88 research outputs found

    Removal Of Cyanobacteria Toxins From Drinking Water By Adsorption On Activated Carbon Fibers

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    Natural fibers from macadamia nut shell, dried coconut shell endocarp, unripe coconut mesocarp, sugarcane bagasse and pine wood residue were used to prepare activated carbon fibers (ACF) with potential application for removing microcystins. The ACF from pine wood and sugar cane bagasse were used to remove [D-Leucine1 MCYST-LR from water. After 10 minutes of contact time, more than 98% of toxin was removed by the ACF. The microcystin adsorption monolayer, qm, in the ACF recovered 200 and 161 μg.mg-1, with the Langmuir adsorption constant, KL, of 2.33 and 1.23 L.mg-1. Adsorption of [D-Leucine1]MCYST-LR in continuous process was studied for a fixed-bed ACF prepared from coconut shell and sugar cane bagasse and for two commercial activated carbon samples from treatment water plants of two Brazilian hemodialysis centers. Saturation of the beds occurred after 80 to 320 minutes, and the adsorption capacity for that toxin varied from 4.11 to 12.82 μg.mg-1.113371380Honda RY, Mercante CTJ, Vieira JMS, Esteves KE, Cabianca MAA, Azevedo MTP. Cianotoxinas em pesqueiros da região metropolitana de São Paulo. In: Esteves KE, Sant'Anna CL. (Org.). Pesqueiros sob uma visão integrada de meio ambiente, saúde pública e manejo. São Carlos: Rima2006. p. 105-120Sant'anna, C.L., Azevedo, M.T.D., Contribution to the knowledge of potentially toxic Cyanobacteria from Brazil (2000) Nova Hedwigia, 71 (3-4), pp. 359-385Landsberg, J.H., The effects of harmful algal blooms on aquatic organisms (2002) Reviews in Fisheries Science, 10 (2), pp. 113-390Hoffman, J.R.H., Removal of Microcystis toxins in water purification process (1976) Water S.A, 2 (2), pp. 58-60Keijola, A.M., Himberg, K., Esala, A.L., Sivonen, K., Hiisvirta, L., Removal of cyanobacterial toxins in water-treatment processes - laboratory and pilot-scale experiments (1988) Toxicity Assessment, 3 (5), pp. 643-656Falconer, I.R., Runnegar, M.T.C., Buckley, T., Huyn, V.L., Bradshaw, P., Use of powdered and granular activated carbon to remove toxicity from drinking water containing cyanobacterial toxins (1989) Journal American Water Works Association, 18 (2), pp. 102-105Himberg, K., Keijola, A.M., Hiisvirta, L., Pyysalo, H., Sivonen, K., The effect of water treatment processes on the removal of hepatotoxins from Microcystis and Oscillatoria cyanobacteria: A laboratory study (1988) Water Research, 23 (8), pp. 979-984Ministério do Desenvolvimento, Indústria e Comércio Exterior do Brasil (2005) Importation and exportation of activated carbon from Brazil, , http://aliceweb.desenvolvimento.gov.br, BRASIL, Available from:, Accessed on: JanuaryMatthiensen, A., Beattie, K.A., Yunes, J.S., Kaya, K., Codd, G.A., D-Leu(1) microcystin-LR, from the cyanobacterium Microcystis RST 9501 and from a Microcystis bloom in the Patos Lagoon estuary, Brazil (2000) Phytochemistry, 55 (5), pp. 383-387Oliveira, A.C.R., Magalhães, S.V.F., Soares, R.M., Azevedo, S.M.F.O., Influence of drinking water composition on quantitation and biological activity of dissolved microcystin (Cyanotoxin) (2005) Environmental toxicology, 20 (2), pp. 126-130Albuquerque-Jr, E.C., Mendez, M.O., Coutinho, A.R., Franco, T.T., Production and characterization of activated carbon from Brazilian agricultural residues (2005) Proceedings of the third Brazilian Carbono Congress, pp. 401-410. , Castro AT ed, November 7-11Rio de Janeiro, Brazil. Rio de Janeiro: Department of Science and Thecnology and Thecnological Center of the Brazilian Army;Webb, P.A., Orr, C., Surface area and pore structure by gas adsorption (1997) Analytical methods in fine particle technology, , Atlanta: Micromeritics Instrument Corp. Atlanta;, 301 pKuroda EK, Albuquerque-Jr EC, Di Bernardo L, Trofino JC. Caracteriza&ão e escolha do tipo de carvão ativado a ser empregado no tratamento de aguas contendo microcistinas. In: Brazilian Association of Sanitation and Environmental Engineering (ed.). Brazilian Environmental Sanitation: utopia or reality? Proceedings of the twentieth third Brazilian Congrees of Sanitary and Environmental Engineering2005 18-23Mato Grosso, Brazil. Campo Grande: Brazilian Association of Sanitary and Environmental Engineering2005. p. 1-10Albuquerque-Jr EC, Melo LFC, Franco TT. Use of solid-phase extraction, high-performance liquid chromatography, and MALDI-TOF identification for [D-Leu1]MCYST-LR analysis in treated water: Validation of the analytical methodology. Canadian Journal of Analytical Sciences & Spectroscopy. 200752(1). (in press)Ruthven, D.M., Goddard, M., Sorption and diffusion of C-8 aromatic-hydrocarbons in faujasite type zeolites. 1. equilibrium isotherms and separation factors (1986) Zeolites, 6 (4), pp. 275-282Ho, Y.S., McKay, G., Pseudo-second order model for sorption processes (1999) Process. Biochem, 34 (5), pp. 451-465Ho, Y.S., McKay, G., Kinetic models for the sorption of dye from aqueous solution by wood (1998) J. Environ. Sci. Health Part B: Process Safety Environ. Protect, 76 (B2), pp. 183-191Low, M.J.D., Kinetics of chemisorption of gases on solids (1960) Chem. Rev, 60 (3), pp. 267-312Chien, S.H., Clayton, W.R., Application of Elovich equation to the kinetics of phosphate release and sorption in soils (1980) Soil Sci. Soc. Am. J, 44 (2), pp. 265-268Santos, E.S., Guirardello, R., Franco, T.T., Preparative chromatography of xylanase using expanded bed adsorption (2002) Journal of chromatography A, 944 (1-2), pp. 217-224Barros, M.A.S.D., Zola, A.S., Arroyo, P.A., Aguiar, E.F.S., Tavares, C.R.G., Equilibrium and dynamic ion exchange studies of Cr3+ on zeolites NaA and NaX (2002) Acta Scientiarum, 24 (6), pp. 1619-1625Geankoplis, C.J., (2003) Transport Processes and Separation Process Principles, , 4 ed. USA: PTR Prentice Hall;Quinlivan, P.A., Li, L., Knappe, D.R.U., Effects of activated carbon characteristics on the simultaneous adsorption of aqueous organic micropollutants and natural organic matter (2005) Water Research, 39 (8), pp. 1663-1673Donati, C., Drikas, M., Hayes, R., Newcombe, G., Microcystin-LR adsorption by powdered activated carbon (1994) Water Research, 28 (8), pp. 1735-1742Pendleton, P., Schumann, R., Wong, S.H., Microcystin-LR adsorption by activated carbon (2001) Journal of Colloid and Interface Science, 240 (1), pp. 1-8Toles, C.A., Marshall, W.E., Johns, M.M., Surface functional groups on acid-activated nutshell carbons (1999) Carbon, 37 (8), pp. 1207-1214Mcdermott, C.M., Feola, R., Plude, J., Detection of cyanobacterial toxins (microcystins) in waters of northeastern Wisconsin by a new immunoassay technique (1995) Toxicon, 33 (11), pp. 1433-1442Ueno, Y., Nagata, S., Tsutsumi, T., Hasegawa, A., Yoshida, F., Suttajit, M., Mebs, D., Vasconcelos, V., Survey of microcystins in environmental water by a highly sensitive immunoassay based on monoclonal antibody (1996) Natural toxins, 4 (6), pp. 271-276Sivonen, K., Jones, G., Cyanobacterial toxins (1999) Toxic Cyanobacteria in Water, pp. 55-124. , A guide to their public health consequences, monitoring and management, and, ed, Routledge, UK: E&FN Spon;Robillot, C., Vinh, J., Puiseux-Dao, S., Hennion, M.C., Hepatotoxin Production Kinetics of the Cyanobacterium Microcystis aeruginosa PCC 7820, as Determined by HPLC-Mass Spectrometry and Protein Phosphatase Bioassay (2000) Environmental Science & Technology, 34 (16), pp. 3372-3378Pyo, D., Moon, D., Adsorption of microcystin LR by activated carbon fibers (2005) Bulletin of the Korean Chemical Society, 26 (12), pp. 2089-2092Yan, H., Gong, A., He, H., Zhou, J., Wei, Y., Lv, L., Adsorption of microcystins by carbon nanotubes (2006) Chemosphere, 62 (1), pp. 142-148Mohamed, Z.A., Carmichael, W.W., An, J., El-Sharouny, H.M., Activated carbon removal efficiency of microcystins in an aqueous cell extract of Microcystis aeruginosa and Oscillatoria tenuis strains isolated from Egyptian freshwaters (1999) Environmental toxicology, 14 (1), pp. 197-20

    Genomic analysis of two phlebotomine sand fly vectors of Leishmania from the New and Old World.

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    Phlebotomine sand flies are of global significance as important vectors of human disease, transmitting bacterial, viral, and protozoan pathogens, including the kinetoplastid parasites of the genus Leishmania, the causative agents of devastating diseases collectively termed leishmaniasis. More than 40 pathogenic Leishmania species are transmitted to humans by approximately 35 sand fly species in 98 countries with hundreds of millions of people at risk around the world. No approved efficacious vaccine exists for leishmaniasis and available therapeutic drugs are either toxic and/or expensive, or the parasites are becoming resistant to the more recently developed drugs. Therefore, sand fly and/or reservoir control are currently the most effective strategies to break transmission. To better understand the biology of sand flies, including the mechanisms involved in their vectorial capacity, insecticide resistance, and population structures we sequenced the genomes of two geographically widespread and important sand fly vector species: Phlebotomus papatasi, a vector of Leishmania parasites that cause cutaneous leishmaniasis, (distributed in Europe, the Middle East and North Africa) and Lutzomyia longipalpis, a vector of Leishmania parasites that cause visceral leishmaniasis (distributed across Central and South America). We categorized and curated genes involved in processes important to their roles as disease vectors, including chemosensation, blood feeding, circadian rhythm, immunity, and detoxification, as well as mobile genetic elements. We also defined gene orthology and observed micro-synteny among the genomes. Finally, we present the genetic diversity and population structure of these species in their respective geographical areas. These genomes will be a foundation on which to base future efforts to prevent vector-borne transmission of Leishmania parasites

    A search for resonances decaying into a Higgs boson and a new particle X in the XH → qqbb final state with the ATLAS detector

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    A search for heavy resonances decaying into a Higgs boson (H) and a new particle (X) is reported, utilizing 36.1 fb−1 of proton–proton collision data at collected during 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. The particle X is assumed to decay to a pair of light quarks, and the fully hadronic final state is analysed. The search considers the regime of high XH resonance masses, where the X and H bosons are both highly Lorentz-boosted and are each reconstructed using a single jet with large radius parameter. A two-dimensional phase space of XH mass versus X mass is scanned for evidence of a signal, over a range of XH resonance mass values between 1 TeV and 4 TeV, and for X particles with masses from 50 GeV to 1000 GeV. All search results are consistent with the expectations for the background due to Standard Model processes, and 95% CL upper limits are set, as a function of XH and X masses, on the production cross-section of the resonance

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

    Combination of searches for Higgs boson pairs in pp collisions at \sqrts = 13 TeV with the ATLAS detector

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    This letter presents a combination of searches for Higgs boson pair production using up to 36.1 fb(-1) of proton-proton collision data at a centre-of-mass energy root s = 13 TeV recorded with the ATLAS detector at the LHC. The combination is performed using six analyses searching for Higgs boson pairs decaying into the b (b) over barb (b) over bar, b (b) over barW(+)W(-), b (b) over bar tau(+)tau(-), W+W-W+W-, b (b) over bar gamma gamma and W+W-gamma gamma final states. Results are presented for non-resonant and resonant Higgs boson pair production modes. No statistically significant excess in data above the Standard Model predictions is found. The combined observed (expected) limit at 95% confidence level on the non-resonant Higgs boson pair production cross-section is 6.9 (10) times the predicted Standard Model cross-section. Limits are also set on the ratio (kappa(lambda)) of the Higgs boson self-coupling to its Standard Model value. This ratio is constrained at 95% confidence level in observation (expectation) to -5.0 &lt; kappa(lambda) &lt; 12.0 (-5.8 &lt; kappa(lambda) &lt; 12.0). In addition, limits are set on the production of narrow scalar resonances and spin-2 Kaluza-Klein Randall-Sundrum gravitons. Exclusion regions are also provided in the parameter space of the habemus Minimal Supersymmetric Standard Model and the Electroweak Singlet Model. For complete list of authors see http://dx.doi.org/10.1016/j.physletb.2019.135103</p

    Searches for lepton-flavour-violating decays of the Higgs boson in s=13\sqrt{s}=13 TeV pp\mathit{pp} collisions with the ATLAS detector

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    This Letter presents direct searches for lepton flavour violation in Higgs boson decays, H → eτ and H → μτ , performed with the ATLAS detector at the LHC. The searches are based on a data sample of proton–proton collisions at a centre-of-mass energy √s = 13 TeV, corresponding to an integrated luminosity of 36.1 fb−1. No significant excess is observed above the expected background from Standard Model processes. The observed (median expected) 95% confidence-level upper limits on the leptonflavour-violating branching ratios are 0.47% (0.34+0.13−0.10%) and 0.28% (0.37+0.14−0.10%) for H → eτ and H → μτ , respectively.publishedVersio
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