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GH3 Auxin-Amido Synthetases Alter the Ratio of Indole-3-Acetic Acid and Phenylacetic Acid in Arabidopsis
No full textAuxin is the first discovered plant hormone and is essential for many aspects of plant growth and development. Indole-3-acetic acid (IAA) is the main auxin and plays pivotal roles in intercellular communication through polar auxin transport. Phenylacetic acid (PAA) is another natural auxin that does not show polar movement. Although a wide range of species have been shown to produce PAA, its biosynthesis, inactivation and physiological significance in plants are largely unknown. In this study, we demonstrate that overexpression of the CYP79A2 gene, which is involved in benzylglucosinolate synthesis, remarkably increased the levels of PAA and enhanced lateral root formation in Arabidopsis. This coincided with a significant reduction in the levels of IAA. The results from auxin metabolite quantification suggest that the PAA-dependent induction of GRETCHEN HAGEN 3 (GH3) genes, which encode auxin-amido synthetases, promote the inactivation of IAA. Similarly, an increase in IAA synthesis, via the indole-3-acetaldoxime pathway, significantly reduced the levels of PAA. The same adjustment of IAA and PAA levels was also observed by applying each auxin to wild-type plants. These results show that GH3 auxin-amido synthetases can alter the ratio of IAA and PAA in plant growth and development.</p
Conservation basic income : A non-market mechanism to support convivial conservation
No full textThis article advances a proposal for conservation basic income (CBI) as a novel strategy for funding biodiversity conservation that moves beyond widely promoted market-based instruments (MBIs). This CBI proposal responds to two important empirical developments. The first concerns growing discussions around cash transfer programs (CTPs) and universal basic income (UBI). These are increasingly implemented or piloted yet do not usually take into account environmental issues including biodiversity conservation. The second relates to MBIs like payments for ecosystem services (PES) and REDD+ (reduced emissions through avoided deforestation and forest degradation). In practice, these programs have not only commonly failed to halt biodiversity loss and alleviate poverty but have also largely abandoned their market-based origins, leading to calls for moving beyond market-based conservation entirely. We conclude that the time is right to integrate and transcend these existing mechanisms to develop conservation basic income as part of a broader paradigm shift towards convivial conservation that foregrounds concerns for social justice and equity.</p
Incompatibility and phylogenetic relationship of I-complex plasmids
No full textPlasmid incompatibility is the inability of two plasmids to be stably maintained in one cell, resulting in loss of one of the plasmids in daughter cells. Dislodgement is a phenotypically distinct form of incompatibility, described as an imperfect reproduction, manifesting in rapid exclusion of a resident plasmid after superinfection. The relationship between plasmids of the phenotypic incompatibility groups IncB/O and IncZ is unclear. Their inability to co-exist was initially referred to as dislodgement while other research reached the conclusion that IncB/O and IncZ plasmids are incompatible. In this manuscript we re-evaluated the relationship between IncB/O and IncZ plasmids to settle these conflicting conclusions. We performed dislodgement testing of R16Δ (IncB/O) and pSFE-059 (IncZ) plasmids by electroporation in a bacterial cell and checked their stability. Stability tests of the obtained plasmid pair showed that the IncB/O plasmid was exclusively and almost completely lost from the heteroplasmid Escherichia coli population. Other IncB/O – IncZ pairs could not form a heteroplasmid population, using conjugation or electroporation. Our data supports the previous suggestion that IncB/O and IncZ plasmids may be considered phenotypically incompatible.</p
Improving the performance of polymer-flooding produced water electrodialysis through the application of pulsed electric field
No full textConcentration polarization and fouling hamper the desalination of polymer-flooding produced water (PFPW) via electrodialysis (ED). This water is an abundant by-product from the oil and gas industry. A common technique to mitigate both problems is the application of pulsed electric field (PEF), which consists in supplying a constant current during a short time (pulse) followed by a time without current (pause). Accordingly, this work evaluated the application of PEF during the ED of PFPW to improve the process performance and to reduce fouling incidences. The experimental work consisted in performing ED batch runs in a laboratory-scale stack containing commercial ion exchange membranes. Synthetic PFPW was desalinated under different operating regimes until a fixed number of charges were passed. After each experiment, a membrane pair was recovered from the stack and analyzed through diverse techniques. The application of PEF improved the ED performance in terms of demineralization percentage and energy consumption, the latter having reductions of 36% compared to the continuous mode. In general, the shorter the pulses, the higher the demineralization rate and the lower the energy consumption. Regarding the application of different pause lengths, longer pauses yielded lower energy consumptions, but also lower demineralization. Amorphous precipitates composed of polymer and calcium fouled most on the anion and cation exchange membranes, independently of the applied current regime, but in a moderate amount. Finally, the present study relates the observed effects of PEF application to the electrophoresis and diffusion of HPAM, and shows that PEF is a sound option to enhance the desalination of PFPW.</p
Effects of guanotrophication and warming on the abundance of green algae, cyanobacteria and microcystins in Lake Lesser Prespa, Greece
No full textLake Lesser Prespa in Greece is a vital breeding habitat for the Dalmatian and Great White Pelican and a shelter for numerous rare and endemic species. However, eutrophication processes are distressing the lake system and the outbreaks of cyanobacterial blooms during the warm months may pose a threat to aquatic organisms due to the presence of microcystins (MCs). In this study we hypothesize that nutrients (eutrophication), nutrient-rich pelican droppings (guanotrophication) and warming (climate change) can affect the algal growth and MCs production in the water layer of Lake Lesser Prespa. Seston collected from three lake sites was incubated at ambient (20°C) and high (30°C) temperature with or without the addition of nutrients (nitrogen (N), phosphorus (P)), or pelican droppings. Results showed increased chlorophyll-a at higher temperature (30°C). N addition yielded higher chlorophyll-a levels than the non-treated water or when only P was added. The addition of both N and P as well as the addition of pelican dropping resulted in the highest chlorophyll-a at both temperatures. Notably, in the dropping-treatments, cyanobacteria and MCs were promoted while changes were evoked in the relative contribution of toxic MC-variants. Guanotrophication may thus influence the cyanobacterial dynamics and most likely their toxicity profile at Lesser Prespa.</p
Pasteurized Akkermansia muciniphila increases whole-body energy expenditure and fecal energy excretion in diet-induced obese mice
No full textAccumulating evidence points to Akkermansia muciniphila as a novel candidate to prevent or treat obesity-related metabolic disorders. We recently observed, in mice and in humans, that pasteurization of A. muciniphila increases its beneficial effects on metabolism. However, it is currently unknown if the observed beneficial effects on body weight and fat mass gain are due to specific changes in energy expenditure. Therefore, we investigated the effects of pasteurized A. muciniphila on whole-body energy metabolism during high-fat diet feeding by using metabolic chambers. We confirmed that daily oral administration of pasteurized A. muciniphila alleviated diet-induced obesity and decreased food energy efficiency. We found that this effect was associated with an increase in energy expenditure and spontaneous physical activity. Strikingly, we discovered that energy expenditure was enhanced independently from changes in markers of thermogenesis or beiging of the white adipose tissue. However, we found in brown and white adipose tissues that perilipin2, a factor associated with lipid droplet and known to be altered in obesity, was decreased in expression by pasteurized A. muciniphila. Finally, we observed that treatment with pasteurized A. muciniphila increased energy excretion in the feces. Interestingly, we demonstrated that this effect was not due to the modulation of intestinal lipid absorption or chylomicron synthesis but likely involved a reduction of carbohydrates absorption and enhanced intestinal epithelial turnover. In conclusion, this study further dissects the mechanisms by which pasteurized A. muciniphila reduces body weight and fat mass gain. These data also further support the impact of targeting the gut microbiota by using specific bacteria to control whole-body energy metabolism.</p
Review : Synergy between mechanistic modelling and data-driven models for modern animal production systems in the era of big data
No full textMechanistic models (MMs) have served as causal pathway analysis and 'decision-support' tools within animal production systems for decades. Such models quantitatively define how a biological system works based on causal relationships and use that cumulative biological knowledge to generate predictions and recommendations (in practice) and generate/evaluate hypotheses (in research). Their limitations revolve around obtaining sufficiently accurate inputs, user training and accuracy/precision of predictions on-farm. The new wave in digitalization technologies may negate some of these challenges. New data-driven (DD) modelling methods such as machine learning (ML) and deep learning (DL) examine patterns in data to produce accurate predictions (forecasting, classification of animals, etc.). The deluge of sensor data and new self-learning modelling techniques may address some of the limitations of traditional MM approaches - access to input data (e.g. sensors) and on-farm calibration. However, most of these new methods lack transparency in the reasoning behind predictions, in contrast to MM that have historically been used to translate knowledge into wisdom. The objective of this paper is to propose means to hybridize these two seemingly divergent methodologies to advance the models we use in animal production systems and support movement towards truly knowledge-based precision agriculture. In order to identify potential niches for models in animal production of the future, a cross-species (dairy, swine and poultry) examination of the current state of the art in MM and new DD methodologies (ML, DL analytics) is undertaken. We hypothesize that there are several ways via which synergy may be achieved to advance both our predictive capabilities and system understanding, being: (1) building and utilizing data streams (e.g. intake, rumination behaviour, rumen sensors, activity sensors, environmental sensors, cameras and near IR) to apply MM in real-time and/or with new resolution and capabilities; (2) hybridization of MM and DD approaches where, for example, a ML framework is augmented by MM-generated parameters or predicted outcomes and (3) hybridization of the MM and DD approaches, where biological bounds are placed on parameters within a MM framework, and the DD system parameterizes the MM for individual animals, farms or other such clusters of data. As animal systems modellers, we should expand our toolbox to explore new DD approaches and big data to find opportunities to increase understanding of biological systems, find new patterns in data and move the field towards intelligent, knowledge-based precision agriculture systems.</p
Stedelijk groen helpt tegen klimaatverandering
No full textIn het klimaatakkoord is de rol die stedelijk groen kan spelen voor de klimaatopgave onderbelicht. Dat is jammer, omdat de oppervlakte van steden, dorpen en infrastructuur in Nederland aanzienlijk is. En het aardige van stedelijk groen is dat dit naast het vastleggen van CO2, ook kan bijdragen aan aanpassing aan klimaatverandering: wateropvang bij piekbuien en verkoeling van de stad tijdens hittegolven
Natte kraamkamers: Uiterwaarden onmisbaar voor jonge vis
No full textVoor een gezonde visgemeenschap in laaglandrivieren zijn uiterwaarden, ook wel vloedvlakten genoemd, erg belangrijk. Daarom is sinds de jaren ’90 van de vorige eeuw in Nederland veel geïnvesteerd in het herstel van de ecologische kwaliteit van uiterwaarden en daarmee die van het hele riviersysteem
Understanding interactions and relationships in pest management innovation processes in Bangladesh
No full textThis thesis uses Agricultural Innovation System (AIS) perspective to understand the pest management innovation processes in Bangladesh where substantial investments in Integrated Pest Management (IPM) promotion by Farmer Field School (FFS) approach obtained little progress in achieving higher levels of IPM adoption. According to AIS perspective, pest management related innovations require interactional processes to make IPM knowledge and practices economically and practically viable which also require some socio-technical changes. The FFS approach and the AIS perspective both draw special attention to interactional processes like joint and need-based problem identification; interactive learning for problem solving; knowledge exchange; etc. This ethnographic research is designed to gain an in-depth understanding about how these interactional processes and relationships play a role in pest management innovation processes: networking, demand articulation and innovation management among farmers, government extension officers, pesticide companies’ promotional officers and pesticide traders at local context. This research also aims to decipher the cultural patterns, values and behaviour of relevant actors and organizations in order to understand how cultural diversities influence interactions and relationships in the innovation processes. Chapter 1 discusses the research background with a particular focus on pesticide (over)use trend in Bangladesh; the main theoretical concepts from the existing literature about innovation, its relevance to key concerns, prospects and challenges around pest management, pesticide use and IPM. The chapter introduces the research objectives, main theme of each empirical study, the specific research questions and the overall research methodology. The farmer level study in Chapter 2 focuses on cultural perspectives in two IPM-FFS trained farmer communities. The study aims to understand local interactions, pest management related knowledge sharing and learning dynamics to decipher the cultural patterns and their influence on these processes and IPM uptake in the two communities. Results reveal that certain cultural patterns in one community hamper processes of innovation where farmers rarely interacted or shared pest management knowledge and experiences, and continued to rely on pesticide based cultivation. However, the other community demonstrates strong group solidarity which facilitates innovation processes; the farmers shared pest management knowledge in a wide network, and started to apply some IPM practices while reducing pesticide use. Results also suggest that the level of education, poverty, seasonality, severity of pests, and the diversity of IPM-FFS implementation also influence pest management processes and different IPM uptake at different communities. Chapter 3 explores the role of ‘organizational culture’ of two agricultural extension offices in the implementation of IPM-FFSs in the two communities studied in Chapter 2. Results reveal that the cultural patterns of one office tend to follow a linear technology transfer approach while the other office tends to follow a relatively more farmer-oriented extension approach. The distinct cultural patterns of the offices are closely linked to the directors’ basic assumptions which influenced the actions of the field officers in the implementation of IPM-FFSs in the two communities. In one office, the director shows higher accountability to address farmers’ problem and the respective field officer implemented more interactive IPM-FFS in the community that showed higher group solidarity. However, both the cultural patterns of the farmer community and extension office together influence the implementation and outcome of IPM-FFS in different contexts. Chapter 4 uses the literature on Multiple Level Perspective (MLP) on transitions and concept of niche-regime interaction. This chapter focuses on strategies of networking; the alignments among interconnected actors, and institutions (local level business collaboration, incentive mechanisms, etc.) on two pesticide companies and one bio-pesticide company; and their influence on farmers’ pest management preferences for IPM or pesticides. The study reveals that, compared to the bio-pesticide company and government-run IPM-FFSs, the two pesticide companies invested heavily in networking and relationship building with farmers and traders to promote pesticide sale. Results find a substantial volume of pesticide sales in two IPM-FFS trained communities and nearby markets compared to a negligible sale of IPM products. Chapter 5 investigates distinct patterns of interaction between pesticide traders and farmers. The chapter describes how differentially these interaction patterns shape the extent to which traders influence farmers’ choices about pesticide selection and use. Results reveal that a considerably higher proportion of the farmers (45% or so) who visited pesticide shops completely depend on the traders’ pest management advice. Content analysis of traders’ advices shows a clear association with three types of risks: pesticide overuse, wrong pesticide use, and spraying a mixture of different pesticides without expert’s recommendation. These risks are also associated with, and reinforced by, the dominant credit relationships between pesticide companies, traders and farmers. The pesticide companies play the role of central knowledge providers to the traders who in turn promote pesticide based pest management practices to farmers. Chapter 6 provides the major findings of the research and an analytical discussion using the literature on multiple level perspective and dimensions that determine socio-technical transition processes. The discussions reveal prominent links between technology, knowledge, and culture dimensions; pesticide companies, market & user relation dimensions; and guiding principles and policy & regulation dimensions that explain comparative strength and weaknesses of pesticide regime and IPM niche in the present context of Bangladesh. The discussion concludes that the current position of IPM niche is too weak to compete with the dominant players in the pesticide regime to substantially reduce pesticide use. Frequent interactions between the farmers; traders and pesticide companies create a strong support network characterized by mutual relationships of interdependency which encourages pesticide sale. This support network further strengthens the position of pesticide regime when couple with weak policy regulations at local pesticide trade. The thesis provides some specific policy recommendations on: policy amendments and the enforcement of existing pesticide legislation to regulate the regime activity; formation of collaborative support network to nurture and strengthen the IPM niche; provision of more demand-led interactive advisory services by government’s extension department with special attention to understanding the cultural patterns of different farmer communities to adopt culturally sensitive education and advisory approach; and different types of IPM and teaching approaches to make sure their best use in the context of Bangladesh.