Plants adapt to soil injury and biotic stress via cell regeneration. In Arabidopsis, root tip damage by genotoxic agents, antibiotics, UV light and cutting induces a program that recovers the missing ...tissues through activation of stem cells and involves ethylene response factor 115 (ERF115), which triggers cell replenishment. Here, we show that mutation of the gene encoding an MED18 subunit of the transcriptional MEDIATOR complex and chromate Cr(VI), an environmental pollutant, synergistically trigger a developmental program that enables the splitting of the meristem in vivo to produce twin roots. Expression of the quiescent centre gene marker WOX5, auxin‐inducible DR5:GFP reporter and the ERF115 factor traced the changes in cell identity during the conversion of single primary root meristems into twin roots and were induced in an MED18 and chromate‐dependent manner during the root twinning events, which also required auxin redistribution and signalling mediated by IAA14/SOLITARY ROOT (SLR1). Splitting of the root meristem allowed dichotomous root branching in Arabidopsis, a poorly understood process in which stem cells may act to enable whole organ regeneration.
This manuscript describes the twinning of the primary root meristem, also termed root fasciation, in Arabidopsis med18 mutants treated with chromate. Root regeneration takes place through cell re‐specification programs, which correlates with quiescent centre, auxin re‐distribution and cell renewal.
The aim of this review is to show the evolution of the dairy goat sector in Europe from all perspectives. Starting from the current situation, the challenges and future potential of this livestock ...system are presented, as well as strategies to overcome the difficulties faced. Europe holds 1.9% of the world goat population and produces 15.1% of goat milk recorded worldwide. The goat species plays a fundamental economic, social and environmental role in many regions of Europe. The wide diversity of production systems and autochthonous breeds makes the sector very heterogeneous. In order to improve viability, a number of strategies need to be adopted to solve the current problems such as a low profitability, absence of generational change and a little or no recognition of the social and environmental role of the sector. Some strategies to improve the situation of the European goat sector include: i) generating market value that will recognise the diversity of the dairy goat sector (breeds, feeding models, derived products…); ii) promoting and raising awareness of the functional attributes of goat milk and derived products so as to increase consumption; iii) assigning an economic value to environmental and social functions; iv) improving working conditions through technological innovation to make goat farming more attractive to young people; and v) processing more milk into cheese or other dairy products in production areas.
Studies of plant-pathogen interactions have historically focused on simple models of infection involving single host-single disease systems. However, plant infections often involve multiple species ...and/or genotypes and exhibit complexities not captured in single host-single disease systems. Here, we review recent insights into co-infection systems focusing on the dynamics of host-multi-pathogen interactions and the implications for host susceptibility/resistance. In co-infection systems, pathogen interactions include: (i) Competition, in which competing pathogens develop physical barriers or utilize toxins to exclude competitors from resource-dense niches; (ii) Cooperation, whereby pathogens beneficially interact, by providing mutual biochemical signals essential for pathogenesis, or through functional complementation via the exchange of resources necessary for survival; (iii) Coexistence, whereby pathogens can stably coexist through niche specialization. Furthermore, hosts are also able to, actively or passively, modulate niche competition through defense responses that target at least one pathogen. Typically, however, virulent pathogens subvert host defenses to facilitate infection, and responses elicited by one pathogen may be modified in the presence of another pathogen. Evidence also exists, albeit rare, of pathogens incorporating foreign genes that broaden niche adaptation and improve virulence. Throughout this review, we draw upon examples of co-infection systems from a range of pathogen types and identify outstanding questions for future innovation in disease control strategies.
Purpose - The purpose of this paper is to analyze the current state of the art and trends with regard to business process measurement by means of a systematic review of literature.Design methodology ...approach - The results are obtained through a systematic review carried out according to existing relevant guidelines. Additionally, a specific methodology through which to systematically obtain all the most important journals is followed. In total, 19 relevant articles are selected and later analyzed. A subsequent critical analysis of the data obtained is applied to identify the gaps in the current literature.Findings - A considerable effort has been made by researchers in the field of business process measurement, particularly in recent years. Many of the defined measures for business processes have been applied to models (approximately 77 per cent). Most of the initiatives concerning business measurement have been adapted from the software engineering field. A small percentage of the existing business process measures has been empirically validated.Originality value - The results presented contribute towards providing an updated overview of the current state of research into business process measurement, in order to identify existing research gaps and concerns on which ongoing and future research efforts on this topic can be focused.
SHOPPER Ruiz, Francisco J. R.; Athey, Susan; Blei, David M.
The annals of applied statistics,
03/2020, Letnik:
14, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We develop SHOPPER, a sequential probabilistic model of shopping data. SHOPPER uses interpretable components to model the forces that drive how a customer chooses products; in particular, we designed ...SHOPPER to capture how items interact with other items. We develop an efficient posterior inference algorithm to estimate these forces from large-scale data, and we analyze a large dataset from a major chain grocery store. We are interested in answering counterfactual queries about changes in prices. We found that SHOPPER provides accurate predictions even under price interventions, and that it helps identify complementary and substitutable pairs of products.
We aim to understand the factors that drive citizens of different countries to adhere to recommended self-protective behaviors during the COVID-19 pandemic.
Survey data was obtained through the ...COVID-19 Impact project. We selected countries that presented a sufficiently complete time series and a statistically relevant sample for running the analysis: Cyprus, Germany, Greece, Ireland, Latvia, Spain, Switzerland, the United Kingdom, and the United States of America. To identify country-specific differences in self-protective behaviors, we used previous evidence and change-point detection analysis to establish variations across participating countries whose effect was then assessed by means of interrupted series analysis.
A high level of compliance with health and governmental authorities' recommendations were generally observed in all included countries. The level of stress decreased near the period when countries such as Cyprus, Greece or the United Kingdom relaxed their prevention behavior recommendations. However, this relaxation of behaviors did not occur in countries such as Germany, Ireland, or the United States. As observed in the change-point detection analysis, when the daily number of recorded COVID-19 cases decreased, people relaxed their protective behaviors (Cyprus, Greece, Ireland), although the opposite trend was observed in Switzerland.
COVID-19 self-protective behaviors were heterogeneous across countries examined. Our findings show that there is probably no single winning strategy for exiting future health crises, as similar interventions, aimed to promote self-protective behaviors, may be received differently depending on the specific population groups and on the particular geographical context in which they are implemented.
This paper shows the direct comparison of 4 different catalysts (homogenous alkaline (KOH), heterogeneous alkaline (CaO), homogenous acid (H2SO4) and a new biocatalyst (lipase from Thermomyces ...lanuginosus (TLL) immobilized on octadecyl methacylate)) in the production of biodiesel from cooking oils. The reactions for each catalyst were optimized using response surface statistical methodology, considering as main parameters: substrates molar ratio, percentage of catalyst and reaction time, whereas for enzymatic catalysis instead reaction time, we studied water concentration. Alkaline homogenous catalysis was found to be the most effective, as expected from literature. However, for first time, the new biocatalyst from TLL is just around one order of magnitude under the homogenous catalysis in reaction rate and surpassed the heterogeneous catalysis or the acid catalysis (similar yields in 2 h versus the 1 h of the alkaline catalyst). Moreover, the reaction product using the biocatalytic approach was much cleaner and less energy demanding than the other catalytic approaches. From our view, this is the first report where biocatalysis is close to conventional catalysis in the production of biodiesel.
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•Production of biodiesel using used cooking oil has been studied using alkaline, acid and enzymatic catalysis.•Each strategy has been optimized by using response surface methodology approach.•The good performance of the new TLL biocatalyst made it the second most efficient.•Alkaline catalyst is the most effective, but the gap with biocatalysis is becoming smaller.
This paper addresses the mapping problem. Using a conjugate prior form, we derive the exact theoretical batch multiobject posterior density of the map given a set of measurements. The landmarks in ...the map are modeled as extended objects, and the measurements are described as a Poisson process, conditioned on the map. We use a Poisson process prior on the map and prove that the posterior distribution is a hybrid Poisson, multi-Bernoulli mixture distribution. We devise a Gibbs sampling algorithm to sample from the batch multiobject posterior. The proposed method can handle uncertainties in the data associations and the cardinality of the set of landmarks, and is parallelizable, making it suitable for large-scale problems. The performance of the proposed method is evaluated on synthetic data and is shown to outperform a state-of-the-art method.
The exploration of alternatives to the use of chemical preservatives in food is a topic that has attracted great attention. The implementation of regulations associated with the reduction of these ...elements directly affects the production of cured meat products, with the premise of looking for more “natural” alternatives. From a previously identified collection of 24 strains of Debaryomyces hansenii, isolated from dry meat products of the “Valle de los Pedroches” (Córdoba), a screening was carried out to determine which strains had inhibitory potential against a battery of fungi belonging to the genera Aspergillus, Penicillium, and Candida. After a series of general trials, four strains showing the greatest potential were selected by a streak inhibition assay performed at several concentrations of NaCl. The inhibitory activity of the selected D. hansenii strains was later evaluated by measuring their fungal antagonistic diffusible and volatile compound production following radial inhibition and mouth-to-mouth approaches, respectively. Growth aspects, sporulation, and morphology changes were also considered during these assays. The results support ideas already raised in previous studies, such as the presence of D. hanseniii could imply a reduction of pathogenic fungi in food. Autochthonous yeast strains inhibited not only the mycelial growth, but also sporulation, which strengthens the biocontrol activity of this yeast. Our results show that, under certain conditions, all tested D. hansenii strains were able to alter the growth/development of fungi, being especially evident in the cases of Penicillium expansum and Aspergillus niger. Finally, our research can facilitate the future comparison of results in this area, since we contributed to standardize the methodology described to date, we quantified the number of yeast cells and spores used during the experiments, we homogenized growth conditions for both, yeasts, and molds, and applied an image analyzer software to quantify the growth of the studied microorganisms in solid media.
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