678 research outputs found
Filling some black holes: modeling the connection between urbanization, infrastructure, and global service intensity in 112 metropolitan regions across the world
This empirical article combines insights from previous research on the level of knowledge-intensive service in metropolitan areas with the aim to develop an understanding of the spatial structure of the global service economy. We use a stepwise regression model with GaWC’s measure of globalized service provisioning as the dependent variable and a range of variables focusing on population, infrastructure, urban primacy, and national regulation as independent variables. The discussion of the results focuses on model parameters as well as the meaning of outliers, and is used to explore some avenues for future research
Tribute to Eileen J. Cox - Editorial
This issue is dedicated to Dr. Eileen Joan Cox on the occasion of her 70th birthday. Eileen is a very well-known phycologist who has made a major contribution to diatom research, for instance in terms of scientific papers published and species described (all listed in pages 412–414 of this issue) but also in addressing different topics (e.g. taxonomy of particular groups, the ecology of streams and tube dwelling
diatoms, life-history and morphogenesis, valve terminology, the chloroplasts of living diatoms, and many others). The photos on the issue’s cover were chosen to reflect some of these aspects of Eileen’s work: Navicula oblonga refers to her work and advocacy of research on living diatoms; Encyonema refers to her earliest work on diatoms that live inside polysaccharide tubes; and Navicula refers to Eileen’s principal taxonomic focus over many years – the diatoms that used to be classified in the catch-all genus Navicula, which have now been split off and placed into many different genera. However, perhaps the most important contribution of a scientist is one that cannot be so easily measured, and that is the positive impact and influence the scientist makes on her/his colleagues. In this respect, Eileen’s contribution has been
huge: she has always facilitated collaborations, welcoming students and visitors and putting facilities at their disposal, always taking care of the person as well as the work. She has also volunteered her time and energy generously to scientific societies, editing journals and many other good causes. Not surprisingly we (editors) did not have to make any effort to convince researchers to contribute to this issue. In fact, we
faced the opposite problem in having to restrict the number of papers quite severely to keep the issue manageable. We would like to take this opportunity to apologize to all those who would have liked to contribute but have been left out.info:eu-repo/semantics/publishedVersio
Vitality club:a proof-of-principle of peer coaching for daily physical activity by older adults
Many age-related diseases can be prevented or delayed by daily physical activity. Unfortunately, many older adults do not perform physical activity at the recommended level. Professional interventions do not reach large numbers of older adults for a long period of time. We studied a peer-coach intervention, in which older adults coach each other, that increased daily physical activity of community dwelling older adults for over 6 years. We studied the format and effects of this peer coach intervention for possible future implementation elsewhere. Through interviews and participatory observation we studied the format of the intervention. We also used a questionnaire (n = 55) and collected 6-min walk test data (n = 261) from 2014 to 2016 to determine the motivations of participants and effects of the intervention on health, well-being and physical capacity. Vitality Club is a self-sustainable group of older adults that gather every weekday to exercise coached by an older adult. Members attend on average 2.5 days per week and retention rate is 77.5% after 6 years. The members perceived improvements in several health measures. In line with this, the 6-min walk test results of members of this Vitality Club improved with 21.7 meters per year, compared with the decline of 2-7 meters per year in the general population. This Vitality Club is successful in durably engaging its members in physical activity. The members perceive improvements in health that are in line with improvements in a physical function test. Because of the self-sustainable character of the intervention, peer coaching has the potential to be scaled up at low cost and increase physical activity in the increasing number of older adults
Increasing risk behaviour can outweigh the benefits of antiretroviral drug treatment on the HIV incidence among men-having-sex-with-men in Amsterdam
Background: The transmission through contacts among MSM (men who have sex with men) is one of the dominating contributors to HIV prevalence in industrialized countries. In Amsterdam, the capital of the Netherlands, the MSM risk group has been traced for decades. This has motivated studies which provide detailed information about MSM's risk behavior statistically, psychologically and sociologically. Despite the era of potent antiretroviral therapy, the incidence of HIV among MSM increases. In the long term the contradictory effects of risk behavior and effective therapy are still poorly understood.Methods: Using a previously presented Complex Agent Network model, we describe steady and casual partnerships to predict the HIV spreading among MSM. Behavior-related parameters and values, inferred from studies on Amsterdam MSM, are fed into the model; we validate the model using historical yearly incidence data. Subsequently, we study scenarios to assess the contradictory effects of risk behavior and effective therapy, by varying corresponding values of parameters. Finally, we conduct quantitative analysis based on the resulting incidence data.R
Revision of the Staurosirella leptostauron complex (Staurosiraceae, Bacillariophyta) in Europe with the description of three new species
Background and aims – Small-celled araphid diatoms form an important part of the diatom flora in our rivers and lakes. Although several of these species are frequently reported, their correct taxonomic identity is often obscured due to a lack of good knowledge of the original (type) material.
Material and methods – Several historical (nineteenth century) original samples were retrieved from different European and North American diatom collections. The samples have been analysed using light (LM) and scanning electron microscopy (SEM).
Key results – Staurosirella crux comb. nov., based on Ehrenberg’s Navicula crux, proved to be the oldest valid name for Staurosirella harrisonii, the latter now being considered a younger synonym. A new European species, S. neorhomboides sp. nov., is described to replace the name S. rhomboides, now considered a younger synonym of S. leptostauron. The North American populations of S. rhomboides and S. martyi differ sufficiently from the type populations and are described as new species: S. moralesii sp. nov. and S. manoyloviana sp. nov. The new combination Staurosirella informis comb. nov. is proposed for a taxon described in 1856 from the French Pyrenees as Odontidium informe. Staurosirella leptostauron turns out to be insufficiently described and is now documented for further use.
Conclusion – The analysis of the original (type) material corrected several taxonomic errors and better characterised the morphology of several commonly observed Staurosirella species
Filling some black holes: modeling the connection between urbanization, infrastructure, and global service intensity
This empirical article combines insights from previous research on the level of knowledge-intensive service in metropolitan areas with the aim to develop an understanding of the spatial structure of the global service economy. We use a stepwise regression model with the Globalization and World Cities research network's measure of globalized service provisioning as the dependent variable and a range of variables focusing on population, infrastructure, urban primacy, and national regulation as independent variables. The discussion of the results focuses on model parameters as well as the meaning of outliers and is used to explore some avenues for future research
Self-organizing peer coach groups to increase daily physical activity in community dwelling older adults
Many older adults do not reach the recommended level of physical activity, despite many professional-delivered physical activity interventions. Here we study the implementation of a novel physical activity intervention for older adults that is self-sustainable (no financial support) and self-organizing (participants act as organizers) due to peer coaching. We implemented three groups and evaluated process and effect using participatory observations, questionnaires, six-minute walk tests and body composition measures from October 2016 to September 2018. The intervention was implemented by staff without experience in physical activity interventions. Facilitators were a motivated initiator and a non-professional atmosphere for participants to take ownership. Barriers were the absence of motivated participants to take ownership and insufficient participants to ensure the presence of participants at every exercise session. The groups exercised outside five days a week and were self-organizing after 114, 216 and 263 days. The initial investments were 170_ for sport equipment and 81-187 h. The groups reached 118 members and a retention of 86.4% in two years. The groups continue to exist at the time of writing and are self-sustainable. Quality of life increased 0.4 on a ten-point scale (95%CI 0.1-0.7; p = 0.02) and six-minute walk test results improved with 33 m (95%CI 18-48; p < 0.01) annually. Self-organizing peer coach groups for physical activity are feasible, have positive effects on health and require only a small investment at the start. It is a sustainable and potentially scalable intervention that could be a promising method to help many older adults age healthier
Letter to the editor: Pre-exposure prophylaxis for HIV in Europe: The need for resistance surveillance
__To the editor:__ In a recent paper by Hauser et al. in this journal, a prevalence of 10.8% of transmitted drugresistant viruses was reported among newly diagnosed HIV cases in Germany in 2013 and 2014.
The authors conclude that genotypic resistance testing remains important for treatment as well as HIV prevention. We comment on the use of pre-exposure prophylaxis (PrEP) in relation to drug resistance in HIV infections and the need for European surveillance of drug resistance
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