De vrijetijdsindustrie in stad en land. Een studie naar de markt van belevenissen

Political Scienc

Transforum system innovation towards sustainable food. A review

Innovations in the agri-food sector are needed to create a sustainable food supply. Sustainable food supply requires unexpectedly that densely populated regions remain food producers. A Dutch innovation program has aimed at showing the way forward through creating a number of practice and scientific projects. Generic lessons from the scientific projects in this program are likely to be of interest to agricultural innovation in other densely populated regions in the world. Based on the executed scientific projects, generic lessons across the whole innovation program are derived. We found that the agricultural sector requires evolutionary rather than revolutionary changes to reshaping institutions. Measuring sustainability is possible against benchmarks and requires stakeholder agreement on sustainability values. Results show the importance of multiple social views and multiple stakeholder involvement in agricultural innovation. Findings call for flexible goal rather than process-oriented management of innovation. Findings also emphasise the essential role of profit in anchoring sustainable development in business. The results agree with concepts of evolutionary innovation. We conclude that there is no single best solution to making the agri-food sector more sustainable densely populated areas, but that the combination of a range of solutions and approaches is likely to provide the best way forward

SARS-Coronavirus Replication/Transcription Complexes Are Membrane-Protected and Need a Host Factor for Activity In Vitro

SARS-coronavirus (SARS-CoV) replication and transcription are mediated by a replication/transcription complex (RTC) of which virus-encoded, non-structural proteins (nsps) are the primary constituents. The 16 SARS-CoV nsps are produced by autoprocessing of two large precursor polyproteins. The RTC is believed to be associated with characteristic virus-induced double-membrane structures in the cytoplasm of SARS-CoV-infected cells. To investigate the link between these structures and viral RNA synthesis, and to dissect RTC organization and function, we isolated active RTCs from infected cells and used them to develop the first robust assay for their in vitro activity. The synthesis of genomic RNA and all eight subgenomic mRNAs was faithfully reproduced by the RTC in this in vitro system. Mainly positive-strand RNAs were synthesized and protein synthesis was not required for RTC activity in vitro. All RTC activity, enzymatic and putative membrane-spanning nsps, and viral RNA cosedimented with heavy membrane structures. Furthermore, the pelleted RTC required the addition of a cytoplasmic host factor for reconstitution of its in vitro activity. Newly synthesized subgenomic RNA appeared to be released, while genomic RNA remained predominantly associated with the RTC-containing fraction. RTC activity was destroyed by detergent treatment, suggesting an important role for membranes. The RTC appeared to be protected by membranes, as newly synthesized viral RNA and several replicase/transcriptase subunits were protease- and nuclease-resistant and became susceptible to degradation only upon addition of a non-ionic detergent. Our data establish a vital functional dependence of SARS-CoV RNA synthesis on virus-induced membrane structures

The Chitobiose-Binding Protein, DasA, Acts as a Link between Chitin Utilization and Morphogenesis in Streptomyces Coelicolor

Streptomycetes are mycelial soil bacteria that undergo a developmental programme that leads to sporulating aerial hyphae. As soil-dwelling bacteria, streptomycetes rely primarily on natural polymers such as cellulose, xylan and chitin for the colonization of their environmental niche and therefore these polysaccharides may play a critical role in monitoring the global nutritional status of the environment. In this work we analysed the role of DasA, the sugar-binding component of the chitobiose ATP-binding cassette transport system, in informing the cell of environmental conditions, and its role in the onset of development and in ensuring correct sporulation. The chromosomal interruption of dasA resulted in a carbon-source-dependent vegetative arrest phenotype, and we identified a second DasR-dependent sugar transporter, in addition to the N-acetylglucosamine phosphotransferase system (PTS(GlcNAc)), that relates primary metabolism to development. Under conditions that allowed sporulation, highly aberrant spores with many prematurely produced germ tubes were observed. While GlcNAc locks streptomycetes in the vegetative state, a high extracellular concentration of the GlcNAc polymer chitin has no effect on development. The striking distinction is due to a difference in the transporters responsible for the import of GlcNAc, which enters via the PTS, and of chitin, which enters as the hydrolytic product chitobiose (GlcNAc(2)) through the DasABC transporter. A model explaining the role of these two essentially different transport systems in the control of development is provided

Grassroots Creative Hubs: Urban Regeneration, Recovered Industrial Factories and Cultural Production in Buenos Aires and Rio de Janeiro

This chapter examines the nature, functioning and politics of grassroots creative hubs as contained in refurbished industrial factories. The renewal and transformation of factories into arts and cultural venues has been a key feature of post-industrial urbanism in the last three decades. Examples abound across the world, from railway and power stations to post office buildings and chocolate factories, these recovered infrastructures have been re-signified as cultural facilities – performing or multi-arts centres, galleries, cultural centres, creative economy laboratories, incubators and museums. These initiatives, be that they are led by local governments or community groups, are part of broader urban strategies for revitalising historical centres, revalorising cultural heritage and creating work opportunities as well as resources for tourism and business investment. But can a factory building be considered a creative hub? Does the materiality of these urban artefacts provide a solution to the oftentransient nature of ephemeral cultural urbanism? Refurbishing old industrial factories and warehouses for cultural use and creative production has been the subject of much investigation since the 1980s-1990s, mainly through the study of culture-led urban regeneration and gentrification (Zukin, 1989; Montgomery, 1995; Evans and Shaw, 2004; Mommaas, 2004; Pratt, 2009), and more recently, creative industry clusters and districts (Evans, 2009; Zukin and Braslow, 2011; O’Connor and Gu, 2012). These studies have pointed out the problems that arise from the organisation, management and long-term sustainability of converted industrial sites, as well as from the policy uses and abuses that often pave the way to real-estate development and social displacement. Drawing on insights from urban sociology and critical geography, the chapter conducts a case-study analysis of two cultural and creative economy factories in Latin America: Fábrica Bhering in Rio de Janeiro, Brazil, and IMPA, la Fábrica Cultural in Buenos Aires, Argentina. The chapter is comprised of three sections: the first discusses whether recovered industrial factories can be thought of as creative hubs in relation to ephemeral cultural urbanism; the second examines the two case-studies in the context of Brazil and Argentina; and the third offers concluding remarks. Overall the chapter contributes a Latin American perspective on culture-led urban regeneration to the study of creative hubs. Particularly, grassroots creative initiatives of urban renewal are presented as an alternative to the exclusionary gentrification processes to which creative hubs and other territorial forms of creativity are often related to, in times largely shaped by neoliberal operations driven by real-estate interests and alliances between political and economic urban elites

Conversion of Mature Human β-Cells Into Glucagon-Producing α-Cells

Conversion of one terminally differentiated cell type into another (or transdifferentiation) usually requires the forced expression of key transcription factors. We examined the plasticity of human insulin-producing β-cells in a model of islet cell aggregate formation. Here, we show that primary human β-cells can undergo a conversion into glucagon-producing α-cells without introduction of any genetic modification. The process occurs within days as revealed by lentivirus-mediated β-cell lineage tracing. Converted cells are indistinguishable from native α-cells based on ultrastructural morphology and maintain their α-cell phenotype after transplantation in vivo. Transition of β-cells into α-cells occurs after β-cell degranulation and is characterized by the presence of β-cell–specific transcription factors Pdx1 and Nkx6.1 in glucagon+ cells. Finally, we show that lentivirus-mediated knockdown of Arx, a determinant of the α-cell lineage, inhibits the conversion. Our findings reveal an unknown plasticity of human adult endocrine cells that can be modulated. This endocrine cell plasticity could have implications for islet development, (patho)physiology, and regeneration

Super diversity and city branding: Rotterdam in perspective

As many other cities around the world, Rotterdam has been investing in improving its image to stimulate urban development and to attract visitors, residents and investors. In particular, during the last 15 years the municipality of Rotterdam has intensified its attempts to develop a ‘brand’ that fits the ‘new Rotterdam’, which was gradually rebuilt after destructive bombardments during the Second World War (Riezebos 2014). In 2014 Rotterdam was ranked 8th by ‘Rough Guide’ in the list of ‘Top 10 Cities to See’, whereas the ‘New York Times’ listed Rotterdam in the top 10 of 52 Places to Go. These rankings demonstrate Rotterdam’s success in repositioning itself, using the physical interior of the city as a key element in its branding strategy.</p

Constitutive expression of ftsZ overrides the whi developmental genes to initiate sporulation of Streptomyces coelicolor

The filamentous soil bacteria Streptomyces undergo a highly complex developmental programme. Before streptomycetes commit themselves to sporulation, distinct morphological checkpoints are passed in the aerial hyphae that are subject to multi-level control by the whi sporulation genes. Here we show that whi-independent expression of FtsZ restores sporulation to the early sporulation mutants whiA, whiB, whiG, whiH, whiI and whiJ. Viability, stress resistance and high-resolution electron microscopy underlined that viable spores were formed. However, spores from sporulation-restored whiA and whiG mutants showed defects in DNA segregation/condensation, while spores from the complemented whiB mutant had increased stress sensitivity, perhaps as a result of changes in the spore sheath. In contrast to the whi mutants, normal sporulation of ssgB null mutants—which fail to properly localise FtsZ—could not be restored by enhancing FtsZ protein levels, forming spore-like bodies that lack spore walls. Our data strongly suggest that the whi genes control a decisive event towards sporulation of streptomycetes, namely the correct timing of developmental ftsZ transcription. The biological significance may be to ensure that sporulation-specific cell division will only start once sufficient aerial mycelium biomass has been generated. Our data shed new light on the longstanding question as to how whi genes control sporulation, which has intrigued scientists for four decades

A Uniform Genomic Minor Histocompatibility Antigen Typing Methodology and Database Designed to Facilitate Clinical Applications

BACKGROUND: Minor Histocompatibility (H) antigen mismatches significantly influence the outcome of HLA-matched allogeneic stem cell transplantation. The molecular identification of human H antigens is increasing rapidly. In parallel, clinical application of minor H antigen typing has gained interest. So far, relevant and simple tools to analyze the minor H antigens in a quick and reliable way are lacking. METHODOLOGY AND FINDINGS: We developed a uniform PCR with sequence-specific primers (PCR-SSP) for 10 different autosomal minor H antigens and H-Y. This genomic minor H antigen typing methodology allows easy incorporation in the routine HLA typing procedures. DNA from previously typed EBV-LCL was used to validate the methodology. To facilitate easy interpretation for clinical purposes, a minor H database named dbMinor (http://www.lumc.nl/dbminor) was developed. Input of the minor H antigen typing results subsequently provides all relevant information for a given patient/donor pair and additional information on the putative graft-versus-host, graft-versus-tumor and host-versus-graft reactivities. SIGNIFICANCE: A simple, uniform and rapid methodology was developed enabling determination of minor H antigen genotypes of all currently identified minor H antigens. A dbMinor database was developed to interpret the genomic typing for its potential clinical relevance. The combination of the minor H antigen genomic typing methodology with the online dbMinor database and applications facilitates the clinical application of minor H antigens anti-tumor targets after stem cell transplantation