Search

Chile, the world's leading copper producer, generates significant volumes of mining waters, some of which cannot be recirculated into the production process. These mining waters are characterized by elevated sulfate ( SO 4 2 − ) concentrations, requiring sustainable management strategies for potential reuse. This study aims to evaluate the rhizofiltration technique using Carpobrotus chilensis for treating mining waters with a high SO 4 2 − concentration. Initially, the mining waters exhibited a pH of 7.97 ± 0.16 and a SO 4 2 − concentration of 2,743 ± 137 mg L−1, while the control water had a pH of 7.88 ± 0.08 and a SO 4 2 − concentration of 775 ± 19.0 mg L−1. The plants were hydroponically cultivated in 40 L containers with mining waters and drinking water as a control. Over an 8-week period, the pH of the mining water decreased to 3.12 ± 0.01, and the SO 4 2 − concentration declined to 2,200 ± 110 mg L−1. Notably, the fresh weight of roots was significantly higher in plants grown in mining water (22.2 ± 6.66 g) compared to those in the control treatment (14.3 ± 4.28 g). However, an undesirable increase in the acidity was observed in the mining waters after rhizofiltration, which was attributed to hydrogen sulfate (HSO4-) and/or root exudates. Despite the unexpected increase in acidity, C. chilensis effectively reduced the concentration of SO 4 2 − in mining waters by 20%. Additionally, the C. chilensis roots accumulated 4.84 ± 1.40% of sulfur (S), a level comparable to thiophore plants. This study provides evidence that this non-aquatic plant can be used in sulfate rhizofiltration. Caprobrotus chilensis is a good candidate for sulfate rhizolfiltration in mining waters. The accumulation of sulfur by the roots of Carpobrotus chilensis reached 4.84% Mining waters with a high concentration of sulfates require control of the redox potential [ABSTRACT FROM AUTHOR]

The indoor airflow with a natural ventilation system was numerically calculated using the laminar and turbulent approach. In the chemical laboratory of the Technical University of Ambato, the computational code OpenFoam demonstrated an ability to numerically predict flow patterns. The design contemplated the natural ventilation system considering the laboratories’ working conditions not only in summer, but also in a winter week. These two operating conditions are calculated on a fully open and closed environment. For a room with a capacity of 20 people, the climate data average values were recorded at 14.0 ° C, 81.7%, 1.7 m /s for temperature, relative humidity, and wind speed, respectively. Furthermore, the demonstration has shown that the homogeneous occupancy air speed average is was 0.7 m / s with a facade air intake of 1.0 m / s 0.6 m / s in the room valid for the exchange of air and evacuation of pollutants. The maximum pressures were found in the lower part of the laboratory. This prevents the modification of the thermo-hygrometric conditions.

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Critical fabrication process factors were examined using a Taguchi experimental matrix for their effect on high-temperature superconducting (HTS) edge junction fabrications. These factors include angle of HTS deposition by pulsed laser deposition (PLD), pre-cleaning and annealing dwell time prior to epitaxial depositions and angle of film edges created by ion milling. Experimental results show that of all three factors, the base electrode deposition technique significantly affects the junction critical current spread and performance.

Copyright of Entre Ciencia e Ingeniería is the property of Entre Ciencia e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The electrical sensitivity of glass fiber/multiwall carbon nanotube/vinyl ester hierarchical composites containing a tailored electrically-percolated network to self-sense accumulation of structural damage when subjected to cyclic tensile loading-unloading is investigated. The hierarchical composites were designed to contain two architectures differentiated by the location of the multiwall carbon nanotubes (MWCNTs), viz. MWCNTs deposited on the fibers and MWCNTs dispersed within the matrix. The changes in electrical resistance of the hierarchical composites are associated to their structural damage and correlated to acoustic emissions. The results show that such tailored hierarchical composites are able to self-sense damage onset and accumulation upon tensile loading-unloading cycles by means of their electrical response, and that the electrical response depends on the MWCNT location. [ABSTRACT FROM AUTHOR]

Rosmarinus officinalisis an important aromatic shrub cultivated for medicinal, culinary, and ornamental uses. To assess growth, the contents of trace metals cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn), lead (Pb), and zinc (Zn) and macronutrients calcium (Ca), magnesium (Mg), potassium (K), nitrogen (N), and phosphorus (P) were measured in these plants cultivated on two substrates: pine bark (PB, pH 4.0, 80.5% organic matter) and pruning wastes–biosolids (BS, pH 6.9, 47.5% organic matter).These plants, initially of 3.5 ± 0.5 g dry weight and 31.1 ± 6.9 cm, were maintained under greenhouse conditions for 7 months. Nutrient solution samples were taken from each substrate in situ by rhizon probes, indicating that the concentrations of soluble Mn and Zn in PB were significantly greater than in the nutritive solution BS. At the end of the assay, the dry weight of leaves and height was significantly greater in plants cultivated in BS (40.0 ± 2.2 g and 75.9 ± 14.3 cm) than in PB (27.5 ± 4.0 g and 62.4 ± 10.2 cm). Plants cultivated in PB showed slight chlorosis, attributed to the high concentration of Mn in leaves (106.6 ± 7.8 mg kg−1), which was much greater than in plants cultivated in BS (8.2 ± 0.9 mg kg−1). The concentration of toxic metals Cd and Pb in plants cultivated on both substrates did not exceed the recommended levels for consumption of the leaves as condiment. IfR. officinalisis cultivated on the substrate of pine bark to acid pH for food or medicinal use, the accumulation of Mn must be considered. [ABSTRACT FROM AUTHOR]

Abstract: Land use change alters water and element cycles, but the changes in these cycles after conversion for example from cropland to forest are not fully described in hydrological and nutrient transport models, which usually describe either cropland or forest stands. In the European Union future afforestation is likely to occur on abandoned cropland, and evaluation of the future impacts of this land use change will require projections with models that include combined cropland-forest modules. This study used the agro-based DAISY model (Version 4.93 to investigate changes in the soil water balance over four decades following afforestation of a homogeneous area of former arable land on a sandy loam in Denmark. Hydrological data collected during nine hydrological years (April 2001-March 2010) were used to test the DAISY model. Monthly data on soil water content at 0-90cm used for calibration were available from April 2001 to December 2002 for six monoculture stands of oak (age 8, 22 and 31 years) and Norway spruce (age 4, 13 and 32 years). Model performance was evaluated by considering uncertainties in model i puts using GLUE procedure The GLUE estimates obtained (uncertainty bands 5% and 95%) agreed satisfactorily with measured monthly soil water content during the calibration period (April 2001- December 2002). Similarly, in the oldest oak stand, long- term monitoring observations and predictions of monthly water content were in satisfactory agreement during the period January 2003-March 2010). Sensitivity analysis showed that the DAISY model was most sensitive to the Kc and soil hydraulic parameters included in the Campbell model. Simulation results during nine hydrological years showed that 16-25% of incoming precipitation led to water recharge in the spruce stands, while the corresponding range for oak stands was 25-27%. A 35-year DAISY simulation revealed that Norway spruce consumed more water than oak, with differences in annual water recharge in the range 31-174mm year-1 and with greater differences in rainy years (precipitation >900mm year-1). [Copyright &y& Elsevier]

The present work was carried out at the 'Montelindo' farm (property of Univerdidad de Caldas), located at 1,010 masl, with average temperature of 23.5°C, annual rainfall of 2,100 mm and 76%, relative humidity. The objective was to evaluate various agents of biological and organic management of plant-parasitic nematodes that affect the plantain crop. To control nematodes, applications of vermicompost, mycorrhiza, Trichoplant®, Carbofed® 330 SC and lixiviates of plantain rachis were made. Treatments were distributed in a split plot experimental design. Whether the application of lixiviates would or would not be carried out, was assigned to main plots while the nine treatments were randomly assigned to sub-plots, with four replicates. Five plants were used per replicate. Registers of number of parasitic-nematodes in soil and roots were made every three months for 9 months after planting. It was established that the most frequent genera of plant-parasitic nematodes were Radopholus, Meloidogyne and Helicotylenchus; that the product vermicompost favored the presence of these nematodes even 9 months after planting; that in all of the treatments the populations of plant-parasitic nematodes tended to increase following 6 months after the planting date; that the products that presented the best results were Carbofed® 330 SC and Trichoplant®; that the lixiviate of plantain rachis only had adverse effects on nematodes 9 months after planting and that the nematode that most affects the plantain root system showing resistance to any type of control is Radopholus similis. [ABSTRACT FROM AUTHOR]

To improve downstream processing, protein engineering can be used to modify particular properties of a protein, such as specific affinity, charge, or hydrophobicity. The most common modification involves the peptide tags fusion to the protein. Nevertheless, the selection of both the optimal peptide tag and the right purification system to use is not trivial. The aim of this work is to experimentally validate our previous mathematical model based on MINLP models. This model was modified to find the minimum number of chromatographic operations, and the ideal tag for obtaining a required level of purification. A weighted linear combination of the number of purification steps and the target protein purity obtained after the last step was used as the objective function. The chromatographic steps suggested by the model were carried out using an example based on two mutated cutinases. The results show that average deviations between experimental data and those predicted by the model, for yield and purity, are ca. 15%, confirming that model predictions are reliable and could be used for selecting the best purification processes without experimental tests. [ABSTRACT FROM AUTHOR]

Abstract: The present study evaluated the effect of FSH treatment on ovarian cell proliferation in the hypophysectomized chicken embryo. Hypophysectomy (Hx) was performed by the partial decapitation technique. Two series of experiments were performed: (a) Hx embryos were treated at 8 days of development with recombinant human FSH (rhFSH) and evaluated at 9 days by measuring BrdU incorporation; (b) Hx embryos were injected with rhFSH and rhCG at 9 days of development and the proliferation rate was measured at 13 days. The presence of mRNA for FSHR and LHR in the ovary of control and Hx embryos was demonstrated by RT-PCR analysis. There was a decrease in the percentage of BrdU labeled cells in the absence of hypophysis at 9 and 13 days of incubation. The decrease was reversed with rhFSH treatment. This effect was observed in the ovarian surface epithelium and the somatic cells of the cortex and the medulla in the 9-day-old embryo. Moreover, the number of somatic, steroidogenic, and germ cells was reduced at 13 days of incubation in the Hx embryo; when treated with rhFSH the number of cells increased to the level of controls. In another experiment, ovaries of 9-day-old chicken embryos were organ cultured for 48h in a serum-free medium with rhFSH and rhCG separately. The proliferation index was incremented by rhFSH compared to control and rhCG-treated embryos. Therefore, FSH stimulates somatic cell proliferation in the chicken embryo ovary as early as 9 days of development. [Copyright &y& Elsevier]