrated mills.

Much of the current debate in ageing countries focuses on whether governments should increase investments in human capital. We address this issue by simulating the effects of additional education spending using an overlapping-generations model applied to Canada. In the context of population ageing, the results indicate that how the policy is funded has powerful impacts on the targeted outcomes. Higher education incentives may increase the rate of human capital accumulation and mitigate the negative effects of slowing labour force growth. However, the impact depends on the distortions implied by alternative tax instruments and the efficiency of public expenditures on education.

Introduction Based on the study of adults with brain insult, traditional localizationist views have argued that executive skills are primarily mediated by prefrontal cortex. It remains unclear whether a similar pattern of localization exists in childhood. Methods: To investigate this hypothesis, we compared the performance of children, aged 7–16 years, with radiological evidence of brain pathology. The sample was divided according to lesion location as follows: frontal pathology (n = 38), extra-frontal pathology (n = 20), generalized pathology (n = 21) and healthy controls (n = 40). Using a multidimensional model of executive function described by Anderson (2002) and Anderson, 1998 , Anderson et al., 2001c , Anderson et al., 2001d ), these groups were compared on a range of executive function domains including: attentional control, goal setting, cognitive flexibility, and information processing. Additional, non-executive measures were also administered. Results Contrary to adult lesion-based studies, there was little differentiation in executive processes between frontal and extra-frontal groups. Conclusions These results provide support for contemporary models which propose a distributed, but integrated neural network for executive skills, suggesting that the integrity of the entire brain is necessary for adequate executive functions in childhood. Further, focal lesions to any brain region during development may render children vulnerable to a range of executive deficits that would not normally be expected following similar pathology in adulthood.

This paper evaluates system aspects of biorefineries based on biomass gasification integrated with pulp and paper production. As a case the Billerud Karlsborg mill is used. Two biomass gasification concepts are considered: BIGDME (biomass integrated gasification dimethyl ether production) and BIGCC (biomass integrated gasification combined cycle). The systems analysis is made with respect to economic performance, global CO2 emissions and primary energy use. As reference cases. BIGDME and BIGCC integrated with district heating are considered. Biomass gasification is shown to be potentially profitable for the mill. The results are highly dependent on assumed energy market parameters, particularly policy support. With strong policies promoting biofuels or renewable electricity, the calculated opportunity to invest in a gasification-based biorefinery exceeds investment cost estimates from the literature. When integrated with district heating the BIGDME case performs better than the BIGCC case, which shows high sensitivity to heat price and annual operating time. The BIGCC cases show potential to contribute to decreased global CO2 emissions and energy use, which the BIGDME cases do not, mainly due to high biomass demand. As biomass is a limited resource, increased biomass use due to investments in gasification plants will lead to increased use of fossil fuels elsewhere in the system. Original Publication:Elisabeth Wetterlund, Karin Pettersson and Simon Harvey, Systems analysis of integrating biomass gasification with pulp and paper production - Effects on economic performance, CO2 emissions and energy use, 2011, ENERGY, (36), 2, 932-941.http://dx.doi.org/10.1016/j.energy.2010.12.017Copyright: Elsevier Science B.V., Amsterdam.http://www.elsevier.com/

Simultaneous EEG and functional MRI (EEG-fMRI) studies of focal epileptiform spikes commonly use the canonical haemodynamic response function (HRF) to model the blood-oxygenation-level-dependent (BOLD) response to these events. Support for the use of the canonical HRF has come from large studies that contain mixed cohorts of epilepsy syndromes and discharge types, and has demonstrated plausible epileptic localisation results in the majority of patients. Other studies, however, have reported that some patients show a BOLD response that differs markedly from a canonical HRF. Our aim in this study was to see if the BOLD response is well modelled by a canonical HRF in a homogeneous cohort of patients with benign epilepsy with centrotemporal spikes (BECTS), an idiopathic partial epilepsy with stereotypical centrotemporal spikes on the EEG. We studied eight well-characterised and typical BECTS patients and found that the shape of the average BOLD response was different to the canonical HRF. Furthermore, a localisation analysis using the group-average response provided increased sensitivity and specificity compared to the canonical HRF. Our findings suggest that the canonical HRF may not provide the best model for the BOLD response in some epilepsy syndromes or spike-types. In studies of homogeneous patient groups, therefore, localisation results may be improved by using a group-specific BOLD response.

Black liquor gasification (BLG) is currently being developed as an alternative technology for energy and chemical recovery at chemical pulp mills. This study examines how different assumptions regarding systems surrounding the pulp mill affect the CO2 emission balances for different BLG concepts. The syngas from the gasification process can be used for different applications; this study considers production of renewable motor fuels and electricity generation. Both a market pulp mill and an integrated pulp and paper mill are considered as host mill for the BLG plant. Furthermore, the consequences of limited availability of biomass are shown, i.e., increasing the use of biomass in a mill is not necessarily CO2-neutral. The results show that the potential to reduce CO2 emissions by introducing BLG is generally much higher for a market pulp mill than for an integrated pulp and paper mill. Electricity generation from the syngas is favoured when assuming high grid electricity CO2 emissions where as motor fuel production is favoured when assuming low grid electricity CO2 emissions. When considering the consequences of limited availability of biomass, the CO2 emission balances are strongly affected, in some cases changing the results from a decrease to an increase of the CO2 emissions.

The energy intensive industry can be a major contributor to CO2 emissions reduction, provided that appropriate investments are made. To assess profitability and net CO2 emissions reduction potential of such investments, predictions about future energy market conditions are needed. Energy market scenarios can be used to reflect different possible future energy market conditions. This paper presents a tool for creating consistent energy market scenarios adapted for evaluation of energy related investments in energy intensive industrial processes. Required user inputs include fossil fuel prices and costs associated with policy instruments, and the outputs are energy market prices and CO2 consequences of import/export of different energy streams (e.g. electric power and biomass fuel) from an industrial process site. The paper also presents four energy market scenarios for the medium-term future (i.e. around 2020) created using the tool.

This study explores the long-term impact of population ageing on labour supply and human capital investment in Canada, as well as the induced effects on productive capacity. The analysis is conducted with a dynamic computable overlapping generations model where in the spirit of Becker [Becker, Gary (1965), A theory of the allocation of time, The Economic Journal, Vol. 75, pp. 493–517.] and Heckman [Heckman, James (1976), A life-cycle model of earnings, learning and consumption, The Quarterly Journal of Economics, Vol. 84, pp. 511–544], leisure has a quality-time feature and labour supply and human capital investment decisions are endogenous. The role of human capital in the growth process is based on the framework used by Mankiw et al. [Mankiw, N. Gregory, Romer, David and Weil, David N. (1992), A contribution to the empirics of economic growth, Quarterly Journal of Economics, Vol. 107, no. 2, pp. 407–437]. The paper indicates that population ageing creates more opportunities for young individuals to invest in human capital and supply more skilled labour at middle age. Consequently, the reduction in labour supply of young adults initially lowers productive capacity and exacerbates the economic costs of population ageing. However, current and future middle-age cohorts are more skilled and work more, which eventually raises productive capacity and significantly lowers the cost of population ageing. Finally, these results suggest that the recent increase in the participation rate of older workers might be the beginning of a new trend that will amplify over the next decades.

Hypothalamic hamartoma (HH) is a congenital malformation of the hypothalamus that may be asymptomatic or manifest with precocious puberty or seizures. Gelastic seizures often begin early in life, even in the newborn period, being manifest by frequent attacks of inappropriate laughter resulting from seizure activity in the HH. The scalp electroencephalogram (EEG) is often normal in children with gelastic seizures, such that the diagnosis of epilepsy and the finding of a HH are often delayed. In a proportion of children with HH, there is an epileptic progression, in which complex partial seizures with frontal, temporal, and lateralized clinical features appear, usually with the appearance of focal slowing and epileptiform activity on the interictal EEG. Further progression may ensue with the appearance of tonic or atonic drop attacks, generalized tonic-clonic seizures, and epileptic spasms; rarely, infantile spasms may be the presenting seizure type. With the appearance of generalized seizures, the interictal EEG shows bilaterally synchronous and generalized epileptiform activity, often in abundance. The mechanism of this evolution is incompletely understood but neocortical seizure propagation and secondary epileptogenesis are believed to be important. Paralleling the development of the focal and generalized electroclinical manifestations in children with HH is usually slowing of development and the appearance of behavioral problems. Fortunately, many of these neurologic manifestations can be arrested, or reversed, with effective surgical treatment directed at the HH.

When gasified black liquor is used for hydrogen production, significant amounts of biomass must be imported. This paper compares two alternative options for producing hydrogen from biomass: (A) pulp-mill-integrated hydrogen production from gasified back liquor; and (B) stand-alone production of hydrogen from gasified biomass. The comparison assumes that the same amount of biomass that is imported in Alternative A is supplied to a stand-alone hydrogen production plant and that the gasified black liquor in Alternative B is used in a black liquor gasification combined cycle (BLGCC) CHP unit. The comparison is based upon equal amounts of black liquor fed to the gasifier, and identical steam and power requirements for the pulp mill. The two systems are compared on the basis of total CO2 emission consequences, based upon different assumptions for the reference energy system that reflect different societal CO2 emissions reduction target levels. Ambitions targets are expected to lead to a more CO2–lean reference energy system, in which case hydrogen production from gasified black liquor (Alternative A) is best from a CO2 emissions’ perspective, whereas with high CO2 emissions associated with electricity production, hydrogen from gasified biomass and electricity from gasified black liquor (Alternative B) is preferable.

While it is generally agreed that outcome following cerebral insult during childhood differs from that seen following similar pathology in adulthood, the specific relationship between timing of cerebral lesion and outcome, and the mechanism associated with observed neurobehavioral changes, remains controversial. Data from children with focal lesions suggests a non-linear relationship between age at injury and language function (e.g., Bates et al., 1999). With respect to executive function, animal models also demonstrate a non-linear relationship, and suggest that outcome is tightly linked to underlying neuronal changes (e.g., Kolb et al., 2000). Whether these models easily translate to humans, where brain morphology, cognitive function and environmental influences are more complex, is not clear. To date, focal lesion research in children has been restricted to individual case studies or, to samples of children with lesions to regions subsuming language function, or those who have undergone hemispherectomy for the treatment of intractable epilepsy. This study aimed to build on current knowledge, investigating executive function in 38 children with focal lesions involving prefrontal cortex. Aetiology and timing of lesions was diverse. Results are consistent with animal research suggesting a non-linear relationship between age at injury and outcome, with "critical periods" during development when the frontal lobes are particularly vulnerable to insult, and others when outcome is more optimal. Our findings indicate that children with prenatal lesions are at greatest risk of neurobehavioral deficits. Children with lesions sustained in middle childhood demonstrate least severe impairments across executive domains, possibly due to a period of peak synaptogenesis and dendritic arborization during this developmental stage, in keeping with animal models and research investigating frontal lobe development.

Hydrogen produced from renewable biofuel is both clean and CO2 neutral. This paper evaluates energy and net CO2 emissions consequences of integration of hydrogen production from gasified black liquor in a chemical pulp mill. A model of hydrogen production from gasified black liquor was developed and integration possibilities with the pulp mill's energy system were evaluated in order to maximize energy recovery. The potential hydrogen production is 59 000 tonnes per year if integrated with the KAM reference market pulp mill producing 630 000 Air dried tonnes (ADt) pulp/year. Changes of net CO2 emissions associated with modified mill electric power balance, biofuel import and end usage of the produced hydrogen are presented and compared with other uses of gasified black liquor such as electricity production and methanol production. Hydrogen production will result in the greatest reduction of net CO2 emissions and could reduce the Swedish CO2 emissions by 8% if implemented in all chemical market pulp mills. The associated increases of biofuel and electric power consumption are 5% and 1.7%, respectively.

Pulp mills use significant amounts of biofuels, both internal and purchased. Biofuels could contribute to reach greenhouse gas emission targets at competitive costs. Implementing process integration measures at a pulp mill in order to achieve pulp production with less use of energy (biofuels) has not only on-site consequences but also off-site consequences, such as substitution of fossil fuels elsewhere by the saved pulp mill biofuels, and less on-site electric power generation. In this paper a method, a linking model, is suggested to analyse pulp mill biofuel saving measures when carbon dioxide (CO2) external costs are internalised. The linking model is based on equilibrium economics and links information from CO2 constrained energy market future scenarios with process integration measures. Pulp mill economics and marginal energy market CO2 response are identified. In an applied study, four process integration measures at a Swedish pulp mill were analysed using five energy market future scenarios emanating from a Nordic energy model. The investigated investment alternatives for biofuel savings all result in positive net annual savings, irrespectively of the scenario used. However, CO2 emissions may increase or decrease depending on the future development of the Nordic energy market.

The goal of this study is to evaluate co-firing of gasified CO2 neutral biofuel in a retrofitted natural gas combined cycle (NGCC) combined heat and power (CHP) unit designed for natural gas operation. This type of situation may be particularly relevant if future CO2 abatement policies require that owners of natural gas fired CHP units reduce CO2 emissions. The study investigates the technical, economic and environmental performance of the CHP unit for different fractions of gasified biofuel in the unit’s fuel mix. The power plant simulation program GateCycle was used for plant performance evaluation. The calculations are based on a large size (about 300 MWe) NGCC CHP plant that is planned to be built on the West coast of Sweden, producing electricity and district heating for the local energy utility company. The results from this study show that it is possible to co-fire up to 40% (energy basis) biofuel product gas in the CHP unit. At this level of product gas co-firing, the unit’s electrical and total efficiencies decrease by approximately 2%-points, compared to operation on natural gas only. Global CO2 emissions can be reduced by approximately 400,000 tonnes/year. The total costs for the local utility company depend on the prevailing CO2 taxation rules, and on the assumed premium value of the renewable power produced. For the base case conditions assumed in the study, the cost of electricity (COE) for a natural gas fired NGCC CHP unit is 253 SEK/MWh, increasing to 306 SEK/MWh when a biofuel gasifier is integrated to the unit. A premium value for renewable electricity of 285 SEK/MWh is required for equal COE values to be achieved by the two systems.