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Upon light irradiation, photochromic materials exhibit drastic changes in absorbance in addition to molecular and mechanical changes. In this study, we demonstrated optical trapping of photochromic microcrystals in a double fiber optical tweezers system combined with two external lights for photoisomerization and observed changes in the trapping force by photoisomerization. In situ photoisomerizations of the single crystal trapped in the system were performed thrice revealing a reversible change in the trapping force. The trapping stiffness for the colored crystal was one-third of that for the decolorized crystal in the axial direction, whereas almost no difference was observed in the transverse direction. Furthermore, based on the intermittent motion and asymmetry of the positional distribution of the trapped crystals, we inferred that the motion includes transitions through multiple stable sites, and the ease of the transition is related to the isomerization state of the crystals. Such switching of optical trapping indicates the possibility of revealing the physical properties of trapped materials through trapping schemes, and the nonlinearity in the trapping is also expected to be applied to advanced computing with physical phenomena. [ABSTRACT FROM AUTHOR]

Presents a study on the microstructural and nonlinear optical properties of thin silica-titania sol-gel films doped with different concentrations of lead-sulfide (PbS). Experimental procedure; Results and discussion; Conclusions.

Because aquatic insects use histamines as neurotransmitters, adverse impacts on aquatic insects living in aquatic environments that receive antihistamines with wastewater effluent are plausible. In this study, we exposed damselfly larvae to low concentrations of two commonly used antihistamines (Hydroxyzine and Fexofenadine, 360±42 and 2200±43 ng l−1, respectively), and recorded damselfly larvae behavior before and after exposure. Further, after the second set of behavioral assays was performed, we quantified bioconcentration of the antihistamines in the damselfly bodies. Our results showed significant changes in damselfly behavior following antihistamine exposure. After Hydroxyzine exposure, the damselfly larvae became less active, and they showed reduced fleeing response (i.e. increased boldness) after being exposed to Fexofenadine, the latter also being significantly different from the non-exposed (control) individuals. Further, we found high levels of bioconcentration in the damselflies; Hydroxyzine showed an average bioconcentration factor (BCF) of 2000. As such, our results indicate that low concentrations of antihistamines can have sub-lethal effects on aquatic insects manifested as behavioral changes, and that bioconcentration of these substances can be high. Therefore, the need to investigate the impact of emergent aquatic contaminants also on aquatic insects, and on behaviors that are of ecological importance, is further highlighted. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report on the optical characterizations of erbium-doped yttrium alumino-borate glassy thin films prepared by the polymeric precursor and sol–gel routes and the spin-coating technique. High quality planar waveguides were produced by a multilayer processing of Y1− x Er x Al3(BO3)4 compositions with x =0.02, 0.05, 0.10, 0.30, and 0.50. Their optical properties were investigated using transmission, photoluminescence, and m-lines spectroscopy, whereas high resolution scanning electron microscopy (HR-SEM) was applied to check film thickness and surface homogeneity. The refractive indices determined from transmission and m-lines spectroscopy are in good agreement just like the film thickness measured by HR-SEM and transmission spectroscopy. We observed low propagation losses, together with efficient photoluminescence emission for polymeric precursor thin films, involving low cost and environment friendly reactants. [Copyright &y& Elsevier]

Abstract: In this work, a sol–gel route was used to prepare Y0.9Er0.1Al3(BO3)4 glassy thin films by spin-coating technique looking for the preparation and optimization of planar waveguides for integrated optics. The films were deposited on silica and silicon substrates using stable sols synthesized by the sol–gel process. Deposits with thicknesses ranging between 520 and 720nm were prepared by a multi-layer process involving heat treatments at different temperatures from glass transition to the film crystallization and using heating rates of 2°C/min. The structural characterization of the layers was performed by using grazing incidence X-ray diffraction and Raman spectroscopy as a function of the heat treatment. Microstructural evolution in terms of annealing temperatures was followed by high resolution scanning electron microscopy and atomic force microscopy. Optical transmission spectra were used to determine the refractive index and the film thicknesses through the envelope method. The optical and guiding properties of the films were studied by m-line spectroscopy. The best films were monomode with 620nm thickness and a refractive index around 1.664 at 980nm wavelength. They showed good waveguiding properties with high light-coupling efficiency and low propagation loss at 632.8 and 1550nm of about 0.88dB/cm. [Copyright &y& Elsevier]

Optically active Y2-xErxTi2O7 (YETO) thin films have been successfully deposited using the aerosol–gel process. The effects of post-deposition rapid thermal annealing and conventional thermal annealing heat-treatments have been investigated. The corresponding thin film microstructure is described and discussed in terms of crystallisation degree, mean crystallite size, and porosity. Strong photoluminescence (PL) at 1.53 μm is observed under 980 nm excitation. PL properties are found to depend closely on the film crystallisation degree. PL emission spectra exhibit sharp peaks for crystalline films and a wide band for amorphous ones. PL decay curves are also very closely related to the film microstructure and the corresponding lifetimes range between 2 and 7 ms for a similar erbium concentration. [Copyright &y& Elsevier]

In this study, we were able to separate buildings with high and low prevalence of sick building syndrome (SBS) using principal component analysis. The prevalence of SBS was defined by the presence of at least one typical skin, mucosal and general (headache and fatigue) symptom. Data from the Swedish Office Illness Study describing the presence and level of chemical compounds in outdoor, supply, and room air, respectively, were evaluated together with information about the buildings in six models. When all data were included the most complex model was able to separate 71% of the high prevalence buildings from the low prevalence buildings. The most important variable that separates the high prevalence buildings from the low prevalence buildings was a more frequent occurrence or a higher concentration of compounds with shorter retention time in the high prevalence buildings. Elevated relative humidity in supply and room air and higher levels of total volatile organic compounds in outdoor and supply air were more common in high prevalence buildings. Ten building variables also contributed to the separation of the two classes of low and high prevalence buildings. Principal component analysis (PCA) can be a tool to evaluate variables that may cause Sick Building Syndrome. The method is promising, but more development of the technique, and a deeper understanding of how different type and specificity of input variables influence the modeling result are needed before PCA can be used as a practical tool. [ABSTRACT FROM AUTHOR]

Thin arsenic trisulfide films were deposited by thermal evaporation and thermally activated silver diffusion into these films was studied. UV–vis transmission and Rutherford backscattering spectrometry (RBS) was used for characterization of film property changes with Ag incorporation. The straightforward analysis proposed by Swanepoel, which allows determination of the dispersion relation and the film thickness from the optical transmission spectrum, was extended and applied to the chalcogenide thin films. RBS shows that silver diffusion mechanism depends strongly on an eventual annealing between the chalcogenide and silver deposition step. Without annealing the silver diffusion takes place by exchange between silver and arsenic atoms whereby sulfur atoms remain stationary, and arsenic accumulation occurs at the surface. For annealed samples silver diffuses without changing the film stoichiometry. In this case, the diffusion is much slower and the profile is more step-like. The possibility of using this technique for channel waveguide fabrication is demonstrated. [Copyright &y& Elsevier]

Thin silica-titania films doped with CdS and PbS nanocrystals have been prepared by the sol-gel route. Their nonlinear properties have been studied using the techniques of degenerated four-wave mixing and m-lines with picosecond (ps) and nanosecond laser pulses. Depending on wavelength, doping level, and laser pulse duration, high negative nonlinearity was found for CdS-doped (n[sub 2] = -2 x 10[sup -8] cm[sup 2] per kW) and PbS-doped films (-10[sup -10] to -2 x 10[sup -7] cm[sup 2] per kW). The response time of the nonlinearity was below 35 ps. Saturation of the nonlinearity was observed. Straight, monomode channel waveguides have been fabricated on these films. The influence of MIE-scattering due to the nanoparticles is investigated. [ABSTRACT FROM AUTHOR]

• Water temperature significantly affects biotransformation of pharmaceuticals in fish. • Biologically active metabolites can accumulate in fish without being present in water. • Relative importance of metabolic pathways in fish can differ from mammalian models. • Ability to biotransform pharmaceuticals can differ between macroinvertebrate species. Pharmaceutically active compounds (PhACs) have been shown to accumulate in aquatic and riparian food-webs. Yet, our understanding of how temperature, a key environmental factor in nature, affects uptake, biotransformation, and the subsequent accumulation of PhACs in aquatic organisms is limited. In this study, we tested to what extent bioconcentration of an anxiolytic drugs (temazepam and oxazepam) is affected by two temperature regimes (10 and 20 °C) and how the temperature affects the temazepam biotransformation and subsequent accumulation of its metabolite (oxazepam) in aquatic organisms. We used European perch (Perca fluviatilis) and dragonfly larvae (Sympetrum sp.), which represent predator and prey species of high ecological relevance in food chains of boreal and temperate aquatic ecosystems. Experimental organisms were exposed to target pharmaceuticals at a range of concentrations (0.2–6 µg L−1) to study concentration dependent differences in bioconcentration and biotransformation. We found that the bioconcentration of temazepam in perch was significantly reduced at higher temperatures. Also, temperature had a strong effect on temazepam biotransformation in the fish, with the production and subsequent accumulation of its metabolite (oxazepam) being two-fold higher at 20 °C compared to 10 °C. In contrast, we found no temperature dependency for temazepam bioconcentration in dragonfly larvae and no detectable biotransformation of the parent compound that would result in measurable concentrations of oxazepam in this organism. Our results highlight that while organisms may share the same aquatic ecosystem, their exposure to PhACs may change differently across temperature gradients in the environment. [ABSTRACT FROM AUTHOR]

Vibrational sum-frequency generation (VSFG) was used to investigate the conformational changes in self-assembled monolayers (SAMs) of (1-mercaptoundec-11-yl) hexa(ethylene glycol) monomethylether (EG6-OMe) on gold when exposed to liquid water. VSFG spectra of the EG6-OMe SAMs were recorded before, during, and after exposure of the films to water and after a subsequent evacuation step. While in contact with water the entire ethylene glycol chains are found in a random, solvated state, after removal from the fluid water molecules remain absorbed only at the terminal groups of the film giving rise to distinct conformational changes. After evacuation, the structure of the EG6-OMe SAM reverts to its original state, indicating that water has been removed from the monolayer. Our findings support recent ab initio calculations and Monte Carlo simulations on the interaction of ethylene glycol-terminated monolayers with water. [ABSTRACT FROM AUTHOR]

Environmental pollution by Pharmaceuticals is increasingly recognized as a major threat to aquatic ecosystems worldwide. A variety of Pharmaceuticals enter waterways by way of treated waste water effluents and remain biochemically active in aquatic systems. Several ecotoxicological studies have been done, but generally, little is known about the ecological effects of Pharmaceuticals. Here we show that a benzodiazepine anxiolytic drug (oxazepam) alters behavior and feeding rate of wild European perch (Perca fluviatilis) at concentrations encountered in effluent-influenced surface waters. Individuals exposed to water with dilute drug concentrations (1.8 micrograms liter-1) exhibited increased activity, reduced sociality, and higher feeding rate. As such, our results show that anxiolytic drugs in surface waters alter animal behaviors that are known to have ecological and evolutionary consequences. [ABSTRACT FROM AUTHOR]

• 62 pharmaceuticals accumulated across tissues in a wild marine fish. • Differential accumulation across internal tissues and plasma. • Highest number of pharmaceuticals detected in liver > brain > plasma > muscle. • Pharmaceutical concentrations highest in plasma > liver > brain > muscle. • Compositional differences in accumulation across tissues. To date, the presence of pharmaceuticals has been extensively documented across a wide range of aquatic systems and biota. Further, substantial progress has been made in transitioning from laboratory assessments of pharmaceutical fate and effects in fish to in situ assessments of exposure and effects; however, certain research areas remain understudied. Among these is investigation of differential accumulation across multiple internal tissues in wild marine fish beyond the species commonly sampled in laboratory and freshwater field settings. This study examined the presence of pharmaceuticals across four tissues (plasma, muscle, brain, and liver) in a wild marine fish, bonefish (Albula vulpes), throughout coastal South Florida, USA. Differential accumulation across tissues was assessed for the number and concentration, identity, and composition of accumulated pharmaceuticals by sampling 25 bonefish and analyzing them for 91 pharmaceuticals. The concentration of pharmaceuticals was highest in plasma > liver > brain > muscle, while the number of pharmaceuticals was highest in liver > brain > plasma > muscle. The identity of detected pharmaceuticals was tissue specific, and there was an inverse relationship between the number of detections for each pharmaceutical and its log K ow. The composition of pharmaceuticals was tissue specific for both pharmaceutical presence/absence and concentration. Across all tissues, the greatest similarity was between brain and liver, which were more similar to plasma than to muscle, and muscle was the most distinct tissue. For tissue compositional variability, muscle was the most diverse in accumulated pharmaceuticals, while plasma, brain, and liver were similarly variable. With the highest concentrations in plasma and highest number in liver, and documented variability in accumulated pharmaceuticals across tissues, our results highlight the importance of tissue selection when surveying exposure in wild fish, suggesting that multi-tissue analysis would allow for a more comprehensive assessment of exposure diversity and risk of adverse effects. [Display omitted] [ABSTRACT FROM AUTHOR]

Ozonation to achieve removal of pharmaceuticals from wastewater effluents, with pH values in the upper and lower regions of the typical range for Swedish wastewater, was investigated. The main aim was to study the effects of varying pH values (6.0 and 8.0), and if small additions of H2O2 prior to ozone treatment could improve the removal and lower the reaction time. The effluents studied differed in their chemical characteristics, particularly in terms of alkalinity (65.3-427 mg·l-1 HCO3-), COD (18.2-41.8 mg·l-1), DOC (6.9-12.5 mg·l-1), ammonium content (0.02-3.6 mg·l-1) and specific UV absorbance (1.78-2.76 l.mg-1.m-1). As expected, lower ozone decomposition rates were observed in the effluents at pH 6.0 compared to pH 8.0. When pH 8.0 effluents were ozonated, a higher degree of pharmaceutical removal occurred in the effluent with low specific UV absorbance. For pH 6.0 effluents, the removal of pharmaceuticals was most efficient in the effluent with the lowest organic content. The addition of H2O2 had no significant effect on the quantitative removal of pharmaceuticals but enhanced the ozone decomposition rate. Thus, H2O2 addition increased the reaction rate. In practice, this will mean that the reactor volume needed for the ozonation of wastewater effluents can be reduced. [ABSTRACT FROM AUTHOR]

Pharmaceutical uptake involves processes that vary across aquatic systems and biota. However, single studies examining multiple environmental compartments, microhabitats, biota, and exposure pathways in mesoconsumer fish are sparse. We investigated the pharmaceutical burden in bonefish (Albula vulpes), pathways of exposure, and estimated exposure to a human daily dose. To evaluate exposure pathways, the number and composition of pharmaceuticals across compartments and the bioconcentration in prey and bonefish were assessed. To evaluate bioaccumulation, we proposed the use of a field-derived bioaccumulation factor (fBAF), due to variability inherent to natural systems. Exposure to a human daily dose was based on bonefish daily energetic requirements and consumption rates using pharmaceutical concentrations in prey. Pharmaceutical number and concentration were highest in prey, followed by bonefish, water and sediment. Fifteen pharmaceuticals were detected in common among bonefish, prey, and water; all of which bioconcentrated in prey and bonefish, and four bioaccumulated in bonefish. The composition of detected pharmaceuticals was compartment specific, and prey were most similar to bonefish. Bonefish were exposed to a maximum of 1.2 % of a human daily dose via prey consumption. Results highlight the need for multicompartment assessments of exposure and consideration of prey along with water as a pathway of exposure. [Display omitted] • Pharmaceuticals detected in water, sediment, prey, and a mesoconsumer fish. • Number and concentration were distinct across compartments and highest in prey. • Composition of pharmaceuticals was most similar between prey and bonefish. • Consumption of prey may be a potential pathway of pharmaceutical exposure. • Exposure to bonefish was up to 1.2 % of a human daily dose based on prey consumption. [ABSTRACT FROM AUTHOR]

Abstract: The presence of pharmaceuticals in the aquatic environment, and the concerns for negative effects on aquatic organisms, has gained increasing attention over the last years. As ecotoxicity data are lacking for most active pharmaceutical ingredients (APIs), it is important to identify strategies to prioritise APIs for ecotoxicity testing and environmental monitoring. We have used nine previously proposed prioritisation schemes, both risk- and hazard-based, to rank 582 APIs. The similarities and differences in overall ranking results and input data were compared. Moreover, we analysed how well the methods ranked seven relatively well-studied APIs. It is concluded that the hazard-based methods were more successful in correctly ranking the well-studied APIs, but the fish plasma model, which includes human pharmacological data, also showed a high success rate. The results of the analyses show that the input data availability vary significantly; some data, such as logP, are available for most API while information about environmental concentrations and bioconcentration are still scarce. The results also suggest that the exposure estimates in risk-based methods need to be improved and that the inclusion of effect measures at first-tier prioritisation might underestimate risks. It is proposed that in order to develop an adequate prioritisation scheme, improved data on exposure such as degradation and sewage treatment removal and bioconcentration ability should be further considered. The use of ATC codes may also be useful for the development of a prioritisation scheme that includes the mode of action of pharmaceuticals and, to some extent, mixture effects. [Copyright &y& Elsevier]

Abstract: Z-cut KTP single crystals were irradiated with 300keV He- and 1MeV Li-ions at fluences between 1×1015 and 2×1016 cm−2. The irradiation decreases the refractive index in the depth region of high nuclear energy deposition and, as a consequence, a waveguide barrier is formed. The damage accumulation was monitored using Rutherford backscattering spectrometry (RBS). The characterization of the waveguide was carried out by optical transmission and m-line spectroscopy. The difference of the refractive index between the waveguide and the barrier increases with increasing ion fluence. The maximum difference is reached at a fluence, which is noticeable higher than the amorphization fluence measured by RBS. The number of displacements per atom, which are necessary to obtain identical reductions of the barrier refractive index is higher for lower ion masses. The results show that the refractive index can be purposefully adjusted by varying the ion mass and the ion fluence. [Copyright &y& Elsevier]

Abstract: Yttrium titanate (YTO) thin films doped with rare earth elements have been deposited using the aerosol–gel process. The up-conversion emission (UPE) of films doped with erbium and/or thulium has been studied with respect to the film crystallization degree and rare earth concentration. The effects of ytterbium codoping have been considered as well. Mechanisms that control UPE of YTO films are discussed with respect to the experimental conditions. It is shown that films, which selectively emit in the blue (1G4→3H6 transition of thulium ions), green (2H11/2→4I15/2 and 4S3/2→4I15/2 transitions of erbium ions), or red (4F9/2→4I15/2 transition of erbium ions), can readily be achieved. [Copyright &y& Elsevier]

Aerosol-gel process is a deposition method based on the sol-gel polymerization of a liquid film produced from an ultrasonically sprayed aerosol. This process offers an attractive alternative for the deposition of photocurable SiO2-TiO2 ORMOSIL films. 3-(trimethoxysilyl) propylmethacrylate and tetraisopropyl-orthotitanate complexed with methacrylic acid were used as sol-gel precursors. Doping with a terbium:sulphosalicylic acid complex was also studied to test the deposition of spectroscopically active photocurable films. FTIR spectroscopy has been used to study the precursor solutions and ORMOSIL films. It is shown that titanium precursor incorporation enhances the solution reactivity, which yields optical quality thin films. Photopolymerization and photoluminescence properties of the films are reported and discussed with respect to the experimental parameters. The results allow envisaging the UV-imprinting fabrication of Aerosol-gel-derived active waveguides. [ABSTRACT FROM AUTHOR]

Photocurable SiO2–TiO2 ORMOSIL films have been deposited using the aerosol–gel process. 3-(trimethoxysilyl) propylmethacrylate and tetraisopropyl-orthotitanate complexed with methacrylic acid were used as sol–gel precursors. Doping with a terbium:sulphosalicylic acid complex was also studied to test the deposition of optically active photocurable films. Photopolymerization and photoluminescence properties of the films are reported. The results demonstrate the potential of UV-writing of aerosol–gel deposited active thin films. [Copyright &y& Elsevier]

Three in vivo techniques were evaluated in terms of their suitability for determination of the apparent ileal amino acid digestibility (AID) of protein sources for piglets. The techniques were: ileo-rectal anastomosis (IRA), cannulation at the distal ileum and a slaughter technique. A standard diet and three diets in which 20% of the standard diet was substituted with either skim milk powder (SMP), fish meal or roasted full-fat soya beans (FFS) were used. Piglets were weaned at 21 days of age, and the respective diets were fed in 24 equal hourly portions per day from days 29-37. Ileal digesta was collected from day 33-37 in IRA and cannulated piglets. Piglets used for the slaughter technique were killed at 37 days of age and ileal digesta was collected. Chromium III oxide was used as an indigestible marker with all three techniques. Although AID means did not differ (p > 0.05) between the different techniques, the cannulation technique resulted in the lowest variation (standard error of the mean) of all treatments (8.2 vs 13.7 and 14.1 for the slaughter and IRA-techniques respectively). AID means obtained using the cannula technique were 1.8 percentage units higher for the SMP diet than values obtained using the other techniques (83.2 versus 81.4%), and up to 9.3 percentage units higher for the FFS diet (75.4 versus 66.1%). Growth data suggested that the cannulation technique caused less trauma for the piglets than the IRA-technique. IRA-piglets had not yet regained their initial weaning weight by 37 days of age, while the other piglets gained weight over the trial period. The cannulation technique is the most attractive method for use with piglets in terms of the lower variation in digestibility values. Practical aspects such as ease of handling and sampling, surgical trauma and piglet stress, are also important and contribute to the selection of the cannula technique as the most appropriate. [ABSTRACT FROM AUTHOR]

Most research on pharmaceutical presence in the environment to date has focused on smaller scale assessments of freshwater and riverine systems, relying mainly on assays of water samples, while studies in marine ecosystems and of exposed biota are sparse. This study investigated the pharmaceutical burden in bonefish (Albula vulpes), an important recreational and artisanal fishery, to quantify pharmaceutical exposure throughout the Caribbean Basin. We sampled 74 bonefish from five regions, and analyzed them for 102 pharmaceuticals. We assessed the influence of sampling region on the number of pharmaceuticals, pharmaceutical assemblage, and risk of pharmacological effects. To evaluate the risk of pharmacological effects at the scale of the individual, we proposed a metric based on the human therapeutic plasma concentration (H T PC), comparing measured concentrations to a threshold of 1/3 the H T PC for each pharmaceutical. Every bonefish had at least one pharmaceutical, with an average of 4.9 and a maximum of 16 pharmaceuticals in one individual. At least one pharmaceutical was detected in exceedance of the 1/3 H T PC threshold in 39% of bonefish, with an average of 0.6 and a maximum of 11 pharmaceuticals exceeding in a Key West individual. The number of pharmaceuticals (49 detected in total) differed across regions, but the risk of pharmacological effects did not (23 pharmaceuticals exceeded the 1/3 H T PC threshold). The most common pharmaceuticals were venlafaxine (43 bonefish), atenolol (36), naloxone (27), codeine (27), and trimethoprim (24). Findings suggest that pharmaceutical detections and concentration may be independent, emphasizing the need to monitor risk to biota regardless of exposure diversity, and to focus on risk quantified at the individual level. This study supports the widespread presence of pharmaceuticals in marine systems and shows the utility of applying the H T PC to assess the potential for pharmacological effects, and thus quantify impact of exposure at large spatial scales. [Display omitted] • Pharmaceuticals were detected in all fish from Caribbean coastal ecosystems. • 49 of 102 pharmaceuticals detected and 23 exceeded the 1/3 H T PC. • 39% of fish had pharmaceuticals at concentrations capable of pharmacological effects. • Number of detections and pharmaceutical concentrations varied across regions. • Exposure to pharmacologically active concentrations was unrelated to detections. [ABSTRACT FROM AUTHOR]

An increasing number of short-term laboratory studies on fish reports behavioral effects from exposure to aquatic contaminants or raised carbon dioxide levels affecting the GABA A receptor. However, how such GABAergic behavioral modifications (GBMs) impact populations in more complex natural systems is not known. In this study, we induced GBMs in European perch ( Perca fluviatilis ) via exposure to a GABA agonist (oxazepam) and followed the effects on growth and survival over one summer (70 days) in replicated pond ecosystems. We hypothesized that anticipated GBMs, expressed as anti-anxiety like behaviors (higher activity and boldness levels), that increase feeding rates in laboratory assays, would; i) increase growth and ii) increase mortality from predation. To test our hypotheses, 480 PIT tagged perch of known individual weights, and 12 predators (northern pike, Esox lucius ) were evenly distributed in 12 ponds; six control (no oxazepam) and six spiked (15.5 ± 4 μg l − 1 oxazepam [mean ± 1 S.E.]) ponds. Contrary to our hypotheses, even though perch grew on average 16% more when exposed to oxazepam, we found no significant difference between exposed and control fish in growth (exposed: 3.9 ± 1.2 g, control: 2.9 ± 1 g [mean ± 1 S.E.], respectively) or mortality (exposed: 26.5 ± 1.8 individuals pond − 1 , control: 24.5 ± 2.6 individuals pond − 1 , respectively). In addition, we show that reduced prey capture efficiency in exposed pike may explain the lack of significant differences in predation. Hence, our results suggest that GBMs, which in laboratory studies impact fish behavior, and subsequently also feeding rates, do not seem to generate strong effects on growth and predation-risk in more complex and resource limited natural environments. [ABSTRACT FROM AUTHOR]

Pharmaceuticals derived from manufacturing and human consumption contaminate surface waters worldwide. To what extent such pharmaceutical contamination accumulates and disperses over time in different compartments of aquatic food webs is not well known. In this study we assess to what extent five pharmaceuticals (diphenhydramine, oxazepam, trimethoprim, diclofenac, and hydroxyzine) are taken up by fish (European perch) and four aquatic invertebrate taxa (damselfly larvae, mayfly larvae, waterlouse, and ramshorn snail), by tracing their bioconcentrations over several months in a semi-natural large-scale (pond) system. The results suggest both significant differences among drugs in their capacity to bioaccumulate and differences among species in uptake. While no support for in situ uptake of diclofenac and trimethoprim was found, oxazepam, diphenhydramine, and hydroxyzine were detected in all analyzed species. Here, the highest bioaccumulation factor (tissue:water ratio) was found for hydroxyzine. In the food web, the highest concentrations were found in the benthic species ramshorn snail and waterlouse, indicating that bottom-living organism at lower trophic positions are the prime receivers of the pharmaceuticals. In general, concentrations in the biota decreased over time in response to decreasing water concentrations. However, two interesting exceptions to this trend were noted. First, mayfly larvae (primarily grazers) showed peak concentrations (a fourfold increase) of oxazepam, diphenhydramine, and hydroxyzine about 30 days after initial addition of pharmaceuticals. Second, perch (top-predator) showed an increase in concentrations of oxazepam throughout the study period. Our results show that drugs can remain bioavailable for aquatic organism for long time periods (weeks to months) and even re-enter the food web at a later time. As such, for an understanding of accumulation and dispersion of pharmaceuticals in aquatic food webs, detailed ecological knowledge is required. [ABSTRACT FROM AUTHOR]

Production and human consumption of pharmaceuticals result in contamination of surface waters worldwide. Little is known about the long-term (i.e., over decades) fate of pharmaceuticals in aquatic systems. Here, we show that the most prescribed anxiolytic in Sweden (oxazepam) persists in its therapeutic form for several decades after being deposited in a large freshwater lake. By comparing sediment cores collected in 1995 and 2013, we demonstrate that oxazepam inputs from the early 1970s remained in the sediments until sampling in 2013, despite in situ degradation processes and sediment diagenesis. In laboratory and pond experiments, we further reveal that therapeutic forms of oxazepam can persist over several months in cold (5 °C) lake water free from UV light. We conclude that oxazepam can persist in lakes over a time scale much longer than previously realized and that levels can build up in lakes due to both a legacy of past inputs and a growing urban population. [ABSTRACT FROM AUTHOR]

The application of treated sewage sludge on farmland is a suggested method for recycling nutrients and reducing demand for commercial fertilizer. However, sludge needs to be safe from possible contaminants which can cause acute and long-term health and environmental problems. Residual pharmaceuticals and organic contaminants are mentioned as emerging threats since wastewater treatment plants are not designed to degrade these substances. The aim of this study was to screen and evaluate the presence, and reduction, of pharmaceuticals and polycyclic aromatic hydrocarbons (PAHs) during anaerobic digestion of mixed primary and waste-activated sludge at 35, 55 and 60 °C and during pasteurization at 70 °C. The study showed the difficulty of analysing pharmaceutical compounds in low concentrations in the sludge matrix. No general reduction of these compounds was seen during treatment, but for individual substances some reduction occured. The PAHs were generally not reduced during digestion or pasteurization, but for three substances (indeno[1,2,3-cd]pyrene and dibenzo[a,h]anthracene (analysed together) and benzo[g,h,i]perylene) reduction (up to 60%) during digestion was seen. Digestion at 35 and 55 WC resulted in about the same order of reduction of the three individual PAHs, which was higher than for digestion at 60 °C. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the characterization of single-mode waveguides for 980 and 1550 nm wavelengths. High quality planar waveguide structure was fabricated from Y1− x Er x Al3(BO3)4 multilayer thin films with x =0.02, 0.05, 0.1, 0.3, and 0.5, prepared through the polymeric precursor and sol-gel methods using spin-coating. The propagation losses of the planar waveguides varying from 0.63 to 0.88 dB/cm were measured at 632.8 and 1550 nm. The photoluminescence spectra and radiative lifetimes of the Er3+ 4I13/2 energy level were measured in waveguiding geometry. For most samples the photoluminescence decay was single exponential with lifetimes in between 640 μs and 200 μs, depending on the erbium concentration and synthesis method. These results indicate that Er doped YAl3(BO3)4 compounds are promising for low loss waveguides. [Copyright &y& Elsevier]

Ag- and Er-doped glass films have been synthesized with a combined sol-gel and ion-exchange route. The introduction of silver as erbium sensitizer in the film was obtained by ion exchanging Er-doped SiO2-Al2O3-Na2O sol-gel films. The films were subsequently annealed under controlled atmosphere to induce the migration and aggregation of the metal ions. Films showed different Er3+ photoluminescence behaviors depending on silver concentration and aggregation state. The interaction between erbium ions and Ag centers has been investigated and enhancement of the excitation cross section due to the silver sensitizing effect has been demonstrated. The developed synthesis also allowed the realization of erbium-doped channel waveguides by a selective Na-Ag ion-exchange process . [ABSTRACT FROM AUTHOR]

Optically active films in the Y2Ti2O7–Er2Ti2O7 (YETO) system have been deposited using the aerosol–gel process. Photoluminescence properties closely depend on the film crystallization degree. Dilution of erbium ions within a crystalline Y2Ti2O7 matrix (YETO solid solution) allows preventing photoluminescence concentration quenching induced by short range distance interactions. Consequently, heavily doped films with good photoluminescence properties can be obtained. First studies of a YETO-derived microcavity demonstrate the potential of YETO films for integrated optics applications. [Copyright &y& Elsevier]

Optically active Er[SUB2]Ti[SUB2]O[SUB7](ETO) and Y[SUB2-x] (Er[SUBx]Ti[SUB2]O[SUB7] (YETO) films have been successfully deposited using the aerosol-gel process. Several heat-treatment procedures are investigated in the 600-850°C range. ETO and YETO films start to crystallise in the pyrochlore phase at about 750 °C, depending on the heat-treatment time. Crystalline YETO films form a solid solution where the erbium ions are well diluted. Up-conversion emission (UPE) in the visible wavelength range and infrared photoluminescence (PL) at 1.53 μm are investigated. PL spectra are composed of several sharp peaks. Stark splitting of the [SUP4]I[SUB13/2] and [SUB4]I[SUB15/2] erbium levels is analysed. A clear correlation between spectroscopic properties and film microstructure is evidenced. YETO films exhibit strong PL compared to ETO films. PL lifetimes of up to 8.6 ms were measured on YETO films at an erbium concentration of 2 × 10[SUB20] ions/cm[SUP3]. The YETO compound is found to be a suitable material, improving the erbium active properties. [ABSTRACT FROM AUTHOR]

Nd-doped silica glasses have been prepared from a base catalyzed sol–gel solution. The photoluminescence (PL) spectrum and lifetime of the glasses have been studied with respect to their microstructure and chemical composition. It is shown that the glass microstructure depends closely on the solution pH and Nd-doping. A slow decay component (SDC) of the 1060 nm PL, with a lifetime of around 300 μs, and a fast decay component (FDC), with a lifetime of around 0.3 μs, have been identified. The FDC is attributed to Nd3+ ions clusterization inside the silica matrix. It has been shown that the FDC can be almost extinguished and the SDC component substantially increased by Al co-doping. The reasons are twofold: (i) inhibition of the Nd3+ ions clusterization and (ii) intrinsically better PL efficiency of Al co-doped glasses at 1060 nm. Depending on the solution pH, the amount of Nd in the glass can be noticeably increased while preventing a detrimental rare earth clusterization. Thus, a greater glass PL efficiency can be expected. [Copyright &y& Elsevier]

This work deals with the low-temperature preparation of optically active silica-based materials. Tb[sup 3+] -doped silica monolithic gels were elaborated at 40 °C. Tb[sup 3+] –SSA-doped SiO[sub 2] –TiO[sub 2] thin films were deposited by an original sol–gel approach, the aerosol–gel process, and heat-treated at 150 °C. Organic complexation of terbium ions was used to improve the active properties of doped silica gels and thin-film samples. Spectroscopic characterisations are reported for these samples. Photoluminescence increase by a factor two was observed for complexation by sulphosalicylic acid. [ABSTRACT FROM AUTHOR]

This work deals with the low-temperature preparation of optically active silica-based materials. Tb[sup 3+] -doped silica monolithic gels were elaborated at 40 °C. Tb[sup 3+] –SSA-doped SiO[sub 2] –TiO[sub 2] thin films were deposited by an original sol–gel approach, the aerosol–gel process, and heat-treated at 150 °C. Organic complexation of terbium ions was used to improve the active properties of doped silica gels and thin-film samples. Spectroscopic characterisations are reported for these samples. Photoluminescence increase by a factor two was observed for complexation by sulphosalicylic acid. [ABSTRACT FROM AUTHOR]