48 research outputs found

    Graphite oxide as a support for palladium and rhodium complexes, assessed as catalysts for the partial hydrogenation of 1-heptyne

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    Graphite oxide (GO) was used to anchor [PdCl2(TDA)2] and [RhCl(TDA)3] (TDA =NH2(CH2)12CH3) with 2wt % of metal load. Elemental analysis (EA), FTIR, XPS, XRD and atomic absorption spectroscopy (AA) were the techniques employed for characterization. FTIR and XRD revealed that both complexes were mainly immobilized on the GO surface. The partial hydrogenation of 1-heptyne was the test reaction to evaluate the catalytic behavior of these heterogenized complexes under mild conditions of temperature and pressure in a semi continuous process. The results were compared with those obtained with the Wilkinson catalyst under the same operational conditions. AA analysis revealed that there is no leaching of the complexes during the heterogeneous catalytic evaluations. [RhCl(TDA)3]/GO was the best catalyst due to electronic and steric effects as well as the influence of the support

    Advancing in Schaaf-Yang syndrome pathophysiology: from bedside to subcellular analyses of truncated MAGEL2

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    Background Schaaf-Yang syndrome (SYS) is caused by truncating mutations in MAGEL2, mapping to the Prader-Willi region (15q11-q13), with an observed phenotype partially overlapping that of Prader-Willi syndrome. MAGEL2 plays a role in retrograde transport and protein recycling regulation. Our aim is to contribute to the characterisation of SYS pathophysiology at clinical, genetic and molecular levels. Methods We performed an extensive phenotypic and mutational revision of previously reported patients with SYS. We analysed the secretion levels of amyloid-β 1-40 peptide (Aβ1-40) and performed targeted metabolomic and transcriptomic profiles in fibroblasts of patients with SYS (n=7) compared with controls (n=11). We also transfected cell lines with vectors encoding wild- type (WT) or mutated MAGEL2 to assess stability and subcellular localisation of the truncated protein. Results Functional studies show significantly decreased levels of secreted Aβ1-40 and intracellular glutamine in SYS fibroblasts compared with WT. We also identified 132 differentially expressed genes, including non-coding RNAs (ncRNAs) such as HOTAIR, and many of them related to developmental processes and mitotic mechanisms. The truncated form of MAGEL2 displayed a stability similar to the WT but it was significantly switched to the nucleus, compared with a mainly cytoplasmic distribution of the WT MAGEL2. Based on the updated knowledge, we offer guidelines for the clinical management of patients with SYS. Conclusion A truncated MAGEL2 protein is stable and localises mainly in the nucleus, where it might exert a pathogenic neomorphic effect. Aβ1-40 secretion levels and HOTAIR mRNA levels might be promising biomarkers for SYS. Our findings may improve SYS understanding and clinical management

    Investment in the long-tail of biodiversity data: from local research to global knowledge

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    In business, the "long-tail economy" refers to a market strategy where the gravity center shifts from a few high-demand products to many, varied products focused on small niches. Commercialization of individually low-demand products can be profitable as long as their production cost is low and, all taken together, they aggregate into a big chunk of the market. Similarly, in the "business" of biodiversity data acquisition, we can find several mainstream products that produce zillions of bits of information every year and account for most of the budget allocated to increase our primary data-based knowledge about Earth's biological diversity. These products play a crucial role in biodiversity research. However, along with these large global projects, there is a constellation of small-scale institutions that work locally, but whose contribution to our understanding of natural processes should not be dismissed. These information datasets can be collectively referred to as the "long-tail biodiversity data"

    Prediction of poor outcome in clostridioides difficile infection: A multicentre external validation of the toxin B amplification cycle

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    Producción CientíficaClassification of patients according to their risk of poor outcomes in Clostridioides difficile infection (CDI) would enable implementation of costly new treatment options in a subset of patients at higher risk of poor outcome. In a previous study, we found that low toxin B amplification cycle thresholds (Ct) were independently associated with poor outcome CDI. Our objective was to perform a multicentre external validation of a PCR-toxin B Ct as a marker of poor outcome CDI. We carried out a multicentre study (14 hospitals) in which the characteristics and outcome of patients with CDI were evaluated. A subanalysis of the results of the amplification curve of real-time PCR gene toxin B (XpertTM C. difficile) was performed. A total of 223 patients were included. The median age was 73.0 years, 50.2% were female, and the median Charlson index was 3.0. The comparison of poor outcome and non–poor outcome CDI episodes revealed, respectively, the following results: median age (years), 77.0 vs 72.0 (p = 0.009); patients from nursing homes, 24.4% vs 10.8% (p = 0.039); median leukocytes (cells/μl), 10,740.0 vs 8795.0 (p = 0.026); and median PCR-toxin B Ct, 23.3 vs 25.4 (p = 0.004). Multivariate analysis showed that a PCR-toxin B Ct cut-off <23.5 was significantly and independently associated with poor outcome CDI (p = 0.002; OR, 3.371; 95%CI, 1.565–7.264). This variable correctly classified 68.5% of patients. The use of this microbiological marker could facilitate early selection of patients who are at higher risk of poor outcome and are more likely to benefit from newer and more costly therapeutic options

    Cruise Summary Report - MEDWAVES survey. MEDiterranean out flow WAter and Vulnerable EcosystemS (MEDWAVES)

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    The MEDWAVES (MEDiterranean out flow WAter and Vulnerable EcosystemS) cruise targeted areas under the potential influence of the MOW within the Mediterranean and Atlantic realms. These include seamounts where Cold-water corals (CWCs) have been reported but that are still poorly known, and which may act as essential “stepping stones” connecting fauna of seamounts in the Mediterranean with those of the continental shelf of Portugal, the Azores and the Mid-Atlantic Ridge. During MEDWAVES sampling has been conducted in two of the case studies of ATLAS: Case study 7 (Gulf of Cádiz-Strait of Gibraltar-Alboran Sea) and Case study 8 (Azores). The initially targeted areas in the Atlantic were: the Gazul Mud volcano, in the Gulf of Cádiz (GoC) area, included in the case study 7, and the Atlantic seamounts Ormonde (Portuguese shelf) and Formigas (by Azores), both part of the case study 8. In the Mediterranean the targeted areas were The Guadiaro submarine canyon and the Seco de los Olivos (also known as Chella Bank) seamount. Unfortunately it was not possible to sample in Guadiaro due to time constraints originated by adverse meteorological conditions which obligate us to reduce the time at sea focusing only in 4 of the 5 initially planned areas. MEDWAVES was structured in two legs; the first leg took place from the 21st September (departure from Cádiz harbour in Spain) to the 13th October 2016 (arrival in Ponta Delgada, São Miguel, Azores, Portugal took place the 8th of October due to the meteorological conditions that obligated to conclude the first leg earlier as planned). during the Leg 1 sampling was carried out in Gazul, Ormonde and Formigas. The second leg started the 14th October (departure from Ponta Delgada) and finished the 26th October (arrival in Málaga harbour, Spain). MEDWAVES had a total of 30 effective sampling days, being 6 days not operative due to the adverse meteorological conditions experienced during the first leg which forced us to stay in Ponta Delgada from the 08th to the 13th October. During MEDWAVES the daily routine followed a similar scheme, depending of course on the weather and sea conditions. The main activity during the day, starting early in the morning (around 08:00 AM, once the night activities were finished), was the ROV deployment. Generally a single ROV dive of around 8 hours was performed, however in several occasions two dives were carried out in the same day (see General station list, Appendix II). After the ROV (and sometimes between two dives) the Box Corer and/or Van Veen Grab and/or Multicore was deployed. After these activities, during the night CTD-Rosette deployments and MB was conducted. Accordingly to this schema the scientific personnel worked in the day or in the night watch. A total of 215 sampling stations have been covered in MEDWAVES, using the following sampling gears: Multibeam echosounder, CTD-Rosette, LADCP, Box Corer, Van Veen Grab, Multicorer and a Remotely Operated Vehicle (ROV). Table 1 sumamrised the number of sampling stations conducted with each gear in each sampling zone. Additionally MB surveys have been conducted during the transits between area

    Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study

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    Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders

    Performance, feed utilization, and hepatic metabolic response of weaned juvenile Atlantic bluefin tuna (Thunnus thynnus L.): effects of dietary lipid level and source

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    The development of formulated diets and feeds is essential to increase production of farmed tuna species. There is limited knowledge of this topic, mainly on Pacific Bluefin tuna (Thunnus orientalis) in Japan, whereas no major attempts have been made with Atlantic Bluefin tuna (Thunnus thynnus; ABT). In the present study, two trials were performed using inert formulated diets as on-growing feeds for weaned ABT juvenile in order to establish adequate dietary levels of both lipid and omega-3 long-chain polyunsaturated fatty acids (LC-PUFA). In a first trial, ABT (initial weight = 2.9±0.9g) were fed for 10 days with either a commercial (Magokoro®, MGK) or two experimental feeds with two different lipid levels (15 or 20%) using krill oil (KO) as the single lipid source in order to estimate the suitable lipid content. Fish fed MGK displayed the highest growth, followed by 15KO, with no differences in fish survival. Thus, a lipid content of 15% was considered better than 20% for ABT juveniles. In the second trial, fish (initial weight = 3.3 ± 0.6g) were fed either MGK, 15KO or a feed containing 15% lipid with a combination (1:1, v/v) KO and rapeseed oil (RO) (15KORO). Fish fed 15KO and 15KORO showed the highest growth in terms of weight and fork length (including weight gain and SGR). Increasing dietary lipid level or adding RO to the feeds did not increase liver lipid content. The liver fatty acid profile largely reflected dietary intake confirming very limited LC-PUFA biosynthetic activity for this teleost species. In this respect, liver of fish fed 15KO and 20KO displayed the highest contents of docosahexaenoic acid (DHA). The hepatic expression of genes of lipid and fatty acid metabolism, transcription factors, and antioxidant enzymes was investigated with many of the genes showing regulation by both dietary lipid and LC-PUFA contents. The present study showed promising results that suggested ABT juveniles can be on grown on inert dry feeds that supported good fish growth and the accumulation of the health-promoting fatty acid DHA. Further studies are required in order to fully elucidate lipid and fatty acid requirements of this iconic species regarding dietary sources and production costs.En prensa1,52

    Campo Experimental Potrok Aike : resultado de 15 años de labor técnica

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    Libro de edición impresa publicado en 2005 y con edición electrónica en el año 2016.Al crearse, en el año 1985, la Estación Experimental Santa Cruz en el marco del convenio entre el INTA y la provincia de Santa Cruz surgió la necesidad de contar con un campo donde se pudieran desarrollar trabajos de investigación en ganadería, fundamentalmente ovina, y en pastizales naturales con el necesario control de diferentes variables productivas y ambientales. El gobierno provincial cedió un predio ubicado al sur de la provincia de Santa Cruz, en una zona representativa de la Estepa magallánica seca, en el extremo austral de la Patagonia. Esta publicación recopiló y organizó los datos e información dispersa resultante de más de 15 años de trabajo, y transformó esa materia prima en información accesible para técnicos y productores. Conformada por el aporte de distintos autores ofrece la información de base para describir el ambiente del Campo Experimental Potrok Aike, más las conclusiones de ensayos y experiencias llevadas a cabo en el lugar, que son perfectamente extrapolables a todo el sur provincial.EEA Santa CruzFil: Alegre, María Beatriz. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Alegre, María Beatriz. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Alegre, María Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Anglesio, Francisco. Secretaría de Medio Ambiente. Provincia de Santa Cruz. Santa Cruz; Argentina.Fil: Baetti, Carlos. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Baetti, Carlos. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Bahamonde, Héctor Alejandro. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Bahamonde, Héctor Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Barría, Julio. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Battini, Alberto. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Baumann, Osvaldo. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Borrelli, Pablo. Consultor privado. Buenos Aires; Argentina.Fil: Camejo, Ana María. Consultor privado. Trelew; Argentina.Fil: Castillo, Miguel. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Cibils, Andrés. New México State University. Department of Animal and Range Sciences; Estados UnidosFil: Ciurca, Lorena. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Clifton, Guillermo Raimundo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Clifton, Guillermo Raimundo. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Culun, Victor Pascual. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Escalada, Julián. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Ferrante, Daniela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Ferrante, Daniela. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Gismondi, Daniel. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: González, Liliana. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Grima, Daniel. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Humano, Gervasio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Iacomini, Mónica. Secretaría de la Producción. Provincia de Santa Cruz. Santa Cruz; Argentina.Fil: Iglesias, Roberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Chubut; Argentina.Fil: Kofalt, Bustamante Rosa. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Kofalt, Bustamante Rosa. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Kofalt, Bustamante Rosa. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Lamoureux, Mabel Noemi. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Lamoureux, Mabel Noemi. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Larrosa, José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Manero, Amanda. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Manero, Amanda. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Marcolín, Arrigo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina.Fil: Mascó, Mercedes. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Mascó, Mercedes. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Mascó, Mercedes. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Migliora, Horacio. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Milicevic, Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; ArgentinaFil: Montes, Leopoldo. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro Regional Patagonia Sur; Argentina.Fil: Oliva, Gabriel Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Oliva, Gabriel Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Osses, Julio Angel. Consejo Agrario Provincial- Provincia de Santa Cruz; Argentina.Fil: Paredes, Paula. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peinetti, Raúl. Universidad Nacional de La Pampa. Facultad de Agronomía; Argentina.Fil: Rial, Pablo Eduardo. Ministerio de Economía y Obras Públicas. Provincia de Santa Cruz; Argentina.Fil: Rial, Pablo Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Romero, Rubén. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Rosales, Valeria. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Salazar, Daniel. LU85 TV Canal 9. Auxiliar en Control de Erosión de Suelos. Provincia de Santa Cruz; Argentina.Fil: Tapia, Hector Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Chubut; Argentina.Fil: Torra, Francisco. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina.Fil: Zerpa, Débora. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina

    Un caso de hipoplasia cerebelar humana asociada a consaguinidad múltiple

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    Un caso de hipoplasia cerebelar humana asociada a consaguinidad múltiple. Human cerebellar hypoplasia related to multiple consaguinity: study of a cas

    Evaluación del contenido de metales en suelos y tejidos comestibles de Allium fistulosum L. cultivado en zonas cercanas al volcán Tungurahua.

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    The Tungurahua volcano, located in the eastern mountain range of Ecuador, since its reactivation in 1999 has had several phases of volcanic activity, which have produced gas, ash and lava emissions. These emissions release a large amount of metals to nearby soils that are currently used for agricultural purposes. Metal pollution can cause serious problems for human health; while other metals are necessary as nutrients in most agricultural crops. In this investigation, the metal content in agricultural soils of the Quero canton was evaluated, as well as its bioavailability and content in the culture of Allium fistulosum L., in order to obtain information on the impact of potentially polluting metals (cadmium, lead, nickel, strontium, cobalt, copper and zinc) and nutrients (potassium, magnesium, iron and manganese) on crops. For the estimation of total metals in soil an acid digestion was performed; for bioavailable metals an extractant mixture (EDTA-Triethanolamine-CaCl2, pH 7) was used and for the branch onion a calcination followed by acid digestion was carried out. The quantification of the metals was carried out by flame atomic absorption spectroscopy or graphite furnace. The results showed that the metal content, both in the soil samples and in the branch onion, was below the maximum values allowed in the local regulations for all the metals studied. In addition,the intake of the metal by the branch onion was independent of the bioavailable fraction.O vulcão Tungurahua, localizado na cordilheira oriental do Equador, desde a sua reactivação em 1999, entrou em várias fases de actividade vulcânica, produzindo emissões de gás, cinzas e lava. Estas emissões libertam uma grande quantidade de metais em solos próximos que são actualmente utilizados para fins agrícolas. A contaminação por metais pode causar sérios problemas para a saúde humana, enquanto outros metais são necessários como nutrientes na maioria das culturas agrícolas. Nesta investigação, o conteúdo metálico dos solos agrícolas em Quero canton, a sua biodisponibilidade e o conteúdo de Allium fistulosum L. foram avaliados a fim de obter informações sobre o impacto de metais potencialmente contaminantes (cádmio, chumbo, níquel, estrôncio, cobalto, cobre e zinco) e nutrientes (potássio, magnésio, ferro e manganês) nas culturas. Para a estimativa do total de metais no solo, foi realizada uma digestão ácida; para os metais biodisponíveis foi utilizada uma mistura extractante (EDTA-Trietanolamina-CaCl2, pH 7) e para as cebolas ramificadas foi realizada uma calcinação seguida de digestão ácida. A quantificação dos metais foi realizada por meio de espectroscopia de absorção atómica (AAS) por chama ou por forno de grafite. Os resultados mostraram que o teor de metal nas amostras de solo e de cebola de ramo estava abaixo dos valores máximos permitidos nas normas locais para todos os metais estudados; além disso, a ingestão de metal por cebola de ramo era independente da fracção biodisponível.El volcán Tungurahua, ubicado en la cordillera oriental de Ecuador, desde su reactivación en 1999 ha entrado en varias fases de actividad volcánica, produciendo emisiones de gas, cenizas y lava. Estas emisiones liberan una gran cantidad de metales a suelos cercanos que, en la actualidad, se emplean con fines agrícolas. La contaminación por metales puede provocar graves problemas para la salud humana; mientras que otros metales son necesarios como nutrientes, en la mayoría de los cultivos agrícolas. En esta investigación, se evaluó el contenido de metales en suelos agrícolas del cantón Quero, su biodisponibilidad y el contenido en el cultivo de Allium fistulosum L., con la finalidad de obtener información sobre el impacto de metales potencialmente contaminantes (cadmio, plomo, níquel, estroncio, cobalto, cobre y cinc) y nutrientes (potasio, magnesio, hierro y manganeso) sobre los cultivos. Para la estimación de metales totales en el suelo se realizó una digestión ácida; para metales biodisponibles se empleó una mezcla extractante (EDTA-Trietanolamina-CaCl2, pH 7) y para la cebolla de rama se realizó una calcinación seguida de digestión ácida. La cuantificación de los metales se realizó mediante espectroscopia de absorción atómica (EAA) de llama o de hornode grafito. Los resultados mostraron que el contenido de metales, tanto en las muestras de suelo como en cebolla de rama, estaba por debajo de los valores máximos permitidos en las normas locales para todos los metales estudiados; además, la ingesta del metal por la cebolla de rama fue independiente de la fracción biodisponible
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