922 resultados para the Netherlands


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With an increased emphasis on outsourcing and shortening business cycles, contracts between firms have become more important. Carefully written contracts contribute to the efficiency and longevity of inter-firm relationships as they may constrain opportunism and are often a less costly governance mechanism than maintaining complex social relationships (Larson 1992). This exploratory examination adds to our understanding of how incomplete contracts affect interorganizational exchange. First, we consider the multiple dimensions of contract constraints (safeguards). We also investigate the extent that constraints affect decisions to enforce the relationship by delaying payments, and whether the decision is efficient. Finally, we examine the extent the constraints are effective (and ineffective) at reducing transaction problems associated with enforcement. Based on 971 observations of transactions using explicit, written terms and other secondary data in the context of IT transaction in The Netherlands we test our research propositions.

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An ongoing strong debate within the marketing discipline concerns the role of marketing within the firm. It has been frequently reported that the marketing function is in a deep decline. Marketing executives and academics alike are interested in the antecedents of this decline and potential performance consequences of this decline. Recent academic research have started investigations on this important topic. Using studies in single countries innovativeness and accountability of the marketing department has been reported as major antecedents of the influence of the marketing department within the organization. Academic research, however, does not provide convincing evidence for a direct link between this influence and business performance. Instead it shows that market orientation is a crucial intervening variable, as marketing department influence is positively related market orientation, which subsequently positively related to business performance. As noted prior research, however, studies firms in single countries. In this article we execute a cross-national study on the antecedents and performance consequences of marketing department influence in order to derive initial empirical generalizations. This study is executed in seven Western-oriented countries, including USA, UK, The Netherlands, Germany, Sweden, Israel and Australia. The study heavily builds on the framework developed in the 2009 Journal of Marketing article of Verhoef and Leeflang. This framework is tested per country and subsequently meta-analytic tests are used to derive initial empirical generalizations. An important empirical generalization is that innovativeness, the customer-connecting capabilities, and accountability of the marketing department are positively related to marketing department influence. Interestingly, a second initial generalization is that creativity of the marketing negative induces less influence. Our results also show a third empirical generalization in that firms having a CEO with a marketing background tend to have more influential marketing departments. Confirming prior research a fourth initial empirical generalization is that MD influence measures and market orientation are positively related. Market orientation is subsequently positively related to business performance. Our most important generalization is, however, that MD influence is positively related to business performance. Hence, beyond striving to become market oriented, firms should also aim to have strong marketing departments. These departments can create a stronger focus on the customer and can also coordinate marketing efforts. In order to become more influential marketing departments should: (1) acquire innovative capabilities, (2) be more connected to customers, (3) invest in accountability, and (4) be careful with be careful being too creative.

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What influence do marketing departments have in companies today? Which factors determine this influence? These are the issues discussed in the present article. Empirical evidence based on data from companies in the Netherlands demonstrates that accountability, innovativeness and customer connections are the three major drivers of influence. The need for a strong marketing department within companies is also discussed, supported by empirical data.

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Successful innovation of prescription drugs requires a substantial amount of marketing support. There is, however, much concern about the effects of marketing expenditures on the demand of pharmaceutical products (Manchanda et al., Market Lett 16(3/4):293–308, 2005). For example, excessive marketing could stimulate demand for products in the absence of a fundamental need. It also has been suggested that increased marketing expenditures may reduce the price elasticity of demand and allow firms to charge higher prices (Windmeijer et al., Health Econ 15(1):5–18, 2005). In this paper, we present the outcomes of an empirical study in which we determine the effects of pharmaceutical marketing expenditures using a number of frequently used “standardized” models. We determine which models perform best in terms of predictive validity and adequate descriptions of reality. We demonstrate, among others, that the effects of promotional efforts are brand specific and that most standardized models do not provide adequate descriptions of reality. We find that marketing expenditures have no or moderate effects on demand for pharmaceutical products in The Netherlands.

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Both marketing academics and practitioners are debating the diminished role of marketing as a separate function within firms. In this study, which expands on previous research on Dutch companies, the authors focus on how the marketing department’s capabilities relate to business performance across countries. The authors collected data in seven Western countries—the Netherlands, Germany, Sweden, United Kingdom, United States, Australia, and Israel. They surveyed top marketing and financial executives, CEOs, and other top employees of profit-based middle-sized and large firms. Their findings show that accountability provides the most consistent predictor of influence, whereas the marketing department’s innovativeness and customer connection show less consistent results. Across the seven countries, the department’s integration with the finance department has a consistent but negative effect on the department’s perceived influence. The influences of marketing departments clearly differ across countries. Perceived influence is substantially higher in the United States and Israel than in other countries, whereas top management respect for the marketing department is substantially higher in Israel than in any other country. The study also found that the marketing department is well represented on the boards of companies in Sweden, Israel, and the United States. In most countries, marketing tends not to be organized as a line function. Some differences among countries emerge in the relationships between the marketing department’s influence and business performance. In Israel, the United States, the United Kingdom, Germany, and Australia, influence relates positively to business performance, whereas in the Netherlands, it has no influence. The results for Sweden suggest a negative influence. The authors conclude that a strong marketing department appears to benefit firms in most of the countries studied. The results imply that the marketing department should have input into boardroom considerations.

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The main purpose of this dissertation is to assess the relation between municipal benchmarking and organisational learning with a specific emphasis on benchlearning and performance within municipalities and between groups of municipalities in the building and housing sector in the Netherlands. The first and main conclusion is that this relation exists, but that the relative success of different approaches to dimensions of change and organisational learning are a key explanatory factor for differences in the success of benchlearning. Seven other important conclusions could be derived from the empirical research. First, a combination of interpretative approaches at the group level with a mixture of hierarchical and network strategies, positively influences benchlearning. Second, interaction among professionals at the inter-organisational level strengthens benchlearning. Third, stimulating supporting factors can be seen as a more important strategy to strengthen benchlearning than pulling down barriers. Fourth, in order to facilitate benchlearning, intrinsic motivation and communication skills matter, and are supported by a high level of cooperation (i.e., team work), a flat organisational structure and interactions between individuals. Fifth, benchlearning is facilitated by a strategy that is based on a balanced use of episodic (emergent) and systemic (deliberate) forms of power. Sixth, high levels of benchlearning will be facilitated by an analyser or prospector strategic stance. Prospectors and analysers reach a different learning outcome than defenders and reactors. Whereas analysers and prospectors are willing to change policies when it is perceived as necessary, the strategic stances of defenders and reactors result in narrow process improvements (i.e., single-loop learning). Seventh, performance improvement is influenced by functional perceptions towards performance, and these perceptions ultimately influence the elements adopted. This research shows that efforts aimed at benchlearning and ultimately improved service delivery, should be directed to a multi-level and multi-dimensional approach addressing the context, content and process of dimensions of change and organisational learning.

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Guest editorial Ali Emrouznejad is a Senior Lecturer at the Aston Business School in Birmingham, UK. His areas of research interest include performance measurement and management, efficiency and productivity analysis as well as data mining. He has published widely in various international journals. He is an Associate Editor of IMA Journal of Management Mathematics and Guest Editor to several special issues of journals including Journal of Operational Research Society, Annals of Operations Research, Journal of Medical Systems, and International Journal of Energy Management Sector. He is in the editorial board of several international journals and co-founder of Performance Improvement Management Software. William Ho is a Senior Lecturer at the Aston University Business School. Before joining Aston in 2005, he had worked as a Research Associate in the Department of Industrial and Systems Engineering at the Hong Kong Polytechnic University. His research interests include supply chain management, production and operations management, and operations research. He has published extensively in various international journals like Computers & Operations Research, Engineering Applications of Artificial Intelligence, European Journal of Operational Research, Expert Systems with Applications, International Journal of Production Economics, International Journal of Production Research, Supply Chain Management: An International Journal, and so on. His first authored book was published in 2006. He is an Editorial Board member of the International Journal of Advanced Manufacturing Technology and an Associate Editor of the OR Insight Journal. Currently, he is a Scholar of the Advanced Institute of Management Research. Uses of frontier efficiency methodologies and multi-criteria decision making for performance measurement in the energy sector This special issue aims to focus on holistic, applied research on performance measurement in energy sector management and for publication of relevant applied research to bridge the gap between industry and academia. After a rigorous refereeing process, seven papers were included in this special issue. The volume opens with five data envelopment analysis (DEA)-based papers. Wu et al. apply the DEA-based Malmquist index to evaluate the changes in relative efficiency and the total factor productivity of coal-fired electricity generation of 30 Chinese administrative regions from 1999 to 2007. Factors considered in the model include fuel consumption, labor, capital, sulphur dioxide emissions, and electricity generated. The authors reveal that the east provinces were relatively and technically more efficient, whereas the west provinces had the highest growth rate in the period studied. Ioannis E. Tsolas applies the DEA approach to assess the performance of Greek fossil fuel-fired power stations taking undesirable outputs into consideration, such as carbon dioxide and sulphur dioxide emissions. In addition, the bootstrapping approach is deployed to address the uncertainty surrounding DEA point estimates, and provide bias-corrected estimations and confidence intervals for the point estimates. The author revealed from the sample that the non-lignite-fired stations are on an average more efficient than the lignite-fired stations. Maethee Mekaroonreung and Andrew L. Johnson compare the relative performance of three DEA-based measures, which estimate production frontiers and evaluate the relative efficiency of 113 US petroleum refineries while considering undesirable outputs. Three inputs (capital, energy consumption, and crude oil consumption), two desirable outputs (gasoline and distillate generation), and an undesirable output (toxic release) are considered in the DEA models. The authors discover that refineries in the Rocky Mountain region performed the best, and about 60 percent of oil refineries in the sample could improve their efficiencies further. H. Omrani, A. Azadeh, S. F. Ghaderi, and S. Abdollahzadeh presented an integrated approach, combining DEA, corrected ordinary least squares (COLS), and principal component analysis (PCA) methods, to calculate the relative efficiency scores of 26 Iranian electricity distribution units from 2003 to 2006. Specifically, both DEA and COLS are used to check three internal consistency conditions, whereas PCA is used to verify and validate the final ranking results of either DEA (consistency) or DEA-COLS (non-consistency). Three inputs (network length, transformer capacity, and number of employees) and two outputs (number of customers and total electricity sales) are considered in the model. Virendra Ajodhia applied three DEA-based models to evaluate the relative performance of 20 electricity distribution firms from the UK and the Netherlands. The first model is a traditional DEA model for analyzing cost-only efficiency. The second model includes (inverse) quality by modelling total customer minutes lost as an input data. The third model is based on the idea of using total social costs, including the firm’s private costs and the interruption costs incurred by consumers, as an input. Both energy-delivered and number of consumers are treated as the outputs in the models. After five DEA papers, Stelios Grafakos, Alexandros Flamos, Vlasis Oikonomou, and D. Zevgolis presented a multiple criteria analysis weighting approach to evaluate the energy and climate policy. The proposed approach is akin to the analytic hierarchy process, which consists of pairwise comparisons, consistency verification, and criteria prioritization. In the approach, stakeholders and experts in the energy policy field are incorporated in the evaluation process by providing an interactive mean with verbal, numerical, and visual representation of their preferences. A total of 14 evaluation criteria were considered and classified into four objectives, such as climate change mitigation, energy effectiveness, socioeconomic, and competitiveness and technology. Finally, Borge Hess applied the stochastic frontier analysis approach to analyze the impact of various business strategies, including acquisition, holding structures, and joint ventures, on a firm’s efficiency within a sample of 47 natural gas transmission pipelines in the USA from 1996 to 2005. The author finds that there were no significant changes in the firm’s efficiency by an acquisition, and there is a weak evidence for efficiency improvements caused by the new shareholder. Besides, the author discovers that parent companies appear not to influence a subsidiary’s efficiency positively. In addition, the analysis shows a negative impact of a joint venture on technical efficiency of the pipeline company. To conclude, we are grateful to all the authors for their contribution, and all the reviewers for their constructive comments, which made this special issue possible. We hope that this issue would contribute significantly to performance improvement of the energy sector.

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For 35 years, Arnstein's ladder of citizen participation has been a touchstone for policy makers and practitioners promoting user involvement. This article critically assesses Arnstein's writing in relation to user involvement in health drawing on evidence from the United Kingdom, the Netherlands, Finland, Sweden and Canada. Arnstein's model, however, by solely emphasizing power, limits effective responses to the challenge of involving users in services and undermines the potential of the user involvement process. Such an emphasis on power assumes that it has a common basis for users, providers and policymakers and ignores the existence of different relevant forms of knowledge and expertise. It also fails to recognise that for some users, participation itself may be a goal. We propose a new model to replace the static image of a ladder and argue that for user involvement to improve health services it must acknowledge the value of the process and the diversity of knowledge and experience of both health professionals and lay people.

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As we welcome 2014 we say goodbye to 2013 and I must start with an apology to authors who have submitted papers to CLAE and seen a delay in either the review process or the hard copy publication of their proofed article. The delays were caused by a major hike in the number of submissions to the journal in 2012 that increased further in 2013. In the 12 months leading to the end of October 2011 we had 94 new paper submissions, and for the same period to the end of 2012 the journal had 116 new papers. In 2012 we were awarded an impact factor for the first time and following that the next 12 month period to the end of October 2013 saw a massive increase in submissions with 171 new manuscripts being submitted. This is nearly twice as many papers as 2 years ago and 3 times as many as when I took over as Editor-in-Chief. In addition to this the UK academics will know that 2014 is a REF year (Research Excellence Framework) where universities are judged on their research and one of the major components of this measure remains to be published papers so there is a push to publishing before the REF deadline for counting. The rejection rate at CLAE has gone up too and currently is around 50% (more than double the rejection rate when I took over as Editor-in-Chief). At CLAE the number of pages that we publish each year has remained the same since 2007. When compiling issue 1 for 2014 I chose the papers to be included from the papers that were proofed and ready to go and there were around 200 proofed pages ready, which is enough to fill 3½ issues! At present Elsevier and the BCLA are preparing to increase the number the pages published per issue so that we can clear some of this backlog and remain up to date with the papers published in CLAE. I should add that on line publishing of papers is still available and there may have been review delays but there are no publishing online so authors can still get an epub on line final version of their paper with a DOI (digital object identifier) number enabling the paper to be cited. There are two awards that were made in 2013 that I would like to make special mention of. One was for my good friend Jan Bergmanson, who was awarded an honorary life fellowship of the College of Optometrists. Jan has served on the editorial board of CLAE for many years and in 2013 also celebrated 30 years of his annual ‘Texan Corneal and contact lens meeting’. The other award I wish to mention is Judith Morris, who was the BCLA Gold Medal Award winner in 2013. Judith has had many roles in her career and worked at Moorfields Eye Hospital, the Institute of Optometry and currently at City University. She has been the Europe Middle East and Africa President of IACLE (International Association of Contact Lens Educators) for many years and I think I am correct in saying that Judith is the only person who was President of both the BCLA (1983) and a few years later she was the President College of Optometrists (1989). Judith was also instrumental in introducing Vivien Freeman to the BCLA as they had been friends and Judith suggested that Vivien apply for an administrative job at the BCLA. Fast forward 29 years and in December 2013 Vivien stepped down as Secretary General of the BCLA. I would like to offer my own personal thanks to Vivien for her support of CLAE and of me over the years. The BCLA will not be the same and I wish you well in your future plans. But 2014 brings in a new position to the BCLA – Cheryl Donnelly has been given the new role of Chief Executive Officer. Cheryl was President of the BCLA in 2000 and has previously served on council. I look forward to working with Cheryl and envisage a bright future for the BCLA and CLAE. In this issue we have some great papers including some from authors who have not published with CLAE before. There is a nice paper on contact lens compliance in Nepal which brings home some familiar messages from an emerging market. A paper on how corneal curvature is affected by the use of hydrogel lenses is useful when advising patients how long they should leave their contact lenses out for to avoid seeing changes in refraction or curvature. This is useful information when refracting these patients or pre-laser surgery. There is a useful paper offering tips on fitting bitoric gas permeable lenses post corneal graft and a paper detailing surgery to implant piggyback multifocal intraocular lenses. One fact that I noted from the selection of papers in the current issue is where they were from. In this issue none of the corresponding authors are from the United Kingdom. There are two papers each from the United States, Spain and Iran, and one each from the Netherlands, Ireland, Republic of Korea, Australia and Hong Kong. This is an obvious reflection of the widening interest in CLAE and the BCLA and indicates the new research groups emerging in the field.

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Full text: It seems a long time ago now since we were at the BCLA conference. The excellent FIFA World Cup in Brazil kept us occupied over the summer as well as Formula 1, Wimbledon, Tour de France, Commonwealth Games and of course exam paper marking! The BCLA conference this year was held in Birmingham at the International Convention Centre which again proved to be a great venue. The number of attendees overall was up on previous years, and at a record high of 1500 people. Amongst the highlights at this year's annual conference was the live surgery link where Professor Sunil Shah demonstrated the differences in technique between traditional phacoemulsification cataract surgery and femtosecond assisted phacoemulsification cataract surgery. Dr. Raquel Gil Cazorla, a research optometrist at Aston University, assisted in the procedure including calibrating the femtosecond laser. Another highlight for me was the session that I chaired, which was the international session organised by IACLE (International Association of CL Educators). There was a talk by Mirjam van Tilborg about dry eye prevalence in the Netherlands and how it was managed by medical general practitioners (GPs) or optometrists. It was interesting to know that there are only 2 schools of optometry there and currently under 1000 registered optometrists there. It also seems that GPs were more likely to blame CL as the cause for dry eye whereas optometrists who had a fuller range of tests were better at solving the issue. The next part of the session included the presentation of 5 selected posters from around the world. The posters were also displayed in the main poster area but were selected to be presented here as they had international relevance. The posters were: 1. Motivators and Barriers for Contact Lens Recommendation and Wear by Nilesh Thite (India) 2. Contact lens hygiene among Saudi wearers by Dr. Ali Masmaly (Saudi) 3. Trends of contact lens prescribing and patterns of contact lens practice in Jordan by Dr. Mera Haddad (Jordan) 4. Contact Lens Behaviour in Greece by Dr. Dimitra Makrynioti (Greece) 5. How practitioners inform ametropes about the benefits of contact lenses and overcome the potential barriers: an Italian survey, by Dr. Fabrizio Zeri (Italy) It was interesting to learn about CL practice in different parts, for example the CL wearing population ration in Saudi Arabia is around 1:2 Male:Female (similar to other parts of the world) and although the sale of CL is restricted to registered practitioners there are many unregistered outlets, like clothing stores, that flout the rules. In Jordan some older practitioners will still advise patients to use tap water or even saliva! But thankfully the newer generation of practitioners have been educated not to advise this. In Greece one of the concerns was that some practitioners may advise patients to use disposable lenses for longer than they should and again it seems to be the practitioners with inadequate education that would do this. In India it was found that cost was one barrier to using contact lenses but also some practitioners felt that they shouldn’t offer CLs due to cost too. In Italy sensitive eyes and CL care and maintenance were the barriers to CL wear but the motivators were vision and comfort and aesthetics. Finally the international session ended with the IACLE travel award and educator awards presented by IACLE president Shehzad Naroo and BCLA President Andrew Yorke. The travel award went to Wang Ling, Jinling Institute of Technology, Nanjing, China. There were 3 regional Contact Lens Educator of the Year Awards sponsored by Coopervision and presented by Dr. J.C. Aragorn of Coopervision. 1. Asia Pacific Region – Dr. Rajeswari Mahadevan of Sankara Nethralaya Medical Research Foundation, Chennai, India 2. Americas Region – Dr. Sergio Garcia of University of La Salle, Bogotá and the University Santo Tomás, Bucaramanga, Colombia 3. Europe/Africa – Middle East Region: Dr. Eef van der Worp, affiliated with the University of Maastricht, the Netherlands The posters above were just a small selection of those displayed at this year's BCLA conference. If you missed the BCLA conference then you can see the abstracts for all posters and talks in a virtual issue of CLAE very soon. The poster competition was kindly sponsored by Elsevier. The poster winner this year was: Joan Gispets – Corneal and Anterior Chamber Parameters in Keratoconus The 3 runners up were: Debby Yeung – Scleral Lens Central Corneal Clearance Assessment with Biomicroscopy Sarah L. Smith – Subjective Grading of Lid Margin Staining Heiko Pult – Impact of Soft Contact Lenses on Lid Parallel Conjunctival Folds My final two highlights are a little more personal. Firstly, I was awarded Honorary Life Fellowship of the BCLA for my work with the Journal, and I would like to thank the BCLA, Elsevier, the editorial board of CLAE, the reviewers and the authors for their support of my role. My final highlight from the BCLA conference this year was the final presentation of the conference – the BCLA Gold Medal award. The recipient this year was Professor Philip Morgan with his talk ‘Changing the world with contact lenses’. Phil was the person who advised me to go to my first BCLA conference in 1994 (funnily he didn’t attend himself as he was busy getting married!) and now 20 years later he was being honoured with the accolade of being the BCLA Gold Medallist. The date of his BCLA medal addressed was shared with his father's birthday so a double celebration for Phil. Well done to outgoing BCLA President Andy Yorke and his team at the BCLA (including Nick Rumney, Cheryl Donnelly, Sarah Greenwood and Amir Khan) on an excellent conference. And finally welcome to new President Susan Bowers. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

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The article addresses the bias in interest representation within the EU by examining the lobbying strategies of national interest organisations within the EU’s multilevel political system. Both our theoretical framework, which includes the determinants of a national interest organisation's decision to act at the EU level, and the data analysis from the INTEREURO Multi-Level Governance Module (MLG) (www.intereuro.eu) reveal three main findings. Firstly, the greatest differentiation among interest organisations (IOs) appears to be between those IOs from the older member states (Germany, the UK and the Netherlands), which exhibit above-average levels of activity, and those from the newer EU member states (Sweden, Slovenia), which exhibit below-average levels of activity. Secondly, the variations in IO activity levels are much greater from country to country than from one policy field to another. Thirdly, although the IOs from all five countries in our study are more likely to employ media and publishing strategies (information politics) than to mobilise their members and supporters (protest politics), we can still observe national patterns in their selection of strategies and in the intensity of their instrumentalisation.

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Technology: Infliximab and comparator biological such as adalimumab, etanercept, golimumab. Conditions: Ankylosing spondylitis (AS) Issue: Infliximab is registered to be used in patients with AS. The aim of the Report is to evaluate the clinical efficacy and safety of infliximab and comparator biologicals for the treatment of adult AS. Methods: Systematic literature review and analysis as well as meta-analysis (direct and indirect comparison) of published randomised controlled clinical trials (RCT) were performed, all relevant health economics literature were identified ad analysed. Results: Clinical efficacy of biological therapies is based on good clinical evidences regarding to all clinical efficacy endpoints (ASAS20, ASAS40, ASAS 5/6, and BASDAI 50% response). Altogether, 22 trials are included in our meta-analysis, 12 infliximab, 3 adalimumab studies, 6 etanercept and 1 golimumab. Efficacy of biological treatments for the treatment of AS has been established by clinical scientific evidences, significant improvement at all outcomes considered was confirmed. According to the results of indirect comparison, there were no significant difference between biological treatments and placebo in terms of safety and tolerability endpoints. We found no significant difference between the clinical efficacy and safety of infliximab, adalimumab, etanercept and golimumab therapies. Cost-utility analysis of adalimumab and/or infliximab, etanercept and golimumab treatment for AS were performed in the UK, Canada, The Netherlands, Germany, Spain and France. There are no cost-utility studies from Eastern Central Europe. Implications for decision making: Efficacy of infliximab and comparator biologicals for the treatment of Ankylosing Spondylitis (AS) was proved by clinical evidence, significant improvement at all outcomes considered was confirmed. We found no significant differences in efficacy and safety of different biological treatments. Health economics results suggest that biological therapies are cost-effective alternatives for the treatment of AS in group of developed high income countries. There is a lack of health economics results in Central-Eastern European countries however these data are more and more required by governments and funders as part of the company economic dossiers.

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In the framework of the global energy balance, the radiative energy exchanges between Sun, Earth and space are now accurately quantified from new satellite missions. Much less is known about the magnitude of the energy flows within the climate system and at the Earth surface, which cannot be directly measured by satellites. In addition to satellite observations, here we make extensive use of the growing number of surface observations to constrain the global energy balance not only from space, but also from the surface. We combine these observations with the latest modeling efforts performed for the 5th IPCC assessment report to infer best estimates for the global mean surface radiative components. Our analyses favor global mean downward surface solar and thermal radiation values near 185 and 342 Wm**-2, respectively, which are most compatible with surface observations. Combined with an estimated surface absorbed solar radiation and thermal emission of 161 Wm**-2 and 397 Wm**-2, respectively, this leaves 106 Wm**-2 of surface net radiation available for distribution amongst the non-radiative surface energy balance components. The climate models overestimate the downward solar and underestimate the downward thermal radiation, thereby simulating nevertheless an adequate global mean surface net radiation by error compensation. This also suggests that, globally, the simulated surface sensible and latent heat fluxes, around 20 and 85 Wm**-2 on average, state realistic values. The findings of this study are compiled into a new global energy balance diagram, which may be able to reconcile currently disputed inconsistencies between energy and water cycle estimates.

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Bedforms such as dunes and ripples are ubiquitous in rivers and coastal seas, and commonly described as triangular shapes from which height and length are calculated to estimate hydrodynamic and sediment dynamic parameters. Natural bedforms, however, present a far more complicated morphology; the difference between natural bedform shape and the often assumed triangular shape is usually neglected, and how this may affect the flow is unknown. This study investigates the shapes of natural bedforms and how they influence flow and shear stress, based on four datasets extracted from earlier studies on two rivers (the Rio Paraná in Argentina, and the Lower Rhine in The Netherlands). The most commonly occurring morphological elements are a sinusoidal stoss side made of one segment and a lee side made of two segments, a gently sloping upper lee side and a relatively steep (6 to 21°) slip face. A non-hydrostatic numerical model, set up using Delft3D, served to simulate the flow over fixed bedforms with various morphologies derived from the identified morphological elements. Both shear stress and turbulence increase with increasing slip face angle and are only marginally affected by the dimensions and positions of the upper and lower lee side. The average slip face angle determined from the bed profiles is 14°, over which there is no permanent flow separation. Shear stress and turbulence above natural bedforms are higher than above a flat bed but much lower than over the often assumed 30° lee side angle.