Drug contamination from the perspective of higher education: University social responsibility experiences in Argentina and Chile

La presencia de fármacos o medicamentos en el medioambiente es un tema de preocupación global. Los medicamentos vencidos y/o en desuso domiciliario, no posibles de ser utilizados, deben gestionarse como residuos especiales o peligrosos (en virtud de la legislación vigente en cada jurisdicción), ya que su gestión inadecuada puede causar serios efectos negativos sanitarios y medioambientales. En los países de Latinoamérica la regulación asociada a este fenómeno es escasa. El objetivo de este trabajo fue abordar la problemática de la farmacontaminación mediante la presentación de dos experiencias exitosas, basadas en Gestión Posconsumo de Medicamentos, implementadas en el marco de programas de formación estudiantil en carreras de Farmacia de universidades latinoamericanas, como una modalidad de Responsabilidad Social Universitaria. A través de estas iniciativas se ofreció una alternativa transitoria de mitigación del impacto negativo en salud y ambiente del desecho inapropiado de los residuos farmacéuticos domiciliarios. Ambas experiencias latinoamericanas demostraron la importancia de fomentar la Responsabilidad Social Universitaria, como mecanismo de conexión de los estudiantes de nivel superior con el entorno social y la posibilidad de dar respuesta a problemáticas reales, como lo es la farmacontaminación.A presença de drogas ou medicamentos no meio ambiente é um tema de preocupação global. Esses medicamentos vencidos e/ou fora de uso em casa, que não podem ser consumidos, devem ser gerenciados como resíduos especiais ou perigosos (de acordo com a legislação vigente em cada jurisdição), pois o manejo inadequado pode causar graves efeitos negativos à saúde e ao meio ambiente. Nos países latino-americanos, a regulamentação associada a este fenómeno é escassa. O objetivo deste trabalho foi abordar o problema da contaminação de medicamentos apresentando duas experiências bem-sucedidas através de práticas de Gestão de Medicamentos Pós-Consumo, implementadas no âmbito de programas de formação de estudantes em duas especialidades de Farmácia de universidades latino-americanas como modalidade de Responsabilidade Social Universitária. Através destas iniciativas, foi oferecida uma alternativa temporária para mitigar o impacto negativo na saúde e no ambiente da eliminação inadequada de resíduos farmacêuticos domésticos. Ambas as experiências latino-americanas demonstram a importância de promover a Responsabilidade Social Universitária, como mecanismo de conexão dos estudantes de nível superior com o meio social e possibilidade de resposta a problemas reais, como a contaminação por drogas.Presence of drugs or medicines in the environment constitutes a global concern. Unused or expired medicines, which cannot be consumed, should be handled as special or hazardous waste (according to current legislation in each jurisdiction), given their potential to cause negative impacts on public and environmental health. In Latin American countries regulation in this regard is scarce. The objective of this work was to address the problem of drug contamination through the presentation of two successful experiences, based on Post-Consumption Drug Management, implemented within the framework of student training programs in Pharmacy careers at Latin American universities, as a modality of University Social Responsibility. Transitory responses were given through these initiatives in terms of mitigating the negative effects of unused/expired drug inappropriate disposal. Both examples demonstrate the importance of fostering social responsibility of universities as a connection mechanism between students and communities and also to provide response to real public health issues including drug-related pollution.Fil: González Vidal, Noelia Luján. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Sociedad Iberoamericana de Salud Ambiental; ArgentinaFil: Müller Ramirez, C.. Universidad de Concepción; Chil

Drug contamination from the perspective of higher education: University social responsibility experiences in Argentina and Chile

La presencia de fármacos o medicamentos en el medioambiente es un tema de preocupación global. Los medicamentos vencidos y/o en desuso domiciliario, no posibles de ser utilizados, deben gestionarse como residuos especiales o peligrosos (en virtud de la legislación vigente en cada jurisdicción), ya que su gestión inadecuada puede causar serios efectos negativos sanitarios y medioambientales. En los países de Latinoamérica la regulación asociada a este fenómeno es escasa. El objetivo de este trabajo fue abordar la problemática de la farmacontaminación mediante la presentación de dos experiencias exitosas, basadas en Gestión Posconsumo de Medicamentos, implementadas en el marco de programas de formación estudiantil en carreras de Farmacia de universidades latinoamericanas, como una modalidad de Responsabilidad Social Universitaria. A través de estas iniciativas se ofreció una alternativa transitoria de mitigación del impacto negativo en salud y ambiente del desecho inapropiado de los residuos farmacéuticos domiciliarios. Ambas experiencias latinoamericanas demostraron la importancia de fomentar la Responsabilidad Social Universitaria, como mecanismo de conexión de los estudiantes de nivel superior con el entorno social y la posibilidad de dar respuesta a problemáticas reales, como lo es la farmacontaminación.A presença de drogas ou medicamentos no meio ambiente é um tema de preocupação global. Esses medicamentos vencidos e/ou fora de uso em casa, que não podem ser consumidos, devem ser gerenciados como resíduos especiais ou perigosos (de acordo com a legislação vigente em cada jurisdição), pois o manejo inadequado pode causar graves efeitos negativos à saúde e ao meio ambiente. Nos países latino-americanos, a regulamentação associada a este fenómeno é escassa. O objetivo deste trabalho foi abordar o problema da contaminação de medicamentos apresentando duas experiências bem-sucedidas através de práticas de Gestão de Medicamentos Pós-Consumo, implementadas no âmbito de programas de formação de estudantes em duas especialidades de Farmácia de universidades latino-americanas como modalidade de Responsabilidade Social Universitária. Através destas iniciativas, foi oferecida uma alternativa temporária para mitigar o impacto negativo na saúde e no ambiente da eliminação inadequada de resíduos farmacêuticos domésticos. Ambas as experiências latino-americanas demonstram a importância de promover a Responsabilidade Social Universitária, como mecanismo de conexão dos estudantes de nível superior com o meio social e possibilidade de resposta a problemas reais, como a contaminação por drogas.Presence of drugs or medicines in the environment constitutes a global concern. Unused or expired medicines, which cannot be consumed, should be handled as special or hazardous waste (according to current legislation in each jurisdiction), given their potential to cause negative impacts on public and environmental health. In Latin American countries regulation in this regard is scarce. The objective of this work was to address the problem of drug contamination through the presentation of two successful experiences, based on Post-Consumption Drug Management, implemented within the framework of student training programs in Pharmacy careers at Latin American universities, as a modality of University Social Responsibility. Transitory responses were given through these initiatives in terms of mitigating the negative effects of unused/expired drug inappropriate disposal. Both examples demonstrate the importance of fostering social responsibility of universities as a connection mechanism between students and communities and also to provide response to real public health issues including drug-related pollution.Fil: González Vidal, Noelia Luján. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Sociedad Iberoamericana de Salud Ambiental; ArgentinaFil: Müller Ramirez, C.. Universidad de Concepción; Chil

Mid-infrared interferometry with K band fringe-tracking I. The VLTI MIDI+FSU experiment

Context: A turbulent atmosphere causes atmospheric piston variations leading to rapid changes in the optical path difference of an interferometer, which causes correlated flux losses. This leads to decreased sensitivity and accuracy in the correlated flux measurement. Aims: To stabilize the N band interferometric signal in MIDI (MID-infrared Interferometric instrument), we use an external fringe tracker working in K band, the so-called FSU-A (fringe sensor unit) of the PRIMA (Phase-Referenced Imaging and Micro-arcsecond Astrometry) facility at VLTI. We present measurements obtained using the newly commissioned and publicly offered MIDI+FSU-A mode. A first characterization of the fringe-tracking performance and resulting gains in the N band are presented. In addition, we demonstrate the possibility of using the FSU-A to measure visibilities in the K band. Methods: We analyzed FSU-A fringe track data of 43 individual observations covering different baselines and object K band magnitudes with respect to the fringe-tracking performance. The N band group delay and phase delay values could be predicted by computing the relative change in the differential water vapor column density from FSU-A data. Visibility measurements in the K band were carried out using a scanning mode of the FSU-A. Results: Using the FSU-A K band group delay and phase delay measurements, we were able to predict the corresponding N band values with high accuracy with residuals of less than 1 micrometer. This allows the coherent integration of the MIDI fringes of faint or resolved N band targets, respectively. With that method we could decrease the detection limit of correlated fluxes of MIDI down to 0.5 Jy (vs. 5 Jy without FSU-A) and 0.05 Jy (vs. 0.2 Jy without FSU-A) using the ATs and UTs, respectively. The K band visibilities could be measured with a precision down to ~2%.Comment: 11 pages, 13 figures, Accepted for publication in A&

Electronic structure and resistivity of the double exchange model

The double exchange (DE) model with quantum local spins S is studied; an equation of motion approach is used and decoupling approximations analogous to Hubbard's are made. Our approximate one-electron Green function G is exact in the atomic limit of zero bandwidth for all S and band filling n, and as n->0 reduces to a dynamical coherent potential approximation (CPA) due to Kubo; we regard our approximation as a many-body generalisation of Kubo's CPA. G is calculated self-consistently for general S in the paramagnetic state and for S=1/2 in a state of arbitrary magnetization. The electronic structure is investigated and four bands per spin are obtained centred on the atomic limit peaks of the spectral function. A resistivity formula appropriate to the model is derived from the Kubo formula and the paramagnetic state resistivity rho is calculated; insulating states are correctly obtained at n=0 and n=1 for strong Hund coupling. Our prediction for rho is much too small to be consistent with experiments on manganites so we agree with Millis et al that the bare DE model is inadequate. We show that the agreement with experiment obtained by Furukawa is due to his use of an unphysical density of states.Comment: 20 pages, 8 figures, submitted to J. Phys.: Condens. Matte

Monte Carlo Simulations for the Magnetic Phase Diagram of the Double Exchange Hamiltonian

We have used Monte Carlo simulation techniques to obtain the magnetic phase diagram of the double exchange Hamiltonian. We have found that the Berry's phase of the hopping amplitude has a negligible effect in the value of the magnetic critical temperature. To avoid finite size problems in our simulations we have also developed an approximated expression for the double exchange energy. This allows us to obtain the critical temperature for the ferromagnetic to paramagnetic transition more accurately. In our calculations we do not observe any strange behavior in the kinetic energy, chemical potential or electron density of states near the magnetic critical temperature. Therefore, we conclude that other effects, not included in the double exchange Hamiltonian, are needed to understand the metal-insulator transition which occurs in the manganites.Comment: 6 pages Revtex, 8 PS figure

A Cu2+ (S = 1/2) Kagom\'e Antiferromagnet: MgxCu4-x(OH)6Cl2

Spin-frustrated systems are one avenue for inducing macroscopic quantum states in materials. However, experimental realization of this goal has been difficult because of the lack of simple materials and, if available, the separation of the unusual magnetic properties arising from exotic magnetic states from behavior associated with chemical disorder, such as site mixing. Here we report the synthesis and magnetic properties of a new series of magnetically frustrated materials, MgxCu4-x(OH)6Cl2. Because of the substantially different ligand-field chemistry of Mg2+ and Cu2+, site disorder within the kagom\'e layers is minimized, as directly measured by X-ray diffraction. Our results reveal that many of the properties of these materials and related systems are not due to disorder of the magnetic lattice but rather reflect an unusual ground state.Comment: Accepted for publication in J. Am. Chem. Soc

Kondo-lattice model: Application to the temperature-dependent electronic structure of EuO(100) films

We present calculations for the temperature-dependent electronic structure and magnetic properties of thin ferromagnetic EuO films. The treatment is based on a combination of a multiband-Kondo lattice model with first-principles TB-LMTO band structure calculations. The method avoids the problem of double-counting of relevant interactions and takes into account the correct symmetry of the atomic orbitals. We discuss the temperature-dependent electronic structures of EuO(100) films in terms of quasiparticle densities of states and quasiparticle band structures. The Curie temperature T_C of the EuO films turns out to be strongly thickness-dependent, starting from a very low value = 15K for the monolayer and reaching the bulk value at about 25 layers

Argon annealing of the oxygen-isotope exchanged manganite La_{0.8}Ca_{0.2}MnO_{3+y}

We have resolved a controversial issue concerning the oxygen-isotope shift of the ferromagnetic transition temperature T_{C} in the manganite La_{0.8}Ca_{0.2}MnO_{3+y}. We show that the giant oxygen-isotope shift of T_C observed in the normal oxygen-isotope exchanged samples is indeed intrinsic, while a much smaller shift observed in the argon annealed samples is an artifact. The argon annealing causes the 18O sample to partially exchange back to the 16O isotope due to a small 16O contamination in the Ar gas. Such a contamination is commonly caused by the oxygen outgas that is trapped in the tubes, connectors and valves. The present results thus umambiguously demonstrate that the observed large oxygen isotope effect is an intrinsic property of manganites, and places an important constraint on the basic physics of these materials.Comment: 4 pages, 3 figures, submitted to PR

Conductance as a Function of the Temperature in the Double Exchange Model

We have used the Kubo formula to calculate the temperature dependence of the electrical conductance of the double exchange Hamiltonian. We average the conductance over an statistical ensemble of clusters, which are obtained by performing Monte Carlo simulations on the classical spin orientation of the double exchange Hamiltonian. We find that for electron concentrations bigger than 0.1, the system is metallic at all temperatures. In particular it is not observed any change in the temperature dependence of the resistivity near the magnetical critical temperature. The calculated resistivity near $T_c$ is around ten times smaller than the experimental value. We conclude that the double exchange model is not able to explain the metal to insulator transition which experimentally occurs at temperatures near the magnetic critical temperature.Comment: 6 pages, 5 figures included in the tex

Evolutionary-game-based dynamical tuning for multi-objective model predictive control

Model predictive control (MPC) is one of the most used optimization-based control strategies for large-scale systems, since this strategy allows to consider a large number of states and multi-objective cost functions in a straightforward way. One of the main issues in the design of multi-objective MPC controllers, which is the tuning of the weights associated to each objective in the cost function, is treated in this work. All the possible combinations of weights within the cost function affect the optimal result in a given Pareto front. Furthermore, when the system has time-varying parameters, e.g., periodic disturbances, the appropriate weight tuning might also vary over time. Moreover, taking into account the computational burden and the selected sampling time in the MPC controller design, the computation time to find a suitable tuning is limited. In this regard, the development of strategies to perform a dynamical tuning in function of the system conditions potentially improves the closed-loop performance. In order to adapt in a dynamical way the weights in the MPC multi-objective cost function, an evolutionary-game approach is proposed. This approach allows to vary the prioritization weights in the proper direction taking as a reference a desired region within the Pareto front. The proper direction for the prioritization is computed by only using the current system values, i.e., the current optimal control action and the measurement of the current states, which establish the system cost function over a certain point in the Pareto front. Finally, some simulations of a multi-objective MPC for a real multi-variable case study show a comparison between the system performance obtained with static and dynamical tuning.Peer ReviewedPostprint (author's final draft