The potential of mathematical picture books: a systematic analysis of their domain-specific picture book features

Studies in the domain of early literacy and recently also mathematics point to the potential of picture book reading (PBR) activities for children’s early literacy resp. mathematical development. Contrasting the domain of early literacy, the contribution of picture book features to the effectiveness of PBR activities in the domain of mathematics is hardly studied. To increase our understanding of the topic, we systematically analysed the domain-specific features of 100 mathematical picture books. Our analyses pointed to the presence of features that previous studies assume to support and to hinder early mathematical development (Ward et al., 2017). These findings complement previous findings based on English mathematical picture books from the U.S. and offer important insights for future studies and educational practice

Stratum Corneum Lipid Composition and Structure in Cultured Skin Substitutes is Restored to Normal after Grafting onto Athymic Mice

Restoration of an epidermal barrier is a definitive requirement for wound closure. Cultured skin substitutes grafted onto athymic nude mice were used as a model for a long-term study of stratum corneum barrier lipid metabolism and organization. Samples of stratum corneum collected after 12 and 21 d in vitro and 6, 11, and 24 mo postgrafting were examined for their lipid and fatty acid composition, and their lipid organization and structure using electron microscopy and small angle X-ray diffraction, respectively. All of these methods confirm the impaired barrier function of cultured skin substitutes in vitro, as judged from the deviations in lipid composition and from poor organization of the stratum corneum lipids that show no lamellar structure. At 6 mo postgrafting, the total stratum corneum lipid profiles of the epidermal grafts is close to that of the human stratum corneum with the exception of the presence of mouse specific lipids. The increase of ceramides 4–7 in cultured skin substitutes after grafting indicates restored activity of processes involved in the hydroxylation of fatty acids and sphingoid bases. Conversely, the ceramide profile still reveals some abnormalities (elevated content of ceramide 2 and slightly lower content of ceramide 3) and the content of long-chain fatty acids remains below its physiologic level at 6 mo postgrafting, but normalizes by 2 y postgrafting. The ultramicroscopic observations revealed the formation of lamellar extracellular lipid domains by 4 mo postgrafting. Despite these findings, the X-ray diffraction showed differences in the diffraction pattern at 2 y after grafting, suggesting that the organization of stratum corneum lipids in all epidermal grafts differs from that of the native skin. Journal of Investigative Dermatology Symposium Proceedings 3:114–120, 199

Antegrade balloon dilatation as a treatment option for posttransplant ureteral strictures: Case series of 50 patients

Objectives: The aim of this study was to investigate the effects of antegrade balloon dilatation on ureteral strictures that developed after kidney transplant. Materials and Methods: The hospital databases of the Erasmus Medical Center (Rotterdam, The Netherlands) and the Academic Medical Center (Amsterdam, The Netherlands) were retrospectively screened for patients who underwent balloon dilatation after kidney transplant. Balloon dilatation was technically successful whenever it was able to pass the strictured segment with the guidewire followed by balloon inflation; the procedure was clinically successful if no further interventions (for example, surgical revision of the ureteroneocystostomy or prolonged double J placement) were necessary. Results: Fifty patients (2.4%) of 2075 kidney transplant recipients underwent antegrade balloon dilatation because of urinary outflow obstruction. Median time between transplant and balloon dilatation was 3 months (range, 0-139 mo). In 43 patients (86%), balloon dilatation was technically successful. In the remaining 7 patients (14%), it was impossible to pass the strictured segment with the guidewire. In 20 of 43 patients (47%) having a technically successful procedure, the procedure was also clinically successful, with median follow-up after balloon dilatation of 35.5 months (range, 0-102 mo). We did not identify any patient o

Independent risk factors for urological complications after deceased donor kidney transplantation

Urological complications after kidney transplantation are mostly related to the ureteroneocystostomy, often requiring interventions with additional costs, morbidity and mortality. Our aim was to assess risk factors for urological complications in deceased donor kidney transplantation. Between January 2000 and December 2011, 566 kidney transplantations were performed with deceased donor kidneys. Recipients were divided in a group with, and a group without urological complications, defined as the need for a percutaneous nephrostomy catheter or surgical revision of the ureteroneocystostomy. Univariate and multivariate analyses were performed. Univariate analysis showed increased number of male donors (p = 0.041), male recipients (p = 0.002), pre-emptively transplanted recipients (p = 0.007), and arterial reconstructions (p = 0.004) in the group with urological complications. Less urological complications occurred in recipients on hemodialysis (p = 0.005). More overall surgical interventions (p<0.001), surgical site infections (p = 0.042), urinary tract infections (p<0.001) and lymphoceles (p<0.001) occurred in the group with urological complications. Multivariate analysis showed that male recipients (p = 0.010) and arterial reconstructions (p = 0.019) were independent risk factors. No difference was found between both groups in patient or graft survival. In conclusion, recipient male gender and arterial reconstruction are independent risk factors for urological complications after deceased donor kidney transplantation. Nevertheless, graft and recipient survival is not different between both groups

Model simulations on the long-term dispersal of 137Cs released into the Pacific Ocean off Fukushima

A sequence of global ocean circulation models, with horizontal mesh sizes of 0.5°, 0.25° and 0.1°, are used to estimate the long-term dispersion by ocean currents and mesoscale eddies of a slowly decaying tracer (half-life of 30 years, comparable to that of 137Cs) from the local waters off the Fukushima Dai-ichi Nuclear Power Plants. The tracer was continuously injected into the coastal waters over some weeks; its subsequent spreading and dilution in the Pacific Ocean was then simulated for 10 years. The simulations do not include any data assimilation, and thus, do not account for the actual state of the local ocean currents during the release of highly contaminated water from the damaged plants in March–April 2011. An ensemble differing in initial current distributions illustrates their importance for the tracer patterns evolving during the first months, but suggests a minor relevance for the large-scale tracer distributions after 2–3 years. By then the tracer cloud has penetrated to depths of more than 400 m, spanning the western and central North Pacific between 25°N and 55°N, leading to a rapid dilution of concentrations. The rate of dilution declines in the following years, while the main tracer patch propagates eastward across the Pacific Ocean, reaching the coastal waters of North America after about 5–6 years. Tentatively assuming a value of 10 PBq for the net 137Cs input during the first weeks after the Fukushima incident, the simulation suggests a rapid dilution of peak radioactivity values to about 10 Bq m−3 during the first two years, followed by a gradual decline to 1–2 Bq m−3 over the next 4–7 years. The total peak radioactivity levels would then still be about twice the pre-Fukushima values

Identifying major civil engineering research influencers and topics using social network analysis

This paper focused on applying social network analysis techniques to co�authorship network in order to discover the influencers in Civil engineering research field in Nigeria. It further applies the Latent Dirichlet allocation (LDA) algorithm to uncover the major research topics in this field. The research used 663 publications downloaded from the Scopus database, with the year of publication ranging from 1968 to 2018, using Nigeria as the case study, Civil and Structural engineering as the field of research. The study was carried out using the centrality measures in network analysis such as degree centrality, closeness centrality, and betweenness centrality for co-authorship network analysis of authors and text mining using the LDA algorithm to discover the research focus of the authors. Also, the relationship between the centrality measures and authors’ performance, measured in terms of citation was investigated using regression analysis. The results showed that there was a significantly positive relationship with betweenness centrality and closeness centrality for performance, but a negative relationship with degree centrality. Also the topics discovered using the LDA algorithm helped to reveal the major focus of Civil Engineering research in Nigeria. In conclusion, it is recommended that based on the co-authorship network of civil engineering research in Nigeria, which wa