Scaling properties of European research units.
Ontology highlight
ABSTRACT:
SUBMITTER: Jamtveit B
PROVIDER: S-EPMC2714277 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:The organization in brain networks shows highly modular features with weak inter-modular interaction. The topology of the networks involves emergence of modules and sub-modules at different levels of constitution governed by fractal laws that are signatures of self-organization in complex networks. The modular organization, in terms of modular mass, inter-modular, and intra-modular interaction, also obeys fractal nature. The parameters which characterize topological properties of brain networks follow one parameter scaling theory in all levels of network structure, which reveals the self-similar rules governing the network structure. Further, the calculated fractal dimensions of brain networks of different species are found to decrease when one goes from lower to higher level species which implicates the more ordered and self-organized topography at higher level species. The sparsely distributed hubs in brain networks may be most influencing nodes but their absence may not cause network breakdown, and centrality parameters characterizing them also follow one parameter scaling law indicating self-similar roles of these hubs at different levels of organization in brain networks. The local-community-paradigm decomposition plot and calculated local-community-paradigm-correlation co-efficient of brain networks also shows the evidence for self-organization in these networks.
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Project description:Understanding natural climate variability is essential for assessments of climate change. This is reflected in the scaling properties of climate records. The scaling exponents of the interglacial and the glacial climates are fundamentally different. The Holocene record is monofractal, with a scaling exponent H?0.7. On the contrary, the glacial record is multifractal, with a significantly higher scaling exponent H?1.2, indicating a longer persistence time and stronger nonlinearities in the glacial climate. The glacial climate is dominated by the strong multi-millennial Dansgaard-Oeschger (DO) events influencing the long-time correlation. However, by separately analysing the last glacial maximum lacking DO events, here we find the same scaling for that period as for the full glacial period. The unbroken scaling thus indicates that the DO events are part of the natural variability and not externally triggered. At glacial time scales, there is a scale break to a trivial scaling, contrasting the DO events from the similarly saw-tooth-shaped glacial cycles.
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Project description:The motion of social insects is often used as a paradigmatic example of complex adaptive dynamics arising from decentralized individual behaviour. In this paper, we revisit the topic of the ruling laws behind the burst of activity in ants. The analysis, done over previously reported data, reconsiders the causation arrows, proposed at individual level, not finding any link between the duration of the ants' activity and their moving speed. Secondly, synthetic trajectories created from steps of different ants demonstrate that a Markov process can explain the previously reported speed shape profile. Finally, we show that as more ants enter the nest, the faster they move, which implies a collective property. Overall, these results provide a mechanistic explanation for the reported behavioural laws, and suggest us a formal way to further study the collective properties in these scenarios.
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Project description:BackgroundOrganizational context plays a central role in shaping the use of research by healthcare professionals. The largest group of professionals employed in healthcare organizations is nurses, putting them in a position to influence patient and system outcomes significantly. However, investigators have often limited their study on the determinants of research use to individual factors over organizational or contextual factors.MethodsThe purpose of this study was to examine the determinants of research use among nurses working in acute care hospitals, with an emphasis on identifying contextual determinants of research use. A comparative ethnographic case study design was used to examine seven patient care units (two adult and five pediatric units) in four hospitals in two Canadian provinces (Ontario and Alberta). Data were collected over a six-month period by means of quantitative and qualitative approaches using an array of instruments and extensive fieldwork. The patient care unit was the unit of analysis. Drawing on the quantitative data and using correspondence analysis, relationships between various factors were mapped using the coefficient of variation.ResultsUnits with the highest mean research utilization scores clustered together on factors such as nurse critical thinking dispositions, unit culture (as measured by work creativity, work efficiency, questioning behavior, co-worker support, and the importance nurses place on access to continuing education), environmental complexity (as measured by changing patient acuity and re-sequencing of work), and nurses' attitudes towards research. Units with moderate research utilization clustered on organizational support, belief suspension, and intent to use research. Higher nursing workloads and lack of people support clustered more closely to units with the lowest research utilization scores.ConclusionModifiable characteristics of organizational context at the patient care unit level influences research utilization by nurses. These findings have implications for patient care unit structures and offer beginning direction for the development of interventions to enhance research use by nurses.
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Project description:To improve quality and to overcome the wide discrepancies in stroke care both within- and between European countries, the European Stroke Organisation Executive Committee initiated in 2007 activities to establish certification processes for stroke units and stroke centres. The rapidly expanding evidence base in stroke care provided the mandate for the European Stroke Organisation Stroke Unit-Committee to develop certification procedures for stroke units and stroke centres with the goals of setting standards for stroke treatment in Europe, improving quality and minimising variation. The purpose of this article is to present the certification criteria and the auditing process for stroke units and stroke centres that aim to standardise and harmonise care for stroke patients, and hence become members of the European Stroke Organisation Stroke Unit and Stroke Centre network. Standardised application forms and guidelines for national and international auditors have been developed and updated by members of the European Stroke Organisation Stroke Unit-Committee. Key features are availability of trained personnel, diagnostic equipment, acute treatment and collaboration with other stroke-caregivers. After submission, the application is reviewed by one national and two international auditors. Based on their reports, the Stroke Unit-Committee will make a final decision. Validating on-site visits for a subset of stroke units and stroke centres are planned. We herein describe a novel, European Stroke Organisation-based online certification process of stroke units and stroke centres. This is a major step forward towards high-quality stroke care across Europe. The additional value by connecting high-quality European Stroke Organisation Stroke Unit and Stroke Centre is facilitation of future collaboration and research activities, enabling building and maintenance of a high-quality stroke care network in Europe.
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Project description:Advances in stem cell biology have raised legal challenges to the patentability of stem cells and any derived technologies and processes. In 1999, Oliver Brüstle was granted a patent for the generation and therapeutic use of neural cells derived from human embryonic stem cells (hESCs). The patent was challenged and put before the European Court of Justice, which ruled that inventions involving the prior destruction of human embryos cannot be patented. The legal maneuvering around this case demonstrates that the future of stem cell-based patents in Europe remains unsettled. Furthermore, owing to the European Court's broad definition of hESC as 'any cell that is capable of commencing development into a human being,' novel technologies that could eliminate the need for hESCs, such as induced pluripotent stem cells (iPSCs), are at risk of being included under the same ruling. Advances in the in vitro development of germ cells from pluripotent stem cells may one day provide a direct developmental path from iPSC to oocyte and sperm, and, according to the European Court's reasoning, legally equate iPSCs with human embryos. In this review, we will briefly discuss the Brüstle v Greenpeace case and the implications of the European Court of Justice's ruling. We will identify potential risks for stem cell research and future therapeutics resulting from the broad legal definition of the human embryo. Finally, we will broach the current legal landscape, as this broad definition has also created great uncertainty about the status of human iPSCs.
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