Preventie en bestrijding van slakken

Veel biologische telers proberen grondbewerking tegenwoordig tot een minimum te beperken. Dit is goed voor de bodemstructuur en het bodemleven. Maar minimale grondbewerking lijkt schade door slakken juist te bevorderen. Ook de brede inzet van groenbemesters kan de slakkenpopulatie bevorderen. Dit kan leiden tot aanzienlijke schade als gevolg van verontreiniging en vraat. In dit biokennisbericht een aantal handreikingen om opbrengstderving door slakken te beperken

Technological requirements for solutions in the conservation and protection of historic monuments and archaeological remains

Executive summary: This Study has discovered many achievements associated with European support for scientific and technological research for the protection and conservation of cultural heritage. The achievements to date are: 1. Creation of an active research community 2. A body of research of unparalleled and enviable international quality and character 3. Ongoing effectiveness of research beyond initial funding 4. Substantial rate of publication 5. Imaginative tools of dissemination and publication 6. Clear spin-offs and contribution to European competitiveness often going outside the European cultural heritage area 7. Contribution to emerging European legislation, for example, air quality management. The Study has also uncovered important research gaps associated with this field that have yet to begin to be investigated. It has also discovered the need for continuing fine scale advancement in areas where researchers have been active for a number of years. The overall picture is that European research in the field of cultural heritage protection must be put on a secure footing if it is to maintain its commanding lead over other regions of the world. This Study concludes that: 1. It would be invidious to attempt to separate basic and applied research in this area of research. Like any other scientific endeavour, this field needs to integrate basic and applied research if it is to continue to thrive. 2. Small, flexible, focused interdisciplinary teams responsive to European needs, must be sustained, promoted and celebrated as models of sustainability and that what is proposed under the European Research Area (ERA) for large and complex research projects, could inflict serious damage on this area of research. 3. Resources cannot be delegated to Member States because of the interdisciplinary nature of cultural heritage and the need for a co-ordinated pan-European perspective across this research that helps to define the essential character of European cultural heritage. National programmes only serve local needs, leading to loss of strategic output, lessening of competitiveness and risk of duplication. 4. A mechanism needs to be created to help researchers working in this field to communicate and exchange information with related sectors such as construction, urban regeneration, land reclamation and agriculture. 5. There is overwhelming agreement over the need for sustainable research funding for cultural heritage and for an iterative process of exchange among researchers, decision-makers and end-users in order to maximize benefits from project inception through to dissemination, audit and review. For all the reasons mentioned above, the most significant recommendation in this Report is the identification of the need for a European Panel on the Application of Science for Cultural Heritage (EPASCH)

Large-eddy simulation of a mildly curved open-channel flow

After validation with experimental data, large-eddy simulation (LES) is used to study in detail the open-channel flow through a curved flume. Based on the LES results, the present paper addresses four issues. Firstly, features of the complex bicellular pattern of the secondary flow, occurring in curved open-channel flows, and its origin are investigated. Secondly, the turbulence characteristics of the flow are studied in detail, incorporating the anisotropy of the turbulence stresses, as well as the distribution of the kinetic energy and the turbulent kinetic energy. Moreover, the implications of the pattern of the production of turbulent kinetic energy is discussed within this context. Thirdly, the distribution of the wall shear stresses at the bottom and sidewalls is computed. Fourthly, the effects of changes in the subgrid-scale model and the boundary conditions are investigated. It turns out that the counter-rotating secondary flow cell near the outer bank is a result of the complex interaction between the spatial distribution of turbulence stresses and centrifugal effects. Moreover, it is found that this outer bank cell forms a region of a local increase of turbulent kinetic energy and of its production. Furthermore, it is shown that the bed shear stresses are amplified in the bend. The distribution of the wall shear stresses is deformed throughout the bend due to curvature. Finally, it is shown that changes in the subgrid-scale model, as well as changes in the boundary conditions, have no strong effect on the result

Diferencias en las propiedades reológicas de suspensiones de cal calcítica y dolomítica: influencia de las características de las partículas e implicaciones prácticas en la fabricación de morteros de cal

The study of the rheological properties of lime suspensions is a useful means to evaluate the workability of lime mortars. In this work, we studied the flow behaviour of two industrial hydrated limes, one of calcitic and the other of dolomitic composition, by means of two types of rheometer with different geometry and setup mode. The obtained results were interpreted taking into account the differences in microstructure and surface properties of the suspended particles. Calcitic lime dry particles are formed by angular and polydisperse clusters and, once dispersed in water, they behave like thixotropic materials. On the other hand, the dolomitic lime is formed by nanoparticles and small round cluster and it shows a pronounced plastic behaviour in suspension. This fundamental difference between the two materials explains the traditional preference for dolomitic lime mortars for plastering and rendering applications.El estudio de las propiedades reológicas de suspensiones de cal es una herramienta muy útil para evaluar la trabajabilidad de morteros de cal. En este trabajo se ha estudiado el comportamiento en suspensión de dos cales hidratadas, de composición calcítica y dolomítica, mediante dos tipos de reómetros con geometría y modalidades distintas de medida. Los resultados obtenidos se han interpretado teniendo en cuenta las diferencias en la microestructura y las propiedades de superficie de las partículas en suspensión. Las partículas de cal calcítica están formadas por aglomerados angulares y polidispersos y, una vez dispersadas en agua, presentan un comportamiento tixotrópico. Por su parte, la cal dolomítica está formada por nanopartículas y pequeños agregados redondeados y muestra en suspensión un pronunciado comportamiento plástico. Esta importante diferencia entre las dos cales explica la preferencia tradicional de morteros de cal dolomítica para aplicaciones en revocos

Comparative analysis of inspection and diagnosis tools for ancient buildings

The survey and inspection of the state of conservation of buildings is understood as an active process of selecting information to support decision making in the rehabilitation of the built heritage. The development of new technologies applied to the integrated management of the built heritage resulted in digital tools able to support the technicians in on-site procedures. The purpose of this study was to analyse existing methods for the survey and inspection of the state of conservation of ancient buildings. It uses a qualitative methodology, focused on bibliographical survey and comparative analysis. Only methods with identical characteristics were considered: evaluation based on visual inspection of buildings with heritage value. This research shows that structuring information in computer systems is a solution to overcome the main problems pointed out in previous studies related to survey and inspection: expensive, time-consuming, inconsequential procedures and dispersed information. However, this is only valid if computer-based methods are adapted to the different geographic and chronological contexts. Future research may contribute to the development of a method that brings together this added value with a simple but objective way to diagnose the condition of ancient buildings with heritage value.The authors would like to acknowledge the support granted by the Portuguese Foundation for Science and Technology (FCT), in the scope of the Doctoral Program Eco-Construction and Rehabilitation (EcoCoRe), to the Ph.D. scholarship with the reference PD/BD/127853/2016 that was fundamental for the development of this study.info:eu-repo/semantics/publishedVersio

Participatory policy analysis in health policy and systems research: reflections from a study in Nepal.

Background Participatory policy analysis (PPA) as a method in health policy and system research remains underexplored. Using our experiences of conducting PPA workshops in Nepal to explore the impact of the country’s move to federalism on its health system, we reflect on the method’s strengths and challenges. We provide an account of the study context, the design and implementation of the workshops, and our reflections on the approach’s strengths and challenges. Findings on the impact of federalism on the health system are beyond the scope of this manuscript. Main body We conducted PPA workshops with a wide range of health system stakeholders (political, administrative and service-level workforce) at the local and provincial levels in Nepal. The workshops consisted of three activities: river of life, brainstorming and prioritization, and problem-tree analysis. Our experiences show that PPA workshops can be a valuable approach to explore health policy and system issues – especially in a context of widespread systemic change which impacts all stakeholders within the health system. Effective engagement of stakeholders and activities that encourage both individual- and system-level reflections and discussions not only help in generating rich qualitative data, but can also address gaps in participants’ understanding of practical, technical and political aspects of the health system, aid policy dissemination of research findings, and assist in identifying short- and long-term practice and policy issues that need to be addressed for better health system performance and outcomes. Conducting PPA workshops is, however, challenging for a number of reasons, including the influence of gatekeepers and power dynamics between stakeholders/participants. The role and skills of researchers/facilitators in navigating such challenges are vital for success. Although the long-term impact of such workshops needs further research, our study shows the usefulness of PPA workshops for researchers, for participants and for the wider health system. Conclusions PPA workshops can effectively generate and synthesize health policy and system evidence through collaborative engagement of health system stakeholders with varied roles. When designed with careful consideration for context and stakeholders’ needs, it has great potential as a method in health policy and systems research

The impacts of decentralisation on health systems: a systematic review of reviews

Background: Despite decentralisation being a common mechanism through which health systems around the world have been reformed, a clear understanding of how decentralisation impacts health systems is lacking. Although both primary and secondary research exists, the evidence remains scattered. This review collected and synthesised evidence generated by previous reviews on the impact of decentralising health system governance on the six WHO (World Health Organization) health system building blocks. Methods: We systematically searched for reviews exploring the impact of decentralisation on the health system from five databases. Reviews, both systematic and non-systematic, published in the English language from 1990 to February 2022 were included. Quality assessment of the reviews was conducted using CASP for systematic reviews and SANRA for non-systematic reviews. Results: Nine reviews, each addressing slightly different questions, contexts and health system issues, were synthesised. They showed that devolution can have positive or negative impacts on the health system and its components. Moreover, impact assessments are significantly affected by complexities surrounding decentralisation and health system concepts: their dynamic mechanisms, inconsistent and often differently operationalized health system and health system component variables, and methodological challenges. For the WHO health system components, more negative than positive impacts were reported. The reviews highlight the importance of closely assessing (pre-)existing (political and non-political) characteristics of countries and their health systems to better understand impacts. Conclusions: Decentralisation can have a negative or a positive impact on the health system and its components; the impacts are shaped by pre-existing country contexts. Generating conclusive and generalisable evidence of the impacts of decentralisation on health systems is challenging. Whilst decentralisation may seek to enhance community engagement and improve the responsiveness of decision-making, it has the potential to create serious challenges to the health system, the manifestations of which are likely to be context-specific. Protocol Registration: PROSPERO CRD4202230201

The makewaves tsunami tests and their relevance to tsunami engineering and risk management

MAKEWAVES is an international multi-partner collaborative project bringing together nine academic institutions and two commercial consultancies. The objective of the collaboration is to develop experimental data and associated numerical modelling on tsunami inundation and interaction with boulders, buildings, natural and engineered barriers, towards the development of new internationally accepted guidance for structural codes and standards. Using a pneumatic tsunami simulator (TS) developed jointly by HR Wallingford and UCL the team conducted experiments between November 2022 and April 2023 within a highly instrumented 100m long flume. The TS is capable of simulating realistic trough and crest-led tsunami waves at 1:50, including traces from the The TS is capable of generating very long trough and crest-led waves, and can reproduce at 1:50 scale waves from real life events such as the Mercator trace from the 2004 Indian Ocean event and the and 2011 Tohoku tsunamis. The TS capability has been further extended to include bore-waves. The characteristics of the waves are controlled by adjusting the flow rate and total volume of water drawn in and discharged by the TS. The experimental campaign is was subdivided into discrete research areas, each aimed at furthering knowledge on how different tsunami wave characteristics affect their interaction with manmade and natural structures environments. These include tests aimed at understanding: (1) how roughness representative of coastal forests and mangroves affects tsunami inundation characteristics, (2) how tsunami interact with boulders (3) the effectiveness of offshore breakwaters as tsunami barriers (4) how structural loads and foundation scour are affected by building permeability. This paper presents an overview of the tests conducted and some of the important early observations made that are relevant to future engineering standards and to tsunami disaster management