174 research outputs found
Factors controlling hydrothermal nickel and cobalt mineralization—some suggestions from historical ore deposits in Italy
No full textWe compare three poorly known, historical Ni-Co-bearing hydrothermal deposits in different geological settings in Italy: The Ni-Co-As-Sb-Au-bearing Arburese vein system (SW Sardinia),the Co-Ni-As-rich Usseglio vein system (Piedmont), and the small Cu-Ag-Co-Ni-Pb-Te-Se stockwork at Piazza (Liguria).These deposits share various (mineralogical, chemical, thermal, andstable isotopic) similarities to the Five Element Vein-type ores but only the first two were economic for Co-Ni. The Sardinian Ni-rich veins occur in Paleozoic basement near two Variscan plutons. Like theCo-rich Usseglio vein system, the uneconomic Piazza deposit is hostedin an ophiolite setting anomalous for Co. The Sardinian and Usseglio deposits share a polyphasic assemblage with Ni-Co-As-Sb-Bi followed by Ag-base metal sulfides, in siderite-rich gangue, whereas Piazza shows As-free, Ag-Pb-Te-Se-bearing Co-Ni-Cu sulfides, in prehnite-chlorite gangue. Fluid inclusions indicated Co-Ni arsenide precipitation at ≈170 °C for Usseglio, whereas forthe Sardinian system late sulfide deposition occurred within the 5 -126 °C range. Ore fluids in both systems are NaCl-CaCl2-bearing basinal brines. The chlorite geothermometer at Piazza provides the range of 200-280 °C for ore deposition from CO2-poor fluids. Enrichments in Se and negative °13C in carbonates suggest interaction withcarbonaceous shales. These deposits involve issues about source rocks,controls on Co/Ni and possible role of arsenic and carbonate components towards economic mineralization
Zwitterion-Coated Iron Oxide Nanoparticles: Surface Chemistry and Intracellular Uptake by Hepatocarcinoma (HepG2) Cells
No full textNanoparticles
(NPs) have received much attention in recent years
for their diverse potential biomedical applications. However, the
synthesis of NPs with desired biodistribution and pharmacokinetics
is still a major challenge, with NP size and surface chemistry being
the main factors determining the behavior of NPs in vivo. Here we
report on the surface chemistry and in vitro cellular uptake of magnetic
iron oxide NPs coated with zwitterionic dopamine sulfonate (ZDS).
ZDS-coated NPs were compared to similar iron oxide NPs coated with
PEG-like 2-[2-(2-methoxyethoxy)ethoxy]acetic acid (MEEA) to investigate
how surface chemistry affects their in vitro behavior. ZDS-coated
NPs had a very dense coating, guaranteeing high colloidal stability
in several aqueous media and negligible interaction with proteins.
Treatment of HepG2 cells with increasing doses (2.5–100 μg
Fe/mL) of ZDS-coated iron oxide NPs had no effect on cell viability
and resulted in a low, dose-dependent NP uptake, inferior than most
reported data for the internalization of iron oxide NPs by HepG2 cells.
MEEA-coated NPs were scarcely stable and formed micrometer-sized aggregates
in aqueous media. They decreased cell viability for dose ≥50
μg Fe/mL, and were more efficiently internalized than ZDS-coated
NPs. In conclusion, our data indicate that the ZDS layer prevented
both aggregation and sedimentation of iron oxide NPs and formed a
biocompatible coating that did not display any biocorona effect. The
very low cellular uptake of ZDS-coated iron NPs can be useful to achieve
highly selective targeting upon specific functionalization
Conditions for hydrothermal cobalt and nickel mineralization – suggestions from some little known, historical ore deposits in Italy
No full textWe present ongoing research about three poorly known, historical Ni-Co-bearing hydrothermal deposits in different geological contexts: the Ni-Co-As-Sb-Au-bearing Arburese vein system (SW Sardinia), the Co-As-rich Usseglio vein system (Piedmont) and the small Cu-Ag-Co-Ni-Pb-Te-Se stockwork ore at Piazza (eastern Liguria). These deposits share some similarities to the Five Element Vein-type, Co-Ni-Ag-Bi-As ores but only the first two display km-sized development and were economic for Co and Ni. The Arburese Ni-rich veins occur in Paleozoic basement near two Variscan plutons. The Co-rich Usseglio and Piazza deposits share ophiolitic contexts: the Usseglio veins crosscut metabasalts near the Lanzo peridotite massif, while the Piazza stockwork crosscuts low-grade metamorphic gabbro of the Bracco ophiolite massif. The Arburese and Usseglio deposits share a complex mineral assemblage with early Bi-bearing Ni-Co arsenides-sulfarsenides followed by Ag-base metal sulfides, in siderite-quartz-baryte gangue. The Piazza deposit stands apart with its early Ag-Pb-Bi telluride-selenide stage with Co-Ni sulfides plus bornite replaced by chalcopyrite, in prehnite-albite-chlorite gangue. Piazza shares its Se-rich character with the Arburese veins, which host Se in base metal sulfides. Preliminary geothermometric estimates are provided by fluid inclusion analyses (Usseglio and Arburese) and chlorite composition (Piazza). Co-Ni arsenide precipitatation occurred at ≈200°C (0.5 kbar) after a vigorous boiling episode depositing baryte, while later base metal sulfide deposition occurred at 80÷140°C. Ore fluids are NaCl-CaCl2-bearing brines (18÷25 equiv. mass% NaCl). Ore carbonates display stable isotope signatures compatible with such low temperature brines, typical for five element vein-type deposits. Vein-related chlorites at Piazza provide higher temperatures for ore deposition in the range of 200÷280°C (avg 230°C), and the carbonate-free prehnite-feldspar assemblage is compatible with CO2-degassed, alkali chloride waters. No data are available on hydrocarbons in the ore fluids, although observed enrichments in Se and negative δ13C in carbonates suggest interaction with carbonaceous shales. In their own regional metallogenic contexts the three deposits stand out and open questions about source rocks and controls on Co/Ni: e.g., within the highly mineralized, Ni-free southern Sardinian crust the Arburese Ni-Co-As vein system is unique, as is the Usseglio Co-As vein system within the western Alps rich in ophiolites and post-peak hydrothermal deposits. The northern Appenninic ophiolites, hosting the unique Cu-Ag-Co-Ni-Pb-Te-Se Piazza deposit, may actually have the greatest potential for hydrothermal Co-Ni mineralization as their many oceanic exhalative Cu-Fe deposits are highly anomalous in Co. Piazza ore fluids recycled metals of various provenance, like Co and Ag, but no economic ore was formed. Could the missing arsenic and carbonate components be part of the problem
Relationships among macroinvertebrate community structure, bio/ecological trait profiles, and environmental descriptors in European human-altered streams
No full textOver the last decades, depletion in freshwater quality due to increasing pollution has become an important problem, especially in Europe where most streams drain catchments that are relatively densely populated. Effluents from waste water treatment plants (WWTP) represent one of the causes of stream ecosystem degradation (PAUL & MEYER 2001). This attains special relevance in Mediterranean countries, where the scarcity of water limits the dilution of pollution. In this context, the use of adequate ecological indicators is particularly helpful in assessing the impact of environmental changes (JOHNSON et al. 2006). Macroinvertebrates are good indicators of stream pollution (e.g., biotic indices) successfully used in monitoring studies (VERDONSCHOT & MOOG 2006). Recently, the use of trait profiles has enabled a reliable ecological indication, not only characterizing community structure (CHARVET et al. 1998), but also permitting the functional comparison of communities across larger geographical scales (DOLEDEC et al. 2006). This study evaluated the impact of WWTP inputs on stream functioning under different climatic conditions across Europe. We investigated the relationships between macroinvertebrate communities (i.e. taxonomic composition and traits profiles) and environmental variables in two ecologically contrasted reaches (upstream and downstream a WWTP) for 10 European streams
Factors Controlling Hydrothermal Nickel and Cobalt Mineralization—Some Suggestions from Historical Ore Deposits in Italy
No full textWe compare three poorly known, historical Ni�Co-bearing hydrothermal deposits in different geological settings in Italy: The Ni-Co-As-Sb-Au-bearing Arburese vein system (SW Sardinia),the Co-Ni-As-rich Usseglio vein system (Piedmont), and the small Cu-Ag-Co-Ni-Pb-Te-Se stockwork at Piazza (Liguria).These deposits share various (mineralogical, chemical, thermal, andstable isotopic) similarities to the Five Element Vein-type ores but only the first two were economic for Co-Ni. The Sardinian Ni-rich veins occur in Paleozoic basement near two Variscan plutons. Like theCo-rich Usseglio vein system, the uneconomic Piazza deposit is hostedin an ophiolite setting anomalous for Co. The Sardinian and Usseglio deposits share a polyphasic assemblage with Ni-Co-As-Sb-Bi followed by Ag-base metal sulfides, in siderite-rich gangue, whereas Piazza shows As-free, Ag-Pb-Te-Se-bearing Co-Ni-Cu sulfides, in prehnite-chlorite gangue. Fluid inclusions indicated Co-Ni arsenide precipitation at ≈170 °C for Usseglio, whereas forthe Sardinian system late sulfide deposition occurred within the 5 -126 °C range. Ore fluids in both systems are NaCl-CaCl2-bearing basinal brines. The chlorite geothermometer at Piazza provides the range of 200-280 °C for ore deposition from CO2-poor fluids. Enrichments in Se and negative °13C in carbonates suggest interaction withcarbonaceous shales. These deposits involve issues about source rocks,controls on Co/Ni and possible role of arsenic and carbonate components towards economic mineralization
Conditions for hydrothermal cobalt and nickel mineralization – suggestions from some little known, historical ore deposits in Italy
No full textWe present ongoing research about three poorly known, historical Ni-Co-bearing hydrothermal deposits in different geological contexts: the Ni-Co-As-Sb-Au-bearing Arburese vein system (SW Sardinia), the Co-As rich Usseglio vein system (Piedmont) and the small Cu-Ag-Co-Ni-Pb-Te-Se stockwork ore at Piazza (eastern Liguria). These deposits share some similarities to the Five Element Vein-type, Co-Ni-Ag-Bi-As ores but only the first two display km-sized development and were economic for Co and Ni. The Arburese Ni-rich veins occur in Paleozoic basement near two Variscan plutons. The Co-rich Usseglio and Piazza deposits share ophiolitic contexts: the Usseglio veins crosscut metabasalts near the Lanzo peridotite massif, while the Piazza stockwork crosscuts low-grade metamorphic gabbro of the Bracco ophiolite massif. The Arburese and Usseglio deposits share a complex mineral assemblage with early Bi-bearing Ni-Co arsenides-sulfarsenides followed by Ag base metal sulfides, in siderite-quartz-baryte gangue. The Piazza deposit stands apart with its early Ag-Pb-Bi telluride-selenide stage with Co-Ni sulfides plus bornite replaced by chalcopyrite, in prehnite-albite-chlorite gangue. Piazza shares its Se-rich character with the Arburese veins, which host Se in base metal sulfides. Preliminary geothermometric estimates are provided by fluid inclusion analyses (Usseglio and Arburese) and chlorite composition (Piazza). Co-Ni arsenide precipitatation occurred at ≈200°C (0.5 kbar) after a vigorous boiling episode depositing baryte, while later base metal sulfide deposition occurred at 80÷140°C. Ore fluids are NaCl-CaCl2-bearing brines (18÷25 equiv. mass% NaCl). Ore carbonates display stable isotope signatures compatible with such low temperature brines, typical for five element vein-type deposits. Vein-related chlorites at Piazza provide higher temperatures for ore deposition in the range of 200÷280°C (avg 230°C), and the carbonate-free prehnite-feldspar assemblage is compatible with CO2-degassed, alkali chloride waters. No data are available on hydrocarbons in the ore fluids, although observed enrichments in Se and negative δ13C in carbonates suggest interaction with carbonaceous shales. In their own regional metallogenic contexts the three deposits stand out and open questions about source rocks and controls on Co/Ni: e.g., within the highly mineralized, Ni-free southern Sardinian crust the Arburese Ni-Co-As vein system is unique, as is the Usseglio Co-As vein system within the western Alps rich in ophiolites and post-peak hydrothermal deposits. The northern Apenninic ophiolites, hosting the unique Cu-Ag-Co-Ni-Pb-Te-Se Piazza deposit, may actually have the greatest potential for hydrothermal Co-Ni mineralization as their many oceanic exhalative Cu-Fe deposits are highly anomalous in Co. Piazza ore fluids recycled metals of various provenance, like Co and Ag, but no economic ore was formed. Could the missing arsenic and carbonate components be part of the problem
The role of Fumonisins in the biological interaction between Fusarium verticillioides and Sitophilus zeamais
No full textThe aim of the current study was to investigate the entomopathogenic capacity of the mold Fusarium verticillioides and the effect of its mycotoxins fumonisins, on the grain beetle Sitophilus zeamais. We evaluated the capacity of this fungus to infect live insects, the antifungal activity of constituents of the insect’s epicuticle, and the effect of a fumonisin extract on the fitness of the insects. We found that F. verticillioides could not penetrate the cuticle of S. zeamais and that the fumonisin extract had no negative effects on the fitness of the insects. However, the progeny of the insects increased, and the fumonisin extract had repellent effects. This is the first report about the effects of fumonisins on the relationship between F. verticillioides and S. zeamais, which may provide useful information about interactions between pathogenic microorganisms and insects, especially on stored product pests.Fil: Usseglio, Virginia Lara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Dambolena, José Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Martinez, M. J.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Zunino, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin
DATA SET for "Upregulation of breathing rate during running exercise by central locomotor circuits in mice", by Hérent et al., 2023.
No full textThis repository contains the raw histology images for the following publication:Hérent C, Diem S, Usseglio G, Fortin G, Bouvier J. Upregulation of breathing rate during running exercise by central locomotor circuits in mice, Nature Communications, 2023.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV
Insect-corn kernel interaction: Chemical signaling of the grain and host recognition by Sitophilus zeamais
No full textIn living organisms, the cuticle has structural functions and is involved through chemical signaling in biological interactions such as plant-insect and provides protection against biotic and abiotic factors, thereby avoiding desiccation or the attack of predators. The objective of this study was to investigate the participation of the epicuticle in the maize kernel-Sitophilus zeamais interaction. The GC-MS analysis of the epicuticle extract demonstrated the presence of aliphatic hydrocarbons, alcohols, ethers, fatty acids, sterols and their derivatives. The results of bioassays show that the epicuticle of maize has a primordial role in its interaction with S. zeamais, and participates in the recognition and attraction to the food source, as well as regulating its reproduction. In addition the compounds present in the epicuticle extract may act as signal molecules and development regulators. This study reveals the effect of the maize kernel cuticle on Sitophilus behavior and contributes to the understanding of the interaction.Fil: Usseglio, Virginia Lara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; ArgentinaFil: Dambolena, José Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Merlo, Carolina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Ciencias y Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Departamento de Recursos Naturales. Cátedra de Microbiología Agrícola; ArgentinaFil: Peschiutta, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zunino, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin
New insecticide delivery method for the control of Sitophilus zeamais in stored maize
No full textMaize kernel deterioration caused by the action of insects has led to an urgent need to develop new control methods against the maize weevil, Sitophilus zeamais, one of the major pests found in silo bags during the storage of maize. Here, we evaluated the insecticidal efficiency of plasticized and unplasticized cotton matrices (deliveries), loaded with R-(+)-pulegone, (−)-carvone, 2-decanone and trans-2-hexenol against S. zeamais. R-(+)- pulegone was the only compound that produced weevil mortality. Plasticized delivery loaded with R-(+)-pulegone achieved a 90% mortality on the 12th day, with mortality values recorded of above 96% over the course of 30 days. R-(+)-pulegone from plasticized delivery was released more slowly compared to unplasticized delivery. Moreover, delivery loaded with R-(+)-pulegone did not show phytotoxicity in maize kernels. Hence, due to its effectiveness against the weevil and the lack of phytotoxic activity against maize kernels, plasticized delivery loaded with R-(+)-pulegone represents a promising material for S. zeamais control. However, large-scale studies are needed in order to evaluate its potential use in grain storage systems.Fil: Peschiutta, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Brito, Vanessa Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Achimón, Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zunino, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Usseglio, Virginia Lara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin
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