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REDD+ : If communities are the solution, what is the problem?
No full textWhile mainstream academic literature over the past ten years has tended to identify commercial and industrialized agriculture as the primary driver of deforestation, national plans for REDD+ (as exemplified by proposals to the Forest Carbon Partnership Facility for funding) focus strongly on ‘communities’ and local actors. This is partly to ensure that communities are not harmed by the program, and may benefit from it; but the documents show that in most cases they are in fact envisaged as the primary actors in the REDD+ implementation. In concordance with this, most of the national proposals identify small scale local actors as the agents behind deforestation much more often than large scale outside actors. Moreover, most assign more weight to REDD+ activities directed to small scale actors than even their own analysis of drivers would imply, quite apart from global understanding about who is responsible for forest loss. We suggest that this seeming policy inconsistency can be explained through an understanding of problem framing. We show that the ‘communities’ narrative may implicitly rest on earlier, now largely discredited explanations of the causes of deforestation (shifting cultivation and other traditional practices). However this narrative is attractive today from a variety of other positions, and we suggest that it represents a policy case of a solution looking for a problem.</p
Wild rodents and insectivores as carriers of pathogenic Leptospira and Toxoplasma gondii in The Netherlands
No full textSmall mammals such as rodents can to carry zoonotic pathogens. Currently, there is impaired knowledge on zoonotic pathogens in rodents and insectivores in the Netherlands. This limits opportunities for preventive measures and complicates risk-assessments for zoonotic transmission to humans. Leptospira spp. and Toxoplasma gondii are present on a list of prioritized emerging pathogens in the Netherlands and were therefore the focus of this study. Both pathogens have the ability to survive under moist environmental conditions. In total, a group of 379 small mammals (rodents & insectivores) were tested on pathogenic Leptospira spp., and 312 on T. gondii. Rodents and insectivores were trapped at various sites, but mostly on pig and dairy farms throughout the country. Over five percent of the animals (5.3%, n = 379) tested positive for Leptospira DNA, and five of the animals (1.6%, n = 312) tested were positive for T. gondii DNA. The animals positive for T.gondii were all brown rats and the ones for Leptospira spp. were various species. Our results show that insectivores and rodents might be used as an indicator for the environmental contamination and/or the contamination in wildlife for Leptospira spp.</p
Positioning of systemic intermediaries in sustainability transitions : Between storylines and speech acts
No full textHow do systemic intermediaries obtain legitimate roles for themselves in innovation systems and transition processes? This is still an understudied question in the study of systemic intermediaries. We start from the observation that roles, or positions, are not given, but emerge in interactions as a negotiated set of rights and obligations. Inspired by positioning theory, which has its roots in symbolic interactionism, we analyse how positions are invoked in the actors’ various actions and statements (‘speech acts’) and how they draw from the mutually constructed narratives (‘storylines’) that enable and constrain the range of possible positions. We analyse, over time, the positioning of three Dutch systemic intermediaries in agriculture, energy production, and healthcare. We conclude that systemic intermediaries move together with the promise of the field and, as a consequence, have to reposition themselves. In different phases, they both profit and suffer from the dilemma between initiating and sustaining innovative systemic changes.</p
A data-driven methodology reveals novel myofiber clusters in older human muscles
No full textSkeletal muscles control posture, mobility and strength, and influence whole-body metabolism. Muscles are built of different types of myofibers, each having specific metabolic, molecular, and contractile properties. Fiber classification is, therefore, regarded the key for understanding muscle biology, (patho-) physiology. The expression of three myosin heavy chain (MyHC) isoforms, MyHC-1, MyHC-2A, and MyHC-2X, marks myofibers in humans. Typically, myofiber classification is performed by an eye-based histological analysis. This classical approach is insufficient to capture complex fiber classes, expressing more than one MyHC-isoform. We, therefore, developed a methodological procedure for high-throughput characterization of myofibers on the basis of multiple isoforms. The mean fluorescence intensity of the three most abundant MyHC isoforms was measured per myofiber in muscle biopsies of 56 healthy elderly adults, and myofiber classes were identified using computational biology tools. Unsupervised clustering revealed the existence of six distinct myofiber clusters. A comparison with the visual assessment of myofibers using the same images showed that some of these myofiber clusters could not be detected or were frequently misclassified. The presence of these six clusters was reinforced by RNA expressions levels of sarcomeric genes. In addition, one of the clusters, expressing all three MyHC isoforms, correlated with histological measures of muscle health. To conclude, this methodological procedure enables deep characterization of the complex muscle heterogeneity. This study opens opportunities to further investigate myofiber composition in comparative studies.</p
Risk benefit analysis of botanical varieties growing in the Mediterranean region
No full textDespite the long history of use of medicinal plants for the treatment and prevention of diseases, the safety of botanicals and botanical preparations is not certain, since some of the contained bioactive phytochemicals can induce undesired effects. Thus, there is need to assure that the risks of the use of botanicals and botanical preparations do not outweigh the benefits. The aim of the present thesis was to reveal potential health benefits and hazards of 18 botanical varieties grown in the Mediterranean region, that are used traditionally for the treatment and prevention of several health conditions, using a series of in vitro bioassays. Chapter 1 provides background information about the use of botanicals for medicinal purposes, the traditional use and pharmacological properties of the 18 selected botanical varieties, as well as the beneficial and toxicological endpoints selected for a qualitative risk-benefit evaluation. In Chapter 2, an overview of the available in vitro bioassays, suitable for the detection of beneficial and adverse effects of botanicals, botanical preparations and their active constituents and the characteristics that make these assays valuable tools for a qualitative risk-benefit assessment, is presented. The pitfalls of bioassay use are also highlighted, discussing among others the factors that may generate false-positive or false-negative results and the limitations in the extrapolation of in vitro data to the in vivo situation. Several in vitro bioassays were applied to reveal the potential benefits and hazards of the 18 selected botanical varieties. Methanol extracts compatible with in vitro bioassays were prepared and tested in the EpRE-LUX (Chapter 3) and the PPARγ CALUX® (Chapter 4) reporter gene assays. Results obtained revealed that half of the tested extracts, are able to exert a potential chemopreventive action via activation of EpRE mediated gene expression, while most of the tested extracts (16 out of 18) may contribute to potential health benefits via the activation of PPARγ mediated gene expression. LC-MS analysis combined with MAGMa (MS Annotation based on in silico Generated Metabolites) software was applied in order to facilitate tentative identification of the active constituents within selected active extracts. Many active ingredients of the methanol extracts from Juglans regia, Rhamnus frangula and Urtica dioica were revealed, albeit in low concentrations, in the respective extracts. The presence of many compounds exerting the same activity and/or synergistic effects between the different constituents, could explain the full potential detected for the extract as a whole. The possibility that the benefits of these botanical preparations would be contraindicated by potential hazards, was also investigated. In Chapter 5, the potential estrogenic activity of the extracts was assessed in the ERα CALUX® assay resulting 13 extracts that tested positive. The zebrafish embryotoxicity test (ZET), used to reveal potential developmental toxicity, resulted in a concentration dependent drop in the GMS (general morphology score) when zebrafish embryos were exposed to Rhamnus frangula, Ruta graveolens and Achillea millefolium extracts. For the extracts from Rhamnus frangula and Achillea millefilium this drop in the GMS might be ascribed to toxicity, in contrast to the extract from Ruta graveolents that shows specific in vitro developmental toxicity. In Chapter 6, the potential genotoxicity of the extracts was tested using the AMES test. The extracts from Ruta graveolens, Fumaria officinalis and Juglans regia tested positive for mutagenicity. These results were combined with the all data obtained in Chapters 3, 4 and 5, and with information derived from the EFSA compendium of botanicals containing substances that may raise a concern, enabling an initial qualitative risk-benefit assessment for the 18 Mediterranean botanicals. For some of the botanicals, the risks clearly outweigh the potential benefits, as in the case of the extracts that tested positive for developmental toxicity and mutagenicity, for others it is not possible to come to a conclusion based on the obtained data and for others, especially for Urtica dioica L. and potentially also Equisetum arvense L., Taraxacum officinale and Veronica officinalis L., further development into functional food ingredients would be indicated, focussing in future studies on their further safety assessment and their potential to activate PPARy which could be of interest for therapeutic effects in type II diabetes mellitus. Chapter 7 summarizes the results obtained in the present thesis and provides the overall discussion and future perspectives, concluding on the value of the results obtained from in vitro bioassays in potential (pre)clinical testing strategies to support the selection of promising candidate botanicals and/or their extracts for the development of functional food ingredients
Necessity or choice: women’s migration to artisanal mining regions in eastern DRC
No full textWomen have long remained invisible in representations of artisanal mining in eastern Democratic Republic of Congo. Based on original field data, this paper seeks to fill that gap. It shows how women come to mining sites with the hope of finding a degree of security, economic possibilities and the start of a new life. Contrary to what dominant discourses on the “resource curse” and sexual violence towards women have suggested, women may find a degree of protection in mining areas. We take the analysis beyond the “push” and “pull” factors with which migration is usually explained, to understand women’s motivation to move into mining areas as complex and changing. The study situates women’s movement to the mines within their life trajectories which are shaped by violence and various forms of insecurity. The notion of social navigation is brought in to understand how they cope with gender discrimination, challenges and risks in the mining economy. The paper shows how push and pull factors merge over time and how some women succeed in creating new sources of revenue and manage to mitigate the situation of vulnerability in which they find themselves.</p
Tuning the interactions in multiresponsive complex coacervate-based underwater adhesives
No full textIn this work, we report the systematic investigation of a multiresponsive complex coacervate-based underwater adhesive, obtained by combining polyelectrolyte domains and thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) units. This material exhibits a transition from liquid to solid but, differently from most reactive glues, is completely held together by non-covalent interactions, i.e., electrostatic and hydrophobic. Because the solidification results in a kinetically trapped morphology, the final mechanical properties strongly depend on the preparation conditions and on the surrounding environment. A systematic study is performed to assess the effect of ionic strength and of PNIPAM content on the thermal, rheological and adhesive properties. This study enables the optimization of polymer composition and environmental conditions for this underwater adhesive system. The best performance with a work of adhesion of 6.5 J/m2 was found for the complex coacervates prepared at high ionic strength (0.75 M NaCl) and at an optimal PNIPAM content around 30% mol/mol. The high ionic strength enables injectability, while the hydrated PNIPAM domains provide additional dissipation, without softening the material so much that it becomes too weak to resist detaching stress.</p
Partitioning main carbon pools in a semi-deciduous rainforest in eastern Cameroon
No full textTropical forests contribute to climate change mitigation by absorbing carbon from the atmosphere and storing this in biomass and soil organic matter. However, there is still considerable uncertainty about the above- and belowground quantity and distribution of carbon stocks in African forests. Here, we evaluate how different carbon pools (aboveground live biomass, aboveground dead biomass, belowground biomass) contribute to total carbon stocks, and how different carbon components (e.g. large trees, understorey trees, coarse woody debris, roots, soil organic carbon etc.) contribute to carbon pools and total carbon stocks. We evaluated data of extensive inventories within 30 1-ha plots spanning the terra-firme semi-deciduous forest in eastern Cameroon. Hence, the plots were placed at a mean distance of 1 km from the nearest plot and we analyzed the data using variation partitioning, linear regressions and correlation tests. We found that the terra-firme semi-deciduous forests store 283.97 ± 51.42 Mg C ha−1. The aboveground biomass pool, with a carbon stock of 180.99 ± 25.8 Mg C ha−1, mostly explained variation in total carbon stocks (R2 = 0.79). From all aboveground biomass components, carbon in large trees was most strongly correlated with total carbon stocks. The second most important carbon pool was belowground carbon (on average 85.06 ± 16.86 Mg C ha−1; R2 = 0.78), mainly explained by coarse root carbon. Carbon in dead biomass had only a small contribution to total carbon stocks (R2 = 0.04). Hence, our results indicate that aboveground live biomass is a good predictor for variation in total carbon storage within this semi-deciduous terra-firme forest. However, aboveground live carbon and belowground carbon and their interactions explained most of the variation in total carbon stock, indicating that a whole-ecosystem approach is necessary for a full understanding of the carbon cycle.</p
Visualizing large-scale flow using synthetic aperture PIV
No full textAbstract: We discuss the application of synthetic aperture particle image velocimetry for measuring the flow around human swimmers using small bubbles as tracer. We quantify the two-dimensional projection of the velocity field in planes perpendicular to the viewing direction of an array of six cameras. With help of simulations, modelled after the experiment, we address questions about depth selectivity and occlusion in dense bubble fields. Using vortex rings in the swimming pool, we provide a proof of principle of the method. It is further illustrated by the vorticity field produced by a human swimmer. Graphic abstract: [Figure not available: see fulltext.].</p