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Animal activities, such as foraging and reproduction, are constrained by decisions about how to allocate energy and time efficiently. Overall, male moths invest less in reproduction than females, but they are thought to engage in a scramble competition for access to females that advertise readiness to mate by releasing sexual pheromones. However, before male moths can follow the pheromone, they often need to heat their flight muscles by shivering to produce sufficient power for sustained flight. Here, we show that Helicoverpa zea males that sense the female pheromone at high ambient temperatures take off with higher thoracic temperature, shiver for less time and warm up faster than males tested at lower ambient temperatures. These higher take-off temperatures translate into higher airspeeds, underscoring the importance of thoracic temperature for flight performance. Furthermore, shorter combined duration for warm-up and pheromone-mediated optomotor anemotaxis is consistent with the idea that males engage in scramble competition for access to females in nature. Our results strongly suggest that male moths minimize the time between perceiving the female's pheromone signal and arriving at the source by optimizing thermoregulatory behaviour and temperature-dependent flight performance in accordance with ambient temperature conditions. Our finding that moths engage in a trade-off between rapid flight initiation and suboptimal flight performance suggests a sensorimotor control mechanism that involves a complex interaction with the thermal environment.

The impact of surface topography on the structure of proteins upon adhesion was assessed through non-invasive fluorescence monitoring. This study aimed at obtaining a better understanding about the role of protein structural status on cell-scaffold interactions. The changes induced upon adsorption of two model proteins with different geometries, trypsin (globular conformation) and fibrinogen (rod-shaped conformation) on poly-l-lactic acid (PLLA) scaffolds with different surface topographies, flat, fibrous and surfaces with aligned nanogrooves, were assessed by fluorescence spectroscopy monitoring, using tryptophan as structural probe. Hence, the maximum emission blue shift and the increase of fluorescence anisotropy observed after adsorption of globular and rod-like shaped proteins on surfaces with parallel nanogrooves were ascribed to more intense protein-surface interactions. Furthermore, the decrease of fluorescence anisotropy observed upon adsorption of proteins to scaffolds with fibrous morphology was more significant for rod-shaped proteins. This effect was associated to the ability of these proteins to adjust to curved surfaces. The additional unfolding of proteins induced upon adsorption on scaffolds with a fibrous morphology may be the reason for better cell attachment there, promoting an easier access of cell receptors to initially hidden protein regions (e.g. RGDS sequence), which are known to have a determinant role in cell attaching processes., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Hypothesis: Magnetic Ionic Liquid (MILs), novel magnetic molecules that form "pure magnetic liquids," will follow the Ferrohydrodynamic Bernoulli Relationship. Based on recent literature, the modeling of this fluid system is an open issue and potentially controversial., Experiments: We imposed uniform magnetic fields parallel to MIL/air interfaces where the capillary forces were negligible, the Quincke Problem. The size and location of the bulk fluid as well as the size and location of the fluid/air interface inside of the magnetic field were varied. MIL properties varied included the density, magnetic susceptibility, chemical structure, and magnetic element., Findings: Uniform tangential magnetic fields pulled the MILs up counter to gravity. The forces per area were not a function of the volume, the surface area inside of the magnetic field, or the volume displacement. However, the presence of fluid/air interfaces was necessary for the phenomena. The Ferrohydrodynamic Bernoulli Relationship predicted the phenomena with the forces being directly related to the fluid's volumetric magnetic susceptibility and the square of the magnetic field strength. [emim][FeCl4] generated the greatest hydraulic head (64-mm or 910 Pa at 1.627 Tesla). This work could aid in experimental design, when free surfaces are involved, and in the development of MIL applications., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Unlabelled: Natural extracts obtained from grape pomace are particularly interesting, due to the substantial variety of valuable compounds present with health benefits, specifically phenolic compounds such as anthocyanins, trans-resveratrol, quercetin, and proanthocyanidins. The production of such extracts has been recognized as a profitable way to valorize grape byproducts, which are low-value and most abundant. First, the effect of the solvent on the extraction of bioactive compounds from grape pomace is studied. The selected solvents are water and ethanol, biocompatible and available in wineries and distilleries. Then, different types of grape pomace obtained along the various stages of current industrial winemaking and distillation processes are analyzed. As a result, the best stage of the winemaking and distillation processes for pomace valorization is identified, corresponding to the grape byproduct with the highest potential as source of bioactive compounds. These studies were performed with Vitis vinifera variety of Tempranillo grapes (same year, same vineyard)., Practical Application: This work optimizes the production of natural extracts from (byproduct) grape pomace with recognized health benefits, to be used as high value nutraceuticals ingredients. The process proposed uses renewable and low-cost resources existent in wineries and distilleries. The select solvent extracting is a mixture of the biocompatible water and ethanol. The selected fermented grape pomace was chosen from different and comparable types of grape pomace obtained at current winemaking and distillation processes, to be used in extraction without any pretreatment., (© 2014 Institute of Food Technologists®)

Mercury is a highly toxic heavy metal that causes human health problems and environmental contamination. In this study, an ion exchange membrane bioreactor (IEMB) process was developed to achieve Hg(II) removal from drinking water and industrial effluents. Hg(II) transport through a cation exchange membrane was coupled with its bioreduction to Hg(0) in order to achieve Hg removal from concentrated streams, with minimal production of contaminated by-products observed. This study involves (1) membrane selection, (2) demonstration of process effectiveness for removing Hg from drinking water to below the 1ppb recommended limit, and (3) process application for treatment of concentrated water streams, where >98% of the Hg was removed, and the throughput of contaminated water was optimised through membrane pre-treatment. The IEMB process represents a novel mercury treatment technology with minimal generation of contaminated waste, thereby reducing the overall environmental impact of the process., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this study, a nanofiltration unit was implemented at an industrial site, for the treatment of industrial wastewater generated during rubber tubing extrusion. The aim was to reduce the energy input required, while assuring a final effluent quality that meets the requirements of environmental legislation. In a first stage, two membrane process treatments, ultrafiltration and nanofiltration, were evaluated at laboratory scale in order to assess the rejection of pollutants and maximise permeate throughput. Permeate generated from nanofiltration using either an NF90 or an NF270 membrane were shown to meet the effluent discharge requirements (<2000 mg COD/l). The less restrictive membrane, NF270, was chosen for study in a pilot plant at the industrial site, due to its higher membrane permeability. The pilot nanofiltration unit was integrated into the treatment plant operation aiming at optimising the process in terms of the efficiency of pollutant removal with minimal energy input. A feasibility study was performed for this case-study and it was concluded that the energy expenditure of the new process represents only 62% of the current energy consumption of the treatment plant. The proposed solution in this work may be retrofitted to full scale wastewater treatment processes, and may be applicable to industries that employ similar manufacturing processes, and face similar difficulties., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The quick detection of domestic and peridomestic triatomines in their environments becomes difficult without the use of dislodgement substances that flush them out from their shelters. At present, tetramethrin 0.2% is being widely used in control programs. Although it is an efficient dislodging agent, its toxicity might affect the health of captured triatomines, of other insects and, to a lesser extent, of other animals, including humans. Here, we tested if semiochemicals released by disturbed adults of Triatoma infestans and/or Rhodnius prolixus can make larvae of the same species exit from their refuges. In a walking olfactometer we found that: 1) larvae of T. infestans were repelled by the odors released by disturbed adults of their own species and of R. prolixus, 2) larvae of R. prolixus did not change their behavior in the presence of odors released by adults of both species, and 3) activity levels were not modulated by these odors in any of both species. Besides, in pseudo-natural conditions we found an increased flushing-out activity of larvae of T. infestans when their shelters were sprayed with isobutyric acid or 3-pentanol, and of larvae of R. prolixus when sprayed with 3-methyl-1-butanol. We succeeded in this work to dislodge larvae of triatomines from artificial shelters using natural volatile compounds, allowing the capture of live bugs for further investigations (e.g., xenodiagnosis or genetic studies) and favoring ecological aspects (e.g., minimizing environmental insecticide-contamination and non-targeted mortality)., (© 2013 The Society for Vector Ecology.)

Transport properties of natural (noncompressed) cork were evaluated for water and ethanol in both vapor and liquid phases. The permeability for these permeants has been measured, as well as the sorption and diffusion coefficients. This paper focuses on the differences between the transport of gases' relevant vapors and their liquids (water and ethanol) through cork. A transport mechanism of vapors and liquids is proposed. Experimental evidence shows that both vapors and liquids permeate not only through the small channels across the cells (plasmodesmata), as in the permeation of gases, but also through the walls of cork cells by sorption and diffusion as in dense membranes. The present study also shows that cork permeability for gases was irreversibly and drastically decreased after cork samples were exposed to ethanol or water in liquid phase.

A study is presented of the molecular dynamics and of the viscosity in pure [Aliquat][Cl] ionic liquid and in a mixture of [Aliquat][Cl] with 1% (v/v) of [Aliquat][FeCl4]. The (1)H spin-lattice relaxation rate, R1, was measured by NMR relaxometry between 8 and 300 MHz. In addition, the translation self-diffusion, D, was measured by pulse field gradient NMR. The ILs' viscosity was measured as a function of an applied magnetic field, B, and it was found that the IL mixture's viscosity decreased with increasing B, whereas the [Aliquat][Cl] viscosity is independent of B. All experimental results were analyzed taking into account the viscosity's magnetic field dependence, assuming a modified Stokes-Einstein diffusion/viscosity relation. The main difference between the relaxation mechanisms responsible for R1 in the two IL systems is related to the additional paramagnetic relaxation contribution associated with the (1)H spins-[FeCl4] paramagnetic moments' interactions. Cross-relaxation cusps in the R1 dispersion, associated with (35)Cl and (1)H nuclear spins in the IL systems, were detected. The R1 model considered was successfully fitted to the experimental results, and it was possible to estimate the value of D at zero field in the case of the IL mixture which was consistent with the values of D measured at 7 and 14.1 T and with the magnetic field dependence estimated from the viscosity measurements. It was observed that a small concentration of [Aliquat][FeCl4] in the [Aliquat][Cl] was enough to produce a "superparamagnetic"-like effect and to change the IL mixture's molecular dynamics and viscosity and to allow for their control with an external magnetic field.

At low ambient temperature Helicoverpa zea male moths engage in warm-up behavior prior to taking flight in response to an attractive female pheromone blend. Male H. zea warm up at a faster rate when sensing the attractive pheromone blend compared with unattractive blends or blank controls (Crespo et al. 2012), but the mechanisms involved in this olfactory modulation of the heating rate during preflight warm-up are unknown. Here, we test three possible mechanisms for increasing heat production: 1) increased rate of muscle contraction; 2) reduction in mechanical movement by increased overlap in activation of the antagonistic flight muscles; and 3) increased activation of motor units. To test which mechanisms play a role, we simultaneously recorded electrical activation patterns of the main flight muscles (dorsolongitudinal and dorsoventral muscles), wing movement, and thoracic temperature in moths exposed to both the attractive pheromone blend and a blank control. Results indicate that the main mechanism responsible for the observed increase in thoracic heating rate with pheromone stimulation is the differential activation of motor units during each muscle contraction cycle in both antagonistic flight muscles. This additional activation lengthens the contracted state within each cycle and thus accounts for the greater heat production. Interestingly, the rate of activation (frequency of contraction cycles) of motor units, which is temperature dependent, did not vary between treatments. This result suggests that the activation rate is determined by a temperature-dependent oscillator, which is not affected by the olfactory stimulus, but activation of motor units is modulated during each cycle.

In the present study, the performance of a membrane bioreactor (MBR) was modelled using a hybrid approach based on the activated sludge model number 3 (ASM3) combined with projection to latent structures (PLS) to predict the residuals of the ASM. The application of ASM to MBRs requires frequent re-calibration to adjust the model to variations in influent characteristics, determined through time-consuming analysis and batch tests. Considering this problem, the objective of this study was to improve ASM prediction ability with minimal additional monitoring effort. Hybrid models were developed to predict three MBR performance parameters: mixed liquor suspended solids (MLSS), COD in the permeate (CODp) and nitrite and nitrate concentration in the permeate (NOxp). For PLS modelling of ASM residuals three input strategies were used: (1) analytic and operating data; (2) operating data plus 2D fluorescence spectroscopy; (3) all the data. The first input strategy improved ASM prediction of the three selected outputs, and highlighted the lack of detailed and real-time information from wastewater and operating parameters in the ASM used in this study. In the second input strategy, the incorporation of updated data from 2D fluorescence spectroscopy resulted on better model fitting than in the first input strategy, for all the output parameters studied. Through the hybrid modelling approach it was possible to significantly improve the ASM predictions in real-time using 2D fluorescence measurements and other relevant parameters acquired on-line, without requiring further laboratory analysis. Furthermore, the third input strategy, incorporating all the collected data, did not significantly improve the prediction of the outputs beyond the second strategy. This shows that 2D fluorescence spectroscopy is a comprehensive monitoring tool, able to capture on-line the required information to complement, through hybrid modelling, the mechanistic information described by an ASM., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A combined fluorescence analysis, involving the use of steady-state fluorescence and fluorescence anisotropy was used, allowing eliciting information about the structural changes induced on trypsin after exposure to membrane surfaces with diverse chemistry, designed through a layer-by-layer methodology. Using this monitoring strategy it was possible to understand the influence of the surface chemistry on the structural characteristics of the attached proteins and how they relate to changes of their activity resulting from the adsorption process. This knowledge may be used to direct the development of surfaces with suitable chemistry, leading enzymatic-based processes with improved performance. The results obtained show clearly that trypsin exposed to different membrane surfaces, changes its conformation, either if it adsorbs to the membrane or if it remains in solution. A significant loss of enzymatic activity was observed upon the adsorption process, for the adsorbed and non-adsorbed protein. This loss of the trypsin activity was correlated with the presence of molecular unfolding events that mediate trypsin-membrane surface interactions and the decrease of the molecular mobility of the adsorbed trypsin, which was shown to be dependent on the chemical characteristics of the membrane surface. Changes on the selectivity of the adsorbed trypsin were also observed, and may be ruled by the strength of the enzyme-surface interactions established., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The biological degradation of nitrate and perchlorate was investigated in an ion exchange membrane bioreactor (IEMB) using a mixed anoxic microbial culture and ethanol as the carbon source. In this process, a membrane-supported biofilm reduces nitrate and perchlorate delivered through an anion exchange membrane from a polluted water stream, containing 60 mg/L of NO₃⁻ and 100 μg/L of ClO₄⁻. Under ammonia limiting conditions, the perchlorate reduction rate decreased by 10%, whereas the nitrate reduction rate was unaffected. Though nitrate and perchlorate accumulated in the bioreactor, their concentrations in the treated water (2.8 ± 0.5 mg/L of NO₃⁻ and 7.0 ± 0.8 μg/L of ClO₄⁻, respectively) were always below the drinking water regulatory levels, due to Donnan dialysis control of the ionic transport in the system. Kinetic parameters determined for the mixed microbial culture in suspension showed that the nitrate reduction rate was 35 times higher than the maximum perchlorate reduction rate. It was found that perchlorate reduction was inhibited by nitrate, since after nitrate depletion perchlorate reduction rate increased by 77%. The biofilm developed in the IEMB was cryosectioned and the microbial population was analyzed by fluorescence in situ hybridization (FISH). The results obtained seem to indicate that the kinetic advantage of nitrate reduction favored accumulation of denitrifiers near the membrane, whereas per(chlorate) reducing bacteria were mainly positioned at the biofilm outer surface, contacting the biomedium. As a consequence of the biofilm stratification, the reduction of perchlorate and nitrate occur sequentially in space allowing for the removal of both ions in the IEMB., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

This work presents the development of multivariate statistically-based models for monitoring several key performance parameters of membrane bioreactors (MBR) for wastewater treatment. This non-mechanistic approach enabled the deconvolution of 2D fluorescence spectroscopy data, a powerful technique that has previously been shown to capture important information regarding MBR performance. Projection to latent structure (PLS) modelling was used to integrate 2D fluorescence data, after compression through parallel factor analysis (PARAFAC), with operation and analytical data to describe an MBR fouling indicator (transmembrane pressure, TMP), five descriptors of the effluent quality (total COD, soluble COD, concentration of nitrite and nitrate, total nitrogen and total phosphorus in the permeate) and the biomass concentration in the bioreactor (MLSS). A multilinear correlation was successfully established for TMP, CODtp and CODsp, whereas the optimised models for the remaining outputs included quadratic and interaction terms of the compressed 2D fluorescence matrices. Additionally, the coefficients of the optimised models revealed important contributions of some of the input parameters to the modelled outputs. This work demonstrates the applicability of 2D fluorescence and statistically-based models to simultaneously monitor multiple key MBR performance parameters with minimal analytical effort. This is a promising approach to facilitate the implementation of MBR technology for wastewater treatment., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

An essential part of sexual reproduction typically involves the identification of an appropriate mating partner. Males of many moth species utilize the scent of sex pheromones to track and locate conspecific females. However, before males engage in flight, warm-up by shivering of the major flight muscles is necessary to reach a thoracic temperature suitable to sustain flight. Here we show that Helicoverpa zea males exposed to an attractive pheromone blend (and in some instances to the primary pheromone component alone) started shivering earlier and took off at a lower thoracic temperature than moths subjected to other incomplete or unattractive blends. This resulted in less time spent shivering and faster heating rates. Two interesting results emerge from these experiments. First, the rate of heat generation can be modulated by different olfactory cues. Second, males detecting the pheromone blend take off at lower thoracic temperatures than males exposed to other stimuli. The take-off temperature of these males was below that for optimal power production in the flight muscles, thus generating a trade-off between rapid departure and suboptimal flight performance. Our results shed light on thermoregulatory behaviour of unrestrained moths associated with the scramble competition for access to females and suggest ecological trade-offs between rapid flight initiation and sub-optimal flight performance.

This study reports on the structure of the antennal lobe of the pigeon louse, Columbicola columbae. Anterograde staining of antennal receptor neurons revealed an antennal lobe with a few diffuse compartments, an organization distinct from the typical spheroidal glomerular structure found in the olfactory bulb of vertebrates and the antennal lobe of many other insects. This anatomical arrangement of neuronal input is somewhat reminiscent of the aglomerular antennal lobe previously reported in psyllids and aphids. As in psyllids, reports on the odor-mediated behavior of C. columbae suggest that the olfactory sense is important in these animals and indicates that a glomerular organization of the antennal lobe may not be necessary to subtend odor-mediated behaviors in all insects. The diffuse or aglomerular antennal lobe organization found in these two Paraneopteran insect orders might represent an independently evolved reduction due to similar ecological constraints., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Dioxins and dioxin-like chemicals are predominantly produced by thermal processes such as incineration and combustion at concentrations in the range of 10-100 ng of I-TEQ/kg (I-TEQ = international toxic equivalents). In this work, a new approach for the removal of dioxins from high-temperature vapor streams using facilitated supported ionic liquid membranes (SILMs) is proposed. The use of ceramic membranes containing specific ionic liquids, with extremely low volatility, for dioxin removal from incineration sources is proposed owing to their stability at very high temperatures. Supported liquid membranes were prepared by successfully immobilizing the ionic liquids tri-C(8)-C(10)-alkylmethylammonium dicyanamide ([Aliquat][DCA]) and 1-n-octyl-3-methylimidazolium dicyanamide ([Omim][DCA]) inside the porous structure of ceramic membranes. The porous inorganic membranes tested were made of titanium oxide (TiO(2)), with a nominal pore size of 30 nm, and aluminum oxide (Al(2)O(3)), with a nominal pore size of 100 nm. The ionic liquids were characterized, and the membrane performance was assessed for the removal of dioxins. Different materials (membrane pore size, type of ionic liquid, and dioxin) and different operating conditions (temperature and flow rate) were tested to evaluate the efficiency of SILMs for dioxin removal. All membranes prepared were stable at temperatures up to 200 °C. Experiments with model incineration gas were also carried out, and the results obtained validate the potential of using ceramic membranes with immobilized ionic liquids for the removal of dioxins from high-temperature vapor sources.

Background: The MUC2 mucin organizes the two mucus layers in the colon. This mucin carries a large number of O-glycans that are assumed to be attachment sites for the commensal flora found in the outer mucus layer., Methods: Single biopsies from the sigmoid colon of controls (25) and patients with inactive (13) or active (15) ulcerative colitis (UC) were collected during routine colonoscopy. The insoluble MUC2 mucin was prepared and separated by gel electrophoresis, its relative amount estimated, its O-glycans released, and glycans analyzed by novel sensitive glycomics chromatography / mass spectrometry providing information on glycan structures and relative abundances. The glycosylation pattern was related to the degree of mucosal inflammation and clinical severity of the disease., Results: The relative abundance of MUC2 showed high individual variability. Two major glycan profiles were found; a normal pattern in the control and inactive UC patients and an aberrant profile in patients with active colitis with an increase in a subset of the smaller glycans and a decrease of several complex glycans. The magnitude of this phenomenon was significantly related to both the degree of inflammation in the biopsies and also to some extent the severity of disease course. The aberrant profile was further shown to be reversible upon remission., Conclusions: In the majority of the active UC patients MUC2 mucin has an altered glycan profile as compared to inactive UC and control patients. Patients with strong alterations in the glycan pattern tended to have a more severe disease course., (Copyright © 2011 Crohn's & Colitis Foundation of America, Inc.)

Proton nuclear magnetic resonance (NMR) relaxometry was used to study the ionic mobility and levels of confinement within Nafion membranes modified by incorporation of selected ionic liquid (IL) cations. These studies were performed aiming at understanding the effect of using different types of ionic liquid cations, and their degree of incorporation, in the values of the spin-lattice relaxation times (T(1)) obtained at different values of frequency and thus detect the influence of confinement level on the ions mobility. The frequency dependence of the proton spin-lattice relaxation rate, R(1) = 1/T(1), for the modified Nafion/IL cation membranes was compared with that obtained for an unmodified Nafion membrane, allowing for distinguishing different contributions of the motions of the molecules depending on the frequency tested. The experimental R(1) results were analyzed in terms of models that consider the sum of the most effective relaxation contributions, to estimate the translational self-diffusion coefficient of the moving molecular species in the modified membranes. The stability of these membranes with temperature in terms of the spin-lattice relaxation was compared with results obtained by thermogravimetric analysis., (© 2011 American Chemical Society)

The application of membrane bioreactors (MBR) for wastewater treatment is growing worldwide due to their compactness and high effluent quality. However, membrane fouling, mostly associated to biological products, can reduce MBR performance. Therefore, it is important to monitor MBRs as close to real-time as possible to accelerate control actions for maximal biological and membrane performance. 2D-fluorescence spectroscopy is a promising on-line tool to simultaneously monitor wastewater treatment efficiency and the formation of potential biological fouling agents. In this study, 2D-fluorescence data obtained from the wastewater and the permeate of a MBR was successfully modelled using projection to latent structures (PLS) to monitor variations in the influent and effluent total chemical oxygen demand (COD). Analysis of the results also indicated that humic acids and proteins highly contributed to the measured COD in both streams. Nevertheless, this approach was not valid for other performance parameters of the MBR system (such as influent and effluent ammonia and phosphorus), which is usually characterised through a high number of analytical and operating parameters. Principal component analysis (PCA) was thus used to find possible correlations between these parameters, in an attempt to reduce the analytical effort required for full MBR characterisation and to reduce the time frame necessary to obtain monitoring results. The 3 first principal components, capturing 57% of the variance, indicated and confirmed expected relationships between the assessed parameters. However, this approach alone could not provide robust enough correlations to enable the elimination of parameters for process description (PCA loadings ≤ 0.5). Nevertheless, it is possible that the information captured by 2D-fluorescence spectroscopy could replace some of the analytical and operating parameters, since this technique was able to successfully describe influent and effluent total COD. It is thus proposed that combined modelling of 2D-fluorescence data and selected performance/operating parameters should be further explored for efficient MBR monitoring aiming at rapid process control.

The present study focuses on investigating the effects of biological compartment conditions on the transport of nitrate and perchlorate in an Ion Exchange Membrane Bioreactor (IEMB). In this hybrid process, the transport depends not only on the membrane properties but also on the biological compartment conditions. The experiments were planned according to the Plackett-Burman statistical design in order to cover a broader range of experimental conditions, under which a previously developed mechanistic transport model was not able to predict correctly the transport fluxes of the target pollutants. Using Principal Component Analysis, it was possible to identify not only the concentrations of target (nitrate and perchlorate) and of major driving counter-ion (chloride) but also those of some biomedium components (e.g. ammonia, ethanol and sulphate) as variables that affect the transport rate of micropollutants across the membrane. These conclusions are based on the loadings of the two first principal components that describe 84% of the data variance. The present study also revealed that the hydraulic retention time and the hydrodynamic conditions in the biocompartment have a minor contribution to the micropollutants transport. The results obtained are important for process optimization purposes.

Insects that are secondarily adapted to aquatic environments are able to sense odors from a diverse array of sources. The antenna of these insects, as in all insects, is the main chemosensory structure and its input to the brain allows for integration of sensory information that ultimately ends in behavioral responses. Only a fraction of the aquatic insect orders have been studied with respect to their sensory biology and most of the work has centered either on the description of the different types of sensilla, or on the behavior of the insect as a whole. In this paper, the literature is exhaustively reviewed and ways in which antennal morphology, brain structure, and associated behavior can advance better understanding of the neurobiology involved in processing of chemosensory information are discussed. Moreover, the importance of studying such group of insects is stated, and at the same time it is shown that many interesting questions regarding olfactory processing can be addressed by looking into the changes that aquatic insects undergo when leaving their aquatic environment.

The accumulation of nitrate in closed marine systems presents a problem for both the marine life and the environment. The present study, proposes the application of the ion exchange membrane bioreactor (IEMB) concept for removing nitrate from marine systems, such as aquaculture tanks or marine aquariums. The results obtained demonstrate that the IEMB was able to remove naturally accumulated nitrate from water taken from a public marine aquarium (Oceanário de Lisboa) and bioconvert it, in an isolated compartment (biocompartment), to molecular nitrogen, thus preventing secondary contamination of the treated water by microbial cells, metabolic by-products and excess of carbon source (ethanol). This system allowed for the removal of nitrate at concentrations of 251 and 380 mg/l down to below 27 mg/l exchanging it for chloride. Under the studied operating conditions, the IEMB proves to be a selective nitrate removing technology preserving the initial water composition with respect to cations, due to the Donnan exclusion effect from the membrane, and minimizing the counter diffusion of anions other than nitrate and chloride, due to the use of water with the same ionic composition in the biocompartment. This is an advantage of the IEMB concept, since the quality of the water produced would allow for the reutilisation of the treated water in the aquarium, thereby reducing both the wastewater volume and the use of fresh water.

Mercury (Hg) is the most highly toxic heavy metal, and must be removed from waterways to very low levels. Biologically mediated mercury removal is an emerging technology that has the potential to be robust, efficient and cost-effective. In this study, the impact of carbon source on the behaviour and microbial community composition of mixed microbial cultures was evaluated, and their performance was compared with a pure culture of Pseudomonas putida spi3. Glucose and acetate, two carbon sources that are commonly present in wastewaters, were chosen for this study. Distinct microbial populations were enriched with each carbon source. Glucose led to a more suitable microbial culture for Hg(2+) bioreduction that was able to reduce Hg(2+) at faster rates when compared to acetate. Furthermore, acetate consistently led to poorer process performance, irrespective of the microbial culture, possibly due to the formation of mercuric acetate complexes. It is proposed that glucose can be a more beneficial carbon source than acetate for the successful operation of Hg bioremediation systems.

Bromate is a disinfection byproduct with carcinogenic properties that has to be removed from drinking water to concentrations below 10 or 25 microg/L. This work evaluates the applicability of the ion exchange membrane bioreactor (IEMB) concept for the removal of bromate from drinking water, in situations where nitrate is also present in concentrations up to 3 orders of magnitude higher than bromate. The batch results obtained show that the biological reduction of bromate was slow and only occurring after the complete reduction of nitrate. The specific bromate reduction rates varied from 0.027 +/- 0.01 mg BrO3(-)/g(cell dry weight) x h to 0.090 mg BrO3(-)/ g(cell dry weight) x h for the studied concentrations. On the other hand, transport studies, using anion exchange membranes showed that Donnan dialysis could efficiently remove bromate from polluted waters. Therefore, the use of a dense, nonporous membrane in the IEMB system, isolates the water stream from the biological compartment, allowing for the uncoupling of the water production rate from the biological reduction rate. The IEMB system was used for the treatment of a polluted water stream containing 200 microg/L of BrO3(-) and 60 mg/L of NO3(-). The concentrations of both ions in the treated water were reduced below the recommended levels. No bromate accumulation was observed in the biocompartment of the IEMB, suggesting its complete reduction in the biofilm formed on the membrane surface contacting the biocompartment. Therefore, the IEMB has proven to be a technology able to solve specific problems associated with the removal of bromate from water streams, since it efficiently removes bromate from drinking water even in the presence of nitrate, a known competitor of bromate biological reduction, without secondary contamination of the treated water by cells or excess of carbon source.

Dioxins are highly toxic compounds that mainly originate from incineration and combustion sources. In this work, a new, simple, and efficient approach for the absorption of dioxins from gaseous streams using thermally stable ionic liquids is proposed. The absorption process of nonchlorinated and chlorinated dibenzo-p-dioxin compounds was studied in the temperature range 100-200 degrees C. Imidazolium-, ammonium-, and guanidinium-based ionic liquids were designed for this specific purpose. It was observed that imidazolium cations having long alkyl side chains exhibit the highest absorption capacities, whereas the anion dicyanoamide [DCA] possesses higher absorption capacity than other anions studied. In a typical experiment, it was found that the ionic liquid 1-n-octyl-3-methyl imidazolium dicyanoamide [C8mim][DCA] can absorb more than 14% by weight of dibenzo-p-dioxin, 2-chlorodibenzo-p-dioxin, and 1,2,3,4-tetrachlorodibenzo-p-dioxin from a gaseous stream. A process for desorption of dioxins from the ionic liquid was tested, revealing that complete desorption can be achieved under a high vacuum. Additionally, the feasibility ofthe process was examined by carrying out experiments under real operating conditions of incineration and combustion processes. The success of the method heavily relies upon the design and selection of specific ionic liquids having enhanced affinity for the aromatic compound functionality present in dioxins and, simultaneously, possessing extremely low volatility and high chemical and thermal stability.

The ion exchange membrane bioreactor (IEMB) proved to be an effective technology for the removal of nitrate and perchlorate from polluted drinking water when using a mono-anion permselective membrane such as Neosepta ACS. Aiming at reducing the cost of the system, this study evaluates the use of a lower-cost anion exchange membrane, which exhibits no preferential mono-anion permselective properties. With this purpose an Excellion I-200 membrane was tested, for the removal of anionic micropollutants, such as nitrate and perchlorate from drinking water supplies. The impact of the lower anion permselectivity of this membrane on the quality of the treated water was determined. It was demonstrated that differences between the membrane properties are responsible for the different permselectivities observed towards multi-valent and mono-valent anions. The use of Excellion I-200 resulted in a less selective removal of perchlorate and nitrate, allowing anions such as sulphate and phosphate species to be transported. When treating 3.1l/m(2)h of water contaminated with 100microg/l of perchlorate and 60mg/l of nitrate, lower removal degrees were obtained (85% of perchlorate and 88% of nitrate), compared with 96% of perchlorate and 99% of nitrate achieved with the Neosepta ACS membrane, operating under the same conditions. However, the Excellion I-200 membrane shows no target anion flux decline during a relatively long period of operation (1 month) and no secondary contamination of the treated water by the carbon source used. These characteristics are essential for a membrane to be successfully used in the IEMB system. Additionally, the selection of the membrane depends on the latter characteristics and on the water quality requirements.

Dioxins are highly toxic and ubiquitous compounds that are unintentional by-products of several chemical processes on earth. According to the earth pollutant terminology, they are next to the nuclear catastrophes. It is because of their concerns over adverse health effects, a number of countries have introduced stringent emission standards. The present review focuses on entire sources of dioxins present in the environment. They are broadly classified into four major categories such as, incineration, combustion, industrial and reservoir sources. State-of-the-art remediation technologies available for reducing dioxins formation and emission from the important sources such as, flue gas, fly ash and soil were described in detail. Further, in order to get a comprehensive perception about the dioxins subject, topics such as, dioxins transfer in the environment, their mode of action, toxicity equivalence factor, exposure and health risk assessment were highlighted in brief in the introduction. A future prospects based on the findings of the review was discussed at the end.

We investigated if Brindley's and metasternal glands are involved in the sexual behavior of Triatoma infestans. In laboratory assays, we analyzed the effect of selective occlusion of Brindley's and metasternal glands of the female (separately and together) on the behavior of males. Control assays without occlusion of glands were also performed. We quantitatively tested if such glands affect mating occurrence, the copulatory attempts of males, and the aggregation of males around a mating couple. The number of mating attempts by males did not differ between treatments, demonstrating that likelihood of males mating did not depend on which gland is occluded in the female. In the absence of any occlusion, T. infestans mated and males aggregated. The proportion of copulations and aggregation behavior of males did not differ between treatments when female's Brindley's glands were occluded. However, when metasternal glands were occluded, the proportion of mating couples decreased and males did not aggregate. We demonstrated that the metasternal glands of the female are involved in the sexual behavior of T. infestans, while Brindley's glands seem to have no effect on mating behavior. Copulation and aggregation behavior of males likely result from the eventual release of volatiles from the female's metasternal glands.

An improved method for deconvoluting complex spectral maps from bidimensional fluorescence monitoring is presented, relying on a combination of principal component analysis (PCA) and feedforward artificial neural networks (ANN). With the aim of reducing ANN complexity, spectral maps are first subjected to PCA, and the scores of the retained principal components are subsequently used as ANN input vector. The method is presented using the case study of an extractive membrane biofilm reactor, where fluorescence maps of a membrane-attached biofilm were analysed, which were collected under different reactor operating conditions. During ANN training, the spectral information is associated with process performance indicators. Originally, 231 excitation/emission pairs per fluorescence map were used as ANN input vector. Using PCA, each fluorescence map could be represented by a maximum of six principal components, thereby catching 99.5% of its variance. As a result, the dimension of the ANN input vector and hence the complexity of the artificial neural network was significantly reduced, and ANN training speed was increased. Correlations between principal components and ANN predicted process performance parameters were good with correlation coefficients in the order of 0.7 or higher.

A novel study on organic solute absorption from the vapor phase is reported. The organic solutes chosen for the absorption studies include 1,4-benzodioxane, biphenyl, xanthene, and menthol. A series of imidazolium, ammonium, and guanidinium-based ionic liquids (ILs) containing several types of anions were used as absorbents. Absorption of water vapor was also studied along with the organic solutes. Absorption studies of each organic solute were performed by using a specially devised glass apparatus at 50 degrees C. It was observed that the rate of absorption increases with time and is faster in the case of 1,4-benzodioxane (24 h). The absorption process for each organic solute with different classes of ionic liquids was studied and the results were compared with each other. Absorption values of more than 25,000 ppm were observed in some ionic liquids. Distribution ratios of organic solutes in an ionic liquid and in the vapor phase were measured and the selectivity was evaluated by using the distribution ratio values. A remarkable selectivity was observed for some ionic liquids towards a specific organic solute. Importantly, it was observed that the selectivity remained constant, even though a mixture of solute was used for the absorption study. Desorption of organic vapors from ionic liquids was successfully carried out by applying a vacuum. Further, it was observed that the same ionic liquid can be repeatedly reused several times for absorption. These studies reveal that, in future, a task-specific ionic liquid can be prepared and used for specific solute capture from the vapor phase.

More than 50 ionic liquids were prepared by using imidazolium, quaternary ammonium, and guanidinium cations and various anions. In these series, different cationic structures such as 1-benzyl-3-methylimidazolium [Bzmim]+, 1,3-dibenzylimidazolium [BzmiBz]+, 1-octyl-3-methylimidazolium [C8mim]+, 1-decyl-3-methylimidazolium [C10mim]+, tricapryl-methylammonium [Aliquat]+, benzyltriethylammonium [BzTEA]+, phenyltrimethylammonium [PhTMA]+, and dimethyldihexylguanidinium [DMG]+ were combined with anions, p-toluenesulfonate [TSA](-), dicyanoamide [DCA]-, saccharine (2-sulfobenzoic acid imide sodium salt) [SAC]-, trifluoroacetate [TFA]-, bis(trifluoromethanesulfonyl)imide [Tf2N]-, trifluoromethanesulfonate [TfO]-, and thiocyanate [SCN]-. Important physical data for these ionic liquids are collated, namely solubility in common solvents, viscosity, density, melting point and water content. Apart from the viscosity, the Newtonian and non-Newtonian behavior of these ionic liquids is also disclosed. Stability of these ionic liquids under thermal, basic, acidic, nucleophilic, and oxidative conditions was also studied. The features of the solid-liquid phase transition were analyzed, namely the glass transition temperature and the heat capacity jump associated with the transition from the non-equilibrium glass to the metastable supercooled liquid. A degradation temperature of each ionic liquid was also determined. Comparisons of the properties of various ionic liquids were made.

Picosecond time-resolved fluorescence, together with the addition of quenching agents, was employed to discriminate the fluorescence contributions of the two tryptophans of beta-lactoglobulin (Trp19 and Trp61) to the fluorescence decays of the protein. The fluorescence decays of beta-lactoglobulin at pH 3, 5 and 8 are best fitted using sums of three exponentials and show a dominant contribution (98%) of the components associated with the buried Trp19, which decays according to a double exponential function. The addition of acrylamide (0.05 M) causes an increase of the decay times associated with Trp19. This effect is observed at all pH values studied, but the effect is stronger at pH 3 and pH 5, than at pH 8. The unexpected increase of the decay times of Trp19 and the variation of the respective amplitudes were rationalized in terms of alterations of Trp19 mobility. The hindrance of Trp19 upon acrylamide binding was also monitored and supported by fluorescence anisotropy measurements.

This work evaluates the feasibility of the ion exchange membrane bioreactor (IEMB) concept for the simultaneous removal of perchlorate and nitrate from drinking water, when nitrate is present in the ppm range and perchlorate in the ppb range. The IEMB concept combines Donnan dialysis and simultaneous biological degradation of both pollutants. Membrane transport studies showed that Donnan dialysis is suitable for obtaining water with concentrations of perchlorate and nitrate below the recommended levels. However, the pollutants were accumulated in a receiving stream, thus requiring additional treatment before disposal. On the other hand, the IEMB process operated with hydraulic retention times ranging from 1.4 to 8.3h in the water compartment, proved to remove effectively perchlorate and nitrate while preserving the water composition with respect to other ions, thus avoiding secondary contamination of the treated water. For a polluted water stream containing 100 ppb of ClO(4)(-) and 60 ppm of NO(3)(-), the concentrations of both ions in the treated stream were kept below the recommended levels of 4 ppb for ClO(4)(-) and 25 ppm for NO(3)(-). The IEMB system was operated under ethanol limitation, but even under these conditions, an increase of the perchlorate and nitrate concentrations in the treated water was not observed for up to 6 days.

Thiomersal, a toxic organomercurial with a strong bactericidal effect, is the most widely used preservative in vaccine production. As a result, vaccine production wastewaters are frequently polluted with thiomersal concentrations above the European limit for mercury effluent discharges for which there is, presently, no remediation technology available. This work proposes a biotechnological process for the remediation of vaccine production wastewaters based on the biological degradation of thiomersal to metallic mercury, under aerobic conditions, by a mercury resistant bacterial strain. The kinetics of thiomersal degradation by a pure culture of Pseudomonas putida spi3 was firstly investigated in batch reactors using a thiomersal amended mineral medium. Subsequently, a continuous stirred tank reactor fed with the same medium was operated at a dilution rate of 0.05 h(-1), and the bioreactor performance and robustness was evaluated when exposed to thiomersal shock loads. In a second stage, the bioreactor was fed directly with a real vaccine wastewater contaminated with thiomersal and the culture ability to grow in the wastewater and remediate it was evaluated for dilution rates ranging from 0.022 to 0.1 h(-1).

The present study investigates the possibility of monitoring the bioproduction of a complex aroma profile with an analytical electronic aroma-sensing technique, the so-called "electronic nose", combined with a pervaporative sample enrichment method necessary to overcome the ethanol interference on the sensors' response. It presents in detail the development of a direct integrated pervaporation-electronic nose unit for a simple and fast analysis, which are key criteria for this technique to be broadly implemented. The system developed was investigated using model solutions simulating the muscatel wine must fermentation. It proved to be able to evaluate different relevant aroma compounds in solutions of varying degree of complexity, and also in the presence of ethanol, which is a major interference on the sensors' response to the aromas. The transient sensors' response was investigated in detail, revealing information for sample discrimination and reducing the analysis time. The system developed allowed a simple, fast, and selective analysis, therefore permitting a high sample throughput over time, with the possibility of fully automation.

This work aims to present a comprehensive study about the macroscopic characteristics of globular vegetable proteins, in terms of their gelling ability, by understanding their molecular behaviour, when submitted to a thermal gelling process. The gels of soy, pea and lupin proteins were characterized by rheological techniques. Gelation kinetics, mechanical spectra, as well as the texture of these gels were analyzed and compared. Additionally, capillary viscometry, steady-state fluorescence and fluorescence anisotropy were used to monitor the structural changes induced by the thermal denaturation, which constitutes the main condition for the formation of a gel structure. Based on these techniques it was possible to establish a relationship between the gelling ability of each protein isolate and their structural resistance to thermal unfolding, enabling us to explain the weakest and the strongest gelling ability observed for lupin and soy proteins isolates, respectively.

Using the example of a membrane-supported biofilm reactor for industrial effluent treatment, different non-mechanistic approaches for the modelling of complex bioprocesses are presented and evaluated. The models were obtained employing feedforward artificial neural network analysis for the association of process operation with process performance. Three modelling approaches are discussed, i.e. autonomous static (AS) modelling, non-autonomous static (NAS) modelling, as well as a novel approach termed dynamic modelling with embedding of artificial neural network inputs. They are compared with regard to their ability to infer process performance for two different pollutant case studies, employing 1,2-dichloroethane and 3-chloro-4-methylaniline, respectively. The suitability of the different approaches was found to be strongly dependent on process configuration. Especially in configurations where lag times are apparent, the dynamic modelling approach was found to be superior, and process performance prediction was found to be strongly dependent on the history of process operation.

We report on the molecular interactions between room-temperature ionic liquids (RTILs) and Nafion and PDMS membranes, proving that in contact with these polymers RTILs behave like electrolytes rather than solvents.

A method for non-mechanistic and non-linear modelling of complex biological processes is presented, using the example of the extractive membrane bioreactor (EMB). The model is based on artificial neural networks (ANN), which are able to predict the state of the process from a combination of reactor operational parameters and natural fluorescence fingerprints. Current as well as historic process operation is included in the ANN input vector, in order to account for lag-times within the reactor system and for biofilm dynamics that are dependent on process history. The model is especially relevant for practitioners, as it does not require assumptions on underlying process mechanisms, and it relies on routinely available operational data and on an easy-to-install, non-invasive, in-situ, on-line monitoring method. Moreover, it focuses on the prediction of overall process performance parameters, which are of immediate relevance in practice. The developed model was able to predict the process state very well. Sensitivity analysis revealed that the main impact on process performance stems from process operation rather than the physiological state of the biological culture, and that in the EMB configuration employed process operation history decisively impacts on the process outcome.

Biological treatment processes allow for the effective elimination of anionic micropollutants from drinking water. However, special technologies have to be implemented to eliminate the target pollutants without changing water quality, either by adding new pollutants or removing essential water components. Some innovative technologies that combine the use of membranes with the biological degradation of ionic micropollutants in order to minimize the secondary contamination of treated water include pressure-driven membrane bioreactors, gas-transfer membrane bioreactors and ion exchange membrane bioreactors.

Vaccine production effluents are strongly polluted with thiomersal, a highly toxic organomercurial compound, for which there is presently no remediation technology available. This work describes a new remediation process based on the extraction of thiomersal from the wastewater to a biological compartment, where it is degraded by a microbial strain. The selective extraction of thiomersal is achieved by using an ionic liquid immobilized in a porous membrane. In the biological compartment, thiomersal is degraded to metallic mercury, under aerobic conditions, by a Pseudomonas putida strain. The utilization of ionic liquids in supported liquid membranes for thiomersal transport, and the kinetics of thiomersal biodegradation by a Pseudomonas putida strain are presented and discussed.

Natural fluorescence as a method to monitor biofilm processes was studied, using the example of an extractive membrane bioreactor for the degradation of 3-chloro-4 methylaniline and 1,2-dichloroethane. Non-invasive, on-line, in-situ 2D fluorometry monitoring was employed to elicit biofilm process status. The fluorescence fingerprints were deconvoluted in a pattern recognition approach using artificial neural networks (ANN) through association with key process performance parameters.

The possibility of using room-temperature ionic liquids (RTILs) in bulk (nonsupported) and supported liquid membranes for the selective transport of organic molecules is demonstrated. A systematic selective transport study, in which 1,4-dioxane, propan-1-ol, butan-1-ol, cyclohexanol, cyclohexanone, morpholine, and methylmorpholine serve as a model seven-component mixture of representative organic compounds, and in which four RTILs based on the 1-n-alkyl-3-methylimidazolium cation (n-butyl, n-octyl, and n-decyl) are used together with the anions PF(6)(-) or BF(4)(-), immobilized in five different supporting membranes, confirms that the combination of the selected RTILs with the supporting membranes is crucial to achieve good selectivity for a specific solute. The use of the RTIL 1-n-butyl-3-methylimidazolium hexafluorophosphate, immobilized in a polyvinylidene fluoride membrane, allows an extremely highly selective transport of secondary amines over tertiary amines (up to a 55:1 ratio). The selective transport of a given solute through the RTIL/membrane system results from the high partitioning of the solute to the liquid membrane phase which, in the case of amines, is rationalized mainly by the formation of a preferential substrate/H[bond]C(2) hydrogen bonding to the imidazolium cation.

This work discusses the feasibility of using the electronic nose for the on-line and real-time monitoring of the production of a complex aroma profile during a bioconversion process. As a case study, the formation of the muscatel aroma during the wine-must fermentation was selected. During wine-must fermentation, aroma compounds responsible for the organoleptic character are produced in the ppm range, while simultaneously one of the main metabolic products, ethanol, is produced in much higher quantities (up to 10% wt). Because the sensors of the electronic nose array are cross-selective to different volatile compounds, it was investigated in detail how far the electronic nose was able to evaluate the aroma profile along the fermentation. This article discusses and evaluates subsequently the integration of a membrane separation process-organophilic pervaporation-for selectively enriching aroma compounds relative to ethanol, to improve sample discrimination., (Copyright 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 632-640, 2002; DOI 10.1002/bit.10141)

An ion exchange membrane bioreactor (IEMB), consisting of a monoanion permselective membrane dialyzer coupled to a stirred anoxic vessel with an enriched mixed denitrifying culture, has been studied for nitrate removal from drinking water. The influence of nitrate and chloride concentrations on the selectivity of nitrate transport in the IEMB process was investigated. With appropriate dosing of chloride ions to the IEMB biocompartment, it was possible to regulate the net bicarbonate flux in the system, thus maintaining the bicarbonate concentration in the treated water at the desired level. The latter was not possible to achieve in Donnan dialysis, operated as a single process in which, besides the lower nitrate removal efficiency found, bicarbonate was co-extracted together with nitrate from the polluted water stream. Residual carbon source (ethanol) and nitrite were not detected in the treated water produced in the IEMB system. With a concentration of nitrate in the polluted water three times higher than the maximum contaminant level of 50 mg L(-1) allowed, the IEMB process was successfully operated for a period of 1 month before exceeding this limit.

Non-porous membranes with the selective layer consisting of hydrophilic or hydrophobic polymers have been applied for the quantitative and selective recovery of solutes with different physico-chemical properties from a room-temperature ionic liquid, ([bmim][PF6]).