Techno-economic evaluation and comparison of PAC-MBR and ozonation-UV revamping for organic micro-pollutants removal from urban reclaimed wastewater.

The presence of sewage-borne Organic Micro-Pollutants (OMP) in Wastewater Treatment Plants (WWTP) effluents represents an increasing concern when water is reclaimed for irrigation or even indirect potable reuse. During eighteen months, an innovative hybrid water reclamation scheme based on a Membrane Biological Reactor (MBR) enhanced with Powder Activated Carbon (PAC) was operated at pilot-scale (70 m3/d) in order to compare it with state-of-the art Wastewater Reclamation System (WWRS) also revamped with a final step of ozonation-UV. Removal of persistent OMP, water quality and treatment costs were evaluated and compared for the different treatment schemes. OMP removal efficiency results for the different schemes concluded that established technologies, such as physico-chemical and filtration systems as well as MBR, do not remove significantly (>15%) the most recalcitrant compounds. The upgrading of these two systems through the addition of ozonation-UV step and PAC dosing allowed improving average recalcitrant OMP removal to 85 ±â€¯2 and 75 ±â€¯5%, respectively. In term of costs, PAC-MBR represents an increase of 37% of costs regarding conventional systems but presents improvements of 50% reduction in space and water quality. On the other hand, ozonation requires up to a 15% increase of foot-print; nevertheless, represents lower costs and lower carbon footprint. Ozonation-UV seems to be the best option for upgrading existing facilities, while PAC-MBR should be considered when space represents a critical limitation and produced water is reused for high water quality purposes.

Evaluation of two aquatic passive sampling configurations for their suitability in the analysis of estrogens in water.

The presence of estrogens in the aquatic environment has been the target of several studies in the last decade. Newly developed passive sampling techniques for polar organic chemicals show great promise for the assessment of long-time exposure of aquatic organisms to emerging contaminants. In the present work, two configurations of the Chemcatcher(®) passive sampler have been tested for their applicability to the analysis of seven estrogens in water. Accumulation experiments in the laboratory, to calculate the uptake rates, and a field trial show that the polar configuration of this device may be used for the efficient sampling and determination of estrogens in water. Time weighted average concentrations were determined in the field trial and compared with spot sampling concentrations. The detection of estriol using passive sampling, although not found with spot sampling, clearly demonstrates the value of this technique in assessing relevant concentrations of estrogens in the aquatic media.

Evaluation of the aquatic passive sampler Chemcatcher for the monitoring of highly hydrophobic compounds in water.

The Chemcatcher passive sampler was primarily developed for the detection and quantification of priority organic pollutants (e.g., polycyclic aromatic hydrocarbons) in water. In the present study, this prototype was evaluated for highly hydrophobic compounds such as the tetrabrominated diphenyl ether BDE-47, the hexabrominated diphenyl ether BDE-153, and the historic pesticide DDT with its main metabolites (DDE and DDD). The sampling device consists basically of a receiving phase with high affinity for organic chemicals which is separated from the environment by a diffusion limiting membrane, both placed in a rigid PTFE body. C18 Empore disks were evaluated as receiving phase, obtaining a better accumulation when impregnated until saturation with n-octanol. As diffusion membrane, low density polyethylene was chosen over polyethersulphone. Once optimized its accumulation capacity for the target compounds, the linear behaviour of this accumulation was investigated and shown to be satisfactory in a period of 15 days. Preliminary uptake rates calculated from that accumulation anticipate the utility of this device for the detection of DDXs and the PBDEs, as calculated limits of detection are lower than usually reported environmental concentrations.

Evaluación, con una nueva escala de severidad, de la eficacia del tratamiento de las pseudoartrosis mediante campos electromagnéticos pulsátiles / Evaluation of the efficacy of treating pseudoarthrosis by pulsed electromagnetic fields with a new scale of fracture severity

Ciento cuarenta y seis fracturas con signos clínicos y radiológicos de falta de consolidación, tratadas mediante campos electromagnéticos pulsátiles han sido revisadas retrospectivamente. El objetivo de este estudio es conocer la influencia de la severidad de la fractura inicial y las características de la pseudoartrosis en la eficacia de este tratamiento. Para ello los autores han desarrollado una nueva escala cuantitativa que puntua diferentes variables clínicas y radiológicas previas al tratamiento. El resultado del tratamiento, la consolidación de la pseudoartrosis fue considerado al final del mismo. El éxito global del tratamiento con campos electromagnéticos pulsátiles fue del 71,2 %. El tiempo de evolución medio hasta el comienzo del tratamiento fue de 38,1 semanas. La severidad de la fractura inicial media según la escala fue de 11,64 puntos (5- 15 puntos). Las características de la pseudoartrosis puntuaron de media 11,1 puntos (6-18 puntos). Algunas características de la pseudoartrosis tienen influencia significativa en el resultado del tratamiento, mientras que la severidad incial de las fracturas no ha influido en los resultados. De acuerdo con nuestra escala los pacientes con pseudoartrosis que presentan puntuaciones inferiores a 10 puntos presentan un alto índice de curación con el tratamiento estudiado. Esto significa que en pacientes con pseudoartrosis estables e hipertróficas se debe considerar el tratamiento mediante campos electromagnéticos pulsátiles

One hundred forty-six fractures with clinical and radiologic signs of nonunion, treated by pulsed electromagnetic fields were studied retrospectively. The objective of the study is to know the influence of initial fracture severity and nonunion features in the efficacy of this treatment. The evaluation was based on our quantitative scale to evaluate and to quantify the severity of the initial fracture and the features of delayed union and nonunions before the treatment. The results were studied at the end of treatment considering the clinical and radiologic patterns of fracture healing. The average time from the initial fracture to the beginning of treatment was 38.1 weeks. The mean severity score was 11.64 points (range, 5 - 15 points) and the average of nonunion features was 11.1 points (range, 6 - 18 points). We found that some nonunion characteristics have a significant influence on the result of treatment, while the initial fracture severity does not. According to our scale, patients with nonunion who had scores of 10 points or less were prone to achieve healing. The overall success of treatment was 71.2%. In patients with stable and hypertrophic nonunions, pulsed electomagnetic fields must be one of the first treatment methods to consider

Importancia de los aplicadores de campo magnético en los tratamientos electroterapéuticos en las personas mayores / Importance of the magnetic field devices in electromagnetic therapy in the elderly

A medida que ha ido progresando el conocimiento sobre los mecanismos de interacción entre los campos magnéticos exógenos y el cuerpo humano se han ido incrementando sus aplicaciones terapéuticas, al mismo tiempo que se iban produciendo más eficientes y más especializados equipos y sistemas para aplicarlos. Los grandes avances que se consiguieron en traumatología y en rehabilitación dan paso a su empleo en el tratamiento de enfermedades degenerativas. Esta nueva indicación ha precisado modificaciones sustanciales en el diseño de los aplicadores con los que se genera el campo magnético en el que se sumerge al paciente durante cada sesión terapéutica. En el presente trabajo se revisan los conocimientos sobre la interacción campos magnéticos-organismos y los parámetros que regulan la interacción y sus efectos. Se describen los dos rangos de intensidad de los campos terapéuticos: a) campos del orden de militeslas (10-3 T), que tienen efectos sobre ciertos procesos metabólicos, regidos por las leyes de la fisicoquímica clásica, y b) campos extremadamente tenues, del orden de picoteslas (10-12 T), que actúan sobre ciertos procesos neuronales y que se rigen por las leyes de la física cuántica. Los primeros se utilizan en la corrección de fallos en la reparación ósea, mientras que los segundos están mostrando su eficiencia en el tratamiento de algunas enfermedades degenerativas, como la esclerosis múltiple o las enfermedades de Parkinson y de Alzheimer. Dado lo tenue de los campos con los que hay que actuar sobre el cerebro, resulta muy prometedora la posibilidad de aplicarlos en la modalidad de campos cruzados, por ser éste el modo de conseguir la máxima eficiencia (AU)

Enhancement of bone healing by an exogenous magnetic field and the magnetic vaccine.

We have demonstrated in rabbits that in the absence of a terrestial magnetic field, mammalian bone suffers from calcium depletion. This points to the possibility that the earth's field might be used as a 'magnetic vaccine' for the treatment of consolidation delays in bone healing. The effects, on bone calcification, of magnetic fields produced by electronically generated signals of sine and square waveform, over a range of frequencies from 0-250 kHz, were studied with the aid of a magnetic field generated within a coil containing the bone under test. Suggestions are made for an apparatus suitable for home use, and another which could be introduced into a hospital clinic.