Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Laser Speckle Strain Imaging reveals the origin of delayed fracture in a soft solid
Kooij, Hanne M. van der; Dussi, Simone ; Kerkhof, Gea T. van de; Frijns, Raoul A.M. ; Gucht, Jasper van der; Sprakel, Joris - \ 2018
Science Advances 4 (2018)5. - ISSN 2375-2548

Stresses well below the critical fracture stress can lead to highly unpredictable delayed fracture after a long period of seemingly quiescent stability. Delayed fracture is a major threat to the lifetime of materials, and its unpredictability makes it difficult to prevent. This is exacerbated by the lack of consensus on the microscopic mechanisms at its origin because unambiguous experimental proof of these mechanisms remains absent. We present an experimental approach to measure, with high spatial and temporal resolution, the local deformations that precipitate crack nucleation. We apply this method to study delayed fracture in an elastomer and find that a delocalized zone of very small strains emerges as a consequence of strongly localized damage processes. This prefracture deformation zone grows exponentially in space and time, ultimately culminating in the nucleation of a crack and failure of the material as a whole. Our results paint a microscopic picture of the elusive origins of delayed fracture and open the way to detect damage well before it manifests macroscopically.

Systematic variation of membrane casting parameters to control the structure of thermo-responsive isoporous membranes
Mocan, Merve ; Wahdat, Hares ; Kooij, Hanne M. van der; Vos, Wiebe M. de; Kamperman, Marleen - \ 2018
Journal of Membrane Science 548 (2018). - ISSN 0376-7388 - p. 502 - 509.
Block copolymer self-assembly - Fully reversible thermo-responsive nanoporous isoporous block copolymer membranes - PS-PNIPAM block copolymers - RAFT polymerization - Self-assembly and non-solvent induced phase separation (SNIPS) method
Fouling is a critical issue in membrane process operation as it greatly compromises the efficiency of the treatment processes. A promising approach to overcome this problem is the production of easy-to-clean membranes by incorporating stimuli-responsive pores. In this study, we fabricated thermo-responsive polystyrene-b-poly(N-isopropyl acrylamide) (PS-b-PNIPAM) block copolymer membranes using the self-assembly and non-solvent induced phase separation (SNIPS) method and systematically varied several membrane casting parameters, i.e. evaporation time, polymer concentration, solvent type and water content, to obtain nano- and isoporous membranes. Membranes with a disordered surface were obtained for PS selective solvents, whereas isoporous membranes were obtained when the block copolymers were dissolved in PNIPAM selective solvent mixtures. Using 1,4-dioxane/ tetrahydrofuran mixtures resulted in isoporous membranes for a large parameter space, indicating the robustness of structure formation in the PS-b-PNIPAM system. Permeability tests at various temperatures demonstrated fully reversible thermo-responsive behavior of the membranes.
Literatuurstudie waarde halen uit groenresten in het waterbeheer
Doorn, Wim van; Kooij, Aldert van der; Dam, Jan van - \ 2017
Amersfoort : Stichting Toegepast Onderzoek Waterbeheer (Stowa rapport 2017-04) - ISBN 9789057737404 - 93
reststromen - biobased economy - waterbeheer - bioraffinage - grasmaaisel - waterplanten - composieten - residual streams - water management - biorefinery - grass clippings - aquatic plants - composite materials
Dit rapport beschrijft de resultaten van de verkennende literatuurstudie naar de mogelijkheden voor verwaarding via bioraffinage van vrijkomend maaisel en in het waterbeheer af te voeren waterplanten. Daartoe is een inventarisatie gemaakt van de vrijkomende hoeveelheden en samenstelling van maaisels bij de acht deelnemende waterschappen en is via een literatuurstudie informatie verzameld over de fysisch-chemische samenstelling van de meest voorkomende planten in de maaisels. Daarbij is een literatuurscan uitgevoerd van de wetenschappelijke literatuur naar wat bekend is over biomassa samenstelling van de meest voorkomende niet-inheemse waterplanten en de aanwezigheid van specifieke inhoudstoffen voor verwaarding. Op basis van deze informatie en inzicht in biobased conversie technieken, is een inschatting gemaakt van het potentieel voor verwaarding van deze groenresten door waterschappen. Mogelijke producten zijn eiwitten voor veevoeder of technische toepassingen, vezels voor papier/karton of diverse biocomposiet-toepassingen, en soms zijn specifieke inhoudstoffen aanwezig, zoals gelerende stoffen of antioxidantia.
A user-centred approach to irrigation performance : drip irrigation in the Khrichfa area, Morocco
Kooij, Saskia van der; Kuper, Marcel ; Zwarteveen, Margreet Z. ; Fraiture, Charlotte M.S. de - \ 2017
Water International 42 (2017)7. - ISSN 0250-8060 - p. 794 - 809.
dripirrigation - Micro-irrigation - Morocco - performanceassessment
Conventional irrigation performance assessments narrowly confine the possible effects of using drip irrigation to what it is designed to do, i.e., improve efficiencies. While helpful in the design, such assessments leave little scope for the possibility that irrigators adopt the technology for reasons other than improving efficiencies. Using a case study about how irrigators in the farmer-managed Khrichfa Canal in Morocco engaged with drip irrigation, we propose a user-centred approach to irrigation performance. Use of this approach opens up the possibility that a technology is used and mobilized for other reasons than only those intended in the design process.
Re-allocating yet-to-be-saved water in irrigation modernization projects: the case of the Bittit irrigation system, Morocco
Kooij, S. van der; Kuper, M. ; Fraiture, C.M.S. de; Lankford, Bruce ; Zwarteveen, M.Z. - \ 2017
In: Drip Irrigation for Agriculture / Venot, Jean-Philippe, Marcel, Kuper, Margreet, Zwarteveen, Oxon : Earthscan/Routledge - ISBN 9781138687073 - p. 68 - 84.
Imaging the Molecular Motions of Autonomous Repair in a Self-Healing Polymer
Kooij, Hanne M. van der; Susa, Arijana ; García, Santiago J. ; Zwaag, Sybrand van der; Sprakel, Joris - \ 2017
Advanced materials 29 (2017)26. - ISSN 0935-9648
Laser speckle Imaging - Nonlinear mechanics - Polymer dynamics - Self-healing - Thermoplastic elastomers
Self-healing polymers can significantly extend the service life of materials and structures by autonomously repairing damage. Intrinsic healing holds great promise as a design strategy to mitigate the risks of damage by delaying or preventing catastrophic failure. However, experimentally resolving the microscopic mechanisms of intrinsic repair has proven highly challenging. This work demonstrates how optical micromechanical mapping enables the quantitative imaging of these molecular-scale dynamics with high spatiotemporal resolution. This approach allows disentangling delocalized viscoplastic relaxation and localized cohesion-restoring rebonding processes that occur simultaneously upon damage to a self-healing polymer. Moreover, frequency- and temperature-dependent imaging provides a way to pinpoint the repair modes in the relaxation spectrum of the quiescent material. These results give rise to a complete picture of autonomous repair that will guide the rational design of improved self-healing materials.
Mycoplasma detection by triplex real-time PCR in bronchoalveolar lavage fluid from bovine respiratory disease complex cases
Cornelissen, Jan B.W.J. ; Bree, Freddy M. de; Wal, Fimme J. van der; Kooij, Engbert A. ; Koene, Miriam G.J. ; Bossers, Alex ; Smid, Bregtje ; Antonis, Adriaan F. ; Wisselink, Henk J. - \ 2017
BMC Veterinary Research 13 (2017)1. - ISSN 1746-6148
Bovine Mycoplasma - Bovine respiratory disease - M. bovirhinis - M. bovis - M. dispar - RespoCheck - Triplex PCR

Background: In this study we evaluated the RespoCheck Mycoplasma triplex real-time PCR for the detection in bronchoalveolar lavage fluid (BALF) of Mycoplasma (M.) dispar, M. bovis and M. bovirhinis, all three associated with bovine respiratory disease (BRD). Primers and probes of the RespoCheck Mycoplasma triplex real-time PCR are based on the V3/V4 region of the 16S rRNA gene of the three Mycoplasma species. Results: The analytical sensitivity of the RespoCheck triplex real-time PCR was, as determined by spiking experiments of the Mycoplasma strains in Phosphate Buffered Saline, 300 colony forming units (cfu)/mL for M. dispar, and 30cfu/mL for M. bovis or M. bovirhinis. The analytical sensitivity of the RespoCheck Mycoplasma triplex real-time PCRwas, as determined on purified DNA, 10fg DNA per assay for M. dispar and 100fg fo rM. bovis and M. bovirhinis. The analytical specificity of the RespoCheck Mycoplasma triplex real-time PCR was, as determined by testing Mycoplasmas strains (n=17) and other bacterial strains (n=107), 100, 98.2 and 99.1% for M. bovis, M. dispar and M. bovirhinis respectively. The RespoCheck Mycoplasma triplex real-time PCR was compared with the PCR/DGGE analysis for M. bovis, M. dispar and M. bovirhinis respectively by testing 44 BALF samples from calves. Conclusion: In conclusion, the RespoCheck PCR assay can be a valuable tool for timely and accurate detection of three Mycoplasma species associated with in bovine respiratory disease.

Free-standing thermo-responsive nanoporous membranes from high molecular weight PS-PNIPAM block copolymers synthesized via RAFT polymerization
Cetintas, Merve ; Grooth, Joris De; Hofman, Anton H. ; Kooij, Hanne M. Van der; Loos, Katja ; Vos, Wiebe M. De; Kamperman, Marleen - \ 2017
Polymer Chemistry 8 (2017)14. - ISSN 1759-9954 - p. 2235 - 2243.
The incorporation of stimuli-responsive pores in nanoporous membranes is a promising approach to facilitate the cleaning process of the membranes. Here we present fully reversible thermo-responsive nanoporous membranes fabricated by self-assembly and non-solvent induced phase separation (SNIPS) of polystyrene-poly(N-isopropylacrylamide) (PS-PNIPAM) block copolymers. A variety of PS-PNIPAM block copolymers were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and the reaction conditions were optimized. The target copolymers featured: (1) a thermo-responsive PNIPAM block, (2) a majority PS fraction, and (3) a well-defined high molecular weight, which are requirements for successful fabrication of free-standing responsive membranes using SNIPS. The resulting membranes exhibited a worm-like cylindrical morphology with interconnected nanopores. The thermo-responsive character of the membranes was studied by measuring the permeability of the membranes as a function of temperature. The permeability was found to increase by almost 400% upon going from room temperature to 50 °C and this thermo-responsive character was fully reversible.
Transformations accompanying a shift from surface to drip irrigation in the Cànyoles Watershed, Valencia, Spain
Sese-Minguez, Saioa ; Boesveld, Harm ; Asins-Velis, Sabina ; Kooij, Saskia van der; Maroulis, Jerry - \ 2017
Water Alternatives 10 (2017)1. - ISSN 1965-0175 - p. 81 - 99.
Agricultural land use/expansion - Cultural heritage loss - Cànyoles watershed - Drip irrigation - Energy consumption - Spain - Water saving

Drip irrigation is widely promoted in Spain to increase agricultural production and to save water. In the Cànyoles watershed, Valencia, we analysed the consequences of change from surface irrigation to drip irrigation over the past 25 years. There were a number of transformations resulting from, or accelerated by, this change including the 1) intensification of well construction causing a redistribution in access to groundwater, water shortages and a lowering of the groundwater table; 2) expansion of irrigation into former rain-dependent uphill areas resulting in increased water use; 3) shift to higher- value monoculture fruit crops, but with associated higher crop water requirements; 4) increased electrical energy consumption and higher costs due to groundwater pumping; and 5) loss of cultural heritage as wells have replaced traditional surface irrigation infrastructure that originated in the Middle Ages. Consequently, the authors argue that transitioning from surface irrigation to drip irrigation should critically look beyond the obvious short-term benefits that are intended by the introduction of the technology, and consider possible unforeseen side effects, that may have serious long-term impacts on the environment and the community.

Quantitative imaging of heterogeneous dynamics in drying and aging paints
Kooij, Hanne M. Van Der; Fokkink, Remco ; Gucht, Jasper Van Der; Sprakel, Joris - \ 2016
Scientific Reports 6 (2016). - ISSN 2045-2322

Drying and aging paint dispersions display a wealth of complex phenomena that make their study fascinating yet challenging. To meet the growing demand for sustainable, high-quality paints, it is essential to unravel the microscopic mechanisms underlying these phenomena. Visualising the governing dynamics is, however, intrinsically difficult because the dynamics are typically heterogeneous and span a wide range of time scales. Moreover, the high turbidity of paints precludes conventional imaging techniques from reaching deep inside the paint. To address these challenges, we apply a scattering technique, Laser Speckle Imaging, as a versatile and quantitative tool to elucidate the internal dynamics, with microscopic resolution and spanning seven decades of time. We present a toolbox of data analysis and image processing methods that allows a tailored investigation of virtually any turbid dispersion, regardless of the geometry and substrate. Using these tools we watch a variety of paints dry and age with unprecedented detail.

Performing drip irrigation by the farmer managed Seguia Khrichfa irrigation system, Morocco
Kooij, S. van der - \ 2016
University. Promotor(en): Charlotte de Fraiture; Margreet Zwarteveen, co-promotor(en): M. Kuper. - Wageningen : Wageningen University - ISBN 9789462577626 - 166 p.
trickle irrigation - irrigation systems - efficiency - morocco - druppelbevloeiing - irrigatiesystemen - efficiëntie - marokko

Drip irrigation is represented in literature and agricultural policies as a modern and water saving technology. Because this technology is often associated with ‘modern’ agriculture and development, it seems out-of-place in ‘traditional’ farmer managed irrigation systems (FMIS). Thinking along the binary modernity-tradition leaves little room for the possibility that drip irrigation and FMIS could come together in a meaningful way as they place FMIS and drip irrigation in two mutually exclusive representational categories. Yet, the water users from the Khrichfa Canal, part of the Ain Bittit Irrigation System, a ‘traditional’ FMIS in Northern Morocco, opt for ‘modern’ drip irrigation as technology of their choice. To explain this apparent contradiction this PhD thesis develops an approach to rethinking the performance of drip irrigation in the context of farmer managed irrigation systems. The question “how does drip irrigation perform?” guides this research. In irrigation engineering literature the performance of drip irrigation is centred around the notion of water use efficiency – the prime task that drip irrigation is supposed to fulfil. However, to understand drip irrigation in FMIS, a more processual and less prescriptive approach to performance is explored. Drawing on actor-network approaches, the thesis understands performance as “the art of ordering the relations and interactions between people and objects, a process of ordering which emerges from practice and which results in contingent, surprising outcomes.”

This study starts by ‘unpacking’ the efficiency of drip irrigation by exploring what efficiency means, how the strong link between drip irrigation and efficiency was constructed, and what this association of drip irrigation as an efficient technology does. Because of its renowned efficiency, drip irrigation introduction is stimulated in many countries. Yet, efficiency is not an uncontested term. From the academic debate on efficiency complexity, it is clear that efficiency terminology is scale and context specific. Rather than studying drip irrigation with a pre-defined scale of analysis, this thesis focuses on how efficiencies, and their assumptions about scales and context, are used in irrigation projects and descriptions of drip irrigation performance. This PhD study critically engages with questions about efficiency and searches for alternative ways of understanding performance. To understand how drip irrigation and FMIS can come together in meaningful ways, this PhD study does not only re-define the performance of drip irrigation but likewise re-thinks conceptualisations of FMIS. FMIS are approached as dynamic entities that continuously change – which allows to see the introduction of drip irrigation as yet another change, rather than a disruption of ‘tradition’.

The farmer managed Seguia Khrichfa in Northern Morocco is selected as a case study to understand how drip irrigation performs in a FMIS with a historical analysis. The Moroccan government stimulates the introduction of drip irrigation because this efficient technology addresses problems of groundwater depletion ànd supports a growth in agricultural production. In the Khrichfa area, several individual farmers have converted to drip irrigation and the water users organisation is planning for a collective drip irrigation system. The existing drip irrigation systems and the collective plans provided fertile ground for exploring how ‘modern’ drip irrigation and ‘traditional’ FMIS can go together. This thesis begins with a literature review on the efficiency of drip irrigation in Chapter 2. Chapter 3 is an analysis of what efficiencies do in the field, how efficiencies are used to re-allocate water in (drip) irrigation projects. In Chapter 4 and 5 alternative conceptualisations of performance are explored: in Chapter 4 by analysing the intimate relation between technologies and institutions, and their capacity to mutually shape each other, and in Chapter 5 the focus lies on understanding the performance of drip irrigation as emerging from the interactions between the technology and its (potential) user.

The literature review in Chapter 2 aims to understand the scientific basis for the expectations that drip irrigation is efficient with water. Efficiency studies underscore the need for drip irrigation as a device to counter water scarcity, groundwater depletion and competition over water and align with a modernization discourse – aiming at improvement and upgrading of irrigation. The efficiency of drip irrigation is constructed at very localized experimental stations with a wide variety of efficiency terms and definitions used by different research communities. Although the term efficiency gives the impression of unity, the studies that measure and define efficiency have remarkable differences in conceptualizing water balances and measuring water flows. However, the resulting efficiency numbers are treated as if they were comparable amongst each other. This results in a widely supported consensus that drip irrigation saves water. This creation of unity might be strategic for continuation of research practices and funding, but it says little about how drip irrigation will perform in the fields of farmers. The practices of farmers are left out of the experiments reviewed in literature. Besides local farming practices more ‘context’ is left out of the equations: with water-tight plastic borders all flows in the experiments are controllable. The research on the efficiency of drip irrigation is thus very technology-centred, i.e. the performance of the technology and its capacity to bring water efficiently to plants is attributed to the material objects.

Chapter 3 shows that efficiency numbers do have influence as they embed a promise of the creation of more water. Apparently previously ‘lost’ water would be captured, thus resulting in a water ‘gain’. This is not specific for drip irrigation – the promise of water ‘gains’ is also present in other irrigation technologies and modernization projects. For example, previous modernization projects in the Ain Bittit irrigation system, of which the Seguia Khrichfa is a secondary canal, focused on lining of the infrastructure in order to re-allocate the ‘saved’ water for drinking water to the city of Meknes. All modernization projects in Ain Bittit have been preceded or accompanied by a process of re-allocating yet-to-be saved water. For example, the many actors involved in the conversion to drip irrigation all claim that the water ‘gain’ would be theirs. As this is never openly discussed, it is only when projects are implemented that competition over the ‘saved’ water arises. Yet, this competition is not brought to the open and each actor claims the ‘saved’ water, resulting on multiple claims on the yet-to-be saved water. Within the irrigation system, the ‘saved’ water mixes with the rest of the flows in the basin. This makes it 1) impossible to know how much water is actually saved, and thus how much water could be re-distributed, and 2) invisible to others who actually uses the ‘saved’ water. Only silent actors in a powerless position – like the aquifer – lose out. Chapter 3 concludes with the suggestion that not measuring actual water gains is strategic because it de-politicises re-allocations, allowing several actors to appropriate the yet-to-be-saved water without confrontations.

Chapter 4 describes the performance of technology as co-defining the water distribution in an irrigation system, and its role in defining possible solutions. The technology has a function in co-shaping institutions, which forms also depend on the distributional questions that institutions aim to tackle. For drip irrigation, this means that the introduction of drip irrigation technology is shaped through and also provokes distributional questions. Which water users are in- or excluded from the system? What are legitimate reasons for accessing water? The introduction of drip irrigation brings with it discourses on efficiency, productivity and avoidance of waste – which shape the framing of distributional questions. Surprisingly, these questions do not lead to open conflicts in Khrichfa. The conclusions of Chapter 4 suggest that this is because technologies can play a role in de-politicizing change. Suggesting new technologies or drawing old technologies into new configurations allows actors to enforce changes in the irrigation system without anyone losing face. When difficult questions on in-or exclusion are defined as issues of efficiency and modernization – and thus as progress and the way forward – these are hard to openly oppose.

Chapter 5 explores socio-technical performances of drip irrigation in the Seguia Khrichfa area by approaching performance as emerging from practice. The positivity of drip irrigation (constructed through efficiency experiments in laboratories which travelled to agricultural policies and donor-led debates) radiates on drip irrigation users and the administration and works in the field to create identities and form alliances. In Khrichfa, drip irrigation contributes to a shift towards modern, entrepreneurial and clean agriculture, and strengthens the ties between the irrigation community and the State. These are performances of drip irrigation that come into being in wider networks in which the technology interacts. In other situations (at other moments, in interaction with other actors, another environment) drip irrigation could perform in different ways. In the most extreme cases, drip irrigation does not even have to be in place physically as an object to perform. Talking about drip irrigation, aligning with drip irrigation and its discourses of efficiency and modernity also performs. Yet, the socio-technical focus on processes of network ordering hints at the fragility of the performances of drip irrigation: actors need to actively keep the network they constructed in place to maintain identities and alliances. This understanding of performance also means that drip irrigation can perform in many ways, but this does not mean that these performances can be expected in other contexts. Likewise, one cannot expect that drip irrigation is always efficient. Drip irrigation only becomes efficient through practice, when actors, technology and the environment all work towards the goal of using water efficiently.

The general discussion concludes by answering the main research question on how drip irrigation performs. Drip irrigation performs as an efficient technology, which is often translated in irrigation policies as needing less water while increasing productivities. The suggestion that water is ‘saved’ that would otherwise be ‘lost’ creates a promise of water gains which can be re-distributed. Drip irrigation also performs as network builder and creator of identities. Both modern drip irrigation and notions of performance (such as efficiency) are strategic for de-politicizing re-allocation issues. Changing water allocations via efficiency arguments or transforming institutions via technologies is attractive as it silences opposition. This thesis also highlights how performance assessments – for example based on irrigation efficiency – perform (and are performed); they re-order the relations and interactions between people and objects. Likewise, FMIS, as a category to define irrigation systems perform. Any definition or categorisation implies certain possibilities or restrictions, and the water users of the Seguia Khrichfa know well how to use these in their favour. As implications of this research for the Moroccan agricultural policy, this study suggests that it is doubtful whether drip irrigation makes available the anticipated water, as the Moroccan government is not the only actor that claims access to the ‘saved’ water. Yet, this thesis suggests that drip irrigation does help farming communities to experience that they ‘count’ in modern agriculture – though other cheaper ways of attaining this could be possible. In addition, the suggestion is made to more explicitly measure multiple performances – to celebrate their differences rather than creating a suggestion of unity. Being open to the multiple performances of drip irrigation will help to explain for whom drip irrigation works and how, and at the costs of what. The thesis concludes with a personal reflection that drip irrigation and FMIS can very well go together, at the condition that both are re-conceptualized.

A mechanistic view of drying suspension droplets
Kooij, Hanne M. Van Der; De Kerkhof, Gea T. Van; Sprakel, Joris - \ 2016
Soft Matter 12 (2016)11. - ISSN 1744-683X - p. 2858 - 2867.

When a dispersion droplet dries, a rich variety of spatial and temporal heterogeneities emerge. Controlling these phenomena is essential for many applications yet requires a thorough understanding of the underlying mechanisms. Although the process of film formation from initially dispersed polymer particles is well documented and is known to involve three main stages - evaporation, particle deformation and coalescence - it is impossible to fully disentangle the effects of particle deformation and coalescence, as these stages are closely linked. We circumvent this problem by studying suspensions of colloidal rubber particles that are incapable of coalescing. Varying the crosslink density allows us to tune the particle deformability in a controlled manner. We develop a theoretical framework of the main regimes and stresses in drying droplets of these suspensions, and validate this framework experimentally. Specifically, we show that changing the particle modulus by less than an order of magnitude can completely alter the stress development and resulting instabilities. Scanning electron microscopy reveals that particle deformability is a key factor in stress mitigation. Our model is the suspension equivalent of the widely used Routh-Russel model for film formation in drying dispersions, with additional focus on lateral nonuniformities such as cracking and wrinkling inherent to the droplet geometry, thus adding a new dimension to the conventional view of particle deformation.

Opportunistically recorded acoustic data support Northeast Atlantic mackerel expansion theory
Kooij, Jeroen vander; Fassler, S.M.M. ; Stephens, D. ; Readdy, Lisa ; Scott, B. ; Roel, Beatriz - \ 2016
ICES Journal of Marine Science 73 (2016)4. - ISSN 1054-3139 - p. 1115 - 1126.
fisheries acoustics - mackerel - North sea - scomber scombrus
Fisheries independent monitoring of widely distributed pelagic fish species which conduct large seasonal migrations is logistically complex and expensive.One of the commercially most important examples of such a species in the Northeast Atlantic Ocean is mackerel for which up to recently only an international triennial egg survey contributed to the stock assessment. In this study, we explore whether fisheries acoustic data, recorded opportunistically during the English component of the North Sea International Bottom Trawl Survey, can contribute to an improved understanding of mackerel distribution and provide supplementary data to existing dedicated monitoring surveys. Using a previously published multifrequency acoustic mackerel detection algorithm, we extracted the distribution and abundance of schooling mackerel for the whole of the North Sea during August and September between 2007 and 2013. The spatio-temporal coverage of this unique dataset is of particular interest because it includes part of the unsurveyed summer mackerel feeding grounds in the northern North Sea. Recent increases in landings in Icelandic waters during this season suggested that changes have occurred in the mackerel feeding distribution. Thus far it is poorly understood whether these changes are due to a shift, i.e. mackerel moving away from their traditional feeding grounds in the northern North Sea and southern Norwegian Sea, or whether the species’
distribution has expanded. We therefore explored whether acoustically derived biomass of schooling mackerel declined in the northern North Sea during the study period, which would suggest a shift in mackerel distribution rather than an expansion. The results of this study show that in the North Sea, schooling mackerel abundance has increased and that its distribution in this area has not changed over this period. Both of these findings provide, to our knowledge, the first evidence in support of the hypothesis that mackerel have expanded their distribution rather than moved away.
Evolutionarily advanced ant farmers rear polyploid fungal crops
Kooij, Pepijn W. ; Aanen, D.K. ; Schiøtt, M. ; Boomsma, Jacobus J. - \ 2015
Journal of Evolutionary Biology 28 (2015)11. - ISSN 1010-061X - p. 1911 - 1924.
Leucoagaricus - Attini - Basidiomycota - Cell-nuclei - Co-evolution - Fungus-growing ants - Mutualism

Innovative evolutionary developments are often related to gene or genome duplications. The crop fungi of attine fungus-growing ants are suspected to have enhanced genetic variation reminiscent of polyploidy, but this has never been quantified with cytological data and genetic markers. We estimated the number of nuclei per fungal cell for 42 symbionts reared by 14 species of Panamanian fungus-growing ants. This showed that domesticated symbionts of higher attine ants are polykaryotic with 7-17 nuclei per cell, whereas nonspecialized crops of lower attines are dikaryotic similar to most free-living basidiomycete fungi. We then investigated how putative higher genetic diversity is distributed across polykaryotic mycelia, using microsatellite loci and evaluating models assuming that all nuclei are either heterogeneously haploid or homogeneously polyploid. Genetic variation in the polykaryotic symbionts of the basal higher attine genera Trachymyrmex and Sericomyrmex was only slightly enhanced, but the evolutionarily derived crop fungi of Atta and Acromyrmex leaf-cutting ants had much higher genetic variation. Our opposite ploidy models indicated that the symbionts of Trachymyrmex and Sericomyrmex are likely to be lowly and facultatively polyploid (just over two haplotypes on average), whereas Atta and Acromyrmex symbionts are highly and obligatorily polyploid (ca. 5-7 haplotypes on average). This stepwise transition appears analogous to ploidy variation in plants and fungi domesticated by humans and in fungi domesticated by termites and plants, where gene or genome duplications were typically associated with selection for higher productivity, but allopolyploid chimerism was incompatible with sexual reproduction.

Watching paint dry: more exciting than it seems
Kooij, H.M. van der; Sprakel, J.H.B. - \ 2015
Soft Matter 11 (2015)32. - ISSN 1744-683X - p. 6353 - 6359.
latex film formation - thin liquid-films - colloidal dispersions - polymer diffusion - particle-size - cracking - coalescence - emulsion - water - deformation
With an ever-increasing demand for sustainable alternatives to solvent-borne coatings and paints, the pressure to develop aqueous alternatives that match or exceed the performance of their traditional counterparts rises. A crucial step in this sustainability challenge for the years to come is to arrive at a deep, and complete, understanding of how aqueous paints dry and form their final protective films. As it turns out, this is no minor challenge. Yet, understanding drying and film formation is a prototypical soft matter problem at heart, displaying a rich variety of complex non-equilibrium phenomena that are waiting to be understood. Watching paint dry is far from the boring activity the saying suggests.
Temperature controlled sequential gelation in composite microgel suspensions
Appel, J. ; Lange, N. de; Kooij, H.M. van der; Laar, T.X. van de; Hove, J.B. ten; Kodger, T.E. ; Sprakel, J.H.B. - \ 2015
Particle and Particle Systems Characterization 32 (2015)7. - ISSN 0934-0866 - p. 764 - 770.
attractive particles - liquid - gels
Depending on the volume fraction and interparticle interactions, colloidal suspensions can exhibit a variety of physical states, ranging from fluids, crystals, and glasses to gels. For microgel particles made of thermoresponsive polymers, both parameters can be tuned using environmental parameters such as temperature and ionic strength, making them excellent systems to experimentally study state transitions in colloidal suspensions. Using a simple two-step synthesis it is shown that the properties of composite microgels, with a fluorescent latex core and a responsive microgel shell, can be finely tuned. With this system the transitions between glass, liquid, and gel states for suspensions composed of a single species are explored. Finally, a suspension of two species of microgels is demonstrated, with different transition temperatures, gels in a sequential manner. Upon increasing temperature a distinct core–sheath structure is formed with a primary gel composed of the species with lowest transition temperature, which acts as a scaffold for the aggregation of the second species.
Coalescence, cracking, and crack healing in drying dispersion
Kooij, H.M. van der; Kool, R.H.M. de; Gucht, J. van der; Sprakel, J.H.B. - \ 2015
Langmuir 31 (2015)15. - ISSN 0743-7463 - p. 4419 - 4428.
latex film formation - glass-transition temperature - polymer diffusion - deformation - polystyrene - interfaces - coatings - surface - modes - bulk
The formation of a uniform film from a polymer dispersion is a complex phenomenon involving the interplay of many processes: evaporation and resulting fluid flows through confined geometries, particle packing and deformation, coalescence, and cracking. Understanding this multidimensional problem has proven challenging, precluding a clear understanding of film formation to date. This is especially true for drying dispersion droplets, where the particular geometry introduces additional complexity such as lateral flow toward the droplet periphery. We study the drying of these droplets using a simplified approach in which we systematically vary a single parameter: the glass transition temperature (Tg) of the polymer. We combine optical with scanning electron microscopy to elucidate these processes from the macroscopic down to the single-particle level, both qualitatively and quantitatively, over times ranging from seconds to days. Our results indicate that the polymer Tg has a marked influence on the time evolution of particle deformation and coalescence, giving rise to a distinct and sudden cracking transition. Moreover, in cracked droplets it affects the frequently overlooked time scale of crack healing, giving rise to a second transition from self-healing to permanently cracked droplets. These findings are in line with the classical Routh–Russel model for film formation yet extend its scope from particle-level dynamics to long-range polymer flow.
The material of the social: the mutual shaping of institutions by irrigation technology and society in Seguia Khrichfa, Morocco
Kooij, S. van der; Zwarteveen, M.Z. ; Kuper, M. - \ 2015
International Journal of the Commons 9 (2015)1. - ISSN 1875-0281 - p. 129 - 150.
In this paper we draw attention to the important role technology plays in co-mediating institutions, opening up some courses of action and closing off others. Irrigation studies generally recognize the importance of institutions in making technologies work, but tend to take the precise functioning of institutions for granted. Studies that analyse institutions often do not pay enough attention to the mediating role of technology in allocating benefits, risks and burdens. We show in this paper that (irrigation) institutions are moulded by and come about through the interactions between the technical and the social in dynamic and often contested processes of adaptation to changing environments. We argue that a critical understanding of what institutions do requires more explicit and detailed attention to technologies. We base this argument on a detailed historical analysis of the functioning of Seguia Khrichfa, a farmer managed irrigation scheme in Morocco. Through time, irrigation institutions in the Seguia Khrichfa have undergone transformations to match the changing demands of a heterogeneous and growing group of irrigators, an increased command area and changing cropping patterns, and the introduction of new technologies such as drip irrigation. These institutional transformations consisted of recursive cycles of modifications in technological infrastructure and the rules of allocation and distribution. Technical adaptations prompt alterations in the water rotation schedule and vice versa. We anchor our case in descriptions of a specific technology that played a crucial role in co-steering institutional change: the introduction of open/closed gates. Our analysis of the co-evolution of society and technology in shaping institutions in the Seguia Khrichfa shows how technologies become enrolled in (sometimes implicit) processes of re-negotiating relations of authority and responsibility while obscuring institutional politics.
Microbial activity in granular activated carbon filters in drinking water treatment
Knezev, A. - \ 2015
University. Promotor(en): Hauke Smidt; D. van der Kooij. - Wageningen : Wageningen University - ISBN 9789462572447 - 157
actieve kool - waterzuivering - drinkwater - organische stof - microbiële activiteiten - activated carbon - water treatment - drinking water - organic matter - microbial activities
The investigations described are carried out to analyse the microbiological processes in relation to the GAC characteristics and the removal of natural organic matter (NOM) in Granular Activated Carbon filters (GACFs) in water treatment. The main goal of the study was to obtain a qualitative description of the interactions between microbial activity and the surface characteristics of GAC. For this purpose the concentration of active bacterial biomass in GACFs, the identity and properties of the predominating bacteria and the effects of the adsorptive properties of GAC on biodegradation were studied
Paradoxale modernisering : Ede, 1945-1995: groot geworden, herkenbaar gebleven
Bloembergen-Lukkes, J.R. - \ 2014
University. Promotor(en): Pim Kooij, co-promotor(en): Anton Schuurman. - Wageningen : Wageningen University - ISBN 9789462571433 - 365
geschiedenis - modernisering - politiek - economie - demografie - cultuur - onderwijs - migratie - ruimtelijke ordening - sociologie van vrijetijdsbesteding - lokale geschiedenis - veluwe - nederland - history - modernization - politics - economics - demography - culture - education - migration - physical planning - sociology of leisure - local history - netherlands

Summary

Paradoxical Modernization

Ede, 1945-1995: Grew big, remained recognizable

After the Second World War, like many other municipalities in the Netherlands and elsewhere in the Western World, Ede experienced a period of rapid economic and population growth, of mobility, increase in scale, urbanization, better education, professionalization, individualization and democratization. Developments that may be summarized in the word modernization. I wondered if modernization is an exogenous process and did it more or less just happen, or is it a planned process or something in between. I decided that the best way to answer these questions was not to study the modernization process on a national level, but on a local level. There I hoped to find the answer on the question what possibilities people have to define their own community.

I choose the municipality of Ede as my case study for the next reasons. After 1945, the Ede municipal executive opted for growth: economic, population and employment growth. In 1962, the municipal executive formulated a goal to welcome its 100,000 resident by the year 2000, which represented a doubling of the population since the end of the war. Ede was to be transformed into the city of Ede. This milestone of 100,000 inhabitants was reached as early as 1996, 60,000 of whom lived in Ede town. In order to achieve this goal, action was needed on several fronts. The rapid growth achieved was not the result of a policy plan handed down by central government. Ede was not one of the designated development areas. Ede was not regarded as an underdeveloped area requiring a top- down targeted approach for accelerated industrialization and modernization. On the other hand, in 1945, Ede was still clearly a rural community and the town centre clearly showed characteristics of a village society. So the rapid growth meant changes in different policy sectors.

Ede easily attracted new residents and employment opportunities as a result of its strategic location in the middle of the Netherlands, its good infrastructure and sufficient space. What it did need, however, was the development of housing estates and industrial estates including the necessary infrastructure and the development and expansion of, for example, education facilities and leisure amenities. In a predominantly Protestant community, this raised questions about the persuasion of these types of amenities and led to debates on, if actually desirable, the type of socio-cultural policy most appropriate for local government. Rapid expansion of a community may be perceived as a threat to the characteristics of that society. This question made Ede an extra interesting subject for research. In the case of Ede it was justifiable to assume that tensions would have arisen between the rural and urban ambitions and between Christian and secular developments. The municipal authority is involved in the developments and decision-making process relating to all the elements of the public domain, which is why it was chosen as the focus for this research.

The policy decisions required in the different areas to facilitate growth are by their nature intertwined. The construction of housing estates and business premises conflict with the interests of the agricultural sector and nature conservation. The arrival of new residents can change the social, political and religious composition of the population, resulting in consequences for how society is organized and for the future local political constellation and vice versa. Every decision must take what has occurred in other areas into account and will, in turn, have consequences for adjacent domains. For these reasons a choice was made for modernization as theoretical concept. Chapter one contains a historiographical discussion of this concept and an elaboration of how this concept has been applied to this research. In line with Schuyt and Taverne, I have chosen not to provide modernization in advance with a specific interpretation by adding ‘controlled’, ‘contested’ or ‘reflexive’. For the research, four policy areas have been selected for further investigation: spatial planning, education, guest workers/migrants and leisure facilities. As an introduction to the chapters on the developments in Ede, chapter two contains a broad outline of the national developments in which the local developments took place. Subsequently, in chapter three I discuss the way in which the modernization process was made visible in the composition of the municipal executive, including its chairpersons over a period of fifty years. Politicians not only partly determine which choices are made in the modernization process, but are also subject to this process themselves both at party and individual level. In this sense, through its decisions the political establishment in no small way contributes to determining its own future and, in turn, the composition of the municipal council and executive. The choices for more or

less growth, for public-authority or private-authority schools , for providing public amenities or not, et cetera influence who will choose Ede as a place of residence and work. In this way, secularization manifests itself in changes in the population composition and the demand for specific amenities, as well as at the level of the political composition of the municipal council and the individual councillors. As a result of the population growth, by 1966 the newcomers held the majority of the seats on the council. However, the original population of Ede managed to control the executive positions for much longer. Democratization, individualization and secularization led to an increase in the number of political parties represented on the council and enhanced pluralism. Compared to politics at national level, both women’s emancipation and the professionalization of councillors clearly had a delayed start. As was the case at national level the larger parties lost ground, although the SGP (Reformed Political Party) formed an exception in Ede.

The main theme of chapter four is spatial planning. Ede has profited considerably from the migration of residents and employment opportunities from the Randstad. Ede’s central location put it in a strategic position to benefit from national developments on spatial planning. The size of the municipality ̶ Ede being one of the largest in the Netherlands ̶ , the good infrastructure and the presence of the Veluwe National Park made Ede a popular place of residence and business. This remained the case even after, from the start of the 1960s, the provincial and national governments tried to curb the drift to Ede. As a result of its many qualities, Ede was able to achieve its growth ambitions and disregard the limiting measures imposed by higher government levels. In relation to nature conservation, Ede stayed more in line because the municipal executive regarded the Veluwe National Park as one of the attractive aspects of living in Ede. In respect to agriculture, the municipal executive chose for, on the one hand, an uncompromising policy to develop housing and business premises at the expense of farmland, while, on the other hand, applying a non-interference policy for the agricultural sector and business operations. Both small farmers and the strong growth in intensive animal husbandry could count on an accommodating local government. It was the national government which, as a result of the high levels of environmental pollution, designated the Gelderland Valley as a Spatial Planning and Environment area (ensuring spatial planning was combined with the environmental aspects). This, in turn, forced the municipal authority to impose regulatory measures on the agricultural sector in its spatial planning policies.

The policy choices in relation to the educational facilities are discussed in chapter five. What is conspicuous here is the clear commitment on the part of the Christian political parties to maintain the Christian character of the education. In the 1950s, this commitment could also count on the support of the Christian councillors representing the PvdA (Labour Party). It was not until the early 1960s that all the PvdA councillors supported the VVD (People’s Party for Freedom and Democracy) in its struggle

to increase the number of public-authority schools. In the meantime, Protestant Ede had managed, under the leadership of the ARP (Anti-Revolutionary Party) aldermen, to establish broad, and partly above municipality level, private-authority denominational schools. In achieving this, the ARP (Anti- Revolutionary Party) politicians were able to make use of their extensive network, which included national politicians. It was only in the early 1980s that secular Ede achieved a long-cherished goal with the opening of a public-authority neutral secondary school. The presence of a broad range of Protestant-Christian educational facilities is one of the explanations why Ede’s expansion did not lead to a drop, in percentage terms, of the Orthodox-Christian share of the vote. These parties were, however, practically always kept outside the coalition. Nevertheless, they managed to profit from the educational policies implemented by the coalition parties CHU (Christian Historical Union) and ARP (Anti-Revolutionary Party), and later by the CDA (Christian Democratic Appeal). These parties were not, however, rewarded for this policy as they were confronted with continuous and steady losses at the polls. Illustrative of this development was also the establishment in the 1970s of a number of Protestant Reformed primary schools and the establishment of a Protestant-Christian School Advisory Service in 1984. The long-term opposition to a more secular organization of society was also expressed in the opposition until the start of the 1970s to abolishing the dismissal of married teachers.

Ede’s growth did not only bring an influx of new residents from the rest of the Netherlands to the Veluwe. The shortage of unskilled workers, which continued to increase during the 1960s in the Netherlands, also resulted in the arrival of guest workers in Ede. Chapter six discusses the attitude of the political establishment towards this population group, whose stay was initially expected to be only temporary. It quickly became apparent that their unfamiliarity with our country, language, customs and laws in combination with their low wages and, for the most part, low level of education gave rise to a need for social assistance and specific facilities. The municipal executive did not, however, make use of the possibility to participate in the Migrant Workers’ Assistance Foundation that was established in Gelderland in the 1960s and in which the municipal executives of Apeldoorn and Arnhem participated. The Ede municipal executive maintained the view, as did other places in the Netherlands, that the

reception of this population group and the facilitating or provision of specific facilities was not the task of government —and most certainly not in the area of religion. In relation to this last point, the constitutional separation of church and state was invariably used as argumentation. Although, in practice in the Netherlands, and this includes Ede, up to that point had not been so strictly adhered to as was preached in Ede. It was only at the end of the 1970s that the first careful steps were taken to arrange for the required facilities. The municipal executive disregarded an official report in 1977 by Ede’s own Sociographical Department, in which migrant workers were considered one of the minority groups in the Netherlands and in which specific mention was made of the role of government in the origination of the problems confronting this population group. The decision of the national government in 1984 to transfer policy on minorities to local government forced the municipal executive to set down its own policy. When social unrest occurred surrounding the desire of and initiatives by the Moroccan and Turkish communities for their own place of prayer, the municipal executive slowly changed its attitude from a wait-and-see approach into an active approach in which a reasonably acceptable solution was sought in consultation with all the parties involved. The strong position of the SGP (Reformed Political Party) in local politics could present an explanation for the fact that in this period the extreme right in Ede, in contrast to national level, never achieved the electoral threshold.

Growth also places demands on leisure facilities. In the previous topics, especially in relation to the educational facilities and the facilities for migrant workers, there was an ongoing discussion in the background about how big the role of government should be in society. In confessional circles, but also within the VVD (People’s Party for Freedom and Democracy), an ideological preference prevailed for small government, meaning, where possible, the initiative should be left to the community or the individual respectively. Government spending on leisure activities was particularly sensitive in the Protestant-Christian parties. The SGP (Reformed Political Party), on principal, held the opinion that the government should not spend public money on these types of activities. The development of sport fields/sport halls and the accommodation of sports clubs could, however, count on the support of the majority of the council and certainly also of the municipal executive. In the 1950s and 1960s the aldermen of the PvdA (Labour Party), VVD (People’s Party for Freedom and Democracy) and ARP (Anti-Revolutionary Party) were great sport enthusiasts. Subsidies for cultural activities were more sensitive as theatre and opera had been a taboo for a long time within segments of the Protestant- Christian parties and, particularly, within the SGP (Reformed Political Party). If it was, nevertheless, decided to provide funding to support organizations or initiatives, then it was chosen for a strong involvement by the municipality, for example through ownership and tenures. This was an attempt by the municipal executive to exercise more control over the operations and the use of subsidies. At the same time, the municipal executive had a preference for the commercial use of, for example, a swimming pool or a theatre because this presented the possibility of keeping the public funding to a minimum. Particularly this involvement in a commercial organization gave rise, once again, to criticism within the council and within the community because commercialism with the help of public money was considered inappropriate for government and unfair competition. Ultimately, in the middle of the 1980s, the municipal executive distanced itself from the commercial operations by awarding a fixed subsidy amount based on agreements relating to the services provided to the community.

Reflecting on the fifty year period researched, two cut-off points can be established in the modernization process in Ede. The first period runs from 1945 to 1966 and is characterized by growth and tradition. The prevailing philosophy was that despite the choice for growth the Protestant-Christian character of the municipality should and could be maintained. This is illustrated in the development of a broad and above municipal level provision of private-authority Protestant-Christian educational facilities, in the commitment to non-interference in the agricultural sector including keeping the peasants, and in the conservative policy on developing cultural activities for the leisure sector.

However, the growth did strengthened aspects such as secularization, professionalization, geographical and social mobility, individualization and democratization: the modernization process continually resulted in changes in society and in the population composition and was not solely restricted to what was desirable or planned.

The second period runs to 1978 and can be characterized with the terms: change and debate.

The municipal policy was examined more critically. For example, the city-forming plans were considered undesirable both by the original population and the newcomers. Maintaining the smallness and a more rural character proved to be attractive aspects for Ede. At the same time, the demand for a more pluralistic and broader provision of social and cultural activities increased. In this second period, the non-interference policy in relation to agricultural developments except in the case that agricultural lands were required for housing and business premises, encountered opposition when the negative effects of the continuous expansion in the intensive animal husbandry for the ecology and

environment became more apparent. In addition, the arrival of migrant workers and with them Islam

into this predominantly Protestant-Christian community became more problematic during this period. As a consequence of unemployment and family reunification, more pressure was put on the municipal authorities for assistance and the need for a place of prayer for the Muslim community strengthened.

The societal and economic changes led to a more pluralistic political landscape. The six parties were confronted with increasing competition from new political parties, including the Boerenpartij (Farmers’ Party) which was the first to profit from the discontent. Only the SGP

(Reformed Political Party) managed to hold onto its share of the vote. The third period is characterized by the development of a new political situation and the search for a new political balance. The municipal executive was forced by the national government to curb the intensive animal husbandry.

The ARP (Anti-Revolutionary Party) had to part with the education portfolio and, finally, Ede got a public-authority neutral secondary school, the Pallas Athene. It was a long journey, but the Muslim community also received its own place of prayer. At a time when societal opposition to the building of a mosque appeared to favour the national extreme-right political parties and movements, the municipal executive opted to work with the Muslim groups to find a solution acceptable to all parties. The municipality distanced itself from the business operations in how it financed organizations such as swimming pools, the theatre and events such as the Week of the Heather.

What are the answers to my questions I posed in the beginning: is modernization at the local level more of less an exogenous process, can it be planned, or have local politicians enough opportunities to make a difference? When compared to the national developments it holds true for Ede that the 1950s was certainly a dynamic period, but it is also true to say that a Protestant-Christian community such as Ede required more time to shape its growth ambition so that old and new, conservative and progressive, and religious and secular could achieve a new balance and compromise. The changes were neither imposed from outside nor according to plan. The paradoxical outcome of the modernization process is that it has led to the further convergence of the local with the national developments, but it has at the same time ensured the survival of local characteristics.

Partially, these are characteristics that have consciously been or were able to be preserved by politicians, such as the predominantly Protestant-Christian education facilities and a conservative policy towards the socio-cultural domain. This policy has not, per definition, turned out favourably for the supporting political parties. It was the SGP (Reformed Political Party) and not the governing parties CHU (Christian Historical Union) and ARP (Anti-Revolutionary Party) (and later the CDA (Christian Democratic Appeal) that managed to hold onto its voters, even though the Protestant-Christian character of the municipality was the reason why a segment of the newcomers chose for Ede. Their votes did not strengthen the confessional parties at the centre of the political spectrum; it was precisely the orthodox element that benefitted, which was illustrated by the arrival of the RPF (Reformed Political Federation/GPV (Reformed Political Union). Other characteristic elements are independent of the local political policy and have ensured that Ede has become and remains a desirable place of residence and business. Its central location on the Veluwe, the good infrastructure, and the size of the municipality stimulated and made growth possible. Ede was a municipality with adequate facilities and the amenities it lacked could be found in the nearby Randstad and Arnhem.

The Veluwe National Park also forms a large, green and tranquil back garden.

Modernization was not imposed upon Ede, contrary to what Van Deursen notes in the case of Katwijk. Even so no controlled modernization for Ede, as Van Vegchel describes for Emmen. Like Zwemer states for Zeeland, local politics in Ede has been able to make a difference within the national developments and governmental guidelines. The national government only intervened and imposed their policy at the moment local political choices led to negative effects beyond the municipal boundaries. In accordance with the findings of Schuyt and Taverne the development in Ede was not the result of a ‘grand design’, not even of local politicians. Ede shows quite nice the paradox of modernization. Despite the creation of uniformity in the ongoing process of national integration and globalization, the paradox is that contradictory movements are possible that contribute to ensuring that the unique character of the area can be preserved, even if this characterization is also subject to change.

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