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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ahj.2005.07.032 Byline: Colin Berry (a), John Norrie (b), Karen Hogg (a), Michael Brett (a), Karen Stevenson (a), John J.V. McMurray (a) Abstract: Anemia is an adverse prognostic marker in heart failure (HF), but its cause and relationships with other comorbidities are uncertain. Author Affiliation: (a) Department of Cardiology, Western Infirmary, Glasgow, Scotland (b) Centre for Healthcare Randomised Trials (ChaRT), University of Aberdeen, Scotland Article History: Received 3 February 2005; Accepted 30 July 2005

Urine recovery in buildings could be an effective way to recover, at the source, nutrients that would otherwise end up in a wastewater treatment plant. However, challenges have emerged with this practice concerning the collection and sanitization of urine in buildings. In fact, current buildings are not designed to receive these systems and integrated solutions able to self-manage the whole process of urine recovery, including the separation, maturation and storage phases, are not available in the market. This work discusses the main technical features of a new approach to collect urine and manage the recovery process at the building level. Several functional aspects, including the dilution ratio of urine in the collected effluent, filling speed of the maturation tanks and storage temperature were studied. Chemical and microbiological analyses carried out over 6 months with real urine have shown that hygienization conditions compatible with gardening and agricultural applications can be achieved. • Innovative toilet capable of separating urine without users having to adapt to. • New setup for controlling the entire recovery process at the building level. • Effluent collection between 5l/day and 30l/day does not affect maturation process. • A treated effluent for fertilization purposes is achieved in less than three months. [ABSTRACT FROM AUTHOR]

Understanding which factors affect the algal bioavailability of dissolved organic nitrogen (DON) compounds in natural surface waters is important for our understanding of nutrient biogeochemistry and water quality management. We used nitrogen uptake kinetics and algal cell yield to characterize the algal bioavailability of 22 dissolved DON compounds that are commonly found in natural surface waters and wastewater treatment plant effluents, including urea, amino acids, amino sugars, nucleotides, pyrimidines, oraganonitriles, polyacrylamide, EDTA, caffeine, phenolic compounds and humic acids. Twelve of these compounds were highly bioavailable, including urea, dissolved free amino acids, bovine serum albumin, DNA, RNA, ATP, AMP, acetonitrile and caffeine. Four compounds had intermediate bioavailability including two humic acids (Elliott Soil and Pahokee Peat), glycylglycine, RNA and uracil. The remaining six compounds were classified as recalcitrant, i.e., EDTA, 2,3-Dinitrophenol, aminobenzoic acid, polyacrylamide and Aldrich humic acid. For many of the compounds tested, the algal cell yield was only 60–80% of expected relative to DON uptake. These results help explain why some DON compounds are more likely to persist in natural systems, and why the DON pool is often recalcitrant in surface waters. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the composition of nitrogen (N) in the effluents of advanced N removal (ANR) wastewater treatment plants (WWTPs). This study also tested two different experimental protocols for determining dissolved N recalcitrance. An analysis of 15 effluent samples from five WWTPs, showed effluent concentrations and especially effluent composition varied greatly from one system to the other, with total nitrogen (TN) ranging between 1.05 and 8.10 mg L −1 . Nitrate (NO 3 − ) accounted for between 38 ± 32% of TN, and ammonium accounted for a further 29 ± 28%. All of these samples were dominated by dissolved inorganic nitrogen (DIN; NO 3 − + NH 4 + ), and uptake experiments indicated the DIN fraction was as expected highly bioavailable. Dissolved organic N (DON) accounted for 20 ± 11% for the total dissolved N in these effluents, and uptake experiments indicated the bioavailability of this fraction varied between 27 ± 26% depending on the WWTP assessed. These results indicate near complete DIN removal should be the primary goal of ANR treatment systems. The comparison of bioavailable nitrogen (BAN) quantification protocols showed that the dissolved nitrogen uptake bioassay approach was clearly a more reliable way to determine BAN concentrations compared to the conventional cell yield protocol. Moreover, because the nitrogen uptake experiment was much more sensitive, this protocol made it easier to detect extrinsic factors (such as biological contamination or toxicity) that could affect the accuracy of these bioassays. Based on these results, we recommend the nitrogen uptake bioassay using filtered and autoclaved samples to quantify BAN concentrations. However, for effluent samples indicating toxicity, algal bioassays will not accurately quantify BAN. [ABSTRACT FROM AUTHOR]

Given the importance of the watershed protection plans, direct determination of phosphorus (P) mineralization rates in advanced wastewater treatment facility effluents is crucial for developing the most protective strategies minimiz eutrophication in receiving surface waters. In this study, algal bioassays were used to determine the uptake rate of dissolved P in effluents from a broad range of advanced nutrient removal technologies (e.g., membrane biological reactor, traditional biological, tertiary membrane, Blue PRO™, etc.). Dissolved P uptake kinetics were fit to a gamma model and three first-order decay models. A traditional one-pool model correlated poorly with the experimental data (i.e., r 2 = 0.73 ± 0.09), whereas two-pool model and three-pool models performed much better (i.e., r 2 > 0.9). These models also provided strong evidence for the existence of recalcitrant P in the effluents from these tertiary facilities. The Gamma model showed the mineralization of organic P followed a reactive continuum and further suggested the partitioning of P loads with different bioavailability levels should be accounted for the future modeling practices. From a modeling perspective, the Gamma model should be considered to be the theoretically best model as it gave the most parsimonious fit to the data using the fewest terms. Our study suggested that the current Total Maximum Daily Load (TMDL) model could be easily modified with the updated mineralization kinetics, which should lead to both ecological and economic benefits. [ABSTRACT FROM AUTHOR]

Several studies have shown Soluble Reactive Phosphorus (SRP) analyses provide a poor index of dissolved phosphorus (P) bioavailability in natural systems. We tested 21 inorganic and organic P containing compounds with series of nutrient uptake and bioavailability bioassay experiments and chemical characterizations. Our results show that in 81% of cases, these compounds did not fit the classic assumption that SRP approximately equals Bioavailable P (BAP). Many organic compounds were classified as non-reactive, but had very rapid uptake kinetics and were nearly entirely bioavailable (e.g., several nucleic acids, ATP, RNA, DNA and phosphatidylcholine). Several inorganic compounds also classified as non-reactive but had high bioavailability (i.e., sodium tripolyphosphate and phosphorus pentoxide). Conversely, apatite was operationally classified as reactive, but had low bioavailability. Due to their tendency to alias as SRP, but recalcitrance and very low bioavailability, humic-(Al/Fe)-phosphorus complexes may play an especially important role in the dissolved phosphorus dynamics of natural systems. [Copyright &y& Elsevier]

Abstract: Aquatic food web models typically treat the constituent trophic levels as static elements interacting with one another and the environment. Dynamic biological stoichiometry has relaxed this assumption and considers evolutionary responses in said elements. The incorporation of organismal response in food web models holds promise for a more realistic portrayal of ecosystem dynamics. Recent advances in aquatic ecology pinpoint the importance of highly unsaturated fatty acids (HUFAs) on food web interactions and ecosystem resilience. In this study, we utilized a HUFA explicit submodel in conjunction with a limiting nutrient–phytoplankton–zooplankton–detritus (NPZD) mathematical system to incorporate elements of the physiology of individual animals into the context of plankton dynamics. Our HUFA-augmented plankton model provided a realistic platform to examine functional properties and physiological strategies that modulate resource procurement in different trophic environments and to effectively link variability at the organismal level with ecosystem-scale patterns. First, we were able to illustrate the implications of the filling-cup hypothesis, in which species’ fitness stems from dynamic HUFA turnover rates in response to bottom-up stresses. We then examined an evolutionary hypothesis of consumer fitness dependence on HUFA quota management strategies, whereby adaptive individuals with low HUFA minimum and optimum requirements gain competitive advantage. Several studies have reported higher HUFA concentrations in consumers than producers, and our results suggest that this pattern could be driven by a combination of conservative turnover and elevated bioconversion rates. Oligotrophic settings showed strong reliance upon exogenous phosphorus subsidies and frequently yielded inverted food web biomass distributions. With the prevalence of eutrophic conditions, consumer growth is primarily controlled by HUFA availability, and the associated biochemical limitation can ultimately result in patterns of algal accumulation. Finally, our study discusses directions to improve the representation of the producer–grazer interactions and thus advance our understanding of the factors that determine the flow of nutrients and energy to the higher trophic levels. [Copyright &y& Elsevier]

Abstract: Because eutrophication is a widespread consequence of wastewater discharges, there is a strong impetus to develop new approaches to remove phosphorus (P) from wastewater treatment plant (WWTP) effluents. We examined the effluents from a pilot plant that is testing various alum based processes for achieving>99% P removal, however, it is not known how these advanced P removal technologies affect the bioavailability of P (BAP). We tested how the percent BAP (%BAP) varied with different P removal levels using an algal growth bioassay methodology. This facility reduced total P concentrations from ≈ 500μgL−1 in the pilot plant influent to 19±4 (±SD)μgL−1 in the final effluent, and our results showed that as the level of P removal increased, the %BAP of the product declined sharply, r 2 =0.98. Prior to alum treatment, the influent had an average %BAP of 79±13%, and after three steps of alum-based removal the %BAP averaged 7±4%. Thus, this alum based P removal process was very effective at sequestering the P forms that most readily stimulate algal growth. Further, our results show the final BAP of the effluent was only ≈ 50% of the “reactive” P concentration. These results have important implications for nutrient management and trading schemes. [Copyright &y& Elsevier]

Abstract: Using total phosphorus concentrations to estimate eutrophication risk is problematic for management purposes, as only some forms of phosphorus are biologically available for phytoplankton growth. This study estimated the bioavailability of particulate phosphorus, in forested, urban, agricultural (i.e. dairy farm) and mixed land cover streams. Sixteen stream sites were sampled during base and storm flow conditions and the following parameters were determined: total suspended solids, total phosphorus, total dissolved phosphorus, particulate phosphorus, percent bioavailable particulate phosphorus (%BAPP), total bioavailable phosphorus and sediment particle size distribution. Algal assays with Pseudokirchneriella subcapitata were used to measure %BAPP. Percent BAPP averaged 17%, 26% and 24% for streams draining catchments with forested, mixed use and agricultural land cover, respectively, and %BAPP did not vary significantly between base and storm flow conditions in these stream types. In contrast, %BAPP averaged 73% in the urban streams during baseflows but declined to an average of only 19% during storms. Particle size distributions did not correlate with %BAPP in these samples. During storm events, particulate phosphorus concentrations increased in all streams by an average of 614% and total phosphorus increased by 200%, whereas total BAP (i.e. total dissolved phosphorus+%BAPP×particulate phosphorus) only increased by 72% because on average only 20% of the particulate phosphorus transported during these events was biologically available. [Copyright &y& Elsevier]

Abstract: Complex environmental models are often criticized as being difficult to analyze and poorly identifiable due to their nonlinearities and/or their large number of parameters relative to data availability. Others consider overparameterized models to be useful, especially for predicting system dynamics beyond the conditions for which the model was calibrated. In this paper, we present a complex eutrophication model that has been developed to simulate plankton dynamics in Lake Washington, USA. Because this model is to be used for testing alternative managerial schemes, the inclusion of multiple elemental cycles (org. C, N, P, Si, O) and multiple functional phytoplankton (diatoms, green algae and cyanobacteria) and zooplankton (copepods and cladocerans) groups was deemed necessary. The model also takes into account recent advances in stoichiometric nutrient recycling theory, and the zooplankton grazing term was reformulated to include algal food quality effects on zooplankton assimilation efficiency. The physical structure of the model is simple and consists of two spatial compartments representing the lake epilimnion and hypolimnion. Global sensitivity analysis showed background light attenuation, the maximum phytoplankton growth rate, the phytoplankton basal metabolic rate, the zooplankton maximum grazing rate and the grazing half saturation constant have the greatest impact on model behavior. Phytoplankton phosphorus stoichiometry (maximum and minimum internal concentrations, maximum uptake rate) interacts with these parameters and determines the plankton dynamics (epilimnetic and hypolimnetic phytoplankton biomass, proportion of cyanobacteria and total zooplankton biomass). Sensitivity analysis of the model forcing functions indicated the importance of both external and internal loading for simulating epilimnetic and hypolimnetic plankton dynamics. These results will be used to calibrate the model, to reproduce present chemical and biological properties of Lake Washington and to test this lake''s potential response to different external nutrient loading scenarios. [Copyright &y& Elsevier]

Abstract: We developed a complex eutrophication model to simulate the current chemical and biological properties of Lake Washington (USA). The model reproduces the key epilimnetic and hypolimnetic temporal patterns of the system and results in a good fit between simulated and observed monthly values. The relative error of model estimates was below 20% for most of the water quality parameters (phytoplankton, phosphate, total phosphorus, total nitrogen, dissolved oxygen). Discrepancies between simulated and observed ammonium levels were mainly due to the explicitly modeled egestion of excess nitrogen during zooplankton feeding. This indicates that the relation between secondary production and nutrient recycling has significant effects on the fractionation of the major elements (C, N and P) and regulates their distribution between the particulate/dissolved and inorganic/organic pools. The model was forced by 1962 nutrient loadings, when the lake received large quantities of treated wastewater treatment effluent, and accurately predicted the phytoplankton community responses (phytoplankton biomass and cyanobacteria dominance) and the nitrogen and phosphorus annual cycles for these conditions. We used Monte Carlo simulations to reproduce the meteorological forcing (air temperature, solar radiation, precipitation and subsequent river inflows) that in large part regulates phytoplankton interannual variability for the last 25 years in the lake. We found three seasonal components (modes of variability). The first component (January, May, November, December) is associated with the conditions that determine the abundance of the herbivorous cladocerans; the second component (June–September) coincides with the summer-stratified period, and the third component (February–April) is associated with the initiation and peak of the spring bloom. Finally, an illustrative application of two scenarios of nutrient loading increase at 25% of the 1962 levels indicated that both phytoplankton and cyanobacteria growth are likely to be stimulated. The three seasonal components still characterize phytoplankton dynamics, but changes in the relationships between summer phytoplankton/cyanobacteria biomass and total phosphorus/phosphate concentrations indicate the likelihood of structural shifts towards relaxation of the present phosphorus-limiting conditions and promotion of cyanobacteria dominance. Integration of the present eutrophication model with a hydrodynamic model with enhanced vertical resolution will allow more realistic predictions. [Copyright &y& Elsevier]

Wind strongly impacts the hydrodynamic and biogeochemical process of large shallow lakes, therefore wind stress also plays an important role in modeling the hydrodynamics and water quality of shallow lakes. In large shallow lakes, it may be necessary to modify the empirical wind-drag coefficient formula derived from ocean surface experiments because lake current velocities may be seriously underestimated in inland waters. To resolve this limitation, we added a wind-drag multiplier (α) to the wind drag formula in a lake hydrodynamic model. We used the Environmental Fluid Dynamics Code (EFDC) to model the hydrodynamics of Upper Klamath Lake (UKL), Oregon. The moment-independent method for global sensitive analysis (GSA) based on sampling of input parameters was utilized. We found that the original model underestimated lake current velocities when compared to field observations, so we developed a modified model with a wind-drag multiplier. This model was calibrated to observed data from June 21–September 12, 2005, and verified with data from May 24–September 25, 2006. The results showed the calibrated modified model resolved the underestimation problem, e.g., at three sites in UKL the water velocity increased by 59–85%, and the relative error for the model decreased by 15–32%. Sensitivity analysis showed the modeled current velocities were more sensitive to the α coefficient than to the bottom roughness height z 0 and the coefficients in the original wind-drag formula. We believe the wind-drag multiplier affects wave propagation in the model and reconciles the mismatch between large shallow lake and open ocean conditions. Our results show that a relatively simple modification can alleviate the fundamental mismatch between modeling the hydrodynamics of the open ocean and large shallow lakes. • Underestimation of current velocities was corrected by adding a wind drag multiplier. • The water current velocities were the most sensitive to the wind drag multiplier according to a global sensitivity analysis. • The model sensitivity was not affected by location under spatially uniform wind forcing. • The effect of the wind drag multiplier on model performance might be related to wave-inducing forcing. [ABSTRACT FROM AUTHOR]

This study examined the physical, chemical and biological characteristics of the phosphorus (P) in the effluents from a paper processing facility before and after an alum based P removal process. The alum based treatment process reduced effluent total P concentrations from an average of 230 ± 103 (±1 SD) μg L−1 to an average of 36 ± 10 μg L−1. Ultra-filtration showed the treatment process shifted the P in these effluents from being 75 ± 9% particulate pre-removal to being 52 ± 0% dissolved and 27 ± 1% colloidal after the Trident P removal process. The alum removal process also reduced the fraction of reactive P in the dissolved and colloidal pools from 55% to 14%, respectively. Algal phosphorus bioavailability (BAP) bioassays showed the BAP of these effluents averaged 12 ± 9% of total P. Algal dissolved P uptake experiments indicated ≈ 30% of the dissolved P was converted to particulate P (which usually indicates algal uptake) during 21-day bioassays. However, treatments without algae indicated >80% of the apparent algal uptake may have been due to colloidal P forming flocs via physical-chemical processes. These analyses indicate the phosphorus contained in this paper processing facility's effluents had much lower bioavailability than the P in typical municipal wastewater treatment plant effluents. Unlabelled Image • Alum based technology was effective in treating paper processing facility effluent. • P in the effluent from paper processing facility had very low bioavailability. • Most of the P in the paper mill effluents tested was humic bound. • P uptake in bioassay experiment was mainly due to physical-chemical processes. [ABSTRACT FROM AUTHOR]

Green roofs are increasingly being used to improve the energy balance and stormwater management of buildings. This work examines the thermal behaviour, water drainage and vegetation growth of two green roof systems: a conventional system containing extruded polystyrene and polyethylene, and an alternative cork-based system. In the new system, an eco-friendly expanded cork layer is used to provide thermal resistance and water storage capacity in a more sustainable way, as cork is a natural material. This material can also be used as an uncoated finishing layer for architectural purposes. The main goal of this work was to see if the new system is reliable in real environmental conditions and to compare its behaviour to that of the conventional system for a full year. This work presents the results of a fully functioning prototype built in Portugal with a technical substrate 10 cm thick and planted with a variety of vegetation. The reference and proposed systems were installed side by side and monitored under spring, summer, autumn and winter conditions. The thermal insulation and the water drainage and storage capacity provided by the cork-based green roof were found to be similar to those of the reference solution, with the expanded cork layer showing a more marked temperature delay and a more effective management of rainfall events under dry conditions. Additionally, it was found that the growth and health of plants in the cork-based green roof were comparable to those of the reference solution, indicating the good performance of the cork system. • An innovative cork-based green roof system was compared with a conventional solution. • Thermal, drainage and vegetation behaviour were assessed under real conditions. • More pronounced temperature delays were exhibited by the cork-based system. • The cork-based system was more effective at managing the drainage of the first rainfall event. • Vegetation development was similar for the two green roofs compared here. [ABSTRACT FROM AUTHOR]

Abstract: Many efforts have been made to incorporate our improved understanding of zooplankton physiology and behaviour into mathematical models. The increased complexity, however, has been a major impediment in integrating these advances into management-oriented models and thus bridging the gap between theoretical and applied ecology. In this study, we enhance an existing eutrophication model with a zooplankton somatic growth submodel that simulates the interplay among nitrogen, phosphorus, and highly unsaturated fatty acids (HUFAs) through the grazers’ digestive tracks. We calibrate the newly incorporated parameters (and associated processes) against observed data from the mesotrophic Lake Washington. We extrapolate the model to different trophic environments and tease out the underlying drivers of zooplankton growth. Our analysis suggests that both stoichiometric and HUFA based somatic growth limitations can modulate the zooplankton biomass in mesotrophic environments. Food abundance and mineral P limitation are critical factors of zooplankton growth under oligotrophic conditions, while HUFA availability is the main driving force of plankton dynamics in eutrophic states. Our zooplankton submodel downplays pre-gut regulation in favour of post-gut metabolic processing, which appears to shift the bulk of the non-limiting nutrient recycling from particulate to dissolved form. The homeostatic maintenance of somatic quotas and the dynamic nutrient recycling could also be an important mechanism for shedding light on the controversial hypothesis that the enrichment of natural ecosystems is a destabilizing factor of food web dynamics. [Copyright &y& Elsevier]

Abstract: The porous nature of high surface area and large aspect ratio nanorods arrays make them strong candidates for a range of applications from catalyst supports to energy scavenging devices. The glancing angle deposition (GLAD) technique is a straightforward and flexible method for ensuring control of morphology and porosity in nanorod arrays. Quantifying the porous nature of nanostructured columnar arrays, fabricated using the GLAD technique, is critical for understanding and optimizing the performance of devices fabricated using this method. The mesoporosity and pore volume of these GLAD nanorod arrays have thus been characterized using gas adsorption (krypton adsorption at 87.3K) and scanning electron microscopy (SEM) image analysis techniques. To characterize the obliquely deposited amorphous titanium dioxide (TiO2) and silicon dioxide (SiO2) samples, top-down SEM images of the films were also analyzed which allowed us to determine the mean distance between columns. SEM image analysis permitted for estimation of inter-column porosity of films deposited at angles from 65° to 85°, while krypton analysis allowed for the identification of mesoporosity in films from 45° to 85°. Our results provide a comprehensive characterization of GLAD film porosity which will be vital for the design of devices for a diverse set of applications from photonics to sensing to microfluidics. [Copyright &y& Elsevier]

Abstract: Glancing angle deposition (GLAD) was used to deposit controlled-porosity TiO2 thin films of varying pore size and shape. Hybrid materials were fabricated by infiltrating the TiO2 films with poly(3-hexylthiophene) (P3HT) using a spin casting process, which were either employed as-cast or subjected to thermal processing. Photovoltaic devices fabricated using these hybrid materials were characterized as a function of TiO2 pore size and shape, and thermal processing. It was found that the optimum pore size was dependent on the thermal history of the sample. When as-cast hybrid materials were employed conversion efficiencies decreased with increasing pore size. When hybrid materials annealed above the melting point of P3HT were employed the trend was reversed, with conversion efficiency increasing with increasing pore size. Trends in conversion efficiency were found to correlate with P3HT crystallinity, demonstrating that optimum pore sizes for hybrid devices of this type are dependent on sample processing. [ABSTRACT FROM AUTHOR]

Temporal variability in lake phytoplankton is controlled largely by a complex interplay between hydrodynamic and chemical factors, and food web interactions. We explored mechanisms underlying phytoplankton interannual variability in Lake Washington (USA), using a 25-yr time series of water quality data (1975–1999). Time-series analysis and PCA were used to decompose chlorophyll data into modes of variability. We found that phytoplankton dynamics in Lake Washington were characterized by four seasonal modes, each of which was associated with different ecological processes. The first mode coincided with the period when the system was light limited (January–March) and phytoplankton patterns were driven by the amount of available solar radiation. The second mode (April–June) coincided with the peak of the spring bloom and the subsequent decline of phytoplankton biomass, and was largely controlled by total phosphorus levels and grazing pressure from cladoceran zooplankton. Evidence of co-dependence and tight relationship between phytoplankton and cladoceran dynamics were also found from July to October when a large portion of the phosphorus supply in the mixed layer was provided by zooplankton excretion. The fourth mode (November–December) was associated with the transition to thermal and chemical homogeneity and the winter phytoplankton minima (2–2.5μg/l). Finally, we examined the effects of meteorological forcing and large-scale oceanic climate fluctuations (ENSO and PDO) on phytoplankton dynamics and assessed the significance of their role on the interannual variability in the lake. [Copyright &y& Elsevier]

Lake size influences various hydrological parameters, such as water retention time, circulation patterns and thermal stratification that can consequently affect the plankton community composition, benthic–pelagic coupling and the function of aquatic food webs. Although the socio-economical (particularly commercial fisheries) and ecological importance of large lakes has been widely acknowledged, little is known about the availability and trophic transfer of polyunsaturated fatty (PUFA) in large lakes. The objective of this study was to investigate trophic trajectories of PUFA in the pelagic food web (seston, zooplankton, and planktivorous fish) of six large boreal lakes in the Finnish Lake District. Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and α-linolenic acid (ALA) were the most abundant PUFA in pelagic organisms, particularly in the zooplanktivorous fish. Our results show that PUFA from the n-3 family (PUFAn-3), often associated with marine food webs, are also abundant in large lakes. The proportion of DHA increased from ~ 4 ± 3% in seston to ~ 32 ± 6% in vendace ( Coregonus albula ) and smelt ( Osmerus eperlanus ), whereas ALA showed the opposite trophic transfer pattern with the highest values observed in seston (~ 11 ± 2%) and the lowest in the opossum shrimp ( Mysis relicta ) and fish (~ 2 ± 1%). The dominance of diatoms and cryptophytes at the base of the food web in the study lakes accounted for the high amount of PUFAn-3 in the planktonic consumers. Furthermore, the abundance of copepods in the large lakes explains the effective transfer of DHA to planktivorous fish. The plankton community composition in these lakes supports a fishery resource (vendace) that is very high nutritional quality (in terms of EPA and DHA contents) to humans. [ABSTRACT FROM AUTHOR]

Ni nanopillar structures were fabricated on glassy carbon electrodes (Ni GLAD /GC) using glancing angle deposition (GLAD). Thin, conformal layers of Pt were deposited by a rotating substrate, self-limiting, high current density galvanostatic deposition to form Ni GLAD {Pt}/GC deposits. The Pt loading in the Ni GLAD {Pt}/GC deposits was systematically varied by interrupting the deposition at various coverages, and the series of the Ni GLAD {Pt}/GC deposits were evaluated as catalysts for the oxygen reduction reaction (ORR) in O 2 saturated, 0.1 M HClO 4 at room temperature. The optimum amount of Pt (initial wt. ratio ∼ Pt 0.22 Ni 0.78 ) was deposited over 800 to 1500 seconds. These deposits, after dealloying, were about 30 times more active by mass and by surface area than a {Pt}/GC electrode prepared by deposition of Pt onto GC under the same conditions. [ABSTRACT FROM AUTHOR]

Glancing Angle Deposition (GLAD) was used to prepare 500 nm long Ni nanopillars directly on glassy carbon disc electrodes (Ni GLAD /GC). Ni GLAD {Pt}/GC core-layer nanopillars were prepared by depositing Pt on the Ni GLAD substrate via a novel rotating disc electrode galvanostatic deposition, where a stationary blackened Pt counter electrode served as the Pt source. Scanning electron microscopy, cyclic voltammetry, and inductively-coupled mass spectrometry were employed to characterize the deposits. Results indicated that the Pt was deposited in a conformal manner on the Ni GLAD giving a loading of 11.6 μg. The Ni GLAD {Pt}/GC electrode was ca. three fold more active than a {Pt}/GC (made with the same deposition in the absence of Ni) towards the oxygen reduction reaction (ORR) in 1.0 M KOH. As well, long term potentiostatic ORR studies showed the Ni GLAD {Pt}/GC deposit was more durable than the {Pt}/GC, with the former completely retaining its initial performance after 5000 s polarization at 0.85 V vs. RHE, while {Pt}/GC lost 38% of its activity. Subsequent control experiments in the absence of O 2 showed that such decay was not due to loss of Pt over the prolonged ORR. [ABSTRACT FROM AUTHOR]

Highlights: [•] Study of anisotropic SiO2, Al2O3, TiO2, and ZrO2 GLAD UTLC stationary phases. [•] Chromatographic merits evaluated using carotenoid and food dye mixtures. [•] Separation performance depended on material, oxidation heat treatments, and UV irradiation. [•] First successful GLAD UTLC–ESI-MS recording of dyes on inorganic ultrathin films. [•] New GLAD UTLC layers may separate samples better than traditional miniaturized sorbents. [Copyright &y& Elsevier]

Abstract: Iron pyrite is a promising material for photovoltaic power production due to low material extraction and processing costs and high optical absorption. Reliable production of photovoltaic grade iron pyrite thin films has, however, been challenging. One potential fabrication route is the direct conversion of iron-to-iron pyrite by sulfur annealing (sulfurization). Bulk iron thin films are used typically but they can suffer from cracking or delamination. Herein we report the sulfurization of porous, columnar Fe films deposited with Glancing Angle Deposition (GLAD), which allows us to control the inter-column spacing (void-fraction) of the precursor film. We show that the morphology and microstructure of the iron pyrite films are strongly affected by the void-fraction. By precisely tuning the void-fraction of the precursor film at 82° oblique angle incidence deposition we can produce iron pyrite films with increased crystallite sizes >100nm with a uniform, crack-free, facetted granular microstructure. Large crystallites may reduce carrier recombination at grain boundaries, which is attractive for photovoltaic devices. Further increasing the void-fraction produces a columnar iron pyrite structure. We also report composition, electrical and optical characterization including a 27ps lifetime of photocarriers measured with ultrafast optical-pump/THz-probe. Structured, porous precursors offer an alternate route to control microstructure and film stress during fabrication of iron pyrite thin films. [Copyright &y& Elsevier]

Abstract: Nb-doped TiO2 (TNO) has been widely explored as an alternative transparent conductor. TNO thin films have been fabricated by various deposition methods, and here we demonstrate fabrication by evaporation of sol–gel synthesized TNO source material. A range of Nb x Ti1− x O2 (x =0, 0.03, 0.06, 0.12, 0.24) compositions were synthesized, pressed into pellets, and deposited as thin films via electron beam evaporation. The thin films were characterized for composition by energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy and for crystallinity by X-ray diffraction for the different Nb contents explored. Transparency, conductivity, and Haacke transparent conductor figure of merit values are reported for the evaporated TNO films as a function of Nb content, substrate heating temperature, and post deposition annealing conditions. Glancing angle deposition (GLAD) is used to demonstrate nanostructuring of evaporated TNO based on physical shadowing. Nanostructured GLAD TNO films of increased morphological complexity can be produced using this method, and could lead to unique transparent conductor device architectures. [Copyright &y& Elsevier]

Abstract: Metal oxides such as niobium oxides have been demonstrated as alternative support materials for Pt and non-precious metal catalysts in fuel cells. High surface area and columnar niobium oxide catalyst support structures were produced by the glancing angle deposition (GLAD) technique on 5mm diameter glassy carbon disks. The columnar structures have lengths of about 500nm, diameters of 50nm and an areal density of about 109 cm−2. Annealing under different gas mixtures (Ar/H2) led to the formation of various oxides (Nb2O5, NbO2, or NbO+NbO2). Pt catalyst, with a loading of 0.1mgPt cm−2, was deposited onto these structures by magnetron sputter deposition. Rotating disk electrode characterization of the samples, performed in 0.1M HClO4 electrolyte at room temperature, revealed surface enhancement factors of up to 11 and oxygen reduction specific activities of ≥1mAcm−2 Pt at 0.9V (vs. RHE). The impact of annealing on Nb-O phase formation, conductivity, oxygen reduction activity and stability are discussed. [Copyright &y& Elsevier]

The paradigm that mangrove carbon supports secondary production in mangrove and adjacent habitats has been debated in recent years. Fatty acids (FA) are one of the classic biomarkers that have been frequently applied to track mangrove carbon pathways and assess trophic relationships. However, most previous studies did not evaluate the validity, potential and limitations of FA as biomarkers. The function and metabolism of long-chain polyunsaturated FA (LC-PUFA) in mangrove fauna have been largely ignored, and overlapping single FA biomarkers were widely used to infer dietary contributions from different sources. This review aims to systematically analyze and assess the application of FA biomarkers to dietary analyses in mangrove ecosystems, with a focus on basal food sources and their consumers. Our results show that basal food sources have distinctive FA profiles, with leaves and litter rich in alpha-linolenic acids (ALA, 18:3n-3), microphytobenthos rich in eicosapentaenoic acids (EPA, 20:5n-3) and suspended particulate organic matter (SPOM), or phytoplankton rich in docosahexaenoic acids (DHA, 22:6n-3). Most consumers contain high contents of LC-PUFA, particularly DHA and EPA, but very low levels of long-chain saturated FA (e.g., 22:0, 24:0, 26:0, 28:0), a biomarker of mangrove leaf litter. Bacterial FA biomarkers are present in all consumers. Four possible carbon pathways are identified and examined, i.e., benthic feeding on mangrove leaves and litter, benthic feeding on microphytobenthos, pelagic feeding on SPOM, and benthic and pelagic feeding on bacteria. Each pathway plays a different nutritional role for consumers, together providing a diversity of carbon sources. We recommend that in future (a) a wide range of basal diet sources should be sampled rather than just "visible" sources; (b) the unique FA characteristics of each diet source and consumer should be recognized with a focus on overall FA profiles and the application of multivariate statistics; (c) controlled feeding trials should be considered for keystone or functionally important consumers before selecting certain FA biomarkers to infer animal diets, and; (d) compound-specific stable isotope analysis should be applied to provide more insights into trophic relationships as well as the FA metabolic pathways in consumers. Unlabelled Image • First assessment of fatty acids (FA) as biomarkers in mangrove ecosystems was done. • Basal food sources show distinctive FA profiles. • Consumers contain high amounts of essential FA and very low levels of long-chain saturated FA. • Most consumers exhibit a mixed feeding strategy, rather than simply selecting diets rich in essential FA. • Carbon pathway plays a different nutritional role for consumers. [ABSTRACT FROM AUTHOR]