Basins of attraction for cascading maps

We study a finite uni-directional array of "cascading" or "threshold coupled" chaotic maps. Such systems have been proposed for use in nonlinear computing and have been applied to classification problems in bioinformatics. We describe some of the attractors for such systems and prove general results about their basins of attraction. In particular, we show that the basins of attraction have infinitely many path components. We show that these components always accumulate at the corners of the domain of the system. For all threshold parameters above a certain value, we show that they accumulate at a Cantor set in the interior of the domain. For certain ranges of the threshold, we prove that the system has many attractors.Comment: 15 pages, 9 figures. To appear in International Journal of Bifurcations and Chao

Lessen en inzichten voor zbo-beleid

In dit artikel bespreken wij zes ons bekende rapporten, aan de hand van een aantal bestaande discussiepunten uit het zbo-beleid

Organiseren met beleid

Beleid komt tot stand binnen en wordt uitgevoerd door organisaties. Dit hoofdstuk gaat in op vraagstukken rondom het ontwerpen van organisaties, en op de vraag hoe de omgeving van organisaties doorwerkt in het ontwerp ervan

New Public Management in Europe

New Public Management (NPM) is the label which many academics have given to a series of reforms from the 1980s onwards, to improve the efficiency and performance of western governments and/or public sector organizations. Examples are the development of performance indicators and benchmarking, personnel reforms aimed at ‘normalising’ public sector employment on private sector models, placing executive bodies at arms’ length from ministries, establishing public private partnerships and introducing new management techniques and instruments. Continental European governments have adapted and re-interpreted many of the Anglo-American ideas underpinning the NPM, to adjust them to their own national politico-administrative contexts. As a consequence, reforms of the public sector may have the same labels in different countries but need not be the same in practice or in meaning; there is both convergence and divergence

Examining the efficacy of six published time-lapse imaging embryo selection algorithms to predict implantation to demonstrate the need for the development of specific, in-house morphokinetic selection algorithms.

OBJECTIVE: To study the efficacy of six embryo-selection algorithms (ESAs) when applied to a large, exclusive set of known implantation embryos. DESIGN: Retrospective, observational analysis. SETTING: Fertility treatment center. PATIENT(S): Women undergoing a total of 884 in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment cycles (977 embryos) between September 2014 and September 2015 with embryos cultured using G-TL (Vitrolife) at 5% O2, 89% N2, 6% CO2, at 37°C in EmbryoScope instruments. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Efficacy of each ESA to predict implantation defined using specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), area under the receiver operating characteristic curve (AUC), and likelihood ratio (LR), with differences in implantation rates (IR) in the categories outlined by each ESA statistically analyzed (Fisher's exact and Kruskal-Wallis tests). RESULT(S): When applied to an exclusive cohort of known implantation embryos, the PPVs of each ESA were 42.57%, 41.52%, 44.28%, 38.91%, 38.29%, and 40.45%. The NPVs were 62.12%, 68.26%, 71.35%, 76.19%, 61.10%, and 64.14%. The sensitivity was 16.70%, 75.33%, 72.94%, 98.67%, 51.19%, and 62.33% and the specificity was 85.83%, 33.33%, 42.33%, 2.67%, 48.17%, and 42.33%, The AUC were 0.584, 0.558, 0.573, 0.612, 0.543, and 0.629. Two of the ESAs resulted in statistically significant differences in the embryo classifications in terms of IR. CONCLUSION(S): These results highlight the need for the development of in-house ESAs that are specific to the patient, treatment, and environment. These data suggest that currently available ESAs may not be clinically applicable and lose their diagnostic value when externally applied

Preliminary investigation of the prevalence and implantation potential of abnormal embryonic phenotypes assessed using time-lapse imaging.

This retrospective, single site observational study aimed to delineate five abnormal embryonic developmental phenotypes, assessing their prevalence, development potential and suitability for inclusion in embryo selection models for IVF. In total, 15,819 embryos from 4559 treatment cycles cultured in EmbryoScope® incubators between January 2014 and January 2016 were included. Time-lapse images were assessed retrospectively for five abnormal embryo phenotypes: direct cleavage, reverse cleavage, absent cleavage, chaotic cleavage and cell lysis. The prevalence of each abnormal phenotype was assessed. Final embryo disposition, embryo quality and implantation rate were determined and compared with a control embryo cohort. The collective prevalence for the five abnormal phenotypes was 11.4%; chaotic cleavage and direct cleavage together constituted 9.7%. Implantation rates were 17.4%, 0%, 25%, 2.1% and 0% for direct, reverse, absent, chaotic cleavage and cell lysis, respectively. The overall implantation rate for all abnormal embryos with known implantation status was significantly lower compared with the control population (6.9% versus 38.7%, P < 0.0001). The proportion of good quality embryos in each category of abnormal cleavage remained below 25%. Embryos exhibiting an abnormal phenotype may have reduced developmental capability, manifested in both embryo quality and implantation potential, when compared with embryos of normal phenotype

Implications from Responsible Human-Robot Interaction with Anthropomorphic Service Robots for Design Science

Accelerated by the COVID-19 pandemic, anthropomorphic service robots are continuously penetrating various domains of our daily lives. With this development, the urge for an interdisciplinary approach to responsibly design human-robot interaction (HRI), with particular attention to human dignity, privacy, compliance, and transparency, increases. This paper contributes to design science, in developing a new artifact, i.e., an interdisciplinary framework for designing responsible HRI with anthropomorphic service robots, which covers the three design science research cycles. Furthermore, we propose a multi-method approach by applying this interdisciplinary framework. Thereby, our finding offer implications for designing HRI in a responsible manner

Comparison of methods to identify and characterize Post-COVID syndrome using electronic health records and questionnaires

Background: Some of those infected with coronavirus suffer from post-COVID syndrome (PCS). However, an uniform definition of PCS is lacking, causing uncertainty about the prevalence and nature of this syndrome. We aim to improve understanding by operationalizing different definitions of PCS in different data sources and describing features and clinical subtypes.Methods: We use different methods and data sources. First, a cohort with electronic health records (EHR) from general practices (GPs) and GP out-of-hours-services combined with sociodemographic data for n≈1.000.000 individuals. Second, questionnaires among n=276 individuals who had been infected with coronavirus. Using both data sources, we operationalized definitions of PCS to calculate frequency and characteristics. In a subgroup of the EHR data we conducted community detection analyses to explore possible clinical subtypes of PCS.Results: The frequency of PCS ranged from 15-33%, depending on the method and data source. Across all methods and definitions, the mean age of individuals with PCS was around 53 years and they were more often female. There were small sex differences in the type of symptoms and overall symptoms were persistent for 6 months. Exploratory network analysis revealed three possible clinical subtypes.Discussion: We showed that frequency rates of post-COVID syndrome differ between methods and data sources, but characteristics of the affected individuals are quite stable. Overall, PCS is a heterogeneous syndrome affecting a significant group of individuals who need adequate care. Future studies should focus on care trajectories and qualitative measures such as experiences and quality of life of individuals living with PCS