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RATIONALE: Thin, nanoporous films fabricated using Glancing Angle Deposition (GLAD) technology are demonstrated for solid matrix laser desorption/ionization mass spectrometry (SMALDI-MS). GLAD allows facile engineering of nanoporosity, film thickness, post alignment, and material composition, as demonstrated here by the fabrication of Co-GLAD and Si-GLAD films for SMALDI, and by exploration of the SMALDI performance as a function of thickness, post density, and angle of the post relative to surface normal. METHODS: GLAD films were prepared by electron beam evaporation onto silicon substrates, using steep angles of incidence for the vacuum deposition, with computer controlled substrate rotation. LDI from the GLAD films was evaluated using an MDS-Sciex time-of-flight (TOF) MALDI mass spectrometer. RESULTS: Co-GLAD films give a limit of quantitation of 6 fmol for complex carbohydrate derivatives, and slanted-post Si-GLAD films show up to three times higher sensitivity than vertical post structures. Reproducibility of both Si and Co films is much higher than conventional MALDI methods for m/z below at least 2100 Da. Both reproducibility and detection limits are comparable to or better than other nano-structured materials. Co-GLAD films are significantly better in performance than Co powders or Co thin films on silicon substrates previously evaluated. CONCLUSIONS: The flexibility of GLAD for thin film fabrication of LDI materials is demonstrated by the range of nanoporous materials that can be grown, and the fine control over structural conformation, thickness and porosity. [ABSTRACT FROM AUTHOR]

Spawning migrations of Pacific salmon ( Oncorhynchus spp.) to coastal watersheds provide a rich resource subsidy to freshwater consumers. However, variation in thermal regimes and spawning activity across the landscape constrain the ability of poikilothermic consumers to assimilate eggs and carcasses. We investigated how sockeye salmon ( Oncorhynchus nerka) spawning density and stream temperature affect the growth, body condition, and fatty acid composition of juvenile coho salmon ( Oncorhynchus kisutch), a known egg predator, in seven tributaries of the Wood River in Southwest Alaska. We compared mean body size of juvenile coho salmon in late summer among 3-7 years per stream and found that the largest mean size occurred in warm streams in which sockeye salmon spawned, although overall subsidy magnitude (spawner density) had no effect on consumer body size. Individuals that consumed more salmon eggs (estimated from δ15N) were larger and had altered fatty acid composition but did not have higher relative body condition. These results indicate that effects of marine subsidies on freshwater consumers depend both on local habitat conditions and on individual variation in energy allocation. [ABSTRACT FROM AUTHOR]

The proposed interoceanic canal will connect the Caribbean Sea with the Pacific Ocean, traversing Lake Nicaragua, the major freshwater reservoir in Central America. If completed, the canal would be the largest infrastructure-related excavation project on Earth. In November 2015, the Nicaraguan government approved an environmental and social impact assessment (ESIA) for the canal. A group of international experts participated in a workshop organized by the Academy of Sciences of Nicaragua to review this ESIA. The group concluded that the ESIA does not meet international standards; essential information is lacking regarding the potential impacts on the lake, freshwater and marine environments, and biodiversity. The ESIA presents an inadequate assessment of natural hazards and socioeconomic disruptions. The panel recommends that work on the canal project be suspended until an appropriate ESIA is completed. The project should be resumed only if it is demonstrated to be economically feasible, environmentally acceptable, and socially beneficial. [ABSTRACT FROM AUTHOR]

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]

Ir–Ni oxide nanoparticles were simply prepared by stirring IrCl 3 and NiCl 2 precursors in aqueous base under air. The activities of a series of IrNi y O x nanoparticles with different Ir-to-Ni ratios were measured toward water oxidation in 0.1 M H 2 SO 4 . The Ir-to-Ni ratio was 1:0.125 in the most active catalyst (mass normalized > 140 A g − 1 Ir, electrochemically active surface area normalized > 203 A mmol − 1 Ir). The stabilized potential for the galvanostatic oxidation (1 mA cm − 2 geometric ) was as low as 1.51 V RHE , corresponding to 0.28 V in overpotential. [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]

Stable isotope mixing models in aquatic ecology require δ13C values for food web end members such as phytoplankton and bacteria, however it is rarely possible to measure these directly. Hence there is a critical need for improved methods for estimating the δ13C ratios of phytoplankton, bacteria and terrestrial detritus from within mixed seston. We determined the δ13C values of lipids, phospholipids and biomarker fatty acids and used these to calculate isotopic differences compared to the whole-cell δ13C values for eight phytoplankton classes, five bacterial taxa, and three types of terrestrial organic matter (two trees and one grass). The lipid content was higher amongst the phytoplankton (9.5±4.0%) than bacteria (7.3±0.8%) or terrestrial matter (3.9±1.7%). Our measurements revealed that the δ13C values of lipids followed phylogenetic classification among phytoplankton (78.2% of variance was explained by class), bacteria and terrestrial matter, and there was a strong correlation between the δ13C values of total lipids, phospholipids and individual fatty acids. Amongst the phytoplankton, the isotopic difference between biomarker fatty acids and bulk biomass averaged -10.7±1.1‰ for Chlorophyceae and Cyanophyceae, and -6.1±1.7‰ for Cryptophyceae, Chrysophyceae and Diatomophyceae. For heterotrophic bacteria and for type I and type II methane-oxidizing bacteria our results showed a -1.3±1.3‰, -8.0±4.4‰, and -3.4±1.4‰ δ13C difference, respectively, between biomarker fatty acids and bulk biomass. For terrestrial matter the isotopic difference averaged -6.6±1.2‰. Based on these results, the δ13C values of total lipids and biomarker fatty acids can be used to determine the δ13C values of bulk phytoplankton, bacteria or terrestrial matter with ± 1.4‰ uncertainty (i.e., the pooled SD of the isotopic difference for all samples). We conclude that when compound-specific stable isotope analyses become more widely available, the determination of δ13C values for selected biomarker fatty acids coupled with established isotopic differences, offers a promising way to determine taxa-specific bulk δ13C values for the phytoplankton, bacteria, and terrestrial detritus embedded within mixed seston. [ABSTRACT FROM AUTHOR]

The article discusses the concerns of environmental scientists on the awarding of a concession to infrastructure development firm Hong Kong Nicaragua Development Corp. (HKND) in June 2013 for the construction of an interoceanic canal across Nicaragua and other projects such as oil pipeline and international airports. The author finds that the government did not hold a bidding process for the construction projects and conduct assessments on their socio-economic and environmental impact.

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]

The zooplankton is a key link in the transfer of energy from primary producers up through aquatic food webs. Previous efforts to quantify the importance of basal resources to aquatic consumers have used stable isotopes ( SI) and simple ternary models, including only 'bulk' phytoplankton, bacteria or terrestrial particulate organic matter (t- POM)., We used a novel Bayesian mixing model based on fatty acids ( FA) to quantify the dietary assimilation of seven basal resources, including five phytoplankton groups, pelagic bacteria and t- POM, to Cladocera in large boreal lakes in Finland. To account for trophic enrichment of FA from the diet to consumers, we parameterised the model with a resource library, from many feeding trials, consisting of Daphnia magna fed 22 diverse basal taxa., The results of the feeding trials show that the distinctive FA profiles of algal groups are transferred to consumers. Moreover, the large number of FA variables ( n = 22) used in the model avoids the limitations of underdetermined mixing problems, common to SI modelling, in cases when the number of resources outnumbers the tracer variables., We show that cladocerans were generally supported by phytoplankton (86-94%), with little use of t- POM (1-9%) and bacteria (1-3%). Cladocerans used primarily high-quality phytoplankton (cryptophytes, diatoms and dinoflagellates) in both summer (51 ± 22%) and autumn (79 ± 12%), and the relative importance of medium-quality resources (cyanobacteria, chlorophytes and chrysophytes) declined from 37 ± 23% in the summer to 8 ± 2% in the autumn., High-quality resources, rich in essential biochemical compounds, are critical in fuelling food webs in large lakes, even those with high concentrations of allochthonous organic matter. [ABSTRACT FROM AUTHOR]

Branchgrowth is directed along two, three, or four in-plane directionsin vertically aligned nanowire arrays using vapor–liquid–solidglancing angle deposition (VLS-GLAD) flux engineering. In this work,a dynamically controlled collimated vapor flux guides branch placementduring the self-catalyzed epitaxial growth of branched indium tinoxide nanowire arrays. The flux is positioned to grow branches onselect nanowire facets, enabling fabrication of aligned nanotree arrayswith L-, T-, or X-branching. In addition, a flux motion algorithmis designed to selectively elongate branches along one in-plane axis.Nanotrees are found to be aligned across large areas by X-ray diffractionpole figure analysis and through branch length and orientation measurementscollected over 140 μm2from scanning electron microscopyimages for each array. The pathway to guided assembly of nanowirearchitectures with controlled interconnectivity in three-dimensionsusing VLS-GLAD is discussed. [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]

Ultrathin-layer chromatography (UTLC) potentially offers faster analysis, reduced solvent and sample volumes, and lower costs. One novel technique for producing UTLC plates has been glancing angle deposition (GLAD), a physical vapor deposition technique capable of aligning macropores to produce interesting separation properties. To date, however, GLAD-UTLC plates have been restricted to model dye systems, rather than realistic analytes. This study demonstrates the transfer of high-performance thin-layer chromatography (HPTLC) sugar analysis methods to GLAD-UTLC plates using the office chromatography framework. A consumer inkjet printer was used to apply very sharp low volume (3-30 nL) bands of water-soluble analytes (lactose, sucrose, and fructose). Analytic performance measurements extrapolated the limits of detection to be 3-5 ng/zone, which was experimentally proven down to 60-70 ng/band, depending on the sugar. This qualitative analysis of sugars in a commercially available chocolate sample is the first reported application of GLAD-UTLC to food samples. The potential utility of GLAD-UTLC is further exemplified by successful coupling with electrospray ionization mass spectrometry for the first time to characterize underivatized sugars. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new technique is developed to fabricate biomimetic antireflection coatings (ARCs). This technique combines a bottom-up fabrication approach (glancing angle deposition, or GLAD) with a top-down engineering process (ion milling). The GLAD technique is first utilized to produce nanopillar arrays (NPAs) with broadened structures, which are subsequently transformed into biomimetic tapered geometries by means of post-deposition ion milling. This structure transformation, due to milling-induced mass redistribution, remarkably decreases reflection over a wide wavelength range (300–1700 nm) and field of view (angle of incidence < 60° with respect to the substrate normal). The milling-induced antireflection enhancement has been demonstrated in the NPAs made of Si, SiOx and TiO2, illustrating that this integrated technique is readily adapted to a wide variety of materials. Good agreement between simulation and experiment indicates that the enhanced antireflection performance is ascribed to a smoother refractive index transition from the substrate to the air, which improves the impedance match and reduces reflection losses. Additionally, ion bombardment tends to alter the stoichiometry and diminish the crystallographic structure of the NPA materials. The broadband and quasi-omnidirectional antireflection observed establishes the strong competitiveness of this technique with the methods previously reported. [ABSTRACT FROM AUTHOR]

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]

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]

Combining vapour-liquid-solid growth with glancing angle deposition (VLS-GLAD) facilitates fabrication of branched nanowires not possible with either technique alone. Indium tin oxide (ITO) nanostructures grown by VLS-GLAD produce extremely porous nanotree structures, where periodic branch diameter oscillations are sometimes observed. We explain this rippled branch growth with a simple model linking the physics governing branch growth to the process variables controlled in VLS-GLAD. The model is verified by inducing specific, aperiodic ripples onto growing ITO branches through macroscopic vapour flux control and manipulation of local shadowing. [ABSTRACT FROM AUTHOR]

Primary productivity by plants and algae is the fundamental source of energy in virtually all food webs. Furthermore, photosynthetic organisms are the sole source for ω-3 and ω-6 essential fatty acids (EFA) to upper trophic levels. Because animals cannot synthesize EFA, these molecules may be useful as trophic markers for tracking sources of primary production through food webs if different primary producer groups have different EFA signatures. We tested the hypothesis that different marine macrophyte groups have distinct fatty acid (FA) signatures by conducting a phylogenetic survey of 40 marine macrophytes (seaweeds and seagrasses) representing 36 families, 21 orders, and four phyla in the San Juan Archipelago, WA, USA. We used multivariate statistics to show that FA composition differed significantly ( P < 0.001) among phyla, orders, and families using 44 FA and a subset of seven EFA ( P < 0.001). A second analysis of published EFA data of 123 additional macrophytes confirmed that this pattern was robust on a global scale ( P < 0.001). This phylogenetic differentiation of macrophyte taxa shows a clear relationship between macrophyte phylogeny and FA content and strongly suggests that FA signature analyses can offer a viable approach to clarifying fundamental questions about the contribution of different basal resources to food webs. Moreover, these results imply that taxa with commercially valuable EFA signatures will likely share such characteristics with other closely related taxa that have not yet been evaluated for FA content. [ABSTRACT FROM AUTHOR]

We tailored nanostructured morphology and crystal textureof ironnanocolumns by engineering the inclination and azimuthal directionsof the collimated flux characteristic of glancing angle deposition(GLAD). Under continuous substrate rotation, the flux is azimuthallyisotropic within one rotation. With large substrate rotation speeds,we can deposit vertical nanocolumns with a faceted, tetrahedral apex,BCC crystal structure and ⟨111⟩ fiber texture. Designingthe flux to have an azimuthal 3-fold symmetry, which reflects thesymmetry of the tetrahedral apex, allows us to induce both an in-planeand out-of-plane texture (biaxial texture) by evolutionary selection.In-plane crystal orientation is accompanied by a preferential azimuthalnanocolumn orientation, where the sides of tetrahedral apex are directedtoward the flux direction. This work demonstrates the flux engineeringtechnique, which can orient in-plane crystal texture and morphologyof crystalline nanocolumns on amorphous substrates. This control isa useful addition to vapor–solid, physical self-assembly withthe potential to improve the performance of porous thin film architecturesas biaxial buffer layers, and in a variety of device applicationssuch as photovoltaics and energy storage. [ABSTRACT FROM AUTHOR]

The E3 ubiquitin ligase MDM2 functions as a crucial negative regulator of the p53 tumor suppressor protein by antagonizing p53 transactivation activity and targeting p53 for degradation. Cellular stress activates p53 by alleviating MDM2-mediated functional inhibition, even though the molecular mechanisms of stress-induced p53 activation still remain poorly understood. Two opposing models have been proposed to describe the functional and structural role in p53 activation of Ser17 phosphorylation in the N-terminal "lid" (residues 1-24) of MDM2. Using the native chemical ligation technique, we synthesized the p53-binding domain (1-109)MDM2 and its Ser17-phosphorylated analogue (1-109)MDM2 pS17 as well as (1-109)MDM2 S17D and (25-109)MDM2, and comparatively characterized their interactions with a panel of p53-derived peptide ligands using surface plasmon resonance, fluorescence polarization, and NMR and CD spectroscopic techniques. We found that the lid is partially structured in apo-MDM2 and occludes p53 peptide binding in a ligand size-dependent manner. Binding of (1-109)MDM2 by the (15-29)p53 peptide fully displaces the lid and renders it completely disordered in the peptide-protein complex. Importantly, neither Ser17 phosphorylation nor the phospho-mimetic mutation S17D has any functional impact on p53 peptide binding to MDM2. Although Ser17 phosphorylation or its mutation to Asp contributes marginally to the stability of the lid conformation in apo-MDM2, neither modification stabilizes apo-MDM2 globally or the displaced lid locally. Our findings demonstrate that Ser17 phosphorylation is functionally neutral with respect to p53 binding, suggesting that MDM2 phosphorylation at a single site is unlikely to play a dominant role in stress-induced p53 activation. [ABSTRACT FROM AUTHOR]

Nanoporous films of indium tin oxide (ITO), with thicknesses ranging from 250 nm to 2 μm, were prepared by Glancing Angle Deposition (GLAD) and used as highly sensitive transparent 3D-electrodes for quantitatively interrogating, by time-resolved spectroelectrochemistry, the reactivity of microperoxidase-11 (MP-11) adsorbed within such films. The capacitive current densities of these 3D-electrodes as well as the amount of adsorbed MP-11 were shown to be linearly correlated to the GLAD ITO film thickness, indicating a homogeneous distribution of MP-11 across the film as well as homogeneous film porosity. Under saturating adsorption conditions, MP-11 film concentration as high as 60 mM was reached. This is equivalent to a stack of 110 monolayers of MP-11 per micrometer film thickness. This high MP-11 film loading combined with the excellent ITO film conductivity has allowed the simultaneous characterization of the heterogeneous one-electron transfer dynamics of the MP-11 FeIII/FeII redox couple by cyclic voltammetry and cyclic voltabsorptometry, up to a scan rate of few volts per second with a satisfactory single-scan signal-to-noise ratio. The potency of the method to unravel complex redox coupled chemical reactions was also demonstrated with the catalytic reduction of oxygen by MP-11. In the presence of O2, cross-correlation of electrochemical and spectroscopic data has allowed us to determine the key kinetics and thermodynamics parameters of the redox catalysis that otherwise could not be easily extracted using conventional protein film voltammetry. On the basis of numerical simulations of cyclic voltammograms and voltabsorptograms and within the framework of different plausible catalytic reaction schemes including appropriate approximations, it was shown possible to discriminate between different possible catalytic pathways and to identify the relevant catalytic cycle. In addition, from the best fits of simulations to the experimental voltammograms and voltabsorptograms, the partition coefficient of O2 for the ITO film as well as the values of two kinetic rate constants could be extracted. It was finally concluded that the catalytic reduction of O2 by MP-11 adsorbed within nanoporous ITO films occurs via a 2-electron mechanism with the formation of an intermediate FeIII-OOH adduct characterized by a decay rate of 11 s-1. The spectroelectroanalytical strategy presented here opens new opportunities for characterizing complex redox-coupled chemical reactions not only with redox proteins, but also with redox biomimetic systems and catalysts. It might also be of great interest for the development and optimization of new spectroelectrochemical sensors and biosensors, or eventually new photoelectrocatalytic systems or biofuel cells. [ABSTRACT FROM AUTHOR]

Lethal control, which has been used to reduce local abundances of animals in conflict with humans or with endangered species, may not achieve management goals if animal movement is not considered. In populations with emigration and immigration, lethal control may induce compensatory immigration, if the source of attraction remains unchanged. Within the Columbia River Basin (Washington, U.S.A.), avian predators forage at dams because dams tend to reduce rates of emigration of juvenile salmonids (Oncorhynchus spp.), artificially concentrating these prey. We used differences in fatty acid profiles between Caspian Terns (Hydroprogne caspia) at coastal and inland breeding colonies and terns culled by a lethal control program at a mid-Columbia River dam to infer dispersal patterns. We modeled the rate of loss of fatty acid biomarkers, which are fatty acids that can be traced to a single prey species or groups of species, to infer whether and when terns foraging at dams had emigrated from the coast. Nonmetric multidimensional scaling showed that coastal terns had high levels of C20 and C22 monounsaturated fatty acids, whereas fatty acids of inland breeders were high in C18:3n3, C20:4n6, and C22:5n3. Models of the rate of loss of fatty acid showed that approximately 60% of the terns collected at Rock Island Dam were unlikely to have bred successfully at local (inland) sites, suggesting that terns foraging at dams come from an extensive area. Fatty acid biomarkers may provide accurate information about patterns of dispersal in animal populations and may be extremely valuable in cases where populations differ demonstrably in prey base. [ABSTRACT FROM AUTHOR]

Abstract: Nanopillar metal oxide thin films offer versatility as ultra high surface area supports and conductors. Metal oxide properties (e.g. stability, conductivity) can be tuned via phase and composition control to achieve desired application-specific functionality. Here we demonstrate phase control of high surface area thin films grown by glancing angle deposition and transformed to desired phases through high temperature annealing in a reducing environment. The post-annealed properties such as stoichiometry, phase, and morphology are shown to be largely dependent on initial film structure and hydrogen forming gas flow rate. Initially amorphous films of approximate stoichiometry Nb2O5 are transformed to NbO2 or NbN x O1−x through annealing. Transformation to oxygen-deficient phases is more easily achieved for films of higher initial porosity. Higher forming gas flow rates result in both increased oxygen removal and significantly less physical degradation of nanostructures. A phase map is included as a guide to phase formation and morphology control in annealed nanopillar niobium oxide films. [Copyright &y& Elsevier]

High-performance thin-layer chromatography is a separate ion technique commonly used to identify and quantify components in chemical mixtures. Sophisticated analytical tools are required to extract the full analytical power from this technique and especially for miniaturized planar chromatography its utility has not been harnessed. A new approach uses an elegant, simplified system assembled from ordinary consumer printers and scanners to perform separations on monolithic and nanostructured ultrathinlayer phases. This system is shown to outperform existing planar chromatographic tools for analysis on miniaturized plates. Analysis can be completed in a manner of minutes, running numerous samples in parallel at a reduced cost, with very low sample and reagent volumes, all using a familiar computer interface with common office peripherals. [ABSTRACT FROM AUTHOR]

Abstract: Glancing angle deposition was used to fabricate TiO2 thin film relative humidity sensors. These sensors have been shown to have an extremely high capacitive response along with sub-second response times. However, the thin film morphology that gives rise to the strong performance also renders the film vulnerable to ageing processes which can degrade sensor performance over a period of days. In this paper, the evolution of sensor response in time was studied. The response of our sensors to ultraviolet irradiation was investigated, and shown to not only reverse the ageing of our sensors, but also increase the overall device response. [Copyright &y& Elsevier]

Glancing angle deposition was used to produce ∼150-nm-thick silver nanoparticle films, which were evaluated as localized surface plasmon resonance (LSPR) biosensors. The films have a strong extinction peak around 368 nm in air due to LSPR. As the refractive index of the surrounding environment is increased, the extinction peak red-shifts with a linear dependence. The films were functionalized with 11-amino-1-undecanethiol and rabbit immunoglobulin G (rIgG) to allow for the detection of anti-rIgG binding. Binding of biomolecules to the nanoparticle surface increases the local refractive index and results in a red-shifting of the extinction peak. The wavelength shift at varying concentrations of anti-rIgG was measured and fit to the Langmuir isotherm. This yielded approximate values for the saturation response, Δλmax = 29.4 ± 0.7 nm, and the surface confined binding constant, Ka = (2.7 ± 0.3) × 106 M-1. The response to nonspecific binding was also investigated. [ABSTRACT FROM AUTHOR]

Abstract: A high-speed optical humidity sensor was fabricated from a nanostructured titanium dioxide thin film. A refractive index depth profile designed to yield a narrow-bandpass optical interference filter was obtained through nanoscale porosity variations produced by a physical vapor deposition technique known as glancing angle deposition (GLAD). The GLAD process provides film morphology control on the 10nm scale through a combination of deposition at highly oblique vapor incidence angles and controlled substrate motion. Under varying humidity conditions the transmittance spectrum of the filter shifts due to effective index changes of the porous structure resulting from water vapor adsorption/desorption. Performance analysis has shown that this device is highly sensitive, exhibits minimal hysteresis, and is extremely fast. The adsorption and desorption response times were measured to be 270ms and 160ms, respectively. [Copyright &y& Elsevier]

Presents a study which investigated a number of unique aspects involved in the simulation of long sputter system for the deposition of refractory metal barriers. Methodology used in the study; Simulation study of long throw sputtering; Results of the study; Conclusion.

Investigates on the temperature cycling effect on electromigration behavior under pulsed current conditions metallization used in very large scale integrated (VLSI) devices. Findings on the characteristic thermal response time for equilibrium establishment; Effect of joule heating due to an elevated current density employed in accelerated life testing; Use of transmission-line matrix (TLM) in solving partial differential equations.

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]