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El lixiviado de relleno sanitario (LX), es un líquido con un gran potencial eco-toxicológico que se genera como producto de la mezcla de agua lluvia que percola por el relleno y tiene contacto con el residuo sólido (RS) allí depositado, agua producida de la biodegradación de los residuos y el agua propia que contienen los residuos. El uso de eco-tecnologías (humedales construidos, lagunas algales) por las grandes ventajas ecológicas y ambientales exhibidas, han comenzado a emplearse en el tratamiento de LX con resultados bastante alentadores. En este sentido, la presente investigación desarrollada en el relleno sanitario de Presidente, municipio de San Pedro, Valle del Cauca, Colombia en el 2015, estuvo orientada a evaluar a escala piloto el uso del acople eco-tecnológico Biorreactor Laguna Anaerobia de Alta Tasa BLAAT® + humedal construido (HC) sembrado con policultivos de las especies tropicales Colocasia esculenta-Ce, Heliconia psittacorum-He y Gynerium sagittatum-Gs, para el tratamiento de LX bajo condiciones del trópico americano. Este trabajo coloca a disposición una serie de datos de campo sobre la calidad del lixiviado crudo y del efluente de cada unidad de tratamiento, mostrando el desempeño del acople, lo que puede contribuir al establecimiento de condiciones y escenarios para el tratamiento de este en poblaciones que dispongan condiciones cultural y ambiental similares a la zona del presente estudio.

The structural and critical exponent analysis along with the universal behavior of the magnetocaloric effect in nano-crystalline La0.7Ca0.3Mn1−xNixO3 (x = 0.0, 0.02, 0.07, 0.10), manganites, exhibiting second order phase transition, are experimentally studied. Structural study using Rietveld refinement of X-ray diffraction patterns shows orthorhombic structure with Pnma space group. The Curie temperature could be tuned over a wide temperature range upon variation in the Ni2+ content. The nature of the transition was found to be of second order for all Ni2+-concentrations. Various techniques such as modified Arrott plots, Kouvel-Fisher method and critical isotherm were used to analyze the magnetic-field dependence of magnetization. Although the critical exponents beta (β), gamma (γ) and delta (δ) were analyzed with various theoretical models such as 3D-Ising model and 3D-Heisenberg model, the estimated critical exponents, obtained for different values of X, seemed to be consistent with those predicted by the mean-field theory. The critical exponents were further confirmed using the single scaling equation M(H,e) = eβf ± (H/eγ+β). The achieved results indicated that the obtained values of the critical exponents were reliable and reasonably accurate.

Nanosized La0.7Ca0.3Mn1-xNixO3 (x = 0, 0.02) manganites were synthesized via the auto-combustion method. The critical behavior of these samples was then carefully investigated by analyzing the results of static magnetic measurements near their critical temperatures. The samples exhibited second-order phase transition, and the effect of Ni doping was to lower the critical temperature. The analysis of the experimental data was carried out by means of various techniques, such as modified Arrott plots, the Kouvel-Fisher method, and critical isotherm analysis, which revealed that the values of the critical exponents β, γ, and δ are close to those theoretically predicted by mean-field theory. By using the Widom scaling relation and the universal scaling hypothesis, the dependability of the obtained values of the critical exponents was confirmed. Moreover, the temperature dependence of the spontaneous magnetization was estimated from the analysis of the variation of the magnetic entropy change with the magnetization within the framework of mean-field theory. Interestingly, the spontaneous magnetization determined from the entropy change and that obtained from classical extrapolation of the Arrott curves displayed high concordance. These results strongly suggested that the interactions among spins in the investigated compound are long-range.

This study evaluated the capacity of a pilot-scale high-rate algal pond (HRAP) to remove pharmaceutical compounds (PCs) from domestic wastewater in the city of Santiago de Cali, Colombia. The compounds analyzed included antiepileptics, hypolipidemic drugs, tranquilizers and analgesics, and anti-inflammatory drugs. The HRAP operated under a continuous water flow of 0.2 m3d−1 and a 3-day hydraulic retention time (HRT). Removal efficiencies were high (>70%) for fenofibric acid, ibuprofen, and paracetamol; medium (30–70%) for gabapentin, lamotrigine, fenofibrate, gemfibrozil, diclofenac, ketoprofen, naproxen, and pentoxifylline; and low (50%) in the ecological hazard posed by most of the compounds, although it is important to note that the hazard from gemfibrozil and ibuprofen remained high even after treatment, indicating the need for complementary treatment.

Los microcontaminantes incluyen una amplia gama de compuestos presentes en el ambiente en concentraciones de µg/L o ng/L. En este estudio se analizo la presencia y concentracion de microcontaminantes como compuestos farmaceuticos y disruptores endocrinos en el ciclo urbano del agua de la ciudad de Santiago de Cali, Colombia, donde se incluyeron cuatro puntos de monitoreo de agua superficial, tres de agua potable y uno de agua residual. Se realizaron cinco jornadas de muestr eo: un muestreo preliminar en el cual se cuantificaron 92 compuestos clasificados en cinco grupos de compuestos farmaceuticos (I, II, III, IV y V) y un grupo de disruptores endocrinos (DE), a partir del cual se priorizaron tres grupos a ser determinados en los cuatro muestreos siguientes. Los criterios de presencia, concentracion, efectos sobre la biota acuatica y financiamiento de la investigacion, se emplearon para seleccionar los grupos I, IV y DE, los cuales tuvieron una presencia superior al 48 % y una concentracion media de hasta 11 000 ng/L. Se encontro que los compuestos mas relevantes, en terminos de presen cia y concentracion en el ciclo urbano del agua fueron 10,11-dihydro-10,11-dihidroxicarbamazepina, ibuprofeno, naproxeno, gemfibrozilo, paracetamol, sulfametoxazol, estronas, 4-iso-nonilfenol y bisfenol A. La presencia en el ciclo urbano del agua de Cali genera una alerta por la potencial amenaza sobre los organismos acuaticos y la salud humana.

Endocrine disruptors have been studied for their high occurrence in different environments including aquatic; however, in the context of developing countries, their occurrence, magnitude and potential threat have little information. This study involved the analysis of various components of the urban water cycle in the city of Bogota, Colombia. As a result, it was found that the compounds with the highest occurrence are plasticizers such as phthalates and bisphenol A, whereas among the drugs, carbamazepine presented the highest concentrations (0.68-31.45 µg L-1); the analysis of the threat coefficient (HQ) showed the importance of bis(2-ethylhexyl) phthalate (BEHP) and estrone (E1) that can reach surface waters from domestic and industrial discharges.

Water pollution due to human activities produces sedimentation, excessive nutrients, and toxic chemicals, and this, in turn, has an effect on the normal endocrine functioning of living beings. Overall, water pollution may affect some components of the fitness of organisms (e.g., developmental time and fertility). Some toxic compounds found in polluted waters are known as endocrine disruptors (ED), and among these are nonhalogenated phenolic chemicals such as bisphenol A and nonylphenol. To evaluate the effect of nonhalogenated phenolic chemicals on the endocrine system, we subjected two generations (F0 and F1) of Drosophila melanogaster to different concentrations of ED. Specifically, treatments involved wastewater, which had the highest level of ED (bisphenol A and nonylphenol) and treated wastewater from a constructed Heliconia psittacorum wetland with horizontal subsurface water flow (He); the treated wastewater was the treatment with the lowest level of ED. We evaluated the development time from egg to pupa and from pupa to adult as well as fertility. The results show that for individuals exposed to treated wastewater, the developmental time from egg to pupae was shorter in individuals of the F1 generation than in the F0 generation. Additionally, the time from pupae to adult was longer for flies growing in the H. psittacorum treated wastewater. Furthermore, fertility was lower in the F1 generation than in the F0 generation. Although different concentrations of bisphenol A and nonylphenol had no significant effect on the components of fitness of D. melanogaster (developmental time and fertility), there was a trend across generations, likely as a result of selection imposed on the flies. It is possible that the flies developed different strategies to avoid the effects of the various environmental stressors.

It has been recognized that numerous synthetic compounds like Bisphenol A (BPA) and nonylphenols (NP) are present in effluents from wastewater treatment plants (WWTP) at levels of parts per billion (μg L(-1)) or even parts per trillion (ng L(-1)) with a high potential to cause endocrine disruption in the aquatic environment. Constructed wetlands (CW) are a cost-effective wastewater treatment alternative with promising performance to treat these afore mentioned compounds. This research was aimed to evaluate the efficacy of CW treatment of WWTP effluent for mitigating the effects endocrine disrupting compounds (EDCs). This research goal was accomplished by (1) quantifying the removal of BPA and NP in CWs; (2) isolating CW fungal strains and testing for laccase production; and (3) performing endocrine disruption (reproduction) bioassays using the fruit fly Drosophila melanogaster. Three pilot scale horizontal subsurface flow constructed wetlands (HSSF-CW) were operated for eight weeks: one planted with Phragmites australis; one planted with Heliconia psitacorum; and one unplanted. The Heliconia CW showed a removal efficiency of 73.3(± 19%) and 62.8(± 20.1%) for BPA and NP, respectively; while the Phragmites CW demonstrated a similar removal for BPA (70.2 ± 27%) and lower removal efficiency for NP 52.1(± 37.1%).The unplanted CW achieved 62.2 (± 33%) removal for BPA and 25.3(± 37%) removal for NP. Four of the eleven fungal strains isolated from the Heliconia-CW showed the capacity to produce laccase. Even though complete removal of EDCs was not achieved by the CWs, the bioassay confirmed a significant improvement (p < 0.05) in fly viability for all CWs, with Heliconia sp. being the most effective at mitigating adverse effects on first and second generational reproduction. This study showed that a CW planted with a native Heliconia sp. CW demonstrated a higher removal of endocrine disrupting compounds and better mitigation of reproductive disruption in the bioassay.

The presence of pharmaceutical compounds in aquatic ecosystems may affect both biota and human health because these micropollutants are capable of altering the metabolism and reproduction capacity of the live organisms of the aquatic ecosystems. The main route of entry of these pollutants into the aquatic environment is through Wastewater Treatment Plants (WWTPs) effluents. Compounds such as diclofenac (DCF) and carbamazepine (CBZ) persist, undergoing little or no degradation during treatment. Coupled systems combining biological treatments and Advanced Oxidation Technologies (AOTs) represent an alternative to reduce the risk of the presence of pharmaceuticals in the environment by achieving high removal efficiency at a low cost. This research evaluated the performance of a coupled system integrated by Horizontal Subsurface Flow Constructed Wetland (CW HSSF) and Solar Photo-Fenton at laboratory scale under America tropical conditions for the removal of DCF and CBZ from domestic wastewater at 15 μg L−1, on average. Three Fe2 +/H2O2 ratios (0.1, 0.3, and 0.8) were tested. Concentrations of DCF, CBZ, organic matter (DOC), Total Nitrogen (TN), and in situ variables were measured throughout the experiment. Removal efficiencies up to 92% and 86% were achieved for DCF and CBZ, respectively, using the Fe2+/H2O2 ratio of 0.1. There were no significant differences between the Fe2+/H2O2 ratios used (p

Se evaluó la presencia de compuestos farmacéuticos de los grupos terapéuticos antiepilépticos, agentes hipolipemiantes, analgésicos antiinflamatorios y tranquilizantes en tres jornadas de muestreo, además se estimó la eficiencia de eliminación mediante un tratamiento primario avanzado (TPA) con procesos de coagulación, floculación y sedimentación en la planta de tratamiento de agua residual de la ciudad de Cali (Colombia). De los compuestos medidos, 10 estuvieron por encima del límite de detección de la técnica analítica usada: carbamazepina, 10,11-Dihidro-10,11-dihidroxicarbamazepina, gabapentina, ácido fenofíbrico, gemfibrozilo, diclofenaco, ibuprofeno, ketoprofeno, naproxeno y paracetamol, en concentraciones que oscilaron entre 0.15 y 10 µgL-1 en el afluente. Después del tratamiento, la mayoría de compuestos tuvieron eficiencias de eliminación inferiores al 30%, siendo el paracetamol y naproxeno los que obtuvieron los mejores porcentajes de 98.1 y 57.1%, respectivamente. Estas eficiencias de eliminación se relacionaron no solo al proceso de coagulación floculación, el cual es favorable para compuestos lipofílicos, sino también a la biodegradación por la acción de las bacterias presentes en la matriz de agua residual.

In recent years, constructed wetlands have been widely used for the purification of wastewater, representing an alternative method that offers multiple advantages when compared to other treatment systems. The present study assessed the efficiency of six horizontal subsurface flow constructed wetlands (HSSFCW) at pilot scale for the removal of organic matter (COD), nutrients (N-NO3-, P-PO43-) and lead (Pb2+). The study also looked at the operating time on hydraulic conductivity (Ks) to treat leachate from the “El Ojito” Sanitary Landfill in the municipality of Popayán, Cauca. Three wetlands were planted with Heliconia psittacorum (HSSFCW-H. p), and three with Cyperus haspan (HSSFCW-C. h). The support medium used was gravel. They were operated at a flow of 0.012m3/day, and a hydraulic retention time of 4 days. The units received effluent from the oxidation pond. The results showed mean removals of COD (51.67 and 64.00%), N-NO3- (45.33 and 48.17%), P-PO43- (53.67 and 62.67%) and Pb+2 (5.74 and 14.75%) for HSSFCW-H. p and HSSFCW-C. h respectively. Hydraulic conductivity values were between 700 and 1000m/day. The wetland system proved to be efficient for the secondary treatment of leachate from mature landfills, obtaining removal efficiencies significantly higher in HSSFCW-C. h. Los humedales construidos en los últimos años han sido ampliamente usados en la depuración de una gran variedad de aguas residuales, por ser una alternativa que ofrece múltiples ventajas, en comparación con otros sistemas de tratamiento. Este estudio evaluó la eficiencia de seis sistemas de humedales, construidos de flujo subsuperficial horizontal (HCFSSH), a escala piloto, para la remoción de materia orgánica (DQO), nutrientes (N-NO3-, P-PO43-) y plomo (Pb+2), además de la incidencia del tiempo de operación sobre la conductividad hidráulica (Ks) para tratar lixiviados del Relleno Sanitario “El Ojito”, del municipio de Popayán, Cauca. Tres humedales fueron plantados con Heliconia psittacorum (HCFSSH-H. p) y tres con Cyperus haspan (HCFSSH-C. h); el medio de soporte utilizado fue grava, operados con un caudal de 0.012m3/día y un tiempo de retención hidráulico de 4 días; las unidades recibieron efluente de una laguna de oxidación. Los resultados mostraron remociones medias de: DQO (51,67 y 64,00%), N-NO3- (45,33 y 48,17%), P-PO43- (53,67 y 62,67%) y Pb+2 (5,74 y 14,75%) para los HCFSSH-H. p y HCFSSH-C. h, respectivamente y valores de conductividad hidráulica, entre 700 y 1000m/día. El sistema de humedales mostró ser eficiente para el tratamiento secundario de lixiviado de rellenos sanitarios maduros, obteniendo eficiencias de remoción, significativamente mayores, en los HCFSSH-C. h. Incluye referencias bibliográficas

Este estudio tuvo como objetivo estimar el potencial impacto en los atributos químicos y macronutricionales de un suelo inceptisol sembrado con caña de azúcar y sometido a tres diferentes tratamientos de riego: Efluente de la PTAR-C (T1), Agua de Pozo (T2) y Agua de Pozo más fertilización química (T3). Se instaló un experimento en bloques completos al alzar con parcelas divididas con tres repeticiones. Al final del estudio se encontró que las relaciones de bases químicas (Ca/Mg, Mg/K, Ca+Mg/K) mejoraron en todas las parcelas, en todos los tratamientos, situación que se ratifica al no encontrarse diferencias estadísticas significativas entre los tratamientos. Así mismo, se encontró que el tipo de tratamiento no influyó en la variación en los contenidos de los macronutrientes (N, P, K) del suelo. Los contenidos de materia orgánica, P, Na y K aumentaron; y disminuyeron los de nitrógeno inorgánico(N-NH , N-NO ) independientemente del tratamiento, lo que permite inferir la no asociación de impactos adversos4 3en el suelo por el reúso de agua residual tratada en riego de caña de azúcar.

Introduction: As a consequence of population isolation by the presence of geomorphological barriers, dolphins from northern South America are subdivided into three species: I. geoffrensis (Amazon and Orinoco Rivers), I. boliviensis (Madeira River in Bolivia), and the recently described I. araguaiaensis inhabiting the hydrologic complex of the Araguaia –Tocantins Rivers in the northeastern Brazilian Amazon. The importance of pink dolphins at the ecosystems they inhabit is supported by: 1) its position as top predators in the food chain; 2) bioindicators for ecosystem health; 3) its cultural and mythological meaning for the local ethnic groups, such as Sikuanis from the Orinoco, and Ticuna for the Amazon; and 4) their economic value, mainly as a touristic attraction. The conservation status of Orinoquian populations of river dolphins ( i. g. humboldtiana ), has not been fully established. However, we know their populations are threatened by a series of human activities on both aquatic and terrestrial environments, affecting their occurrence across the basin. This research is part of an inter-institutional effort conducted between the Corporacion para el Desarrollo Sostenible del Area de Manejo Especial de la Macarena (CORMACARENA) and Fundacion Omacha, to monitor pink dolphin populations inhabiting the rivers: Meta, Manacacias, Yucao, and Cusiana, in order to identify conservation tensors affecting the species in the study area. Methods: We conducted a multitemporal study to determine anthropogenic threats affecting dolphin populations during two hydrologic periods along 317.2 km -1 across the middle Meta River basin. We calculated the degradation index for streams of continental waters and density of the river dolphins, developed by Gomez-Salazar et al. (2012). Water quality, habitat transformation, species exploitation, and the increment in number of human settlements were identified as the main conservation tensors in the analyzed area. Results: We obtained a high value in the index of degradation, with a potential increment in value through time. River confluences were identified as priority areas for the conservation of the species. The development of infrastructure projects on the main streams was identified as a future threat on freshwater ecosystems in the basin. Differences in hydrologic periods were identified as an important variable, not only affecting the ecological dynamic of the species, but also determining the anthropogenic tensors through time. Water quality, habitat modification, and species exploitation were particularly intense at low water level periods, while boat traffic, and fishing activities are more frequent at periods of high water levels in the region. Discussion and conclusions: For the Meta River, water quality and species exploitation appear to be the major tensors for dolphins and they may explain the low densities recorded for the area in comparison with densities reported for the Amazon basin. Even though, we consider this analysis is not definite and more samplings are necessary to confirm this hypothesis. Finally, river confluences were identified as conservation hot spots for dolphin populations. We point out on the importance of river dolphins as umbrella species, ideal to develop conservation strategies in the region. Key words: Degradation index, Meta River, threats and conservation, Tonina.

Sanitary landfills are the most widely used method of solid waste disposal around the world. Landfill leachate (LL) is recognized as one of the most critical issues for landfill operators. Landfill leachate may contain large amounts of organic matter (biodegradable, and refractory to biodegradation), as well as ammonia-nitrogen, heavy metals (HM) and chlorinated organic and inorganic salts. Various landfill leachate treatment technologies have been broadly used, including biological processes (aerobic, anaerobic and anoxic) and physicochemical processes (oxidation, precipitation, coagulation/flocculation, ozonation, activated carbon adsorption, electrochemical oxidation, Fenton process, membrane filtration). Constructed wetlands are classified among the biological methods that use phytoremediation for polluted liquid treatment. They are defined as engineered systems that use natural processes (vegetation, soils and microorganisms) to remove, transform and degrade pollutants from wastewater, creating an efficient synergic effect. The effectiveness of constructed wetlands for landfill leachate treatment has been extensively demonstrated and its full-scale implementation is rising among regions given its adaptability and capacity to efficiently treat landfill leachate.

Magnetometry measurements performed on TbMnO $$_{3}$$ films grown onto single-crystal [001] SrTiO $$_{3}$$ substrates using magnetron sputtering technique exhibit series of anomalies related to the magnetic ordering of the Mn $$^{3+}$$ sublattice. Despite the fact that bulk TbMnO $$_{3}$$ is a low-temperature antiferromagnet, the measurements indicate the presence of high-temperature ferromagnetism. Well-defined hysteresis loops are observed at temperatures as high as 70 K. Analysis of the X-ray diffraction patterns of the target and films shows no evidence of affectation (within the resolution limit of the technique) by external impurities, such as Mn $$_{3}$$ O $$_{4}$$ , which might give rise to an artificial magnetic signal. Thus, it is probable that the ferromagnetism observed in the films to be an intrinsic property of TbMnO $$_{3}$$ . Concretely, it is possible that the strain imposed by the substrate, resulting in the tetragonally distorted orthorhombic phase of the TbMnO $$_{3}$$ films, is behind the mechanism governing the anomalous ferromagnetism observed in the films.

Four subsurface horizontal-flow constructed wetlands (CWs) at a pilot scale planted with a polyculture of the tropical plants Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) were evaluated for 7 months. The CW cells with an area of 17.94 m2 and 0.60 m (h) each and 0.5 m of gravel were operated at continuous gravity flow (Q = 0.5 m3 day−1) and a theoretical HRT of 7 days each and treating landfill leachate for the removal of filtered chemical oxygen demand (CODf), BOD5, TKN, NH4 +, NO3 −, PO4 3−–P and Cr(VI). Three CWs were divided into three sections, and each section (5.98 m2) was seeded with 36 cuttings of each species (plant density of six cuttings per square metre). The other unit was planted randomly. The final distributions of plants in the bioreactors were as follows: CW I (He-Ce-Gs), CW II (randomly), CW III (Ce-Gs-He) and CW IV (Gs-He-Ce). The units received effluent from a high-rate anaerobic pond (BLAAT®). The results show a slightly alkaline and anoxic environment in the solid-liquid matrix (pH = 8.0; 0.5–2 mg L−1 dissolved oxygen (DO)). CODf removal was 67 %, BOD5 80 %, and TKN and NH4 + 50–57 %; NO3 − effluents were slightly higher than the influent, PO4 3−–P (38 %) and Cr(VI) between 50 and 58 %. CW IV gave the best performance, indicating that plant distribution may affect the removal capacity of the bioreactors. He and Gs were the plants exhibiting a translocation factor (TF) of Cr(VI) >1. The evaluated plants demonstrated their suitability for phytoremediation of landfill leachate, and all of them can be categorized as Cr(VI) accumulators. The CWs also showed that they could be a low-cost operation as a secondary system for treatment of intermediated landfill leachate (LL).

This study assessed the accumulation of Cd (II), Hg (II), Cr (VI) and Pb (II) in Gynerium sagittatum (Gs), Colocasia esculenta (Ce) and Heliconia psittacorum (He) planted in constructed wetlands treating synthetic landfill leachate. Sixteen bioreactors were operated in two experimental blocks. Metal concentrations in the influent and effluent; root, stem, branch and leaves of plants were analysed, as well as COD, N-NH4+, TKN, T, pH, ORP, DO, and EC. Average removal efficiencies of COD, TKN and NH4+-N were 66, 67 and 72%, respectively and heavy metal removal ranged from 92 to 98% in all units. Cr (VI) was not detected in any effluent sample. The bioconcentration factors (BCF) were 10(0) -10(2). The BCF of Cr (VI) was the lowest: 0.59 and 2.5 (L kg(-1)) for Gs and He respectively; whilst Cd (II) had the highest (130-135 L kg(-1)) for Gs. Roots showed a higher metal content than shoots. Translocation factors (TF) were lower, He was the plant exhibiting TFs1 for Pb (II), Cr (T) and Hg (II) and 0.4-0.9 for Cd (II) and Cr (VI). The evaluated plants demonstrate their suitability for phytoremediation of landfill leachate and all of them can be categorized as metals accumulators.

RESUMEN. Los sistemas algales de alta tasa fotosintética se caracterizan por la mejora en el crecimiento de la biomasa y capacidad de tratamiento de lixiviados. Las microalgas involucradas en estos sistemas son utilizadas para la biorremediación de contaminantes, y también pueden indicar cambios en el sistema acuático al presentar variaciones en la estructura y crecimiento de las comunidades. Este estudio tuvo como objetivo evaluar la diversidad de la comunidad de algas asociadas a un sistema algal de alta tasa fotosintética empleado en la biorremediación del lixiviado del relleno de San Pedro, Valle del Cauca, Colombia. Para ello se tomaron muestras biológicas y medición de parámetros físicos y químicos durante tres fases del tratamiento entre noviembre 2012 y julio 2013. Se utilizaron los índices de Shannon y Simpson para evaluar la diversidad del sistema. En total se registraron 28 especies, siendo Chilomonas insignis y Euglena sp. 1 las más abundantes. El estudio reveló variaciones tanto en abundancia como en composición de especies durante todas las fases de desarrollo del sistema. En la primera fase dominaron individuos del phylum Cryptophyta y en la segunda y tercera, individuos del phylum Euglenophyta. La dominancia de los individuos estuvo asociada a la concentración de compuestos orgánicos y nutrientes en el agua. Los índices mostraron una baja diversidad (entre 0 y 2), siendo la segunda fase el momento de mayor diversidad (H' = 1,77). Finalmente, el conocimiento de la estructura y dinámica del fitoplancton es clave para el mantenimiento y desempeño de este sistema.

In this work the study of viscosity is presented for a magnetorheological fluid made from iron oxides micrometre, under an external magnetic field. The material was characterized by magnetic loops in a vibrating sample magnetometer and its crystal structure by X-ray diffraction. The results show that saturation magnetization and coercive field have dependence with the powder size. The material has different crystal structure which lattice parameters were determined by Rietveld refinement. The viscosity of the magnetorheological fluid was measured by a viscometer with rotational symmetry with and without external field. This result evidence a dependency on the size, percentage iron oxide and the applied magnetic field, it is due to the hydrodynamic volume of iron oxide interacts with the external magnetic field, increasing the flow resistance.

Introduction and objectives: Hemorrhagic cystitis (HC) after pelvic radiotherapy occurs in 2-8% of patients. A variety of treatments have been described, most of them with uncertain results. We assessed the efficacy of hyperbaric oxygen therapy (HBOt) in HC cases. Patients and methods: retrospective analysis of patients with HC after pelvic radiotherapy receiving HBOt at our center between January 2002 and January 2010. Our protocol included 40 sessions of HBOt in a multiplace hyperbaric chamber with 90minutes of 100% oxygen breathing at 2.2 atm. Success was evaluated in terms of total or partial stop of bladder bleeding. telephone follow-up was updated at the time of submission in all cases. Results: twenty-five patients were treated (21 male, 4 female); the mean age was 66.7 years. twenty men were irradiated for prostate cancer and one for bladder cancer. three

A systematic study of the dependence of the magnetization on the magnetic field around the ferromagnetic–paramagnetic phase transition temperature is carried out on La0.7Ca0.3Mn1-xNixO3 (x=0, 0.02, 0.07, and 1) samples synthesized by auto-combustion method. The successful substitution of Mn3+ ions by Ni2+ ions in the La0.7Ca0.3MnO3 lattice is corroborated by X-ray diffraction technique. Banerjees criteria, Arrott plots, and the scaling hypothesis are used to analyze the experimental data. It is verified that the Ni-doping increases the operating temperature range for magnetocaloric effect through tuning of the magnetic transition temperature. Probably, the replacement of Mn3+ by Ni2+ ions in the La0.7Ca0.3MnO3 lattice weakens the Mn3+-O-Mn4+ double exchange interaction, which leads to a decrease in the transition temperature and magnetic moment in the samples. The Arrott plots suggest that the phase transition from ferromagnetic to paramagnetic in the nano-sized manganite is of second order. The analysis of the magnetization results show that the maximum magnetic entropy changes observed for x=0, 0.02, 0.07, and 0.1 compositions are 0.85, 0.77, 0.63, and 0.59 J/kg K, under a magnetic field of 1.5 T. These values indicate that the magnetic entropy change achieved for La0.7Ca0.3Mn1-xNixO3 manganites synthesized by auto-combustion method is higher than those reported for other manganites with comparable Ni-doping levels but synthesized by standard solid state reaction. It is also observed that the addition of Ni2+ increases the value of the relative cooling power as compared to that of the parent compound. The highest value of this parameter (∼60 J/kg) is found for a Ni-doping level of 2 % around 230 K in a field of 1.5 T.

This study investigated the performance of sludge drying reed beds (SDRB) at full- and pilot-scale treating sludge from septic tanks in the city of Belo Horizonte, Brazil. The treatment units, planted with Cynodon spp., were based on an adaptation of the first-stage of the French vertical-flow constructed wetland, originally developed for treating sewage. Two different operational phases were investigated; in the first one, the full-scale unit was used together with six pilot-scale columns in order to test different feeding strategies. For the second phase, only the full-scale unit was used, including a recirculation of the filtered effluent (percolate) to one of the units of the French vertical wetland. Sludge application was done once a week emptying a full truck, during 25 weeks. The sludge was predominantly diluted, leading to low solids loading rates (median values of 18 kgTS m−2year−1). Chemical oxygen demand removal efficiency in the full-scale unit was reasonable (median of 71%), but the total solids removal was only moderate (median of 44%) in the full-scale unit without recirculation. Recirculation did not bring substantial improvements in the overall performance. The other loading conditions implemented in the pilot columns also did not show statistically different performances.

Se han propuesto muchos sistemas para la descontaminación de las aguas residuales domésticas, industriales y lixiviados. Actualmente se espera tratar las aguas residuales y derivar un beneficio económico-ambiental. Es en este contexto que los sistemas algales de alta tasa se propusieron inicialmente para el tratamiento de aguas residuales domésticas. Sin embargo, la investigación realizada alrededor de esta tecnología ha mostrado ventajas y beneficios que no se tenían contemplados inicialmente. En la actualidad se están realizando implementaciones en el tratamiento de las aguas residuales, buscando la producción de biocombustibles, bio-masa algal para alimento (animal y humano), la obtención de productos farmacéuticos y la bioprospección de las algas. Adicional a esto, se está investigando sobre la captura y reducción del dióxido de carbono (CO2) atmosférico, mecanismos de eliminación de contaminantes específicos y la optimización de la hidrobiología del sistema. Sin embargo, hace falta información sobre la función y la ecología de las algas y la relación alga/ bacteria, efecto del comportamiento hidrodinámico de la laguna sobre la ²producción algal, el efecto de las variables ambientales del trópico en el desempeño del sistema y el desarrollo de criterios de diseño para zonas tropicales. Many systems have been proposed for the decontamination of domestic and industrial wastewater and leachates. It is currently expected to treat wastewater and derive economic and environmental benefit. It is in this context that high rate algal systems (HRAPs) were originally proposed for the treatment of domestic wastewater. However, the research around this technology has shown advantages and benefits that were not initially contemplated. Actually, deployments are being made for the treatment of wastewater, seeking the production of biofuels, algal biomass for food (animal and human), obtaining pharmaceuticals and bioprospecting of algae. In addition to this, research on the capture and reduction of carbon dioxide (CO2), specific mechanisms for pollutant removal and Hydrobio-logy optimization of the system is being done. However, there is a lack of necessary information about the function and ecology of algae, the relationship algae/bacteria, the effect of hydrodynamic performance of the pond on algal production, the effect of the tropical environmental variables on the performance of the system and the developing of design standards for tropical zones.

Biosolids have great utilization potential in the agricultural sector due to its content of organic matter and nutrients. This research evaluated over a period of twelve months and at pilot scale, the influence of the application of biosolids from one wastewater treatment plant on the soil quality, the morphological characteristics of the plant, the quality of pro-duct reflected in degrees brix, sucrose and reducing sugars and the crop yield in terms of tons per hectare of a sugarcane crop. The study was executed in a complete blocks modali-ty at random form with 3 treatments: soil without nutrients application and mineral fertilization, and with biosolids appli-cation with 3 replications per treatment. It was found that the application of biosolids did not alter the microbiological and parasitological quality of the soil with regard to sanitary inter-est variables. Organic matter, mineral nitrogen, phosphorus and potassium concentrations, were found in the range of the soils of the Valle del Cauca; morphological features of the plant were found in the typical range of the variety used and the crop yield regarding sucrose, brix degrees and re-ducing sugars did not show significant statistical differences between the application of biosolids and mineral fertilization, thus ratifying the feasibility of the use of biosolids for agricul-tural application. Los biosólidos tienen alto potencial de aprovechamiento en el sector agrícola, debido a su contenido de materia orgáni-ca y de nutrientes. En esta investigación, se evaluó, durante un periodo de doce meses y en escala piloto, la influencia de la aplicación de biosólidos de una planta de tratamiento de aguas residuales sobre la calidad del suelo, las caracte-rísticas morfológicas de la planta, la calidad del producto reflejada en grados brix, sacarosa y azúcares reductores y la productividad en términos de toneladas por hectárea, de un cultivo de caña de azúcar. El estudio, se realizó en una modalidad de bloques completos al azar con 3 tratamientos: suelo sin aplicación de nutrientes y fertilización mineral y con aplicación de biosólidos, con 3 réplicas por tratamiento. Se encontró que la aplicación de los biosólidos no alteró la ca-lidad microbiológica y parasitológica del suelo, en cuanto a variables de interés sanitario. Las concentraciones de mate-ria orgánica, nitrógeno mineral, fósforo y potasio, estuvieron dentro de los rangos típicos de los suelos del Valle del Cau-ca; las características morfológicas de la planta también se encontraron en el rango típico de la variedad empleada y en el rendimiento del cultivo respecto a sacarosa, grado brix y azúcares reductores. No se encontraron diferencias estadís-ticas significativas entre la fertilización mineral y la aplicación de los biosólidos, ratificando la viabilidad de este último en actividades agrícolas. Incluye referencias bibliográficas

Phytoremediation is broadly referred to as a biotechnology that uses vegetation to contain, sequester, remove, or degrade inorganic and organic contaminants in soil, sediment, surface water, and groundwater. Its application has been recommended as cheaper and more effective alternatives for the removal and recovery of pollutants. Despite being a relatively new technology, it has great potential as a green alternative for the management of pollutants, especially in tropical areas where the rich diversity of plants means greater potential for handling different contaminants. However, its use is often limited by the unavailability of appropriate plant species. Thus, there has been recognized a list of criteria that should take into account in the process to select a plant for inclusion in phytotechnology treatment systems. Plants through different biophysical and biochemical processes, such as adsorption, transport and translocation, hyperaccumulation or transformation, and mineralization, can remediate pollutants. Constructed wetland systems (CWS) are one of the most common applications using phytoremediation. In those systems, the interactions of plants and microorganisms act for pollutant removal. Plants for phytoremediation in constructed wetlands offer, therefore, a suitable alternative for pollution cleanup, considering its wide diversity and specific characteristic of adaptation to adequate or harsh conditions throughout its life cycle. This includes acclimation to receive high or low levels of solar radiation, longer photoperiods along entire year (12 h), overcoming extended drought, high precipitation, and/or distinct wet and dry seasons. The chapter “Phytoremediation Using Terrestrial Plants” includes the main features regarding tropical native plants and its uses for this type of technology, emphasizing on constructed wetland systems as a main application of phytoremediation.

Bisphenol A (BPA) and nonylphenols (NPs), with a high potential to cause endocrine disruption, have been identified at levels of nanograms per liter and even micrograms per liter in effluents from wastewater treatment plants. Constructed wetlands (CWs) are a cost-effective wastewater treatment alternative due to the low operational cost, reduced energy consumption, and lower sludge production, and have shown promising performance for treating these compounds. A CW pilot study was undertaken todetermine its potential to remove BPA and NP from municipal wastewater. Three CWs were used: the first CW was planted with Heliconia sp., a second CW was planted with Phragmites sp., and the third CW was an unplanted control. The removal efficiency of the Heliconia-CW was 73 ± 19% for BPA and 63 ± 20% for NP, which was more efficient than the Phragmites-CW (BPA 70 ± 28% and NP 52 ± 23%) and the unplanted-CW (BPA 62 ± 33% and NP 25 ± 37%). The higher capacity of the Heliconia-CW for BPA and NP removal suggests that a native plant from the tropics can contribute to a better performance of CW for removing these compounds.

The potential of enhancing water uses using soil aquifer treatment (SAT) is an interesting alternative for tropical regions, limited only by lack of knowledge on its performance in local conditions and the feasibility of adapting this technology. A SAT pilot study was conducted to analyze the phenomena associated with the transformation of organic matter (OM) from domestic wastewater. Chemically enhanced primary effluent collected at the Cañaveralejo wastewater treatment plant (Cali, Colombia) was used to feed pilot-scale SAT units at a rate of 1.25 m.d−1. Dissolved organic carbon (DOC) removal in a 5.0 m length and 0.1 m diameter column packed with sand was 64.4%, while a similar column packed with a Mollisol soil from Valle del Cauca region yielded 56.2%. Oxygen availability was an important factor in OM degradation, given that the sand column degraded OM aerobically and the soil column degraded OM under oxic as well as anoxic conditions. SAT acted as a reliable barrier for DOC in tropical conditions. Nevertheless, operational problems such as clogging indicated that probably Mollisol soil may not be the suitable for SAT or that this particular effluent requires further pre-treatment before SAT.

Brazil and Colombia are rich in terms of water supply, ranking as world leaders in the supply of water resources. Despite this, both countries have problems of relative scarcity of this vital liquid in highly populated areas with much economic activity. Establishing policies and legal environmental standards has long tradition in both countries. However, although there are provisions and instruments for water management at the water basin level, these do not necessarily follow the conceptual development of integrated water resources management (IWRM). As a result, the two countries have partially implemented IWRM elements but with different characteristics both in its structure and instrumentality. In Colombia the State Government, through the Regional Environmental Corporations, implements IWRM (concessions, fee for water use, pollution rate, basin plans, etc), with no formal involvement of civil society management. In Brazil, however, IWRM management structure and tools are decentralized and participatory, as are the Water Basin Committees, entities where the State Government, municipalities and users participate, those with the greatest weight in water management. In Brazil, however, this model is not yet implemented in all watersheds. Thus, the aim of this paper is to compare the institutional and legal aspects of water management models in Brazil and Colombia with regard to the integrated water management concept. For the latter, we worked with a case study for each country regarding Nima River watershed (Colombia) and Tietê Jacaré (Brazil).

En este informe se presentan los resultados obtenidos a partir de un estudio meteorológico, oceanográfico y sedimentológico del golfo de Morrosquillo durante la época seca (feb/93), cuando la velocidad y dirección del viento actuaron como factores determinantes en la circulación de las aguas, la cual se definió a partir de los siguientes parámetros: Distribución de los campos halinos y térmicos, tránsito de los sedimentos depositados sobre la superficie del lecho marino, repartición horizontal y vertical de la turbidez, determinada con base en muestras de campo y calibración y análisis de una imagen de satélite SPOT. El análisis morfológico efectuado mediante la comparación del trazado de la línea de costa sobre imágenes de satélite y fotografías aéreas a diferentes años, permitió establecer las principales variaciones morfológicas en esta zona. Por efecto de difracción y refracción del oleaje frente a Punta San Bernardo y de compensación al llegar a la flecha de Mestizos, el flujo originado por estos vientos produce dos direcciones principales de corrientes: Una en sentido sureste a partir de la Punta San Bernardo, que se desplaza por la costa este del Golfo y la otra en dirección este, bordeando la costa sur y sureste. Los principales cambios morfológicos de la línea de costa se presentaron en el sector sur del Golfo. Como resultado de los procesos de acrecimiento sedimentario se originó a partir de 1938 el delta del Río Sinú al desembocar por la zona de Tinajoes, el cual actualmente continúa su evolución. Los fenómenos erosivos han afectado considerablemente el cuerpo de la flecha de Mestizos, la terraza marina al este de la espiga y el sector de playas entre Coveñas y Tolú.

Resumen Introduccion y objetivo la cistitis actinica (CAH) secundaria a la radioterapia pelvica ocurre en 2-8% de los pacientes. Se han descrito multiples tratamientos con resultados variables, habitualmente frustrantes. Nuestro objetivo fue evaluar la eficacia de la oxigenoterapia hiperbarica (OHB) como tratamiento de la CAH. Material y metodos analisis retrospectivo de los pacientes con CAH secundaria a radioterapia pelvica que recibieron OHB entre enero de 2002 y enero de 2010. Los pacientes recibieron 40 sesiones de OHB en una camara hiperbarica multiplaza, respirando 90 minutos de oxigeno al 100% a 2,2 atm. Se evaluo la respuesta con relacion al cese total o parcial de la hemorragia. Resultados veinticinco pacientes fueron tratados (21 varones y 4 mujeres), con edad promedio de 66,7 anos. Veinte hombres fueron irradiados por cancer de prostata y uno por cancer de vejiga. Tres mujeres tenian cancer de cuello uterino y una cancer de endometrio. En todos los pacientes habian fracasado los tratamientos conservadores previos y la OHB fue considerada solo tras fallar otras medidas. Todos los pacientes respondieron al tratamiento con OHB y ninguno ha presentado recidiva despues de terminar el tratamiento en un periodo de seguimiento promedio de 21,2 meses. No hubo complicaciones graves. Conclusion la OHB es un tratamiento no-invasivo, altamente eficaz y seguro para el tratamiento de la CAH secundaria a radioterapia pelvica, por lo que debe considerarse como alternativa de primera eleccion en estos complejos casos.

Se analizan los cambios de la profundidad ocurridos recientemente (un siglo) en los fondos de la bahía de Cartagena mediante la comparación de los levantamientos batimétricos de los años 1935, 1987 y 2004. También se caracteriza y analiza la distribución de los sedimentos de la bahía en su parte externa e interna. Los resultados muestran que los sedimentos de la parte interior deben su repartición y origen a dos estructuras antrópicas, la Escollera de Bocagrande y el canal del Dique. Los sedimentos del Dique ya han ocupado las partes que eran arenosas de los fondos hace pocos años y su delta ha avanzado más de un kilómetro hacia el Norte, comprometiendo la profundidad del canal navegable de acceso a Bocagrande y la bahía interna de Cartagena.

Se describen los patrones de dispersión de la pluma turbia del canal del Dique en la bahía de Cartagena mediante el análisis de 69 imágenes SPOT y los resultados de una simulación numérica para determinar los principales mecanismos de formación de los patrones de la pluma turbia en la bahía. Se detectaron seis patrones principales de la dispersión de la pluma, mediante la selección de casos homólogos. El modelo hidrodinámico aplicado permitió imitar la pluma turbia e identificar las condiciones hidro-meteorológicas para cada uno de los patrones.

Esta investigación evaluó el efecto de la irrigación con agua residual tratada, sobre el contenido de coliformes totales, E.coli y huevos de helmintos de un suelo cultivado con caña de azúcar. Se emplearon tres aguas de riego: agua de pozo, agua residual tratada por Tratamiento Primario Avanzado [TPA] y agua residual tratada por Tratamiento Primario Convencional [TPC] y se realizó seguimiento durante los doce meses de cultivo. Aunque los resultados mostraron que las aguas residuales evaluadas presentan restricción en su uso para riego agrícola, por los valores altos de coliformes totales, E. Coli y huevos de helmintos, las variables microbiológicas evaluadas al suelo mostraron que la concentración de E. Coli disminuyó desde el día de la siembra hasta el día de la cosecha y el análisis estadístico de las variables microbiológicas mostró que no existen diferencias estadísticas significativas entre los valores medios de los tratamientos.

Specific stimulation of T cells by phytohemagglutinin and Lens culinaris lectin was inhibited by a soluble factor(s) secreted by normal adherent cells stimulated with culture filtrate protein extract (CFPE) derived from bacterial cultures of Mycobacterium tuberculosis H37Ra (avirulent) and H37Rv (virulent). The induction of the inhibitory factor was blocked by the presence of hyperimmune antisera to H37Rv or H37Ra CFPE. The inhibitory factor did not seem to be a CFPE reprocessed by the adherent cells. Inhibitory activity was maximal in supernatants of adherent-cell cultures incubated for 48 h; the inhibitory factor was heat labile, and its production was dependent on the concentration of M. tuberculosis CFPE. A mouse monocyte-macrophage cell line, ATCC J774A.1, produced an identical inhibitory factor, thus excluding a non-macrophage-contaminating adherent cell as the source of the factor. This inhibitory factor also interfered with the recognition of phytohemagglutinin and Lens culinaris lectin by T cells.

Este estudio tuvo como propósito evaluar dos alternativas de reducción de patógenos; Compostaje y tratamiento alcalino en los biosólidos generados en la Planta de Tratamiento de Aguas Residuales de Cañaveralejo (PTAR-C), de Cali, Colombia.Para el compostaje se utilizó: Biosólidos; Biosólidos (B) + cachaza (C)+ residuos de poda (P); Biosolido (B) + Residuos Organicos de mercado (ROPM) + residuos de poda (P), por 61 días. El tratamiento alcalino se desarrollo por 13 días. Cal apagada y ceniza de carbón fue aplicada a: Biosólidos y al producto final del compostaje. Fueron 8, 15 y 30 % (peso/peso) las concentraciones aplicadas de ambos tipos de alcalinizantes. pH, humedad, temperatura, demanda química de Oxigeno (DQO, Nitrogeno Total Kjeldahl (NTK), Nitrogeno amoniacal (N- NH , huevos de helmintos y coliformes fecales (CF) se 4) monitorearon en ambos experimentos. Los resultados mostraron que la mejor mezcla de compost fue (B + C + P), eliminado patógenos, manteniendo la clasificación del material como Clase B, con una media geométrica para CF de 4x10-3 UFC g-1, indicando que el proceso no alcanza la clase A. La estabilización alcalina mostró que la ceniza para todas las dosis aplicadas produjo una calidad microbiológica de CF similar al compost, mostrando cierta debilidad de este material en su poder higienizante desde el punto de vista costo-eficiencia. Cal apagada al 15 y 30% produjo mejor calidad microbiológica con cero UFC g-1 de CF, alcanzando el estándar de clase A según la Agencia de Proteccion Ambiental. Esta situación puede estar asociada al incremento de pH. Para el 8% (peso/peso) la calidad fue menor a las dos anteriores y no alcanzó el estándar de clase A.