1,416 research outputs found

    Children's literature in Latin America: gender identity in the education

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    This essay explores the notion of gender identity as a dynamic process modelled by socio-cultural relationships, in the context of education in Latin America. The historical construction of schooling in recent decades is discussed through some documents of UNESCO. As an example of gender inequality within educational proposals, some texts from children’s literature will be analysed to highlight the gender stereotypes that still exist in the editorial industry today

    Fungal solid state fermentation on agro-industrial wastes for acid wastewater decolourization in a continuous flow packed-bed bioreactor

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    This study was aimed at developing a process of solid state fermentation (SSF) with the fungi Pleurotus ostreatus and Trametes versicolor on apple processing residues for wastewater decolorization. Both fungi were able to colonize apple residues without any addition of nutrients, material support or water. P. ostreatus produced the highest levels of laccases (up to 9 U g-1 of dry matter) and xylanases (up to 80 U g-1 of dry matter). A repeated batch decolorization experiment was set up with apple residues colonized by P. ostreatus, achieving 50% decolorization and 100% detoxification after 24 h, and, adding fresh wastewater every 24 h, a constant decolorization of 50% was measured for at least 1 month. A continuous decolorization experiment was set up by a packed-bed reactor based on colonized apple residues achieving a performance of 100 mg dye L-1 day-1 at a retention time of 50

    Statistical image processing for the detection of dermoscopic criteria

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    An image based system implementing a well-known diagnostic method is disclosed for the automatic detection of melanomas as support to clinicians. The software procedure is able to recognize automatically the skin lesion within the digital image, measure morphological and chromatic feature, carry out a suitable classification for the detection of structural dermoscopic criteria provided by the 7-Point Check List. Experimental results about the adoption of statistical techniques applied to the border detection, feature extraction and classification as well as the resulting diagnostic score are described with reference to a large image set. Copyright © 2011 by the International Measurement Confederation (IMEKO) All rights reserved

    Electrochemical and morphological layer-by-layer characterization of electrode interfaces during a label-free impedimetric immunosensor build-up: The case of ochratoxin A

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    Abstract In this paper, we provide an in-depth electrochemical characterization of a label-free impedimetric immunosensor for rapid detection of ochratoxin A. The sensor was based on a carbodiimide-mediated amide coupling reaction to immobilize a specific ochratoxin A antibody onto 4-mercaptobenzoic acid-modified commercial screen-printed gold electrode. Different variables affecting the performance of the developed sensor were optimized. Cyclic voltammetry and electrochemical impedance spectroscopy were used to analyse modifications of the interfacial properties occurring at each step of the biosensor assembly. The free electrode surface area, the diffusion coefficient, the peak-to-peak separation, the heterogeneous electron transfer constant, and charge transfer resistance have been calculated and compared. The decrease of charge transfer resistance values was linearly proportional to the ochratoxin A concentration in the range of 0.37– 2.86 ng/mL, with a detection limit of 0.19 ng/mL, a limit of quantification of 0.40 ng/mL, very good selectivity, reproducibility, and storage stability in the absence of antifouling agents. Surface morphology and topographic data at each step of the immunosensor assembly were studied by Atomic Force Microscopy, which also provided information on the specific binding of ochratoxin A. Finally, contact angle measurements revealed the hydrophilicity evolution of the surface during sensor assembly enabling OTA binding

    Mutual learning exercise on citizen science initiatives: policy and practice. Fifth thematic report: scaling up citizen science

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    This publication addresses meanings, dimensions, models and approaches/strategies of scalability in citizen science as well as drivers, success factors and challenges of (up)scaling citizen science projects and initiatives across Europe. It provides a multi-dimension qualitative definition of scaling up, the MLE CSI-PP Responsible and Inclusive Scalability Framework, and eight key areas of action for policymakers aimed at supporting the (up)scaling of citizen science projects and initiatives across Europe. Ultimately it argues that (up)scaling should be a responsible and inclusive process, context- and domain-dependent, aligned with the logics of the projects/initiatives, driven by common scientific questions and common social challenges, and built on proven impact, related to science and scientific literacy, inclusion, regulatory frameworks, and matters of concern (e.g., environmental, societal)

    Statistical techniques applied to the automatic diagnosis of dermoscopic images

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    An image based system implementing a well‐known diagnostic method is disclosed for the automatic detection of melanomas as support to clinicians. The software procedure is able to recognize automatically the skin lesion within the digital image, measure morphological and chromatic parameters, carry out a suitable classification for the detection of structural dermoscopic criteria provided by the 7‐Point Check. Original contribution is referred to advanced statistical techniques, which are introduced at different stages of the image processing, including the border detection, the extraction of low‐level features and scoring of high order features (namely dermoscopic criteria). The proposed approach is experimentally tested with reference to a large image set of pigmented lesions

    Paraburkholderia sabiae Uses One Type VI Secretion System (T6SS-1) as a Powerful Weapon against Notorious Plant Pathogens

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    Paraburkholderia sabiae LMG24235 is a nitrogen-fixing betaproteobacterium originally isolated from a root nodule of Mimosa caesalpiniifolia in Brazil. We show here that this strain effectively kills strains from several bacterial families (Burkholderiaceae, Pseudomonadaceae, Enterobacteriaceae) which include important plant pathogens in a contact-dependent manner. De novo assembly of the first complete genome of P. sabiae using long sequencing reads and subsequent annotation revealed two gene clusters predicted to encode type VI secretion systems (T6SS), which we named T6SS-1 and T6SS-3 according to previous classification methods (G. Shalom, J. G. Shaw, and M. S. Thomas, Microbiology, 153:2689-2699, 2007, https://doi.org/10.1099/mic.0.2007/006585-0). We created P. sabiae with mutations in each of the two T6SS gene clusters that abrogated their function, and the T6SS-1 mutant was no longer able to outcompete other strains in a contact-dependent manner. Notably, our analysis revealed that T6SS-1 is essential for competition against several important plant pathogens in vitro, including Burkholderia plantarii, Ralstonia solanacearum, Pseudomonas syringae, and Pectobacterium carotovorum. The 9-log reduction in P. syringae cells in the presence of P. sabiae was particularly remarkable. Importantly, in an in vivo assay, P. sabiae was able to protect potato tubers from bacterial soft rot disease caused by P. carotovorum, and this protection was partly dependent on T6SS-1. IMPORTANCE Rhizobia often display additional beneficial traits such as the production of plant hormones and the acquisition of limited essential nutrients that improve plant growth and enhance plant yields. Here, we show that the rhizobial strain P. sabiae antagonizes important phytopathogens such as P. carotovorum, P. syringae, and R. solanacearum and that this effect is due to contact-dependent killing mediated by one of two T6SS systems identified in the complete, de novo assembled genome sequence of P. sabiae. Importantly, co-inoculation of Solanum tuberosum tubers with P. sabiae also resulted in a drastic reduction of soft rot caused by P. carotovorum in an in vivo model system. This result highlights the protective potential of P. sabiae against important bacterial plant diseases, which makes it a valuable candidate for application as a biocontrol agent. It also emphasizes the particular potential of rhizobial inoculants that combine several beneficial effects such as plant growth promotion and biocontrol for sustainable agriculture

    Re-scheduling in railways: the rolling stock balancing problem

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    This paper addresses the Rolling Stock Balancing Problem (RSBP). This problem arises at a passenger railway operator when the rolling stock has to be re-scheduled due to changing circumstances. These problems arise both in the planning process and during operations. The RSBP has as input a timetable and a rolling stock schedule where the allocation of the rolling stock among the stations does not fit to the allocation before and after the planning period. The problem is then to correct these off-balances, leading to a modified schedule that can be implemented in practice. For practical usage of solution approaches for the RSBP, it is important to solve the problem quickly. Therefore, the focus is on heuristic approaches. In this paper, we describe two heuristics and compare them with each other on some (variants of) real-life instances of NS, the main Dutch passenger railway operator. Finally, to get some insight in the quality of the proposed heuristics, we also compare their outcomes with optimal solutions obtained by solving existing rolling stock circulation models

    Determination of surface lattice strain in ZnTe epilayers on {100}GaAs by ion channeling and reflectance spectroscopy

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    We report on the direct measurements of surface lattice strain in ZnTe epitaxial layers on {100}GaAs substrates by ion channeling Rutherford backscattering spectrometry and low‐temperature (10 K) reflectance spectroscopy measurements. The measured ZnTe strain is the superposition of the expected thermal (tensile) strain and a thickness‐dependent residual compressive strain. Our data indicate that the removal of this residual strain is slower than the rate predicted by the equilibrium theory, following an apparent h−1/2 power‐law dependence on the epilayer thickness h, above ∌100 nm

    Mutual learning exercise on citizen science initiatives: policy and practice: final report

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    Over the past decade, great advances have been made in applying innovative participatory and inclusive research practices across a wide range of domains. These have involved increasing numbers of citizens in monitoring, observing, and co-researching societal issues such as climate change impacts on the environment and public health, sustainable mobility, and plastic pollution in rivers and oceans. Important outcomes have been achieved, from fundamental scientific discoveries1 to data that support evidence-informed policy
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