Com o objetivo de avaliar a tolerância de Betta splendens à salinidade da água, realizou-se um experimento em delineamento inteiramente casualizado, com seis concentrações de sal na água (0; 3; 6; 9; 12 e 15 g de sal comum/L de água), cada uma com cinco repetições (1 peixe/repetição). Fêmeas adultas de Betta splendens foram alojadas individualmente em aquários mantidos em estufa incubadora, a 26 ± 0,2 ºC e fotoperíodo de 12 horas. Os peixes foram alimentados até a saciedade, uma vez ao dia, com ração comercial. Foram mensurados o consumo diário de ração e a sobrevivência dos peixes a cada 12 horas. Para avaliar o efeito agudo da salinidade, foram calculados o tempo médio de sobrevivência e a salinidade letal mediana-96 horas, enquanto o efeito crônico (18 dias) foi avaliado pelo cálculo da salinidade máxima de sobrevivência e da salinidade letal mediana. O tempo médio de sobrevivência foi significativamente menor na salinidade de 15 g/L. A salinidade letal mediana-96 horas estimada foi de 11,88 g/L, a salinidade máxima de sobrevivência entre 6 e 7 g/L, e a salinidade letal mediana de 9,35 g/L. Observou-se interação significativa entre as salinidades da água e o tempo de alimentação. Considerando que é uma espécie de água doce, o beta possui alta tolerância à salinidade da água. | Salinity tolerance of Betta splendens was evaluated in a complete randomized design, with six salt concentrations in the water (0; 3; 6; 9; 12 and 15 g common salt/L) with five replications (1 fish/replication). Adult female B. splendens were individually placed in aquariums in an incubation chamber at 26 ± 0.2ºC and 12-hour photoperiod. Fish were fed to satiation, once a day, with commercial diet. Feed intake and survival rate were measured every 12 hours. To evaluate the effect of acute salinity, the mean survival time and median lethal salinity-96 h were calculated, while the chronic effect (18 days) was assessed by calculating the survival salinity maximum and median lethal salinity. The mean survival time was significantly lower at 15 g/L water salinity. The median lethal salinity-96 h calculated was 11.88 g/L, the survival salinity maximum was between 6 and 7 g/L, and the median lethal salinity was 9.35 g/L. There was a significant interaction between feeding time and water salinity. Considering that the B. splendens is a freshwater species, it was concluded that this species demonstrated a high tolerance to water salinity.

[ES] La tecnología de Altas Presiones Hidrostáticas (APH) es la tecnología no térmica de conservación de alimentos más desarrollada comercialmente, caracterizada por conseguir niveles de inactivación de microorganismos y enzimas, semejantes a los conseguidos mediante pasterización térmica, preservando en mayor medida las propiedades sensoriales y nutritivas del producto. Para conseguir esta inactivación se utilizan niveles de presión que varían entre 100-800 MPa (Mega Pascal) con tiempos relativamente cortos (en orden de segundos a varios minutos), en combinación de temperatura moderada (20-50ºC). En el presente estudio, la levadura Rhodotorula glutinis y el moho Penicillium aurantiogriseum, alteradores de la vida útil de productos alimenticios, fueron tratados utilizando presiones de 200, 300, 350 y 400 MPa por un tiempo entre 1 a 15 minutos. Los resultados obtenidos muestran que tanto R. glutinis como P. aurantiogriseum son sensibles a los tratamientos por APH. Los resultados indican que presiones de 350 MPa - 5 minutos permiten alcanzar un nivel máximo de inactivación de 5.91±0,28 ciclos logarítmicos para R. glutinis, y de 5.20±0,08 ciclos logarítmicos, para P. aurantiogriseum, con una presión de 400 MPa - 3 minutos en el medio de referencia, agua de peptona al 0.1%, con variación en las concentraciones de cloruro de sodio de (0,1-0,5-0,8%) y pH de 6.5. Las curvas de inactivación se ajustaron al modelo de distribución de Weibull. Este modelo permite ajustar curvas de inactivación no logarítmicas, es decir con hombros o con colas. | [EN] The technology of High Hydrostatic Pressure (HHP) is the non-thermal food technology more commercially developed, that has been characterized by means the achievement of microbial and enzymatic inactivation levels close to thermal pasteurization ones, preserving sensory and nutritional properties of the processed products. To achieve this level of inactivation it is used a pressure level in the range [100-800] MPa (Mega Pascal) with short treatment times (in order of seconds to several minutes), combined with moderate temperature (20-50°C). In the present study, the yeast Rhodotorula glutinis and the mold Penicillium aurantiogriseum, spoilage microorganisms responsible of the alteration of the product quality and the reduction of its shelf life, were treated by HHP at pressure levels of 200, 300, 350 and 400 MPa and treatment times from 1 to 15 minutes. The obtained results shown that both, R. glutinis and P. aurantiogriseum, are sensitive to HHP applied treatments. HHP treatment of 350 MPa - 5 min leads to a maximum inactivation level of 5.91 ± 0.28 log10 cycles for R. glutinis, achieving a maximum of 5.20 ± 0.08 log10 cycles for P. aurantiogriseum, with HHP treatment of 400 MPa - 3 min in reference media, buffered peptone water 0,1%, at concentration of sodium chloride in the range 0,1-0,8% and pH 6,5 . Inactivation kinetics were fitted to the Weibull distribution function. This model fits non logarithmic curves, i.e shoulder or tailed curves. | [CA] La tecnologia d'Altes Pressions Hidrostàtiques (APH) és la tecnologia no tèrmica de conservació d'aliments més desenvolupada comercialment, caracteritzada per aconseguir nivells d'inactivació de microorganismes i enzims, semblants als que assolim mitjançant pasteurització tèrmica, preservant en major mesura les propietats sensorials i nutritives del producte. Per aconseguir esta inactivació s'utilitzen nivells de pressió que varien entre 100-800 MPa (Mega Pascal) amb temps relativament curts (en ordre de segons a diversos minuts), en combinació amb temperatura moderada (20-50 º C). En este estudi, el llevat Rhodotorula glutinis i la floridura Penicillium aurantiogriseum, alteradors de la vida útil de productes alimentaris, van ser tractats utilitzant pressions de 200, 300, 350 i 400 MPa per un temps entre 1 a 15 minuts. Els resultats obtinguts mostren que tant R. glutinis i P. aurantiogriseum són sensibles als tractaments per APH. Els resultats indiquen que pressions de 350 MPa - 5 minuts permeten assolir un nivell màxim d'inactivació de 5.91 ± 0,28 cicles logarítmics per R. glutinis, aconseguint una inactivació màxima de 5.20 ± 0,08 cicles logarítmics, per P. aurantiogriseum, amb una pressió de 400 MPa - 3 minuts en el medi de referència, aigua de peptona al 0.1%, amb variació en les concentracions de clorur de sodi (0,1-0,5-0,8%) i pH de 6.5. Les corbes d'inactivació es van ajustar a un model no linial: el model de distribució de Weibull. | Torres Bello, EF. (2013). Inactivación por altas presiones hidrostaticas de Rhodotorula glutinis y Penicillium aurantiogriseum en medio referencia agua peptona. http://hdl.handle.net/10251/27961.

The Agua Negra drainage system (30 12'S, 69 50' W), in the Argentine Andes holds several ice- and rock-glaciers, which are distributed from 4200 up to 6300 m a.s.l. The geochemical study of meltwaters reveals that ice-glaciers deliver a HCO₃⁻----Ca²⁺ solution and rock-glaciers a SO₄²⁻----HCO₃⁻----Ca²⁺ solution. The site is presumably strongly influenced by sublimation and dry deposition. The main processes supplying solutes to meltwater are sulphide oxidation (i.e. abundant hydrothermal manifestations), and hydrolysis and dissolution of carbonates and silicates. Marine aerosols are the main source of NaCl. The fine-grained products of glacial comminution play a significant role in the control of dissolved minor and trace elements: transition metals (e.g. Mn, Zr, Cu, and Co) appear to be selectively removed from solution, whereas some LIL (large ion lithophile) elements, such as Sr, Cs, and major cations, are more concentrated in the lowermost reach. Daily concentration variation of dissolved rare earth elements (REE) tends to increase with discharge. Through PHREEQC inverse modelling, it is shown that gypsum dissolution (i.e. sulphide oxidation) is the most important geochemical mechanism delivering solutes to the Agua Negra drainage system, particularly in rock-glaciers. At the lowermost reach, the chemical signature appears to change depending on the relative significance of different meltwater sources: silicate weathering seems to be more important when meltwater has a longer residence time, and calcite and gypsum dissolution is more conspicuous in recently melted waters. A comparison with a non-glacierized semiarid drainage of comparable size shows that the glacierized basin has a higher specific denudation, but it is mostly accounted for by relatively soluble phases (i.e. gypsum and calcite). Meltwater chemistry in glacierized arid areas appears strongly influenced by sublimation/evaporation, in contrast with its humid counterparts.

Mandalay is a major city in central Myanmar with a high urban population and which lacks a central wastewater management system, a solid waste disposal process, and access to treated drinking water. The purpose of this study is to investigate the groundwater quality of local dug wells and tube wells, determine quantitative data on characteristics of the Amarapura Aquifer, and compare seasonal variations in groundwater flow and quality. Water samples were collected during the dry and wet seasons, then analyzed for major ion chemistry using ion chromatography to identify indicators of wastewater contamination transport to the shallow aquifer and to compare seasonal variations in groundwater chemistry. An open-source analytic element model, GFLOW, was used to describe the physical hydrogeology and to determine groundwater flow characteristics in the aquifer. Hydrogeochemistry data and numerical groundwater flow models provide evidence that the Amarapura Aquifer is susceptible to contamination from anthropogenic sources. The dominant water types in most dug wells and tube wells is Na-Cl, but there is no known geologic source of NaCl near Mandalay. Many of these wells also contain water with high electrical conductivity, chloride, nitrate, ammonium, and E. coli. Physical measurements and GFLOW characterize groundwater flow directions predominantly towards the Irrawaddy River and with average linear velocities ranging from 1.76 × 10⁻² m/day (2.04 × 10⁻⁷ m/s) to 9.25 m/day (1.07 × 10⁻⁴ m/s). This is the first hydrogeological characterization conducted in Myanmar.

Com o objetivo de avaliar a tolerância de Betta splendens à salinidade da água, realizou-se um experimento em delineamento inteiramente casualizado, com seis concentrações de sal na água (0; 3; 6; 9; 12 e 15 g de sal comum/L de água), cada uma com cinco repetições (1 peixe/repetição). Fêmeas adultas de Betta splendens foram alojadas individualmente em aquários mantidos em estufa incubadora, a 26 ± 0,2 ºC e fotoperíodo de 12 horas. Os peixes foram alimentados até a saciedade, uma vez ao dia, com ração comercial. Foram mensurados o consumo diário de ração e a sobrevivência dos peixes a cada 12 horas. Para avaliar o efeito agudo da salinidade, foram calculados o tempo médio de sobrevivência e a salinidade letal mediana-96 horas, enquanto o efeito crônico (18 dias) foi avaliado pelo cálculo da salinidade máxima de sobrevivência e da salinidade letal mediana. O tempo médio de sobrevivência foi significativamente menor na salinidade de 15 g/L. A salinidade letal mediana-96 horas estimada foi de 11,88 g/L, a salinidade máxima de sobrevivência entre 6 e 7 g/L, e a salinidade letal mediana de 9,35 g/L. Observou-se interação significativa entre as salinidades da água e o tempo de alimentação. Considerando que é uma espécie de água doce, o beta possui alta tolerância à salinidade da água.<br>Salinity tolerance of Betta splendens was evaluated in a complete randomized design, with six salt concentrations in the water (0; 3; 6; 9; 12 and 15 g common salt/L) with five replications (1 fish/replication). Adult female B. splendens were individually placed in aquariums in an incubation chamber at 26 ± 0.2ºC and 12-hour photoperiod. Fish were fed to satiation, once a day, with commercial diet. Feed intake and survival rate were measured every 12 hours. To evaluate the effect of acute salinity, the mean survival time and median lethal salinity-96 h were calculated, while the chronic effect (18 days) was assessed by calculating the survival salinity maximum and median lethal salinity. The mean survival time was significantly lower at 15 g/L water salinity. The median lethal salinity-96 h calculated was 11.88 g/L, the survival salinity maximum was between 6 and 7 g/L, and the median lethal salinity was 9.35 g/L. There was a significant interaction between feeding time and water salinity. Considering that the B. splendens is a freshwater species, it was concluded that this species demonstrated a high tolerance to water salinity.

The use of snowmelt as an inexpensive multi-component tracer solution for active aquifer characterization is investigated, creating a valid alternative to existing artificial water isotope labelling using enriched deuterium oxide (²H₂O) and water-¹⁸O (H₂¹⁸O). The approach directly takes advantage of natural differences between groundwater and precipitation. It is shown, at laboratory-scale and small field-scale, that a direct injection of snowmelt into a porous medium allows for the tracing of water flow and, therefore, for the determination of transport parameters based on the stable isotope signatures (δ²H and δ¹⁸O) and on the sum parameter electrical conductivity (EC). The differences in the isotope signature between the snowmelt and groundwater applied in this study were significant, with ∆(δ²H) = 61.0‰ and ∆(δ¹⁸O) = 8.2‰, while the EC difference was ~0.5 mS/cm. Stable isotope breakthrough was observed to be almost congruent to sodium chloride (laboratory tracer experiment) and to uranine (field-scale push-drift-pull test), clearly supporting the assumption of conservative transport. A crosscheck of the isotope data in δ²H-δ¹⁸O plots revealed no significant biases in the tests. On the other hand, the snowmelt’s EC breakthrough suffered from a slight retardation due to ion exchange and mineral reactions.

The maximum upward flux (Eₘₐₓ) is a control condition for the development of groundwater evaporation models, which can be predicted through the Gardner model. A high-precision Eₘₐₓ prediction helps to improve irrigation practice. When using the Gardner model, it has widely been accepted to ignore parameter b (a soil-water constant) for model simplification. However, this may affect the prediction accuracy; therefore, how parameter b affects Eₘₐₓ requires detailed investigation. An indoor one-dimensional soil-column evaporation experiment was conducted to observe Eₘₐₓ in the presence of a water table of depth 50 cm. The study consisted of 13 treatments based on four solutes and three concentrations in groundwater: KCl, NaCl, CaCl₂, and MgCl₂, with concentrations of 5, 30, and 100 g/L (salty groundwater); distilled water was used as a control treatment. Results indicated that for the experimental homogeneous loam, the average Eₘₐₓ for the treatments supplied by salty groundwater was larger than that supplied by distilled water. Furthermore, during the prediction of the Gardner-model-based Eₘₐₓ, ignoring b and including b always led to an overestimate and underestimate, respectively, compared to the observed Eₘₐₓ. However, the maximum upward flux calculated including b (i.e. Ebₘₐₓ) had higher accuracy than that ignoring b for Eₘₐₓ prediction. Moreover, the impact of ignoring b on Eₘₐₓ gradually weakened with increasing b value. This research helps to reveal the groundwater evaporation mechanism.