40 research outputs found

    Biosorption of Chromium (VI) from Aqueous Solutions onto Fungal Biomass

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    The biosorption of chromium (VI) on eighteen different natural biosorbents: Natural sediment, chitosan, chitin, Aspergillus flavus I-V, Aspergillus fumigatus I-ll, Helmintosporium sp, Cladosporium sp, Mucor rouxii mutant, M. rouxii IM-80, Mucor sp-I and 2, Candida albicans and Cryptococcus neoformans was studied in this work. It was found that the biomass of C. neoformans, natural sediment, Helmintosporium sp and chitosan was more efficient to remove chromium (VI) (determined spectrophotometrically at 540 nm using diphenylcarbazide as the complexing agent) achieving the. following percentage of removals: 98%, 98% and 63%, respectively. The highest adsorption was obtained with C. neoformans and Helmintosporium sp at pH 2.0 and 4.0 + 0.2, respectively, at 28∘C after 24 hours of incubation, with 0.2 mg/L of cellular biomass

    Study of the near-barrier scattering of 8 He on 208 Pb

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    The structure and dynamics of 8He have been studied through the collision process with a 208 Pb target at energies of 22 and 16 MeV, above and below the Coulomb barrier, respectively. The energy and angular distributions of the elastically scattered 8He and the 6,4He fragments were measured. In this paper, we discuss the method used to determine the effective position of the beam spot on the reaction target and the scattering and solid angles of each pixel of the detector array.Ministerio de Economía y Competitividad PA2010-22131-C021-01, FPA2014-59954-C3-1-PMinistry of Science and Higher Education of Poland N202 03363European Science Foundation EUI2009-0416

    Interaction of 8He with 208Pb at near-barrier energies: 4He and 6He production

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    Angular distributions for the inclusive 4He and 6He production cross sections in the 8He+208Pb system at incident energies of 16 and 22 MeV measured at the SPIRAL facility of the GANIL laboratory are presented. Using a combination of kinematical arguments and distorted wave Born approximation (DWBA) calculations, neutron transfer reactions were inferred to be the dominant contributors to both inclusive cross sections. Model-dependent values for the ratios of two- to one-neutron stripping, s2n/s1n, were derived and compared with previous results for 8He and 6He projectiles incident on other heavy targets. Three- and four-neutron stripping were inferred to be the main processes leading to 4He production, although the exact mechanism remains to be elucidated.The authors would like to thank the staff of the GANIL accelerator facility for providing the high-quality 8He beam. This work was supported in part by Grants No. FPA-2010-22131-CO2-01 (FINURA) and No. FPA2013-47327-C2-1-R from the Spanish Ministry of Economy and Competitiveness, UNAM-PAPIIT IA103218 (Mexico); Grant No. N202 033637 from the Ministry of Science and Higher Education of Poland; the National Science Centre of Poland under Contracts No. 2013/08/M/ST2/00257 (LEA-COPIGAL) and No. 2014/14/M/ST2/00738 (COPIN-INFN Collaboration); and Grant No. EUI2009-04163432 (EUROGENESIS) from the European Science Foundation

    Sub-barrier fusion of 6He with 206Pb

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    Cross-sections for the production of 210Po nuclei in 6He + 206Pb collisions over the incident energy range 14–18MeV were measured by means of the activation technique and a radiochemical analysis. The elastic scattering at 18.0MeV was also measured providing a precise value for the 210Po production cross-section at this energy. The results are at variance with the earlier experimental data and rather in accord with the predictions of a density-dependent barrier penetration model for the fusion process. A proper treatment of beam energy distribution for the evaluation of the activation data is discussed

    Breakup and neutron-transfer effects on 6He+206Pb elastic scattering below the Coulomb barrier

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    The elastic scattering and inclusive α-particle yield for the 6He + 206Pb system at an incident energy of 18 MeV, just below the nominal Coulomb barrier, have been measured. The α-particle yield at forward angles is also reported. The data are analyzed by means of continuum-discretized coupled-channels, distorted wave Born approximation, and coupled reaction channels calculations. Couplings to the one-neutron- and two-neutron-transfer reactions are found to be able to account for most of the absorption in the entrance channel.This work was supported in part by Grant No. FPA2010-22131-C02-01 from the Spanish Ministry of Science

    ECOS-LINCE : a high-intensity heavy-ion facility for nuclear structure and reactions

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    Presented at the XXXIV Mazurian Lakes Conference on Physics, Piaski, Poland, September 6–13, 2015During the last years, the ECOS working group has been considering the construction of a new high-intensity accelerator of stable ion beams for the next Long-Range Plan of the nuclear physics community in Europe. The new facility (LINCE) will be a multi-user facility dedicated to ECOS science: fundamental physics, astrophysics, nuclear structure and reaction dynamics. In this paper, we summarize preliminary design studies of the low-energy part of this facility based on the use of a multi-ion supercon- ducting linac.Work partially supported by the Spanish Government under the grant Feder-Interconnecta “Aceltec” ITC-20111070. The authors are also grateful to the companies Alter Technology-Tüv, Avs, Cibernos, Elitt Energy, Faysol, Idom, and Tti Norte for partial funding of this work and active participation in the design and prototyping carried-out in this study

    Near barrier scattering of 8He on 208Pb

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    The exotic nucleus 8He is investigated by means of the measurement of the angular distributions of the elastic channel and the 6He and 4He fragment yields produced in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of 8He and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reporte

    Near barrier scattering of 8He on 208Pb

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    The exotic nucleus 8He is investigated by means of the measurement of the angular distributions of the elastic channel and the 6He and 4He fragment yields produced in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of 8He and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reported

    Data sources for drug utilization research in Latin American countries—A cross-national study: DASDUR-LATAM study

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    Purpose: Drug utilization research (DUR) contributes to inform policymaking and to strengthen health systems. The availability of data sources is the first step for conducting DUR. However, documents that systematize these data sources in Latin American (LatAm) countries are not known. We compiled the potential data sources for DUR in the LatAm region. Methods: A network of DUR experts from nine LatAm countries was assembled and experts conducted: (i) a website search of the government, academic, and private health institutions; (ii) screening of eligible data sources, and (iii) liaising with national experts in pharmacoepidemiology (via an online survey). The data sources were characterized by accessibility, geographic granularity, setting, sector of the data, sources and type of the data. Descriptive analyses were performed. Results: We identified 125 data sources for DUR in nine LatAm countries. Thirty-eight (30%) of them were publicly and conveniently available; 89 (71%) were accessible with limitations, and 18 (14%) were not accessible or lacked clear rules for data access. From the 125 data sources, 76 (61%) were from the public sector only; 46 (37%) were from pharmacy records; 43 (34%) came from ambulatory settings and; 85 (68%) gave access to individual patient-level data. Conclusions: Although multiple sources for DUR are available in LatAm countries, the accessibility is a major challenge. The procedures for accessing DUR data should be transparent, feasible, affordable, and protocol-driven. This inventory could permit a comparison of drug utilization between countries identifying potential medication-related problems that need further exploration.Fil: Lopes, Luciane C.. University Of Sorocaba; BrasilFil: Salas, Daiana Maribel. University of Pennsylvania; Estados UnidosFil: Osorio de Castro, Claudia Garcia Serpa. Fundación Oswaldo Cruz; BrasilFil: Freitas Leal, Lisiane. McGill University; CanadáFil: Doubova, Svetlana V.. Mexican Institute of Social Security; MéxicoFil: Cañás, Martín. Universidad Nacional Arturo Jauretche; Argentina. Federación Médica de la Provincia de Buenos Aires; ArgentinaFil: Dreser, Anahi. Instituto Nacional de Salud Pública; MéxicoFil: Acosta, Angela. Universidad ICESI; ColombiaFil: Oliveira Baldoni, Andre. Federal University of São João Del-Rei; BrasilFil: de Cássia Bergamaschi, Cristiane. University of Sorocaba; BrasilFil: Marques Mota, Daniel. Brazilian Health Regulatory Agency; BrasilFil: Gómez Galicia, Diana L.. Universidad Autónoma del Estado de Morelos; MéxicoFil: Sepúlveda Viveros, Dino. Universidad de Chile; ChileFil: Narvaez Delgado, Edgard. No especifíca;Fil: da Costa Lima, Elisangela. Universidade Federal do Rio de Janeiro; BrasilFil: Chandia, Felipe Vera. Pontificia Universidad Católica de Chile; ChileFil: Ferre, Felipe. Universidade Federal de Minas Gerais; BrasilFil: Marin, Gustavo Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Olmos, Ismael. State Health Services Administration; UruguayFil: Zimmermann, Ivan R.. Universidade do Brasília; BrasilFil: Fulone, Izabela. University of Sorocaba; BrasilFil: Roldán Saelzer, Juan. Instituto de Salud Pública; ChileFil: Sánchez Salgado, Juan Carlos. No especifíca;Fil: Castro Pastrana, Lucila I.. Universidad de Las Américas de Puebla; MéxicoFil: de Souza, Luiz Jupiter Carneiro. Fundación Oswaldo Cruz; BrasilFil: Machado Beltrán, Manuel. Universidad Nacional de Colombia; ColombiaFil: Tolentino Silva, Marcus. University of Sorocaba; BrasilFil: Mena, María Belén. Universidad Central del Ecuador; EcuadorFil: de França Fonteles, Marta Maria. Universidade Federal do Ceara; BrasilFil: Urtasun, Martín Alejandro. Universidad Nacional Arturo Jauretche; Argentina. Federación Médica de la Provincia de Buenos Aires; Argentin

    Un examen actualizado de la percepción de las barreras para la implementación de la farmacogenómica y la utilidad de los pares fármaco/gen en América Latina y el Caribe

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    La farmacogenómica (PGx) se considera un campo emergente en los países en desarrollo. La investigación sobre PGx en la región de América Latina y el Caribe (ALC) sigue siendo escasa, con información limitada en algunas poblaciones. Por lo tanto, las extrapolaciones son complicadas, especialmente en poblaciones mixtas. En este trabajo, revisamos y analizamos el conocimiento farmacogenómico entre la comunidad científica y clínica de ALC y examinamos las barreras para la aplicación clínica. Realizamos una búsqueda de publicaciones y ensayos clínicos en este campo en todo el mundo y evaluamos la contribución de ALC. A continuación, realizamos una encuesta regional estructurada que evaluó una lista de 14 barreras potenciales para la aplicación clínica de biomarcadores en función de su importancia. Además, se analizó una lista emparejada de 54 genes/fármacos para determinar una asociación entre los biomarcadores y la respuesta a la medicina genómica. Esta encuesta se comparó con una encuesta anterior realizada en 2014 para evaluar el progreso en la región. Los resultados de la búsqueda indicaron que los países de América Latina y el Caribe han contribuido con el 3,44% del total de publicaciones y el 2,45% de los ensayos clínicos relacionados con PGx en todo el mundo hasta el momento. Un total de 106 profesionales de 17 países respondieron a la encuesta. Se identificaron seis grandes grupos de obstáculos. A pesar de los continuos esfuerzos de la región en la última década, la principal barrera para la implementación de PGx en ALC sigue siendo la misma, la "necesidad de directrices, procesos y protocolos para la aplicación clínica de la farmacogenética/farmacogenómica". Las cuestiones de coste-eficacia se consideran factores críticos en la región. Los puntos relacionados con la reticencia de los clínicos son actualmente menos relevantes. Según los resultados de la encuesta, los pares gen/fármaco mejor clasificados (96%-99%) y percibidos como importantes fueron CYP2D6/tamoxifeno, CYP3A5/tacrolimus, CYP2D6/opioides, DPYD/fluoropirimidinas, TMPT/tiopurinas, CYP2D6/antidepresivos tricíclicos, CYP2C19/antidepresivos tricíclicos, NUDT15/tiopurinas, CYP2B6/efavirenz y CYP2C19/clopidogrel. En conclusión, aunque la contribución global de los países de ALC sigue siendo baja en el campo del PGx, se ha observado una mejora relevante en la región. La percepción de la utilidad de las pruebas PGx en la comunidad biomédica ha cambiado drásticamente, aumentando la concienciación entre los médicos, lo que sugiere un futuro prometedor en las aplicaciones clínicas de PGx en ALC.Pharmacogenomics (PGx) is considered an emergent field in developing countries. Research on PGx in the Latin American and the Caribbean (LAC) region remains scarce, with limited information in some populations. Thus, extrapolations are complicated, especially in mixed populations. In this paper, we reviewed and analyzed pharmacogenomic knowledge among the LAC scientific and clinical community and examined barriers to clinical application. We performed a search for publications and clinical trials in the field worldwide and evaluated the contribution of LAC. Next, we conducted a regional structured survey that evaluated a list of 14 potential barriers to the clinical implementation of biomarkers based on their importance. In addition, a paired list of 54 genes/drugs was analyzed to determine an association between biomarkers and response to genomic medicine. This survey was compared to a previous survey performed in 2014 to assess progress in the region. The search results indicated that Latin American and Caribbean countries have contributed 3.44% of the total publications and 2.45% of the PGx-related clinical trials worldwide thus far. A total of 106 professionals from 17 countries answered the survey. Six major groups of barriers were identified. Despite the region’s continuous efforts in the last decade, the primary barrier to PGx implementation in LAC remains the same, the “need for guidelines, processes, and protocols for the clinical application of pharmacogenetics/pharmacogenomics”. Cost-effectiveness issues are considered critical factors in the region. Items related to the reluctance of clinicians are currently less relevant. Based on the survey results, the highest ranked (96%–99%) gene/drug pairs perceived as important were CYP2D6/tamoxifen, CYP3A5/tacrolimus, CYP2D6/opioids, DPYD/fluoropyrimidines, TMPT/thiopurines, CYP2D6/tricyclic antidepressants, CYP2C19/tricyclic antidepressants, NUDT15/thiopurines, CYP2B6/efavirenz, and CYP2C19/clopidogrel. In conclusion, although the global contribution of LAC countries remains low in the PGx field, a relevant improvement has been observed in the region. The perception of the usefulness of PGx tests in biomedical community has drastically changed, raising awareness among physicians, which suggests a promising future in the clinical applications of PGx in LAC
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