1,298 research outputs found

    Energy efficiency considerations in integrated IT and optical network resilient infrastructures

    Get PDF
    The European Integrated Project GEYSERS - Generalised Architecture for Dynamic Infrastructure Services - is concentrating on infrastructures incorporating integrated optical network and IT resources in support of the Future Internet with special emphasis on cloud computing. More specifically GEYSERS proposes the concept of Virtual Infrastructures over one or more interconnected Physical Infrastructures comprising both network and IT resources. Taking into consideration the energy consumption levels associated with the ICT today and the expansion of the Internet in size and complexity, that incurring increased energy consumption of both IT and network resources, energy efficient infrastructure design becomes critical. To address this need, in the framework of GEYSERS, we propose energy efficient design of infrastructures incorporating integrated optical network and IT resources, supporting resilient end-to-end services. Our modeling results quantify significant energy savings of the proposed solution by jointly optimizing the allocation of both network and IT resources

    Onderzoek naar de trekvissoorten in het Schelde-estuarium. Voortplantings-en opgroeihabitat van rivierprik en fint

    Get PDF
    Migratory fish such as river lamprey and twaite shad are important indicators of ecosystem functioning. Over the past century, most migratory fish have disappeared from the river Scheldt due to human impacts. The previous study on migratory fishes in the Scheldt showed however that most species show the first signs of recovery (Stevens et al., 2009). For both river lamprey and twaite shad there are strong indications that they reproduce in the Scheldt. However, the spawning and nursery habitats of both species are unknown and it is unclear whether the preconditions for a sustainable recovery are met. The spawning and nursery habitat of river lamprey can be located through targeted sampling of the larvae in the sediment. Sampling with fyke nets showed that adult river lamprey migrate mainly to the Bovenschelde and Zwalmbeek. In both rivers a number of locations were selected, which are, according to the literature, expected to be suitable habitats for the larvae of river lamprey. Wadable sites were sampled with a specially designed sediment pump and the deeper sites with a Van Veen grab. In neither of these rivers, however, river lamprey larvae could be found and no spawning sites could be identified. Possible reasons for the lack of larvae in the samples are (1) that no suitable larval habitat is present in the studied areas, (2) that the larval density in the investigated habitats is low and hence sampling frequency should be increased, (3) that the River Bovenschelde and the River Zwalm are not the main spawning grounds for river lamprey in the Scheldt. Telemetry of adult river lamprey could be a possible solution to locate the spawning grounds. In order to improve the reproduction and survival of river lamprey in the River Bovenschelde, the migration barriers in the Scheldt and its tributaries should be cleared and sufficient larval habitat should be availability. Larval habitat could be created in the River Zwalm and other tributaries through the restoration of natural banks. In addition, mud and sand banks in the Bovenschelde should be protected as much as possible as potential larval habitat.The population of twaite shad in the Scheldt is too small to identify the critical habitats by sampling in the field. Therefore, a habitat suitability model for spawning and larval shad was constructed based on literature data. Hereto, we first selected the environmental variables that determine habitat suitability. Next, for each variable the tolerance range was determined. Finallly, the variables were combined using fuzzy logic in order to determine the degree of suitability of a habitat. The model predicts the presence of suitable spawning habitat in the Upper Zeeschelde, upstream of the River Durme. Later in the season, when the water temperature rises, suitable spawning habitat is also present in the Rivers Kleine Nete and Grote Nete. Suitable habitat for larval shad is located mainly in the Upper Zeeschelde upstream Rupelmonde and in the River Rupel. Spawning of twaite shad takes place in the main channel and during their ontogeny the larvae migrate to the edges of the main channel and to side channels.Therefore, in areas with suitable spawning and larval habitat, both the main and side channels need protection. In particular mudflats, sand flats and subtidal low dynamic habitats should be safeguarded. Dredging of these habitats thus mortgages the recovery of the twaite shad population in the Scheldt. The oxygen concentration in the estuary has been greatly improved in recent years.However, in summer a low-oxygen zone in the freshwater area persists, comprising the upstream migration of adults and the survival of larvae. Periodic hypoxic conditions should therefore be avoided and a minimum oxygen content of 5 mg / l is essential for both adults and larvae. During the last century, hydrodynamics in the estuary has increased markedly. As a result, larvae have more difficulties in maintaining their position in suitable habitat. Actions that increase the river/tidal flow or eliminate local retention areas should therefore be avoided

    Trends in community response and long term outcomes from paediatric cardiac arrest:A retrospective observational study

    Get PDF
    AIM: This study aimed to investigate trends over time in pre-hospital factors for pediatric out-of-hospital cardiac arrest (pOHCA) and long-term neurological and neuropsychological outcomes. These have not been described before in large populations.METHODS: Non-traumatic arrest patients, 1 day-17 years old, presented to the Sophia Children's Hospital from January 2002 to December 2020, were eligible for inclusion. Favorable neurological outcome was defined as Pediatric Cerebral Performance Categories (PCPC) 1-2 or no difference with pre-arrest baseline. The trend over time was tested with multivariable logistic and linear regression models with year of event as independent variable.FINDINGS: Over a nineteen-year study period, the annual rate of long-term favorable neurological outcome, assessed at a median 2·5 years follow-up, increased significantly (OR 1·10, 95%-CI 1·03-1·19), adjusted for confounders. Concurrently, annual automated external defibrillator (AED) use and, among adolescents, initial shockable rhythm increased significantly (OR 1·21, 95% CI 1·10-1·33 and OR 1·15, 95% CI 1·02-1·29, respectively), adjusted for confounders. For generalizability purposes, only the total intelligence quotient (IQ) was considered for trend analysis of all tested domains. Total IQ scores and bystander basic life support (BLS) rate did not change significantly over time.INTERPRETATION: Long-term favorable neurological outcome, assessed at a median 2·5 years follow-up, improved significantly over the study period. Total IQ scores did not significantly change over time. Furthermore, AED use (OR 1·21, 95%CI 1.10-1·33) and shockable rhythms among adolescents (OR1·15, 95%CI 1·02-1·29) increased over time.</p

    An experimental evaluation of the State Adult Attachment Measure: the influence of attachment primes on the content of state attachment representations

    Get PDF
    Attachment theory predicts cross-contextual stability of attachment representations, but research findings are rather mixed. Recently, it has been suggested that these mixed findings reflect the existence of both state and trait attachment components. The development of the State Adult Attachment Measure (SAAM) has enabled an investigation of this hypothesis. The current study aimed to evaluate the extent to which the SAAM is a useful instrument for studying such state attachment hypotheses. For this purpose, a two-week longitudinal study investigated whether the manipulation of the temporal accessibility of different attachment contents activates different within-person attachment representations. The impact of attachment primes before re-administering the SAAM was investigated in 268 participants. Results showed that the SAAM was meaningfully related to evaluations of self and attachment figures. Moreover, activation of different attachment contexts influenced state attachment towards partners as primary attachment figures. The results provide support for the SAAM as a measure of state attachment towards partners, but data on parent attachment were less straightforward. In all, the current study provided support for contemporary models of attachment as comprising both trait-like stability and context-dependent variability in attachment state

    Sudden cardiac arrest in infants and children:proposal for a diagnostic workup to identify the etiology. An 18-year multicenter evaluation in the Netherlands

    Get PDF
    Sudden cardiac arrest (SCA) studies are often population-based, limited to sudden cardiac death, and excluding infants. To guide prevention opportunities, it is essential to be informed of pediatric SCA etiologies. Unfortunately, etiologies frequently remain unresolved. The objectives of this study were to determine paediatric SCA etiology, and to evaluate the extent of post-SCA investigations and to assess the performance of previous cardiac evaluation in detecting conditions predisposing to SCA. In a retrospective cohort (2002–2019), all children 0–18 years with out-of-hospital cardiac arrest (OHCA) referred to Erasmus MC Sophia Children's Hospital or the Amsterdam UMC (tertiary-care university hospitals), with cardiac or unresolved etiologies were eligible for inclusion. SCA etiologies, cardiac and family history and etiologic investigations in unresolved cases were assessed. The etiology of arrest could be determined in 52% of 172 cases. Predominant etiologies in children ≥ 1 year (n = 99) were primary arrhythmogenic disorders (34%), cardiomyopathies (22%) and unresolved (32%). Events in children &lt; 1 year (n = 73) were largely unresolved (70%) or caused by cardiomyopathy (8%), congenital heart anomaly (8%) or myocarditis (7%). Of 83 children with unresolved etiology a family history was performed in 51%, an autopsy in 51% and genetic testing in 15%. Pre-existing cardiac conditions presumably causative for SCA were diagnosed in 9%, and remained unrecognized despite prior evaluation in 13%. Conclusion: SCA etiology remained unresolved in 83 of 172 cases (48%) and essential diagnostic investigations were often not performed. Over one-fifth of SCA patients underwent prior cardiac evaluation, which did not lead to recognition of a cardiac condition predisposing to SCA in all of them. The diagnostic post-SCA approach should be improved and the proposed standardized pediatric post-SCA diagnostics protocol may ensure a consistent and systematic evaluation process increasing the diagnostic yield. What is Known: • Arrests in infants remain unresolved in most cases. In children &gt; 1 year, predominant etiologies are primary arrhythmia disorders, cardiomyopathy and myocarditis. • Studies investigating sudden cardiac arrest are often limited to sudden cardiac death (SCD) in 1 to 40 year old persons, excluding infants and successfully resuscitated children. What is New: • In patients with unresolved SCA events, the diagnostic work up was often incompletely performed. • Over one fifth of victims had prior cardiac evaluation before the arrest, with either a diagnosed cardiac condition (9%) or an unrecognized cardiac condition (13%). Graphical Abstract: [Figure not available: see fulltext.].</p
    • …
    corecore