34 research outputs found

    Calibración de Modelo Hidromecánico en Mezclas de Loess y Bentonita

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    Los suelos loessicos de la Ciudad de Córdoba, constituyen uno de los materiales más importantes empleados en obras de ingeniería especialmente en obras viales. Se han realizado importantes estudios investigando sus propiedades geotécnicas. En este trabajo, se realizaron ensayos de compresión no confinada y ensayos de infiltración mediante el empleo de un permeámetro a pared flexible. Se realizaron mezclas de suelo loessico con adición de bentonita en distintos porcentajes. Se evaluó el contenido de humedad, peso unitario seco y contenido de bentonita en las muestras remoldeadas. Se compararon los resultados obtenidos experimentalmente con los modelos propuestos mediante formulaciones matemáticas. Los resultados muestran que es posible lograr una aproximación entre el comportamiento hidromecánico teórico obtenido mediante la modelación y calibración de funciones racionales respecto del comportamiento empírico obtenido como resultado de ensayos en mezclas de suelo loessico estabilizadas con bentonita

    A 6 day course of liposomal amphotericin B in the treatment of infantile visceral leishmaniasis: the Italian experience

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    OBJECTIVES: To evaluate in a retrospective analysis the efficacy and safety of a 6 day course of liposomal amphotericin B (L-AmB) in infantile cases of Mediterranean visceral leishmaniasis (VL) diagnosed over a 10 year period in Italy. PATIENTS AND METHODS: Patients included were diagnosed as having VL consecutively admitted from December 1992 to December 2001 at four main referral children's hospitals in Italy and treated with six intravenous doses of 3 mg/kg L-AmB given on days 1-5 and 10 (a total dose of 18 mg/kg). Demographic data, nutritional status, underlying diseases, clinical and laboratory findings, and therapy outcome were considered. RESULTS: A total of 164 HIV-negative children (median age 1.6 years; range 4 months to 14 years) were enrolled. All patients were initially cured by the given treatment, and did not present adverse events related to drug infusion. Seven patients (4.3%) had a clinical and parasitological relapse 3-15 months after therapy. All relapses were successfully retreated with 3 mg/kg L-AmB for 10 consecutive days (a total dose of 30 mg/kg). CONCLUSIONS: This study highlights the efficacy (>95%) and safety of the six dose L-AmB regimen and validates it as a first-line treatment for Mediterranean VL in children

    Application of evidence-based methods to construct mechanism-driven chemical assessment frameworks

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    The workshop titled “Application of evidence-based methods to construct mechanism-driven chemical assessment frameworks” was co-organized by the Evidence-based Toxicology Collaboration and the European Food Safety Authority (EFSA) and hosted by EFSA at its headquarters in Parma, Italy on October 2 and 3, 2019. The goal was to explore integration of systematic review with mechanistic evidence evaluation. Participants were invited to work on concrete products to advance the exploration of how evidence-based approaches can support the development and application of adverse outcome pathways (AOP) in chemical risk assessment. The workshop discussions were centered around three related themes: 1) assessing certainty in AOPs, 2) literature-based AOP development, and 3) integrating certainty in AOPs and non-animal evidence into decision frameworks. Several challenges, mostly related to methodology, were identified and largely determined the workshop recommendations. The workshop recommendations included the comparison and potential alignment of processes used to develop AOP and systematic review methodology, including the translation of vocabulary of evidence-based methods to AOP and vice versa, the development and improvement of evidence mapping and text mining methods and tools, as well as a call for a fundamental change in chemical risk and uncertainty assessment methodology if to be conducted based on AOPs and new approach methodologies (NAM). The usefulness of evidence-based approaches for mechanism-based chemical risk assessments was stressed, particularly the potential contribution of the rigor and transparency inherent to such approaches in building stakeholders’ trust for implementation of NAM evidence and AOPs into chemical risk assessment

    Calibración de Modelo Hidromecánico en Mezclas de Loess y Bentonita

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    This paper analyzes the implementation of a software tool based on fuzzy logic to identify the sustainable location of four industrial parks in the province of Córdoba.Being the location study of multiple solutions, there may be more than one possible location that can make the project sustainable.Primarily the software on which this study is based is the Expert Choice V11 that uses the Analytic Hierarchy Process (AHP). The APH combines human perception, preferences and experience to prioritize options in complex situations such as those presented in this paper.After applying the software in localization studies could assess its usefulness and the strengths as decision support for the location of industrial parks..Los suelos loessicos de la Ciudad de Córdoba, constituyen uno de los materiales más importantes empleados en obras de ingeniería especialmente en obras viales. Se han realizado importantes estudios investigando sus propiedades geotécnicas. En este trabajo, se realizaron ensayos de compresión no confinada y ensayos de infiltración mediante el empleo de un permeámetro a pared flexible. Se realizaron mezclas de suelo loessico con adición de bentonita en distintos porcentajes. Se evaluó el contenido de humedad, peso unitario seco y contenido de bentonita en las muestras remoldeadas. Se compararon los resultados obtenidos experimentalmente con los modelos propuestos mediante formulaciones matemáticas. Los resultados muestran que es posible lograr una aproximación entre el comportamiento hidromecánico teórico obtenido mediante la modelación y calibración de funciones racionales respecto del comportamiento empírico obtenido como resultado de ensayos en mezclas de suelo loessico estabilizadas con bentonita

    Magnetic properties and EPR spectra of [Cu(L-arginine)2](NO3)2.3H2O

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    Magnetic and EPR data have been collected for complex [Cu(L-Arg)2](NO3)2-3H2O (Arg ¼ arginine). Magnetic susceptibility w in the temperature range 2–160 K, and a magnetization isotherm at T ¼ 2.29(1)K with magnetic fields between 0 and 9 T were measured. The observed variation of wT with T indicates predominant antiferromagnetic interactions between Cu(II) ions coupled in 1D chains along the b axis. Fitting a molecular field model to the susceptibility data allows to evaluate g ¼ 2.10(1) for the average g-factor and J ¼ -0.42(6) cm-1 for the nearest neighbor exchange coupling (defined as Hex ¼ -PJijSi- Sj). This coupling is assigned to syn–anti equatorial–apical carboxylate bridges connecting Cu(II) ion neighbors at 5.682A ° , with a total bond length of 6.989A ° and is consistent with the magnetization isotherm results. It is discussed and compared with couplings observed in other compounds with similar exchange bridges. EPR spectra at 9.77 were obtained in powder samples and at 9.77 and at 34.1GHz in the three orthogonal planes of single crystals. At both microwave frequencies, and for all magnetic field orientations a single signal arising from the collapse due to exchange interaction of resonances corresponding to two rotated Cu(II) sites is observed. From the EPR results the molecular g-tensors corresponding to the two copper sites in the unit cell were evaluated, allowing an estimated lower limit |J |40.1 cm-1 for the exchange interaction between Cu(II) neighbors, consistent with the magnetic measurements.Fil: Gerard, Matias Fernando. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Aiassa, C.. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Casado, Nieves Maria Claudia. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Santana, R. C.. Universidade Federal de Goiás; BrasilFil: Perec, Mireille. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rapp, R. E.. Universidade Federal do Rio de Janeiro; BrasilFil: Calvo, Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin
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