Arterio-ureteral fistula:a nationwide cross-sectional questionnaire analysis

PURPOSE: Arterio-ureteral fistula (AUF) is an uncommon diagnosis, but potentially lethal. Although the number of reports has increased over the past two decades, the true incidence and contemporary urologists’ experience and approach in clinical practice remains unknown. This research is conducted to provide insight in the incidence of AUF in The Netherlands, and the applied diagnostic tests and therapeutic approaches in modern practice. METHODS: A nationwide cross-sectional questionnaire analysis was performed by sending a survey to all registered Dutch urologists. Data collection included information on experience with patients with AUF; and their medical history, diagnostics, treatment, and follow-up, and were captured in a standardized template by two independent reviewers. Descriptive statistics were used. RESULTS: Response rate was 62% and 56 AUFs in 53 patients were reported between 2003 and 2018. The estimated incidence of AUF in The Netherlands in this time period is 3.5 AUFs per year. Hematuria was observed in all patients; 9% intermittent microhematuria, and 91% presenting with, or building up to massive hematuria. For the final diagnosis, angiography was the most efficient modality, confirming diagnosis in 58%. Treatment comprised predominantly endovascular intervention. CONCLUSION: The diagnosis AUF should be considered in patients with persistent intermittent or massive hematuria. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00345-021-03910-3

Enhancing the Social Capital of Learning Communities by Using an Ad Hoc Transient Communities Service

Fetter, S., Berlanga, A. J., & Sloep, P. B. (2009). Enhancing the Social Capital of Learning Communities by Using an Ad Hoc Transient Communities Service. In M. Spaniol, Q. Li, R. Klamma & R. W. H. Lau (Eds.), Proceedings of the 8th International Conference Advances in Web-based Learning - ICWL 2009 (pp. 150-157). August, 19-21, 2009, Aachen, Germany. Lecture Notes in Computer Science 5686; Berlin, Heidelberg: Springer-Verlag.In online learning, communities can help to enhance learning. However, because of the dynamic nature of communities, attaining and sustaining these communities can be difficult. One aspect that has an influence on, and is influenced by these dynamics is the social capital of a community. Features of social capital are the social network structure, the sense of belonging and, the support received and provided. It is hypothesized that these features can be improved by using Ad Hoc Transient Communities (AHTCs). Through an AHTC learners are brought together for a specific, learning-related goal (‘ad hoc’) and for only a limited amount of time (‘transience’). To test whether the use of AHTCs has a positive influence on the social capital, a learner support service which enables the use of AHTCs is proposed. Furthermore, requirements, pre-requisites, and future research are discussed.The work on this publication has been sponsored by the TENCompetence Integrated Project that is funded by the European Commission's 6th Framework Programme, priority IST/Technology Enhanced Learning. Contract 027087 [http://www.tencompetence.org

Nest-site competition between bumblebees (Bombidae), social wasps (Vespidae) and cavity-nesting birds in Britain and the Western Palearctic

Capsule: There is no evidence of widespread significant nest-site competition in Britain or the Western Palearctic between cavity-nesting birds and bumblebees or social wasps. Aims: To investigate competition between cavity-nesting birds and bumblebees and wasps, particularly the range-expanding Tree Bumblebee, Saxon Wasp and European Hornet in Britain, and review evidence throughout the Western Palearctic. Methods: We compared field data from English and Polish studies of tits and woodpeckers breeding in nest-boxes and/or tree holes to assess nest-site competition with bumblebees and wasps. We reviewed the literature quantifying nest-site competition between birds and these insects in the Western Palearctic. Results: Bumblebees and wasps are capable of usurping small passerines from nests. In England, these insects commandeered a mean annual 4.1% of tit nests initiated in nest-boxes; occurrence of hornets showed a long-term increase, but not other wasps or bumblebees. Across the Western Palearctic, insect occupation of nest-boxes was generally low, and was lower in England than in Poland. No insects were discovered in tree cavities, including those created by woodpeckers (Picidae). Conclusion: Nest-site competition between cavity-nesting birds and bumblebees and wasps appears to be a ‘nest-box phenomenon’, which may occasionally interfere with nest-box studies, but appears negligible in natural nest-sites

Tropical and subtropical cloud transitions in weather and climate prediction models: The GCSS/WGNE pacific cross-section intercomparison (GPCI)

International audienceA model evaluation approach is proposed in which weather and climate prediction models are analyzed along a Pacific Ocean cross section, from the stratocumulus regions off the coast of California, across the shallow convection dominated trade winds, to the deep convection regions of the ITCZ-the Global Energy and Water Cycle Experiment Cloud System Study/Working Group on Numerical Experimentation (GCSS/WGNE) Pacific Cross-Section Intercomparison (GPCI). The main goal of GPCI is to evaluate and help understand and improve the representation of tropical and subtropical cloud processes in weather and climate prediction models. In this paper, a detailed analysis of cloud regime transitions along the cross section from the subtropics to the tropics for the season June-July-August of 1998 is presented. This GPCI study confirms many of the typical weather and climate prediction model problems in the representation of clouds: underestimation of clouds in the stratocumulus regime by most models with the corresponding consequences in terms of shortwave radiation biases; overestimation of clouds by the 40-yrECMWFRe-Analysis (ERA-40) in the deep tropics (in particular) with the corresponding impact in the outgoing longwave radiation; large spread between the different models in terms of cloud cover, liquid water path and shortwave radiation; significant differences between the models in terms of vertical cross sections of cloud properties (in particular), vertical velocity, and relative humidity. An alternative analysis of cloud cover mean statistics is proposed where sharp gradients in cloud cover along the GPCI transect are taken into account. This analysis shows that the negative cloud bias of some models and ERA-40 in the stratocumulus regions [as compared to the first International Satellite Cloud Climatology Project (ISCCP)] is associated not only with lower values of cloud cover in these regimes, but also with a stratocumulus-to-cumulus transition that occurs too early along the trade wind Lagrangian trajectory. Histograms of cloud cover along the cross section differ significantly between models. Some models exhibit a quasi-bimodal structure with cloud cover being either very large (close to 100%) or very small, while other models show a more continuous transition. The ISCCP observations suggest that reality is in-between these two extreme examples. These different patterns reflect the diverse nature of the cloud, boundary layer, and convection parameterizations in the participating weather and climate prediction models. © 2011 American Meteorological Society

Holmium laser lithotripsy for ureteral calculi: Predictive factors for complications and success

Purpose: To define possible predictive factors for success and complications for ureteroscopic holmium laser lithotripsy procedures. Patients and Methods: All 105 ureteroscopic holmium laser lithotripsy procedures performed between 1996 and 2005 were analyzed. Data recorded were sex, age, stone size, stone location, complications, success rate (stone-free rate after 3 months), operative time, and surgeon experience for this procedure. For further analysis, surgeon experience was divided into four groups based on the number of procedures performed. Multivariate analysis was used to define possible predictive factors for complications and successful procedures. Results: Total success rate was 84.8%. Complications were present in 13 patients (12.4%). Success rate was significantly (P = 0.03) related to surgeon experience, with 92.9% success in the most experienced group and 50% in the least experienced group. Furthermore, significantly more complications occurred with decreased experience (P = 0.03) complication rate was 4.2% in the highest experience group and 41.7% in the least experienced group. In our series, sex, stone location, size, and age did not significantly influence complication and success rates. Conclusion: Surgeon experience is a predictive factor for complications and success for ureteroscopic holmium laser lithotripsy for ureteric calculi. Experienced surgeons have fewer complications, and the success rate is higher. Sex, stone location, size, and age were not significantly related to complication or success rates