367 research outputs found

    Crotonaldehyde hydrogenation on Rh/TiO2 catalysts. In situ DRIFTS studies

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    The surface and catalytic properties in the vapor-phase hydrogenation of crotonaldehyde on Rh/TiO2 has been studied. It was found that a partial reduction of the support produces a surface decoration of the metal component. Thus, interfacial sites are created, which are responsible of an increase in the selectivity to crotyl alcohol, via enhancement of the polarization of the C=O bond. Photoelectron spectra revelead that rhodium is in different oxidation states, with a contribution of ca. 20 % Rhd + and 80 % Rhº species for LTR catalyst and only a slight increase of Rhd + for HTR catalyst. TEM studies revelead that Rh has metal particle size close 3 nm with small increases in the catalyst reduced at high temperature. DRIFTS essayed carried out under reaction conditions allowed to identify crotonaldehyde species strongly adsorbed through the C=C bond and weakly coordinated through both the C=C and C=O bonds. After reduction at 723 K an increase in the peak at 1660 cm-1 ascribed to an interaction between the carbonyl group and the surface, was observed. This peak seems to be stabilized at interfacial Rh/TiOx sites The deactivation in crotyl alcohol formation can be ascribed to the generation of strongly chemisorbed asymmetric carboxylate species detected by band at 1740 cm-1. This band grows at expense of crotonaldehyde O s - bonded intermediate chemisorbed on coordinatively unsaturated sites (Lewis acid sites) responsible of the crotyl alcohol obtaintion (detected by a band at 1653 cm-1). Additionally, a small band at 2068 cm-1 assigned to CO adsorbed on transition metals, which increases with time on-stream may explain the deactivation of the catalysts in flow systems

    Investigating the impact of UV-C/H2O2 and sunlight/H2O2 on the removal of antibiotics, antibiotic resistance determinants and toxicity present in urban wastewater

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    This work aimed at exploring the impact of UV-C/H2O2 and sunlight/H2O2 processes, applied at pilot scale, on removing: (i) ciprofloxacin and sulfamethoxazole, (ii) cultivable Escherichia coli and Pseudomonas aeruginosa grown in the presence and absence of sub-minimal inhibitory concentrations of ciprofloxacin and sulfamethoxazole and (iii) the genes 16S rRNA and selected antibiotic resistance genes (ARGs) (i.e., sul1, blaCTX-M, qnrS, tetM, etc.) from urban wastewater. The major antibiotic transformation products (TPs) formed, were elucidated and the chronic toxicity of the whole effluent mixture against Vibrio fischeri was evaluated. The capability of the processes, in terms of the elimination of the antibiotics present in urban wastewater, varied among the two light sources used: both antibiotics were fully removed during UV-C/Η2Ο2, whereas only ciprofloxacin was removed during the sunlight/H2O2. The photo-transformation of the antibiotics led to the identification of 21 and 18 TPs of ciprofloxacin and sulfamethoxazole, respectively, while all of them retained their core moiety, responsible for the antibacterial activity. All the UV-C/H2O2-treated samples were found to be toxic, whereas the luminescence of V. fischeri was not inhibited when tested in the sunlight/H2O2-treated samples. During both processes, E. coli, P. aeruginosa and the colonies of these species still viable in the presence of antibiotics, were successfully inactivated to values below the detection limit. However, sunlight/H2O2 has not achieved complete disinfection, as regrowth of E. coli and P. aeruginosa colonies was observed after 48 h of storage of the treated effluent. Finally, none of the technologies tested was able to completely remove the target ARGs, confirming their inability to prevent the spread of resistance determinants to the environment.info:eu-repo/semantics/acceptedVersio

    EuroFlow-based flowcytometric diagnostic screening and classification of primary immunodeficiencies of the lymphoid system

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    Guidelines for screening for primary immunodeficiencies (PID) are well-defined and several consensus diagnostic strategies have been proposed. These consensus proposals have only partially been implemented due to lack of standardization in laboratory procedures, particularly in flow cytometry. The main objectives of the EuroFlow Consortium were to innovate and thoroughly standardize the flowcytometric techniques and strategies for reliable and reproducible diagnosis and classification of PID of the lymphoid system. The proposed EuroFlow antibody panels comprise one orientation tube and seven classification tubes and corresponding databases of normal and PID samples. The 8-color 12-antibody PID Orientation tube (PIDOT) aims at identification and enumeration of the main lymphocyte and leukocyte subsets; this includes naive pre-germinal center (GC) and antigen-experienced post-GC memory B-cells and plasmablasts. The seven additional 8(-12)-color tubes can be used according to the EuroFlow PID algorithm in parallel or subsequently to the PIDOT for more detailed analysis of B-cell and T-cell subsets to further classify PID of the lymphoid system. The Pre-GC, Post-GC, and immunoglobulin heavy chain (IgH)-isotype B-cell tubes aim at identification and enumeration of B-cell subsets for evaluation of B-cell maturation blocks and specific defects in IgH-subclass production. The severe combined immunodeficiency (SCID) tube and T-cell memory/effector subset tube aim at identification and enumeration of T-cell subsets for assessment of T-cell defects, such as SCID. In case of suspicion of antibody deficiency, PIDOT is preferably directly combined with the IgH isotype tube(s) and in case of SCID suspicion (e.g., in newborn screening programs) the PIDOT is preferably directly combined with the SCID T-cell tube. The proposed >= 8-color antibody panels and corresponding reference databases combined with the EuroFlow PID algorithm are designed to provide fast, sensitive and cost-effective flowcytometric diagnosis of PID of the lymphoid system, easily applicable in multicenter diagnostic settings world-wide

    Human-carnivore relations: conflicts, tolerance and coexistence in the American West

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    Carnivore and humans live in proximity due to carnivore recovery efforts and ongoing human encroachment into carnivore habitats globally. The American West is a region that uniquely exemplifies these human-carnivore dynamics, however, it is unclear how the research community here integrates social and ecological factors to examine human-carnivore relations. Therefore, strategies promoting human-carnivore coexistence are urgently needed. We conducted a systematic review on human-carnivore relations in the American West covering studies between 2000 and 2018. We first characterized human-carnivore relations across states of the American West. Second, we analyzed similarities and dissimilarities across states in terms of coexistence, tolerance, number of ecosystem services and conflicts mentioned in literature. Third, we used Bayesian modeling to quantify the effect of social and ecological factors influencing the scientific interest on coexistence, tolerance, ecosystem services and conflicts. Results revealed some underlying biases in human-carnivore relations research. Colorado and Montana were the states where the highest proportion of studies were conducted with bears and wolves the most studied species. Non-lethal management was the most common strategy to mitigate conflicts. Overall, conflicts with carnivores were much more frequently mentioned than benefits. We found similarities among Arizona, California, Utah, and New Mexico according to how coexistence, tolerance, services and conflicts are addressed in literature. We identified percentage of federal/private land, carnivore family, social actors, and management actions, as factors explaining how coexistence, tolerance, conflicts and services are addressed in literature. We provide a roadmap to foster tolerance towards carnivores and successful coexistence strategies in the American West based on four main domains, (1) the dual role of carnivores as providers of both beneficial and detrimental contributions to people, (2) social-ecological factors underpinning the provision of beneficial and detrimental contributions, (3) the inclusion of diverse actors, and (4) cross-state collaborative management

    The EuroFlow PID orientation tube for flow cytometric diagnostic screening of primary immunodeficiencies of the lymphoid system

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    Copyright © 2019 van der Burg, Kalina, Perez-Andres, Vlkova, Lopez-Granados, Blanco, Bonroy, Sousa, Kienzler, Wentink, Mejstríková, Šinkorova, Stuchly, van Zelm, Orfao and van Dongen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.In the rapidly evolving field of primary immunodeficiencies (PID), the EuroFlow consortium decided to develop a PID orientation and screening tube that facilitates fast, standardized, and validated immunophenotypic diagnosis of lymphoid PID, and allows full exchange of data between centers. Our aim was to develop a tool that would be universal for all lymphoid PIDs and offer high sensitivity to identify a lymphoid PID (without a need for specificity to diagnose particular PID) and to guide and prioritize further diagnostic modalities and clinical management. The tube composition has been defined in a stepwise manner through several cycles of design-testing-evaluation-redesign in a multicenter setting. Equally important appeared to be the standardized pre-analytical procedures (sample preparation and instrument setup), analytical procedures (immunostaining and data acquisition), the software analysis (a multidimensional view based on a reference database in Infinicyt software), and data interpretation. This standardized EuroFlow concept has been tested on 250 healthy controls and 99 PID patients with defined genetic defects. In addition, an application of new EuroFlow software tools with multidimensional pattern recognition was designed with inclusion of maturation pathways in multidimensional patterns (APS plots). The major advantage of the EuroFlow approach is that data can be fully exchanged between different laboratories in any country of the world, which is especially of interest for the PID field, with generally low numbers of cases per center.The coordination and innovation processes of this study were supported by the EuroFlow Consortium (Chairmen: MvdB and AO). MvZ is supported by Senior Research Fellowship GNT1117687 from the Australian National Health and Medical Research Council. TK and EM were supported by projects 15-28541A from Ministry of Health, LO1604 from Ministry of Education, Youth and Sports and GBP302/12/G101 from Grant Agency of the Czech Republic. MP-A, EB, and AO were supported by a grant from the Junta de Castilla y León (Fondo Social Europeo, ORDEN EDU/346/2013, Valladolid, Spain) and the CB16/12/00400 grant (CIBER/ONC, Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, - Madrid, Spain- and FONDOS FEDER), the FIS PI12/00905-FEDER grant (Fondo de Investigación Sanitaria of Instituto de Salud Carlos III, Madrid, Spain) and AP119882013 grant (Fundación Mutua Madrileña, Madrid, Spain). Publishing costs for this article were covered by the International Union of Immunological Societies (IUIS).info:eu-repo/semantics/publishedVersio

    Selecting patterns and features for between- and within-crop-row weed mapping using UAV-imagery

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    This paper approaches the problem of weed mapping for precision agriculture, using imagery provided by Unmanned Aerial Vehicles (UAVs) from sunflower and maize crops. Precision agriculture referred to weed control is mainly based on the design of early post-emergence site-specific control treatments according to weed coverage, where one of the most important challenges is the spectral similarity of crop and weed pixels in early growth stages. Our work tackles this problem in the context of object-based image analysis (OBIA) by means of supervised machine learning methods combined with pattern and feature selection techniques, devising a strategy for alleviating the user intervention in the system while not compromising the accuracy. This work firstly proposes a method for choosing a set of training patterns via clustering techniques so as to consider a representative set of the whole field data spectrum for the classification method. Furthermore, a feature selection method is used to obtain the best discriminating features from a set of several statistics and measures of different nature. Results from this research show that the proposed method for pattern selection is suitable and leads to the construction of robust sets of data. The exploitation of different statistical, spatial and texture metrics represents a new avenue with huge potential for between and within crop-row weed mapping via UAV-imagery and shows good synergy when complemented with OBIA. Finally, there are some measures (specially those linked to vegetation indexes) that are of great influence for weed mapping in both sunflower and maize crops

    Removal of nutrients and pesticides from agricultural runoff using microalgae and cyanobacteria

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    The use of pesticides in agriculture has ensured the production of different crops. However, pesticides have become an emerging public health problem for Latin American countries due to their excessive use, inadequate application, toxic characteristics, and minimal residue control. The current project evaluates the ability of two strains of algae (Chlorella and Scenedesmus sp.) and one cyanobacteria (Hapalosyphon sp.) to remove excess pesticides and other nutrients present in runoff water from rice production. Different concentrations of wastewater and carbon sources (Na2CO3 and NaHCO3 ) were evaluated. According to the results, all three strains can be grown in wastewater without dilution (100%), with a biomass concentration comparable to a synthetic medium. All three strains significantly reduced the concentration of NO3 and PO4 (95 and 85%, respectively), with no difference between Na2CO3 or NaHCO3 . Finally, Chlorella sp. obtained the highest removal efficiency of the pesticide (Chlorpyrifos), followed by Scenedesmus and Hapalosyphon sp. (100, 75, and 50%, respectively). This work shows that it is possible to use this type of waste as an alternative source of nutrients to obtain biomass and metabolites of interest, such as lipids and carbohydrates, to produce biofuels

    Sarcoptic mange in wild ruminants in Spain: solving the epidemiological enigma using microsatellite markers

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    Background: In Spain, sarcoptic mange was first described in native wildlife in 1987 in Cazorla Natural Park, causing the death of nearly 95% of the local native population of Iberian ibex (Capra pyrenaica). Since then, additional outbreaks have been identified in several populations of ibex and other wild ungulate species throughout the country. Although the first epizootic outbreak in wildlife was attributed to the introduction of an infected herd of domestic goats, the origin and the cause of its persistence remain unclear. The main aims of this study are to understand (i) the number of Sarcoptes scabiei “strains” circulating in wild ruminant populations in Spain, and (ii) the molecular epidemiological relationships between S. scabiei and its hosts. Methods: Ten Sarcoptes microsatellite markers were used to characterize the genetic structure of 266 mites obtained from skin scrapings of 121 mangy wild ruminants between 2011 and 2019 from 11 areas in Spain. Results: Seventy-three different alleles and 37 private alleles were detected. The results of this study show the existence of three genetic strains of S. scabiei in the wild ruminant populations investigated. While two genetic clusters of S. scabiei were host- and geography-related, one cluster included multi-host mites deriving from geographically distant populations. Conclusions: The molecular epidemiological study of S. scabiei in wild ruminants in Spain indicates that the spreading and persistence of the parasite may be conditioned by host species community composition and the permissiveness of each host population/community to the circulation of individual “strains,” among other factors. Wildlife–livestock interactions and the role of human-driven introduction or trade of wild and domestic animals should be better investigated to prevent further spread of sarcoptic mange in as yet unaffected natural areas of the Iberian Peninsula
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